JP2777349B2 - Aluminum alloy plate for printing plate and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy plate for a printing plate used as a support for offset printing or the like, and in particular, to form a uniform electrolytically roughened surface by a short electrolytic roughening treatment. The present invention relates to an aluminum alloy plate for a printing plate and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, in offset printing, an aluminum or aluminum alloy (hereinafter referred to as aluminum) plate is generally used as a support. This aluminum plate for a printing plate is obtained by subjecting the surface of an aluminum plate to a surface roughening treatment in order to impart adhesion to a photosensitive film and water retention of a non-image portion. Conventionally, mechanical treatment methods such as a ball polishing method and a brush polishing method have been used as the surface roughening method. Recently, however, hydrochloric acid or an electrolytic solution mainly containing hydrochloric acid, or nitric acid or nitric acid has been mainly used. Electrolytic surface roughening method for electrochemically roughening the surface of an aluminum plate using an electrolytic solution to be treated, and furthermore, a method combining the aforementioned mechanical treatment method and this electrolytic surface roughening method. Is being used. This is because the rough surface plate obtained by the electrolytic surface roughening method is suitable for plate making and also has excellent printing performance.In the electrolytic surface roughening method, the aluminum alloy plate is formed into a coil shape. This is because it is suitable for continuous processing.

As described above, it is required that the surface of the aluminum alloy plate to be roughened be formed with uniform irregularities (pits) by the roughening treatment. In an aluminum alloy plate for a printing plate on which uniform irregularities are formed,
Adhesion with the photosensitive film and water retention are improved, and excellent image clarity and printing durability can be obtained. In recent years, in order to reduce the cost of the surface roughening treatment, there is a strong demand for the development of an aluminum alloy plate capable of forming uniform irregularities in a shorter time or with a smaller amount of electricity.

An aluminum alloy plate suitable for such electrochemical surface roughening treatment can be obtained by adding Fe, Cu and other trace elements.
e: 0.2 to 1.0% by weight, Cu: 0.1 to 2.0
Weight% and 1 selected from Sn, In, Ga and Zn
An aluminum alloy sheet containing 0.05 to 0.1% by weight of at least one element has been proposed (JP-A-58-21).
0144). This aluminum alloy plate is characterized by a high dissolution rate with respect to chemical etching.

Further, as an aluminum alloy plate having excellent roughness uniformity, Fe: 0.05 to 0.5% by weight, Mg:
0.1 to 0.9% by weight, Si: 0.2% by weight or less, and Cu: 0.05% by weight or less, and one or more elements selected from the group consisting of Zr, V and Ni. 0.0
An aluminum alloy plate containing 1 to 0.3% by weight and the balance consisting of Al and unavoidable impurities has been proposed (JP-A-62-230946).

Further, as an aluminum alloy plate having good strength and uniformity of pits, Mg: 0.30 to 3% by weight, Fe: 0.15 to 0.50% by weight, Ni: 0.0
05 to 0.30% by weight and Ti: 0.01 to 0.1
0 wt%, Si, Cu, and Mn are each regulated to 0.20 wt% or less, and the balance is Al and the content of each element is 0.10 wt% or less. Has been proposed (JP-A-63-30294).

Further, while forming a uniform rough surface,
As an aluminum alloy plate that prevents contamination of non-image areas and improves tone reproducibility and color tone (brightness) of image areas, F
e: 0.1 to 1.0% by weight, Si: 0.02 to 0.
There has been proposed an aluminum alloy plate containing 15% by weight and an impurity of Cu: 0.003% by weight or less, with the balance being unavoidable impurities other than Al and Cu (Japanese Patent Publication No. 47545/1994).

Furthermore, Fe: 0.1 to 0.5% by weight, Si: 0.03 to 0.30% by weight, Cu: 0.0
01 to 0.03% by weight, Ni: 0.001 to 0.0
3% by weight, Ti: 0.002 to 0.05% by weight and G
a: containing 0.005 to 0.020% by weight, and
An aluminum alloy plate having a total content of a and Ti of 0.010 to 0.050% by weight has been proposed (JP-A-3-177528). In this aluminum alloy plate, streaks and irregular image quality unevenness, which are streak-like unevenness in surface roughness, are improved, and the rough surface is uniform, so that contamination of non-image areas is prevented.

[0009]

However, recently,
In order to reduce the cost, an improvement in the electrolytic processing speed is required, and there is a need for an aluminum plate that can form uniform pits in a short electrolytic surface roughening treatment. That is, even when the electrolytic surface roughening treatment time is short and the amount of electricity is small, deep independent pits are uniformly formed and the unetched portion (the unetched portion of the aluminum plate surface) is formed on the aluminum plate. Is not expected to occur. However, the conventional aluminum plate has not satisfied such a demand.

The present invention has been made in view of such a problem, and even if the electrolytic surface roughening treatment is performed for a short time, the roughened pits are uniformly formed on the electrolytic roughened surface, and the pits of the pits are formed. An object of the present invention is to provide an aluminum alloy plate for a printing plate having a substantially constant size and a method for manufacturing the same.

[0011]

The aluminum alloy plate for a printing plate according to the present invention comprises Fe: 0.20 to 0.6% by weight, Si: 0.03 to 0.15% by weight, Ti: 0.0
05 to 0.05% by weight and Ni: 0.005 to 0.
20% by weight, and one or more elements selected from the group consisting of In, Sn, and Pb in an amount of 0.1% per element.
001 to 0.020% by weight, and 0.001 to 0.020% by weight in total, with the balance being Al and unavoidable impurities.

The Ti content is preferably at least 0.010% by weight. Further, B preferably contains 1 to 50 ppm by weight.

According to a method of manufacturing an aluminum alloy plate for a printing plate according to the present invention, an aluminum alloy ingot having a composition according to any one of claims 1 to 3 is added to an aluminum ingot having a composition of 500 to 63.
The homogenization treatment is performed at a temperature of 0 ° C., and then the starting temperature is 40
It is characterized by performing hot rolling at 0 to 450 ° C.

[0014] After the hot rolling step, a cold rolling step and an intermediate annealing step may be provided. Further, a leveler straightening step may be provided after the cold rolling step.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have conducted intensive studies to obtain an aluminum alloy plate in which uniform roughening pits are formed even when performing electrolytic surface roughening treatment in a short time. As a result, the following facts were found. That is, among the alloy elements contained in the aluminum alloy plate, in addition to appropriately adjusting the contents of Fe and Si conventionally added, an appropriate amount of Ni and Ti are added, and further, from In, Sn and Pb. It has been found that it is effective to appropriately adjust the content of one or more elements selected from the group and to make the total amount appropriate. Further, by adding B as needed, the etching property of the aluminum alloy plate can be further improved. By making the content of each element appropriate as described above, it is possible to obtain roughened pits having good uniformity even in a short electrolytic roughening time.

First, the reasons for limiting the composition of the aluminum alloy plate for a printing plate according to claim 1 will be described.

Fe (iron): 0.20 to 0.6% by weight Fe has an action of forming uniform pits on the roughened electrolytic surface. Fe is an element that combines with other elements in an aluminum alloy to form an Al-Fe eutectic compound.
This eutectic compound has the effect of reducing the size of recrystallized grains and the effect of forming a uniform electrolytic rough surface. If the Fe content is less than 0.20% by weight, the number of reaction initiation points of the electrolytic surface-roughening pits is insufficient, and an unetched portion is generated. On the other hand, F
If the e content exceeds 0.6% by weight, the roughened electrolytic surface becomes non-uniform due to the formation of coarse compounds. Therefore, the Fe content is set to 0.20 to 0.6% by weight.

Si (silicon): 0.03 to 0.15 weight
% Si forms an Al-Fe-Si-based intermetallic compound and acts as a nucleus for recrystallization between passes in hot rolling, and thus has an effect of miniaturizing recrystallized grains during hot rolling. . When the Si content is less than 0.03% by weight, this effect is small, and the streak evaluation after the printing plate support is deteriorated. On the other hand, when the Si content exceeds 0.15% by weight, the roughened electrolytic surface becomes non-uniform due to the formation of a coarse compound. Therefore, the Si content is 0.03 to 0.15% by weight.
And

Ni (nickel): 0.005 to 0.2
0% by weight of Ni has the function of making the electrolytic rough surface uniform. Ni is Fe
Binds to other elements in the aluminum alloy as in
-An element that easily forms a Ni-based eutectic compound. Further, since Ni is electrochemically nobler than Fe, uniform independent pits are easily formed. For this reason, by adding Ni, a uniform roughened surface can be obtained by a short-time electrolytic surface roughening treatment.

If the Ni content is less than 0.005% by weight,
An unetched portion occurs on the rough electrolytic surface. On the other hand, when the Ni content exceeds 0.20% by weight, a coarse compound is formed,
The electrolytic rough surface becomes non-uniform. Therefore, the Ni content is 0.1.
005 to 0.20% by weight.

Ti (titanium): 0.005 to 0.05
The Ti-B master alloy has a function of refining the ingot structure to refine the crystal grains by weight, preferably 0.010% by weight or more . If the Ti content is less than 0.005% by weight, the grain refinement is insufficient. Also,
Ti has the effect of making the electrolytic rough surface uniform, in addition to the above-described miniaturization effect, similarly to the other components described above. In order to sufficiently obtain this effect, the Ti content is preferably 0.010% by weight or more. Ti content 0.010% by weight
If the value is less than the above range, the etching is not sufficiently performed, and an unetched portion tends to remain. On the other hand, when the Ti content exceeds 0.05% by weight, a non-uniform electrolytic rough surface is formed due to the formation of a coarse compound. Therefore, the Ti content should be 0.005 to 0.05% by weight, preferably 0.010% by weight.
Above.

In (indium), Sn (tin) and Pb
One or more elements selected from the group consisting of (lead): 1 element
0.001 to 0.020% by weight per element In, Sn and Pn exist in a solid solution state in the aluminum alloy, and make the aluminum matrix electrochemically low to reduce the potential difference between the aluminum matrix and the intermetallic compound. It has the effect of adjusting and making the electrolytic rough surface uniform.
If the content of at least one element selected from the group consisting of In, Sn, and Pb is less than 0.001% by weight per element, this effect is insufficient, and an unetched portion occurs. On the other hand, if the content of In, Sn, or Pb exceeds 0.020% by weight, the entire surface of the aluminum alloy plate has a molten surface, and a non-uniform electrolytic rough surface is formed. Therefore,
The content of at least one element selected from the group consisting of In, Sn and Pb is 0.001 to 0.0 per element.
20% by weight.

Content of In, Sn and Pb: 0.
001 to 0.020% by weight As described above, In, Sn and Pb have an effect of making the electrolytic rough surface uniform. However, if the total content of In, Sn and Pb is less than 0.001% by weight, this effect is insufficient. On the other hand, if the total content of In, Sn, and Pb exceeds 0.020% by weight, the entire dissolved surface is formed, resulting in a non-uniform electrolytic rough surface. Therefore, the contents of In, Sn and Pb are set to 0.001 to 0.020% by weight in total.

The aluminum alloy plate for a printing plate according to claim 3 contains B in addition to the above-mentioned chemical components.

B (boron): preferably 1 to 50
The amount ppm Ti-B master alloy as described above acts as a grain refiner. This crystal grain refining action is caused by an increase in the refined nuclei due to an increase in the amount of Ti-B particles due to a decrease in the amount of solute Ti. The present inventors have found that, in addition to this effect, an increase in the number of Ti-B particles has an effect of making the electrolytic rough surface uniform.

When the B content is less than 1 ppm by weight, etching pits tend to be uneven due to insufficient electrolysis. On the other hand, when the B content exceeds 50 ppm by weight, a coarse compound is formed, and the coarse compound forms streak-like deep pits, so that the electrolytically roughened surface becomes uneven. Therefore, when B is contained, the content is 1 to 50 ppm by weight.
It is preferable that

In the present invention, Cu, Zn, Ga and the like are considered as unavoidable impurities.
If it is less than the weight%, the effect of the present invention is not adversely affected.

In the method for producing an aluminum alloy plate for a printing plate according to the present invention, the aluminum alloy ingot having the above-mentioned composition is subjected to a homogenization treatment at a temperature of 500 to 630 ° C., and then a starting temperature of 400 to 450 ° C. Hot rolling is performed at a temperature to obtain an aluminum alloy plate for a printing plate. When the aluminum alloy plate for a printing plate thus obtained is subjected to electrolytic surface roughening treatment, the unetched portion is small, and
The pit size becomes uniform.

The reason for limiting the numerical values of the homogenization treatment temperature and the hot rolling start temperature in the method for producing an aluminum alloy plate for a printing plate will be described.

Homogenization temperature: 500 to 630 ° C. If the homogenization temperature is less than 500 ° C., the aluminum alloy ingot is insufficiently homogenized. In this case, the roughened electrolytic surface becomes non-uniform. On the other hand, when the homogenization treatment temperature exceeds 630 ° C., the crystal grain size becomes coarse, so that the macrostructure becomes coarse, and streaks, which are streaks, are generated. Therefore, the homogenization temperature is set to 500 to 630 ° C.

Hot rolling start temperature: 400 to 450 ° C. When the hot rolling start temperature is less than 400 ° C., the structure becomes non-uniform, and the electrolytically roughened surface of the obtained aluminum alloy plate becomes non-uniform. . On the other hand, the hot rolling start temperature is 450
If the temperature exceeds ℃, crystals grow between each pass of hot rolling,
Streaks occur. Therefore, the hot rolling start temperature is 4
00 to 450 ° C.

The hot rolling may be started after cooling the aluminum ingot to a temperature of 400 to 450 ° C. after the above-mentioned homogenization treatment. May be started after the aluminum alloy ingot having the reduced temperature is again heated to a temperature of 400 to 450 ° C.

After the completion of the hot rolling, the obtained aluminum alloy sheet is subjected to one or more times of cold rolling while performing intermediate annealing as necessary to obtain an aluminum alloy sheet for a printing plate having a predetermined thickness. obtain. In this case, a leveler correction step may be provided.

[0034]

EXAMPLES Examples of the present invention will be described below in comparison with comparative examples that depart from the scope of the claims. First,
An example (first example) of the aluminum alloy plate for a printing plate according to claim 1 will be described.

First Example An ingot of each aluminum alloy (Examples 1 to 4 and Comparative Examples 1 to 16) having the chemical composition shown in Table 1 below was face-polished to a thickness of 480 mm and a temperature of 610 ° C. The steel is subjected to a homogenization treatment at a temperature of 4 hours, then hot-rolled with the starting temperature set at 410 ° C., and further subjected to cold-rolling, intermediate annealing and cold-rolling in order to obtain an aluminum sheet having a thickness of 0.3 mm. An alloy plate was obtained.

[0036]

[Table 1]

Next, each of the aluminum alloy plates manufactured as described above was subjected to degreasing and neutralization cleaning under the processing conditions 1 or 2 shown in Table 2 below, and then subjected to AC electrolytic surface roughening treatment. Further, in order to remove oxides and the like formed by electrolysis, desmutting treatment was performed. After the end of this desmutting treatment, each aluminum alloy plate was washed with water and dried, cut out to a predetermined size, and used as a cut plate. Note that 1 dm ^{2 in} Table 2 is 0.01 m ² .

[0038]

[Table 2]

A cut plate of each aluminum alloy plate after a series of roughening treatments was surface-observed with a scanning electron microscope (SEM) at a magnification of 350 times, and the area of the visual field was 0.0
A photograph was taken so as to be 2 mm ² . From the obtained photograph, the unetched rate was calculated by the following mathematical formula 1.

[0040]

## EQU1 ## Unetched rate (%) = area of unroughened part / total area × 100

From this calculation result, the unetched rate is 5.
0% or less: ◎ (excellent), exceeding 5.0% to 8.0
% Or less (good), the unetched rate is 8.0%
Is evaluated as x (defective), and the unetched portion was evaluated.

The roughened surface of each cut plate was observed and photographed by using a scanning electron microscope at a magnification of 500 times. The total length is 100
A cm line was drawn and the size (diameter) of the pit below the line was measured. Those having a difference in size between the smallest pit and the largest pit of 5 μm or less were evaluated as having good uniformity (good) and those having a size larger than 5 μm were evaluated as having poor uniformity (poor).

Further, each aluminum alloy plate (rolling direction 1)
The surface of 5 cm × 10 cm in the vertical direction of rolling × 2 sheets = 3 dm ² ) was chemically etched with aqua regia to evaluate the length of the streaks. The case where the length of the stripe pattern in the rolling direction was less than 1 cm was evaluated as ○ (streak evaluation: good) and the case where the length was 1 cm or more was evaluated as x (streak evaluation: poor). Table 3 below shows the evaluation of streaks, unetched portions, and uniformity.
In each example and comparative example, each evaluation under processing condition 1 and each evaluation under processing condition 2 were the same.

[0044]

[Table 3]

As shown in Table 3, in Examples 1 to 4, since the content of each element is within the range specified by the present invention, any of the streak evaluation, the unetched portion evaluation, and the uniformity evaluation was evaluated. Was also good.

On the other hand, in Comparative Example 1, since the Si content was less than the range specified in the present invention, which was 0.01% by weight, the recrystallization was insufficiently refined and the streak was prolonged. In Comparative Example 2, since the Si content was 0.19% by weight, which was larger than the range specified in the present invention, a coarse compound was formed and the size of the pits varied.

In Comparative Example 3, the Fe content was 0.1
Since it was as small as 6% by weight, the number of reaction initiation points of the electrolytic surface-roughening pits was insufficient, and there were portions that were not etched on the surface of the aluminum alloy plate. Further, in Comparative Example 4, since the Fe content was as large as 0.67% by weight, a coarse compound was formed, the size of the pits varied, and the uniformity was poor.

In Comparative Example 5, since the Ni content was as small as 0.003% by weight, an unetched portion was formed. On the other hand, in Comparative Example 6, since the Ni content was as large as 0.213% by weight, a coarse compound was formed and the uniformity was poor.

In Comparative Example 7, since the Ti content was as small as 0.002% by weight, the cast structure was not sufficiently refined.
Streaks are longer. On the other hand, in Comparative Example 8, since the Ti content was as large as 0.069% by weight, a coarse compound was formed and the uniformity of the pits was poor.

In Comparative Example 9, of In, Sn and Pb, although In was added, the content was 0.0
Since the content was as low as 004% by weight, the total content of In, Sn and Pb was 0.0004% by weight. For this reason, the effect of adjusting the potential difference between the aluminum matrix and the intermetallic compound was insufficient, and an unetched portion occurred.
Also, the streak evaluation was poor. On the other hand, Comparative Example 1
At 0, the In content is as high as 0.0028% by weight,
In, Sn, and Pb content is 0.0028% by weight in total.
And the entire surface was dissolved, resulting in poor uniformity.

In Comparative Example 11, the Sn content and In,
Since the total content of Sn and Pb was as small as 0.0004% by weight, an unetched portion occurred. On the other hand, in Comparative Example 12, since the Sn content and the total content of In, Sn and Pb were as large as 0.031% by weight, the size of the pits varied, and the uniformity was poor.

In Comparative Example 13, the Pb content and the total content of In, Sn and Pb were 0.0003% by weight.
Therefore, an unetched portion was generated. On the other hand, in Comparative Example 14, since the Pb content and the total content of In, Sn and Pb were as large as 0.026% by weight, the uniformity was poor.

In Comparative Example 15, the In content was 0.000
1% by weight, the Sn content is 0.0003% by weight, and the Pb content is 0.0001% by weight.
The total content of n, Sn and Pb was 0.0005% by weight, which was less than the range specified in the present invention, and an unetched portion was formed on the surface of the aluminum alloy plate. On the other hand, Comparative Example 16
In, the In content is 0.009% by weight, the Sn content is 0.009% by weight, and the Pb content is 0.005% by weight.
Although both are within the range specified by the present invention, I
Since the total content of n, Sn and Pb was 0.023% by weight, which was more than the range specified in the present invention, the uniformity was poor.

Next, an embodiment (second embodiment) of the aluminum alloy plate for a printing plate according to claim 3 will be described.

Second Example Ingots of each aluminum alloy having the chemical composition shown in Table 4 below (Examples 5 to 10 and Comparative Examples 17 and 18) were added to the first ingot.
As in the example, face milling, homogenization treatment, hot rolling, cold rolling, intermediate annealing and cold rolling were sequentially performed to obtain a sheet thickness of 0.3.
mm was obtained. The comparative examples 1 to 16 of the first embodiment can be made comparative examples of the second embodiment.

[0056]

[Table 4]

Next, similarly to the first embodiment, each aluminum alloy plate was degreased under the processing conditions 1 and 2 shown in Table 2 above.
Neutralization washing, AC electrolytic surface roughening treatment and desmutting treatment were performed. After the end of the desmutting treatment, each aluminum alloy plate was washed with water and dried, cut to a predetermined size to obtain a cut plate, and various tests were performed on the cut plate in the same manner as in the first embodiment. The etching part evaluation and the uniformity evaluation were investigated. The results obtained are shown in Table 5 below.

[0058]

[Table 5]

As shown in Table 5 above, in Examples 5 to 10, since the content of each element is within the range specified in the present invention and the B content is a predetermined amount,
The etching was uniformly applied to every corner of the surface of the aluminum alloy plate, and the evaluation of the unetched portion was extremely good as compared with that of the first embodiment.

On the other hand, in Comparative Example 17, the B content was 60 ppm by weight, which was larger than the range specified in the present invention, so that the electrolytically roughened surface became non-uniform and the uniformity was poor. In Comparative Example 18, the B content was 0.5 wt pp.
m, which is less than the range specified in the present invention, none of the streak evaluation, the unetched portion evaluation, and the uniformity evaluation was particularly excellent.

Next, an embodiment of a method for manufacturing an aluminum alloy plate for a printing plate according to the present invention will be described. Table 1 above
An ingot of an aluminum alloy having a chemical composition similar to that of Examples 1 to 4 of Example 4 and Example 5 of Table 4 was chamfered to a thickness of 480 mm, and then homogenized under the conditions shown in Table 6 below. And hot rolling, and further cold rolling, intermediate annealing and cold rolling to obtain an aluminum alloy plate having a thickness of 0.3 mm (Examples 11 to 15 and Comparative Examples 19 to 22).

The obtained aluminum alloy plate was subjected to AC electrolytic surface roughening treatment under the same conditions as in the first embodiment described above, and then cut out to obtain a cut plate. The roughened surface of the cut plate was observed at a magnification of 350 times using a scanning electron microscope (SEM), and a photograph was taken so that the area of the visual field was 0.02 mm ² . From this photograph, the non-etching rate was obtained from the above equation (1). ◎ when the unetched rate is 5.0% or less
(Excellent) ○ The case of more than 5.0% and less than 8.0%
(Good), x when the unetched rate exceeds 8.0%
An unetched part was evaluated as (defective).

Further, the roughened surface was observed at a magnification of 500 times using a scanning electron microscope (SEM), and a photograph was taken. From the obtained photograph, the uniformity was evaluated in the same manner as in the first example. That is, those having a difference in size between the smallest pit and the largest pit larger than 5 μm were evaluated as having poor uniformity (poor) and those having a difference of 5 μm or less were evaluated as having good uniformity (good).

The aluminum alloy plate obtained as described above (rolling direction 15 cm × rolling vertical direction 10 cm × 2)
(3 dm ² ) was chemically etched with aqua regia to evaluate the streak length. The case where the length of the stripe pattern in the rolling direction was less than 1 cm was evaluated as ○ (streak evaluation: good) and the case where the length was 1 cm or more was evaluated as x (streak evaluation: poor). Table 6 below shows evaluations for streaks, unetched portions, and uniformity.

[0065]

[Table 6]

The chemical compositions 1 to 5 in Table 6 indicate that the chemical compositions are the same as those in Examples 1 to 5 described above.

As shown in Table 6 above, Examples 11 to 15
In the test, streaks, unetched portions, and uniformity were all good.

On the other hand, in Comparative Example 19, since the homogenization treatment temperature was 478 ° C., which was lower than the temperature specified in the present invention, the homogenization was insufficient and the streak evaluation was poor. In Comparative Example 20, since the homogenization treatment temperature was 645 ° C., which was higher than the temperature specified in the present invention, the crystal grains became coarse. For this reason, the macrostructure became coarse, and the streak evaluation was poor.

In Comparative Example 21, the hot rolling start temperature was 37
Since the temperature was 3 ° C., which was lower than the temperature specified in the present invention, the structure became non-uniform and the streaks became longer. On the other hand, in Comparative Example 22, since the hot start temperature was 468 ° C., which was higher than the range specified in the present invention, crystals grew between each pass in hot rolling and streaks occurred.

[0070]

As described above, since the aluminum alloy plate for a printing plate according to the present invention contains a predetermined chemical component, even if the electrolytic surface roughening treatment is performed for a short time, the surface is roughened. The pits are uniformly distributed on the surface, the size of each pit is substantially constant, and the streak is short.

In the method for producing an aluminum alloy plate for a printing plate according to the present invention, since the homogenization treatment temperature and the hot rolling start temperature are appropriate, uniform roughening pits can be obtained after the electrolytic surface roughening treatment. An aluminum alloy plate for a printing plate in which the generation of streaks is extremely suppressed can be manufactured.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-177528 (JP, A) JP-A-3-122241 (JP, A) JP-A-62-230946 (JP, A) JP-A-58-58 210144 (JP, A) JP-A-4-325644 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C22C 21/00 B41N 1/08 C22F 1/04

Claims (6)

(57) [Claims] 1. Fe: 0.20 to 0.6% by weight, S
i: 0.03 to 0.15% by weight, Ti: 0.005 to 0.05% by weight and Ni: 0.005 to 0.20% by weight, further selected from the group consisting of In, Sn and Pb One or more of the selected elements is added in an amount of 0.001 per element.
To 0.020% by weight, and a total amount of 0.001 to 0.02
An aluminum alloy plate for a printing plate, containing 0% by weight, with the balance being Al and unavoidable impurities. 2. The aluminum alloy plate for a printing plate according to claim 1, wherein the Ti content is 0.010% by weight or more. 3. The aluminum alloy plate for a printing plate according to claim 1, further comprising B: 1 to 50 ppm by weight. 4. An aluminum alloy ingot having a composition according to claim 1, wherein the aluminum alloy ingot has a composition of 500 to 63.
The homogenization treatment is performed at a temperature of 0 ° C., and then the starting temperature is 40
A method for producing an aluminum alloy plate for a printing plate, wherein hot rolling is performed at 0 to 450 ° C. 5. The method for producing an aluminum alloy plate for a printing plate according to claim 4, further comprising a cold rolling step and an intermediate annealing step after the hot rolling step. 6. The method for producing an aluminum alloy plate for a printing plate according to claim 5, further comprising a leveler correcting step after the cold rolling step.