JPS6330294A - Aluminum alloy support for planographic printing plate and its preparation - Google Patents

Abstract

PURPOSE:To provide a support for an aluminum alloy planographic printing plate fitted to electrochemical surface roughening treatment and having excellent strength and printability, by incorporating Mg, Fe, Ni and Ti as essential components in specific quantity. CONSTITUTION:A support for a planographic printing plate is prepared by a method wherein an aluminum alloy containing 0.30-3% of Mg, 0.15-0.50% of Fe, 0.005-0.30% of Ni and 0.01-0.10% of Ti as essential components and further containing Si, Cu and Mn respectively in quantity of 0.20% or less and other metal components respectively in quantity of 0.010% or less as impurities and comprising the remainder of Al is cast and subjected to homogenizing heat-treatment, hot rolling, cold rolling and process annealing and further subjected to finish cold rolling of a thickness reducing ratio of 30% or more. Mg enhances strength without exerting adverse effect on the surface roughening treatment of the support and printability and Fe enhances fatique resistant strength. Ni has a finely and uniformly precipitating property in Al in the form of an Al3Ni compound and Ti is added in order to finely pulverize the crystal particles of a cast ingot.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an aluminum alloy support used for lithographic printing plates, and is particularly suitable for electrochemical roughening treatment, and This invention relates to an aluminum alloy lithographic printing plate support that has excellent strength and printability.

[Prior Art] Conventionally, what has been widely used as a lithographic printing plate is the so-called PS, which is made by coating a photosensitive substance on an aluminum plate that has been subjected to surface treatments such as roughening treatment and anodizing treatment, and then drying the plate.
A printing plate obtained by subjecting a plate to plate-making processes such as image exposure, development, and camming. The undissolved photosensitive layer resulting from this development process forms an image area, and the exposed aluminum surface underneath when the photosensitive layer is removed becomes a water receiving area because it is made of hydrophilic material, and often forms a non-image area. It is a known fact.

As a support for such a lithographic printing plate, an aluminum plate is generally used, which is lightweight and has excellent surface treatment properties, workability, and corrosion resistance. Conventional materials used for this purpose include IIS
A 1050 (△1 alloy with purity of 99.5% by weight or more), JIS A 1100 (A I-〇, 05~
o, 2o11%Cu alloy), JIS A 3003
(A I -0,0!i ~ (1,20 wt%Cu-1
There are aluminum alloy plates with a thickness of 0.1 to 0.8 mm, such as aluminum alloys such as aluminum alloys, such as aluminum alloys, such as aluminum alloys, such as aluminum alloys, such as aluminum alloys, such as aluminum alloys having a thickness of 0.1 to 0.8 mm. The surface is roughened through a process that combines the above steps, and then anodized.

Specifically, an aluminum lithographic printing plate that has undergone mechanical roughening treatment, chemical etching treatment, and anodic oxide film treatment described in JP-A-48-49501 @, or JP-A-51-61304 Aluminum lithographic printing plates were sequentially subjected to the chemical etching treatment and anodized film treatment described in JP-A-54-146234, and the aluminum planographic printing plates were subjected to the electrochemical treatment described in JP-A No. 146234/1984, followed immediately by the anodized film treatment. Aluminum lithographic printing plate, Special Publication Showa 4L-2812
The electrochemical treatment, chemical etching treatment, and anodic oxidation film treatment described in No.
Aluminum lithographic printing plates and the like which are subjected to the treatment described in No. 8-28123 are known.

By providing a suitable photosensitive layer on this support, it is possible to produce up to 100,000 sheets of clear printed matter.

[Problems that the invention attempts to solve] Today, as printing speeds have increased with the advancement of printing technology, the stress applied to printing plates, which are mechanically fixed to both ends of the printing press cylinder, has increased. If the strength is insufficient, this fixed part may become deformed or damaged, causing damage such as plate cracking, or the plate may break due to repeated stress on the folded part of the printing plate (gripping), making printing impossible. It often happens.

On the other hand, conventional JIS A 105[1)' aluminum alloy plate (51 electrochemical roughening treatment (JJ3) gives uniform roughness or appropriate surface roughness to the surface during printing. It is difficult to stain the non-image areas, but since the strength of the printing plate is low, it is easily deformed and the plate is likely to crack.

On the other hand, JIS A 3003 aluminum alloy plates have sufficient 4T strength, but electrochemical roughening treatment does not provide a uniform or appropriate surface roughness, and it also tends to cause stains in non-image areas during printing. There were drawbacks.

The present invention has higher strength as a printing plate than conventional materials, and can obtain a uniform rough surface and appropriate surface roughness through surface roughening treatment, especially electrochemical roughening treatment, and can eliminate non-image areas during printing. The present invention provides an aluminum alloy support that is resistant to staining and plate cracking.

[Means for solving the problems] The lithographic printing plate support of the present invention has an M g of 0.30 to 3.
%, [eO, 15-0.50%, Ni01005-0.
5iSCu containing 30%, -[' i (1, (11-0, 10%) as essential components and 0620% or less as impurities, respectively.

= 6-Mn and other metal components of 0.1096 or more, respectively, and the balance being 1.

MO is added to aluminum for the purpose of increasing the strength without adversely affecting the surface roughening treatment d3 of the support and printing process (', 0.30% wood vortex is insufficient in strength. On the other hand, if the amount is more than 3%, it is undesirable because the electrochemical surface roughening method cannot obtain a uniformly roughened surface.However, it is not preferable because it contains a compound called MC]2Al3, which causes stains during printing.

Fe has the effect of improving fatigue strength and providing fine surface roughness necessary for electrochemical surface roughening treatment and as a printing plate support.

However, if Fe exceeds 0.95%, it forms a coarse Al--Fe compound, which makes it easy to scratch the TJ (at the printing mouth), which is not preferable.

Ni precipitates finely and uniformly as a compound in Al, and further combines with Ec to form a stable compound, A I 9 f-eN i.

These properties of N1 have the effect of uniformizing the dispersion of "0" particles (Al-4"e compound), which serve as the nuclei for the formation of fine pits, when subjected to electrochemical surface roughening treatment, resulting in a uniformly roughened surface. The amount of Ni added is small (you can't expect such an effect if you add Ni,
If the amount is too large, the Al:+Ni compound becomes coarse, impairing the uniformity of the rough surface.

Li is added to refine the crystal grains of the agglomerates. 0.0
If it is less than 1%, it will have no effect, and if it exceeds 0.10%, it will result in a coarse At-Ti compound, which is undesirable. , T10.10% or less, 3
If it is 0.02% or less, the purpose of the present invention will not be impaired.

When 3i exceeds 0.20%, these components become Al-F
This is not preferred because it forms an e-3i compound and an AI-8r, Al-Fe compound, which tends to cause stains during printing.

In general, the purpose of the present invention will not be impaired as long as the impurities contained in the aluminum alloy of the present invention are as small as those contained in commercially available Al base metals, and 0.
Up to 20% CLI, Mn, and up to 0.10% of other metal components may be included.

The support of the present invention is produced by casting an aluminum alloy (having the above-mentioned composition), subjecting it to homogenization heat treatment, hot rolling, cold rolling, and intermediate annealing, and then subjecting it to a plate thickness reduction rate of 30% or more. Manufactured by applying cold rolling.

In order to improve the strength of the support of the present invention, it is effective to accumulate residual stress in the support.

Therefore, after intermediate annealing, the plate is subjected to finishing cold rolling to a thickness of 30% or more to provide a yield strength of 18 ko/mm' or more. If the cold rolling rate is less than 30%, the strength will be insufficient. Moreover, if it exceeds 90%, the rigidity becomes excessive and the performance as a printing plate deteriorates, which is not preferable. The monthly yield strength varies greatly depending on the amount of finish cold rolling as well as the chemical composition.
1-9 Cold rolling is added.

In addition, to increase the strength of the support, increase the amount of MO,
It is better to increase the amount of cold rolling, or to unnecessarily increase the amount of work hardening to increase the rigidity of the support. and the support will no longer adhere to each other, which can be harmful.

In such cases, the work-hardened support should be heated to 300°C.
It is best to partially anneal the material in step 2 to adjust its rigidity. In this case, annealing at a high temperature exceeding 300° C. is not preferable because the rigidity decreases too much. Also, due to the characteristics of annealing,
When the temperature is lower than 30'C, annealing becomes insufficient,
Rigidity is still greater.

Next, a method for surface treatment of an aluminum alloy support for a lithographic printing plate according to the present invention (two methods will be explained in detail).

The graining method applied to the aluminum alloy support of the present invention includes electrochemical sanding in a hydrochloric acid or nitric acid electrolyte.
``Electrochemical sand for raising 1] What about the raising method, the wire brush grain method in which the aluminum surface is scratched with metal wire A7, the ball grain method in which the aluminum surface is grained with an abrasive and the polishing method, and the nylon brush? Mechanical graining methods such as the brush graining method, in which the surface is grained with an iJl abrasive, can be used, and the over-cover graining methods described above can be used alone or in combination with tIC.

Electrochemical sand 11 standing method provides uniform roughness and appropriate 4x surface roughness 1! This has the advantage that it is less likely to cause blurring in non-image areas during printing.

The sand-Hitachi-C treated aluminum is then chemically crushed by acid or norkali. When an acid is used as an etching agent, it takes too long to destroy the microstructure, so an alkali is usually used as an etching agent. Is it good to use it as 111?

Examples of alkaline agents suitably used in the present invention include caustic soda, soda carbonate, aluminate sodium chloride, sodium metaethylate, W4M soda, potassium hydroxide, lidium hydroxide, and the like, with preferred concentrations and temperatures. The range is 1 to 50% and 20 to ioo'c-C, respectively, and the strip 41 is preferably such that the amount of aluminum dissolved is 5 to 20 g/m2.

After etching, pickling is performed to remove any dirt remaining on the surface. Examples of acids that can be used include nitric acid, sulfuric acid, phosphoric acid, chromic acid, butic acid, and hydrofluoric acid. In particular, for smut removal treatment after electrochemical surface roughening treatment, 15 to 65% by weight at a temperature of 50 to 90°C as described in JP-A-33-12739 @.
Method of contacting with sulfuric acid and Japanese Patent Publication No. 18-28123
Preferred is the alkali etching method as described in No.

The aluminum plate treated as described above can be used as a support for a lithographic printing plate, but it is preferable to further perform treatments such as anodization coating treatment and chemical conversion treatment as necessary.

The anodic oxidation treatment can be performed by a method conventionally used in this field. Specifically, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, etc., or a combination of two or more of these acids, are used. ) It is possible to form a positive oxidation film on the surface of the normimum support.

The conditions for anodizing treatment vary depending on the electrolyte used, so it cannot be generalized, but generally - the temperature of the electrolyte is 1 to 80%, the liquid temperature is 5 to 70°C, the current density is 0.5 ~
A range of 60 amperes/peak lI2, a voltage of 1 to 100 V, and an electrolysis time of 10 to 100 seconds is appropriate.

Among these anodic oxide coating treatments, British Patent No. 14
Preferred are the method of anodic oxidation in sulfuric acid at high current density as described in US Pat.

The anodized aluminum plate is further described in U.S. Patent No. 271
No. 4,066 and No. 3,181,461, by immersion in an aqueous solution of an alkali metal silicate, such as sodium silicate, or a water-soluble metal salt, as described in U.S. Pat. No. 3,860,426. Hydrophilic cellulose (e.g. carboxymethyl cellulose) containing (e.g. curved lead acetate) may also be provided.

On the aluminum alloy support for lithographic printing plates according to the present invention, a photosensitive layer conventionally known as a photosensitive layer of a PS plate can be provided to obtain a photosensitive lithographic printing plate, which is subjected to plate-making processing. The obtained lithographic printing plate has excellent performance.

The composition of the photosensitive layer includes the following.

■ Photosensitive layer consisting of diazo resin and binder Reaction of a diazonium salt disclosed in U.S. Pat. A condensation product of diphenylamine-p-diazonium salt and formaldehyde (so-called photosensitive diazo resin) is preferably used. This useful condensed diazo compound is listed in Japanese Patent Publication No. 49-18001, No. 4! IJ-
No. 45322, No. 49-/15323 M, etc.

These types of photosensitive diazo compounds are usually obtained in the form of water-soluble inorganic salts and can therefore be coated from an aqueous solution.

Or these water-soluble diazo compounds
Substantially water-insoluble photosensitizers are reacted with an aromatic or aliphatic compound having one or more phenolic hydroxyl groups, sulfonic acid groups, or both by the method disclosed in No. 7. Diazo resins can also be used. It can also be used as a reaction product with sea urchin hexafluorophosphate or (J detrafluorophosphate) as described in JP-A-56-121031@. Also preferred are diazo resins.

(2) Preferable O-quinonediazide compounds for photosensitive layers comprising O-quinonediazide compounds are O-footquinonediazide compounds, such as those disclosed in U.S. Pat. No. 2,766,118;
Same No. 2767092, Same No. 2772972, Same No. 2
No. 859112, No. 2907665 @, No. 304
No. 6110, No. 3046111, No. 304611
No. 5, No. 3046118, No. 3046119,
Same No. 3046120 @, Same No. 3046121, Same No. 3046122, Same No. 3046123 @, Same No. 30
No. 61430, No. 3102809, No. 31064
No. 65, No. 36357Q9, No. 3847443, and many other publications, and these can be suitably used.

■ Azide compound and binder (photosensitive layer consisting of a polymer compound) For example, British Patent No. 1235281, British Patent No. 149586
No. 1, JP-A-51-32331, JP-A No. 51-36128
In addition to the compositions comprising an azide compound and a water-soluble 1-1 or alkali-soluble polymer compound described in JP-A-50-5102@, JP-A-50-84302, and JP-A-50-8
Compositions comprising a polymer containing an azide group and a polymer compound as a binder as described in No. 4303 and No. 53-12984 are also included.

■Other photosensitive resin layers For example, polyester compounds disclosed in JP-A-52-96696@, British Patent No. 112277, Patent No. 1313309, Patent No. 1341004, Patent No. 137
Polyvinyl cinnamate resin described in No. 7747 etc.,
U.S. Patent No. 4072528, U.S. Patent No. 4072527 @
These include photopolymerizable photopolymer compositions described in, et al. The thickness of the photosensitive layer provided on the support is approximately 0,
1 to about 7 g, 'm', preferably 0.5 to /ICJ/
m2 range.

After image exposure of the PS plate, a resin image is formed by processing including development using conventional methods.

For example, the photosensitive layer consisting of a diazo resin and a binder
In the case of a PS plate having a lithographic printing plate, 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 PS plate having a photosensitive layer (1), after image exposure, the exposed portion is removed by developing with an alkaline aqueous solution to obtain a lithographic printing plate.

[Example] The present invention will be described in detail below based on examples.

Example 1 The alloy shown in Table 1 was cast by a normal method, and both sides were faceted to a thickness of 500 mm, width of 1000 mm, and length of 350 mm.
mm ingot, subjected to homogenization treatment if necessary, hot rolled, and successively cold rolled to 450'CX 3
After intermediate annealing by high-temperature, short-time heating for 0 seconds, finish cold rolling was performed with a plate thickness reduction rate of 90% to obtain an alloy plate with a thickness of 0.30 m1TI.

Table 1 These aluminum alloy plates were evaluated for printing suitability consisting of electrolytic etching properties, plate cracking properties, and stain resistance as indicated by stains in non-image areas. The results are shown in Table 2.

(1) Electrolytic etching properties The surface condition was observed with a scanning electron microscope, and the uniformity of pits was evaluated, and excellent results were indicated by ○, good results by △, and poor results by X.

(2) Printing suitability The printing plate processed by the following method is printed on the offset printing machine KOR.
After mounting the plate, 50,000 copies were printed and the degree of staining in the non-image area was evaluated.

The printed version was prepared as follows.

After graining an aluminum alloy plate with a rotating nylon brush in a suspension of pumice and water, the dissolution amount of aluminum was 8Q/1 using a 20% aqueous solution of caustic soda.
It was etched so that it became m2. After thoroughly washing with running water, pickling with a 25% nitric acid aqueous solution and washing with water. This substrate was subjected to alternating current electrolysis at a current density of 20 A/dm<2> or more in an electrolytic bath containing 15 to 2.5% nitric acid O as described in Japanese Patent Application Laid-Open No. 54-146234fj. Continued 15
After cleaning the surface by immersing it in a 50°C aqueous solution of 20% sulfuric acid for 3 minutes, an oxide film of 3 (II/dm2) was formed in an electrolytic solution containing 20% sulfuric acid at a bath temperature of 30°C. Established.

The following photosensitive layer was provided on the sample prepared in this way so that the dry coating amount was 25 o/m 2 .

Ester compound of naphthoquinone-1,2-diazido-5-sulfonyl chloride with acetin resin (Example 1 of U.S. Pat. No. 3,635,709)
) 0.75 g Talesol novolac resin 2.00 g Oil Blue #603 (manufactured by Orient Chemical Co., Ltd.) 0.04 q Edilene dichloride 1602-methyl-xyethyl acetate 12 (j Photosensitive lithographic plate thus obtained The printing plate was heated to 11!L using a 3kW metal halide lamp.
image exposure for 60 seconds from a distance of S i 02/Na2
It was developed with an aqueous sodium silicate solution having a molar ratio of 0 to 1.2 and a SiO2 content of 1.5%, washed with water, dried, and then gummed.

Table 2 No. of invention alloys A and B. Nos. 1 and 2 have high strength, so mechanical deformation of the printing plate is less likely to occur and printing durability is excellent. Further, since the pits formed by electrolytic etching are fine and uniform, the stain resistance is also good.

On the other hand, comparative example NO. Samples Nos. 3 and 4 have sufficiently high strength, but are poor in electrolytic etching properties and stain resistance. Also No.
5 is an Al050 material that has been used in the past and has a performance that can withstand practical use, but the plate cracking resistance is inferior here, so the overall evaluation is X and I.

Example 2 The alloy ingot shown in Table 3 was hot-rolled and cold-rolled to a predetermined thickness, intermediately annealed at 360°C for 1 hour, and then finished cold-rolled to a final thickness of 0.20 mm by varying the amount of final cold rolling. Prepare a thick board.

These alloy plates were evaluated for material strength, electrolytic etching properties, and printability using the same methods as in Example 1. The results are shown in Table 4.

Table 3 Table 4 If the yield strength is 18 kg/mm2 or more, it shows better side plate cracking resistance than conventional materials, and if it exceeds 20 kg/mm2, it shows very good side plate cracking resistance. Even if the amount of impurities is small, if the amount of alloying components added is too large, the electrolytic etching properties will deteriorate and the stain resistance will decrease.

Alloys ■ and K shown in Table 4 were cast, hot rolled, and cold rolled, then heated to 450°C at an average heating rate of 20°C/sec and held for 10 seconds, with an average cooling rate of 15'C. Intermediate annealing was performed by cooling to room temperature at 1/2 seconds and covering the material.

After that, an aluminum alloy plate with a thickness of 0.2011111 was prepared by applying 85% cold rolling to sufficiently work harden it and then annealing it at 300°C or less for 30 minutes. Table 5 shows the results of performance evaluation.

Table 5 Here, the rigidity was evaluated as follows.

The printing plate made by the method shown in Example 1 was cut into a red rail shape with a width of 30 mm and a length of 100 mm, and the test piece 1 was cut into a die 2 having a 90° concave portion as shown in FIG. U, the center part was press-bent by 90 degrees with a bending radius of 3 mm using punch 3, and as shown in FIG. 2, the opening angle α when released from the bending tool was measured and evaluated.

120'<α is × (excessive rigidity) 105° and α≦120° is △ (slightly excessive rigidity) α≦10
5° is ○ (rigidity is appropriate) A sharpener with a high content of alloy component MO that increases material strength and a large amount of finish cold rolling will increase the yield strength of the resulting alloy plate, or in such a case, the printing plate support The rigidity of the body becomes too large, making it difficult to attach it to the plate cylinder. Adding final heat treatment to adjust the rigidity of the printing plate support as in this example does not impair the performance of the printing plate, but rather improves handling properties, plate life (fatigue strength), etc. It has the effect of In addition, as in the comparative example (No. 21), the temperature was 300°C.
If heat treatment is performed at a temperature higher than I didn't like it as such.

[Effects of the Invention] The present invention has high strength as a printing plate, and can obtain a uniform rough surface and appropriate surface roughness through surface roughening treatment, particularly electrochemical roughening treatment, and when used as a printing plate. , an aluminum alloy support for lithographic printing plates is obtained which is less likely to cause stains in non-image areas and plate cracks.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the stiffness test, and FIG. 2 is an explanatory diagram of the test results of the test piece. 1...Test piece, 2...Die, 3...Punch. Patent applicant: Fuji Photo Film Co., Ltd. Sumitomo Light Metal Industries, Ltd.

Claims (6)

[Claims] (1) Mg0.30-3% (weight%: same below), Fe
0.15-0.50%, Ni 0.005-0.30%,
Contains 0.01-0.10% of Ti as an essential component, and 0.20% or less of Si, each as unavoidable impurities.
An aluminum alloy support for a lithographic printing plate containing Cu, Mn and 0.10% or less of each of other metal components, with the remainder being Al. (2) The aluminum alloy support for a lithographic printing plate according to claim (1), which has a yield strength of 18 kg/mm^2 or more. (3) The aluminum alloy support for a lithographic printing plate according to claim (1), which has a roughened surface and is anodized. (4) MgO0.30-3%, Fe0.15-0.50
%, Ni 0.005-0.30%, Ti 0.01-0.
Contains 10% as an essential component, 0.20% or less of each of Si, Cu, Mn, and other metal components of 0.10% or less each as unavoidable impurities, and the balance is Al.
Aluminum for lithographic printing plates, characterized in that an alloy consisting of the above is cast, subjected to homogenization heat treatment, hot rolling, cold rolling, intermediate annealing, and then final cold rolling with a plate thickness reduction rate of 30% or more. Method for manufacturing alloy support. (5) MgO0.30-3%, Fe0.15-0.50
%, Ni 0.005-0.30%, Ti 0.01-0.
An alloy containing 10% as an essential component, 0.20% or less each of Si, Cu, Mn and 0.10% or less each of other metal components as unavoidable impurities, and the balance Al is cast and homogeneous. Manufacture of an aluminum alloy support for lithographic printing, which is characterized by carrying out chemical heat treatment, hot rolling, cold rolling, and intermediate annealing, followed by final cold rolling with a plate thickness reduction rate of 30% or more, and further annealing. Method. (6) The method for producing an aluminum alloy support for a lithographic printing plate according to claim (5), wherein the annealing is performed at a temperature of 300° C. or lower.