JPS62208055A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve the lubricity, release property and cleaning property of a photosensitive body by incorporating a specific silicone comb type graft polymer and maleinimide resin into said body. CONSTITUTION:The silicone comb type graft polymer and maleinimide resin are incorporated into at least the layer furthest from the base body of the photosensitive body. The above-mentioned polymer consists of the copolymer of the resultant product of the condensation reaction of the silicone expressed by formula I and/or formula II and a compound expressed by formula III and a polymerizable unsatd. bond-contg. compd. e.g.: ((meth)acrylate). R1-R7, R11 in formulas denote an alkyl, aryl R8-R10 denote H, halogen, alkyl, etc.; X denotes a halogen, alkoxy; n denotes an average degree of polymn.; m denotes 1-3. The lubricity, release property and cleaning property of the surface of the photosensitive body are improved according to the above-mentioned constitution.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is an electrophotographic photosensitive material that can be widely used in electrophotographic application fields such as electrophotographic copying machines, laser beam printers, CRT printers, and electrophotographic plate making systems. Regarding the body.

[Conventional technology]

Inorganic photoconductive materials such as selenium, cadmium sulfide, and zinc oxide have conventionally been used as photoconductive materials for electrophotographic photoreceptors. On the other hand, organic photoconductive materials such as polyvinyl rubber, oxadiazole, and phthalocyanine have advantages over inorganic photoconductive materials, such as non-pollution and high productivity, but their low sensitivity has made it difficult to put them into practical use. For this reason, several methods have been proposed for exacerbating the problem, but it is known and put into practical use as an effective method to use a functionally separated photoreceptor in which a charge generation layer and a charge transport layer are laminated.

On the other hand, as a matter of course, electrophotographic photoreceptors are required to have predetermined sensitivity, electrical properties, and optical properties depending on the electrophotographic process to which they are applied. In particular, for photoreceptors that can be used repeatedly, the surface layer of the photoreceptor, that is, the layer furthest from the substrate, is directly exposed to electrical and mechanical external forces such as corona charging, toner development, transfer to paper, and cleaning processing. Since these materials are added, durability against them is required. Specifically, it is required to have durability against a decrease in sensitivity, a decrease in potential, an increase in residual potential due to deterioration due to ozone generated during corona charging, and the occurrence of surface abrasion and scratches due to rubbing.

In addition, adhesion of paper dust due to contact with paper is one of the causes of image fading under high humidity conditions, and toner filming and residual toner due to poor cleaning can significantly impair the resulting image. Therefore, there is a need to form a photoreceptor surface that is less susceptible to contamination and easier to remove.

Conventionally, various methods have been proposed to solve the above-mentioned drawbacks. As one of them, the use of maleimide resin as a binder for the surface layer is being considered. When used as a binder, it has a polar structure similar to charge transport agents, etc., so it has excellent compatibility and good electrophotographic properties. However, it has poor abrasion resistance, and when installed in an actual copying machine, Contact wear with cleaners, paper, etc. and toner fusion occur early.To improve this, the surface layer is given lubricity to reduce sliding resistance, resulting in less wear and toner retention. Attempts have been made to prevent fusion.Means include adding general coating film surface modifiers, ie, leveling agents, silicone oil, etc., and dispersing Teflon powder.

However, these general surface modifiers have poor compatibility with the components of the coating liquid to which they are added, so they migrate or ooze out onto the surface layer during long-term use, reducing the sustainability of their effects. There was a problem. In addition, when the surface layer itself forms a photoconductive layer, the surface modifier has poor compatibility with the photoconductive substance, and also tends to act as a trap for the movement of carriers due to photogeneration, resulting in repeated electrophotographic processes. There was a tendency for the residual charge to increase. On the other hand, a surface layer in which Teflon powder or the like is dispersed has problems such as poor dispersibility, decreased transparency, and carrier trapping.

[Problem that the invention seeks to solve]

The present invention solves the conventional problems and reduces the sliding resistance by increasing the lubricity of the surface.As a result, it has excellent wear resistance and slipperiness, which reduces the occurrence of toner fusion, etc. The purpose of the present invention is to provide an electrophotographic photoreceptor that does not require the above.

Another object of the present invention is to provide an electrophotographic photoreceptor that does not accumulate residual charge during repeated electrophotographic processes, has excellent stability, and can consistently produce high-quality images.

The present invention aims to achieve the above object by incorporating a specific silicone-based comb-shaped graft polymer and a maleimide-based resin into at least the layer of an electrophotographic photoreceptor that is farthest from the substrate.

[Means for solving problems]

That is, the present invention relates to general formula (I) (wherein R+, Rz, R3, R4, and Rs represent an alkyl group or an aryl group that may have a substituent, and n represents an average degree of polymerization) and /or general formula (n) ■ HO-+ S i O+-VH (II) , n indicates the average degree of polymerization. or R11 represents an alkyl group or an aryl group which may have a substituent, A represents an arylene which may have a substituent, and X represents a halogen atom or an aryl group which may have a substituent. (m is an integer of 1 to 3. The present invention is an electrophotographic photoreceptor characterized in that a polymer and a maleimide resin are contained at least in a layer furthest from a substrate.

The present invention will be explained in detail below.

As is known in the art, an electrophotographic photoreceptor has a photosensitive layer on a substrate and, if necessary, a non-photosensitive subbing layer, an intermediate layer, a surface layer, etc., and as the photosensitive layer. There are those that have a single layer structure and those that have a laminated structure of a charge generation layer and a charge transport layer. The present invention can be applied to all of these known types of electrophotographic photoreceptors, and includes at least the layer furthest away from the substrate (
As the surface layer (hereinafter referred to as the surface layer according to the present invention), for example, the charge generation layer or the charge transport layer in the non-photosensitive surface layer, the photosensitive layer having a single layer structure, the photosensitive layer having a laminated structure, etc. Contains a comb-type graft polymer and a maleimide resin.

The silicone-based comb-shaped graft polymer used in the present invention is a modified silicone which is a condensation reaction product of silicone represented by the following general formula (1) and/or general formula (n) and a compound containing the following general formula (III). It is obtained by copolymerizing a compound with a polymerizable functional group, and a silicone-containing side chain group made of modified silicone is bonded in a branched manner to a main chain made of a compound containing a polymerizable functional group. It has a similar structure.

General formula (I) However, R+, Rz, Rs, R4, and Rs represent an alkyl group or an aryl group that may have a substituent, and n represents an average degree of polymerization.

General formula (n) HO-+ 5iOh-H ■R1 However, R,, Rt represent an alkyl group or an aryol group which may have a substituent, and n represents an average degree of polymerization.

General formula (I[[) However, Ro + R9+ Rho represents a hydrogen atom, a halogen atom, an alkyl group or an aryl group which may have a substituent, and Ro represents an alkyl group or an aryl group which may have a substituent. A represents an arylene group which may have a substituent, X represents a halogen atom or an alkoxy group which may have a substituent, and m represents an integer of 1 to 3.

In the general formulas (I) and (n), R,, Rt.

Specifically, R3, R,, Rs, R&, and R7 are alkyl groups such as methyl, ethyl, propyl, and butyl, or aryl groups such as phenyl and naphthyl, and have substituents such as halogen atoms and lower alkyl groups. May have.

Preferred are methyl group and phenyl group.

n indicates an average degree of polymerization, and is in the range of 1 to 1000, preferably in the range of 10 to 500.

In the general formula (I[[), R1, R9 and R5° are
Specifically, hydrogen atoms, halogen atoms such as fluorine, chlorine, bromine, and iodine, alkyl groups such as methyl, ethyl, propyl, and butyl, or aryl groups such as phenyl and naphthyl, and substitution of halogen atoms and lower alkyl groups. It may have a group. Preferably it is a hydrogen atom.

Specifically, R11 is an alkyl group such as methyl, ethyl, propyl, butyl, or an aryl group such as phenyl or naphthyl, and may have a substituent such as a halogen atom. Preferred are methyl group and phenyl group.

Specifically, X is a hydrogen atom, a halogen atom such as fluorine, chlorine, bromine, or iodine, or an alkoxy group such as methoxy, ethoxy, propoxy, or butoxy, and may have a substituent such as a lower alkoxy group. Preferred are methoxy group, ethoxy group, and 2-methoxy-ethoxy group.

A is an arylene group such as phenylene, biphenylene, or naphthylene, and may have a substituent such as a halogen atom or a lower alkyl group. m is an integer from 1 to 3.

-a Specific examples of formulas (I) to (III) are shown below.

Specific example of general formula (1) CHs CHx CHx CHx CzHs C3H? C4H9CHs r C.I. Specific examples of general formula (II) disease CH.

26　　　　HO-f　S　i　Oh-Hs CH.

2Hs 27 HO-e Si Oh-Hs Ct H5 C2H? " 28 HO-+S i Oh-Hs Cx H'r C4Hq 29 HO-+S iOh-Hs C4H9 H3 ♂ 30 HO→S i Oh-Hs C, Hs CH3 31HO-f S i O)-H s C3H? Cz Hs 32 HO→ S i Oh-Hs C4Hq C4HmC1 33HO→SiO+r-H s 04H@CII CH'r 34 HO-+ S i Oh-HtH
sC1 H3 CZ Hs r ■ Specific example of general formula (I[[) Br Silicone represented by general formula (1) and/or general formula (II) and a compound containing general formula (I[I) as a constituent component. The condensation reaction proceeds very smoothly according to ordinary organic chemical reaction operations, and is described, for example, in JP-A-58-167606, which discloses a method for synthesizing comb-shaped graft polymers.
A stable modified silicone can be obtained by appropriately controlling the reaction molar ratio and reaction conditions according to JP-A-59-126478.

Compounds having a polymerizable functional group include macromonomers consisting of polymerizable monomers that do not have silicon atoms or relatively low molecular weight polymers with a molecular weight of about 1,000 to 10,000 that have a polymerizable functional group at the end. Examples of olefinic compounds include low molecular weight linear unsaturated hydrocarbons such as ethylene, propylene, and butylene, vinyl halides such as vinyl chloride and vinyl fluoride, and vinyl acetate. vinyl esters of organic acids such as styrene, styrene substitutes, and other vinyl aromatic compounds such as vinylpyridine and vinylnaphthalene; acrylic acid, including acrylic acid, methacrylic acid, and their esters, amides, and acrylonitrile;
Derivatives of methacrylic acid, N-vinylcarbazole, N-
Examples include N-vinyl compounds such as vinylpyrrolidone and N-vinylcaprolactam, and vinyl silicon compounds such as vinyltriethoxysilane. Disubstituted ethylenes can also be used, examples of which include vinylidene fluoride, vinylidene chloride, etc., as well as maleic anhydride, esters of maleic acid and fumaric acid, and the like.

In particular, acrylic esters, methacrylic esters, styrene, etc. are preferred from the viewpoint of affinity with maleimide resins.

Furthermore, the monomers can be used alone or in combination of two or more types.

Compounds having polymerizable functional groups used in the present invention include acrylamide, acrylic acid, acrylonitrile, 1.3-7
'Tadiene, 2-chloroethyl, vinyl ether, diethyl methacrylate, aminoethyl, diethyl fumarate,
N, N dimethylacrylamide, ethyl acrylate, ethylene, isobutylene, maleic acid, maleic anhydride,
Methacrylic acid, methyl acrylate, methacrylonitrile, methyl methacrylate, α-methylstyrene, p-methylstyrene, methyl vinyl ketone, fumaronitrile, propenyl ether, propylene, styrene, tetrafluoroethylene, vinyl acetate, N-vinylcarbazole , vinyl chloride, vinylidene chloride, vinylidene fluoride, vinylpyridine, 4-vinylpyridine, 2-vinylpyrrole, N-
Examples include vinylpyrrolidone, N-vinylsuccinimide, vinyl sulfide, and the like.

Radical polymerization and ionic polymerization such as solution polymerization, suspension polymerization, and bulk polymerization can be used as the polymerization method for silicone-based comb-shaped graft polymers, but radical polymerization by solution polymerization is preferred.

The copolymerization ratio is 5 to 90 as the silicone monomer content.
% by weight is preferred, and 10 to 70 weight % is more preferred.

The number average molecular weight of the obtained polymer is preferably 500 to 100,000, particularly preferably 1,000 to 50,000.

Since the silicone-based comb-shaped graft polymer of the present invention has such a structure, it has excellent compatibility with a coating solution containing a maleimide-based resin as a binder resin for forming a surface layer according to the present invention, and therefore The resulting coating film has good transparency and has a long-lasting effect without causing any migration or oozing onto the surface layer according to the present invention, and the silicone-containing part has no interface. Since it has excellent migration properties, surface modification can be achieved by adding a small amount. Furthermore, even when this additive is included in the surface layer, stable charging characteristics can be obtained without the accumulation of residual charges due to repeated electrophotographic processes.

The maleimide resin used in the present invention contains a polymer containing one or more repeating units represented by the following general formula (IV).

General formula (IV) (In the formula, R and -R represent a hydrogen atom, a phenyl group, an alkyl group that may have a substituent, or an aryl group, and n represents an average degree of polymerization.) Used in the present invention The maleimide resin can be obtained by copolymerizing a maleimide compound represented by the following general formula (V) with a compound having a polymerizable functional group such as an olefin, a vinyl compound, or an acrylic acid compound.

General formula (V) R,R.

+1 C=　C o=c　　c=.

(In the formula, R1, R1, and R are a hydrogen atom, a phenyl group, an alkyl group that may have a substituent, or an aryl group) Specific examples represented by general formula (V) are shown as structural formulas.

H C=　C I H ChzChz CH.

H CHtG HzC1 ■ CH3 N ■ Hx The method for obtaining the maleimide resin used in the present invention is to obtain one of the maleimide compounds represented by the general formula (V) above.
It can be obtained by copolymerizing one or more species with one or more compounds having a polymerizable functional group.

As the polymerization method, radical polymerization and ionic polymerization such as solution polymerization, suspension polymerization, and bulk polymerization can be applied, but radical polymerization by solution polymerization is simple and preferred.

In the present invention, the content of maleimide in the copolymer is preferably 5% or more, particularly 10 to 70%, and the molecular weight of the obtained polymer is 10.000 to i in terms of weight average molecular weight MW.
ooo, ooo especially 100.000~600.0
00 is preferred.

The amount of the silicone comb-shaped graft polymer added is suitably 0.01 to 10%, particularly preferably 0.05 to 5%, based on the solid weight of the surface layer.

If the amount added is less than 0.01%, a sufficient surface modification effect cannot be obtained, while if it exceeds 10%, the graft polymer will exist not only on the surface of the coating film but also in the bulk, so that it will not be the main component of the surface layer. Problems with compatibility with the component resins and photoconductive substances can cause whitening, and residual charges can accumulate when electrophotographic processes are repeated.

The present invention will be described in detail below, taking as an example the case where the photosensitive layer has a laminated structure of a charge generation layer and a charge transport layer, and the surface layer according to the present invention is the charge transport layer.

When producing the electrophotographic photoreceptor of the present invention, a cylindrical cylinder or film made of metal such as aluminum or stainless steel, paper, or plastic is used as the substrate. A subbing layer (adhesive layer) having a barrier function and a subbing function can be provided on these substrates.

The undercoat layer is formed to improve adhesion of the photosensitive layer, improve coating properties, protect the substrate, cover defects on the substrate, improve charge injection from the substrate, protect the photosensitive layer from electrical breakdown, etc. . Known materials for the undercoat layer include polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, copolymerized nylon, glue, gelatin, and the like. These are each dissolved in a suitable solvent and applied onto the substrate.

The film thickness is about 0.2 to 2μ.

In the functionally separated photoreceptor, the charge generating substances include selenium, selenium-tellurium, pyrylium, thiopyrylium dyes, phthalocyanine pigments, anthoanthrone pigments, dibenzpyrenequinone pigments, lanthrone pigments, trisazo pigments, disazo pigments, azo pigments, Indigo pigments, quinacridone pigments, asymmetric quinocyanine, quinocyanine, or the amorphous silicon described in JP-A-54-143645 can be used, and as the charge transport substance, pyrene, N-ethylcarbazole, N-isopropylcarbazole, N-methyl-N-phenylhydrazino-3-methylidene-9-ethylcarbazole, N,
N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, N,N-diphenylhydrazino-3-
Methylidene-10-ethylphenothiazine, N,N-diphenylhydrazino-3-methylidene-10-ethylphenoxazine, p-diethylaminobenzaldehyde
N,N-diphenylhydrazone, p-diethylaminobenzaldehyde-N-α-naphthyl-N-phenylhydrazino, p-pyrrolidinobenzaldehyde-N,N-diphenylhydrazone, 1,3.3-)dimethylindolenine-ω- Hydrazones such as aldehyde-N,N-diphenylhydrazone, p-diethylbenzaldehyde-3-methylbenzthiazolinone-2-hydrazone, 2,
5-bis(p-diethylaminophenyl")-1,3,
4-Oxadiazole, l-phenyl-3-(p-diethylaminostyryl)-5-(p-diethylaminophenyl) birapurine, 1-[quinolyl(21)]-3-(p
-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, 1-[pyridyl(2))-3
-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, 1-[6-medoxybilidyl (2)) -3-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline , 1-[Pyridyl(3))-3-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, 1-[Levidyl fzl)-3-(p-diethylaminostyryl)-5-(p- diethylaminophenyl)pyrazoline, 1-[pyridyl (2)) -3-(p
-diethylaminostyryl)-4-methyl-5-(p-
diethylaminophenyl)pyrazoline, ■-[pyridyl(2))-3-(α-methyl-p-diethylaminostyryl)-5(p-diethylaminophenyl)pyrazoline, 1-phenyl-3-(p-diethylaminostyryl)
Pyrazolines such as -4-methyl-5-(p-diethylaminophenyl)pyrazoline, 1-phenyl-3-(α-benzyl-p-diethylaminostyryl)-5(p-diethylaminophenyl)pyrazoline, spiropyrazoline, 2-( p-diethylaminostyryl)-6-ethylaminobenzoxazole, 2-(p-diethylaminophenyl)-4-(p-dimethylaminophenyl)
Oxazole compounds such as -5-, (2-chlorophenyl)oxazole, thiazole compounds such as 2-(p-diethylaminostyryl)-6-ethylaminobenzoxazole, bis(4-diethylamino-2-methylphenyl)- Triarylmethane compounds such as phenylmethane, 1,1-bis(4-N,N-diethylamino-
Polyarylalkanes such as 2-methylphenyl)hebutane and 1.1.2.2-tetrakis(4-N,N-dimethylamino-2-methylphenyl)ethane can be used.

The charge generation layer is prepared by dispersing the above charge generation substance together with 0.3 to 4 times the amount of a binder resin and a solvent using a method such as a homogenizer, ultrasonic waves, a ball mill, a vibrating ball mill, a sand mill, an attritor, or a roll mill. It is formed by coating and drying.

Its thickness is about 0.1 to 1 μm.

The charge transport layer is formed by dissolving a maleimide resin according to the present invention and a silicone comb-shaped graft polymer as a binder in a solvent together with a charge transport substance, and coating the mixture on the charge generation layer. The mixing ratio of charge transport material and binder resin is 2:1
The ratio is about 1:2.

Examples of solvents include ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate and ethyl acetate, aromatic hydrocarbons such as toluene and xylene, and chlorinated hydrocarbons such as chlorobenzene, chloroform, and carbon tetrachloride. used.

When applying this solution, coating methods such as dip coating, spray coating, spinner coating, bead coating, blade coating, and curtain coating can be used, and drying is carried out at 10°C to 200°C. , preferably 20°C
5 minutes to 5 hours at a temperature in the range of ~150°C, preferably 1
The drying can be carried out for 0 minutes to 2 hours under blow drying or stationary drying. The thickness of the generated charge transport layer is 5 to 20
It is about μ.

Further, the charge transport layer can contain various additives. Such additives include diphenyl, diphenyl chloride, 0-terphenyl, p-terphenyl, dibutyl phthalate, dimethyl glycol phthalate, dioctyl phthalate, triphenyl phosphoric acid, methylnaphthalene, benzophenone, chlorinated paraffin, dilaurylthiopropionate. , 3,5-dinitrosalicylic acid, and various fluorocarbons.

On the other hand, in a functionally separated photoreceptor having a charge generation layer as a surface layer, the maleimide resin and the silicone comb-shaped graft polymer according to the present invention can be used as a binder for a charge generation substance.

Furthermore, even in a single-layer type photoreceptor in which the photoreceptor layer is the surface layer according to the present invention, a maleimide resin and a silicone-based comb-shaped graft polymer can be used as a binder in the photoreceptor layer. When a non-photosensitive surface layer is provided on the surface, for example, as a protective layer, the maleimide resin and silicone comb-shaped polymer according to the present invention can be used as the material for forming the protective film.

Hereinafter, the present invention will be explained according to examples.

〔Example〕

The silicone-based comb-shaped graft polymer (sample Na w o ) used in the following examples is based on Japanese Patent Application Laid-Open No. 58-1676, which discloses a method for synthesizing a comb-shaped graft polymer.
06, the above general formula (
I) and/or a modified silicone which is a condensation reaction product of the silicone represented by the above general formula (II) and at least the above general formula (I[[), and a radically polymerizable monomer synthesized by radical copolymerization. The composition is shown in Table 1.

The structures of the synthesized silicone-type graft polymers are shown below as representative examples for samples Naa and h.

Sample a n: Average: 30 9 pieces q■: Positive integer A, /Bl: 30/70 (weight ratio) Sample h A t B tn: Average: 30 ptr qt' Positive integer At /B! : 30/70 (weight ratio) Example 1 10 parts (parts by weight, the same applies hereinafter) of cutic casein produced by New Sealant were weighed out, dispersed in 90 parts of water, and then dissolved by adding 1 part of aqueous ammonia. . On the other hand, hydroxypropyl methylcellulose resin (product name: Metrose 6)
Dissolve 3 parts of 0SH50 (manufactured by Shin-Etsu Chemical) in 20 parts of water,
Next, the two were mixed to prepare a coating solution for an undercoat layer.

This liquid was applied to one cylinder of 80φX 3 QO*m by dipping method and dried at 80° C. for 10 minutes to form an undercoat layer with a thickness of 2 μm.

Next, 10 parts of a disazo pigment having the following structural formula, 6 parts of cellulose acetate butyrate resin (trade name: CA B-381, manufactured by Eastman Chemical Co., Ltd.) and 60 parts of cyclohexanone were dispersed for 20 hours using a sand mill apparatus using lφ glass beads. Add 100 parts of methyl ethyl ketone to this dispersion,
It was applied by dip coating onto the above-mentioned undercoat layer and dried by heating at 100° C. for 10 minutes to form a charge generation layer with a coating weight of 0.1 g/rd.

Next, 10 parts of a hydrazone compound having the following structural formula and 10 parts of a resin obtained by copolymerizing phenylmaleimide and methyl methacrylate of Specific Example Hikari 123 of the general formula (V) were dissolved in 100 parts of dichloromethane. Add sample 1 to this solution.
0.2 part of a 1 kLa silicone comb-shaped graft polymer was added as a solid content. This solution was applied onto the charge generation layer and dried with hot air at 100° C. for 1 hour to form a charge transport layer with a thickness of 16 μm.

This is designated as sample 1. Electrophotographic photoreceptors similarly prepared using the silicone-based comb-shaped graft polymer of Sample Nl b w o are designated as Samples 2 to 15.

For comparison, a sample without the silicone comb-shaped graft polymer was prepared in the same manner as above.

These will be referred to as sample 16.

The durability of these samples was evaluated on 5,000 sheets using an electrophotographic process consisting of -5.5 kV, corona charging, image exposure, dry toner development, toner transfer to plain paper, and cleaning with a urethane rubber blade. The results are shown in Table 1 below.

Table 1 Example 2 10 parts of the hydrazone compound used in Example 1 and the general formula (
, 10 parts of the resin copolymerized with methylmaleimidostyrene of Specific Example N1124 of V) was dissolved in 80 parts of monochlorobenzene. To this liquid, 0.4 part of silicone comb-shaped graph I polymer of sample mh was added as solid content. This solution was applied onto a substrate coated up to the charge generation layer prepared in the same manner as in Example 1, and dried with hot air at 100° C. for 1 hour to form a charge transport layer with a thickness of 16 μm. This is sample 1
Set it to 7.

For comparison, a sample without the silicone comb-shaped graft polymer was prepared in the same manner as above.

This is designated as sample 18.

The durability of these samples was evaluated under the same conditions as in Example 1. The results are shown in Table 2.

Table 2 Example 3 An aluminum cylinder of 80φ x 300 liters was used as a base, and polyamide resin (product name: Amilan CN-800
A 5% methanol solution of 0.0 (manufactured by Toshi Co., Ltd.) was applied by a dipping method to form a 1 μm thick undercoat layer.

Next, 12 parts of a pyrazoline compound having the following structural formula and 10 parts of the maleimide resin synthesized in Example 2 were dissolved in 60 parts of monochlorobenzene.

This liquid was dip coated onto the undercoat layer and dried at 100° C. for 1 hour to form a charge transport layer with a thickness of 14 μm.

Next, 10 parts of a bisazo pigment having the following structural formula was added to 100 parts of a 10 wt% dioxane solution of the maleimide resin synthesized in Example 1, and dispersed for 20 hours using a sand mill apparatus using glass beads. Samples ll & lc were added to this dispersion.
One part of silicone-based comb-shaped graft polymer was added as a solid content. This solution was applied onto the charge transport layer and dried at 100° C. for 20 minutes to form a charge generation layer with a thickness of 2 μm.

This is designated as sample 19. For comparison, a sample without the silicone comb-shaped graft polymer was prepared in the same manner as above. This is designated as sample 20.

The sample thus obtained was attached to an electrophotographic copying machine having +5.6 kV corona charging, image exposure, dry toner development, toner transfer to plain paper, cleaning process using a urethane rubber blade, etc., at 32.5°C and RH90. Durability evaluation was conducted on 3000 sheets in an environment of 30%. The results are shown in Table 3.

Table 3 Example 4 10 parts of the hydrazone compound used in Example 1 and 10 parts of the maleimide resin synthesized in Example 2 were dissolved in 60 parts of monochlorobenzene. This solution was applied by dip coating onto the undercoat layer formed in the same manner as in Example 3, and dried at 100° C. for 1 hour to form a charge transport layer with a thickness of 15 μm.

Next, 10 parts of the bisazo pigment used in Example 3 was added to 100 parts of a monochlorobenzene solution containing 10-t% of the maleimide resin synthesized in Example 2, and dispersed for 20 hours using a sand mill apparatus using glass beads. One part of sample Nnj silicone-based comb-shaped graft polymer was added as a solid content to this dispersion.

This solution was pushed up and applied onto the charge transport layer at 10'C2.
After drying for 0 minutes, a charge generation layer having a thickness of 2.5 μm was formed.

This is designated as sample 21. For comparison, a sample without the silicone comb-shaped graft polymer was prepared in the same manner as above. This is designated as sample 22.

The durability of these samples was evaluated under the same conditions as in Example 3. The results are shown in Table 4.

Table 2 Example 5 Two parts of the maleimide resin synthesized in Example 1 were dissolved in 100 parts of dichloromethane. Add sample IVhe to this solution.
of silicone-based comb-shaped graft polymer with a solid content of 0.
Added 15 parts. This solution was spray applied onto an electrophotographic photoreceptor prepared in the same manner as Sample 6 of Example 1, and
It was dried for C5 minutes to form a 0.5 μm protective layer. This is designated as sample 23.

Similarly, 2 parts of the maleimide resin synthesized in Example 2 was dissolved in 100 parts of monochlorobenzene, and sample N
A solid content of 0.5 part of a silicone comb-shaped graft polymer of UT was added. This solution was spray-coated onto an electrophotographic photoreceptor prepared in the same manner as Sample 18 of Example 2.
It was dried at 0°C for 5 minutes to form a 0.4μ protective layer. This is designated as sample 24. The durability of 3000 sheets of these samples was evaluated under the same conditions as in Example 1. The results are shown in Table 5.

Table 5 Comparative Examples Samples prepared in the same manner as in Example 1 were used as Sample 25, except that 1.0 part of silicone oil (trade name: KF96 manufactured by Shin-Etsu Silicone ■) was used as a solid content in place of the silicone-based comb-shaped graft polymer. do.

Sample 26 is a sample prepared in the same manner as in Example 4, except that 1.0 part of the above silicone oil was used. Durability evaluation of these samples was carried out under the same conditions as in Examples 1 and 3, but there was a significant amount of blurring due to external forces, and the degree of fogging increased due to repeated copying. Further, when Samples 25 and 26 were observed one month after they were prepared, it was found that the silicone oil had migrated to the surface layer and stood out in the form of a stain. On the other hand, such changes over time were not observed in Samples 1 to 15, 17, 19.21, and 23.24 to which silicone-based comb-shaped graft polymers were added, and they exhibited the same appearance and characteristics as the initial stage.

Example 6 Sample N11.17.25 was then attached to an electrophotographic copying machine equipped with a -5.5 kV corona charger and subjected to an empty charging durability test of 5,000 copies at room temperature. The potential and the variation in the VL potential after 7.5 lux of seconds were measured. The results are shown in Table 6.

Table 6 50% of the sample with silicone oil added as shown in the table above
The vL fluctuation after 00 sheets durability is very large.

In contrast, it can be seen that the product of the present invention has an extremely stable potential during durability.

Example 7 Next, for samples 1111121 and 26, +5.5k
Attach it to an electrophotographic camera equipped with a V corona charger and leave it at room temperature.
An empty charging durability test was conducted on 3,000 sheets at room temperature, and fluctuations in the Vo potential and the VL potential after exposure to light at 7.5 lux for seconds were measured. The results are shown in Table 7.

Table 7 As shown in the table above, 3 samples added with silicone oil
The VL fluctuation after running for 000 sheets is very large. On the other hand, in the product of the present invention, the durability fluctuation is small.

Example 8 3 parts of a disazo pigment having the following structural formula, 10 parts of the maleimide resin used in Example 1, and 50 parts of monochlorobenzene were dispersed for 20 hours in a sand mill apparatus using 1φ glass beads. Add 11 ha of iJ material to this liquid as a solid content of silicone comb-shaped graft polymer.
, 2 parts, hydrazone compound 1 having the structural formula shown in Example 1
0 parts was added and dissolved. This dispersion solution was applied by dip coating onto a substrate having an undercoat layer prepared in the same manner as in Example 1.
The photoconductive layer was dried at 00° C. for 1 hour to form a 19 μm photoconductive layer. This is designated as sample 27.

For comparison, a sample without the silicone comb-shaped graft polymer was prepared in the same manner as above.

This is designated as sample 28.

The durability of these samples was evaluated under the same conditions as in Example 1. The results are shown in Table 8.

Table 8 Comparative Examples A sample prepared in the same manner as Example 8 was used as Sample 29, except that 1.0 part of silicone oil (trade name: KF96 Shin-Etsu Silicone was used as the molding component) in place of the silicone-based comb-shaped graft polymer. do.

Durability evaluation of this sample was conducted under the same conditions as in Examples 1 and 3, but there was considerable blurring, and the degree of fogging increased due to repeated copying. Further, when Sample 29 was observed one month after its preparation, it was found that the silicone oil had migrated to the surface layer and stood out in the form of a stain. On the other hand, in the sample to which the silicone-based comb-shaped graft polymer was added, no such change over time was observed, and the same observation and characteristics as in the initial stage were observed.

Example 9 Next, regarding the samples 1 to 30, the frictional force between the urethane rubber blade and the surface layer and the sample Na15 to 20.25 to
Regarding No. 29, the amount of abrasion of the surface layer was measured after 1000 sheets of A4 paper were actually burned. The results are shown in Table 9.

Table 9 *2 Amount of abrasion: Initial surface layer film thickness - Surface layer film thickness after durability As shown in the table above, the product of the present invention to which silicone-based comb-shaped graft polymer was added and the comparative sample to which silicone oil was added had no additive. Frictional resistance is significantly lower than that of the sample.

However, regarding the amount of abrasion, the sample to which the silicone-based comb-shaped polymer of the present invention was added has the smallest value, ie, shows that it is difficult to abrade.

Furthermore, as mentioned above, silicone oil-added systems are inferior in storage stability and potential stability during durability.

〔Effect of the invention〕

As is clear from the above, the electrophotographic photoreceptor of the present invention has excellent surface lubricity, low slip resistance, and wear resistance by blending a specific silicone-based comb-shaped graft polymer with maleimide-based resin. Excellent and imparts durability to the photoreceptor. In addition, the slip resistance is low, there are no cleaning defects such as toner fusion, and high-quality images can always be obtained.

Claims (7)

[Claims] (1) General formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R_1, R_2, R_3, R_4, R_5 represent an alkyl group or an aryl group that may have a substituent. , n indicates the average degree of polymerization) and/or general formula (II) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (II) (In the formula, R_6 and R_7 are alkyl groups that may have substituents or represents an aryl group, and n represents the average degree of polymerization) and at least the general formula (III) ▲ Numerical formula, chemical formula, table, etc. ▼ (III) (In the formula, R_8, R_9, R_1_0 are hydrogen atoms , represents a halogen atom, an alkyl group or an aryl group that may have a substituent, R_1_1 represents an alkyl group or an aryl group that may have a substituent, and X represents a halogen atom, an alkyl group that may have a substituent, or an aryl group that may have a substituent. a silicone-based comb-shaped graft polymer which is a copolymer of a condensation reaction product with a compound represented by (m is an integer of 1 to 3) and a polymerizable unsaturated bond-containing compound, and malein. An electrophotographic photoreceptor characterized in that an imide resin is contained at least in a layer furthest from a substrate. (2) The electrophotographic photosensitive material according to claim (1), which has a photosensitive layer and a non-photosensitive surface layer as constituent components, and the layer that is furthest away from the substrate is the non-photosensitive surface layer. body. (3) The electrophotographic photoreceptor according to claim (2), wherein the photosensitive layer has a laminated structure of a charge generation layer and a charge transport layer. (4) The electrophotographic photoreceptor according to claim (1), which has a photosensitive layer as the layer furthest from the substrate. (5) The electronic device according to claim (1), which has a photosensitive layer having a laminated structure of a charge generation layer and a charge transport layer as a component, and the charge transport layer is the layer furthest away from the substrate. Photographic photoreceptor. (6) The electronic device according to claim (1), which has a photosensitive layer having a laminated structure of a charge generation layer and a charge transport layer as a component, and the charge generation layer is the layer furthest away from the substrate. Photographic photoreceptor. (7) One of claims (1) to (6), wherein the content of the silicone comb-shaped graft polymer in the layer furthest from the substrate is within the range of 0.01 to 10% by weight. The electrophotographic photoreceptor described in .