JP2003057857A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor containing a resin for a photoreceptor with excellent mechanical stability, easily soluble in a solvent of an applied liquid, excellent in applied liquid retaining stability and further excellent in electrical property, especially in response. SOLUTION: The electrophotographic photoreceptor provided with a photosensitive layer on a conductive supporting body, is characterized by having a binding resin of the photosensitive layer with a polyarylate structure expressed by a general formula (1), (in the general formula (1), X is at least two kinds selected from groups expressed by general formulas (2), (3) and (4) and in the general formulas (2), (3) and (4), R<1> -R<24> express a hydrogen atom, an alkyl group, an alkoxy group and so on and Y<1> -Y<3> express a single bond, -O-, -S-, -CH2 - and so on).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic photosensitive member having a photosensitive layer formed on a conductive support. More specifically, the present invention relates to an electrophotographic photoreceptor containing a resin for an electrophotographic photoreceptor having excellent solubility in preparing a coating solution for forming a photosensitive layer, excellent storage stability of the coating solution, and excellent electric responsiveness. It is.

[0002]

2. Description of the Related Art In recent years, electrophotographic technology has been widely used and applied not only in the field of copying machines but also in the field of various printers because of its immediacy and high-quality images. Photoconductors, which are the core of electrophotographic technology, have been formed from conventional inorganic photoconductors such as selenium, arsenic-selenium alloy, cadmium sulfide, and zinc oxide as photoconductive materials. A photoreceptor using an organic photoconductive material, which has advantages such as easiness and easy production, has been developed.

As the organic photoreceptor, a so-called dispersion type photoreceptor in which a photoconductive fine powder is dispersed in a binder resin, and a laminated type photoreceptor in which a charge generation layer and a charge transfer layer are laminated are known. The laminated photoreceptor can be obtained by combining a highly efficient charge generating substance and a charge transfer substance to obtain a highly sensitive photoreceptor, a wide material selection range and a highly safe photoreceptor, and coating. Since it is highly productive and relatively advantageous in terms of cost, it is highly likely to become the mainstream of the photoreceptor and has been developed and put into practical use.

The electrophotographic photosensitive member is repeatedly used in an electrophotographic process, that is, in a cycle of charging, exposure, development, transfer, cleaning, charge elimination, and the like. Such deterioration includes, for example, strong oxidizing ozone and NOx generated from a corona charger commonly used as a charger, causing chemical damage to the photosensitive layer, and carrier (current) generated by image exposure. Is chemically and electrically deteriorated due to, for example, the flow of the compound in the photosensitive layer, the charge removal light, and the decomposition of the photosensitive layer composition due to external light.
Further, other deteriorations include mechanical deterioration such as abrasion or scratches on the surface of the photosensitive layer due to contact with cleaning blades, magnetic brushes or the like, contact with a developer or paper, and peeling of the film. In particular, such damages on the surface of the photosensitive layer tend to appear on the copy image and directly impair the image quality, which is a major factor limiting the life of the photosensitive member. That is, in order to develop a photoreceptor having a long life, it is essential to increase the electrical and chemical durability as well as the mechanical strength.

In general, in the case of a laminated type photoreceptor, it is the charge transfer layer that receives such a load. The charge transfer layer is usually composed of a binder resin and a charge transfer material, and it is the binder resin that substantially determines the strength.However, the doping amount of the charge transfer material is considerably large, so that sufficient mechanical strength has been reached. Not in. Also, with the increasing demand for high-speed printing,
Materials for higher speed electrophotographic processes are required. In this case, the photoreceptor must have high sensitivity and long life, and also have high responsiveness because the time from exposure to development is short. It is known that the responsivity of the photoreceptor is governed by the charge transfer layer, especially the charge transfer material, but also greatly depends on the binder resin.

[0006] Each layer constituting these electrophotographic photosensitive members is formed by dip coating, spray coating, nozzle coating, bar coating, roll coating, blade coating or the like on a support. In particular, as a method for forming the charge transfer layer, a known method such as coating as a coating solution obtained by dissolving a substance to be contained in the layer in a solvent is applied. In these current processes, a coating solution is prepared in advance and stored. Therefore, for the binder resin, the solvent used in the coating process,
Excellent solubility and stability of the coating solution after dissolution are also required.

Conventional binder resins for the charge transfer layer include vinyl polymers such as polymethyl methacrylate, polystyrene, and polyvinyl chloride, and copolymers thereof, polycarbonate, polyester, polysulfone, phenoxy, epoxy, and silicone resins. Thermoplastic resins and various thermosetting resins have been used. Among various binder resins, polycarbonate resins have relatively excellent performance, and various polycarbonate resins have been developed and put to practical use. For example, JP
JP-98-33232 discloses a bisphenol P-type polycarbonate, and JP-A-59-71057 discloses a bisphenol Z-type polycarbonate.
No. 9-184251 discloses a copolymer type polycarbonate of bisphenol P and bisphenol A,
JP-A-5-21478 discloses a polycarbonate copolymer having a bis (4-hydroxyphenyl) ketone type structure as a binder resin. However, conventional organic photoreceptors have drawbacks such as surface wear and surface damage due to practical loads such as development with toner, friction with paper, and friction with a cleaning member (blade). At present, the printing performance is limited in practical use.

On the other hand, JP-A-56-135844 discloses a technique of an electrophotographic photoreceptor using a polyarylate resin having the following structure, which is commercially available under the trade name "U-Polymer", as a binder. Among them, it is shown that the sensitivity is particularly excellent as compared with polycarbonate. JP-A-3-6567 discloses an electrophotographic photoreceptor characterized by containing a polyarylate copolymer having a structure using tetramethylbisphenol F and bisphenol A as a bisphenol component.

Japanese Patent Application Laid-Open No. 10-288845 discloses that the use of a polyarylate resin containing a bisphenol component having a specific structure as a binder resin improves the solution stability during the production of a photoreceptor. Japanese Unexamined Patent Publication No. 10-288846 discloses that an electrophotographic photosensitive member using a polyarylate resin having a specific kinematic viscosity range has excellent mechanical strength, particularly excellent abrasion resistance.

[0010]

However, when the currently used polycarbonate resin is used in an electrophotographic process, it is still insufficient in abrasion resistance, scratch resistance, responsiveness, adhesion to a substrate, and the like. Often. Further, in the commercially available polyarylate resin “U-Polymer”, although the abrasion resistance and the sensitivity were slightly improved, the stability of the coating solution was poor, and coating production was impossible. JP-A-3-6567
In the case of using a polyarylate copolymer having a structure using tetramethylbisphenol F and bisphenol A for the bisphenol component disclosed in Japanese Patent Application Publication, although mechanical properties are slightly improved, electrical properties, particularly, sensitivity and responsiveness are improved. However, sufficient performance has not been obtained.

Further, by using a polyarylate resin having a specific structure disclosed in JP-A-10-288845 and JP-A-10-288846, the solubility /
Although the solution stability and the mechanical strength are improved, the demand for high-speed printing has recently been increased, and the electrical characteristics, particularly the responsiveness, have been insufficient. Therefore, it is easily dissolved in the mechanical strength and the solvent of the coating solution and has excellent storage stability of the coating solution.
At present, there is a demand for a binder resin having excellent electrical properties, particularly excellent responsiveness.

[0012]

The inventors of the present invention have studied the binder resin used in the photosensitive layer in detail, and have found that a polyarylate resin obtained by polymerizing two or more monomers having a specific structure is used. By using it as a binder resin, it has high solubility in the coating liquid solvent and excellent storage stability of the coating liquid, and forms a good coated surface,
In addition, they have found that they have excellent electrical characteristics, especially responsiveness, and have reached the present invention.

That is, the present invention provides an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, wherein the binder resin of the photosensitive layer has a polyarylate structure represented by the following general formula (1). The gist is an electrophotographic photosensitive member.

[0014]

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In the general formula (1), X is the following general formula (2):
At least two types selected from the group represented by (3) and (4).

[0016]

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[0017]

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[0018]

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In the general formulas (2), (3) and (4), R ¹
To R ²⁴ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, an alkoxy group having 1 to 10 carbon atoms which may have a substituent, a halogen atom, It represents a halogenated alkyl group or an aromatic group having 6 to 20 carbon atoms which may have a substituent. Y ^{1 to} Y ³ may be the same or different, and each is a single bond, a divalent organic group represented by the general formula (5), —O—, —S—, —CO—, and —.
SO ₂ — or — (CH ₂ ) _s — (s is an integer of 1 to 5).

[0020]

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In the general formula (5), R^{twenty five}And R²⁹Each
Each independently having 1 to 10 carbon atoms which may have a substituent;
Alkyl group, optionally having 1 to 10 carbon atoms
Alkoxy group, halogen atom, halogenated alkyl
Group, an aromatic group having 6 to 20 carbon atoms which may have a substituent
Represents a group. Also R²⁶, R²⁷And R²⁸Are independent
A hydrogen atom, an optionally substituted carbon number of 1 to 1
0 alkyl group, 1 to 1 carbon atoms which may have a substituent
10 alkoxy groups, halogen atoms, halogenated alkyl
, An aromatic group having 6 to 20 carbon atoms which may have a substituent
Represents a group. Also R ^{twenty five}And R²⁶, R²⁷And R²⁸Are tied to each other
They may combine to form a ring. t is an integer of 0 or more;
u is an integer of 0 to 4.

The structure represented by the following general formula (6) in the general formula (1) is at least one selected from the structures represented by the following general formula (7).

[0023]

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[0024]

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In the general formula (7), a and b are 1 ≧ a ≧
0, 1 ≧ b ≧ 0 and a + b = 1.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. <Resin for Electrophotographic Photoreceptor> The electrophotographic photoreceptor of the present invention comprises:
The binder resin of the photosensitive layer has a polyarylate structure represented by the general formula (1).

Next, specific examples of the polyarylate structure in claim 1 will be described, but the present invention is not limited to these specific examples. The structure represented by the general formula (6) in the general formula (1) is a residue derived from an aromatic dicarboxylic acid component used when producing the polyarylate resin used in the present invention.

As the aromatic dicarboxylic acid component, a structure represented by the general formula (7) is used. Specifically, terephthalic acid derivatives and isophthalic acid derivatives such as terephthalic acid chloride and isophthalic acid chloride are used. In the general formula (7), a and b are 1 ≧ a / (a
+ B) is a value satisfying ≧ 0, preferably 1 ≧ a /
(A + b) ≧ 0.5, particularly preferably 1 ≧ a /
This value satisfies (a + b) ≧ 0.7. a / (a +
When the value of b) is small, the electrical characteristics of the photoconductor tend to be poor, which is not preferable.

X, which is a structural unit in the general formula (1), is at least two types selected from the group represented by the general formulas (2), (3) and (4). It is a residue derived from the p, p'-form, o, p'-form, or o, o'-form of the biphenol component or the bisphenol component used when producing the polyarylate resin used in the present invention. These may be selected from regioisomers having the same descriptive formula or may be selected from different isomers.

In the general formulas (2), (3) and (4), R ^{1 to} R ²⁴ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent or a substituent. Optionally having 1 to 10 carbon atoms, an alkoxy group, a halogen atom, a halogenated alkyl group, and 6 carbon atoms which may have a substituent
~ 20 aromatic groups are shown. Examples of the alkyl group include:
Methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group,
Examples include a tert-butyl group, an n-pentyl group, a sec-pentyl group, and an n-hexyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, and an n-butoxy group. The halogen atom includes a chlorine atom, a bromine atom, a fluorine atom, and the like.
Examples of the halogenated alkyl group include a chloromethyl group, a dichloromethyl group, a trichloromethyl group, a trifluoromethyl group and the like. Examples of the aromatic group which may have a substituent include a phenyl group, a 4-methylphenyl group, and a naphthyl group. Among these, an alkyl group is preferred, and a methyl group is particularly preferred.

Each of Y ^{1 to} Y ³ may be the same or different and is a single bond, a divalent organic group represented by the following general formula (5), —O—, —S—, —CO—, or —. SO ₂ — or — (CH ₂ ) _s — (s is an integer of 1 to 5). Among these - (CH _{2) s} -, and the general formula (5) a divalent organic group represented by a single bond are preferred, particularly -CH ₂ - are preferred.

In the general formula (5), R ²⁵ and R ²⁹ each independently represent an alkyl group having 1 to 10 carbon atoms which may have a substituent or 1 carbon atom which may have a substituent. -10
An alkoxy group, a halogen atom, a halogenated alkyl group, and an aromatic group having 6 to 20 carbon atoms which may have a substituent. R ²⁶ , R ²⁷ and R ²⁸ each independently represent a hydrogen atom or an optionally substituted carbon atom of 1 to 1;
0 alkyl group, 1 to 1 carbon atoms which may have a substituent
It represents a 10 alkoxy group, a halogen atom, a halogenated alkyl group, or an optionally substituted aromatic group having 6 to 20 carbon atoms. Specific examples of these are the same as described above. R ²⁵ and R ²⁶ and R ²⁷ and R ²⁸ may be bonded to each other to form a ring. Of these, preferably, R ²⁵ and R ²⁹ are each independently an alkyl group having 1 to 6 carbon atoms, and R ²⁶ , R ²⁷ and R ²⁸ are each independently a hydrogen atom, a carbon atom having 1 to 6 carbon atoms. R ²⁵ and R ²⁶ , and R ²⁷ and R ²⁸ may be bonded to each other to form a ring. t is an integer of 0 or more, preferably 0
Or 1, particularly preferably t = 0. u is 0
-4.

Specific examples of the biphenol component having the structure represented by the general formula (2) or the bisphenol component include 4,4′-biphenol and 3,3 ′.
-Dimethyl-4,4'-dihydroxy-1,1'-biphenyl [3,3'-dimethyl-{(1,1'-bi-phenyl) -4,4'-diol}], 3,3'- Di- (t
-Butyl) -4,4'-dihydroxy-1,1'-biphenyl [3,3'-di- (t-butyl)-{(1,1 '
-Bi-phenyl) -4,4'-diol {], 3,
3 ′, 5,5′-tetramethyl-4,4′-dihydroxy-1,1′-biphenyl [3,3 ′, 5,5′-tetramethyl-｛(1,1′-bi-phenyl) — 4,4'-
Diol｝], 3,3 ′, 5,5′-tetra- (t-butyl) -4,4′-dihydroxy-1,1′-biphenyl [3,3 ′, 5,5′-tetra- (t -Butyl)-
{(1,1′-bi-phenyl) -4,4′-diol}], 2,2 ′, 3,3 ′, 5,5′-hexamethyl
-4,4'-dihydroxy-1,1'-biphenyl
[2,2 ', 3,3', 5,5'-hexamethyl-
Biphenol components such as {(1,1′-bi-phenyl) -4,4′-diol}], bis- (4-hydroxyphenyl) methane (BPF), bis- (4-hydroxy-3-methylphenyl) Methane, 1,1-bis- (4-
(Hydroxyphenyl) ethane (BPE), 1,1-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) propane (BPA),
2,2-bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl) pentane, 2,2- Bis- (4-hydroxyphenyl) -3-methylbutane, 2,2-bis- (4-hydroxyphenyl) hexane, 2,2-bis- (4-hydroxyphenyl) -4-methylpentane, 1,1-bis −
(4-hydroxyphenyl) cyclopentane, 1,1-
Bis- (4-hydroxyphenyl) cyclohexane (B
PZ), bis- (3-phenyl-4-hydroxyphenyl) methane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) ethane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) ) Propane, 2,2-bis- (3-phenyl-4-hydroxyphenyl) propane (BPQ), 1,1-bis- (4-hydroxy-3-methylphenyl) ethane (Ce), 2,2-bis − (4-
Hydroxy-3-methylphenyl) propane (BP
C), 2,2-bis- (4-hydroxy-3-ethylphenyl) propane, 2,2-bis- (4-hydroxy-
3-isopropylphenyl) propane, 2,2-bis-
(4-hydroxy-3-sec-butylphenyl) propane, 1,1-bis- (4-hydroxy-3,5-dimethylphenyl) ethane (Xe), 2,2-bis- (4-
Hydroxy-3,5-dimethylphenyl) propane (T
ma), 1,1-bis- (4-hydroxy-3,6-dimethylphenyl) ethane, bis- (4-hydroxy-
2,3,5-trimethylphenyl) methane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) ethane, 2,2-bis- (4-hydroxy-2,
3,5-trimethylphenyl) propane, bis- (4-
Hydroxy-2,3,5-trimethylphenyl) phenylmethane, 1,1-bis- (4-hydroxy-2,3,
5-trimethylphenyl) phenylethane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) cyclohexane, bis (4-hydroxyphenyl) phenylmethane, 1,1-bis- (4- (Hydroxyphenyl) -1-phenylethane (BPP), 1,1-
Bis- (4-hydroxyphenyl) -1-phenylpropane, bis- (4-hydroxyphenyl) diphenylmethane, bis- (4-hydroxyphenyl) dibenzylmethane, 4,4 ′-[1,4-phenylenebis (1 -Methylethylidene)] bis- [phenol], 4,4 '-[1,
4-phenylenebismethylene] bis- [phenol],
4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bis- [2,6-dimethylphenol], 4,
4 '-[1,4-phenylenebismethylene] bis- [2
6-dimethylphenol], 4,4 '-[1,4-phenylenebismethylene] bis- [2,3,6-trimethylphenol], 4,4'-[1,4-phenylenebis (1-methylethylidene) )] Bis- [2,3,6-trimethylphenol], 4,4 ′-[1,3-phenylenebis (1-methylethylidene)] bis- [2,3,6-trimethylphenol], 4,4 '-Dihydroxydiphenyl ether (BPO), 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfide,
3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxydiphenyl ether, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxydiphenylsulfone, 3,3 ′, 5 5'-tetramethyl-4,4'-dihydroxydiphenyl sulfide, phenolphthalein, 4,4 '-[1,4-phenylenebis (1-methylvinylidene)] bisphenol, 4,4'-[1,4- And bisphenol components such as phenylenebis (1-methylvinylidene)] bis [2-methylphenol].

A preferred compound among these is bis-
(4-hydroxyphenyl) methane (BPF), bis-
(4-hydroxy-3-methylphenyl) methane, 1,
1-bis- (4-hydroxyphenyl) ethane (BP
E) and bisphenol components such as 2,2-bis- (4-hydroxyphenyl) propane (BPA). Among them, bis- (4-hydroxyphenyl)
Methane is particularly preferred.

Specific examples of the biphenol component or the bisphenol component having the structure represented by the general formula (3) include 2,4'-biphenol and 3,3'-dimethyl-
2,4′-dihydroxy-1,1′-biphenyl [3,
3′-dimethyl-｛(1,1′-bi-phenyl) -2,
4'-diol}], 3,3'-di- (t-butyl)-
2,4′-dihydroxy-1,1′-biphenyl [3,
Biphenol components such as 3′-di- (t-butyl)-{(1,1′-bi-phenyl) -2,4′-diol}],
(2-hydroxyphenyl) (4-hydroxyphenyl) methane, (2-hydroxy-5-methylphenyl)
(4-hydroxy-3-methylphenyl) methane, 1,
1- (2-hydroxyphenyl) (4-hydroxyphenyl) ethane, 2,2- (2-hydroxyphenyl)
(4-hydroxyphenyl) propane, 1,1- (2-
And bisphenol components such as (hydroxyphenyl) (4-hydroxyphenyl) propane. Among them, (2-hydroxyphenyl) (4-hydroxyphenyl) methane and 2,2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane are preferable, and (2-hydroxyphenyl) (4-hydroxyphenyl) is preferable. ) Methane is particularly preferred.

Specific examples of the biphenol component or the bisphenol component having the structure represented by the general formula (4) include 2,2'-biphenol and 3,3'-dimethyl-
2,2′-dihydroxy-1,1′-biphenyl [3,
3′-dimethyl-｛(1,1′-bi-phenyl) -2,
2'-diol}], 3,3'-di- (t-butyl)-
2,2′-dihydroxy-1,1′-biphenyl [3,
Biphenol components such as 3′-di- (t-butyl)-{(1,1′-bi-phenyl) -2,2′-diol}], bis- (2-hydroxyphenyl) methane, 1,1
-Bis- (2-hydroxyphenyl) ethane, 2,2-
Bis (2-hydroxyphenyl) propane, 1,1-bis- (2-hydroxyphenyl) propane, bis- (2
-Hydroxy-5-methylphenyl) methane, bis-
(2-hydroxy-3-methylphenyl) methane, 1,
1-bis- (2-hydroxy-4-phenyl) ethane,
Bis- (2-hydroxy-3,5-dimethylphenol) methane, bis- (2-hydroxy-3,6-dimethylphenol) methane, 2,2-bis- (2-hydroxy-3,5-dimethylphenol) And bisphenol components such as propane. Among these, bis-
(2-hydroxyphenyl) methane, 2,2-bis (2
-Hydroxyphenyl) propane and the like are preferable, and bis- (2-hydroxyphenyl) methane is particularly preferable.

<Method for Producing Resin for Electrophotographic Photoreceptor> As a method for producing the resin for an electrophotographic photoreceptor of the present invention, a known polymerization method can be used. For example, an interfacial polymerization method, a melt polymerization method, a solution polymerization method and the like can be mentioned. For example, in the case of production by an interfacial polymerization method, a solution in which a bisphenol component is dissolved in an aqueous alkaline solution is mixed with a solution of a halogenated hydrocarbon in which an aromatic dicarboxylic acid chloride component is dissolved. In this case, a quaternary ammonium salt or a quaternary phosphonium salt can be used as a catalyst.
The polymerization temperature is preferably in the range of 0 to 40 ° C, and the polymerization time is preferably in the range of 2 to 12 hours from the viewpoint of productivity. After polymerization,
The desired resin can be obtained by separating the aqueous phase and the organic phase, and washing and collecting the polymer dissolved in the organic phase by a known method.

The alkaline component used here is:
Examples include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. The amount of the alkali used is as follows: 1. The amount of the phenolic hydroxyl group contained in the reaction system.
A range of 01 to 3 equivalents is preferred. Further, as the halogenated hydrocarbon used herein, dichloromethane,
Chloroform, 1,2-dichloroethane, trichloroethane, tetrachloroethane, dichlorobenzene and the like can be mentioned.

Examples of the quaternary ammonium salt or quaternary phosphonium salt used as a catalyst include salts of tertiary alkylamines such as tributylamine and trioctylamine with hydrochloric acid, bromic acid and iodic acid, benzyltriethylammonium chloride, benzyltrimethylamine and the like. Ammonium chloride, benzyltributylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium bromide, trioctylmethylammonium chloride, tetrabutylphosphonium bromide, triethyloctadecylphosphonium bromide, N-laurylpyridinium chloride, laurylpicolinium chloride, etc. No.

In the polymerization, phenol, o, m, p-cresol, o, m, p-ethylphenol, o, m, p-propylphenol,
alkylphenols such as o, m, p-tert-butylphenol, pentylphenol, hexylphenol, octylphenol, nonylphenol and 2,6-dimethylphenol derivatives; monofunctional phenols such as o, m, p-phenylphenol; Monofunctional acid halides such as chloride, butyric acid chloride, octylic acid chloride, benzoyl chloride, benzenesulfonyl chloride, benzenesulfinyl chloride, sulfinyl chloride, benzenephosphonyl chloride and substituted products thereof may be present.

In the polyarylate resin comprising a repeating unit having the structure represented by the general formula (1), groups present at the molecular chain terminals, such as the above-mentioned molecular weight modifier, are not included in the repeating unit. General formula (1) of the present invention
Has a viscosity average molecular weight of 8,000 to 300,000, preferably 15,000 to 100,000, more preferably 20,000 to 50,000. When the viscosity average molecular weight is less than 10,000, the mechanical strength of the resin is lowered and is not practical, and when the viscosity average molecular weight is 300,000 or more,
When the photosensitive layer is formed on a conductive support, it is difficult to apply the photosensitive layer to an appropriate thickness.

The polyarylate resin of the present invention can be mixed with other resins and used for an electrophotographic photosensitive member. Other resins mixed here include polymethyl methacrylate, polystyrene, vinyl polymers such as polyvinyl chloride, and copolymers thereof, polycarbonate,
Polyester, polysulfone, phenoxy, epoxy,
Examples include thermoplastic resins such as silicone resins and various thermosetting resins. Among these resins, polycarbonate resins are preferred.

<Electrophotographic Photoreceptor> The resin of the present invention described above is used in an electrophotographic photoreceptor, and is used as a binder resin in a photosensitive layer provided on a conductive support of the photoreceptor. Examples of the conductive support include a metal material such as aluminum, aluminum alloy, stainless steel, copper, and nickel, a metal, carbon, and a resin material to which conductivity is added by adding a conductive powder such as tin oxide, aluminum, or the like. Resins, glass, paper, and the like, in which a conductive material such as nickel or ITO (indium tin oxide alloy) is deposited or applied on the surface thereof, are mainly used. As the form, a drum shape, a sheet shape, a belt shape or the like is used. A conductive material having an appropriate resistance value may be applied on a conductive support made of a metal material for controlling conductivity and surface properties and for covering defects.

When a metal material such as an aluminum alloy is used as the conductive support, it may be used after anodizing treatment, chemical conversion treatment and the like. When the anodic oxidation treatment is performed, it is desirable to perform the sealing treatment by a known method. The surface of the support may be smooth, or may be roughened by using a special cutting method or performing a polishing treatment. Further, the support may be roughened by mixing particles having an appropriate particle diameter with the material constituting the support.

An undercoat layer may be provided between the conductive support and the photosensitive layer in order to improve adhesion and blocking properties. As the undercoat layer, a resin, a material in which particles of a metal oxide or the like are dispersed in the resin, or the like is used. Examples of the metal oxide particles used for the undercoat layer include metal oxide particles containing one kind of metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, iron oxide, calcium titanate, and titanium. Examples include metal oxide particles containing a plurality of metal elements such as strontium acid and barium titanate. One type of particles may be used alone, or a plurality of types of particles may be mixed and used. Among these metal oxide particles, titanium oxide and aluminum oxide are preferable, and titanium oxide is particularly preferable. The surface of the titanium oxide particles may be treated with an inorganic substance such as tin oxide, aluminum oxide, antimony oxide, zirconium oxide, or silicon oxide, or an organic substance such as stearic acid, polyol, or silicone. As the crystal form of the titanium oxide particles, any of rutile, anatase, Brookite, and amorphous can be used. A plurality of crystals may be included.

As the particle size of the metal oxide particles, various types can be used. Among them, from the viewpoint of the characteristics and the stability of the liquid, the average primary particle size is 10 nm to 100 nm.
The following is preferable, and particularly preferable is 10 nm or more and 25
nm or less. The undercoat layer is preferably formed in a form in which metal oxide particles are dispersed in a binder resin. As the binder resin used for the undercoat layer, phenoxy, epoxy, polyvinylpyrrolidone, polyvinyl alcohol, casein, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide, polyamide, and the like alone or together with a curing agent are cured. Among them, alcohol-soluble copolymerized polyamides, modified polyamides and the like are preferable because they show good dispersibility and coatability.

The addition ratio of the inorganic particles to the binder resin can be arbitrarily selected, but is preferably used in the range of 10% by weight to 500% by weight in view of the stability of the dispersion and the applicability. The thickness of the undercoat layer can be arbitrarily selected,
The thickness is preferably from 0.1 μm to 20 μm from the characteristics of the photoreceptor and the applicability. A known antioxidant may be added to the undercoat layer.

The photosensitive layer formed on the conductive support may be a single layer type in which a charge generating substance and a charge transporting substance are dispersed in a binder resin, or a single layer type in which a charge generating substance is dispersed in a binder resin. Any of a stacked type including two layers of a charge generation layer formed and a charge transport layer in which a charge transport material is dispersed in a binder resin may be used. Examples of the charge generation material include selenium and its alloys, cadmium sulfide, other inorganic photoconductive materials, phthalocyanine pigments, azo pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, anthrone pigments, benzimidazole pigments and the like. Various photoconductive materials such as organic pigments can be used, and particularly preferred are organic pigments, furthermore, phthalocyanine pigments and azo pigments. These fine particles may be used, for example, polyester resin, polyvinyl acetate, polyacrylate, polymethacrylate, polyester, polycarbonate, polyvinyl acetoacetal, polyvinyl propional, polyvinyl butyral, phenoxy resin, epoxy resin, urethane resin, cellulose ester, cellulose ether. It is used in a form bound with various binder resins such as. The use ratio in this case is from 30 to 500 parts by weight with respect to 100 parts by weight of the binder resin, and the film thickness is usually 0.1 μm to 1 μm.
m, preferably 0.15 μm to 0.6 μm.

When a phthalocyanine compound is used as the charge generating substance, specifically, a metal-free phthalocyanine,
Metals such as copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, and germanium, or coordinated phthalocyanines such as oxides, halides, hydroxides, and alkoxides thereof are used. Especially sensitive X
Preferred are titanyl phthalocyanine, vanadyl phthalocyanine, chloroindium phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine, and the like, such as phthalocyanine, τ-type metal-free phthalocyanine, A-type, B-type, and D-type. In addition, among the crystal forms of titanyl phthalocyanine mentioned here, A type and B type are described in W.C. Heller
Et al. Respectively show phase I and phase II (Ze
It. Kristallogr. 159 (1982) 173), type A is what is known as a stable type. Type D has a diffraction angle 2θ ± 0.2 ° of 27.3 in powder X-ray diffraction using CuKα ray.
゜ is a crystal type characterized by showing a clear peak. The phthalocyanine compound may be a single compound or a mixture of several compounds. As the phthalocyanine compound or a mixed state that can be placed in a crystalline state here, the respective components may be mixed and used later, or the mixed state may be used in the manufacturing and processing steps of the phthalocyanine compound such as synthesis, pigmentation, and crystallization. It may be the one that has occurred. As such a treatment, an acid paste treatment, a grinding treatment, a solvent treatment and the like are known.

Examples of the charge transport material include aromatic nitro compounds such as 2,4,7-trinitrofluorenone; cyano compounds such as tetracyanoquinodimethane; electron-withdrawing materials such as quinones such as diphenoquinone; carbazole derivatives; Heterocyclic compounds such as indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, oxadiazole derivatives, pyrazoline derivatives, thiadiazole derivatives, aniline derivatives, hydrazone compounds, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine compounds, and the like An electron donating substance such as a compound in which a plurality of compounds are bonded or a polymer having a group consisting of these compounds in a main chain or a side chain is exemplified. Among these, carbazole derivatives, hydrazone derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives and those in which a plurality of these derivatives are bonded are preferable, and those in which a plurality of aromatic amine derivatives, stilbene derivatives, butadiene derivatives are bonded, are preferable. preferable.

Specifically, those having a structure represented by the following general formula (8) are preferably used.

[0052]

Embedded image

(In the general formula (8), Q is a single bond or divalent
An organic group of Ar¹~ Ar^FourAre independent of each other
Having an arylene group or a substituent
And a divalent heterocyclic group which may be substituted. m¹And m^TwoIs
Each independently represents 0 or 1, and m¹And m^TwoIs 0
In the case of Ar^FiveAnd Ar⁶Each independently represents a substituent
May have an alkyl group, may have a substituent
Aryl groups, or monovalent optionally substituted
Represents a heterocyclic group, m¹And m^TwoIs 1, when Ar ^FiveAnd
And Ar⁶May each independently have a substituent
Alkylene group, arylene optionally having substituent (s)
Group or a divalent heterocyclic group which may have a substituent
And R³⁰~ R³⁷Each independently has a substituent
Alkyl group which may be substituted, aryl which may have a substituent
Group, aralkyl group which may have a substituent, substituent
A monovalent heterocyclic group which may have
And n ¹~ N^FourAre each independently an integer from 0 to 4
You. Ar¹~ Ar⁶Combine with each other to form a ring structure
May be. ) In the general formula (8), R³⁰~ R³⁷Are independent
Alkyl group which may have a substituent,
Aryl group which may be substituted, which may have a substituent
An aralkyl group, a heterocyclic group which may have a substituent,
Or a hydrogen atom, and examples of the alkyl group include, for example,
Methyl, ethyl, propyl, isopropyl, butyl
Tyl, pentyl, hexyl, heptyl, cyclo
Pentyl group, cyclohexyl group and the like.
An alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group is particularly preferable.
Preferred.

As the aryl group, a phenyl group,
Examples thereof include a tolyl group, a xylyl group, a naphthyl group and a pyrenyl group, and an aryl group having 6 to 12 carbon atoms is preferable. Examples of the aralkyl group include a benzyl group and a phenethyl group, and an aralkyl group having 7 to 12 carbon atoms is preferable. The heterocyclic group is preferably an aromatic heterocyclic ring, such as a furyl group, a thienyl group, or a pyridyl group. A monocyclic aromatic heterocyclic ring is particularly preferable.

In the general formula (8), Ar ^{1 to} Ar ⁴ are each independently an arylene group which may have a substituent or a divalent heterocyclic group which may have a substituent. And m
¹ and m ² are each independently 0 or 1, and m ¹
And when m ² is 0, Ar ⁵ and Ar ⁶ are each independently an alkyl group optionally having a substituent, an aryl group optionally having a substituent, And when m ¹ and m ² are 1, each represents an alkylene group which may have a substituent, an arylene group which may have a substituent, or a substituent. Represents a divalent heterocyclic group which may be possessed. As the aryl group,
A phenyl group, a tolyl group, a xylyl group, a naphthyl group, a pyrenyl group and the like, and an aryl group having 6 to 14 carbon atoms is preferable; as an arylene group, a phenylene group, a naphthylene group and the like are preferable, and a phenylene group is preferable; As the monovalent heterocyclic group, an aromatic heterocyclic ring is preferable, and examples thereof include a furyl group, a thienyl group, and a pyridyl group. A monocyclic aromatic heterocyclic ring is particularly preferable; a divalent heterocyclic group Is preferably a heterocyclic ring having aromaticity, such as a pyridylene group and a thienylene group, and a monocyclic aromatic heterocyclic ring is particularly preferable.

Of these, the most preferred is Ar ¹
And Ar ² are phenylene groups, and Ar ⁵ and Ar ⁶ are phenyl groups. Of the groups represented by R ^{30 to} R ³⁷ and Ar ^{1 to} Ar ⁶ , the alkyl group, the aryl group, the aralkyl group, and the heterocyclic group may further have a substituent. A nitro group; a hydroxyl group; a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom and an iodine atom; a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an s-butyl group and a t-group. Alkyl groups such as butyl group, pentyl group, hexyl group, cyclopentyl group and cyclohexyl group; alkoxy groups such as methoxy group, ethoxy group and propyloxy group; alkylthio groups such as methylthio group and ethylthio group; vinyl groups and allyl group Alkenyl group; aralkyl group such as benzyl group, naphthylmethyl group and phenethyl group; aryloxy group such as phenoxy group and toloxy group; A ziroxy group,
Arylalkoxy groups such as phenethyloxy group; aryl groups such as phenyl group and naphthyl group; arylvinyl groups such as styryl group and naphthylvinyl group; acyl groups such as acetyl group and benzoyl group; dialkyl groups such as dimethylamino group and diethylamino group Amino group; diarylamino group such as diphenylamino group, dinaphthylamino group; diaralkylamino group such as dibenzylamino group and diphenethylamino group; diheterocyclic amino group such as dipyridylamino group and dithienylamino group; diallyl Examples include an amino group and a substituted amino group such as a di-substituted amino group obtained by combining the above-mentioned amino group substituents.

Further, these substituents are bonded to each other,
A cyclic hydrocarbon group or a heterocyclic group may be formed via a single bond, a methylene group, an ethylene group, a carbonyl group, a vinylidene group, an ethylenylene group, or the like. Among these, preferred substituents include a halogen atom, a cyano group, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylthio group having 1 to 6 carbon atoms, and an alkylthio group having 6 to 12 carbon atoms. An aryloxy group, an arylthio group having 6 to 12 carbon atoms, a dialkylamino group having 2 to 8 carbon atoms, a halogen atom, an alkyl group having 1 to 6 carbon atoms, and a phenyl group are more preferable, and a methyl group and a phenyl group are preferable. Particularly preferred.

In the general formula (8), n ^{1 to} n ⁴ each independently represent an integer of 0 to 4, preferably 0 to 2, and most preferably 1. m ¹ and m ² represent 0 or 1, and 0 is preferred.
In the general formula (8), Q represents a direct bond or a divalent residue, and a preferable divalent residue is a group 16 atom, an alkylene group which may have a substituent, or a substituent. An arylene group which may have a cycloalkylidene group which may have a substituent, or a group in which these are bonded to each other, for example, [—O
-A-O-], [-A-O-A-], [-S-A-S-],
[-AA-] and the like (provided that A represents an arylene group which may have a substituent or an alkylene group which may have a substituent).

As the alkylene group constituting Q, those having 1 to 6 carbon atoms are preferable, and a methylene group and an ethylene group are particularly preferable. The cycloalkylidene group preferably has 5 to 8 carbon atoms, and more preferably a cyclopentylidene group and a cyclohexylidene group. As the arylene group, one having 6 to 14 carbon atoms is preferable, and a phenylene group and a naphthylene group are particularly preferable.

The alkylene group, arylene group and cycloalkylidene group may have a substituent.
Preferred substituents include a hydroxyl group, a nitro group, a cyano group, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 1 to 6 carbon atoms, and an aryl group having 6 to 14 carbon atoms. These charge transporting substances may be used alone or in combination. The charge transport layer is formed in a state where these charge transport materials are bound to the binder resin. The charge transport layer may be composed of a single layer, or may be a layer in which a plurality of layers having different constituent components or composition ratios are stacked.

The ratio between the binder resin and the charge transport material is
Usually, 30 to 20 parts by weight based on 100 parts by weight of the binder resin.
0 parts by weight, preferably in the range of 40 to 150 parts by weight. The thickness is generally 5 to 50 μm, preferably 1 to 50 μm.
It is preferably from 0 to 45 μm. The charge transport layer has a well-known plasticizer, an antioxidant, an ultraviolet absorber, and an electron-attracting property in order to improve film formability, flexibility, coating properties, stain resistance, gas resistance, light resistance, and the like. Additives such as compounds and leveling agents may be included.

Examples of the antioxidant include a hindered phenol compound and a hindered amine compound. In the case of the dispersion type photosensitive layer, the above-mentioned charge generating substance is dispersed in the charge transporting medium having the above-described mixing ratio. In this case, the particle size of the charge generating substance needs to be sufficiently small, preferably 1 μm or less, more preferably 0.5 μm or less.
Used below μm. If the amount of the charge generating substance dispersed in the photosensitive layer is too small, sufficient sensitivity cannot be obtained. If the amount is too large, there are adverse effects such as a decrease in chargeability and a decrease in sensitivity. %, More preferably in the range of 1 to 20% by weight.

The thickness of the photosensitive layer is usually 5 to 50 μm, more preferably 10 to 45 μm. Also in this case, a known plasticizer for improving film forming property, flexibility, mechanical strength, etc., an additive for suppressing residual potential, a dispersing aid for improving dispersion stability, a coating property. Leveling agents, surfactants such as silicone oil,
Fluorine-based oil and other additives may be added.

A protective layer may be provided on the photosensitive layer for the purpose of preventing the photosensitive layer from being worn and preventing or reducing the deterioration of the photosensitive layer due to a discharge product or the like generated from a charger or the like. Also, in order to reduce the frictional resistance and wear of the photoconductor surface,
The surface layer may contain a fluorine resin, a silicone resin, or the like. Further, particles of these resins or particles of an inorganic compound may be included.

Each layer constituting the photoreceptor is formed by dip coating, spray coating, nozzle coating, bar coating, roll coating, blade coating or the like on a support. As a method for forming each layer, a known method such as sequentially applying a coating solution obtained by dissolving or dispersing a substance to be contained in a layer in a solvent can be applied.

Examples of the solvent or dispersion medium used for preparing the coating solution include alcohols such as methanol, ethanol, propanol and 2-methoxyethanol; ethers such as tetrahydrofuran, 1,4-dioxane and dimethoxyethane; Esters such as methyl formate and ethyl acetate, acetone, methyl ethyl ketone,
Ketones such as cyclohexanone, benzene, toluene,
Chlorination of aromatic hydrocarbons such as xylene, dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene, etc. Hydrocarbons, nitrogen-containing compounds such as n-butylamine, isopropanolamine, diethylamine, triethanolamine, ethylenediamine, triethylenediamine, aprotic polar such as acetonitrile, N-methylpyrrolidone, N, N-dimethylformamide, dimethylsulfoxide Examples thereof include solvents and the like, which are used alone or in combination of two or more.

In the preparation of the coating liquid or the dispersion, the solid content concentration is preferably 40% by weight or less, more preferably 40% by weight in the case of a single-layer type photosensitive layer and in the case of a charge-transporting layer of a laminated type photosensitive layer. 10 to 35% by weight, the viscosity is preferably 50 to 300 cps. In the case of the charge generation layer of the laminated photosensitive layer, the solid content concentration is preferably 15% by weight or less, more preferably 1 to 10% by weight, and the viscosity is Preferably, it is 0.1 to 10 cps.

Usually, after the transfer, a fixing process for fixing the developer to paper or the like is used, and as a fixing means, generally used heat fixing, pressure fixing and the like can be used. In addition to these processes, a process that is generally used, such as cleaning and static elimination, may be provided.

[0069]

The present invention will be described below in more detail with reference to Production Examples, Examples and Comparative Examples. The present invention is not limited to the manufacturing method according to the manufacturing example shown here. <Production of polyarylate resin> [Viscosity average molecular weight] A polyarylate resin was dissolved in dichloromethane to prepare a solution having a concentration C of 6.00 g / L.
The falling time t ₀ of the solvent (dichloromethane) is 136.16.
The falling time t of the sample solution was measured in a thermostatic water bath set at 20.0 ° C. using an Ubbelohde capillary viscometer for 2 seconds. The viscosity average molecular weight Mv was calculated according to the following equation.

A = 0.438 × η _sp +1 η _sp = t / t ₀ −1 b = 100 × η _sp / C C = 6.00 (g / L) η = b / a Mv = 3207 × η ¹ . ²⁰⁵ Production Example 1 (Production Method of Polyarylate Resin A of Example 1) Sodium hydroxide (15.62 g) and water (1122 ml) were weighed into a 1 L beaker, and stirred and dissolved while bubbling with nitrogen. There, benzyltriethylammonium chloride (0.1953 g), bis- (4-hydroxyphenyl) methane (10.30 g), (2-
After adding (hydroxyphenyl) (4-hydroxyphenyl) methane (14.13 g), bis- (2-hydroxyphenyl) methane (5.00 g) and pt-butylphenol (0.8833 g) and stirring, the alkali was added. The aqueous solution was transferred to a 2 L reaction vessel.

Separately, terephthalic acid chloride (30.4
8g) was dissolved in dichloromethane (561 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. 4 more
After continuing stirring for an hour, acetic acid (5.2 ml) was added and the mixture was stirred for 30 minutes. Thereafter, the stirring was stopped and the organic layer was separated. This organic layer was washed with a 0.1N aqueous sodium hydroxide solution (560 m
1) washing, then 0.1N hydrochloric acid (420ml)
The washing was performed twice, and the washing was further performed twice with water (420 ml). The washed organic layer was washed with methanol (3250
ml), the resulting precipitate was taken out by filtration, dried, and the structural units of (2), (3), (4) and (7) in the general formula (1) were as shown in Table 1 below. The desired polyarylate resin A was obtained. The viscosity average molecular weight of the obtained polyarylate resin A was 19,100.

Production Example 2 (Production method of polyarylate resin B of Example 2) Sodium hydroxide (7.82 g) and water (561 ml) were weighed into a 1 L beaker, and stirred and dissolved while bubbling with nitrogen. Therein, benzyltriethylammonium chloride (0.0973 g), bis- (4-hydroxyphenyl) methane (5.19 g), (2-hydroxyphenyl) (4-hydroxyphenyl) methane (7.11 g), bis- (2 -Hydroxyphenyl) methane (2.52 g) and pt-butylphenol (0.3334 g) were added and stirred, and then the aqueous alkali solution was transferred to a 1 L reaction tank.

Separately, terephthalic acid chloride (10.6
8 g) and isophthalic acid chloride (4.58 g) were dissolved in dichloromethane (281 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. After stirring was further continued for 4 hours, acetic acid (2.6 ml) was added and stirred for 30 minutes. Thereafter, the stirring was stopped and the organic layer was separated. This organic layer was washed with a 0.1 N aqueous sodium hydroxide solution (280 ml), then twice with 0.1 N hydrochloric acid (210 ml), and twice with water (210 ml). .

The washed organic layer was washed with methanol (1700 m
The precipitate obtained by pouring into l) was taken out by filtration, dried, and the structural units of (2), (3), (4) and (7) in the general formula (1) were as shown in Table 1 below. The desired polyarylate resin B was obtained. The viscosity average molecular weight of the obtained polyarylate resin B was 16,700. Production Example 3 (Production method of polyarylate resin C of Example 3) The same method as in Production Example 2 was used except that the amounts of terephthalic acid chloride (7.63 g) and isophthalic acid chloride (7.63 g) were changed. The target polyarylate resin C having the structural units of (2), (3), (4) and (7) in the general formula (1) as shown in Table 1 was obtained. The viscosity average molecular weight of the obtained polyarylate resin C was 14.9
00.

Production Example 4 (Production method of polyarylate resin D of Example 4) A method similar to that of Production Example 2 was used except that terephthalic acid chloride was not added and the amount of isophthalic acid chloride (15.26 g) was changed. And (2) in the general formula (1)
(3) The objective polyarylate resin D having the structural units of (4) and (7) as shown in Table 1 was obtained. The viscosity average molecular weight of the obtained polyarylate resin D was 12,500. Production Example 5 (Production method of polyarylate resin E of Example 5) Sodium hydroxide (9.40 g) and water (673 ml) were weighed into a 1 L beaker, and stirred and dissolved while bubbling with nitrogen. There, benzyltriethylammonium chloride (0.1164 g), (2-hydroxyphenyl) (4-hydroxyphenyl) methane (8.9)
5g), bis- (2-hydroxyphenyl) methane (8.95g) and pt-butylphenol (0.
After adding 2684 g) and stirring, the aqueous alkali solution was transferred to a 1 L reaction tank.

Separately, terephthalic acid chloride (9.17)
g) and isophthalic acid chloride (9.17 g) were dissolved in dichloromethane (337 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. After stirring was further continued for 4 hours, acetic acid (3.1 ml) was added and the mixture was stirred for 30 minutes.
Thereafter, the stirring was stopped and the organic layer was separated. The organic layer was washed with a 0.1 N aqueous sodium hydroxide solution (340 ml), then twice with 0.1 N hydrochloric acid (250 ml), and twice with water (250 ml). . The washed organic layer was poured into methanol (2250 ml), and the resulting precipitate was taken out by filtration, dried, and dried in the above general formula (1), (2), (3), (4) and (7).
The target polyarylate resin E whose structural unit was as shown in the following Table 1 was obtained. The viscosity average molecular weight of the obtained polyarylate resin E was 8,600.

Production Example 6 (Production Method of Polyarylate Resin F of Comparative Example 1) Sodium hydroxide (9.40 g) and water (673 ml) were weighed into a 1 L beaker, and dissolved by stirring while bubbling with nitrogen. There, benzyltriethylammonium chloride (0.1164 g), bis- (4-hydroxyphenyl) methane (17.89 g), and p-
After adding t-butylphenol (0.2684 g) and stirring, the aqueous alkali solution was transferred to a 1 L reaction tank.

Separately, terephthalic acid chloride (18.3)
4g) was dissolved in dichloromethane (337 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. Precipitation of insolubles was observed in the reaction tank along with the dropwise addition, and the precipitation of insolubles increased as the addition proceeded. After stirring was further continued for 4 hours, acetic acid (3.1 ml) was added and the mixture was stirred for 30 minutes. Thereafter, the stirring was stopped and both the organic layer and the insoluble matter were separated from the aqueous layer. The organic layer and the insolubles are washed with a 0.1 N aqueous sodium hydroxide solution (340 ml), then twice with 0.1 N hydrochloric acid (250 ml), and further washed with water (250 ml).
ml) twice.

The organic layer and the insoluble matter after washing were removed with methanol (2
(2) (3) in the above-mentioned general formula (1).
The target polyarylate resin F having the structural units (4) and (7) as shown in Table 1 was obtained. The obtained polyarylate resin F was insoluble in dichloromethane, and the viscosity average molecular weight could not be measured.

Production Example 7 (Production Method of Polyarylate Resin G of Comparative Example 2) Sodium hydroxide (8.48 g) and water (600 ml) were weighed into a 1 L beaker, and dissolved by stirring while bubbling with nitrogen. There, benzyltriethylammonium chloride (0.1040 g), bis- (4-hydroxyphenyl) methane (16.31 g), and p-
After adding t-butylphenol (0.3548 g) and stirring, the aqueous alkali solution was transferred to a 2 L reaction tank.

Separately, terephthalic acid chloride (11.8)
2g) and isophthalic acid chloride (5.07 g) were dissolved in dichloromethane (300 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. After further stirring for 4 hours, acetic acid (2.8 ml) and dichloromethane (1 ml) were added.
50 ml) and stirred for 30 minutes. Thereafter, the stirring was stopped and the organic layer was separated. This organic layer was washed with a 0.1N aqueous sodium hydroxide solution (280 ml), and then washed with 0.1N aqueous solution.
Washing was performed twice with 1N hydrochloric acid (810 ml) and further twice with water (810 ml). The washed organic layer was poured into methanol (1500 ml), and the resulting precipitate was taken out by filtration and dried, and the structural units of (2), (3), (4) and (7) in the general formula (1) were The target polyarylate resin G as shown in the following Table 1 was obtained. . The obtained polyarylate resin G was insoluble in dichloromethane, and the viscosity average molecular weight could not be measured.

Production Example 8 (Production Method of Polyarylate Resin H of Comparative Example 3) Sodium hydroxide (9.40 g) and water (673 ml) were weighed into a 1 L beaker, and dissolved by stirring while bubbling with nitrogen. There, benzyltriethylammonium chloride (0.1164 g), bis- (4-hydroxyphenyl) methane (17.89 g), and p-
After adding t-butylphenol (0.2684 g) and stirring, the aqueous alkali solution was transferred to a 1 L reaction tank.

Separately, terephthalic acid chloride (9.17)
g) and isophthalic acid chloride (9.17 g) were dissolved in dichloromethane (337 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. After stirring was further continued for 4 hours, acetic acid (3.1 ml) was added and the mixture was stirred for 30 minutes.
Thereafter, the stirring was stopped and the organic layer was separated. The organic layer was washed with a 0.1 N aqueous sodium hydroxide solution (340 ml), then twice with 0.1 N hydrochloric acid (250 ml), and twice with water (250 ml). .

The washed organic layer was washed with methanol (2250 m
The precipitate obtained by pouring into l) was taken out by filtration, dried, and the structural units of (2), (3), (4) and (7) in the general formula (1) were as shown in Table 1 below. The desired polyarylate resin H was obtained. The obtained polyarylate resin H was insoluble in dichloromethane, and the viscosity average molecular weight could not be measured.

Production Example 9 (Production method of polyarylate resin I of Comparative Example 4) bis- (4-hydroxyphenyl) methane (17.89)
g) was replaced with (2-hydroxyphenyl) (4-hydroxyphenyl) methane (17.89 g) in the same manner as in Production Example 8 except that (2) and (3) in the general formula (1) were used. The target polyarylate resin I having the structural units (4) and (7) as shown in Table 1 was obtained. The viscosity average molecular weight of the obtained polyarylate resin I was 16,400.

Production Example 10 (Production method of polyarylate resin J of comparative example 5) Sodium hydroxide (5.63 g) and water (404 ml) were weighed into a 1 L beaker, and stirred and dissolved while bubbling with nitrogen. There, benzyltriethylammonium chloride (0.0697 g), bis- (2-hydroxyphenyl) methane (10.72 g), and p-
After adding t-butylphenol (0.1908 g) and stirring, the aqueous alkali solution was transferred to a 1 L reaction tank.

Separately, terephthalic acid chloride (10.9
9 g) was dissolved in dichloromethane (202 ml) and transferred into a dropping funnel. While maintaining the external temperature of the polymerization tank at 20 ° C. and stirring the aqueous alkali solution in the reaction tank, a dichloromethane solution was dropped from the dropping funnel over 30 minutes. 4 more
After continuing stirring for an hour, acetic acid (1.9 ml) was added and the mixture was stirred for 30 minutes. Thereafter, the stirring was stopped and the organic layer was separated. This organic layer was washed with a 0.1N aqueous sodium hydroxide solution (200 m
1) washing, then 0.1N hydrochloric acid (150ml)
The washing was performed twice, and the washing was further performed twice with water (150 ml).

The organic layer after washing was washed with methanol (2000 m
The precipitate obtained by pouring the mixture into l) was taken out by filtration and dried, and the structural units of (2), (3), (4) and (7) in the above general formula (1) had the purposes shown in Table 1 below. Of polyarylate resin J was obtained.

[0089]

[Table 1]

<Production of Photoreceptor> Example 1 10 parts by weight of β-type oxytitanium phthalocyanine having the following structure was added to 4-methoxy-4-methylpentanone-
2 In addition to 150 parts by weight, pulverization and dispersion treatment was performed by a sand grind mill.

[0091]

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Also, 100 parts of a 5% 1,2-dimethoxyethane solution of polyvinyl butyral (Denka Butyral # 6000C, manufactured by Denki Kagaku Kogyo KK) and a phenoxy resin (PKH, manufactured by Union Carbide Co., Ltd.)
A binder solution was prepared by mixing 100 parts of a 5% 1,2-dimethoxyethane solution of H). To 160 parts by weight of the previously prepared pigment dispersion, 100 parts by weight of a binder solution,
An appropriate amount of 1,2-dimethoxyethane was added to finally prepare a dispersion having a solid content of 4.0%.

The thus obtained dispersion was applied on a polyethylene terephthalate film on which aluminum was vapor-deposited on the surface so as to have a thickness of 0.4 μm to provide a charge generation layer. Next, on this film, 50 parts by weight of the following hole transporting compound [1]

[0094]

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And 100 parts by weight of the polyarylate resin A produced in Production Example 1, an antioxidant (Irganox 10
76) 8 parts by weight and 0.03 part by weight of a silicone oil as a leveling agent are added to a 1,2-dichloroethane solvent 6
A solution dissolved in 40 parts by weight was applied, dried at 125 ° C. for 20 minutes, and a charge transport layer was provided so that the film thickness after drying was 20 μm. At this time, 1, 2 of the polyarylate resin A
-The solubility in dichloroethane solvent was good.
The coating solution did not show any change such as solidification even after being left at room temperature for one week. Table 2 shows the results of the solubility and solution stability.

Examples 2 to 5 and Comparative Examples 1 to 5 The same operation as in Example 1 was carried out using the polyarylate resin produced in each of the production examples. Table 2 shows the results of the solubility, the solution stability, and the state of the coated surface. The following evaluation was performed about each obtained photoreceptor.

[Electrical Properties] An electrophotographic property evaluation apparatus manufactured in accordance with the standards of the Electrophotographic Society of Japan (Basic and Application of Electrophotographic Technology, edited by the Society of Electrophotographic Engineers, Corona, 404-40)
5), the photoreceptor was attached to an aluminum drum to form a cylinder, and the aluminum drum and the aluminum base of the photoreceptor were electrically connected to each other. An electrical property evaluation test was performed by a cycle of charging, exposure, potential measurement, and static elimination. that time,
The initial surface potential is -700 V, monochromatic light of 780 nm for exposure and 660 nm for static elimination, and light of 780 nm is used for 2.
The surface potential (VL) at the time of irradiation of 4 μJ / cm ² was measured. In the VL measurement, the time required for the exposure-potential measurement was 139 ms. The measurement was performed at a temperature of 25 ° C. and a relative humidity of 50% (VL: NN). The smaller the absolute value of the surface potential (VL), the better the response. Table 2 shows the results.

[0098]

[Table 2]

From the above results, the polyarylate resin having a specific structure is excellent in electric characteristics, particularly responsiveness, and exhibits high solubility and solution stability in a coating solution solvent and a good coated surface state. It can be seen that by using this, an electrophotographic photoreceptor having good electric responsiveness can be stably obtained.

[0100]

The electrophotographic photoreceptor resin of the present invention has high solubility and solution stability in a coating solution solvent and excellent electrical characteristics, particularly responsiveness, by using a polyarylate resin having a specific structure. .

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 5/06 321 G03G 5/06 321 (72) Inventor Yuta Kumano 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsubishi Chemical Co., Ltd. (72) Inventor Akira Teru Fujii 1000, Kamosida-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsubishi Chemical Co., Ltd. F-term (reference) 2H068 AA13 AA20 BA02 BA11 BA13 BA16 BA21 BB27

Claims (8)

[Claims] Claims: 1. A photosensitive layer having at least a photosensitive layer on a conductive support.
Electrophotographic photoreceptor, the binder resin of the photosensitive layer is
Having a polyarylate structure represented by the general formula (1)
An electrophotographic photoreceptor, characterized in that: Embedded image In the general formula (1), X represents the following general formulas (2), (3) and
At least two types selected from the group represented by (4)
You. Embedded image Embedded image Embedded image R in the general formulas (2), (3) and (4)¹~ R^{twenty four}Is it
Each independently represents a hydrogen atom or an optionally substituted carbon
Chars which may have an alkyl group of 1 to 10 or a substituent
An alkoxy group having a prime number of 1 to 10, a halogen atom, a halogen
Alkyl group, C6 to C2 which may have a substituent
And 0 represents an aromatic group. Y¹~ Y^ThreeAre the same but different
May be a single bond, a divalent compound represented by the general formula (5)
Organic group of -O-, -S-, -CO-, -SO_Two-, Also
Or-(CH_Two)_s-(S is an integer of 1 to 5)
Represents any of Embedded image In the general formula (5), R^{twenty five}And R²⁹Are independent of each other.
An alkyl group having 1 to 10 carbon atoms which may have a substituent,
C1-C10 alkoxy optionally having a substituent
Group, halogen atom, halogenated alkyl group,
And represents an aromatic group having 6 to 20 carbon atoms which may be substituted. Also
R²⁶, R²⁷And R²⁸Are each independently a hydrogen atom,
An alkyl group having 1 to 10 carbon atoms which may have a substituent,
C1-C10 alkoxy optionally having a substituent
Group, halogen atom, halogenated alkyl group,
And represents an aromatic group having 6 to 20 carbon atoms which may be substituted. Also
R ^{twenty five}And R²⁶, R²⁷And R²⁸Are connected to each other to form a ring
May be. t is an integer of 0 or more, and u is an integer of 0 to 4
It is. Also represented by the following general formula (6) in the general formula (1)
Selected from the structures represented by the following general formula (7).
At least one. Embedded image Embedded image In the general formula (7), a and b are 1 ≧ a ≧ 0, 1 ≧ b ≧ 0
And a + b = 1. 2. In the general formula (7), a and b are 1 ≧ a /
2. The electrophotographic photosensitive member according to claim 1, wherein (a + b) ≧ 0.7. 3. R ^{1 in the} general formulas (2), (3) and (4)
The electrophotographic photosensitive member according to claim 1 or 2 to R ²⁴ is a hydrogen atom. 4. The electrophotographic photoreceptor according to claim ¹ , wherein Y ¹ , Y ² and Y ^{3 in the} general formulas (2), (3) and (4) are methylene groups. 5. The resin having a polyarylate structure represented by the general formula (1) having a viscosity average molecular weight of 15,000 to 1
The electrophotographic photoreceptor according to claim 1, wherein the ratio is 0.00000. 6. A photosensitive layer containing a charge transporting substance, wherein the charge transporting substance is a carbazole derivative, a hydrazone derivative, an aromatic or heterocyclic amine derivative, a stilbene derivative, a butadiene derivative, or a combination of a plurality of these derivatives. The electrophotographic photoreceptor according to claim 1, comprising at least one member selected from the group consisting of: 7. The electrophotographic photoreceptor according to claim 6, wherein the charge transporting substance comprises a plurality of aromatic or heterocyclic amine derivatives, stilbene derivatives, and butadiene derivatives. 8. The charge transporting material represented by the following general formula (8)
9. The method according to claim 6, wherein
Electrophotographic photoreceptor. Embedded image (In the general formula (8), Q represents a single bond or a divalent organic group.
And Ar¹~ Ar^FourEach independently has a substituent
Optionally having an arylene group or a substituent
A divalent heterocyclic group. m¹And m^TwoAre independent
Is 0 or 1 and m¹And m^TwoIs 0, Ar
^FiveAnd Ar⁶Each independently has a substituent
Good alkyl group, aryl optionally having substituent (s)
Group or a monovalent heterocyclic group which may have a substituent
And m¹And m^TwoIs 1, when Ar ^FiveAnd Ar⁶Haso
Alkylene optionally having a substituent
Group, arylene group which may have a substituent, or
A divalent heterocyclic group which may have a substituent;³⁰~
R³⁷Are each independently an optionally substituted al
Kill group, aryl group which may have a substituent, substituent
Optionally having an aralkyl group, a substituent
A monovalent heterocyclic group or a hydrogen atom, and n ¹~
n^FourAre each independently an integer from 0 to 4. Also A
r¹~ Ar⁶May combine with each other to form a cyclic structure
No. )