JPS59126537A - Manufacture of lithographic printing plate - Google Patents

Abstract

PURPOSE:To obtain a lithographic printing plate having superior printing resistance, ink retentivity and printing characteristics and causing no ground stain by developing exposed silver halide with an alkali activating bath contg. a solvent for silver halide and a specified compound. CONSTITUTION:A printing plate having a photosensitive silver halide layer contg. a silver halide developing agent and a layer of physical developing nuclei on a support is exposed and developed with an alkali activating bath contg. a solvent for silver halide and 0.01-50g/l compound represented by the formula [where Z is a group of nonmetallic atoms required to complete an (un)substituted 5- or 6-membered heterocyclic ring such as thiazoline, benzothiazole, oxazline, exazole, imidazoline, (benz)imidazle, oxadiazole or thiadiazole]. A solver image formed by a silver salt diffusion method can be made receptive to lipophilic ink.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention, etc.] The present invention relates to a method for manufacturing a lithographic printing plate. More specifically, the present invention relates to a method for producing a direct lithographic printing plate in which a silver image formed by a silver salt diffusion transfer method is made receptive to oleophilic ink.

[Prior art]

Conventionally, many methods have been known for manufacturing lithographic printing plates using the silver salt diffusion transfer method, and representative ones include US Pat. No. 3,344.741 and US Pat.
The methods described in the specifications of No. 161,508, Japanese Patent Publication No. 48-16725, etc. are known. Also, special public service in 1977
There are also methods described in Publications No. 42453 and No. 48-30562. In the former method, the photographic element with the photosensitive layer and the development nucleus layer, which is the printing edge element, are each made up of separate units, whereas the latter is a technology in which they are integrated. be.

Another method is disclosed in US Pat. No. 3,511. ．． 65
No. 6 and No. 3,557,690, etc. This method involves diffusing and transferring a photographic element having a photosensitive layer provided as an uppermost layer to a lower printed image element, and then A printing plate is obtained by leaching and peeling off the upper layer with water. A typical processing solution for a lithographic printing material to which the silver salt diffusion transfer method is applied, in which the main constituent layers are a photosensitive silver halide emulsion layer and a physical removable nucleus layer, is a developing agent, a silver halide solvent, and a silver halide solvent. It contains at least an alkaline agent.

In order to apply a silver image obtained by such a diffusion transfer method as an offset printing plate, it is necessary to increase the ink receptivity, ie, water repellency, of the silver image area, and to increase the ink repulsion, ie, hydrophilicity, of the non-image area. is important.

Many techniques have been proposed for this purpose (for example, Tokoku No. 4B-30562, Tokoku No. 486, No. 51-486, Tokoku No. 5
No. 4-2027 and JP-A No. 56-135840 disclose that in a lithographic printing material applying a silver salt diffusion transfer method, when a constituent layer contains a developing agent in an amount that can be developed in an alkaline bath. At present, the conventional methods described above are not necessarily sufficient.

[Purpose of the invention]

An object of the present invention is to provide a method for producing a lithographic printing plate that has excellent printing durability and ink receptivity, and has excellent printing properties without staining.

[Structure of the invention]

The present invention provides a method for producing a lithographic printing plate applying a silver salt diffusion transfer method in which a constituent layer contains a developing agent in an amount capable of developing exposed silver halide in an alkaline activation bath.
The alkaline activation bath is characterized in that it contains a silver halide solvent and at least one compound represented by the following co-synthesis [13].

General formula [1,) In the formula, 2 is a group of nonmetallic atoms necessary to complete a substituted or unsubstituted 5- to 6-membered heterocycle, and the heterocycle includes a thiazoline nucleus, a thiazole nucleus, a benzothiazole nucleus, Oxazoline nucleus, oxazole nucleus, benzoxazole nucleus, imidacilline nucleus, imidazole nucleus, benzimidazole nucleus,
selected from oxadiazole nucleus, thiadiazole nucleus, triazine nucleus, selenazole nucleus, benzoselenazole nucleus, pyridine nucleus, pyrimidine nucleus and quinoline nucleus.

Silver halide solvents used in the present invention include sodium thiosulfate, thorium thiocyanate, potassium thiocyanate, alkanolamines, cyclic amines, alkyl-substituted amino alcohols, thiourea, thiosalcylic acid, and thiosalcylic acid that forms in an alkaline solution. For example, 5-methylcarbamoylthiosalicylic acid and the like can be mentioned.

Particularly preferred heterocycles in the general formula C1'3VC include those represented by the following general formulas [''] to [v].

General formula [111 General formula [13 2 Desired general formula [IV] 7- [In the formula, R1, tL2, R3, ll'l, R5
, R6, R7, R8, R9 and R10 are CI
NCg alkyl group, C2-CB allyl group, mercapto group, C1-C8 alkylthio group, hydroxyl group, C1-C
F! represents an alkoxy group, amine group, alkylamino group, acylamino group or aryl group.

] Specific compounds are described below.

[Exemplary compounds]

-N -N -N -N Among these, the most preferable one is the exemplified compound ill
and (5).

In the present invention...silver emulsion and general formula [■]
The amount of the compound added is 0.01 g/l to 50 g/l, preferably about 0.02 g/l to 2 g/l at 111 degrees. It may be added by dissolving it in water or a hydrophilic solvent such as methanol, and if necessary, it can be used in combination with other known surfactants.

The types of photosensitive silver emulsions used in the present invention include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloride iodine, which are generally used in silver photosensitive materials. It is selected from silver bromide, silver bromoiodide, and mixtures of two or more thereof. 1. The type of emulsion may be either a negative emulsion or a positive emulsion, and for example, the surface of the photosensitive silver nologonide is made to be more easily soluble than the silver nologonide with a refractory agent. It may also be a special emulsion of the type described in JP-A-54-48544, which is comprised of substantially non-photosensitive metal salt particles that have been rendered insoluble.

These silver halide emulsions can be chemically sensitized using sulfur sensitizers, selenium sensitizers, noble metal sensitizers, reduction sensitizers, polyalkylene oxide sensitizers, etc. as necessary. It is felt. Further, if necessary, various sensitizing dyes may be used for spectral sensitization, and fogging may be prevented by using known stabilizers such as imidazoles, triazoles, and azaindenes.

Furthermore, if necessary, hardeners, antistatic agents, antioxidants,
Preservatives, dyes, matting agents, development rate regulators, graininess improvers, surfactants, thickeners, ultraviolet absorbers, etc. can be used.

As the silver halide binder, commonly used binders can be used, such as gelatin, gelatin derivatives, polyvinyl alcohol, copolymers of maleic anhydride and vinyl compounds, and ester compounds thereof.

The physical development nuclei in the physical development nucleus layer of the present invention include those used in the known silver salt diffusion transfer method, such as gold, chain rings, etc.
A metal sulfide or selenide obtained by mixing a metal colloid, a water-soluble salt such as silver, palladium, or zinc with a sulfide or selenide can be used.

For methods of producing physical development nuclei, see W, F, for example.

Be1g Edition Photographic Silver Halide Diffusion E-Processes (Photographic
Silver Halide Diffusion P
rocesses) 1972, Focal Pres.
s can be referred to.

In addition, the binder used in the physical development nucleus layer in the present invention includes gelatin, polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone, polyacrylate, casein, a copolymer of maleic anhydride and an ethylenically unsaturated organic monomer, and a copolymer of maleic anhydride with an ethylenically unsaturated organic monomer. A reaction product of a copolymer and an organic compound having an alcoholic hydroxyl group (saponified polyvinyl alcohol is particularly preferred) can be used alone or in combination.

Supports for the lithographic printing plate in the present invention include, for example, baryta paper, polyethylene-coated paper, polypropylene composite FM, paper, glass plate, polyester film such as cellulose aceterephthalate, which has been subjected to corona discharge treatment, subbing treatment, etc. Included are polyamide films, polypropylene films, polycarbonate films, polystyrene films, and metal plates such as anodized aluminum plates.

The means for making the hydrophilic material such as the corona discharge treatment, undercoating treatment, and anodizing treatment are silver halide photographic light-sensitive materials.
Known means for the 8th edition etc. can be applied.

These supports can be transparent or opaque depending on the purpose of the material. It can also be colored and made transparent with dyes, pigments, etc.

The opaque support is typically paper, but it also includes paper made light-shielding with carbon black, dyes, pigments, etc., and plastic films.

Further, the back surface of the support can be roughened with a matting agent to make it difficult to wash.

The layers constituting the lithographic printing plate of the present invention can be coated on the above-mentioned support by any coating method well known in the art. Examples include the evaporation method, the dip method, the air knife method, and the extrusion doctor method. Particularly preferred is the one-to-coating method described in US Pat. No. 2,761,791.

A silver halide developing agent is incorporated in the constituent layers of the lithographic printing plate of the present invention. In this case, development after exposure is
Activation treatment using an alkaline aqueous solution becomes possible.

The developing agent can be contained in the silver halide photosensitive layer or its adjacent layers (undercoat layer, interlayer or antihalation layer, release layer), etc. Incidentally, a developer may naturally be included in the alkali activation bath.

Specific compounds for the developer include polyhydroxyhensens, such as hydroquinone, catechol, chlorohydroquinone, hyrogallol, bromohydroquinone, inpropylhydroquinone, toluhydroquinone, methylhydroquinone, 2.3-dichlorohydroquinone, 2. 5-
Dimethylhydroquinone, Z3-dibromohydroquinone, 1,4-dihydroxy-2-acetophenone, 2.
5-dimethylhydroquinone, 4-phenylcatefur,
Includes 4-t-butylcatechol, 4-n-butylpyrogallol, '4,5-dibromocatechol, z5-diethylhydroquinone, 2,5-benzoylaminohydroquinone, 4-benzyloxycatechol, 4-n-butoxycatechol, etc. be done.

Among these, hydroquinone and methylhydroquinone are particularly preferably used.

Other developing agents include 3-pyrazolidone compounds such as 1-7 enyl-3-pyrazolidone, 1-p
-Tolyl-3-pyrazolidone, ■-phenyl-4-methyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-p-chlorophenyl-3-
Pyrazolidone, -p-methoxyphenyl-3-pyrazolidone, 1-phenyl-2-acetel-3-pyrazolidone, 1-7enyl-5.5-dimethyl-3-pyrazolidone, 1-o-chlorophenyl-4-methyl-4- Ether-3-pyrazolidone, l-m-acetamidophenyl-4
, 4-diethyl-3-pyrazolidone, 1.5-diphenyl-3-pyrazolidone, 1-(m-tolyl)-5-phenyl-3-pyrazolidone, 4.4-dihydroxymethyl-1-phenyl-3-pyrazolidone, 4.4-dihydroxymethyl-1-tolyl-3-pyrazolidone, 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone, 4-hydroxymethyl-4-methyl-1-(
p-chlorophenyl)-3-pyrazolidone and the like.

Examples of aminophenols include 1)-(methylamino)phenol, p-aminophenol, and Z4-
Examples include sifuminophenol, p-(benzylamino)phenol, 2-methyl-4-aminophenol, and 2-hydroxymethyl-4-aminophenol.

The above developing agents can be used alone or in combination. In particular, although the combination of a polyhydroxybenzene compound and a 3-pyrazolidone compound is not preferred, In?
In general, the amount may be in the range of 0.001 g to 1 g, and in the case of a silver halide photosensitive layer, it is used in the range of 0.01 g to 3 g/g of silver halide.

In the constituent layers of the present invention, if necessary, a compound called a complexing agent that tends to form a soluble silver complex salt with silver halide in the unexposed area can be included to advantageously promote physical development. .

Examples of complexing agents include thiosulfates, thiocyanates, amine thiosulfates as described in U.S. Pat. No. 3,169,962, or U.S. Pat.
, 857,276, mercapto compounds described in Japanese Patent Publication No. 11957/1980, and the like.

The above-mentioned developing agents may be added to the coating solution after being dissolved in water or a hydrophilic solvent such as methanol, or dissolved in a high-boiling point organic solvent or a low-boiling point organic solvent. High boiling point organic solvents generally have a boiling point of about 180
C or higher, such as alkyl esters of phthalic acid such as ethyl 7-thalerate and n-butyl phthalate, or phosphoric acid esters such as tricresyl phosphate. In addition, as a low boiling point organic solvent, generally about 30℃~1
Those having a boiling point of 50C include, for example, lower alkyl acetates such as ethyl acetate and butyl acetate.

Further, these high and low boiling point solvents may be used in combination, and the dissolved developing agent may be dispersed in the hydrophilic colloid of the constituent layer by any known method.

When added to the constituent layers of the lithographic printing plate in the present invention, it can be added directly to any layer or dissolved and added to gelatin or a synthetic polymer compound (e.g. polyvinyl alcohol, polyvinylpyrrolidone, US Pat.
, 488,708) and then applied.

The lithographic printing plate described above is developed in an alkaline activation bath containing an alkaline agent (for example, an alkali metal or ammonium hydroxide, carbonate, or phosphate).

The alkaline activation bath contains a silver halide solvent and a compound represented by the general formula [T', ). Further, if necessary, a development accelerator, an antifoggant, a stain or sludge inhibitor, a preservative, a metal sequestrant, a wetting agent, etc. can be contained.

Further, when it is necessary to stop the development (8) of the lithographic printing plate described above after development, a neutralizing solution can be used.

This neutralizing solution can be used in a normal acid stop bath, with a pH of approximately 3.0.
It may be adjusted to 8.0. This neutralizing liquid may contain a water softener, a pI (regulating agent, a relaxant, a hardening agent, etc.), and for the purpose of eliminating ink stains on the printing plate to be processed, colloidal silica, Alternatively, polyols and the like may be added or contained.

In the present invention, after the plate is obtained by processing as described above, various post-treatments can be performed for the purpose of improving printability. For example, for the purpose of improving ink adhesion,
U.S. Patent No. 3,592,647, U.S. Patent No. 3.490,9
No. 06, same No. 3,161,508 Meirō subscript, Special Publication 1977
-10910, 48-29723, 51-15
No. 762 and the method described in Japanese Patent Publication No. 52-15762.

For the purpose of eliminating ink stains on printed matter, for example, U.S. Pat.
No. 114, No. 4 (No. 1-763, No. 47-16946, No. 47-25242, No. 54-26921, No. 5)
The method described in Japanese Patent No. 4-33164 can be applied.

Furthermore, for the purpose of correcting the edges of printing prints, methods described in, for example, %-Kokai No. 48-41808, No. 51-21901 and No. 51-219014 can be applied.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 A gelatin solution containing the following as a developer and in which carbon black was dispersed was applied onto polyethylene coated paper subjected to corona discharge.

Developer [Amount added per mole of silver halide, the same applies hereinafter. ] Next, an orne-sensitized silver chlorobromide gelatin emulsion containing formalin as a hardening agent, Thyloid 308 manufactured by Fuji Devun Co., Ltd. as a matting agent, and a known surfactant was coated. The silver halide composition of this emulsion was 80 moles of silver chloride and the remainder was silver bromide, with a composition of 1rr? The silver was coated in an amount of 1.0 g and the gelatin was coated in an amount of 1.1 g.

Next, a gold colloid solution was applied to create a printing plate using a silver salt diffusion transfer method.

The sample obtained in this way was exposed to light, and the following 1: "A"
, ], [832 kinds of alkaline activation solutions were used for 30 seconds at 30°C, and then an acidic neutralizing solution was used for 30 seconds at 30°C. (A) is a sample of the present invention, and [B] is a sample of a comparative example.

Alkaline Activating Solution [A] [33] Next, after sensitizing with an etching solution, printing was carried out using an offset printing machine equipped with a device for supplying a dampening solution.

The resulting printability is as shown in Table 1 below, and the printing evaluation in the table was determined by the following method.

Printing durability: Evaluated by the number of continuously printed printed matter that became unprintable due to a decrease in density on both edges, image blurring, so-called blurring, or staining.

◎: 5000 sheets or more ○: 3500 sheets to less than 5000 sheets Δ: 1000 sheets to less than 3500 sheets The evaluation was based on the number of prints until a good printed matter was obtained.

Less than 0210 pieces △: More than 10 pieces and less than 50 pieces X: Printed matter with high density cannot be obtained.

Background staining: Evaluation was made from the stain density in the white background area after the 500th printed sheet.

○: No soiling occurs at all. stomach.

Δ:N, which is partially generated. Ru.

X: Highly concentrated dirt appears on the entire surface. live.

As is clear from Table 1, the printing characteristics of the present invention using the alkaline activating liquid [A]' are superior to those of the comparative example using the alkaline activating liquid [B].

Example-2 A gelatin solution in which carbon black was dispersed was applied onto a 180 μm thick subbed polyester film base,
Next, a silver chlorobromide gelatin emulsion and a gold colloid solution similar to those in Example 1 containing the following as a developer were coated to prepare a sample.

20.0 g of developer The sample thus obtained was statically developed at 30°C for 30 seconds using the following alkaline activating solution, and then printed in the same manner as in Example-1. .

Alkaline Activation Solution 0.1 g of each of the exemplified compound of the present invention and the following comparative compound are added to the above prepared solution, and the total amount is made up to 1 ton with water.

The obtained printing characteristics are as shown in Table 2 below, and the printing evaluation in the table was determined by the same method as in Example-1.

As is clear from Table 2, the printing characteristics when using the alkaline activating liquid of the present invention are superior to those of the comparative example.

Table 2 Comparative Compound-1 - Comparative Compound-2 ■Example-3 A lithographic printing plate was prepared in exactly the same manner as in Example-1 except that the developer was removed from the carbon black coating solution.
Development was carried out at 30° C. for 30 seconds using the following developer using a static development method and an agitation development method in which stirring is performed once every 2 seconds, and then processed in the same manner as in Example-1.

When the sample obtained by the developer stationary development method was printed in the same manner as in Example-1, a printed matter with high density and good quality from the beginning and with less staining was obtained, but the sample obtained by the stirring development method was The sample had severe unevenness due to processing, and clear prints could not be obtained.

In addition, using the same lithographic printing plate as in Example-1, Example-
When treated with the alkaline activation solution [A] of No. 1 in the same manner as above, the sample obtained by the static development method and the agitated development method No. 1 were treated in the same manner as above.
No difference was found in the printing properties between the samples obtained by the conventional method, and a large number of good prints were obtained by both methods.

Example 4 In this example, the method of the present invention was applied to a negative printing plate.

A palladium colloid solution hardened with formaldehyde containing polyacryland and polyvinyl alcohol as a binder was spread on a corona-discharged polyethylene coated paper and dried.

Next, the chemically sensitized silver iodobromide gelatin emulsion (silver iodide 6 molar width) prepared by a conventional method and the pure silver chloride emulsion also prepared by a conventional method were subjected to a sensitization method. Without straining, 1.9 g of 1-phenyl-5-mercaptotetrazole was added per mole of scissors chloride, and then both emulsions were mixed in a silver amount of 1.
:5 to obtain an emulsion, and the same developing agent as in Example-1 was added to the resulting emulsion to prepare a coating solution, which was then coated on the physical development nucleus layer and dried. .

The above configuration is based on a negative image forming method based on the method described in Japanese Patent Laid-Open No. 54-48544.

Obtained sample fj! : After exposure, using the alkaline activation liquid [A]= of Example-1, processing in the same manner as in Example-1, and printing with an offset printing machine, the results showed ink adhesion, resistance to ink, and rigidity. Printed matter with excellent surface staining was obtained.

〔Effect of the invention〕

As is clear from the above examples, according to the present invention, a lithographic printing plate having excellent printing durability and ink receptivity, and excellent printing characteristics without soiling can be provided.

Patent applicant: Konishiroku Photo Industry Co., Ltd., agent patent attorney
Nobuaki Sakaguchi (and 1 other person) Procedural amendment (self-insurance) February 7, 1981 Director General of the Patent Office Wakasugi η1o Representation of case 16 1981 Special Patent Application No. 5I < 1192 No. 3 Person making amendment Relationship with Patent Issuer 4, Agent 〒105 6 Number of Inventions Increased by Amendment Contents of Amendment (Machibi 1 1982-1192) The description will be amended as follows.

1 On the bottom line of page 6, “and IN, 0 is 01-C,”
The statement "and It, is a hydrogen atom, Cl-C19" is corrected.

2. In the 1st, 2nd and 3rd lines of page 7, the word "mouse" is corrected to "l"CnJ.

3 Add the following next to [Exemplary Compounds] (11) on page 8.

(1'1)CnH3■ +1r1. ,! 4 In the second to last line from the bottom of the same page, U Among these...
It is... "The most preferable ones among these are (x), (+>)-(3), (t2+, (+
3) and ([5) of the exemplary compound belonging to general formula (1)
, (+5) - (7) , (+4) There is. Correct it with J.

5 On page 20, lines 1-2, “[Silver halide...]
same. ]" r C100m, "+ Reno'aYf
5(;EI J.

that's all

Claims (1)

[Scope of Claims] A method for producing planographic printing applying a silver salt diffusion transfer method in which a constituent layer contains a developing agent (i) capable of developing exposed silver halide in an alkali activation bath, 1. A method for producing a lithographic printing plate, wherein the chemical bath contains a silver halide solvent and at least one compound represented by the following general formula [■]. [In the formula, 2 is a group of nonmetallic atoms necessary to complete a substituted or unsubstituted 5- to 6-membered heterocycle, and the heterocycle is a naazoline nucleus, a thiazole nucleus, a benzothiazole nucleus, an oxazoline nucleus, an oxazole nucleus, Benzoxazole nucleus, imidacilline nucleus, imidazole nucleus, benzimidazole nucleus, oxadiazole nucleus, thiadiazole nucleus, triazine nucleus,
selenazole nucleus, benzoselenazole nucleus, pyridine nucleus,
selected from pyrimidine and quinoline nuclei. ]