JP2003107787A - Image forming method and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming method, using an amorphous silicon photoreceptor, which prevents the occurrence of defective images due to a cleaning defect and is excellent in image reproducibility in long-term use as well. SOLUTION: The image forming method having a photoconductive layer composed of a non-single crystalline material consisting of silicon atoms as its parent body comprises using toners containing at least a binder resin, coloring agents and particulates containing at least a zinc oxide at 0.5 to 30 mol% in terms of a zinc element and metallic elements exclusive of the zinc element at 0.1 to 30 mol% of the zinc element in the zinc oxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for visualizing an electrostatic latent image in an image forming method such as an electrophotographic method, an electrostatic recording method, a magnetic recording method and a toner jet method.
And an image forming method using an amorphous silicon type photoconductor.

[0002]

2. Description of the Related Art Conventionally, as an image forming method, many methods such as an electrostatic recording method, a magnetic recording method and a toner jet method are known. For example, electrophotography generally involves forming an electrical latent image on an image bearing member such as a photoconductor using a photoconductive substance by various means, and then developing the latent image with toner. The image is obtained by forming a visible image, transferring the toner image to a recording medium such as paper, if necessary, and fixing the toner image on the recording medium by heat or pressure.

In general, various materials such as selenium, cadmium sulfide, zinc oxide, amorphous silicon (hereinafter referred to as a-Si), or organic materials are used as the material of the light receiving member used in the electrophotographic photoreceptor. Is proposed. Among these, a non-single crystalline deposition film containing silicon atoms represented by a-Si as a main component, for example, hydrogen and / or halogen (for example, fluorine, chlorine, etc.) is included (for example, hydrogen or dangling bond is compensated. ) A-Si
Amorphous deposited films such as those have been proposed as high-performance (high-resolution), high-durability, pollution-free photoconductors, and some of them have been put to practical use. Japanese Unexamined Patent Publication No. 54-86341 and U.S. Pat. No. 4,265,991 disclose a technique of an electrophotographic photoreceptor in which a photoconductive layer is mainly formed of a-Si. Further, JP-A-60-12554 discloses a surface layer containing carbon and halogen atoms on the surface of a photoconductive layer made of amorphous silicon containing silicon atoms, and further, JP-A-2-111962. In the publication, a-S
A photoreceptor having a surface protective lubricating layer provided on an i: H or aC: H photosensitive layer is disclosed.

Further, during image formation, after the transfer, the toner remaining on the image bearing member without being transferred to the recording medium is cleaned by various methods and stored as waste toner in a waste toner container. Image forming methods have been used in which the above steps are repeated.

For this cleaning step, conventionally blade cleaning, fur brush cleaning, roller cleaning, etc. have been used. In any of the methods, the transfer residual toner is mechanically scraped off or dammed to be collected in a waste toner container. From the viewpoint of the apparatus, the cleaning apparatus using the fur brush and the roller cleaning inevitably requires a large apparatus for providing the member, and therefore blade cleaning is preferably used from the viewpoint of downsizing the apparatus. However,
When a member such as a cleaning blade is pressed against the surface of the image carrier, the image carrier is abraded and shortened in life, or contaminants such as toner and paper dust are strongly adhered and fixed to the surface of the photoconductor. An image defect may occur. In particular, when using an amorphous silicon-based photoconductor as the photoconductor, the wear resistance of the photoconductor is high when a cleaning blade is used, and the contact surface of the cleaning blade with the photoconductor is easily scratched due to the hard surface. There is a problem in that the blade is likely to chatter due to the rubbing against the photoconductor, and a cleaning failure in which the transfer residual toner slips through the cleaning device is likely to occur, which adversely affects the charging and developing processes.

Therefore, in order to solve the above-mentioned problems related to cleaning, and also to save resources, reduce waste, and effectively use toner, a system without a waste toner without a cleaning device is provided. A system called simultaneous development cleaning or cleanerless has been desired.

However, the disclosure of the conventional technique related to simultaneous cleaning at the same time as development or cleanerless is disclosed in Japanese Patent Laid-Open Publication No. Hei 5 (1993) -53.
As described in Japanese Patent No. 2287, the focus is mainly on a positive memory, a negative memory and the like due to the influence of transfer residual toner on an image. However, with the increasing use of electrophotography, it is necessary to transfer a toner image to various recording media. In this sense, the technique disclosed in the above publication is applicable to various recording media. Was not satisfied.

[0008] Japanese Patent Application Laid-Open No. 59-133573, Japanese Patent Application Laid-Open No. 62-203182, and Japanese Patent Application Laid-Open No. 63-133179 are disclosed in the disclosure of the technology relating to cleanerless.
Japanese Patent Laid-Open No. 64-20587, Japanese Patent Laid-Open No. 2-3
Although there are JP-A No. 02772, JP-A No. 5-2289, JP-A No. 5-53482, and JP-A No. 5-61383, no detailed and specific configuration of the entire system is mentioned.

Various methods are known for the step of forming a visible image with toner. For example, as a method of visualizing an electric latent image, a cascade development method, a pressure development method, a magnetic brush development method using a two-component toner composed of a carrier and a toner, and the like are known. A non-contact one-component developing method in which the toner carrier flies from the toner carrier to the image carrier in a non-contact manner with the image carrier, using a magnetic toner and a rotary sleeve having a magnetic pole in the center, A magnetic one-component developing method in which toner is ejected between the sleeves by an electric field, and a contact one-component developing method in which a toner carrier is pressed against an image carrier to transfer the toner by an electric field are also used.

As a developing method which is preferably applied to a cleanerless system, in the conventional simultaneous development cleaning which essentially does not have a cleaning device, it has been indispensable to rub the surface of the image bearing member with the toner and the toner bearing member.
Many contact development methods have been studied in which toner or toner contacts an image bearing member. This is because, in order to collect the transfer residual toner in the developing device, the toner or the toner is considered to be in contact with the image carrier and rubbed, which is considered to be advantageous. However, in the simultaneous development cleaning or cleanerless process to which the contact development method is applied, there is an adverse effect that toner deterioration, toner carrier surface deterioration, image carrier surface deterioration or abrasion is likely to occur due to long-term use. Therefore, a simultaneous development cleaning method using a non-contact developing method has been desired.

Further, in the image forming method used in the electrophotographic apparatus, the electrostatic recording apparatus, etc., there are various methods for forming a latent image on an image carrier such as an electrophotographic photosensitive member or an electrostatic recording dielectric. It has been known.

For example, in the electrophotographic method, a photosensitive member using a photoconductive material as an image carrier is uniformly charged to a required polarity and potential, and then exposed to an image pattern to form an electrical latent image. The method of forming an image is common.

Conventionally, a corona charger (corona discharger) has often been used as a charging device for uniformly charging (including static elimination) the image carrier to a required polarity and potential. The corona charger is a non-contact type charging device, which is equipped with a discharge electrode such as a wire electrode and a shield electrode surrounding the discharge electrode, and the discharge opening is arranged in a non-contact manner so as to face the image carrier, which is the member to be charged. The surface of the image carrier is exposed to a discharge current (corona shower) generated by applying a high voltage to the discharge electrode and the shield electrode so that the surface of the image carrier is charged in a predetermined manner.

In recent years, as a charging device for a charged member such as an image carrier, a contact charging device has been proposed and put into practical use because it has advantages such as low ozone and low power as compared with a corona charger. There is.

The contact charging device is a conductive charging member (contact charging member / contact charger) of a roller type (charging roller), a fur brush type, a magnetic brush type, a blade type, etc. ) Is contacted and a predetermined charging bias is applied to the contact charging member to charge the surface of the body to be charged to a predetermined polarity and potential.

Contact charging mechanism (charging mechanism,
In the charging principle), two types of charging mechanisms, a discharge charging mechanism and a direct injection charging mechanism, coexist, and each characteristic appears depending on which one is dominant.

Discharge Charging Mechanism This is a mechanism in which the surface of the member to be charged is charged by the discharge phenomenon that occurs in the minute gap between the contact charging member and the member to be charged. Since the discharge charging mechanism has a constant discharge threshold between the contact charging member and the body to be charged, it is necessary to apply a voltage higher than the charging potential to the contact charging member. Further, although the amount of generation is much smaller than that of a corona charger, it is inevitable that a discharge product is generated, so that a harmful effect due to active ions such as ozone is unavoidable. In particular, when using an amorphous silicon type photoconductor, the hardness of the surface layer is much higher than that of an organic type photoconductor, which makes it very difficult to mechanically remove the discharge products attached to the photoconductor surface. Therefore, the discharge product adsorbs moisture, and the resistance of the surface of the photoconductor is lowered, so that the outline of the image is not clear due to the flow of the latent image potential, and a blurred image or a flow image tends to occur. As a measure to prevent such image defects,
A measure to prevent a defective image by heating an amorphous silicon-based photoconductor and removing moisture adsorbed on a discharge product has been taken and implemented.

Direct Injection Charging Mechanism This is a system in which the surface of the member to be charged is charged by directly injecting charges from the contact charging member into the member to be charged. It is also called direct charging, injection charging, or charge injection charging. More specifically, a medium-resistance contact charging member comes into contact with the surface of the member to be charged and directly injects the charge into the surface of the member to be charged without a discharge phenomenon, that is, basically without using discharge. Therefore, even if the applied voltage to the contact charging member is equal to or lower than the discharge threshold value, the charged body can be charged to a potential corresponding to the applied voltage. Since this charging system does not generate ions, no harm is caused by the discharge products. However, since it is the direct injection charging, the contact property of the contact charging member to the member to be charged greatly affects the charging property. Therefore, in order to contact the body to be charged more frequently, the contact charging member preferably has a denser contact point, has a large speed difference from the body to be charged, or the like.

In the contact charging device, a roller charging method using a conductive roller (charging roller) as a contact charging member is preferable from the viewpoint of charging stability and is widely used. The discharge charging mechanism is dominant in the charging mechanism in the conventional roller charging.

The charging roller is made of a conductive or medium-resistance rubber material or foam. Further, there is also one in which these are laminated to obtain desired characteristics.

The charging roller has elasticity in order to obtain a constant contact state with the body to be charged. Therefore, the friction roller has a large friction resistance, and in many cases, is driven by the body to be charged or driven with a slight speed difference. It

However, even in such a contact charging device, since the essential charging mechanism uses the discharge phenomenon from the contact charging member to the photosensitive member, it is applied to the contact charging member as described above. The voltage is required to have a value equal to or higher than the surface potential of the photosensitive member, a certain amount of ozone is generated, and the above-described image defect is likely to occur.

Further, when AC charging is performed for uniform charging, ozone is further generated, vibration noise (AC charging sound) of the contact charging member and the photoconductor due to the electric field of AC voltage is generated, and discharge is caused. Deterioration of the surface of the photoconductor has become remarkable, which has been a new problem.

Therefore, charging by direct injection charging which does not depend on discharge is preferable, but in the case of the conventional roller type charging member, even if injection charging is attempted, the absolute charging ability is deteriorated, contact is insufficient, and contact is caused by the roller shape. Irregularity or uneven charging due to adhered substances on the body to be charged easily occurs.

Further, in the injection charging by the fur brush, although the contact point with the photoconductor is increased and the injection charging property is improved as compared with the conventional roller type charging member, the absolute charging ability is low and uneven charging occurs. It is easy to cause image defects due to uneven charging.

On the other hand, in the magnetic brush charging, a member (magnetic brush charger) having a magnetic brush portion formed in the shape of a brush by magnetically restraining conductive magnetic particles with a magnet roll or the like is used as a contact charging member. The conductive magnetic particles forming the brush portion have a particle size of 5 to 50 μm, and are provided with a sufficient speed difference from the photoconductor, and are brought into contact with the photoconductor for charging. With such a charging mechanism, the contact point with the photoconductor is much higher than that of a charging member using a fur brush, and even charging by injection enables uniform charging, which causes image defects. Absent.
However, the device configuration is complicated, the device tends to be large, and the conductive magnetic particles forming the magnetic brush portion may be dropped and adhered to the photoconductor.

Here, consider the case where these contact charging methods are applied to the simultaneous developing cleaning method and the cleanerless image forming method. In the simultaneous development cleaning method and the cleanerless image forming method, the transfer residual toner remaining on the photoconductor because it does not have a cleaning member directly contacts the contact charging member and is attached or mixed. Further, in the case of the charging method in which the discharge charging mechanism is dominant, the adhesion of the toner to the charging member is deteriorated due to the toner deterioration due to the discharge energy. When the commonly used insulating toner adheres to or mixes with the contact charging member, the charging property is deteriorated.

In the case of the charging method in which the discharge charging mechanism is predominant, the decrease in the chargeability of the member to be charged rapidly occurs when the toner layer adhering to the surface of the contact charging member becomes a resistance that obstructs the discharge voltage. Happen to.

On the other hand, in the case of the charging method in which the direct injection charging mechanism is dominant, the transfer residual toner adhered or mixed reduces the contact probability between the surface of the contact charging member and the member to be charged. The chargeability of the body is reduced. This decrease in the uniform charging property of the member to be charged results in a decrease in the contrast and uniformity of the electrostatic latent image after image exposure, increasing the unevenness of image density or increasing fog.

Further, in the simultaneous cleaning method for development and the cleanerless image forming method, the point is to stably collect the transfer residual toner in the developing process so that the recovered toner does not deteriorate the developing characteristics. The charge polarity and the charge amount are controlled during the charging process.

This will be specifically described by taking a general laser printer as an example. In the case of reversal development using a charging member that applies a negative polarity voltage, a negatively charging photosensitive member and a negatively charging toner, in the transfer process, transfer the image visualized by the positive polarity transfer member to the recording medium. However, due to the relationship between the type of recording medium (difference in thickness, resistance value, dielectric constant, etc.) and the image area, the charging polarity of the transfer residual toner changes from plus to minus. However, due to the negative polarity charging member when charging the negatively chargeable photoconductor, even the transfer residual toner along with the surface of the photoconductor is uniformly moved to the negative side even if it is swung to the positive polarity in the transfer process. If the charging polarities can be made uniform, when reversal development is used as the developing method, negatively charged transfer residual toner remains in the bright portion potential portion of the toner to be developed, and the toner is developed. Due to the developing electric field, the dark portion potential that should not be drawn is attracted toward the toner carrier, and the transfer residual toner is collected without remaining on the photoconductor having the dark portion potential. That is, by controlling the charging polarity of the transfer residual toner at the same time as the charging of the photosensitive member by the charging member, the simultaneous cleaning for development and the cleanerless image forming method are established.

However, in the contact charging step, when the transfer residual toner in an amount exceeding the toner charge polarity controllability of the contact charging member adheres to or mixes with the contact charging member, the charge polarity of the transfer residual toner can be made uniform. This makes it difficult to collect the toner by the developing member. Even if the transfer residual toner is collected on the toner carrier by a mechanical force such as rubbing, if the transfer residual toner is not uniformly charged, the chargeability of the toner on the toner carrier is adversely affected. Affect the developing characteristics.

That is, in the simultaneous development cleaning and cleanerless image forming method, the charge control characteristic of the transfer residual toner when passing through the charging member and the adhesion / mixing characteristic to the charging member are the durability characteristic and the image quality characteristic of the image device. It is closely connected.

Japanese Patent Publication No. 7-99442 discloses a structure in which powder is applied to the contact surface of the contact charging member with the surface to be charged in order to improve the charging property of the photosensitive member and to perform stable and uniform charging. ing. However, the contact charging member (charging roller) is driven by the member to be charged (photoreceptor) to rotate (no speed difference drive), and the generation of ozone products is much less than that of a corona charger such as a scorotron. However, the charging principle is still mainly the discharge charging mechanism as in the case of the roller charging described above. In particular, in order to obtain more stable charging uniformity, a voltage in which an AC voltage is superimposed on a DC voltage is applied, so that the ozone products are more likely to be generated by the discharge. Therefore, when the device is used for a long period of time, adverse effects such as image deletion due to ozone products are likely to appear. Further, when applied to a cleanerless image forming apparatus, it becomes difficult for the applied powder to uniformly adhere to the charging member due to the mixture of the transfer residual toner, and the effect of uniform charging is diminished.

Further, in Japanese Patent Application Laid-Open No. 5-150539, in an image forming method using contact charging, toner particles and silica fine particles which cannot be completely cleaned by blade cleaning are formed on the surface of the charging means during repeated image formation. In order to prevent charging inhibition due to adhesion and accumulation on
It is disclosed that the toner contains at least developer particles and conductive particles having an average particle size smaller than that of the developer particles. However, since the contact charging or the proximity charging used here is based on the discharge charging mechanism instead of the direct injection charging mechanism, there is the above-mentioned problem due to the discharge charging. Furthermore,
When the above-mentioned proposal is applied to a cleanerless image forming apparatus, the large amount of conductive fine particles and transfer residual toner have an influence on the charging property due to passing through the charging process, as compared with the case where a cleaning mechanism is provided. No consideration is given to the recoverability of the conductive fine particles and the transfer residual toner in the developing step, and the influence of the recovered conductive fine particles and the transfer residual toner on the developing characteristics of the toner. Further, when the direct injection charging mechanism is applied to the contact charging, the conductive fine particles are not supplied to the contact charging member in the required amount, and the charging failure occurs due to the influence of the transfer residual toner.

Further, in the simultaneous development image forming method, it is specified in Japanese Patent Laid-Open No. 11-15206 that the simultaneous development cleaning performance is improved by improving the charge control characteristic when the transfer residual toner passes through the charging member. An image forming method using a toner having toner particles containing carbon black and a specific azo iron compound and inorganic fine powder has been proposed. Further, in the simultaneous development image forming method, it has also been proposed to improve the simultaneous development cleaning performance by reducing the amount of transfer residual toner with a toner having a transfer efficiency that defines the shape factor of the toner. However, since the contact charging used here is not the direct injection charging mechanism but the discharge charging mechanism, there is the above-mentioned problem due to the discharge charging. Further, although these proposals have the effect of suppressing the decrease in the charging uniformity of the photoconductor due to the transfer residual toner of the contact charging member, the effect of positively increasing the charging property cannot be expected.

Further, in a commercially available electrophotographic printer, a roller member that comes into contact with the photosensitive member is used during the transfer process and the charging process to assist or control the recovery property of the residual toner after the development. There is also an image forming apparatus.
Such an image forming apparatus exhibits a good simultaneous development cleaning property and can greatly reduce the amount of waste toner, but the cost is high and the advantage of simultaneous development cleaning is lost in terms of downsizing.

On the other hand, JP-A-10-307456
Japanese Patent Laid-Open Publication No. JP-A-2004-264242, an image forming apparatus applying a toner containing toner particles and conductive charging promoting particles having a particle diameter of ½ or less of a toner particle diameter to a simultaneous developing image forming method using a direct injection charging mechanism Is disclosed. According to this proposal, an image forming apparatus for simultaneous development and cleaning which can reduce the amount of waste toner significantly without generating discharge products and is advantageous in downsizing can be obtained. Alternatively, a good image that does not cause diffusion can be obtained.

Further, in Japanese Unexamined Patent Publication No. 10-307421, toner containing conductive particles having a particle diameter of 1/50 to 1/2 of the toner particle diameter is directly injected to form a cleaning image by using a charging mechanism. There is disclosed an image forming apparatus which is applied to the method and has conductive particles having a transfer promoting effect.

Further, in Japanese Patent Application Laid-Open No. 10-307455, the particle size of the fine particles is set to be equal to or smaller than the size of one pixel of the constituent pixels, and the particle size of the fine particles is set to 10 nm to 50 μm in order to obtain better charging uniformity. It is described to do.
In Japanese Patent Laid-Open No. 10-307457, the conductive particles are set to about 5 μm or less, preferably 20 nm to 5 μm in order to make it difficult to visually recognize the influence of a poorly charged portion on an image in consideration of human visual characteristics. It is described to do.

Further, according to Japanese Patent Laid-Open No. 10-307458, by setting the particle size of the fine particles to be equal to or smaller than the toner particle size,
It is possible to prevent development of toner during development, or to prevent development bias from leaking through fine particles to eliminate image defects. Further, the fine particles have a particle size of 0.1 μm.
There is described a simultaneous developing and cleaning image forming method using a direct injection charging mechanism, which solves the problem of blocking the exposure light by embedding fine particles in the image carrier by setting a larger value, and realizes excellent image recording. .

According to Japanese Patent Application Laid-Open No. 10-307456, fine particles are externally added to the toner, and the fine particles are interposed at least at the contact portion between the flexible contact charging member and the image carrier, and the fine particles are developed. Disclosed is a simultaneous development developing image forming apparatus capable of obtaining a good image that does not cause charging failure and light blocking of image exposure by being attached to the image carrier in the process and remaining on the image carrier even after the transfer process and carried. Has been done.
Certainly, according to these proposals, the simultaneous cleaning image forming method for development can be achieved, and the cleanerless system becomes possible.

However, when an amorphous silicon type photoconductor is used as the photoconductor, since the capacity of the amorphous silicon photoconductor is large, when the charging potential of the same potential is placed on the photoconductor, a larger amount of charge than the organic photoconductor is charged. Electric current is needed. Therefore, it is necessary to further increase the number of contact points between the photoconductor and the charging member, which are in contact with each other via the conductive particles, and the conductive particles must be stably supplied to the contact portion.

On the other hand, in the above proposal, a fine powder having low resistance, that is, high conductivity is used as the electrification-promoting particles, but the resistance characteristic of the surface of a general photoconductor is not uniform to some extent, and low resistance is obtained. There are inevitably small points, so-called pinholes.

When a contact charging mechanism is used by combining a photoconductor having such pinholes with conductive fine particles, an excessive current flows in the pinholes, resulting in image defects. For example, a slight defect appears as a black dot,
In the severe case, the current required for charging is concentrated in the pinhole and the photoconductor is not charged. Even if it is a non-image part, it develops corresponding to the contact part of the charging member, which causes a problem of leak image. Occur. Such a problem occurs particularly remarkably under high humidity where the resistance of the member tends to decrease.

In the prior art, such practical problems have not been taken into consideration.

[0047]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and when an amorphous silicon type photosensitive member is used, the toner remaining on the transfer is properly removed by a cleaning device so that the cleaning step is performed. Prevents deterioration of primary charging due to transfer residual toner that has slipped through,
An object is to prevent the generation of a defective image due to poor cleaning. Further, it is possible to provide an image forming method which suppresses an excess current in a pinhole existing on a photoconductor, has stable charging performance even under high humidity, and has excellent image reproducibility even when used for a long time. It is an issue.

Further, according to the present invention, a cleaner having excellent image reproducibility can be provided with stable primary charging property even when simultaneous development cleaning is applied to an image forming method using an amorphous silicon type photoreceptor. An object of the present invention is to provide an image forming method capable of forming a less image.

Further, it is an object of the present invention to provide a cleanerless image forming method capable of stably obtaining a good image even under high humidity for a long period of time.

[0050]

Means for Solving the Problems As a result of intensive investigations by the present inventors, in an image forming method using an amorphous silicon photoconductor, by using a toner containing specific fine particles, good fluidity of the toner is obtained. It has been found that it is possible to prevent the cleaning failure and to extend the life of the photoconductor. The present inventors have also found that the above toner can be suitably applied to an image forming method of a cleanerless system.

That is, the present invention is as follows.

(1) A charging step of charging a photoreceptor as an image carrier, an electrostatic latent image forming step of forming an electrostatic latent image on the charged photoreceptor, and a toner carrier Image forming including at least a developing step of transferring the toner to the electrostatic latent image to form a toner image and a transfer step of electrostatically transferring the toner image formed on the photoconductor in the developing step onto a transfer material. In the method, the photoreceptor has a conductive support and a photoconductive layer made of an amorphous material having a silicon atom as a matrix, and the toner comprises a binder resin, a colorant, and at least zinc oxide. 0.5 to 0.5 in terms of zinc element
An image forming method, comprising at least 30 mol% of fine particles containing 0.1 to 30 mol% of a metal element other than zinc element with respect to the zinc element in the zinc oxide.

(2) The image forming method according to (1), wherein the metal element other than the zinc element is at least one element selected from aluminum, gallium, indium, tin, and germanium.

(3) The image forming method according to (1) or (2), wherein elements other than zinc are contained in zinc oxide.

(4) The image forming method according to any one of (1) to (3), wherein the fine particles are composed of base particles and zinc oxide supported on the surfaces of the base particles.

(5) The image forming method according to (4), wherein the base particles are inorganic particles.

(6) The image forming method according to (4) or (5), wherein the base particles are titanium oxide or tin oxide.

(7) The resistance of the fine particles is 1 × 10 ² to 1
× 10 ⁹ Ωcm (1) to (6)
The image forming method of any one of.

(8) The image formation according to any one of (1) to (7), wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner and is 0.05 μm or more. Method.

(9) The image formation according to any one of (1) to (8), wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner and is 0.1 μm or more. Method.

(10) The release rate of the fine particles in the toner is 5 to 90%, (1) to
The image forming method according to any one of (9).

(11) The image forming method according to any one of (1) to (10), wherein the fine particles are present on the surface of the toner particles in a ratio of 0.3 or more per one toner particle.

(12) The fine particles are contained in an amount of 0.2 to 10% by mass based on the whole toner (1)
To (11) the image forming method.

(13) The image forming method according to any one of (1) to (12), wherein the toner further contains magnetic iron oxide.

(14) The toner has an average circularity of 0.
970 or more, and the strength of magnetization in a magnetic field of 79.6 kA / m (1000 Oersted) is 10 to 50 Am ² /
It is characterized in that it is kg (emu / g) (1)-
The image forming method according to any one of (13).

(15) The mass average particle diameter of the toner is 3 to
It is 10 micrometers, The image forming method in any one of (1)-(14) characterized by the above-mentioned.

(16) The image forming method according to any one of (1) to (15), wherein the photoreceptor further has a surface layer made of an amorphous hydrogenated carbon film.

(17) The amorphous hydrogenated carbon film has a hydrogen content of 41 to 60% in terms of element ratio (1
6) The image forming method.

(18) The image forming method according to any one of (1) to (17), wherein the charging step is a step of charging the photosensitive member by bringing the charging member into contact with the photosensitive member.

(19) The image forming method according to (18), wherein in the charging step, the charging member and the photoconductor are in contact with each other through the fine particles.

(20) The transfer residual toner remaining on the photoconductor after the transfer step is collected by the toner carrier in the developing step (1) to (1)
The image forming method according to any one of 9).

(21) The charging step is a step of charging the photosensitive member in a state where 10 ³ particles / mm ² or more of fine particles are present in the contact portion between the charging member and the photosensitive member. The image forming method according to any one of (18) to (20).

(22) The developing step is a step of developing by a non-contact developing method in which the photosensitive member and the toner carrying member are in non-contact with each other.
The image forming method according to any one of 1).

(23) The charging step is a step of charging the photoconductor by applying a voltage to a roller member having an Asker C hardness of 25 to 50. (1) to (22) Either image forming method.

(24) The charging step is a step of charging the photosensitive member by applying a voltage to the roller member, and at least the surface of the roller member is a dent having an average cell diameter of 5 to 300 μm in terms of sphere. Has
The porosity of the roller member surface is 15 to 90% when the depressions are used as voids (1) to (2).
The image forming method according to any one of 3).

(25) The image in any one of (1) to (22), wherein the charging step is a step of charging the photoconductor by applying a voltage to a brush member having conductivity. Forming method.

(26) Charging means for charging the photoreceptor as an image carrier, electrostatic latent image forming means for forming an electrostatic latent image on the charged photoreceptor, and a toner carrier. An image forming apparatus including at least developing means for transferring toner to the electrostatic latent image to form a toner image, and transfer means for electrostatically transferring the toner image formed on the photoconductor in the developing step onto a transfer material. The photoreceptor has a conductive support and a photoconductive layer made of an amorphous material having silicon atoms as a matrix, and the toner contains a binder resin, a colorant, and at least zinc oxide. 0.5 ~ in terms of zinc element
An image forming apparatus containing at least 30 mol% of fine particles containing 0.1 to 30 mol% of a metal element other than zinc element with respect to the zinc element in the zinc oxide.

(27) The metal element other than the zinc element is
(26) The image forming apparatus according to (26), which is one or more elements selected from aluminum, gallium, indium, tin, and germanium.

(28) An element other than zinc is contained in zinc oxide (26) or (2)
7) The image forming apparatus.

(29) The image forming apparatus according to any one of (26) to (28), wherein the fine particles are composed of base particles and zinc oxide carried on the surfaces of the base particles.

(30) The image forming apparatus according to (29), wherein the base particles are inorganic particles.

(31) The matrix particles are titanium oxide or tin oxide (29) or (3)
0) The image forming apparatus.

(32) The resistance of the fine particles is 1 × 10 ² to
1 × 10 ⁹ Ωcm (26)-
The image forming apparatus according to any one of (31).

(33) The volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner, and is 0.05 μm.
The image forming apparatus according to any one of (26) to (32), which is as described above.

(34) The image formation according to any one of (26) to (33), wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner and is 0.1 μm or more. apparatus.

(35) The release rate of the fine particles in the toner is 5 to 90% (26)
The image forming apparatus according to any one of (34) to (34).

(36) The image forming apparatus according to any one of (26) to (35), wherein the fine particles are present on the surface of the toner particles in a ratio of 0.3 or more per one toner particle.

(37) The fine particles are contained in an amount of 0.2 to 10% by mass based on the whole toner (2)
The image forming apparatus according to any one of 6) to (36).

(38) The image forming apparatus according to any one of (26) to (37), wherein the toner further contains magnetic iron oxide.

(39) The toner has an average circularity of 0.
970 or more, and the strength of magnetization in a magnetic field of 79.6 kA / m (1000 Oersted) is 10 to 50 Am ² /
It is characterized by being kg (emu / g) (26)-
The image forming apparatus according to any one of (38).

(40) The toner has a mass average particle diameter of 3 to
The image forming apparatus according to any one of (26) to (39), which has a thickness of 10 μm.

(41) The photoconductor further has a surface layer made of an amorphous hydrogenated carbon film (2)
The image forming apparatus according to any one of 6) to 40.

(42) The hydrogen content of the amorphous hydrogenated carbon film is 41 to 60% in terms of element ratio (4)
The image forming apparatus of 1).

(43) The charging means is characterized in that the charging member is brought into contact with the photosensitive member to carry out charging.
The image forming apparatus according to any one of (42).

(44) The image forming apparatus according to (43), wherein in the charging means, the charging member and the photoconductor contact each other through the fine particles.

(45) The image forming apparatus according to any one of (26) to (44), wherein the transfer residual toner remaining on the photoconductor after the transfer is collected by the toner carrier of the developing means. .

(46) The charging means charges the photoconductor in a state where 10 ³ particles / mm ² or more of fine particles are present in the contact portion between the charging member and the photoconductor ( The image forming apparatus according to any one of 43) to (45).

(47) The image of any one of (26) to (46), wherein the developing means develops by a non-contact developing method in which the photosensitive member and the toner carrying member are in non-contact with each other. Forming equipment.

(48) The charging means charges the photosensitive member by applying a voltage to a roller member having an Asker C hardness of 25 to 50 (26) to
The image forming apparatus according to any one of (47).

(49) The charging means charges the photoreceptor by applying a voltage to the roller member, and at least the surface of the roller member has a depression having an average cell diameter of 5 to 300 μm in terms of sphere. And the porosity of the roller member surface is 15 to 90 when the depressions are used as voids.
%, The image forming apparatus according to any one of (26) to (48).

(50) The image forming apparatus according to any one of (26) to (49), wherein the charging means charges the photosensitive member by applying a voltage to a brush member having conductivity.

[0102]

BEST MODE FOR CARRYING OUT THE INVENTION The image forming method of the present invention will be described.

In the image forming method of the present invention, an amorphous silicon type photosensitive member is used as the member to be charged. Therefore, high durability and high quality images can be obtained. Further, in the charging step, by using the step of charging the photosensitive member by applying a voltage to the charging member which forms the contact portion with the photosensitive member and is brought into contact with the photosensitive member, many advantages such as low ozone and low power can be obtained. To be

Further, in the present invention, a toner having fine particles containing at least zinc oxide and a metal element other than the zinc element is used. The fine particles have good dispersibility, and therefore the fluidity of the toner can be improved. Further, since it is possible to easily loosen the toners by mixing the fine particles in the toner, even when a cleaning device using a cleaning blade is applied to the image forming method of the present invention, aggregation of the toner reaching the cleaning portion is small, The load on the blade due to the aggregate is suppressed,
Since deterioration such as scratches is suppressed, cleaning failure is prevented. Further, since loosened toner and fine particles having good dispersibility are present in the contact portion between the cleaning blade and the photoconductor, the rubbing force between the cleaning blade and the photoconductor is reduced, so that abrasion of the photoconductor is reduced. And leads to higher durability. In particular, when a toner having a high degree of circularity is used for the purpose of improving transferability, a cleaning device using a blade is liable to cause cleaning failure, and when such a toner is used, the cleaning effect is particularly exerted. .

Further, as described above, the inclusion of the fine particles reduces the cohesiveness of the toner and improves the fluidity, so that the triboelectrification imparting ability to the toner is improved, the charging rises quickly, and uniform charging is performed. Granting is easy to achieve. Therefore, it is possible to reduce fog (particularly, fog caused by the reversal component) that tends to occur in the case of non-uniform charging, and prevent image density reduction that tends to occur when the charging speed rises slowly, thereby obtaining an excellent image.

Further, the fine particles contained in the toner used in the present invention contain at least zinc oxide in an amount of 0.5 to 30 mol% in terms of zinc element based on the whole fine particles, and a metal element other than zinc element in zinc oxide. 0.1 to 30 mol% with respect to the elemental zinc. By using the toner containing such fine particles, the fine particles present in the contact portion between the contact charging member and the photoconductor adhere to the photoconductor during the developing process and remain on the photoconductor after the transferring process. By being carried, charging becomes uniform and a good image can be obtained. This effect can be seen regardless of the presence or absence of the cleaning process.

If the content of the elemental zinc is less than 0.5 mol% with respect to the total amount of the fine particles, the resistance of the fine particles becomes high, and the charging failure easily occurs due to the contamination of the primary charging. Further, since the amount of zinc oxide existing on the surface of the fine particles is reduced, the load on the cleaning blade is increased. If the content of the element other than zinc in the fine particles is less than 0.1 mol% with respect to the zinc element, the resistance tends to be high and contamination of the primary charging is likely to occur.

On the other hand, the content of zinc element in the fine particles is 30.
If it is more than mol%, the resistance becomes too low, the potential leaks to the pinhole portion of the photoconductor, the charged charge of the toner easily escapes, the charging rises slowly, and image defects such as fogging easily occur. If the content of the element other than the zinc element in the fine particles is more than 30 mol% with respect to the zinc element, the doping effect of this element on zinc oxide is weakened, the characteristics of the elements other than zinc are likely to appear, and the resistance increases. This is not preferred because it easily causes contamination of the primary charge.

The above fine particles are 0.5 to 3 in terms of zinc element.
The conductivity is expressed by the zinc oxide content of 0 mol%. Therefore, the current is 30m when voltage is applied.
It was found that the current flows through zinc oxide controlled to be ol% or less, which is probably why it is difficult for a large current to flow. As a result, it has been found that even if there are pinholes on the surface of the photoconductor, excessive current is suppressed and at the same time image defects are suppressed. On the other hand, since the fine particles contain 0.5 mol% or more of a zinc compound, they have a relatively low resistance as fine particles, and if used in the charging step within the range of the normal current value, the charging uniformity becomes very high. It has also become clear that it can be improved.

In the above fine particles, a metal element other than zinc (hereinafter sometimes referred to as “different element”) is preferably contained in zinc oxide. Further, zinc oxide is preferably present on the surface of the fine particles. That is, it is preferable that the fine particles are composed of zinc oxide containing a different element (hereinafter sometimes referred to as “zinc oxide compound”) and host particles carrying the zinc oxide compound.

By including fine particles of such a mode in the toner, the following effects can be expected, especially in the case of a cleanerless image forming method. That is, the fine particles present in the contact portion between the contact charging member and the photoconductor adhere to the photoconductor during the developing process and remain on the photoconductor after the transferring process and are carried. When the fine particles of the above aspect are used, the zinc oxide compound and the base particles are loosened in the charging step, and a finer zinc oxide compound than the fine particles having the charging member and the zinc oxide compound on the surface is present between the photoconductor and the charging member. Even if an amorphous silicon type photoconductor is used, the number of contact points between the photoconductor and the charging member is increased by the interposition so that charging is uniform and a good image can be obtained.

The fine particles having a zinc oxide compound on the surface are
The conductivity is exhibited by zinc oxide containing a different element, which is carried on the surface of the base particles. Therefore, it was found that when the voltage was applied in the charging step, the current would flow only through the surface of the fine particles, but probably because of this, a large current would hardly flow. As a result, it has been found that even if there are pinholes on the surface of the photoconductor, excessive current is suppressed and at the same time image defects are suppressed. On the other hand, it has been clarified that since the fine particles have low resistance, the uniformity of charging can be greatly improved if they are used in the charging step within the range of the usual current value.

When such fine particles carrying zinc oxide on the surface are not used, a defective image due to poor cleaning or, in the case of a cleanerless system, primary charging property is obstructed and a defective image due to defective primary charging occurs. is there.

When the elements other than zinc oxide (heterogeneous elements) contained in zinc oxide are one or more elements selected from Al, Ga, In, Sn, and Ge, the effect of suppressing the excess current is further improved. To be demonstrated. It is considered that the number of electrons in the conduction band is appropriately adjusted by appropriately selecting the valence and atomic radius of the different element, but the exact reason is not clear.

Inorganic particles are preferred as the base particles carrying zinc oxide. This is due to the strength against stress at the contact portion between the charging member and the photoconductor.

The material of the inorganic particles that is particularly preferably used for the base particles is titanium oxide whose particle size and resistance value are easy to control,
It is tin oxide. Specifically, for example, fine particles of titanium oxide surface-treated with tin oxide / antimony, fine particles of stannic oxide doped with antimony, or fine particles of stannic oxide are used.

Commercially available tin oxide / antimony treated conductive titanium oxide fine particles include, for example, EC-300.
(Titanium Industry Co., Ltd.), ET-300, HJ-1, H
I-2 (above, Ishihara Sangyo Co., Ltd.), WP (Mitsubishi Materials Co., Ltd.), etc. are mentioned.

Examples of commercially available antimony-doped conductive tin oxides include T-1 (Mitsubishi Materials Corporation) and SN-100P (Ishihara Sangyo Co., Ltd.), and commercially available stannic oxides include SH- S (Japan Chemical Industry Co., Ltd.) and the like can be mentioned.

In the present invention, as a method of incorporating fine particles into a toner, there are an internal addition in which the fine particles are contained in the toner particles constituting the toner and an external addition in which the fine particles are added after the toner particles are formed. In order to carry out the above-described effects of the present invention more quickly and efficiently, it is preferable that the zinc oxide fine particles are present on the toner surface, and as such means for achieving, external control that is easy to control is preferable. In addition, means for exposing the surface by a mechanical method such as crushing or polishing after the internal addition is included. In addition,
A method for producing a toner containing fine particles used in the present invention will be described later.

Zinc oxide and different elements in the present invention
The resistance value of the fine particles containing is 10 ²-10⁹In Ω · cm
Preferably there is. The resistance value of the particles is 10⁹Ω · cm
If it is larger than the
When applied to the image forming method used, the fine particles are used as a charging member.
Do not interpose in the contact area with the photoconductor or in the charging area near it.
The fine particles of the contact charging member to the photoreceptor
Even if the contact property is maintained, the charge injection property to the photoconductor is reduced.
However, the charging promotion effect for obtaining good charging property cannot be obtained.
It is not preferable because it does not exist. In addition, the effect of accelerating the charging of fine particles
In order to pull it out sufficiently and to obtain good chargeability stably
Means that the resistance value of the fine particles is
It is preferably smaller than the resistance of the contact portion with the optical body.

As a method for controlling the resistance of the fine particles within the above range, a different element whose valence is selected according to the acid value of zinc of zinc oxide (the valence of zinc of zinc oxide is divalent) is contained, and the content thereof is adjusted. Control is possible by adjusting.

That is, the divalent metal oxide as a different element contained in the fine particles is preferably a trivalent or higher valent element, and examples thereof include Al, Ga, In, Sn and Ge.

The effect of reducing the resistance was found by incorporating the above elements into zinc oxide. Further, it was confirmed that the effect of suppressing the resistance fluctuation due to the environment was also exerted, and it was confirmed that the effect was particularly effective in increasing the resistance in a low humidity environment.

If the resistance value of the fine particles is less than 10 ² Ωcm, when there is a pinhole in the photoconductor, the electric charge is concentrated on the part, the member is broken, and the image is cut off in the lateral direction. However, a leak image is likely to occur, which is not preferable.

FIG. 1 shows a method for measuring the volume resistance value of fine particles containing zinc oxide. The cell B of FIG. 1 was filled with 0.5 g of fine particles left in a measurement environment for 24 hours or more, and the electrodes 21 and 22 were arranged so as to contact the powder (fine particle sample),
A voltage is applied between the electrodes, and the current flowing at that time is measured by an ammeter 2.
It is obtained by measuring at 4. The measurement conditions are 23
In the environment of ℃, relative humidity 65%, the contact area between the powder and the electrode is 2.26 cm ² , pressure is applied to the upper electrode with a load of 15 kg, the cell height (d) is measured with a caliper, and the applied voltage is 50
The current was measured at V, and the volume resistance was calculated from the area and height.

The particle diameter of the fine particles is preferably smaller than the volume average particle diameter of the toner particles in the toner, and the volume average particle diameter of the fine particles is 0.0.
It is more preferably 5 μm or more.

If the volume average particle diameter of the fine particles is less than 0.05 μm, the toner particles are less likely to be loosened when a cleaning method using a cleaning blade is used,
Further, the fine particles themselves easily slip through the cleaning blade, and a defective image is likely to occur due to poor cleaning, which is not preferable. Further, in the cleanerless image forming method, the smaller the particle size of the fine particles present in the portion where the photoconductor and the charging member contact each other, the larger the number of contact points and the higher the charging uniformity. However, if the volume average particle size of the fine particles is too smaller than 0.05 μm, since the fine particles behave in synchronization with the toner particles, most of the fine particles migrate to the transfer material together with the toner particles during the transfer process. As a result, the supply of the fine particles to the charging process section becomes insufficient, and the charging uniformity is likely to deteriorate, which is not preferable.

If the volume average particle size of the fine particles is small, the content of the fine particles in the whole toner must be set small in order to prevent the deterioration of the developing property under high humidity. If the average particle size of the fine particles is less than 0.05 μm, an effective amount of the fine particles cannot be secured, and in the case of an image forming method using a cleanerless, in the charging step, insulating transfer residual toner adheres to or mixes with the contact charging member. Insufficient amount of fine particles to overcome charging inhibition and to charge the photoconductor satisfactorily cannot be present in the contact area between the charging member and the photoconductor or in the charging area in the vicinity thereof, resulting in poor charging. It will be easier. More preferably, it is 0.1 μm or more.

When the volume average particle diameter of the fine particles is larger than the volume average particle diameter of the toner particles, the fine particles are easily separated from the toner particles when the fine particles are mixed with the toner, and the particles are transferred from the developing container to the photoreceptor in the developing step. The supply amount of fine particles is insufficient and it is difficult to obtain sufficient chargeability. Further, the fine particles that have fallen off the charging member block or diffuse the exposure light for writing the electrostatic latent image, thus causing a defect in the electrostatic latent image and degrading the image quality. Further, if the average particle size of the fine particles is too large, the fine particles easily fall off from the charging member, and the number of particles per unit mass decreases. For this reason, in consideration of reduction and deterioration due to falling of the fine particles from the charging member, the fine particles are sequentially supplied to the contact area between the charging member and the photosensitive member or the charging area in the vicinity thereof so as to be interposed. Further, in order for the contact charging member to maintain close contact with the image carrier through the fine particles and stably obtain good chargeability, the content of the fine particles in the whole toner must be increased.

However, if the content of the fine particles is too large, the triboelectrification ability and the developability are lowered especially in a high humidity environment, and the image density is lowered and the toner is scattered. From such a viewpoint, the volume average particle diameter of the fine particles is preferably 5 μm or less. Considering the abrasion resistance of the photoconductor, the number% of particles having a volume average particle diameter of 5 μm or more in the fine particles is more preferably 3% or less.

The volume average particle diameter of the toner and fine particles containing zinc oxide in the present invention can be measured by various methods such as Coulter counter TA-II type or Coulter Multisizer (manufactured by Coulter Co.). Is Coulter Multisizer (made by Coulter)
It is preferable that the measurement is performed using a device to which an interface (manufactured by Nikkaki Co., Ltd.) that outputs the number distribution and volume distribution and a PC9801 personal computer (manufactured by NEC) are connected. An electrolytic solution is used for this measurement, and as the electrolytic solution, primary sodium chloride is used and 1% NaCl is used.
Prepared aqueous solution, for example, ISOTON R-
II (Made by Coulter Scientific Japan)
Can be used.

The measuring method is as follows:
0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 150 ml,
Further, 2 to 20 mg of the measurement sample is added. The electrolytic solution in which the sample is suspended is dispersed by an ultrasonic disperser for about 1 to 3 minutes, and the volume and the number of toner particles of 2 μm or more are measured by the Coulter Multisizer using a 100 μm aperture as an aperture. The distribution and the number distribution are calculated. Then, the volume-based mass average particle diameter obtained from the volume distribution is obtained. Since the value of the mass volume average particle diameter and the value of the volume average particle diameter are almost the same, this mass volume average particle diameter can be used as the value of the volume average particle diameter.

In the measurement of the volume average particle diameter of the fine particles in the toner, a trace amount of surfactant is added to 100 g of pure water to add 2 to 10 g of the toner, and an ultrasonic disperser (ultrasonic homogenizer) is used. ) For 10 minutes, and then the above fine particles are separated from the toner particles by a centrifuge or the like. In the case of magnetic toner, a magnet can also be used.
The separated dispersion is measured for 90 seconds with one measurement.

The particle size when the fine particles containing zinc oxide are formed as an agglomerate is defined as the average particle size of the agglomerate. There is no problem that the fine particles exist not only in the state of primary particles but also in the state of aggregation of secondary particles. Whatever the state of aggregation, the form is not limited as long as it is present as an agglomerate in the contact area between the charging member and the photoconductor or in the charging area in the vicinity thereof to realize the function of assisting or promoting charging.

In addition to this, the release rate of fine particles is 5 to 90%.
Is preferred. If the release rate of fine particles is less than 5%, the supply amount to the photoconductor is insufficient and it is difficult to obtain sufficient chargeability, and if it is more than 90%, the amount of fine particles collected by simultaneous development cleaning is large. This is not preferable because the triboelectric chargeability and the developability of the toner deteriorate due to the accumulation of fine particles in the developing device.

The release rate of the fine particles is represented by the ratio of the number of zinc atoms in zinc oxide not contained in the toner particles to the sum of the number of carbon atoms contained in the toner particles and zinc atoms in the zinc oxide. It The above release rate is based on Japan
The measurement can be performed by the principle described on pages 65 to 68 of the Hardcopy 97 papers. Specifically, the toner particles are introduced into the plasma one by one, and from the obtained emission spectrum, the elements in the toner particles, the number of toner particles, the toner The particle size of the particles can be known, and the above liberation rate can be measured from this emission spectrum.

According to the above measuring method, the liberation rate of the fine particles containing zinc oxide can be obtained from the emission of carbon atoms, which are the constituent elements of the binder resin contained in the toner particles, and the emission of zinc atoms according to the following equation. .

[0138]

[Equation 1] In the above formula, “simultaneously emitted light” means emission of zinc atoms and emission within 2.6 msec from emission of carbon atoms, and emission of zinc atoms thereafter is emission of zinc atoms only. Also, the fact that carbon atoms and zinc atoms simultaneously emit light means that zinc atoms are synchronized with the toner particles, and emission of only zinc atoms is zinc (zinc oxide).
Are free from the toner particles.

The release rate can be measured by using a particle analyzer (PT1000: manufactured by Yokogawa Electric Co., Ltd.) utilizing an emission spectrum.

The specific measuring method is as follows. First, using helium gas containing 0.1% oxygen, measurement is performed in an environment of 23 ° C. and a humidity of 60%, and the toner sample is left in the same environment overnight to adjust the humidity. In the measurement, carbon atoms (measurement wavelength 247.860 nm, K
Measure the zinc atom (measurement wavelength 334.5 nm, use the recommended value for K factor) in channel 2 so that the number of emission of carbon atom is 1000 to 1400 times in one scan. The sample is sampled, and the scanning is repeated until the total number of carbon atom emission is 10,000 or more, and the number of emission is integrated. At this time, in the distribution in which the number of times of emission of carbon atoms is plotted on the vertical axis and the cube root voltage of carbon atoms is plotted on the horizontal axis, the distribution has one maximum and further, a distribution in which no valley exists Sampling and measurement. Then, based on this data, the noise cut level of all atoms is set to 1.50 V, and the liberation rate of fine particles containing zinc oxide is calculated using the above-described calculation formula.
In addition, it measured similarly in the below-mentioned Example.

When the fine particles are externally added to the toner particles, the release rate is adjusted by appropriately adjusting the amount of the fine particles added to the toner particles, the external addition strength (external addition time, stirring speed) and the like. It When the fine particles are internally added to the toner particles, in the pulverized toner, the amount of the fine particles to be added to the toner particles, the kneading strength, and the pulverization conditions are set, and in the polymerized toner, the amount of the fine particles added and the surface of the fine particles. This is achieved by appropriately adjusting the treatment and the like.

The fine particles are preferably transparent, white or light-colored fine particles because the fine particles transferred onto the transfer material are not noticeable as fog. The fine particles are preferably transparent, white or light-colored fine particles also in the sense that they do not interfere with the exposure light in the electrostatic latent image forming step.
More preferably, the transmittance of the fine particles for exposure light is 30.
% Or more is preferable.

In the present invention, the light transmittance of fine particles is measured by the following procedure. The transmittance is measured with one layer of fine particles fixed on a transparent film having an adhesive layer on one surface. The light is emitted from the vertical direction of the sheet, and the light transmitted to the back surface of the film is condensed to measure the light amount. The transmittance of the particles is calculated as the net amount of light from the difference in the amount of light when only the film is attached and when the fine particles are attached. Actually, it is measured using a 310T transmission densitometer manufactured by X-Rite.

Japanese Patent Application Laid-Open No. 9-111135 discloses a technique relating to a conductive white powder material in which the surface of white inorganic powder is coated with aluminum-doped zinc oxide powder. However, the basic concept in this publication relates to a moldable conductive polymer material obtained by dispersing a conductive white powder in an organic polymer. On the other hand, the present invention also controls the behavior in a special use mode in which the function of the fine particles themselves is utilized while being entangled with various materials (for example, materials constituting the charging member surface, the photosensitive member surface, the toner particle surface, etc.). Since the present invention relates to an electrophotographic system, the two are completely different inventions including not only the field of use but also the idea of technology.

Further, the fine particles containing zinc oxide are preferably present on the surface of the toner particles in a ratio of 0.3 or more per toner particle, more preferably 1.0 to 50. It is present at a rate of 0 pieces. If it is less than 0.3, the effect of improving the fluidity of the toner may be deteriorated, which is not preferable.

The presence or absence of the fine particles present on the surface of the toner particles and the ratio of the existence thereof can be obtained by directly observing the surface of the toner particles. That is, a toner containing fine particles is captured by an electron microscope (SEM) with 10 toner particles as one aggregate, and is present on the surface of each toner particle.
The number of individual fine particles having a peak indicating the presence of a zinc element and another element other than zinc is counted.

For the qualitative analysis of the elements, a qualitative analysis device attached to the SEM is used. By this method, measurement is performed on 10 aggregates (total of 100 toner particles), and the existence ratio of fine particles per 100 toner particles is calculated. The fine particles having a peak indicating the presence of a zinc element and another element other than zinc are fine particles containing zinc oxide and an element other than zinc by a prior composition analysis (for example, ICP, ESCA, etc.), or an element other than zinc. It is confirmed that the fine particles are particles in which zinc oxide (ZnO) containing is supported on the surface of the base particles, and a countermeasure is taken.

In order to allow the fine particles to exist on the surface of the toner particles, as described above, the content is appropriately adjusted so that the fine particles are present on the surface of the toner particles in the above proportion, and the fine particles are externally added to the toner particles. Good.

The fine particles containing zinc oxide are preferably contained in the toner in an amount of 0.2 to 10% by mass. If the content of the fine particles is less than 0.2 mass% with respect to the total amount of the toner, the toner particles are less likely to be loosened and cleaning failure is likely to occur, and in the case of a cleanerless image forming method, the insulating transfer residual toner may contact the contact charging member. It is possible to interpose a sufficient amount of fine particles for overcoming the charging inhibition due to the adhesion and mixing of the particles and for favorably charging the photoconductor at the contact area between the charging member and the photoconductor or in the charging area in the vicinity thereof. As a result, the charging property is lowered and charging failure occurs. On the other hand, if the content is more than 10% by mass, the amount of fine particles collected by the simultaneous cleaning during development becomes too large, and thus the charging ability of the toner in the developing portion,
Developability deteriorates, image density decreases and toner scatters.

Further, the content of the fine particles in the whole toner is preferably 1.5 to 5 mass%.

In general, in order to faithfully develop fine latent image dots for higher image quality, the toner preferably has a mass average particle diameter of 3 to 10 μm. In the case of a toner having a mass average particle diameter of less than 3 μm, the transfer residual toner on the photoconductor is increased due to a decrease in the transfer efficiency of the toner. When such a toner is applied to the contact charging process used in the present invention, the charging member is contaminated. Therefore, the effect of accelerating the charging by the fine particles is reduced. Further, in addition to the increase in the surface area of the toner as a whole, the fluidity and agitation property of the powder are lowered, and it becomes difficult to uniformly triboelectrically charge the individual toner particles. However, it is not preferable as the toner used in the present invention because it tends to cause image defects due to factors other than the charging property. Further, when the mass average particle diameter of the toner exceeds 10 μm, scatter easily occurs in characters and line images, and it is difficult to obtain high resolution. Further, as the resolution of the device becomes higher, the reproduction of one dot tends to deteriorate.

In the present invention, since the value of the mass average particle diameter of the toner and the value of the volume average particle diameter are almost the same, the value of the volume average particle diameter is the same as the value of the mass average particle diameter of the toner. It can be regarded as a value.

In the present invention, either magnetic or non-magnetic toner can be used, but the toner is preferably a magnetic toner containing magnetic iron oxide. If the toner itself has a magnetic force, it is possible to suppress the scattering of the toner in the developing device by the magnet contained in the toner carrier, and the toner ejected from the charging process part in the developing process by the magnetic force. Is also preferable because the recoverability of is improved. Further, the average circularity of the toner is 0.970 or more, and the magnetic strength of the toner in the magnetic field of 79.6 kA / m (1000 Oersted) is 10 to 50 Am ² / kg.
(Emu / g) is preferable in order to reduce the amount of transfer residual toner and fog and maintain good chargeability.

Magnetic materials that can be contained in the magnetic toner used in the present invention include iron oxides such as magnetite, maghemite and ferrite, and iron oxides containing other metal oxides; metals such as Fe, Co and Ni; Alternatively, these metals and Al, Co, Cu, Pb, Mg, Ni, Sn,
Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, T
Examples thereof include alloys with metals such as i, W and V, and mixtures thereof.

Specifically, as the magnetic material, tetra-trioxide is used.
Iron (Fe₃O_Four), Ferric oxide (γ-Fe)₂O₃),iron oxide
Zinc (ZnFe₂O_Four), Yttrium iron oxide (Y₃Fe_Five
O₁₂), Cadmium iron oxide (CdFe₂O_Four), Iron oxide
Dolinium (Gd₃Fe_FiveO₁₂), Iron oxide copper (CuFe₂
O_Four), Iron oxide lead (PbFe)₁₂O₁₉), Iron oxide nickel
(NiFe₂O_Four), Iron neodymium oxide (NdFe₂O₃),
Barium iron oxide (BaFe₁₂O₁₉), Iron oxide magnesium
Mu (MgFe₂O_Four), Iron manganese oxide (MnFe
₂O_Four), Lanthanum iron oxide (LaFeO₃) Like magnetism
Iron oxide; Iron powder (Fe); Cobalt powder (Co); and Ni
Kell powder (Ni) may be used. The above magnetic materials alone
Or two or more kinds in combination. Above all
Magnetic iron oxide can be preferably used. Particularly suitable magnet
The conductive material is a fine powder of ferrosoferric oxide or γ-iron sesquioxide.
It The content of the magnetic substance is 100 parts by mass of the binder resin.
10 to 200 parts by mass of the magnetic material, preferably 20 to 15
It is 0 part by mass. In addition, magnetic iron oxide is used as a coloring agent.
It is also preferable because it has an effect.

The average circularity in the present invention is used as a simple method for quantitatively expressing the shape of particles. In the present invention, a flow type particle image analyzer "FPIA-1000" manufactured by Toa Medical Electronics is used. The circularity (a _i ) of each particle measured for a group of particles having an equivalent circle diameter of 3 μm or more is determined by the following formula (1), and further measured as shown by the following formula (2). A value obtained by dividing the sum of circularity of all particles by the total number of particles (m) is defined as the average circularity (a).

[0157]

[Equation 2]

[0158]

[Equation 3]

[0159] The measuring device "FPIA-1000" used in the present invention was used after calculating the circularity of each particle.
In calculating the average circularity, the particles are divided into 61 classes by dividing the circularity 0.40 to 1.00 according to the circularity obtained, and the average circularity is calculated using the center value and frequency of the division points. Method. However, the error from the average circularity values calculated by this calculation method is very small, and is substantially negligible. In the present invention, for the reasons of data handling such as shortening of calculation time and simplification of calculation calculation formula, the concept of the calculation formula which directly uses the circularity of each particle described above is used and partially changed. You may use such a calculation formula.

The measuring means is as follows. 5 mg of toner in 10 ml of water containing 0.1 mg of surfactant
To prepare a dispersion liquid, and ultrasonic waves (20 KHz, 5
(0 W) is irradiated to the dispersion for 5 minutes to adjust the dispersion concentration to 5000
Measured with the above device as ~ 20,000 / μl, 3μ
The average circularity of particles having a circle equivalent diameter of m or more is calculated.

The average circularity in the present invention is an index of the degree of unevenness of the toner, and shows 1.000 when the toner is a perfect sphere, and the more the surface shape becomes complicated, the smaller the circularity becomes.

The reason why the circularity is measured only for the particle group having the equivalent circle diameter of 3 μm or more in this measurement is 3 μm.
This is because the particle group having an equivalent circle diameter of less than m includes a large number of particles of the external additive that exist independently of the toner particles, and the circularity of the toner particle group cannot be accurately estimated due to the influence thereof. .

In the present invention, the magnetic toner is magnetized with an external magnetic field of 79.6 k at room temperature of 25 ° C. using a vibrating magnetometer VSM P-1-10 (manufactured by Toei Industry Co., Ltd.).
It is a value measured in A / m.

In the present invention, the differential scanning calorimeter (D
In the DSC curve measured by SC), the endothermic main peak temperature at the time of temperature increase is preferably in the range of 60 to 140 ° C., more preferably in the range of 60 to 120 ° C., particularly preferably in the toner, and the heat generation at the time of lowering the temperature. It is particularly preferable that the main peak temperature is preferably in the range of 60 to 150 ° C, more preferably 60 to 130 ° C.

In the DSC measurement, for example, DSC-7 manufactured by Perkin Elmer Co. can be used. The amount of sample used for measurement is about 10 to 15 mg in the case of a toner sample.
To use.

The measuring method is ASTM D3418-82.
Carry out according to. The DSC curve used in the present invention has a temperature rate of 10 ° C./min after the temperature is raised once and a previous history is taken.
The DSC curve measured when the temperature is lowered or raised in the temperature range of 0 to 200 ° C. is used.

As the colorant used for the toner, conventionally known dyes and / or pigments can be used. Examples of the colorant include carbon black, phthalocyanine blue, peacock blue, permanent red, lake red, rhodamine lake, hunter yellow, permanent yellow, and benzidine yellow. The content of the colorant is 0.1 to 20 parts by mass, and preferably 0.5 to 100 parts by mass of the binder resin.
20 parts by mass, preferably 12 parts by mass or less, and more preferably 0.5 to 9 parts by mass in order to improve the transparency of the OHP film on which the toner image is fixed.

The toner used in the present invention preferably contains the following inorganic fine powder in addition to the above-mentioned fine particles. As the inorganic fine powder, those having an average primary particle diameter of 4 to 80 nm as a fluidizing agent and a transfer aid are preferably added to the toner. The above-mentioned inorganic fine powder is added to improve the fluidity of the toner, to make the triboelectric charge amount of the toner particles uniform and to improve the transfer property. It is also a preferable mode to add functions such as adjusting the amount and improving environmental stability.

When the average primary particle size of the inorganic fine powder is too large, or when the inorganic fine powder having a particle size of 80 nm or less is not added, the amount of the transfer residual toner increases and the stable and good charging property is obtained. Is difficult to obtain.
Further, good fluidity of the toner is not obtained, charge impartment to the toner particles is likely to be non-uniform, and problems such as increased fog, reduced image density, and toner scattering cannot be avoided. on the other hand,
When the average primary particle size of the inorganic fine powder is too smaller than 4 nm, the agglomeration of the inorganic fine powder is enhanced, and the aggregate is not primary particles but a solid agglomerate having a strong agglomeration which is hard to be broken by crushing treatment and has a wide particle size distribution. As a result, image defects are likely to occur due to development of aggregates or damage to the photoconductor, the toner carrier, and the like. In order to make the triboelectric charge amount distribution of the toner particles more uniform, the average primary particle diameter of the inorganic fine powder is more preferably 6 to 70 nm.

In the present invention, the average primary particle diameter of the inorganic fine powder is a photograph of the toner magnified by a scanning electron microscope, and the inorganic fine powder is analyzed by an elemental analysis means such as XMA attached to the scanning electron microscope. It is possible to determine the number average diameter by measuring 100 or more primary particles of the inorganic fine powder adhering to or detaching from the toner surface while comparing with the photograph of the toner mapped by the element contained in I can.

As the inorganic fine powder used in the present invention,
Silica, alumina, titanium oxide, or their composite oxide can be used. For example, both silica, so-called silica fine powder, so-called dry method produced by vapor phase oxidation of silicon halide or so-called fumed silica, and so-called wet silica produced from water glass and the like are both. It can be used, but there are few silanol groups on the surface and inside the silica fine powder.
Dry silica having less production residue such as ₂ O and SO ^3- is preferable. Further, in the case of dry silica, it is possible to obtain a composite fine powder of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the manufacturing process. Also includes.

The amount of the inorganic fine powder having an average primary particle diameter of 4 to 80 nm added is 0.1 to 3.0% by mass based on the toner.
If the addition amount is less than 0.1% by mass, the effect is not sufficient, and if it exceeds 3.0% by mass, the fixing property is deteriorated.

The inorganic fine powder is preferably hydrophobized from the viewpoint of characteristics under high temperature and high humidity environment. When the inorganic fine powder mixed with the toner absorbs moisture, the triboelectric charge amount of the toner is remarkably reduced, and the toner tends to scatter.

As the treatment agent for the hydrophobizing treatment, a treatment agent such as silicone varnish, various modified silicone varnishes, silicone oils, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds and organic titanium compounds are used. You may process it individually or in combination.

Among them, those treated with silicone oil are preferable, and more preferably those treated with silicone oil at the same time as or after the hydrophobic treatment of the inorganic fine powder are subjected to triboelectrification of toner even in a high humidity environment. It is good for keeping the amount high and preventing toner scattering.

The conditions for treating the inorganic fine powder include, for example, a silylation reaction as a first-step reaction to eliminate silanol groups by a chemical bond, and then a second step reaction to form a hydrophobic thin film on the surface with silicone oil. can do.

The above silicone oil preferably has a viscosity at 25 ° C. of 10 to 200,000 mm ² / s, more preferably 3,000 to 80,000 mm ² / s. When the viscosity of the silicone oil is less than 10 mm ² / s, the inorganic fine powder is not stable, and the image quality tends to deteriorate due to heat and mechanical stress. 200,000 m
If it exceeds m ² / s, uniform treatment tends to be difficult.

As the silicone oil to be used, for example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, fluorine modified silicone oil and the like are particularly preferable. As a method of treating the silicone oil, for example, the inorganic fine powder treated with a silane compound and the silicone oil may be directly mixed by using a mixer such as a Henschel mixer, or the inorganic fine powder may be sprayed with the silicone oil. Any method may be used. Alternatively, a method may be used in which after dissolving or dispersing silicone oil in a suitable solvent, silica fine powder is added and mixed to remove the solvent. The method using a sprayer is more preferable in that the formation of aggregates of the inorganic fine powder is relatively small.

The amount of silicone oil to be treated was 1 for inorganic fine powder.
1 to 23 parts by weight, preferably 5 to 20 parts by weight with respect to 00 parts by weight
Good mass parts. If the amount of silicone oil is too small, it may not be possible to impart good hydrophobicity to the inorganic fine powder, and if it is too large, problems such as fog may occur.

The average primary particle diameter used in the present invention is 4 to.
The 80 nm inorganic fine powder preferably has a specific surface area within the range of ²⁰ to 250 m ² / g due to nitrogen adsorption measured by the BET method. The specific surface area is obtained according to the BET method by using a specific surface area measuring device Autosorb 1 (manufactured by Yuasa Ionics) to adsorb nitrogen gas on the sample surface and calculating the specific surface area using the BET multipoint method.

In the toner used in the present invention, it is preferable that a charge control agent is blended (internally added) to the toner particles.

Examples of the positive charge control agent include modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate. They can be used alone or in combination of two or more. Among these,
Charge control agents such as nigrosine compounds and quaternary ammonium salts are particularly preferably used. Further, a monomer homopolymer or a copolymer with a polymerizable monomer such as styrene, acrylic acid ester and methacrylic acid ester as described above can be used as a positive charge control agent. The charge control agent also has a function as (all or part of) a binder resin.

As the negative charge control agent, for example, organic metal complexes and chelate compounds are effective, and there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids and aromatic dicarboxylic acid type metal complexes.
Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids, metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

The above-mentioned charge control agent (which does not act as a binder resin) is preferably used in the form of fine particles. In this case, the number average particle size of this charge control agent is
Specifically, it is preferably 4 μm or less (further, 3 μm or less). When internally added to the toner, such a charge control agent is used in an amount of 0.1 to 20 parts by mass (preferably 0.2 to 10 parts by mass) with respect to 100 parts by mass of the binder resin.

The toner of the present invention can be manufactured by a pulverization method or a polymerization method. First, a pulverization method will be exemplified. Binder resin, magnetic material, release agent, charge control agent, colorant, and other components necessary for toner and other additives are thoroughly mixed with a mixer such as a Henschel mixer or a ball mill, and then heated rolls, kneaders, and extruders. Melt and knead using a heat kneader such as Ruder to disperse or dissolve other toner materials such as magnetic material in the resin to make them compatible with each other, cool and solidify, pulverize, classify, if necessary Surface treatment can be performed to obtain toner particles. Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency. In the crushing process, a method using a known crushing device such as a mechanical impact type or a jet type can be used.

Examples of the binder resin used in the toner of the present invention include homopolymers of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene and the like, and substitution products thereof; styrene-p-chlorostyrene copolymerization Copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethacryl copolymer, styrene-acrylonitrile copolymer Polymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer Styrenic copolymers such as polymers Polyvinyl chloride, phenol resin, natural resin modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, Examples thereof include polyvinyl butyral, terpene resin, coumarone indene resin, and petroleum-based resin.

A vinyl-based monomer is used as a comonomer for the styrene monomer of the styrene-based copolymer. Examples of vinyl monomers include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate. , Ethyl methacrylate,
A monocarboxylic acid having a double bond such as butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide or a substituted product thereof;
For example, a dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate, and dimethyl maleate and its substituted products; for example, vinyl esters such as vinyl chloride, vinyl acetate, vinyl benzoate; for example, vinyl. Examples thereof include vinyl ketones such as methyl ketone and vinyl hexyl ketone; for example, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether. These are used alone or in combination of two or more.

As the crosslinking agent, a compound having two or more polymerizable double bonds is mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; for example, ethylene glycol diacrylate and ethylene glycol. Dimethacrylate, 1,
A carboxylic acid ester having two double bonds such as 3-butanediol dimethacrylate; a divinyl compound such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone; and a compound having three or more vinyl groups; Alternatively, they are used as a mixture.

Further, the binder resin used in the present invention may be a polymer or copolymer crosslinked with a crosslinking monomer. Examples of the aromatic divinyl compound include divinylbenzene and divinylnaphthalene; examples of the diacrylate compounds linked by an alkyl chain include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate and 1,4-butanediol diamine. Acrylate, 1,5-pentanediol diacrylate, 1,6 hexanediol diacrylate, neopentyl glycol diacrylate, and the above compounds in which the acrylate is replaced with methacrylate; linked by an alkyl chain containing an ether bond Examples of diacrylate compounds include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate. , Polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate and the acrylates of the above compounds replaced with methacrylates; as diacrylate compounds linked by a chain containing an aromatic group and an ether bond. For example, polyoxyethylene (2)-
2,2-bis (4-hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,2-bis (4-hydroxyphenyl) propane diacrylate, and those obtained by replacing the acrylates of the above compounds with methacrylates are mentioned. Examples of the polyester type diacrylates include trade name MANDA (Nippon Kayaku Co., Ltd.).

Here, as a cross-linking agent, pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate,
Tetramethylolmethane tetraacrylate, oligoester acrylates, and compounds obtained by replacing the acrylates of the above compounds with methacrylates; triallyl cyanurate, triallyl trimellitate and the like can be mentioned.

These cross-linking agents are used as the other monomer component 10
0 to 10 parts by mass, preferably 0.01 to 10 parts by mass,
More preferably, 0.03 to 5 parts by mass can be used. Among the crosslinkable monomers, those that are preferably used in the resin for toner from the viewpoints of fixing property and anti-offset property include aromatic divinyl compounds (particularly divinylbenzene), di-chains linked by a chain containing an aromatic group and an ether bond. Acrylate compounds may be mentioned.

The binder resin used in the present invention is preferably a vinyl resin, a polyester resin, an epoxy resin, or the like, more preferably a vinyl resin and a polyester resin. Further, in the present invention, a vinyl monomer homopolymer or copolymer, polyester, polyurethane, epoxy resin, polyvinyl butyral, rosin,
A modified rosin, a terpene resin, a phenol resin, an aliphatic or alicyclic hydrocarbon resin, an aromatic petroleum resin, or the like can be used by mixing with the binder resin described above, if necessary. When two or more kinds of resins are mixed and used as a binder resin, it is preferable to mix resins having different molecular weights at an appropriate ratio.

As the physical properties of the vinyl resin used as the binder resin, the glass transition temperature is preferably 45 to 80 ° C., more preferably 55 to 70 ° C., and in the molecular weight distribution measured by gel permeation chromatography (GPC), Number average molecular weight (Mn) is 2,500 to 50,0
00, the mass average molecular weight (Mw) is 10,000 to 1.0
It is preferably 0,000.

The glass transition point (Tg) of the binder resin was measured under the following conditions using a differential thermal analyzer (DSC measuring device) and DSC-7 (manufactured by Perkin Elmer).

[0195]   Sample: 5 to 20 mg, preferably 10 mg   Temperature curve: temperature increase I (20 ° C. → 180 ° C., temperature increase rate 10 ° C./min.)             Temperature drop I (180 ° C → 10 ° C, temperature drop rate 10 ° C / min.)             Temperature rise II (10 ° C → 180 ° C, temperature rise rate 10 ° C / min.) The measured value is Tg measured at the temperature rise II.

Measurement method: A sample is placed in an aluminum pan and an empty aluminum pan is used as a reference. The crossing point between the line at the midpoint of the base line before and after the appearance of the endothermic peak and the differential heat curve is defined as the glass transition point Tg.

Regarding the molecular weight of the binder resin by GPC, the solution obtained by dissolving the toner in THF (tetrahydroxyfuran) by allowing it to stand at room temperature for 24 hours was filtered through a solvent-resistant membrane filter having a pore size of 0.2 μm. The sample solution can be used as a sample solution, and the measurement can be performed under the following conditions. For sample preparation, the concentration of the soluble component in THF was 0.4-
The amount of THF is adjusted to be 0.6% by mass.

Device: High-speed GPC HLC8120
GPC (manufactured by Tosoh Corporation) column: Shodex KF-801, 802, 80
7, 804, 805, 806, and 807 (manufactured by Showa Denko KK) Eluent: THF Flow rate: 1.0 ml / min Oven temperature: 40.0 ° C. Sample injection amount: 0.10 ml

When calculating the molecular weight of a sample,
Standard polystyrene resin (TSK standard polystyrene F-850, F-450, F-28 manufactured by Tosoh Corporation)
8, F-128, F-80, F-40, F-20, F-
10, F-4, F-2, F-1, A-5000, A-2
500, A-1000, A-500) can be used.

The molecular weight of the toner can be arbitrarily changed depending on the binder resin used and the kneading conditions when it is produced by the pulverization method. Further, in the polymerization method, it can be arbitrarily changed depending on the combination of the type and amount of the initiator and the crosslinking agent used. It can also be adjusted by using a chain transfer agent or the like.

The binder resin made of a vinyl polymer or copolymer can be synthesized, for example, by the following method. As a synthesis method, a bulk polymerization method, a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method can be used.

For example, when a carboxylic acid monomer or an acid anhydride monomer is used, it is preferable to use the bulk polymerization method or the solution polymerization method because of the nature of the monomer. A vinyl copolymer can be obtained by a bulk polymerization method or a solution polymerization method using a monomer such as a dicarboxylic acid, a dicarboxylic acid anhydride, or a dicarboxylic acid monoester. In the solution polymerization method, the dicarboxylic acid and dicarboxylic acid monoester units can be partially dehydrated by devising the distillation conditions when the solvent is distilled off. Further, the vinyl-based copolymer obtained by the bulk polymerization method or the solution polymerization method is subjected to heat treatment, so that it can be further dehydrated. It is also possible to partially esterify the acid anhydride with a compound such as an alcohol. On the contrary, the thus obtained vinyl-based copolymer can be partially hydrolyzed to form a dicarboxylic acid by ring closure of the acid anhydride group.

On the other hand, using a dicarboxylic acid monoester monomer, a vinyl copolymer obtained by a suspension polymerization method or an emulsion polymerization method is dehydrated from an anhydride by dehydration by heat treatment and ring opening by hydrolysis treatment. Obtainable. The vinyl copolymer obtained by the bulk polymerization method or the solution polymerization method is dissolved in a monomer, and then by a suspension polymerization method or an emulsion polymerization method, a method of obtaining a vinyl polymer or a copolymer is used, A part of the acid anhydride can be opened to obtain a dicarboxylic acid unit. Another resin may be mixed in the monomer during the polymerization, and the obtained resin can be subjected to an acid anhydride treatment by a heat treatment and an esterification treatment by a ring-opening alcohol treatment of the acid anhydride by a weak alkaline water treatment.

Since the dicarboxylic acid and dicarboxylic acid anhydride monomers have strong alternating polymerizability, the following method is preferable in order to obtain a vinyl-based copolymer in which functional groups such as anhydride and dicarboxylic acid are randomly dispersed. one of. This is a method in which a vinyl-based copolymer is obtained by a solution polymerization method using a dicarboxylic acid monoester monomer, the vinyl-based copolymer is dissolved in the monomer, and a binder resin is obtained by a suspension polymerization method. In this method, all or the dicarboxylic acid monoester portion can be dealcoholized and ring-closed and dehydrated depending on the treatment conditions when the solvent is distilled off after the solution polymerization to obtain an acid anhydride. During suspension polymerization, the acid anhydride group undergoes ring opening by hydrolysis to give a dicarboxylic acid.

In the case of acid anhydride formation in the polymer, the infrared absorption of carbonyl shifts to a higher wave number side than that of the acid or ester, so that the production or disappearance of the acid anhydride can be confirmed. In the binder resin thus obtained, the carboxyl group, the anhydride group and the dicarboxylic acid group are uniformly dispersed in the binder resin, so that the toner can be imparted with good chargeability.

The following polyester resins are also preferable as the binder resin. Polyester resin is 45 ~ in all components
55 mol% is alcohol component, 55-45 mo
1% is the acid component. Alcohol components include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexane. Examples thereof include diols, neopentyl glycol, 2-ethyl 1,3-hexanediol, hydrogenated bisphenol A, bisphenol derivatives, diols, and polyhydric alcohols such as glycerin, sorbit and sorbitan.

Examples of the divalent carboxylic acid containing 50 mol% or more in all the acid components include benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and phthalic anhydride or their anhydrides; succinic acid, adipic acid, sebacic acid, Alkyl dicarboxylic acids such as azelaic acid or their anhydrides, and succinic acid substituted with an alkyl group or an alkenyl group having 6 to 18 carbon atoms or their anhydrides; fumaric acid, maleic acid, citraconic acid, itaconic acid Saturated dicarboxylic acid or its anhydride, and the like,
Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid and anhydrides thereof.

The alcohol component of the particularly preferred polyester resin is a bisphenol derivative, and the acid component is phthalic acid, terephthalic acid, isophthalic acid or its anhydride, succinic acid, n-dodecenylsuccinic acid or its anhydride, fumaric acid, And dicarboxylic acids such as maleic acid and maleic anhydride; and trimellitic acid or its tricarboxylic acid anhydride.

The toner containing the binder resin using the polyester resin obtained from these acid component and alcohol component has good fixability as a toner to which the heat roller fixing is applied in the image forming method of the present invention, and has good resistance. This is because it has excellent offset properties.

The acid value of the polyester resin is preferably 90.
mgKOH / g or less, more preferably 50 mgKOH / g
g or less, and the OH value of the polyester resin is preferably 50 mgKOH / g or less, more preferably 30 mgKO.
It is preferably H / g or less. This is because as the number of terminal groups of the molecular chain increases, the charging characteristic of the toner becomes more environmentally dependent.

Glass transition temperature of polyester resin (T
g) is preferably 50 to 75 ° C., more preferably 55 to 75 ° C.
The temperature is preferably 65 ° C., and in the molecular weight distribution of the polyester resin measured by GPC, the number average molecular weight (Mn) is preferably 1,500 to 50,000, more preferably 2,000 to 20,000, and the mass average. Molecular weight (M
w) is preferably 6,000 to 100,000, and more preferably 10,000 to 90,000.

Next, suspension polymerization will be exemplified as a polymerization method. A polymerizable monomer and a colorant, and if necessary, a polymerization initiator, a cross-linking agent, a charge control agent, a release agent, a plasticizer, a magnetic material, and other additives are homogenized, ball mills, colloid mills, and ultrasonic waves. A monomer system that is uniformly dissolved or dispersed by a disperser such as a disperser is suspended in an aqueous medium containing a dispersion stabilizer. The polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. It is also possible to add a polymerization initiator dissolved in a polymerizable monomer or a solvent immediately after granulation and before starting the polymerization reaction.

The polymerization temperature is 40 ° C. or higher, generally 50 to 9
Polymerization is carried out at a temperature of 0 ° C. When the polymerization is carried out within this temperature range, the release agent and waxes to be sealed inside are precipitated by phase separation and the encapsulation becomes more complete. In order to consume the remaining polymerizable monomer, it is possible to raise the reaction temperature to 90 to 150 ° C. at the end of the polymerization reaction.

The following are examples of the polymerizable monomer that constitutes the polymerizable monomer system. As the polymerizable monomer, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-
Styrene monomers such as ethylstyrene, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, Stearyl acrylate / acrylic acid 2-
Acrylic esters such as chloroethyl / phenyl acrylate, methyl methacrylate / ethyl methacrylate / n-propyl methacrylate / n-butyl methacrylate / isobutyl methacrylate / n-octyl methacrylate / dodecyl methacrylate / methacrylic acid 2- Examples thereof include methacrylic acid esters such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and other monomers such as acrylonitrile, methacrylonitrile, and acrylamide.

These monomers may be used alone or as a mixture. Among the above-mentioned monomers, it is preferable to use styrene or a styrene derivative alone or in combination with other monomers, from the viewpoint of developing characteristics and durability of the toner.

A resin may be added to the monomer for polymerization.
For example, a monomer is water-soluble and cannot be used because it is dissolved in an aqueous suspension to cause emulsion polymerization, an amino group, a carboxylic acid group, a hydroxyl group, a sulfonic acid group, a glycidyl group,
When it is desired to introduce a monomer component containing a hydrophilic functional group such as a nitrile group into the toner, a random copolymer, a block copolymer, a graft copolymer or the like of these and a vinyl compound such as styrene or ethylene is used. In the form of a united body, or a polycondensate of polyester, polyamide, etc.,
It can be used in the form of polyaddition polymers such as polyether and polyimine. When such a high molecular weight polymer containing a polar functional group is coexisted in the toner, the wax component is phase-separated, the inclusion becomes stronger, and the toner having good offset resistance, blocking resistance, and low temperature fixing property is obtained. Obtainable. When such a polymer having a polar functional group is used, its average molecular weight is preferably 5,000 or more. When it is 5,000 or less, particularly 4,000 or less, the present polymer is likely to concentrate near the surface, which is unfavorable since it tends to adversely affect the developability, blocking resistance and the like. As the polar polymer, polyester resin is particularly preferable.

Further, a resin other than the above may be added to the monomer system for the purpose of improving the dispersibility and fixing property of the material, the image characteristics, etc. Examples of the resin used include polystyrene and polyvinyltoluene. Homopolymers of styrene and its substitutes; styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-
Vinyl naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer Polymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer Polymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer Styrene-based copolymers such as coalesce; Methyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin,
Polyester resin, polyamide resin, epoxy resin, polyacrylic acid resin, rosin, modified rosin, tempel resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin and the like can be used alone or in combination. The addition amount of these resins is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the monomer. If it is less than 1 part by mass, the effect of addition is small, while if it is added in an amount of 20 parts by mass or more, it becomes difficult to design various physical properties of the polymer toner.

As the polymerization initiator, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile) is used. Nitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile,
Azo-based or diazo-based polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t- Examples thereof include peroxide-based polymerization initiators such as butyl peroxy 2-ethylhexanoate.

A crosslinking agent may be added, and the preferable addition amount is 0.001 to 15% by mass. As the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used, and examples thereof include aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and the like; for example, ethylene glycol diacrylate, ethylene glycol dimethacrylate, Carboxylic acid ester having two double bonds such as 1,3-butanediol dimethacrylate; Divinyl compound such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone;
And a compound having three or more vinyl groups; used alone or as a mixture.

As the dispersion stabilizer, a surfactant or organic
Inorganic dispersants can be used, and among them, inorganic dispersants are preferred from the viewpoint of dispersion stability. Examples of the inorganic dispersant include calcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, and other polyvalent metal salts of phosphate, calcium carbonate, carbonates such as magnesium carbonate, inorganic salts such as calcium metasilicate, calcium sulfate, and barium sulfate. Examples thereof include inorganic oxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite, and alumina. The inorganic dispersant is 0.2 to 20 with respect to 100 parts by mass of the polymerizable monomer.
Although it is desirable to use a mass part alone, it is difficult to generate ultrafine particles, but it is rather difficult to atomize the toner, so 0.001 to 0.1 part by mass of a surfactant may be used together. Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, potassium stearate and the like.

Examples of the releasing agent include petroleum waxes such as paraffin wax, microcrystalline wax, petrolactam and derivatives thereof, montan wax and derivatives thereof, hydrocarbon wax and derivatives thereof by Fischer-Tropsch method, and polyolefins represented by polyethylene. Natural waxes such as wax and its derivatives, carnauba wax, candelilla wax and its derivatives, and the like include oxides, block copolymers with vinyl monomers, and graft modified products. Moreover,
Fatty acids such as higher aliphatic alcohols, stearic acid, palmitic acid, or their compounds, acid amide wax, ester wax, ketone, hydrogenated castor oil and its derivatives, plant wax, animal wax, etc. ℃ or more and 110 ℃ or less, further 50
Those having a temperature of not less than 90 ° C and not more than 90 ° C are preferable. The content of the release agent is 0.5 to 50 mass% with respect to the entire toner.
Is preferred. If the content is less than 0.5% by mass, the low-temperature offset suppressing effect is poor, and if it exceeds 50% by mass, the long-term storability may deteriorate.

Whether the toner used in the present invention is produced by a pulverization method or a polymerization method, the fine particles may be internally added to the toner particles by adding the fine particles to a binder resin (in the case of suspension polymerization, The polymerizable monomer that constitutes the binder resin), the colorant and other additives are mixed to obtain toner particles. on the other hand,
When the fine particles are externally added to the toner particles, the toner particles are obtained by the above method, and then the fine particles are mixed with the other external additives into the toner particles to obtain the toner.

Next, the image forming method and the image forming apparatus of the present invention will be described. The image forming method of the present invention,
(A) a charging step of charging a photoreceptor, which is an image carrier,
(B) an electrostatic latent image forming step of forming an electrostatic latent image on a charged photoconductor, and (c) a toner carried on a toner carrier is transferred to the electrostatic latent image to form a toner image. And a transfer step of electrostatically transferring the toner image formed on the photoconductor in the developing step (d) to the transfer material.

The photoconductor used in the present invention is characterized by being a so-called amorphous silicon photoconductor having a conductive support and a photoconductive layer made of a non-single-crystal material having silicon atoms as a matrix. Further, the photoreceptor preferably further has a surface layer formed of a non-single crystalline hydrogenated carbon film. By using a non-single crystal hydrogenated carbon film as the surface layer, the hardness of the surface of the photoconductor can be increased, and the wear amount of the photoconductor surface due to durable use is reduced, leading to high durability.

Further, the film thickness of the surface layer of the photoreceptor used in the present invention is 0.01 to 10 μm, preferably 0.1 to 1 μm in view of the wear amount of the surface layer and the life of the electrophotographic apparatus. Range is desirable. If the thickness of the surface layer is 0.01 μm or less, the mechanical strength may be impaired, and if it is 10 μm or more, the residual potential on the surface of the photoconductor becomes high, and optimum potential setting and sensitivity may not be obtained. Not preferable.

In the present invention, the surface layer made of the amorphous hydrogenated carbon film has the following formula (3).

[0227]

## EQU00004 ## Silicon atom content rate (%) = (number of silicon atoms / (number of silicon atoms + number of carbon atoms)). Times.100 (3) The silicon atom content rate defined by (3) is 0.01% or less. Represents a surface layer.

The silicon atom content (number of atoms) of the surface layer was measured by preparing a surface layer deposited on a 7059 glass substrate by 0.5 μm as a sample for measuring the carbon content. Is a value obtained by respectively measuring the number of carbon atoms and silicon atoms by SIMS, and the silicon atom content rate is calculated from this value and the above equation (3).

Further, the amount of hydrogen contained in the amorphous hydrogenated carbon film constituting the surface layer is H / (C + H) of 41 to 41.
60%, preferably 45 to 55% is preferable. The amount of hydrogen is 4
If it is 0% or less, electrophotographic characteristics are deteriorated, it is difficult to secure a sufficient potential difference in the developing step, and image defects such as fog images may occur, which is not preferable in some cases.
If it exceeds%, the densification of the film may be impaired, the mechanical strength may be impaired, and the surface layer may be abraded, which is not preferable.

The above hydrogen content can be obtained by preparing a surface layer sample on a silicon wafer in order to measure the hydrogen content of the surface layer, and measuring the hydrogen content by IR with respect to this surface layer sample. Also, by IR measurement, C
The peaks of -C and C-H bonds are detected, and the area ratio of the peaks is assigned to each of the C-C bond part with 2 C atoms and the C-H bond part with 1 each, and multiplied by each area ratio. Then, the amount of hydrogen was calculated from the following formula (4).

[0231]

[Equation 5]     Hydrogen amount (%) = (number of hydrogen / (number of carbon + number of hydrogen)) × 100 ... (4)

Hereinafter, the light receiving member as the photosensitive member used in the present invention will be described in detail with reference to the drawings. Figure 2 (A)
And (B) are examples of schematic cross-sectional views of the light receiving member used in the present invention. FIG. 2 (A) shows a single-layer type light receiving member having a single layer in which the photoconductive layer is not functionally separated, and FIG. 2 (B) shows that the photoconductive layer is separated into a charge generation layer and a charge transport layer. It is a function-separated type light-receiving member.

The light receiving member shown in FIG. 2A is made of an amorphous silicon (hereinafter sometimes referred to as "a-Si") material, and is made of a conductive substrate 10 such as aluminum.
1 and a charge injection blocking layer 102, a photoconductive layer 103, and a surface layer 104, which are sequentially stacked on the surface of the conductive substrate 101. Here, the charge injection blocking layer 102 is the conductive substrate 1
It prevents the injection of charges from 01 to the photoconductive layer 103, and is provided as necessary. A known material can be used as the material of the charge injection blocking layer 102, and the thickness is set as necessary. The photoconductive layer 103 is made of an amorphous material containing at least silicon atoms and exhibits photoconductivity. Further, the surface layer 104 is a film (a−) made of an amorphous material containing carbon atoms and hydrogen atoms.
C: H film) 3, which has the ability to hold a visible image in an electrophotographic apparatus.

Hereinafter, FIG. 2B will be described assuming that the charge injection blocking layer 102 is provided, except that the effect differs depending on the presence or absence of the charge injection blocking layer 102.

In the a-Si based light receiving member shown in FIG. 2B, the photoconductive layer 103 has a charge transport layer 106 made of an amorphous material containing at least silicon atoms and carbon atoms.
It is a function-separated type light-receiving member having a structure in which a charge generation layer 105 made of an amorphous material containing at least silicon atoms is sequentially laminated. When the light receiving member is irradiated with light, carriers mainly generated in the charge generation layer 105 pass through the charge transport layer 106 and reach the conductive substrate 101.

Each layer constituting the light receiving member was formed by an RF plasma CVD method using a high frequency power source (hereinafter referred to as "RF-PCV").
It can be formed by a chemical vapor deposition method such as a VHF plasma CVD method using a VHF power source (hereinafter referred to as “VHF-PCVD method”).

FIG. 3 is a diagram schematically showing an example of a light receiving member depositing apparatus using the RF-PCVD method. This apparatus is roughly classified into a deposition apparatus 2100, a source gas supply apparatus 2200, and a reaction vessel 2110 in the deposition apparatus 2100.
It is composed of an exhaust device (not shown) for decompressing the inside. Inside the reaction vessel 2110, a cylindrical film-forming substrate 2112 connected to the ground, a heater 2113 for heating the cylindrical film-forming substrate 2112, and a raw material gas introduction pipe 2114 are installed, and a high frequency wave is passed through a high frequency matching box 2115. The power supply 2120 is connected.

The source gas supply device 2200 is made of SiH ₄ ,
Source gas cylinders 2221 to 2226 such as H ₂ , CH ₄ , NO, B ₂ H ₆ and CF ₄ and valves 2231 to 2236, 22
41 to 2246, 2251 to 2256 and mass flow controllers 2211 to 2216, and each source gas cylinder 2221 to 2226 is connected to a gas introduction pipe 2114 in the reaction vessel 2110 via each valve 2260.

The cylindrical film-forming substrate 2112 is installed on the conductive pedestal 2123 to be connected to the ground.

An example of the procedure of the method for forming the light receiving member using the apparatus shown in FIG. 3 will be described below. Reaction vessel 21
A cylindrical film-forming substrate 2112 serving as a conductive substrate
Is installed, and the inside of the reaction vessel 2110 is exhausted by an exhaust device (for example, a vacuum pump) not shown. Subsequently, the temperature of the cylindrical film-forming substrate 2112 is set to 2 by the heating heater 2113.
Control to the desired temperature from 0 ° C to 500 ° C. Next, in order to flow the raw material gas for forming the light receiving member into the reaction vessel 2110, first, the valve 2231 of the raw material gas cylinder is used.
~ 2236 and the leak valves 2117 of the reaction vessels are confirmed to be closed, and the inflow valves 2241 to 22
46, outflow valves 2251 to 2256, auxiliary valve 22
After confirming that 60 is open, main valve 2
118 is opened and the reaction vessel 2110 and the gas supply pipe 21 are opened.
Evacuate 16.

After that, the reading of the vacuum gauge 2119 was 0.67.
When the pressure reaches mPa, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed. Then the valve 2231
Up to 2236 are opened, each gas is introduced from the gas cylinders 2221 to 2226, and each gas pressure is adjusted to ² kg / cm ² by the pressure adjusters 2261 to 2266. Next, the inflow valves 2241 to 2246 are gradually opened to introduce each gas into the mass flow controllers 2211 to 2216.

After the film formation preparation is completed by the above procedure, a charge injection blocking layer is formed on the cylindrical film formation substrate 2112, if necessary, and then a photoconductive layer is formed. In this specification, only formation of the photoconductive layer will be described. When the cylindrical film-forming substrate 2112 reaches a desired temperature, necessary ones of the outflow valves 2251 to 2256 and the auxiliary valve 2260 are gradually opened, and a desired source gas is supplied from each of the gas cylinders 2221 to 2226. It is introduced into the reaction vessel 2110 via the gas introduction pipe 2114.
Next, each mass flow controller 2211-2216
Is adjusted so that each source gas has a desired flow rate. At that time, the opening of the main valve 2118 is adjusted while observing the vacuum gauge 2119 so that the inside of the reaction vessel 2110 has a desired pressure of 133.3 Pa or less. Reaction vessel 211
When the internal pressure of 0 is stable, turn the high frequency power supply 2120 to 1
Set to the desired power of ~ 450 MHz, for example 13.
High-frequency matching box 2 with high-frequency power of 56MHz
It is supplied to the cathode electrode 2111 through 115 to generate high frequency glow discharge. Each source gas introduced into the reaction vessel 2110 is decomposed by this discharge energy,
A photoconductive layer containing desired silicon atoms as a main component is deposited on the cylindrical film-forming substrate 2112. After the layer having a desired film thickness is formed, the supply of the high frequency power is stopped, the outflow valves 2251 to 2256 are closed to stop the inflow of the source gases into the reaction vessel 2110, and the formation of the photoconductive layer is completed. . The photoconductive layer may have a known composition and film thickness as long as it is made of an amorphous material having silicon atoms as a matrix.

When forming a surface layer on the photoconductive layer,
Basically, the above operation may be repeated. At that time, surface layer
The film forming gas for 104 is CH_Four, C₂H₆, C₃H₈,
C_FourH _TenSuch as gas and hydrocarbon that can be gasified are effective
It is mentioned as being used. Also, these carbon supplies
The raw material gas for supply is H if necessary.₂, He, Ar, Ne
You may use it after diluting it with gas such as.

FIG. 4 is a diagram schematically showing an example of a photoreceptive member deposition apparatus by the VHF-PCVD method. This apparatus is configured by replacing the deposition apparatus 2100 shown in FIG. 3 with the deposition apparatus 3100 shown in FIG. VHF-PC
Formation of a deposited film by this apparatus using the VD method can be performed as follows.

First, the conductive support 3112 is installed in the reaction vessel 3111. The support 3112 is rotated by the driving device 3120, the inside of the reaction container 3111 is exhausted through the exhaust pipe 3121 by an exhaust device (not shown) (for example, a diffusion pump), and the pressure inside the reaction container 3111 is 1.33 × 10.
Adjust to ^-5 Pa or less. Then, the temperature of the conductive support 3112 is set to 50 to 5 by the support heating heater 3113.
It is heated and maintained at a predetermined temperature of 00 ° C.

A source gas for forming a deposited film is supplied to the reaction vessel 311.
In order to make it flow into 1, the gas cylinder valve 2 in FIG.
231-2236, leak valve of reaction vessel (not shown)
Make sure that each is closed, and inflow valve 2
After confirming that the valves 241-2246, the outflow valves 2251-2256, and the auxiliary valve 2260 are respectively opened, the main valve (not shown) is opened and the reaction vessel 31 is opened.
11. Exhaust the inside of 11 and the gas pipe. Then, when the reading of the vacuum gauge (not shown) reaches about 6.65 × 10 ⁻⁴ Pa, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed.

Thereafter, the valves 2231 to 2236 are opened to introduce the respective gases from the gas cylinders 2221 to 2226,
Each gas pressure is set to 2 × 1 by the pressure regulators 2261 to 2266.
Adjust to 0 ⁵ Pa. Next, inflow valves 2241-22
46 is gradually opened to introduce each gas into the mass flow controllers 2211 to 2216.

After the preparation for film formation is completed as described above, a deposited film is formed on the conductive support 3112 as follows. When the conductive support (3112) reaches a predetermined temperature, gradually open the necessary one of the outflow valves 2251 to 2256 and the auxiliary valve 2260,
A predetermined gas is introduced from the gas cylinders 2221 to 2226 into the discharge space 3130 in the reaction vessel 3111 via a gas introduction pipe (not shown). Next, mass flow controller 2
The raw material gases are adjusted so as to have a predetermined flow rate by 211 to 2216. At that time, the opening of the main valve (not shown) is adjusted while observing the vacuum gauge (not shown) so that the pressure in the discharge space 3130 becomes a predetermined pressure of 133 Pa or less.

At a stable pressure, 50 MHz to 4 MHz
A VHF power supply (not shown) having a frequency of 50 MHz, for example, a frequency of 105 MHz is set to a desired power, and the VHF power is introduced into the discharge space 3130 through the matching box 3116 to cause glow discharge. Thus the support 311
In the discharge space 3130 surrounded by 2, the introduced source gas is excited by discharge energy and dissociated, and a predetermined deposited film is formed on the support 3112.
At this time, simultaneously with the introduction of VHF power, the output of the heater 3113 for heating the support is adjusted to change the temperature of the conductive support at a predetermined value. At this time, in order to make the layer formation uniform, the support rotating motor 3120 is rotated at a desired rotation speed.

After forming a layer having a desired film thickness, VH
The supply of F electric power is stopped, the outflow valve is closed to stop the gas from flowing into the reaction vessel, and the formation of the deposited film is completed. By repeating the same operation a plurality of times, a desired light receiving member having a multilayer structure is formed.

Needless to say, all the outflow valves other than the necessary gas were closed when forming each layer, and each gas was used in the reaction vessel 3111.
Inside, outflow valves 2251 to 2256 to reaction vessel 311
In order to avoid remaining in the pipe up to 1, the outlet valves 2251 to 2256 are closed, the auxiliary valve 2260 is opened, and the main valve (not shown) is fully opened to temporarily exhaust the system to a high vacuum. Do as needed.

Needless to say, the above-mentioned gas species and valve operation may be changed according to the conditions for forming each layer.

In the image forming method of the present invention, the charging step (primary charging step) of charging the photoconductor uses the so-called contact charging method in which the charging member is brought into contact with the photoconductor for charging as described above. It is preferably a step. By using such a charging method, uniform charging is performed even with a small amount of discharge, and the generation of flow images due to discharge can be reduced, which is preferable.

Further, by inserting fine particles in which the above-mentioned zinc oxide containing a different element is supported on the surface of the base particles, in the contact portion between the charging member and the photosensitive member, the charge is directly injected into the photosensitive member. It is more preferable because the charging by injection causes uniform charging and there is no influence of image deterioration due to discharge.

Further, from the viewpoints of downsizing and cost reduction, the image forming method of the present invention does not provide a cleaner device for removing the toner remaining on the photoconductor after the transfer step, and the residual toner after the transfer is developed after the developing step. It is more preferable that the image forming method is a cleanerless method of collecting with a toner carrier.

As the charging means (contact charging means) for carrying out the contact charging, there are a method using a charging roller and a charging blade, and a method using a conductive brush.

The material of the charging roller and the charging blade as the contact charging means is preferably conductive rubber, and a release coating may be provided on the surface thereof. As the release film, nylon resin, PVdF (polyvinylidene fluoride), PV
dC (polyvinylidene chloride), fluoroacrylic resin, etc. are applicable.

The charging roller (elastic conductive roller) using the above-mentioned conductive rubber as the roller member has poor shape when the hardness is too low, resulting in poor contact with the member to be charged. By interposing the fine particles in the contact portion between the member and the image carrier, the surface layer of the elastic conductive roller is scraped or damaged, and stable charging property cannot be obtained. Further, if the hardness is too high, not only the charging contact portion cannot be secured between the charged body and the micro contact property to the surface of the charged body is deteriorated, but the Asker C hardness is 25 to 50 degrees. preferable.

It is important that the elastic conductive roller has elasticity to obtain a sufficient contact state with the photoconductor and at the same time functions as an electrode having a resistance low enough to charge the moving photoconductor. On the other hand, it is necessary to prevent voltage leakage when there is a defective portion such as a pinhole on the photoconductor. When an electrophotographic photoreceptor is used, in order to obtain sufficient chargeability and leak resistance, the volume resistivity value is 10 ³ to
The resistance value should be in the range of 10 ⁸ Ω · cm, and more preferably 10 ⁴ to 10 ⁷ Ω · cm.

The resistance value of the elastic conductive roller is 100 V between the core metal and the aluminum drum in a state where the roller is pressure-bonded to a cylindrical aluminum drum of φ30 mm so that a total pressure of 1 kg is applied to the core metal of the roller. It is calculated from the resistance value applied, the nip width at the time of measurement, and the thickness of the elastic body.

For example, the elastic conductive roller is manufactured by forming a medium resistance layer of rubber or foam as a flexible member on a core metal. The medium resistance layer is formulated with a resin (for example, urethane), conductive particles (for example, carbon black), a sulfiding agent, a foaming agent, etc., and is formed in a roller shape on the cored bar. After that, if necessary, the surface can be cut and the shape can be adjusted to prepare an elastic conductive roller.

Further, it is preferable that the surface of the elastic conductive roller has minute cells or irregularities for interposing the fine particles. That is, at least the surface of the roller member has an average cell diameter of 5 to 300 μm in terms of sphere.
It is preferable that the porosity of the surface of the roller member is 15 to 90%.

The cell diameter is 5 μm or less, and the porosity is 90.
If it exceeds%, the ability to hold the fine particles on the roller surface decreases, and the amount of the fine particles intervening in the contact portion decreases, which may deteriorate the primary charging property. Further, the frictional force between the photoconductor and the roller becomes large, and abrasion of the photoconductor may increase, which is not preferable. Also, the cell diameter is 300 μm
If the porosity exceeds 15%, the contact uniformity between the charging member and the photoconductor is reduced, the charging uniformity of the primary charging property and the charging potential are reduced, and image defects such as uneven charging on halftone images occur. It may occur, which is not preferable.

The material of the conductive elastic roller is not limited to the elastic foam, and the material of the elastic body is
Ethylene-propylene-diene polyethylene (EPD
M), urethane, butadiene acrylonitrile rubber (N
Examples of the rubber material include BR), silicone rubber, isoprene rubber, etc., in which a conductive material such as carbon black or metal oxide is dispersed for resistance adjustment, and those obtained by foaming these materials. Further, it is also possible to adjust the resistance by using an ion conductive material without dispersing the conductive material or in combination with the conductive material.

The conductive elastic roller is arranged in pressure contact with the photosensitive member as the image bearing member with a predetermined pressing force against the elasticity, and the conductive elastic roller and the image bearing member are charged at a charging portion. Form an abutment. The width of the charging contact portion is not particularly limited, but is preferably 1 mm or more, more preferably 2 mm or more in order to obtain a stable and dense adhesion between the conductive elastic roller and the image carrier.

As the charging brush, which is a brush member having conductivity, as the contact charging member, the one whose resistance is adjusted by dispersing a conductive material in commonly used fibers is used. As the fiber, a generally known fiber can be used, for example nylon, acrylic, rayon,
Examples thereof include polycarbonate and polyester. As the conductive material, generally known conductive materials can be used, and examples thereof include conductive metals such as nickel, iron, aluminum, gold and silver, or iron oxide, zinc oxide, tin oxide, antimony oxide, titanium oxide and the like. Examples of the conductive metal oxides are also conductive powders such as carbon black. If necessary, these conductive materials may be surface-treated for the purpose of making them hydrophobic and adjusting their resistance. At the time of use, it is selected and used in consideration of dispersibility with fibers and productivity.

When a charging brush is used as the contact charging member, there are a fixed type and a rotatable roll type. As the roll-shaped charging brush, for example, a tape in which conductive fibers are piled can be spirally wound around a metal cored bar to form a roll brush. The conductive fiber is
Fiber thickness is 1-20 denier (fiber diameter 10-500μ
m), the fiber length of the brush is 1 to 15 mm, and the brush density is 10,000 to 300,000 per square inch (about 1.5 × 10 ^{7 to} 4.5 × 10 ⁸ per square meter). Is preferably used.

From the viewpoint of the primary charging uniformity, it is preferable to use a charging brush having a higher brush density, and it is also preferable to make one fiber from several to several hundred fine fibers. For example, it is possible to bundle 50 fine fibers of 300 denier, such as 300 denier / 50 filaments, and to implant them as one fiber.

However, in the present invention, since the charging point of the direct injection charging mainly depends on the charging contact portion between the charging member and the image carrier and the interposition density of the conductive fine powder in the vicinity thereof, The range of selection of the charging member is widened, and the brush density may be smaller than that when the charging brush is used alone.

As the material of the charging brush, conductive rayon fibers REC-B and REC- manufactured by Unitika Ltd. are used.
C, REC-M1, REC-M10, and Toray Industries, Inc.
SA-7 made by Nippon Silkworm Co., Ltd., Thunderon made by Japan Silkworm Co., Ltd., Bertron made by Kanebo, Cracabo made by Kuraray Co., Ltd., carbon dispersed in rayon, Mitsubishi Rayon Co., Ltd.
There are manufactured products such as locals, but in terms of environmental stability REC-
B, REC-C, REC-M1 and REC-M10 are particularly preferable.

The intervening amount of fine particles at the contact portion between the photosensitive member and the contact charging member will be described below. If the intervening amount of fine particles in the contact portion between the photoconductor and the contact charging member is too small, the lubrication effect of the particles cannot be sufficiently obtained, and the friction between the image carrier and the contact charging member increases, resulting in contact charging. It becomes difficult to rotationally drive the member on the photoconductor with a speed difference. That is, the driving torque becomes excessively large, and the surface of the contact charging member or the photoconductor is scraped if the driving torque is forcedly rotated. Further, the effect of increasing contact opportunities due to the fine particles may not be obtained, and sufficient charging performance may not be obtained. On the other hand, if the intervening amount is too large, the amount of fine particles coming off from the contact charging member remarkably increases, which adversely affects image formation.

The intervening amount of fine particles is 10 ^{2 to} 5 × 10 ⁵ particles / m
m ² is preferred. When the interposition amount is lower than 10 ² pieces / mm ² ,
The sufficient lubrication effect and the effect of increasing contact opportunities cannot be obtained between the photoconductor and the contact charging member, resulting in deterioration of charging performance.
When the transfer residual toner is large, the charging performance is deteriorated.

Further, when the direct injection charging method is applied as the uniform charging of the latent image carrier in the cleaning simultaneous developing image formation, the charging characteristic is deteriorated due to the adhesion or mixing of the transfer residual toner to the charging member. To prevent the transfer residual toner from adhering to and mixing with the charging member, or to overcome the adverse effect on the charging characteristics due to the adhesion or mixing of the transfer residual toner to the charging member, and to perform good direct injection charging, The amount of fine particles present at the contact portion with the contact charging member is 10 ² particles / mm ² or more, more preferably 10 ³ particles / mm ^2.
That is all.

Further, the upper limit of the coating amount of the fine particles is until the fine particles are uniformly coated on the photoconductor, and the effect is not improved even if the fine particles are coated more than that, and the exposure light source is blocked. It causes harmful effects such as scattering and scattering. The upper limit of the coating density varies depending on the particle size of the fine particles, and therefore cannot be generally stated, but the upper limit is the amount of the fine particles uniformly coated on the photoreceptor in one layer.

The amount of fine particles is 5 × 10.^FivePieces / mm²Beyond
When this happens, the number of particles that fall onto the image carrier increases significantly, and
Regardless of the light transmission of itself, insufficient exposure of the image carrier may occur.
Jijiru 5 x 10^FivePieces / mm²The amount of particles that fall out is also low below
It can be suppressed and the inhibition of exposure can be improved. Amount of fine particles
To 10²~ 5 x 10^FivePieces / mm²Image formation as
The amount of particles dropped on the image carrier was measured.
Ro, 10³-10^FivePieces / mm ²Therefore, there is no harmful effect on image formation.
won. Therefore, the upper limit of the preferable amount of inclusion of fine particles
Is 5 × 10^FivePieces / mm²Is.

Next, a method for measuring the amount of fine particles present at the charging contact portion and the amount of fine particles present on the image bearing member in the electrostatic latent image forming step will be described. Although it is desirable to directly measure the amount of intervening particles between the contact charging member and the contact surface of the photosensitive member, if a speed difference is provided between the surface of the contact charging member forming the contact portion and the surface of the photosensitive member, Since most of the particles existing on the photoreceptor before contacting the contact charging member are stripped off by the contacting charging member while moving in the opposite direction, in the present invention, the surface of the contact charging member immediately before reaching the contact surface portion is The amount of particles was defined as the amount of inclusions. Specifically, the rotation of the photoconductor and the elastic conductive roller is stopped without applying a charging bias, and the surfaces of the photoconductor and the elastic conductive roller are covered with a video microscope (OVM1000 made by OLYMPUS).
N) and Digital Still Recorder (DELTIS SR
-3100). For the elastic conductive roller, contact the slide glass under the same conditions as the contact of the elastic conductive roller with the photoconductor, and use a video microscope from the back surface of the slide glass to contact the contact surface with a 1000 × objective lens at 10 or more locations. I took a picture. In order to separate individual particles from the obtained digital image, binarization processing was performed with a certain threshold value, and the number of areas where particles were present was measured using desired image processing software. In addition, the abundance on the image carrier was also measured by photographing the image carrier with the same video microscope and performing the same processing.

Next, the electrostatic latent image forming step will be described. In the image forming method of the present invention, it is preferable to use an electrostatic latent image forming step of writing image information as an electrostatic latent image on the charged surface of the photoconductor by imagewise exposure. That is, it is preferable that the electrostatic latent image forming means for forming an electrostatic latent image on the charged surface of the image carrier is an image exposing means. The image exposure means for forming the electrostatic latent image is not limited to the laser scanning exposure means for forming a digital latent image, but may be a normal analog image exposure or other light emitting element such as an LED. It does not matter as long as it can form an electrostatic latent image corresponding to image information, such as a combination of a light emitting element such as a fluorescent lamp and a liquid crystal shutter.

Next, the developing process will be described. In the developing step in the image forming method of the present invention, the electrostatic latent image on the photoconductor is developed with the toner described above. First, the toner carrier used for development will be described.

The toner carrier used in the present invention is preferably a conductive cylinder (developing roller) formed of a metal or alloy such as aluminum or stainless steel. The conductive cylinder may be formed of a resin composition having sufficient mechanical strength and conductivity, or a conductive rubber roller may be used. Further, the shape is not limited to the cylindrical shape as described above, and may be in the form of an endless belt that is rotationally driven.

In the present invention, 5 to 5 are formed on the toner carrier.
It is preferable to form a toner layer of 50 g / m ² . If the amount of toner on the toner carrier is less than 5 g / m ² ,
It is difficult to obtain a sufficient image density, and the toner layer becomes uneven due to excessive charging of the toner. When the amount of toner on the toner carrier is more than 50 g / m ² , toner scattering easily occurs.

The surface roughness of the toner carrier used in the present invention is from 0.2 to JIS center line average roughness (Ra).
It is preferably in the range of 3.5 μm. Ra is 0.2
If it is less than μm, the amount of charge on the toner carrier becomes high and the developability becomes insufficient. When Ra exceeds 3.5 μm, unevenness occurs in the toner coat layer on the toner carrier, resulting in uneven density on the image. Ra is more preferably in the range of 0.5 to 3.0 μm.

In the present invention, the surface roughness Ra of the toner carrier is based on JIS surface roughness "JISB 0601" using a surface roughness measuring instrument (Surfcoder SE-30H, Kosaka Laboratory Ltd.). It corresponds to the center line average roughness measured by.

In the present invention, the toner on the toner carrier is regulated by the ferromagnetic metal blade which is arranged facing the toner carrier with a minute interval, so that the powder characteristics and the charging characteristics of the toner can be controlled. It is particularly preferable from the viewpoint of maintaining uniform properties for a long period of time, being hardly affected by the temperature and humidity environment, and obtaining uniform charging in which toner scattering does not easily occur.

Further, in the image forming method of the present invention,
By making the moving speed of the toner carrier that carries the toner in the developing step and conveys it to the developing section to a speed difference with respect to the moving speed of the photoconductor, the toner particles and fine particles are sufficiently transferred from the toner carrier to the photoconductor side. Since it can be supplied, a good image can be obtained.

The surface of the toner carrying member carrying the toner may move in the same direction as the moving direction of the photosensitive member surface,
It may be moving in the opposite direction. When the moving directions are the same, it is desirable that the ratio is 100% or more with respect to the moving speed of the photoconductor. If it is less than 100%, the image quality will deteriorate. As the moving speed ratio increases, the amount of toner supplied to the developing portion increases, the toner desorption frequency increases with respect to the electrostatic latent image, and unnecessary portions are scraped off and applied to necessary portions. By repeating the above, an image faithful to the latent image can be obtained. The speed ratio is a value calculated by the following formula.

[0286]

## EQU6 ## Speed ratio (%) = (toner carrier speed / photoconductor speed) × 100 Specifically, the moving speed of the surface of the toner carrier is 1.05 to 3. It is preferable that the speed is 0 times.

The developing step in the present invention is preferably a non-contact type developing method in which the photosensitive member and the toner carrying member are in non-contact with each other. The contact developing method is not preferable because charges are easily injected into the photoconductor by the fine particles in the developing section, the latent image is disturbed, image defects are likely to occur, and fogging is likely to occur in the developing section.

In the case of the non-contact developing method, it is preferable to form the toner layer on the toner carrier thinner than the distance between the toner carrier and the photoconductor. In the developing process, the toner layer is not in contact with the photoconductor, and a non-contact type developing method is used in which the electrostatic latent image of the photoconductor is visualized as a toner image. Even if added in the inside, the development fog does not occur due to the development bias being injected into the photoreceptor. Therefore, a good image can be obtained.

Further, the toner carrier is 10
It is preferable that they are installed facing each other with a separation distance of 0 to 1000 μm, and it is further preferable that they are installed facing each other with a separation distance of 120 to 500 μm. If the separation distance of the toner carrier from the photoconductor is smaller than 100 μm, the change in the developing characteristics of the toner due to the deviation of the separation distance becomes large, which makes it difficult to mass-produce an image forming apparatus satisfying a stable image property. . When the distance between the toner carrier and the photoconductor is larger than 1000 μm, the collectability of the transfer residual toner to the developing device is deteriorated, and fogging due to defective collection is likely to occur. Further, since the ability of the toner to follow the latent image on the photoconductor is lowered, the resolution is lowered,
This causes deterioration in image quality such as a decrease in image density.

In the present invention, it is preferable that development is carried out in a developing process in which an alternating electric field is applied to the toner carrier to perform development, and the applied developing bias is a DC voltage even if an alternating voltage (AC voltage) is superimposed. Good.

As the waveform of the alternating voltage, a sine wave, a rectangular wave, a triangular wave or the like can be appropriately used. Further, it may be a pulse wave formed by periodically turning on / off the DC power supply. Thus, as the waveform of the alternating voltage, a bias whose voltage value changes periodically can be used.

At least a peak-to-peak electric field strength of 3 × 10 ⁶ to 10 × 10 ⁶ V / m is provided between the toner carrier carrying the toner and the photoconductor, and the frequency of 100 to
It is preferable to apply an alternating electric field of 5000 Hz as a developing bias. When the electric field strength of the developing bias applied between the toner carrier and the photoconductor is smaller than 3 × 10 ⁶ V / m, the collectability of the transfer residual toner to the developing device is deteriorated and the fog caused by the collecting failure occurs. It tends to occur. Further, since the developing power is small, an image having a low image density is likely to be obtained. On the other hand, when the electric field strength of the developing bias is larger than 10 × 10 ⁶ V / m, the developing power is too large and the resolution is deteriorated due to the collapse of fine lines, and the image quality is easily deteriorated due to the increase of fog. Image defects easily occur due to leakage to the body. Further, the frequency of the AC component of the developing bias applied between the toner carrier and the photoconductor is 100H.
If it is smaller than z, the toner is less frequently attached to and detached from the latent image, the collectability of transfer residual toner to the developing device is likely to be deteriorated, and the image quality is also likely to be deteriorated. When the frequency of the AC component of the developing bias is higher than 5000 Hz, the amount of toner that can follow the change in the electric field is reduced, so that the collectability of the transfer residual toner is lowered and the developability is lowered.

Even if there is a high potential difference between the toner carrier and the photoconductor due to application of an alternating electric field as the developing bias, charge is not injected into the photoconductor by the developing unit, and therefore the toner on the side of the toner carrier does not enter the toner. The added fine particles are likely to be uniformly transferred to the photoconductor side, and the fine particles are uniformly applied to the photoconductor, and uniform contact is made at the charging portion, whereby good chargeability can be obtained.

Next, the contact transfer step of the image forming method of the present invention will be specifically described. In the present invention, the recording medium to which the toner image is transferred from the photoconductor may be an intermediate transfer body such as a transfer drum. When the recording medium is an intermediate transfer member, a toner image is obtained by transferring the intermediate transfer member to a transfer material such as paper again.

In the contact transfer step, the developed image is electrostatically transferred onto the transfer material while the transfer means is in contact with the photosensitive member via the transfer material. The contact pressure of the transfer means is a linear pressure of 2. It is preferably 9 N / m (3 g / cm) or more, and more preferably 19.6 N / m (20 g / cm) or more. The linear pressure as a contact pressure is 2.9 N / m (3 g
/ Cm) is not preferable because the transfer material may be misaligned or transfer failure may occur.

As the transfer means in the contact transfer step, a device having a transfer roller or a transfer belt is used. The transfer roller is composed of at least a core metal and a conductive elastic layer, and the conductive elastic layer is made of urethane having a conductive material such as carbon dispersed therein or EPDM and has a volume resistance of 10 ⁶ to 1 1.
It is made of an elastic material of about 0 ¹⁰ Ωcm, and a transfer bias is applied by a transfer bias power source.

[0297]

EXAMPLES The photoconductor and toner, the fine particles contained in the toner, and the charging member used in the image forming method of the present invention will be specifically described below with reference to examples. The present invention is not limited to these examples.

<Photoreceptor Production Examples 1 to 6> RF-shown in FIG.
Using a PCVD apparatus, a charge injection blocking layer and a photoconductive layer were laminated on a cylindrical conductive substrate under the following conditions, and then a surface layer was deposited to a thickness of 0.5 μm under the following conditions (1) to (6). Photosensitive members 1 to 6 were manufactured. Further, as a sample for measuring the silicon atom content and hydrogen content of the surface layer, a surface layer sample was prepared on the glass substrate and the silicon wafer under the following conditions (1) to (6), respectively, and The content was measured. Table 1 shows the contents of silicon atoms and hydrogen atoms in the surface layers of the photoconductors 1 to 6, respectively.

[Production Conditions of Photoreceptor] (Charge injection blocking layer) SiH ₄ 100 ml / min (normal) H ₂ 300 ml / min (normal) PH ₃ 800 ppm (relative to SiH ₄ ) NO 5 ml / min (normal) power 150 W (13.56 MHz) Internal pressure 80 Pa Base temperature 280 ° C. Film thickness 3 μm (photoconductive layer) SiH ₄ 350 ml / min (normal) H ₂ 600 ml / min (normal) B ₂ H ₆ 0.5 ppm (relative to SiH ₄ ) Power 400 W (13.56 MHz) Internal pressure 73 Pa Base temperature 280 ° C. Film thickness 20 μm (1) Surface layer CH ₄ of photoconductor 1 500 ml / min (normal) Power 1000 W (13.56 MHz) Internal pressure 66.7 Pa Substrate temperature 200 ° C. (2 ) surface layer CH ₄ of the photoreceptor 2 500ml / min (normal) power 800W (13.56M z) pressure 13.3Pa substrate temperature 300 ° C. (3) the surface layer CH ₄ 500 ml / min of the photoreceptor 3 (normal) Power 1500 W (13.56 MHz) pressure 13.3Pa substrate temperature 300 ° C. (4) the surface of the photoreceptor 4 Layer CH ₄ / H ₂ 100 ml / min (normal) / 200 mL / min
(Normal) Power 500 W (13.56 MHz) Internal pressure 6.7 Pa Substrate temperature 150 ° C. (5) Surface layer CH ₄ / H _{2 of} photoconductor 5 100 ml / min (normal) / 200 ml / min
(Normal) Power within 500 W (13.56 MHz) 4.0 Pa Substrate temperature Room temperature (6) Surface layer of photoconductor 6 SiH ₄ / CH ₄ / H ₂ 0.4 ml / min (normal) / 100 ml / min
(Normal) / 200 ml / min (normal) power 500 W (13.56 MHz) internal pressure 40.0 Pa substrate temperature 250 ° C.

[0300]

[Table 1] <Charging member manufacturing example 1> SU having a diameter of 6 mm and a length of 320 mm
S roller is used as a core metal, urethane resin, carbon black as conductive particles, sulfidizing agent, foaming agent, etc. are formed on the core metal to form a urethane foam layer of medium resistance in the shape of a roller, which is further cut and ground to form The surface property was adjusted, and a charging roller 1 having a diameter of 12 mm and a length of 320 mm was manufactured as a flexible member. Table 2 shows the physical properties of the charging roller 1.

<Production Example 2 of Charging Member> In Production Example 1 of the charging member, the amount of carbon black added was 10 as in Production Example 1 above.
A charging roller 2 was produced in the same manner as in Manufacturing Example 1 except that the charging roller 2 was doubled. Table 2 shows the physical properties of the charging roller 2.

<Charging Member Manufacturing Example 3> A charging roller 3 was manufactured in the same manner as in Manufacturing Example 1 except that carbon black was not added in Charging Member Manufacturing Example 1. Table 2 shows the physical properties of the charging roller 3.

<Charging Member Production Example 4> A roll-type charging brush 4 was prepared by using a SUS roller of φ6, 320 mm as a core metal, and spirally winding a tape having conductive nylon fibers as a pile on the core metal. The thickness of the conductive nylon fiber whose resistance is adjusted by dispersing carbon black in the nylon fiber is 6 denier (300 denier / 50 filament), the fiber length is 3 mm, and the brush density is 1 cm ^2.
The number of flocked hairs per 15,500 was used.

<Charging Member Production Example 5> Silicone rubber 100 parts by mass Paraffin oil 10 parts by mass Zinc oxide 6 parts by mass Higher fatty acid 1 part by mass Conductive carbon black 5 parts by mass The above mixer was adjusted to 50 ° C. in a closed mixer. 10
A raw material compound is prepared by kneading for 1 minute, and 2 parts by mass of sulfur as a vulcanizing agent and MB as a vulcanization accelerator are added to 100 parts by mass of raw material silicone rubber.
1 part by mass of T (2-mercaptobenzothiazole) and 1 part of TMTD (tetramethylthiuram disulfide).
5 parts by mass and 1.5 parts by mass of ZnMDC (zinc dimethyldithiocarbamate) were added, and the mixture was kneaded for 10 minutes with a two-roll machine cooled to 20 ° C. to prepare a rubber compound.

A stainless steel core having an outer diameter of 9 mm was prepared, and the rubber compound was extruded on the core so as to form a roller having an outer diameter of 16 mm by an extrusion molding machine. It was heat-vulcanized for a minute. From this, an elastic roller having a resistance value of 4 × 10 ³ Ωcm was produced.

As the surface coating layer, 5 parts by mass of zinc oxide was added to 100 parts by mass of N-methoxymethylated nylon (trade name: Toresin, manufactured by Teikoku Kagaku Sangyo Co., Ltd.), and the mixture was placed on a ball mill for 4 hours. The dispersed resin solution was prepared. This resin solution is applied to an elastic roller by dipping to form a surface layer, which is heated and dried at 120 ° C. for about 1 hour, and the charging member 5 having a surface layer with a thickness of 20 μm.
Got

Table 2 shows the physical properties of the above charging members.

[0308]

[Table 2] <Fine Particle Production Example 1> 100 parts by mass of zinc oxide is dispersed in water, 15 parts by mass of aluminum sulfate and 15 parts by mass of aqueous solution of ammonium carbonate are added to the zinc oxide dispersion liquid, and the mixture is sufficiently stirred to obtain a uniform mixture. A slurry was prepared. Spherical silica (300 parts by mass) was added to this slurry,
Heating was carried out at 0 ° C for 1 hour. After washing the slurry with filtered water,
After being dried, it was fired for 1 hour in a reduction firing furnace (850 ° C.) in a hydrogen atmosphere. The obtained fired body was crushed and then classified to obtain fine particles 1.

<Fine Particle Production Example 2> Water was added to 100 parts by mass of zinc oxide and the mixture was sufficiently stirred, and then titanium oxide particles (400
(Parts by mass), KOH was further added, and the mixture was heated at 70 ° C. for 30 minutes. An aqueous KOH solution having 10 parts by mass of aluminum chloride dissolved therein was added thereto, and the mixture was heated at 70 ° C. for 1 hour.
After heating, the product is filtered, washed with water and thoroughly dried,
Firing was performed for 1 hour in a reduction firing furnace (650 ° C.) in a hydrogen atmosphere. Fine particles 2 obtained by crushing the obtained fired body and then classifying
Got

<Fine Particle Production Example 3> Zn / Al = 1/0.
The spherical silica was impregnated with an aqueous solution of zinc sulfate and aluminum sulfate mixed at a ratio of 15 (molar ratio), and dried at 120 ° C. Disperse this in sodium hydroxide solution,
Heated at ° C for 1 hour. After that, the product is filtered, washed with water, dried, and then dried in a hydrogen atmosphere reducing firing furnace (600 ° C.) for 1 hour.
Burned for hours. The fired body was crushed and then classified to obtain fine particles 3.

<Fine Particle Production Example 4> A fine particle 4 having a volume average particle diameter of 0.03 μm was prepared in the same manner as in the above Production Example 1 except that the classification of the fired body was adjusted.
Got

<Fine Particle Production Example 5> Fine particle 5 was obtained in the same manner as in Production Example 2 except that the particle diameter of the spherical silica and the classification of the calcined product were adjusted.

<Fine Particle Production Example 6> 50 parts by mass of zinc oxide is dispersed in water, and 5 parts by mass of aluminum sulfate and 15 parts by mass of ammonium carbonate are added to the zinc oxide dispersion liquid and sufficiently stirred. , A uniform slurry was prepared. Spherical silica (300 parts by mass) was added to this slurry and heated at 60 ° C. for 1 hour. The slurry is filtered, washed with water, dried, and then subjected to a reduction firing furnace (8
It was baked at 50 ° C. for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 6.

<Fine Particle Production Example 7> 200 parts by mass of zinc oxide was dispersed in water, and 25 parts by mass of aluminum sulfate and 15 parts by weight were added.
An aqueous solution of each part by mass of ammonium carbonate was added to the zinc oxide dispersion liquid and sufficiently stirred to prepare a uniform slurry. Spherical silica (300 parts by mass) in this slurry
Was added and the mixture was heated at 60 ° C. for 1 hour. The slurry was filtered, washed with water, dried, and then calcined in a hydrogen atmosphere reducing calcination furnace (850 ° C.) for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 7.

<Fine Particle Production Example 8> A volume average particle diameter of 1.1 μm was obtained by the same method as in the above Production Example 2 except that the aluminum compound was not added in Production Example 2 of fine particles.
m fine particles 8 were obtained.

<Fine Particle Production Example 9> Water was added to 100 parts by mass of zinc oxide and sufficiently stirred, then 60 parts by mass of titanium oxide particles were added, KOH was further added, and the mixture was heated at 70 ° C. for 30 minutes. An aqueous KOH solution having 10 parts by mass of aluminum chloride dissolved therein was added thereto, and the mixture was heated at 70 ° C. for 1 hour. After heating, the slurry was filtered, washed with water, sufficiently dried, and then calcined in a hydrogen atmosphere reducing calciner (650 ° C.) for 1 hour.
The obtained fired body was crushed and then classified to obtain fine particles 9.

<Fine Particle Production Example 10> After adding water to 100 parts by mass of zinc oxide and stirring the mixture sufficiently, 32 parts by mass of titanium oxide particles were added, KOH was further added, and the mixture was heated at 70 ° C. for 30 minutes. An aqueous KOH solution having 10 parts by mass of aluminum chloride dissolved therein was added thereto, and the mixture was heated at 70 ° C. for 1 hour. After heating, the slurry was filtered, washed with water, sufficiently dried, and then calcined in a hydrogen atmosphere reducing calciner (650 ° C.) for 1 hour.
The obtained fired body is crushed and then classified to obtain fine particles 10
Got

<Fine Particle Production Example 11> 100 parts by mass of zinc oxide was dispersed in water, and 15 parts by mass of aluminum sulfate and 1 were mixed.
5 parts by mass of each aqueous solution of ammonium carbonate was added to the above zinc oxide dispersion and sufficiently stirred to prepare a uniform slurry. Spherical silica (6000 parts by mass) was added to this slurry and heated at 60 ° C. for 1 hour. The slurry was filtered, washed with water, dried, and then calcined in a hydrogen atmosphere reducing calcination furnace (850 ° C.) for 1 hour. The fired body obtained was crushed and then classified to obtain fine particles 11.

<Fine Particle Production Example 12> 100 parts by mass of zinc oxide was dispersed in water to prepare 15 parts by mass of aluminum sulfate and 1 part by weight.
5 parts by mass of each aqueous solution of ammonium carbonate was added to the above zinc oxide dispersion and sufficiently stirred to prepare a uniform slurry. Spherical silica (3600 parts by mass) was added to this slurry and heated at 60 ° C. for 1 hour. The slurry was filtered, washed with water, dried, and then calcined in a hydrogen atmosphere reducing calcination furnace (850 ° C.) for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 12.

<Fine Particle Production Example 13> 100 parts by mass of zinc oxide was dispersed in water, and 0.15 parts by mass of aluminum sulfate and 15 parts by mass of ammonium carbonate were added to the zinc oxide dispersion liquid, and the mixture was thoroughly mixed. Stirring was performed to prepare a uniform slurry. Spherical silica (30
(0 part by mass) was added, and the mixture was heated at 60 ° C. for 1 hour. The slurry was filtered, washed with water, dried, and then calcined in a hydrogen atmosphere reducing calcination furnace (850 ° C.) for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 13.

<Fine Particle Production Example 14> 100 parts by mass of zinc oxide is dispersed in water, and 0.3 parts by mass of aluminum sulfate and 15 parts by mass of ammonium carbonate are added to the zinc oxide dispersion liquid, and the mixture is thoroughly mixed. Stirring was performed to prepare a uniform slurry. Spherical silica (300
(Parts by mass) was added and the mixture was heated at 60 ° C. for 1 hour. The slurry was filtered, washed with water, dried, and then calcined in a hydrogen atmosphere reducing calcination furnace (850 ° C.) for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 14.

<Fine Particle Production Example 15> Water was added to 100 parts by mass of zinc oxide and the mixture was thoroughly stirred, and then titanium oxide particles 40 were added.
0 parts by mass was added, KOH was further added, and the mixture was heated at 70 ° C. for 30 minutes. An aqueous KOH solution having 50 parts by mass of aluminum chloride dissolved therein was added thereto, and the mixture was heated at 70 ° C. for 1 hour.
After heating, the slurry was filtered, washed with water, sufficiently dried, and then calcined in a reducing calcination furnace (650 ° C.) in a hydrogen atmosphere for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 15.

<Fine Particle Production Example 16> Water was added to 100 parts by mass of zinc oxide and sufficiently stirred, and then titanium oxide particles 40 were added.
0 parts by mass was added, KOH was further added, and the mixture was heated at 70 ° C. for 30 minutes. An aqueous KOH solution having 40 parts by mass of aluminum chloride dissolved therein was added thereto, and the mixture was heated at 70 ° C. for 1 hour.
After heating, the slurry was filtered, washed with water, sufficiently dried, and then calcined in a reducing calcination furnace (650 ° C.) in a hydrogen atmosphere for 1 hour. The obtained fired body was crushed and then classified to obtain fine particles 16.

The above fine particles 1 to 7 and 9 to 16 were dipped in an aqueous hydrochloric acid solution for treatment, and the treatment time was changed by changing the soaking time, and the zinc oxide particles dipped in the aqueous hydrochloric acid solution were separated from the aqueous hydrochloric acid solution. I took it out. The particles were surface analyzed by ESCA. As a result, it was confirmed that the atomic percentages of the zinc element and the aluminum element decreased in almost the same proportions as the treatment time increased in all the fine particles, and both the elements were mainly present on the surface of the base particle. I found out.

The content (mol%) of zinc element and elements other than zinc element in the fine particles was analyzed by an inductively coupled plasma emission spectroscopic analyzer (ICP-AES). Also,
As for the content of elements other than zinc element (aluminum in the above-mentioned production examples) to zinc, the content of zinc element and aluminum is determined by inductively coupled plasma optical emission spectrometry (IC).
P-AES), and converted to mol to calculate mol%.

The content of zinc element in the whole fine particles was determined by the following method. That is, in each of the above production examples, the content of zinc, aluminum, silicon, or titanium is determined by an inductively coupled plasma emission spectroscopic analyzer (ICP).
-AES), and the other composition was assumed to be oxygen (each element exists in the state of oxide). Converting all these elements to mol, the total mol
The mol number of zinc with respect to the number was expressed by mol% and calculated.

Table 3 shows the content of zinc element in each fine particle (m
ol%), content (mol%) of elements other than zinc excluding the base particles with respect to zinc element, volume average particle size, and 2
It shows the resistance under the environment of 3 ° C./60% relative humidity and 23 ° C./5%.

[0328]

[Table 3] From Table 3, it was found that the fine particles containing aluminum as a different element in zinc oxide had less resistance variation due to the environment than the fine particles containing no different element.

<Toner Particle Production Example 1> Ion-exchanged water 70
It was charged 0.1M-Na ₃ PO ₄ aqueous solution 451g to 9 g 6
After warming to 0 ° C., a 1.0 M CaCl ₂ aqueous solution 67.
7 g was gradually added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

Styrene 80 parts n-Butyl acrylate 20 parts Unsaturated polyester resin 2 parts Saturated polyester resin 3 parts Negative charge control agent (monoazo dye-based Fe compound) 1.2 parts Surface-treated hydrophobized magnetic material 95 parts The above formulation Was uniformly dispersed and mixed using an attritor (Mitsui Miike Kakoki Co., Ltd.). This monomer composition was heated to 60 ° C., and an ester wax containing behenyl behenate as a main component (maximum value of endothermic peak in DSC 72
℃) 6 parts was added and mixed and dissolved, and the polymerization initiator 2, 2 '
5 g of -azobis (2,4-dimethylvaleronitrile) [half-life t _1/2 = 140 minutes, at 60 ° C.] was dissolved.

The above polymerizable monomer system is added to the above aqueous medium.
Enter, 60 ℃, N₂TK homomixer under atmosphere
-(Special Kika Kogyo Co., Ltd.) 1 at 10,000 rpm
The mixture was stirred for 5 minutes and granulated. After that, stir with a paddle stirring blade
While reacting at 60 ° C. for 6 hours. After that, adjust the liquid temperature to 80 ° C.
The stirring was continued for another 4 hours. After the reaction is completed, the temperature is changed to 80 ℃.
Distill for 2 hours, then cool the suspension and add hydrochloric acid.
In addition Ca₃(PO_Four) ₂Dissolved, filtered, washed with water, dried
As a result, toner particles 1 having a mass average particle diameter of 6.8 μm were obtained.

<Toner Particle Production Example 2> The toner particles 1 obtained in Toner Particle Production Example 1 are used in a biaxial extruder to obtain 130
Melt kneading was performed at ℃. The melt-kneaded product was crushed with a hammer mill to obtain a 1-mm mesh-pass toner crushed product. Further, this coarsely pulverized product was finely pulverized by a collision type pulverizer using a jet stream, and then classified by wind force, and the volume average particle size was 7.
Toner particles 2 of 4 μm were obtained.

<Toner Particle Production Example 3> Polyester resin (Tg 60 ° C., molecular weight: peak molecular weight (Mp) 690
0, Mn3050, Mw54500) 100 parts by mass, monoazo metal complex (negative charge control agent) 3.0 parts by mass, low molecular weight ethylene-propylene copolymer (endothermic main peak temperature: 86 ° C, exothermic main peak temperature: 86.5). ° C) 3.
After mixing 5 parts by mass with a Henschel mixer, the temperature was adjusted to 13
Kneading was performed by a twin-screw kneader set to 0 ° C. The kneaded product was cooled, roughly crushed with a hammer mill, and then crushed with a mechanical crusher (turbo mill). Further, classification was performed with an airflow classifier to obtain non-magnetic toner particles 3 having a mass average particle diameter of 7.5 μm.

<Toner Particle Production Example 4> Toner particles 1 obtained in Production Example 1 were added with 10 parts by weight of the fine particles 1 obtained in Production Example 1 of fine particles, and the mixture was mixed with a twin-screw extruder to obtain 130 parts.
Melt kneading was performed at ℃. The melt-kneaded product was crushed with a hammer mill to obtain a 1-mm mesh-pass toner crushed product. Further, this coarsely pulverized product was finely pulverized by a collision type pulverizer using a jet stream, and then classified by wind force, and the volume average particle size was 7.
8 μm toner particles 4 were obtained.

<Toner Production Example 1> 100 Toner Particles 1
1.5 parts by weight of the fine particles 1 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil are added to the parts by weight, and a Henschel mixer (Mitsui Miike Kako Co., Ltd.) is added.
And mixed to obtain Toner 1.

<Toner Production Example 2> 100 Toner Particles 1
1.2 parts by weight of fine particles 2 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to parts by weight, and a Henschel mixer (Mitsui Miike Kako Co., Ltd.) was added.
And mixed to obtain Toner 2.

<Toner Production Example 3> 100 Toner Particles 1
1 part by weight of the fine particles 3 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to the parts by weight and mixed by a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to obtain Toner 3. .

<Toner Production Example 4> 100 Toner Particles 1
0.8 parts by weight of fine particles 4 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil are added to the parts by weight, and a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) is added.
And mixed to obtain Toner 4.

<Toner Production Example 5> 100 toner particles 1
5 parts by weight of fine particles 5 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to the parts by weight, and mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to obtain toner 5. .

<Toner Production Example 6> 100 toner particles 1
2 parts by weight of fine particles 6 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to 1 part by weight, and mixed with a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to obtain toner 6. .

<Toner Production Example 7> 100 toner particles 1
3 parts by weight of fine particles 7 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to 1 part by weight, and mixed with a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to obtain toner 7. .

<Toner Production Example 8> 100 toner particles 1
1.5 parts by weight of the fine particles 8 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to the parts by weight, and a Henschel mixer (Mitsui Miike Kako Co., Ltd.) was added.
And mixed to obtain Toner 8.

<Toner Production Example 9> In Toner Production Example 1, the addition amount of the fine particles 1 is set to 3 parts by mass, and the mixing time by the Henschel mixer is 1 / time of the time for producing the toner 1.
Toner 9 was obtained in the same manner as in Toner Production Example 1 except that the amount was changed to 20.

<Toner Manufacturing Example 10>
To 0 part by mass, 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil was added and mixed by a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to obtain toner 10.

<Toner Production Example 11> 10 toner particles
11 parts by weight of the fine particles 1 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to 0 parts by weight, and a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) was added.
And mixed to obtain Toner 11.

<Toner Production Example 12> 10 toner particles
To 0 parts by mass, 0.12 parts by mass of the fine particles 1 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to prepare toner 12 Got

<Toner Production Example 13> 10 Toner Particles 2
To 0 parts by mass, 2 parts by mass of fine particles 1 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added and mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to obtain toner 13. It was

<Toner Production Example 14> 10 toner particles
To 0 parts by mass, 2.8 parts by mass of the fine particles 1 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to prepare toner 14 Got

<Toner Production Example 15> 10 toner particles
1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil was added to 0 parts by mass and mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to obtain toner 15.

<Toner Production Example 16> 10 toner particles
To 0 part by mass, 1.5 parts by mass of fine particles 9 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed with a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to prepare toner 16 Got

<Toner Production Example 17>
To 0 part by mass, 1.5 parts by mass of the fine particles 10 and 1 part by mass of the hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed with a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to prepare toner 17 Got

<Toner Production Example 18> 10 toner particles 1
To 0 part by mass, 1.5 parts by mass of fine particles 11 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed by a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to prepare toner 18 Got

<Toner Production Example 19> 10 toner particles
To 0 part by mass, 1.5 parts by mass of the fine particles 12 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed by a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to prepare toner 19 Got

<Toner Production Example 20> 10 Toner Particles 1
1 part by weight of fine particles 13 and 1 part by weight of hydrophobic silica fine powder treated with dimethyl silicone oil were added to 0 parts by weight, and a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) was added.
And mixed to obtain Toner 20.

<Toner Production Example 21> 10 toner particles 1
1 part by mass of fine particles 14 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added to 0 parts by mass, and a Henschel mixer (Mitsui Miike Kako Co., Ltd.) was added.
And mixed to obtain Toner 21.

<Toner Production Example 22> 10 toner particles 1
To 0 part by mass, 1.5 parts by mass of the fine particles 15 and 1 part by mass of the hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed by a Henschel mixer (Mitsui Miike Kako Co., Ltd.) to prepare a toner 22. Got

<Toner Production Example 23> 10 Toner Particles 1
To 0 part by mass, 1.5 parts by mass of the fine particles 16 and 1 part by mass of hydrophobic silica fine powder treated with dimethyl silicone oil were added, and mixed by a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to prepare toner 23. Got

Table 4 shows the volume average particle size of the fine particles contained in each of the toners 1 to 23 in the toner state, the release rate, the amount present per toner, the circularity of the toner, and the value of the magnetization strength. Are shown respectively.

The value of the volume average particle diameter of the toner is
Since it was almost the same as the value of the mass average particle diameter, it may be considered that the value of the volume average particle diameter is the same as the value of the mass average particle diameter.

[0360]

[Table 4] The evaluation of the image forming method of the present invention will be described below.

First, an image forming method in which a cleaning device using a cleaning blade is arranged will be described. An organic photoconductor digital copying machine (made by Canon Inc .: GP40) using a laser beam as the image forming apparatus of the present invention.
5) was prepared. The outline of this device is as follows.
A charging roller is provided as a charging unit for the photoconductor, and a one-component developing device in which the toner on the toner carrier and the photoconductor are in non-contact with the one-component jumping developing method is provided as the developing unit. Further, a blade cleaning means and a pre-charging exposure means are provided. Also,
The charging roller, the cleaning means, and the photoconductor are integrated units. Process speed is 210mm
/ S. This device was modified as follows and evaluated according to the following evaluation items.

First, the charging means was changed to the charging member 5 manufactured in the above charging member manufacturing example 5, the central wavelength of laser and pre-exposure was changed to 660 nm, and the photosensitive member was prepared by the photosensitive member manufacturing example 1 described above. An image forming apparatus having a body 1 was prepared.

The charging voltage applied to the charging member is -500V.
A sine wave of 2 kHz and 2.2 kVpp was superposed on the DC voltage of, and this charging voltage was applied from an external power source so as to be applied in synchronization with the timing of rotation of the photoconductor. The transfer voltage is + when the image is formed by transferring the image from the photoconductor.
The constant current control was performed by controlling the voltage to be 20 μA. The developing voltage was controlled such that a rectangular wave of 800 Vpp / 1.8 kHz was superimposed on a -260 V DC component during image formation, and only a -260 V DC voltage was applied during non-image formation.

Evaluation environment 23 using the above image forming apparatus
An endurance evaluation test of 150,000 sheets of A4 horizontal paper having an image ratio of 8% was carried out at a temperature of 5 ° C./relative humidity of 5%, and evaluation was performed according to the following evaluation method.

(Evaluation 1) Evaluation of Image Defects Due to Cleaning Failures Images under the durability evaluation test were observed and evaluated according to the following evaluation items.

⊚: No vertical streak-like defective image due to cleaning failure occurred during the durability evaluation test of 150,000 sheets. ○: Vertical streak-like defective image was slightly generated (100 sheets) during the durability evaluation test of 100,000 sheets or more. (1 or 2 sheets when passing paper) occurred, but it is minor and practically no problem.

Δ: Vertical streak-shaped defective image was generated during the durability evaluation test (1
(5 sheets after passing 00 sheets), and a practical lower limit level x: Vertical streak-shaped defective image due to cleaning failure from the initial stage of the durability evaluation test (Evaluation 2) Fog image, image density evaluation After passing 1000 sheets, A3 A solid white image is printed on a paper of a size, and the fog of the solid white part is reflected by a reflection densitometer (TOKY
O DENSHOKU, REFLECTOME
TER MODEL TC-6DS),
(Dw-D) where the average white background reflection density after image output is solid white Dw and the average reflection density of the paper before image output is Dr.
The evaluation was performed according to the following evaluation items with r) as the fog amount.

A: Fogging is less than 1.5% O: Fogging is 1.5% or more and less than 3% B: Fogging is 3% or more and less than 5% X: Fogging is 5% or more (3) Cleaning during the durability evaluation test Evaluation of the effect on the primary chargeability (charge potential, charge uniformity) of contaminants that slipped from the blade Replace the developing device at the beginning of the durability evaluation test and after passing 150,000 sheets, and replace it with the developing device at the beginning of the durability evaluation test to replace A3 size paper. Then, 20 cm from the front of the image is solid black, and after that, a solid white image is displayed, and the fogging of the solid white part immediately after the solid black is reflected by a reflection densitometer (TOKYODENSHOKU, REFLE
CTOMETER MODEL TC-6DS), and the average value of the reflection density of the white background after printing 150,000 sheets is Dw, the initial durability evaluation test is Ds, and the average value of the reflection density of the paper before the image is Dr. When (Ds-Dr) and (Dw
-Dr) is the fog amount, and the difference in the fog amount ((Dw-
Dr)-(Ds-Dr)) was evaluated according to the following evaluation items, and the primary charging property was evaluated.

The image formation of a solid black-solid white image is a process of causing the charging member to make a rapid rise from the light potential of the photoconductor, and therefore the difference in primary charging ability is remarkable. When the charging ability and the uniformity of charging are lowered, the primary potential is lowered and the background fog is apt to occur. Therefore, the charging property was evaluated by the above evaluation.

⊚: Difference in fog is less than 1.5% ○: Difference in fog is 1.5% or more and less than 3% Δ: Difference in fog is 3% or more and less than 5% ×: Difference in fog is 5% or more ( Evaluation 4) Evaluation of photoconductor wear After the above 150,000 sheets have been passed, the degree of interference of the surface layer of the photoconductor before and after passing the paper is measured by a reflection spectroscopic interferometer (MCPD manufactured by Otsuka Electronics Co., Ltd.).
2000), and the film thickness was calculated from the obtained value of the degree of interference and the known refractive index, and the evaluation was performed according to the following evaluation items.

⊚: The wear amount was not detected within the measurement error and was very good. ◯: It was worn but it was slight, and no image defect due to abrasion was observed in the image. Δ: It was slightly worn and the primary potential A slight decrease in fog was observed in the image Δ ×: A large amount of wear was observed, a decrease in primary potential was observed, and a slight fog occurred in the image. In Table 5, the photoconductor used in this example, The evaluation results of the toner, the charging member, and each evaluation are shown.

Examples 2 to 18 The same evaluations as in Example 1 were carried out except that the photosensitive member and the toner in Example 1 were changed as shown in Table 5. The evaluation results are shown in Table 5.

Comparative Examples 1 to 7 The same evaluations as in Example 1 were carried out except that the photosensitive member and the toner in Example 1 were changed as shown in Table 5. The evaluation results are shown in Table 5.

[0374]

[Table 5] <Embodiment 19> Next, evaluation of an image forming method using a cleanerless system will be described. Similar to Example 1,
An organic photoconductor digital copying machine (GP405, manufactured by Canon Inc.) using a laser beam was prepared. This copying machine was modified as follows to obtain an image forming apparatus as shown in FIG.

First, in the charging portion, the charging member manufacturing example 1 is prepared.
On the surface of the charging member 1 (306 in FIG. 5) manufactured in 1., the fine particles 1 used for manufacturing the toner 1 which is the toner to be evaluated
Was applied so as to be even at 10 ⁴ / mm ² , and then it was mounted. In order to rotate the charging member 1, a rotation motor is modified from the outside so as to be attached to a core metal portion of the charging member, and the rotation of the charging member is controlled so as to be synchronized with the rotation of the photoconductor of the image forming apparatus. The charging member was rotated so as to move in the direction (A direction) opposite to the moving direction (A direction) of the surface of the photosensitive member at the portion in contact with the photosensitive member, and the peripheral speed ratio at this time was controlled to 150%.

Further, the central wavelengths of laser (L) and pre-exposure (P) were changed to 660 nm, the photoconductor 1 (1 in FIG. 5) produced in the photoconductor manufacturing example 1 was mounted, and the cleaning blade was removed. The image forming apparatus of the cleanerless system was prepared. The image forming apparatus of the cleanerless system includes a transfer unit 302 that transfers the toner image developed on the photoconductor 2 to the transfer material 301, and a fixing unit 313 that fixes the transferred toner image on the transfer material 301. ,
Further prepared.

The charging voltage applied to the charging member is -500V.
And The transfer voltage was set to a constant current control in which the voltage was controlled so as to be +15 μA when the image was formed by transferring the image from the photoconductor. The developing voltage is 1000 for the DC component of -260V.
A rectangular wave of Vpp / 1.8 kHz was superimposed.

Durability evaluation was carried out using the above-mentioned image forming apparatus, and evaluation was carried out according to the following evaluation methods.

(Evaluation 1) Evaluation of charge potential of photoconductor Under an environment of 23 ° C./5% relative humidity, an endurance evaluation test was conducted on an image ratio of 8% and 150,000 sheets of A4 horizontal paper. The dark potential was measured at the developing portion at the center position in the longitudinal direction of the photoconductor (Model 344 surface potential meter Trek),
The evaluation was performed according to the following evaluation items.

[0380] ⊚: Charge potential is −350 V or higher ◯: Charge potential is -300 V or more and less than -350 V Δ: Charge potential is −250 V or more and less than −300 V Δx: Charge potential is −200 V or more and less than −250 V X: Charge potential less than -200V

(Evaluation 2) Evaluation of transferability Under an environment of 23 ° C./5%, image ratio 8%, A4 horizontal paper 15
After passing the endurance evaluation test of 10,000 sheets, the photosensitive member and the charging member are stopped during the passing of the transfer process portion of the paper during solid black image formation, and the transfer-charging portion and the development-transfer portion of the photosensitive member are stopped. Was taped with Mylar tape and attached to a stripping evaluation paper. Also, only Mylar tape was attached to the same evaluation paper. The reflection density of each evaluation paper was measured using a Macbeth reflection densitometer. The average value of the reflection densities of the transfer-charging portion is Dtr, and the reflection density of the developing-transfer portion is Dd.
ev, the reflection density of only the tape was set as Dtp, the transfer efficiency was obtained by substituting it in the following formula, and evaluation was performed according to the following evaluation items.

[0382]

[Equation 7] Transfer efficiency (%) = ((Ddev-Dtp)-(Dtr-Dtp))
/ (Ddev-Dtp) × 100 ◎: Transfer efficiency is 90% or more ○: Transfer efficiency is 85% or more and less than 90% △ ×: Transfer efficiency is 80% or more and less than 85% (Evaluation 3) Fog image, image density evaluation 23 100% A4 paper with an image ratio of 8% under a temperature of / 5%
After passing 0 sheets, a solid white image is printed on A3 size paper, and the fogging of the solid white area is reflected by a reflection densitometer (TOKYO D
Made by ENSHOKU, REFLECTOMETER
MODELTC-6DS). (Dw-Dr), where the average white background reflection density after image output is solid white Dw and the average reflection density of the paper before image output is Dr, is the fog amount, and the evaluation is made according to the following evaluation items. went.

A: Fogging is less than 1.5% O: Fogging is 1.5% or more and less than 3% B: Fogging is 3% or more and less than 5% X: Fogging is 5% or more (Evaluation 4) Leak resistance of the charging member In a 32 ° C./85% environment, the photosensitive layer at the initial stage of the evaluation test was peeled off to a substrate with a portion of about 0.2 mm ² in size to form a solid white image, and evaluation was performed according to the following evaluation items. went.

⊚: Image defect remains in the defective portion of the photoconductor ○: Image defect remains in the width of 5 mm around the defective portion of the photoconductor Δ: Image defect mainly in the defective portion of photoconductor The width is limited to 1 cm. ×: Image defects are spread over the entire image (Evaluation 5) Abrasion evaluation of the photoconductor 150,000 sheets of paper are passed under the environment of A4 image ratio 8%, 23 ° C / 5%. The degree of interference of the surface layer before and after passing the paper was measured by a reflection spectroscopic interferometer (MCPD2000 manufactured by Otsuka Electronics Co., Ltd.), and the film thickness was calculated from the obtained value of the degree of interference and the known refractive index. The evaluation was performed according to the evaluation items of.

⊚: The wear amount was not detected within the measurement error and was very good. ◯: It was worn, but it was slight and no image defect was caused by wear. Δ: It was slightly worn and the primary potential decreased. The image was slightly fogged. ΔX: The amount of wear was large, the primary potential was lowered, and the image was slightly fogged.

(Evaluation 6) Toner scattering evaluation by endurance evaluation test 10,000 sheets of paper were passed under the environment of A4 image ratio of 20% and 32 ° C./80%, and the developing device was observed after passing the paper. An evaluation was made.

◯: Good without being scattered on the developing blade, etc. Δ: Degree of slight scattering on the developing blade. Table 6 shows the photoconductor, the toner, the charging member, and the evaluation results of each evaluation used in this example. Indicates.

<Examples 20 to 40> The same evaluations as in Example 19 were carried out except that the photosensitive member and the toner in Example 19 were changed as shown in Table 6. In each of the examples, when the toner to be evaluated was a toner without addition of fine particles, the fine particles 1 were applied to the surface of the charging member. The evaluation results are shown in Table 6.

<Comparative Examples 8 to 14> In Example 19,
Other than changing the photoconductor and toner as shown in Table 6,
The same evaluation as in Example 19 was performed. In each comparative example, when the toner to be evaluated was a toner without addition of fine particles, the fine particles 1 were applied to the surface of the charging member. The evaluation results are shown in Table 6.

[0390]

[Table 6]

[0391]

According to the present invention, in a method of forming an image using a photoconductor having a photoconductive layer composed of a non-single crystal material having silicon atoms as a matrix, at least a binder resin, a colorant, and Zinc oxide is 0.5 to 30 in terms of zinc element
By using a toner containing a fine particle containing 0.1 to 30 mol% of a metal element other than the zinc element in the zinc oxide in a mol% content, even if durable use is performed for a long period of time. It is possible to obtain a uniform charging potential without lowering the primary charging property, and to obtain a clear image for a long period of time without leakage of charging voltage or defective cleaning.

Further, even in the cleanerless system in which the image forming method of the present invention is applied to the simultaneous cleaning image forming method for development, a uniform primary charging potential can be obtained, and a clear image can be obtained for a long time.

[Brief description of drawings]

FIG. 1 is a schematic view of an apparatus for measuring the volume resistance value of fine particles.

FIG. 2 is a schematic cross-sectional view showing an example of a light receiving member.

FIG. 3 is a schematic configuration diagram showing an example of a deposition apparatus used for manufacturing a light receiving member by an RF-PCVD method.

FIG. 4 is a schematic configuration diagram showing an example of a deposition apparatus used for manufacturing a light receiving member by a VHF-PCVD method.

FIG. 5 is a schematic diagram of a cleanerless image forming apparatus according to the present invention.

[Explanation of symbols]

1 photoconductor 11a: Development blade 12 Toner carrier 13 toner 14 magnets 101 conductive substrate 102 charge injection blocking layer 103 Photoconductive layer 104 surface layer 105 charge generation layer 106 charge transport layer 2100, 3100 deposition equipment 2200, 3200 gas supply device 301 Transfer material 302 transfer roller 306 charging member 307 Developing device 313 Fixer P pre-exposure L image exposure

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/02 101 G03G 9/08 301 15/08 507 15/08 507B (72) Inventor Tsuyoshi Takiguchi Tokyo 3-30-2 Shimomaruko, Ota-ku Canon Inc. (72) Inventor Masanori Ito 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F-term (reference) 2H005 AA02 AA08 AA15 CB03 CB07 DA07 EA01 EA05 EA07 EA10 2H068 CA03 DA12 DA14 DA23 2H077 AA37 AD02 AD06 AD13 AD18 AD24 AD36 AD37 EA16 EA24 2H200 FA01 FA14 FA16 FA19 GA18 GA23 GA46 GA54 GA57 GB37 HA01 HA21 HA28 H45 HB14 H04 HB14 H47 HB17 H45 HB14 H47 HB17 HB14 H47 HB17 HB17 H45 HB14 H47 HB17 H45 HB14 H47 HB17 HB14 H47 HB17 HB14 H47 HB17 HB17 HB14 H47 HB17 H45 HB17 MA08 MA11 MA12 MA14 MA20 MB01 MB04 MC01 MC02 MC08 MC11 MC20 NA02 NA06 NA09 NA10

Claims (50)

[Claims] 1. A charging step of charging a photoreceptor as an image carrier, an electrostatic latent image forming step of forming an electrostatic latent image on the charged photoreceptor, and a step of supporting the toner on a toner carrier. An image forming method including at least a developing step of transferring toner to the electrostatic latent image to form a toner image, and a transfer step of electrostatically transferring the toner image formed on the photoconductor in the developing step to a transfer material. The photoreceptor has a conductive support and a photoconductive layer made of an amorphous material having a silicon atom as a matrix, and the toner contains a binder resin, a colorant, and at least zinc oxide. An image containing at least fine particles containing 0.5 to 30 mol% in terms of zinc element and 0.1 to 30 mol% of a metal element other than zinc element with respect to the zinc element in the zinc oxide. Forming method. 2. The image forming method according to claim 1, wherein the metal element other than the zinc element is at least one element selected from aluminum, gallium, indium, tin, and germanium. 3. The image forming method according to claim 1, wherein the element other than zinc is contained in zinc oxide. 4. The image forming method according to claim 1, wherein the fine particles are composed of base particles and zinc oxide supported on the surfaces of the base particles. 5. The image forming method according to claim 4, wherein the base particles are inorganic particles. 6. The image forming method according to claim 4, wherein the base particles are titanium oxide or tin oxide. 7. The resistance of the fine particles is from 1 × 10 ² to 1 × 1.
The image forming method according to claim 1, wherein the image forming method is ⁰⁹ Ωcm. 8. The image according to claim 1, wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner and is 0.05 μm or more. Forming method. 9. The image according to claim 1, wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner and is 0.1 μm or more. Forming method. 10. The release rate of the fine particles in the toner is from 5 to 90%.
The image forming method according to any one of 1. 11. The image forming method according to claim 1, wherein the fine particles are present on the surface of the toner particles in a ratio of 0.3 or more per one toner particle. . 12. The fine particles are 0.
2 to 10% by mass is contained.
12. The image forming method according to any one of 11. 13. The image forming method according to claim 1, wherein the toner further contains magnetic iron oxide. 14. The toner has an average circularity of 0.97.
0 or more, and the strength of magnetization in a magnetic field of 79.6 kA / m (1000 Oersted) is 10 to 50 Am ² / kg.
(Emu / g).
The image forming method according to any one of 1. 15. The toner has a mass average particle diameter of 3 to 10.
15. The image forming method according to claim 1, wherein the image forming method is μm. 16. The photosensitive member further has a surface layer made of an amorphous hydrogenated carbon film.
16. The image forming method according to any one of items 1 to 15. 17. The amount of hydrogen in the amorphous hydrogenated carbon film is 4
The image forming method according to claim 16, which is 1 to 60%. 18. The image forming method according to claim 1, wherein the charging step is a step of charging the photosensitive member by bringing the charging member into contact with the photosensitive member. 19. The image forming method according to claim 18, wherein in the charging step, the charging member and the photoconductor contact each other through the fine particles. 20. The image according to claim 1, wherein transfer residual toner remaining on the photoconductor after the transfer step is collected by the toner carrier in the developing step. Forming method. 21. The charging step is a step of charging the photoconductor in a state where 10 ³ particles / mm ² or more of fine particles are present in a contact portion between the charging member and the photoconductor. The image forming method according to any one of claims 18 to 20. 22. The developing process according to claim 1, wherein the developing process is a non-contact developing method in which the photoconductor and the toner carrier are in non-contact with each other. The image forming method described in 1 .. 23. The Asker C hardness is 2 in the charging step.
23. The image forming method according to claim 1, which is a step of charging the photoconductor by applying a voltage to a roller member of 5 to 50. 24. The charging step is a step of charging the photoreceptor by applying a voltage to a roller member,
At least the surface of the roller member has a dent having an average cell diameter of 5 to 300 μm in terms of sphere, and the porosity of the roller member surface when the dent is a void is 1
The image forming method according to claim 1, wherein the image forming method is 5 to 90%. 25. The charging step according to claim 1, wherein the charging step is a step of charging the photoconductor by applying a voltage to a brush member having conductivity. Image forming method. 26. A charging unit for charging a photoconductor as an image carrier, an electrostatic latent image forming unit for forming an electrostatic latent image on the charged photoconductor, and a charging unit carried on a toner carrier. An image forming apparatus having at least a developing unit that transfers toner to the electrostatic latent image to form a toner image, and a transfer unit that electrostatically transfers the toner image formed on the photoconductor in the developing step onto a transfer material. The photoreceptor has a conductive support and a photoconductive layer made of an amorphous material having a silicon atom as a base, and the toner contains a binder resin, a colorant, and at least zinc oxide. An image containing at least fine particles containing 0.5 to 30 mol% in terms of zinc element and 0.1 to 30 mol% of a metal element other than zinc element with respect to the zinc element in the zinc oxide. Forming equipment. 27. The image forming apparatus according to claim 26, wherein the metal element other than the zinc element is at least one element selected from aluminum, gallium, indium, tin, and germanium. 28. The image forming apparatus according to claim 26, wherein an element other than zinc is contained in zinc oxide. 29. The image forming apparatus according to claim 26, wherein the fine particles are composed of base particles and zinc oxide supported on the surfaces of the base particles. 30. The image forming apparatus according to claim 29, wherein the base particles are inorganic particles. 31. The image forming apparatus according to claim 29, wherein the base particles are titanium oxide or tin oxide. 32. The resistance of the fine particles is from 1 × 10 ² to 1 ×.
32 to 31 which is 10 ⁹ Ωcm.
The image forming apparatus according to claim 1. 33. The image according to claim 26, wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner, and is 0.05 μm or more. Forming equipment. 34. The image according to claim 26, wherein the volume average particle diameter of the fine particles is smaller than the volume average particle diameter of the toner and is 0.1 μm or more. Forming equipment. 35. The release rate of the fine particles in the toner is 5 to 90%.
The image forming apparatus according to any one of 34. 36. The image forming apparatus according to claim 26, wherein the fine particles are present on the surface of the toner particles in a ratio of 0.3 or more per one toner particle. . 37. The fine particles have a particle size of 0.
27 to 20% by mass is contained.
37. The image forming apparatus according to any one of 36 to 36. 38. The image forming apparatus according to claim 26, wherein the toner further contains magnetic iron oxide. 39. The toner has an average circularity of 0.97.
0 or more, and the magnetization intensity in a magnetic field of 79.6 kA / m (1000 Oersted) is 10 to 50 Am ² / kg.
(Emu / g). 26 to 3 characterized in that
8. The image forming apparatus according to any one of items 8. 40. The toner has a mass average particle diameter of 3 to 10.
40. The image forming apparatus according to claim 26, wherein the image forming apparatus has a thickness of μm. 41. The photoreceptor according to claim 2, further comprising a surface layer formed of an amorphous hydrogenated carbon film.
The image forming apparatus according to any one of 6 to 40. 42. The hydrogen content of the amorphous hydrogenated carbon film is 41 to 60% in terms of element ratio.
The image forming apparatus described. 43. The charging means charges the charging member by bringing the charging member into contact with the photosensitive member.
The image forming apparatus according to claim 2. 44. The image forming apparatus according to claim 43, wherein in the charging means, the charging member and the photoconductor are in contact with each other through the fine particles. 45. The image forming apparatus according to claim 26, wherein the transfer residual toner remaining on the photoconductor after the transfer is collected by the toner carrying member of the developing unit. apparatus. 46. The charging unit charges the photosensitive member in a state where 10 ³ particles / mm ² or more of fine particles are present in a contact portion between the charging member and the photosensitive member. The image forming apparatus according to any one of 43 to 45. 47. The developing device according to claim 26, wherein the developing device develops by a non-contact developing method in which the photosensitive member and the toner carrying member are in non-contact with each other. Image forming apparatus. 48. The charging means has an Asker C hardness of 2
48. The photosensitive member is charged by applying a voltage to a roller member of 5 to 50.
The image forming apparatus according to claim 1. 49. The charging means charges the photoconductor by applying a voltage to a roller member, and at least the surface of the roller member has an average cell diameter of 5 or less as spherical.
49. The roller member has a void having a diameter of 300 μm, and the void ratio of the roller member surface when the void is a void portion is 15 to 90%. Image forming apparatus. 50. The image forming apparatus according to claim 26, wherein the charging unit charges the photosensitive member by applying a voltage to a brush member having conductivity. .