JPS59154443A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To improve film property and to form a picture image having durability for printing in a photosensitive compsn. to be used for a photosensitive lithographic plate which is developable with fresh water or aq. alkali soln by incorporating a resin having tert N atoms and being soluble or swellable in water as binder to the photosensitive resin compsn. CONSTITUTION:The titled compsn. contains a photosensitive diazo comps. and a resin having tert N atoms and being soluble or swellable in water. Suitable resins are amine modified epoxy resin obtained by reacting prim or sec amine with an epoxy resin or polymers or copolymers having recurring units expressed by the formula or copolymers with other monomer. In the formula, R1 is H or methyl; R2 is alkylene or hydroxy-substituted alkylene; R3 and R4 are alkyl, aryl, alkaryl or aralkyl, or substituted alkyl, aryl, alkaryl, aralkyl with alcoholic OH group or halogen.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photosensitive composition suitable for use in photosensitive lithographic printing plates, and more particularly to a novel photosensitive composition that can be developed with fresh water or aqueous Burqa IJi solution.

Typical negative photosensitive materials for printing materials are:
Diazonium compounds, quinonediazide compounds, azide compounds, photodimerizable resins, photopolymerizable resins, etc. are known, but diazonium compounds are generally used widely because of their excellent adhesion to substrates and developability. Among them, so-called diazo resins, represented by the formaldehyde condensate of p-diazodiphenylamine, are commonly used, and are used as sensitizers for photolithography in 28 plates and wipe-on plates.However, photocurable resins composed of diazo resin alone are There are problems in that the film forming properties are weak and sufficient printing durability cannot be obtained, and furthermore, the oil sensitivity is weak so that it is not possible to obtain a sufficient image C degree during printing. Various measures have been taken to improve this problem. has been completed and put into practical use.

The composition of the photosensitive layer of this type of photosensitive printing material can be classified into two types: those containing a diazo resin alone, which are referred to as external type, and those in which a diazo resin and a binder are mixed, which are referred to as internal type. After development, the external type requires application of emulsion lacquer to strengthen the image.
This lacquering process requires skill and has the drawback of being troublesome. On the other hand, in the case of an internal mold type in which a photosensitive layer having a desired abrasion resistance is provided in advance, a water-insoluble lipophilic resin as described in Japanese Patent Publication No. 47-1167 is usually used as a binder. This is because when a water-bathable resin such as polyvinyl alcohol is used as a binder, the image that should become the print area has little or no oil sensitivity.However, a hydrophobic resin is used as a binder. Because of this, it is no longer possible to develop with fresh water or an aqueous alkaline solution, and in order to process with normal development time, an organic bath agent such as benzyl alcohol as described in JP-A No. 55-44202 is required. It is essential to use a developer containing 4). However, the development of lithographic printing plates utilizes the difference in solubility or degree of swelling between exposed and non-exposed areas, and if an organic solvent is included in the developer, the image area will also swell during development. , some of the solvent permeates into the image area and remains.

As a result, if the residual solvent is not removed sufficiently and the printing press is exposed to U'', the printing durability will be significantly reduced, and the image will run relatively early in the printing process. This is often experienced by those skilled in the art when a PS plate coated with this type of photosensitive agent is run on a printing press immediately after development.

In view of the above circumstances, the present inventors investigated a photosensitive composition that does not require lacquering and can be developed with fresh water or an aqueous alkaline solution. It was discovered that the above drawbacks could be solved by using a resin as a binder (2).
, we have completed the present invention.

11] The present invention (a photosensitive diazo compound and a water-soluble or swollen OJ'-capable resin having a tertiary nitrogen atom (
2. This composition (1) can be easily developed with fresh water or aqueous alkaline 6 liquids, (2) has excellent film-forming properties and does not require lacquering. Forms images with sufficient printing durability, (3) Diazo compound resin has good phase M properties and provides a uniform and smooth photosensitive layer coating, (4) Has sufficient sensitivity and short exposure time. (5) The image formed by exposure has excellent oil sensitivity; (6) Either water or an organic solvent can be used as a diluent when preparing a coating solution, etc. It has the characteristics of

The photosensitive diazo compounds that can be used in the present invention are diazo-aromatic compounds, more particularly diazo-arylamines which can be substituted on the aromatic nucleus or on the amino-nitrogen;
Preference is given to p-diazo-diphenylamine and its derivatives, such as its condensation products using organic condensing agents containing reactive carbonyl groups such as aldehydes and acetals, especially formaldehyde, zinc chloride and paraformaldehyde. These are compounds and condensates.

Seven reaction products of the above diazo compound and a suitable coupling agent can be used in the present invention; It is an organic compound that does not significantly reduce its photosensitivity and produces a reaction product that is soluble in organic solvents, but only slightly soluble in water. Such coupling agents generally include acidic aromatic compounds such as phosphinic, phosphonic, sulfonic and carboxylic acids of benzene, toluene and naphthalene and their derivatives such as their alkali metal salts; hydroxyl-containing aromatic compounds; Phenolic compounds such as alizarin, including diphenolic acids, benzophenones, substituted benzophenones, naphthols, naphthalene diols, and sulfonic acids and their alkali metal sulfonates; and stearic acid and ethylenediaminetetraacetic acid. It is an acidic aliphatic compound. Additionally, inorganic salts such as hexafluorophosphate and tetrafluoroboric acid can also be used as coupling agents.

Resins that can be used in the present invention include the following.

[■] Amine-modified epoxy resin obtained by the reaction of an epoxy resin and a primary or secondary amine A suitable epoxy resin is a reaction of a polyhydric phenol such as bisphenol A1 bisphenol/l/F or hisphenol S with epichlorohydrin. A bisphenol type epoxy resin obtained by the reaction of a novolak resin of a monohydric phenol such as carbolic acid or p-tert-butylphenol with epichlorohydrin. Usable primary or secondary amines include, for example, dimethylaminopropylamine, diethylaminopropylamine, digtylaminopropylamine,
N-aminoethylmorpholine, N-aminopropyl-2
-pipecoline, N-7minoethylbiverazine, N-methylbiperazine, N-N-N'-)dimethylethylenediamine, N-N-dimethylethylenediamine; diethylamine, di-n-propylamine, diimpropylamine, di-n- Butylamine, diisobutylamine, dicyclohexylamine, dibenzylamine, piperidine, α
~Rubibecolin N-methylaniline, N-ethylani+
)7. N-methylcyclohexylamine, N-pencylaniline, N-#-rubenzylamine, morpholine, pyrrolidine, ceverazine, N-(tert-butyl)-N
-Hydroxyethylamine, N-phenyl-N-ethanolamine, jetanolamine, diisopropanolamine, monomethylamine, monoethylamine poly, 7-n-propylamine, monoisopropylamine, mono-
n-butylamine, monoisobutylamine, mono-5e
c-butylamine, mono-tert-butylamine, mono-2-ethylhexylamine, monocyclohexylamine, monobenzylamine, aniline, toluidine, 6
-Medoxyglobylamine, 3-aminopropionitrile, p-nido-roaniline, 0-77minoacetonoenone, p-bromoaniline, dimethylamine, diphenylamine, ethylenediamine, m-phenylenediamine,
1,2-diaminocyclohexane, benzidine, 4,4
Nidiaminodiphenylmethane, diethylene monoamine, monoethanolamine, monoisoglobanolamine, l-lishydroxymethyl aminomethane or 2-
Compounds such as amino-2-methylpropanol-1 can be mentioned, and these can be used alone or in combination of two or more.

Vinyl polymers having repeating units of vinyl monomers having tertiary amino groups Usable polymers include the general formula (wherein R1 represents a hydrogen atom or a methyl group, and R2 represents an alkylene group or a hydroxyl group). represents a substituted alkylene group, and R3 and R4 are an alkyl group, an aryl group,
It represents an alkaryl group or an aralkyl group, or a group thereof substituted with an alcoholic hydroxyl group or a halogen atom, and R3 and R4 are bonded together to form a heterocyclic group (may be . . . ) There are polymers or copolymers having repeating units represented by the above formula, or copolymers with other vinyl monomers (hereinafter, these are referred to as backbone polymers).

Here, these backbone polymers have a tertiary amino group represented by the general formula % (21 (However, R1 to R4 follow the definitions in the above general formula (1)). Vinyl monomers having ester bonds [hereinafter referred to as monomers (A
). ] alone or in mixtures thereof, or other vinyl monomers copolymerizable with these [hereinafter, these will be referred to as monomers (B). ] using a polymerization initiator.

(2) A (co)polymer obtained by (co)polymerizing the monomers acrylic acid chloride and/or methacrylic acid chloride, or the monomer and the above monomer (B
A method in which a copolymer obtained by polymerizing a mixture with 1 and 1 using a polymerization initiator is subjected to an esterification reaction with a 6th-class alkanolamine compound.

(3) Ester moieties such as glycidyl methacrylate, glycidyl acrylate, 2-methyl-2,6-eboxyglobyl methacrylate and 2-methyl-2,6-nipoxyprobyl acrylate, etc. A (co)polymer obtained by (co)polymerizing at least one monomer selected from the group of acrylates and methacrylates having an epoxy group or a mixture of the monomer and the monomer]B) using a polymerization initiator. It can be obtained by a method in which a combination is subjected to an addition reaction with a mono-secondary amine compound.

As the monomer (A), any vinyl monomer having a 6th amino group and an ester bond represented by the general formula (2) can be used; is ■methacrylic acid, acrylic acid, methacrylic acid chloride, or an equimolar ester of acrylic acid chloride and a 6th class alkanolamine compound, or ■glycidyl methacrylate 1, glycidyl acrylate, 2-methyl-2・Equimolar adducts of acrylates or methacrylates having an epoxy group, such as 6-epoxypropyl methacrylate or 2-methyl-2,6-eboxyglopylacrylate, and mono-secondary amino group compounds, etc. I can make a fist.

Here, the above-mentioned 6th-class alkanolamine compound refers to a compound having a 6th-class amino group and an alcoholic hydroxyl group, such as triethanolamine, triinglobanoylamine, 2-dimethylaminoethanol, 2-dimethylaminoethanol, etc. Diethylaminoethanol, 2-diinoprobylaminoethanol, 2-di-n-butylaminoethanol, 6-dimethylamitubrobanol, 1-dimethylaminozolopanol-2, N-methyl-N-N-jetanol Amine, N-3=-methoxyprobyl-N-N-
Jetanolamine, N-2-hydroxyethylpiperidine, N-2-hydroxyethylpipecoline or N
-Human old palm ether morpholine, etc. may be mentioned.

Furthermore, a mono-6th class amine compound is a compound having one secondary amino group, such as dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, dibenzylamine, diphenylamine, piperidine, Examples include pipecoline, morpholine, N-methylaniline, N-methylcyclohexylamine, N-ethylaniline, N-benzylaniline, and N-methylbenzylamine.

Furthermore, as the monomer (B), the monomer (
A), acrylic acid chloride, methacrylic acid chloride, or monomers that can be copolymerized with acrylic acid chloride or methacrylate having an epoxy group are not particularly limited; J
- Rubenzene device (methyl, ethyl, pY as a ring group)
Viru, isozorobyl, n-butyl, isobutyl, sec-butyl, 6-butyl, amyl, 2-ethylhexyl, octyl, capryl, nonyl, dodecyl, hexadecyl,
12a-containing acrylates such as octadecyl, cyclohexyl, metquinethyl, butoxyethyl, 2-hydroxyethyl, 2-hydroxypropyl, 6-diIJIJ-2-hydroxypropyl, allyl, methacryl, oleyl or te)-rahydrofurfuryl, Methacrylate or fumarate: monoacrylate or monomethacrylate of polyethylene glycol or monoacrylate V-) or monomethacrylate of polypropylene glycol; 2-13 to 4-vinylpyridine vinyl acetate, vinyl butyrate or vinyl benzoate; acrylic acid or methacrylic acid Niacrylamide, methacrylamide, N-hydroxymethylacrylamide or N-hydroxymethylmethacrylamide, acrylonitrile, maleic anhydride, etc., are used alone or in a mixture of 2'4M or more.

[■] Polyurethane resin obtained by the reaction of a polyhydric alcohol containing a 6th bubblycanolamine with polyisocyanate 1. Examples of 6th alkanolamines that can be used include 2-diethylaminoethanol, 2-diimpropylaminoethanol, 2-n-bunalaminoethanol, 6
-dimethylamitubulovanol, 1-dimethylamitubrobanol-2, N-2-hydroxyethylpiperidine, N-2-hydroxyethylpipecoline, N-hydroxyethylmorpoline, N,N-dihydroxyethylpiperazine, NlN Compounds such as -dihydroxyethylaniline, N-methyl-N, N-jetanolamine, N-3-methoxygloby-N, N-diethanolamine, triethanolamine, and triisopropanolamine can be mentioned; They may be used alone or in combination of two or more.

The component of the polyhydric alcohol may be composed of one or more of the above-mentioned tertiary amino alfurs (or may be composed of a combination of other polyhydric alcohols. Examples of polyhydric alcohols include ethylene glycol, fluoropylene glycol, diethylene glycol, dipropylene glycol, 1-6-
Examples include butylene glycol, 1,4-butylene glycol, neopentyl glycol, trimethylolpropane monoacetate, glycerin, trimethylolpropane, trimethylolethane, etc., and these may be used alone. The above may be used in combination.

Examples of the polyincyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, 6,6'-dimethyldiphenylmethane-4,4'-cyisocyanate)-,2,
4-) IJ diisocyanate dimer, 1,5-naphthylene diisocyanate, hexanetriol and 2.
Triphenylurethane reaction product with 4-tolylene diisocyanate, triphenylurethane reaction product with trimethylolpropane and 2,4-tolylene diisocyanate, metaphenylene diisocyanate, triphenylmethane-4,4'. Examples include 4''-triisocyanate, hexamethylene diisocyanate, and the like, and these polyincyanate compounds may be used alone or in combination of two or more.

Among the above-mentioned resins used in the present invention, preferred are
The content concentration of class nitrogen atoms is 1% by weight based on the total weight of fat-resistant
It is 01-20%. If the concentration is less than 0.01%, the developability with fresh water or alkaline water decreases, and 20%
This is because the oil sensitivity is lowered by the above.

The photosensitive composition of the present invention is prepared by dissolving the above-mentioned diazo compound and resin in a suitable solvent, and the solvent may be a certain type of organic solvent or a mixed solvent of this and water. For organic bath solvents such as methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, acetone, methyl ethyl ketone, propatool, dimethinenoformamide, and dimethyl sulfogide, a mixed solvent of these and water is suitable. The composition of the present invention may contain a certain kind of acid or salt, which prevents the dark reaction and decomposition of the diazo compound and dramatically improves the bath stability and storage stability of the composition. be able to. Such acids and salts include, for example, organic carboxylic acids such as formic acid, acetic acid, propionic acid, crotonic acid,/tronic acid, malonic acid, tartaric acid, lactic acid; benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfonic acid, 2. 5-dimethylbenzenesulfonic acid,
Organic sulfonic acids such as sodium benzenesulfonate, lauryl ether sulfate, argylaryl sarnoate, p-nonylphenol sulfate, or their ammonium or alkali metal salts; inorganic acids such as phosphoric acid can be used, and their preferred addition The amount is 10 to 200 equivalent % based on tertiary nitrogen atoms. The amount is 10
If the amount is less than 200%, the effect will not be significant, and if it exceeds 200%, the impressionability will decrease.

The blending ratio of the diazo compound and resin included in the composition is 5:2
~2:5 (weight ratio) is suitable.

A printing plate having a uniform and stable photosensitive layer can be produced by coating and drying the M parabolite prepared in the step box on a support. A suitable coating amount in this case is 02 to 29 parts m2 in terms of solid content %. As the support, dimensionally stable plates conventionally used for printing plates can be used, such as metal plates of aluminum, zinc, copper, iron, etc.; cellulose acetate, cellulose propionate, - Composite plastic sheets, etc., in which the above metals are laminated, vapor-deposited or fixed to plastic films such as cellulose, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, and polyvinyl acetal, can be used.

After exposure, the photosensitive layer formed using the composition of the present invention is exposed to fresh water. < can be developed using an aqueous alkaline solution.

Examples of alkaline agents for aqueous alkaline developers include anhydrous sodium sulfite, sodium lauryl sulfate, lithium benzoate, and sl-! benzoate. J = fym, sodium silicate, potassium hydroxide, tertiary sodium phosphate, dibasic sodium phosphate, tertiary potassium phosphate, dibasic potassium phosphate, dibasic ammonium phosphate, dibasic ammonium phosphate,
Examples include sodium metasilicate, sodium bicarbonate, sodium carbonate, potassium carbonate, and the like. In this case, the preferred content of the alkaline agent in the developer is 0.05 to 5N%.

Even when the printing plate made using the photosensitive composition of the present invention is printed on a printing press immediately after development, there is no phenomenon such as image bleeding, and a good printed matter with excellent oil sensitivity can be obtained.

Next, the present invention will be specifically explained with reference to Examples.

Parts and percentages in the examples are by weight.

Example 1 Preparation of resin] Ebicuron 1050J (bisphenol A type epoxy resin manufactured by Inu Nippon Ink Chemical Industry ■: epoxy equivalent 47Q)
244 parts of jetanolamine and 125 parts of Improvil alcohol were reacted under reflux at 80° C. for 6 hours to obtain a liquid amino-modified epoxy resin. (Hereinafter, this will be referred to as resin A.) (The content of tertiary nitrogen atoms is 2.6
%) 11 parts of propionic acid and 2 parts of water per 50 parts of resin A
50 parts were added to obtain a colorless and transparent homogeneous aqueous solution (hereinafter referred to as resin B). Preparation of photosensitizer solution Condensation product of p-diazodiphenylamine and paraformaldehyde (hereinafter referred to as diazo condensation product) 2-hydroxy-4-methoxy-benzophenone-5-
A uniform photosensitive composition solution was prepared by mixing 2.5 parts of the sulfonic acid salt and 6.5 parts of the resin A with 85 parts of methyl cellosolve and 9 parts of dimethylformamide.

For the preparation and printing of printing plates, prepare a printing plate support on the surface of synthetic paper with epoxy resin and dimer polyamide resin as a binder and fine zinc particles fixed thereon, and add 5 parts of diammonium phosphate, 5 parts of ammonium nitrate, The surface of the support was desensitized by immersion for 1 to 2 minutes in a treatment solution consisting of 6 parts of succinic acid, 2 parts of phosphoric acid, 6 parts of glycerin, and 82 parts of water.

The photosensitive composition solution was uniformly applied to the printing original plate obtained in this way using a wheeler, and dried at 100° C. for 1 minute. The coating film after drying was uniform and smooth, and the coating weight was 1.
The photosensitive printing plate (obtained by
PS plate) was exposed for about 2 minutes through a negative film and then developed in a water bath containing 1.5% sodium benzoate and 6.0% sodium lauryl sulfate. The development operation was completed by simply immersing and shaking in the above solution for 1 minute, and no mechanical rubbing of the plate surface was required. After washing with water, the plate was immediately transferred to a small offset printing machine (Model 626 manufactured by A B DICK). When the printer was attached to the printer and printed, io, ooo copies of good reproduction prints were obtained.

Example 2 Preparation of resin While refluxing a solution of 60 parts of isopropyl alcohol and 2 parts of azobisisobutyronitrile, 40 parts of glycidyl methacrylate, 20 parts of droxyethyl methacrylate, 40 parts of butyl acrylate and azo A mixture consisting of 2 parts of bisisobutyronitrile was added dropwise over a period of 2 hours, and even after the addition was completed, the reaction was continued under reflux for another 6 hours to obtain a copolymer. Next, 15 parts of diimpropyl alcohol and 30 parts of inpropyl alcohol were added to this, and the mixture was reacted at reflux temperature for 6 hours to obtain a liquid amine-modified acrylic resin. (Hereinafter, this will be referred to as resin C.) (Content of 6th class nitrogen atoms is 1.4%) 10% phosphoric acid aqueous solution 25% at room temperature for 9D parts of resin C
10 parts of ethyl cellosolve and 670 parts of water were added to obtain a colorless and transparent homogeneous aqueous solution. (Hereinafter, this will be referred to as resin (・
5゜) 3.5 parts of tetrafluoroborate of the diazo condensation product and 6.5 parts of the resin C are dissolved in 85 parts of methyl cellosolve and 8 parts of dimethylformamide to prepare a uniform photosensitive composition solution (~ is.

Preparation and printing of the printing plate This solution was coated on the printing plate support in the same manner as in Example 1,
After exposure through negative film, development was performed.

A water bath solution containing 1.5% diammonium phosphate and 10% dibasic sodium phosphate was used as the developer, and good image areas and non-image areas were quickly formed with only immersion shaking and 5 operations. 10,000 good copies of printed matter were obtained by applying ink and printing.

Example 6 Preparation of resin Novolac type epoxy resin 1169 (Ciba Geigy)
A liquid amine-modified epoxy resin was obtained by reacting 158 parts of epoxy equivalent (175), 96 parts of di-n-butylamine, and 85 parts of isopropyl alcohol under reflux at 80°C for 3 hours. (Hereinafter, this will be referred to as Resin E.) (The content of 6th class nitrogen atoms is 6.2%) 6.5 parts of tetrafluoroborate of the diazo condensation product and 2.8 parts of Resin E are mixed with 94 parts of methyl cellosolve. A homogeneous photosensitive composition G solution was prepared by dissolving the photosensitive composition.

After the grained aluminum plate is treated with hexafluorozirconic acid to make it desensitized, the photosensitive composition solution is applied,
Exposure was done through negative film. Development was completed by simply immersing and shaking for 1 minute in a water bath containing 1% sodium benzoate and 2% sodium lauryl sulfate, and good quality image areas and non-image areas were formed. When this plate was attached to an offset printing machine (Faboritsu RFDI manufactured by Roland Co., Ltd.) and printed, io and coo copies of good reproduced prints were obtained.

Example 4 Preparation of resin N,? 108 parts of f-bishydroxyisoglobil-2-methylbiperazine was heated to 50°C, and 1,6-hexamethylene diisocyanate was added thereto with sufficient stirring.
68 parts were gradually added dropwise over 5 hours. 60 minutes after completion of dripping
The reaction was carried out at ℃ for 4 hours to obtain an incyanate-terminated prepolymer. The content of isocyanate groups in this prepolymer was 73%. Next, 26 parts of phenol, 20 parts of methyl ethyl ketoxime, and 20 parts of dimethyl formamide were added and reacted at the same temperature for 5 hours to obtain a liquid modified polyurethane resin.

(Hereinafter, this will be referred to as resin F.) (The content of 6th class nitrogen is 8.8%) This modified polyurethane resin is diluted with 95 parts of isopropyl alcohol and neutralized with a 65% acetic acid water bath. It can be a clear solution soluble in

3 parts of 2-hydroxy-4-methoxy-7-penzophenone-5-sulfonate of the diazo condensation product and 2.5 parts of resin F were mixed with 85 parts of methyl cellosolve and 9 parts of dimethylformamide.
A homogeneous solution of the photosensitive composition was prepared by dissolving the photosensitive composition in 1 part.

Preparation of printing plate Apply this solution on the printing plate support in the same manner as in Example 1,
After exposure through negative film, development was performed.

The developing solution was completed by simply dipping and shaking for 1 minute in an aqueous solution containing 1.5% sodium benzoate and 1.5% sodium lauryl sulfate, and good quality image areas and non-image areas were formed.

Example 5 A uniform aqueous solution of a photosensitive composition was prepared by dissolving 6 parts of the sulfate of the diazo condensation product and parts of the resin B2O in 67 parts of water.

Apply this water bath solution onto a grained aluminum plate.
, exposure and development operations were performed. Use fresh water for development (・,
Unexposed areas can be washed off with tap water. The printing plate thus obtained had high-quality printed areas and non-printed areas, and after being rubberized, it was immediately mounted on a small offset printing machine and printed, resulting in 5,000 good reproductions. Obtained.

Example 6 A uniform bath solution of a photosensitive composition was prepared by dissolving 6 parts of the tetrafluoroborate salt of the diazo condensation product and 20 parts of the resin D in 66 parts of water and 7 parts of dimethylformamide. Using this solution, a printing plate was prepared in the same manner as in Example 5 (-1 printing was performed, and 5.0 (: 10 good copies were obtained).

Example 7 2-Hydroxy- of the diazo condensation product in Example 1
4-Methoxy-benzophenone-5-sulfonate2.
5 K[,'M fat A 3.5 parts, methyl cellosolve 85
A uniform photosensitive composition was prepared by adding 09 parts of p-toluenesulfonic acid (equivalent to 1 to 100 equivalent % based on the 6th class nitrogen atom) to a solution of a photosensitive composition consisting of 1 part and 9 parts of dimethylformamide. A bath solution was prepared. This bath solution exhibited storage stability for 20 days or more without producing any pebble-like substances as a by-product. The PS plate prepared in the same manner as in Example 1 could be easily developed with an aqueous alkaline solution and formed good quality image areas and non-image areas. In addition, the storage stability of the photosensitive layer of the PS plate is also good, and 5
Even after being stored for 20 days at 0°C and 60% RH, it showed the same developability and oil sensitivity as the initial stage.

Example 8 2-hydroxy was added to a bath solution of a photosensitive composition consisting of 6.5 parts of tetrafluoroborate of a diazo condensation product, 2 parts of cationic water-soluble resin A, 85 parts of methyl cellosolve, and 9 parts of dimethylformamide. -4-Methoxy-benzophenone-
04 parts of 5-sulfonate and 0.1 part of propionic acid (corresponding to 90 equivalent % with respect to the 6th class nitrogen atom) were added to prepare a uniform solution of the photosensitive composition. This solution is 20
It exhibits storage stability for more than 1 day, and has good storage stability when made into a PS plate.
Even after storage for several days, the developability and oil sensitivity remained the same as at the initial stage. Development was completed by simply immersing and shaking for 1 minute in an aqueous solution containing 1% sodium benzoate and 1% sodium lauryl sulfate, and good quality image and non-image areas were formed. After washing with water, I immediately installed it on a small offset printing machine and printed.
Good reproduction prints with high image density were obtained from the beginning with almost no waste paper.

Agent: Patent attorney Katsutoshi Takahashi

Claims (1)

[Scope of Claims] t A photosensitive composition comprising (a) a photosensitive diazo compound and (b) a water-soluble or swellable resin having a 6th class nitrogen atom. The composition according to claim 1, wherein the resin (b) is an amine-modified epoxy resin obtained by reacting an epoxy resin with a primary or secondary amine. 3. (b) The resin has a general formula (wherein R1 is a hydrogen atom, represents a methyl group, R2 represents an alkylene group or an alkylene group substituted with a hydroxyl group, and R3 and R4 are an alkyl group or an aryl group. ,
It represents an alkaryl group or an aralkyl group, or a group thereof substituted with an alcoholic hydroxyl group or a halogen atom, and R3 and R4 may be bonded together to form a 1-heterocyclic group. ) The composition according to claim 1, which is a polymer or copolymer having a repeating unit represented by the following formula or a copolymer with other vinyl monomers. 4. The composition according to claim 1, wherein the resin (4) is a polyurethane resin obtained by reacting a polyhydric alcohol containing a 6th-class alkanolamine with a polyinsyanate. 5(b) Claims 1 to 4, wherein the content of tertiary nitrogen atoms in the resin is 01 to 20% of the total weight of the resin.
Parabola of terms. & Claims 1 to 5 containing organic carboxylic acid, organic sulfonic acid, phosphoric acid, or salts thereof as necessary.
composition of the term. l The content of organic carboxylic acid, organic sulfonic acid, phosphoric acid, or their salts is (b) 10 to 10% of the tertiary nitrogen atoms in the resin.
7. The composition of claim 6, wherein the composition is 200 equivalent %.