JP2011095663A - Method for manufacturing electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing electrophotographic photoreceptors which reduces the variation in thicknesses of intermediate layers or difference in thicknesses of intermediate layers among electrophotographic photoreceptors and are excellent in image quality. <P>SOLUTION: In the method for manufacturing electrophotographic photoreceptors, (T1-T2) is 3 to 20°C when T1 (°C) is the temperature of a support when applying an intermediate layer coating liquid onto the support and T2 (°C) is the temperature of the intermediate layer coating liquid when applying the intermediate layer coating liquid onto the support. The intermediate layer coating liquid contains resin particles and has total solid concentration of ≥10 mass% and has viscosity at 23°C and 1 atm pressure, of 2.0 to 20.0 cp. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing an electrophotographic photoreceptor.

The electrophotographic photosensitive member is required to have high image quality without sensitivity, electrical characteristics, optical characteristics, and image defects according to the applied electrophotographic process.
Among them, an intermediate layer (sometimes called an undercoat layer) of the electrophotographic photosensitive member is electrically blocked so that charge injection does not occur from the support of the electrophotographic photosensitive member when a voltage is applied to the electrophotographic photosensitive member. Function is required. This is because when charge is injected from the support, the charging ability is lowered, the image contrast is lowered, and in the case of the reversal development method, black spots and background fogging are caused on the white background described above, and the image quality is lowered.

  On the other hand, if the intermediate layer is made too thick so as not to cause charge injection from the support, the charge generated in the photosensitive layer of the electrophotographic photosensitive member stays inside the photosensitive layer, resulting in an increase in residual potential. Or potential fluctuation due to repeated use. Therefore, it is necessary to reduce the thickness of the intermediate layer to some extent while providing an electrical blocking function. Therefore, in order to avoid the increase in the residual potential even when the intermediate layer is thick to some extent, there is a method for reducing the accumulation of charges inside the electrophotographic photosensitive member by including a metal oxide in the intermediate layer. .

Examples of the resin used for the intermediate layer include thermosetting resins such as polyamide resin, vinyl chloride resin, vinyl acetate resin, polyvinyl acetal resin, polyvinyl butyral resin, polyvinyl alcohol resin, melamine resin, epoxy resin, and alkyd resin. . Patent Document 1 discloses a configuration in which TiO ₂ and polyamide resin are contained in an intermediate layer.

In addition, Patent Document 2 discloses a configuration in which a layer formed of a polyolefin resin having excellent dielectric properties is provided on a support. Patent Document 3 discloses a configuration in which a conductive layer containing SnO ₂ doped with antimony and a polyester ionomer is provided on a support.

  In recent years, the performance required for electrophotographic photoreceptors has been increasing, and due to the effect on image quality, the uniformity of the thickness of each layer constituting the electrophotographic photoreceptor is required to be extremely high. In particular, in the intermediate layer, although the film thickness is generally small, the film thickness greatly affects the black spot, the ground fogging, and the potential fluctuation as described above.

  Similarly, in recent years, the tact time of each process in the production of an electrophotographic photosensitive member has been shortened from the viewpoint of mass production of the electrophotographic photosensitive member. The time from cleaning / drying of the support to application of the coating solution for the intermediate layer is also shortened, and the support after drying may not be sufficiently cooled. At that time, temperature variation between one support and temperature variation between supports when a large number of coatings are applied simultaneously are likely to occur, and the uniformity of the film thickness of the intermediate layer cannot be maintained due to the variation. . As a result, problems such as partial black spots, background fog, image density fluctuations, and image density differences between electrophotographic photosensitive members may occur.

JP 2002-229237 A Japanese Laid-Open Patent Publication No. 01-114853 JP 2000-231178 A

  It is an object of the present invention to provide an electrophotographic photosensitive member having excellent image quality with little variation in the thickness of the intermediate layer and a difference in the thickness of the intermediate layer between the electrophotographic photosensitive members even in the manufacturing process of the electrophotographic photosensitive member having a short tact time. It is in providing the manufacturing method of a body.

The present invention provides the following method for producing an electrophotographic photoreceptor.
Applying an intermediate layer coating solution on a support to form an intermediate layer; and
In the method for producing an electrophotographic photosensitive member having a step of forming a photosensitive layer by applying a photosensitive layer coating solution on the formed intermediate layer,
The temperature of the support when applying the intermediate layer coating solution on the support is T1 (° C.), and the temperature of the intermediate layer coating solution when applying the intermediate layer coating solution on the support is When T2 (° C), (T1-T2) is 3 ° C or higher and 20 ° C or lower,
The intermediate layer coating solution contains resin particles,
The total solid concentration in the intermediate layer coating solution is 10% by mass or more,
A method for producing an electrophotographic photosensitive member, wherein the viscosity of the intermediate layer coating solution measured at a temperature of 23 ° C./1 atm is 2.0 cp to 20.0 cp.

  According to the manufacturing method of the present invention, the uniformity of the film thickness of the intermediate layer between the electrophotographic photosensitive member and the electrophotographic photosensitive member is maintained for a long time in the manufacturing process. Therefore, it is possible to provide a method for producing an electrophotographic photosensitive member capable of forming excellent image quality without image defects and image density differences in image formation using the obtained electrophotographic photosensitive member.

1 shows an example of a schematic configuration of a process cartridge equipped with the electrophotographic photosensitive member of the present invention and an electrophotographic apparatus including the process cartridge. FIG. 2 is a diagram schematically illustrating an example of a layer configuration of the electrophotographic photosensitive member of the present invention.

  The electrophotographic photosensitive member in the present invention is obtained by forming an intermediate layer and a photosensitive layer in this order on a support.

  Even if the photosensitive layer is a single-layer type photosensitive layer containing the charge transport material and the charge generation material in the same layer, the charge generation layer containing the charge generation material and the charge transport layer containing the charge transport material Separated layered (functionally separated type) photosensitive layers may be used. In the present invention, a laminated photosensitive layer is preferred from the viewpoint of electrophotographic characteristics. The laminated photosensitive layer has a normal layer type photosensitive layer laminated in the order of the charge generation layer and the charge transport layer from the support side, and a reverse layer type photosensitive layer laminated in the order of the charge transport layer and the charge generation layer from the support side. However, a normal photosensitive layer is preferred from the viewpoint of electrophotographic characteristics.

  Further, a conductive layer containing a metal oxide may be provided between the intermediate layer and the support. An outline of a preferred structure of the electrophotographic photosensitive member in the present invention is shown in FIG. In the electrophotographic photosensitive member of FIG. 2, a conductive layer 22, an intermediate layer 23, a charge generation layer 24, and a charge transport layer 25 are laminated on a support 21.

The support used in the electrophotographic photoreceptor of the present invention may be conductive (conductive support), for example, a support made of metal (alloy) such as aluminum, aluminum alloy, and stainless steel. Can be used. Moreover, the said metal support body and plastic support body which have the layer which carried out the film formation of the metal or alloys, such as aluminum, an aluminum alloy, an indium oxide tin oxide alloy, by vacuum deposition can also be used. Also, a support in which conductive particles such as carbon black, tin oxide particles, titanium oxide particles, and silver particles are impregnated into plastic or paper together with an appropriate binder resin, or a plastic support having a conductive binder resin Can also be used. Examples of the shape of the support include a cylindrical shape and a belt shape, and a cylindrical shape is preferable.

  The support is often made of an oil-based substance such as cutting oil during processing, and human fingerprints may adhere to the support when it is transported. Therefore, it is necessary to sufficiently wash the support when producing the electrophotographic photosensitive member.

  As a method for washing the support, there is a method in which the surface of the support is cleaned by dipping in pure water and then pulled up and then dried. As a preferable method employed in the cleaning step, ultrasonic cleaning can be exemplified. When the support is immersed in the pure water immersion tank, it is preferable to take an immersion time (a time during which the support is stopped in the tank) in the tank. The time is preferably 10 to 60 seconds, although depending on the support to be immersed. That is, it is preferable to take time for the temperature of the support to rise to the temperature of pure water in the tank. Further, the temperature of pure water used is preferably higher in order to remove impurities on the support, and when the support and the temperature of pure water are raised from the pure water immersion tank, the support is dried. It's easy to do. Therefore, it is preferable to immerse in warm water having a temperature of 80 ° C. or higher at the end of the cleaning process.

The method for producing an electrophotographic photosensitive member of the present invention includes a step of applying an intermediate layer coating solution on a support to form an intermediate layer.
In the above step of the present invention, the temperature of the support when applying the intermediate layer coating solution on the support is T1 (° C.), and the intermediate layer coating when applying the intermediate layer coating solution on the support When the temperature of the coating solution is T2 (° C.), (T1-T2) is 3 ° C. or more and 20 ° C. or less, the coating solution for intermediate layer contains resin particles, and the total solid in the coating solution for intermediate layer The partial concentration is 10% by mass or more, and the viscosity of the intermediate layer coating solution measured at a temperature of 23 ° C./1 atm is 2.0 cp to 20.0 cp.

  The inventors of the present invention have repeatedly studied to maintain the uniformity of the film thickness of the intermediate layer when forming the intermediate layer on the support, and the temperature of the support and the coating liquid when applying the intermediate layer coating liquid. It was found that an intermediate layer having a uniform film thickness can be formed by controlling the difference, the total solid content concentration in the intermediate layer coating solution, and the viscosity of the intermediate layer coating solution.

  When the above (T1-T2) exceeds 20 ° C., the temperature difference between the intermediate layer and the support is too large, and a good film cannot be obtained during coating. On the other hand, when (T1-T2) is less than 3 ° C., drying during the support washing step is insufficient, and uneven washing of the support may occur, and a good film may not be obtained. The value of (T1-T2) is preferably 3 ° C. or higher and 10 ° C. or lower because the effects of the present invention are further exhibited. The temperature of the support was measured by measuring the surface temperature of the support. When a conductive layer to be described later was formed on the support, the temperature on the conductive layer was measured and designated as T1.

Moreover, when the total solid content concentration in the coating liquid for intermediate layer containing the resin particles is less than 10% by mass, a film thickness difference due to liquid dripping at the time of coating may occur, and image defects may be caused. In the present invention, the total solid content concentration is 10% by mass or more, but preferably 12% by mass or more. On the other hand, the upper limit of the total solid content concentration is not particularly limited as long as it is a concentration that can be used as a coating solution for an intermediate layer, but is preferably 30% by mass or less.
In addition, the total solid content concentration in the coating solution for the intermediate layer is obtained by taking an appropriate amount of the coating solution in a container and at a temperature of 14
The weight change after drying at 0 ° C. for 30 minutes was calculated.

  Further, when the viscosity of the intermediate layer coating solution measured at a temperature of 23 ° C./1 atm is less than 2 cp or more than 20 cp, uneven coating due to sagging during coating of the intermediate layer coating solution may occur, or electrophotographic photosensitive An image defect may be caused by an increase in film thickness variation when the body is continuously manufactured. The viscosity of the intermediate layer coating solution is preferably 4 cp or more and 10 cp or less because an intermediate layer having a more uniform film thickness can be formed. The viscosity was measured using a B-type viscometer BL type manufactured by Toki Sangyo Co., Ltd. The viscosity of the coating solution increases as the total solid content increases, but the amount of solvent is adjusted by using an aqueous dispersion containing resin particles having a particle size of 0.05 μm or more and 0.50 μm or less. By doing this, a coating solution for an intermediate layer satisfying the above-mentioned total solid content concentration and viscosity can be prepared.

  Further, the intermediate layer coating solution used in the present invention is an aqueous dispersion containing resin particles having a volume average particle size of 0.05 μm or more and 0.50 μm or less measured using a light scattering particle size distribution meter. preferable. As described above, by using an aqueous dispersion containing resin particles having such an average particle size as the intermediate layer coating solution, a coating solution satisfying both the total solid content concentration and the viscosity can be prepared. . Moreover, it is still more preferable in it being 0.1 to 0.40 μm. The average particle diameter of the resin particles can be adjusted to the above range by changing the type of solvent used for preparing the aqueous dispersion and the stirring time.

  The aqueous dispersion is a solution in which resin particles are dispersed or dissolved in an aqueous medium. Here, the aqueous medium is a medium composed of a liquid containing water as a main component, and may contain a water-soluble organic solvent. The above-mentioned main component of water means a component having the largest content in the medium contained in the solution. In the present invention, when the content ratio of water in the aqueous medium is 4% by mass or more, it is preferable because the aqueous dispersion exists more stably. More preferably, it is 30% by mass or more, and further preferably 50% by mass or more. Moreover, an upper limit in particular is not restrict | limited, Even if it is 100 mass% of water, there exists an effect of this invention.

  The resin used in the intermediate layer coating solution of the present invention is preferably present in the coating solution as resin particles having a particle size in a specific range as described above. As the resin particles, polyolefin resin particles such as polyethylene resin particles can be suitably used.

Further, the polyolefin resin has the following (A1), (A2) and (A3), and the mass ratio of (A1), (A2) and (A3) of the polyolefin resin is the following formulas (1) and ( It is preferable to satisfy 2).
0.01 ≦ (A2) / {(A1) + (A2) + (A3)} × 100 ≦ 10 Formula (1)
(A1) / (A3) = 55/45 to 99/1 Formula (2)

（式（１１）中、Ｒ^１１〜Ｒ^１４は、それぞれ独立に、水素原子、アルキル基を示す。）

（Ａ２）：下記式（２１）または（２２）で示される繰り返し構造単位

（式（２１）および（２２）中、Ｒ^２１〜Ｒ^２４は、それぞれ独立に、水素原子、アルキル基、フェニル基または−Ｙ^２１ＣＯＯＨ（式中、Ｙ^２１は、単結合、アルキレン基またはアリーレン基を示す。）で示される１価の基を示し、Ｒ^２５およびＲ^２６は、それぞれ独立に、水素原子、アルキル基またはフェニル基を示し、Ｘ^２１は、−Ｙ^２２ＣＯＯＣＯＹ^２３−（式中、Ｙ^２２およびＹ^２３は、それぞれ独立に、単結合、アルキレン基またはアリーレン基を示す。）で示される２価の基を示す。ただし、Ｒ^２１〜Ｒ^２４のうち少なくとも１つは−Ｙ^２１ＣＯＯＨで示される１価の基である。）

（Ａ３）：下記式（３１）、（３２）、（３３）または（３４）で示される繰り返し構造単位

（式（３１）〜（３４）中、Ｒ^３１〜Ｒ^３５は、それぞれ独立に、水素原子またはメチル基を示し、Ｒ^４１〜Ｒ^４３は、それぞれ独立に、炭素数１〜１０のアルキル基を示し、Ｒ^５１〜Ｒ^５３は、それぞれ独立に、水素原子または炭素数１〜１０のアルキル基を示す。） (A1): Repeating structural unit represented by the following formula (11)

(In formula (11), R ^{11 to} R ¹⁴ each independently represent a hydrogen atom or an alkyl group.)

(A2): Repeating structural unit represented by the following formula (21) or (22)

(In the formulas (21) and (22), R ^{21 to} R ²⁴ are each independently a hydrogen atom, an alkyl group, a phenyl group or —Y ²¹ COOH (wherein Y ²¹ is a single bond, an alkylene group or an arylene) R ²⁵ and R ²⁶ each independently represents a hydrogen atom, an alkyl group or a phenyl group, and X ²¹ represents —Y ²² COOCOY ²³ — (in the formula: , Y ²² and Y ²³ each independently represents a single bond, an alkylene group or an arylene group.) However, at least one of R ^{21 to} R ²⁴ is —Y ^21. (It is a monovalent group represented by COOH.)

(A3): repeating structural unit represented by the following formula (31), (32), (33) or (34)

(In formulas (31) to (34), R ^{31 to} R ³⁵ each independently represent a hydrogen atom or a methyl group, and R ^{41 to} R ⁴³ each independently represents an alkyl group having 1 to 10 carbon atoms. R ^{51 to} R ⁵³ each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)

When a polyolefin resin that satisfies the above requirements is used, it is preferable because it is possible to prepare a coating solution that satisfies the above-mentioned total solid content concentration and viscosity and that has a high stability of the coating solution. More preferably, the following formula is further satisfied.
0.01 ≦ (A2) / {(A1) + (A2) + (A3)} × 100 ≦ 5

The monomer for constituting (A2) contained in the polyolefin resin is a compound having at least one of a carboxylic acid group and a carboxylic anhydride group, and at least one of the carboxylic acid group and the carboxylic anhydride group is Within the compound molecule (in the monomer unit).

  As the compound having at least one of the carboxylic acid group and the carboxylic acid anhydride group, an unsaturated carboxylic acid or an anhydride thereof is preferable. Specific examples include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid and crotonic acid, as well as unsaturated dicarboxylic acid half esters and half amides. Among these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable.

  Moreover, (A2) comprised from the compound which has at least one of the said carboxylic acid group and carboxylic anhydride group is contained as a repeating structural unit in polyolefin resin which is a copolymer. Moreover, the form of the said copolymer is not specifically limited, A random copolymer, a block copolymer, and a graft copolymer are mentioned.

In general formula (21) of (A2) above, the alkyl group and the alkylene group preferably have 1 to 7 carbon atoms.
Further, three of R ^{21 to} R ²⁴ are hydrogen atoms, one is —COOH, or two of R ^{21 to} R ²⁴ are hydrogen atoms, one is a methyl group, and one is —COOH. Is more preferable. In the general formula (22) of (A2), R ²⁵ and R ²⁶ are more preferably hydrogen, and X ²¹ is more preferably —COOCO—.

  The unsaturated carboxylic acid anhydride such as maleic anhydride forms an acid anhydride structure in which the adjacent carboxyl groups are dehydrated and cyclized in the dry state of the resin. However, for example, in an aqueous medium containing a basic compound, part or all of the ring is opened, and the structure of a carboxylic acid or a salt thereof is easily formed. In the present invention, when the amount of the compound having a carboxylic acid group or a carboxylic acid anhydride group is defined based on the amount of the carboxyl group of the resin, all the carboxylic acid anhydride groups in the resin are ring-opened. It is calculated assuming that it is based.

  In the present invention, examples of the monomer for constituting (A1) contained in the polyolefin resin include ethylene, propylene, isobutylene, 1-butene, 1-pentene, and 1-hexene. These can be used alone or as a mixture. Among these, alkenes having 2 to 4 carbon atoms such as ethylene, propylene, isobutylene, and 1-butene are more preferable, and ethylene is particularly preferable.

In general formula (11) of (A1) above, R ^{11 to} R ¹⁴ are preferably each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ^{11 to} R ¹⁴ are all hydrogen. Preferably there is.

Moreover, in this invention, as a monomer for comprising (A3) contained in the said polyolefin resin, the following compound is mentioned, for example.
Repeating structural units represented by the above formula (31): (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate.
The repeating structural unit represented by the above formula (32): maleic acid esters such as dimethyl maleate, diethyl maleate and dibutyl maleate.
A repeating structural unit represented by the above formula (33): (meth) acrylic acid amides.
Repeating structural unit represented by the above formula (34): vinyl alcohol obtained by saponifying alkyl vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, and vinyl esters with a basic compound.

These compounds can be used alone or as a mixture. Among these, (meth) acrylic acid esters are more preferable, and methyl (meth) acrylate and ethyl (meth) acrylate are particularly preferable. That is, (A3) is preferably a repeating structural unit represented by the above formula (31), and R ⁴¹ in the above formula (31) is more preferably methyl or ethyl.

  In the present invention, the polyolefin resin is particularly preferably a terpolymer synthesized from ethylene, methyl (meth) acrylate or ethyl (meth) acrylate, and maleic anhydride. Specific examples of the terpolymer include ethylene-acrylic acid ester-maleic anhydride terpolymer or ethylene-methacrylic acid ester-maleic anhydride terpolymer.

The acrylic ester unit may be converted to an acrylic acid unit by hydrolyzing a small part of the ester bond when the resin is made aqueous. In such a case, the change is taken into account. It suffices if the ratio of each structural unit is within a specified range. The polyolefin resin used in the present invention is measured by the following method.
(1) Content of (A2) (unsaturated carboxylic acid component) in polyolefin resin The acid value of polyolefin resin was measured according to JIS K5407, and the content (graft rate) of unsaturated carboxylic acid was determined from the value. Obtained from the formula.
Content of unsaturated carboxylic acid component (mass%) = (mass of grafted unsaturated carboxylic acid) / (mass of raw material polyolefin resin) × 100
(2) Composition of resin other than (A2) in polyolefin resin ¹ H-NMR, ¹³ C-NMR analysis at 300 ° C. in orthodichlorobenzene (d4) (manufactured by Varian Technologies Japan Limited, 300 MHz) ). ^{In 13} C-NMR analysis, measurement was performed using a gated decoupling method in consideration of quantitativeness.

  The polyolefin resin used in the present invention may contain other components other than those described above as repeating structural units of the copolymer to the extent that the effects of the present invention are not impaired. Examples of the monomer for constituting another repeating structural unit include dienes, (meth) acrylonitrile, halogenated vinyls, halogenated vinylidenes, carbon monoxide, and carbon disulfide.

  Although the molecular weight of the polyolefin resin used for this invention is not specifically limited, The thing of 10,000-50,000 is used suitably. Further, the synthesis method is not particularly limited. The above polyolefin resins are described in Chapters 1 to 4 (Kyoritsu Shuppan Co., Ltd.), Japanese Patent Application Laid-Open No. 2003-105145, and Japanese Patent Application Laid-Open No. 2003-147028. Can be synthesized using known methods described in 1. For example, a monomer for constituting the polyolefin resin can be obtained by high-pressure radical copolymerization in the presence of a radical generator.

The intermediate layer coating solution of the present invention can be prepared, for example, by dissolving resin particles such as a polyolefin resin in an appropriate solvent, by keeping the polyolefin resin in a molten state by maintaining it at a high temperature above the softening point. It is prepared by a method of producing and a method of heating and stirring in an appropriate solvent to form a dispersion.
The intermediate layer can be formed by applying an intermediate layer coating solution on a support. The content of the resin particles in the intermediate layer is preferably 5 to 30% by mass with respect to the total solid content of the intermediate layer. The film thickness of the intermediate layer is preferably 0.05 to 10 μm, and more preferably 0.3 to 5 μm.
In addition, the coating liquid for intermediate | middle layers of this invention can also be made to contain another component in the range which does not impair the effect of this invention. Examples of other components include metal oxides and organic particles.

  In the electrophotographic photoreceptor of the present invention, a conductive layer containing conductive particles may be separately provided between the support and the intermediate layer for the purpose of concealing defects on the support and suppressing moire. As the resin used for the conductive layer, it is preferable to use a thermosetting resin such as a phenol resin or a polyurethane resin. For example, zinc oxide, titanium oxide, or barium sulfate is used as the conductive particles. The conductive layer can be formed by preparing a coating liquid for a conductive layer by dissolving or dispersing the resin and conductive particles in an appropriate solvent, and coating the coating liquid for the conductive layer on a support. it can. The thickness of the conductive layer is preferably 10 to 35 μm.

  When the conductive layer coating liquid containing the thermosetting resin and conductive particles is applied on the support and then dried, it is preferably dried at a high temperature of 130 ° C. or higher. In addition, a surface roughening material for roughening the surface of the conductive layer is provided on the conductive layer in order to suppress interference fringes in the output image due to interference of the light reflected on the surface of the conductive layer. It is also possible to add. As the surface roughening material, resin particles having an average particle diameter of 1 to 6 μm are preferable. Examples of the resin particles include curable resin particles such as curable rubber, polyurethane resin, epoxy resin, alkyd resin, phenol resin, polyester resin, silicone resin, and acrylic-melamine resin. Among these, silicone resin particles that are difficult to aggregate are preferable. Moreover, in order to improve the surface property of a conductive layer, you may add a well-known leveling agent.

  The method for producing an electrophotographic photoreceptor of the present invention includes a step of forming a photosensitive layer by applying a photosensitive layer coating solution on the formed intermediate layer. As described above, the photosensitive layer is preferably a stacked type (functional separation type) photosensitive layer separated into a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material. The charge generation layer suitably used for the electrophotographic photosensitive member of the present invention contains a binder resin and a charge generation material. Examples of the charge generating substance include azo pigments such as monoazo, disazo, and trisazo, phthalocyanine pigments such as metal phthalocyanine and nonmetal phthalocyanine, indigo pigments such as indigo and thioindigo, perylene acid anhydride, and perylene acid. Perylene pigments such as imide, polycyclic quinone pigments such as anthraquinone, pyrenequinone and dibenzpyrenequinone, squarylium dyes, pyrylium and thiapyrylium salts, triphenylmethane dyes, selenium, selenium-tellurium, amorphous Inorganic substances such as silicon, quinacridone pigments, azulenium salt pigments, cyanine dyes such as quinocyanine, anthanthrone pigments, pyranthrone pigments, xanthene dyes, quinoneimine dyes, styryl dyes, cadmium sulfide And arm, zinc oxide, and the like. These charge generation materials may be used alone or in combination of two or more.

  Examples of the binder resin used for the charge generation layer include acrylic resin, allyl resin, alkyd resin, epoxy resin, diallyl phthalate resin, silicone resin, styrene-butadiene copolymer, phenol resin, butyral resin, benzal resin, polyacrylate resin. , Polyacetal resin, polyamideimide resin, polyamide resin, polyallyl ether resin, polyarylate resin, polyimide resin, polyurethane resin, polyester resin, polyethylene resin, polycarbonate resin, polystyrene resin, polysulfone resin, polyvinyl acetal resin, polybutadiene resin, polypropylene resin Methacrylic resin, urea resin, vinyl chloride-vinyl acetate copolymer, vinyl acetate resin, and vinyl chloride resin. Among these, a butyral resin is particularly preferable. These may be used alone or in combination as a mixture or copolymer.

The charge generation layer can be formed by applying a charge generation layer coating solution obtained by dispersing a charge generation material together with a binder resin and a solvent and drying the coating solution. Examples of the dispersion method include a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill,
Examples include a method using a vibration mill, an attritor, and a liquid collision type high-speed disperser. The ratio between the charge generating material and the binder resin is preferably in the range of 1: 0.3 to 1: 4 (mass ratio).

  The solvent used in the coating solution for the charge generation layer is selected from the binder resin used and the solubility and dispersion stability of the charge generation material. Examples of the organic solvent include alcohols, sulfoxides, ketones, ethers and esters. , Aliphatic halogenated hydrocarbons and aromatic compounds.

The thickness of the charge generation layer is preferably 5 μm or less, and more preferably 0.1 to 2 μm.
In addition, various sensitizers, antioxidants, ultraviolet absorbers, and plasticizers can be added to the charge generation layer as necessary.

  The charge transport layer suitably used for the electrophotographic photoreceptor of the present invention contains a charge transport material and a binder resin. The charge transport layer can be formed by applying a charge transport layer coating solution obtained by dissolving a film-forming binder resin and a charge transport material in a solvent, and drying it. The charge transport material may be used alone or in combination of two or more.

Examples of the charge transport material include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triallylmethane compounds, and thiazole compounds. These charge transport materials may be used alone or in combination of two or more.
Examples of the binder resin used for the charge transport layer include polyester, polycarbonate, polymethacrylic acid ester, polyarylate, polysulfone, and polystyrene. These may be used alone or in combination as a mixture or copolymer.
The thickness of the charge transport layer is preferably 5 to 40 μm, and more preferably 10 to 35 μm.

  In addition, an antioxidant, an ultraviolet absorber, and a plasticizer can be added to the charge transport layer as necessary. Further, a fluorine atom-containing resin or a silicone-containing resin may be contained. Moreover, you may contain the particle | grains comprised with the said resin. Moreover, you may contain a metal oxide particle and an inorganic particle. However, when the charge transport layer is used as the surface layer of the electrophotographic photosensitive member, it can be contained in a range that does not affect the position of the charged column.

  When applying the coating liquid for each of the above layers, for example, an application method such as dip coating (dip coating), spray coating, spinner coating, roller coating, Meyer bar coating, or blade coating is used. be able to.

  FIG. 1 shows an example of a schematic configuration of an electrophotographic apparatus having a process cartridge provided with the electrophotographic photosensitive member of the present invention.

In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member, which is driven to rotate about a shaft 2 in a direction indicated by an arrow at a predetermined peripheral speed.
The peripheral surface (surface) of the electrophotographic photosensitive member 1 that is driven to rotate is uniformly charged to a predetermined negative potential by the charging unit 3, and then exposure unit (not shown) such as slit exposure or laser beam scanning exposure. The exposure light (image exposure light) 4 output from is received. In this way, electrostatic latent images corresponding to the target image are sequentially formed on the peripheral surface of the electrophotographic photosensitive member 1. The voltage applied to the charging means 3 may be either a voltage obtained by superimposing an alternating current component on a direct current component or a voltage containing only a direct current component. In the embodiment, a charging means that applies only a direct current component is used.

  The electrostatic latent image formed on the peripheral surface of the electrophotographic photosensitive member 1 is developed with toner of the developing unit 5 to become a toner image. Next, the toner images formed and supported on the peripheral surface of the electrophotographic photosensitive member 1 are sequentially transferred by the transfer bias from the transfer unit 6. The transfer material P is taken out from a transfer material supply means (not shown) between the electrophotographic photoreceptor 1 and the transfer means 6 (contact portion) in synchronization with the rotation of the electrophotographic photoreceptor 1 and fed. .

The transfer material P that has received the transfer of the toner image is separated from the peripheral surface of the electrophotographic photosensitive member 1 and is introduced into the fixing means 8 to undergo image fixing, and is printed out of the apparatus as an image formed product (print, copy). Be out.
The peripheral surface of the electrophotographic photosensitive member 1 after the transfer of the toner image is cleaned by the developer 7 after the transfer residual developer (toner) is removed by the cleaning unit 7, and the pre-exposure light from the pre-exposure unit (not shown) 11 is used for repeated image formation.
As the transfer means, for example, an intermediate transfer type transfer means using a belt-like or drum-like intermediate transfer member may be employed.

  In FIG. 1, an electrophotographic photosensitive member 1, a charging means (contact charging means) 3, a developing means 5 and a cleaning means 7 are integrally supported to form a cartridge, and guide means 10 such as a rail of an electrophotographic apparatus main body. The process cartridge 9 is detachable from the main body of the electrophotographic apparatus.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. The following “parts” means “parts by mass”.
(Production Example 1: Polyolefin resin PO-1)
Using a stirrer equipped with a heat-resistant 1-liter glass container with a heater, 75 parts of polyolefin resin (trade name: Bondine HX-8290, manufactured by Sumitomo Chemical Co., Ltd.), 90 parts of isopropanol, in the resin 1.2 times equivalent of triethylamine with respect to the carboxyl group of maleic anhydride and 200 parts of distilled water were charged in a glass container and stirred at a rotation speed of the stirring blade of 300 rpm. No sedimentation was observed, and it was confirmed that the product was floating. Therefore, while maintaining this state, the heater was turned on and heated after 15 minutes. Then, the system temperature was maintained at 145 ° C., and further stirred for 60 minutes. Then, after putting in a water bath and cooling to room temperature (about 25 ° C.) while stirring at a rotational speed of 300 rpm, pressure filtration (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) Thus, a milky white uniform aqueous polyolefin resin dispersion (polyolefin resin PO-1) having a total solid content of 20% by mass was obtained.
This polyolefin resin PO-1 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, and (A3) obtained by copolymerizing ethyl acrylate. (A1) / (A2) / (A3) = 91.00 / 3.00 / 6.00 (mass%).
The characteristics of the resin were measured or evaluated by the following method.
(1) Content of (A2) (unsaturated carboxylic acid component) in polyolefin resin The acid value of polyolefin resin was measured according to JIS K5407, and the content (graft rate) of unsaturated carboxylic acid was determined from the value. Obtained from the formula.
Content of unsaturated carboxylic acid component (mass%) = (mass of grafted unsaturated carboxylic acid) / (mass of raw material polyolefin resin) × 100
(2) Composition of resin other than (A2) in polyolefin resin ¹ H-NMR, ¹³ C-NMR analysis at 120 ° C. in orthodichlorobenzene (d4) (manufactured by Varian Technologies Japan Limited, 300 MHz) Asked to go. ^{In 13} C-NMR analysis, measurement was performed using a gated decoupling method in consideration of quantitativeness.
The method for synthesizing the polyolefin resin is not limited to Production Example 1. Chapters 1 to 4 (Kyoritsu Shuppan Co., Ltd.) of “New Polymer Experiment 2 Polymer Synthesis / Reaction (1)”, JP 2003-105145 A And a known method described in JP-A No. 2003-147028.

Example 1
An aluminum cylinder (JIS-A3003, aluminum alloy) having a length of 260.5 mm and a diameter of 30 mm manufactured by the extrusion / pulling-out process was prepared as a support for the electrophotographic photosensitive member. Next, the support was washed. First, the cylinder was placed vertically in the washing tank, and ultrasonic waves were applied for 30 seconds while stopping at that position. Next, after raising, the cylinder was put into a hot water tank (temperature 80 ° C.) and dried. At the time of washing the support and producing the electrophotographic photosensitive member, the tact time of the washing step and the coating step was 35 seconds, and in the coating step, a coating apparatus capable of performing 42 dip coatings simultaneously was used.

Next, TiO ₂ particles coated with oxygen-deficient SnO ₂ (powder resistivity 100 Ω · cm, SnO ₂ coverage (mass ratio) 35%) 80 parts, methanol 15 parts as solvent, methoxypropanol 15 parts Was dispersed in a sand mill using glass beads having a diameter of 1 mm for 3 hours to prepare a dispersion.
In this dispersion, 3.9 parts of silicone resin particles (trade name: Tospearl 120, manufactured by GE Toshiba Silicone Co., Ltd., average particle size: 2.0 μm) as a surface roughening agent, silicone oil as a leveling agent (product) Name: 0.001 part of SH28PA, manufactured by Toray Dow Corning Silicone Co., Ltd.) was added and stirred to prepare a coating solution for a conductive layer.

  On the washed support, the conductive layer coating solution was dip coated and dried at a temperature of 140 ° C. for 30 minutes to form a 30 μm conductive layer.

Next, the prepared PO-1 was prepared as a polyolefin resin used for the intermediate layer.
In addition, the particle diameter of the resin particles is the same as the solvent composition of the coating solution for intermediate layer, using a Zetasizer NanoZS light scattering particle size distribution meter (MODEL ZEN 3600) manufactured by Malvern Instrument Ltd. The volume average particle size was determined. The resin particles have a refractive index of 1.53 for the polyolefin resin, a refractive index of the measurement solvent of 1.336 for water and a refractive index of 1.375 for isopropyl alcohol. The value calculated accordingly was used.

  In a sealable pressure-resistant 1 liter glass container equipped with a stirrer, 60.0 parts polyolefin resin (PO-1), 30.0 parts ethanol, 3.9 parts N, N-dimethylethanolamine And 206.1 parts of distilled water were charged. Subsequently, when the obtained mixture was stirred at a rotational speed of the stirring blade of the stirrer at 300 rpm, no precipitation of resin particles was observed at the bottom of the container, and it was confirmed that the mixture was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 140 ° C. and further stirred for 20 minutes. Then, it put on the water bath and cooled to room temperature (temperature about 25 degreeC), stirring with a rotational speed of 300 rpm. Pressure filtration (air pressure 0.2 MPa) was performed with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain a milky white uniform aqueous polyolefin resin dispersion.

Next, 0.2 mol of stannic chloride pentahydrate was dissolved in 200 ml of water to make a 0.5 M aqueous solution, and 28% ammonia water was added with stirring to add white tin oxide having a pH of 1.5. An ultrafine particle-containing slurry was obtained. After the obtained tin oxide ultrafine particle-containing slurry is heated to a temperature of 70 ° C., it is naturally cooled to a temperature of around 50 ° C., and then pure water is added to obtain a 1 liter tin oxide ultrafine particle-containing slurry, which is then centrifuged. Solid-liquid separation was performed. 8 to this water-containing solid content
After adding 00 ml of pure water and stirring and dispersing with a homogenizer, washing was performed by solid-liquid separation using a centrifuge. 75 ml of pure water was added to the water-containing solid content after washing to prepare a tin oxide ultrafine particle-containing slurry. To the resulting slurry containing tin oxide ultrafine particles, 3.0 ml of triethylamine was added and stirred. After the transparency was raised, the temperature was raised to 70 ° C., then the heating was stopped and the whole solid content concentration was reduced by natural cooling. A tin oxide sol solution containing 20% by mass of organic amine as a dispersion stabilizer was obtained.

  Next, 100 parts of the aqueous polyolefin resin dispersion and 100 parts of the tin oxide sol solution are mixed, and IPA (isopropyl alcohol) is added and stirred so that the total solid concentration after mixing is 14% by mass. Thus, an intermediate layer coating solution was prepared. The particle size of the resin particles in the intermediate layer solvent composition was 0.10 μm, and the viscosity of the intermediate layer coating solution was 4.0 cp.

  The intermediate layer coating solution was dip coated on the conductive layer and dried at a temperature of 120 ° C. for 10 minutes to form a 1 μm intermediate layer. As a result of analyzing the composition of the polyolefin copolymer in the intermediate layer produced as described above, it was confirmed that the composition ratio was the same as that of the polyolefin resin raw material before producing the aqueous polyolefin resin dispersion. The temperature of the intermediate layer coating solution was 22 ° C. immediately before dipping in the intermediate layer coating solution, that is, immediately before the support provided with the conductive layer was lowered toward the coating solution. Moreover, the temperature of the support body provided with the conductive layer carried through the drying process after coating for the conductive layer was 29 ° C.

  Next, the Bragg angles (2θ ± 0.2 °) in CuKα characteristic X-ray diffraction are 7.5 °, 9.9 °, 16.3 °, 18.6 °, 25.1 °, and 28.3 °. 10 parts of a crystalline form of hydroxygallium phthalocyanine having a strong peak was prepared. It was mixed with 5 parts of polyvinyl butyral (trade name: ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd.) and 250 parts of cyclohexanone, and dispersed in a sand mill using glass beads having a diameter of 1 mm for 1 hour. Next, 250 parts of ethyl acetate was added to the dispersion to prepare a charge generation layer coating solution. This charge generation layer coating solution was dip-coated on the intermediate layer and dried at a temperature of 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.16 μm.

下記式（６）で示される構造を有するアミン化合物１部、

および下記式（７）で示される繰り返し構造単位を有するポリアリレート樹脂（Ｍｗ：１１０，０００）１０部、

を、最終質量比でモノクロルベンゼン：ジメトキシメタンが７：３である混合溶媒に溶解させることによって、電荷輸送用塗布液を調製した。この電荷輸送用塗布液を、浸漬塗布法で上記電荷発生層上に塗布し、これを１時間温度１２０℃で乾燥させることによって、膜厚１８μｍの電荷輸送層を形成した。 Next, 8 parts of an amine compound having a structure represented by the following formula (5),

1 part of an amine compound having a structure represented by the following formula (6):

And 10 parts of a polyarylate resin (Mw: 110,000) having a repeating structural unit represented by the following formula (7):

Was dissolved in a mixed solvent having a final mass ratio of monochlorobenzene: dimethoxymethane of 7: 3 to prepare a charge transport coating solution. The charge transport coating solution was applied onto the charge generation layer by a dip coating method and dried at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 18 μm.

  In the above procedure, a total of 1,200 electrophotographic photoreceptors having a charge transport layer as a surface layer were continuously produced with a coating apparatus capable of coating 42 simultaneously.

<Initial image evaluation and density difference evaluation>
Next, 5 of the 42 coatings initially applied in 1,200 continuous coatings were picked up at random, and the electronics manufactured by Hewlett-Packard Company under the environment of temperature 22.5 ° C. and humidity 50% RH. It was mounted on a photographic device (trade name: LaserJet 4700) and an initial image evaluation was performed. Similarly, 5 out of the last 42 of the 1,200 continuous coatings were randomly picked up and evaluated.
Specifically, the electrophotographic photosensitive member prepared above was mounted on a cyan color process cartridge and mounted on a cyan process cartridge station for evaluation. For the evaluation, a half-tone image having a 1-dot Keima pattern and a solid white image evaluation sample were output.

Ranking was performed from A to F from the sample images of five electrophotographic photosensitive members. A is a state where there is no image defect at the five evaluated and no halftone density difference. Sequentially, B, C, D and slight halftone unevenness / partial black spots appear, and ranks E, F are substantially problematic levels. In rank F, halftone unevenness and partial black spots occur in all five.
Separately, among the 1,200 continuous electrophotographic photosensitive members, the density difference between the image samples output using the first five and the last five was also confirmed. This is also set to A, B, C, and D in order from the best according to the rank of the density difference, and D is a problematic level with a significant density difference.
The results are shown in Table 2.

(Example 2)
In the preparation of the intermediate layer coating solution of Example 1, an aqueous polyolefin resin dispersion and a tin oxide sol solution were prepared and mixed, and then IPA was added so that the total solid concentration was 10% by mass and the viscosity was 2.0 cp. Then, an electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the mixed solution was diluted to prepare an intermediate layer coating solution. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 3)
In the preparation of the intermediate layer coating solution of Example 1, an aqueous polyolefin resin dispersion and a tin oxide sol solution were prepared so that the total solid concentration was 28% by mass, respectively, and then mixed in an equal amount. 0 cp. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the intermediate layer coating solution was prepared as described above. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 4
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-2. PO-2 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, and (A1). ) / (A2) / (A3) = 91.99 / 0.01 / 8.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 5)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-3. PO-3 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, (A1) ) / (A2) / (A3) = 85.00 / 5.00 / 10.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 6)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-4. PO-4 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, (A1) ) / (A2) / (A3) = 49.50 / 10.00 / 40.50 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 7)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-5. PO-5 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, and (A1). ) / (A2) / (A3) = 80.00 / 10.00 / 10.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 8)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-6. PO-6 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, and (A1). ) / (A2) / (A3) = 89.10 / 10.00 / 0.90 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 9
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-7. PO-7 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing diethyl maleate, and (A1). ) / (A2) / (A3) = 91.00 / 3.00 / 6.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 10)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-8. PO-8 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing acrylic amide, and (A1). ) / (A2) / (A3) = 91.00 / 3.00 / 6.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 11)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-9. PO-9 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing vinyl ethyl ether, (A1) ) / (A2) / (A3) = 91.00 / 3.00 / 6.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 12)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-10. PO-10 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, and (A1). ) / (A2) / (A3) = 65.00 / 30.00 / 5.00 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 13)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-11. PO-11 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, and (A1). ) / (A2) / (A3) = 48.50 / 3.00 / 48.50 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 14)
In Example 1, the polyolefin resin used for the conductive layer was changed to PO-12. PO-12 is composed of (A1) obtained by copolymerizing ethylene, (A2) obtained by copolymerizing maleic anhydride, (A3) obtained by copolymerizing ethyl acrylate, and (A1). ) / (A2) / (A3) = 96.10 / 3.00 / 0.90 (mass%). Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 15)
In the preparation of the intermediate layer coating solution of Example 1, a polyester resin was used instead of the polyolefin resin (PO-1) used in the intermediate layer, and the intermediate layer coating solution was changed to a polyester aqueous dispersion. In the same manner as above, an electrophotographic photosensitive member was produced. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Examples 16 to 19)
In the preparation of the intermediate layer coating solution of Example 1, the polyolefin resin particle size was adjusted to 0.05, 0.50, 0.03, 0 by adjusting the stirring conditions during preparation of the aqueous polyolefin resin dispersion, respectively. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the thickness was changed to 60 μm. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 1)
In the preparation of the intermediate layer coating solution of Example 1, an alcohol-soluble nylon resin (trade name: CM4000) was used instead of the polyolefin resin dispersion, and the total solid content concentration in the intermediate layer coating solution was 5% by mass. It was prepared as follows. As a result, the viscosity was 6.5 cp. Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 2)
In the preparation of the intermediate layer coating solution of Example 1, an alcohol-soluble nylon resin (trade name: CM4000) was used instead of the polyolefin resin dispersion, and the total solid concentration in the intermediate layer coating solution was 1% by mass. It was prepared as follows. As a result, the viscosity was 1.9 cp. Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 3)
In the preparation of the intermediate layer coating solution of Example 1, an alcohol-soluble nylon resin (trade name: CM4000) was used instead of the polyolefin resin dispersion, and the total solid content concentration in the intermediate layer coating solution was 16% by mass. It was prepared as follows. As a result, the viscosity was 22.5 cp. Other than that was carried out similarly to Example 1, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 20)
In the preparation of the intermediate layer coating solution of Example 1, a conductive layer was not provided as a lower layer of the intermediate layer, and the surface roughness Rz according to JIS B 0601 (1994) was 2.0 μm, and the surface was roughened. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the support was used. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 4)
In the preparation of the intermediate layer coating solution of Example 20, an alcohol-soluble nylon resin (trade name: CM4000) was used instead of the polyolefin resin dispersion, and the total solid content concentration in the intermediate layer coating solution was 5% by mass. It was prepared as follows. As a result, the viscosity was 6.5 cp. Other than that was carried out similarly to Example 20, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 20, and the results are shown in Table 1.

(Example 21)
In Example 20, an electrophotographic photosensitive member was produced in the same manner as in Example 20 except that the temperature of the hot water tank at the time of washing the support was 70 ° C. Evaluation was performed in the same manner as in Example 20, and the results are shown in Table 1.

(Comparative Example 5)
In Example 21, an alcohol-soluble nylon resin (trade name: CM4000) was used instead of the polyolefin resin dispersion, and the total solid concentration in the intermediate layer coating solution was adjusted to 5% by mass. As a result, the viscosity was 6.5 cp. Other than that was carried out similarly to Example 21, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 21, and the results are shown in Table 1.

(Example 22)
In the preparation of the coating solution for the intermediate layer of Example 1, instead of the tin oxide sol solution, 20 parts of titanium oxide (trade name: TTO55N, specific gravity 4.2, manufactured by Ishihara Sangyo Co., Ltd.) and 80 parts of IPA were mixed by a ball mill. 300 parts of time-dispersed titanium oxide dispersion was used. Next, an aqueous polyolefin resin dispersion is prepared by changing the water and ethanol ratio, and the intermediate layer has a total solid content concentration of 14 mass%, a viscosity of 18.2 cp, and a water content ratio of 4 mass% in the aqueous medium. A coating solution was prepared. An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the intermediate layer coating solution was used. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 23)
In the preparation of the intermediate layer coating solution of Example 22, an aqueous polyolefin resin dispersion was produced by changing the ratio of water and ethanol, the total solid content was 14% by mass, the viscosity was 19.8 cp, and water was contained in the aqueous medium. An intermediate layer coating solution having a ratio of 2% by mass was prepared. An electrophotographic photosensitive member was produced in the same manner as in Example 22 except that the intermediate layer coating solution was used. Evaluation was performed in the same manner as in Example 22, and the results are shown in Table 1.

(Example 24)
In Example 1, the conductive layer coating solution was dip coated and then dried at a temperature of 150 ° C. for 30 minutes to form a 30 μm conductive layer. The temperature of the intermediate layer coating solution immediately before dipping in the intermediate layer coating solution, that is, immediately before the support provided with the conductive layer descends toward the coating solution, was 22 ° C. Moreover, the temperature of the support body provided with the conductive layer carried through the drying process after coating for the conductive layer was 42 ° C. Otherwise, an electrophotographic photoreceptor was produced in the same manner as in Example 1. Evaluation was performed in the same manner as in Example 24, and the results are shown in Table 1.

(Comparative Example 6)
In Example 24, after the above coating liquid for conductive layer was dip-coated, this was dried at a temperature of 155 ° C. for 40 minutes to form a 30 μm conductive layer. The temperature of the intermediate layer coating solution was 22 ° C. immediately before dipping in the intermediate layer coating solution, that is, immediately before the support provided with the conductive layer was lowered toward the coating solution. Moreover, the temperature of the support body provided with the conductive layer carried through the drying process after application of the conductive layer was 47 ° C. Other than that was carried out similarly to Example 24, and produced the electrophotographic photoreceptor. Evaluation was performed in the same manner as in Example 24, and the results are shown in Table 1.

(Comparative Example 7)
In Example 20, an electrophotographic photosensitive member was produced in the same manner as in Example 20 except that the temperature of the hot water tank at the time of washing the support was 40 ° C. Evaluation was performed in the same manner as in Example 20, and the results are shown in Table 1.

(Comparative Example 8)
In Example 20, an electrophotographic photosensitive member was produced in the same manner as in Example 20, except that the temperature of the hot water tank at the time of washing the support was 45 ° C. Evaluation was performed in the same manner as in Example 20, and the results are shown in Table 1.

1 Electrophotographic Photosensitive Member 21 Support 22 Conductive Layer 23 Intermediate Layer 24 Charge Generation Layer 25 Charge Transport Layer

Claims (8)

Applying an intermediate layer coating solution on a support to form an intermediate layer; and
In the method for producing an electrophotographic photosensitive member having a step of forming a photosensitive layer by applying a photosensitive layer coating solution on the formed intermediate layer,
The temperature of the support when applying the intermediate layer coating solution on the support is T1 (° C.), and the temperature of the intermediate layer coating solution when applying the intermediate layer coating solution on the support is When T2 (° C), (T1-T2) is 3 ° C or higher and 20 ° C or lower,
The intermediate layer coating solution contains resin particles,
The total solid concentration in the intermediate layer coating solution is 10% by mass or more,
A method for producing an electrophotographic photosensitive member, wherein the viscosity of the intermediate layer coating solution measured at a temperature of 23 ° C./1 atm is 2.0 cp to 20.0 cp.   2. The electrophotographic image according to claim 1, wherein the intermediate layer coating solution is an aqueous dispersion containing resin particles having a volume average particle size of 0.05 μm or more and 0.50 μm or less measured using a light scattering particle size distribution meter. A method for producing a photoreceptor.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the resin particles are polyolefin resin particles. The polyolefin resin has the following (A1), (A2) and (A3), and the mass ratio of (A1), (A2) and (A3) of the polyolefin resin satisfies the following formulas (1) and (2) The method for producing an electrophotographic photosensitive member according to claim 3.
0.01 ≦ (A2) / {(A1) + (A2) + (A3)} × 100 ≦ 10 Formula (1)
(A1) / (A3) = 55/45 to 99/1 Formula (2)
(A1): Repeating structural unit represented by the following formula (11)

(In formula (11), R ^{11 to} R ¹⁴ each independently represents a hydrogen atom or an alkyl group.) (A2): Repeating structural unit represented by the following formula (21) or (22)

(In the formulas (21) and (22), R ^{21 to} R ²⁴ are each independently a hydrogen atom, an alkyl group, a phenyl group or —Y ²¹ COOH (wherein Y ²¹ is a single bond, an alkylene group or an arylene) R ²⁵ and R ²⁶ each independently represents a hydrogen atom, an alkyl group or a phenyl group, and X ²¹ represents —Y ²² COOCO.
Y ²³ — (wherein Y ²² and Y ²³ each independently represents a single bond, an alkylene group or an arylene group) represents a divalent group. However, at least one of R ^{21 to} R ²⁴ is a monovalent group represented by —Y ²¹ COOH. )
(A3): repeating structural unit represented by the following formula (31), (32), (33) or (34)

(In formulas (31) to (34), R ^{31 to} R ³⁵ each independently represent a hydrogen atom or a methyl group, and R ^{41 to} R ⁴³ each independently represents an alkyl group having 1 to 10 carbon atoms. R ^{51 to} R ⁵³ each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.) The method for producing an electrophotographic photosensitive member according to claim 4, wherein a mass ratio of (A1), (A2) and (A3) of the polyolefin resin satisfies the following formula.
0.01 ≦ (A2) / {(A1) + (A2) + (A3)} × 100 ≦ 5   The intermediate layer coating liquid is an aqueous dispersion containing resin particles, and the water content in the aqueous medium used for the preparation of the aqueous dispersion is 4% by mass or more. 2. A method for producing an electrophotographic photosensitive member according to item 1.   In the step of forming the intermediate layer by applying the intermediate layer coating solution on the support, a conductive layer is formed on the support, and the intermediate layer coating solution is formed on the support. The method for producing an electrophotographic photoreceptor according to claim 1, wherein the electrophotographic photoreceptor is applied on the layer.   Before the step of forming the intermediate layer by applying the intermediate layer coating solution on the support, the method further includes a step of cleaning the support, and the step of cleaning the support has a temperature of 80 ° C or higher. The method for producing an electrophotographic photosensitive member according to claim 1, comprising immersing the support in warm water.

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