JP2981218B1 - Solder photoresist ink composition - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To significantly improve the flexibility of a cured film of a dilute alkali developing type solder photoresist ink composition containing a conventional photocurable resin, to be applicable to a flexible substrate, and to be an important performance as a resist ink. A solder photoresist ink composition which is excellent in dilute alkali developability, solder heat resistance, and especially pressure cooker resistance. A compound having two or more hydroxyl groups and one or more carboxyl groups (a), a bifunctional or higher polyisocyanate having a six-membered ring structure (b), and a (meth) acrylate having a hydroxyl group (c) ), A carboxyl group-containing urethane acrylate (A), a polybasic anhydride-modified epoxy acrylate resin (B), a photopolymerization initiator (C), a difunctional or higher epoxy resin (D), and a diluent. A solder photoresist ink composition containing (E).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a solder photoresist ink composition. More specifically, the present invention provides a composition in a liquid form, having excellent photocurability,
The present invention relates to a solder photoresist ink composition which can be developed with a dilute aqueous alkali solution during the production of a printed wiring board, and whose cured product has excellent flexibility and resistance to pressure cooker.

[0002]

2. Description of the Related Art At present, solder resists for various printed wiring boards are shifting from screen-printed thermosetting type liquid resist resins and dry film type resist resins to dilute alkali developing type liquid solder photoresist inks. . For example, Japanese Patent Publication No. 1-54390 discloses a novolak-type epoxy compound as a liquid resist ink composition having excellent photocurability, thermosetting property, heat resistance, solvent resistance, and acid resistance, and developable with an alkaline aqueous solution. A reaction product with an unsaturated monocarboxylic acid, a photocurable resin obtained by reacting a saturated or unsaturated polybasic acid anhydride, a photopolymerization initiator, a diluent and an epoxy compound having two or more epoxy groups. A liquid resist ink composition comprising the same has been proposed. However, the solder resist ink composition based on such a novolak type epoxy resin has excellent heat resistance in its structure, but the cured film is hard and brittle, and the adhesion between the coated film and the substrate is poor. There is a disadvantage that. Therefore, the use of such a resist ink composition is limited to a rigid substrate such as a glass epoxy substrate which does not require the flexibility of a cured film. However, in recent years, the use of thin and flexible wiring boards (flexible boards) using polyester films or polyimide films has been increasing for the purpose of simplifying the processing steps and reducing the size and density of the boards. Therefore, a flexible solder resist ink composition is required. In order to satisfy this demand, many proposals have recently been made as resist ink compositions having flexibility. For example, Japanese Patent Application Laid-Open No. Hei 7-207211 discloses a resist ink composition for a flexible printed wiring board having excellent developability photosensitivity and excellent in bending resistance and folding resistance, which is incompatible with bisphenol A type epoxy resin. There has been proposed a resist ink composition containing a polycarboxylic acid resin having an unsaturated group, which is a reaction product of a saturated monocarboxylic acid and succinic anhydride, a photopolymerization initiator, a diluent, and a curing component. JP-A-8-134390 discloses a resist ink composition for a flexible printed wiring board which is excellent in developability in a dilute alkaline aqueous solution and the obtained cured product is excellent in bending resistance and folding resistance. A resist ink composition containing a polycarboxylic acid resin having an unsaturated group, which is a reaction product of an epoxy resin, an unsaturated monocarboxylic acid, and a dibasic acid anhydride, a photopolymerization initiator, a diluent, and a curing component is proposed. Have been. Japanese Patent Application Laid-Open No. 9-54434 discloses that a fine image can be formed, a cured film is rich in flexibility, solder heat resistance, heat deterioration resistance, electroless gold plating resistance, and the like.
As an alkali developing type curable resin composition capable of forming a film having excellent acid resistance and water resistance, bisphenol type 2
A composition comprising a photosensitive epoxy resin obtained by reacting (meth) acrylic acid and an acid anhydride with a functional epoxy resin, a diglycidyl ether type epoxy resin, a photopolymerization initiator and a diluent has been proposed. . Also, Japanese Patent Application Laid-Open No. 9-529
No. 25 discloses pressure cooker resistance, heat resistance,
A photopolymerizable resin composition containing a urethane-modified vinyl ester resin or a urethane-modified acid-added vinyl ester resin and a photopolymerization initiator has been proposed as a resin having an adhesive property to a substrate. JP-A-8-269172 discloses a photosensitive thermosetting resin composition having excellent developability and sensitivity, having resistance to a developing solution in an exposed portion, and having a long pot life, comprising an epoxy compound and an unsaturated monocarboxylic acid. It contains a photosensitive prepolymer having two or more ethylenically unsaturated bonds, such as an esterified product formed by the reaction, a photopolymerization initiator, a diluent, an epoxy compound hardly soluble in the diluent, and a curing agent for epoxy resin. Thermosetting resin compositions have been proposed. Furthermore, JP-A-6-206956 discloses that a radiation-curable resin composition which can be dissolved in a dilute aqueous alkali solution and has a cured product excellent in water resistance, solvent resistance, and chemical resistance is one or more. Radiation containing urethane (meth) acrylate which is a reaction product of a compound having a carboxyl group and two or more hydroxyl groups, a polyisocyanate and a (meth) acrylate having a hydroxyl group, a reactive diluent and a photopolymerization initiator Curable resin compositions have been proposed. High-resolution, easy to develop with trichloroethane-based organic solvent or alkaline aqueous solution, excellent solvent resistance to trichlorethylene, acetone, etc., excellent plating solution resistance to electroless plating, and manufacture of printed wiring boards with heat resistance JP-A-7-248622 describes a permanent resist resin composition as
A resin composition comprising a urethane (meth) acrylate compound having at least two isocyanate groups, a diluent comprising a reactive monomer and a photopolymerization initiator has been proposed.
No. 247330 discloses a urethane (meth) acrylate compound having one or more isocyanate groups, epoxy
A resin composition comprising a (meth) acrylate compound, a diluent comprising a reactive monomer, and a photopolymerization initiator has been proposed. Japanese Patent Application Laid-Open No. 8-292569 discloses a photosensitive resin composition having good workability, flexibility and soldering heat resistance, having a diisocyanate compound and a hydroxyl group in a polycarbonate compound having hydroxyl groups at both ends. There has been proposed a photosensitive resin composition which can be developed with an alkaline aqueous solution containing a urethane compound obtained by reacting an ethylenically unsaturated compound, a thermoplastic polymer having a carboxyl group, and a photopolymerization initiator. JP 9
No. 5,597,997 discloses a photosensitive resin composition capable of forming a flexible solder resist film, a mixture of a novolak epoxy resin and a rubber-modified bisphenol A type epoxy resin, an unsaturated carboxylic acid and a polybasic acid anhydride. There has been proposed a photosensitive resin composition containing a photosensitive prepolymer comprising a reaction product with a product, a photopolymerizable reactive diluent, a photopolymerization initiator, and a thermosetting component. By using these resin compositions, it is possible to obtain a flexible film, but other properties required for the resist ink composition, for example, dilute alkali developability, solder heat resistance, and even the substrate The pressure cooker resistance, which is an important performance factor for reliability, is still insufficient, and a resist ink composition having these characteristics widely has been demanded.

[0003]

DISCLOSURE OF THE INVENTION The present invention significantly improves the flexibility of a cured film of a dilute alkali development type solder photoresist ink composition containing a conventional photocurable resin and makes it applicable to a flexible substrate. It is another object of the present invention to provide a solder photoresist ink composition that is excellent in dilute alkali developability and solder heat resistance, which are important properties as a resist ink, and particularly excellent in pressure cooker resistance.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, the photocurable resin has two or more hydroxyl groups and one or more carboxyl groups. Use of a compound, a urethane acrylate having a carboxyl group obtained by reacting a bifunctional or more functional polyisocyanate having a 6-membered ring structure and a (meth) acrylate having a hydroxyl group with a polybasic anhydride-modified epoxy acrylate resin. Thereby, a composition excellent in dilute alkali developability is obtained, and the cured film is found to have excellent flexibility, adhesion, solder heat resistance and pressure cooker resistance. It was completed. That is, the present invention provides (1) a compound (a) having two or more hydroxyl groups and one or more carboxyl groups, a bifunctional or higher polyisocyanate having a six-membered ring structure (b), and a hydroxyl group ( Urethane acrylate having a carboxyl group obtained by reacting (meth) acrylate (c) (A), polybasic acid anhydride-modified epoxy acrylate resin (B), photopolymerization initiator (C), difunctional or higher epoxy resin ( D) and a diluent (E), a solder photoresist ink composition comprising: (2) a compound having two or more hydroxyl groups and one or more carboxyl groups (a) is dimethylol butane; The solder photoresist ink composition according to item (1), which is an acid or dimethylolpropionic acid, (3) bifunctional or more having a 6-membered ring structure Is a group consisting of diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, tolylene diisocyanate, polymeric diphenyl methane diisocyanate, naphthalene diisocyanate, tetramethyl xylylene diisocyanate, and norbornane diisocyanate Item (1), which is one or more compounds selected from the group consisting of: (4) a urethane acrylate having a carboxyl group (A) having two or more hydroxyl groups and one A compound having a carboxyl group (a), a bifunctional or higher polyisocyanate having a 6-membered ring structure (b), and a hydroxyl group That (meth) acrylate (c) and a polyol compound having two or more hydroxyl groups (d) is obtained by reacting the (1)
Item (5): A solder photoresist ink composition according to Item (5).
Polybasic acid anhydride-modified epoxy acrylate resin (B)
Is a resin having a radical polymerizable unsaturated acyl group and a carboxyl group, obtained by reacting a radical polymerizable unsaturated monocarboxylic acid with a novolak type epoxy resin and further reacting a dibasic acid anhydride. Item 1), wherein the weight ratio of the urethane acrylate having a carboxyl group (A) to the polybasic acid anhydride-modified epoxy acrylate resin (B) is 2: 8 to 8: 2. (1) a content of the photopolymerization initiator (C), wherein the content of the photopolymerization initiator (C) is a urethane acrylate (A) having a carboxyl group and a polybasic acid anhydride-modified epoxy acrylate resin ( The solder photoresist ink composition according to item (1), wherein the amount is 0.2 to 20 parts by weight per 100 parts by weight of the total amount of B), (8) bifunctional The content of the epoxy resin (D) is 5 to 60 parts by weight per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B). Item 1), the solder photoresist ink composition, and (9) the diluent (E) is one or more compounds selected from photopolymerizable monomers and organic solvents, and the content is 30 to 2 per 100 parts by weight of the total amount of the urethane acrylate having a carboxyl group (A) and the polybasic acid anhydride-modified epoxy acrylate resin (B)
A solder photoresist ink composition according to item (1), wherein the amount is 00 parts by weight. Further, as a preferred embodiment of the present invention, (10) a compound (a) having two or more hydroxyl groups and one or more carboxyl groups, a bifunctional or higher polyisocyanate having a 6-membered ring structure (b), and a hydroxyl group In the urethane acrylate (A) having a carboxyl group obtained by reacting the (meth) acrylate (c) having the following formula, the total of the hydroxyl groups of the compound (a) and the (meth) acrylate (c) is added to the polyisocyanate (b) ) Has an isocyanate group molar ratio of 0.9: 1.1 to 1.2: 0.8.
(1) a compound having two or more hydroxyl groups and one or more carboxyl groups (a), a bifunctional or more polyfunctional compound having a 6-membered ring structure, In a urethane acrylate (A) having a carboxyl group obtained by reacting an isocyanate (b) and a (meth) acrylate having a hydroxyl group, a hydroxyl group of the (meth) acrylate (c) having a hydroxyl group and a 6-membered ring structure Wherein the molar ratio of the isocyanate groups of the difunctional or higher polyisocyanate (b) having the formula (b) is 0.2: 1.0 to 0.5: 1.0.
(1) The solder photoresist ink composition according to (1),
(12) Compound (a) having two or more hydroxyl groups and one or more carboxyl groups, 2 having a six-membered ring structure
In a urethane acrylate (A) having a carboxyl group obtained by reacting a polyisocyanate (b) having a functionality higher than or equal to a (meth) acrylate (c) having a hydroxyl group, the acid value of the urethane acrylate (A) is 50 to 100 mgKOH / g. Item 1), a solder photoresist ink composition according to item 1, (13) a compound having two or more hydroxyl groups and one or more carboxyl groups (a), and a bifunctional or more functional polyisocyanate having a six-membered ring structure (b). , A (meth) acrylate having a hydroxyl group (c) and a urethane acrylate having a carboxyl group (A) obtained by reacting a polyol compound (d) having two or more hydroxyl groups with a compound (a) and (meth) ) The total of the hydroxyl groups of the acrylate (c) and the polyol compound (d), The molar ratio of isocyanate groups contained in the anate (b) is from 0.9: 1.1 to 1.2: 0.1.
(4) a compound having two or more hydroxyl groups and one or more carboxyl groups (a), a bifunctional or more functional compound having a 6-membered ring structure, In a urethane acrylate (A) having a carboxyl group obtained by reacting a polyisocyanate (b), a (meth) acrylate (c) having a hydroxyl group and a polyol compound (d) having two or more hydroxyl groups, Value is 50-100mg
(15) The solder photoresist ink composition according to (4), wherein the polyol compound having two or more hydroxyl groups (d) is a compound having three or more hydroxyl groups. (4) The solder photoresist ink composition according to (4), and (16) the solder compound according to (4), wherein the polyol compound (d) having two or more hydroxyl groups is a compound having a 6-membered ring structure. And a resist ink composition.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The solder photoresist ink composition of the present invention comprises a compound (a) having two or more hydroxyl groups and one or more carboxyl groups, a bifunctional or higher polyisocyanate having a six-membered ring structure. (B) and a carboxyl group-containing urethane acrylate (A) obtained by reacting a hydroxyl group-containing (meth) acrylate (c), a polybasic acid anhydride-modified epoxy acrylate resin (B), a photopolymerization initiator (C) ) Containing a bifunctional or higher functional epoxy resin (D) and a diluent (E).
In the present invention, the compound (a) having two or more hydroxyl groups and one or more carboxyl groups is not particularly limited. For example, dimethylolbutanoic acid, dimethylolpropionic acid, or a trifunctional or higher functional polyol compound may be used. Reaction products with polybasic acid anhydrides can be mentioned.
One of these compounds having two or more hydroxyl groups and one or more carboxyl groups can be used alone or in combination of two or more. Among these, compounds having no ester bond such as dimethylolbutanoic acid and dimethylolpropionic acid are excellent in pressure cooker resistance of a coating film obtained from a solder photoresist ink composition, so that they can be particularly preferably used. it can. In the present invention, the bifunctional or higher polyisocyanate (b) having a 6-membered ring structure is not particularly limited. For example, diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (H12MDI), isophorone diisocyanate (IPDI), xylylene diisocyanate ( XD
I), hydrogenated xylylene diisocyanate (H6XD
I), tolylene diisocyanate (TDI), polymeric diphenylmethane diisocyanate (PMDI),
Examples include naphthalene diisocyanate (NDI), tetramethylxylylene diisocyanate, norbornane diisocyanate, and the like. One of these bifunctional or higher polyisocyanates having a 6-membered ring structure can be used alone, or two or more can be used in combination.

In the present invention, a compound having a hydroxyl group
There is no particular limitation on the (meth) acrylate (c).
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, polyethylene glycol mono
(Meth) acrylate, pentaerythritol tri (meth)
Examples include acrylate, glycerin di (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, cyclohexanedimethanol mono (meth) acrylate, and N-methylol (meth) acrylamide. In the present invention, the total of the compound (a) having two or more hydroxyl groups and one or more carboxyl groups and the hydroxyl group of the (meth) acrylate (c) having a hydroxyl group, and a compound having a six-membered ring structure Molar ratio of isocyanate groups of polyisocyanate (b) having functional or higher functionality ([OH] _{a + c} : [NCO] _b )
Is preferably 0.9: 1.1 to 1.2: 0.8. When [OH] _{a + c} : [NCO] _b is less than 0.9: 1.1, there is a possibility that the solder photoresist ink composition may thicken with time due to the remaining isocyanate groups. [OH] _{a + c} : When [NCO] _b exceeds 1.2: 0.8,
There is a possibility that the ratio of the low molecular weight component increases, and the solder heat resistance and the pressure cooker resistance of the cured resist ink coating film decrease. In the present invention, the molar ratio of the hydroxyl group of the (meth) acrylate (c) having a hydroxyl group to the isocyanate group of the polyisocyanate (b) having a 6-membered ring structure ([OH] _c : [NCO] _b )
Preferably, the ratio is 0.2: 1.0 to 0.5: 1.0.
When [OH] _c : [NCO] _b is less than 0.2: 1.0, the amount of radically polymerizable unsaturated groups in the urethane acrylate (A) having a carboxyl group is small, and curing by ultraviolet rays is insufficient. Could be [OH] _c : [NCO] _b
If the ratio exceeds 0.5: 1.0, the molecular weight of the urethane acrylate (A) having a carboxyl group becomes low, and the film formability of the solder photoresist ink composition may be reduced. In the present invention, a compound (a) having two or more hydroxyl groups and one or more carboxyl groups,
The acid value of a urethane acrylate having a carboxyl group (A) obtained by reacting a bifunctional or more functional polyisocyanate having a 6-membered ring structure (b) and a (meth) acrylate having a hydroxyl group (c) is 50 to 100 mg KO.
H / g is preferred. When the acid value of the urethane acrylate (A) having a carboxyl group is less than 50 mgKOH / g, the diluted alkali developability of the solder photoresist ink composition may be reduced. When the acid value of urethane acrylate (A) exceeds 100 mgKOH / g,
There is a possibility that the electrical properties of the cured coating film of the solder photoresist ink composition and the resistance to pressure cooker may be reduced.

In the present invention, a urethane acrylate (A) having a carboxyl group is converted to a compound (a) having two or more hydroxyl groups and one or more carboxyl groups, a bifunctional or higher polyfunctional compound having a six-membered ring structure. It can be obtained by reacting isocyanate (b), (meth) acrylate (c) having a hydroxyl group, and polyol compound (d) having two or more hydroxyl groups. There is no particular limitation on the polyol compound having two or more hydroxyl groups, for example, a polyether-based polyol, a polyester-based polyol, a polyol compound having two relatively large hydroxyl groups such as a polybutadiene-based polyol, Polyol compounds having two hydroxyl groups having a small molecular weight such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, and neopentyl glycol, cyclohexane dimethanol, a 2-mol ethylene oxide adduct of bisphenol A, and bisphenol S Polyol compounds having a 6-membered ring structure such as ethylene oxide 2 mol adduct, polyol compounds having three hydroxyl groups such as trimethylolpropane and glycerin, pentae 4 such as risuritol
And a polyol compound having one hydroxyl group. Among these, a polyol compound having a six-membered ring structure and a polyol compound having three or more hydroxyl groups can be suitably used because they increase the strength of a cured film of a solder photoresist ink. When reacting a polyol compound (d) having two or more hydroxyl groups, a compound (a) having two or more hydroxyl groups and one or more carboxyl groups and a (meth) acrylate (c) having a hydroxyl group ) And the total hydroxyl groups of the polyol compound (d) having two or more hydroxyl groups and the molar ratio of the isocyanate groups of the bifunctional or higher polyisocyanate (b) having a 6-membered ring structure ([OH] _{a + c + d} : [NC
O] _b ) is preferably from 0.9: 1.1 to 1.2: 0.8. [OH] _{a + c + d} : When [NCO] _b is less than 0.9: 1.1, the remaining photoresist isocyanate group may increase the viscosity of the solder photoresist ink composition over time. . [OH] _{a + c + d} : When [NCO] _b exceeds 1.2: 0.8, the ratio of low molecular weight components increases, and the solder heat resistance and pressure cooker resistance of the cured resist ink coating film decrease. There is a possibility that. The acid value of the resulting urethane acrylate having a carboxyl group (A) is 5
Preferably it is 0 to 100 mgKOH / g. The acid value of the urethane acrylate (A) having a carboxyl group is 5
If it is less than 0 mgKOH / g, the diluted alkali developability of the solder photoresist ink composition may be reduced. The acid value of urethane acrylate (A) is 100mgKOH
If it exceeds / g, the electrical properties of the cured coating film of the solder photoresist ink composition and the pressure cooker resistance may be reduced.

In the present invention, there is no particular limitation on the reaction order of the starting compounds in the production of the urethane acrylate (A) having a carboxyl group. For example, a compound having two or more hydroxyl groups and one or more carboxyl groups (A) a bifunctional or higher polyisocyanate having a 6-membered ring structure (b) and a (meth) acrylate (c) having a hydroxyl group, or a compound having two or more hydroxyl groups and one or more carboxyl groups (A), a bifunctional or higher polyisocyanate having a 6-membered ring structure (b), a hydroxyl group-containing (meth) acrylate (c) and 2
A polyol compound having two or more hydroxyl groups (d) can be simultaneously charged into a reaction vessel and can be produced by a so-called one-shot method, or a compound having two or more hydroxyl groups and one or more carboxyl groups (a ) And a bifunctional or higher polyisocyanate (b) having a 6-membered ring structure, and then reacting with (meth) acrylate (c) having a hydroxyl group or (meth) acrylate (c) having a hydroxyl group. The above-mentioned polyol compound (d) having a hydroxyl group can be added and reacted. When the reactivities of the starting compounds used are different, the starting compounds having low reactivity can be reacted first. In the present invention, a compound (a) having two or more hydroxyl groups and one or more carboxyl groups and a (meth) acrylate (c) having a hydroxyl group, or two or more hydroxyl groups and one or more carboxyl groups A compound having a group (a), a (meth) acrylate having a hydroxyl group (c), and a polyol compound having two or more hydroxyl groups (d);
The reaction temperature with the bifunctional or higher polyisocyanate (b) having a membered ring structure is preferably from 50 to 100 ° C, more preferably from 55 to 85 ° C. At the time of the reaction, it is preferable to add a polymerization inhibitor such as hydroquinone and hydroquinone monomethyl ether in order to prevent thermal polymerization of the (meth) acrylate having a hydroxyl group. Further, for promoting the reaction between the isocyanate group and the hydroxyl group, for example, a tin-based or amine-based catalyst can be added.

In the present invention, a compound (a) having two or more hydroxyl groups and one or more carboxyl groups and a (meth) acrylate (c) having a hydroxyl group,
Or a compound (a) having two or more hydroxyl groups and one or more carboxyl groups, having a hydroxyl group
The reaction of the (meth) acrylate (c) and the polyol compound (d) having at least two hydroxyl groups with the bifunctional or more functional polyisocyanate (b) having a 6-membered ring structure should be performed in a reaction diluent. Can be. As the reaction diluent, a photopolymerizable monomer or an organic solvent can be used. The amount of the reaction diluent is 20 to the total weight of the reaction system.
Preferably, it is about 50% by weight. Examples of the photopolymerizable monomer that can be used as a reaction diluent include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl
(Meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl
(Meth) acrylate, phenoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, benzyl (meth) acrylate, monofunctional acrylate compounds such as ethyl carbitol (meth) acrylate and , Ethylene glycol di
(Meth) acrylate, polyethylene glycol di (meth)
Polyfunctional acrylates such as acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate Can be mentioned. Note that (meth) acrylate indicates both acrylate and methacrylate. Examples of the organic solvent that can be used as the reaction diluent include, for example, methyl ethyl ketone, ketones such as cyclohexanone, toluene, aromatic hydrocarbons such as xylene, cyclohexane, alicyclic hydrocarbons such as methylcyclohexane, petroleum ether, Examples thereof include petroleum solvents such as petroleum naphtha, and acetates such as ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, and butyl carbitol acetate.

The polybasic acid anhydride-modified epoxy acrylate resin (B) used in the present invention is obtained by reacting a novolak type epoxy resin with a radically polymerizable unsaturated monocarboxylic acid and further reacting a dibasic acid anhydride. Obtainable. The novolak type epoxy resin to be used is not particularly limited, and examples thereof include a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, and a bisphenol A novolak type epoxy resin. The reaction of the novolak type epoxy resin with the radically polymerizable unsaturated monocarboxylic acid cleaves the oxirane ring of the epoxy resin to generate 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, crotonic acid, vinyl acetic acid, sorbic acid, and cinnamic acid. Among them, acrylic acid and methacrylic acid can be particularly preferably used because they have good reactivity with the epoxy resin and the obtained solder photoresist ink composition has excellent ultraviolet curability. In the present invention, the unsaturated monocarboxylic acid is
One kind may be used alone, or two or more kinds may be used in combination. The novolak-type epoxy resin and the radically polymerizable unsaturated monocarboxylic acid are preferably reacted in approximately equivalent amounts. The reaction between the novolak type epoxy resin and the unsaturated monocarboxylic acid can be carried out by heating in a reaction diluent as in the production of the urethane acrylate (A) having a carboxyl group. As the reaction diluent, the same reaction diluents as those exemplified for the production of the urethane acrylate (A) having a carboxyl group can be used. The amount of the reaction diluent used is 20 to 50% by weight based on the total weight of the reaction system.
It is preferred that The reaction temperature of the novolak type epoxy resin and the unsaturated monocarboxylic acid is 100 to 12
Preferably it is 0 ° C.

The reaction product of the novolak type epoxy resin and the radically polymerizable unsaturated monocarboxylic acid is then reacted with a dibasic acid anhydride. As the dibasic acid anhydride, any of a saturated dibasic acid anhydride and an unsaturated dibasic acid anhydride can be used. Examples of the dibasic anhydride used include, for example, succinic anhydride, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and endmethylenetetrahydro. Phthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride,
Chlorendic anhydride and the like can be mentioned. One type of dibasic acid anhydride can be used alone, or two or more types can be used in combination. Among these, succinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, and methyltetrahydrophthalic anhydride can be particularly preferably used. 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 amount of the dibasic acid anhydride to be reacted is preferably 0.3 to 1.0 mol per 1 mol of the hydroxyl group of the above reaction product. When the amount of the dibasic acid anhydride to be reacted is less than 0.3 mol per 1 mol of the hydroxyl group of the reaction product, development with a diluted alkaline aqueous solution may be difficult as a solder photoresist ink composition. .
When the amount of the dibasic acid anhydride to be reacted exceeds 1.0 mol per mol of the hydroxyl group of the reaction product, unreacted dibasic acid anhydride remains, and the storage stability of the solder photoresist ink composition becomes stable. And the pressure cooker resistance of the cured film of the solder photoresist ink may be reduced.

In the present invention, the dibasic acid anhydride is preferably added to the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid and reacted. When the reaction product is present as a diluent solution, a mixture of dibasic acid anhydrides is added to the solution, and the mixture is heated and dissolved to cause a reaction, whereby the reaction can be suitably advanced. The reaction temperature is preferably from 70 to 100 ° C. The polybasic anhydride-modified epoxy acrylate resin (B) obtained by reacting a dibasic anhydride with the reaction product of the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid thus obtained has an acid value of It is preferably 60 to 140 mgKOH / g. The acid value of the resulting polybasic acid anhydride-modified epoxy acrylate resin (B) can be easily adjusted by appropriately selecting the amount of the dibasic acid anhydride to be reacted. In the present invention, the mixing ratio of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B) is 2: 8 to weight ratio.
Preferably, the ratio is 8: 2. If the mixing ratio of the urethane acrylate having a carboxyl group (A) and the polybasic anhydride-modified epoxy acrylate resin (B) is less than 2: 8 (weight ratio), the flexibility of the solder photoresist ink cured film and Pressure cooker resistance may decrease. When the mixing ratio of the urethane acrylate having a carboxyl group (A) and the polybasic acid anhydride-modified epoxy acrylate resin (B) exceeds 8: 2 (weight ratio), the heat resistance of the solder photoresist ink cured film and the dilute alkali Developability may be reduced.

In the solder photoresist ink composition of the present invention, the photopolymerization initiator (C) to be used is not particularly limited, and a conventionally known photopolymerization initiator which decomposes by light irradiation to generate radicals is used. For example, benzoin, benzoins such as benzoin methyl ether, benzophenone, methylbenzophenone,
Benzophenones such as 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenyl Ketones, acetophenones such as N, N-dimethylaminoacetophenone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-methylanthraquinone, 2-ethylanthraquinone, −
Chloroanthraquinone, 2-amylanthraquinone, 2
Anthraquinones such as aminoanthraquinone, 2,
Thioxanthones such as 4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone and 2-isopropylthioxanthone, and ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal can be exemplified. . These photopolymerization initiators,
One kind may be used alone, or two or more kinds may be used in combination. In addition to these photopolymerization initiators, photopolymerization accelerators such as benzoic acids and tertiary amines can be used in combination. The content of the photopolymerization initiator (C) is 0.2 to 100 parts by weight of the total amount of the urethane acrylate having a carboxyl group (A) and the polybasic acid anhydride-modified epoxy acrylate resin (B).
It is preferably 20 parts by weight, more preferably 1 to 10 parts by weight. When the content of the photopolymerization initiator (C) is less than 0.2 parts by weight per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic acid anhydride-modified epoxy acrylate resin (B). The photocurability of the solder photoresist ink composition may be reduced. When the content of the photopolymerization initiator (C) exceeds 20 parts by weight per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic acid anhydride-modified epoxy acrylate resin (B), the cured coating is obtained. The pressure cooker resistance of the film may be reduced.

The bifunctional or higher functional epoxy resin (D) used in the present invention is not particularly limited. For example, bisphenol A epoxy resin, bisphenol F epoxy resin, novolak epoxy resin, polyglycidylamines, alicyclic type Epoxy resins, triglycidyl isocyanurate and the like can be mentioned. In order to accelerate the thermosetting reaction of these epoxy resins, a curing accelerator such as an imidazole, an amine compound, a carboxylic acid, a phenol, a quaternary ammonium salt, or a compound containing a methylol group can be used in combination. The content of the bifunctional or higher epoxy resin (D) is 5 to 60 per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B).
Preferably, the amount is 10 parts by weight, more preferably 10 to 40 parts by weight. Bifunctional or higher epoxy resin (D)
Is less than 5 parts by weight per 100 parts by weight of the total of the urethane acrylate having a carboxyl group (A) and the polybasic anhydride-modified epoxy acrylate resin (B), the adhesion and heat resistance of the cured coating film. May be reduced. When the content of the bifunctional or higher epoxy resin (D) exceeds 60 parts by weight per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B), There is a possibility that the dilute alkali developability and the flexibility of the cured coating film may decrease. In the present invention, a bifunctional epoxy resin (D)
Is preferably mixed immediately before applying the solder photoresist ink composition to the printed wiring board. By mixing the bifunctional epoxy resin (D) immediately before coating, it is possible to avoid the increase in the viscosity of the solder photoresist kinking composition and, consequently, the decrease in dilute alkali developability.

In the present invention, the diluent (E) includes:
Photopolymerizable monomers or organic solvents can be used.
As the photopolymerizable monomer, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n- propyl
(Meth) acrylate, n-butyl (meth) acrylate,
2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl
(Meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, benzyl (meth) ) Acrylate, ethylene glycol mono (meth) acrylate, ethyl carbitol
Monofunctional acrylate compounds such as (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (Meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth)
Examples include polyfunctional acrylates such as acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and polyfunctional epoxy acrylates. As an organic solvent that can be used as a diluent, for example, methyl ethyl ketone, ketones such as cyclohexanone, toluene, aromatic hydrocarbons such as xylene, methanol,
Alcohols such as isopropanol and cyclohexanol; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; petroleum solvents such as petroleum ether and petroleum naphtha; cellosolves such as cellosolve and butyl cellosolve; carbitol such as carbitol and butyl carbitol And acetates such as ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate and butyl carbitol acetate.

When the diluent is a photopolymerizable monomer, the photopolymerizable monomer has the effect of diluting the solder photoresist ink composition to have a viscosity that facilitates application and promotes photopolymerizability. Further, when the diluent is an organic solvent, the organic solvent has an effect of improving workability when diluting the solder photoresist ink composition, applying the diluted composition to a printed wiring board, and drying to form a film. In the present invention, the reaction diluent used in producing the urethane acrylate (A) having a carboxyl group or the polybasic anhydride-modified epoxy acrylate resin (B) can be the diluent (E). Further, if necessary, the diluent (E) is newly added to the reaction diluent present in the urethane acrylate (A) solution having a carboxyl group or the polybasic acid anhydride-modified epoxy acrylate resin (B) solution. Can be added. In the solder photoresist ink composition of the present invention, the diluent (E)
Is preferably 30 to 200 parts by weight per 100 parts by weight of the total of the urethane acrylate having a carboxyl group (A) and the polybasic acid anhydride-modified epoxy acrylate resin (B). When the content of the diluent (E) is less than 30 parts by weight per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B), the solder photoresist ink The viscosity of the composition may be too high, and the workability in the application step may be reduced. When the content of the diluent (E) exceeds 200 parts by weight per 100 parts by weight of the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B), one application There is a possibility that it may be difficult to form a coating film having a required thickness. In the solder photoresist ink composition of the present invention, if necessary, fillers such as barium sulfate and silicon oxide, phthalocyanine green, phthalocyanine blue, titanium dioxide, coloring pigments such as carbon black, defoaming agents, leveling agents And a polymerization inhibitor such as hydroquinone, hydroquinone monomethyl ether, pyrogallol, and t-butylcatechol.

The method for applying the solder photoresist ink composition of the present invention is not particularly limited. For example, the solder photoresist ink composition is applied to the entire surface of a printed wiring board by a screen printing method, a roll coater method, a spray method, a curtain coater method, etc.
After drying at 65 to 80 ° C. to remove tackiness (tack) on the surface, unnecessary portions are masked with a photomask or the like, and photo-curing can be performed. After light curing,
The unexposed part is developed by dissolving it using a dilute alkaline aqueous solution, and then thermally cured to form a solder photoresist ink film. The irradiation light source for photocuring is not particularly limited, and for example, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a metal halide lamp, and the like can be used. Since the urethane acrylate (A) has a carboxyl group in the molecule, the solder photoresist ink composition of the present invention has extremely good dilute alkali developability. In addition, since urethane acrylate (A) has a large number of urethane bonds in the molecule, the flexibility of the film obtained by curing is improved, and the number of ester bonds that are easily hydrolyzed is relatively reduced. The pressure cooker resistance, which indicates durability under high humidity, is improved. In particular, when dimethylolbutanoic acid or dimethylolpropionic acid is used as the compound (a) having two or more hydroxyl groups and one or more carboxyl groups, the ester bond is further reduced, and the resistance to pressure cooker is greatly increased. To improve. Further, by using the polybasic acid anhydride-modified epoxy acrylate resin (B) in combination, the heat resistance is improved, and a good performance can be obtained as a solder photoresist ink composition.

[0018]

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. In Examples and Comparative Examples, photocurability, developability and coating film performance were evaluated by the following methods. (1) Photocurable The solder photoresist ink composition was applied to the entire surface of the copper foil substrate in a film thickness of 10 to 15 μm by screen printing, and dried at 80 ° C. for 20 minutes in a hot air circulation type drying oven. The step step tablet is applied, and ultraviolet light of 500 mJ / cm ² is irradiated from a 3 kW metal halide lamp to perform photocuring. 2% aqueous solution of 1% sodium carbonate
After performing the diluted alkali development at 5 ° C., the evaluation is made based on the maximum number of steps in which the coating film completely remains. (2) Dilute alkali developability On a copper foil substrate, a solder photoresist ink composition is applied to the entire surface by a screen printing method in a film thickness of 10 to 15 μm, and dried at 80 ° C. for 20 minutes in a hot air circulation type drying furnace. UV light 500mJ / by 3kW metal halide lamp
Irradiate cm ² and perform photocuring. Next, the developability when developing with a 1% by weight aqueous sodium carbonate solution as a developing solution by stirring with a stirrer at 25 ° C. for 5 minutes is evaluated according to the following criteria. A: Developable within 1 minute. ○: Developable in more than 1 minute and within 3 minutes. Δ: Developable in more than 3 minutes and within 5 minutes. X: Development was impossible within 5 minutes. (3) Adhesion A copper photoresist substrate is coated with a solder photoresist ink composition in a thickness of 10 to 15 μm by a screen printing method, dried at 80 ° C. for 20 minutes in a hot air circulation type drying furnace, and then 3 kW metal halide. UV light 500mJ / by lamp
Irradiate cm ² and perform photocuring. Next, using a 1% by weight aqueous solution of sodium carbonate as a developing solution, development is performed at 25 ° C. for 5 minutes, and further thermosetting is performed at 150 ° C. for 30 minutes to prepare a test printed wiring board. JIS K540
0 In accordance with 8.5.2, cuts that penetrate the coating film on the printed wiring board for test and reach the surface of the substrate are made in a matrix of 11 rows and columns with a gap of 1 mm and adhered on the grid. The state of adhesion of the coating film after peeling off and peeling off the tape is visually observed. (4) Pencil hardness According to JIS K 5400 8.4.2, the coating film on the test printed wiring board was scratched five times with a pencil [Mitsubishi Pencil Co., Ltd., Mitsubishi Uni], and the density symbols were mutually different. For two adjacent pencils, a set of two or more scratches and less than two scratches is determined, and the concentration symbol of the pencils with less than two scratches is defined as the pencil hardness of the coating film. (5) Solder heat resistance A rosin-based flux [Asahi Chemical Laboratory Co., Ltd., GX-7] is applied to the test printed wiring board,
Float for 5 seconds in a solder bath maintained at a temperature of 5 ° C. so that the coating surface contacts the solder, and then observe the blistering and peeling of the coating. This is defined as one cycle, and the evaluation is made based on the total time until the coating film swells or peels off. (6) Resistance to pressure cooker The test printed wiring board was left in a closed container kept at 127 ° C., 2 atm, and 100% relative humidity for 24 hours.
The deterioration of the substrate surface is visually observed. A: There is no deterioration of the resist film surface. ：: Slight precipitates appear on the surface of the resist film. Δ: Precipitate clearly appears on the resist film surface. X: The resist film is discolored or damaged. (7) Flexibility A 100 μm-thick polyimide film was coated with a solder photoresist ink composition by screen printing.
The film is coated on the entire surface in a thickness of 0 to 15 μm, dried at 80 ° C. for 20 minutes in a hot air circulation type drying furnace, irradiated with ultraviolet rays of 500 mJ / cm ² by a 3 kW metal halide lamp, photo-cured, and further subjected to a hot air circulation type. 30 at 150 ° C using a drying oven
Perform heat splitting. The polyimide film substrate thus prepared is bent by 180 ^° so that the resist coating surface is outside, and damage such as cracks in the resist film is visually observed. A: There is no change in the resist film. ：: White streaks appear slightly on the resist film. Δ: Clear white streaks appear on the resist film. ×: Cracks are generated in the resist film.

Production Example 1 (Production of a urethane acrylate having a carboxyl group) In a 3-liter separable flask, 1,075.1 g of ethyl carbitol acetate, 786.0 g (3 mol) of dicyclohexylmethane diisocyanate and dimethylolbutanoic acid were added. 296.0 g (2 mol) were charged. Heat to 70 ° C with stirring in a nitrogen stream atmosphere.
The reaction was continued for 2 hours while maintaining the temperature. Once the reaction mixture was cooled to room temperature, 232.0 g (2 mol) of 2-hydroxyethyl acrylate was added, and after stopping the nitrogen flow, the mixture was heated to 80 ° C and reacted for 2 hours. The reaction product was cooled to room temperature. The acid value of this reaction product as a solution was 47 mgKOH / g, and the acid value as a resin was 85 mgKOH / g.
OH / g. The solid content of the reaction product is 55%.
% By weight. Hereinafter, this reaction product is used as a resin solution (A-
Abbreviated as 1). Production Example 2 (Production of a urethane acrylate having a carboxyl group) In a 3-liter separable flask, 1,222.0 g of ethyl carbitol acetate, 393.0 g (1.5 mol) of dicyclohexylmethane diisocyanate, and 375.0 g of diphenylmethane diisocyanate (1.5 mol), 266.4 g (1.8 mol) of dimethylolbutanoic acid
And 63.2 g (0.2 mol) of an adduct of bisphenol A with 2 mol of ethylene oxide. The mixture was heated to 60 ° C. while stirring under a nitrogen stream atmosphere, and the reaction was continued for 2 hours while maintaining the temperature at 60 ° C. Once the reaction mixture was cooled to room temperature, 396.0 g (2 mol) of cyclohexanedimethanol monoacrylate was added, and after stopping the nitrogen stream, the mixture was heated to 80 ° C. and reacted for 2 hours. The reaction product was cooled to room temperature. The acid value of this reaction product as a solution was 37 mgKOH / g, and the acid value as a resin was 68 mgKOH / g.
OH / g. The solid content of the reaction product is 55%.
% By weight. Hereinafter, this reaction product is used as a resin solution (A-
Abbreviated as 2). Production Example 3 (Production of urethane acrylate having a carboxyl group) In a 3-liter separable flask, 1136.7 g of ethyl carbitol acetate, 393.0 g (1.5 mol) of dicyclohexylmethane diisocyanate, 282.0 g of xylylene diisocyanate ( 1.5 mol), 266.4 g (1.8 mol) of dimethylolbutanoic acid, 47.4 g of a 2 mol adduct of bisphenol A with ethylene oxide
(0.15 mol) and 4.5 g of trimethylolpropane
(0.033 mol). The mixture was heated to 60 ° C. while stirring under a nitrogen stream atmosphere, and the reaction was continued for 2 hours while maintaining the temperature at 60 ° C. Once the reaction mixture was cooled to room temperature, cyclohexane dimethanol monoacrylate 39
6.0 g (2 mol) was added, and the nitrogen gas flow was stopped.
The mixture was heated to 0 ° C. and reacted for 2 hours. The reaction product was cooled to room temperature. The acid value of the reaction product as a solution is 4
0 mgKOH / g, and the acid value as a resin is 73 mgKOH / g.
Met. The solid content of the reaction product was 55% by weight.
It is. Hereinafter, this reaction product is abbreviated as resin solution (A-3). Production Example 4 (Production of a urethane acrylate having a carboxyl group) In a 3-liter separable flask, 1131.7 g of ethyl carbitol acetate, 710.4 g (3.2 mol) of isophorone diisocyanate, and 251.6 g of dimethylolbutanoic acid ( 1.7 mol) and 158.0 g (0.5 mol) of an adduct of bisphenol A with 2 mol of ethylene oxide. 80 with stirring under nitrogen atmosphere
C., and the reaction was continued for 2 hours while maintaining the temperature at 80.degree. Once the reaction mixture was cooled to room temperature, 260.0 g (2 mol) of 2-hydroxyethyl methacrylate was added, and after stopping the nitrogen stream, the mixture was heated to 80 ° C and reacted for 2 hours. The reaction product was cooled to room temperature. The acid value of the reaction product as a solution was 38 mg KOH / g, and the acid value as a resin was 69 mg KOH / g. The solid content of the reaction product is 55% by weight. Hereinafter, this reaction product is abbreviated as resin solution (A-4). Production Example 5 (Production of polybasic acid anhydride-modified epoxy acrylate resin) In a 2-liter separable flask, 379.7 g of ethyl carbitol acetate, o-cresol novolac type epoxy resin [Nippon Kayaku Co., Ltd., EOCN- 103
S, epoxy equivalent: 215, softening point: 83 ° C.] 430.0 g
And 144.0 g (2 mol) of acrylic acid. Heat to 120 ° C with stirring, and keep the temperature at 120 ° C for 1
The reaction was continued for 0 hours. Once the reaction mixture was cooled to room temperature, 40.0 g (0.4 mol) of succinic anhydride and 91.2 g (0.6 mol) of tetrahydrophthalic anhydride were added, and
The mixture was heated to ℃ and reacted for 4 hours. The reaction product was cooled to room temperature. The acid value of this reaction product as a solution is 52
mgKOH / g, and the acid value of the resin was 80 mgKOH / g. The solid content of the reaction product is 65% by weight. Hereinafter, this reaction product is abbreviated as resin solution (B-1).

Example 1 Resin solution (A-1) 53.0 g, Resin solution (B-1) 4
5.0 g, dipentaerythritol hexaacrylate 6.0 g, photopolymerization initiator [Ciba Geigy Co., Irgacure 907] 4.5 g, photosensitizer [Nippon Kayaku Co., Ltd., Kayacure DETX-S] 1.5 g , A curing accelerator [Shikoku Chemical Industry Co., Ltd., Cureazole 2MA-OK] 1.0 g and a defoaming agent [Nichika Chemical Co., Ltd., Formrex SOL-30]
1.0 g was kneaded with a roll mill to prepare a solder photoresist ink composition (1 liquid). Then, this 1
In 50.0 g of the liquid, a solution of o-cresol novolak type epoxy resin in ethyl carbitol (solid content: 65
% By weight) [Toto Kasei Co., Ltd., Epototh YDCN-702
S] to obtain a solder photoresist ink composition. This solder photoresist ink composition is applied to a copper printed wiring board, which has been patterned by etching in advance, by screen printing.
It was applied on the entire surface in a film thickness of 5 to 20 μm, and was temporarily dried at 80 ° C. for 30 minutes using a circulating hot air drying oven. A 21-step tablet for evaluation of photocurability is applied to the temporarily dried test substrate, and a UV light of 500 mJ /
After irradiation with cm ^2, the film was developed with a dilute alkali and the photocurability was evaluated. The maximum number of steps in which the coating film completely remained was 9 steps. A test mask was applied to the pre-dried test substrate in the same manner, irradiated with ultraviolet rays at 500 mJ / cm ² , and photo-cured. Then, a 1% by weight aqueous sodium carbonate solution was used as a developing solution, and a stirrer was used at 25 ° C. With stirring, development took place in 1.5 minutes. A copper photoresist substrate is coated with a solder photoresist ink composition by screen printing.
It was coated on the entire surface with a film thickness of １５15 μm, dried at 80 ° C. for 20 minutes in a hot air circulation type drying oven, and then irradiated with ultraviolet rays at 500 mJ / cm ² by a 3 kW metal halide lamp to perform photocuring. Next, using a 1% by weight aqueous solution of sodium carbonate as a developing solution, development was performed at 25 ° C. for 5 minutes, and further performed at 150 ° C.
For 30 minutes to prepare a test printed wiring board. Using this printed wiring board for test, the adhesion, pencil hardness, solder heat resistance and pressure cooker resistance were evaluated. Adhesion was 10 points, pencil hardness was 4H, and solder heat resistance was 20 seconds. Further, in the pressure cooker resistance test, no deterioration of the resist film surface was observed at all. After applying the solder photoresist ink composition to the entire surface of the polyimide film having a thickness of 100 μm in a thickness of 10 to 15 μm by a screen printing method, drying, light curing and heat curing,
The flexibility was evaluated. No change was observed in the bent part of the resist film. Example 2 o-Cresol novolak type epoxy resin in ethyl carbitol (solid content 65% by weight) as two liquids 10.
A solder photoresist ink composition was prepared and evaluated in the same manner as in Example 1 except that 6.5 g of triglycidyl isocyanurate [Nippon Ciba Geigy, Araldite PT810] was used instead of 0 g. Example 3 Instead of 53.0 g of the resin solution (A-1), the resin solution (A-1) was used.
-2) A solder photoresist ink composition was prepared and evaluated in the same manner as in Example 1 except that 53.0 g was used. Example 4 A resin solution (A-1) was used in place of 53.0 g of the resin solution (A-1).
-3) A solder photoresist ink composition was prepared and evaluated in the same manner as in Example 1 except that 53.0 g was used. Example 5 Instead of 53.0 g of the resin solution (A-1), the resin solution (A-1) was used.
-4) A solder photoresist ink composition was prepared and evaluated in the same manner as in Example 1 except that 53.0 g was used. Comparative Example 1 90.0 g of the resin solution (B-1), 6.0 g of dipentaerythritol hexaacrylate, a photopolymerization initiator [Ciba.
Geigy, Irgacure 907] 4.5 g, photosensitizer [Nippon Kayaku Co., Ltd., Kayacure DETX-S] 1.5 g,
Curing accelerator [Shikoku Chemical Industry Co., Ltd., Curesol 2MA-
OK] and 1.0 g of an antifoaming agent [Nichika Chemical Co., Ltd., Formrex SOL-30] were kneaded with a roll mill to prepare a solder photoresist ink composition (1 liquid). Then, 50.0 g of this one solution was added as two solutions to o
10.0 g of a cresol novolak-type epoxy resin in ethyl carbitol (solid content: 65% by weight) [Toto Kasei Co., Ltd., Epototo YDCN-702S] was mixed to obtain a solder photoresist ink composition. This solder photoresist ink composition was evaluated in the same manner as in Example 1. Table 1 shows the composition of Examples 1 to 5 and Comparative Example 1, and Table 2 shows the evaluation results.

[0021]

[Table 1]

[0022]

[Table 2]

As can be seen from Table 2, the solder photoresist ink compositions of Examples 1 to 5 containing urethane acrylate having a carboxyl group and a polybasic acid anhydride-modified epoxy acrylate resin were photocurable and diluted. The alkali developability is good, and the resulting coating film has good adhesion, pencil hardness and solder heat resistance, and is excellent in pressure cooker resistance and flexibility. On the other hand, the solder photoresist ink composition of Comparative Example 1 containing no urethane acrylate having a carboxyl group was
Light curability and dilute alkali developability are good, and the resulting coating film has good adhesion and pencil hardness, and is excellent in solder heat resistance, but has extremely poor pressure cooker resistance and flexibility. .

[0024]

The solder photoresist ink composition of the present invention has excellent flexibility of a cured film and remarkably excellent pressure cooker resistance, which is durability under high temperature and high humidity. Further, as compared with the conventional solder photoresist ink composition, it has a dilute alkali developability equal to or higher than that of the conventional solder photoresist ink composition, and has a practical level of solder heat resistance.

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁶ Identification code FI G03F 7/027 515 G03F 7/027 515 7/032 501 7/032 501 (56) References JP-A-6-206956 (JP, A) JP-A-9-5997 (JP, A) JP-A-7-248622 (JP, A) JP-A-8-292569 (JP, A) JP-A-7-247330 (JP, A) (58) Survey Field (Int.Cl. ⁶ , DB name) C08G 59/17 C08G 59/42 C08G 18/67 C08F 299/02-299/08 G03F 7/027 G03F 7/032-7/037

Claims (9)

(57) [Claims] 1. A compound (a) having two or more hydroxyl groups and one or more carboxyl groups, a polyfunctional isocyanate having a six-membered ring structure (b), and a (meth) acrylate having a hydroxyl group (meth) acrylate c) a urethane acrylate having a carboxyl group obtained by reacting (c), a polybasic acid anhydride-modified epoxy acrylate resin (B), a photopolymerization initiator (C), a difunctional or higher epoxy resin (D), and dilution A solder photoresist ink composition comprising an agent (E). 2. The solder photoresist ink composition according to claim 1, wherein the compound (a) having two or more hydroxyl groups and one or more carboxyl groups is dimethylolbutanoic acid or dimethylolpropionic acid. 3. The polyisocyanate (b) having a 6-membered ring structure and having two or more functional groups is diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, xylylene diisocyanate,
2. The solder photoresist ink according to claim 1, which is one or more compounds selected from the group consisting of hydrogenated xylylene diisocyanate, tolylene diisocyanate, polymeric diphenylmethane diisocyanate, naphthalene diisocyanate, tetramethyl xylylene diisocyanate, and norbornane diisocyanate. Composition. 4. A urethane acrylate having a carboxyl group (A) is a compound (a) having two or more hydroxyl groups and one or more carboxyl groups, a bifunctional or more functional polyisocyanate having a 6-membered ring structure (b) 2. The solder photoresist ink composition according to claim 1, which is obtained by reacting (meth) acrylate (c) having a hydroxyl group with polyol compound (d) having two or more hydroxyl groups. 5. The polybasic acid anhydride-modified epoxy acrylate resin (B) is obtained by reacting a novolak type epoxy resin with a radically polymerizable unsaturated monocarboxylic acid, and further reacting a dibasic acid anhydride. The solder photoresist ink composition according to claim 1, which is a resin having a radical polymerizable unsaturated acyl group and a carboxyl group. 6. The weight ratio of the urethane acrylate having a carboxyl group (A) to the polybasic anhydride-modified epoxy acrylate resin (B) is from 2: 8 to 8: 2.
The solder photoresist ink composition according to the above. 7. The content of the photopolymerization initiator (C) is 1 in total of the urethane acrylate having a carboxyl group (A) and the polybasic acid anhydride-modified epoxy acrylate resin (B).
2. The solder photoresist ink composition according to claim 1, wherein the amount is 0.2 to 20 parts by weight per 00 parts by weight. 8. The content of the bifunctional or higher functional epoxy resin (D) is 5 to 100 parts by weight based on the total amount of the urethane acrylate (A) having a carboxyl group and the polybasic anhydride-modified epoxy acrylate resin (B). The solder photoresist ink composition according to claim 1, wherein the amount is 60 parts by weight. 9. The diluent (E) is one or more compounds selected from a photopolymerizable monomer and an organic solvent,
The content is 30 to 200 per 100 parts by weight of the total amount of the urethane acrylate having a carboxyl group (A) and the polybasic acid anhydride-modified epoxy acrylate resin (B).
The solder photoresist ink composition according to claim 1, which is in parts by weight.