JP2004246346A - Toner and image forming apparatus using the toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner and a developer which can be used in a toner recycling system without causing deformation or breaking of the toner, with little change in a surface condition of the toner, are free from a degradation in lasting quality of the developer, fogging, lowering of image density, stain on the background of the image, and toner change with environment, etc., and provide good image quality, and to provide an image forming apparatus and a detachable process cartridge. <P>SOLUTION: The toner is used in an image forming method adopting a toner recycling system, contains at least a modified polyester resin, a colorant and a release agent, and has a volume average particle diameter (Dv) of 4.0-6.0 μm, a ratio of (Dv) to (Dn) (Dv/Dn) of 1.00-1.30, wherein (Dn) represents a number average particle diameter and a shape factor SF-1 of 140-200. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to an image forming method using an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like, and a toner, a developer, a toner container, and an image forming method used in an image forming method employing a toner recycling system. The present invention relates to a device (developing device) and a process cartridge.

In electrophotography, an electrostatic latent image is generally formed on a surface of a latent image carrier (hereinafter also referred to as a photoconductor) having a photosensitive layer made of a photoconductive material by charging and exposure, and then the electrostatic latent image is formed. Is developed by a toner that is a colored particle, and the obtained toner image is usually transferred to a recording material such as paper, and then fixed to form a copy image.
As a method for fixing the toner, various methods have been conventionally known. In particular, a heat roller fixing method is adopted from the viewpoint of high thermal efficiency and high-speed fixing. The toner applied to the heat roller fixing method basically has (1) that the toner can be reliably fixed at a low temperature, that is, it has excellent low-temperature fixability, and (2) the molten toner transfers to the heat roller at the time of fixing. It is required to be difficult, that is, to have excellent hot offset properties.

  Further, in order to form a clear copy image, it is necessary that the toner can be stably present as a powder without agglomeration in a use or storage environment, that is, the toner must have excellent storage stability. Further, in order to stably form a good image without fogging many times, it is necessary that the toner has a performance that is hard to be broken by a mechanical impact or a pressure in a developing device.

Recently, in an image forming apparatus for developing a latent image formed on a photoconductor with toner, a cleaner for removing toner remaining on the photoconductor drum after transfer and a recycling apparatus for returning the toner removed by the cleaner to the developing apparatus. (See Patent Document 1).
However, when the toner is used in an image forming apparatus employing a recycling system, problems such as a decrease in image density, background stain on paper, fog, and carrier adhesion tend to occur as the number of copy images increases. This is because the toner undergoes deformation and destruction due to the shearing force received in the recycling process, and the charging ability of the toner is reduced, and at the same time, the charge-imparting ability of the carrier is reduced by the toner fine powder generated. Also, in black-and-white copying in which oil-less toner has become mainstream, wax contained as a release agent bleeds out on the surface of toner particles due to heat in an image forming apparatus, toner stress in a cleaning or toner recycling system, and adheres to a carrier. As a result, a reduction in charging occurs.

  As a toner loaded on such a recycling system, a toner containing a crosslinked polyester resin as a binder resin is known (for example, see Patent Documents 2 to 7). However, when these toners are frequently subjected to mechanical external force such as agitation in the developing device due to recycling of the toner, the toner particles are destroyed and fine particles are easily generated, and the fine particles contaminate the carrier particles and cause the carrier particles to be contaminated. As a result, a toner having an insufficient charge amount is generated, and the toner contaminates a developer carrier and other devices, thereby deteriorating the developing property.

  In the study of the recycling system, not only the study of toner but also the study and development of an image forming method have been performed. Also, various ideas and improvements have been made in the image forming apparatus. For example, in an electrostatic image forming process, an attempt has been made to reuse the residual toner on the image carrier after being transferred to a receiving medium. The residual toner is accumulated in a collection-only bottle or the like, and the bottle has been disposed of as industrial waste. Such disposal is one that pollutes the global environment, wastes resources, and is not preferred. Therefore, a toner recycling method for eliminating all such toner waste and using all toner has been studied.

  For example, a technique is provided in which a transport path for transporting the collected toner from the cleaning device to the developing device is used, and the toner is used as a part of toner supplied to the developing device (see Patent Document 8). (See Patent Document 9), and when a rotating member capable of applying a bias is provided and a region corresponding to the paper passing portion of the carrier passes, the toner is recovered by electrostatic force and is transferred to the non-paper passing portion. It is disclosed that when a corresponding area passes, toner is attached to an image carrier (see Patent Document 10).

  However, each of these techniques has disadvantages and has not been satisfactory. Further, the technology described in Patent Document 8 requires a toner conveying path such as a pipe, and further requires a toner conveying means such as a screw or a belt, so that the apparatus becomes large and complicated. The toner described in Patent Document 9 is difficult to collect the toner once adhered to the image carrier as the transfer residual toner by the developing device, and adheres to the image carrier, or is often interrupted even during image formation, and stains on the background portion. And stains on the image area often occur. In addition, it is difficult to cope with an abnormal situation such as a paper jam, and often adversely affects a process after the image carrier is soiled. These descriptions are only a part, and various other reports have been made, and none are satisfactory.

On the other hand, strong demands for higher image quality from the market have spurred the development of electrophotographic devices suitable for the devices and toner developers used therein. It is desirable that the toner corresponding to high image quality is a spherical toner having a small particle size and a narrow particle size distribution. When the particle diameter distribution of the toner is sharp and spherical, the behavior of the individual toner particles during development is uniform, and the reproducibility of fine dots is significantly improved.
However, a toner having a small particle diameter and a uniform particle diameter is more disadvantageous for the toner when used in a recycling system. In the case of a recycling system, first, there is a difficulty in cleaning. Particularly in blade cleaning, it is difficult to stably clean toner having a uniform and small particle diameter. Under such circumstances, various methods have been proposed for improving the cleaning property by devising the toner. One of the methods is to change the toner from spherical to irregular. By changing the shape of the toner, the fluidity of the powder of the toner is reduced, and damping is easily performed by blade cleaning. However, if the degree of the irregular shape of the toner is too large, the behavior of the toner becomes unstable at the time of development or the like, and the fine dot reproducibility is deteriorated.

As described above, by deforming the toner, the reliability for cleaning is certainly improved, but on the other hand, there is a problem in fixing. That is, when the shape of the toner is deformed, the filling density of the toner in the toner layer on the transfer material before fixing is reduced, and the heat conductivity in the toner layer during fixing is reduced, and the low-temperature fixability is deteriorated. Resulting in. In particular, when the pressure at the time of fixing is smaller than the conventional pressure, thermal conductivity is further deteriorated, and low-temperature fixing is hindered.
For example, a toner made of polyester having a Wadell practical sphericity of 0.90 to 1.00 has been proposed (see Patent Document 11). However, since the toner is substantially spherical, the above-described problem of cleaning has been solved. Absent.

  As described above, the toner containing polyester, which is synthesized by a polymerization method and has a high degree of circularity, does not have sufficient recyclability, and merely deforming the toner shape can support high image quality and achieve sufficient recycling. There is a problem that it is not possible to obtain a toner having good properties.

JP-A-60-41079 JP-A-59-14144 JP-A-58-14147 JP-A-60-176049 JP-A-60-176054 JP-A-62-127748 JP-A-62-127749 JP-A-63-246780 JP-A-1-118774 JP-A-6-51672 JP-A-11-133665 (Claim 1, page 27, left column, lines 27 to 32)

An object of the present invention is to solve the above-described conventional problems and achieve the following objects. That is, the present invention
(1) Adopted in the toner recycling system, it does not cause deformation and destruction of the toner, changes in the surface condition of the toner are small, and reduces the durability quality of the developer, fog, image density, background contamination, toner environment fluctuation, etc. To provide a toner and a developer, which can provide good image quality, an image forming apparatus, and a detachable process cartridge, which do not generate the image.
(2) To provide a toner and a developer capable of obtaining high-quality image with excellent fine dot reproducibility. In particular, to provide a toner and a developer that can obtain high reliability in cleaning,
(3) To provide a toner and a developer excellent in low-temperature fixability;
(4) To provide a toner and a developer that can satisfy both the above-mentioned problems (1) to (3);
(5) An object of the present invention is to provide a toner which is excellent in transfer efficiency and has a small amount of untransferred toner and can obtain a high quality image.

As a result of intensive studies on means for simultaneously satisfying the toner recyclability and low-temperature fixability described above, the main component of the binder resin of the toner was a polyester resin, and the particle size, particle size distribution, and shape were determined. It has been found that this problem can be solved by adjusting the coefficient, and finally the present invention has been completed. That is,
<1> A toner used in an image forming method employing a toner recycling system and containing at least a modified polyester resin, a colorant, a release agent, and a coating, wherein the volume average particle diameter (Dv) of the toner is 4.0 to 6.0 μm, the ratio Dv / Dn of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.00 to 1.30, and the toner has a shape factor SF -1 is 140 to 200.
<2> a step of dissolving or dispersing a composition containing at least a resin capable of reacting with a compound having an active hydrogen group, a colorant and a release agent in an organic solvent;
A step of dispersing the solution or dispersion in an aqueous medium while causing a resin capable of reacting with a compound having an active hydrogen group to undergo at least one of extension and crosslinking.
Removing the organic solvent after or during the reaction of at least one of the extension and crosslinking,
The toner according to <1>, which is obtained by a production method having the following.
<3> The toner according to <2>, wherein the composition contains a compound having an active hydrogen group.
<4> The toner according to <2>, wherein the compound having an active hydrogen group is added in a step of dispersing the compound in an aqueous medium.
<5> The toner according to any one of <2> to <4>, wherein the aqueous medium contains polymer fine particles and is capable of forming the coating.
<6> The toner according to any one of <1> to <5>, wherein the toner ratio Dv / Dn is 1.00 to 1.20.
<7> The toner according to any one of <1> to <6>, wherein the shape factor SF-1 of the toner is 150 to 180.
<8> The toner according to any one of <1> to <7>, wherein the content of the fine powder having a particle diameter of 2 μm or less is 15% or less on a number basis in the particle size distribution measured by a flow type particle image measuring device of the toner. Toner.
<9> The toner according to any one of <1> to <8>, wherein the toner has an average circularity measured by a flow type particle image analyzer of 0.90 to 0.95.
<10> The toner according to <5>, wherein the polymer fine particles have a glass transition point of 50 to 110 ° C.
<11> The polymer fine particles are selected from vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, melamine resin, urea resin, aniline resin, ionomer resin and polycarbonate resin. The toner according to any one of the above items <5> and <10>, wherein the toner contains at least one resin.
<12> The toner according to any one of <5> and <10> to <11>, wherein the polymer fine particles have a volume average particle diameter of 10 to 200 nm.
<13> Before the step of removing the organic solvent, the step <2> including a step of stirring the obtained dispersion liquid in a stirring tank equipped with a stirrer having a peripheral speed of 5 m / s or more to deform the spherical particles into a spindle shape. It is a toner of the description.
<14> The toner according to any one of <1> to <13>, wherein the modified polyester resin is a urea-modified polyester resin.
<15> The toner according to any one of <1> to <14>, further including an unmodified polyester resin.
<16> The toner according to <15>, wherein the unmodified polyester resin has a glass transition point of 40 to 70 ° C.
<17> The toner according to any one of <15> to <16>, wherein the unmodified polyester resin has an acid value of 1 to 30 mgKOH / g.
<18> The toner according to any one of <1> to <17>, which is a toner used for a two-component developer.
<19> A toner used in an image forming method employing a toner recycling system, including a toner and a carrier, wherein the toner contains at least a modified polyester resin, a colorant, a release agent, and a coating. The volume average particle diameter (Dv) of the toner is 4.0 to 6.0 μm, and the ratio Dv / Dn between the volume average particle diameter (Dv) and the number average particle diameter (Dn) is 1.00 to 1.30. And the shape factor SF-1 of the toner is 140 to 200.
<20> A photoreceptor, a charging unit for charging the photoreceptor, an exposure unit for exposing the photoreceptor to form an electrostatic latent image, and a toner loaded therein. Developing means for developing to form a toner image, transfer means for transferring the toner image carried on the photoreceptor to a transfer material, and cleaning means for cleaning the toner remaining on the photoreceptor surface after the transfer using a blade And a recycling means for reusing the cleaned toner for development,
An image forming apparatus, wherein the toner is the toner according to any one of <1> to <18>.
<21> The image forming apparatus according to <20>, wherein the photoconductor is an amorphous silicon photoconductor.
<22> The image forming apparatus according to any one of <20> to <21>, wherein an alternating electric field is applied when a latent image on the photoconductor is developed.
<23> The image according to any one of <20> to <22>, wherein the charging device is a charging device that performs charging by bringing the charging member into contact with the latent image carrier and applying a voltage to the charging member. It is a forming device.
<24> Photoreceptor, charging means for charging the photoreceptor, developing means loaded with toner, developing the electrostatic latent image using toner to form a toner image, and remaining on the photoreceptor surface after transfer A process cartridge which is integrally provided with at least one means selected from cleaning means for cleaning the formed toner using a blade, and which is detachable from the image forming apparatus main body. <18> A process cartridge, which is the toner according to any one of <18> to <18>.
<25> a charging step of charging the photoconductor, an exposure step of exposing the photoconductor to form an electrostatic latent image, a toner being loaded, and developing the electrostatic latent image using the toner to form a toner image A transfer step of transferring a toner image carried on the photoconductor to a transfer material; a cleaning step of cleaning toner remaining on the photoconductor surface after the transfer using a blade; A recycling process for recycling the developed toner for development,
An image forming method, wherein the toner is the toner according to any one of <1> to <18>.
<26> A toner used in an image forming method employing a toner recycling system and containing at least a modified polyester resin, a coloring agent, and a release agent, wherein the toner has a surface coated with a fine particle polymer, and the toner Has a volume average particle diameter (Dv) of 4.0 to 6.0 μm and a ratio Dv / Dn of the volume average particle diameter (Dv) to the number average particle diameter (Dn) of 1.00 to 1.30. And the toner has a shape factor SF-1 of 140 to 200.

  That is, according to the present invention, a toner and a developer having excellent recyclability can be provided, and the present invention is applied to an oilless fixing type image forming apparatus having a recycling mechanism for returning the collected toner from the cleaning unit to the developing unit. By loading the two-component developer containing the toner of the present invention, an image forming apparatus excellent in recyclability is realized.

According to the present invention, a conventional problem can be solved,
(1) Adopted in the toner recycling system, it does not cause deformation and destruction of the toner, changes in the surface condition of the toner are small, and reduces the durability quality of the developer, fog, image density, background contamination, toner environment fluctuation, etc. A toner and a developer capable of obtaining good image quality without causing the image, an image forming apparatus and a detachable process cartridge,
(2) To provide a toner and a developer capable of obtaining high-quality image with excellent fine dot reproducibility. In particular, toner and developer that can obtain high reliability in cleaning,
(3) toner and developer excellent in low-temperature fixability,
(4) a toner and a developer that can satisfy the characteristics of the above (1) to (3);
(5) It is possible to provide a toner excellent in transfer efficiency and capable of obtaining high-quality images with little transfer residual toner.

Hereinafter, the image forming method of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a digital copying machine as an example of an image forming apparatus used in the present invention, which uses a well-known electrophotographic method and includes a drum-shaped photosensitive member (1) inside (for example, MF7070 manufactured by Ricoh).
Around the photoreceptor (1), a charger (2), an exposure unit (3), a developing unit (4), and a transfer unit (5) for performing an electrophotographic copying process along a rotation direction indicated by an arrow (A). ), And a cleaning means (6). Exposure means (3) forms an electrostatic latent image on photoreceptor (1) based on an image signal read by reading means (8) from a document placed on document table (7) on the top surface of the copying machine. I do. The electrostatic latent image formed on the photoreceptor (1) is converted into a toner image by a developing unit (4), and the toner image is transferred to a transfer sheet fed from a paper feeding device (9). ) Is electrostatically transferred. The transfer paper on which the toner image is placed is conveyed to the fixing means (10) and fixed, and then discharged out of the apparatus.

  Next, the movement of the toner used in the image forming process will be described with reference to FIGS. The developing device (4) is a two-component developing device and has a developing tank (40) containing a developer composed of a carrier and a toner. When the developing device (4) forms a toner image, the toner of the developer is consumed, and the ratio (toner density) decreases. Therefore, in order to suppress a decrease in image density, when the potential Vt corresponding to the toner density in the developer becomes a predetermined value or more with respect to the potential Vref corresponding to the target toner density value (that is, the toner density is equal to or less than the predetermined value). The toner is supplied from the toner hopper (41) to maintain the toner concentration in the developer. The toner concentration in the developer is measured by a magnetic permeability sensor (42) attached to the lower case of the developing device. The potential Vref corresponding to the target value of the toner density is set by a value Vsp obtained by measuring a measurement toner image (P pattern) formed on the photoconductor with a photosensor. The toner supplied from the toner hopper (41) via the supply roller (43) is agitated and frictionally charged with the carrier by the agitating member (44) in the developing device (4). The developer including the carrier and the toner is jumped up to the developing roller (46) by the paddle wheel (45), and is attracted onto the developing roller (46) by the magnet in the developing roller (46). The developer is transported by the sleeve on the outer periphery of the developing roller, and the excess is scraped off by the developing doctor (47). The toner in the developer conveyed to the photoreceptor adheres to the electrostatic latent image by a developing bias.

  The toner adhered on the photoreceptor (1) by the development is electrostatically transferred to transfer paper by the transfer means (5), but about 10% of the toner remains untransferred on the photoreceptor. The untransferred toner is scraped off from the photoreceptor by a cleaning blade (6a) or a brush roller (6b) of the cleaning means (6), and the scraped recovered toner is reused as a recycled toner (T). For this reason, it falls under its own weight from the discharge port (6c), and is conveyed to the transport pipe composed of the connected transport pipe (13a) and the rotary screw conveyor (13b) in this pipe in the recycling device (13) shown in FIG. Sent. The pipe and the screw are made of a metal such as aluminum or stainless steel or a resin. The toner conveyed by the screw is returned to the developing means (4) as recycled toner.

  On the other hand, a cleaning unit (11) is also provided on the transfer belt (5a) of the transfer unit (5) because toner adheres to the transfer belt (5a) in a non-transferred portion or a non-image portion. The residual toner on the transfer belt (5a) is scraped off by a cleaning blade (not shown) that slides on the belt. Since the scraped-off toner is likely to contain foreign matter such as paper dust, in this example, the toner is dropped from the discharge port without being recycled and collected via the toner guide screw pipe (dotted line). The waste toner is sent to the tank (12).

  In the present invention, in an image forming apparatus having a toner recycling mechanism having a large amount of thermal stress and mechanical stress, polymer fine particles having a specific particle size and particle size distribution of the present invention and being a preferable embodiment of the present invention. A toner in which the toner particles are coated with polymer fine particles on the surface, which is obtained by manufacturing in an aqueous medium in which is dispersed, exerts a great effect on the stress. More specifically, it is intended to prevent a reduction in charge due to seepage of the wax onto the particle surface due to the release agent effect and a decrease in charge due to adhesion to a carrier. When a thermal stress is applied to the developer, the wax comes out on the toner surface, and the amount of the wax becomes excessive, and the wax adheres to the carrier surface. As a result, when the toner polarity is negative, a phenomenon that the charge amount of the developer decreases due to the wax having the same polarity adhering to the carrier occurs. Recently, there has been a demand for further low-temperature fixing, high-definition, and high-quality images with the aim of further improving quality. Toner particles have a small particle size, sharp particle size distribution, and low softening. The rate of exposure is increasing, and it is disadvantageous for toner in the recycling organization. In the present invention, there is provided a toner having a small particle size, a sharp particle size distribution, a spherical shape, and a cleaning property, and excellent in storability and releasability despite lowering of Tg of the toner to achieve lower temperature fixing. I do.

When the ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) of the toner of the present invention is 1.00 to 1.30, a high-resolution and high-quality toner is obtained. It becomes possible. Further, in the case of the two-component developer, even if the toner balance is performed for a long time, the fluctuation of the particle diameter of the toner in the developer is reduced, and good and stable developability can be obtained even when the developing device is stirred for a long time. Can be If Dv / Dn exceeds 1.30, the dispersion of the particle size of each toner particle is large, and the behavior of the toner varies during development and the like, and the reproducibility of minute dots is impaired. As a result, high-quality images cannot be obtained. More preferably, Dv / Dn is in the range of 1.00 to 1.20, and a better image can be obtained.
The volume average particle size Dv is preferably 4.0 to 6.0 μm. In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning performance. is there.

Further, when the volume average particle diameter is smaller than the above range, in the case of a two-component developer, the toner is fused to the surface of the carrier during long-term stirring in the developing device, and the charging ability of the carrier is reduced, or the one-component developer When it is used, the filming of the toner on the developing roller and the fusion of the toner to a member such as a blade for thinning the toner are likely to occur. Further, these phenomena are greatly related to the content of the fine powder. Particularly, when the particle size of 3 μm or less exceeds 10%, it becomes a hindrance to adhere to a carrier or to achieve a high level of charge stability. Conversely, if the particle size of the toner is larger than the above range, it becomes difficult to obtain a high-resolution image with high resolution, and the particle size of the toner in the case where the balance of the toner in the developer is performed. In many cases. It was also found that the same was true when the volume average particle diameter / number average particle diameter was larger than 1.30.
As described above, a toner having a small particle diameter and a uniform particle diameter causes difficulty in cleaning properties and recyclability. Therefore, the range of the shape factor SF-1 of the toner is preferably 140 to 200.

  First, the relationship between toner shape and transferability will be described. When using a full-color copying machine that allows transfer by multi-color development, the amount of toner on the photoconductor increases compared to the case of a single-color black toner used in a black-and-white copying machine. Then, it is difficult to improve the transfer efficiency.

  From the viewpoint of the balance between the blade cleaning and the transfer efficiency, the toner has a shape factor SF-1 of 140 to 200, preferably 150 to 180, so that both the cleaning and the transferability can be achieved. Cleaning and transferability are greatly related to the material of the blade and the manner in which the blade is applied, and the transfer also differs depending on the process conditions, so that a design according to the process can be made within the range of SF-1. However, when SF-1 is lower than 140, cleaning becomes difficult with a blade. When SF-1 exceeds 200, the above-mentioned deterioration of transferability is observed. This phenomenon is because the toner shape is deformed, the movement of the toner during transfer (from the surface of the photoreceptor to the transfer paper, etc.) is not smooth, and the behavior of the toner particles varies, so that uniform and high transfer efficiency is obtained. Can not be obtained. In addition, unstable charging and fragility of the particles begin to appear. Further, a fine powder phenomenon occurs in the developer, which causes a decrease in the durability of the developer.

The shape of the toner is preferably a spindle shape within a shape factor SF-1 of 140 to 200. The spindle type is excellent in transferability next to the spherical shape because the surface has few large irregularities. The cleaning property and the recyclability, which are in a trade-off relationship with the transfer property, are also good, and it can be said that the shape is very balanced. In the case of the recycling system, as the SF-1 is closer to a true sphere, the transferability and the toner transporting property are better, but in the case of blade cleaning, toner cleaning failure occurs and eventually the situation cannot be recycled.
On the other hand, when SF-1 exceeds 200, shape change and pulverization during transportation occur, and further, toner deterioration due to poor charging or aggregation occurs, which is not preferable.
The optimum shape factor SF-1 in the recycling system is 140 to 200. In conventional suspension polymerization and emulsion polymerization, the solvent removal step is different from that of the present invention, and shape control is difficult.

-Toner shape-
In the present invention, SF-1 indicating the shape factor of the toner is a conventionally known coefficient. For example, SF-1 is obtained by using a FE-SEM (S-800) manufactured by Hitachi, Ltd. to enlarge a toner image magnified 500 times. One hundred samples are randomly sampled, and the image information can be obtained by, for example, introducing into an image analyzer (Luzex III) manufactured by Nicole via an interface and performing analysis.

  The average circularity measured by the flow type particle image analyzer and the toner used in the particle recycling system having a particle size of 2 μm or less require a toner shape and a flow type particle image in order to maintain high image quality and long-term cleanability and recyclability. It is necessary to limit the content of particles of 2 μm or less by the analyzer.

In addition, maintenance of long-term cleaning properties in repeated use, prevention of the toner being fused to the surface of the carrier during long-term stirring in the developing device when used as a two-component developer, and a reduction in the charging ability of the carrier, and When used as a one-component developer, in order to prevent filming of the toner on the developing roller and fusion of the toner to a member such as a blade for thinning the toner, a flow type particle image analyzer is used. It was found that it is effective that the number of particles having a size of less than 2.0 μm in a number-equivalent circle measured by the method described above is 15% by number or less.
This is because the Coulter Counter (TAII) measures the change in resistance with an electric signal, so particles of 2 μm or less are greatly affected by noise, and measurement accuracy is lacking. By using a flow-type particle image analyzer, measurement of fine particles of 2 μm or less is possible, and by reducing fine particles having a diameter of 2 μm or less corresponding to a circle measured by the flow-type particle image analyzer (hereinafter, ultrafine toner), It has been found that the toner does not stick to the conveyance system for a long time in repeated use.
Further, when the circularity is 0.95 or more, that is, when there are many round particles, the contact-type cleaning method causes particles to pass through, and the cleaning property cannot be maintained for a long time.

In the present invention, the flow-type particle image used in the measurement of the particles, the circle-equivalent diameter of the image and the number% in each circularity can be measured using a flow-type particle image analyzer FPIA-2100 manufactured by SYSMEX CORPORATION. An outline of the apparatus and the measurement is described in JP-A-8-136439. The measurement is performed by adjusting a 1% aqueous solution of NaCl using primary sodium chloride and then adding 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, as a dispersant to 50 to 100 ml of a 0.45 μm-filtered liquid. In addition, add 1-10 mg of sample. This was subjected to a dispersion treatment for 1 minute using a table-top ultrasonic cleaner (VS-150: manufactured by VELVO-CLEAR), and the measurement was performed using a dispersion liquid in which the particle concentration was adjusted to 5000 to 15000 particles / μl. The measurement of the number of particles is performed by calculating the diameter of a circle having the same area as the area of a two-dimensional image picked up by a CCD camera as an equivalent circle diameter.
Based on the accuracy of the CCD pixels, measurement data of particles was obtained with a circle equivalent diameter of 0.6 μm or more effective. When the particle size is measured by a flow type particle image analyzer, the particle size is 2 μm or less more accurate than the Coulter method.

-Toner particle size-
The average particle size and the particle size distribution of the toner are determined by a Car Coulter counter method. Examples of an apparatus for measuring the particle size distribution of toner particles include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter Corporation). In the present invention, the measurement was performed using a Coulter Counter TA-II connected to an interface (Nikkagiken) for outputting the number distribution and volume distribution and a PC9801 personal computer (manufactured by NEC).

The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably an alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolyte is prepared by preparing an approximately 1% NaCl aqueous solution using primary sodium chloride, and for example, ISOTON-II (manufactured by Coulter Inc.) can be used. Here, 2 to 20 mg of the measurement sample is further added. The electrolytic solution in which the sample was suspended was subjected to a dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and the volume and the number of toner particles or toner were measured by using the measuring device with a 100 μm aperture as an aperture. Calculate volume distribution and number distribution.

As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 8.35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; 12.70 to less than 16.00 μm; 16.00 to less than 20.20 μm; Less than 40 μm; 25.40 to less than 32.00 μm; using 13 channels of 32.00 to less than 40.30 μm, and targeting particles having a particle size of 2.00 μm or more to less than 40.30 μm.
The volume-based volume average particle size (Dv) obtained from the volume distribution according to the present invention, the number average particle size (Dn) obtained from the number distribution, and the ratio Dv / Dn were obtained.

-Resin fine particles-
The resin fine particles used in the present invention have a glass transition point (Tg) of preferably from 50 to 110 ° C, more preferably from 50 to 90 ° C. Of the toner, or the probability of sticking and agglomeration in the toner collection path during recycling increases. When the glass transition point (Tg) is higher than 110 ° C., the resin fine particles hinder the adhesion to the fixing paper, and the fixing lower limit temperature increases. A more preferred range is 50 to 70 ° C.
The weight average molecular weight is desirably 100,000 or less. Preferably it is 50,000 or less. The lower limit is usually 4000. When the weight average molecular weight exceeds 100,000, the resin fine particles hinder the adhesion to the fixing paper, and the minimum fixing temperature rises.

  As the resin fine particles, known resins can be used as long as they can form an aqueous dispersion, and a thermoplastic resin or a thermosetting resin may be used. Examples thereof include a vinyl resin, a polyurethane resin, an epoxy resin, and a polyester resin. . As the resin fine particles, two or more of the above resins may be used in combination. Among these, those comprising a vinyl-based resin, a polyurethane resin, an epoxy resin, a polyester resin or a resin used in combination thereof are preferable because an aqueous dispersion of fine spherical resin particles is easily obtained.

As the vinyl resin, a polymer obtained by homopolymerizing or copolymerizing a vinyl monomer, for example, a styrene- (meth) acrylate resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylate polymer, Styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, styrene- (meth) acrylic acid copolymer and the like can be mentioned.
The volume average particle size of the resin fine particles is 10 to 200 nm, preferably 20 to 80 nm, as measured by a light scattering photometer (manufactured by Otsuka Electronics Co., Ltd.).

-Hot offset property-
Regarding the hot offset resistance, various studies have been made to control the molecular weight distribution of the binder resin. In order to achieve the opposite properties of low-temperature fixability and hot offset resistance, for example, a binder resin having a wide molecular weight distribution is used, or a polymer component having a molecular weight of hundreds of thousands or millions of In this method, several thousand to tens of thousands of low molecular components are mixed with a resin having at least two molecular weight peaks, and the functions of the respective components are separated. When the polymer component has a crosslinked structure or is in a gel state, it is more effective for hot offset.

The molecular weight distribution of the binder component (resin component) in the toner is measured by the following method.
After about 1 g of the toner is precisely evaluated in an Erlenmeyer flask, 10 to 20 g of THF (tetrahydrofuran) is added to obtain a THF solution having a binder concentration of 5 to 10%. The column is stabilized in a heat chamber at 40 ° C., and THF at a flow rate of 1 ml / min is passed through the column at this temperature, and 20 μl of the THF sample solution is injected. The molecular weight of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from a monodisperse polystyrene standard sample and the retention time. A calibration curve is created using a polystyrene standard sample. As the monodisperse polystyrene standard sample, for example, one having a molecular weight in the range of 2.7 × 10 ^{2 to} 6.2 × 10 ⁶ manufactured by Tosoh Corporation is used. A refractive index (RI) detector is used for the detector. As a column, for example, a combination of TSKgel, G1000H, G2000H, G2500H, G3000H, G4000H, G5000H, G6000H, G7000H, and GMH manufactured by Tosoh Corporation is used.

The main peak molecular weight (Mp) of the THF-soluble resin is usually from 2,500 to 10,000, preferably from 2,000 to 8,000. When the amount of the component having a molecular weight of less than 2500 increases, the heat-resistant storage stability tends to deteriorate, and when the component having a molecular weight of more than 10,000 increases, the low-temperature fixability tends to decrease. The content of the component having a molecular weight of more than 10,000 is 1% to 10%, and varies depending on the toner material, but is preferably 3 to 6%. If it is less than 1%, sufficient hot offset resistance cannot be obtained, and if it is 10% or more, glossiness and transparency may deteriorate. The content of the component having a molecular weight of less than 2500 is 0.1 to 5.0%.
The number average molecular weight (Mn) of the THF-dissolved resin is preferably 2000 to 15000, and the value of Mw / Mn (Mw: weight average molecular weight) is preferably 5 or less. If it exceeds 5, sharp melt properties are lacking and gloss is impaired. Use of a polyester resin containing 1 to 25% of a THF-insoluble component leads to improvement in hot offset.

-Binder resin-
Conventional general materials can be used as the binder resin. Conventionally, as a binder resin used in the production of toner, for example, polyester resin, styrene resin, acrylic resin, epoxy resin, and the like, in a normal toner, among these, from the copolymer of styrene and acrylate Resin is most commonly used. On the other hand, a low-temperature fixing toner is a resin that easily satisfies the above-described thermal characteristics. Polyester resins are excellent in low-temperature fixability and storage stability because the binder resin has a low softening temperature and a high glass transition point. Further, since the affinity between the polyester resin and the ester bond and the paper is good, a toner having excellent offset resistance can be obtained.

  The polyester resin used as a main component of the binder resin of the toner for developing an electrostatic image of the present invention is synthesized by a condensation reaction of an acid component and an alcohol component, a ring opening reaction of a cyclic ester, or a halogen compound. And an alcohol component and carbon monoxide. In the method for producing a toner for developing an electrostatic image of the present invention, the above-mentioned monomer which is a synthetic material of a polyester resin is polymerized in combination, whereby the toner for developing an electrostatic image of the present invention having the above-mentioned excellent physical properties is obtained. A toner can be easily obtained. Hereinafter, various monomers used as a synthetic material of the polyester resin will be described.

  First, as the alcohol component and the acid component, those having a valency of 2 or more are suitably used. For example, as the dihydric alcohol, ethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1, Diols such as 5-pentanediol and 1,6-hexanediol; bisphenol A, hydrogenated bisphenol A, α, α'-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene, polyoxyethylenated bisphenol A And bisphenol A alkylene oxide adducts such as polyoxypropylene bisphenol A.

  Examples of the trihydric or higher alcohol include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, sucrose, 1,2,4-butanetriol, 1,2,2 5-pentatriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butaneditriol, trimethylolmethane, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. Is mentioned.

  Examples of the divalent acid include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonate Acids, and other divalent organic acids. Examples of the trivalent acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, and 2,5,7-naphthalenetricarboxylic acid. 1,2,5-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-carboxymethylpropane, tetra (carboxymethyl) methane, 1,2,7 , 8-octanetetracarboxylic acid and the like. Acid anhydrides and acid halides of these organic acids are also preferred acid components in terms of synthesis.

  As the compound corresponding to the other acid component, a halogen compound can be used. As the halide, a polyhalogen compound is used. For example, cis-1,2-dichloroethene, trans-1,2-dichloroethene, 1,2-dichloropropene, 2,3-dichloropropene, 1,3- Dichloropropene, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, o-dibromobenzene, m-dibromobenzene, p-dibromobenzene, o-chlorobromobenzene, dichlorocyclohexane, dichloroethane, 1,4-dichlorobutane , 1,8-dichlorooctane, 1,7-dichlorooctane, dichloromethane, 4,4'-dibromovinylphenol, 1,2,4-tribromobenzene and the like.

In the present invention, it is preferable to use, as a synthetic component of the polyester resin, one having at least an aromatic ring in one of the above-mentioned acid component and alcohol component.
The use ratio of the acid component to the alcohol component is in the range of 0.9 to 1.5 molar equivalents, preferably 1.0 to 1.3 molar equivalents, for 1 molar equivalent of the carboxyl group. preferable. Here, the carboxyl group includes a halogen compound which is a compound corresponding to the above-mentioned acid component. As another additive, an amine component may be used. Specific examples include triethylamine, trimethylamine, N, N-dimethylaniline and the like. Further, the reaction may be performed using another condensing agent, for example, dicyclohexylcarbodiimide.

-Modified polyester capable of reacting with active hydrogen groups-
A reactive modified polyester resin (RMPE) capable of reacting with an active hydrogen group (hereinafter, the polyester resin is also simply referred to as polyester) includes, for example, a polyester resin having a functional group capable of reacting with an active hydrogen group such as an inocyanate group. Polymers and the like. The polyester prepolymer preferably used in the present invention is a polyester prepolymer (A) having an isocyanate group. The isocyanate group-containing polyester prepolymer (A) is produced by reacting a polyester having an active hydrogen group, which is a polycondensate of a polyol (PO) and a polycarboxylic acid (PC), with a polyisocyanate (PIC). . Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Of these, an alcoholic hydroxyl group is preferable.

Examples of the polyol include diol (DIO) and tri- or higher valent polyol (TO), and DIO alone or a mixture of DIO and a small amount of TO is preferable.
Examples of the diol include alkylene glycols (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycols (diethylene glycol, triethylene glycol, Dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.) An alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the alicyclic diol; Alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Of these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols, and alkylene glycols having 2 to 12 carbon atoms. Is a combination of
Examples of the trivalent or higher polyol include trihydric or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (trisphenol PA, Phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

Examples of the polycarboxylic acid (PC) include dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid (TC), and DIC alone or a mixture of DIC and a small amount of TC is preferable.
Dicarboxylic acids include alkylenedicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc.) ). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms.
Examples of the trivalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). As the polycarboxylic acid, the above-mentioned acid anhydride or lower alkyl ester (eg, methyl ester, ethyl ester, isopropyl ester) may be used to react with the polyol.

  Examples of the polyisocyanate (PIC) include aliphatic polyisocyanates (such as tetramethylene diisocyanate, hexamethylene diisocyanate, and 2,6-diisocyanatomethylcaproate); alicyclic polyisocyanates (such as isophorone diisocyanate and cyclohexylmethane diisocyanate); Aromatic diisocyanates (such as tolylene diisocyanate and diphenylmethane diisocyanate); araliphatic diisocyanates (such as α, α, α ′, α′-tetramethylxylylene diisocyanate); isocyanurates; Lactams and the like; and combinations of two or more of these.

  The ratio of the polyisocyanate is usually 5/1 to 1/1, preferably 4/1 to 1 as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the hydroxyl group-containing polyester. .2 / 1, more preferably 2.5 / 1 to 1.5 / 1. If [NCO] / [OH] exceeds 5, the low-temperature fixability deteriorates. If the molar ratio of [NCO] is less than 1, the urea content in the modified polyester becomes low, and the hot offset resistance deteriorates. The content of the polyisocyanate (PIC) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, and more preferably 2 to 20% by mass. It is. When the content is less than 0.5% by mass, the hot offset resistance is deteriorated, and the heat storage stability and the low-temperature fixability may be disadvantageous. On the other hand, if it exceeds 40% by mass, the low-temperature fixability may deteriorate.

The isocyanate group contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually at least 1, preferably 1.5 to 3 on average, and more preferably 1.8 to 2.5 on average. Individual. If the number is less than one per molecule, the molecular weight of the urea-modified polyester becomes low, and the hot offset resistance deteriorates.
The urea-modified polyester-based resin (UMPE) can be obtained from the polyester prepolymer (A) having an isocyanate group by reacting it with the amines (B). This shows an excellent effect as a toner binder.

  Examples of the amines (B) include diamine (B1), trivalent or higher polyamine (B2), amino alcohol (B3), aminomercaptan (B4), amino acid (B5), and amino group of (B1) to (B5). (B6). Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diamine Cyclohexane, isophoronediamine, etc.); and aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, etc.). Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of the amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of the aminomercaptan (B4) include aminoethylmercaptan and aminopropylmercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of (B6) in which the amino group of (B1) to (B5) is blocked include ketimine compounds obtained from amines and ketones (such as acetone, methyl ethyl ketone, and methyl isobutyl ketone) of (B1) to (B5); Oxazolidine compounds and the like. Preferred among these amines (B) are (B1) and a mixture of (B1) and a small amount of B2.

  Further, the molecular weight of a modified polyester such as a urea-modified polyester can be adjusted by using an elongation terminator, if necessary. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine and the like), and those obtained by blocking them (ketimine compounds).

The ratio of the amines (B) is defined as the equivalent ratio [NCO] / [NHx] of the isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and the amino groups [NHx] in the amines (B). , Usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, and more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the urea-modified polyester becomes low, and the hot offset resistance deteriorates. In the present invention, the polyester modified with a urea bond may contain a urethane bond together with the urea bond. The molar ratio of the urea bond content to the urethane bond content is usually from 100/0 to 10/90, preferably from 80/20 to 20/80, and more preferably from 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance deteriorates.
The amines (B) act as a crosslinking agent or an elongation agent for the modified polyester that can react with active hydrogen.

  The urea-modified polyester used in the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester such as the urea modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of a modified polyester such as a urea modified polyester is not particularly limited when an unmodified polyester described later is used, and may be a number average molecular weight that is easily obtained to obtain the weight average molecular weight. In the case of a modified polyester alone such as a urea-modified polyester, the number average molecular weight is usually 20,000 or less, preferably 1,000 to 10,000, and more preferably 2,000 to 8,000. If it exceeds 20,000, the low-temperature fixability and the gloss when used in a full-color device deteriorate.

-Unmodified polyester-
In the present invention, not only the modified polyester (MPE) such as the polyester modified by the urea bond may be used alone, but also an unmodified polyester (PE) may be contained as a toner binder component. The combined use of PE improves low-temperature fixability and glossiness when used in a full-color device, and is preferable to single use. Examples of the PE include polycondensates of a polyol and a polycarboxylic acid, which are the same as the polyester component of the MPE. The PE may be modified not only with unmodified polyester but also with a chemical bond other than a urea bond. For example, the PE may be modified with a urethane bond. It is preferable that at least a part of MPE and PE be compatible with each other in view of low-temperature fixability and hot offset resistance. Therefore, it is preferable that the polyester component of the MPE and the PE have similar compositions. When PE is contained, the weight ratio of MPE to PE is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, and particularly preferably 7/93. ２０20/80. When the mass ratio of the MPE is less than 5%, the hot offset resistance is deteriorated and the heat storage stability and the low-temperature fixability are disadvantageous.

The peak molecular weight of PE is generally from 1,000 to 30,000, preferably from 1500 to 10,000, and more preferably from 2,000 to 8,000. If it is less than 1,000, the heat-resistant storage stability deteriorates, if it exceeds 30,000, the low-temperature fixability deteriorates considerably, and if it exceeds 10,000, the low-temperature fixability slightly deteriorates. The hydroxyl value of PE is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of compatibility between heat-resistant storage stability and low-temperature fixability. The acid value of PE is usually 1 to 30, preferably 5 to 20. By having an acid value, it tends to be negatively chargeable.
The glass transition point of the unmodified polyester resin is preferably from 40 to 70C.

In the present invention, the glass transition point (Tg) of the binder (toner binder) in the toner is usually 50 to 70 ° C, preferably 55 to 65 ° C. If the temperature is lower than 50 ° C., the heat-resistant storage stability of the toner deteriorates. Due to the coexistence of a modified polyester such as a urea-modified polyester-based resin, the dry toner of the present invention tends to have good heat-resistant storage stability even at a low glass transition point, as compared with known polyester-based toners.
As for the storage elastic modulus of the toner binder, the temperature (TG ') at which the measurement frequency is 20 Hz becomes 10,000 dyne / cm ² is usually 100 ° C. or higher, preferably 110 to 200 ° C. If the temperature is lower than 100 ° C., the hot offset resistance deteriorates. As for the viscosity of the toner binder, the temperature (Tη) at which the viscosity becomes 1000 poise at a measurement frequency of 20 Hz is usually 180 ° C. or less, preferably 90 to 160 ° C. If it exceeds 180 ° C., the low-temperature fixability deteriorates. That is, TG ′ is preferably higher than Tη from the viewpoint of achieving both low-temperature fixability and hot offset resistance. In other words, the difference between TG ′ and Tη (TG′−Tη) is preferably 0 ° C. or more. It is more preferably at least 10 ° C, particularly preferably at least 20 ° C. The upper limit of the difference is not particularly limited. The difference between Tη and Tg is preferably from 0 to 100 ° C. from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability. The temperature is more preferably from 10 to 90 ° C, particularly preferably from 20 to 80 ° C.

-Colorant-
As the colorant used in the present invention, known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow oxide Iron, ocher, graphite, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine lake, Quinoline yellow lake, Anthrazan yellow BGL, Isoindolinone yellow, Bengala, Lead red, Lead red, Cadmium red, Cadmium mercury red, Antimony red, Permanent red 4R, Para Red, Phisa Red, Para Chlor Rutonitroaniline red, Risor fast scarlet G, brilliant fast scarlet, brilliant kahnmin BS, permanent red (F2R, F4R, FRL, FRLL, F4RH), fast scarlet VD, Belkan fast rubin B, brilliant scarlet G, risor rubin GX, permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlett 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Museum, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake , Thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazo Red, polyazo red, chrome vermillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue lake, peacock blue lake, Victoria blue lake, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue, indance Renblue (RS, BC), indigo, ultramarine, navy blue, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Le , Phthalocyanine green, anthraquinone green, titanium oxide, zinc white, lithobone and mixtures thereof can be used. The content of the colorant is usually from 1 to 15% by mass, and preferably from 3 to 10% by mass, based on the toner.

  The colorant used in the present invention can be used as a masterbatch combined with a resin. Examples of the binder resin to be manufactured or kneaded together with the master batch include, in addition to the above-mentioned modified and unmodified polyester resins, polystyrene, poly-p-chlorostyrene, polymers of styrene such as polyvinyltoluene and their substituted polymers. Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α -Chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. can be used alone or in combination. You.

  This masterbatch can be obtained by mixing and kneading the resin for the masterbatch and the colorant with high shearing force to obtain a masterbatch. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. The so-called flushing method is also known as a method of mixing and kneading an aqueous paste containing water of a coloring agent together with a resin and an organic solvent, transferring the coloring agent to the resin side, and removing water and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high-shear dispersion device such as a three-roll mill is preferably used.

-Release agent-
Known release agents can be used as the release agent used in the present invention. For example, polyolefin wax (polyethylene wax, polypropylene wax, etc.); long-chain hydrocarbon (paraffin wax, sasol wax, etc.); carbonyl group-containing wax, and the like. Preferred among these are carbonyl group-containing waxes. Examples of the carbonyl group-containing wax include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18 Polyalkanol esters (such as tristearyl trimellitate and distearyl maleate); polyalkanoic acid amides (such as ethylenediamine dibehenyl amide); polyalkylamides (such as trimellitic acid tristearyl amide) And dialkyl ketones (such as distearyl ketone). Preferred among these carbonyl group-containing waxes are polyalkanoic esters. The melting point of the wax of the present invention is usually 40 to 160 ° C, preferably 50 to 120 ° C, and more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat-resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause cold offset at the time of fixing at a low temperature. The melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps, as a value measured at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor improvement effects on hot offset resistance and low-temperature fixability. The content of the wax in the toner is usually from 0 to 40% by mass, and preferably from 3 to 30% by mass.

-Charge control agent-
The toner of the present invention may optionally contain a charge control agent. Known charge control agents can be used, for example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified Quaternary ammonium salts), alkyl amides, simple substances or compounds of phosphorus, tungsten simple substances or compounds, fluorinated activators, metal salts of salicylic acid, and metal salts of salicylic acid derivatives. Specifically, bontron 03 of a nigrosine dye, bontron P-51 of a quaternary ammonium salt, bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid-based metal complex, and E-82 of a salicylic acid-based metal complex 84, phenolic condensate E-89 (all manufactured by Orient Chemical Industry Co., Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (all manufactured by Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (all from Hoechst), LRA-901, LR-147 which is a boron complex (Manufactured by Nippon Carlit), copper phthalocyanine, perylene, quinacridone, Zone-based pigment, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  In the present invention, the amount of the charge control agent used is determined by the type of the binder resin, the presence or absence of additives used as necessary, the toner manufacturing method including the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the binder resin. Preferably, the range is 0.2 to 5 parts by mass. If the amount exceeds 10 parts by mass, the chargeability of the toner is too large, the effect of the main charge control agent is reduced, the electrostatic attraction force with the developing roller increases, the fluidity of the developer decreases, and the image density decreases. Causes a decline. These charge control agents can be dissolved and dispersed after being melt-kneaded with the masterbatch and the resin, or may be added when directly dissolving and dispersing in an organic solvent, or may be fixed after toner particles are formed on the toner surface. You may.

-External additives-
As the external additive for assisting the fluidity, developability and chargeability of the colored resin particles obtained in the present invention, inorganic fine particles can be preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 μm to 2 μm, and particularly preferably 5 μm to 500 μm. Further, the specific surface area by the BET method is preferably from 20 to 500 m ² / g. The use ratio of the inorganic fine particles is preferably from 0.01 to 5% by mass of the toner, and particularly preferably from 0.01 to 2.0% by mass. Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, and diatomaceous Examples include earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
In addition, polymer-based fine particles such as polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, polycondensation systems such as silicone, benzoguanamine, and nylon, and methacrylic acid ester and acrylic acid ester copolymers, and thermosetting resins Polymer particles.

Such an external additive can be subjected to a surface treatment to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate-based coupling agents, aluminum-based coupling agents, silicone oil, modified silicone oil, and the like are preferable surface treatment agents. .
Examples of the cleaning property improver for removing the developer after transfer remaining on the photoreceptor and the primary transfer medium include, for example, zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, for example, polymethyl methacrylate fine particles, polystyrene fine particles, and the like. And polymer fine particles produced by soap-free emulsion polymerization of the above. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

(Method for producing binder component)
The toner binder can be manufactured by the following method or the like. Polyols and polycarboxylic acids are heated to 150 to 280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate and dibutyltin oxide, and if necessary, the resulting water is distilled off while reducing the pressure, thereby obtaining a polyester having a hydroxyl group. Get. Next, at 40 to 140 ° C., a polyisocyanate is reacted therewith to obtain a prepolymer (A) having an isocyanate group. Further, this A is reacted with an amine (B) at 0 to 140 ° C. to obtain a polyester modified with a urea bond. When reacting the polyisocyanate and when reacting A and B, a solvent can be used if necessary. Examples of usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And the like (e.g., tetrahydrofuran), which are inert to polyisocyanates (PIC). When a polyester (PE) not modified with a urea bond is used in combination, this PE is produced in the same manner as in the case of the polyester having a hydroxyl group, and this PE is dissolved in a solution after the reaction of the urea-modified polyester, Mix.

(Manufacture of toner)
The dry toner of the present invention can be produced by the following method, but is not limited thereto.

(Method of manufacturing toner in aqueous medium)
As the aqueous medium, water alone may be used, or a water-miscible solvent may be used in combination. Examples of miscible solvents include alcohols (eg, methanol, isopropanol, ethylene glycol), dimethylformamide, tetrahydrofuran, cellosolves (eg, methylcellosolve), lower ketones (eg, acetone, methylethylketone), and the like.

  The toner particles can be formed by reacting a dispersion composed of a prepolymer (A) having an isocyanate group with an amine (B) in an aqueous medium. As a method for stably forming a dispersion comprising a urea-modified polyester or prepolymer (A) in an aqueous medium, a composition of a toner raw material comprising a urea-modified polyester or prepolymer (A) is added to an aqueous medium. And a method of dispersing into fine particles by a shearing force. The prepolymer (A) and other toner components (hereinafter sometimes referred to as toner raw materials) such as a colorant, a colorant masterbatch, a release agent, a charge control agent, and an unmodified polyester resin are contained in an aqueous medium. May be mixed when forming a dispersion, but it is more preferable to mix the toner raw materials in advance and then add and disperse the mixture in an aqueous medium. Further, in the present invention, other toner raw materials such as a coloring agent, a release agent, and a charge control agent do not necessarily have to be mixed when forming particles in an aqueous medium, and after the particles are formed. May be added. For example, after forming particles containing no coloring agent, a coloring agent can be added by a known dyeing method.

  The dispersing method is not particularly limited, but known equipment such as a low-speed shearing type, a high-speed shearing type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferred. When a high-speed shearing disperser is used, the number of revolutions is not particularly limited, but it is usually 1,000 to 30,000 rpm, preferably 5,000 to 20,000 rpm. The dispersion time is not particularly limited, but is usually 0.1 to 5 minutes in the case of a batch system. The temperature at the time of dispersion is usually 0 to 150 ° C (under pressure), preferably 40 to 98 ° C. Higher temperatures are preferred in that the dispersion of the urea-modified polyester or prepolymer (A) has a lower viscosity and is easier to disperse.

The amount of the aqueous medium to be used is usually 50 to 2,000 parts by mass, preferably 100 to 1,000 parts by mass, based on 100 parts of the toner component (composition) containing the urea-modified polyester and the prepolymer (A). If the amount is less than 50 parts by mass, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle size may not be obtained. If the amount exceeds 2,000 parts by mass, it is not economical. In addition, a dispersant can be used if necessary. The use of a dispersant is preferred because the particle size distribution becomes sharp and the dispersion is stable.
In the step of synthesizing the urea-modified polyester from the prepolymer (A), the amines (B) may be added and reacted before dispersing the toner components in the aqueous medium, or the amines may be dispersed after dispersing in the aqueous medium. The reaction may be caused from the particle interface by adding (B). In this case, urea-modified polyester is preferentially generated on the surface of the toner to be produced, and a concentration gradient can be provided inside the particles.

  An oily phase in which the toner component is dispersed is emulsified and dispersed in a liquid containing water, as a dispersant for alkylbenzene sulfonate, α-olefin sulfonate, anionic surfactant such as phosphate ester, Alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride Nonionic surfactants such as quaternary ammonium salt-type cationic surfactants such as fatty acid amide derivatives and polyhydric alcohol derivatives such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N- Al Le -N, amphoteric surfactants such as N- dimethyl ammonium betaine.

  Further, by using a surfactant having a fluoroalkyl group, the effect can be improved with a very small amount. Preferred examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkyl carboxylic acid having 2 to 10 carbon atoms and a metal salt thereof, disodium perfluorooctanesulfonylglutamate, and 3- [omega-fluoroalkyl (C6 to C11). ) Oxy] -1-alkyl (C3-C4) sulfonic acid sodium salt, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium salt, fluoroalkyl (C11-C20) carboxylic acid Acid and metal salt, perfluoroalkylcarboxylic acid (C7-C13) and its metal salt, perfluoroalkyl (C4-C12) sulfonic acid and its metal salt, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl) -Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.

  As trade names, Surflon S-111, S-112, S-113 (manufactured by Asahi Glass Co., Ltd.), Florad FC-93, FC-95, FC-98, FC-129 (manufactured by Sumitomo 3M), Unidyne DS-101 , DS-102, (manufactured by Taikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink), Ektop EF-102 , 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products Inc.), Futagent F-100, F150 (manufactured by Neos), and the like.

  Examples of the cationic surfactant include an aliphatic primary, secondary or secondary amino acid having a fluoroalkyl group, an aliphatic quaternary ammonium salt such as a perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, and benza. Ruconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names are Surflon S-121 (manufactured by Asahi Glass Co., Ltd.), Florad FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (manufactured by Daikin Industries, Ltd.) , Megafac F-150, F-824 (manufactured by Dainippon Ink and Chemicals), Ectop EF-132 (manufactured by Tochem Products), Futagent F-300 (manufactured by Neos) and the like.

Calcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like can also be used as inorganic compound dispersants which are hardly soluble in water.
Further, the dispersed droplets may be stabilized by a polymer-based protective colloid. For example, an acid such as acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride, or a (meth) acrylic monomer containing a hydroxyl group Such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylic acid Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerin monoacrylate, glycerin monomethacrylate, N- Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or esters of vinyl alcohol and a compound containing a carboxyl group, for example, acetic acid Pinyl, vinyl propionate, vinyl butyrate, etc., acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, pinyl pyridine, vinyl pyrrolidone, vinyl imidazole, ethylene imine Homopolymers or copolymers such as those having a nitrogen atom or a heterocycle thereof, polyoxyethylene, polyoxypropylene, Siethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester For example, celluloses such as polyoxyethylene, methylcellulose, hydroxyethylcellulose, and hydroxypropylcellulose can be used.

In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. I do. In addition, it can be removed by an operation such as decomposition with an enzyme.
When a dispersant is used, the dispersant may remain on the surface of the toner particles. However, it is preferable to remove the dispersant by washing after the elongation and / or cross-linking reaction from the charged surface of the toner.

  Further, in order to lower the viscosity of the liquid containing the toner component, a solvent in which the urea-modified polyester or the prepolymer (A) is soluble can be used. The use of a solvent is preferred in that the particle size distribution becomes sharp. It is preferable that the solvent is volatile having a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, Methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride are preferred. The amount of the solvent to be used relative to 100 parts by mass of the prepolymer (A) is usually 0 to 300 parts by mass, preferably 0 to 100 parts by mass, and more preferably 25 to 70 parts by mass. When a solvent is used, after the elongation and / or crosslinking reaction, the solvent is removed by heating under normal pressure or reduced pressure.

  When the modified polyester capable of reacting with active hydrogen is reacted with an amine (B) as a crosslinking agent and / or an elongating agent, the elongation and / or crosslinking reaction time depends on the isocyanate group structure of the prepolymer (A) and the amine. It is selected depending on the reactivity in combination with the class (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0-150C, preferably 40-98C. In addition, a known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

(Deformation process)
To obtain a non-spherical shape, an emulsified dispersion (oil phase) is mixed with a high-viscosity aqueous solution (aqueous phase) containing a thickener, an activator, etc. The emulsified particles can be deformed by utilizing the difference in viscosity between the oil phase and the aqueous phase by passing through a device that applies a shearing force such as a dough. As the conditions for deforming the shape, the viscosity difference between the oil phase and the aqueous phase is adjusted by adjusting the concentration and temperature of the hydrophilic organic solvent in the oil phase, the thickener and the activator in the aqueous phase, and the temperature. It can be adjusted by the method. As the hydrophilic organic solvent, conventionally known ones can be used, and ethyl acetate is particularly preferable. The measurement of the organic solvent concentration can also be controlled by a method for adjusting the shearing force of the apparatus, for example, the shape of the processing apparatus, the processing time, the number of times of processing, or the processing temperature.

  In order to remove the organic solvent from the obtained emulsified dispersion, a method of gradually raising the temperature of the entire system and completely evaporating and removing the organic solvent in the droplets can be adopted. Alternatively, it is also possible to spray the emulsified dispersion in a dry atmosphere, completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and collectively evaporate and remove the aqueous dispersant. . As a drying atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide, combustion gas, or the like, particularly various air streams heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. The desired quality can be sufficiently obtained by a short-time treatment such as a spray dryer, a belt dryer, and a rotary kiln.

The particle size distribution at the time of emulsification dispersion is wide, and when washing and drying are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classifying into a desired particle size distribution.
In the classification operation, the fine particle portion can be removed in the liquid by cyclone, decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder after drying, but it is preferable to perform the classification operation in a liquid in terms of efficiency. The obtained unnecessary fine particles or coarse particles can be returned to the kneading step again and used for forming particles. At this time, the fine particles or coarse particles may be in a wet state.
The dispersant used is preferably removed from the obtained dispersion as much as possible, but is preferably carried out simultaneously with the classification operation described above.
By mixing the resulting dried toner powder with different kinds of particles such as release agent fine particles, charge control fine particles, fluidizing agent fine particles, and colorant fine particles, or by applying a mechanical impact force to the mixed powder. Immobilization and fusion at the surface can prevent the dissociation of foreign particles from the surface of the resulting composite particles.

  As a specific means, a method of applying an impact force to the mixture by a high-speed rotating blade, a method of throwing the mixture into a high-speed air stream, accelerating, and causing the particles or composite particles to collide with an appropriate collision plate, and the like. is there. As the equipment, Angular Mill (manufactured by Hosokawa Micron), I-type mill (manufactured by Nippon Pneumatic) was modified to reduce the pulverizing air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), Kryptron system (Made by Kawasaki Heavy Industries, Ltd.), automatic mortar, and the like.

(Carrier for two components)
When the toner of the present invention is used in a two-component developer, the toner may be mixed with a magnetic carrier. Parts are preferred. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, and magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. In addition, polyvinyl and polyvinylidene resins, for example, acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins such as polystyrene resins and styrene acrylic copolymer resins, polychlorinated resins Halogenated olefin resin such as vinyl, polyester resin such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resin, polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Monomers including a fluoro terpolymers such, and silicone resins. If necessary, a conductive powder or the like may be contained in the coating resin. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide and the like can be used. These conductive powders preferably have an average particle size of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control the electric resistance.
Further, the toner of the present invention can be used as a one-component magnetic toner or a non-magnetic toner without using a carrier.

  The process cartridge of the present invention uses the toner of the present invention, integrally supports a photosensitive member and at least one unit selected from a charging unit, a developing unit, and a cleaning unit, and is detachable from the image forming apparatus main body. It is a cartridge.

FIG. 4 shows a schematic configuration of an image forming apparatus having the process cartridge of the present invention.
In the figure, (20) shows the whole process cartridge, (21) shows a photoreceptor, (22) shows a charging means, (23) shows a developing means, and (24) shows a cleaning means.
In the present invention, a plurality of components such as the photoreceptor (21), the charging unit (22), the developing unit (23), and the cleaning unit (24) are integrally combined as a process cartridge. The process cartridge is configured to be detachable from an image forming apparatus main body such as a copying machine or a printer.

  In the image forming apparatus having the process cartridge of the present invention, the photosensitive member is driven to rotate at a predetermined peripheral speed. In the rotation process, the photoreceptor receives a uniform charge of a predetermined positive or negative potential on its peripheral surface by the charging means, and then receives image exposure light from image exposure means such as slit exposure or laser beam scanning exposure, and thus the photosensitive element is exposed. An electrostatic latent image is sequentially formed on the peripheral surface of the body, and the formed electrostatic latent image is then subjected to toner development by a developing unit. The developed toner image is transferred between a photoreceptor and a transfer unit from a paper feeding unit. The recording medium is sequentially transferred to a transfer material fed in synchronization with the rotation of the photoconductor. The transfer material having undergone the image transfer is separated from the surface of the photoreceptor, introduced into an image fixing unit, where the image is fixed, and printed out of the apparatus as a copy. The surface of the photoreceptor after the image transfer is cleaned to remove the untransferred toner by a cleaning unit, is cleaned, and is further subjected to charge elimination.

An image forming apparatus according to the present invention is an image forming apparatus, wherein a photosensitive member used for forming an image is an amorphous silicon photosensitive member.
-Amorphous silicon photoreceptor-
As the electrophotographic photoreceptor used in the present invention, a conductive support is heated to 50 ° C. to 400 ° C., and a vacuum deposition method, a sputtering method, an ion plating method, a thermal CVD method, and a photo CVD method are formed on the support. An amorphous silicon photosensitive member having a photoconductive layer made of a-Si (hereinafter, may be referred to as an “a-Si photosensitive member”) by a film forming method such as a plasma CVD method or the like can be used. Among them, a plasma CVD method, that is, a method in which a raw material gas is decomposed by direct current, high frequency, or microwave glow discharge to form an a-Si deposited film on a support is used as a suitable method.

-Layer configuration-
The layer configuration of the amorphous silicon photoconductor is, for example, as follows. FIG. 5 is a schematic configuration diagram for explaining a layer configuration. The electrophotographic photoconductor (500) shown in FIG. 5A has a photoconductive layer (502) made of a-Si: H, X and having photoconductivity provided on a support (501). . An electrophotographic photoreceptor (500) shown in FIG. 5 (b) comprises a photoconductive layer (502) made of a-Si: H, X and having photoconductivity and an amorphous silicon on a support (501). And a system surface layer (503). An electrophotographic photoreceptor (500) shown in FIG. 5C includes a photoconductive layer (502) made of a-Si: H, X and having photoconductivity, and an amorphous silicon film formed on a support (501). It comprises a system surface layer (503) and an amorphous silicon-based charge injection blocking layer (504). An electrophotographic photoconductor (500) shown in FIG. 5D has a photoconductive layer (502) provided on a support (501). The photoconductive layer (502) is composed of a charge generation layer (505) made of a-Si: H, X and a charge transport layer (506), on which an amorphous silicon-based surface layer (503) is provided. .

-Support-
The support for the photoreceptor may be conductive or electrically insulating. Examples of the conductive support include metals such as Al, Cr, Mo, Au, In, Nb, Te, V, Ti, Pt, Pd, and Fe, and alloys thereof, such as stainless steel. Further, a film or sheet of a synthetic resin such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, polyamide, etc., at least the surface on the side on which the photosensitive layer is formed of an electrically insulating support such as glass, ceramic, etc. A support subjected to a conductive treatment can also be used.

  The shape of the support may be a cylindrical surface or a plate shape having a smooth surface or an uneven surface, or an endless belt shape, and the thickness thereof is appropriately determined so as to form a desired photoreceptor for an image forming apparatus. When the photoreceptor for an image forming apparatus is required to have flexibility, the photoreceptor can be made as thin as possible within a range where the function as a support can be sufficiently exhibited. However, the thickness of the support is usually 10 μm or more in terms of production, handling, mechanical strength and the like.

-Injection prevention layer-
The amorphous silicon photoreceptor that can be used in the present invention has a charge injection blocking layer that functions to prevent charge injection from the conductive support side between the conductive support and the photoconductive layer as necessary. It is more effective to provide them (see FIG. 5C). That is, the charge injection blocking layer has a function of preventing charges from being injected from the support side to the photoconductive layer side when the photosensitive layer has been subjected to a charging treatment of a fixed polarity on its free surface. It has a so-called polarity dependency in which such a function is not exhibited when subjected to a charging treatment. In order to provide such a function, the charge injection blocking layer contains a relatively large number of atoms for controlling conductivity as compared with the photoconductive layer.
The thickness of the charge injection blocking layer is preferably from 0.1 to 5 μm, more preferably from 0.3 to 4 μm, and most preferably from 0.5 to 5 μm, from the viewpoint of obtaining desired electrophotographic characteristics and economic effects. It is desirable that the thickness be 3 μm.

-Photoconductive layer-
The photoconductive layer is formed on the undercoat layer as needed, and the layer thickness of the photoconductive layer is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economical effects. The thickness is desirably about 100 μm, more preferably about 20 μm to about 50 μm, and most preferably about 23 μm to about 45 μm.

-Charge transport layer-
The charge transport layer is a layer mainly having a function of transporting charge when the photoconductive layer is functionally separated. This charge transport layer is composed of a-SiC (H, F, O) containing at least silicon atoms, carbon atoms, and fluorine atoms as its constituent elements, and if necessary, containing hydrogen atoms and oxygen atoms. It has conductive properties, especially charge retention properties, charge generation properties and charge transport properties. In the present invention, it is particularly preferable to contain an oxygen atom.
The thickness of the charge transport layer is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic properties and economic effects. For the charge transport layer, preferably 5 to 50 μm, more preferably 10 to 40 μm, Most preferably, it is 20 to 30 μm.

-Charge generation layer-
The charge generation layer is a layer mainly having a function of generating charge when the photoconductive layer is separated in function. The charge generation layer is composed of a-Si: H containing at least silicon atoms as constituent elements, substantially containing no carbon atoms and, if necessary, containing hydrogen atoms, and has desired photoconductive properties, particularly charge generation properties. And has charge transport properties.
The thickness of the charge generation layer is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, and is preferably 0.5 to 15 μm, more preferably 1 to 10 μm, and most preferably 1 to 10 μm. ５5 μm.

-Surface layer-
In the amorphous silicon photoreceptor that can be used in the present invention, if necessary, a surface layer can be further provided on the photoconductive layer formed on the support as described above. It is preferable to form a surface layer. This surface layer has a free surface and is provided mainly to achieve the object of the present invention in terms of moisture resistance, continuous repeated use characteristics, electric pressure resistance, use environment characteristics, and durability.
The layer thickness of the surface layer in the present invention is desirably usually 0.01 to 3 μm, preferably 0.05 to 2 μm, and most preferably 0.1 to 1 μm. If the thickness is less than 0.01 μm, the surface layer is lost due to abrasion or the like during use of the photoreceptor, and if it exceeds 3 μm, the electrophotographic characteristics such as an increase in residual potential are observed.

An image forming apparatus according to the present invention is an image forming apparatus wherein an alternating electric field is applied when developing a latent image on a photoconductor.
In the developing device (620) of this embodiment shown in FIG. 6, at the time of development, an oscillating bias voltage in which an AC voltage is superimposed on a DC voltage is applied to the developing sleeve (621) as a developing bias by a power source (622). You. The background portion potential and the image portion potential are located between the maximum value and the minimum value of the vibration bias potential. As a result, an alternating electric field whose direction changes alternately is formed in the developing section (623). In this alternating electric field, the toner and carrier of the developer vibrate violently, and the toner flies over the photosensitive drum (624) by shaking off the electrostatic restraining force on the developing sleeve (621) and the carrier, and the latent on the photosensitive drum (624). It adheres to the image.

  The difference (peak-to-peak voltage) between the maximum value and the minimum value of the vibration bias voltage is preferably 0.5 to 5 KV, and the frequency is preferably 1 to 10 KHz. As the waveform of the oscillation bias voltage, a rectangular wave, a sine wave, a triangular wave, or the like can be used. As described above, the DC voltage component of the vibration bias is a value between the background portion potential and the image portion potential. However, a value closer to the background portion potential than the image portion potential is more likely to cover the background portion potential region. It is preferable for preventing the adhesion of the toner.

  When the waveform of the oscillation bias voltage is a rectangular wave, the duty ratio is desirably set to 50% or less. Here, the duty ratio is a ratio of a time during which the toner goes to the photoconductor during one cycle of the vibration bias. By doing so, the difference between the peak value of the toner going to the photoreceptor and the time average value of the bias can be increased, so that the movement of the toner is further activated, and the potential of the toner on the latent image surface is increased. It adheres faithfully to the distribution and can improve roughness and resolution. Also, since the difference between the peak value of the carrier having the opposite polarity to the toner and the time average value of the bias toward the photoreceptor can be reduced, the motion of the carrier is calmed down, and the background portion of the latent image is reduced. Can significantly reduce the probability that carriers will adhere to the substrate.

The image forming apparatus according to the present invention is an image forming apparatus, wherein the charging device is a charging device that contacts a charging member to a latent image carrier and applies a voltage to the charging member to perform charging. .
-Roller charging-
FIG. 8A shows a schematic configuration of an example of an image forming apparatus using a contact-type charging device. The photoreceptor as an object to be charged and an image carrier is driven to rotate at a predetermined speed (process speed) in the direction of the arrow. The charging roller, which is a charging member brought into contact with the photosensitive drum, basically includes a core metal and a conductive rubber layer formed on the roller concentrically around the core metal, and both ends of the core metal are bearing members (not shown). And the photosensitive drum is pressed against the photosensitive drum by a predetermined pressing force by a pressing means (not shown). In the case of this figure, the charging roller rotates following the rotation of the photosensitive drum. . The charging roller is formed to a diameter of 16 mm by coating a medium resistance rubber layer of about 100,000 Ω · cm on a core metal having a diameter of 9 mm.

  The core of the charging roller is electrically connected to a power supply shown in the figure, and a predetermined bias is applied to the charging roller by the power supply. As a result, the peripheral surface of the photoconductor is uniformly charged to a predetermined polarity and potential.

  The shape of the charging member used in the present invention may be any form such as a magnetic brush and a fur brush other than the roller, and can be selected according to the specification and form of the electrophotographic apparatus. When using a magnetic brush, the magnetic brush uses various ferrite particles such as Zn-Cu ferrite as a charging member, and is configured by a non-magnetic conductive sleeve for supporting the ferrite particles, and a magnet roll included therein. Or, when using a brush, for example, fur fur is conductively treated with carbon, copper sulfide, metal, and metal oxide as the material of the fur brush, and is wrapped or attached to a metal or other conductive treated metal core. To make a charger.

-In case of fur brush charging-
FIG. 8B shows a schematic configuration of an example of an image forming apparatus using a contact-type charging device. The photoreceptor as an object to be charged and an image carrier is driven to rotate at a predetermined speed (process speed) in the direction of the arrow. A brush roller constituted by a fur brush is brought into contact with the photosensitive member at a predetermined nip width with a predetermined pressing force against the elasticity of the brush portion.

  The fur brush roller as the contact charging member in the present example is a spiral made of a tape in which a conductive rayon fiber REC-B manufactured by Unitika Ltd. is piled as a brush on a metal core having a diameter of 6 mm also serving as an electrode. And rolled into a roll brush having an outer diameter of 14 mm and a longitudinal length of 250 mm. The brushes in the brush section have a density of 300 denier / 50 filaments, 155 per square millimeter. The roll brush was inserted into a pipe having an inner diameter of 12 mm while being rotated in one direction, the brush and the pipe were set to be concentric, and the brush and the pipe were left in a high-temperature and high-humidity atmosphere so that the hair was slanted with a habit.

The resistance value of the fur brush roller is 1 × 10 ⁵ Ω at an applied voltage of 100 V. The resistance value was calculated from the current flowing when a fur brush roller was brought into contact with a metal drum having a diameter of φ30 mm with a nip width of 3 mm and a voltage of 100 V was applied.
The resistance value of the fur brush charger is such that even if a low-voltage defect portion such as a pinhole occurs on the photoreceptor to be charged, an excessive leak current flows into this portion and the charging nip portion becomes poorly charged. It is required to be 10 ⁴ Ω or more in order to prevent image defects, and it is necessary to be 10 ⁷ Ω or less in order to sufficiently inject electric charge into the surface of the photoreceptor.

  In addition to REC-B manufactured by Unitika Ltd., REC-C, REC-M1, REC-M10, and furthermore, SA-7 manufactured by Toray Industries, Inc. Sanderon manufactured by Kanebo Co., Ltd., Bertron manufactured by Kuraray Co., Ltd., Cracarbo manufactured by Kuraray Co., Ltd., a material obtained by dispersing carbon in rayon, and Robal manufactured by Mitsubishi Rayon Co., Ltd. are conceivable. The brush preferably has a denier of 3 to 10 deniers, a density of 10 to 100 filaments / bundle, and a density of 80 to 600 brushes / mm. The hair foot is preferably 1 to 10 mm.

  The fur brush roller is rotationally driven at a predetermined peripheral speed (surface speed) in a direction (counter) opposite to the rotation direction of the photoconductor, and contacts the photoconductor surface with a speed difference. When a predetermined charging voltage is applied to the fur brush roller from a power supply, the surface of the rotating photoconductor is uniformly contact-charged to a predetermined polarity and potential. In this embodiment, the contact charging of the photoreceptor by the fur brush roller is performed by dominant direct injection charging, and the surface of the rotating photoreceptor is charged to a potential substantially equal to the charging voltage applied to the fur brush roller.

The charging member used in the present invention may take any form such as a charging roller and a fur brush, in addition to the fur brush roller, and can be selected according to the specifications and forms of the electrophotographic apparatus. When a charging roller is used, it is common to use a medium resistance rubber layer of about 100,000 Ω · cm on a cored bar. When using a magnetic brush, the magnetic brush uses various ferrite particles such as Zn-Cu ferrite as a charging member, and is configured by a non-magnetic conductive sleeve for supporting the ferrite particles, and a magnet roll included therein.
FIG. 7 is a diagram illustrating charging characteristics of contact charging.

-In case of magnetic brush charging-
FIG. 8B shows a schematic configuration of an example of an image forming apparatus using a contact-type charging device. The photoreceptor as an object to be charged and an image carrier is driven to rotate at a predetermined speed (process speed) in the direction of the arrow. A brush roller constituted by a magnetic brush is brought into contact with the photosensitive member at a predetermined nip width with a predetermined pressing force against the elasticity of the brush portion.

  As a magnetic brush as a contact charging member in the present example, Zn-Cu ferrite particles having an average particle size of 25 μm and Zn-Cu ferrite particles having an average particle size of 10 μm were mixed at a weight ratio of 1: 0.05. Magnetic particles were used in which ferrite particles having an average particle diameter of 25 μm and having a peak at each average particle diameter position were coated with a medium-resistance resin layer. The contact charging member is constituted by the coated magnetic particles prepared as described above, and a non-magnetic conductive sleeve for supporting the coated magnetic particles, and a magnet roll included in the sleeve. Coating was performed at 1 mm to form a charging nip having a width of about 5 mm between the photosensitive member and the photosensitive member. The gap between the magnetic particle holding sleeve and the photoconductor was about 500 μm. Further, the magnet roll is rotated so that the surface of the sleeve rubs in the opposite direction at twice the speed of the peripheral speed of the surface of the photoconductor, so that the photoconductor and the magnetic brush come into uniform contact. I did it.

  The shape of the charging member used in the present invention may be any shape such as a charging roller and a fur brush in addition to the magnetic brush, and can be selected according to the specifications and the shape of the electrophotographic apparatus. When a charging roller is used, it is common to use a medium resistance rubber layer of about 100,000 Ω · cm on a cored bar. Or, when using a brush, for example, fur fur is conductively treated with carbon, copper sulfide, metal, and metal oxide as the material of the fur brush, and is wrapped or attached to a metal or other conductive treated metal core. To make a charger.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to these examples. Hereinafter, “parts” indicates “parts by mass”.
Table 1 shows the toners used in the examples.

<Example 1>
(Synthesis of organic fine particle emulsion)
Production Example 1
In a reaction vessel equipped with a stirring rod and a thermometer, 754 parts of water, 13 parts of sodium salt of methacrylic acid ethylene oxide adduct sulfate (Eleminor RS-30, manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, 110 parts of butyl acrylate and 1 part of ammonium persulfate were charged and stirred at 400 rpm for 15 minutes to obtain a white emulsion. The mixture was heated to a temperature in the system of 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% aqueous solution of ammonium persulfate was added, and the mixture was aged at 75 ° C. for 5 hours. A dispersion liquid [polymer fine particle dispersion liquid 1] was obtained. The volume average particle diameter of [fine particle dispersion 1] measured with LA-920 was 0.10 μm. A part of [fine particle dispersion 1] was dried to isolate a resin component. The Tg of the resin component was 57 ° C.

(Preparation of aqueous phase)
Production Example 2
990 parts of water, 80 parts of [Particle Dispersion 1], 40 parts of a 48.5% aqueous solution of sodium dodecyldiphenyletherdisulfonate (Eleminol MON-7) (manufactured by Sanyo Chemical Industries), and 90 parts of ethyl acetate are mixed and stirred, and milky white is stirred. A liquid was obtained. This is designated as [aqueous phase 1].

(Unmodified polyester)
Production Example 3
570 parts of bisphenol A ethylene oxide 2 mol adduct, 217 parts of terephthalic acid, and 2 parts of dibutyltin oxide were added to a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and polycondensed at 230 ° C. for 8 hours under normal pressure. . Next, the mixture was cooled to 110 ° C. where the reaction was carried out at a reduced pressure of 10 to 15 mmHg for 5 hours, and 18 parts of trimellitic anhydride was added thereto and reacted for 2 hours to obtain an unmodified polyester (a).

(Example of prepolymer production)
Production Example 4
343 parts of bisphenol A ethylene oxide 2 mol adduct, 100 parts of isophthalic acid, 66 parts of terephthalic acid, and 2 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe. After reacting for 8 hours at a temperature of 10 ° C. and further dehydrating at a reduced pressure of 10 to 15 mmHg for 5 hours, the mixture was cooled to 110 ° C., and 32 parts of trimellitic anhydride was added thereto and reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 17 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate group-containing prepolymer (1).

(Production example of ketimine compound)
Production Example 5
170 parts of isophoronediamine and 70 parts of methyl ethyl ketone were charged into a reaction vessel equipped with a stirring rod and a thermometer, and reacted at 50 ° C. for 5 hours to obtain a ketimine compound (1).

(Example of toner production)
Production Example 6
In a beaker, 14.3 parts of the above prepolymer (1), 55 parts of unmodified polyester (a), and 78.6 parts of ethyl acetate were stirred and dissolved. Then, 10 parts of rice wax (melting point: 83 ° C.) as a release agent and 7 parts of carbon black # 44 (manufactured by Mitsubishi Chemical) were added, and the mixture was stirred at 60 ° C. with a TK type homomixer at 12,000 rpm for 5 minutes, and then mixed with a bead mill. Dispersed at 20 ° C. for 30 minutes. This is designated as a toner material solution (1).

  Next, the aqueous phase 1 liquid 306 parts container described above was weighed in a beaker. Next, while stirring at 12,000 rpm with a TK homomixer, the entire amount of the toner material solution (1) obtained by the above operation and 2.7 parts of the ketimine compound (1) were added to cause a urea reaction. When the particle size is large while observing the particle size and the particle size distribution with an optical microscope, the number of rotations for stirring is increased to 14000, and the process is further performed for 5 minutes. If smaller, change the stirring to 10,000 rpm and repeat the experiment. Next, the mixed solution was transferred to a kolben equipped with a thermometer equipped with a paddle-type stirring rod capable of a peripheral speed of 5 m / s or more, heated to 45 ° C., and stirred for 2 hours at a peripheral speed of 6 m / s. To obtain spindle-shaped base toner particles. During the stirring, a starch solution is added to control the viscosity of the aqueous phase to 1000 to 5000 CP. If the spindle type is insufficient, extend the stirring time. Thereafter, the solvent was removed under reduced pressure at 50 ° C. or lower for 1.0 hour, filtered, washed and dried, and then subjected to air classification to obtain spindle-shaped base particles.

Next, 100 parts of the obtained base particles and 0.25 part of a charge controlling agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were charged into a Q-type mixer (manufactured by Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine blade was set to 50 m / m. The operation time was set to sec, the operation was performed for 2 minutes, and the pause for 1 minute was performed 5 cycles, and the total processing time was set to 10 minutes.
Further, 0.5 parts of hydrophobic silica (H2000, manufactured by Clariant Japan Co., Ltd.) was added, the peripheral speed was set to 15 m / sec, and mixing was continued for 30 seconds for 1 minute, followed by 5 cycles to obtain a cyan toner. Next, 0.5 parts of hydrophobic silica and 0.5 parts of hydrophobic titanium oxide were mixed with a Henschel mixer to obtain a toner (1) of the present invention. Tables 2 and 3 show the evaluation results.

<Example 2>
(Example of prepolymer production)
Production Example 7
856 parts of bisphenol A ethylene oxide 2 mol adduct, 200 parts of isophthalic acid, 20 parts of terephthalic acid, and 4 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe. After reacting for 6 hours at 50 ° C and dehydrating under reduced pressure of 50 to 100 mmHg for 5 hours, the mixture was cooled to 160 ° C, and 18 parts of trimellitic anhydride was added thereto and reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 17 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate group-containing prepolymer (2).

(Example of toner production)
Production Example 8
In a beaker, 15.4 parts of the above prepolymer (2), 50 parts of unmodified polyester (a), and 95.2 parts of ethyl acetate were stirred and dissolved. Next, 20 parts of carnauba wax (molecular weight: 1800, acid value: 2.5, needle penetration: 1.5 mm / 40 ° C.), 7 parts of carbon black were added, and the mixture was stirred at 85 ° C. with a TK homomixer at 10,000 rpm, Dispersion, emulsification, and stirring were performed in the same manner as in Example 1 using a bead mill to obtain base toner particles (2). Tables 2 and 3 show the evaluation results.
Next, a toner (2) was produced in the same manner as in Example 1 except that the above-mentioned base particles and a charge control agent (Bontron E-89, manufactured by Orient Chemical Co., Ltd.) were used.

<Example 3>
(Example of production of unmodified polyester)
Production Example 9
589 parts of bisphenol A ethylene oxide 2 mol adduct, 464 parts of terephthalic acid dimethyl ester and 3 parts of dibutyltin oxide are added in the same manner as above, and polycondensation is carried out at 230 ° C. for 6 hours under normal pressure. After reacting for an hour, an unmodified polyester (b) was obtained.

(Example of toner production)
Production Example 10
In a beaker, 15.3 parts of the prepolymer (1), 63.6 parts of the unmodified polyester (b), 40 parts of toluene, and 40 parts of ethyl acetate were stirred and dissolved. Next, 10 parts of rice wax and 7 parts of carbon black (Regal 400R: manufactured by Cabot) were added, and the mixture was stirred at 60 ° C. with a TK homomixer at 12,000 rpm, and then dispersed at 25 ° C. for 30 minutes using a bead mill. Finally, 1.1 parts of diphenylmethane diisocyanate was added and dissolved as an extender. This is designated as a toner material solution (3).
The same operation as in Example 1 was carried out, and the toner material solution (3) was charged and stirred for 10 minutes while stirring at 12,000 rpm with a TK homomixer. Next, the mixed solution was transferred to a kolben equipped with a thermometer equipped with a paddle-type stirring bar and heated to 50 ° C. in 30 minutes to cause a urethane-forming reaction. Thereafter, the dispersion was homomixed (manufactured by Tokushu Kika) After stirring at a peripheral speed of 20.5 m / s for 25 minutes, the solvent was removed at 50 ° C. or lower, followed by filtration, washing and drying, followed by air classification to obtain spindle-shaped base particles of the present invention. Toner 3 was obtained in the same manner as in Example 1. Tables 2 and 3 show the evaluation results.

<Example 4>
(Example of prepolymer production)
Production Example 11
755 parts of bisphenol A ethylene oxide 2 mol adduct, 195 parts of isophthalic acid, 15 parts of terephthalic acid, and 4 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introducing pipe. After reacting for 8 hours at 50 ° C. and further dehydrating at 50 to 100 mmHg under reduced pressure for 5 hours, the mixture was cooled to 110 ° C., and 10 parts of trimetic anhydride was added thereto and reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 170 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate group-containing prepolymer (3).

(Example of toner production)
Production Example 12
15.4 parts of the prepolymer (3), 50 parts of unmodified polyester (a), and 95.2 parts of ethyl acetate were placed in a beaker, and stirred to dissolve. Next, 20 parts of carnauba wax (molecular weight: 1800, acid value: 2.5, needle penetration: 1.5 mm / 40 ° C) and 7 parts of carbon black (Mogal L: manufactured by Cabot) are added, and a TK homomixer is set at 85 ° C. Then, the mixture was stirred at 12,000 rpm to dissolve uniformly, and then dispersed in a bead mill at 15 ° C. for 50 minutes. This is designated as a toner material solution (4).
The toner material solution (4) was charged into the beaker while stirring at 12,000 rpm with a TK homomixer as in Example 1, and the mixture was stirred for 10 minutes. Then, 2.7 parts of the ketimine compound (1) was added to cause an extension reaction. Next, this mixed solution was transferred to a kolben equipped with a stirring rod and a thermometer, and stirred at 40 rpm at 300 rpm for 2 hours to produce spindle-shaped base toner particles. Thereafter, the solvent was removed at 40 ° C. for 1 hour, filtered, washed, and dried to obtain spindle-shaped base particles (4). At this time, the concentration of the emulsified dispersion was 13%. Toner 4 was obtained in the same manner as in Example 1. The results are shown in Tables 2 and 3.

<Comparative Example 1>
(Synthesis of toner binder)
395 parts of bisphenol A ethylene oxide 2 mol adduct and 166 parts of isophthalic acid were polycondensed using 2 parts of dibutyltin oxide as a catalyst to obtain a comparative toner binder (Comparative 1).

(Create toner)
In a beaker, 100 parts of the comparative toner binder (Comparative 1), 180 parts of ethyl acetate solution, 4 parts of copper phthalocyanine blue pigment, 10% liquid hydroxyapatite as a dispersant (Super Tight 10 manufactured by Nippon Chemical Industry Co., Ltd.) and dodecyl Sodium benzenesulfonate was added, and the mixture was stirred at 10000 rpm with a TK homomixer at 50 ° C. to be uniformly dissolved and dispersed. Next, a toner was formed in the same manner as in Example 1, but the solvent was removed in one hour in the solvent removing step. To 100 parts of the toner particles, 0.3 part of hydrophobic silica and 0.3 part of hydrophobic titanium oxide were mixed with a Henschel mixer.
Tables 2 and 3 show the evaluation results of the obtained toner.

<Comparative Example 2>
(Synthesis of toner binder)
343 parts of bisphenol A ethylene oxide 2 mol adduct, 166 parts of isophthalic acid, and 2 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 230 ° C. for 8 hours under normal pressure. After further reacting at a reduced pressure of 10 to 15 mmHg for 5 hours, the mixture was cooled to 80 ° C, 14 parts of toluene diisocyanate was added in toluene, and the reaction was carried out at 110 ° C for 5 hours, and then the solvent was removed to obtain a urethane-modified polyester. Was. 363 parts of bisphenol A ethylene oxide 2 mol adduct and 166 parts of isophthalic acid were polycondensed in the same manner as in Example 1 to obtain an unmodified polyester. 350 parts of the urethane-modified polyester and 650 parts of the unmodified polyester were dissolved and mixed in toluene, and then the solvent was removed to obtain a comparative toner binder (Comparative 2).

(Create toner)
100 parts of a comparative toner binder (2), 2 parts of a chromium salicylate complex (E-81 manufactured by Orient Chemical Co., Ltd.) as a charge control agent, and 4 parts of a copper phthalocyanine blue pigment were formed into a toner by the following method. First, the mixture was premixed using a Henschel mixer, and then kneaded with a continuous kneader. Next, after finely pulverizing with a jet pulverizer, the mixture was classified with an airflow classifier. To 100 parts of the toner particles, 0.3 part of hydrophobic silica and 0.3 part of hydrophobic titanium oxide were mixed with a Henschel mixer. Tables 2 and 3 show the evaluation results of the obtained toner.

<Comparative Example 3>
90 parts of polyester resin (bisphenol resin, manufactured by Kao Corporation) (Mn = 6000, Mw = 70000, Tg = 64 ° C.)
Carbon black (BP1300, manufactured by Cabot Corporation) 10 parts Rice wax (melting point 82 ° C.) 10 parts Diethyl ether / dichloromethane mixed solution (50:50) 300 parts

  The above components were mixed and dispersed by a ball mill for 10 hours. The obtained dispersion was put into 400 parts of a 2% aqueous solution of gum arabic, and subjected to a dispersion treatment for 3 minutes by a homomixer. Thereafter, the mixture was put into 2000 parts of pure water, kept at 80 ° C. in a water bath, and kept for 4 hours while stirring with a three-one motor. Thereby, irregularly shaped irregular particles having concave portions having an average particle diameter of 6.0 μm were obtained. The temperature of the suspension in this state was raised to 98 ° C., and maintained at that temperature for 1 hour to form a sphere with substantially the same particle diameter, and a charge control agent was added by the Q mixer in the same manner as in Example 1 to obtain Comparative Toner 3 Got. Tables 2 and 3 show the evaluation results.

<Comparative Example 4>
[Mixing process]
90 parts of styrene-n-butyl acrylate resin (copolymerization ratio 55:45, Mn = 3100, Mw = 8200, produced by solution polymerization)
Carbon black (manufactured by Cabot) 5 parts Polypropylene (molecular weight: about 8000, manufactured by Mitsui Petrochemical Company) 5 parts The above components were kneaded with a Banbury mixer (manufactured by Kobe Steel) to form a dispersion. 100 parts of this dispersion was put into 400 parts of ethyl acetate and stirred at 20 ° C. for 2 hours to obtain 500 parts of a toner compound mixed solution in which a styrene-n-butyl acrylate resin was dissolved.

[Dispersion suspension step]
Resin fine particles 22 parts (copolymer of sodium salt of styrene-methacrylic acid-butyl acrylate-ethylene methacrylate ethylene oxide adduct sulfate, 0.10 μm, Tg 57 ° C.)
Carboxymethylcellulose 0.03 parts (degree of etherification 0.75, average degree of polymerization 850, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
99.97 parts of ion-exchanged water The above components were introduced into an ultrasonic dispersing machine, and the resulting solution was stirred to form a solution as an aqueous medium. While stirring 220 g of the obtained aqueous medium with a homogenizer (manufactured by IKA) at 10,000 rpm, 100 g of the above-mentioned mixed solution of the toner mixture is slowly charged, and then stirred for 2 minutes to stop, and 320 g of the dispersion suspension solution is stirred. Got.

[Solvent Removal Step] The dispersion suspension produced in the dispersion suspension step was heated to 50 ° C. while stirring. The temperature was kept at 50 ° C. for 3 hours and then cooled to room temperature.
[Washing and Dehydration Step] To 200 g of the fine particle suspension obtained in the solvent removal step, 40 g of 10N hydrochloric acid was added, and the washing was repeated four times by suction filtration using ion-exchanged water.
[Drying and Sieving Step] The fine-particle cake obtained in the dehydration step was dried with a vacuum drier and sieved with a 45 μm mesh.
[External additive mixing step] The same operation as in Example 1 was performed.

<Comparative Example 5>
A part of the conditions of Production Example 6 was changed to produce a toner of Comparative Example 5.
In a beaker, 14.3 parts of the above prepolymer (1), 55 parts of unmodified polyester (a), and 78.6 parts of ethyl acetate were stirred and dissolved. Next, 10 parts of rice wax (melting point: 83 ° C.) as a release agent and 7 parts of carbon black # 44 (manufactured by Mitsubishi Chemical) were added, and the mixture was stirred at 60 ° C. with a TK homomixer at 12,000 rpm for 5 minutes, and then mixed with a bead mill at 30 ° C. For 20 minutes at 20 ° C. This is designated as a toner material solution (1).

  Next, the aqueous phase 1 liquid 306 parts container described above was weighed in a beaker. Next, while stirring at 12,000 rpm with a TK homomixer, the entire amount of the toner material solution (1) obtained by the above operation and 2.7 parts of the ketimine compound (1) were added to cause a urea reaction. When the particle size is large while observing the particle size and the particle size distribution with an optical microscope, the number of rotations for stirring is increased to 14000, and the process is further performed for 5 minutes. If smaller, change the stirring to 10,000 rpm and repeat the experiment. Next, the mixed solution was transferred to a kolben equipped with a thermometer equipped with a paddle-type stirring bar, heated to 45 ° C., and stirred at a peripheral speed of 4 m / s for 2 hours to obtain mother toner particles having a nearly spherical shape. Was. During the stirring, a starch solution is added to control the viscosity of the aqueous phase to 1000 to 5000 CP. Thereafter, the solvent was removed under reduced pressure at 50 ° C. or lower for 2 hours, filtered, washed and dried, and then subjected to air classification to obtain base particles having a nearly spherical shape.

Next, 100 parts of the obtained base particles and 0.25 part of a charge controlling agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were charged into a Q-type mixer (manufactured by Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine blade was set to 50 m / m. The operation time was set to sec, the operation was performed for 2 minutes, and the pause for 1 minute was performed 5 cycles, and the total processing time was set to 10 minutes.
Further, 0.5 parts of hydrophobic silica (H2000, manufactured by Clariant Japan Co., Ltd.) was added, the peripheral speed was set to 15 m / sec, and mixing was continued for 30 seconds for 1 minute, followed by 5 cycles to obtain a cyan toner. Next, 0.5 parts of hydrophobic silica and 0.5 parts of hydrophobic titanium oxide were mixed with a Henschel mixer to obtain Comparative Toner (5). Tables 2 and 3 show the evaluation results.

<Comparative Example 6>
A toner of Comparative Example 6 was produced by changing a part of the conditions of Production Example 6 in the same manner as in Comparative Example 5.
In a beaker, 14.3 parts of the above prepolymer (1), 55 parts of unmodified polyester (a), and 78.6 parts of ethyl acetate were stirred and dissolved. Next, 10 parts of rice wax (melting point: 83 ° C.) as a release agent and 7 parts of carbon black # 44 (manufactured by Mitsubishi Chemical) were added, and the mixture was stirred at 60 ° C. with a TK homomixer at 12,000 rpm for 5 minutes, and then mixed with a bead mill at 30 ° C. For 20 minutes at 20 ° C. This is designated as a toner material solution (1).

  Next, the aqueous phase 1 liquid 306 parts container described above was weighed in a beaker. Next, while stirring at 8000 rpm with a TK homomixer, the whole amount of the toner material solution (1) obtained in Example 1 and 2.7 parts of the ketimine compound (1) were added to cause a urea reaction. While observing the particle size and the particle size distribution with an optical microscope, the stirring is set at 8000 to 10000 rpm with the target of 8 μm. Next, the mixed solution was transferred to a kolben equipped with a thermometer equipped with a paddle-type stirring rod capable of a peripheral speed of 5 m / s or more, heated to 45 ° C., and stirred for 2 hours at a peripheral speed of 6 m / s. To obtain spindle-shaped base toner particles. During the stirring, a starch solution is added to control the viscosity of the aqueous phase to 3000 to 20000 CP. If the spindle type is insufficient, extend the stirring time. Thereafter, the solvent was removed under reduced pressure at 50 ° C. or lower for 1.0 hour, filtered, washed and dried, and then subjected to air classification to obtain spindle-shaped base particles.

Next, 100 parts of the obtained base particles and 0.25 part of a charge controlling agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were charged into a Q-type mixer (manufactured by Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine blade was set to 50 m / m. The operation time was set to sec, the operation was performed for 2 minutes, and the pause for 1 minute was performed 5 cycles, and the total processing time was set to 10 minutes.
Further, 0.5 parts of hydrophobic silica (H2000, manufactured by Clariant Japan Co., Ltd.) was added, the peripheral speed was set to 15 m / sec, and mixing was continued for 30 seconds for 1 minute, followed by 5 cycles to obtain a cyan toner. Next, 0.5 parts of hydrophobic silica and 0.5 parts of hydrophobic titanium oxide were mixed with a Henschel mixer to obtain Comparative Toner (6). Tables 2 and 3 show the evaluation results.

<Comparative Example 7>
The image of the toner of Comparative Example 5 of the present invention is evaluated using a modified model of an image NEO450 manufactured by Ricoh Co. described below. At this time, the image is evaluated on 100,000 sheets without the recycling system.

[Evaluation method]
(1) Tg measurement method A method for measuring Tg will be outlined. Shimadzu thermal analyzer DSC-60 was used as a device for measuring Tg.
First, about 5 mg of a sample is placed in an aluminum sample container, placed on a holder unit, and set in an electric furnace. Next, the sample is heated from room temperature to 150 ° C. at a rate of 10 ° C./min from room temperature in a nitrogen atmosphere, and then cooled to room temperature at a rate of 10 ° C./min. The sample was again heated to 150 ° C. at a rate of 10 ° C./min, and the DSC measurement was performed. As for Tg, using a DSC-60 analysis system, the intersection of the tangent line of the endothermic curve near Tg and the baseline was read and defined as Tg.

(2) Acid value According to the method specified in JIS K0070. However, if the sample does not dissolve, use dioxane or tetrahydrofuran as the solvent.

(3) Powder fluidity The bulk density was measured using a powder tester manufactured by Hosokawa Micron. The higher the flowability of the toner, the greater the bulk density. The following four grades evaluated.
×: less than 0.25 Δ: 0.25 to 0.30
：: 0.30 to 0.35
A: Over 0.35

(4) Heat Storage Stability After storing the toner at 50 ° C. for 8 hours, the toner was sieved with a 42-mesh sieve for 2 minutes. The residual ratio of toner having better heat resistance storage stability is smaller. The following four grades evaluated.
×: Over 30% Δ: 20 to 30%
：: 10 to 20%
◎: less than 10%

(5) Minimum fixing temperature Using a modified apparatus of imager NEO450 manufactured by Ricoh Co., Ltd. as a fixing roller, Ricoh type 6200 paper was set in this apparatus and a copy test was performed. The fixing roll temperature at which the residual ratio of the image density after rubbing the fixed image with a pad was 70% or more was defined as the fixing lower limit temperature.
* The fixing device was modified, and a metal cylinder of Fe material having a thickness of 0.34 mm was used for the metal cylinder of the fixing roller. The surface pressure was set to 1.0 × 10 ⁵ Pa.

(6) Hot offset occurrence temperature (HOT)
The fixing was evaluated in the same manner as the fixing lower limit temperature, and the presence or absence of hot offset to the fixed image was visually evaluated. The fixing roll temperature having the fixing roll temperature at which the hot offset occurred was defined as the hot offset occurrence temperature.

(7) Charge stability The charge amount at low temperature, low humidity and high temperature and high humidity is measured by a blow-off method, and the fluctuation width is evaluated.
It is necessary to use a silicone resin-coated iron powder for the carrier and measure the environment under the conditions of 30 ° C-90RH% and 10 ° C-30RH%, and the change should be small.
×: Not usable △: Large difference ○: Somewhat large difference ◎: Small difference and stable

(8) Cleaning properties The surface of the latent image carrier immediately after being cleaned by the cleaning blade is visually observed, the toner adhered to the surface of the carrier is adhered to a transparent tape, which is attached to a blank sheet of paper, and a Macbeth densitometer from above. Measure the image density with.

(9) Gradation This is an evaluation of a 10-step chart.

Recyclability evaluation <Preparation of developer>
50 parts of toner having a particle size of 10 to 1 μm and 950 parts of a silicon resin film carrier (silicon resin: KR250, manufactured by Shin-Etsu Chemical Co., Ltd., core material carrier 70 μm) were mixed and sufficiently shaken to obtain a developer. Using this developer, an image evaluation of 100,000 sheets was performed using a remodeled imager NEO450 manufactured by Ricoh equipped with a recycling system.

(10) Fine powder content After 100,000 copies were made, the particle size distribution of the toner was determined with a Coulter Counter TA-2 (manufactured by Coulter). In this case, a 1% NaCl solution was used for the electrolyte, and a dry well was used for the dispersant. From the data of the particle size distribution outputted by the computer, the particle size of 5.04 μm was determined as fine powder, and the number% of the fine powder was determined.

(11) Toner Cohesion Degree After 100,000 times of copying, the toner in the developing device was extracted and the presence or absence of toner agglomerates was examined.
The evaluation was “good” when little toner agglomerates were observed, and “good” when toner agglomerates were slightly observed but at a practical level. In general, a case where there is a problem is indicated by “×”.

(12) Fluidity of Toner After 100,000 times of copying, the toner in the developing device was extracted and the fluidity of the toner was visually examined.
The evaluation was evaluated as “○” when good, “良好” when slightly inferior but at a practical level, and “×” when extremely poor and problematic in practical use.

(13) Durability of Toner The initial solid image density and the image density after copying 100,000 sheets were evaluated according to the following criteria.
：: A sharp image is obtained with little decrease in density.
Δ: Density decrease but acceptable level.
×: Unacceptable level due to density reduction.

(14) Image background stain evaluation In the durability evaluation, the background stain level of the image is determined.
Rank 1: The image is clear without any background dirt.
Rank 2: A little soiling is recognized, but the image quality is acceptable.
Rank 3: A level at which soiling is recognized and the image quality is unacceptable.

(15) Image evaluation An abnormal image is checked in the durability evaluation.
Check items: Black spots, image blurring, and carrier adhesion.

In addition, the acid value and Tg in Table 1 represent the measurement results of the polyester described in the column of "Binder used (unmodified)".

From the results shown in Tables 2 and 3, Comparative Examples 2 and 4 have a small particle size and a high degree of cohesion, and have poor fluidity, so that soiling occurs.
Further, in Comparative Examples 1, 2, and 4, since SF-1 is low and almost spherical, blade cleaning properties are inferior.
Further, Comparative Examples 1 and 2 have a high fixing lower limit temperature because of a high Tg.
Comparative Example 3 has irregularities and irregular shapes, has a high fine powder content, does not satisfy any of the toner aggregation degree, durability and fluidity, and has poor cleaning properties.
In Comparative Example 4, since the styrene acrylic resin was used, the minimum fixing temperature was high although the particle size was small.
In Comparative Example 5, cleaning failure occurred due to low SF-1.
In Comparative Example 6, the gradation was lowered and the low-temperature fixability was lowered due to the large particle diameter.
Further, in Comparative Example 7, a running test was performed without the recycling device, and as a result, the cleaning failure generated in Comparative Example 5 did not occur.
On the other hand, in Examples 1 to 4, the generation of fine powder in the machine is small, and there is no problem with the image and the inside contamination. In particular, the blade cleaning property due to the high SF-1 is excellent.
However, from Example 2, when SF-1 is too large, fine powder is apt to be generated, and the tendency of the cleaning property to slightly decrease is observed.
In Example 4, when the particle diameter is small and Dv / Dn is small, the fixing effect and the gradation are excellent.

  The dry toner according to the present invention is excellent in recyclability, reduces the reduction in image sharpness due to charging and agglomeration due to surface exudation by wax, and provides high quality images with less transfer residual toner in an apparatus using blade cleaning. Things.

The toner, developer, toner container, image forming apparatus (developing apparatus), and process cartridge of the present invention provide a toner recycling system in an image forming method using an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like. It can be suitably used for an adopted image forming method.

FIG. 1 is a diagram illustrating a digital copying machine (image forming apparatus) as an example of an image forming apparatus used in the present invention. FIG. 2 is an enlarged schematic view of a main part of an example of the image forming apparatus of the present invention. FIG. 3 is an enlarged schematic view of an example of a recycling apparatus of the image forming apparatus of the present invention. FIG. 4 is a diagram showing a schematic configuration of an example of an image forming apparatus having the process cartridge of the present invention. FIG. 5 is a schematic configuration diagram for explaining the layer configuration of the photoconductor of the present invention. FIG. 6 is a view showing a developing device of the present invention. FIG. 7 is a diagram illustrating charging characteristics of contact charging. FIG. 8A shows an example of a roller contact charging device, and FIG. 8B shows an example of a brush contact charging device.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charger 3 Exposure means 4 Developing means 5 Transfer means 5a Transfer belt 6 Cleaning means 6a Cleaning blade 6b Brush roller 6c Discharge port 7 Document mounting table 8 Reading means 9 Feeding device 10 Fixing means 11 Cleaning means 12 Tank 13 Recycling device 13a Transport pipe 13b Rotary screw conveyor 20 Process cartridge 21 Photoconductor 22 Charging means 23 Developing means 24 Cleaning means 40 Developing tank 41 Toner hopper 42 Magnetic permeability sensor 43 Supply roller 44 Stirring member 45 Paddle wheel 46 Developing roller 47 Developing doctor 500 Electrophotographic photoreceptor 501 Support 502 Photoconductive layer 503 Surface layer 504 Charge injection blocking layer 505 Charge generation layer 506 Charge transport layer 620 Developing device 621 Developing sleeve 62 2 Power supply 623 Developing unit 624 Photoconductor drum

Claims (26)

  A toner used in an image forming method employing a toner recycling system and containing at least a modified polyester resin, a coloring agent, a release agent, and a coating, wherein the volume average particle diameter (Dv) of the toner is 4.0. 6.0 μm, the ratio Dv / Dn of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.00 to 1.30, and the toner has a shape factor SF-1 of 140 to 200. At least in an organic solvent, a resin capable of reacting with a compound having an active hydrogen group, a step of dissolving or dispersing a composition containing a colorant and a release agent,
A step of dispersing the solution or dispersion in an aqueous medium while causing a resin capable of reacting with a compound having an active hydrogen group to undergo at least one of extension and crosslinking.
Removing the organic solvent after or during the reaction of at least one of the extension and crosslinking,
The toner according to claim 1, which is obtained by a production method having:   The toner according to claim 2, wherein the composition contains a compound having an active hydrogen group.   3. The toner according to claim 2, wherein the compound having an active hydrogen group is added in a step of dispersing the compound in an aqueous medium.   The toner according to any one of claims 2 to 4, wherein the aqueous medium contains polymer fine particles and is capable of forming the coating.   The toner according to claim 1, wherein a ratio Dv / Dn of the toner is 1.00 to 1.20.   The toner according to any one of claims 1 to 6, wherein the shape factor SF-1 of the toner is from 150 to 180.   The toner according to any one of claims 1 to 7, wherein the content of fine powder having a particle diameter of 2 µm or less is 15% or less on a number basis in a particle size distribution measured by a flow type particle image measuring device of the toner.   The toner according to any one of claims 1 to 8, wherein the toner has an average circularity measured by a flow type particle image analyzer of 0.90 to 0.95.   The toner according to claim 5, wherein the polymer fine particles have a glass transition point of 50 to 110 ° C. 7.   The polymer fine particles are at least one selected from a vinyl resin, a polyurethane resin, an epoxy resin, a polyester resin, a polyamide resin, a polyimide resin, a silicon resin, a phenol resin, a melamine resin, a urea resin, an aniline resin, an ionomer resin and a polycarbonate resin. The toner according to claim 5, comprising one resin.   12. The toner according to claim 5, wherein the volume average particle diameter of the polymer fine particles is 10 to 200 nm.   3. The toner according to claim 2, further comprising, before the step of removing the organic solvent, stirring the obtained dispersion in a stirring tank provided with a stirrer having a peripheral speed of 5 m / s or more to deform the spherical particles into a spindle shape.   14. The toner according to claim 1, wherein the modified polyester resin is a urea modified polyester resin.   15. The toner according to claim 1, further comprising an unmodified polyester resin.   The toner according to claim 15, wherein the unmodified polyester resin has a glass transition point of 40 to 70C.   17. The toner according to claim 15, wherein the unmodified polyester resin has an acid value of 1 to 30 mgKOH / g.   The toner according to any one of claims 1 to 17, which is a toner used for a two-component developer.   A toner used in an image forming method employing a toner recycling system, including a toner and a carrier, wherein the toner contains at least a modified polyester resin, a colorant, a release agent, and a coating, and has a volume of The average particle diameter (Dv) is 4.0 to 6.0 μm, and the ratio Dv / Dn between the volume average particle diameter (Dv) and the number average particle diameter (Dn) is 1.00 to 1.30; And a developer having a shape factor SF-1 of 140 to 200. A photoreceptor, charging means for charging the photoreceptor, exposure means for exposing the photoreceptor to form an electrostatic latent image, and a toner loaded therein, and developing the electrostatic latent image using toner Developing means for forming a toner image, transfer means for transferring the toner image carried on the photoreceptor to a transfer material, cleaning means for cleaning toner remaining on the photoreceptor surface after the transfer using a blade, Recycling means for reusing the cleaned toner for development,
An image forming apparatus, wherein the toner is the toner according to any one of claims 1 to 18.   The image forming apparatus according to claim 20, wherein the photoconductor is an amorphous silicon photoconductor.   22. The image forming apparatus according to claim 20, wherein an alternating electric field is applied when developing the latent image on the photoconductor.   23. The image forming apparatus according to claim 20, wherein the charging device is a charging device that performs charging by bringing a charging member into contact with the latent image carrier and applying a voltage to the charging member.   A photoreceptor, charging means for charging the photoreceptor, developing means for loading the toner, developing the electrostatic latent image with toner to form a toner image, and removing toner remaining on the photoreceptor surface after transfer. 19. A process cartridge which is integrally provided with at least one means selected from cleaning means for cleaning using a blade, and is detachable from an image forming apparatus main body. A process cartridge comprising the toner according to any one of the above. A charging step of charging the photoreceptor, an exposure step of exposing the photoreceptor to form an electrostatic latent image, and loading a toner, and developing the electrostatic latent image using the toner to form a toner image A developing step, a transfer step of transferring a toner image carried on the photoreceptor to a transfer material, a cleaning step of cleaning the toner remaining on the photoreceptor surface after the transfer using a blade, and cleaning the cleaned toner. A recycling process for reuse in development,
An image forming method, wherein the toner is the toner according to any one of claims 1 to 18.   A toner which is used in an image forming method employing a toner recycling system and contains at least a modified polyester resin, a colorant, and a release agent, wherein the toner has a surface coated with a fine particle polymer, and a volume average of the toner. The particle diameter (Dv) is 4.0 to 6.0 μm, and the ratio Dv / Dn of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.00 to 1.30; A toner having a shape factor SF-1 of 140 to 200.