JPH0293540A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve the electrostatic characteristics of the photosensitive body and to reproduce the copied image faithful to an original picture by respectively specifying the weight average mol. wt. of a binder resin and the repeating unit of the polymn. component incorporated therein and incorporating one kind of a specific resin therein. CONSTITUTION:At least one kind of resins which are the polymers having 1X10<3> to 5X10<4> weight average mol. wt. and contg. >=30wt.% at least one repeating units expressed by the formula I or the formula II as the polymn. component and is formed by bonding at least one of acidic groups such as -PO3H2 group, -SO3H group, -SH group, and phenolic OH group as well as cyclic acid anhydride-contg. groups only to one terminal of this polymer main chain. In the formulas I, II, X1 and X2 respectively independently denote a hydrogen atom, chlorine atom, bromine atom, etc.; W1 and W2 respectively independently denote a direct bond coupling -COO- and benzene ring or connection group of 1 to 4 pieces of connecting atoms. The electrophotographic sensitive body having the excellent electrostatic characteristic and the image pickup characteristic is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor with electrostatic properties and moisture resistance.

In particular, it relates to a CPC photoreceptor with excellent performance.

(Prior Art) Electrophotographic photoreceptors have various configurations in order to obtain predetermined characteristics or depending on the type of electrophotographic process to which they are applied.

As representative electrophotographic photoreceptors, there are photoreceptors having a photoconductive layer formed on a support and photoreceptors having an insulating layer on the surface, which are widely used.

Photoreceptors, consisting of a support and at least one photoconductive layer, are used for imaging by most common electrophotographic processes, ie, charging, imagewise exposure and development, and optionally transfer.

Furthermore, a method of using an electrophotographic photoreceptor as an offset original plate for direct plate making is widely used. Particularly in recent years, direct electrophotographic lithography has become important as a method for printing high-quality printed matter on the order of several hundred to several dozen sheets.

The binder used to form the photoconductive layer of the electrophotographic photoreceptor has excellent film-forming properties and the ability to disperse photoconductive powder into the binder, and also has excellent properties in the formation of the formed recording layer. It has good adhesion to the substrate, and the photoconductive layer of the recording layer has excellent charging ability, has low dark decay, large light decay, and low pre-exposure fatigue. It is necessary to have various electrostatic properties such as the need to stably maintain these properties and excellent imaging performance.

Examples of resins that have been known for a long time include silicone resin (Japanese Patent Publication No. 34-6670), styrene-butadiene resin (
Acrylic resin, maleic acid resin, polyamide (Japanese Patent Publication No. 35-11219), vinyl acetate resin (Japanese Patent Publication No. 41-2425), vinyl acetate copolymer (Japanese Patent Publication No. 41-2426), Acrylic resin (Japanese Patent Publication No. 35-11216), acrylic ester copolymer (e.g. Japanese Patent Publication No. 35-11219, Japanese Patent Publication No. 36-85)
No. 10, Japanese Patent Publication No. 4i-13946, etc.) are known.

However, electrophotographic light-sensitive materials using these resins lack 1) affinity with photoconductive powder, resulting in poor dispersibility of the coating solution. 2) Low chargeability of the photoconductive layer, 3
4) The quality of the image area of the copied image (particularly halftone reproducibility and resolution) is poor; 4) The environment at the time of creating the copied image (e.g. high temperature and high humidity;
The problem was that the image quality was easily affected by low temperatures (low temperature, low humidity, etc.).

Various methods have been proposed to improve the electrostatic properties of the photoconductive layer, and one such method is to use a compound containing a carboxyl group or a nitro group in an aromatic ring or a furan ring, or a dicarboxylic acid anhydride. Japanese Patent Publication No. 42-6878 and Japanese Patent Publication No. 45-3073 disclose a method of further combining materials to coexist in a photoconductive layer. However, even the photosensitive materials improved by these methods do not have sufficient electrostatic properties, and none particularly have excellent light attenuation properties. Therefore, in order to improve the lack of sensitivity of this photosensitive material, a method of adding a large amount of sensitizing dye to the photoconductive layer has been conventionally used, but the photosensitive materials produced by this method have a remarkable whiteness. This has caused problems such as deterioration of the quality of the recording medium and, in some cases, deterioration of the dark decay of the photosensitive material, making it impossible to obtain a sufficient copy image.

On the other hand, Japanese Patent Laid-Open No. 6010254 discloses a method of adjusting the average molecular weight of a resin used as a binder resin for a photoconductive layer. That is, acrylic resin with an acid value of 4 to 50 and an average molecular weight distribution of 103 to 104;
A technique has been described for improving electrostatic properties (particularly repeatability as a PPC photoreceptor), moisture resistance, etc. by using together components having a distribution of 2.times.105.

Furthermore, research into lithographic printing original plates using electrophotographic photoreceptors is being carried out, and a binding agent for the photoconductive layer that has both the electrostatic properties of an electrophotographic photoreceptor and the printing properties of a printing original plate is being actively researched. As a resin, for example, in Japanese Patent Publication No. 50-31011, Mwl, 8 to 10
A combination of a resin having an O' temperature of 7810 to 80°C and a copolymer consisting of a (meth)acrylate monomer and a monomer other than fumaric acid, and JP-A-53-54027
In this issue, a terpolymer containing a (meth)acrylic acid ester having a substituent having a carboxylic acid group separated from an ester bond by at least 7 atoms is used, and JP-A No. 5
In No. 4-20735 and JP-A No. 57-202544,
Those using quaternary or penta-component copolymers containing acrylic acid and hydroxyethyl (meth)acrylate, and those using JP-A No. 5
No. 8-68046 discloses that a terpolymer containing a (meth)acrylic acid ester having an alkyl group having 6 to 12 carbon atoms as a substituent and a carboxylic acid-containing vinyl monomer is used as an insensitive resin for the photoconductive layer. It is stated that it is effective in improving the chemical properties.

(Problems to be Solved by the Invention) However, even if the resin is said to be effective in the above-mentioned electrostatic properties and moisture resistance properties, when actually evaluated, it shows that it is particularly effective in charging properties, dark charge retention properties, and photosensitivity. There were problems with electrostatic properties such as , smoothness of the photoconductive layer, etc., and it was not practically satisfactory.

Even with binder resins that are said to have been developed as original plates for electrophotographic planographic printing, when actually evaluated, there were problems with the above-mentioned electrostatic properties, scumming of printed matter, and the like.

Furthermore, the scanning exposure method using semiconductor laser light requires longer exposure time than the conventional simultaneous exposure method of the entire surface using visible light, and there are restrictions on the exposure intensity, so electrostatic properties, especially dark charge retention, are Higher performance is required in terms of sensitivity and photosensitivity.

The present invention is intended to improve the problems of conventional electrophotographic photoreceptors as described above.

An object of the present invention is to provide a high-quality electrophotographic photoreceptor that has improved electrostatic properties (particularly dark charge retention and photosensitivity) and reproduces copied images that are faithful to original images.

Another object of the present invention is to provide an electrophotographic photoreceptor that produces clear, high-quality images even when the environment during copy image formation fluctuates, such as low temperature and low humidity, or high temperature and high humidity.

Another object of the present invention is to provide a CPC electrophotographic photoreceptor with excellent electrostatic properties and low environmental dependence.

Another object of the present invention is to provide a lithographic printing plate which can be used as an electrophotographic lithographic printing original plate and which can produce printed matter that does not cause any scumming.

(Means for Solving the Problem) The above problem is an electrophotographic photoreceptor having a photoconductive layer containing at least an inorganic photoconductive material and a binder resin, in which the binder resin has a layer of 1×10 3 to 5×10 4 . It is a polymer having a weight average molecular weight and containing the following repeating unit (i) as a polymerization component, and - only at one end of the polymer main chain.
PO, 82 group, -SO, I (group, ○ CO Kano group, -P -OH group (R is a hydrocarbon group having 1 to 10 carbon atoms or -OR'(R' is a hydrocarbon group having 1 to 10 carbon atoms) (indicating a group)), a -3H group, an acidic group of a phenolic DH group, and a cyclic acid anhydride-containing group. Electrophotographic photoreceptor.

(i) At least one represented by formula (1) or formula (I[)
30% by weight or more of repeating units Formula (1) C)
13 Formula (n) CH.

(wherein, Xl and X are each independently a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a chlorine atom, a bromine atom, -coy, or -COOY, ~10 hydrocarbon groups).

However, both x1 and x2 do not represent hydrogen atoms. W and W2 each represent a direct bond or a connecting group having 1 to 4 connected atoms that connects -000- to the benzene ring. ) Furthermore, when the resin contained in the binder resin further contains the repeating unit (ii) below as a copolymerization component in addition to the repeating unit (i) above, the film strength is further improved and the durability is improved. It was found that an electrophotographic photoreceptor with excellent printability could be obtained.

(ii) 1 to 20% by weight of at least one repeating unit containing a thermally and/or photocurable functional group. It may contain more than one species.

The conventionally known acidic group-containing binder resins as mentioned above are mainly used for offset masters, and their molecular weight is large (for example,
×104 or more), and these copolymers were random copolymers, and the acidic group-containing copolymer components were randomly present in the polymer main chain.

On the other hand, the binder resin used in the present invention has an acidic group and/or a cyclic acid anhydride-containing group (hereinafter, the term acidic group also includes a cyclic acid anhydride-containing group unless otherwise specified). is a polymer containing a methacrylate component which is bonded to the end of the polymer main chain and has a specific substituent as a polymerization component, and preferably has a heat and/or photocurable component as a further copolymerization component. It is a copolymer containing a component containing a functional group.

The present inventors have discovered that the acidic group at the end of the polymer main chain adsorbs to the stoichiometric defects of the inorganic photoconductor and improves the coverage of the photoconductor surface. It has been found that the photoconductor is sufficiently dispersed and agglomeration is suppressed while compensating for trapping and improving humidity properties. By using the polymer as the main component, the electrophotographic properties (charging property, D, RoRo, photosensitivity) are significantly improved, and it is almost unaffected by changes in humidity. It has been found that it exhibits stable and high performance electrophotographic properties.

Furthermore, the surface of the photoconductor becomes smooth.

When a photoreceptor with a rough surface of the photoconductive layer is used as an electrophotographic lithographic printing original plate, the dispersion state of the photoconductor particles and binder M resin is not appropriate, and the photoconductive layer is damaged in the presence of aggregates. As a result, even if desensitization treatment is performed using a desensitization treatment liquid, the non-image area cannot be made uniformly and sufficiently hydrophilic.
This causes adhesion of printing ink during printing, resulting in background smudges in non-image areas of printed matter.

On the other hand, in the case of the binder resin according to the present invention, there was a concern that the film strength would be weakened, but by sufficiently dispersing the photoconductor and adsorbing and coating the particle surface, the film properties were maintained. It has been found that the film has sufficient film strength for use as a CPC photoreceptor or as an offset original plate for printing several tens of sheets.

When the resin of the present invention further contains at least one heat-curable and/or photo-curable functional group, the functional group appropriately crosslinks the polymers, thereby strengthening the mutual bond between the polymers. It has been found that the strength of the film can be improved. Therefore, the resin of the present invention further containing a heat-curable and/or photo-curable functional group can interact between the binder resin and the inorganic photoconductor particle surface without hindering the proper adsorption and coating of the binder resin. This has the effect of further improving the film strength. That is, by containing at least one type of heat- and/or photo-curable functional group and appropriately crosslinking the polymers in the film, the film strength can be improved and an offset original plate that can print a larger number of sheets can be obtained. understood.

First, the binder resin used in the present invention does not contain the acidic group in the side chain connecting to the main chain of the polymer, but only at the end of the main chain, and has a weight average molecular weight of 1X103 to 5XIO. '
It is a resin.

The weight average molecular weight of the resin is preferably 1X10' to 2X
10', more preferably 3X10' to 1X10'.

The photoreceptor using the resin of the present invention exhibits stable and high-performance electrophotographic properties even when environmental conditions vary significantly from high temperature and high humidity to low temperature and low humidity. When using a resin with a molecular weight of 2 XIO' or less, higher properties can be maintained.

If the molecular weight of the binder resin is smaller than I This is not preferable because photographic properties (especially initial potential and dark decay retention rate) cannot be maintained.

The amount of the acidic group present in the polymer is preferably 0.5 to 10 parts by weight, more preferably 2 to 8 parts by weight per 100 parts by weight of the polymer.

If the content of acidic groups bonded to the terminals of the polymer main chain in the binder resin is less than 0.5% by weight, the initial potential will be low and sufficient image density will not be obtained.

On the other hand, if the acidic group content is more than 10% by weight, the dispersibility will be lowered, the film smoothness and high-humidity electrophotographic properties will be lowered, and furthermore, background smear will increase when used as an offset master.

The glass transition point of the resin of the present invention is preferably in the range of -10°C to 110°C, more preferably -5°C to 90°C.
It is.

The repeating unit (i) contained in the binder resin of the present invention in an amount of 30% by weight or more as a polymerization component or copolymerization component is represented by the above formula (1) or (II).

In formula (1), in addition to hydrogen, chlorine, and bromine atoms as preferred X and X2, preferred hydrocarbon groups include alkyl groups having 1 to 4 carbon atoms (e.g., methyl, ethyl, propyl, butyl group, etc.), aralkyl group having 7 to 9 carbon atoms (e.g. benzyl group, phenethyl group, 3-phenylpropyl group, chlorobenzyl group, dichlorobenzyl group, bromobenzyl group, methylbenzyl group, methoxybenzyl group, chloro-methyl -benzyl group, etc.), aryl group (e.g. phenyl group, tolyl group, xyl group, bromophenyl group, methoxyphenyl group, chlorophenyl group, dichlorophenyl group, etc.), and -COY
, and -COOY2 (preferred examples of Y and Y2 include those described above as preferred hydrocarbon groups). However, xl and x
Both 2 never represent a hydrogen atom.

In formula (I), W is a direct bond connecting -C00- and a benzene ring, or (CH2), (n represents an integer of 1 to 3), -C112CH20CO-(CH2
0).

(m represents an integer of l or 2), -CH,C)12
Represents a linking group having 1 to 4 linking atoms, such as 0-.

1l12 in formula (II) represents the same content as Wl.

In the present invention, the amount of the single unit corresponding to the repeating unit represented by formula (1) or (II) is 30% by weight or more and 100% by weight or less, preferably 60% by weight or more and 100% by weight or less.

Specific examples of the repeating unit (i) represented by formula (I) or (II) used in the present invention are listed below. but,
The scope of the present invention is not limited thereto.

CH3 2H5 CH3 C8゜CH3 C11゜CH3 L CH3 shi+13 CH3 C11゜CH3 i -25) lh i -35) COOC11゜shi■koi -37) i -39) i -40) shiυU1.1113 Also, this Among the acidic groups bonded only to one end of the polymer main chain in the resin of the invention, a preferred acidic group is -P03H
, group, -5038 group, -COO) group, -P-DH group, and cyclic acid anhydride-containing group.

OR' ○ In the P-OH group, R is a hydrocarbon group or OR' (
R' represents a hydrocarbon group), and R and R' preferably represent an aliphatic group having 1 to 22 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group). group, dodecyl group, octadecyl group, 2-
Chloroethyl group, 2-methoxyethyl group, 3-ethoxypropyl group, allyl group, crotonyl group, butenyl group, cyclohexyl group, benzyl group, phenethyl group, 3-phenylpropyl group, methylbenzyl group, chlorobenzyl group, fluorobenzyl group , metquinbenzyl group, etc.), or an optionally substituted aryl group (e.g., phenyl group, tolyl group, ethylphenyl group, flobyrphenyl group, chlorophenyl group, fluorophenyl group, bromophenyl group, chloro-methyl-phenyl group) group, dichlorophenyl group, methoxyphenyl group, cyanophenyl group, acetamidophenyl group, fluorophenyl group, butoxyphenyl group, etc.).

In addition, the cyclic acid anhydride-containing group refers to a group containing at least one cyclic acid anhydride, and examples of the cyclic acid anhydride include aliphatic dicarboxylic acid anhydride and aromatic dicarboxylic acid anhydride. Can be mentioned.

Examples of aliphatic dicarboxylic anhydrides include amber fIJ
, anhydride ring, glutaconic anhydride ring, maleic anhydride ring, cyclopentane-12-dicarboxylic anhydride ring, cyclohexane-12-dicarboxylic anhydride ring, cyclohexene-1,2-dicarboxylic anhydride ring, Examples include 2,3-bicycloC2,2,2]octanedicarboxylic anhydride rings, and these rings include, for example, halogen atoms such as chlorine atoms and bromine atoms, methyl groups, ethyl groups, butyl groups, and hexyl groups. Alkyl groups such as groups may be substituted.

Examples of aromatic dicarboxylic anhydrides include phthalic anhydride rings, naphthalene dicarboxylic anhydride rings, pyridine-dicarboxylic anhydride rings, and thiophene-dicarboxylic anhydride rings. , for example, halogen atoms such as chlorine atom and bromine atom, alkyl groups such as methyl group, ethyl group, propyl group, butyl group, hydroxyl group,
It may be substituted with a cyano group, a nitro group, an alkoxylcarbonyl group (as an alkoxy group, for example, a methoxy group, an ethoxy group, etc.), or the like.

The polymer of the present invention may be synthesized such that the acidic group is bonded to the terminal of the main chain of the polymer consisting of at least the polymerization component (i) above. Specifically, a method using a polymerization initiator containing the acidic group or a functional group that can be converted later into the acidic group, or a method using a polymerization initiator containing the acidic group or a functional group that can be converted later into the acidic group. It can be produced by a method using a chain transfer side, a method using a combination of the above two methods, and a method of introducing the functional group by utilizing a termination reaction in an anionic polymerization method.

For example, P, Dreyfuss, R, P, Quirk.
, Encycle, Polym.

Sci, Eng, 7.55H1987>, V, Per
cec, Appl, Polym.

Sci, 285.95 (1985), P, F, Re
mpp, Snake, Fra'nta, Adv.

Polym, Sci, 58.1 (1984), Y, Y
amashita, J., Appl.

Polym, Sci, Appl, Polym, Symp
, 36.193 (1981), R.

Asami, M., Takaki, Makromol, C.
Hem, 5uppl, 12.163 (1985).

Furthermore, the "thermal and/or photocurable functional group" in the repeating unit (ii) that can be preferably included in the present invention refers to a functional group that causes a resin curing reaction with at least one of heat and light. say.

In the present invention, when a copolymerization component containing a nuclear heat and/or photocurable functional group is present, the amount thereof is as follows:
It is preferably 1 to 20% by weight.

If the content of heat- and/or photo-curable functional groups in the binder resin is less than 1% by weight, the curing reaction will be insufficient, making it impossible to obtain the effect of improving film strength due to the curable functional groups. If the content is more than 20%, the degree of curing of the film becomes too high, the electrophotographic properties deteriorate, and furthermore, background smear increases when used as an offset master, which is not preferable.

Specific examples of photocurable functional groups include Hideo Inui, Gentabe Nagamatsu, "Photosensitive Polymer" (Kodansha, published in 1977), Takahiro Tsunoda, "New Photosensitive Resin" (published by Printing Society Publishing Department, published in 1981), G, E, Green and B, P, 5tr
ark, J. Macr.

Sci, Reas, Macro Chem, C21 (
2), 187-273 (1981-82), C, G,
Rattey, 'Photopolymiriza
tion of Surface Coatings” (
A. Wiley InterScience Pub.

Functional groups used in conventionally known photosensitive resins and the like are used as the photocurable resins cited in reviews such as 1982).

Furthermore, the "thermosetting functional group" in the present invention refers to a functional group other than the above-mentioned acidic group. , Yuji Harasaki [Latest Binder Technology Handbook J Chapter 11-1 (General Technology Center, published in 1985), Accompanied by Otsu [Synthesis, design and development of new applications of acrylic resins] (Chubu Business Development Center Publishing Department, published in 1985), Omori The functional groups cited in the review by Eizo [Functional Acrylic Resins] (Technosystem, published in 1985) can be used.

For example, -〇H group, -3H group, -NH, group, NHR+ group (R1 represents a hydrocarbon group, for example, an optionally substituted alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group) , butyl group, hexyl group, octyl group,
Decyl group, 2-chloroethyl group, 2methoxyethyl group,
2-cyanethyl group, etc.), an optionally substituted cycloalkyl group having 4 to 8 carbon atoms (e.g., cycloheptyl group, cyclohexyl group, etc.), an optionally substituted aralkyl group having 7 to 12 carbon atoms (e.g., benzyl group) , phenethyl group, 3-
phenylpropyl group, chlorobenzyl group, methylhensyl group, methoxybenzyl group, etc.), optionally substituted aryl groups (e.g. phenyl group, tolyl group, silyl group, chlorophenyl group, bromophenyl group, methoxyphenyl group, naphthyl group, etc.) ], -CONHCII□OR2 (Rg is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, etc.) (a
++az represents a hydrogen atom, a halogen atom (for example, a chlorine atom, a bromine atom, etc.), or an alkyl group having 1 to 4 carbon atoms (for example, a methyl group, an ethyl group, etc.). Moreover, specifically as the polymerizable double bond group,
-CI+2=CI+-1CHz□CII-C1lzCH
2=CII-NIICO-1C1!2FuCH-C112
-1NIIGO-C)12=C)1-50□-1C)I
! =CII-GO-1CH1C1! -0-CIl□・C
Examples include H-3-.

In the present invention, as a method for making the binder resin contain at least one functional group selected from the group of the curable functional groups, a method of introducing the functional group into the polymer by a polymer reaction, or a method of introducing the functional group into the polymer through a polymer reaction, or It can be obtained by a method of copolymerizing one or more monomers and a monomer corresponding to the repeating unit of general formula (+) or (Il) described above.

For polymer reactions, conventional methods for low molecule synthesis reactions can be used as they are; for example, the Chemical Society of Japan, "New Experimental Chemistry Course, Vol.
V), (published by Maruzen Co., Ltd.), written by Yoshiyu Iwakura and Keisuke Kurita [described in detail in the known literature cited in the review such as Reactive Polymer J.

On the other hand, examples of monomers containing the "functional group that performs photo and/or thermosetting reactions" include - copolymerization with monomers corresponding to repeating units of general formula (1) or (II) Examples include vinyl compounds containing such functional groups. For example, it is described in "Polymer Data Handbook [Basic Edition]" edited by the Society of Polymer Science and Technology, Baifukan (1986). Specifically, acrylic acid, α- and/or β-substituted acrylic acid (e.g. α-acetoxy form, α-acetoxymethyl form, α-(2-amino)methyl form, α-chloro form, α-bromo form, α -fluoro form, α-tributylsilyl form, α-cyano form, β-chloro form, β-pro form, α-chloro-β-methoxy form, α, β dichloro form, etc.), methacrylic acid, itaconic acid, itaconic acid Half esters, itaconic acid half amides, crotonic acid, 2-alkenylcarboxylic acids II (e.g. 2-pentenoic acid, 2-methyl-2-hexenoic acid, 2-octenoic acid, 4-methyl-2-hexenoic acid, 4 -ethyl-2-octenoic acid, etc.), maleic acid, maleic acid half esters, maleic acid half amides, vinyl benzene carboxylic acid, vinyl benzene carboxylic acid, vinyl sulfonic acid, vinyl phosphonic acid, vinyl group or allyl of dicarboxylic acids Examples include half-ester derivatives of these groups, ester derivatives of these carboxylic acids or sulfonic acids, and compounds containing the acidic group in a substituent of an amide derivative.

“The repeating unit (ii) containing the heat/photocurable functional group J will be exemplified.

tl+: -IL-C1h (bt: same below) C0
0C1lzCH=CII□ n, m: integer from 1 to 11 ii -6) b, b.

-(-CI! -C-?- n: Integer from 1 to 11 ii -7) bt bt 10CH-C→-1C00CHICHCI1200C-R ■ ii-4) b 1←CH2-C→- C00(C11 □) fiOCO (CI+2), -COO
-RRnee CH=CIhl-CIhCII=CIIzi
i -8) b Tobi■ 1l12-C-? - C00(CHl)CHCHz n: An integer from 1 to 4 Znee5-1-〇- An integer from 1 to 4 C0NHGHzOH b.

Total 11□-C→-- Nawate C0NII (CHt> -COOCHxcllcI!
zooC-R: 01 to C1 alkyl group n: Integer from 1 to 11 ii-19) 1,000CH-C1l-)- ii-20) Furthermore, the resin of the present invention has the general formula (1) or (I
Along with the monomer corresponding to the repeating unit of I> and the monomer containing any photo- and/or thermosetting functional group, other monomers other than these may be contained as a copolymerization component. .

For example, methacrylic esters, acrylic esters, crotonic esters, itaconic diesters (
Examples of the ester groups of these unsaturated carboxylic acids include methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group, octyl group, decyl group, dodecyl group, 2-hydroxyethyl group, and 2-chloroethyl group. ,2
-methoxydiethyl group, methoxymethyl group, ethoxymethyl group, 2,3-dihydroxypropyl group, 2- (N,
N-dimethylamino)ethyl group, 2-(N-morpholino)ethyl group, 2-furylethyl group, benzyl group, phenethyl group, cyclohexyl group, phenyl group, etc.), α-
Olefins, vinyl alkanoates or allyl esters, acrylonitrile, methacrylonitrinobevinyl ethers, acrylamides, methacrylamide, styrenes, heterocyclic vinyls (e.g. vinylpyrrolidone, vinylpyridine, vinylimidazole, vinylthiophene, vinylimidase) phosphorus, vinyl pyrazole, vinyl dioxane, vinyl giraffe, vinyl thiazole, vinyl oxazine, etc.).

In the present invention, a reaction accelerator may be added as necessary in order to accelerate the crosslinking reaction in the photosensitive layer especially when the photosensitive layer contains a photo- and/or thermosetting functional group. In the case of a reaction mode that forms a chemical bond between functional groups, for example, organic acids (acetic acid, propionic acid, acetic acid, benzenesulfonic acid,
crosslinking agents such as p-toluenesulfonic acid, etc.

As a crosslinking agent, specifically, Shinzo Yamashita and Tosuke Kaneko ed.
Compounds described in "Crosslinking Agent Handbook" published by Taiseisha (1981) and the like can be used. For example, commonly used crosslinking agents such as organic silanes, polyurethanes, and polyisocyanates, and curing agents such as epoxy resins and melamine resins can be used.

In the case of a polymerizable reaction mode, a polymerization initiator (peroxide, azobis-based compound, etc., preferably an azobis-based polymerization initiator), a monomer containing a polyfunctional polymerizable group (for example, vinyl Methacrylate, allyl methacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, divinylsuccinic acid ester, ester of divinyl succinate, diallyl succinate,
2-methyl vinyl methacrylate, divinylbenzene, etc.)
etc.

Furthermore, in the case of a resin containing a photocrosslinkable functional group, a sensitizer, a photopolymer monomer, etc. may be added. Specifically, the compounds cited in the review on photosensitive resins mentioned above can be used.

Further, in the present invention, when using a binder resin containing a thermosetting functional group, a thermosetting treatment is performed. This heat curing treatment can be performed by tightening the drying conditions during conventional photoreceptor production.

For example, the treatment may be performed at 60° C. to 120° C. for 5 minutes to 120 minutes). When using a resin containing a photocrosslinkable functional group, it is crosslinked by irradiation with electron beams, X-rays, ultraviolet rays, or plasma light after applying the photosensitive layer-forming material.
This may be done not only during drying, but also before or after drying, and the reaction is further accelerated by heating under the above drying conditions. When containing a thermally and/or photocurable functional group, when the above-mentioned reaction accelerator is used in combination, processing can be performed under milder conditions.

Inorganic photoconductive materials used in the present invention include zinc oxide,
Examples include titanium oxide, zinc sulfide, cadmium sulfide, cadmium carbonate, zinc selenide, cadmium selenide, tellurium selenide, lead sulfide, and the like.

Preferable examples include zinc oxide and titanium oxide. The total amount of binder resin used for the inorganic photoconductive material is 10 to 100 parts by weight, preferably 15 to 50 parts by weight, based on 100 parts by weight of the photoconductor.

In the present invention, various dyes can be used in combination as spectral sensitizers, if necessary. For example, Harumi Miyamoto: Hidehiko Takei: Imaging 1973 (No. 8) p. 12, C.
J. Young et al. RCA Review 15,4
69 (1954) Wataru Kiyota, Transactions of the Institute of Electrical Communication Engineers J6
3-C (No. 2), 97 (1980), Yuji Harasaki et al., Industrial Chemistry Magazine 66, 78 and 188 (1963),
Carbonium dyes, diphenylmethane dyes, triphenylmethane dyes, xanthine dyes, phthalein dyes, polymethine dyes (e.g. oxonol dyes, merocyanine dyes, cyanine dyes, logocyanine dyes, styryl dyes, etc.), phthalocyanine color S (which may contain metal), and the like.

More specifically, examples using mainly carbonium dyes, triphenylmethane dyes, xanthine dyes, and phthalein dyes include Japanese Patent Publication No. 51-452, Japanese Patent Application Laid-open No. 50-90334, and Japanese Patent Application Laid-open No. 50-90334. No. 50-114227,
JP 53-39130, JP 53-82353, U.S. Patent No. 3052540, U.S. Patent No. 40544
50, JP-A-57-16456, and the like.

oxonol dye, merocyanine dye, cyanine dye,
Polymethine dyes such as logcyanine dyes include F, M
, Hammer, rThe Cyanine Dy
es andRelated Compounds J
It is possible to use the pigments described in et al., and more specifically,
U.S. Patent No. 3,047,384, U.S. Patent No. 311,059
No. 1, U.S. Patent No. 3121008, U.S. Patent No. 312
No. 5447, U.S. Patent No. 3128179, U.S. Patent No. 3132942, U.S. Patent No. 3622317, British Patent No. 1226892, British Patent No. 1309274, British Patent No. 1405898, Japanese Patent Publication No. 4B-7814
Examples include dyes described in Japanese Patent Publication No. 55-18892.

Furthermore, as a polymethine dye that spectrally sensitizes the near-infrared to infrared light region with a long wavelength of 700 nm or more, JP-A-47-840
No., JP-A No. 47-44180, JP-A No. 51-4106
No. 1, JP-A-49-5034, JP-A-49-4512
No. 2, JP-A-5746245, JP-A-56-3514
No. 1, JP-A-57-157254, JP-A-61-26
No. 044, JP-A No. 61-27551, U.S. Patent No. 36
No. 19154, U.S. Pat. No. 4,175,956, rRes
-earch Disc1osureJ1982, 2
16, pp. 117-118.

The photoreceptor of the present invention is also excellent in that its performance does not easily vary depending on the sensitizing dye, even when various sensitizing dyes are used together.

Furthermore, if necessary, various conventionally known additives for electrophotographic photosensitive layers such as chemical sensitizers can be used in combination. For example, the above-mentioned review: Imaging groups (No. 8)
Electron-accepting compounds (e.g. halogens, benzoquinone, cranyl, acid anhydrides, organic carboxylic acids, etc.) cited in the review on page 12, Hiroshi Komon et al., "Recent Development and Practical Application of Photoconductive Materials and Photoreceptors", Vol. Chapters 4 to 6: Japanese Science Information ■Publishing Department (1
Polyaryl alkane compounds cited in the review of 986),
Examples include hindered phenol compounds and p-phenylenediamine compounds.

The amount of these various additives added is not particularly limited, but is usually 0.0001 to 2.0 parts by weight per 100 parts by weight of the photoconductor.
Parts by weight.

The thickness of the photoconductive layer is preferably 1 to 100 microns, particularly 10 to 50 microns.

In addition, when a photoconductive layer is used as a charge generation layer in a laminated photoreceptor consisting of a charge generation layer and a charge transport layer, the thickness of the charge generation layer is 0.01 to 1μ, particularly 0.05 to 0.5μ. suitable.

Charge transport materials for the laminated photoreceptor include polyvinylcarbazole, oxazole dyes, pyrazoline dyes, triphenylmethane dyes, and the like.

The thickness of the charge transport layer is 5 to 40 μm, particularly 10 to 3 μm.
0μ is suitable.

Typical resins used to form the insulating layer or charge transport layer include polystyrene resin, polyester resin, cellulose resin, polyether resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride vinyl oxide copolymer resin, Thermoplastic resins and curable resins such as polyacrylic resins, polyolefin resins, urethane resins, polyester resins, epoxy resins, melamine resins, and silicone resins are used as appropriate.

The photoconductive layer according to the invention can be provided on a conventionally known support. Generally speaking, the support of the electrophotographic photosensitive layer is preferably electrically conductive.As the electrically conductive support, for example, a base material such as metal, paper, or plastic sheet is impregnated with a low-resistance substance. The back side of the substrate (the side opposite to the side on which the photosensitive layer is provided) is coated with at least one layer for the purpose of preventing curling, etc., and the support mentioned above. Those with a water-resistant adhesive layer on the surface of the body, those with at least one pre-coated layer provided on the surface layer of the support as necessary, and those with a conductive plastic base coated with AZ, etc., on paper. You can use laminated ones, etc.

Specifically, examples of conductive substrates or conductive materials include:
Yukio Sakamoto, Electrophotography, 14, (No. 1), No. 2-11
Page (1975), Hiroyuki Moriga, "Introductory chemistry of special paper" Kobunshi Publishing (1975), M, F, 1loover+ J
, Macromol, Sci.

Chem, A-4(6), pp. 1327-1417 (
1970) etc. are used.

(Example) Examples of the present invention are illustrated below, but the content of the present invention is not limited thereto.

Example 1 and Comparative Examples A and B (Synthesis Example 1) 95 g of 2-chloro-6-methylphenyl methacrylate
After heating a mixed solution of 150 g of toluene and 50 g of isopropanol to a temperature of 80°C under a nitrogen stream, 44゛-azobis(4-cyanovaleric acid) (hereinafter abbreviated as A, B, C) was heated to a temperature of 80°C under a nitrogen stream.
, V) was added and reacted for 10 hours.

The weight average molecular weight of the obtained copolymer (P-1) was 6.5
00, the glass transition point was 40°C.

Structure of Resin (P-1) (Synthesis Example 2) After heating a mixed solution of 95 g of ethyl methacrylate, 5 g of acrylic acid, and 200 g of toluene to a temperature of 90°C under a nitrogen stream, 2.2゛-azobis(2, 6 g of 4-dimethylvaleronitrile) was added and reacted for 10 hours.

The weight average molecular weight of the obtained copolymer (A) was 7800,
The glass transition point was 45°C.

(Synthesis Example 3) After heating a mixed solution of 98 g of ethyl methacrylate, 2 g of acrylic acid, and 200 g of toluene to a temperature of 75°C under a nitrogen stream, 1.5 g of 2,2′-azobis(isobutyronitrile) was added. The reaction was allowed to proceed for 8 hours. The weight average molecular weight of the obtained copolymer (B) was 32,000, and the glass transition point was 45°C.

Example 1 40 g (as solid content) of the copolymer (P-1) produced in Synthesis Example 1, 200 g of zinc oxide, 0.02 g of heptamethine cyanine dye represented by the following structural formula, 0.05 g of phthalic anhydride A mixture of 300 g of toluene and 300 g of toluene was dispersed in a ball mill for 2 hours to prepare a photosensitive layer-forming product, which was applied to conductive-treated paper using a wire bar so that the dry adhesion amount was 18 g/nf, and the mixture was heated at 100°C. and dried for 30 seconds. Next, an electrophotographic light-sensitive material was prepared by leaving it for 24 hours in a dark place at 20° C. and 265% R11.

(Cyanine dye) Comparative Example A Same as Example 1 except that 40 g (as solid content) of the copolymer (A) produced in Synthesis Example 2 was used instead of the copolymer (P-1) used in Example 1. Comparative electrophotographic photoreceptor A was produced in the same manner.

Comparative Example B A comparative example was prepared in the same manner as in Example 1 except that 40 g (as solid content) of the copolymer (B) produced in Synthesis Example 3 was used instead of the copolymer (P-1) used in Example 1. Electrophotographic photoreceptor B was manufactured.

The film properties (surface smoothness), electrostatic properties, imaging properties, and imaging properties of these photosensitive materials were investigated under environmental conditions of 30° C. and 180% R11. Furthermore, when these photosensitive materials are used as original plates for offset masters, the photoconductive desensitization property (represented by the contact angle with water of the photoconductive layer after desensitization treatment) and printability (background smudge, The printing durability, etc.) were investigated.

Imageability and printability were determined using fully automatic plate making ELP404V (
Using a lithographic printing plate obtained by exposing and developing an image using the developer ELP-T (manufactured by Fuji Photo Film ■) and etching it with an etching process sensor using the desensitizing liquid ELPE, (The printing machine used was Hamadastar 800SX model manufactured by Hamadastar ■).

The above results are summarized in Table-1.

The implementation aspects of the evaluation items shown in Table 1 are as follows.

Note 1) Smoothness of photoconductive layer: The obtained photosensitive material was tested using a Beck smoothness tester (Kumagai Riko).
The smoothness (see/cc) was measured under the condition of an air volume of 11 cc.

Note 2) Electrostatic properties; After each photosensitive material was subjected to corona discharge at 6 kV for 20 seconds using a paper analyzer (Paper Analyzer 5P-428 model manufactured by Kawaguchi Electric) in a dark room at a temperature of 20°C and 165% R1+. , and the surface potential VIO at this time was measured. Then, the potential V after being left undisturbed for 90 seconds in the dark. The retention of the potential after dark decaying for 90 seconds, that is, the dark decay retention rate (DRR (2))
was determined by (Vqo/V+ o) x 100(χ). Also, Ko.

After the surface of the photoconductive layer is charged to -400V by electrostatic discharge, the surface of the photoconductive layer is irradiated with light from a gallium-aluminum arsenide semiconductor laser (oscillation wavelength: 830 nm), and the surface potential (V+) is attenuated to 1710V. Find the time taken to expose IE I/l. Calculate (erg/c).

The environmental conditions at the time of measurement were 20'C, 65% + 1) 1 (1)
and 30'C, 80% l? This was done with H(II).

Note 3) Imaging properties: After leaving each photosensitive material for one day and night under the following environmental conditions, each photosensitive material was charged at -6 KV and used as a light source with a gallium-aluminum-arsenide semiconductor laser (oscillation wavelength: 830 nm) with an output of 2.8 mW. ) on the surface of the photosensitive material, 64
After exposure under an irradiation dose of erg/c+il at a pitch of 25- and a scanning speed of 300 m/sec, the obtained image was developed and fixed using ELP-T (manufactured by Fuji Photo Film ■) as a liquid developer. The copied images (capri, image quality) were visually evaluated. 1. The environmental conditions at the time of the best image are 20°C, 65% RH (1), 30°C, 80% RH?
1 l (II).

Note 4) Contact angle with water: Each photosensitive material was passed once through an etching processor using a desensitizing treatment fiELP-E (manufactured by Fuji Photo Film) to desensitize the surface of the photoconductive layer. A drop of 2 μl of distilled water is placed on the glass, and the contact angle with the water formed is measured using a goniometer.

Note 5) Printing durability After making the plate in the same manner as for the imaging properties in Note 3) above, it was desensitized under the same conditions as Note 4) above, and this was used as an offset master to print on an offset printing machine (Oliver manufactured by Sakurai Seisakusho). 52 type) and using high-quality paper as the printing paper, it indicates the number of sheets that can be printed without causing background stains in the non-image areas of the printed matter and problems with the image quality of the image areas (the higher the number of sheets printed, the better the rigidity resistance. ).

Note 6) D, M, (ii! ii image density): Max value is indicated by the toner image density of the solid area (can be measured by Machess reflection density). As shown in Table 1, the photosensitive material of the present invention has the following properties: The smoothness and electrostatic properties of the photoconductive layer were good, and the actual copied image had no ground blur and the quality of the copied image was clear.

This means that the photoconductor and the binder resin are sufficiently adsorbed, and
This is presumed to be due to coating the particle surface.

For the same reason, even when used as an offset master original, the desensitizing treatment with the desensitizing treatment liquid progresses sufficiently, and the contact angle with water in the non-image area is as small as 15 degrees or less, making it sufficiently hydrophilic. It can be seen that When actually printing and observing the background smear on the printed matter, no background smudge was observed.

On the other hand, in Comparative Example A using a random copolymer which is a low molecular weight substance containing an acid component as a side chain of the random copolymer and also has ethyl methacrylate as a copolymerization component, the electrostatic charge at normal temperature and normal humidity is Looking at the characteristics and printing characteristics using the plate, it was possible to obtain copied images and printed images within a range that did not cause deterioration in image quality.

However, under high temperature and high humidity, the electrostatic properties deteriorate, and V...
D, R, R, and El/10 all decreased, and the actual copied image was not of sufficient image quality.

In addition, in Comparative Example B, which is the same [ethyl methacrylate/acrylic acid] copolymer as in Comparative Example A and has a large weight average molecular weight, the smoothness of the photoconductive layer is significantly deteriorated, and the electrostatic properties and In particular, R8R has deteriorated (E
The apparent high l/IQ value is due to low D and RoR). Even when used as an offset master plate, the contact angle with water in the non-image area after desensitization treatment was as large as 25 to 35 degrees and varied, and even in actual printing, scumming occurred from the beginning of printing. This is presumed to be due to an increase in the molecular weight of the binder resin, which causes adsorption to the photoconductor particles and aggregation between the particles, resulting in an adverse effect.

From the above, an electrophotographic photoreceptor that satisfies electrostatic properties and printability can be obtained only when the resin of the present invention is used.

Examples 2 to 23 As resins, copolymers shown in Table 2 were manufactured under the same manufacturing conditions as in Synthesis Example 1.

The weight average molecular weight of each of the resins obtained in Resin Examples P-2 to P-23 was 6.000 to 8.000.

Each photoreceptor was manufactured in the same manner as in Example 1, except that 40 g (as solid content) of each resin shown in Table 2 was used instead of 40 g of the copolymer (P-1) used in Example 1. death,
Each characteristic was measured in the same manner as in Example 1.

The surface smoothness of the photoconductive layer of each photoreceptor was 80 (SeC
/cc) or more, it was smooth. The results regarding electrostatic properties and imaging properties are also shown in Table 2.

All of the photosensitive materials of the present invention have excellent chargeability, dark charge retention, and photosensitivity, and the actual copied images are also produced at high temperatures and high humidity (30°C, 80°C).
Even under very severe conditions (%RH), it provided clear images without any occurrence of ground blur or fine line skipping.

Example 24 A mixed solution of 50 g of 2.6-dichlorophenyl methacrylate and 9 hupatol was heated to a temperature of 65° C. under a nitrogen stream, and then 0.9 g of azobisisobutyronitrile was added. 8 g was added and reacted for 8 hours. The weight average molecular weight of the obtained copolymer (P~24) was 7800, and the glass transition point was 36°C.

Structure L of Resin P-24 Same as Example 1 except that 40 g (as solid content) of the above copolymer (P-24) was used instead of 40 g of copolymer (P-1) used in Example 1. Each photoreceptor was manufactured in the same manner as in Example 1, and each characteristic was measured in the same manner as in Example 1.

The surface smoothness of the photoconductive layer of each photoreceptor is 80 (sec/
cc) and smooth. VIO; 740V%D
．． R6R; 3g%, Snake, 7. .

20 (erg/cn!>, (38℃, 80%RH
) The imaging performance under the environment was also good.

The photosensitive material of the present invention has excellent chargeability, dark charge retention, and photosensitivity, and the actual reproduced images can be maintained at high temperature and high humidity (30°C, 80% R).
Even under the harsh conditions of

Examples 25 to 30 Each copolymer was synthesized under the same conditions as in Example 24, except that the thioglycolic acid used in Example 24 was replaced with the compound shown in Table 3.

Table 3 H3 Each of these copolymers was treated under the same conditions as in Example 1 to produce each photosensitive material.

All of the photoreceptors of the present invention exhibited excellent characteristics.

Example 31 A copolymer with the following chemical structure (P-3
1) was used.

Resin (P-31) 40g of the resin, 200g of zinc oxide, 0 rose bengal
, 03g, Tetrabromophenol blue 0.02g
.

A mixture of 0.01 g of phthalic anhydride and 300 g of toluene was dispersed in a ball mill for 2 hours. Next, 10 g of allyl methacrylate and 0.5 g of 2.2'-azobisisobutyronitrile were added to this dispersion and dispersed in a ball mill for 10 minutes to prepare a photosensitive layer.

This was applied to conductive-treated paper using a wire bar so that the dry adhesion amount was 22 g/I, and dried at 80°C for 1 hour and then at 100°C for 30 minutes.
An electrophotographic photoreceptor was produced by leaving it for 24 hours under conditions of 165% IIH.

The electrostatic properties of the obtained photosensitive material were measured in the same manner as in Example 1. However, the light attenuation exposure amount (E, 7□) is after charging the photoconductive layer surface to -400V by corona discharge.
The surface of the photoconductive layer is irradiated with visible light at an illuminance of 2.0 lux, the time required for the surface potential (ν1°) to decay to 1/lo is determined, and from this the exposure I E I / I O (runx seconds) is determined. was calculated.

V+o: 560V, D, R, R=87χ, E+z
+o=8.31ux-sec.

Furthermore, this was made into ELP-T using a fully automatic plate making machine ELP404V.
When plate making was performed using the toner, the density of the obtained offset printing master plate was 1.0 or more and the image quality was clear. Further, when etching was performed and printed on a printing press, the printed matter after printing 7000 sheets had no fog in the non-image area and the image was clear. Also (30°C180%R
The electrostatic properties, imaging properties, and printability were similarly measured under the environmental conditions of H), but no difference was observed from room temperature.

Examples 32 to 37 In Example 31, except that the copolymer shown in Table 4 below was used instead of the resin of the present invention (P-31),
Each electrophotographic light-sensitive material was produced in the same manner as in Example 31.

Table 4 In Example 31, except that the copolymer shown in Table 5 below was used instead of the resin of the present invention (P-31),
Each photosensitive material was produced in the same manner as in Example 31. however,
The drying conditions after coating were 110'C for 12 hours.

Table 5 I (Weight Composition Ratio) When this was plate-made using the same apparatus as in Example 31, the density of the obtained offset printing master plate was 1.0 or more and the image quality was clear. Further, when etching was performed and printed on a printing press, the printed matter after printing 7000 sheets had clear image quality with no fogging.

Examples 38 and 39 These plates were made into plates using the same apparatus as in Example 31, and then etched and printed using a printing press. The density of the master plate for offset printing obtained after plate making is 1.1 or more,
Image quality was clear. Furthermore, the image quality of the printed matter after printing 5,000 sheets was clear and without blurring.

(Effects of the Invention) According to the present invention, it is possible to obtain an electrophotographic photoreceptor that is excellent in the smoothness of the photoconductive layer, electrostatic properties, imaging properties, as well as desensitization property and background smearing, and is particularly suitable for high temperature and high humidity. These excellent properties are maintained even under harsh conditions as described below.

Furthermore, the photosensitive material of the present invention has sufficiently high rigidity resistance to about several dozen sheets. When the binder resin further contains a copolymer component containing a heat-curable and/or photo-curable functional group, such rigidity resistance is further improved.

Claims (2)

[Claims] (1) In an electrophotographic photoreceptor having a photoconductive layer containing at least an inorganic photoconductive material and a binder resin, the binder resin has a weight average molecular weight of 1 x 10^3 to 5 x 10^4, A polymer containing the following (i) repeating unit as a polymerization component, and -PO only at one end of the polymer main chain.
_3H_2 group, -SO_3H group, -COOH group, ▲ Numerical formula, chemical formula, table, etc. ▼ group {R is a hydrocarbon group with 1 to 10 carbon atoms or -OR'(R' is a hydrocarbon group with 1 to 10 carbon atoms }, -SH group and phenolic O
An electrophotographic photoreceptor characterized by containing at least one resin formed by bonding at least one substituent of an acidic group and a cyclic acid anhydride-containing group of an H group. (i) At least one represented by formula (I) or formula (II)
30% or more of repeating units by weight Formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ Formula (II) (In the formula, X_1 and X_2 are each independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. , chlorine atom, bromine atom, -COY_1 or -COOY_2 (Y_1 and Y
_2 each represents a hydrocarbon group having 1 to 10 carbon atoms. However, both X_1 and X_2 do not represent hydrogen atoms. W_1 and W_2 each represent a direct bond or a connecting group having 1 to 4 connected atoms that connects -COO- and the benzene ring. ) (2) The electrophotography according to claim (1), wherein the resin contained in the binder resin is a resin that further contains the following repeating unit (ii) as a copolymerization component in addition to the repeating unit (i). Photoreceptor. (ii) 1 to 20% by weight of at least one repeating unit containing a thermally and/or photocurable functional group;