JPH02229091A - Photosensitive lithographic printing plate - Google Patents

Abstract

PURPOSE:To improve a contamination at the time of printing by a method wherein the surface of an aluminum plate or a mechanically, electrically and/or chemically polished aluminum plate is treated with a metal or metallic oxide sol and, thereafter, a layer of a photosensitive composition is formed on the treated surface. CONSTITUTION:The surface of an aluminum plate serving as a substrate to be provided with a photosensitive layer is treated with a metal or metallic oxide sol. The sol is formed by using a metal or metallic oxide as a dispersion medium. As the metallic oxide, a hydrate may be used. As the metal or metallic oxide as a dispersoid, all materials being positively charged in the sol can be used. It is preferable that a cathode electrolytic process or a dipping treatment in a treating liquid consisting of a hydrosol containing the metal and/or metallic oxide as a dispersoid is employed as a surface sol treating method. The layer made of a photosensitive composition is provided on the surface treated with the metal or metallic oxide sol.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a photosensitive lithographic printing plate using an aluminum plate as a support.

[Background of the invention]

Conventionally, photosensitive lithographic printing plates have been made using an aluminum plate as a support, and a photosensitive layer whose solubility in a developing solution changes upon exposure to actinic rays is provided on the support. Widely used.

The composition of the photosensitive layer includes an 0-quinonediazide compound and a novolac type phenol resin as main components;
Some of the known methods include those mainly composed of diazo resin, and those composed of a polymerizable compound having an ethylenically unsaturated bond and a photopolymerization initiator. As a treatment method, a method of treating with a wood-philic polymer (polyvinyl alcohol, gelatin, polyphosphoric acid, etc.), an inorganic salt, an acid (for example, phytic acid), etc. are known.

Furthermore, JP-A-56-150595 describes a method of controlling the adhesive layer between the support and the photosensitive layer by subjecting the surface of the support to a sealing treatment with hot water, a sealing treatment with a silicate, etc. ing. In order to provide sufficient adhesion between the support and the photosensitive layer and to improve the hydrophilicity and water retention of the surface of the support, the support is further subjected to surface treatment. No. 22063, U.S. Pat. No. 2,246.

No. 683 and No. 3,160,506 disclose that the surface of a metal support is chemically treated with potassium fluorozirconate to form a film, thereby increasing the hydrophilicity and property of the metal surface. It has been shown that water retention can be improved.

Further, JP-A-53-131102 describes a support whose hydrophilicity and water retention are improved by treating it with an aqueous solution of potassium fluorozirconate and then with an aqueous solution of sodium silicate.

However, the photosensitive lithographic printing plates produced by these known techniques do not have sufficient stain generation characteristics during printing, and a photosensitive lithographic printing plate with improved stain generation is desired.

[Purpose of the invention]

Therefore, one object of the present invention is to provide a photosensitive lithographic printing plate with improved staining during printing.

[Structure of the invention]

The object of the present invention is to provide a photosensitive lithographic printing plate in which a layer made of a photosensitive composition is provided on an aluminum plate, the surface of the aluminum plate (the surface being protected from mechanical means, electrical means and chemical means). (including a surface polished by at least one selected means) with a metal or metal oxide vine, and then a layer of a photosensitive composition is provided on the treated surface. Achieved by a lithographic printing plate.

The present invention will be explained in detail below.

The present invention provides surface treatment (hereinafter referred to as "
It is characterized in that it is a surface that has been subjected to a surface treatment (sometimes referred to as "the surface treatment of the present invention").

In the production of photosensitive lithographic printing plates using an aluminum plate as a support, the surface of the aluminum plate on which the photosensitive layer is to be provided is usually subjected to surface treatments such as graining, anodizing, and if necessary, sealing. However, the aluminum plate to which the surface treatment of the present invention is applied may be an aluminum plate that has not been subjected to surface treatment such as graining, and the effects of the present invention can be obtained even with such an aluminum plate. I can do it.

Examples of the polishing method using mechanical means in the present invention include a pole polishing method, a brush polishing method, a polishing method by honing, and a buffing method.

Examples of polishing methods using electrical means include electropolishing methods. Chemical polishing methods include sulfuric acid,
Phosphoric acid, hydrochloric acid, nitric acid, oxalic acid, pyrophosphoric acid, dichloride
One possible method is etching with a solution containing iron or the like. Known methods can be applied to these treatments.

Preferred in the present invention is a method combining one or more of brush polishing methods, honing methods, and electrolytic polishing methods (especially in a hydrochloric acid bath and a nitric acid bath) (especially in a honing method and a nitric acid bath). (combination with electrolytic polishing).

Next, surface treatment using a metal or metal oxide sol in the present invention will be explained.

The sol used in the present invention is a sol using a metal or metal oxide as a dispersion medium, and the metal oxide may be a hydrate, and the metal or metal oxide as a dispersoid is positively charged in the sol. That's fine.

The metal forming the dispersoid and the metal of the metal oxide are A12
．． Ti Zr, Cr, Ni, Zn, Sn, Mn, Cu,
Co, Fe, Pb and Cd are preferred, and A12. is more preferred. Cr, Zr, Ni and Zn, particularly preferred are Aff, Zr and Ni.

In the sol used in the present invention, the metal and metal oxide are 2
More than one species can be mixed (this mixing may be done within the dispersoid particles or between the dispersoid particles) and used.

The particle size of the dispersoid made of metal or metal oxide is 1 to 500.
A range of nm is preferable; if it exceeds 500 nm, the adhesion of the sol to the aluminum plate will become non-uniform, and therefore the hydrophilicity will become non-uniform, and if it is less than 1 nm, it will be difficult to produce the sol, it will be very expensive, and it will be uneconomical. .

As the surface treatment method using a sol according to the present invention, it is preferable to perform cathodic electrolysis or immersion treatment in a geological fluid made of hydrosil containing metal and/or metal oxide as a dispersoid. The concentration of metals and metal oxides in the hydrosil is from 1 to
A range of 100g/+2 is preferred. The concentration is Ig/D,
If it is less than 100g, it will not be effective in influencing hydrophilicity, and the appearance of 100g will be significantly impaired, and at the same time, the sol will be unnecessarily consumed due to drag-out, etc., which is not preferable. The cathode electrolysis conditions vary depending on the type of sol used, but the current density is 5 to 1OA/dm2, and the treatment temperature is 5 to 50°C.
The appropriate processing time is in the range of 1-60 seconds.

Dispersoids of metals or metal oxides have a positive charge in hydrosil and are easily adsorbed to aluminum plates, and the bond after adsorption is strong, so simply immersing them in the treatment solution is effective. . In addition, even if it is dried as it is after immersion or washed with water and then dried, it shows good hydrophilicity, and the hydrophilicity lasts for a long time. Furthermore, since the dispersoids are positively charged in the sol, if electrolysis is carried out using an aluminum plate as a cathode, the metals and/or metal oxides that are the dispersoids will be electrophoretically adsorbed, and the dispersoids will be mixed with the metals and/or metal oxides. The bond with the aluminum plate becomes even stronger.

Further, in order to stabilize the sol, an inorganic acid such as chromic acid, phosphoric acid, sulfuric acid, or hydrochloric acid, an organic acid such as citric acid or acetic acid, or a surfactant may be added to the treatment liquid. Since these acids are easily removed by washing with water, they do not cause a decrease in corrosion resistance.

Since the hydrophilic film on the aluminum plate thus obtained is firmly bonded to the aluminum plate, it does not deteriorate over time. Further, it is preferable that the treatment liquid is neutral or weakly acidic and does not contain alkali ions.

In the present invention, a layer made of a photosensitive composition provided on a surface treated with a metal or metal oxide sol changes its solubility in a developer due to exposure to actinic rays, so that non-image areas are The photosensitive layer may be removed, and the removed portion may expose the support surface and become a non-image area, and may include a layer made of a known photosensitive composition that satisfies such conditions. Examples of such photosensitive compositions include the following.

(A) As a photosensitive component. - A photosensitive composition containing quinonediazide compound 41.

The 0-quinonediazide compound preferably contains at least one 0-quinonediazide group. -benzoquinonediazide group or. - Naphthoquinonediazide compounds with various known structures, such as the book by J. Kosar (Light)
t 5ensistive systemsJ (Joh
nWiley & 5ons, Inc., 1965) pages 339 to 353. Especially with various hydroxyl or amino compounds.

Esters or amides with naphthoquinonediazide sulfonic acid are preferred. Preferred hydroxyl compounds include condensation resins of phenols and carbonyl group-containing compounds, particularly resins obtained by condensation in the presence of an acidic catalyst. Examples of the phenols include phenol, resorcinol, cresol, pyrogallol, etc., and examples of the carbonyl group-containing compound include formaldehyde,
Examples include aldehydes such as benzaldehyde and ketones such as acetone.

Especially phenol/formaldehyde resin, cresol/
Formaldehyde resin, pyrogallol acetone resin,
Resorcinol benzaldehyde resin is preferred.

Typical specific examples of 0-quinonediazide compounds include:
Esters of benzoquinone-(1,2)-diazide sulfonic acid or naphthoquinone-(1,2)-diazide sulfonic acid with phenol-formaldehyde resins or cresol-formaldehyde resins, U.S. Pat. No. 3,635,
Naphthoquinone-(1,
2)-Diazide sulfonic acid and sulfonic acid ester of pyrogallol acetone resin, naphthoquinone (1,2)-diazide described in JP-A-54-1044
(2) Condensate of -5-sulfonic acid and resorcinol benzaldehyde resin, naphthoquinone-(1,2)diazide-(2) described in JP-A-55-76346.
) Ester compounds of 5-sulfonic acid and resorcinol/pyrogallol/acetone copolycondensate, and other useful 0-quinonediazide compounds are disclosed in JP-A-50-1175.
Ester of polyester having a hydroxyl group at the terminal and 0-naphthoquinonediazide sulfonic acid as described in Japanese Patent Publication No. 03, homopolymer of p-hydroxystyrene as described in Japanese Patent Application Laid-Open No. 113305/1983 Or a copolymer of this and other copolymerizable monomers. Examples include esters with -sufuthoquinone diazide sulfonic acid.

The content of these 0-quinonediazide compounds is preferably 5 to 60% by weight, particularly preferably 10 to 50% by weight, based on the total solid content of the photosensitive resist forming composition.

(B) A photosensitive composition containing a diazo compound as a photosensitive component.

As the aromatic diazonium salt, a diazo resin represented by a condensate of an aromatic diazonium salt and formaldehyde can also be used. Particularly preferred are salts of condensates of p-diazodiphenylamine and formaldehyde or acetaldehyde, such as diazo resin inorganic salts, such as hexafluorophosphates, tetrafluoroborates, perchlorates or periodates, and U.S. Pat. 3,300.309, sulfonic acids such as para-toluenesulfonic acid or its salts, phosphinic acids such as benzenephosphine ltl or its salts, phenolic hydroxyl group-containing compounds, For example 2
Examples include diazo resin functional salts which are reaction products with 4-dihydroxyl benzphenone.

Photosensitive compositions other than (C), (A) and (B).

Examples of the photosensitive component include a compound having an ethylenically unsaturated double bond that causes a photoduplexing reaction, a compound that causes a photopolymerization reaction, and a compound having a C-0-C group that is decomposed by an acid.

As examples of the former, those whose main component is a photosensitive polymer such as polyesters, polyamides, and polycarbonates containing -CB=CH-C- as a photosensitive group in the polymer main chain or side chain are also suitable. There is. For example, JP-A-55-404
15, a photosensitive polyester obtained by condensing phenylene diethyl acrylate with hydrogenated bisphenol A and triethylene glycol, as described in U.S. Pat. No. 2,956,878. Examples include photosensitive polyesters derived from (2-properidene)malonic acid compounds such as cinnamylidenemalonic acid and difunctional glycols.

Examples of the latter include acrylic acid or methacrylic acid ester derivatives, such as Japanese Patent Publications Nos. 35-5093 and 3514.
Examples include acrylic acid or methacrylic acid esters of polyols described in No. 719 publications, such as diethylene glycol (meth)acrylate and triethylene glycol (meth)acrylate.

Examples of the compound having a C-0-C group that can be decomposed with an acid include orthocarboxylic acid derivatives, monomeric or polymeric acetals, enol ethers, and acyliminocarbonates. As orthocarboxylic acid derivatives, for example, diphenoxy-methyl ethers of aliphatic or aromatic hydroxy compounds and N-diphenoxymethyl derivatives of lactams, which are described in U.S. Pat. No. 4,101.323, are used, and as polyacetals, For example, those having an aliphatic aldehyde unit and a diol unit as described in West German Patent No. 2.718.254 are used. For example, as an enol ether,
Among the orthoesters of the polymers described in DE 2,928,636, the alkyl ether group may be interrupted by an ether oxygen atom and is preferably bonded in the 5-position of the adjacent ring. A polymer having 1,3-dioxane-cyclohex-2-yl alkyl ether repeating units is used.

Examples of compounds that coexist with a compound having a C-0-C group and form or leave a strong acid upon exposure include diazonium, phosphonium, sulfolam and indonium salts, halogen compounds, 0-quinonediazide compounds,
Examples include organometallic organohalogen compositions, all organohalogen compounds used as photochemical radical initiators, s-1 riazine derivatives and oxadiazole derivatives substituted with halogenomethyl groups, and the like.

In addition to the materials described above, the photosensitive composition can also contain other additives as needed.

Various low-molecular compounds as plasticizers, such as heptatarate esters, triphenyl phosphates, maleate esters, acids as storage stabilizers for diazonium salts, such as oxalic acid and phosphoric acid, and surfactants as coating properties improvers. agents, such as fluorine-based surfactants, nonionic surfactants represented by ethyl cellulose polyalkylene ether, etc., acid anhydrides, etc. as sensitizers for positive photosensitive compositions, and furthermore, form visible images upon exposure to light. Examples include printout materials for The printout material consists of a compound that generates an acid or a free radical when exposed to light, and an organic dye that changes its color tone by interacting with it. As described in Publication No. 50-36209. -Naphthoquinonediazide-4-sulfonic acid halide, trihalomethyl-2-pyrone and trihalomethyl-triazine described in JP-A-53-36223, 0-naphthoquinonediazide-4 as described in JP-A-55-6244 Examples include ester compounds of -sulfonic acid chloride and phenols having electron-withdrawing substituents or anilines, halomethyl-vinyl-oxadiazole compounds and diazonium salts described in JP-A-55-77742.

Examples of the organic dyes include Victoria Pure Blue BOH [Hodogaya Chemical] and Oil Blue #603 [
Orient Chemical Industry], Patent Pure Blue [Sumitomo Mikuni Chemical 1, Crystal Violet, Brilliant Green, Ethyl Violet, Methyl Violet,
Triphenylmethane represented by methyl green, erythrosin B1 basic 7, malachite green, oil red, ■-cresol purple, rhodamine B1 auramine, 4-p-diethylaminophenylimino naphthoquinone, cyano-p-diethylaminophenyl acetalinide, etc. Examples thereof include diphenylmethane-based, oxazine-based, oxatene-based, iminonaphthoquinone-based, azomethine-based, and anthraquinone-based dyes.

A method of providing a layer made of the above photosensitive composition on a support,
A known method can be applied to develop the photosensitive lithographic printing plate obtained.

〔Example〕

Preparation of support Support = ■ After degreasing an aluminum plate with a thickness of 0.24 mm,
g/Q in a hydrochloric acid bath at a bath temperature of 25°C with a current density of 50
Electrolytic polishing treatment was performed for 25 seconds at 10 A/dm.
A desmut treatment was performed for 50° 013 seconds with an aqueous NaOH solution of g/I2.

Furthermore, 40% sulfuric acid aqueous solution, 30°C1 current density 1.5A/
Anodic oxidation treatment was performed at am2 for 2 minutes, and then hydrothermal treatment was performed for 25 seconds with an aqueous solution at 90°C.

Subsequently, as a hydrophilic treatment, Cr sol 2 with a particle size of 1100 nm was applied.
0g#2. Electrolysis was performed with a solution containing 10 g of phosphoric acid for 30 seconds at a current density of 2 A/dm2 using a steel plate as a cathode.
After washing with water and drying, Support-1 was obtained.

The surface roughness (Ra) of the completed support-1 is 0.5μ
It was m.

Support 2 Support 2 was prepared in the same manner as Support 1 except that the hydrophilic treatment was changed as described below.

Alumina sol with hydrophilic treatment and two particle diameters of 50 nm (Alumina sol-2009 handmade by Nissan Chemical) 30gIQ, chromic acid 5g
It was immersed in an aqueous solution containing IQ (25°060 seconds). R
a was 0.5 μm.

Support 3 Support 3 was prepared in the same manner as Support 1 except that the hydrophilic treatment was changed as described below.

Hydrophilic treatment: Immersed in an aqueous solution containing 30g/(1, phosphoric acid 10g#t) of zinc sol with a particle size of 40nm (25°C 6o seconds)
did.

Ra was 0.5 μm.

Support-4 After degreasing an aluminum plate with a thickness of 0.24 mm, 14
In a nitric acid bath of g/Q bath temperature 25°c1 current'a degree 50
Electrolytic polishing treatment was performed at A/dm2 for 30 seconds.

Next, 1Og/I2 NaOH aqueous solution 50'o, 13
Second desmut treatment was performed. Furthermore, 40% sulfuric acid aqueous solution, 3
0'0. Anodic oxidation treatment was performed for 2 minutes at a current density of 1.5 A/dm'', and then hydrothermal treatment was performed for 25 seconds in an aqueous solution at 90°C.

Subsequently, the same hydrophilic treatment as for Support-1 was performed to obtain Support-4. Ra was 0.49 μm.

Support-5 The surface of an aluminum plate with a thickness of 0.24 mm was grained using a nylon bra and 400 menonyu of pumice stone in water suspension, then thoroughly washed with water, and diluted with 1% NaOH aqueous solution for 13 minutes. Degreasing treatment was performed for seconds. Furthermore, 40% phosphoric acid,
At 30℃, 4. It was anodized for 30 seconds at a current density of OA/dm2 and treated with hot water at 90°C.

Subsequently, the same hydrophilic treatment as for Support-1 was performed to obtain Support-5. Ra was 0.5 μm.

Support-6 An aluminum plate with a thickness of 0.24 mm was subjected to liquid honing treatment, and then treated with a 10 g/i2 NaOH aqueous solution at 50°C.
Desmut treatment was performed for 13 seconds. Further, an anodic oxidation treatment was performed using a 40% sulfuric acid aqueous solution at 30° C. and a current density of 1.5 A/dm for 2 minutes, and then a hot water treatment was performed using a 90° C. aqueous solution for 25 seconds.

Subsequently, the same hydrophilic treatment as for Support-1 was performed to obtain Support-6. Ra was 0.5 μm.

Support-7 The aluminum plate immediately after brush polishing with support-5 was
Subsequently, electrolytic polishing was performed in a 14 g IQ nitric acid bath at a bath temperature of 25° C1 and a current density of 30 A/am2 for 30 seconds.

Next, NaO[-1 aqueous solution of Log/42 was used at 50°C11
Desmat treatment was performed for 3 seconds. Furthermore, 40% sulfuric acid aqueous solution,
Anodization treatment was performed for 2 minutes at 30°C9 with a current density of 1.5 A/dm'', followed by hot water treatment for 25 seconds in an aqueous solution at 90°C.

Subsequently, the same hydrophilic treatment as in Support-1 was performed to obtain Support-7. Ra was 0.49 μm.

Comparative support-1 A support that was not subjected to hydrophilic treatment in Support-7.

Comparative Support-2 A support obtained by treating Support-7 with a 1% sodium metasilicate aqueous solution at 80°C for 160 seconds instead of the hydrophilic treatment.

Preparation of photosensitive liquid Photosensitive liquid-1 Condensate of pyrogallol acetone resin and 0-naphthoquinonediazide-4-sulfonyl chloride...2.2 parts by weight (
Weight average molecular weight (Mw) of backbone polymer -2500°O
Condensation rate of H group: 33 mol%) Phenol/m-cresol/p-cresol (weight ratio 3:4:3) -Formalin novolac resin...8 parts by weight p-
Octylphenol ◆ Condensate of formalin novolak resin and 0-naphthoquinonediazide-5-sulfonyl chloride (Of(
Condensation rate of group 50 mol%) ...0.1 part by weight 2-trichloromethyl-β-(2'-benzofuryl)vinyl-1
, 3,4-oxadiazole...0.06 parts by weight Hyctoriafure Blue BOI (manufactured by Odugaya Chemical Co., Ltd.)...0,08 parts by weight Methyl cellosolve...10 parts by weight Ethyl cellosolve ...40 parts by weight Photosensitive liquid-2 PF, salt of condensate of p-diazodiphenylamine and paraformaldehyde (weight average molecular weight (Mw) = 2000)
...1 part by weight p-hydroxyphenyl methacrylamide, acrylonitrile, ethyl acrylate, methacrylic acid (molar ratio 8:20:65 nia) (M Il = 600
00) ... 9 parts by weight Polyacrylic acid (Jurimar ACIOL, manufactured by Nippon Pure Chemical Industries, Ltd.) ... 1 part by weight Victoria Pure Blue BOH (manufactured by Odugaya Chemical Co., Ltd.) ... 0.7 parts by weight methyl Cellosolve: 50 parts by weight Photosensitive lithographic printing plate samples No. 1-No. 16 were prepared using the combinations of the support and the photosensitive liquid shown in Table 1 below.

Plate making conditions for these photosensitive lithographic printing plate samples are shown below-1.
(Positive plate making), plate making condition -2 (Iga plate making),
Lithographic printing plates No. 1 to No. 16 were prepared.

Next, the printing plate was printed under the following printing conditions, and the printed matter was evaluated. In particular, printing was stopped after 1000 sheets had been printed, and after being left for 60 minutes, printing was restarted and the degree of occurrence of spot-like stains in non-print areas was checked.

Table 1 Exposure time: 70 seconds Film original: Kodak Step Tablet No.
, 2, halftone original development conditions Self-development: Konica PS version automatic development machine "'PSQ-860"
(manufactured by Konica Corporation) Developer: 6 times diluted solution of Konica PS plate developer "5DR-1" Development temperature: 27°C Development time: 20 seconds Plate making conditions -2 Exposure conditions = 42 seconds, otherwise the same as plate making condition -1.

Development conditions: 4-fold dilution of developer 5DN-21, other conditions are the same as plate-making conditions-1.

Exposure conditions Exposure machine: Metal halide lamp "Idolfun 2000"
8.0mW/m2 (manufactured by Iwasaki Electric) Printing conditions Printing machine: Heidel GTO ink: Collection Best Cure “BFWRO” (
Paper (manufactured by Sueya Shiki Co., Ltd.) Coated paper (A-2) Dampening water...
・50 times diluted liquid printing speed of "5EU-1"...
5000 sheets/hour 2.1 Staining during printing by a printing plate made from a photosensitive lithographic printing plate having a layer made of a photosensitive composition on its surface is improved.

＠, Non-wire area is completely clean.

○, There is some dirt on the non-printed areas.

×: There is dirt in the non-printing area.

〔Effect of the invention〕

Claims (1)

[Claims] After surface-treating an aluminum plate or a mechanically, electrically and/or chemically polished aluminum plate with a metal or metal oxide sol, a layer made of a photosensitive composition is provided on the surface-treated surface. A photosensitive lithographic printing plate characterized by the following properties: