JP2003328094A - Production method for rolled aluminum alloy plate for lithographic printing form plate support - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a rolled aluminum alloy plate for a lithographic printing form plate support used after an electrochemical surface roughening treatment, whereby the rolled aluminum alloy plate excellent in electrolytic graining properties and free of the occurrence of streaks is obtained. <P>SOLUTION: After an alloy ingot comprising 0.0001-0.03% Cu, 0.005-0.03% Ti, 0.1-0.5% Fe, 0.05-0.20% Si, and the balance substantially Al is subjected to a homogenizing treatment at 500-620°C for at least 1 hr, hot rolling is carried out by conducting rough rolling and finish rolling. The rough rolling is started at 380-450°C. In the finish rolling, the temperature difference between the center part and the end part in the plate width direction is set at 20°C or less. The finish rolling completion temperature is set at 280-350°C. Thus rolled alloy is wound up into a coil, whereby causing the recrystallization to occur after the completion of hot rolling, and then is given a specified thickness by cold rolling, thus giving the rolled aluminum alloy plate for the lithographic printing form plate support in which the average particle size of crystal particles in the plate surface in the direction perpendicular to the rolling direction is 60 μm or less. The alloy contains at least one element selected from In, Sn, Pb, Ni, and Be and/or at least one element selected among Mn, Cr, and Zr. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an aluminum alloy rolled plate used as a support for a lithographic printing plate, and more specifically, it is used after being subjected to electrochemical graining treatment (electrolytic graining). A method for producing an aluminum alloy plate for a lithographic printing plate support, which has excellent electrolytic graining properties and does not cause streaks during electrochemical graining treatment, as an aluminum alloy rolled plate for a lithographic printing plate support. is there.

[0002]

2. Description of the Related Art Photosensitive lithographic printing plates having an aluminum alloy plate as a support have been widely used for offset printing. A lithographic printing plate precursor is generally produced by roughening the surface of an aluminum alloy plate as a support, further applying an anodizing treatment, applying a photosensitive solution and drying the solution to form a photosensitive layer. When using such a lithographic printing plate precursor, after being exposed to an image, it is developed with a developing solution, the exposed portion is removed in the positive type lithographic printing plate precursor, and it is not in the negative type lithographic printing plate precursor. The exposed portion is removed and the plate is made into a lithographic printing plate. After that, the planographic printing plate is coated with ink on its surface and is used for printing.
As described above, in the lithographic printing plate precursor, the physical properties of the photosensitive layer are changed by exposure, and the plate making is performed by utilizing the change in the physical properties.

By the way, as a roughening treatment method of an aluminum alloy plate as a support for a lithographic printing plate, a mechanical roughening treatment method such as a ball grain or a brush grain has been conventionally used, and an electrolysis mainly containing hydrochloric acid, nitric acid or the like. Electrochemical surface roughening treatment method (electrolytic graining) of electrolytic etching using liquid, chemical surface roughening method of etching with acid solution or alkaline solution, etc. are known. Since the rough surface obtained by the roughening treatment method has excellent printing performance, it has recently been roughened by the electrochemical roughening treatment method or the electrochemical roughening treatment method and other roughening treatments. Roughening is the mainstream in combination with treatment methods.

As a support for a lithographic printing plate, an aluminum alloy plate which is generally lightweight and excellent in surface treatment and workability is usually used. Conventionally, an aluminum alloy plate for such a purpose is used. Is JIS A1050,
An aluminum alloy rolled plate made of JIS A1100, JIS A3003 or the like having a plate thickness of about 0.1 to 0.5 mm is used, and such an aluminum alloy rolled plate is
The surface of the printing plate is roughened and, if necessary, anodized, and then used in a printing plate. Specifically, JP-A-48
No. 49501, an aluminum lithographic printing plate sequentially subjected to mechanical surface roughening treatment, chemical etching treatment, and anodized film treatment, or JP-A-51-1462.
The aluminum lithographic printing plate which was subjected to the electrochemical treatment, the post-treatment and the anodizing treatment described in No. 34 in that order, and the chemical etching treatment and the anodizing treatment described in JP-B-48-28123. Aluminum planographic printing plate or after mechanical roughening treatment
Aluminum lithographic printing plates which have been subjected to the treatment described in No. 123 are known.

In addition, as a method for producing an aluminum alloy rolled plate for a lithographic printing plate support as described above, generally, hot rolling is performed, and then the hot rolled plate is subjected to primary cold rolling to a predetermined temperature. It is general that the intermediate plate thickness is set to the intermediate plate thickness, the intermediate annealing is performed at that stage, and finally the secondary cold rolling is performed to finish the product plate thickness.

[0006]

The aluminum alloy plate for a lithographic printing plate support which is used after being subjected to an electrochemical surface roughening treatment and a method for producing the same are described below in (1) to (4).
Performance is required. (1) Adhesion to a photosensitive layer as a lithographic printing plate support,
In order to improve the water retention of the aluminum plate and the aluminum plate, pits (unevenness) having an appropriate depth and diameter and their size are made uniform by electrochemical graining treatment on the entire surface of the support. An aluminum alloy plate that can be formed on. Such performance is generally referred to as electrolytic graining property. (2) When electrochemically roughening the aluminum alloy plate for a support, from the viewpoint of energy saving, it is possible to form uniform and fine pits with the least amount of electricity. (3) The plate may be subjected to a heat treatment (burning treatment) in the temperature range of 200 to 300 ° C. for 3 to 7 minutes after the image portion is formed in order to increase printing durability. If the support is softened and its strength is lowered, the handling property of the subsequent processing step is deteriorated and the plate is bent, which causes inconvenience, and further it becomes impossible to set the plate on the printing machine. In addition, inconvenience occurs such that the color of the plate cannot be found in multicolor printing. Therefore, an aluminum alloy plate for a lithographic printing plate support is required to have excellent heat softening resistance so that the softening due to the burning treatment does not significantly reduce the strength. This heat softening resistance is generally called burning resistance. (4) The number of steps in manufacturing the aluminum alloy plate for a support can be reduced to achieve cost saving.

Among these (1) to (4), recently, there is a strong demand for cost saving, and therefore, the number of manufacturing steps of the aluminum alloy rolled plate for a lithographic printing plate support is reduced, that is, the manufacturing. There is a strong desire to simplify the process.

In addition to the above-mentioned demand for cost reduction, the demand for energy saving in the material manufacturing process is becoming more important not only because of the demand for global environment conservation. Therefore, the present inventors are studying a method of simplifying the manufacturing process of an aluminum alloy rolled plate for a lithographic printing plate support by reducing the number of steps.

Here, as one of the methods for simplifying the manufacturing process of the aluminum alloy rolled sheet, it is conceivable to omit intermediate annealing in the middle of cold rolling after hot rolling. However, in the manufacturing process of the aluminum alloy rolled plate for lithographic printing plate support, the intermediate annealing during the cold rolling,
It is necessary not only to soften the material but also to recrystallize the material finely and uniformly to make the final plate structure fine and uniform, thereby ensuring the electrolytic graining property as a lithographic printing plate support. It is supposed to be a process. Therefore, in order to omit the intermediate annealing during the cold rolling in the conventional manufacturing process, self-recrystallization (self-recrystallization) by the heat during hot rolling is performed during the hot rolling and at the stage of coil winding immediately after the hot rolling. Annealing) can be considered.

However, in the case of self-recrystallizing in the stage of such hot rolling-winding, the recrystallized grain size becomes larger than that in the case of recrystallization by the intermediate annealing during the cold rolling. It is common to show trends. If the recrystallized grains in the state of the hot rolled plate are large in this way, the effect remains until the final rolled plate, and the crystal structure of the product plate becomes coarse or non-uniform, resulting in electrochemical Appearance unevenness (streaks) occurs in the form of strips or streaks on the surface after the roughening treatment, and the surface appearance quality of the printing plate deteriorates. In addition, due to nonuniform temperature of the plate during hot rolling, it may not be partially recrystallized or the degree of recrystallization may be nonuniform. After the treatment, streaks occur and the surface appearance quality is impaired.

The present invention has been made in view of the above circumstances. Mainly from the viewpoints of cost reduction and energy saving, intermediate annealing in the middle of cold rolling is omitted, and recrystallization is performed in the stages of hot rolling to winding. Of the aluminum alloy rolled plate for a lithographic printing plate support, which has a low risk of streak generation (that is, a good streak property) and an excellent electrolytic graining property after the electrochemical roughening treatment. It is intended to provide a manufacturing method.

[0012]

[Means for Solving the Problems] As a result of various experiments and examinations conducted by the present inventors to solve the above problems, it is necessary to appropriately regulate the conditions of the hot rolling process, particularly the temperature conditions of finish rolling. Thus, the inventors have found that an aluminum alloy rolled plate for a lithographic printing plate support having excellent streak properties can be obtained, and have completed the present invention.

Specifically, the method for producing an aluminum alloy rolled plate for a lithographic printing plate support according to the first aspect of the present invention is based on Cu
0.0001 to 0.03%, Ti 0.005 to 0.03
%, Fe 0.1 to 0.5%, Si 0.05 to 0.20%
Is cast, and an aluminum alloy containing Al and unavoidable impurities in the balance is cast, and the cast ingot is cast at 500 to 620 ° C.
After performing homogenizing treatment at a temperature within the range of 1 hour or more, when hot rolling is performed by rough rolling and finish rolling, the hot rough rolling start temperature is set within the range of 380 to 450 ° C., and hot finishing is performed. During the rolling, the temperature difference between the central portion in the plate width direction and the end portion in the plate width direction is set to 20 ° C. or less, and the hot finish rolling end temperature is set in the range of 280 to 350 ° C. Recrystallization after rising, and then cold rolling to a final plate thickness, whereby an aluminum alloy rolling for lithographic printing plate support having an average particle size of 60 μm or less in the direction perpendicular to the rolling direction of the crystal grains on the plate surface It is characterized by obtaining a plate.

The method for producing an aluminum alloy rolled plate for a lithographic printing plate support according to the second aspect of the present invention is Cu 0.000.
1 to 0.03%, Ti 0.005 to 0.03%, Fe
0.1 to 0.5%, Si 0.05 to 0.20%, In 0.001 to 0.05%, Sn 0.00
1-0.05%, Pb 0.001-0.05%, Ni
0.001-0.05%, and Be0.0001-
An aluminum alloy containing one or more of 0.01% and the balance of Al and unavoidable impurities is cast, and the ingot is homogenized for 1 hour or more at a temperature in the range of 500 to 620 ° C. When hot rolling is performed by rough rolling and finish rolling after the treatment, the hot rough rolling start temperature is set in the range of 380 to 450 ° C., and the center portion and the plate width in the plate width direction during hot finish rolling are set. The temperature difference from the end of the direction is 20 ° C. or less, and the finish temperature of hot finish rolling is set in the range of 280 to 350 ° C. to wind the coil to recrystallize it after hot rolling, and then by cold rolling. Rolled to the final plate thickness, thereby obtaining an aluminum alloy rolled plate for a lithographic printing plate support having an average grain size of 60 μm or less in the direction perpendicular to the rolling direction of crystal grains on the plate surface. Than it is.

Further, the method for producing an aluminum alloy rolled plate for a lithographic printing plate support according to the third aspect of the invention is Cu0.00
01-0.03%, Ti 0.005-0.03%, Fe
0.1 to 0.5%, Si 0.05 to 0.20%, Mn 0.02 to 0.1%, Cr 0.02 to
An aluminum alloy containing 0.1% and one or more of Zr 0.02 to 0.1%, the balance of which is Al and inevitable impurities, is cast, and 50% is cast in the ingot.
After performing homogenizing treatment at a temperature within the range of 0 to 620 ° C. for 1 hour or more, when hot rolling is performed by rough rolling and finish rolling, the hot rough rolling start temperature is 380 to 450.
The temperature difference between the central portion in the sheet width direction and the edge portion in the sheet width direction during hot finish rolling is within 20 ° C.,
Further, the finish temperature of hot finish rolling is set within the range of 280 to 350 ° C., and the coil is wound up to be recrystallized at the end of hot rolling, and then cold rolled to a final plate thickness, thereby crystallizing the plate surface. It is characterized in that an aluminum alloy rolled plate for a lithographic printing plate support having an average grain size in the direction perpendicular to the rolling direction of 60 μm or less is obtained.

Further, the method for producing an aluminum alloy rolled plate for a lithographic printing plate support according to the invention of claim 4 is Cu0.
0001 to 0.03%, Ti 0.005 to 0.03%,
Fe 0.1-0.5%, Si 0.05-0.20% are contained, and Mn 0.02-0.1%, Cr 0.02-
0.1%, and one or more selected from Zr0.02 to 0.1%, and In0.0.
01-0.05%, Sn 0.001-0.05%, Pb
0.001-0.05%, Ni 0.001-0.05
%, And Be 0.0001 to 0.01%, and one or more of them, with the balance being Al and unavoidable impurities.
After performing homogenizing treatment at a temperature within the range of 0 to 620 ° C. for 1 hour or more, when hot rolling is performed by rough rolling and finish rolling, the hot rough rolling start temperature is 380 to 450.
The temperature difference between the central portion in the sheet width direction and the edge portion in the sheet width direction during hot finish rolling is within 20 ° C.,
Further, the finish temperature of hot finish rolling is set within the range of 280 to 350 ° C., and the coil is wound up to be recrystallized at the end of hot rolling, and then cold rolled to a final plate thickness, thereby crystallizing the plate surface. It is characterized in that an aluminum alloy rolled plate for a lithographic printing plate support having an average grain size in the direction perpendicular to the rolling direction of 60 μm or less is obtained.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION First, the reasons for limiting the components of the alloy used in the method for producing an aluminum alloy rolled plate for a lithographic printing plate support of the present invention will be explained.

Fe: If the Fe content is less than 0.1%, the crystal grain size during recrystallization becomes coarse, and the electrolytic surface-roughening pits become nonuniform. On the other hand, if the Fe content exceeds 0.5%, Al-
Fe-based and Al-Fe-Si-based coarse compounds increase,
Electrolytic surface roughening pit becomes non-uniform. Therefore, the Fe content is set within the range of 0.1 to 0.5%.

Si: If the Si content is less than 0.05%, the electrolytic surface roughening pits will be non-uniform. On the other hand, the Si content is 0.
If it exceeds 20%, the amount of Al-Fe-Si-based coarse compounds increases, the electrolytic surface-roughening pits become non-uniform, the burning resistance decreases, the severe ink smearing property decreases, and further, the electrochemical The color tone after surface roughening becomes too blackish and the commercial value is impaired. Therefore, the Si content is 0.05 to
It was set within the range of 0.20%.

Cu: Cu has a great influence on the electrolytic graining property. When the Cu content is less than 0.0001%,
Electrolytic surface roughening pit becomes non-uniform. On the other hand, if it exceeds 0.03%, the electrolytic surface-roughening pits become non-uniform, and the color tone after the surface-roughening treatment becomes too black and the commercial value is impaired. Therefore, the Cu content is set within the range of 0.0001 to 0.03%.

Ti: Ti also has a great influence on the electrolytic graining property, and also has a great influence on the structural state of the aluminum alloy ingot. When Ti is less than 0.005%,
Electrolytic surface roughening pits become non-uniform, and the crystal grains of the ingot are not refined to have a coarse grain structure, so that strip-shaped streaks occur in the macrostructure along the rolling direction, and electrochemical Even after the surface-roughening treatment, strip-shaped streaks remain, which is not preferable as a support for a lithographic printing plate. On the other hand, the Ti content is 0.03%
If it exceeds, not only the effect of refining the ingot structure is saturated, but also an Al—Ti-based coarse intermetallic compound is generated, and the electrolytic roughened surface becomes nonuniform. Therefore, the Ti content is set within the range of 0.005 to 0.03%.

In, Sn, Pb, Ni, Be: All of these have the effect of promoting electrolytic etching in the electrochemical graining treatment and forming uniform and fine electrolytic graining pits even with a low amount of electricity. It has an effect of improving the electrolytic graining property, and therefore, in the method for producing an aluminum alloy rolled plate for a lithographic printing plate support according to the inventions of claims 2 and 4, any one kind or two or more kinds are added. . Of these, In, Sn, Pb, and Ni do not have the above-mentioned effects if less than 0.001%, while 0.0
If the content exceeds 5%, fine electrolytic surface roughening pits are not formed, the corrosion resistance is significantly reduced, and general corrosion is likely to occur. Therefore, the contents of In, Sn, Pb, and Ni are all It was set within the range of 0.001 to 0.05%. On the other hand, Be has the effect of promoting electrolytic etching in the electrolytic graining treatment even with a smaller amount and forming uniform and fine electrolytic graining pits even with a low amount of electricity, but the Be amount is 0.000.
If it is less than 1%, the above effect is not obtained, while if it exceeds 0.01%, fine electrolytic surface roughening pits are not formed, so that the Be content is 0.0001 to 0.01.
Within the range of%.

Mn, Cr, Zr: All of these are elements that improve the heat softening resistance, that is, the burning resistance, and manufacture of the aluminum alloy rolled plate for a lithographic printing plate support according to the inventions of claims 3 and 4. Any one in the method
It was decided to add one species or two or more species. Mn, Cr,
If the added amount of Zr is less than 0.02%, the effect of improving the burning resistance is not exhibited, while if added in excess of 0.1%, the electrolytic graining property deteriorates. So M
All of n, Cr, and Zr were within the range of 0.02 to 0.1%.

In addition to the above elements, basically Al and inevitable impurities may be used.

In general, in an aluminum alloy plate, a small amount of Ti may be added alone or in combination with a small amount of B in order to refine the ingot crystal structure and prevent the texture and streaks of the rolled plate. Also in the aluminum alloy for a lithographic printing plate support of the present invention, it is permissible to add a trace amount of B together with Ti. However, the amount of B is 1
If it is less than ppm, the above effect cannot be obtained, while the amount of B is 5
If it exceeds 0 ppm, not only the effect of adding B is saturated, but also linear defects due to coarse TiB ₂ particles are likely to occur. Therefore, when adding B, the amount of B added is 1 to 50 ppm.
It is preferably within the range.

Other impurities include JIS 105
0 equivalent impurities (Mg0.05% or less, Zn0.05
% Or less, and 0.05% or less in total), the characteristics of the aluminum alloy as a lithographic printing plate support will not be impaired.

Further, in the method of the present invention, in order to obtain an aluminum alloy plate for a lithographic printing plate support having excellent electrolytic graining properties, it is necessary to appropriately adjust the grain size of the rolled plate (final plate). is there. That is, regarding the uniformity of the electrolytic graining pits, it is necessary that the average grain size of the crystal grains on the surface of the rolled plate in the direction perpendicular to the rolling direction is 60 μm or less. If this value exceeds 60 μm,
Color tone unevenness of a few mm is generated on the roughened surface to the extent that it can be visually recognized, and the value as a product is reduced.

Next, a method of manufacturing the aluminum plate for an lithographic printing plate support of the present invention will be described.

First, an aluminum alloy having the above-described composition is cast by a conventional method such as DC casting. Of course, casting may be performed by a continuous casting method using a driving mold.

The obtained ingot is homogenized at a temperature in the range of 500 to 620 ° C. As a result, the impurity element is diffused and the pits are made more uniform during the electrochemical graining treatment. Here, the holding time of the homogenization treatment may be set to an appropriate time depending on the size of the ingot and the like, but it is usually about 1 to 20 hours. If it is less than 1 hour, the effect of homogenizing treatment cannot be obtained, while if it exceeds 20 hours, the effect of homogenizing treatment is saturated, which is economically unfavorable.

After the homogenization treatment, the ingot is cooled once and then
Although heat treatment for hot rolling can be performed, it is also possible to cool to 380 to 450 ° C. after the homogenization treatment and start hot rolling as it is.

Next, hot rolling is performed. This hot rolling is usually performed by rough rolling and finish rolling, but the hot rough rolling start temperature is set in the range of 380 to 450 ° C. If the hot rough rolling start temperature is less than 380 ° C., recrystallization does not occur during hot rolling and the ingot structure remains, so if electrochemical roughening treatment is performed on the final rolled plate, Appearance unevenness (streaks) occurs in a band or streak, which is not preferable for the surface appearance quality of the printing plate. On the other hand, if the hot rough rolling start temperature exceeds 450 ° C., the recrystallized grains become coarse during hot rolling, and streak patterns are generated during the electrochemical graining treatment, and as a printing plate, The surface appearance quality is degraded. Therefore, hot rough rolling is performed with 38
It was decided to start at 0 to 450 ° C.

Further, in the finish rolling after the rough rolling in the hot rolling, it is necessary to set the end temperature within the range of 280 to 350 ° C.

The finish rolling end temperature is important for controlling the recrystallization state during the finish rolling or when the take-up coil is left as it is thereafter.
If the temperature is lower than 0 ° C, recrystallization does not occur during finish rolling or after being rolled up and left in a coil, and if the finish rolling end temperature exceeds 350 ° C, recrystallization occurs but the recrystallized grain size increases. As a result, streaks are finally generated when the electrochemical graining treatment is performed. Therefore, the finish rolling end temperature is set within the range of 280 to 350 ° C.

Further, in the hot finish rolling, it is necessary to control the temperature difference between the center in the sheet width direction and the end in the sheet width direction during the finish rolling so that it is within 20 ° C. That is, in the present invention, in order to improve streakability, it is necessary to recrystallize as uniformly and finely as possible in a state after hot finish rolling (a state in which a coil is wound). It is desirable to control the temperature distribution and the amount of reduction in the hot rough rolling and the hot finish rolling to be uniform, and particularly, the temperature distribution in the strip width direction in the finish rolling greatly affects the uniformity of the recrystallization behavior. Generally, the edge in the plate width direction is more likely to have a temperature drop than the center part in the plate width direction and is less likely to be recrystallized, and even if the edge part in the plate width direction is recrystallized, The recrystallized grain size varies depending on the temperature difference.
According to experiments conducted by the present inventors, when the temperature difference between the end portion and the central portion in the plate width direction during hot finish rolling is 20 ° C. or more, the crystal between the end portion and the central portion in the plate width direction is formed. It was found that the difference in grain size became remarkable, and a streak pattern, that is, a kind of streak, was generated in the vicinity of the boundary during the electrochemical graining treatment, which deteriorates the appearance quality of the product. Therefore, in the present invention, not only the end temperature is specified as 280 to 350 ° C. as the temperature condition in the hot finish rolling, but also the temperature difference between the central portion and the end portion in the strip width direction during the finish rolling is within 20 ° C. It was decided to control so that In addition, such a condition that the temperature difference is within 20 ° C.
Of course, it is maintained from the start to the end of finish rolling. Further, in order to keep the temperature difference in the strip width direction small during the finish rolling as described above, the reduction rate, the rolling speed, the temperature, pressure, and amount of the rolling oil in the strip width direction may be appropriately adjusted.

There is no particular limitation on the thickness of the hot-rolled sheet, but it is usually 1.0 to 4.5 mm.

As described above, for a hot-rolled sheet that has been uniformly and finely recrystallized in a state of being hot-rolled by rough rolling and finish rolling and wound into a coil, that is, in a state after hot rolling is completed. , Cold rolling to product thickness. This cold rolling is performed to obtain a required strength at the same time as finishing to a predetermined plate thickness, and a rolling rate of 65%.
You need to do this. If the cold rolling ratio is less than 65%, the product plate strength will be insufficient, and the handling property in the printing plate manufacturing process will be poor. In the case of the present invention, in order to save energy and costs, in cold rolling, the intermediate thickness is not sandwiched, and the hot rolled sheet is rolled to the final sheet thickness in one or several passes. The final plate thickness is 0.1
Plate thicknesses of ~ 0.5 mm are common.

For the plate rolled to the final plate thickness as described above, the flatness may be improved through a straightening line such as a roller leveler or a tension leveler.

In order to use the aluminum alloy plate for a lithographic printing plate support obtained as described above as a lithographic printing plate support, a surface roughening treatment is performed. The aluminum alloy sheet of the present invention is suitable for the electrochemical graining treatment (electrolytic graining) as described above, and the electrochemical graining treatment and the mechanical graining treatment and / or the chemical graining surface are performed. It is also suitable for combination with chemical treatment. The electrochemical graining treatment is suitable for producing a lithographic printing plate having excellent printability because it is easy to give fine irregularities to the surface of the aluminum alloy plate. This electrochemical surface roughening treatment is generally carried out in an aqueous solution mainly containing nitric acid or hydrochloric acid by using direct current or alternating current.

By such a surface roughening treatment, craters or honeycomb-shaped pits having an average depth of about 0.05 to 1 μm and an average diameter of about 0.2 to 20 μm are dispersed on the surface of the aluminum alloy plate by 30 to 100%. It can be generated with a density (area ratio). Here, in the electrochemical roughening treatment, the amount of electricity required to provide sufficient pits on the surface, that is, the product of the current and the energization time is an important condition, but from the viewpoint of energy saving. It is preferable to generate sufficient pits with a smaller amount of electricity. In the present invention, the conditions of the electrochemical surface roughening treatment are not limited and can be performed under general conditions, but in any case, the required amount of electricity can be significantly reduced. The required amount of electricity depends on the desired pit depth, diameter, and uniformity of dispersion and dispersion density, but is preferably 1
If it is in the range of 00 to 500 C / dm ² , a uniform and fine electrolytic rough surface can be obtained.

The mechanical surface roughening treatment in the case of combining the electrochemical surface roughening treatment and the mechanical surface roughening treatment is carried out on the surface of the aluminum alloy plate, generally with an average surface roughness Ra of 0.
35 to 1.0 μm, preferably 0.40 to 0.80 μm
To be done. Average surface roughness Ra is JISB
Although it is a factor defined by 0601-1994 that indicates the waviness of the surface of the support, the larger this is, the larger the unevenness is, and the better the water retention is. The conditions for the mechanical surface roughening treatment are not particularly limited, either, but Japanese Patent Publication No.
It can be performed according to the method described in the publication. Further, the chemical surface roughening treatment is not particularly limited and can be carried out according to a known method.

Subsequent to the roughening treatment, anodizing treatment is usually carried out in order to enhance the abrasion resistance of the surface of the aluminum alloy plate. The electrolyte used in this case may be any as long as it forms a porous oxide film. Generally, sulfuric acid, phosphoric acid, oxalic acid, chromic acid or mixtures thereof are used. The concentration of the electrolyte is appropriately determined depending on the type of electrolyte. The condition of the anodizing treatment varies considerably depending on the electrolyte, so it is difficult to specify, but generally the concentration of the electrolyte is 1 to 80% by mass,
Liquid temperature 5 to 70 ° C., current density 1 to 60 A / dm ² , voltage 1
˜100 V, electrolysis time 10 to 300 seconds.

In order to improve the stain resistance during printing, after electrochemical graining and washing with water, a slight etching treatment with an alkaline solution is performed, followed by washing with water.
An anodic oxide film may be formed by performing desmutting treatment with an acid that removes unnecessary substances (smut) from the alkali remaining on the surface of the aluminum plate, followed by washing with water and direct current electrolysis in sulfuric acid. Furthermore, you may perform hydrophilic treatment by a silicate etc. as needed.

A support for a lithographic printing plate can be obtained as described above. However, if the aluminum alloy plate for a support of the present invention is used, the pits produced by the roughening treatment can be deepened depending on the treatment conditions. It is possible to appropriately adjust the length and the diameter, and to form pits having a uniform size by uniformly dispersing the pits at a desired dispersion density. Further, the electrolytic treatment cost required to impart these characteristics can be significantly reduced.

Further, in order to use the support as a planographic printing plate, a photosensitive agent may be applied to the surface of the support and dried to form a photosensitive layer. The photosensitizer is not particularly limited, and those usually used for photosensitive lithographic printing plates can be used. Then print the image using squirrel film,
By carrying out development processing and gumming processing, a printing plate that can be attached to a printing machine can be obtained. Further, it is also possible to directly print an image using a laser or the like without using a film.

Any photosensitizer may be used as long as it has solubility or swelling property in a developing solution before and after exposure. Typical examples of the photosensitizer are listed below.

(1) Examples of the photosensitive layer positive photosensitive compound comprising an o-quinonediazide compound include o-quinonediazide compounds represented by o-naphthoquinonediazide compounds. As the o-naphthoquinonediazide compound, an ester of 1,2-diazonaphthoquinonesulfonic acid chloride and pyrogallol-acetone resin described in JP-B-43-28403 is preferable. US Pat. Nos. 3,046,120 and 3,188,2
Esters of 1,2-diazonaphthoquinone sulfonic acid chloride and phenol-formaldehyde resins described in No. 10 are also preferred. Other known o-naphthoquinonediazide compounds can also be used.

A particularly preferred o-naphthoquinonediazide compound is a compound obtained by reacting a polyhydroxy compound having a molecular weight of 1,000 or less with 1,2-diazonaphthoquinonesulfonic acid chloride. 1,2-diazonaphthoquinonesulfonic acid chloride at a ratio of 0.2 to 1.2 equivalents to 1 equivalent of hydroxyl groups of the polyhydroxy compound,
It is particularly preferable to react at a ratio of 0.3 to 1.0 equivalent. As the 1,2-diazonaphthoquinone sulfonic acid chloride, 1,2-diazonaphthoquinone-5-sulfonic acid chloride is preferable, but 1,2-diazonaphthoquinone-4-sulfonic acid chloride can also be used.

The o-naphthoquinonediazide compound is 1,
A mixture of 2-diazonaphthoquinonesulfonic acid chlorides having different positions and introduction amounts of the substituents is obtained, but the ratio of all the hydroxyl groups converted to 1,2-diazonaphthoquinonesulfonic acid ester in the mixture (completely ester It is preferable that the content of the compound is 5 mol% or more, particularly 20 to 90%.

Polymers having an o-nitrocarbinol ester group described in, for example, Japanese Patent Publication No. 56-2696 can also be used as a positive-working photosensitive compound without using an o-naphthoquinonediazide compound. Is. Furthermore, a compound that generates an acid by photolysis,
-C-O-C- group or -C-O-S dissociated by acid
A combination system with a compound having an i-group can also be used.
For example, a combination of a compound capable of generating an acid by photolysis with an acetal or an O, N-acetal compound (Japanese Patent Laid-Open No. Sho 4).
No. 8-89003), or a combination with an orthoester or amide acetal compound (JP-A-51-120714).
No.), a polymer having an acetal or ketal group in the main chain (JP-A No. 53-133429), and an enol ether compound (JP-A No. 55-1299).
No. 5), a combination with an N-acylimino carbon compound (JP-A-55-126236), and a polymer having an orthoester group in the main chain (JP-A-56-17345).
No.), in combination with a silyl ester compound (Japanese Patent Laid-Open No. Sho 60)
-10247) and a silyl ether compound (JP-A-60-37549, JP-A-60-121).
No. 446) and the like.

The ratio of the positive type photosensitive compound (including the combination system as described above) in the photosensitive composition of the photosensitive layer is 1
0 to 50 mass% is preferable, and 15 to 40 mass% is more preferable.

The o-quinonediazide compound alone can form the photosensitive layer, but it is preferably used together with a resin soluble in alkaline water as a binder.
Examples of the resin soluble in alkaline water include novolac resins, such as phenol-formaldehyde resin and m-
Cresol-formaldehyde resin, p-cresol-
Formaldehyde resin, m- / p-mixed cresol-formaldehyde resin, phenol / cresol mixed (m
-, P-, m- / p- mixed) -cresol-formaldehyde resin such as formaldehyde resin, phenol-modified xylene resin, polyhydroxystyrene, polyhalogenated hydroxystyrene, JP-A-51.
Acrylic resin containing phenolic hydroxyl group as disclosed in JP-A-34711, JP-A-2-866
Various alkali-soluble polymers such as an acrylic resin having a sulfonamide group and a urethane resin described in Japanese Patent Laid-Open Publication No. 2003-242242 can be contained. The alkali-soluble polymer preferably has a weight average molecular weight of 500 to 20,000 and a number average molecular weight of 200 to 60,000.

The alkali-soluble polymer is 7% of the total composition.
It is contained in an amount of 0 mass% or less. Further, U.S. Pat. No. 4,12
As described in US Pat. No. 3,279, it is obtained by polycondensation of formaldehyde with a phenol having an alkyl group having 3 to 8 carbon atoms as a substituent, such as t-butylphenol-formaldehyde resin and octylphenol-formaldehyde resin. It is preferable to use the resin in combination because it improves the oil sensitivity of the image.

The photosensitive composition should contain a cyclic acid anhydride in order to enhance sensitivity, a printout agent for obtaining a visible image immediately after exposure, a dye as an image colorant and other fillers. You can Cyclic anhydrides are described in US Pat.
115,128, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-endooxy-Δ4-tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride. , Chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic dianhydride, etc. are used. The cyclic acid anhydride has a content of 1 to 15 with respect to the total mass of the composition.
By including the material in the amount of% by mass, the sensitivity can be increased up to about 3 times. A typical example of the printing-out agent for obtaining a visible image immediately after exposure is a combination of a photosensitive compound that releases an acid upon exposure and an organic dye capable of forming a salt.

Specifically, o-described in JP-A-50-36209 and JP-A-53-8128
A combination of naphthoquinone diazide-4-sulfonic acid halogenide and a salt-forming organic dye, JP-A-53-36233, JP-A-54-74728, and JP-A-60-3.
626, JP 61-143748, JP 61-151644, and JP 63-58440.
There may be mentioned combinations of trihalomethyl compounds and salt-forming organic dyes described in Japanese Patent Application Laid-Open Publication No. 2003-242242. As the image colorant, dyes other than the above-mentioned salt-forming organic dyes can be used. Suitable dyes, including salt-forming organic dyes, are oil-soluble dyes and basic dyes.

Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 6.
03, Oil Black BY, Oil Black BS, Oil Black T-505 (all of them are manufactured by Orient Chemical Industry Co., Ltd.), Victoria Pure Blue, Crystal Violet (CI42555), Methyl Violet (CI42535), Rhodamine B (CI45170).
B), malachite green (CI42000), methylene blue (CI52015) and the like.
The dyes described in JP-A No. 62-293247 are particularly preferable.

The photosensitive composition is applied to the support by dissolving it in a solvent that dissolves the above components. As the solvent, ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-
Methoxy-2-propyl acetate, toluene, methyl acetate, methyl lactate, ethyl lactate, dimethylsulfoxide, dimethylacetamide, dimethylformamide,
Examples thereof include water, N-methylpyrrolidone, tetrahydrofurfuryl alcohol, acetone, diacetone alcohol, methanol, ethanol, isopropanol, diethylene glycol and dimethyl ether. These can also be mixed and used.

The above component (solid content) in the solution is 2 to 5
It is 0 mass%. The coating amount varies depending on the use, but in the case of a photosensitive lithographic printing plate, for example, the solid content is generally preferably 0.5 to 3.0 g / m ² . Although the photosensitivity increases as the coating amount decreases, the physical properties of the photosensitive film deteriorate.

The photosensitive composition contains a surfactant, for example, a fluorine-based surfactant as described in JP-A-62-170950, in order to improve coatability. The preferred content is 0.01 to 1 of the total photosensitive composition.
It is mass%, preferably 0.05 to 0.5 mass%.

(2) A photosensitive layer negative-working photosensitive diazo compound comprising a diazo resin and a binder is described in US Pat. No. 2,063,631 and US Pat.
Condensation product of diphenylamine-p-diazonium salt, which is a reaction product of a diazonium salt disclosed in 667,415, and an organic condensing agent having a reactive carbonyl group such as aldol and acetal, and formaldehyde ( A so-called photosensitive diazo resin) is preferably used.

Other useful condensed diazo compounds are disclosed in JP-B-49
-48001, Japanese Patent Publication No. 49-45322,
It is described in JP-B-49-45323. Since this type of photosensitive diazo compound is usually obtained in the form of a water-soluble inorganic salt, it can be applied as an aqueous solution. Further, a water-soluble diazo compound is reacted with an aromatic or aliphatic compound having one or more phenolic hydroxyl groups, sulfonic acid groups or both by the method described in JP-B-47-1167, It is also possible to use the product, a substantially water-insoluble photosensitive diazo resin.

The content of the diazo resin is 5 to 5 in the photosensitive layer.
It is preferable that the content is 0% by mass. When the content is low, the photosensitivity naturally increases, but the stability over time decreases. The optimum diazo resin content is about 8 to 20% by mass. On the other hand, as the binder, various polymers that can be used, and those containing a hydroxyl group, an amino group, a carboxyl group, an amide group, a sulfonamide group, an active methylene group, a thioalcohol group, and an epoxy group are preferable.

Specifically, British Patent No. 1,350,52
Shellac described in U.S. Pat. No. 1, British Patent 1,460,978 and U.S. Pat. No. 4,12.
Polymers containing hydroxyethyl (meth) acrylate units as the main repeating unit as described in 3,276, polyamide resins described in U.S. Pat. No. 3,751,257, British Patent 1st, 0
74,392, and phenolic resins such as polyvinyl formal resin, polyvinyl butyral resin, linear resins described in U.S. Pat. No. 3,660,097. Polyurethane resin, phthalated resin of polyvinyl alcohol, epoxy resin obtained from bisphenol A and epichlorohydrin, polymer containing amino group such as polyaminostyrene and polyalkylamino (meth) acrylate, cellulose acetate, cellulose alkyl ether, cellulose acetate phthalate, etc. Cellulose derivatives are included.

Compositions comprising a diazo resin and a binder may further include a pH indicator as described in GB 1,041,463, US Pat.
Additives such as phosphoric acid and dyes described in 6,646 may be incorporated.

The film thickness of the photosensitive layer is 0.1 to 30 μm, more preferably 0.5 to 10 μm. The amount of the photosensitive layer provided on the support (solid content) is from about 0.1 to about 7 g / ^{m 2,} preferably 0.5-4 g / ^{m 2.} After the planographic printing plate is imagewise exposed, a resin image is formed by a process including development by a conventional method. For example, in the case of a positive-working photosensitive lithographic printing plate having a photosensitive layer (A), after image exposure, US Pat. No. 4,259,434 and JP-A-3-903 have been used.
By developing with an aqueous alkaline solution as described in JP-A-88, the exposed portion of the photosensitive layer is removed to obtain a lithographic printing plate.

As the photosensitive layer, in addition to the above-mentioned examples,
It goes without saying that a photosensitizer capable of laser exposure may be used.

[0067]

EXAMPLES The present invention will be described more specifically by way of examples, but it goes without saying that the present invention is not limited to the following examples.

Example 1: Alloy No. 1 in Table 1 and Table 2 1 to N
o. Aluminum alloy having the chemical composition shown in 23 is melted and semi-continuously cast to 500 mm x 1200 mm
A 3500 mm ingot was cast. The ingot is subjected to homogenization heat treatment, gradually cooled to room temperature, chamfered by 10 mm on each side, heated and hot-rolled, and further cold-rolled without intervening intermediate annealing. The raw plate for a lithographic printing plate support having a thickness of 3 mm was finished. The plate temperature difference between the end and the center in the width direction during hot finish rolling was controlled by adjusting the rolling reduction, the rolling speed, the rolling oil temperature, the pressure difference of the rolling oil in the plate width direction, and the amount of rolling oil. Table 3 shows the detailed conditions of the homogenizing heat treatment and the hot rolling.

For the materials obtained by combining these various alloys and various manufacturing conditions, the following evaluation tests were conducted.

Grain size: Average grain size in the direction perpendicular to the rolling direction on the surface of the aluminum alloy sheet, observed by a polarizing microscope after anodizing with Barker's solution which is generally used for measuring the grain size of aluminum alloys. The particle size was determined by the cutting method.

Electrolytic graining property (electrochemical graining treatment property): The electrolytic graining property was evaluated by subjecting a base plate to a surface treatment as shown in Table 4. Table 4 shows each process.
The treatment was performed in order from the left side treatment, and washing was performed between each treatment. In this example, mechanical roughening with a brush was not performed. Here, in the alkaline etching treatments (1) and (2) in Table 4, the NaOH concentration was 26% by mass, the aluminum ion concentration was 6.5% by mass,
A solution having a liquid temperature of 65 ° C. was used. In the electrochemical graining treatment, a solution having a nitric acid concentration of 1% by mass and an aluminum ion concentration of 0.5% by mass was used as an electrolytic solution, and electrolysis was performed with an alternating current. The amount of electricity in this electrochemical graining treatment was 310 C / dm ² . The anodic oxidation treatment in Table 4 was performed with a direct current using a 15 mass% sulfuric acid solution as an electrolytic solution. The surface thus treated is observed with the naked eye and SEM,
The electrolytic graining property was evaluated. As for the evaluation, the case where the surface roughening was uniform was judged as pass (◯ mark), and the case where the surface roughening was not uniform was judged as fail (x mark).

Streak evaluation: The streak property of an aluminum alloy rolled plate for a lithographic printing plate support was originally determined by the electrochemical roughening treatment.
This should be evaluated by streak-like unevenness), but since this streak is derived from the macrostructure, the macrostructure is exposed by chemical etching, and it is determined whether streaks occur in the macrostructure or not. Ease of generating streaks during chemical surface roughening (streaks)
Can be evaluated. Therefore, it was decided to evaluate the streak property by the macro structure. That is, the surface of the rolled plate was chemically etched with aqua regia to reveal a macrostructure, and it was observed visually whether streaks exist or not. For evaluation, it was determined that there was no streak (good), the case where streak was weak was a little good (marked), and the strong streak was bad (bad).

Table 5 shows the results of the above evaluations.

[0074]

[Table 1]

[0075]

[Table 2]

[0076]

[Table 3]

[0077]

[Table 4]

[0078]

[Table 5]

As shown in Table 5, sample No. 1 according to the method of the present invention. 1-No. 4, No. 11-No. 17
It was found that all of them have not only good electrolytic graining property but also no streak generation and good streak property.

On the other hand, the sample No. 5 to No. 9
However, since the amounts of Cu, Ti, Si, and Fe were out of the ranges specified in the present invention, the electrolytic graining properties were inferior. Sample No. For 6, the Ti
Since the amount was small, the ingot structure could not be refined, and streaks occurred. Sample No. In the case of No. 10, since the amount of Fe was small, the recrystallized grains could not be refined after hot rolling and streaks occurred. Sample No. In No. 8, since the amount of Si was high, the solid solution amount of Fe was reduced, and the burning resistance was also reduced. Sample No. 18-No. 23 are Cu and T respectively
Since the amounts of i, In, Sn, Pb, and Ni were out of the ranges specified in the present invention, the electrolytic graining property was poor. Sample No. 19 has a small amount of Ti,
The ingot structure could not be refined and streaks occurred. Sample No. In No. 24, the electrolytic graining property was poor because the homogenization treatment temperature was low. Sample No. In No. 25, since the hot rolling start temperature was high and the finish rolling end temperature was high, the recrystallized grains in the hot rolling became coarse and streaks occurred. Sample No. In No. 26, since the hot rolling start temperature was too low, the finish rolling end temperature was also low, so that the hot rolling did not result in a completely recrystallized state and streaks occurred. Sample No. 27, No.
No. 28 had a plate temperature difference of 30 ° C. or more between the widthwise end portion and the center portion in finish rolling, and thus streaks were generated at the widthwise end portion.

Example 2: Alloy Nos. In Tables 6 and 7 24-
No. The aluminum alloy having the chemical composition shown in 36 was cast, homogenized, hot-rolled and cold-rolled in the same manner as in Example 1 to obtain a 0.3 mm thick lithographic printing plate support base plate. . The conditions for homogenization and hot rolling are as shown in Table 3.

For the materials obtained by combining these various alloys and various manufacturing conditions, the crystal grain size, electrolytic graining property and streak property were examined in the same manner as in Example 1. Further, in the case of Example 2, since Mn, Cr, and Zr for improving the burning resistance were added to the alloy, the burning resistance was examined as follows.

Burning resistance: For convenience, the material processed into JIS No. 5 test pieces was immersed in an oil bath at 270 ° C. for 7 minutes, and then a tensile test was performed to obtain 0.2% proof stress. If this value was 110 MPa or more, the burning characteristics were judged to be acceptable (marked with ◯).

Table 8 shows the results of the above evaluations.

[0085]

[Table 6]

[0086]

[Table 7]

[0087]

[Table 8]

As is clear from Table 8, the sample No.
29-No. 32, No. 37-No. 40's
It was found that all of them were excellent in electrolytic graining property and burning resistance, and streaks were not generated.

On the other hand, the sample No. 33-No.
35, No. 41, No. 42 are M respectively
n, Cr, Zr amount is more than the upper limit specified in the present invention,
Therefore, not only was the electrolytic graining property poor, but recrystallization did not occur after hot rolling, and streaks occurred. Sample No. 36, No. The 43 ones are
In both cases, since the plate temperature difference between the widthwise end portion and the central portion in the finish rolling was 30 ° C. or more, streaks were generated at the widthwise end portion.

[0090]

As is apparent from the above-mentioned embodiments, according to the method for producing an aluminum alloy rolled plate for a lithographic printing plate support according to the present invention, electrolytic graining property is excellent in a process without intermediate annealing. It is possible to obtain an aluminum alloy rolled plate for a lithographic printing plate, which simplifies the process as compared with the conventional method, saves energy and costs, and, even though the intermediate annealing is omitted, the electrochemical roughening is performed. It is possible to reliably suppress the generation of streaks during the surface treatment.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C22F 1/00 613 C22F 1/00 613 623 623 623 674 674 682 682 682 683 683 685 685Z 694 694B (72) Inventor Hirokazu Sawada 400 Kawajiri, Yoshida-cho, Haibara-gun, Shizuoka Prefecture Fuji Shashin Film Co., Ltd. (72) Inventor Akio Uesugi 400, Kawajiri, Yoshida-cho, Haibara-gun Shizuoka Prefecture F-term (reference) 2H114 AA04 AA14 DA04 EA08 FA01 GA02

Claims (4)

[Claims] 1. Cu 0.0001 to 0.03% (mas
s%, the same hereinafter), Ti 0.005 to 0.03%, Fe
0.1 to 0.5%, Si 0.05 to 0.20% is contained, the balance is cast from an aluminum alloy consisting of Al and inevitable impurities, and the cast ingot is heated at a temperature in the range of 500 to 620 ° C. After performing homogenizing treatment for 1 hour or more, when hot rolling is performed by rough rolling and finish rolling, the hot rough rolling start temperature is set in the range of 380 to 450 ° C., and the sheet width direction during hot finish rolling is performed. The temperature difference between the central portion and the plate width direction end portion is set to 20 ° C. or less, and further, the hot finish rolling end temperature is set to a range of 280 to 350 ° C. and wound on a coil to recrystallize after hot rolling, After that, it is rolled to a final plate thickness by cold rolling so that the average grain size of the crystal grains on the plate surface in the direction perpendicular to the rolling direction is 60.
A method for producing an aluminum alloy rolled plate for a lithographic printing plate support, which has excellent electrolytic graining properties and does not cause streaks, characterized by obtaining a rolled aluminum alloy plate for a lithographic printing plate support having a size of not more than μm. 2. Cu 0.0001 to 0.03%, Ti
0.005-0.03%, Fe0.1-0.5%, Si
0.05 to 0.20%, In 0.001
.About.0.05%, Sn 0.001 to 0.05%, Pb0.
001-0.05%, 0.001-0.05% Ni, and 0.0001-0.01% Be, and casts an aluminum alloy containing at least one of Al and unavoidable impurities. Then, 500 to 6 in the ingot
After performing homogenizing treatment at a temperature in the range of 20 ° C. for 1 hour or more, when hot rolling is performed by rough rolling and finish rolling, the hot rough rolling start temperature is set in the range of 380 to 450 ° C. The temperature difference between the central portion in the sheet width direction and the edge portion in the sheet width direction during hot finish rolling is set to 20 ° C. or less, and the hot finish rolling end temperature is set to a range of 280 to 350 ° C. It is recrystallized after the hot rolling, and then cold rolled to the final thickness.
As a result, an aluminum alloy rolled plate for a lithographic printing plate support having an average grain size of 60 μm or less in the direction perpendicular to the rolling direction of crystal grains on the plate surface is obtained, which is excellent in electrolytic graining property and streaks. A method for producing a rolled aluminum alloy plate for a lithographic printing plate support without generation of scratches. 3. Cu 0.0001 to 0.03%, Ti
0.005-0.03%, Fe0.1-0.5%, Si
0.05 to 0.20%, and Mn 0.02 to
0.1%, Cr 0.02-0.1%, and Zr 0.0
2 to 0.1% of one or more of them is cast, and an aluminum alloy having the balance of Al and unavoidable impurities is cast, and the ingot is heated to a temperature in the range of 500 to 620 ° C. for 1 hour or more. After performing the homogenization treatment, when hot rolling is performed by rough rolling and finish rolling, the hot rough rolling start temperature is set in the range of 380 to 450 ° C., and the center portion in the plate width direction during hot finish rolling is used. The temperature difference from the end in the sheet width direction is set to 20 ° C or less, and the hot finish rolling end temperature is set to a range of 280 to 350 ° C, and the coil is wound to recrystallize after hot rolling, and then cold rolling. Rolling to a final plate thickness by rolling, thereby obtaining an aluminum alloy rolled plate plate for a lithographic printing plate support having an average grain size of 60 μm or less in a direction perpendicular to the rolling direction of crystal grains on the plate surface. That, electrolytic graining property and excellent in burning resistance and manufacturing method of generating free lithographic printing plate support aluminum alloy rolled sheet of streaks. 4. Cu 0.0001 to 0.03%, Ti
0.005-0.03%, Fe0.1-0.5%, Si
0.05 to 0.20% and Mn 0.02
0.1%, Cr 0.02-0.1%, and Zr 0.0
2 to 0.1%, and one or more selected from In 0.001 to 0.05%, Sn0.
001-0.05%, Pb 0.001-0.05%, N
i 0.001-0.05%, and Be 0.0001-
An aluminum alloy containing one or more of 0.01% and the balance of Al and unavoidable impurities is cast, and the ingot is homogenized for 1 hour or more at a temperature in the range of 500 to 620 ° C. When hot rolling is performed by rough rolling and finish rolling after the treatment, the hot rough rolling start temperature is set in the range of 380 to 450 ° C., and the center portion and the plate width in the plate width direction during hot finish rolling are set. The temperature difference from the end of the direction is 20 ° C. or less, and the finish temperature of hot finish rolling is set in the range of 280 to 350 ° C. to wind the coil to recrystallize it after hot rolling, and then by cold rolling. Rolled to a final plate thickness, thereby obtaining an aluminum alloy rolled plate plate for a lithographic printing plate support having an average grain size of 60 μm or less in the direction perpendicular to the rolling direction of crystal grains on the plate surface. The method of electrolytic graining property and excellent in burning resistance and without occurrence of streaks lithographic printing plate support aluminum alloy rolled sheet.