JPS59220395A - Aluminum alloy base for base for planographic printing plate and said base - Google Patents

Abstract

PURPOSE:To obtain an excellent rate of dissolution in a chemical etching treatment and produce pits in a uniformly crowded condition, by incorporating specified amounts of Mg and Si, or further incorporating at least one of the specified amounts of Mn and Cr, into an Al alloy plate. CONSTITUTION:The Al alloy plate for a planographic printing plate comprises 0.30-1.5wt% of Mg and 0.15-0.80wt% of Si, or further comprises at least one of 0.05-0.30wt% of Mn and 0.05-0.30wt% of Cr. The plate is so conditioned that the size of particles of intermetallic compounds distributed therein becomes 0.1-2mum.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support for a lithographic printing plate, particularly an aluminum alloy plate for a lithographic printing plate support.

Generally, when an aluminum plate is used as a printing plate support, its surface is usually roughened in order to improve the adhesion between the photosensitive film and the aluminum plate and to improve water retention in non-image areas. It is. This surface roughening treatment is
Mechanical graining (so-called graining) such as boulderaine, sandsilast, and brushdalene, electrochemical graining (also called electrolytic polishing), and chemical etching (chemical graining) are known. Each of these conventional graining methods has advantages and disadvantages. Generally, mechanical graining methods have problems such as scratches, dirt, and residual abrasives.

The electrochemical graining method can change the depth and shape of the grain to some extent depending on the amount of electricity, but generally a large amount of electricity is required to create grain suitable for lithographic printing plates, making it expensive. It has the disadvantage of being time consuming.

On the other hand, chemical dulling grains aluminum and aluminum alloys through a chemical etching reaction using an acid or alkali etchant, so the process is simple and suitable for continuous strip treatment, especially for double-sided treatment. It is industrially advantageous for making printed plates. However, it has been difficult to manufacture high-quality printing plates using commercially available aluminum or its alloys. The surface roughness and uniform pit pattern (the diameter of the etching pits are uniform and the depth of the peaks and valleys are uniform) are required to satisfy the sufficient printing durability and stain resistance required for printing plates. This is because it is difficult to prepare a surface with both of the following properties using conventional chemical etching methods. According to experiments conducted by the present inventors, commercially available aluminum and aluminum alloy materials JIS1
050.1100 and 3003 materials were chemically etched with various etchants, resulting in a practical surface roughness of 0.3 to 1.2 μR, which is preferable for printing plates.
It is difficult to obtain α (center line average roughness), and even if the equivalent roughness is changed, the reaction rate is slow and processing time is slow, or the etchant contains components harmful to the human body, causing problems during work. Various problems have been experienced, such as the etching cost being high and not suitable for practical use.

The present invention relates to an aluminum alloy plate for a lithographic printing plate support that can improve these drawbacks, and a lithographic printing plate support using the same. The aluminum alloy plate of the present invention exhibits an excellent dissolution rate when subjected to chemical etching treatment, and contains an intermetallic compound that promotes uniform pit formation. It is possible to form a focal point distributed over

That is, in the present invention, Mg is 0.30 to 1.5 (by weight)
% and 0.15 to 0.80% of Si, or further contains 0.05 to 0.30% of M3 and 0.05 to 0.30% of Si.
% of aluminum alloy plate for lithographic printing plates, and a support for lithographic printing plates obtained by roughening or roughening and anodizing the surface of this alloy plate. It is the body.

The alloy composition based on the present invention will be explained below.

The alloy plate of the present invention has a My content of 0.30 to 1.50%.

Si 0.15-0.80% and 0.0% as necessary
Contains 5-0.30% Or or Mn. When producing an aluminum alloy plate for a lithographic printing plate support, an alloy formed into an ingot by a conventional method is hot-rolled and cold-rolled, then quenched at 500C or higher, and then tempered. BJy and number 8 are M
It precipitates as a 128i intermetallic compound. The conditions for this heat treatment are selected depending on the surface roughness of the pit pattern generated by the etching treatment. In order to obtain the most suitable roughness as a support for a lithographic printing plate, it is desirable to adjust the size of the intermetallic compound precipitated to 0.1 to 2 μm.

In tempering treatment for precipitation, 200-400C,
Preferably, heat treatment is performed at 250 to 350C for 30 minutes or more. A final cold working is then carried out to obtain the strength required as a printing plate support.

Mf& and Or are intermetallic compounds M! Added to obtain uniform precipitation of 12Si. My and Or are My 2 E3
It has almost the same effect on the uniform precipitation of i, but the effect is small when the amount added is less than 0.05%, and 0.30%
M! This is not preferable because it produces intermetallic compounds other than 12Si and impairs solubility.

M y 2 S * precipitated by the tempering treatment is GP
It takes various forms such as zone, β'', β', and β, and its solubility in acids differs depending on the form. Generally, β' is more soluble.

Precipitated intermetallic compound M! Since I2Si has a higher solubility in acids than the matrix, when the alloy sheet according to the present invention is treated with nitric acid, sulfuric acid, phosphoric acid, or a mixed acid thereof, Mg2Si is selectively dissolved, forming uniform pits on the surface of the sheet. Form and produce a rough surface.

The opening diameter of the pit and the surface roughness of the rough surface are M! It varies depending on the etching conditions (liquid composition, temperature, time) as well as the precipitation form and distribution of 12Si.

The lithographic printing plate support of the present invention can be obtained by chemically roughening the surface of the aluminum alloy plate of the present invention by acid treatment as described above. The alloy surface may be subjected to conventional chemical roughening using an alkali, or mechanical roughening using Ballgrain, Sand 9 blast durrene, brushing durrene, or the like.

The aluminum alloy plate treated as described above can be used as it is as a lithographic printing plate support, but it can be further provided with an anodized film and used as a higher quality lithographic printing plate support.

For the anodic oxidation treatment, methods conventionally used in this field can be used. Specifically, an anodic oxide film can be formed on the surface of an aluminum support by passing a direct or alternating current through aluminum in an aqueous solution of sulfuric acid, phosphoric acid, oxalic acid, or a combination of two or more of these.

The conditions for anodic oxidation vary depending on the electrolyte used and cannot be determined unconditionally, but in general, the electrolyte concentration is 1 to 80% by weight, the liquid temperature is 5 to 70C, and the current density is 0. .5~60 ampere/m2, 'voltage l~100V
, an electrolysis time range of 10 to 100 seconds is appropriate.

Among these anodic oxide films, especially British Patent Nos. 1 and 4
No. 12,768, the method of anodizing at high current density in sulfuric acid, and the method of electrolytic phosphoric acid oxidation described in U.S. Pat. No. 3,511,661. A method of anodizing as a liquid is preferred.

The anodized aluminum plate is further described in U.S. Pat.
As described in U.S. Pat. As described in the '426 specification, a subbing layer of a hydrophilic cellulose (e.g. carboxymethylcellulose) containing a water-soluble metal salt (e.g. zinc acetate) can also be provided.

A conventionally known photosensitive layer can be provided on the support for a lithographic printing plate according to the present invention to obtain a photosensitive lithographic printing plate, and the lithographic printing plate obtained by plate-making processing the same: It has excellent sexual characteristics.

The composition of the above-mentioned photosensitive layer includes the following.

■ Photosensitive layer consisting of diazo resin and binder U.S. Pat. No. 2,063,631 and U.S. Pat.
Publication No. 49-45323, British Patent Nos. 1 and 3
12,925 and 1.023,589 are preferred, and the binder is
British Patent No. 1,350,521, British Patent No. 1,460,9
No. 78 specifications, U.S. Patent No. 4,123,276,
Preferably, No2 Ingu is described in the specifications of the same No. 3,751,257, the same No. 3,660,097, and Japanese Patent Application Laid-open No. 54-98''614.

(2) Photosensitive layer consisting of an O-quinonediazide compound A particularly preferred O-quinonediazide compound is an O-naphthoquinonediazide compound, for example, U.S. Pat. No. 2,766,
No. 118, No. 2,767,092, No. 2,772
, No. 972, No. 2,859,112, No. 2,90
No. 7,665, No. 3,046,110, No. 3.0
No. 46,111, No. 3,046,115, No. 3,
No. 046,118, No. 3.046,119, No. 3
, 046,120, 3,046,121, 3,046,122, 3,046,123, 3,061,430, 3,102,809 ,
It is described in numerous publications including the specifications of the same No. 3,106,465, the same No. 3,635,709, and the same No. 3,647,443, and these are preferably used. I can do it.

■ Photosensitive layer consisting of an azide compound and a binder (polymer compound) For example, British Patent No. 1,235,281, British Patent No. 1.4
Specifications of No. 95,861 and JP-A No. 51-32331
In addition to the compositions comprising an azide compound and a water-soluble or alkali-soluble polymer compound described in JP-A No. 50-5102 and JP-A-51-36128, etc.
No. 0-84302, No. 50-84303, No. 53-1
2984, etc., compositions consisting of a polymer containing an r group and a polymer compound as a binder are included.

■Other photosensitive resin layers For example, polyester compounds disclosed in JP-A No. 52-96696, British Patent No. 1.112,277,
Polyvinyl cinnamate resins described in U.S. Patent Nos. 1,313,390, 1.341,004, and 1,377,747;
The photopolymerizable photopolymer compositions described in the specifications of No. 27 and No. 4,072,528 are included.

The amount of photosensitive layer provided on the support is about o,i~71I
/rrL2, preferably in the range of 0.5 to 4117 m.

After the photosensitive lithographic printing plate is imagewise exposed, a resin image is formed by performing processing including development by a conventional method. For example, in the case of a lithographic printing plate having the photosensitive layer (1) made of a diazo resin and a binder, after image exposure, the unexposed portions of the photosensitive layer are removed by development to obtain a lithographic printing plate. In the case of a lithographic printing plate having a photosensitive layer (2), after image exposure, the exposed portion is removed by development with an alkaline aqueous solution to obtain a lithographic printing plate.

Hereinafter, the effects of the alloy for planographic printing plate supports according to the present invention will be explained in detail based on the following examples.

Example 1 Six types of aluminum alloy plates shown in Table 1 were manufactured and immersed for 4 minutes at 90p in an etching solution containing 30011L of nitric acid and 110W of phosphoric acid in 1 part of water, and then the weight loss, surface roughness and Scanning electron microscope (SEM)
) was used to observe pit patterns.

Table 1 Alloy composition Table 2 Chemical graining performance Alloy A with My and SL as main components as shown in Table 2
Samples Nos. 1 to 5 had a fast dissolution rate, and a rough surface with surface roughness of 0.35 μm or more and uniform pits of 0.5 to 3 μm was obtained. The addition of MrL and Or made the pit/groove turns uniform.

Example 2 Samples of JFLl and Mu5 in Example 1 and samples of Comparative Example were placed in an electrolytic solution containing 20% sulfuric acid as a main component at a bath temperature of 3.
An oxide film of a 17 m 2 was applied at 0C.

Next, it was immersed in a 2.5% aqueous solution of sodium silicate No. 60C and treated with 60C for 11 minutes, thoroughly washed with water, and then dried.

Samples (5) and (c) were prepared by matching the samples of AI, A5 and comparative example to the supports thus obtained.
, 0. The following solution (I) was applied to each sample prepared in this manner so that the coating weight after drying was 2.0.9. A lithographic printing plate was prepared so that the difference was Δ2.

The thus obtained photosensitive planographic printing plate was heated with a 3KW metal halide lamp for 177cm. After exposing for 70 seconds from a distance of
(c), I got 0.

Sodium sulfite 3.9 Benzyl alcohol 309 Triethanolamine 21 Monoethanolamine 59 Next, printing was carried out according to the conventional procedure, and the results shown in Table 3 were obtained.

Table 3 Example 3 The aluminum alloy plates of Example 1 and Comparative Example 1 were treated in a suspension of pumice stone and water using a rotating nylon scrubber, and then treated with a 20% aqueous solution of caustic soda. Etching was carried out so that the amount of dissolved aluminum was 817 m2. After thoroughly washing with running water, pickling was carried out with a 25% nitric acid aqueous solution and washing with water to prepare a substrate.

The substrate prepared in this way was subjected to a chemical dulling treatment using the method described in Example 1, washed with water, and then anodized and hydrophilized using the method described in Example 2 to obtain a support sample O). ) and (E) were created.

The support thus obtained 0. (g) The photosensitive layer of Example 2 was provided so that the dry coating amount was 2.09/m2.

The photosensitive lithographic printing plate thus obtained was exposed to light for 70 seconds from a distance of 1.5 in. with a 3KH metal halide lamp, immersed in the developer shown in Example 2 for 1 minute at room temperature, and then lightly rubbed on the surface with absorbent cotton to remove the unexposed areas. Removed and lithographic printing plate @
(G) was obtained. Next, printing was carried out according to a conventional procedure, and the results shown in Table 4 were obtained.

Table 4 Example 4 Example 1 The aluminum alloy plates of Mu 2 in Table 1 and Comparative Example 1 were chemically dained at 60C in 10% NaOH for 2 minutes. These substrates were thoroughly washed with running water, pickled with a 25% nitric acid aqueous solution, and washed with water to prepare substrates.

The substrate prepared in this way was subjected to a chemical daining treatment using the method described in Example 1, washed with water, and then anodized and hydrophilized using the method described in Example 2 to obtain a support sample (triple). ), 0 was created.

The photosensitive layer of Example 2 was provided on the supports (G) and (G) thus obtained so that the coating area when dried was 2.0117 m 2 .

The photosensitive lithographic printing plate thus obtained was exposed for 70 seconds to a 3KW metal halide 9 lamp from a distance of 1rIL.
After being immersed in the developer shown in Example 2 at room temperature for 1 minute, the surface was lightly rubbed with absorbent cotton to remove the unexposed areas, thereby obtaining lithographic printing plates 00.

Next, printing was carried out according to a conventional procedure, and the results shown in Table 5 were obtained.

Table 5 Procedural amendment June 2, 1981 Patent Application No. 93998 2, Title of invention Aluminum support for lithographic printing plate support and Support for lithographic printing plate 3, Person making the amendment Relationship: Patent applicant name (520) Fuji Photo Film Co., Ltd. (
75-) Kasumigaseki Building Post Office P.O. Box 49
issue

Claims (8)

[Claims] (1) 0.30 to 1.5 (weight)% My and 0 Si
．． Contains 15-0.80% or further contains 0.05-0.05%
An aluminum alloy plate for lithographic printing plates, characterized in that it contains at least one of 0.30% Mn and 0.05 to 0.30% Cjr. (2) The aluminum alloy plate for lithographic printing plates according to claim (1), wherein the size of the intermetallic compound distributed in the aluminum alloy plate is adjusted to be 0.1 to 2 microns. . (3) Contains 0.30 to 1.5% (by weight) of My and 0.15 to 0.80% of E3i, or further contains 0.05% of E3i.
~0.30% (DMn and 0.05-0.30% Cjr
1. A support for a lithographic printing plate, comprising an aluminum alloy plate having a roughened surface. (4) The support for a lithographic printing plate according to claim (3), wherein the surface roughening is carried out by chemical roughening with an acid. (5) The support for a lithographic printing plate according to claim (3), wherein the surface roughening is performed by mechanical roughening and further chemical roughening using an acid. (6) The support for a lithographic printing plate according to claim (3), wherein the surface roughening is carried out by chemical roughening with an alkali and further chemical roughening with an acid. (7) The lithographic printing plate support according to any one of claims (4) to (6), which is subjected to surface roughening &iK anodization. (8) Any of claims (4) to (7), wherein the size of the intermetallic compound distributed in the aluminum alloy plate is adjusted to be 0.1 to 2 microdays. The lithographic printing plate support described in the above item.