JP3068410B2 - Method for producing aluminum plate for photosensitive lithographic printing - Google Patents

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 plate for photosensitive lithographic printing, and more particularly to a method for producing an aluminum plate for photosensitive lithographic printing wherein at least two opposing edges of the aluminum plate are improved. Things.

[0002]

2. Description of the Related Art Conventionally, when manufacturing an aluminum plate for photosensitive lithographic printing, first, a sheet-like or coil-like aluminum plate is prepared, and this is mechanically and / or coiled.
Alternatively, the surface is electrochemically roughened (polished). Next, if necessary, surface etching, anodic oxidation treatment, hydrophilic treatment, etc. are performed, and then cut (cut) to a predetermined size and then coated with a photosensitive solution, or coated with a photosensitive solution and then reduced to a predetermined size. The method of cutting is adopted. As the cutting means, a rotary shear, a flying shear, a down cut shear, an up cutter shear, a slitter, a sheet cutting machine (guillotine) and the like are generally used at present.

For example, when a product B is obtained by cutting an aluminum plate A using a slitter 51 as shown in FIGS. 7 and 8, the shapes of the blades used for the upper blade 52 and the lower blade 53 and the blades used at the time of use. Position is a flat blade (also referred to as a right angle blade) 52a
And flat blade 53a, countersunk blade (also called acute angle blade)
52b and a countersunk blade 53b, or a flat blade 52
a and a countersunk blade 53b so that the upper blade 52 is disposed (set) outside and inside with respect to the product B, and the portions C on both sides are unnecessary portions as edges (also called ears). ing. In FIG. 9, reference numeral 54 denotes a photosensitive layer.

[0004]

However, in the above-mentioned conventional method of manufacturing an aluminum plate for photosensitive lithographic printing, the upper blade 52 in use is used regardless of which cutting means including the slitter 51 is used. And the lower blade 53 are not in a proper positional relationship, so the flat blades 52a, 53a and the plate blade 52b,
Irrespective of the combination of 53b, among the edges (ends) S of the cut product B, there is a disadvantage that burrs (projections) D are formed on the front surface or the back surface of one edge as shown in FIG. Was.

When the lithographic plate is printed on a printing machine in a state in which such burrs D are formed, ink tends to be applied to the rim portion, and especially, roll-shaped paper is printed using a rotary press such as newspaper printing. When printing continuously, the ink on the edge was transferred to the paper because the width of the printing plate was smaller than the width of the paper, and this often appeared as stains around the newspaper. .

As a method for preventing the above-mentioned dirt, for example, a method has been proposed in which a corner at the end of an aluminum plate is shaved with a file or a knife (Japanese Patent Publication No. 57-467).
No. 54) In this case, although there is a certain effect when the number of prints increases, there is a disadvantage that the printing plates must be taken out one by one and cut off, which is not suitable for mass processing.

A method has also been proposed for desensitizing the edge of an aluminum plate before or after performing image forming exposure and development of a photosensitive printing plate (Japanese Patent Publication Sho 62).
In this case, although the effect is certainly obtained at the beginning of printing, the desensitizing effect is gradually reduced with the increase in the number of prints, so that dirt is generated or used in the desensitizing process. There is a drawback in that the desensitizing liquid permeates toward the edge of the plate, which results in poor development and causes contamination.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and has as its object to provide a photosensitive device which does not cause stains around the printed matter even at the beginning of printing or even when the number of copies is increased. production side of sexual lithographic aluminum plate
Is to provide a law .

Another object of the present invention is to provide a method for producing the above-mentioned aluminum plate for photosensitive lithographic printing, which is suitable for mass production.

[0010]

In order to solve the problems of the prior art, according to the present invention, there is provided a slitter having a pair of upper and lower blades, a coil-shaped or sheet-shaped aluminum plate for wide photosensitive lithographic printing. the in producing a product by cutting into a predetermined size, performing a blade on the front Symbol slitter arranged to come outside of the product with respect to the lower blade photosensitive Rights
The method for producing an aluminum plate for plate printing, wherein
Use a flat blade for the lower blade of the upper and lower blades of the
Using a countersunk blade with a slightly angled top blade
Aluminum plates for lithographic printing are cut .

Further, in the present invention, the upper blade and the upper blade
The gap between the lower blade and the aluminum plate to be cut is 2 to 2
Spread by 20%, or use the upper and lower blades
Set the overlap in the range of 0.5-3.0mm
Have you line.

The aluminum plate for photosensitive lithographic printing of the present invention is obtained by cutting a coiled or sheet-shaped aluminum plate for wide planographic printing having a photosensitive layer into a predetermined width by a slitter having a pair of upper and lower blades. The slitter used in this case refers to a machine that combines several sets of rotary blades and cuts a coil material or a sheet material into a predetermined width.

When cutting a wide aluminum plate in a coil shape, the product cut into a predetermined width is wound as it is, or cut and then cut into a product by a flying shear or a rotary shear. And
There is a method in which cutting is performed in two or more parts, and if necessary, edge cutting is also performed at the same time and wound as it is.

When a wide aluminum sheet is cut, the sheet is cut into a predetermined width one by one.
Alternatively, two or more divisions are performed from one sheet, and if necessary, edge cutting is also performed at the same time to produce a product.

When a large number of products are to be manufactured, usually, FIG.
An aluminum plate A is pulled out from a coiled aluminum plate X as shown in FIG. 1 and an upper blade 2 and a lower blade 3 which are rotatable up and down on the aluminum plate A are provided.
And the lower blade 3 to cut it with scissors and wind it up to form a coiled aluminum plate Y, or, as described above, continue to cross cut to produce a product. At this time, the rotation speed of the upper blade 2 and the lower blade 3 may be rotated at the same speed as the flow speed of the aluminum plate A (for example, 60 m / min), slightly earlier, or may be changed depending on the tension of the aluminum plate A. It is made to rotate around.

A method for producing an aluminum plate for photosensitive lithographic printing according to the present invention will be described with reference to FIG. In the manufacturing method of the present invention, two sets of slitters 1 each including a pair of upper and lower blades 2 and 3 are prepared. Then, the upper blade 2 is arranged and cut with respect to the lower blade 3 so that each of them is located outside the product B. In this case, the two opposite edges of the product B are connected to the photosensitive layer 4 on the surface as shown by S in FIG.
It is cut to be curved to the opposite side (lower side).

The edge of the aluminum plate A of the present invention is
As a method of cutting while bending in the range of 150 μm,
As shown in FIG. 2, the upper blade 2 of the slitter 1 is arranged outside the product B with respect to the lower blade 3, and more preferably, the upper blade 2
The clearance (clearance) between the upper blade 2 and the lower blade 3 is increased by 2 to 20% of the thickness of the aluminum plate A to be cut, or the bite (overlap) between the upper blade 2 and the lower blade 3 is reduced by 0.5.
The setting is performed in a range of up to 3.0 mm.

The cross section of the edge of the aluminum plate A cut in this way is as shown in FIG. 4, where the S portion is the edge and is formed by bending the dimension L below the surface. The width dimension M of the edge S referred to in the present invention is set to be equal to or less than the thickness of the aluminum plate A to be cut.

The bending dimension L of the edge S is 10 to 10.
In the range of 150 μm, more preferably 30 to 100 μm, and if it is 10 μm or less, the ink easily accumulates on the edge S, and the edge of the plate tends to be stained.
Above μm, burrs (protrusions) projecting downwards become too large, and the smoothness (planarity) of the aluminum plate A is impaired, or the plate cylinder of a printing machine on which the aluminum plate A is mounted is undesirably damaged.

The upper and lower blades 2 of the slitter 1 to be used are
The shape and angle of the bend also differ in the form of 3, but the flat blade is used for the lower blade 3 , and the upper blade 2 is either a slightly angled countersunk blade or a two-stage blade with slightly different angles. <br/> that have been used.

FIG. 5 shows a manufacturing method according to the present invention in which four or more slitters 1 are used to cut two or more products B of a predetermined width at a time from a wide aluminum plate A. FIG. In this case, similarly to the unnecessary portion C of the edge, the unnecessary portion E occurs in the middle.

The lower side of the edge S of the aluminum plate A is a portion H which is bent downward as shown in FIG.
However, if the bending dimension L is 150 μm or less, there is no problem of damaging the smoothness of the aluminum plate A and the plate cylinder of the printing press as described above, and the portion is crushed as shown in FIG. You may. The cross sections of these edges S can be observed and measured with a high magnification microscope or an electron microscope.

Further, the edge S of the aluminum plate A cut by the manufacturing method of the present invention can be desensitized with a desensitizing liquid.

The aluminum plate A used in the production method of the present invention is preferably first subjected to graining treatment for a lithographic printing plate. This graining process is generally graining (polishing, surface roughening) by mechanical or electrical methods.
Or a chemical etching or a combination of these processes.

Next, an anodic oxidation treatment is performed, usually in a sulfuric acid or phosphoric acid bath, whereby an anodic oxide film is formed on the surface of the aluminum plate A. After the anodic oxidation treatment is performed in this way, a hydrophilic treatment is performed as necessary.

The photosensitive layer 4 is provided on such an aluminum plate A.
The photosensitive layer 4 is not particularly limited, and is conventionally used as a photosensitive layer in a photosensitive printing plate material, for example, a layer composed of a diazo resin and a hydrophobic resin, an O-quinonediazide compound and an alkali. It is possible to use one composed of a soluble resin, one composed of a photopolymerizable or photocrosslinkable composition, one composed of a photoconductive composition, and the like.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments.

Example 1 First, a coiled aluminum plate (material 1050 according to JIS) having a thickness of 0.3 mm and a width of 460 mm is prepared.
Then, after the coiled aluminum plate was degreased with alkali, the surface was polished with a nylon brush while applying an aqueous suspension of silica powder, and then thoroughly washed with water.

Then, a 20% caustic soda solution at 70 ° C. was poured for 10 seconds, and the surface of the coiled aluminum plate was etched at 4 g / m ² , washed with running water and washed in a 1% hydrochloric acid bath. 160 coulomb / dm
Electropolishing was carried out with the quantity of electricity of ² and washed with water.

Also, the surface of the coiled aluminum plate is etched by pouring a 20% caustic soda solution at 70 ° C., further washed with water, and anodized in a 10% sulfuric acid aqueous solution at 30 ° C. An oxide film of 2.0 g / m ² was formed.

After washing with water, the substrate was immersed in an aqueous solution containing 5% of JIS No. 3 sodium silicate at 70 ° C. for 10 seconds, washed with water and dried.

On the aluminum plate thus obtained, a photosensitive solution having the following composition was dried and the coating weight was 1.8 g / m 2.
² and dried, and wound up in a coil shape. Composition of photosensitive solution 2-hydroxy-3-phenoxypropyl methacrylate / 2-hydroxyethyl methacrylate / methacrylic acid / methyl methacrylate / acrylonitrile = 30 /
20/5/20/25 weight ratio copolymer: 3.0k
g 2-Methoxy-4-hydroxy-5-benzoylbenzenesulfonate of a condensate of 4-diazodiphenylamine and formaldehyde: 0.3 kg Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Industry Co., Ltd.): 0.1 kg Malic acid: 0.03 kg ethylene Glycol monomethyl ether: 11.0
kg N-N'-dimethylformamide: 1.0 kg

Next, as shown in FIG. 2, the upper and lower blades 2, 3 of the two sets of slitters 1 are set at predetermined positions at intervals in the width direction, and the clearance between the upper and lower blades 2, 3 is set to 20 μm. , Width of product B is 398mm
(Unnecessary portions C of both side edges were cut to 31 mm), and at the same time, 560 mm was cut transversely, and thousands of photosensitive lithographic printing plates (PS plates) a were produced while piling (accumulating).

On the other hand, for comparison, a slitter having upper and lower blades set as shown in FIG.
A 560 mm PS plate b was produced.

After exposing the photosensitive layers of the PS plates a and b prepared as described above to an image, using a developer PS-3 for negative PS plate manufactured by Fuji Photo Film Co., Ltd., a dilution ratio with water of 1:
In 1, the developer was developed at a liquid temperature of 25 ° C. for 30 seconds, and then washed with water, and then subjected to a gumming treatment using an aqueous solution of gum arabic of 8 ° Baume.

When these plates were used to print 70,000 newspapers on a newspaper rotary press BHK manufactured by Tokyo Kikai Seisakusho, the printing started on the periphery of the newspaper printed from the PS plate a. No stains were seen until the end of printing. On the other hand, on one side of the periphery of the newspaper printed from the PS plate b, dirt was generated from about 100 copies from the start of printing until the end of printing.

The bending dimension L of the 398 mm side edge of the PS plate a was measured by an electron microscope.
It was about 80 μm. On the other hand, about 3
Burrs of 5 μm were exposed on the upper surface side.

Example 2 First, a coiled aluminum plate (material 1050 according to JIS) having a thickness of 0.3 mm and a width of 920 mm is prepared.
Then, this coiled aluminum plate is subjected to brush polishing, electrolytic polishing, anodizing treatment, and hydrophilizing treatment in the same procedure as in Example 1, washed with water, dried, and then coated with the photosensitive liquid used in Example 1, and dried. It was wound up in a coil shape.

Next, FIG. 5 for explaining the manufacturing method of the present invention.
As shown in FIG. 4, the upper and lower blades 2 and 3 of the four slitters 1 are set at predetermined positions at intervals in the width direction, and the clearance between the upper and lower blades 2 and 3 is 10 μm.
The overlap was set to 2 mm, and cutting was performed while taking two products B having a width of 400 mm.
The photosensitive lithographic printing plates (PS plates) c and d were prepared by cross-cutting to 098.8 mm and piling. In this case,
The unnecessary portion E at the intermediate portion was set to be 20 mm.

The PS plates c and d thus produced were subjected to image exposure and development and desensitization treatment (gumming) in the same manner as in Example 1, and then manufactured by Mitsubishi Heavy Industries, Ltd. When PS plates c and d were simultaneously attached to the printing press using Risopia, a newspaper press, and 70,000 copies were printed, the periphery of the printed newspaper was stained from the start of printing until the end of printing. I couldn't.

When the bending dimension L of the edge of the PS plates c and d on the 400 mm side was measured by an electron microscope,
It was about 100 μm.

The embodiments of the present invention have been described above.
The present invention is not limited to the embodiments described above, and various modifications can be made based on the technical idea of the present invention.

[0043]

As described above, the method for producing a photosensitive lithographic printing aluminum plate according to the present invention comprises the steps of forming a coil-shaped or sheet-shaped wide photosensitive lithographic printing aluminum plate with a slitter having a pair of upper and lower blades. in producing a product by cutting into a predetermined size, the upper blade of the prior SL slitter comprising performs arranged to come outside of the product with respect to the lower blade,
Of the upper blade and the lower blade of the slitter, the lower blade is flat.
Using a countersunk blade with a slightly angled top blade
Since the photosensitive lithographic printing aluminum plate is cut, a lithographic plate suitable for a large number of print copies can be manufactured without burrs on the edges of the product. Therefore, if the lithographic printing plate obtained by the production method of the present invention is mounted on a printing press, even in the case of printing a large number of copies, the peripheral portion of the printed matter will not be stained from the start of printing to the end of printing, and good quality Printed matter can be produced in large quantities.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a method for manufacturing an aluminum plate for photosensitive lithographic printing according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state where an aluminum plate is cut by a slitter used in the manufacturing method.

FIG. 3 is a sectional view showing a product manufactured by the above manufacturing method.

FIG. 4 is an enlarged sectional view showing an edge portion of the product.

FIG. 5 is a sectional view showing a state where an aluminum plate is cut by a slitter used in a manufacturing method according to another embodiment of the present invention.

FIG. 6 is an enlarged sectional view showing a state in which a lower portion of a lip of the product is crushed.

FIG. 7 is a cross-sectional view showing a state in which an aluminum plate is cut by upper and lower blades of a slitter used in a conventional method of manufacturing an aluminum plate for photosensitive lithographic printing.

FIG. 8 is a cross-sectional view showing a state in which the aluminum plate is cut by another combination of upper and lower blades of a slitter used in the conventional method of manufacturing an aluminum plate for photosensitive lithographic printing.

FIG. 9 is a cross-sectional view showing a product manufactured by a conventional method for manufacturing an aluminum plate for photosensitive lithographic printing.

[Explanation of symbols]

 Reference Signs List 1 slitter 2 upper blade 3 lower blade 4 photosensitive layer A aluminum plate B product

Continuation of the front page (56) References JP-A-62-19315 (JP, A) JP-A-7-32758 (JP, A) JP-A-5-104872 (JP, A) JP-B-57-46754 (JP) , B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41N 1/08 G03F 7/09 501 B23D 19/06 B23D 15/06

Claims (2)

(57) [Claims] 1. A slitter having a pair of upper and lower blades,
When manufacturing a product by cutting a coil-shaped or sheet-shaped wide-width photosensitive lithographic printing aluminum plate into a predetermined size,
Of the photosensitive lithographic printing aluminum plate performed by placing the blade on the previous SL slitter to come outside of the product with respect to the lower blade
In the manufacturing method, the upper blade and the lower blade of the slitter
A flat blade is used for the lower blade, and the upper blade is slightly angled.
Aluminum plate for photosensitive lithographic printing using a plate knife
A method for producing an aluminum plate for photosensitive lithographic printing, characterized by cutting an aluminum plate. 2. A gap between the upper blade and the lower blade is cut.
Spread by 2 to 20% of the thickness of the aluminum plate,
Alternatively, the overlap between the upper blade and the lower blade is set to 0.5
請 3.0 mm
Production of the aluminum plate for photosensitive lithographic printing according to claim 1
Method.