JPS6119029B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a photosensitive lithographic printing plate (also called a pre-sensitized plate and abbreviated as a PS plate), and particularly relates to a method for producing a photosensitive lithographic printing plate (also called a pre-sensitized plate and abbreviated as a PS plate). The present invention relates to an improved method for producing a photosensitive lithographic printing plate, which comprises directly coating a silver halide emulsion on a plate and drying it. U.S. Patent No. 3511661, Japanese Patent Application Publication No. 1983-27804
OLS No. 2,517,711 and OLS No. 2,640,763 disclose that, in order, conventional materials such as diazo compounds and photopolymers are deposited on a support having a hydrophilic surface such as an aluminum plate. Than
The ultraviolet-sensitive layer used in the photosensitive layer of PS plates,
and a photosensitive lithographic printing plate provided with a silver halide emulsion. However, the UV-sensitive layer
Since it is water-repellent rather than hydrophobic, it has the disadvantage that even if a silver halide emulsion layer is provided directly thereon, it does not adhere firmly enough. Therefore, even when attempting to obtain a lithographic printing plate by plate-making processing such a photosensitive lithographic printing plate, the silver halide emulsion layer may peel off during the plate-making process (for example, during development of the silver halide emulsion layer). This made it impractical for practical use. In order to improve such drawbacks, for example, the specifications of U.S. Patent No. 3,245,793 and U.S. Defense Patent Application No. T.870022, as well as Japanese Patent Publication No. 47-23721, disclose that a UV-sensitive layer and a silver halide emulsion layer are It has been proposed to provide an intermediate layer in between. However, even when such an intermediate layer is provided, the adhesive force between the UV-sensitive layer and the silver halide emulsion layer may be insufficient, or conversely, this adhesive force may be too strong, resulting in damage to non-image areas. Because it becomes difficult to remove the emulsion layer or to remove the emulsion layer over the entire surface, the non-image areas of the resulting lithographic printing plate are easily smudged, and the image areas are oil-sensitive (i.e., oil-based). It had drawbacks such as poor ink-receptivity. Moreover, the provision of the intermediate layer increases the number of coating and drying steps, which is disadvantageous in manufacturing. Therefore, an object of the present invention is to provide a method for producing a photosensitive lithographic printing plate having a silver halide emulsion layer adhered with a desired strength on a layer containing an oleophilic resin such as an ultraviolet-sensitive layer. It is to be. Another object of the present invention is to provide a method for producing a photosensitive lithographic printing plate having a silver halide emulsion layer adhered to a layer containing an oleophilic resin with appropriate strength without intervening an intermediate layer. That's true. Still another object of the present invention is to have a silver halide emulsion layer directly on a layer containing an oleophilic resin, and the emulsion layer does not peel off during development processing, and is free from peeling after that. An object of the present invention is to provide a method for producing a photosensitive lithographic printing plate in which the non-image area or the entire surface of the emulsion layer can be removed by the above treatment. The inventors of the present invention have conducted intensive research to achieve the above object, and as a result, they have arrived at the present invention. A method for producing a photosensitive lithographic printing plate comprising providing a layer containing silver halide, coating a silver halide emulsion directly thereon, and drying the layer.
This manufacturing method is characterized in that after coating the silver halide emulsion, it is dried with hot air at 60°C to 150°C without setting. Generally, when a gelatin silver halide emulsion is coated in layers and dried, the temperature is first lowered after coating to allow it to set, and then the coated emulsion layer is dried by blowing air at a temperature within a range that does not melt it. is normal. When a gelatin silver halide emulsion is provided on a layer containing a lipophilic resin using this method, the gelatin silver halide emulsion is not adhered firmly enough and may easily peel off during the plate-making process. In very simple cases, the coated gelatin silver halide emulsion layer even peeled off during drying. On the other hand, when the gelatin silver halide emulsion is coated and dried by the method of the present invention, the gelatin silver halide emulsion layer adheres well to the layer containing the lipophilic resin, and the silver halide developer The emulsion layer does not peel off during development processing, and the non-image area of the emulsion layer or the entire emulsion layer can be removed by subsequent processing, for example, with hot water at 40°C to 60°C. It can bring about the desirable property of being able to do something. Furthermore, the method of immediately drying with hot air without setting the gelatin silver halide emulsion has good drying efficiency, and compared to the conventional method of setting and then drying, the manufacturing equipment is simpler and process control is easier. There is an advantage that the energy required for drying is drastically reduced. Furthermore, by adding a step of humidifying with water vapor in the latter stage of drying the silver halide emulsion layer in the method of the present invention, the adhesion between the layer containing the lipophilic resin and the silver halide emulsion layer becomes more stable. Furthermore, changes over time in the film quality of the photosensitive layer of the resulting photosensitive lithographic printing plate can be further reduced. The support with a hydrophilic surface used in the present invention can be selected from a variety of types. For example, paper, paper laminated with plastics (such as polyethylene, polypropylene, polystyrene, etc.), sheets of metal such as aluminum (including aluminum alloys), zinc, iron, copper, etc.
Plastic films, such as plastics such as cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.; Includes paper or plastic film on which metal is laminated or vapor-deposited. Among these supports, aluminum plates and composite sheets in which an aluminum sheet is bonded to a polyethylene terephthalate film as described in Japanese Patent Publication No. 18327/1984 are preferred. These supports are subjected to treatments such as surface treatment or formation of a hydrophilic layer, if necessary, in order to obtain a hydrophilic surface. There are various hydrophilic treatments.
For example, in the case of supports with plastic surfaces, so-called surface treatment methods such as chemical treatment, electric discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment (for example, US Pat. No. 2764520, No. 3497407,
No. 3145242, No. 3376208, No. 3072483, No. 3475193,
3360448, British Patent No. 788365, etc.). After such surface treatment, if necessary, for example, U.S. Pat.
A hydrophilic layer can be provided as described in No. 40890 and No. 53-61643. In addition, in the case of a support having a metal surface, especially aluminum, surface treatments such as graining treatment, immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, etc., or anodization treatment are performed. Preferably. In addition, as described in U.S. Patent No. 2,714,066, an aluminum plate that has been grained and then immersed in a sodium silicate aqueous solution, and as described in U.S. Pat. No. 3,181,461, an aluminum plate can be used as an anode. Those obtained by oxidation treatment and then immersion treatment in an aqueous solution of an alkali metal silicate are also suitably used.
The above anodic oxidation treatment is performed using, for example, phosphoric acid, chromic acid,
Phosphoric acid, sulfuric acid, or a combination of two or more of aqueous or non-aqueous solutions of inorganic acids such as sulfuric acid and boric acid, or organic acids such as oxalic acid and sulfamic acid, or their salts are particularly preferably used. It is carried out by passing an electric current through an aluminum plate in an aqueous solution of the mixture. Additionally, U.S. Patent No.
Silicate electrodeposition as described in No. 3,658,662 is also effective. Additionally, British Patent No.
Also preferred is an aluminum plate which is electrolyzed with alternating current in a hydrochloric acid electrolyte and then anodized in a sulfuric acid electrolyte, as described in No. 1208224. Further, it is preferable to provide an undercoat layer of a cellulose resin containing a water-soluble salt of a metal such as zinc on the aluminum plate anodized in the above process in order to prevent scum during printing. The first layer used in the present invention is different from the undercoat layer of a photosensitive material using general silver halide, and is different from the undercoat layer of a light-sensitive material using general silver halide, and is, for example, disclosed in Japanese Patent Publication No. 46-26521, Japanese Patent Application Laid-Open No. 47-2258,
Unlike the undercoat layer shown in publications such as No. 48-83902, No. 49-96803, and No. 49-96804, this layer contains a lipophilic resin. This first layer itself has the property of forming an image area that receives ink. A feature of the first layer containing the lipophilic resin is that it is soluble in an organic solvent other than water, such as a specific type of solvent selected from ketones, cellosolves, glycols, alcohols, and the like. The second feature is that it contains a lipophilic resin.
Lipophilicity refers to the property of easily accepting ink.
It can be defined as described in JP-A-52-154627. That is, a sample is prepared by coating a predetermined resin on a certain support to a thickness of about 2 μm or more, and the contact angle θ of the resin surface of the sample is measured. As suggested in Mitsuo Obana's ``Wetting Phenomena in Lithographic Printing'' in Print Magazine No. 25, October issue (1968), by the captive bubble method, a sample is soaked in water at 24°C and kerosene is applied to its surface. The contact angle of kerosene in water is θo/w using a goniometer. contact angle θ
Measure w/o. θ=−[θo/w−θw/
o] is positive, the resin is lipophilic. Specifically, such lipophilic resins include the following. Sierra Tsuk as described in British Patent No. 1350521, British Patent No. 1460978 and
Polymers containing hydroxyethyl acrylate units or hydroxyethyl methacrylate units as a main repeating unit as described in US Pat. No. 1,505,739; polyamide resins as described in US Pat. No. 3,751,257;
Phenolic resins as described in US Pat. No. 1,074,392 and polyvinyl acetal resins such as polyvinyl formal resins and polyvinyl butyral resins, linear polyurethane resins as described in US Pat. No. 3,660,097, polyaminostyrenes and polyvinyl Polymers containing amino groups such as alkylamino (meth)acrylate, celluloses such as cellulose acetate, cellulose alkyl ether, and cellulose acetate phthalate. Also contains novolac type phenolic resin,
Specifically, phenol formaldehyde resin,
Included are o-cresol formaldehyde resin, m-cresol formaldehyde resin, and the like. Furthermore, as described in JP-A-50-125806, in addition to the above-mentioned phenol resins, t-butylphenol formaldehyde resins having a carbon number of 3
It is even more preferable to use a condensate of formaldehyde and phenol or cresol substituted with an alkyl group of -8. For example, polyester compounds disclosed in JP-A-52-96696, British Patent No. 1112277, British Patent No. 1313390,
Polyvinyl cinnamate resins described in specifications such as No. 1341004 and No. 1377747, U.S. Patent No.
These include resins described in the specifications of No. 4072528 and No. 4072527. Particularly preferred are novolak type phenolic resins, cresol resins, polyester resins, polyvinyl cinnamate resins, and Sierrak. Further, an o-quinonediazide compound can be added to these resins, particularly preferably novolak type phenolic resins. Particularly preferred o-quinonediazide compounds are o-naphthoquinonediazide compounds, such as U.S. Pat.
No. 2859112, No. 2907665, No. 2907665, No. 2859112, No. 2907665, No.
No. 3046110, No. 3046111, No. 3046115, No. 3046118, No. 3046119, No. 3046120,
Same No. 3046121, Same No. 3046122, Same No. 3046123
No. 3061430, No. 3102809, No. 3102809, No.
It is described in numerous publications, including the specifications of No. 3106465, No. 3635709, and No. 3647443.
These can be suitably used. Among these, o-naphthoquinonediazide sulfonic acid esters of aromatic hydroxy compounds or o-
Preference is given to naphthoquinonediazidecarboxylic acid esters and o-naphthoquinonediazide sulfonic acid amides or o-naphthoquinonediazidecarboxylic acid amides of aromatic amino compounds, especially the condensates of pyrogallol and acetone as described in U.S. Pat. No. 3,635,709. and o-naphthoquinonediazide sulfonic acid, and o-naphthoquinonediazide sulfonic acid or o-naphthoquinonediazidecarboxylic acid is esterified with a polyester having a hydroxyl group at the end described in U.S. Pat. No. 4,028,111. What reacted,
Homopolymers of p-hydroxystyrene or copolymers thereof with other copolymerizable monomers, as described in British Patent No. 1494043, are combined with o-naphthoquinone diazide sulfonic acid or o-
The product obtained by ester reaction of naphthoquinonediazidecarboxylic acid is very good. These resins are dissolved in an organic solvent and applied by a commonly used coating method so as to have a dry weight of about 0.1 g to 5 g, and are used as the first layer. A silver halide emulsion layer is provided directly on the first layer. The silver halide emulsion used in the present invention may be, for example, gelatin, a negative type emulsion or a direct positive type emulsion, and US Pat.
No. 3118766, No. 3186846, Special Publication No. 39-5514
Hydrophilic gelatin derivatives, casein, sodium alginate, cellulose derivatives, polyvinyl alcohol partial acetal, polyvinyl pyrrolidone, polyacrylamide, polyvinyl imidazole, polyvinyl pyrazole, and other homo or copolymers described in No. 42-26845, etc. Silver bromide, silver chloride, silver iodide, or a mixed silver halide thereof is dispersed in a sexually protective colloid. Preferably, in a protective colloid containing at least gelatin or gelatin derivative, 0.01μ
Mixed silver halide grains having an average grain size of 2 to 2 microns are dispersed therein. Even if silver halide grains are not sensitized, chemical sensitization methods such as sulfur sensitization, reduction sensitization, sensitization with noble metal salts such as Ir, Rh, Pt, and Au, and sensitizing dyes are used to ensure appropriate sensitivity. It is possible to perform spectral sensitization using desensitizing dyes or desensitizing dyes. Further, any particle having a surface latent image type or internal latent image type latent image distribution may be used. These are “Chimie” by P. Grafikides.
Photographique" Paul Montel published in 1957, the ammonia method, neutral method,
It is produced by using methods such as the acid method or the single, double-jet, and controlled double-jet methods. The protective colloid is used in an amount of about 10 to 200 g per 1 kg of emulsion. Silver halide emulsions include active vinyl compounds such as divinyl sulfone and methylene bismaleimide, and 2,4-
Small amounts of highly active hardeners such as active halogen compounds such as dichloro-6-hydroxy-s-triazine may also be added. In addition, commonly used additives such as stabilizers, antifoggants,
Coating aids such as surfactants and dyes or pigments may also be added. If necessary, for example, hydroquinone, a hydroquinone derivative, catechol, a catechol derivative, pyrogallol or a derivative thereof can be dispersed and incorporated into the silver halide emulsion layer. Furthermore, a resin such as a phenolic resin can be dispersed and incorporated into the silver halide emulsion layer. These silver halide-containing photosensitive layers are deposited on the subbing layer in an amount of about 1 to 10 g/m ² , preferably 2 g/m 2 .
A dry amount of 6 g/m ² can be applied. This application can be done using dip, air knife, curtain or other methods such as US Pat.
The hopper coating method or the extrusion coating method described in No. 2681294 can be applied. The silver halide emulsion layer coated on the first layer is
As mentioned above, it is dried using hot air at 60°C to 150°C without being set. In the present invention, the initial drying is performed by applying hot air at a temperature of 60°C to 100°C to increase the viscosity of the coating film, and the late drying is performed by applying hot air at a temperature of 70°C to 150°C with a relatively low temperature gradient. It is preferable to gradually dry it by applying it strongly. The silver halide emulsion layer dried in this manner adheres to the first layer with appropriate strength. A method for making a lithographic printing plate using the photosensitive lithographic printing plate produced according to the present invention is as follows. For example, imagewise exposure is performed as described in Japanese Patent Application No. 52-50907 and Japanese Patent Application No. 54-57433 to form a latent image in the form of an image on the silver halide emulsion layer. Next, silver halide development (first development) is performed, and the film is sent to the first layer development process (second development) either immediately or through a process of processing with a fixer or washing out only the undeveloped areas. As a result, a lithographic printing plate can be obtained in which the first layer containing at least a lipophilic resin is exposed in the image area and the hydrophilic surface of the support is exposed in the non-image area. That is,
First, only the undeveloped area of the silver halide emulsion layer is washed out, and then the first layer is dissolved and the image area consisting of the silver halide emulsion layer containing blackened silver is treated with a processing solution that does not dissolve the halogen. This is a step in which the first layer corresponding to the washed out portion of the silver emulsion layer is removed to expose the hydrophilic surface of the support to obtain a printing plate. This treatment liquid is an organic solvent that is insoluble in water or a type of treatment liquid that is dispersed in an aqueous system. The second step is to process it with a fixer, wash out only the undeveloped areas, or immediately expose it to ultraviolet light and send it to the second development, where only the non-image areas dissolve and remove the first layer to obtain a printing plate. . In this case, the processing solution for the second development is applied to the first development solution in the non-image area.
A processing solution that selectively dissolves only the layers is required.
In particular, it can be selected from the developers used for developing PS plates using conventional non-silver salt photosensitive layers or similar developers. In this case, the first layer of the photosensitive lithographic printing plate used in the present invention must contain a photosensitive compound active to ultraviolet light, such as an o-quinone diazide compound or a polyvinyl cinnamate resin. . Thirdly, in the second case, after exposure to ultraviolet rays, a step of washing out the silver halide emulsion layer on the first layer on the entire surface or only in the non-image area can be included. The next step is to bring it into contact with a second developer to selectively dissolve and remove only the non-image areas. The content of the present invention will be specifically explained below using Examples. Note that % indicates weight %. Example 1 A 2S aluminum plate mechanically grained using the method disclosed in JP-A-48-33911 was immersed in a 2% sodium hydroxide aqueous solution kept at 40°C for 1 minute to corrode a portion of the surface. . After washing with water, it was immersed in a sulfuric acid monochromic acid solution for about 1 minute to expose the pure aluminum surface. It was immersed in 20% sulfuric acid kept at 30°C, anodized for 2 minutes at a DC voltage of 1.5V and a current density of 3A/dm ² , then washed with water and dried. Next, an undercoat liquid having the following composition was continuously applied using an extrusion type Giesser so that the dry weight was about 2 g/m ² .

[Table] Next, the coating solution of the following photosensitive layer formulation (1) was applied continuously at a speed of 10 m/min at 35°C using an extrusion type Giesser so that the dry weight was 4.0 g/m ^2. Samples 1 to 5 were obtained by applying the sample uniformly to the drying zone and then sending it to a drying zone under the following conditions. Separately, after coating, it was set and dried at 4°C for 3 minutes. In sample-a, the film peeled off during drying.

[Table] In Samples-1 to 5, no defects like those in Sample-a occurred.

[Table] After the samples were left at room temperature for one week, they were subjected to the plate-making process as follows. A transparent negative film obtained by photographing character lines after being reduced to about 1/5 was exposed to light for 10 seconds at 5x magnification using an enlarger equipped with a 300 lux light source. Next, the following processing was performed using an automatic developing machine. A first developing section filled with a developer () with the following composition is passed through it at 32°C for 20 seconds.
Place the fixing section filled with the following fixer () at room temperature.
It took 10 seconds to pass through. Next, it is passed through an ultraviolet exposure section consisting of three reflective mercury lamps for 15 seconds, and at the washing section, it is immersed in warm water at 40-45℃ and rubbed with a brush, passed through a squeeze roller, and a developer solution () with the following composition is applied. The filled second developing section was heated to 30℃ for 30 minutes.
It was allowed to cool down for a few seconds, and then gummed with a 14° Be gum arabic aqueous solution to obtain a lithographic printing plate. Composition of developer () Water 700 ml Metol 3.0 g Sodium sulfite 45.0 g Hydroquinone 12.0 g Sodium carbonate (monohydrate) 80.0 g Potassium bromide 2 g Add water to make 1. This stock solution is diluted with water (1:2) and used. Developer solution () JIS No. 1 sodium silicate 100g Sodium metasilicate 50g Pure water 1800ml Fixer solution () Water 700ml Ammonium thiosulfate 224g Sodium sulfite 20g Add water to make 1000ml. With each printing plate thus obtained, Heidel
Printed using a KOR printing machine. The lithographic printing plates prepared from Samples 1 to 5 all produced good prints with a print count of 4 to 5 sheets, and had a printing life of about 110,000 copies.

Claims (1)

[Claims] 1. A method for producing a photosensitive lithographic printing plate, which comprises providing a layer containing a water-insoluble lipophilic resin on a support having a hydrophilic surface, directly coating a silver halide emulsion thereon, and drying the layer. After coating the silver halide emulsion, 60°C was applied without setting.
A manufacturing method characterized by drying with hot air at a temperature of 150°C.