JPH02293750A - Positive type photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To improve developability and to allow the formation of sharp print- out images and the production and handling in safe working environment by incorporating either or both of the ether and ester of diethylene glycol at a prescribed ratio into a photosensitive layer. CONSTITUTION:Either or both of the ether and ester of the diethylene glycol are incorporated at 0.01 to 10wt.% of the weight of the photosensitive layer into the photosensitive layer. The above-mentioned ether and ester are preferably diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monoethyl ester monoacetate, and ethylene glycol monoacetate, etc. For example, dimethyl formamide, dimethyl sulfoxide, acetone, etc., may be incorporated at <=5wt.% as a suitable solvent in addition to the above-mentioned ether or ester into the photosensitive layer.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a positive-working photosensitive lithographic printing plate, and in detail,
The present invention relates to a positive-working photosensitive lithographic printing plate which has improved developability and printout images, and which can be manufactured and handled in an improved working environment.

[Background of the invention]

In general, a positive-working photosensitive lithographic printing plate (hereinafter also referred to as a photosensitive printing plate) is a positive-working photosensitive coating liquid (hereinafter also simply referred to as a coating liquid) prepared by dissolving a photosensitive composition in a suitable organic solvent. Conventionally, ethylene glycol alkyl ether and ethylene glycol alkyl ether acetate have been used as the organic solvent, and propylene glycol monoalkyl ether ( JP-A-61-6648) and propylene glycol alkyl ether acetate (JP-A-61-78)
No. 37) has also been proposed as the organic solvent.

However, when a photosensitive layer is formed using a coating solution in which an organic solvent as described above is used as a solvent for a photosensitive composition, the resulting photosensitive printing plate is difficult to form a clear printed image. In addition, the above-mentioned ethylene glycol alkyl ether and ethylene glycol alkyl ether acetate are highly toxic, so when producing photosensitive printing plates using a coating solution containing them, the working environment of the coating process is adversely affected and However, there was a problem in that the waste liquid produced was likely to cause pollution.

Therefore, the inventors of the present invention have conducted various studies in view of the above-mentioned circumstances, and have determined whether diethylene glycol ether or ester is included in the photosensitive layer of a photosensitive printing plate, based on the weight of this photosensitive layer. When one or both of them are contained in an amount of 00110% by weight, the developability of the photosensitive printing plate improves, the printed image obtained from the photosensitive printing plate becomes clearer, and the plate surface is less stained. Such a photosensitive printing plate is conveniently obtained by using one or both of the above-mentioned low toxicity ethers and esters of diethylene glycol as the organic solvent for preparing the coating solution; It has been found that the solvent improves the coating properties of the coating solution.

[Object and structure of the invention]

The present invention was invented based on the above knowledge, and is a positive type that has excellent developability, can form clear printed images, and can be manufactured and handled in a safe working environment. The purpose is to provide a photosensitive lithographic printing plate, and the photosensitive layer contains 0.01 to 10% by weight of diethylene glycol ether and/or ester, based on the weight of the photosensitive layer. This relates to a type photosensitive lithographic printing plate.

[Specific description of the invention]

The present invention will be explained in more detail below.

Ethers and esters of diethylene glycol used in the photosensitive layer of the present invention include diethylene glycol monomethyl ether, diethylene glycol 1,000 ethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monopentyl ether and diethylene glycol monophenyl ether. Monoalkyl- or -monoaryl ethers; diethylene glycol dialkyl- or -diaryl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol diprobyl ether, diethylene glycol dibutyl ether, diethylene glycol dipentyl ether and diethylene glycol diphenyl ether; diethylene glycol monomethyl ether mono Acetyl 1, Diethylene glycol monopropyl ether monoacetate, Diethylene glycol monopropyl ether monoacetate 1, Diethylene glycol monobutyl ether monoacetate, Diethylene glycol monopentyl ether monoacetate, Diethylene glycol monophenyl ether monoacetate, Diethylene glycol monopropyl ether monoacetate Diethylene glycol monoalkyl or monoaryl ether monoacetate such as acetate 1~: Examples include diethylene glycol monoacetate and diethylene glycol diacetate, and these organic solvents may be used alone or in combination of two or more types. I can do it.

Among the organic solvents listed above, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethyl glycol diethyl ether, diethylene glycol monomethyl ether monoacetate, diethylene glycol monoacetate, etc. are preferred, and diethylene glycol monoacetate is particularly preferred. Preference is given to dimethyl ether and diethylene glycol dimethyl ether.

The photosensitive printing plate of the present invention contains in the photosensitive layer 0.01 to 10%, preferably 0.01%, based on the weight of the photosensitive layer.
05 to 5% by weight, more preferably 0.1 to 2% by weight of any one or more of the diethylene glycol ethers and esters; In addition to the ester, the photolactic composition, and other additives added as necessary, it may contain some amount of a suitable organic solvent, for example, 5% by weight or less; such organic solvents include, for example, dimethylborumamide, dimethyl sulfoxide, acetone,
Diogysan, tetrahydrofuran, cyclohegisanone,
Methylene chloride, methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, diethyl ketone, cyclohexanol, n-butanol, benzyl alcohol,
Examples include phenethyl alcohol and water.

Note that if the content of diethylene glycol ether and/or ester in the photosensitive layer is less than 0.01% based on the weight of the photosensitive layer, the above-mentioned developability improvement effect and printout image may be impaired. However, if the content exceeds 10%, troubles such as the photosensitive layer becoming sticky and transfer to the mount etc. are likely to occur. The content of diethylene glycol ether and/or ester contained in the photosensitive layer was determined to be 0.01 to 10% by weight.

In order to contain diethylene glycol ether and/or ester in the photosensitive layer of a photosensitive printing plate, a coating solution containing one or more of these ethers and esters is applied to a support by a conventional method. The content of these ethers and esters can be adjusted by increasing or decreasing the amount (concentration) of the ethers and esters contained in the coating solution. be done.

The content of diethylene glycol ether and ester contained in the photosensitive layer is, for example, γ-butyrolactone,
The photosensitive layer is dissolved and peeled from the support using an organic solvent such as methanol or benzyl alcohol, the resulting solution is filtered, and the filtrate is subjected to, for example, gas chromatography mass spectrometry (C.C/MS). ”) and gas chromatography/Fourier transform infrared spectroscopy (
It can be detected and confirmed by analysis using GC/FT-IR method, etc.

Supports suitable for use in producing the photolactic lithographic printing plates of the present invention include aluminum, zinc,
Metal plates such as copper, metal plates coated with zinc, copper, chromium, etc., chrome-plated steel plates, paper and plastics treated to make them hydrophilic, paper and plastic films coated with metals, etc. , the most preferred is an aluminum plate. Particularly when the support is made of a metal plate such as an aluminum plate, it is preferable that the support is subjected to surface treatments such as graining, anodizing, and if necessary, sealing.

For the above-mentioned graining treatment, a technique that applies a roughening method such as brush polishing, ball polishing, chemical polishing, or electrolytic etching after degreasing the surface of a metal plate such as an aluminum plate should be adopted. I can do it.

The above-mentioned anodizing treatment is performed on a metal plate such as an aluminum plate in an aqueous or non-aqueous solution containing one or more of inorganic acids such as phosphoric acid, chromic acid, boric acid, and sulfuric acid, or organic acids such as oxalic acid and sulfamic acid. This is accomplished by passing an electric current through it as an anode.

Further, the above-mentioned sealing treatment is performed by immersing the metal plate in a hot aqueous solution containing an aqueous sodium silicate solution, hot water, and some inorganic or organic salts, or by exposing the metal plate to a steam bath.

As for the positive-working photosensitive composition used in the photosensitive layer of the photosensitive printing plate of the present invention, there is a difference in solubility in the developer between the exposed area and the unexposed area before and after exposure. Any material that forms a positive image can be used, and typical examples thereof include the following.

(1) Photolactic composition containing an 0-quinonediazide compound As an O-quinonediazide compound, for example, 0naf1.
Examples include ester compounds of quinonediazide sulfonic acid and polycondensation resins of phenols and aldehydes or ketones.

Examples of the phenols include phenol, 0-
Cresol, m-cresol, p-cresol, 3,5
- Monohydric phenols such as xylenol, carvacrol, and thymol; dihydric phenols such as catechol, resorcinol, and hydroquinone; and trihydric phenols such as pyrogallol and phloroglucin.

Examples of the aldehyde include formaldehyde, benzaldehyde-1-, ace-1-aldehyde, chloro-aldehyde, and furfural, and among these, formaldehyde and henzaldehyde are preferred.

Further, examples of the ketone include ace1-one and methylethylke1-one.

Specific examples of the polycondensation resin include phenol formaldehyde resin, m-cresol formaldehyde resin, rn~, p-mixed cresol formaldehyde resin, resorcinol henzaldehyde resin, and pyrogallol acetone resin.

The O-H
The condensation rate for groups (reaction rate for one OH group) is 15
-80% is preferable, and 20-45% is more preferable.

Furthermore, as the O-quinonediazide compound used in the present invention, compounds described in JP-A-58-43451 can also be used.

Among the above 0-quinonediaside compounds, 1.2henzoginonediazide sulfonyl chloride' or 12--1-
Most preferred is 0-quinonediazide ester obtained by reacting 1-co-1-nondiazide snoreboninolechloride with a pyrogallol acetone condensation resin or 23,4-1-lihyde IZ+xyhenzophenone.

As the O-quinonediazide compound used in the present invention, each of the above compounds may be used alone, or two or more types may be used in combination.

It is preferable to use these 0-quinonediazide compounds in combination with an alkali-soluble resin. Examples of the alkali-soluble resin include novolac resins, vinyl polymers having phenolic hydroxyl groups, and condensation resins of polyhydric phenols and aldehydes or ketones described in JP-A-55-57841.

Examples of the novolac resin include phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde copolycondensate resin as described in JP-A-55-57841, JP-A-55127553.
Examples include copolycondensate resins of p-substituted phenol and phenol or cresol and formaldehyde as described in the above publication.

In addition, the vinyl polymer having a phenolic hydroxyl group is a polymer having a unit having a phenolic hydroxyl group in its molecular structure, and at least one of the following general formulas (I) to (V). Polymers containing structural units are preferred.

General formula CI) General formula (II) General formula (1) General formula [■] 0H General formula (V) B OH [In the formula, R1 and R2 each represent a hydrogen atom, an alkyl group or a carboxyl group, preferably a hydrogen atom. represents,
R represents a hydrogen atom, a halogen atom or an alkyl group, preferably a hydrogen atom or an alkyl group such as a methyl group or an ethyl group; R4 represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, preferably a hydrogen atom; A connects a nitrogen atom or an oxygen atom and an aromatic carbon atom,
Represents an alkylene group that may have a substituent, m is 0
represents an integer of ~10, and B represents a phenylene group that may have a substituent or a naphthylene group that may have a substituent. ] Preferably, the above-mentioned polymer has a copolymer-type structure.《The monomer units that can be used in combination with the structural units represented by the general formulas (I) to (V) are as follows: For example, ethylenically unsaturated olefins such as ethylene, propylene, isobutylene, butadiene, and isoprene; styrenes such as styrene, α-methylstyrene, p-methylstyrene, and p-chlorostyrene; acrylic acids such as acrylic acid and methacrylic acid; ; Unsaturated aliphatic dicarboxylic acids such as itaconic acid, maleic acid, maleic anhydride; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, dichloroethyl acrylate, phenyl acrylate, Methyl α-chloroacrylate, Methyl meccrylate,
Esters of α-methylene aliphatic monocarboxylic acids such as ethyl methacrylate and ethyl ethacrylate; nitriles such as acrylonitrile and methacrylonitrile; amides such as acrylamide; acrylanilide, p-chloroacrylanilide, m-nitroacrylic Anilides such as anilide and m-methoxyacrylanilide; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl oxate; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, and β-chloroethyl vinyl ether. ; Vinyl chloride, vinylidene chloride, vinylidene cyanide, 1-methyl-
1-methoxyethylene, 1.1-dimethoxyethylene,
Ethylene derivatives such as 1,2-dimethoxyethylene, 1,1-dimethoxycarbonylethylene, 1-methyl-1-ditroethylene; N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinylpyrroli There are vinyl monomers such as N-vinyl compounds such as ten and N-vinylpyrodone. These vinyl monomers exist in polymer compounds with a structure in which unsaturated double bonds are cleaved.

Among the above monomers, esters of aliphatic monocarboxylic acids and nitrites are preferred.

Some of these photosensitive compositions may contain other ingredients as necessary.
Furthermore, pigments such as dyes or pigments, fattening agents, plasticizers, surfactants, organic acids, acid anhydrides, compounds capable of generating acids upon exposure to light, etc. can be added.

In order to apply the photosensitive coating liquid, generally known roll coaters, slide bopper one-way coaters, gravure coaters, boiler coaters, wire bar coaters, etc. can be used.

The drying conditions are preferably relatively low temperature in the initial stage and relatively high temperature in the latter half.
It is appropriate to hold the temperature at 70-110°C, preferably 75-90°C, for about 20-180 seconds.

Although the coating amount of the photosensitive composition varies depending on the application, a coating amount of 0.5 to 3.5 g/m 2 as solid content is generally appropriate.

〔Example〕

Next, the present invention will be explained in detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 0.24 mm thick in 5% aqueous sodium hydroxide solution
After degreasing an aluminum plate with a width of 1030 mm, it was heated in a 0.5 molar hydrochloric acid aqueous solution at a temperature of 25°C.
Electrolytic etching treatment was performed under the conditions of current density: 60 A/dm'' and treatment time: 30 seconds.Next, after desmutting treatment was performed with a 5% sodium hydroxide aqueous solution, anodization treatment was performed in a sulfuric acid solution. After that, it was immersed in a hot aqueous solution at 90°C for pore sealing treatment.

Next, a photosensitive coating solution having the following composition was applied to the aluminum plate support treated in this way using a roll coater at a coating speed of 10 m/min.
35°C, second half 25m 85”C, air volume 50r+{/
The plate was dried at 10 min to obtain a photolactic lithographic printing plate sample 1 of the present invention.

Composition of photosensitive coating liquid Pyrogallol acetone resin and naphthoquinone (1.2
) monodiazide-5-sulfonic acid chloryl ester compound (condensation rate of 1 OI group 30 mol% weight average molecular weight 2
500) 2.3 parts by weight of phenol and m-+p-mixed cresol (molar ratio 48:32:20)
and formaldehyde (weight average molecular weight 10,000) 6.7 parts by weight Novorasoc resin (weight average molecular 5f2,000) synthesized from roseoctylphenol and bomarin and naphthoquinone (L2)
Ester compound with monodiazide-5-sulfonic acid chloride (condensation rate of OH, 1: 50 mol%) 0.9 parts by weight 2-Trichloromedyru-5-(β-henzofuryl vinyl)-1.3.4- Oxadiazur: 0.05 parts by weight Victoria Pure Blue BOH: 0.07 parts by weight Diethylene glycol dimethyl ether: 27 parts by weight Methyl ethyl ketone iBmit The coating weight after drying was about 22 mg/dm2.

Next, the solvent in the coating solution was changed to the solvent shown in Table 1 below, and the drying conditions of the applied coating solution were changed to the conditions shown in Table 2 below. Inventive samples 2 to 8 and comparative samples 1 to 4 of photolactic printing plates were prepared in the same manner as inventive sample 1 above, and the amount of solvent remaining in the photosensitive layer of these samples was determined by the following method. The results are shown in Table 2.

Sample size: 10cm x 10cm without dissolving the photosensitive layer Solvent: Methanol = 10ml Gas chromatography method Equipment: 063 type gas chromatography (Hitachi) Column: PEG-20M Temperature: Injection...200°C
Column ・・・・・・・・・・・・ 150°C Detector ・・・・・・・・・・・・ 200”C detection...Hydrogen flame carrier gas...Helium quantitative method... Calculated from a separately prepared calibration curve (based on peak area) Table 1. The conditions of coating unevenness (marangoni) and vertical streaks that occur in the coating film of the above coating solution were observed, and the coating properties of those coating solutions were evaluated as follows. The evaluation was divided into three stages and the results are shown in Table 3.

A: B Good (Marangoni, no vertical streaks) B: Slightly inferior, but practical C: Poor, not practical Next, each of the above samples was exposed under the following exposure conditions, and the sharpness of the printed image produced was Visual evaluation was performed, and the results were divided into the following four levels and shown in Table 3.

◎: Clear O: Slightly clear △: Slightly unclear ×: Blurry Exposure conditions Exposure machine: Idolfin 2000 (2Kn metal halide lamp) 13mW/c exposure time: 92 seconds Film Original: Kodak Step Tablet No. 2 Halftone dot image and dot chart Next, each sample exposed as above was developed under the following development condition 1 under the number of steps shown in Table 3, and then developed under the following development condition 2. Using the resulting lithographic printing plates, we printed under the following printing conditions, observed the state of stains on each printing plate after printing, and divided the results into the following four stages. The results are shown in Table 3.

◎: No stains at all; Almost no stains △: Some stains ×: Considerable stains Development conditions 1 Developer: 6 times diluted solution of SDR-1 (manufactured by Konica Corporation) Development temperature: 27°C Development time: 20-second automatic developing machine: PSQ-910 (manufactured by Konica Corporation) Development conditions 2 Developer: A photosensitive printing plate exposed on the entire surface was fatigued by repeatedly developing with the developer used in development condition 1 above (mother solution Developing temperature: 27°C Development time: 20 seconds Automatic development m: PSQ-9 10 (manufactured by Konica Corporation) Printing conditions Printing machine: Heidel GTO Printing ink: Toyo Ink ( Co., Ltd. "Mark V" Printing paper: Coal, Paper Dampening water: Fresh water Printing speed: 700 sheets/hour Plankécil: Kinyo brush (hereinafter referred to as margin) From the results shown in Table 3, the present invention Samples 1 to 8 all produce clearer printed images overall than Comparative Samples 1 to 4, have photosensitive coatings (photosensitive layers) with improved coating properties, and are free from stains on the plate surface. It can be seen that it is possible to form a printing plate that is less likely to cause.

[Effects of the Invention] As is clear from the above explanation, the present invention G has excellent developability and can form a clear printout image, and can be manufactured in a safe working environment. Provided is a positive photosensitive lithographic printing plate that can be handled, has no coating unevenness or vertical streaks, and can form a lithographic printing plate that does not easily stain the plate surface.

Applicant Co., Ltd. Agent: Miki Nakajima, male and 1 other person 2'2

Claims (1)

[Claims] A positive photosensitive lithographic printing plate containing 0.01 to 10% by weight of either or both of diethylene glycol ether and ester in the photosensitive layer, based on the weight of the photosensitive layer.