JP2003241411A - Method and device for forming image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming an image and an image forming device so as to provide an electrophotographic image with sufficiently high picture quality even when a toner having a controlled shape factor and distribution of the grain size and having a decreased particle size is used. <P>SOLUTION: The method for forming an image is carried out by developing a latent image formed on the following electrophotographic photoreceptor with a developer which uses a toner having ≤16% coefficient of variation in the shape factor of the toner particles. The electrophotographic photoreceptor has a surface layer containing a binder resin and a polymer produced from a compound having a polymerizable functional group. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method and an image forming apparatus used for electrophotographic copying machines, printers and the like.

[0002]

2. Description of the Related Art In recent years, an organic photoconductor containing an organic photoconductive substance has been most widely used as an electrophotographic photoconductor. Organic photoconductors are advantageous over other photoconductors because it is easy to develop materials for various exposure light sources from visible light to infrared light, materials that do not cause environmental pollution can be selected, and manufacturing costs are low. However, the mechanical strength is weak, and the surface of the photoreceptor is deteriorated or scratched when a large number of sheets are copied or printed.

In addition, focusing on the electrophotographic process, latent image forming methods are roughly classified into analog image forming using a halogen lamp as a light source and digital image forming using an LED or a laser as a light source. Recently, as a printer for a personal computer, and also in a normal copying machine, a digital latent image forming method is rapidly becoming the mainstream because of the ease of image processing and the ease of development to a multi-function peripheral.

In digital image formation, not only copying, but also the use of creating original images has increased,
Digital electrophotographic image formation tends to require higher image quality.

One of the techniques for improving the image quality is to control the particle size distribution of a toner using a polymerized toner and to make the toner smaller. However, since the toner of the polymerized toner has a spherical shape, the toner is attached to the photoreceptor. This tends to cause a problem that the adhesion becomes large, the transferability of the toner from the photoconductor to the recording paper is deteriorated, and the cleaning property is deteriorated. When the transferability is lowered, not only the image density is lowered, but also an image defect called "middle void" in which a blank portion is generated in a part of a character image or the like is likely to occur. Further, when the cleaning property is deteriorated, the residual toner on the photoconductor is not sufficiently removed, and so-called "toner slipping" occurs, which results in toner filming.
Image defects such as "white spots" are likely to occur. Further, when the frictional resistance between the photoconductor and the cleaning blade becomes large, an abnormal sound called "blade squeal" is generated, and at the same time, "blade winding (blade reversal phenomenon)" tends to occur.

As an approach for solving the above-mentioned problems, fine particles are contained in the surface of the photoconductor in a low surface energy state to bring the surface into a low surface energy state to reduce the adhesive force of the toner on the surface of the photoconductor. Techniques such as improving transferability and reducing frictional force with a blade have been studied. For example, JP-A-5-181291 reports that a photosensitive layer contains fine particles of alkylsilsesquioxane resin. However, the alkyl silsesquioxane resin fine particles have hygroscopicity, and in a high humidity environment, the wettability of the surface of the photoconductor becomes large, the resolution decreases and the frictional force with the blade increases, and blade squeal occurs. There is such a problem. On the other hand, JP-A-63-5
Japanese Patent No. 6658 reports a photosensitive layer containing a fluororesin powder such as tetrafluoropolyethylene in the photosensitive layer. However, the fluororesin powder has a problem that sufficient surface strength cannot be obtained and streak failure due to scratches on the surface of the photoconductor is likely to occur. As described above, the improvement of the surface property of the photoconductor is not sufficient for the realization of high image quality by using the toner having a small particle size, and the improvement from the toner side has been demanded.

On the other hand, research on controlling the shape factor and particle size distribution of the toner is being conducted in response to the demand for higher image quality. Even if the particle size of the toner is reduced, the shape factor and particle size distribution of the toner can be controlled to reduce the adhesion of the toner to the surface of the photoconductor, improve the transferability of the toner, and improve the cleaning property. Attempts have been made to However, when a toner having a small particle size is used, the improvement effect is not as high as initially expected, and improvement in transferability, cleaning property, etc. is still required.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems and to obtain a sufficiently high quality electrophotographic image even by using a toner having a controlled form factor and particle size distribution and a reduced particle size. An image forming method and an image forming apparatus that can be provided.

[0009]

DISCLOSURE OF THE INVENTION As a result of repeated studies to solve the above-mentioned problems, the present inventors have found that the object of the present invention can be achieved by taking any of the following configurations.

That is, 1. A latent image formed on an electrophotographic photoreceptor having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group has a variation coefficient of the shape factor of toner particles of 16% or less. An image forming method comprising developing with a developer using toner.

2. A latent image formed on an electrophotographic photoreceptor having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group has a shape factor of 1.
An image forming method comprising developing with a developer using a toner containing 65% by number or more of toner particles in the range of 2 to 1.6.

3. A toner containing 50% by number or more of toner particles having no corners of a latent image formed on an electrophotographic photoreceptor having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group. An image forming method comprising developing with the developer used.

4. When a latent image formed on an electrophotographic photosensitive member having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group is represented by a toner particle size D (μm) , The natural logarithm lnD is set on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23, and the relative frequency (m ₁ ) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution, An image characterized by being developed with a developer using a toner whose sum (M) with the relative frequency (m ₂ ) of the toner particles included in the second most frequent class is 70% or more. Forming method.

5. A latent image formed on an electrophotographic photosensitive member having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group is used as a toner having a toner particle number variation coefficient of 27% or less. An image forming method comprising developing with the developer used.

6. Item 6. The image forming method described in any one of Items 1 to 5, wherein the compound having a polymerizable functional group is a vinyl monomer represented by the general formula (1).

7. Item 6. The image forming method described in any one of Items 1 to 5, wherein the compound having a polymerizable functional group is a vinyl monomer represented by the general formula (2).

8. 8. The image forming method described in any one of 1 to 7 above, wherein the binder resin is mainly composed of polycarbonate having a siloxane partial structure.

9. 9. The image forming method as described in any one of 1 to 8 above, wherein the polymer formed from the compound having a polymerizable functional group is in a phase separation state with a binder resin.

10. The polymer formed from the compound having a polymerizable functional group is formed by dispersion polymerization in a solution in which a binder resin is dissolved.
9. The image forming method according to any one of 9 above.

11. 11. The image forming method described in any one of 1 to 10 above, wherein the toner is a polymerized toner.

12. The number average particle diameter of the toner is 3.0
The image forming method as described in any one of 1 to 11 above, wherein the image forming method is about 8.5 μm.

13. 13. An image forming apparatus, wherein an electrophotographic image is formed by using the image forming method described in any one of 1 to 12 above.

The present invention will be described in detail below. In the image forming method of the present invention, a latent image formed on an electrophotographic photoreceptor having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group is used to form a latent image formed on the electrophotographic photoreceptor. It is characterized by developing with a developer using a toner having the above. The binder resin is mainly intended to function as a structural component of the surface layer,
The main purpose of the polymer formed from the compound having a polymerizable functional group is to modify the surface layer and to exhibit the function of improving the transferability and cleaning property of the toner. The polymer formed from the compound having a polymerizable functional group (hereinafter, also simply referred to as the polymer of the present invention) is preferably phase-separated from the binder resin. Since the polymer of the present invention is phase-separated without being mixed and melted in the binder resin, the effect of modifying the surface layer can be more remarkably exhibited.

The compound having a polymerizable functional group of the present invention means a monomer compound used in any polymerization system such as radical polymerization, condensation polymerization and addition polymerization. For example, in the case of radical polymerization, a vinyl compound is used. It means a monomer such as a compound, a polyhydric alcohol compound or a dicarboxylic acid compound in the case of condensation polymerization, and an epoxy compound or the like in the case of addition polymerization.

Of these compounds having a polymerizable functional group,
As the compound preferable in the present invention, a vinyl compound used in a radical polymerization system is preferable, and a vinyl monomer represented by the general formula (1) or (2) is particularly preferable.

A polymer formed from a compound having a polymerizable functional group represented by the above general formula (1) or (2) forms a surface layer of a photoconductor together with a binder resin, so that it can be treated under high temperature and high humidity conditions. By improving the water repellency, the surface tension and surface energy of the photoconductor surface layer can be reduced to give the surface water repellency not only under low temperature and low humidity conditions but also under high temperature and high humidity conditions.
Toner transferability without causing image defects,
It is possible to form a surface layer having excellent cleaning properties and abrasion resistance.

Specific examples of the vinyl monomer represented by the general formula (1) include vinyl monomers having the following long-chain alkyl groups having 8 or more carbon atoms.

Compound No. 1-1 Stearyl methacrylate compound No. 1-2 Stearyl acrylate compound No. 1-3 Lauryl methacrylate compound No. 1-4 Lauryl acrylate compound No. 1-5 N-stearyl methacrylamide compound No. 1-6 N-stearyl acrylamide compound No. 1-7 N-laurylmethacrylamide compound No. 1-8 N-lauryl acrylamide compound No. 1-9 Stearyl vinyl ether compound No. 1-10 Lauryl vinyl ether Further, specific examples of the vinyl monomer of the general formula (2) include vinyl monomers containing a long-chain alkyl group having 5 or more carbon atoms as described below.

Compound No. 2-1 1H, 1H, 11H
-Eicosafluorodecyl acrylate compound No. 2-2 1H, 1H, 9H-hexadecafluorononyl acrylate compound No. 2-3 1H, 1H, 7H-dodecafluoroheptyl acrylate compound No. 2-4 1H, 1H, 5H-octafluoropentyl acrylate compound No. 2-5 1H, 1H, 11H-eicosafluorodecyl methacrylate compound No. 2-6 1H, 1H, 9H-hexadecafluorononyl methacrylate compound No. 2-7 1H, 1H, 7H-dodecafluoroheptylmethacrylate compound No. 2-8 1H, 1H, 5H-octafluoropentyl methacrylate compound No. 2-9 3- (perfluoro-5-methylhexyl) ethyl methacrylate compound No. 2-10 2- (perfluoro-7-methyloctyl) ethyl methacrylate compound No. 2-11 N- (1H, 1H, 7H-dodecafluoroheptyl) acrylamide compound No. 2-12 N- (1H, 1H, 5H-octafluoropentyl) acrylamide compound No. 2-13 N- (1H, 1H, 11H-eicosafluorodecyl) methacrylamide compound No. 2-14 N- (1H, 1H, 9H-hexadecafluorononyl) methacrylamide compound No. 2-15 N- (1H, 1H, 7H-dodecafluoroheptyl) methacrylamide compound No. 2-16 N- (1H, 1H, 5H-octafluoropentyl) methacrylamide compound No. 2-17 1H, 1H, 11H-eicosafluorodecyl vinyl ether compound No. 2-18 1H, 1H, 9H-hexadecafluorononyl vinyl ether compound No. 2-19 1H, 1H, 7H-dodecafluoroheptyl vinyl ether compound No. 2-20 1H, 1H, 5H-octafluoropentyl vinyl ether compound No. 2-21 3- (perfluoro-5-methylhexyl) vinyl ether compound No. 2-22 2- (perfluoro-7-methyloctyl) vinyl ether compound No. 2-23 N- (1H, 1H, 11H-eicosafluorodecyl) methacrylamide compound No. 2-24 N- (1H, 1H, 9H-hexadecafluorononyl) acrylamide As the binder resin of the present invention, for example, polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin,
Vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate, silicone resin, melamine resin, and copolymer resin containing two or more of repeating units of these resins. Etc. can be used.

Among these resins, polycarbonates having excellent electrophotographic properties (sensitivity and chargeability) are preferable, and polycarbonates having a siloxane partial structure are more preferable. The polycarbonate having a siloxane partial structure means a polycarbonate having a siloxane group (-SiO-) in a chemical structure having a repeating unit of a carbonate structure (-OCOO-). The polycarbonate having the siloxane partial structure not only functions as a structural component of the surface layer, but also improves the dispersibility of the polymer of the present invention and remarkably improves the transferability from the surface layer of the toner and the cleaning property. You can

Examples of the polycarbonate having the siloxane partial structure include JP-A-5-88398 and JP-A-1.
The polycarbonates described in 1-65136 and the like can be used.

The polycarbonate having a siloxane partial structure preferably has a repeating unit of a carbonate structure having a polydialkylsiloxane partial structure as represented by the following general formulas (3) and (4).

[0033]

[Chemical 3]

(In the general formula (3), R ₈ is an alkylene group or alkylidene group having 2 to 6 carbon atoms, R ₉ and R ₁₀ are alkyl groups having 1 to 3 carbon atoms, a phenyl group or a substituted phenyl group, and n is Indicates an integer of 1 to 200.)

[0035]

[Chemical 4]

(In the general formula (4), R's may be the same or different, and may be an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, B
Is (CH ₂ ) _x , x is an integer of 2 to 6, n is 0 to 200,
Further, as the polycarbonate having a siloxane partial structure, a repeating unit of a carbonate structure having the above polydialkylsiloxane partial structure and a siloxane partial structure represented by the following general formula (5) are used as the polycarbonate having a siloxane partial structure. It is preferably a copolymer of repeating units having a carbonate structure which does not have any.

[0037]

[Chemical 5]

(In the general formula (5), A is a single bond and has 1 carbon atom.
A linear, branched or cyclic alkylidene group of 10
Aryl-substituted alkylidene group, arylene alkylidene group, or -O -, - S -, - CO -, - SO- and -SO ₂ - _{indicates, R 11, R 12, R} 13 and R ₁₄ are a hydrogen atom, a halogen An atom or an alkyl group having 1 to 4 carbon atoms or an alkenyl group is shown. ) Hereinafter, specific examples of the polycarbonate having a siloxane partial structure will be illustrated.

[0039]

[Chemical 6]

[0040]

[Chemical 7]

[0041]

[Chemical 8]

[0042]

[Chemical 9]

The molecular weight of the polycarbonate having a siloxane partial structure is a viscosity average molecular weight of 5,000 to 2
A range of 0,000 is preferred.

The polycarbonate having the siloxane partial structure is used as a main binder resin for forming the surface layer, and the proportion of the surface layer in the total resin is 50% by mass.
The above is preferable.

In addition to the polycarbonate having the siloxane partial structure, for example, polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, A polycarbonate resin, a silicone resin, a melamine resin, a copolymer resin containing two or more of the repeating units of these resins, or the like can also be used in combination.

In forming the surface layer of the present invention, the polymer of the present invention can be synthesized by a dispersion polymerization method. That is, a compound having a polymerizable functional group is dispersed or dissolved together with a polymerization initiator in a solution prepared by dissolving the binder resin in a solvent as a dispersion stabilizer, and a compound having a polymerizable functional group in a mixed solution of these. Polymerization of (1) is advanced to form a polymer in a phase separation state from the binder resin, and the resulting mixed solution can be used as a coating mother liquor for the surface layer.

The concentration of the binder resin used for preparing the coating mother liquor is 0.1 to 2 with respect to 100 parts by mass of the solvent.
00 parts by mass is preferred. If the amount is less than 0.1 parts by mass, the dispersion of the compound having a polymerizable functional group or the polymer formed from the compound is not stable, and if the amount is more than 200 parts by mass, the binder resin is likely to aggregate in the solvent and is uniform. It tends to hinder the formation of polymers.

As the solvent used for preparing the coating mother liquor, a solvent capable of dissolving or dispersing the binder resin and the compound having a polymerizable functional group is used. Organic solvents are generally used as these solvents, but if necessary, a mixed solvent of organic solvents or a mixed solvent of water and an organic solvent can be used.

Examples of the above-mentioned organic solvent include methychlor, ethyl chloride, chloroform, monochlorobenzene, dichlorobenzene, tetrahydrofuran, dioxolane, dioxane, benzene, toluene, xylene, mesitylene, alcohols, esters, hexane, heptane, ligroin, kerosene, Tetralin, ketones, ethers, dimethylformamide, acetonitrile and the like are preferably used.

The following compounds are used as the polymerization initiator used for preparing the coating mother liquor. That is, A
DVN (Azobis- (2,4-dimethylylv
(Aleronitrite)), AIBN- (Azob
isisobutylonitrile), ACPA
(Azobis- (4-cyanopentanoic
acid)), AMBN (Azobis- (2-met
hylbutyronitrile)), BPO (Be
nzoyl peroxide) and the like are preferably used.

A dispersion stabilizing auxiliary agent (an auxiliary agent for stably dispersing a compound having a polymerizable functional group) can be used in the preparation of the coating mother liquor. As the dispersion stabilizing aid, for example, a nonionic surfactant or the like is used.

An example of a method for preparing a coating mother liquor, which will be specifically shown in a synthesis example described later, a binder resin, a compound having a polymerizable functional group, a polymerization initiator and, if necessary, a dispersion stabilizing aid in a solvent (organic solvent). Is uniformly dissolved or dispersed, and if necessary, is polymerized by heating in the presence of other substances (or may be added during the process, if necessary), and the resulting polymer is the binder resin. It is possible to obtain the coating mother liquor generated in the phase separation state. Each of the components (solvent, binder resin, compound having a polymerizable functional group, etc.) used for preparing the coating mother liquor may be a single one, but it is possible to use two or more of them in combination to obtain a polymerizable compound. It is also possible to control the size of the polymer from the compound having a functional group and to generate a copolymer.
It is also possible to use two types of polymerization initiators in combination to adjust the degree of polymerization distribution of the resulting polymer.

The amounts of the components used for preparing the coating mother liquor are preferably used in the following mass ratios.

Preferred mass ratio of material components Binder resin: 0.1 to 200 parts by mass per 100 parts by mass of organic solvent Compound having a polymerizable functional group: 1 to 200 parts by mass per 100 parts by mass of binder resin. Polymerization initiator: 0.01 parts by mass to 50 parts by mass with respect to 100 parts by mass of the compound having a polymerizable functional group Dispersion stabilizing aid: 0.001 parts by mass to 10 parts by mass with respect to 100 parts by mass of the compound having a polymerizable functional group. By using the above mass ratio, it is possible to stably proceed the polymerization. Further, in the above, a method of adding a compound having a polymerizable functional group, a polymerization initiator and the like stepwise or continuously to the polymerization system (process for preparing a coating mother liquor) can also be appropriately used.

In the present invention, the coating mother liquor obtained above may be used as it is as a coating liquid, and the coating liquid may be coated and dried to form the surface layer of the electrophotographic photoreceptor.
A charge-transporting substance, an antioxidant, an additive such as a coating aid are added to the coating mother liquor to prepare a coating liquid for a surface layer,
You may coat and dry and may form the surface layer of an electrophotographic photoreceptor.

Next, the constitution of the electrophotographic photosensitive member of the present invention will be described. The electrophotographic photoreceptor of the present invention is preferably an organic photoreceptor. The surface layer of the present invention is preferably applied to a charge transport layer forming a surface layer of an organic photoreceptor, a protective layer or the like. Hereinafter, the organic photoreceptor using the surface layer of the present invention will be mainly described.

In the present invention, the organic photoreceptor is an electrophotographic photoreceptor constituted by giving an organic compound either one of a charge generating function and a charge transporting function which is essential for the construction of the electrophotographic photoreceptor. This means that it includes all known organic electrophotographic photoreceptors such as a photoreceptor composed of a known organic charge generating material or an organic charge transporting material and a photoreceptor composed of a polymer complex having a charge generating function and a charge transporting function.

The layer structure of the organic photoreceptor is not particularly limited, but a charge generation layer, a charge transport layer, or a charge generation / charge transport layer (a layer having the functions of charge generation and charge transport in the same layer).
It is preferable to adopt a constitution in which a protective layer is coated on the photosensitive layer and the like, if necessary.

Conductive Support As the conductive support used in the photoconductor of the present invention, either a sheet-like or a cylindrical-like one may be used. A support is preferred.

The cylindrical conductive support means a cylindrical support required to form an image endlessly by rotating, and has a straightness of 0.1 mm or less and a shake of 0.1 mm.
A conductive support in the following range is preferable. When the circularity and the shake range are exceeded, good image formation becomes difficult.

As the conductive material, a metal drum of aluminum, nickel or the like, a plastic drum on which aluminum, tin oxide, indium oxide or the like is deposited, or a paper / plastic drum coated with a conductive substance can be used. It is preferable that the conductive support has a specific resistance of 10 ³ Ωcm or less at room temperature.

The conductive support used in the present invention may have a surface on which a sealed alumite film is formed. The alumite treatment is usually carried out in an acidic bath of chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid, etc., but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing treatment in sulfuric acid, it is preferable that the sulfuric acid concentration is 100 to 200 g / L, the aluminum ion concentration is 1 to 10 g / L, the liquid temperature is about 20 ° C., and the applied voltage is about 20 V. It is not limited. The average thickness of the anodized film is usually 2
It is preferably 0 μm or less, and particularly preferably 10 μm or less.

Intermediate Layer In the present invention, an intermediate layer having a barrier function may be provided between the conductive support and the photosensitive layer.

In the present invention, an intermediate layer (lower layer) is provided between the support and the photosensitive layer in order to improve the adhesion between the conductive support and the photosensitive layer or prevent charge injection from the support. (Including a pulling layer) can also be provided. Examples of the material of the intermediate layer include a polyamide resin, a vinyl chloride resin, a vinyl acetate resin, and a copolymer resin containing two or more of repeating units of these resins. Among these undercoat resins, a polyamide resin is preferable as a resin that can reduce the increase in residual potential due to repeated use. The thickness of the intermediate layer using these resins is 0.01 to 0.5 μm.
Is preferred.

The intermediate layer preferably used in the present invention includes an intermediate layer using a curable metal resin obtained by thermosetting an organometallic compound such as a silane coupling agent and a titanium coupling agent. The film thickness of the intermediate layer using the curable metal resin is preferably 0.1 to 2 μm.

The intermediate layer preferably used in the present invention is an intermediate layer in which fine particles of titanium oxide (average particle diameter of 0.01 to 1 μm) subjected to hydrophobic surface treatment are dispersed in a binder such as polyamide resin. To be The thickness of the intermediate layer is preferably 1 to 15 μm.

Photosensitive Layer The photosensitive layer structure of the photoconductor of the present invention may be a photosensitive layer structure of a single layer structure in which one layer has a charge generating function and a charge transporting function on the above-mentioned intermediate layer, but is more preferably a photosensitive layer. It is preferable that the function of the layer is separated into a charge generation layer (CGL) and a charge transport layer (CTL). By adopting a constitution in which the functions are separated, the increase in residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. In the negative charging photoreceptor, the charge generation layer (C
GL) and a charge transport layer (CTL) thereon. In the case of the photoconductor for positive charging, the order of the layers is the reverse of that of the photoconductor for negative charging. The most preferable photosensitive layer structure of the present invention is a negatively charged photosensitive member structure having the above-mentioned function separation structure.

The constitution of the photosensitive layer of the function-separated negatively charged photoreceptor will be described below. Charge Generation Layer The charge generation layer contains a charge generation material (CGM). If necessary, a binder resin and other additives may be contained as other substances.

As the charge generating substance (CGM), a known charge generating substance (CGM) can be used. For example, a phthalocyanine pigment, an azo pigment, a perylene pigment, an azurenium pigment or the like can be used. Among these, CGM that can minimize the increase in residual potential with repeated use
Has a steric structure and a potential structure capable of forming a stable aggregation structure among a plurality of molecules, and specific examples thereof include a phthalocyanine pigment and a perylene pigment CGM having a specific crystal structure. For example, the Bragg angle 2θ with respect to Cu-Kα rays
CGMs such as titanyl phthalocyanine having a maximum peak at 27.2 ° and benzimidazole perylene having a maximum peak at 22.4 at 27.2 have almost no deterioration due to repeated use, and the residual potential increase can be reduced.

When a binder is used as a CGM dispersion medium in the charge generation layer, a known resin can be used as the binder, but the most preferable resin is formal resin, butyral resin, silicone resin, silicone modified butyral resin, phenoxy resin. Resin etc. are mentioned. The ratio of the binder resin to the charge generating substance is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin. By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is preferably 0.01 μm to 2 μm.

Charge Transport Layer When the charge transport layer is the surface layer of the organic photoreceptor, it is preferable to apply the surface layer of the present invention to the charge transport layer.

The charge transport layer contains a charge transport material (CTM) and a binder resin for dispersing CTM to form a film.
As the binder resin, a polymer solution obtained from the binder resin of the present invention and a compound having a polymerizable functional group is used as a coating liquid component, and as other substances, additives such as antioxidants are optionally contained. It is preferable.

As the charge transport material (CTM), a known charge transport material (CTM) can be used. For example, a triphenylamine derivative, a hydrazone compound, a styryl compound, a benzidine compound, a butadiene compound or the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, CTM that can minimize the increase in residual potential due to repeated use has high mobility and has a characteristic that the difference in ionization potential with CGM to be combined is 0.5 (eV) or less, and preferably 0. It is 0.25 (eV) or less.

The ionization potentials of CGM and CTM are measured by a surface analyzer AC-1 (manufactured by Riken Keiki Co., Ltd.).

When the charge transport layer is not the surface layer, examples of the resin used for the charge transport layer (CTL) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, and epoxy resin. , Polyurethane resins, phenol resins, polyester resins, alkyd resins, polycarbonate resins, silicone resins, melamine resins, and copolymer resins containing two or more of the repeating units of these resins. Further, a high molecular weight organic semiconductor such as poly-N-vinylcarbazole may be used. Polycarbonate is particularly preferable for maintaining good electrophotographic characteristics (chargeability, sensitivity, etc.).

Surface Layer (Protective Layer) The above coating mother liquor may be used as it is as the coating liquid for the surface layer, and the coating liquid may be coated and dried to form the surface layer of the electrophotographic photoreceptor, or the above coating. Charge transport material in mother liquor,
The surface layer of the electrophotographic photoreceptor may be formed by adding an additive such as an antioxidant or a coating aid to prepare a surface layer coating solution, coating and drying the solution. In order to maintain good electrophotographic properties (chargeability, sensitivity, etc.), the surface layer also has a charge transport layer,
The presence of an antioxidant or the like is more preferable.

Further, it is preferable that the surface layer contains an antioxidant. The antioxidant is a typical one that does not prevent the action of oxygen on the auto-oxidizing substance existing in the organic photoreceptor or on the surface of the organic photoreceptor under the conditions of light, heat, discharge, etc. It is a substance that has an inhibitory property. Typically, the following compounds are listed.

[0078]

[Chemical 10]

[0079]

[Chemical 11]

[0080]

[Chemical 12]

[0081]

[Chemical 13]

The solvent or dispersion medium used for forming the intermediate layer, the photosensitive layer, the protective layer and the like includes n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine,
N, N-dimethylformamide, acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane, 1,
1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolane,
Dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cellosolve and the like can be mentioned. The present invention is not limited to these, but dichloromethane, 1,2-dichloroethane, methyl ethyl ketone and the like are preferably used. Further, these solvents can be used alone or as a mixed solvent of two or more kinds.

Next, as a coating processing method for producing the electrophotographic photosensitive member of the present invention, dip coating, spray coating,
A coating method such as circular amount control type coating is used, but the coating process on the upper layer side of the photosensitive layer does not dissolve the lower layer film as much as possible, and in order to achieve uniform coating process, spray coating or circular amount control type ( A circular slide hopper type is a typical example. It is preferable to use a coating processing method such as coating. It is most preferable to use the circular amount-regulating type coating processing method for the resin layer of the present invention. The circular amount control type coating is described in detail, for example, in JP-A-58-189061.

Next, the toner of the present invention will be described.
The toner of the present invention has a variation coefficient of the shape coefficient of toner particles of 16% or less, a proportion of toner particles having a shape coefficient of toner particles of 1.2 to 1.6 of 65% by number or more, and a toner having no corner The ratio of particles is 50% by number or more, and the number variation coefficient in the number particle size distribution of toner particles is 2
7% or less, when the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is a histogram showing a number-based particle size distribution divided into a plurality of classes at 0.23 intervals. The sum (M) of the relative frequency (m ₁ ) of the toner particles included in the most frequent class and the relative frequency (m ₂ ) of the toner particles included in the next most frequent class is 70.
% Or more.

That is, as the toner contained in the developer used in the present invention, a toner satisfying at least one of the above conditions (1) to (4) is used to transfer the toner from the photoreceptor having the surface layer. And cleaning properties can be improved. In particular, it is most preferable to use a toner satisfying all the above conditions.

Hereinafter, the above toners will be described. Toner Shape Factor (= Shape Factor of Toner Particles) The shape factor of toner particles is represented by the following formula and indicates the degree of roundness of toner particles.

Shape factor = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter means the parallel line when a projected image of toner particles on a plane is sandwiched by two parallel lines. Refers to the width of the particles at which the interval is maximum. The projected area means the area of the projected image of the toner particles on the plane.

In the present invention, this shape factor is determined by taking a photograph of a toner particle magnified 2000 times with a scanning electron microscope, and then using this photograph, "SCANNING" is taken.
It was measured by analyzing a photographic image using "IMAGE ANALYZER" (manufactured by JEOL Ltd.). At this time, the shape factor of the present invention was measured by the above calculation formula using 100 toner particles.

The toner of the present invention has a shape factor of 1.2.
The ratio of the toner particles in the range of to 1.6 is 65% by number or more, and preferably 70% by number or more.

In the present invention, a latent image formed on an electrophotographic photoreceptor having a surface layer containing a polymer formed from the binder resin and a compound having a polymerizable functional group has a shape factor of 1.2 to By developing with a developer containing 65% by number or more of toner particles in the range of 1.6, the transferability and cleaning properties of the toner are improved, and an electrophotographic image with good sharpness can be obtained.

The method of controlling the shape factor is not particularly limited. For example, by a method of spraying toner particles in a hot air flow, a method of repeatedly applying mechanical energy by impact force in a gas phase in a gas phase, a method of adding a toner to a solvent that does not dissolve and giving a swirling flow, etc. There is a method in which toner particles having a shape factor of 1.2 to 1.6 are prepared and added into a normal toner so as to be within the range of the present invention and adjusted. Further, there is a method in which the overall shape is controlled at the stage of preparing a so-called polymerization toner, and toner particles whose shape coefficient is adjusted to 1.2 to 1.6 are similarly added to a normal toner for adjustment.

Among the above methods, a polymerization toner (also referred to as a polymerization toner) is preferable as it is a simple manufacturing method and has an excellent surface uniformity as compared with a pulverized toner.

The polymerized toner means a toner obtained by forming a resin for a binder for a toner, forming a toner shape by polymerizing a raw material monomer of a binder resin, and then performing a chemical treatment. More specifically, it means a toner obtained through a polymerization reaction such as suspension polymerization and emulsion polymerization and, if necessary, a fusion step of particles performed thereafter. In the polymerized toner, the raw material monomer is uniformly dispersed in an aqueous system and then polymerized to produce a toner, so that a toner having a uniform particle size distribution and shape can be obtained.

Coefficient of Variation of Shape Factor of Toner (= Variation Coefficient of Shape Factor of Toner Particles) The “coefficient of variation of shape coefficient” of the toner particles of the present invention is calculated from the following formula.

Coefficient of variation = [S / K] × 100 (%) [In the formula, S ₁ represents the standard deviation of the shape factors of 100 toner particles, and K represents the average value of the shape factors. In the toner of the present invention, the variation coefficient of the shape factor is 16% or less, preferably 14% or less.

In the present invention, a latent image formed on an electrophotographic photosensitive member having a surface layer containing a polymer formed from the binder resin and a compound having a polymerizable functional group has a variation coefficient of the shape factor of 16 By developing with a developer using a toner whose content is at most%, the transferability and cleaning properties of the toner are improved, and an electrophotographic image with good sharpness can be obtained.

In order to uniformly control the shape factor and the variation coefficient of the shape factor of the toner without extremely lot-to-lot variation, resin particles (polymer particles) constituting the toner of the present invention are prepared (polymerized), and the resin In the process of fusing and controlling the shape of the particles, an appropriate process end time may be determined while monitoring the characteristics of the toner particles (colored particles) being formed.

Monitoring means that a measuring device is installed in-line and the process conditions are controlled based on the measurement result. That is, in the case of a polymerization toner in which measurement of a shape or the like is incorporated inline, for example, a resin toner is formed by associating or fusing resin particles in an aqueous medium, the shape and the particle size are measured while performing sequential sampling in the steps such as fusing. Is measured, and the reaction is stopped when the desired shape is obtained.

The monitoring method is not particularly limited, but a flow type particle image analyzer FPIA-
2000 (manufactured by Toa Medical Electronics Co., Ltd.) can be used. This device is suitable because the shape can be monitored by performing image processing in real time while passing the sample liquid. That is, a pump or the like is used from the reaction field to constantly monitor and measure the shape and the like, and the reaction is stopped when the desired shape or the like is obtained.

Coefficient of Number Variation of Toner (= Coefficient of Variation of Number of Toner Particles) The number particle size distribution and number variation coefficient of the toner particles of the present invention are measured by Coulter Counter TA- or Coulter Multisizer (manufactured by Coulter Co.). is there. In the present invention, a Coulter Multisizer was used, and an interface (manufactured by Nikkaki Co., Ltd.) for outputting the particle size distribution and a personal computer were connected and used.
The aperture used in the Coulter Multisizer was 100 μm, and the volume and number of toner particles of 2 μm or more were measured to calculate the particle size distribution and average particle size. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size represents the median diameter in the number particle size distribution. The “number variation coefficient in the number particle size distribution” of toner particles is calculated from the following formula.

Number variation coefficient = [S / Dn] × 100 (%) [In the formula, S ₂ represents the standard deviation in the number particle size distribution,
D _n represents the number average particle diameter (μm). The number variation coefficient of the toner particles of the present invention is 27% or less, preferably 25% or less.

In the present invention, the latent image formed on an electrophotographic photoreceptor having a surface layer containing a polymer formed from the binder resin and a compound having a polymerizable functional group has a toner particle number variation coefficient of 27. By developing with a developer using a toner whose content is less than 100%, the transferability of the toner,
The cleaning property is improved, and an electrophotographic image with good sharpness can be obtained.

The method of controlling the number variation coefficient in the toner of the present invention is not particularly limited. For example, a method of classifying toner particles by wind force can be used, but classification in a liquid is effective for reducing the number variation coefficient. As a method of classifying in this liquid, there is a method of controlling the number of revolutions and separately collecting and preparing toner particles according to the difference in sedimentation speed caused by the difference in toner particle diameter.

Particularly when a toner is produced by the suspension polymerization method, a classification operation is indispensable in order to keep the number variation coefficient in the number particle size distribution at 27% or less. In the suspension polymerization method,
Before the polymerization, it is necessary to disperse the polymerizable monomer into an oil droplet having a desired size as a toner in an aqueous medium. That is, the large oil droplets of the polymerizable monomer are repeatedly mechanically sheared by a homomixer or a homogenizer to reduce the oil droplets to the size of toner particles. In the method of different shearing, the number particle size distribution of the obtained oil droplets becomes wide, and therefore,
The toner obtained by polymerizing this also has a wide particle size distribution. For this reason, classification operation is essential.

Ratio of toner particles having no corners Among the toner particles constituting the toner of the present invention, the ratio of toner particles having no corners is required to be 50% by number or more, and this ratio is 70% by number or more. It is preferable.

Of the toner particles constituting the toner of the present invention,
The proportion of toner particles having no corners is preferably 50% by number or more, and more preferably 70% by number or more.

In the present invention, the ratio of toner particles having no corners to the latent image formed on the electrophotographic photoreceptor having the surface layer containing the polymer formed from the binder resin and the compound having a polymerizable functional group is By developing with a developer using a toner of 50% by number or more, the transferability and cleaning property of the toner are improved, and an electrophotographic image with good sharpness can be obtained.

The term "cornerless toner particles" as used herein means toner particles having substantially no protrusions on which electric charges are concentrated or protrusions that are easily worn by stress.
Specifically, the following toner particles are referred to as cornerless toner particles. That is, as shown in FIG. 2A, the toner particles T
When the major axis of L is L, a circle C of radius (L / 10)
When the inside of the toner particle T is rolled while making contact with the inside of the toner particle T at one point, the case where the circle C does not substantially extend outside the toner T is referred to as “toner particle without corners”. The term “when substantially not protruding” means a case where there is one or less protrusions with protruding circles. Also,
The “major axis of toner particles” refers to the width of the particles that maximizes the distance between the parallel lines when the projected image of the toner particles on a plane is sandwiched by two parallel lines. 2B and 2C show projected images of the toner particles having corners, respectively.

The proportion of toner particles having no corners was measured as follows. First, a photograph of a magnified toner particle is taken with a scanning electron microscope and further magnified to 15,0.
A photographic image of 00 times is obtained. Then, the presence or absence of the above-mentioned corner is measured for this photographic image. This measurement was performed on 100 toner particles.

The method for obtaining the toner without corners is not particularly limited. For example, as described above as a method of controlling the shape factor, a method of spraying toner particles in a hot air flow, a method of repeatedly applying mechanical energy due to impact force in a gas phase, or a method of dissolving toner It can be obtained by adding it to a solvent that does not contain it and imparting a swirling flow.

Further, in the polymerization toner formed by associating or fusing resin particles, the surface of the fused particles has many irregularities at the step of stopping the fusion, and the surface is not smooth, but in the shape control step. The toner having no corners can be obtained by appropriately adjusting the conditions such as the temperature, the rotation speed of the stirring blade, and the stirring time. These conditions vary depending on the physical properties of the resin particles, but for example, by setting the glass transition temperature of the resin particles or higher to a higher rotation speed, the surface becomes smooth and toner without corners can be formed.

Particle Size of Toner Particles The particle size of the toner of the present invention is preferably 3-8 μm in number average particle size. In the case where toner particles are formed by a polymerization method, this particle diameter is used in the toner production method described in detail later, in the concentration of the aggregating agent, the amount of the organic solvent added, the fusing time, and the composition of the polymer itself. Can be controlled by.

When the number average particle diameter is 3.0 to 8.5 μm, the transfer efficiency is increased, the halftone image quality is improved, and the image quality of fine lines and dots is improved.

The toner of the present invention has a toner particle diameter D
(Μm), the natural logarithm lnD is taken as the horizontal axis, and the horizontal axis shows the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The toner (M) is 70% or more in sum of the frequency (m ₁ ) and the relative frequency (m ₂ ) of the toner particles included in the second most frequent class.

In the present invention, the latent image formed on the electrophotographic photoreceptor having the surface layer containing the polymer formed from the binder resin and the compound having a polymerizable functional group is compared with the relative frequency (m ₁ ). By developing with a developer using a toner whose sum (M) with the frequency (m ₂ ) is 70% or more, the transferability and cleaning property of the toner are improved and an electrophotographic image with good sharpness is obtained. To be

In the present invention, the histogram showing the number-based particle size distribution has a natural logarithm lnD (D: particle size of individual toner particles) in a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84-2.07: 2.07-2.30: 2.30-
2.53: 2.53 to 2.76 ...), which is a histogram showing a number-based particle size distribution, and the histogram shows particle size data of a sample measured by a Coulter Multisizer according to the following conditions. Is transferred to a computer via an I / O unit and is created by the particle size distribution analysis program in the computer. [Measurement conditions] (1) Aperture: 100 μm (2) Sample preparation method: Electrolyte solution [ISOTON R-1
1 (manufactured by Coulter Scientific Japan)
An appropriate amount of a surfactant (neutral detergent) is added to 50 to 100 ml and stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by subjecting it to an ultrasonic disperser for 1 minute.

Method for Producing Toner The toner of the present invention is preferably a toner obtained by polymerizing at least a polymerizable monomer in an aqueous medium, and is obtained by associating at least resin particles in an aqueous medium. It is preferable that the toner is a toner. Hereinafter, the method for producing the toner of the present invention will be described in detail.

The toner of the present invention is obtained by emulsion polymerization of a monomer in a suspension polymerization method or in a liquid (in an aqueous medium) containing an emulsion of necessary additives to obtain fine polymer particles (resin particles). ) Is prepared, and then an organic solvent, an aggregating agent and the like are added to associate the resin particles. Here, "association" means fusion of a plurality of the resin particles, and includes the case where the resin particles and other particles (for example, colorant particles) are fused.

As an example of the method for producing the toner of the present invention, a coloring agent in a polymerizable monomer and, if necessary, a release agent,
Various constituent materials such as a charge control agent and a polymerization initiator are added, and various constituent materials are dissolved or dispersed in the polymerizable monomer with a homogenizer, a sand mill, a sand grinder, an ultrasonic disperser or the like. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an oil droplet having a desired size as a toner in a water-based medium containing a dispersion stabilizer by using a homomixer or a homogenizer. After that, the stirring mechanism is moved to a reaction device (stirring device) which is a stirring blade described later, and the polymerization reaction is advanced by heating. After completion of the reaction, the dispersion stabilizer is removed, filtered, washed, and dried to prepare the toner of the present invention.

The "aqueous medium" as referred to in the present invention
Means at least 50% by mass of water.

Further, as a method for producing the toner of the present invention, a method of preparing resin particles by associating or fusing them in an aqueous medium can be mentioned. This method is not particularly limited, but for example, JP-A-5-26
The methods shown in JP-A-5252, JP-A-6-329947 and JP-A-9-15904 can be mentioned. That is, a method of associating a plurality of resin particles and dispersed particles of a constituent material such as a colorant, or a plurality of fine particles composed of a resin and a colorant, in particular, after dispersing these in water with an emulsifier, the critical aggregation concentration At the same time as salting out by adding the aggregating agent above, while gradually growing the particle size while forming fused particles by heat fusion above the glass transition temperature of the polymer itself formed, the target particle size and When this happens, a large amount of water is added to stop the particle size growth, the surface of the particles is smoothed while heating and stirring to control the shape, and the particles are heated and dried in a fluid state in a water-containing state. The inventive toner can be formed. Here, a solvent that can be infinitely dissolved in water may be added simultaneously with the coagulant.

The polymerizable monomer used for the resin is styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, 3,4- Dichlorostyrene,
p-phenylstyrene, p-ethylstyrene, 2,4-
Dimethyl styrene, p-tert-butyl styrene, p
-N-hexyl styrene, pn-octyl styrene,
pn-nonylstyrene, pn-decylstyrene, p
Styrene or styrene derivative such as -n-dodecyl styrene, methyl methacrylate, ethyl methacrylate,
N-butyl methacrylate, isopropyl methacrylate,
Methacrylate ester derivatives such as isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate. , Methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate,
Acrylic ester derivatives such as n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate and phenyl acrylate, olefins such as ethylene, propylene and isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide , Vinyl fluoride, vinylidene fluoride, and other halogen-based vinyls, vinyl propionate, vinyl acetate, vinyl benzoate, and other vinyl esters, vinyl methyl ether, vinyl ethyl ether, and other vinyl ethers, vinyl methyl ketone, vinyl ethyl ketone , Vinyl ketones such as vinyl hexyl ketone, N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone, vinyl compounds such as vinyl naphthalene and vinyl pyridine, acrylonitrile, Acrylonitrile, there are acrylic acid or methacrylic acid derivatives such as acrylamide. These vinyl monomers can be used alone or in combination.

Further, it is more preferable to use a combination of those having an ionic dissociative group as the polymerizable monomer constituting the resin. For example, those having a substituent such as a carboxyl group, a sulfonic acid group, and a phosphoric acid group as a constituent group of the monomer, and specifically, acrylic acid, methacrylic acid,
Maleic acid, itaconic acid, cinnamic acid, fumaric acid, maleic acid monoalkyl ester, itaconic acid monoalkyl ester, styrenesulfonic acid, allylsulfosuccinic acid, 2-acrylamido-2-methylpropanesulfonic acid, acid phosphooxyethyl Methacrylate,
3-chloro-2-acid phosphooxypropyl methacrylate and the like can be mentioned.

Further, divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate,
It is also possible to use a polyfunctional vinyl such as neopentyl glycol diacrylate to form a resin having a crosslinked structure.

These polymerizable monomers can be polymerized by using a radical polymerization initiator. In this case, an oil-soluble polymerization initiator can be used in the suspension polymerization method. As this oil-soluble polymerization initiator, 2,2'-azobis- (2,4
-Dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvalero Azo-based or diazo-based polymerization initiators such as nitrile and azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide. , Dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis-
Examples include peroxide polymerization initiators such as (4,4-t-butylperoxycyclohexyl) propane and tris- (t-butylperoxy) triazine, and polymer initiators having a peroxide in the side chain. .

When the emulsion polymerization method is used, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetic acid salts, azobiscyanovaleric acid and its salts, and hydrogen peroxide.

Examples of the dispersion stabilizer include tricalcium phosphate, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate. , Barium sulfate,
Examples thereof include bentonite, silica and alumina. Furthermore, polyvinyl alcohol, gelatin, methyl cellulose, sodium dodecylbenzene sulfonate, ethylene oxide adduct, higher alcohol sodium sulfate, and the like which are commonly used as surfactants can be used as the dispersion stabilizer.

As the excellent resin in the present invention, those having a glass transition point of 20 to 90 ° C. are preferable and a softening point of 8 is obtained.
It is preferably 0 to 220 ° C. The glass transition point is measured by a differential calorimetric method, and the softening point can be measured by a Koka type flow tester. Furthermore, these resins have a number average molecular weight (Mn) of 10 as measured by gel permeation chromatography.
00-100,000, 200 in weight average molecular weight (Mw)
It is preferably 0 to 1,000,000. Furthermore, as the molecular weight distribution, Mw / Mn is 1.5 to 100, and particularly 1.8.
The thing of -70 is preferable.

The aggregating agent used for associating the resin particles in the aqueous medium is not particularly limited, but those selected from metal salts are preferably used.
Specifically, monovalent metals such as salts of alkali metals such as sodium, potassium and lithium, divalent metals such as alkaline earth metal salts such as calcium and magnesium, divalent metals such as manganese and copper. And salts of trivalent metals such as iron and aluminum, and specific salts include sodium chloride, potassium chloride, lithium chloride, calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate and the like. Can be mentioned. These may be used in combination.

It is preferable to add these coagulants at a critical coagulation concentration or higher. This critical coagulation concentration is an index relating to the stability of the aqueous dispersion, and indicates the concentration at which coagulation occurs when a coagulant is added. This critical aggregation concentration is
It greatly changes depending on the emulsified component and the dispersant itself. For example, Seizo Okamura et al., "Polymer Chemistry 1"
7, 601 (1960) edited by The Polymer Society of Japan ”and the like, and a detailed critical aggregation concentration can be obtained.
As another method, a desired salt is added to the target particle dispersion at different concentrations, the ζ (zeta) potential of the dispersion is measured, and the salt concentration at which this value changes is determined as the critical aggregation concentration. You can also ask.

The addition amount of the coagulant of the present invention may be a critical coagulation concentration or more, but is preferably 1.2 of the critical coagulation concentration.
It is better to add it at least twice, more preferably at least 1.5 times.

As the "solvent which is infinitely soluble in water" used together with the aggregating agent, one which does not dissolve the resin to be formed is selected. Specific examples thereof include alcohols such as methanol, ethanol, propanol, isopropanol, t-butanol, methoxyethanol, butoxyethanol, nitriles such as acetonitrile, and ethers such as dioxane. Particularly, ethanol, propanol and isopropanol are preferable.

The amount of the solvent infinitely soluble in water is 1 to 1 with respect to the polymer-containing dispersion liquid to which the coagulant is added.
00% by volume is preferred.

Incidentally, in order to make the particle shape uniform,
It is preferable to prepare colored particles, and after filtering, fluidize and dry the slurry in which 10% by mass or more of water is present with respect to the particles. At this time, it is particularly preferable that the polymer has a polar group. The reason for this is considered to be that the presence of water has an effect of swelling the polymer having a polar group to some extent, so that the homogenization of the shape is particularly likely to be achieved.

The toner of the present invention contains at least a resin and a colorant, but if necessary, it may contain a releasing agent which is a fixing property improving agent, a charge control agent and the like. Further, an external additive composed of inorganic fine particles, organic fine particles or the like may be added to the toner particles containing the resin and the colorant as main components.

As the colorant used in the toner of the present invention, carbon black, a magnetic substance, a dye, a pigment or the like can be optionally used. Examples of the carbon black include channel black, furnace black, acetylene black,
Thermal black, lamp black, etc. are used. Ferromagnetic metals such as iron, nickel, and cobalt as magnetic materials,
Alloys containing these metals, compounds of ferromagnetic metals such as ferrite and magnetite, alloys containing no ferromagnetic metals but exhibiting ferromagnetism by heat treatment, such as manganese-copper-
Aluminum, manganese-copper-tin, and other types of alloys called Heusler alloys, chromium dioxide, and the like can be used.

As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 1
22, C.I. I. Solvent Yellow 19, 44, 7
7, ibid 79, ibid 81, ibid 82, ibid 93, ibid 98, ibid 10
3, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 9
5 and the like can be used, and a mixture thereof can also be used. As the pigment, C.I. I. Pigment Red 5,
48: 1, 53: 1, 57: 1, 122, 1
39, 144, 149, 166, 177, 1
78, ibid. 222, C.I. I. Pigment Orange 31, the same 43, C.I. I. Pigment Yellow 14, Same 17 and Same 9
3, 94, 138, C.I. I. Pigment Green 7, C.I. I. Pigment Blue 15: 3, 60 and the like, and a mixture thereof can also be used. The number average primary particle size varies depending on the type, but is generally about 10
About 200 nm is preferable.

As the method for adding the colorant, the polymer particles prepared by the emulsion polymerization method are added at the stage of aggregating by adding an aggregating agent to color the polymer, or the step of polymerizing a monomer. It is possible to use a method in which a coloring agent is added and polymerized to obtain colored particles. When the colorant is added at the stage of preparing the polymer, it is preferable that the surface is treated with a coupling agent or the like so as not to hinder radical polymerizability.

Further, low molecular weight polypropylene (number average molecular weight = 1500 to 9000) or low molecular weight polyethylene as a fixability improving agent may be added.

Similarly, various charge control agents are known,
Moreover, the thing which can be disperse | distributed in water can be used. Specifically, nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines,
Examples thereof include secondary ammonium salt compounds, azo-based metal complexes, salicylic acid metal salts or metal complexes thereof.

The particles of these charge control agents and fixability improvers have a number average primary particle diameter of 10 to 50 in a dispersed state.
It is preferably about 0 nm.

In the toner of the present invention, the effect can be more enhanced by adding fine particles such as inorganic fine particles and organic fine particles as an external additive. The reason for this is presumed to be that the embedding and detachment of the external additive can be effectively suppressed, and the effect is remarkable.

As the inorganic fine particles, it is preferable to use inorganic oxide particles such as silica, titania, and alumina. Further, these inorganic fine particles are subjected to a hydrophobic treatment with a silane coupling agent or a titanium coupling agent. preferable. The degree of hydrophobic treatment is not particularly limited, but methanol wettability of 40 to 95 is preferable. Methanol wettability is an evaluation of wettability with respect to methanol. In this method, 50 ml of distilled water placed in a beaker with an internal volume of 200 ml was charged with inorganic fine particles to be measured in an amount of 0.
Weigh 2 g and add. Methanol is dripped slowly from a buret whose tip is dipped in the liquid, with slow stirring until all the inorganic fine particles become wet. When the amount of methanol required to completely wet the inorganic fine particles is a (ml), the degree of hydrophobicity is calculated by the following formula.

Hydrophobicity = (a / (a + 50)) × 100 The addition amount of this external additive is 0.1 to 5% in the toner.
It is 0% by mass, preferably 0.5 to 4.0% by mass. Further, various external additives may be used in combination.

A suspension polymerization method toner in which a toner constituent component such as a colorant or the like is dispersed or dissolved in a so-called polymerizable monomer is suspended in an aqueous medium and then polymerized to obtain a toner is subjected to a polymerization reaction. The shape of the toner particles can be controlled by controlling the flow of the medium in the reaction vessel. That is, when a large number of toner particles having a shape factor of 1.2 or more are formed, the flow of the medium in the reaction vessel is made turbulent, and the polymerization proceeds to exist in the aqueous medium in a suspended state. When the oil droplets gradually become polymerized and become soft particles, the particles collide with each other to promote coalescence of the particles, and particles with an irregular shape are obtained. . Further, in the case of forming substantially spherical toner particles having a shape factor of less than 1.2, the flow of the medium in the reaction vessel is made a laminar flow, and collision of the particles is avoided to obtain substantially spherical particles. By this method,
The toner shape distribution can be controlled within the scope of the present invention.

Next, the reaction apparatus preferably used for producing the polymerized toner will be described. 3 and 4 are a perspective view and a cross-sectional view showing an example of a polymerized toner reaction device, respectively. In the reactor shown in FIGS. 3 and 4, a rotating shaft 3j is vertically installed at the center of a vertical cylindrical stirring tank 2j having a jacket 1j for heat exchange mounted on the outer periphery thereof.
The rotating shaft 3j is provided with a lower stirring blade 40j arranged near the bottom surface of the stirring tank 2j and a stirring blade 50j arranged further above. The upper-stage stirring blade 50j is arranged at an intersection angle α preceding the lower-stage stirring blade 40j in the rotational direction. In the case of producing the toner of the present invention, the crossing angle α is preferably less than 90 degrees (°). The lower limit of the intersection angle α is not particularly limited, but is preferably about 5 ° or more, and more preferably 10 ° or more. When three-stage stirring blades are provided, the intersecting angle α between adjacent stirring blades is preferably less than 90 degrees.

With such a structure, the medium is first stirred by the stirring blade 50j arranged in the upper stage, and a downward flow is formed. Then, the stirring blade 40j arranged in the lower stage accelerates the flow formed by the stirring blade 50j in the upper stage further downward, and the stirring blade 50j
It is presumed that a downward flow is also formed by itself, and the flow accelerates and progresses as a whole. As a result, a basin having a large shear stress formed as a turbulent flow is formed, and it is presumed that the shape of the obtained toner particles can be controlled.

3 and 4, the arrow indicates the direction of rotation, 7j is an upper material charging port, 8j is a lower material charging port, and 9j is a turbulent flow forming member for making stirring effective.

The shape of the stirring blade is not particularly limited, but it has a rectangular plate shape, a blade with a notch, and a central portion with one or more holes, so-called slits. Things etc. can be used. Specific examples of these are shown in FIG. Stirring blade 5 shown in FIG.
a has no central hole, the stirring blade 5b shown in FIG. 6B has a large central hole 6b in the center, and the stirring blade 5c shown in FIG. 6C has a horizontally long central hole 6c (slit). ), The stirring blade 5d shown in FIG.
There is a (slit). Further, in the case of providing a three-stage stirring blade, even if the middle hole portion formed in the upper stirring blade and the middle hole portion formed in the lower stirring blade are different, they may be the same. It may be.

The gap between the upper-stage and lower-stage stirring blades having the above-mentioned structure is not particularly limited, but it is preferable that there is at least a gap between the stirring blades. The reason for this is not clear, but it is considered that the stirring efficiency is improved because the flow of the medium is formed through the gap. However, the gap has a width of 0.5 to 50%, preferably a width of 1 to 30% with respect to the liquid surface height in a stationary state.

The size of the stirring blade is not particularly limited, but the total height of all stirring blades is 50% to 100%, preferably 60% to 50% of the liquid surface height in a stationary state. 95
%.

On the other hand, in the case of a polymerization method toner in which resin particles are associated or fused in an aqueous medium, the flow and temperature distribution of the medium in the reaction vessel at the fusion stage are controlled to further improve the shape after fusion. By controlling the heating temperature, stirring rotation number, and time in the control step, the shape distribution and shape of the entire toner can be arbitrarily changed.

That is, in the case of a polymerization toner in which resin particles are associated or fused, the flow in the reaction device is laminar,
By using a stirring blade and a stirring tank that can make the internal temperature distribution uniform, by controlling the temperature, rotation speed, and time in the fusion process and shape control process, the desired shape factor and uniform A toner having a shape distribution can be formed. The reason for this is that when fusion is performed in a laminar flow-forming place, strong stress is not applied to particles (association or agglomerated particles) in which aggregation and fusion are progressing, and in a laminar flow in which the flow is accelerated, It is presumed that, as a result of the uniform temperature distribution in the stirring tank, the shape distribution of the fused particles becomes uniform. Furthermore, heating in the subsequent shape control process,
By stirring, the fused particles gradually become spherical and the shape of the toner particles can be arbitrarily controlled.

As the stirring tank used in the production of the polymerization method toner in which the resin particles are associated or fused, the same one as in the suspension polymerization method can be used. In this case, it is necessary not to provide an obstacle such as a baffle plate that forms a turbulent flow in the stirring tank.

The shape of the stirring blade is not particularly limited as long as it forms a laminar flow and does not form a turbulent flow. However, a continuous surface such as a rectangular plate shown in FIG. What is formed is preferable, and may have a curved surface.

The toner of the present invention is used, for example, as a one-component magnetic toner containing a magnetic material, as a two-component developer mixed with a so-called carrier, or as a non-magnetic toner alone. However, in the present invention, it is preferably used as a two-component developer mixed with a carrier.

Next, the image forming apparatus of the present invention will be described. FIG. 1 is a sectional configuration diagram of an example of the image forming apparatus of the present invention.

In FIG. 1, 50 is a photosensitive drum (photosensitive member) which is an image bearing member, and an organic photosensitive layer is applied onto the drum.
A photosensitive member having the resin layer of the present invention applied thereon is grounded and driven and rotated clockwise. Reference numeral 52 denotes a scorotron charger (charging means) for uniformly charging the peripheral surface of the photosensitive drum 50 by corona discharge. This charger 5
Prior to the charging by 2, the exposure may be performed by the pre-charge pre-exposure unit 51 using a light emitting diode or the like to eliminate the history of the photo conductor in the pre-image formation to eliminate the charge on the peripheral surface of the photo conductor.

After the photosensitive member is uniformly charged, the image exposing device 53 as the image exposing means performs image exposure based on the image signal. The image exposure device 53 in this figure uses a laser diode (not shown) as an exposure light source. Rotating polygon mirror 5
Scanning on the photosensitive drum is performed by the light whose optical path is bent by the reflection mirror 532 through the 31, f.theta.
An electrostatic latent image is formed.

Here, the reversal development process of the present invention means that the surface of the photoconductor is uniformly charged by the charger 52 to develop the image-exposed region, that is, the exposed portion potential (exposed portion region) of the photosensitive member. It is an image forming method that visualizes by a step (means). On the other hand, the unexposed portion potential is not developed by the developing bias potential applied to the developing sleeve 541.

The electrostatic latent image is then developed by the developing device 54 as a developing means. A developing device 54 containing a developer composed of toner and carrier is provided on the periphery of the photosensitive drum 50, and development is performed by a developing sleeve 541 that contains a magnet and holds the developer and rotates.
Inside the developing unit 54, the developer stirring and conveying members 544, 543,
The developer is constituted by a conveyance amount regulating member 542 and the like, and the developer is agitated and conveyed to be supplied to the developing sleeve, and the supply amount is controlled by the conveyance amount regulating member. The amount of the developer conveyed varies depending on the linear velocity of the applied organic electrophotographic photosensitive member and the specific gravity of the developer, but is generally 20 to 200 m.
It is in the range of g / cm ² .

The developer is, for example, a carrier in which an insulating resin is coated around the above-mentioned ferrite core, a coloring agent such as carbon black and a charge control agent mainly composed of the above-mentioned styrene acrylic resin, and a charge control agent of the present invention. Colored particles consisting of low molecular weight polyolefin, and toner externally added with silica, titanium oxide, etc., the developer is transported to the developing zone with the layer thickness regulated by the transport amount regulating member, and development is carried out. . At this time, normally, a DC bias is applied between the photosensitive drum 50 and the developing sleeve 541, and if necessary, an AC bias voltage is applied to develop. Further, the developer is developed in a state of being in contact with or non-contacting with the photoreceptor. The potential sensor 547 measures the potential of the photoconductor.
Is provided above the developing position as shown in FIG.

After the image formation, the recording paper P is fed to the transfer area by the rotation operation of the paper feed roller 57 when the transfer timing is adjusted.

In the transfer area, the transfer electrodes (transfer means: transfer device) 58 on the peripheral surface of the photosensitive drum 50 are activated in synchronization with the transfer timing, and the recording paper P fed is sandwiched and transferred. It

Then, the recording paper P is destaticized by a separating electrode (separator) 59 which is activated almost at the same time as the transfer electrode, is separated by the peripheral surface of the photosensitive drum 50 and is conveyed to the fixing device 60, and is heated by a heat roller. 601 and pressure roller 6
The toner is melted by heating and pressurizing 02, and then discharged to the outside of the apparatus through the paper discharge roller 61. The transfer electrode 58 and the separation electrode 59 are withdrawn from the peripheral surface of the photoconductor drum 50 after the recording paper P has passed and are prepared for the next toner image formation. In FIG. 1, a transfer band electrode of a corotron is used as the transfer electrode 58. The transfer electrode setting conditions are:
Although it cannot be unconditionally specified because it varies depending on the process speed (peripheral speed) of the photoconductor, for example, the transfer current is +100 to +400 μA, and the transfer voltage is +500.
~ + 2000V can be set value.

On the other hand, the photosensitive drum 50 after separating the recording paper P removes and cleans the residual toner by pressing the blade 621 of the cleaning device (cleaning means) 62.
The pre-charging pre-exposure unit 51 again removes electricity and the charger 52 charges, and the next image forming process starts.

Reference numeral 70 denotes a detachable process cartridge in which a photoconductor, a charging device, a transfer device, a separator and a cleaning device are integrated.

The organic electrophotographic photoconductor of the present invention is generally applied to electrophotographic apparatuses such as electrophotographic copying machines, laser printers, LED printers and liquid crystal shutter type printers. It can be widely applied to devices such as printing, plate making, and facsimile.

[0169]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. In addition, "part" in a sentence represents a mass part.

Preparation of Photoreceptor 1 Photoreceptor 1 was prepared as follows.

The following intermediate layer coating solution was dip-coated on a cylindrical aluminum conductive substrate having a diameter of 80 mm to form an intermediate layer having a dry film thickness of 4.0 μm.

<Intermediate Layer Coating Liquid> Polyamide resin “CM8000” (manufactured by Toray) 10.0 parts Titanium oxide “SMT500SAS” (manufactured by Teika) 30.0 parts Methanol 100.0 parts The above-mentioned circulation type wet disperser ( Day Super Mat SLC12
EX; VMA GETZMANN) was used for dispersion.

<Charge Generating Layer Coating Liquid> Charge generating substance (titanyl phthalocyanine pigment having a maximum peak at a Bragg angle 2θ of 27.2 degrees in X-ray diffraction) 12.0 parts Polyvinyl butyral resin “ESREC BL-1” ( Sekisui Chemical Co., Ltd.) 24.0 parts t-butyl acetate 300.0 parts The above are mixed and dispersed by a sand grinder to prepare a charge generation layer coating liquid, and the charge generation layer coating liquid is immersed on the intermediate layer. By coating, a charge generation layer having a dry film thickness of 0.3 μm was formed.

<Charge Transport Layer Coating Liquid> [4- (2,2-diphenylvinyl) phenyl] -di-p-tolylamine 200.0 parts Polycarbonate "Iupilon Z300" (manufactured by Mitsubishi Gas Chemical Co., Inc.) 300.0 parts 2 , 6-di-t-butyl-4-phenylphenol 5.0 parts 1,2-dichloroethane 2000.0 parts <Surface layer coating solution> (a) solution Polycarbonate (Po-13: viscosity average molecular weight 40,000) 100 parts Compound having a polymerizable functional group (Compound No. 2-1) 30 parts α, α′-azoisobutyronitrile (AIBN) 1 part 1,2-dichloroethane 1200 parts (b) [4- (2,2- Diphenylvinyl) phenyl] -di-p-tolylamine 80 parts 2,6-di-t-butyl-4-phenylphenol 4 parts The above solution (a) is stirred in a nitrogen stream. After reacting under heating and reflux for 6 hours to prepare a coating mother liquor for the surface layer, and then allowing the coating mother liquor to cool, a charge transport substance (b) and an antioxidant are further added to obtain a solid concentration of 10% by mass. The surface layer coating liquid 1 was prepared.

Next, the above charge transport layer coating solution and then the above surface layer coating solution 1 were continuously coated on the charge generation layer by means of a circular slide hopper, followed by heat curing at 110 ° C. for 60 minutes and drying. 4. Charge transport layer with a film thickness of 20 μm and dry film thickness
A 0 μm surface layer was formed.

Preparation of Photoreceptors 2 to 10 In preparation of Photoreceptor 1, the surface of the solution (a) in which the polycarbonate, the compound having a polymerizable functional group, the polymerization initiator, the kind and the amount of the solvent were changed as shown in Table 1 Photoconductors 2 to 1 were prepared in the same manner as the photoconductor 1 except that the layer coating liquids 2 to 10 were prepared and the surface layer coating liquids 2 to 10 were used instead of the surface layer coating liquid 1.
0 was produced.

Preparation of Photoreceptor 11 In preparation of Photoreceptor 1, a photoreceptor 11 was prepared in the same manner as photoreceptor 1 except that the surface layer was not provided and the dry thickness of the charge transport layer was 25 μm.

[0178]

[Table 1]

In the above table, A in the column of polycarbonate
Is exemplified compound Po-13 (viscosity average molecular weight: 40,000), B
Represents an exemplary compound Po-1 (viscosity average molecular weight: 50,000), BPO and AIBN in the polymerization initiator column represent the following compounds BPO: Benzoyl peroxide AIBN: Azobisisobutyronitritri
le Preparation of toner and developer (toner production example 1: example of emulsion polymerization association method) 0.90 kg of sodium n-dodecylsulfate and 10.0 liter of pure water were put and dissolved by stirring. To this solution, 1.20 kg of Regal 330R (Carbon Black manufactured by Cabot Corporation) was gradually added, and after well stirring for 1 hour, the mixture was continuously dispersed for 20 hours using a sand grinder (medium type disperser). This is designated as "colorant dispersion liquid 1".

A solution of 0.055 kg of sodium dodecylbenzenesulfonate and 4.0 liters of ion-exchanged water is referred to as "anionic surfactant solution A".

A solution consisting of 0.014 kg of nonylphenol polyethylene oxide 10 mol adduct and 4.0 liters of ion-exchanged water was designated as "nonionic surfactant solution B".
And

A solution prepared by dissolving 223.8 g of potassium persulfate in 12.0 liters of ion-exchanged water was designated as "initiator solution C".
And

In a GL (glass lining) reactor having a volume of 100 liter equipped with a temperature sensor, a cooling tube, and a nitrogen introducing device, a WAX emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average primary particle size = 12)
3.4 nm (0 nm / solid content concentration = 29.9%), the total amount of “anionic surfactant solution A” and the total amount of “nonionic surfactant solution B” were added, and stirring was started. Next, 44.0 liters of ion-exchanged water was added.

Heating was started, and when the liquid temperature reached 75 ° C., the entire amount of “initiator solution C” was added dropwise. Then, while controlling the liquid temperature to 75 ° C ± 1 ° C, styrene 1
2.1 kg, n-butyl acrylate 2.88 kg, methacrylic acid 1.04 kg and t-dodecyl mercaptan 54
8 g and was added dropwise. After the dropping was completed, the liquid temperature was raised to 80 ° C. ± 1 ° C., and the mixture was heated and stirred for 6 hours. Then, the liquid temperature was cooled to 40 ° C. or lower, stirring was stopped, and filtration was performed with a pole filter to obtain a latex. This is designated as "latex-A".

The resin particles in Latex-A had a glass transition temperature of 57 ° C., a softening point of 121 ° C., a molecular weight distribution of weight average molecular weight = 127,000, and a weight average particle diameter of 12.
It was 0 nm.

A solution prepared by dissolving 0.055 kg of sodium dodecylbenzenesulfonate in 4.0 liters of ion-exchanged pure water is referred to as "anionic surfactant solution D".

A solution prepared by dissolving 0.014 kg of a 10-mol addition product of nonylphenol polyethylene oxide in 4.0 liters of ion-exchanged water is referred to as "nonionic surfactant solution E".

Potassium persulfate (manufactured by Kanto Chemical Co., Inc.) 200.
A solution prepared by dissolving 7 g in 12.0 liters of ion-exchanged water is referred to as "initiator solution F".

In a 100-liter GL reaction kettle equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a comb-shaped baffle, W
AX emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average primary particle size = 120 nm / solid content concentration 29.9%) 3.41 kg, the total amount of "anionic surfactant solution D" and the total amount of "nonionic surfactant solution E" Was added and stirring was started.

Next, 44.0 liters of ion-exchanged water was added. Heating was started, and when the liquid temperature reached 70 ° C., “initiator solution F” was added. Then, a solution prepared by previously mixing 11.0 kg of styrene, 4.00 kg of n-butyl acrylate, 1.04 kg of methacrylic acid and 9.02 g of t-dodecyl mercaptan was added dropwise. After the dropping was completed, the liquid temperature was controlled at 72 ° C. ± 2 ° C., and the mixture was heated and stirred for 6 hours. Furthermore, the liquid temperature was raised to 80 ° C. ± 2 ° C., and the mixture was heated and stirred for 12 hours. The liquid temperature was cooled to 40 ° C. or lower and stirring was stopped. It is filtered with a pole filter, and this filtrate is designated as "latex-B".

The resin particles in Latex-B had a glass transition temperature of 58 ° C., a softening point of 132 ° C., a molecular weight distribution of weight average molecular weight = 245,000 and a weight average particle diameter of 11 ° C.
It was 0 nm.

Sodium chloride as a salting-out agent 5.36k
A solution prepared by dissolving g in 20.0 liters of ion-exchanged water is referred to as “sodium chloride solution G”.

A solution prepared by dissolving 1.00 g of a fluorine-based nonionic surfactant in 1.00 liter of ion-exchanged water is referred to as "nonionic surfactant solution H".

In a 100-liter SUS reactor equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a particle size and shape monitoring device (the reaction device having the configuration shown in FIG. 3, the crossing angle α is 25 °), Latex-A = 2
0.0 kg, latex-B = 5.2 kg, colorant dispersion 1 = 0.4 kg, and ion-exchanged water 20.0 kg were added and stirred. Then, the mixture was heated to 40 ° C., sodium chloride solution G, isopropanol (Kanto Chemical Co., Ltd.) 6.00 k
g and nonionic surfactant solution H were added in this order. Then, after leaving it for 10 minutes, the temperature rise is started and the liquid temperature becomes 8
The temperature was raised to 5 ° C. in 60 minutes, and heated and stirred at 85 ± 2 ° C. for 0.5 to 3 hours to grow the particle size while salting out / fusing.
Next, 2.1 liters of pure water was added to stop the particle size growth to prepare a fused particle dispersion liquid.

A 5 liter reaction vessel equipped with a temperature sensor, cooling tube, particle size and shape monitoring device (see FIG. 3).
5.0 kg of the fused particle dispersion liquid prepared above was placed in a reactor having a structure shown in FIG.
The shape was controlled by heating and stirring at 5 ° C ± 2 ° C for 0.5 to 15 hours. Then, it cooled to 40 degrees C or less, and stopped stirring.
Next, using a centrifuge, classification is performed in the liquid by a centrifugal sedimentation method, and the mixture is filtered through a sieve having an opening of 45 μm to obtain the filtrate as an association liquid. Then, using a Nutsche filter, wet cake-like non-spherical particles were collected from the association liquid by filtration. afterwards,
It was washed with ion-exchanged water. The non-spherical particles were dried at a suction temperature of 60 ° C. using a flash jet dryer, and then at a temperature of 60 ° C. using a fluidized bed dryer. To 100 parts by mass of the obtained colored particles, 1 part by mass of silica fine particles was externally added and mixed by a Henschel mixer to obtain a toner by an emulsion polymerization association method.

In the monitoring of the salting out / fusion step and the shape control process, the stirring rotation speed and the heating time were controlled to control the shape and the coefficient of variation of the shape coefficient, and further, the particle size was classified by the in-liquid classification. And toners 1 to 1 composed of toner particles having the shape characteristics and the particle size distribution characteristics shown in Table 2 by arbitrarily adjusting the variation coefficient of the particle size distribution.
Got 7.

[0197]

[Table 2]

[Production of Developer] Toners 1 to 17
Developers 1 to 17 for evaluation were manufactured by mixing 0 parts by mass and 100 parts by mass of a 45 μm ferrite carrier coated with a styrene-methacrylate copolymer.

Evaluation The photoconductors 1 to 11 and the developers 1 to 17 were combined as shown in Table 3, and as an evaluation machine, a digital copying machine Ko manufactured by Konica Corporation was used.
Nica "Sitios 7075" (corona charging, laser exposure, reversal development, electrostatic transfer, nail separation, blade cleaning, cleaning auxiliary brush roller adoption process, printing speed 75 sheets / min) was used for evaluation. The cleaning property and the image evaluation were carried out by copying an original image in which a character image having a pixel ratio of 7%, a human face photograph, a solid white image, and a solid black image are each divided into quarters on A4 neutral paper. The copying conditions were evaluated by performing continuous copying of 200,000 sheets in a high temperature and high humidity environment (30 ° C., 80% RH) which seems to be the most severe. However, before the start of copying, the surface of the photoconductor was sprinkled with setting powder, the photoconductor and the cleaning blade were allowed to conform, and 200,000 copies were made.
The evaluation items and evaluation criteria are shown below.

[0200]

[Table 3]

Evaluation Items and Evaluation Standard Image Density (Measured using RD-918 manufactured by Macbeth Co.).
The relative reflection density was measured with the reflection density of the paper being "0".
(Evaluated both at the initial stage and after 200,000 copies) ◎: 1.2 or higher at both the initial stage and after 200,000 copies: Good ○: 1.0 or higher at both the initial stage and after 200,000 copies: No problem in practical use × : At least one of the initial stage and at least one after 200,000 copies is less than 1.0: Level fog which is a problem in practical use: Judgment based on solid white image density Copy sheet not printed using Macbeth reflection densitometer "RD-918" ( The density of a blank sheet) is measured at 20 locations with absolute image densities, and the average value is taken as the blank sheet density. Next, the white background portion of the evaluation sheet on which the image was formed
Absolute image density was measured at 0 places, and the value obtained by subtracting the blank paper density from the average density was evaluated as the fog density.

⊚: 0.005 or less (good) both at the initial stage and after 200,000 copies ◯: 0.01 or less at both the initial stage and after 200,000 copies (no practical problem) ×: Initial stage and 200,000 copies At least one of the latter is 0.01
Larger (obviously, there is a problem in practical use) Resolution (determined by the ease of distinguishing character images) ◎: There is no difference in the resolution between the initial and 200,000 copies ○: Halftone images have a slight resolution after 200,000 copies There is a significant decrease x: There is a significant decrease in resolution after 200,000 copies Toner transfer rate The transfer rate (%) was determined by the following formula. However, when obtaining the transfer rate, the toner collected from the cleaning unit was not returned to the developing device but was taken in a bag.

Transfer rate (%) = {1- (mass of collected toner / mass of consumed toner)} × 100 Cleaning property (A3 after completion of 100,000 and 200,000 copies)
10 sheets are continuously copied on paper, and it is judged by the presence or absence of defective cleaning in solid white areas. ◎: No toner slipping up to 200,000 sheets ○: No toner slipping up to 100,000 sheets ×: 100,000 sheets Toner slip-through occurs below ◎: No occurrence up to 200,000 sheets ○: Minor blade squeal occurs when the drum is stopped ×: Blade squeal occurs during cleaning operation Other evaluation conditions In addition, other evaluation conditions using Sitios 7075 are as follows: The following conditions were set.

Charging conditions Charging device: Scorotron charger, initial charging potential of -750
V exposure condition Set the exposure amount to make the exposed portion potential -50V.

Development condition DC bias; -550V Transfer condition Transfer pole; Corona charging method Cleaning condition Hardness 70 °, impact resilience 65%, thickness 2 in cleaning part
(Mm) and a cleaning blade having a free length of 9 mm were brought into contact with each other by a weight load method in the counter direction so as to have a linear pressure of 18 (N / m).

The evaluation results are shown in Table 4.

[0207]

[Table 4]

As is clear from Table 4, combinations 1 to 16 and 18 using the electrophotographic photosensitive member of the present invention and a toner were used.
26 to 26 are compared with the combinations 17 (toner is not the invention), 27 (photoreceptor is not the invention) and 28 (toner and photoreceptor are not the invention) other than the invention, image density, resolution, toner transfer rate. It is found that the characteristics such as cleaning property and blade squeal are excellent.

[0209]

As is apparent from the above examples, the image forming method satisfying the conditions of the present invention is
It is possible to form a sharp electrophotographic image having excellent cleaning properties and no image unevenness.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram of an example of an image forming apparatus of the present invention.

FIG. 2A is an explanatory diagram showing projected images of toner particles having no corners, and FIGS. 2B and 2C are explanatory diagrams showing projected images of toner particles having corners.

FIG. 3 is a perspective view showing an example of a polymerized toner reaction device.

FIG. 4 is a cross-sectional view showing an example of a polymerized toner reaction device.

FIG. 5 is a schematic view showing a specific example of the shape of a stirring blade.

[Explanation of symbols]

50 photoconductor drum (or photoconductor) 51 Pre-charge exposure unit 52 Charger 53 Image exposure device 54 Developer 541 Development sleeve 543,544 developer stirring and conveying member 547 potential sensor 57 Paper Feed Roller 58 transfer electrode 59 Separation electrode (separator) 60 fixing device 61 Paper ejection roller 62 cleaning device 70 Process cartridge

Claims (13)

[Claims] 1. A latent image formed on an electrophotographic photosensitive member having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group has a variation coefficient of shape factor of toner particles. An image forming method comprising developing with a developer using a toner having a content of 16% or less. 2. A latent image formed on an electrophotographic photoreceptor having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group has a shape factor of 1.2.
An image forming method comprising: developing with a developer using a toner containing 65% by number or more of toner particles in the range of from 1.6 to 1.6. 3. A latent image formed on an electrophotographic photosensitive member having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group is 50% by number of toner particles having no corners. An image forming method comprising developing with a developer using the toner contained above. 4. A latent image formed on an electrophotographic photosensitive member having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group, the toner image having a particle size of D ( μm), the natural logarithm lnD is taken as the horizontal axis, and the horizontal axis is divided into a plurality of classes at 0.23 intervals. The relative frequency of toner particles included in the most frequent class in the histogram showing the number-based particle size distribution ( m ₁ ) and the relative frequency (m ₂ ) of the toner particles contained in the second most frequent class, the sum (M) of which is 70% or more. And an image forming method. 5. A latent image formed on an electrophotographic photosensitive member having a surface layer containing a binder resin and a polymer formed of a compound having a polymerizable functional group has a toner particle number variation coefficient of 27. % Of the toner or less is used to develop with an image forming method. 6. The image forming method according to claim 1, wherein the compound having a polymerizable functional group is a vinyl monomer represented by the following general formula (1). [Chemical 1] (In the general formula (1), R _{1 to} R ₃ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, X is —O—, —COO—, or —CONH—, and R ₄ is 5 to 5 carbon atoms. 20 alkyl groups are shown) 7. The image forming method according to claim 1, wherein the compound having a polymerizable functional group is a vinyl monomer represented by the following general formula (2). [Chemical 2] (In the general formula (2), R _{5 to} R ₇ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, X is —O—, —COO—, or —CONH—, and Rf is a fluorinated alkyl group. (Indicates an alkyl group containing 5 to 20 carbon atoms) 8. The image forming method according to claim 1, wherein the binder resin contains a polycarbonate having a siloxane partial structure as a main component. 9. The image forming method according to claim 1, wherein the polymer formed from the compound having a polymerizable functional group is in a phase separation state with a binder resin. 10. The polymer formed from the compound having a polymerizable functional group is formed by dispersion polymerization in a solution in which a binder resin is dissolved.
9. The image forming method according to any one of 9 above. 11. The image forming method according to claim 1, wherein the toner is a polymerized toner. 12. The number average particle diameter of the toner is from 3.0 to
It is 8.5 micrometers, The image forming method of any one of Claims 1-11 characterized by the above-mentioned. 13. An image forming apparatus, which forms an electrophotographic image by using the image forming method according to claim 1. Description: