JP2602687B2 - Manufacturing method of metal plate for plate material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a metal plate for a plate material excellent in hydrophilicity, water retention, adhesion to ink-philic substances, dot reproducibility and printing durability. Related to manufacturing method.

[Conventional technology]

At present, a lithographic printing metal plate using a metal material includes an aluminum or aluminum alloy plate that can easily obtain a surface shape suitable for lithography by a method of mechanical, electrochemical, or a combination of both. It is commonly used as The thickness of the aluminum or aluminum alloy plate is required to be 0.1 to 0.3 mm in terms of mechanical properties. For example, 0.3mm thick for newspaper printing, 0.1mm for light printing
~ 0.2mm is used.

Meanwhile, to reduce costs and improve mechanical properties,
Development of a PS plate using a steel plate as a substrate in addition to an aluminum or aluminum alloy plate is being studied. For steel plates,
To achieve mechanical strength comparable to a 0.3mm thick aluminum plate
0.1mm is good.

However, in the case of steel sheets, high spot count (hereinafter H
SC), and a surface suitable for PS plates cannot be obtained.
For this reason, chemical etching (Japanese Patent Laid-Open No. 57-143490)
No., JP-A-58-160196, JP-A-61-270380), iron plating (JP-A-57-143490, JP-A-59-48190), electrolytic etching (JP-A-59-142192) Has been performed. Thus, in the case of a steel plate, it was difficult to obtain an inexpensive surface suitable for a PS plate by a mechanical method.

[Problems to be solved by the invention]

In a method of manufacturing a metal plate for a plate material using a steel sheet as a substrate, an inexpensive roughened substrate has not been obtained by a conventional rolling method.

[Means for solving the problem]

Accordingly, an object of the present invention is to provide an inexpensive and mechanical method for providing a surface suitable for a PS plate in a method of manufacturing a metal plate for a plate using a steel sheet as a substrate. Moreover, the surface roughening treatment by the mechanical method of the present invention has no directivity in the surface shape (Ra and HSC), and the number of peaks per single length (HSC) is large. Excellent stability over time, water retention, adhesion to ink-philic substances, dot reproducibility and printing durability.

The gist is that the surface of a steel plate with a thickness of 30 to 250 μm is subjected to finish cold rolling or temper rolling by a liquid honing roll as a surface roughening treatment to obtain a surface roughness Ra.
(JIS B 0601) A method in which a steel sheet of 0.3 to 0.8 μm, HSC 40 to 80 pieces / 2.5 mm is obtained, and then subjected to plating for imparting corrosion resistance or to a chemical conversion treatment after plating, and further to a known hydrophilic treatment.

 Hereinafter, the present invention will be described in detail.

The substrate used for the metal plate for a printing plate of the present invention is a steel plate having a thickness of 30 to 250 μm manufactured by a rolling method. 30μ
If the thickness is less than m, the production cost is high, which is uneconomical. If it exceeds 250 μm, it will be difficult to handle the plate material,
It is uneconomical in terms of material costs. Next, surface roughness Ra (JIS B 0601) 0.3-0.8 μm, which has good hydrophilicity, water retention, adhesion to ink-philic substances, dot reproducibility and printing durability
In order to obtain a surface shape with a small difference between Ra and HSC in the direction parallel and perpendicular to the rolling direction,
Finish cold rolling or temper rolling is performed using a liquid honing roll having a surface roughness Ra of 1.0 to 3.0 μm and a HSC of 40 to 80 pieces / 2.5 mm as a work roll. Ra of less than 0.3μm or H of finish cold rolled or temper rolled steel sheet
If SC is less than 40 pieces / 2.5 mm, the adhesion to the photosensitive material and the water retention are not sufficient, so that the photosensitive material is peeled or stained during printing. Also, the halftone dots of the positive type PS plate need to be smaller than those of the positive manuscript, 40 HSC / 2.
If it is less than 5 mm, the dot reproducibility is poor. On the other hand, if Ra exceeds 0.8 μm, HSC is less than 40 pieces / 2.5 mm in production, which is not preferable. Also, the higher the HSC, the better the water retention, the adhesion to the photosensitive material and the dot reproducibility, but it is difficult to exceed 80 / 2.5 mm in production. In addition, as an abrasive for liquid honing rolls, particle size (JIS R 6001) # 40-150
Of alumina, alumina-zirconia, zirconia, silica or titania is preferred. In particular, alumina of # 60 to # 150 is preferable. The concentration of the abrasive, the air pressure, and the water pressure including the abrasive were such that the Ra of the roll was 1.3 to 3 μm,
Should be adjusted to be 40-80 pieces / 2.5mm. Especially,
Preferably, Ra is 1.3 to 2.1 μm and HSC is 60 to 80 / 2.5 mm. For example, when alumina having a particle size of # 80 is used, a concentration of 125 g /
, Rolls Ra if the water pressure 0.35 kg / cm ² in air pressure 6~10kg / cm ² is 1.3～2.1Myuemu, HSC is 60 to 80 pieces /2.5Mm. This mechanical roughening method has the advantage that both sides can be performed simultaneously.

Next, simply performing finish cold rolling or ultra-high quality rolling on the steel sheet using the liquid honing roll as a work roll is inferior in corrosion resistance, generates red rust, and is not preferable. As the surface treatment, a single plating of zinc, nickel, tin, copper or chromium having a rust-preventing effect on a steel sheet, a plurality of platings combining two or more of these metals, or one or two of these metals The alloy plating including the above is applied. Such surface treatment not only improves the corrosion resistance but also effectively acts on the adhesion to the ink-philic substance forming the image area. In the case of plating, in particular, it is effective for roughening the surface by appropriate growth of electrodeposition nuclei. For this reason, it is better to perform the surface treatment under a condition that makes the surface uneven, rather than a smooth plating condition. It is economical to set the plating thickness so that the corrosion resistance of the steel sheet is guaranteed as the lower limit. In the case of chromium plating, 1 to 20 mg / dm ²
In the case of other single plating, multiple plating or alloy plating, 1 to 40 g / m ² is preferable. In addition, by performing a known chemical conversion treatment for imparting corrosion resistance after plating, not only corrosion resistance but also adhesion to a photosensitive agent is further improved. Known chemical conversion treatments include, for example, immersion in a solution containing chromate, dichromate, phosphate, molybdate, silicate, borate, perborate, aluminate, etc. This is an electrolytic treatment. In particular, after tin plating or galvanizing, in a solution containing dichromate such as chromic anhydride, potassium dichromate or sodium dichromate, or in a solution containing chromic anhydride and sulfuric acid, the chromium content is reduced to 0.
When 05~0.3mg / dm ² is deposited, it is also improved dot reproducibility as well corrosion resistance.

Among the surface-treated metals having the above-mentioned surface roughness, there are those which show hydrophilicity and can be used as a plate material as they are, but many surface-treated metal plates have insufficient hydrophilicity, and Since the deterioration with time of the hydrophilic property is remarkable, the hydrophilic treatment is performed again. The hydrophilic treatment may be a known treatment generally used, for example, silicate treatment, organic titanium compound treatment, organic phosphoric acid treatment, ferrocyanide ferricyanide treatment, organic polymer coating treatment such as polyacrylic acid or carboxymethyl cellulose, The treatment includes a treatment with a metal compound sol or a treatment with a water-soluble zirconium salt, and is not limited.

[Action]

The surface of the rolling roll is subjected to liquid honing to increase the HSC, and a finish plate having a higher HSC than the shot blast method can be obtained by finish cold rolling or temper rolling. HSC
Is high, the surface area per single area is large. Therefore, the amount of water retention is large, and the adhesion to the photosensitive material is improved by the anchor effect. Furthermore, because the surface is whitened,
Higher UV reflectance, improved halftone dot reproducibility, PS
An optimal substrate is obtained as a plate support.

〔Example〕

 The present invention will be specifically described with reference to examples.

Example 1 A steel plate having a thickness of 151 μm was coated with alumina having a particle size of # 80 (product name: AB
RAX, manufactured by Nippon Abrasives Co., Ltd.) Temper rolling using liquid honing roll (Ra1.7μm, HSC70 pieces / 2.5mm), roughening to 150μm, Ra0.4μm, HSC65 pieces / 2.5mm did. Using a solution containing 250 g / zinc sulfate and 30 g / ammonium sulfate, zinc was plated at 5 g / m ² at a temperature of 50 ° C. and a current density of 20 A / dm ² . Then, in a solution containing 5 g of potassium zirconium fluoride and 2 g of trisodium phosphate, at a temperature of 40 ° C. and a current density of 0.5 A / dm ² , the steel sheet is treated as a cathode for 4 seconds, washed with water and dried. Thus, a metal plate for a plate material was obtained.

Example 2 A 121 μm-thick steel sheet was coated with alumina having a particle size of # 46 (product name: AB
RAX, manufactured by Nippon Abrasives Co., Ltd.) Temper rolling using a liquid honing roll (Ra 2.3 μm, HSC 56 pieces / 2.5 mm) to roughen to a sheet thickness of 120 μm, Ra 0.55 μm, HSC 47 pieces / 2.5 mm did. Using a solution containing 240 g / zinc chloride and 290 g / ammonium chloride, zinc was plated at 3 g / m ² at a temperature of 55 ° C. and a current density of 30 A / dm ² . Then chromic anhydride 30g /
The solution was immersed in a solution of 1 g / sulfuric acid at a temperature of 30 ° C., and the chromium compound was attached in an amount of 0.3 mg / dm ² in terms of chromium. Furthermore, in a solution containing 5 g / potassium zirconium fluoride, at a temperature of 30 ° C., at a current density of 1 A / dm ² , a steel sheet is treated as a cathode for 2 seconds, washed with water, dried, and dried. A metal plate was obtained.

Example 3 Alumina having a grain size of # 120 (product name: A
Temper rolling using rolls (Ra1.3μm, 80 HSC / 2.5mm) liquid honed with BRAX (Nippon Abrasives Industries)
The surface was roughened to a thickness of 245 μm, Ra 0.3 μm, and 80 HSCs / 2.5 mm. Using a solution containing 250 g / chromic anhydride and 2.5 g / sulfuric acid, 1 mg / dm ^{2 of} chromium was plated at a temperature of 50 ° C. and a current density of 40 A / dm ² . Next, alumina sol (product name:
In a solution containing AS-200, Nissan Chemical Co., 20 g /, silica sol (product name: Snowtex-0, Nissan Chemical Co., Ltd.) 1 g /
At a temperature of 20 ° C. and a current density of 0.2 A / dm ² , the steel plate was treated as a cathode for 25 seconds, washed with water and dried to obtain a metal plate for a printing plate.

Example 4 A zirconia particle size of # 40 (product name: P
Temper rolling using rolls (Ra3.0μm, HSC44 / 2.5mm) liquid honed with C-Z, manufactured by Nippon Abrasives Co., Ltd.
The surface was roughened to a thickness of 77 μm, Ra 0.8 μm, and 41 HSCs / 2.5 mm. Using a ferrostan bath (80 g of stannous sulfate, 80 g of phenolsulfonic acid, 20 g of 1 bean EN), temperature
Tin was plated at 3 g / m ^{2 under} the conditions of 45 ° C. and current density of 7 A / dm ² .
Next, in a solution containing 30 g / sodium dichromate, the steel plate was treated as an anode for 2 seconds at a temperature of 45 ° C. and a current density of 10 A / dm ² . Furthermore, potassium zirconium fluoride
It was immersed in a solution containing 20 g / at a temperature of 70 ° C. for 60 seconds, washed with water and dried to obtain a metal plate for a printing plate.

Example 5 Rolls (Ra2.7 μm, HSC50 / 2.5) of a steel plate having a thickness of 200 μm, which were liquid-honed with an alumina-zirconia abrasive having a grain size of # 54 (product name: ABRAX-Z73, manufactured by Nippon Abrasives Industries)
mm), temper rolling with a thickness of 198μm, Ra0.7μm, HSC44
The pieces were roughened to 2.5 mm. To this, stannous chloride 250g /,
Nickel chloride 50g /, sodium fluoride 20g /, hydrochloric acid 10
Using a bath containing g / g, a nickel-tin alloy was plated at 40 g / m ² at a temperature of 60 ° C. and a current density of 5 A / dm ² . Then, it was immersed in a solution containing 10 g / of zirconium sol (product name: Cataloid-Zr-2, manufactured by Catalyst Chemical Industry) at a temperature of 60 ° C. for 60 seconds, washed with water and dried to obtain a metal plate for a plate material. Obtained.

Example 6 Using a roll (Ra2.5 μm, 50 HSC / 2.5 mm) liquid honing a 30 μm-thick steel plate with a titania-type abrasive having a grain size of # 150 (product name: PC-T, manufactured by Nippon Abrasives). After temper rolling, it was roughened to a plate thickness of 29 μm, Ra of 0.6 μm, and 48 HSCs / 2.5 mm. Using a Watt bath (nickel sulfate 240 g / nickel chloride 45 g / boric acid 30 g /), nickel was plated at 20 g / m ² at a temperature of 50 ° C. and a current density of 5 A / dm ² . Then, zinc sulfate 250 g /, using a solution containing ammonium sulfate 30 g /, a current density of 5A / dm ² conditions zinc at 20 g / m ²
Plated. Further, a known hydrophilic treatment (gum arabic is added to 0.1 g).
5 μm and dried) to obtain a plate metal plate.

Comparative Example 1 Rolls (Ra1.7 μm, HSC20) processed by the shot blast method using the same steel plate having a thickness of 250 μm as in Example 3.
Temper rolling at 2.5mm), 245μm, Ra0.4μm, HSC18
Individual / 2.5mm steel plates were obtained. This was subjected to the same chromium plating and hydrophilic treatment as in Example 3, washed with water and dried.

The following various tests were performed using the plate metal plate thus obtained.

<Surface Roughness> The surface roughness was measured using a stylus-type profilometer (name: SURF-1A, manufactured by Tokyo Seimitsu Co., Ltd.).
Count, a measurement length of 2.5 mm was extracted from the cross-sectional curve, and the number of peaks when the peaks and valleys were distinguished based on whether or not they were above the average line) was measured.

<Hydrophilic> hydrophilicity, immediately after preparation of the plate material for the metal plate, positive type photosensitive solution: applying as (product name Quick wipe on positive type, Ueno Chemical Co., Ltd.) coating weight after drying is 2.0 g / m ² Then, a positive original film is adhered to the surface and exposed for 70 seconds from a distance of 1m using a 2kw metal halide lamp (New Idol Fin 2000 manufactured by Iwasaki Electric Co., Ltd.) as a light source, and a developer (Fuji Photo Film Co., Ltd.) Immediately after forming an image by dipping in DP-3) manufactured by Sharp Corporation at a temperature of 25 ° C. for 45 seconds, or after the plate was further aged for one week, each wet area was measured.

The measurement conditions of the wet area were such that 0.1 cc of water was dropped on the non-image portion on the plate metal plate or plate obtained under the above two conditions, and the average diameter of the wet diameter was determined. The average diameter of the wet size is 10
If it is less than mm, it was marked with x, if it was 11 to 25 mm, it was marked with △, and if it was more than 25 mm, it was marked with ○.

<Dot Reproducibility> The dot reproducibility was measured by magnifying the halftone dots (positive manuscript 48.9% halftone dots, 150 lines) of the plate prepared in the hydrophilicity evaluation 50 times and measuring the halftone dot area. The evaluation was made based on the difference from the positive original, that is, the value obtained by the following equation.

If the value is 5 or more, mark ○, if it is 3 to 5, mark △, and mark 3 or less ×
Marked.

<Adhesion to photosensitive material> The adhesion to the photosensitive material was measured by applying the plate prepared in the hydrophilicity evaluation to an ultra plate cleaner (ABC Chemical) at a temperature of 25.
After immersion for 1 minute under the condition of ° C., it was washed with water, and the degree of peeling of the photosensitive material was visually determined. The symbol “○” indicates that the photosensitive material was not peeled, the symbol “△” indicates partial peeling, and the symbol “×” indicates that the photosensitive material was entirely peeled.

<Printing durability> The printing durability was evaluated by offset printing the plate prepared in the evaluation of hydrophilicity and printing up to 50,000 sheets.

The evaluation results are shown in Table 1. As shown in Table 1, the metal plates for plates according to the present invention of Examples 1 to 6 In comparison with Comparative Example 1 in which temper rolling was performed using a roll processed by the roller method, in terms of dot reproducibility, adhesion to a photosensitive material, and printing durability. The printing durability was 5 for Examples 1 to 6.
No abnormalities were observed after printing 10,000 sheets, but the image peeled off in 10,000 sheets in Comparative Example 1.

〔The invention's effect〕

The method for producing a metal plate for a plate material of the present invention is characterized by a surface roughening treatment method using a liquid honing method, and has a high HSC, hydrophilic stability over time, water retention, adhesion to a photosensitive material and resistance. This method is excellent in printability and is suitable for producing an economical metal plate for a printing plate.

Continuation of the front page (56) References JP-A-59-89787 (JP, A) JP-A-59-67050 (JP, A)

Claims (1)

(57) [Claims] 1. A surface of a rolled steel foil or a steel plate having a thickness of 30 to 250 μm, a surface roughness Ra of 1.3 to 3.0 μm and HSC of 40 to 80 pieces / 2.
5mm liquid honing roll is used as a work roll, finish cold rolling or temper rolling is performed, Ra of rolled steel foil or steel sheet is 0.3 to 0.8μm, HSC is 40 to 80 pieces / 2.5mm
Then, any one of the following surface treatments A to D: A: Zinc, nickel, tin, copper or chromium alone plating, B: Zinc, nickel, tin, copper or chromium Layer plating, C: Zinc, nickel, tin, copper or alloy plating containing one or more of chromium, D: After plating of A, B or C, chromate, dichromate, phosphoric acid A method for producing a metal plate for a plate material, comprising using a material subjected to a chemical conversion treatment with a salt, molybdate, silicate, borate, perborate or aluminate.