JPH09265201A - Electrophotographic photoreceptor - Google Patents

Abstract

(57) [Summary] (Modified) [PROBLEMS] To provide an electrophotographic photoreceptor having high sensitivity and excellent durability, which contains a resin having a charge transporting ability and high mechanical strength in a photosensitive layer. SOLUTION: The electrophotographic photoreceptor is provided with a photosensitive layer containing an aromatic polycarbonate resin comprising a repeating unit represented by the following general formula (I) as an active ingredient on a conductive support.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly to a highly sensitive and highly durable electrophotographic photoreceptor containing an aromatic polycarbonate resin having a charge transporting ability in a photosensitive layer.

[0002]

2. Description of the Related Art In recent years, organic photoconductors (OPC) have been used in copying machines,
It is often used in printers. As a typical configuration example of the organic photoreceptor, a charge generation layer (CG) is formed on a conductive substrate.
L) and a charge transport layer (CTL) are sequentially laminated. The charge transport layer is a low molecular charge transport material (CT
M) and a binder resin. However,
The inclusion of the low molecular weight charge transport material reduces the mechanical strength originally possessed by the binder resin, which causes abrasion, scratches, cracks, etc. of the photoconductor and impairs the durability of the photoconductor. There is.

As a photoconductive polymer material, vinyl polymers such as polyvinylanthracene, polyvinylpyrene and poly-N-vinylcarbazole have been studied as charge transfer complex type photoconductors for a long time, but they are satisfactory in terms of photosensitivity. It wasn't possible. On the other hand, in order to improve the above-mentioned drawbacks of the laminated type photoreceptor, studies have been conducted on a polymer material having a charge transporting ability. For example, an acrylic resin having a triphenylamine structure [M. Stolka et al.
Polym. Sci. , Vol 21, 969 (198
3)], a vinyl polymer having a hydrazone structure (Jap)
an HardCopy '89P. 67) and a polycarbonate resin having a triarylamine structure (US Pat. Nos. 4,801,517, 4,806,443, 4,806,444, 4,937,165, and 4,959, US Pat. Nos. 288, 5,030,532, 5,034,296, 5,080,989, JP-A-64-9964, JP-A-3-221522.
JP-A-2-304456, JP-A-4-11627
JP-A-4-175337, JP-A-4-18371
Japanese Patent Laid-Open No. 4-31404, Japanese Patent Laid-Open No. 1333065
However, they have not been put to practical use yet.

In addition, M. A. Abkowitz et al. Compared a low molecular weight dispersion type and a polymerized polycarbonate using a tetraarylbenzidine derivative as a model compound, and obtained a result that a polymer system has a drift mobility lower by one digit. Physical Review B
46 6705 (1992)]. Although the cause of this is not clear, it suggests that there are problems in electrical characteristics such as sensitivity and residual potential, although the mechanical strength is improved by polymerizing.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances of the prior art, and by using an aromatic polycarbonate resin having a charge transporting ability,
It is an object of the present invention to provide an electrophotographic photoreceptor having high sensitivity and high durability.

[0006]

Means for Solving the Problems As a result of intensive investigations by the present inventors, a novel aromatic polycarbonate resin comprising a repeating unit represented by the following general formula (I) and a following general formula (II The present invention was found to solve the above problems by providing a photosensitive layer containing a novel aromatic polycarbonate resin composed of the repeating units represented by the formulas (3) and (III) as an active ingredient, and arrived at the present invention.

That is, the present invention is the following (1) to (4). (1) An electrophotographic photoreceptor, comprising a conductive layer and a photosensitive layer containing an aromatic polycarbonate resin comprising a repeating unit represented by the following general formula (I) as an active ingredient.

[0008]

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[In the formula, n is an integer of 5 to 5000, Ar ³
And Ar ⁴ are divalent groups of the same or different aromatic hydrocarbons,
Ar ¹ , Ar ² , Ar ⁵ and Ar ⁶ represent the same or different, substituted or unsubstituted aromatic hydrocarbon group, or substituted or unsubstituted heterocyclic group. X is an aliphatic divalent group, a cycloaliphatic divalent group, or

[0010]

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Here, R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group or a halogen atom, and 1 and m are each independently 0 to 0. 4 is an integer, Y is a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O -, - S -, - SO -, - SO 2 -,

[0012]

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Z represents a divalent group of an aliphatic hydrocarbon, a is an integer of 0 to 20, b is an integer of 1 to 2000, and R ³ and R ⁴ are independently substituted or unsubstituted. Represents an alkyl group or a substituted or unsubstituted aromatic hydrocarbon group. (2) The following general formulas (II) and (II
For electrophotography, which is provided with a photosensitive layer comprising an aromatic polycarbonate resin which is composed of the repeating unit represented by I) and has a composition ratio of repeating units of 0 <k / (k + j) ≦ 1. Photoconductor.

[0014]

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[Wherein k is an integer of 5 to 5000 and j is 0]
˜5000, Ar ³ and Ar ⁴ are divalent radicals of the same or different aromatic hydrocarbons, Ar ¹ , Ar ² , Ar ⁵ and Ar ⁶
Are the same or different substituted or unsubstituted aromatic hydrocarbon groups, or substituted or unsubstituted heterocyclic groups. X
Is an aliphatic divalent group, a cycloaliphatic divalent group, or

[0016]

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Here, R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group or a halogen atom, and 1 and m are each independently 0 to 0. 4 is an integer, Y is a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O -, - S -, - SO -, - SO 2 -,

[0018]

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Z represents a divalent group of an aliphatic hydrocarbon, a is an integer of 0 to 20, b is an integer of 1 to 2000, and R ³ and R ⁴ are independently substituted or unsubstituted. Represents an alkyl group or a substituted or unsubstituted aromatic hydrocarbon group. (3) The electrophotographic photoreceptor according to (1) above, which is an aromatic polycarbonate resin comprising a repeating unit represented by the following general formula (IV).

[0020]

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[Wherein n, Ar ¹ , Ar ² , Ar ⁵ and A
r ⁶ and X have the same meanings as in the above (1)] (4) Constituting repeating units represented by the following general formulas (V) and (III), wherein the composition ratio of the repeating units is 0 <k /
The electrophotographic photoreceptor according to (2) above, which is an aromatic polycarbonate resin having (k + j) ≦ 1.

[0022]

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[Wherein k, j, Ar ¹ , Ar ² , Ar ⁵ ,
Ar ⁶ and X are synonymous with the above (2)] As described above, the electrophotographic photoreceptor of the present invention comprises the repeating unit represented by the above general formula (I) having a tertiary amine structure in the photosensitive layer. An aromatic polycarbonate resin or an aromatic polycarbonate resin comprising a repeating unit represented by the general formula (II) having a tertiary amine structure and a repeating unit represented by the general formula (III) is contained. Since these aromatic polycarbonate resins have charge transporting ability and high mechanical strength, the present photoreceptor has high sensitivity and high durability. Hereinafter, the present invention will be described in more detail.

As described above, the electrophotographic photoreceptor of the present invention comprises an aromatic polycarbonate resin comprising the repeating unit represented by the general formula (I) or the repeating unit represented by the general formula (II) in the photosensitive layer. The aromatic polycarbonate resin contains a repeating unit represented by the general formula (III), and these aromatic polycarbonate resins are novel substances and are produced by the following method.

The aromatic polycarbonate resin used in the present invention can be produced by a conventional method for producing a polycarbonate resin in the same manner as in the known polymerization of bisphenol and a carbonic acid derivative. That is, the aromatic polycarbonate resin comprising a repeating unit having a tertiary amino group represented by the general formula (II) or (V) used in the present invention is represented by the general formula (VI) or the general formula (VII). Produced by a transesterification method of a diol compound having a tertiary amino group with a bisaryl carbonate, a phosgene method by solution or interfacial polymerization with phosgene, or a bischloroformate method using a bischloroformate derived from a diol. To be done. At this time, by using the diol represented by the following general formula (VIII) in combination, the above general formula (I
An aromatic polycarbonate resin comprising a repeating unit having a tertiary amino group represented by I) and a repeating unit represented by the general formula (III) or a repeating unit having a tertiary amino group represented by the general formula (V). An aromatic polycarbonate resin comprising a unit and a repeating unit represented by the above general formula (III) can be produced, and by doing so, an aromatic polycarbonate resin having desired properties can be obtained. The ratio of the repeating unit having a tertiary amino group represented by the general formula (II) to the repeating unit represented by the general formula (III) and the tertiary amino group represented by the general formula (V). The ratio of the repeating unit to the repeating unit represented by the general formula (III) can be selected from a wide range depending on the desired characteristics.

An aromatic polycarbonate resin comprising a repeating unit having a tertiary amino group represented by the above general formula (I) or (IV) has the following general formula (VI) or (VI).
It can be obtained by interfacial polymerization or solution polymerization of a diol compound having a tertiary amino group represented by I) and a bischloroformate derived from the following general formula (VIII). It can also be obtained by polymerizing a bischloroformate derived from a diol compound having a tertiary amino group represented by the general formulas (VI) and (VII) and a diol represented by the general formula (VIII).

[0027]

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HO-X-OH
(VIII) [Ar ^{1 to} Ar ⁶ , X in each formula are the same as defined above. The production method will be described in more detail below. In the transesterification method, the diol compound and the bisaryl carbonate are mixed in the presence of an inert gas, and the pressure is usually reduced to 120-
React at 350 ° C. The degree of reduced pressure is changed stepwise, and finally the phenols produced at 1 mmHg or less are distilled out of the system. The reaction time is usually about 1 to 4 hours. Moreover, you may add a molecular weight regulator and antioxidant as needed. Examples of the bisaryl carbonate include diphenyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl carbonate, and dinaphthyl carbonate.

In the phosgene method, the reaction is usually carried out in the presence of a deoxidizing agent and a solvent. As the deoxidizing agent, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, pyridine and the like are used. As the solvent, for example, dichloromethane,
A halogenated hydrocarbon such as chlorobenzene is used. In order to accelerate the reaction, for example, tertiary amine
A catalyst such as a primary ammonium salt can be used, and it is desirable to use a terminal terminating agent such as phenol or p-tert-butylphenol as a molecular weight modifier. The reaction temperature is usually 0 to 40 ° C., the reaction time is several minutes to 5 hours, and the pH during the reaction is usually preferably kept at 10 or higher.

When bischloroformate is used, it can be obtained by dissolving a diol compound in a solvent, adding a deoxidizing agent, and adding bischloroformate thereto. As deoxidizing agents, tertiary amines such as trimethylamine, triethylamine, tripropylamine and pyridine are used. Examples of the solvent used in the reaction include dichloromethane, dichloroethane, trichloroethane,
Tetrachloroethane, trichlorethylene, halogenated hydrocarbons such as chloroform and tetrahydrofuran,
Cyclic ether solvents such as dioxane are preferred.
Further, as the molecular weight regulator, for example, phenol, pt
It is desirable to use a terminating agent such as ert-butylphenol. The reaction temperature is usually 0 to 40 ° C., and the reaction time is several minutes to 5 hours.

Additives such as antioxidants, light stabilizers, heat stabilizers, lubricants and plasticizers can be added to the aromatic polycarbonate resin produced according to the above method, if necessary. Hereinafter, the aromatic polycarbonate resin used in the present invention will be described in more detail.

The aromatic polycarbonate resin used in the present invention is a homopolymer comprising a repeating unit represented by the general formula (II) or (V), or a repeating polymer represented by the general formula (I) or (IV). Any of alternating copolymers composed of units, and also random or block copolymers having repeating units represented by the general formulas (II) and (III) or the general formulas (V) and (III) as constitutional units. But it's okay. The molecular weight of the aromatic polycarbonate resin used in the present invention is 1,000 to 1,000,000, preferably 5,000 to 5 in terms of polystyrene-reduced number average molecular weight.
00000.

Ar ¹ , Ar ² , Ar ⁵ in each general formula,
Ar ⁶ represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group. Specific examples thereof include aromatic hydrocarbon groups such as a phenyl group, a naphthyl group, a biphenylyl group and a terphenylyl group. Group, pyrenyl group, fluorenyl group, 9,9-dimethyl-2-fluorenyl group, and the like, and the heterocyclic group includes thienyl group, benzothienyl group, furyl group, benzofuranyl group, carbazolyl group, and the like.

The above-mentioned aromatic hydrocarbon group and heterocyclic group may have the following groups as a substituent. (1) Halogen atom, cyano group, nitro group.

(2) Alkyl group; preferably C _{1 to} C ₁₂
Particularly, C _{1 to} C ₈ , more preferably C _{1 to} C ₄ linear or branched alkyl groups, and these alkyl groups further include a fluorine atom, a hydroxyl group, a cyano group, a C _{1 to} C ₄ alkoxy group, It may contain a phenyl group or a phenyl group substituted with a halogen atom, a C ₁ -C ₄ alkyl group or a C ₁ -C ₄ alkoxy group. Specifically, a methyl group,
Ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group, n-butyl group, i-butyl group, trifluoromethyl group, 2-hydroxyethyl group, 2-cyanoethyl group, 2 -Ethoxyethyl group, 2-methoxyethyl group, benzyl group, 4-chlorobenzyl group, 4-methylbenzyl group, 4-methoxybenzyl group and the like can be mentioned.

(3) Alkoxy group (-OR ⁵ ); R ⁵ represents the alkyl group defined in (2) above. Specifically, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, t-butoxy group, n-butoxy group, s-butoxy group, i-butoxy group, 2-hydroxyethoxy group, 2
-A cyanoethoxy group, a benzyloxy group, a 4-methylbenzyloxy group, a trifluoromethoxy group and the like.

(4) Aryloxy group: Examples of the aryl group include a phenyl group and a naphthyl group. This is C ₁ ~
An alkoxy group having C _4, may contain an alkyl group or a halogen atom C ₁ -C ₄ as a substituent. Specific examples include a phenoxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 4-methylphenoxy group, a 4-methoxyphenoxy group, a 4-chlorophenoxy group and a 6-methyl-2-naphthyloxy group. . (5) Substituted mercapto group or aryl mercapto group;
Specific examples include a methylthio group, an ethylthio group, a phenylthio group, a p-methylphenylthio group and the like.

(6) Alkyl-substituted amino group: The alkyl group represents the alkyl group defined in (2). In particular,
Dimethylamino group, diethylamino group, N-methyl-N
Examples include -propylamine group and N, N-dibenzylamino group. (7) Acyl group: Specific examples thereof include an acetyl group, a propionyl group, a butyryl group, a malonyl group, and a benzoyl group.

Specific examples of Ar ³ and Ar ⁴ which represent a divalent group of aromatic hydrocarbon in each general formula include divalent ones such as benzene, naphthalene, biphenyl, terphenyl, pyrene, fluorene and 9,9-dimethylfluorene. Represents a group.
The divalent group of these aromatic hydrocarbons may have an alkyl group, an alkoxy group and a halogen atom as a substituent. The alkyl group serving as a substituent is a C _{1 to} C ₅ linear or branched alkyl group, and these alkyl groups may further contain a fluorine atom. Specifically, methyl group, ethyl group, n-propyl group, i-propyl group, t-
Examples thereof include a butyl group, s-butyl group, n-butyl group, i-butyl group and trifluoromethyl group. The alkoxy group serving as a substituent is a C _{1 to} C ₅ linear or branched alkoxy group, specifically, a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, a t-butoxy group. , N-butoxy group, s-butoxy group, i-butoxy group and the like. Specific examples of the substituted or unsubstituted alkyl group in the general formulas R ^{1 to} R ⁴ include the examples shown in (2) above. When R ^{1 to} R ⁴ are substituted or unsubstituted aromatic hydrocarbon groups, specific examples thereof include substituted or unsubstituted phenyl groups and biphenyl groups.

Specific examples of the diol compound represented by the general formula (VIII) are shown below. 1,3-propanediol,
1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 2-methyl-1,3-
Propanediol, 2,2-dimethyl-1,3-propanediol, 2-ethyl-1,3-propanediol,
Aliphatic diols such as diethylene glycol, triethylene glycol, polyethylene glycol and polytetramethylene ether glycol, and cyclic aliphatic diols such as 1,4-cyclohexanediol, 1,3-cyclohexanediol and cyclohexane-1,4-dimethanol are mentioned. To be

As the diol having an aromatic ring,
4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2 -Bis (4-hydroxyphenyl) propane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-
Bis (4-hydroxyphenyl) cyclopentane, 2,
2-bis (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis (3-isopropyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 4,4′-dihydroxydiphenylsulfone,
4'-dihydroxydiphenylsulfoxide, 4,4 '
-Dihydroxydiphenyl sulfide, 3,3'-dimethyl-4,4'-dihydroxydiphenyl sulfide,
4,4'-dihydroxydiphenyl oxide, 2,2-
Bis (4-hydroxyphenyl) hexafluoropropane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxyphenyl) xanthene, ethylene glycol-bis (4-hydroxybenzoate), diethylene glycol- Bis (4-hydroxybenzoate), triethylene glycol-bis (4
-Hydroxybenzoate), 1,3-bis (4-hydroxyphenyl) -tetramethyldisiloxane, phenol-modified silicone oil and the like. 1 to 6 are sectional views of the photoconductor of the present invention.

The photoreceptor of the present invention comprises a photosensitive layer 2 containing one or more of the above aromatic polycarbonate resins.
(2 ′, 2 ″, 2 ′ ″, 2 ″ ″, 2 ′ ″ ″), but depending on the way of applying these, FIG. 1, FIG. 2, FIG. It can be used as shown in FIG. 4, FIG. 5 or FIG.

The photosensitive member shown in FIG. 1 comprises a conductive support 1 and a photosensitive layer 2 comprising a sensitizing dye, an aromatic polycarbonate resin, and a binder (binder resin) in some cases. The aromatic polycarbonate resin here acts as a photoconductive substance, and the generation and transfer of charge carriers required for light attenuation are performed via the aromatic polycarbonate resin. However, since the aromatic polycarbonate resin has almost no absorption in the visible region of light, for the purpose of forming an image with visible light, a sensitizing dye having absorption in the visible region is added for sensitization. There is a need.

In the photosensitive member shown in FIG. 2, a photosensitive layer 2'wherein a charge generating substance 3 is dispersed in a charge transport medium 4 composed of an aromatic polycarbonate resin alone or in combination with a binder is provided on a conductive support 1. It has been done. The aromatic polycarbonate resin here alone or in combination with a binder forms a charge transport medium, while the charge generating substance 3
(Charge-generating substances such as inorganic or organic pigments) generate charge carriers. In this case, the charge transport medium 4 is mainly responsible for receiving the charge carriers generated by the charge generating substance 3 and transporting them. The basic condition of this photoreceptor is that the charge generating substance and the aromatic polycarbonate resin do not overlap each other in the absorption wavelength region mainly in the visible region. This is because it is necessary to transmit light to the surface of the charge generating substance 3 in order to efficiently generate charge carriers in the charge generating substance 3. The aromatic polycarbonate resin represented by the repeating unit of the general formula (I) has almost no absorption in the visible region and is particularly effective when combined with the charge generating substance 3 which absorbs light in the visible region and generates a charge carrier. Its characteristic is that it works as a charge transport material. A low molecular weight charge transport material may be used in combination in the charge transport medium 4.

The photoconductor in FIG. 3 is a photoconductive layer 2'having a laminate of a charge generation layer 5 having a charge generation substance 3 as a main component and a charge transport layer 4 containing an aromatic polycarbonate resin on a conductive support 1. 'Is provided. In this photoreceptor, the light transmitted through the charge transport layer 4 reaches the charge generation layer 5 and the charge carriers are generated in that region, while the charge transport layer 4 receives the injection of the charge carriers and transports them. ,
Generation of charge carriers necessary for light attenuation is performed by the charge generating substance 3, and transport of charge carriers is performed by the charge transport layer 4. Such a mechanism is the same as that explained for the photoconductor shown in FIG.

The charge transport layer 4 is formed by using the aromatic polycarbonate resin of the present invention alone or in combination with a binder. In addition, the aromatic polycarbonate resin of the present invention may be contained in the charge generation layer 5 in order to increase the charge generation efficiency. For the same purpose, a low molecular weight charge transport material may be used in combination in the photosensitive layer 2 ″. The same applies to the photosensitive layers 2 ″ ″ to 2 ″ ″ ″ described below.

The photoreceptor shown in FIG. 4 has a protective layer 6 provided on the charge transport layer 4. In the case of this constitution, a protective layer is formed on the charge transport layer 4 in combination with the aromatic polycarbonate resin or the binder of the present invention. As a matter of course, it is effective to form it on the low molecular weight dispersion type charge transport layer which has been often used conventionally. The photosensitive layer 2'shown in FIG.
A protective layer may likewise be provided on top.

The photoconductor in FIG. 5 corresponds to the charge generation layer 5 in FIG.
And charge transport layer 4 containing aromatic polycarbonate resin
The stacking order is reversed, and the mechanism of charge carrier generation and transport can be the same as that described above. In this case, considering the mechanical strength, the protective layer 6 may be provided on the charge generation layer 5 as shown in FIG.

In order to actually prepare the photoconductor of the present invention, the photoconductor shown in FIG. 1 is dissolved by dissolving one or more aromatic polycarbonate resins in combination with a binder. A photosensitive layer 2 may be formed by preparing a liquid containing a sensitizing dye, coating the liquid on the conductive support 1, and drying the liquid.

The thickness of the photosensitive layer is 3 to 50 μm, preferably 5 to 20 μm. The amount of the aromatic polycarbonate resin in the photosensitive layer 2 is 30 to 100% by weight,
The amount of the sensitizing dye in the photosensitive layer 2 is 0.1 to 5% by weight, preferably 0.5 to 3% by weight. As sensitizing dyes, triarylmethane dyes such as Brilliant Green, Victoria Blue B, Methyl Violet, Crystal Violet, Acid Violet 6B, Rhodamine B, Rhodamine 6G, Rhodamine G Extra,
Examples include xanthene dyes such as eosin S, erythrosine, rose bengal and fluorescein, thiazine dyes such as methylene blue, and cyanine dyes such as cyanine.

Further, in order to manufacture the photoconductor shown in FIG.
Fine particles of the charge generating substance 3 are dispersed in a solution in which one or more aromatic polycarbonate resins or binders are used in combination, and this is coated on the conductive support 1 and dried to form the photosensitive layer 2 '. It may be formed.

The thickness of the photosensitive layer 2'is 3 to 50 μm, preferably 5 to 20 μm. The amount of the tertiary amine compound in the photosensitive layer 2'is 40 to 100% by weight,
Further, the amount of the charge generating substance 3 in the photosensitive layer 2'is 0.1 to
It is 50% by weight, preferably 1 to 20% by weight. Examples of the charge generating substance 3 include inorganic pigments such as selenium, selenium-tellurium, cadmium sulfide, cadmium sulfide-selenium, and α-silicon, and examples of organic pigments include CI Pigment Blue 25 (color index CI2118).
0), CI Pigment Red 41 (CI2120
0), CI Acid Red 52 (CI4510
0), CI Basic Red 3 (CI4521)
0), an azo pigment having a carbazole skeleton (JP-A-53-53
-95033), an azo pigment having a distyrylbenzene skeleton (JP-A-53-133445), an azo pigment having a triphenylamine skeleton (described in JP-A-53-132347), and dibenzothiophene. Azo pigments having a skeleton (described in JP-A-54-21728), azo pigments having an oxadiazole skeleton (described in JP-A-54-12742), azo pigments having a fluorenone skeleton (JP-A-54). No. 22834), an azo pigment having a bisstilbene skeleton (described in JP-A-54-17733), and an azo pigment having a distyryloxadiazole skeleton (JP-A-54-21).
29), azo pigments having a distyrylcarbazole skeleton (described in JP-A-54-14967).
Azo pigments such as CI Pigment Blue 16
Phthalocyanine-based pigments such as (CI74100), for example, CIVAT BROWN 5 (CI73410), indigo-based pigments such as CIVAT Die (CI73030), Argos Scarlet B (manufactured by Bayer), Indanthren Scarlet R (manufactured by Bayer), etc. Perylene pigments and the like. These charge generating substances may be used alone or in combination of two or more.

Further, to manufacture the photoconductor shown in FIG. 3,
A charge generating substance is vacuum-deposited on the conductive support 1, or a dispersion liquid in which fine particles 3 of the charge generating substance are dispersed in a suitable solvent in which a binder is dissolved if necessary is applied and dried. If necessary, surface finishing, film thickness adjustment, etc. are performed by a method such as buffing to form the charge generation layer 5, and one or more aromatic polycarbonate resins or a binder is used together and dissolved on the charge generation layer 5. The solution may be applied and dried to form the charge transport layer 4. The charge generating substance used for forming the charge generating layer 5 is the same as that described for the photosensitive layer 2 '.

The charge generation layer 5 has a thickness of 5 μm or less, preferably 2 μm or less, and the charge transport layer 4 has a thickness of 3 to 50.
μm, preferably 5 to 20 μm is suitable. When the charge generation layer 5 is of a type in which the fine particles 3 of the charge generation layer substance are dispersed in a binder, the proportion of the fine particles 3 of the charge generation substance in the charge generation layer 5 is 10 to 100% by weight, preferably Is about 50 to 100% by weight. The amount of the compound in the charge transport layer 4 is 40 to 100% by weight. As described above, the photosensitive layer 2 ″ in FIG. 3 may contain a low-molecular weight charge transporting substance, and the charge transporting substance used here includes the following.

Oxazole derivatives and oxadiazole derivatives (JP-A-52-139065 and JP-A-52-1390)
No. 66), an imidazole derivative, a triphenylamine derivative (described in JP-A-3-285960), a benzidine derivative (described in JP-B-58-32372), and an α-phenylstilbene derivative (JP-A-5).
7-73075), hydrazone derivatives (JP-A-55-154955, JP-A-55-156954,
No. 55-52063, No. 56-81850, etc.), triphenylmethane derivative (Japanese Patent Publication No. 5-1
0983), anthracene derivatives (described in JP-A-51-94829), styryl derivatives (described in JP-A-56-29245 and JP-A-58-198043), and carbazole derivatives (JP-A-SHO). 58-585
52), pyrene derivatives (JP-A-2-948)
No. 12)) and the like.

To make the photoreceptor shown in FIG.
The protective layer 6 is provided by dissolving and coating the aromatic polycarbonate resin of the present invention, alone or in combination with a binder, on the photoreceptor shown in FIG. The thickness of the protective layer is 0.1
It is preferably 5 to 10 μm. The amount of the aromatic polycarbonate resin of the present invention in the protective layer 6 is 40 to 100% by weight.
It is.

To prepare the photosensitive member shown in FIG. 5, a solution in which an aromatic polycarbonate resin or a binder is used in combination and dissolved is coated on the conductive support 1 and dried to form the charge transport layer 4. The charge generation layer 5 may be formed by applying a dispersion liquid in which fine particles of the charge generation layer substance are dispersed in a solvent in which a binder is dissolved on the charge transport layer, if necessary, by coating and drying by a method such as spray coating. . The amount ratio of the charge generation layer or the charge transport layer is the same as that described in FIG.

By forming the above-mentioned protective layer 6 on the charge generation layer 5 of the photoreceptor thus obtained, the structure shown in FIG.
The photoconductor shown in can be prepared. In the production of any of these photoconductors, a metal plate or metal foil such as aluminum, a plastic film on which a metal such as aluminum is vapor-deposited, or a paper subjected to a conductive treatment is used as the conductive support 1.

As the binder, condensation resins such as polyamide, polyurethane, polyester, epoxy resin, polyketone and polycarbonate, and vinyl polymers such as polyvinyl ketone, polystyrene, poly-N-vinylcarbazole and polyacrylamide are used. However,
All insulating and adhesive resins can be used. A plasticizer is optionally added to the binder, and examples of such a plasticizer include halogenated paraffin, dimethylnaphthalene, and dibutyl phthalate. Further, if necessary, additives such as an antioxidant, a light stabilizer, a heat stabilizer, and a lubricant can be added.

Further, in the photoreceptor obtained as described above, an adhesive layer or a barrier layer can be provided between the conductive support and the photosensitive layer, if necessary. Materials used for these layers include polyamide, nitrocellulose, and aluminum oxide, and the film thickness is preferably 1 μm or less.

To make a copy using the photoreceptor of the present invention,
After the photosensitive surface is charged and exposed, it is developed and transferred to paper or the like if necessary. The photoconductor of the present invention has high sensitivity,
It also has excellent durability.

[0062]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to examples. In the following examples, all parts are parts by weight. Production Example 1 A diol compound having a tertiary amino group having the following structure was used as a starting material.

[0063]

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N ', N', N ", in 30 ml of dry THF,
1.97 g (0.0023mo) N "-tetra (4-methylphenyl) -1,4-bis [α- (4-hydroxyphenyl) styryl] benzene-4 ', 4" -diamine
l), 0.70 g of triethylamine (0.0023 × 3
(mol) was dissolved. 0.558 g of diethylene glycol bischloroformate (0.0023 x
What melt | dissolved 3 mol) in 5 ml of dry THF was dripped over 30 minutes under water cooling. After the addition was complete, the viscous mixture was stirred for an additional 90 minutes and 4 wt% phenol / dry T
0.4 g of HF solution was added. After stirring for 60 minutes, the resulting viscous mixture was precipitated in methanol and the crude product was filtered off. This was treated twice with THF dissolution and methanol precipitation, and the precipitate was collected by filtration and dried to obtain a polycarbonate resin (No. 1) having the following structural formula. The desired product was 2.14 g and the yield was 91.48%.

[0065]

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(Polycarbonate resin No. 1) The molecular weight of the obtained resin was measured by gel permeation chromatography, and the molecular weight in terms of polystyrene was as follows. Number average molecular weight 1.59 × 10 ⁴ Weight average molecular weight 8.20 × 10 ⁴ The infrared absorption spectrum of this product is 1760 cm ^−1.
The absorption based on C = 0 stretching vibration of carbonate was observed. The results of elemental analysis are shown below.

[0067] Production Examples 2 to 3 In the same manner as in Production Example 1, aromatic polycarbonate resins (No. 2, 3) shown in Table 1 were obtained.

[0068]

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[0069]

[Table 1]

Production Example 4 N ′, N ′, N ″, N ″ -tetra (4-methylphenyl) -1,4-bis [α- (4-hydroxyphenyl)
Styryl] benzene-4 ', 4 "-diamine 1.71 g
(0.002 mol) was placed in a reaction vessel, and an aqueous solution in which 0.32 g (0.002 × 4 mol) of sodium hydroxide was dissolved in 200 ml of ion-exchanged water was added and stirred. 0.356 g of triphosgene under ice cooling (0.002 × 0.6mo
A solution prepared by dissolving l) in 130 ml of methylene chloride was slowly added dropwise over 20 minutes. 20m while rinsing the container
1 of methylene chloride was added. Then, 0.1 g (0.025 mol) of sodium hydroxide was added at room temperature. Further, one drop of triethylamine was added, and the mixture was stirred for 3 hours. The viscous mixture obtained was washed with 5% aqueous sodium hydroxide solution, 2% aqueous hydrochloric acid solution and ion-exchanged water, reprecipitated in methanol, the precipitate was collected by filtration, and dried to obtain a polycarbonate resin (No. 4). Obtained. The target product obtained is 1.30.
The yield was 74.6% in g. Tg point is 198.8 ° C
Met.

[0071]

[Chemical 21]

(Polycarbonate resin No. 4) The molecular weight of this product was measured by gel permeation chromatography, and the molecular weight in terms of polystyrene was as follows. Weight average molecular weight 11.6 × 10 ⁴ Number average molecular weight 1.67 × 10 ⁴ In the infrared absorption spectrum of this product, absorption based on C = 0 stretching vibration of carbonate was observed at 1780 cm ⁻¹ .
The results of elemental analysis are shown below.

[0073] Production Example 5 N ′, N ′, N ″, N ″ -tetra (4-methylphenyl) -1,4-bis [α- (4-hydroxyphenyl)
Styryl] benzene-4 ', 4 "-diamine 3.42 g
(0.004 mol) and bisphenol A 0.91 g
(0.004 mol) was placed in a reaction vessel, and an aqueous solution in which 1.28 g (0.008 × 4 mol) of sodium hydroxide was dissolved in 800 ml of ion-exchanged water was added and stirred. 1.42 g (0.008 × 0.6 mol) of triphosgene under ice cooling
Was dissolved in 500 ml of methylene chloride and slowly added dropwise over 20 minutes. 100 ml while rinsing the container
Methylene chloride was added. Then, 0.4 g of sodium hydroxide was added at room temperature. Further, one drop of triethylamine was added, and the mixture was stirred for 3 hours. The viscous mixture obtained was washed with a 5% aqueous sodium hydroxide solution, a 2% aqueous hydrochloric acid solution and ion-exchanged water, reprecipitated in methanol, the precipitate was collected by filtration, and dried to obtain a polycarbonate resin (No. 5). Obtained.
The obtained target product was 3.36 g and the yield was 74.1%. The Tg point was 189.3 ° C.

[0074]

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(Polycarbonate resin No. 5) The molecular weight of this product was measured by gel permeation chromatography, and the molecular weight in terms of polystyrene was as follows. Number average molecular weight 1.56 × 10 ⁴ Weight average molecular weight 7.63 × 10 ⁴ In the infrared absorption spectrum of this product, absorption based on C = 0 stretching vibration of carbonate was observed at 1775 cm ⁻¹ . The results of elemental analysis are shown below.

[0076] Examples are shown below, but the aromatic polycarbonate resin No. of the present invention in the examples corresponds to the above resin No.

Example 1 A polyamide resin (CM-8000: manufactured by Toray Industries, Inc.) solution dissolved in a mixed solvent of methanol / butanol was applied onto an aluminum plate with a doctor blade, and naturally dried to form an intermediate layer of 0.3 μm. . A bisazo compound represented by the following formula as a charge generating substance is pulverized by a ball mill in a mixed solvent of cyclohexanone and methyl ethyl ketone.
The obtained dispersion was applied with a doctor blade and naturally dried to form a charge generation layer having a thickness of about 1 μm.

[0078]

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Next, the polycarbonate resin No. 1 obtained in Production Example 1 as a charge transport substance was dissolved in dichloromethane, and this solution was applied onto the charge generation layer with a doctor blade, air-dried, and then at 120 ° C. After being dried for 20 minutes to form a charge transport layer having a thickness of about 20 μm, the photoconductor No.
Was produced.

Examples 2 to 5 Instead of the polycarbonate resin represented by the compound No. 1 used in Example 1, a polycarbonate resin (resin N
Nos. 2 to 5) were used and the same operation as in Example 1 was carried out to prepare photoconductors No. 2 to 5. Examples 6 to 7 Photosensitive members Nos. 6 to 7 were prepared in the same manner as in Example 1 except that the trisazo pigment of the following formula was used in place of the bisazo pigment used in Example 1.

[0081]

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The photoreceptors No. 1 to 7 thus prepared were subjected to corona discharge of -6 kV for 20 seconds in a dark place using a commercially available electrostatic copying paper tester [SP428 type manufactured by Kawaguchi Electric Co., Ltd.]. After being charged, the surface potential V of the photoconductor
_After measuring _m (V) and leaving it in the dark for 20 seconds, the surface potential V ₀ (V) was measured. Then, a tungsten lamp light is irradiated so that the illuminance on the surface of the photoconductor becomes 4.5 lux, and the time (second) until V ₀ becomes 1/2 is obtained, and the exposure amount E _1/2 (lux · sec ) Was calculated. Table 2 shows the results.

[0083]

[Table 2]

After charging each of the above photoconductors by using a commercially available electrophotographic copying machine, light irradiation is performed through the original image to form an electrostatic latent image, and the latent image is developed using a dry developer. ,
The obtained image (toner image) is electrostatically transferred onto plain paper,
When fixed, a clear transfer image was obtained. Similarly, when a wet type developer was used as the developer, a clear transfer image was obtained.

[0085]

The electrophotographic photoreceptor of the present invention comprises an aromatic polycarbonate resin comprising a repeating unit represented by the general formula (I) having a tertiary amine in the photosensitive layer, or an aromatic polycarbonate resin having a tertiary amine. The aromatic polycarbonate resin comprises a repeating unit represented by the general formula (II) and a repeating unit represented by the general formula (III), and these aromatic polycarbonate resins have charge transporting ability and high Due to its mechanical strength, the present photoreceptor has high sensitivity and high durability.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a layer structure of an electrophotographic photoreceptor according to the present invention,

FIG. 2 is a sectional view showing another example of the layer structure of the electrophotographic photoreceptor according to the present invention,

FIG. 3 is a sectional view showing another example of the layer structure of the electrophotographic photoreceptor according to the present invention,

FIG. 4 is a cross-sectional view showing another example of the layer constitution of the electrophotographic photoreceptor according to the present invention,

FIG. 5 is a cross-sectional view showing another example of the layer structure of the electrophotographic photoreceptor according to the present invention,

FIG. 6 is a cross-sectional view showing another example of the layer structure of the electrophotographic photoreceptor according to the present invention,

[Explanation of symbols]

 1 Conductive Support 2, 2 ', 2 ", 2'", 2 "", 2 '"" Photosensitive Layer 3 Charge Generating Material 4 Charge Transport Layer or Charge Transport Medium 5 Charge Generation Layer 6 Protective layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsutoshi Anzai 66-2 Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa 2 Hohodani Chemical Industry Co., Ltd. (72) Katsuhiro Morooka 66, Horikawa-cho, Kawasaki-shi, Kanagawa Address 2 In Hodogaya Chemical Co., Ltd. (72) Inventor Kazuki Nagai 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Tomoyuki Shimada 1-3-3 Nakamagome, Ota-ku, Tokyo No. 6 In Ricoh Co., Ltd. (72) Inventor Chiaki Tanaka 1-3-3 Nakamagome, Ota-ku, Tokyo In-house Ricoh Co. (72) Nozomu Tamoto 1-3-3 Nakamagome, Ota-ku, Tokyo In Ricoh Co., Ltd. (72) Inventor Ei Katayama 1-3-6 Nakamagome, Ota-ku, Tokyo In Ricoh Co., Ltd.

Claims (4)

[Claims] 1. A photoreceptor for electrophotography, comprising a photosensitive layer provided on a conductive support, the photosensitive layer containing an aromatic polycarbonate resin comprising a repeating unit represented by the following general formula (I) as an active ingredient. Embedded image [In the formula, n is an integer of 5 to 5000, Ar ³ and Ar ⁴ are divalent groups of the same or different aromatic hydrocarbons, Ar ¹ , Ar ² ,
Ar ⁵ and Ar ⁶ represent the same or different, substituted or unsubstituted aromatic hydrocarbon group, or substituted or unsubstituted heterocyclic group. X is an aliphatic divalent group, a cycloaliphatic divalent group, or Here, R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group or a halogen atom, and l and m are each independently 0.
Is an integer of 4 to 4, Y is a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O-,
-S -, - SO -, - SO 2 -, ## STR3 ## Z represents a divalent group of an aliphatic hydrocarbon, and a
Is an integer of 0 to 20, b is an integer of 1 to 2000, R ³ , R ⁴
Each independently represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aromatic hydrocarbon group. ] 2. An aromatic polycarbonate resin comprising repeating units represented by the following general formulas (II) and (III) on a conductive support, and the composition ratio of the repeating units is 0 <k / (k + j) ≦ 1. An electrophotographic photoreceptor, comprising a photosensitive layer containing as an active ingredient. Embedded image [In the formula, k is an integer of 5 to 5000, j is an integer of 0 to 5000, Ar ³ and Ar ⁴ are divalent groups of the same or different aromatic hydrocarbons, Ar ¹ , Ar ² , Ar ⁵ and Ar ⁶ are The same or different substituted or unsubstituted aromatic hydrocarbon group or substituted or unsubstituted heterocyclic group is represented. X is aliphatic 2
A valent group, a cycloaliphatic divalent group, or Here, R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group or a halogen atom, and l and m are each independently 0.
Is an integer of 4 to 4, Y is a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O-,
-S -, - SO -, - SO 2 -, embedded image Z represents a divalent group of an aliphatic hydrocarbon, and a
Is an integer of 0 to 20, b is an integer of 1 to 2000, R ³ , R ⁴
Each independently represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aromatic hydrocarbon group. ] 3. The electrophotographic photoreceptor according to claim 1, which is an aromatic polycarbonate resin comprising a repeating unit represented by the following general formula (IV). Embedded image [In the formula, n, Ar ¹ , Ar ² , Ar ⁵ , Ar ⁶ and X have the same meanings as in claim 1] 4. An aromatic polycarbonate resin comprising repeating units represented by the following general formulas (V) and (III), wherein the composition ratio of repeating units is 0 <k / (k + j) ≦ 1. Electrophotographic photoconductor. Embedded image [In the formula, k, j, Ar ¹ , Ar ² , Ar ⁵ , Ar ⁶ and X are as defined in claim 2]