JPS6017762A - Printing plate for electrophotographic plate making - Google Patents

Abstract

PURPOSE:To directly make a printing plate through the electrophotographic process and to enhance printing resistance by forming a layer composed essentially of a specified azo pigment and an alkali-soluble resin on a conductive substrate. CONSTITUTION:A conductive substrate is coated with a layer composed essentially of an alkali-soluble resin and an azo pigment represented by the formula in which A is a coupler residue. As the coupler of the formula, compds. having a phenolic OH group, such as phenols and naphthols, and an aromatic compds. having an amino group, etc. are used. As said alkali-soluble resin, a resin which is made soluble in an aq. or alcoholic solvent by addition of alkali, and, e.g. a styrene-maleic anhydride copolymer, is used, and for this resin, film forming property, electric characteristics, strength of adhesion to a substrate, and especially solubility characteristics, etc. are important. The printing plate of such a constitution is good in sensitivity and it can be directly manufactured by using various kinds of light sources, such as laser, and the obtained printing plate has a high printing resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a novel printing plate that can be made by electrophotography. More specifically, with a new printing plate containing a specific azo pigment, an electrostatic latent image obtained by charging and subsequent imagewise exposure is developed with toner and fixed to form a U l-toner image after 1!7. It relates to a printing plate that is made by dissolving and removing the photosensitive layer in the non-image area.

BACKGROUND ART Hitherto, lithographic printing Kawahara plates and the like have been known that use photosensitive 1J1 resin or silver halide photosensitive materials.

However, although the lithographic printing plate using photosensitive t'JIri1 resin has a high printing durability, it has low sensitivity and cannot be used for so-called die reflex 1 plate making. There are drawbacks such as the 8-step process involved, requiring manual setup, and the time it takes to make a plate.

In addition, printing plates based on the diffusion transfer η development and hardening development methods of silver halide-sensitive 11 can be used in Tyref 1-plate making, but they have the drawbacks of low printing durability and high cost per sheet. There is.

Printing plates for tie-left plate making using electrophotography include, for example, JP-B No. 47-47610 and JP-B No. 48-40.
002, Special Publication No. 48-18325, Special Publication No. 51-157
66.1y Publication No. 51-25761 is known as a printing plate based on the oxide 1()-resin content 11(system).This printing plate is used to form l~lunar by an electrophotographic method. , in order to make the non-imaged area hydrophilic, it is treated with an acidic aqueous solution containing, for example) Ll cocyanate. This J, printing plate made by
5. The photosensitive layer and the conductive treatment layer are peeled off by the penetration of water.
1 occurred and the hydrophilic layer on the surface was destroyed, so the printing durability was about 5,000-1000 sheets.

In addition, in oxidized 4■I resin fraction printing plates, dye sensitization is performed to provide sensitivity in the visible light region, or even if the long-wave irradiation region 11' (600 nm or more) has a sensitivity sufficient for practical use. Therefore, low power C and cheap l
There is a drawback that exposure cannot be performed with a -1e-Ne laser or a semiconductor laser.

Special Publication No. 37-17102, Special Publication No. 38-7758, Special Publication No. 4G-39405, No. 52-2437, No. 5
In the photoconductive compound-resin printing plate described in Japanese Patent No. 6i07246, for example, an electrophotographic photosensitive material in which a xathiazole compound or an oxazole compound is bound with an alkali-soluble resin such as a styrene-maleic anhydride copolymer. Installed on a grained aluminum plate
An electrophotographic photoreceptor was used, and after forming a retoner image on this photoreceptor by electrophotography, the non-image area was dissolved and removed using an alkaline bamboo BM solvent.
1 Ru.

Similar to zinc oxide-resin printing plates, such organic photoconductive compound-resin printing plates undergo dye sensitization to have sensitivity in the visible light region, but the sensitivity is lower than that of other electrophotographic photoreceptors. Compared to this, it is extremely unsatisfactory. In particular, 60
There is almost no sensitivity to long wavelength light of 0 nm or more,
It is not possible to perform imagewise exposure using a 1e-Ne laser or a semiconductor laser.

Purpose The present inventors have made extensive research to solve the problems of the conventionally known printing plates for electrophotographic engraving as described above, and as a result, have completed the present invention. It is.

The purpose of Hokomei is to create a printing plate for electrophotolithography that has high sensitivity and provides a sharp image source with no stains in non-image areas.
1- It consists in offering.

Another object of the present invention is to create a printing plate for electrophotographic engraving that can record a light source C of 1le-Ne Rayleigh or half-rolled Rayleigh (Φ). .

In terms of structure, the present invention is characterized in that a conductive support is provided with a covering layer containing an azo pigment represented by the following general formula and an alkali-soluble resin as main components. This is the printed version.

General formula (1) (where 1 and Δ) represent the J Tsubler residue - 0) Here, the coupler is, for example, a compound having a phenolic hydroxyl group such as phenols or naphthols, or an aromatic compound having an amino group. An amino compound, an amino group having an amino group and a phenolic hydroxyl group, or a compound having an aromatic phenol group or an aromatic phenol membrane group, is preferably used. The coupler residue △ or the following general formula (I[>, (II[
), (IV), (Vl, V[), (VW) (!T).

[In the formula, R1 is hydrogen, an alkyl group, or their 'Fi conversion group or sudyryl group or its substituted product, R3 is hydrogen,
Maikohai'flt19! One may represent 1, or R263J: and R31 may be bonded to the overlapping carbon atom and R7 may be formed. )] ([<, in formula (Il[), Carboxyl or Ar+ represents a carbocyclic group or one substituent thereof.
r2 represents a hydrocarbon ring group or a sample thereof. ) Examples of the hydrocarbon ring substituted for Examples of the hydrocarbon ring group for R2 include phenyl group, naphthyl group, anthryl group, pyrenyl group, and heterocyclic groups (3L, pyridyl group, boutonyl group, furyl group, indolyl group, henzofuranyl group, Carbazolyl group, dibenzofuranyl 4g
Examples of the ring that can be formed with R 2 l13 and 1 (3 is the carbon to which they are bonded) include a fluorene ring. Further R4 or 1. Examples of the hydrocarbon group in which 83< is methyl, methyl, propyl, propyl, etc., aralkyl groups such as benzyl, aryl groups such as phenyl, or n derivatives thereof. can. Examples of replacement groups in the hydrocarbon group of R4 or R6 include methyl group, alkyl group such as del group, propyl group, and ethyl group, alkoxy group such as methoxy group, 11-oxy group, propoxy group, butoxy group, and chlorine group. Examples of substituents on the phenyl group of R+ or the ring of In addition, substituents on the carbocyclic group or heterocyclic group of Y or R2, or the ring that can be formed by 1(2 and 3) include methyl group, ethyl group, propyl group, ethyl group, etc. Alkyl groups, methoxy groups, -oxy groups, propoxy groups, alkoxy groups such as propoxy groups, halogen atoms such as chlorine atoms, bromine atoms,
Dimethylamino group, diethylamide 7 group, etc.', dialkylamino group such as dibenzylamino group, dialkylamino group such as dibenzylamino group, heromethyl group such as 1-rifle JO methyl group, di1-0 group, cyano group, carboxyl group or its ester, hydroxyl group, sulfonic acid group (5O3Na), etc. Furthermore, the hydrocarbon i-ring group on Ar+ or Arz includes a phenyl group, a naphthyl group, etc., and the substituents on these groups include a methyl group, an ethyl group, a propyl group, an ethyl group. alkoxy groups such as alkyl groups, methoxy groups, ethoxy groups, propoxy groups, butoxy groups; halogen atoms such as chlorine atoms and bromine atoms; Illustrative examples include 1-ruaminofu 41 and the like.

The Izo pigment used in the present invention is, for example, JP-A-55-
It is described in No. 69148. Examples of these faces are as follows.

Common parts in the general formula are omitted, and △ is accepted.

Refers to a resin that becomes soluble in aqueous or alkaline agents by adding alkali-soluble 11 used in J. According to the present invention, these resins have four important characteristics in addition to properties such as film formation, film properties, and strength of the INJ neck to electrical carriers. J of C, eel 1b ↑ 1 is combined with resin, example λpo, soubrene-anhydride 1IltJI-polymerization (styrene-methacrylic acid noryl 1-copolymer, methacrylic acid-menote polymer and phenol) Resins, etc. - Nortonol resins include Fe0-cresol, m-cresol, p-creodylphenol, isojLl bilfue [-butylphenol, toamilf 1)
Contains 1'silfuranol, 1-2cubol, non-chlorohexylphenol, 3-methyl-6-[-purdylinol, isopropizole, dobutylcresol,
Obtained by condensing at least one substituted phenol such as t-amylul, he-4-silcresol, tomectylur J3, and cyclohexylcresol with an aldehyde such as formaldehyde, acetaldehyde, acrolein, chloroaldehyde, and furfural under acidic conditions. A novolak type resin is used.

The printing plate of the present invention may contain an electron-accepting compound or an electron-donating compound, mainly for the purpose of improving electrophotographic properties such as sensitivity.

Examples of electron-accepting compounds include phthalic anhydride, tetrachlorophthalic anhydride, tetrachlorophthalic anhydride,
Pyromellitic anhydride, mellitic anhydride, vinyl chloride,
2,4-dinitrochlorobenzene, 2,4-dinitro 1
Brombenzine, 4-nitrobiphenyl, 2,4.6-
1-Lini] ~ Roanisole, 4.6-Jiku1] Roux 1.
3-Dinito [coben, chloranil, bromoanil, 2,4.7-1-dinitro-9-furalene, 2,4
, 5.7-titranitro-9-fluorenone, tetracyanoethylene, te(~lacyanoquinone dimethane, 2,
4,5.7-titranitroki → nonton, 2,4.8-
1-Linitrodioxy → J-ton, 2, G, 8-1-Linitro-1-indeno[1,2-b]]diA phen-4-A 1,3. -5,5-diAkizide and the like are used.

Electron donation f! For example, one compound is 2,5-bis(4-diethylaminophenyl)-1,3,4-71
Kyridazole, 2. Fl-bis[4-(4-diethylaminostyryl)phenyl J-'1,3.4-Jxadiazole,2-(OTdercarbazolyl-3-)-
5-(4-diethylaminophenyl) -1,3,4-
A-1 such as 'J xadiazole: lydiazole compound, 2-vinyl-4-(2-crosif-1-yl)-5-
(4-Diedylno7mino)Δki1Jzole, 2-(4-
Axazole compounds such as diethylaminophenyl)-4-phenyl Axazole, 1-phenyl-3-(4-
pyrazoline compounds such as diethylaminostyryl)-5-(4-diethylaminophenyl)pyrazoline, 1-phenyl-3-(4-dimethylaminostyryl)-5-(4-dimethylaminophenyl)pyrazoline, 2.2
- Diphenylmethane compounds such as dimethyl-4,4-bis(di-earthyl-amino)triphenylmethane, 1,1-bis(4-dibenzylaminophenyl)propane, tris(4-diethylaminophenyl)methane, 9-(
4-dimethylaminobenzylidene) fluoreno, 3-
Fluorene compounds such as (9-FluA renylidene)-9-ethylcarbazole, styryl anthracene compounds such as 9-(4-diethylaminostyryl) anthracene, 9-bromo-10-(4-diethylaminostyryl)an 1-racene, 1 .Disdyrylbenpine compounds such as 2-bis(4-diethylaminostyryl)benzene and 1,2-bis(2,4-dimethoxystyryl)benzene;
9-Ethylcarbazole-3-artethyl 1-medyl-1-phenylhydrazone, 9-ethylcarbazole-
3-Aldehyde 1-benzyl-1-phenylhydrazone, 4-diedylaminobenzaldehyde 1,1-diphenylhydrazone, 2.4-dimethoxybenzaldehyde 1-benzyl-1-phenylhydrazone, 4-diphenylaminobenzaldehyde 1-spool-1 hydrazone compounds such as -FI nylhi 1-razone, 4-SchifI nylaminostilbene, 4-dibenzylaminoferbene,
4-di-1-lylaminomethylhene and other methyl l\ene compounds; 1-(4-diphenylaminostyryl)pnotalene; 1-(4-dibensylaminostyryl)naphthalene and other styrylnonotalene compounds; --Schiff Inylamino -α-phenylstilbene, 4--Medifurnylamino -α-phenylmethylhene, etc.
F1nilsmethiben compound, 3-styryl-9-1delcarbazole, 3-(4-di■delamino)styryl-
Styrylcarbazole compounds such as 9-ethylcarbazole are used.

Furthermore, the printing plate of the present invention can avoid containing a plasticizer. As a plasticizer, for example, dimethyl phthalate, di-1
Phthalic acid esters such as dilphthale-1 to dibutylnotare-1, and glycol esters such as dimethyl glycol phthalate and edyl phthalyl glycol 1- are effective.

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

The conductive substrate used in the present invention includes an aluminum plate, a zinc plate, a copper-aluminum plate, a copper-stainless steel plate, a bimetallic plate such as a 1-mu copper plate, a chromium-copper-aluminum plate, a chromium-lead-iron plate, etc. A conductive substrate having a hydrophilic surface such as a metal plate such as a chromium-copper-stainless steel plate is used, and its thickness is from 0.1 to
1 mm is preferred.

In particular, in the case of a support having an aluminum surface, surface treatments such as graining treatment, immersion treatment in an aqueous solution of sodium 1-lium silicate, potassium fluorozirconate, phosphate, etc., or anodizing treatment, etc. Those that have been treated are preferred. Furthermore, as shown in U.S. Pat. No. 2,714,066, an aluminum plate which is subjected to a graining treatment and then immersed in an aqueous solution of 1 to 3 lithium Kuey's acid;
It is also preferable to carry out lvl polar oxidation treatment and then immersion treatment in an aqueous solution of an alkali metal gyrate as shown in Japanese Patent No. 7-5125.

The above-mentioned anodizing treatment is carried out in an electrolytic solution consisting of a solution of an organic acid such as phosphoric acid, phosphoric acid, sulfuric acid, sulfuric acid, or an organic acid such as oxalic acid or sulfuric acid, or a salt thereof. Then, a current is passed through the aluminum plate as an anode.
It is carried out by

In addition, in the present invention, an alkali-soluble intermediate layer such as casein, polyvinyl alcohol, dirrellulose, phenol resin, styrene-maleic anhydride copolymer, polyacrylic acid, etc. is optionally provided between the conductive substrate and the photoconductive layer. ib+ can be applied to improve the adhesion of the photoconductive layer to the substrate or the electrostatic properties of the photoconductive layer.

The Azo M format used in the printing plate of the present invention contains an alkyl soluble resin and, if necessary, additives such as an electron-accepting compound or an electron-donating compound in the electrophotographic photosensitive layer. However, preferably it is dispersed in the resin, and usually it is incorporated into the photosensitive layer by this method.

In order to produce the printing plate for electrophotographic engraving of the present invention, a pigment represented by the general formula and an alkali-soluble resin are mixed, for example, with tetrahydrofuran, di-1:san, dimethylformamide, ace1-one, methylbutylketone. , Nisidilene glycol TX1-l [Tumedel ether, ethylene glycol monoethyl 1-thyl,! I12 is combined in an organic solvent such as butyl monoacid, ethyl acetate, toluene, or a halogenated hydrocarbon, and if necessary, an electron-accepting compound or an electron-donating compound is added, followed by a hole mill or an ultrasonic dispersion machine. Prepare a uniformly dispersed coating solution using a dispersion method such as
The resulting coating solution is applied onto the conductive support, if necessary, via the intermediate layer described above, and dried.

The amount of the azo pigment and alkali-soluble resin that form the electrophotographic photosensitive layer of the printing plate of the present invention is preferably 0.01 to 100 parts by weight of the alkali-soluble resin per 1 part by weight of the azo pigment. When adding a neutral compound or an electron sacrificial compound, these should be added at a rate of 0.0 to the azo pigment.
1 to 100 mol is preferable, and 0.01 to 40 mol to 1"I is preferable. 19=L=Thickness L of the electrophotographic photosensitive layer of the electroconductive substrate 1; 11 to jIOμ■1 is preferable, Particularly preferred is 1 to 15 μm.

Printing plates for plate making are made using standard electrophotographic methods, and are uniformly charged in the dark using a Corono charger, using a tungsten lamp, a halogen lamp, a non-fluorescent lamp, or a fluorescent lamp. Electrostatic latent images are created by performing reflection image n° light using a light source such as a fluorescent lamp, contact image exposure through a transparent positive film, or scanning exposure using a laser beam such as an l-18-Ne laser, argon laser, or semiconductor laser. This electrostatic latent image is developed with toner and fixed by heating to obtain a toner image on the electrophotographic photosensitive layer.

Next, when the printing plate on which the 1-toner image has been formed in this way is immersed in an alkaline eluent, the photosensitive layer in the non-image area that is not masked by the toner image is dissolved and removed, and the hydrophilic layer of the conductive substrate is removed. The surface is exposed and only the 1-toner image portion remains on the support surface, resulting in a good printing plate.

The eluent used here is, for example, a noflukaline aqueous solution of an inorganic salt such as sodium silicate, sodium phosphate, tutorium hydroxide, or sodium carbonate, or an alkaline aqueous solution containing organic amines such as triethanolamine or ethylenediamine, or an alkaline aqueous solution containing ethanol, A solution containing an organic solvent such as benzyl alcohol, ethylene glycol, or glycerin or a surfactant 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 an eluent. It is preferable that it contains.

This resin component may be one that is insoluble in the eluate (for example, methacrylic acid, acrylic resin using methacrylic ester, vinyl acetate resin, copolymer of vinyl acetate and ethylene or vinyl chloride, etc.). combination, vinyl chloride resin, dinylidene chloride resin, vinyl 7't tar resin such as polyvinyl butyral, polystyrene,
Examples include copolymers of styrene and butadiene, methacrylic acid esters, polystyrene, polypropylene and its chlorides, polycarbonates, polyester resins, polyamide resins, phenolic resins, xylene resins, alkyd resins, waxes, polyolefins, and waxes.

In the printing plate of the present invention, after the toner image is formed, the electrophotographic photosensitive layer is dissolved F/? For example, 0-
Quinonediazide compounds such as nano-1-quinonediazide or diazo compounds may also be included.

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

Further, according to the present invention, 1 g of printing plates can be obtained which have long printing durability, high sensitivity, and can be directly plate-made using various light sources such as laser light.

The photosensitive layer of the printing plate of the present invention can also be used in the production of wiring boards.

Next, the present invention will be explained more specifically than in Example 1.

Example 1 Azo pigment N0.1 1-weight styrene-maleic anhydride copolymer 5fl? ff 1 part Tetrahydrofuran 64 parts by weight The mixture having the above composition was sufficiently pulverized and mixed in a ball mill, and the resulting dispersion was grained to a thickness of about 0.25 mm.
and coated with a wire bar on an anodized aluminum plate, 1o.

It was dried for 20 minutes at a temperature of .degree. C. to produce a printing plate having an electrophotographic photosensitive layer with a thickness of 6 .mu.m.

This printing plate was tested using a DTi copy paper tester (Kawaguchi Electric Seisakusho, Model 5P-428) at +61 (v:
``[''] After being positively charged with no discharge for 10 seconds, it was exposed to tungsten light at an illuminance of 20 lux.

As a result, after 10 seconds, 1) the electric potential was 490 volts, and the half-exposure m was 28 lux seconds.
Imagewise exposure is carried out using a tank-density light source charged to 0 to 1, and the resulting electrostatic latent image is developed with a 1-color and heat-fixed to form a 1-screen image.

Next, the printing plate on which the toner image was formed was immersed in a 1% by weight aqueous solution of mono-lithium silicate, and then washed with water while gently brushing to remove the electrophotographic photosensitive layer in the non-image area.

The printing plates prepared in this manner were printed on a Ricoh A offset printing machine model R'-1310 according to a conventional method, and 50,000 sheets of very clear prints without background smearing were printed.

Example 2 Azoface tlN0.2 1 part by weight m-cresol formaldehyde resin 5 parts 2,5-bis(diethylaminophenyl) -1,3,4-;1 Quizadiazole 5 parts by weight Tetrahydrofuran 99 parts Mixture of the above composition The liquid was thoroughly ground and mixed using a ball mill, and the resulting dispersion was applied onto a grained and anodized aluminum plate with a thickness of 0.25 mm.
The plate was dried at 00° C. for 20 minutes to produce a printing plate having an electrophotographic photosensitive layer having a crotch thickness of about 6 μm.

With respect to this printing plate, the charging potential and half-decrease exposure amount were measured in the same manner as in Example 1. As a result, the charging potential was +510 volts, and the half-exposure M was 1 flux·sec.

Next, in the same manner as in Example 1, this printing plate was subjected to charging, imagewise exposure, development, and fixing to form a toner image, and the electrophotographic photosensitive layer in the non-image area was removed.

When printing was carried out in the same manner as in Example 1 using the printing plate made in this way, the results were very clear with no scuffing. 50,000 copies of printed matter were printed.

Example 3 Azo pigment N (1,91 mm parts methacrylic acid (8096>) / methacrylic acid (20%) 5 parts by weight 2.4.7-Dolini 1-9 parts -9-Flu A lenone 5 Part by weight Te1-Rahydrofuran 99 parts by weight The mixture having the above composition was sufficiently pulverized and mixed in a ball mill, and the resulting dispersion was coated on a grained and anodized aluminum plate with a thickness of 0.25 mm (15 L). /, 1
A printing plate having an electrophotographic photosensitive layer with a thickness of 7 μm was prepared by drying at 00° C. for 20 minutes.

The charging potential and half-decrease exposure amount of this printing plate were measured in the same manner as in Example 1 except that it was charged at -6, Ok V. As a result, the charging potential was -485 volts, and the half-exposure was 1i20 lux·sec.

Next, this printing plate was charged, image exposed, and exposed in the same manner as in Example 1.
A regular development process was carried out to form a dove image, and the electrophotographic photosensitive layer in the non-image area was removed.

When printing was carried out in the same manner as in Example 1 using the printing plate made in this way, 50,000 clear prints with no scuffing were printed.

Effects As explained above, the present invention has good sensitivity, allows direct plate making with a divine light source such as a laser beam, and the resulting printing plate has high rigidity resistance.

Patent applicant Rico Co., Ltd. Agent Patent Attorney Hidetake Komatsu Agent Patent Attorney Hiroshi Asahi

Claims (1)

[Claims] (1) A printing plate for electrophotolithography, characterized in that a layer containing an azo pigment represented by the following general formula (I) and an alkali-soluble resin as main components is provided on a conductive support. . General formula (1) <However, A represents a coupler residue. ) ((2)
In the azo face 1 represented by the general formula (1), A is represented by the general formula (In''=, or a substituent thereof, a heterocycle or a substituent thereof; Y is a hydrocarbon ring group or a substituent thereof; The phenyl group, or lζ, has no substituents, or
J, and R3 may form a ring together with the carbon atom to which they are bonded.'' [The printing plate for electrophotolithography according to claim (1). 3) In the azo pigment represented by the general formula (I)C, 8 is the general formula (I) Matabanyo (IV) (Formula (I[) J3yoU (IV) (7)R+L
J, fF? Represents a substituted or unsubstituted hydrocarbon. )
A printing plate for electrophotolithography according to claim (1). 4) J3 in the azo pigment represented by the general formula (I>), Δ
represents the general formula (V) (wherein R5 is an alkyl group, )j Rubamoyl J31 a carboxyl group or an ester thereof, and Ar+ represents a carbocyclic group or a substituted product thereof. ) The printing plate for electrophotolithography according to claim No. +11. (5! In the azo pigment represented by general formula (I), △
is represented by the general formula (vI) or <vi> (wherein R6 represents a hydrocarbon group or a substituent thereof, and 8 and 2 represent a hydrocarbon ring group or a substituent thereof). A printing plate for electrophotographic engraving as described in range fi+.