JP2003019877A - Method for manufacturing support for lithographic printing plate, support for lithographic printing plate, and lithographic printing original plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a support, for a lithographic printing plate, which is free from the generation of a chatter mark, even when the surface of a reclaimed aluminum plate is rapidly roughened. SOLUTION: This method for manufacturing a support for a lithographic printing plate comprises a surface roughening step to roughen at least one side of the reclaimed aluminum plate manufactured using a reclaimed aluminum base metal. This surface roughening step includes a DC electrolytic surface roughening step to perform an electrolytic surface roughening process using direct current, in an acidic electrolytic solution, which makes the reclaimed aluminum plate pass through the acidic electrolytic solution so that the plate is way off from a positive pole and a negative pole by a distance which gives rise to the electrolytic surface roughening process by an anode and a cathode immersed in the acidic electrolytic solution, in an alternately arranged fashion, while the direct current is applied to the anode and the cathode. Thus the manufacturing method is characterized in that the surface of the reclaimed aluminum plate is roughened by the electrolytic process through the described steps. Also the support for the lithographic printing plate manufactured by the manufacturing method and the lithographic printing plate are provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a support for a lithographic printing plate, a support for a lithographic printing plate, and a lithographic printing plate precursor, and particularly to a lithographic printing plate having excellent printing performance without uneven processing. The present invention relates to a method for producing a lithographic printing plate support capable of producing a support, a lithographic printing plate support, and a lithographic printing original plate having the lithographic printing plate support as a support.

[0002]

2. Description of the Related Art A lithographic printing original plate, which is an original plate of a lithographic printing plate, generally has a roughened surface of an aluminum plate obtained by rolling pure aluminum or an aluminum alloy (hereinafter sometimes referred to as "aluminum or the like"). And then anodizing the written surface,
A lithographic printing plate support is formed by forming an anodic oxide film, and a photosensitive resin or a heat-sensitive resin is applied to the surface of the lithographic printing plate support on which the anodic oxide film is formed so that it is photosensitive or heat-sensitive. It is produced according to the procedure of forming a plate-making layer. These photosensitive resin layers and heat-sensitive resin layers including an undercoat layer and a protective film layer are disclosed in JP-A-2000-62.
It is known in Japanese Patent Application Laid-Open No. 333, Japanese Patent Application Laid-Open No. 59-101651 and Japanese Patent Application Laid-Open No. 60-149491.

A lithographic printing plate is produced by printing a printed image such as characters and pictures on the plate making layer of the lithographic printing original plate and developing it.

In the roughening treatment, mechanical roughening treatment is performed by a brush roller having bristles such as nylon or a polishing roller having a polishing cloth on the surface, and the surface of the recycled aluminum plate is chemically treated in an alkaline solution. Etching treatment to roughen the surface, and the recycled aluminum plate as one of the electrodes, an alternating current is applied in an acidic electrolytic solution, an electrolytic surface roughening treatment for roughening the recycled aluminum plate by performing AC electrolysis. Has been done. In the roughening,
In order to improve the water retention of the non-image area during printing and the ease of printing (the visibility of the plate surface), mechanical roughening treatment is generally performed, followed by etching treatment and electrolytic roughening treatment. Target. Furthermore, after the electrolytic surface-roughening treatment and the chemical surface-roughening treatment, a desmut treatment of immersing the regenerated aluminum plate in an acidic solution is performed, and the regeneration is performed by the electrolytic surface-roughening and the chemical surface-roughening treatment. The oxides, hydroxides and intermetallic compounds of the elements contained in the aluminum plate may be removed.

[0005]

However, since new ingots such as newly refined pure aluminum and aluminum alloys produced by adding a specific amount of alloying elements to the above pure aluminum are expensive, A lithographic printing plate support obtained by roughening an aluminum plate produced by rolling is also expensive, and therefore a lithographic printing plate precursor having a lithographic layer formed on the roughened surface of the lithographic printing plate support is also expensive. .

On the other hand, recycled aluminum ingots such as scrap materials and recycled materials are cheaper than the new ingots and consume less energy during manufacturing.
If a lithographic printing plate precursor can be manufactured from a recycled aluminum plate manufactured from the recycled aluminum ingot instead of the plate made of aluminum or the like, not only is cost and energy saved, but also resource saving is achieved.

However, unlike the new ingot, the recycled aluminum ingot has almost no control of alloy components,
Contains various impurities.

Therefore, various intermetallic compounds and precipitates derived from the impurities are exposed on the surface of the recycled aluminum plate. The intermetallic compounds and deposits are often not completely removed by the conventional surface roughening treatment, and the intermetallic compounds and deposits remaining on the surface of the recycled aluminum plate are not printed on the non-image area of the printing paper surface. It was often the cause of severe ink stains.

Further, since the surface of the recycled aluminum plate is difficult to be uniformly roughened by the conventional electrolytic roughening treatment, and the surface has a non-uniform surface shape, it becomes a blanket or blanket of the offset roller. There is also a problem that ink adheres, and so-called blanc stain is likely to occur, in which the ink adheres to the printing paper surface.

The conditions of the etching treatment, the desmutting treatment, the electrolytic surface roughening treatment, and the like have been studied in detail, and the recycled aluminum plate does not cause severe ink stains or stains and has excellent printing durability. Various manufacturing methods capable of stably manufacturing the lithographic printing plate have been proposed.

With the above-mentioned manufacturing method, it becomes possible to manufacture a good quality lithographic printing original plate from the recycled aluminum plate at a relatively low speed.

However, when the treatment is carried out at a high speed in order to improve the productivity, the surface of the lithographic printing plate support, which is obtained by roughening the recycled aluminum plate, is spread along the width direction of the lithographic printing plate support. In some cases, uneven processing called striped chatter marks occurred.

According to the present invention, when a support for a lithographic printing plate is manufactured from a recycled aluminum plate, the chatter mark does not occur even if a roughening treatment is carried out at a high speed, and a support for a lithographic printing plate is manufactured. An object of the present invention is to provide a method, a lithographic printing plate support produced by the above production method, and a lithographic printing original plate having a plate making layer laminated on the roughened surface of the lithographic printing plate support.

[0014]

The invention according to claim 1 comprises a roughening step of roughening at least one surface of a recycled aluminum plate manufactured from recycled aluminum metal, The roughening step comprises a direct current electrolytic roughening step of electrolytically roughening the recycled aluminum plate in an acidic electrolytic solution by direct current in the acidic electrolytic solution, and in the direct current electrolytic roughening step, alternating with each other. While applying a direct current to the anode and the cathode that are immersed in the acidic electrolytic solution, the recycled aluminum plate, the distance by which the electrolytic roughening occurs by the anode and the cathode The present invention relates to a method for producing a lithographic printing plate support, which comprises passing through the acidic electrolytic solution so as to be separated from the anode and the cathode and performing electrolytic surface roughening treatment.

In the method for producing a lithographic printing plate support, the recycled aluminum plate undergoes a cathodic reaction when passing near the anode and an anodic reaction when passing near the cathode.

Since the anodes and the cathodes are alternately arranged as described above, the cathode reaction and the anode reaction occur alternately at any part of the surface of the regenerated aluminum plate.

Therefore, the generation of chatter marks on the surface of the recycled aluminum plate can be effectively prevented.

According to the method for producing the lithographic printing plate support, the average surface roughness Ra (JI
S B0601-1994) is 0.3 to 0.6 μm, L ^* value shown in CIELAB space is 50 to 95, and ΔE ^* _ab is less than 2 and an excellent lithographic printing plate support is obtained.

According to a second aspect of the present invention, in the DC electrolytic surface roughening step, the direct current electrolytic surface roughening steps are alternately arranged along a transfer surface which is a transfer path of the recycled aluminum plate. DC electrolysis rough comprising an anode and a cathode immersed in an acidic electrolyte, and at least one of the anode and the cathode and one or more electrolytic cells containing the acidic electrolyte. The present invention relates to a method for producing a support for a lithographic printing plate, which comprises performing an electrolytic surface-roughening treatment using a surface-rendering device.

When the regenerated aluminum plate is conveyed inside the DC electrolytic surface roughening device, the regenerated aluminum plate passes near the anode and the cathode, and a cathode reaction and an anode reaction occur alternately on the surface. Therefore, it is possible to effectively prevent the generation of chatter marks on the surface of the recycled aluminum plate.

According to a third aspect of the present invention, in the roughening step, prior to the direct current electrolytic roughening step, the recycled aluminum plate is electrolytically roughened in a hydrochloric acid aqueous solution containing hydrochloric acid as a main acid component. A method for producing a support for a lithographic printing plate, which comprises a preliminary electrolytic surface-roughening step of surface-treating.

In the method for producing the lithographic printing plate support, the regenerated aluminum plate is subjected to a preliminary electrolytic surface roughening treatment in an aqueous hydrochloric acid solution prior to the DC electrolytic surface roughening step. It is possible to particularly effectively prevent the occurrence of streak-like process unevenness on the surface of the printing plate support.

The invention according to claim 4 is characterized in that in the roughening step, prior to the (a) direct current electrolytic surface roughening step, the recycled aluminum ingot is subjected to an etching treatment by bringing it into contact with an alkaline solution. For a lithographic printing plate comprising an etching step, and (b) a post-etching step in which the regenerated aluminum plate electrolytically surface-roughened in the DC electrolytic surface-roughening step is etched by bringing it into contact with an alkaline solution. The present invention relates to a method for manufacturing a support.

In the method for producing the lithographic printing plate support, the pre-etching step effectively removes oil and the like adhering to the surface of the regenerated aluminum plate. The electrolytic surface roughening treatment proceeds more uniformly, and a highly roughened surface is obtained.

Further, the aluminum hydroxide film formed on the surface of the regenerated aluminum plate in the DC electrolytic surface roughening step is effectively removed by etching with an alkaline solution in the latter etching step.

Therefore, if the recycled aluminum plate that has been roughened in the roughening step is anodized, an anodized film having high uniformity and very few defects is formed on the surface.

The invention according to claim 5 has a middle-stage etching step of etching the regenerated aluminum plate electrolytically surface-roughened in the preliminary electrolytic surface-roughening step by bringing it into contact with an alkaline solution. In the direct current electrolytic surface roughening step, the present invention relates to a method for producing a lithographic printing plate support, in which the recycled aluminum plate etched in the middle etching step is electrolytically surface roughened.

In the preliminary electrolytic surface-roughening step, a film of aluminum hydroxide may be formed on the surface of the recycled aluminum plate. In the method for producing the lithographic printing plate support, the preliminary electrolytic treatment is carried out. Since the aluminum hydroxide film is removed by the middle etching step provided after the roughening step, the electrolytic roughening can be performed more uniformly in the direct current electrolytic roughening step.

According to a sixth aspect of the present invention, the roughening treatment step is a mechanical roughening step in which at least one surface of the recycled aluminum plate is mechanically roughened prior to the pre-etching step. And a method for producing a lithographic printing plate support having:

In the method for producing the lithographic printing plate support, uniform and non-oriented grain can be formed on the surface of the recycled aluminum plate by the mechanical surface roughening treatment in the mechanical surface roughening step. The roughened surface formed in the roughening step is excellent in water retention. Therefore, the lithographic printing plate obtained by the above-mentioned production method, in which the plate-making layer is formed on the roughened surface of the lithographic printing plate support, is a lithographic printing plate that is very easy for the operator to print.

The invention according to claim 7 relates to a method for producing a support for a lithographic printing plate, which comprises performing an etching treatment in the pre-stage etching step so that a dissolved amount of the recycled aluminum plate becomes ¹ to 15 g / m ^2. .

According to the method for producing a support for a lithographic printing plate, a portion of the surface of the regenerated aluminum plate that is significantly protruded from the surroundings is preferentially dissolved and removed in the pre-stage etching step. Even if large irregularities such as scratches are present on the surface of the aluminum plate, the irregularities can be removed particularly effectively in the pre-stage etching treatment step.

The invention according to claim 8 is the production of a support for a lithographic printing plate, which is subjected to an etching treatment in the latter etching step so that the amount of the recycled aluminum plate dissolved is 0.01 to 5 g / m ^2. Regarding the method.

In the method for producing a lithographic printing plate support, fine irregularities formed on the surface of the regenerated aluminum plate in the DC electrolytic surface roughening treatment step appropriately remain after the post-etching treatment step.

Therefore, the lithographic printing plate having the lithographic printing plate support obtained by the above-mentioned production method and having the plate-making layer formed thereon is not particularly susceptible to severe ink stains and blank stains.

According to a ninth aspect of the present invention, the lithographic printing wherein the surface roughening step includes a pre-stage desmutting step in which the pre-stage etching step is followed by a desmutting treatment by bringing the recycled aluminum plate into contact with an acidic solution. The present invention relates to a method for manufacturing a plate support.

In the preceding etching step, since the regenerated aluminum plate is treated with an alkaline solution, the impurities contained in the regenerated aluminum plate are changed to hydroxides or the like to precipitate a so-called smut. The surface may change to a blackish color.

However, in the method for producing the lithographic printing plate support, as described above, the recycled aluminum plate is treated with the acidic solution in the pre-desmut step following the pre-etching step. The smut deposited on the surface in the pre-stage etching step is removed in the pre-stage desmut step.

Therefore, the recycled aluminum plate is
In the preliminary electrolytic surface roughening step or the direct current electrolytic surface roughening step which is performed subsequent to the preceding desmutting step, the electrolytic surface roughening is performed more uniformly, so that a particularly uniform surface roughened surface is obtained.

According to a tenth aspect of the present invention, the lithographic printing wherein the surface roughening step comprises a post-stage desmutting step in which the post-stage etching step is followed by a desmutting treatment by bringing the recycled aluminum plate into contact with an acidic solution. It is a method for producing a plate support.

As described in claim 9, smut is deposited even in the latter etching step,
The surface may change to a blackish color.

However, in the above manufacturing method, since the recycled aluminum plate is treated with the acidic solution in the latter desmutting step, the smut is effectively removed.

Therefore, the lithographic printing plate support obtained by the above-mentioned production method has not only a good appearance but also a uniform anodic oxide coating by being anodized in the anodizing step following the roughening step. Can be formed.

The invention according to claim 11 is the planographic printing wherein the roughening step comprises a middle desmutting step of desmutting the reclaimed aluminum plate in contact with an acidic solution subsequent to the middle etching step. The present invention relates to a method for manufacturing a plate support.

In the middle stage etching step, smut may be deposited on the surface as in the case of the front stage etching step and the second stage etching step, but the smut is easily removed by the middle stage desmutting process.

According to a twelfth aspect of the present invention, in the surface roughening step, the direct current electrolytic surface roughening step is performed subsequent to the front stage desmutting step, and the direct current electrolytic surface roughening step is performed in the front stage desmutting step. The present invention relates to a method for producing a support for a lithographic printing plate, which uses the acidic electrolytic solution used in 1. as an acidic solution.

In the method for producing the lithographic printing plate support, as described above, the acidic electrolytic solution used in the direct current electrolytic surface roughening step to be performed next in the preceding desmutting step is used.

Therefore, since it is possible to move to the next DC electrolytic surface roughening step without cleaning the recycled aluminum plate desmutted in the previous desmutting step, the former desmutting step and the DC electrolytic surface roughening step can be performed. It is possible to greatly simplify the equipment, such as omitting the washing equipment for washing the recycled aluminum plate in between. In addition, since the used acidic electrolyte that has been discharged as waste liquid in the DC electrolytic surface roughening step can be reused, the discharge amount of waste liquid can be greatly reduced.

According to a thirteenth aspect of the present invention, in the roughening step, the preliminary electrolytic surface roughening step is performed subsequent to the front stage desmutting step, and in the front stage desmutting step, the preliminary electrolytic surface roughening step is performed. The hydrochloric acid solution used in the acidification step is used as the acidic solution, and in the intermediate desmutting step, the lithographic printing plate support using the acidic electrolytic solution used in the DC electrolytic surface roughening step as the acidic solution. It relates to a manufacturing method.

The method for producing the lithographic printing plate support comprises a preliminary electrolytic surface roughening step, an intermediate etching step, an intermediate desmutting step, and a direct current electrolytic surface roughening step. The used acidic electrolyte is reused in the intermediate desmutting process.

Also in the above manufacturing method, the above-mentioned claim 12 is used.
For the same reason as described in the manufacturing method described in (1), it is possible to omit the cleaning equipment for cleaning the recycled aluminum plate between the intermediate desmutting step and the DC electrolytic surface roughening step. It can be simplified and the amount of waste liquid discharged can be significantly reduced.

According to a fourteenth aspect of the present invention, the content of aluminum in the recycled aluminum plate is 95 to 99.4.
The present invention relates to a method for producing a lithographic printing plate support having a weight percentage.

The content of aluminum in the recycled aluminum plate is usually in the range of 95 to 99.4% by weight. Claim 13 is a claim clarifying this.

According to a fifteenth aspect of the present invention, the recycled aluminum plate that has been roughened in the roughening step is anodized, and the roughened surface of the recycled aluminum plate is a roughened surface. The present invention relates to a method for producing a lithographic printing plate support having an anodizing step of forming an anodized film on a surface to be surfaced.

In the method for producing the lithographic printing plate support, since a highly hard and dense anodic oxide film is formed on the roughened surface of the recycled aluminum plate, the lithographic printing plate obtained by the above production method. A lithographic printing plate having excellent durability can be produced from the plate support.

According to a sixteenth aspect of the present invention, there is provided a lithographic printing plate support which is subjected to a hydrophilizing treatment for hydrophilizing the anodized film formed on the roughened surface of the recycled aluminum in the anodizing step. It relates to a manufacturing method.

The lithographic printing plate support obtained by the method for producing a lithographic printing plate support described above has excellent adhesion between the anodized film and the plate-making layer.

According to a seventeenth aspect of the present invention, in the anodizing step, a support for a lithographic printing plate is provided which performs a sealing treatment for sealing small holes in the anodized film formed on the roughened surface of the recycled aluminum. A method of manufacturing a body.

Since the lithographic printing plate support obtained by the method for producing a lithographic printing plate support described above has particularly few surface defects in the anodized film, it is particularly preferable to form a plate making layer on the roughened surface. A lithographic printing original plate having excellent resistance to severe ink stains can be obtained.

An eighteenth aspect of the present invention is a method for producing a lithographic printing plate support, wherein the acidic electrolytic solution used in the anodizing treatment is used as an acidic solution in the subsequent desmutting step.

In the above manufacturing method, after the subsequent desmut step, the recycled aluminum plate is not washed,
Since the process can be immediately transferred to the anodizing process, the cleaning equipment for cleaning the recycled aluminum plate can be omitted between the latter desmutting process and the anodizing process. Moreover, since the cleaning waste liquid is not discharged after the second-stage desmut treatment, the discharge amount of the waste liquid can be significantly reduced.

According to a nineteenth aspect of the present invention, after completion of at least one of the roughening step and the anodizing step, dry ice particles are jetted onto the roughened surface of the recycled aluminum plate to perform the roughening. The present invention relates to a method for producing a support for a lithographic printing plate, which comprises cleaning a surface to be surfaced.

The dry ice particles sprayed on the surface of the recycled aluminum plate collide with the surface of the recycled aluminum plate and at the same time sublime and disappear.

Therefore, in the method of manufacturing the lithographic printing plate support, the amount of waste water discharged in the washing step can be greatly reduced.

Further, since the processing solutions such as the alkaline solution, the acidic solution and the acidic electrolytic solution used in the above steps can be recovered without being diluted with the washing water, the processing solutions after the recovery can be easily reused. .

The invention described in claim 20 is according to claims 1 to 1.
Item 9. A lithographic printing plate support manufactured by the method according to any one of items 9.

Although the lithographic printing plate support was manufactured from a recycled aluminum plate, it had an average surface roughness R
a (JIS B0601-1994) is 0.3 to 0.6
μm, and the L ^* value shown in CIELAB space is 50.
˜95, ΔE ^* _ab is less than 2, and the roughened surface is excellent in uniformity. And almost no chatter marks are seen on the surface.

A lithographic printing plate prepared by making a lithographic printing original plate in which a lithographic printing plate is laminated on the roughened surface of the lithographic printing plate support is less likely to cause spot stains and blank stains.

The twenty-first aspect of the present invention relates to a lithographic printing original plate comprising a lithographic printing plate support according to the twentieth aspect, in which a plate-making layer is formed on the roughened surface.

The lithographic printing plate prepared by making the lithographic printing original plate described above has excellent printing durability without causing severe ink stain or blanc stain.

[0071]

BEST MODE FOR CARRYING OUT THE INVENTION 1. Recycled Aluminum Plate The recycled aluminum plate used in the present invention includes a sheet or plate material formed from recycled aluminum ingot such as scrap material and recycled material.

Examples of the scrap material include ingots obtained by remelting scrap of pure aluminum or aluminum alloy.

Examples of the recycled material include PS
Defective products that occur when manufacturing lithographic printing original plates such as plates,
Examples include used lithographic printing plates and recycled ingots made from recycled beverage cans.

The recycled aluminum ingot is made of Fe, S
Although various elements such as i, Cu, Mg, Mn, Zn, Cr, and Ti may be contained, the content of aluminum is preferably in the range of 95 to 99.4% by weight.

The Fe content is preferably 0.3 to 1.0% by weight. Fe is 0.1 to 0 even in new metal.
It is an element contained around 2% by weight, and the amount of solid solution in aluminum is small, and most of it remains as an intermetallic compound.
The recycled aluminum plate having a Fe content in the above range is:
It is preferable because cracks are less likely to occur during rolling and the cost is low. A more preferable Fe content is 0.5 to 1.0% by weight.

The Si content is preferably 0.15 to 1.0% by weight. Si is JIS2000 series, 4000
It is an element that is contained in large amounts in scrap materials of 6000 series materials and exists as a solid solution in aluminum or as an intermetallic compound.

When a recycled aluminum ingot containing an excessive amount of Si is heated, the solid solution Si may be precipitated as a simple substance Si. It is known that both simple substance Si and FeSi-based intermetallic compounds adversely affect the severe ink stain resistance.

However, if the Si content is within the above range, even if the intermetallic compound and simple substance Si are deposited on the surface, they can be sufficiently removed in the preceding desmutting step and the following desmutting step. There is no problem in terms of ink stainability, and it is also advantageous in terms of cost. A more preferable Si content is 0.3 to 1.
It is 0% by weight.

The Cu content is preferably 0.1 to 1.0% by weight. Cu is an element that is contained in large amounts in JIS 2000-series and 4000-series scraps, and is relatively easy to form a solid solution in aluminum. When the Cu content is within the above range, Cu deposited on the surface can be sufficiently removed in the preceding desmutting step and the following desmutting step, and it is also advantageous in terms of cost. A more preferable Cu content is 0.3 to 1.0% by weight.

The Mg content is preferably 0.1 to 1.5% by weight. Mg is JIS2000 series, 3000
It is an element that is contained in large amounts in scraps of 5,000 series, 5,000 series and 7,000 series materials. In particular, since it is contained in a large amount in can end materials, it is one of the major impurity metals contained in recycled materials.
Is one. Mg also relatively easily forms a solid solution in aluminum and forms an intermetallic compound with Si. However, in a recycled aluminum plate having a Mg content within the above range, the intermetallic compound can be easily removed in the preceding desmutting step and the following desmutting step, so that it is almost the same as a lithographic printing original plate prepared from new metal. A lithographic printing plate precursor having the above performance can be easily manufactured from a recycled aluminum plate. More preferable Mg content is 0.5 to 1.5% by weight.
And more preferably 1.0 to 1.5% by weight.

The Mn content is preferably 0.1 to 1.5% by weight. Mn is an element often contained in JIS 3000-based material scrap. Especially can body
It is one of the major impurity metals contained in recycled materials because it is contained in large quantities in recycled materials. Mn also relatively easily forms a solid solution in aluminum and forms an intermetallic compound with AlFeSi. However, if the Mn content is within the above range, Si
And Mg are preferable for the same reason as described above. A more preferable Mn content is 0.5 to 1.5% by weight.
And more preferably 1.0 to 1.5% by weight.

The Zn content is preferably 0.1 to 0.5% by weight. Zn is an element particularly contained in JIS 7000-based scrap in a large amount, and is relatively easy to form a solid solution in aluminum. However, if the Zn content is within the above range, it can be easily removed by the desmutting treatment, and therefore, a lithographic printing plate precursor having substantially the same performance as that of a new ingot is preferable because it can be obtained at a low cost. A more preferable Zn content is 0.3 to 0.5% by weight.

The Cr content is preferably 0.01 to 0.1% by weight. Cr is JIS 5000 series, 6000
Impurity metal contained in a small amount in 7000 series and 7000 series scraps. If the Cr content is within the above range, it can be sufficiently removed by the desmutting treatment, so that there is no problem in terms of severe ink stain resistance. It is also advantageous in terms of cost. More preferable Cr content is 0.05
Is 0.1% by weight.

The content of Ti is preferably 0.03 to 0.5% by weight. Ti is usually used as a grain refining material.
This is an element added in an amount of 01 to 0.04% by weight. JIS5
The scraps of 000 series, 6000 series, and 7000 series contain a relatively large amount of impurity metals. If the Ti content is within the above range, it is preferable for the same reason as described for Cr and Zn. A more preferable Ti content is 0.05 to 0.5% by weight.

As for the recycled aluminum plate, the surface thereof was polished to the extent that no scratch was visually observed, etched with hydrofluoric acid at room temperature, and had a width of 20 when observed under a microscope.
It is preferable that aluminum crystal grains of 0 μm are recognized on the entire surface.

The recycled aluminum plate is, for example, an ingot obtained by casting the recycled aluminum ingot by an ordinary method, appropriately subjected to rolling treatment or heat treatment, rolled to a thickness of 0.05 to 0.7 mm, and if necessary, It is manufactured by applying a flatness correction treatment.

As the method for producing the recycled aluminum plate, a DC casting method, a method in which at least one of soaking and annealing is omitted in the DC casting method, and a continuous casting method can be used.

The recycled aluminum plate may be a web which is a continuous strip-shaped sheet material or plate material, or may be a sheet-shaped sheet cut into a size corresponding to a lithographic printing original plate to be shipped as a product. Good. The thickness of the web and the sheet-shaped sheet is usually about 0.05 to 0.7 mm, preferably 0.1 to 0.5 mm.

2. Roughening step In the method for producing a lithographic printing plate support according to the present invention, the roughening step has at least a direct current electrolytic roughening step, but as a step prior to the direct current electrolytic roughening step,
It may have at least one of a mechanical surface roughening step, a pre-stage etching step, and a preliminary electrolytic surface roughening step. Further, as a step subsequent to the direct current electrolytic surface roughening step, a post-stage etching step is performed. You may have. further,
When the pre-electrolytic surface roughening step is included, the regenerated aluminum plate electrolytically surface-roughened in the pre-electrolytic surface roughening step is brought into contact with an alkaline solution, and the amount of dissolution of the regenerated aluminum plate is 0.01 to 1 g / At least one of an intermediate etching step of performing an etching treatment to obtain m ² and an intermediate desmutting step of performing a desmutting treatment by bringing a recycled aluminum plate etched in the intermediate etching step into contact with an acidic solution, the preliminary electrolytic surface roughening It may be provided between the step and the DC electrolytic surface roughening step.

In the manufacturing method having the pre-stage etching step, the pre-stage desmutting step may be provided immediately after the pre-stage etching step, and in the production method having the intermediate etching step, the recycled aluminum is provided immediately after the intermediate etching step. An intermediate desmutting step of smutting the plate with an acidic solution may be provided. Then, in the manufacturing method having the post-stage etching step, the post-stage desmutting step may be provided after the post-stage etching step.

Therefore, as the roughening step, for example, the following variations are provided: (roughening step 1) (1) pre-etching step, (2) pre-desmut step, (3)
DC electrolytic surface roughening step, (4) post-stage etching step, and
(5) Roughening step (roughening step 2) in which the latter desmutting step is sequentially performed (1) The former etching step, (2) The former desmutting step, (3)
Preliminary electrolytic surface roughening step, (4) intermediate etching step, (5) intermediate desmutting step, (6) DC electrolytic surface roughening step, (7) post-stage etching step, and (8) post-stage desmutting step Roughening step (roughening step 3) (1) mechanical roughening step, (2) pre-stage etching step, (3) pre-stage desmutting step, (4) DC electrolytic roughening step, (5) post-stage etching step, And (6) Roughening step (roughening step 4) in which the latter desmutting step is sequentially performed (1) Mechanical roughening step, (2) Pre-etching step, (3) Pre-desmutting step, (4) Pre-electrolysis Roughening step, (5) intermediate etching step, (6) intermediate desmutting step, (7) direct current electrolytic roughening step, (8) post-stage etching step, and (9) post-stage desmutting step to perform a roughening step sequentially And so on.

Each step in the roughening step will be described in detail below.

2-1 Direct Current Electrolytic Surface Roughening Treatment In the direct current electrolytic surface roughening step, as described above, the direct current is applied to the anode and the cathode which are alternately arranged and are immersed in the acidic electrolyte. Meanwhile, the recycled aluminum plate is passed through the vicinity of the anode and the cathode in the acidic electrolytic solution to perform electrolytic graining treatment.

In the DC electrolytic surface roughening step, for example, they are alternately arranged along the transfer surface which is the transfer path of the recycled aluminum plate, and immersed in the acidic electrolytic solution during the surface roughening treatment. Direct current electrolytic surface roughening provided with an anode and a cathode, and at least one of the anode and the cathode, and at the time of the roughening treatment, one or more electrolytic cells containing an acidic electrolytic solution. It is preferable to use a device.

In the DC electrolytic surface roughening device, it is preferable to dispose the anode and the cathode so that the distance between the anode and the cathode and the transport surface is 3 to 50 mm.

As the anode, a valve electrode such as titanium, tantalum or niobium, a clad electrode obtained by plating or clad with a metal belonging to the platinum group, and a ferrite electrode formed of ferrite can be used.

As the cathode, a metal electrode formed of a metal material selected from stainless steel and the valve metal can be used. Also, an electrode in which the valve metal is clad on a base material such as copper can be used.

The surface roughness of the surface of the cathode facing the recycled aluminum web W is 0.8-S (JI
Measured in accordance with S B 0601 and JIS B 0651. ) Or less, particularly preferably 0.4-S or less.

Further, the cathode preferably has a 20 ° specular gloss (JIS Z 8741) of 3 or more on the surface.

The surface roughness of said face of said cathode and 20 °
When the specular gloss is within the above range, it is possible to effectively prevent the electrolytic voltage from rapidly increasing during the electrolytic surface roughening treatment.

The cathode is formed by, for example, cold rolling, lapping finishing, surface grinding, surface milling, paper finishing, buffing, electrolytic polishing, chemical polishing, or liquid honing to obtain the surface roughness of the surface and a 20 ° mirror surface. It can be finished so that the glossiness falls within the above range.

In the DC electrolytic surface roughening device, the current density is in the range of 10 to 200 A / dm ² , and the quantity of electricity when the recycled aluminum plate is the anode is 100 to 100.
It is preferable to apply a direct current to the anode and the cathode so as to obtain 0 C / dm ² . The DC has a ripple rate of 2
It is preferably 0% or less.

As the acidic electrolyte, for example, a nitric acid aqueous solution whose main acid component is nitric acid, a hydrochloric acid aqueous solution whose main acid component is hydrochloric acid, and a sulfuric acid aqueous solution whose main acid component is sulfuric acid can be used.

The nitric acid aqueous solution has a nitric acid concentration of 1
A solution containing at least 20 g / liter of dilute nitric acid and at least one nitric acid compound such as aluminum nitrate, sodium nitrate, and ammonium nitrate in the range of 1 g / liter to a saturated concentration can be mentioned.

When the recycled aluminum plate contains elements such as iron, copper, manganese, nickel, titanium, magnesium and silicon, the nitric acid aqueous solution may contain these elements.

Among the aqueous nitric acid solutions, preferred ones are prepared by adding aluminum nitrate and ammonium nitrate to dilute nitric acid, the nitric acid concentration is 5 to 15 g / liter, and the aluminum ion concentration is 1 to 15 g / liter. An example is a nitric acid aqueous solution which is liter. The concentration of aluminum ions in the aqueous nitric acid solution is particularly preferably in the range of 4 to 14 g / liter.

The hydrochloric acid aqueous solution has a hydrochloric acid concentration of 1
Dilute hydrochloric acid in the range of up to 20 g / l can be used.
The aqueous hydrochloric acid solution may also contain one or more chlorides selected from aluminum chloride, sodium chloride, and ammonium chloride. The content of the chloride is preferably 1 g to the saturated amount / liter. Furthermore, Fe, Si, Cu, Mg, Mn, and Z are contained in the hydrochloric acid aqueous solution.
Ions of n, Cr, and Ti may be included.

The hydrochloric acid aqueous solution has a hydrochloric acid concentration of 5
Most preferred is a solution prepared by adding aluminum chloride to dilute hydrochloric acid so that the concentration of aluminum ion becomes 5 to 15 g / liter and the concentration of aluminum ion becomes 5 to 15 g / liter.

The sulfuric acid concentration in the aqueous sulfuric acid solution is 10 to 3
00 g / liter (1 to 30% by weight) is preferable, and the concentration of aluminum ions is 1 to 25 g / liter (0.
1 to 2.5% by weight) is preferable, and a range of 2 to 10 g / liter (0.2 to 1% by weight) is particularly preferable. Such an acidic electrolyte has, for example, a sulfuric acid concentration of 50 to 200 g.
It can be prepared by adding aluminum to 1 / liter of dilute sulfuric acid.

The liquid temperature of the acidic electrolyte is preferably 10 to 95 ° C, most preferably 20 to 50 ° C.

In the DC electrolytic surface roughening device, a flow of the acidic electrolytic solution may be formed in the electrolytic cell in a direction opposite or the same as the conveying direction of the recycled aluminum plate.

An example of the DC electrolytic surface roughening device is shown in FIG.

As shown in FIG. 1, a DC electrolytic surface roughening device 1
Reference numeral 00 denotes a direct current electrolytic surface roughening device for electrolytically roughening a recycled aluminum web W, which is an example of a recycled aluminum plate in the present invention, and includes a shallow box-shaped electrolytic cell 2 having an open upper surface and an electrolytic cell 2. The bottom surface is provided with anodes 8 and cathodes 10 that are alternately arranged in a row along the direction of arrow a.

The electrolytic cell 2 is further arranged in the vicinity of the end portion on the upstream side (hereinafter, simply referred to as “upstream side”) in the direction a, and the recycled aluminum web W is introduced into the electrolytic cell 2 and conveyed. Conveyor roller 4 for guiding along direction a
And the recycled aluminum web W, which is disposed in the vicinity of the end portion on the downstream side (hereinafter, simply referred to as “downstream side”) with respect to the direction a in the electrolytic cell 2 and conveyed in the electrolytic cell 2,
And a conveying roller 6 which is led out to the outside.

An acidic electrolytic solution supply pipe 12 for supplying the acidic electrolytic solution toward the upstream side is provided in the vicinity of the bottom surface on the downstream side of the transport roller 6 inside the electrolytic bath 2.

The electrolytic cell 2 is further divided into two sections on the upstream side of the conveying roller 4 by an overflow wall 14 which maintains the liquid surface of the acidic electrolytic solution inside the electrolytic cell 2 at a constant height. There is. An acidic electrolyte solution discharge conduit 16 for discharging the acidic electrolyte solution overflowing from the overflow wall 14 to the outside is provided on the bottom surface of the compartment on the upstream side of the overflow wall 14 in the electrolytic cell 2.

The anode 8 and the cathode 10 are rectangular plate-shaped electrodes and are arranged on the bottom surface of the electrolytic cell 2 so that the longitudinal direction thereof is perpendicular to the carrying direction a. The anode 8 is connected to the anode of a DC power supply (not shown), and the cathode 10 is connected to the cathode of the DC power supply.

When performing the electrolytic surface-roughening treatment in the DC electrolytic surface-roughening apparatus 100, the recycled aluminum web W is conveyed by the conveying rollers 4 to the electrolytic cell 2 as shown in FIG.
It is introduced into the inside of the electrolyzer 2 and is conveyed along the direction a in the vicinity of the bottom surface of the electrolyzer 2 and is guided out of the electrolyzer 2 by the conveying roller 6. Therefore, the direction a is
Can be rephrased as the transport direction a, which is the direction in which is transported.

On the other hand, the acidic electrolytic solution is supplied from the acidic electrolytic solution supply conduit 12 to the section of the electrolytic cell 2 downstream of the overflow wall 14, that is, the section where the recycled aluminum web W is conveyed, and the overflow wall is supplied. It overflows into the compartment upstream of the overflow wall 14 in the electrolytic cell 2 beyond 14 and is discharged to the outside from the acidic electrolyte discharge conduit 16. Therefore, the electrolytic cell 2
Inside, a flow of the acidic electrolytic solution occurs in the direction from the downstream side to the upstream side, in other words, in the direction opposite to the transport direction a.

On the surface of the recycled aluminum web W, a cathode reaction occurs when the recycled aluminum web W passes near the anode 8 and an anode reaction occurs when it passes near the cathode 10. While the web W is transported inside the electrolytic cell 2, the anode reaction and the cathode reaction are alternately repeated the same number of times on the surface of the recycled aluminum web W.

Therefore, it is possible to effectively prevent chatter marks from being formed on the surface of the recycled aluminum web W.

With respect to another example of the DC electrolytic surface roughening device,
The configuration is shown in FIG.

As shown in FIG. 2, DC electrolytic surface roughening device 1
02 is a long box-like shape whose upper part is opened and which has a partition wall 28.
The electrolytic cell 20 is divided into a plurality of anode chambers 22A and a cathode chamber 22B which are alternately provided so as to be adjacent to each other in the longitudinal direction, and are provided inside the anode chamber 22A and the cathode chamber 22B in the electrolytic cell 20. , A transport roller 24 for transporting the recycled aluminum web W along the transport direction a.

In the electrolytic cell 20, the anode chamber 22A is located on the most upstream side with respect to the carrying direction a, and the cathode chamber 22 is on the most downstream side.
It is divided so that B is located.

The transport roller 24 rotates in the clockwise direction in FIG. 2 with the recycled aluminum web W wound in a U shape, and transports the recycled aluminum web W from the right side to the left side in FIG. To do.

In the anode chamber 22A, the transport roller 24
The anode 30 is disposed below the and near the bottom surface. On the other hand, in the cathode chamber 22B, the cathode 32 is disposed near the bottom surface below the transport roller 24.

The anode 30 is similar to the anode 8 provided in the DC electrolytic surface roughening device 100 shown in FIG. 1, and is connected to the anode side terminal of a DC power supply (not shown). Similarly, the cathode 32 is similar to the cathode 10 included in the DC electrolytic surface roughening device 100 shown in FIG. 1, and is connected to the cathode side terminal of the DC power supply.

Guide rollers 26 for introducing the recycled aluminum web W drawn out from the anode chamber 22A or the cathode chamber 22B into the adjacent cathode chamber 22B or the anode chamber 22A are provided above the respective partition walls 28.

A liquid supply pipe 34 for supplying an acidic electrolyte is connected to the bottom surface of each of the anode chamber 22A and the cathode chamber 22B on the upstream side with respect to the transport direction a and on the downstream side with respect to the transport direction a. A drain pipe 36 for discharging the acidic electrolytic solution to the outside is connected.

As shown in FIG. 2, the recycled aluminum web W is formed in the electrolytic cell 20 in the most upstream anode chamber 22A.
Is introduced from above to the transport roller 2 in the anode chamber 22A.
4 is conveyed from the right side to the left side in FIG. 2, and is led out toward the upper side of the anode chamber 22A.

The recycled aluminum web W drawn from the anode chamber 22A is guided by the guide roller 26 to the anode chamber 2
It is introduced into the cathode chamber 22B adjacent to the downstream side of 2A.

The recycled aluminum web W introduced into the cathode chamber 22B is transported by the transport rollers 24 in the cathode chamber 22B, as in the case of the anode chamber 22A.
It is led out above 2B.

The recycled aluminum web W drawn out from the cathode chamber 22B is transferred to the second anode chamber 22A adjacent to the downstream side of the cathode chamber 22B by the second guide roller 26 adjacent to the downstream side of the guide roller 26. be introduced.

The recycled aluminum web W introduced into the most downstream cathode chamber 22B is
Is conveyed from the right side to the left side by the conveyance roller 24 and is led out above the cathode chamber 22B.

The recycled aluminum web W is stored in the anode chamber 22.
A cathode reaction occurs on the surface when passing through A, and an anode reaction occurs on the surface when passing through the cathode chamber 22B. Here, since the same number of the anode chambers 22A and the cathode chambers 22B are alternately provided in the electrolytic cell 20, while the recycled aluminum web W passes through the electrolytic cell 20, the anode reaction and the cathode reaction are alternately performed. It is repeated the same number of times.

Therefore, like the DC electrolytic surface roughening apparatus 100, the DC electrolytic surface roughening apparatus 102 does not have chatter marks on the surface of the recycled aluminum web W.

2-2 Pre-stage Etching Step, Middle-stage Etching Step, Post-stage Etching Step In the pre-stage etching step, the regenerated aluminum plate before electrolytic surface roughening in the DC electrolytic surface roughening step is brought into contact with an alkaline solution, Etching is performed.

The regenerated aluminum plate may be brought into contact with the alkali solution by, for example, continuously passing through the tank containing the alkali solution, immersing in the tank containing the alkali solution, and the alkali solution. Is sprayed on the surface of the recycled aluminum plate.

The etching amount is preferably in the range of 1 to 15 g / m ² . If the etching amount is within the above range, the oils and fats adhering to the surface of the recycled aluminum plate during the rolling are almost completely removed, so the water retention in the non-image area is high and the ink adheres to the non-image area. As a result, a lithographic printing original plate that does not cause a defective appearance such as so-called blanc stain can be obtained.

Examples of the alkali solution include solutions of caustic and alkali metal salts. The concentrations of caustic and alkali metal salt in the solution are
It can be determined based on the etching amount, but 1
It is preferably -50% by weight, and particularly preferably 10-35% by weight. When the alkaline solution contains aluminum ions, the concentration of the aluminum ions is 0.
The range of 01 to 10% by weight is preferable, and the range of 3 to 8% by weight is particularly preferable.

The temperature of the alkaline solution is preferably in the range of 20 to 90 ° C.

Examples of the caustic alkali include caustic soda and caustic potash.

Examples of the alkali metal salt include alkali metal silicates such as sodium metasilicate, sodium silicate, potassium metasilicate, and potassium silicate; alkali metal carbonates such as sodium carbonate and potassium carbonate; sodium aluminate and potassium aluminate. Alkali metal aluminates such as, alkali metal aldonates such as sodium gluconate and potassium gluconate,
In addition, alkali metal hydrogen phosphates such as sodium phosphate dibasic, potassium phosphate dibasic, sodium phosphate tribasic, potassium phosphate tribasic and the like can be mentioned. As the alkali solution, a caustic alkali solution and a solution of the caustic alkali and an alkali metal aluminate are particularly preferable from the viewpoint of high etching rate and low cost.

The etching treatment can be carried out by using an etching apparatus usually used for the etching treatment of the recycled aluminum plate. The etching device has a tank for storing an alkaline solution, a type in which the recycled aluminum plate is immersed in the tank, and a spray nozzle, and the spray nozzle extends from the spray nozzle toward the recycled aluminum plate. An example is one in which an alkaline solution is sprayed. The etching apparatus may be a batch type or a continuous type.

In the middle etching step, an alkali solution is brought into contact with the recycled aluminum plate electrolytically surface-roughened in the preliminary electrolytic surface-roughening step to be described later, and in the latter-stage etching step, the electrolytic surface-roughening in the DC electrolytic surface-roughening step is carried out. An etching treatment can be performed by bringing an alkali solution into contact with the recycled aluminum plate that has been subjected to the chemical treatment.

As the alkaline solution in the middle etching step and the second etching step, the same caustic and alkali metal salt solutions as those mentioned in the previous etching step can be used.

The concentration of the caustic alkali and the alkali metal salt in the alkaline solution is preferably 0.01 to 30% by weight, and the temperature is preferably 20 to 90 ° C.

The etching amount is preferably in the range of 0.01 to 5 g / m ² , and in the middle etching step, the etching amount is 0.
Particularly preferably in the range of 05~1g / m ^2, in the subsequent etching step, the range of 0.05 to 2 g / m ² is particularly preferred.

The etching process in the middle stage etching process and the second stage etching process can be performed using the same etching apparatus as described in the previous stage etching process.

2-3 First Desmut Step, Middle Desmut Step, Second Desmut Step When the recycled aluminum plate is etched in the preceding etching step, the middle etching step, and the subsequent etching step, impurities in the recycled aluminum plate are oxidized. Since it changes into a substance and black smut of black to dark gray is deposited on the surface, it is preferable to perform desmut treatment to remove the smut on the surface.

The desmutting treatment can be carried out by immersing the regenerated aluminum plate after the etching treatment in an acidic solution or by passing it through the acidic solution. Moreover, you may spray the said acidic solution using a spray nozzle.

The acidic solution contains hydrochloric acid, nitric acid, or sulfuric acid as a main acid component, the concentration of the acid component is 0.5 to 5% by weight, and the aluminum ion is 0.001 to 5% by weight. %, And the liquid temperature is 25 ~
A 90 ° C. aqueous solution is preferred.

In the preceding desmutting step performed immediately after the preceding etching step and the intermediate desmutting step performed immediately after the intermediate etching step, in the direct current electrolytic graining step or the preliminary electrolytic graining step that is performed subsequently. It is preferable to perform desmutting treatment using the discharged acidic electrolyte.

In the subsequent desmutting process which is performed immediately after the latter etching process, the sulfuric acid solution discharged in the anodizing process described later is used to obtain a liquid temperature of 25 to 90 ° C.
It is preferable to carry out desmut treatment.

The acidic electrolytic solution discharged in the direct current electrolytic surface roughening step, the preliminary electrolytic surface roughening step, or the anodizing step that is subsequently performed in the preceding stage desmutting step, the middle stage desmutting step, and the latter stage desmutting step. Alternatively, by using a sulfuric acid solution, the amount of waste liquid discharged in the production of the lithographic printing plate support can be greatly reduced. Further, after the completion of the former desmutting step and the latter desmutting step, it is possible to move to the next step without performing a water washing treatment, so that the facility can be greatly simplified.

In the latter desmutting process, instead of using the waste solution of the sulfuric acid solution, the concentration of sulfuric acid was 1%.
00-600 g / liter, particularly preferably 250-5
You may use the sulfuric acid solution which is 00 g / liter and has a liquid temperature of 60 to 90 ° C.

In both of the former desmutting step and the latter desmutting step, the time for contacting the regenerated aluminum plate with the acidic solution is preferably 1 to 180 seconds.

2-4 Preliminary Electrolytic Surface Roughening Step In the preliminary electrolytic surface roughening step, the regenerated aluminum plate is subjected to electrolytic surface roughening treatment in an aqueous hydrochloric acid solution with alternating current or direct current.

The concentration of hydrochloric acid in the hydrochloric acid aqueous solution is 1 to 2
The range of 0 g / liter is preferable. It may also contain one or more chlorides selected from aluminum chloride, sodium chloride and ammonium chloride. The content of the chloride is preferably 1 g to the saturated amount / liter.
Further, in the hydrochloric acid aqueous solution, Fe, Si, Cu, M
Ions of g, Mn, Zn, Cr, and Ti may be included.

The hydrochloric acid aqueous solution has a hydrochloric acid concentration of 5
~ 15g / l, aluminum ion concentration is 5 ~
15g / l, ammonium ion concentration is 10
Most preferred is a solution of aluminum chloride and ammonium chloride added to dilute hydrochloric acid so as to give 300 ppm.

The liquid temperature is preferably 10 to 95 ° C, and 30 to
Most preferred is 50 ° C.

In the preliminary electrolytic surface roughening step, a direct current may be applied to the recycled aluminum plate, but an alternating current is preferably applied. Examples of the alternating current include currents having a waveform such as a sine wave, a rectangular wave, a triangular wave, and a trapezoidal wave. Among these, a rectangular wave current having a rectangular waveform and a trapezoidal current having a trapezoidal waveform are preferable. In addition, in the preliminary electrolytic surface roughening step, a current in which alternating current and direct current are superposed may be applied.

The frequency of the alternating current is preferably 40 to 120 Hz, particularly 5 from the viewpoint of the cost of manufacturing the power supply device.
The range of 0 to 60 Hz is preferable.

Further, the ratio Qc / Qa of the quantity of electricity when the aluminum plate becomes the anode, that is, the quantity of electricity Qa at the anode and the quantity of electricity when it becomes the cathode, that is, the quantity of electricity Qc at the cathode is 0.9.
It is preferable for it to be in the range of 1 because uniform pits can be formed on the surface of the aluminum plate. In particular, it is preferable that the above Qc / Qa is in the range of 0.95 to 0.99. When performing the electrolytic surface roughening treatment in an AC electrolytic cell having an auxiliary electrode for shunting the anode current of the main electrode,
JP-A-60-43500 and JP-A-1-520.
As described in Japanese Patent Publication No. 98, the ratio Qc / Qa can be controlled by controlling the current value of the anode current shunted to the auxiliary electrode.

The duty of the alternating current used in the electrolytic surface roughening treatment is 0.5 because of the fact that the surface of the aluminum plate is uniformly roughened and because of the convenience of manufacturing the power supply device.
Is most preferred. The term “duty” as used in the present invention means ta / T when the time during which the aluminum plate undergoes an anodic reaction (anode reaction time) is ta in the cycle T of the alternating current.

On the surface of the recycled aluminum plate, an oxide film mainly composed of aluminum hydroxide is produced during the cathode reaction, and further dissolution or destruction of the oxide film may occur. Then, when the oxide film is dissolved or destroyed, the portion where the dissolution or destruction is caused becomes the starting point of the pitting reaction during the anode reaction of the next recycled aluminum plate. Therefore, the selection of the duty of the alternating current is particularly important in terms of performing uniform electrolytic graining treatment.

The time tp until the current value of the AC current reaches a positive or negative peak from 0 is usually 0.01 to 0.01 when the AC current is a trapezoidal wave current.
The range is 6 milliseconds, the range of 0.05 to 5 milliseconds is preferable, and the range of 0.8 to 2 milliseconds is particularly preferable. When the time tp is within the range, more uniform honeycomb pits are formed on the surface of the recycled aluminum plate.

The amount of electricity from the start to the end of the electrolytic surface roughening treatment is generally in the range of 1 to 300 C / dm ² when the recycled aluminum plate is the anode, and ranges preferably 100C / dm ^2, in particular in the range of 25~75C / dm ² is preferred.

With respect to the peak current Iap on the anode cycle side and the peak current Icp on the cathode cycle side in the AC current, the total amount of electricity from the start to the end of the electrolytic graining treatment is within the above range. However, both are preferably 1 to 100 A / dm ² . Further, Icp / Iap is preferably in the range of 0.9 to 1.0.

In the electrolytic surface roughening treatment, when a rest period in which no AC current flows is provided in one AC electrolytic cell, the length of the rest period should be 0.001 second to 0.6 second or less. This is preferable because the honeycomb pits are uniformly formed on the entire surface of the recycled aluminum plate. When using two or more alternating current electrolytic cells arranged in series, the time during which the regenerated aluminum plate is not energized between one alternating current electrolytic cell and another alternating current electrolytic cell is 10 seconds or less, particularly 5 seconds or less. It is preferable that

As an alternating current electrolytic cell which can be used in the electrolytic surface roughening treatment, a vertical type, a flat type described in JP-B-61-30036, and JP-A-8-300843 are used.
Various types of alternating current electrolytic cells, such as the radial type electrolytic cell described in Japanese Patent Publication (KOKAI), are mentioned, but the radial type alternating current electrolytic cell is particularly preferable.

Further, two radial type AC electrolysis cells are used in series, one on the upstream side is an AC electrolysis cell for the former stage, and one on the downstream side is an AC electrolysis cell for the latter stage. Electrolytic surface roughening devices are also preferred.

An example of the AC electrolytic surface roughening device is shown in FIG.

As shown in FIG. 3, the AC electrolysis surface roughening device 104 is housed inside the AC electrolysis tank main body 42 and the AC electrolysis tank main body 42 in which the hydrochloric acid aqueous solution is stored. A feed roller 4 which is rotatably arranged about an axis extending in the direction of the arrow and feeds the recycled aluminum web W in the direction of arrow a, that is, from left to right in FIG.
4 and.

The inner wall surface of the AC electrolysis cell main body 42 is formed in a substantially cylindrical shape so as to surround the feed roller 44, and the semi-cylindrical main poles 46A and 46B sandwich the feed roller 44 on the inner wall surface. It is provided. Main poles 46A and 46B
Is divided into a plurality of small electrodes, and an insulating spacer is interposed between the respective electrodes. The small electrodes can be formed of, for example, graphite or metal, and the spacers can be formed of, for example, vinyl chloride resin. The spacer has a thickness of 1 to 10 mm.
Is preferred. Further, although omitted in FIG. 3, the main pole 4
In both 6A and 46B, each of the electrodes divided by the spacer is connected to an AC power supply AC.

At the upper part of the AC electrolysis tank 40, an opening 42A for introducing / drawing the recycled aluminum web W into / from the AC electrolysis tank main body 42 is formed. A liquid supply nozzle 48A for replenishing the AC electrolytic cell body 42 with a hydrochloric acid aqueous solution is provided near the opening 42A in the AC electrolytic cell body 42. On the other hand, the main pole 46A and the main pole 46 of the AC electrolytic cell body 42
Similarly, a liquid supply nozzle 48B for replenishing the AC electrolytic cell body 22 with the hydrochloric acid aqueous solution is provided between the same and B.

Opening 42 above AC electrolysis cell 40
In the vicinity of A, an upstream guide roller 50A for guiding the recycled aluminum web W into the AC electrolytic cell body 42, and a group of downstream sides for guiding the electrolytically treated recycled aluminum web W in the AC electrolytic cell body 42 to the outside. Guide roller 50B
And are provided.

In the AC electrolysis tank 40, an overflow tank 52 is provided adjacent to the downstream side of the AC electrolysis tank main body 42. The overflow tank 52 has a function of temporarily storing the hydrochloric acid aqueous solution overflowing from the AC electrolysis tank main body 42 and keeping the liquid surface height of the hydrochloric acid aqueous solution in the AC electrolysis tank main body 42 constant.

An auxiliary electrolysis tank 54 is provided downstream of the overflow tank 52.
Is provided. The auxiliary electrolysis tank 54 is shallower than the AC electrolysis tank main body 42, and has a bottom surface 54A formed in a planar shape. An auxiliary liquid supply nozzle 58 for supplying a hydrochloric acid aqueous solution to the auxiliary electrolysis tank 54 is provided near the upstream side wall surface of the auxiliary electrolytic bath 54, and an aqueous hydrochloric acid solution supplied from the auxiliary liquid supply nozzle 58 is provided near the upstream side wall surface. An overflow weir 54B is provided which overflows and holds the liquid surface of the hydrochloric acid aqueous solution in the auxiliary electrolysis tank 54 at a constant height. A plurality of columnar auxiliary electrodes 56 are provided on the bottom surface 54A.

The auxiliary electrode 56 is preferably formed of a highly corrosion-resistant metal such as platinum or ferrite, or may be plate-shaped.

The auxiliary electrode 56 is connected in parallel to the main pole 46B on the side of the AC power supply AC to which the main pole 46B is connected, and in the middle, the thyristor Th1 is connected to the main pole 46B of the AC power supply AC at the time of ignition. It is connected so that a current flows from the side to the auxiliary electrode 56.

The side of the AC power supply AC to which the main pole 46A is connected also has the auxiliary electrode 5 through the thyristor Th2.
Connected to 6. The thyristor Th2 is also connected so that a current flows from the side to which the main pole 46A of the AC power source AC is connected toward the auxiliary electrode 56 at the time of ignition.

When either of the thyristors Th1 and Th2 is fired, the anode current flows through the auxiliary electrode 56. Therefore, by controlling the phase of the thyristors Th1 and Th2, the current value of the anode current flowing through the auxiliary electrode 56 can be controlled, and therefore Qc / Qa can also be controlled.

The operation of the electrolytic surface roughening device 104 will be described below.

From the left side in FIG. 3, the aluminum plate W guided to the AC electrolytic cell 40 is first guided to the electrolytic cell body 42 by the upstream guide roller 50A. Then, it is fed from the left side to the right side in FIG. 1 by the feed roller 44 and guided into the auxiliary electrolytic bath 54 by the downstream guide roller 50B.

AC electrolytic cell body 42 and auxiliary electrolytic cell 54
In the inside of the aluminum plate W, due to the alternating current applied to the main poles 46A and 46B and the anode current applied to the auxiliary electrode 56, the aluminum plate W is heated by the main poles 46A and 46B.
The surface on the side facing B is roughened to form almost uniform honeycomb pits.

2-5 Mechanical Surface Roughening Treatment In the mechanical surface roughening process, a synthetic resin hair made of synthetic resin such as nylon (trade name), propylene, vinyl chloride resin, etc. is formed on the surface of the cylindrical body. It is common to perform a mechanical surface roughening treatment in which one or both surfaces of the recycled aluminum plate are rubbed mechanically by a roller-shaped brush having a large number of brush bristles planted therein. In the mechanical roughening treatment, the recycled aluminum plate may be roughened by using a polishing roller which is a roller having a polishing layer on the surface thereof, instead of the roller brush. When a roller brush is used, mechanical surface roughening treatment can be performed while spraying an abrasive slurry liquid described later on the rotating roller brush.

The length of the bristles in the roller-shaped brush can be appropriately determined according to the outer diameter of the roller-shaped brush and the diameter of the body, but generally 10 to 10
The range is 0 mm.

Silica sand and pumice stone are used as the abrasive. Silica sand is harder and less likely to break than pumice stone, so that the surface of the recycled aluminum plate can be marked very efficiently, which is preferable.

The average particle size of the abrasive is 3 to 5 from the viewpoint that the roughening efficiency is high and the graining pitch can be narrowed.
The range of 0 μm is preferable, and the range of 6 to 45 μm is particularly preferable. And, in the case of silica sand, the range of 20 to 25 μm is most preferable, and in the case of pumice stone, it is 40 to
The range of 45 μm is most preferable. The average particle size of the abrasive is 5 when the ratio of the abrasive having a certain particle size to the total volume of the abrasive is accumulated with respect to the particle size.
It can be defined as a particle size of 0% by weight.

The abrasive can be used, for example, as a polishing slurry liquid suspended in water. In addition, a thickener, a dispersant such as a surfactant, and a preservative may be added to the polishing slurry liquid.

3. Anodizing Treatment Step In the present invention, it is preferable to subject the recycled aluminum plate to a surface roughening treatment and then anodizing treatment.

In the anodizing treatment step, the recycled aluminum plate subjected to the surface roughening treatment is anodized according to a conventional method.

In the anodizing treatment, for example, in an acidic electrolytic solution containing at least one of sulfuric acid, phosphoric acid, oxalic acid, chromic acid, and amidosulfonic acid as an acid component,
Direct current, pulsating current, or alternating current is applied to the recycled aluminum plate.

The conditions of the anodizing treatment cannot be unconditionally specified because it varies depending on the composition of the acidic electrolytic solution used, but generally, the concentration of the acid component in the acidic electrolytic solution is 1 to 80% by weight. The range is preferable, and the temperature of the acidic electrolytic solution is preferably in the range of 5 to 70 ° C. The current density is preferably in the range of 1 to 60 A / dm ² , and the voltage is preferably in the range of 1 to 100V. Electrolysis time is 10
A range of 300 seconds is suitable.

As the above-mentioned acidic electrolyte, Japanese Patent Laid-Open No. 54-1 is used.
As described in 2853 and JP-A-48-45303, those containing sulfuric acid as an acid component are preferable.

The concentration of sulfuric acid in the acidic electrolytic solution is 10-
300 g / liter (1 to 30% by weight) is preferable, and the concentration of aluminum ions is preferably 1 to 25 g / liter (0.1 to 2.5% by weight), particularly 2 to 10 g.
/ Liter (0.2 to 1% by weight) is preferable. Such an acidic electrolyte has, for example, a sulfuric acid concentration of 50 to 2
It can be prepared by adding aluminum to 00 g / liter of dilute sulfuric acid.

When anodizing treatment is performed in the acidic electrolytic solution containing sulfuric acid, direct current or alternating current may be applied to the regenerated aluminum plate.

[0199] When applying a DC to the reproduction aluminum plate, the current density is preferably in the range of 1 to 60 A / dm ^2, in particular in the range of 5 to 40 A / dm ² is preferred.

When performing anodizing treatment continuously,
As partially concentrated current playback aluminum plate so-called "burnt" no, the beginning of the anodic oxidation treatment, current flows at a low current density of 5~10A / dm ^2, the anodic oxidation treatment As it progresses, 30-50 A / dm ² ,
Alternatively, it is preferable to increase the current density more than that.

In the above case, it is also preferable that the regenerated aluminum plate is subjected to anodizing treatment by a liquid power feeding system in which power is fed through the acidic electrolytic solution. Further, as an electrode for supplying power to the recycled aluminum plate, an electrode formed of lead, iridium oxide, platinum, ferrite or the like can be used. Among the above-mentioned electrodes, an electrode mainly formed of iridium oxide and an electrode in which the surface of the base material is coated with iridium oxide are preferable. As the base material coated with iridium oxide, the valve metal described in the DC electrolytic surface roughening step is preferable, and titanium and niobium are particularly preferable. Since the valve metal has a relatively large electric resistance, the valve metal may be clad on the surface of a core material made of copper to form the base material. When the valve metal is clad on the surface of a core material made of copper, it is difficult to produce a base material having an excessively complicated shape. The substrate may be assembled by cladding the metal and then combining the parts.

In the anodizing treatment, the amount of anodized film is 1 to 5
From the viewpoint of printing durability of the planographic printing plate, it is preferable to carry out so as to be g / m ² . Further, the difference in the amount of anodized film between the central part and the vicinity of the edge of the recycled aluminum plate is 1 g / m.
It is preferable to carry out so as to be ² or less.

In the anodizing treatment, the regenerated aluminum plate on which the anodizing film is formed is further immersed in an aqueous solution of an alkali metal silicate such as sodium silicate and potassium silicate for hydrophilic treatment, or hydrophilic treatment. It is preferable that a hydrophilic vinyl polymer or a hydrophilic compound is applied to form a hydrophilic undercoat layer.

The hydrophilic treatment with an aqueous solution of an alkali metal silicate such as sodium silicate and potassium silicate is described in US Pat.
714,066 and U.S. Pat. No. 3,181,
It can be carried out according to the method and procedure described in Japanese Patent Application No. 461.
9-101651 and JP-A-60-14949.
It can be carried out according to the conditions and procedures described in JP-A-1. Examples of the hydrophilic vinyl polymer include polyvinyl sulfonic acid and vinyl polymerizable compounds having a sulfonic acid group having a sulfonic acid group such as p-styrene sulfonic acid, and ordinary vinyl polymerizable compounds such as (meth) acrylic acid alkyl ester. And the hydrophilic compound includes a compound having at least one of an NH ₂ group, a —COOH group, and a sulfone group.

Further, the recycled aluminum plate having the anodized film formed thereon may be brought into contact with boiling water, hot water, or steam to carry out a sealing treatment for sealing the small holes in the anodized film.

4. Lithographic printing original plate The roughened surface of the lithographic printing plate support produced by the production method of the present invention, a laser exposed by a laser beam such as a visible light exposure type plate-making layer or infrared laser beam which is exposed with normal visible light A lithographic printing plate precursor can be produced by forming a plate-making layer such as an exposure type plate-making layer.

On the surface of the plate-making layer, a matte layer, which is a minute hemispherical projection, can be further formed on the entire surface. The amount of the matte layer is preferably 0.1 to 1 g / m ² .

Further, by providing a back coat layer on the surface of the support for the lithographic printing plate opposite to the roughened surface, a plate-making layer in the lithographic printing original plate as a lower layer and the lithographic printing plate laminated on the lithographic printing original plate are provided. It is prevented that the surface opposite to the roughened surface of the printing original plate is rubbed and the plate making layer of the lower planographic printing original plate is damaged.

The back coat layer is described in JP-A-6-
The thing containing the polymer of 32115 and the surfactant is mentioned, Moreover, thickness is 0.01-8micro.
About m is preferable.

4-1 Visible Light Exposure Type Plate Making Layer The visible light exposure type plate making layer can be formed of a composition containing a photosensitive resin and, if necessary, a colorant and the like.

Examples of the photosensitive resin include a positive photosensitive resin which becomes soluble in a developing solution when exposed to light, and a negative photosensitive resin which becomes insoluble in a developing solution when exposed to light.

Examples of the positive type photosensitive resin include a combination of a diazide compound such as a quinonediazide compound and a naphthoquinonediazide compound with a phenol resin such as a phenol novolac resin and a cresol novolac resin.

On the other hand, as the negative photosensitive resin, a diazo resin such as a condensation product of an aromatic diazonium salt and an aldehyde such as formaldehyde, an inorganic acid salt of the diazo resin,
And a diazo compound such as an organic acid salt of the diazo resin,
Combination with a binder such as (meth) acrylate resin, polyamide resin, and polyurethane, and (meth)
Examples include combinations of vinyl polymers such as acrylate resins and polystyrene resins, vinyl polymerizable compounds such as (meth) acrylic acid esters and styrene, and photopolymerization initiators such as benzoin derivatives, benzophenone derivatives, and thioxanthone derivatives.

As the colorant, in addition to usual dyes,
It is possible to use an exposed coloring dye that develops color upon exposure, and an exposure decolorizable dye that becomes almost or completely colorless upon exposure. Examples of the light-exposure coloring dyes include leuco dyes. On the other hand, examples of the exposure decolorizable dyes include triphenylmethane dyes, diphenylmethane dyes, oxazine dyes, xanthene dyes, iminonaphthoquinone dyes, azomethine dyes, and anthraquinone dyes.

The visible light exposure type plate making layer can be formed by applying a photosensitive resin solution containing the photosensitive resin and the colorant mixed in a solvent and drying the solution.

Examples of the solvent used for the photosensitive resin solution include a solvent which dissolves the photosensitive resin and has some volatility at room temperature. Specific examples include alcohol solvents and ketones. Examples thereof include system solvents, ester solvents, ether solvents, glycol ether solvents, amide solvents, and carbonate ester solvents.

As the alcohol solvent, ethanol,
Propanol, butanol, etc. are mentioned.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, and diethyl ketone.

Examples of the ester solvent include ethyl acetate, propyl acetate, methyl formate, ethyl formate and the like.

Examples of the ether solvent include tetrahydrofuran and dioxane, and examples of the glycol ether solvent include ethyl cellosolve, methyl cellosolve, and butyl cellosolve.

Examples of the amide solvent include dimethylformamide and dimethylacetamide.

Examples of the carbonate ester solvent include ethylene carbonate, propylene carbonate, diethyl carbonate, dibutyl carbonate and the like.

The method of applying the photosensitive resin solution is as follows:
Examples of the conventionally known method include a spin coating method, a wire bar method, a dip coating method, an air knife coating method, a roll coating method, and a blade coating method.

4-2 Laser Exposure Type Plate Making Layer As the laser exposure type plate making layer, a negative type laser plate making layer in which a portion irradiated with laser light remains, a positive type laser plate making layer in which a portion irradiated with laser light is removed, The main examples thereof include a photopolymerization type laser plate making layer which undergoes photopolymerization when irradiated with a laser beam.

A. Negative-type laser plate-making layer The negative-type laser plate-making layer is (A) an acid precursor that decomposes by heat or light to generate an acid, and (B) the acid precursor (A) decomposes and crosslinks with an acid. Acid crosslinkable compound,
It can be formed from a negative type laser plate making layer forming liquid obtained by dissolving or suspending (C) an alkali-soluble resin, (D) an infrared absorber, and (E) a compound containing a phenolic hydroxyl group in an appropriate solvent.

Examples of the acid precursor (A) include compounds such as iminophosphate compounds which decompose by ultraviolet light, visible light or heat to generate sulfonic acid. Besides, compounds generally used as a photocationic polymerization initiator, a photoradical polymerization initiator, a photochromic agent or the like can also be used as the acid precursor (A).

The acid-crosslinkable compound (B) is an aromatic compound having at least one of an alkoxymethyl group and a hydroxyl group, a compound having an N-hydroxymethyl group, an N-alkoxymethyl group, or an N-acyloxymethyl group, And epoxy compounds.

Examples of the alkali-soluble resin (C) include novolak resins and polymers having a hydroxyaryl group in the side chain such as poly (hydroxystyrene).

As the infrared absorbent (D), 760 nm
Dyes and pigments that absorb infrared rays of up to 1200 nm are listed, and specifically, black pigments, red pigments, metal halide pigments, phthalocyanine pigments, and azo dyes, anthraquinone dyes, phthalocyanine dyes that absorb infrared rays of the above wavelengths, Examples include cyanine dyes.

As the phenolic hydroxyl group-containing compound (E), a compound of the general formula (R ₁ -X) _n -Ar- (OH) _m (R ₁ is
It is a C6-C32 alkyl group or alkenyl group, X is an end bond, O, S, COO, or CONH, Ar is an aromatic hydrocarbon group, an alicyclic hydrocarbon group,
Alternatively, it is a heterocyclic group, and both n and m are natural numbers of 1 to 3. ). The compound shown by these is mentioned. Specific examples of the compound include alkylphenols such as nonylphenol.

A plasticizer may be further added to the negative type laser plate making layer forming liquid.

B. Positive type laser plate making layer The positive type laser plate making layer is (F) an alkali-soluble polymer,
It can be formed by a positive type laser plate making layer forming liquid in which (G) an alkali dissolution inhibitor and (H) an infrared absorber are dissolved or suspended in an appropriate solvent.

As the alkali-soluble polymer (F), for example, phenol resin, cresol resin, novolac resin, pyrogallol resin, and phenol type polymer having a phenolic hydroxyl group such as poly (hydroxystyrene), at least a part of monomer units are used. Sulfonamide group-containing polymer that is a polymer having a sulfonamide group, active imide group-containing polymer obtained by homopolymerization or copolymerization of a monomer having an active imide group such as N- (p-toluenesulfonyl) (meth) acrylamide group, etc. Can be used.

Examples of the alkali dissolution inhibitor (G) include compounds that react with the alkali-soluble polymer (F) by heating or the like to reduce the alkali-solubility of the alkali-soluble polymer (F). Examples thereof include sulfone compounds, ammonium salts, sulfonium salts, and amide compounds. For example, alkali-soluble polymer (F)
When the above novolac resin is used as, the cyanine dye, which is one of the sulfone compounds, is preferable as the alkali dissolution inhibitor (G).

Examples of the infrared absorbent (H) include squarylium dyes, pyrylium dyes, carbon black, insoluble azo dyes, anthraquinone dyes, and the like, 750 to 120.
Examples include dyes, dyes, and pigments having an absorption region in the infrared region of 0 nm and having a light / heat conversion ability.

C. Photopolymerizable Laser Plate-Making Layer The photopolymerizable laser plate-making layer can be formed with a photopolymerizable laser plate-making layer forming liquid containing (I) a vinyl polymerizable compound having an ethylenically unsaturated bond at the molecular end. If necessary, the photopolymerization laser plate-making layer forming liquid may contain (J) a photopolymerization initiator and (K) a sensitizer.

Examples of the vinyl polymerizable compound (I) include an ethylenically unsaturated carboxylic acid polyester which is an ester of an ethylenically unsaturated carboxylic acid such as (meth) acrylic acid, itaconic acid and maleic acid and an aliphatic polyhydric alcohol. Valent ester,
Examples thereof include ethylenically unsaturated carboxylic acid polyvalent amides such as methylenebis (meth) acrylamide and xylylene (meth) acrylamide, which are composed of the ethylenically unsaturated carboxylic acid and polyvalent amine.

Other examples of the vinyl polymerizable compound (I) include aromatic vinyl compounds such as styrene and α-methylstyrene, and ethylenically unsaturated carboxylates such as methyl (meth) acrylate and ethyl (meth) acrylate. Acid monoesters and the like can also be used.

As the photopolymerization initiator (J), a photopolymerization initiator usually used for photopolymerization of vinyl monomers can be used.

Examples of the sensitizer (K) include titanocene compounds, triazine compounds, benzophenone compounds, benzimidazole compounds, cyanine dyes, merocyanine dyes, xanthene dyes and coumarin dyes.

Solvents used for the negative type laser plate making layer forming liquid, the positive type laser plate making layer forming liquid, or the photopolymerization type laser plate making layer forming liquid, and the negative type laser plate making layer forming liquid, positive type laser plate making layer The coating method of the forming liquid or the photopolymerization type laser plate making layer forming liquid is the same as the solvent and the coating method described in "4-1 Visible light exposure type plate making layer".

When forming the photopolymerization type laser plate making layer, a silicone compound having a reactive functional group such as a partially decomposed silane compound obtained by partially decomposing a silane compound with water, alcohol or carboxylic acid. It is preferable to pretreat the roughened surface of the lithographic printing plate support because the adhesion between the lithographic printing plate support and the photopolymerizable laser plate making layer is improved.

4-3 Plate Making The lithographic printing original plate is cut into an appropriate size if necessary, exposed and developed to make a plate.

In the case of a lithographic printing plate precursor having a photosensitive plate-making layer, it can be prepared by superposing a transparent film on which a printed image is formed, exposing it to ordinary visible light, and then developing it.

In the case of a lithographic printing original plate having a laser exposure type plate making layer, it can be made by irradiating with various laser beams to directly write the print image, exposing it, and then developing.

[0246]

EXAMPLES The present invention will be described in more detail below with reference to examples.

[Example 1] A molten material of a recycled material having the composition shown in Table 1 was degassed, filtered, and then cast by a usual method to obtain an ingot.

[0248]

[Table 1]

Both sides of the obtained ingot are chamfered to have a thickness of 500.
mm, width 1000 mm, length 3500 mm, soaking treatment was performed, and hot rolled and cold rolled to obtain a regenerated aluminum plate having a thickness of 1.5 mm.

[0250] The recycled aluminum plate was subjected to 1 at 360 ° C.
Intermediate annealing treatment was performed for a period of time, finish cold rolling was performed at a reduction rate of 80%, and further finish annealing treatment was performed to obtain a regenerated aluminum web having a thickness of 0.24 mm.

The regenerated aluminum web was buffed to the extent that no scratch was visually observed, and then the regenerated aluminum web was kept at room temperature for 1 hour.
Etching treatment was performed with a 0% HF aqueous solution for 45 seconds. When the surface of this recycled aluminum web was observed with a polarizing filter at a magnification of 15 times using an optical microscope, aluminum crystal grains having a width of 200 μm or less were observed on the entire surface.

1. Roughening Step The regenerated aluminum web was subjected to a roughening treatment by sequentially performing the following steps.

(1) Pre-stage etching step (2) Pre-stage desmutting step (3) DC electrolytic surface roughening step (4) Post-stage etching step (5) Post-stage desmutting step Each time each of the above steps is completed, a treatment liquid is applied with a nip roller. It was cut and washed with water. The water washing was performed by spraying water from both sides of the recycled aluminum web onto the both sides of the recycled aluminum web using a water washing nozzle in which a spray tip for drawing a fan-shaped spray pattern was provided on the tube at 100 mm intervals. The water washing nozzle was arranged so that the distance from the discharge port of the spray tip to the conveying surface of the recycled aluminum web was 100 mm. Further, after the water washing treatment, water droplets adhering to the surface of the recycled aluminum web were cut with a nip roller.

In the pre-stage etching step, pre-stage desmutting step, post-stage etching step, and post-stage desmutting step, the treatment liquid was sprayed on both sides of the recycled aluminum web. In these steps, in order to spray the treatment liquid onto the recycled aluminum web, a treatment liquid spray nozzle in which injection holes having a diameter of 4 mm were formed in the tube at intervals of 50 mm was used. The treatment liquid spray nozzle was arranged such that the distance from the injection hole to the transport surface of the recycled aluminum web was 50 mm.

Each process of the former etching process to the latter desmutting process will be described in detail below.

(1) Pre-etching step In the pre-etching step, an alkaline solution containing caustic soda and aluminum ion in an amount of 27% by weight and 6.5% by weight and having a liquid temperature of 70 ° C. was used as a treatment liquid. The treatment liquid spray nozzle was set so that the amount of dissolution of the roughened surface of the recycled aluminum web was 6 g / m ² and the amount of dissolution of the surface opposite to the roughened surface was 1 g / m ^2. The alkaline solution was sprayed and used for etching treatment.

Regarding the concentrations of caustic soda and aluminum ions in the alkaline solution, the relationship between the temperature, the specific gravity, and the conductivity of the alkaline solution and the concentrations of caustic soda and aluminum ions is obtained in advance,
The temperature, the specific gravity, and the conductivity of the alkaline aqueous solution are measured, and the concentrations of caustic soda and aluminum ions are obtained based on the measurement results. It was controlled by replenishing the solution.

(2) First Desmutting Process The waste liquid of the nitric acid solution used in the next DC electrolytic surface roughening process is liquified by the treatment liquid spray nozzle on both sides of the recycled aluminum web which has been subjected to the etching treatment in the first etching process. Desmutting was performed by spraying at a temperature of 35 ° C. for 4 seconds.

(3) DC Electrolytic Surface Roughening Step The recycled aluminum web that was desmutted in the preceding desmutting step was electrolytically surface roughened using the DC electrolytic surface roughening apparatus 100 shown in FIG.

In the DC electrolytic surface roughening apparatus 100, 12 anodes 8 and 12 cathodes were alternately arranged on the bottom surface of the electrolytic cell 2 at intervals of 100 mm along the transport direction a. Both the anode 8 and the cathode 10 had a width of 100 mm along the transport direction a. A plate-shaped electrode made of titanium was used as the anode 8, and a plate-shaped electrode made of ferrite was used as the cathode 10.

The conveying speed of the recycled aluminum web is 12
It was m / min.

The acidic electrolyte has a nitric acid concentration of 10 g /
Aluminum nitrate was added to liters of dilute nitric acid to adjust the concentration of aluminum ions to 10 g / liter, and an aqueous nitric acid solution having a liquid temperature of 50 ° C. was used.

To the anode 8 and the cathode 10, the ripple rate was 20% or less, and the same direct current as that used in ordinary plating was applied. The current densities in the anode 8 and the cathode 10 were both 50 A / dm ² , and the total amount of electricity when the recycled aluminum web was the anode was 300 C / dm ² .

The concentrations of nitric acid and aluminum ions in the nitric acid aqueous solution were controlled as follows.

A circulation tank is connected to the electrolytic cell 2, an aqueous nitric acid solution is circulated between the circulation tank and the electrolytic cell 2, and 67% by weight concentrated nitric acid and water are supplied to the circulation tank. Excessive nitric acid aqueous solution was overflowed from the circulation tank.

The relationship between the concentrations of nitric acid and aluminum ions in the nitric acid aqueous solution, the temperature of the nitric acid aqueous solution, the conductivity of the nitric acid aqueous solution, and the ultrasonic conductivity was obtained, and the temperature and conductivity of the nitric acid solution in the circulation tank were calculated. , And the ultrasonic conductivity were measured, and the amounts of concentrated nitric acid and water supplied to the circulation tank were controlled on the basis of the measured value and the amount of electricity supplied to the anode 8 and the cathode 10.

(4) Second-stage etching step The treatment liquid contains caustic soda and aluminum ion in an amount of 5% by weight and 0.5% by weight, respectively, and has a liquid temperature of 4%.
The amount of dissolution of the roughened surface in the recycled aluminum web electrolytically roughened in the direct current electrolytic roughening step using an alkaline solution of 5 ° C. was 0.2 g / m ² , and the roughened surface was Etching treatment was performed so that the amount of dissolution on the opposite surface was 0.1 g / m ² .

The concentrations of caustic soda and aluminum ions in the alkaline solution were also controlled in the same manner as in the case of the preceding etching step.

(5) Subsequent Desmut Step A sulfuric acid aqueous solution containing sulfuric acid and aluminum ions at 300 g / liter and 5 g / liter, respectively, at a liquid temperature of 70 ° C. is applied for 4 seconds on both sides of the regenerated aluminum web subjected to the etching treatment in the post-etching step. Desmutting was performed by spraying.

Regarding the concentrations of sulfuric acid and aluminum ions in the sulfuric acid aqueous solution, the relationship between the temperature, the specific gravity, and the conductivity and the sulfuric acid and aluminum ion concentrations was obtained, and the temperature, the specific gravity, and the conductivity of the sulfuric acid aqueous solution were calculated. A sulfuric acid aqueous solution having a concentration of 50% by weight and water were replenished so as to obtain a predetermined value, and the concentrations of sulfuric acid and aluminum ions were kept constant.

2. Anodizing step Sulfuric acid and aluminum ion 100 g /
The amount of the anodic oxide film was 2.4 g / m 2 in an aqueous solution of sulfuric acid having a liquid temperature of 50 ° C. and containing 5 g / l.
^A direct current was applied to the recycled aluminum web so that it was ² .

The control of the concentrations of sulfuric acid and aluminum ions in the aqueous sulfuric acid solution was carried out in the same manner as in the latter desmutting step.

3. Results When the surface of the lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750, it was found that uniform unevenness having a shape suitable for a lithographic printing plate was formed. Also, the presence of chatter marks was not recognized.

[Example 2] A defective product generated during the production of a lithographic printing original plate and a molten metal in which the recovered used lithographic printing plate was dissolved were degassed, filtered, and then cast by a usual method. An ingot was obtained. The molten metal had the following composition.

[0275]

[Table 2]

From the obtained ingot, a recycled aluminum web having a thickness of 0.24 mm was obtained according to the same procedure as in Example 1.

The regenerated aluminum web was prepared according to Example 1
When the surface of this recycled aluminum web was observed through a polarizing filter at a magnification of 15 times,
Aluminum crystal grains having a width of 200 μm or less were found on the entire surface.

1. Roughening Step The regenerated aluminum web was subjected to a roughening treatment by sequentially performing the following steps.

After each of the above steps was completed, the treatment liquid was drained off with a nip roller, washed in the same manner as in Example 1, and the reclaimed aluminum web after washing was passed through the nip roller to remove water droplets on the surface.

(1) Pre-stage etching step (2) Front stage desmut process (3) Preliminary electrolytic surface roughening process (4) Intermediate etching process (5) Intermediate desmut process (6) DC electrolytic surface roughening process (7) Post-etching process (8) Second stage desmut process.

In the former etching process, the former desmutting process, the intermediate etching process, the intermediate desmutting process, the latter etching process, and the latter desmutting process,
Using the spray nozzle described in Example 1, the treatment liquid was sprayed on both sides of the recycled aluminum web.

The above steps will be described below.

(1) Pre-Etching Step The regenerated aluminum web was subjected to etching treatment using the same alkaline solution as that used in the pre-etching step in Example 1 and following the same procedure.

(2) Previous Desmutting Treatment The regenerated aluminum web etched in the preceding etching step was desmutted by spraying the aqueous hydrochloric acid solution used in the subsequent preliminary electrolytic surface roughening step at a liquid temperature of 45 ° C. for 2 seconds.

(3) Preliminary Electrolytic Surface Roughening Process Using the AC electrolytic surface roughening device 104 shown in FIG. 3, the concentration of hydrochloric acid was 7.5 g / liter and the concentration of aluminum ions was 5 g / liter. Then, an alternating current was applied to the aluminum web in an aqueous hydrochloric acid solution having a liquid temperature of 35 ° C. prepared by adding aluminum chloride to hydrochloric acid to perform electrolytic surface roughening treatment.

As the alternating current, a trapezoidal wave current having a frequency of 60 Hz and a rising time Tp of 0.8 msec was used. The current density is, when the recycled aluminum web is an anode and when it is a cathode,
It was 50 A / m ² at the peak time. The total amount of electricity is 6 when the recycled aluminum web is an anode.
It was 0 coulomb / dm ² , and Qc / Qa in one cycle of the alternating current was 0.95.

Regarding the concentrations of hydrochloric acid and aluminum ions in the aqueous hydrochloric acid solution, the relationship between the temperature, the conductivity, and the ultrasonic wave propagation velocity and the concentrations of hydrochloric acid and aluminum ions was obtained, and the temperature, the electrical conductivity, and the superconductivity of the aqueous hydrochloric acid solution were determined. Concentrated hydrochloric acid having a concentration of 35% by weight and water are supplied to a circulation tank connected to an AC electrolytic cell in the AC electrolytic surface-roughening device 104 so that the sound wave propagation velocity becomes a predetermined value, and excess hydrochloric acid aqueous solution overflows. Then, the liquid was discharged outside the circulation tank and kept constant.

(4) Intermediate Etching Step As the treating liquid, caustic soda and aluminum ion are contained at 27% by weight and 7% by weight, respectively, and the liquid temperature is 40%.
℃ alkaline solution sprayed by the spray nozzle, the preliminary electrolytic dissolution of roughened surface in the electrolytic graining treatment reproduction aluminum web roughening process 0.3 g / m ²
The amount of dissolution of the surface opposite to the roughened surface is 0.2
Etching treatment was performed so as to obtain g / m ² .

The concentrations of caustic soda and aluminum ions in the alkaline solution were also controlled in the same manner as in the case of the preceding etching step in Claim Steel 1.

(5) Intermediate Desmut Treatment The waste solution of the nitric acid solution used in the next DC electrolytic surface roughening step is liquified by the treatment liquid spray nozzle on both sides of the recycled aluminum web which has been subjected to the etching treatment in the intermediate etching step. Desmutting was performed by spraying at a temperature of 50 ° C. for 4 seconds.

(6) DC Electrolytic Surface Roughening Step The recycled aluminum web desmutted in the intermediate desmutting step was subjected to the same DC electrolytic surface roughening apparatus as that used in the DC electrolytic surface roughening step in Example 1. The electrolytic graining treatment was performed in the same procedure.

(7) Subsequent Etching Step The regenerated aluminum web electrolytically surface-roughened in the DC electrolytic surface-roughening step was etched according to the same procedure as in the post-step etching step in Example 1.

(8) Post Desmut Process In the post desmut process, the desmut process was performed according to the same procedure as in the post desmut process of Example 1.

2. Anodizing Step The recycled aluminum web roughened in the roughening step was anodized according to the same procedure as the anodizing step in Example 1.

3. Results When the surface of the lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750, it was found that uniform unevenness having a shape suitable for a lithographic printing plate was formed. Also, the presence of chatter marks was not recognized.

[Example 3] 1. Production of lithographic printing plate support In the roughening step, the roughening treatment was performed in the same manner as in Examples 1 and 2 except that the mechanical roughening step was performed prior to the preceding etching step, and the anodizing treatment was performed. Anodizing treatment was performed in the process.

In the mechanical surface roughening step, the mechanical surface roughening treatment was performed as follows.

As the abrasive slurry, a suspension obtained by suspending silica sand having a specific gravity of 1.12 in water was used. The suspension was provided along the transport direction of the aluminum web above the transport surface which is the transport path of the aluminum web. Mechanical roughening treatment was performed by a mechanical roughening device having three roller-shaped brushes.

As the roller-shaped brush, a No. 3 nylon brush having a bristle length of 50 mm, which was densely planted on the surface of a stainless steel roller having a diameter of 300 mm, was used.

In the mechanical surface roughening device, two stainless steel supporting rollers each having a diameter of 200 mm are arranged on the opposite side of the roller brush across the conveying surface, for each roller brush. I set it up. The support rollers were arranged so that the distance between the centers was 300 mm.

The roller-like brush has an average surface roughness of the aluminum web of 0.3 to 0.35 after the mechanical roughening treatment.
The aluminum web was pressed against the aluminum web with a pressure of μm, and was rotated so that the rotation direction on the roughened surface was the same as the transport direction of the aluminum web. The pressure for pressing the roller brush against the aluminum web was controlled based on the load of the drive motor that rotates the roller brush.

Incidentally, the concentration of silica sand in the abrasive slurry is continuously determined from the temperature and the specific gravity of the abrasive slurry, and water and silica sand are replenished so that the concentration becomes constant, and mechanical coarseness is increased. Surface treatment was performed. Further, the silica sand pulverized and finely granulated in the mechanical surface roughening treatment was continuously removed by a cyclone so that the particle size distribution of the silica sand in the abrasive slurry was made substantially constant. The particle size of the silica sand during the mechanical surface roughening treatment was in the range of 1 to 15 μm, and the average particle size was 8 μm when measured with a laser particle size distribution meter (LA910 type manufactured by Horiba, Ltd.). .

2. When the surface of the resulting lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750, it was found that uniform unevenness having a shape suitable for a lithographic printing plate was formed. Also, the presence of chatter marks was not recognized.

[Embodiment 4] In Embodiments 1 and 2,
In the subsequent desmutting step, the recycled aluminum web is desmutted using the drainage of the sulfuric acid solution discharged from the subsequent anodizing step, and the anodizing step is performed without washing the recycled aluminum web after desmutting with water. A lithographic printing plate support was prepared in the same manner as in Examples 1 and 2 except that the anodic oxidation treatment was carried out in.

The surface of the obtained lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750 times, and it was found that uniform unevenness having a shape suitable for a lithographic printing plate was formed. Also, the presence of chatter marks was not recognized.

[Example 5] Example 5 was the same as Example 3 except that the post-etching step was performed so that the dissolved amount of the roughened surface of the recycled aluminum web would be 1.2 g / m ^2. It carried out similarly.

The surface of the obtained lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750 times, and it was found that uniform unevenness having a shape suitable for a lithographic printing plate was formed. Also, the presence of chatter marks was not recognized.

[Embodiment 6] In Embodiments 1 and 2,
In the direct current electrolytic surface roughening step, the direct current electrolytic surface roughening device shown in FIG. 2 is used in place of the direct current electrolytic surface roughening device shown in FIG. 1, and the electrolytic surface roughening treatment is performed with the distance between the anode and the cathode being 800 mm. The same procedure as in Examples 1 and 2 was carried out except for the above.

The surface of the obtained lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750 times, and it was found that uniform unevenness having a shape suitable for a lithographic printing plate was formed. Also, the presence of chatter marks was not recognized.

[Example 7] The method described in Example 1 of JP-A-60-149491 having the following composition on the roughened surface of the lithographic printing plate supports prepared in Examples 1-6. The undercoat liquid was applied and dried at 80 ° C. for 30 seconds to form an undercoat layer. The amount of the undercoat layer after drying was 10 mg / m ² .

[Undercoat Liquid Composition] Dihydroxyethylglycine: 0.05 parts by weight Methanol: 94.95 parts by weight Water: 5.00 parts by weight In the Example 1 of the above publication having the following composition on the undercoat layer. The photosensitive resin solution described above was applied and dried at 100 ° C. for 2 minutes to form a positive type visible light exposure type plate-making layer to prepare a positive type lithographic printing original plate. The coating amount of the visible light exposure type plate-making layer after drying was 2.5 g / m ² .

[Composition of Photosensitive Resin Solution] a. Ester compound of naphthoquinone-1,2-diazide-5-sulfonyl chloride and pyrogallol-acetone resin ... 0.73 g b. Cresol novolac resin ... 2.00 g c. Oil blue # 603 (manufactured by Orient Chemical Co., Ltd.) ... 0.04 g d. Ethylene dichloride ... 16 g e. 2-Methoxyethylacetate ... 12 g The obtained lithographic printing plate precursor was exposed and developed, and a printing test was conducted. As a result, it was found that good printing characteristics were exhibited.

Example 8 The lithographic printing plate supports prepared in Examples 1 to 6 were treated with a liquid temperature of 70 ° C. and a concentration of 2.5 as described in JP-A-59-101651. It was made hydrophilic by immersing it in a 3 wt% sodium silicate solution for 10 seconds.

On the roughened surface of the hydrophilized lithographic printing plate support, as described in Example 1 of the above-mentioned Japanese Patent Laid-Open Publication, mainly methyl methacrylate / ethyl acrylate /
Sodium 2-acrylamido-2-methylpropane sulfonate copolymer (molar ratio of monomer units ... 50: 3
0:20, an average molecular weight of about 60,000) and a coating amount of 0.05 g / m ² was formed. The undercoat layer was dried at 100 ° C. for 30 seconds.

On the undercoat layer, a photosensitive resin solution having the following composition was applied and dried at 120 ° C. for 60 seconds to form a negative type visible light exposure type plate making layer, and a negative type lithographic printing original plate was prepared. Was produced.

[Composition of Photosensitive Resin Solution] a. 2-Hydroxyethyl methacrylate copolymer 0.87 g (described in Example 1 of US Pat. No. 4,123,276) b. 2-Methoxy-4-hydroxy-5-benzoylbenzenesulfonate of a condensate of p-diazodiphenylamine and paraformaldehyde ... 0.1 g c. Oil blue # 603 (manufactured by Orient Chemical Industry Co., Ltd.) ... 0.03 g d. Methanol ... 6 g e. 2-Methoxyethanol ... 4 g The coating amount after drying was 2.0 g / m ² .

The lithographic printing plate precursor thus obtained was exposed and developed, and a printing test was carried out. As a result, it was found that good printing characteristics were exhibited.

Example 9 The lithographic printing plate supports obtained in Examples 1 to 6 were treated at a liquid temperature of 30 ° C. and a concentration of 1% by weight, as described in JP-A-2000-62333. Three
It was made hydrophilic by immersing it in a sodium silicate solution for 10 seconds.

The undercoat liquid having the following composition was applied to the roughened surface of the hydrophilized support for a lithographic printing plate as described in Example 1 of the above-mentioned Japanese Patent Laid-Open Publication, and the temperature was 100 ° C. for 10 seconds. An undercoat layer having a coating amount of 10 mg / m ² was formed by drying.

[Undercoat Liquid Composition] a. β-alanine ... 0.5 g b. Methanol ... 95 g c. Water ... 5 g Then, a positive type laser plate making layer forming liquid solution having the following composition was applied onto the undercoat layer using a wire bar so that the coating amount after drying was 1.8 g / m ^2.
It was dried at 0 ° C. for 2 minutes to form a positive type laser plate making layer.

[Positive Laser Plate Making Layer Forming Liquid Solution Composition] a. Alkali-soluble polymer A ... 0.7 g b. 2,6-Dimethylene- (4,5-naphthalene-1,2,3-trimethylpyrrole) -4-monochloro-5.6-propane-heptene-methylbenzenesulfonate [cyanine dye (alkali dissolution inhibitor)] .1 g c. Tetrahydrophthalic anhydride ... 0.05 g d. A dye in which the counter anion of Victoria Pure Blue BOH is changed to a 1-naphthalenesulfonic acid anion ... 0.02 g e. Fluorine-based surfactant (Megafuck F-177, manufactured by Dainippon Ink and Chemicals, Inc.) ... 0.05 g f. γ-butyrolactone ... 8 g g. Methyl ethyl ketone ... 8 g h. 1-Methoxy-2-propanol ... 4 g The alkali-soluble polymer A was synthesized according to the following procedure.

In a 500 ml three-necked flask equipped with a stirrer, a condenser and a dropping funnel, 31.0 g of methacrylic acid was added.
(0.36 mol), 39.1 g of ethyl chloroformate (0.
26 mol) and 200 ml of acetonitrile were charged, the mixture was stirred while cooling in an ice-water bath, and 36.4 g (0.36 mol) of triethyleneamine was added using the dropping funnel over about 1 hour.

After adding triethyleneamine, the mixture is allowed to stand at room temperature for 30 minutes.
Stir for 5 minutes and p-aminobenzenesulfonamide 51.
7 g (0.30 mol) was added, and the mixture was stirred for 1 hour while heating to 70 ° C. in an oil bath.

After stirring for 1 hour, the contents of the closed-necked flask were emptied into water to form a slurry, and the solid substance was collected by filtration to give N-
A white solid of (p-aminosulphenyl) methacrylamide was obtained.

5.04 g (0.021 mol) of N- (p-aminosulphenyl) methacrylamide, 2.05 g (0.018 mol) of ethyl methacrylate, 1.11 g (0.021 mol) of acrylonitrile and N , N-dimethylacetamide (20 g) were added and heated to 65 ° C.,
0.15 g of V-65 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged and stirred for 2 hours under a nitrogen stream.

The resulting reaction product was further added with the N- (p-
Aminosulfenyl) methacrylamide 5.04 g
(0.021 mol) and ethyl methacrylate 2.05 g
(0.018 mol) and acrylonitrile 1.11 g
(0.021 mol) and N, N-dimethylacetamide 2
A mixture of 0 g and V-65 (manufactured by Wako Pure Chemical Industries, Ltd.) 0.15 g was added dropwise over 2 hours to carry out a polymerization reaction.

After completion of the reaction, 40 g of methanol was added to the obtained reaction solution, mixed for 30 minutes, the precipitate was collected by filtration and dried to obtain 15 g of white alkali-soluble polymer A.
The alkali-soluble polymer A has a molecular weight of 53,000.
Met.

Output of the obtained lithographic printing original plate was 500 m.
A printed image is directly written at a main scanning speed of 5 m / sec using a semiconductor laser device having W, a wavelength of 830 nm, and a beam diameter of 17 μm, developed with an alkaline developer 1 or alkaline developer 2 having the following composition for 30 seconds, and lithographically processed. A printing plate was prepared.

[Composition of Alkaline Developer 1] a. Caustic soda 2.8% by weight b. Silica ... 2.0% by weight c. Nonionic surfactant (Pluronic PE-3100, manufactured by BASF) 0.5% by weight d. Water: 94.7% by weight [Composition of alkaline developer 2] a. Caustic potash ... 2.8% by weight b. D-sorbit ... 2.5% by weight c. Diethylenetriamine penta (methylene sulfonic acid) 5Na salt ... 0.1% by weight d. Nonionic surfactant (Pluronic P-85, manufactured by Asahi Denka Kogyo Co., Ltd.) 0.5 wt% e. Water: 94.5% by weight When printing was carried out using the lithographic printing plate, it was found to have good printing performance.

Example 10 The lithographic printing plate supports obtained in Examples 1 to 6 were coated with an undercoating liquid having the following composition as described in Example 2 of JP-A-2000-62333. Then, it was coated so that the coating amount after drying was 11 mg / m ² and dried at 100 ° C. for 20 seconds to form an undercoat layer.

[Undercoat Liquid Composition] a. β-alanine ... 0.1 g b. Phenylsulfonic acid ... 0.05 g c. Methanol ... 40 g d. Water: 60 g Then, a negative type laser plate making layer forming liquid solution having the following composition was applied on the undercoat layer using a wire bar so that the coating amount after drying was 1.5 g / m ² and dried. Then, a negative type laser plate making layer was formed.

[0332]     [Composition of Negative Laser Plate Making Layer Forming Liquid Solution]   a. Nonylphenol (acid crosslinkable compound) ... 0.05 g   b. 2,4,6-Trimethoxydiazonium-2,6, -dimethylbenzene Ruphonate (acid precursor) 0.3 g   c. Crosslinking agent A (acid crosslinkable compound) ... 0.5 g   d. Poly (p-hydroxystyrene) (alkali-soluble resin)                                                     … 1.5g   e. 2,6-dimethylene- (4,5-naphthalene-1,2,3-trimethylpyrene Roll) -4-monochloro-5.6-propane-heptene-methylbenzenesul Honate (cyanine dye, infrared absorber) ... 0.07g   f. Aizen spirone blue C-RH (Hodogaya Chemical Co., Ltd.)                                                     ... 0.035g   g. Megafac F-177 (manufactured by Dainippon Ink and Chemicals, Inc., fluorine-based interfacial active Sexual agent) ... 0.01 g   h. Methyl ethyl ketone ... 12g   i. Methyl alcohol ... 10g   j. 1-methoxy-2-propanol ... 8 g The cross-linking agent A was synthesized by the following procedure.

1- [α-Methyl-α- (4-hydroxyphenyl) ethyl] -4- [α, α-bis (4-hydroxyphenyl) ethyl] benzene was reacted with formalin in an aqueous potassium hydroxide solution.

The obtained reaction solution was acidified with sulfuric acid and crystallized to obtain a crosslinking agent A having a purity of 92%.

The lithographic printing plate precursor on which the negative type laser plate making layer is formed is exposed by using a semiconductor laser device to obtain a developing solution P.
D-4 (manufactured by Fuji Photo Film Co., Ltd., 1: 8 water diluted solution)
And then developed.

When printing was carried out using the lithographic printing plate, it was found that it had good printing performance.

[Embodiment 11] Japanese Patent Laid-Open No. 2000-62333.
As described in Example 3 of the publication, methyleneeth
Xysilane 50 g, acetic acid 1.1 g, distilled water 7.7 g,
And 100 g of ethanol are mixed at room temperature, then at 80 ° C.
The mixture was heated to prepare a sol. The obtained sol was used in Example 1
The coating amount after drying on the lithographic printing plate support obtained in
20 mg / m ²And apply at 170 ℃ for 10 minutes
And dried to form an undercoat layer.

Next, a photopolymerizable laser plate-making layer forming liquid having the following composition was applied so that the coating amount after drying would be 1.5 g / m ² , and dried to form a photopolymerizable laser plate-making layer. did.

[Composition of Photopolymerizable Laser Plate-Making Layer Forming Liquid] a. Pentaerythritol tetraacrylate (vinyl polymerizable compound) ... 1.5 g b. Allyl methacrylate / methacrylic acid copolymer (copolymerization ratio 80/20) ... 2.0 g c. 1,2- (p-styrylphenyl) -4,6-bis (trichloromethyl) -S-triazine (sensitizer) 0.2 g d. Propylene glycol monomethyl ester ... 20 g e. Methyl ethyl ketone ... 20 g f. Megafac F-177 (manufactured by Dainippon Ink and Chemicals, Inc., fluorine-based surfactant) ... 0.03 g g. Oil-soluble dye (Victoria Pure Blue BOH) ... 0.02 g The lithographic printing original plate on which the photopolymerizable laser plate-making layer is formed,
It was exposed to light using a YAG laser with a filtering amount of 0.0132 mW / cm ² , and immersed in the alkaline developer 1 of Example 9 for development.

When printing was carried out using the above lithographic printing plate, it was found that it had good printing performance.

[Embodiment 12] In Embodiments 1 to 6, instead of washing with water after the completion of each step, the particle diameter is 5 to 500 μm.
A lithographic printing plate support was prepared according to the same procedure, except that the dry ice powder in 1 above was sprayed and washed.

Since the amount of waste liquid discharged in the cleaning process is greatly reduced, the cost required for waste liquid treatment is also significantly reduced.

[Comparative Example 1] In Example 1, after the pre-stage etching process and the pre-stage desmutting process were completed, instead of electrolytic surface roughening with DC, an AC electrolytic surface roughening device shown in FIG. It was applied and electrolytically roughened.

The acidic electrolyte has a nitric acid concentration of 10.5.
Aluminum nitrate was added to dilute nitric acid of g / liter to adjust the concentration of aluminum ions to 4 g / liter, and an aqueous nitric acid solution having a liquid temperature of 50 ° C. was used.

As the alternating current, commercial alternating current having a frequency of 60 Hz is used as an electric current by using an induction voltage regulator and a transformer.
The sine wave generated by adjusting the voltage was used.
The current density was 50 A / m ² at the time of the peak of the alternating current in both cases where the recycled aluminum web was an anode or a cathode.
Met. The total amount of electricity when the recycled aluminum web was an anode was 300 C / dm ² , and Qc / Qa in one cycle of the alternating current was 0.95.

When the surface of the obtained lithographic printing plate support was observed with a scanning electron microscope at a magnification of 750, the shape of the surface irregularities was negative and uniform as compared with Example 1.

[0347]

As described above, according to the present invention,
Provided is a method for producing a lithographic printing plate support in which chatter marks are not generated even when a roughening treatment is performed at high speed when producing a lithographic printing plate support from a recycled aluminum plate. According to the present invention, further, the lithographic printing plate support produced by the above-mentioned production method, and the lithographic printing plate support as a support, which is excellent in printing durability by exposure and development, and stains Also, a lithographic printing original plate capable of producing a lithographic printing plate without stains on the blank can be obtained.

[Brief description of drawings]

FIG. 1 is an example of a direct current electrolytic surface roughening device used in a direct current electrolytic surface roughening step in a method for producing a lithographic printing plate support of the present invention.

FIG. 2 is another example of the DC electrolytic surface roughening device used in the DC electrolytic surface roughening step in the method for manufacturing a lithographic printing plate support of the present invention.

FIG. 3 is an example of an AC electrolytic surface roughening device used in a preliminary electrolytic surface roughening step in the method for producing a lithographic printing plate support of the present invention.

[Explanation of symbols]

2 electrolysis tank 4 Conveyor rollers 6 Conveyor rollers 8 anode 10 cathode 12 Acidic electrolyte supply line 16 Acidic electrolyte discharge line 20 electrolyzer 22A Anode chamber 22B cathode chamber 24 transport rollers 30 anode 32 cathode 34 Liquid supply pipe 36 Drainage pipe 40 AC electrolyzer 42 AC electrolytic cell body 44 feed roller 46A Main pole 46B Main pole 48A liquid supply nozzle 48B liquid supply nozzle 100 DC electrolytic surface roughening device 102 DC electrolytic surface roughening device 104 AC electrolytic surface roughening device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C23F 1/36 C23F 1/36 C25D 11/04 C25D 11/04 E 11/16 301 11/16 301 11 / 18 11/18 A 301 301A 313 313 C25F 3/04 C25F 3/04 A B 7/00 7/00 L (72) Inventor Hirokazu Sawada 4000 Kawasakiri, Yoshida-cho, Hara-gun, Shizuoka Fuji-Sha Shin Film Co., Ltd. 72) Inventor Akio Uesugi 4000 Kawajiri, Yoshida-cho, Hara-gun, Shizuoka Prefecture F-term in Fuji Shashin Film Co., Ltd. CA17 CA53 4K057 WA01 WA05 WA19 WB05 WB11 WD05 WE21 WE22 WG07 WG10 WK01 WN10

Claims (21)

[Claims] 1. A roughening step of roughening at least one surface of a recycled aluminum plate manufactured from recycled aluminum ingot, wherein the roughening step is performed by acidifying the recycled aluminum plate with an acid. In the electrolytic solution, having a direct current electrolytic surface roughening step of electrolytic surface roughening treatment by direct current, in the direct current electrolytic surface roughening step, while being arranged alternately with each other, in the acidic electrolytic solution While applying direct current to the immersed anode and cathode, the regenerated aluminum plate, the acidic electrolysis so as to be separated from the anode and the cathode by a distance at which electrolytic roughening occurs by the anode and the cathode A method for producing a support for a lithographic printing plate, which comprises passing through a liquid for electrolytic graining treatment. 2. In the DC electrolytic surface roughening step,
Anodes and cathodes, which are alternately arranged along a transport surface that is a transport path of the recycled aluminum plate, are immersed in the acidic electrolyte during the roughening treatment, and a direct current is applied, and the anode and The electrolytic surface-roughening treatment is performed by using a DC electrolytic surface-roughening device that contains at least one of the cathodes and one or more electrolytic cells that contain the acidic electrolyte. The method for producing the support for a lithographic printing plate as described in. 3. A preliminary electrolytic roughening process in which the roughening step is performed by electrolytically roughening the regenerated aluminum plate in a hydrochloric acid aqueous solution containing hydrochloric acid as a main acid component prior to the direct current electrolytic roughening step. The method for producing a lithographic printing plate support according to claim 1 or 2, which comprises a surface-imparting step. 4. The surface roughening step comprises: (a) prior to the direct current electrolytic surface roughening step;
A pre-stage etching step of etching by contacting with an alkaline solution, and (b) a recycled aluminum plate electrolytically surface-roughened in the direct current electrolytic surface-roughening step, a post-stage etching of etching by contacting with an alkali solution. The method for producing a lithographic printing plate support according to any one of claims 1 to 3, further comprising: 5. An intermediate etching step of etching the regenerated aluminum plate electrolytically surface-roughened in the preliminary electrolytic surface-roughening step by contacting it with an alkaline solution, the direct-current electrolytic surface-roughening In the process,
The method for producing a lithographic printing plate support according to claim 3 or 4, wherein the recycled aluminum plate etched in the middle etching step is subjected to electrolytic surface roughening treatment. 6. The surface roughening treatment step comprises a mechanical surface roughening step of subjecting at least one surface of the regenerated aluminum plate to a mechanical surface roughening treatment prior to the pre-stage etching step. 4. The method for producing a lithographic printing plate support as described in 4 or 5. 7. In the pre-stage etching step,
The method for producing a lithographic printing plate support according to any one of claims 4 to 6, wherein an etching treatment is performed so that a dissolved amount of the recycled aluminum plate becomes ¹ to 15 g / m ² . 8. In the latter etching step,
Dissolved amount of the recycled aluminum plate is 0.01 to 5 g / m
^The method for producing a lithographic printing plate support according to any one of claims 4 to 7, wherein the etching treatment is performed so as to obtain ² . 9. The roughening step comprises a pre-desmut step of contacting the regenerated aluminum plate with an acidic solution to desmut after the pre-etching step. A method for producing a support for a lithographic printing plate according to the item. 10. The roughening step comprises a post-desmutting step of desmutting the regenerated aluminum plate by contacting it with an acidic solution subsequent to the post-etching step. A method for producing a support for a lithographic printing plate according to the item. 11. The surface roughening step comprises an intermediate stage desmutting step in which the recycled aluminum plate is brought into contact with an acidic solution and desmutted subsequent to the intermediate etching step. A method for producing a support for a lithographic printing plate according to the item. 12. In the roughening step, the direct current electrolytic surface roughening step is performed subsequent to the pre-stage desmutting step, and in the pre-stage desmutting step,
The method for producing a lithographic printing plate support according to claim 1, wherein the acidic electrolytic solution used in the DC electrolytic surface roughening step is used as an acidic solution. 13. In the roughening step, the preliminary electrolytic surface roughening step is performed subsequent to the pre-stage desmutting step, and in the pre-stage desmutting step,
The hydrochloric acid solution used in the preliminary electrolytic surface roughening step is used as the acidic solution, and in the intermediate desmutting step, the acidic electrolytic solution used in the direct current electrolytic surface roughening step is used as the acidic solution. 10-12
A method for producing the lithographic printing plate support according to any one of 1. 14. The recycled aluminum plate has an aluminum content of 95 to 99.4% by weight.
14. The method for producing a lithographic printing plate support according to any one of 13 above. 15. The roughened surface of the recycled aluminum plate, which has been roughened in the roughening step, is anodized in an acidic electrolyte. The method for producing a lithographic printing plate support according to claim 1, further comprising an anodic oxidation step of forming an anodic oxide film on the surface. 16. The production of a lithographic printing plate support according to claim 15, wherein in the anodizing step, a hydrophilizing treatment for hydrophilizing the anodized film formed on the roughened surface of the recycled aluminum is performed. Method. 17. The planographic printing plate according to claim 15 or 16, wherein in the anodizing step, a sealing treatment is performed to seal small holes in the anodized film formed on the roughened surface of the recycled aluminum. A method for manufacturing a support. 18. In the subsequent desmutting step,
The method for producing a lithographic printing plate support according to claim 15, wherein the acidic electrolytic solution used in the anodizing treatment is used as an acidic solution. 19. After the completion of at least one of the roughening step and the anodizing step, dry ice particles are sprayed onto the roughened surface of the recycled aluminum plate to clean the roughened surface. Item 19. A method for producing a support for a lithographic printing plate according to any one of Items 1 to 18. 20. A lithographic printing plate support produced by the production method according to claim 1. 21. A lithographic printing original plate obtained by forming a plate making layer on the roughened surface of the lithographic printing plate support according to claim 20.