JPS5830759A - Electrophotographic receptor - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic receptor high in sensitivity and durability, by adding a specified bisazo pigment to a photoconductive layer, preferably, to the charge generating of a lamination type photoconductive layer. CONSTITUTION:An electrophotographic receptor has a photoconductive layer containing a bisazo pigment derived from 4,4'-diaminostilbene shown by the general formula in which X is an atomic group necessary to complete and optionally substd. aromatic hydrocarbon or hetero ring; R1 is H or alkyl; R2 is alkyl; R3, R4 are H, halogen, alkyl, alkoxy, NO2, or OH. This pigment is preferably added to the charge generating layer, and on this layer a charge transfer layer containing a charge transferring substance is laminated to make up an electrophotographic receptor, thus permitting this photoreceptor to have high sensitivity and long durability and to obtain an excellent copy.

Description

DETAILED DESCRIPTION OF THE INVENTION Regarding the electrophotographic photoreceptor of the present invention, further icI#1# includes:
Related to electrophotographic photoreceptors containing specific bisazo pigments Conventionally, electrophotographic photoreceptors made of inorganic photoconductive materials have been widely used, such as those using mori, selenium, cadmium sulfide, zinc oxide, etc.

On the other hand, electrophotographic photoreceptors made of organic photoconductive substances include photoconductive polymers typified by poly-N-vinylcarbazole and 2,5-bis(P-diethylaminophenyl)-1,3,4-oxygen. Products using low-molecular organic photoconductive substances such as Nasiazole, and products made by combining organic photoconductive substances with various dyes and pigments are known. Nine electrophotographic photoreceptors have excellent film properties and can be produced by coating, making it possible to provide extremely highly productive and inexpensive photoreceptors. Further, it has the advantage that color sensitivity can be freely controlled by selecting the sensitizer such as dye-pigment to be used, and a wide range of studies have been made to date. However, there are problems with sensitivity, durability, etc.
Only a few 0-shot I have been put into practical use so far.
! s□II's primary purpose is to provide an electrophotographic photoreceptor containing a specific bisazo pigment, and second, to provide a highly sensitive electrophotographic photoreceptor (in other words), and to provide M3 with high durability. The purpose of this invention is to provide an electrophotographic photoreceptor having a photosensitive layer containing at least Ill of a bisazo pigment represented by the following general formula (1). Coupled.

General formula [1] Halogen atom such as iodine atom, alkyl group such as methyl group, ether group, pgvir group, butyl group, amyl group, 2-
Human mixyethyl group, 2-methoxyethyl group, 2-methoxyethyl group, 2-, chloroethyl group, 3-hydroxypropyl group, 3-methoxyethyl group, 3-ethoxycuprobyl group, 4-hydroxybutyl group, 4-methoxybutyl group It can be substituted with a substituted alkyl group such as an ethoxy group, an alkoxy group such as an ethoxy group, a globoxy group, a butoxy group, an acyl group such as an acetyl group, a propionyl group, a butyryl group, a benzoyl group, a trioyl group, and the like. Examples of aromatic hydrocarbon rings include benzene ring and naphthalene ring; examples of heterocycles include indole ring and benzo 72
Examples include a carbon ring, a carbazole ring, and the like.

An island represents a hydrogen atom or an alkyl group, and an island represents an alkyl group. Specific alkyl groups include methyl group, ether group, n-gaviA-group, n-glythyl-1n-amyl group,
Preferable examples include a sulfur group, an n-octyl group, and the like.

B and melon are water: IAJ [child, halogen atom (e.g. 1 chlorine atom, bromine atom, iodine atom, etc.), alkyl group (e.g. methyl group, ethyl, ru, buyl group, butyl group). ), alkoxy group (methoxy group, ethoxy group, propoxy group, nitro group, or hydrogen group), representative of the bisazo pigment represented by the above general formula [1] An example is
It is as follows.

Bisazo Pigment 1 (2) These bisazo pigments can be produced, for example, by converting 4,4'-diaminostilbene into p-tetrazotization using a conventional method, and then coupling the corresponding coupler in the presence of an alkali, or by combining the diamine described above. Once the trazonicum salt is in the form of fluoroborate salt or double salt of zinc chloride, etc., it can be dissolved in an appropriate solvent such as N,N-dimethylformamide, dimethylsulfonate, etc. in the presence of an alkali. Kagutsu below
It can be easily manufactured by coupling with.

Next, regarding representative examples of bisazo pigments used in the present invention,
The synthesis method is shown below.

Synthesis example (for the bisazo pigment A (1) exemplified above) 4.4'-diaminostilbene 5.25F (0,025
Mok) 63ml water 151ml hydrochloric acid 13.24ml (0,
01S%#) Kll dissolution nine liquid, sodium nitrite & 54F
(0,015 mm, b) was dissolved in 10.6 mJKil of water and added dropwise over 5 minutes while maintaining the liquid temperature at 4.5 to 7°C, and then stirred at the same temperature for 30 minutes.

Next, 3-human is converted into xy-naphthalene-2-methyl chloride (1G, 57F (0,0!525%)).
and gastric Noda 16.8F ((142 mol) in 420 m of water
The above tetrazotized wave was added dropwise over 10 minutes to the 1K full solution while keeping the temperature of the solution at 4 to 10°C, stirred at the same temperature for 2 hours, and left overnight.
A dry pigment 12.81 was obtained by soxhleting with methyl ethyl lactone for 2.0 hours.

Yield: 81 Elemental analysis: Molecular formula Ca1HseNsOa Calculated value (4)
Analysis value C71927188 H4734,7O N13L25 13.28 Other bisazo pigments used in the present invention can be synthesized in exactly the same manner.

As an electrophotographic photoreceptor containing an organic pigment on a conductive layer, there is one in which nine layers are provided by dispersing a pigment in a binder on a conductive layer as disclosed in Japanese Patent Publication No. 11852-1667. 18545.4I open super 47-303.2
A layer in which a pigment is dispersed in a charge transporting medium comprising a charge transporting material as disclosed in 8K or a charge transporting medium comprising the material and an insulating binder (the binder itself may be a charge transporting material) is provided on the conductive layer. thing.

(2) Consisting of a conductive layer, a charge generation layer containing an organic pigment, and a charge transport layer as disclosed in Ill@49-105537.

(2) There are charge transfer complexes in which an organic pigment is added to a charge transfer complex as disclosed in Japanese Patent Publication No. 49-91648.

The electrophotographic photoreceptor of the present invention is characterized by containing a bisazo pigment represented by the general formula [1], and can be applied to any type of electrophotographic photoreceptor having such characteristics. In order to increase the transport efficiency of charge carriers produced by the photoabsorption of the bisazo pigment shown in (1), it is desirable to use it as a type of photoreceptor of type (1), (2) or (3). Furthermore, the charge carrier oIA biological function and transport function are separated, and the 90 type photoreceptor is the best in making use of the pigment O characteristics! It's so good.

Therefore, this 0 type electrophotographic photoreceptor will be explained in detail.0 The layer structure requires a spreading layer, a charge generation layer, and a charge transport layer, and the charge generation layer is either above or below the charge transport layer. However, in electrophotographic photoreceptors of the type that are repeatedly used, conductive layers, charge generation layers,
An adhesive layer can be provided as necessary for the purpose of improving adhesion with the charge transport layer.0 Metal plate or metal foil such as expanded aluminum as a conductive layer,
A sticky film on which a metal of the aluminum type is vapor-deposited, aluminum foil combined with paper, paper treated with electrical conductivity, etc. are used.

Effective materials for the adhesive layer include casein, polyvinyl alcohol, water-soluble ethylene-acrylic acid copolymer, and Nidoμcell 4-S O resin.The thickness of the adhesive layer is 0.1~
A suitable range is 5μ, preferably 0.5 to 3μ.

Apply the general formula (1) on the conductive layer or adhesive layer on the conductive layer.
) The bisazo pigment shown in ) can be made into fine particles, and it can be prepared without a binder or, if necessary, by dispersing it in a thick binder S liquid, and applying and drying it.
When dispersing the bisazo pigment, known methods such as ball construction and ato-two-item can be used, and it is desirable that the pigment particles have a size of 5 μm or less, preferably 2 tones or less, and most preferably 0.5 μm or less.

Bisazo pigments can be prepared using ammonia-based solvents such as ethylenediamine.
It is also possible to apply it by pouring it on.

The application method is a blade! Conventional methods such as ear barring, spraying, dipping etc. are used.

The thickness of the charge generation layer is 5μ or less, preferably 0.01 to 1
μ is desirable. When a binder is used in the charge generation layer, a large amount of binder may affect the sensitivity, so the ratio of the binder in the charge generation layer is preferably 80-40 or less.
Desirably less than 1.

The binder used is polyvinyl butyl,
Polyvinyl Ih acid, polyester, polycarbonate,
Various resins such as phenoxy resin, acrylic resin, polyacrylamide, polyand, polyvinyl pidgin resin, cellulose resin, urethane resin, epoxy resin, casein, polyvinyl alcohol, etc. are used.
l! A charge transport layer can be provided on the charge generation layer provided as a charge transport layer. If the charge transport material does not have a film-forming ability, a charge transport layer may be formed by dissolving the binder in an appropriate solvent, applying a solution of nine liquids in a conventional manner, and drying the mixture.

The charge transporting substances include electron transporting substances and hole transporting substances, and the electron transporting substances include polyanyl, pulmoyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-)linylene, etc. ) R-9-fluorenone,
2.4.5.7-tetranitro-9-dicyanomethylenefluorenone, 2.4 to 7-tetotunitroquinanthone,
There are charge transporting substances of the 2.48-trinitrotheoquinanthone group and polymerization of these electron-withdrawing substances.

Hole-transporting substances include pyrene, N-ethylcarbazole, N-inglovircarbasol, N-methyl-N-phenylcarbasol, N-3-methylidene-9-ethylcarbazole, and N-methylcarbazole.

/ N-diphenylhydradi-t-3-methylidene-9-ethylcarbazole, N,N-diphenyl/hydrazi%-3-methylidene-1O-ethyl 7/ Etthiazine, N,N-diphenylhydradi-t-3-methylidene-9-ethylcarbazole -1O-Ethylphenoxadi7,P-')ethylanobenzaldehyde)'-N.

N-diphenylhydrazone, P-diethylaminobenzaldehyde N-a-su7teruN-nof,enylhydrazone, P-bi09di)benzaldehyde-N,N-diphenylhytodisine, 1°3.3-)9
Methylindolenine-〇-aldehy)'-N, N-
Hydrazones such as diphenylbenzaldehyde-3-methylbenzthiazolinone-2-human2cine, 2,5-bis(p-diethylaminophenyl)-1,! , 4-oxidediazole, 1-phenyl-3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline, l-[quinolyl(
2))-3-(P-diethylaminostyryl)-5-(
P-diethylaminophenyl)pyrazoline, l-(pyridyl)]-3-(P-diethylaminostyryl)-5
-(P-diethylaminophenyl)pyrazoline, 1-(
6-Medoxyviridyl(2))-a-(p-jethi$ruannoste')k>-5-CP-diethylaminophenyl)pizzolin, l-[pyridyl(3)]-3-(P
-diethylaminostiri#) -s-(P-diethylaminophenyl)pyrazoline, 1-[Levidil (2)
]-a-(p-diethylaminosteryl)-5-(P-diethylamino 7eniiA-)pizzoline, l-(pyridyl (2), l-3-(P-diethylaminostyryl)-4
-Methyl-5-(P-diethylaminophenyl)pyrazoline, 1-[pyridyl(2))-3-(α-methyl-P
-diethylaminosteri#) -5-(P-diethylaminophenyl)pyrazoline, l-722-3-(P
-diethylaminostyryl)-4-mef-5-(P-
diethylaminophenyl)pizzolin, 1-72sI
-3-(α-benzyl-P-diethylaminosteryl)
-5-(P-diethylaminophenyl)pyrazoline, pyrazolines such as subμpi2zoline, 2-(P-diethyl7minosteryl)-6-diethylaminobenzoquinazole, 2-(P-diethylaminophenyl)-4- (
Oxinacy-# compounds such as P-diethylaminophenyl)-5-(2-chloro72nyl)oxazole, 2-(
Thiazole compounds such as P-diethylaminostyryl)-6-dietheranobenzothiazole, triarylmethane compounds such as bis(4-diethylamino-2-methylphenyl)-7xylmethane, 1,1-bis(4-N , N-dietheraζno-2-methyl7enyl)hebutane, 1,1. Milk 2-Tetotsu Chusu (4
-N,N-dimethylamino-2-methylphenyl)ethane and other polyarylalkanes, tri7ethylamine, poly-H-vinylcarbazole,
Polyvinylpyrene, polyvinylacridine, polyvinylacridine, poly-9-bierphenylantothene,
Examples include pyrene-formaldehyde resin and ethylcarbazole formaldehyde resin. The charge transport materials are not limited to the nine described herein, and when used, one type or a mixture of two or more charge transport materials can be used.

The thickness of the charge transport layer is 5 to 30 microns, preferably 8 to 20 microns.As the binder, acrylic resin, polystyrene, polyester, polycarbonate, etc. can be used. For the binder of the low-molecular hole-transporting substance, an O-hole-transporting polymer such as poly-N-vinylcarbazole, which is mentioned above, can be used as the binder. On the other hand, as a binder for a low-molecular electron-transporting substance, a polymer of electron-transporting monomers as described in US Pat. When the charge transport material is an electron transport material, it is necessary to positively charge the surface of the charge transport layer, and when exposed to light after charging, good electrons are generated in the charge generation layer in the exposed area and injected into the charge transport layer. Table 1i
lrK is reached and the positive charge is neutralized, the surface potential is attenuated and an electrostatic contrast is generated between the surface potential and the unexposed area.

A visible image can be obtained by developing the electrostatic latent image thus formed with a negatively charged toner. Either fix this directly, or transfer the toner image to paper or plastic film, etc.
3J images can be made and fixed.

(9) A method of transferring the electrostatic latent image on the photoconductor onto an insulating layer of transfer paper, developing it, and fixing it can also be used. Among the types of OLL developer, the developing method and fixing method can be any of the known methods. may be adopted, and is not limited to a specific one.

On the other hand, when the charge transport material consists of a hole transport material, it is necessary to negatively charge the surface of the charge transport layer. After charging, when exposed to light, nine holes are generated in the charge generation layer in the exposed area and nine holes are transferred to the charge transport layer. It is injected, reaches the l1 surface, neutralizes the negative charge, and causes attenuation of the surface potential, creating an electrostatic contrast at the threshold with the unexposed area. During development, it is necessary to use a positively charged toner, contrary to the case where an electron transport material is used.

The ■ type photoreceptor is made by adding a bisazo pigment represented by the general formula (1) to an insulating binder solution such as that used for the charge transport layer of the type ■ photoreceptor, dispersing it, applying it to a conductive support and drying it. can be obtained.

The ■ type photoreceptor is made by dissolving the charge transport material and the insulating binder used in the charge transport layer of the ■ type photoreceptor in an appropriate solvent, and then adding the bisazo raw material represented by the general formula (1). After dispersion, it is obtained by coating and drying on a conductive support.

■Type of photoreceptorHiro ■When the electron transport material and hole transport material described in Taig's photoreceptor are combined, a charge transfer complex is formed. It is obtained by adding a bisazo pigment, dispersing it, coating it on a conductive support and drying it.

In both photoreceptors, the pigment used is one-light absorbing OA.
Uses a combination of pigments to increase the sensitivity of good and bad light sources.
General formula [
1) A combination of two or more types of bisazo pigments t,
Alternatively, it is also possible to use a material selected from known dyes and pigments in combination with a charge generating material.

The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines, but also in a wide range of electrophotographic applications such as laser printers and CRT printers.

Next, the present invention will be explained according to examples.Example 1 Polyvinyl alcohol water s
ttim cloth drying to form a coating weight of 0.8f/GoO adhesive layer.

Next, polyester tree M (polyester adhesive 4
9.000-ji! II 1 min 20 s-, 1 ml of DuPont, USA was dissolved in 80 ml of tetrahydro 7 run, 5 t of bisazo pigment of the above-mentioned pigment A (1) was dispersed in the 9-box, and this dispersion was placed on the adhesive layer. The coating amount after drying was 0.2017 d to form a specific charge generation layer.

Next, 1-(pyridyl(2))-a-(p-diethera-denosteryl)-5-(P-diethylaminophenyl)
Virazoline 5f and polymethyl methacrylate resin (number average molecular weight 100,000) 5f1 were added to benzene 70rx*tllC
Dissolve and coat on the charge generation layer, and after drying, form a charge transport layer with an amount of 1 Lot/wt.

The electrophotographic photoreceptor prepared using this method was statically corona charged at 05 KV using a Kawaguchi Den*m* electrostatic copying paper tester Model 8P-428, and then 100 KV was charged in a dark place.
After being held for a second, it was exposed to light at 5 tug of H degree and the 4f' charging property was examined.

The initial potential is Vo(v) t *The potential holding rate for 10 seconds at the location is Rv(j@, the half-attenuation exposure amount is El/2 (tug
-m@c), the charging characteristics of each photoreceptor were investigated, and the results are shown in Table IK.

Example 2 On the charge generation layer prepared in Example 1, 447-dolinitro 9-fluorenone st and Boy-4.4' were added. -Dioxydiphenyl-2,2'-globan carbonate (molecular weight 300,000) 5 jF is 0 m! After drying 1IIk of 9 coating solution, apply it so that the coating amount of O becomes 101/ze, and dry it.

The electrophotographic photoreceptor thus prepared was subjected to charge storage measurement using the same method as in Example 1. At this time, the charging polarity was set to O. The results are shown in Table 2.

Table 2 Voe” 530 volts Rv: 86 volts: 11.21ux Φttec Examples 3 to 1
0 Polyvinyl alcohol aqueous solution is applied and dried on the aluminum surface of the Al TG-attached Mike film (coating amount L21/wtc)
@ Forming a layer.

Next, each bisazo pigment 5f shown in Table 3 below and butycool resin (butycool degree 63 mol 5) 21 were mixed with ethanol 9
After dissolving and dispersing with a solution of 5 m/g, it was applied to the aluminum surface of an aluminum-deposited mylar film to form a charge generating layer with a coating weight of 0.21 m/g after drying.

Next K1-7 22ru 3 (P-jechilua</styril)
-5-(P-sheteaminophenyl)virazoline 5f,
The polycarbonate resin 51 used in Example 2 was dissolved in 770 ml of Nato2Humano7), and Nine Waves was applied onto the charge generation layer and dried, followed by coating in the same manner as in Coating Example 1. The results are shown in Table 3. ◎Example 11 An ammonia aqueous solution of casein was applied and dried on a 100-thick aluminum plate to form a coating amount of tot7wto@adhesive layer.

Then 2-(P-1ethylamino7enyl)-4-(-dimetelannophenyl)-5-(2-thalol7enyl)
Oquinazole 51 and poly-N-vinylcarbazole 5F
(Number average molecular weight: 300,000) was added to Keto2hydrof2fufu0 and pigment LO1 of Mu(1>) was dispersed, and then Klkl was dried on the adhesive layer to give a coating amount of xxp/wt.

The electrostatic charge of the photosensitive member prepared in Example 011 was measured in the same manner as in Example 1, and the measured values were as follows. However, the charging polarity was set to ■. This result! 1l14.

Table 4 VO: +540 volts R: 83- El, /z: &9 1ux meeting @e Patent applicant Canon Co., Ltd.

Claims (1)

[Scope of Claims] An electrophotographic photoreceptor comprising a layer containing at least 1111 of a bisazo pigment represented by the following general formula [1]. General formula [1] (wherein, 0) indicates a hydrogen atom, an atom, an alkyl group, a 2x group, a nitro group, and a hydroxyl group.