JPH06171256A - Support for planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain the We support suitable for the support for a printing plate having independent pits separated one by one and having dense and uniform unevenness by forming a large number of pressed recessed parts having no directionality and having an average diameter of a specific value or less on the surface of an aluminum plate. CONSTITUTION:The surface of an aluminum plate as a support for a planographic printing plate is roughened in order to improve not only the close adhesion of the photosensitive layer with the aluminum plate but also the water retention of the non-image part of the planographic printing plate produced using the aluminum plate. In this case, a large number of pressed recessed parts with an average diameter of 6mum or less having no directionality are provided on the surface of the aluminum plate at the time of surface roughening. By this constitution, the support for the planographic printing plate having dense and uniform unevenness having pits independently separated one by one is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing plate support, and more particularly to a lithographic printing plate support comprising a roughened aluminum plate suitable for offset printing plates.

[0002]

2. Description of the Related Art Conventionally, an aluminum plate has been widely used as a support for a lithographic printing plate, but it has good adhesion to a photosensitive layer provided thereon, and a lithographic printing plate produced by using the same. The surface of the aluminum plate is usually roughened for the purpose of improving the water retention in the non-image area of the plate (the area that receives dampening water used during printing and repels oil-based ink). is there. This roughening treatment is called so-called graining, and is an indispensable step in the preparation of the lithographic printing plate support, and is a work that requires a considerable degree of skill. This graining is roughly classified into mechanical graining methods such as ball grain, wire grain and brush grain, and electrochemical graining methods.

In the case of ball grains, the ball material,
There are many factors that require skill, such as the type of polishing agent and the adjustment of water content during polishing, and it is not possible to perform the work continuously, and it is necessary to finish each one. Also, wire grain is
The resulting grain is uneven. On the other hand, brush grain is an improved version of these methods, and it is suitable for mass production because it has a uniform grain and can be continuously treated.

However, with the above-mentioned mechanical method, it is difficult to obtain sufficient performance because a fine recess cannot be formed as a printing plate support. Generally, it is said that the larger the surface roughness is, the better the water retention (that is, water retention) is. Therefore, when preparing a lithographic printing plate for the purpose of improving the water retention and making printing easier, It is said that the surface shape is preferably as dense and uniform as possible. As a method for obtaining such a preferable surface shape, an electrochemical roughening method has been attracting attention. According to the electrochemical roughening method, it is possible to easily form irregularities having an average diameter of 1 to 6 μm.

[0005]

In the case of the electrochemical method, if the various conditions such as the composition of the electrolytic solution, the temperature, and the electrolysis condition are kept constant, a dense and uniform honeycomb-like unevenness is formed. Although it is possible to obtain an aluminum plate which is easy to make and has a certain roughened surface, however, the range of electrolysis conditions thereof is very narrow, and therefore, it is not possible to electrolyze by adjusting so as to always keep it within such a range. , Extremely difficult.

An object of the present invention is to solve the above problems and provide a lithographic printing plate support suitable as a printing plate support in which each pit is separated and independent and has fine and uniform unevenness. .

[0007]

MEANS TO SOLVE THE PROBLEMS The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, have found that depressions with an average diameter of 6 μm or less can be stably formed. The present invention has been reached. That is, the above object of the present invention is to provide a support for a non-directional lithographic printing plate characterized in that the surface of an aluminum plate has a large number of press recesses having a non-directional average diameter of 6 μm or less.
Achieved by

The recesses of the aluminum plate of the lithographic printing plate support of the present invention are formed by passing the aluminum plate through a roll which has been embossed by shotplast, engraving, laser processing, pattern etching, or the like to transfer the unevenness of the rolling roller. Alternatively, a paper or a plastic sheet coated with an abrasive, glass beads or the like may be superposed on an aluminum plate, rolled, and transferred.

The density of non-directional recesses having an average diameter of 6 μm or less is preferably 10,000 / mm ² or more. The average surface roughness of the rough surface formed by pressing is 0.3 to 2.
0 μm is preferable. The rough surface of the present invention includes not only one surface of the aluminum plate but also one having both surfaces. The production method of the grain obtained in the present invention is simple, and the auxiliary equipment can be made much smaller than the brush grain and the electrolytic grain.

The aluminum plate of the present invention having a press recess having an average diameter of 6 μm or less, which has no directionality on the surface, can be used as it is as a support for a lithographic printing plate, and is further used in an alkaline or acidic aqueous solution. Chemical etching treatment, electrochemical roughening treatment by direct current or alternating current in an aqueous solution containing nitric acid or hydrochloric acid, mild etching treatment in alkaline or acidic aqueous solution, anode in sulfuric acid or phosphoric acid aqueous solution Oxidation treatment, hydrophilic treatment in a silicic acid aqueous solution, and the like are more preferable as the lithographic printing plate support. These treatments after pressing can be performed under the conditions conventionally adopted in this field.

The aluminum plate used in the present invention includes pure aluminum and aluminum alloy.
Various materials can be used as the aluminum alloy, for example, alloys of silicon, copper, manganese, magnesium, chromium, zinc, lead, nickel, bismuth, etc., and aluminum alloys are used. There are various kinds of aluminum alloys, but as a plate material for offset printing, for example, Japanese Patent Publication No.
In Japanese Patent No. 6635, the Fe and Si components are limited and the intermetallic compound is specified. In addition, Japanese Examined Japanese Patent Publication 55-28874
In the publication, cold rolling rate and intermediate annealing are performed to limit the voltage applying method for electrolytic surface roughening. Japanese Patent Publication Sho 62-4130
4, Japanese Patent Publication 1-46577, Japanese Patent Publication 1-46578,
Japanese Patent Publication 1-47545, Japanese Patent Publication 1-35910, Japanese Patent Publication No. 63-60823, Japanese Publication No. 63-60824, Japanese Patent Publication No. 4
-13417, Japanese Patent Publication No. 4-19290, Japanese Patent Publication No. 4-19
291, Japanese Patent Publication No. 4-19293, Japanese Patent Publication No. 62-5054
0, JP-A-61-272357, JP-A-62-1406
0, JP-A-61-1201747, JP-A-63-1432
34, JP-A-63-143235, and JP-A-63-255.
338, JP-A-1-283350, EP272.
528, U.S. Pat. Nos. 4,902,353, 4,818,300,
EP394816, US Pat. No. 5,019,188, West German Patent 3232810, US Pat. No. 4,435,230, EP2.
39995, US Pat. No. 4,822,715, West German Patent 3
507402, U.S. Pat. No. 4,715,903, West German Patent 3507402, EP 289844, U.S. Pat.
722, 4945004, West German Patent 371405.
9, US Pat. Nos. 4,468,083, 4,861,396, EP
Not only the aluminum alloys shown in the respective specifications of 158941, but also general alloys are included. As a method of manufacturing a plate material, a method using hot rolling and a method of performing continuous casting have been recently applied. For example,
In East German Patent No. 252799, a plate material manufactured by a twin roll method is introduced. EP22373
7, U.S. Pat. Nos. 4,802,935 and 4,800,950,
It has been filed in a form in which trace alloy components are limited. EP41
5238 proposes continuous casting and continuous casting + hot rolling.

In the present invention, such an aluminum plate can be subjected to various surface treatments, transfers, etc. to obtain a printing base plate having uniform unevenness, and a photosensitive layer such as a diazo compound is provided on the printing base plate. Thus, an excellent photosensitive lithographic printing plate can be obtained. In any case, it is necessary to select an appropriate material.

Next, the processing conditions for these aluminum plates will be shown. Prior to the present invention (by transfer), pretreatment may be performed to remove rolling oil on the aluminum surface and to expose a clean aluminum surface. In the former case, a solvent such as trichlene and a surfactant are used. In the latter case, a method using an alkali etching agent such as sodium hydroxide or potassium hydroxide is widely used. In Japanese Patent Application Laid-Open No. 2-026793,
Degreasing treatment is described. For example, as a solvent degreasing method, a method using a petroleum solvent such as gasoline, kerosene, benzine, solvent naphtha, and normal hexane, a chlorine-based solvent such as tolchlorethylene, methylene chloride, perchlorethylene, and 1-1-1 trichloroethane. There is a method of using a solvent. As the alkali degreasing method, a method using sodium hydroxide such as sodium hydroxide, sodium carbonate, sodium bicarbonate, and sodium sulfate, silicic acid such as sodium orthosilicate, sodium metasilicate, sodium silicate No. 2, sodium silicate No. 3, and the like. There are a method using an aqueous solution of a salt, a method using an aqueous solution of a phosphate such as sodium monophosphate, sodium triphosphate, sodium diphosphate, sodium tripolyphosphate, sodium pyrophosphate, and sodium hexametaphosphate. When the alkaline degreasing method is used, the aluminum surface may be dissolved depending on the treatment time and the treatment temperature. Therefore, it is necessary to prevent the dissolution phenomenon from occurring during the degreasing treatment. As the degreasing treatment with a surfactant, an aqueous solution of an anionic surfactant, a cationic surfactant, a nonionic surfactant, and an amphoteric surfactant is used, and various commercial products can be used. As a degreasing method, a dipping method,
It is possible to use a spraying method, a method of rubbing a liquid into a cloth, etc. In addition, ultrasonic waves may be used for the dipping or spraying method.

The recess of the aluminum plate of the present invention is formed by transfer, the content of which is as described above.

After the unevenness is formed by the transfer as described above, the aluminum surface is chemically treated with an acid or alkali for the purpose of smoothing and uniformizing the aluminum plate, if necessary. Particularly, in the case of performing electrochemical surface roughening, the surface roughening becomes non-uniform when the surface is continuously transferred after the transfer.
Specific examples of the acid and alkali to be treated in this way include a method using a soda salt such as phosphoric acid, sulfuric acid, hydrochloric acid, nitric acid, sodium hydroxide, sodium carbonate, sodium bicarbonate, sodium sulfate, sodium orthosilicate, sodium metasilicate. , A method using an aqueous solution of a silicate such as sodium disilicate, sodium trisilicate, etc., sodium monophosphate, sodium phosphate tribasic, sodium phosphate dibasic, sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, etc. There is a method using an aqueous solution of phosphate. The treatment conditions include a concentration of 0.01% to 50%,
The temperature is appropriately selected from 20 ° C to 90 ° C and time of 5 seconds to 5 minutes. The etching amount is appropriately selected depending on the aluminum material and the required quality. Japanese Unexamined Patent Publication Nos. 54-65607 and 55-125299 propose a pretreatment for electrochemical graining. JP-A-63-235500
No. 63-307990, JP-A-11-12738
8, JP-A-1-160690, JP-A-1-13678
9, JP-A-1-136788, JP-A-1-17849
7, JP-A-1-308689, JP-A-3-12689
1, JP-A-3-126900, JP-A-3-173800
Although various publications and the like include various pretreatments, the present invention
It is not limited to these. However, when the aluminum surface is chemically treated with an acid / alkali aqueous solution in this manner, an insoluble residue portion, that is, smut, is generated on the surface. This smut contains phosphoric acid, nitric acid, sulfuric acid,
It can be removed with chromic acid or a mixture thereof. In the present invention, the aluminum surface subjected to the electrochemical graining treatment is preferably a clean surface without smut. However, when the electrolytic solution is an acid and has a desmutting effect, this can be omitted.

If necessary, the aluminum plate thus treated is subjected to electrochemical graining. The electrochemical grain method is described in JP-B-48-28123 and British Patent 896563. The above-mentioned electrolytic graining conventionally uses an alternating current having a sinusoidal waveform, but may be performed using a special waveform as described in JP-A-52-58602. Further, JP-A-55-158298 and JP-A-56-2
8898, JP-A-52-58602, JP-A-52-15
2302, JP-A-54-85802, JP-A-60-19
0392, JP-A-58-120531, JP-A-60-1
47394, JP-A-63-176187, JP-A-1-5.
859, JP-A-1-280590, JP-A-1-1184.
89, JP-A-1-148592, JP-A-1-17849.
6, JP-A-1-188395, JP-A-1-15479
7, JP-A-2-235794, JP-A-3-26010
0, JP-A-3-253600, JP-A-4-72099,
The methods disclosed in JP-A-4-72098, JP-A-3-267400, JP-A-1-141094 and the like can also be applied.

As the frequency, other than the above, those proposed in the electrolytic capacitor can be used. For example,
U.S. Pat. Nos. 4,276,129 and 4,676,879. As the electrolytic solution, nitric acid, hydrochloric acid, etc., in addition to the above-mentioned ones, U.S. Pat.
19, same 4618405, same 462628, same 4600
482, same 4566960, same 4566958, same 45
Electrolyte solutions such as 66959, 4416972, 4374710, 4336113, and 4184932 can also be used. Various proposals have been made for an electrolytic cell and a power source, but U.S. Pat.
6-123400, JP 57-59770, JP 5
3-12738, JP-A-53-32821, JP-A-53
-32822, JP-A-53-32823, JP-A-55-
122896, JP-A-55-132884, JP-A-62.
-127500, JP-A-1-52100, JP-A-1-52098, JP-A-60-67700, JP-A-1
-230800, JP-A-3-257199, and the like. In addition to the patents mentioned above, various proposals have been made. For example, JP-A-52-58602 and JP-A-52-1
52302, JP-A-53-1238, and JP-A-53-1
2739, JP-A-53-32821, and JP-A-53-32.
822, JP-A-53-32833, and JP-A-53-328.
24, JP-A-53-32825, JP-A-54-8580
2, JP-A-55-122896, JP-A-55-1328
84, Japanese Patent Publication 48-28123, Japanese Patent Publication 51-708
1, JP-A-52-133838, JP-A-52-1338
40, JP-A-52-133844, JP-A-52-133
845, JP-A-53-149135, JP-A-54-14
Of course, each of the 6234 publications and the like can also be applied.

The sample thus obtained is treated with an alkali or an acid, if necessary. JP-A-56
Alkali treatment as described in JP-A-51388,
Desmutting treatment is performed with sulfuric acid as described in JP-A-3-12739. Further, as in JP-A-53-115302, phosphoric acid treatment, JP-A-60-8091, JP-A-63-176188, JP-A-1-38291, JP-A-1-127389, JP-A-1-188699. JP-A-3-177600, JP-A-3-12891, JP-A-1-
Each of the 191100 publications and the like can also be used.

It is preferable to form an anodized film on the surface of the aluminum support thus obtained. As the electrolytic solution, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, or the like, or an aqueous solution or a non-aqueous solution in which two or more kinds of these are combined is used.
An anodized film can be formed. The treatment conditions for anodizing vary variously depending on the electrolytic solution used, so it cannot be said unequivocally, but generally the concentration of the electrolytic solution is 1
~ 80% by weight, liquid temperature 5-70 ° C, current density 0.5-60
A / dm ² , voltage 1 to 100 V, electrolysis time 15 seconds to 50
Minutes are appropriate. As an electrolysis device, Japanese Patent Laid-Open No. 48-26
638, JP-A-47-18739, JP-B-58-245.
The submerged power supply method is introduced in each of the 17 publications. Further, JP-A-54-81133, JP-A-57-4789
4, JP-A-57-51289, JP-A-57-5129
0, JP-A-57-54300, JP-A-57-5789
6, JP-A-58-107498, JP-A-60-2002
56, JP-A-62-136596, JP-A-63-176
494, JP-A-4-176899, and JP-A-4-2809.
97 gazettes, Japanese Patent Application No. 2-158795, Japanese Patent Application No. 3-1
50083, Japanese Patent Application No. 3-187376, Japanese Patent Application No. 3-18
8829, Japanese Patent Application No. 3-187377, Japanese Patent Application No. 3-18
8830, Japanese Patent Application No. 3-294204, Japanese Patent Application No. 3-289
849 and Japanese Patent Application No. 4-9701 can also be used. As the treatment liquid, Japanese Patent Laid-Open No.
-253596, JP-A-62-82089, JP-A-1-
Of course, the liquids such as 133394, Japanese Patent Application Laid-Open No. 54-32424, Japanese Patent Application No. 3-159901 and Japanese Patent Application No. 3-197306 can also be used.

After forming the anodized film as described above,
In order to optimize the adhesion between each support and the photosensitive composition, after etching the anodic oxide film, water vapor and
There is an apparatus for sealing a support, which provides a photosensitive printing plate which is subjected to sealing treatment with hot water and has good stability over time, good developability, and no stains on non-image areas. (No. 12518) The treatment may be performed after the film is formed by such an apparatus. In addition, Japanese Patent Application No. 4-33952 and Japanese Patent Application No. 4-3395.
1, Japanese Patent Application No. 3-315245, JP-A-4-4
The sealing treatment may be performed by the device and method described in Japanese Patent No. 194, etc.

In addition, the treatment with potassium fluorozirconate described in US Pat. No. 2,946,638, the treatment with phosphomolybdate described in US Pat. No. 3,201,247, and British Patent No. 1108559. Alkyl titanate treatment, German Patent No. 10
No. 91433 specification, polyacrylic acid treatment, German Patent No. 1134093 and British Patent No. 1
Polyvinylphosphonic acid treatment described in JP-A-230447, phosphonic acid treatment described in JP-B-44-6409, phytic acid treatment described in US Pat. No. 3,307,951, JP-A-58-
As described in U.S. Pat. No. 3,860,426, treatment with a salt of a lipophilic organic polymer compound and a divalent metal described in JP-A No. 16893 and JP-A-58-18291. Alternatively, an undercoat layer of hydrophilic cellulose (eg, carboxymethyl cellulose) containing a water-soluble metal salt (eg, zinc acetate) may be provided, or JP-A-59-59
Of the water-soluble polymer having a sulfonic acid group described in JP-A-101651, which is hydrophilized by undercoating, and the phosphate described in JP-A-62-01494, Water-soluble epoxy compounds described in JP-A-62-033692, JP-A-62-09
Phosphoric acid-modified starch described in Japanese Patent No. 7892, JP-A-Sho 6
3-056498, diamine compounds described in JP-A-63-130391, inorganic or organic acids of amino acids, JP-A-63-145092-
Organic phosphonic acid containing COOH or --OH
Compounds having an amino group and a phosphonic acid group described in JP-A-3-165183, a specific carboxylic acid derivative described in JP-A-2-316290, and JP-A-3-215095.
The phosphoric acid ester described in JP-A-3-26159
Compounds having one amino group and one oxygen atom group of phosphorus described in JP-A No. 2-212058, and aliphatic or aromatic phosphones such as phenylphosphonic acid in addition to the phosphoric acid ester described in JP-A-3-215095. Acid, compounds containing S atom such as thiosalicylic acid described in JP-A-1-307745, compounds having phosphorus oxygen acid group described in JP-A-4-282637, and undercoating of JP-A- 60
Coloring with an acid dye described in JP-A-64352 may also be performed.

The support of the present invention may be provided with a photosensitive layer exemplified below to form a photosensitive lithographic printing plate. [I] In the case of providing a photosensitive layer containing an o-naphthoquinonediazide sulfonate and a phenol / cresol mixed novolak resin. The o-quinonediazide compound is an o-naphthoquinonediazide compound, for example, US Pat. Nos. 2,766,118 and 2,767,09.
No. 2, No. 2,772,972, No. 2,859,1
No. 12, No. 3,102,809, No. 3,106,
No. 465, No. 3,635,709, No. 3,64
It is described in a large number of publications including each specification of No. 7,443, and these can be preferably used. Among these, o-naphthoquinone diazide sulfonic acid ester or o-naphthoquinone diazide carboxylic acid ester of aromatic hydroxy compound, and o-naphthoquinone diazide sulfonic acid amide or o-naphthoquinone diazide carboxylic acid amide of aromatic amino compound are particularly preferable. , Especially those obtained by esterifying o-naphthoquinonediazide sulfonic acid with a condensate of pyrogallol and acetone described in US Pat. No. 3,635,709, US Pat. No. 4,028,111. A polyester having a hydroxy group at the terminal described in (1) and an ester reaction of o-naphthoquinone diazide sulfonic acid or o-naphthoquinone diazide carboxylic acid, described in British Patent No. 1,494,043 Such p-hydroxy Styrene homopolymers or copolymers thereof with other copolymerizable monomers which are esterified with o-naphthoquinone diazide sulfonic acid or o-naphthoquinone diazide carboxylic acid, US Pat. No. 3,759,711. P- as described in the specification
O-naphthoquinone diazide sulfonic acid, or o-
The amide reaction of naphthoquinone diazide carboxylic acid is very excellent.

These o-quinonediazide compounds can be used alone, but are preferably mixed with an alkali-soluble resin. Suitable alkali-soluble resins include novolac type phenol resins, and specifically include phenol formaldehyde resin, o-cresol formaldehyde resin, m-cresol formaldehyde resin and the like. Further, U.S. Pat. No. 4,028,
As described in Japanese Patent No. 111, a condensate of formaldehyde and phenol or cresol substituted with an alkyl group having 3 to 8 carbon atoms such as t-butylphenolformaldehyde resin is used together with the above-mentioned phenol resin. Then, it is even more preferable.

Further, in order to form a visible image upon exposure, o-naphthoquinonediazide-4-sulfonyl chloride, inorganic anion salt of p-diazodiphenylamine, trihalomethyloxadiazole compound, trihalomethyloxadiazole having a benzofuran ring. A compound such as a compound is added. On the other hand, as a colorant for the image, a triphenylmethane dye such as Victoria Bull-BOH, crystal violet or oil blue is used.
Further, the dyes described in JP-A-62-293247 are particularly preferable.

Further, as an oil sensitizer, JP-B-57-23
No. 253, a phenol substituted with an alkyl group having 3 to 15 carbon atoms, such as t-butylphenol, N-octylphenol, a novolak resin obtained by condensing t-butylphenol and formaldehyde, or A novolak resin o-naphthoquinonediazide-4- or -5-sulfonic acid ester (for example, described in JP-A-61-242446) can be contained.

Further, in order to improve the developability, a nonionic surfactant as described in JP-A-62-251740 can be further contained. The above composition is dissolved in a solvent that dissolves the above components and applied on a support. As the solvent used here, ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, lactic acid Methyl, ethyl lactate, dimethylsulfoxide, dimethylacetamide, dimethylformamide, water, N-methylpyrrolidone, tetrahydrofurfuryl alcohol, acetone, diacetone alcohol, methanol, ethanol, isopropanol, diethylene glycol dimethyl ether, etc. are available. Use by mixing.

A photosensitive composition comprising these components is provided in a solid content of 0.5 to 3.0 g / m ² .

[II] When providing a photosensitive layer containing a diazo resin and a water-insoluble and lipophilic photomolecular compound. As the diazo resin, for example, a diazo resin inorganic salt which is a reaction product of a condensate of p-diazodiphenylamine and formaldehyde or acetaldehyde, and a hexafluorophosphate or tetrafluoroborate soluble in an organic solvent, and US Pat. No. 3,300,309, wherein said condensate and a sulfonic acid such as paratoluenesulfonic acid or a salt thereof, a phosphinic acid such as benzenephosphinic acid or a salt thereof, a hydroxyl group-containing compound such as 2, 4-dihydroxybenzophenone, 2-
Examples thereof include organic solvent-soluble diazo resin organic acid salts which are reaction products of hydroxy-4-methoxybenzophenone-5-sulfonic acid or salts thereof.

Other diazo resins which can be preferably used in the present invention include carboxyl group, sulfonic acid group,
It is a co-condensate containing, as a structural unit, an aromatic compound having at least one organic group selected from the group consisting of a sulfinic acid group, an oxygen acid group of phosphorus and a hydroxyl group, and a diazonium compound, preferably an aromatic diazonium compound. And as the above-mentioned aromatic ring, a phenyl group and a naphthyl group can be preferably cited.

As the aromatic compound containing at least one of the above-mentioned carboxyl group, sulfonic acid group, sulfinic acid group, phosphorus oxyacid group, and hydroxyl group, various compounds can be mentioned, but the preferred ones are: 4-methoxybenzoic acid, 3-chlorobenzoic acid, 2,4-dimethoxybenzoic acid, p-phenoxybenzoic acid, 4-anilinobenzoic acid, phenoxyacetic acid, phenylacetic acid, p-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid Acid, benzenesulfonic acid, p-toluenesulfinic acid, 1-naphthalenesulfonic acid, phenylphosphoric acid, phenylphosphonic acid. The aromatic diazonium compound forming the constitutional unit of the above-mentioned co-condensed diazo resin includes, for example, Japanese Patent Publication No. 49-48001.
Although diazonium salts such as those listed in JP-A No. 1994-242242 can be used, diphenylamine-4-diazonium salts are particularly preferable.

The diphenylamine-4-diazonium salts are derived from 4-amino-diphenylamines, and such 4-amine-diphenylamines include 4-amino-diphenylamine and 4-amino-3-.
Methoxy-diphenylamine, 4-amino-2-methoxy-diphenylamine, 4'-amino-2-methoxy-
Diphenylamine, 4'-amino-4-methoxy-diphenylamine, 4-amino-3-methyldiphenylamine, 4-amino-3-ethoxy-diphenylamine, 4
-Amino-3-β-hydroxyethoxydiphenylamine, 4-amino-diphenylamine-2-sulfonic acid,
4-amino-diphenylamine-2-carboxylic acid, 4-
Amino-diphenylamine-2'-carboxylic acid and the like can be mentioned, with particular preference given to 3-methoxy-4-amino-4.
-Diphenylamine and 4-amino-diphenylamine.

Further, as a diazo resin other than the co-condensation diazo resin with an aromatic compound having an acid group, Japanese Patent Application No. 1-13
No. 0493, JP-A-3-163551 and JP-A-3163551.
A diazo resin condensed with an aldehyde containing an acid group or an acetal compound thereof described in JP-A-253857 can also be preferably used. The counter anion of the diazo resin includes an anion that stably forms a salt with the diazo resin and makes the resin soluble in an organic solvent. These include organic carboxylic acids such as decanoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid and sulfonic acids, and typical examples thereof include fluoroalkanesulfonic acids such as methanesulfonic acid and trifluoromethanesulfonic acid. , Laurylsulfonic acid, dioctylsulfosuccinic acid, dicyclohexylsulfosuccinic acid, camphorsulfonic acid, tolyloxy-3-propanesulfonic acid, nonylphenoxy-
3-propanesulfonic acid, nonylphenoxy-4-butanesulfonic acid, dibutylphenoxy-3-propanesulfonic acid, diamylphenoxy-3-propanesulfonic acid, dinonylphenoxy-3-propanesulfonic acid, dibutylphenoxy-4-butane Sulfonic acid, dinonylphenoxy-4-butanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, mesitylenesulfonic acid, p-
Chlorobenzenesulfonic acid, 2,5-dichlorobenzenesulfonic acid, sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, p-acetylbenzenesulfonic acid, 5
-Nitro-o-toluenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-chloro-5-nitrobenzenesulfonic acid, butylbenzenesulfonic acid, octylbenzenesulfonic acid, decylbenzene Sulfonic acid, dodecylbenzenesulfonic acid, butoxybenzenesulfonic acid, dodecyloxybenzenesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, isopropylnaphthalenesulfonic acid, butylnaphthalenesulfonic acid, hexylnaphthalenesulfonic acid, octyl Naphthalenesulfonic acid, butoxynaphthalenesulfonic acid, dodecyloxynaphthalenesulfonic acid, dibutylnaphthalenesulfonic acid, dioctylnaphthalenesulfonic acid, triisopropylnaphthalene Tarensuruhon acid, tributyl naphthalene sulfonic acid, 1-naphthol-5-sulfonic acid, naphthalene-1-sulfonic acid, naphthalene-2
Sulfonic acid, 1,8-dinitro-naphthalene-3,6-
Aliphatic and aromatic sulfonic acids such as disulfonic acid and dimethyl-5-sulfoisophthalate, 2,2 ', 4,4'
-A hydroxyl group-containing aromatic compound such as tetrahydroxybenzophenone, 1,2,3-trihydrooxybenzophenone and 2,2'4-trihydroxybenzophenone, a halogenated Lewis acid such as hexafluorophosphoric acid and tetrafluoroboric acid, ClO _4, like perhalogenic acid IO ₄ and the like although not limited thereto. Among these, particularly preferable ones are butylnaphthalenesulfonic acid, dibutylnaphthalenesulfonic acid, hexafluorophosphoric acid, 2-hydroxy-4-methoxybenzophenone-
5-sulfonic acid and dodecylbenzenesulfonic acid.

The diazo resin used in the present invention can have an arbitrary molecular weight by varying the molar ratio of each monomer and the condensation conditions, but it is effective for the intended purpose of the present invention. Molecular weight of about 400
100 to 100,000, preferably about 800 to 8,
000 is suitable. Examples of the water-insoluble and lipophilic polymer compound include copolymers having the structural units of the monomers shown in (1) to (15) below and having a molecular weight of usually from 100,000 to 200,000. (1) Acrylamide, methacrylamide, acrylic acid ester, methacrylic acid ester and hydroxystyrene having an aromatic hydroxyl group, such as N- (4-
Hydroxyphenyl) acrylamide or N- (4-
Hydroxyphenyl) methacrylamide, o-, m-,
p-hydroxystyrene, o-, m-, p-hydroxyphenyl-acrylate or methacrylate, (2) acrylic acid ester having an aliphatic hydroxyl group, and methacrylic acid ester such as 2-hydroxyethyl acrylate or 2-hydroxyethyl Methacrylate, 4-hydroxybutyl methacrylate (3) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, etc. (4) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, acrylic acid Amyl, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, benzyl acrylate, -2-acrylic acid
(Substituted) alkyl acrylates such as chloroethyl, glycidyl acrylate, N-dimethylaminoethyl acrylate, (5) methyl methacrylate, ethyl methacrylate,
Propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, glycidyl methacrylate, N
(Substituted) alkyl methacrylate such as dimethylaminoethyl methacrylate, (6) acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N-ethyl acrylamide, N-hexyl methacrylamide, N-cyclohexyl acrylamide, N- Acrylamide or methacrylamide such as hydroxyethyl acrylamide, N-phenyl acrylamide, N-nitrophenyl acrylamide, N-ethyl-N-phenyl acrylamide, (7) ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, Vinyl ethers such as butyl vinyl ether, octyl vinyl ether and phenyl vinyl ether, (8) vinyl Vinyl esters such as cetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate, etc. (9) Styrenes such as styrene, α-methylstyrene, chloromethylstyrene, (10) Methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl Vinyl ketones such as ketone and phenyl vinyl ketone, (11) olefins such as ethylene, propylene, isobutylene, butadiene and isoprene, (12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile. Etc. (13) Unsaturated imides such as maleimide, N-acryloylacrylamide, N-acetylmethacrylamide, N-propionylmethacrylamide, N- (p-chlorobenzoyl) methacrylamide, (14) N (o-amido) Nosulfonylphenyl) methacrylamide, N- (m-aminosulfonylphenyl) methacrylamide, N- (p-amino) sulfonylphenylmethacrylamide, N- (1- (3-aminosulfonyl) naphthyl) methacrylamide, N- ( Methacrylic acid amides such as 2-aminosulfonylethyl) methacrylamide, and acrylamides having the same substituents as described above, o-aminosulfonylphenyl methacrylate, m-aminosulfonylphenyl methacrylate, p-aminosulfonylphenyl methacrylate. 1
Methacrylic acid esters such as-(3-aminosulfonylnaphthyl) methacrylate, and unsaturated sulfonamides such as acrylic acid esters having the same substituents as above, (15) N- (2- (methacryloyloxy) -ethyl ) -2,3-Dimethylmaleimide, vinyl cinnamate, and other unsaturated monomers having a crosslinkable group in the side chain. Further, a monomer copolymerizable with the above-mentioned monomer may be copolymerized. (16) Phenolic resins described in U.S. Pat. No. 3,751,257 and polyvinyl acetal resins such as polyvinyl formal resin and polyvinyl butyral resin. (17) JP-B-54 with solubilized polyurethane in alkali
-19773, JP-A-57-904747, 60
-182437, 62-58242, 62-1
No. 23452, No. 62-123453, No. 63-11.
Polymer compounds described in JP-A No. 3450 and JP-A No. 2-146042.

The preferred molecular weight of the above copolymer is from 1 to 20.
In many cases. If necessary, polyvinyl butyral resin, polyurethane resin, polyamide resin, epoxy resin, novolac resin, natural resin, etc. may be added to the above copolymer. The photosensitive composition used for coating on the support of the present invention may further contain a dye for the purpose of obtaining a visible image by exposure and a visible image after development.

Examples of the dye include Victoria Pure-BOH [Hodogaya Chemical Co., Ltd.], Oil Blue #
603 [manufactured by Orient Chemical Industry], patent pure blue [manufactured by Sumitomo Mikuni Chemical Co., Ltd.], crystal violet,
Brilliant Green, Ethyl Violet, Methyl Violet, Methyl Green, Erythrosin B, Basic Fuchsin, Malachite Green, Oil Red, m
-Cresol purple, rhodamine B, auramine, 4
-P-diethylaminophenyliminaphthoquinone, cyano-p-diethylaminophenylacetanilide and other triphenylmethane-based, diphenylmethane-based,
Oxazine, xanthene, iminonaphthoquinone,
Examples of the discoloring agent in which an azomethine-based or anthraquinone-based dye changes from a colored color to a colorless or different colored color tone.

On the other hand, examples of the discoloring agent that changes from colorless to colored include leuco dyes and, for example, 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-anilinonaphthylmethane, p, Examples thereof include primary or secondary arylamine dyes represented by p ′, p ″ -triaminotriphenylmethane. Particularly preferably, triphenylmethane type and diphenylmethane type dyes are effectively used, more preferably triphenylmethane type dyes, and particularly Victoria Pure Blue BOH.

Various additives can be further added to the photosensitive composition used for the support of the present invention. For example,
Alkyl ethers (eg ethyl cellulose, methyl cellulose), fluorosurfactants and nonionic surfactants (especially fluorosurfactants are preferred) to improve coating properties, coating flexibility and abrasion resistance A plasticizer for imparting (eg, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofluleate oleate). Oligomer and polymer of furyl, acrylic acid or methacrylic acid, of which tricresyl phosphate is particularly preferable, and an oil sensitizer for improving the oil sensitivity of the image area (for example, styrene described in JP-A-55-527). Alcohol maleic anhydride copolymer Half ester product by, p-
Novolac resin such as t-butylphenol-formaldehyde resin, 50% fatty acid ester of p-hydroxystyrene, etc.), stabilizer {for example, phosphoric acid, phosphorous acid, organic acid (citric acid, oxalic acid, dipicolinic acid, benzenesulfonic acid) , Naphthalene sulfonic acid, sulfosalicylic acid,
4-methoxy-2-hydroxybenzophenone-5-sulfonic acid, tartaric acid, etc.), a development accelerator (eg higher alcohol, acid anhydride, etc.) and the like are preferably used.

To provide the above-mentioned photosensitive composition on a support, a photosensitive diazo resin, a lipophilic polymer compound and, if necessary, various additives are added in predetermined amounts in a suitable solvent (methyl cellosolve, ethyl). Cellosolve, dimethoxyethane, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, 1-methoxy-2-propanol, methyl cellosolve acetate, acetone, methyl ethyl ketone, methanol, dimethylformamide, dimethylacetamide, cyclohexanone, dioxane,
Tetrahydrofuran, methyl lactate, ethyl lactate, ethylene dichloride, dimethylsulfoxide, water or a mixture thereof) to prepare a coating solution of the photosensitive composition, which is coated on a support and dried.

The solvent used may be a single solvent, but it is more preferable to use a mixture of a high boiling point solvent such as methyl cellosolve, 1-methoxy-2-propanol and methyl lactate and a low boiling point solvent such as methanol and methyl ethyl ketone. The solid concentration of the photosensitive composition at the time of application is 1 to
It is desirable to set it in the range of 50% by weight. In this case, the coating amount of the photosensitive composition is about 0.2 to 10 g / m ²
It may be about (dry weight), more preferably 0.
It is good to set it to 5 to 3 g / m ² .

[III] When Providing a Photosensitive Layer Including a Photodimerizable Photosensitive Composition and a Photopolymerizable Photosensitive Composition The photodimerizable photosensitive composition includes a maleimide group, cinnamyl group, cinnamoyl group, cinnamylidene group, cinna Examples of the polymer having a side chain or a main chain such as a millidenacetyl group or a chalcone group are mentioned, and as a polymer having a maleimide group in the side chain, JP-A-52-988 (corresponding US Pat. No. 4,079,041) Gazette and German Patent Nos. 2 and 6
26,769, European Patent No. 21,019.
Specification, European Patent No. 3,552 and Die Angewandte Makromolekulare Chemie 115 (1
983), pages 163 to 181, the polymers described in JP-A-49-128991 and JP-A-49-128.
No. 992, No. 49-128993, No. 50-5376.
No. 50, No. 50-5377, No. 50-5379, No. 50
-5378, 50-50380, 53-5298.
No. 53-5299, No. 53-5300, No. 50
-50107, 51-47940, 52-13
907, 50-45076, 52-12170.
No. 0, No. 50-10884, No. 50-45087, and German Patent Nos. 2,349,948 and 2,6.
The polymer etc. which are described in each specification of 16,276 can be mentioned.

In order to make these polymers soluble or swellable in alkaline water, they dissociate into carboxylic acid / sulfonic acid, phosphoric acid, phosphonic acid, their alcal metal salts and ammonium salts, and alkaline water. pK
It is useful to include an acid group having a of 6 to 12 in the polymer. If necessary, monomers 1 to 1 having the above acid group
It is also possible to copolymerize the three types with a monomer having a maleimide group.

The acid value of the maleimide polymer having an acid group is preferably in the range of 30 to 300, and among the polymers having such an acid value, Die Angewandte Makromoleku.
lare Chemie) 128 (1984), pp. 71-91, a copolymer of N- [2- (methacryloyloxy) ethyl] -2,3-dimethylmaleimide and methacrylic acid or acrylic acid. It is useful.
Furthermore, a multi-component copolymer suitable for the purpose can be easily synthesized by copolymerizing the vinyl monomer as the third component in the synthesis of this copolymer. For example, by using as the third component vinyl monomer, an alkyl methacrylate or an alkyl acrylate whose homopolymer has a glass transition point of room temperature or lower, flexibility can be imparted to the copolymer.

As the photocrosslinkable polymer having a cinnamyl group, a cinnamoyl group, a cinnamylidene group, a cinnamylidene acetyl group or a chalcone group in the side chain or the main chain, US Pat. No. 3,030,208, US patent application 7
There are photosensitive polyesters described in each specification of 09,496 and 828,455. Examples of the photo-crosslinkable polymer solubilized in alkaline water include the following.

That is, a photosensitive polymer as described in JP-A-60-191244 can be mentioned. Further, JP-A-62-175529 and JP-A-6-175729
Examples thereof include photosensitive polymers described in JP-A No. 2-175730, JP-A-63-25443, JP-A-63-218944, and JP-A-63-218945.

Further, a sensitizer can be used in the photosensitive layer containing them, and as such a sensitizer, a benzophenone derivative, a benzanthrone derivative, a quinone, an aromatic nitro compound, a naphthothiazoline derivative, Examples thereof include benzothiazoline derivatives, thioxanthones, naphthothiazole derivatives, ketocoumarin compounds, benzothiazole derivatives, naphthofuranone compounds, pyrylium salts, and thiabilylium salts. Such a photosensitive layer may optionally contain chlorinated polyethylene, chlorinated polypropylene, polyacrylic acid alkyl ester, acrylic acid alkyl ester, acrylonitrile, vinyl chloride,
Styrene, copolymers with at least one monomer such as butadiene, polyamide, methyl cellulose, polyvinyl formal, polyvinyl butyral, methacrylic acid copolymer, acrylic acid copolymer, itaconic acid copolymer and other binders, dibutyl phthalate It is possible to use plasticizers such as phthalic acid dialkyl esters such as dihexyl phthalate, oligoethylene glycol alkyl esters, and phosphoric acid esters. Further, for the purpose of coloring the photosensitive layer, p is used as a dye or pigment or a printing-out agent.
It is also preferable to add an H-supporting agent or the like.

Examples of the photopolymerizable photosensitive composition include unsaturated carboxylic acids and salts thereof, esters of unsaturated carboxylic acids with aliphatic polyhydric alcohol compounds, and amides of unsaturated carboxylic acids with aliphatic polyvalent amine compounds. And so on. As the photopolymerization initiator, vicinal polytaketaldonyl compound, α-carbonyl compound, acyloin ether, α-
Aromatic acyloin compounds substituted with hydrocarbons at positions, polynuclear quinone compounds, triallyl imidazole dimers / p
-A combination of aminophenyl ketones, benzothiazole compounds, trihalomethyl-s-triazine compounds,
Acridine and phenazine compounds, oxadiazole compounds, etc. are included, and together with these, benzyl (meth) acrylate / (meth) acrylic acid / necessary as a high-molecular polymer that is soluble or swellable in alkaline water and capable of forming a film. Other addition-polymerizable vinyl monomer copolymers, methacrylic acid / methyl methacrylate (or methacrylic acid ester) copolymers, maleic anhydride copolymers with pentaerythritol triacrylate added by half-esterification And acidic vinyl copolymers.

[IV] Electrophotographic Photosensitive Layer For example, a ZnO photosensitive layer disclosed in US Pat. No. 3,001,872 can be used. Also, JP-A-56-161550 and JP-A-60-186847.
A photosensitive layer using an electrophotographic photoreceptor described in JP-A-61-238063 and the like may be used.

[0048] The amount of the photosensitive layer provided on the support, by dry weight after application, from about 0.1 to about 7 g / m ^2, preferably in the range of 0.5-4 g / m ^2.

When making a lithographic printing plate, if necessary, for the purpose of enhancing the adhesion between the support and the photosensitive layer, preventing the photosensitive layer from remaining after development, or preventing halation. An intermediate layer may be provided. In order to improve the adhesiveness, the intermediate layer is generally made of a diazo resin or a phosphoric acid compound, an amino compound, a carboxylic acid compound or the like which is adsorbed on aluminum. The intermediate layer made of a highly soluble substance so that the photosensitive layer does not remain after development is generally made of a highly soluble polymer or a water-soluble polymer. Further, for antihalation, the intermediate layer generally contains a dye or a UV absorber. The thickness of the intermediate layer is arbitrary, and must be such that it can undergo a uniform bond forming reaction with the upper photosensitive layer when exposed. Normally, a dry solid coating rate of about 1-100 mg / m ² is good, 5-40 m
g / m ² is particularly good.

On the coated photosensitive layer, a mat layer composed of protrusions provided independently of each other may be provided. The purpose of the matte layer is to improve the vacuum adhesion between the negative image film and the photosensitive lithographic printing plate during contact exposure, thereby shortening the vacuuming time and preventing the collapse of fine halftone dots during exposure due to poor adhesion. That is.

A method for applying the matte layer is described in JP-A-55 / 55.
No. 12974/1990, a method for heat-sealing powdered solid powder, JP-A-58-18263
There is a method of spraying polymer-containing water described in Japanese Patent Publication No. 6 and drying, and any method may be used. However, the mat layer itself dissolves in an aqueous alkaline developer containing substantially no organic solvent, or Those that can be removed are desirable.

The photosensitive lithographic printing plate prepared as described above is subjected to imagewise exposure, and then a resin image is formed by a process including development by a conventional method. For example, in the case of the photosensitive lithographic printing plate having the photosensitive layer of the above [I], it is exposed by imagewise exposure and then development by an aqueous alkali solution as described in US Pat. No. 4,259,434. A part is removed to obtain a lithographic printing plate, and in the case of a photosensitive lithographic printing plate having a photosensitive layer of [II], it is described in US Pat. No. 4,186,006 after image exposure. With such a developing solution, the unexposed area of the photosensitive layer is removed by development to obtain a lithographic printing plate. In addition, JP-A-59-
Use of an aqueous alkaline developer composition used for developing a positive working lithographic printing plate as described in JP-A-84241, JP-A-57-192952 and JP-A-62-24263. You can also

[0053]

EXAMPLES The present invention will be described below based on examples, but the present invention is not limited to the examples as long as the gist thereof is not exceeded. (Example-1) Average diameter 1 μm, 3 μm, 5 μm, 8 μm
m, 20 μm of aluminum oxide coated on each plastic sheet and aluminum plate,
It was pressed by passing it once between the rolling rollers.

When the surface of the aluminum plate after pressing was observed with a scanning electron microscope, each had an average diameter of 1 μm.
m, 3 .mu.m, 5 .mu.m, 8 .mu.m, 20 .mu.m were present as separate and uniform unevenness. The surface of the aluminum plate was polished to 1 g / m ^{2 in} an aqueous solution containing 5% of caustic soda at 60 ° C., washed with water, and then sulfuric acid 2 was added.
It was immersed in an aqueous solution containing 5% at 60 ° C. to remove the hydroxide on the surface of the aluminum plate and washed with water. Next, at 45 ° C. in an aqueous solution containing 1% nitric acid, a rectangular wave alternating current with a DUTY ratio of 1: 1 was used to electrochemically conduct at a current density of 25 A / dm ² until the amount of electricity on the anode side reached 160 C / dm ^2. The surface was roughened and washed with water. This aluminum plate is further added with sulfuric acid 2
It was immersed in an aqueous solution containing 5% at 60 ° C. for 60 seconds to remove the smut component mainly composed of aluminum hydroxide produced by electrochemical graining.

33 in an aqueous solution further containing 10% sulfuric acid
The aluminum plate is used as an anode at ℃, anodizing treatment is performed at a current density of 2 A / dm ² using a continuous DC power supply,
Alumite treatment was performed until the amount of anodized film reached 1.8 g / m ² , followed by washing with water and drying. A photosensitive layer was applied to these treated aluminum plates to prepare a printing plate. The printing plate having press recesses with an average diameter of 1 μm, 3 μm and 5 μm by pressing had good stain performance, but 8 μm
The smearing performance of the printing plate having the press recesses was slightly inferior, and the smearing performance of the printing plate having the press recesses of 20 μm was further inferior.

[0056]

EFFECT OF THE INVENTION A lithographic printing plate support having recesses of 6 μm or less that are not oriented by pressing has a surface suitable as a printing plate.

Claims (1)

[Claims] 1. A support for a lithographic printing plate, comprising a large number of press recesses having a non-directional average diameter of 6 μm or less on the surface of an aluminum plate.