JPH0549698B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a photosensitive polyester resin that can be suitably used for photosensitive lithographic printing plates, and more specifically, it has excellent photosensitivity, printing durability, and oil sensitivity, and can be developed with an aqueous developer. The present invention relates to a method for producing a photosensitive polyester resin.

[Formula] Skeleton (hereinafter referred to as cinnamic acid skeleton) performs a unique photoduplexing reaction, so various photosensitive resins with a cinnamic acid skeleton introduced into the side chain or main chain of the molecule have been studied. It is. Examples include polyvinyl alcohol, polyepichlorohydrin, polystyrene, acrylic resins, epoxy resins, and polyesters and polyamides having a cinnamic acid skeleton in the main chain, some of which have been put into practical use. For example, there are polyvinyl cinnamic esters produced by the reaction of polyvinyl alcohol and cinnamic acid chloride, and polyesters produced by the condensation of diethyl phenylene diacrylate and 1,4-di-β-hydroxyethoxycyclohexane. , these are used as image forming materials for printing plates, LSI devices, etc. Among the photodimerizable photosensitive resins mentioned above, photosensitive polyester resins having a cinnamic acid skeleton in the molecular main chain produced by condensation of phenylene diacrylic acid or its alkyl ester with glycol are relatively expensive. It is said to have photosensitivity. However, since these photosensitive resins exhibit solubility only in organic solvents, organic solvents are used as developing solutions when developing photosensitive layers made from these resins. When using an organic solvent as a developer, there are many problems in terms of development workability, safety and hygiene of the working environment, economic efficiency, and prevention of pollution such as air pollution.Therefore, photosensitive resins that can be developed with an aqueous developer development is desired. In recent years, photosensitive resins having a cinnamoyloxy group in the main chain and a sulfo group adjacent to the aromatic nucleus have been proposed as such resins (Japanese Unexamined Patent Publication No. 130897/1989). These resins are still insufficient in terms of photosensitivity, developability, etc., and in terms of printing durability and oil sensitivity when used as photosensitive materials for printing plates, and improvements are desired. Therefore, an object of the present invention is to provide a method for producing a photosensitive resin that can be developed with an aqueous developer. Another object of the present invention is to provide a method for producing a photosensitive resin that has sufficient printing durability and oil sensitivity when used as a photosensitive material for a printing plate. The present inventors have developed a method for achieving such an objective by using (1) (a) a dicarboxylic acid having a photosensitive unsaturated double bond adjacent to an aromatic nucleus and (b) the general formula -SO ₃ M
(In the formula, M represents a monovalent alkali metal atom)
A polyhydric carboxylic acid component containing a dicarboxylic acid or a derivative thereof having a group represented by (2) a polyhydric alcohol component containing a glycol having a bisphenol skeleton and/or a tricyclodecane skeleton is reacted. A method for producing a photosensitive polyester resin is provided. Examples of the photosensitive unsaturated dicarboxylic acids used in the present invention include dicarboxylic acids represented by the following general formulas (1) to (7), and examples of derivatives of these dicarboxylic acids include dimethyl esters of these dicarboxylic acids. , dialkyl esters such as diethyl ester, di(ethylene glycol) esters such as di(ethylene glycol) esters, di(propylene glycol) esters, and the like. (In the above general formulas (1) to (7), R ₁ and R' ₁ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a carbon number 1
~4 alkoxyl group, halogen atom, or nitro group, _R2 represents an alkylene group having 2 to 4 carbon atoms, l represents an integer of 1 to 5, and n represents 1 to 4.
represents an integer of 4, and m represents an integer of 1 to 5. ) Preferred examples of the dicarboxylic acids or derivatives thereof include p-phenylene diacrylic acid, m-phenylene diacrylic acid, 2,5-dimethoxy-p-phenylene diacrylic acid, and 2-nitro-p-phenylene diacrylic acid. Diacrylic acid, p-carboxycinnamic acid, cinnamylidenemalonic acid, bis(p-cinnamic acid) diethylene glycol ether, bis(p-carboxybenzal)cyclohexanone, bis(p-carboxybenzal)cyclopentanone, P, Mention may be made of dicarboxylic acids such as P'-chalcone dicarboxylic acid or their diesters as mentioned above. In addition, examples of dicarboxylic acids and derivatives thereof having a -SO ₃ M group include 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, 3-sodium sulfophthalic acid, 3-potassium sulfophthalic acid, and 4-sodium sulfophthalic acid. Phthalic acid, 4-potassium sulfophthalic acid, α-sodium sulfosuccinic acid, α-potassium sulfosuccinic acid, β-sodium sulfoadipic acid, 2,5-
Disodium sulfoadipic acid, 5-(γ-sodium sulfopropoxy)isophthalic acid, 5-
(γ-potassium sulfopropoxy)isophthalic acid,
5-(p-sodium sulfophenoxy)isophthalic acid, 5-(p-potassium sulfophenoxy)
Dicarboxylic acids such as isophthalic acid; dialkyl esters such as dimethyl ester and diethyl ester of the dicarboxylic acids; di(alkylene glycol) esters such as di(ethylene glycol) ester and di(propylene glycol) ester of the dicarboxylic acids; be able to. The preferred amount of the dicarboxylic acid having a -SO ₃ M group or its derivative is 5 to 70 mol % of the total polyhydric carboxylic acid component. As the content of the -SO ₃ M group increases, the developability of the resin with an aqueous developer increases, but the oil sensitivity (ink receptivity) of the resin decreases. Within the above preferred range, both developability and oil sensitivity can be improved. As the polycarboxylic acid component, other polycarboxylic acids or derivatives thereof can be used in combination with the photosensitive unsaturated dicarboxylic acids, dicarboxylic acids having a -SO ₃ M group, or derivatives thereof. Examples of compounds include succinic acid, adipic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, tetrabromophthalic acid, tetrachlorophthalic acid, maleic acid, fumaric acid, Examples include polyhydric carboxylic acids such as itaconic acid, hymic acid, carboxynorbornane acetic acid, trimellitic acid, and pyromellitic acid, or their anhydrides or ester derivatives thereof. However, the use of large amounts of these other polyhydric carboxylic acids or their derivatives should be avoided because it causes a decrease in the photosensitivity of the resin.In order to obtain sufficiently high photosensitivity, it is necessary to It is desirable that the amount of the derivative used be 30 to 95 mol% of the total polyhydric carboxylic acid component. Examples of glycols having a bisphenol skeleton used in the present invention include glycols represented by the following general formula (8), and examples of glycols having a tricyclodecane skeleton include glycols represented by the following general formula (9). be able to. (In formulas (8) and (9) above, R ₂ and R ₃ each represent an alkylene group having 2 to 4 carbon atoms, and R ₄ and
R ₅ each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, k and l each represent an integer of 1 or more, and m and n each represent an integer of 0 or 1 or more. However, k+l is an integer of 2 to 20, and m+n is an integer of 0 or 1 to 20. ) These glycols include, for example, ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, ethylene oxide adducts of bisphenol F, propylene oxide adducts of bisphenol F, tricyclodecane dimethanol, Examples include an ethylene oxide adduct of tricyclodecane dimethanol and a propylene oxide adduct of tricyclodecane dimethanol. As the polyhydric alcohol component, other polyhydric alcohols can be used together with the above-mentioned glycols. Examples of such polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol,
Dipropylene glycol, polyethylene glycol, polypropylene glycol, neopentyl glycol, 1,3-butylene glycol, 1,6
-hexanediol, 2,2,4-trimethylpentane-1,3-diol, 2-butene-1,4
- diol, cyclohexane-1,4-diol, cyclohexanedimethanol, 1,4-bis-β-hydroxyethoxycyclohexane, hydrogenated bisphenol A, hydrogenated bisphenol F, ethylene oxide adduct of hydrogenated bisphenol A,
Propylene oxide adduct of hydrogenated bisphenol A, ethylene oxide adduct of hydrogenated bisphenol F, propylene oxide adduct of hydrogenated bisphenol F, 3-methylpentane-1,3,
Examples include 5-triol, trimethylolpropane, trimethylolethane, pentaerythritol, glycerin, dipentaerythritol, diglycerin, and sorbitol. The preferred content of the bisphenol skeleton and/or tricyclodecane skeleton is per 1000 g of the weight of the resin.
The content is 0.25 to 3.0 mol, and a particularly suitable content is 0.4 to 3.0 mol.
It is 2.5 moles. When a photosensitive polyester resin within this range is used as a photosensitive material for a lithographic printing plate, sufficient printing durability and oil sensitivity can be obtained. Such photosensitive polyester resins can be prepared by means known in the field of ordinary polyester synthesis, such as "Lecture on Polymerization Reactions 9, Polycondensation" published by Seisho.
Written by Ogata, published by Kagaku Dojinsha, or US patented
It can be easily produced by the method described in Japanese Patent No. 3622320. That is, after the dicarboxylic acid component and the glycol component are reacted (esterification reaction or transesterification) in the presence of a catalyst and an inhibitor that are added as necessary, the pressure inside the reactor is gradually reduced to remove excess It can be produced by distilling glycol. The reaction temperature is 150 to 250
℃ is preferable, and the reduced pressure is preferably 3 mmHg or less. Examples of catalysts used in producing photosensitive polyester resins include organometallic compounds such as tetraisopropyl titanate, tetrabutoxytitanate, dibutyltin oxide, dibutyltin laurate, lithium ethoxide, zinc acetate, manganese acetate, and calcium acetate. ;titanium dioxide,
Inorganic metal compounds such as antimony trioxide, calcium oxide, zinc chloride, etc. can be used. The amount used is
The metal component is preferably 50 to 10,000 ppm. Inhibitors are used to minimize crosslinking and branching of ethylenically unsaturated groups that tend to occur during polycondensation reactions, and include, for example, phenothiazine, hydroquinone, hydroquinone monomethyl ether, 2,6-di- Tert-butyl-p-cresol, p-benzoquinone, etc. can be used. The amount used is preferably 50 to 2000 ppm. The photosensitive polyester resin obtained by the present invention preferably has an intrinsic viscosity of 0.12 or more,
A value of 0.20 to 0.70 is more preferable. The above-mentioned intrinsic viscosity is a value measured at 25°C using a phenol-monochlorobenzene mixed solvent (1:1 volume) as the solvent. A photosensitive polyester resin having such a viscosity has sufficient photosensitivity and good printing durability when used as a photosensitive material for a printing plate. The photosensitive polyester resin according to the present invention is usually prepared as a composition in a suitable solvent or, if necessary, with additives such as sensitizers, pigments, dyes, fillers, stabilizers, crosslinking agents, and plasticizers. It is used as a composition with added. Suitable solvents vary depending on the composition and molecular weight of the resin, but generally include chlorinated solvents such as methylene chloride, chloroform, trichloroethane, trichloroethylene, monochlorobenzene, dichlorobenzene, and carbon tetrachloride; tetrahydrofurfuryl alcohol, diacetone alcohol,
Alcohol solvents such as methyl lactate, ethyl lactate, and benzyl alcohol; Ether solvents such as tetrahydrofuran and dioxane; Glycol monoalkyl ether solvents such as glycol monomethyl ether and glycol monoethyl ether; Glycol methyl ether acetate, glycol ethyl ether acetate, Ester solvents such as ethyl acetate; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-methyl-4-methoxy-2-pentanone; dimethylformamide, dimethylacetamide, N-
Nitrogen-containing compounds such as methylpyrrolidone and nitrobenzene; dimethyl sulfoxide and the like can be used, and these solvents can be used alone or in combination of two or more. As the sensitizer, any one commonly used in this field can be used, such as benzophenone derivatives, benzanthrone derivatives, quinones,
Aromatic nitro compounds, naphthothiazoline derivatives,
benzothiazoline derivatives, ketocoumarin compounds,
Alternatively, pyrylium salts, thiapyrylium salts, etc. can be used. Examples of such sensitizers include Michler's ketone, diethylaminoethylbenzophenone, benzanthrone, 6,11-dichlorobenzanthrone, (3-methyl-1,3-diaza-1,9-benz)anthropic. Lamido,
1,8-dimethoxyanthraquinone, 1,2-benzanthraquinone, 5-nitroacenaphthene,
2-nitrofluorene, 2,7-dinitrofluorene, 1-nitronaphthalene, 1,5-dinitronaphthalene, 9-nitrodiphenyl, 2-dibenzoylmethylene-3-methylnaphthothiazoline,
2-benzoylmethylene-1-methylnaphthothiazoline, 2-bisfuroyrmethylene-3-methylbenzothiazoline, 2-benzoylmethylene-3
-Methylbenzothiazoline, 3,3-carbonyl-bis(7-diethylaminocoumarin), 2,4,
6-triphenylthiapyrylium perchlorate, 2,6-bis(p-ethoxyphenyl)-4
-(pn-amyloxyphenyl)thiapyrylium perchlorate, 2,4,6-triphenylthiapyrylium tetrafluoroborate, and the like. In addition, when the photosensitive polyester resin according to the present invention is used as a photosensitive material for a lithographic printing plate, acrylic resin, polyvinyl acetal resin, esterified cellulose, epoxy resin, polyurethane, etc. are also used as additives to improve oil sensitivity. can. The photosensitive composition containing the photosensitive polyester resin of the present invention is formulated to have an appropriate viscosity so that it can be applied to commonly used coating techniques such as whirler coating, dip coating, curtain coating, roll coating, and spray coating. , air knife coating, doctor knife coating, spinner coating, and other known coating methods. Specific examples of materials to be coated include aluminum plates, zinc plates, copper plates, stainless steel plates, and other metal plates; sheets and plates of synthetic resins such as polyethylene terephthalate, polycarbonate, and cellulose derivatives; and melt-coated synthetic resins. Alternatively, examples include paper coated with a synthetic resin solution, and composite materials in which a metal layer is provided on a synthetic resin by vacuum deposition, lamination, or other techniques. After coating, the coating solution is dried and solidified by a well-known method to obtain a printing original plate having a photosensitive layer provided on the support. The photosensitive layer of this printing original plate is subjected to imagewise exposure using a negative image to harden and insolubilize the exposed areas of the photosensitive layer, and then developed with an aqueous developer to dissolve and remove the unexposed areas. images can be formed. In this case, as the aqueous developer, a developer containing water as a main component and optionally further additives such as an alcoholic solvent, a surfactant, and a PH adjuster can be used. Suitable light sources used for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, lasers, and the like. As mentioned above, the photosensitive resin of the present invention is extremely effective for forming a photosensitive layer of a printing plate, but
The use of the composition of the present invention is not necessarily limited to the photosensitive layer of a printing plate, but can also be used, for example, as a photoresist for various types of microfabrication. EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded. Examples 1 to 11, Comparative Examples 1 to 2 (1) Production of photosensitive polyester resin Each mixture having the composition listed in Table 2 was stirred with a catalyst (5 g of dibutyltin oxide) and an inhibitor (0.5 g of phenothiazine). The mixture was charged into a reactor equipped with an apparatus, a nitrogen gas inlet tube, a thermometer, and a distillation tube, and the reaction was started by heating to 180° C. (210° C. for Example 6) while stirring in a nitrogen gas atmosphere. After that, heating and stirring were continued for 3 hours, and after the alcohol produced by the reaction stopped distilling out, the pressure inside the reactor was gradually reduced to 1 mmHg at the same temperature. Thereafter, heating and stirring were continued for 4 hours under the same reduced pressure, and after the distillate had stopped coming out, the pressure inside the reactor was returned to normal pressure with nitrogen gas, and the produced resin was taken out. (2) Measurement of photosensitivity of photosensitive polyester resin Add methyl cellosolve to the photosensitive polyester resin in (1) above to prepare a 4% solution by weight, and add 5-nitroacenaphthene (10% by weight based on the resin) to this solution. %) to prepare a photosensitive composition. This photosensitive composition was coated with a whirler on an aluminum plate whose surface had been grained and anodized, and this was dried to prepare a photosensitive plate. A step wedge with a height difference of 0.15 was brought into close contact with the thus obtained photosensitive plate, and a metal halide lamp with an output of 1 kW ("Idle Fin 1000" manufactured by Iwasaki Electric Co., Ltd.) was installed 1 m away from the step wedge to perform the above steps. The photosensitive plate was exposed for 1 minute. Thereafter, this photosensitive plate was developed with a developer (a) or (b) having the composition shown in Table 1 below, and a developing ink was applied. The highest number of insolubilized steps was defined as the photosensitivity.

[Table] Surfactant
(3) Evaluation of printing durability and oil sensitivity (ink receptivity) when photosensitive polyester resin is used as a photosensitive material for printing plates. Closely attach the negative film, and from now on 1
A metal halide lamp with an output of 1 kW (Idol Fin manufactured by Iwasaki Electric Co., Ltd.) was installed at a distance of
1000'') for an exposure time giving a photosensitivity of 6, and then developed with the developer shown in Table 1 (a) or (b) to produce a printing plate. The printing plate produced in this way was attached to a four-color lithographic printing machine, and printed using standard ink for lithographic printing under conditions similar to actual lithographic printing. and liposensitivity was evaluated. Printing durability is determined by thickening of halftone dots,
The evaluation is based on whether a print faithful to the original image can be obtained without plate skipping, etc., and the oil sensitivity is evaluated by whether a clear image can be obtained without blurring or poor ink adhesion on the print. It was also evaluated. The contents and results of each of the above examples are summarized in Table 2.

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Claims (1)

[Scope of Claims] 1 (1) (a) A dicarboxylic acid having a photosensitive unsaturated double bond adjacent to an aromatic nucleus, and (b) a dicarboxylic acid having the general formula -SO ₃ M (where M is a monovalent alkali); (2) a polyhydric carboxylic acid component containing a dicarboxylic acid or a derivative thereof having a group represented by (representing a metal atom); and (2) a polyhydric alcohol component containing a glycol having a bisphenol skeleton and/or a tricyclodecane skeleton. A method for producing a photosensitive polyester resin, which comprises reacting the resin. 2 A dicarboxylic acid or its derivative having a photosensitive unsaturated double bond adjacent to an aromatic nucleus has the following general formula:
The method according to claim 1, which is a dicarboxylic acid represented by (1) to (7) or a derivative thereof. (In the above general formulas (1) to (7), R ₁ and R ₁ ' are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a carbon number 1
~4 alkoxyl group, halogen atom, or nitro group, _R2 represents an alkylene group having 2 to 4 carbon atoms, l represents an integer of 1 to 5, and n represents 1 to 4.
represents an integer of 4, and m represents an integer of 1 to 5. ) 3. Claims 1 or 2 in which the amount of the dicarboxylic acid or derivative thereof having a photosensitive unsaturated double bond adjacent to an aromatic nucleus is 30 to 95 mol% of the entire polyhydric carboxylic acid component. Method described. 4 The amount of dicarboxylic acid having a group represented by the general formula -SO ₃ M (wherein M represents a monovalent alkali metal atom) or its derivative used is 5 to 70 moles based on the total polyhydric carboxylic acid component. %, the method according to claims 1 to 3. 5 A glycol having a bisphenol skeleton is
5. The method according to claims 1 to 4, wherein the glycol is represented by the following general formula (8), and the glycol having a tricyclodecane skeleton is a glycol represented by the following general formula (9). (In formulas (8) and (9) above, R ₂ and R ₃ each represent an alkylene group having 2 to 4 carbon atoms, and R ₄ and
R ₅ each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, k and l each represent an integer of 1 or more, and m and n each represent 0 or 1.
represents an integer greater than or equal to However, k+l is an integer of 2 to 20, and m+n is an integer of 0 or 1 to 20. ) 6. The method according to claims 1 to 5, wherein the content of bisphenol skeleton and/or tricyclodecane skeleton in the photosensitive polyester resin is 0.3 to 3.0 mol per 1000 g of the resin.