JPH02309363A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To ensure satisfactory sensitivity to light having long wavelength such as semiconductor laser light and to increase potential stability during repeated use by using a phthalocyanine pigment, a specified sensitizer and a specified electric charge transferring material in combination. CONSTITUTION:A phthalocyanine pigment, one or more kinds of sensitizers and a hydrazone compd. represented by formula IV as an electric charge transferring material are incorporated into the photoconductive layer of the sensitive body. The sensitizers may be selected among (thio)urea compd. represented by formula I, (thio)amido compds. represented by formula II and (thio)barbituric acid compds. represented by formula III. In the formulae I-IV, Z is S or O, each of R<1>-R<4> is H, alkyl, etc., R<8> is alkyl, alkoxy, etc., each of R<9> and R<10> is alkyl, aryl, etc., R<11> is H, alkyl, etc., each of R<12> and R<13> is alkyl, aralkyl, etc., R<14> is H, alkyl, etc., each of Ar1 and Ar2 is arom. hydrocarbon or a hetero ring and n is 0 or 1.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention relates to an electrophotographic photoreceptor comprising a photoconductive layer comprising a charge generating material, a charge transporting material, and a sensitizer on a conductive support. It is.

"Conventional Technology J Electrophotographic photoreceptors that are sensitive to visible light have been developed for application in copying machines, optical printers, etc. Conventionally, such electrophotographic photoreceptors have been made using selenium, zinc oxide, etc. ,
Photoreceptors containing inorganic photo-R'R materials such as cadmium sulfide as a main component have been widely used. However, such inorganic photoreceptors do not necessarily satisfy the performance required for electrophotographic photoreceptors such as copying machines, such as photosensitivity, thermal stability, moisture resistance, and durability.

For example, a selenium photoreceptor crystallizes due to heat or fingerprint stains when touched, so the above-mentioned characteristics required for an electrophotographic photoreceptor tend to deteriorate.

Further, electrophotographic photoreceptors using cadmium sulfide have poor moisture resistance and durability, and electrophotographic photoreceptors using zinc oxide have problems with durability such as film strength.

Furthermore, since selenium and cadmium sulfide are toxic, there are significant restrictions in manufacturing and handling.

In recent years, in order to eliminate the drawbacks of photoreceptors using these inorganic materials, electrophotographic photoreceptors using various organic materials have been researched and developed, and some of them have been put into practical use. For example, poly
N-vinylcarbazole and 2, 4. 7-1-IJ nitrofluoren-9-one electrophotographic photoreceptor (
U.S. Pat. JP-A-47-1.0785) and an electrophotographic photoreceptor whose main component is a eutectic complex consisting of a dye and a resin.

However, although these photoreceptors have improved the drawbacks of the inorganic photoreceptors to some extent, they generally have low photosensitivity, are not suitable for repeated use, and do not fully meet the requirements as electrophotographic photoreceptors.

In order to improve these shortcomings, an electrophotographic photoreceptor with a functionally separated photoconductive layer in which the charge generation function and charge transport function are assigned to different materials was proposed, and it has become the mainstream of current research. It has become.

Functionally separated electrophotographic photoreceptors expand the range of material selection,
Along with this, it is possible to improve the characteristics such as sensitivity and durability of the electrophotographic photoreceptor, and it has the advantage that materials suitable for forming the coating film of the electrophotographic photoreceptor can be selected from a wide range.

Various organic dyes and pigments have been developed as effective organic charge generating substances used in the charge generating layer of such functionally separated electrophotographic photoreceptors, such as azo pigments with various structures, perylene pigments, etc. Pigments, polycyclic bovine non-based pigments, square methine dyes, etc. are used.

However, although these pigments show relatively good sensitivity in the short or medium wavelength range, their sensitivity in the long wavelength range is low, making them difficult to use in laser printers that use semiconductor laser light sources that are expected to have high multipliers. It was difficult.

"Problem to be solved by the invention" The oscillation wavelength of gallium-aluminum-arsenide light-emitting devices, which are currently widely used as semiconductor lasers, is 75
It is 0 nm or more. Many studies have been made in the past in order to obtain electrophotographic photoreceptors that are highly sensitive to such long wavelength light. For example, Se, Cd, which has high sensitivity in the visible light region
A method has been considered in which a sensitizer is added to a photosensitive material such as S to increase the wavelength, but as mentioned above, Se and CdS do not have sufficient environmental resistance against temperature, humidity, etc.

Furthermore, as mentioned above, the sensitivity of many known organic photoconductive materials is usually limited to the visible light region of 700 nm or less, and there are few materials that have sufficient sensitivity in longer wavelength regions.

Among these, phthalocyanine compounds, which are one of the organic photoconductive materials, are known to have a sensitivity range expanded to longer wavelengths compared to the pigments and dyes mentioned above. There are deficiencies in electrophotographic properties such as gender. In order to improve these drawbacks, phthalocyanines with various changes in the central metal or various crystal forms have been developed. Various crystalline forms of phthalocyanine have been discovered through the process of converting unstable α-type phthalocyanine into stable β-type crystalline form. For example, ε-type copper phthalocyanine,
M-type metal-free phthalocyanine and m-type titanyl phthalocyanine are known. These phthalocyanines have sensitivity in the long wavelength range, but the sensitivity is insufficient for use in copiers or optical printers, and furthermore, in repeated use,
It had drawbacks such as insufficient potential stability and large residual potential, and could not be put to practical use.

On the other hand, methods for improving the sensitivity of electrophotographic photoreceptors containing phthalocyanine pigments include adding charge-transporting compounds such as hydrazine compounds and oxazole compounds, or adding electron-withdrawing compounds such as tetranitrofluorene and trinitrofluorene. However, although some exacerbating effects have been observed, the effects may not be sufficient, or these additives may cause a decrease in chargeability, a decrease in potential stability during repeated use, a decrease in sensitivity, Adverse effects such as an increase in residual potential were observed, and none of them were suitable for practical use. Furthermore, the electron-withdrawing compound is toxic and cannot be put to practical use.

By the way, in general, in electrophotographic photoreceptors, a charge transporting material that is effective for a particular charge-generating substance is not necessarily effective for other charge-generating substances; It cannot be said that a charge-generating substance that is effective against other charge-transporting substances is also effective against other charge-transporting substances.

In this way, an appropriate combination of charge-generating substances and charge-transporting substances is required, and regarding this combination,
Although some regularity can be seen, it does not apply to all substances.

For example, a charge transport material combined with a charge generating material'
It has been proposed to use ionization potential as a guideline for t'A, but these results are for specific similar materials, lack -g properties, and do not clearly explain the electrophotographic characteristics between different materials. It has not yet reached that point.

As described above, the current situation is that various combinations of charge-generating materials and charge-transporting materials have been studied through trial and error.

As you can see from the above, high sensitivity, especially 75Qnr
It has been desired to develop an electrophotographic photoreceptor that is highly sensitive to light with a long wavelength of n or more, has high potential stability during repeated use, and has little reduction in residual potential and sensitivity.

"Objective of the Invention" The object of the present invention is to have high sensitivity, especially sufficient sensitivity to long-wavelength light such as semiconductor lasers, high potential stability, low residual potential, and durability during repeated use. The purpose of the present invention is to provide a high quality electrophotographic photoreceptor.

"Means for solving the problem" As a result of intensive research, we discovered that compounds represented by general formulas (r) to (V[) sensitize phthalocyanine pigments, and furthermore, we discovered that compounds represented by general formulas (r) to (V[) sensitize phthalocyanine pigments and general formulas ( I)～(
The photoreceptor using the compound represented by VI) and the compound represented by the general formula (VII) has excellent potential stability and residual potential characteristics during repeated use compared to photoreceptors using other pigments. They discovered this and arrived at the present invention.

General formula (1) General formula (In) General formula (IV) Z General formula (V) General formula (Vl) General formula (■) In general formulas (1) to (■), 2 represents a sulfur atom or an oxygen atom. represent.

R1, R2, R3, R4, R5, and R6 each represent a hydrogen atom, an alkyl group, an aryl group, or a monovalent group derived from a heterocycle, and may be the same or different from each other, RI
and R2, or R1 and R4 may each be connected. In general formula (1), R', R'', R3, R'
may be linked together to form a bridged ring as a whole. R
' represents a divalent arylene group, aralkylene group, polymethylene group or alkylene group.

R11 is an alkyl group, an alkoxy group, a monocyclic or bicyclic aryl group, or a monocyclic or bicyclic aryl group.
represents a monovalent group derived from a fluoroxy group or a heterocyclic ring. In general formula (V), two R3s may be the same or different.

R9 and RIO represent an alkyl group, an aryl group, or an aralkyl group, and R9 and RIO may be the same or different groups.

Rl 1 represents a hydrogen atom, an alkyl group, an aralkyl group, or an aralkyl group. Furthermore, Ar and R11 may form a ring.

R-1 and R'' represent an alkyl group, an aralkyl group, or an aryl group, R'! and R1'' may be the same or different from each other, and R'1 and RI3 may form a heterocycle.

R14 represents a hydrogen atom, an alkyl group, or an aryl group.

Ar+ and Arz represent a monovalent aromatic hydrocarbon group or a monovalent heterocyclic group.

n represents an integer of O or 1.

That is, the present invention provides: (1) An electrophotographic photoreceptor in which a photoconductive layer is provided on a conductive support, in which the photoconductive layer comprises a) a phthalocyanine pigment, b)
-11G formula (Vl) and at least one compound represented by general formula (VII). Angry light body.

(2) The light source of the copying machine and the optical printer is a laser beam, f1. According to the present invention, the electrophotographic photoreceptor has high sensitivity and exhibits good characteristics in repeated use. A highly durable electrophotographic photoreceptor can be obtained.

(Specific structure and effects of the present invention) Phthalocyanine pigments used in the photoconductive layer of the electrophotographic photoreceptor of the present invention include those with different central metals, those with different crystal shapes, and those with a substituent on the benzene ring. Such,
A wide variety of phthalocyanine pigments can be used. For example, Special Publication No. 44-14106, Special Publication No. 45-8102
, Special Publication No. 46-42511. Tokuko Sho 46-42512,
Metal-free phthalocyanine described in Japanese Patent Publication No. 49-4338, Japanese Patent Application Publication No. 58-182639, Japanese Patent Application Publication No. 62-47054, etc.; Japanese Patent Publication No. 1973-'95852
, JP-A-51-108847, JP-A-51-10984
Copper phthalocyanine described in No. 1, JP-A-59-49544
．． JP-A-59-166959, JP-A-62-27527
2. Japanese Patent Publication No. 62-286059, Japanese Patent Application Publication No. 62-6709
4, JP-A-63-364, JP-A-63-365, JP-A-63-37163, JP-A-63-57670, JP-A-6
3-80263, JP-A-63-116158, JP-A-6
titanyl phthalocyanine described in 3-198067 etc.,
JP-A-57-90058, JP-A-62-163060,
Japanese Patent Publication No. 1987-133462, Japanese Patent Publication No. 62-17706
9, JP-A-63-73529, JP-A-63-43155
Aluminum phthalocyanine, described in JP-A-57-
146255, JP-A-57-147641, JP-A-57
-148747 etc., JP-A-59-44053, JP-A-59-128544, JP-A-59-133550, JP-A-59-133551,
JP-A-59-174846, JP-A-59-174847
, JP-A-60-59354, JP-A-60-560054
, JP-A-60-220958, JP-A-62-22925
4, JP-A-63-17457, JP-A-59-15585
Examples include, but are not limited to, halogenated metal phthalocyanines described in JP-A-63-27562 and JP-A-63-56564, etc., but are not limited thereto (although various known phthalocyanines can be used).

Typical core metals of phthalocyanine include metals such as copper, nickel, iron, vanadium, aluminum, gallium, indium, silicon, titanium, magnesium, cobalt, platinum, and germanium, as well as various metal-free phthalocyanines. It is being

The crystal form is confirmed by crystal diffraction (for each metal phthalocyanine and metal-free phthalocyanine),
For example, in copper phthalocyanine, α type, β type, τ type, δ type
Metal-free phthalocyanine has α-type, β-type, χ-type, τ-type and other polymorphisms; and titanyl phthalocyanine has α-type, β-type, β-type, etc. M-type and other polymorphisms are known. Furthermore, substituted phthalocyanines in which the benzene ring of phthalocyanine is substituted with a halogen atom such as fluorine, chlorine, or bromine, an alkyl group, a carboxyl group, an amide group, a sulfonyl group, or other substituents are also known.

Furthermore, the phthalocyanine pigments used in the present invention include:
JP-A-63-233886, JP-A-63-18625
Germanium naphthalocyanine as described in JP-A-63-55556, JP-A-63-141070, etc., silicon naphculocyanine as described in JP-A-63-186251, Kaisho 64-20
Tin naphthalocyanine described in No. 61 etc., JP-A-63-
Various metal naphthalocyanines described in JP-A-63-231355 and the like can also be mentioned.

These have different absorption wavelengths and are used as appropriate depending on the application, but when used in a laser beam printer etc. that uses a semiconductor laser as a light source, 780 n'
Preferred are phthalocyanine pigments that exhibit absorption in the wavelength range from m to 830 nm.

Next, compounds represented by formulas (1) to (VI) that improve the photoconductivity of a photoconductive layer using a phthalocyanine pigment will be explained.

In general formulas (I) to (VI), Z represents a sulfur atom or an oxygen atom.

When any of R1, R1, Rff, R4, R5, and R6 is an alkyl group, examples of the alkyl group include linear or branched unsubstituted or substituted alkyl groups having 1 to 22 carbon atoms.

Examples of substituent A groups bonded to alkyl groups include halogen atoms (chlorine atom, bromine atom, fluorine atom), cyano group, nitro group, phenyl group, tolyl group, and trifluoromethyl group, and the number of substituents is The number is 1 to 3.

When any of R1, Rg, R3, RJ, R5, and R6 is an aryl group, examples of the aryl group include a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, and a substituted or unsubstituted anthranyl group. . Substituents include halogen atom (chlorine atom, bromine atom, fluorine atom), cyano group, nitro group, trifluoromethyl group, carbon atom number 1
Substituted with 1 to 3 linear or branched alkyl groups, carboxyl groups, alkoxycarbonyl groups, cyano groups, nitro groups, or halogen atoms (chlorine atoms, bromine atoms, fluorine atoms) ranging from 5 to 5 (2 or 3 substitutions, they may be the same or different from each other,
) Straight-chain or branched alkyl groups having 1 to 5 carbon atoms, straight-chain or branched alkoxy groups having 1 to 5 carbon atoms, and the number of substituents ranges from 1 to 5. If there are 3 substituents and 2 or 3 substituents, they may be the same or different from each other.

When any of R1, R1, R), R4, R5, and R6 is a monovalent group derived from a heterocycle, a substituted or unsubstituted pyrrolidinyl group, piperidinyl group, piperidino group, morpholinyl group, morpholino group, pyrrolyl group , imidazolyl group, pyridyl group, pyrimidinyl group, indolinyl group, isoindolinyl group, indolyl group, isoindolyl group,
Benzimidazolyl group, quinolyl group, isoquinolyl group, etc., and substituents thereof include halogen atom (chlorine atom, bromine atom, fluorine atom), cyan group, nitro group, trifluoromethyl group, phenyl group, tolyl group, benzyl group,
Phenethyl group, substituted with 1 to 3 linear or branched alkyl groups having 1 to 5 carbon atoms (if 2 or 3 substituents are bonded, the substituents may be the same) may be different.)l (11i group is mentioned.

When R1 and R4 or R1 and R4 are connected, examples include trimethylene group, tetramethylene group, pentamethylene group, oxydiethylene group (CH2CH
I OCHI CHz ), and 1 to 3 hydrogen atoms of these divalent groups are halogen atoms (chlorine atom, bromine atom, fluorine atom), cyano group, nitro group, phenyl group, tolyl group, benzyl group, phenethyl group and a divalent group substituted with a linear or branched alkyl group having 1 to 5 carbon atoms. Further, the component of these divalent groups may be a part of an aryl ring or a heterocycle.

When R7 is a divalent arylene group, a specific example is p
-phenylene group, m-phenylene group, 0-phenylene group, 1,4-naphthylene L2.3-naphthylene group, 4,4
'-biferrylene group is mentioned. Examples of polymethylene groups include polymethylene groups having 1 to 22 carbon atoms. In the case of alkylene group, propylene group, butylene group, pentylidene group, 1,2-dimethylethylene group, ■.

3-dimethyltrimethylene group, 1,4-dimethyltetramethylene group, 1.5-dimethylpentamethylene group, 1.
6-dimethylhexamethylene group, 1-ethylethylene L
Examples include l,2-diethylethylene group.

The arylene group and the aralkylene group may be substituted with a substituent. Examples of the substituent include a halogen atom, a cyano group, a nitro group, a trifluoromethyl group, and an alkyl group having 1 to 5 carbon atoms. .

When R8 is an unsubstituted or substituted monovalent group derived from an alkyl group, aryl group, or heterocycle, R8 is an unsubstituted or substituted monovalent group derived from an unsubstituted or substituted alkyl group, aryl group, or heterocycle of R'. Represents a group similar to a monovalent group.

When R6 is an alkoxy group or a substituted alkoxy group, examples thereof include the aforementioned alkyl group or an alkoxy group having a substituted alkyl group or a substituted alkoxy group.

When R8 is a substituted or unsubstituted monocyclic or bicyclic aryloxy group, examples thereof include the above-mentioned substituted or unsubstituted monocyclic or bicyclic fused aryloxy group having two aryl groups. can.

R9 and RIG represent an alkyl group that may have a substituent, an aralkyl group that may have a substituent, or an aralkyl group that may have a substituent. When these groups are substituted, the substituents include alkyl groups,
Cyano group, hydroxy group, carboxyl group, nitro group,
Halogen atoms such as chlorine, fluorine, and bromine, amino groups, alkoxy groups, aryl groups, aryloxy groups, alkoxycarbonyl groups, acyloxy groups, alkyl groups, amino groups substituted with aryl groups, or aralkyl groups, trifluoromethyl groups, etc. can be given.

Specific examples of R9 and R16 include methyl group, ethyl group,
n-propyl group, 1so-propyl group, n-butyl group,
Straight chain alkyl groups such as 5ec-butyl group, n-hexyl group, 2-ethylhexyl group, fluoromethyl group, chloromethyl group, trifluoromethyl group, perfluoroalkyl group, methoxymethyl group, cyanomethyl group, branched alkyl group, substituted alkyl group, phenyl group, p-1
-Lifluoromethylphenyl group, 0-trifluoromethylphenyl group, p-cyanophenyl group, 0-cyanophenyl group, p-nitrophenyl group, O-nitrophenyl L
p-bromophenyl group, o-bromophenyl group, p-chlorophenyl group, O-chlorophenyl L p-fluorophenyl group, 0-fluorophenyl group, N, N-dimethylamide group, N.

N-diethylamide group, p-carboxylphenyl group,
p-methoxyphenyl group, 0-methoxyphenyl) I4,
N,N-diethylaminophenyl group, N,N-diphenylaminophenyl group, N,N-dibenzylaminophenyl group, N,N-dimethylphenyl group, naphthyl group, methoxynaphthyl group, N,N-diethylaminonaphthyl group, Hensyl group, p-bromobenzyl L p-cyanobenzyl group, p-nitrobenzyl group, p-trifluoromethylhensyl group, 0-bromobenzyl group, 0-cyanobenzyl group, 0-nitrobenzyl group, phenylethyl group ,3
-Phenylpropyl L Examples include aryl groups such as p-chlorobenzyl group and naphthylmethyl group, substituent aryl group, aralkyl group, and substituted aralkyl group. Rq
and R'' may be the same or different groups.

R1 represents a hydrogen atom, an alkyl group that may have a substituent, an aryl group that may have a substituent, or an aralkyl group that may have a substituent. Examples of substituents when an alkyl group, aryl group or aralkyl group is substituted include the same substituents listed as the substituents for R9 and R16.

Specific examples of R9 and R'' include a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, a so-propyl group,
n-butyl group, 5ec-butyl group, n-hexyl group, 2
-ethylhexyl group, fluoromethyl group, chloromethyl group, trifluoromethyl group, perfluoroalkyl group,
Linear alkyl groups, branched alkyl groups, substituted alkyl groups such as methoxymethyl group and cyazmedel group, phenyl group, p-trifluoromethylphenyl group, o-trifluoromethylphenyl group, p-cyanophenyl group, 0
-cyanophenyl group, p-nitrophenyl group, 0-nitrophenyl group, p-bromophenyl l, o-bromophenyl group, p-chlorophenyl group, o-chlorophenyl group, p-fluorophenyl%, o-fluoro phenyl group,
N,N-dimethylamide group, N,N-diethylamide group, p-carboxylphenyl group, p-methoxyphenyl group, 0-methoxyphenyl M, N,N-diethylaminophenyl group, N,N-diphenylaminophenyl group, N
.

N-dibenzylaminophenyl group, N,N-dimethylaminophenyl group, naphthyl group, methoxynaphthyl group, cyanonaphthyl group, nitronaphthyl group, chloronaphthyl group, bromonaphthyl group, fluoronaphthyl group, trifluoromethylnaphthyl group, N.

N-diethylaminonaphthyl group, benzyl group, phenylethyl group, 3-phenylpropyl group, p-chlorobenzyl! , p-bromobenzyl Lp-cyanobenzyl group, p
-Nitrobenzyl group, p-trifluoromethylbenzyl group, O-bromobenzyl group, o-cyanobenzyl group, o
Examples include aryl groups such as -nitrobenzyl group and naphthylmethyl group, substituent aryl groups, aralkyl groups, and substituted aralkyl groups.

Ar represents a monovalent aromatic hydrocarbon group which may have a substituent or a monovalent heterocyclic group which may have a ttA group. In this case, the aromatic hydrocarbon group or heterocyclic group includes phenyl group, naphthyl group, anthranyl group, furan, virol, thiophene, indole, benzofuran, benzothiofuran, oxazole, imidazole, thiazole, isoxazole, pyridine, Quinoline, isoquinoline, pyridazine, pyrimidine, pyrazine, phthalazine and derivatives thereof, such as 2
-thio-4-thiazolidinone, 3-pyrazolidinone, 5
-isoxacilone, 2-oxazolidone, 2,4-thiazolidinedione, 2-thiophenone, 2-furanone,
Examples include 4-pyrimidone. When these have substituents, the substituents include methyl group, ethyl group, n-
Propyl group, tso-propyl group, n-butyl group, 5e
c-butyl group, n-hexyl group, 2-ethylhexyl group, fluoromethyl group, chloromethyl group, trifluoromethyl group, perfluoroalkyl group, methoxymethyl group,
Straight chain alkyl groups, branched alkyl groups, substituted alkyl groups such as cyanmethyl group, and Fe=/L4, p-trifluoromethylphenyl4.

-cyanophenyl group, p-nitrophenyl group, p-bromophenyl Lo--y romophenyl group.

-Chlorphenyl L p-fluorophenyl group, p-methoxyphenyl group, N,N-diethylamilafnyl method,
N,N-dimethylaminophenyl group, naphthyl group, methoxynaphthyl group, cyanonaphthyl group, chloronaphthyl group, benzyl group, phenylethyl group, 3-phenylpropyl group, p-chlorohensyl Lp-cyanobenzyl group, p
-Nitrobenzyl group, p-4-lifluoromethylbenzyl group, 0-bromobenzyl group, 0-cyanobenzyl group, 0
- Aryl groups such as nitrobenzyl groups and naphthylmethyl groups, substituted aryl groups, aralkyl groups, substituted aralkyl groups, cyano groups, hydroxy groups, carboxyl groups, nitro groups, halogen atoms such as chlorine, fluorine, and bromine, -NHCO
R'? The group (R") represented by represents a substituted or unsubstituted alkyl group, aryl group, or aralkyl group), -N
H3OzR+7 (R” has the same meaning as above), SOR” (R
'7 has the same meaning as above), -3O2R"(R'7 has the same meaning as above), -COR"(R' has the same meaning as above), which may be different, hydrogen atom, substituted or unsubstituted alkyl group, aryl group, aralkyl group), sulfonic acid group, amino group, alkoxy group, aryl group, aryloxy group, alkoxycarbonyl group, acyloxy group, alkyl group or amino group substituted with an aryl group or aralkyl group, and amides group, trifluoromethyl group, etc. As these substituents, electron-withdrawing substituents are preferably used rather than hydrogen atoms.

Next, the compound represented by the general formula [■] will be explained in more detail.

R12 and R1ff each represent an unsubstituted or substituted alkyl group having 1 to 12 carbon atoms, an unsubstituted or substituted aralkyl group having 7 to 20 carbon atoms, or an unsubstituted or substituted aryl group. The expressions RIz and R11 may be the same or different.

When RIZ and Rhi are unsubstituted alkyl groups, specific examples include methyl group, ethyl group, propyl group, butyl group,
Pentyl group, hexyl group, isopropyl group, isobutyl group, isoamyl group, isohexyl group, neopentyl group,
Examples include tar t-butyl group.

When RIZ, R''' is a substituted alkyl group, the substituent includes a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, a cyano group, an amino group, an alkylamino group having 1 to 12 carbon atoms,
Examples include a dialkylamino group having two alkyl groups having 1 to 12 carbon atoms, a halogen atom, and an aryl group having 6 to 5 carbon atoms. Examples include hydroxyalkyl groups (e.g. hydroxymethyl group, 2-hydroxyethyl group, 3-hydroxyethyl group,
-hydroxypropyl group, 2-hydroxypropyl group, etc.), alkoxyalkyl group (e.g., methoxymethyl group, 2-methoxyethyl group, 3-methquinepropyl group, ethoxymethyl group, 2-ethoxyethyl group, etc.), cyanoalkyl group groups (e.g., cyanomethyl group, 2-cyanoethyl group, etc.), aminoalkyl groups (e.g., aminomethyl group,
2-aminoethyl group, 3-aminopropyl group, etc.), (alkylamino)alkyl group (e.g. (methylamino)
Methyl! , 2<methylamino)ethyl group, (ethylamino)methyl group, etc.), (dialkylamino)alkyl group (e.g., (dimethylamino)methyl group, 2-(dimethylamino)ethyl group, etc.), halogenoalkyl group (e.g. , fluoromethyl group, chloromethyl group, bromomethyl group, etc.), and aralkyl groups (eg, benzyl group, phenethyl group, etc.).

When RIZ and R1 are unsubstituted aralkyl groups, specific examples thereof include benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-anthrylmethyl group, and benzhydryl group.

In the case of an aralkyl group having a substituent, specific examples of the substituent include the substituent when R1 is a substituted alkyl group, and any of these substituents is present on any carbon atom of the aralkyl group. (Both are examples of aralkyl groups in which one bonded aralkyl group has a substituent.

When Rlm and RIS are unsubstituted aryl groups, specific examples thereof include phenyl, l-naphthyl, 2-naphthyl, anthryl, pyrenyl, and acenaphthynyl groups. In the case of an unsubstituted aryl group, specific examples of substituents include the above-mentioned substituents when Rlm and R13 are substituted alkyl groups, and other alkyl groups include methyl group, ethyl group, propyl group, butyl group. , pentyl group, isopropyl group, isobutyl group, isopentyl group,
Any of these substituents is an example of an aryl group in which at least one aryl group bonded to a carbon atom of the above-mentioned aryl group has a substituent.

An example of the heterocycle formed by R12 and R13 is a fluorenyl group.

Specific examples of R'4 include a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, etc.), and a ryol group with or without a substituent. The aryl group having a substituent is the same as the aryl group having a substituent represented by R12 and R'' described above.

Arz is an aromatic hydrocarbon group such as phenyl, naphthyl, anthryl, 2-furyl group, 2-chenyl group, l
-Methyl-2-pyrrolyl group, 5-methyl-2-chenyl group, 2-pyridyl group, 2-benzo(b)chenyl group, 2
-naphtho(2,3-b)chenyl group, 9-ethylcarbazol-2-yl group, dibenzothiophen-2-yl L
It represents a heterocyclic group such as a 2-phenoxathiinyl group, a 10-ethylphenoxazin-3-yl group, and a 10-ethylphenothiazin-3-yl group.

These may have a substituent, and examples of the substituent include an alkyl group, an alkoxy group, and an amino group.

Specific examples of the Zta group of Ar are groups having 1 to 1 carbon atoms such as methyl group, ethyl group, propyl group, butyl group, hexyl group, etc.
2 alkyl groups, and alkoxy groups or aralkyloxy groups include alkoxy groups having 1 to 12 carbon atoms and 7ralkyloxy groups having 1 to 12 carbon atoms, and specific examples thereof include methoxy groups, ethoxy groups, propoxy groups, There are butoxy, octyloxy, and benzyloxy groups.

In the case of substituted amino groups, RIS and RI6 are alkyl groups having 1 to 12 carbon atoms without substituents such as methyl group, ethyl group, propyl group, butyl group, or 1 to 12 carbon atoms having substituents as shown below. ~12 alkyl groups, substituted or substituted phenyl groups, and RIS and R'' may be connected to form a heterocycle.

Substituents for the alkyl group having a substituent represented by RIS and R1'' include an alkoxy group having 1 to 4 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, a hydroxy group, an aryl group having 6 to 12 carbon atoms, and a cyano group. groups and halogen atoms.

Specific examples of alkyl groups having substituents represented by Ras and RI6 include alkoxyalkyl groups (e.g., methoxymethyl group, methoxyethyl group, ethoxymethyl group, ethoxyethyl group, ethoxypropyl group, methoxybutyl group, propoxymethyl group) etc.), aryloxyalkyl groups (e.g. phenoxymethyl group, phenoxyethyl group, naphthoxymethyl group, phenoxypentyl group, etc.)
, hydroxyalkyl group (e.g. hydroxymethyl group,
hydroxyethyl group, hydroxypropyl group, hydroxyoctyl group, etc.), aralkyl group (e.g., benzyl group, phenethyl group, ω, ω-diphenylalkyl group, etc.),
Preferred are cyanoalkyl groups (eg, cyanomethyl, cyanoethyl, cyanopropyl, cyanobutyl, etc.), heroal groups (eg, chloromethyl, bromomethyl, chloroethyl, bromopentyl, chlorooctyl, etc.).

The phenyl group represented by RI5 and R16 may have a substituent, and specific examples of the substituent in the case of a phenyl group having a substituent include an alkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms, -4 alkoxy group, C6-7 aryloxy group, C2-8 acyl group, C2-5
alkoxycarbonyl group, halogen atom, carbon number 1-
Examples include a monoalkylamino group substituted with an alkyl group having 4 carbon atoms, a dialkylamino group substituted with an alkyl group having 1 to 4 carbon atoms, an amide group having 2 to 4 carbon atoms, and a nitro group.

As an alkyl group having 1 to 12 carbon atoms, a methyl group, an ethyl group, a linear or branched propyl group, a butyl group, a pentyl group, a hexyl group, as an alkoxy group having 1 to 4 carbon atoms, a methoxy group, an ethoxy group, Propoxy group, butoxy group, phenoxy group, 0-lm- or p-tolyloxy group as aryloxy group, acetyl group, propionyl group, benzoyl group, 0-lm- or p-tolyloxy group as acyl group
- toluoyl group, alkoxycarbonyl group having 2 to 5 carbon atoms as methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, butoxycarbonyl group, halogen atom as chlorine atom, bromine atom, fluorine atom,
As a monoalkylamino group substituted with an alkyl group having 1 to 4 carbon atoms, a methylamino group, an ethylamino group,
Dimethylamino group, diethylamino group, dipropylamino group, dibdelamino group, N-methyl-N-ethylamino group as a butylamino group, dialkylamino group substituted with a C1-C4 alkyl group, acetamido group as an amide group , a propionamide group, and other substituents include a nitro group.

Alternatively, RI5 and R1'' may be connected to form a heterocycle, and examples of the heterocycle in this case include a pyrrolidine ring, a morpholino ring, an N-methylpiperazino ring, and a julolidino ring.

Next, specific examples of the metal compounds represented by the above general formulas (I) to (VI) are shown below, but the present invention is not limited to these compounds.

Exemplary Compound 1 Exemplified Compound 2 Exemplified Compound 3 Exemplified Compound 4 Exemplified Compound 5 Exemplified Compound 6 Exemplified Compound 7 Exemplified Compound 8 Exemplified Compound 9 011″V-″ Exemplified Compound 10 Exemplified Compound 11 Exemplified Compound 12 Exemplified Compound 13 Exemplified Compound 14 Exemplified Compound 15 Exemplary compound 16 Exemplified compound 17 Exemplified compound 18 Exemplified compound 19 Exemplified compound 20 Exemplified compound 21 Exemplified compound 22 Exemplified compound 23 Exemplified compound 24 Exemplified compound 25 Exemplified compound 26 Exemplified compound 27 Exemplified compound 28 Exemplified compound 29 Exemplified compound 30 Exemplified compound 31 Exemplified compound 33 Exemplary Compound 34 Exemplified Compound 35 Exemplified Compound 36 Exemplified Compound 37 Exemplified Compound 38 Exemplified Compound 39 Exemplified Compound 40 Exemplified Compound 41 Exemplified Compound 42 Exemplified Compound 43 Exemplary compound 49 Exemplary compound 50 Exemplary compound 51 Exemplary compound 52 Exemplified compound 53 Exemplified compound 54 Exemplified compound 56 Exemplified compound 57 Exemplified compound 58 Exemplified compound 59 Exemplified compound 60 Exemplified compound 61 Exemplified compound 62 Exemplified compound 63 Exemplified compound 64 Exemplified compound 65 Exemplified compound 66 Exemplary Compound 67 Next, specific examples of the compound represented by the general formula (VII) are shown below.

Exemplary compound 68 Exemplary compound 69 Exemplary compound 70 Exemplary compound 71 Exemplary compound 72 Exemplary compound 73 Exemplary compound 74 Exemplary compound 75 t Exemplary compound 76 Exemplary compound 77 Exemplary compound 78 Exemplary compound 79 Exemplary compound 80 Exemplary compound 82 Exemplary compound 82 General in the present invention The urea and thiourea compounds represented by formula (1) or general formula (II) are all rJ, chem
, soc, j 1955.1573-1581.

Further, the amide and thioamide compounds represented by general formulas (III) to (V) are all rBe1lsteins1
1andbuchder Organchen Ch
It can be easily synthesized by the method described in emteJ, Vol. 12, p. 262.

Furthermore, the (thio)barbic acid compound represented by the general formula (Vr) is
Xnoeve described in J Vol. 15, pp. 204-599
na((el) By the condensation method, the corresponding aldehyde or ketone and barbylic acid or thiobarbylic acid are combined with an alkali (e.g., NaOH, KOH, annimore,
It can be easily produced by dehydration condensation using an amine (eg, diethylamine, triethylamine, piperidine, etc.) as a catalyst.

Furthermore, the hydrazone compound represented by the -a formula (VII) can be easily synthesized by the method described in Japanese Patent Publication No. 60-34099.

It is known that electrophotographic photoreceptors using phthalocyanine pigments exhibit an induction effect that causes a delay in the attenuation of the surface potential immediately after irradiation with light, which causes a decrease in sensitivity. The reason for this is not clear, but it is thought that there are carrier traps on the surface of the phthalocyanine particles, and carriers generated by light irradiation are captured by these carrier traps, so that no attenuation of the surface potential is observed during this period. It is being The compounds of the present invention are considered to be sensitizers that reduce this induction effect, shorten the time during which the surface potential does not decay (induction period), and improve sensitivity as a result.

General formula (+) ~ (VT
The use of the compound represented by
No. 2239, No. 58-102240, JP-A-58-6
No. 5438, No. 58-65439, JP-A No. 56-14
This is described in No. 9462 and No. 57-29650.

However, these patents claim to be invented as sensitizers for further sensitizing dye-sensitized organic photoconductors, and are not intended to be used as sensitizers for photoconductors that have not been dye-sensitized like the present invention. Sensitivity effects are not listed. Furthermore, the above specification does not describe the use of a phthalocyanine pigment as a photoconductive pigment in the present invention. Regarding the use of photoconductive pigments, Z
Although there is a description of using nO, these are only known to be effective when an inorganic photoconductor such as ZnO is dye-sensitized, and are unique to phthalocyanine pigments as in the present invention. It was completely unexpected that this method would have the effect of reducing the induction effect.

Also, JP-A-58-102239, JP-A No. 58-I0224
No. 0, JP-A-58-65438, JP-A No. 58-65439
No., JP-A-56-149462, JP-A No. 57-29650
The electrophotographic photoreceptor described in the above issue exhibits good electrophotographic properties when used only once, but when used repeatedly several times, it causes a significant decrease in charging potential, decrease in sensitivity, and increase in residual potential. It cannot be used as a photoreceptor for copiers and optical printers that are used repeatedly.

In addition, when various additives such as tetranitrofluorene, tetracyanoethylene, and other electron-withdrawing compounds are added to increase the sensitivity of phthalocyanine, the chargeability decreases, and upon repeated use, the charging potential decreases and the residual potential increases. occurs.

However, the compounds represented by the general formulas (I) to (VI) of the present invention do not cause deterioration of the above-mentioned repeatability characteristics and sensitize phthalocyanine, so they are required to have high exasperation and good repeatability characteristics. Suitable for use in photoconductors for copying machines and optical printers.

The electrophotographic photoreceptor of the present invention has a photoconductive layer containing the aforementioned phthalocyanine pigment, at least one of the compounds represented by formulas (I) to (VI), and a compound represented by formula (VII).

Various types of electrophotographic photoreceptors are known, but
The electrophotographic photoreceptor of the present invention may be any type of photoreceptor. Generally, the electrophotographic photoreceptor of the present invention is used with the type of layer structure exemplified below.

(1) A phthalocyanine pigment and a type of compound represented by general formulas (I) to (VI) on a conductive support,
and a single photoconductive layer containing a compound represented by general formula (VII).

(2) Phthalocyanine pigment and general formula (
1) A charge generation layer containing a compound represented by formula (Vr) is provided, and a charge transport layer containing a compound represented by general formula (VII) is provided thereon.

(3) A charge transport layer containing a compound represented by general formula (VII) is provided on a conductive support, and a charge transport layer containing a phthalocyanine pigment and a compound represented by general formulas (I) to (VI) is provided thereon. A generation layer is provided.

In order to produce an electrophotographic photoreceptor of type (1), compounds represented by general formulas (1) to (VT) and general formula (VI
A phthalocyanine pigment may be dispersed in a solution in which the compound represented by I) and a binder are dissolved, and this may be applied onto a conductive support and dried. Alternatively, a coating liquid may be prepared by dispersing the phthalocyanine pigment in a binder solution, and then dissolving the compounds represented by general formulas (1) to (VT) and the compound represented by general formula (VII) in this solution. .

The thickness of the photoconductive layer at this time is 3 to 50μ, preferably 5 to 50μ.
30μ is good.

To create an electrophotographic photoreceptor of type (2), first, phthalocyanine and general formulas (1) to
A charge generating layer is provided by dispersing the compound represented by ('/I) in a suitable solvent or, if necessary, in a solvent in which a binder is dissolved, and then coating and drying. Alternatively, a coating liquid may be prepared by dispersing a phthalocyanine pigment in a solvent or a solvent in which a binder is dissolved, and then dissolving a compound represented by a compound represented by formulas (1) to (V[). . Thereafter, a solution containing a charge transport compound represented by the general formula (VII) and a binder is applied thereon and dried to provide a charge transport layer. The thickness of the charge generation layer at this time is 4μ or less, especially 0.1
The thickness of the charge transport layer is preferably 3 to 50 microns, particularly preferably 5 to 30 microns.

Further, in the charge generation layer of the present invention, a thin layer containing a compound represented by one of the general formulas (I) to (VI) is provided between the charge generation layer and the conductive support, and a A method in which a charge generation layer of a phthalocyanine pigment is provided by vapor deposition, and a phthalocyanine pigment and a compound represented by the general formulas (+) to (Vl) are formed by diffusion of an upper layer coating solvent, or a charge generation layer of a phthalocyanine pigment is formed on a conductive support. It can be produced by depositing a pigment, applying thereon a solution containing a compound represented by the general formulas (+) to (Vl), and allowing it to coexist with a phthalocyanine pigment. In this case, the thickness of the phthalocyanine pigment deposited is 0.001μ~
1μ, especially 0.01μ to 0.5μ is preferred.

The electrophotographic photoreceptor of type (3) is produced by reversing the stacking order of the charge generation layer and charge transport layer of type (2).

The type (1) photoreceptor of the present invention has relatively good repeating characteristics because the phthalocyanine itself has a charge transfer ability compared to azo pigments, etc.;
) and (3), the sensitivity is low, and the decrease in charging potential and increase in residual potential due to repeated use are also somewhat large.

Therefore, types (2) and (3) are preferred as usage forms of the present invention, and in this form, they have extremely high sensitivity, little change in charging potential in repeated use, low residual potential, high rigidity resistance, A highly durable electrophotographic photoreceptor can be obtained.

(The phthalocyanine pigment used in the photoreceptors of types 11+21 and (3) is pulverized and dispersed using a known dispersing machine such as a ball mill, sand mill, vibration mill, etc., but the particle size of the phthalocyanine is preferably 5μ or less, 0.
It is used after being ground to 1 to 2 microns.

If the amount of phthalocyanine pigment used in the electrophotographic photoreceptor of type (1) is too small, the sensitivity will be poor, and if it is too large, the charging property will be poor, the strength of the electrophotographic photosensitive layer will be weakened, and the electrophotographic photoreceptor will have poor sensitivity. The proportion of the phthalocyanine pigment in the layer is 0.01 to 2 times the weight of the binder.
Preferably it is 0.05 to 1 times.

The ratio of the charge transport compound represented by general formula (VII) to the binder is 0.1 to 2 times, preferably 0.3 times.
A range of 1.3 to 1.3 times the weight is preferable.

The content of the compounds represented by formulas (I) to (VI) is suitably in the range of 0.01 to 1 times, preferably 0.02 to 0.4 times by weight, relative to the phthalocyanine pigment.

In addition, when forming a phthalocyanine compound-containing layer which becomes a charge generation layer in types (2) and (3) electrophotographic photoreceptors, the amount of phthalocyanine pigment used is preferably 0.1 to 50 times the binder resin. If it is less than that, sufficient photosensitivity cannot be obtained. The proportion of the charge transport compound represented by the general formula (VII) in the charge transport medium is 0.01 to 10 times the weight of the binder, preferably 0.01 to 10 times the weight of the binder.
2-2x magnification is preferred.

In this case as well, the content of the compounds represented by general formulas (r) to (Vl) is 0.0 with respect to the phthalocyanine pigment.
A suitable range is 1 to 1 times by weight, preferably 0.02 to 0.4 times by weight.

In addition, in photoconductors of type (2) and (3),
0-196767, JP-A No. 60-254045, and JP-A No. 60-262159, charge transport compounds such as hydrazone compounds and oxime compounds are added to the charge generation layer. You can also do it.

The conductive support used in the electrophotographic photoreceptor of the present invention is a metal plate made of aluminum, copper, zinc, stainless steel, etc., a metal drum, or a sheet made of plastic, paper, etc. Papers coated with conductive materials such as Column, 5nOz, carbon, etc., or coated with conductive polymers, or conductively treated with inorganic salts such as sodium chloride, calcium chloride, or organic quaternary ammonium salts, Paper tubes, phenol resin drums molded with carbon, Bakelite drums, etc. are used.

The binder used in the charge generation layer of types (2) and (3) of the present invention can be selected from a wide range of insulating resins, such as polyester resins, cellulose resins, acrylic resins, polyamide resins, polyvinyl butyral resins, Phenoxy resin, polyvinyl formal resin,
Examples include, but are not limited to, polycarbonate resin, styrene resin, polybutadiene resin, polyurethane resin, epoxy resin, silicone resin, vinyl chloride resin, vinyl chloride-vinyl acetate resin, and the like.

As the binder used in the charge transport layer, it is preferable to use a film-forming polymer that is hydrophobic, has a high dielectric constant, and is electrically insulating.

Examples of such high molecular weight polymers include, but are not limited to, the following.

Polycarbonate, polyester, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-
Vinyl acetate-maleic anhydride copolymer, silicone resin,
Examples include silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, and poly-N-vinylcarbazole.

The binder for the photoconductive layer of type (1) can be appropriately selected from the binders for the charge generation layer and charge transport layer described above.

These binders can be used alone or as a mixture of two or more.

When producing the electrophotographic photoreceptor of the present invention, additives such as a plasticizer or a sensitizer may be used together with the binder.

Plasticizers include biphenyl, chlorinated biphenyl, 0-terphenyl, p-terphenyl, dibutyl phthalate, dimethyl glycol phthalate, dioctyl phthalate,
Triphenyl phosphoric acid, methylnaphthalene, benzophenone, chlorinated paraffin, polypropylene, polystyrene,
dilauryl thiodipropionate, 3,5-dinitrosalicylic acid, dimethyl phthalate, dibutyl phthalate,
Examples include diisobutyl adipate, dimethyl sebacate, dibutyl sebacate, butyl laurate, methyl phthalyl ethyl glycolate, various fluorohydrocarbons, and the like.

In addition, silicone oil or the like may be added to improve the surface properties of the electrophotographic photoreceptor.

As sensitizers, chloranil, tetracyanoethylene,
Examples include methyl violet, rhodamine B1 cyanine dye, merocyanine dye, biryllium dye, thiapyrylium dye, compounds described in JP-A Nos. 58-65439, 58-102239, 58129439, 62-71965, etc. can.

As a coating solvent, alcohols (e.g. methanol,
ethanol, isopropanol, etc.), ketones (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), amide B (e.g., N,
N-dimethylformamide, N,N-dimethylacetamide, etc.), esters (e.g., methyl acetate, ethyl acetate, butyl acetate, etc.), ethers (e.g., tetrahydrofuran, dioxane, monoglyme, diglyme, etc.)
, halogenated hydrocarbons (for example, methylene chloride, chloroform, methylchloroform, carbon tetrachloride, monochlorobenzene, dichlorobenzene, etc.) can be used alone or in combination.

Application can be performed using general-purpose coating methods such as spraying, roller coating, spinner coating, blade coating, dip coating, and the like.

Further, in the present invention, an adhesive layer or a barrier layer can be provided between the conductive support and the photoconductive layer, if necessary. Materials used for these layers include, in addition to the high molecular weight polymer used for the binder, gelatin, casein, polyvinyl alcohol, ethyl cellulose, carboxy-methyl cellulose, and JP-A-59-84247.
vinylidene chloride-based polymer latex described in JP-A-59-114544, aluminum oxide, etc., and the thickness of these materials is preferably 0°1 to 5 μm. .

In addition, in the present invention, light m? An overcoat layer can be provided on itrM if necessary. This overcoat layer may be a mechanically capped layer or a resin layer containing a capping agent. in this case,
Mantle agents include silicon dioxide, glass particles, alumina,
Particles of polymers such as starch, titanium oxide, zinc oxide, polymethyl methacrylate, polystyrene, phenolic resins, and U.S. Pat.
The matting agents described in No. 992.101 are included. Two or more of these can be used in combination.

The resin used for the overcoat layer can be selected from various known resins in addition to those used for the photoconductive layer.

The present invention has been described in detail above, and the electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor with excellent sensitivity, little change in charging potential during repeated use, low residual potential, rigidity, and high durability. be.

The electrophotographic photoreceptor of the present invention can be widely applied to photoreceptors for printers using lasers and cathode ray tubes as light sources, as well as electrophotographic copying machines.

Since it has high sensitivity particularly in the long wavelength range, it is suitable for laser beam printers using semiconductor lasers, He--Ne lasers, etc. as light sources.

EXAMPLES Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the Examples. In the examples, "parts" indicate "parts by weight J."

Example I C-type copper phthalocyanine (Lisphoton EPPC: manufactured by Toyo Ink Gl) 0.5 parts Exemplified compound o) 0.05 parts Polyester resin (Vylon 200: manufactured by Toyobo ■) 3.0 parts Exemplified compound (68) 3 .0 part 1 part of tetrahydrofuran was placed in a 500-glass container together with glass beads and dispersed for 60 minutes using a paint shaker (Toyo Seisakusho 9W), and then the glass beads were filtered to obtain a photoconductive layer dispersion. .

Next, this photoconductive layer dispersion was applied onto a conductive support (a 75 μm polyethylene terephthalate film with an aluminum film coated on the surface; surface resistance: 10'Ω) using a wire round iron, and dried. and 20μm
An electrophotographic photoreceptor having a photoconductive layer was obtained.

Next, the electrical properties of the produced electrophotographic photoreceptor were determined using EPA-8
100 (manufactured by Kawaguchi Electric Co., Ltd.) under the conditions of static corona charging at +8.0 kV and exposure to monochromatic light of 780 parts m at a light intensity of 1 mw/lri. Surface potential (■.) immediately after charging, 10 from immediately after charging
The ratio of the surface potential after seconds to Vo is the charge retention rate (DD,
. ), and the sensitivity is the exposure amount (BS.) at which the surface potential before exposure is photo-attenuated to 1/2, the exposure amount at which the surface potential becomes 1/10 (CF, 9°), and the exposure amount as the residual potential (■8). 100μ
When the surface potential at the time of J/cj was investigated, it was found to be V, +670V E5. 1.9μJ/co! E.
It was 4.6 μJ/cJa DD+o 78% Vl +15V.

Comparative Example 1 From the photoconductive layer coating solution of Example 1, exemplified compound f1. )
An electrophotographic photoreceptor was produced in exactly the same manner as in Example 1 except for the following. The electrical characteristics of this electrophotographic photoreceptor were measured under the same conditions as in Example 1, and found that Vo +720V ESll 2. 5uJ/c11! E'+o
7.8μJ/cnlDD,. It was 80% V, +39V.

Example 2 3 parts of ε-type copper phthalocyanine (Lisphoton EPPC), 3 parts of exemplified compound (110.3 parts) and polyester resin (
After dispersing 3 parts of Byron 200) in 100 parts of tetrahydrofuran in a ball mill for 20 hours,
Using a wire round iron, it was coated onto a conductive support (the above-mentioned Al vapor deposited film) and dried to obtain a charge generation layer with a thickness of 0.5 μm.

Next, 10 parts of Exemplified Compound (76) and 10 parts of polycarbonate of bisphenol A were dissolved in 50 parts of dichloromethane as a charge transport substance on the charge generation layer (7 parts of the mixture was coated using a wire round lot). , dry,
An electrophotographic photoreceptor was prepared by forming a charge transport layer with a thickness of 20 μm. The electrical characteristics of this electrophotographic photoreceptor are 18K.
As a result of measurement under the same conditions as in Example 1 except that corona charging was carried out at V, the result was Vo 750V E. 1.4μJ/cn! E. 2.9 μJ/cd DDl,, 75% V! l 21 V. Thereafter, the two steps of charging and exposure were repeated 10,000 times, and the electrical properties were examined, but there was almost no change from the properties before repeating.

Comparative Example 2 An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 2, except that Exemplary Compound +11 of Example 2 was removed.

The electrical characteristics of this electrophotographic photoreceptor were measured under the same conditions as in Example 2, and found to be V, -743V ESo 2.1 μJ/(JIE, 6.0 μJ/ca DD, 83% V, -29V .

Comparative Example 3.4 An electrophotographic photoreceptor was prepared in the same manner as in Example 2, except that the following comparative compound was used instead of Exemplary Compound (76) as a charge transport material, and the electrical properties were measured. did. The results are shown in Table 1.

Comparative compound f1+ Comparative compound (2) Table 1 Example 3 ε-type copper phthalocyanine of Example 2 (Liophuoton EP
An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 2, except that X-type metal-free phthalocyanine (PC) was replaced with X-type metal-free phthalocyanine (Fastoghan Blue 8120, manufactured by Dainippon Ink ■). The electrical properties of this electrophotographic photoreceptor were measured under the same conditions as in Example 2, and the result was ■. -756■ E,. 0.6 μJ/cJ E90 1. 6 μJ/c+jDD,.
It was 76% v, -11V. Thereafter, the two steps of charging and exposure were repeated 10,000 times and the electrical properties were examined, but there was almost no change from the properties before repeating.

Comparative Example 5 An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 3 except for the exemplified compound [11] of Example 3.

The electrical characteristics of this electrophotographic photoreceptor were measured under the same conditions as in Example 2, and found to be Vo 740 VE. 0.9 μJ/ct E, +, 2. −9 μJ/ctlDD,.

79% V, -18V Met.

Example 4 ε-type steel phthalocyanine (Liophoton E) of Example 2
An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 2 (1) except that PPC) was replaced with α-type titanyl copper phthalocyanine (manufactured by Toyo Ink). The electrical characteristics of this electrophotographic photoreceptor were measured under the same conditions as in Example 2, and the results were vo -710V E. 0.4 μJ/ca E,. 1.1 μJ/cjDD+o
It was 77% V* -9V. Thereafter, the two steps of charging and exposure were repeated 10,000 times and the electrical properties were examined, but there was almost no change from the properties before repeating.

Comparative Example 6 The electrical properties of the electrophotographic photoreceptor were measured in the same manner as in Example 3 using the exemplified compound of Example 4 (except for 11) under the same conditions as in Example 2. Results (■) -726v Eso 0. 1ttJ/c:dEqe
2. 1 p J /CJJDD,. It was 77% v, -19V.

Examples 5 to 25 As a sensitizer, the exemplified compound shown in Table 2 was used instead of the exemplified compound (1) of Example 3, and as a charge transport substance, Example 3 was used.
An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 3, except that the exemplified compounds shown in Table 2 were used in place of exemplified compound (76). The electrical properties of this electrophotographic photoreceptor are shown in Table 2. The electrical properties were measured under the same conditions as in Example 2.

Example 1 and Comparative Example 1, Examples 2.5 to 25 and Comparative Example 2 to
4. Comparing Example 3 and Comparative Example 5, and Example 4 and Comparative Example 6, it was found that -S contains a compound represented by formula (VII), and has general formulas (1) to (VT) The electrophotographic photoreceptor containing the compound shown above has a range of 1.5 to 2 times higher than that of the comparative photoreceptor. Furthermore, it can be seen that good electrophotographic properties are maintained without any large differences in chargeability, dark decay, or residual potential. Furthermore, in Example 2.3.4, it was confirmed that the electrical characteristics after repeated use Lo, 000 times were almost unchanged from the initial characteristics.

As described above, the electrophotographic photoreceptor shown in the examples satisfies the object of the present invention, ``a highly durable electrophotographic photoreceptor that is highly sensitive, has high potential stability during repeated use, and has a low residual potential.'' I can see that it is something.

Claims (2)

[Claims] (1) In an electrophotographic photoreceptor in which a photoconductive layer is provided on a conductive support, the photoconductive layer contains a) a phthalocyanine pigment, b)
Electrophotography for copying machines or optical printers, characterized in that it contains at least one of the compounds represented by general formulas (I) to (VI), and c) at least one of the compounds represented by general formula (VII). Photoreceptor. General formula (I) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ General formula (II) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ General formula (III) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ General formula (IV) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ General formula (V) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ General formula (VI) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ General formula (VII) ▲ Numerical formulas, chemical formulas, There are tables, etc.▼ In the general formulas (I) to (VII), Z represents a sulfur atom or an oxygen atom. R^1, R^2, R^3, R^4, R^5, and R^6 each represent a monovalent group derived from a hydrogen atom, an alkyl group, an aryl group, or a heterocycle, and may be the same or different from each other. It's okay. R^1 and R^2, or R^3 and R^4 may each be connected. In general formula (I), R^
1, R^2, R^3, and R^4 may be linked together to form a bridged ring as a whole. R^7 represents a divalent arylene group, aralkylene group, polymethylene group or alkylene group. R^8 represents an alkyl group, an alkoxy group, a monocyclic or bicyclic fused aryl group, a monocyclic or bicyclic fused aryloxy group, or a monovalent group derived from a heterocycle. In general formula (V), two R^■ may be the same or different. R^9 and R^1^0 represent an alkyl group, an aryl group, or an aralkyl group, and R^9 and R^1^0 may be the same or different groups. R^1^1 represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. Furthermore, Ar_1 and R^1^1 may form a ring. R^1^2 and R^1^3 represent an alkyl group, an aralkyl group, and an aryl group, and R^1^2 and R^1^3 may be the same or different from each other, and R^1^2 , R^1^
3 may form a heterocycle. R^1^4 represents a hydrogen atom, an alkyl group, or an aryl group. Ar_1, Ar_2 are monovalent aromatic hydrocarbon groups or 1
represents a valent heterocyclic group. n represents an integer of 0 or 1. (2) The electrophotographic photoreceptor for a copying machine or optical printer according to claim 1, wherein the light source of the copying machine or optical printer is a laser beam.