JPH07191453A - Production of photosensitive planographic printing plate and base therefor - Google Patents

Abstract

PURPOSE:To provide a method for producing a photosensitive planographic printing plate and a base therefor which can improve added value while a design on a part of the surface provided with the photosensitive resin layer of the base made of aluminum is realized, and has no adverse influence upon a photosensitive resin layer and high design quality thereof is kept. CONSTITUTION:An aluminium plate is subjected to a cleaning treatment by degreasing and etching, then an electrolytic aqueous solution 2 is prepared so as to have prescribed concentrations of nitric acid and aluminium ion and the aluminium plate 7 is arranged in an electrolytic treating cell 5 so that the surface thereof and an electrode 6 are disposed to face each other. A masking plate 8 composed of an insulating material plate in which a design shape is punched is adhered to and covers the surface of the aluminium plate 7. A carbon plate is used as the electrode 6 and the electrolytic aqueous solution 2 is supplied from a nozzle 9 toward the masking plate 8. The electrode 6 and the aluminium plate 7 are connected with a power source 11. In such a manner, an electrochemical surface roughening of the design on the aluminium plate 7 is performed. Then, a photosensitive resin layer is provided on the surface on which roughening of the design is performed.

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 a photosensitive lithographic printing plate and its support, and more specifically, for a photosensitive lithographic printing plate, a roughening treatment for coating a photosensitive resin layer. Of a photosensitive lithographic printing plate and its support, in which a rough surface (for example, a design) having an arbitrary shape is realized on the surface by electrochemically roughening a part of the surface (surface) to be subjected to The present invention relates to a manufacturing method.

[0002]

2. Description of the Related Art A photosensitive lithographic printing plate mainly comprises an aluminum plate or its alloy plate (which is simply referred to as an aluminum plate) as a support and a photosensitive resin layer, and the support and the photosensitive resin layer. In order to improve the adhesion and to impart water retention to the non-image area, a so-called graining treatment has been conventionally performed to roughen the entire surface of the support to which the photosensitive resin layer is adhered.

As a concrete means of this graining treatment method, sand blast, ball grain, nylon brush and abrasive / brush grain with water slurry, abrasive /
There are a mechanical graining method such as honing grain in which a water slurry is sprayed on the surface of a support at high pressure, and a chemical graining method in which the surface is roughened with an etching agent composed of an alkali, an acid or a mixture thereof. Further, JP-A-52-58602, JP-A-52-152302, JP-A-54-85802, JP-A-55-158298, JP-A-58-120531, and JP-A-60-147394,
JP-A-56-28898, JP-A-60-190392,
JP-A-1-55589, JP-A-1-280590, JP-A-1-118489, JP-A-1-141094, JP-A-1
-148592, JP-A-1-178496, JP-A-1-
188395, JP-A-1-154977, JP-A-2-2
35794, JP-A-3-260100, JP-A-3-25
3600, etc., or the electrochemical method using an AC power supply having a sinusoidal waveform described in JP-A-48-28123 or British Patent No. 896,563. Graining method, an electrochemical graining method using a special waveform described in JP-A-52-58602, and further, for example, JP-A-54-123204 and JP-A-54-63902. A method combining a mechanical graining method and an electrochemical graining method described in JP-A-56-5526.
There is also known a method in which the mechanical graining method described in Japanese Patent No. 1 and the chemical graining method using a saturated aqueous solution of an aluminum salt of a mineral acid are combined.

Among the various roughening treatment methods as described above, as a method for easily controlling the roughened shape, obtaining a fine rough surface, and having a simple structure in terms of equipment, Electrochemical surface roughening treatment can be mentioned.

Since the roughened aluminum surface is soft and easily worn as it is, an anodizing treatment is performed to form an oxide film on which a photosensitive resin layer is provided. The surface of the aluminum plate treated in this manner is hard and has excellent abrasion resistance, and exhibits good hydrophilicity, water retention and adhesion to the photosensitive resin layer.

[0006] Further, surface treatment methods for aluminum building materials, name plates, etc. are widely known. As a concrete means of this treatment method, Japanese Patent Publication No. 60-15
No. 717, a treatment method of electrolytically treating in a smut removing solution to form a pattern on the surface of aluminum, and roughening of aluminum (mechanical, chemical) described in Japanese Patent Publication No. 60-11118. (Electrochemically or electrochemically) processing, AC electrolysis is carried out in an electrolytic bath, and a treatment method of forming a film having a vertical stripe pattern by the action of bubbles generated is disclosed in JP-B-61-54120. For example, aluminium), such as a nameplate made of a plate, is coated with a resin solution in a pattern such as letters and dried to form a protective film, and then electrolytically polished in an electrolytic bath.
A treatment method of removing the protective film to form a pattern such as characters,
After the processing of aluminum (degreasing, mechanical and chemical polishing, hairline and sandblasting, etc.) described in Japanese Examined Patent Publication No. 2-3718, an alumite treatment is applied, and after drying, a printing ink excellent in non-conductivity. A printing method, then dry-cure this by baking processing means, and form a letter, pattern, etc. by electrodeposition coating these surface-treated surfaces, JP-A-59-501.
No. 98, a pattern-forming substance (oil dye or the like) in which a powdery magnetic substance is mixed and dispersed in advance is supplied onto the surface of a water bath liquid, and then the magnetic force generated by an electromagnet is applied to the magnetic substance in the pattern-forming substance. A certain pattern is made to appear on the pattern-forming substance on the liquid by subjecting it to pretreatment (degreasing cleaning, etching, smut removal, etc.) and then anodizing (which may include coloring) treatment. There is a treatment method in which a pattern is formed by adhering it to the formed aluminum material.

Further, a surface treatment method for metals other than aluminum is also widely known. As a concrete means of this treatment method, for example, in the case of copper, Japanese Patent Publication No. 60-4
After pretreatment (electrolytic film formation, electrochemical film formation, chemical treatment, dipping treatment) of the copper plate described in Japanese Patent No. 1154, characters or the like are marked with a marking material having adhesiveness to the copper plate, and other than that. However, a resist film that adheres to the copper plate but does not adhere to the marking material is formed, and then only the marking material is removed, the traces are plated, and then the resist film is removed. In the case of stainless steel, an acid resistant ink is printed on the non-patterned portion of the stainless steel product by screen printing described in JP-A No. 50-56334 and then etched. After corroding the pattern part to form a recess, the bottom of this recess is electrolytically polished to a state in which an acid-resistant liquid is applied to a place other than the recess,
This stainless steel product is used as an anode and is plated with gold, silver, copper or the like as a cathode, and a metal plating layer of gold, silver, copper or the like is formed on the bottom of the recessed portion, JP-B-53-39869.
Japanese Patent Publication No. 56-10999 and Japanese Patent Publication No. 56-10999, a method of forming a colored pattern on a stainless clad aluminum plate, and a mechanical treatment on the back surface of a stainless steel plate described in Japanese Patent Laid-Open No. 2-307629. After patterning (scribing, pressing a jig with a pattern, drawing a pattern with a sharp knife, embossing, etc.),
There is a treatment method such as a coloring process (coloring in a sulfuric acid-chromic acid solution, curing of an oxide film).

On the other hand, the entire back surface of the photosensitive lithographic printing plate which is not provided with the photosensitive resin layer may be surface-treated.
As a concrete means of this processing method, Japanese Patent Laid-Open No. 3-90
No. 388, a method of treating with an alkali metal silicate aqueous solution, a coating having a surface-roughening agent dispersed therein, which is described in JP-A-62-1586, is applied,
A method of mechanically treating with a ball grain, a honing grain, a brush grain or the like, or a method of directly powdering the powder, and the resin particles described in JP-A-3-249652 are dispersed almost uniformly. Then, a method of heat-sealing or a method of forming an embossed pattern on the whole by pressing an embossing roll from the back surface described in JP-B-55-237 is known. Further, in a photosensitive lithographic printing plate, an inkjet method, a printing method, etc. have been devised as a method for embodying a design on a part of the back surface of the support.

However, these methods are not only disadvantageous in that they adhere to the photosensitive resin layer when they are wound up or piled up, because the ink portion adhered by printing rises, and the ink melts during development. It has a drawback of calling out. Furthermore, curing (UV or heat)
If a mold ink is used to prevent elution at the time of development, there is a disadvantage in that the equipment cost is enormous. Further, there is a method of pressing a roll or plate embodying the design with the back surface of the support of the photosensitive lithographic printing plate, but this method is not only a drawback that the design part of the roll or plate is worn but also the support When the photosensitive resin layer is provided, the flatness of the support is impaired and the uniformity of the coating film cannot be obtained when the photosensitive resin layer is provided.

As a method for solving these problems, Japanese Patent Application No. 5-100118 discloses that a surface (back surface) of a support for a photosensitive lithographic printing plate on which a photosensitive resin layer is not provided is desired. By covering the back surface of the support with an insulating material plate whose shape has been punched out and applying an alternating current to the back surface of the support through the punching surface of the insulating material plate, a rough surface of any desired shape can be formed on the back surface of the support. A method for producing a photosensitive lithographic printing plate and a support for the surface treatment is disclosed in Japanese Patent Application No. 5-1938.
No. 97, the surface of a cylindrical drum is provided with an insulating material plate having a desired arbitrary shape punched out, an electrode is provided inside the drum, and the drum is wrapped with an aqueous electrolyte solution on the drum. Continuous processing methods and devices have been proposed in which an alternating current is applied to the support.

[0011]

SUMMARY OF THE INVENTION However, these methods are directed to a photosensitive lithographic printing plate in which a design is embodied on a part of the surface (back surface) of the aluminum support on which the photosensitive resin layer is not provided, and the support thereof. The present invention does not embody a design on a part of the surface of the aluminum support on which the photosensitive resin layer is provided.

An object of the present invention is to embody a design on a part of the surface of the aluminum support on which the photosensitive resin layer is provided, the design not adversely affecting the photosensitive resin layer, and the development treatment is completed. Another object of the present invention is to provide a method for producing a photosensitive lithographic printing plate and its support, which retains its high designability and improves added value.

[0013]

The above object of the present invention is to provide a photosensitive lithographic printing plate in which a photosensitive resin layer is provided on an aluminum support, and to have a desired arbitrary shape on the surface on which the photosensitive resin is provided. A photosensitive lithographic printing plate characterized by having a rough surface. In a method for producing a photosensitive lithographic printing plate support having an aluminum plate as a support, a part of a surface of the support on which a photosensitive resin layer is provided is covered with an insulating material plate having a desired arbitrary shape punched out. And applying a current to the support through a punching surface of an insulating material plate in an electrolytic aqueous solution to roughen the surface of the support on which the photosensitive resin is provided in a desired arbitrary shape. A method for producing a photosensitive lithographic printing plate support. After the surface roughening of the surface of the support on which the photosensitive resin layer is provided, the entire surface is electrochemically roughened, and the photosensitive lithographic printing plate described above. Method for producing plate support. Achieved by

The present invention will be described in detail below.
The aluminum plate used in the present invention is JIS A
1050 materials, JISA1100 materials, JISA3003
Materials, JIS A3103 materials, JIS A5005 materials, and various other aluminum plates can be used, but even if the design is embodied on a part of the surface (surface) that is in close contact with the photosensitive resin layer, the surface functions as a printing plate. Will affect
In the case of uniform aluminum on the front and back, when selecting the material, the surface that is in close contact with the photosensitive resin layer generally has priority, and the most suitable one is selected according to the surface treatment (mechanical, chemical, electrochemical) method. There is a need to. However, in the case of an aluminum plate in which the front surface and the back surface are composed of different components, the present invention is not limited to this, and the optimum one can be selected according to the processing method of each surface (front surface, back surface). However, this is not limited to the case of an aluminum plate whose front surface and back surface are composed of different components, and each surface (front surface,
The most suitable one can be selected according to the processing method on the back side).

The surface of the aluminum plate that comes into close contact with the photosensitive resin layer (surface) is electrochemically roughened for embodying the design of the present invention and electrochemical for ensuring performance as a printing plate. To remove the rolling oil on the front and back surfaces as necessary, or to increase the surface area of the surface before the surface roughening treatment is performed, or in order to expose a clean aluminum surface. Mechanical graining treatment may be performed. For the pretreatment for removing the rolling oil on the front and back surfaces, an organic solvent such as trichlene, a surfactant, or sodium silicate is used, and in order to expose a clean aluminum surface, a hydroxide is used. Alkaline etching agents such as sodium and potassium hydroxide are widely used. A ball grain method, a nylon brush method or the like is widely used for mechanical graining for increasing the surface area of the surface.

In the electrochemical graining for securing the performance of the printing plate following the electrochemical graining of the present invention, the surface (surface) that is in close contact with the photosensitive resin layer is carried out as necessary. However, the surface treatment of the present invention for embodying the design is
An AC power supply waveform is used, and in addition to a sine wave three-phase AC, an alternating waveform such as a rectangular wave or a trapezoidal wave is also included. When an electrochemical graining treatment of the surface (surface) for adhering to the photosensitive resin layer and ensuring the performance as a printing plate is performed, before or after the treatment of the present invention is performed. Either method is possible, but it is preferable to carry out after the treatment of the present invention. It is also possible to start the pretreatment and / or the mechanical graining treatment and perform the electrochemical graining treatment for ensuring the performance as a printing plate and the electrochemical graining treatment of the present invention separately. Although possible, continuous operation is preferred.

The present invention relates to electrochemical roughening for embodying a design on the surface on which the photosensitive resin layer is provided, and henceforth, the description will be focused on the surface on which the photosensitive resin layer is provided. To do. In the present invention, a part of the surface of the support on which the photosensitive resin is provided is covered with an insulating material plate in which a desired arbitrary shape is punched out, and the support is passed through the punching surface of the insulating material plate in an aqueous electrolyte solution and a current is applied. The insulating material in this case refers to a material plate having an insulating or insulating structure. As the electrolyte aqueous solution, an acidic aqueous solution containing hydrochloric acid, nitric acid, hydrofluoric acid, boric acid, or tartaric acid as an essential component, or an acidic aqueous solution composed of a mixture of two or more of these acids is suitable, and contains hydrochloric acid or nitric acid as a main component. Solutions are preferred. As the electrolyte aqueous solution, conventionally known ones can be used. And its concentration is appropriately selected from the range of about 0.5% by weight to 5.0% by weight. Corrosion inhibitors (or stabilizers) such as nitrates, monoamines, diamines, aldehydes, phosphoric acid, chromic acid, boric acid, ammonium salts, aluminum salts, carbonates, etc. may be added to these electrolyte aqueous solutions as necessary.
Can be added. In the present invention, as described in US Pat. No. 4,087,341,
It is disclosed in Japanese Patent Publication No. 61-48596, which is a method of passing an alternating current through an aluminum plate in an aqueous nitric acid electrolyte solution so that the quantity of electricity at the anode (QA) becomes larger than the quantity of electricity at the cathode (QC). A circuit for the auxiliary counter electrode for connecting the circuit for the auxiliary counter electrode in parallel to the circuit connected to the main counter electrode for the aluminum plate, and for forming a diode or a diode-like mechanism for controlling the flow of the anode current in the main counter electrode. A method using the electrochemical surface roughening treatment apparatus provided in the above may be applied. The voltage applied to the aluminum plate is preferably about 1V to about 50V.
V, more preferably 2 V to 30 V, the current density is preferably about 3 A / dm ² to about 300 A / dm ² , more preferably 3 A / dm ^{2 to} 250 A / dm ² , and the electric quantity is preferably about ⁵ C. / dm ² ~ about 500C / dm ^2, more preferably selected from the range of ^{5C / dm 2 ~300C / dm 2} . The temperature of the aqueous electrolyte solution is preferably about 10 ° C to 70 ° C, more preferably 20 ° C to 60 ° C. The surface thus electrochemically roughened is
Then, a light etching process is performed. The surface roughness (Ra) is preferably about 0.2 μm to
The thickness is more preferably 0.7 μm, and more preferably 0.25 μm to 0.5 μm.

However, usually, the surface (surface) that is in close contact with the photosensitive resin layer is subjected to an etching treatment after the electrochemical graining treatment. When the etching treatment as described above is performed subsequently to the surface treatment for embodying the design, it is possible to perform them separately, but it is preferable to perform them simultaneously. The etching treatment is to dissolve the surface of the aluminum plate with an aqueous solution of acid or alkali. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid,
Nitric acid, hydrochloric acid, etc. are included, and the alkali includes sodium hydroxide, potassium hydroxide, sodium triphosphate, potassium triphosphate, sodium aluminate, sodium silicate, sodium carbonate and the like. Among these, it is particularly preferable to use the latter aqueous solution because the etching rate is faster. Depending on the performance of the printing plate, the etching treatment and the desmut treatment subsequent to the electrochemical treatment for embodying the design are omitted, and the electrochemical treatment for providing the next photosensitive resin layer is continuously performed. Sometimes. This desmutting treatment is for removing the generated smut and ensuring the uniformity of graining in the electrochemical treatment that is subsequently performed to provide the photosensitive resin layer. Next, an electrochemical treatment is performed on the entire surface so as to adhere to the photosensitive resin layer to ensure the performance as a printing plate, followed by an etching treatment and a desmut treatment for removing the generated smut. Since the details of the method have been described above, the description thereof will be omitted.

The surface of the aluminum plate treated as described above is soft and easily worn as it is, as described above. Therefore, it is desirable to form an anodized film in order to improve its strength. The anodizing treatment can be performed according to a conventionally known method. For example, sulfuric acid, phosphoric acid, oxalic acid, chromic acid, amidosulfonic acid or a mixture of two or more thereof, or an aqueous solution or non-aqueous solution containing aluminum ions in them is used as an electrolyte aqueous solution, and anodizing treatment is mainly performed using direct current. However, alternating current or a combination of these currents can also be used. The electrolyte concentration is 1% to 80% by weight, the temperature is in the range of 5 ° C to 70 ° C, and the amount of anodized film is 0.1 g / m ^2.
The range of up to 4.0 g / m ² is preferred.

The surface treatment (for example, hydrophilic treatment) necessary for the surface of the photosensitive lithographic printing plate support thus obtained.
Further, a conventionally known photosensitive resin layer is provided, and a photosensitive lithographic printing plate having a design embodied on the back surface thereof can be obtained.

[0021]

EXAMPLES The present invention will be described in more detail below with reference to examples. In addition, "%" in the examples means "% by weight" unless otherwise specified. (Example-1) An aluminum plate having a thickness of 0.24 mm (2
40mm x 120mm, JISA1050 material) 10%
After immersion in an aqueous solution of sodium hydroxide at 50 ° C. for 20 seconds to perform cleaning treatment by degreasing and etching, it was washed with water, then neutralized with a 25% aqueous sulfuric acid solution for 30 seconds and washed with water. Next, the aqueous electrolyte solution 2 was adjusted so that the nitric acid concentration was 10 g / 1 and the aluminum ion concentration was 7 g / 1.
Was prepared, charged into a stock tank 3 of an electrolytic treatment apparatus 1 as shown in FIG. 1, and fed at a temperature of 55 ° C. to a electrolytic treatment tank 5 via a pump 4. The aluminum plate 7 is immersed in the electrolytic treatment tank 5 so as to face the electrode 6, and the aluminum plate 7 is immersed in an electrolytic aqueous solution for 15
It was arranged to face each other with a space of mm. This time,
A masking plate 8 (260 mm × 140 mm) having a thickness of 1 mm and made of an insulating material plate punched with an arbitrary shape as shown in FIG. 2 was closely adhered to and covered the back surface of the aluminum plate 7. The electrode 6 has a thickness of 50 mm (240 mm).
A carbon plate of (× 120 mm) was used. Further, the aqueous electrolyte solution 2 was supplied toward the masking plate 8 from the blowing nozzle 9 at a flow rate of 50 m / min. The electrode 6 and the aluminum plate 7 are connected to a power source 11 by a cable 10. In such a state, a sinusoidal alternating current having a frequency of 60 Hz and a current density of 20 A / dm ^{2 was} supplied from the power source 11 for 3 seconds to electrochemically roughen the aluminum plate 7, remove the aluminum plate 7, and remove the temperature. It was immersed in a 25% sulfuric acid aqueous solution at a temperature of 60 ° C. for 40 seconds to desmut, and washed with water.
Next, the masking plate 8 is removed, the aluminum plate 7 subjected to the electrochemical treatment is set so that the treated surface is electrolyzed, and the frequency 6 is applied from the power source 11 to the treated surface.
6. Trapezoidal waveform alternating current of 0 Hz and current density of 25 A / dm ²
After being supplied for 2 seconds, the entire surface of the aluminum plate 7 was electrochemically roughened. After that, the roughened aluminum plate 7 is washed with water and immersed in a 25% sulfuric acid aqueous solution at a temperature of 60 ° C. for 40 seconds (desmut treatment). / M ² was anodized. Finally, it was washed with water and dried to obtain a photosensitive lithographic printing plate support in which an arbitrary design was embodied by electrochemical roughening on a part of the surface on which the photosensitive resin layer was provided. The presence of the design embodied on the surface of the photosensitive lithographic printing plate support provided with the photosensitive resin layer can be recognized. The degree of roughening of that portion was Ra = 0.30 μm to 0.35 μm, which was almost the same as the portion without the design.

(Embodiment 2) The same processing as in Embodiment 1 was carried out except that the supply time of the sinusoidal waveform AC in Embodiment 1 was set to 5 seconds. As a result, the embodied design portion became a little more conspicuous than in Example-1, and the degree of roughening of that portion was Ra = 0.35 μm to 0.40 μm.

Example 3 The same treatment as in Example 1 was carried out except that the electrolyte aqueous solution 2 in Example 1 had a hydrochloric acid concentration of 11.5 g / 1 and an aluminum ion concentration of 4.5 g / 1. . As a result, the embodied design portion was the same as in Example-1.

(Comparative Example-1) The same processing as in Example-1 was carried out except that the supply time of the sinusoidal waveform AC in Example-1 was set to 1 second. As a result, in the embodied design portion, the recognition of the design was considerably difficult as compared with Example-1, but the degree of roughening of that portion was Ra = 0.30.
The thickness was in the range of μm to 0.35 μm, which was almost the same as the portion without the design.

[0025]

The photosensitive lithographic printing plate using the support obtained by the method of the present invention has a desired arbitrary shape embodied on a part of the surface of the support on which the photosensitive resin layer is provided. The rough surface does not adversely affect the photosensitive resin layer, and the high designability is maintained even after the development processing is completed, and the added value can be improved.

[Brief description of drawings]

FIG. 1 is a schematic side view of an electrolytic treatment apparatus of an embodiment of an electrochemical graining treatment method of the method for producing a photosensitive lithographic printing plate support of the present invention.

FIG. 2 is a perspective view of an example of a masking plate used in the electrochemical surface-roughening treatment method of the method for producing a photosensitive lithographic printing plate support of the present invention.

[Explanation of symbols]

 1 Electrolytic treatment device 2 Electrolyte solution 3 Stock tank 4 Pump 5 Electrolysis treatment tank 6 Electrode 7 Aluminum plate 8 Masking plate 9 Nozzle 10 Cable 11 Power supply 12 Electrolyte discharge port

Claims (3)

[Claims] 1. A photosensitive lithographic printing plate having a photosensitive resin layer provided on an aluminum support, wherein the surface provided with the photosensitive resin has a rough surface of any desired shape. Printed version. 2. A method for producing a photosensitive lithographic printing plate support using an aluminum plate as a support, wherein an insulating material having a desired arbitrary shape punched out from a part of a surface of the support on which a photosensitive resin layer is provided. Of a desired arbitrary shape on the surface of the support on which the photosensitive resin is provided by applying a current to the support in the electrolytic solution through the punching surface of the insulating material plate. A method for producing a support for a photosensitive lithographic printing plate, which is characterized by carrying out. 3. The surface of the support, on which the photosensitive resin layer is provided, is roughened electrochemically, and then the entire surface is electrochemically roughened. 2. The method for producing a photosensitive lithographic printing plate support as described in 2.