JPH03255448A - Photosensitive coating solution - Google Patents

Abstract

PURPOSE:To reduce toxicity and foul odor, to improve the suitability of a photosensitive soln. to leveling and coating and to suppress the stain of the surface of a plate by incorporating ethylene glycol monoacetate and/or ethylene glycol diacetate as a coating solvent. CONSTITUTION:Ethylene glycol monoacetate and/or ethylene glycol diacetate is incorporated as a coating solvent. This ethylene glycol monoacetate and.or ethylene glycol diacetate may be mixed with other solvent. In this case, the ethylene glycol monoacetate and/or ethylene glycol diacetate is used by >=10 wt.%, preferably 20-80 wt.% of the total amt. Foul odor and toxicity are reduced and a photosensitive coating soln. having improved suitability to leveling and coating and suppressing the stain of the surface of a plate can be obtd.

Description

Detailed Description of the Invention [Field of Application in Industry A] The present invention relates to a photosensitive coating liquid, and more specifically, the present invention relates to a photosensitive coating liquid that has improved odor, low toxicity, improved leveling properties, especially coating properties, and improved printing surface. The present invention relates to a photosensitive coating liquid that can provide a lithographic printing plate free of diazo stains, particularly when a diazo resin is used as the diazo substance.

[Background of the Invention] A photosensitive lithographic printing plate is produced by dissolving a photosensitive composition in a suitable solvent, applying the solution to a support, and drying it. Conventionally, such a photosensitive lithographic printing plate During the production of
Various solvents are used to dissolve the photosensitive composition, such as methyl cellosolve (ethylene glycol monomethyl ether), ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and ethylene glycol monomethyl ether acetate.

However, although these coating solvents have good material solubility, they have a problem in that they are highly toxic during the production of photosensitive printing plates, and they also have a strong odor and are unpleasant, making them unfavorable in terms of the working environment. Furthermore, when a photosensitive composition is coated onto a support using the above-mentioned solvent, leveling properties (particularly coating properties) are poor, and coating irregularities such as streaks and pinholes often occur, impairing the product's value. This has become a problem.

Furthermore, these solvents are undesirable because they cause staining of the plate surface, and in particular, when the photosensitive layer for the lithographic printing plate is made of a diazo resin, they cause the generation of diazo residue.

- Japanese Patent Application Laid-open No. 61-6648 discloses that a brobylene glycol compound is used as a solvent for a photosensitive coating solution.
It is described in JP-A-62-14652, etc., and the photosensitive coating liquid obtained using this propylene glycol-based compound has considerably improved toxicity, odor, and coating properties, but it has problems such as staining of the printing plate, especially This is not preferable because it causes the problem of diazo residue and has poor leveling properties. Therefore, improvements in these points are desired.

Therefore, the inventors of the present invention have conducted various studies regarding the above-mentioned problems, and have discovered that the problems with photosensitive liquids can be improved by using a certain type of organic solvent, and have hereby completed the present invention. reached.

[Objective of the Invention] The object of the present invention is to improve odor, reduce toxicity, and improve leveling and coating properties, as well as improve plate surface stains and diazo residue when diazo resin is used as the diazo substance. An object of the present invention is to provide a photosensitive coating liquid containing an excellent coating solvent.

[Structure of the Invention] The above object of the present invention is distantly related to a photosensitive coating liquid characterized by containing ethylene glycol monoacetate and/or ethylene glycol diacetate as a coating solvent.

The present invention will be explained in more detail below.

The photosensitive coating liquid used in the present invention includes, as a coating solvent,
Contains ethylene glycol monoacetate and/or ethylene glycol diacetate, which improves toxicity and odor, and improves the leveling and coating properties of the photosensitive coating solution in the coating process of the photosensitive coating solution. In addition, plate surface stains, especially diazo residue, are improved.

Ethylene glycol monoacetate or ethylene glycol diacetate used in the present invention may be used alone or in combination.

In this case, ethylene glycol monoacetate or ethylene glycol diacetate is preferably used in an amount of 10% by weight or more, preferably 20% by weight to 80% by weight.

Furthermore, other solvents may be mixed. One or more types of other solvents can be used in combination.

Other solvents include methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butanol, 5ec-butanol, isobutanol, 7-butanol, 1-pentanol, 2-pentanol, 1-hexanol, etc. alcohol, acetone,
Methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, methyl-n-butyl ketone,
Ketones such as methyl isobutyl ketone, cyclopentanone, cyclohexanone, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether,
Diethylene glycols such as diethylene glycol monoethyl ether, diethylene glycol isopropyl ether, diethylene glycol monophenyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, ethyl acetate,
Acetate esters such as n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, n-hexyl acetate, other water, methyl lactate, ethyl lactate, propyl lactate, Diethyl ether, dioxane, dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, 3-methoxy-
Examples include 1-butanol, 3-methyl-3-methoxy-1-butanol, tetrahydrofuran, methylene chloride, and the like. Among these, the diethylene glycols, lactic acid esters, γ-butyrolactone, 3-methoxy-1-butanol and 3-methyl-3-methoxy-1-butanol are preferably used.

In particular, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, methyl lactate, ethyl lactate, and 3-methoxy-1-butanol have low toxicity, mild odor, appropriate boiling point, and appropriate drying load. It is particularly preferably used because it provides an excellent appearance of the coated product.

The coating solution obtained by dissolving in the solvent used in the present invention can contain either a positive-working photosensitive composition or a negative-working photosensitive composition, but as this positive-working photosensitive composition, , a polymer compound containing an orthoquinonediazide group is mainly used. Here, the polymer compound containing an orthoquinonediazide group refers to a reaction product of a compound containing an orthoquinonediazide group and an alkali-soluble resin, or a polymer compound containing an orthoquinonediazide group. It is used to mean either or both of the cases where it is a mixture of the compound containing the compound and the alkali-soluble resin.

Typical examples will be explained below.

As a polymer compound containing an orthoquinonediazide group,
For example, ester compounds of 0-naphthoquinonediazide sulfonic acid and polycondensation resins of phenols and aldehydes or ketones may be mentioned.

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

Examples of the aldehyde include formaldehyde, benzaldehyde, acetaldehyde, crotonaldehyde,
Examples include furfural.

Preferred among these aldehydes are formaldehyde and benzaldehyde.

Furthermore, examples of the above-mentioned ketones include acetone, methyl ethyl ketone, and the like.

Specific examples of the polycondensation resin include phenol/formaldehyde resin, Peng-cresol/formaldehyde resin, m-, o-mixed cresol/formaldehyde resin, resorcinol/benzaldehyde resin, pyrogallol/acetone resin, and the like.

The condensation rate of 0-naphthoquinonediazide sulfonic acid with respect to the O)I group of the phenol in the 0-naphthoquinonediazide compound (reaction rate with respect to one OH group) is 15 to 80.
%, more preferably 20 to 45%.

Further, 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-quinonediazide compounds, O-quinonediazide is obtained by reacting 1,2-benzoquinonediazide sulfonyl chloride or 1,2-naphthoquinonediazide sulfonyl chloride with pyrogallol acetone condensation resin or 2.3.4-trihydroxybenzophenone. Ester compounds are most preferred.

As the 0-quinonediazide compound used in the present invention, each of the above compounds may be used alone, or compounds having 2fi or more may be used in combination.

The polymer compound containing 0-quinonediazide used in the present invention preferably has a molecular weight of 1500 or more, more preferably 200°O or more, in view of coating properties.

The above-mentioned 0-quinonediazide compound is preferably used in combination with an alkali-soluble resin. Examples of alkali-soluble resins include novolac resins, vinyl polymers having phenolic hydroxyl groups, and condensed resins of polyhydric phenols and aldehydes or ketones described in JP-A-55-57841. Examples of the novolak resin include phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde copolycondensation resin as described in JP-A-55-578414, and phenol-cresol-formaldehyde copolycondensation resin as described in JP-A-55-127553. Examples include copolycondensation resins of P-substituted phenol and phenol, or of cresol and formaldehyde, as shown in the following.

Moreover, the vinyl polymer having a phenolic hydroxyl group is a polymer having a unit having the phenolic hydroxyl group in its molecular structure, and is a polymer having the following general formula [I] to -numerical formula [
Polymers containing at least one structural unit of V] are preferred.

- Formula [I] - Formula [II] General formula [III] General formula [IV] General formula [V] H [wherein R and R2 each represent a hydrogen atom, an alkyl group, or a carboxyl group, preferably a hydrogen atom ,R
5 represents a hydrogen atom, a halogen atom or an alkyl group,
Preferably, it represents 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 represents an alkylene group optionally having a substituent that connects a nitrogen atom or an oxygen atom and an aromatic carbon atom, m represents an integer of O to 10, and B has a substituent. represents a phenylene group that may have a substituent or a naphthylene group that may have a substituent. ] The polymer used in the photosensitive composition of the present invention preferably has a copolymer-type structure, and can be used in combination with the structural units represented by formulas [I] to [V] above. Examples of monomer units that can be used include ethylenically unsaturated olefins such as ethylene, propylene, isobutylene, butadiene, and isoprene, such as styrene, α-methylstyrene, p-
Styrenes such as methylstyrene and p-chlorostyrene,
For example, acrylic acids such as acrylic acid and methacrylic acid,
For example, unsaturated aliphatic dicarboxylic acids such as itaconic acid, maleic acid, maleic anhydride, etc., such as methyl acrylate,
Ethyl acrylate, 〇-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2-acrylate
Esters of α-methylene aliphatic monocarboxylic acids such as chloroethyl, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, and ethyl ethacrylate; nitriles such as acrylonitrile and methacrylonitrile; Amides such as acrylanilide, p-chloroatarylanilide, m-nitroacrylanilide, -methoxyacrylanilide, etc., such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, etc. Vinyl esters, such as methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, β-chloroethyl vinyl ether, vinyl chloride, vinylidene chloride, vinylidene cyanide, such as 1-methyl-1-methoxyethylene,
Ethylene derivatives such as 1,1-dimethoxyethylene, 1,2-dimethoxyethylene, 1,1-dimethoxycarbonylethylene, 1-methyl-1-ditroethylene, such as N-vinylpyrol, N-vinylcarbazole, N-
There are N-vinyl polymers such as vinyl indole, N-vinylpyrrolidone, and N-vinylpyrrolidone. These vinyl-based caramers exist in polymer compounds with a structure in which unsaturated double bonds are cleaved.

Among the above monomers, aliphatic monocarboxylic acid esters and nitriles exhibit excellent performance for the purpose of the present invention and are therefore preferred.

Considering the applicability of these alkali-soluble resins,
Those having a molecular weight of 1,500 or more are preferable, and those having a molecular weight of 2,000 or more are more preferable.

In addition to the above-mentioned materials, these photosensitive compositions may also contain colorants such as dyes and pigments, sensitizing agents, plasticizers, surfactants, organic acids, acid anhydrides, and acids that can be removed by exposure to light. Compounds that may be generated can be added.

There are various types of negative photosensitive materials used in the present invention, and representative ones will be described below.

(1) Photosensitive composition containing diazo resin The diazo resin represented by the condensate of p-diazodiphenylamine and formaldehyde may be water-soluble or water-insoluble, but is preferably
7 and No. 57-43890, etc., which are water-insoluble and soluble in ordinary organic solvents are used. Particularly preferred is a diazo resin represented by the following general formula [1].

General Formula [I] [In the formula, RI R2 and R3 represent a hydrogen atom, an alkyl group, or an alkoxy group, and R4 represents a hydrogen atom, an alkyl group, or a phenyl group.

X represents PFe or BF4, Y represents -NH--5- or -〇-] The diazo resin is preferably used in combination with a film-forming resin, especially a lipophilic polymer compound having a hydroxyl group. . In addition to those listed above, such lipophilic polymer compounds include monomers having an aliphatic hydroxyl group in the side chain, such as 2
Copolymers of -hydroxyethyl acrylate or 2-hydroxyethyl methacrylate and other copolymerizable monomers can be mentioned. In addition to these, polyvinyl butyral resins, polyurethane resins, polyamide resins, epoxy resins, novolak resins, natural resins, etc. may be added as necessary.

Various polymeric compounds can be used as the binder used in combination with the diazonium salt, but preferably, JP-A-54-9
Monomers having an aromatic hydroxyl group as described in Japanese Patent No. 8613, such as N-(4-hydroxyphenyl)acrylamide, N-(4-hydroxyphenyl)methacrylamide, o-, m+, or p- Copolymers of hydroxystyrene, o+, m-, or p-hydroxyphenyl methacrylate and other monomers, hydroxyethyl acrylate units as described in U.S. Pat. No. 4,123,276, or Polymers containing hydroxyethyl methacrylate units as the main repeating unit Natural resins such as shellac and rosin, polyvinyl alcohol, polyamide resins described in U.S. Patent No. 3,751,257, U.S. Patent No. 3,66
0.097, a phthalated polyvinyl alcohol resin, an epoxy resin condensed from bisphenol A and epichlorohydrin, and celluloses such as cellulose acetate and cellulose acetate phthalate.

Examples of the alkali-soluble resin include novolac resin, vinyl polymer having a phenolic hydroxyl group, and JP-A-55-5
Examples include condensation resins of polyhydric phenols and aldehydes or ketones described in Japanese Patent No. 7841. Examples of novolac resins include phenol/formaldehyde resin, cresol/formaldehyde resin, and JP-A-5
Phenol-cresol-formaldehyde copolycondensation resin as described in JP-A No. 5-57841, p as described in JP-A-55-127553
Examples include copolycondensation resins of -substituted phenol and phenol or cresol and formaldehyde.

In addition to the above-mentioned materials, these photosensitive compositions may also contain colorants such as dyes and pigments, sensitizing agents, plasticizers, surfactants, organic acids, acid anhydrides, and acids that can be removed by exposure to light. Compounds that may be generated can be added.

These binders are present in the solid content of the photosensitive composition in an amount of 40 to 99%.
It is contained in an amount of 50 to 95% by weight. Also, diazo resin has a rating of 1 to 60! ! It is contained in an amount of %, preferably 3 to 30% by weight.

Other dyes, pigments such as pigments, fat-sensitizing agents, plasticizers, surfactants, etc. can be added to these photosensitive compositions.

0 1 (2) A photosensitive composition containing a polymer compound having a -C-C)l-C- group in the main chain or side chain of the polymer. Or those whose main component is a photosensitive polymer such as polyesters, polyamides, and polycarbonates containing -C-CH-C- as a photosensitive group in the side chain (for example, U.S. Patent 'ftl 3,030,208, Same No. 3,707.37
Compounds such as those described in No. 3 and No. 3,453,237); photosensitive polyesters derived from (2-probelidene) malonic acid compounds such as cinnamylidene malonic acid and difunctional glycols; (e.g., U.S. Patent Nos. 2,956,878 and 3)
173.787); cinnamate esters of hydroxyl-containing polymers such as polyvinyl alcohol, starch, cellulose and the like (e.g. No. 966, No. 2
, 752,372, 2.732,301, etc.).

These photosensitive compositions may contain other sensitizers, stabilizers, plasticizers, pigments, dyes, and the like.

(3) Photopolymerizable composition comprising an addition polymerizable unsaturated compound This composition preferably comprises (a) a vinyl monomer having at least two terminal vinyl groups, (b) a photopolymerization initiator, and ( C) Consists of a polymer compound as a binder.

The vinyl monomer of this component (a) is
No. 5093, No. 35-14719, No. 44-2872
It is described in each publication No. 7.

Acrylic or methacrylic acid esters of polyols, such as diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, or methylene bis(meth)acrylamide , bis(meth)acrylamides such as ethylene bis(meth)acrylamide, or unsaturated monomers containing urethane groups, such as di(2'-methacryloxyethyl)-2,4-tolylene diurethane, di( Diol mono(meth) such as 2-acryloxyethyl) trimethylene diurethane etc.
Examples include reaction products of acrylate and diisocyanate.

As the photopolymerization initiator of component (b), the compound represented by the general formula [I] can be used, but other types can also be used. For example, carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo and diazo compounds, as described in Chapter 5 of "Light Sensitive Systems" by J. Kosar, cited above;
These include halogen compounds and photoreducible dyes. More specifically, it is disclosed in British Patent No. 1,459,563.

Furthermore, various known polymers can be used as the binder for component (C). Details of specific binders are described in US Pat. No. 4,072,527.

These photopolymerizable compositions contain thermal polymerization inhibitors, plasticizers,
It can contain dyes, pigments, etc.

(4) Photosensitive composition containing an azide group As the photosensitive azide compound, an aromatic azide compound in which the azide group is bonded to an aromatic ring directly or via a carbonyl group or a sulfonyl group is preferably used.

For example, polyazidostyrene, polyvinyl-p as described in U.S. Pat. No. 3,096,311;
-Azidobenzoate, polyvinyl-p-azidobenzal, reaction product of azidoarylsulfonyl chloride and unsaturated hydrocarbon polymer described in Japanese Patent Publication No. 45-9613, and Japanese Patent Publication No. 43-21017, 44
No.-229, No. 44-22954, No. 45-2491
Polymers having sulfonyl azide or carbonyl azide as described in each publication of No. 5 can be mentioned.

A liposensitizing agent and a surfactant added to the photosensitive composition,
The amount of additives such as sensitizers, stabilizers, thermal polymerization inhibitors, plasticizers, and pigments such as dyes and pigments varies depending on the type, but in general, they are included in the photosensitive composition contained in the photosensitive coating liquid. 0.01 to 20% by weight, preferably 0.05 to 20% by weight based on the product
10% by weight is suitable.

Dyes preferably used in the present invention include basic dyes and oil-soluble dyes. Specifically, Victoria Pure Blue BOH, Victoria Blue BH, Methyl Violet, Eisen Malachite Green (manufactured by Hodogaya Chemical Industry), Patent Pure Blue
Basic dyes such as vX, Rhodamine B, Methylene Blue (manufactured by Sumitomo Chemical), Sudan Blue II, Victoria Blue F1a (B.

A, S, F), oil blue #603, oil
Oil-soluble dyes such as Blue BO3 and Oil Blue IIN (manufactured by Orient Chemical Industries) are exemplified.

Various types of supports can be used for manufacturing photosensitive printing plates by applying the photosensitive coating liquid of the present invention, and examples include metal plates such as aluminum, zinc, copper, and steel, and chrome plates. , metal plates plated or vapor-deposited with zinc, copper, nickel, aluminum, etc., paper and plastics treated to make them hydrophilic, paper and plastic films coated with metals, glass plates, resin-coated paper, metal foils such as aluminum, etc. For example, paper covered with

Among these, aluminum plates are preferred.

Particularly in the case of aluminum plate supports, graining IA
It is preferable that surface treatment such as anodic oxidation treatment, sealing treatment, etc., be performed as necessary.

As a method for the above-mentioned graining treatment, commonly used techniques such as brush polishing, ball polishing, chemical polishing, electrolytic etching, etc. are employed after degreasing the surface of the aluminum plate or the like.

The above anodic oxidation treatment is performed using, for example, phosphoric acid, chromic acid, boric acid,
This is carried out by passing an electric current through an aluminum plate or the like as an anode in an aqueous or non-aqueous solution of an inorganic salt such as sulfuric acid, or an organic acid such as oxalic acid or sulfamic acid, or a mixture of two or more of these acids.

Furthermore, the sealing IA filling is carried out by immersion in a hot aqueous solution of a sodium silicate aqueous solution, a mineral salt, and some inorganic or organic salts, or by a steam bath.

In the present invention, the amount of photosensitive coating liquid applied to the support is as follows:
Depending on the use, - numerically 0.5 to 3 as solid content
．． 5g/■2 is appropriate.

The coating method of the present invention includes dip coating, roll coating, reverse roll coating, air doctor coating, blade coating, front coating, knife coating, squeeze coating, gravure coating, cast coating, curtain coach ink, A method such as extrusion coating is used, and the coating thickness is 0.1 to 5 g/m.
The drying temperature is preferably in the range of 20 to 150°C, preferably 30 to 100°C.

[Examples] The present invention will be explained below using Examples, but the present invention is not limited thereto.

Example 1 [Preparation of photosensitive lithographic printing plate] An aluminum plate with a thickness of 0.24 m++ was degreased in a 5 wt% aqueous sodium hydroxide solution at 60°C for 1 minute, and then treated with 0.5 molar hydrochloric acid. Electrolytic etching treatment was performed in an aqueous solution at a temperature of 25° C., a current density of 60 A/da”, and a treatment time of 30 seconds.

Then, in a 5 wt % sodium hydroxide aqueous solution at a temperature of 60
°C] After desmutting for 0 seconds, anodizing was performed in a 20% by weight sulfuric acid solution at a temperature of 20°C, a current density of 3A/dI11'', and a treatment time of 1 minute.
A hot water sealing treatment was performed with hot water at 0° C. for 20 seconds to produce an aluminum plate as a support for a lithographic printing plate material.

A photosensitive composition coating solution having the following composition was applied to the aluminum plate prepared as above using a roll coater, and dried at 90°C for 45 minutes to obtain a positive type photosensitive lithographic printing plate sample N011. .

Note that the amount of photosensitive composition was 24 B/da''.

[Coating liquid composition of photosensitive liquid] Binder (BD-1) 7.
0g Quinonediazide compound (QD-1) 1.6
g2-Trichloromethyl-5-(β-benzofurylvinyl)-1,3,4-oxadiazole 0.06g Novolac resin base-based from paraoctylphenol and formalin and 1,2-quinonediazide-5-sulfonic acid Ester compound with chloride (average molecular weight 2000
) 0.06g Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.06g
Ethylene glycol monoacetate 30g Diethylene glycol dimethyl ether 70g A photosensitive coating liquid sample was prepared in the same manner as Sample No. 011 except that the binder quinonediazide compound and coating solvent were changed as shown in Table 1 in the coating liquid composition of the above photosensitive composition. N092-9 was obtained.

Samples Nos. 1 to 9 thus obtained were coated on a grained aluminum plate, and the coatability of the samples was observed. Separately, the degree of recovery (leveling property) was investigated by forcibly scoring immediately after coating.Next, this sample was exposed and developed under the following exposure conditions to evaluate plate surface stains caused by printing.

[Mw of the resin before reacting with the compound QD-1 x/y-1/2 and Q + used in the photosensitive solution
=9001 QD-2 QD-5 x/y-1/2, M of resin before reacting Q2
w-9002 QD-3 H QD-1 Phenol and m-, p-mixed cresol (each molar ratio 4
8232:20) and formaldehyde Mw-1500D-4H of the resin before reacting with QD-2 CH3CL Q+ (k:j2:m:n-25+20:50:2, Mw=
60000) [Exposure conditions] A positive transparent original image is brought into close contact with the sample of a photosensitive lithographic printing plate,
Exposure was carried out from a distance of 90 cm using a 2Kvt metal halide lamp (Idolfin 2000 manufactured by Koji Denki Co., Ltd.) as a light source.

Mw of resin before reacting with Q2 = 1500 [Development conditions Developer solution: 0.1% sodium 4-benzenesulfonate added to 4% sodium metasilicate aqueous solution (does not contain organic molten blade) Automatic developing machine: Konica PS plate automatic developing machine rPSK-910J (manufactured by Konica) Development temperature = 27
℃ Development time: 20 seconds [Printing conditions Printing machine: Heidel GTO Printing ink: Toyo King New Bright Red (manufactured by Toyo Ink Co., Ltd., oil-based ink) Printing paper: High quality paper Printing speed: aooo sheets/hour and evaluation in Table 1 is as follows.

[Stain on the plate A: No stain on the plate B: Slight stain on the plate, but to the extent that it can withstand practical use C: Stain on the plate occurs, with a slight impact on practical use; 2. Stain on the plate is noticeable. [Coatability] Marangoni refers to hazy, swirl-like coating unevenness that occurs on the coated surface after coating and drying.

The cause of this type of coating unevenness is the Marangoni effect, which is caused by local differences in surface tension of the wet photosensitive layer due to a temperature drop accompanying the volatilization of the solvent.

A pinhole refers to a circular white spot in the photosensitive layer that appears on the coated surface. Further, vertical streaks are a state in which the thickness of the photosensitive layer is non-uniform, which appears in the running direction of the support because the coating solution is not smoothed.

Each item of coating property: A: Excellent B: Good C: Slightly poor D: Poor The results of the obtained samples are shown in Table 1.

As is clear from the margin 's1 table below, the products of the present invention are substantially rated as A, while the products other than those of the present invention include B, but most of them are rated CD. In terms of coatability and plate surface staining, in the present invention, the evaluation is substantially A to B, whereas in the case of those other than the invention, the evaluation is D. Regarding the leveling property, the present invention is rated A, whereas the non-inventive samples are rated CD.

Example 2 A photosensitive solution having the following composition was prepared, and the aluminum plate prepared in Example 1 was grained, and then coated on the aluminum plate using a roll coater, dried at 90°C for 4 minutes, and made into a negative type. A lithographic printing plate sample No. 10 was obtained. In addition,
The photosensitive coating amount was 16 mg/da2.

[Coating liquid composition of photosensitive liquid: molar ratio of charged monomers: N-(4-hydroxyphenyl) methacrylamide: acrylonitrileconityl acrylate: methacrylic acid: n-butyl acrylate = 8
:32:40:10:10 raw material
Copolymer obtained by the method shown in Synthesis Example 1 of Publication No. 045 (average molecular weight 55,000)
12. Hexafluorophosphate (average molecular weight 2400) of condensation resin of Ogp-diazodiphenylamine and paraformaldehyde (molar ratio 1:0.9)
0.48g Jurimer AC-1OL [manufactured by Hiki Junyaku Co., Ltd.] 0
．． 36g Victoria Pure Blue B OH0.12g Ethylene glycol monoacetate 30g Diethylene glycol dimethyl ether 70g Sample N except that the organic solvent composition in the photosensitive solution was replaced with the compound shown in Table 2 C.
Sample Nos. 11 to 19 of photosensitive liquid in the same manner as No. 10.
was created.

Samples 10 to 19 thus obtained were evaluated in exactly the same manner as in Example 1, and the results are shown in Table 2.

[Development conditions] Developer: Phenyl cellosolve 480g Jetanolamine (80%) 159g Bionin A4
413 (manufactured by Tokuhatsu Yushisha) 180g water
12
℃ automatic developing machine: Konica PS version automatic developing machine rPSK-910J (manufactured by Ynica Corporation) Development temperature = 2
7℃ Development time = 20 seconds [Printing conditions Printing machine: Heidel GTO Printing ink: Toyo King New Bright Red (manufactured by Toyo Ink Co., Ltd., oil-based ink) Printing paper: High quality paper Printing speed: 8000 sheets/hour [Diazo remaining] "Diazo residue" means that in a negative photosensitive lithographic printing plate using a diazo resin, the organic dye in the photosensitive resin or photosensitive composition is completely removed even in the non-image areas of the printing plate after development. However, it is a phenomenon that remains. This may cause staining of the printing plate in non-image areas, but it is also a problem because it deteriorates the plate inspection properties and becomes smudged after erasing the printing plate, causing trouble during printing.

[Method for evaluating diazo residue] An unexposed sample is developed using a developer under standard conditions under the development conditions shown in Examples. After that, part of the sample is covered with light-shielding paper and exposed to light. At this time, the reflection density of the exposed area and the unexposed area was measured using a densitometer (Konica Densitometer PDA-65, manufactured by Konica Corporation), and the difference between the two values is shown in the table. The smaller the value, the less the photosensitive composition remained before exposure, which is preferable.

Margin below! As is clear from Table J2, in the present invention, the coatability and staining of the plate surface are practically rated as A, although there is some B, whereas in the case of the products other than the present invention, although there is B, most of the stains are rated as A. It is CD. Regarding the diazo residue, the value of the present invention is small at 0.03 to 0.05, whereas the value is relatively large at 0.09 to 0.13 for the products other than the present invention.

The leveling property of the present invention is A, which is good.

[Effects of the Invention] The present invention uses ethylene glycol monoacetate and/or ethylene glycol diacetate as a solvent for the photosensitive coating solution, which improves odor, reduces toxicity, and improves the leveling and coating properties of the photosensitive coating solution. Also, a photosensitive coating liquid with improved plate surface staining can be obtained.

Furthermore, a photosensitive coating liquid with improved diazo residue can be obtained.

Claims (1)

[Claims] A photosensitive coating liquid characterized by containing ethylene glycol monoacetate and/or ethylene glycol diacetate as a coating solvent.