JP2016042169A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor excellent in charge transportability and image stability, and to provide a production method thereof.SOLUTION: In an electrophotographic photoreceptor having a photosensitive layer on a conductive substrate, as a binder resin for the photosensitive layer, a polycarbonate resin composition comprising (A) 99-70 pts.mass of polycarbonate resin and (B) 1-30 pts.mass of polyphenylene ether oligomer having an unsaturated double bond group on a molecular terminal is a highly-sensitive electrophotographic photoreceptor having high compatibility, and being well-soluble into a non-halogen organic solvent.SELECTED DRAWING: None

Description

  The present invention relates to an electrophotographic photoreceptor excellent in charge transportability and image stability and a method for producing the same.

  An organic photoreceptor (hereinafter abbreviated as OPC) is mainly used as an electrophotographic photoreceptor used in copying machines, laser beam printers (hereinafter abbreviated as LBP), fax machines, and the like.

  At present, the mainstream of OPC is a laminated electrophotographic photosensitive member in which a photosensitive layer has a charge generation layer and a charge transport layer, on a metal substrate such as a cylinder made of aluminum or stainless steel or a cylinder or belt made of aluminum-deposited polyester. In addition, a solution in which a binder resin such as polycarbonate or polyarylate, a charge generating agent or a charge transporting agent is dissolved is produced by wet molding represented by a dip coating method.

  In recent years, in order to increase the speed and image quality of copiers and LBPs, improvement of the charge transfer speed in the charge transport layer is required as a means of improving the sensitivity of the electrophotographic photosensitive member. For example, a special charge transport agent having high charge transport performance is used (Patent Document 1), or a method of improving the charge transfer rate in the charge transport layer using a special binder resin incorporating charge transport properties in the main chain ( There is a patent document 2).

  However, although these methods have an effect of improving sensitivity, they are expensive and are not popular in terms of cost effectiveness.

  On the other hand, although polyphenylene ether resin is inferior in mechanical strength, it has a high benzene ring content. Therefore, an electrophotographic photoreceptor that achieves both improved sensitivity and mechanical strength by using a binder resin composition in combination with polycarbonate resin (patented) Document 3) is disclosed. The polyphenylene ether disclosed in this document is not an oligomer, and the molecular terminals are not described.

JP 2011-164659 A JP 7-325409 A JP-A-6-214407 Japanese Patent Laid-Open No. 2003-12796 JP 2006-83364 A

  When the electrophotographic photoreceptor disclosed in Patent Document 3 was tested, the binder resin was dissolved in a chlorinated organic solvent, but the solubility was poor in a non-halogen organic solvent such as toluene and tetrahydrofuran, and the desired properties were obtained. It was found that an electrophotographic photoreceptor cannot be produced. Currently, the non-halogen solvent is mainly used as an organic solvent for the production of an electrophotographic photosensitive member in order to reduce the burden on the environment. The non-halogen solvent of a binder resin composition used in combination with a polyphenylene ether resin and a polycarbonate resin. There has been a demand for improved solubility in water.

An object of the present invention is to provide an electrophotographic photosensitive member that is highly sensitive, inexpensive, and easy to manufacture, and a method for manufacturing the same.

  As a result of intensive studies to solve the above problems, the present inventors have found that a polyphenylene ether oligomer having a specific structure and a specific molecular weight is very compatible with a polycarbonate resin and is well soluble in a non-halogen organic solvent. As a result, the inventors have found that it is suitable for producing a binder resin for a high-sensitivity electrophotographic photosensitive member, and have completed the present invention.

  That is, the present invention relates to the following electrophotographic photosensitive member and a method for producing the same.

<1>
An electrophotographic photosensitive member having a photosensitive layer on a conductive substrate, wherein (A) 99 to 70 parts by mass of a polycarbonate resin as a binder resin of the photosensitive layer, and (B) an unsaturated double bond group at a molecular end. An electrophotographic photoreceptor using a polycarbonate resin composition comprising 1 to 30 parts by mass of a polyphenylene ether oligomer.

<2>
(B) The electrophotographic photosensitive member according to <1>, wherein the polyphenylene ether oligomer has a polystyrene-reduced weight average molecular weight of 1,000 to 6,000 as determined by gel permeation chromatography.

<3>
(A) The electrophotographic photosensitive member according to <1> or <2>, wherein the polycarbonate resin is composed of one represented by the following structural formula (1).

(Wherein R _{1 to} R ₄ are each independently hydrogen, fluorine, chlorine, bromine, iodine, an optionally substituted alkyl group having 1 to 20 carbon atoms, or an optionally substituted carbon number. 6-12 aryl group, C2-C12 alkenyl group which may have a substituent, C1-C5 alkoxy group which may have a substituent, or a substituent A good aralkyl group having 7 to 17 carbon atoms, X is a single bond,

One of them.
Here, R ₅ and R ₆ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, Alternatively, an aryl group having 6 to 12 carbon atoms is represented. R ₅ and R ₆ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₇ and R ₈ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₇ and R ₈ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₉ and R ₁₀ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₉ and R ₁₀ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₁₁ and R ₁₂ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and the number of carbon atoms An alkenyl group having 2 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms is represented. R ₁₃ is an alkylene group of 1 to 9 which may have a substituent.
R ₁₄ and R ₁₅ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₁₄ and R ₁₅ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
a represents an integer of 1 to 20, and b represents an integer of 1 to 500. )

<4>
(A) The polycarbonate resin is bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4- Hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxy-3) -Methylphenyl) -1-phenylethane, 1,1'-biphenyl-4,4'-diol, derived from one or more bisphenols in the group of bis (4-hydroxyphenyl) ether The electrophotographic photosensitive member according to any one of <1> to <3>.

<5>
(B) The electrophotographic photosensitive member according to any one of <1> to <4>, wherein the polyphenylene ether oligomer is represented by the following structural formula (2).

(Wherein R ₁₆ and R ₁₈ are each independently an alkenyl group having 2 to 5 carbon atoms, an aralkyl group having 7 to 17 carbon atoms having an alkenyl group having 2 to 5 carbon atoms as a substituent in an aromatic ring, and 2 carbon atoms) It is an aryl group having 6 to 12 carbon atoms having an alkenyl group having 5 to 5 as a substituent in the aromatic ring, R ₁₇ having an alkylene group having 1 to 12 carbon atoms or a substituent, even if it has a substituent. It represents a group having an aromatic hydrocarbon structure having 6 to 24 carbon atoms, and n1 and n2 represent an integer of 1 to 100.)

<6>
The method for producing an electrophotographic photosensitive member according to any one of <1> to <5>, wherein the photosensitive layer is formed by a dip coating method using a non-halogen organic solvent.

<7>
<6> The method for producing an electrophotographic photosensitive member according to <6>, wherein the photosensitive layer has a laminated structure of a charge generation layer and a charge transport layer.

<8>
The method for producing an electrophotographic photosensitive member according to <6> or <7>, comprising at least one non-halogen organic solvent selected from toluene and tetrahydrofuran.

  In the electrophotographic photoreceptor of the present invention, the charge transport speed of the photosensitive layer is fast and the sensitivity is improved. In addition, compared with the conventional method for producing a high-sensitivity electrophotographic photosensitive member using a binder resin used in combination with a polyphenylene ether resin and a polycarbonate resin, the load on the environment is small, and the production cost can be reduced.

Hereinafter, the present invention will be described in detail.

  The polyphenylene ether oligomer used in the present invention has a structure represented by the structural formula (3). The polyphenylene ether oligomer represented by the structural formula (3) is obtained by, for example, a method of copolymerizing a divalent phenol and a monovalent phenol described in Patent Document 4 in the presence of an amine. 5 can be produced by reacting the vinylbenzyl chloride under basicity with the hydroxyl group at the molecular end.

R ₁₉ and R _{21 at} the molecular ends of the structural formula (3) are each independently an alkenyl group having 2 to 5 carbon atoms, or an aromatic ring having a alkenyl group having 2 to 5 carbon atoms as a substituent and having 7 to 7 carbon atoms. 17 is an aralkyl group, and a vinyl-substituted benzyl group is particularly preferable.

R _{20 in the} structural formula (3) has a substituent, an alkylene group having 1 to 12 carbon atoms, or an aromatic hydrocarbon structure having 6 to 24 carbon atoms that may have a substituent. Although it is a group, those having a biphenyl structure which may have a substituent and a bisphenyl structure which may have a substituent are particularly preferred, and further a group having a biphenyl structure having a plurality of methyl groups is preferred.

  N3 and n4 in Structural Formula (3) are each independently an integer of 1 to 100.

  The molecular weight of the polyphenylene ether oligomer of the present invention is 1,000 to 6,000 in terms of polystyrene-reduced weight average molecular weight by gel permeation chromatography, and in particular, the range of 1,000 to 4,000 is preferable. If it exceeds 6,000, the solubility in a non-halogen organic solvent is poor, and if it is less than 1,000, the strength of the electrophotographic photoreceptor is greatly reduced.

The polycarbonate resin of the present invention can be produced by reacting a bisphenol with a carbonate ester-forming compound, and is a known method used in producing a polycarbonate derived from bisphenol A, for example, Methods such as direct reaction between bisphenols and phosgene (phosgene method) or transesterification reaction between bisphenols and bisaryl carbonate (transesterification method) can be employed.

  The polycarbonate resin of the present invention preferably has a structural unit represented by the following structural formula (4).

In the formula, R _{22 to} R ₂₅ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms, An alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an aralkyl group having 7 to 17 carbon atoms. X ₁ is a single bond or a kind selected from Formula (5).

Here, R ₂₆ and R ₂₇ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, Alternatively, an aryl group having 6 to 12 carbon atoms is represented. R ₂₆ and R ₂₇ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₂₈ and R ₂₉ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₂₈ and R ₂₉ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₃₀ and R ₃₁ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₃₀ and R ₃₁ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₃₂ and R ₃₃ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, a C 1-9 alkyl group, a C 1-5 alkoxy group, a carbon number An alkenyl group having 2 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms is represented. R ₃₄ is an alkylene group of 1 to 9 which may have a substituent.
R ₃₅ and R ₃₆ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₃₅ and R ₃₆ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
c represents an integer of 1 to 20, and d represents an integer of 1 to 500.

Specific examples of bisphenols used in the production of polycarbonate in the present invention include 1,1′-biphenyl-4,4′-diol, bis (4-hydroxyphenyl) methane, and bis (4-hydroxyphenyl) ether. Bis (4-hydroxyphenyl) sulfone, bis (4-hydroxy-3-methylphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) ketone, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) Chlohexane, 1,1-bis (4-hydroxyphenyl) cyclododecane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) ) Propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxy-3-methylphenyl) -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane, 2,2-bis (4-hydroxy-3-allylphenyl) propane, 3,3,5-trimethyl-1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxy-2-) Methyl-5-tert-butylphenyl) -2-methylpropane, 9,9-bis (4-hydroxy-3-ethylphenyl) fluorene, 9 9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9-bis (4-hydroxyphenyl) fluorene, 2,2-bis (4-hydroxyphenyl) hexafluoropropane, 3- (o -Random copolymer of dimethylsiloxane and diphenylsiloxane having hydroxyphenyl) propyl group, α, ω-bis [3- (o-hydroxyphenyl) propyl] polydimethylsiloxane, 4,4 ′-[1,4-phenylene Examples include bis (1-methylethylidene)] bisphenol and 4,4 ′-[1,3-phenylenebis (1-methylethylidene)] bisphenol. These can be used in combination of two or more. Among these, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxy) are particularly preferred. Phenyl) cyclohexane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxy-3-) It is preferably selected from methylphenyl) -1-phenylethane, 1,1′-biphenyl-4,4′-diol, and bis (4-hydroxyphenyl) ether. However, when 2,2-bis (4-hydroxyphenyl) propane, 1,1′-biphenyl-4,4′-diol, or bis (4-hydroxyphenyl) ether is used, In order to improve solubility, it is preferable to copolymerize the remaining bisphenols among the above by 30 mol% or more.

Examples of the carbonic acid ester forming compound used in the production of polycarbonate in the present invention include phosgene, diphenyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl carbonate, and dinaphthyl carbonate. And bisallyl carbonate. Two or more of these compounds can be used in combination.

Furthermore, it is possible to add monofunctional compounds such as phenol, pt-butylphenol, p-cumylphenol, and long-chain alkyl-substituted phenols as molecular weight regulators during the production of the polycarbonate of the present invention and as a degree of polymerization control. is there. If desired, a small amount of an antioxidant, a stabilizer such as sodium sulfite, hydrosulfite, or trisphenyl phosphite, or a branching agent such as phloroglucin or isatin bisphenol may be added.

In the present invention, the polycarbonate used as the electrophotographic photosensitive member binder resin preferably has an intrinsic viscosity [η] of 0.40 dl / g or more and 1.5 dl / g or less. The mixing ratio of (A) polycarbonate and (B) polyphenylene ether oligomer is preferably (A) 99 to 70% by mass, (B) 1 to 30% by mass, and (A) 95 to 80% by mass, (B) 5-20 mass% is preferable. Here, the total of (A) and (B) is 100% by mass. Outside the range where the intrinsic viscosity [η] is applied, the strength and film-forming property are poor. On the other hand, if the mixing ratio of (B) exceeds 30% by mass, cracks are likely to occur in the photoreceptor, and the film-forming property is inferior.

Various ultraviolet absorbers, antioxidants, leveling agents, lubricants, and the like can be added to the binder resin composition of the present invention as desired within a range that maintains the effect.

The electrophotographic photosensitive member of the present invention can be used as a single layer photosensitive layer on a conductive support or a layered type having a functional separation, but the characteristics of the binder resin holding the charge transporting material are the same. It is preferable to use it for the charge transport layer of a multi-layer electrophotographic photosensitive member that can be sufficiently exerted.
When a single photosensitive layer is provided on the conductive support, both the charge transport material and the charge generation material are mixed in the binder resin for use in the photosensitive layer.

The conductive support of the present invention is a polyester film, a phenolic material provided with a conductive material such as aluminum, palladium, tin oxide, zinc oxide, or indium oxide on a metal material such as aluminum, stainless steel, or nickel. Resin, paper, etc. are used. If desired, an undercoat layer that improves smoothness and adhesion may be formed on the surface of these conductive supports.

The charge generation layer of the present invention is formed on a conductive support by a known method. As the charge generation material, for example, organic pigments such as azoxybenzene, disazo, trisazo, benzimidazole, polycyclic quinoline, indigoid, quinacridone, phthalocyanine, perylene, and methine can be used. . These charge generation materials are made of fine particles such as polyvinyl butyral resin, polyvinyl formal resin, silicone resin, polyamide resin, polyester resin, polystyrene resin, polycarbonate resin, polyvinyl acetate resin, polyurethane resin, phenoxy resin, epoxy resin, and various celluloses. Used in a form dispersed in a binder resin.

  The charge transport layer of the present invention is formed of a binder resin composition in which a charge transport material is dispersed on the charge generation layer using a known method. Examples of the charge transport material include polytetracyanoethylene; fluorenone compounds such as 2,4,7-trinitro-9-fluorenone; nitro compounds such as dinitroanthracene; succinic anhydride; maleic anhydride; dibromomaleic anhydride; Triphenylmethane compounds; oxadiazole compounds such as 2,5-di (4-dimethylaminophenyl) -1,3,4-oxadiazole; styryl compounds such as 9- (4-diethylaminostyryl) anthracene Carbazole compounds such as poly-N-vinylcarbazole; pyrazoline compounds such as 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline; 4,4 ′, 4 ″ -tris (N, N-diphenylamino); Triphenylamine, N, N′-bis (3-methylphenyl) -N, N′-bi Amine derivatives such as (phenyl) benzidine, N, N-bis (4-methylphenyl) -4- (2,2-diphenylethenyl) aniline; 1,1-bis (4-diethylaminophenyl) -4,4-diphenyl Conjugated unsaturated compounds such as -1,3-butadiene; hydrazone compounds such as 4- (N, N-diethylamino) benzaldehyde-N, N-diphenylhydrazone; indole compounds, oxazole compounds, isoxazole compounds, thiazoles Compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, pyrazoline compounds, triazole compounds, nitrogen-containing cyclic compounds, condensed polycyclic compounds, etc. The above charge transport materials are used alone. Also, multiple types may be used in combination.

Using the binder resin composition of the present invention, after mixing with a charge transport material, etc., an electrophotographic photoreceptor is formed by known wet molding such as solution casting, casting, spraying, dip coating (dip method), etc. However, the dip coating method is particularly preferable.

The solvent used for the wet molding is a non-halogen organic solvent, for example, aromatic hydrocarbons such as toluene and xylene, ketones such as acetone, methyl ethyl ketone, cyclohexanone, and isophorone, tetrahydrofuran, 1,4-dioxane, Ethers such as ethylene glycol diethyl ether, ethyl cellosolve and anisole, esters such as methyl acetate, ethyl acetate and butyl acetate and other non-halogen organic solvents such as dimethylformamide, dimethylsulfoxide, diethylformamide and N-methyl-2-pyrrolidone Is mentioned. In the present invention, these solvents can be used alone or in combination of two or more. Of these, toluene and tetrahydrofuran, which are easy to remove the solvent and inexpensive, are particularly preferable. When the binder resin composition is dissolved in a solvent to form a charge transport layer, it is preferable to prepare and use a 1 to 30% by weight resin solution.

The mixing ratio of the charge transport material and the binder resin composition is preferably within the range of 10: 1 to 1:10. The thickness of the charge transport layer is 2 to 100 μm, preferably 5 to 40 μm.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.

[Solution permeability]
The charge transport layer forming coating solution was put in a 10 mm glass cell, and the light transmittance at a wavelength of 700 nm was measured with a UV-1800 spectrophotometer manufactured by Shimadzu Corporation. In addition, the transmittance | permeability which put only each solvent in the glass cell was set to 100%, the light transmittance of the solution was correct | amended, and it was set as the solution transmittance | permeability.
If the polymer is not sufficiently dissolved in the solvent, the solution permeability is low.

[Photoconductor characteristics evaluation]
Using a drum tester (PEA-2000LTM manufactured by QEA), set the surface potential to 700 V, the applied voltage to 5.5 kV, charge exposure, draw a light decay curve, and halve exposure amount (E1 / 2) and the residual potential were determined.
The smaller the half exposure value (E1 / 2), the higher the sensitivity.
The smaller the residual potential value, the higher the sensitivity.
When undissolved material was generated and the uniform charge transport layer could not be formed, measurement was impossible.

[Photoreceptor appearance]
When the produced electrophotographic photosensitive member was observed, the case where white turbidity or a yuzu skin-like unevenness was observed was indicated as x, the case where fine cracks were observed was indicated as △, and the case where they were not observed was indicated as ◯.

[Print image appearance]
The produced electrophotographic photosensitive member was incorporated into a commercially available LBP (LP-S210 manufactured by Seiko Epson Corporation), and the appearance of the 50th printed image after continuous black solid printing was observed. The case where one or more white spots (toner-free portions) having a diameter of 1 mm or more could be confirmed was indicated as x, and the case where no whiteness was confirmed was indicated as ◯.

[Measurement method of intrinsic viscosity]
A 0.5 mass / volume% solution of polycarbonate resin in dichloromethane was determined using an Ubbelohde viscosity tube at 20 ° C. and a Huggins constant of 0.45.

[Gel permeation chromatography conditions]
Waters Alliance HPLC system,
2 Shodex 805L columns made by Showa Denko KK
0.25 w / v% chloroform solution sample, 1 ml / min chloroform eluent,
Measured under UV detection conditions at 254 nm.
The polystyrene-reduced weight average molecular weight (Mw) and number average molecular weight (Mn) were determined.

Synthesis example 1
To 1000 ml of 5% (mass / volume) aqueous sodium hydroxide solution, 107.2 g of 1,1-bis (4-hydroxyphenyl) cyclohexane (manufactured by Honshu Chemical Industry Co., Ltd., hereinafter abbreviated as BPZ) was added and dissolved. To this, 500 ml of methylene chloride was added, and while stirring at 15 ° C., 52 g of phosgene was blown in over 50 minutes.
After completion of the blowing, stirring was stopped, and 1.7 g of pt-butylphenol (manufactured by DIC Corporation, hereinafter abbreviated as PTBP) and 100 ml of 5% (w / v) aqueous sodium hydroxide solution were added, and stirring was resumed. . After 10 minutes, 0.4 ml of triethylamine (TEA) was added and stirring was continued for about 1 hour to complete the polymerization.
The polymerization solution was separated into an aqueous phase and an organic phase, the organic phase was neutralized with phosphoric acid, and washing with water was repeated until the conductivity of the washing solution became 10 μS / cm or less. The obtained polymerization resin liquid was dropped into warm water kept at 60 ° C., and the polymer was granulated while removing the solvent by evaporation. The obtained white powdery polymer was filtered and dried at 105 ° C. for 18 hours to obtain a powdery polycarbonate resin (hereinafter abbreviated as PC1).
This polymer had an intrinsic viscosity [η] of 0.45 dl / g obtained as a Huggins constant of 0.45 at a temperature of 20 ° C. in a solution having a concentration of 0.5 g / dl using methylene chloride as a solvent.

Synthesis example 2
Instead of BPZ, 36.5 g of 2,2-bis (4-hydroxyphenyl) propane (Mitsubishi Chemical Corporation, hereinafter abbreviated as BPA) and 2,2-bis (4-hydroxy-3-methylphenyl) propane ( Honshu Kagaku Kogyo Co., Ltd. (hereinafter abbreviated as BPC) 61.4 g was used, and except that PTBP was changed to 1.8 g, an interfacial polycondensation reaction was carried out in the same manner as in Synthesis Example 1 to produce a polycarbonate (abbreviated as PC2 hereinafter, intrinsic viscosity 0. 54 dl / g) was obtained.

Synthesis example 3
Instead of BPZ, 102.4 g of BPC was used and PTBP was changed to 1.4 g, and an interfacial polycondensation reaction was carried out in the same manner as in Synthesis Example 1 to produce polycarbonate (hereinafter abbreviated as PC3, intrinsic viscosity 0.63 dl / g). )

Synthesis example 4
In place of BPZ, 63.6 g of 1,1-bis (4-hydroxy-3-methylphenyl) -1-phenylethane (manufactured by Honshu Chemical Industry Co., Ltd., hereinafter abbreviated as DMBPA) and bis (4-hydroxyphenyl) ether 40.4 g (manufactured by DIC Corporation, hereinafter abbreviated as DHPE) was used, and polycarbonate (hereinafter abbreviated as PC4, intrinsic viscosity 0.75 dl) was subjected to the same interfacial polycondensation reaction as in Synthesis Example 1 except that PTBP was changed to 1.2 g. / G).

Synthesis example 5
Instead of BPZ, 9.3 g of 1,1′-biphenyl-4,4′-diol (Honshu Chemical Industry Co., Ltd., hereinafter abbreviated as BP) and 1,1-bis (4-hydroxyphenyl) ethane (Honshu Chemical) A polycarbonate (hereinafter abbreviated as PC5, intrinsic viscosity 0.57 dl / g) was obtained by an interfacial polycondensation reaction similar to Synthesis Example 1 except that 74.9 g manufactured by Kogyo Co., Ltd., hereinafter abbreviated as BPE) was used.

Synthesis Example 6
Synthesis Example 1 except that 116 g of 1,1-bis (4-hydroxyphenyl) -1-phenylethane (Honshu Chemical Industry Co., Ltd., hereinafter abbreviated as BPAP) was used instead of BPZ, and PTBP was changed to 2.0 g. Was subjected to an interfacial polycondensation reaction in the same manner as above to obtain a polycarbonate (hereinafter abbreviated as PC6, intrinsic viscosity 0.46 dl / g).

Synthesis example 7
BPZ was changed to 80.4 g, and the same interfacial polycondensation reaction as in Synthesis Example 1 was performed except that 20 g of bis (4-hydroxyphenyl) methane (manufactured by Sanko Co., Ltd., hereinafter abbreviated as BPF) was used to produce polycarbonate (hereinafter referred to as “polycarbonate”). PC7, abbreviated as intrinsic viscosity 0.45 dl / g).

Synthesis Example 8 Synthesis of bifunctional phenylene ether oligomer (hereinafter abbreviated as PPE1) CuBr ₂ 3.88 g (17.4 mmol) was added to a 12 L vertical reactor equipped with a stirrer, thermometer, air introduction tube, baffle plate, 0.75 g (4.4 mmol) of N, N′-di-t-butylethylenediamine, 28.04 g (277.6 mmol) of n-butyldimethylamine and 2600 g of toluene were added, and the mixture was stirred at a reaction temperature of 40 ° C. in advance. 129.32 g (0.48 mol) of 2,2′-3,3′-5,5′-hexamethyl- (1,1′-biphenol) -4,4′-diol dissolved in 2300 g of methanol, 292.19 g (2.40 mol) of 6-dimethylphenol, 0.51 g (2.9 mmol) of N, N′-di-t-butylethylenediamine, n- A mixed solution of 10.90 g (108.0 mmol) of tildimethylamine was mixed with nitrogen and air to adjust the oxygen concentration to 8% over 230 minutes while bubbling at a flow rate of 5.2 L / min. The solution was added dropwise and stirred. After completion of the dropwise addition, 1500 g of water in which 19.89 g (52.3 mmol) of ethylenediaminetetraacetic acid tetrasodium was dissolved was added to stop the reaction. The aqueous layer and the organic layer were separated, and the organic layer was washed with a 1N hydrochloric acid aqueous solution and then with pure water. The obtained solution was concentrated to 50% by mass with an evaporator to obtain 833.40 g of a toluene solution of a bifunctional phenylene ether oligomer (PPE1). This toluene solution of PPE1 was used in Synthesis Example 9. Moreover, the toluene solution of PPE1 was dripped in methanol, solidified, solid was collect | recovered by filtration, and it vacuum-dried. The number average molecular weight of PPE1 having a hydroxyl group at the end was 930, the weight average molecular weight was 1460, and the hydroxyl equivalent was 465.

Synthesis Example 9 Synthesis of bifunctional phenylene ether oligomer (hereinafter abbreviated as PPE2) In a reactor equipped with a stirrer, a thermometer, and a reflux tube, 833.40 g of toluene solution of oligomer PPE1 obtained in Synthesis Example 8 and vinylbenzyl 160.80 g of chloride (CMS-P manufactured by Seimi Chemical Co., Ltd.), 1600 g of methylene chloride, 12.95 g of benzyldimethylamine, 420 g of pure water, and 175.9 g of 30.5 mass% NaOH aqueous solution were charged and stirred at a reaction temperature of 40 ° C. Went. After stirring for 24 hours, the organic layer was washed with a 1N aqueous hydrochloric acid solution and then with pure water. The obtained solution was concentrated with an evaporator, dropped into methanol and solidified, and the solid was collected by filtration and vacuum-dried to obtain 501.43 g of a vinyl-terminated oligomer PPE2. The number average molecular weight of this PPE2 was 1165, and the weight average molecular weight was 1630.

Synthesis Example 10 Synthesis of bifunctional phenylene ether oligomer (hereinafter abbreviated as PPE3) CuBr ₂ 9.36 g (42.1 mmol) was added to a 12 L vertical reactor equipped with a stirrer, thermometer, air introduction tube, baffle plate, N, N′-di-t-butylethylenediamine 1.81 g (10.5 mmol), n-butyldimethylamine 67.77 g (671.0 mmol), and toluene 2600 g were charged and stirred at a reaction temperature of 40 ° C. in advance. 129.32 g (0.48 mol) of 2,2′-3,3′-5,5′-hexamethyl- (1,1′-biphenol) -4,4′-diol dissolved in 2300 g of methanol, 6-dimethylphenol 878.4 g (7.2 mol), N, N′-di-t-butylethylenediamine 1.22 g (7.2 mmol), n- A mixed solution of 26.35 g (260.9 mmol) of tildimethylamine was mixed with nitrogen and air to adjust the oxygen concentration to 8% over 230 minutes while bubbling at a flow rate of 5.2 L / min. The solution was added dropwise and stirred. After completion of the dropwise addition, 1500 g of water in which 48.06 g (126.4 mmol) of ethylenediaminetetraacetic acid tetrasodium was dissolved was added to stop the reaction. The aqueous layer and the organic layer were separated, and the organic layer was washed with a 1N hydrochloric acid aqueous solution and then with pure water. The obtained solution was concentrated to 50% by mass with an evaporator to obtain 1981 g of a toluene solution of a bifunctional phenylene ether oligomer having a terminal hydroxyl group (hereinafter abbreviated as PPE3). The oligomer PPE3 had a number average molecular weight of 1975, a weight average molecular weight of 3514, and a hydroxyl group equivalent of 990.

Synthesis Example 11 Synthesis of bifunctional phenylene ether oligomer (hereinafter abbreviated as PPE4) In a reactor equipped with a stirrer, a thermometer, and a reflux tube, 833.40 g of a toluene solution of PPE3, vinylbenzyl chloride (CMS-P) 76. 7 g, 1600 g of methylene chloride, 6.2 g of benzyldimethylamine, 199.5 g of pure water, and 83.6 g of a 30.5 mass% NaOH aqueous solution were charged and stirred at a reaction temperature of 40 ° C. After stirring for 24 hours, the organic layer was washed with a 1N aqueous hydrochloric acid solution and then with pure water. The obtained solution was concentrated with an evaporator, dropped into methanol to solidify, and the solid was collected by filtration and vacuum dried to obtain 450.1 g of an oligomer having a vinyl group at the end (hereinafter abbreviated as PPE4). . The number average molecular weight of this PPE4 was 2250, and the weight average molecular weight was 3920.

<Manufacture of coating liquid for undercoat layer formation>
A polyamide resin (“Alamin CM-8000” manufactured by Toray Industries, Inc.) is stirred and mixed in a mixed solvent having a methanol / 1-butanol mass ratio of 7/3, and the resulting mixture is applied to form an undercoat layer with a solid content concentration of 5 mass%. A liquid was prepared.

<Manufacture of coating solution for forming charge generation layer>
As a charge generation substance, 11 parts by mass of Y-type oxytitanium phthalocyanine (manufactured by SENSIENT TECNOLOGY), 18 parts by mass of tetrahydrofuran, and 2 parts by mass of water were mixed and dissolved by stirring with a roller mill. Subsequently, 8 parts by mass of alkyl acetalized polyvinyl butyral (trade name “Denka Butyral” BX-1), 500 parts by mass of tetrahydrofuran, and 6 parts by mass of water were mixed with this micronized treatment liquid to form a charge generation layer. A coating solution was prepared.

Example 1
Put the coating solution for forming the undercoat layer in a graduated cylinder, immerse an aluminum tube (diameter 24 mm, length 252 mm, 0.8 mm thickness) in the coating solution, perform dip coating, and air dry at room temperature to about 0.5 μm. A thick subbing layer was obtained.
Subsequently, the charge generating layer forming coating solution is put in another measuring cylinder, dip coated on the aluminum tube coated with the undercoat layer, and air-dried at room temperature to obtain a charge generating layer of about 0.3 μm. It was.
Next, 90 parts by mass of polycarbonate resin PC1 and 10 parts by mass of PPE2, N, N-bis (4-methylphenyl) -4- (2,2-diphenylethenyl) aniline (Takasago International Corporation) as a charge transport material 80 parts by mass), 1 part by mass of dibutylhydroxytoluene as an antioxidant, and 0.05 parts by mass of silicone oil (trade name: KF96) as leveling agent, 100 parts by mass of tetrahydrofuran and 380 toluene A charge transport layer forming coating solution was prepared by dissolving in a mixed solvent with parts by mass. A part of the charge transport layer forming solution was sampled, and the solution permeability was measured.
Also, the coating solution for forming the charge transport layer is placed in a graduated cylinder, dip-coated on the aluminum tube coated with the charge generation layer, air dried at room temperature, and then dried at 125 ° C. for 20 minutes to produce an electrophotographic photoreceptor. did.
After the appearance of the obtained electrophotographic photoreceptor was observed, E1 / 2 and the residual potential were measured with a drum tester, set on a commercially available LBP, printed, and the appearance of the printed image was observed.

Example 2
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that PC2 was used instead of PC1 and PPE4 was used instead of PPE2.

Example 3
Production of electrophotographic photosensitive member and evaluation of physical properties were the same as in Example 1 except that 80 parts by mass of PC3 was used instead of 90 parts by mass of PC1, and 20 parts by mass of PPE4 was used instead of 10 parts by mass of PPE2. Went.

Example 4
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that 95 parts by mass of PC4 was used instead of 90 parts by mass of PC1, and PPE2 was changed to 5 parts by mass.

Example 5
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that PC5 was used instead of PC1 and PPE4 was used instead of PPE2.

Example 6
Except that PC6 was used instead of PC1, electrophotographic photosensitive member was prepared and physical properties were evaluated in the same manner as in Example 1.

Example 7
The electrophotographic photosensitive member was produced and the physical properties were evaluated in the same manner as in Example 1 except that PC7 was used instead of PC1 and PPE4 was used instead of PPE2.

Example 8
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that PC1 was changed to 98 parts by mass and PPE2 was changed to 2 parts by mass.

Example 9
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that PC1 was changed to 70 parts by mass and 10 parts by mass of PPE2 was changed to 30 parts by mass of PPE4.

Example 10
An electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 3 except that methyl ethyl ketone was used instead of tetrahydrofuran and ortho-xylene was used instead of toluene.

Comparative Example 1
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that a commercially available polyphenylene ether resin (PX100F, Mw18700, hereinafter abbreviated as PPE5) manufactured by Mitsubishi Gas Chemical Co., Ltd. was used instead of PPE2. It was.

Comparative Example 2
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 2 except that a commercially available polyphenylene ether resin (PX100L, Mw24200, abbreviated as PPE6 hereinafter) manufactured by Mitsubishi Gas Chemical Co., Ltd. was used instead of PPE4. It was.

Comparative Example 3
In the same manner as in Example 3 except that PPE5 was used instead of PPE2, electrophotographic photosensitive member preparation and physical property evaluation were performed.

Comparative Example 4
In the same manner as in Example 4 except that PPE5 was used instead of PPE2, electrophotographic photosensitive member preparation and physical property evaluation were performed.

Comparative Example 5
An electrophotographic photosensitive member was prepared and physical properties were evaluated in the same manner as in Example 5 except that PPE1 was used instead of PPE4.

Comparative Example 6
The electrophotographic photosensitive member was prepared and the physical properties were evaluated in the same manner as in Example 1 except that PC1 was changed to 100 parts by mass and PPE2 was not used.

Comparative Example 7
Except that PC1 was changed to 99.2 parts by mass and PPE2 was changed to 0.8 parts by mass, production of an electrophotographic photosensitive member and evaluation of each physical property were performed in the same manner as in Example 1.

Comparative Example 8
Except that PC1 was changed to 65 parts by mass and PPE2 was changed to 35 parts by mass, electrophotographic photosensitive member production and physical property evaluation were performed in the same manner as in Example 1.

Comparative Example 9
In the same manner as in Example 10 except that PPE5 was used instead of PPE2, electrophotographic photosensitive member preparation and physical property evaluation were performed.

  The results of Examples 1 to 10 and Comparative Examples 1 to 9 are shown in Table 1.

The electrophotographic photoreceptor of the present invention contains a specific polyphenylene ether oligomer in a binder resin, so that it can be easily wet-molded using a non-halogen organic solvent, has good charge transportability, high sensitivity, and stability. An image is obtained. In addition, it can be manufactured at a lower cost than conventional high-sensitivity electrophotographic photosensitive members, and is particularly suitable for low / medium-speed copying machines, LBPs, and complex machines that require cost performance.

Claims (8)

  An electrophotographic photosensitive member having a photosensitive layer on a conductive substrate, wherein (A) 99 to 70 parts by mass of a polycarbonate resin as a binder resin of the photosensitive layer, and (B) an unsaturated double bond group at a molecular end. An electrophotographic photoreceptor using a polycarbonate resin composition comprising 1 to 30 parts by mass of a polyphenylene ether oligomer.   (B) The electrophotographic photosensitive member according to claim 1, wherein the polyphenylene ether oligomer has a polystyrene-reduced weight average molecular weight of 1,000 to 6,000 as determined by gel permeation chromatography. (A) The electrophotographic photosensitive member according to claim 1 or 2, wherein the polycarbonate resin is composed of one represented by the following structural formula (1).

(Wherein R _{1 to} R ₄ are each independently hydrogen, fluorine, chlorine, bromine, iodine, an optionally substituted alkyl group having 1 to 20 carbon atoms, or an optionally substituted carbon number. 6-12 aryl group, C2-C12 alkenyl group which may have a substituent, C1-C5 alkoxy group which may have a substituent, or a substituent A good aralkyl group having 7 to 17 carbon atoms, X is a single bond,

One of them.
Here, R ₅ and R ₆ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, Alternatively, an aryl group having 6 to 12 carbon atoms is represented. R ₅ and R ₆ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₇ and R ₈ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₇ and R ₈ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₉ and R ₁₀ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₉ and R ₁₀ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
R ₁₁ and R ₁₂ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and the number of carbon atoms An alkenyl group having 2 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms is represented. R ₁₃ is an alkylene group of 1 to 9 which may have a substituent.
R ₁₄ and R ₁₅ are each independently hydrogen, fluorine, chlorine, bromine, iodine, each having a substituent, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or Represents a C6-C12 aryl group. R ₁₄ and R ₁₅ may combine to form a carbocyclic ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements.
a represents an integer of 1 to 20, and b represents an integer of 1 to 500. ) (A) The polycarbonate resin is bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4- Hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxy-3) -Methylphenyl) -1-phenylethane, 1,1'-biphenyl-4,4'-diol, derived from one or more bisphenols in the group of bis (4-hydroxyphenyl) ether The electrophotographic photosensitive member according to claim 1. (B) The electrophotographic photosensitive member according to any one of claims 1 to 4, wherein the polyphenylene ether oligomer is represented by the following structural formula (2).

(Wherein R ₁₆ and R ₁₈ are each independently an alkenyl group having 2 to 5 carbon atoms, an aralkyl group having 7 to 17 carbon atoms having an alkenyl group having 2 to 5 carbon atoms as a substituent in an aromatic ring, and 2 carbon atoms) It is an aryl group having 6 to 12 carbon atoms having an alkenyl group having 5 to 5 as a substituent in the aromatic ring, and R ₁₇ has an optionally substituted alkylene group having 1 to 12 carbon atoms and a substituent. It represents a group having an aromatic hydrocarbon structure having 6 to 24 carbon atoms, and n1 and n2 represent an integer of 1 to 100.) 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 transport layer. The method for producing an electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer is formed by a dip coating method using a non-halogen organic solvent. The method for producing an electrophotographic photosensitive member according to claim 7, wherein the non-halogen organic solvent contains at least one selected from toluene and tetrahydrofuran.