JPH09234966A - Aluminum alloy plate for lithographic printing plate supporting body and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a cast plate of uniform and very fine casting formation by containing respectively the specified amount of one or two kinds of Fe, Si, Cu and the like and forming the remaining part of Al and unavoidable impurities in the alloy constitution of an aluminum alloy plate in the continuous casting rolling method. SOLUTION: The alloy constitution of an aluminum alloy plate used as a lithographic printing plate substrate contains one or two kinds of Fe of 0.8wt.% or less, Si of 1.0wt.% or less, Cu of 0.2wt.% or less, Be of 0.0002-0.01wt.% and Sn of 0.001-0.10wt.%, and the remaining part is formed of Al and unavoidable impurities. The hot solution of molten aluminum alloy is fed between movable casts, and cast plates of thickness of 30mm or less are cast continuously and cold rolled, and if required, annealed intermediately, and then cold rolled simultaneously to complete the manufacture of the aluminum alloy plates in the continuous casting rolling method. The aluminum alloy plates thus formed are improved in its uniformity of outer appearance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy plate for a lithographic printing plate support and a method for producing the same, more specifically, an Al alloy plate produced by a continuous casting and rolling method, which is cast by improving the alloy composition. The present invention relates to an aluminum alloy plate which can be used as a lithographic printing plate support with improved plate quality and a method for producing the same.

[0002]

2. Description of the Related Art Generally, as a method for producing an aluminum alloy sheet, a slab made by casting a molten aluminum alloy by a semi-continuous casting method is subjected to homogenizing heat treatment, and then hot rolling and cold rolling (annealing if necessary). Alternatively, the molten aluminum alloy is continuously supplied between the movable molds (the water-cooled drums 4 and 5 shown in FIG. 1 or the water-cooled belts 8 and 9 shown in FIG. 2) to obtain a cast plate having a plate thickness of 30 mm or less, which is then formed. The so-called continuous casting and rolling method (hereinafter referred to as continuous casting and rolling method) in which a sheet material having a desired size and performance is cold-rolled (may be annealed before, during, or afterward if necessary) is generally used. Is.

However, the aluminum alloy plate used for the lithographic printing plate support is formed into a plate by the above-mentioned process and then subjected to surface treatment such as chemical etching, electrochemical etching and anodic oxidation in the process of working as a lithographic printing plate. The homogeneity of the metallurgical structure of the material has a great influence on the surface quality. That is, if the metallographic structure varies, the appearance after the surface treatment becomes non-uniform in the form of strips or spots, which causes not only poor appearance but also printing defects due to non-uniformity of etching pits. Non-uniformity of the cast structure is one of the causes of the variation in the metal structure.

For example, the cast structure of the slab cast by the semi-continuous casting method generally changes its structure such as a chill layer, a coarse cell layer and a fine cell layer as it moves from the casting surface to the inside. Here, the combined portion of the chill layer and the coarse cell layer is generally called a frame and has an unstable metal structure, which adversely affects the surface quality. Therefore, it is generally scraped off by chamfering. The aluminum alloy sheet is manufactured by this method by subjecting the slab thus face-milled to homogenizing heat treatment and hot rolling, and then cold rolling (annealing if necessary) to obtain a predetermined sheet.

Further, the continuous casting and rolling method is a very effective method for improving the yield and the energy efficiency since the ingot homogenization heat treatment and the hot rolling step are omitted, and the cooling rate of the molten metal is increased. Since the alloy components are easily forced to form a solid solution and the second phase particles are likely to be fine, it is possible to generally obtain an aluminum alloy plate excellent in impact resistance, formability and fatigue strength. It is said that an aluminum alloy plate having a surface treatment such as a support aluminum alloy plate has an advantage that an aluminum plate having excellent gloss and corrosion resistance can be obtained (for example, JP-A-58-224136).

However, in this continuous casting and rolling method, since the mold moves continuously with respect to the molten metal supplied according to the basic principle of its manufacturing, the contact between the molten metal and the movable mold during casting is unstable. For this reason, there is a problem that the solidification rate of the molten metal is likely to vary, which causes a non-uniform casting structure of the cast plate. The aluminum alloy rolled plate produced by such a cast plate having a non-uniform cast structure has a non-uniform surface treatment, resulting in poor appearance. As with the semi-continuous casting method, it is difficult to reduce the unevenness of the cast structure of the cast plate produced by the continuous casting and rolling method by chamfering, because the sheet thickness is about 30 mm or less and it is thin. In addition, since this microstructure variation usually affects the depth of several mm even in the plate thickness or even the center part of the plate thickness, it is not a realistic method considering the yield.

As described above, the continuous casting and rolling method is more attractive than the semi-continuous casting method in terms of production efficiency and characteristics, but unevenness occurs in the casting structure and it is difficult to remove this portion. Therefore, it is said that it is not appropriate to apply this to the production of an aluminum alloy plate which is subjected to a surface treatment like an aluminum alloy plate for a lithographic printing plate support and is required to have a uniform appearance after treatment. Was the general view so far.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the above conventional techniques. Specifically, in the production by the continuous casting and rolling method, by obtaining a cast plate having a uniform fine casting structure, it is possible to obtain a highly uniform appearance by surface treatment such as chemical etching, electrochemical etching and anodic oxidation. An object is to find an aluminum alloy plate for a lithographic printing plate support which can obtain a surface and a method for producing the same.

[0009]

The invention according to claim 1 for solving the above-mentioned problems is an aluminum alloy plate produced by a continuous casting and rolling method, wherein the alloy composition is Fe 0.8 wt%.
Below, Si 1.0 wt% or less, Cu 0.2 wt% or less,
Further, Be 0.0002 to 0.01 wt% and Sn0.
001 to 0.10 wt% of 1 type or 2 types,
An aluminum alloy plate for a lithographic printing plate support, wherein the balance comprises Al and unavoidable impurities,

A second aspect of the present invention is a method for producing an aluminum alloy sheet by the continuous casting and rolling method, wherein Fe0.
8 wt% or less, Si 1.0 wt% or less, Cu 0.2 wt
% Or less, and further contains one or two of Be 0.0002 to 0.01 wt% and Sn 0.001 to 0.10 wt%, and the balance is supplied between the movable molds by the molten aluminum alloy from Al and unavoidable impurities. A method for producing an aluminum alloy plate for a lithographic printing plate support, which comprises continuously casting a cast plate having a thickness of 30 mm or less, cold rolling, intermediate annealing if necessary, and final cold rolling. Is.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The invention of claim 1 is an aluminum alloy plate for a lithographic printing plate support, which is produced by a continuous casting and rolling method and has a predetermined alloy composition. The composition of the aluminum alloy in the present invention will be described below. Fe is 0.8 wt%
The range is as follows. It is preferably 0.5 wt% or less, more preferably 0.4 wt% or less. Fe has the function of making the electrolytically roughened surface uniform. Fe is an element that forms an Al-Fe-based and Al-Fe-Si-based intermetallic compound in combination with other elements in the aluminum alloy. Among these intermetallic compounds, the intermetallic compound of 1 to 20 μm is It has the effect of refining the crystal grains and the effect of forming a uniform and fine electrolytic rough surface. However, the reason for setting Fe in the above range is that when the content exceeds 0.8 wt%, it is 20 μm.
This is because the formation of a coarse compound exceeding m makes the electrolytic roughened surface non-uniform.

Next, Si is set to 1.0 wt% or less. Preferably 0.5 wt% or less, more preferably 0.2 wt
% Or less. Si is usually included as an impurity, and is 1.0
If the content exceeds wt%, defects such as microscopically insufficient spots of insufficient etching, so-called unetched portions, tend to appear in the electrolytic surface roughening treatment, which is not preferable. Therefore, Si is in the above range.

Cu is 0.2 wt% or less. The reason why Cu is limited to 0.2 wt% or less is that when Cu exceeds 0.2 wt% as an impurity, the recesses (pits) generated by the electrochemical graining treatment are likely to become coarse, and the non-image as a printing plate is not formed. This is because the corrosion resistance of the part decreases. Preferably 0.15% wt or less, more preferably 0.1 wt
% Or less is good.

Be is set to 0.0002 to 0.01 wt%. Be is an element that is not contained in ordinary aluminum ingots, but as a result of repeated studies by the present inventors, it has an effect of suppressing surface oxidation in an aluminum alloy melt, and Be cannot be added to a casting nozzle during continuous casting. It has the effect of preventing the adhesion of oxides, eliminating the disturbance in the width direction of the molten metal, and stabilizing the contact between the molten metal and the mold during casting. If Be is less than 0.0002 wt%, the above effect cannot be obtained, and if it exceeds 0.01 wt%, the effect is saturated and wasted.

Sn is set to 0.001 to 0.10 wt%. Although Sn is an element that is not contained in ordinary aluminum ingots, the inventors of the present invention have conducted extensive research, and as a result, in addition to the same effect as Be, in addition to the effect of adhesion between the molten aluminum alloy and the mold during continuous casting. There is a lubricating action to prevent. Generally, in continuous casting, when the molten aluminum alloy comes into contact with the mold and is solidified, sticking may occur between the molten metal and the continuously moving mold. This fixed portion changes the cooling rate and destroys the aluminum coating layer on the surface of the mold, which causes discontinuity in the cast structure near the surface and causes striped pattern defects on the coil surface. The addition of Sn has the effect of preventing this sticking phenomenon and stabilizing the contact between the molten metal and the mold during casting. Sn0.
If it is less than 001 wt%, there is no effect, and if it exceeds 0.10 wt%, the effect is saturated and useless. In addition, Be and S
The above effect can be obtained with any one type of n, but it is more preferable to add both types.

Other unavoidable impurities include Mn and Cr contained in ordinary aluminum ingots, but there is no particular problem if they are about 0.05 wt% or less. Further, as an optional additional element, the inclusion of each of Ti and B in an amount of 0.1 wt% or less is effective for refining the solidification structure during casting. The aluminum alloy plate for a lithographic printing plate support having the above-described structure can have a uniform appearance by various surface treatments.

Next, the invention of claim 2 relates to a specific manufacturing method for manufacturing the aluminum alloy plate for a lithographic printing plate support by a continuous casting and rolling method. That is, the molten aluminum alloy having the above composition is supplied between the movable molds to continuously cast a cast plate having a thickness of 30 mm or less, which is cold-rolled, optionally annealed, and finally cold-rolled. It is a feature. Here, the reason for continuously casting into a cast plate having a plate thickness of 30 mm or less is that, as described above, in the continuous casting and rolling method, the cooling rate of the molten metal can be increased, so that the alloy components are easily forced to form a solid solution, Moreover, since the second phase particles are likely to be fine, various advantages can be obtained as material properties, but the plate thickness is 30 mm.
If it exceeds, the cooling rate sufficient for forced solid solution cannot be obtained and the intermetallic compound becomes coarse, which is not preferable. Further, if the plate thickness is too large, the number of times of rolling in the lower step increases, which is not economical. Therefore, the thinner the thickness, the better, but preferably 15 mm or less, more preferably 10 mm or less.

Examples of continuous casting in the continuous casting and rolling method of interest include the Hunter method using a twin drum shown in FIG. 1 and the 3C method, and the Hesley method using a twin belt shown in FIG. However, the present invention is not limited to these specific methods. 1 and 2 show an example of continuous casting according to the present invention,
It is explanatory drawing which shows a mode that the continuous casting board 6 is manufactured with the movable mold device by the twin drums 4, 5 and the twin belts 8, 9. FIG.

First, an aluminum alloy melt 3 adjusted to a desired alloy composition is temporarily stored in a molten metal pool (usually called a head box) 1 from a melting and holding furnace (not shown), and then a casting nozzle 2 It is guided to a water-cooled movable mold (drums 4, 5, belts 8, 9). In addition, 6 is a cast plate.

The cast plate 6 cast as described above may be rolled immediately after that, or wound as it is on a coil, if necessary. After that, it is rolled to a desired size by cold rolling, but if necessary, before, in the middle,
After that, it is annealed once to several times to obtain a predetermined plate or strip. Further, performing alkali cleaning during the cold rolling is effective in removing oxide films and other surface foreign matters formed on the surface of the cast plate during continuous casting and rolling,
A more uniform rough surface can be obtained.

When the aluminum alloy plate for a lithographic printing plate support is used as a lithographic printing plate support, it is subjected to various surface treatments such as chemical etching, electrolytic etching and anodic oxidation treatment. Be uniform,
It is necessary to obtain a uniform rough surface. The aluminum alloy plate for a lithographic printing plate support produced by the method of the present invention as described above, as is clear in Examples described later,
The final surface treatment provides a uniform appearance surface.

Next, the aluminum alloy plate for a lithographic printing plate support of the present invention is used as a lithographic printing plate support (PS plate, Pre-s).
Optimized Printing Plate)
Various surface treatment methods in the case of actually using the above will be described in detail. The plate surface is sharpened electrochemically in hydrochloric acid or nitric acid electrolyte, electrochemically sharpened with aluminum, the aluminum surface is scratched with a metal wire using the wire brush grain method, and the aluminum surface is sanded with abrasive balls and an abrasive. A mechanical graining method such as a ball graining method for graining or a brush graining method for graining the surface with a nylon brush and an abrasive can be used, and any of the above graining methods can be used alone or in combination. The aluminum alloy plate treated in this way is chemically etched with acid or alkali. When an acid is used as an etching agent, it takes time to destroy the fine structure, which is industrially disadvantageous, but it can be improved by using an alkali as the etching agent.

Suitable alkali agents are caustic soda, sodium carbonate, sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide, lithium hydroxide and the like, and the preferable ranges of concentration and temperature are 1 to 50, respectively.
wt% is 20 to 100 ° C., and the amount of Al dissolved is 5 to 2
It is preferable that the condition be 0 g / m ² . After the etching, acid cleaning is performed to remove stains (smut) remaining on the surface. The acids used are nitric acid, sulfuric acid, phosphoric acid,
Chromic acid, hydrofluoric acid, and hydrofluoric acid are used. Particularly, for the smut removing treatment after the electrochemical graining treatment, a method of contacting with sulfuric acid of 15 to 65 wt% at a temperature of 50 to 90 ° C. as described in JP-A-53-12739 and JP The alkali etching method described in JP-A-48-28123 is preferable.

The aluminum alloy plate treated as described above can be used as a support for a lithographic printing plate. However, if necessary, it is desirable to further perform anodizing treatment, caustic treatment or the like. The anodizing treatment can be performed by a method conventionally performed in this field. Specifically, when a direct current or an alternating current is applied to aluminum in sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, etc., or an aqueous solution or a non-aqueous solution containing a combination of two or more thereof, the surface of the aluminum support It is possible to form an anodized film on. The conditions of anodic oxidation cannot be unconditionally determined because they vary depending on the electrolytic solution used, but generally the electrolytic solution concentration is 1 to 8
0 wt%, liquid temperature 5 to 70 ° C., current density 0.5 to 60 amperes / dm ² , voltage 1 to 100 V, electrolysis time 10 to 10
A range of 0 seconds is appropriate.

Among these anodized film treatments,
A method of anodizing at high current densities in nitric acid used in the invention described in British Patent No. 1,412,768 and described in US Pat. No. 3,511,661. The method of anodic oxidation using phosphoric acid as an electrolytic bath is preferable. Anodized aluminum plates are further described in US Pat. Nos. 2,714,066 and 3,18.
Treatment with an alkali metal silicate such as those described in US Pat. No. 1,461, for example, by dipping in an aqueous solution of sodium silicate, or in US Pat. No. 3,860,
An undercoat layer of hydrophilic cellulose (eg, carboxymethylcellulose) containing a water-soluble metal salt (eg, zinc acetate) can also be provided, as described in US Pat.

A photosensitive layer conventionally known as a 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 (PS plate). The lithographic printing plate thus obtained has excellent performance. The composition of the photosensitive layer includes the following. 1. Photosensitive layer comprising diazo resin system and binder US Pat. Nos. 2,063,631 and 1,667,
No. 415, which is a reaction product of a diazonium salt and an organic condensing agent having a reactive carbonyl group such as aldol and acetal, which is a condensation product of diphenylamine-p-diazonium salt and formaldehyde (so-called A photosensitive diazo resin) is preferably used. Other useful condensed diazo compounds are JP-B-48-4.
No. 8001 and No. 49-45322 are disclosed. These types of photosensitive diazo compounds are usually obtained in the form of water-soluble inorganic salts and can therefore be applied in aqueous solution. Further, these water-soluble diazo compounds are reacted with an aromatic or fatty acid group compound having one or more phenolic hydroxyl groups, sulfonic acid groups or both by the method disclosed in JP-B-47-1167, It is also possible to use a substantially water-soluble photosensitive diazo resin which is a reaction product. Also, JP-A-56-12
A diazo resin as described in Japanese Patent No. 1031 is also preferable.

2. Photosensitive Layer Consisting of o-Quinonediazide Compound A particularly preferred o-quinonediazide compound is an o-naphthoquinonediazide compound, for example, US Pat.
No. 66,118, No. 2,767,092, No. 2,
772,972, 2,859,112, 2,907,665, 3,046,110, 3,046,111, 3,046,115,
No. 3,046,118, No. 3,046,119
No. 3,046,120 No. 3,046,12
No. 0, No. 3,046,121, No. 3,046,1
No. 22, No. 3,046,123, No. 3,061,
No. 430, No. 3,102,809, No. 3,10
No. 6,465, No. 3,635,709, No. 3,6
It is described in many publications including No. 47,443, and any of them can be preferably used.

3. Photosensitive layer comprising azide compound and binder (polymer compound) For example, British Patent Nos. 1,235,281 and 1,4
95,861, JP-A-51-32331 and JP-A-51
No. 36128, and a composition comprising an azide compound and a water-soluble or alkali-soluble polymer compound, as well as JP-A-50-5102 and 50-84302.
No. 50-84303, No. 53-12984, and a composition comprising a polymer containing an azide group and a polymer compound as a binder.

4. Other photosensitive resin layers For example, polyester compounds disclosed in JP-A-52-96696, British Patents 112,277, 1,313,309, 1,431,004, and Polyvinyl cinnamate resins described in No. 1,377,747 and the like, and photopolymerizable photopolymers described in US Pat. Nos. 4,072,528 and 4,072,527. A composition is included.

The amount of the photosensitive layer formed on the support is about 0.1 to 7 g / m ² , preferably 0.5 to 4 g / m ² .
It is in the range of m ² . After the PS plate is imagewise exposed, a resin image is formed by a process including a conventional development. For example, the photosensitive layer 1. comprising a diazo resin and a binder. In the case of the PS plate having the composition (1), the photosensitive layer in the unexposed portion is removed by development after image exposure to obtain a lithographic printing plate. Further, the photosensitive layer 2. In the case of the PS plate having the composition (1), the exposed portion is removed by developing with an aqueous alkali solution after image exposure to obtain a lithographic printing plate.

[0031]

【Example】

(Example 1) A molten aluminum alloy having the composition shown in Table 1 was used as an example of the present invention and as a comparative example by a hunter method using twin drums 4 and 5 shown in FIG.
mm cast plate 6 coil. Casting conditions other than the above are as follows. -Release agent: Solution of fine carbon powder dissolved in water-Plate width of casting plate: 1300 mm-Melting temperature: 700 ° C-Casting speed: 1000 mm / min. -Cooling rate: 300 to 700 ° C / sec. These cast plate coils are cold-rolled by a conventional method, and the results are shown in Table 1.
Intermediate annealing was carried out under the conditions shown in, and further cold rolling was carried out to manufacture an aluminum alloy plate having a thickness of 0.3 mm.

[0032]

[Table 1]

Next, these rolled aluminum alloy plates were grained with a rotating nylon brush in a suspension of pumice and water, and then a 20 wt% aqueous solution of caustic soda was used to dissolve aluminum to 5 g / m ^2. It was chemically etched. After washing this thoroughly with running water, 25w
A substrate was prepared by pickling with a t% nitric acid aqueous solution and then washing with water.
The substrate prepared in this way is disclosed in Japanese Patent Application Laid-Open No. 54-14623.
As described in Japanese Patent Laid-Open No. 4 (1994), electrolytic etching was performed in an electrolytic solution containing 1.5 wt% of nitric acid with an alternating current having a current density of 20 A / dm ² . Then, add 3% to 15 ° C sulfuric acid at 50 ° C.
After rinsing for a minute to wash the surface, an anodic oxide coating of 3 g / m ² was formed at a bath temperature of 30 ° C. in an electrolytic solution containing 20 wt% of sulfuric acid as a main component. With respect to the aluminum alloy plate prepared as described above, the uniformity of the appearance and the uniformity of the rough surface after the above surface treatments were evaluated in the following manner. The uniformity of the cast structure of the cast plate was evaluated in the following manner.

The evaluation method is as follows. (1) Uniformity of casting structure The surface and cross section of the casting plate were mirror-polished and then etched, and the uniformity of the casting structure was observed with a microscope. Excellent uniformity ⊚, good one ○, slightly inferior It was judged that there was a poor one and a poor one. (2) Uniformity of appearance after chemical etching After etching with caustic soda, the appearance is visually observed, and the appearance is excellent ◎, good ○,
The evaluation was made as “Slightly inferior” and “Inferior” as ×. (3) Uniformity of electrolytically etched rough surface The surface condition was observed with a scanning electron microscope to evaluate the uniformity of the pits. went. (4) Uniformity of appearance after anodizing treatment Excellent in uniformity of appearance after anodizing treatment ◎, good ○, slightly poor Δ, poor ×
The judgment was made as follows. The test results are shown in Table 2.

[0035]

[Table 2]

As is clear from Table 2, the aluminum alloy plate produced under the conditions of the present invention has no structural defects and is excellent in uniformity of appearance, and is used as an aluminum alloy plate for a lithographic printing plate support. It was confirmed that it was possible.

(Example 2) In order to perform a printing durability test, the sample No. 1 in Example 1 and Table 1 was used. The aluminum alloy plate of No. 3 was chemically etched, electrolytically etched, and anodized under the same conditions as in Example 1, and then a photosensitive layer having the following composition was applied at a coating amount of 2.5 g / m ² when dried. It was provided so that Ester compound of naphthoquinone-1,2-diazido-5-sulfonyl chloride with hirogalol and acetone resin (described in US Pat. No. 3,635,709) 0.75 g cresol novolac resin 2.00 g oil blue # 630 (Orient Chemical) 0.04 g Ethylene dichloride 16 g 2-Methoxyethyl acetate 12 g

The photosensitive lithographic printing plate thus obtained was brought into close contact with a transparent positive image and PS light (having a light source of Toshiba Metal High Ride Lamp MU2000-2-0L type 3KW from a distance of 1 m, from Fuji Photo Film Co., Ltd.) A sample (commercially available) was exposed for 30 seconds, immersed in a 5% aqueous solution of sodium silicate for 1 minute for development, washed with water and dried to prepare a sample. When a 100,000-sheet printing test was conducted on this sample, it was confirmed that there was no problem in printing durability.

[0039]

As is apparent from the above description, according to the present invention, the aluminum alloy plate for a lithographic printing plate support produced by the continuous casting and rolling method has an appearance even in various surface treatments required for this application. Of the continuous casting and rolling method can fully utilize the advantages of the continuous casting and rolling method.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of manufacturing a continuously cast plate by a movable mold device (Hunter method) using twin drums.

FIG. 2 is an explanatory view showing an example of manufacturing a continuously cast plate by a movable mold device (Hesley method) using a twin belt.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hot water pool (head box) 2 Casting nozzle 3 Molten metal 4, 5 Drum (movable mold) 6 Casting plate 8, 9 Belt (movable mold) 10-13 Roller

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication C22F 1/04 C22F 1/04 A (72) Inventor Hidemitsu Matsumoto 2-6 Marunouchi, Chiyoda-ku, Tokyo No. 1 in Furukawa Electric Co., Ltd. (72) Inventor Hirokazu Sakaki 4000 Kawasakiri, Yoshida-cho, Harahara group, Shizuoka Prefecture Fuji Shashin Film Co., Ltd. Fuji Shashin Film Co., Ltd.

Claims (2)

[Claims] 1. An aluminum alloy plate produced by a continuous casting and rolling method, the alloy composition of which is 0.8 wt% or less of Fe,
Si 1.0 wt% or less, Cu 0.2 wt% or less, Be 0.0002 to 0.01 wt% and Sn 0.001
An aluminum alloy plate for a lithographic printing plate support, containing 0.1 to 0.10 wt% of one or two kinds, and the balance consisting of Al and unavoidable impurities. 2. A method for producing an aluminum alloy sheet by a continuous casting and rolling method, wherein Fe 0.8 wt% or less, Si 1.
0 wt% or less, Cu 0.2 wt% or less, and Be0.
0002-0.01 wt% and Sn 0.001-0.1
An aluminum alloy melt containing 0 wt% of one or two kinds and the balance of Al and unavoidable impurities is supplied between the movable molds, continuously cast into a casting plate having a thickness of 30 mm or less, and cold-rolled. And a method for producing an aluminum alloy plate for a lithographic printing plate support, which comprises performing intermediate annealing if necessary and further performing final cold rolling.