JP6337553B2 - Electrophotographic photosensitive member, electrophotographic photosensitive member cartridge, and image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member, an electrophotographic photosensitive member cartridge, and an image forming apparatus. In particular, the present invention relates to an electrophotographic photosensitive member, an electrophotographic photosensitive member cartridge, and an image forming apparatus that are remarkably excellent in adhesiveness of a photosensitive layer.

The electrophotographic technology is widely used as a copying machine, a printer, and a printing machine because a high-quality image can be obtained immediately. For the electrophotographic photoreceptor (hereinafter referred to as “photoreceptor” as appropriate) which is the core of the electrophotographic technology, an organic photoconductive material having advantages such as non-polluting, easy film formation and easy production was used. Photoconductors are widely used.
In recent years, due to the demand for higher image quality, the diameter of toner has been reduced, and in particular, the shape of a chemical toner is often close to a sphere, so that when the toner remaining on the photoreceptor is cleaned with a blade, the toner slips through. This is likely to occur, and as a result, there is a high possibility of image defects such as dirt. For this reason, measures are often taken to prevent the toner from slipping through contact of the cleaning blade with the photosensitive member with a strong pressure.

  If the contact pressure of the cleaning blade to the photoconductor increases, the blade will repeatedly stick to / slide with the surface of the photoconductor, causing chatter due to the so-called stick-slip phenomenon, resulting in the risk of poor cleaning and abnormal noise. Becomes higher. Further, by rotating the external additive or toner carrier, which is a toner component, strongly pressed against the photoconductor via the nip portion through the cleaning blade, a reduction in the life of the photoconductor due to an increase in wear of the photosensitive layer, Image defects due to circumferential scratches are also likely to occur. In addition, toner additives such as external additives and wax adhere to the surface of the photoconductor, making it difficult to remove, so that a so-called filming phenomenon is likely to occur, and the risk of persistent image defects increases. .

  Thus, the photoreceptor is required to have surface mechanical properties that minimize image defects, abnormal noise, and lifetime reduction even under more severe use conditions. Although it has been studied to provide a protective layer on the outermost layer of the photoreceptor as a means to improve the surface mechanical properties, the productivity decreases and the cost increases. There are many difficult cases. On the other hand, the use of a polyester resin, especially a polyarylate resin (fully aromatic polyester resin) having a high elastic deformation rate as the outermost layer of the photoreceptor is a means to meet the above-mentioned demands for improving mechanical properties. It has been put into practical use.

  For example, an electrophotographic photoreceptor using a polyarylate resin marketed under the trade name “U-polymer” as a binder has been reported to have improved sensitivity as compared to the case of using polycarbonate (Patent Document 1). reference). However, the coating solution prepared by dissolving this resin is low in stability, and coating production may be difficult. To solve this problem, a polyester resin using a divalent phenol component having a specific structure is used as a binder resin, so that the stability of a coating solution used for producing an electrophotographic photoreceptor is improved, and the electrophotographic photoreceptor machine is used. Improvement of mechanical strength and wear resistance has been reported (see Patent Documents 2 to 4). Furthermore, it has been reported that the mechanical strength of the photoreceptor is further improved by using a diphenyl ether dicarboxylic acid component as the dicarboxylic acid component of the polyester resin (see Patent Document 5 and Patent Document 6). However, the polyarylate resin has a problem that the molecular polarity is large and the charge transport ability is relatively inferior to that of the polycarbonate resin.

On the other hand, in resins such as polyolefins, it is generally known that the adhesion is improved by introducing carboxyl groups (Patent Document 7). However, the use of a resin having many polar groups in the photosensitive layer is an electrophotographic photoreceptor. Therefore, it has been required to reduce polar groups as much as possible (Patent Document 8).

JP-A-56-135844 Japanese Patent Laid-Open No. 3-6567 JP-A-9-22126 JP 2004-294750 A JP 2006-53549 A JP 2008-293006 A JP-A-7-206946 Japanese Patent No. 36221169

According to the studies by the inventors, when the polyarylate resin is contained in the photosensitive layer, the wear resistance is improved, but since the shrinkage of the photosensitive layer is increased, the internal stress is increased and the adhesion of the photosensitive layer is sufficient. However, there is a problem that peeling of the layer occurs when the adhesion to the substrate or the adjacent layer is insufficient.
The present invention has been made in view of the above problems. That is, an object of the present invention is to provide an electrophotographic photosensitive member in which the adhesion of the photosensitive layer is remarkably maintained without affecting the characteristics of the photosensitive member and the electric characteristics are good. To provide a process cartridge and an image forming apparatus used.

The present inventors have found that the adhesiveness can be remarkably improved by an electrophotographic photosensitive member containing a resin having a specific amount of terminal carboxylic acid in the photosensitive layer. That is, the gist of the present invention is as follows.
<1> An electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, wherein the photosensitive layer has a carboxylic acid terminal value of 100 μeq / g or more and 500 μeq / g or less and triphenylamine The polyarylate resin containing a compound is represented by the following formula (1):
An electrophotographic photosensitive member, characterized by chromatic structural units.

(In formula (1), Ar ^{1 to} Ar ⁴ each independently represents an arylene group which may have a substituent, X represents a single bond, an oxygen atom, a sulfur atom, or an alkylene group. S represents 0. And represents an integer of 2 or less, and Y represents a single bond, an oxygen atom, a sulfur atom, or an alkylene group.
<2> The terminal value of the carboxylic acid is 150 μeq / g or more and 500 μeq / g or less.
<2> The electrophotographic photosensitive member according to <1>.
< 3 > The electrophotographic photosensitive member according to <1> or <2> , wherein the polyarylate resin has a viscosity average molecular weight Mv of 10,000 to 200,000.
< 4 > A process cartridge comprising the electrophotographic photosensitive member according to any one of <1> to < 3 >, and a charging unit that charges the electrophotographic photosensitive member.
< 5 > The electrophotographic photosensitive member according to any one of <1> to < 3 >, a charging unit that charges the electrophotographic photosensitive member, and an electrostatic that performs exposure on the charged electrophotographic photosensitive member. An image forming apparatus comprising: an exposure unit that forms a latent image; a developing unit that develops the electrostatic latent image with toner; and a transfer unit that transfers the toner to a transfer target.

  The electrophotographic photosensitive member of the present invention can significantly improve the adhesion of the photosensitive layer by containing a resin having a specific amount of terminal carboxylic acid in the charge transporting layer. It is possible to provide a photographic process cartridge and an image forming apparatus including the electrophotographic photosensitive member.

1 is a schematic diagram illustrating a main configuration of an embodiment of an image forming apparatus of the present invention. The powder X-ray-diffraction spectrum by CuK (alpha) characteristic X-ray of the oxytitanium phthalocyanine used in the Example is shown.

  Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention is not limited to the following descriptions, and can be appropriately modified and implemented without departing from the gist of the present invention.

[Electrophotographic photoreceptor]
Hereinafter, the electrophotographic photoreceptor of the present invention will be described in detail.
<Conductive support>
As the conductive support used for the photoreceptor, for example, metal materials such as aluminum, aluminum alloy, stainless steel, copper, and nickel, and conductive powders such as metal, carbon, and tin oxide are added to impart conductivity. A resin material, a resin, glass, paper, or the like on which a conductive material such as aluminum, nickel, or ITO (indium tin oxide) is deposited or applied on the surface is mainly used. As a form, a drum shape, a sheet shape, a belt shape or the like is used. For conductive support of metallic materials, for control of conductivity and surface properties, and for defect coating. A conductive material having an appropriate resistance value may be applied.

When a metal material such as an aluminum alloy is used as the conductive support, it may be used after an anodized film is applied. When an anodized film is applied, it is desirable to perform a sealing treatment by a known method.
For example, it is formed by anodizing in an acidic bath of chromic acid, sulfuric acid, oxalic acid, boric acid, sulfamic acid, etc., but anodizing in sulfuric acid gives better results. In the case of anodic oxidation in sulfuric acid, the sulfuric acid concentration is 100-300 g / l, the dissolved aluminum concentration is 2-15 g / l, the liquid temperature is 15-30 ° C., the electrolysis voltage is 10-20 V, and the current density is 0.5-. it is preferably in the range of 2A / dm ^2, but not limited to the above conditions.
It is preferable to perform a sealing treatment on the anodic oxide film thus formed. The sealing treatment may be performed by a normal method. For example, the low-temperature sealing treatment is performed by immersion in an aqueous solution containing nickel fluoride as a main component, or the high-temperature sealing is performed by immersion in an aqueous solution containing nickel acetate as a main component. It is preferable that the treatment is performed.

The concentration of the nickel fluoride aqueous solution used in the case of the low-temperature sealing treatment can be appropriately selected, but more preferable results are obtained when it is used in the range of 3-6 g / l. Further, in order to proceed the sealing treatment smoothly, the treatment temperature is 25-40 ° C., preferably 30-35 ° C., and the pH of the nickel fluoride aqueous solution is 4.5-6.5, preferably It is better to process in the range of 5.5-6.0. As the pH adjuster, oxalic acid, boric acid, formic acid, acetic acid, sodium hydroxide, sodium acetate, aqueous ammonia and the like can be used. The treatment time is preferably in the range of 1 to 3 minutes per 1 μm of film thickness. In order to further improve the physical properties of the film, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant or the like may be added to the nickel fluoride aqueous solution. Subsequently, it is washed with water and dried to finish the low temperature sealing treatment.

  As the sealing agent in the case of the high temperature sealing treatment, an aqueous solution of a metal salt such as nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, barium nitrate can be used, and it is particularly preferable to use nickel acetate. . The concentration in the case of using an aqueous nickel acetate solution is preferably in the range of 5-20 g / l. The treatment temperature is 80-100 ° C., preferably 90-98 ° C., and the pH of the nickel acetate aqueous solution is preferably 5.0-6.0. Here, ammonia water, sodium acetate, or the like can be used as the pH adjuster. The treatment time is 10 minutes or longer, preferably 20 minutes or longer. In this case as well, sodium acetate, organic carboxylic acid, anionic and nonionic surfactants may be added to the nickel acetate aqueous solution in order to improve the film properties.

  Subsequently, it is washed with water and dried to finish the high temperature sealing treatment. When the average film thickness is thick, stronger sealing conditions are required due to the higher concentration of the sealing liquid and high temperature / long-time treatment. Accordingly, productivity is deteriorated and surface defects such as spots, dirt, and dusting are likely to occur on the coating surface. From such a point, it is preferable that the average thickness of the anodic oxide coating is usually 20 μm or less, particularly 7 μm or less.

  The support surface may be smooth, or may be roughened by using a special cutting method or polishing. Further, it may be roughened by mixing particles having an appropriate particle diameter with the material constituting the support. In order to reduce the cost, it is possible to use the drawing tube as it is without cutting. In particular, when using a non-cutting aluminum substrate such as drawing, impact processing, ironing, etc., it is preferable because the treatment eliminates dirt, foreign matter, and other foreign matters, small scratches, etc., and a uniform and clean substrate can be obtained. .

<Underlayer>
An undercoat layer may be provided between the conductive support and the photosensitive layer described later for improving adhesion and blocking properties. As the undercoat layer, a resin, a resin in which particles such as a metal oxide are dispersed, or the like is used.
Examples of the metal oxide particles used for the undercoat layer include metal oxide particles containing one metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, iron oxide, calcium titanate, Examples thereof include metal oxide particles containing a plurality of metal elements such as strontium titanate and barium titanate. Only one type of particles may be used, or a plurality of types of particles may be mixed and used. Among these metal particles, titanium oxide and aluminum oxide are preferable, and titanium oxide is particularly preferable. The surface of the titanium oxide particles may be treated with an inorganic substance such as tin oxide, aluminum oxide, antimony oxide, zirconium oxide, or silicon oxide, or an organic substance such as stearic acid, polyol, or silicone. As the crystal form of the titanium oxide particles, any of rutile, anatase, brookite, and amorphous can be used. Moreover, the thing of a several crystal state may contain.

Various particle diameters of the metal oxide particles can be used. Among these, from the viewpoint of characteristics and liquid stability, the average primary particle diameter is preferably 10 nm or more and 100 nm or less, and particularly preferably 10 nm. It is 50 nm or less. This average primary particle size can be obtained from a TEM photograph or the like.

  The undercoat layer is preferably formed in a form in which the metal oxide particles are dispersed in a binder resin. The binder resin used for the undercoat layer is epoxy resin, polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, polyimide resin, chloride resin. Vinylidene resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol resin, polyurethane resin, polyacrylic acid resin, polyacrylamide resin, polyvinyl pyrrolidone resin, polyvinyl pyridine resin, water-soluble polyester resin, cellulose such as nitrocellulose Ester resin, cellulose ether resin, casein, gelatin, polyglutamic acid, starch, starch acetate, amino starch, zirconium chelate compound, zirconi Organic zirconium compounds of the arm alkoxide compounds, titanyl chelate compounds, organic titanyl compounds such as titanyl alkoxide compound, may be a known binder resin such as a silane coupling agent. These can be used alone or in a cured form together with a curing agent. Among these, alcohol-soluble copolymerized polyamide, modified polyamide, and the like are preferable because they exhibit good dispersibility and coatability.

The addition ratio of the inorganic particles to the binder resin used in the undercoat layer can be arbitrarily selected. From the viewpoint of the stability of the dispersion and the coating property, the binder resin is usually 10% by mass or more, It is preferable to use in the range of 500 mass% or less.
The thickness of the undercoat layer is arbitrary as long as the effects of the present invention are not significantly impaired, but the viewpoint of improving the electrical characteristics, strong exposure characteristics, image characteristics, repeat characteristics, and coating properties during production of the electrophotographic photosensitive member. Therefore, it is usually 0.01 μm or more, preferably 0.1 μm or more, and usually 30 μm or less, preferably 20 μm or less. A known antioxidant or the like may be mixed in the undercoat layer. The undercoat layer may contain pigment particles, resin particles and the like for the purpose of preventing image defects.

<Photosensitive layer>
The photosensitive layer is formed on the above-mentioned conductive support (or on the undercoat layer when the above-described undercoat layer is provided). The photosensitive layer is a layer containing polyarylate as defined in the present application. As a type of the photosensitive layer, a charge generating substance and a charge transporting substance (including a charge transporting substance defined in the present application) are present in the same layer. A single layer structure dispersed in a binder resin (hereinafter referred to as “single layer type photosensitive layer” as appropriate), a charge generation layer in which a charge generation material is dispersed in a binder resin, and a charge transport material (as defined in this application). And a functionally separated type layered structure composed of two or more layers (including a charge transporting material dispersed in a binder resin) (hereinafter referred to as “laminated photosensitive layer” as appropriate). However, any form may be sufficient.

  In addition, as the laminated photosensitive layer, a charge-generating layer and a charge transport layer are laminated in this order from the conductive support side, and conversely, a charge transport layer and a charge generation layer are formed from the conductive support side. There are reverse laminated photosensitive layers provided in order, and any of them can be adopted, but a forward laminated photosensitive layer that can exhibit the most balanced photoconductivity is preferable.

<Functional separation type photosensitive layer>
<Charge generation layer>
The charge generation layer of the laminated photosensitive layer (function-separated type photosensitive layer) contains a charge generation material and usually contains a binder resin and other components used as necessary. Such a charge generation layer is prepared by, for example, preparing a coating solution by dissolving or dispersing fine particles of a charge generation material and a binder resin in a solvent or a dispersion medium. It can be obtained by coating and drying on the top (on the undercoat layer when an undercoat layer is provided) and on the charge transport layer in the case of a reverse laminated type photosensitive layer.

<Charge generating material>
The charge generating material may be used alone or in a mixed state with several dyes and pigments.
Examples of the charge generation material include inorganic photoconductive materials such as selenium and its alloys, cadmium sulfide, and organic photoconductive materials such as organic pigments. Organic photoconductive materials are preferred, and organic photoconductive materials are particularly preferable. Pigments are preferred. Examples of organic pigments include phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene (squarylium) pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, anthanthrone pigments, and benzimidazole pigments. . Among these, phthalocyanine pigments or azo pigments are particularly preferred as dyes used in the mixed state from the viewpoint of photosensitivity. When organic pigments are used as the charge generating substance, usually, fine particles of these organic pigments are used in the form of a dispersion layer bound with various binder resins.

  When a phthalocyanine pigment is used as the charge generating material, specifically, metal-free phthalocyanine and metal-containing phthalocyanine are used. Specific examples of metal-containing phthalocyanines include metals such as copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, germanium, or their oxides, halides, hydroxides, alkoxides, and the like. Various crystal forms of phthalocyanines are used. In particular, titanyl phthalocyanines (also known as oxytitanium phthalocyanine) such as A type (also known as β type), B type (also known as α type), D type (also known as Y type), vanadyl phthalocyanine, chloroindium phthalocyanine, which are highly sensitive crystal types Chlorogallium phthalocyanine such as type II, hydroxygallium phthalocyanine such as type V, μ-oxo-gallium phthalocyanine dimer such as type G and I, and μ-oxo-aluminum phthalocyanine dimer such as type II are suitable. is there.

  Among these phthalocyanines, A type (β type), B type (α type), D type (Y type) oxytitanium phthalocyanine, II type chlorogallium phthalocyanine, V type hydroxygallium phthalocyanine, G type μ-oxo- Gallium phthalocyanine dimer and the like are particularly preferable. In particular, oxytitanium phthalocyanine preferably has a clear diffraction peak mainly at a Bragg angle (2θ ± 0.2 °) of 27.2 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray.

  Further, the oxytitanium phthalocyanine preferably has a clear diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.7 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray. In view of the characteristics of the electrophotographic photosensitive member, main diffraction peaks at 9.6 °, 24.1 °, 27.2 °, or 9.5 °, 9.7 °, 24.1 °, and 27.2 ° are obtained. From the viewpoint of stability at the time of dispersion, it preferably has no peak at around 26.2 °. Among the oxytitanium phthalocyanines mentioned above, 7.3 °, 9.6 °, 11.6 °, 14.2 °, 18.0 °, 24.1 ° and 27.2 °, or 7.3 °, More preferably, it has main diffraction peaks at 9.5 °, 9.7 °, 11.6 °, 14.2 °, 18.0 °, 24.2 ° and 27.2 °.

  When a metal-free phthalocyanine compound or a metal-containing phthalocyanine compound is used as the charge generation material, a highly sensitive photoreceptor can be obtained with respect to a laser beam having a relatively long wavelength, for example, a laser beam having a wavelength around 780 nm. Further, when an azo pigment such as monoazo, diazo, or trisazo is used, white light, laser light having a wavelength around 660 nm, or laser light having a relatively short wavelength (for example, a wavelength in the range of 380 nm to 500 nm). It is possible to obtain a photoreceptor having sufficient sensitivity to the laser beam).

The phthalocyanine compound may be a single compound or several mixed or mixed crystal states. As the mixed state in the phthalocyanine compound or crystal state here, those obtained by mixing the respective constituent elements later may be used, or the mixed state in the production / treatment process of the phthalocyanine compound such as synthesis, pigmentation, crystallization, etc. It may be the one that gave rise to. As such treatment, acid paste treatment, grinding treatment, solvent treatment and the like are known. In order to generate a mixed crystal state, as described in JP-A-10-48859, two types of crystals are mixed, mechanically ground and made amorphous, and then converted into a specific crystal state by solvent treatment. The method of doing is mentioned.

Examples of the binder resin used for the charge generation layer in the function-separated photoreceptor include polyvinyl butyral resin, polyvinyl formal resin, partially acetalized polyvinyl butyral resin in which a part of butyral is modified with formal, acetal, etc. Polyvinyl acetal resin, polyarylate resin, polycarbonate resin, polyester resin, modified ether polyester resin, phenoxy resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, polystyrene resin, acrylic resin, methacrylic resin, polyacrylamide Resin, polyamide resin, polyvinyl pyridine resin, cellulose resin, polyurethane resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, casein, chloride Vinyl chloride-vinyl acetate, such as nyl-vinyl acetate copolymer, hydroxy-modified vinyl chloride-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer Copolymer, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, styrene-alkyd resin, silicon-alkyd resin, phenol-formaldehyde resin and other insulating resins, poly-N-vinylcarbazole, polyvinylanthracene, It can be selected from organic photoconductive polymers such as polyvinyl perylene, but is not limited to these polymers. These binder resins may be used alone or in combination of two or more.
Specifically, the charge generation layer in the function-separated type photoconductor is prepared by dispersing a charge generation material by dispersing the above-mentioned binder resin in an organic solvent and then applying the coating solution on the conductive support (with an undercoat layer). If provided, it is formed by coating (on the undercoat layer).

  Solvents used for the preparation of coating solutions and dispersion media for dissolving the binder resin include, for example, saturated aliphatic solvents such as pentane, hexane, octane and nonane, aromatic solvents such as toluene, xylene and anisole, chlorobenzene, Halogenated aromatic solvents such as dichlorobenzene and chloronaphthalene, amide solvents such as dimethylformamide and N-methyl-2-pyrrolidone, alcohol solvents such as methanol, ethanol, isopropanol, n-butanol and benzyl alcohol, glycerin, Aliphatic polyhydric alcohols such as polyethylene glycol, chain solvents such as acetone, cyclohexanone, methyl ethyl ketone, and cyclic ketone solvents, ester solvents such as methyl formate, ethyl acetate, n-butyl acetate, methylene chloride, chloroform, 1, 2-Dichro Halogenated hydrocarbon solvents such as ethane, linear ether solvents such as diethyl ether, dimethoxyethane, tetrahydrofuran, 1,4-dioxane, methylcellosolve, ethylcellosolve, acetonitrile, dimethylsulfoxide, sulfolane, hexa Examples include aprotic polar solvents such as methylphosphoric triamide, n-butylamine, isopropanolamine, diethylamine, triethanolamine, nitrogen-containing compounds such as ethylenediamine, triethylenediamine, and triethylamine, mineral oil such as ligroin, water, etc. Those which do not dissolve the undercoat layer are preferably used. These can be used alone or in combination of two or more.

In the charge generation layer of the function-separated type photoreceptor, the compounding ratio (mass) of the binder resin and the charge generation material is 10 to 1000 parts by weight, preferably 30 to 500 parts by weight with respect to 100 parts by weight of the binder resin. The film thickness is usually 0.1 μm to 10 μm, preferably 0.15 μm to 0.6 μm. If the ratio of the charge generation material is too high, the stability of the coating solution may be reduced due to aggregation of the charge generation material. On the other hand, if the ratio of the charge generating substance is too low, the sensitivity as a photoreceptor may be reduced.

  As a method for dispersing the charge generation material, a known dispersion method such as a ball mill dispersion method, an attritor dispersion method, or a sand mill dispersion method can be used. In this case, it is effective to refine the particles to a particle size of 0.5 μm or less, preferably 0.3 μm or less, more preferably 0.15 μm or less.

<Charge transport layer>
<Binder resin>
In forming a charge transport layer of a function-separated type photoreceptor having a charge generation layer and a charge transport layer and a photosensitive layer of a single layer type photoreceptor, a binder resin is used to ensure film strength. In the case of the charge transport layer of the functional separation type photoconductor, a coating solution obtained by dissolving or dispersing the charge transport material and various binder resins in a solvent, or in the case of a single layer type photoconductor, the charge generation material and the charge transport It can be obtained by applying and drying a coating solution obtained by dissolving or dispersing the substance and various binder resins in a solvent. The binder resin used in the present invention contains a polyarylate resin having a carboxylic acid terminal value of 100 μeq / g or more and 500 μeq / g or less.

If the terminal value of the carboxylic acid is too small, the effect of adhesiveness is small. If it is too large, it will be difficult to synthesize a resin having a sufficient molecular weight to give the binder the necessary strength. Therefore, it is 500 μeq / g or less, preferably 300 μeq / g or less.
The terminal value of carboxylic acid can be quantified by dissolving a precisely weighed polyarylate resin in benzyl alcohol with heating and titrating with a 0.01 N NaOH benzyl alcohol solution. The carboxylic acid terminal value in the present invention is a value measured by the <Method for Measuring Carboxylic Acid (—COOH) Terminal Value> described in the Examples, and this includes acid components such as residual monomers in the resin. There is a possibility, but they are also defined as the carboxylic acid end value.

The content of free residual monomer can be analyzed by methods such as liquid chromatograph and gas chromatograph, but the polyarylate resin produced by the usual method has a sufficient acid component due to the residual monomer relative to the carboxylic acid end value. Therefore, the carboxylic acid end value can be ignored.
As a method for obtaining a polyarylate resin having a carboxylic acid terminal value of 100 μeq / g or more and 500 μeq / g or less, in the case of a polymerization reaction using a bisphenol component and an acid halide component as substrates, Satisfying any one of A) to (D). (A) The acid halide component / phenol component molar ratio is 1.03 to 1.10 and the acid halide component is excessively used, and (B) the catalyst is excessively used as 3 to 8 mol% of the bisphenol component. (C) Polymerization under a temperature condition of 30 to 40 ° C., (D) Use of a monohydric phenol having a carboxyl group such as 4-hydroxybenzoic acid as a terminal terminator, and the like.

Among these, the method (A) in which the acid halide component is excessively used is a relatively simple method, and is preferable because it is less likely to cause a side reaction in which a component that affects electrical characteristics is generated as compared with other methods.
In the case of production by the interfacial polymerization method, for example, a solution in which a dihydric phenol compound is dissolved in an alkaline aqueous solution and a halogenated hydrocarbon solution in which an aromatic dicarboxylic acid chloride compound is dissolved are mixed. In this case, a quaternary ammonium salt or a quaternary phosphonium salt can be present as a catalyst. The polymerization temperature is preferably in the range of 0 ° C. to 40 ° C., and the polymerization time is preferably in the range of 2 hours to 20 hours from the viewpoint of productivity. After the completion of the polymerization, the water phase and the organic phase are separated, and the polymer dissolved in the organic phase is washed and recovered by a known method to obtain the intended resin.

  Examples of the alkali component used in the interfacial polymerization method include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. As the usage-amount of an alkali component, the range of 1.01 times equivalent-3 times equivalent of the phenolic hydroxyl group contained in a reaction system is preferable. Examples of the halogenated hydrocarbon include dichloromethane, chloroform, 1,2-dichloroethane, trichloroethane, tetrachloroethane, dichlorobenzene, and the like.

  Examples of the quaternary ammonium salt or quaternary phosphonium salt used as the catalyst include, for example, salts of tertiary alkylamines such as tributylamine and trioctylamine such as hydrochloric acid, bromic acid and iodic acid; benzyltriethylammonium chloride, benzyltrimethylammonium Examples include chloride, benzyltributylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium bromide, trioctylmethylammonium chloride, tetrabutylphosphonium bromide, triethyloctadecylphosphonium bromide, N-laurylpyridinium chloride, laurylpicolinium chloride It is done.

  In the interfacial polymerization method, a molecular weight regulator can be used. Examples of the molecular weight regulator include phenol, o, m, p-cresol, o, m, p-ethylphenol, o, m, p-propylphenol, o, m, p- (tert-butyl) phenol, and pentyl. Alkylphenols such as phenol, hexylphenol, octylphenol, nonylphenol, 2,6-dimethylphenol derivatives, 2-methylphenol derivatives; monofunctional phenols such as o, m, p-phenylphenol; acetic acid chloride, butyric acid chloride, octyl Examples thereof include monofunctional acid halides such as acid chloride, benzoyl chloride, benzenesulfonyl chloride, benzenesulfinyl chloride, sulfinyl chloride, benzenephosphonyl chloride and substituted products thereof. Among these molecular weight regulators, o, m, p- (tert-butyl) phenol, 2,6-dimethylphenol derivatives, 2-methylphenol derivatives are preferred because of their high molecular weight controllability and solution stability. It is. Particularly preferred are p- (tert-butyl) phenol, 2,3,6-trimethylphenol, and 2,3,5-trimethylphenol.

  Moreover, in order not to oxidize dihydric phenol in an alkaline solution, antioxidant can be added. Examples of the antioxidant include sodium sulfite, hydrosulfite (sodium hyposulfite), sulfur dioxide, potassium sulfite, sodium hydrogen sulfite and the like. Among these, hydrosulfite is particularly preferable from the viewpoint of the antioxidant effect and reduction of environmental load. As the usage-amount of antioxidant, 0.01 mass% or more and 10.0 mass% or less are preferable with respect to all the bivalent phenols. More preferably, it is 0.1 mass% or more and 5 mass% or less. If the content is too small, the antioxidant effect may be insufficient. If the content is too large, it may remain in the polyester and adversely affect electrical characteristics.

As the purification method after polymerization of the polyester resin, any method can be used as long as the effects of the present invention are not significantly impaired. For example, the polyester resin solution is an alkaline aqueous solution such as sodium hydroxide or potassium hydroxide; hydrochloric acid, An aqueous solution of acid such as nitric acid and phosphoric acid; a method of separating by standing separation, centrifugation, etc. after washing with water or the like.
Other purification methods include, for example, a method in which the produced polyester resin solution is precipitated in a solvent in which the polyester resin is insoluble, a method in which the polyester resin solution is dispersed in warm water, and the solvent is distilled off, or the polyester resin You may refine | purify by the method etc. which distribute | circulate a solution to an adsorption column etc.

  The polyester resin after purification is precipitated in water, alcohol or other organic solvent in which the polyester resin is insoluble, or the solvent of the polyester resin is distilled off in warm water or in a dispersion medium in which the polyester resin is insoluble, or heating and decompression are performed. For example, the solvent may be removed by distilling off the solvent, and when the slurry is taken out, the solid can be taken out by a centrifuge or a filter.

The obtained polyester resin is usually dried at a temperature equal to or lower than the decomposition temperature of the polyester resin, but can be preferably dried at a temperature not lower than 20 ° C. and not higher than the melting temperature of the resin. At this time, it is preferable to dry under reduced pressure.
It is preferable to perform the drying time for at least the time until the purity of impurities such as the residual solvent becomes a certain level or less. Specifically, the drying time is usually 1000 ppm or less, preferably 300 ppm or less, more preferably 100 ppm or less. dry.

  The amount of the free divalent carboxylic acid contained in the polyester resin in the present invention is not particularly limited, but is preferably 50 ppm or less, and more preferably 10 ppm or less. When the content of the free divalent carboxylic acid exceeds 50 ppm, the electrical characteristics of the photoreceptor may be deteriorated or it may become a foreign substance appearing in image evaluation. The smaller the amount of free divalent carboxylic acid, the better from the viewpoint of the electrical properties and image characteristics of the photoreceptor, but from the viewpoint of the stability of the polyester resin, it is preferably 0.01 ppm or more, and 0.1 ppm or more. It is particularly preferred that

Further, the amount of the free dihydric phenol contained in the polyester resin in the present invention is not particularly limited, but is preferably 100 ppm or less, more preferably 50 ppm or less, from the viewpoint of the electrical characteristics of the photoreceptor. From the viewpoint of simplicity of production, 0.001 ppm or more is preferable, and 0.01 ppm or more is more preferable.
The viscosity average molecular weight Mv of the polyarylate resin is not particularly limited, but the lower limit is usually 10,000 or more, preferably 15,000 or more, more preferably 40,000 or more, and the upper limit is usually 200,000 or less, preferably Is 150,000 or less, more preferably 100,000 or less. If the viscosity average molecular weight is excessively small, the mechanical strength of the photosensitive layer is lowered, which is not practical. On the other hand, if the viscosity average molecular weight is excessively large, it is difficult to apply and form the photosensitive layer to an appropriate film thickness.

  As the structure of the polyarylate resin contained in the photosensitive layer, one containing a structural unit represented by the following general formula (1) is preferable. It can be produced by a known method, for example, by polymerizing a divalent hydroxyaryl component and a dicarboxylic acid component.

(In formula (1), Ar ^{1 to} Ar ⁴ each independently represents an arylene group which may have a substituent, X represents a single bond, an oxygen atom, a sulfur atom, or an alkylene group. S represents 0. And represents an integer of 2 or less, and Y represents a single bond, an oxygen atom, a sulfur atom, or an alkylene group.
In said formula (1), Ar < ¹ > -Ar < ⁴ > represents the arylene group which may have a substituent each independently. As carbon number which an arylene group has, it is 6 or more normally, and the upper limit is 20 or less normally, Preferably it is 10 or less, More preferably, it is 6. If the number of carbon atoms is too large, the production cost increases and the electrical characteristics may deteriorate.

Specific examples of Ar ^{1 to} Ar ⁴ include 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, naphthylene group, anthrylene group, phenanthrylene group, and the like. Among these, the arylene group is preferably a 1,4-phenylene group from the viewpoint of electrical characteristics. An arylene group may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

In addition, examples of the substituent for Ar ^{1 to} Ar ⁴ include an alkyl group, an aryl group, a halogen group, and an alkoxy group. Among them, considering the mechanical properties as a binder resin for the photosensitive layer and the solubility in the coating solution for forming the photosensitive layer, the alkyl group is preferably a methyl group, an ethyl group, a propyl group, or an isopropyl group, and is preferably an aryl group. Is preferably a phenyl group or a naphthyl group, a halogen group is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, and an alkoxy group is preferably a methoxy group, an ethoxy group, a propoxy group or a butoxy group. In addition, when a substituent is an alkyl group, carbon number of the alkyl group is usually 1 or more, and usually 10 or less, preferably 8 or less, more preferably 2 or less.

More specifically, Ar ³ and Ar ⁴ each independently preferably has a substituent number of 0 or more and 2 or less, more preferably has a substituent from the viewpoint of adhesion, and among these, substitution from the viewpoint of wear resistance. It is particularly preferable that the number of groups is one. Moreover, as a substituent, an alkyl group is preferable and a methyl group is particularly preferable.
On the other hand, Ar ¹ and Ar ² each independently preferably have 0 or more and 2 or less substituents, and more preferably have no substituents from the viewpoint of wear resistance.

In the above formula (1), Y is a single bond, an oxygen atom, a sulfur atom, or an alkylene group. As the alkylene group, —CH ₂ —, —CH (CH ₃ ) —, —C (CH ₃ ) ₂ —, and cyclohexylene are preferable, and —CH ₂ —, —CH (CH ₃ ) —, — are more preferable. C (CH ₃ ) ₂ — and cyclohexylene are preferable, and —CH ₂ — and —CH (CH ₃ ) — are particularly preferable.

In the above formula (1), X is a single bond, an oxygen atom, a sulfur atom, or an alkylene group, and among them, X is an oxygen atom. This is preferable because the influence on the characteristics is reduced. In that case, it is preferable that s is 0 or 1 because the raw material is easily available, and 1 is preferable for durability of the photoreceptor.
Specific examples of preferred dicarboxylic acid residues when s is 1 include diphenyl ether-2,2′-dicarboxylic acid residues, diphenyl ether-2,3′-dicarboxylic acid residues, and diphenyl ether-2,4′-dicarboxylic acid. Residue, diphenyl ether-3,3′-dicarboxylic acid residue, diphenyl ether-3,4′-dicarboxylic acid residue, diphenyl ether-4,4′-dicarboxylic acid residue and the like. Among these, considering the simplicity of production of the dicarboxylic acid component, diphenyl ether-2,2′-dicarboxylic acid residue, diphenyl ether-2,4′-dicarboxylic acid residue, diphenyl ether-4,4′-dicarboxylic acid Residues are more preferred, and diphenyl ether-4,4′-dicarboxylic acid residues are particularly preferred.

Specific examples of the dicarboxylic acid residue when s is 0 include phthalic acid residue, isophthalic acid residue, terephthalic acid residue, toluene-2,5-dicarboxylic acid residue, p-xylene-2,5- Dicarboxylic acid residue, naphthalene-1,4-dicarboxylic acid residue, naphthalene-2,3-dicarboxylic acid residue, naphthalene-2,6-dicarboxylic acid residue, biphenyl-2,2′-dicarboxylic acid residue, Biphenyl-4,4′-dicarboxylic acid residue may be mentioned, preferably phthalic acid residue, isophthalic acid residue, terephthalic acid residue, naphthalene-1,4-dicarboxylic acid residue, naphthalene-2,6- Dicarboxylic acid residues, biphenyl-2,2′-dicarboxylic acid residues, biphenyl-4,4′-dicarboxylic acid residues, particularly preferably isophthalic acid residues and terephthalic acid residues. It is also possible to use a combination of a plurality of rubonic acid residues. Preferable specific examples include polyarylate resins having structural units represented by the following formulas (3) and (4). In the formulas (3) and (4), the ratio of the isophthalic acid residue to the terephthalic acid residue is usually 50:50, but can be arbitrarily changed. In that case, the higher the ratio of terephthalic acid residues, the better from the viewpoint of electrical characteristics.

In addition, when it has a repeating structure of Formula (1) and another repeating structure, it is preferable that the repeating structure of Formula (1) is 70% or more as the number of repeating units, and more preferably 80% or more. It is preferably 90% or more. Particularly preferred is the case having only the repeating structure of the formula (1), that is, the case where the repeating structure constituting the present invention is 100% as the number of repeating units.
What is preferable as a structural unit which polyarylate resin has is described below. The structural unit that the polyarylate resin may have is not limited to the structure described below. Moreover, 1 type of the following structure may be included independently and 2 or more types may be included in arbitrary ratios and combinations.
・ Repeated structure when k is 0

・ Repeated structure when k is 1

<Charge transport material>
As the charge transport material, a triphenylamine compound is contained in the photosensitive layer (charge transport layer). Since the triphenylamine compound is chemically stable, the charge transport ability can be exhibited without being influenced by the carboxylic acid terminal of the polyarylate resin of the present invention. As long as it is a compound containing a triphenylamine structure, it is not particularly limited, and any substance can be used. Examples of known charge transport materials include aromatic nitro compounds such as 2,4,7-trinitrofluorenone, cyano compounds such as tetracyanoquinodimethane, electron withdrawing materials such as quinone compounds such as diphenoquinone, and carbazole derivatives. , Indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, thiadiazole derivatives, heterocyclic compounds such as benzofuran derivatives, aniline derivatives, hydrazone derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, and combinations of these compounds Or an electron donating substance such as a polymer having a group consisting of these compounds in the main chain or side chain. Among these, carbazole derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, and those in which a plurality of these compounds are bonded are preferable because they are not easily affected by carboxylic acid terminals. Any one of these charge transport materials may be used alone, or two or more thereof may be used in any combination.

Preferred specific examples of the charge transport material are shown below. In the following compounds, R may be the same or different. Specifically, a hydrogen atom, an alkyl group, an alkoxy group, a phenyl group, an arylalkyl and the like are preferable. Particularly preferred is a methyl group, an ethyl group or a benzyl group. N is an integer of 0 or more and 2 or less.
The following examples are specific examples of the charge transport material, and other charge transport materials are not limited to the following.

  As the charge transport material, the following compounds are preferable from the viewpoint of mobility. By spreading the π-conjugated system, it is possible to obtain a photoconductor having high electron transport ability, and particularly having both electrical properties and adhesiveness when combined with the polyarylate resin of the present application.

  The ratio of the binder resin to the charge transport material is preferably 20 parts by mass or more with respect to 100 parts by mass of the binder resin for both the single layer type and the laminated type, and preferably 30 parts by mass or more from the viewpoint of reducing the residual potential. From the viewpoint of stability and charge mobility, 40 parts by mass or more is more preferable. On the other hand, from the viewpoint of thermal stability of the photosensitive layer, it is usually 150 parts by mass or less, preferably 100 parts by mass or less from the viewpoint of compatibility between the charge transport material and the binder resin, and from the viewpoint of printing durability. 70 parts by mass or less is more preferable, and from the viewpoint of scratch resistance, 50 parts by mass or less is particularly preferable. In particular, when the amount of the charge transport material is 50 parts by mass or less, the shrinkage of the photosensitive layer becomes remarkable and the photosensitive layer is likely to float. In addition, since the surface of the photosensitive layer is flatter, the anchor effect cannot be obtained, so the adhesiveness is likely to deteriorate, and in combination with the polyarylate resin of the present application, the poor electrical properties due to the deterioration of the adhesiveness are suppressed. can do.

  In the case of a multilayer photoreceptor, the thickness of the charge transport layer is not particularly limited, but is usually 5 μm or more, preferably 10 μm or more, and usually 50 μm or less from the viewpoint of long life, image stability, and high resolution. , Preferably 45 μm or less, more preferably 30 μm or less.

<Single layer type photosensitive layer>
The single-layer type photosensitive layer is formed using a binder resin in the same manner as the charge transport layer of the function-separated type photoreceptor in addition to the charge generation material and the charge transport material. Specifically, a charge generation material, a charge transport material, and various binder resins are dissolved or dispersed in a solvent to prepare a coating solution, and on a conductive support (on the undercoat layer when an undercoat layer is provided). It can be obtained by coating and drying.
The types of the charge transport material and the binder resin and the use ratios thereof are the same as those described for the charge transport layer of the multilayer photoreceptor. A charge generating material is further dispersed in a charge transport medium comprising these charge transport materials and a binder resin.
As the charge generation material, the same materials as those described for the charge generation layer of the multilayer photoreceptor can be used. However, in the case of a photosensitive layer of a single layer type photoreceptor, it is necessary to sufficiently reduce the particle size of the charge generating material. Specifically, the range is usually 1 μm or less, preferably 0.5 μm or less.

If the amount of the charge generating material dispersed in the single-layer type photosensitive layer is too small, sufficient sensitivity cannot be obtained, but if it is too large, there are adverse effects such as a decrease in chargeability and a decrease in sensitivity. The total amount of the layer-type photosensitive layer is usually 0.5% by mass or more, preferably 1% by mass or more, and usually 50% by mass or less, preferably 20% by mass or less.
In addition, the usage ratio of the binder resin and the charge generation material in the single-layer type photosensitive layer is such that the charge generation material is usually 0.1 parts by weight or more, preferably 1 part by weight or more, based on 100 parts by weight of the binder resin. It is 30 mass parts or less, Preferably it is set as the range of 10 mass parts or less.

The film thickness of the single-layer type photosensitive layer is usually 5 μm or more, preferably 10 μm or more, and usually 100 μm or less, preferably 50 μm or less.
In addition, in both the multilayer type photoreceptor and the single layer type photoreceptor, the film forming property, flexibility, coating property, stain resistance, gas resistance, light resistance, etc. are improved for the photosensitive layer or each layer constituting the photosensitive layer. For the purpose, a known antioxidant, plasticizer, ultraviolet absorber, electron-withdrawing compound, leveling agent, visible light shielding agent and the like may be contained.

<Other functional layers>
In a laminated or single layer type photoreceptor, a protective layer is provided on the outermost layer for the purpose of preventing the photosensitive layer from being worn and preventing or reducing the deterioration of the photosensitive layer due to discharge substances generated from a charger or the like. May be. The protective layer is formed by containing a conductive material in an appropriate binder resin, or charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 and JP-A-10-252377. The copolymer using the compound which has can be used.

Examples of the conductive material used for the protective layer include aromatic amino compounds such as TPD (N, N′-diphenyl-N, N′-bis- (m-tolyl) benzidine), antimony oxide, indium oxide, tin oxide, and oxide. Metal oxides such as titanium, tin oxide-antimony oxide, aluminum oxide, and zinc oxide can be used, but are not limited thereto.
As the binder resin used for the protective layer, known resins such as polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, and siloxane resin can be used. Further, a copolymer of the above resin with a skeleton having a charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 can also be used. As the polyarylate resin in the photosensitive layer of the present application, thermoplastic polyamide resin, polyester resin, and polycarbonate resin can be used because of good adhesion.
The electrical resistance of the protective layer is usually in the range of 10 ⁹ Ω · cm to 10 ¹⁴ Ω · cm. When the electric resistance is higher than the range, the residual potential is increased, resulting in an image with much fogging. On the other hand, when the electric resistance is lower than the range, the image is blurred and the resolution is reduced. Further, the protective layer must be configured so as not to substantially prevent transmission of light irradiated during image exposure.

  Further, for the purpose of reducing the frictional resistance and wear on the surface of the photoconductor, and increasing the transfer efficiency of the toner from the photoconductor to the transfer belt and paper, etc., the surface layer is made of a fluororesin, silicone resin, polyethylene resin, or the like. You may contain the particle | grains which consist of these resin, and the particle | grains of an inorganic compound. Alternatively, a layer containing these resins and particles may be newly formed as a surface layer.

<Method for forming each layer>
Each layer constituting the above-described photoreceptor is formed by dip coating, spray coating, nozzle coating, bar coating, roll coating, blade coating on a conductive support obtained by dissolving or dispersing a substance to be contained in a solvent. It is formed by repeating a coating / drying step sequentially for each layer by a known method such as coating.

  There are no particular restrictions on the solvent or dispersion medium used in the preparation of the coating solution, but specific examples include alcohols such as methanol, ethanol, propanol and 2-methoxyethanol, tetrahydrofuran, 1,4-dioxane, dimethoxyethane and the like. Ethers, esters such as methyl formate and ethyl acetate, acetone, methyl ethyl ketone, cyclohexanone, ketones such as 4-methoxy-4-methyl-2-pentanone, aromatic hydrocarbons such as benzene, toluene, xylene, dichloromethane, Chlorinated hydrocarbons such as chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene, n-butylamine, isopropanolamine, Diethyla Emissions, triethanolamine, ethylenediamine, nitrogen-containing compounds such as triethylenediamine, acetonitrile, N- methylpyrrolidone, N, N- dimethylformamide, aprotic polar solvents such as dimethyl sulfoxide and the like. Moreover, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and kinds.

The amount of the solvent or dispersion medium used is not particularly limited, but considering the purpose of each layer and the properties of the selected solvent / dispersion medium, it is appropriate so that the physical properties such as solid content concentration and viscosity of the coating liquid are within a desired range. It is preferable to adjust.
For example, in the case of a charge transport layer of a single layer type photoreceptor or a function separation type photoreceptor, the solid content concentration of the coating solution is usually 5% by mass or more, preferably 10% by mass or more, and usually 40% by mass or less. The range is preferably 35% by mass or less. In addition, the viscosity of the coating solution is usually 10 mPa · s or higher, preferably 50 mPa · s or higher, and usually 500 mPa · s or lower, preferably 400 mPa · s or lower, at the temperature during use.

  In the case of a charge generation layer of a multilayer photoreceptor, the solid content concentration of the coating solution is usually 0.1% by mass or more, preferably 1% by mass or more, and usually 15% by mass or less, preferably 10% by mass. % Or less. In addition, the viscosity of the coating solution is usually 0.01 mPa · s or higher, preferably 0.1 mPa · s or higher, and usually 20 mPa · s or lower, preferably 10 mPa · s or lower, at the temperature during use.

  Each layer constituting these photoconductors is formed by applying the coating solution obtained by the above-described method on a support using a known coating method, repeating the coating and drying steps for each layer, and sequentially coating the layers. The Examples of the coating method include a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a wire bar coating method, a blade coating method, a roller coating method, an air knife coating method, and a curtain coating method. Other known coating methods can also be used.

  The coating solution is preferably dried by touching at room temperature, followed by heating or drying in a temperature range of usually 30 ° C. or more and 200 ° C. or less for 1 minute to 2 hours, while still or blowing. Further, the heating temperature may be constant, or heating may be performed while changing the temperature during drying.

[Image forming equipment]
Next, an embodiment of an image forming apparatus using the electrophotographic photosensitive member of the present invention (an image forming apparatus of the present invention) will be described with reference to FIG. However, the embodiment is not limited to the following description, and can be arbitrarily modified without departing from the gist of the present invention.

As shown in FIG. 1, the image forming apparatus includes an electrophotographic photosensitive member 1, a charging device 2, an exposure device 3, and a developing device 4, and further, a transfer device 5, a cleaning device 6 and a fixing device as necessary. A device 7 is provided.
The electrophotographic photoreceptor 1 is not particularly limited as long as it is the above-described electrophotographic photoreceptor of the present invention, but in FIG. 1, as an example, a drum in which the above-described photosensitive layer is formed on the surface of a cylindrical conductive support. The photoconductor is shown. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are disposed along the outer peripheral surface of the electrophotographic photosensitive member 1.

The charging device 2 charges the electrophotographic photosensitive member 1 and uniformly charges the surface of the electrophotographic photosensitive member 1 to a predetermined potential. Examples of the charging device include a corona charging device such as a corotron and a scorotron, a direct charging device (contact type charging device) that charges a direct charging member to which a voltage is applied by contacting the photosensitive member surface, and a contact type charging device such as a charging brush. Often used. Examples of direct charging means include contact chargers such as charging rollers and charging brushes. In FIG. 1, a roller-type charging device (charging roller) is shown as an example of the charging device 2. As the direct charging means, either charging with air discharge or injection charging without air discharge is possible. Moreover, as a voltage applied at the time of charging, it is possible to use only a direct current voltage or to superimpose an alternating current on a direct current.

  The type of the exposure apparatus 3 is not particularly limited as long as it can expose the electrophotographic photoreceptor 1 to form an electrostatic latent image on the photosensitive surface of the electrophotographic photoreceptor 1. Specific examples include halogen lamps, fluorescent lamps, lasers such as semiconductor lasers and He—Ne lasers, LEDs, and the like. Further, exposure may be performed by a photoreceptor internal exposure method. The light used for the exposure is arbitrary. For example, the exposure may be performed using monochromatic light with a wavelength of 780 nm, monochromatic light with a wavelength slightly shorter than 600 nm to 700 nm, or monochromatic light with a short wavelength of 380 nm to 500 nm. . Among these, it is preferable to use light having a short wavelength of 380 to 500 nm because the resolution becomes high. Among these, 405 nm monochromatic light is preferable.

  The type of the developing device 4 is not particularly limited, and an arbitrary device such as a dry development method such as cascade development, one-component insulating toner development, one-component conductive toner development, or two-component magnetic brush development, or a wet development method is used. be able to. In FIG. 1, the developing device 4 includes a developing tank 41, an agitator 42, a supply roller 43, a developing roller 44, and a regulating member 45, and has a configuration in which toner T is stored inside the developing tank 41. . Further, a replenishing device (not shown) for replenishing the toner T may be attached to the developing device 4 as necessary. The replenishing device is configured to be able to replenish toner T from a container such as a bottle or a cartridge.

The supply roller 43 is formed from a conductive sponge or the like. The developing roller 44 is made of a metal roll such as iron, stainless steel, aluminum, or nickel, or a resin roll obtained by coating such a metal roll with a silicon resin, a urethane resin, a fluorine resin, or the like. The surface of the developing roller 44 may be smoothed or roughened as necessary.
The developing roller 44 is disposed between the electrophotographic photoreceptor 1 and the supply roller 43 and is in contact with the electrophotographic photoreceptor 1 and the supply roller 43, respectively. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism (not shown). The supply roller 43 carries the stored toner T and supplies it to the developing roller 44. The developing roller 44 carries the toner T supplied by the supply roller 43 and contacts the surface of the electrophotographic photosensitive member 1.

  The regulating member 45 is formed of a resin blade such as silicon resin or urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or a blade obtained by coating such a metal blade with resin. The regulating member 45 contacts the developing roller 44 and is pressed against the developing roller 44 side with a predetermined force by a spring or the like (a general blade linear pressure is 5 to 500 g / cm). If necessary, the regulating member 45 may be provided with a function of imparting charging to the toner T by frictional charging with the toner T.

The agitator 42 is rotated by a rotation driving mechanism, and agitates the toner T and conveys the toner T to the supply roller 43 side. A plurality of agitators 42 may be provided with different blade shapes and sizes.
The type of the transfer device 5 is not particularly limited, and an apparatus using an arbitrary system such as an electrostatic transfer method such as corona transfer, roller transfer, or belt transfer, a pressure transfer method, or an adhesive transfer method can be used. . Here, it is assumed that the transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like that are disposed to face the electrophotographic photoreceptor 1. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charging potential of the toner T, and transfers the toner image formed on the electrophotographic photosensitive member 1 to a recording paper (paper, medium) P. Is.

There is no restriction | limiting in particular about the cleaning apparatus 6, Arbitrary cleaning apparatuses, such as a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, can be used. The cleaning device 6 is for scraping off residual toner adhering to the photoreceptor 1 with a cleaning member and collecting the residual toner. However,
If there is little or almost no toner remaining on the surface of the photoreceptor, the cleaning device 6 may be omitted.

  The fixing device 7 includes an upper fixing member (fixing roller) 71 and a lower fixing member (fixing roller) 72, and a heating device 73 is provided inside the fixing member 71 or 72. FIG. 1 shows an example in which a heating device 73 is provided inside the upper fixing member 71. Each of the upper and lower fixing members 71 and 72 includes a fixing roll in which a metal base tube such as stainless steel or aluminum is coated with silicon rubber, a fixing roll in which Teflon (registered trademark) resin is coated, and a fixing sheet. A member can be used. Further, each of the fixing members 71 and 72 may be configured to supply a release agent such as silicone oil in order to improve releasability, or may be configured to forcibly apply pressure to each other by a spring or the like.

When the toner transferred onto the recording paper P passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the toner is heated to a molten state and cooled after passing through the recording paper. Toner is fixed on P.
The type of the fixing device is not particularly limited, and a fixing device of any type such as heat roller fixing, flash fixing, oven fixing, pressure fixing, etc. can be provided including those used here.

In the electrophotographic apparatus configured as described above, an image is recorded as follows. That is, first, the surface (photosensitive surface) of the photoreceptor 1 is charged to a predetermined potential (for example, −600 V) by the charging device 2. At this time, charging may be performed by a DC voltage, or charging may be performed by superimposing an AC voltage on the DC voltage.
Subsequently, the photosensitive surface of the charged photoreceptor 1 is exposed by the exposure device 3 according to the image to be recorded, and an electrostatic latent image is formed on the photosensitive surface. The developing device 4 develops the electrostatic latent image formed on the photosensitive surface of the photoreceptor 1.

The developing device 4 thins the toner T supplied by the supply roller 43 with a regulating member (developing blade) 45 and has a predetermined polarity (here, the same polarity as the charging potential of the photosensitive member 1) and the negative polarity. ), And conveyed while being carried on the developing roller 44 to be brought into contact with the surface of the photoreceptor 1.
When the charged toner T carried on the developing roller 44 comes into contact with the surface of the photoreceptor 1, a toner image corresponding to the electrostatic latent image is formed on the photosensitive surface of the photoreceptor 1. This toner image is transferred onto the recording paper P by the transfer device 5. Thereafter, the toner remaining on the photosensitive surface of the photoreceptor 1 without being transferred is removed by the cleaning device 6.

After the transfer of the toner image onto the recording paper P, the final image is obtained by passing the fixing device 7 and thermally fixing the toner image onto the recording paper P.
In addition to the above-described configuration, the image forming apparatus may have a configuration capable of performing, for example, a static elimination process. The neutralization step is a step of neutralizing the electrophotographic photosensitive member by exposing the electrophotographic photosensitive member, and a fluorescent lamp, an LED, or the like is used as the neutralizing device. In addition, the light used in the static elimination process is often light having an exposure energy that is at least three times that of the exposure light.

The image forming apparatus may be further modified. For example, the image forming apparatus may be configured to perform a pre-exposure process, an auxiliary charging process, or the like, or may be configured to perform offset printing. A full-color tandem system configuration using toner may be used.
The electrophotographic photosensitive member 1 is combined with one or more of the charging device 2, the exposure device 3, the developing device 4, the transfer device 5, the cleaning device 6, and the fixing device 7 to form an integrated cartridge ( The electrophotographic photosensitive member cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. In this case, for example, when the electrophotographic photosensitive member 1 and other members are deteriorated, the electrophotographic photosensitive member cartridge is removed from the main body of the image forming apparatus, and another new electrophotographic photosensitive member cartridge is mounted on the main body of the image forming apparatus. This facilitates maintenance and management of the image forming apparatus.

  Hereinafter, the present invention will be described in more detail with reference to production examples, examples and comparative examples. In addition, the following examples are shown in order to explain the present invention in detail, and the present invention is not limited to the following examples unless it is contrary to the gist thereof.

Production Example 1 (Resin A1)
In a 1000 mL beaker, 19.84 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. Thereto was added 48.72 g of 1,1-bis (3-methyl-4-hydroxyphenyl) ethane, stirred and dissolved, and then the aqueous alkaline solution was transferred to a 2 L reaction vessel. Next, 0.5409 g of benzyltriethylammonium chloride and 1.4539 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 65.92 g of diphenyl ether-4,4′-dicarboxylic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the alkaline aqueous solution in the reaction tank, the dichloromethane solution was dropped from the dropping funnel over 1 hour. After further stirring for 5 hours, 783 mL of dichloromethane was added and stirring was continued for 7 hours. Thereafter, 8.10 mL of acetic acid was added and stirred for 30 minutes, then stirring was stopped and the organic layer was separated. This organic layer was washed twice with 942 mL of a 0.1N aqueous sodium hydroxide solution, then washed twice with 942 mL of 0.1N hydrochloric acid, and further washed twice with 942 mL of water. The organic layer after washing was poured into 6266 mL of methanol, and the resulting precipitate was removed by filtration and dried to obtain Resin A1. The unit structure of Resin A1 is shown below. The viscosity average molecular weight of this resin was 37200.

Production Example 2 (Resin A2)
In a 1000 mL beaker, 20.41 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. To this, 50.12 g of 1,1-bis (3-methyl-4-hydroxyphenyl) ethane was added, stirred and dissolved, and the aqueous alkaline solution was transferred to a 2 L reaction vessel. Next, 0.5564 g of benzyltriethylammonium chloride and 1.4956 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 64.04 g of diphenyl ether-4,4′-dicarboxylic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin A2. The viscosity average molecular weight of Resin A2 was 45100.

Production Example 3 (Resin A3)
In a 1000 mL beaker, 20.59 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. To this, 50.55 g of 1,1-bis (3-methyl-4-hydroxyphenyl) ethane was added, stirred and dissolved, and then the aqueous alkaline solution was transferred to a 2 L reaction vessel. Next, 0.5612 g of benzyltriethylammonium chloride and 2,3,5-
1.5086 g of trimethylphenol was sequentially added to the reaction vessel. Separately, a mixed solution of 63.46 g of diphenyl ether-4,4′-dicarboxylic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin A3. The viscosity average molecular weight of Resin A3 was 39600.

Production Example 4 (Resin A4)
In a 1000 mL beaker, 19.66 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. Thereto was added 48.27 g of 1,1-bis (3-methyl-4-hydroxyphenyl) ethane, stirred and dissolved, and then the aqueous alkaline solution was transferred to a 2 L reaction vessel. Next, 0.5359 g of benzyltriethylammonium chloride and 1.4405 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 66.52 g of diphenyl ether-4,4′-dicarboxylic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin A4. The viscosity average molecular weight of Resin A4 was 37100.

Production Example 5 (Resin B1)
In a 1000 mL beaker, 24.20 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. Thereto, 63.21 g of 2,2-bis (3-methyl-4-hydroxyphenyl) propane was added, stirred and dissolved, and then the aqueous alkaline solution was transferred to a 2 L reaction vessel. Next, 0.6564 g of benzyltriethylammonium chloride and 1.4105 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 27.38 g of terephthalic acid chloride, 27.38 g of isophthalic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin B1. The unit structure of resin B1 is shown below. The viscosity average molecular weight of the resin B1 was 17500.

Production Example 6 (Resin B2)
In a 1000 mL beaker, 24.77 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. Thereto, 64.69 g of 2,2-bis (3-methyl-4-hydroxyphenyl) propane was added, stirred and dissolved, and then this alkaline aqueous solution was transferred to a 2 L reaction vessel. Next, 0.6717 g of benzyltriethylammonium chloride and 1.4434 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 26.24 g of terephthalic acid chloride, 26.24 g of isophthalic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin B2. Resin B2 had a viscosity average molecular weight of 34,000.

Production Example 7 (Resin C1)
In a 1000 mL beaker, 20.98 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. Thereto, 20.67 g of 1,1-bis (3-methyl-4-hydroxyphenyl) ethane and 25.63 g of bis (4-hydroxyphenyl) methane were added, stirred and dissolved, and then this aqueous alkaline solution was placed in a 2 L reactor. Moved. Next, 0.5704 g of benzyltriethylammonium chloride and 1.3650 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 69.59 g of diphenyl ether-4,4′-dicarboxylic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin C1. The unit structure of the resin C1 is shown below. The viscosity average molecular weight of the resin C1 was 33600.

Production Example 8 (Resin C2)
In a 1000 mL beaker, 21.71 g of sodium hydroxide and 940 mL of water were weighed and dissolved while stirring. Thereto, 21.39 g of 1,1-bis (3-methyl-4-hydroxyphenyl) ethane and 26.52 g of bis (4-hydroxyphenyl) methane were added, stirred and dissolved, and then this alkaline aqueous solution was put into a 2 L reactor. Moved. Next, 0.5902 g of benzyltriethylammonium chloride and 1.4124 g of 2,3,5-trimethylphenol were sequentially added to the reaction vessel. Separately, a mixed solution of 67.43 g of diphenyl ether-4,4′-dicarboxylic acid chloride and 470 mL of dichloromethane was transferred into the dropping funnel. Thereafter, the same operation as in Production Example 1 was performed to obtain Resin C2. The viscosity average molecular weight of Resin C2 was 40300.

<Method for measuring the amount of terminal carboxylic acid (—COOH) group>
About 0.4 g of polyarylate resin was precisely weighed in a tall beaker, 25 mL of benzyl alcohol was added and dissolved by heating in an oil bath at 195 ° C. After confirming complete dissolution, the solution was removed from the oil bath and cooled. After cooling, 2 mL of ethyl alcohol was gently introduced along the wall of the tall beaker.

This solution was titrated with a 0.01N NaOH benzyl alcohol solution using an automatic titrator (GT100, manufactured by Mitsubishi Chemical).
Separately, only the solvent benzyl alcohol was titrated with a 0.01 N NaOH benzyl alcohol solution to obtain a blank value.
Moreover, the factor of 0.01N-NaOH benzyl alcohol solution was calculated | required with the following method.
(1) 0.1N hydrochloric acid (HCL) (volumetric reagent 10 mL of a known defined solution (FHCL) was accurately placed in a 100 mL volumetric flask with a whole pipette, aligned with a marked line with demineralized water, and mixed uniformly.
(2) Weigh 1, 2, 4 mL of the prepared solution of (1) accurately in a tall beaker for titration with a whole pipette.
(3) Add 25 mL of benzyl alcohol and 2 mL of ethyl alcohol to each.
(4) Using an automatic titrator (GT100, manufactured by Mitsubishi Chemical), titration was performed with a 0.01N NaOH benzyl alcohol solution.
(5) Calculation: The amount of NaOH benzyl alcohol titration solution (Y-axis) against the amount of hydrochloric acid adjustment solution (X-axis) in (1) is plotted.
Factor N of 0.01N-NaOH benzyl alcohol solution = FHCL / S
[Calculation]
Terminal COOH group (μeq / g) = {(A−B) × F × 10} / W
A: Measurement titration volume (mL)
B: Blank titration (mL)
F: Factor of 0.01N NaOH benzyl alcohol solution W: Polyarylate resin amount (g)
The carboxylic acid terminal values of the resins A1 to A4, B1 to B2, and C1 to C2 are shown in Table 1 below.

<Manufacture of photoconductor for electrical property evaluation>
Example 1 (photosensitive member X1)
Using a conductive support in which an aluminum vapor-deposited layer (thickness 700 mm) is formed on the surface of a biaxially stretched polyethylene terephthalate resin film (thickness 75 μm), the following undercoat layer dispersion is applied on the vapor-deposited layer of the support: Using a bar coater, the film thickness after drying was applied to 1.25 μm and dried to form an undercoat layer.

  A slurry obtained by mixing a rutile type titanium oxide having an average primary particle size of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by mass of methyldimethoxysilane with respect to the titanium oxide in a ball mill is dried, and further methanol is added. The hydrophobically treated titanium oxide obtained by washing and drying in (1) was dispersed in a methanol / 1-propanol mixed solvent by a ball mill to form a hydrophobized titanium oxide dispersion slurry, and the dispersed slurry, methanol / 1-propanol / toluene (mass ratio 7/1/2) mixed solvent, and ε-caprolactam / bis (4-amino-3-methylphenyl) methane / hexamethylenediamine / decamemethylene dicarboxylic acid / octadecamethylene Copolymer polyamid comprising dicarboxylic acid (composition mol% 75 / 9.5 / 3 / 9.5 / 3) The pellets were stirred and mixed with heating to dissolve the polyamide pellets, and then subjected to ultrasonic dispersion treatment, whereby the solid content concentration containing hydrophobically treated titanium oxide / copolymerized polyamide at a mass ratio of 3/1 was 18 A dispersion of 0.0% was obtained.

As a charge generation material, 20 parts of titanium oxyphthalocyanine having a powder X-ray diffraction spectrum pattern with respect to CuKα characteristic X-ray shown in FIG. 2 (D type) and 280 parts of 1,2-dimethoxyethane are mixed, and 2 hours in a sand grind mill. The mixture was pulverized and dispersed. Subsequently, 500 parts of a 4% 1,2-dimethoxyethane solution of polyvinyl butyral and 200 parts of 1,2-dimethoxyethane were mixed to prepare a dispersion. This dispersion was applied onto the undercoat layer with a bar coater to form a charge generation layer so that the film thickness after drying was 0.4 μm.

Next, on this film, a mixture (CTM-1) produced by the method described in Example 1 of JP-A-2002-080432, comprising a group of geometric isomers having the following structure as a main component And 100 parts of resin A1 (COOH value 159 μeq / g), antioxidant (Irganox 1076: 3- (3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate) 8 parts, and 0.05 parts of silicone oil as a leveling agent in 640 parts of a tetrahydrofuran / toluene (8/2) mixed solvent were applied and dried at 125 ° C. for 20 minutes. A charge transport layer was provided so as to have a thickness of 25 μm to prepare a photoconductor. This photoreceptor is referred to as a photoreceptor X1.

Comparative Example 1 (Photoconductor X2)
Comparative Example 2 (Photoreceptor X3) in which Photoreceptor X2 was prepared in the same manner as Example 1 except that Resin A2 (COOH value 53 μeq / g) was used instead of Resin A1.
A photoconductor produced in the same manner as in Example 1 except that resin A3 (COOH value 24 μeq / g) was used instead of resin A1 was designated as photoconductor X3.

<Evaluation of electrical characteristics of photoconductor>
Using an electrophotographic characteristic evaluation apparatus (basic and applied electrophotographic technology, edited by the Electrophotographic Society, Corona, pages 404-405) prepared according to the Electrophotographic Society measurement standard, the photoconductor is made into an aluminum drum. Attached to a cylindrical shape, the aluminum drum and the aluminum base of the photoconductor are connected, and then the drum is rotated at a constant rotational speed, and an electrical property evaluation test is performed by a cycle of charging, exposure, potential measurement, and static elimination. went.

  At that time, the initial surface potential was −700 V, exposure was 780 nm, and charge removal was monochromatic light of 660 nm. As the surface potential (VL) when 780 nm light was irradiated at 1.0 μJ / cm 2 and the index representing sensitivity, the exposure amount (half exposure amount) required to halve the surface potential to −350 V was measured. In the VL measurement, the time required for the exposure-potential measurement was 100 ms. The measurement environment was a temperature of 25 ° C. and a relative humidity of 50%. It shows that an electrical property is so favorable that the absolute value of the value of a sensitivity (half exposure amount) and VL is small. The results of electrical characteristics are shown in Table-2.

<Manufacture of photoconductor for adhesion test>
Example 2 (Photoconductor Y1)
Instead of polyethylene vapor-deposited polyethylene terephthalate film, an aluminum plate with a thickness of 0.5 mm was used, and the same charge generation layer and charge transport layer as in Example 1 were formed directly on the substrate without an undercoat layer. A photoconductor Y1 for property test was prepared.

Comparative Example 3 (Photoconductor Y2)
In place of the aluminum-deposited polyethylene terephthalate film, an aluminum plate having a thickness of 0.5 mm was used, and the same charge generation layer and charge transport layer as those in Comparative Example 1 were directly formed on the substrate without an undercoat layer and bonded. A photoconductor Y2 for property test was prepared.

Comparative Example 4 (Photoconductor Y3)
Instead of the aluminum-deposited polyethylene terephthalate film, the same charge generation layer and charge transport layer as those of Comparative Example 2 were formed directly on the substrate without using an undercoat layer on an aluminum plate having a thickness of 0.5 mm, and adhesiveness Test photoconductor Y3 was prepared.

<Adhesion test>
On this adhesion test photoreceptor, an NT cutter was used to cut 6 pieces vertically and 6 pieces horizontally at intervals of 2 mm to produce 5 × 5 25 squares. Cellotape (registered trademark) (manufactured by Nichiban Co., Ltd.) was applied from above, and the adhesion of the photosensitive layer was tested by pulling it up to 90 ° with respect to the adhesion surface. This was carried out at two locations, and the number of photosensitive layers remaining on the support out of the total of 50 spaces was defined as the number of remaining cells. The greater the residual mass number, the better the adhesion. The results are shown in Table-3.

Example 3 (photoreceptor Y4)
In the same manner as in Example 2, a photoreceptor prepared by using resin A4 (COOH value 215 μeq / g) instead of resin A1 is referred to as photoreceptor Y4.

Example 4 (photoreceptor Y5)
In the same manner as in Example 2, a photoconductor prepared using a mixture (mass ratio 3/7) of resin A3 and A4 (average COOH value 158 μeq / g) instead of resin A1 is referred to as photoconductor Y5.

Comparative Example 5 (Photoreceptor Y6)
These photoconductors were prepared in the same manner as in Example 2 using a mixture of the resins A3 and A4 (mass ratio 8/2) (average COOH value 62 μeq / g) instead of the resin A1. The adhesion test was carried out in the same manner as described above using three photoreceptors Y4-6. The results are shown in Table-4.

Example 5 (photoreceptor Y7)
The following charge generation layer and charge transport layer were formed on an aluminum plate having a thickness of 0.5 mm to prepare a photoreceptor for adhesion test. As a charge generation material, powder X against CuKα characteristic X-rays shown in FIG. 20 parts of titanium oxyphthalocyanine having a line diffraction spectrum pattern and 280 parts of 1,2-dimethoxyethane were mixed and pulverized with a sand grind mill for 2 hours for atomization dispersion treatment. Subsequently, 250 parts of a 4% 1,2-dimethoxyethane solution of polyvinyl butyral and 450 parts of 1,2-dimethoxyethane were mixed to prepare a dispersion. This dispersion was applied onto the aluminum plate with a bar coater to form a charge generation layer so that the film thickness after drying was 0.4 μm.

Next, 50 parts of the mixture (CTM-1) used in Example 1 as a charge transport material, 100 parts of resin B1 (COOH value 191 μeq / g), an antioxidant (Irganox 1076: 3- ( 8 parts of 3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate) and 0.05 parts of silicone oil as a leveling agent were dissolved in 640 parts of a tetrahydrofuran / toluene (8/2) mixed solvent. The solution was applied onto the charge generation layer, dried at 125 ° C. for 20 minutes, and a charge transport layer was provided so that the film thickness after drying was 25 μm to prepare a photoreceptor. This photoreceptor is referred to as a photoreceptor Y7.

Example 6 (photoreceptor Y8)
In the same manner as in Example 5, a photoconductor prepared using a mixture of B1 and B2 (mass ratio 8/2) (average COOH value 155 μeq / g) instead of resin B1 is referred to as photoconductor Y8. .
Comparative Example 6 (Photoconductor Y9)
In the same manner as in Example 5, a photoconductor Y9 was prepared by using a mixed product of resin B1 and B2 (mass ratio 2/8) (average COOH value 48 μeq / g) instead of resin B1. .

Comparative Example 7 (Photoconductor Y10)
In the same manner as in Example 5, a photoconductor prepared using resin B2 (COOH value 12 μeq / g) instead of resin B1 is referred to as photoconductor Y10.
Using these four Y7 to 10 photoconductors, an adhesion test was carried out in the same manner as described above. The results are shown in Table-5.

Example 7 (photoreceptor Y11)
The following charge generation layer and charge transport layer were formed on an aluminum plate having a thickness of 0.5 mm to prepare a photoreceptor for adhesion test. As a charge generation material, CuKα characteristic X shown in FIG. 2 (D type) 20 parts of titanium oxyphthalocyanine having a powder X-ray diffraction spectrum pattern with respect to X-rays and 280 parts of 1,2-dimethoxyethane were mixed and pulverized with a sand grind mill for 2 hours for atomization dispersion treatment. Subsequently, 600 parts of a 4% 1,2-dimethoxyethane solution of polyvinyl butyral and 300 parts of 1,2-dimethoxyethane were mixed to prepare a dispersion. This dispersion was applied onto the aluminum plate with a bar coater to form a charge generation layer so that the film thickness after drying was 0.4 μm.

Next, 50 parts of the mixture (CTM-1) used in Example 1 as a charge transport material, 100 parts of resin C1 (COOH value 192 μeq / g), and 0.05 part of silicone oil as a leveling agent were added in tetrahydrofuran. A solution dissolved in 640 parts of toluene / toluene (8/2) mixed solvent is applied thereon, dried at 125 ° C. for 20 minutes, and provided with a charge transport layer so that the film thickness after drying is 25 μm. Produced. This photoreceptor is referred to as a photoreceptor Y11.

Comparative Example 8 (Photoconductor Y12)
A photoconductor prepared using resin C2 (COOH value 46 μeq / g) instead of resin C1 in the same manner as in Example 7 is used as photoconductor Y12. Using these two photoconductors Y11 and Y12, the photoconductor is described above. The adhesion test was carried out in the same manner as above. The results are shown in Table-6.

<Manufacture of photosensitive drum>
Example 8
The coating solution for forming the undercoat layer, the coating solution for the charge generation layer and the charge used in Example 1 were placed on an aluminum cylinder having a mirror-finished outer diameter of 30 mm, a length of 260.5 mm, and a wall thickness of 0.75 mm. The coating solution for the transport layer is sequentially applied by the dip coating method, and the undercoat layer, the charge generation layer, and the charge transport layer are formed so that the film thicknesses after drying are 1.5 μm, 0.4 μm, and 21 μm, respectively. As a result, a photosensitive drum Z1 was obtained.

  Using this photosensitive drum Z1, an image characteristic test was conducted. The image characteristic test was performed using a color printer HP Color LaserJet 4650dn (cleaning blade, counter contact method) manufactured by Hewlett-Packard Company. The produced photosensitive drum Z1 and toner were mounted on a cyan process cartridge, and this cartridge was mounted on a printer. When an image was formed under an environment of a temperature of 25 ° C. and a humidity of 50% and the obtained image was visually confirmed, a good image was obtained. Further, the first and 1000th images were visually confirmed, but no change was observed.

1 Photoconductor (Electrophotographic photoconductor)
2 Charging device (charging roller; charging unit)
3 Exposure equipment (exposure section)
4 Development device (development unit)
5 Transfer device 6 Cleaning device (cleaning part)
7 Fixing Device 41 Developing Tank 42 Agitator 43 Supply Roller 44 Developing Roller 45 Regulating Member 71 Upper Fixing Member (Pressure Roller)
72 Lower fixing member (fixing roller)
73 Heating device T Toner P Recording paper (paper, medium)

Claims (5)

In an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, the photosensitive layer contains a polyarylate resin having a carboxylic acid terminal value of 100 μ equivalent / g or more and 500 μ equivalent / g or less and a triphenylamine compound. The polyarylate resin is represented by the following formula (1).
An electrophotographic photosensitive member characterized by have a structural unit.

(In the formula (1), Ar ^{1 to} Ar ⁴ may each independently have an arylene.
Represents a group, and X represents a single bond, an oxygen atom, a sulfur atom, or an alkylene group. s is 0 or more and 2 or less
Represents the lower integer. Y represents a single bond, an oxygen atom, a sulfur atom, or an alkylene group. ) The electrophotographic photoreceptor according to claim 1, wherein the carboxylic acid terminal value is 150 μ equivalent / g or more and 500 μ equivalent / g or less. The electrophotographic photosensitive member according to claim 1 or 2 viscosity average molecular weight Mv of the polyarylate resin is characterized by a 10,000 to 200,000. The process cartridge for an electrophotographic photosensitive member according to any one of claims 1 to 3, characterized in that it comprises a charging means for charging the electrophotographic photosensitive member. The electrophotographic photosensitive member according to any one of claims 1 to 3 , charging means for charging the electrophotographic photosensitive member, and exposing the charged electrophotographic photosensitive member to form an electrostatic latent image. An image forming apparatus comprising: an exposure unit; a developing unit that develops the electrostatic latent image with toner; and a transfer unit that transfers the toner to a transfer target.

Images