JP2002251032A - Toner for developing electrostatic charge image, latent image carrier, and image forming method and device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of forming good-quality images for many sheets by using low-temperature fixing toner. SOLUTION: This image forming device is provided with at least a latent image carrier, and a developing means developing the electrostatic latent image formed on the image carrier with toner. The latent image carrier incorporates filler in its outermost layer, and the toner is constituted by externally adding inorganic particulates to toner base particles, and the number average molecular weight (Mn) of the binding resin of the toner base particles is <=3000, and molecules whose molecular weight is <=1000 are >=40%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge used for developing an electrostatic latent image formed on the surface of a latent image carrier in, for example, electrophotography, electrostatic recording, electrostatic printing, and the like. The present invention relates to an image developing toner, the latent image carrier, an image forming method using the toner and the latent image carrier, and an image forming apparatus.

[0002]

2. Description of the Related Art In a copying machine, a printer, a facsimile, and the like using an electrophotographic process, an organic photoconductor is often used as a latent image carrier. The organic photoreceptor is provided with a photosensitive layer on a conductive support directly or via an undercoat layer. In particular, the photosensitive layer is formed by laminating a charge generation layer and a charge transport layer. Are the mainstream.

On the other hand, an electrostatic latent image formed on a latent image carrier is visualized by an electrostatic image developing toner (hereinafter, also referred to as toner) containing a colorant and a binder resin as main components.
The toner image is fixed as it is or, if necessary, the toner image is transferred and fixed on a transfer material. Examples of the developer used for the development include a two-component developer composed of a carrier and a toner, and a one-component developer composed of only a toner without using a carrier.

[0004] In recent years, in response to the trend of energy saving, movements corresponding to energy saving have been active in the field of electrophotography and the like. Especially in the electrophotographic equipment, the power consumption is large in the fixing section, and the mechanism has been devised to save power, but the toner equivalent to the supply has been developed for the energy-saving fixing device. Is imminent.

The toner corresponding to the energy-saving fixing device is, after all, a toner having a good low-temperature fixing property, and the conventionally known low-temperature fixing toner has been devised as a binder resin in various ways. It is a thing using a thing. However, such a toner has a disadvantage that the powder fluidity is remarkably inferior, so that the supply and replenishment to the developing area or the developing section is not performed smoothly.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner which can save energy of a fixing device. Another object of the present invention is to provide a latent image carrier, an image forming method, and an image forming apparatus suitable for forming an image using the toner exhibiting good low-temperature fixability.

[0007]

Means for Solving the Problems The present inventors have again studied the low-temperature fixability of toner. as a result,
In particular, when the binder resin for the toner contains a large amount of low molecular weight components, the powder fluidity of the toner is remarkably inferior to that of the conventional toner, so that more inorganic fine particles as a fluidity improver must be externally added. However, even if a large amount of inorganic fine particles are externally added, the toner main body (toner base particles) itself is soft. There is a problem that the inorganic fine particles are buried in the toner main body and the powder fluidity is immediately deteriorated.

The problem of powder fluidity can be improved by devising a binder resin for toner and by increasing the external addition amount of inorganic fine particles far more than before. But,
Increasing the external addition amount of the inorganic fine particles in the toner has a side effect that the surface of the latent image carrier is easily shaved. In the case of the latent image carrier, if the photosensitive layer is scraped, the photosensitivity becomes slow, and the potential of the exposed portion does not drop as much as in the initial stage, so that there is a problem that the image density does not appear in negative-positive development.

As a result of further studies, the present inventors have found that the number average molecular weight (M
n) is 3000 or less and 4 or less molecules having a molecular weight of 1000 or less.
0% by number or more and the external addition amount of inorganic fine particles is 1.0%
According to the image forming method / apparatus using a material having a weight percent or more and using a material containing a filler in the outermost layer as a latent image carrier, the latent image carrier has less film scraping and is used repeatedly. Also confirmed that a stable image density was obtained. The present invention has been made based on this.

Therefore, according to the present invention, first, a toner used in the developing step in an image forming method and an image forming apparatus for forming an image on a transfer material through at least steps of charging, exposing, developing, and transferring. The number average molecular weight (M
n) is 3000 or less and 4 or less molecules having a molecular weight of 1000 or less.
There is provided a toner for developing an electrostatic image, wherein inorganic fine particles are externally added in an amount of 1.0% by weight or more to 0% by number or more of toner base particles.

Second, an image is formed on a transfer material through at least steps of charging, exposing, developing, and transferring.
And the toner used in the developing step has a number average molecular weight (M
n) is 3000 or less and 4 or less molecules having a molecular weight of 1000 or less.
A latent image carrier used in an image forming method and an image forming apparatus, which is a toner obtained by externally adding 1.0% by weight or more of inorganic fine particles to toner base particles of 0% by number or more, and the outermost layer of the latent image carrier Contains a filler.

Third, at least a charging step, an exposure step,
In an image forming method comprising forming an image on a transfer material through a development step and a transfer step, the toner used in the development step has a number average molecular weight (Mn) of 3000 or less and 40% by number of molecules having a molecular weight of 1000 or less. An image forming method is provided, wherein the toner is obtained by externally adding 1.0% by weight or more of inorganic fine particles to the toner base particles, and the latent image carrier used contains a filler in the outermost layer.

Fourth, in an image forming apparatus for forming an image on a transfer material through at least a charging unit, an exposing unit, a developing unit, and a transferring unit, the toner used in the developing step has a number average molecular weight (Mn). The toner is a toner obtained by externally adding 1.0% by weight or more of inorganic fine particles to toner base particles having a number of molecules of not more than 3000 and not more than 40% by number of molecules having a molecular weight of not more than 1000, and the latent image carrier used contains a filler in the outermost layer An image forming apparatus is provided.

The effect of the low-temperature fixability of the toner of the present invention on the low-temperature fixability is most affected by the molecular weight of 1 on the number distribution of the toner molecular weight.
000 or less, and in particular, when the number of molecules having a molecular weight of 1000 or less is 40% by number or more, several tens of
° C low-temperature fixability is obtained. However, this toner needs to have a number average molecular weight (Mn) of 3000 or less. When the number average molecular weight (Mn) exceeds 3,000, the toner contains a considerable amount of high molecular weight components, so that a sharp molecular weight distribution of one peak cannot be obtained and a toner having a sharp melt cannot be obtained. The amount of the inorganic fine particles externally added to the toner base particles was 1.0% by weight.
As described above, the upper limit is about 3.0% by weight because the base surface is encapsulated by hard inorganic fine particles and fixability is impaired.

Although the reason why the wear resistance of the latent image carrier is maintained even when the toner containing a large amount of the above-mentioned inorganic fine particles is used is not clear, the following mechanism is considered. In other words, it is an image in which there are many islands of relatively hard filler in the sea of the soft protective layer, and external impact that causes shaving is first received by the hard filler, and then the impact force of the filler is It is alleviated by the resin of the surrounding soft protective layer.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. As described above, the toner of the present invention is obtained by externally adding inorganic fine particles to toner base particles containing a colorant and a binder resin as main components. The toner used here has a number-average molecular weight (Mn) of 3,000 or less and molecules having a molecular weight of 1000 or less at 40% by number or more, and the amount of inorganic fine particles added is 1.0% by weight or more, preferably 1.2% by weight. ~ 2.0% by weight. This toner may be used as a one-component developer without using a carrier, or as a two-component developer used with a carrier.

It is preferable to use a polyester resin as the binder resin. This polyester resin is obtained by polycondensation of an alcohol and a carboxylic acid. Here, the glass transition temperature Tg of the polyester resin is preferably 55 ° C. or more, more preferably 60 ° C. or more, from the viewpoint of heat storage properties.

Examples of the alcohol used include glycols such as ethylene glycol, diethylene glycol, triethylene glycol and propylene glycol, etherified bisphenols such as 1,4-bis (hydroxymethyl) cyclohexane and bisphenol A, and other alcohols. Examples thereof include a monohydric alcohol monomer and a trihydric or higher polyhydric alcohol monomer.

Examples of the carboxylic acid include divalent organic acid monomers such as maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid and malonic acid;
1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane, 1,
Examples thereof include trivalent or higher polyvalent carboxylic acid monomers such as 2,7,8-octanetetracarboxylic acid.

In the present invention, as the resin component (binder resin for toner) in the toner, a resin other than the polyester resin can be used in combination as long as the performance of the toner is not impaired. In this case, examples of usable resins include the following, but are not limited thereto.

Polystyrene, chloropolystyrene, polyα-methylstyrene, styrene / chlorostyrene copolymer, styrene / propylene copolymer, styrene / butadiene copolymer, styrene / vinyl chloride copolymer, styrene / vinyl acetate copolymer Copolymer, styrene / maleic acid copolymer, styrene / acrylate copolymer (styrene / methyl acrylate copolymer, styrene / ethyl acrylate copolymer, styrene / butyl acrylate copolymer,
Styrene / octyl acrylate copolymer, styrene / phenyl acrylate copolymer, etc., styrene / methacrylic ester copolymer (styrene / methyl methacrylate copolymer, styrene / ethyl methacrylate copolymer, styrene / methacrylic) Styrene resin (styrene or styrene substituted product) such as butyl acrylate copolymer, styrene / phenyl methacrylate copolymer, etc., styrene / α-methyl methacrylate copolymer, styrene / acrylonitrile / acrylate copolymer, etc. A homopolymer or copolymer), vinyl chloride resin, styrene / vinyl acetate copolymer, rosin-modified maleic resin, phenolic resin, epoxy resin, polyethylene resin, polypropylene resin, ionomer resin, polyurethane resin, silicone resin,
Ketone resin, ethylene / ethyl acrylate copolymer,
Petroleum resins and hydrogenated petroleum resins such as xylene resin and polyvinyl butyral resin.

These resins are not limited to single use, but may be used in combination of two or more. In addition, the production method is not particularly limited, and any of bulk polymerization, solution polymerization, emulsion polymerization, and suspension polymerization can be used.

Examples of the coloring agent include carbon black, lamp black, iron black, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G, rhodamine 6C lake, calco oil blue, chrome yellow, quinacridone, benzidine yellow, rose bengal, Any conventionally known dye or pigment such as a triallylmethane dye or the like can be used alone or in combination, and can be used as a black toner or a full-color toner. The amount of these colorants used is usually 1 to 30% by weight, preferably 3% by weight, based on the toner resin component.
-20% by weight.

The toner base particles optionally contain a charge control agent. As the charge control agent, any conventionally known polarity control agents such as a nigrosine dye, a metal complex type dye, and a quaternary ammonium salt can be used alone or in combination. The amount of the polarity controlling agent used is 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on the toner resin component.

The toner base particles of the present invention may be mixed with any conventionally known release agent such as carnauba wax, montan wax, rice oxide oxide, solid silicone varnish, higher fatty acid higher alcohol and low molecular weight polypropylene wax. Can be used. In particular, use of carnauba wax of a free fatty acid type is preferred. The carnauba wax is preferably a microcrystalline wax, and preferably has an acid value of 5 or less and a particle diameter of 1 μm or less when dispersed in a toner resin component. The addition amount of these release agents to the toner base particles is preferably 1 to 20% by weight, more preferably 3 to 10% by weight.

As the inorganic fine particles (fluidity improver), any conventionally known fluidity improvers such as silicon oxide, titanium oxide, silicon carbide, aluminum oxide and barium titanate can be used alone or in combination. The average size of the inorganic fine particles is suitably from 0.005 to 0.2 μm, and preferably from 0.01 to 0.1 μm. If the average particle size is larger than 0.2 μm, the fluidity of the toner becomes poor,
From the charging failure to the toner scattering occurs. On the other hand, when the average particle size is smaller than 0.005 μm, the toner base particles are easily embedded in the resin surface, and the fluidity does not function. These inorganic fine particles are used in an amount of 1.0 to 3.0 parts by weight based on 100 parts by weight of the toner base particles.
Preferably it is 0.5 to 2 parts by weight.

Next, the latent image carrier (hereinafter sometimes referred to as an electrophotographic photosensitive member or a photosensitive member) of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view illustrating an electrophotographic photosensitive member used in the present invention.
A single-layer photosensitive layer 33 containing a charge generating substance and a charge transporting substance as main components is provided, and a protective layer 39 is provided on the photosensitive layer.

FIG. 2 is a cross-sectional view showing another example of the structure of the electrophotographic photosensitive member used in the present invention. The photosensitive layer comprises a charge generating layer 35 mainly composed of a charge generating substance and a charge transporting substance. It has a configuration in which a charge transport layer 37 as a main component is laminated, and a protective layer 39 is provided on the charge transport layer 37.

FIG. 3 is a cross-sectional view showing still another configuration example of the electrophotographic photosensitive member used in the present invention. The photosensitive layer comprises a charge transport layer 37 mainly composed of a charge transport substance and a charge generation substance. It has a configuration in which a charge generation layer 35 as a main component is laminated, and a protective layer 39 is provided on the charge generation layer 35.

The conductive support 31 has a volume resistance of 10
Those exhibiting a conductivity of ¹⁰ Ωcm or less, for example, aluminum, nickel, chromium, nichrome, copper, gold, silver, metals such as platinum, tin oxide, metal oxides such as indium oxide, by evaporation or sputtering, Film or cylindrical plastic or paper coated or plates made of aluminum, aluminum alloy, nickel, stainless steel, etc., and extruded, drawn, etc., made into a tube, then cut, super finished, polished, etc. And the like can be used. Further, an endless nickel belt and an endless stainless belt disclosed in JP-A-52-36016 can also be used as the conductive support 31.

In addition to the above, a support obtained by dispersing a conductive powder in a suitable binder resin on the above support and applying the same can also be used as the conductive support 31 of the present invention.

Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc and silver, and metal oxide powder such as conductive tin oxide and ITO. And so on.

The binder resins used simultaneously include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate. Copolymer, polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal,
Polyvinyl toluene, poly-N-vinyl carbazole,
Thermoplastic, thermosetting or photocurable resins such as acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin, and alkyd resin.

Such a conductive layer can be provided by dispersing the conductive powder and the binder resin in an appropriate solvent, for example, tetrahydrofuran, dichloromethane, methyl ethyl ketone, toluene, or the like, and applying the dispersion.

Further, heat shrinkage of a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) or the like containing the conductive powder on a suitable cylindrical substrate. Also those that have a conductive layer provided by a tube,
It can be used favorably as the conductive support 31 of the present invention.

Next, the photosensitive layer will be described. The photosensitive layer may be a single layer or a laminate, but for convenience of explanation, the case where the photosensitive layer is composed of the charge generation layer 35 and the charge transport layer 37 will be described first.

The charge generation layer 35 is a layer containing a charge generation substance as a main component, and may use a binder resin as needed. As the charge generation substance, an inorganic material and an organic material can be used.

Examples of the inorganic material include crystalline selenium, amorfasselen, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compound, amorphous silicon, and the like. As amorphous silicon, a material obtained by terminating a dangling bond with a hydrogen atom or a halogen atom, or a material doped with a boron atom, a phosphorus atom, or the like is preferably used.

On the other hand, as the organic material, a known material can be used. For example, phthalocyanine pigments such as metal phthalocyanine and non-metal phthalocyanine, azulhenium salt pigment, methine squaric acid pigment, azo pigment having a carbazole skeleton, azo pigment having a triphenylamine skeleton, azo pigment having a diphenylamine skeleton, dibenzothiophene skeleton Azo pigment having a fluorenone skeleton, azo pigment having an oxadiazole skeleton, azo pigment having a bisstillene skeleton, azo pigment having a distyryl oxadiazole skeleton, azo pigment having a distyryl carbazole skeleton, perylene Pigments, anthraquinone or polycyclic quinone pigments, quinone imine pigments, diphenylmethane and triphenylmethane pigments, benzoquinone and naphthoquinone pigments, cyanine and azomethine pigments, i Jigoido based pigments, and bisbenzimidazole pigments. These charge generating substances can be used alone or as a mixture of two or more kinds.

Among them, azo pigments and / or phthalocyanine pigments are effectively used. In particular, the following structural formula (A)
Azo pigments represented by the following formulas, and titanyl phthalocyanine (particularly, a diffraction peak (± 0.2 °) at a Bragg angle 2θ with respect to characteristic X-rays (wavelength 1.541 °) of CuKα:
Titanyl phthalocyanine having a maximum diffraction peak at least at 27.2 ° can be effectively used.

Embedded image (In the formula, Cp ₁ and Cp ₂ represent a coupler residue and may be the same or different. In particular, when Cp ₁ and Cp ₂ are different, very high photocarrier generation efficiency (high sensitivity) may be exhibited. R ₂₀₁ and R ₂₀₂ each represent any one of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, and a cyano group. Cp ₁ and Cp ₂ are represented by the following formula (B).

Embedded image (Wherein, R ₂₀₃ represents a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group.
₂₀₄ , R ₂₀₅ , R ₂₀₆ , R ₂₀₇ , and R ₂₀₈ each represent a hydrogen atom, a nitro group, a cyano group, a halogen atom such as fluorine, chlorine, bromine, or iodine, or an alkyl group such as a trifluoromethyl group, a methyl group, or an ethyl group. Group, a methoxy group, an alkoxy group such as an ethoxy group, a dialkylamino group, a hydroxyl group, and Z represents a group of atoms necessary to constitute a substituted or unsubstituted aromatic carbocyclic ring or a substituted or unsubstituted aromatic heterocyclic ring. Is preferable. )

If necessary, the binder resin used for the charge generation layer 35 includes polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicon resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, Poly-N-vinyl carbazole, polyacrylamide, polyvinyl benzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinyl pyridine, cellulose resin, casein, polyvinyl alcohol, polyvinyl And pyrrolidone.
The amount of the binder resin is 0 to 100 parts by weight of the charge generating substance.
500 parts by weight, preferably 10 to 300 parts by weight, is suitable.

As a method for forming the charge generation layer 35, a vacuum thin film preparation method and a casting method from a solution dispersion system can be used.

The former method for producing a vacuum thin film includes a vacuum evaporation method,
A glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, a CVD method, or the like is used, and the above-mentioned inorganic material and organic material can be favorably formed as the charge generation layer 35.

In order to form a charge generation layer by the casting method described below, the above-mentioned inorganic or organic charge generation material is used together with a binder resin, if necessary, using a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, butanone. It can be formed by dispersing with a ball mill, an attritor, a sand mill, or the like, diluting the dispersion liquid appropriately, and applying. For the application, a method such as dip coating, spray coating, bead coating nozzle coating, spinner coating, and ring coating can be used.

The thickness of the charge generation layer 35 is 0.01 to 5 μm.
m is appropriate, and preferably 0.1 to 2 μm.

The charge transport layer 37 is formed by dissolving or dispersing a charge transport material and a binder resin in an appropriate solvent,
It can be formed by drying.

The charge transport material includes an electron transport material and a hole transport material.

Examples of the electron transporting substance include chloranil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4,5,7-tetranitroxanthone, 2,
4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophene-4
-One, 1,3,7-trinitrodibenzothiophene-
Electron accepting substances such as 5,5-dioxide and benzoquinone derivatives are exemplified.

Examples of the hole transport material include poly-N-vinylcarbazole and its derivatives, poly-γ-carbazolylethylglutamate and its derivatives, pyrene-formaldehyde condensate and its derivatives, polyvinylpyrene, polyvinylphenanthrene, polysilane, Oxazole derivatives, oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives,
α-phenylstilbene derivative, benzidine derivative, diarylmethane derivative, triarylmethane derivative, 9
-Other known materials such as styryl anthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, bisstilbene derivatives, enamine derivatives and the like.

These charge transporting substances are used alone or in combination of two or more.

Examples of the binder resin include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, and polystyrene. Vinyl acetate, polyvinylidene chloride, polyalate, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane Thermoplastic or thermosetting resins such as resin, phenolic resin, and alkyd resin are exemplified.

The amount of the charge transporting substance is 20 to 300 parts by weight, preferably 40 to 150 parts by weight, per 100 parts by weight of the binder resin.
Parts by weight are appropriate.

The thickness of the charge transport layer is preferably about 5 to 100 μm. Further, as a solvent used for forming the charge transport layer, tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, acetone, and the like are used, and these may be used alone or in combination of two or more. May be used.

As described above, when the charge transport layer is the outermost layer of the photoreceptor, the surface portion of the charge transport layer contains a filler for the purpose of improving abrasion resistance. This charge transport layer is distinguished from the electrophotographic photosensitive member having the protective layer 39 shown in FIG. 2 because the filler exists together with the charge transport material.

Filler materials added for the purpose of improving the abrasion resistance of the photoreceptor include organic fillers and inorganic fillers. Examples of the organic filler material include fluororesin powder such as polytetrafluoroethylene, silicone resin powder, and a-carbon powder.Examples of the inorganic filler material include copper, tin, aluminum, and metal powder such as indium. Metal oxides such as silica, tin oxide, zinc oxide, titanium oxide, alumina, zirconium oxide, indium oxide, antimony oxide, bismuth oxide, calcium oxide, antimony-doped tin oxide, tin-doped indium oxide, and tin fluoride , Calcium fluoride, metal fluoride such as aluminum fluoride, potassium titanate,
An inorganic material such as boron nitride may be used. Among these fillers, it is advantageous to use an inorganic material from the viewpoint of the hardness of the filler for improving wear resistance.

Further, as the filler which does not easily cause image blur, a filler having high electric insulation is preferable, and a filler having a pH of 5 or more and a dielectric constant of 5 or more are preferable.
Those described above are particularly effective, and titanium oxide, alumina, zinc oxide, zirconium oxide and the like can be particularly effectively used. In addition, a filler having a pH of 5 or more or a filler having a dielectric constant of 5 or more can be used alone.
A filler having an H of 5 or less and a filler having a pH of 5 or more are mixed with 2
It is also possible to use a mixture of two or more kinds, or a mixture of two or more kinds of fillers having a dielectric constant of 5 or less and fillers having a dielectric constant of 5 or more. In addition, among these fillers, α-alumina, which has high insulation properties, high thermal stability, and high abrasion resistance, has a hexagonal close-packed structure, is used to suppress image blur and improve abrasion resistance. Particularly useful.

Further, these fillers can be surface-treated with at least one kind of surface treatment agent, and it is preferable to do so from the viewpoint of dispersibility of the filler. The decrease in the dispersibility of the filler not only increases the residual potential, but also causes a decrease in the transparency of the coating film, the occurrence of coating film defects, and a decrease in abrasion resistance, which hinders high durability or high image quality. It can evolve into a big problem.

As the surface treatment agent, any of the conventionally used surface treatment agents can be used, but a surface treatment agent capable of maintaining the insulating property of the filler is preferable. For example,
Titanate-based coupling agents, aluminum-based coupling agents, zirco-aluminate-based coupling agents, higher fatty acids, etc., or a mixture treatment thereof with a silane coupling agent, Al ₂ O ₃ , TiO ₂ , ZrO ₂ , silicone,
Aluminum stearate or the like or a mixture thereof is more preferable from the viewpoint of filler dispersibility and image blur. Although the treatment with the silane coupling agent has a strong effect of image blur, the effect of mixing the surface treatment agent and the silane coupling agent may be suppressed in some cases.

The amount of surface treatment varies depending on the average primary particle size of the filler used, but 2 to 30% by weight is suitable, and 3 to 20% by weight is more preferable. If the amount of the surface treatment is smaller than this, the effect of dispersing the filler cannot be obtained, and if the amount is too large, the residual potential is significantly increased.

The average primary particle size of the filler is 0.0
The thickness is preferably 1 to 0.5 μm from the viewpoint of the light transmittance and abrasion resistance of the protective layer. The average primary particle size of the filler is 0.0
When it is 1 μm or less, abrasion resistance and dispersibility may be reduced, and when it is 0.5 μm or more, sedimentation of the filler may be promoted or an abnormal image may be generated.

For the charge transport layer, a high molecular charge transport material having both a function as a charge transport material and a function as a binder resin is preferably used. The charge transport layer composed of these high-molecular charge transport materials is excellent in film-forming properties because it is a polymer compound itself, and has a higher density of charge transport sites than the charge transport layer composed of a low-molecular-weight dispersed polymer. It can be configured and has excellent charge transport ability. For this reason, a photoreceptor having a charge transport layer using a polymer charge transport material can be expected to have high-speed response.

As the polymer charge transporting substance, known materials can be used, and particularly, a polycarbonate containing a triarylamine structure in a main chain and / or a side chain is preferably used. Among them, the polymer charge transport materials represented by the formulas (I) to (X) are preferably used, and these are exemplified below and specific examples are shown.

[0063]

Embedded image[Wherein, R₁, R_Two, R_ThreeAre each independently substituted or
Is an unsubstituted alkyl group or halogen atom, R_FourIs hydrogen field
Or a substituted or unsubstituted alkyl group, R_Five, R ₆Is
Substituted or unsubstituted aryl groups, o, p and q are each
Independently, integers of 0 to 4, k and j represent compositions (molar fractions).
And represents a number of 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9, and n is
It represents the number of repeating units and is an integer of 5 to 5000. X is
Aliphatic divalent group, cycloaliphatic divalent group, or the following general
Represents a divalent group represented by the formula:

Embedded image (In the formula, R ₁₀₁ and R ₁₀₂ each independently represent a substituted or unsubstituted alkyl group, aryl group or halogen atom. L and m are integers of 0 to 4, Y is a single bond, and has 1 carbon atom.
~ 12 linear, branched or cyclic alkylene groups,
-O -, - S -, - SO -, - SO 2 -, - CO -, -
CO—O—Z—O—CO— (Z represents an aliphatic divalent group) or

Embedded image (A is an integer of 1 to 20, b is an integer of 1 to 2000, R
₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or an aryl group). Here, R ₁₀₁ and R _102, R _{10 3} and R ₁₀₄ may be the same or different. ]

[0064]

Embedded image (Wherein R ₇ and R ₈ are a substituted or unsubstituted aryl group,
Ar ₁ , Ar ₂ and Ar ₃ represent the same or different arylene groups. X, k, j and n are the same as in the case of the general formula (I). )

[0065]

Embedded image (Wherein, R ₉ and R ₁₀ represent a substituted or unsubstituted aryl group, and Ar ₄ , Ar ₅ and Ar ₆ represent the same or different arylene groups. X, k, j and n represent the general formula (I) Same as case.)

[0066]

Embedded image (In the formula, R ₁₁ and R ₁₂ represent a substituted or unsubstituted aryl group, Ar ₇ , Ar ₈ , and Ar ₉ represent the same or different arylene groups, and p represents an integer of 1 to 5. X, k, j And n
Is the same as in the case of the general formula (I). )

[0067]

Embedded image(Where R₁₃, R₁₄Is a substituted or unsubstituted aryl
Group, Ar_Ten, Ar₁₁, Ar ₁₂Are the same or different allylenes
Group, X₁, X_TwoIs a substituted or unsubstituted ethylene group, or
Represents a substituted or unsubstituted vinylene group. X, k, j
And n are the same as in the case of the general formula (I). )

[0068]

Embedded image (Wherein R ₁₅ , R ₁₆ , R ₁₇ and R ₁₈ are substituted or unsubstituted aryl groups, Ar ₁₃ , Ar ₁₄ , Ar ₁₅ and Ar ₁₆ are the same or different arylene groups, Y ₁ , Y ₂ and Y ₃ Represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, and a vinylene group, and may be the same or different. X, k, j and n are
This is the same as in the case of the general formula (I). )

[0069]

Embedded image (Wherein, R ₁₉ and R ₂₀ represent a hydrogen atom or a substituted or unsubstituted aryl group, and R ₁₉ and R ₂₀ may form a ring. Ar ₁₇ , Ar ₁₈ , and Ar ₁₉ are the same or different Represents an arylene group, wherein X, k, j and n are the same as those in formula (I))

[0070]

Embedded image (Wherein, R ₂₁ is a substituted or unsubstituted aryl group, Ar
₂₀ , Ar ₂₁ , Ar ₂₂ and Ar ₂₃ represent the same or different arylene groups. X, k, j and n are the same as in the case of the general formula (I). )

[0071]

Embedded image (Wherein, R ₂₂ , R ₂₃ , R ₂₄ and R ₂₅ are a substituted or unsubstituted aryl group, Ar ₂₄ , Ar ₂₅ , Ar ₂₆ , Ar ₂₇ , Ar
₂₈ represents the same or different arylene group. X, k, j and n are the same as in the case of the general formula (I). )

[0072]

Embedded image(Where R₂₆, R₂₇Is a substituted or unsubstituted aryl
Group, Ar₂₉, Ar₃₀, Ar ₃₁Are the same or different allylenes
Represents a group. X, k, j and n are those in the case of general formula (I)
Is the same as )

Hereinafter, some specific examples of the polycarbonate containing the triarylamine structure in the main chain and / or the side chain are shown below, but the present invention is not limited to these specific examples.

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The polymer transporting substance having a triarylamine structure in the main chain and / or side chain is polymerized in the form of a homopolymer, a random copolymer, an alternating copolymer, or a block copolymer. . Since these polymer charge transport materials have a role as a binder resin, they need to have a film forming ability. Therefore, the molecular weight is
In the measurement by GPC, the molecular weight in terms of polystyrene M
10,000 to 500,000 is appropriate as w, and preferably 50,000 to 40,000.
It is ten thousand.

These polymer transport materials are disclosed in JP-A-8-269.
183, JP-A-9-71642, JP-A-9-71642
-104746, JP-A-9-272735, JP-A-11-29634, JP-A-9-235
367, JP-A-9-87376, JP-A-9-87376
JP-A-1110976, JP-A-9-268226, JP-A-9-221544, JP-A-9-227
No. 669, JP-A-9-157378, JP-A-9-302048, JP-A-9-32085, and JP-A-2000-26590.

In the photoreceptor of the present invention, a plasticizer or a leveling agent may be added to the charge transport layer 37.

As the plasticizer, those used as general plasticizers for general resins such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount of the plasticizer is preferably about 0 to 30% by weight based on the binder resin. It is.

As the leveling agent, silicone oils such as dimethyl silicone oil and methyl phenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used. , 0 to 1% by weight.

The coating method of the coating solution obtained as described above includes dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating and the like.
Conventional coating methods can be used. When the filler is contained on the photosensitive layer surface, the filler can be contained in the entire photosensitive layer.However, the filler concentration gradient is set so that the filler concentration is highest on the outermost surface side of the charge transport layer and lower on the support side. Alternatively, it is preferable that the charge transport layer be composed of a plurality of layers so that the filler concentration is gradually increased from the support side toward the surface side.

In the laminated electrophotographic photosensitive member of the present invention, it is preferable that a protective layer 39 is provided on the photosensitive layer for the purpose of protecting the photosensitive layer. The photoconductor shown in FIG. 2 and FIG.
Both the charge generation layer 35 and the charge transport layer 37 do not contain a filler, and the filler is included in the protective layer 39, so that the photoreceptor having no protective layer is distinguished from the photoreceptor. The above-described filler is used in the protective layer 39.

The material used for the protective layer 39 is AB
S resin, ACS resin, olefin-vinyl monomer copolymer, chlorinated polyether, aryl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyacrylate, polyallyl sulfone, polybutylene, polybutylene terephthalate, polycarbonate, polyether sulfone , Polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylbenthene, polypropylene, polyphenylene oxide, polysulfone, polystyrene, polyarylate, A
Resins such as S resin, butadiene-styrene copolymer, polyurethane, polyvinyl chloride, polyvinylidene chloride, and epoxy resin. From the viewpoints of filler dispersibility, residual potential, and coating film defects, polycarbonate or polyarylate is particularly effective and useful.

Examples of the solvent used for forming the protective layer 39 include tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, and acetone.
All solvents used in the charge transport layer 37 can be used. However, a solvent having high viscosity is preferable at the time of dispersion (at the time of preparing a coating solution for forming a protective layer), and a solvent having high volatility is preferable at the time of coating. When there is no solvent that satisfies these conditions, it is possible to use a mixture of two or more solvents having the respective physical properties, and may have a great effect on the dispersibility and residual potential of the filler. .

It is preferable that a charge transport material is added to the protective layer 39 in order to reduce residual potential, improve photosensitivity, and respond quickly. As the charge transport material to be added, the low-molecular charge transport material described in the description of the charge transport layer 35 is used. Further, the above-mentioned polymer charge transporting material is more preferably used in terms of improvement of abrasion resistance and high-speed response.

As a method for forming the protective layer, conventional methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, and ring coating can be used. Coats are more preferred. Furthermore, apply the required thickness of the protective layer at once,
Although it is possible to form a protective layer, it is more preferable to apply the coating two or more times to form a multilayer protective layer from the viewpoint of the uniformity of the filler in the film. By doing so, more effects can be obtained on the reduction of the residual potential, the improvement of the resolution, and the improvement of the wear resistance. The thickness of the protective layer is suitably about 0.1 to 10 μm.

Next, the case where the photosensitive layer has a single-layer structure 33 will be described. A photosensitive layer in which at least the above-described charge generating substance is dispersed in a binder resin can be used. The single-layer photosensitive layer can be formed by dissolving or dispersing the charge generating substance and the binder resin in an appropriate solvent, and applying and drying this. Further, the photosensitive layer may be of a function-separated type to which the above-mentioned charge transport material is added, and can be used favorably. If necessary, a plasticizer, a leveling agent, an antioxidant and the like can be added.

As the binder resin, in addition to using the binder resin described above for the charge transport layer 37 as it is, the charge generation layer 3
The binder resins described in 5 may be mixed and used. Of course, the above-mentioned polymer charge transport materials can also be used favorably. The amount of the charge generating substance is preferably 5 to 40 parts by weight, and the amount of the charge transporting substance is 0 to 1 part by weight based on 100 parts by weight of the binder resin.
It is preferably 90 parts by weight, more preferably 50 to 150 parts by weight.

The single-layer photosensitive layer comprises a charge-generating substance and a binder resin together with a charge-transporting substance if necessary, such as tetrahydrofuran,
A coating liquid dispersed by a disperser or the like using a solvent such as dioxane, dichloroethane, or cyclohexane can be used by a dip coating method, a spray coating method, a bead coating method, a nozzle coating method, a spinner coating method, a ring coating method, or the like.
The thickness of the single-layer photosensitive layer is suitably about 5 to 100 μm.

In a configuration in which the photosensitive layer 33 is the outermost layer, the photosensitive layer 33 contains a filler. In this case, all the fillers used in the charge transport layer or the protective layer 39 can be used. Although the filler can be contained in the entire photosensitive layer 33, a filler concentration gradient is provided or the photosensitive layer is composed of a plurality of layers, and the filler concentration is sequentially changed so that the surface contains a large amount of filler. That is an effective means. This photoreceptor is distinguished from the electrophotographic photoreceptor shown in FIG. 1 in which the photosensitive layer 33 does not contain a filler and a protective layer 39 containing a filler is formed. When the protective layer 39 is provided on the photosensitive layer 33, there may be a protective layer having the same configuration as described above.

In the photosensitive member of the present invention, an undercoat layer can be provided between the conductive support 31 and the photosensitive layer (not shown). The undercoat layer generally contains a resin as a main component. However, considering that the photosensitive layer is coated thereon with a solvent, these resins are resins having high solvent resistance to general organic solvents. desirable.

Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein and sodium polyacrylate, alcohol-soluble resins such as copolymerized nylon and methoxymethylated nylon, polyurethane, melamine resin, phenolic resin, alkyd-melamine. Curable resins that form a three-dimensional network structure, such as resins and epoxy resins, are exemplified.

The undercoat layer may be added with a fine powder pigment of a metal oxide exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide, etc. to prevent moire and reduce residual potential. Is also good.

These undercoat layers can be formed by using an appropriate solvent and a coating method as in the above-mentioned photosensitive layer. Furthermore, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used as the undercoat layer of the present invention. In addition, the undercoat layer of the present invention includes Al ₂
O ₃ provided by anodic oxidation, organic substances such as polyparaxylylene (parylene), SiO ₂ , SnO ₂ , Ti
Those provided with an inorganic substance such as O ₂ , ITO, CeO ₂ by a vacuum thin film forming method can also be used favorably. In addition, known materials can be used.

The thickness of the undercoat layer is suitably from 0 to 5 μm.

In the photoreceptor of the present invention, an intermediate layer can be provided between the photosensitive layer and the protective layer (not shown). The intermediate layer generally uses a binder resin as a main component. Examples of these resins include polyamide, alcohol-soluble nylon, water-soluble polyvinyl butyral, polyvinyl butyral, and polyvinyl alcohol. As a method for forming the intermediate layer, a normal coating method is employed as described above. The thickness of the intermediate layer is 0.05 to 2
About μm is appropriate.

In the present invention, antioxidants, plasticizers, lubricants, ultraviolet absorbers, low molecular weight compounds are added to each layer for the purpose of improving environmental resistance, especially for preventing a decrease in sensitivity and a rise in residual potential. Charge transport materials and leveling agents can be added. Representative materials of these compounds are described below.

Examples of the antioxidant that can be added to each layer include, but are not limited to, the following.

(A) Phenol compound 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, n-octadecyl-3- ( 4'-hydroxy-3 ', 5'-di-t-butylphenol),
2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'-methylene-bis- (4-
Ethyl-6-t-butylphenol), 4,4′-thiobis- (3-methyl-6-t-butylphenol),
4,4′-butylidenebis- (3-methyl-6-t-butylphenol), 1,1,3-tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane,
1,3,5-trimethyl-2,4,6-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ', 5'-di-
[t-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3'-bis (4'-hydroxy-3'-t-butylphenyl) butyric acid] crylic ester, tocopherols and the like.

(B) Paraphenylenediamines N-phenyl-N'-isopropyl-p-phenylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl- p-
Phenylenediamine, N, N'-di-isopropyl-p
-Phenylenediamine, N, N'-dimethyl-N, N '
-Di-t-butyl-p-phenylenediamine and the like.

(C) Hydroquinones 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t
-Octyl-5-methylhydroquinone, 2- (2-octadecenyl) -5-methylhydroquinone and the like.

(D) Organic sulfur compounds Dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate and the like.

(E) Organophosphorus compounds Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine and the like.

Examples of the plasticizer that can be added to each layer include, but are not limited to, the following.

(A) Phosphate ester plasticizer Triphenyl phosphate, tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, trichloroethyl phosphate, cresyl diphenyl phosphate, tributyl phosphate, tri-2 phosphate -Ethylhexyl, triphenyl phosphate and the like.

(B) Phthalate ester plasticizers Dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, diheptyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, di-n-phthalate Octyl, dinonyl phthalate, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, dicyclohexyl phthalate, butyl benzyl butyl, butyl lauryl phthalate, methyl oleyl phthalate, octyl decyl phthalate, dibutyl fumarate, Dioctyl fumarate and the like.

(C) Aromatic carboxylic acid ester plasticizers Trioctyl trimellitate, Tri-n trimellitate
-Octyl, octyl oxybenzoate and the like.

(D) Aliphatic dibasic ester plasticizers Dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, di-n-adipate
Octyl, n-octyl-n-octyl-n-decyl adipate, diisodecyl adipate, dicapryl adipate, di-2-ethylhexyl azelate, dimethyl sebacate,
Diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, di-2-ethylhexyl sebacate, di-2-ethoxyethyl sebacate, dioctyl succinate, diisodecyl succinate, dioctyl tetrahydrophthalate, dihydrotetrahydrophthalate -N-octyl and the like.

(E) Fatty acid ester derivatives butyl oleate, glycerin monooleate, methyl acetyl ricinoleate, pentaerythritol ester, dipentaerythritol hexaester,
Triacetin, tributyrin and the like.

(F) Oxyacid ester plasticizers Methyl acetyl ricinoleate, butyl acetyl ricinoleate, butyl phthalyl butyl glycolate, acetyl tributyl citrate and the like.

(G) Epoxy plasticizer Epoxidized soybean oil, epoxidized linseed oil, butyl epoxy stearate, decyl epoxy stearate, octyl epoxy stearate, benzyl epoxy stearate, dioctyl epoxy hexahydrophthalate, epoxy hexahydrophthalate Didecyl acid and the like.

(H) Dihydric alcohol ester plasticizers Diethylene glycol dibenzoate, triethylene glycol di-2-ethyl butyrate and the like.

(I) Chlorinated plasticizers Chlorinated paraffin, chlorinated diphenyl, chlorinated fatty acid methyl, methoxy chlorinated fatty acid methyl and the like.

(J) Polyester plasticizer Polypropylene adipate, polypropylene sebacate, polyester, acetylated polyester and the like.

(K) Sulfonic acid derivatives p-toluenesulfonamide, o-toluenesulfonamide, p-toluenesulfonethylamide, o-toluenesulfonethylamide, toluenesulfone-N-ethylamide, p-toluenesulfon-N-cyclohexyl Amides and the like.

(1) Citric acid derivatives Triethyl citrate, triethyl acetyl citrate, tributyl citrate, tributyl acetyl citrate, tri-2-ethylhexyl acetyl citrate, n-octyldecyl acetyl citrate and the like.

(M) Others terphenyl, partially hydrogenated terphenyl, camphor, 2
-Nitrodiphenyl, dinonylnaphthalene, methyl abietate and the like.

Examples of the lubricant that can be added to each layer include, but are not limited to, the following.

(A) Hydrocarbon compounds Liquid paraffin, paraffin wax, microwax, low-polymerized polyethylene and the like.

(B) Fatty acid compounds Lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid and the like.

(C) Fatty acid amide compound Stearyl amide, palmityl amide, olein amide, methylene bis-stearamide, ethylene bis-stearamide and the like.

(D) Ester compounds Lower alcohol esters of fatty acids, polyhydric alcohol esters of fatty acids, polyglycol esters of fatty acids and the like.

(E) Alcohol Compounds Cetyl alcohol, stearyl alcohol, ethylene glycol, polyethylene glycol, polyglycerol and the like.

(F) Metal soaps Lead stearate, cadmium stearate, barium stearate, calcium stearate, zinc stearate, magnesium stearate and the like.

(G) Natural waxes Carnauba wax, candelilla wax, beeswax, whale wax, Ibota wax, montan wax and the like.

(H) Others Silicone compounds, fluorine compounds and the like.

Examples of the ultraviolet absorber which can be added to each layer include the following, but are not limited thereto.

(A) Benzophenone 2-hydroxybenzophenone, 2,4-dihydroxybenzophenone, 2,2 ', 4-trihydroxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone, 2,2'- Dihydroxy 4-methoxybenzophenone and the like.

(B) Salicylate phenyl salicylate, 2,4-di-t-butylphenyl 3,5-di-t-butyl 4-hydroxybenzoate and the like.

(C) Benzotriazole type (2′-hydroxyphenyl) benzotriazole,
(2′-hydroxy 5′-methylphenyl) benzotriazole, (2′-hydroxy 5′-methylphenyl)
Benzotriazole, (2′-hydroxy 3′-tert-butyl 5′-methylphenyl) 5-chlorobenzotriazole

(D) Cyanoacrylate type Ethyl-2-cyano-3,3-diphenyl acrylate, methyl 2-carbomethoxy 3 (paramethoxy) acrylate and the like.

(E) Quencher (metal complex salt) Nickel (2,2′thiobis (4-t-octyl) phenolate) normal butylamine, nickel dibutyl dithiocarbamate, nickel dibutyl dithiocarbamate, cobalt dicyclohexyl dithiophosphate and the like.

(F) HALS (hindered amine) bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1 -[2- [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionyloxy] ethyl] -4- [3- (3,5-
Di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpyridine,
8-benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione, 4-benzoyloxy-2,
2,6,6-tetramethylpiperidine and the like.

Next, the electrophotographic method and the electrophotographic apparatus of the present invention will be described in detail with reference to the drawings.

FIG. 4 is a schematic diagram for explaining the electrophotographic apparatus of the present invention, and the following modified examples also belong to the category of the present invention. That is, in FIG. 4, the photoreceptor 1 has a photosensitive layer and an outermost layer containing a filler provided on a conductive support. The photoconductor 1 has a drum shape, but may have a sheet shape or an endless belt shape.

The charging roller 8, the pre-transfer charger 7, the transfer charger 10, the separation charger 11, and the pre-cleaning charger 13 include known devices such as a corotron, a scorotron, a solid charger (solid state charger), and a charging roller. Means are used. As the charging member, a member that is in contact with or close to the photoconductor is preferably used from the viewpoint of reducing ozone generation and power consumption. When the abrasion resistance of the photoreceptor is improved as in the present invention, accumulation of a low-resistance substance on the surface of the photoreceptor in repeated use may cause image blur. The generation of the low-resistance substance is mainly based on the reactive gas generated from the charging member, and it is very effective to use a charging member that is in contact with or disposed in proximity to the charging member.

Among them, in order to prevent the charging member from being contaminated, an appropriate gap is provided between the photosensitive member and the surface of the charging member.
The charging mechanism arranged close to the photoconductor is effectively used. At this time, the gap between the surface of the photoreceptor and the surface of the charging member is effectively 200 μm or less from the viewpoint of charging stability. More preferably, it is 100 μm or less. In addition, when charging the photosensitive member by the charging member, the photosensitive member is charged by an electric field in which a DC component and an AC component are superimposed on the charging member, thereby effectively reducing charging unevenness.

As the transfer means, generally, the above-mentioned charger can be used, but one using a transfer belt as shown in FIG. 4 can be effectively used.

The light sources such as the image exposure unit 10 and the neutralizing lamp 7 include a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, and a light emitting diode (LE).
D), semiconductor lasers (LD), electroluminescence (EL), and other general light-emitting materials can be used.
To irradiate only light in a desired wavelength range, various filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used.

The light source and the like are provided with a transfer step, a charge removal step, a cleaning step, and a pre-exposure step using light irradiation in addition to the steps shown in FIG.
Light is applied to the photoconductor.

The toner developed on the photosensitive member 1 by the developing unit 11 is transferred to the transfer paper 14, but not all of the toner is transferred, and toner remaining on the photosensitive member 1 is generated. Such toner is removed from the photoreceptor by the fur brush 18 and the cleaning brush 19. Cleaning may be performed only with a cleaning brush, and a known brush such as a fur brush or a mag fur brush is used as the cleaning brush.

When a positive (negative) charge is applied to the electrophotographic photosensitive member and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. If this is developed with toner of negative (positive) polarity (electrostatic detection fine particles), a positive image can be obtained, and if it is developed with toner of positive (negative) polarity, a negative image can be obtained. A known method is applied to such a developing unit.
In addition, a known method is used for the charge removing means.

FIG. 5 shows another example of the electrophotographic process according to the present invention. The photoreceptor 21 has at least a photosensitive layer, and further contains a filler in the outermost surface layer. The photoreceptor 21 is driven by drive rollers 22a and 22b, and is charged by a charger 23, image exposed by a light source 24, and developed (not shown). The transfer using the charger 25, the exposure before cleaning by the light source 26, the cleaning by the brush 27, and the charge removal by the light source 28 are repeatedly performed. In FIG. 5, the photoconductor 21
(Of course, in this case, the support is translucent), and light irradiation for pre-cleaning exposure is performed from the support side.

Further, although not shown, a member for supplying zinc stearate may be provided on the surface of the photoreceptor. By supplying zinc stearate on the surface of the photoreceptor, it is possible to suppress filming in a state where abrasion resistance is good, and further, in an electrophotographic process including the photoreceptor,
By repeatedly attaching toner to the photoreceptor and performing a toner collecting operation in the cleaning unit during non-image formation, the present invention is effective in suppressing image flow while maintaining abrasion resistance.
As a means for supplying the zinc stearate, it is very effective to include zinc stearate in a developer (toner) existing in the developing section.

If the amount of zinc stearate supplied to the photoreceptor is too large, the amount of output on the transferred output image also increases, which is not preferable because it causes a fixing failure. Further, when the friction coefficient of the surface of the photoreceptor is reduced to about 0.1 due to excessive supply of zinc stearate, the image density is lowered, which is not preferable. On the other hand, when the amount is small, filming of the toner component on the photoreceptor occurs, which leads to image deletion and non-uniformity of halftone, which is not preferable. For example, when zinc stearate is contained in the toner and supplied to the surface of the photoreceptor, the content is preferably 0.1 to 0.2% by weight in the toner.

Further, in the image forming process according to the present invention, it is possible to suppress the filming on the photosensitive and anti-photosensitive surface while maintaining the abrasion resistance by the toner adhesion to the photoreceptor and the toner collecting operation in the cleaning unit during non-image formation. Further, it is possible to suppress the adhesion and deposition of the product due to charging. This is considered to be due to a cleaning effect in which various kinds of deposits on the photosensitive member are discharged together with the toner. The toner adhesion and collection operation is performed by a toner adhesion amount of about halftone and an operation time of about 30 seconds (photosensitive member diameter 30 mm, linear velocity 12
(In the case of 5 mm / s), which is effective. A larger amount of adhesion and a longer operation time are not preferable in view of an increase in load on the cleaning unit and an increase in toner consumption. In the case where the photoconductor diameter and the linear velocity are different, it may be appropriately adjusted so that the same operating conditions as above are obtained.

The above-described electrophotographic process exemplifies an embodiment of the present invention, and other embodiments are of course possible. For example, in FIG. 5, the pre-cleaning exposure is performed from the support side, but this may be performed from the photosensitive layer side, or the image exposure and the erasing light irradiation may be performed from the support side. On the other hand, the light irradiation step includes image exposure,
Although the pre-cleaning exposure and the static elimination exposure are shown, the photosensitive member may be irradiated with light by providing other pre-transfer exposure, image exposure pre-exposure, and other known light irradiation steps.

The image forming means as described above may be fixedly incorporated in a copying machine, a facsimile, or a printer, or may be incorporated in the apparatus in the form of a process cartridge. The process cartridge includes a photoreceptor, and further includes a charging unit, an exposing unit, a developing unit, a transferring unit, a cleaning unit, and a discharging unit.
In the present invention, it is necessary to have at least a photoconductor and a developing unit containing the toner of the present invention. Although there are many shapes and the like of the process cartridge, a general example is shown in FIG.

[0147]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited by the examples. All parts are parts by weight. The measuring method used here is as follows.

1. GPC Here, the weight average molecular weight Mw and the number average molecular weight Mn
The value can be determined by various methods.
Although there are some differences due to differences, in the present invention,
Defined as determined according to the following measurement method. Sand
And gel permeation chromatography (G
PC) under the conditions described below under the weight average molecular weight Mw
And the number average molecular weight Mn. Smell at 40 ° C
The solvent (tetrahydrofuran) at a flow rate of 1.2 ml / min.
Flow quickly, tetrahydrofuran with a concentration of 15ml / 5ml
Inject 3 mg of the sample solution as a sample weight and measure.
When measuring the molecular weight of a sample, the molecular weight of the sample
Volumes made with several monodisperse polystyrene standards
Range where the logarithm of molecular weight and count number of the calibration curve
Select the measurement conditions contained in. Note that the measurement results
Reliability was measured using NBS706 police under the above measurement conditions.
The weight average molecular weight Mw = 28.8 × 10^Four  Number average molecular weight Mn = 13.7 × 10^Four  Can be confirmed. Also use
A GPC column that satisfies the above conditions
Any column may be used if desired. Specifically
Is, for example, TSK-GEL, GMH6 (manufactured by Toyo Soda Co., Ltd.)
Etc. can be used. The solvent and measurement temperature are
The conditions are not limited to those described, but may be changed to appropriate conditions.
May be changed.

[0149] 2. Measurement of carrier particle size distribution 1) 100 g of the collected sample is weighed after mixing well. 2) The weighed sample is placed in the uppermost sieve on which the sieves for measuring the particle size distribution are stacked, and is placed in a low tap sieve shaker. (The operation time of the sieve shaker is 6 minutes or more, and the standard is 8 minutes.) 3) After stopping the low tap sieve shaker, collect the samples on each sieve with a paintbrush and use the upper balance to measure the upper sample. Weigh sequentially to the nearest 0.1 g. 4) Round the result obtained to the first decimal place by weight percentage.

[0150] 3. Magnetic property measurement procedure 1) Automatic recording device for DC magnetization characteristics Type 3257-36 manufactured by Yokogawa Hokushin Electric Co., Ltd. 2) Electromagnet type magnet Type 3261-15 manufactured by Yokogawa Hokushin Electric Co., Ltd. 3) Pickup coil (Bi & H coil) Yokogawa Hokushin Electric Co., Ltd. Type 3261-20 4) Material cell (made of acrylic resin) 5) Electronic balance Minimum scale 1mg

(Preparation of Toner A) Polyester resin (A) 60 parts Polyester resin (B) 40 parts Hydrogenated petroleum resin (hydrogenation rate 90%, composition: dicyclopentadiene + aromatic hydrocarbon) 15 parts Carnauba wax (Melting point: 82 ° C., acid value: 2) 3 parts Carbon black (# 44: manufactured by Mitsubishi Kasei) 8 parts Chromium-containing monoazo complex 3 parts About 3 at a temperature of ℃
After heating and melting for 0 minutes and cooling to room temperature, the obtained kneaded material was pulverized and classified by a jet mill to obtain a toner having a volume average particle diameter of 8.0 μm. The number average molecular weight (M
n) was 2,600, and the ratio of molecules having a molecular weight of 1,000 or less was 43% by number. Further, 1.2 parts of an additive (R972 manufactured by Nippon Aerosil Co., Ltd.) was added to 100 parts of the toner, and the mixture was stirred and mixed with a Henschel mixer. The polyesters (A) and (B) are as shown in Table 1 below.

[0152]

[Table 1]

(Preparation of Toner B) Toner B was obtained in the same manner except that the amount of the additive in toner A was changed to 0.5 part.

(Preparation of carrier) Core material F-300 5000 parts Dimethyl silicone resin 90 parts γ- (2-aminoethyl) aminopropyltrimethoxysilane 9 parts Conductive carbon black 11 parts Toluene 810 parts Rotary type in fluidized bed The coating liquid was applied onto the above-mentioned carrier core material by using a coating apparatus in which the bottom plate disk was rotated at a high speed to perform a coating while forming a swirling flow. The obtained carrier was heated in an electric furnace at a temperature of 300 ° C. for 1 hour to obtain a carrier. The carrier core material F
-300 is shown in Table 2 below.

[Table 2]

(Preparation of Developer) 4.0 parts of the toner and 96.0 parts of the carrier were mixed and stirred with a Turbuler T2C type to obtain a two-component developer.

[Preparation of Photoreceptor a] An undercoat layer coating solution, a charge generation layer coating solution having the following composition
And a coating liquid for the charge transport layer are sequentially applied and dried, and then 3.5.
An electrophotographic photoreceptor comprising a μm undercoat layer, a 0.2 μm charge generation layer, a 22 μm charge transport layer, and a 2 μm protective layer was formed.

(Undercoat layer coating solution) Titanium dioxide powder 400 parts Melamine resin 65 parts Alkyd resin 120 parts 2-butanone 400 parts

(Coating Solution for Charge Generating Layer) 8 parts of a bisazo pigment having the following structure

Embedded image 6 parts of trisazo pigment having the following composition

Embedded image Polyvinyl butyral 5 parts 2-butanone 200 parts Cyclohexanone 400 parts

(Coating solution for charge transport layer) A type polycarbonate 10 parts Charge transport material of the following structural formula 7 parts

Embedded image Tetrahydrofuran 400 parts Cyclohexanone 150 parts

(Protective Layer Coating Solution) A-Type Polycarbonate 10 parts Charge transport material of the following structural formula 8 parts

Embedded image Tetrafluoroethylene particles 4 parts Tetrahydrofuran 400 parts Cyclohexanone 150 parts

[Preparation of Photoconductor b] Photoconductor b was obtained in the same manner except that alumina fine particles were used in place of tetrafluoroethylene particles in the coating liquid for the protective layer in photoconductor a.

[Preparation of Photoconductor c] Photoconductor c was obtained in the same manner except that the coating liquid for the protective layer in photoconductor a was changed to the following.

(Protective Layer Coating Solution) 18 parts of a polymer charge transport material having the following structural formula

Embedded image Tetrafluoroethylene particles 4 parts Tetrahydrofuran 400 parts Cyclohexanone 150 parts

[Preparation of Photoconductor d] Photoconductor d was obtained in the same manner as in photoconductor a except that tetrafluoroethylene particles in the coating solution for the protective layer in photoconductor a were not used.

(Example 1) A two-component developer using the toner A was set in a developing section of an image MF4570 manufactured by Ricoh Company. The photoconductor a is incorporated in the image MF4570. Durability test 2 with the above combination
The evaluation was performed up to 00k sheets, and the image evaluation and the wear amount of the photoreceptor were measured. Table 3 shows the results. In addition, the above-mentioned imagi
o MF4570 is set so that the fixing temperature is controlled to be lower by 10 to 20 ° C. than the conventional one in correspondence with the low-temperature fixing toner.

(Example 2) A two-component developer using the toner A was set in a developing section of an image MF4570 manufactured by Ricoh Company. A photoconductor b is incorporated in the image MF4570. Durability test 2 with the above combination
The evaluation was performed up to 00k sheets, and the image evaluation and the wear amount of the photoconductor were measured. Table 3 shows the results.

(Example 3) A two-component developer using the toner A was set in a developing section of an image MF4570 manufactured by Ricoh Company. The photoconductor c is incorporated in the image MF4570. Durability test 2 with the above combination
The evaluation was performed up to 00k sheets, and the image evaluation and the wear amount of the photoconductor were measured. Table 3 shows the results.

(Comparative Example 1) A two-component developer using the toner B was set in a developing section of an image MF4570 manufactured by Ricoh Company. The photoconductor a is incorporated in the image MF4570. When the image evaluation was performed with the above combination, the image density was low and the image was extremely poorly resolved. Next, an attempt was made to conduct a durability test. However, when 1 k sheets were passed, a large amount of toner filmed on the surface of the photoreceptor and could not be continued.

(Comparative Example 2) A two-component developer using the toner A was set in a developing section of an image MF4570 manufactured by Ricoh Company. The image bearing member d is incorporated in the image MF4570. Durability test 2 with the above combination
The evaluation was performed up to 00k sheets, and the image evaluation and the wear amount of the photoconductor were measured. Table 3 shows the results.

[0170]

[Table 3]

From a comparison between Example 1 and Comparative Example 1, it can be confirmed that in a toner containing a large amount of low molecular weight components, if a large amount of inorganic fine particles are added to the toner, the toner itself will film on the photosensitive member. . Example 1 and Comparative Example 2
From the comparison with the above, it can be seen that the amount of abrasion of the photoreceptor is reduced by including the filler in the outermost layer of the photoreceptor, and the effect of stabilizing the image quality accompanying the reduction. From the comparison of Examples 1, 2 and 3, the effect of further reducing the abrasion amount of the photoconductor and improving the image quality by using a metal oxide for the filler and a polymer-based charge transport material for the photoconductor. Can be confirmed.

Example 4 A photoreceptor was prepared in the same manner as in Example 2 except that the coating solution for the charge generation layer of the photoreceptor used in Example 2 was changed to the following, and a durability test was performed. Was done. (Coating liquid for charge generation layer) 8 parts of bisazo pigment having the following structure

Embedded image 6 parts of trisazo pigment having the following structure

Embedded image Polyvinyl butyral 5 parts 2-butanone 200 parts Cyclohexanone 400 parts

Example 5 A photoconductor was prepared in the same manner as in Example 2 except that the charge generation coating solution for the photoconductor used in Example 2 was changed to the following, and a durability test was performed. went. (Charge generation layer coating liquid) Titanyl phthalocyanine having the following XD spectrum shown in FIG. 7 8 parts Polyvinyl butyral 5 parts 2-butanone 400 parts

Example 6 A durability test was performed in the same manner as in Example 2 except that the imager MF4570 manufactured by Ricoh Company used in Example 2 was modified, and the charging member was changed from a contact charging roller to a scorotron charger. The surface potential of the unexposed photosensitive member is the same as that of the second embodiment (−900).
V), the applied voltage and the grid voltage were adjusted.

(Example 7) The imager MF4570 manufactured by Ricoh Company used in Example 2 was modified, and a thickness of 250 μm was applied to both ends (non-image area) of a charging roller as a charging member.
A Teflon tape was wound around the photosensitive member and the gap between the surface of the photosensitive member and the surface of the charging member was set to be 250 μm, and a durability test was performed in the same manner as in Example 2. The charging was performed in Example 2.
Similarly to the above, only the DC component was used, and the applied voltage was adjusted so that the surface potential of the unexposed portion of the photoconductor was the same as in Example 2 (-900 V).

(Embodiment 8) According to the embodiment 7, the thickness
A 0 μm Teflon tape was wrapped, and the gap between the surface of the photoreceptor and the surface of the charging member was set to 100 μm. A durability test was performed in the same manner as in Example 2. In addition, the charging is performed only with the DC component similarly to the second embodiment, and the surface potential of the unexposed portion of the photoconductor is the same as that of the second embodiment (−900 V).
The applied voltage was adjusted.

Example 9 A durability test was performed in the same manner as in Example 7, except that the charging conditions in Example 7 were changed as follows. Charging conditions: DC bias: -900V AC bias: 1.8kV (peak to peak), frequency 2k
Hz

The results of the durability tests of Examples 4 to 9 are shown in Table 4 in comparison with the results of Example 2.

[Table 4]

From the comparison with Example 2, when a specific charge generating substance is contained (Examples 4 and 5), the photosensitivity of the photoreceptor increases, and a predetermined exposed portion potential in the actual machine is obtained. The amount of light for writing was reduced. as a result,
The fatness was suppressed and an image with high resolution was obtained. When the charger was used (Example 6), the smell of ozone was strong, and the image after the run was slightly blurred in the image. Thus, the effect of the contact member appears (Example 2). When the proximity charging member was used (Examples 7 and 8), the contamination of the charging member was extremely small as compared with Example 2. When the gap between the charging member and the photoreceptor was too large, it was recognized that charging stability was slightly lacking. However, when the AC is superimposed (Example 9), this charging unevenness is not recognized at all, and the effect of the AC superposition appears.

(Example 10) Under the same conditions as in Example 3, a durability test of 100 k sheets was further added, and a durability test of a total of 300 k sheets was performed.

(Example 11) In Example 10, imagio MF4570 manufactured by Ricoh Co., Ltd. was modified, and a zinc stearate supply member was provided between the cleaning member and the charging member. Mechanism for 10 seconds). Under these conditions, a durability test was performed in the same manner as in Example 10.

Example 12 A durability test was performed in the same manner as in Example 10, except that 0.15% of powdery zinc stearate was added to the toner supplied to the developing unit.

(Embodiment 13)
Example 1 except that for each pass of the 00 sheets, as a non-image forming operation, only exposure up to the light portion potential, toner development by the developing unit and toner collecting operation on the photosensitive member surface by the cleaning unit were repeated for 20 seconds. A durability test was performed in the same manner as in No. 12.

The results of the durability tests of Examples 10 to 13 are shown in Table 5.

[Table 5]

Under the conditions of Example 10, when the durability test was performed up to 300k sheets, slight filming occurred on the surface of the photoreceptor, and the resulting image omission occurred (however, not a problematic level). . In contrast, Example 11,
By supplying zinc stearate to the surface of the photoreceptor as in 12, filming could be prevented. Further, by performing the photoconductor surface cleaning operation as in Example 13, the image blur could be completely eliminated even under high temperature and high humidity (30 ° C. 90% RH).

[0186]

According to the present invention, the number average molecular weight (Mn) of the binder resin for toner base particles is 3000 or less,
A material having 40% by number or more of molecules having a molecular weight of 1000 or less and an external addition amount of inorganic fine particles of 1.0% by weight or more, and a latent image carrier containing a filler in the outermost layer as a latent image carrier By using the image forming method / apparatus used, film shaving of the latent image bearing member is small, and a stable image density can be obtained even in repeated use.

[Brief description of the drawings]

FIG. 1 is a diagram showing a layer configuration of an electrophotographic photosensitive member used in the present invention.

FIG. 2 is a diagram showing a layer configuration of another electrophotographic photosensitive member used in the present invention.

FIG. 3 is a diagram showing a layer configuration of another electrophotographic photosensitive member used in the present invention.

FIG. 4 is a diagram illustrating an electrophotographic process and an electrophotographic apparatus according to the present invention.

FIG. 5 is a view for explaining another electrophotographic process and an electrophotographic apparatus of the present invention.

FIG. 6 is a view for explaining a process cartridge for an electrophotographic apparatus.

FIG. 7: X of titanyl phthalocyanine used in Example 7
The figure showing the D spectrum.

[Explanation of symbols]

 31 conductive support 33 single-layer photosensitive layer 35 charge generation layer 37 charge transport layer 39 protective layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) G03G 5/07 G03G 5/07 5/147 503 5/147 503 504 504 504 15/02 101 15/02 101 21 / 00 21/00 (72) Inventor Ken Mochizuki 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Shinichiro Yagi 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Company (72) Inventor Tomomi Tamura 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Tatsuya 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (Reference) 2H005 AA08 CA25 CB13 DA07 EA06 EA07 2H068 AA04 AA19 BA39 BA47 BB31 BB44 CA33 FB07 FB08 FC01 FC05 FC15 2H134 GA01 GB02 HB00 JB00 KC03 KG03 KH01 LA00 2H200 FA09 GA16 GA17 GA23 HA0 1 HA02 HA11 HA28 HB12 HB21 HB48 LA07 LA14 NA06

Claims (27)

[Claims] An image forming method for forming an image on a transfer material through at least charging, exposing, developing and transferring steps, and a toner used in the developing step in an image forming apparatus, wherein the toner has a number average molecular weight ( Mn) is 3000 or less, the number distribution of molecules having a molecular weight of 1000 or less is 40% or more, and 1.0% by weight or more of inorganic fine particles are externally added to the toner base particles. Development toner. 2. A method for forming an image on a transfer material through at least charging, exposing, developing and transferring steps, wherein the toner used in the developing step has a number average molecular weight (Mn) of 3000 or less and a number distribution The latent image carrier used in an image forming method and an image forming apparatus is a toner in which the above-mentioned toner has a molecular weight of 1000 or less, and 40% or more of the molecules and inorganic fine particles are added to the toner base particles in an amount of 1.0% by weight or more. A latent image carrier, wherein the outermost layer of the latent image carrier contains a filler. 3. The electrophotographic photoreceptor according to claim 2, wherein said latent image carrier is formed by forming a photosensitive layer and a protective layer on a conductive substrate, and said protective layer contains a filler. The latent image carrier as described in the above. 4. The latent image carrier according to claim 2, wherein the filler is a metal oxide. 5. The latent image carrier according to claim 3, wherein the protective layer contains a charge transport material. 6. The latent image carrier according to claim 5, wherein the charge transport material is a polymer charge transport material. 7. A charge generating substance contained in the latent image carrier has a diffraction peak (± 0.2 °) at a Bragg angle 2θ with respect to CuKα characteristic X-ray (wavelength 1.514 °).
7. A titanyl phthalocyanine having a maximum diffraction peak at least at 27.2 °.
The latent image carrier according to any one of the above. 8. The latent image carrier according to claim 2, wherein the charge generation material contained in the latent image carrier is an azo pigment represented by the following structural formula (A). Image carrier. Embedded image (In the formula, Cp ₁ and Cp ₂ represent a coupler residue represented by the following formula (B) and may be the same or different.
₂₀₁ and R ₂₀₂ each represent any of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, and a cyano group, and may be the same or different. ) (Wherein, R ₂₀₃ represents a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group.
₂₀₄ , R ₂₀₅ , R ₂₀₆ , R ₂₀₇ , and R ₂₀₈ each represent a hydrogen atom, a nitro group, a cyano group, a halogen atom such as fluorine, chlorine, bromine, or iodine, or an alkyl group such as a trifluoromethyl group, a methyl group, or an ethyl group. Represents an alkoxy group such as a methoxy group or an ethoxy group, a dialkylamino group, or a hydroxyl group, and Z represents a group of atoms necessary to form a substituted or unsubstituted aromatic carbocyclic ring or a substituted or unsubstituted aromatic heterocyclic ring. Represents) 9. An image forming method comprising forming an image on a transfer material through at least a charging step, an exposing step, a developing step, and a transferring step, wherein the toner used in the developing step has a number average molecular weight (Mn) of 3,000. In the following, the number distribution of molecules having a molecular weight of 1,000 or less is 40% or more in the number distribution, the toner base particles are externally added with inorganic fine particles in an amount of 1.0% by weight or more, and the latent image carrier used is the outermost layer. An image forming method characterized by comprising a filler. 10. The electrophotographic photoconductor according to claim 9, wherein the latent image carrier is formed by forming a photosensitive layer and a protective layer on a conductive substrate, and the protective layer contains a filler. The image forming method as described in the above. 11. The image forming method according to claim 9, wherein the filler is a metal oxide. 12. The image forming method according to claim 10, wherein the protective layer contains a charge transport material. 13. An image forming method according to claim 12, wherein said charge transport material is a polymer charge transport material. 14. An image forming apparatus which forms an image on a transfer material through at least a charging unit, an exposing unit, a developing unit, and a transferring unit, wherein the number average molecular weight (Mn) of the toner used in the developing step is 3000. Below, on the number distribution, molecules having a molecular weight of 1000 or less are 40% or more,
An image forming apparatus comprising: a toner in which inorganic fine particles are externally added to the toner base particles in an amount of 1.0% by weight or more; and a latent image carrier to be used contains a filler in an outermost layer. 15. An electrophotographic photosensitive member comprising a photosensitive layer and a protective layer formed on a conductive substrate, wherein the protective layer contains a filler. The image forming apparatus as described in the above. 16. The image forming apparatus according to claim 14, wherein the filler is a metal oxide. 17. The image forming apparatus according to claim 15, wherein the protective layer contains a charge transport material. 18. The image forming apparatus according to claim 17, wherein the charge transport material is a polymer charge transport material. 19. The charge generation substance contained in the latent image carrier has a diffraction peak (± 0.2 °) at a Bragg angle 2θ of at least 27.2 with respect to CuKα characteristic X-ray (wavelength 1.514 °). 2. A titanyl phthalocyanine having a maximum diffraction peak at ゜.
An image forming apparatus according to any one of claims 4 to 18. 20. The image according to claim 14, wherein the charge generating substance contained in the latent image carrier is an azo pigment represented by the following structural formula (A). Forming equipment. Embedded image (In the formula, Cp ₁ and Cp ₂ represent a coupler residue represented by the following formula (B) and may be the same or different.
₂₀₁ and R ₂₀₂ each represent any of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, and a cyano group, and may be the same or different. ) (Wherein, R ₂₀₃ represents a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or an aryl group such as a phenyl group.
₂₀₄ , R ₂₀₅ , R ₂₀₆ , R ₂₀₇ , and R ₂₀₈ each represent a hydrogen atom, a nitro group, a cyano group, a halogen atom such as fluorine, chlorine, bromine, or iodine, or an alkyl group such as a trifluoromethyl group, a methyl group, or an ethyl group. Represents an alkoxy group such as a methoxy group or an ethoxy group, a dialkylamino group, or a hydroxyl group, and Z represents a group of atoms necessary to form a substituted or unsubstituted aromatic carbocyclic ring or a substituted or unsubstituted aromatic heterocyclic ring. Represents) 21. An image exposure device comprising: an LD or an LE.
21. An image forming apparatus according to claim 14, wherein the apparatus is a so-called digital type electrophotographic apparatus in which an electrostatic latent image is written on a latent image carrier by using D or the like. apparatus. 22. An image forming apparatus according to claim 14, wherein said charging means has a charging member in contact with or close to the latent image carrier. 23. The image forming apparatus according to claim 22, wherein a gap between the charging member and the latent image carrier is 200 μm or less. 24. The image forming apparatus according to claim 22, wherein an alternating current component is superimposed on a direct current component on the charging member to charge the latent image carrier. 25. The image forming apparatus according to claim 14, wherein zinc stearate is supplied and applied to the surface of the latent image carrier. 26. The image forming apparatus according to claim 14, wherein the toner used in said developing means contains powdered zinc stearate. 27. A method for cleaning a surface of an image carrier by repeating a step of attaching toner to a surface of an image carrier from a developing unit and a step of collecting toner on the image carrier by a cleaning unit during non-image formation. The image forming apparatus according to any one of claims 14 to 26.