JP2900137B2 - Photocurable resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a photocurable resin. More specifically, the present invention is useful as a photosensitive resin for a photoresist ink for copper etching when manufacturing a printed wiring board, or a solder photoresist as a permanent protective film, and has good photocurability, The present invention relates to a photo-curable resin which gives a cured product having excellent diluted alkali developability and excellent adhesion.

[0002]

2. Description of the Related Art At present, as a resist film for copper etching when manufacturing a printed wiring board, a photocurable resin composition, that is, a photoresist is formed by sandwiching a transparent film called a carrier film and a cover film. "Dry film" with sandwiched form
What is said to be used mainly. This dry film is peeled off the cover film on one side, laminated on the substrate, applied with a photomask, cured by ultraviolet rays, and then peeled off the carrier film on the surface,
It is developed with a dilute aqueous alkaline solution. Due to the ease of handling of dry film, continuous process
Although automation is possible, it is basically difficult to improve the adhesion and followability of the dry film coating to roughness, scratches, and irregularities on the copper surface because the dry film is soft but solid. In addition, due to the form of the dry film, it is inevitable that the thickness of the dry film becomes a certain level or more. Since the UV exposure is performed by applying a photomask with the carrier film attached to the surface, the resolution of the resist pattern is naturally limited. In order to avoid the above-mentioned drawbacks of the dry film, a method of printing a liquid resist ink on a whole surface with a screen or a roll, drying, and then performing UV exposure and development to form a resist film is also used. The photocurable resin used in the liquid resist ink is a resin obtained by reacting an epoxy acrylate resin with a dibasic acid (Japanese Patent Publication No. 1-54390), or a styrene-maleic anhydride copolymer resin containing a hydroxyl group. A resin obtained by reacting a radical polymerizable monomer (JP-A-63-205649) is mainly used. However, such an ultraviolet curable resin based on an epoxy resin and a styrene-maleic anhydride copolymer resin has a small amount of radically polymerizable unsaturated groups to be introduced, and has a lower photocurability than a dry film. There is a disadvantage that it is bad. In addition, if the amount of the radical polymerizable monomer in the composition is increased in order to improve the photocurability, the dried coating film becomes softer and the surface adhesion is developed. Curability improvement was not possible.

[0003]

SUMMARY OF THE INVENTION The present invention is to provide a photocurable resin which has good photocurability, is easy to be developed with a dilute alkali, and is excellent in developing solution resistance and etching solution resistance. It was made for the purpose of.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a resin having a radical polymerizable unsaturated group and a carboxyl group has one epoxy group and one carboxyl group. When a resin obtained by reacting a compound having two or more radically polymerizable unsaturated groups is used as a liquid resist ink, it is cured with a small amount of light, has excellent dilute alkali developability, and has good adhesion. And completed the present invention on the basis of this finding. That is, the present invention relates to (1) reacting a radical polymerizable unsaturated monocarboxylic acid with an epoxy resin and further reacting a dibasic acid anhydride to form a radical polymerizable unsaturated acyl group and a carboxyl group. To the carboxyl group of the resin
A photocurable resin obtained by reacting one epoxy group with a compound having one or more radically polymerizable unsaturated groups, (2)
(1) The resin having a radical polymerizable unsaturated acyl group and a carboxyl group has an acid value of 80 to 170 mgKOH / g.
(3) A compound having one epoxy group and one or more radically polymerizable unsaturated groups per mole of carboxyl group of the resin having a radically polymerizable unsaturated acyl group and a carboxyl group. (1) The photocurable resin according to (1) or (2), which is obtained by reacting 0.1 to 0.5 mol, and (4) a photocurable resin having an acid value of 40 to 110 mgKOH / g.
(1) A photocurable resin according to (3). Further, as a preferred embodiment of the present invention, (5) the epoxy resin is a bisphenol A type epoxy resin, a phenol novolak type epoxy resin, an o-cresol novolak type epoxy resin, or a bisphenol A novolak type epoxy resin. 4) The photocurable resin according to the item,
(6) The epoxy resin having a softening point of 60 to 100 ° C.
The photocurable resin described in (1) to (5), and (7) a radical polymerizable unsaturated monocarboxylic acid reacting in an amount of from 0.9 to 1.1 mol per mol of an epoxy group contained in the epoxy resin. ) ~
(6) The photocurable resin according to the item (8), (8) a dibasic acid anhydride is used in an amount of 0.4 to 1 per mole of hydroxyl group contained in a product obtained by reacting a radical polymerizable unsaturated monocarboxylic acid with an epoxy resin. (1)
(9) reacting a dibasic acid anhydride at 60 to 120 ° C. with a product obtained by reacting a radical polymerizable unsaturated monocarboxylic acid with an epoxy resin; (1) to the photocurable resin according to (8), and
(10) A compound having one epoxy group and one or more radically polymerizable unsaturated groups is reacted with a resin having a radically polymerizable unsaturated acyl group and a carboxyl group at 80 to 120 ° C. (9) The photocurable resin according to the item,
Can be mentioned.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxy resin used in the present invention is not particularly limited. Examples thereof include bisphenol A epoxy resin, bromide-containing epoxy resin, bisphenol F epoxy resin, bisphenol AD epoxy resin, phenol novolak epoxy resin. Resin, o-cresol novolak epoxy resin, bisphenol A novolak epoxy resin, cycloaliphatic epoxy resin, glycidyl ester resin, glycidylamine resin, heterocyclic epoxy resin, and the like can be given. Among these, bisphenol A type epoxy resin, phenol novolak type epoxy resin, o-cresol novolak type epoxy resin and bisphenol A novolak type epoxy resin can be particularly preferably used. The bisphenol A type epoxy resin can be obtained by reacting bisphenol A with epichlorohydrin.
Phenol novolak type epoxy resin, o-cresol novolak type epoxy resin and bisphenol A novolak type epoxy resin are reaction products of phenol, o-cresol or bisphenol A with formaldehyde, and are phenol novolak, o-cresol novolak or bisphenol A. It can be obtained by reacting novolak with epichlorohydrin. In the present invention, the bisphenol A type epoxy resin preferably has a softening point of 60 to 80 ° C, and the novolak type epoxy resin preferably has a softening point of 70 to 95 ° C. In the present invention, one type of these epoxy resins can be used alone, and two or more types can be used in combination.

In the present invention, an epoxy resin is reacted with a radically polymerizable unsaturated monocarboxylic acid. The oxirane ring is cleaved by the reaction between the epoxy group and the carboxyl group to form a hydroxyl group and an ester bond. The radically polymerizable unsaturated monocarboxylic acid used is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, vinyl acetic acid, sorbic acid, and cinnamic acid. Among these, acrylic acid can be used particularly preferably because it has good reactivity with epoxy groups and the resulting resin has excellent photocuring properties. There is no particular limitation on the reaction method between the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid.For example, the reaction may be performed by heating the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid in a suitable diluent. it can. As the diluent, for example, methyl ethyl ketone, ketones such as cyclohexanone, toluene, aromatic hydrocarbons such as xylene, methanol, isopropanol, alcohols such as cyclohexanol, cyclohexane, alicyclic hydrocarbons such as methylcyclohexane, Petroleum solvents such as petroleum oil, petroleum naphtha, etc.
Cellosolves such as cellosolve and butyl cellosolve, carbitols such as carbitol and butyl carbitol, ethyl acetate, butyl acetate, cellosolve acetate;
Acetates such as butyl cellosolve acetate, carbitol acetate, and butyl carbitol acetate can be exemplified. In the present invention, it is preferable to react 0.9 to 1.1 moles of the radical polymerizable unsaturated monocarboxylic acid per 1 mole of the epoxy group of the epoxy resin. If the epoxy group is excessive, an undesired reaction may be caused during the subsequent synthesis reaction, resulting in gelation of the resin or a decrease in storage stability. In addition, when the radically polymerizable unsaturated monocarboxylic acid is excessive, unreacted carboxyl groups remain, and a low-molecular-weight product is contained in the resin, and the properties of the cured product may be reduced. is there. The reaction temperature between the epoxy resin and the radical polymerizable unsaturated monocarboxylic acid is 10
The temperature is preferably from 0 to 120 ° C. Reaction temperature 120
If the temperature exceeds ℃, the radically polymerizable unsaturated monocarboxylic acid may cause thermal polymerization and gel during the reaction. In the reaction of the epoxy resin and the radical polymerizable unsaturated monocarboxylic acid in a diluent, the amount of the diluent is preferably 20 to 50% by weight based on the total weight of the reaction system. The reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid can be subjected to the next reaction with a dibasic acid anhydride without isolation, as a solution of a diluent.

In the present invention, a dibasic acid anhydride is reacted with a reaction product of an epoxy resin and a radically polymerizable unsaturated monocarboxylic acid. The dibasic acid anhydride to be reacted is not particularly limited, and any of a saturated dibasic acid anhydride and an unsaturated dibasic acid anhydride can be used. Examples of such dibasic acid anhydrides include, for example, succinic anhydride, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride,
Examples include endomethylenetetrahydrophthalic anhydride, methylendmethylenetetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride, and chlorendic anhydride. Among them, succinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride and methyltetrahydrophthalic anhydride can be particularly preferably used. One of these dibasic acid anhydrides can be used alone, or two or more can be used in combination. In the present invention, the dibasic acid anhydride reacts with the hydroxyl group of the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid to generate an ester bond and a free carboxyl group. The hydroxyl group of the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid has, in addition to the hydroxyl group generated by the reaction of the epoxy group and the radically polymerizable unsaturated monocarboxylic acid, the epoxy resin originally has. Hydroxyl groups. The amount of the dibasic acid anhydride to be reacted is 0.4 per mole of the hydroxyl group of the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid.
Preferably it is ~ 1.0 mol. When the amount of the dibasic acid anhydride to be reacted is less than 0.4 mol per 1 mol of the hydroxyl group of the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid, the dilute alkali phenomenon may decrease. is there. When the amount of the dibasic acid anhydride to be reacted exceeds 1.0 mol per 1 mol of the hydroxyl group of the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid, unreacted dibasic acid anhydride remains. However, it may adversely affect the subsequent reaction process. In the present invention, a dibasic acid anhydride is added to a reaction product of an epoxy resin and a radically polymerizable unsaturated monocarboxylic acid to react. When the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid is present as a diluent solution,
By adding a dibasic acid anhydride to this solution, dissolving it by heating and reacting, the reaction can be favorably advanced. The reaction temperature is preferably from 60 to 120 ° C,
It is more preferable that the temperature is 100C. In the present invention, the product obtained by reacting a reaction product of an epoxy resin and a radically polymerizable unsaturated monocarboxylic acid with a dibasic acid anhydride preferably has an acid value of 80 to 170 mgKOH / g. The acid value of the product obtained by adding the dibasic acid anhydride can be easily adjusted by appropriately selecting the amount of the dibasic acid anhydride to be reacted.

In the present invention, a resin having a radical polymerizable unsaturated acyl group and a carboxyl group, which is obtained by reacting a radical polymerizable unsaturated monocarboxylic acid with an epoxy resin and further reacting a dibasic acid anhydride. Is reacted with a compound having one epoxy group and one or more radically polymerizable unsaturated groups. The epoxy group of a compound having one epoxy group and one or more radically polymerizable unsaturated groups and the carboxyl group of a resin having a radically polymerizable unsaturated acyl group and a carboxyl group react to form an ester bond. The radical polymerizable unsaturated group is bonded to obtain the photocurable resin of the present invention. In the photocurable resin of the present invention, since the radical polymerizable unsaturated group introduced by the last reaction is bonded to the outermost part of the main chain of the photocurable resin, the reactivity in the polymerization reaction of the resin by light is reduced. It is stereochemically high and has excellent photocurability. In the present invention, examples of the compound having one epoxy group and one or more radically polymerizable unsaturated groups include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, and a compound represented by the general formula [1]. Can be mentioned.

Embedded image However, in the general formula [1], n is 0, 1 or 2, R is hydrogen or a methyl group, A is a 6-oxabicyclo [3.1.0] hexyl group, 7-oxabicyclo [4 .1.0] heptyl group or 8-oxabicyclo [5.1.0] octyl group. In the present invention, a compound having one epoxy group and one or more radically polymerizable unsaturated groups is added to and reacted with a resin having a radically polymerizable unsaturated acyl group and a carboxyl group. When a resin having a radical polymerizable unsaturated acyl group and a carboxyl group is present as a solution of a diluent, a compound having one epoxy group and one or more radical polymerizable unsaturated groups is added to the solution and dissolved. By doing so, the reaction can be favorably advanced. In addition, a diluent can be further added in order to suitably perform stirring during the reaction. The reaction temperature is preferably from 80 to 120 ° C, and from 100 to 1
More preferably, the temperature is 20 ° C. The photocurable resin of the present invention thus obtained has an acid value of 40 to 110 mg KO.
H / g is preferred. The photocurable resin of the present invention can be suitably used as a composition for a photoresist ink for etching by mixing with a photopolymerization initiator and a diluent. In the composition for etching photoresist ink, if necessary, known fillers such as barium sulfate and silicon oxide, known color pigments such as phthalocyanine green, phthalocyanine blue, titanium dioxide, and carbon black, defoamers, and leveling Various additives such as agents, monohydroxyethyl phthalate (meth) acrylate, monohydroxyethyl succinate (meth) acrylate, known dilute alkali-soluble diluted acrylic monomers such as acrylic acid dimer, or hydroquinone, hydroquinone monomethyl ether, Pyrogallol, t-
A known polymerization inhibitor such as butyl catechol can be blended.

[0009]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. Photocurability, developability and coating film performance were evaluated by the following methods. (1) Photocurable A 21-step tablet is applied to the test copper foil substrate,
UV exposure was performed at irradiation doses of 100 mJ / cm ² and 300 mJ / cm ² , respectively, and after the completion of alkali development, evaluation was performed in the largest step in which the coating film completely remained. The larger the step, the better the photocurability. (2) Dilute alkali developability Developability when a test copper foil substrate subjected to UV exposure was developed with a 1% by weight aqueous sodium carbonate solution as a developer after being cured by UV exposure, and stirred at 20 ° C. for 5 minutes with a stirrer. Was evaluated according to the following criteria. ◎: Developable in less than 1 minute ○: Developable in more than 3 minutes and less than 3 minutes △: Developable in more than 3 minutes and less than 5 minutes ×: Developable in less than 5 minutes (3) Developer resistance After the dilute alkali developability test, the resist coating surface of the test printed circuit board immersed in a 1% by weight aqueous solution of sodium carbonate at 30 ° C. for 1 minute was observed and evaluated according to the following criteria. ◎: The coating film was not peeled at all. ○: Less than 10% of the whole was peeled. Δ: 10 to 30% of the whole was peeled. ×: 31% or more of the whole was peeled. Resistance of the resist coating film when the test copper foil substrate on which the pattern of the resist coating film was formed by alkali development was copper-etched by stirring with a stirrer at 20 ° C. for 30 minutes using a 40 ° Be aqueous ferric chloride solution as an etching solution. Was evaluated according to the following criteria. ◎: The coating film was not peeled at all. ：: Less than 10% of the whole was peeled. Δ: 10 to 30% of the whole was peeled. X: 31% or more of the whole was peeled. Example 1 2-liter separable A flask was charged with 414.5 g of ethyl carbitol acetate, 471 g of a bisphenol A type epoxy resin having an epoxy equivalent of 471, a molecular weight of 900, and a softening point of 64 ° C., and 72 g (1 mol) of acrylic acid. Heat to 120 ° C with stirring, 12
The reaction was continued for 10 hours while maintaining 0 ° C. Once the reaction product was cooled to room temperature, 90 g of succinic anhydride (0.9
Mol) and 136.8 g of tetrahydrophthalic anhydride
(0.9 mol), and the mixture was heated to 80 ° C. and reacted for 4 hours. Once again, the reaction product was cooled to room temperature. The acid value of this product solid was 131 mg KOH / g.
To this solution was added 85.2 g of glycidyl methacrylate (0.6 g).
Mol) and 45.8 g of ethyl carbitol acetate
Was added and heated to 110 ° C. with stirring, and the reaction was continued for 6 hours while maintaining 110 ° C. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution was 65% by weight, and the acid value of the resin solid content was 79%.
mgKOH / g. This solution is referred to as a resin solution A-1. 20 g of the resin solution A-1, 2 g of dipentaerythritol tetraacrylate as a photoreactive polyfunctional acrylate, 1 g of a photopolymerization initiator [Ciba-Geigy, Irgacure 907], a photosensitizer [Nippon Kayaku Co., Ltd. 0.25 g of Kayacure DETX-S], 10 g of silica, 0.5 g of phthalocyanine green pigment, and 0.25 g of an antifoaming agent [Nichika Chemical Co., Ltd., Formrex SOL-30] are kneaded with a roll mill (three rolls). An etching photoresist ink composition was prepared. This composition is then
4 sheets each on a copper foil substrate by screen printing 15
It was applied over the entire surface with a film thickness of ２０20 μm. After this was temporarily dried at 75 ° C. for 30 minutes in a hot-air circulation type drying furnace, two of them were put on a photomask for pattern formation, and UV irradiation amounts were 100 mJ / cm ² and 300 mJ by a 3 kW metal halide lamp.
Irradiation was performed one by one at / cm ² , and photo-curing was performed. The other two were applied with a 21-step tablet for light sensitivity evaluation, and the UV irradiation amount was 1 with a 3 kW metal halide lamp.
Irradiation was performed one by one at 00 mJ / cm ² and 300 mJ / cm ² , respectively, and photo-curing was performed. Next, an uncured portion of the coating film was removed using a 1% by weight aqueous solution of sodium carbonate as a developing solution. The two copper foil substrates on which the pattern was formed are then
It was immersed in a 1% by weight aqueous solution of sodium carbonate (30 ° C.) to evaluate the developer resistance. Finally, the copper foil substrate on which the pattern was formed was immersed in a 40 ° Be aqueous solution of ferric chloride to evaluate the etchant resistance. In the course of the copper foil substrate processing step, the photocurability, the dilute alkali developability, the developer resistance and the etchant resistance were evaluated. Photocurable, in the case of UV irradiation dose 100 mJ / cm ² Step 1
0 and Step 12 was performed when the UV irradiation amount was 300 mJ / cm ² . Dilute alkali developability was possible within one minute. In the developer resistance and etchant resistance tests, U
The coating film did not peel at all regardless of the V irradiation amount. Example 2 Synthesis was performed by the same synthetic process as in Example 1 using an o-cresol novolak type epoxy resin (epoxy equivalent: 215, having 6 phenol nuclei on average in one molecule). In a 2 liter separable flask, 411.4 g of ethyl carbitol acetate, 430 g of o-cresol novolak type epoxy resin and acrylic acid 14 were added.
4 g (2 mol) were charged. The mixture was heated to 120 ° C. with stirring, and the reaction was continued for 10 hours while maintaining the temperature at 120 ° C. Once the reaction product has cooled to room temperature, succinic anhydride 19
0 g (1.9 mol) was added, and the mixture was heated to 80 ° C. and reacted for 4 hours. Once again, the reaction product was cooled to room temperature. The acid value of the product solids was 139 mg KOH / g. 85.2 g of glycidyl methacrylate was added to this solution.
(0.6 mol) and 45.9 g of propylene glycol methyl ether acetate, and the mixture was stirred at 110 ° C.
The reaction was continued for 6 hours while maintaining the temperature at 110 ° C. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution was 65% by weight, and the acid value of the resin solid was 86 mgKOH / g. This solution is referred to as a resin solution A-2. 20 parts of resin solution A-1
Except that 20 g of the resin solution A-2 was used instead of using g, an etching photoresist ink composition was prepared in exactly the same manner as in Example 1, and was applied and processed on a copper foil substrate. The alkali developability, developer resistance and etchant resistance were evaluated. The photo-curing ability is as follows: Step 11, UV irradiation 3 when UV irradiation 100 mJ / cm ²
Step 12 was performed in the case of 00 mJ / cm ² . In the dilute alkali developability test, development was possible within one minute. In the developer resistance and etchant resistance tests, the coating film did not peel at all irrespective of the amount of UV irradiation. Example 3 Synthesis was carried out in the same manner as in Example 1 using bisphenol A novolak type epoxy resin [Yukaka Epoxy Co., Ltd., Epicoat 157S70, epoxy equivalent 210, softening point 70 ° C]. In a 2 liter separable flask, 432.6 g of butyl cellosolve, 420 g of bisphenol A novolak type epoxy resin and 144 g (2 mol) of acrylic acid were charged. 120 with stirring
C., and the reaction was continued for 10 hours while maintaining 120.degree. Once the reaction product was cooled to room temperature, 95 g (0.95 mol) of succinic anhydride and 144.4 g (0.95 mol) of tetrahydrophthalic anhydride were added, and the mixture was heated to 80 ° C. and reacted for 4 hours. Once again, the reaction product was cooled to room temperature. The acid value of this product solid is 132 mg.
KOH / g. 85.2 g (0.6 mol) of glycidyl methacrylate and butyl cellosolve 4 were added to this solution.
5.9 g was added and heated to 110 ° C. with stirring.
The reaction was continued for 6 hours while maintaining 0 ° C. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution was 65% by weight, and the acid value of the resin solid was 82 mgKOH / g. This solution is called resin solution A
-3. An etching photoresist ink composition was prepared in exactly the same manner as in Example 1 except that 20 g of the resin solution A-3 was used instead of using 20 g of the resin solution A-1, and coating and processing on a copper foil substrate were performed. Photocurability, dilute alkali developability, developer resistance and etchant resistance were evaluated. Photocurable the cases of UV dose 100 mJ / cm ² step 10, UV irradiation dose 300 mJ / cm ² it was step 12. In the dilute alkali developability test, 1
Development was possible within minutes. In the developer resistance and etchant resistance tests, the coating film did not peel at all irrespective of the amount of UV irradiation. Example 4 Using glycidyl acrylate, synthesis was performed in the same synthesis process as in Example 1. In a 2-liter separable flask, 389.3 g of butyl cellosolve, 471 g of a bisphenol A type epoxy resin having an epoxy equivalent of 471, a molecular weight of 900, a softening point of 64 ° C., and acrylic acid 7
2 g (1 mol) were charged. The mixture was heated to 120 ° C. with stirring, and the reaction was continued for 10 hours while maintaining the temperature at 120 ° C. Once the reaction product has cooled to room temperature, succinic anhydride 18
0 g (1.8 mol) was added, and the mixture was heated to 80 ° C. and reacted for 4 hours. Once again, the reaction product was cooled to room temperature. The acid value of the product solids was 139 mg KOH / g. 76.8 g of glycidyl acrylate was added to this solution.
(0.6 mol) and 42 g of butyl cellosolve,
The mixture was heated to 110 ° C. with stirring, and the reaction was continued for 6 hours while maintaining 110 ° C. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution was 65% by weight, and the acid value of the resin solid was 84 mgKOH /
g. This solution is referred to as a resin solution A-4. Instead of using 20 g of the resin solution A-1, 2
Except that 0 g was used, an etching photoresist ink composition was prepared in exactly the same manner as in Example 1, applied to a copper foil substrate, processed, and then subjected to photocuring, dilute alkali developability, developer resistance, and etching resistance. The liquid properties were evaluated. The photocurability is determined by the step 9, U when the UV irradiation amount is 100 mJ / cm ^2.
Step 11 was performed when the V irradiation amount was 300 mJ / cm ² . In the dilute alkali developability test, development was possible within one minute. In the developer resistance and etchant resistance tests,
The coating film did not peel off at all regardless of the amount of UV irradiation. Example 5 Synthesis was carried out using allyl glycidyl ether by the same synthesis process as in Example 1. A 2-liter separable flask was charged with 414.5 g of propylene glycol methyl ether acetate, 471 g of a bisphenol A type epoxy resin having an epoxy equivalent of 471, a molecular weight of 900, and a softening point of 64 ° C., and 72 g (1 mol) of acrylic acid. The mixture was heated to 120 ° C. with stirring, and the reaction was continued for 10 hours while maintaining the temperature at 120 ° C. Once the reaction product has cooled to room temperature, 90 g (0.9 mol) of succinic anhydride and 136.8 g (0.9 mol) of tetrahydrophthalic anhydride are obtained.
Was added, and the mixture was heated to 80 ° C. and reacted for 4 hours. Again,
The reaction product was cooled to room temperature. The acid value of this product solid was 131 mg KOH / g. 68.4 g (0.6 mol) of allyl glycidyl ether and 36.8 g of ethyl carbitol acetate were added to this solution, and the mixture was heated to 110 ° C. with stirring, and the reaction was continued for 6 hours while maintaining 110 ° C. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution is 65
% By weight, and the acid value of the resin solids was 80 mgKOH / g. This solution is referred to as a resin solution A-5. Resin solution A
An etching photoresist ink composition was prepared in exactly the same manner as in Example 1 except that 20 g of the resin solution A-5 was used instead of using 20 g of -1 and applied and processed on a copper foil substrate to obtain a photocurable resin. , Diluted alkali developing property, developing solution resistance and etching solution resistance were evaluated. Light curability is U
For the case of V dose 100 mJ / cm ² step 7, UV irradiation dose 300 mJ / cm ² was step 9. In the dilute alkali developability test, development was possible within one minute. In the developer resistance test, the coating film did not peel at all irrespective of the amount of UV irradiation. In the etching resistance test, when the UV irradiation amount was 100 mJ / cm ² , the coating film was peeled off by about 1%.
When the V irradiation amount was 300 mJ / cm ² , the coating film did not peel off at all. Example 6 Using 3,4-epoxycyclohexylmethyl acrylate represented by the formula [2], synthesis was performed in the same synthesis process as in Example 1.

Embedded image In a 2 liter separable flask, 414.5 g of ethyl carbitol acetate, 471 g of bisphenol A type epoxy resin having an epoxy equivalent of 471, a molecular weight of 900, and a softening point of 64 ° C., and 72 g (1 mol) of acrylic acid
Was charged. Heat to 120 ° C with stirring, 120 ° C
The reaction was continued for 10 hours while maintaining the temperature. Once the reaction product was cooled to room temperature, 90 g (0.9 mol) of succinic anhydride and 136.8 g (0.9 mol) of tetrahydrophthalic anhydride were used.
9 mol), and the mixture was heated to 80 ° C. and reacted for 4 hours. Once again, the reaction product was cooled to room temperature. The acid value of this product solid was 131 mg KOH / g. 3,4-Epoxycyclohexylmethyl acrylate [Daicel Chemical Industries, Ltd., Cyclomer A20]
0] 91 g (0.5 mol) and 49 g of ethyl carbitol acetate were added, and the mixture was heated to 110 ° C with stirring, and the reaction was continued for 6 hours while maintaining 110 ° C. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution was 65% by weight, and the acid value of the resin solid was 85 mgKOH / g. This solution is referred to as a resin solution A-6. An etching photoresist ink composition was prepared in exactly the same manner as in Example 1 except that 20 g of the resin solution A-6 was used instead of using 20 g of the resin solution A-1, and applied and processed on a copper foil substrate. Light curable,
Evaluation was made on dilute alkali developability, developer resistance, and etchant resistance. The photo-curing ability is based on a UV irradiation amount of 100 mJ /
For cm ² Step 8, when the UV dose 300 mJ / cm ² was step 10. In the dilute alkali developability test,
Development was possible in 1 minute and 20 seconds. In the developer resistance and etchant resistance tests, the coating film did not peel at all irrespective of the amount of UV irradiation. Comparative Example 1 Synthesis was performed by the same synthetic route as in Example 1 except that the addition reaction of glycidyl methacrylate of Example 1 was not performed. In a 2-liter separable flask, 360.2 g of ethyl carbitol acetate and an epoxy equivalent of 47 were added.
1, 471 g of a bisphenol A type epoxy resin having a molecular weight of 900 and a softening point of 64 ° C., and 72 g of acrylic acid (1
Mol). Heat to 120 ° C with stirring,
The reaction was continued for 10 hours while maintaining the temperature at 20 ° C. Once the reaction product was cooled to room temperature, 50 g of succinic anhydride (0.
5 mol) and 76 g of tetrahydrophthalic anhydride (0.
5 mol), and the mixture was heated to 80 ° C. and reacted for 4 hours. When the reaction product was cooled to room temperature, a viscous solution was obtained. The heating residue of this solution was 65% by weight, and the acid value of the resin solid was 84 mgKOH / g. This solution is referred to as a resin solution B-1. The heating residue of the resin solution B-1 has the same value as the heating residue of the resin solutions A-1 to A-6, and the acid value of the resin in the resin solution B-1 is the same as that of the resin solution A-1.
This is almost the same as the acid value of the resin in A-6. Instead of using 20 g of the resin solution A-1, 2 parts of the resin solution B-1 were used.
Except that 0 g was used, an etching photoresist ink composition was prepared in exactly the same manner as in Example 1, applied to a copper foil substrate, processed, and then subjected to photocuring, dilute alkali developability, developer resistance, and etching resistance. The liquid properties were evaluated. The photo-curing ability was measured in Step 2, U when the UV irradiation amount was 100 mJ / cm ^2.
Step 6 was performed when the V irradiation amount was 300 mJ / cm ² .
In the dilute alkali developability test, development took 4 minutes and 10 seconds. In the developer resistance test, the UV irradiation amount was 100 mJ / cm ²
In the case of, the coating film is peeled off by about 25%, and the UV irradiation amount is 300 mJ /
In the case of cm ² , about 5% of the coating film was peeled off. In the etching resistance test, when the UV irradiation amount was 100 mJ / cm ² , the coating film was peeled off by about 50%, and when the UV irradiation amount was 300 mJ / cm ² , the coating film was peeled off by about 20%. Examples 1 to 6 and Comparative Example 1
Table 1 summarizes the results.

[0010]

[Table 1]

The etching resist inks based on the photocurable resin of the present invention in Examples 1 to 6 all have good photocurability and good alkali developability, developer resistance, and etchant resistance. Is shown. In contrast, the etching resist ink based on the unsaturated group-containing polycarboxylic acid resin generally used in Comparative Example 1 has low photocurability, and the resist coating is damaged during alkali development or copper etching. doing.

[0012]

The photocurable resin of the present invention has excellent photocurability and, when used in a photoresist ink for etching, has good dilute alkali developability and good durability against a developing solution and an etching solution. .

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-26183 (JP, A) JP-A-3-290428 (JP, A) JP-A-3-191352 (JP, A) JP-A-49-197 16788 (JP, A) JP-A-7-199457 (JP, A) JP-A-5-281741 (JP, A) JP-A-63-205650 (JP, A) JP-A-7-207211 (JP, A) JP-A-6-348009 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03F 7/027 C08F 299/02

Claims (4)

(57) [Claims] 1. A carboxyl group of a resin having a radical polymerizable unsaturated acyl group and a carboxyl group obtained by reacting a radical polymerizable unsaturated monocarboxylic acid with an epoxy resin and further reacting a dibasic acid anhydride. Based on 1
A photocurable resin obtained by reacting one epoxy group with a compound having one or more radically polymerizable unsaturated groups. 2. The resin having a radical polymerizable unsaturated acyl group and a carboxyl group has an acid value of 80 to 170 mg KOH / g.
The photocurable resin according to claim 1, wherein 3. A resin having a radically polymerizable unsaturated acyl group and a carboxyl group has a ratio of 1 to 1 mol per carboxyl group.
3. The photocurable resin according to claim 1, wherein 0.1 to 0.5 mol of a compound having one or more epoxy groups and one or more radically polymerizable unsaturated groups is reacted. 4. The photocurable resin according to claim 1, wherein the acid value is 40 to 110 mgKOH / g.