JPS60215728A - Blank aluminum alloy plate for printing - Google Patents

Abstract

PURPOSE:To provide a titled blank alloy plate having excellent surface treatability, burning property, etc. by subjecting a blank Al alloy material controlled respectively in the contents of Si, Fe, Cu, Ti and Mg as an impurity and having the content of Si in the specific relation according to the content of Cu and Mg and intermediate annealing temp. to cold rolling after intermediate annealing. CONSTITUTION:A blank Al alloy material contg. respectively, by weight %, <=0.08% Si, 0.05-1.0% Fe, <=0.03 Cu, <=0.10% Ti and <=0.03% Mg as an impurity and satisfying the following conditions is prepd.: The content of Si (%) is controlled within the range satisfying the formulas I , II according to the content of Cu (%), the content of Mg (%) and intermediate annealing temp. T ( deg.C) and the difference between the content of Cu and the content of Mg is controlled within the range satisfying the formula III as the above-mentioned conditions. Such blank Al alloy material is subjected to cold rolling at 20-95% reduction ratio after intermediate annealing for <=24hr at 300-500 deg.C, by which the intended blank Al alloy plate for printing is obtd. The blank Al alloy plate has excellent resistance to ink staining in addition to the above-described characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aluminum alloy 111j (referred to as an aluminum alloy base plate for J:X lower printing) used as a support for offset printing or a support for lithographic printing.

Conventionally, aluminum alloy base plates for printing generally have a plate thickness of 0.1 to 0.5 am and are graded (F).
A 1050P, A1100P, or A3003P
Rolled plates such as These printing plates are
Usually, the surface of the ingot obtained by semi-continuous casting is removed with a solidifying agent, homogenized if necessary, heated to a predetermined temperature and hot rolled, and then 20 to 95% Cold rolling at a processing rate of 1 to obtain an intermediate thickness, or
2. Directly cast the coil under IJX by continuous casting,
The plate is cold-rolled to an intermediate thickness without going through a hot rolling process, and then intermediate annealing is performed on the plate with the intermediate thickness.
It is manufactured by final cold rolling at a processing rate of .

In order to actually use such a printing aluminum alloy base plate for printing, the surface of the base plate is first processed by a mechanical method, a chemical method, an electrochemical method, or a combination of two or more methods. After the surface is roughened, it is preferably subjected to polar oxidation treatment, then coated with a photosensitizer, exposed, and subjected to plate-making processes such as development.Then, in order to improve the strength of the photosensitive film and improve printing durability. 250-300
Short-time heat treatment at °C (this is called burning treatment)
The ink is then wrapped around the cylindrical plate cylinder of a printing press, the ink is applied to the image area in the presence of dampening water, and after being transferred to a rubber blanket, it is printed on the paper surface.

The printing aluminum alloy base plate used as described above is required to have the following characteristics (A), (B), and (C).

(A) It is possible to uniformly form irregularities through the surface roughening treatment, there is no unevenness after the surface roughening, and an appropriate color tone is exhibited. The ability to roughen the surface uniformly and appropriately in this manner is hereinafter referred to as "surface treatability."

(B) There is little decrease in strength due to burning treatment.

Hereinafter, such performance will be referred to as "burning property".

(C) Ink stains do not occur in non-image areas during printing.

This is hereinafter referred to as "ink stain resistance."

Among these characteristics, if the surface treatment properties of (A) are poor, the color tone after roughening becomes whitish or too black, and in some cases, color unevenness occurs, resulting in a decrease in commercial value. In addition, since the unevenness after roughening has a great effect on printing durability and image clarity, it is fundamentally important for printing plates to have good surface treatment properties and uniform unevenness after roughening. It is a condition. When the surface roughening treatment is carried out by electrolytic etching, it is natural that the condition of the roughened surface changes variously depending on the electrolytic conditions and the type of etching solution, but the phenomenon is caused by the electrochemical interaction between the aluminum surface and the electrolytic solution. Since it is a reaction, it goes without saying that the contribution of one characteristic of the material itself (surface treatability) cannot be ignored. However, in the case of conventional aluminum alloy base plates for printing, surface treatment properties for roughening have not been explored and studied, and the reality is that although they do not necessarily have sufficient surface treatment properties, there are few. Ta.

On the other hand, regarding the burning property (B), there is a method in which the image area is strengthened by exposing and developing a PS plate using an aluminum alloy plate as a support in the usual way, and then heat-treating it at a high temperature (so-called burning treatment). It is said that it is effective in Japanese Patent Publication No. 44-27243 and Japanese Patent Publication No. 44-272.
The heating temperature and time for such a burning process depend on the type of resin forming the image, but the heating temperature and time for such a burning process are described in detail in Japanese Patent No.
A range of 7 minutes is customary. However, in recent years, it has become desirable to perform the burning process at a higher temperature in order to improve printing durability and shorten the burning process time. However, when the conventionally used aluminum alloy plates are heated to a high temperature of 280°C or higher, a recrystallization phenomenon occurs, resulting in an extremely low strength and a loss of stiffness, making it extremely difficult to handle the plate. There are disadvantages such as it becomes impossible to set the plate on the machine, and it is difficult to register the colors of the plate in multicolor printing. Therefore, it can withstand burning treatment at high temperatures.

There is a strong desire to develop an aluminum alloy plate with high heat resistance, that is, an aluminum alloy base plate for printing with excellent burning resistance.

Furthermore, regarding the ink staining property (C), printing plates must basically avoid ink from adhering to non-image areas during printing and staining the printed matter. According to research by the present inventors, this ink stain during printing is caused by
It was found that the main cause was localized corrosion caused by the reaction of the printing plate with dampening water.

This invention was made against the background of the above circumstances, and has the above-mentioned three characteristics, namely, surface treatment property, burning property,
Another object of the present invention is to provide an aluminum alloy base plate for printing that is excellent in all respects in terms of ink stain resistance.

In order to achieve the above-mentioned object, the present inventors conducted extensive experiments and studies on the chemical composition of the aluminum alloy blank that affects the above-mentioned properties and the intermediate annealing thread 4' during the manufacturing process of the blank. As a result of stacking, S in the material has a negative effect on surface treatment properties.
It was discovered that il, Cul and Mgl have a strong influence on burning property, Sil in the material and intermediate annealing temperature have a strong influence on ink staining property, and Sit has a strong influence on ink staining property. It's arrived.

In other words, first of all, regarding surface treatment properties, the greater the amount of 3i in the material, the more uniformly rough the surface can be obtained, and the range of the amount of 3i in which this uniformly rough surface can be obtained depends on the ratio of the amount of CLI and the amount of MIJ in the material. It is influenced by the difference, that is, the amount of (Cu-Mg), and (Qu
-vo) It has been found that the larger the amount, the wider the range in which a good rough surface can be obtained, even down to lower Sil. On the other hand, regarding burning properties, conversely, the less stm in the material, the more
It was also found that the higher the intermediate annealing temperature, the less the decrease in strength after the burning process. Furthermore, regarding ink stain resistance, it has been found that the less Sit in the material, the better the ink stain resistance. And from these findings, (
S that satisfies the three properties of surface treatment properties, burning properties, and ink staining properties at the same time in the condition range of Cu-Mg)≧0.
It was discovered that an i amount range (however, a Si amount range depending on the amount of Cu-MO and the intermediate annealing temperature) existed, and this invention was completed.

Specifically, the aluminum alloy base plate for printing of the present invention is obtained by intermediate annealing of an aluminum alloy material at 300 to 550°C for 24 hours or less, and then cold rolling at a processing rate of 20 to 95%. plate, the alloy composition is sto,
oa% or less, Fe0005~1.0%, CuO003%
Below, TiO, 10% or less, M130 as an impurity
．． 03% or less, the remainder being considered as unavoidable impurities and A1,
and st amount (si%) is Cu amount (Cu amount), rv
Depending on the lo content (MU%) and the intermediate annealing temperature T (°C), the Cu
An aluminum alloy base plate for printing that has excellent three properties of surface treatment properties, burning properties, and ink staining properties, characterized in that the difference between the Mg content and the Mg content is within a range that satisfies the following formula (3). be.

(Si amount) ≧0.08-4 ((Cu amount) −(I
a%) )... (1) (Si amount)≦2 T/625- 1.28, (2) 0
≦((Cu amount) -()j9%))≦0.03-(3
) Furthermore, the aluminum alloy base plate for printing of the present invention will be explained in detail.

First, regarding surface treatment properties, as mentioned above, the SI in the material
The more I is, the more uniform the unevenness of the surface after roughening treatment becomes.
In addition, the Sil for that purpose is influenced by the difference between Cul and Mg amount, that is, (Cu-M(1)fi), and (cu-Mu
) As the amount of I increases, uniform unevenness can be obtained up to a lower amount of 3i. As a result of detailed experiments by the present inventors, in order to obtain excellent surface treatment properties, Stl in the material (C++
-Mg) It has been found that it is necessary to satisfy the above formula (1) depending on the pot. 5iffi of this equation (1)
and the range of intermediate annealing temperature T, (GO-M!J
) is 0.01%, the area is above line AB in FIG. In the region below the straight line AB, the unevenness of the roughened surface after the roughening treatment becomes irregular, making it difficult to form a uniform roughened surface. Furthermore, this straight line AB
The position of (CLI - IVHI ) is determined according to formula (1)
It goes up and down depending on the amount, and in particular, as the amount of (Cu-MO) increases, the straight line AB goes downward.

Next, the burning property is related to the amount of Si and the intermediate annealing temperature, and the lower the 3i amount and the higher the intermediate annealing temperature, the less the decrease in strength after the burning process. According to detailed experiments by the inventors, the amount of 3i is the intermediate annealing temperature T (℃)
In relation to, if the range of the above formula (2) is satisfied,
It has been found that the decrease in strength after the burning process can be suppressed to a level that does not pose a practical problem. If the range of this equation (2) is illustrated, it is the area to the right of the straight line CD in FIG.

In the region to the left of the straight line CD, the strength decreases significantly after the burning treatment, and for example, after the burning treatment at 270° C. for 7 minutes, the 0.2% yield strength becomes 5 ka/- or less, which is not preferable.

Furthermore, regarding ink stain resistance, the smaller the amount of Sl in the material, the less ink stain in non-image areas.

According to detailed experiments conducted by the present inventors, it has been found that in order to obtain good ink stain resistance, the amount of Sl in the material needs to be 0.08% or less. This region where 3i is 0.08% or less is a region below the straight line EF in FIG. If the Si content is more than 0.08%, ink will adhere to non-image areas during printing, making printed matter likely to become smudged.

Furthermore, the intermediate annealing temperature T is 300 to 5, as will be explained later.
It is necessary to keep the temperature within a range of 50° C., and this range corresponds to the area to the right of the straight line IGH and to the left of the straight line IJ in FIG. In the end, the above conditions are shown in Figure 1.
tf, 4 Straight 11NA B, CD, EFi Shaded area surrounded by 1J, i.e. PI -P2- Pa
- 3i in which the area within the range of PI satisfies the three properties mentioned above, namely surface treatment properties, burning properties, and ink staining properties.
amount and intermediate annealing temperature range.

As mentioned above, the position of the straight IAB moves up and down depending on the amount of (Cu-Mo) according to equation (1), and when the amount of (Cu-Mg) decreases to 0%, the position of the straight IAB coincides with the straight line EF. Put it away. Therefore, for the Pl-P2-Pa-PI region to actually exist, the amount of (Cu-Mo) must be 0.
% or more. Conversely, if the amount of (Cu-Mg) increases, the straight line AB will move downward, and the region satisfying the three characteristics will expand. However, as will be described later, the maximum Cu amount is 0003% and the minimum Ml)I is 0%, so (CL
I-Ml) amount is at most 0.03%. therefore(
For Cu-Mlj)I, as shown in equation (3), 0.
The range was defined as 0.03% to 0.0%. Note that (Ctl-Mo
) If the amount is 0.03% or less, it will not have any effect on burning properties and ink staining properties.

Furthermore, the reasons for limiting the components other than Si among the material components of the printing aluminum alloy base plate of the present invention will be explained.

If Fe is less than 0.05%, surface treatment properties are poor and mechanical properties are also insufficient. On the other hand, if F(l) exceeds 1.0%, the ink stain resistance deteriorates and the color tone after surface roughening treatment becomes too dark, which is not preferable. Therefore, Fe content is 0.05 to 1.0%
was within the range of

TI is added for the purpose of making the crystal grains of the ingot uniform and fine, but if it exceeds 0.10%, its effect will be saturated and it will only lead to an increase in costs.
．． It was limited to 10% or less. For this purpose, as a means of adding i, rather than using an Al-Ti master alloy, /l
The effect is greater when the '-Ti-8 master alloy is used. In this case, B is contained, but it is preferable to suppress the B content to 0.02% or less in order to prevent the occurrence of linear defects due to ■+82 particles.

Cu is added to improve surface treatment properties, but 0.
If Cu is added in an amount exceeding 0.03%, the ink staining properties will deteriorate, so the upper limit of Cu is set to 0.03%.

Mg, which is an impurity, deteriorates surface treatment properties, but Mg
If it is within 0.03%, it coexists with an appropriate amount of Cu and does not deteriorate surface treatment properties. If MOo exceeds 0.3%, surface treatment properties will deteriorate even if it coexists with Cu.
Mg needs to be regulated to 0.03% or less.

The impurities that are unavoidably contained in trace amounts do not have any particular adverse effect on surface treatment properties, ink staining properties, and burning properties.

Next, to explain the manufacturing process conditions of the printing aluminum alloy base plate of the present invention, the process conditions before the intermediate annealing process do not particularly affect surface treatment properties, burning properties, and ink staining properties, and therefore, normal methods You should adopt. In other words, in the process up to intermediate annealing, the surface of the semi-continuously cast ingot is usually removed with a solidifying agent, then homogenized if necessary, and heated to a predetermined temperature before hot rolling. The coil is hot-rolled and then cold-rolled at a processing rate of 20 to 95%, or a continuously cast coil with a plate thickness of 1211 mm or less is directly cast and then cold-rolled as is without going through the hot-rolling process. adopt. After reaching the intermediate thickness in this way, it is subjected to intermediate annealing at 300 to 550°C for up to 24 hours, followed by final cold rolling at a working rate of 20 to 95% to obtain the necessary mechanical strength. administer. The reasons for limiting the intermediate annealing conditions are as follows. In other words, if the intermediate annealing temperature is less than 300°C, sufficient recrystallization will not occur, making it unsuitable for intermediate annealing.On the other hand, if the intermediate annealing temperature is higher than 550°C, secondary recrystallization will occur, causing the recrystallized grains to become significantly coarser, and the surface The oxidation causes unevenness and blisters, making it unsuitable as a base plate for printing. Note that the intermediate annealing temperature is actually regulated also by the relationship with the amount of Sl in the two materials as described above. On the other hand, the intermediate annealing time is set to a maximum of 24 hours because if it exceeds 24 hours, the annealing effect will be saturated and it will only be economically disadvantageous.

The effects of this invention will be clarified with examples below.

Examples Various inventive alloys and comparative alloys shown in sample numbers 1 to 11 in Table 1 were melted and semi-continuously cast to 450 -Xl.
It was cast into a 20011 x 3500111 slab. After applying a solidifying agent of 7 μm on each side to the slab,
Homogenization treatment at 50°C for 12 hours followed by 500°C
Hot rolling was started, and a hot-rolled plate with a thickness of 5 mm was finished.

Next, after cold rolling to a plate thickness of 1.2 mm, this was intermediately annealed in a stationary annealing furnace at various temperatures shown in Table 2. The temperature increase rate during this stationary annealing was approximately 50° C./Hr, and the holding time after reaching the annealing temperature was 2 hours. 'Next, this intermediate annealed coil was cold rolled to a thickness of 0.3111 m to obtain a base plate for offset printing. The 3i content and intermediate annealing temperature of these samples 1 to 11 are plotted and shown as X marks in FIG. In addition, in Fig. 2, IIA-P4
-P3-8 is Si according to the above formula (1) when the amount of (Cu - MO') is 0.01%, but the upper and lower limits are 0.04%
), and the line A'-P4'-Pg'-B is (Cu
When -Mg)l is 0.015%, the lower limit of Sin (0.02%) is shown by the above formula (1) for Niochel.

After mechanically roughening each blank plate obtained in this example by brushing, it was heated in a 10% NaOH aqueous solution for 5
Preliminary etching was performed at 0° C. for 1 minute, followed by electrochemical surface roughening treatment by performing AC electrolysis at 35° C. using a nitric acid etching solution. Then 15%H280
An anodized film of IJJI is formed by anodizing treatment in 4 baths, and then a photosensitizer is applied to form 88 for offset printing.
The plate was manufactured. After performing prescribed exposure and development processing on this, 2
Barung treatment was performed at 80°C for 7 minutes. Using the original plate thus obtained, a printing test of 100,000 copies was conducted in the presence of dampening water.

Table 2 also shows the results of investigating the performance of these invention alloys and comparative alloys. Regarding the surface treatment properties, it was checked whether the uniformity of the unevenness of the roughened surface after the electrochemical roughening treatment was obtained, and the results were classified as O: good, and X: poor. The strength after burning was expressed as b value. Regarding ink stain resistance, we checked the stains in the non-image area after printing 100,000 copies, ○...good,
...Distinguished by defect.

As shown in Table 2, the aluminum alloy base plates for printing within the scope of the present invention (sample numbers 1.2.3) have excellent surface treatment properties, burning properties, and ink stain resistance. It is clear that On the other hand, among the comparative example alloys (sample numbers 4 to 11), sample numbers 4.5.8.10.
Sample No. 11 has poor surface treatment properties because the amount of Si does not satisfy the formula (1) above in relation to (Cu-Mg)I, and sample No. 7.8.9.10 has a 3i amount that does not meet the intermediate annealing temperature. r
Since the above equation (2) was not satisfied in lJ luck, the yield strength after the burning treatment was poor, and sample number 6.9.10.
Sample No. 11 has a sun of more than 0.08%, and therefore has poor ink stain resistance. Therefore, it can be seen that in order to satisfy all of the surface treatment properties, burning properties, and ink staining properties, it is necessary to satisfy all the conditions of the present invention.

In the above embodiments, intermediate annealing was performed by stationary batch annealing, but continuous annealing, in which annealing is performed by passing the coil through a heating furnace maintained at a high temperature while unwinding the coil, is also possible. Of course, it is also possible to apply intermediate annealing according to the method.

As is clear from the above description, the printing aluminum alloy base plate of the present invention has excellent surface treatment properties against roughening treatment, and the surface roughening treatment property allows unevenness to be formed uniformly and evenly. At the same time, it is possible to obtain an appropriate color tone through surface roughening treatment, and it also has excellent burning properties, resulting in less decrease in mechanical strength after burning treatment. It is now possible to perform a burning process between short poems, and it also has excellent ink stain resistance, effectively preventing printed matter from staining due to ink adhering to non-image areas during printing. When it was printed using a printing plate, a good print was obtained. Therefore, the aluminum alloy plate for printing of the present invention is extremely useful as a support for offset printing or a support for planographic printing.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the condition range of Sil (wt%) in the material and intermediate annealing temperature ('C) in the aluminum alloy material of the present invention, and Fig. 2 is a diagram showing the condition range of Sil (wt%) in the material and intermediate annealing temperature ('C) in the aluminum alloy material of the present invention.
FIG. 2 is a diagram showing the amount and intermediate annealing temperature plotted on a diagram similar to FIG. 1; Applicant: Sky Aluminum Co., Ltd. Fuji Photo Film Co., Ltd. Agent: Yutaka, Patent Attorney 1) Hisashi Take (and 1 other person) Figure 1 Nakajyu It4 Friends (・C)

Claims (1)

[Scope of Claims] In an aluminum alloy base plate for printing obtained by subjecting an aluminum alloy material to intermediate annealing at 300 to 550°C for 24 hours or less and then cold rolling at a processing rate of 20 to 95%, the alloy composition of the material However, S i O, 08% or less (weight %, same below), f:e 0005-1.0%, CD 0.
03% or less, Tl0010% or less, Mg as an impurity
O, 03% or less, the remainder being unavoidable impurities and AI, and the amount of Si (81%) is as follows depending on the amount of C1l (CLI%), the amount of fvta (tvlo%), and the intermediate annealing temperature T ('C) It is within the range that satisfies formulas 1) and (2),
Furthermore, an aluminum alloy base plate for printing, characterized in that the difference between the CLI amount and the Mg amount is within a range that satisfies the following formula (3). (81%)≧0.08-4 ((C11%)-(141
1%))...(1) (81%)≦2 T/625- 1.28-(2)0
; ((C1%)-(M1%)) ≦0.03-(3
)