JP2607158B2 - Photosensitive composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a photosensitive composition, and more particularly to a photosensitive composition suitably used for a photosensitive lithographic printing plate. More specifically, the present invention relates to a photosensitive composition containing a novel diazo resin free of printing stains of the present invention.

[Conventional technology and problems to be solved]

Conventionally, the majority of the materials used as a photosensitive material in pre-sensitized printing materials (so-called PS plates) that act as a negative type are diazonium compounds, and in particular, two or more diazonium salt skeletons are linked. It is a polymer diazonium salt (so-called diazo resin).

When such a diazo resin is coated on a suitable support such as paper, plastic or metal and exposed to actinic light through a transparent negative, the exposed portion of the diazo resin undergoes decomposition to become insoluble and lipophilic. Change.

On the other hand, by dissolving and removing the unexposed portions with water, the surface of the support is exposed. If a support having a surface previously subjected to a hydrophilic treatment is used, the unexposed portion exposes the hydrophilic layer by development. Therefore, when performing offset printing,
This part receives water and repels the ink.

On the other hand, the decomposed portion of the diazo resin exhibits lipophilicity and repels water to accept ink. That is, such a printing material gives a so-called negative-positive printing plate.

In such a diazo resin, as a conventional method of linking a diazonium salt skeleton, an aromatic diazonium compound and an organic condensing agent containing a reactive carbonyl group, particularly formaldehyde, an aldehyde such as acetaldehyde or an acetal are condensed in an acidic medium. A way to let it be used.

The most typical one is a formaldehyde condensate of 4-diazodiphenylamine. The method for producing a diazo resin by the conjugation method is described in, for example, U.S. Pat.Nos. 2,679,498, 3,050,502, 3,311,605, and 3,277,074.
It is described in the specification of the issue.

In the diazo resin linked by the reactive carbonyl group, when the counter anion of the diazonium salt is a mineral acid such as hydrochloric acid, hydrobromic acid, sulfuric acid and phosphoric acid, or an inorganic anion such as a double salt with zinc chloride, water-soluble In this case, there is a problem that the composition becomes unstable to moisture and storage stability is deteriorated. Therefore, in order to improve the storage stability, a water-soluble diazo resin is used as a water-insoluble resin by reacting with a phenolic hydroxyl group-containing aromatic compound, an organic coupling agent such as an acidic aromatic compound or an acidic aliphatic compound. The method is Tokujin Sho 47
No. 1167, US Pat. No. 3,300,309.

However, this type of diazo resin is an alcohol,
Poor solubility in organic coating solvents such as ketones and glycol ethers. Therefore, in order to make the diazo resin water-insoluble and organic solvent-soluble, a diazo resin having a counter anion of a halogenated Lewis acid such as tetrafluoroboric acid and hexafluorophosphoric acid, and a perhalic acid such as perchloric acid and periodic acid is used. Use of resin JP-A-54-98
Nos. 613 and 56-121031.

Further, regarding the use of an anionic surfactant, that is, a diazo resin having a sulfonic acid having a long-chain alkyl group as a counter anion, JP-A-58-209733 and JP-A-62-175731.
And JP-A-63-262643.

However, since these diazo resins are essentially insoluble in alkaline water, the diazo resin is not sufficiently removed during alkali development, and a residual film is formed on an unexposed portion, and as a result,
There is a problem that printing stains occur.

[Problems to be solved by the invention]

Therefore, an object of the present invention is to provide a photosensitive composition containing a novel diazo resin free of printing stains.
That is, an object of the present invention is to provide a photosensitive composition containing a diazo resin, which has improved developability when non-image areas are alkali-developed after image exposure and does not cause printing stains.

Another object of the present invention is to provide a photosensitive composition containing a diazo resin which can be produced at low cost and has excellent production suitability.

Yet another object of the present invention is to provide a photosensitive composition containing a diazo resin having improved solubility in an organic solvent and improved storage stability.

[Means for solving the problem]

The present inventors have made intensive studies to achieve the above object, and as a result, have found that the use of a novel diazo resin achieves the above object, thereby achieving the present invention.

That is, the present invention provides a photosensitive composition containing a diazo resin and an organic solvent-soluble polymer compound, wherein the diazo resin is a condensate of an aromatic diazonium compound and an aldehyde having a sulfonic acid group or an equivalent thereof. It is intended to provide a photosensitive composition characterized by the following. The sulfonic acid group may form an internal salt in the diazo resin.

 Hereinafter, the present invention will be described in detail.

The diazo resin of the present invention is synthesized by a condensation reaction between an aromatic diazonium compound and an aldehyde having a sulfonic acid group or an equivalent thereof.
For example, a diazo monomer having a 4-diazodiphenylamine skeleton, a 4-diazodiphenylether skeleton or a 4-diazodiphenylsulfide skeleton and an aldehyde having a sulfonic acid group or an acetal thereof are preferably each at a molar ratio of 1:10 to 1: Examples of the method include condensation in an acidic medium at a ratio of 0.05, more preferably 1: 2 to 1: 0.2. When performing the condensation reaction, in order to adjust the sulfonic acid content and molecular weight of the resulting diazo resin, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, iso-butyraldehyde, benzaldehyde, acetone, methyl ethyl ketone or acetophenone An active carbonyl compound having no sulfonic acid group or an acetal thereof can be used in combination as a condensing agent. As the active carbonyl compound having no sulfonic acid group, formaldehyde is most preferred, and its charge ratio is preferably 0 to 5, more preferably 0.1 to 5 in terms of molar ratio to the diazo monomer.
~ 1. When an aldehyde having a sulfonic acid group and an active carbonyl compound having no sulfonic acid group are used in combination, first, a diazo monomer and an aldehyde having a sulfonic acid group are condensed in an acidic medium. By performing post-condensation using a highly reactive, for example, active carbonyl compound having no sulfonic acid group such as formaldehyde or an acetal thereof, a higher molecular weight diazo resin can be obtained.

Further, in place of the above-mentioned active carbonyl compound having no sulfonic acid group or their acetal,
Methylol derivatives as described in JP-A-49-45322 and JP-A-49-45323 or olefinically unsaturated compounds as described in JP-A-58-187925 can also be used.

The diazo monomer according to the present invention is a compound having an aromatic ring substituted with at least one diazonium group, and preferably includes an aromatic diazo compound represented by the following general formula (I).

In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a hydroxyl group, a carboxyester group or a carboxyl group, preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms. , An alkoxy group having 1 to 3 carbon atoms or a hydroxyl group.

R ² represents a hydrogen atom, an alkyl group or an alkoxy group,
Preferably, it represents a hydrogen atom or an alkoxy group having 1 to 3 carbon atoms.

R ³ represents a hydrogen atom, an alkyl group or an alkoxy group,
Preferably, it represents a hydrogen atom or an alkoxy group having 1 to 3 carbon atoms.

X ⁻ represents an anion, preferably an anion of an inorganic or organic acid having a pKa of 4 or less.

Specifically, hydrohalic acid, for example, hydrofluoric acid,
Hydrochloric acid, hydrochloric acid-zinc chloride complex, hydrobromic acid; sulfuric acid, nitric acid, phosphoric acid (pentavalent phosphorus), especially orthophosphoric acid, inorganic iso- and heteropolyacids such as phosphotungstic acid, phosphomolybdic acid , Aliphatic or aromatic phosphonic acids or half esters thereof, arsonic acid, phosphinic acid, fluorocarboxylic acids such as trifluoroacetic acid, amide sulfonic acid, selenic acid, hydroboronic acid, hexafluorophosphoric acid, perchloric acid, Further, there may be mentioned anions such as aliphatic and aromatic sulfonic acids.

Y represents -NH-, -O-, or -S-, and preferably represents -NH-.

Specific examples of the aromatic diazo compound represented by the general formula (I) include, for example, 4-diazodiphenylamine,
4'-hydroxy-4-diazodiphenylamine, 4 '
-Methoxy-4-diazodiphenylamine, 4'-ethoxy-4-diazodiphenylamine, 4'-n-propoxy-4-diazodiphenylamine, 4'-i-propoxy-4-diazodiphenylamine, 4'-methyl-4
-Diazodiphenylamine, 4'-ethyl-4-diazodiphenylamine, 4'-n-propyl-4-diazodiphenylamine, 4'-i-propyl-4-diazodiphenylamine, 4'-n-butyl-4-diazodiphenylamine, 4'-hydroxymethyl-4-diazodiphenylamine, 4'-β-hydroxyethyl-4-diazodiphenylamine, 4'-γ-hydroxypropyl-4
-Diazodiphenylamine, 4'-methoxymethyl-4
-Diazodiphenylamine, 4'-ethoxymethyl-4
-Diazodiphenylamine, 4'-β-methoxyethyl-4-diazodiphenylamine, 4'-β-ethoxyethyl-4-diazodiphenylamine, 4'-carbomethoxy-4-diazodiphenylamine, 4'-carbethoxy-4-diazo Diphenylamine, 4'-carboxy-4-diazodiphenylamine, 4-diazo-3-methoxy-diphenylamine, 4-diazo-2-methoxydiphenylamine, 2'-methoxy-4-diazodiphenylamine, 3-methyl-4-diazodiphenylamine,
3-ethyl-4-diazodiphenylamine, 3'-methyl-4-diazodiphenylamine, 3-ethoxy-4-
Diazodiphenylamine, 3-hexyloxy-4-diazodiphenylamine, 3-β-hydroxyethoxy-4
-Diazodiphenylamine, 2-methoxy-5'-methyl-4-diazodiphenylamine, 4-diazo-3-methoxy-6-methyldiphenylamine, 3,3'-dimethyl-4-diazodiphenylamine, 3'-n-butoxy- 4-diazodiphenylamine, 3,4'-dimethoxy-
4-diazodiphenylamine, 2'-carboxy-4-
Diazodiphenylamine, 4-diazodiphenylether, 4'-methoxy-4-diazodiphenylether,
4'-methyl-4-diazodiphenyl ether, 3,4 '
-Dimethoxy-4-diazodiphenyl ether, 4'-
Carboxy-4-diazodiphenyl ether, 3,3'-
Dimethyl-4-diazodiphenyl ether, 4-diazodiphenyl sulfide, 4'-methyl-4-diazodiphenyl sulfide, 4'-methyl-2,5-dimethoxy-
4-diazodiphenyl sulfide and the like.

Among them, particularly preferred aromatic diazo compounds include 4-diazodiphenylamine and 4-diazo-4'-.
Examples include methoxydiphenylamine, 4-diazo-4'-ethoxydiphenylamine, and 4-diazo-3-methoxydiphenylamine.

The aldehyde having a sulfonic acid group or the acetal thereof preferably includes an aldehyde having a structure represented by the following general formula (II) or an acetal thereof.

[Wherein, R ⁴ represents a single bond or a divalent organic group having 1 to 14 carbon atoms which may have a substituent (for example, an aliphatic hydrocarbon group,
An aromatic hydrocarbon group or a heterocyclic group). Examples of the group that can be substituted for R ⁴ include an alkyl group, an aryl group,
Examples include an alkoxy group, an aryloxy group, a halogen atom, a hydroxy group, a substituted or unsubstituted amino group, a carboxyester group, an amide group or a carboxyl group.
Further, R ⁴ may contain, as a linking group, an ether group, an amide group, an ester group, a urethane group, a urea group, a carbonate group, an amino group, or the like in the chain. M represents a hydrogen atom, a metal atom such as sodium, potassium, lithium, cesium, calcium, barium, magnesium, aluminum, zinc, or an unsubstituted or substituted ammonium, and n represents a valence of M. Specific examples of these aldehydes having a sulfonic acid group or acetal thereof include 2-oxo-1-ethanesulfonic acid, 3-oxo-1-propanesulfonic acid, 4-oxo-1-butanesulfonic acid, -Oxo-
1-pentanesulfonic acid, 6-oxo-1-hexanesulfonic acid, 2-formylbenzenesulfonic acid, 3-formylbenzenesulfonic acid, 4-formylbenzenesulfonic acid, 2,2-dimethyl-3-oxo-1-propane Sulfonic acid, 2,3-dimethyl-4-oxo-1-butanesulfonic acid, 2-methyl-6-oxo-1-hexanesulfonic acid, 2-formyl-4-methoxybenzenesulfonic acid, 4-amino-3- Formylbenzenesulfonic acid, 4
-(2-oxoethyl) benzenesulfonic acid, 3- (3
-Oxopropyl) benzenesulfonic acid, 4-formyl-1,3-benzenedisulfonic acid, 2-formyl-1,3-benzenedisulfonic acid, 2-formyl-1-naphthalenesulfonic acid, 4-formyl-1-naphthalenesulfonic acid acid,
5-formyl-2-naphthalenesulfonic acid, 7-formyl-1,4-naphthalenedisulfonic acid, 5-amino-7-
Formyl-2-naphthalenesulfonic acid, 5-formyl-
2-furansulfonic acid, 3-formyl-2-furansulfonic acid, 5-formyl-3-furansulfonic acid, 1-oxo-1-methanesulfonic acid, 4-formylphenoxy-3-propanesulfonic acid, 4-formyl Phenoxy
4-butanesulfonic acid, 3-formylphenoxy-3-
Butanesulfonic acid, p-formyl-N- (2-sulfonylethyl) benzamide, m-formyl-N- (3-sulfonylpropyl) benzamide, p-formylbenzoic acid-2-sulfonylethyl, p-formylbenzoic acid-3
-Sulfonylpropyl, 4-sulfonylbutyl m-formylbenzoate, 2-formylethyl p-sulfonylbenzoate, 3-formylpropyl p-sulfonylbenzoate, m-sulfonylphenyl 3-formylpropionate, N- (2-sulfonylethyl) -3-formylpropionamide, 2-sulfonylethyl 3-formylpropionate, N- (3-sulfonylphenyl) glyoxylate, N- (2-sulfonylethyl) glyoxylate, glyoxylate -2-sulfonylethyl or their acetal.

Of course, these may be free sulfonic acids, metal salts of sulfonic acids such as sodium, potassium, lithium, cesium, calcium, barium, magnesium, aluminum and zinc, or unsubstituted or substituted ammonium salts. Is also good.

Specific examples of the acidic medium used when synthesizing the diazo resin used in the present invention include, for example, strong acids such as hydrochloric acid, phosphoric acid, methanesulfonic acid and sulfuric acid.

These media are at least 30% by weight, preferably 70-100%
Used at a concentration of% by weight. Generally the rest is water,
It may consist partially or completely of an organic solvent, for example methanol, acetic acid, N-methylpyrrolidone and the like. Good results are e.g. 85-93%-phosphoric acid, 80%-sulfuric acid or 90%.
% -Methanesulfonic acid or a mixture of these acids.

The temperature during the condensation is about 0 to 70 ° C, preferably about 5 to 50 ° C.
° C.

The molecular weight of the diazo resin used in the present invention is about
A range of 500 to 100,000 is suitable, preferably about 1,000
It is in the range of ~ 10,000.

The content of the sulfonic acid bonded to the crosslinking group of the diazo resin of the present invention is preferably 0.1 to 5 meq / g, more preferably 0.5 to 3 meq / g. At this time, if the content of the sulfonic acid is too large, the solubility of the diazo resin in the organic solvent becomes low, and if the content of the sulfonic acid is too small, the printing stain is easily generated.

When the content of the sulfonic acid bonded to the crosslinking group of the diazo resin of the present invention is less than 1 equivalent to the diazonium cation, it is necessary to contain an appropriate amount of a counter anion.

The counter anion of the diazo resin used in the present invention includes an anion of an inorganic or organic acid preferably having a pKa of 4 or less, which forms a salt with the diazo resin stably and makes the resin soluble in an organic solvent. These include organic carboxylic acids such as decanoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid and sulfonic acids, and typically include hydrohalic acids such as hydrofluoric acid, hydrochloric acid, Hydrobromic acid; sulfuric acid, nitric acid, phosphoric acid (pentavalent phosphorus), especially orthophosphoric acid, inorganic iso- and heteropolyacids such as phosphotungstic acid, phosphomolybdic acid, aliphatic or aromatic sulfonic acids or half esters thereof , Carboxylic acids such as arsonic acid, phosphinic acid, trifluoroacetic acid, amidosulfonic acid, selenic acid, borofluoric acid, hexafluorophosphoric acid, perchloric acid, and also aliphatic and aromatic sulfonic acids such as methanesulfone Acid, fluoroalkanesulfonic acid such as trifluoromethanesulfonic acid, laurylsulfonic acid, dioctylsulfosuccinic acid, Rohexyl sulfosuccinic acid, camphorsulfonic acid, trioxy-3-propanesulfonic acid, nonylphenoxy-3-propanesulfonic acid, nonylphenoxy-4-butanesulfonic acid, dibutylphenoxy-3-propanesulfonic acid, diamylphenoxy-3- Propanesulfonic acid, dinonylphenoxy-3-propanesulfonic acid, dibutylphenoxy-4-butanesulfonic acid, dinonylphenoxy-4-butanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, mesitylenesulfonic acid, p-chlorobenzenesulfonic acid 2,5-dichlorobenzenesulfonic acid, sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, p-acetylbenzenesulfonic acid, 5-nitro-
o-Toluenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-chloro-5-nitrobenzenesulfonic acid, butylbenzenesulfonic acid, butoxybenzenesulfonic acid, 2-methoxy-4 -Hydroxy-5-benzoylbenzenesulfonic acid, isopropylnaphthalenesulfonic acid, butylnaphthalenesulfonic acid, hexylnaphthalenesulfonic acid, butoxynaphthalenesulfonic acid, dodecyloxynaphthalenesulfonic acid, dibutylnaphthalenesulfonic acid, triisopropylnaphthalenesulfonic acid,
Tributylnaphthalenesulfonic acid, 1-naphthol-5
-Sulfonic acid, naphthalene-1-sulfonic acid, naphthalene-2-sulfonic acid, 1,8-dinitro-naphthalene-3,6
-Disulfonic acid, 4,4'-diazido-stilbene-3,3 '
-Disulfonic acid, 1,2-naphthoquinone-2-diazide-4-sulfonic acid, 1,2-naphthoquinone-2-diazide-5-sulfonic acid, 1,2-naphthoquinone-1-diazide-4-sulfonic acid, octyl Benzenesulfonic acid, dioctylbenzenesulfonic acid, nonylbenzenesulfonic acid, dinonylbenzenesulfonic acid, decylbenzenesulfonic acid, undecylbenzenesulfonic acid, dodecylbenzenesulfonic acid, bis-dodecylbenzenesulfonic acid,
Tridecylbenzenesulfonic acid, undecyloxybenzenesulfonic acid, bis-undecyloxybenzenesulfonic acid, dodecyloxybenzenesulfonic acid, bis-dodecyloxybenzenesulfonic acid, dodecyltoluenesulfonic acid, tetradecylbenzenesulfonic acid, pentadecylbenzene Sulfonic acid, hexadecylbenzene sulfonic acid,
Heptadecylbenzenesulfonic acid, octadecylbenzenesulfonic acid, nonadecylbenzenesulfonic acid, eicosadecylbenzenesulfonic acid, octylnaphthalenesulfonic acid, dioctylnaphthalenesulfonic acid, nonylnaphthalenesulfonic acid, dininolnaphthalenesulfonic acid, decylnaphthalenesulfonic acid, Anions such as bis-decylnaphthalenesulfonic acid, undecylnaphthalenesulfonic acid, dodecylnaphthalenesulfonic acid, and tridecylnaphthalenesulfonic acid, or a mixture of these anions are included.

Particularly preferred among these anions are hexafluorophosphoric acid, methanesulfonic acid, dibutylnaphthalenesulfonic acid, 2-methoxy-4-hydroxy-5-benzoylbenzenesulfonic acid, dodecylbenzenesulfonic acid, and dioctylnaphthalenesulfonic acid. Is an anion.

 Next, a synthesis example of the diazo resin of the present invention will be described.

Synthesis Example 1 2-diazodiphenylamine hydrogen sulfate 29.3 g (0.100 g)
mol) was dissolved in 70 ml of concentrated sulfuric acid. To this, 4- (3-sulfonylpropoxy) benzaldehyde potassium salt 14.1
g (0.0500 mol) was added and stirred at 5 ° C. for 2 hours. Next, add paraformaldehyde (95%) to the reaction mixture.
1.58 g (0.0500 mol) was added, and the mixture was further stirred at 5 ° C. for 2 hours. Thereafter, the reaction solution was diluted with isopropyl alcohol 1
The mixture was poured into the mixture with stirring to precipitate a yellow precipitate.
The yellow precipitate was filtered off and washed with isopropyl alcohol to give 4-diazodiphenylamine and 4-
A hydrogen sulfate of a condensate with (3-sulfonylpropoxy) benzaldehyde formaldehyde was obtained.

The above condensate was dissolved in 400 ml of water, and 20.9 g (0.0600 mol) of sodium n-dodecylbenzenesulfonate was added to water.
The 600 ml solution was added with vigorous stirring. The resulting yellow precipitate was collected by filtration, dried, and dried with 4-diazodiphenylamine and 4- (3-sulfonylpropoxy) benzaldehyde.
39 g of n-dodecylbenzenesulfonate as a condensate with formaldehyde was obtained (diazo resin 1 of the present invention).

The obtained diazo resin was treated with 1-phenyl-3-methyl-5.
-After coupling with pyrazolone, the weight average molecular weight was measured using GPC (gel permeation chromatography) (polystyrene standard) to be 1900.

Synthesis Example 2 2-diazodiphenylamine hydrogen sulfate 29.3 g (0.100 g)
mol) was dissolved in 70 ml of 96% sulfuric acid. To this, 9.31 g (0.0300 g) of benzaldehyde-2,4-disulfonate disodium salt
mol) was added and stirred at 5 ° C. for 2 hours. Next, 2.21 g of paraformaldehyde (95%) was added to the reaction mixture.
(0.0700 mol), and the mixture was further stirred at 5 ° C. for 2 hours. Thereafter, the reaction solution was poured into isopropyl alcohol 1 with stirring to precipitate a yellow precipitate. The yellow precipitate was separated by filtration and washed with isopropyl alcohol to obtain a hydrogen sulfate of a condensate of 4-diazodiphenylamine and benzaldehyde-2,4-disulfonic acid / formaldehyde.

The above condensate was suspended in a mixed solution of 200 ml of water and 500 ml of MEK,
Sodium dioctyl naphthalene sulfonate 22.2
g (0.0480 mol) in 600 ml of water was added with vigorous stirring. After stirring for a while, the mixture was allowed to stand and separated into two layers. The upper layer was poured into water 2 with stirring, and the resulting yellow precipitate was collected by filtration and dried to give dioctylnaphthalenesulfonate, a condensate of 4-diazodiphenylamine and benzaldehyde-2,4-disulfonic acid / formaldehyde. 36 g were obtained (the diazo resin 2 of the present invention).

The obtained diazo resin was treated with 1-phenyl-3-methyl-5.
-After coupling with pyrazolone, the weight average molecular weight was measured using GPC (polystyrene standard).
It was 1800.

Synthesis Example 3 4-diazo-4'-methoxydiphenylamine hydrogen sulfate (32.3 g, 0.100 mol) was dissolved in 96% sulfuric acid. To this, sodium benzaldehyde-4-sulfonate 10.4
g (0.0500 mol) was added and stirred at 5 ° C. for 2 hours. Next, paraformaldehyde (95%) 1.
58 g (0.0500 mol) was added, and the mixture was further stirred at 5 ° C. for 2 hours. Thereafter, the reaction solution was poured into ice water 1.5 with stirring, and 130 g of a 50% aqueous solution of zinc chloride was further added to precipitate a yellow precipitate. The yellow precipitate was separated by filtration to obtain a zinc chloride double salt of a condensate of 4-diazo-4'-methoxydiphenylamine and benzaldehyde-4-sulfonic acid / formaldehyde.

The above condensate was dissolved in 800 ml of water, and a solution of 11.1 g (0.0600 mol) of potassium hexafluorophosphate in 600 ml of water was added thereto with stirring. The resulting yellow precipitate was collected by filtration and dried to obtain 38 g of a hexafluorophosphate salt of a condensate of 4-diazo-4'-methoxydiphenylamine and benzaldehyde-4-sulfonic acid / formaldehyde (the diazo resin 3 of the present invention). ).

The obtained diazo resin was treated with 1-phenyl-3-methyl-5.
-After coupling with pyrazolone, the weight average molecular weight was measured using GPC (polystyrene standard).
It was 50.

Synthesis Example 4 4-diazo-4'-methyldiphenylamine hydrogen sulfate (30.7 g, 0.100 mol) was dissolved in 85% phosphoric acid (70 ml). To this benzaldehyde-2-sodium sulfonate 10.4
g (0.0500 mol) was added and stirred at 40 ° C. for 20 hours. Next, 4.48 g (0.0450mo) of benzaldehyde was added to the reaction mixture.
l) was added and the mixture was further stirred at 40 ° C for 20 hours. afterwards,
The reaction solution was poured into 1.5 parts of ice water with stirring, and 130 g of a 50% aqueous solution of zinc chloride was further added to precipitate a yellow precipitate. The yellow precipitate was separated by filtration to obtain a zinc chloride double salt of a condensate of 4-diazo-4'-methyldiphenylamine and benzaldehyde / benzaldehyde-2-sulfonic acid.

The above condensate was suspended in a mixed solution of 200 ml of water and 500 ml of MEK,
Sodium n-dodecylbenzenesulfonate 20.9
g (0.0600 mol) in 600 ml of water was added with vigorous stirring. After stirring for a while, the mixture was allowed to stand and separated into two layers. This upper layer was poured into water 2 with stirring, and the resulting yellow precipitate was collected by filtration and dried to give 4-diazo-4'-methyldiphenylamine and benzaldehyde.
An n-dodecylbenzenesulfonic acid salt of a condensate with benzaldehyde-2-sulfonic acid was obtained (diazo resin 4 of the present invention).

The obtained diazo resin was treated with 1-phenyl-3-methyl-5.
-After coupling with pyrazolone, the weight average molecular weight was measured using GPC (polystyrene standard) to be 1800.

Synthesis Example 5 4-diazodiphenylamine hydrogen sulfate 29.3 g (0.100 g)
mol) was dissolved in 70 ml of 96% sulfuric acid. To this, 8.71 g (0.0500 ml) of sodium 4-oxobutane-1-sulfonate
Was added and stirred at 5 ° C. for 2 hours. Next, 1.90 g (0.0600 m) of paraformaldehyde (95%) was added to the reaction mixture.
ol) and stirred at 5 ° C. for a further 2 hours. afterwards,
The reaction solution was poured into 1.5 parts of ice water while stirring, and 130 g of a 50% aqueous solution of zinc chloride was further added to precipitate a yellow precipitate. The yellow precipitate was separated by filtration to obtain a zinc chloride double salt of a condensate of 4-diazodiphenylamine and 4-oxobutane-1-sulfonic acid / formaldehyde.

The above condensate was suspended in a mixed solution of 200 ml of water and 500 ml of MEK,
To this, sodium dioctylnaphthalenesulfonate 27.7
g (0.0600 mol) in 600 ml of water was added with vigorous stirring. After stirring for a while, the mixture was allowed to stand and separated into two layers. The upper layer was poured into water 2 with stirring, and the resulting yellow precipitate was collected by filtration and dried to give 4-diazodiphenylamine and 4-oxobutane-1-sulfonic acid.
37 g of dioctylnaphthalenesulfonic acid salt of a condensate with formaldehyde was obtained (diazo resin 5 of the present invention).

The obtained diazo resin was treated with 1-phenyl-3-methyl-5.
-After coupling with pyrazolone, the weight average molecular weight was measured using GPC (polystyrene standard).
2080.

The diazo resin of the present invention is desirably used in combination with an alkali-soluble or swellable lipophilic polymer compound used as a binder resin.

As the lipophilic polymer compound, the following (1) to (1)
Copolymers having a molecular weight of usually from 20,000 to 200,000 using the monomer shown in 4) as a structural unit are exemplified.

(1) Acrylamides, methacrylamides, acrylates, methacrylates and hydroxystyrenes having an aromatic hydroxyl group, for example, N- (4
-Hydroxyphenyl) acrylamide or N- (4-
(Hydroxyphenyl) methacrylamide, o-, m-, p-
Hydroxyphenyl-acrylate or methacrylate, o-, m-, p-hydroxystyrene, (2) acrylates having an aliphatic hydroxyl group,
And methacrylic esters such as 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate, (3) acrylic acid, methacrylic acid, maleic anhydride,
Unsaturated carboxylic acids such as itaconic acid, (4) methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate,
(Substituted) alkyl acrylates such as hexyl acrylate, octyl acrylate, 2-chloroethyl acrylate, glycidyl acrylate, N-dimethylaminoethyl acrylate, (5) methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate,
(Substituted) alkyl methacrylates such as amyl methacrylate, cyclohexyl methacrylate, 4-hydroxybutyl methacrylate, glycidyl methacrylate, N-dimethylaminoethyl methacrylate, (6) acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N- Acrylamide or methacrylamides such as ethylacrylamide, N-hexylmethacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide, N-ethyl-N-phenylacrylamide; Ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl Vinyl ethers such as nyl ether, butyl vinyl ether, octyl vinyl ether and phenyl vinyl ether; (8) vinyl acetate, vinyl chloroacetate,
Vinyl esters such as vinyl butyrate and vinyl benzoate; (9) styrenes such as styrene, α-methyl styrene, methyl styrene and chloromethyl styrene; (10) methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl Vinyl ketones such as vinyl ketone, (11) olefins such as ethylene, propylene, isobutylene, butadiene, isoprene, (12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile, etc. 13) unsaturated imides such as maleimide, N-acryloylacrylamide, N-acetylmethacrylamide, N-propionylmethacrylamide, N- (p-chlorobenzoyl) methacrylamide, (14) m-aminosulfonylphenyl methacryl Over DOO, N-(p-aminosulfonylphenyl) methacrylamide, N-(p-aminosulfonylphenyl) acrylamide, N-(p-toluenesulfonyl) unsaturated sulfonamides such as methacrylamide.

Further, a monomer copolymerizable with the above monomer may be copolymerized. Further, a copolymer obtained by copolymerization of the above monomers, for example, glycidyl methacrylate,
Examples include those modified with glycidyl acrylate and the like, but are not limited thereto.

Particularly preferred lipophilic polymer compounds are acrylic acid,
Copolymer containing methacrylic acid, crotonic acid or maleic acid as an essential component, for example, 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate, acrylonitrile or methacrylonitrile as described in JP-A-50-118802 A multi-component copolymer of acrylic acid or methacrylic acid and, if necessary, another copolymerizable monomer, a terminal having a hydroxy group as described in JP-A-53-120903, and a dicarboxylic acid A multi-component copolymer of acrylic acid or methacrylic acid, acrylic acid, or methacrylic acid esterified with a group containing an ester residue and optionally other copolymerizable monomers, JP-A-54-98614 (E.g., N- (4-hydroxyphenyl) methacrylic monomer having an aromatic hydroxyl group as described in Amide), acrylic acid or methacrylic acid and, if necessary, a multi-component copolymer with other copolymerizable monomers, alkyl acrylate, acrylonitrile or methacryloyl as described in JP-A-56-4144. A multi-component copolymer comprising a nitrile and an unsaturated carboxylic acid can be mentioned. In addition, acidic polyvinyl alcohol derivatives and acidic cellulose derivatives are also useful. JP-B-54-19773, JP-A-57-94747, JP-A-60-1882437, JP-A-62-58242, and JP-A-62-58242 in which polyvinyl acetal or polyurethane is alkali-solubilized.
The polymer compounds described in JP-A-123453 are also useful.

These lipophilic polymer compounds may be used alone or as a mixture.

If necessary, a polyvinyl butyral resin, a polyurethane resin, a polyamide resin, an epoxy resin, a novolak resin, a natural resin, or the like may be added.

The lipophilic polymer compound used in the present invention is usually contained in the solid content of the photosensitive composition at 40 to 99% by weight, preferably 50 to 95% by weight. The photosensitive diazo resin used in the present invention is usually contained in an amount of 1 to 60% by weight, preferably 3 to 30% by weight.

 Next, a synthesis example of the lipophilic polymer compound will be described.

(Synthesis of Lipophilic Polymer Compound 1) N- (4-hydroxyphenyl) methacrylamide 18
g, acrylonitrile 13 g, ethyl acrylate 66 g, methacrylic acid 8.6 g and azobisisobutyronitrile 1.64
Dissolve 2 g of acetone-methanol 1: 1 mixed solution 112 ml,
After purging with nitrogen, the mixture was heated at 60 ° C. for 8 hours.

After completion of the reaction, the reaction solution was poured into water 5 with stirring, and the resulting white precipitate was collected by filtration and dried to obtain 88 g of lipophilic polymer compound 1.

When the molecular weight of this lipophilic polymer compound 1 was measured by GPC, the weight average molecular weight was 75,000.

(Synthesis of Lipophilic Polymer Compound 2) A mixture of 50.0 g of 2-hydroxyethyl methacrylate, 20 g of acrylonitrile, 25 g of methyl methacrylate, and 5 g of methacrylic acid and 1.2 g of benzoyl peroxide was heated at 100 ° C. to 300 g of ethylene glycol monomethyl ether. To 2
It was dropped over time. After completion of the dropwise addition, 300 g of ethylene glycol monomethyl ether and 0.3 g of benzoyl peroxide were added, and the mixture was allowed to react for 4 hours. After completion of the reaction, the mixture was diluted with methanol and poured into water 5 with stirring. The resulting white precipitate was collected by filtration and dried to obtain 90 g of lipophilic polymer compound 2.

When the molecular weight of this lipophilic polymer compound 2 was measured by GPC, the weight average molecular weight was 65,000.

(Synthesis of Lipophilic Polymer Compound 3) 2-hydroxyethyl methacrylate 45 g, acrylonitrile 10 g, ethyl methacrylate 35 g, methacrylic acid
A mixture of 10 g and 1.2 g of benzoyl peroxide was dropped into ethylene glycol monomethyl ether in the same manner as in the synthesis of lipophilic polymer compound 2, to obtain 90 g of lipophilic polymer compound 3.

When the molecular weight of this lipophilic polymer compound 3 was measured by GPC, the weight average molecular weight was 62,000.

Various additives can be further added to the photosensitive composition used in the present invention.

For example, alkyl ethers (eg, ethylcellulose, methylcellulose) for improving coatability, surfactants (eg, fluorine-based surfactants), film flexibility,
Plasticizer for imparting abrasion resistance (for example, tricresyl phosphate, dimethyl phthalate, dibutyl phthalate, trioctyl phosphate, tributyl phosphate, tributyl citrate, polyethylene glycol, polypropylene glycol, etc.), and the image area of the developer are visible Pigments such as acridine dyes, cyanine dyes, styryl dyes, triphenylmethane dyes and phthalocyanines and other general stabilizers for diazo resins (phosphoric acid, phosphorous acid, pyrophosphoric acid, oxalic acid, Boric acid, p-toluenesulfonic acid, benzenesulfonic acid, p-hydroxybenzenesulfonic acid, 2-methoxy-4-hydroxy-5
-Benzoylbenzenesulfonic acid, malic acid, tartaric acid,
Dipicolinic acid, polyacrylic acid and its copolymer, polyvinylphosphonic acid and its copolymer, polyvinylsulfonic acid and its copolymer, 5-nitronaphthalene-1-phosphonic acid, 4-chlorophenoxymethylphosphonic acid, sodium phenyl- Methyl-pyrazolone sulfonate,
2-phosphonobutane-1,2,4-tricarboxylic acid, 1-phosphonoethane-1,2,2-tricarboxylic acid, 1-hydroxyethane-1,1-disulfonic acid, etc.) can be added. The amount of these additives varies depending on the intended use, but is generally 0.1% based on the total solid content of the photosensitive layer.
It is 1 to 30% by weight.

The photosensitive composition of the present invention is dissolved in a suitable organic solvent, and the dry coating weight is 0.2 to 10 g / m on a support having a lipophilic surface.
² to obtain a photosensitive lithographic printing plate. The concentration of the photosensitive composition at the time of application is desirably in the range of 1 to 50% by weight. Examples of the coating solvent used include methyl cellosolve, ethyl cellosolve, 1-methoxy-2-propanol, dimethoxyethane, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, methyl cellosolve acetate, acetone, methyl ethyl ketone, methanol, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide. Examples include side, methyl lactate, ethyl lactate, ethylene dichloride, cyclohexanone, dioxane, and tetrahydrofuran. A mixed solvent obtained by adding a mixed solvent thereof or a solvent which does not dissolve a small amount of water or a diazo resin such as toluene or a high molecular compound to the mixed solvent or the mixed solvent is also suitable. When a photosensitive solution dissolved in these solvents is applied to a support and dried, it is preferable to dry at 50 ° C to 120 ° C. The drying may be carried out at a low temperature at the beginning, followed by preliminary drying, followed by drying at a high temperature. Alternatively, drying may be carried out directly at a high temperature by selecting an appropriate solvent and concentration.

As a support on which the photosensitive composition of the present invention is applied,
Various materials such as paper, plastic, and metal are used. When used for a photosensitive lithographic printing plate, an aluminum plate subjected to a hydrophilization treatment is particularly preferable. The surface of the aluminum plate is made by mechanical methods such as wire brush graining, brush graining by pouring a slurry of abrasive particles with a nylon brush, and ball graining, and HF and AlCl.
₃ , Chemical graining with HCl as an etchant,
After graining the surface by electrolytic graining using nitric acid or hydrochloric acid as an electrolytic solution or composite graining performed by combining these surface roughening methods, etching is performed with an acid or alkali as necessary, and subsequently It is preferable that anodizing is performed in a sulfuric acid, a phosphoric acid, an oxalic acid, a boric acid, a chromic acid, a sulfamic acid or a mixed acid thereof with a direct current or an alternating current power supply to provide a strong passivation film on the aluminum surface.
Although the aluminum surface is hydrophilized by such a passivation film itself, furthermore, if necessary, US Pat. No. 2,714,066
Silicate treatment (sodium silicate, potassium silicate) described in U.S. Pat. No. 3,181,461 and US Pat. No. 3,181,461; potassium fluorozirconate treatment described in U.S. Pat. No. 2,946,638; U.S. Pat. No. 3,201,24
No. 7, phosphomolybdate treatment,
Alkyl titanate treatment described in British Patent No. 1,108,559, polyacrylic acid treatment described in German Patent 1,091,433, German Patent 1,134,093 and British Patent 1,230,447 Polyvinylphosphonic acid treatment, phosphonic acid treatment described in JP-B-44-6409, phytic acid treatment described in U.S. Patent No. 3,307,951, JP-A-58-16.
No. 893 or JP-A-58-18291, treatment with a salt of a hydrophilic organic polymer compound and a divalent metal,
Those which have been subjected to a hydrophilization treatment by undercoating a water-soluble polymer having a sulfonic acid group described in JP-A-59-101651 are particularly preferred. As another hydrophilic treatment method, silicate electrodeposition described in US Pat. No. 3,658,662 can also be mentioned.

Further, after graining treatment and anodic oxidation, sealing treatment is also preferable. Such a sealing treatment is performed by immersion in hot water and a hot aqueous solution containing an inorganic salt or an organic salt, a steam bath, or the like.

The photosensitive composition of the present invention coated on a support is exposed through a transparent original having a line image, a halftone dot image, and the like, and then developed with an aqueous alkaline developer to form a negative relief image on the original. give.

Light sources suitable for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, strobes, ultraviolet rays, laser beams and the like.

The developer used for the development of the photosensitive printing plate according to the present invention may be any of known ones, but preferably the following are preferred. That is, the developer for developing the photosensitive printing plate according to the present invention contains at least one alkali agent and water as essential components.

As the alkaline agent contained as an essential component in the developer, sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium or ammonium salt of secondary or tertiary phosphate, sodium metasilicate, Inorganic alkali agents such as sodium carbonate and ammonia, mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or diisopropylamine, n-
Organic amine compounds such as butylamine, mono-, di- or triethanolamine, mono-, di- or triisopropanolamine, ethyleneimine, and ethylenediimine.

The content of these alkali agents in the developer is 0.05 to
It is 10% by weight, preferably 0.5 to 5% by weight. If the amount is less than 0.05% by weight, the development becomes poor, and if it exceeds 10% by weight, the printing performance as a lithographic printing plate is adversely affected.

The developer for developing the photosensitive printing plate according to the present invention may contain a specific organic solvent, if necessary.

Such an organic solvent is capable of dissolving or swelling the non-exposed portion (non-image portion) of the above-described photosensitive composition layer when contained in a developer, and at the same time, at room temperature (20 ° C.). An organic solvent having a solubility of 10% by weight or less. Any organic solvent may be used as long as it has such properties, and examples thereof include, but are not limited to, the following. That is, for example, carboxylic acid esters such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate, butyl levulinate; ethyl butyl ketone, methyl isobutyl ketone; Ketones such as cyclohexanone; alcohols such as ethylene glycol monobutyl ether, ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenylcarbinol, n-amyl alcohol and methyl amyl alcohol; alkyls such as xylene Substituted aromatic hydrocarbons; methylene dichloride,
Examples include halogenated hydrocarbons such as ethylene dichloride and monochlorobenzene. One or more of these organic solvents may be used. Among these organic solvents, ethylene glycol monophenyl ether and benzyl alcohol are particularly effective. The content of these organic solvents in the developer is generally 0 to 20% by weight, and more preferably 2 to 10% by weight.

Further, the developer for developing the photosensitive printing plate according to the present invention may contain a water-soluble sulfite, if necessary. As such a water-soluble sulfite, an alkali or alkaline earth metal sulfite is preferable, and examples thereof include sodium sulfite, potassium sulfite, lithium sulfite, and magnesium sulfite. The content of these sulfites in the developer composition is 0 to 4% by weight, preferably 0.1 to 4% by weight.
１1% by weight.

Further, instead of the water-soluble sulfite, an alkali-soluble pyrazolone compound, an alkali-soluble thiol compound, or a hydroxy aromatic compound such as methylresorcin may be contained. Of course, these compounds can be used in combination with a water-soluble sulfite.

In addition, a certain solubilizing agent may be included to assist the dissolution of the above-mentioned organic solvent in water. As such a solubilizing agent, in order to realize the predetermined effect of the present invention, it is preferable to use low molecular alcohols and ketones which are more soluble in water than the organic solvent used.

Further, an anionic activator, an amphoteric activator and the like can also be used. Such alcohols and ketones include, for example, methanol, ethanol, propanol, butanol, acetone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methoxybutanol, ethoxybutanol,
It is preferable to use 4-methoxy-4-methylbutanol, N-methylpyrrolidone and the like. As the activator, for example, sodium isopropylnaphthalenesulfonate, sodium n-butylnaphthalenesulfonate, N-
Sodium methyl-N-pentadecylaminoacetate, sodium lauryl sulfate and the like are preferred. Generally, the amount of the solubilizing agent such as alcohol and ketone used is preferably about 30% by weight or less based on the whole developer.

〔The invention's effect〕

The photosensitive composition of the present invention is excellent in solubility in an organic coating solvent when coated on a support and developability, does not cause diazo residue, and does not cause printing stains.

Example 1 A 0.24 mm thick aluminum plate was coated with a nylon brush and 400
The surface was grained using an aqueous suspension of mesh pumicestone, and then thoroughly washed with water. This was etched by immersing it in a 10% aqueous sodium hydroxide solution at 70 ° C. for 60 seconds, washed with running water and neutralized and washed with 20% nitric acid.
No. 67507, the electrochemical surface roughening method, that is, _VA = 12.
Using a sinusoidal alternating waveform current of 7 V and V _C = 9.1 V, the electrolytic surface roughening treatment was performed in a 1% nitric acid aqueous solution at an anode electricity of 160 coulomb / dm ² . Continue to soak in 30% sulfuric acid aqueous solution,
After desmutting at 55 ° C. for 2 minutes, anodizing treatment was performed in a 7% aqueous sulfuric acid solution so that the coating amount of aluminum oxide was 2.0 g / m ² . Then 3% of sodium silicate at 70 ℃
It was immersed in an aqueous solution for 1 minute, washed with water and dried. The following photosensitive solution was applied to the aluminum plate obtained as described above using a wheeler and dried at 80 ° C. for 2 minutes. Dry weight was 2.0 g / m ^2.

 The diazo resins used in the following photosensitive solutions are shown in Table 1.

Next, as a comparative example, a photosensitive solution using the following diazo resin was applied to the above photosensitive solution and dried. Dry weight 2.0 g / m ²
Met.

(Diazo resin used in Comparative Examples 1 and 2) Comparative Example 1 Dioctylnaphthalene sulfonate of 4-diazodiphenylamine-formaldehyde condensate (weight average molecular weight)
1800) Comparative Example 2 n-dodecylbenzenesulfonate of 4-diazo-4'-methyldiphenylamine-benzaldehyde condensate (weight average molecular weight 1900) [Evaluation of printing stain] Each photosensitive lithographic printing obtained in this manner. The plate was image-exposed for 1 minute from a distance of 1m with a PS light manufactured by Fuji Photo Film Co., Ltd., immersed in the following developer for 1 minute at room temperature, and then lightly rubbed with absorbent cotton to remove unexposed areas. Lithographic printing plates (I) to (VII) having bright blue images were obtained.

Each printing plate was printed on high quality paper with a commercially available ink using a KOR printing machine manufactured by Heidelberg.

When the printing stains of the lithographic printing plates (I) to (VII) were examined, they were as shown in Table 1.

As can be seen from Table 1, the lithographic printing plates (I) to (V) using the photosensitive composition of the present invention were obtained by comparing (V) in Comparative Examples 1 and 2.
Compared with (I) and (VII), there is no print stain at the time of printing, and it is very excellent. This indicates that the composition of the present invention has excellent developability and does not cause diazo residue.

Example 2 Each photosensitive lithographic printing plate used in Example 1 was image-exposed for 1 minute from a distance of 1 m with a PS light manufactured by Fuji Photo Film Co., Ltd., and immersed in the following developer at room temperature for 1 minute. Then, the surface was lightly rubbed with absorbent cotton to remove unexposed portions to obtain lithographic printing plates (VIII) to (XIV) having bright blue images.

In the same manner as in Example 1, printing was performed on high quality paper using commercially available inks with a KOR type printing machine manufactured by Heidelberg Co. using each printing plate.

The printing stains of the lithographic printing plates (VIII) to (XIV) were examined, and the results were as shown in Table 2.

As can be seen from Table 2, the lithographic printing plates (VIII) to (XII) using the photosensitive composition of the present invention were the same as those of Comparative Example (XII).
Compared with (I) and (XIV), there is no print stain at the time of printing, and it is very excellent. This indicates that the composition of the present invention is excellent in developability and does not cause diazo residue.

Claims (1)

(57) [Claims] 1. A photosensitive composition containing a diazo resin and a polymer compound soluble in an organic solvent, wherein the diazo resin is a condensate of an aromatic diazonium compound and an aldehyde having a sulfonic acid group or an equivalent thereof. A photosensitive composition, comprising: