JPH1124275A - Manufacture of photosensitive lithographic printing plate and photosensitive lithographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the photosensitive the lithographic printing plate improved in image defects due to depiction with a ballpoint pen on the surface of a photosensitive layer and good in developability and resistances to printing and chemicals and to provide its manufacturing method (especially, capable of obtaining the above merits even in the case of thinning the photosensitive layer). SOLUTION: The photosensitive lithographic printing plate is provided with plural cost layers including the photosensitive layer containing a compound to be allowed to release an acid or radicals by irradiation with light, acive radiation, or electron beams on a support, and its uppermost layer of the above- mentioned coat layers contains a filler smaller in the average particle diameter than the thickness of this layer and its dried layer thickness is <=0.5 μm, and this layer and at least one of the coat layers are formed by a wet-on-wet coating system. The uppermost layer of thin photosensitive lithographic printing plate has the average surface roughness (Ra) and the 10 point average roughness (Rz), and the maximum surface roughness (Rmax) satisfying the following expressions: Rz/Ra<=8, and Rmax/Ra<=14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive lithographic printing plate and a method for producing a photosensitive lithographic printing plate, and more particularly, to a reduction in printing durability and chemical resistance caused by thinning, a registration and a mark. Therefore, the present invention relates to improvement of a problem that a mark formed by marking with a ballpoint pen on the surface of a photosensitive layer remains on a lithographic printing plate after plate making and hinders.

[0002]

2. Description of the Related Art A lithographic printing plate is a printing system that skillfully utilizes the property that water and oil are not essentially mixed. When a positive photosensitive lithographic printing plate is subjected to image exposure on the photosensitive layer and then developed, the photosensitive layer which is ink-receptive in the exposed areas is removed and the surface of the hydrophilic support is exposed, while the unexposed areas are exposed. The photosensitive layer that is ink receptive remains on the support to form ink receptivity.

It is effective to reduce the thickness of the photosensitive layer in order to reduce the amount of waste liquid and to speed up the processing, but there is a problem in that thinning reduces the printing durability and chemical resistance. In addition, during a plate making operation for preparing a lithographic printing plate using a photosensitive lithographic printing plate, a mark may be formed on the photosensitive layer of the photosensitive lithographic printing plate with a ball-point pen for registration or marking. The marked portion is naturally developed when exposed, and the surface of the hydrophilic support must be exposed, but the ballpoint pen ink may remain on the support surface (hereinafter referred to as “ballpoint pen residue”). Conversely, the surface of the hydrophilic support may be exposed similarly to the exposed portion even though the portion marked with the ballpoint pen is an unexposed portion (hereinafter referred to as "ballpoint pen jarre").

In order to solve these problems, the present inventors have dealt with a method of improving the developability of the photosensitive layer. However, if the developability of the photosensitive layer is to be improved, printing durability, gradation property, etc. There is a problem that the opposite phenomenon occurs when trying to increase the printing durability. Therefore, it is very difficult to improve the ball-point pen residue and the ball-point pen-unevenness and to have good developability, printing durability and chemical resistance, especially when the photosensitive layer becomes thin.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a positive photosensitive lithographic printing plate having improved ballpoint pen residue and ballpoint pen lurre, good developability, printing durability and chemical resistance, and a method for producing the same. In particular, it is an object of the present invention to provide a photosensitive lithographic printing plate capable of obtaining the above-described effects when the photosensitive layer is thinned for the purpose of reducing the processing waste liquid and speeding up the processing, and a method of manufacturing the same. And

[0006]

The present invention to achieve the above object is as follows.

(1) A method for producing a photosensitive lithographic printing plate comprising providing, on a support, two or more coating layers including a photosensitive layer containing a compound capable of generating an acid or a radical by light, actinic radiation or electron beam. Wherein the uppermost layer of the coating layers contains a filler having an average particle size smaller than the dry thickness of the uppermost layer, the dry thickness of the uppermost layer is 0.5 μm or less, and the uppermost layer and A method for producing a photosensitive lithographic printing plate, comprising applying at least one of the coating layers other than the uppermost layer by a wet-on-wet method.

(2) A photosensitive lithographic printing plate comprising a support having at least two layers including a photosensitive layer containing a compound capable of generating an acid or a radical by light, actinic radiation or electron beam. The average surface roughness (Ra), the 10-point average roughness (Rz), and the maximum surface roughness (Rmax) of the uppermost layer among the two or more layers satisfy the following conditions (a) and (b). A photosensitive lithographic printing plate characterized by the following.

(A) Rz / Ra ≦ 8 (b) Rmax / Ra ≦ 14 Hereinafter, the present invention will be described in detail.

The support for the photosensitive lithographic printing plate according to the first or second aspect of the invention may be any support that is used as a support for a photosensitive lithographic printing plate. For example, paper, plastic (eg, polyethylene, polypropylene, polystyrene, etc.) laminated paper, metal plates such as aluminum (including aluminum alloys), zinc, copper, etc., cellulose diacetate, cellulose triacetate, cellulose propionate, polyethylene Plastic films such as terephthalate, polyethylene, polypropylene, polycarbonate, polyvinyl acetal, etc .; paper or plastic films on which the metal is laminated or vapor-deposited; aluminum or chrome-plated steel sheets; and the like. Particularly preferred are aluminum and aluminum-coated composite supports.

The surface of the aluminum material enhances water retention,
It is desirable that the surface has been roughened for the purpose of improving the adhesion to the photosensitive layer.

Examples of the surface roughening method include known brush polishing methods, ball polishing methods, electrolytic etching, chemical etching, liquid honing, sand blasting and the like, and combinations thereof, and preferably brush polishing methods, electrolytic etching. , Chemical etching and liquid honing, of which a surface roughening method including the use of electrolytic etching is particularly preferred. As the electrolytic bath used in the electrolytic etching, an aqueous solution containing an acid, an alkali or a salt thereof or an aqueous solution containing an organic solvent is used, and among these, an electrolytic solution containing hydrochloric acid, nitric acid or a salt thereof is particularly used. Liquids are preferred. Further, the roughened aluminum plate is desmutted with an acid or alkali aqueous solution as required. The aluminum plate thus obtained is desirably subjected to anodic oxidation treatment, and particularly preferably a method of treating with a bath containing sulfuric acid or phosphoric acid. Further, if necessary, surface treatment such as treatment with alkali silicate or hot water, or immersion in a water-soluble polymer compound or an aqueous solution of potassium fluorozirconate can be performed.

In the invention according to claim 1 or 2, the photosensitive layer coated on the support generates an acid or a radical by light, actinic radiation or electron beam used as a photosensitive layer of a photosensitive lithographic printing plate. And a layer of a photosensitive composition containing the compound. Examples of the photosensitive composition include a positive photosensitive composition containing an o-quinonediazide compound as a photosensitive component, a negative photosensitive composition containing a photosensitive diazonium salt or a photosensitive azide compound as a photosensitive component, and addition polymerization. Radical photopolymerizable photosensitive composition containing a compound having a possible ethylenically unsaturated double bond as the main component, and negative photosensitive composition containing a photocrosslinkable compound containing a cinnamic acid or dimethylmaleimide group as a photosensitive component A composition is included.

The o-quinonediazide compound used in the positive photosensitive composition containing the o-quinonediazide compound as a photosensitive component includes, for example, o-naphthoquinonediazidesulfonic acid, and a polycondensation resin of phenols and aldehydes or ketones. Ester compounds of the formula (I).

Examples of the above phenols include monohydric phenols such as phenol, o-cresol, m-cresol, p-cresol, 3,5-xylenol, carvacrol, thymol, and divalent such as catechol, resorcin, and hydroquinone. Examples include trihydric phenols such as phenol, pyrogallol, and phloroglucin.

Examples of the aldehyde include formaldehyde, benzaldehyde, acetaldehyde, crotonaldehyde, furfural and the like. Preferred among these are formaldehyde and benzaldehyde. Examples of the ketone include acetone and methyl ethyl ketone.

Specific examples of the polycondensation resin include phenol / formaldehyde resin, m-cresol / formaldehyde resin, m- and p-mixed cresol / formaldehyde resin, resorcinol / benzaldehyde resin, pyrogallol / acetone resin and the like. Can be

The photosensitive layer containing an orthoquinonediazide compound as a photosensitive material preferably contains an alkali-soluble resin. As the alkali-soluble resin,
Examples include a novolak resin, a vinyl polymer having a phenolic hydroxyl group, and a condensation resin of a polyhydric phenol and an aldehyde or ketone described in JP-A-55-57841.

The proportion of the o-quinonediazide compound in the photosensitive layer is preferably from 6 to 60% by weight, particularly preferably from 10 to 50% by weight.

The photosensitive layer containing the o-quinonediazide compound as a photosensitive material may optionally contain a plasticizer, a surfactant, an organic acid, an acid anhydride and the like. Furthermore, in order to improve the oil sensitivity of the photosensitive layer, for example, p-tert-butylphenol formaldehyde resin or pn-octylphenol formaldehyde resin, or these resins are partially esterified with an o-quinonediazide compound. A sensitizing agent such as a resin may be added.

In a photosensitive composition containing an o-quinonediazide compound as a photosensitive component or a photosensitive composition containing a photopolymerizable or photocrosslinkable photosensitive component, a printout material that forms a visible image upon exposure is provided. Can be added. The printout material is used with a compound that produces an acid or free radical upon exposure to light and changes its color by interacting with the acid or free radical generated from the compound upon exposure to form a color image.

Various additives can be further added to a photosensitive layer comprising a photosensitive composition containing an o-quinonediazide compound or a photopolymerizable or photocrosslinkable photosensitive component. For example, alkyl ethers for improving coatability (for example, ethyl cellulose, methyl cellulose),
Fluorosurfactants, nonionic surfactants (for example,
Pluronic L-64 (manufactured by Asahi Denka Co., Ltd.)], a plasticizer (for example, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate) for imparting flexibility and abrasion resistance to the coating film. Dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, oligomers and polymers of acrylic acid or methacrylic acid), and oil-sensitization for improving the oil-sensitivity of the image area Agents (for example, a half-esterified product of a styrene-maleic anhydride copolymer with an alcohol described in JP-A-55-527), a stabilizer [for example,
Phosphoric acid, phosphorous acid, organic acids (citric acid, oxalic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5-sulfonic acid, tartaric acid, etc.)), development accelerators (for example, Fine alcohol,
Acid anhydride). The amount of these additives varies depending on the purpose of use, but is generally 0.01 to 30% by weight based on the total solid content of the photosensitive composition.

The photosensitive diazonium salt is, for example, preferably a diazo resin represented by a condensate of an aromatic diazonium salt with formaldehyde or acetaldehyde. Particularly preferably, a salt of a condensate of p-diazophenylamine with formaldehyde or acetaldehyde,
For example, a diazo resin inorganic salt which is a reaction product of hexafluoroborate, tetrafluoroborate, perchlorate or periodate with the condensate, and US Pat.
Examples thereof include organic salts of diazo resins, which are reaction products of the above condensates and sulfonic acids, as described in JP-A-00,309. Furthermore, diazo resins are preferably used with binders. As such a binder, various polymer compounds can be used. Preferably, a monomer having an aromatic hydroxyl group, for example, N-type monomer described in JP-A-54-98613 is used. (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide, o-, m-, or p-
Copolymers of hydroxystyrene, o-, m-, or p-hydroxyphenyl methacrylate and the like with other monomers,
Polymers containing hydroxyethyl acrylate units or hydroxyethyl methacrylate units as main repeating units, natural resins such as shellac and rosin, polyvinyl alcohol, as described in U.S. Pat. No. 4,123,276; Patent No. 3,751,257, linear polyurethane resin, phthalated resin of polyvinyl alcohol, epoxy resin condensed from bisphenol A and epichlordrine, cellulose acetate, cellulose acetate phthalate, etc. Are included.

As the photopolymerizable photosensitive composition, any of the known photopolymerizable photosensitive compositions can be applied to the present invention. For example, a vinyl monomer having at least two terminal vinyl groups can be used. A photosensitive composition containing a monomer, a photopolymerization initiator, and a polymer compound as a binder as main components can be used.

Examples of the vinyl monomer include, for example, JP-B-35-5093, JP-B-35-14719, and JP-B-44-719.
No. 28727 are used, and acrylic acid or methacrylic acid esters of polyols [for example, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylol Propanetri (meth) acrylate], methylenebis (meth) acrylamide, bis (meth) acrylamides such as ethylenebis (meth) acrylamide, and unsaturated monomers containing a urethane group such as di-
Reaction products of diol mono (meth) acrylates and diisocyanates such as (2'-methacryloxyethyl) -2,4-tolylene diurethane, di- (2-acryloxyethyl) trimethylene diurethane and the like. Can be

Examples of the photopolymerization initiator include those described in J.
"Light Sensitive Systems" by Kosar
Examples include carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo and diazo compounds, halogen compounds, photoreducing dyes and the like as described in Chapter 5. A specific photopolymerization initiator is disclosed in British Patent No. 1,459,563, and the photopolymerization initiator disclosed in the specification is used in the photosensitive layer of the photosensitive lithographic printing plate of the present invention. Can be applied.

Examples of the polymer compound to be contained as the binder include polyester resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, vinyl chloride resin, polyamide resin, polyvinyl butyral resin, epoxy resin, and acrylate copolymer. , Vinyl acetate copolymers, phenoxy resins, polyurethane resins, polycarbonate resins, polyacrylonitrile butadiene, polyvinyl acetate, lipophilic polymer compounds having a hydroxyl group (for example, monomers having an aliphatic hydroxyl group in a side chain, for example,
A copolymer of 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate with another copolymerizable monomer), a monomer having an aromatic hydroxyl group (for example, N- (4-hydroxyphenyl) acrylamide,
N- (4-hydroxyphenyl) methacrylamide, o
-, M- or p-hydroxystyrene, o-, m- or p-hydroxyphenyl methacrylate) and another copolymerizable monomer, a repeating unit mainly comprising a hydroxyethyl acrylate unit or a hydroxyethyl methacrylate unit Including polymers, shellac,
Natural resin such as rosin, polyvinyl alcohol, polyamide resin, linear polyurethane resin, phthalated resin of polyvinyl alcohol, epoxy resin obtained by condensing bisphenol A and epichlorohydrin, alkali-soluble resin (for example, novolak resin, vinyl resin having phenolic hydroxyl group) Polymer, condensation resin of polyhydric phenol and aldehyde or ketone) and the like. As the novolak resin, for example, phenol / formaldehyde resin, cresol / formaldehyde resin, phenol / formaldehyde resin
A cresol-formaldehyde copolycondensation resin, a p-substituted phenol and phenol, or a cresol and formaldehyde copolycondensation resin may, for example, be mentioned.

These photopolymerizable photosensitive compositions can contain known additives such as diazo compounds, thermal polymerization inhibitors, plasticizers, dyes and pigments.

As the photo-crosslinkable photosensitive material, for example,
A photosensitive material containing a compound having a photodimerizable group can be used. As the above compound, for example, cinnamate, β-furyl acrylate, α-
Cyanocinnamate, p-azido cinnamate, β-styryl acrylate, α-cyano-β
-Styryl acrylate, p-phenylenediacrylate, p- (2-benzoylvinyl) -cinnamate, β-naphthyl acrylate, cinnamylidenpyruvate, α-methyl-β-styryl acrylate Acid ester, α-phenyl-β-styryl acrylate, α-cyano-β-furyl acrylate, p-dimethylaminocinnamate, and amides, chalcone, benzylideneacetone, stilbazole corresponding to the above esters , Stilbene, α-
Examples include phenylmaleimide, coumarin, pyrone, anthracene, dibenzazepine, and derivatives thereof.

A sensitizer can be used in combination with the photocrosslinkable photosensitive compound. As typical examples of the sensitizer, 2,
4,7-trinitro-9-fluorenone, 5-nitroacenaphthene, p-nitrodiphenyl, p-nitroaniline, 2-nitrofluorenone, 1-nitropyrene, N-
Acetyl-4-nitro-1-naphthylamine, N-benzoyl-4-nitro-1-naphthylamine, Michler's ketone, N-butylacridone, 5-benzoylacenaphthene, 1,8-phthaloylnaphthalene, 1,2- Benzanthracene, 9,10-phenanthraquinone, chlorbenzanthrone, N-phenylthioacridone,
1,2-benzanthraquinone, N-methyl-2-benzoylmethylene-β-naphthothiazole, 2-chlorothioxatone, 2,4-dimethylthioxanthone, 2,4
-Diisopropylthioxanthone, eosin, eristosin, picramide and the like.

The photosensitive layer using a photocrosslinkable photosensitive compound may contain an inorganic powder or a polymer, if necessary, for the purpose of imparting shape retention. Useful inorganic powders can be dispersed in a photocrosslinkable photosensitive composition, and typical examples include colloidal silica, calcium carbonate, and titanium oxide. Also,
Examples of the polymer include a compound having a group capable of photodimerization, and a normal vinyl polymer, a (meth) acrylate polymer, an unvulcanized rubber, Ether, polyamide,
Polyester, polyurethane, epoxy resin, urea resin, alkyd resin, melamine resin, phenol resin, gum rosin, polyterpene, cumarone-indene resin, and mixtures thereof can be widely used.

The photopolymerizable or photocrosslinkable photosensitive composition may contain a diazo compound. The diazo compound is not particularly limited, and a known diazo compound can be used.

The above-mentioned photosensitive layer is formed by applying a coating solution in which each of the above-mentioned necessary components is dissolved in a solvent to the surface of a support or a lower photosensitive layer provided thereon and drying the coating to form a photosensitive layer. It is manufactured by

Solvents for dissolving the above components include methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether,
Diethylene glycol diethyl ether, diethylene glycol monoisopropyl ether, propylene glycol, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dicarboxylic acid methyl ether, dipropylene glycol methyl ethyl ether, ethyl formate, propyl formate Butyl formate, amyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, methyl ethyl ketone, cyclohexanone, methyl cyclohexanone, Diacetone alcohol,
Acetyl acetone, γ-butyrolactone and the like can be mentioned. These solvents can be used alone or in combination of two or more.

As a coating method, conventionally known spin coating,
Wire bar coating, dip coating, air knife coating,
Roll coating, blade coating, curtain coating and the like can be used.

The concentration of the coating solution is desirably in the range of 1 to 50% by weight. In this case, the coating amount of the coating liquid is generally appropriate in the range of about 0.2 to 10 g / m ² as a solid content.

In the invention according to claim 1 or 2, the two or more layers including the photosensitive layer include layers other than the photosensitive layer. An example of such a layer is an overcoat layer provided on the photosensitive layer. The overcoat layer is used for the purpose of protecting the surface of the photosensitive layer, has a film forming property, is dissolved in the washing water used in the washing step before development, and is provided on the radical polymerizable photosensitive layer. And a layer formed of a high molecular compound such as polyvinyl alcohol or acidic celluloses having an oxygen barrier property.

As the filler contained in the uppermost layer of these layers, known fillers can be used, and for example, tin sol, alumina, silica, titanium oxide and the like can be used. These can be used after surface treatment with AlO ₂ , SiO ₂ or the like.

In the invention according to claim 1, a filler is contained in the uppermost layer of the two or more layers coated on the support, and the dry thickness of the uppermost layer is 0.5 μm or less;
In addition, the average particle size of the filler is smaller than the dried film thickness of the uppermost layer. If the dry thickness of the uppermost layer exceeds 0.5 μm, sensitivity, printing durability and chemical resistance deteriorate, and if the average particle size of the filler is not smaller than the dry thickness of the uppermost layer, the printing durability , Chemical resistance, ballpoint pen residue, ballpoint pen tear, and coating properties all deteriorate.

In the invention according to the first aspect, "wet-on-wet" refers to a method of coating a plurality of layers on a support in a state where the applied lower layer is in a wet state while the upper layer is in a wet state. This refers to applying a coating solution.

As a coating apparatus used in this method, for example, a die coater as shown in FIGS. 1 (a) to 1 (c) can be used. 1 (a) to 1 (c), 1 is a support conveyed in the direction of an arrow, 2 is a lower layer, 3 is an upper layer,
Reference numeral 4 denotes a die coater, and 5 denotes a liquid pool.

In the invention according to claim 2, the average surface roughness (Ra), the 10-point average roughness (Rz) and the maximum surface roughness (Rmax) are measured values according to JIS surface roughness (B0601).

Ra, Rz and Rmax satisfy the above condition (1).
When Rz / Ra ≦ 8 and (2) Rmax / Ra ≦ 14 are not satisfied, all of the printing durability, chemical resistance, remaining ballpoint pen, ballpoint pen lurre, and coatability deteriorate.

According to the manufacturing method of the first aspect,
A photosensitive lithographic printing plate satisfying these conditions can be obtained.

[0045]

【Example】

(Preparation of Support) A 0.3 mm-thick aluminum plate (material 1050, tempered H16) was degreased in a 5% aqueous sodium hydroxide solution kept at 65 ° C. for 1 minute, and then washed with water. It was immersed in a 10% aqueous solution of sulfuric acid maintained at ℃ for 1 minute, neutralized, and further washed with water. This aluminum plate was used for 1.
In a 0 wt% aqueous hydrochloric acid solution, electrolytic surface roughening was performed by using an alternating current at a temperature of 25 ° C., a current density of 100 A / dm ² , and a processing time of 60 seconds. Next, a desmut treatment is performed in a 5% aqueous sodium hydroxide solution at 60 ° C. for 10 seconds, and then anodized in a 20% sulfuric acid solution at a temperature of 20 ° C., a current density of 3 A / dm ² and a treatment time of 1 minute. Processing was performed. Then, it was immersed in a 1% aqueous solution of sodium nitrite kept at 80 ° C. for 30 seconds, washed with water and dried at 80 ° C. for 3 minutes. Further, the substrate was immersed in an aqueous solution of carboxymethylcellulose (concentration: 0.1 wt%) maintained at 85 ° C. for 30 seconds, and dried at 80 ° C. for 5 minutes to prepare a support.

(Photosensitive solution A for the above) Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight average molecular weight: 4000) 6.7 g pyrogallol acetone resin (weight average molecular weight: 3000) Condensate of O-naphthoquinonediazide-5-sulfonyl chloride (esterification rate 30%) 1.5 g Polyethylene glycol # 2000 0.2 g Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.08 g 2,4-bis ( Trichloromethyl) -6- (p-methoxystyryl) -S-triazine 0.15 g FC-430 (manufactured by Sumitomo 3M) 0.03 g Cyclohexanone / methyl ethyl ketone = 70/30 100 ml Polymer compound 1 0.2 g TiO ₂ Dispersion (prepared using Dynomill with the following composition) 2 0 g TiO ₂ (AlO _2, SiO ₂ with a surface treatment: Al 2 wt% to 8 wt% Si with respect to TiO ₂ to TiO ₂₎ Average particle diameter: 0.25 [mu] m) novolac resin (phenol / m- cresol / p 0.85 g cyclohexanone / methyl ethyl ketone = 70/30 30 ml (lower layer photosensitive solution B) novolak resin (phenol / m-cresol / p-cresol molar ratio) Is 10/54/36, weight average molecular weight 4000) 6.7 g Condensation product of pyrogallol acetone resin (weight average molecular weight 3000) and O-naphthoquinonediazide-5-sulfonyl chloride (esterification ratio 30%) 1.5 g polyethylene glycol # 2000 0.2g Victoria Pure Blue BOH (Hodogaya 0.08 g 2,4-bis (trichloromethyl) -6- (p-methoxystyryl) -S-triazine 0.15 g FC-430 (Sumitomo 3M) 0.03 g Cyclohexanone / Methyl ethyl ketone = 70/30 100 ml Polymer compound 1 0.2 g Polymer compound 1 According to a conventionally known synthesis method, benzyl methacrylate / 4-hydroxyphenyl methacrylamide / acrylonitrile / methyl methacrylate / methacrylic acid =
Polymerization is carried out at a ratio of 30/20/30/15/5 to obtain the following polymer compound 1.

[0047]

Embedded image

(Preparation of Photosensitive Lithographic Printing Plate Sample) A coating solution B for the lower layer and a coating solution A for the upper layer are formed on the support as shown in FIG.
While the lower layer was in a wet state using a slit die coater, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The dry thickness of the photosensitive layer is 0.5 μm for the lower layer.
m, the upper layer was 0.3 μm.

Example 2 In Example 1, the following Sn was used instead of the TiO ₂ dispersion liquid.
The same coating solution as in Example 1 was used except that the O ₂ dispersion was used. The lower layer coating solution B and the upper layer coating solution A were coated on the support using a two-slit die coater shown in FIG. While in a wet state, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The photosensitive layer thickness of the lower layer is 0.5 μm.
m, the upper layer was 0.3 μm.

[0052] SnO ₂ dispersion (prepared using a Dyno mill with the following _{composition) 2.0g SnO 2 (AlO 2,} SiO 2 with a surface treatment: For TiO ₂ to 8 wt% Si and Al to TiO ₂ 2 wt% ) Average particle size: 0.25 μm) Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight average molecular weight: 4000) 0.85 g cyclohexanone / methyl ethyl ketone = 70/30 30 ml Example 3 In Example 1, the following Ti was used instead of the TiO ₂ dispersion.
The same coating solution as in Example 1 was used except that the O ₂ dispersion was used. The lower layer coating solution B and the upper layer coating solution A were coated on the support using a two-slit die coater shown in FIG. While in a wet state, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The thickness of the photosensitive layer is 0.5 μm for the lower layer.
m, the upper layer was 0.2 μm.

TiO ₂ dispersion (prepared using Dynomill with the following composition) 2.0 g TiO ₂ (Surface treatment with AlO ₂ , SiO ₂ : 8% by weight of Al with respect to TiO _{2 2} % by weight of Si with respect to TiO ₂ ) Average particle size: 0.15 μm) Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight average molecular weight: 4000) 0.85 g cyclohexanone / methyl ethyl ketone = 70/30 30 ml Example 4 In Example 1, the following Sn was used instead of the TiO ₂ dispersion.
The same coating solution as in Example 1 was used except that the O ₂ dispersion was used. The lower layer coating solution B and the upper layer coating solution A were coated on the support using a two-slit die coater shown in FIG. While in a wet state, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The photosensitive layer thickness of the photosensitive layer is 0.5 μm for the lower layer.
m, the upper layer was 0.3 μm.

[0056] SnO ₂ dispersion (prepared using a Dyno mill with the following _{composition) 2.0g SnO 2 (AlO 2,} SiO 2 with a surface treatment: For TiO ₂ to 8 wt% Si and Al to TiO ₂ 2 wt% ) Average particle size: 0.1 μm) Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight-average molecular weight: 4000) 0.85 g cyclohexanone / methyl ethyl ketone = 70/30 30 ml Example 5 In Example 1, the following Al ₂ was used instead of the TiO ₂ dispersion.
The same coating solution as in Example 1 was used except that the O ₃ dispersion was used. The lower layer coating solution B and the upper layer coating solution A were coated on the support using a two-slit die coater shown in FIG. While in a wet state, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The photosensitive layer thickness of the lower layer is 0.5 μm.
m, the upper layer was 0.3 μm.

[0058] Al ₂ O ₃ dispersion (prepared using a Dyno mill with the following _{composition) 2.0g Al 2 O 3 (ZrO} 2, SiO 2 with a surface treatment: Zr a to TiO ₂ to 8 wt% Si to TiO ₂ Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight average molecular weight: 4000) 0.85 g cyclohexanone / methyl ethyl ketone = 70/30 30 ml Comparative Example 1 Using the same coating as in Example 1, the lower layer coating solution B was coated on the above-mentioned support using a die coater, dried at 80 ° C., once wound up, and then coated with the upper layer coating solution. A was applied using a die coater and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample. In addition, the dry thickness of the photosensitive layer is 0.
5 μm and the upper layer was 0.3 μm.

Comparative Example 2 In Example 1, the following Ti was used instead of the TiO ₂ dispersion.
The same coating solution as in Example 1 was used except that the O ₂ dispersion was used. The lower layer coating solution B and the upper layer coating solution A were coated on the support using a two-slit die coater shown in FIG. While in a wet state, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The photosensitive layer thickness of the lower layer is 0.5 μm.
m, the upper layer was 0.3 μm.

[0061] TiO ₂ dispersion (prepared using a Dyno mill with the following _{composition) 2.0g TiO 2 (AlO 2,} SiO 2 with a surface treatment: the Al to TiO ₂ 8 wt% Si with respect to TiO ₂ 2 wt% ) Average particle size: 0.4 μm) Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight average molecular weight: 4000) 0.85 g cyclohexanone / methyl ethyl ketone = 30/30 30 ml Comparative Example 3 In Example 1, the following Sn was used instead of the TiO ₂ dispersion.
The same coating solution as in Example 1 was used except that the O ₂ dispersion was used. The lower layer coating solution B and the upper layer coating solution A were coated on the support using a two-slit die coater shown in FIG. While in a wet state, the upper layer was applied by a wet-on-wet method and dried at 80 ° C. to prepare a photosensitive lithographic printing plate sample.

The photosensitive layer thickness of the lower layer is 0.5 μm.
m, the upper layer was 0.3 μm.

[0063] SnO ₂ dispersion (prepared using a Dyno mill with the following _{composition) 2.0g SnO 2 (AlO 2,} SiO 2 with a surface treatment: For TiO ₂ to 8 wt% Si and Al to TiO ₂ 2 wt% ) Average particle size: 0.1 μm) Novolak resin (molar ratio of phenol / m-cresol / p-cresol: 10/54/36, weight average molecular weight: 4000) 0.85 g cyclohexanone / methyl ethyl ketone = 70/30 30 ml (evaluation method) ) = Sensitivity = A 4 kW metal halide lamp (Vio, manufactured by Dainippon Screen Co., Ltd.) is closely adhered to a sample with a sensitivity measurement step tablet (No. 2, manufactured by Eastman Kodak Co., Ltd., gray scale of 21 steps each having a density difference of 0.15). (Quick) as a light source from a distance of 90 cm. Next, this sample was developed at 27 ° C. for 20 seconds with a developer obtained by diluting an SDR-1 (manufactured by Konica) developer 6 times with water.

The sensitivity was defined as the exposure time at which 3.0 steps of the step tablet were completely cleared.

= Printing durability = A step tablet for sensitivity measurement (No. 2, manufactured by Eastman Kodak Co., Ltd., gray scale of 21 steps each having a density difference of 0.15) is closely attached to the sample, and a 4 kW metal halide lamp (Dainippon Screen ( Exposure was performed from a distance of 90 cm using "Vio Quick" (trade name, manufactured by Co., Ltd.) as a light source. Next, this sample was developed at 27 ° C. for 20 seconds with a developer obtained by diluting an SDR-1 (manufactured by Konica) developer 6 times with water.

The obtained lithographic printing plate was applied to a printing machine GRO manufactured by Heidelberg Co., Ltd., and coated paper, printing ink (New Bright Red manufactured by Toyo Ink Mfg. Co., Ltd.) and fountain solution (SEU-3 manufactured by Konica; 2. 5%), and printing was continued until an incomplete deposit appeared on a solid portion of an image of the printed matter or ink was deposited on a non-image portion, and the number of printed sheets at that time was counted.

= Remaining Ballpoint Pen = Drawing is performed using a pilot oil-made ballpoint pen while applying a load of 50 g to the sample. Thereafter, exposure was performed from a distance of 90 cm using a 4 kW metal halide lamp (bio Quick manufactured by Dainippon Screen Co., Ltd.) as a light source. Next, this sample was developed at 27 ° C. for 20 seconds with a developer obtained by diluting an SDR-1 (manufactured by Konica) developer 6 times with water. The remaining state of the ballpoint pen ink was visually evaluated.

：: Ballpoint pen ink is not completely left Δ: Ballpoint pen ink is left in some places ×: Ballpoint pen ink is completely left

= Ball Pen Yarare = A sample is drawn using a pilot oil-made ballpoint pen while applying a load of 50 g to the sample. Next, this sample was developed at 27 ° C. for 20 seconds with a developer obtained by diluting an SDR-1 (manufactured by Konica) developer 6 times with water. Visual evaluation was performed on the photosensitive layer in the drawing area of the ballpoint pen ink to determine the degree of vignetting.

：: No damage to the photosensitive layer Δ: Part of the photosensitive layer disappeared and grain was exposed ×: The photosensitive layer was completely eliminated and grain was exposed.

Evaluation of Chemical Resistance The obtained photosensitive lithographic printing plate was used as a light source with a 4 kW metal halide lamp, and a 50% flat screen original was closely adhered to the lithographic printing plate.
Exposure was performed by irradiating with mW / cm ² for 60 seconds.
The exposed photosensitive lithographic printing plate was developed with a commercially available developer (SDR-1, manufactured by Konica Corporation, diluted 6 times, development time 20 seconds, development temperature 27 ° C.). The obtained lithographic printing plate was immersed in an ultraplate cleaner (manufactured by ABC Chemical Co., Ltd.), and the time when the image area began to be damaged was evaluated.

Evaluation of coatability The state of the coat was visually determined.

：: No coating streak occurred. Δ: Coating streak occurred partially. ×: A large amount of coating streak occurred.

Evaluation of Ra, Rz, Rmax Ra, Rz, Rmax were measured with a tertiary element roughness meter (3FK) manufactured by Kosaka Laboratory (cutoff was 0.25 m).
m). The definitions of Ra, Rz, and Rmax are based on JIS surface roughness (B0601).

The results are shown in Table 1 below.

[0076]

[Table 1]

[0077]

According to the present invention, there is provided a photosensitive lithographic printing plate having improved pen developability, printing durability, and chemical resistance, in which ball-point pen residue and ball-point pen tear are improved, and a method for producing the same. Further, in particular, there is provided a photosensitive lithographic printing plate capable of obtaining the above-mentioned effects when the photosensitive layer is made thinner in order to reduce the processing waste liquid and to speed up the processing, and a method for producing the same. Further, according to the first aspect of the invention, the coating property of the coating layer on the support is improved.

[Brief description of the drawings]

FIG. 1 is a schematic view of a die coater which is an example of a coating apparatus used in the manufacturing method of claim 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support 2 Lower layer 3 Upper layer 4 Die coater 5 Liquid reservoir

Claims (2)

[Claims] 1. A method for producing a photosensitive lithographic printing plate comprising providing a support with two or more coating layers including a photosensitive layer containing a compound capable of generating an acid or a radical by light, actinic radiation or electron beam. A filler having an average particle diameter smaller than the dry thickness of the uppermost layer is contained in the uppermost layer of the coating layers, the dry thickness of the uppermost layer is set to 0.5 μm or less, and the uppermost layer, A method for producing a photosensitive lithographic printing plate, comprising applying at least one of the coating layers other than the uppermost layer by a wet-on-wet method. 2. A photosensitive lithographic printing plate having, on a support, at least two layers including a photosensitive layer containing a compound capable of generating an acid or a radical by light, actinic radiation or electron beam. The average surface roughness (Ra), the 10-point average roughness (Rz), and the maximum surface roughness (Rmax) of the uppermost layer among the two or more layers satisfy the following conditions (a) and (b). Features a photosensitive lithographic printing plate. (A) Rz / Ra ≦ 8 (b) Rmax / Ra ≦ 14