JPH036561A - Developing solution for damping waterless planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain excellent developability and dot reproducibility by incorporating one or >=2 kinds of specific compds. into the developing soln. CONSTITUTION:One or >=2 kinds of the compds. expressed by formula I are incorporated into the developing soln. In the formula I, Y denotes hydrogen, alkyl group or phenyl group. The more specific examples of the compds. expressed by the formula I include 1, 3-dioxorane-2-on, 4-methyl-1, 3-dioxoran-2- on, 4-phenyl-1, 3-dioxorane-2-on, 4-benzyl-1, 3-dioxorane-2-on, 4-ethyl-1, 3- dioxorane-2-on, and 4-hexyl-1, 3-dioxorane-2-on, etc. Particularly the 4-methyl 1, 3-dioxoran-2-on among the above-mentioned compds. is more preferably used. The developing soln. which has the excellent developability suitable for the development of the damping waterless planographic printing plate material and has the good dot reproducibility is obtd. in this way.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a developer for lithographic printing plate materials that does not require dampening water, and more specifically, a developer that can be used to develop lithographic printing plate materials that do not require dampening water. The present invention relates to a developer that can improve the developability of the lithographic printing plate material and also improve the halftone reproducibility, that is, the reproducibility of shadow areas and the reproducibility of small dots, of the lithographic printing plate formed by the development.

[Background of the invention]

Conventionally, a lithographic printing plate material (hereinafter also simply referred to as "plate material") that does not require warm water, which is formed by coating a support with a photosensitive layer and an ink-repellent layer in order from the support side, is exposed to light. In order to obtain a lithographic printing plate (hereinafter simply referred to as a "printing plate") that does not require dampening water by development, for example, aliphatic hydrocarbons (hexane, heptane, "Isopar E,"
H, G” (manufactured by Esso Chemical Co., Ltd., a trade name for aliphatic hydrocarbons) or gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, meta-xylene hexafluoride, etc.)
, or halogenated hydrocarbons (trichlorethylene,
(perfluorohexane, etc.) and the following polar solvents, namely alcohols (methanol, ethanol, etc.), water, ethers (methyl cellosolve, ethyl cellosolve,
butyl cellosolve, methyl carpitol, ethyl carbitol, butyl carpitol, dioxane, etc.), ketones (acetone, methyl ethyl ketone, etc.), esters (
Ethyl acetate, methyl cellosolve acetate, cellosolve acetate, carpitol acetate, etc.) are used to create a plate material, for example, a plate material in which a photosensitive layer and a silicone rubber layer are provided on a support in this order from the support side. As a developer for developing, JP-A-57-134
No. 48 discloses a developer containing a propylene oxide derivative, JP-A No. 61-275759 discloses a developer containing an organic solvent, a surfactant, and water, and JP-A No. 59-Sho 59-275759 discloses a developer containing an organic solvent, a surfactant, and water.
Publication No. 146054 discloses a developer containing 0.05 to 5% water and a hydrocarbon.

However, developing plate materials with conventional developers containing the above-mentioned solvents generally takes time, and the resulting printing plates do not have sufficient dot reproducibility. In an attempt to shorten this time, if a developer containing a solvent that has high solubility in the photosensitive layer is used, the reproducibility of the shadow areas of the printing plate will be poor. It is necessary to use a large amount of solvent to swell the plate material, and if the plate material is rubbed too hard in an attempt to shorten the development time, the silicone rubber layer will be damaged, and conventional developers generally do not provide sufficient developability. Not yet.

In particular, the developer disclosed in JP-A-57-13448 and the like is applicable to a developing method that removes only the silicone rubber layer by utilizing photoadhesion between the photosensitive layer and the silicone rubber layer caused by exposure. However, for a development method in which both the silicone rubber layer and the photosensitive layer are removed by development, the adhesive strength between the exposed photosensitive layer and the support, the brimer layer or the silicone rubber layer, especially the silicone rubber layer, is suitable. Because it weakens it more than necessary, it was not possible to obtain satisfactory results.

Furthermore, although the developer disclosed in JP-A No. 61-275759 has improved safety by containing 30% by weight of water, it does not give satisfactory results in terms of developability, especially development speed. is not obtained.

Therefore, as a result of various studies in view of the above-mentioned situation, the present inventors have developed a developer solution containing one or more of the compounds represented by the following general formula (■), which eliminates the need for dampening water. When developing a lithographic printing plate material, excellent developability is exhibited, and a printing plate with improved halftone dot reproducibility is produced in a relatively short time, and
Even if the developer contains 30311% or more water,
In addition, with the purpose of providing a developer that exhibits excellent developability and halftone dot reproducibility, the following general formula! A developer for lithographic printing plate materials that does not require dampening water and is characterized by containing one or more of the compounds represented by: [wherein Y represents hydrogen, an alkyl group, or a phenyl group]. ] was found.

[Object and structure of the invention]

The present invention was invented based on the above-mentioned findings, and is used for developing lithographic printing plate materials that do not require dampening water [wherein Y represents hydrogen, an alkyl group, or a phenyl group]. ].

[Detailed description of the invention]

The present invention will be explained in more detail below.

Specific examples of the compound represented by the general formula 1 (hereinafter also referred to as the compound of the present invention) include 1. 3=dioxolan-2-one, 4-methyl-1,3-dioxolan-2
-one, 4-phenyl-1°3-dioxolan-2-one, 4-benzyl-1°3-dioxolan-2-one,
4-ethyl-1°3-dioxolan-2-one and 4
-hexyl-1,3-dioxolan-2-one, etc., among which 4. -Methyl-1,3-dioxolan-2-one is preferably used.

The developer of the present invention generally contains 1 to 100% by weight, preferably 2 to 80% by weight, more preferably 5 to 1% by weight of one or more compounds represented by the general formula (1), and the remainder contains ingredients used in conventional developers, such as optionally alcohols such as methanol, ethanol, l-butoxy-2-propanol, 3-methyl-3-methoxybutanol and benzyl alcohol, methyl cellosolve, Ethyl cellosolve, butyl cellosolve, phenyl cellosolve, methyl carpitol, ethyl carpitol, butyl carpitol, dioxane,
Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, ethylene glycol dibutyl ether,
Ethers such as propylene glycol ether, dipropylene glycol butyl ether, tripropylene glycol methyl ether and polypropylene glycol methyl ether, acetone, methyl ethyl ketone,
Ketones such as methyl isobutyl ketone and diisobutyl ketone, ethyl acetate, propyl acetate, hexyl acetate, methyl butyrate, propyl butyrate, diethyl succinate, dibutyl oxalate, diethyl maleate, benzyl benzoate,
Esters such as cellosolve acetate, methyl cellosolve acetate and carpitol acetate and polar solvents such as water, and hexane, heptane, °“
Isopar E・H,G” (manufactured by Esso Chemical Co., Ltd., trade name of aliphatic hydrocarbons), aliphatic hydrocarbons such as gasoline and kerosene, aromatic hydrocarbons such as toluene and xylene, and trichlorethylene The solvent may contain one or more nonpolar solvents such as halogenated hydrocarbons such as halogenated hydrocarbons.

The developer of the present invention can contain a surfactant, and examples of the surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene Nonionic surfactants such as sorbitan fatty acid ester, glycerin fatty acid ester, oxyethylene oxypropylene block polymer, fatty acid salt, alkyl sulfate ester salt, alkylbenzene sulfonate, alkylnaphthalene sulfonate, dialkyl sulfosuccinate ester, alkyl phosphate ester salt , naphthalene sulfonic acid-formalin condensate, anionic surfactants such as polyoxyethylene alkyl sulfate salts, cationic surfactants such as alkylamine salts, quaternary ammonium salts, polyoxyethylene alkylamines, and amphoteric surfactants such as alkyl betaines. Among them, anionic surfactants are suitable.

These surfactants can be used alone or in combination of two or more, and when a surfactant is used in the present invention, it is generally added in a concentration of 0.5 to 6
It is appropriate to contain 0% by weight, preferably 1 to 50% by weight.

The developer solution of the present invention may contain, in addition to the above-mentioned components and the compounds of the present invention, a significant amount of water, for example 30% or more by weight, and the preferred water content is determined by the amount of water used in addition to water. Although it varies depending on the compound of the invention, other components, usage conditions, type of printing plate material, etc., it is generally 50 to 95% by weight.

Here, specific examples of the developer of the present invention are as follows.

(1) Isopar H 1-99% by weight 4-methyl-1,3-dioxolan-2-one 1-99% by weight (2) Isopar H 5-85% by weight 4-methyl-1,3-dioxolan-2-one 5-85% by weight tripropylene glycol monomethyl ether 5-85% by weight (3) 3-
Methyl-3-methoxybutanol 2-80% by weight Isopar M 1-50% by weight 4-methyl-1,3-
Dioxolan-2-one 2-60% water by weight
30-95% by weight (4) Surfactant 1-30% by weight diethylene glycol dimethyl ether 1-80% by weight 4-methyl-1,3-dioxolan-2-one 2-50% by weight water
30-95% by weight (5) Isopar H 5-85% by weight 4-Methyl-1,3-dioxolan-2-one 5-85% by weight Tripropylene glycol monomethyl ether 5-85% by weight Diethyl succinate 1-10% by weight % The developer of the present invention can generally be used for any conventional lithographic printing plate material that does not require dampening water, but it is preferably applied to a support as a photosensitive layer and an ink repellent layer in this order from the support side. Examples of the fluororesin constituting the ink repellent layer of such a plate material include JP-A-52-74404, JP-A-52-74405, No. 58-83011, No. 58-
No. 88750, No. 58-90524, etc., which are conventionally known, or patent applications filed in 1988-90524.
No. 182466, No. 63-237680, and No. 6
It is possible to use any of the fluororesins that the present applicant had already proposed in applications such as No. 3-288129 by the time of filing this application.

Preferably, Japanese Patent Application Nos. 63-182466 and 63-2
The fluororesins described in the specifications of No. 37680 and No. 63-288129 are used, and for example, the following can be used.

(1) Has the following structural units in the molecule, CF, --CF, --CF-1CF, -0--CF, --
0- -CF-0- (Fluorine content is 30% by weight or more, preferably 50% by weight or more) and the compound in the molecule, directly or through a crosslinking agent, between fluororesins and/or in the photosensitive layer A fluororesin containing functional groups that can react with each other to form bonds.

Examples of the above-mentioned functional groups include the following functional groups.

OH, COOH, NHs, NH- The above fluororesin can be obtained by copolymerization of a fluorine-containing monomer and a monomer having the above functional group.

Specifically, the fluororesins exemplified below are preferably used.

■ Copolymer resin of perfluoroalkyl (meth)acrylate and allyl methacrylate ■ Copolymer resin of perfluoroalkyl (meth)acrylate and (meth)acrylic acid ■ Perfluoropolyether (meth)acrylate and (meth)acrylic acid Glycidyl (
Resin with added meth)acrylate■ Perfluoroalkyl(meth)acrylate and 2-hydroxyethyl(
Copolymer resin of meth)acrylate, alkyl(meth)acrylate, and acrylonitrile■ Perfluoroalkyl(meth)acrylate and 2-
The bond between the resin fluororesin layer and the photosensitive layer is formed by adding 2-methacroyloxyethyl isocyanate to the product obtained by copolymerizing hydroxyethyl (meth)acrylate, alkyl (meth)acrylate, and acrylonitrile. Fluororesin and
After dissolving the optionally added crosslinking agent in a suitable solvent,
By applying the solution onto the photosensitive layer, drying it, and then subjecting it to heat treatment, the fluororesin and the compound in the photosensitive layer are crosslinked via a crosslinking agent or directly.

The fluororesin layer is preferably crosslinked, and the crosslinking agent used with the fluororesin is a compound having two or more functional groups in its molecule that can react with the functional groups described in item (1) above. , preferably a polyisocyanate compound,
For example, hexamethylene diisocyanate, toluylene-2,4-diisocyanate, etc. are used in combination with a fluororesin having a hydroxyl group.

Next, silicone rubber, which is another material constituting the ink repellent layer in the plate material, will be explained.

The above-mentioned silicone rubber is a linear organic polyester having a repeating unit represented by the following general formula (2), a molecular weight of several thousand to several hundred thousand, and a hydroxyl group bonded in the main chain or at the end of the main chain. Those containing siloxane as a main component are preferably used.

General formula■ →5i-0±r where n is an integer of 2 or more, R is an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, an alkoxyl group, a vinyl group, an aryl group, or a silanol group (OH group). Preferably, 60% or more of R is a methyl group. The silanol group (OH group) may be located either in the main chain or at the end of the main chain, but is preferably located at the end.

Silicone rubbers useful in plate materials are obtained by condensation reactions of such silicone base polymers with silicone crosslinking agents such as those listed below.

(1) R-3i-←OR')s (2) R-3i-←0Ac)s (3) R-3t-←0N-CR' Ri! Here R is -
r has the same meaning as R, which is a substituent of the polymer represented by formula (■), and R' is an alkyl group such as a methyl group or an ethyl group,
Ac is an acetyl group.

These silicone rubbers are also available as commercial products, such as YE-3085 manufactured by Toshiba Silicone Corporation.

Other useful silicone rubbers are produced by the reaction of the above-mentioned base polymer with a silicone oil having the following general repeating units, or silicone rubbers in which about 3% of R is vinyl groups. It can also be obtained by an addition reaction with a base polymer or a reaction between the above silicone oils.

One ship type ■ (In the formula, R has the same meaning as R, which is a substituent of the polymer shown in the above general formula ■, m is an integer of 2 or more, and n is an integer of 0 or 1 or more.) Like this In order to obtain silicone rubber by a crosslinking reaction, the crosslinking reaction must be carried out in the presence of a catalyst. As this catalyst, organic carboxylates of metals such as tin, zinc, cobalt, lead, calcium, manganese, etc., such as diptyltin laurate, tin(II) octoate, cobalt naphthenate, etc., or chloroauric acid, etc. are used. .

In addition, in order to improve the strength of silicone rubber and obtain silicone rubber that can withstand the frictional forces generated during printing operations,
Fillers can also be mixed. Silicone rubber mixed with filler in advance is commercially available as silicone rubber stock or silicone rubber dispersion, and when it is preferable to obtain a silicone rubber film by coating as in the present invention, RT
(2) Alternatively, LTV silicone rubber dispersion is preferably used. An example of this is Syl Off' 23.5RX-25 manufactured by Toray Silicone.
There are silicone rubber dispersions for paper coating such as 7,5H237.

In general, it is preferable to use condensation and crosslinking type silicone rubber for plate materials.

The silicone rubber layer preferably contains a silane coupling agent having an amino group in order to further improve adhesiveness.

Examples of preferable silane coupling agents include the following.

(a) HzNCIItCHzNII (C1lz)
3si (OCR+) 3(b)II□NCIIzC
IIJH(C1l□)*Si (OCRl)z (Cl
lko) (c) IIJ (CIlg)ssi (OEt
)s Next, the material constituting the photosensitive layer is not particularly limited, and specific examples include the following.

Diazo resins represented by condensates of aromatic diazonium salts and formaldehyde, especially salts of condensates of p-diazodiphenylamine and formaldehyde or acetaldehyde, such as hexafluorophosphates, tetrafluoroborates, perchlorates Or a diazo resin inorganic salt which is a reaction product of a periodate and the above condensate, or a reaction between the above condensate and sulfonic acids as described in U.S. Pat. No. 3,300,309. The product diazo resin organic salt and the like are preferably used.

Further, the diazo resin is preferably used together with a binder, and various polymeric compounds can be used as the binder, but preferably one such as that described in JP-A-54-98613 is used. Monomers having aromatic hydroxyl groups, such as N-(4-hydroxyphenyl)acrylamide, N-(4-hydroxyphenyl)methacrylamide, 0-m-1 or p-hydroxystyrene, 0
-1m, or copolymers of p-hydroxyphenyl methacrylate, etc. and other monomers, and U.S. Patent No. 4.1
Polymers containing hydroxyethyl acrylate units or hydroxyethyl methacrylate units as main repeating units, natural resins such as shellac and rosin, polyvinyl alcohol, and polyvinyl alcohol, as described in U.S. Pat. Polyamide resins such as those described in U.S. Patent No. 257, US Pat.
660,097, linear polyurethane resins, polyvinyl alcohol phthalate resins, epoxy resins condensed from bisphenol A and epichlorohydrin, cellulose derivatives such as cellulose acetate and cellulose acetate phthalate. be done.

Furthermore, a -CH group is added to the main chain or side chain of the polymer as a photosensitive group.
Examples include those whose main component is a photosensitive polymer such as polyesters, polyamides, and polycarbonates containing =CH-C-6 For example, phenylene as described in JP-A-55-40415. Photosensitive polyesters obtained by condensation of diethyl acrylate with hydrogenated bisphenol A and triethylene glycol, such as cinnamylidenemalonic acid, as described in U.S. Pat. No. 2,956,878; Examples include photosensitive polyesters derived from (2-properidene) malonic acid compounds and difunctional glycols.

Furthermore, aromatic azide compounds in which the azide group is bonded directly or via a carbonyl group or a sulfonyl group to an aromatic ring may also be mentioned.For example, U.S. Pat.
Polyazidostyrene, polyvinyl-p-azidobenzoate, polyvinyl-p-azidobenzal as described in No. 311, azidoarylsulfanyl chloride as described in Japanese Patent Publication No. 45-9613, and Reaction products with saturated hydrocarbon polymers, and Japanese Patent Publication Nos. 43-21067 and 44-2295
Polymers having sulfonyl azide or carbonyl azide as described in Japanese Patent No. 4 and Japanese Patent No. 45-24915 can be mentioned.

Photopolymerizable compositions of plate materials suitable for development with the developer of the present invention are disclosed in JP-A-50-50102 and JP-A-55.
-124149, JP-A-61-67864, and JP-A-63-280250, photopolymerizable compositions containing an addition polymerizable unsaturated compound and a photopolymerization initiator are also preferred. It is the material.

Also, JP-A-53-120799, JP-A-62-21
Photocationic polymerization initiators such as diallyliodonium salts, triallylsulfonium salts, and metallocene compounds described in publications such as No. 150 and JP-A-63-17840, and epoxy resins such as bisphenol A-based epoxy resins and alicyclic polyepoxides. It is also possible to use photosensitive compositions containing.

Further, a binder is preferably added to the photopolymerizable composition containing the photosensitive polymer or addition polymerizable unsaturated compound having a photosensitive group as described above. As this binder, the binders mentioned above as those used in combination with the diazo resin can be used, and more preferably, JP-B-49-17874, JP-A-59-46643, JP-A-57- Photocrosslinkable copolymers having ethylenically unsaturated bonds in side chains, which are described in publications such as No. 71048, are used, such as copolymer resins of allyl methacrylate and methacrylic acid, styrene/maleic anhydride, etc. Examples include a carboxylic acid half ester polymer obtained by reacting a copolymer with pentaerythritol triacrylate, and a polymer obtained by adding glycidyl methacrylate to a styrene/acrylonitrile/acrylic acid copolymer.

Photosensitive compositions of plate materials suitable for development with the developer of the present invention include photosensitive compositions containing a binder as described above, such as compositions containing a diazo resin and a binder, and addition-polymerizable compositions. Examples include compositions containing an unsaturated compound, a photopolymerization initiator, and a binder.

The photosensitive composition comprising the above-mentioned components is applied to a support for plate material, and this support must have flexibility that can be used in a normal lithographic printing machine, and be able to withstand the load applied during printing. It is preferable that the material is durable, such as fully flexural plates of aluminum, zinc, copper, steel, etc., metal plates plated or vapor-deposited with chromium, zinc, copper, nickel, aluminum, iron, etc., paper, plastic films, and Examples include glass plates, resin-coated paper, and paper covered with metal foil such as aluminum.

Among these, aluminum plates are particularly preferred.

In order to improve the adhesion between the support and the photosensitive layer, various surface roughening treatments and the like are performed as necessary.

Further, a primer layer may be provided on the support, and examples of materials constituting this primer layer include polyester resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, vinyl chloride resin, polyamide resin, polyvinyl butyral resin. , epoxy resin, acrylate copolymer,
Examples include vinyl acetate copolymers, phenoxy resins, polyurethane resins, polycarbonate resins, polyacrylonitrile butadiene, and polyvinyl acetate. This primer layer may contain an ultraviolet absorber to prevent halation.

Further, as the anchor agent constituting the primer layer, for example, a silane coupling agent, a silicone primer, etc. can be used, and organic titanates and the like are also effective.

The thickness of each layer constituting the plate material as described above is as follows. That is, the support has a thickness of 50 to 400 μm, preferably 100 to 300 μm, and the photosensitive layer has a thickness of 0.05 to 10 μm.
Preferably 0.2 to 5 μm, and the ink anti-abrasive layer is 0.1-1
0 μm, preferably 0.3 to 3 μm.

The plate material may have a protective layer on the top surface of the ink repellent layer, if necessary.

Next, a method for producing a printing plate that does not require dampening water using a plate material that does not require dampening water will be described.

A positive film, which is an original, is vacuum-adhered to the surface of a positive plate material and exposed. The light sources for this exposure include mercury lamps, carbon arc lamps, xenon lamps, etc., which generate abundant ultraviolet rays.
Metal halide lamps, fluorescent lamps, etc. are used.

Then, the positive film 1 is peeled off and developed using the developer of the present invention. In this case, dyes such as crystal violet and astrazone red can be added to the developer to dye the image area at the same time as development.

Development can be carried out by a known method, for example, by rubbing with a developing pad containing a developer as described above, or by pouring the developer onto the printing plate and then rubbing with a developing brush.

By the above development, the ink repellent layer in the unexposed areas is removed and the photosensitive layer, optionally the primer layer or the support, is exposed, and as a result, a printing plate is obtained in which the ink repellent layer remains in the exposed areas.

When silicone rubber is used as the ink-repellent layer, the developer of the present invention is particularly suitable for development methods in which the ink-repellent layer and photosensitive layer in unexposed areas are removed during development, thereby exposing the primer layer or support. Preferably applied.

〔Example〕

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

Note that "parts" described in the examples mean "parts by weight J" unless otherwise specified.

Production of aluminum plate a: An aluminum plate with a thickness of 0.2 mm is degreased by immersing it in a 3% aqueous sodium hydroxide solution, washed with water, and then soaked in hydrochloric acid with a concentration of 1%.
and at a temperature of 25°C in an aqueous solution with a boric acid concentration of 1%.
Electrolytic etching was performed for 5 minutes at 3A/dm'',
After washing with water, 1.
Anodize for 2 minutes at 5A/dm, wash with water,
3 in a 1% aqueous sodium metasilicate solution at a temperature of 85-"C.
It was immersed for 7 seconds, further immersed in water (pH 8.5) at a temperature of 90°C for 25 seconds, washed with water, and dried to obtain an aluminum plate a.

Synthesis of Diazo Resin (1) 14.5 g (50 mmol) of p-diazodiphenylamine sulfate was dissolved in 40.9 g of concentrated sulfuric acid under water cooling.

To this reaction solution, 1.5 g (50 mmol) of rose formaldehyde was slowly added dropwise. At this time, the reaction temperature was 10
The temperature was added so as not to exceed ℃. Thereafter, stirring was continued for 12 hours while cooling with water.

This reaction mixture was cooled with water at 500mj! was added dropwise to ethanol, and the resulting precipitate was filtered. After washing with ethanol,
This precipitate was dissolved in 100ml of pure water and 1. 6 in this liquid
．． A cold concentrated aqueous solution of 8 g of zinc chloride was added. The resulting precipitate was filtered and washed with ethanol.
It was dissolved in 0mf pure water. To this liquid was added a cold concentrated aqueous solution in which 8 g of ammonium hexafluorophosphate was dissolved. The resulting precipitate was collected by filtration, washed with water, and then dried at 30°C for one day and night to obtain diazo resin (1).

Synthesis of polymer compound (1) N-(4-hydroxyphenyl) methacrylamide 53
．． 2g, acrylonitrile 15.9g, ethyl acrylate 36.5g, methyl methacrylate 3.5g and azobisisobutyronitrile 1.642g in acetone-ethanol 1:1 (volume ratio) mixed solvent 112mj! After dissolving the mixture in the solution and purging it with nitrogen, it was heated at 60'C for 8 hours.

After the reaction is completed, the reaction solution is poured into water 51 with stirring, and the resulting white precipitate is filtered and dried to obtain the lipophilic polymer compound (1).
90g of was obtained.

When the molecular weight of this lipophilic polymer compound (1) was measured by GPC, the weight average molecular weight was 52,000.

Next, using the diazo resin (1) and polymer compound (1) produced as described above, a photosensitive composition having the following composition was applied to the aluminum plate a, and io
It was dried for 2 minutes at o'c to form a photosensitive layer with a thickness of 0.5 μm.

(Photosensitive composition) Diazo resin (1) 40 parts Animal skeleton compound (1) 60 parts Victoria Pure Blue BOH 1 part (manufactured by Odugaya Chemical Co., Ltd., dye) Methyl cellosolve 900 parts Then, the following silicone rubber was applied on the photosensitive layer. Composition by dry weight 2
．． It was coated at a concentration of 0 g/m'' and dried at 90° C. for 10 minutes to obtain a lithographic printing plate material that does not require dampening water.

[Silicone rubber layer composition] Dimethylpolysiloxane having hydroxyl groups at both ends (molecular weight 52,000) l 0 parts triacetoxymethylsilane 10 parts dibutyltin laurate 0.8 parts Isopar G
(manufactured by Esso Chemical Co., Ltd.) 900 copies After a positive film was vacuum-adhered to the upper surface of the above plate material, it was exposed to light using a metal halide lamp as a light source, and then developed using the following developer.

During development, the unexposed portions of the photosensitive layer and silicone rubber layer were removed by rubbing the surface of the plate material with a development pad.

[Developer composition]

Isopar 11 20 parts 4-methyl-1,3-dioxolan 2-one 40 parts tripropylene glycol monomethyl ether 35 parts diethyl acid (5 parts)
When printing was performed using a printing machine with the dampening water device removed, 17,000 prints with good dot reproducibility were obtained.

Example 2 A plate material produced in the same manner as in Example 1 was exposed in the same manner as in Example 1, and then developed with the following developer to obtain a lithographic printing plate that did not require dampening water.

[Developer composition] Perex NBL (anionic surfactant, manufactured by Kao Corporation) 3 parts 4-methyl-1,3
-Dioxolan-2-one IO part 3-methyl-3-methoxybutanol 10 parts Diethyl acid (2 parts water)
When 75 copies were printed using the above printing plate, there were a few prints with excellent dot reproducibility.
I got a million pieces.

Comparative Example 1 The procedure of Example 1 was repeated with the only difference that a developer having the following composition was used.

[Developer composition]

20 parts of Isopar H 75 parts of tripropylene glycol monomethyl ether 5 parts of diethyl succinate The resulting printed matter had poor dot reproducibility.

Comparative Example 2 The procedure of Example 1 was repeated with the only difference that a developer having the following composition was used.

[Developer composition] Isopar 1 (40 parts tripropylene glycol monomethyl ether 55 parts diethyl succinate 5 parts The layer was scratched.

Comparative Example 3 The procedure of Example 1 was repeated with the only difference that a developer having the following composition was used.

[Developer composition]

Perex NBL 3 parts diethylene glycol dimethyl ether 10 parts 3-methyl-3-methoxybutanol 10 parts diethyl succinate 2 parts water
75 parts When this developer was used, the development speed was slow, and the resulting printed matter had poor dot reproducibility.

〔Effect of the invention〕

As is clear from the above description, according to the present invention,
Provided is a developer which is suitable for developing lithographic printing plate materials that do not require warm water, has excellent developability, and has good halftone reproducibility.

Claims (1)

[Scope of Claims] A developer for lithographic printing plate materials that does not require dampening water and is characterized by containing one or more compounds represented by the following general formula I. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ I [In the formula, Y represents hydrogen, an alkyl group, or a phenyl group. ]