JPH0798499A - Photosensitive lithographic printing plate - Google Patents

Abstract

PURPOSE:To provide a photosensitive lithographic printing plate having good sensitivity, contrast and printing durability, excellent in ball-point pen and cellophane adhesive tape adaptability, without the foreign matter and sludge being accumulated in developer and without contaminating the developer. CONSTITUTION:A photosensitive layer contg. an o-quinone diazide compd. and the layer contg. triphenylsulfonium trifluoromethanesulfonate or bisphenyliodonium trifluoromethanesulfonate are provided on a substrate of aluminum or its alloy which has been anodized and then treated with an aq. nitrite soln. to constitute the plate.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photosensitive lithographic printing plate.

[0002]

BACKGROUND OF THE INVENTION A photosensitive lithographic printing plate is one in which an ink-receptive photosensitive layer is provided on a hydrophilic support. For example, in a positive type photosensitive lithographic printing plate, an ultraviolet ray or the like is provided on the hydrophilic support. And an ink-receptive photosensitive layer that is solubilized by exposure to actinic rays.

When the photosensitive layer of such a positive-working photosensitive lithographic printing plate is imagewise exposed from an original film and then developed, the exposed photosensitive layer is removed and the surface of the hydrophilic support is exposed. The unexposed portions of the photosensitive layer remain on the support to form an ink receiving layer. In lithographic printing, the difference in properties that the exposed portion is hydrophilic and the unexposed portion is lipophilic is used.

However, a problem when image-wise exposing a photosensitive lithographic printing plate from an original film is that the environment for image-wise exposure is not necessarily clean. for that reason,
Inevitably, foreign matter such as dust adheres to the original film or the photosensitive lithographic printing plate. When foreign matter such as dust adheres to the original film or the photosensitive lithographic printing plate, a very small amount of light enters from the adhered portion, a sharp resist image cannot be formed, and there is a possibility that a blur phenomenon occurs.

Further, when the photosensitive lithographic printing plate is exposed and developed under a white lamp (fluorescent lamp, etc.) for a long time (about 10 minutes), the unexposed portion of the photosensitive lithographic printing plate is also developed. , There was a problem that the film thickness of the photosensitive layer of the printing plate was reduced. In order to avoid these problems, it was necessary to enhance the safelight property of the photosensitive lithographic printing plate.

Therefore, even if foreign matter such as dust adheres to the original film or the photosensitive lithographic printing plate, a sharp resist image can be obtained, and the photosensitivity is excellent in the high contrast so that the safelight property can be enhanced. Development of lithographic printing plate is in progress.

Further, when performing so-called multi-sided printing in which the positions of a plurality of original films are changed and printed one after another on the photosensitive lithographic printing plate, the positions of the originals are marked on the photosensitive layer for alignment between the original films. Is often done. As a writing instrument for marking, an oil-based ballpoint pen is usually used.However, when marking is done with an oil-based ballpoint pen, the solvent of the oil-based ballpoint pen ink erodes the photosensitive layer of the photosensitive lithographic printing plate, and the photosensitive layer There is a problem that is dissolved. Especially when the marked part is the image part, if the developing process is performed as it is, the photosensitive layer of the mark part of the image part is removed, and the mark mark is reproduced on the printed matter at the time of printing. It is desired to develop a photosensitive lithographic printing plate which is not corroded by the solvent of the above ink, that is, has a suitability for a ballpoint pen.

Further, when the original film is printed on the photosensitive lithographic printing plate, a cellophane adhesive tape may be directly stuck on the photosensitive lithographic printing plate in order to fix the original film or to expose it in an overlapping manner. Many are done. These cellophane adhesive tapes are peeled off after baking the original film, but it is unavoidable that the adhesives of the cellophane adhesive tapes remain on the photosensitive lithographic printing plate, and if the adhesives remain on the photosensitive lithographic printing plate. Since it causes development failure and stains on the plate surface at the time of printing, it does not cause development failure even after peeling the attached cellophane adhesive tape,
That is, development of a photosensitive lithographic printing plate suitable for cellophane adhesive tape is desired.

The support of the photosensitive lithographic printing plate has abrasion resistance,
In order to improve chemical resistance and water retention, a roughening treatment is usually performed, and an oxide film is formed by anodizing treatment.This oxide film dissolves in a strongly alkaline developing solution. It dissolves in it and accumulates in the developer to form dust or sludge, which contaminates the developer.
In order to prevent the dissolution of these oxide films, post-treatment for sealing the anodic oxide film is performed.

Conventionally, in order to improve the contrast, the o-quinonediazide compound used has a high molecular weight and the alkali-soluble resin has a high molecular weight. In both cases, the sensitivity of the photosensitive lithographic printing plate has been improved. However, there was a problem that

In order to improve suitability for ballpoint pens and cellophane adhesive tapes, it has been customary to add a fluorine-based surfactant or a nonionic surfactant to the photosensitive layer. When added in a large amount in order to improve suitability for a ballpoint pen and cellophane adhesive tape, there is a problem that the sensitivity of the photosensitive lithographic printing plate is lowered or the developability is deteriorated.

As the sealing treatment for preventing the dissolution of the oxide film, sealing treatment with hot water or sealing treatment with an aqueous nitrite solution is carried out. With the body, for the purpose of improving sensitivity,
When an organic acid is added, the molecular weight of the o-quinonediazide compound fat is reduced, and the alkali-soluble resin is reduced in molecular weight, the contrast becomes poor and the printing durability is also reduced.

[0013]

SUMMARY OF THE INVENTION Accordingly, the object of the present invention is to provide good sensitivity, high contrast, printing durability, excellent ballpoint pen suitability and cellophane adhesive tape suitability, and further to prevent development of dust and sludge in the developer. It is to provide a photosensitive lithographic printing plate free from liquid contamination.

[0014]

The above objects of the present invention are as follows: (1) A support made of aluminum or its alloy, which has been anodized and then treated with an aqueous nitrite solution, has (a) an o-quinonediazide compound and ( b) A photosensitive lithographic printing plate comprising a photosensitive layer containing triphenylsulfonium trifluoromethanesulfonic acid or bisphenyliodonium trifluoromethanesulfonic acid. (2) The photosensitive lithographic printing plate as described in (1) above, wherein the surface of the support is roughened prior to the anodizing treatment. Can be achieved by

The present invention will be described in detail below.

First, a photosensitive layer containing (a) an o-quinonediazide compound and (b) triphenylsulfonium trifluoromethanesulfonic acid or bisphenyliodonium trifluoromethanesulfonic acid (hereinafter referred to as a photosensitive layer of the present invention) will be described. .

The o-quinonediazide compound is a compound having an o-quinonediazide group in the molecule, and the o-quinonediazide compound used in the photosensitive layer of the present invention is an o-naphthoquinonediazide compound such as o-quinonediazide compound. Examples thereof include ester compounds of naphthoquinone diazide sulfonic acid and a polycondensation resin of phenols and aldehydes or ketones.

Examples of the phenols in the polycondensation resin with the above-mentioned phenols and aldehydes or ketones include phenol, o-cresol, m-cresol,
Examples include monohydric phenols such as p-cresol, 3,5-xylenol, carvacrol, thymol, dihydric phenols such as catechol, resorcin, and hydroquinone, and trihydric phenols such as pyrogallol and phloroglucin. Examples of the aldehyde include formaldehyde,
Examples thereof include benzaldehyde, acetaldehyde, crotonaldehyde, furfural and the like. Of these, preferred are formaldehyde and benzaldehyde. Examples of ketones include acetone and methyl ethyl ketone.

Specific examples of polycondensation resins with phenols and aldehydes or ketones include phenol-formaldehyde resin, m-cresol-formaldehyde resin, m- and p-mixed cresol-formaldehyde resin, resorcin-benzaldehyde resin, Examples include pyrogallol / acetone resin.

In the o-naphthoquinonediazide compound, the condensation rate of o-naphthoquinonediazide sulfonic acid with respect to the OH groups of phenols (reaction rate with respect to one OH group) is preferably 15% to 80%, more preferably 2
It is 0% to 45%.

Further, as the o-quinonediazide compound used in the present invention, the following compounds described in JP-A-58-43451 can also be mentioned. That is, for example, 1,2-benzoquinone diazide sulfonic acid ester, 1,2-naphthoquinone diazide sulfonic acid ester, 1,2-benzoquinone diazide sulfonic acid amide,
Known 1,2-quinonediazide compounds such as 1,2-naphthoquinonediazide sulfonic acid amide, and more specifically, J. Kosar "Light-Sensitive Systems" No. 339. Pp. 352 (1965), John Willie
And Sons (John Willey & Sons) (New York) and W S De Forest (WSDe For
est) "Photoresist" Volume 50,
(1975), 1,2-benzoquinonediazide-4-sulfonic acid phenyl ester, 1, described in McGrawHi1l (New York), 1,
2,1 ′, 2′-di- (benzoquinonediazide-4-sulfonyl) -dihydroxybiphenyl, 1,2-benzoquinonediazide-4- (N-ethyl-N-β-naphthyl) -sulfonamide, 1,2- Naphthoquinonediazide-5-sulfonic acid cyclohexyl ester, 1- (1,
2-naphthoquinonediazide-5-sulfonyl) -3,5
-Dimethylpyrazole, 1,2-naphthoquinonediazide-5-sulfonic acid-4'-hydroxydiphenyl-4 '
-Azo-β-naphthol-ester, N, N-di-
(1,2-naphthoquinonediazide-5-sulfonyl)-
Aniline, 2 '-(1,2-naphthoquinonediazide-5
-Sulfonyloxy) -1-hydroxy-anthraquinone, 1,2-naphthoquinonediazide-5-sulfonic acid-
2,4-dihydroxybenzophenone ester, 1,2
-Naphthoquinonediazide-5-sulfonic acid-2,3,4
-Trihydroxybenzophenone ester, a condensate of 1,2-naphthoquinonediazide-5-sulfonic acid chloride 2 mol and 4,4'-diaminobenzophenone 1 mol,
Condensation product of 2,2-naphthoquinonediazide-5-sulfonic acid chloride (2 mol) and 4,4'-dihydroxy-1,1'-diphenylsulfonic acid (1 mol), 1,2-naphthoquinonediazide-5-sulfonic acid chloride (1) Examples thereof include 1,2-quinonediazide compounds such as a condensate of 1 mol of purpurogallin and 1,2-naphthoquinonediazide-5- (N-dihydroabietyl) -sulfonamide. In addition, Japanese Examined Patent Publication Nos. 37-1953 and 37-362
No. 7, No. 37-13109, No. 40-26126,
40-3801, 45-5604, 45-2
No. 7345, No. 51-13013, JP-A-48-96.
No. 575, No. 48-63802, No. 48-63803.
The 1,2-quinonediazide compounds described in each publication can also be mentioned.

Of the above o-quinonediazide compounds,
An o-quinone diazide ester compound obtained by reacting 1,2-benzoquinone diazide sulfonyl chloride or 1,2-naphthoquinone diazide sulfonyl chloride with pyrogallol-acetone condensation resin or 2,3,4-trihydroxybenzophenone is particularly preferable.

In the photosensitive layer of the present invention, as the o-quinonediazide compound, the above compounds may be used alone or in combination of two or more kinds.

Next, triphenylsulfonium trifluoromethanesulfonic acid and bisphenyliodonium trifluoromethanesulfonic acid will be described.

The above-mentioned triphenylsulfonium trifluoromethanesulfonic acid is preferably a compound containing one or more methoxy groups in the triphenylsulfonium cation part. Moreover, as the bisphenyliodonium trifluoromethanesulfonic acid, bis (tert-butylphenyl) iodonium trifluoromethanesulfonic acid is preferable. The content of these compounds in the photosensitive composition is preferably 0.01 to 10% by weight, more preferably 0.1 to 5% by weight.

It is preferable that an alkali-soluble resin is further added to the photosensitive composition forming the photosensitive layer of the present invention.

Examples of these alkali-soluble resins include novolak resins, vinyl polymers having phenolic hydroxyl groups, condensation resins of polyhydric phenols and aldehydes or ketones described in JP-A-55-57841. To be

Examples of the novolac resin include phenol / formaldehyde resin, cresol / formaldehyde resin, phenol / cresol / formaldehyde copolymer resin as described in JP-A-55-57841, JP-A-55. Examples thereof include copolymer resins of p-substituted phenol and phenol or cresol and formaldehyde as described in JP-A-127553.

The novolak resin preferably has a number average molecular weight Mn of 3.00 × 10 (polystyrene standard).
^{2 to} 7.50 × 10 ³ , weight average molecular weight Mw of 1.00 ×
10 ^{3 to} 3.00 × 10 ⁴ , more preferably Mn of 5.0
0 × 10 ^{2 to} 4.00 × 10 ³ , Mw of 3.00 × 10 ^3.
˜2.00 × 10 ⁴ .

The above novolak resins may be used alone or in combination of two or more kinds.

The proportion of the novolak resin in the photosensitive composition is preferably 5 to 95% by weight.

The above-mentioned vinyl polymer having a phenolic hydroxyl group used in the present invention is a polymer having a unit having a phenolic hydroxyl group in its molecular structure,
A polymer containing at least one structural unit represented by the following general formulas [I] to [V] is preferable.

[0033]

[Chemical 1]

In the general formulas [I] to [V], R
₁ and R ₂ each represent a hydrogen atom, an alkyl group or a carboxyl group, preferably a hydrogen atom. R ₃
Represents a hydrogen atom, a halogen atom or an alkyl group, preferably a hydrogen atom or an alkyl group such as a methyl group or an ethyl group. R ₄ represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and preferably a hydrogen atom.
A represents an alkylene group, which connects a nitrogen atom or an oxygen atom and an aromatic carbon atom, and may have a substituent,
m represents an integer of 0 to 10, and B represents a phenylene group which may have a substituent or a naphthylene group which may have a substituent.

The vinyl polymer having a phenolic hydroxyl group used in the present invention preferably has a copolymer type structure, and has a structure represented by each of the above general formulas [I] to [V]. As the monomer to be copolymerized with the unit, for example, ethylene, propylene, isobutylene, butadiene, isoprene and other ethylenically unsaturated offylenes, for example, styrene, α-methylstyrene,
Styrenes such as p-methylstyrene and p-chlorostyrene, acrylic acids such as acrylic acid and methacrylic acid, and unsaturated aliphatic dicarboxylic acids such as itacone, maleic acid and maleic anhydride, such as methyl acrylate , Ethyl acrylate, -n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, ethyl ethacrylate, etc. Α-methylene aliphatic monocarboxylic acid esters, for example, nitriles such as acrylonitrile and methacrylonitrile, amides such as acrylamide, for example, acrylanilide, p-chloroacrylanilide, m-nitroacrylanilide, m -Methoxy Anilides such as acrylic anilide, for example, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl acetate, etc., vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, β-chloroethyl vinyl ether, chloride Vinyl, vinylidene chloride, vinylidene cyanide, for example, 1-methyl-1-methoxyethylene, 1,1-dimethoxyethylene, 1,2-dimethoxyethylene, 1,1-dimethoxycarbonylethylene, 1-methyl-1-nitro Ethylene derivatives such as ethylene, for example, N-vinylpyrrole,
N-vinylcarbazole, N-vinylindole, N-
There are N-vinyl monomers such as vinylpyrrolidene and N-vinylpyrrolidone. These monomers are present in the polymer compound in a structure in which the unsaturated double bond is cleaved.

Of the above-mentioned monomers, aliphatic monocarboxylic acid esters and nitriles are preferable because they exhibit excellent performance for the purpose of the present invention.

These monomers may be bound to the polymer used in the present invention in either a block or random state.

The proportion of the vinyl polymer having a phenolic hydroxyl group in the photosensitive composition is preferably 0.5 to 70% by weight.

As the vinyl polymer having a phenolic hydroxyl group, the above polymers may be used alone or in combination of two or more kinds. It can also be used in combination with other polymer compounds.

When an alkali-soluble resin is used in combination, o-
The proportion of the quinonediazide compound in the photosensitive composition is preferably 5 to 60% by weight, particularly preferably 10 to 50% by weight.

A printout material capable of forming a visible image upon exposure can be added to the photosensitive composition. The printout material is composed of a compound which forms an acid or a free radical upon exposure to light and an organic dye which changes its color tone by interacting with the generated acid or a free radical. Examples thereof include o-naphthoquinonediazide-4-sulfonic acid halogenide described in JP-A-50-36209, trihalomethyl-2-pyrone and trihalomethyl-triazine described in JP-A-53-362223, An ester compound or amide compound of o-naphthoquinonediazide-4-sulfonic acid chloride and a phenol or aniline having an electron-withdrawing substituent described in JP-A-55-6244, JP-A-55-77742.
And halomethylvinyloxadiazole compounds and diazonium salts described in JP-A-57-148784 and the like.

As the organic dye, Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.), Patent Pure Blue (manufactured by Sumitomo Mikuni Chemical Co., Ltd.), Oil Blue # 603 (manufactured by Orient Chemical Co., Ltd.) , Sudan blue II (manufactured by BASF), crystal violet, malachite green, fuchsin, methyl violet, ethyl violet, methyl orange, brilliant green, congo red, eosin, rhodamine 6
6 etc. can be mentioned.

In addition to the above-mentioned materials, a plasticizer, a surfactant, an organic acid, an acid anhydride and the like can be added to the photosensitive composition, if necessary.

Further, in order to improve the oil sensitivity of the photosensitive composition used in the present invention, for example, p-tert-butylphenolformaldehyde resin, pn-octylphenolformaldehyde resin or these is used. It is also possible to add a resin in which the above resin is partially estylated with an o-quinonediazide compound.

The photosensitive layer of the present invention can be formed by coating a support with a coating solution prepared by dissolving a photosensitive composition comprising each of these components in a solvent and drying the coating solution.

Solvents that can be used to dissolve these photosensitive compositions include, for example, 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 dimethyl ether, dipropylene glycol methyl ethyl ether,
Ethyl formate, propyl formate, butyl formate, amyl formate,
Methyl acetate, ethyl acetate, propyl acetate, butyl acetate,
Examples thereof include methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, methyl ethyl ketone, cyclohexanone, methylcyclohexanone, diacetone alcohol, acetylacetone, γ-butyrolactone and the like. These solvents may be used alone or in admixture of two or more.

The coating method used for coating the surface of the support with the photosensitive composition is a conventionally known method, for example, spin coating, wire bar coating, dip coating, air knife coating, spray coating, air spray coating, Methods such as electrostatic air spray coating, roll coating, blade coating and curtain coating are used.

The coating amount varies depending on the use, but for example, a coating amount of 0.05 g to 5.0 g / m ² as a solid content is preferable.

In the present invention, a support made of aluminum or its alloy which has been anodized and then treated with an aqueous nitrite solution is used as the support. In addition, the surface of the support is preferably roughened prior to the anodizing treatment.

Usually, since oil and fat components such as rolling oil adhere to the surface of a plate made of aluminum or its alloy, degreasing treatment is performed to remove these oil and fat components.

As the degreasing treatment, a degreasing treatment using a solvent such as trichlene and thinner, for example, an emulsion degreasing treatment using an emulsion of kerosene and triethanol is used. Further, in order to remove stains and oxide films that cannot be removed only by degreasing, an alkaline solution such as a caustic soda aqueous solution having a concentration of 1% to 10% should be added at 5 ° C to 5 ° C at 5 ° C.
It is possible to use a method of dipping for 10 seconds to 10 minutes, and then dipping in an acidic solution such as nitric acid or sulfuric acid having a concentration of 10 to 20% at 10 ° C. to 50 ° C. for 5 seconds to 5 minutes.

The surface of the support is roughened in order to improve the adhesion to the photosensitive layer and to improve the water retention property. The surface can be roughened by graining. . Roughening methods for the surface of the support are well known, and any of these roughening methods can be used in the present invention.

As the graining method, for example, a so-called mechanical graining method of mechanically roughening the surface,
A so-called electrochemical surface-roughening method for electrochemically roughening the surface can be mentioned. The mechanical surface roughening method includes, for example, ball polishing, brush polishing, blast polishing, buff polishing, and the like, and the electrochemical surface roughening method includes, for example, an electrolytic solution containing hydrochloric acid or nitric acid. Among them, there is a method of electrolytically treating with AC or DC.

By the graining treatment, smuts are formed on the surface of the support. These smuts can be removed by washing with water or alkali etching. For removing smut, for example, the alkali etching method described in JP-B-48-28123 or the sulfuric acid desmutting method described in JP-A-53-12739 can be used.

The anodic oxidation treatment is carried out in order to form an oxide film on the support and improve abrasion resistance, chemical resistance and water retention. In the anodizing treatment, generally, an aqueous solution containing sulfuric acid and / or phosphoric acid or the like at a concentration of 10 to 50% is used as an electrolytic solution and a current density is 1 to 10 A / dm ^2.
A method of electrolyzing in sulfuric acid described in US Pat. No. 1,412,768 at high current density and US Pat. No. 3,511,6 are preferably used.
The method of electrolyzing with phosphoric acid described in the specification of No. 61 can also be used.

In the present invention, the above-mentioned pretreatment is followed by treatment with an aqueous nitrite solution.

Examples of the nitrite used in the treatment with the aqueous nitrite solution include Ia and II of the periodic table.
Mention may be made of nitrites or ammonium nitrites of metals of the groups a, IIb, IIIb, IVa, IVb, VIa, VIIa, VIII. Examples of the metal nitrite include LiN
O ₂ , NaNO ₂ , KNO ₂ , Mg (NO ₂ ) ₂ , Ca (N
O ₂ ) ₂ , Zn (NO ₂ ) ₂ , Al (NO ₂ ) ₃ , Zr (NO
₂ ) ₄ , Sn (NO ₂ ) ₄ , Cr (NO ₂ ) ₃ , Co (N
O ₂ ) ₂ , Mn (NO ₂ ) ₂ and Ni (NO ₂ ) ₂ are preferable, and alkali metal nitrite is particularly preferable. Such nitrites may be used alone or in combination of two or more. Further, it can be used in combination with nitrous acid.

The aqueous nitrite solution used in the above treatment preferably contains 0.001 to 10% by weight of nitrite in the aqueous solution.

For the treatment of the support with the nitrite aqueous solution, the support to be treated is immersed in the nitrite aqueous solution kept at room temperature to 100 ° C. for 3 to 300 seconds, or the support is coated with the nitrite aqueous solution. Is preferably performed.

Further, the support is added to an aqueous solution having a nitrite concentration of 0.1 to 2% by weight kept at 70 to 95 ° C. for 5 to 60%.
It is preferable to immerse for a second for treatment. Ultrasonic waves may be applied during the treatment to enhance the effect of the nitrite treatment,
In addition, the support may be immersed in hot water or an alkaline aqueous solution at 80 to 95 ° C before the treatment.

The photosensitive lithographic printing plate of the present invention can be exposed and developed by a conventionally used method.
For example, a transparent original image having a line image, a halftone dot image, etc. is brought into close contact with the photosensitive surface for exposure, and then the photosensitive layer in the non-image area is removed using an appropriate developing solution to obtain a relief image. . Suitable light sources for exposure include mercury lamps, metal halide lamps, xenon lamps, chemical lamps,
Carbon arc lamps and the like, and the developer used for development is preferably an alkaline aqueous solution, for example, sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, sodium triphosphate, diphosphoric acid. An aqueous solution of sodium, sodium carbonate, potassium carbonate, etc. may be mentioned. The concentration of the alkaline aqueous solution at this time varies depending on the type of the photosensitive composition and the alkali, but is generally in the range of 0.1 to 10% by weight. It is also possible to add an organic solvent such as alcohol or the like.

[0062]

【Example】

Example 1 [Preparation of Support] <Preparation of Support A> An aluminum plate having a thickness of 0.3 mm (material 1050, tempered H16) was immersed in a 5% sodium hydroxide aqueous solution kept at 65 ° C. After degreasing treatment for 1 minute, it was washed with water. This degreased aluminum plate is
It was immersed in a 10% sulfuric acid aqueous solution kept at 0 ° C for 1 minute for neutralization and then washed with water. Then, this aluminum plate is 1.0
Electrolytic surface roughening was performed for 60 seconds with an alternating current in a weight% hydrochloric acid aqueous solution at a temperature of 25 ° C. and a current density of 100 A / dm ² , and then 10% in a 5% sodium hydroxide aqueous solution kept at 60 ° C. A desmut treatment for 2 seconds was performed. Then, in a 20% sulfuric acid solution, the temperature was 20 ° C. and the current density was 3 A /
Anodizing treatment was performed for 1 minute under the condition of dm ² . Furthermore, 9
A support A was prepared by immersing in a 0.5 wt% sodium nitrite aqueous solution kept at 0 ° C. for 10 seconds, washing with water, and drying at 80 ° C. for 5 minutes.

<Preparation of Support B> An aluminum plate (material 1050, temper H16) having a thickness of 0.3 mm is immersed in a 5% sodium hydroxide aqueous solution kept at 65 ° C. and degreased for 1 minute. After going, it was washed with water. The degreased aluminum plate was immersed in a 10% sulfuric acid aqueous solution kept at 25 ° C. for 1 minute for neutralization and then washed with water. Then, the aluminum plate was placed in a 1.0 wt% hydrochloric acid aqueous solution at a temperature of 25
6 by AC current under conditions of ℃ and current density of 100A / dm ^2.
After electrolytic surface roughening for 0 second, desmut treatment was performed for 10 seconds in a 5% sodium hydroxide aqueous solution kept at 60 ° C. Then, anodizing treatment was performed for 1 minute in a 20% sulfuric acid solution at a temperature of 20 ° C. and a current density of 3 A / dm ² . Then, it was immersed in hot water of 30 ° C. for 20 seconds and dried at 80 ° C. for 5 minutes to prepare a support B.

[Preparation of photosensitive lithographic printing plate sample] Coating solutions 1 to 4 of the following photosensitive compositions were coated on the above-mentioned supports A and B using a wire bar and dried at 80 ° C. for 2 minutes, Photosensitive planographic printing plate samples 1 to 5 were obtained. Table 1 shows the type of support, the type of photosensitive composition coating liquid, and the type of compound used for each sample.

(Samples 1 and 5) <Photosensitive Composition Coating Liquid 1> Compound (I) 0.1 g o-quinonediazide-5-sulfonyl chloride and an ester of pyrogallol-acetone resin (weight average molecular weight 3000) (condensation rate) 30%) 1.0 g Novolac resin (molar ratio of phenol / m-cresol / p-cresol is 10/54/36, weight average molecular weight 4000) 6.7 g Polyethylene glycol # 2000 0.2 g Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd. 0.08 g 2,4-bis (trichloromethyl) -6- (p-methoxystyryl) -s-triazine 0.15 g FC-430 (Sumitomo 3M Co., Ltd.) 0.03 g Methyl Cellosolve 100 ml

(Sample 2) <Photosensitive Composition Coating Liquid 2> Compound (II) 0.1 g O-quinonediazide-5-sulfonyl chloride ester with pyrogallol-acetone resin (weight average molecular weight 3000) (condensation rate 30% ) 1.0 g Novolac resin (molar ratio of phenol / m-cresol / p-cresol is 10/54/36, weight average molecular weight 4000) 6.7 g Polyethylene glycol # 2000 0.2 g Victoria Pure Blue BOH (Hodogaya Chemical ( 0.08 g 2,4-bis (trichloromethyl) -6- (p-methoxystyryl) -s-triazine 0.15 g FC-430 (Sumitomo 3M Co., Ltd.) 0.03 g Methyl Cellosolve 100 Milliliter

(Sample 3) <Photosensitive Composition Coating Liquid 3> Ester of Compound (III) 0.1 g o-quinonediazide-5-sulfonyl chloride and pyrogallol-acetone resin (weight average molecular weight 3000) (condensation rate 30% ) 1.0 g Novolac resin (molar ratio of phenol / m-cresol / p-cresol is 10/54/36, weight average molecular weight 4000) 6.7 g Polyethylene glycol # 2000 0.2 g Victoria Pure Blue BOH (Hodogaya Chemical ( 0.08 g 2,4-bis (trichloromethyl) -6- (p-methoxystyryl) -s-triazine 0.15 g FC-430 (Sumitomo 3M Co., Ltd.) 0.03 g Methyl Cellosolve 100 Milliliter

(Sample 4) <Photosensitive Composition Coating Liquid 4> Ester of o-quinonediazide-5-sulfonyl chloride and pyrogallol-acetone resin (weight average molecular weight 3000) (condensation rate 30%) 1.0 g Novolak resin ( Phenol / m-cresol / p-cresol molar ratio is 10/54/36, weight average molecular weight 4000) 6.7 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 (Sumitomo 3M Ltd.) 0.03 g Methyl Cellosolve 100 ml

[0069]

[Chemical 1]

[0070]

[Table 1]

With respect to each of the obtained lithographic printing plate samples 1 to 5, the number of clear steps, the high contrast property, and the
Printing durability, ballpoint pen suitability, cellophane adhesive tape suitability,
The accumulation of dust and sludge and the elution amount of aluminum were evaluated. The obtained results are shown in Table 2.

[Evaluation Method] <Evaluation of the number of clear steps> On a photosensitive lithographic printing plate sample, a step tablet for sensitivity measurement (manufactured by Eastman Kodak Co., Ltd.)
No. 2, a gray scale of 21 steps with a density difference of 0.15 each was closely attached, and a 6 Kw metal halide lamp was used as a light source, and irradiation was performed for 60 seconds (vacuum drawing for 20 seconds) for exposure. Next, this sample was diluted with a developer obtained by diluting SD-32 (manufactured by Konica Corporation) developer 5 times with water.
Development was carried out at 5 ° C for 30 seconds to obtain a lithographic printing plate. From the grayscale developed image of the lithographic printing plate thus obtained, the number of clear stages that were completely developed was determined. The larger this value, the better the sensitivity.

<Evaluation of Hardness> From the grayscale developed image of the planographic printing plate obtained in the evaluation of the clear step number, the solid step number which is not completely developed and the clear step number which is completely developed are determined to obtain [solid step number]. Hardness was evaluated from the value of [clear stage number]. The smaller this value, the better the contrast.

<Evaluation of printing durability> The planographic printing plate obtained in the above evaluation of the number of clear steps is applied to a printing machine (printing machine GTO manufactured by Heidelberg Co.), and coated paper and printing ink (High Plus manufactured by Toyo Ink Mfg. Co., Ltd.) Printing is performed using M red) and dampening water (Konica Corp. SEU-3; 2.5%), and defective inking appears in the solid part of the image part of the printed matter or ink is applied to the non-image part. Printing was continued until the sheet was inked and the number of printed sheets at that time was determined to evaluate printing durability.

<Evaluation of suitability for ballpoint pen> A register mark was drawn on a photosensitive lithographic printing plate sample with a register mark drawing machine and developed after 2 minutes, and suitability for the ballpoint pen was evaluated according to how the photosensitive layer of the register mark was damaged by the ballpoint pen. ○: The image area is not affected at all ×: The image area is affected and the support is exposed

<Evaluation of Suitability of Cellophane Adhesive Tape> Cellophane adhesive tape was attached to a photosensitive lithographic printing plate sample to obtain 24
After leaving it for a while, it is peeled off, exposed and developed. The suitability of the cellophane adhesive tape was evaluated based on the degree of poor development at the place where the cellophane adhesive tape was attached. ○: No effect at all ×: Poor development observed

<Evaluation of accumulation of dust and sludge and elution amount of aluminum> After exposing the photosensitive lithographic printing plate sample to 5 m ² of the photosensitive lithographic printing plate sample per 1 liter of the developing solution, The accumulation of residue and sludge was evaluated. ◯: No accumulation is observed ×: Accumulation is observed Further, the elution amount of aluminum was measured by ICP emission spectrometry.

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[Table 2]

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EFFECT OF THE INVENTION The photosensitive lithographic printing plate of the present invention has good sensitivity, high contrast and printing durability, excellent ballpoint pen suitability, cellophane adhesive tape suitability, and accumulation of dust and sludge in the developer. There is also no developer contamination.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinichi Matsubara 1 Sakura-cho, Hino City, Tokyo Konica Co., Ltd. In-house (72) Inventor Katsuko Ota 1000 Kamoshida-cho, Midori-ku, Yokohama, Kanagawa Sanryo Kasei Co., Ltd. In the laboratory

Claims (2)

[Claims] 1. A support made of aluminum or an alloy thereof, which has been subjected to anodizing treatment and then treatment with an aqueous nitrite solution, is provided with (a) an o-quinonediazide compound and (b) triphenylsulfonium trifluoromethanesulfonic acid or A photosensitive lithographic printing plate comprising a photosensitive layer containing bisphenyliodonium trifluoromethanesulfonic acid. 2. The photosensitive lithographic printing plate according to claim 1, wherein the surface of the support is roughened prior to the anodizing treatment.