JPS60243670A - Original printing plate for electrophotographic engraving - Google Patents

Abstract

PURPOSE:To enhance sensitivity and printing resistance, etc., by using a specified azo pigment as an electrostatic charge generating material to be added to a charge generating layer in an original printing plate for electrophotographic engraving having a photosensitive layer composed of the charge generating layer and a charge transfer layer. CONSTITUTION:The intended original printing plate for electrophotographic engraving is obtained by forming on a conductive substrate 1 an electrophotographic sensitive layer 2 composed of the charge generating layer 3 contg. an azo pigment represented by formula I, (A) being a coupler residue, such as formula II, and the charge transfer layer 4 contg. a charge transfer material, such as formula III and an alkali-soluble resin, such as a styrene-maleic anhydride copolymer. A good printing plate is obtained by uniformly charging this electrophotographic material, imagewise exposing it, developing the obtained electrostatic latent image with a toner, and heat fixing the toner image on the photosenstive layer 2, and dissolving off the nonimage part of the layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a novel printing plate that can be made by the Kuji photography method. More specifically, in a new printing plate containing a specific azo pigment, an electrostatic latent image obtained by charging and subsequent imagewise exposure is developed with toner, fixed to obtain a toner image, and then a non-image This invention relates to a printing plate that is made by eluting and removing a photosensitive layer.

BACKGROUND ART Conventionally, as master plates for lithographic printing, those using photosensitive resins or silver halide photosensitive materials have been known.

However, although lithographic printing plates using photosensitive resin have high printing durability, they have low sensitivity and cannot be used in so-called direct plate making, requiring the operation of creating a cinema negative or positive from a silver halide film from an original. However, there are drawbacks such as requiring extensive equipment and time-consuming plate making.

Further, although printing plates using diffusion transfer development or hardening development methods of silver halide photosensitive materials can be directly plate-made, they have the drawbacks of low printing durability and high cost per sheet.

Examples of printing plates for direct plate making using electrophotography include JP-B No. 47-47610 and JP-B No. 48-40.
002, Special Publication No. 48-18325, Special Publication No. 51-157
66 and Japanese Patent Publication No. 51-25761, a printing plate having a zinc oxide-resin dispersion system is known. After forming a toner image on this printing plate by electrophotography, it is treated with an acidic aqueous solution containing, for example, a ferrocyanate salt in order to make non-image areas hydrophilic. The printing plates made in this way are free from the mechanical pressure applied during printing and the photosensitive layer of the dampening solution.
Penetration into the conductive treatment layer causes peeling and destroys the hydrophilic layer on the surface, so its printing durability is 5,000 to 10
In addition, dye sensitization is performed on zinc oxide/resin dispersion printing plates to make them sensitive in the visible light region, but they are still practical in the long wavelength light region of 600 nm or more. Sensitivity is not shown. Therefore, there is a drawback that exposure cannot be performed using a low-output and inexpensive He-Ne laser or semiconductor laser.

On the other hand, Tokuko Sho 37-17162, Tokuko Sho 3g-7758
, JP 46-39405, JP 52-2437, JP 56-107246, JP 55-105254,
Japanese Unexamined Patent Publication No. 55-153948, Hemorrhoid Opening No. 55-16125,
JP-A-57-147656, JP-A-56-146145
, Japanese Patent Application Laid-Open No. 57-161863, etc., for example,
A layer consisting of an organic photoconductive compound and an alkali-soluble resin on a hydrophilic conductive support such as a grained aluminum plate, or a charge-generating pigment such as a cyanine pigment dispersed in an alkali-soluble resin. A printing original plate for electrophotolithography is shown in which a layer or a layer sensitized by adding an electron-withdrawing substance or an electron-donating substance to the dispersed layer is provided. This type of printing original plate is made by forming a toner image on the photosensitive layer using an electrophotographic method, and then eluting and removing the photosensitive layer in the non-image area with an alkaline solution. Although it has the advantage of producing printing plates, it has low sensitivity as a photoreceptor for electrophotography, resulting in slow platemaking speed and the need to use a high-output light source.

Purpose An object of the present invention is to solve the problems of the conventionally known printing original plates for electrophotographic engraving as described above, and to provide a printing original plate having particularly high sensitivity and high printing durability.

Structure The printing original plate for electrophotographic engraving of the present invention comprises a charge generation layer containing an azo pigment represented by the following general formula (1.) and a charge transport layer containing a charge transport substance and an alkali-soluble resin on a conductive support. It is characterized by being provided with an electrophotographic photosensitive layer consisting of two layers.

General formula (I) (A represents a coupler residue) The basic structure of the printing original plate for electrophotographic engraving of the present invention is shown in FIG.

Here, 1 is a conductive support, on which a charge-generating layer 3 and a charge transport layer 4 are laminated, and an electrophotographic photosensitive layer 2
is formed.

The charge generation layer 3 and the charge transport layer 4 can also be stacked upside down.

Examples of the azo pigment used in the charge generation layer 3 include compounds having a phenolic hydroxyl group such as phenols and naphthols, aromatic amino compounds having an amine group, and aminonaphthols having an amine group and a phenolic hydroxyl group. Alternatively, a compound having an aliphatic or aromatic enolic ketone group (active methylene group) is used, and preferably the coupler residue A has the following general formula (L(self)
, head, (v), (■, (6)).

[In the formula, R1 is hydrogen, an alkyl group, a phenyl group, or a substituent thereof; substituent, heterocyclic group or the like. 2 These substituents or -N= (wherein, R23 is a hydrocarbon ring group or a substituent thereof, a heterocyclic group or a substituent thereof, or a styryl group or a substituent thereof, R3 is hydrogen, an alkyl group , phenyl group, or a substituted product thereof; alternatively, R2 and R3 may form a ring together with the carbon atom to which they are bonded. Kaisho GO-243
670(3) (Formula (110 and R4 in the formula represent a substituted or unsubstituted hydrocarbon group.) (In the formula, R5 represents an alkyl group, a carbamoyl group, a carboxyl group or an ester thereof, and Ar, represents a hydrocarbon group or a substituent thereof; (wherein, R6 is a hydrocarbon group or a substituent thereof, Ar
2 represents a hydrocarbon ring group or a substituted product thereof. ) Examples of the hydrocarbon ring in XK in the general formula used in the present invention include a benzene ring and a naphthalene ring; examples of the heterocycle include an indole ring, a carbazole ring,
Examples of the hydrocarbon ring group for Y or R2, such as a penzofuran ring, include a phenyl group, a naphther group, an anthryl group,
Examples of heterocyclic groups such as pyrenyl group include bilinol group, naenyl group, furyl group, indolyl group, penzofuranyl group,
Examples of the ring that can be formed with a carbazolyl group, a nobenzofuranyl group, and R2 and R3 together with the carbon atoms to which they are bonded include a fluorene ring.

Furthermore, as a hydrocarbon group in R4-f or R6,
Examples include alkyl groups such as methyl, ethyl, probyl and bunal groups, aralkyl groups such as bensol, aryl groups such as phenyl, and substituted products thereof. R
Examples of the substituent on the hydrocarbon group of 4 or R6 include alkyl groups such as methyl group, ethyl group, zorobyl group, and pter group, alkoxy groups such as methoxy group, ethoxy group, propoxy group, and notoxy group, chlorine atom, and bromine atom. etc.−
- Examples include 9 atoms, hydroxyl groups, and nitro groups.

As a substituent on the phenyl group of R1 or the ring of
Or, as a substituent in the carbocyclic group or heterocyclic group of R2 or the ring that can be formed by R2 and R3,
Alkyl groups such as methyl group, ethyl group, probyl group, and puter group; alkoxy groups such as methquine group, ethoxy group, propoxy group, and ptoquine group; halogen atoms such as chlorine atom and bromine atom; Examples include noarkylamino groups such as alkylamino groups and nobennoramino groups, halomethane groups such as trifluoromethyl groups, ditro groups, cyan groups, carboxyl groups or esters thereof, hydroxyl groups, and sulfonic acid groups (SO3Na). Further, examples of the hydrocarbon ring group in Ar+ or Ar2 include a phenyl group and a naphther group, and examples of substituents in these groups include a methyl group,
Alkyl groups such as ethyl, probyl, and puter groups; alkoxy groups such as methoxy, ethoxy, propoxy, and butoxy; haloke/ni atoms such as nitro, chlorine, and bromine; cyano, and dimetelamino groups. , a soalkylamino group such as a soethylamino group, and the like.

The azo pigment used in the present invention is, for example,
7427, and is described in Japanese Patent Application Laid-Open No. 54-2738. Examples of these azo pigments are as follows.

Only the part A in the above general formula will be shown below.

The charge generation layer 3 is a layer mainly composed of an azo pigment represented by the general formula (1), but may contain a binder if necessary. In this case, the proportion of the azo additive in the charge generation layer is preferably 30% by weight or more. In order to prevent non-image areas from being eluted during the plate-making process, the printing original plate of the present invention uses a binder such as an alkali-soluble resin such as a sterene-maleic anhydride copolymer or a novolac type phenol resin. ) is preferable. However, it is also possible to use other resins as long as the proportion of the binder is small. In addition, the charge generation layer 3
The thickness is preferably 0.01 to 5 μm, more preferably 0.05 to 2 μm. If the thickness is less than 0.01 μm, charge generation will not be sufficient, and if it is more than 5 μm, the residual potential will be too high for practical use.

The charge transport layer 4 is formed of a charge transport substance and an alkali-soluble resin. Charge transport materials include hole transport materials and cage transport materials, and hole transport materials include, for example, 2
, 5-bis(4-diethylaminophenyl)-1.3.
4-Oxadiazole, 2,5-bis(4-(4-dietheraminosteryl)phenyl)-1.3.4-oxadiazole, 2-(9-ethylrubazolyl-3-)-
Oxanoazole compounds such as 5-(4-noethylaminophenyl)-1.3.4-oxadiazole, 2-vinyl-4-(2-chlorophenyl)-5-(4-noethylamino)oxazole'12- (4-noethylaminophenyl)-4-phenyloxazolnato oxazole compound, 1-phenyl-3-(4-noethylaminostyryl)-5-(4-noethylaminophenyl) hylasoline, 1 Pyrazoline compounds such as 1-phenyl-3-(4-nomethylaminostyryl)-5-(4-nomethylaminophenyl)pyrazoline, 2,2'-dimethyl-4,
4'-bis(dietheramino)triphenylmethane, 1
．． Diphenylmethane compounds such as 1-bis(4-nobennolaminophenyl)fluorene, tris(4-noethylaminophenyl)methane, 9-(4-nomethylaminobennolidene)fluorene, 3-(9 -fluorenylidene)-9-x telcarhasol; 9. Styryl anthracene compounds such as -(4-noethylaminosteryl)anthracene, 9-bromo-10-(4-noethylaminosteryl)anthracene,
, 2-bis(4-noethylaminosteryl)benzene,
Nosterylbenzene compounds such as 1,2-bis(2,4-dimethoxysteryl)penzene, 9-ethyl-rubazol-3-aldehyde I-meter-1-phenylhydrazone, 9-ethyl-rubazol-3-aldehyde Bennol-1-phenylhydrazone, 4-noethylaminobenzaldehyde 1,1-nophenylhydrazone, 2,
Hydrazones such as 4-nomethoxybenzaldehyde 1-benno-1-phenylhydrazone, 4-nonenylaminobenzaldehyde 1-methyl-1-phenylhydrazone {l[', 4-nophenylaminosterpene, 4-nobennolamino Stilbenes, stilbene compounds such as 4-#t+)ruaminostilbene, sterylnaphthalene compounds such as 1-(4-nophenylaminosteryl)naphthalene, 1-(4-sopennolaminostyryl)naphthalene, 4' monophenylamino-α-phenylsterpene, α-phenylstilpene compound of 4'-)tylphenylamino-α-phenylsterbenato, 3-steryl-9-ethylcarbazole, 3-(4-noethylamino)steryl-9 - A styryl carbazole compound such as ethyl carbazole is used.

Examples of the electron transport substance include chloranil, bromoanil, tetracyanoetherene, te1-ranoquinone dimethane, 2,4.7-}IJ nitro-9-7-fluorenone, and 2,4,5.7-tetranitro- 9-fluorenone, 2,4.5.7-tetranitroxanthone, 2,4
．． 8-trinitroteoxanthone, 2,6,8-trinitro 4H-indeno[1,2-b]theophene-4-
on, 1,3.7-}IJ nitronobenzotheophene-
Examples include 5-,5-nooxide.

The alkali-soluble resin used in the charge transport layer 4 refers to a resin that becomes soluble in an aqueous or alcoholic solvent by adding an alkali. For the purposes of the present invention, in addition to properties such as film-forming properties, electrical properties, and adhesion strength to a support, solubility properties are particularly important for these resins. Examples of resins having such characteristics include styrene-maleic anhydride copolymers, sterene-methacrylic acid/methacrylate copolymers, methacrylic acid/methacrylate copolymers, and phenol resins.

Phenomenore taJH effect ha, phenonole, O-
Cresol, m-cresol, p-cresol, ethylphenol, isoprobylphenol, t-7'terphenol, ty-mylphenol, hexylphenol, t-octylphenol, cyclohexylphenol, 3-methyl-4-chloro-6-t -pterphenol, inglovir cresol, ty tercresol, t
- at least one substituted phenol such as amyl cresol, hexyl cresol, t-octyl cresol and ncrohexyl cresol and formaldehyde;
It is obtained by condensing aldehydes such as acetaldehyde, acrolein, crotonaldehyde, and furfural under acidic conditions. A rack type resin is used.

The charge transport layer 4 is a layer mainly composed of a charge transport substance and an alkali-soluble resin, and the ratio of the charge transport substance in the layer is 10.
-70% by weight, preferably 20-60% by weight. When the proportion of the charge transport substance is below this range, almost no charge is transported, and when it exceeds this range, the mechanical strength of the layer is extremely poor and cannot be put to practical use. Further, the thickness of the charge transport layer 4 is 2 to 50 μm, preferably 3 to 20 μm. Below this range, the amount of charge is insufficient, and above this range, the residual potential becomes high and it takes time to elute the layer, making it impractical.

The charge transport layer 4 may contain a plasticizer.
Effective plasticizers include, for example, phthalic acid esters such as nometer phthalate, diether phthalate, and digtylphthalate, and glycol esters such as dimeter glycol phthalate and ethyl phthalyl ethyl glycolate.

These plasticizers can be contained within a range that does not deteriorate the electrostatic properties and alkali solubility of the photoconductive layer.

The conductive support 1 used in the present invention includes an aluminum plate, a zinc plate, a beaten copper-aluminum plate, a copper-stainless steel plate, a chrome-copper plate (D bimetal plate, a chrome-copper-aluminum plate, a chrome-lead iron plate, etc.) A conductive support having a hydrophilic surface such as a tri-metal plate such as a chrome-copper-stainless steel plate is used, and its thickness is 0.1 mm.
~1 m is preferred.

In particular, in the case of supports with aluminum surfaces, surface treatments such as graining, immersion in an aqueous solution of sodium silicate, potassium fluorinorconate, phosphate, etc., or anodizing are carried out. Preferably. As shown in U.S. Pat. No. 2,714,066, an aluminum plate was grained and then immersed in an aqueous sodium silicate solution.
After anodizing as shown in Publication No. 125,
Also preferred are those treated by immersion in an aqueous solution of alkali metal silicate.

The above anodizing treatment is performed by using an aluminum plate as an anode in an electrolytic solution consisting of a solution of an inorganic acid such as phosphoric acid, chromic acid, sulfuric acid, or boric acid, or an organic acid such as oxalic acid or sulfamic acid, or a salt thereof. It is carried out by passing an electric current.

In order to produce the electrophotographic printing plate of the present invention, first, the pigment represented by the general formula (1) and a binder, if necessary, are mixed with, for example, tetrahydrofuran, nooxane, nometerformamide, acetone, methyl ether, etc. Mix in an organic solvent such as ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethyl acetate, toluene, or siloxane hydrocarbon, and disperse using a ball mill, ultrasonic dispersion machine, etc. A uniformly dispersed coating solution is applied onto the conductive support and dried to form the charge generation layer 3. Next, acid load transport llfl
A solution prepared by dissolving an alkali-soluble resin and an alkali-soluble resin in the same organic solvent as above is applied onto the charge generation layer and dried to form the charge transport layer 4.

The plate making of the original printing plate for electrophotographic platemaking of the present invention is performed by first uniformly charging it in a dark place using a corona charger or the like, using a tungsten lamp, a Yaguchi Genranzo, etc.
Electrostatic discharge is performed by reflective exposure using a light source such as a xenon lamp or fluorescent lamp, close image exposure through a transparent positive film, or scanning exposure using a laser beam such as a He-Ne laser, argon laser, or semiconductor laser. A latent image is formed, this electrostatic latent image is developed with toner, and fixed by heating to obtain a toner image on the electrophotographic photosensitive layer (FIG. 2).

Next, when the printing plate on which the toner image has been formed in this way is immersed in an alkaline eluent, the electrophotographic photosensitive layer ('Ft charge generation layer and charge transport layer) in the non-image area not masked by the toner image is removed. is dissolved and removed, the hydrophilic surface of the conductive support is exposed, and only the toner image portion remains, making it possible to obtain a good printing plate (FIG. 3).

The eluent used here is, for example, an alkaline aqueous solution of inorganic salts such as sodium silicate, sodium phosphate, sodium hydroxide, and sodium carbonate, or an alkaline aqueous Q6 solution containing organic amines such as triethanolamine and ethylenediamine. A solution prepared by adding an organic solvent such as ethanol, benol alcohol, ethylene dalycol, or glycerin or a surfactant to these is used.

In the printing plate of the present invention, after the toner image is formed, the non-image area is dissolved and removed in the eluent, so the toner components include:
It is preferable that this eluate contains a resin component having resist properties.

This ml fat component may be anything that is insoluble in the eluate; for example, acrylic resin using methacrylic acid, methacrylic acid ester, etc., vinyl acetate buffing fat, vinyl acetate combined with ethylene or vinyl chloride, etc. Polymers, vinyl chloride resins, vinylidene chloride resins, vinyl acetal resins such as polyvinyl buteral, polystyrene, copolymers of sterene and ptanoene, methacrylic acid esters, polyethylene, polypropylene and their chlorides,
．． Polycarbonate, polyester resin, polyamide resin, phenolic resin, xylene resin, alkyd resin,
These include wax, polyolefin, and wax.

The printing original plate of the present invention may also contain a quinone dianodo compound or a noazo compound, such as 0-naphthoquinone noazodo, for the purpose of increasing the solubility of the electrophotographic photosensitive layer by full-surface exposure after toner image formation.

In the original printing plate of the present invention, after the plate-making process is completed, the conductive substrate with a hydrophilic surface is exposed in the non-image area, and the image area covered with the oleophilic toner remains. The ink adheres only to the image area, resulting in good printed matter without scumming.

Indeed, the printing plate of the present invention has % higher sensitivity than conventionally known printing plates (direct plate making is possible with various light sources such as He-Ne laser and semiconductor laser, and the printing plate obtained by this method is , has high shochu printing properties.

Next, the present invention will be explained in more detail with reference to Examples.

In addition, all "parts" in the examples represent parts by weight.

Example 1 1 part of Azoface Al was mixed with 0.0 parts of m-cresol-phenol copolymerized novolasoc resin (manufactured by Gunei Chemical Co., Ltd.: MP-707).
66.7 parts of a 74 wt% tetrahydrofuran solution was pulverized and mixed in a ball mill, and the resulting dispersion was applied onto a grained aluminum plate with a thickness of about 0.25 mm and heated at 80°C.
The mixture was dried for 10 minutes [2] to form a charge generation layer with a thickness of about 1 μm.

2,5-bis(
4-noetheraminophenyl)-1.3.41-year-old xadiazole 09, styrene-maleic anhydride copolymer (
A solution prepared by mixing and dissolving 1.8 parts (copolymerization molar ratio 1:1) manufactured by Aldrich Chemical Co., Ltd. and 132 parts of tetrahydrofuran was applied and dried at 80°C for 20 minutes to create a charge transport layer with a thickness of about 10 μm. A printing original plate for electrophotographic engraving of the present invention was prepared by forming layers.

This original printing plate was tested using an electrostatic copying paper tester (SP-428 model manufactured by Kawaguchi Electric Seisakusho Co., Ltd.).
After performing corona discharge of V for 20 seconds to make it negatively charged, it was left in a dark place for 10 seconds, and the surface potential V at that time. (volts), then irradiate the surface with light using a tungsten lamp so that the illumination intensity is 4.5 lux,
Its surface potential is V.

The half-reduced exposure amount Ey, . (looks/seconds) was calculated. The results are shown in Table-1.

Next, this original printing plate was applied to an electronic copying plate making machine (Ricoh S-1).
A clear toner image was formed on the charge transport layer by charging, imagewise exposure, development and fixing.

This original plate was mixed with 70 g of sodium metasilicate and 14 g of glycerin.
The electrophotographic photosensitive layer in the non-image area to which toner was not attached was removed by immersing it for 1 minute in a solution consisting of Qml, 550 rnl of ethylene glycol, and 150 ml of ethanol, and then washing it with a water jet while gently brushing it.

The printing plate made in this way is then printed on an offset printing machine (
When printing was carried out in a conventional manner using a printer (Model AP-1310 manufactured by Ricoh), more than 50,000 clear prints could be printed.

Examples 2 and 3 Electrophotographic engraving of the present invention was carried out in the same manner as in Example 1, except that the compounds shown in Table 1 were used as the azo pigment used in the charge generation layer and the charge transport substance used in the charge transport layer, respectively. A printing original plate was prepared, and ■o and Ey2 were measured.

The above results are shown in Table-1.

Example 4 1 part of azo pigment plate 1 was mixed with m-cresol-phenol copolymerization. 0.0 of lac resin (MP-707 manufactured by Gunei Chemical Co., Ltd.).
667 parts of a 74 wt% tetrahydrofuran solution was pulverized and mixed in a ball mill, and the resulting dispersion was mixed to a thickness of about 0.25 mm.
Coated on a grained aluminum plate and heated at 80°C.
This was dried for 10 minutes to form a charge generation layer with a thickness of about 1 μm.

On this direct load generation layer, 15 parts of 3-steryl-9-ethyl carharsol and m-cresol-phenol copolymerized novolak resin (Soei Kagaku-d:Ml''
-707) 3.0 parts and 120 parts of tetrahydrofuran were mixed and dissolved, and then applied at 80°C for 2 minutes.
A charge transporting layer having a thickness of about 10 μm was formed by drying at 00° C. for 10 minutes, thereby producing a printing original plate for electrophotolithography of the present invention. Regarding this printing original plate, V was used in the same manner as in Example 1. Table 2 shows the results of measuring E and E.

Next, a toner image was formed on the electrophotographic photosensitive layer of this printing original plate in the same manner as in Example 1, and then immersed in a solution of 25 parts of sodium metasilicate and 100 parts of water for about 45 seconds, and then lightly brushed with water. The electrophotographic photosensitive layer in the non-image area was removed by washing the plate while washing the plate, removing the electrophotographic photosensitive layer in the non-image area.

Examples 5 to 8 The electrophotographic plate of the present invention was prepared in the same manner as in Example 4, except that the compounds shown in Table 2 were used as the azo pigment used in the charge generation layer and the charge transport substance used in the charge transport layer, respectively. Create a printing master plate, v.

and E bar were measured.

The above results are shown in Table-2.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the basic structure of an original plate for electrophotographic engraving 811 of the present invention. Figures 2 and 3 are diagrams explaining the plate-making process of the seal notification 1j original plate of the present invention. Figure 2 shows a state in which a toner image has been formed, and Figure 3 shows a state in which a toner image has been formed, and Figure 3 shows a non-image area being eluted and removed. Indicates the state of 1... Conductive support, 2... Electrophotographic photosensitive layer, 3...
- Charge generation layer, 4... Charge transport layer, 5... Toner image. Procedural Amendment (Archive) September 27, 1980 Manabu Shiga, Commissioner of the Patent Office 1 1. Indication of the case 1982 Patent Application No. 99891 2. Name of the invention Printing original plate for electrophotographic engraving 3. Person making an amendment Related to the case Patent applicant address: 1-3-6 Nakamagome, Ota-ku, Tokyo 143 Name (
674) Ricoh Co., Ltd....Ichihaya representative Hiroshi Hamada 4. Date of amendment order (shipment date) August 28, 1980 5
．． Chemical formula of the specification subject to amendment 6. Contents of amendment (1) Specification pages 1, 5, 6, 7, 8, 12, 13, 14, 15, 16, 31 Page, engraving of the chemical formula on page 34, as shown in the attached sheet (no change in content)

Claims (1)

[Claims] An electronic device consisting of two layers, a charge generation layer containing an azo pigment represented by the following general formula (1) and a charge transport layer containing a charge transport substance and an alkali-soluble resin, on a conductive support. A printing original plate for electrophotographic engraving, characterized by being provided with a photosensitive layer. General formula (1) (However, in the formula, A represents a Kazolar residue.)