JPH1090905A - Manufacture of lithographic plate support body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support body with excellent wear resistance and satisfactory water retaining property in which the coloring of the non-image part of a plate after development is minimized by using an electrolyte mainly composed of sulfuric acid, and regulating the concentration of the contained sodium ion to a specified range to perform an anode oxidation. SOLUTION: An electrolyte mainly composed of sulfuric acid is used, and the concentration of the contained sodium ion is regulated to a range of 0-4g/l to perform an anodic oxidation. Namely, the electrolyte is mainly composed of sulfuric acid, but in this case, the electrolysis is preferably performed for 20-250 seconds under conditions of a sulfuric acid concentration of 10-50wt.%, a temperature of 20-50 deg.C, and a current density of 1-20A/dm<2> , and dc is generally used therefor, but ac may be also used. In the electrolyte, 0-15g/l of aluminum ion is preferably contained. Thus, by use of a support body having an anodized coating, a plate having no coloration of non-image part and excellent in wear resistance can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a lithographic printing plate support, and more particularly to a method for producing a lithographic printing plate support characterized by anodizing treatment.

[0002]

2. Description of the Related Art In general, an aluminum support used in a lithographic printing plate is required to have excellent hydrophilicity and water retention, and for this purpose, it is usually required to use a mechanical, chemical or electrochemical method. , So-called "graining". Furthermore,
It is known to anodize the surface to increase the mechanical strength of the grained surface and to obtain additional water retention. Usually, it is used by providing a film by anodic oxidation of about ² to 5 g / m ² .

However, when a printing plate is prepared from a photosensitive lithographic printing plate material having a photosensitive layer provided on an aluminum support having an anodized film, a coloring component in the photosensitive layer remains even in a non-image area, and the residual color is In some cases, it is difficult to discriminate the image from the image part, which may hinder the correction.

For the purpose of solving this problem, Japanese Patent Publication No. 5-32238 discloses that an anodized film is provided with a hydrophilic layer comprising a compound having an amino group and a hydroxyl group and having a molecular weight of 1,000 or less or a salt thereof. Have been described.
According to this, the coloring of the non-image area can be prevented, but the abrasion resistance of the surface of the support decreases.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to solve the problem of coloring of a non-image portion of a lithographic printing plate and to have excellent abrasion resistance. Another object of the present invention is to provide a lithographic printing plate support having good water retention.

[0006]

Means for Solving the Problems The inventor of the present invention carried out anodizing treatment by using an electrolytic solution mainly containing sulfuric acid and adjusting the concentration of sodium ions contained in a range of 0 to 4 g / liter. It has been found that a lithographic printing plate support excellent in abrasion resistance with less coloring of a non-image portion of the printing plate after development can be obtained.

In the anodic oxidation treatment, a porous oxide film (herein referred to as "anodic oxide film") is formed by subjecting a grained (roughened) support to electrolytic treatment in an electrolytic solution as an anode. In the present invention, the electrolytic solution is mainly composed of sulfuric acid. Sulfuric acid concentration is 10-50% by weight, temperature 20-50
20 ° C. and a current density of 1 to 20 A / dm ^2.
The electrolysis is preferably performed for a second, and a direct current is usually used, but an electrolysis may be performed with an alternating current. It is preferable that the electrolyte contains aluminum ions at 0 to 15 g / liter.

[0008] The sodium ion concentration is adjusted by changing the renewal amount of the electrolytic solution or by adding a sodium salt such as sodium sulfate, sodium chloride or sodium nitrate to the electrolytic solution. The method of addition is preferred, and the addition of sodium sulfate is particularly preferred.
The adjustment is made with consideration of the sodium ions that adhere to the aluminum plate and are brought in from the previous process.

The material of the support is usually pure aluminum or silicon, copper, manganese, magnesium, chromium, zinc,
An alloy of aluminum with metals such as lead, bismuth, nickel, titanium, sodium, and iron, and these are collectively referred to as aluminum in this specification.

Prior to roughening, it is preferable to perform a degreasing treatment in order to remove grease, rust, dust and the like on the aluminum surface. Examples of the degreasing treatment include solvent degreasing with trichlene, thinner and the like; emulsion degreasing with an emulsion of kerosene, triethanol and the like. Further, an alkaline aqueous solution such as caustic soda can be used to remove stains and natural oxide films that cannot be removed only by degreasing.

When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, a smut is formed on the surface of the support. Therefore, the substrate is immersed in an acid such as phosphoric acid, nitric acid, chromic acid, or a mixed acid thereof to be desmutted. Is preferred.

The surface roughening method includes a method of mechanically roughening the surface, a method of electrochemically roughening the surface, and a method of roughening the surface with an etching agent composed of an alkali, an acid, or a mixture thereof. There are various methods, and these methods may be combined.

As the mechanical surface roughening method, there are methods such as ball polishing, brush polishing, blast polishing, buff polishing, and honing polishing. Among them, brush polishing and honing polishing are preferable. Alternatively, a method may be employed in which a sheet which has been roughened in advance is adhered to the surface of the support, and the roughened surface pattern is transferred by applying pressure.

In the electrochemical graining method, the surface is electrolytically treated by an alternating current or a direct current in an acidic electrolytic solution containing hydrochloric acid, nitric acid, or the like. For example, Japanese Patent Publication No. 48-28123 and British Patent No. 896,563. And the method described in JP-A-53-67507. The applied voltage is about 1 to 50 V, preferably 2 to 30 V. Also, the quantity of electricity at the anode Q
_a is added to the alternating waveform current such as a larger than the cathode time electricity Q _c, anode during current density 10~150A / dm ^2, preferably about an electrolytic treatment under conditions of 20 to 100 A / dm ^2. Here, the alternating waveform current, a waveform obtained by replacing the positive and negative polarities alternately, as long as Q _a like is greater than Q _c, can be used in any waveform. Q _a and Q _c are 100 to 1000 coulombs / dm ²
Is preferred. The treatment temperature is about 10 to 50 ° C, preferably 15 to 45 ° C, and the concentration of hydrochloric acid or nitric acid is preferably 0.01 to 5% by weight. The electrolyte is preferably nitric acid. If necessary, nitrates, chlorides, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid, and the like can be added to the electrolytic solution.

In the present invention, it is preferable to perform electrochemical surface roughening after mechanically roughening. When two or more surface roughening treatments are combined, it is preferable to use an aqueous acid or alkali solution between the treatments. In that case,
Using a 0.05 to 40% by weight aqueous solution of acid or alkali,
The treatment is performed at a liquid temperature of 40 to 100 ° C. for 5 to 300 seconds.

When the immersion treatment is carried out with an aqueous alkali solution, a smut is formed on the surface of the support. Therefore, it is preferable to immerse the substrate in phosphoric acid, nitric acid, sulfuric acid, chromic acid or the like or a mixed acid thereof to perform the desmutting treatment.

The anodized aluminum support may then be subjected to a sealing treatment. The sealing treatment can be performed by a known method such as a hot water treatment, a boiling water treatment, a steam treatment, a sodium silicate treatment, and a dichromate aqueous solution treatment.

The sealed aluminum support may then be provided with a hydrophilic layer. To form the hydrophilic layer,
The alkali metal silicate described in U.S. Pat. No. 3,181,461, the hydrophilic cellulose described in 1,860,426, the amino acid described in JP-B-6-94234, and the amino acid described in JP-A-6-2436, and salts thereof Amines having a hydroxyl group and salts thereof described in JP-A-62-19 / 1988.
For example, a phosphate described in JP-A-494, a polymer compound containing a monomer unit having a sulfo group described in JP-A-59-101651, or the like can be used.

Further, in order to prevent abrasion of the photosensitive layer when laminated as a photosensitive lithographic printing plate material and to prevent elution of the aluminum component into the developing solution during development, JP-A-50-151136, 57-63293, 60
-73538 and 61-67863, JP-A-6-3
The process of providing a protective layer on the back surface of a support described in No. 5174 or the like can be performed.

A lithographic printing plate material can be prepared by providing a photosensitive layer comprising a known photosensitive composition on a lithographic printing plate support produced according to the present invention.

As the photosensitive layer composition, a positive type composition containing an o-quinonediazide compound as a main component, a diazonium salt, an alkali-soluble diazonium salt, and US Pat.
Nos. 60,863 and 3,060,023, JP-A-59
No.-53836 and the like, a composition comprising an addition-polymerizable unsaturated compound having two or more terminal ethylene groups and a photopolymerization initiator, such as a photopolymerizable compound containing an unsaturated double bond-containing monomer as a main component And cinnamic acid and JP-A-52-98
No. 8, European Patent No. 0410654, JP-A-3-288
No. 853, JP-A-4-25845, and the like, which use a photocrosslinkable compound containing a dimethylmaleimide group or the like as a photosensitive material, are used as negative photosensitive materials. In addition, Japanese Patent Publication No. 37-171
No. 72, No. 38-6691, No. 59-36259,
No. 59-25217, JP-A-56-107246,
No. 56-146145, No. 57-147656, No. 57-161863, No. 58-100862, No. 6
Electrophotographic photosensitive layers described in JP-A Nos. 0-254142 and 62-194257 can also be used.

Among these, as the o-naphthoquinonediazide compound used as the positive photosensitive composition, an ester of 1,2-diazonaphthoquinonesulfonic acid and a pyrogallol-acetone resin described in JP-B-43-28403 is preferable. . U.S. Pat.
No. 3,188,210, esters of 1,2-diazonaphthoquinone-5-sulfonic acid with phenol / formaldehyde resin, JP-A-2-96163, JP-A-2-96165, JP-A-2-96661. 1, 2 described in
-Diazonaphthoquinone-1-sulfonic acid and phenol.
Esters with formaldehyde resin, JP-A-47-53
No. 03, No. 48-13854, No. 48-63802
Nos. 48-63803, 48-96575, 49-38001, JP-B-37-18015, 4
1-111222, 45-9610, 49-17
No. 481, U.S. Pat. Nos. 2,797,213 and 3,4.
53,400, 3,544,323, 3,57
Nos. 3,917, 3,674,495, 3,78
No. 5,825, British Patent Nos. 1,227,602, 1,251,345, 1,267,005, 1,329,888, 1,330,932, German Patent No. Those described in, for example, 854,890 are also preferably used.

Particularly preferred o-naphthoquinonediazide compounds are compounds obtained by reacting a polyhydroxy compound having a molecular weight of 1,000 or less with 1,2-diazonaphthoquinonesulfonic acid.
9402, 58-150948, 58-203
No. 434, No. 59-165053, No. 60-1214
No. 45, No. 60-134235, No. 60-16304
No. 3, No. 61-118744, No. 62-10645
No. 62-10646, No. 62-153950,
Nos. 62-178562 and 64-76047, U.S. Pat. Nos. 3,102,809 and 3,126,281
No. 3,130,047, 3,148,983
Nos. 3,184,310 and 3,188,210
No. 4,639,406 and the like.

In synthesizing these o-naphthoquinonediazide compounds, 1,2-diazonaphthoquinonesulfonic acid chloride is used in an amount of about 0.2 to 1.2 equivalents, preferably about 0.3 equivalents, to the hydroxyl group of the polyhydroxy compound. ~
React with 1.0 equivalent. As the 1,2-diazonaphthoquinonesulfonic acid chloride, 1,2-diazonaphthoquinone-5-sulfonic acid chloride and 1,2-diazonaphthoquinone-4-sulfonic acid chloride can be used. Further, the obtained o-naphthoquinonediazide compound is a mixture of various 1,2-diazonaphthoquinonesulfonic acid ester groups having different positions and introduced amounts, but all of the hydroxyl groups are 1,2-diazonaphthoquinonesulfonic acid esterified compounds. The proportion of the compound thus obtained in the mixture (content of the completely esterified compound) is preferably 5 mol% or more, more preferably 2 mol% or more.
0 to 99 mol%. The amount of these positive photosensitive materials in the photosensitive composition is about 10 to 50% by weight, and more preferably 15 to 50% by weight.
~ 40% by weight is preferred.

Although the o-quinonediazide compound alone can constitute the photosensitive layer, it is preferable to use a resin which is soluble in alkaline water as a binder. Specifically, a phenol formaldehyde resin, o
-, M- and p-cresol formaldehyde resins, m
-/ P- mixed cresol formaldehyde resin, phenol / cresol (o-, m-, p-, m- / p- and o- / m- mixed), novolak resin such as mixed formaldehyde resin, and phenol-modified Examples thereof include xylene resins, polyhydroxystyrene, polyhalogenated hydroxystyrene, and phenolic hydroxyl group-containing acrylic resins described in JP-A-51-34711.

Other suitable binders include copolymers having the following monomers as constituent units and having a molecular weight of 10,000 to 200,000.

(1) Acrylamides, methacrylamides, acrylates, methacrylates, hydroxystyrenes having an aromatic hydroxyl group;
(4-hydroxyphenyl) acrylamide, N- (4
-Hydroxyphenyl) methacrylamide, o-, m-
Or p-hydroxystyrene, o-, m- or p-hydroxyphenyl acrylate or methacrylate; (2) acrylates and methacrylates having an aliphatic hydroxyl group; 2-hydroxyethyl acrylate or methacrylate; (3) acryl Unsaturated carboxylic acids such as acid, methacrylic acid, maleic anhydride and methaconic acid (4) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, cyclohexyl acrylate, acrylic acid Octyl, phenyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, 4-acrylic acid
(Substituted) acrylates such as hydroxybutyl, glycidyl acrylate, N-dimethylaminoethyl acrylate, etc. (5) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate (Substituted) methacrylates such as octyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-chloroethyl methacrylate, 4-hydroxybutyl methacrylate, glycidyl methacrylate, N-dimethylaminoethyl methacrylate, (6) acrylamide, Methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-ethylacrylamide, N-ethylmethacrylamide, N-hexyl Acrylamide, N- hexyl methacrylamide, N- cyclohexyl acrylamide,
N-cyclohexylmethacrylamide, N-hydroxyethylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N-phenylmethacrylamide, N-benzylacrylamide, N-benzylmethacrylamide, N-nitrophenylacrylamide, N-nitrophenyl Methacrylamide, N-ethyl-N-phenylacrylamide, N-ethyl-N-
Acrylamide or methacrylamide such as phenyl methacrylamide; (7) vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, and phenyl vinyl ether; (8) vinyl acetate, vinyl chloroacetate; Vinyl esters such as vinyl butyrate and vinyl benzoate (9) Styrenes such as styrene, methyl styrene and chloromethyl styrene (10) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl vinyl ketone ( 11) Olefins such as ethylene, propylene, isobutylene, butadiene, isoprene, etc. (12) N-vinylpyrrolidone, N-vinyl Rubazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile, etc. (13) N- (o-aminosulfonylphenyl) acrylamide, N- (m-aminosulfonylphenyl) acrylamide, N- (p-aminosulfonylphenyl) acrylamide, N Acrylamides such as-[1- (3-aminosulfonyl) naphthyl] acrylamide, N- (2-aminosulfonylethyl) acrylamide;
(O-aminosulfonylphenyl) methacrylamide,
N- (m-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) methacrylamide, N- [1- (3-aminosulfonyl) naphthyl] methacrylamide, N- (2-aminosulfonylethyl) methacryl Methacrylamides such as amides; o-
Unsaturated sulfonamides such as acrylates such as aminosulfonylphenyl acrylate, m-aminosulfonylphenyl acrylate, p-aminosulfonylphenyl acrylate and 1- (3-aminosulfonylphenylnaphthyl) acrylate; o-aminosulfonylphenyl methacrylate And unsaturated sulphonamides such as methacrylic acid esters such as m-aminosulfonylphenyl methacrylate, p-aminosulfonylphenyl methacrylate, 1- (3-aminosulfonylphenylnaphthyl) methacrylate.

Further, a copolymer obtained by copolymerizing the above-mentioned monomer and modified with glycidyl acrylate, glycidyl methacrylate or the like is also included.

These copolymers preferably contain the unsaturated carboxylic acids listed in (3), and the copolymer preferably has an acid value of 0 to 10 meq / g, more preferably 0.2 to 10 meq / g.
It is 5.0 meq / g. The preferred molecular weight of these copolymers is 10,000 to 100,000. If necessary, a polyvinyl butyral resin, a polyurethane resin, a polyamide resin, or an epoxy resin may be added to these copolymers.

The binder is used in an amount of not more than 80% by weight of the photosensitive composition.

Further, as described in U.S. Pat. No. 4,123,279, condensation of formaldehyde with a phenol having an alkyl group having 3 to 8 carbon atoms as a substituent, such as t-butylphenol formaldehyde resin and octylphenol formaldehyde resin. It is preferable to use a combination of these substances because the oil sensitivity of the image is improved. It is preferable to add cyclic acid anhydrides, phenols, and organic acids to the photosensitive composition in order to increase sensitivity.

As the cyclic anhydride, US Pat.
Phthalic anhydride described in Patent 5,128, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-oxy - [delta ⁴ - tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic acid anhydride, chlorosulfonic maleic anhydride, α-phenyl maleic anhydride, succinic anhydride, pyromellitic anhydride and the like can be used.

As phenols, bisphenol A, p-nitrophenol, p-ethoxyphenol,
2,4,4'-trihydroxybenzophenone, 2,
3,4-trihydroxybenzophenone, 4-hydroxybenzophenone, 4,4 ', 4 "-trihydroxy-
Triphenylmethane, 4,4 ', 3 ", 4"-tetrahydroxy-3,5,3',5'-tetramethyltriphenylmethane and the like.

As the organic acids, JP-A-60-8894
2, sulfonic acids, sulfinic acids, alkyl sulfates, phosphonic acids described in JP-A-2-96755 and the like;
Phosphoric acid esters and carboxylic acids and the like, specifically, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethyl sulfate, phenylphosphonic acid, phenylphosphinic acid, phenyl phosphate, phenyl phosphate, diphenyl phosphate, Benzoic acid, isophthalic acid, adipic acid, p-toluic acid, 3,4-dimethoxybenzoic acid,
Phthalic acid, terephthalic acid, 1,4-cyclohexene-
Examples thereof include 2,2-dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid, and ascorbic acid.

The proportion of these cyclic acid anhydrides, phenols and organic acids in the photosensitive composition is 0.05 to 15%.
% By weight, preferably 0.1 to 5% by weight.

In order to increase the processing stability (development latitude) irrespective of the development conditions, the photosensitive composition contains
Nonionic surfactants described in JP-A-62-251740, JP-A-59-121044, JP-A-4-131
An amphoteric surfactant described in No. 49 can be added. Specific examples of the nonionic surfactant include sorbitan tristearate, sorbitan monopalmitate, sorbitan triolate, monoglyceride stearate,
Examples thereof include polyoxyethylene sorbitan monooleate and polyoxyethylene nonylphenyl ether. Specific examples of the amphoteric surfactant include alkyldi (aminoethyl) glycine, alkylpolyaminoethylglycine hydrochloride, 2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine and N-tetradecyl-N, N- Betaine type (for example, Daiichi Kogyo Co., Ltd.)
Manufactured by Amogen K), alkyl imidazoline (manufactured by Sanyo Chemical Co., Ltd .: Levon 15) and the like. The ratio of these surfactants in the photosensitive composition is 0.05 to 15%.
% By weight, and more preferably 0.1 to 5% by weight.

Further, a printing-out agent for obtaining a visible image immediately after exposure, and a dye or pigment as an image coloring agent can be added to the photosensitive composition. As a baking agent,
Combinations of compounds that release acid upon exposure (photoacid releasing agents) and organic dyes capable of forming salts, specifically, o-type compounds described in JP-A-50-36209 and JP-A-53-8128.
Combinations of naphthoquinonediazide-4-sulfonic acid halogenides with salt-forming organic dyes and JP-A-53-362
No. 23, No. 54-74728, No. 60-3626,
The combinations of the trihalomethyl compounds and the salt-forming organic dyes described in JP-A-61-143748, JP-A-61-151644, and JP-A-63-58440 can be mentioned as representatives. Trihalomethyl compounds include oxazole-based compounds and triazine-based compounds, both of which are excellent in stability over time and give clear print-out images.

As the colorant for the image, other dyes can be used in addition to the above-mentioned salt-forming organic dyes. Suitable dyes, including salt-forming organic dyes, include oil-soluble dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS,
Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-505 (all manufactured by Orient Chemical Industry Co., Ltd.), Victoria Pure Blue, Crystal Violet (CI42555), Methyl Violet (CI42535), Ethyl Violet, Rhodamine B (CI45170B), malachite green (CI42000), methylene blue (CI5201)
5) and the like. Also, JP-A-62-293
The dye described in No. 247 is particularly preferred.

The photosensitive composition dissolves each of the above components,
For example, it is dissolved and dispersed in a solvent as described in JP-A-62-251739 at a solid content of 2 to 50% by weight,
It is coated on a support at a weight of 0.3 to 4.0 g / m ² after drying and dried. In the photosensitive composition, a surfactant for improving the coating surface quality, for example, JP-A-62-17
No. 0950 can be added. A preferable addition amount is 0.0% of the entire photosensitive composition.
0.01 to 1.0% by weight, and more preferably 0.005 to 0.5%
% By weight.

Next, examples of the negative photosensitive composition include those containing a photosensitive diazo compound, photopolymerizable ones, and photocrosslinkable ones. As the photosensitive diazo compound,
A diazo resin obtained by condensing an aromatic diazonium salt with an organic condensing agent containing a reactive carbonyl group, particularly an aldehyde such as formaldehyde or acetaldehyde or an acetal in an acidic catalyst is preferably used, and a typical example is p-diazodiphenylamine. And formaldehyde. The synthesis of these diazo resins is described in U.S. Pat.
No. 78,498, No. 3,050,502, No. 3,31
Nos. 1,605 and 3,277,074. In addition, as a photosensitive diazo compound,
No. 48001 is preferably used a co-condensed diazo compound of an aromatic diazonium salt and a substituted aromatic compound not containing a diazonium group, particularly an aromatic substituted with an alkali-soluble group such as a carboxyl group or a hydroxyl group. Co-condensed diazo compounds with compounds are preferred. Further, Japanese Patent Laid-Open No. 4-1
No. 8559, No. 4-172353, No. 4-19036
A photosensitive diazo compound obtained by condensing an aromatic diazonium salt with the reactive carbonyl compound having an alkali-soluble group described in No. 1 is also preferably used. As a counter anion of these diazonium salts, there are diazo resins using mineral acids such as hydrochloric acid, hydrobromic acid, sulfuric acid and phosphoric acid or inorganic anions such as double salts with zinc chloride, but are substantially water-insoluble and organic solvents. Soluble diazo resins are particularly preferred. Such preferred diazo resins are disclosed in JP-B-47-1167, U.S. Pat. No. 3,300,3.
No. 09 is described in detail.

Further, JP-A-54-98613 and JP-A-56-98613 describe the same.
A diazo resin having a counter anion of a halogenated Lewis acid such as tetrafluoroboric acid and hexafluorophosphoric acid and a perhalic acid such as perchloric acid and periodic acid described in No. 121031 is preferably used. Also, JP-A-58-209733
And diazo resins having a long chain alkyl group-containing sulfonic acid as a counter anion described in JP-A Nos. 62-175731 and 63-262643 are also preferably used. The photosensitive diazo compound is contained in the photosensitive layer in an amount of about 5 to 50% by weight, preferably 8 to 20% by weight.

The photosensitive diazo compound is preferably used in combination with a lipophilic polymer compound soluble or swellable in alkaline water as a binder, and is used in the above-mentioned positive photosensitive composition (1) to (1). There can be mentioned a copolymer having a molecular weight of usually 10,000 to 200,000 having the monomer of 13) as a constitutional unit, and further a polymer compound copolymerized with the monomer of the following (14) and (15) as a constitutional unit. Can be used.

(14) Maleimide, N-acryloylacrylamide, N-acetylacrylamide, N-propionylacrylamide, N- (p-chlorobenzoyl) acrylamide, N-acetylacrylamide, N
-Acryloyl methacrylamide, N-acetyl methacrylamide, N-propionyl methacrylamide, N-
Unsaturated imides such as (p-chlorobenzoyl) methacrylamide (15) N- [2- (acryloyloxy) -ethyl]
Unsaturated monomers having a crosslinkable group in the side chain, such as -2,3-dimethylmaleimide, N- [6- (methacryloyloxy) -hexyl] -2,3-dimethylmaleimide and vinylcinnamate;

Further, monomers copolymerizable with these may be copolymerized, or the resulting copolymer may be modified with glycidyl acrylate or glycidyl methacrylate. These copolymers preferably contain the above-mentioned unsaturated carboxylic acid (3), in which case the acid value is about 0 to 10 meq / g, preferably 0.2 to 5 meq / g.
0 meq / g. The molecular weight of the copolymer is preferably 10,000 to 100,000.

If necessary, a polyvinyl butyral resin, a polyurethane resin, a polyamide resin, or an epoxy resin may be added to these copolymers. Novolak resins, phenol-modified xylene resins, polyhydroxystyrenes, polyhalogenated hydroxystyrenes, and phenolic hydroxyl-containing alkali-soluble resins described in JP-A-51-43711 can also be used. The binder is usually contained in the solid content of the entire photosensitive composition in the range of 40 to 95% by weight.

In the photosensitive composition, a sensitizing agent (half-esterified product of a styrene-maleic anhydride copolymer with an alcohol described in JP-A No. 55-527) for improving the oil sensitivity of an image, Novolak resins, 50% fatty acid esters of p-hydroxystyrene, etc.). Furthermore, plasticizers for imparting flexibility and abrasion resistance of the coating film (butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, Trioctyl phosphate, tetrahydrofurfuryl oleate, oligomers and polymers of acrylic acid or methacrylic acid, particularly preferably tricresyl phosphate) are added. In the photosensitive composition, phosphoric acid, phosphorous acid, citric acid, oxalic acid, dipicophosphoric acid, benzenesulfonic acid, naphthalenesulfonic acid, sulfosalicylic acid, 4-methoxy-2-hydroxybenzophenone are used in order to extend the stability over time. -5-sulfonic acid, tartaric acid and the like are added.

In the photosensitive composition, a printing-out agent for obtaining a visible image immediately after exposure, and a dye such as a dye or a pigment as an image coloring agent can be added. As the dye, those which change color by reacting with a free radical or an acid are preferable. Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.), Oil Yellow # 101, Oil Yellow #
103, oil pink # 312, oil red, oil green BG, oil blue BOS, oil blue # 6
03, oil black BY, oil black BS, oil black T-505 (all manufactured by Orient Chemical Co., Ltd.), patent pure blue (manufactured by Sumitomo Sangoku Chemical Co., Ltd.), crystal violet (CI42555), methyl violet (CI42535), Ethyl violet, rhodamine B (CI145170B), malachite green (CI42000), methylene blue (CI
52015), brilliant blue, methyl green,
Erythricin B, basic fuchsin, m-cresol purple, auramine, triphenylmethane series represented by 4-p-diethylaminophenyliminaphthoquinone, cyano-p-diethylaminophenylacetanilide, diphenylmethane series, oxazine series, xanthene series, iminonaphthoquinone Examples of the color, azomethine-based or anthraquinone-based dyes changing from colored to colorless or different colored tones.

On the other hand, examples of the color changing agent which changes from colorless to colored include leuco dye, triphenylamine, diphenylamine, o-chloroaniline, 1,2,3-triphenylguanidine, naphthylamine, diaminodiphenylmethane, p, p '. -Bis-dimethylaminodiphenylamine, 1,2-dianilinoethylene, p, p ', p "-
Tris-dimethylaminotriphenylmethane, p, p '
-Bis-dimethylaminodiphenylmethylimine, p,
p ', p "-triamino-o-methyltriphenylmethane, p, p'-bis-dimethylaminodiphenyl-4-
Primary or secondary arylamine dyes represented by anilinonaphthylmethane and p, p ', p "-triaminotriphenylmethane are preferable. Triphenylmethane dyes and diphenylmethane dyes are preferred. More preferred are triphenylmethane dyes, especially Victoria Pure Blue BOH, which are contained in the photosensitive composition at about 0.5 to 10% by weight, preferably 1 to 5% by weight.

In the photosensitive composition, cyclic acid anhydrides, phenols, organic acids and higher alcohols can be added in order to enhance developability. The photosensitive composition dissolves each of the above components, for example, as described in JP-A-62-251739.
In a solvent as described in (1), at a solid content of 2 to 50% by weight, and dissolved and dispersed, and 0.3 to 4.
It is coated on a support at 0 g / m ² and dried. A surfactant can be added to the photosensitive composition as in the case of the positive type composition.

A mat layer is provided on the surface of the photosensitive layer in order to shorten the evacuation time in the close contact exposure using a vacuum printing frame and to prevent printing blur.
No. 05, Japanese Patent Publication No. 57-6582, No. 61-28986
No. 62-62), a method of providing a mat layer described in
No. 337, for example, a method of thermally fusing a solid powder. The average particle size of the matting agent is 100 μm or less, the average height of the matting layer is 10 μm or less, further 2 to 8 μm, and the coating weight of the matting layer is 5 to 200 mg / m ² , further 20 to 15 μm.
0 mg / m ² is preferred.

[0051]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 Supports 1 to 3 were prepared in the following procedure.

<< Preparation of Support 1 >> The surface of an aluminum plate of JIS 1050 was roughened with a rotating nylon brush using a Pumice-water suspension as an abrasive. At this time, the surface roughness (center line average roughness) was 0.5 μm. After washing with water, 7
The aluminum surface was immersed in a 10% aqueous sodium hydroxide solution maintained at 0 ° C., and etched so that the amount of aluminum dissolved on the aluminum surface was 5 g / m ² . After washing with water, it was immersed in a 30% aqueous nitric acid solution for 1 minute, and anodic voltage was 23 V in a 0.7% aqueous nitric acid solution.
A rectangular wave alternating waveform having a cathode voltage of 12 V (JP-A-56-47)
No. 041), electrolytic surface roughening was carried out at an anode electricity amount of 160 coulomb / dm ² , and after washing with water, the amount of aluminum surface dissolved with a 10% aqueous sodium hydroxide solution was 2 g / It was etched so as to obtain m ² , washed with water, neutralized and washed with 20% sulfuric acid, and further washed with water.

<< Preparation of Support 2 >> The surface of an aluminum plate of JIS 1050 was immersed in a 10% aqueous sodium hydroxide solution.
After immersion for 0 seconds to perform a degreasing treatment, it was washed with water, neutralized with 10% sulfuric acid, and further washed with water. Then, in an aqueous 1.0% nitric acid solution, electrolytic surface roughening is performed under the conditions of a sine wave alternating current at a temperature of 30 ° C. and a current density of 60 A / dm ² under the condition that the quantity of electricity at the anode is 400 coulombs / dm ^2. The aluminum surface was etched with a 10% aqueous sodium hydroxide solution so that the amount of aluminum dissolved was 2 g / m ² , washed with 20% sulfuric acid for neutralization, and further washed with water.

<< Preparation of Support 3 >> The preparation of the support 2 was carried out in the same manner as the preparation of the support 2, except that the electrolytic surface roughening with a 1.0% aqueous nitric acid solution was changed to the electrolytic surface roughening with a 1.0% hydrochloric acid aqueous solution. Support 3 was obtained.

Each of the obtained supports was subjected to anodizing treatment in a 17% sulfuric acid aqueous solution at 30 ° C. at a current density of 2 A / dm ² for 100 seconds. At this time, the sodium ion concentration in the aqueous sulfuric acid solution was changed to 0 g / L, 1 g / L, 2 g / L, 4 g / L, 6 g / L, and 8 g / L by adding sodium sulfate.

A photosensitive composition coating solution having the following composition was applied to each support using a wire bar, and the coating weight after drying was 1.
The composition was applied so as to be 8 g / m ² and dried at 80 ° C. to obtain a photosensitive lithographic printing plate material.

<< Photosensitive Composition >> Esterification reaction product of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 2,3,4-trihydroxybenzophenone 0.5 g phenol formaldehyde resin (weight average molecular weight: 2300) 2.0 g 2- (p-butoxyphenyl) -4,6-bis (trichloromethyl) -S-triazine 0.02 g naphthoquinone-1,2-diazide-4-sulfonic acid chloride 0.03 g crystal Violet 0.01 g Oil Blue # 603 (manufactured by Orient Chemical Industry Co., Ltd.) 0.015 g Ethylene dichloride 18 g 2-methoxyethyl acetate 12 g Each of the resulting photosensitive lithographic printing plate materials was placed in a vacuum furnace. A 3kW metal halide lamp from a distance of 1m through a transparent positive film After 50 seconds exposure had a molar ratio of SiO ₂ / Na ₂ O and developed with 5.26% aqueous solution of sodium silicate 1.74 (pH 12.7).
Subsequently, the film was sufficiently washed with water, and the remaining color and abrasion resistance of the non-image area were evaluated.

<< Evaluation of Remaining Color in Non-Image Area >> The difference (ΔD) between the reflection optical density of the non-image area and the reflection optical density of the surface of the support immediately before the application of the photosensitive composition was calculated.

<< Evaluation of Abrasion Resistance of Non-Image Area >> Abrasion tester manufactured by Suga Test Instruments Co., Ltd .: The wear of the non-image area after reciprocating 400 times with alumina abrasive paper using NUS-ISO-1 type was determined as follows. Evaluation was based on criteria.

◎: not worn ○: hardly worn △: slightly worn ×: worn

The results are shown below.

Support Na ⁺ concentration Remaining color Abrasion resistance Remarks (g / liter) 10 0.01 ◎ The present invention 11 0.01 ◎ The present invention 310.02 ○ The present invention 2 0.01 ○ Present invention 22 0.02 △ Present invention 14 0.01 △ Present invention 16 0.08 × comparison 38 0.12 × comparison

[0064]

According to the present invention, a lithographic printing plate excellent in abrasion resistance without coloring of a non-image area can be obtained by using a support provided with an anodized film.

Claims (1)

[Claims] 1. A method for producing a lithographic printing plate support, wherein anodizing treatment is performed using an electrolytic solution mainly containing sulfuric acid and having a sodium ion concentration of 0 to 4 g / liter.