JP2622769B2 - Manufacturing method of photosensitive printing plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a photosensitive printing plate, and more particularly to a method for producing a photosensitive printing plate having a matted photosensitive layer.

[Conventional technology]

Various methods are known for a method of matting the surface of a photosensitive printing plate or a method of manufacturing a matted photosensitive printing plate.

For example, Japanese Patent Publication No. Sho 57-6582 discloses a method in which a photosensitive layer is applied to a support, and a solution in which various powders are dispersed by a gravure roller is applied to the photosensitive layer to form irregularities.
Japanese Patent Application Laid-Open No. 61-48994 discloses a method in which various aqueous solutions are applied on a photosensitive layer by electrostatic coating to make the surface uneven.
Japanese Patent Application Laid-Open No. 55-12974 discloses a method of thermally fusing powder onto a photosensitive layer. Furthermore, British Patent No. 174588 discloses a method in which a liquid having the same composition as that of the photosensitive layer is spray-coated on the surface of the photosensitive layer to form a discontinuous layer and the surface is made uneven.

JP-A-54-12905 describes a method in which various powders are dispersed in a photosensitive solution, applied by a roller having irregularities, and a photosensitive layer is provided.

[Problems to be solved by the invention]

As described above, various methods have been described as methods for matting the surface of a photosensitive printing plate.
The method of providing a mat layer on a photosensitive layer described in JP-A No. 61-48994, JP-B-55-12974 and British Patent No. 174588 discloses that the number of steps is increased by one step and / or In some cases, there is a problem that the mat layer easily falls off.

In addition, the method disclosed in JP-A-54-12905, in which powder is dispersed in a photosensitive solution, has the disadvantage that the powder agglomerates to cause a failure.

An object of the present invention is to provide a mat which can prevent the problems of the prior art, that is, an increase in the number of steps, peeling of a matting agent formed on a coated surface in a later manufacturing process, and collapse of an image due to agglomeration of powder. It is to provide a method.

[Means and actions for solving the problem]

The object of the present invention is to provide a photosensitive printing plate support, comprising: sending atomized particles of a preliminarily atomized photosensitive coating solution via a transport pipe to a discharge opening larger than the transport pipe; A charge is applied from the electrodes disposed on the photosensitive layer, and the particles of the thus-obtained atomized and charged photosensitive layer coating solution are electrostatically attached to the photosensitive coating film having irregularities on its surface. Forming a photosensitive printing plate.

Achieved by

The coating solution of the photosensitive layer of the present invention can be made into particles of the coating solution in an atomized state by an atomizing device as exemplified in FIG.

The charged particles of the photosensitive layer coating liquid in the atomized state are charged by applying a charge to the atomized particles of the coating liquid from an electrode disposed inside the discharge opening.

 Preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows that the photosensitive layer coating solution is preliminarily atomized and then charged to obtain charged particles of the photosensitive layer coating solution in the atomized state, and the particles of the photosensitive layer coating solution are electrostatically adhered and coated. It is a schematic sectional drawing of the process of forming a film layer.

The photosensitive layer coating solution is atomized in an atomizing chamber 12 by an atomizing device 11 such as an ultrasonic atomizer, a rotary bell, or a spray nozzle, and becomes particles of the atomized photosensitive layer coating solution. The particles of the photosensitive layer coating solution are carried by the carrier gas 10 and reach the outlet 4 as an opening from the atomization chamber through the transport pipe 5. Among the particles of the photosensitive layer coating liquid, those having a large diameter collide with the atomizing chamber 12 and the wall surface of the transport pipe 5 before reaching the outlet 4 and are removed.

Evaporation of the solvent in the particles up to the outlet increases the viscosity of the particles. The particles of the photosensitive layer coating solution that has reached the outlet 4 are charged by the electrodes 7 and electrostatically adhered to the support 1, whereby a photosensitive layer coating layer having irregularities on the surface of the support 1 can be formed. . Support 1 is a pass roller
It is guided by 2, 3 and 8.

FIG. 2 is a perspective view of the vicinity of the air outlet 4 in FIG. Although the outlet having the electrode 7 is rectangular, the particles of the photosensitive layer coating liquid in the atomized state are charged by the electrode 7 and charged,
The coating film layer is formed by electrostatically adhering to the support 1 in a laminar flow state. There are no detailed restrictions on the shape of the outlet.

The state of the surface irregularities changes depending on the conditions of the atomization method, for example, the bell shape and the number of revolutions in the case of the rotary bell system, the spray nozzle diameter in the case of the spray system, and the diameter of the atomized particles of the coating solution and the application. It depends on many factors such as the solvent composition and viscosity of the liquid.

FIG. 3 shows an example in which two air outlets are provided side by side in the traveling direction of the support, and the number of air outlets provided is not limited.

The atomized particle size is preferably 150 μm or less, more preferably 80 μm or less.

By providing multiple outlets as shown in FIG. 3, the diameter of the atomized particle of the photosensitive coating liquid discharged from the first outlet and the second outlet is changed to obtain an appropriate uneven pattern. Can also. Normally, it is preferable to apply the coating by the next blow-out port in a state where the coating by the first blow-out port is not dried since drying in the middle can be omitted. Coating by an outlet may be performed.

For example, the particle diameter becomes large at the first outlet, for example, about
After attaching with 200μm droplets, about 1
It is also possible to attach a droplet of 00μ, or the reverse method.

By the above-mentioned various coating film forming methods, by forming a coating film with irregularities, and then dried in the drying zone 9,
An uneven coating film can be formed.

Unevenness on the surface can be made up to about 20 μm.

As the photosensitive printing plate in the present invention, a lithographic printing plate,
Supports used for making printing plates such as letterpress printing plates and intaglio printing plates are included.

Examples of the support include those conventionally used as a support for printed matter as a dimensionally stable plate-like material, which can be suitably used in the present invention.

Examples of such a support include paper, paper laminated with plastics (eg, polyethylene, polypropylene, polystyrene, etc.), a metal plate such as aluminum (including aluminum alloy), zinc, iron, copper, etc., and cellulose diacetate. Plastic films such as cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc., and the above-mentioned metals were laminated or vapor-deposited. Paper or plastic film is included. An appropriate one is selected from these supports depending on the type of the printing plate. For example, in the case of a photosensitive lithographic printing plate, an aluminum plate, a composite sheet in which an aluminum sheet is bonded to a polyethylene terephthalate film described in JP-B-48-18327, and the like are preferable. In the case of a photosensitive relief printing plate, a polyethylene terephthalate film, an aluminum plate, an iron plate or the like is preferable.

The support is surface-treated as necessary. For example, in the case of a photosensitive lithographic printing plate, the surface of the support is subjected to a hydrophilic treatment. There are various types of such hydrophilic treatment. For example, in the case of a support having a plastic surface, a so-called surface treatment method such as chemical treatment, discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, etc. 2,764,520
Nos. 3,497,407, 3,145,242, 3,376,208
No. 3,072,483, No. 3,475,193, No. 3,360,448, and British Patent No. 788,365), and a method of applying an undercoat layer to the plastic after the surface treatment.

In the case of a support having a surface of a metal, particularly aluminum, a surface treatment such as graining, immersion in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, or anodizing is performed. Is preferred. Also, as described in U.S. Pat.No. 2,714,066, an aluminum plate grained and then immersed in an aqueous solution of sodium silicate, U.S. Pat.
As described in the specification of JP-A No. 1, an aluminum plate that has been subjected to anodizing treatment and then immersed in an aqueous solution of an alkali metal silicate is also preferably used. The anodizing treatment may be performed, for example, by using an inorganic acid such as phosphoric acid, chromic acid, sulfuric acid or boric acid, or an organic acid such as oxalic acid or sulfamic acid, or an aqueous or non-aqueous solution of a salt thereof alone or in an aqueous solution.
It is carried out by flowing a current in an electrolytic solution combining a plurality of types with an aluminum plate as an anode.

Also, silicate electrodeposition as described in US Pat. No. 3,658,662 is effective.

These hydrophilic treatments are performed not only to make the surface of the support hydrophilic, but also to prevent harmful reactions with the photosensitive composition provided thereon, and to improve the adhesiveness with the photosensitive layer. This is done for improvement.

The photosensitive substance provided on the support can be used as long as its solubility or swelling property in a developer changes before and after exposure. For example, (1) a composition comprising a diazo resin.

The diazo resin represented by a condensate of p-diazodiphenylamine and paraformaldehyde may be a water-soluble one or a water-insoluble one, but preferably a water-insoluble one and one soluble in a common organic solvent. used. Particularly preferred diazo compounds include salts of condensates of p-diazophenylamine with formaldehyde or acetaldehyde, such as phenol salts, fluorocaprinates,
And triisopropylnaphthalenesulfonic acid, 4,4-biphenyldisulfonic acid, 5-nitroortho-toluenesulfonic acid, 5-sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-
Chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-chloro-5-nitrobenzenesulfonic acid, 2
-In one molecule such as salts of sulfonic acids such as fluorocaprylnaphthalenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid and paratoluenesulfonic acid. It is a compound having two or more diazo groups. Other desirable diazo resins include the above salts, condensates of 2,5-dimethoxy-4-p-tolylmercapton benzenediazonium and formaldehyde, and 2,5-dimethoxy-4-monophorinobenzenediazonium with formaldehyde or acetaldehyde. And a condensate of

Further, diazo resins described in British Patent No. 1,312,925 are also preferable.

The diazo resin can be used alone as a photosensitive material used for forming a resist, but is preferably used together with a binder.

As such a binder, various polymer compounds can be used, and hydroxyamino, carboxylic acid amide,
Those containing groups such as sulfonamide, active methylene, thioalcohol and epoxy are preferred. Such preferred binders include hydroxyethyl acrylate units or hydroxyethyl as described in British Patent 1,350,521, Shellac, British Patent 1,460,978 and U.S. Patent 4,123,276. Polymers containing methacrylate units as main repeating units, polyamide resins described in U.S. Pat.No. 3,751,257, phenolic resins described in British Patent 1,074,392 and for example polyvinyl formal resins, polyvinyl butyrate Acetal resin such as color resin, linear polyurethane resin described in US Pat. No. 3,660,097, phthalated resin of polyvinyl alcohol, bisphenol A
And epoxy resins condensed from epichlorohydrin and polymers containing amino groups such as polyaminostyrene and polyalkylamino (meth) acrylate, and celluloses such as cellulose acetate, cellulose alkyl ether, and cellulose acetate phthalate.

The content of the binder is suitably from 40 to 95% by weight in the photosensitive resist-forming composition. If the amount of the binder increases (that is, if the amount of the diazo resin decreases), the photosensitivity naturally increases, but the temporal stability decreases. The optimal amount of binder is about 70-90% by weight.

Compositions comprising diazo resins further include U.S. Pat.
Additives such as phosphoric acid, dyes and pigments described in 6,646, specification can be added.

(2) Composition comprising an o-quinonediazide compound A particularly preferred o-quinonediazide compound is an o-naphthoquindiazide compound, for example, US Pat. No. 2,766,118.
No. 2,767,092, 2,772,972, 2,859,11
No. 2, No. 2,907,665, No. 3,046,110, No. 3,046,1
No. 11, No. 3,046,115, No. 3,046,118, No. 3,046,
No. 119, No. 3,046,120, No. 3,046,121, No. 3,04
No. 6,122, No. 3,046,123, No. 3,061,430, No. 3,1
No. 02,809, No. 3,106,465, No. 3,635,709, No. 3,
It is described in a number of publications including each specification of 647,443, and these can be suitably used. Among these, o-naphthoquinonediazidosulfonic acid ester or o-naphthoquinonediazidocarboxylic acid ester of an aromatic hydroxy compound, and o-naphthoquinonediazidesulfonic acid amide or o-naphthoquinonediazidecarboxylic acid amide of an aromatic amino compound are particularly preferable. In particular, those obtained by subjecting a condensate of pyrogallol and acetone described in U.S. Pat.No. 3,635,709 to an ester reaction with o-naphthoquinonediazidosulfonic acid, and having a terminal at the terminal described in U.S. Pat.No.4,028,111. O-naphthoquinonediazidosulfonic acid or o-naphthoquinonediazidecarboxylic acid obtained by subjecting a polyester having a hydroxy group to an ester reaction, a homopolymer of p-hydroxystyrene as described in British Patent No. 1,494,043, or That the copolymer in the o- naphthoquinonediazide sulfonic acid or o- naphthoquinonediazide carboxylic acid with a monomer capable of other copolymerizable by esterification reaction is very good.

These o-quinonediazide compounds can be used alone and used, but are preferably used in combination with an alkali-soluble resin. Suitable alkali-soluble resins include novolak-type phenolic resins, and specifically include phenol-formaldehyde resins, o-cresol-formaldehyde resins, m-cresol-formaldehyde resins, and the like. Further, as described in U.S. Pat. No. 4,123,279, together with the above-mentioned phenol resin, a formaldehyde and a phenol or cresol substituted with an alkyl group having 3 to 8 carbon atoms such as a t-butylphenol formaldehyde resin are used. It is even more preferred to use the compound together with a compound. Further, a vinyl compound having a phenolic OH group as disclosed in JP-A-62-279327 or a polymer compound having a sulfonamide group as disclosed in JP-A-2-866 is also used. The alkali-soluble resin comprises about 50-85% by weight, more preferably 60-80% by weight, based on the total weight of the photosensitive resist-forming composition.
% By weight.

The photosensitive composition comprising the o-quinone dithiide compound may further contain a pigment, a dye, a plasticizer, a surfactant as a coating aid, and the like, if necessary.

(3) Composition comprising a photosensitive azide compound A suitable photosensitive azide compound is an aromatic azide compound in which an azide group is bonded to an aromatic ring directly or via a carbonyl group or a sulfonyl group. In these, azide groups are decomposed by light to produce nitrene, and nitrene undergoes various reactions to be insolubilized. Preferred aromatic azide compounds are compounds containing one or more groups such as azidophenyl, azidostyryl, azidobenzal, azidobenzoyl and azidocinnamoyl, for example, 4,4'-diazidochalcone, 4-azido-
4 '-(4-azidobenzoylethoxy) chalcone, N,
N-bis-p-azidobenzal-p-phenylenediamine, 1,2,6-tri (4'-azidobenzoxy) hexane, 2-azido-3-chloro-benzoquinone, 2,4-diazide-4'-ethoxyazobenzene, 2,6-di (4 '
-Azidobenzal) -4-methylcyclohexanone, 4,
4'-diazidobenzophenone, 2,5-diazide-3,6-
Dichlorobenzoquinone, 2,5-bis (4-cididostyryl) -1,3,4-oxadiazole, 2- (4-azidocinnamoyl) thiophene, 2,5-di (4′-azidobenzal) cyclohexanone, 4'-diazidodiphenylmethane, 1- (4-azidophenyl) -5-furyl-2
-Penta-2,4-dien-1-one, 1- (4-azidophenyl) -5- (4-methoxyphenyl) -penta-
1,4-dien-3-one, 1- (4-azidophenyl)
-3- (1-Naphthyl) propen-1-one, 1- (4
-Azidophenyl) -3- (4-dimethylaminophenyl) -propan-1-one, 1- (4-azidophenyl) -5-phenyl-1,4-pentadien-3-one,
1- (4-azidophenyl) -3- (4-nitrophenyl) -2-propen-1-one, 1- (4-azidophenyl) -3- (2-furyl) -2-propen-1-one , 1,2,6-tri (4'-azidobenzoxy) hexane, 2,6-bis- (4-azidobenzylidine-pt-
Butyl) cyclohexanone, 4,4'-diazidodibenzylacetone, 4,4'-diazidostilbene-2,2'-disulfonic acid, 4'-azidobenzalacetophenone-2-
Sulfonic acid, 4,4'-diazidostilbene-α-carboxylic acid, di- (4-azido-2'-hydroxybenzal)
Acetone-2-sulfonic acid, 4-azidobenzalacetophenone-2-sulfonic acid, 2-azido-1,4-dibenzenesulfonylaminonaphthalene, 4,4'-diazide-
Stilbene-2,2'-disulfonic acid anilide and the like can be mentioned.

In addition to these low molecular weight aromatic azide compounds, JP-B-44-9047, JP-B-44-31837, JP-B-45-9613, and JP-B-45-9613.
No. 24915, No. 45-25713, JP-A No. 50-5102, No. 50-
The azide group-containing polymers described in JP-A Nos. 84302, 50-84303 and 53-12984 are also suitable.

These photosensitive azide compounds are preferably used together with a polymer compound as a binder. Preferred binders include alkali-soluble resins, for example, natural resins such as shellac and rosin, for example, novolak-type phenol resins such as phenol formaldehyde resin and m-cresol formaldehyde resin, for example, polyacrylic acid, polymethacrylic acid, and methacrylic acid-styrene. Polymer, methacrylic acid-methyl acrylate copolymer,
A homopolymer of an unsaturated carboxylic acid such as a styrene-maleic anhydride copolymer or a copolymer thereof with another copolymerizable monomer, a partially or completely saponified product of polyvinyl acetate is used, for example, acetaldehyde, benzaldehyde, hydroxy Resins partially acetalized with aldehydes such as benzaldehyde and carboxybenzaldehyde, and polyhydroxystyrene are included. Further, organic solvent-soluble resins such as cellulose alkyl ethers such as cellulose methyl ether and cellulose ethyl ether can be used as the binder.

The binder is preferably contained in the range of about 10% by weight to about 90% by weight based on the total weight of the composition comprising the photosensitive azide compound.

The composition comprising the photosensitive azide compound may further contain a dye or a pigment, for example, a plasticizer such as a phthalic acid ester, a phosphoric acid ester, a fatty acid carboxylic acid ester, a glycol or a sulfonamide, for example, Michler-ketone, 9-fluorenone, -Nitropyrene, 1,8-dinitropyrene, 2-
Chloro-1,2-benzanthraquinone, 2-bromo-1,2
-Benzanthraquinone, pyrene-1,6-quinone, 2-
Additives such as sensitizers such as chloro-1,8-phthaloylnaphthalene and cyanoacridine can be added.

(4) In the main chain or side chain of the polymer A composition comprising a high molecular compound containing a polymer as a photosensitive group on the main chain or side chain of the polymer Those containing as a main component a photosensitive polymer such as polyesters, polyamides, and polycarbonates (for example, US Pat. Nos. 3,030,208, 3,707,373 and 3,45).
3,237).
(2-Proveridene) malonic acid compounds such as cinnamylidenemalonic acid and photosensitive polyesters derived from bifunctional glycols as main components (for example, US Pat. Nos. 2,956,878 and 3,173,787) Cinnamate esters of hydroxyl-containing polymers such as polyvinyl alcohol, starch, cellulose and the like (see, for example, US Pat.
No. 690,966, 2,752,372, 2,732,301, etc.) and the like. In these compositions, other sensitizers, stabilizers,
A plasticizer, a pigment, a dye, and the like can be included.

〔Example〕

Example-1 A 2S aluminum plate having a thickness of 0.2 mm was immersed in a 10% aqueous solution of sodium triphosphate and an aqueous solution maintained at 80 ° C for 3 minutes to degrease it. After graining using this aluminum plate,
Anodized in 20% sulfuric acid, washed with water and dried to prepare an aluminum plate as a support.

A liquid having the following composition is applied to this aluminum plate in the manner shown in FIG. 1 by applying the above-mentioned atomized particles to give electrostatic charge to form irregularities on the surface of the support 1, and then dried and dried. Provided a photosensitive layer having an average weight of 3.0 μm and an average weight of 2.5 g / m ² .

Coating solution composition: Naphthoquinone- (1,2) -diazide- (2) -5-sulfonic acid chloride and poly-p-hydroxyethylene ester compound 7 parts by weight Novolac-type phenol resin 20 parts by weight Methyl ethyl ketone 32.4 parts by weight Methyl cellosolve Acetate 75.6 parts by weight The sample prepared as described above was superimposed on a film base plate (550 mm / 600 mm) and the vacuum adhesion time was examined by a vacuum adhesion printer.

Furthermore, after passing between the rubber nip rollers 5 times and 10 times, the vacuum contact time and the adhesion of the matting agent to the rollers were similarly examined. The roller used was a urethane rubber roller having a hardness of 70 mm. The results are shown in Table 1.

From the above results, it can be seen that the matting agent does not fall off and the vacuum contact time does not change significantly even after passing many nip rollers by the manufacturing method according to the present invention.

Example-2 A 2S aluminum plate having a thickness of 0.2 mm was immersed in a 10% aqueous solution of tribasic sodium phosphate kept at 80 ° C for 3 minutes to degrease it.
After graining with a nylon brush and 400 mesh Pamistone-water suspension, the aluminum plate was
Anodization was performed in sulfuric acid, followed by washing with water and drying to prepare an aluminum plate as a support.

A liquid having the following composition is first applied to the aluminum plate by the method shown in FIG. 3 to a weight of about 70% at the first outlet 4a, and then is applied to the aluminum plate by 20% more than the second outlet 4b. The remaining amount is atomized with droplets, and each particle is applied by applying an electrostatic charge to the electrodes 7a and 7b to form a coated surface having irregularities on the surface, and then dried, and the irregularities are averaged at 3.7 μm on average. Weight 2.4
g / m ² photosensitive layer was provided.

Coating liquid composition: Naphthoquinone- (1,2) -diazide- (2) -5-sulfonic acid chloride and poly-p-hydroxyethylene ester compound 7 parts by weight Novolak-type phenol resin 20 parts by weight Methyl ethyl ketone 32.4 parts by weight Methylcellosolve Acetate 75.6 parts by weight The sample thus prepared was superimposed on a film base plate (550 mm / 600 mm), and the vacuum adhesion time was measured by a vacuum adhesion printer. Further, after passing between the rubber nip rollers 5 times and 10 times, the vacuum contact time and the adhesion of the matting agent to the rollers were similarly examined. The roller used was a urethane rubber roller having a hardness of 70 mm.
The results are shown in Table 2.

From the above results, it can be seen that the manufacturing method according to the method of the present invention does not cause the matting agent to fall off as seen in the conventional method, and that the vacuum contact time does not change significantly even after passing many nip rollers.

〔The invention's effect〕

According to the method for producing a photosensitive printing plate of the present invention, the application of the photosensitive liquid and the application of the matting agent can be simultaneously performed, the equipment can be simplified, and the matting agent can be prevented from falling off, thereby improving the quality and reducing the cost. Contributed.

[Brief description of the drawings]

1, 3 and 4 are schematic cross-sectional views of one embodiment of the method for producing a photosensitive printing plate of the present invention, and FIG. 2 is a perspective view of the vicinity of the air outlet of the present invention. 1 ... Support 2,3,8 ... Pass rollers 4,4a, 4b ... Outlet 5 ... Transport pipe 6 ... Electrode cable 7,7a, 7b ... Electrode 9 ... Drying zone, 10 ... Transport gas 11: atomizer, 12: atomization chamber 13: ultrasonic atomizer

Continuation of front page (56) References JP-A-2-43554 (JP, A) JP-A-59-219751 (JP, A) JP-A-60-205544 (JP, A) JP-A-3-215931 (JP, A) JP-A-3-194558 (JP, A) JP-A-1-99473 (JP, U)

Claims (1)

(57) [Claims] 1. A mist-like particle of a photosensitive coating solution which has been previously atomized on a support of a photosensitive printing plate is sent through a transport pipe to a discharge opening larger than the transport pipe, and is disposed inside the opening. A charge is applied from the electrode thus formed, and the particles of the thus-obtained atomized and charged photosensitive coating liquid are electrostatically adhered to form a photosensitive coating film having irregularities on its surface. A method for producing a photosensitive printing plate, comprising: