JPH1191254A - Manufacture of support for lithographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To upgrade plate wear resistance and printing performance by roughing a support material made of aluminum or the like by chemical roughing, and specifying a ratio of maximum surface roughness before and after the roughing of the material, thereby upgrading dampening water retentivity at the time of offset printing. SOLUTION: A support for a lithographic printing plate is manufactured by degreasing support material made of aluminum or an aluminum alloy by solvent cleaning, then chemically roughing it, and roughing it so that a ratio of maximum surface roughness (Rmax) before and after the roughing becomes 1.2 times or more. A method for chemically roughing is a method for roughing by dipping it in water solution of acid or base and eroding a surface. As example of the base, an inorganic alkali salt such as sodium hydroxide, sodium carbonate or the like is used. of them, a water solution of an inorganic alkali salt is suitable, and its concentration is suitably 1 to 50 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention 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 for roughening a support material made of aluminum or an aluminum alloy.

[0002]

2. Description of the Related Art Conventionally, a lithographic printing plate support is generally obtained by subjecting a support material made of aluminum or an aluminum alloy to a surface roughening treatment. Mechanical graining treatment methods such as sandblasting, ball graining, brushing with a nylon brush and an abrasive / water slurry or honing grain spraying the abrasive / water slurry onto the surface at a high pressure, and etching comprising an alkali, an acid or a mixture thereof. There is a chemical surface roughening treatment method in which the surface is roughened with an agent. Also, for example, JP-A Nos. 52-152302 and 54-85802.
No. 55-158298, No. 58-120531
No., 60-147394, 56-28898,
JP-A-60-190392, JP-A-1-280590,
No. 1,148,592 and the like.
There is known a method in which a mechanical surface roughening method and an electrochemical surface roughening method described in JP-A-123204 and JP-A-54-63902 are combined.

[0003]

However, conventional chemical surface roughening methods, mechanical surface roughening methods, and electrochemical surface roughening methods have a proper surface roughness and a uniform pit shape. A support was not obtained, and therefore, when offset printing was performed using a lithographic printing plate obtained by applying and processing the photosensitive composition on the support, poor water retention was observed,
There are problems such as poor printing durability and poor printing performance.

Furthermore, the above-mentioned chemical surface roughening method has poor surface roughening performance, and is often used as an auxiliary means of a mechanical surface roughening method or an electrochemical surface roughening method. Although rough pit formation is possible by the mechanical surface roughening method, there is a problem that the uniformity is poor and the cost of the apparatus is high. In addition, the electrochemical surface roughening method produces a stable-quality support that tends to change its grain shape even when treated under the same electrolytic conditions due to variations in the amount of alloy components between lots of aluminum support material. It is difficult to perform the operation, and the cost is increased due to higher power consumption. These problems cannot be solved only by combining the surface roughening methods.

The present invention has been proposed based on the above-mentioned circumstances, and an object thereof is to provide a support having an appropriate surface roughness and a uniform pit shape at low cost.
Therefore, when offset printing is performed using a lithographic printing plate obtained by applying and processing a photosensitive composition on the support, the lithographic printing plate support is excellent in water retention, excellent in printing durability and printing performance. An object of the present invention is to provide a method for producing a body.

[0006]

The above object is achieved by the following constitution.

[0007] 1. In a method for producing a lithographic printing plate support, wherein a support material made of aluminum or an aluminum alloy is subjected to surface roughening treatment, the surface roughening treatment of the support material is a chemical surface roughening treatment, A method for producing a lithographic printing plate support, wherein the ratio of the maximum surface roughness (Rmax) before and after the surface roughening treatment is 1.2 times or more.

[0008] 2. In a method for producing a lithographic printing plate support, wherein a support material made of aluminum or an aluminum alloy is subjected to a surface roughening treatment, the surface roughening treatment of the support material is a chemical surface roughening treatment, and at least the surface roughening treatment is performed. A method for producing a support for a lithographic printing plate, characterized in that, at an initial stage of the treatment, there are a portion where the treatment liquid adheres to the support material and a portion where the treatment liquid does not adhere.

3. In a method of manufacturing a lithographic printing plate support for roughening a support material made of aluminum or an aluminum alloy, a roughening treatment is performed by providing a coated portion and an uncoated portion on the surface of the support material. A method for producing a lithographic printing plate support, characterized in that:

[0010] 4. In a method for producing a lithographic printing plate support for roughening a support material made of aluminum or an aluminum alloy, a chemical roughening treatment is performed after providing a coated portion and an uncoated portion on the surface of the support material. And a anodic oxidation treatment with or without removing the coated portion. A method for producing a lithographic printing plate support.

5. In a method for producing a lithographic printing plate support for roughening a support material made of aluminum or an aluminum alloy, a chemical roughening treatment is performed after providing a coated portion and an uncoated portion on the surface of the support material. And further performing at least one kind of surface roughening treatment selected from mechanical surface roughening treatment, chemical surface roughening treatment, and electrochemical surface roughening treatment with or without removing the coating portion. And a anodic oxidation treatment, followed by a method for producing a lithographic printing plate support.

6. In a method for producing a lithographic printing plate support, which comprises subjecting a support material made of aluminum or an aluminum alloy to a surface roughening treatment, the surface of the support material is provided with a coated portion and an uncoated portion, and then electrochemically roughened. Performing a treatment, and further removing or not removing the coating portion, mechanically roughening treatment, chemical roughening treatment, and at least one kind of roughening treatment selected from electrochemical roughening treatment. Do
Subsequently, an anodic oxidation treatment is performed.

7. In the method for producing a lithographic printing plate support for roughening a support material made of aluminum or an aluminum alloy, a coated portion and an uncoated portion are provided on the surface of the support material, and then the uncoated portion is provided. Performing a treatment for imparting corrosion resistance, and further removing or not removing the coating portion, at least one selected from a mechanical roughening treatment, a chemical roughening treatment, and an electrochemical roughening treatment. A method for producing a lithographic printing plate support, comprising performing a surface roughening treatment, followed by an anodizing treatment.

8. The means for providing a coating portion on the surface of a support material made of aluminum or an aluminum alloy is at least one type selected from a system using a spray gun, an inkjet system, and a printing system. 4. The method for producing a lithographic printing plate support according to claim 1.

Hereinafter, the present invention will be described in detail.

In the method for producing a lithographic printing plate according to the first aspect of the present invention, the lithographic printing plate support of the present invention is prepared by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by washing with a solvent, which will be described later. A chemical surface roughening treatment is performed, and the maximum surface roughness (R) before and after the chemical surface roughening treatment is obtained.
max) is roughened so that the ratio becomes 1.2 times or more, and is preferably obtained by anodizing.

In the method for producing a lithographic printing plate according to claim 2, the lithographic printing plate support of the present invention is obtained by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by solvent washing. An alkaline aqueous solution such as potassium hydroxide or sodium hydroxide is used in the initial stage of the chemical surface roughening treatment described below so that a portion where the alkaline aqueous solution adheres to the surface of the support material and a portion where the alkaline aqueous solution does not adhere are present ( After pre-treatment)
It is obtained by immersing it in a chemical surface roughening treatment liquid to perform a chemical surface roughening treatment, and preferably by anodizing.

In the method for producing a lithographic printing plate according to claim 3, the lithographic printing plate support of the present invention is obtained by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by solvent washing. A coated portion and an uncoated portion (dot-shaped coating layer) are provided on the surface of the support material using an aqueous solution of a silicate or a solution of an organic solvent of a resin, and a surface roughening treatment described later is performed. Obtained by processing.

More specifically, in the method for manufacturing a lithographic printing plate according to claim 4, the lithographic printing plate support of the present invention is obtained by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by solvent washing. After that, a coated portion and an uncoated portion (dot-shaped coating layer) are provided on the surface of the support material using an aqueous solution of a silicate or an organic solvent solution of a resin, and the like, and a chemical surface roughening treatment described later is performed. And anodizing treatment with or without removing the dot-shaped coating layer.

More specifically, in the method for producing a lithographic printing plate according to claim 5, the lithographic printing plate support of the present invention is obtained by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by solvent washing. After performing, a coated portion and an uncoated portion (dot-shaped coating layer) are provided on the surface of the support material using an aqueous solution of a silicate or an organic solvent solution of a resin, and then subjected to a chemical surface roughening treatment described later. And removing or not removing the dot-shaped coating layer, at least one kind of rough surface selected from mechanical roughening treatment, chemical roughening treatment, and electrochemical roughening treatment described below. And anodizing treatment.

More specifically, in the method for manufacturing a lithographic printing plate according to claim 6, the lithographic printing plate support of the present invention is obtained by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by solvent washing. After performing, a coated portion and an uncoated portion (dot-shaped coating layer) are provided on the surface of the support material using an aqueous solution of a silicate or a solution of an organic solvent of a resin or the like, and then the electrochemical surface roughening described later is performed. Treatment, with or without removing the dot-shaped coating layer, at least one kind of roughening treatment selected from mechanical roughening treatment, chemical roughening treatment, and electrochemical roughening treatment described below. Perform surface treatment,
And it is obtained by anodizing.

More specifically, in the method for producing a lithographic printing plate according to claim 7, the lithographic printing plate support of the present invention is obtained by subjecting a support material made of aluminum or an aluminum alloy to a degreasing treatment by solvent washing. After that, a coated portion and an uncoated portion (dot-shaped coating layer) are provided on the surface of the support material using an aqueous solution of a silicate or an organic solvent solution of a resin, and a corrosion resistance imparting treatment described later is performed. After performing a chemical surface roughening treatment or electrochemical surface roughening treatment described later, further removing or not removing the dot-shaped coating layer,
It is obtained by performing at least one kind of surface roughening treatment selected from a mechanical surface roughening treatment, a chemical surface roughening treatment, and an electrochemical surface roughening treatment, which will be described later, and performing an anodic oxidation treatment.

<Support Material> The support material of the present invention includes:
Pure aluminum plate or aluminum alloy plate is used,
Various things can be used for the aluminum alloy plate, for example, silicon, copper, manganese, magnesium, chromium, zinc,
An alloy of a metal such as lead, bismuth, nickel, titanium, sodium and iron and aluminum is used, and the maximum surface roughness (Rmax) of the support material before the surface roughening treatment is 1.0 to 1.0.
5.0 is preferably used.

<Degreasing treatment> The aluminum support material is
Prior to the surface roughening treatment, it is preferable to perform a degreasing treatment to remove the rolling oil on the aluminum surface. Examples of the degreasing treatment include a degreasing treatment using a solvent such as trichlene or thinner, and an emulsion degreasing treatment using an emulsion such as kesilon or triethanol. In the degreasing treatment, an aqueous solution of an alkali such as caustic soda can be used. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, dirt and oxide film that cannot be removed by the above degreasing treatment alone can also be removed. When an alkaline aqueous solution such as caustic soda is used for degreasing, phosphoric acid, nitric acid,
It is preferable to immerse in an acid such as hydrochloric acid, sulfuric acid, and chromic acid, or a mixed acid thereof to perform a neutralization treatment. When the electrochemical surface-roughening treatment is performed after the neutralization treatment, it is preferable to match the acid used for the neutralization with the acid used for the electrochemical surface-roughening treatment.

<Pretreatment with an Aqueous Alkaline Solution> Prior to the chemical surface-roughening treatment, the support material subjected to the degreasing treatment is pre-dotted with an alkali aqueous solution of an alkali metal or alkaline earth metal oxide or hydroxide. After the treatment, the surface may be immersed in the alkaline aqueous solution to perform the chemical surface roughening treatment.

<Coating treatment> A coated portion and an uncoated portion (dot-shaped coating layer) are formed on the surface of the support material which has been degreased.
The coating treatment for forming the resin is carried out by an alkali-soluble resin described later, JP-A-57-34558 and JP-A-7-20.
Dot coating with a solution of a polymer compound (including a plasticizer) described in Japanese Patent No. 5563 in an organic solvent,
This is carried out by coating in the form of dots using an aqueous solution of an alkali metal or alkaline earth metal silicate.

The concentration of the solution obtained by dissolving the resin or the polymer compound in an organic solvent is 10 to 50% by weight, and the alkali metal or alkaline earth metal oxide, hydroxide,
The concentration of the aqueous solution of silicate or the like is preferably 10 to 30 wt%. The alkali-soluble resin that can be used in the present invention is not particularly limited. Examples thereof include a novolak resin, a vinyl polymer having a phenolic hydroxyl group, and a polyhydric phenol and aldehyde described in JP-A-55-57841. Alternatively, a condensation resin with a ketone may be used. Novolak resins usable in the present invention include, for example, phenol / formaldehyde resins, cresol / formaldehyde resins, and JP-A-55-5784.
Phenol / cresol / formaldehyde copolymer resin described in JP-A No. 1 and JP-A-55-127553.
-Copolymer resins of substituted phenol and phenol or cresol and formaldehyde. The molecular weight (polystyrene standard) of the novolak resin preferably has a number average molecular weight Mn of 3.00 × 10 ^{2 to} 7.50 × 1.
0 ³ , weight average molecular weight Mw of 1.00 × 10 ^{3 to} 3.00
× 10 ⁴ , more preferably Mn is 5.00 × 10 ² to 4.
00 × 10 ³ , Mw is 3.00 × 10 ^{3 to} 2.00 × 10 ^3
4 The above novolak resins may be used alone or in combination of two or more. The vinyl polymer having a phenolic hydroxyl group is a copolymer having a unit having the phenolic hydroxyl group in a molecular structure, and a structural unit represented by the following general formulas (1) to (5): Polymers containing at least one are preferred.

[0028]

Embedded image

In the general formulas (1) to (5), R ₁ and R ₂ each represent a hydrogen atom, an alkyl group or a carboxyl group, preferably a hydrogen atom. R ₃ represents a hydrogen atom, a halogen atom or an alkyl group, preferably a hydrogen atom, an alkyl group such as a methyl group or an ethyl group. R ₄ represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and is preferably a hydrogen atom. A represents an alkylene group which may have a substituent linking a nitrogen atom or an oxygen atom to an aromatic carbon atom;
And B represents a phenylene group which may have a substituent or a naphthylene group which may have a substituent.

The vinyl polymer having a phenolic hydroxyl group used in the present invention has an aromatic polyhydric alcohol having a phenolic hydroxyl group and having the structural units represented by the general formulas (1) to (5). And a monomer type copolymerizable with the polyhydric alcohol.

The monomers copolymerizable with the polyhydric alcohol include, for example, ethylenically unsaturated olefins such as ethylene, propylene, isobutylene, butadiene and isoprene, for example, styrene, α-methylstyrene, p-
Styrenes such as methylstyrene and p-chlorostyrene,
Acrylic acids such as acrylic acid methacrylic acid, for example, unsaturated aliphatic dicarboxylic acids such as itaconic acid, maleic acid, maleic anhydride, for example, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, acrylic acid Dodecyl, 2-chloroethyl acrylate, phenyl acrylate, benzyl methacrylate,
Esters of α-methylene aliphatic monocarboxylic acids such as α-methyl chloroacrylate, methyl methacrylate, ethyl methacrylate and ethyl ethacrylate, for example, nitriles such as acrylonitrile and methacrylonitrile, for example, acrylamide, methacrylamide, N- sec-butylacrylamide, N-tert-butylacrylamide, N, N-dibutylacrylamide, N-tert
Amides such as -butylmethacrylamide, for example, anilides such as acrylanilide, p-chloroacrylanilide, m-nitroacrylanilide, and m-methoxyacrylanilide, for example, vinyl acetate, vinyl propionate,
Vinyl esters such as vinyl butyrate and vinyl benzoate,
For example, methyl vinyl ether, ethyl vinyl ether,
Vinyl ethers such as isobutyl vinyl ether and β-chloroethyl vinyl ether, vinyl chloride, vinylidene chloride, vinylidene cyanide, for example, 1-methyl-1-
Methoxyethylene, 1,1-dimethoxyethylene, 1,
Ethylene derivatives such as 2-dimethoxyethylene, 1,1-dimethoxycarbonylethylene, 1-methyl-1-nitroethylene, for example, N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidene, -N-vinyl monomers such as vinylpyrrolidone, and the N-vinyl monomers are present in the polymer compound in a structure in which unsaturated double bonds are cleaved.

Among the monomers copolymerizable with the above-mentioned aromatic polyhydric alcohol having a phenolic hydroxyl group, esters and nitriles of aliphatic monocarboxylic acids have excellent performance. May be bound in a block or random state in a vinyl polymer having The vinyl polymer having a phenolic hydroxyl group may be used alone or in combination of two or more. Further, it can be used in combination with another polymer compound or the like.

<Organic Solvent> Examples of the solvent for the alkali-soluble resin include aliphatic alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol, n-pentanol, hexanol and heptanol; allyl alcohol; Benzyl alcohol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, ethylene glycol monoacetate, ethylene glycol diacetate, propylene glycol diacetate, ethylene glycol alkyl ethers and their acetates (methylcellosolve, ethylcellosolve, butylcellosolve, Phenyl cellosolve, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, methyl cellosolve acetate Ethylcellosolve acetate), diethylene glycol monoalkyl ethers and their acetates (diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono i-propyl ether, diethylene glycol monobutyl ether, diethylene glycol monomethyl ether acetate, etc.), diethylene glycol dialkyl ethers (diethylene glycol dimethyl ether, Diethylene glycol diethyl ether, diethylene glycol methyl butyl ether, diethylene glycol dii-propyl ether, diethylene glycol dibutyl ether, etc.), propylene glycol alkyl ethers and their acetates (propylene glycol monomethyl ether, propylene glycol). Glycol monoethyl ether, propylene glycol n-propyl ether, propylene glycol monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc.), dipropylene glycol alkyl ethers Propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether,
Dipropylene glycol methyl ethyl ether, etc.), triethylene glycol alkyl ethers (triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol methyl ethyl ether, etc.), anisole Phenetol, diacetone alcohol, 3-methoxy-1-butanol, 4-methoxy-1
-Butanol, 3-ethoxy-1-butanol, 3-methoxy-3-methyl-1-butanol, 3-methoxy-
3-ethyl-1-pentanol, 4-ethoxy-1-
Pentanol, 5-methoxy-1-hexanol, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, methyl pentyl ketone, methyl hexyl ketone, ethyl butyl ketone, dibutyl ketone, cyclopentanone, cyclohexanone, methyl cyclohexanone, γ-butyrolactone,
3-hydroxy-2-butanone, 4-hydroxy-2-
Butanone, 4-hydroxy-2-pentanone, 5-hydroxy-2-pentanone, 4-hydroxy-3-pentanone, 6-hydroxy-2-hexanone, 3-methyl-
Ketones such as 3-hydroxy-2-pentanone, ethyl formate, propyl formate, butyl formate, amyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, etc. Aliphatic carboxylic acid esters, n-hexane, heptane, octane, nonane, hydrocarbons such as decane, methyl benzoate, ethyl benzoate, propylene carbonate, methyl lactate, ethyl lactate, dimethylformamide,
Dimethyl sulfoxide, dioxane, tetrahydrofuran and the like can be mentioned. The organic solvent may be used alone or in combination of two or more, and preferably has a boiling point of 75 to 200 ° C.

<< Coating Treatment Method >> As a method of forming a dot-shaped coating layer by attaching a silicate aqueous solution or a solution of an organic solvent of a resin to the surface of a support material, for example, spraying with a spray gun, an ink jet method, printing, etc. Examples of the printing include letterpress printing, gravure printing, thermal transfer, sublimation thermal transfer, and fusion thermal transfer. Preferably, it is sprayed with a spray gun and fixed on the surface of the support, and dried.

<< Regulation on Dot-Shaped Coating Portion >> The dot-shaped coating layer formed by applying a silicate aqueous solution or a solution of an organic solvent of a resin onto the surface of the support material in a dot-like manner has a dot height after drying. Is 1 to 20 μm and the width is 20 to 20
0 μm, the amount of the dot-shaped covering portion is 1 to 1000 pieces /
mm ² .

<< Spray Gun >> As a method for forming the above-mentioned dot-shaped coating layer, a spray method is preferable. In the spray method, a solution is atomized and the fine particles are caused to fly to an object to be coated (support material). To adhere,
For example, an air spray, an airless spray, an electrostatic air spray, an electrostatic atomization spray and the like are included. The distance between the spray gun used in the spray method and the surface of the support is usually 30 to 150 cm, more preferably 30 to 10 cm.
0 cm, and the viscosity of the spray liquid when it reaches the support surface is usually 2000 to 8000 cp, preferably 3000 to 7 cp.
000 cp.

<< Drying Method >> In hot air drying, the drying temperature is preferably 30 to 200 ° C., more preferably 50 to 130 ° C.
The drying time is appropriately selected depending on the drying temperature. I
In the R drying, the plate surface temperature is set to 30 to 130 ° C., and the drying time in the IR drying is appropriately selected according to the capability of the IR heater.

<Corrosion-resistant treatment> The surface of the support material which has been coated in the above-mentioned dot form may be coated, if necessary, with, for example, JP-A-6-35174, JP-A-6-230563 and JP-A-7-205563. For example, a corrosion-resistant treatment using a metal oxide and an organic polymer compound prepared by the method described in each of the above publications, for example, a sol-gel reaction solution containing tetraethylsilicate is applied and dried to carry out a corrosion-resistant treatment.

<Roughening treatment> As described above, the support material which has been coated in the form of dots and, if necessary, has been subjected to a corrosion-resistant treatment is subjected to a chemical roughening treatment, an electrochemical roughening treatment, or the like. Alternatively, the surface is roughened by a roughening method combining these. If necessary, these surface roughening methods may be used in combination with a mechanical surface roughening method.

<< Mechanical Surface Roughening Method >> The mechanical surface roughening method is not particularly limited, but brush polishing and honing polishing are preferable. In brush polishing, for example, a hair diameter of 0.2 to
The surface of the support is roughened by rotating a cylindrical brush with 1 mm brush bristles and pressing the support against the surface of the contact surface while supplying a slurry in which the abrasive is dispersed in water. In the honing polishing, a slurry in which an abrasive is dispersed in water is injected under pressure from a nozzle, and the slurry is made to impinge obliquely on the surface of a support to perform a roughening treatment. Examples of the abrasive include those commonly used for polishing, such as volcanic ash, alumina, and silicon carbide. The particle size is # 200 to # 2000, preferably # 200.
400 to # 800. The support that has been mechanically roughened is immersed in an aqueous solution of acid or alkali to remove abrasives and aluminum debris that have penetrated the surface of the support, and to control the pit shape. Is preferably etched. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid, and the like, and examples of the base include sodium hydroxide, potassium hydroxide, and the like. Among these, it is preferable to use an aqueous alkali solution. When the above is immersed in an aqueous alkali solution, it is preferable to immerse the film in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid, or a mixed acid thereof to perform a neutralization treatment. When performing the electrochemical graining treatment after the neutralization treatment, it is particularly preferable to match the acid used for the neutralization treatment with the acid used for the electrochemical graining treatment. When anodizing is performed, it is particularly preferable to match the acid used for neutralization with the acid used for the anodizing.

<< Chemical surface roughening method >> The above-mentioned chemical surface roughening method is a method in which the surface is eroded by dipping in an aqueous solution of an acid or a base to roughen the surface. Sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid and the like are included, and as the base, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium tribasic sodium phosphate, tribasic potassium phosphate, silicic acid Examples include aqueous solutions of inorganic alkali salts such as sodium and potassium silicate, and aqueous solutions of organic acid salts such as sodium gluconate and sodium formate.
Among them, it is preferable to use an aqueous solution of an inorganic alkali salt, and the concentration is 1 to 50% by weight, preferably 5 to 35% by weight. The temperature is between room temperature and 90 ° C. Preferably it is 40-80 degreeC, and processing time becomes like this. Preferably it is 10 seconds or more, More preferably, it is 30 seconds or more.

<< Electrochemical Surface-Roughening Treatment >> In the above-mentioned electrochemical surface-roughening treatment, the surface roughening is generally carried out in an acidic electrolyte by using an alternating current. As the acidic electrolyte, those generally used in an electrochemical graining treatment method can be used, but a hydrochloric acid-based or nitric acid-based electrolyte is particularly preferably used. Various waveforms such as a rectangular wave, a trapezoidal wave, and a sawtooth wave can be used as a power supply waveform used for electrolysis, and a sine wave is particularly preferable. In the electrochemical surface-roughening treatment method, the entire amount of electricity required for the treatment may be continuously energized in one step, and the treatment may be performed. It can be arranged and divided into several parts. When performing the electrochemical surface-roughening treatment by dividing, the amount of positive electricity in one dividing step is 100
C / dm ² or less, and the pause time or the time during which the progress of the electrolytic treatment is slow is preferably 0.6 to 5 seconds.
Further, in the case of performing the electrochemical surface roughening treatment by dividing, it is preferable to use a hydrochloric acid-based electrolytic solution, whereby a uniform grain can be formed.

The voltage applied in the electrochemical graining treatment using a nitric acid-based electrolyte is preferably 1 to 50 V, more preferably 5 to 30 V. Current density (peak value)
Is preferably from 10 to 200 A / dm ² , and from 20 to 150 A / dm ^2.
A / dm ² is more preferred. The quantity of electricity is usually 100 to 2000 C / dm ² , preferably 2
00 to 1500 C / dm ² , more preferably 200 to 1
000 C / dm ² . The temperature is preferably from 10 to 50C, more preferably from 15 to 45C. Nitric acid concentration is 0.1
-5% by weight is preferred, and 0.5-2.0% by weight is particularly preferred. If necessary, nitrate, chloride, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid and the like can be added to the electrolytic solution. The voltage applied in the electrochemical graining treatment using a hydrochloric acid-based electrolyte is
1 to 50 V is preferable, and 5 to 30 V is more preferable. The current density (peak value) is preferably from 10 to 200 A / dm ^2, more preferably 20 to 150 A / dm ^2. The amount of electricity is 100 to 2000 C / dm ^{2 in} total for all processing steps.
Is preferable, and 200 to 1000 C / dm ² is more preferable. The temperature is preferably from 10 to 50C, more preferably from 15 to 45C. The hydrochloric acid concentration is preferably from 0.1 to 5% by weight, particularly preferably from 0.5 to 2.0% by weight. If necessary, nitrate, chloride, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid, etc. can be added to the electrolytic solution. Particularly, acetic acid is added in an amount of 0.1 to 5% by weight. Is preferred.

<< Desmut >> The support which has been subjected to the surface roughening treatment by the above-mentioned electrochemical surface roughening treatment may be treated with an acid or an alkali to remove smut (sludge) on the surface or control the pit shape. It is preferable that the surface is etched by dipping in an aqueous solution. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid, and the like, and examples of the base include sodium hydroxide, potassium hydroxide, and the like. Among these, it is preferable to use an aqueous alkali solution. As the etching amount,
1.0 to 3.0 g / weight loss including smut
m ² is particularly preferred. When the above is immersed in an aqueous alkali solution, it is preferable to immerse the film in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid, or a mixed acid thereof to perform a neutralization treatment. When the anodic oxidation treatment is performed after the neutralization treatment, it is particularly preferable to match the acid used for the neutralization with the acid used for the anodic oxidation treatment.

<Anodic Oxidation> After the surface roughening treatment, an anodic oxidation treatment is performed if necessary. The anodizing treatment is generally performed by direct current electrolysis using sulfuric acid or phosphoric acid or a mixed aqueous solution of both. A method of electrolysis at a current density of 1 to 10 A / dm ² is preferably used.
No. 2,768, a method of electrolysis at high current density in sulfuric acid, and a method of electrolysis using phosphoric acid described in U.S. Pat. No. 3,511,661. The thickness of the anodized film is preferably 0.5 to 5.0 μm, more preferably 1.5 to 3.5 μm. The density of the generated micropores is 400 to 700 cells / μ.
m ² is preferable, and 400 to 600 particles / μm ² is more preferable.

<Post-Treatment> The anodized aluminum plate may be subjected to sealing if necessary. Examples of the sealing treatment include boiling water treatment, water vapor treatment, sodium silicate treatment, dichromate aqueous solution treatment, nitrite treatment, and ammonium acetate treatment. Further, after the sealing treatment, a hydrophilic undercoat layer may be provided. As the hydrophilic undercoat layer, US Pat.
81,461, alkali metal silicate described in U.S. Pat. No. 1,860,426, hydrophilic cellulose described in U.S. Pat. No. 1,860,426, JP-A-60-49491, JP-A-63-463.
Amino acids and salts thereof described in JP-A-165183, amines having an acid group and salts thereof described in JP-A-60-232998, phosphates described in JP-A-62-19494, And a polymer compound containing a monomer unit having a sulfo group described in JP-A-10-16551.

[0047]

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

Examples 1 to 19 and Comparative Examples 1 to 3 <Preparation of Support Material> Aluminum plate having a thickness of 0.24 mm "Material # 1050, hardness H16" (Nippon Light Metal Co., Ltd.)
Were prepared by immersing each of these aluminum plates in a 1% aqueous solution of sodium hydroxide maintained at 50 ° C., and dissolving to a dissolution amount of 2.0 g / m ^2. The plate was washed with water, further immersed in 10 g / liter hydrochloric acid kept at 25 ° C. for 10 seconds, neutralized, and washed with water to obtain 22 degreased aluminum plates.

Of the 22 sheets obtained as described above, 1
Nine aluminum plates were sequentially charged with 19 types of coating solutions having varying coating / solvent weight ratios (wt%) as shown in Table 1 on an electrostatic spray gun, and the average height of the dots (μm ), Average particle size (μm) and average weight (pieces / m
m ² ) is changed as shown in Table 1 to form a dot-shaped pattern by spray coating, and a coating layer having a coated portion and an uncoated portion is provided to provide 19 types of supports of Examples 1 to 19. A body material was obtained. Also, the remaining three of the 22 degreased aluminum plates (without the dot-shaped pattern coating) were used as support materials for Comparative Examples 1 to 3 as they were.

[0050]

[Table 1]

<Preparation of Support> 19 types of support materials of Examples 1 to 19 in which the above-mentioned dot-shaped pattern coating was performed, and Comparative Examples 1 to 3 in which the above-mentioned dot-shaped pattern coating was not performed.
After performing a corrosion-resistant treatment as necessary using the support material described above, 22 types of surface-roughening treatments 1 (chemical surface-roughening treatment, electrochemical surface-roughening treatment, mechanical Of the surface roughening treatment, such as the surface roughening treatment, the type of the surface roughening treatment solution, the concentration (%), the temperature (° C.), and the dissolution amount g /
m ² ), whether or not the coating layer was removed, surface roughening treatment 2 (with or without mechanical polishing, whether or not electrochemical surface roughening treatment was performed, the type of the surface roughening treatment solution, the concentration (%), and the temperature (° C.) ) And the dissolution amount g / m ² ) of the uncoated portion, and the like, and the 19 types of roughened supports of Examples 1 to 19 and the 3 types of roughened surfaces of Comparative Examples 1 to 3 The obtained support was obtained. Anodizing treatment was performed on all of the above 22 types of supports under the same conditions.

In the anti-corrosion treatment shown in Table 2, a sol-gel reaction solution having the following composition was applied on a support material after dot-pattern coating with a bar coater, dried at 100 ° C. for 1 minute, and then subjected to corrosion resistance treatment. A coating layer was formed.

(Sol-gel reaction solution) Tetraethyl silicate 50 parts by weight Water 80 parts by weight Methanol 10 parts by weight Phosphoric acid 0.07 parts by weight Chemical surface roughening treatment in surface roughening treatment 1 in Table 2 In Table 1, the support material was immersed in a surface roughening treatment solution under the conditions shown in Table 2 until the uncoated portion reached the amount of dissolution shown in Table 2 to perform the surface roughening treatment.

In the mechanical surface roughening treatment of the surface roughening treatment 1 in Table 2, the support material was made of # 500 alumina 1
Using a 5 wt% slurry and a cylindrical rotary nylon brush, the surface was polished at 400 rpm for 30 seconds to perform a surface roughening treatment.

In the surface roughening treatments 1 and 2 in Table 2, a 50 Hz sinusoidal alternating current was used as the support material, and the current density at the peak was 40 A / dm ^2.
The surface was roughened by electrolytic etching until the dissolution amounts shown in Table 2 were obtained.

In the removal of the coating layer in Table 2, the coating layer on the support material was eluted with acetone to remove the coating layer.

In the mechanical polishing treatment in the surface roughening treatment 2 in Table 2, 15 watts of # 2000 alumina were used before the chemical surface roughening treatment or the electrochemical surface roughening treatment of the support material.
4% by using a t% slurry and a cylindrical rotating nylon brush
The surface was roughened by polishing at 00 rpm for 5 seconds.

The support material subjected to the electrochemical graining treatment in the graining treatment 2 in Table 2 was immersed in a 1% aqueous sodium hydroxide solution kept at 50 ° C. Etching was performed so that the dissolution amount including the smut of the planarized surface was 2.0 g / mm ² , then immersed in a 10% sulfuric acid aqueous solution maintained at 25 ° C. for 10 seconds, neutralized, and then washed with water. went.

Each of the above 22 types of supports (supports of Examples 1 to 19 and supports of Comparative Examples 1 to 3) obtained in this example was subjected to 20% In a sulfuric acid aqueous solution, the amount of electricity is 150 C / at a constant voltage of DC 20 V.
Anodizing treatment was performed to dm ² .

[0060]

[Table 2]

<Evaluation method> 2 obtained as described above
The maximum surface roughness (Rmax) R1 of the two kinds of supports (Examples 1 to 19 and the supports of Comparative Examples 1 to 3) and the maximum surface roughness (Rmax) of the original support material used for producing the supports (Rmax) R
max) Non-contact three-dimensional surface shape analyzer "RST"
/ PLUS "(manufactured by WYKO Co., Ltd.), observation range: 80 × 60 μm, spatial resolution: 368 × 236 pi
Table 3 shows the measured values R1, R2 and R1 / R2 = P measured under xels conditions. Also, the surface of the 22 types of supports (supports of Examples 1 to 19 and Comparative Examples 1 to 3) obtained as described above was photographed by SEM at 500 times, and the pit uniformity was good / bad. (Good / bad rough surface)
Was visually evaluated, and the results are shown in Table 3. The pits referred to here are pits of a double structure in which all the pits have an opening diameter larger than 2 μm and further include pits of 2 μm or less, and exclude pits of less than 0.1 μm. Was evaluated.

[0062]

[Table 3]

As can be seen from Table 3, the production method of the present invention can provide a support having a pit shape with an appropriate and uniform surface roughness, but the production method of the comparative example cannot provide a support having a desired surface roughness. In addition, it was found that the uniformity of the pits was poor, which was not preferable as a support for a lithographic printing plate.

[0064]

As has been demonstrated in the examples, according to the method for producing a lithographic printing plate support of the present invention, a support having an appropriate surface roughness and a uniform pit shape can be obtained at low cost. Therefore, when offset printing is performed using a lithographic printing plate obtained by applying and processing a photosensitive composition on the support, a lithographic plate excellent in water retention, excellent in printing durability and printing performance. It has excellent effects such as the ability to obtain a printing plate support.

Claims (8)

[Claims] 1. A method for producing a lithographic printing plate support, wherein the support material made of aluminum or an aluminum alloy is subjected to a surface roughening process, wherein the surface roughening process of the support material is a chemical surface roughening process. A method for producing a lithographic printing plate support, wherein the ratio of the maximum surface roughness (Rmax) before and after the surface roughening treatment of the support material is 1.2 times or more. 2. A method for producing a lithographic printing plate support, wherein the support material made of aluminum or an aluminum alloy is subjected to a surface roughening process, wherein the surface roughening process of the support material is a chemical surface roughening process. A method for producing a lithographic printing plate support, characterized in that at least at the initial stage of the surface roughening treatment, there are a portion where the treatment liquid adheres to the support material and a portion where the treatment liquid does not adhere. 3. A method for producing a lithographic printing plate support, comprising subjecting a support material made of aluminum or an aluminum alloy to a roughening treatment, wherein a coated portion and an uncoated portion are provided on the surface of the support material. A method for producing a support for a lithographic printing plate, comprising subjecting the support to a lithographic printing plate. 4. A method for producing a lithographic printing plate support, comprising subjecting a support material made of aluminum or an aluminum alloy to a surface roughening treatment, wherein after providing a coated portion and an uncoated portion on the surface of the support material, a chemical reaction is performed. A method for producing a lithographic printing plate support, comprising: performing a roughening treatment; and performing an anodic oxidation treatment with or without removing the coated portion. 5. A method for producing a lithographic printing plate support, comprising subjecting a support material made of aluminum or an aluminum alloy to a surface roughening treatment, wherein after providing a coated portion and an uncoated portion on the surface of the support material, a chemical reaction is performed. At least one kind of roughening treatment selected from mechanical roughening treatment, chemical roughening treatment, and electrochemical roughening treatment with or without removing the coated portion. A method for producing a lithographic printing plate support, comprising performing a surface treatment, and subsequently performing an anodizing treatment. 6. A method for producing a lithographic printing plate support, in which a support material made of aluminum or an aluminum alloy is subjected to a surface roughening treatment, the method comprising: providing a coated portion and an uncoated portion on the surface of the support material; Perform chemical surface roughening,
Further, with or without removing the coating portion, at least one type of surface roughening treatment selected from mechanical surface roughening treatment, chemical surface roughening treatment, and electrochemical surface roughening treatment is performed. A method for producing a lithographic printing plate support, comprising performing an anodizing treatment. 7. A method for producing a lithographic printing plate support, wherein a support material made of aluminum or an aluminum alloy is subjected to surface roughening treatment, after providing a coated portion and an uncoated portion on the surface of the support material. Performing a treatment for imparting corrosion resistance to the non-coated portion, and further removing or not removing the coated portion, mechanical roughening treatment, chemical roughening treatment,
A method for producing a lithographic printing plate support, comprising performing at least one kind of surface-roughening treatment selected from electrochemical surface-roughening treatment, followed by anodizing treatment. 8. The method of providing a coating portion on the surface of a support material made of aluminum or an aluminum alloy is at least one method selected from a method using a spray gun, an ink jet method, and a printing method. Item 8. The method for producing a lithographic printing plate support according to any one of Items 3 to 7.