JPH04125564A - Printing original plate for electrophotographic engraving and printing plate and production thereof - Google Patents

Abstract

PURPOSE:To improve electrophotographic characteristics, alkaline elutability and printing resistance by using a specific photoconductive compd. and a specific binder resin for the printing original plate. CONSTITUTION:This printing original plate is formed by using the zinc phthalocyanine of formula as the org. photoconductive compd. and a copolymer obtd. by polymerizing a monomer mixture composed of >=1 kinds of the compds. selected from hydroxyl alkyl (meth)acrylate, copolymerizable unsatd. carboxylic acid, styrene compd., and acrylate exclusive of the hydroxy alkyl acrylate as a binder, applying the photosensitive layer on a conductive base, then subjecting this layer to a heating treatment at 100 to 160 deg.C. In the formula, R denotes a -SZ group (Z denotes phenyl, the phenyl, naphthyl group, etc. sustd. with 1 to 5C alkyl group.)

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a printing original plate for electrophotographic printing, a printing plate obtained by exposing and developing the same, and a method for manufacturing the same. More specifically, the present invention relates to a printing plate precursor that is sensitive to semiconductor lasers and can be directly plated by electrophotography, a printing plate obtained by exposing and developing the same, and a method for manufacturing the same.

(Conventional technology) Due to technological advances in computer image processing and large-capacity data communication, images are processed by computers, and image information converted into digital signals is transmitted electronically via telephone lines, communication satellites, etc., and then sent to scanners on the receiving side. A new system has been proposed called electrotransmission printing, which prints by applying scanning exposure using a laser.

The conventional printing original plate for plate making is a method using photosensitive resin (P
S version method) is the mainstream. In the case of this PS plate method, the electronically transmitted information is written on a silver halide film, and then this film is closely exposed to the original printing plate for plate making, which requires large-scale equipment and takes time to make the plate. There is a problem. Furthermore, many PS plate type photosensitive materials require a large amount of exposure because they utilize photochemical reactions, and generally have low sensitivity. For this reason, the photosensitive material of the PS plate type also has the disadvantage that sufficiently satisfactory image information cannot be obtained by exposure with a low-output, inexpensive semiconductor laser.

In order to solve the above-mentioned problems of the PS plate method, a method using a silver halide photosensitive material as a printing original plate for plate making and a method using an electrophotographic method have been proposed, and some of them have been put into practical use. The former method has good sensitivity, but has the drawbacks of poor rigidity and high cost per sheet. On the other hand, the latter method has been actively researched in recent years because it allows direct plate making and has the potential to produce printing plates with relatively high sensitivity, low cost, and high rigidity resistance. There is.

In printing original plates for electrophotographic engraving, zinc oxide, organic compounds, and the like are used as photoconductive substances. Printing plates for plate making using zinc oxide are generally (A) easily smeared due to poor hydrophilicity of the non-image areas of the resulting printing plate; (B) mechanical pressure applied during printing and dampening solution. Penetration causes peeling of the photosensitive layer, so the resulting printing plate has poor rigidity.(c) Dye sensitization is performed to provide sensitivity in the visible light region, but it is still sufficient in the long wavelength region of 600n layers or more. However, it does not have high sensitivity, and has drawbacks such as difficulty in exposure with a semiconductor laser.

In the case of a printing original plate for plate making using an organic photoconductive compound, a photosensitive material in which the organic photoconductive compound is dispersed in a binder whose main component is an alkali-soluble resin is used, for example, on a grained aluminum plate. After forming a photosensitive layer on a substrate, a toner image is formed on this photosensitive layer by electrophotography, and the non-image area is dissolved and removed using an alkaline eluent to make a plate.

Many printing original plates for electrophotographic engraving have been proposed which are provided with a photosensitive layer in which an organic photoconductive compound is dispersed in an alkali-soluble resin. For example, JP-A-54-134,632, JP-A-55-105.254, JP-A-55-153,948.
In each of the publications, a phenolic resin is used as the alkali-soluble resin. However, when a phenol resin is used as a binder for an organic photoconductive compound, the film formed is fragile, and therefore has drawbacks such as poor rigidity.

JP-A No. 58-76.843, No. 59-147゜355
No. 60-17.752, No. 60-243.670
No. 62-198.864 and No. 64-23,2
In each publication No. 60, as an alkali-soluble resin,
A styrene-maleic acid copolymer is used. However, when a styrene-maleic acid copolymer is used as a binder for an organic photoconductive compound, the formed film is hard;
Curving the printing plate has drawbacks such as the tendency for cracks to occur. Acrylic resin is also widely used, and
No. 4-89.801 uses, for example, an aqueous acrylic resin as a binder and an ε-type crystalline copper phthalocyanine as an organic photoconductive compound. Images can be formed using these materials by electrophotography, but they have drawbacks such as not being easy to perform etching treatment with aqueous alkaline solutions, and not being able to be exposed to light in the near-infrared region using semiconductor lasers or the like.

In JP-A-56-146,145, an acrylic resin such as acrylic acid/methyl methacrylate/butyl acrylate copolymer is used as a binder, and a condensed polycyclic bovine noncontainer is used as an organic photoconductive compound. Methods using pigments and oxadiazole derivatives are disclosed. these are,
Etching treatment with an alkaline aqueous solution is easy, but the electrophotographic properties cannot be said to be fully satisfactory, and there are problems in that storage stability is poor. Furthermore, it also has the disadvantage that it cannot be exposed to light in the near-infrared region, such as with a semiconductor laser. Further, they have problems such as not being able to perform exposure in the near-infrared region such as a semiconductor laser, or even if it is possible, only insufficient electrophotographic properties can be obtained, resulting in poor printing properties.

JP-A-57-161,863, JP-A No. 58-145,49
No. 5, No. 63-136,052, No. 63-199.3
No. 59 and No. 64-31.165 use binders such as butyl methacrylate/methacrylic acid copolymer, styrene/2-ethylhexyl acrylate/acrylic acid copolymer, methyl methacrylate/ethyl methacrylate/methyl acrylate. A method is disclosed in which an acrylic resin such as / itaconic acid copolymer is used and a pyrazoline derivative, zinc oxide, or α-type phthalocyanine is used as a photoconductive material. All of these have drawbacks such as poor charging properties, poor printing properties due to insufficient alkali elution properties, low printing durability, and poor printing stability of printing plates. Further, they have problems such as not being able to perform exposure in the near-infrared region using a semiconductor laser or the like, or even if it is possible, insufficient electrophotographic properties are obtained, resulting in poor printing properties.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a novel printing original plate for electrophotographic printing, a method for manufacturing the same, and a printing plate obtained by exposing and developing the same. Another object of the present invention is to provide an improved printing original plate for electrophotographic printing and a printing plate for lithographic printing using an organic photoconductive compound, and a method for producing the same. Still another object of the present invention is to provide a printing original plate for electrophotographic engraving that is excellent in bipolar properties and alkali elution properties during electrophotography, a printing plate for lithographic printing that is excellent in printing properties, and a method for producing the same. Another object of the present invention is to provide a printing original plate for electrophotolithography that provides a printing plate with good storage stability and stiffness resistance. Still another object of the present invention is to provide a printing original plate for electrophotolithography having a photosensitive layer having excellent light resistance and weather resistance by using a binder that has good adhesion to the substrate and good mechanical strength; The purpose is to provide a manufacturing method. Another object of the present invention is to provide a printing original plate for electrophotographic engraving that has high sensitivity even in the near-infrared long wavelength region and can be exposed using a semiconductor laser or the like, and a method for manufacturing the same.

(Means for Solving the Problems) These objects are achieved by providing a printing original plate for electrophotolithography in which a photosensitive layer made of an alkali-soluble binder containing an organic photoconductive compound is provided on a conductive support. The organic photoconductive compound has a formula [wherein R is a -SZ group (
Z represents a phenyl group, a phenyl group substituted with an alkyl group having 1 to 5 carbon atoms, or a naphthyl group)], and the binder is (
a) at least one compound selected from the group consisting of hydroxyalkyl acrylates and hydroxyalkyl methacrylates, (b) at least one copolymerizable unsaturated carboxylic acid, (c) at least one styrene compound, and ( d) A copolymer obtained by polymerizing a monomer mixture consisting of at least one compound selected from acrylic esters other than hydroxyalkyl acrylate in (a), and the photosensitive layer is supported by an electrically conductive support. This is achieved by a printing original plate for electrophotographic engraving, which is coated onto a body and then heat-treated in a temperature range of 100 to 160°C.

These objects can also be achieved by a method for producing a printing original plate for electrophotolithography, which is characterized in that the photosensitive layer is coated on a conductive support and then heat-treated in a temperature range of 100 to 160°C. .

These objects can also be achieved by a printing plate for lithographic printing obtained by forming a toner image on the printing original plate for electrophotographic engraving by electrophotography, and after fixing, removing the non-image area by etching with an alkaline etching liquid. Ru.

(Function) The printing original plate for electrophotographic engraving according to the present invention has a photosensitive layer formed on a conductive column support, and the photosensitive layer has the following characteristics:
It consists of an alkali-soluble binder containing an organic photoconductive compound.

The organic photoconductive compound used in the present invention is a zinc phthalocyanine represented by formula I above. The zinc phthalocyanine has excellent electrophotographic properties among alkali-soluble binders, and does not interfere with alkali elution.

Specific examples of the zinc phthalocyanine represented by the above-mentioned formula (I) include the following. In addition, in any of the following compounds, the fluorine atom is 1.4.5.8.9. of the phthalocyanine nucleus represented by the following formula (II).
12. A total of 8 were introduced at the 13th and 16th positions. Please note that the words in brackets are abbreviations.

Octafluoro-octakis (phenylthio) zinc phthalocyanine [Fs (PhS)s ZnPc1 Octafluoro-octakis (0-tolylthio) zinc phthalocyanine [Fa (o-MePhS)a ZnPc co-octafluoro octakis (m-tolylthio) zinc Phthalocyanine [FB (m-MePhS)B ZnPc-octafluoro-octakis(p-tolylthio)zinc phthalocyanine [Fs (p-MePhS)B ZnPc]octafluoro-octakis(2,4-xylylthio)zinc phthalocyanine [Fs (2 ,4-MePhS)s ZnPc]octafluoro-octakis(2,3-xylylthio)zinc phthalocyanine [FB(2,3-MePhS)a ZnPc:]
]Octafluorooctakis0-ethylphenylthio)zinc phthalocyanine [FB (o-EtPhS)6 ZnPcoctafluorooctakis(p-ethylphenylthio)zinc phthalocyanine [Fa (p-EtPhS)a ZnPc]octafluoro -Octakis (0-isopropylphenylthio)
Zinc phthalocyanine [Fs (o-IPrPhS)s ZnPc] octafluoro-octakis (p-isopropylphenylthio) zinc phthalocyanine [Fs (p-IPrPhS)s ZnPc: 1 octafluoro-octakis (O-butylphenylthio) zinc phthalocyanine [ Fs (o-BuPhS)a ZnPc] octafluoro-octakis (m-butylphenylthio) zinc phthalocyanine [FB (m-BuPhS)6 ZnPc] octafluoro-octakis (p-butylphenylthio) zinc phthalocyanine [Fs (p- BuPhS)s ZnPc] octafluoro-octakis (p-tertiarybutylphenylthio) zinc phthalone anine [Fa (pt-Bu
PhS)sZnPc cooctafluorooctakis(naphthylthio)zinc phthalocyanine [Fs (NPhS)s ZnPc cooctafluorooctakis(naphthylthio)zinc phthalocyanine [Fs (NPhS)s ZnPc] Zinc phthalocyanine having the general formula I is, for example, 3.4, 5.6
- It can be produced in the following manner using titrafluorophthalonitrile as a starting material.

3.4.5.6-Titrafluorophthalonitrile is reacted with R8H,R in the presence of a condensing agent such as an alkaline substance (e.g. KF) in an organic solvent such as methanol or acetonitrile.
3.4.5.6-
Titrafluorophthalonitrile in which the 4- and 5-position fluorine atoms were previously substituted with functional groups was synthesized, and then the obtained substituents were introduced. Phthalonitrile and zinc powder or zinc halide are heated and melted or heated in an organic solvent to obtain the zinc phthalocyanine.

The binder used in the present invention includes (a) at least one compound selected from the group consisting of hydroxyalkyl acrylate and hydroxyalkyl methacrylate, and (b) at least one compound selected from the group consisting of hydroxyalkyl acrylate and hydroxyalkyl methacrylate. a polymerizable unsaturated carboxylic acid, (c) at least one styrene compound, and (d) at least one compound selected from acrylic esters other than hydroxyalkyl acrylate in (a), and optionally (e) ( It is a copolymer obtained by polymerizing a monomer mixture consisting of at least one compound selected from methacrylic acid esters other than hydroxyalkyl methacrylate in a).

The monomer (a) has a hydroxyalkyl group having 2 to 2 carbon atoms.
10, preferably 2 to 6 hydroxyalkyl acrylates and hydroxyalkyl methacrylates (hereinafter, acrylic acid and methacrylic acid are collectively referred to as "(meth)acrylic acid"). Specific examples of hydroxyalkyl (meth)acrylate include 2-hydroxyethyl (meth)acrylate, (
Examples include 2-hydroxypropyl meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, glycerol mono(meth)acrylate, trimethylolpropane (meth)acrylate, etc. .

The use of monomer (a) improves electrophotographic properties and durability as a printing plate. Moreover, a uniform and clean coating film can be obtained. This is the result of improved dispersibility by introducing a hydroxy group into the binder, which improves the adhesion of the binder to the conductive support and its affinity with the phthalocyanine of the present invention. it is conceivable that. It also has the effect of improving alkali etching properties, and can also lower the proportion of copolymerizable unsaturated carboxylic acid, which deteriorates electrophotographic properties when the proportion increases.

The proportion of monomer (a) used is 0.5 to 0.5 of the total monomer mixture.
40% by weight, preferably 2-25% by weight. If this proportion is less than 0.5% by weight or more than 40% by weight, the electrophotographic properties and durability of the printing plate will deteriorate, which is not preferred.

Monomer (b) is at least one copolymerizable unsaturated carboxylic acid. As this copolymerizable unsaturated carboxylic acid,
Monocarboxylic acids such as (meth)acrylic acid, dicarboxylic acids such as maleic acid, itaconic acid, and citraconic acid, and dicarboxylic acid monoesters such as monoisopropyl maleate. Saturated monomers can be used. Among these, (meth)acrylic acid and/or itaconic acid are preferably used. The proportion of monomer (b) used is 10 to 40% by weight, preferably 15 to 3% by weight of the total monomer mixture.
It is 0% by weight. If this usage rate is less than 10% by weight,
The alkali solubility of the resulting copolymer is low (and the etching rate is reduced). On the other hand, if it exceeds 40% by weight, the charging property is reduced and it becomes impossible to use it as a photosensitive layer.

In the copolymer used as a binder in the present invention, in order to obtain good etching properties, carboxylic acid is introduced into the copolymer to increase the acid value from 50 to 3001 g-KOH/
Adjust to within the g range. That is, by using the copolymerizable carboxylic acid in a specific proportion as described above, it is possible to improve the etching properties without impairing the electrophotographic properties.

Monomer (c) is a styrene compound. As the styrene compound, alkylstyrenes such as styrene, methylstyrene, ethylstyrene, and isopropylstyrene are preferably used, and styrene is particularly preferably used. The proportion of monomer (c) used is 10 to 70% by weight, preferably 25 to 55% by weight of the total monomer mixture. If the proportion used is less than 10% by weight, strength, affinity with phthalocyanine (dispersibility), and chargeability will decrease. On the other hand, if it exceeds 70% by weight, the proportion of monomers (a) and (b) decreases relatively, and the above-mentioned effects of using monomers (a) and (b) are lost, which is not preferable. .

The monomer (d) is at least one compound selected from acrylic esters other than hydroxyalkyl acrylate as monomer (a).

Specifically, the acrylic ester is an alkyl acrylate in which the alkyl group has 1 to 12 carbon atoms, preferably 2 to 8 carbon atoms, or a cycloalkyl acrylate in which the cycloalkyl group has 5 to 7 carbon atoms.

Specific examples of alkyl acrylate or cycloalkyl acrylate include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-propyl acrylate,
2-ethylhexyl acrylate, lauryl acrylate,
Examples include cyclohexyl acrylate and cycloheptyl acrylate. The proportion of alkyl acrylate or cycloalkyl acrylate used is 5 to 50% by weight, preferably 10 to 40% by weight of the total monomer mixture. If the ratio is within the above range, the lipophilicity can be increased, and the binding strength and flexibility of the resulting copolymer will also be increased, but if it exceeds 50% by weight, the monomer will be relatively Since the proportions of (a), (b) and (c) decrease, the above-mentioned effects of using monomers (a), (b) and (c) are lost, which is not preferred. In the present invention, the monomer (e) used as necessary is at least one compound selected from methacrylic acid esters other than hydroxyalkyl methacrylate monomer. Specifically, the methacrylic acid ester is an alkyl methacrylate in which the alkyl group has 1 to 12 carbon atoms, preferably 2 to 8 carbon atoms, or a cycloalkyl methacrylate in which the cycloalkyl group has 5 to 7 carbon atoms.

Specific examples of alkyl methacrylate or cycloalkyl methacrylate include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, 5ec-butyl methacrylate, and methacrylic acid. Examples include t-butyl, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, and cycloheptyl methacrylate. The proportion of alkyl methacrylate or cycloalkyl methacrylate used is 0 to 40% by weight of the total monomer mixture, preferably 15% by weight or less. If the usage ratio is within the above range, durability can be improved, but if it exceeds 40% by weight, the dispersibility with phthalocyanine becomes poor, which is not preferable.

Among the above monomer mixtures, a representative monomer mixture (p-1
) to (p-10) and their ratios are shown below.

(p-1) 2-hydroxypropyl acrylate/acrylic acid/styrene/butyl acrylate (5/20/35
/40 (weight ratio, same below)), (p-2) 2-hydroxyethyl methacrylate/methacrylic acid/styrene/butyl acrylate (2/23/40/35), (p-3) methacrylic acid -2-hydroxybutyl/acrylic acid/styrene/isopropyl acrylate (15/
25/45/15), (p-4) 3-hydroxypropyl methacrylate/acrylic acid/styrene/methyl acrylate/ethyl methacrylate (5/20/35/25/15), (p-5) Acrylic 3-hydroxybutyl methacrylate/methacrylic acid/styrene/isobutyl acrylate/isopropyl methacrylate (20/30/25/2015), (p-6) 2-hydroxyethyl methacrylate/methacrylic acid/styrene/propyl acrylate /ethyl methacrylate (5/25/40/2515), (p-7)-2-hydroxybutyl methacrylate/itaconic acid/styrene/butyl acrylate/methyl methacrylate (10/15/35/30/10) , (p-8)-3-hydroquinbutyl acrylate/acrylic acid/styrene/ethyl acrylate/butyl methacrylate (5/20/25/40/10).

There are no particular restrictions on the polymerization method for the above monomer mixture, such as bulk polymerization, solution polymerization, or suspension polymerization in the presence of a radical polymerization initiator such as peroxides, hydroperoxides, or azobisisobutyronitrile. 50 to 100°C, preferably 70 to 90°C by a conventional polymerization method.
It can be carried out at a temperature of The method of adding the monomer mixture can be appropriately selected, such as batch addition, divided addition, continuous addition, or a combination thereof.

The number average molecular weight of the copolymer obtained by polymerizing the above monomer mixture is 1.000 to 50,000, preferably 3.0
00-30.000.

A copolymer obtained by polymerizing the above monomer mixture, particularly a copolymer having a number average molecular weight within the above range, is soluble in an alkaline substance, and this copolymer is combined with the above photoconductive phthalocyanine. The photosensitive layer obtained by coating with the compound exhibits good alkali solubility and excellent etching properties.

The printing original plate for electrophotographic engraving of the present invention has a photosensitive layer formed by applying a coating liquid comprising the above-mentioned photoconductive phthalocyanine compound and the above-mentioned copolymer as a binder onto a conductive support.

There are no particular restrictions on the method for preparing the above coating solution; the binder (or photoconductive phthalocyanine compound) is dissolved or dispersed in a suitable solvent, and the photoconductive phthalocyanine compound (or binder) is dissolved in this. Alternatively, it may be prepared by dispersing it, or it may be prepared by dissolving or dispersing the binder and the photoconductive phthalocyanine compound in separate solvents, and then mixing the two. Solvents used to dissolve or disperse the binder and photoconductive phthalocyanine compound include aromatic hydrocarbons such as benzene and toluene, cyclic ethers such as tetrahydrofuran and dioxane, and halogen-containing solvents such as chloroform, dichloromethane and dichloroethane. Organic solvents such as hydrocarbons, acetone, ketones such as methyl ethyl ketone, esters such as ethyl acetate, and cellosolves such as methyl cellosolve can be used.

When preparing the above coating liquid, the photoconductive phthalocyanine compound is preferably used in an amount of 3 to 50% by weight, preferably 5 to 30% by weight of the binder.

In addition, the concentration of the photoconductive phthalocyanine compound and the binder dissolved or dispersed in the solvent is usually 0.5 to 5.
0% by weight, preferably 5-30% by weight.

The thickness of the photosensitive layer is preferably 2 to 10 μm, particularly 3 to 6 μm. If the film is thick, side etching is likely to occur during etching, and fine lines are likely to be scraped, which is not preferable. If the film thickness becomes thinner, the charging property will deteriorate, which is not preferable.

In the present invention, after forming the photosensitive layer on the conductive support, the temperature range is 100 to 160°C, preferably 110°C.
Heat treatment is performed in a temperature range of ~140°C. The purpose of heat treatment is to remove residual hydroxy groups derived from hydroxyalkyl acrylate or hydroxyalkyl methacrylate monomers and unsaturated carboxylic acid monomers in the copolymer obtained by polymerizing the above monomer mixture. This is because some self-crosslinking occurs between the carboxylic acid groups derived from the residues. By partially causing self-crosslinking, it is possible to improve the adhesion between the photosensitive layer and the conductive support, and as a result, it is possible to improve the printing durability during printing. At temperatures below 100°C, self-crosslinking is less likely to occur, and therefore the effect is less. Furthermore, if the temperature exceeds 160°C, self-crosslinking will proceed too much, resulting in poor alkali solubility, so that it cannot be used. That is, the objective is achieved by appropriately controlling self-crosslinking. The heating time varies depending on the temperature, etc., but is preferably in the range of 0.1 to 24 hours.

The coating solution for forming the above-mentioned photosensitive layer contains a polybasic acid organic compound, such as a compound represented by the following formulas (1), (2), and (V), as well as anhydrous amber. Electrophotographic properties can be further improved by containing at least one compound selected from acids and maleic anhydride as a sensitizer.

(In the formula, ~X5 Even if they are the same, or different hydrogen, hydrogen, and hydrogen, respectively. OH or -NO2).

Fluorine, 100 (in the formula, Y1 to Y4 may be the same or different, and each represents hydrogen, fluorine, -C00H or -
(represents NO2).

(In the formula, 21 to Z2 may be the same or different (respectively, hydrogen, fluorine, -COOH or -
(represents NO2).

Specific examples of these sensitizers include succinic anhydride, maleic anhydride, phthalic acid, tetrafluorophthalic acid, 4-
Nitrophthalic acid, phthalic anhydride, tetrafluorophthalic anhydride, 4-nitrophthalic anhydride, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, benzoic acid, pentafluorobenzoic acid, tetrafluorobenzoic acid etc. can be mentioned. Preferably, succinic anhydride, tetrafluorophthalic anhydride, benzoic acid,
pentafluorobenzoic acid and tetrafluorobenzoic acid, particularly preferably tetrafluorophthalic anhydride,
These are pentafluorobenzoic acid and tetrafluorobenzoic acid.

The sensitizer is 0.01 of a photoconductive phthalocyanine compound.
It is preferable to use it in a proportion of up to 10% by weight, preferably 2.0% by weight or less.

In addition, the coating liquid for forming the photosensitive layer may include oxazole derivatives, oxadiazole derivatives, pyrazoline derivatives, hydrazone derivatives, or triphenylamine derivatives in the photosensitive layer used after being charged with negative polarity. The properties of the electrophotographic photoreceptor can be further improved by incorporating a charge transfer substance and/or an aminotriazine resin.

As the charge transfer substance, it is preferable to use a hydrazone derivative represented by the following general formula VI.

(In the formula, R1 and R2 represent an aryl group or an aralkyl group, and R3 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a benzyl group, an alkoxy group having 1 to 4 carbon atoms, a phenoxy group, or a benzyloxy group. ) Specific examples of the hydrazine compounds represented by the above-mentioned formulas include the following.

(cT-2) (cT-3) (cT-4) (cT-5) (cT-6) (cT-7) (cT-9) (cT-11') (cT-12) (cT-13 ) As the aminotriazine resin, for example, melamine resin,
Benzoguanamine resin, acetoguanamine resin, CTU
Examples include guanamine resin (trade name, manufactured by Ajinomoto Co., Inc.) and cyclohexylcarboguanamine resin. In particular, it is preferable to use cyclohexylcarboguanamine resin.

Aminotriazine resin is an aminotriazine resin composition obtained by reacting aminotriazine with formaldehyde and optionally an alcohol such as butanol, that is, a methylolated product of aminotriazine.
The alkyl ether methylolated products may be used as they are or those obtained by appropriately dehydrating and condensing each of them. The charge transfer substance and/or the aminotriazine resin are preferably used in a proportion of 60% by weight or less, particularly 0.1 to 20% by weight of the photoconductive phthalocyanine compound.

The conductive support used in the present invention is not particularly limited, and commonly used aluminum plates, zinc plates,
or has a hydrophilic surface such as a bimetallic plate such as a copper-aluminum plate, a copper-stainless steel plate, a chrome-copper plate, or a tri-metallic plate such as a chromium-copper-aluminum plate, a chromium-copper-iron plate, a chrome-copper-stainless steel plate, etc. things can be used. The thickness of the conductive support is 0.05
~0.5m east is preferred.

In particular, in the case of supports with aluminum surfaces, those that have been subjected to surface treatments such as grain treatment, immersion treatment in aqueous solutions such as sodium silicate and potassium fluorozirconate, or anodization treatment. preferable.

The above anodic oxidation treatment can be performed using, for example, phosphoric acid, chromic acid, sulfuric acid,
This can be carried out by passing a current through an aluminum plate as an anode in an electrolytic solution consisting of a solution of an inorganic acid such as boric acid, an organic acid such as oxalic acid sulfamic acid, or a salt thereof. Furthermore, in the present invention, for the purpose of increasing rigidity, between the conductive support base material and the photoconductive photosensitive layer,
It is particularly preferable to provide an intermediate layer made of a resin having a composition within the scope of the present invention and having a higher acid value than the binder in the photosensitive layer.

There are no particular limitations on the plate-making method for the printing original plate for electrophotolithography of the present invention; it can be carried out by conventionally known methods. For example, first, according to the usual electrophotographic method, the film is uniformly charged in a dark place using a corona charger, and then exposed to a reflective image using a light source such as a tungsten lamp, a halogen lamp, a xenon lamp, or a fluorescent lamp. An electrostatic latent image is formed by contact image exposure through the lens, or by scanning exposure with a laser beam such as a He-Ne laser, argon laser, or semiconductor laser, and this electrostatic latent image is developed with toner and fixed by heating. , to obtain a toner image on the photosensitive layer.

The toner must be hydrophobic, ink-receptive, and have sufficient adhesion to printing plates to withstand printing, and must also have resistivity when etched with an alkaline aqueous etching solution. Further, as the electrophotographic developer, it is preferable to use a liquid developer which has better resolution than a powder developer. To meet these conditions, it is recommended to use toner containing styrene resin, acrylic resin, styrene-acrylic resin, styrene-methacrylic resin, polyester resin, epoxy resin, etc. as the resin in the liquid developer. good. Further, as the dispersion medium, there are organic solvents having a low dielectric constant and high electrical insulation properties, and it is preferable to use isoparaffin hydrogen carbonate, for example. In addition, pigments and dyes for coloring and charge control agents may be added to the extent that they do not adversely affect the safety or fixing properties of the toner, and the toner with a positive charge or the toner with a negative charge may be used depending on the purpose. It is better.

Next, when the printing plate for plate making on which the toner image has been formed 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 hydrophilicity of the conductive support is removed. Surface exposed 1. , only the image area of the toner image remains on the surface of the support, and the intended printing plate for lithographic printing can be obtained.

Examples of the alkaline eluent used to dissolve and remove the photosensitive layer in the non-image area include alkaline aqueous solutions of inorganic salts such as sodium silicate, sodium phosphate, sodium hydroxide, and sodium carbonate, triethanolamine,
An alkaline aqueous solution containing organic amines such as ethylenediamine, or a solution prepared by adding an organic solvent or a surfactant such as ethanol, benzyl alcohol, ethylene glycol, or glycerin to these aqueous solutions can be used. For example, an alkaline aqueous etching solution having the following composition is used.

EDTA-4H 4g Benzyl alcohol 30g Monoethanol 5g Dilute the total amount to 1 part with water
g Triethanolamine 60g + NaOH 25g The printing original plate for electrophotographic engraving can also be used as an electrophotographic photoreceptor for laser planer (OPC).

In a laser printer, the developed toner is transferred to paper and fixed on the paper.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Production Examples and Examples. Note that "part" and "%" mean "1 part by weight" and "% by weight" unless otherwise specified.

Production Example 1 [Production of Fs (PhS)s ZnPc] (1) Synthesis of starting materials 3.4. 5.6-Tetrafluorophthalonitrile 19. 6g (98 mmol), thiophenol 21.6g (196 mmol)
, 17.1 g (294 mmol) of potassium fluoride (KF), and 100 ml of acetonitrile were charged, and the mixture was reacted with stirring at 50° C. for 12 hours.

Thereafter, it was cooled to room temperature, the resulting yellow solid was filtered, and the resulting cake was purified by washing with methanol and then with warm water to produce 3,6-difluoro-4°5-bisphenylthiophthalonitrile 34 .5g (vs. 3.4.5.6-
Titrafluorophthalonitrile yield: 92.5 mol%)
I got it.

(2) Synthesis of Fs (PhS)e ZnPc 100m
10 g (26.2 mmol) of 3,6-difluoro-4,5-bisphenylthiophthalonitrile, 3.14 g (9.8 mmol) of zinc iodide, and 50 ml of benzonitrile were placed in a 4-tube flask, and then heated at 175°C.
The mixture was reacted with stirring for 6 hours. Thereafter, it is cooled and the resulting green solid is filtered, then methanol, benzene,
Wash with Soxhlet in order of acetone and FB (
PhS)s ZnPc (vs. 3,6-difluoro-4,
A yield of 5-bisphenylthiophthalonitrile (nearly 9.4 mol%) was obtained.

Production Example 2 [Production of Copolymer The copolymer can be produced, for example, as follows. After putting 40 parts of isopropanol as a solvent into a separable flask equipped with a stirrer, a temperature variable meter, a cooling tube, a nitrogen introduction tube, a monomer mixture dropping funnel, and a polymerization initiator dropping funnel, nitrogen was added from the nitrogen introduction tube. to create a nitrogen atmosphere inside the flask.

Next, 60 parts of the monomer mixture was charged into the monomer mixture dropping funnel 1, and 0.2 parts of azobisisobutyronitrile was charged into the polymerization initiator dropping funnel. The monomer mixture and polymerization initiator were added dropwise over 2 hours while adjusting the internal temperature of the flask to 80°C, and the mixture was further heated at 80°C for 2 hours, then at 85-90°C for 2 hours, and then cooled.

Example I FB (o-MePhS)B 1.5 parts of ZnPc, 0.05 parts of pentafluorobenzoic acid, monomer mixture (P'
12.0 parts of the copolymer obtained from -1) and 83 parts of dichloroethane were dispersed for 2 hours using a paint shaker disperser. The resulting dispersion was coated with a bar coater to a thickness of 0.15 mm.
It was coated on an aluminum plate that had been subjected to anodic oxidation treatment, dried with hot air at 60°C for 30 minutes, and then dried under reduced pressure for 1 hour.
Heat treatment was performed at 00°C for 2 hours and at 110°C for 3 hours to form a photosensitive layer. The thickness of the photosensitive layer at this time was 5 μm.

The single-layer electrophotographic photoreceptor thus obtained as a printing original plate for electrophotographic engraving was tested at +6. It was positively charged at OkV.

After that, after keeping it in a dark place for 5 seconds, it was exposed to white light (tungsten lamp) at an illumination intensity of 5 lux for 5 seconds.
Charging characteristics (surface potential (Vo), potential after being held for 5 seconds in the dark (V5), exposure amount required to attenuate the potential before exposure to 1/2 by exposure (E172) (
(Lux-sec)) and 780 nm monochromatic light separated by a spectral filter was irradiated at 0.5 μy/c-, and the half-life exposure energy sensitivity (μJ/cd) was determined.

Next, this single-layer electrophotographic photoreceptor was immersed in an aqueous solution containing 0.5% sodium hydroxide and washed with water to remove the photosensitive layer. The alkali elution property was determined based on the removal rate of the photosensitive layer at this time.

Next, the single-layer electrophotographic photoreceptor formed on the aluminum plate in this separately prepared grain chamber was plate-made by a liquid development method using a TTPS laser plate-making machine (manufactured by Toppan Printing Co., Ltd.). For corona charging, an electrostatic latent image was developed with a negative polarity developer at +6 kV and fixed by heating to form a toner image.

The formed toner image was washed out with an alkaline aqueous etching solution and washed with water to prepare a printing plate for lithographic printing.

The printing plate thus prepared was printed using an offset printing machine according to a conventional method, and the degree of scumming and the clarity of printing were evaluated at the initial stage and after printing 100,000 sheets.

Table 2 shows the results of the evaluation of the electrophotographic properties, alkali elution property, and printing performance.

Examples 2 to 17 In Example 1, FB (o-MePhS)sZn
Instead of the copolymer of Pc and the monomer mixture (p-1), a copolymer obtained from any of the photoconductive phthalocyanine compounds and monomer mixtures (P-1) to (P-8) shown in Table 1 can be used. A printing original plate for electrophotographic engraving was prepared in the same manner as in Example 1 except that the polymer and sensitizer were used and the heat treatment conditions and film thickness shown in Table 1 were used. and printing performance were evaluated, and the results are shown in Table 2. In addition, when the electrophotographic photoreceptor prepared above was left in a room with a fluorescent pair lit for two months and its electrophotographic characteristics and printing performance were measured, it was found that even after two months, There was no difference in performance.

Comparative Examples 1 to 6 In Example 1, FB (o-MePhs)BZ
In place of the copolymer of n P c and monomer mixture (P-1), a photoconductive phthalocyanine compound shown in Table 1,
Copolymers and sensitizers obtained from monomer mixtures of (P-1) to (P-8) or the following (S-1) to (S-5) produced in the same manner as Production Example 2 Example 1 except that the heat treatment conditions and film thickness shown in Table 1 were used.
The electrophotographic properties, alkali elution properties, and printing performance were evaluated in the same manner as above, and the results are shown in Table 2.

(S-1) (S-2) (S-3) (S-4) Acrylic acid/Butyl acrylate/ Butyl methacrylate (25/20155), Methacrylic acid/Styrene/ Isopropyl acrylate (30/15155), Methacrylic acid/Methyl acrylate/ ethyl methacrylate (15/60/25), Acrylic acid/Styrene/ (S-5) Ethyl acrylate/ Methyl methacrylate (25/8/20/47), Acrylic acid/Butyl acrylate/ Methyl methacrylate/ 2-hydroxyethyl methacrylate (10/40/40/10).

Examples 18 to 27 In Example 1, FB (o-MePhS)aZn
Instead of the copolymer of Pc and the monomer mixture (P-1), a copolymer obtained from any of the photoconductive phthalocyanine compounds and monomer mixtures (P-1) to (P-8) shown in Table 3 can be used. A printing original plate for electrophotolithography was prepared in the same manner as in Example 1 except that the polymer and additives were used and the heat treatment conditions and film thickness shown in Table 3 were used. The single-layer electrophotographic photoreceptor thus obtained as a printing original plate for electrophotographic engraving was negatively charged at -6, Qkv using a static zone tester. Thereafter, electrophotographic properties, alkali elution properties, and printing performance were evaluated in the same manner as in Example 1, and the results are shown in Table 4.

(Effects of the Invention) Since the printing original plate for electrophotographic engraving according to the present invention has the above configuration, it has the following effects.

(1) It has excellent electrophotographic properties and can perform electrophotographic engraving efficiently.

(2) It has excellent alkali elution properties and can perform effective etching in the plate-making process.

(3) A photosensitive layer with a low phthalocyanine content and a thin film thickness can be obtained while maintaining good electrophotographic properties (charging property, sensitivity).

(4) Since it exhibits good sensitivity even in a long wavelength region, it can be exposed using not only a normal light source such as a tungsten lamp but also a low-output laser. Therefore, direct plate making is possible using various light sources.

(5) The binder has a high affinity for zinc phthalocyanine and has good dispersibility.

(6) The printing plate obtained by electrophotographic engraving has excellent printing properties and can produce clear printed matter even after being used 100,000 times or more.

Also, Excellent storage stability It is.

Claims (1)

[Scope of Claims] (1) A printing original plate for electrophotographic engraving comprising a conductive support and a photosensitive layer made of an alkali-soluble binder containing an organic photoconductive compound; is the general formula I ▲ Numerical formulas, chemical formulas, tables, etc. ), and the binder is (a) at least one compound selected from the group consisting of hydroxyalkyl acrylates and hydroxyalkyl methacrylates; (b)
A monomer consisting of at least one copolymerizable unsaturated carboxylic acid, (c) at least one styrene compound, and (d) at least one compound selected from acrylic esters other than the hydroxyalkyl acrylate in (a). Electrophotography, which is a copolymer obtained by polymerizing a polymer mixture, and which is obtained by coating the photosensitive layer on a conductive support and then heat-treating it at a temperature in the range of 100 to 160°C. Original printing plate for plate making. (2) Claim 1 wherein the monomer mixture further contains at least one compound selected from methacrylic esters other than hydroxyalkyl methacrylate of (a).
The original printing plate for electrophotolithography described in . (3) The binder has (a) an alkyl group having 2 to 10 carbon atoms;
At least one selected from the group consisting of hydroxyalkyl acrylate and hydroxyalkyl methacrylate
0.5 to 40% by weight of a seed compound, (b) 10 to 40% by weight of at least one copolymerizable unsaturated carboxylic acid selected from the group consisting of acrylic acid, methacrylic acid and itaconic acid, (c) at least One type of styrene compound 10-7
0% by weight, (d) alkyl acrylate in which the alkyl group has 1 to 12 carbon atoms and cycloalkyl group has 5 to 12 carbon atoms;
5 to 50% by weight of at least one acrylic ester selected from the group consisting of cycloalkyl acrylates of No. 7; The number average molecular weight obtained by polymerizing a monomer mixture consisting of 0 to 40% by weight of at least one methacrylic ester selected from the group consisting of 5 to 7 cycloalkyl methacrylates is 1,000 to 50,000. The printing original plate for electrophotolithography according to claim 2, which is a copolymer of. (4) The printing original plate for electrophotolithography according to any one of claims 1 to 3, wherein the photosensitive layer that is used while being positively charged contains a sensitizer. (5) Electrophotography according to claim 4, wherein the sensitizer is at least one selected from the group consisting of compounds represented by the following general formulas III, IV, and V, succinic anhydride, and maleic anhydride. Original printing plate for plate making. ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(III) (In the formula, X^1 to X^5 may be the same or different, and each represents hydrogen, fluorine, -COOH or -NO_2. ), ▲Mathematical formulas, chemical formulas, tables, etc.▼...(IV) (In the formula, Y^1 to Y^4 may be the same or different, and each represents hydrogen, fluorine, -COOH or -NO_2) and ▲mathematical formulas, chemical formulas, tables, etc.▼...(V) (In the formula, Z^1 to Z^2 may be the same or different, and represent hydrogen, fluorine, -COOH or -NO_2). (6) In a photosensitive layer that is used while being charged with negative polarity, the photosensitive layer is made of an oxazole derivative, an oxadiazole derivative,
4. The printing original plate for electrophotolithography according to claim 1, which contains at least one charge transfer substance selected from pyrazoline derivatives, hydrazone derivatives, and triphenylamine derivatives. (7) The printing original plate for electrophotolithography according to claim 6, wherein the charge transfer substance is represented by the following general formula VI. ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(VI) (In the formula, R^1 and R^2 represent an aryl group or an aralkyl group, and R^3 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. group, benzyl group, alkoxy group having 1 to 4 carbon atoms, phenoxy group, or benzyloxy group.) (8) In a photosensitive layer that is used while being negatively charged, the photosensitive layer contains an aminotriazine resin. Items 1 to 3
The original printing plate for electrophotographic engraving according to any of the above. (9) The electronic device according to claim 8, wherein the aminotriazine resin is at least one selected from the group consisting of a benzoguanamine resin composition, a cyclohexylcarboguanamine resin composition, a melamine resin composition, and an acetoguanamine resin composition. Original printing plate for photoengraving. (10) The printing original plate for electrophotolithography according to claim 8, wherein the aminotriazine resin and the composition thereof are a condensate of methylolated aminotriazine, an alkyl ether, and a condensate of methylolated aminotriazine, respectively. (11) In a method for producing a printing original plate for electrophotolithography, which comprises providing a photosensitive layer made of an alkali-soluble binder containing an organic photoconductive compound on a conductive support, the organic photoconductive compound has the general formula I ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [However, in the formula, R represents a -SZ group (Z is a phenyl group, a phenyl group substituted with an alkyl group having 1 to 5 carbon atoms, or a naphthyl group) ], and the binder is (a) at least one compound selected from the group consisting of hydroxyalkyl acrylates and hydroxyalkyl methacrylates; (b)
A monomer consisting of at least one copolymerizable unsaturated carboxylic acid, (c) at least one styrene compound, and (d) at least one compound selected from acrylic esters other than the hydroxyalkyl acrylate in (a). A copolymer obtained by polymerizing a polymer mixture, and used for electrophotolithography, characterized in that the photosensitive layer is coated on a conductive support and then heat-treated in a temperature range of 100 to 160°C. A method for producing printing plates. (12) The printing original plate for electrophotolithography according to claim 11, wherein the monomer mixture further contains at least one compound selected from methacrylic acid esters other than the hydroxyalkyl methacrylate of (a). manufacturing method. (13) The binder has (a) an alkyl group having 2 to 1 carbon atoms;
0.5 to 40% by weight of at least one compound selected from the group consisting of 0 hydroxyalkyl acrylates and hydroxyalkyl methacrylates, (b) acrylic acid,
At least one copolymerizable unsaturated carboxylic acid selected from the group consisting of methacrylic acid and itaconic acid 10 to 40
% by weight, (c) at least one styrene compound 10~
70% by weight, (d) alkyl acrylate in which the alkyl group has 1 to 12 carbon atoms and cycloalkyl group has 5 carbon atoms;
5 to 50% by weight of at least one acrylic ester selected from the group consisting of ~7 cycloalkyl acrylates
and (e) an alkyl methacrylate in which the alkyl group has 1 to 12 carbon atoms and a cycloalkyl group has 5 to 7 carbon atoms.
0 to 40% by weight of at least one methacrylic ester selected from the group consisting of cycloalkyl methacrylates
Claim 1: A copolymer having a number average molecular weight of 1,000 to 50,000 obtained by polymerizing a monomer mixture consisting of
2. The method for producing a printing original plate for electrophotolithography according to 2. (14) forming a toner image on the printing original plate for electrophotographic engraving according to any one of claims 1 to 10 by electrophotography;
A lithographic printing plate obtained by etching away non-image areas with an alkaline etching solution after fixing.