JPH0959365A - Purification of charge transportable resin, electron photographic photosensitive body and electron photographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To purify an impurity-containing electron transportable resin to a resin suitable as an electron photographic sensitive body, enhanced in film forming properties, pot life and abrasion resistance and reduced in residual potential by removing impurities by dropping a specific solvent to a solution of the impurity-containing resin and reprecipitating the resin. SOLUTION: In this purification of a charge transportable resin, impurities are removed by dropping a solvent (e.g. distilled water, methanol, ethanol, acetone) capable of precipitating the resin to a solution of the charge transportable resin e.g. a charge transportable polycarbonate resin or a polyester resin expressed by formula I [R1 and R2 are each H, an alkyl, an alkoxy, etc.; X is a (substituted) divalent aromatic residue; T is a 1-10C (branched) divalent hydrocarbon residue; (k) and (l) are each 0 or 1] or formula II (R3 and R4 are each R1 ) and reprecipitating the resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying a charge transporting resin, an electrophotographic photoreceptor and an electrophotographic apparatus using the method.

[0002]

2. Description of the Related Art Charge-transporting resins represented by polyvinylcarbazole (PVK) are photoconductive materials for electrophotographic photoreceptors or proceedings of the 36th Joint Lecture on Applied Physics.
It is a promising organic electroluminescent device material as described in p-K-12 (1990). These form a layer together and are used as a charge transport layer. As materials for forming the charge transport layer, a charge transport resin represented by PVK and a charge transporting low molecular weight compound are dispersed in the resin. It is well known that the above-mentioned low molecular weight dispersion system. Further, in an organic electroluminescence device, it is general to use a low-molecular charge transport material by vapor deposition. Among them, low-molecular-weight dispersion type ones have become the mainstream in electrophotographic photoreceptors in particular because they have a variety of materials and can easily obtain high-performance ones. With respect to electrophotographic photoreceptors, in recent years, with the high performance of organic photoreceptors, they have come to be used in high-speed copying machines and printers. The performance is not sufficient, and it is earnestly desired to further extend the life of the organic photoconductor. One of the important factors that determines the life of an organic photoreceptor is the wear of the charge transport layer. Regarding the current mainstream charge transport layer of low molecular weight dispersion type, it is being obtained that it has sufficiently satisfactory electrical properties, but since the low molecular weight compound is dispersed in the resin, it is essential The mechanical strength is inferior, and it is weak against abrasion. Further, in the case of the organic electroluminescence device, there is a drawback that the low molecular weight charge transport material is melted by the generated Joule heat and the morphology change of the film is likely to occur due to crystallization or the like.

On the other hand, charge-transporting resins are currently being actively studied because they have the potential to greatly improve the above-mentioned drawbacks. For example, US Pat. No. 4,806,443
US Pat. No. 4,806,444 discloses a polycarbonate obtained by polymerizing a specific dihydroxyarylamine with bischloroformate, and US Pat. No. 4,806,444 discloses a polymerization of specific dihydroxyarylamine with phosgene. Polycarbonates are disclosed. U.S. Pat. No. 4,801,517 discloses a polycarbonate obtained by polymerizing bishydroxyalkylarylamine with bischloroformate or phosgene. U.S. Pat. No. 4,937,165 and U.S. Pat. No. 4,959,288 discloses a polycarbonate obtained by polymerization of a specific dihydroxyarylamine or bishydroxyalkylarylamine with bischloroformate, or a polyester obtained by polymerization of a bisacyl halide. Further, US Pat. No. 5,034,296 discloses polycarbonates of arylamines having a specific fluorene skeleton,
Alternatively, the polyester is also disclosed in U.S. Pat.
No. 482 discloses a polyurethane.
JP-B-59-28903 discloses a polyester having a specific bisstyrylbisarylamine as a main chain. Also, JP-A-61-2095
No. 3, JP-A-1-134456, JP-A-1-134456
JP-A-134457, JP-A-1-134462,
Japanese Unexamined Patent Publication No. Hei 4-133065, Hei 4-13306
No. 6, etc. also propose a resin having a pendant charge-transporting substituent such as hydrazone or triarylamine, and a photoreceptor using the same. In particular, resins with a tetraarylbenzidine skeleton are
ational Congress on Advances in Non-impact Printin
g Technologies, 306, (1990). ”, it has high mobility and high practicality.

[0004]

By the way, in the polymerization reaction of the charge transporting resin, an oligomer or the like having a lower molecular weight than the desired molecular weight is likely to be produced as a by-product. When this low molecular weight component is mixed, it may cause problems in production such as deterioration of film forming property and decrease of pot life, and the number of end groups that may form a trap may increase. As a result, problems such as an increase in residual potential, a decrease in repeated stability, and a decrease in abrasion resistance tend to occur as problems in electrophotographic characteristics. In order to solve these problems, it is necessary to purify the charge transporting resin after the polymerization reaction. As a general method for purifying a resin, a Soxhlet extraction method for extracting and removing soluble impurities and a reprecipitation method for dropping a resin solution into an excessive precipitation solvent while stirring to precipitate the resin solution are known. However, when the substance to be removed and the resin to be purified have similar properties, the Soxhlet extraction method and the reprecipitation method have drawbacks such as difficulty in removal or repeated purification. An object of the present invention is to solve these problems, and it is an object of the present invention to provide a purification method capable of effectively removing low molecular weight components. Another object of the present invention is to provide an electrophotographic photosensitive member and an electrophotographic apparatus which have excellent printing durability and high stability when repeatedly copied.

[0005]

Means for Solving the Problems As a result of intensive investigations by the present inventors in view of the above-mentioned drawbacks, a solvent capable of precipitating the charge-transporting resin was dropped into a solution of the charge-transporting resin obtained by synthesis. It was found that by doing so, low molecular weight components can be effectively removed. Furthermore, the charge-transporting resin purified by this method is excellent in charge-transporting property, stability of electric characteristics, and mechanical abrasion, and an organic electronic device using the same, particularly an electrophotographic photoreceptor, has excellent electric characteristics and high They have found that durability can be realized, and have completed the present invention.

Therefore, in the method for purifying a charge-transporting resin of the present invention, a solvent capable of precipitating the charge-transporting resin is dropped into a solution of the charge-transporting resin containing a low molecular weight component as a by-product. It is characterized by reprecipitation and removal of impurities. Further, the electrophotographic photosensitive member of the present invention is characterized in that the surface layer contains the charge-transporting polycarbonate resin or the charge-transporting polyester resin obtained by the above-described method for purifying the charge-transporting resin. Further, the electrophotographic apparatus of the present invention has a photoconductor and a charging member which is arranged so as to be in contact with the photoconductor and to which a voltage is applied, and the photoconductor is made of the above charge transporting resin. It is characterized by comprising an electrophotographic photoreceptor containing a charge-transporting polycarbonate resin or charge-transporting polyester resin obtained by a purification method in a surface layer.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. First, the synthesized charge transporting resin containing a low molecular weight component as a by-product is dissolved in a suitable solvent to obtain a charge transporting resin solution. As the solvent, any solvent can be used as long as it dissolves the charge transporting resin, but tetrahydrofuran, dichloromethane, chloroform, toluene, monochlorobenzene and the like are preferable. The dissolved concentration of the charge transporting resin is 100
0.1 to 20 parts by weight, preferably 0.
It is set in the range of 5 to 5 parts by weight. The dissolution temperature is set to room temperature or lower than the boiling point of the solvent used. The obtained charge-transporting resin solution can be filtered to remove insoluble matter, if necessary. While stirring the obtained charge transporting resin solution with a magnetic stirrer, a mechanical stirrer, or the like, a solvent capable of precipitating the charge transporting resin (hereinafter, referred to as “precipitation solvent”) is dropped therein. At that time, the temperature of the charge transporting resin solution is 0 to 40 ° C., preferably 1
It is set between 0 and 30 ° C. As the precipitation solvent, any solvent can be used as long as it can precipitate the charge transporting resin, but distilled water, methanol, ethanol, acetone and the like are preferable. The temperature of the precipitation solvent is 0-4
The temperature is set to 0 ° C, preferably 10 to 30 ° C. The dropping rate of the precipitation solvent can be set arbitrarily. The amount of the precipitation solvent added dropwise is such that the desired charge transporting resin can be precipitated, and
The amount can be arbitrarily set as long as it does not precipitate the low molecular weight component to be removed. When the dropping of the precipitation solvent is started, the components having a large molecular weight which are likely to be precipitated are sequentially precipitated. The dropping of the precipitation solvent is stopped before the low molecular weight components to be removed have precipitated. The obtained precipitate is separated from the solution portion by a method such as filtration. When the separated precipitate is in the form of starch syrup, it is difficult to dry even if it is dried under reduced pressure, and the solvent is likely to remain, so that it can be obtained by dissolving it in a solvent that dissolves it as it is or after appropriately drying. Alternatively, the resin solution may be dropped into a precipitation solvent such as water or methanol with stirring to form a fibrous precipitate.

In the present invention, as the charge transporting resin, any conventionally known charge transporting resin can be used, but a charge transporting polycarbonate resin or a charge transporting polyester resin is particularly preferable. Examples of the charge transporting polycarbonate resin and the charge transporting polyester resin include, for example, U.S. Pat. Nos. 4,806,443, 4,806,444, 4,801,517, and 4,937. No. 165, No. 4,959,288,
No. 5,034,296, Japanese Patent Application No. 6-1517
No. 76, Japanese Patent Application No. 6-219599, Japanese Patent Application No. 6-329
No. 854, Japanese Patent Application No. 6-329853, Japanese Patent Application No. 6-70.
A charge transporting resin composed of a repeating unit containing at least one of the partial structures represented by the following general formula (I-1) or (I-2) described in Japanese Patent Application No. 232 and Japanese Patent Application No. 7-161608 is preferable. .

[0009]

Embedded image (Here, R ₁ to R ₄ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a substituted amino group, a halogen atom, or a substituted or unsubstituted aryl group, and X is a substituted or unsubstituted divalent group. Represents an aromatic group of
Represents a divalent hydrocarbon group having 1 to 10 carbon atoms which may be branched, and k and l each represent 0 or 1. )

In the above general formula, the following can be exemplified as specific structural examples of the hydrocarbon group represented by the group T. The arylamine skeleton may be bonded to either side. For example, when written as T-2r, it is on the right side of the structure T-2, and when written as T-21, it is a tetraaryl on the left side of the structure T-2. It shall indicate that the benzidine skeleton is bonded.

[0011]

Embedded image

[0012]

Embedded image

Further, as X, the following groups (1) to (7)
Selected from the list below.

[Chemical 6] [In the formula, R ₅ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted aralkyl group, and R _{6 to} R ₁₂ each represent a hydrogen atom, C1-C4 alkyl group, C1-C1
4, an alkoxy group, a substituted or unsubstituted phenyl group,
It represents a substituted or unsubstituted aralkyl group or a halogen atom, a represents 0 or 1, and V represents a group selected from the following groups (8) to (17).

[0014]

[Chemical 7] (B means an integer of 1 to 10 and c means an integer of 1 to 3)]

Further, Y and Z are the following groups (18) to
Represents a group selected from (24).

Embedded image (In the formula, R ₁₃ and R ₁₄ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted aralkyl group, or Represents a halogen atom, d and e
Each represents an integer of 1 to 10, f and g each represent an integer of 0, 1 or 2, h and i each represent 0 or 1, and V has the same meaning as described above. )

Of these, polymers in which X has a biphenyl structure represented by the following structural formula (V) or (VI) are
`` The Sixth International Congress on Advances in
Non-impact Printing Technologies, 306, (1990) ”has high mobility and is particularly preferable.

Embedded image

More specifically, the following general formula (I
The charge-transporting polycarbonate resin and the charge-transporting polyester resin represented by I) to (IV) are preferable.

Embedded image [Where A is the above general formula (I-1) or (I-2)
Represents a partial structure represented by, B is -O- (Y'-O)
_{m '-} or an -Z'- (However, Y' and Z '
Each represents a divalent hydrocarbon group, and m ′ represents an integer of 1 to 5. ), Y and Z each represent a divalent hydrocarbon group, m represents an integer of 1 to 5, n represents 0 or 1, and p, p ′ and p ″ represent an integer of 5 to 5000. Represents.]

Specific examples of the charge transporting resin in the present invention are shown in the table below. In addition, Table 1 to Table 5 show the general formula (I-1)
Is an example of the partial structure represented by, and Tables 6 to 10 are examples of the partial structure represented by the general formula (I-2). Further, Tables 11 to 12 exemplify the charge transporting polyester resin represented by the general formula (II), Table 13 exemplifies the charge transporting polyester resin represented by the general formula (III), and Table 14
Are examples of the charge transporting polycarbonate resin represented by the general formula (IV).

Examples of the partial structure represented by the above general formula (I-1)

[Table 1]

[0020]

[Table 2]

[0021]

[Table 3]

[0022]

[Table 4]

[0023]

[Table 5]

Examples of the partial structure represented by the above general formula (I-2)

[Table 6]

[0025]

[Table 7]

[0026]

[Table 8]

[0027]

[Table 9]

[0028]

[Table 10]

Examples of the charge transporting polyester resin represented by the above general formula (II)

[Table 11]

[0030]

[Table 12]

Examples of the charge transporting polyester resin represented by the above general formula (III)

[Table 13]

Examples of the charge transporting polycarbonate resin represented by the above general formula (IV)

[Table 14]

The synthesis of the charge-transporting resin of the present invention is described in the above-mentioned document, but the case of synthesizing the charge-transporting polyester resin will be described below as an example. The charge-transporting polyester resin has the following structural formula (VII
) Or (VIII), at least one of the charge-transporting monomers can be used for the synthesis by a known method described in, for example, Vol. 28, Experimental Chemistry Course, 4th edition.

[0034]

Embedded image [In the formula, R ₁ to R ₄ are each independently a hydrogen atom,
An alkyl group, an alkoxy group, a substituted amino group, a halogen atom, or a substituted or unsubstituted aryl group, X
Represents a substituted or unsubstituted divalent aromatic group, T represents a branched divalent hydrocarbon group having 1 to 10 carbon atoms, k and l are 0 or 1, and E is a hydroxyl group. Represents a halogen atom or a group —O—R ₁₅ . (However, R ₁₅
Represents an alkyl group, a substituted or unsubstituted aryl group, or an aralkyl group. )]

(1) When E is a hydroxyl group When E is a hydroxyl group, dihydric alcohols represented by HO- (YO) _m- H are mixed in approximately equivalent amounts and polymerized using an acid catalyst. As the acid catalyst, those used for ordinary esterification reaction such as sulfuric acid, toluenesulfonic acid, trifluoroacetic acid, etc. can be used, and 1/10000 to 1/10 parts by weight, preferably 1 part by weight of the charge transporting monomer. Is 1 /
It is used in the range of 1000 to 1/50 parts by weight. In order to remove water generated during the polymerization, it is preferable to use a solvent which can be azeotroped with water, such as toluene, chlorobenzene and 1
-Chloronaphthalene or the like is effective, and is 1 to 100 parts by weight, preferably 2 parts by weight with respect to 1 part by weight of the charge transporting monomer.
It is used in the range of ５０50 parts by weight. The reaction temperature can be arbitrarily set, but the reaction is preferably performed at the boiling point of the solvent in order to remove water generated during the polymerization. After completion of the reaction, if no solvent is used, the solvent is dissolved in a soluble solvent. When a solvent is used, the reaction solution as it is is dropped into alcohols such as methanol and ethanol, or into a poor solvent in which a polymer such as acetone is difficult to dissolve, to deposit the charge transporting resin, and the charge transporting resin is deposited. After separation, wash thoroughly with water or organic solvent and dry. Further, if necessary, the reprecipitation treatment of dissolving in a suitable organic solvent, dropping in a poor solvent and precipitating the charge transporting resin may be repeated.
The reprecipitation treatment is preferably carried out with a mechanical stirrer or the like while efficiently stirring. The solvent that dissolves the charge transporting resin during the reprecipitation treatment is 1 to 100 parts by weight, preferably 2 to 1 part by weight of the charge transporting resin.
Used in the range of 50 parts by weight. Further, the poor solvent is 1 to 1000 parts by weight with respect to 1 part by weight of the charge transporting polymer,
It is preferably used in the range of 10 to 500 parts by weight.

(2) When E is a halogen When E is a halogen, dihydric alcohols represented by HO- (YO) _m- H are mixed in approximately equivalent amounts, and an organic basic compound such as pyridine or triethylamine is used. Polymerize using a catalyst. The organic basic catalyst is used in an amount of 1 to 10 equivalents, preferably 2 to 5 equivalents, per equivalent of the charge transporting monomer. As the solvent, methylene chloride, tetrahydrofuran (THF), toluene, chlorobenzene, 1-chloronaphthalene, etc. are effective, and the charge transporting monomer 1
1 to 100 parts by weight, preferably 2 to 5 parts by weight
It is used in the range of 0 parts by weight. The reaction temperature can be set arbitrarily. After the polymerization, it is reprecipitated and purified as described above.
Further, in the case of a dihydric alcohol having a high acidity such as bisphenol, an interfacial polymerization method can also be used. That is, dihydric alcohols are added to water, an equivalent amount or more of a base is added and dissolved, and then the dihydric alcohols and an equivalent amount of the charge transporting monomer solution are added with vigorous stirring to perform polymerization. At this time, water is 1 to 1000 parts by weight, preferably 2 to 50 parts by weight with respect to 1 part by weight of the dihydric alcohol.
It is used in the range of 0 parts by weight. Solvents for dissolving the charge transporting monomer include methylene chloride, dichloroethane, trichloroethane, toluene, chlorobenzene, 1
-Chloronaphthalene is effective. The reaction temperature can be set arbitrarily, and it is effective to use a phase transfer catalyst such as an ammonium salt or a sulfonium salt to promote the reaction. The phase transfer catalyst is used in an amount of 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, based on 1 part by weight of the charge transporting monomer.

(3) When E is --O--R ₁₅ When E is --O--R _15, a dihydric alcohol represented by HO-(YO) _m --H is added in excess and sulfuric acid is added. , An inorganic acid such as phosphoric acid, a titanium alkoxide, an acetate or carbonate such as calcium and cobalt, or an oxide of zinc or lead is heated as a catalyst, and transesterification can be performed. Two
Polyhydric alcohols are equivalent to one equivalent of the charge transporting monomer,
It is used in the range of 2 to 100 equivalents, preferably 3 to 50 equivalents. The catalyst is 1 part by weight of the charge transporting monomer,
1/10000 to 1 part by weight, preferably 1/1000 to
It is used in the range of ½ part by weight. The reaction temperature is 2
The reaction is carried out at a temperature of 00 to 300 ° C. and the group —O—R ₁₅ to the group —O— (Y
After completion of transesterification to -O) _m -H, HO- (Y-
O) In order to accelerate the polymerization due to elimination of _m- H, 0.01
~ 100 mmHg, preferably 0.05-20 mm
It is preferable to reduce the pressure to Hg for the reaction. Also, HO
- _(Y-O) with m -H and high boiling point solvent such as azeotropic 1-chloronaphthalene under normal pressure HO- _{(Y-O) m}
It is also possible to react while removing -H azeotropically.

The charge-transporting resin represented by the general formula (III) can be synthesized as follows. In each of the above cases, a dihydric alcohol is added in excess and reacted to produce a compound represented by the following structural formula (IX) or (X), which is then used as a charge-transporting monomer. ) And 2
The charge-transporting resin can be obtained by reacting with a divalent carboxylic acid or a divalent carboxylic acid halide.

[0039]

[Chemical 12] (In the formula, R ₁ to R ₄ are each independently a hydrogen atom,
An alkyl group, an alkoxy group, a substituted amino group, a halogen atom, or a substituted or unsubstituted aryl group, X
Represents a substituted or unsubstituted divalent aromatic group, Y represents a divalent hydrocarbon group, T represents an optionally branched divalent hydrocarbon group having 1 to 10 carbon atoms, m represents an integer of 1 to 5, and k and l are 0 and 1, respectively. In the present invention, if the polymerization degrees p, p ′ and p ″ of the charge-transporting resin are too low, the film-forming property is poor and a strong film is difficult to obtain, and if it is too high, the solubility in a solvent is low. Since the workability is deteriorated, those having a range of 5 to 5000 are used, preferably 10 to 3000, more preferably 15
It is set in the range of up to 1000. Further, the terminal of the charge transporting resin can be modified if desired.

Next, the electrophotographic photosensitive member of the present invention will be described. 1 to 7 are schematic views showing a cross section of the electrophotographic photosensitive member of the present invention. In FIG. 1, the charge generation layer 1 is provided on the conductive support 3, and the charge transport layer 2 is provided thereon. In FIG. 2, the conductive support 3
An undercoat layer 4 is provided on the upper side, and in FIG. 3, a protective layer 5 is provided on the surface. Further, in FIG. 4, both the undercoat layer 4 and the protective layer 5 are provided. 5 to 7 show a single-layer structure composed of the photoconductive layer 6. In FIG. 6, the undercoat layer 4 is provided. In FIG. 7, both the undercoat layer 4 and the protective layer 5 are provided. Has been. In the present invention, the charge-transporting resin purified as described above can be used in any of the structures shown in FIGS. 1 to 7, but it is contained in the layer forming the surface.

Examples of the conductive support include metals such as aluminum, nickel, chromium and stainless steel, and aluminum, titanium, nickel, chromium, stainless steel, gold, vanadium, tin oxide, indium oxide and ITO.
And plastic films coated with or impregnated with a conductivity-imparting agent, and plastic films and the like. These conductive supports are
It may be used in any suitable shape such as a drum shape, a sheet shape, or a plate shape, but is not limited thereto. Further, if necessary, the surface of the conductive support can be subjected to various treatments within a range that does not affect the image quality. For example, surface oxidation treatment and chemical treatment, and coloring treatment,
Alternatively, irregular reflection processing such as graining can be performed. Further, an undercoat layer may be further provided between the conductive support and the charge generation layer. This undercoat layer prevents injection of charges from the conductive support to the photosensitive layer during charging of the photosensitive layer having a laminated structure, and also causes the photosensitive layer to be integrally adhered and held to the conductive support. Acting as an adhesive layer,
Alternatively, in some cases, the conductive support exhibits the function of preventing reflection of light.

The binder resin used for the undercoat layer is polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, polyimide resin, chloride resin. Vinylidene resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol resin, water-soluble polyester resin, nitrocellulose, casein, gelatin,
Known materials such as polyglutamic acid, starch, starch acetate, amino starch, polyacrylic acid, polyacrylamide, zirconium chelate compounds, titanium chelate compounds, titanium alkoxide compounds, organic titanium compounds and silane coupling agents can be used. Further, the binder resin may contain a charge transporting substance, a charge transporting pigment and the like. The thickness of the undercoat layer is
0.01 to 10 μm is suitable, and preferably 0.05
Set in the range of ˜7 μm. Further, as the coating method used when the undercoat layer is provided, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used. Can be adopted.

The above-mentioned phthalocyanine crystal is preferably used as the charge generating material in the charge generating layer, but any known charge generating material such as bisazo pigment, phthalocyanine pigment, squarylium pigment, perylene pigment, dibromoanthanthrone and the like can be used. Can be used. The binder resin used for the charge generation layer can be selected from a wide range of insulating resins. Further, it can be selected from organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinylanthracene, polyvinylpyrene, and polysilane. Preferred binder resins include polyvinyl butyral resins, polyarylate resins (polycondensates of bisphenol A and phthalic acid, etc.), polycarbonate resins,
Insulation of polyester resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyamide resin, acrylic resin, polyacrylamide resin, polyvinyl pyridine resin, cellulose resin, urethane resin, epoxy resin, casein, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, etc. Examples of the resin include, but are not limited to: These binder resins may be used alone or in 2
A mixture of two or more species can be used.

The compounding ratio (weight ratio) of the charge generating material and the binder resin is preferably in the range of 10: 1 to 1:10. As a method for dispersing these, a usual method such as a ball mill dispersion method, an attritor dispersion method, a sand mill dispersion method, or the like can be used. Further, during this dispersion, it is effective that the particles have a particle size of 0.5 μm or less, preferably 0.3 μm or less, more preferably 0.15 μm or less. Further, as a solvent used for dispersing these, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran. Ordinary organic solvents such as methylene chloride, methylene chloride, chloroform, chlorobenzene, and toluene can be used, and these can be used alone or in admixture of two or more. Further, as a coating method used when the charge generating layer is provided, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used. Can be adopted.

In the electrophotographic photoreceptor of the present invention, the phthalocyanine crystal used in combination with the charge transport resin is a gallium phthalocyanine halide crystal disclosed in JP-A-5-98181.
JP-A-5-140472 and JP-A-5-140
No. 473, a halogenated tin phthalocyanine crystal, JP-A-5-263007 and JP-A-5-279591, hydroxygallium phthalocyanine crystals, JP-A-4-189873 and JP-A-5-43813. The oxytitanium phthalocyanine hydrate crystal disclosed in the publication can be mentioned, whereby an electrophotographic photoreceptor having particularly high sensitivity and excellent in repeated stability can be obtained.

As the chlorogallium phthalocyanine crystal used in the present invention, as disclosed in Japanese Patent Laid-Open No. 5-98181, a chlorogallium phthalocyanine crystal produced by a known method is used in an automatic mortar, a planetary mill, and a vibration. It can be produced by mechanically dry pulverizing with a mill, a CF mill, a roll mill, a sand mill, a kneader or the like, or by performing a wet pulverization treatment with a solvent using a ball mill, a mortar, a sand mill, a kneader or the like after dry pulverizing. As the solvent used in the above treatment, aromatics (toluene, chlorobenzene, etc.), amides (dimethylformamide, N-methylpyrrolidone, etc.), aliphatic alcohols (methanol, ethanol, butanol, etc.),
Aliphatic polyhydric alcohols (ethylene glycol, glycerin, polyethylene glycol, etc.), araliphatic alcohols (benzyl alcohol, phenethyl alcohol, etc.), esters (acetate ester, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, etc.) , Dimethyl sulfoxide, ethers (diethyl ether, tetrahydrofuran, etc.), a mixed system of several kinds, a mixed system of water and these organic solvents, and the like. The solvent used is 1 to 200 parts with respect to chlorogallium phthalocyanine,
It is preferably used in the range of 10 to 100 parts. The treatment temperature is 0 ° C to the boiling point of the solvent or less, preferably 10 to 60 ° C. Further, at the time of pulverization, a grinding aid such as salt and sodium nitrate can be used. Grinding aid is 0.5 to pigment
-20 times, preferably 1-10 times.

Crystals of dichlorotin phthalocyanine are disclosed in JP-A-5-140472 and JP-A-5-140473.
As disclosed in Japanese Patent Laid-Open Publication No. JP-A No. 2003-115, it can be obtained by pulverizing dichlorotin phthalocyanine crystals produced by a known method in the same manner as the above-mentioned chlorogallium phthalocyanine, and treating with a solvent. A hydroxygallium phthalocyanine crystal is disclosed in JP-A-5-263007 and JP-A-5-279591.
A chlorogallium phthalocyanine crystal produced by a known method is subjected to hydrolysis or acid pasting in an acid or alkaline solution to synthesize a hydroxygallium phthalocyanine crystal, and directly subjected to solvent treatment, or
Alternatively, the hydroxygallium phthalocyanine crystal obtained by synthesis is subjected to a wet milling treatment with a solvent using a ball mill, a mortar, a sand mill, a kneader or the like, or by performing a dry milling treatment without using a solvent and then performing a solvent treatment. It can be manufactured. As the solvent used in the above treatment, aromatics (toluene, chlorobenzene, etc.), amides (dimethylformamide, N-
Methylpyrrolidone, etc.), aliphatic alcohols (methanol, ethanol, butanol, etc.), aliphatic polyhydric alcohols (ethylene glycol, glycerin, polyethylene glycol, etc.), aromatic aliphatic alcohols (benzyl alcohol, phenethyl alcohol, etc.), esters Compounds (acetate, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, etc.), dimethylsulfoxide, ethers (diethyl ether, tetrahydrofuran, etc.), and several types of mixed systems, water and these organic solvents, etc. can give. The solvent used is 1 to 200 parts, preferably 10 to 200 parts with respect to hydroxygallium phthalocyanine.
Used in the range of 100 parts. The processing temperature is 0 to 150 ° C,
It is preferably performed at room temperature to 100 ° C. Further, at the time of pulverization, a grinding aid such as salt and sodium nitrate can be used.
The grinding aid is 0.5 to 20 times the amount of the pigment, preferably 1 to
Use 10 times.

The oxytitanium phthalocyanine crystal is
JP-A-4-189873 and JP-A-5-438
As disclosed in Japanese Patent No. 13, the oxytitanium phthalocyanine produced by a known method is acid pasted, or salt milled with an inorganic salt using a ball mill, a mortar, a sand mill, a kneader or the like. , Oxytitanium phthalocyanine crystal having a relatively low crystallinity, which has a peak at 27.2 ° in X-ray diffraction spectrum, is directly subjected to solvent treatment, or together with the solvent, ball mill, mortar, sand mill, kneader, etc. It can be manufactured by carrying out a wet pulverization process. As the acid used for acid pasting, sulfuric acid is preferable, and the one having a concentration of 70 to 100%, preferably 95 to 100% is used, and the dissolution temperature is
It is set in the range of -20 to 100 ° C, preferably 0 to 60 ° C. The amount of concentrated sulfuric acid is 1 to 100 times, preferably 3 to 100 times the weight of the oxytitanium phthalocyanine crystal.
It is set to a range of 50 times. As the solvent to be deposited,
Water or a mixed solvent of water and an organic solvent is used in an arbitrary amount, and a mixed solvent of water and an alcohol-based solvent such as methanol or ethanol, or a mixed solvent of water and an aromatic-based solvent such as benzene or toluene. Solvents are particularly preferred. There is no particular limitation on the temperature for precipitation, but in order to prevent heat generation,
It is preferable to cool with ice or the like. Further, the ratio of the oxytitanium phthalocyanine crystal and the inorganic salt is 1 by weight.
/0.1 to 1/20, and the range of 1 / 0.5 to 1/5 is preferable.

As the solvent used in the above solvent treatment, aromatics (toluene, chlorobenzene, etc.), aliphatic alcohols (methanol, ethanol, butanol, etc.), halogenated hydrocarbons (dichloromethane, chloroform, trichloroethane, etc.) ), And several kinds of mixed systems, a mixed solvent of water and these organic solvents, and the like. The solvent is used in a range of 1 to 100 times, preferably 5 to 50 times, that of oxytitanium phthalocyanine. The treatment temperature is from room temperature to 100 ° C., preferably 50 to 1
Set in the range of 00 ° C. Grinding aid is 0.5 to pigment
-20 times, preferably 1-10 times. In the electrophotographic photoreceptor, these phthalocyanine compound crystals are preferably contained in the charge generation layer in the photosensitive layer as a charge generation material.

In the electrophotographic photoreceptor of the present invention, when the surface layer is used as the charge transport layer, (a) the purified charge transport resin is used alone or in combination of two or more kinds,
(B) The purified charge transporting resin is used as a mixture with a low molecular weight charge transporting material such as a hydrazone charge transporting material, a triarylamine charge transporting material, or a stilbene charge transporting material. You can use it. The compounding ratio (weight ratio) can be set arbitrarily in any case, but care must be taken to reduce the charge transport property and the film strength. The thickness of the charge transport layer is appropriately 5 to 50 μm, preferably 10 to 35 μm. Further, as a coating method used when providing the charge transport layer, a blade coating method, a Mayer bar coating method,
Conventional methods such as a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used. Examples of the solvent used for coating include commonly used organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene, and these can be used alone or in combination of two or more.

In the electrophotographic photoreceptor of the present invention, when the surface layer is used as an overcoat layer, a known binder resin, hydrazone type charge transport material, triarylamine type charge transport material, stilbene type charge transport material or the like is used. An overcoat layer having the above composition (a) or (b) may be formed on the charge transport layer formed as described above or the charge generation layer formed by dispersing a pigment in a known binder resin. The thickness of the overcoat layer is appropriately 1 to 20 μm,
It is preferably in the range of 2 to 10 μm. Further, as a coating method used when providing the charge transport layer, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method is used. Can be used. As the solvent, commonly used organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene can be used alone or in combination of two or more kinds, but a solvent in which the lower layer is difficult to dissolve is used as much as possible. Is preferred.

In the electrophotographic photoreceptor of the present invention, when the surface layer is used as a photoreceptor having a single-layer structure, the composition of (a) or (b) is further added with an anthanthrone pigment, an azo pigment, a perylene pigment, a phthalocyanine pigment, etc. In addition to the known charge generating material, it is used. The ratio of other material: charge generating material is other material: charge generating material = 99: 1 to
It is used in the range of 50:50, preferably in the range of 95: 5 to 60:40. The film thickness is suitably 5 to 50 μm, preferably 10 to 40 μm. Further, as the coating method used for the photoreceptor of this single-layer structure, a usual method such as a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used. Can be used. Examples of the solvent used for coating include commonly used organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene, and these can be used alone or in combination of two or more.

The electrophotographic photosensitive member of the present invention includes, in addition to a conventional electrophotographic apparatus using a corona discharge type charging member,
It also exhibits excellent characteristics when using the contact charging method. Next, an electrophotographic apparatus using the electrophotographic photosensitive member of the present invention will be described. FIG. 8 is a schematic configuration diagram of the electrophotographic apparatus of the present invention. Reference numeral 10 denotes a photoconductor, which is provided with a contact charging type contact charging member 11. A voltage is supplied from a power supply 12 to the charging member 11. An exposure device 13 and a developing device 1 are provided around the photoconductor.
4, a transfer device 15, a cleaning device 16, and a static eliminator 17 are provided. Reference numeral 18 denotes a fixing device.

The contact charging member is arranged so as to be in contact with the surface of the photoconductor, and a voltage is directly and uniformly applied to the photoconductor to charge the photoconductor to a predetermined potential. This contact charging member includes metals such as aluminum, iron and copper, conductive polymer materials such as polyacetylene, polypyrrole and polythiophene, polyurethane rubber, silicone rubber, epichlorohydrin rubber, ethylene propylene rubber, acrylic rubber, fluororubber. An elastomer material such as styrene-butadiene rubber or butadiene rubber in which conductive fine particles such as carbon black, copper iodide, silver iodide, zinc sulfide, silicon carbide or metal oxide are dispersed can be used. Examples of metal oxides include ZnO,
Examples thereof include SnO ₂ , TiO ₂ , In ₂ O ₃ , MnO ₃ , and complex oxides thereof. In addition, a conductivity may be imparted by including a perchlorate in the elastomer material. Furthermore, a coating layer can be provided on the surface. Materials for forming this coating layer include N-alkoxymethylated nylon, cellulose resin, vinyl pyridine resin, phenol resin, polyurethane, polyvinyl butyral,
Melamine resin and the like are used alone or in combination.
It is also possible to use an emulsion resin material, for example, an acrylic resin emulsion, a polyester resin emulsion, polyurethane, particularly an emulsion resin synthesized by soap-free emulsion polymerization. Conductive agent particles may be dispersed in these resins in order to further adjust the resistivity, or an antioxidant may be contained in order to prevent deterioration. Further, the emulsion resin may contain a leveling agent or a surfactant in order to improve film-forming properties when forming the coating layer.

The shape of the contact charging member may be a roller type, a blade type, a belt type, a brush type, or the like. Further, the resistance of the contact charging member is preferably 10 ⁰ to 10 ¹⁴ Ωcm, more preferably 10
It is in the range of ² to 10 ¹² Ωcm. The voltage applied to the contact charging member may be DC or AC. It is also possible to apply in the form of direct current + alternating current.

[0056]

EXAMPLES The present invention will be described below with reference to examples. In addition, "part" means "part by weight". Synthesis Example 1 [Synthesis of Charge Transport Resin [Exemplified Compound (6)]] N, N-bis [3- (2-ethoxycarbonylethyl)]
Phenyl] -3,4-xylidine (the structure of the A portion is shown by 3 and the terminal is a diethyl ester) 8.0 g, ethylene glycol 20.0 g and tetrabutoxy titanium 0.
1 g was heated under reflux for 3 hours under a nitrogen stream, then 0.5
The pressure was reduced to mmHg and the temperature was raised to 230 ° C. while distilling off ethylene glycol, and the reaction was continued for 3 hours. Then THF
, The insoluble matter is filtered, and the filtrate is dropped into 1000 ml of water to precipitate a polymer. The obtained polymer was washed with water and dried to obtain 7.2 g of a charge transporting resin [Exemplified compound (6)]. About the obtained resin GPC
When the measurement was carried out, the molecular weight of the main product was Mw = 1.0.
5 × 10 ⁵ (in terms of styrene) (degree of polymerization p = about 230), and Mw = 2.79 × 10 ³ , 1.
35 × 10 ³ and 9.12 × 10 ² (styrene equivalent)
0.9, 0.5 and 2.0 (Area%) respectively
Was detected.

Synthesis Example 2 [Synthesis of Charge Transport Resin [Exemplified Compound (1)]] N, N′-diphenyl-N, N′-bis [3- (2-ethoxycarbonylethyl) phenyl]-[1, 1'-biphenyl] -4,4'-diamine (the structure of the A part is shown by 6 and the terminal is a diethyl ester) 10.0 g, ethylene glycol 20.0 g and tetrabutoxy titanium 0.1 g were added under nitrogen flow to 3 Heat to reflux for hours, then
The pressure was reduced to 0.5 mmHg and the temperature was raised to 230 ° C. while distilling off ethylene glycol, and the reaction was continued for 3 hours. After that, it was dissolved in 100 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1000 ml of acetone to precipitate a polymer. The obtained polymer was dissolved in 100 ml of THF, the filtrate was dropped into 1000 ml of water to precipitate the polymer, and the polymer was washed with water to obtain 8.4 g of a charge transporting resin [exemplified compound (1)]. About the obtained resin GPC
Upon measurement, the molecular weight of the main product was Mw = 1.1.
0 × 10 ⁵ (in terms of styrene) (polymerization degree p = about 165), and Mw = 2.67 × 10 ³ , 1.
99 × 10 ³ and 1.32 × 10 ³ (styrene equivalent)
0.6, 0.6 and 1.7 (Area%) respectively
Was detected.

Synthesis Example 3 [Synthesis of Charge Transporting Resin [Exemplified Compound (23)]] N, N'-diphenyl-N, N'-bis [3- (2-ethoxycarbonylethyl) phenyl]-[1, 1'-biphenyl] -4,4'-diamine 10.0 g, ethylene glycol 20.0 g and tetrabutoxy titanium 0.
1 g was heated under reflux for 3 hours under a nitrogen stream, then 0.5
The pressure was reduced to mmHg to distill off ethylene glycol. Then, it was dissolved in 200 ml of methylene chloride, a solution of 3.0 g of isophthalic acid dichloride in 100 ml of methylene chloride was added dropwise, and the mixture was heated under reflux in the presence of 6.1 g of triethylamine for 30 minutes. After adding 3 ml of methanol and heating under reflux for another 30 minutes, the insoluble matter is filtered, the filtrate is dropped into 1000 ml of ethanol to precipitate a polymer, which is washed with ethanol and dried to obtain a charge transporting resin [exemplified compound]. (23)] 6.1 g was obtained. GPC measurement of the obtained resin revealed that the main product had a molecular weight of Mw = 1.70 × 10 ⁴ (in terms of styrene) (degree of polymerization p ′ = about 20), and Mw = 5 as a by-product. .1
0x10 ³ , 2.55x10 ³ and 1.70x10 ³
(Styrene equivalent) 0.5, 0.7 and 1.
8 (Area%) was detected.

Synthesis Example 4 [Synthesis of Charge Transport Resin [Exemplified Compound (3)]] N,
10.0 g of N'-diphenyl-N, N'-bis [3- (2-ethoxycarbonylethyl) phenyl]-[1,1'-biphenyl] -4,4'-diamine, 1,4-cyclohexanediol ( Cis-trans mixture) 20.0
g and 0.1 g of tetrabutoxytitanium were heated under reflux for 3 hours under a nitrogen stream, and then the pressure was reduced to 0.5 mmHg to distill 1,4-cyclohexanediol and to remove 230 g.
The mixture was heated to ° C and the reaction was continued for 5 hours. Then, it was dissolved in 100 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1000 ml of ethanol to precipitate a polymer. The obtained polymer is washed with ethanol and water, dried,
8.6 g of a charge transporting resin [exemplary compound (3)] was obtained.
GPC measurement of the obtained resin revealed that the molecular weight of the main product was Mw = 8.20 × 10 ⁴ (styrene conversion) (degree of polymerization p = about 35). In addition, as by-products, Mw = 9.37 × 10 ³ , 7.05 × 10 ³ and 4.70 × 10 ³ (styrene conversion), respectively.
6, 0.7 and 2.1 (Area%) were detected.

Synthesis Example 5 [Synthesis of Charge Transport Resin [Exemplified Compound (5)]] N,
N'-diphenyl-N, N'-bis [3- (2-ethoxycarbonylethyl) phenyl]-[1,1'-biphenyl] -4,4'-diamine 10.0 g, 1,4-cyclohexanedimethanol (Cis-trans mixture) 2
0.0 g and 0.1 g of tetrabutoxytitanium are heated and refluxed under a nitrogen stream for 2 hours, then decompressed to 0.5 mmHg and heated to 230 ° C. while distilling off 1,4-cyclohexanedimethanol and heated for 4 hours. The reaction continued. Then, it was dissolved in 100 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1000 ml of ethanol to precipitate a polymer. The obtained polymer is washed with ethanol and water,
After drying, the charge transporting resin [Exemplified compound (5)] 8.0
g was obtained. GPC measurement of the obtained resin revealed that the molecular weight of the main product was Mw = 2.40 × 10 ⁴ (styrene conversion) (degree of polymerization p = about 30). Also, as a by-product, Mw = 4.80 × 10 ³ , 3.20 × 1
0.7, 0.9, and 1.8 (Area%) were detected at 0 ³ and 1.62 × 10 ³ (styrene conversion), respectively.

Synthesis Example 6 [Synthesis of Charge Transporting Resin [Exemplified Compound (7)]] 3,3'-Dimethyl-N, N'-bis (3,4-dimethylphenyl) -N, N'-bis [ 2- (2-methoxycarbonylethyl) phenyl]-[1,1′-biphenyl] -4,4′-diamine (the structure of the A part is shown by 19, the terminal is dimethyl ester) 20.0 g, ethylene glycol 40 0.0 g and tetrabutoxy titanium 0.1
g under reflux for 3 hours under nitrogen flow, then 0.5 m
While reducing the pressure to mHg and distilling off ethylene glycol, 2
It was heated to 30 ° C. and the reaction was continued for 3 hours. After that, it was dissolved in 200 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1500 ml of ethanol to precipitate a polymer. The obtained polymer was washed with ethanol and dried to obtain 19.2 g of a charge transporting resin [Exemplified compound (7)]. When GPC measurement was performed on the obtained resin, the molecular weight of the main product was Mw = 1.21 × 10 ⁵ (in terms of styrene) (degree of polymerization p = about 165). As by-products, Mw = 3.64 × 10 ³ , 2.18 × 10 ³ and 1.46 × 10 ³ (styrene conversion), respectively.
0, 0.5 and 1.2 (Area%) were detected.

Synthesis Example 7 [Synthesis of Charge Transporting Resin [Exemplified Compound (12)]] N, N-bis [4- (4-ethoxycarbonylmethylphenyl) phenyl] -3,4-xylidine (Structure of A Part) Is 46 and the end is diethyl ester) 10.0
g, 20.0 g of ethylene glycol and 0.1 g of tetrabutoxytitanium were heated under reflux for 2 hours under a nitrogen stream, then decompressed to 0.5 mmHg and heated to 230 ° C. while distilling off ethylene glycol and reacted for 5 hours. Continued.
Then, it was dissolved in 100 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1000 ml of ethanol to precipitate a polymer. The obtained polymer is washed with ethanol and dried to obtain a charge transporting resin [Exemplified compound (12)].
8.1 g was obtained. GPC measurement of the obtained resin revealed that the molecular weight of the main product was Mw = 1.21 × 10.
⁵ (in terms of styrene) (degree of polymerization p = about 210), and Mw = 3.44 × 10 ³ , 1.75 × 1 as a by-product.
1.1, 1.1 and 0.4 (Area%) were detected in 0 ³ and 1.14 × 10 ³ (styrene conversion), respectively.

Synthesis Example 8 [Synthesis of Charge Transporting Resin [Exemplified Compound (13)]] N, N'-diphenyl-N, N'-bis [4- (4-ethoxycarbonylmethylphenyl) phenyl]-[1 ，
1'-biphenyl] -4,4'-diamine (the structure of A part is shown by 47 and the terminal is diethyl ester) 10.0
g, 20.0 g of ethylene glycol and 0.1 g of tetrabutoxytitanium are heated under reflux for 3 hours under a nitrogen stream, then depressurized to 0.5 mmHg and heated to 230 ° C. while distilling off ethylene glycol and reacted for 3 hours Continued.
Then, it was dissolved in 100 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1000 ml of ethanol to precipitate a polymer. The obtained polymer was washed with ethanol and dried to obtain a charge transporting resin [Exemplified compound (13)].
8.0 g was obtained. When GPC measurement was performed on the obtained resin, the molecular weight of the main product was Mw = 1.06 × 10.
⁵ (in terms of styrene) (degree of polymerization p = about 140).
As a by-product, Mw = 6.06 × 10 ³ , 3.
00 × 10 ³ and 1.52 × 10 ³ (styrene equivalent)
0.7, 0.8 and 0.9 (Area%) respectively
Was detected.

Synthesis Example 9 [Synthesis of Charge Transport Resin [Exemplified Compound (14)]] N, N′-diphenyl-N, N′-bis [4- (4-ethoxycarbonylethylphenyl) phenyl]-[1 ，
1'-biphenyl] -4,4'-diamine (the structure of the A portion is shown by 48 and the terminal is a diethyl ester) 10.0
g, 20.0 g of ethylene glycol and 0.1 g of tetrabutoxytitanium are heated under reflux for 3 hours under a nitrogen stream, then depressurized to 0.5 mmHg and heated to 230 ° C. while distilling off ethylene glycol and reacted for 3 hours. Continued.
Then, it was dissolved in 100 ml of methylene chloride, the insoluble matter was filtered off, and the filtrate was dropped into 1000 ml of ethanol to precipitate a polymer. The obtained polymer is washed with ethanol and dried to obtain a charge transporting resin [Exemplified compound (14)].
8.6 g were obtained. When GPC measurement was performed on the obtained resin, the molecular weight of the main product was Mw = 1.19 × 10.
⁴ (in terms of styrene) (degree of polymerization p = about 150).
As a by-product, Mw = 4.76 × 10 ³ , 2.
35 × 10 ³ and 1.59 × 10 ² (converted to styrene)
1.2, 1.0 and 1.6 (Area%) respectively
Was detected.

Synthesis Example 10 [Synthesis of Charge Transporting Resin [Exemplified Compound (28)]] N, N′-diphenyl-N, N′-bis [4- (4-ethoxycarbonylethylphenyl) phenyl]-[1 ，
1'-biphenyl] -4,4'-diamine (the structure of the A portion is shown by 48 and the terminal is a diethyl ester) 10.0
g, 20.0 g of ethylene glycol and 0.1 g of tetrabutoxytitanium were heated under reflux for 3 hours under a nitrogen stream.
Then, the pressure was reduced to 0.5 mmHg, ethylene glycol was distilled off, and the residue was dissolved in 100 ml of methylene chloride. Next, 2.4 g of isophthalic acid chloride was added to 10 ml of methylene chloride.
The solution dissolved in was added and heated under reflux for 30 minutes, further 3 ml of methanol was added and heated under reflux for 30 minutes, insoluble matter was filtered, and the filtrate was dropped into 1000 ml of ethanol to precipitate a polymer. The obtained polymer is washed with ethanol and dried to obtain a charge transporting resin [exemplified compound (2
8)] 9.5 g was obtained. When GPC measurement was performed on the obtained resin, the molecular weight of the main product was Mw = 1.33.
It was x10 ⁴ (in terms of styrene) (degree of polymerization p '= about 15). Further, as a by-product, Mw = 7.10 × 1
0 ³ , 3.55 × 10 ³ and 1.77 × 10 ³ (styrene conversion), 1.1, 1.1 and 1.8 (A
rea%) was detected.

Synthesis Example 11 [Synthesis of Charge Transporting Resin [Exemplified Compound (30)]] N, N'-diphenyl-N, N'-bis (3-hydroxyphenyl)-[1,1'-biphenyl]- 4,4'-
Diamine (see U.S. Pat. No. 4,806,443) 10.0 g, 100 ml dry tetrahydrofuran and 8 ml triethylamine while stirring under a stream of argon gas ethylene glycol bischloroformate 34.20 in 20 ml dry tetrahydrofuran. 5 g was added dropwise, 5 ml of dry tetrahydrofuran containing 0.1 g of phenol was added, and the mixture was stirred for 5 minutes and then filtered to remove triethylamine hydrochloride. The filtrate was added dropwise to methanol to precipitate the polymer, which was filtered,
Dry and charge transport resin [Exemplified compound (30)] 9.
1 g was obtained. GPC measurement of the obtained resin revealed that the molecular weight of the main product was Mw = 1.8 × 10 ⁵ (in terms of styrene) (degree of polymerization p ″ = about 260). Mw = 4.18 × 10 ³ , 2.0
2.2, 1.4 and 2.4 (Area%) were detected at 5 × 10 ³ and 1.37 × 10 ³ (styrene equivalent), respectively.

Synthetic Example 12 30 parts of 1,3-diiminoisoindoline and 9.1 parts of gallium trichloride were put in 230 parts of quinoline and reacted at 200 ° C. for 3 hours, and then the product was filtered and acetone was added. ,
After washing with methanol and then drying the wet cake,
28 parts of chlorogallium phthalocyanine crystals were obtained. After 15 parts of the obtained chlorogallium phthalocyanine crystal was dry-ground for 3 hours in an automatic mortar (Lab-Mill UT-21 type, manufactured by Yamato Scientific Co., Ltd.), glass beads (1 mm
φ) 300 parts with benzyl alcohol 500 at room temperature
After milling for 24 hours in the chamber, the glass beads were separated by filtration, washed with methanol and dried, and powder X-ray diffraction spectrum showed 2θ ± 0.2 ° = 7.4 °, 16.6 °, 2 °.
A chlorogallium phthalocyanine crystal having strong diffraction peaks at 5.5 ° and 28.3 ° was obtained. This is CG-1
And

Synthesis Example 13 50 g of phthalonitrile and 27 g of anhydrous stannic chloride
Was added to 350 ml of 1-chloronaphthalene, and 195
After reacting at ℃ for 5 hours, the product was filtered and
After washing with chlornaphthalene, acetone, methanol and then water, the crystals were dried under reduced pressure to obtain 18.3 g of dichlorotin phthalocyanine crystals. 5 g of the obtained dichlorotin phthalocyanine crystal was mixed with 10 g of salt and agate ball (20 g).
(mmφ) 500g and put in an agate pot, 400r with a planetary ball mill (P-5 type, Fritsch)
After crushing with pm for 10 hours, it was thoroughly washed with water and dried.
This is THF 150g, glass beads (1mmφ) 20
After milling with 0 g for 24 hours at room temperature, the glass beads were separated by filtration, washed with methanol and dried to obtain a powder X-ray diffraction spectrum of 2θ ± 0.2 ° = 8.5 °, 1
Dichlorotin phthalocyanine crystals having strong diffraction peaks at 1.2 °, 14.5 ° and 27.2 ° were obtained. This is designated as CG-2.

Synthesis Example 14 15 parts of the chlorogallium phthalocyanine crystal obtained in Synthesis Example 12 was dissolved in 300 parts of concentrated sulfuric acid at 0 ° C. and then 5 ° C.
The above solution was added dropwise to 2000 parts of distilled water to reprecipitate crystals. After washing with distilled water, diluted ammonia water, etc., it was dried to obtain 12.5 parts of hydroxygallium phthalocyanine crystals. The crystals were crushed in an automatic mortar for 5.5 hours, milled with 60 parts of dimethylformamide and 120 parts of glass beads having a diameter of 1 mm for 24 hours, separated, washed with methanol and dried to obtain a powder X-ray diffraction spectrum. At 2θ ± 0.2 ° = 7.5 °, 9.9 °, 12.5
°, 16.3 °, 18.6 °, 25.1 ° and 28.3
A hydroxygallium phthalocyanine crystal having a strong diffraction peak at ° was obtained. This is designated as CG-3.

Synthesis Example 15 30 parts of 1,3-diiminoisoindoline and 17 parts of titanium tetrabutoxide were placed in 200 parts of 1-chlornaphthalene, and the reaction was carried out at 190 ° C. for 5 hours under a nitrogen stream, and then the product was filtered. Separately, it was washed with aqueous ammonia, water, and acetone to obtain 40 parts of oxytitanium phthalocyanine. Obtained oxytitanium phthalocyanine crystal 10
Parts and 20 parts sodium chloride in an automatic mortar (Lab-Mil
1 UT-21 type, manufactured by Yamato Scientific Co., Ltd.) for 3 hours. Then, it was thoroughly washed with distilled water and dried to obtain 9.6 parts of oxytitanium phthalocyanine crystal. The obtained oxytitanium phthalocyanine crystal had a clear peak at 2θ ± 0.2 ° = 27.3 ° in the powder X-ray diffraction spectrum. The obtained oxytitanium phthalocyanine crystal was stirred in a mixed solvent of 40 parts of distilled water and 4 parts of monochlorobenzene at 50 ° C. for 1 hour, filtered, thoroughly washed with methanol, and dried to obtain a powder X-ray diffraction spectrum. Thus, an oxytitanium phthalocyanine hydrate crystal having a strong diffraction peak at 2θ ± 0.2 ° = 27.3 ° was obtained. This is designated as CG-4.

Example 1 5.0 g of the charge transporting resin [exemplary compound (6)] obtained in Synthesis Example 1 was dissolved in 100 ml of tetrahydrofuran, and 20 ml of distilled water was added to the resin solution while stirring. Dropped. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.6 g of a purified resin.
When GPC measurement was performed on the obtained resin, it was found that the by-products had peaks of Mw = 2.79 × 10 ³ , 1.35 × 10 ³ and 9.12 × 10 ² (styrene conversion), respectively. 1 or less, 0.5 or less and 0.2 (Area
%). On the other hand, 30 mmφ that has been subjected to honing
Zirconium compound (trade name: Organix ZC540, manufactured by Matsumoto Pharmaceutical Co., Ltd.) on the aluminum cylindrical substrate of
A solution consisting of 100 parts and 10 parts of a silane compound (trade name: A1110, manufactured by Nippon Unicar Co., Ltd.), 400 parts of i-propanol and 200 parts of butanol was applied by a dip coating method, followed by heating and drying at 150 ° C. for 10 minutes to form a film. An undercoat layer having a thickness of 0.5 μm was formed. 10 parts of CG-1 were mixed with 10 parts of polyvinyl butyral resin (trade name: S-REC BM-S, manufactured by Sekisui Chemical Co., Ltd.) and 500 parts of n-butyl acetate, and treated with glass beads for 1 hour on a paint shaker to disperse. After that, the obtained coating solution is applied onto the above-mentioned undercoat layer by a dip coating method,
It was dried by heating at 0 ° C. for 10 minutes. Next, 5 parts of the purified charge transporting resin [Exemplified Compound (6)] was dissolved in 30 parts of monochlorobenzene, and the obtained coating solution was applied onto an aluminum cylindrical substrate having a charge generation layer by dip coating method. And heat dry at 120 ° C for 1 hour,
A charge transport layer having a film thickness of 15 μm was formed. The electrophotographic characteristics of the electrophotographic photosensitive member thus obtained are printed with a laser beam printer (XP-15 remodeling machine, manufactured by Fuji Xerox Co., Ltd.) in an environment of normal temperature and normal humidity (20 ° C., 40% RH). A test was conducted to evaluate the image quality after copying 10,000 sheets. The results are shown in Table 15.

Example 2 5.0 g of the charge transporting resin [exemplary compound (1)] obtained in Synthesis Example 2 was dissolved in 100 ml of tetrahydrofuran, and 20 ml of distilled water was added to the resin solution while stirring. Dropped. The precipitated resin was separated by filtration, washed sufficiently with water and then dried to obtain 4.4 g of a purified resin.
GPC measurement of the obtained resin revealed that the by-products had peaks of Mw = 2.67 × 10 ³ , 1.99 × 10 ³ and 1.32 × 10 ³ (styrene conversion), respectively. 1, 0.1 or less and 0.1 (Area%)
Decreased to. An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 by combining the charge generating materials with each other as shown in Table 15. The results are shown in Table 15.

Example 3 The charge-transporting resin obtained in Synthesis Example 3 [exemplified compound (2
3)] 5.0 g was dissolved in 100 ml of tetrahydrofuran, and the obtained resin solution was stirred and distilled water 2
0 ml was added dropwise. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.5 g of purified resin. GPC measurement of the obtained resin revealed that the by-products had peaks of Mw = 5.10 × 10 ³ , 2.55 × 10 ³ and 1.70 × 10 ³ (styrene equivalent), respectively. 1 or less, 0.1 or less, and 0.3 (Area
%). Table 1 shows combinations with charge generation materials.
An electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 as shown in 5. The results are shown in Table 15.

Example 4 5.0 g of the charge transporting resin [exemplary compound (3)] obtained in Synthesis Example 4 was dissolved in 100 ml of tetrahydrofuran, and 20 ml of distilled water was added to the resin solution while stirring. Dropped. The precipitated resin was separated by filtration, washed sufficiently with water and then dried to obtain 4.7 g of a purified resin.
When GPC measurement was performed on the obtained resin, the by-products had peaks of Mw = 9.37 × 10 ³ , 7.05 × 10 ³ and 4.70 × 10 ³ (in terms of styrene) of 0. 2, 0.1 and 0.4 (Area%). An electrophotographic photosensitive member was produced in the same manner as in Example 1, except that the combination with the charge generating material was as shown in Table 15.
evaluated. The results are shown in Table 15.

Example 5 5.0 g of the charge transporting resin [exemplary compound (5)] obtained in Synthesis Example 5 was dissolved in 100 ml of tetrahydrofuran, and 20 ml of distilled water was added to the resin solution while stirring. Dropped. The precipitated resin was separated by filtration, washed sufficiently with water, and dried to obtain 4.8 g of purified resin.
When GPC measurement was performed on the obtained resin, it was found that the by-products had peaks of Mw = 4.80 × 10 ³ , 3.20 × 10 ³ and 1.62 × 10 ³ (styrene conversion), respectively. 2, 0.2 and 0.2 (Area%). An electrophotographic photosensitive member was produced in the same manner as in Example 1, except that the combination with the charge generating material was as shown in Table 15.
evaluated. The results are shown in Table 15.

Example 6 5.0 g of the charge transporting resin [exemplary compound (7)] obtained in Synthesis Example 6 was dissolved in 100 ml of tetrahydrofuran, and 20 ml of distilled water was added to the resin solution while stirring. Dropped. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.3 g of a purified resin.
GPC measurement of the obtained resin revealed that the by-products had peaks of Mw = 3.64 × 10 ³ , 2.18 × 10 ³ and 1.46 × 10 ³ (in terms of styrene) of 0. 1 or less, 0.1 or less and 0.1 or less (Ar
ea%). Combination with charge generation material,
Electrophotographic photoreceptors were prepared and evaluated in the same manner as in Example 1 as shown in Table 15. The results are shown in Table 15.

Example 7 The charge-transporting resin obtained in Synthesis Example 7 [Exemplified Compound (1
2)] 5.0 g was dissolved in 100 ml of tetrahydrofuran, and the resulting resin solution was stirred and distilled water 2
0 ml was added dropwise. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.5 g of purified resin. When GPC measurement was performed on the obtained resin, it was found that the by-products had peaks of Mw = 3.44 × 10 ³ , 1.75 × 10 ³ and 1.14 × 10 ³ (styrene conversion), respectively. 1 or less, 0.2 and 0.1 or less (Area
%). Table 1 shows combinations with charge generation materials.
An electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 as shown in 5. The results are shown in Table 15.

Example 8 The charge transporting resin obtained in Synthesis Example 8 [exemplary compound (1
3)] 5.0 g is dissolved in 100 ml of dichloromethane,
While stirring the obtained resin solution, 20 m of distilled water
1 was added dropwise. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.5 g of purified resin. GPC measurement of the obtained resin revealed that the by-products had peaks at Mw = 6.06 × 10 ³ , 3.00 × 10 ³ and 1.52 × 10 ³ (converted to styrene) of 0. 1 or less, 0.1 or less, and 0.1 or less (Area
%). Table 1 shows combinations with charge generation materials.
An electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 as shown in 5. The results are shown in Table 15.

Examples 9 to 12 The charge transporting resin obtained in Synthesis Example 9 [Exemplified Compound (1
4)] 5.0 g is dissolved in 100 ml of dichloromethane,
While stirring the obtained resin solution, 20 m of distilled water
1 was added dropwise. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.5 g of purified resin. When GPC measurement was performed on the obtained resin, it was found that the by-products had peaks of Mw = 4.76 × 10 ³ , 2.35 × 10 ³ and 1.59 × 10 ² (in terms of styrene) of 0. It decreased to 2, 0.1 or less and 0.4 (Area%). An electrophotographic photosensitive member was produced in the same manner as in Example 1, except that the combination with the charge generating material was as shown in Table 15.
Each was evaluated. The results are shown in Table 15.

Examples 13 to 16 The charge transporting resin obtained in Synthesis Example 10 [Exemplified Compound (2
8)] 5.0 g is dissolved in 100 ml of dichloromethane,
While stirring the obtained resin solution, 20 m of distilled water
1 was added dropwise. The precipitated resin was separated by filtration, washed sufficiently with water and then dried to obtain 4.7 g of a purified resin. GPC measurement of the obtained resin revealed that the by-products had peaks of Mw = 7.10 × 10 ³ , 3.55 × 10 ³ and 1.77 × 10 ³ (converted to styrene) of 0. It was reduced to less than 1, 0.1 and 0.3 (Area%). An electrophotographic photosensitive member was produced in the same manner as in Example 1, except that the combination with the charge generating material was as shown in Table 15.
Each was evaluated. The results are shown in Table 15.

Examples 17 to 20 The charge-transporting resin obtained in Synthesis Example 11 [Exemplified Compound (3
0)] 5.0 g was dissolved in 100 ml of tetrahydrofuran, and the resulting resin solution was stirred and distilled water 2
0 ml was added dropwise. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.5 g of purified resin. GPC measurement of the obtained resin revealed that the by-products had peaks of Mw = 4.18 × 10 ³ , 2.05 × 10 ³ and 1.37 × 10 ³ (converted to styrene), respectively. 2, 0.1 and 0.4 (Area%). An electrophotographic photosensitive member was produced in the same manner as in Example 1 by combining the charge generating materials with each other as shown in Table 15, and evaluated for each. The results are shown in Table 15.

Example 21 An electrophotographic photosensitive member was prepared in the same manner as in Example 1, and a printer for personal computer (trade name: PR100) was used.
0, made by NEC Corporation, at room temperature and normal humidity (20 ° C, 40 ° C)
% RH) environment, 10,000 sheets printing durability test,
Image evaluation was performed. 5mmφ as the charging member at this time
A 18.8 stainless steel shaft having an elastic layer and a resin layer formed on the outer periphery thereof was used. That is, an elastic layer made of polyether polyurethane rubber, which is made elastic by adding 0.5% of lithium perchlorate to the outer periphery of the shaft,
Formed to have a diameter of 5 mm, and 0.001% on the surface.
The coating liquid consisting of the polyester-based polyurethane emulsion resin solution to which the methylphenyl silicone leveling agent was added is applied by a dip coating method and dried at 120 ° C. for 20 minutes to obtain a roll type charging member having a coating layer with a thickness of 20 μm. Using. The results are shown in Table 15.

Comparative Examples 1 to 20 Electrophotographic photoreceptors were prepared and evaluated in the same manner as in Examples 1 to 20 except that the charge transporting resin was not purified. The results are shown in Table 16. Comparative Example 21 An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 21, except that the charge transporting resin was not purified. Table 16 shows the results.

Comparative Example 22 5.0 g of the charge-transporting resin [exemplary compound (6)] obtained in Synthesis Example 1 was dissolved in 100 ml of tetrahydrofuran, and the obtained resin solution was added dropwise to 100 ml of distilled water while stirring. did. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.6 g of a purified resin. When GPC measurement was performed on the obtained resin, it was found that the by-products had peaks of Mw = 2.79 × 10 ³ , 1.35 × 10 ³ and 9.12 × 10 ² (styrene conversion), respectively. It was 9, 0.5 and 2.0 (Area%), and there was no effect of removing impurities.

Comparative Example 23 The charge transporting resin obtained in Synthesis Example 11 [exemplified compound (3
0)] 5.0 g was dissolved in 100 ml of tetrahydrofuran, and the obtained resin solution was added dropwise to 20 ml of ethanol while stirring. The precipitated resin was separated by filtration, washed thoroughly with water and then dried to obtain 4.5 g of purified resin. GPC measurement of the obtained resin revealed that the by-products had peaks of Mw = 4.18 × 10 ³ , 2.05 × 10 ³ and 1.37 × 10 ³ (converted to styrene) of 2. It was 2, 1.4 and 2.4 (Area%), and there was no effect of removing impurities.

[0086]

[Table 15]

[0087]

[Table 16]

[0088]

EFFECT OF THE INVENTION The purified charge transporting resin obtained by the purification method of the present invention is, compared with the case where it is purified by the conventional reprecipitation method, as is clear from the comparison results of the above Examples and Comparative Examples. And shows an excellent effect of removing impurities. The electrophotographic photosensitive member produced by using the charge transporting resin purified by the present invention has excellent printing durability and very high stability, and an electrophotographic apparatus using the
It is possible to obtain a copy having excellent image quality for a long period of time.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an example of an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic sectional view of an example of the electrophotographic photosensitive member of the present invention.

FIG. 3 is a schematic sectional view of an example of the electrophotographic photosensitive member of the present invention.

FIG. 4 is a schematic sectional view of an example of the electrophotographic photosensitive member of the present invention.

FIG. 5 is a schematic sectional view of an example of the electrophotographic photosensitive member of the present invention.

FIG. 6 is a schematic sectional view of an example of the electrophotographic photosensitive member of the present invention.

FIG. 7 is a schematic sectional view of an example of the electrophotographic photosensitive member of the present invention.

FIG. 8 is a schematic configuration diagram of an example of an electrophotographic apparatus of the present invention.

[Explanation of symbols]

1 ... Charge generating layer, 2 ... Charge transporting layer, 3 ... Conductive support,
4 ... Undercoat layer, 5 ... Protective layer, 6 ... Photoconductive layer, 10 ... Photoconductor, 11 ... Contact charging member, 12 ... Power supply, 13 ... Exposure device, 14 ... Developing device, 15 ... Transfer device, 16 ... Cleaning device, 17 ... Static eliminator, 18 ... Fixing device.

Claims (10)

[Claims] 1. An impurity is removed by dropping a solvent capable of precipitating the charge transporting resin into a solution of the charge transporting resin containing a low molecular weight component as a by-product to reprecipitate it. For purifying a charge-transporting resin. 2. The method for purifying a charge-transporting resin according to claim 1, wherein the charge-transporting resin is a charge-transporting polycarbonate resin or a charge-transporting polyester resin. 3. The method for purifying a charge-transporting resin according to claim 1 or 2, wherein the charge-transporting polycarbonate resin or the charge-transporting polyester resin is a resin having a triarylamine structure. 4. The charge-transporting polycarbonate resin or charge-transporting polyester resin is represented by the following general formula (I-1):
Or a repeating unit containing at least one kind of the partial structure represented by (I-2).
4. The method for purifying a charge transporting resin according to claim 3. Embedded image (Here, R ₁ to R ₄ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a substituted amino group, a halogen atom, or a substituted or unsubstituted aryl group, and X is a substituted or unsubstituted divalent group. Represents an aromatic group of
Represents a divalent hydrocarbon group having 1 to 10 carbon atoms which may be branched, and k and l each represent 0 or 1. ) 5. The charge according to claim 1, wherein the charge-transporting polycarbonate resin or the charge-transporting polyester resin is represented by the following general formulas (II) to (IV). Purification method of transportable resin. Embedded image [Where A is the above general formula (I-1) or (I-2)
Represents a partial structure represented by, B is -O- (Y'-O)
_{m '-} or an -Z'- (However, Y' and Z '
Each represents a divalent hydrocarbon group, and m ′ represents an integer of 1 to 5. ), Y and Z each represent a divalent hydrocarbon group, m represents an integer of 1 to 5, n represents 0 or 1, and p, p ′ and p ″ represent an integer of 5 to 5000. .] 6. A method of removing impurities by dropping a solvent capable of precipitating the charge transporting resin into a solution of the charge transporting resin containing a low molecular weight component as a by-product to cause reprecipitation to remove impurities. A charge transporting resin characterized by the above. 7. An electrophotographic photosensitive member, wherein the surface layer contains a charge-transporting polycarbonate resin or a charge-transporting polyester resin obtained by the method for purifying a charge-transporting resin according to claim 1. 8. The surface layer contains a charge-transporting polycarbonate resin or charge-transporting polyester resin obtained by the method for purifying a charge-transporting resin according to claim 1, and a phthalocyanine pigment as a charge-generating material. The electrophotographic photoreceptor according to claim 7, which is characterized in that. 9. The phthalocyanine pigment contains at least one selected from a gallium halide phthalocyanine crystal, a halogenated tin phthalocyanine crystal, a hydroxygallium phthalocyanine crystal and an oxytitanium phthalocyanine crystal. Electrophotographic photoreceptor. 10. An electrophotographic apparatus having a photoconductor and a charging member, which is arranged so as to be in contact with the photoconductor and to which a voltage is applied, wherein the photoconductor is the electron according to claim 7. An electrophotographic apparatus, which is a photographic photoreceptor.