JP2655361B2 - Electrophotographic photoreceptor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly, to an electrophotographic photoreceptor excellent in electrostatic characteristics and moisture resistance. In particular, it relates to a CPC photosensitive member having excellent performance.

[Conventional technology]

The electrophotographic photosensitive member has various configurations in order to obtain predetermined characteristics or according to the type of an applied electrophotographic process.

Representative electrophotographic photoreceptors include a photoreceptor having a photoconductive layer formed on a support and a photoreceptor having an insulating layer on the surface, and are widely used.

Photoreceptors composed of a support and at least one photoconductive layer are used for image formation by the most common electrophotographic processes, i.e. charging, image exposure and development, and, if necessary, transfer.

Further, a method using an electrophotographic photosensitive member as an offset master for direct plate making has been widely used. In particular, in recent years, direct electrophotographic lithographic printing has become important as a method for printing high-quality printed matter with a print number of several hundreds to several thousands.

The binder resin used to form the photoconductive layer of the electrophotographic photoreceptor has excellent film forming properties of itself and the ability to disperse the photoconductive powder in the binder resin, and the formed recording material layer Has good adhesion to the substrate, and the photoconductive layer of the recording layer has excellent charging ability, low dark decay, large light decay, low pre-exposure fatigue, and changes in humidity during photography. It is necessary to have various electrostatic characteristics, such as a need to stably maintain these characteristics, and excellent imaging properties.

Furthermore, research on a lithographic printing original plate using an electrophotographic photoreceptor has been earnestly conducted, and a binder resin for a photoconductive layer having both electrostatic characteristics as an electrophotographic photoreceptor and printing characteristics as a printing original plate. is required.

However, conventionally known binder resins include, in particular, chargeability,
There are many problems in dark charge retention, electrostatic characteristics such as photosensitivity, and smoothness of the photoconductive layer.

In order to solve these problems, a low molecular weight resin containing 0.05 to 10% by weight of a copolymer component containing an acidic group as a binder resin in the side chain of the polymer or an acidic group is added to the terminal of the polymer main chain. The use of a low molecular weight resin (w10 ³ to 10 ⁴ ) that binds to the photoconductive layer improves the smoothness and electrostatic characteristics of the photoconductive layer and obtains an image quality free from background contamination. And JP-A-64-70761 and JP-A-Hei 2
-67563.

Further, as a binder resin, a resin containing a polymer component containing an acidic group in a side chain of a copolymer or bonding to a terminal of a polymer main chain and containing a heat and / or photo-curable functional group JP-A-1-100554, Japanese Patent Application No. 63-39690 discloses that a resin containing an acidic group in a side chain of a copolymer or a resin binding to an end of a polymer main chain is used in combination with a crosslinking agent. The techniques are disclosed in JP-A-1-102573 and JP-A-2-874, respectively. Further, a low molecular weight compound (weight average molecular weight of 10 ³ to 10 ⁴ ) is combined with a high molecular weight (weight average molecular weight of 10 ⁴ or more) resin. Techniques used in combination are disclosed in JP-A-64-564, JP-A-63-220149 and JP-A-63-220.
No. 148, JP-A-1-280761, JP-A-1-116664 and JP-A-1
JP-A-169455 discloses a technique using such a low molecular weight compound in combination with a heat and / or photocurable resin, and JP-A 1-211766 and 2-34859, a technique using such a low molecular weight substance in combination with a comb-type polymer. Are disclosed in JP-A-2-53064 and JP-A-2-56558.
And Japanese Patent Application No. 63-254786, respectively.
According to these techniques, the film strength of the photoconductive layer is further sufficiently leveled and the mechanical strength is increased without impairing the above properties due to the use of a resin containing an acidic group at a side chain or at a terminal. Have been.

(Problems to be Solved by the Invention) However, even if these resins are used, it is still insufficient to maintain stable performance when the environment fluctuates remarkably from high temperature and high humidity to low temperature and low humidity. Was. In particular, in the scanning exposure method using a semiconductor laser beam, the exposure time is longer and the exposure intensity is limited as compared with the conventional simultaneous exposure method using visible light. Higher performance is required for light sensitivity.

Furthermore, in the electrophotographic lithographic printing plate precursor, when the scanning exposure method using the semiconductor laser light is adopted, when the conventional photoconductor is actually tested, the above electrostatic characteristics are unsatisfactory, In particular, the difference between E _1/2 and E _1/10 is large, the tone of the copied image becomes soft, and it becomes difficult to further reduce the residual potential after exposure, and the fog of the copied image becomes remarkable, In addition, even when printing is performed as an offset master, a serious problem such as sticking traces of a printed original appears on a printed material has appeared.

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

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor having stable and good electrostatic characteristics and having a clear and high-quality image even when the environment at the time of forming a copy image fluctuates such as low temperature and low humidity or high temperature and high humidity. To provide.

Another object of the present invention is to provide a CPC electrophotographic photoreceptor having excellent electrostatic characteristics and low environmental dependency.

Another object of the present invention is to provide an electrophotographic photosensitive member effective for a scanning exposure method using a semiconductor laser beam.

A further object of the present invention is to provide an electrophotographic lithographic printing plate precursor having excellent electrostatic properties (particularly dark charge retention and light sensitivity),
By providing a lithographic printing original plate that reproduces a copy image that is faithful to the original image and that does not generate spotted background stains as well as uniform background stains on the printed material and that has excellent printing durability is there.

(Means for Solving the Problems) The object is to provide an electrophotographic photoreceptor having a photoconductive layer containing at least an inorganic photoconductor and a binder resin, wherein the binder resin is at least one of the following resins [A]: It has been found that this can be achieved by an electrophotographic photoreceptor characterized by comprising one kind and at least one kind of resin [B].

Resin (A); an average molecular weight of ^{1 × 10 3 ~2 × 10 4} , -PO 3 H 2 group,
-COOH group, -SO ₃ H group, a phenolic OH group, R represents a hydrocarbon group or an -OR 'group (R' is a hydrocarbon group) and A comprises at least one polymer component containing at least one acidic group selected from cyclic acid anhydride-containing groups. A resin containing an AB block copolymer composed of a block and a B block containing at least a polymer component represented by the following general formula (I).

General formula (I) (In the formula (I), R ₁ represents a hydrocarbon group.) Binder resin [B]: at least one of the polymer components represented by the following general formulas (IVa) and (IVb) and- COOH group, -PO ₃ H ₂ group, -S
O ₃ H group, -OH group, (R ₀ represents the same content as R above), at least one polymer component containing at least one component containing at least one polar group selected from the group consisting of a —CHO group and an acid anhydride-containing group. A monofunctional macromonomer (MB) having a weight-average molecular weight of 2 × 10 ⁴ or less which is obtained by bonding a polymerizable double bond group represented by the following general formula (III) to only one end of a polymer main chain containing And a monomer represented by the following general formula (V): a weight average molecular weight of at least 5 × 10 ⁴ to 1 × 1
Copolymers of 0 ^6.

General formula (III) In the formula (III), X ₀ represents —COO—, —OCO—, —CH ₂ OCO—,
_{-CH 2 COO -, - O -} , - SO 2 -, - CO -, - CONHCOO-,
−CONHCONH−, Or Wherein R ₃₁ represents a hydrogen atom or a hydrocarbon group.

c ₁ and c ₂ may be the same or different, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, -COO-Z
₄ or —COO—Z ₄ via a hydrocarbon (Z ₄ represents a hydrogen atom or a hydrocarbon group which may be substituted).

General formula (IVa) General formula (IV b) Wherein (IV a) or (IV b), X ₁ represents the same content as X ₀ in formula (III). Q ₁ represents an aliphatic group having 1 to 18 carbon atoms or an aromatic group having 6 to 12 carbon atoms. d ₁ and d ₂ may be the same or different from each other, and represent the same contents as c ₁ and c _{2 in} formula (III).

Q ₀ is -CN, -CONH ₂ or The expressed, Y represents a hydrogen atom, a halogen atom, an alkoxy group or -COOZ ₅ (Z ₅ represents an alkyl group, an aralkyl group or an aryl group).

General formula (V) Wherein (V), X ₂ represents a X ₁ same contents as in formula (IV a), Q ₂ represents Q ₁ same contents as in formula (IV a).
e ₁ and e ₂ may be the same or different and represent the same contents as c ₁ and c _{2 in} formula (III).

The binder resin of the present invention is a resin comprising an AB block copolymer of the A block containing the specific acidic group-containing component and the B block containing the polymer component represented by the above formula (I). [A] and at least a high molecular weight resin [B] composed of a graft copolymer containing at least a monofunctional macromonomer (MB) and a monomer represented by the general formula (V).

Furthermore, as the low molecular weight resin [A], 2-position represented by the following general formulas (Ia) and (Ib), and / or
Or a resin [A] containing a methacrylate component having a specific substituent and an acidic group component containing a benzene ring having a specific substituent at the 2- and 6-positions or an unsubstituted naphthalene ring; It is particularly preferable that the resin is a resin [A '].

General formula (Ia) General formula (Ib) [In formula (Ia) or (Ib), M ₁ and M ₂ are independently of each other;
Each represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a chlorine atom, a bromine atom, -COZ ₂ or -COOZ ₂ (Z ₂ are each carbon atoms 1
~ 10 hydrocarbon groups). However, M ₁ and M ₂ are never both represent a hydrogen atom.

L ₁ and L ₂ each connect -COO- and a benzene ring,
It represents a single bond or a linking group having 1 to 4 linking atoms. The resin [A] used in the present invention is an AB block copolymer, and the A block is composed of at least one polymerization component containing at least one selected from the above-described specific acidic groups, and a B block. Comprises a polymer component containing at least one methacrylate component represented by the formula (I), and has a weight average molecular weight of 1 ×
It is characterized in that it is 10 ^{3 to} 2 × 10 ⁴ .

Among the acidic group-containing binder resins known to improve the smoothness and electrostatic properties of the photoconductive layer described above, those using a low-molecular-weight compound have an acidic group-containing polymer component randomly present in the polymer main chain. Or a resin having an acidic group bonded only to one terminal of the polymer main chain.

On the other hand, the resin [A] used in the binder resin of the present invention binds only to the terminal of the polymer main chain even if the acidic group contained in the resin is randomly present in the polymer main chain. However, the copolymer is not specified, but is further specified so as to exist as a block in the polymer main chain.

The copolymer according to the present invention, while the region of the portion of the acidic group unevenly distributed to one side portion of either one of the main chain of the polymer is sufficiently adsorbed to the stoichiometric defect of the inorganic photoconductor, It is presumed that the other block portions constituting the polymer main chain cover the surface of the photoconductor slowly and sufficiently. Due to its action mechanism, the copolymer according to the present invention has a sufficient adsorption area even if the stoichiometric defect of the inorganic photoconductor fluctuates somewhat, so that the inorganic photoconductor and the resin [A According to the present invention, it is inferred that according to the present invention, the photoconductor traps can be more sufficiently compensated and the humidity characteristics can be improved more excellently than the conventionally known acidic group-containing resin, while the light characteristics can be improved. The conductor is sufficiently dispersed,
It has been found that aggregation is suppressed.

The resin [B] does not hinder the high performance of the electrophotographic properties due to the use of the resin [A] at all, and the resin [A] alone provides sufficient mechanical strength of the photoconductive layer, which is insufficient. It has been found that a sufficiently good imaging performance can be obtained even when the environment fluctuates as described above or a low output laser beam is used.

This is a resin [A] as a binder resin for the inorganic photoconductor.
And the resin [B] by specifying the weight average molecular weight of the resin and the content and bonding position of the acidic group in the resin,
It is presumed that the strength of the interaction between the inorganic photoconductor and the resin was appropriately changed. That is, the resin [A] having a stronger interaction selectively and appropriately adsorbs to the inorganic photoconductor, while the resin [B] having a weaker interaction than the resin [A] inhibits the electrophotographic properties. It is presumed that by gently interacting with the inorganic photoconductor to such an extent that both the electrophotographic characteristics and the mechanical strength were remarkably improved as described above.

Further, when the resin [A '] is used, the electrophotographic properties (especially V ₁₀ , DRR, E _1/10 ) are higher than those of the resin [A].
Can be improved.

Further, in the present invention, the smoothness of the photoconductive layer surface becomes smooth. On the other hand, when a photoconductor having a rough surface of the photoconductive layer is used as the electrophotographic lithographic printing plate precursor, the dispersion state of the zinc oxide particles as the photoconductor and the binder resin is not appropriate, and an aggregate exists. Since the photoconductive layer is formed in the state, even if the desensitizing treatment with the desensitizing solution is performed, the non-image portion is not sufficiently and sufficiently hydrophilized, causing adhesion of the printing ink during printing, and as a result, The background stain on the non-image portion of the printed matter occurs.

When the resin of the present invention is used, the interaction between the adsorption and coating of the photoconductor and the binder resin is appropriately performed, and the film strength of the photoconductive layer is maintained.

Even when only the low molecular weight resin [A] in the present invention is used as the binder resin, the photoconductor and the binder resin are sufficiently adsorbed, and the surface of the particles can be coated. It has good electrostatic characteristics and an image quality free from background contamination. Further, it has sufficient film strength as a CPC photoreceptor or an offset original plate having thousands of printed sheets. However, by coexisting the resin [B] as in the present invention, the mechanical strength of the photoconductive layer which is still insufficient with the resin [A] alone without further alienating the function of the resin [A] is further improved. I was able to. Accordingly, the photoreceptor of the present invention has excellent electrostatic characteristics even when environmental conditions fluctuate, has sufficient film strength, and is subjected to severe printing conditions (for example,
Even when the printing pressure is increased with a large printing press), it is possible to print more than 10,000 sheets.

Further, the resin [B] has -PO at only one end of the polymer main chain.
₃ H ₂ group, -SO ₃ H group, -COOH group, -OH group, -SH group and (R ₀ 'represents the same content as R) and a graft copolymer further comprising at least one polar group selected from cyclic acid anhydride-containing groups (hereinafter, this high-molecular-weight product is preferably a resin [B' ]).

When the resin [B '] is used, the electrostatic characteristics, particularly DRR and E _1/10, are improved, and the excellent characteristics obtained by using the resin [A] are not hindered at all. It is preferable because there is almost no change even in environmental changes such as low temperature and low humidity. Further, the film strength is further improved, and the printing durability is improved.

Spectral sensitizing dyes that are usually used to maintain photosensitivity in the visible light to infrared light regions are those whose spectral sensitizing function sufficiently functions by being adsorbed to a photoconductor, and are therefore common to the present invention. It is assumed that the binder resin containing the polymer appropriately interacts with the photoconductor without inhibiting the adsorption of the spectral sensitizing dye. This effect was particularly remarkable with cyanine dyes or phthalocyanine pigments, which are particularly effective as dyes for spectral sensitization of near infrared to infrared light.

In the block copolymer [A], the polymer component amount of the specific acidic group-containing component is preferably 0.5 to 20 parts by weight, more preferably 3 to 15 parts by weight per 100 parts by weight of the copolymer [A]. It is contained in.

The amount of the methacrylate component represented by the formula (I) in the block portion (B block) containing the methacrylate component represented by the general formula (I) is calculated based on the total weight of the block.
Preferably from 30% to 100% by weight, more preferably from 50 to 1%
00% by weight. The weight average molecular weight of the copolymer [A] is 1
× 10 ³ to 1 × 10 ⁴ , preferably 3 × 10 ³ to 1 × 10 ⁴ .

When the molecular weight of the resin [A] is less than 1 × 10 ³ , the film-forming ability is reduced and sufficient film strength cannot be maintained. When the molecular weight is more than 2 × 10 ⁴ , the effect of the resin [A] of the present invention may be reduced. And the electronic properties are about the same as those of conventionally known resins.

When the content of the acidic group in the binder resin [A] is less than 0.5% by weight, the initial potential is low and a sufficient image density cannot be obtained. When the content of the acidic group is more than 20% by weight,
It is not preferable because the dispersibility is reduced, the film smoothness and the high humidity property of the electrophotographic properties are reduced, and furthermore, the background smear increases when used as an offset master.

The glass transition point of the resin [A] is preferably in the range of -10C to 100C, more preferably -5C to 85C.

The polymerization component containing a specific acidic group constituting the A block of the AB block copolymer (resin [A]) of the present invention will be described more specifically.

The acidic group, -PO ₃ H ₂ group, -COOH group, -SO ₃ H group,
Phenolic OH group, {R is a hydrocarbon group or -OR 'group (R' is a hydrocarbon group),} and include cyclic acid anhydride-containing group, preferably, -COOH group, -SO ₃ H groups, phenolic OH groups ,as well as It is.

In the above, R represents a hydrocarbon group or an -OR 'group (R' represents a hydrocarbon group), and R and R 'are preferably an aliphatic group having 1 to 22 carbon atoms (for example, a methyl group, an ethyl group, Propyl, butyl, hexyl, octyl, decyl, dodecyl, octadecyl, 2-chloroethyl, 2-methoxyethyl, 3-ethoxypropyl,
Allyl group, crotonyl group, butenyl group, cyclohexyl group, benzyl group, phenethyl group, 3-phenylpropyl group, methylbenzyl group, chlorobenzyl group, fluorobenzyl group, methoxybenzyl group, etc.), or an optionally substituted aryl group (For example, phenyl, tolyl, ethylphenyl, propylphenyl, chlorophenyl,
Fluorophenyl group, bromophenyl group, chloro-methyl-phenyl group, dichlorophenyl group, methoxyphenyl group, cyanophenyl group, acetamidophenyl group, acetylphenyl group, butoxyphenyl group, etc.).

Examples of the phenolic OH group include methacrylic esters or amides containing a hydroxyphenol or hydroxyphenyl group as a substituent.

Further, the cyclic acid anhydride-containing group is a group containing at least one cyclic acid anhydride, and examples of the cyclic acid anhydride contained include aliphatic dicarboxylic anhydride and aromatic dicarboxylic anhydride. Can be

Examples of the aliphatic dicarboxylic anhydride include a succinic anhydride ring, a glutaconic anhydride ring, a maleic anhydride ring,
Cyclopentane-1,2-dicarboxylic anhydride ring, cyclohexane-1,2-dicarboxylic anhydride ring, cyclohexene-1,2-dicarboxylic anhydride ring, 2,3-picyclo [2.2.
2] octanedicarboxylic anhydride rings and the like, and these rings are substituted with, for example, halogen atoms such as chlorine atom and bromine atom, and alkyl groups such as methyl group, ethyl group, butyl group and hexyl group. Is also good.

Examples of the aromatic dicarboxylic anhydride include a phthalic anhydride ring, a naphthalene-dicarboxylic anhydride ring, a pyridine-dicarboxylic anhydride ring, a thiophene-dicarboxylic anhydride ring, and the like. Is, for example, a chlorine atom, a halogen atom such as a bromine atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a hydroxyl group, a cyano group, a nitro group, an alkoxycarbonyl group (for the alkoxy group, for example, Methoxy group, ethoxy group, etc.) may be substituted.

Examples of the above-mentioned “polymer component containing a specific acidic group” include a polymer component constituting the B block component in the resin [A] of the present invention, that is, a methacrylate component represented by the general formula (I), and the like. Any vinyl compound containing the acidic group, which copolymerizes with the corresponding vinyl compound, can be used.

For example, vinyl compounds described in “Polymer Data Handbook [Basic Edition]” edited by The Society of Polymer Science, Baifukan (1986) and the like can be used. Specifically, acrylic acid, α and / or β Substituted acrylic acid (for example, α-acetoxy form, α-acetoxymethyl form, α- (2-amino)
Ethyl form, α-chloro form, α-bromo form, α-fluoro form, α-tributylsilyl form, α-cyano form, β-chloro form, β-bromo form, α-chloro-β-methoxy form,
α, β-dichloro form), methacrylic acid, itaconic acid,
Itaconic acid half esters, itaconic acid half amides, crotonic acid, 2-alkenylcarboxylic acids (eg, 2-pentenoic acid, 2-methyl-2-hexenoic acid, 2-octenoic acid, 4-methyl-2-hexenoic acid, 4-ethyl-2-octenoic acid), maleic acid, maleic acid half esters,
Maleic acid semi-amides, vinyl benzene carboxylic acid, vinyl benzene sulfonic acid, vinyl sulfonic acid, vinyl phosphoic acid, vinyl or allyl group half-ester derivatives of dicarboxylic acids, and ester or amide derivatives of these carboxylic or sulfonic acids And a compound containing the acidic group in the substituent.

The following are specific examples of these compounds. However, in each of the following examples, a is -H,-
_{CH 3, -Cl, -Br, -CN} -, - CH 2 COOCH 3 or -CH ₂ COOH
Are shown, b represents -H or -CH _3, n is an integer of 2 to 18, m represents an integer of 1 to 12, l is an integer of 1-4.

(M may be the same or different) (a-15) CH ₂ CHCH—CH ₂ OCO (CH ₂ ) mCOOH (a-16) CH ₂ CHCHCH _{2 l} COOH Two or more types of polymerization components containing the specific acidic group as described above may be contained in the A block, and in that case, the two or more types of acidic group-containing components may be randomly copolymerized in the A block. It may be contained in any form of block copolymerization.

Further, the component not containing the acidic group may be contained in the A block, and examples of the component include components represented by the general formula (I) or (II). The content of the acidic group-free component is preferably 0 to 50% by weight, more preferably 0 to 20% by weight in the A block, and most preferably, the acidic group-free component is not contained in the A block. .

Next, the polymerization component constituting the B block component in the AB block copolymer [A] will be described in detail.

The B block component contains at least a methacrylate component represented by the general formula (I), and the methacrylate component of the formula (I) is preferably 30 to 100% by weight, more preferably 50 to 100% by weight in the B block component. Contained.

In the repeating unit represented by the general formula (I), the hydrocarbon group of R ₁ may be substituted.

R ₁ preferably represents an optionally substituted hydrocarbon group having 1 to 18 carbon atoms. As the substituent, any substituent may be used as long as it is a substituent other than the acidic group contained in the polymerization component constituting the A block of the AB block copolymer. For example, a halogen atom (for example, a fluorine atom, a chlorine atom, bromine _{atom) -O-Z 1, -COO-} Z 1, -OCO-Z 1, (Z 1 is
Represents an alkyl group having 1 to 22 carbon atoms, for example, a methyl group,
Substituents such as ethyl, propyl, butyl, hexyl, octyl, decyl, dodecyl, hexadecyl and octadecyl). Preferred hydrocarbon groups include alkyl groups having 1 to 18 carbon atoms which may be substituted (for example, methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group, octyl group,
Decyl group, dodecyl group, hexadecyl group, octadecyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group, 2-
A methoxyethyl group, a 3-bromopropyl group and the like, and an optionally substituted alkenyl group having 4 to 18 carbon atoms (for example, 2-
Methyl-2-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group, 1-pentenyl group, 1-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group, etc. ), An optionally substituted aralkyl group having 7 to 12 carbon atoms (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group,
-Naphthylethyl group, chlorobenzyl group, bromobenzyl group, methylbenzyl group, ethylbenzyl group, methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group, etc.), an optionally substituted alicyclic group having 5 to 8 carbon atoms (Eg, cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, etc.) or an optionally substituted aromatic group having 6 to 12 carbon atoms (eg, phenyl group, naphthyl group, tolyl group, xylyl group, propyl Phenyl group,
Butylphenyl, octylphenyl, dodecylphenyl, methoxyphenyl, ethoxyphenyl, butoxyphenyl, decyloxyphenyl, chlorophenyl, dichlorophenyl, bromophenyl, cyanophenyl, acetylphenyl, methoxycarbonylphenyl Group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group, acetamidophenyl group,
Propioamidophenyl group, dodecylylamidophenyl group, etc.).

In the hydrocarbon group of R _1, preferably when R ₁ is an aliphatic group, preferably not less than 60% by weight of the component represented a hydrocarbon group having 1 to 5 carbon atoms in formula (I) .

Further, in the resin [A], a part or all of the repeating unit represented by the general formula (I) constituting the B block component is a repeating unit represented by the following general formula (Ia) and / or (Ib). It is preferred that Therefore, at least one repeating unit selected from the following general formulas (Ia) and (Ib) in the B block component accounts for 30% by weight in the other block.
As described above, it is particularly preferable to contain 50 to 100% by weight.

General formula (Ia) General formula (Ib) [In formula (Ia) or (Ib), M ₁ and M ₂ are independently of each other;
Each represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a chlorine atom, a bromine atom -COZ ₂ or -COOZ ₂ (Z ₂ each having a carbon number 1 to 1
0 represents a hydrocarbon group). However, M ₁ and M ₂ are never both represent a hydrogen atom.

L ₁ and L ₂ respectively couples -COO- and the benzene ring, represents a single crystal or a linking atoms 1-4 linking groups. By containing the repeating unit represented by the formula (Ia) and / or (Ib) in a B block containing no acidic group, the electrophotographic properties (particularly, V ₁₀ , DRR, E
_1/10 ) improvement can be achieved.

Although the reason for this is unknown, one reason is that the ester component of methacrylate, a planar benzene ring having a substituent at the ortho-position, or the effect of a naphthalene ring at the zinc oxide interface in the film. It is considered that the arrangement of these polymer molecular chains is properly performed.

In the formula (Ia), as preferred M ₁ and M ₂ , in addition to a hydrogen atom, a chlorine atom and a bromine atom, as a preferred hydrocarbon group, an alkyl group having 1 to 4 carbon atoms (eg, a methyl group, an ethyl group, A propyl group, a butyl group, etc., an aralkyl group having 7 to 9 carbon atoms (for example, benzyl group, phenethyl group, 3-phenylpropyl group, chlorobenzyl group,
A dichlorobenzyl group, a bromobenzyl group, a methylbenzyl group, a methoxybenzyl group, a chloro-methyl-benzyl group and the like; and an aryl group (for example, a phenyl group, a tolyl group,
Silyl group, bromophenyl group, methoxyphenyl group, chlorophenyl group, dichlorophenyl group, etc.), and -CO
Z ₂ and —COOZ ₂ (preferable Z _{2 can} include those described as preferable hydrocarbon groups above). However, M ₁ and M ₂ are never both represent a hydrogen atom.

In the formula (Ia), L ₁ is a direct bond or —CH _{2 n1} (n ₁ represents an integer of ₁ to 3), —CH ₂ CH ₂ OCO—, (CH ₂ O) _n2 (n ₂ represents an integer of 1 or _{2), - CH 2 CH 2} O- number such linking atom, such as 1
Represents 4 linking groups.

L ₂ in the formula (I b) is the same meaning as L _1.

Specific examples of the repeating unit represented by the formula (Ia) or (Ib), which is preferably used in the B block of the resin [A] of the present invention, are shown below. However, the scope of the present invention is:
It is not limited to these.

In the B block constituted separately from the component A block from the polymerization component containing the specific acidic group, the repeating unit represented by the formula (I) {preferably (Ia) or (Ib)} is Two or more kinds may be contained, and other polymerization components other than these may be contained. When two or more polymerization components are contained in the B block containing no acidic group, the AB block copolymer component is contained in the B block in any mode of random copolymerization or block copolymerization. However, it is preferable to be contained at random.

Other polymerization components which can be contained in the B block together with the polymerization components selected from the repeating units represented by the above formulas (I), (Ia) and / or (Ib) are components copolymerized with these. Any may be used.

For example, a repeating unit represented by the following general formula (II) can be mentioned.

General formula (II) [In the formula (II), T is -COO-, -COO-, CH _{2 m1} OCO
−, CH _{2 m2} COO−, −O−, SO ₂ −, −CONHCOO−, −CONHCONH−, or And m ₁ and m ₂ each represent an integer of 1 to 2;
₃ represents the same contents as R ₁ in the formula (I). R ₂ is the same meaning as R ₁ in formula (I).

a ₁ and a ₂ may be the same or different from each other, and each is a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group having 1 to 8 carbon atoms, -COO-Z ₃ or a hydrocarbon group having 1 to 8 carbon atoms. Represents —COO—Z ₃ (Z ₃ represents a hydrocarbon group having 1 to 18 carbon atoms). More preferably, a ₁ and a ₂ may be the same or different from each other, and represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms (eg, a methyl group, an ethyl group, a propyl group, etc.), —COO—Z ₃ or _{-CH 2 COO-Z 3 (Z} 3 more preferably represents an alkyl or alkenyl group having 1 to 18 carbon atoms, e.g., methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl Group, dodecyl group,
Tridecyl group, tetradecyl group, hexadecyl group, octadecyl group, pentenyl group, hexenyl group, octenyl group, decenyl group and the like, and these alkyl group and alkenyl group have the same substituents as those described for R ₁ above. ).

As a monomer constituting a repeating unit other than these,
Further, styrenes (for example, styrene, vinyltoluene, chlorostyrene, bromostyrene, dichlorostyrene, vinylphenol, methoxystyrene, chloromethylstyrene, methoxymethylstyrene, acetoxystyrene,
Methoxycarbonylstyrene, methylcarbamoylstyrene, etc.), acrylonitrile, methacrylonitrile,
Acrolein, methacrolein, vinyl group-containing heterocyclic compounds (eg, N-vinylpyrrolidone, vinylpyridine,
Vinyl imidazole, vinyl thiophene, etc.), acrylamide, methacrylamide and the like.
These other copolymer components are not limited to these.

The AB block copolymer [A] of the present invention can be produced by a conventionally known polymerization reaction method. In particular,
In the monomer corresponding to the polymer component containing the specific acidic group, the acidic group is previously protected as a functional group, and an organometallic compound (eg, alkyl lithiums, lithium diisopropylamide, alkyl magnesium halides, etc.) or Protecting acidic groups after synthesizing AB block copolymer by known so-called living polymerization reaction such as ionic polymerization reaction by hydrogen iodide / iodine system, photopolymerization reaction using porphyrin metal complex as catalyst or group transfer polymerization reaction The deprotection reaction is performed by a hydrolysis reaction, a hydrogenolysis reaction, an oxidative decomposition reaction, a photodecomposition reaction, or the like to form an acidic group. One example is shown in the following reaction scheme (1).

For example, P. Lutz, P. Masson etal, Polym. Bull. 12 .
(1984), BCAnderson, GDAndrews etal, Macromolecu
les, 14 , 1601, (1981), K. Hatada, K. Ute. et al., Polym. J. 1
7, 977 (1985), 18, 1037 (1986), the right hand Koichi, Koichi Hatada, polymer processing, 36, 366 (1987), Higashimura Satoshinobe, Mitsuo Sawamoto, polymer Collected Papers, 46, 189 (1989), M.Kuroki, T.Aida,
J. Am. Chem. Soc. 109 , 4737 (1987), Takuzo Aida, Shohei Inoue, Synthetic Organic Chemistry, 43 , 300 (1985), DYSogah, WRHe
Macromolecules, 20 , 1473 (1987), etc. can be easily synthesized.

Further, the AB block copolymer [A] can also be synthesized by a photoiniferter polymerization method using a monomer without protecting the acidic group and using a dithiocarbamate compound as an initiator. For example, Takayuki Otsu, polymeric, 37, 248 (19
88), Shunichi Yarimori, Ryuichi Otsu, Polym.Rep.Jap. 37. 3508 (1
988), JP-A-64-111, JP-A-64-26619, and the like.

Further, the protecting group for protecting the specific acidic group of the present invention and the elimination of the protecting group (deprotection reaction) can be easily carried out by utilizing conventionally known knowledge. For example, various descriptions are given in the above cited references, and furthermore, Yoshio Iwakura, Keisuke Kurita, “Reactive Polymers” published by Kodansha (1977)
TWGreene, "Protective Groups in Organic Sy
nthesis ", John Wiley & Sons (1981), JFW McOmi
e, `` Protective Groups in Organic Chemistry '' Plenum
Press, (1973) and the like can be carried out by appropriately selecting a method described in detail.

In the resin [A], the amount of the specific acidic group-containing polymer component in the AB block copolymer is 0.5 to 20% by weight, preferably 3 to 20% by weight in 100 parts by weight of the resin [A].
15% by weight. The weight average molecular weight of the resin [A] is preferably 3 × 10 ³ to 1 × 10 ⁴ .

On the other hand, the weight average molecular weight of the resin [B] is 5 × 10 ⁴ -1 × 1
0 ^6, preferably from ^{8 × 10 4 ~5 × 10 5} . The proportion of the monofunctional macromonomer (MB) in the polymer ranges from 1 to
It is preferably 70% by weight, and the proportion of the monomer represented by the general formula (V) in the polymer is preferably 30 to 99% by weight.

When the polar group is bonded to the terminal of the main chain of the copolymer, the proportion of the polar group in the copolymer is 0.1 to 10% by weight, preferably 0.2 to 5% by weight.

The glass transition point of the resin [B] is preferably 0 ° C to 110 ° C.
° C, more preferably 20 ° C to 90 ° C.

When the molecular weight of the binder resin [B] is smaller than 5 × 10 ⁴ , the film strength cannot be sufficiently maintained. On the other hand, when the molecular weight is larger than 1 × 10 ⁶ , the dispersibility is reduced and the film smoothness is deteriorated. The image quality of the image (particularly, the reproducibility of fine lines and characters is deteriorated) deteriorates, and furthermore, when used as an offset master, the background smear becomes remarkable.

Monofunctional macromonomer (M
If the content of B) is less than 1.0% by weight, the electrophotographic properties (particularly, dark decay rate and light sensitivity) are reduced, and the fluctuation of the electrophotographic properties under environmental conditions is particularly near infrared to infrared spectral sensitization. In combination with a dye, it increases. It is considered that this is because the composition of the macromonomer serving as the graft portion becomes small, resulting in almost the same composition as the conventional homopolymer or random copolymer.

On the other hand, when the content of the monofunctional macromonomer (MB) exceeds 70%, the copolymerizability between the monomer corresponding to the other copolymerization component and the macromonomer according to the present invention becomes insufficient, and as a binder resin, Even if used, sufficient electrophotographic characteristics cannot be obtained.

In the resin [B] of the present invention, the monofunctional macromonomer (MB) used as a copolymer component of the graft copolymer resin will be described more specifically. The monofunctional macromonomer (MB) is formed by combining a polymerizable double bond group represented by the general formula (III) with at least one of the polymer components represented by the general formulas (IVa) and (IVb). Certain polar groups (-
COOH group, -PO ₃ H ₂ group, -SO ₃ H group, -OH group, A CHO group and / or an acid anhydride-containing group) and a weight-average molecular weight of 2 × 10 ⁴ , which is bound to only one end of a polymer main chain containing at least one of the polymer components.
These are:

In the general formulas (III), (IVa) and (IVb),
The hydrocarbon groups contained in c ₁ , c ₂ , X ₀ , d ₁ , d ₂ , X ₁ , Q ₁ and Q ₀ each have the indicated carbon number (as an unsubstituted hydrocarbon group), These hydrocarbon groups may have a substituent.

In the general formula (III), X ₀ represents —COO—, —OCO—,
_{-CH 2 OCO -, - CH 2} OO -, - O -, - SO 2 -, - CO -, -
CONHCOO−, −CONHCONH−, Or Represents Here, R ₃₁ is, in addition to a hydrogen atom, a preferable hydrocarbon group as an alkyl group having 1 to 18 carbon atoms which may be substituted (for example, a methyl group, an ethyl group, a propyl group,
Butyl, heptyl, hexyl, octyl, decyl, dodecyl, hexadecyl, octadecyl,
2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group, 2-methoxyethyl group, 3-bromopropyl group, etc.), having 4 to 4 carbon atoms.
18 alkenyl groups which may be substituted (for example, 2-methyl-1-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group, 1-pentenyl group, 1-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group and the like, and optionally substituted aralkyl group having 7 to 12 carbon atoms (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group,
A naphthylethyl group, a chlorobenzyl group, a bromobenzyl group, a methylbenzyl group, an ethylbenzyl group, a methoxybenzyl group, a ditylbenzyl group, a dimethoxybenzyl group, etc.), an optionally substituted alicyclic group having 5 to 8 carbon atoms (for example, A cyclohexyl group, a 2-cyclohexylethyl group,
2-cyclopentylethyl group or the like and an optionally substituted aromatic group having 6 to 12 carbon atoms (for example, phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl group, octylphenyl group, dodecyl) Phenyl, methoxyphenyl, ethoxyphenyl, butoxyphenyl, decyloxyphenyl, chlorophenyl, dichlorophenyl, bromophenyl, cyanophenyl, acetylphenyl, methoxycarbonylphenyl, ethoxycarbonylphenyl, butoxycarbonyl Phenyl group, acetamidophenyl group, propioamidophenyl group, dodecyloylamidophenyl group, etc.).

X ₀ In the case where is represented, the benzene ring may have a substituent. Examples of the substituent include a halogen atom (eg, chlorine atom, bromine atom, etc.), an alkyl group (eg, methyl group, ethyl group, propyl group, butyl group, chloromethyl group, methoxymethyl group, etc.), an alkoxy group (eg, methoxy group, Ethoxy groups,
A propoxy group, a butoxy group, etc.).

c ₁ and c ₂ may be the same or different from each other, and are preferably a hydrogen atom, a halogen atom (for example, a chlorine atom,
A bromine atom), a cyano group, an alkyl group having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, etc.), - COOZ COOZ ₄ (Z ₄ via the ₄ or hydrocarbons Preferably represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, an alkenyl group, an aralkyl group, an alicyclic group or an aryl group, which may be substituted, and specifically,
Represents the same content as described for R ₃₁ above)
Represents

Examples of the hydrocarbon in the —COO—Z ₄ group via the above hydrocarbon include a methylene group, an ethylene group, and a propylene group.

More preferably, for general formula (III), X ₀ is -COO
-, - OCO -, - CH 2 OCO -, - CH 2 COO -, - O -, - CON
HCOO -, - CONHCONH -, - CONH -, - SO 2 NH- or And c ₁ and c ₂ may be the same or different from each other,
Each a hydrogen atom, a methyl group, -COOZ ₆ or -CH ₂ COOZ ₆ ｛Z ₆
Represents more preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, etc.). Represents｝. Still more preferably, either one of c ₁ and c ₂ represents a hydrogen atom.

That is, as the polymerizable double bond group represented by the general formula (III), specifically, And the like.

In the general formula (IVa) or (IVb), X ₁ is a group represented by the formula (II)
Represents the same content as X _{0 in} I). d ₁ and d ₂ may be the same or different and represent the same contents as c ₁ and c _{2 in} formula (III).

Q ₁ represents an aliphatic group having 1 to 18 carbon atoms or an aromatic group having 6 to 12 carbon atoms.

Specifically, an alkyl group having 1 to 18 carbon atoms which may be substituted (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a heptyl group, a hexyl group, an octyl group, a decyl group,
Dodecyl, tridecyl, hexadecyl, octadecyl, 2-chloroethyl, 2-bromoethyl, 2
-Hydroxylethyl group, 2-methoxyethyl group, 2-
Ethoxyethyl group, 2-cyanoethyl group, 3-chloropropyl group, 2- (trimethoxysilyl) ethyl group, 2-
Tetrahydrofuryl group, 2-thienylethyl group, 2-N,
N-dimethylaminoethyl group, 2-N, N-diethylaminoethyl group, etc., C5-C8 cycloalkyl group (for example, cycloheptyl group, cyclohexyl group, cyclooctyl group, etc.), C7-C12 substitution Aralkyl groups (eg, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromobenzyl group, dichlorobenzyl group, methylbenzyl group, chloro-methyl An aliphatic group such as a benzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a methoxybenzyl group, and the like;
Optionally substituted aryl group (for example, phenyl group,
And aromatic groups such as a tolyl group, a xylyl group, a chlorophenyl group, a bromophenyl group, a dichlorophenyl group, a chloro-methyl-phenyl group, a methoxyphenyl group, a methoxycarbonylphenyl group, a naphthyl group and a chloronaphthyl group.

In the formula (IVa), X ₁ is preferably -COO-, -OCO
_{-, - CH 2 COO -,} - CH 2 OCO -, - O -, - CO -, - CONH
COO -, - CONHCONH -, - CONH -, - SO 2 NH- or Represents

Preferred examples of d ₁ and d ₂ represent the same contents as those of c ₁ and c ₂ described above.

In the general formula (IV b), Q ₀ is -CN, -CONH ₂ or Y represents a hydrogen atom, a halogen atom (eg, a chlorine atom, a bromine atom, etc.), an alkoxy group (eg, a methoxy group,
Ethoxy, propoxy, butoxy, etc.) or -CO
OZ ₅ (Z ₅ preferably represents an alkyl group, an aralkyl group or an aryl group having 7 to 12 carbon atoms having 1 to 8 carbon atoms).

The macromonomer (MB) may contain two or more polymer components represented by the formulas (IVa) and / or (IVb). When Q ₁ is an aliphatic group, the aliphatic group having 6 to 12 carbon atoms accounts for 20% of the total polymer component in the macromonomer (MB).
It is preferable to use it in a range not exceeding the weight%.

Further, when X ₁ in the general formula (IVa) is —COO—, in all the polymer components in the macromonomer (MB),
At least 30% by weight of the polymer component of the formula (IVa)
It is preferable to contain the above.

Further, in the macromonomer (MB), the formula (IVa)
And / or copolymerized as a third component together with the copolymer component represented by (IV b), polar group (-COOH group, -PO ₃ H
₂ groups, -SO ₃ H group, OH group, -CHO group, acid anhydride containing group) as a component containing
Any vinyl compound containing the above-mentioned polar group which can be copolymerized with the above-mentioned macromonomer (MB) can be used. For example, "Polymer Data Handbook [Basic Edition]" edited by The Society of Polymer Science, Baifukan ( 1986). Specifically, acrylic acid, α- and / or β-substituted acrylic acid (for example, α-acetoxy form, α-acetoxymethyl form, α (2-aminonoethyl form, α-chloro form,
α-bromo, α-fluoro, α-tributylsilyl, α-cyano, β-chloro, β-bromo, α-
Chloro form, β-mesoxy form, α, β-dichloro form, etc.),
Methacrylic acid, itaconic acid, itaconic acid half esters,
Itaconic acid semiamides, crotonic acid, 2-alkenyl carboxylic acids (eg, 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,
Vinylbenzenecarboxylic acid, vinylbenzenesulfonic acid, vinylsulfonic acid, vinylphosphonic acid, dicarboxylic acids, half-ester derivatives of vinyl or allyl groups of alcohols, and ester derivatives of these carboxylic acids or sulfonic acids, and substituents of amide derivatives Among them, compounds containing the polar group are exemplified.

In the above, R ₀ has the same contents as R, and the same applies to the acid anhydride-containing group. Examples of the OH group include, in addition to the phenolic OH group described in the resin [A], an alcohol having a vinyl group or an allyl group (for example, an ester substituent such as allyl alcohol, methacrylic acid ester and acrylamide, an N-substituent). Among them, compounds containing an -OH group and the like can be mentioned.

For example, the following monomers are shown as examples, but the scope of the present invention is not limited thereto.

Here, in each of the following examples, P ₁ is -H, -CH ₃ , -C
indicates l, -Br, -CN, a -CH ₂ COOCH ₃ or -CH ₂ COOH, P ₂
Represents -H or -CH _3, j represents an integer of 2 to 18, k
Represents an integer of 2 to 5, h represents an integer of 1 to 4, and i represents an integer of 1 to 12.

_{(B-15) CH 2 =} CHCH 2 OCO (CH 2) i COOH (B-16) CH 2 = CHCH 2 h COOH (B-49) CH ₂ = CHCH _{2 h} OH (B-52) CH ₂ = CHCH _{2 h} OCO (CH _{2 j} OH The amount of the polar group-containing copolymer component in the total polymer component in the macromonomer (MB) is preferably 0.5 to 50 parts by weight, more preferably 1 to 50 parts by weight, per 100 parts by weight of the total polymer component. ~ 40 parts by weight.

When the monofunctional macromonomer (MB) composed of the polar group-containing random copolymer is contained in the resin [B] as a copolymer component, it is contained in all the graft portions in the resin [B]. The total amount of the polar group-containing components is preferably 0.1 to 10 parts by weight per 100 parts by weight of all polymer components in the resin [B]. More preferably, a -COOH group,-
When it contains an acidic group selected from SO ₃ H groups and -PO ₃ H ₂ groups, the resin (B), the total amount present in the graft portion 0.
It is 1 to 5% by weight.

As the polymer component in the macromonomer (MB), other polymer components other than these may be contained. For example, acrylonitrile, methacrylonitrile, acrylamide as monomers corresponding to other polymerizable repeating units Kind,
Methacrylamides, styrene and derivatives thereof (for example, vinyl toluene, chlorostyrene, dichlorostyrene,
Bromostyrene, hydroxymethylstyrene, N, N-dimethylaminomethylstyrene, etc., and heterocyclic vinyls (eg, vinylpyridine, vinylimidazole, vinylpyrrolidone, vinylthiophene, vinylpyrazole, vinyldioxane, vinyloxazine, etc.). .

When these other monomers are contained, the amount is preferably 1 to 20 parts by weight per 100 parts by weight of the entire polymer component of the macromonomer (MB).

As described above, the macromonomer (MB) used in the present invention is a random monomer comprising at least a repeating unit represented by the general formula (IVa) and / or (IVb) and a repeating unit containing a specific polar group. The polymerizable double bond group represented by the general formula (III) is directly bonded to only one terminal of the polymer main chain, or has a chemical structure in which it is bonded by an arbitrary linking group. Examples of the linking group for linking the component of the formula (III) with the component of the formula (IVa) or (IVb) or the component containing a polar group include a carbon-carbon bond (single bond or double bond) and a carbon-heteroatom bond ( The hetero atom includes, for example, an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, etc.), and an arbitrary combination of atomic groups of a hetero atom-hetero atom bond.

More specific linking groups include [R ₃₂ and R ₃₃ represent a hydrogen atom, a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, etc.), a cyano group, a hydroxyl group, an alkyl group (eg, a methyl group, an ethyl group, a propyl group, etc.)] , CH = CH, -O-, -S-, -COO -, - SO ₂ -, -NHCOO-, -NHCONH-, [R ₃₄ and R _{35 each} represent a hydrogen atom, a hydrocarbon group having the same content as Q ₁ in the formula (IVa) or the like] or a single linking group selected from an atomic group or an arbitrary combination thereof. Represents two or more linking groups configured.

When the weight average molecular weight of the macromonomer (MB) exceeds 2 × 10 ⁴ , the copolymerizability with the monomer represented by the formula (V) decreases, which is not preferable. On the other hand, if the weight average molecular weight is too small, the effect of improving the electrophotographic properties of the photosensitive layer is reduced, so that the weight average molecular weight is preferably 1 × 10 ³ or more.

The macromonomer (MB) used in the present invention can be produced by a conventionally known synthesis method. In particular,
A terminal obtained by radical polymerization using a polymerization initiator and / or a chain transfer agent containing a reactive group such as a carboxyl group, a carboxy halide group, a hydroxyl group, an amino group, a halogen atom, and an epoxy group in a molecule. It is synthesized by a method such as a radical polymerization method in which an oligomer having a reactive group is reacted with various reagents to form a macromonomer.

Specifically, P. Dreyfuss & RPQuirk, Encycl.Poly
m.Sci.Eng., 7 , 551 (1987), PFRempp, E.Franta,
Adu, Polym. Sci. 58 , 1 (1984), Yusuke Kawakami, Chemical Industry, 38 , 56 (1987), Yuya Yamashita, Polymer, 31 , 988 (198
2), Shiro Kobayashi, Polymer, 30 , Koichi Ito, Polymer Processing, 3
5 , 262 (1986), Kishiro Higashi, Takashi Tsuda, Functional Materials, 1987 N
It can be synthesized according to the methods described in o.10, 5 and other reviews and references and patents cited therein.

However, since the macromonomer (MB) of the present invention contains an acidic group as the establishment of the repeating unit, it is synthesized in consideration of the following, for example, in the synthesis.

As one of the methods, for example, as shown in the following reaction formula (2), radical polymerization and terminal reactive groups are carried out by using a monomer containing a polar group-protected functional group in the form described above. Is introduced.

Polar group (-SO ₃ H groups contained randomly in the macromonomer to be subjected to the present invention (MB), -PO ₃ H ₂ group, -COO
H group, The protecting group reaction and the deprotection reaction (for example, hydrolysis reaction, hydrogenolysis reaction, oxidative decomposition reaction, etc.) of -OH group, -CHO group, acid anhydride-containing group) can be performed by a conventionally known method. . Specifically, JFWMcOmie, “Protec
tive Gvoups in Organic Chemistry ", Plenum Press (1
973), TWGreene, “Protective Gvoups in Organi
c Synthesis ", John Wiley & Sous (1981), Ryohei Oda" Polymer Fine Chemicals "Kodansha (1976), Yoshio Iwakura, Keisuke Kurita" Reactive Polymers "Kodansha (1977),
Berneretal, J. Radiation Curing, 1986, No. 10, P10,
JP-A-62-212669, JP-A-62-286064, JP-A-62-28664
No. 210475, JP-A-62-195684, JP-A-62-258476,
JP-A-63-260439, Japanese Patent Application No. 62-220510, Japanese Patent Application No. 62-220439
It can be synthesized using the method described in 226692 and the like.

As another method, for example, as shown in the following reaction formula (3), after synthesizing an oligomer as described above, a “specific reactive group” bonded to one end of the oligomer is used.
Is a method of synthesizing by reacting with a reagent containing a polymerized double bond group that reacts only with “specific reactivity” by utilizing the difference in reactivity between the polymer and the polar group contained in the oligomer. .

As shown in the reaction formula (3), specific examples of combinations of the specific functional groups are shown in Table A as follows. However, the present invention is not limited to these, and it is important that macromonomerization can be achieved without protecting the polar group in the oligomer by utilizing the selectivity of the reaction in a normal organic chemical reaction. That should be done.

Examples of the chain transfer agent that can be used include, for example, the polar group or a mercapto compound containing a substituent that can be later derived into the polar group (eg, thioglycolic acid, thiomalic acid, thiosalicylic acid, 2-mercaptopropionic acid,
3-mercaptopropionic acid, 3-mercaptobutyric acid, N
-(2-mercaptopropionyl) glycine, 2-mercaptonicotinic acid, 3- [N- (2-mercaptoethyl) carbamoyl] propionic acid, 3- [N- (2-mercaptoethyl) amino] propionic acid, N- ( 3-mercaptopropionyl) alanine, 2-mercaptoethanesulfonic acid, 3-mercaptopropanesulfonic acid, 4
-Mercaptobutanesulfonic acid, 2-mercaptoethanol, 3-mercapto-1,2-propanediol, 1-
Mercapto-2-propanol, 3-mercapto-2-
Butanol, mercaptophenol, 2-mercaptoethylamine, 2-mercapimidazole, 2-mercapto-3-pyridinol) or an oxidized form of these mercapto compounds, or the above-mentioned polar group- or substituent-containing iodinated alkyl compound (E.g., iodoacetic acid, iodopropionic acid, 2-iodoethanol, 2-iodoethanesulfonic acid, 3-iodopropanesulfonic acid, etc.). Preferably, a mercapto compound is used.

Specific reactive group-containing polymerization initiators that can be used include, for example, 2,2′-azobis (2-cyanopropanol), 2,2′-azobis (2-cyanopentanol), 4,4 ′ -Azobis (4-cyanovaleric acid), 4,4'-
Azobis (4-cyanovaleric acid chloride), 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane, 2,2'-azobis [2- (2-imidazoline-2- Yl) propane], 2,2'-azobis [2-
(3,4,5,6-tetrahydropyrimidin-2-yl) propane], 2,2'-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane}, 2 , 2'-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] and the like, and derivatives thereof.

These chain transfer agents or polymerization initiators are each 0.1 to 15% by weight based on 100 parts by weight of all monomers, and are preferably
0.5 to 10% by weight.

Specific examples of the macromonomer (MB) of the present invention include the following compounds. However, the scope of the present invention is not limited to these. In each of the following examples, P ₂ represents -H or CH ₃ , and P ₃ represents-
H, indicates -CH ₃ or -CH ₂ COOCH _3, R ₄₁ is -C _n H _{2n +} 1 _(n
Is an integer of _{1~18), - CH 2 C 6} H 5, (Y ₁ and Y ₂ each represent —H, —Cl, —Br, —CH ₃ , —COCH ₃ or —COOCH ₃ ), The illustrated, W ₁ is -CN, -OCOCH _3, shows a -CONH ₂ or -C ₆ H _5, W ₂ represents -Cl, -Br, -CN, or -OCH _3, alpha is 2
Represents an integer of 18, β represents an integer of 2 to 12, and γ represents 2 to 4
Indicates an integer.

On the other hand, the monomer copolymerized with the macromonomer (MB) is represented by the general formula (V). In equation (V),
e ₁ and e ₂ may be the same or different from each other, and c of the formula (III)
₁ represents a c ₂ same content as. X ₂ is X in the formula (IVa)
₁ and, Q ₂ represents the same content each and to Q ₁ in the formula (IV a).

In the resin of the present invention, the composition ratio of the copolymer component having a macromonomer (MB) as a repeating unit and the copolymer component having a monomer represented by the general formula (V) as a repeating unit is preferably from 1 to 70. / 30-99 (weight composition ratio), more preferably 5-60 / 95-40 weight ratio.

The polymerization Lord in the chain, -PO ₃ H ₂ group, -SO ₃ H group, -COOH
Those which do not contain a copolymer component containing a polar group such as a group, a —OH group, and a —PO ₃ R ₀ H group are preferred. In addition, the resin [B] of the present invention may contain, in addition to the macromonomer (MB) and the monomer of the general formula (V), monomers other than these as a further copolymerization component.

For example, α-olefins, vinyl alkanoate or allyl esters, acrylonitrile, methacrylonitrile, vinyl ethers, acrylamides, methacrylamides, styrenes, heterocyclic vinyls (for example, vinylpyrrolidone, vinylpyridine, vinylimidazole,
Vinyl thiophene, vinyl imidazoline, vinyl pyrazole, vinyl dioxane, vinyl quinoline, vinyl thiazole, vinyl oxazine, etc.).

However, these other monomers other than the macromonomer (MB) and the monomer of the formula (V) do not exceed 20% by weight in the copolymer.

Further, the resin [B] has only one end of the polymer main chain containing at least one kind of the repeating unit represented by the general formula (V) and at least one kind of the repeating unit represented by the macromonomer. A copolymer (resin [B ']) formed by bonding at least one of them may be used. Further, the copolymers [B] and [B '] may be used in combination. Here, the polar group has a chemical structure in which the polar group is directly bonded to one end of the polymer main chain or is bonded via an arbitrary linking group.

Examples of the bonding group include a carbon-carbon bond (single bond or double bond), a carbon-heteroatom bond (for example, an oxygen atom, a sulfur atom, a nitrogen atom, and a silicon atom), and a heteroatom-heteroatom bond. It is composed of any combination of atomic groups. For example, CH = CH, -O-, -S-, -COO -, - SO ₂ -, -NHCOO-, -NHCONH-, (R ₃₂ to R ₃₅ are each the R ₃₂ to R ₃₅ the same showing the contents and) an atomic group selected from such alone, or two or more linking groups composed of combinations.

In the resin [B] used in the present invention, in order to synthesize the resin [B ′] in which the polar group is bonded to the terminal of the polymer main chain, at least the above-mentioned macromonomer (MB) and the general formula ( This can be achieved by using a polymerization initiator or a chain transfer agent containing, in the molecule, the polar group or a specific reactive group derivable therefrom during the polymerization reaction with the monomer represented by V).

Specifically, it can be obtained in the same manner as in the method of the oligomer having a single-terminal reactive group as described above in the synthesis of a macromonomer.

In the electrophotographic photoreceptor of the present invention, higher mechanical strength may be desired while maintaining its excellent electrophotographic properties. For this purpose, a method of introducing a heat and / or photocurable functional group into the main chain of the graft copolymer can be applied.

That is, in the present invention, the resin [A] and / or the resin [B]
In the above, a monomer containing at least one heat and / or photocurable functional group may be further contained as a copolymerization component. The heat and / or photocurable functional group appropriately crosslinks the polymers, thereby strengthening the interaction between the polymers and improving the strength as a film. Therefore, the resin of the present invention further containing such a heat and / or photo-curable functional group can prevent the interaction between the binder resin and the appropriate adsorption / coating of the surface of the zinc oxide particles and the binder resin. It has the effect of strengthening the film and, as a result, improving the film strength.

The heat and / or light curable functional group of the present invention refers to a functional group capable of curing a resin by at least one of heat and light.

The “thermosetting functional group (functional group that performs a thermosetting reaction)” in the present invention includes, for example, Tsuyoshi Endo “Refinement of thermosetting polymer”
(CMC Co., Ltd., 1986), Yuji Harasaki, "The latest binder technology handbook" Chapter II-I (General Technology Center, 1985), Takayuki Otsu, "Synthesis, design and new application development of acrylic resin" (Chubu Management Development) Center Publishing Department, 1985), Eizo Omori "Functional Acrylic Resin" (Techno System, 1985)
The functional groups described in the references can be used in reviews such as annual publications.

For example -OH group, -SH group, -NH ₂ group, -NHR ₂₁ group (R ₂₁ represents a hydrocarbon group, the B ₁ same content as the previous in X of specifically formula (III) Express.) -CONHCH ₂ OR ₂₂ (R ₂₂ is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms (for example, a methyl group, an ethyl group, a propyl group,
Butyl group, hexyl group, octyl group, etc.) -N = C = O group or {Γ ₁ and γ ₂ each represent a hydrogen atom, a halogen atom (eg, a chlorine atom, a bromine atom, etc.) or an alkyl group having 1 to 4 carbon atoms (eg, a methyl group, an ethyl group, etc.)}, and the like. . As the polymerizable double bond, specifically, CH ₂ CHCH—, _{CH 2 = CH-NHCO-, CH} 2 = CH-CH 2 - NHCO-, CH 2 = CH-SO 2 -, CH 2 = CH-CO-, CH 2 = CH-O-, CH 2 = CH-S -, And the like.

Examples of the “photo-curable functional group” of the present invention include, for example, Takahiro Tsunoda, “Photosensitive Resin”, Printing Society Publishing Division (1972), Mototaro Nagamatsu, Hideo Inui, “Photosensitive Polymer” Kodansha (1977) G .
A. Delgerne, “Encyclopedia of Polymer Science and T
Functional groups described in, for example, echnology, Supplement. "Vol I (1976). Specifically, addition polymerization groups such as allyl ester groups and vinyl ester groups, cinnamoyl groups, and optionally substituted maleimides And a duplex group such as a ring group.

In the present invention, in order to synthesize a resin containing a heat and / or photocurable functional group, the heat and / or photocurable functional group is used as a copolymer component containing the heat and / or photocurable functional group. A monomer containing a group may be used.

When the resin of the present invention contains the thermosetting functional group, a reaction accelerator may be added as necessary in order to promote a crosslinking reaction in the photosensitive layer film. In the case of a reaction mode for forming a chemical bond between functional groups, for example, an organic acid (acetic acid, propionic acid, butyric acid, benzenesulfonic acid, p-toluenesulfonic acid and the like), a cross-linking agent and the like can be mentioned.

Specific examples of the cross-linking agent include compounds described in Shinzo Yamashita and Tosuke Kaneko, “Cross-Linking Agent Handbook”, Taiseisha (1981) and the like. For example, commonly used crosslinking agents such as organic silane, polyurethane, and polyisocyanate, and curing agents such as epoxy resin and melamine resin can be used.

In the case of the polymerization reaction mode, a polymerization initiator (peroxide,
Azobis-based compounds and the like, preferably azobis-based polymerization initiators), and monomers having a polyfunctional polymerizable group (for example, vinyl methacrylate, acrylic methacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, divinyl succinate) Acid esters, divinyl adipates, diallylsuccinates, 2-methylvinyl methacrylate, divinylbenzene, etc.).

In the present invention, when a binder resin containing such a thermosetting functional group is used, a thermosetting treatment is performed.
This thermosetting treatment can be performed by strictly setting the drying conditions at the time of the conventional photoreceptor production. For example, 60 ℃ ~ 12
The treatment may be performed at 0 ° C. for 5 minutes to 120 minutes. When the above-described reaction accelerator is used in combination, the treatment can be performed under milder conditions.

The ratio of the amount of the resin [A] and the amount of the resin [B] used in the present invention depends on the type, particle size, and surface state of the inorganic photoconductive material used, but generally the ratio of the resin [A] and the resin [B] used. Is 5 to 80 to 95 to 20 (weight ratio), preferably
It is 10-60 to 90-40 (weight ratio).

In the present invention, the resin [A] and the resin [B] according to the present invention
(Including [B ']), other resins may be used in combination. Examples of such resins include alkyd resins, polybutyral resins, polyolefins, ethylene-vinyl acetate copolymers, styrene resins, styrene-butadiene resins, acrylate butadiene resins, and vinyl alkanoate resins.

When the other resin exceeds 30% (weight ratio) of the total amount of the binder resin using the resin of the present invention, the effect of the present invention (especially, improvement of electrostatic characteristics) is lost.

Examples of the inorganic photoconductive material used in the present invention include zinc oxide, titanium oxide, zinc sulfide, cadmium sulfide, cadmium carbonate, zinc selenide, cadmium selenide, tellurium selenide, and lead sulfide.

The total amount of the 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 as spectral sensitizers as needed. For example, Harumiya Miyamoto, Hidehiko Takei, Imaging 1973 (No.8), page 12, CJ Young et al., RC
A Review 15, 469 (1954), Wataru equality Kiyota, Telecommunications Society of J 63-C (No.2), 97 (1980), Yuji like Yuji, Industrial Chemistry Journal 66 78 and 188 (1963), Tadaaki Tani , Journal of Japan photographic Society 35, 208 (1972) carbonium-based dyes review references such as, diphenylmethane dyes, triphenylmethane dyes,
Xanthene dyes, phthalein dyes, polymethine dyes (for example, oxonol dyes, merocyanine dyes, cyanine dyes, rhodacyanine dyes, styryl dyes, and the like), phthalocyanine dyes (which may contain metals), and the like.

More specifically, those using mainly carbonium dyes, triphenylmethane dyes, xanthene dyes, and phthalein dyes are described in JP-B-51-452,
-90334, JP-A-50-114227, JP-A-53-39130,
JP-A-53-82353, U.S. Pat. No. 3,052,540, U.S. Pat. No. 4,054,450, and JP-A-57-16456 are examples.

Oxonol dyes, merocyanine dyes, cyanine dyes, polymethine dyes such as rhodacyanine dyes, F.
M. Hamar `` The Cyanine Dyes and Related Compounds ''
Can be used, more specifically, more specifically,
U.S. Patent 3,047,384, U.S. Patent 3,110,591, U.S. Patent 3,121,008, U.S. Patent 3,125,447, U.S. Patent 3,128,179, U.S. Patent 3,132,942, U.S. Pat.
622,317, UK Patent 1,226,892, UK Patent 1,309,
No. 274, British Patent No. 1,405,898, JP-B-48-7814, JP-B-55-18892 and the like.

Further, as a polymethine dye for spectrally sensitizing the near infrared to infrared light region having a long wavelength of 700 nm or more, JP-A-47-840, JP-A-47-44180, JP-B-51-41061, 1949-5034
No., JP-A-49-45122, JP-A-57-46245, JP-A-56
No. -35141, JP-A-57-157254, JP-A-61-26044,
JP-A-61-27551, U.S. Pat.No. 3,619,154, U.S. Pat.No.4,175,956, `` Research Disclosure '' 1982, 21
6, pages 117 to 118 and the like. The photoreceptor of the present invention is excellent in that even when various sensitizing dyes are used in combination, the performance is hardly changed by the sensitizing dye. Furthermore, various conventionally known additives for an electrophotographic photosensitive layer such as a chemical sensitizer can be used in combination, if necessary.
For example, the review mentioned above: Imaging 1973 (No. 8) No. 12
"Recent development and commercialization of photoconductive materials and photoreceptors", e.g., electron accepting compounds (e.g., halogen, benzoquinone, chloranil, acid anhydride, organic carboxylic acid, etc.) and Hiroshi Komon, which are described in pages and other reviews. Chapters 4 to 6 include polyarylalkane compounds, hindered phenol compounds, p-phenylenediamine compounds, and the like, which are reviewed in Japanese Science Information Co., Ltd., Publishing Division (1986).

The amounts of these various additives are not particularly limited, but are usually 0.0001 to 2.0 parts by weight based on 100 parts by weight of the photoconductor.

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

When a photoconductive layer is used as the charge generation layer of the photoreceptor having the charge generation layer and the charge transport layer, the thickness of the charge generation layer is preferably 0.01 to 1 μm, particularly preferably 0.05 to 0.5 μm.

In some cases, an insulating layer is provided for the main purpose of protecting the photoreceptor, improving durability, and improving dark attenuation characteristics. At this time, the insulating layer is set relatively thin, and the insulating layer provided when the photosensitive member is used in a specific electrophotographic process is set relatively thick.

In the latter case, the thickness of the insulating layer is between 5 and 70 μm, especially 10
Set to ~ 50μ.

Examples of the charge transport material of the laminated photoreceptor include polyvinyl carbazole, oxazole dyes, pyrazoline dyes, and triphenylmethane dyes. The thickness of the charge transport layer is preferably 5 to 40 μm, particularly preferably 10 to 30 μm.

Typical examples of the resin used for forming the insulating layer or the charge transport layer include polystyrene resin, polyester resin, cellulose resin, polyether resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, A thermoplastic resin of a polyacryl resin, a polyolefin resin, a urethane resin, an epoxy resin, a melamine resin, a silicone resin, and a curable resin are appropriately used.

The photoconductive layer according to the present invention can be provided on a conventionally known support. Generally, the support of the electrophotographic photosensitive layer is preferably electrically conductive, and the conductive support may be completely impregnated with a low-resistance substance such as a metal, paper, or plastic sheet in the same manner as in the related art. A substrate that has been subjected to a conductive treatment, for example, by applying a conductivity to the back surface of the substrate (the surface opposite to the surface on which the photosensitive layer is provided), and further coated with at least one layer for the purpose of preventing curling and the like. A substrate provided with a water-resistant adhesive layer on its surface, a substrate provided with at least one or more precoat layers as necessary on the surface layer of the support, or a substrate conductive plastic on which Al or the like is deposited is laminated on paper. Can be used.

Specifically, as an example of a conductive substrate or a conductive material, Yukio Sakamoto, Electrophotography, 14, (No. 1), p2-11 (197)
5), Hiroyuki Moriga, “Chemistry of Introductory Special Paper”, Polymer Publishing Association (1
975), MF Hoover, J. Macromol. Sci. Chem. A-4 (6),
Those described in pages 1327 to 1417 (1970) and the like are used.

(Example) An example of the present invention will be described below, but the content of the present invention is not limited thereto.

[Synthesis of Resin [A]] Synthesis Example 1 of Resin [A] 1: [A-1] 95 g of ethyl methacrylate and 200 of tetrahydrofuran
g of the mixed solution was sufficiently degassed under a nitrogen stream and cooled to -20 ° C. 1.5 g of 1,1-diphenylbutyllithium was added and 12
Reacted for hours. Further, to this mixed solution, a mixed solution of 5 g of triphenylmethyl methacrylate and 5 g of tetrahydrofuran was sufficiently degassed under a nitrogen stream, and then added, and the mixture was further reacted for 8 hours. The mixture was brought to 0 ° C.,
ml was added and reacted for 30 minutes to terminate the polymerization. The temperature of the resulting polymer solution was adjusted to 30 ° C. with stirring, to which 3 ml of a 30% ethanol solution of hydrogen chloride was added, followed by stirring for 1 hour. Next, the solvent was distilled off under reduced pressure until the total amount of the reaction mixture became half, and the reaction mixture was reprecipitated in petroleum ether 1.

The polymer obtained by collecting the precipitate and drying under reduced pressure is:
The yield was 70 g with a weight of 8.5 x 10 ³ .

Synthesis Example 2 of Resin [A]: [A-2] A mixed solution of 46 g of n-butyl methacrylate, 0.5 g of (tetraphenylporphinato) aluminum methyl and 60 g of methylene chloride was heated to 30 ° C. under a nitrogen stream. This was irradiated with light from a 300 W-xenon lamp through a glass filter from a distance of 25 cm, and reacted for 12 hours. To this mixture was further added 4 g of benzyl methacrylate.
After light irradiation for 3 hours, 3 g of methanol was added to the reaction mixture, followed by stirring for 30 minutes to terminate the reaction. Next, Pd-C was added to the reaction mixture, and a catalytic reduction reaction was performed at a temperature of 25 ° C. for 1 hour.

After filtering off the insoluble matter, the precipitate was reprecipitated in 500 ml of petroleum ether,
The precipitate was collected and dried. The obtained polymer was obtained in a yield of 33 g.
It was w9.3 × 10 ³ .

Synthesis Example 3: Resin [A]: [A-3] 2-chloro-6-methylphenyl methacrylate 90 g
A mixed solution of 200 g of toluene and 200 g was sufficiently degassed under a nitrogen stream and cooled to 0 ° C. Then, 2.5 g of 1,1-diphenyl-3-methylpentyllithium was added, and the mixture was stirred for 6 hours. Further, 10 g of 4-vinylphenyloxytrimethylsilane was added to this mixture, and the mixture was stirred for 6 hours.
Stirred for 0 minutes.

The reaction mixture is then added to a 10% 30% hydrogen chloride ethanol solution.
g, and the mixture was stirred at 25 ° C. for 1 hour. The precipitate was reprecipitated in petroleum ether 1 and the collected precipitate was extracted with 300 ml of diethyl ether.
Washed and dried twice. The obtained polymer was w7 with a yield of 58 g.
It was 8 × 10 ³ .

Synthesis Example 4: Resin [A]: [A-4] A mixture of 95 g of phenyl methacrylate and 4.8 g of benzyl N, N-diethyldithiocarbamate was sealed in a vessel under a nitrogen stream, and heated to a temperature of 60 ° C. This was irradiated with light for 10 hours through a glass filter from a distance of 10 cm with a 400 W high-pressure mercury lamp, and photopolymerized.

To this were added 5 g of acrylic acid and 180 g of methyl ethyl ketone, followed by purging with nitrogen and light irradiation again for 10 hours.

The obtained reaction product was reprecipitated in hexane 1.5, collected and dried. The obtained polymer had a weight of 9.5 × 10 ³ in 68 g.

Synthesis Example 1 of Macromonomer (MB) 1: M-1 90 g of ethyl methacrylate, 10 g of 2-hydroxyethyl methacrylate, 5 g of thioglycolic acid and 200 of toluene
g of the mixed solution was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. 2,2'-azobisisobutyronitrile (abbreviation)
(AIBN) 1.0 g and reacted for 8 hours. Next, 8 g of glycidyl methacrylate, 1.0 g of N, N-dimethyldodecylamine and 0.5 g of t-butylhydroquinone were added to the reaction solution, and the mixture was stirred at a temperature of 100 ° C. for 12 hours. After cooling, the reaction solution was reprecipitated in n-hexane 2 to obtain 82 g of a white powder. The weight average molecular weight of the polymer was 3.8 × 10 ³ .

Synthesis Example 2 of Macromonomer (MB): 90 g of M-2 butyl methacrylate, 10 g of methacrylic acid, 2-
A mixed solution of 4 g of mercaptoethanol and 200 g of tetrahydrofuran was heated to a temperature of 70 ° C. under a nitrogen stream. AIBN1.2g
Was added and reacted for 8 hours.

Next, the reaction solution was cooled to 20 ° C. in a water bath,
Triethylamine (10.2 g) was added, and methacrylic acid chloride (14.5 g) was added dropwise with stirring at a temperature of 25 ° C. or lower. After the addition, the mixture was further stirred for 1 hour. Thereafter, 0.5 g of t-butylhydroquinone was added, the mixture was heated to a temperature of 60 ° C., and stirred for 4 hours.
After cooling, it is dropped into water 1 with stirring (about 10 minutes)
After stirring for 1 hour as it was and standing, water was removed by decantation. After washing twice with water, the residue was dissolved in 100 ml of tetrahydrofuran and reprecipitated in petroleum ether 2. The precipitate was collected by decantation and dried under reduced pressure. The yield of the obtained viscous material was 65 g, and the weight average molecular weight was 5.6 × 10 ³ .

Synthesis Example 3 of Macromonomer (MB): M-3 A mixed solution of 95 g of benzyl methacrylate, 5 g of 2-phosphonoethyl methacrylate, 4 g of 2-aminoethyl mercaptan and 200 g of tetrahydrofuran was added to a temperature of 70 ° C. while stirring under a nitrogen stream. Warmed.

Add 1.5g of AIBN and let it react for 4 hours.
5 g was added and reacted for 4 hours. Next, the reaction solution was cooled to a temperature of 20 ° C., and 10 g of acrylic acid anhydride was added thereto.
Stirred at 2525 ° C. for 1 hour. Next, 1.0 g of t-butylhydroquinone was added, and the mixture was stirred at a temperature of 50 to 60 ° C for 4 hours. After cooling,
While stirring in water 1, the reaction mixture was added dropwise over about 10 minutes, stirred for 1 hour and allowed to stand, and water was removed by decantation. After repeating the washing with water twice more, it was dissolved in 100 ml of tetrahydrofuran and reprecipitated in petroleum ether 2. The precipitate was collected by decantation and dried under reduced pressure. The yield of the obtained viscous material is 70 g.
And the weight average molecular weight was 7.4 × 10 ³ .

Synthesis Example 4 of Macromonomer (MB): M-4 95 g of 2-chlorophenyl methacrylate, 5 g of monomer having the following structure (I), 4 g of thioglycolic acid and 20 parts of toluene
0 g of the mixed solution was heated to a temperature of 70 ° C. under a nitrogen stream. AI
1.5 g of BN was added and reacted for 5 hours, and 0.5 g of AIBN was further added and reacted for 4 hours. Next, glycidyl methacrylate 12.4
g, 1.0 g of N, N-dimethyldodecylamine and 1.5 g of t-butylhydroquinone were added and reacted at 110 ° C. for 8 hours.
After cooling, the reaction mixture was mixed with 3 g of p-toluenesulfonic acid, 90 g
The solution was added to 100 ml of a vol% aqueous tetrahydrofuran solution and stirred at a temperature of 30 to 35 ° C for 1 hour. Water / ethanol [(1 /
3) The mixture was reprecipitated in a mixed solution 2 (volume ratio), and the precipitate was collected by decantation. This precipitate was dissolved in 200 ml of tetrahydrofuran and n-hexane 2 was added.
It was re-precipitated in the inside to obtain 58 g of powder. Weight average molecular weight is 7.6 × 10
^{Was 3} .

Synthesis example 5 of macromonomer (MB): M-5 95 g of 2,6-dichlorophenyl methacrylate, 3-g
A mixed solution of 5 g of (2′-nitrobenzyloxysulfonyl) propyl methacrylate, 150 g of toluene and 50 g of isopropyl alcohol was heated to a temperature of 80 ° C. under a nitrogen stream. 2,2'-azobis (2-cyanovaleric acid) (abbreviation: AC
V.) 5.0 g was added and reacted for 5 hours, and ACV 1.0 g was further added and reacted for 4 hours. After cooling, the reaction product was reprecipitated in methanol 2, and the powder was collected by filtration and dried under reduced pressure.

50 g of the above powder, 14 g of glycidyl methacrylate, 0.6 g of N, N-dimethyldosylamine, t-butyl hydroquinone 1.
A mixture of 0 g and 100 g of toluene was stirred at a temperature of 110 ° C. for 10 hours. After cooling to room temperature, the mixture was irradiated with light for 1 hour with stirring using a high-pressure mercury lamp of 80 W. Thereafter, the reaction mixture was reprecipitated in methanol 1, and the powder was collected by filtration and dried under reduced pressure. The yield was 34 g and the weight average molecular weight was 7.3 × 10 ³ .

Synthesis Example 1: Resin [B] of the present invention 1: [B-1] Benzyl methacrylate 80 g, macromonomer (MB)
A mixed solution of 20 g of the compound (M-2) of Synthesis Example 2 and 100 g of toluene was heated to a temperature of 75 ° C. under a nitrogen stream. 1,1 ′
-Azobis (cyclohexane-1-carbonianide)
(Abbreviation: ABCC) 0.8g and react for 4 hours, then AIB
N. 0.5 g was added and reacted for 3 hours.

W of the obtained copolymer was 1.0 × 10 ⁵ .

Synthesis Example 2: Resin [B] of the present invention: [B-2] 70 g of 2-chlorophenyl methacrylate, 30 g of compound (M-1) of Synthesis Example 1 of macromonomer (MB), 0.7 g of thioglycolic acid and 150 g of toluene The mixed solution was heated to a temperature of 80 ° C. under a nitrogen stream. After adding 0.5 g of ABCC and reacting for 5 hours, 0.3 g of ABCC was added and added for 3 hours.
2 g was added and reacted for 3 hours.

W of the obtained copolymer was 9.2 × 10 ⁴ .

Synthesis Example 3 of Resin [B] of the Present Invention: [B-3] 60 g of ethyl methacrylate, compound of Synthesis Example 4 of macromonomer (MB): A mixed solution of 25 g of (M-4), 15 g of methyl acrylate and 150 g of toluene. 75 ° C under nitrogen flow
Was heated. Add 0.5g of ACV and react for 5 hours.
0.3 g was added and reacted for 4 hours. W of the obtained copolymer is
It was 1.1 × 10 ⁵ .

Synthesis Examples 4 to 11 of Resin [B] of the Present Invention: [B-4] to [B
-11] Resin [B] was synthesized in the same manner as in Synthesis Example 1 of resin [B], using methacrylates and macromonomers corresponding to Table 1 below.

Synthesis Examples 12 to 19 of Resin [B] of the Present Invention: [B-12] to [B
-19] Resin [B] shown in Table 2 below was synthesized in the same manner as in Synthesis Example 2 of resin [B], except that the methacrylate and the macromonomer mercapto compound were each replaced.

The w of each resin was 9 × 10 ^{4 to} 1.1 × 10 ⁵ .

Synthesis Examples 20 to 27 of Resin [B] of the Present Invention: [B-20] to [B
-27] Resin [B] in Table 3 below was synthesized in the same manner as in Synthesis Example 3 of resin [B], except that the methacrylate, the macromonomer, and the azobis compound were each replaced.

The w of each resin [B] was 9.5 × 10 ^{4 to} 1.5 × 10 ⁵ .

Example 1 and Comparative Examples A to C Resin [A-3] 6 g (as solid content), resin [B-
1] A mixture of 0.018 g of cyanine dye [I] having the following structure and 300 g of toluene was dispersed in a ball mill for 4 hours to prepare a photosensitive layer-forming product. Apply with a wire bar so that the dry adhesion amount becomes 25 g / m ² , dry at 110 ° C for 30 seconds, and then
An electrophotographic light-sensitive material was prepared by being left at 0 ° C. and 65% RH for 24 hours.

Comparative Example A: Instead of the binder resin used in Example 1, 6 g of resin [R-1] having the following structure and 34 g of poly (ethyl methacrylate) (w2.4 × 10 ⁵ ): resin [R-2] were used. An electrophotographic photosensitive material was prepared in the same manner as in Example 1 except for using it.

Comparative Example B: The procedure of Example 1 was repeated, except that 6 g of the resin [R-3] and 34 g of the resin [R-2] having the following structure were used instead of the binder resin used in Example 1. A photographic light-sensitive material was prepared.

Comparative Example C: The procedure of Example 1 was repeated, except that 6 g of resin [R-3] and 34 g of resin [R-4] having the following structure were used instead of the binder resin used in Example 1. A photographic light-sensitive material was prepared.

The film properties (surface smoothness), electrostatic properties, imaging properties, and imaging properties of these photosensitive materials when the environmental conditions were 30 ° C. and 80% RH were examined. Further, when these photosensitive materials are used as an offset master, the photoconductive desensitizing property (expressed by the contact angle of the photoconductive layer with water after the desensitizing treatment) and printability (ground stain, Printing durability).

 The above results are summarized in Table-4.

The embodiments of the evaluation items shown in Table 4 are as follows.

Note 1) Smoothness of photoconductive layer: The obtained photosensitive material was measured for its smoothness (sec / cc) using a Beck smoothness tester (manufactured by Kumagaya Riko Co., Ltd.) under the condition of an air capacity of 1 cc. It was measured.

Note 2) Mechanical strength of photoconductive layer: The surface of the obtained photosensitive material was emery paper (#) with a load of 60 g / cm ² using a Haydon-14 type surface test material (manufactured by Shinto Chemical Co., Ltd.). The abrasion powder was removed 1000 times repeatedly to remove the abrasion powder, and the remaining film rate (%) was determined from the weight loss of the photosensitive layer, and the resulting value was defined as the mechanical strength.

Note 3) Electrostatic properties: Paper analyzer (Kawaguchi Electric Co., Ltd. paper analyzer) in a dark room at a temperature of 20 ° C and 65% RH.
After 20 seconds corona discharge -6kV with SP-428 type), allowed to stand for 10 seconds to measure the surface potential V ₁₀ at this time.
Next, the potential V ₁₃₀ after being allowed to stand in the dark for 120 seconds.
Is measured, and the retention of the potential after dark decay for 120 seconds, that is, the dark decay retention [DRR (%)] is (V ₁₃₀ / V ₁₀ ) × 100.
(%).

After charging the photoconductive surface to −500 V by corona discharge, the surface is irradiated with monochromatic light having a wavelength of 785 nm, and the surface potential (V ₁₀ ) becomes 1 /
The time required to decay to 10 is obtained, and the exposure amount E _1/10
(Erg / cm ² ) is calculated. Furthermore, after charging to -500 V by corona discharge in the same manner as in E _1/10 measurement, irradiation with monochromatic light having a wavelength of 785 nm was performed, and the time until the surface potential (V ₁₀ ) attenuated to 1/10 was determined. The quantity E _1/100 (erg / cm ² ) is calculated.

Note 4) Image-capturability: Each photosensitive material was allowed to stand for one day under the following environmental conditions. Next, it is charged with -5kV, and as a light source, gallium-aluminum-arsenic with 2.8mW output, semiconductor laser (oscillation wavelength 785nm)
Using ELP-T (manufactured by Fuji Photo Film Co., Ltd.) as a liquid developer after exposure at a pitch of 25 μm and a scanning speed of 300 m / sec under an irradiation dose of 50 erg / cm ² on the surface of the photosensitive material. The copied image (fog, image quality) obtained by developing and fixing was visually evaluated.

Environmental conditions at the time of imaging were 20 ° C 65% RH and 30 ° C 80% RH.

Note 5) Contact angle with water: Each photosensitive material is passed through an etching processor once using a solution obtained by diluting a desensitizing solution EPL-EX (manufactured by Fuji Photo Film Co., Ltd.) twice with distilled water. After desensitizing the surface of the photoconductive layer, a drop of distilled water 2III- is placed on the surface and the contact angle with the formed water is measured with a goniometer.

Note 6) Printing durability: Each photosensitive material is plate-made under the same conditions as in Note 4) to form a toner image, and desensitized under the same conditions as in Note 5) above, and used as an offset master. This indicates the number of sheets that can be printed on an offset printing machine (Sakurai Seisakusho Co., Ltd. Oliver 52) without causing background contamination of the non-image material of the printed matter and no problem in the image quality of the image portion. Is good).

As shown in Table 4, the photosensitive material of the present invention had good strength and electrostatic properties of the smooth film of the photoconductive layer, and the actual copied image was clear without background fog and the copied image was clear. This is presumed to be due to the photoconductor and the binder resin being sufficiently adsorbed and covering the particle surface. For the same reason, even when used as an offset master master, the desensitizing treatment with the desensitizing solution proceeds sufficiently, the contact angle with water of the non-image area is as small as 10 degrees or less, and the hydrophilicity is sufficiently increased. You can see that Even when the printed matter was actually examined and the background stain was observed, no background stain was observed.

Comparative Examples A to C are compared with the photosensitive material of the present invention.
The electrostatic characteristics have deteriorated. In Comparative Example C, the film strength was improved, and the electrostatic properties were also V ₁₀ , DRR, and E _1/10 .
Very good values were obtained. However, the E _1/10 value was twice as large as that of the light-sensitive material of the present invention. The E _1/100 value indicates how much potential remains in the non-image area (exposed area) after exposure in the actual imaging performance. This indicates that background contamination of the image portion will not occur.

Specifically, it is necessary to set the residual potential to -10 V or less, that is, scanning with a semiconductor laser beam depends on how much exposure is required in order to actually make V _R -10 V or less. With the exposure method, a small exposure
To the V _R below -10V, the (cost of the device, the accuracy of an optical system an optical path) optical system design of the copying machine is very important.

From the above, when an image was actually taken with an apparatus having a slightly reduced exposure dose, Comparative Example A had a remarkably low DRR, so that a satisfactory copied image could not be obtained. In Comparative Example B, the image deteriorated remarkably under the conditions of high temperature and high humidity, and the density of the image portion was reduced, thin lines and characters were blurred, and the ground fog was generated in the non-image portion. In Comparative Example C, the image was almost satisfactory under the condition of normal temperature and normal humidity, but under the condition of high temperature and high humidity, the occurrence of ground fogging and the thinning of the thin line in the image portion occurred. Further, even when used as an offset master, under the printing conditions that the photosensitive material of the present invention can print 10,000 sheets or more, in each of Comparative Examples A to C, non-image area stains are generated from printed printouts. have done. This was because a clear copied image was not obtained, and ground fog could not be removed by the desensitizing treatment.

As described above, an electrophotographic photosensitive member that satisfies electrostatic characteristics and printability only when the resin of the present invention is used is obtained.

Examples 2 to 17 In Example 1, the resin [A-3] and the resin [B-1
Each electrophotographic photoreceptor was produced in the same manner as in Example 1 except that each resin [A] and each resin [B] in Table 5 below were used instead of [1].

The electrostatic characteristics were measured in the same manner as in Example 1. The results are shown in Table 5 (however, described only under conditions of 30 ° C. and 80% RH).

Example 1 was used as an offset master master.
When printing was performed in the same manner as described above, all of them could print 10,000 sheets or more.

From the above, each photosensitive material of the present invention, the smoothness of the photoconductive layer,
The film strength, electrostatic properties, and printability were all favorable.

Furthermore, it was found that the use of the resin [A '] further improved electrostatic characteristics.

Examples 18 to 33 In Example 1, as a binder resin, 7.6 g of resin [A] and 34 g of resin [B] shown in Table 6 below were used, and instead of 0.02 g of cyanine dye [I], a dye having the following structure [ II) 0.019 g
An electrophotographic photosensitive material was produced under the same conditions as in Example 1 except that the above was changed to.

The photosensitive materials of the present invention are all excellent in chargeability, dark charge retention, and photosensitivity.
(80 ° C., 80% RH), a clear image without fog was obtained.

Furthermore, when this was used as an offset master master, 10,000 or more printed materials with clear image quality without background fog could be printed.

Examples 34 and 35 and Comparative Example D Either 6.5 g of resin [A-1] (Example 34) or resin [A-10] (Example 35), 33.5 g of resin [B-16], and 200 g of zinc oxide , 0.02 g of uranine, 0.04 g of rose bengal, 0.03 g of bromophenol blue, 0.20 g of phthalic anhydride and 300 g of toluene were dispersed in a ball mill for 4 hours to prepare a photosensitive layer-formed product, which was then subjected to a conductive treated paper. It was applied with a wire bar so that the dry adhesion amount was 25 g / m ^2, and dried at 110 ° C. for 1 minute. Then, in the dark, at 20 ° C and 65% RH
Each electrophotographic photoreceptor was prepared by being left for 24 hours.

Comparative Example D In Example 34, 6.5 g of resin [A-1] and resin [B-
16] A photosensitive material was produced in the same manner as in Example 34 except that 6.5 g of resin [R-3] and 33.5 g of resin [R-4] were used instead of 33.5 g.

As in Example 1, each characteristic of each photosensitive material was examined. The results are summarized in Table 7 below.

In the above measurement, the same operation as in Example 1 was performed, except that the following operation was performed for the electrostatic characteristics and the image capturing property.

Note 7) Method for measuring E _1/10 and E _1/100 of electrostatic characteristics After charging the surface of the photoconductive layer to −400 V by corona discharge, irradiating the surface of the photoconductive layer with visible light having an illuminance of 2.0 lux. The time required for the surface potential (V ₁₀ ) to decay to 1/10 or 1/100 is determined, and the exposure amount E _1/10 or E _1/100 (lux seconds) is calculated from this.

Note 8) Imaging characteristics After each photosensitive material is left for one day and night under the following environmental conditions, E is used with a fully automatic plate making machine EPL-404V (Fuji Photo Film Co., Ltd.).
A copy image (fog, image quality) obtained by making a plate using PL-T as a toner was visually evaluated. Environmental conditions at the time of imaging were 20 ° C. and 65% RH (I) and 30 ° C. and 80% RH (II). However, a copy original (that is, a copy original) was prepared by cutting and pasting another original.

In each photosensitive material, no difference was observed in the smoothness and strength of the photoconductive layer. However, in Comparative Example D, the value of the light sensitivity E _1/100 was particularly large in the electrostatic characteristics. The photosensitive material of the present invention has good electrostatic characteristics, and furthermore, the photosensitive material of Example 35 using the resin [A] having a specific substituent was used.
Was very good, and the value of E _1/100 was particularly small.

Investigation of the actual imaging performance revealed that in Comparative Example D, in addition to the original as a copy image, the frame of the cut and pasted portion (that is, the pasted trace) was recognized as background stain in the non-image portion. However, in each case of the present invention, clear images without background stains were obtained.

Further, when these were subjected to desensitization processing as an offset printing original plate and then printed, 10,000 sheets of clear images having no background stain were obtained in any of the present invention. However, in Comparative Example D, the sticking marks were not removed even by the desensitizing treatment, and were generated from the printed material.

As described above, only the photosensitive material of the present invention was able to give good characteristics.

Examples 36 to 49 In Example 34, 6.5 g of resin [A-1] and resin [B
-16] instead of 33.5 g, use the resin [A] 6.5 g shown in Table 8 below.
Each photosensitive material was produced in the same manner as in Example 34 except that 33.5 g of the resin [B] was used.

All photosensitive materials of the present invention are chargeable, dark charge retention,
Excellent light sensitivity, real copy image is high temperature and humidity (30 ℃, 80%
Even under severe conditions (RH), a clear image was obtained without occurrence of ground fogging or fine line skipping.

Further, when printing was performed as an offset master plate, a printed matter of clear image quality free of background stain was obtained even after printing 10,000 sheets.

Example 50 8 g of resin [A-21] and resin [B-14] 28 having the following structure
g, zinc oxide 200g, uranine 0.02g, rose bengal 0.04
g, bromophenol blue 0.03 g, phthalic anhydride 0.20 g
And a mixture of 300 g of toluene were dispersed in a ball mill for 4 hours, 3.5 g of 1,3-xylylene diisocyanate was further added, and the mixture was further dispersed in a ball mill for 10 minutes.

This was applied to a conductive treated paper with a wire bar so that the dry adhesion amount was 18 g / m ^2, and heated at 110 ° C. for 30 seconds.
Thereafter, the mixture was heated at 120 ° C. for 2 hours. Then in dark place at 20 ℃, 65% R
Each electrophotographic photoreceptor was prepared by being left under H condition for 24 hours.

The photosensitive materials of the present invention are all excellent in chargeability, dark charge retention, and photosensitivity.
(80 ° C, 80% RH), a clear image with no ground fog was obtained.

Further, when this was used as an offset master plate and printing was performed on 10,000 sheets, printed matter of clear image quality was obtained.

(Effects of the Invention) According to the present invention, an electrophotographic photoreceptor having excellent electrostatic characteristics (particularly electrostatic characteristics under severe conditions), a clear and high-quality image, and further excellent mechanical strength. Can be obtained. In particular, it is effective for a scanning exposure method using semiconductor racer light.

By using the repeating unit containing the specific methacrylate component represented by the formula (Ia) or (Ib) in the resin of the present invention, the electrostatic properties are further improved.

Claims (3)

(57) [Claims] An electrophotographic photoreceptor having a photoconductive layer containing at least an inorganic photoconductive material and a binder resin, wherein the binder resin is at least one of the following resins [A]:
An electrophotographic photosensitive member comprising a seed and at least one kind of resin [B]. Resin (A); 1 × 10 ³ has a weight average molecular weight of ~2 × 10 ^4, -PO ₃ H
₂ group, -COOH group, -SO ₃ H groups, phenolic OH groups, R represents a hydrocarbon group or an -OR 'group (R' is a hydrocarbon group) and A comprises at least one polymer component containing at least one acidic group selected from cyclic acid anhydride-containing groups. An AB block copolymer comprising a block and a B block containing at least a polymer component represented by the following general formula (I). General formula (I) [In the formula (I), R ₁ represents a hydrocarbon group. ] Resin [B], at least one and -COOH groups of the polymer component represented by the following general formula (IV a) and _{(IV b), -PO 3 H} 2 group, -SO ₃
H group, -OH group, (R ₀ represents the same content as R above), at least one polymer component containing at least one component containing at least one polar group selected from the group consisting of —CHO group and cyclic acid anhydride-containing group And a monofunctional macromonomer (MB) having a weight average molecular weight of 2 × 10 ⁴ or less formed by bonding a polymerizable double bond group represented by the following general formula (III) to only one end of a polymer main chain containing ) at least comprising a weight-average molecular weight and a monomer represented by the following general formula (V) 5 × 10 ⁴ ~
1 × 10 ⁶ copolymer. General formula (III) Wherein (III), X ₀ is -COO -, - OCO -, - CH 2 OCO-,
_{-CH 2 COO -, - O -} , - SO 2 -, - CO -, - CONHCOO-,
−CONHCONH−, Wherein R ₃₁ represents a hydrogen atom or a hydrocarbon group. c ₁ and c ₂ may be the same or different, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, -COO-Z ₄
Or —COO—Z ₄ via a hydrocarbon (Z ₄ each represents a hydrogen atom or a hydrocarbon group which may be substituted). General formula (IVa) General formula (IV b) Wherein (IV a) or (IV b), X ₁ represents the same content as X ₀ in formula (III). Q ₁ represents an aliphatic group having 1 to 18 carbon atoms or an aromatic group having 6 to 12 carbon atoms. d ₁ and d ₂ may be the same or different from each other, and represent the same contents as c ₁ and c ₂ in the formula (III). Q ₀ is -CN, -CONH ₂ or The expressed, Y represents a hydrogen atom, a halogen atom, an alkoxy group or -COOZ ₅ (Z ₅ represents an alkyl group, an aralkyl group or an aryl group). General formula (V) [In formula (V), X ₂ represents the same content as X ₁ in formula (IVa), and Q ₂ represents the same content as Q ₁ in formula (IV a).
e ₁ and e ₂ may be the same or different and represent the same contents as c ₁ and c _{2 in} formula (III). ] 2. The AB block copolymer, wherein the B block contains at least 30% by weight of at least one repeating unit selected from the following formulas (Ia) and (Ib). The electrophotographic photosensitive member according to claim 1. General formula (Ia) General formula (Ib) [In formula (Ia) or (Ib), M ₁ and M ₂ are independently of each other;
Each represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a chlorine atom, a bromine atom, -COZ ₂ or -COOZ ₂ (Z ₂ are each carbon atoms 1
~ 10 hydrocarbon groups). However, M ₁ and M ₂ are never both represent a hydrogen atom. L ₁ and L ₂ each connect -COO- and a benzene ring,
It represents a single bond or a linking group having 1 to 4 linking atoms. ] 3. The resin [B] comprises a —PO ₃ H ₂ group, a —SO ₃ H group,
-COOH group, -OH group, (R ₀ 'represents the same content as R) and a resin comprising at least one polar group selected from cyclic acid anhydride-containing groups bonded to one end of the main chain of the copolymer. The electrophotographic photosensitive member according to (1) or (2).