JPH03129355A - Printing original plate for electrophotographic plate making and printing plate - Google Patents

Abstract

PURPOSE:To obtain the printing original plate for electrophotographic plate making having excellent electrophotographic characteristics and alkaline solubility by forming an org. photoconductive compd. of specific zinc phthalocyanine and a binder of a specific copolymer. CONSTITUTION:The org. phtoconductive compd. is formed of the zinc phthalocyanine expressed by formula I and the binder is formed of the copoly mer obtd. by polymerizing a monomer mixture consisting of a compd. selected from a group consisting of hydroxyl alkyl acrylate and hydroxyl alkyl methacrylate and a compd. selected from a copolymer unsatd. carboxylic acid, styrene compd. and the acrylate ester exclusive of the hydroxyl alkyl acrylate. In the formula I, R denotes a -SZ group (Z is a phenyl group, phenyl group or naphthyl group substd. with 1 to 5C alkyl group). The excellent electrophotographic characteristics and the excellent alkaline solubility are obtd. in this way and the execution of the effective etching in a plate making process is possible.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a printing original plate for electrophotographic engraving and a printing plate obtained by exposing and developing 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, and to a printing plate obtained by exposing and developing the same.

(Prior art) At present, due to technological advances in computer image processing and large-scale data communication, images are processed by computers, and the image information converted into digital signals is transmitted via telephone lines, communication satellites, etc. to the receiving side. A new system has been proposed, so-called electric printing, which prints by scanning exposure with a laser and is equipped with a scanner.

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 first written on a silver halide film, and then this film is exposed to deep blue light on the original printing plate for plate making, which requires large-scale equipment and takes time to make the plate. There are problems such as. Furthermore, many of the photosensitive dyes of the PS plate type utilize photochemical reactions and therefore require a large amount of exposure, and generally have low sensitivity. For this reason, the PS plate h type photosensitive dye 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 problems of the L PS plate system, a system using a silver halide photosensitive material r1 as a printing original plate for plate making and an h° system using an electrophotographic method have been proposed, and some of them have been put into practical use. Although the old method had good sensitivity, it had the drawbacks of poor printing durability and high cost per sheet.
are doing. On the other hand, the latter method allows direct plate making and has the potential to produce printing plates with relatively high sensitivity, low cost, and high printing durability.
It has been actively researched in recent years.

In printing original plates for electrophotographic engraving, zinc oxide, -ffi compounds, and the like are used as photoconductive substances. Printing plates for plate making using zinc oxide generally have (A) poor water resistance in the non-image area of the resulting printing plate, resulting in stains and (B)
Mechanical pressure applied during printing and penetration of dampening water cause the photosensitive layer to separate, resulting in poor printing durability. Although sensitization is carried out, it still does not have sufficient sensitivity in the long wavelength region of 600 nI11 or more, and has drawbacks such as difficulty in exposure with a semiconductor laser.

In the case of a printing original plate for plate making using a white photoconductive compound,
# After forming a photosensitive layer by providing a photosensitive H material in which a leading conductive compound is dispersed in a binder mainly composed of an alkali-soluble resin on a substrate such as a grained aluminum plate, the photosensitive layer is A toner image is formed on the 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 No. 54-134.632, Mukai No. 55-105,254, 1. =i155~153
．． In each publication of No. 948, a phenol resin is used as the alkali-soluble resin. However, when a phenolic resin is used as a binder for the fi JIR photoconductive compound, the formed film is fragile, and therefore there are drawbacks such as poor printing durability.

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 film formed is hard and may cause warping of the printing plate. It has drawbacks such as being prone to cracking.Acrylic resins are also widely used, and in JP-A No. 54-89,801, for example, water-based acrylic resin is used as a binder, and ε-type resin is used as an organic photoconductive compound. Although images can be formed using electrophotography, they have drawbacks such as not being easy to etch with aqueous alkaline solutions, and not being able to be exposed to light in the near-infrared region using semiconductor lasers, etc. .

In JP-A-56-146,145, an acrylic resin such as an acrylic acid/methyl methacrylate/butyl acrylate conjugate is used as an adhesive, A method using pigments based on pigments and oxadiazole derivatives is disclosed.These can be easily etched with an alkaline aqueous solution, but
The problem is that the electrophotographic properties are not fully satisfactory and the storage stability is poor. Furthermore, it also has drawbacks such as the inability to perform exposure in the near-infrared region using semiconductor lasers and the like. Furthermore, it is not possible to perform exposure in the near-infrared region using a semiconductor laser, or even if it is possible, the electrophotographic properties are insufficient, 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 (polymer, styrene/2-ethylhexyl acrylate/acrylic acid copolymer, methyl methacrylate/ethyl methacrylate/methyl A method has been disclosed in which an acrylic resin such as an acrylate/itaconic acid copolymer is used, and a pyrazoline derivative, zinc oxide, or α-type phthalocyanine is used as a lead conductor. It has drawbacks such as poor printing properties due to insufficient dissolution, low printing durability, and poor printing stability of printing plates.Also, it cannot be exposed to near-infrared light such as semiconductor lasers. Or, even if it were possible to do so, insufficient electrophotographic properties could be obtained, resulting in problems such as 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 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 engraving and a printing plate for lithographic printing using an organic photoconductive compound. Still another object of the present invention is to provide a printing plate for electrophotographic engraving which is excellent in electrophotographic properties and alkali elution property, and a printing plate for lithographic printing which has excellent printing properties.

Another advantage of the present invention is that it has good storage stability and printing durability.
An object of the present invention is to provide a printing original plate for electrophotolithography which provides a printing plate with a high quality. Still another object of the present invention is to provide a printing original plate for electrophotolithography in which a photosensitive layer with excellent light resistance and weather resistance is formed by using a stone agent that has good adhesion to a substrate and good mechanical strength. It's about doing. Another object of the invention is to
The 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.

(Means for Solving the Problems) These various aspects are applicable to printing original plates for electrophotolithography, which are provided with a photosensitive layer made of an alkali-soluble binder containing a six-layer conductive compound on a conductive support. , the organic photoconductive compound has the general formula I [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) An electrophotographic copolymer obtained by polymerizing a monomer mixture consisting of at least one compound selected from acrylic esters other than hydroxyalkyl acrylate in (a). This is accomplished by a printing master.

These terms can also be used with a printing plate for lithographic printing obtained by forming a toner image on a former i2 printing plate for electrophotographic printing by electrophotography, and after fixing, removing the non-image area by etching with an alkaline etching liquid. achieved.

(Function) The printing original plate for electrophotographic engraving according to the present invention has a photosensitive layer formed on a conductive support, and the photosensitive layer is made of an alkali-soluble adhesive containing an organic photoconductive compound. It is what it is.

The electroconductive 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 general 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) 52 10 7 .
A total of 8 items were introduced in 12.13 and 6th place. Note that the names in [ ] are abbreviations.

Octafluoro-octakis (phenylthio) zinc phthalocyanine [Fs (PhS) a ZnPc] octafluoro-octakis (o-tolylthio) zinc phthalocyanine [FB (o-MePhS) B ZnPc] octafluoro-octakis (m-h lylthio) Zinc phthalocyanine [FB (m-MePhS)B ZnPc] octafluoro-octakis (p-tolylthio) zinc phthalocyanine [Fa (p-MePhS) a ZnPc] octafluoro-octakis (2,4-xylylthio) zinc phthalocyanine [Fa (2 ,4-MePhS)a ZnPc1 octafluoro-octakis(2,3-xylylthio)zinc phthalocyanine [Fa (2,3-MePhS)a ZnPc1 octafluoro-octakis(0-ethylphenylthio)zinc phthalocyanine [FB (0-EtPhS) )B ZnPc1 octafluoro-octakis(p-ethylphenylthio) zinc phthalocyanine [Fa (p-EtPhS)a ZnPc1 octafluoro-octakis(0-isopropylphenylthio)
Zinc phthalocyanine [Fa (o-IPrPhS) a ZnPc] octafluoro-octakis (p-isopropylphenylthio) zinc phthalocyanine CF'8 (p-IPrPhS) a ZnPc] octafluoro-octakis (0-butylphenylthio) Aibutsu phthalocyanine [FB (o-BuPhS)B ZnPc1 Octafluoro-octakis (m-butylphenylthio) zinc phthalocyanine [FB (m-BuPh,S)B ZnPc1 Octafluoro-octakis (p-butylphenylthio) zinc phthalocyanine [FB (p -BuPhS)B ZnPcE octafluoro-octakis(p-tertiarybutylphenylthio)zinc phthalocyanine [Fs (pt-Bu
PhS) B ZnPc] octafluoro-octakis (
Naphthylthio) zinc phthalocyanine [Fa (NPhS)a ZnPc] - Zinc phthalocyanine represented by the formula (■) is 3.4.
5.6-Chitrafluorophthaloni!・It can be produced as follows using Lil as a starting material.

3. R8HSR of 4,5,6-titrafluorophthalonitrile in a single solvent such as methanol or acetonitrile in the presence of a condensing agent such as an alkaline substance (e.g. KF)
5Na or R8K (here, R represents a phenyl group or a naphthyl group) to form 3,4,5.6
- Synthesize titrafluorophthalonitrile in which the fluorine atoms at the 4th and 5th positions are substituted with a functional group, and then combine the obtained phthalonitrile with a pe-substituted group with zinc powder or zinc halide. The zinc phthalocyanine is obtained by heating and melting or by heating in a zero solvent.

The binder used in the present invention includes (a) at least one compound selected from the group consisting of hydroxyalkyl acrylate and hydroxyalkyl methacrylate; a commercially 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 esters other than hydroxyalkyl methacrylate (a).

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

The use of monomer (a) improves electrophotographic properties and durability as a printing plate. Moreover, a uniform and clean coating film can be obtained. By introducing a hydroxy group into the binder, the adhesiveness of the binder to the conductive support and the affinity with the phthalocyanine of the present invention are improved, thereby improving the dispersibility. This is considered to be the result. It also has the effect of improving alkali etching properties, and can also reduce metaplasia of copolymerizable unsaturated carboxylic acids, which deteriorates electrophotographic properties when metaplasia 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. This usage rate is 0. Less than 5% by weight or 40fTi'f
If it exceeds #%, the electrophotographic properties and durability of the printing plate will deteriorate, which is not preferable.

Monomer (b) is at least one persimmon co-comiccial 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 usage rate of single m body (b) is
It is 10 to 40 iT [9to, preferably 15 to 30% by weight of the total vehicle 61 temperature mixture. If the usage ratio is less than 10% by weight, the alkali solubility of the monomer becomes low and the etching rate decreases. On the other hand, if it exceeds 40% by weight, the banding property decreases and the photosensitive layer It can no longer be used as a

In the copolymer used as a binder in the present invention, carboxylic acid (
Introduced during coalescence to increase the acid value from 50 to 3001ig-KOI
Adjust to I/g range. In other words, like this” (
By using a specific proportion of m-component carboxylic acid,
Etching properties can be improved without impairing electrophotographic properties.

The 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 single-stage body (c) used is 10 to 70% of the solid mixture of the entire vehicle.
Ichibin%, preferably 25 to 51ff1%. If the usage ratio is less than 10%, the strength, affinity with phthalocyanine (dispersibility), and bandability will decrease. On the other hand, when it exceeds 70 weight%, monomers (a) and (b) are relatively
) decreases, which is undesirable because the effects described above due to the use of monomers (a) and (b) are lost.

Monomer (d) is a compound of at least lfi selected from acrylic esters other than hydroxyalkyl acrylate as monomer (a).

Specifically, this 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. be.

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 cyclohebutyl 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 this proportion is within the range specified above, the lipophilicity can be improved by 6e, the binding strength of the resulting copolymer is strengthened, and the retreadability is improved, but if it exceeds 50i%,
Since the proportion of monomers (a), (b) and (c) is relatively reduced, the above-mentioned effects due to the use of monomers (a), (b) and (c) are lost, which is not preferable. . In the present invention, the single stage body (e) used as necessary is at least one compound selected from methacrylic acid esters other than hydroxyalkyl methacrylate as a single stage body. Specifically, the methacrylate 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 group has 5 carbon atoms.
~7 cycloalkyl methacrylate.

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 cyclohexyl methacrylate. The proportion of alkyl methacrylate or cycloalkyl methacrylate used is 0 to 4C1fTi:ff1%, preferably 15' of the whole car body mixture.
TCGt% or less. If this usage ratio is within the above range, durability can be improved, and if it exceeds 40iT (ff1%), the dispersibility with phthalocyanine will deteriorate, which is not preferable.

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

(p-1) 2-hydroxypropyl acrylate/acrylic acid/styrene/butyl acrylate (5/20/35
/40 (weight ratio, hereinafter 1ol)), (p-2) 2-hydroquinethyl methacrylate/methacrylic acid/styrene/butyl acrylate (2/23/40/35), (p-3) 2-hydroxybutyl methacrylate/acrylic acid/styrene/isopropyl acrylate (15/2
5/45/15), (p-4) 3-hydroxypropyl methacrylate/acrylic acid/styrene/methyl acrylate/ethyl methacrylate (5/20/35/25/15), (p-5) Acrylic 3-hydroxybutyl acid/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/itacon Acid/styrene/butyl acrylate/methyl methacrylate (10/15/35/30/10), (p-8) 3-hydroxybutyl 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-mentioned finger mixture, and examples include bulk polymerization, solution polymerization, or suspension polymerization in the presence of a radical initiator such as peroxides, hydroperoxides, or azobisisobutyronitrile. 50 to 100°C, preferably 70 to 90°C, by the usual polymerization method such as
It can be carried out at a temperature of °C. 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 to 30,000.

A polymer obtained by polymerizing the above monomer mixture, especially Affi having a number average molecular weight within the range specified in 1.
The copolymer is soluble in an alkaline substance, and the photosensitive layer obtained by coating this copolymer together with the lead conductive phthalocyanine compound exhibits long alkali solubility and has excellent etching properties.

The printing original plate for electrophotographic engraving of the present invention is prepared by coating a conductive support with a coating liquid comprising the above-mentioned conductive phthalocyanine compound and a polymer as an adhesive to form a photosensitive layer. It is something.

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 electroconductive phthalocyanine compound in separate solvents, and then mixing the two. 1. Solvents used for dissolving or dispersing the adhesive and the leading conductive phthalocyanine compound include aromatic hydrocarbons such as benzene and toluene, cyclic ethers such as tetrahydrofuran and dioxane, and halogens such as chloroform, dichloromethane and dichloroethane. V′r organic solvents such as n-containing hydrocarbons, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate, and cellosolves such as methyl cellosolve can be used.

When preparing the above-mentioned coating liquid, the photoconductive phthalocyanine compound is preferably used in a proportion of 3 to 50% by weight, preferably 5 to 30% by weight of the adhesive.

In addition, the concentration of the photoconductive phthalocyanine compound and the adhesive dissolved or dispersed in the solvent is usually 0.5 to 5.
It is 0 weight percent, preferably 5 to 30 weight percent.

The decyclization of the photosensitive layer is carried out at 2-10 μm, especially 3-6 μm force <l
It's so sad. This is unwise as the unseating becomes abrasive and side edges tend to come out during pigeonhole etching, making it easier to scrape off fine lines. If the dislocation becomes thinner, the charging property deteriorates, which is not preferable.

1-. The coating solution for forming the photosensitive layer contains polybasic acid-6-organic compounds, such as those represented by the following general formulas (1), (2), and (2), in the photosensitive layer that is used after being charged with positive polarity. The electrophotographic properties can be further improved by containing a compound selected from succinic anhydride and maleic anhydride as a sensitizer.

(In the formula, X1 to X5 may be the same or different, and each is hydrogen, fluorine, -COOH or -
(represents NO2).

(In the formula, Y1 to Y4 may be the same or different, and each is hydrogen, fluorine, -COOH or -
(represents NO2).

(In the formula, 21 to Z2 may be the same or different, and each represents 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.

L 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, in the coating liquid for forming the photosensitive layer described in ``2'', in the photosensitive layer used after being charged with negative polarity, oxazole derivatives, oxadiazole derivatives, pyrazoline derivatives,
The properties of the electrophotographic photoreceptor can be further improved by incorporating a charge transfer substance such as a hydrazone derivative or a triphenylamine derivative 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, R+ 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. ) The following are specific examples of the hydrazine compounds represented by the above-mentioned formulas.

(c1'-1) (cT-2) (cT-3) (cT-4) (c1''-5) (cT-6) (cT-7) (cT-9) (cT-If) (cI'' -12) (cT-13) "Aminotriazine resins include, for example, melamine resin, benzoguanamine resin, acetoguanamine resin, CT
Examples include U 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.
Alkyl ether methylolated products can be used as they are or after dehydration and condensation of each of them to an appropriate degree. The weight transfer material and/or the aminotriazine resin are preferably used in a proportion of up to 60% by weight of the photoconductive phthalocyanine compound, particularly in a proportion of 0.1 to 20% by weight.

The conductive support used in the present invention does not have any specific features, such as commonly used aluminum plates, zinc plates,
Or copper - aluminum plate, copper stainless steel plate, chrome -
A material having a white hydrophilic surface can be used, such as a bimetallic plate such as a copper plate or a trimetallic plate such as a chromium-copper-aluminum plate, a chromium-copper-iron plate, or a chromium-copper-stainless steel plate. The thickness of the conductive support is 0.05
A degree of opening of ~0.5 is preferred.

In particular, in the case of a support with an aluminum surface treated with hydrogen, it is preferable to use a support that has undergone surface treatment such as graining treatment, immersion treatment in an aqueous solution such as sodium silicate or potassium fluorozirconate, or anodization treatment. .

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. In addition, in the present invention, for the purpose of increasing printing durability, between the conductive support base H 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, in accordance with the usual electrophotographic method, the image is first 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 at step 7 or by scanning exposure using a laser tip such as a He-Ne laser, argon radar, or semiconductor laser, and this electrostatic latent image is applied with toner. It is developed and heated to obtain a toner image on the photosensitive layer.

The toner must be hydrophobic, ink receptive, and have sufficient adhesion to the original printing plate to withstand printing, and must also have resistivity when etched with an alkaline aqueous etching solution. . Furthermore, as an electrophotographic developer, it is best to use a liquid developer, which has better resolution than a powder developer. To meet these conditions, toners containing styrene resin, acrylic resin, styrene-acrylic resin, styrene-methacrylic resin, polyester resin, epoxy resin, etc. are used as the resin in the liquid developer. It is better. 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, so that toners with positive charge ff or negative charge h' can be created depending on the purpose. It is better to use it.

Next, when the plate-making printing plate No. 1 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.
The aqueous surface of the conductive body 144 is exposed, and only the image area of the toner image remains on the support surface, making it possible to obtain the intended printing plate for lithographic printing.

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

EDTA-414g 30% benzyl alcohol, 5g monoethanolamine, and dilute the total amount to 11% with water.
f! 60 g of triethanolamine 25 g of NaOH (combined) The printing original plate for electrophotographic engraving can also be used as an electrophotographic photoreceptor for a laser blender (OPC). In a laser printer, the developed toner is transferred to paper and fixed on the paper.

(Examples) Hereinafter, the present invention will be explained in more detail with reference to Production Examples and Examples. Note that "parts" and "%" mean "parts by weight" and "!I2% by weight" unless otherwise specified.

Production Example 1 [Production of Fs (PhS)s ZnPc] (1) Synthesis of starting seasoning 3.4,5.6-te!・
Rafluorophthalonitrile i9. 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 at 50° C. for 12 hours under stirring of 1 g.

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 warm water to obtain 3,6-difluoro-4°5-bisphenylthiophthalonitrile 34 .5g (vs. 3.4.5.6-
Titrafluorophthalonitrile yield, g2.5 mol%)
I got it.

(2) Synthesis of Fa (Phi)a ZnPe] 00m
10 g (26.2 mmol) of 3,6-difluoro-4,5-bisphenylthiophthalonitrile, 3.14 g (9.8 mmol) of iodide, and 50 ml of benzonitrile were placed in a 4-tubular flask of 1. A stacking reaction was carried out at ℃ for 6 hours. Thereafter, it was cooled and the resulting green solid was filtered and then washed using a Soxhlet with methanol, benzene, and acetone in that order.
hS)s ZnPc (vs. 3,6-difluoro-4,5
~9.4 mol % of bisphenylthiophthalonitrile) was obtained.

Production Example 2 [Production of copolymer] (The polymer can be produced, for example, as follows. Stirrer, temperature = 1°, cooling pipe, nitrogen introduction pipe, monomer mixture dropping funnel) and isopropanol 40 as a solvent in a separable flask equipped with a polymerization initiator dropping funnel.
After adding the flask, nitrogen is introduced 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, and 0.2 parts of azobisisobutyronitrile was charged into the polymerization initiator dropping funnel. While adjusting the flask internal temperature to 80°C, monomer mixture 1 and polymerization initiator were added dropwise over 2 hours, then at 80°C for 2 hours, then at 85-90°C.
After applying the adhesive for 2 hours, it is cooled.

Example I 1.5 parts of FB (o-MePhS)B ZnPc,
0.05 part 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 0.1.5 m.
It was placed on an aluminum plate that had been grained and anodized, and heated with hot air at 60°C for 30 minutes, and then heated under reduced pressure (1 m
mmm1l was dried at 100° C. for 2 hours to form a photosensitive layer. The film (photosensitive layer) thickness 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, it was held in a dark place for 5 seconds, and then exposed to white light (tungsten lamp) at an illumination intensity of 5 lux for 5 seconds, and the charging characteristics (surface potential (Vo), potential after being held in a dark place for 5 seconds (V5) ), the potential before exposure is reduced by 1/
Exposure ff required to attenuate to 2 (E172) (
(Lux-scc)) and 780 nm monochromatic light separated by a spectral filter at 0.5 parts w/c♂ to determine the half-reduction exposure energy sensitivity (μJ/Cr1).

Next, this single layer type electrophotographic photoreceptor was coated with 0. The photosensitive layer was removed by immersing it in an aqueous solution containing 5% sodium hydroxide and washing with water. 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 this grained aluminum plate prepared separately was made into a plate by a liquid development method using a Toppan Printing TTP laser plate making machine (manufactured by Toppan Printing Co., Ltd. fJ). did. 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 1.

The printing plate thus prepared was printed using an offset printing method in a conventional manner, and the degree of background smearing and the clarity of printing were evaluated after incision and after printing 100,000 sheets.

Table 2 shows the results of the evaluation of electrophotographic properties, alkali elution properties, 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 1-kunji photoengraving was prepared in the same manner as in Example 1 except that the polymer and sensitizer were used, and its electrophotographic properties, alkali elution property, and printing performance were evaluated, and the results are shown in Table 2. It was shown to. In addition, the electrophotographic photoreceptor prepared above was left in a room with fluorescent lights on for two months.
After measuring the electrophotographic characteristics and printing performance, 2
Even after the power month, there was almost no difference in performance.

Comparative Examples 1 to 6 In Example 1, FB (o-MePhs)sZn
J of Pc and the monomer mixture (P-1) (instead of the polymer, the leading conductive phthalocyanine compound shown in Table 1, (P
-1) to (P to 8) or a copolymer and sensitizer obtained from the following monomer mixtures of (S-1) to (S-5) produced in the same manner as Production Example 2. The electrophotographic properties, alkali elution properties, and printing performance were evaluated in the same manner as in Example 1, except that the results are shown in Table 2.

(S-1) (S-2) (S-3) (S-4) Acrylic acid/Butyl acrylate/ Butyl methacrylate (25/20/55), Methacrylic acid/Styrene/ Isopropyl acrylate (30/15155), Methacrylic acid/Methyl acrylate/ ethyl methacrylate (15/60/25), Acrylic acid/Styrene/ Ethyl acrylate/ Methyl methacrylate (25/8/20/47), (S-5) Acrylic acid/Butyl acrylate/ Methyl methacrylate/ 2-hydroxyethyl methacrylate (10/40/40/10').

Examples 18-27 In Example 1, FB (o MePhS)sZ
Instead of the copolymer of nPc 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. The single-layer electrophotographic photoreceptor thus obtained as a printing plate for electrophotographic engraving was charged to -6.0 kV using a static test device. 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 following configuration, it has the following effects.

(1) It has excellent electrophotographic properties and can perform electrophotographic engraving with good speed.

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

(3) A thin photosensitive layer of the film 4 with a low phthalocyanine content and good electrophotographic properties (charging property, sensitivity) can be obtained.

(4) Since it exhibits reasonable sensitivity even in the long wavelength region, it can be exposed not only with ordinary light sources such as tungsten lamps but also with low-power lasers. Therefore, direct plate making is possible using occasional light sources.

(5) The binder has a high affinity for normal lead 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 more than 100,000 times.

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. 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). 1. A printing original plate for electrophotographic engraving, characterized in that it is a copolymer obtained by polymerizing a polymer mixture. (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) forming a toner image on the printing original plate for electrophotographic engraving according to any one of claims 1 to 10 by electrophotography;
A printing plate for lithographic printing obtained by etching away non-image areas with an alkaline etching solution after fixing.