JPH0580550A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body having high sensitivity and high durability. CONSTITUTION:This electrophotographic sensitive body contains a triarylamine compd. in the photosensitive layer formed on the electric conductive substrate. The triarylamine compd. has one or more triarylamine skeletons represented by the formula (where each of Ar1-Ar3 is optionally substd. aryl and Ar1-Ar3 may be different from each other) and an alkylenecarboxylic ester group represented by a formula -(CH2)m-COOR [where R is optionally substd. alkyl, aralkyl or aryl and (m) is an integer of 1-6] has been substd. for at least one of the aryl groups.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic photoreceptor. More specifically, it relates to a highly sensitive and highly durable electrophotographic photoreceptor containing a specific triarylamine compound.

[0002]

2. Description of the Related Art In recent years, electrophotographic copying machines and printers have been remarkably developed, and various types of models having various forms, types, and functions have been developed according to their uses, and correspondingly, photoconductors used for them have also been developed. A wide variety of things are being developed. Conventionally, inorganic compounds have been mainly used as electrophotographic photoreceptors from the viewpoint of sensitivity and durability. Examples thereof include zinc oxide, cadmium sulfide and selenium. However, these often use harmful substances, and their disposal poses a problem and causes pollution. When using selenium, which has good sensitivity,
It is necessary to form a thin film on the conductive substrate by a vapor deposition method or the like, which is inferior in productivity and causes a cost increase. recent years,
Amorphous silicon has attracted attention as a non-polluting inorganic photoconductor, and research and development thereof are underway. However, although these are also excellent in sensitivity, the productivity is extremely poor because the plasma CVD method is mainly used when forming a thin film, and the photoreceptor cost and the running cost are large.

On the other hand, the organic photoconductor can be incinerated,
It has the advantage of being pollution-free, and many of them can be formed into thin films by coating and are easy to mass-produce. Therefore, it has an advantage that the cost can be significantly reduced and that it can be processed into various shapes depending on the application. However, with respect to the organic photoconductor, problems remain in its sensitivity and durability, and it is strongly desired to develop an organic photoconductor with high sensitivity and high durability. Various methods have been proposed as means for improving the sensitivity of the organic photoconductor, but at present, a function-separated photoconductor mainly having a two-layer structure in which the functions are separated into a charge generation layer and a charge transport layer has become mainstream. There is. For example, the charge generated in the charge generation layer by exposure is injected into the charge transport layer, transported through the charge transport layer to the surface, and the surface charge is neutralized to form an electrostatic latent image on the surface of the photoreceptor. To be done. Compared to the single-layer type, the function-separated type has a smaller possibility of trapping the generated charges, and each layer can efficiently transport the charges to the surface of the photoconductor without hindering the function of each layer (US Patent No. 2803541). As the organic charge generating material used in the charge generating layer, a compound that absorbs the energy of irradiated light and efficiently generates charges is used, for example, an azo pigment (JP-A-54-14967). ), A metal-free phthalocyanine pigment (JP-A-60-19146),
Metal phthalocyanine pigment (JP-A-57-146255),
Squarium salt (Japanese Patent Laid-Open No. 63-113462) and the like can be mentioned. As the charge transport material used in the charge transport layer, it is necessary to select a compound having a high charge injection efficiency from the charge generation layer and a high charge mobility in the charge transport layer. For that purpose, a compound having a small ionization potential or a compound which easily generates a cation radical is selected.
58-123542), hydrazone derivatives (JP-A-57-10)
1844), oxadiazole derivatives (Japanese Patent Publication No. 34-54).
66), pyrazoline derivatives (Japanese Patent Publication No. 52-4188), stilbene derivatives (Japanese Patent Publication No. 58-198043),
Triphenylmethane derivative (Japanese Patent Publication No. 45-555),
1,3-Butadiene derivatives (JP-A-62-287257) and the like have been proposed.

[0004]

However, as described above, these organic photoreceptors are still not satisfactory in terms of sensitivity and durability as compared with inorganic photoreceptors. The sensitivity is governed by the charge generation efficiency in the charge generation layer, the charge injection efficiency from the charge generation layer to the charge transport layer, and the charge mobility in the charge transport layer. Therefore, a charge generating material having a high charge generating efficiency and a charge transporting material having a high charge mobility have been actively developed. On the other hand, the fact is that the injection efficiency has hardly been studied and improved.
This injection efficiency is as high as 50% in the high electric field region, and in the low electric field region
It is less than 10%, and by increasing this injection efficiency,
It is considered that the sensitivity can be further increased. Generally, in order to efficiently inject holes from the charge generation layer to the charge transport layer, it is necessary to make the ionization potential of the charge transport material smaller than that of the charge generation material to eliminate the energy barrier. However, even if this condition is satisfied, the injection efficiency is often low. As one of the causes, it is considered that partial microcrystals of the charge transport material or the binder used in the charge transport layer serve as a barrier. Another is a barrier due to an interface defect between the charge generation layer and the charge transport layer. These are the adhesion between the charge generation layer and the charge transport layer, poor adhesion, morphological defects that occur during drying after coating, physical irritation during use (toner,
It may be caused by crystallization due to stimulation with an electric field) or contact with paper or a cleaning blade).

As a method of solving these problems, use of a charge transport material having a lower crystallinity and excellent compatibility, use of a binder, and selection of a charge transport material having excellent adhesiveness and adhesion and a binder are considered. Be done. However, up until now, the materials developed for such purpose, except for the special polycarbonate binder,
rare. Further, the same cause can be considered for the problem of durability. That is, if some kind of barrier is present at the interface between the charge generation layer and the charge transport layer, space charges are accumulated there, causing an increase in residual potential and destabilization of the photosensitive member surface potential. Further, the accumulation of the space charge causes deterioration of the charge transport material, which makes it impossible to withstand continuous use. As a method for eliminating this space charge, the same means as described above is considered effective. The object of the present invention lies in this point, and it is to provide an electrophotographic photosensitive member having high sensitivity and high durability as a solution to such problems.

[0006]

As a result of intensive research to solve the above problems, the inventors have found that a triarylamine compound having a specific alkylenecarboxylic acid ester group has low crystallinity as a charge transport material, The inventors have found that the compatibility with a binder is excellent, and that the charge transport layer using the same has good adhesiveness with the charge generation layer, and completed the present invention. That is, the present invention, in the photosensitive layer provided on the conductive support, the general formula (1)

[0007]

[Chemical 6]

(In the formula, Ar ₁ , Ar ₂ and Ar ₃ are the same or different and each represents an optionally substituted aryl group.)
Having one or more triarylamine skeletons represented by and at least one of the aryl groups has the formula-(C
H ₂ ) _m- COOR (R represents an optionally substituted alkyl group, aralkyl group or aryl group, m represents an integer of 1 or more and 6 or less) and is substituted with an alkylenecarboxylic acid ester group. The present invention provides an electrophotographic photosensitive member characterized by containing a triarylamine compound.
Examples of the triarylamine compound used in the present invention include compounds represented by the following general formulas (2) to (5).

[0009]

[Chemical 7]

(In the formula, Ar ₄ , Ar ₅ and Ar ₆ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula-(CH ₂ ) _m- COOR
(R and m have the same meanings as described above) and are substituted with an alkylenecarboxylic acid ester group. )

[0011]

[Chemical 8]

(In the formula, Ar ₇ , Ar ₈ , Ar ₁₀ and Ar ₁₁ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula — (CH ₂ ) _m
It is substituted with an alkylenecarboxylic acid ester group represented by —COOR (R and m have the same meanings as described above). Ar ₉ represents an optionally substituted arylene group. )

[0013]

[Chemical 9]

(In the formula, Ar ₁₂ , Ar ₁₃ , Ar ₁₆ and Ar ₁₇ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula-(CH ₂ ) _m
It is substituted with an alkylenecarboxylic acid ester group represented by —COOR (R and m have the same meanings as described above). Ar ₁₄ and Ar ₁₅ are the same or different and each represents an optionally substituted arylene group. )

[0015]

[Chemical 10]

(In the formula, Ar ₁₈ , Ar ₁₉ , Ar ₂₂ and Ar ₂₃ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula-(CH ₂ ) _m
It is substituted with an alkylenecarboxylic acid ester group represented by —COOR (R and m have the same meanings as described above). Ar ₂₀ and Ar ₂₁ are the same or different and each represents an optionally substituted arylene group. X is an oxygen atom, a sulfur atom, -CH ₂ - represents or -CH = CH-. ) The general formula (1)
In (5), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ ,
Ar ₈ ,, Ar ₁₀ ,, Ar ₁₁ , Ar ₁₂ , Ar ₁₃ , Ar ₁₆ , Ar ₁₇ , Ar ₁₈ , Ar
₁₉ , Ar ₂₂ and Ar ₂₃ are the same or different and each represents an optionally substituted aryl group, and examples of the aryl group include groups such as phenyl, naphthyl and anthranyl, and a phenyl group and a naphthyl group are preferable. .. The aryl group may be substituted, but the substituent is usually an alkyl group, an alkoxy group or the like, a methyl group, an ethyl group,
A methoxy group and an ethoxy group are preferable. At least one aryl group in one molecule may also formula _{- (CH 2) m -COOR (} R and
m has the same meaning as described above. ) Is substituted with an alkylenecarboxylic acid ester group, but preferably one aryl group in one molecule is substituted with the above alkylenecarboxylic acid ester group. R represents an optionally substituted alkyl group, aralkyl group or aryl group, and the alkyl group is preferably a linear or branched alkyl group having 1 to 8 carbon atoms, specifically, methyl, ethyl, n -Propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, n-hexyl, n-
Examples thereof include groups such as heptyl and n-octyl, with methyl, ethyl, n-propyl, isopropyl and n-butyl groups being preferred. This alkyl group may be substituted, but the substituent usually includes an alkoxy group, and preferably a methoxy group or an ethoxy group. When R is an aralkyl group, examples thereof include phenyl, naphthyl, and anthranyl groups in which the aryl group moiety is unsubstituted or substituted with an alkyl group, an alkoxy group, and the like. And preferably methylene. Specific examples thereof include groups such as benzyl, p-methylbenzyl and m-methylbenzyl. When R is an aryl group, an unsubstituted or alkyl group,
Examples thereof include groups such as phenyl, naphthyl and anthranyl substituted with an alkoxy group and the like, with a phenyl group being preferred. m is an integer of 1 or more and 6 or less, and preferably 1. _{Ar 9, Ar 14, Ar 15} , Ar 20, Ar 21 is different from the same or different, show an optionally substituted arylene group, the arylene group, a phenylene group, a naphthylene group, Ansuraniren group and the like are exemplified, preferably Is a phenylene group,
It is a naphthylene group. Examples of the substituent usually include an alkyl group and an alkoxy group, and a methyl group, an ethyl group,
A methoxy group and an ethoxy group are preferable.

The triarylamine compound used in the present invention can be synthesized by a known method. For example,
First, a halogenomethyltriarylamine compound is converted into a Grignard and reacted with carbon dioxide to give a methylenecarboxylic acid (acetic acid) derivative. Then, it may be esterified by reacting with the corresponding alcohol. The triarylamine-based compound according to the present invention obtained as described above has low crystallinity and has very excellent compatibility with a solvent and a binder. Furthermore, - (CH ₂₎ its charge mobility than an triarylamine compound not substituted with _m -COOR are those little difference greater without. Therefore, an electrophotographic photoreceptor having high sensitivity and high durability is provided. Specific examples of the triarylamine compound used in the present invention are shown below (compound (6)
~ (233)), the present invention is not limited to these.

[0018]

[Chemical 11]

[0019]

[Chemical formula 12]

[0020]

[Chemical 13]

[0021]

[Chemical 14]

[0022]

[Chemical 15]

[0023]

[Chemical 16]

[0024]

[Chemical 17]

[0025]

[Chemical 18]

[0026]

[Chemical 19]

[0027]

[Chemical 20]

[0028]

[Chemical 21]

[0029]

[Chemical formula 22]

[0030]

[Chemical formula 23]

[0031]

[Chemical formula 24]

[0032]

[Chemical 25]

[0033]

[Chemical formula 26]

[0034]

[Chemical 27]

[0035]

[Chemical 28]

[0036]

[Chemical 29]

[0037]

[Chemical 30]

[0038]

[Chemical 31]

[0039]

[Chemical 32]

[0040]

[Chemical 33]

[0041]

[Chemical 34]

[0042]

[Chemical 35]

[0043]

[Chemical 36]

[0044]

[Chemical 37]

[0045]

[Chemical 38]

[0046]

[Chemical Formula 39]

[0047]

[Chemical 40]

[0048]

[Chemical 41]

[0049]

[Chemical 42]

[0050]

[Chemical 43]

[0051]

[Chemical 44]

[0052]

[Chemical 45]

[0053]

[Chemical 46]

[0054]

[Chemical 47]

[0055]

[Chemical 48]

[0056]

[Chemical 49]

[0057]

[Chemical 50]

[0058]

[Chemical 51]

[0059]

[Chemical 52]

[0060]

[Chemical 53]

[0061]

[Chemical 54]

[0062]

[Chemical 55]

[0063]

[Chemical 56]

These compounds are soluble in many solvents, for example, aromatic solvents such as benzene, toluene, xylene, tetralin and chlorobenzene; halogen-based solvents such as dichloromethane, chloroform, trichloroethylene, tetrachloroethylene and carbon tetrachloride. Solvents; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, methyl formate, ethyl formate; ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as diethyl ether, dipropyl ether, dioxane, tetrahydrofuran; methanol, ethanol , Isopropyl alcohol and other alcohol solvents; soluble in dimethylformamide, dimethylacetamide, dimethylsulfoxide and the like.

In producing the electrophotographic photosensitive member,
For example, the charge generation layer and the charge transport layer are formed in a thin film on the conductive support. As the base material of the conductive support,
A metal such as aluminum or nickel, a metal vapor deposition polymer film, a metal laminated polymer film, or the like can be used, and the conductive support is formed in a drum shape, a sheet shape, or a belt shape.

The charge generation layer is composed of a charge generation material and, if necessary, a binder and an additive.
It can be prepared by a method such as a coating method or a coating method. The charge generating material is not particularly limited, and any organic material or inorganic material can be suitably used as long as it absorbs light having a specific wavelength to be irradiated and can generate charge more efficiently. However, in the case of an inorganic material, as described above, there are problems of pollution and economical efficiency. Therefore, it is preferable to use an organic material from this viewpoint. As an organic charge generation material,
Examples thereof include perylene pigments, polycyclic quinone pigments, metal-free phthalocyanine pigments, metal phthalocyanine pigments, bisazo pigments, trisazo pigments, thiapyrylium salts, squarium salts, and azurenium pigments, and these are mainly dispersed in a binder and coated. The charge generation layer can be formed by processing. As the inorganic charge generating material, selenium,
Examples thereof include selenium alloy, cadmium sulfide, zinc oxide, amorphous silicon, amorphous silicon carbide and the like. The thickness of the charge generation layer formed is 0.1 to 2.0 μm.
Is preferable, and more preferably 0.1 to 1.0 μm.

Next, a charge transport layer containing the triarylamine compound according to the present invention is formed in a thin film on the charge generation layer. As the thin film forming method, a coating method is mainly used, and the triarylamine compound according to the present invention is dissolved in a solvent together with a binder as necessary,
It may be applied on the charge generation layer and then dried.
The solvent used is not particularly limited as long as it is a solvent in which the above compound and the binder used as the case requires and the charge generation layer does not dissolve. The binder used if necessary is not particularly limited as long as it is an insulating resin, for example, polycarbonate, polyarylate,
Condensation polymers such as polyester and polyamide; polyethylene, polystyrene, styrene-acrylic copolymers; polyacrylate, polymethacrylate, polyvinyl butyral, polyacrylonitrile, polyacrylamide,
Addition polymers such as acrylonitrile-butadiene copolymer, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer;
Polysulfone, polyether sulfone, silicone resin, etc. are appropriately used, and one kind or a mixture of two or more kinds can be used. The amount of the above-mentioned binder used is 0.1 to 3% by weight, preferably 0.1 to 2% by weight, based on the triarylamine compound according to the present invention. If the amount of the binder is larger than this, the concentration of the charge transport material in the charge transport layer will be low and the sensitivity will be poor.

Further, in the present invention, the above-mentioned known charge transport materials may be used in combination, if necessary. The means for coating the charge transport layer is not particularly limited, and for example, a dip coater, a bar coater, a calendar coater, a gravure coater, a spin coater or the like can be used as appropriate, and it is also possible to perform electrodeposition coating. is there. The thickness of the charge transport layer thus formed is
10 to 50 μm is preferable, more preferably 10 to 30 μm
Is. If the film thickness is larger than 50 μm, it takes a long time to transport the charges, and the probability of trapping the charges is high, which causes a decrease in sensitivity. On the other hand, 10 μm
If it is smaller, the mechanical strength is lowered and the life of the photoreceptor is shortened, which is not preferable.

As described above, an electrophotographic photoreceptor containing the triarylamine compound according to the present invention in the charge transport layer can be prepared. In this electrophotographic photosensitive member, the adhesion between the charge generation layer and the charge transport layer is excellent,
In the cellophane tape peel test, there was no peeling at all. Further, in the present invention, an adhesive layer, an undercoat layer, and a conductive layer between the conductive support and the charge generation layer, if necessary
A barrier layer or the like can be provided.

When the electrophotographic photosensitive member thus obtained is used, the surface of the photosensitive member is first charged negatively by a corona charger or the like. After being charged, by exposure, charge is generated in the charge generation layer, and positive charges are injected into the charge transport layer, which are transported to the surface through the charge transport layer,
The negative charge on the surface is neutralized. On the other hand, negative charges remain in the unexposed areas. In the case of regular development, positively charged toner is used, and the toner is attached to the portion where the negative charge remains to be developed. In the case of reversal development,
Negatively charged toner is used, and the toner is attached to the portion where the charge is neutralized and developed. The electrophotographic photosensitive member of the present invention can be used in any developing method and can provide high image quality. Further, the charge transport material is never crystallized during repeated use, and neither the charge generation layer nor the charge transport layer is peeled off. Furthermore, no increase in residual potential is observed, and high sensitivity and high durability can be exhibited. Further, in the present invention, an electrophotographic photoreceptor can be prepared by first providing a charge transport layer on a conductive support and then providing a charge generation layer thereon. In this case, first, the surface of the photoconductor is positively charged, and after exposure, the generated negative charge neutralizes the surface charge of the photoconductor, and the positive charge is transported to the conductive support through the charge transport layer. It will be.

[0071]

EXAMPLES The present invention will now be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Synthesis Example 1 n-Butyl 4-diphenylaminophenylacetate (Example
A compound stirrer for compound (10)) , a cooling tube, a nitrogen introducing tube, and a dropping funnel were provided.
Magnesium metal 2.9 g (0.12 m
ol) was added and the atmosphere was replaced with nitrogen. Then, 300 ml of dry diethyl ether was added and stirring was started. 100 ml of a diethyl ether solution of 29.3 g (0.1 mol) of 4-chloromethyltriphenylamine was slowly added dropwise thereto. When about 10 ml was dropped, a gentle reflux started. While refluxing, the diethyl ether solution was further added dropwise, and after completion of the addition, the mixture was refluxed for 1 hour. The Grignard reagent solution obtained as described above was returned to room temperature, and then 13 g of dry ice was slowly added thereto under ice cooling. After all the dry ice was added, the reaction mixture was stirred for 2 hours at room temperature to age the reaction. Then, 100 ml of water was added dropwise under ice cooling for hydrolysis. The resulting mass was dissolved by adding 0.1N hydrochloric acid solution. Next, the ether layer was extracted, washed twice with a saturated aqueous sodium hydrogen carbonate solution and twice with water, and then dried over anhydrous sodium sulfate. After drying, diethyl ether was distilled off to obtain a white solid. The white solid was recrystallized from ethanol to give 4-diphenylaminophenylacetic acid (24.9 g, yield).
81%). Next, 24.9 g (0.081 mol) of this 4-diphenylaminophenylacetic acid was dissolved in 500 ml of n-butanol by heating, 2 ml of sulfuric acid was added, and the mixture was refluxed for 5 hours. After that, the temperature was returned to room temperature, and the reaction mixture was poured into 2 liters of water.
The white solid obtained was filtered and dried. This white solid was purified by a silica gel column, and 21.5 g of the target product, n-butyl 4-diphenylaminophenyl acetate.
(74%) obtained.

Rf = 0.6 (ethyl acetate / n-hexane = 1/3) Melting point: 124.2 to 125.1 ° C. Synthesis example 2 Synthesis of triarylamine compound (Exemplified compound (64)) Stirrer, cooling tube, nitrogen introducing tube Equipped with a dropping funnel
Magnesium metal 2.9 g (0.12
(mol) was added and nitrogen substitution was performed. Then, 300 ml of dry diethyl ether was added and stirring was started. Then, 100 ml of a diethyl ether solution containing 50.9 g (0.1 mol) of bis [4- (chloromethylphenyl) phenyl] -p-phenylenediamine was slowly added dropwise. When about 10 ml was dropped, a gentle reflux started. While refluxing, the diethyl ether solution was further added dropwise, and after completion of the addition, the mixture was refluxed for 1 hour. The Grignard reagent solution obtained as described above is returned to room temperature, and then cooled there under ice,
13 g of dry ice was slowly added. After all the dry ice was added, the reaction mixture was stirred for 2 hours at room temperature to age the reaction. Then, 100 ml of water was added dropwise under ice cooling for hydrolysis. The resulting mass was dissolved by adding 0.1N hydrochloric acid solution.
Next, the ether layer was extracted, washed twice with a saturated aqueous sodium hydrogen carbonate solution and twice with water, and then dried over anhydrous sodium sulfate. After drying, diethyl ether was distilled off to obtain a white solid. The white solid was recrystallized from ethanol to obtain 42.2 g (yield 83%) of a biscarboxylic acid derivative. Next, 42.2 g (0.083 mol) of this biscarboxylic acid derivative was dissolved by heating in 500 ml of n-butanol, 2 ml of sulfuric acid was added, and the mixture was refluxed for 5 hours. After that, the temperature was returned to room temperature, and the reaction mixture was poured into 2 liters of water. The white solid obtained was filtered and dried. This white solid was purified by a silica gel column to obtain the target product, a triarylamine compound (Exemplified compound (64)).
Obtained 48.3 g (91%).

Rf = 0.7 (ethyl acetate / n-hexane = 1/3) Melting point: 128.8-129.6 ° C. Synthesis example 3 Synthesis of triarylamine compound (Exemplified compound (102)) Stirrer, cooling tube, nitrogen introducing tube Equipped with a dropping funnel
Magnesium metal 2.9 g (0.12
(mol) was added and nitrogen substitution was performed. Then, 300 ml of dry diethyl ether was added and stirring was started. There, screw-
100 ml of a diethyl ether solution of 58.5 g (0.1 mol) of 4,4 '-[(p-chloromethylphenyl) phenylamino] biphenyl was slowly added dropwise. When about 10 ml was dropped, a gentle reflux started. While refluxing, the diethyl ether solution was further added dropwise, and after completion of the addition, the mixture was refluxed for 1 hour. The Grignard reagent solution obtained as described above is returned to room temperature, and then cooled there under ice,
13 g of dry ice was slowly added. After all the dry ice was added, the reaction mixture was stirred for 2 hours at room temperature to age the reaction. Then, 100 ml of water was added dropwise under ice cooling for hydrolysis. The resulting mass was dissolved by adding 0.1N hydrochloric acid solution. Next, the ether layer was extracted, washed twice with a saturated aqueous sodium hydrogen carbonate solution and twice with water, and then dried over anhydrous sodium sulfate. After drying, diethyl ether was distilled off to obtain a white solid. The white solid was recrystallized from ethanol to obtain 48.6 g (yield 76%) of a biscarboxylic acid derivative. Next, 48.6 g (0.076 mol) of this biscarboxylic acid derivative
-Dissolve in 500 ml butanol by heating, add 2 ml sulfuric acid and
Refluxed for hours. After that, the temperature was returned to room temperature, and the reaction mixture was poured into 2 liters of water. The white solid obtained was filtered and dried. The white solid was purified by a silica gel column to obtain 44.1 g (81%) of the target triarylamine compound (Exemplified compound (102)).

Rf = 0.5 (ethyl acetate / n-hexane = 1/2) Melting point: 145.2 to 146.6 ° C. Synthesis example 4 Synthesis of triarylamine compound (Exemplified compound (216)) Stirrer, cooling tube, nitrogen introducing tube Equipped with a dropping funnel
Magnesium metal 2.9 g (0.12
(mol) was added and nitrogen substitution was performed. Then, 300 ml of dry diethyl ether was added and stirring was started. There, screw-
100 ml of a diethyl ether solution containing 61.1 g (0.1 mol) of 4,4 '-[(p-chloromethylphenyl) phenylamino] stilbene was slowly added dropwise. When about 10 ml was dropped, a gentle reflux started. While refluxing, the diethyl ether solution was further added dropwise, and after completion of the addition, the mixture was refluxed for 1 hour. The Grignard reagent solution obtained as described above is returned to room temperature, and then cooled there under ice,
13 g of dry ice was slowly added. After all the dry ice was added, the reaction mixture was stirred for 2 hours at room temperature to age the reaction. Then, 100 ml of water was added dropwise under ice cooling for hydrolysis. The resulting mass was dissolved by adding 0.1N hydrochloric acid solution.
Next, the ether layer was extracted, washed twice with a saturated aqueous sodium hydrogen carbonate solution and twice with water, and then dried over anhydrous sodium sulfate. After drying, diethyl ether was distilled off to obtain a white solid. The white solid was recrystallized from ethanol to obtain 46.6 g (yield 74%) of a biscarboxylic acid derivative. Next, 46.6 g (0.074 mol) of this biscarboxylic acid derivative was dissolved by heating in 500 ml of n-butanol, 2 ml of sulfuric acid was added, and the mixture was refluxed for 5 hours. After that, the temperature was returned to room temperature, and the reaction mixture was poured into 2 liters of water. The white solid obtained was filtered and dried. This white solid was purified by a silica gel column,
Triarylamine compound (Exemplified compound)
(216)) was obtained in an amount of 45.6 g (83%).

Rf = 0.5 (ethyl acetate / n-hexane = 1/2) Melting point: 165.9 to 166.3 ° C. Example 1 5 g of X-type metal-free phthalocyanine, butyral resin (S-REC BM-2, manufactured by Sekisui Chemical Co., Ltd.) 5 g Was dissolved in 90 ml of cyclohexanone and kneaded in a ball mill for 24 hours. The obtained dispersion was applied onto an aluminum plate with a bar coater so that the film thickness after drying was 0.15 μm, and dried to form a charge generation layer. Next, 5 g of the triarylamine compound (Exemplified compound (10)) obtained in Synthesis Example 1 and 5 g of a polycarbonate resin (Lexan 131-111, manufactured by Engineering Plastics Co., Ltd.) were dissolved in 90 ml of dioxane, and this was first dissolved A charge transport layer was formed by coating the charge generation layer formed in Section 1 above with a blade coater so that the film thickness after drying was 25 μm and drying.

The electrophotographic photosensitive member thus produced was subjected to a cellophane tape peeling test in accordance with JIS Z 1522, and no peeling occurred. Next, an electrophotographic photosensitive member manufactured by the completely same method was used by using an electrostatic copying paper test apparatus EPA-8100 manufactured by Kawaguchi Electric Co., Ltd.
When charged with a corona voltage of −5.5 kV, the initial surface potential V ₀ was −760 V. The surface potential V ₂ after standing for 2 seconds in the dark became −740V. Next, when a semiconductor laser having an oscillation wavelength of 790 nm was irradiated to determine the half-dose exposure amount E _1/2 , it was 0.33 μJ / cm ² , and the residual potential V _R was −0.3 V. Then, after repeating the above operation 5000 times, V ₀ ,
V _2, E _1/2, was measured for V _R, respectively -750
V, -730 V, 0.33 [mu] J / cm < ² >, -1.3 V, and no crystal precipitation was observed until the end of the test after the preparation of the photoreceptor. Therefore, it was found that the performance of the photoconductor was not deteriorated and showed high durability.

Examples 2 to 10 Photoreceptors were prepared in the same manner as in Example 1 except that the compounds having the compound numbers shown in Table 1 were used as the charge transport materials, and their performances were evaluated. The results are shown in Table 1. The results are the same as in Example 1, and no peeling occurred in the cellophane tape peeling test.

[0079]

[Table 1]

Example 11 A photoconductor was prepared in the same manner as in Example 1 except that dibromoanthanthrone represented by the following formula (234) was used as a charge generating material instead of the X-type metal-free phthalocyanine, and an irradiation light source was used. The performance was evaluated in the same manner except that a halogen lamp having an illuminance of 5 lux was used instead of the semiconductor laser of 790 nm. As a result, the initial V ₀ , V
_2, E _1/2, V _R respectively -730 V, -710 V, 1.2
lux · sec, −0.5 V, V ₀ , V ₂ , E after 5000 times
_1/2, V _R, respectively -720 V, -700V, 1.2 lux · s
ec, -0.9 V, and no crystal precipitation was observed until the end of the test after the photoconductor was prepared. Therefore, it was found that the performance as a photoconductor is excellent and the durability is high.

[0081]

[Chemical 57]

Examples 12 to 18 Photoreceptors were prepared in the same manner as in Example 11 except that the compound having the compound number shown in Table 2 was used as the charge transport material, and the performance was evaluated. The results are shown in Table 2,
The result was similar to that of Example 11.

[0083]

[Table 2]

Comparative Example 1 A photoreceptor was prepared in the same manner as in Example 1, except that a triarylamine compound represented by the following formula (235) was used in place of the triarylamine compound represented by the compound (10). Was produced. However, when stored in the dark at 25 ° C. for one day, crystals of triarylamine-based compound began to precipitate. Using this product, performance evaluation was performed in the same manner as in Example 1. When charged with a corona voltage of −5.5 kV,
The initial surface potential V ₀ was −770V. The surface potential V ₂ after leaving for 2 seconds in the dark became −760 V. Then, a semiconductor laser with an oscillation wavelength of 790 nm is irradiated to halve the exposure amount E.
_{When 1/2} was obtained, it was 0.43 μJ / cm ² , and the residual potential V
_R was -56.8V. Next, after repeating the above operation 5,000 times, V ₀ , V ₂ , E _1/2 and V _R were measured and found to be −770 V, −750 V, 0.67 μJ / cm ² and −120.3 V, respectively. Was inferior in both sensitivity and durability.

[0085]

[Chemical 58]

Example 19 The same as Example 1 except that the triarylamine compound obtained in Synthesis Example 2 (Exemplified compound (64)) was used in place of the triarylamine compound obtained in Synthesis Example 1. To produce a photoconductor. The electrophotographic photoreceptor thus produced was subjected to a cellophane tape peeling test in accordance with JIS Z 1522, and no peeling occurred. Then Example 1 Results of the performance was evaluated in the same manner as the initial _{V 0, V 2, E 1/2} , V R respectively -720 V, -71
0 V, 0.28μJ / cm ^2, a -0.2 V, after 5000 times _{V 0, V 2, E 1/2} , V R respectively -710 V, -700
V, 0.28 μJ / cm ² , and -0.7 V. Further, after the photoconductor was prepared, no precipitation of crystals was observed until the end of the test.
Therefore, it was found that the performance as a photoconductor is excellent and the durability is high.

Examples 20 to 28 Photoreceptors were prepared in the same manner as in Example 19 except that the compound having the compound number shown in Table 3 was used as the charge transport material, and the performance was evaluated. The results are shown in Table 3,
The results were the same as in Example 19, and no peeling occurred at all in the cellophane tape peeling test.

[0088]

[Table 3]

Example 29 The same as Example 11 except that the triarylamine compound obtained in Synthesis Example 2 (Exemplified compound (64)) was used in place of the triarylamine compound obtained in Synthesis Example 1. A photoconductor was prepared in this manner, and the performance was evaluated in the same manner. As a result, initial V ₀ , V ₂ , E _1/2 , and V _R are −
760 V, −750 V, 1.1 lux · sec, −0.3 V, 50
V ₀ after 00 _{times, V 2, E 1/2, V} R , respectively -740
V, −730 V, 1.1 lux · sec, −0.7 V, and no precipitation of crystals was observed until the end of the test after the preparation of the photoreceptor. Therefore, it was found that the performance as a photoconductor is excellent and the durability is high.

Examples 30 to 36 Photoreceptors were prepared in the same manner as in Example 29 except that the compound having the compound number shown in Table 4 was used as the charge transport material, and the performance was evaluated. The results are shown in Table 4,
The result was similar to that of Example 29.

[0091]

[Table 4]

Comparative Example 2 A photoreceptor was prepared in the same manner as in Example 19 except that a triarylamine compound represented by the following formula (236) was used instead of the triarylamine compound represented by the compound (64). Was prepared and the performance was evaluated in the same manner. As a result, the initial _{V 0, V 2, E 1/2} , V R respectively -760
V, -740 V, 0.38μJ / cm 2, a -38.8V, after 5000 times _{V 0, V 2, E 1/2} , V R respectively -750 V, -7
The voltage was 40 V, 0.64 μJ / cm ² , and -81.6 V, and the sensitivity and durability of the photoconductor were inferior.

[0093]

[Chemical 59]

Example 37 The same as Example 1 except that the triarylamine compound obtained in Synthesis Example 3 (Exemplified Compound (102)) was used in place of the triarylamine compound obtained in Synthesis Example 1. To produce a photoconductor. The electrophotographic photoreceptor thus produced was subjected to a cellophane tape peeling test in accordance with JIS Z 1522, and no peeling occurred. Next, as a result of performing performance evaluation in the same manner as in Example 1, initial V ₀ , V ₂ , E _1/2 and V _R are −700 V and −69, respectively.
0 V, 0.25μJ / cm ^2, a -0.1 V, after 5000 times _{V 0, V 2, E 1/2} , V R respectively -690 V, -680
V, 0.25 μJ / cm ² , and -0.3 V. Further, after the photoconductor was prepared, no precipitation of crystals was observed until the end of the test.
Therefore, it was found that the performance as a photoconductor is excellent and the durability is high.

Examples 38 to 46 Photoreceptors were prepared in the same manner as in Example 37 except that the compound having the compound number shown in Table 5 was used as the charge transport material, and the performance was evaluated. The results are shown in Table 5,
The results were the same as in Example 37, and no peeling occurred at all in the cellophane tape peeling test.

[0096]

[Table 5]

Example 47 In the same manner as in Example 11 except that the triarylamine compound obtained in Synthesis Example 3 (Exemplified compound (102)) was used in place of the triarylamine compound obtained in Synthesis Example 1. A photoconductor was prepared in this manner, and the performance was evaluated in the same manner. As a result, the initial _{V 0, V 2, E 1/2} , V R are each -700 V, -680 V, 1.0 lux · sec, -0.3V, after 5000 times V _0, V _2, E _1/2, V _R, respectively -
It was 690 V, -670 V, 1.0 lux.sec, -0.8 V, and no crystal precipitation was observed until the end of the test after the preparation of the photoreceptor. Therefore, it was found that the performance as a photoconductor is excellent and the durability is high.

Examples 48 to 54 Photoreceptors were prepared in the same manner as in Example 47 except that the compound having the compound number shown in Table 6 was used as the charge transport material, and the performance was evaluated. The results are shown in Table 6,
The result was similar to that of Example 47.

[0099]

[Table 6]

Comparative Example 3 A photoreceptor was prepared in the same manner as in Example 37 except that a triarylamine compound represented by the following formula (237) was used in place of the triarylamine compound represented by the compound (102). Was prepared and the performance was evaluated in the same manner. As a result, initial V ₀ , V ₂ , E _1/2 , and V _R are −69, respectively.
0 V, −670 V, 0.30 μJ / cm ² , −42.3 V, 5000
V _0, V _2, E _1/2 after round, V _R respectively -680 V,
It was −670 V, 0.31 μJ / cm ² , and −93.6 V, and both the sensitivity and durability of the photoreceptor were inferior.

[0101]

[Chemical 60]

Example 55 The same as Example 1 except that the triarylamine compound obtained in Synthesis Example 4 (Exemplified compound (216)) was used in place of the triarylamine compound obtained in Synthesis Example 1. To produce a photoconductor. The electrophotographic photoreceptor thus produced was subjected to a cellophane tape peeling test in accordance with JIS Z 1522, and no peeling occurred. Next, as a result of performing performance evaluation in the same manner as in Example 1, initial V ₀ , V ₂ , E _1/2 and V _R are −770V and −760, respectively.
V, 0.20 μJ / cm ² , −0 V, V ₀ , V after 5000 times
_2, E _1/2, V _R respectively -760 V, -750 V, 0.20
It was μJ / cm ² and −0.3 V. Further, after the photoconductor was prepared, no precipitation of crystals was observed until the end of the test. Therefore,
It was found that the performance as a photoreceptor is excellent and that it exhibits high durability.

Examples 56 to 71 Photoreceptors were prepared in the same manner as in Example 55 except that the charge transporting materials having the compound numbers shown in Tables 7 and 8 were used, and their performances were evaluated. The results are shown in Tables 7 and 8, and the results are the same as in Example 55, and no peeling occurred at all in the cellophane tape peeling test.

[0104]

[Table 7]

[0105]

[Table 8]

Example 72 In the same manner as in Example 11 except that the triarylamine compound obtained in Synthesis Example 4 (Exemplified Compound (216)) was used in place of the triarylamine compound obtained in Synthesis Example 1. A photoconductor was prepared in this manner, and the performance was evaluated in the same manner. As a result, the initial _{V 0, V 2, E 1/2} , V R are each -760 V, -740 V, 0.9 lux · sec, -0.3V, after 5000 times V _0, V _2, E _1/2, V _R, respectively -
It was 750 V, -720 V, 0.9 lux.sec, -0.8 V, and no crystal precipitation was observed until the end of the test after the preparation of the photoreceptor. Therefore, it was found that the performance as a photoconductor is excellent and the durability is high.

Examples 73 to 80 Photoreceptors were prepared in the same manner as in Example 72 except that the compound having the compound number shown in Table 9 was used as the charge transport material, and the performance was evaluated. The results are shown in Table 9,
The result was similar to that of Example 72.

[0108]

[Table 9]

Comparative Example 4 A photoreceptor was prepared in the same manner as in Example 55 except that a triarylamine compound represented by the following formula (238) was used in place of the triarylamine compound represented by the compound (216). Was prepared and the performance was evaluated in the same manner. As a result, initial V ₀ , V ₂ , E _1/2 , and V _R are -67, respectively.
0 V, −640 V, 0.39 μJ / cm ² , −53.3 V, 5000
After the turn, V ₀ , V ₂ , E _1/2 , and V _R are -570 V, respectively.
It was −510 V, 0.52 μJ / cm ² , and −144.6 V, and the sensitivity and durability of the photoreceptor were inferior.

[0110]

[Chemical formula 61]

Claims (5)

[Claims] 1. A photosensitive layer provided on a conductive support, wherein the compound represented by the general formula (1): (Wherein Ar ₁ , Ar ₂ and Ar ₃ are the same or different and each represents an aryl group which may be substituted), and have one or more triarylamine skeletons, and At least one of the aryl groups has the formula-(CH ₂ ) _m --COOR (R
Represents an optionally substituted alkyl group, aralkyl group or aryl group, and m represents an integer of 1 or more and 6 or less. )
An electrophotographic photoreceptor containing a triarylamine compound substituted with an alkylenecarboxylic acid ester group represented by: 2. A triarylamine-based compound is represented by the general formula:
The electrophotographic photosensitive member according to claim 1, which is a compound represented by the formula (2). [Chemical 2] (In the formula, Ar ₄ , Ar ₅ and Ar ₆ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula — (CH ₂ ) _m —COOR (R And m have the same meanings as described above.) And are substituted with an alkylenecarboxylic acid ester group.) 3. A triarylamine compound is represented by the general formula:
The electrophotographic photosensitive member according to claim 1, which is a compound represented by (3). [Chemical 3] (In the formula, Ar ₇ , Ar ₈ , Ar ₁₀ and Ar ₁₁ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula — (CH ₂ ) _m — It is substituted with an alkylenecarboxylic acid ester group represented by COOR (R and m have the same meanings as above. Ar ₉ represents an optionally substituted arylene group.) 4. A triarylamine-based compound is represented by the general formula:
The electrophotographic photoreceptor according to claim 1, which is a compound represented by the formula (4). [Chemical 4] (In the formula, Ar ₁₂ , Ar ₁₃ , Ar ₁₆ and Ar ₁₇ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula — (CH ₂ ) _m — It is substituted with an alkylenecarboxylic acid ester group represented by COOR (R and m have the same meanings as described above.) Ar ₁₄ , Ar ₁₅
Are the same or different and each represents an optionally substituted arylene group. ) 5. The triarylamine-based compound has the general formula
The electrophotographic photoreceptor according to claim 1, which is a compound represented by the formula (5). [Chemical 5] (In the formula, Ar ₁₈ , Ar ₁₉ , Ar ₂₂ , and Ar ₂₃ are the same or different and each represents an optionally substituted aryl group, and at least one of the aryl groups has the formula — (CH ₂ ) _m — It is substituted with an alkylenecarboxylic acid ester group represented by COOR (R and m have the same meanings as described above.) Ar ₂₀ , Ar ₂₁
Are the same or different and each represents an optionally substituted arylene group. X is an oxygen atom, a sulfur atom, -CH ₂ - represents or -CH = CH-. )