JPH0445449A - Electrophotographic sensitive body and electrophotographic apparatus and facsimile each using the same - Google Patents

Abstract

PURPOSE:To improve the generation or injection efficiency of electric carriers or both inside a photosensitive layer and to enhance sensitivity and potential stability at the time of repeated uses by using a disazo pigment specified in structure in the photosensitive layer. CONSTITUTION:The photosensitive layer of the electrophotographic sensitive body contains the disazo pigment represented by formula I in which each of Ar1 and Ar2 is independently an optionally substituted aromatic hydrocarbon ring or hetero ring; Z1 is an O or S atom or the like; R1 is H, alkyl, or the like; and each of A1 and A2 is independently a coupler residue having a phenolic OH. The electrophotographic sensitive body rotates around a shaft 1a as a center in a constant peripheral velocity in the arrow direction, subjected to uniform charging to a prescribed positive or negative potential on its circumference by a charging means 2 in the course of rotation, undergoes imagewise exposure L by an exposing means 3 to successively form electrostatic latent images in accordance with exposed images on the circumference, and they are developed with a toner by a developing means 4, and then, the toner images are transferred onto a transfer paper supplied by a transfer means 5 in synchronism with the rotation of the photosensitive body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor, and more specifically, an electrophotographic photoreceptor having a photosensitive layer containing a disazo pigment having a specific structure; The present invention relates to an electrophotographic device and a facsimile machine.

[Prior Art] Conventionally, inorganic photoconductive substances such as selenium, cadmium sulfide, and zinc oxide have been widely used as electrophotographic photoreceptors.

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-oxadi Those using low-molecular organic photoconductive substances such as azoles, and those in which such organic photoconductive substances are combined with various dyes and pigments are known.

Electrophotographic photoreceptors using organic photoconductive substances have good film-forming properties and can be produced by coating, so they have the advantage of providing extremely highly productive and inexpensive photoreceptors. Furthermore, it has the advantage that color sensitivity can be freely controlled by selecting the dyes and pigments used, and a wide range of studies have been conducted to date. In particular, recent developments have led to the development of functionally separated photoreceptors in which a charge generation layer containing an organic photoconductive dye or pigment is laminated with a charge transport layer containing the aforementioned photoconductive polymer or low-molecular organic photoconductive substance. Significant improvements have been made in the sensitivity and durability, which were considered to be shortcomings of conventional organic electrophotographic photoreceptors.

Azo pigments exhibit excellent photoconductivity, and compounds with various properties can be easily obtained by combining the amine component and coupler component, so many compounds have been proposed so far, such as Japanese Patent Publication No. 54-22834
Publication No. 116040/1983, Japanese Patent Application Laid-open No. 1983-116040
-70232, JP 60-131539, JP 61-2.15556, JP 61-2
This method is already known in Japanese Patent Application Laid-open No. 41763 and Japanese Patent Application Laid-Open No. 158561/1983.

However, electrophotographic photoreceptors using conventional disazo pigments are not necessarily satisfactory in terms of sensitivity and potential stability during repeated use, and only a few materials have been put into practical use. .

[Problems to be Solved by the Invention] The objects of the present invention are to provide a novel photoconductive material, an electrophotographic photoreceptor having practical high sensitivity characteristics and stable potential characteristics during repeated use; An object of the present invention is to provide an electrophotographic apparatus and a facsimile equipped with the electrophotographic photoreceptor.

[Means for Solving the Problems, Effects] The present invention comprises an electrophotographic photoreceptor characterized by having a photosensitive layer containing a disazo pigment represented by the following general formula (1) on a conductive support.

In the general formula, A r + and Ar2 are the same or different and represent a carbocyclic aromatic group or a heterocyclic aromatic group which may have substituents, and Zl is an oxygen atom, a sulfur atom, or a dicyanomethylene group. , R1 represents a hydrogen atom, an alkyl group, a halogen atom, a cyano group or a nitro group, and A
1 and A2 are the same or different and represent coupler residues having a phenolic hydroxyl group.

Specifically, A r + and Ar2 are groups obtained by removing two hydrogen atoms from a carbocyclic aromatic ring such as benzene, naphthalene, and anthracene, or furan, virolcarboxylic acid,
Examples include groups in which two hydrogen atoms are removed from a heterocyclic aromatic ring such as thiophene, pyridine, and pyrazine, and substituents include halogen atoms such as fluorine, chlorine, iodine, and odor, methyl, ethyl, propyl, and isopropyl. , alkyl groups such as butyl, alkoxy groups such as methoxy, ethoxy, propoxy, aryloxy groups such as phenoxy, nitro groups, cyano groups, dimethylamino, dibenzylamino,
Examples include amino groups that may have substituents such as diphenylamino, morpholino, piperidino, and pyrrolidino.

In R, examples of the alkyl group include methyl, ethyl, isopropyl, and butyl, and examples of the halogen atom include fluorine atom, chlorine atom, and bromine atom.

Preferred examples of the coupler residues having a phenolic hydroxyl group represented by A and A2 include residues represented by the following general formulas (2) to (6).

X・' (2) x general formula (2)
, (3) and (4), X is a polycyclic aromatic ring or heterocyclic ring such as a naphthalene ring, anthracene ring, carbazole ring, benzcarbazole ring, or dibenzofuran ring, which may be fused with a benzene ring and have a substituent. Represents the residues necessary to form.

Y in general formula (6) represents a divalent aromatic hydrocarbon group which may have a substituent or a divalent heterocyclic group containing a nitrogen atom in the ring, and specifically, 0-phenylene, 0-naphthylene, berinaphthylene, 1゜2-antrylene, 3,4-
Pyrazolediyl.

2.3-pyridinediyl, 4,5-pyridinediyl, 6
．． Examples include divalent groups such as 7-indazolediyl and 67-chiralindiyl.

R2 and R1 in general formulas (2) and (3) represent a hydrogen atom, an alkyl group that may have a substituent, an aryl group, an aralkyl group, or a heterocyclic group, and R, , and R are both nitrogen atoms. It may be combined with an atom to form a cyclic amino group containing a nitrogen atom in the ring.

R4 in general formula (4) represents a hydrogen atom, an alkyl group that may have a substituent, an aryl group, an aralkyl group, or a heterocyclic group.

R6 in general formula (5) represents a hydrogen atom, an alkyl group that may have a substituent, an aryl group, an aralkyl group, or a heterocyclic group.

Examples of alkyl groups in the above expression include methyl, ethyl, and propyl; specific examples of aryl groups include phenyl, naphthyl, and anthryl; aralkyl groups include benzyl and phenethyl; heterocyclic groups include pyridyl; Groups such as thienyl, carbazolyl, benzimidazolyl, and benzothiazolyl, and cyclic amine groups containing a nitrogen atom in the ring include virol, viroline, pyrrolidine, pyrrolidone, indole, indoline, carbazoleimidazole, pyrazole, pyrazoline, oxazine, and phenoxazine. .

Examples of substituents include halogen atoms such as fluorine, chlorine, iodine, and bromine; alkyl groups such as methyl, ethyl, and propyl; alkoxy groups such as methoxy and ethoxy; alkylamino groups such as dimethylamino and diethylamino;
Examples include a phenylcarbamoyl group, a nitro group, a cyano group, and a halomethyl group such as trifluoromethyl.

72 in general formula (2) represents an oxygen atom or a sulfur atom, and n represents 0 or l.

In addition, in the disazo pigment represented by the general formula (1), in the formula,
A pigment using a coupler in which A1 and A2 are general formulas (2), (3), or (4) and X is condensed with a benzene ring to form a benzcarbazole ring has an absorption range in the near-infrared region. Since it spreads to the vicinity of the region, it is also suitable as a charge generating material for semiconductor lasers.

Typical specific examples of the disazo pigment represented by the general formula (1) of the present invention are listed below, but the disazo pigment used in the present invention is not limited to these.

The specific structure of the exemplified pigment will be expressed by describing only the changed parts in the basic form.

Basic type 1 Exemplary pigment Ar+, Art Nisha Exemplary Pigment (2) Ar+ r　2 : Exemplary pigment Same as Exemplary pigment Ar A　　　　　　2 : Exemplary pigment (1) Same as Exemplary pigment A r +.

rz : Exemplary pigment (1) Same as Exemplary pigment (5) A　r　　　＋ 　r　x : Exemplary pigment (1) Same as Exemplary pigment Exemplary pigment Ar 　r　2 : Exemplary pigment (1) Same as Exemplary pigment Ar , Ar 2 d Jito Exemplary pigment -Hs H A　r　　　＋ 　r　t : Exemplary pigment (1) Same as Exemplary pigment (10) CHl leaf Ar A　　　　　　2 : Exemplary pigment (1) Same as Exemplary pigment (11) C,H! Ar rz : Exemplary pigment (1) Same as Exemplary pigment (12) A r +, 　r　2 : Exemplary pigment (1) Same as Exemplary pigment (13) Example H charge (14) Ar 　r　2 Two exemplary pigments (13) Same as Exemplary pigment (15) H Ar A　　　　　　2 ・Example pigments (l) Same as Exemplary pigment Exemplary pigment (17) Ar , Arz: with horses H3 Exemplary pigment (18) Ar 　r　2 : Exemplary pigment (1) Same as Exemplary pigment (19) Ar , Arx: Yen and Exemplary pigment (2o) Exemplary pigment (21) Exemplary pigment (22) Exemplary pigment (23) Ａ　　　　I　・ A　　　　　t : Exemplary pigment (1) Same as Exemplary pigment (24) Ar 　r　2 6 Exemplary Pigments (1) Same as Exemplary pigment (25) Exemplary pigment (26) Exemplary pigment (27) Ar A　　　　　　2 Exemplary pigment (1) Same as Exemplary pigment (28) Ar 　r　2 : Exemplary pigment (1) Same as Exemplary pigment (29) Ar 　r　x : Exemplary pigment (1) Same as Exemplary pigment (30) Ar.

Art : Exemplary pigment (1) Same as Exemplary pigment (31) Ar Art : Exemplary pigment (1) Same as Exemplary pigment (32) Ar+% Art : Exemplary pigment (1) Same as Exemplary pigment (33) A　　　　　1〜 rz Two exemplary pigments (1) Same as Exemplary pigment Ar rz : Exemplary pigment Same as Exemplary pigment (35) Ar+, Art:+ :Chlorine atom Exemplary pigment (36) Ar rz : Exemplary pigment (35) Same as :Chlorine atom Exemplary pigment (37) Ar 　r　x : Exemplary pigment (35) Same as :　　　-CH* 38) with illustrative pigments Ar Ar　2 : Exemplary pigment (35) Same as : Bromine atom Exemplary pigment (39) : −c, +(ef) Exemplary pigment (40) Ar 　　r　2 : Exemplary pigment (35) Same as ・Bromine atom Example a paddy (4I) R -C-)1s Exemplary pigments (4) Exemplary pigment (43) r Art: (μ :　　　-CH.

Exemplary pigment (44) CH.

CH r Arz: 4 yam L :, -NO2 Exemplary pigment (45) so :Chlorine atom Exemplary pigment (46) CH.

r Arz ・Exemplary pigment (35) Same as ・Chlorine atom Exemplary pigment (47) r Arz : Exemplary pigment (35) Same as :Chlorine atom Exemplary pigment (48) Exemplary pigment (49) r 　r　2 Exemplary pigment (35) Same as fluorine atom Example surface It (50) r A　　　　　　2 Two exemplary pigments (35) Same as CH.

Exemplary pigment (51) Ar Ar.

:(to diatomic Exemplary pigment (52) A r +, Ar　2 : Exemplary pigment (5I) Same as :　　　-CH.

Exemplary pigment (53) Ar Ar　2 : Exemplary pigment (51) Same as :Hydrogen atom Exemplary pigment (54) Ar rz Exemplary pigment (51) Same as :Chlorine atom Example B fee (55) R+ :Hydrogen atom Exemplary pigment (56) :Hydrogen atom Exemplary pigment (57) :　　　-C,H.

Exemplary pigment (58) : Bromine atom Exemplary pigment (59) Ar 　r　x ≦ and :Hydrogen atom Exemplary pigment (60) C8゜ CH Ar A　　　　　　2 ・Exemplary pigment (59) Same as :Hydrogen atom Exemplary pigment (61) Exemplary pigment (62) CH.

Ar , A r 2 Exemplary pigment (51) Same as ・Bromine atom Exemplary pigment (63) Ar rz : Exemplary pigment Same as R diatomic Exemplary pigment (64) :Hydrogen atom Exemplary pigment (65) A r +, Ar.

: Exemplary pigment (51) Same as :　　　-CH.

Exemplary pigment (66) Ar Ar.

, Exemplary Pigment (51) Same as diatomic Exemplary pigment (67) Ar+, Art: diatomic Exemplary pigment (68) Ar Ar　2 : Exemplary pigment (67) Same as :　　　-CHI Exemplary pigment (69) Ar 　　r　2 : Exemplary pigment Same as :Hydrogen atom Exemplary pigment (70) Ar rz : Exemplary pigment [67] Same as : Bromine atom Exemplary pigment (71) ・Hydrogen atom Exemplary pigment (72) Ａ　　　　I　・ 　r　w : Exemplary pigment (67) Same as :Chlorine atom Exemplary pigment (73) :Hydrogen atom Exemplary pigment (74) fluorine atom Exemplary pigment (75) Ar A　　　　w Ear 2L R1 :Hydrogen atom Exemplary pigment (76) H Ar 　r　2 Two exemplary pigments (75) Same as Knee CJy (nl Exemplary pigment (77) R.

:Hydrogen atom Exemplary pigment (78) A r + ・ A　　　　　x : Exemplary pigment (67) Same as :Hydrogen atom Exemplary pigment (79) Ar+.

r 2 : Same as exemplified pigment: Hydrogen atom exemplified pigment (80) exemplified pigment (81) Ar+, Arz: Same R, knee No. as exemplified pigment (67) exemplified pigment (82) Ar1. Ar2: Same as exemplified pigment (67) R3: Hydrogen atom -M The disazo pigment represented by the formula (1) is obtained by tetrazotizing the corresponding diamine by a conventional method and coupling it with a coupler in an aqueous system in the presence of an alkali, or by combining it with a tetrazonium salt. is converted into a borofluoride salt or zinc chloride double salt, and then coupled with a coupler in an organic solvent such as N,N-dimethylformamide dimethyl sulfoxide in the presence of a base such as sodium acetate, triethylamine, or N-methylmorpholine. It can be easily synthesized by

A in general formula (1) 1. When synthesizing a disazo pigment in which A t is a different coupler residue, first 1 mol of one coupler is coupled to 1 mol of the above-mentioned tetrazonium salt, and then 1 mol of the other coupler is coupled. Either by synthesizing it, or by protecting one amine group of the diamine with an acetyl group, etc., diazotizing it and coupling it with one coupler,
It can be synthesized by hydrolyzing the protecting group with hydrochloric acid or the like, diazotizing it again, and coupling a coupler to the other side.

Synthesis Example (Synthesis of Exemplary Pigment (1)) 150m9 of water in a 300mε beaker! , concentrated hydrochloric acid 20 mρ
(0,23 mol) and 12.43 g (0,032 mol) were added and cooled to O'C. A solution of 4.6 g (0,067 mol) of sodium nitrite dissolved in 10 mI2 of water was cooled to 5 ml of water. It was dropped into the liquid over 10 minutes while keeping the temperature below ℃. After stirring for 15 minutes, carbon filtration was performed, and 10.5 g of sodium borofluoride (0
, 096 mol) in 90 m2 of water was soaked under stirring, and the precipitated borofluoride salt was collected by filtration, washed with cold water, washed with acetonitrile, and dried under reduced pressure.

Yield 13.88g, yield 74% Next, in II2 beaker, 500m+1 of N,N-dimethylformamide (DMF);! , and after dissolving and cooling the liquid temperature to 5°C, 11.7 g (0,020 mol) of the borofluoride salt obtained earlier was added.
and then 5.1 g of triethylamine (0,0
50 mol) was added dropwise over 5 minutes. After stirring for 2 hours, the precipitated pigment was collected by filtration, washed four times with DMF and three times with water, and then freeze-dried.

Yield 14.6 g, yield 78% Elemental analysis calculated value (%) Actual value (%) C75,6375,60 H3,873,95 N 11.96 11.87 The electrophotographic photoreceptor of the present invention has a conductive support. A photosensitive layer containing a disazo pigment represented by the general formula (1) is provided on the body. The form of the photosensitive layer may be any known form, but - a photosensitive layer containing a disazo pigment represented by formula (1) is used as a charge generation layer, and a charge transport layer containing a charge transport substance is added thereto. Laminated functionally separated photosensitive layers are particularly preferred.

The charge generation layer can be formed by coating a coating liquid in which the above-mentioned disazo pigment is dispersed together with a binder resin in a suitable solvent on a conductive support by a known method, and the film thickness thereof is, for example, 5 μm. Below, preferably 0
．． A thin film layer of 1 to 1 μm is desirable.

The binder resin used in this case is selected from a wide range of insulating resins or organic photoconductive polymers, including polyvinyl butyral, polyvinylbenzal, polyarylate, polycarbonate, polyester, phenoxy resin, cellulose resin, acrylic resin, polyurethane. etc., and the amount used is 8% in terms of content in the charge generation layer.
It is 0% by weight or less, preferably 40% by weight or less.

The solvent used is preferably selected from those that dissolve the resin described above but do not dissolve the charge transport layer or undercoat layer described below.

Specifically, ethers such as tetrahydrofuran and 1,4-dioxane, ketones such as cyclohexanone and methyl ethyl ketone, amides such as N,N-dimethylformamide, esters such as methyl acetate and ethyl acetate, toluene, xylene, Examples include aromatics such as chlorobenzene, alcohols such as metazole, ethanol, and 2-propanol, and aliphatic halogenated hydrocarbons such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichlorethylene.

The charge transport layer is laminated above or below the charge generation layer, and has the function of receiving charge carriers from the charge generation layer in the presence of an electric field and transporting them.

The charge transport layer is formed by dissolving a charge transport substance in a solvent together with an appropriate binder resin as necessary and coating the layer, and the film thickness is generally 5 to 40 μm, but 1
5 to 30 um is preferable.

Charge transport substances include electron transport substances and hole transport substances. Examples of electron transport substances include 24,7-dolinitrofluorenone, 2,4,5°7-titranitrofluorenone, chloranil, and tetracyanoquino. Examples include electron-withdrawing substances such as dimethane and polymerized materials of these electron-withdrawing substances.

Hole-transporting substances include polycyclic aromatic compounds such as pyrene and anthracene, carbazole-based, indole-based, imidazole-based, oxazole-based, thiazole-based, oxadiazole-based, pyrazole-based pyrazoline-based, thiadiazole-based, triazole-based compounds, etc. heterocyclic compound, p-
Hydrazone-based compounds such as diethylaminobenzaldehyde-N,N-diphenylhydrazone, N,N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, a-phenyl-4°-N,N-diphenylaminostilbene, 5-[ Styryl compounds such as 4-(di-p-tolylamino)benzylidene]-5H-dibenzo[a, dl cycloheptene, benzidine compounds, triarylmethane compounds, triphenylamine, or groups consisting of these compounds in the main chain or Examples include polymers having side chains (eg, poly-N-vinylcarbazole, polyvinylanthracene, etc.).

In addition to these organic charge transport materials, inorganic materials such as selenium, selenium-tellurium, amorphous silicon, and cadmium sulfide can also be used.

Further, these charge transport materials can be used alone or in combination of two or more.

When the charge transport material does not have film-forming properties, a suitable binder can be used. Specifically, insulating resins such as acrylic resin, polyarylate, polyester, polycarbonate, polystyrene, acrylonitrile-styrene copolymer, polyacrylamide, polyamide, and chlorinated rubber, or organic photoconductive resins such as poly-N-vinylcarbazole and polyvinylanthracene. Polymers and the like can be mentioned.

Examples of the conductive support on which the photosensitive layer is formed include aluminum, aluminum alloy, copper, zinc, stainless steel,
vanadium, molybdenum, chromium, titanium, nickel,
Indium, gold, platinum, etc. are used. Plastics (e.g. polyethylene, polypropylene,
Polyvinyl chloride, polyethylene terephthalate, acrylic resin, etc.) or conductive particles (e.g. carbon black, silver particles, etc.) are coated on a plastic or metal substrate with a suitable binder resin, or conductive particles are coated on plastic or paper. An impregnated support or the like can be used.

An undercoat layer having barrier and adhesive functions can also be provided between the conductive support and the photosensitive layer.

The undercoat layer can be formed of casein, polyvinyl alcohol, nitrocellulose, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, aluminum oxide, or the like.

The thickness of the undercoat layer is 5 μm or less, preferably 0°1 to 3 μm.
m is appropriate.

Another specific example of the present invention is an electrophotographic photoreceptor containing the above-mentioned disazo pigment and charge transport material in the same layer. At this time, poly-N was used as a 1f transport material.
- It is also possible to use charge transfer complexes consisting of vinylcarbazole and trinitrofluorenone.

The electrophotographic photoreceptor of this example can be formed by coating and drying a solution in which the above-mentioned disazo pigment and charge transfer complex are dispersed in a suitable resin bath solution.

A? used in any electrophotographic photoreceptor? 4 is a disazo pigment represented by the general formula (1). The crystal form of the disazo pigment may be amorphous or crystalline.
) It is also possible to use a combination of two or more types of disazo pigments, or to use them in combination with a known charge-generating substance.

The electrophotographic photoreceptor of the present invention can be used not only for electrophotographic copying machines, but also for laser beam printers, CRT printers, LED printers, liquid crystal printers, laser plate making,
It can also be widely used in electrophotographic applications such as facsimile.

Next, an electrophotographic apparatus and a facsimile equipped with the electrophotographic photoreceptor of the present invention will be described.

FIG. 1 shows a schematic configuration of a general transfer type electrophotographic apparatus using the drum type photoreceptor of the present invention.

In the figure, reference numeral 1 denotes a drum-type photoreceptor as an image carrier, which is rotated at a predetermined circumferential speed in the direction of the arrow around an axis 1a. During the rotation process, the photoreceptor l is uniformly charged to a predetermined positive or negative potential on its circumferential surface by the charging means 2, and then exposed to a light image by an image exposure means (not shown) in the exposure section 3, such as slit exposure or laser. beam scanning exposure, etc.).

As a result, electrostatic latent images corresponding to the exposed images are sequentially formed on the circumferential surface of the photoreceptor.

The static 1!4 image is then developed with toner by a developing means 4, and the toner developed image is transferred from a paper feed section (not shown) by a transfer means 5 between the photoreceptor 1 and the transfer means 5 as the photoreceptor 1 rotates. The images are sequentially transferred onto the surface of the transfer material P that is fed in synchronization.

The transfer material P that has undergone the image transfer is separated from the photoreceptor surface and introduced into the image fixing means 8, where the image is fixed and a copy is produced.
will be printed out on the outside of the aircraft.

After the image has been transferred, the surface of the photoreceptor 1 is cleaned by a cleaning means 6 to remove residual toner, and subjected to a charge removal process by a pre-exposure means 7, and is repeatedly used for image formation. As the uniform charging means 2 for the photoreceptor 1, a corona charging device is generally widely used. Further, as for the transfer device 5, a corona transfer means is generally widely used.

An electrophotographic apparatus is constructed by combining a plurality of components such as the photoreceptor and developing means cleaning means described above into an apparatus unit, and this unit is configured to be detachable from the apparatus main body. Also good. For example, the photoreceptor 1 and the cleaning means 6 may be integrated into one device unit, and configured to be detachable using a guide means such as a rail of the device body. At this time, the above-mentioned device unit may include a charging means and/or a developing means.

In addition, when an electrophotographic device is used as a copying machine or a printer, light image exposure involves scanning the reflected light or transmitted light from the document, or by reading the document and converting it into a signal. driving the array,
Alternatively, it is performed by driving a liquid crystal shutter array.

Furthermore, when used as a facsimile printer, the optical image exposure is exposure for printing received data.

FIG. 2 is a block diagram showing an example of this case.

A controller 10 controls an image reading section 9 and a printer 18.

The entire controller 10 is controlled by a CPU 16.

The read data from the image reading section is transmitted to the partner station through the transmitting circuit 12. Data received from the partner station is sent to the printer 18 through the receiving circuit 11. Predetermined image data is stored in the image memory. A printer controller 17 controls a printer 18. 13 is a telephone.

Images received from the line 14 (image information from a remote terminal connected via the line) are demodulated by the receiving circuit 11, and then the CPU 16 performs signal processing on the image information and sequentially stores it in the image memory 15. . Then, when the image of at least one page is stored in the memory 15, the image of that page is stored. The CPTJ 16 reads one page of image information from the memory 15 and sends out the one page of image information signaled to the printer controller 17 .

When the printer controller 17 receives one page of image information from the CPU 16, it controls the printer 18 to record the image information of that page.

Note that the CPU 16 receives the next page while the printer 18 is recording.

As described above, images are received and recorded.

[Example] Examples 1 to 20 A solution of 5 g of methoxymethylated nylon (weight average molecular weight 40,000) and 9 g of alcohol-soluble copolymerized nylon (weight average molecular weight 35,000) dissolved in 90 g of methanol was placed on an aluminum substrate using a Mayer tube. Applied with a bar, the film thickness after drying is lum
Form a subbing layer.

Next, add 5 g of exemplified pigment (2) to 90 g of cyclohexanone and add 2.5 g of butyral resin (butyralization degree 70 mol%).
g was added to the dissolved liquid and dispersed in a sand mill for 20 hours. This dispersion was applied onto the previously formed undercoat layer using a Mayer bar so that the film thickness after drying would be 0.2 um, and dried to form a charge generation layer.

Next, 5 g of a styryl compound represented by the following structural formula and 9 g of polycarbonate resin (weight average molecular weight 50,000) were dissolved in 70 g of tetralobenzene, and this was coated on the charge generating layer with a Mayer coating so that the dry film thickness was 17 μm. The electrophotographic photoreceptor of Example 1 was prepared by coating with a bar and drying to form a charge transport layer.

Example 2 using other exemplary pigments in place of exemplary pigment (2)
Electrophotographic photoreceptors corresponding to 2o were prepared in exactly the same manner.

The prepared electrophotographic photoreceptor was negatively charged with a corona discharge of 15 KV using an electrostatic copying paper tester Model 5P-428 manufactured by Kawaguchi Denki ■, held in a dark place for 1 second, and then charged with a halogen lamp. It was exposed to light at an illuminance of 16 lux and its charging characteristics were examined.

The charging characteristics include the surface potential (vo) and the amount of exposure required to attenuate the surface potential by half (El/2) after being left in the dark.
was measured. Show the results.

1 (2) 698 0゜2
(4) 697 0゜3
(5) 697 0゜4
(7) 700 0゜5
(11) 701 1゜6 (1
87001,19 7 (236981,1i 8 (277011,00 9(29) 699 0.9010
(31) 698 0.9111
(32) 700 1. 1
112 (346970,92゜13 (35) 699 0.9
714 (377010,95 15 (50) 700 1.0016
(516990,96 17(536980,93 18(666971,01 19(696991,00 20(767001,12) Comparative Examples 1-7 Comparative pigments (A)-( An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 1, except that G) was replaced, and the charging characteristics were evaluated in the same manner.The results are shown below.

comparative pigments (A) Comparison face It (B) comparative pigments (C) comparative pigments (D) comparative pigments (E) comparative pigments (F) comparative pigments (G) 12.

8゜ 9.

6 (F) 695 8
．． 77 (G) 698
9° 8 From these results, it can be seen that the electrophotographic photoreceptor of the present invention has sufficient charging ability and excellent sensitivity.

Examples 21 to 40 The electrophotographic photoreceptor prepared in Example 1 was used in an electrophotographic copying machine equipped with a -6.5 KV corona charger, an exposure optical system, a developer, a transfer charger, a static elimination exposure optical system, and a cleaner. Attached to the cylinder.

Initial dark potential■. and bright area potential■, respectively -700
The amount of variation in dark area potential (ΔVO) and the amount of variation in bright area potential (ΔVO) when the voltage is set at around -200V and used repeatedly 5,000 times.
ΔVL) was measured.

The electrophotographic photoreceptors prepared in Examples 2 to 29 were also evaluated in the same manner. Show the results.

Note that a negative sign in the potential variation amount represents a decrease in the absolute value of the potential, and a positive sign represents an increase in the absolute value of the potential.

+3 ten ten +2 = 4 3.

+ +1 + + 9 + 8 + 2 + 6 +2 = 1 + Comparative Examples 8 to 1 The electrophotographic photoreceptors prepared in Comparative Examples 1 to 7 were measured for potential fluctuations during repeated use in the same manner as in Example 21. . Show the results.

8 −× −×9
-76 +10110
-89 +9911
-56 +7312
-37 +3113
-49 +8714 -
101 +64× Due to poor sensitivity and large residual potential, initial settings could not be made. From the above results, it can be seen that the electrophotographic photoreceptor of the present invention has little potential variation during repeated use.

Example 41 A film thickness of 1.5 mm was deposited on the aluminum surface of an aluminum vapor-deposited polyethylene terephthalate film. A subbing layer of Oum's polyvinyl alcohol was formed. On top of this, the dispersion of the disazo pigment used in Example 4 was applied with a Mayer bar and dried, resulting in a film thickness of 0.2
A charge generation layer of .mu.m was formed.

Next, a solution prepared by diluting 5 g of a biphenyl compound having the following structural formula and 5.5 g of polycarbonate (weight average molecular weight: 50,000) in 40 g of tetrahydrofuran was applied onto the charge generation layer and dried to form a charge transport layer with a thickness of 16 um. .

The charging characteristics and durability characteristics of the produced electrophotographic photoreceptor were measured in the same manner as in Examples 1 and 21. Show the results.

Vo: 697V El/2: 1.39ux-sec △VD: 4V △VL: +11V Example 42 Electrophotography in which the charge generation layer and charge transport layer of the electrophotographic photoreceptor prepared in Example 16 were applied in the reverse order. A photoreceptor was prepared, and its charging characteristics were evaluated in the same manner as in Example 1. however,
The charging was positive.

Vo: +692V El/2: 1.4°C ux”sec Example 43 10 g of 3,5-dimethyl-3°,5°-di-tert-butyldiphenoquinone was placed on the charge generation layer prepared in Example 11. Polycarbonate resin (weight average molecular weight 30,000
1,000) 9.5g of chlorobenzene (70 parts by weight) -N,N
- A solution dissolved in 70 g of dimethylformamide (30 parts by weight) was applied with a Mayer bar and dried to a film thickness of 15 μm.
A charge transport layer was formed. The charging characteristics of the produced electrophotographic photoreceptor were evaluated in the same manner as in Example 1. However, the charging was positive.

Vo: +692V E 1/2: 3.5I2ux-sec Example 44 0.5g of exemplified pigment (13) was added to 79.5g of cyclohexano
The mixture was dispersed in a paint shaker with g for 5 hours. A solution prepared by dissolving 5 g of the charge transport material used in Example 1 and 5 g of the polycarbonate resin in 40 g of tetrahydrofuran was added to the mixture, and the mixture was further shaken for 1 hour. The coating liquid thus prepared was applied onto an aluminum substrate using a Mayer bar and dried to a film thickness of 20 mm.
A photosensitive layer of LLm was formed.

The charging characteristics of the produced electrophotographic photoreceptor were evaluated in the same manner as in Example 1. The charging was positive.

Vo: +697V El/2: 4.9nux-sec [Effects of the Invention] The electrophotographic photoreceptor of the present invention uses a disazo pigment with a specific structure in the photosensitive layer, thereby improving the efficiency of charge carrier generation inside the photosensitive layer. This has the remarkable effect of improving one or both of the injection efficiency and providing excellent characteristics in sensitivity and potential stability during repeated use.

This has the remarkable effect of reducing

Further, similar effects can be obtained when the electrophotographic photoreceptor is used in an electrophotographic apparatus and a facsimile.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a general transfer type electrophotographic apparatus. 1 is an electrophotographic photoreceptor, 2 is a corona charging device 3 is an exposure section, 4 is a developing means, 5 is a transfer means, 6 is a cleaning means, 7 is a pre-exposure means, 8 is an image fixing means, and L is a light image exposure ,
P is a transfer material that has undergone image transfer. FIG. 2 is a block diagram of a facsimile machine using an electrophotographic device as a printer. Reference numeral 9 is an image reading unit, 1o is a controller 11 is a receiving circuit, 12 is a transmitting circuit, 13 is a telephone, 14 is a line, 15 is an image memory, 16 is a CPU, 17 is a printer controller, and 18 is a printer.

Claims (1)

[Scope of Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer containing a disazo pigment represented by the following general formula (1) on a conductive support. General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (1) In the formula, Ar_1 and Ar_2 are the same or different and represent a carbocyclic aromatic group or a heterocyclic aromatic group which may have substituents, Z_1 represents an oxygen atom, a sulfur atom or a dicyanomethylene group, R_1 represents a hydrogen atom, an alkyl group, a halogen atom, a cyano group or a nitro group, and A_1 and A_2 are the same or different coupler residues having a phenolic hydroxyl group; represent. 2. The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer comprises at least two layers: a charge generation layer containing a disazo pigment represented by formula (1) and a charge transport layer. 3. An electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1. 4. A facsimile machine comprising an electrophotographic apparatus equipped with the electrophotographic photoreceptor according to claim 1 and a receiving means for receiving image information from a remote terminal.