JP3367974B2 - Toner for developing electrostatic images - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner used in electrophotography, electrostatic printing and magnetic recording, and particularly to untransferred toner remaining on a latent image carrier after development and transfer. The present invention relates to an electrostatic charge image developing toner used in an image forming method that utilizes a system in which toner is collected in a cleaning step and reused.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
And Japanese Patent Publication No. 43-24748. Generally, a photoconductive substance is used to form an electric latent image on a photoconductor by various means, and then the latent image is developed with a toner, and a toner image is formed on a transfer material such as paper if necessary. After transfer, the image is fixed by heating, pressure, heating and pressurizing, or solvent vapor to obtain a copy.

Various methods and apparatuses have been developed for the final step of fixing the toner image on a sheet such as paper. The most popular method at present is a pressure heating method using a heating roller.

In the pressure-bonding heating method using a heating roller, fixing is performed by allowing the toner image surface on the sheet to be fixed to pass under pressure while contacting the surface of a heating roller whose surface is formed of a material having releasability for toner. It is something to do. In this method, the surface of the heat roller and the toner image on the sheet to be fixed come into contact with each other under pressure, so that the thermal efficiency at the time of fusing the toner image on the sheet to be fixed is extremely good, and quick fixing is required. And is very effective in high speed electrophotographic copying machines. However, in the above method, since the surface of the heat roller and the toner image are in contact with each other under pressure in a molten state, a part of the toner image adheres to the surface of the fixing roller and is transferred, and this is retransferred to the next sheet to be fixed and offset. This may cause a phenomenon and stain the sheet to be fixed. Preventing toner from adhering to the surface of the heat fixing roller is one of the important conditions of the heat roller fixing method.

Conventionally, for the purpose of preventing the toner from adhering to the surface of the fixing roller, for example, the roller surface is formed of a material having excellent releasability from the toner (for example, silicone rubber or fluorine resin), and the surface thereof is further formed. In order to prevent offset and to prevent fatigue of the roller surface, the roller surface is coated with a thin film of a liquid having a good releasing property such as silicone oil. However, this method is extremely effective in preventing toner offset, but has a problem that the fixing device becomes complicated because a device is required to supply the offset preventing liquid.

Therefore, the direction of preventing the offset by supplying the offset preventing liquid is not preferable, and it is the current situation that development of a toner having a wide fixing temperature range and high offset resistance is desired. Therefore, in order to increase the releasability of the toner, a method of adding a wax such as low molecular weight polyethylene or polypropylene that is sufficiently melted when heated is also used. Although the use of wax is effective for preventing offset, it increases the cohesiveness of the toner, makes the charging characteristics unstable, and easily lowers the durability. Therefore, as other methods, various attempts have been made to improve the binder resin.

For example, in order to prevent offset, a method is known in which the glass transition temperature (Tg) and the molecular weight of the binder resin in the toner are increased to improve the melt viscoelasticity of the toner. However, when the offset phenomenon is improved by such a method, the fixing property becomes insufficient, and there is a problem that the fixing property under low temperature (that is, low temperature fixing property) required for high-speed copying machines and energy saving is deteriorated. Occurs.

On the other hand, in order to improve the fixing property of the toner, it is necessary to reduce the viscosity of the toner at the time of melting and increase the adhesion area with the fixing base material. Therefore, it is required to reduce the Tg and the molecular weight of the binder resin used.

Since the low-temperature fixing property and the offset preventing property are contradictory, it is very difficult to develop a toner satisfying these functions at the same time.

In order to solve these problems, for example, Japanese Patent Publication No. 51-23354 proposes a toner comprising a vinyl polymer which is appropriately crosslinked by adding a crosslinking agent and a molecular weight modifier. In the -6805 publication, α,
A toner having a broad molecular weight distribution such that the ratio of the weight average molecular weight to the number average molecular weight of β-unsaturated ethylenic monomer as a constitutional unit is 3.5 to 40 has been proposed. Further, a toner has been proposed in which a blend-type resin in which Tg, molecular weight, gel content and the like are specified in a vinyl-type polymer is used.

Certainly, the toners according to these proposals have a lower fixing temperature (the lowest temperature at which fixing is possible) and an offset temperature (a temperature at which offset begins to occur) than toners made of a single resin having a narrow molecular weight distribution. Although the feasible fixing temperature range is widened, it is difficult to sufficiently lower the fixing temperature when sufficient offset prevention performance is provided. On the contrary, if the low temperature fixability is emphasized, there is a problem that the offset prevention performance becomes insufficient.

For example, JP-A-56-158340 proposes a toner comprising a low molecular weight polymer and a high molecular weight polymer. Since it is difficult to contain a crosslinking component in this binder resin, in order to improve the offset resistance in a high performance, the molecular weight of the high molecular weight polymer is increased or the ratio of the high molecular weight polymer is increased. There is a need. This direction is a direction in which the pulverizability of the resin composition is significantly reduced, and it is difficult to obtain a practically satisfactory product.
Further, regarding a toner obtained by blending a low molecular weight polymer and a crosslinked polymer, JP-A-58-86558 proposes a toner containing a low molecular weight polymer and an insoluble and infusible high molecular weight polymer as main resin components. ing. If you follow that method,
It seems that the fixing property of the toner and the pulverizability of the resin composition are improved. However, the weight average molecular weight / number average molecular weight (Mw / Mn) of the low molecular weight polymer is as small as 3.5 or less, and the insoluble and infusible high molecular weight polymer is 40 to 90.
When it is as large as wt%, it is difficult to satisfy both the offset resistance of the toner and the pulverizability of the resin composition with high performance. In practice, it is extremely difficult to produce a toner that sufficiently satisfies the fixability and the offset resistance unless it is a fixing machine having a device for supplying an offset preventing liquid. Furthermore, when the amount of insoluble and infusible high molecular weight polymer increases, the melt viscosity becomes extremely high in the heat kneading at the time of toner preparation, so it is necessary to heat knead at a temperature much higher than usual, and as a result, the heat of the additive There is a problem that the toner characteristics are degraded due to the decomposition.

JP-A-60-166958 proposes a toner comprising a resin composition obtained by polymerization in the presence of a low molecular weight α-methylstyrene polymer having a number average molecular weight of 500 to 1,500. ing.

Particularly, in this publication, the number average molecular weight (Mn) is preferably in the range of 9,000 to 30,000. If Mn is increased in order to improve the offset resistance, the fixability and the pulverizability at the time of toner production become problems in practical use. Therefore, it is difficult to satisfy the offset resistance and the grindability of the resin composition with high performance. As described above, the toner having poor pulverizability during the toner production is not preferable because the production efficiency during the toner production is lowered and the toner having a rough toner property is apt to be mixed in, which may cause a jumped image.

Japanese Patent Laid-Open No. 56-16144 discloses a GPC.
In the molecular weight distribution according to, the molecular weight is 10 ³ to 8 × 10 ^4.
And a toner containing a binder resin component having at least one local maximum value in each region having a molecular weight of 10 ^{5 to} 2 × 10 ⁶ . In this case, the crushing property of the binder resin component, the offset resistance of the toner, the fixing property, the filming and fusion prevention to the photoconductor, and the developing property are excellent. Further, improvement in offset resistance and fixability of the toner has been demanded. In particular, it is difficult for the resin to meet today's strict requirements while further improving the fixability and maintaining or improving various other performances.

As described above, it is extremely difficult to achieve both high performance relating to toner fixing (low-temperature fixing property and offset prevention property) and pulverizability during toner production with high performance.
Particularly, pulverizability at the time of toner production is an important factor in today's direction of reducing the particle size of toners due to the demands for high quality, high resolution of copied images and high reproducibility of fine lines.
Since the crushing process requires a very large amount of energy, improvement of crushability is important from the viewpoint of energy saving. The phenomenon of fusion of the toner to the inner wall of the crushing device is also likely to occur in the toner having good fixing performance, which may deteriorate the crushing efficiency.

In the copying step, there is a step of cleaning the toner remaining on the photoconductor after transfer. Nowadays, cleaning with a blade (blade cleaning) is becoming popular in terms of downsizing, weight saving, and reliability of the apparatus. As the life of the photoconductor is extended, the diameter of the photoconductor drum is reduced, and the speed of the system is increased, fusion resistance and filming resistance of the photoconductor to the photoconductor are becoming severe.
In particular, the amorphous silicon photoconductor that has recently been put into practical use has extremely high durability, and the life of OPC (organic photoconductor) has been extended. Therefore, various performances required for toner have been advanced. .

For miniaturization of the device, it is necessary to properly store each element in a small space. Therefore, the space through which the cooling air flows is reduced, and the heat sources of the fixing device and the exposure system are very close to the toner hopper and the cleaner, so that the toner is exposed to a high temperature atmosphere. for that reason,
Further, it has become impossible to put into practical use unless the toner has excellent blocking resistance.

As a method for improving the above-mentioned problems, the applicant of the present application disclosed a special resin in which a low molecular weight resin was added during suspension polymerization in Japanese Patent Application Laid-Open No. 63-223662. According to the above, even with a high-speed machine of 50 sheets or more per minute of A4 size paper, sufficient fixing property is not yet obtained, and further, the outflow of toner from the cleaning member in contact with the fixing roller easily stains the fixed image. A problem was found.

For high-speed machines that exceed 50 sheets per minute, 1
Even if the amount of offset per sheet is extremely small, the number of sheets passed is enormous, so the amount of offset material to the fixing roller becomes a considerable amount, which causes failure of the fixing device.
In order to remove this minute amount of offset material, a fixing cleaning member such as a silicone rubber cleaning roller or a web is attached in contact with the fixing roller. Conventional toner binder resins are designed mainly for low-temperature fixability and anti-offset properties, and are not designed to maintain a high melt viscosity up to a high temperature of over 200 ° C. Therefore, the toner substance adhering to the fixing cleaning member is present at the set temperature of the fixing roller for a long time, so that the melt viscosity is lowered, and the fixing roller temperature overshoots more than the set temperature of the fixing roller when the copying machine is turned on. In that case, the temperature of the fixing roller becomes higher than 200 ° C., the melt viscosity of the adhered toner is remarkably lowered, and the toner is transferred to the fixing roller again, so that the transfer material is contaminated.

Japanese Unexamined Patent Publication No. 1-172843 and 1
No. 172844 discloses 3 × 10 ^{3 to} 5 × 10 ³ ,
And a peak at 1.5 × 10 ^{5 to} 2.0 × 10 ⁶ ,
The peak area in the region of 1.5 × 10 ^{5 to} 2.0 × 10 ⁶ is 40 to 60%, or the gel content is 1 to 10
% Toner is proposed. Certainly it is good for medium- and low-speed machines, but offset resistance in high-speed machines,
Fixability cannot be fully dealt with.

Further, in the transfer step, all the toner on the photosensitive member (latent image carrier) is not transferred, and
About 0 to 20 weight percent remains on the photoreceptor. In this way, the toner (untransferred toner) remaining on the photoconductor is
It was collected by the cleaning process and was discharged outside the system as so-called waste toner, so that it could not be used again. However, in recent years, the demand for copying machines has increased, and the demand for machines with a large copy volume, that is, high-speed copying machines, is increasing. Since a large amount of waste toner is generated in such a high-speed copying machine, there is a risk of causing environmental pollution when treated as waste (waste plastic). Therefore, recently, a study of reusing the waste toner, that is, a study of reuse of the toner has been widely conducted. If the waste toner can be reused, the toner can be effectively used, the space in the machine can be simplified, and the machine can be made compact.

However, when the waste toner is used again in the developing step, there have been adverse effects such as a decrease in the reflection image density, deterioration of background fog and reversal fog, and toner scattering.

The characteristics of the toner applied to such a reuse system are as described above, that is, developability, low temperature fixing property, anti-offset property, anti-blocking property, anti-filming property and pulverizing property. In addition to the above, properties such as strong mechanical stress, excellent durability, and excellent transportability of waste toner to the developing process are also required.

To meet these demands, various toners have been devised so far. For example, Japanese Patent Laid-Open No. 1-214
No. 874, a toner using a specific polyester resin containing an aliphatic diol as a binder resin, and further, in Japanese Patent Laid-Open No. 2-110572, a metal-crosslinked styrene-acryl copolymer is used as a binder resin. A toner obtained by adding a large amount of this and a large amount of polyolefin has been devised. However, in any of the inventions, the novelty of the toner composition itself is poor, and there is a high possibility that adverse effects such as deterioration of blocking resistance will occur.

As described above, the performances required for toners are often reciprocal with each other, and it is increasingly desired in recent years to satisfy these requirements even when the waste toner is reused. ing.

[0027]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrostatic charge image developing toner which solves the above problems, that is, an electrostatic charge image developing toner suitable for a recycling system for reusing the toner. It is a thing.

The objects of the present invention are listed below.

An object of the present invention is to provide a toner suitable for a heat roll fixing system which does not apply oil.

An object of the present invention is to provide a toner which can be fixed at a low temperature and has excellent offset resistance.

An object of the present invention is to fix a toner at a low temperature, and to fuse and film on a photosensitive member even in a high speed system.
Another object is to provide a toner that does not generate even after long-term use.

An object of the present invention is to provide a toner which is fixed at a low temperature and has excellent blocking resistance, and which can be sufficiently used even in a high temperature atmosphere in a small machine.

An object of the present invention is to provide a toner which can be efficiently and continuously produced since the pulverized material is fixed at a low temperature and does not adhere to the inner wall of the apparatus in the pulverizing step during toner production.

An object of the present invention is to provide a toner having excellent production efficiency because it has excellent offset resistance and crushability.

An object of the present invention is to provide a toner suitable for a cleaning system using a blade.

An object of the present invention is to provide a toner capable of forming a stable and good developed image with less crushing and less generation of coarse powder and therefore less scattering around the image.

An object of the present invention is to provide a toner capable of obtaining a sharp image from the beginning because it is not mechanically damaged even when continuous copying or reuse of waste toner is performed.

An object of the present invention is to provide a toner which maintains a high reflection image density throughout the waste toner reuse system and does not cause background fog or toner scattering.

[0039]

SUMMARY OF THE INVENTION According to the present invention, a latent image on a latent image carrier is developed to form a toner image, and the formed toner image is transferred from the latent image carrier to a transfer material and transferred. After cleaning the latent image bearing member, the toner on the latent image bearing member is collected, and the collected toner is supplied to the developing section to be used for the electrostatic image development used in the image forming method used in the developing step. A toner, which contains at least a binder resin and a colorant, has two or more peaks or shoulders in a molecular weight distribution of a resin component by gel permeation chromatography (GPC), and has a peak in a region of a molecular weight of 400,000 or more. or have one of the shoulders, further, the electrostatic that the average molecular weight calculated from GPC, the ratio Mw / Mn of the weight average molecular weight (Mw) to number average molecular weight (Mn), characterized in that a 40 to 46 Those relating to toner image development.

The present invention also provides a toner for developing an electrostatic charge image used in the above-mentioned image forming method, which contains at least a binder resin and a colorant, and the molecular weight distribution of the resin component by gel permeation chromatography (GPC). Has two or more peaks or shoulders, and has one peak or shoulder in the region of molecular weight of 400,000 or more. Furthermore, in the average molecular weight calculated by GPC, the weight average molecular weight (Mw) and the number average are Ratio of molecular weight (Mn) Mw / M
The present invention relates to an electrostatic charge image developing toner, wherein n is 41 to 47 and is obtained by solution-mixing at least one or more kinds of polyolefin release agents and removing the solvent. .

Further, the present invention is a toner for developing an electrostatic charge image used in the above-mentioned image forming method, which contains at least a binder resin, a colorant and a metal compound, and the binder resin contains a carboxylic acid-containing monomer. A polymer having another copolymerizable monomer as a constituent component, and gel permeation chromatography (GP) of a resin component.
In the molecular weight distribution according to C), it has two or more peaks or shoulders, and one peak or shoulder in the region of molecular weight of 500,000 or more. Furthermore, in the average molecular weight calculated by GPC, the weight average molecular weight ( Mw) and number average molecular weight (M
The present invention relates to an electrostatic charge image developing toner characterized in that the ratio Mw / Mn of n) is 52 to 63 .

The present invention will be described in detail below.

In the high-speed copying machine, the demand thereof has been increasing more and more recently, and the demands of users have also been diversified accordingly. For this reason, attempts have been made to increase the copy volume while always maintaining good image quality with a higher-speed copying machine. In this way, by increasing the copy volume, the amount of toner consumed also increases, and the amount of untransferred toner, that is, waste toner also increases accordingly. Until now, this untransferred toner was scraped off by a cleaning blade or the like, then sent to a cleaner, further discharged outside the system, and could not be reused. The reason for this is that when the waste toner is reused, there are adverse effects such as a reduction in reflection image density, deterioration of background fog and reverse fog, and occurrence of toner scattering.

Therefore, the present inventors collected various toners on the developing sleeve from the start of copying and conducted various studies in order to investigate the cause of these adverse effects. As a result, the toner shape was changed before and after the above-mentioned adverse effects began to occur.

That is, as a result of observation using a scanning electron microscope (SEM), there are many toners having harmful effects, that is, waste toners, whose surface is peeled off or broken from the inside. I understood.

When the reason for this is examined, the untransferred toner (waste toner) is mechanically impacted in the cleaner when it is scraped off by the cleaning blade on the photosensitive drum or when it is sent to the developing step using the conveying screw. It turned out that the factor is large.

From the above, in the system in which the waste toner is reused, various performances required for the toner are: excellent developing property, low temperature fixing property and anti-offset property; In addition to well-known performance such as excellent grinding ability, excellent pulverizability, etc., strong resistance to mechanical impact and excellent durability-Waste toner conveyance to the development process It is excellent.

In order to satisfy all of these performances, the inventors of the present invention have made diligent studies, and as a result, it has been found that giving a characteristic to the molecular weight distribution of the resin component is an extremely effective means, and the present invention has been completed. is there.

Next, the binder resin used in the electrostatic image developing toner of the present invention will be described.

The resin component used in the toner of the present invention is
A GPC chart is characterized by having a plurality of peaks or shoulders and having one peak or shoulder in a region having a molecular weight of 400,000 or more. Such a component in the high molecular weight region has excellent releasability, works effectively as a component that suppresses flow at high temperatures and improves offset resistance, and prevents toner from flowing out from the cleaning member of the fixing device. it can. Further, when the toner is turned into a toner, strength can be given to the toner, so that the obtained toner becomes tough and is not destroyed by mechanical stress such as cleaning.
Also, the same developability as that of the replenishment toner can be obtained.

Further, in the toner of the present invention, in the average molecular weight calculated from GPC of the binder resin, the ratio Mw / M of the weight average molecular weight (Mw) to the number average molecular weight (Mn).
n is 10 or more, preferably 10 to 95. By doing so, the binder resin contains the low-molecular weight component and the high-molecular weight component in a well-balanced manner, and has a wide molecular weight distribution including the molecular weight component between them, so that both effects can be effectively exhibited. .

When Mw / Mn is less than 10, the amount of the low molecular weight component is small, so that sufficient toner fixability and pulverizability during toner production cannot be obtained.

In the present invention, the molecular weight distribution of the chromatogram by GPC (gel permeation chromatography) using THF as a solvent in the tetrahydrofuran (THF) soluble portion of the resin is measured under the following conditions.

The measurement sample is prepared as follows.

About 0.5 to 5 mg / ml of the sample and THF
After mixing at a concentration of (for example, about 5 mg / ml) and leaving it at room temperature for several hours (for example, 5 to 6 hours), shake it well and mix the THF and the sample well (until there is no union of the samples), Furthermore, it is left to stand for 12 hours or more (for example, 24 hours) at room temperature. At this time, the time from the start of mixing the sample and THF to the end of the standing should be 24 hours or more. Then sample processing filter (pore size 0.4
5 to 0.5 μm, for example, Mysholydisc H-2
5-2, manufactured by Tosoh Co., Ltd., Excicrodisc 25CR Gelman Science Japan Co., Ltd., etc. are preferably used) are used as GPC samples. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

The effect of the present invention is that the binder resin contained in the toner of the present invention contains 10% by weight or less (more preferably 5% by weight or less) of the resin component remaining as an insoluble component in the above filter treatment. It is preferable for exhibiting it.

In the GPC measuring apparatus, the column was stabilized in a heat chamber at 40 ° C., and THF as a solvent was flown through the column at this temperature at a flow rate of 1 ml / min to obtain T
About 100 μl of HF sample solution is injected for measurement. When measuring the molecular weight of a sample, calculate the molecular weight distribution
It is calculated from the relationship between the logarithmic value and the count number of a calibration curve prepared by using several kinds of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, a molecular weight of 10 ² to 1 manufactured by Tosoh Corporation or Showa Denko KK
Used of about 0 ^7, it is appropriate to use at least about 10 standard polystyrene samples. R for the detector
An I (refractive index) detector is used. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns, for example, shodex GPC K manufactured by Showa Denko KK
F-801, 802, 803, 804, 805, 80
Combination of 6,807,800P and T made by Tosoh Corporation
SKgel G1000H (H _XL ), G2000H (H
_XL ), G3000H (H _XL ), G4000H (H _XL ),
G5000H (H _XL ), G6000H (H _XL ), G70
The combination of 00H (H _XL ) and TSKguardcolumn can be mentioned.

Generally, in the measurement of GPC chromatogram, the measurement starts from the baseline on the high molecular weight side from the starting point of the chromatogram, and the low molecular weight side measures about 40 molecular weight.
Measure to 0.

Examples of the binder resin that can be used in the toner of the present invention include vinyl resins, polyester resins, polyurethanes, epoxy resins, phenol resins and the like. Of these, vinyl resins are particularly preferable.

Examples of the comonomer for obtaining the vinyl resin are as follows.

For example, styrene, o-methylstyrene, m
-Methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene,
2,4-dimethylstyrene, pn-butylstyrene,
Styrene and its derivatives such as p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene and pn-dodecylstyrene; ethylene, Ethylenically unsaturated monoolefins such as propylene, butylene, isobutylene; unsaturated polyenes such as butadiene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride; vinyl acetate, vinyl propionate, benzoe Vinyl esters such as vinyl acetate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate. , Meta Phenyl acrylic acid, dimethylaminoethyl methacrylate, alpha-methylene aliphatic monocarboxylic acid esters such as diethylaminoethyl methacrylate;
Methyl acrylate, ethyl acrylate, acrylic acid n-
Butyl, isobutyl acrylate, propyl acrylate,
Acrylic esters such as n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; N-vinyl pyrrole, N-vinyl carbazole, N
-N- such as vinylindole and N-vinylpyrrolidone
Vinyl compounds; vinyl naphthalene compounds; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide; and vinyl monomers used alone or in combination of two or more.

Of these, a combination of monomers that forms a styrene copolymer or a styrene / acrylic copolymer is preferable.

Further, by introducing an acid component into the vinyl resin,
It is more preferable in the present invention to have polarity. In this case, the acid component that can be preferably used, that is, the carboxylic acid-containing monomer includes the following dicarboxylic acid half-ester monomers. Monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monoallyl maleate, monophenyl maleate, monomethyl fumarate,
Half-esters of α, β-unsaturated dicarboxylic acids such as monoethyl fumarate, monobutyl fumarate, monophenyl fumarate and the like; n-butenyl monobutyl succinate, n-
Monomethyl octenyl succinate, Monoethyl n-butenylmalonate, Monomethyl n-dodecenyl glutarate, n
-Half esters of alkenyl dicarboxylic acids such as monobutyl butenyl adipate; half esters of aromatic dicarboxylic acids such as phthalic acid monomethyl ester, phthalic acid monoethyl ester, phthalic acid monobutyl ester, etc .;

The dicarboxylic acid half-ester as described above is 1 for all monomers constituting the binder resin.
-30 wt%, preferably 3-20 wt% may be added.

The half ester monomer of the dicarboxylic acid is selected because the suspension polymerization method is preferable as the method for producing the resin. This is because, in the suspension polymerization, it is not appropriate to use an acid monomer having a high solubility in an aqueous suspension, and an ester having a low solubility is preferably used.

The method of synthesizing the resin composition according to the present invention is as follows:
Basically, a method of synthesizing two or more polymers is preferable.
That is, it is a method in which a low molecular weight polymer soluble in a polymerization monomer is dissolved in the polymerization monomer and the monomer is polymerized to obtain a resin composition. In this case, a composition is formed in which the former and latter polymers are uniformly mixed. The low molecular weight polymer in the resin composition used in the present invention can be obtained by a commonly used polymerization method such as a bulk polymerization method or a solution polymerization method.

In the bulk polymerization method, a low molecular weight polymer can be obtained by increasing the termination reaction rate by polymerizing at a high temperature, but it is difficult to control the reaction.
In the solution polymerization method, it is possible to easily obtain a low molecular weight polymer or copolymer under mild conditions by utilizing the difference in radical chain transfer depending on the solvent and adjusting the amount of polymerization initiator used and the reaction temperature. It is preferable as a polymerization method for obtaining a low molecular weight polymer or copolymer in the resin composition used in the present invention.

As the solvent used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, benzene or the like can be used. In the case of a styrene monomer mixture, xylene, toluene or cumene are preferred. The solvent is appropriately selected depending on the polymer to be polymerized. As the polymerization initiator, di-tert-butyl peroxide, tert-butyl peroxybenzoate, benzoyl peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4dimethylvaleronitrile) ) And the like. The polymerization initiator is
It is used at a concentration of 0.05 parts by weight or more (preferably 0.1 to 15 parts by weight) with respect to 100 parts by weight of the monomer. The reaction temperature varies depending on the solvent used, the polymerization initiator or the polymer to be polymerized, but is preferably 70 ° C to 230 ° C. The solution polymerization is preferably carried out with 30 parts by weight to 400 parts by weight of the monomer per 100 parts by weight of the solvent. Further, it is also preferable to mix another polymer or copolymer in the solution at the end of the polymerization. In that case, several kinds of polymers or copolymers can be mixed well.

As a polymerization method for obtaining a high molecular weight component in the highly crosslinked region, an emulsion polymerization method or a suspension polymerization method is preferable.

Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier and polymerization is carried out using a water-soluble polymerization initiator. . In this method, the heat of reaction can be easily adjusted, and the termination reaction rate is low because the phase in which the polymerization is performed (oil phase consisting of polymer and monomer) and the aqueous phase are different, resulting in a high polymerization rate. A high degree of polymerization can be obtained.
Further, in the production of toner, due to the relatively simple polymerization process and the fine particles of the polymerization product,
Since it is easy to mix with a colorant, a charge control agent and other additives, it is advantageous as a method for producing a binder resin for a toner as compared with other methods.

However, the resin produced is liable to become impure due to the added emulsifier, and an operation such as salting out is required to take out the resin. Therefore, suspension polymerization is preferable because it is a simple method.

In the suspension polymerization method, a resin mixture is formed into a pearl-like shape by polymerizing a monomer mixture containing a low molecular weight polymer or copolymer in a suspended state together with a cross-linking agent. From the polymer or copolymer to the high molecular weight polymer or copolymer, including the cross-linking region component,
It can also be obtained in a preferred state of being uniformly mixed.

In suspension polymerization, water or an aqueous solvent 1
It is preferable to use 100 parts by weight or less (preferably 10 to 90 parts by weight) of the monomer for 100 parts by weight. As the dispersant that can be used, polyvinyl alcohol, partially saponified polyvinyl alcohol, calcium phosphate, etc. are used, and the amount is generally 0.05 to 1 part by weight with respect to 100 parts by weight of the aqueous solvent, although it varies depending on the amount of the monomer in the aqueous solvent. To be The polymerization temperature is suitably 50 to 95 ° C., but it should be appropriately selected depending on the initiator used and the target polymer. Any type of polymerization initiator may be used as long as it is insoluble or hardly soluble in water. For example, benzoyl peroxide, tert-butyl peroxyhexanoate, etc. are added in an amount of 0.5 with respect to 100 parts by weight of the monomer.
Used in 10 to 10 parts by weight.

Further, the vinyl resin used in the present invention is preferably a polymer crosslinked with a crosslinking monomer as exemplified below in order to achieve the object of the present invention.

Aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; diacrylate compounds linked by an alkyl chain such as ethylene glycol diacrylate, 1,3-butylene glycol diacrylate and 1,4-butanediol. Diacrylate,
1,5-Pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and the above compounds in which acrylate is replaced by methacrylate; diacrylates linked by an alkyl chain containing an ether bond Compounds, for example,
Diethylene glycol diacrylate, polyethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and the above compounds in which acrylate is replaced with methacrylate; Diacrylate compounds linked by a chain containing an aromatic group and an ether bond, for example, polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2 ，
2-bis (4-hydroxyphenyl) propane diacrylate, and those in which the acrylates of the above compounds are replaced by methacrylates; further, polyester type diacrylate compounds, for example, trade name MANDA (Nippon Kayaku) To be As the polyfunctional crosslinking agent, pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate,
Oligoester acrylates and those obtained by replacing the acrylates of the above compounds with methacrylates; triallyl cyanurate, triallyl trimellitate, and the like.

These cross-linking agents are used as the other monomer component 10
About 0 to 5 parts (about 0.03 to 5 parts)
It is preferable to use about 3 parts).

Among these crosslinkable monomers, those which are preferably used in the resin for toner from the viewpoints of fixing property and anti-offset property include an aromatic divinyl compound (particularly divinylbenzene), an aromatic group and an ether bond. Included are chain-linked diacrylate compounds.

Further, the binder resin used in the toner of the present invention is obtained by solution-mixing one or more kinds of polyolefin releasing agents in a polymerization solvent after polymerization.

By this method, the release agent can be well dispersed in the binder resin.

The polyolefin applicable to the present invention is, for example, a homopolymer of α-olefin such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene or a mixture of two or more α-olefins. Examples thereof include copolymers and polyolefin oxides, and these polyolefins may be vinyl graft-modified polyolefins.

The vinyl-based graft modified polyolefin is composed of the above-mentioned polyolefin component and modifying component, and the modifying component is grafted to the polyolefin component. As the modifying component, a vinyl-based monomer is used. For example, as the aliphatic vinyl-based monomer, methacrylic acid and methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, 2-ethylhexyl are used. Methacrylate, lauryl methacrylate, stearyl methacrylate, dodecyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate,
Methacrylates such as 2,2,2-trifluoroethyl methacrylate and glycidyl methacrylate, acrylic acid and methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, lauryl acrylate, stearyl acrylate, Dodecyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, 2-chloroethyl acrylate, 2-hydroxyethyl acrylate, cyclohexyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dibutylaminoethyl acrylate, 2-ethoxyacrylate, 1,4 -Acrylates such as butanediol diacrylate, maleic acid, fumaric acid, Conic acid, citraconic acid and monoethylmalate, diethylmalate, monopropylmalate, dipropylmalate, monobutylmalate, dibutylmalate, di-2-ethylhexyl fumarate, monoethylfumarate, diethylfumarate , Dibutyl fumarate, di-2-ethylhexyl fumarate, monoethyl itaconate, diethyl itaconate, monoethyl citracone, diethyl citracone, etc., and one or more of them are used at the same time. be able to.

As the aromatic vinyl monomer, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, p-ethylstyrene, pn-butylstyrene. , P-tert-butylstyrene, pn-dodecylstyrene, p-phenylstyrene, p-chlorostyrene, and the like, and one or more of these can be used at the same time.

As a method for graft modification, a conventionally known method can be used. For example, a graft-modified polyolefin is obtained by reacting the above-mentioned polyolefin with an aromatic vinyl monomer and an aliphatic vinyl monomer in a solution state or a molten state under heating in the atmosphere or under pressure in the presence of a radical initiator. The grafting with the aromatic vinyl monomer and the aliphatic vinyl monomer may be carried out both at the same time or individually.

The polyolefin used in the present invention preferably has a weight average molecular weight of 2 when measured by GPC.
000-30000, more preferably 5000-180
A low molecular weight of 00 is preferable.

In the magnetic toner of the present invention, the addition amount of the polyolefin to the binder resin is 10
The amount is preferably 0.1 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, based on 0 parts by weight. If the amount is less than 0.1 parts by weight, the effect on offset resistance cannot be exhibited, and if the amount is more than 20 parts by weight, the polyolefin particles precipitated in the binder resin become large and toner blocking is caused. The property is likely to deteriorate.

Further, as the metal-containing compound capable of reacting with the resin component of the present invention, those containing the following metal ions can be used. Suitable divalent metal ions include Ba ²⁺ , Mg ²⁺ ,
Ca ²⁺ , Hg ²⁺ , Sn ²⁺ , Pb ²⁺ , Fe ²⁺ , Co ²⁺ , N
i ²⁺ , Zn ²⁺ and the like. As trivalent ions, Al
³⁺ , Sc3 ⁺ , Fe3 ⁺ , Ce3 ⁺ , Ni3 ⁺ , Cr3 ⁺ , Y3 ⁺ and the like.

Among these metal compounds, the organometallic compound is excellent in compatibility and dispersibility with the resin composition, and the crosslinking by the metal compound progresses more uniformly in the polymer, which gives more excellent results.

Among the above organometallic compounds,
Those containing an organic compound rich in vaporization and sublimation as a ligand or a counter ion are useful. Among the organic compounds forming a ligand or counterion with a metal ion, those having the above-mentioned properties include salicylic acid; salicylic acid derivatives such as salicylamide, salicylamine, salicylaldehyde, acetylsalicylic acid, and ditertiarybutylsalicylic acid. Β-diketones such as acetylacetone and propionacetone; low molecular weight carboxylic acid salts such as acetate and propionic acid.

When a metal complex is used as the organometallic compound, it can also be used as a charge control agent for toner particles. As such a metal complex, there is an azo metal complex represented by the following general formula [I].

[0090]

[Chemical 1] [In the formula, M is a coordination center metal (for example, Sc with a coordination number of 6, T
i, V, Cr, Co, Ni, Mn, or Fe), Ar represents an aryl group (for example, a phenyl group or a naphthyl group), and may have a substituent. As the substituent in this case, a nitro group, a halogen group, a carboxyl group, an anilide group and an alkyl group having 1 to 18 carbon atoms,
There is an alkoxy group. X, X ′, Y and Y ′ are —O—,
-CO-, -NH- or -NR- (R is 1 to 4 carbon atoms.
Of Alkyl group) and A ⁺ represents hydrogen, sodium, potassium, ammonium or aliphatic ammonium. ] Next, the specific example of this metal complex is shown.

[0091]

[Chemical 2]

[0092]

[Chemical 3]

[0093]

[Chemical 4]

[0094]

[Chemical 5]

[0095]

[Chemical 6]

[0096]

[Chemical 7] Furthermore, an organic acid metal complex represented by the following general formula [II] as an organometallic compound also imparts a negative charging property, and can be used in the present invention.

[0097]

[Chemical 8] Next, specific examples of the complex are shown.

[0098]

[Chemical 9]

[0099]

[Chemical 10]

[0100]

[Chemical 11]

[0101]

[Chemical 12]

[0102]

[Chemical 13]

[0103]

[Chemical 14]

[0104]

[Chemical 15]

[0105]

[Chemical 16]

[0106]

[Chemical 17]

[0107]

[Chemical 18] These organometallic compounds may be used alone or in combination of two or more. The amount of the organometallic compound added to the toner particles varies depending on the type of the toner binder, whether or not the carrier is used in combination, the pigment for coloring the toner, and the reactivity of the metal complex with the binder, but the unreacted one. Including the above, the content is 0.01 to 20% by weight, preferably 0.1 to 10% by weight, based on 100% by weight of the binder.

When the above organometallic complex or organometallic salt is reacted with a binder resin during melt-kneading, it has excellent compatibility with the binder resin or dispersibility in the binder resin, and a stable charging property as a toner is obtained. There is.

In the present invention, it is possible to use an organometallic complex or an organometallic salt, which is one of the cross-linking components, as the charge control agent for the toner, but if necessary, other charge may be used. A combination of control agents can also be used. Examples of other charge control agents include conventionally known negative or positive charge control agents.

Charge control agents known in the art today include the following.

The following substances control the toner to be negatively charged.

For example, as the organometallic complex, a chelate compound is effective and there are the above-mentioned monoazo metal complex, acetylacetone metal complex, aromatic hydroxycarboxylic acid, aromatic dicarboxylic acid type metal complex. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

The following substances control the toner to be positively charged.

Modifications with nigrosine and aliphatic metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate,
And onium salts such as phosphonium salts and their lake pigments; lake pigments thereof; triphenylmethane dyes and lake pigments thereof (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannin) Acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyltin borate. And diorgano tin borates such as These may be used alone or in combination of two or more. Among these, charge control agents such as nigrosine and quaternary ammonium salts are particularly preferably used.

In the toner of the present invention, the charging stability,
In order to improve developability, fluidity and durability, it is preferable to add fine silica powder.

The fine silica powder used in the present invention is BE.
Specific surface area due to nitrogen adsorption measured by T method is 30 m ² / g
Those above (especially 50 to 400 m ² / g) give good results. The fine silica powder is used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the toner.

The fine silica powder used in the present invention contains, if necessary, a silicone varnish, a modified silicone varnish, a silicone oil, a modified silicone oil, a silane coupling agent, for the purpose of hydrophobizing or controlling the charging property.
It is preferably treated with a treating agent such as a silane coupling agent having a functional group or another organosilicon compound. It is also preferable to use the treating agents in combination.

Other additives include lubricants such as Teflon, zinc stearate and polyvinylidene fluoride (polyvinylidene fluoride being preferred among them); abrasives such as cerium oxide, silicon carbide and strontium titanate (among them, titanic acid). Strontium is preferred); fluidity-imparting agents such as titanium oxide and aluminum oxide (particularly hydrophobic ones are preferred); anti-caking agents; conductivity-imparting agents such as carbon black, zinc oxide, antimony oxide and tin oxide. To be Further, a small amount of white fine particles or black fine particles having a polarity opposite to that of the toner may be used as an additive as a developing property improver.

For the purpose of improving releasability at the time of heat roll fixing, wax-like substances such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, carnauba wax, sazol wax and paraffin wax are added to 100% by weight of binder resin. Addition of 0.5 to 10% by weight to the toner is also one of the preferable modes of the present invention.

Further, when the toner of the present invention is used as a two-component developer, it is used as a mixture with carrier powder. In this case, the mixing ratio of the toner and the carrier powder is 0.1 to 50% by weight as the toner concentration, preferably 0.1.
It is preferably 5 to 10% by weight, more preferably 3 to 5% by weight.

As the carrier that can be used in the present invention, known carriers can be used. Examples thereof include magnetic powders such as iron powders, ferrite powders, and nickel powders, and those whose surfaces are treated with a resin such as a fluorine-based resin, a vinyl-based resin, or a silicone-based resin.

The toner of the present invention can also be used as a magnetic toner whose toner particles contain a magnetic material. In this case, the magnetic material can also serve as a coloring agent. The magnetic material contained in the magnetic toner is magnetite,
Iron oxides such as hematite and ferrite; iron, cobalt,
Of metals such as nickel and these metals with metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium Alloys; including mixtures thereof.

These magnetic materials have an average particle size of 0.1 to 2
μm, preferably 0.1 to 0.5 μm. The amount contained in the toner is 20 to 200 parts by weight, and particularly preferably 40 to 150 parts by weight, based on 100 parts by weight of the resin component.

When applied with 10 K oersted, the magnetic characteristics are: coercive force 20 to 300 oersted, saturation magnetization 50 to 50.
It is preferably 200 emu / g and a residual magnetization of 2 to 20 emu / g.

Further, if desired, the desired additive and the toner of the present invention are thoroughly mixed by a mixer such as a Henschel mixer to obtain the toner for developing an electrostatic image of the present invention and a developer having an external additive. You can

The highly crosslinked high molecular weight component can be cut during the melt-kneading, but this can be satisfactorily carried out by kneading in the low-temperature melted state and giving a high shear to the kneaded product. The resin composition can be re-crosslinked with a metal-containing compound or the like by heat during melt-kneading.

For example, when an extruder is used, if the set temperature is set low and the shaft is configured to have a high shear, a high shear is applied when passing through the kneading section, and the molecular chain of the polymer chain is cut and discharged. During the reaction, a reaction with the metal compound occurs, and the resin composition is re-crosslinked.

The colorant that can be used in the toner of the present invention includes any suitable pigment or dye. As a toner colorant, for example, carbon black as a pigment,
Examples include aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, red iron oxide, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient for maintaining the optical density of the fixed image, and the amount added is 0.1 to 20 parts by weight, preferably 2 to 10 parts by weight, based on 100 parts by weight of the resin. In the case of dyes such as azo dyes, anthraquinone dyes, xanthene dyes, and methine dyes, the addition amount is 0.1 to 20 parts by weight, preferably 0.3 to 10 parts by weight, based on 100 parts by weight of the resin. .

A binder resin, an organometallic compound such as an organometallic complex or an organometallic complex, and a colorant (for example, a pigment, a dye or / and a magnetic substance) are required to prepare the toner for developing an electrostatic image according to the present invention. The charge control agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill according to the above, and melt-kneaded by using a heat kneader such as a heating roll, a kneader, or an extruder to make the resins compatible with each other. A toner can be obtained by dispersing or dissolving the organometallic compound and the colorant in the mixture, cooling and solidifying, and then pulverizing and classifying.

Next, the image forming method of the present invention will be described. The present invention is characterized in that an untransferred toner (waste toner) is reused, that is, an image is formed by utilizing a toner recycling system. That is,
After the transfer, the latent image carrier is cleaned to recover the toner on the latent image carrier, and the recovered toner is reused in the developing process.

FIG. 1 shows an example of an image forming apparatus applicable to the image forming method of the present invention. However, the exposure system, the transport system, the fixing device, etc. necessary for image formation are omitted.

In this image forming apparatus, first, the surface of the latent image carrier (photosensitive drum) 2 is uniformly charged by the corona discharge of the primary charger 1, and then the latent image carrier 2 is exposed by the exposure system (omitted). Imagewise exposure is performed to form a latent image. Next, the toner contained in the developing device 3 flies onto the latent image carrier 2 by the developing bias applied to the developing sleeve and the blade, and the latent image is developed to form a toner image.
The amount of toner in the developing device 3 is kept constant by consuming toner and replenishing the toner from the replenishing hopper 4 as needed. Further, if necessary, the pre-transfer charger 5 removes excess charges on the latent image carrier 2, and then the transfer charger 6 to which a bias is applied transfers the toner image to a transfer material (omitted) to apply the bias. The transfer material is separated from the latent image carrier 2 by the added separation charging device 7 and is subjected to heat roll fixing by a fixing device (omitted) to form a fixed image. On the other hand, after the completion of the transfer process, the toner remaining on the latent image carrier 2 is scraped off by the cleaning blade of the cleaner 8 and collected. The cleaned latent image carrier 2 is used for the next copying, but the toner collected by the cleaner 8 is returned to the developing step and reused by the waste toner delivery pipe 9 provided with a conveying screw.

Although the waste toner is returned to the toner replenishing hopper 4 in FIG. 1, there is no problem even if the system is such that the waste toner is returned directly to the developing device 3.

[0134]

The present invention will be described in detail below with reference to specific examples, but the present invention is not limited thereto. All parts in the following formulations are parts by weight.

Synthesis Example 1 Styrene 70 parts n-Butyl acrylate 30 parts Di-tert-butyl peroxide 1 part The above materials were added dropwise to 200 parts of heated toluene over 4 hours. Further, solution polymerization was completed under toluene reflux, and toluene was removed while heating (120 ° C.) under reduced pressure to obtain a resin.

Resin 30 parts Styrene 44.3 parts n-Butyl acrylate 20 parts Monobutyl maleate 5 parts Divinylbenzene 0.7 parts Benzoyl peroxide 1.2 parts Polyvinyl alcohol partially saponified product 0.2 to the above mixture.
170 parts of water having parts dissolved therein was added and vigorously stirred to obtain a suspension dispersion liquid. Further, 30 parts of water was added, and the above suspension dispersion was added to a reactor purged with nitrogen to carry out a suspension polymerization reaction at a reaction temperature of 80 ° C. for 8 hours. After the reaction was completed, it was washed with water, dehydrated and dried to obtain a resin composition A.

(Synthesis Example 2) Styrene 72 parts N-butyl acrylate 28 parts Di-tert-butyl peroxide 1 part Using the above materials, solution polymerization was carried out in the same manner as in Synthesis Example 1 to obtain a resin.

The above resin 30 parts Styrene 41.6 parts n-Butyl acrylate 21 parts Monobutyl maleate 7 parts Divinylbenzene 0.4 parts Benzoyl peroxide 1.3 parts Di-tert-butylperoxy-2-0.8 Part Ethyl hexanoate Using the above materials, suspension polymerization was carried out in the same manner as in Synthesis Example 1,
Resin composition B was obtained.

(Synthesis Example 3) Styrene 78 parts 2-Ethylhexyl acrylate 17 parts Methacrylic acid 5 parts Di-tert-butyl peroxide 2 parts The above compound was placed in 200 parts of cumene heated to the reflux temperature for 4 hours. Dropped. Under cumene reflux (140
Solution polymerization was completed at ~ 160 ° C) and the cumene was removed.

30 parts of the copolymer thus obtained was dissolved in the following monomer mixture to give a mixed solution.

Styrene 52 parts n-Butyl acrylate 14 parts Monobutyl maleate 3.5 parts Divinylbenzene 0.5 parts Azobisvaleronitrile 1 part Suspension polymerization is carried out in the same manner as in Synthesis Example 1 using the above materials and a resin composition. Item C was obtained.

(Synthesis Example 4) Styrene 100 parts Di-tert-butyl peroxide 3 parts The above components were subjected to solution polymerization in the same manner as in Synthesis Example 1 to obtain a copolymer.

Copolymer 35 parts Styrene 31 parts n-Butyl acrylate 22 parts Monobutyl maleate 12 parts Divinylbenzene 0.5 parts Azobisvaleronitrile 0.8 parts The above components were suspended by the same means as in Synthesis Example 1. Turbid polymerization was performed to obtain a resin composition D.

(Comparative Synthesis Example 1) In Synthesis Example 1, the ratio of materials in suspension polymerization was: resin obtained by solution polymerization 60 parts styrene 22.2 parts n-butyl acrylate 15 parts monobutyl maleate 2.1 parts divinyl A resin composition E was obtained in the same manner as in Synthesis Example 1 except that 0.7 part of benzene and 1.2 parts of benzoyl peroxide were used.

COMPARATIVE SYNTHESIS EXAMPLE 2 Styrene 78 parts n-Butyl acrylate 20 parts Monobutyl maleate 3 parts Divinylbenzene 0.5 parts Di-tert-butylperoxy-2-0.9 parts Ethylhexanoate In the same manner as in Synthesis Example 1, a resin (high molecular weight type) was obtained by suspension polymerization.

Styrene 75 parts n-butyl acrylate 20 parts n-butyl maleate 5 parts Di-tert-butyl peroxide 0.7 parts The above materials were added dropwise to 200 parts of heated toluene over 4 hours. Polymerization was further completed under reflux of toluene, and the high-molecular-weight resin was added to the reaction mixture at 9 and the main polymer was added to the reaction mixture, and the mixture was stirred well and then heated under reduced pressure (120
Toluene was removed while the temperature was kept at 0 ° C.) to obtain a resin composition F.

Example 1 100 parts of resin composition A, 80 parts of magnetite, 2 parts of nigrosine and 3 parts of low molecular weight polypropylene were weighed,
After pre-mixing these with a Henschel mixer, 120
Melt kneading was carried out at 2 ° C by a twin-screw kneading extruder. After the mixture was allowed to cool, it was pulverized with a fine pulverizer using a jet stream and further classified with an air classifier to obtain a black fine powder (toner) having a weight average particle diameter of 8.55 μm.

To 100 parts of the above toner, 0.6 part of positively charged silica fine powder treated with amino-modified silicone oil was added and dry mixed to obtain a developer.

The image evaluation was performed on this developer using a copying machine NP5060 reversal developing machine (using an amorphous silicon photoconductor) manufactured by Canon which was modified as shown in FIG.

The results of image evaluation were good, and there was no problem in continuous copying using a recycling system. Further, after outputting 100,000 sheets, when the toner consumption amount was examined using an A4 size original having an image area ratio of 6%, it was 0.046 g / sheet. Table 1 shows the molecular weight distribution of the resin component, and Table 2 shows the evaluation results. However, GPC (High Performance Liquid Chromatograph 150C manufactured by Waters) was used to measure the molecular weight distribution of the resin component, and the column was Shodex GPC KF-80 manufactured by Showa Denko KK.
1, 802, 803, 804, 805, 806, 80
A combination of 7,800P was used. The sample concentration was adjusted so that the resin component was 5 mg / ml.

Here, the fixability is determined by the low temperature and low humidity environment (15
The evaluation machine was allowed to stand overnight at ℃, 10%), and the evaluation machine and the fixing device inside thereof were completely acclimatized to the low temperature and low humidity environment, and 200 consecutive copy images were taken. The 200th sheet was used for evaluation of fixability. The fixing property was evaluated by rubbing the image with sillbon paper 10 times in a reciprocating manner under a load of about 100 g, and peeling of the image was evaluated by a reduction rate (%) of reflection density.

For the offset property, the cleaning mechanism of the fixing roller was removed, and the number of copies for which the image was soiled or the roller was soiled was evaluated by the number of copy resistant sheets.

The blocking property is about 1 g of toner of about 10 g.
It was examined by changing the degree of cohesion when placed in a 00 cc poly cup and left at 50 ° C. for 1 day. The aggregation degree was measured by a powder tester manufactured by Hosokawa Micron. The indicator of blocking property was the difference in the degree of aggregation between the product left at room temperature and the product left at 50 ° C./day.

Example 2 A toner having a weight average particle diameter of 8.71 μm was obtained by carrying out toner formation in the same manner as in Example 1 except that B was used instead of the resin composition A in Example 1. . The image evaluation results were good as shown in Table 2.

Example 3 A toner was prepared in the same manner as in Example 1 except that C was used instead of the resin composition A and tetrabutylammonium tetrafluoroborate was used instead of nigrosine. A developer having an average particle size of 8.47 μm was obtained. The image evaluation results are shown in Table 2.

Example 4 The weight average particle diameter was 8 in the same manner as in Example 1 except that D instead of the resin composition A and an external additive were added to silica to make 2 parts of strontium titanate. .67μ
m developer was obtained. The results of image evaluation are shown in Table 2.

Example 5 In the same manner as in Example 1 except that the chromium complex of acetylsalicylic acid was replaced with negatively charged silica obtained by subjecting silica to a hydrophobic treatment, instead of nigrosine.
A developer having a weight average particle diameter of 9.21 μm was obtained. Evaluation is NP
5060 was carried out by a regular developing method. The image evaluation results are shown in Table 2.

Example 6 A toner having a weight average particle diameter of 8.47 μm was obtained in the same manner as in Example 1 except that 5 parts of carbon black was used instead of magnetite. Image evaluation is
The developing device was changed to that for non-magnetic toner, and a ferrite carrier (particle size: 80 μm) whose surface was coated with a fluororesin was used as the carrier, and the mixing ratio of the toner to the carrier was 8% by weight. The evaluation results are shown in Table 2.

Example 7 The same developer as in Example 1 was used, but the image evaluation was carried out in such a structure that untransferred toner (waste toner) was returned directly to the developing device. The result was good as in the case of Example 1.

Comparative Example 1 A developer was obtained in the same manner as in Example 1 except that E was used instead of the resin composition A in Example 1. In this case, since the molecular weight of the high molecular weight is small, the result of image evaluation shows that the anti-offset property is poor as shown in Table 2, and the deterioration of the image quality and the image density as the evaluation progresses even in the reuse system. It was remarkable. After printing 200,000 sheets, the developer in the developing device was collected and observed by SEM. As a result, many peeled surfaces were observed.

Comparative Example 2 A developer was obtained in the same manner as in Example 1 except that F was used instead of the resin composition A. The resin used in this developer had a low content of low-molecular weight components, and thus was inferior in fixability and pulverizability at the time of production as compared with the case of Example 1. The evaluation results are shown in Table 2.

Comparative Example 3 A developer was manufactured and evaluated in the same manner as in Example 1 except that the untransferred toner (waste toner) was not reused in the image evaluation.

The image quality and the like did not occur at all from the beginning, but the toner consumption amount was 0.054 g / sheet, which was an increase of 17% as compared with the case of the first embodiment. Table 2 shows the image evaluation results.

[0164]

[Table 1]

[0165]

[Table 2] (Synthesis example 5) Styrene 75 parts n-butyl acrylate 25 parts Monobutyl maleate 5 parts Divinylbenzene 0.7 parts Benzoyl peroxide 1.3 parts The above mixture is mixed with partially saponified polyvinyl alcohol.
Two parts were added to 170 parts of dissolved water and vigorously stirred to give a suspension dispersion. Further, 30 parts of water was added, and the above suspension dispersion was added to a reactor purged with nitrogen, and the reaction temperature was 90 ° C.
The suspension polymerization reaction was carried out for 10 hours. After completion of the reaction, wash with water,
A high molecular weight polymer was obtained by dehydration and drying.

Next, xylene 400 was added to the above-mentioned polymerization apparatus.
Parts, stirred under a nitrogen gas stream, heated to maintain 90 ° C., a mixture of 80 parts of styrene, 20 parts of n-butyl acrylate and 2 parts of di-tert-butyl peroxide was used with a continuous dropping device. For 6 hours to complete the polymerization.
A polymerization solution of a resin which is a low molecular weight polymer was obtained.

In the above polymerization solution (containing 30 parts of low molecular weight polymer), 70 parts of high molecular weight polymer and 4 parts of low molecular weight polypropylene (weight average molecular weight = about 10,000) were added to 100 parts of 100 parts.
The solution was mixed while sufficiently stirring at 4 ° C. for about 4 hours, and then the solvent was removed to obtain a final resin composition G.

(Synthesis Example 6) The same procedure as in Synthesis Example 5 was repeated except that a styrene / butylene acrylate-modified polyethylene release agent (weight average molecular weight = 7.0 × 10 ³ ) was used as the release agent. Thus, a resin composition H was obtained.

(Synthesis Example 7) Styrene 78 parts 2-Ethylhexyl acrylate 18.5 parts Monobutyl maleate 3.5 parts Divinylbenzene 0.5 parts Azobisvaleronitrile 1 part As in Synthesis Example 5 using the above materials. Suspension polymerization,
A high molecular weight polymer was obtained. Next, styrene 76 parts 2-ethylhexyl acrylate 18 parts Methacrylic acid 6 parts Di-tert-butyl peroxide 1.5 parts The above materials were placed in 400 parts of xylene, and solution polymerization was carried out in the same manner as in Synthesis Example 5, A low molecular weight polymer was obtained.

In a polymerization solution containing 30 parts of a low molecular weight polymer,
70 parts of high molecular weight polymer and 4 parts of graft-modified polyethylene release agent (weight average molecular weight = about 8.0 × 10 ³ ) were added at 95 ° C.
After polymerizing the solution for 5 hours with sufficient stirring,
A resin composition I was obtained by removing the solvent.

(Comparative Synthesis Example 3) In Synthesis Example 5, the ratio of materials mixed in a solution was changed to 70 parts of low molecular weight polymer, 30 parts of high molecular weight polymer and 4 parts of low molecular weight polypropylene (weight average molecular weight = about 10,000). A resin composition J was obtained in the same manner as in Synthesis Example 5 except that it was changed.

COMPARATIVE SYNTHESIS EXAMPLE 4 In Synthesis Example 5, the ratio of materials mixed in a solution was 10 parts of low molecular weight polymer, 90 parts of high molecular weight polymer and 4 parts of low molecular weight polypropylene (weight average molecular weight = about 10,000). A resin composition K was obtained in the same manner as in Synthesis Example 5 except that it was changed.

(Comparative Synthesis Example 5) A resin composition L was obtained in the same manner as in Synthesis Example 5, except that the releasing agent component was not added during the solution mixing.

Comparative Synthetic Example 6 Styrene 80 parts n-Butyl acrylate 20 parts Divinylbenzene 0.5 part Azobisvaleronitrile 0.8 part Suspension polymerization was carried out in the same manner as in Synthesis Example 5 using the above materials,
A high molecular weight polymer was obtained. Next, 400 parts of xylene was placed in the same polymerization apparatus, and the temperature was raised to 90 ° C. while stirring under a nitrogen gas stream, and 100 parts of styrene and 3 parts of di-tert-butyl peroxide were added using a continuous dropping device using 6 parts. Polymerization was performed by dropping over time to obtain a polymerization solution containing a low molecular weight polymer.

In the above polymerization solution (containing 35 parts of low molecular weight polymer), 65 parts of high molecular weight polymer was added at 100 ° C. for about 3.5.
The solution was mixed with sufficient stirring over time, and then the solvent was removed to obtain a resin composition M.

Example 8 100 parts of Resin Composition G, 80 parts of magnetite and 2 parts of nigrosine were weighed out, pre-mixed with a Henschel mixer, and melt-kneaded at 120 ° C. with a twin-screw kneading extruder. It was After the mixture was allowed to cool, it was pulverized with a fine pulverizer using a jet stream and further classified with an air classifier to obtain a black fine powder (toner) having a weight average particle diameter of 8.40 μm.

To 100 parts of the above-mentioned toner, 0.6 part of positively charged silica fine powder treated with amino-modified silicone oil was added and dry mixed to obtain a developer.

Image evaluation was performed on this developer using a copying machine NP5060 reversal developing machine (using an amorphous silicon photoreceptor) manufactured by Canon, which was modified as shown in FIG.

The results of image evaluation were good, and there was no problem in continuous copying using a recycling system. Furthermore, when an amount of toner consumption was examined using an A4 size original having an image area ratio of 6% after printing 200,000 sheets, it was 0.047 g / sheet. The GPC measurement result of the resin component is shown in Table 3, and the image evaluation result is shown in Table 4.

Example 9 A toner having a weight average particle diameter of 8.65 μm was obtained in the same manner as in Example 8 except that H was used instead of the resin composition G in Example 8. It was The results of image evaluation were good as shown in Table 4.

Example 10 A toner was prepared in the same manner as in Example 8 except that I was used in place of the resin composition G and tetrabutylammonium tetrafluoroborate was used in place of nigrosine. A developer having a weight average particle diameter of 8.38 μm was obtained. The image evaluation results are shown in Table 4.

Example 11 In the same manner as in Example 8 except that instead of nigrosine, the chromium complex of acetylsalicylic acid was changed to negatively charged silica obtained by subjecting silica to a hydrophobic treatment.
A developer having a weight average particle diameter of 9.30 μm was obtained. Evaluation is NP
5060 was carried out by a regular developing method. The image evaluation results are shown in Table 4.

Example 12 A toner having a weight average particle diameter of 8.51 μm was obtained in the same manner as in Example 8 except that 5 parts of carbon black was used instead of magnetite. Image evaluation is
The developing unit was changed to that for non-magnetic toner, and a ferrite carrier (particle size: about 80 μm) whose surface was coated with a fluororesin was used as the carrier, and the mixing ratio of the toner to the carrier was 8% by weight. The evaluation results are shown in Table 4.

Example 13 The same developer as in Example 8 was used, but the image evaluation was carried out in such a configuration that untransferred toner (waste toner) was returned directly to the developing device. The result was good as in the case of Example 8.

Comparative Example 4 The weight average particle diameter is 8.45 μm in the same manner as in Example 8 except that J is used instead of the resin composition G in Example 8.
m developer was obtained. In this case, since the high molecular weight of the resin component is small, the result of image evaluation shows that the anti-offset property is poor as shown in Table 4, and also in the reuse system, as the evaluation progresses, the image quality and image density The decrease was remarkable. After printing 200,000 sheets, the developer in the developing device was collected and observed by SEM. As a result, many peeled surfaces were observed.

Comparative Example 5 The weight average particle diameter is 8.50 μm in the same manner as in Example 8 except that K is used instead of the resin composition G.
m developer was obtained. The content of the low molecular weight component of the resin component was small in this developer, and the fixability and the pulverizability at the time of production were inferior to those in Example 8. The evaluation results are shown in Table 4.

Comparative Example 6 A developer was obtained in the same manner as in Example 8 except that L was used instead of the resin composition G in Example 8. In this developer, the release agent component is not internally added to the resin used. Therefore, as a result of the image evaluation, the offset resistance is remarkably inferior and becomes remarkable as the evaluation progresses, and when the fixing roller is viewed at 10,000 sheets, it is black, and the backside of the fixed image is also extremely dirty. The evaluation was unbearable, so the evaluation was stopped at this point.

Comparative Example 7 In Example 8, M was used in place of the resin composition G,
A developer having a weight average particle diameter of 8.45 μm was obtained in the same manner as in Example 8 except that 3 parts of low molecular weight polypropylene was further added. The image evaluation results were generally good as shown in Table 4, but a slight offset was observed when the image at the time of 200,000 sheets was compared with Example 8.

Comparative Example 8 A developer was produced and evaluated in the same manner as in Example 8 except that the untransferred toner (waste toner) was not reused in the image evaluation.

Although there was no problem in image quality from beginning to end, the toner consumption amount was 0.056 g / sheet, which was an increase of 19% as compared with the case of Example 8. Table 4 shows the image evaluation results.

[0191]

[Table 3]

[0192]

[Table 4] (Synthesis example 8) Styrene 85 parts n-butyl acrylate 15 parts Di-tert-butyl peroxide 5 parts The above components were added dropwise to 400 parts of cumene heated to the reflux temperature over 5 hours. In addition, under cumene reflux (140
Solution polymerization was completed at ~ 160 ° C), cumene was removed, and a resin was obtained.

Resin 30 parts Styrene 44.6 parts n-Butyl acrylate 18 parts Monobutyl maleate 7 parts Divinylbenzene 0.35 parts Benzoyl peroxide 1.2 parts Di-tert-butylperoxy-2-0.6 Part Ethyl hexanoate 170 parts of water in which 1 part of partially saponified polyvinyl alcohol was dissolved was added to the above mixed solution, and the mixture was vigorously stirred to give a suspension dispersion. Further, 30 parts of water was added, and the suspension dispersion was added to a reactor purged with nitrogen, and a suspension polymerization reaction was carried out at a reaction temperature of 80 ° C. for 9 hours. After the reaction was completed, it was washed with water, dehydrated and dried to obtain a resin composition N.

Synthesis Example 9 Styrene 70 parts n-Butyl acrylate 30 parts Di-tert-butyl peroxide 1 part The above materials were added dropwise to 300 parts of heated toluene over 4 hours. Further, solution polymerization was completed under toluene reflux, and toluene was removed while heating (120 ° C.) under reduced pressure to obtain a resin.

Resin 30 parts Styrene 41.6 parts n-Butyl acrylate 18 parts Monobutyl maleate 10 parts Divinylbenzene 0.4 parts Benzoyl peroxide 1.5 parts Suspension using the above materials in the same manner as in Synthesis Example 8. Polymerize,
Resin composition O was obtained.

(Synthesis Example 10) Styrene 80 parts 2-Ethylhexyl acrylate 17 parts Methacrylic acid 3 parts Di-tert-butyl peroxide 2.2 parts The above components were subjected to solution polymerization under the same conditions as in Synthesis Example 8. A low molecular weight polymer was obtained.

The low molecular weight polymer 35 parts Styrene 39.3 parts n-Butyl acrylate 15 parts Monobutyl maleate 10 parts Divinylbenzene 0.7 parts Azobisvaleronitrile 1.2 parts Using Synthesis Example 8 and the above materials. Similarly, suspension polymerization is performed.
A resin composition P was obtained.

(Synthesis Example 11) Styrene 100 parts Di-tert-butyl peroxide 3 parts The above components were subjected to solution polymerization in the same manner as in Synthesis Example 8 to obtain a copolymer.

Copolymer 30 parts Styrene 34 parts n-Butyl acrylate 23 parts Monobutyl maleate 13 parts Divinylbenzene 0.5 parts Azobisvaleronitrile 0.8 parts The above components were suspended by the same means as in Synthesis Example 8. Turbid polymerization was carried out to obtain a resin composition Q.

(Comparative Synthesis Example 7) In Synthesis Example 8, the material ratio in suspension polymerization was: resin obtained by solution polymerization 60 parts styrene 19.5 parts n-butyl acrylate 10 parts monobutyl maleate 10 parts divinylbenzene 0 0.5 part Benzoyl peroxide A resin composition R was obtained in the same manner as in Synthesis Example 8 except that 1.5 parts was used.

Comparative Synthesis Example 8 Styrene 74 parts n-Butyl acrylate 20 parts Monobutyl maleate 5 parts Divinylbenzene 1 part tert-Butylperoxyhexanoate 0.8 parts Using the above materials, Synthesis Example 8 and In the same manner, a resin (high molecular weight product) was obtained by suspension polymerization.

Styrene 75 parts n-Butyl acrylate 25 parts Di-tert-butyl peroxide 0.5 parts The above materials were added dropwise to 200 parts of heated toluene over 4 hours. Further, the polymerization was completed under reflux of toluene, and 90 parts of the high molecular weight polymer was dissolved and mixed in a polymerization solution containing 10 parts of the present polymer at 100 ° C. for about 4 hours while sufficiently stirring. After that, the solvent was removed to obtain a resin composition S.

Comparative Synthesis Example 9 A resin was prepared in the same manner as in Synthesis Example 8 except that the amount of n-butyl acrylate was changed to 25 parts and monobutyl maleate was not added during suspension polymerization in Synthesis Example 8. A composition T was obtained.

Example 13 100 parts of Resin Composition N, 85 parts of magnetite, 2 parts of Exemplified Complex [II] -1 and 3 parts of low molecular weight polypropylene.
Parts were weighed, pre-mixed with a Henschel mixer, and then melt-kneaded at 120 ° C. with a twin-screw kneading extruder. After the mixture was allowed to cool, it was pulverized with a fine pulverizer using a jet stream and further classified with an air classifier to obtain a black fine powder (toner) having a weight average particle diameter of 9.32 μm.

To 100 parts of the above-mentioned toner, 0.5 part of the negatively charged silica fine powder subjected to the hydrophobic treatment was added and dry mixed to obtain a developer.

Image evaluation was performed on this developer with a copying machine NP5060 (using an amorphous silicon photoconductor) manufactured by Canon, which was modified as shown in FIG.

The image evaluation results were good, and there was no problem in continuous copying using the recycling system. Further, after outputting 200,000 sheets, when the toner consumption amount was examined using an A4 size original having an image area ratio of 6%, it was 0.048 g / sheet. The molecular weight distribution of the resin component of the toner is shown in Table 5, and the image evaluation results are shown in Table 6.

Example 14 A toner having a weight average particle size of 9.40 μm was obtained in the same manner as in Example 13, except that O was used instead of the resin composition N in Example 13. It was The image evaluation results were good as shown in Table 6.

Example 15 The same as Example 13 except that P was used in place of the resin composition N and Exemplified complex [I] -2 was used in place of Exemplified complex [II] -1. The toner was converted to toner to obtain a developer having a weight average particle diameter of 9.25 μm. The results of image evaluation are shown in Table 6.

Example 16 In Example 13, instead of the resin composition N, Q was added, 1 part each of Exemplified Complex [II] -1 and Exemplified Complex [I] -2, and titanium was added by adding an external additive to silica. A developer having a weight average particle diameter of 9.05 μm was obtained in the same manner as in Example 13 except that 2 parts of strontium acid was used. The results of image evaluation are shown in Table 6.

Example 17 In Example 13, a positively chargeable silica was prepared in which 3 parts of acetylacetone cobalt (III) and 2 parts of nigrosine were used in place of the exemplified complex [II] -1, and the amino-modified silicone oil was further treated. Example 13 except for changing
A developer having a weight average particle diameter of 8.73 μm was obtained in the same manner as in. Image evaluation was performed by reversal development of NP5060.
The results of image evaluation are shown in Table 6.

Example 18 A toner having a weight average particle diameter of 9.10 μm was obtained in the same manner as in Example 13 except that 5 parts of carbon black was used instead of magnetite. In the image evaluation, the developing device was changed to that for non-magnetic toner, a ferrite carrier (particle size: 80 μm) whose surface was coated with a fluororesin was used as a carrier, and the mixing ratio of the toner to the carrier was 8% by weight. The evaluation results are shown in Table 6.

Example 19 The same developer as in Example 13 was used, but the image evaluation was carried out in such a structure that untransferred toner (waste toner) was returned directly to the developing device. The result was good as in the case of Example 13.

Comparative Example 9 A developer was obtained in the same manner as in Example 13 except that R was used instead of the resin composition N. Table 5
As shown in Table 1, since the resin composition R has a small molecular weight on the high molecular weight side, the result of image evaluation shows that the offset resistance is poor as shown in Table 6 and the evaluation is made even in continuous copying in a reuse system. As the number of sheets proceeded, the image quality and the image density decreased remarkably. After 200,000 sheets were printed, the developer in the developing device was collected and observed by SEM. As a result, many particles were broken due to mechanical damage.

Comparative Example 10 A developer was obtained in the same manner as in Example 13 except that S was used instead of the resin composition N. Table 5
As described above, this resin has a small Mw / Mn and a small amount of low molecular weight components, and therefore, compared with the case of Example 13,
The fixability and the pulverizability during manufacturing were poor. The evaluation results are as shown in Table 6.

Comparative Example 11 A developer was obtained in the same manner as in Example 13 except that T was used instead of the resin composition N. The resin composition T does not contain an acid component. Therefore, not only the fixability of the developer is deteriorated, but also re-crosslinking (metal crosslinking) of the highly crosslinked high molecular weight component of the resin cut during melt-kneading is not performed, so that the strength of the developer cannot be sufficiently obtained. . Therefore, in continuous copying in the reuse system,
The developability deteriorated. The results are shown in Table 6.

Comparative Example 12 A developer was manufactured and evaluated in the same manner as in Example 13 except that the untransferred toner (waste toner) was not reused in the image evaluation.

[0218] Although the image quality and the like did not occur at all from beginning to end, the toner consumption amount was 0.056 g / sheet, which was a 17% increase compared with the case of Example 13. Table 6 shows the image evaluation results.

[0219]

[Table 5]

[0220]

[Table 6]

[0221]

In the toner for developing an electrostatic image of the present invention, the problems associated with the conventional toners are remarkably improved, the anti-offset property and the anti-blocking property are excellent, and the low temperature fixing property and the developing property are also excellent. The result can be given. Furthermore, when used in a system that collects waste toner and reuses it in the development process, even when copying a large number of sheets for a long period of time, a high reflection image density is maintained from beginning to end, and fog and toner scattering do not occur. An image is obtained.
Further, since the waste toner can be reused, the toner can be effectively used, and a high reflection image density can be obtained with a small toner consumption amount.

That is, the high molecular weight component in the toner of the present invention not only excels in offset resistance and filming resistance, but also makes the strength of the toner strong. As a result, in the system in which the waste toner is reused, the untransferred toner (waste toner) is not damaged by the mechanical shock in the cleaner part, so that the waste toner has the same developability as the replenishment toner. Can have.

In addition, since Mw / Mn is as wide as 10 or more in the average molecular weight, the resin has a wide distribution from low molecular weight to high molecular weight. Therefore, the fixability and the pulverizability are also improved, and it becomes possible to obtain a high-quality image for a long period of time.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic sectional view of a developing device used for image formation in Examples and Comparative Examples.

[Explanation of symbols] 1 Primary charger 2 Latent image carrier (photosensitive drum) 3 developer 4 Toner supply hopper 5 Pre-transfer charger 6 Transfer charger 7 Separation charger 8 cleaner 9 Waste toner delivery pipe with a conveying screw

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Unno 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) Reference JP-A-2-110572 (JP, A) JP-A-63 -217358 (JP, A) JP 62-119549 (JP, A) JP 62-195683 (JP, A) JP 3-80260 (JP, A) JP 4-188153 (JP, A) ) JP-A-4-226473 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 9/08-9/087

Claims (3)

(57) [Claims] 1. A latent image on a latent image carrier is developed to form a toner image, the formed toner image is transferred from the latent image carrier to a transfer material, and the latent image carrier after the transfer is cleaned. A toner for electrostatic image development used in an image forming method in which the toner on the latent image bearing member is collected, and the collected toner is supplied to the developing section to be used in the developing step. Gel permeation chromatography (GPC) of resin components
Has two or more peaks or shoulders and one peak or shoulder in the region of molecular weight of 400,000 or more.
Furthermore, in the average molecular weight calculated by GPC, the weight average molecular weight (Mw) and the number average molecular weight (Mn)
Ratio Mw / Mn of 40 to 46 . 2. A latent image on the latent image carrier is developed to form a toner image, the formed toner image is transferred from the latent image carrier to a transfer material, and the latent image carrier after the transfer is cleaned. A toner for electrostatic image development used in an image forming method in which the toner on the latent image bearing member is collected, and the collected toner is supplied to the developing section to be used in the developing step. Gel permeation chromatography (GPC) of resin components
Has two or more peaks or shoulders and one peak or shoulder in the region of molecular weight of 400,000 or more.
Furthermore, in the average molecular weight calculated by GPC, the weight average molecular weight (Mw) and the number average molecular weight (Mn)
The toner for developing an electrostatic charge image has a ratio Mw / Mn of 41 to 47 , and is obtained by solvent-mixing at least one or more polyolefin release agents and removing the solvent. 3. A latent image on the latent image carrier is developed to form a toner image, the formed toner image is transferred from the latent image carrier to a transfer material, and the latent image carrier after the transfer is cleaned. A toner for electrostatic charge image development used in an image forming method in which the toner on the latent image carrier is collected, and the collected toner is supplied to the developing section to be used in the developing step. The binder resin contains an agent and a metal compound, and is a polymer having a carboxylic acid-containing monomer and another copolymerizable monomer as constituent components, and the molecular weight distribution of the resin component by gel permeation chromatography (GPC). Has two or more peaks or shoulders, and has one peak or shoulder in the region of molecular weight of 500,000 or more, and further, in the average molecular weight calculated by GPC, the weight average molecular weight The toner for developing an electrostatic image and a ratio Mw / Mn of Mw) to the number average molecular weight (Mn) of 52 to 63.