JP2889652B2 - Polycarbonate polymer, method for producing the same, and electrophotographic photoreceptor using the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a polycarbonate polymer suitably used as a charge transfer material for an electrophotographic photoreceptor and a method for producing the same.

The present invention also relates to an electrophotographic photosensitive member using the polycarbonate.

[Conventional technology]

2. Description of the Related Art Recent electrophotographic photoreceptors include a stacked organic electrophotographic photoreceptor in which a photosensitive layer has at least a charge generation layer (CGL) for generating charges upon exposure and a charge transport layer (CTL) for transporting charges. (OPC) is becoming mainstream.
In this OPC, a CTL obtained by dispersing and casting a charge transfer material (CTM) in a binder resin, particularly polycarbonate (PC), is used.

In this type of conventional OPC, a large amount of CTM is dispersed and dissolved in PC as a binder resin in order to improve the photoconductivity of CTL, and the ratio of CTM is 4 to 5 parts by weight.
It also occupies a percentage. Therefore, there is a problem that the original function of PC as a binder resin for the purpose of improving printing durability is not sufficiently exhibited.

Japanese Patent Application Laid-Open No. 1-9964 discloses a polyarylamine obtained by polymerizing an arylamine compound, which is a low-molecular CTM, with an alkyl chloroformate compound or bisphenol A at a weight ratio of 1: 1. This polyarylamine is a polycarbonate having a photoconductive effect by itself, and it has been proposed that the above-mentioned problems be solved by using it for CTL instead of the conventional CTM dispersion-dissolution type. ing.

Thus, the idea of utilizing polycarbonate having photoconductivity by itself as a CTM and binder resin for CTL seems to be an effective method for solving the above-mentioned problems.

However, when the above-mentioned conventional photoconductive PC (polyarylamine) is used for CTL, there is a problem that sufficient printing durability cannot be obtained.

Also, its conventional photoconductive PC (polyarylamine)
Although the electrical characteristics of CTL as compared with the conventional dispersion-dissolution type are somewhat improved, they have not been significantly improved.

[Problems to be solved by the invention]

 The present invention has been made in view of the above circumstances.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a charge transport material (CTM) in a charge transport layer (CTL) of an electrophotographic photoreceptor (OPC).
Alternatively, it can be suitably used as a charge transfer material (CTM) and also as a binder resin, and in particular, has excellent photoconductivity, which can easily realize an electrophotographic photosensitive member having a CTL having excellent printing durability and electrical characteristics. It is an object of the present invention to provide a polycarbonate polymer having a novel structure, which is a PC and can be suitably used in various polymer material utilization fields including the field of manufacturing electrophotographic photoreceptors.

Another object of the present invention is to provide a practically advantageous method for producing a polycarbonate polymer which can be suitably used as the method for producing the polycarbonate polymer of the present invention.

Another object of the present invention is to provide an electrophotographic photoreceptor in which the above-mentioned problems have been solved and the charge transport layer (CTL) has improved electrical characteristics and improved printing durability. Is to do.

[Means for solving the problem]

The present inventors can suitably use the CTL as a charge transfer material (CTM) and a binder resin for a charge transport layer (CTL) of an organic electrophotographic photoreceptor (OPC). As a result of intensive studies to develop a new photoconductive polycarbonate capable of sufficiently improving both properties, a new repeating unit consisting of a specific repeating unit having a stilbene-based arylamine structure or a bisphenol-based repeating unit Has been found to be a photoconductive polycarbonate satisfying the above objects, and has at least two layers of an organic electrophotographic photoreceptor (OPC) having a photosensitive layer and a charge transport layer (CTL). In, by using the photoconductive polycarbonate polymer as a charge transfer material or a charge transfer material and a binder resin, It found that it is possible to obtain an electrophotographic photoreceptor excellent performance such as a charge transport layer exhibiting electrical characteristics and printing durability (CTL).

In addition, as a result of various studies on the production method of the polycarbonate polymer of the present invention, a specific dihydroxy compound having a stilbene-based arylamine structure or a bisphenol compound is reacted with a carbonate-forming compound to thereby form the polycarbonate polymer of the present invention. It has been found that polycarbonate polymers can be advantageously produced.

The present inventors have completed the present invention based on these findings.

The present invention has the following general formula: [However, Ar ¹ , Ar ² , Ar ³ and Ar ⁴ in the formula (I) are each independently Ar ⁵ and Ar ⁶ are each independently (Where R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are each independently a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, a halogen atom, an alkoxyl group , A cyano group or a nitro group, d is an integer of 1 to 5, r, k and b are each independently an integer of 1 to 4, s, t and a are each independently
It is an integer of 1 to 3, and j is 1 or 2. ),
p is 0 or 1. R ¹ and R ² are each independently a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, (Where R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom,
A hydrocarbon group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group, a cyano group or a nitro group, h is an integer of 1 to 5, e is an integer of 1 to 3, and f is 1 to 4; is there. )
Is shown. A repeating unit [I] represented by the following general formula: Wherein R ³ and R ⁴ in the formula [II] are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom or an aryl group, and u and w are each independently 1 to 4 Where X is (Where R ¹⁶ and R ¹⁷ are each independently a hydrogen atom, -C
F _{3 is} an alkyl group or an aryl group having 1 to 6 carbon atoms. ), (Where, y is an integer of _{4~10.), - (CH 2} ) v -
(Where v is an integer of 2 to 10), -O-, -S
—, —SO—, —SO ₂ — or a single bond. Wherein the composition of the repeating unit represented by the formula [I] is 0 <[I] / [I] + [II] ≦ 1 in a molar ratio. The present invention provides a polycarbonate polymer having a reduced viscosity [η _sp / C] at a temperature of 20 ° C. of a solution having a concentration of 0.5 g / dl using methylene chloride as a solvent and having a reduced viscosity of 0.2 to 5.0 dl / g.

Further, the present invention, as a practically advantageous production method of the polycarbonate polymer of the present invention, the following general formula (However, Ar ¹ , Ar ² , Ar ³ , Ar ⁴ , Ar ⁵ , Ar ⁵ in the formula (III)
⁶ , R ¹ , R ² and p each have the same meaning as in the above formula [I]. Or a dihydroxy compound [III] represented by the following general formula: (However, R ³ , R ⁴ , X, u and w in the formula [IV] each have the same meaning as in the formula [II].) A bisphenol compound [IV] represented by the following formula: The present invention provides a method for producing a polycarbonate polymer, characterized by reacting with a carbonate-forming compound to obtain the polycarbonate polymer. Further, as a particularly preferred application example of the polycarbonate polymer of the present invention, the polycarbonate polymer As an electric charge transfer material.

In the repeating unit represented by the general formula [I], that is, the repeating unit [I], the divalent group represented by Ar ¹ , Ar ² , Ar ³ or Ar ⁴ or the divalent group represented by Ar ⁵ or Ar ⁶ R ^{5 to} R ¹² relating to the monovalent group are each independently a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, a halogen atom, an alkoxyl group, a cyano group or a nitro group. 5
Examples of the hydrocarbon group include, for example, a methyl group, an ethyl group,
Alkyl groups such as propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, and unsaturated bond-containing hydrocarbon groups such as vinyl group, allyl group, butenyl group, etc. Can be mentioned. Of these hydrocarbon groups, a methyl group, an ethyl group and the like are usually preferred, and a methyl group is particularly preferred. Examples of the halogen atom relating to R ^{5 to} R ¹² include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Among these, a chlorine atom is particularly preferred.

Examples of the alkoxyl group relating to R ^{5 to} R ¹² include, for example, a methoxyl group, an ethoxyl group, a propoxyl group, an isopropoxyl group, a butoxyl group, an isobutoxyl group, a sec-butoxyl group, a tert-butoxyl group, and a pentyloxy group. Groups, an alkyloxy group such as an isopentyloxy group, a cycloalkyloxy group such as a cyclohexyloxy group, and an aryloxy group such as a phenoxy group. Among these, usually, carbon number 1-5
An alkoxyl group which is an alkyloxy group of is preferred,
Particularly, a methoxyl group and an ethoxyl group are preferable.

In each of R ^{5 to} R ¹² , among the various groups exemplified above, a methyl group and the like are particularly preferable.

Further, r, s, and r each represent the number of the substituents R ^{5 to} R ¹² .
t, j, k, d, a, and b are as described above, and all of them are preferably 1 or 2.

In the repeating unit [I], particularly preferable groups as Ar ¹ , Ar ² , Ar ³ and Ar ⁴ include a phenylene group and a naphthylene group. As the phenylene group, a 1,4-phenylene group is particularly preferred among various groups, and as the naphthylene group, a 1,4-phenylene group is preferred among various groups.
Preferred are a 4-naphthylene group, a 1,5-naphthylene group, a 2,6-naphthylene group and the like. In addition, as Ar ′, particularly,
A 4-phenylene group is preferred.

Particularly preferred groups for Ar ⁵ and Ar ⁶ include a phenyl group and a methylphenyl group.

R ¹ and R ² in the general formula [I] represent a hydrogen atom and a carbon number of 1 to 1.
5 hydrocarbon groups, [However, R ¹³ , R ¹⁴ , R ¹⁵ , h, e, and f are each as described above. However, when R ¹ or R ² is a hydrocarbon group having 1 to 5 carbon atoms, examples of the hydrocarbon group include the various hydrocarbon groups exemplified above. Among these hydrocarbon groups, a methyl group is particularly preferable.

Any one of R ¹³ , R ¹⁴ and R ¹⁵ has 1 to 5 carbon atoms
In the case of the above hydrocarbon group, examples of the hydrocarbon group include the various hydrocarbon groups exemplified above. Among these hydrocarbon groups, a methyl group and the like are particularly preferable.
When any one of R ¹³ , R ¹⁴ and R ¹⁵ is a halogen atom, examples of the halogen atom include the various halogen atoms exemplified above. Among these halogen atoms, a chlorine atom is particularly preferable.

When any one of R ¹³ , R ^14, and R ¹⁵ is an alkoxyl group, examples of the alkoxyl group include the various alkoxyl groups described above. Among these alkoxyl groups, a methoxyl group is particularly preferred.

Any one of R ¹³ , R ¹⁴ and R ¹⁵ is a cyano group,
It may be a nitro group.

H and e each representing the number of the substituents R ¹³ , R ¹⁴ and R ¹⁵
And f are as described above, respectively, and each of them is preferably 1 or 2.

Particularly preferred groups for each of R ¹ and R ² include a hydrogen atom,
Examples include a methyl group and a phenyl group. Among them
Those in which both R ¹ and R ² are phenyl groups are more preferred.

As a typical example of the repeating unit [I], for example, And the like.

In the repeating unit represented by the general formula (II), that is, the repeating unit (II), R ³ and R ⁴ are each independently
A hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom or an aryl group. Specific examples of the alkyl group include various alkyl groups exemplified as the hydrocarbon group having 1 to 5 carbon atoms and In addition, various hexyl groups such as a hexyl group, an isohexyl group, and a cyclohexyl group can be exemplified. Among these alkyl groups, a particularly preferred example is a methyl group.

Further, specific examples of the halogen atom in R ³ and R ⁴ include the various halogen atoms exemplified above. As the halogen atom, a fluorine atom and a chlorine atom are preferable.

When at least one of R ³ and R ⁴ is an aryl group, examples of the aryl group include various methylphenyl groups such as a phenyl group, a tolyl group, and a xylyl group, various ethylphenyl groups, and various propylphenyl groups. Such as alkyl group phenyl group, biphenyl group, various alkyl group biphenyl group, 1- or 2-naphthyl group, various alkylnaphthyl groups, and the like. Among these aryl groups, a phenyl group is particularly preferable.

U and w indicating the numbers of the substituents R ³ and R ⁴ are each independently an integer of 1 to 4, but preferably 1 or 2.

X in the repeating unit [II] is selected from the above-mentioned various divalent groups or single bonds.

When X is —C (R ¹⁶ R ¹⁷ ) —, R ¹⁶ and R ¹⁷ are each independently a hydrogen atom, —CF ₃ , an alkyl group having 1 to 6 carbon atoms or an aryl group. Examples of the aryl group include those described above. As a particularly preferred group as R ¹⁶ or R ¹⁷ , for example,
Examples include a hydrogen atom, a methyl group, —CF ₃ , and a phenyl group.

X is In the case of this, as the 1,1-cycloalkylidene group,
-Cyclopentylidene group, 1,1-cyclohexylidene group, 1,1-cyclooctylidene group, etc., which are integers from 4 to 10 can be mentioned. A 1-cyclohexylidene group is preferred.

When X is — (CH ₂ ) _v —, the polymethylene group is such that v such as 1,2-ethylene group, 1,3-propylene group, 1,4-butylene group, 1,8-octylene group is 2; There can be mentioned various types having an integer of up to 10.

X is, -0 -, - S -, - SO -, - SO 2 - or a single bond.

Preferred examples of X include, for example, —0—, —S—, a single bond, and the like. Among these, Are preferred.

The polycarbonate polymer of the present invention comprises a polycarbonate polymer (PC-I) comprising one or more kinds of the repeating unit [I] and one or more kinds of the repeating unit [I] and one or more kinds of the repeating unit [I]. A polycarbonate polymer (PC-I / II) comprising the above-mentioned repeating unit [II], or a mixture or composition thereof at any ratio.

In the PC-I / II, the ratio between the repeating unit [I] and the repeating unit [II] can be any ratio as long as the unit has the repeating unit [I].

That is, in the polycarbonate polymer of the present invention, the ratio of the repeating unit [I] to the repeating unit [II] is 0 <{[I] / ([I] + [II])} ≦ 1 can be arbitrarily selected.

Here, when the proportion is 0, that is, in the case of a polycarbonate having no repeating unit [I], it does not show photoconductivity as it is, for example, by dispersing and dissolving a low-molecular-weight charge transfer material in the electrophotographic photosensitive member. Even if it is used as a charge transport layer, the electrical characteristics and the printing durability cannot be sufficiently satisfied, and the object of the present invention cannot be achieved.

That is, one of the important points in the present invention is that the polycarbonate polymer has the repeating unit [I] having a specific stilbene structure.

The preferred range of the repeating unit [I] is usually 0.01 ≦ {[I] / ([I] + [II])} ≦ 1.

In addition, the polycarbonate polymer of the present invention may have other repeating units other than the above, as long as the object of the present invention is not hindered, and may be appropriately added and blended with other polymer components and additives. Can also be used.

One of the important points in the polycarbonate polymer of the present invention is that the polycarbonate polymer comprising the repeating unit [I] or the repeating unit [II] is in a specific reduced viscosity range [η _sp / C]. is there.

That is, in the polycarbonate polymer of the present invention, the reduced viscosity [η _sp / C] at a temperature of 20 ° C. of a solution having a concentration of 0.5 g / dl using methylene chloride as a solvent is 0.2 to 5.0 dl / g.

When the reduced viscosity [η _sp / C] is less than 0.2 dl / g, the original properties such as mechanical strength as a polycarbonate, especially when used in a charge transport layer of an electrophotographic photoreceptor, have sufficient printing durability. On the other hand, if it exceeds 5 dl / g, troubles such as deterioration of moldability occur.

The preferred range of the reduced viscosity (η _sp / C) is 0.6 to 1.2 dl / g.
It is.

As described above, a specific structure and a specific reduced viscosity [η _sp /
The polycarbonate polymer of the present invention having C) is a polycarbonate having photoconductivity and can be used for various applications. In particular, the charge transfer material in the charge transport layer of the electrophotographic photosensitive member as described later In particular, it can be advantageously used as a charge transfer material and a binder resin.

The production method of the polycarbonate polymer of the present invention is not particularly limited, and it can be produced by various methods according to a known method using an appropriate monomer. It can be advantageously produced by the method.

That is, a method for producing the polycarbonate polymer of the present invention in a practically advantageous manner is represented by the following general formula: (However, Ar ¹ , Ar ² , Ar ³ , Ar ⁴ , Ar ⁵ ,
Ar ⁶ , R ¹ , R ² and p each have the same meaning as in the above formula [I]. R ¹ and R ² may be either cis or trans with respect to —C ＝ C—. Or a dihydroxy compound [III] represented by the following general formula: (However, R ³ , R ⁴ , X, u and w in the formula [IV] each have the same meaning as in the formula [II].) A bisphenol compound [IV] represented by the following formula: It is carried out by reacting with a carbonate-forming compound.

Ar ^{1 to} Ar ⁶ , R ¹ , R ² and p in the general formula (III)
Further, R ^{5 to} R ¹² , d, r, k, b, s,
The description of specific examples, preferred examples or ranges, preferred ranges, and the like of t, a, and j is the same as described above.

Further, specific examples of R ³ , R ⁴ , X, u and w in the general formula [IV], and further R ^{15 to} R ¹⁷ , y and v relating thereto,
Preferred examples, ranges, preferred ranges, and the like are the same as described above.

The compound represented by the general formula [III], that is, the dihydroxy compound [III] is the same as the above Ar ^{1 to} Ar ⁶ , R ¹ , R ² and p
Further, R ^{5 to} R ¹² , d, r, k, b, s,
There are various types depending on t, a and j, and any of them can be used. Among them, as typical examples, for example, the following: And the like.

The compound represented by the general formula [IV], that is, the bisphenol compound [IV], may be selected from various compounds depending on R ³ , R ⁴ , X, u, and w, and R ^{15 to} R ¹⁷ , y, and v related thereto. And any of these can be used. Representative examples thereof include bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane and 1,2
-Bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3
-Methyl-4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4
-Hydroxyphenyl) octane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (4-hydroxyphenyl) -1,1-diphenylmethane, 1,1-bis (4-hydroxyphenyl) -1 -Phenylethane, 1,
1-bis (4-hydroxyphenyl) -1-phenylmethane, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, 1,1-bis (4- (Hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2- (3-
Methyl-4-hydroxyphenyl) -2- (4-hydroxyphenyl) -1-phenylethane, bis (3-methyl-4-hydroxyphenyl) sulfide, bis (3-
Methyl-4-hydroxyphenyl) sulfone, bis (3
-Methyl-4-hydroxyphenyl) methane, 1,1-bis (3-methyl-4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxyphenylbiphenyl, 2,2-
Bis (2-methyl-4-hydroxyphenyl) propane, 1,1-bis (2-butyl-4-hydroxy-5-methylphenyl) butane, 1,1-bis (2-tert-butyl-4-hydroxy- 3-methylphenyl) ethane, 1,1
-Bis (2-tert-butyl-4-hydroxy-3-methylphenyl) propane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) propane,
1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) butane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) isobutane,
1,1-bis (2-tert-butyl-4-hydroxy-5-
Methylphenyl) heptane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) -1-phenylmethane, 1,1-bis (2-tert-amyl-4-hydroxy-5- Methylphenyl) butane, bis (3-chloro-4-hydroxyphenyl) methane, bis (3,5-
Dibromo-4-hydroxyphenyl) methane, 2,2-bis (3-chloro-4-hydroxyphenyl) methane,
2-bis (3-chloro-4-hydroxyphenyl) propane, 2,2-bis (3-fluoro-4-hydroxyphenyl) propane, 2,2-bis (3-bromo-4-hydroxyphenyl) propane, 2 , 2-bis (3,5-dichloro-
4-hydroxyphenyl) propane, 2,2-bis (3,5-
Difluoro-4-hydroxyphenyl) propane, 2,2
-Bis (3, -bromo-4-hydroxy-5-chlorophenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4) -Hydroxyphenyl) butane, 2,2-bis (3,5-
Dibromo-4-hydroxyphenyl) butane, 1-phenyl-1,1-bis (3-fluoro-4-hydroxyphenyl) ethane, bis (3-fluoro-4-hydroxyphenyl) ether, 3,3'-difluoro- 4,4'-dihydroxybiphenyl, 1,1-bis (3-cyclohexyl-
4-hydroxyphenyl) cyclohexane and the like.

As the precarbonate-forming compound, various compounds used in a general polycarbonate production field can be used. Typical examples thereof include various carbonyl halides such as phosgene, haloformates such as a chloroformate compound, and a carbonate compound.

 Of these, phosgene is particularly preferably used.

In the method of the present invention, one or more of the dihydroxy compounds [III] is reacted with at least one of the carbonate-forming compounds to produce the polycarbonate polymer PC-I of the present invention. Alternatively, one or more of the above-mentioned dihydroxy compounds [III], one or more of the above-mentioned bisphenol compounds [IV], and at least one of the above-mentioned carbonate-forming compounds are reacted with each other. The PC-I / II, which is a polycarbonate polymer, is produced.

By appropriately selecting the ratio of the dihydroxy compound [III] and the bisphenol compound [IV] to be used, the ratio of the repeating unit [I] and the repeating unit [II] can be arbitrarily changed and adjusted.

The method of this reaction (reaction atmosphere, conditions, reaction method, operation method, and the like) is not particularly limited, and usually, a known method used in the production of polycarbonate may be appropriately applied.

For example, when a carbonyl dihalide such as phosgene or a haloformate such as chloroformate is used as the carbonate-forming compound, this reaction is carried out in an appropriate solvent in an acid acceptor (eg, an alkali metal hydroxide or an alkali metal hydroxide). The reaction can be performed in the presence of a basic alkali metal compound such as a metal carbonate or an organic base.

As the alkali metal hydroxide and the alkali metal carbonate, various types can be used, but from an economical viewpoint,
Usually, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and the like are suitably used. They are,
Usually, it is suitably used as an aqueous solution.

The proportion of the carbonate-forming compound used may be appropriately adjusted in consideration of the stoichiometric ratio of the reaction. When a gaseous carbonate-forming compound such as phosgene is used, a method of blowing the compound into the reaction system can be suitably employed.

The use ratio of the acid acceptor may be appropriately determined in the same manner in consideration of the stoichiometric ratio (equivalent) of the reaction. Specifically, the total number of moles of the dihydroxy compound [III] and the bisphenol compound [IV] to be used (normally, 1 mole is equivalent to the equivalent)
It is preferable to use 2 equivalents or a slight excess of the acid acceptor to the acid acceptor.

As the solvent, various solvents such as those used in the production of known polycarbonates may be used alone or as a mixed solvent. As a typical example, for example, a halogen compound hydrocarbon solvent such as methylene chloride can be preferably used.

In carrying out this reaction, if necessary,
The reaction rate and the molecular weight may be adjusted by adding a molecular weight regulator (for example, a monophenol or a crosslinking agent) or a reaction accelerator (for example, an alkylamine).

The reaction temperature is usually 0 to 150 ° C, preferably 5 to 40 ° C.
It is appropriate to set the range.

The reaction pressure can be any of reduced pressure, normal pressure, and pressurized pressure, but it can usually be suitably performed at normal pressure or about the self-pressure of the reaction system.

The reaction time is usually 0.5 minutes to 10 hours, preferably
About 1 minute to 2 hours is sufficient.

As a reaction method, any of a continuous method, a semi-continuous method, a batch method, and the like can be adopted.

As described above, the polycarbonate polymer of the present invention (PC-I or PC-I / II having a desired composition) can be synthesized.

The reduced viscosity [η _sp / C] of the obtained polymer can be adjusted to the above range by various methods such as selection of the reaction conditions and the amount of the molecular weight modifier used. In some cases, the obtained polymer is appropriately subjected to a physical treatment (mixing, fractionation, etc.) and / or a chemical treatment (polymer reaction, cross-linking treatment, partial decomposition treatment, etc.) to obtain a predetermined reduced viscosity [η _sp / C] can also be obtained as a polycarbonate polymer.

The obtained reaction product (crude product) can be subjected to various post-treatments such as a known separation / purification method, and recovered as a polycarbonate polymer having a desired purity (purity).

As described above, the polycarbonate polymer of the present invention can be produced in a practically advantageous manner.

 Next, the electrophotographic photosensitive member of the present invention will be described.

The electrophotographic photoreceptor of the present invention is characterized in that the polycarbonate polymer of the present invention is used as a charge transfer material.

That is, as long as the electrophotographic photoreceptor of the present invention utilizes the polycarbonate polymer of the present invention as a charge transfer material, any type of known electrophotographic photoreceptors may be used, and at least 1 An organic electrophotographic photoreceptor (OPC) having a charge generation layer (CGL) and at least one charge transport layer (CTL) is preferred.

The polycarbonate polymer of the present invention may be used in any part of an electrophotographic photoreceptor, but usually, at least one part is used.
It is used as a charge transfer material used in the charge transport layer of the layer, preferably as a charge transfer material and also as a binder resin. In the case of a multi-layer type electrophotographic photoreceptor having two charge transport layers, it is preferable to use it for all the charge transport layers.

In the electrophotographic photoreceptor of the present invention, the polycarbonate polymer of the present invention may be used singly or may be used alone.
More than one species may be used in combination as a composition or independently. Further, if desired, a binder resin component such as a polymer component such as another polycarbonate may be contained as long as the object of the present invention is not impaired, or an additive such as an antioxidant may be contained. May optionally contain another low-molecular or high-molecular charge transfer material.

The electrophotographic photoreceptor of the present invention has a photosensitive layer having a charge generation layer and a charge transport layer on a conductive substrate, and a charge transport layer may be laminated on the charge generation layer, A charge generation layer may be laminated on the charge transport layer. In addition, a conductive or insulating protective film may be formed on the surface layer as necessary. Further, an intermediate layer such as an adhesive layer for improving the adhesion between the layers or a blocking layer serving as a charge blocking layer may be formed.

The electrophotographic photoreceptor of the present invention comprises at least the above polycarbonate polymer as a binder resin in the photosensitive layer, preferably in the charge transport layer in the photosensitive layer.

As the conductive substrate material used in the electrophotographic photoreceptor of the present invention, various materials such as known materials can be used, and specifically, for example, aluminum, brass,
Conduction treatment was performed by coating a conductive material such as aluminum, nickel, chromium, palladium, and graphite on a metal plate or metal sheet such as copper, nickel, steel, or a black sheet by vapor deposition, sputtering, or coating. A material obtained by subjecting a substrate such as glass, plastic plate, cloth, paper, or the like to a conductive treatment can be used.

The charge generation layer has at least a charge generation material, and the charge generation layer can be obtained by forming a layer formed by binding the charge generation material using a binder resin on a base substrate thereof. it can. As a method for forming the charge generation layer, various methods such as a known method can be used, and usually, for example, a coating solution in which a charge generation material is dispersed or dissolved in a suitable solvent together with a binder resin is applied to a predetermined base. A method of applying the composition on a substrate to be dried and drying the composition can be suitably used.

As the charge generation material in the charge generation layer, various materials such as known materials can be used, and specifically, for example, selenium alone such as amorphous selenium and trigonal selenium, and selenium such as selenium-tellurium alloy, selenide or selenium-containing compositions, such as As ₂ Se _3, zinc oxide, CdS-Se
Inorganic materials comprising Group II and Group IV elements such as, oxide-based semiconductors such as titanium oxide, various inorganic materials such as silicon-based materials such as amorphous silicon, metal or metal-free phthalocyanine, cyanine, anthracene, pyrene,
Examples include various organic materials such as perylene, pyrylium salt, thiapyrimim salt, polyvinyl carbazole, and squarium pigment.

These may be used alone or in a combination of two or more.

The binder resin in the charge generation layer is not particularly limited, and various resins such as known ones can be used. Specifically, for example, polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl chloride-vinyl acetate copolymer, polyvinyl Acetal, alkyd resin, acrylic resin, polyacrylonitrile, polycarbonate, polyamide, polyketone,
Thermoplastic resins such as polyacrylamide, butyral resin, and polyester, and thermosetting resins such as polyurethane, epoxy resin, and phenol resin can be used.

The polycarbonate polymer may be used as the binder resin in the charge generation layer.

The charge transport layer can be obtained by forming a layer formed by binding a charge transfer material with a binder resin on a substrate, which is a base of the charge transport layer.

As a method for forming the charge transport layer, various methods such as a known method can be used.However, usually, for example, a coating liquid in which a charge transfer material is dispersed or dissolved in a suitable solvent together with a binder resin is prepared by a predetermined method. For example, a method of applying the composition on a substrate serving as an underlayer and drying the applied composition can be suitably used.

As the charge transfer material in the charge transfer layer, any of the conventionally used electron transfer materials and hole transfer materials can be used together with the charge transfer material of the present invention.

Specific examples of the electron transfer material include, for example, chloroanil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-tetra Electron-withdrawing substances such as fluorenone, 2,4,7-trinitro-9-dicyanomethylene fluorenone, 2,4,5,7-tetranitroxanthone, 2,4,9-trinitrothioxanthone, and these electron-withdrawing substances There are molecularized ones. These may be used alone or in a combination of two or more.

As the hole-transporting substance, pyrene, N-ethylcarbazole, N-isopropylcarbazole, N-methyl-
N-phenylhydrazino-3-methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-10-ethylphenothiazine, N , N-Diphenylhydrazino-3-methylidene-10
-Ethylphenoxazine, p-diethylaminobenzaldehyde-N, N-diphenylhydrazone, p-diethylaminobenzaldehyde-N-α-naphthyl-N-phenylhydrazone, p-pyrrolidinobenzaldehyde-N,
N-diphenylhydrazone, 1,3,3-trimethylindolenine-ω-aldehyde-N, N-diphenylhydrazone,
Hydrazones such as p-diethylbenzaldehyde-3-methylbenzthiazolinone-2-hydrazone, 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1-phenyl-3- ( p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [quinolyl (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl)
Pyrazoline, 1- [repidyl (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazolin, 1- [6-methoxy-pyridyl (2)]-3- (p-diethylaminostyryl ) -5
(P-diethylaminophenyl) pyrazolin, 1- [pyridyl (5)]-3- (p-diethylaminophenyl)
Pyrazoline, 1- [pyridyl (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazolin, 1- [pyridyl (2)]-3- (p
-Diethylaminostyryl) -4-methyl-5- (p-
Diethylaminophenyl) pyrazolin, 1- [pyridyl (2)]-3- (α-methyl-p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazolin, 1-phenyl-3- (p-diethylaminostyryl)- 4-methyl-5- (p-diethylaminophenyl) pyrazolin, 1-phenyl-3 (α-benzyl-p
Pyrazolines such as -diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline and spiropyrazoline, 2- (p-diethylaminostyryl) -δ-diethylaminobenzoxazole, 2- (p-diethylaminophenyl) -4- (p- Oxazole compounds such as dimethylaminophenyl) -5- (2-chlorophenyl) oxazole, thiazole compounds such as 2- (p-diethylaminostyryl) -6-diethylaminobenzothiazole, bis (4-diethylamino-2-methylphenyl) Triarylmethane compounds such as -phenylmethane, 1,1-bis (4-N, N-diethylamino-2-methylphenyl) heptane, 1,1,2,2-tetrakis (4-
Polyarylamines such as (N, N-dimethylamino-2-methylphenyl) ethane, N, N'-diphenyl-N, N'-
Bis (methylphenyl) benzidine, N, N'-diphenyl-N, N'-bis (ethylphenyl) benzidine, N, N '
-Diphenyl-N, N'-bis (propylphenyl) benzidine, N, N'-diphenyl-N, N'-bis (butylphenyl) benzidine, N, N'-diphenyl-N, N'-bis (isopropylphenyl ) Benzidine, N, N'-diphenyl-N, N'-bis (secondary butylphenyl) benzidine, N, N'-diphenyl-N, N'-bis (tertiary butylphenyl) benzidine, N, N Benzidine compounds such as' -diphenyl-N, N'-bis (chlorophenyl) benzidine, triphenylamine, poly-N-vinylcarbazole, polyvinylpyrene, polyvinylanthracene, polyvinylacridine, poly-9-vinylphenylanthracene, pyrene- Formaldehyde resin, ethylcarbazole-formaldehyde resin and the like can be mentioned.

These may be used alone or in a combination of two or more.

Specific examples of the solvent used in forming the charge generation layer and the charge transport layer include, for example, benzene, toluene, xylene, aromatic solvents such as chlorobenzene, acetone, methyl ethyl ketone, ketones such as cyclohexanone, methanol, Ethanol, alcohols such as isopropanol, ethyl acetate, esters such as ethyl cellosolve, carbon tetrachloride, carbon tetrabromide, chloroform, dichloromethane, halogenated hydrocarbons such as tetrachloroethane,
Examples thereof include ethers such as tetrahydrofuran and dioxane, dimethylformamide, dimethylsulfoxide, and diethylformamide.

These solvents may be used alone or in combination of two or more.

The application of each layer can be performed using various coating apparatuses such as known ones, and specifically, for example, can be performed using an applicator, a spray coater, a bar coater, a dip coater, a roll coater, a doctor blade, or the like. it can.

The electrophotographic photoreceptor of the present invention uses a conventional polycarbonate resin or the like as a binder resin, and disperses and dissolves a conventional charge transfer material in the conventional electrophotographic photoreceptor. Excellent performance, especially in both printing durability and electrical properties, as compared with electrophotographic photoreceptors using polyarylamines (photoconductive polycarbonates) as charge transfer materials or charge transfer materials and binder resins This is an electrophotographic photoreceptor having the following, and can be advantageously used in various electrophotographic photoreceptor applications.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples, and various modifications and applications can be made without departing from the spirit of the present invention. It is.

In the following, the electrophotographic characteristics were measured using an electrostatic charging tester (EPA-8100, manufactured by Kawaguchi Manufacturing Co., Ltd.)
6kV corona discharge, initial surface potential (V _O ), residual potential (V _R ) after light irradiation (10Lux), and half-exposure (E _1/2 )
Was evaluated by measuring.

Example 1 The following structural formula was added to 600 ml of a 3N aqueous solution of sodium hydroxide. A solution in which 66.5 g (0.125 mol) of a stilbene-based dihydroxy compound described above, 33.5 g (0.125 mol) of 1,1-bis (4-hydroxyphenyl) cyclohexane was dissolved, and 250 ml of methylene chloride were introduced into one flask. The reaction solution was vigorously stirred while maintaining the liquid temperature around 10 ° C. by external cooling, and phosgene was blown in at a rate of 340 ml / min for 30 minutes.

Thereafter, stirring was continued for 1 hour to complete the polymerization. After completion of the reaction, the organic layer was diluted by adding 500 ml of methylene chloride,
After washing with water, dilute hydrochloric acid and water in that order, the resultant was poured into methanol to obtain a polycarbonate polymer.

This polymer has a concentration of 0.5 g / d using methylene chloride as a solvent.
l reduced viscosity at 20 ° C (η _sp / C) is 0.85d
l / g.

The structure and composition of the obtained polymer were analyzed by ¹ HNMR.
Analysis by spectrum confirmed that the composition consisted of the following repeating units and composition.

10 of the above polycarbonate polymer as a charge transfer material
A weight percent solution of methylene chloride was prepared.

Using a conductive substrate of aluminum, this coating solution was applied by dip coating on a charge generation layer of about 0.5 μm using the following bisazo pigment, and after drying, a charge transport layer of 20 μm was provided. The body was made. The electrophotographic characteristics of the electrophotographic photoreceptor, such as the receiving potential immediately after corona charging, the surface potential after 5 seconds in a dark place, the residual potential after light irradiation, and the half-exposure amount, are those of hydroxyarylamine compounds and diethylene glycol bischloroformate compounds. This showed a better value than the electrophotographic photoreceptor using polycarbonate obtained by copolymerizing the above (Comparative Example 1). Furthermore, the electrophotographic photoreceptor using polycarbonate made of bisphenol A as a binder resin (Comparative Example 2) showed a value better than the electrophotographic characteristics. The results are shown in Table 1. The surface hardness (pencil hardness: JIS-K-5400) of this charge transport layer was H.

Example 2 The following dihydroxy compounds as monomers Same as Example 1 except that 75.8 g (0.2 mol) and 12.8 g (0.05 mol) of 2,2-bis (3-methyl-4-hydroxyphenyl) propane were used. Polycarbonate polymer [η _{sp /} C] 0.92dl
/ g.

Using this polymer, a laminated electrophotographic photosensitive member was produced in the same manner as in Example 1. The electrophotographic characteristics were as shown in Table 1, and the surface hardness of the charge transport layer was B.

Example 3 The following dihydroxy compounds as monomers The following repeating units and compositions were prepared in the same manner as in Example 1 except that 20.4 g (0.05 mol) and 1,1-bis (4-hydroxyphenyl) -1,1-diphenylmethane 70.4 g (0.20 mol) were used. Having a polycarbonate polymer ([η _sp / C] =
0.78 dl / g).

Using this copolymer, a laminated electrophotographic photosensitive member was produced in the same manner as in Example 1. The electrophotographic characteristics were as shown in Table 1, and the surface hardness of the charge transport layer was 2H.

Comparative Example 1 Referring to Example 3 of JP-A-1-9964, N, N'-diphenyl-N, N'-bis (4-hydroxyphenyl)-
[1,1-biphenyl] -4,4'-diamine 65 g (0.125 mol) and diethylene glycol bischloroformate 23.3
From 8 g (0.125 mol), a polycarbonate ([η _sp /C]=0.72 dl / g) comprising the following repeating units was obtained.

Using this polycarbonate, a laminated electrophotographic photosensitive member was produced in the same manner as in Example 1. The electrophotographic characteristics were as shown in Table 1, and the surface hardness of the charge transport layer was B.

Comparative Example 2 Stilbene Compound as Charge Transfer Material Was prepared in the same manner as in Example 1 to prepare a 10% by weight solution of polycarbonate composed of bisphenol A containing methylene chloride. The electrophotographic characteristics are as shown in Table 1, and the surface hardness of the charge transport layer was 2B.
Met.

Example 4 The following structural formula was used as a monomer: 71.75 g (0.125 mol) of stilbene-based dihydroxy compound and 2,2-bis (4-hydroxyphenyl) propane 2
Except that 8.5 g (0.125 mol) was used, a polycarbonate copolymer ([η _sp / C] was 0.77 dl / g) having the following repeating units and composition was obtained in the same manner as in Example 1.

Using this polycarbonate copolymer, a laminated electrophotographic photosensitive member was prepared in the same manner as in Example 1.

The electrophotographic properties of this product were as shown in Table 1, and the surface hardness of the charge transport layer was H.

Example 5 The following dihydroxy compounds as monomers Was used in the same manner as in Example 1 except that 139.6 g (0.20 mol) and 13.4 g (0.05 g) of 1,1-bis (4-hydroxyphenyl) cyclohexane were used. ([Η _sp /C]=0.61dl/
g) was obtained.

Using this polycarbonate, a laminated electrophotographic photosensitive member was prepared in the same manner as in Example 1. Electrophotographic characteristics are first
As shown in the table, the surface curing of the charge transport layer was B.

Example 6 The following dihydroxy compounds as monomers Was used in the same manner as in Example 1 except that 27.3 g (0.05 mol) and 70.4 g (0.20 mol) of 1,1-bis (4-hydroxyphenyl) -1,1-diphenylmethane were used. And a polycarbonate copolymer having the above composition ([η _sp /C]=0.57 dl / g).

Using this polycarbonate, a laminated electrophotographic photosensitive member was produced in the same manner as in Example 1. Electrophotographic characteristics are first
As shown in the table, the hardness of the charge transport layer was 2H.

[Effects of the Invention] According to the present invention, the charge transport layer of the electrophotographic photoreceptor can be suitably used as a charge transfer material or a charge transfer material and also as a binder resin, and is particularly excellent in printing durability and electrical characteristics. It is an excellent photoconductive polycarbonate that can easily realize an electrophotographic photoreceptor having a transport layer, and can be suitably used in various polymer material application fields including the electrophotographic photoreceptor manufacturing field. Thus, it is possible to provide a polycarbonate polymer having a novel structure.

Further, according to the present invention, it is possible to provide a practically advantageous method for producing a polycarbonate polymer which can be suitably used as the method for producing the polycarbonate polymer of the present invention.

Further, according to the present invention, it is possible to provide a high-performance electrophotographic photoreceptor having excellent electric characteristics as a charge transport layer and an electrophotographic photoreceptor and excellent printing durability.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C08G 64/04 CA (STN) REGISTRY (STN)

Claims (3)

(57) [Claims] 1. The following general formula: [However, Ar ¹ , Ar ² , Ar ³ and Ar ⁴ in the formula (I) are each independently Ar ⁵ and Ar ⁶ are each independently (Where R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are each independently a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, a halogen atom, an alkoxyl group , A cyano group or a nitro group, d is an integer of 1 to 5, r, k and b are each independently an integer of 1 to 4, s, t and a are each independently
It is an integer of 1 to 3, and j is 1 or 2. ),
p is 0 or 1. R ¹ and R ² are each independently a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, (Where R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom,
A hydrocarbon group having 1 to 5 carbon atoms, a halogen atom, an alkoxyl group, a cyano group or a nitro group, h is an integer of 1 to 5, e is an integer of 1 to 3, and f is 1 to 4; is there. ). A repeating unit [I] represented by the following general formula: Wherein R ³ and R ⁴ in the formula [II] are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom or an aryl group, and u and w are each independently 1 to 4 Where X is (Where R ¹⁶ and R ¹⁷ are each independently a hydrogen atom, -C
F _{3 is} an alkyl group or an aryl group having 1 to 6 carbon atoms. ), (Where, y is an integer of _{4~10.), - (CH 2} ) v -
(Where v is an integer of 2 to 10), -O-, -S
—, —SO—, —SO ₂ — or a single bond. And the composition of the repeating unit represented by the formula [I] is 0 <[I] / [I] + [II] ≦ 1 in a molar ratio. A polycarbonate polymer having a reduced viscosity [η _sp / C] of 0.2 to 5.0 dl / g at a temperature of 20 ° C. of a solution having a concentration of 0.5 g / dl using methylene chloride as a solvent. 2. The following general formula: (However, Ar ¹ , Ar ² , Ar ³ , Ar ⁴ , Ar ⁵ , Ar ⁵ in the formula (III)
⁶ , R ¹ , R ² and p each have the same meaning as in the above formula [I]. Or a dihydroxy compound [III] represented by the following general formula: (However, R ³ , R ⁴ , X, u and w in the formula [IV] each have the same meaning as in the formula [II].) A bisphenol compound [IV] represented by the following formula: A method for producing a polycarbonate polymer, comprising reacting the compound with a carbonate-forming compound to obtain the polycarbonate polymer according to claim 1. 3. An electrophotographic photoreceptor comprising the polycarbonate polymer according to claim 1 as a charge transfer material.