WO2000037529A1

WO2000037529A1 - Copolymer resin and binder resin comprising the same for electrophotographic photoreceptor

Info

Publication number: WO2000037529A1
Application number: PCT/JP1999/007102
Authority: WO
Inventors: Hirokatsu Sekiya; Toshihiro Yamamoto
Original assignee: Nippon Steel Chemical Co., Ltd.
Priority date: 1998-12-18
Filing date: 1999-12-17
Publication date: 2000-06-29

Abstract

A polyester carbonate copolymer resin having a number-average molecular weight (Mn) of 10,000 to 700,000 which is obtained by copolymerizing (D) 99.9 to 90 wt.% polyester carbonate with (E) 0.1 to 10 wt.% monomer having a double bond capable of undergoing copolymerization with the carbonate, wherein the ingredient (D) comprises (A) 5 to 70 wt.% aromatic polyester segment consisting of aromatic dicarboxylic acid units and aromatic diol units, (B) 10 to 75 wt.% polyester segment consisting of aromatic or aliphatic dicarboxylic acid units and aliphatic diol units, and (C) 20 to 85 wt.% aromatic polycarbonate segment, these segments being chemically bonded to one another, and the molecular chain of the ingredient (D) has a polymerizable double bond at an end. The resin is excellent in transparency, solvent solubility, and wearing resistance and is suitable for use as a binder resin for electrophotographic photoreceptors.

Description

Description Copolymer resin and binder resin for electrophotographic photosensitive member using the same

(Technical field) The present invention relates to a polyester carbonate copolymer resin excellent in abrasion resistance, a method for producing the same, a coating film using the same, a binder resin for an electrophotographic photosensitive member, and an electrophotographic photosensitive member. It is.

(Background Art) In recent years, resins for coating films having transparency and abrasion resistance have been used in various applications such as electric, electronic, and mechanical fields. In particular, attention has been focused on the use of organic photoreceptors as binder resins. Organic photoreceptors are known to have good processability and are advantageous in terms of manufacturing cost as electrophotographic photoreceptors, and have a high degree of freedom in functional design. This organic photoreceptor generally has a photosensitive layer formed on a conductive substrate. The photosensitive layer includes a charge generating material that generates a charge upon irradiation with light and a charge that transfers the generated charge. A single-layer type photosensitive layer containing a transfer material and a binder resin, a charge generation layer having a charge generation material and a binder resin, and a charge transfer layer having a charge transfer material and a binder resin. Laminated photosensitive layers with more separated functions are known.On the other hand, in the electrophotographic process, corona charging, development with toner, transfer, and cleaning steps are repeatedly performed. The photosensitive layer has excellent abrasion resistance to light, electrical and mechanical action, and abrasion resistance, as well as durability, and deteriorates in light-sensitive properties and charging properties when used repeatedly in various environments. It is necessary not to.

Copiers and printers using organic photoconductors instead of conventional inorganic photoconductors are increasing year by year. Organic photoreceptors are sensitive to a wide range of wavelengths from 400 to 800 nm, are more sensitive than inorganic photoreceptors, and are inexpensive to manufacture. i, a — Compared to Se-based photoreceptors, their mechanical durability is low and they are liable to wear, resulting in a decrease in sensitivity. It is not an exaggeration to say that the abrasion resistance and abrasion resistance are almost determined by the choice of the binder resin, but in practice they have limited abrasion resistance in practice. Therefore, there has been a strong demand for improved wear resistance. As a method for improving the abrasion resistance of the electrophotographic photoreceptor, various types of off-line and engineering plastic-based binder resins have been studied, and some of them have been tried by blending different resins. Other methods include a binder resin with abrasion-resistant silicone resin or fluororesin dispersed therein, a heat or photo-curable resin, and a protective layer on the outermost layer of the electrophotographic photoreceptor. Various studies have been made, such as having a charge transfer layer into two layers and using an abrasion-resistant resin for the outermost layer. However, conventionally known electrophotographic photoreceptors have not been sufficiently satisfactory, such as inferior electrical characteristics even if the abrasion resistance is improved.

In addition, various off-based and engineering plastic binder resins have been studied, and bisphenol A-type polycarbonate can exhibit good characteristics in terms of abrasion resistance, charging characteristics, sensitivity, residual potential, etc. Are known. However, the above bisphenol L-knol A-type polycarbonate has high polymer crystallinity, The solution has a drawback that it is liable to gel and becomes unusable at the level of 1 to 4. In addition, when a film is formed by coating, crystalline polycarbonate is deposited on the film surface during the formation of the coating film, and a projection is likely to be generated, toner adheres, and an image defect due to poor cleaning is easily generated. . Therefore, bisphenol Z-type polycarbonate with reduced crystallinity was studied, and the solution became less likely to cause gelation. However, bisphenol Z-type polycarbonate has poor hole transport properties due to poor compatibility and dispersibility with the hole transport agent. Furthermore, there is a drawback that the adhesiveness to a conductive substrate such as aluminum is poor, so that the adhesive peels off during repeated use.

For example, assuming that different resins are blended and used as a binder resin, Japanese Patent Application Laid-Open No. 5-34951 discloses bisphenol Z-type polycarbonate and ether imide or urethane or polyarylate. JP-A-6-273948 discloses blends of polycarbonate and polyester, and JP-A-6-289629 discloses blends of polycarbonate, polyester and polyarylate. In JP-A 1-282558, polycarbonate and polyester are blended, and in JP-A-57-4051, polycarbonate and polystyrene-acrylate are blended. JP-A-63-293548 discloses that a blend of polystyrene-acrylonitrile and poly (phenylene oxide) is used as a binder resin. It is disclosed for use. However, these blend-type binder resins have limited coating solvents, and the compatibility between the resins and the solvents is different.Therefore, phase separation occurs when left for a long time, and the stability of the coating solution is not sufficient. Could not say.

Also, JP-A-63-65449 discloses that a binder resin has abrasion resistance. The use of a dispersion of a silicon resin or a fluororesin is disclosed. However, silicon resin and fluororesin have poor compatibility with the charge transfer agent and the binder resin, causing the charge transfer layer to become opaque, resulting in uneven light transmittance in the opaque portion, and the background due to uneven sensitivity. There is a problem that dirt is generated.

Further, Japanese Patent Application Laid-Open No. 58-17448 discloses the use of a thermosetting resin such as urethane or epoxy as a binder resin. Japanese Patent Application Laid-Open No. 5-40358 discloses that epoxy is photocured and used as a binder resin. Japanese Patent Application Laid-Open No. 4-206651 discloses that an acrylic polymerizable monomer is photocured with a photoinitiator and used as a binder resin. However, there are problems such as deterioration of the reaction of the charge generating agent and the charge transfer agent during curing, and by-products such as unreacted functional groups and polymerization initiators remaining as impurities, leading to deterioration of electrical characteristics. ing. JP-A-1-129951, JP-A-2-158746, and JP-A-5-216249 disclose that a protective layer is provided on the outermost layer of an electrophotographic photosensitive member to improve abrasion resistance. I have. Japanese Patent Application Laid-Open No. 5-72751 discloses a method in which a charge transfer layer is divided into two layers and a resin having wear resistance is used for the outermost layer. However, the protective layer or charge transfer layer divided into two layers and provided with the outermost layer is considered to be due to instability of the charging property due to disturbance of the interface between the layers, accumulation of residual potential due to continuous repetition, and scratches. There is a problem that white streaks and black streaks easily occur.

Furthermore, the use of various modified polycarbonates is disclosed in JP-A-60-172044 and JP-A-5-345599, but is still not at a satisfactory level.

Therefore, the present inventors have disclosed in WO98 / Z1005, An ester carbonate copolymer resin was proposed. It was confirmed that this resin was excellent in terms of abrasion resistance and transparency, but it was found that higher abrasion resistance was required in some cases depending on the use form. For this reason, we tried to improve the abrasion resistance by increasing the molecular weight of the polyester carbonate resin, but the solution viscosity was too high and coating became difficult. occured.

2. Description of the Related Art Recoating of metal and other material surfaces with resin has been widely performed. As the method, there are a method in which the resin is melted by heat to coat the material, and a method in which the resin is dissolved in a solvent to form a solution, then applied to the material and dried. However, the method of melting the resin with heat and coating the material is limited to thermoplastic resin, and the decomposition of the resin due to heat, degradation of the resin, control of the film thickness of the resin, and the use of additives It is difficult to add. On the other hand, a method in which a resin is dissolved in a solvent to form a solution, then applied to a material and dried is a widely used method because it is easy to control the film thickness and to add additives. Transparent and abrasion-resistant coating film resins used in fields such as electric, electronic, and mechanical fields are highly utilizable, and various studies have been conducted.

It is an object of the present invention to provide a polyester carbonate copolymer resin having excellent transparency, excellent solvent solubility, reduced viscosity to facilitate handling, and particularly excellent abrasion resistance. The purpose of the present invention is to provide a coated film. Another object of the present invention is to provide a binder for an electrophotographic photoreceptor and a practically excellent electrophotographic photoreceptor that maintains excellent transparency and abrasion resistance for a long time. (Disclosure of the Invention) The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, obtained by copolymerizing polyester carbonate and a monomer copolymerizable therewith. Is excellent in transparency, solvent solubility, low viscosity and abrasion resistance, and is suitably used as a binder resin for an electrophotographic photoreceptor. The inventor found that the body was excellent in abrasion resistance, and based on this finding, completed the present invention.

That is, the present invention relates to an aromatic polyester part (A) composed of an aromatic dicarboxylic acid component and an aromatic diol component (A) 5 to 70% by weight, an aromatic dicarboxylic acid component or an aliphatic dicarboxylic acid component and an aliphatic diol. The polyester part (B) is composed of 10 to 75% by weight of the component and the aromatic polycarbonate part (C) is 20 to 85% by weight, and these parts are chemically bonded. And polyester having a polymerizable double bond at the terminal (D) 99.9 to 90% by weight, and a monomer (E) O.1 having a double bond copolymerizable therewith. A copolymer resin having a number average molecular weight (M n) of 100,000 to 700,000.

Further, the present invention provides a film having a thickness of 400% or more in a wavelength range of 400 to 800 nm when formed into a coating film having a thickness of 85% or more, and having a mouth opening form, methylene chloride and tetrahydrofuran at 25 ° C. The copolymer resin has a solubility in water of 10% by weight or more and a viscosity of 10% by weight or less at 25 ° C. in a form of a 10% by weight solution of black mouth at 200 ° C. Further, in the present invention, the light transmittance is 85% or more in a region of 400 to 800 nm when the light transmittance is a film thickness. This is a coating film formed from a synthetic resin and a coating film formed from a coating material obtained by blending a filler or other compounding agents with the coating film.

Furthermore, the present invention provides an aromatic polyester portion (A) composed of an aromatic dicarboxylic acid component and an aromatic diol component (A) in an amount of 5 to 70% by weight, an aromatic dicarboxylic acid component or an aliphatic dicarboxylic acid component and an aliphatic dicarboxylic acid component. It is composed of 10 to 75% by weight of a polyester part (B) composed of a diol component and 20 to 85% by weight of an aromatic polycarbonate part (C), and each of these parts has a chemical bond. Reacting an ester carbonate resin with an unsaturated compound having a functional group capable of reacting with a terminal functional group of the polyester carbonate resin, and polymerizing the terminal with a polyester carbonate having a double bond ( D), and then 99.9 to 90% by weight of a polyester carbonate (D) and a monomer (E) having a double bond copolymerizable therewith. % Copolymerized with Ru manufacturing method der copolymer resin characterized.

Furthermore, the present invention is an electrophotographic photosensitive member comprising the above-mentioned copolymer resin as a binder resin in a photosensitive layer. The photosensitive layer of the electrophotographic photosensitive member has a laminated structure of a charge generation layer and a charge transfer layer, and the charge transfer layer is preferably an electron-donating or electron-accepting layer. Are selected from phthalocyanines, azo dyes and perylenes as charge generators, and from triphenylamines, styryls, hydrazones and butadienes as charge transfer agents. It is advantageous to contain the selected drug and the above-mentioned copolymer resin as a binder resin. Further, the present invention is a binder resin for an electrophotographic photosensitive member comprising the above copolymer resin.

Hereinafter, the copolymer resin of the present invention will be described. The copolymer resin of the present invention basically comprises, at an end of a polyester carbonate resin portion composed of an aromatic polyester portion (A), a polyester portion (B), and a polycarbonate portion (C). It is a copolymer resin of a polyester carbonate (D) comprising a certain polymerizable double bond and a monomer (E) having a double bond copolymerizable therewith. Since this copolymer resin is obtained as a composition mainly containing a copolymer, the copolymer resin referred to in the present invention means a copolymer or a composition mainly containing a copolymer.

First, the aromatic polyester part (A) comprises a condensation polymerization part (ester bond) composed mainly of an aromatic dicarboxylic acid component and an aromatic diol component.

Aromatic dicarboxylic acid compounds (including acids, derivatives such as acid anhydrides and acid halides; the same applies hereinafter) which are the raw materials of the aromatic dicarboxylic acid component are exemplified by terephthalic acid, isophthalic acid, orthophthalic acid, and the like. Compounds such as 1,4-naphthalene dicarboxylic acid, 2,3-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, and diphenic acid are used, and these are used alone. Or two or more of them may be used in combination. Among them, a mixture of terephthalic acid and isophthalic acid from 25 Z 75 to 75/25 is preferable.

Examples of the aromatic diol compound as a raw material of the aromatic diol component include 2,2'-bis (4-hydroxyphenyl) propane (hereinafter abbreviated as bisphenol A), 4,4 '-(1-methyl- (Ethylidene) bis (2-methylphenol)

(Hereinafter abbreviated as bisphenol C), 4,4'-cyclohexylidenebisphenol (hereinafter abbreviated as bisphenol Z), 4,4'-ethylidenebisphenol, 4,4'-methylidenebis (2, 6-dimethylphenol), 4,4'- (1,3-dimethylbutylidene) bisphenol, 4,4 '-(1-methylethylidene) bis (2,6-dimethylphenol), 4,4'-(1-phenylethylidene) bisphenol, 5 , 5 '-(1-Methylethylidene) (Ι, Γ-biphenyl) -2-ol, (Ι, Γ-bi-phenyl) -4,4'-diol, 4,4'-methylenebisphenol, 4 , 4'-methylene bis (2-methylphenol), 4,4 '-(1-methyl-propylidene) bisphenol, 4,4'-(2-methyl-propylidene) bisphenol, 4,4 ( (Phenylmethylene) bisphenol, 4,4'-cyclohexylidenebis (3-methylphenol), 4,4 '-(9Η-fluorene-9-ylidene) bisphenol, 5,5'-cyclohexylidene ) Bis (Ι, Γ-biphenyl) -2-ol, 4,4'-oxybisphenol, bis (4-hydroxy-phenyl) methanone, 4,4'- (Diphenyl-methylene) bisphenol, 4,4'-propylidenebisphenol, 4,4 (1-ethylethylidene) bisphenol, 4,4 '-(3-methylbutylidene) bisphenol, 4,4 '-Cyclopentylidenebisphenol, 4,4'-cyclopentylidenebis (2-methylphenol), 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, 2 , 2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3-methyl-4-hydroxyphenyl) pulp bread, 2,2-bis (3-chloro- 4-Hydroxyphenyl) propane, 2,2-bis (3-bromo-4-hydroxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (4-hydroxyphenyl) Propane, 4,4 biphenol, 3, 3 ', 5, 5 tetramethyl-4,4 dihydroxybiphenyl, 4,4'-dihydroxy Aromatic diols such as benzophenone are exemplified. These may be used alone or in combination of two or more. In particular, bisphenol A, bisphenol C, and bisphenol Z are preferably used.

Next, the polyester part (B) contains an aromatic dicarboxylic acid component or a fatty acid. It comprises an aliphatic dicarboxylic acid component and a polycondensation unit (ester bond) composed mainly of an aliphatic diol component.

Examples of the aliphatic dicarboxylic acid compound serving as a raw material of the aliphatic dicarboxylic acid component include aliphatic dicarboxylic acids such as adipic acid, bimeric acid, sebacic acid, malonic acid, succinic acid, lingic acid, and citric acid. The compound of. Examples of the aromatic dicarboxylic acid compound as a raw material of the aromatic dicarboxylic acid component include terephthalic acid, isophthalic acid, orthophthalic acid, 1,4-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, Examples include compounds such as 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and diphenic acid. Of these, terephthalic acid is preferably used. In addition, these aromatic dicarboxylic acids or aliphatic dicarboxylic acids may be used alone, or two or more kinds may be used in combination, or an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid may be used in combination. Good.

Next, examples of the aliphatic diol compound which is a raw material of the aliphatic diol component include aliphatic glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, pentamethylene glycol, and hydrogenated bisphenol: L-Nol A. Diols and the like. These may be used alone or in combination of two or more. In particular, ethylene glycol and 1,4-butanediol are preferably used.

The polycarbonate part (C) is composed of a condensation polymerization part (carbonate bond) composed mainly of an aromatic diol component and a carbonic acid component.

Examples of the aromatic diol compound as a raw material of the aromatic diol component include bisphenol, bisphenol C, bisphenol Z, 4,4′-ethylidenebisphenol, and 4,4′-methylidenebisphenol. (2,6-dimethyl phenol), 4,4 '-(l, 3-dimethylbutylidene) bisphenol, 4,4'-(1-methylethylidene) bis (2,6-dimethylphenol), 4,4 '-(1-phenylenyl) Den) bisphenol, 5,5 '-(1-methylethylidene) (Ι, Γ-biphenyl) -2-ol, (Ι, Γ-biphenyl4 methylenebisphenol, 4,4 methylenebis ( 2-methylphenol), 4,4 '-(1-methyl-propylidene) bisphenol, 4,4'-(2-methyl-propylidene) bisphenol, 4,4 '-(phenylmethylene) bisphenol , 4,4'-cyclohexylidenebis (3-methylphenol), 4,4 '-(9'-fluorene-9-ylidene) bisphenol, 5,5'-(1,1'-cyclohexylidene) Bis (Ι, Γ-biphenyl) -2-ol, 4,4'-oxybisphenol, bis (4-hydroxy-phenyl) methanone, 4,4 (diphenyl -Methylene) bisphenol, 4,4'-propylidenebisphenol, 4,4 '-(1-ethylethylidene) bisphenol, 4,4'-(3-methylbutylidene) bisphenol, 4,4'-cyclopentylidenebisphenol, 4,4'-cyclopentylidenebis (2-methylphenol), 2,2-bis (3,5-dichloro-4-hydroxycyclophenyl) propane, 2,2- Bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (2-chloro-4-4-hydroxyphenyl) propane , 2,2-bis (3-bromo-4-hydroxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (4-hydroxyphenyl) propane, 4,4 ' -Biphenol, 3,3 ', 5,5 tetramethyl-4,4'-dihydroxybiphenyl, 4,4'-dihydroxybenzophen .. Aromatic diols such emissions and the like may be these used alone or in combination of two or more particular, bisphenol A, Bisufueno Le C, Bisufu:! : Nol Z is preferably used.

Polyester composed of the above structural units (A), (B) and (C) During Terukabone preparative resin portion, the structural unit (A) is 5-7 0% by weight, rather better good 2 0-5 0 weight ⁰ / o, (B) is 1 0-7 5% by weight, preferably 2 0 to 50% by weight, and (C) 20 to 85% by weight, preferably 30 to 60% by weight. Each structural unit can be present at any position, but is preferably present as one or two or more blocks. The polyester carbonate resin (which provides this polyester carbonate resin part) PEC) can be obtained by a known method. Preferably, it is a method in which an aromatic polyester resin (also referred to as polyarylate), a polyester resin, and a polycarbonate resin are melt-kneaded at a predetermined mixing ratio. That is, by melt-kneading these resins, a transesterification reaction is induced between the ester bond of the aromatic polyester resin and the polyester resin and the carbonate bond of the polycarbonate resin, and the polyester carbonate resin is melted. (PEC) is formed.

Examples of the melt-kneading method include a reaction vessel equipped with a stirring blade, a general extruder, an injection molding machine, a Brabender, a kneader, and a Banbury mixer. The melt-kneading temperature is not lower than the glass transition temperature of these resins, and is preferably 50 ° C. or higher than the glass transition temperature in order to sufficiently plasticize these resins.

At this time, a known ester polymerization catalyst may be added in order to promote the transesterification reaction between the aromatic polyester resin, the polyester resin, and the polycarbonate resin. Specific examples of the ester polymerization catalyst include metal acetates, alkoxides, and hydroxides such as Na, Mg, Zn, Cd, Ti, Pb, Sb, and Sn. . Specifically, zinc acetate, magnesium acetate, antimony acetate, germanium acetate, lead monoxide, lead dioxide, tet Examples include lamethyl titanate and tetraethyl titanate. This addition method is not particularly limited. The amount of the sulfur exchange catalyst to be added is 3% by weight or less, preferably 0.5% by weight or less, based on the total amount of the resin. If it exceeds 3% by weight, the color tone of the copolymer resin may be deteriorated. When the above catalyst is used, a known catalyst deactivator can be added to prevent a side reaction after the reaction. These deactivators only need to be compounds that can suppress the function of decomposing the ester bond or the carbonate bond, and specifically, a phosphorus compound is preferable. Examples of the phosphorus compound include orthophosphoric acid, phosphonic acid, and phosphite, among which phosphite is most preferably used. Specific examples of phosphites include alkyl phosphites, aryl phosphites, alkyl aryl phosphites, diphosphites, polyphosphites, and thiophosphites. These include diisooctyl phosphite, distearyl phosphite, triisodecyl phosphite, triisooctyl phosphite, trilauryl phosphite, tristeoleile phosphite, diphenyl phosphite, and triphenyl phosphite. Examples thereof include phenyl phosphite and phenyldiisodesyl phosphite. The method of adding the catalyst deactivator is not particularly limited, but is preferably after the above-mentioned catalyst is sufficiently reacted with the aromatic polyester resin, the polyester resin, and the polycarbonate resin in the first step. As a second step, it is preferable to add a quencher to inactivate the catalyst. In addition, a known resin additive such as a heat stabilizer, an antioxidant, and a release agent can be added at the time of melt-kneading as long as the progress of the transesterification reaction is not impaired.

Polyester carbonate with polymerizable double bond at the end (D) preferably has an average of one or two, preferably one or two double bonds per molecule at the terminal of the polyester carbonate resin part. A small amount of polyester carbonate having no double bond may be left. In the case of a linear shape, the number of terminal double bonds is two at the maximum.

As the polyester carbonate (D), a compound having a double bond polymerizable via a functional group capable of reacting with a terminal functional group of the polyester carbonate resin (PEC) obtained by the above method is introduced. This is the simplest method, but is not limited to this.

For example, if at least one terminal of the polyester carbonate resin (PEC) is an OH group, a vinyl compound capable of reacting with the polyester carbonate resin (PEC) and the HH group, such as methacrylic acid, When an acid having a double bond such as acrylic acid or an acid anhydride thereof, or a derivative such as acid chloride is reacted by a known esterification method, polyester carbonate having a double bond can be obtained. D) can be obtained.

If at least one terminal of the polyester carbonate resin (PEC) is a COH group, a method such as introduction of a derivative such as vinylamine by a known amidation method is also possible. Then, it is possible to introduce double bonds at both ends by aligning the ends of the polyester carbonate resin (PEC) to either OH groups or COOH groups or, if not, performing the reaction in two steps. However, introduction at one end is sufficient.

The copolymer resin of the present invention can be obtained by copolymerizing the polyester carbonate (D) having a polymerizable double bond and a monomer (E) copolymerizable therewith. Polyester carbonate (D) and single quantity The proportion of body (E), (D) is 99.9-90 weight ⁰ /. With respect to, (E) force "0."! ~ 1 0 weight ^_0/0, is favored properly is from 2 to 8% by weight 0.1.

The copolymerization method may be a radical polymerization method using a solvent in which polyester carbonate (D) is dissolved under the condition of adding or not adding a known radical polymerization initiator, or in the presence of a known ionic polymerization initiator. Copolymerization can be carried out by a known method such as a method by ionic polymerization performed in the above.

Examples of the monomer (E) used for copolymerization include styrene, para-methylstyrene, styrene derivatives such as P-methylstyrene, and methacrylic acid and methyl methacrylate. Acrylates such as methacrylate, acrylate, methyl acrylate, and butyl acrylate, and copolymerizable double bonds such as vinyl acetate, acrylonitrile, and butadiene. Having a monomer. These may be used alone or in combination of two or more. The reactivity of the double bond of each of the monomer (E) and the polyester carbonate (D) is preferably copolymerized at random so that there is no large difference.

The copolymer resin of the present invention thus obtained is obtained by copolymerizing with the monomer (E) having a double bond capable of copolymerizing with the polyester resin (D). It has a structure in which the double bond of carbonate (D) and the double bond of monomer (E) are bonded. Although there is no particular limitation on the bonding structure, it is preferable that one or more polyester carbonates (D) are bonded to the polymer part (E n). That is, if the structural units of the copolymer are represented by D and E, respectively, it is preferable that the copolymer has, for example, a structure represented by the following formula (1).

E n — (D m — E n) q — D m (1) Here, n, m, and q each independently represent 0 or an integer of 1 or more, but nm and q do not all become 0. Both ends can be D or E. Also, D is preferably in the range of a number average molecular weight (Mn) force of 1, 000 to 100,000, preferably 5, 000 to 500, 0000. D has a long chain shape, and shows a structure in which a polyester carbonate resin part constituting D is graphed on a chain composed of a double bond of E and D.

The copolymer resin of the present invention has a number average molecular weight (M n) of 100, 000 to 700, preferably 200, 000 to 700, 000, More preferably, it is 100.000 to 600,000. The number average molecular weight (Mn) of the copolymer resin greatly affects the mechanical strength and abrasion resistance of the molded product.If the number average molecular weight is less than 100,000, the mechanical strength and abrasion resistance are significantly reduced. However, when the viscosity exceeds 700,000, the solution viscosity increases remarkably, and the coating work becomes difficult. The number average molecular weight (Mn) of the polyester carbonate (D) is preferably about 1Z2 to 130 of that of the copolymer resin.

When the content of the aromatic polyester resin part (A) in the polyester carbonate constituting the copolymer resin of the present invention is less than 5% by weight, the crystallinity of the copolymer resin is increased and the transparency of the coating film is impaired. If it exceeds 0% by weight, the effect of improving wear resistance is reduced. If the amount of the polyester resin portion (B) is less than 10% by weight, the effect of improving abrasion resistance is reduced. If the content of the polycarbonate resin part (C) is less than 20% by weight, the coloration derived from the ester bond of the copolymer resin may be increased, and the application is limited. The effect of improving wear resistance is reduced. The polymer (E n) generated from the monomer (E) has 1 If it exceeds 0% by weight, the effect of abrasion resistance decreases and the viscosity also increases. In this case, the homopolymer of the monomer (E) is generated, or the chain length is increased, so that the compatibility is reduced and the transparency is reduced. On the other hand, if it is less than 0.1% by weight, the wear resistance is reduced.

Various resin additives can be mixed with the copolymer resin of the present invention as required and as needed. These resin additives include, for example, heat stabilizers, antioxidants, light stabilizers, release agents, lubricants, pigments, flame retardants, plasticizers, antistatic agents, antibacterial and antifungal agents, charge generation Agents, charge transfer agents and the like. In addition, for example, fiber reinforcing agents such as glass fiber, metal fiber, titanic acid whisker, and carbon fiber, talc, calcium carbonate, my strength, glass flakes, milled fiber, metal flakes, and metal powder fillers A system enhancer may be mixed.

Next, the coating film of the present invention will be described.

The copolymer resin of the present invention can be used as a coating film on the surface of materials including metals. Examples of the application of this coating film include various applications such as known electric, electronic, and mechanical fields. As the coating method, there is a method in which the copolymer resin is melted by heat to coat the material, or a method in which the copolymer resin is dissolved in a solvent to form a solution, and then applied to the material and dried. Yes, either method is acceptable. Coating can be performed using various well-known coating devices. Specifically, an applicator, a spray coater, a nozzle coater, a chip coater, a mouth coater, a zipper coater, and the like. First, a doctor blade can be used.

When this coating film is 25 m thick, the minimum light transmittance in the range of 400 to 800 nm is 85 <½ or more. The coating film of the present invention includes those formed from a paint containing a filler such as a pigment or other compounding agents. In this case, the copolymer resin (which may be dissolved in a solvent) used for the resin must have the above light transmittance.

The copolymer resin of the present invention can be used as a binder resin in single-layer and multi-layer photoconductors. By using this resin, it is excellent in abrasion resistance and optical properties. Thus, an electrophotographic photoreceptor excellent in image quality can be obtained and can be suitably used in various electrophotographic fields.

The copolymer resin used as the binder resin for an electrophotographic photoreceptor of the present invention (may be abbreviated as a binder resin) is basically composed of an aromatic polyester part (A) and a polyester part (B). And a polycarbonate part (C), which is chemically bonded to each other and has a copolymerizable double bond, and a copolymerizable polyester resin (D). A copolymer or a resin composition obtained by copolymerizing a monomer (E) having a double bond with

The copolymer resin used as the binder resin for an electrophotographic photoreceptor of the present invention may be composed of only the copolymer represented by the above formula (1), but depending on the copolymerization conditions, polyester carbonate may be used. It may be a resin composition containing a resin and a homopolymer of the monomer (E).

First, the copolymer resin used as the binder resin for an electrophotographic photosensitive member used in the present invention preferably has a light transmittance of 85 ° / o or more. In the present invention, the light transmittance refers to the transmittance when a coating film having a thickness of 25 m is measured in a wavelength range of 400 to 800 rim. If the light transmittance is less than 85%, application to optical applications becomes difficult. To improve light transmittance, copolymerization The ratio of the component derived from the monomer (E) in the resin is related, and if this ratio is large, the transmittance decreases.

The solubility of the copolymer resin used as the binder resin for an electrophotographic photoreceptor of the present invention is preferably 10% by weight or less. In the present invention, the solubility refers to the amount of the copolymer resin dissolved in any of form-form, methylene chloride and tetrahydrofuran at 25 ° C. In resin coating applications, the higher the solubility of the resin in the solvent, the easier it is to control the film thickness. Usually, a methylene chloride or a chlorinated solvent such as clog form is used as a coating solvent for the polyarylate and the polycarbonate. Therefore, it is preferable that the copolymer resin of the present invention is also dissolved in these solvents. In addition, with the recent shift to dehalogenated solvents, solubility in tetrahydrofuran and the like is also required. To improve the solvent solubility, it is not as strict as improving the light transmittance, but the polyester part with poor solvent solubility is introduced into the composition so as to form a copolymer, and the insoluble part does not exist It is important.

Furthermore, in the copolymer resin used as the binder resin of the present invention, it is necessary that the viscosity at the time of dissolving 10% by weight of a 25 ° C. clog mouth form is 20 Ocp or less. If the viscosity exceeds 200 cp, the workability during coating decreases. The binder resin of the present invention can be mixed with various resin additives as needed to form a binder. These resin additives include heat stabilizers, antioxidants, light stabilizers, release agents, lubricants, pigments, flame retardants, plasticizers, antistatic agents, antibacterial antifungal agents, charge generators, and electric charges. Transfer agents and the like. Also, fiber reinforcement such as glass fiber, metal fiber, titanic acid whisker, carbon fiber, talc, calcium carbonate, my strength, glass flake, mill Filament-based reinforcing agents such as fiber, metal flake, metal powder, etc. may be mixed.

Next, a method for forming a coating film of the binder resin used in the present invention will be described.

The method of applying the binder resin of the present invention includes a method of melting the resin by heat and coating the material, and a method of dissolving the resin in a solvent to form a solution, and then applying and drying the material. There is a method to do either of them. The coating can be performed using various known coating apparatuses. Specifically, an applicator, a spray coater, a bar coater, a chip coater, a mouth coater, a dip coater, a doctor blade, and the like can be used. Power to use This coating film has a minimum light transmittance of 85% or more in a region of 400 to 800 nm at a thickness of 25 im.

Hereinafter, the electrophotographic photoreceptor of the present invention will be described.

The binder resin for an electrophotographic photoreceptor of the present invention can be applied to various known types of electrophotographic photoreceptors as long as it is used as a binder resin in a single-layer type or a laminated type photoreceptor. . Preferably, it is preferably used as a binder resin of a charge transfer layer in a laminated electrophotographic photosensitive member having a photosensitive layer having at least one charge generation layer and at least one charge transfer layer.

In the electrophotographic photoreceptor of the present invention, at least the copolymer resin of the present invention may be contained in the photosensitive layer as a binder resin, and may be used in combination with another binder resin. In this case, the other binder resin can be used in an appropriate amount as long as the wear resistance and the transparency, which are the objects of the present invention, are not impaired.

Examples of such other binder resins include styrene-based polymers, styrene-butadiene copolymers, styrene-acrylonitrile copolymers, Styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyester, polyamide, Polyurethane, polycarbonate, polyarylate, epoxy resin, polysulfone, diaryl phthalate resin, silicon resin, ketone resin, polyvinyl butyral resin, polyether resin, phenolic resin, and epoxy resin And photocurable resins such as urethane acrylate. In addition, a photoconductive polymer such as poly-N-vinyl carbazole, which can be used as a charge transfer agent, can also be used as a binder resin, and additives such as an antioxidant may be added as necessary. You may.

As the conductive substrate material used for the electrophotographic photoreceptor of the present invention, various conventionally known materials can be used, for example, aluminum, brass, copper, nickel or steel. Conductive materials such as aluminum, nickel, chromium, palladium, and graphite are coated on a metal plate, drum or metal sheet plastic sheet by vapor deposition, sputtering, coating, etc. Use a material that has been subjected to a passivation treatment, a metal drum surface that has been subjected to a metal oxide treatment by electrode oxidation, etc., or a substrate that has been subjected to a conductivity treatment such as glass, plastic plate, cloth, or paper. be able to.

The charge generation layer of the multi-layer type electrophotographic photoreceptor has at least a charge generation substance, and the charge generation layer is formed on a substrate as an underlayer by vacuum deposition, sputtering, or the like. Can be formed, or a layer can be formed by binding a charge generating substance on a base substrate using a binder resin. binder As a method for forming the charge generation layer using a resin, various methods such as a known method can be used, but usually, for example, the charge generation substance is dispersed or dissolved in an appropriate solvent together with a binder resin. A method in which the applied coating liquid is applied onto a substrate serving as a predetermined base and dried is suitable.

As the charge generating substance, various substances such as known substances can be used. For example, amorphous selenium, selenium alone such as trigonal selenium, selenium alloys such as selenium-tellurium, and selenium such as AsSe: Compounds or selenium-containing compositions, zinc oxide, inorganic materials consisting of Group II and IV elements such as CdS-Se, oxide semiconductors such as titanium oxide, and silicon such as amorphous silicon Inorganic materials such as metal-based materials, metal or metal-free phthalocyanine, cyanine, anthracene, bisazo compounds, pyrene, perylene, pyrylium salt, thiapyridium salt, polyvinyl carbazole, and square: Earium pigment. Examples include organic materials. These may be used alone or in combination of two or more.

The binder resin in the charge generation layer is not particularly limited, and various kinds of known resins can be used. For example, a styrene-based polymer, a styrene-butadiene copolymer, and a styrene-acrylonitrile copolymer may be used. Copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, poly Esters, polyamides, polyurethanes, polycarbonates, polyarylates, epoxy resins, polysulfones, diaryl phthalate resins, silicone resins, ketone resins, polyvinyl butyral resins, polyether resins, phenolic resins, , Epoxy acrylate, urethane acrylate etc. To use Can be. As the binder resin in the charge generation layer, it is preferable to use the copolymer resin of the present invention.

The mixing ratio (weight ratio) of the charge generating substance and the binder resin is preferably from 20: 1 to 1:20. The thickness of the charge generation layer is generally set in the range of 0.01 to 5 im, preferably in the range of 0.05 to 2.0 om.

Next, the charge transfer layer can be obtained by forming a layer in which a charge transfer substance is bound to a binder resin on a base substrate. The method for forming the charge transfer layer using a binder resin may be a known method. Usually, for example, a coating solution in which a charge transfer material is dispersed or dissolved in a suitable solvent together with a binder resin is applied to a predetermined substrate. The method is preferably applied on a substrate to be formed and dried.

The binder resin of the present invention is used for the charge transfer layer. In this case, the binder resin may be used alone or two or more kinds may be used in combination. Further, other binder resins can be used in combination with the copolymer resin of the present invention as long as the purpose of the present invention is not impaired, but it is preferable that the content be 50 wt% or less of the binder resin.

Examples of the charge transfer material used in the electrophotographic photoreceptor of the present invention include a conventionally used electron transfer material and hole transfer material. Specific examples of the electron-transporting substance include, for example, chloranil, bromanyl, 2,2-dichloro-5,6-dicyanobenzoquinone, tetrathanoethylene, tetrathanoquinodimethane, and 2,4,7- Trinitro-9-fluorenone, 2,4,5,7-Tetranitro-9-fluorenone, 2,4,7-Trinitro-9-dicyanomethylenefluorenone, 2,4,5,7 -Dipheno, such as -tetranitroxanthone, 2,4,9-trinitrothioxanthone, or 3,5-dimethyl-3 ', 5'-di-t-butyl-4,4'-diphenoquinone Examples thereof include electron-withdrawing substances such as quinone derivatives, and those obtained by increasing the molecular weight of these electron-withdrawing substances. These may be used alone or in combination of two or more.

Examples of the hole-transporting substances include pyrene, N-ethylcarbazole, N-isopropylpyrcarbazole, N-methyl-N-phenylhydrazino-3-methylidene-9-ethylcarbazol, and Ν, Ν-diphenylhydrazino. -3-methylidene-9-ethylcarbazol, Ν, Ν-diphenylhydrazino-3-methylidene-10-ethylethylphenothiazine, Ν, Ν-diphenylhydrazino, -3-methylidene-10-ethylethylenoxazine, Ρ-methylaminobenzaldehyde Ν, Ν-Diphenylhydrazone, Ρ-Jetylaminobenzaldehyde-Ν-hi-naphthyl-Ν-phenylhydrazone, Ρ-pyrrolidino benzaldehyde -Ν, Ν-diphenylhydrazone, 1,3,3-trimethylylazoneド-レ--Ν-Ν-Ν-Ν-diphenylhydrazone, -getylpenzaldehyde-3-methylbenzthiazolinone -2 -Hydrazone, 1-phenyl-1,2,3,4-tetrahydroquinoline-6-carboxyaldehyde -Γ, Γ-Diphenylhydrazone and other hydrazones, 2,5-bis (Ρ-ethylpyraminophenyl) -1,3,4-oxadiazole, 1-phenyl-3- (ρ-methylethylstyryl) -5- (ρ-ethylethylaminophenyl) pyrazolin, 1- [quinolyl (2)]-3- (ρ- Jetylamino styryl) -5- (ρ-Jetylaminophenyl) pyrazolin, 1- [Levidil (2)]-3- (ρ-ethylaminostyryl) -5- (Ρ-Jetylaminophenyl) pyrazolin, 1- [6-Methoxy-pyridyl (2)]-3- (ρ-Gethylaminostyryl) -5- (ρ-Getylaminophenyl) virazoline, 1- [Pyridyl ( ⁵ )]-3- (ρ-Getylaminophenyl) ) pyrazol down, 1- [pin lysyl (2)] - ³ _ (ρ- Jefferies chill § Minos Chile Lumpur) - ⁵ - (ρ- Jechi Amino phenyl) pyrazol down, [pyridyl (2)] -3- (ρ- Jechiruami Nosuchiriru) -4-methyl-5 (p-Jethylaminophenyl) pyrazolin, 1- [pyridyl (2)]-3- (hi-methyl-P-getylaminostyryl) -5- (p-Jethylaminophenyl) pyrazolin, 1-phenyl -3- (p-Jetylaminostyryl) -4-methyl-5- (p-Jetylaminophenyl) pyrazoline, 1-phenyl-3-((h-benzyl-Jetylaminostyryl) -5- (p- Pyrazolines, such as pyrazoline and spirovirazolin, 2- (p-getylaminostyryl)-(5-getylamino benzoxazole, 2- (p- getylaminophenyl) -4- (p- Oxazole compounds such as (ethylaminophenyl) -5- (2-chlorophyl) oxazole, thiazole compounds such as 2- (p-ethylaminobutyryl) -6-ethylethylaminobenzothiazole, and bis (4-getylamino-2-) Met Triarylmethane compounds such as phenyl) phenylmethane, 1,1-bis (4-Ν, Ν-ethylpyramino-2-methylphenyl) heptane, 1,1,2,2-tetrax (4-Ν, Polyarylamines such as Ν-Jethylamino-2-methylphenyl) ethane, Ν, Ν'-diphenyl -Ν, Ν'-bis- (methylphenyl) benzidine, Ν, Ν'-diphenyl -Ν, Ν ' -Bis- (ethylphenyl) benzidine, Ν, Ν'-diphenyl-ジ, Ν bis- (propylphenyl) benzidine, Ν, Ν'-diphenyl-Ν, Ν'-bis- (butylphenyl) benzidine, Ν , Ν'-Diphenyl -Ν, Ν'-bis- (isopropylpyrphenyl) benzidine, Ν, Ν'-diphenyl -Ν, Ν'-bis- (t-butylphenyl) benzidine, Ν, Ν-diphenyl- Ν, Ν'-Bis- (cloth phenyl) Benzidine compounds such as benzidine, and phenyl stilbene Styryl compound or butadiene compound, triphenylamine, poly-Ν-vinylcarbazole, polyvinylvinylene, polyvinylanthracene, polyvinylacrylic acid, poly-9-vinylphenylanthracene, organic polysilane, pyrene- Formaldehyde resin, ethyl carbazole-ho Lumaldehyde resin and the like. These may be used alone or in combination of two or more.

The mixing ratio (weight ratio) of the charge transfer material to the binder resin is preferably from 10: 1 to 1: 5. The thickness of the charge transfer layer is generally set in the range of 5 to 50 m, and preferably in the range of "I 0 to 30 im.

Solvents used for forming the charge generation layer and the charge transfer layer include, for example, aromatic solvents such as benzene, toluene, xylene, and chlorobenzene, acetone, methylethylketone, and cyclohexanone. Ketones, alcohols such as methanol, ethanol, isopropanol, etc., esters such as ethyl acetate, ethyl sorbate, carbon tetrachloride, chloroform, dichloromethane, tetrachloroethane, 1,2- Examples thereof include halogenated hydrocarbons such as dichloroethane, ethers such as tetrahydrofuran and dioxane, dimethylformamide, dimethylsulfoxide, and getylformamide. These solvents may be used alone or in combination of two or more.

The coating of each layer can be performed using various types of coating equipment such as a known one.For example, using an applicator, a spray coater, a bar coater, a chip coater, a roll coater, a dip coater, a doctor blade, etc. Can be.

The photosensitive layer of the single-layer type electrophotographic photosensitive member contains the copolymer resin of the present invention as a binder resin, at least the charge generating substance and the charge transfer substance, and forms the photosensitive layer. As the method, various methods such as a known method can be used. For example, a coating liquid in which a charge generation material and a charge transfer material are dispersed or dissolved in a suitable solvent together with a binder resin, A method in which the composition is applied onto a substrate serving as a predetermined base and dried, and the like can be suitably used. Further, other binder resins can be used in combination with the copolymer resin of the present invention as long as the object of the present invention is not impaired.

The electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor having excellent abrasion resistance and optically excellent by using the copolymer resin of the present invention as a binder resin. It can be suitably used in the photographic field.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

The aromatic polyester resin, polyester resin and polycarbonate resin used as the raw material resin are as follows.

Aromatic polyester resin: Bisph: Phenol A tere and isophthalic acid type aromatic polyester resin (U-"! 00" manufactured by Unitika Ltd.)

Polyester resin: Polybutylene terephthalate resin (Hardic A54010 manufactured by Asahi Kasei Corporation)

Polycarbonate resin: Bisfu I-noll A-type polycarbonate resin (NOVAREX 720A manufactured by Mitsubishi Chemical Corporation)

The molecular weight of the copolymer resin is measured by gel permeation chromatography using a tetrahydrofuran solvent (GPC: manufactured by Tosoh Corporation), and is expressed in terms of molecular weight in terms of polystyrene.

Production Examples 1 to 8

(Manufacture of polyester carbonate resin)

Aromatic polyester resin (resin A) and polyester resin (resin B) The polycarbonate resin (resin C) was melt-kneaded by a screw-type twin-screw extruder without a catalyst (conditions: 290 ° (:, screw rotation speed: 100 rpm)). The polyester carbonate resin is produced by sampling a kneaded sample to create a 5 m thick cast film (solvent: black-mouthed form) and using a phase-contrast microscope (Alice Plan manufactured by Leica Co., Ltd.). This was confirmed by analyzing the phase state (change to a one-phase state when the copolymer was formed.) Ratio of resin A, B, and C in the obtained polyester carbonate resin, polyester carbonate The molecular weight and light transmittance of the resin are shown in Table 1. In Production Examples 5 and 8, the molecular weight and transmittance could not be measured because the generated resin was insoluble in the solvent, and in Production Example 6, the film strength was insufficient. Measurement of transmittance It did not come.

Example 1

(Synthesis of copolymer resin)

To introduce a double bond into the polyester carbonate resin of Production Example 1, 50 g of the resin was dissolved in 500 ml of methylene chloride, and then 15.18 g of triethylamine was used as a basic catalyst. Was added thereto, and while stirring, 2.63 g of methacrylic acid mouth light was added dropwise to react. After the resulting reaction solution was post-treated, it was dropped into methanol, and the precipitated resin was filtered and dried under reduced pressure to obtain 48 g of a resin. 'H-NMR confirmed the introduction of double bonds in the obtained resin. Next, after dissolving 5 g of the double bond-introduced polyester carbonate resin and 16 mg (0.32 weight ⁰ / o) of styrene in 1,4-dioxane, benzoyl peroxide was added. As an initiator, the temperature was raised to 100 ° C., and the mixture was reacted with stirring. The reaction solution was added dropwise to methanol, and the precipitate was filtered and dried under reduced pressure to obtain 4.75 g of a copolymer resin. GPC of this copolymer resin The number average molecular weight (Mn) was 260,000.

(Solution viscosity measurement)

10 g of the above copolymer resin was dissolved in black mouth form to prepare a 10% by weight black mouth form coating solution. This coating solution was maintained at 25 ° C., and the solution viscosity was measured by a vibrating viscometer to be 197 cp.

(Abrasion resistance test)

The above coating solution is applied to an aluminum substrate (1 Ocmx10 cm) using a bar coater, dried in an oven at 120 ° C for 60 minutes, and then coated to a thickness of 30 μm. A film was formed. The coating film was subjected to a wear resistance test using a Taber abrasion tester under the conditions of a wear wheel CS-17, a load of 500 g x 2, 1,000 rotations, and 60 rpm. The amount of wear was 7.8 mg.

(Measurement of transmittance)

The above coating liquid was applied to a glass substrate using a bar coater, and dried in an oven at 120 ° C. for 60 minutes to form a coating film having a thickness of 25 m. This coating film was measured for light transmittance in the measurement wavelength range of 400 to 800 nm using a spectrum photometer (U-400, manufactured by Hitachi, Ltd.). The minimum transmittance was 89%.

Examples 2 to 5

0.4 8 weight the amount of styrene ⁰ / o, 0. 6 4 wt%, 1.2 8 wt ⁰ / o, 6. was changed to 5 wt%, in the same manner as in Example 1 copolymer resin Were synthesized and evaluated. Table 2 shows the results.

Examples 6 to 10

The monomer was changed to butyl acrylate, and the added amount was 0.32% by weight, 0.48% by weight, 0.64% by weight, 1.28% by weight, and 6.5% by weight. Less than Except for the above, a copolymer resin was synthesized and evaluated in the same manner as in Example 1. Table 2 shows the results.

Examples 11 to 15

The monomer was changed to methacrylic acid, and the added amounts were 0.32% by weight, 0.48% by weight, 0.64% by weight, 1.28% by weight, and 6.5% by weight. Except for the above, a copolymer resin was synthesized and evaluated in the same manner as in Example 1. Table 2 shows the results.

Example 16 to 20

The monomer was changed to methyl methacrylate, and the added amount was 0.32% by weight, 0.48% by weight, 0.64% by weight, 1.28% by weight, 6.5% by weight. Except for this, a copolymer resin was synthesized and evaluated in the same manner as in Example 1. Table 2 shows the results.

Example 21 to 25

Change the monomer accession Li Loni tolyl, an amount 0.3 2% by weight, 0.4 8% by weight, 0.6 4 wt ⁰ / o, 1. 2 8 wt ⁰ / o, 6. 5 A copolymer resin was synthesized and evaluated in the same manner as in Example 1 except that the weight% was used. Table 2 shows the results.

Comparative Examples 1 to 10

A copolymer resin was synthesized and evaluated in the same manner as in Example 1 except that the type and amount of the monomer were changed as shown in Table 3. Table 3 shows the results. Comparative Example 1 1

A copolymer resin was synthesized and evaluated in the same manner as in Example 1 except that the copolymer resin was changed to bisphenol Z-type polycarbonate (Iupilon Z-300, manufactured by Mitsubishi Gas Chemical Company). Table 3 shows the results. From the comparison between Examples 1 to 25 and Comparative Examples 1 to 11, it is confirmed that the copolymer resin of the present invention has low viscosity, excellent transparency, and particularly excellent wear resistance. .

【table 1 】

Production example Resin ratio (% by weight) Molecular weight Transmittance Resin A Resin B Resin C

1 20 30 50 22,000 86

2 10 15 75 19,000 82

3 30 45 25 19,000 80

4 55 20 25 20,000 83

5 0 30 70 Solvent insoluble Solvent insoluble

6 50 0 50 18,000 Film crack

7 80 10 10 19,000 62

8 10 80 10 Solvent insoluble Solvent insoluble

[Table 2]

[Table 3]

(Possibility of Industrial Use) The polyester carbonate-based copolymer resin of the present invention is excellent in transparency, solvent solubility and abrasion resistance. Thus, a coating film having excellent optical properties and abrasion resistance can be formed. Further, according to the production method of the present invention, this copolymer resin can be produced by a simple method, and the production cost is low. The copolymer resin of the present invention is useful as a binder resin for an electrophotographic photoreceptor, and the binder resin for an electrophotographic photoreceptor using the copolymer of the present invention has transparency and solvent dissolution. Excellent resistance and wear resistance. Further, the electrophotographic photosensitive member using the binder resin of the present invention is excellent in optical characteristics and long-term life.

Claims

The scope of the claims

(1) Aromatic polyester part composed of an aromatic dicarboxylic acid component and an aromatic diol component (A) 5 to 70% by weight, composed of an aromatic dicarboxylic acid component or an aliphatic dicarboxylic acid component and an aliphatic diol component Polyester part (B) 10 to 75% by weight and aromatic polycarbonate part

(C) 20 to 85% by weight of a polyester carbonate having these components chemically bonded together and having a polymerizable double bond at a terminal.

The copolymer obtained by copolymerizing (D) 99.9 to 90% by weight <½ and a monomer having a double bond copolymerizable therewith (E) 0.1 to 10% by weight A copolymer resin having a number average molecular weight (M n) of 100,000 to 700,000.

(2) The light transmittance in the range of 400 to 800 nm when the coating film has a thickness of 25 jtm is 85% or more. 2. The copolymer resin according to claim 1, wherein the copolymer resin has a solubility in tetrahydrofuran of 10% by weight or more and a viscosity of 10% by weight of a form having a mouth opening at 25 ° C. of 20 Ocp or less.

(3) The coating film formed from the copolymer resin according to claim 1, wherein the light transmittance is 85% or more in a region of 400 to 800 nm when the film thickness is 25 m.

(4) Aromatic polyester portion composed of an aromatic dicarboxylic acid component and an aromatic diol component (A) 5 to 70% by weight, composed of an aromatic dicarboxylic acid component or an aliphatic dicarboxylic acid component and an aliphatic diol component Polyester part (B) 10 to 75% by weight and aromatic polycarbonate part

(C) 20 to 85% by weight, each of which has a chemical bond Polyester resin having a polymerizable double bond at the terminal by reacting a polyester carbonate resin having a functional group capable of reacting with a terminal functional group of the polyester carbonate resin. D), followed by 99.9 to 90% by weight of a polyester carbonate (D) and a monomer (E) O. "! A method for producing a copolymer resin having a number average molecular weight (Mn) of 100,000 to 700,000, characterized by copolymerizing

(5) An electrophotographic photoreceptor having a photosensitive layer on a conductive substrate, characterized in that the photosensitive layer contains the copolymer resin according to claim 1 or 2 as a binder resin. Electrophotographic photoreceptor.

(6) The electrophotographic photosensitive member according to claim 5, wherein the photosensitive layer has a laminated structure of a charge generation layer and a charge transfer layer, and the charge transfer layer is electron donating or electron accepting.

(7) The charge generation layer is composed of a drug selected from phthalocyanines, azo dyes, and perylenes as charge generation agents, and triphenylamines, styryls, and hydrazones as charge transfer agents. 7. An electrophotographic photoreceptor according to claim 6, comprising a drug selected from butanes and butadiene, and the copolymer resin according to claim 1 as a binder resin.