JPS59225998A - Manufacture of base for planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain a base for a planographic printing plate free from contamination of non-image parts or ground contamination while retaining durability to printing, by a method wherein an aluminum plate is sanded, is then subjected to anodic oxidation, and is treated in a specified solution. CONSTITUTION:The aluminum plate used as a blank material of the base for the planographic printing plate is subjected to sanding, and then to anodic oxidation. The aluminum plate is then treated in a diluted aqueous solution of a salt of a divalent metal and phytic acid or a salt thereof at a temperature of 60- 100 deg.C. The aluminum plate thus treated is washed with water to remove excess treating solution, is dried, and then a photosensitive layer is provided thereon by coating. A photosensitive composition for constituting the photosenstive layer preferably comprises o-quinonediazide compound. A photosensitive planographic printing plate thus manufactured has high adhesive strength between the aluminum plate as the base and the photosensitive layer provided thereon, has excellent durability to printing, and a printed matter obtained thereby is completely free from ground contamination.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a support for a lithographic printing plate, and more particularly to a method for manufacturing a support for a lithographic printing plate having an anodized film.

Lithographic printing plates are a sophisticated printing method that takes advantage of the fact that water and oil do not mix. The surface of aluminum, which is widely used as a support, is usually electrochemically or mechanically grained to give it a satin-like rough surface. This grained aluminum support is etched with a solution such as an acid or alkali, and then anodized, and if necessary, subjected to a hydrophilic treatment, and then a photosensitive layer is provided. In this way we get f
When printing using photosensitive lithographic printing plates, substances contained in the printing process, especially dyes or pigments added to identify image areas, are irreversibly adsorbed and contaminate non-image areas, so correction is not required. During the process, it may be difficult to distinguish between image areas and non-image areas, marks of correction may be clearly left on the printing plate, and if the level of contamination increases, so-called smudging may occur during printing.
It had a deletion A(]l- which made it unusable as a printing plate.

In order to improve such defects, conventionally, anodizing treatment 1. U.S. Pat. No. 3,/ri,
Immersion treatment in alkali metal silicate as described in US Pat. No. 3, lt'A
A method of immersion treatment in an aqueous solution of an alkali metal salt of fluorinated zirconium acid as described in U.S. Pat. No. 0,030, or US Pat. No. 3,160. ≠2 by the method of providing an undercoat layer of hydrophilic cellulose containing a water-soluble metal salt as described in Specification 4 of the above-mentioned 1. Preventing contamination of non-image areas (2) It is possible to prevent background stains from occurring on printed matter, but on the other hand, the printing durability of the printing plate is ≠ 0 to 10% of that without the above treatment. (A new problem arises in that it decreases by 1.

In addition, in order to improve the above-mentioned drawbacks caused by the presence of the anodic acid arsenic film, JP-A No. 12-12g-53 and JP-A No. 31-. A method of anodic oxidation under specific conditions has been proposed as disclosed in each publication of No. 21≠00. However, in these methods, the aluminum ion concentration in the electrolyte that forms the anodic oxide film is -@to-,2
It is written as 39/l.

Since the method involves raising the temperature to a higher temperature or performing anodic oxidation in a mixed electrolyte of sulfuric acid and cynic acid, scale is likely to occur and a large amount of sludge (aluminum hydroxide) is produced when treating the P1 waste liquid. In addition, it requires a lot of effort to control the acid concentrations of both sulfuric acid and phosphorous alcohol, resulting in poor manufacturing suitability. Furthermore, when anodized at high current density, the film becomes noticeably 1. <
It has the disadvantage that a non-uniform anodic oxide film, so-called "1 burn", is formed which grows.

Furthermore, due to the low acid concentration in the electrolyte, the formation of

Since the porosity of the anodic oxide film was significantly reduced, the adhesion with the photosensitive layer was insufficient and the printing durability was reduced to 0% to 0%.

Therefore, an object of the present invention is to provide a support for a lithographic printing plate that does not cause staining or scumming in non-image areas without reducing printing durability.

Still another object of the present invention is to provide a support for a lithographic printing plate that has improved abrasion resistance.

The inventors of the present invention have made the present invention as a result of intensive studies. This is a method for producing a support for a lithographic printing plate, characterized in that the process is carried out in a water bath at a temperature of 600 to 100 degrees Celsius.

The present invention will be explained in detail below.

The aluminum plate used in the present invention is a plate-shaped body made of pure aluminum whose main component is aluminum or an aluminum alloy containing a trace amount of foreign atoms. These foreign atoms include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, titanium, etc., and the alloy composition has a content of at most 1O7J mass % under brightness. The aluminum 11 suitable for the present invention is pure aluminum, but since completely pure aluminum is difficult to produce due to smelting technology, it is preferable to use aluminum that does not contain foreign atoms as much as possible. Further, if the aluminum alloy has the above-mentioned content, it can be said that the aluminum alloy can be applied to the present invention. As described above, the composition of the aluminum plate to be applied to the present invention is not limited; conventionally known and publicly used aluminum plates can be used as appropriate.

The thickness of the aluminum plate used in the present invention is as follows:
Approximately o, imm to o-zmm is preferable.

The above aluminum plate is subjected to graining treatment.

Prior to this graining treatment, a degreasing treatment using a surfactant or an alkaline aqueous solution may be performed to remove rolling oil from the surface of the aluminum plate.

As the graining method, a method of mechanically roughening the surface, a method of electrochemically dissolving the surface, and a method of selectively dissolving the surface chemically are used.

As a method for mechanically roughening the surface, known methods such as one-ball polishing method, brush polishing method, blast polishing method, Nokhu polishing method, liquid honing method, etc. can be used. Further, as an electrochemical surface roughening method, a method can be used in which alternating current or direct current is used in an electrolytic solution such as hydrochloric acid, nitric acid, or a mixture thereof.

-! However, various surface roughening methods such as the Kinuso Zetrap method can also be used, as disclosed in Publication No. J02.

The aluminum plate thus roughened is subjected to alkali etching treatment and neutralization treatment as required.

The aluminum plate thus treated is anodized.

The electrolyte used is sulfuric acid, phosphoric acid, oxalic acid, chlorinated acid, or a special mixed acid.

The electrolyte Qfa degree is determined as appropriate depending on the type of negative 1R solution.

The treatment conditions for anodic oxidation vary depending on the electrolyte used;
It is suitable if the liquid flow rate of the 0 weight % solution is in the range of 1-700 CX %, the flow density 5-60 A/dm, 1 voltage 1-1 ocrV electrolysis time/Q seconds - jO minutes.

+i1 city of anodized film, 0. /~109/m2 is preferable, but more preferably [,,< is in the range of 7~6g7m. The aluminum plate that has undergone anodization treatment in this way is treated with a divalent metal salt and phytic acid or its salt in a dilute water bath solution. inside to 0υ
~) 00°.

Particularly useful divalent gold salts for use in the present invention are water-soluble salts of zinc, nickel, cobalt, magnesilanochloride, barium, strontium, manganese, tin, etc., and salts formed with mineral or organic acids. Salt is preferred.

Particularly preferred are carbonic acid, hydrochloric acid, sulfuric acid, nitric acid,
These are the divalent metal salts of cynic acid, oxalic acid, organic carbonic acid, organic nulphonic acid, and organic phosphonic acid. Among these, the covalent metal salts of carboxylic acids such as acetic acid, salicylic acid, benzoic acid, thiobenzoic acid, gluconic acid and lactic acid are more preferred.

rtq can be used alone or in combination on two tJVs.
can do. The preferred content of the monovalent metal salt of fL et al. in the treatment solution is 0.007 to 2% by weight, more preferably 0.0% to 2% by weight, Δ゛% by weight. 1 of these
Phytic acid or its salts used with valent metal salts (
The amount of sodium salt, potassium salt, lithium salt, ammonium salt, etc.) added is 0°00IN1% by weight, and more preferably 0.01 to 3% by weight. In some cases, a complex obtained by subjecting these monovalent metal salts to a caulking reaction with phytic acid or its salt Kl may be used.

The aluminum plate having the anodic oxide film is treated in a treatment solution containing these monovalent metal salts and phytic acid or its salt at a temperature of 60 to 1000 (:) for approximately λ seconds to j minutes. Preferably, the treatment can be carried out by a known method, such as a dipping method.

The treated aluminum plate is washed with water to remove excess treatment solution [6. After drying, a photosensitive layer is applied and removed.

The photosensitive composition constituting the photosensitive layer is one whose solubility or swelling property in a developing solution changes before and after exposure, such as a composition comprising an 0-quinonediazide compound,
A composition consisting of a diazo resin, a composition consisting of a photosensitive AND compound, -C)1=4;)1- to O- in the main chain or side chain
Compositions made of polymer compounds containing groups and photopolymerizable compositions made of addition-polymerizable unsaturated compounds can be used in the present invention, and photosensitive compositions made of 0-quinonediazide compounds are particularly preferred.

The 0-quinonediazide compound is a compound having at least seven 0-quinonediazide groups, and its solubility changes upon irradiation with actinic rays. Regarding this 0-quinonediazide compound, please refer to Jar Omba Kosar's 7.
gh t-8ens it i ve System
s:(:hemistry and Applica
tion of Nonsilver Halide
Photographic Processes” (
John Wiley & 5ons.

Inc, l No. 33 ~ 3! , page 2, and these are all compounds that can be applied for the purpose of the present invention. In particular, sulfonic acid esters or sulfonamides of O-quinonediazide reacted with various aromatic polyhydroxylated compounds or amines are suitable. And Tokuko Akihiro 3-. Benzoquinone-/ described in Publication No. 21≠03.

Esters of cordiazide sulfonic acid chloride and polyhydroxyphenyl or naphthoquinone-1.

Esters of λ-diazide sulfonic acid chloride and pyrogallol-acetone resin are most preferred. Other relatively suitable O-quinonediazide compounds and 1. U.S. Patent Nos. 3.0 and 120 and 3.7gg.
There are esters of benzoquinone-11, 2-diazide sulfonic acid chloride or nandoquinone-/2-diazide sulfonic acid chloride and phenol formaldehyde resin, which are described in the specifications of No. 1, No. 210.

The 0-quinonediazide compound alone constitutes the photosensitive layer, but a resin soluble in alkaline water is combined with the binder ()zeta inder 1 and 1. Used with lever type resins.

Examples of resins soluble in alkaline water include novolac resins having this property, such as phenol formaldehyde 1M resin, cresol formaldehyde resin,
pt-butylphenol-formaldehyde resin, phenol-modified xylene resin, phenol-modified xylene resin
Methylene/ethylene resin, etc. Other useful alkaline water-soluble resins include polyhydroxystyrene, borino 1
Examples include 0-glycanated hydroxystyrene and copolymers of (meth)acrylic acid and other vinyl compounds.

, the amount of O-quinonediazide compound in the adhesive consisting of O-quinonediazide compound and resin soluble in alkaline water is within the range of 10% by weight, totaling 20,410＠箭The amount ratio is about %. Furthermore, it is preferable to add a dye or pigment as an image coloring agent to the composition comprising the O-quinonediazide complex.

Sensitivity again? A cyclic acid anhydride or other desired bulking agent (filler) can be added as appropriate in the first step of increasing the volume.

The coating liquid for forming the photosensitive layer contains the above components,
For example, λ-methoxyethanol, λ-ethoxyethanol, λ-methoxyethyl acetate, coethoxyethyl acetate, dimethylformamide, methanol,
Ethanol, n-propertool, i-propertool, methylene chloride, ethylene dichloride, trichloroethane, monochlorobenzene, toluene, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate , vinegar rll
Dissolve it in organic solvents such as n-butyl, esters such as methyl amyl acetate, or a mixed solvent thereof! i! Made by I. The amount ratio of solid components in the coating liquid is approximately 0. /~about 2-t' [4iii%, preferably/~)! It may be about % by weight.

The prepared coating solution is treated as described above by various coating means such as doctor coating, roller coating, gravure coating, bead coating, and dip coating.
,, applied onto an aluminum plate. The drying of the coating liquid layer can also be done by applying conventional techniques.
Dry in an atmosphere of K. The sensitive layer after drying is about O
The amount is about 17 to 79/rn2, and 0.5-≠g/m' is a more preferable amount.

The thus obtained Il & original lithographic printing plate was imagewise exposed to a light source containing actinic rays for 0-quinonediazide compounds such as carbon arc lamps, xenon lamps, mercury lamps, tungsten lamps, and metal halide lamps.
When developed, it becomes a planographic print A1111 plate.

The photosensitive lithographic printing plate according to the present invention has high adhesion strength between the aluminum plate that is the support and the photosensitive layer provided thereon, has excellent printing durability, and has no "background stain" on the printed matter. It is an extremely useful printing plate because it has the excellent performance of not causing any problems.

Further, the manufacturing method of the present invention is industrially advantageous because it is simple in terms of equipment and operation, and can be carried out at low cost.

Next, the present invention will be specifically explained based on examples. Note that % indicates weight % unless otherwise specified.

Example 1 /S aluminum plate with thickness O1λ4tmm is l004-
7θ% aqueous solution of tertiary sodium phosphate maintained at
The aluminum plate was immersed for 6'1'' to degrease it, then grained with a nylon brush (desmutted with a 3% aqueous solution of sodium aluminate at 3z to 0c).The aluminum plate was then electrolytically roughened in dilute nitric acid for 20 minutes. 2A/dm in % sulfuric acid
In the air, the flow density is λ for λ minutes, then 70°
(:acetic acid Di!, t'F,) ', treated with an aqueous solution consisting of J% and phytic acid/% for 10 seconds, and then thoroughly washed with running water.

Next, apply sensitive YC liquid to this aluminum coating.
An 11th plate of sensitive lithographic printing of / m2 was obtained.

Rice ts! r? M No. 3.6 J r, i,
Naphthoquinone/2-diazide!-sulfone of polyhydroxyfuconyl obtained by condensation of acetone and pyrogallol described in Example 1 of Specification No. 702 Acid ester Cresol formalde 2.0M 11 parts Human resin Tetrahydrophthalic anhydride', Mft part Oil blue@to3 o, 03 parts by weight (manufactured by Orient Chemical Industry ■) Naphthoquinone-7,2-diazide-≠-sulfonic acid chloride 0. 0! parts by weight λ-methoxyethyl acetate, 20 parts tate methyl ethyl ketone' 20 parts by weight 43 parts The transparency was passed through the thus obtained photosensitive flat IMf printing plate from a distance of 3 K W from a distance of /TrL. The exposed photosensitive lithographic printing plate was exposed to a sodium silicate water bath solution (Si
(J □ sweetened xi%, Na2U content 1% by weight) 3
32g, IAI% potassium hydroxide aqueous solution i9i, 3t%
To the hair alkyl, add 2 g of IN-dihydroxyethylbetaine amphoteric surfactant aqueous solution and 6 J of pure water to a developer diluted 7 times with water.
1' and developed for 40 seconds. After rinsing with water, a protective gum made of hydrophilic colloid was applied, and the product was mounted on a printing machine and printed, resulting in beautiful printed matter with no stains in the non-image areas.

Example 2 The anodized aluminum plate of Example 1 (5) was anodized at 70° in cobalt acetate 0.3% and phytic acid/% or Δ Hakuba bath solution.
After processing for 10 seconds, washing with water and applying a photosensitive layer of rush f! Anodized aluminum plates treated with a 1% acetic acid cobaphytic acid alone water bath solution showed that the phytic acid was removed by running water when washed with water. However, the photosensitive lithographic printing plate developed with a liquid solution and treated with a mixed aqueous solution of cobalt acetate and phytic acid had fatigue 1. Even when the liquid was used, no stains were observed in the non-image area during printing.

Example 3 Although nickel acetate or nickel sulfate was used in place of cobalt acetate in Example 2, the same results as in Example 2 were obtained.

Claims (1)

[Claims] l After graining and anodizing an aluminum plate,
A method for producing a support for a lithographic printing plate, characterized in that it is treated in a dilute aqueous solution of a divalent metal salt and phytic acid or a salt thereof at a temperature of 100'U.2. After standing, anodizing, and then anodizing in a dilute aqueous solution of a divalent metal salt and phytic acid or its salt,
00 (processed at a temperature of 100"L:) 7. A method for producing a photosensitive lithographic printing plate, characterized in that the photosensitive layer is then provided. 3. The photosensitive layer is made of an 0-quinonediazide compound. The photosensitive lithographic printing plate according to claim 2, characterized in that: