JPH07301918A - Resist ink composition and forming method of solder resist film - Google Patents

Abstract

PURPOSE:To provide a resist ink compsn. and a film forming method to form a solder resist film having excellent adhesion property and heat resistance without causing resolution defect, bleeding, or problems concerning to embedding property in circuits and precision for printing position due to stretching or shrinkage of a screen. CONSTITUTION:This compsn. consists of (A) UV-curing resin having 30-150 acidity obtd. by the reaction of satd. or unsatd. polybasic acid anhydride and the reaction product of epoxy compd. and unsatd. monocarboxylic acid, (B) UV-curing monomer having 100-300 acidity obtd. by the reaction of methacrylate having hydroxyl groups and satd. or unsatd. polybasic acid anhydride, (C) unifunctional UV-curing monomer, (D) epoxy resin, (E) hardening agent for epoxy resin, and (F) photopolymn. initiator. The compsn. is applied on a substrate on which a conductive circuit is formed, precured with UV rays to form a resist film, then selectively peeled from the conductive circuit, and hardened with UV rays or/and by heating, or without curing to form the solder resist coating film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist ink composition used for printed wiring boards and a method for forming a solder resist film using the resist ink composition.

[0002]

2. Description of the Related Art Conventionally, a screen printing method has been widely used as a method for forming a solder resist pattern for various consumer and industrial printed wiring boards. However, this method is inherently low in resolution and causes bleeding and circuits. There are problems such as embedding in the space and printing accuracy due to expansion and contraction of the screen, and it has become impossible to cope with the recent high density of printed wiring boards and surface mounting of components. In order to solve these problems, a method using a dry film solder resist and a method using a liquid photo solder resist have been developed, but in the case of the dry film solder resist method, accuracy and blurring are improved to some extent, The resolution is still insufficient, and there are many problems such as poor embedding between circuits and pads, leaving air bubbles, poor adhesion and heat resistance, and is not always satisfactory for use in high-density surface mount printed wiring boards. It is not possible. On the other hand, the liquid photo solder resist method is a construction method that has recently been attracting attention because of its good embedding property and many advantages in terms of performance such as adhesion and heat resistance, and many proposals have been made. For example, Japanese Examined Patent Publication No. 1-54390 discloses an acid value of 30 to 150 obtained by reacting a reaction product of a novolac type epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride. A resist ink composition capable of developing an active energy ray-curable resin having a photopolymerization initiator, a diluting agent, and an epoxy compound having two or more epoxy groups in one molecule into an alkaline aqueous solution, In JP-A-1-141904, a photosensitive prepolymer having at least two ethylenically unsaturated bonds in one molecule is difficult to be used as a photopolymerization initiator, a photopolymerizable vinyl monomer as a diluent and a diluent. A resist ink composition, etc., which is developable in an alkaline aqueous solution in which a fine particulate epoxy compound having two or more epoxy groups in one molecule of soluble is used in combination is described. There, but is this other number of proposals. However, not limited to those described in the above publications, conventionally proposed liquid photo solder resist methods, like dry film solder resists, have insufficient resolution and resist between adjacent pads. There is a problem that it is difficult to form a film. Further, since the alignment with the negative film is required, its accuracy is limited, and the resist ink adheres to the pads due to the positional deviation between the adjacent pads,
At present, the reality is that it cannot withstand the recent use of high-density surface mount printed wiring boards.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances. That is, the object of the present invention is to eliminate problems such as bleeding, embedding between circuits, and poor printing position accuracy due to screen expansion and contraction, which are problems in conventional screen printing methods, and problems with liquid photo solder resist and dry film solder resist. Ink composition for forming a solder resist film having excellent adhesiveness and heat resistance where poor resolution and poor positional alignment due to the effect of positioning accuracy with a negative film, and the resist ink composition thereof Another object of the present invention is to provide a method for forming a solder resist film using

[0004]

Means for Solving the Problems As a result of intensive investigations by the present inventors, it was obtained by reacting a reaction product of an epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride. An ultraviolet curable resin having an acid value of 30 to 150 has a specific monomer, that is, a hydroxyl group (meth)
Use of a resist ink composition in which a UV curable monomer having an acid value of 100 to 300 and a monofunctional UV curable monomer obtained by reacting an acrylic ester with a saturated or unsaturated polybasic acid anhydride are combined. Unlike conventional liquid photosolder resist, when applied to the entire surface or a partial area of the substrate on which a conductor circuit is formed and preliminarily cured by ultraviolet rays, the alkaline aqueous solution is removed, the resist film on the base material is removed. It was found that only the conductor circuit was peeled off and the above object was achieved, and the present invention was completed.

That is, one of the features of the present invention is that UV curable resin having an acid value of 30 to 150 obtained by reacting a reaction product of an epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride B. UV-curable monomer having an acid value of 100 to 300 obtained by reacting a (meth) acrylic acid ester having a hydroxyl group with a saturated or unsaturated polybasic acid anhydride C.I. Monofunctional UV-curable monomer D. Epoxy resin E. Epoxy resin curing agent F. A resist consisting of a resist ink composition consisting of a photopolymerization initiator, which has the property that when it is applied on a substrate on which a conductor circuit has been formed and precured, only the precured resist film on the conductor circuit is peeled off by an alkaline aqueous solution. In ink composition.

Another feature of the present invention is that the resist ink composition is applied to the entire surface or a partial area of a substrate on which a conductor circuit is formed, and then pre-cured by ultraviolet rays, and then on the conductor circuit. A method for forming a solder resist film, which comprises peeling a pre-cured resist film with an alkaline aqueous solution and then curing it with ultraviolet rays and / or heat, or forming a solder resist film without curing with ultraviolet rays and / or heat. is there.

The present invention will be described in detail below. Examples of the ultraviolet curable resin (A) include a reaction product of an epoxy compound and an unsaturated monocarboxylic acid as described below, a dibasic acid anhydride such as phthalic anhydride, or an aromatic polyvalent such as pyromellitic dianhydride. It was obtained by reacting with a carboxylic acid anhydride. The acid value of the resin (A) thus obtained is in the range of 30 to 150, preferably 4
0 to 120. Here, when the acid value is less than 30, the releasability is poor, and when it is more than 150, not only the pre-cured resist film on the conductor circuit but also the pre-cured resist film on the base material Is peeled off, which is not preferable.

Examples of the epoxy compound include Epicoat 828, Epicoat 1001, Epicoat 1004, and Epicoat 1007 manufactured by Yuka Shell; Epicron 840, Epicron 860, Epicron 1050, Epicron 4050 manufactured by Dainippon Ink and Chemicals; Epotote YD-manufactured by Tohto Kasei. 128, YD-011, YD-019; Dow
DER-332, DER-662 manufactured by Chemicals; bisphenol A such as GY-260 and 6071 manufactured by Ciba-Geigy
Epoxy resin; Eikako Shell made Epicoat 807; Dainippon Ink and Chemicals Inc. Epicron S-129, Epicron 830; Toto Kasei YDF-170, YDF-2001
Bis-Shenol F type epoxy resin such as ST; Toto Kasei ST
-1000, ST-5080, hydrogenated bisphenol A
Type Epoxy Resins; Yuka Shell Epicoat 152, Epicoat 154; Dainippon Ink and Chemicals Epicron N-
665, N-695, N-730, N-770; Tohto Kasei YDCN-701, YDCN-704, YDPN-
638, YDPN-602; DEN- manufactured by Dow Chemical
431, DEN-438; Ciba-Geigy EPN-1
138, ECN-1235, ECN-1280, ECN
-1299; Nippon Kayaku EOCN-102, EOCN-
104, EOCN-1020; ECN-2 manufactured by Asahi Kasei Corporation
65, ECN-299; ESM-140 manufactured by Sumitomo Chemical Co., Ltd.
2, novolac type epoxy resin such as EOCN-220HH; heterocyclic epoxy resin such as triglycidyl isocyanurate; brominated epoxy resin, biphenol type epoxy resin, bixylenol type epoxy resin; amino group-containing glycidyl ether type epoxy resin, fat Examples thereof include cyclic or polybutadiene-modified epoxy compounds.

On the other hand, as the unsaturated monocarboxylic acid, acrylic acid, methacrylic acid, crotonic acid, cinnamic acid and the like can be used.

The above-mentioned saturated and unsaturated polybasic acid anhydrides include maleic anhydride, chlorendic anhydride,
Succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride An aromatic polycarboxylic acid anhydride such as trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride; 5- (2,5-dioxotetrahydrofuryl)- A polyvalent carboxylic acid anhydride derivative such as 3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride can be used. Epoxy resins, unsaturated monocarboxylic acids, and polybasic acid anhydrides that can be preferably used as the ultraviolet curable resin (A) include novolac type epoxy resins, acrylic acid, and tetrahydrophthalic anhydride.

The UV-curable monomer (B) having an acid value of 100 to 300 is a UV-curable monomer obtained by reacting a (meth) acrylic acid ester having a hydroxyl group with a saturated or unsaturated polybasic acid anhydride. Examples include type monomers. For example, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2
-Acryloyloxypropylphthalic acid, 2-acryloyloxyethyl-2-hydroxyethylphthalic acid, 2
-Acryloyloxyethyl hexahydrophthalic acid and / or methacrylic acid esters corresponding to the above-mentioned acrylic acid esters, and the like, and these can be used alone or in combination of two or more, but 2-acryloyloxyethyl succinic acid Can be preferably used. A suitable range of the amount of the ultraviolet-curable monomer (B) having an acid value of 100 to 300 as described above is 50 to 300 parts by weight, preferably 100 to 300 parts by weight of the ultraviolet-curable resin (A). The proportion is 100 to 250 parts by weight. here,
The UV-curable monomer having an acid value of 100 to 300 is 5
If the amount is less than 0 parts by weight, peeling with an alkaline aqueous solution becomes poor, and if the amount is more than 300 parts by weight, peeling also occurs on the substrate, which is not preferable.

As the monofunctional UV-curable monomer (C), 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, phenoxyethyl acrylate, phenoxypolyethylene glycol acrylate,
Tetrahydrofurfuryl acrylate, cyclohexyl acrylate, N-vinylpyrrolidone, acryloylmorpholine, methoxytetraethylene glycol acrylate, methoxypolyethylene glycol acrylate,
N, N-dimethylacrylamide, N-methylolacrylamide, N, N-dimethylaminopropylacrylamide, N, N-dimethylaminoethyl acrylate,
Monofunctional (meth) acrylate monomers such as N, N-dimethylaminopropyl acrylate and methacrylates corresponding to the above acrylates can be mentioned, and these can be used alone or in combination of two or more.
Further, a polyfunctional monomer can be used as long as it is 30 parts by weight or more based on 100 parts by weight of the monofunctional monomer. A suitable range of the amount of the monofunctional ultraviolet-curable monomer (C) used is 10 to 200 parts by weight, preferably 30 to 1 part by weight with respect to 100 parts by weight of the ultraviolet-curable resin (A).
The ratio is 50 parts by weight. Here, when the amount of the UV-curable monomer is less than 10 parts by weight, the viscosity of the resist ink is high and the workability is poor. Further, the result is that the pre-cured resist film on the substrate is easily peeled off at the time of peeling. On the other hand, if the amount is more than 200 parts by weight, the pre-cured resist film on the conductor circuit cannot be peeled off.

As the epoxy resin (D), the above-mentioned epoxy compounds may be used alone or in combination of two or more. The preferred range of the amount used is the ultraviolet curable resin (A), the ultraviolet curable monomer (B) having an acid value of 100 to 300, and the monofunctional ultraviolet curable monomer (C).
5 to 100 parts by weight, preferably 10 to 60 parts by weight, based on 100 parts by weight of the total amount used. Here, if the amount of the epoxy resin is less than 5 parts by weight, sufficient characteristics cannot be obtained by heat curing. On the contrary, if the amount is more than 100 parts by weight, the pre-cured resist film on the conductor circuit cannot be peeled off. Also, epoxy resin (D)
May be mixed in advance with the UV-curable resin, the UV-curable monomer and the epoxy resin curing agent, but it is desirable to mix the two before use in order to avoid thickening of the resist.

The epoxy resin curing agent (E) is 2MZ, 2E4MZ, C ₁₁ Z, C ₁₇ Z, 2P manufactured by Shikoku Chemicals.
Z, 1B2MZ, 2MZ-CN, 2E4MZ-CN, C
₁₁ Z-CN, 2PZ-CN, 2PHZ-CN, 2MZ-
CNS, 2E4MZ-CNS, 2PZ-CNS, 2MZ
_{-AZINE, 2E4MZ-AZINE, C 11} Z-AZ
INE, 2MA-OK, 2PHZ, 2P4BHZ and other imidazole derivatives; acetoguanamine, benzoguanamine, 3,9-bis- [2- (3,5-diamino-2,
4,6-Triazaphenyl) ethyl] -2,4,8,1
Guanamines such as 0-tetraoxaspiro (5,5) undecane; diaminodiphenylmethane, m-phenylenediamine, diaminodiphenylsulfone, cyclohexylamine, 4,4'-diamino-3,3'-diethyldiphenylmethane, diethylenetriamine, tetraethylene Pentamine, N-aminoethylpiperazine, isophoronediamine, dicyandiamide, urea, urea derivative,
Melamine, polyamines such as polybasic acid hydrazide, organic acid salts and / or epoxy adducts thereof; amine complex of boron trifluoride; trimethylamine, N, N-dimethyloctylamine, triethanolamine, N, N-dimethylaniline , N-benzyldimethylamine, pyridine, N-methylpyrrolidone, N-methylmorpholine, hexa (N-methyl) melamine, 2,4,6-tris (dimethylaminophenol), N-cyclohexyldimethylamine, tetramethylguanidine, Tertiary amines such as m-aminophenol; polyvinylphenol, polyvinylphenol bromide, phenol novolac, alkylphenol, alkylphenol novolac and other polyphenols; tributylphosphine, triphenylphosphine, Organic phosphines such as lis-2-cyanoethylphosphine; phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid, itaconic acid, chlorendic acid, methylhexahydrophthalic acid, methyltetrahydrophthalic acid, trimellitate Known and commonly used curing agents such as acid, pyromellitic acid, and polybasic acid anhydrides such as benzophenonetetracarboxylic acid can be used, and these can be used alone or in combination of two or more kinds.

The preferred amount of the epoxy resin curing agent (E) used is 0.2 to 30 parts by weight, preferably 2 to 20 parts by weight, based on 100 parts by weight of the epoxy resin (D). Here, when the amount of the epoxy resin curing agent is less than 0.2 parts by weight, the epoxy resin is not sufficiently cured, resulting in poor properties such as heat resistance. On the other hand, if the amount is more than 30 parts by weight, the cured epoxy resin product becomes brittle, resulting in insufficient properties such as heat resistance.

As the photopolymerization initiator (F), benzoins such as benzoin, benzyl, benzoin methyl ether, benzone isopropyl ether and benzoin alkyl ethers; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2, 2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 2, Two
-Dimethoxy-1,2-diphenylethan-1-one,
Acetophenones such as N, N-dimethylaminoacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone and the like anthraquinones; 2,4-dimethyl Thioxanthone,
Thioxanthones such as 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone, methylbenzophenone, 4,4′-dichlorobenzophenone, 4, Examples thereof include benzophenones such as 4′-bisdiethylaminobenzophenone and Michler's ketone. These initiators and sensitizers can be used alone or in combination of two or more kinds.

The preferred range of the amount of the photopolymerization initiator (F) used is the ultraviolet curable resin (A), the ultraviolet curable monomer (B) having an acid value and the monofunctional ultraviolet curable monomer (C). 0.2 to 3 per 100 parts by weight of the total amount used
It is 0 part by weight, preferably 2 to 20 parts by weight. here,
When the amount of the photopolymerization initiator is less than 0.2 part by weight, the ultraviolet ray curable resin, the ultraviolet ray curable monomer having an acid value and the monofunctional ultraviolet ray curable monomer are not sufficiently cured by the ultraviolet rays. On the contrary, when the amount is more than 30 parts by weight, the crosslink density does not increase and the coating properties of the resist film deteriorate.

The resist ink composition of the present invention may further contain barium sulfate, barium titanate, silicon oxide, talc, clay, magnesium carbonate, if necessary.
Inorganic fillers such as calcium carbonate, aluminum oxide, aluminum hydroxide, mica powder, phthalocyanine blue,
Known colorants such as phthalocyanine green, iocin green, disazo yellow, Victoria blue, crystal violet, titanium oxide, carbon black, naphthalene black, etc., known hydroquinone, hydroquinone monomethyl ether, tert-butyl catechol, pyrogallol, phenothiazine, etc. A commonly used polymerization inhibitor, a known and commonly used thickener such as asbestos, orben, benton, montmorillonite, and a defoaming agent and / or a leveling agent such as a silicone type, a fluorine type or an acrylic polymer type can be used.

In the method for forming a solder resist of the present invention, the above resist ink composition is applied to the entire surface or a partial area of a substrate on which a conductor circuit is formed, for example, a pad portion of a flat package such as IC or LSI. After that, it is pre-cured by ultraviolet rays, and then the resist film pre-cured on the conductor circuit is peeled off with an alkaline aqueous solution and then cured by ultraviolet rays and / or heat, or without ultraviolet curing and / or heat curing. Then, the method is carried out by forming a solder resist film by a known means such as a screen printing method, a dry film solder resist method or a liquid photo solder resist method.

The exposure amount of ultraviolet rays for performing pre-curing is
^{300mJ / cm 2 ~3000mJ / cm 2} , preferably ^{1000mJ / cm 2 ~2000mJ / cm 2} . If the exposure dose is less than 300 mJ / cm ² ,
Due to insufficient curing, it becomes easy to peel off on the base material.
If it is more than 00 mJ / cm ² , peeling on the circuit is poor. The irradiation of the resist film after peeling with ultraviolet rays is advantageous in that the resist film softened during the peeling is hardened again. The exposure amount may be the same as that at the time of pre-curing. Heat curing of the resist film after peeling is necessary to cure the epoxy resin in the resist ink composition of the present invention,
By hardening by heating, sufficient resistance can be imparted to the resist film. The heating temperature and heating time for curing are 120 ° C. to 180 ° C. and 30 minutes to 90 minutes. 12
If the temperature is lower than 0 ° C., the characteristics of the resist film are not sufficient due to insufficient curing. On the contrary, when the temperature is higher than 180 ° C., the resist film becomes brittle. If the curing time is shorter than 30 minutes, the curing becomes insufficient, and conversely, if the curing time is longer than 90 minutes, the resist film becomes brittle.

As the base material, a glass epoxy base material, a glass polyimide base material, a paper epoxy base material, a paper phenol base material, a composite base material and the like can be used.

As the solder resist ink,
Any known heat-curable solder resist ink, UV-curable solder resist, liquid photo-solder resist ink, dry film solder resist, etc. may be used. For example, heat-curable solder resist ink (S-222 X16 Taiyo Ink Manufacturing), UV curable solder resist ink (UV
R-150G EX2 manufactured by Taiyo Ink), liquid photo solder resist ink (manufactured by PSR-4000H7 manufactured by Taiyo Ink), dry film solder resist and the like can be preferably used.

The coating on the substrate on which the conductor circuit is formed is
For example, it is carried out by a screen printing method, a roll coater method, a curtain coater method, a spray coater method or the like on a substrate on which a conductor circuit is formed. Preliminary curing of the coating film is performed by irradiating ultraviolet rays using a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, a metal halide lamp or the like as an irradiation light source. Further, peeling of the resist film on the conductor circuit is performed by diluting an alkaline aqueous solution having a pH of 11 or more, such as an amine aqueous solution and 0.5.
This can be carried out by swelling the resist film with an aqueous solution of sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate of ˜5 wt%, but it is preferable to use an aqueous solution of sodium carbonate and potassium carbonate. When an amine is used, there is a problem of toxicity, and peeling with sodium hydroxide or potassium hydroxide deteriorates the electric insulation of the resist film.

As described above, the resist ink composition according to the present invention is applied to the entire surface or a partial area of a substrate on which a conductor circuit is formed, for example, a pad portion of a flat package such as IC, LSI, etc. After pre-curing with
Only the coating film on the conductor circuit can be peeled off with an alkaline aqueous solution. Therefore, after peeling, it is possible to make a printed wiring board excellent in various properties such as heat resistance by ultraviolet curing and / or heat curing, or by forming a solder resist film without ultraviolet curing and / or heat curing. In particular, SM of surface mount printed wiring boards
It is effective as a method of leaving the resist film between the D pattern pads.

[0025]

EXAMPLES The present invention will be specifically described below with reference to examples. All “parts” are based on weight unless otherwise specified.

Example 1 Phenoxyethyl acrylate was added to a reaction product obtained by reacting 1 equivalent of DEN-438 (a novolak type epoxy resin manufactured by Dow Chemical) with 1 equivalent of acrylic acid. Was used as a solvent and reacted by a conventional method. The content of phenoxyethyl acrylate is 50% by weight. Hereinafter, this is referred to as resin (A-1).

Blending component (a) Resin (A) -1 20.0 parts 2-acryloyloxyethyl phthalic acid 18.0 parts Triethylene glycol diacrylate 3.0 parts 2,2-dimethoxy-1,2-diphenylethane -1-one 5.0 parts Barium sulfate 26.0 parts Silicon dioxide 5.0 parts Iosin Green 0.5 parts KS-66 (Shin-Etsu Chemical defoamer) 0.5 parts C₁₁Z (hardening agent manufactured by Shikoku Chemicals)2.0 copies  80.0 copies in total

[0028] Ingredients (b) Epikote 807 (Yuka Shell manufactured bisphenol F type epoxy resin) 20.0 parts Total 20.0 parts

After premixing the above-mentioned compounding component (a), 3
A resist composition was prepared by kneading with this roll mill. Next, after mixing the ink containing the compounding component (a) with the compounding component (b), the composition is applied to the entire surface of the substrate (glass epoxy base material) on which the copper conductor circuit is formed by the screen printing method, and the Toshiba conveyor is used. 10 by high pressure mercury lamp curing furnace
It was pre-cured at a dose of 00 mJ / cm ² . Then 1
Using a weight% sodium carbonate aqueous solution (50 ° C.) as a stripping solution,
A peel test was performed at a spray pressure of 3 kg / cm ² . The results are shown in Table 1.

Example 2 Component (a) Resin (A-1) 15.0 parts 2-acryloyloxyethyl phthalic acid 25.0 parts Phenoxyethyl acrylate 5.0 parts 2,4-Dimethylthioxanthone 4.0 parts Talc 15.0 parts of calcium carbonate 3.0 parts phthalocyanine Green 0.5 part TSA-750 (Toshiba silicone Co. antifoam) 0.5 parts 2PHZ (manufactured by Shikoku Chemicals epoxy curing agent) 2.0 parts total 70. Copy 0

[0031] Ingredients (b) EPICLON -695 (manufactured by Dainippon Ink and Chemicals 20.0 parts cresol novolac epoxy resin) of 2-hydroxyethyl acrylate 10.0 parts Total 30.0 parts The above ingredients (a) a After premixing, the mixture was kneaded with a ball mill to prepare a resist composition. Further, the blending component (b) was dissolved by stirring. Then, after mixing the components (a) and (b), they were applied in the same manner as in Example 1, pre-cured and a peeling test was conducted. The results are shown in Table 1.

Example 3 Maleic anhydride (0.67 equivalents) was added to a reaction product obtained by reacting 1 equivalent of Epicron N-665 (cresol novolac type epoxy resin manufactured by Dainippon Ink and Chemicals, Inc.) with 1 equivalent of acrylic acid. , Phenoxyethyl acrylate were used as a solvent and reacted by a conventional method. The content of phenoxyethyl acrylate is 50% by weight. Less than,
This is abbreviated as resin (A-2).

Component (a) Resin (A-2) 30.0 parts 2-methacryloyloxyethyl phthalic acid 10.0 parts 2-hydroxyethyl methacrylate 10.0 parts 2-methyl-1- [4- (methylthio ) Phenyl] -2-morpholino-propan-1-one 4.5 parts Silicon dioxide 18.0 parts Finely powdered silicon dioxide 4.0 parts Phthalocyanine blue 0.5 parts KF-96 (Shin-Etsu Chemical antifoaming agent) 1 2.0 parts dicyandiamide 2.0 parts total 80.0 parts

[0034] After blending component (b) triglycidyl isocyanurate and 10.0 parts of 2-hydroxyethyl methacrylate 10.0 parts Total 20.0 parts The above ingredients (a) a premixed, the same method as in Example 1 Kneaded in. Further, the compounding component (b) was premixed and then kneaded by a three-roll mill. Then, after mixing the components (a) and (b), coating and pre-curing were carried out in the same manner as in Example 1, and a peeling test was conducted. The results are shown in Table 1.

Example 4 Component (a) Resin (A-2) 20.0 parts 2-Acryloyloxyethyl phthalic acid 30.0 parts Trimethylolpropane triacrylate 1.0 parts Phenoxyethyl acrylate 6.0 parts Barium sulfate 17.0 parts of phthalocyanine green 0.5 parts of AC-300 (manufactured by Kyoeisha Yushi anti-foaming agent) 2.0 parts benzoguanamine 3.5 parts total 80.0 parts

[0036] Ingredients (b) ECN-299 (manufactured by Asahi Kasei cresol novolak type epoxy resin) 15.0 parts of triethylene glycol diacrylate 5.0 parts Total 20.0 parts The above mixture (a) were pre-mixed After that, kneading was performed in the same manner as in Example 1. Further, the blending component (b) was dissolved by stirring. Then, after mixing the components (a) and (b), coating and pre-curing were carried out in the same manner as in Example 1, and a peeling peeling test was conducted. The results are shown in Table 1.

Comparative Example 1 1 equivalent of DEN-438 (a novolac type epoxy resin manufactured by Dow Chemical) and 1 equivalent of acrylic acid were reacted by a conventional method using phenoxyethyl acrylate as a solvent. The content of phenoxyethyl acrylate is 50% by weight. Hereinafter, this is abbreviated as resin (B-1).

Resin (B-1) 30.0 parts 2-Hydroxyethyl acrylate 28.0 parts 1-Chloroanthraquinone 4.0 parts DEN-438 (Epoxy resin manufactured by Dow Chemical) 25.0 parts Talc 10.0 parts after the phthalocyanine green 0.5 parts BYK-057 (BYK manufactured antifoaming agent) 0.5 parts 2MZ-AZINE (manufactured by Shikoku Chemicals epoxy curing agent) 2.0 parts total 100.0 parts the above mixture was pre-mixed Then, kneading, coating and preliminary curing were carried out in the same manner as in Example 1 to carry out peeling. The results are shown in Table 1.

Comparative Example 2 Component (a) Resin (A-1) 40.0 parts 2-Hydroxyethyl acrylate 15.0 parts Benzyl diethyl ketal 2.5 parts Barium sulphate 25.0 parts Phthalocyanine green 0.5 parts KS-66 (Shin-Etsu Chemical defoamer) 1.0 part Dicyandiamide1.0 copy  85.0 copies in total

Ingredient (B) Trimethylolpropane triglycidyl ether 15.0 parts Total 15.0 parts The above ingredient (a) was premixed and then kneaded in the same manner as in Example 1. Next, after the components (a) and (b) were mixed, application and pre-curing were carried out in the same manner as in Example 1, and a peeling and peeling test was conducted. The results are shown in Table 1.

Comparative Example 3 Ingredient (a) Resin (A-1) 20.0 parts 2-Hydroxyethyl acrylate 40.0 parts 2,4-Dimethylthioxanthone 2.0 parts Talc 14.5 parts Phthalocyanine Green 0.1. 5 parts TSA-750 (Toshiba silicone Co. antifoam) 1.0 part 2PHZ (manufactured by Shikoku Chemicals epoxy curing agent) 2.0 parts total 80.0 parts

Epicoat 807 (bisphenol F type epoxy resin manufactured by Yuka Shell Co., Ltd.) 20.0 parts Total 20.0 parts The above-mentioned blending component (a) was premixed and then kneaded in the same manner as in Example 1. Then, after mixing the components (a) and (b), coating and pre-curing were carried out in the same manner as in Example 1, and a peeling test was conducted. The results are shown in Table 1.

Comparative Example 4 Component (a) Resin (A-1) 20.0 parts 2-Acryloyloxyethyl phthalic acid 40.0 parts 2,4-Dimethylthioxanthone 2.0 parts Talc 14.5 parts Phthalocyanine green 0.5 parts TSA-750 (Toshiba silicone Co. antifoam) 1.0 part 2PMZ (manufactured by Shikoku Chemicals epoxy curing agent) 2.0 parts total 80.0 parts

Epicoat 807 (bisphenol F type epoxy resin manufactured by Yuka Shell Co., Ltd.) 20.0 parts Total 20.0 parts The above compounding component (a) was premixed and then kneaded in the same manner as in Example 1. Next, after the components (a) and (b) were mixed, application and pre-curing were carried out in the same manner as in Example 1, and a peeling and peeling test was conducted. The results are shown in Table 1.

Comparative Example 5 Using the resist ink compositions described in Examples 1, 2 and 3 of Japanese Patent Publication No. 1-54390, coating and preliminary curing were carried out in the same manner as in Example 1 of the present invention. A peel test was performed. The results are shown in Table 1.

[0046]

[Table 1] The evaluation methods and evaluation criteria in Table 1 are as follows.

Peeling time The time required for the resist ink on the conductor circuit to peel off.
(Peeling time was tested with an upper limit of 20 minutes.)

Peelability on Circuit The peeled state of the resist ink on the conductor circuit was visually determined. ． ○: The resist ink on the conductor circuit is 100% peeled off. B: The resist ink on the conductor circuit is partly peeled off. ×: The resist ink on the conductor circuit is not peeled off at all.

Deterioration on Substrate The deterioration (peeling) state of the resist ink on the substrate was visually determined. ○: The resist ink on the substrate has not been peeled off at all. Δ: The resist ink on the substrate is partly peeled off. X: The resist ink on the substrate is almost peeled off.

Example 5 Each of the resist films obtained in Examples 1 to 4 was irradiated with ultraviolet rays at an irradiation dose of 1000 mJ / cm ² , leaving a soldering portion, and a thermosetting solder resist ink ( S-222 X16 manufactured by Taiyo Ink Co., Ltd.) was applied and cured at 150 ° C. for 30 minutes to produce a printed wiring board. The printed wiring boards obtained here were referred to as Examples 5-1, 5-2, 5-3 and 5-4, respectively.
These were tested for adhesion, solder heat resistance, acid resistance, alkali resistance and solvent resistance. The results are shown in Table 2.

Example 6 The resist film obtained in each of Examples 1 to 4 was irradiated with ultraviolet rays at a dose of 1000 mJ / cm ² and then heat-cured at 150 ° C. for 60 minutes to form a soldered portion. Remaining, UV curable solder resist ink (UVR-
150G EX2 manufactured by Taiyo Ink Mfg. Co., Ltd.
It was cured at 00 mJ / cm ² to produce a printed wiring board. The printed wiring boards obtained here were referred to as Examples 6-1, 6-2, 6-3 and 6-4, respectively. These were tested for adhesion, solder heat resistance, acid resistance, alkali resistance and solvent resistance. The results are shown in Table 2.

Example 7 The resist films obtained in Examples 1 to 4 were irradiated with ultraviolet rays at a dose of 1000 mJ / cm ² to develop a solder resist ink (PSR-4000 H7).
(Manufactured by Taiyo Ink Mfg. Co., Ltd.), leaving the soldering part
Exposure and development were carried out, followed by heating and curing at 150 ° C. for 60 minutes to prepare a printed wiring board. The printed wiring boards obtained here are Examples 7-1, 7-2, 7-3 and 7-4, respectively.
And These were tested for adhesion, solder heat resistance, acid resistance, alkali resistance and solvent resistance. The results are shown in Table 2.

[0053]

[Table 2]

In the resist films of Comparative Examples 1, 2, 3 and 5, the resist film on the conductor circuit is peeled off only partially or not at all, and in Comparative Example 4, the resist film is peeled off. However, since the deterioration of the base material was severe, it was not possible to carry out the tests for adhesion, solder heat resistance, acid resistance, alkali resistance and solvent resistance. The evaluation methods and evaluation criteria in Table 2 above are as follows.

Adhesion property: According to the test method of JIS D-0202, each test piece was cross-cut in a grid pattern, and then the state of peeling after the peeling test was visually judged with cellophane tape. ○: 100/100 with no change. Δ: 50/100 to 90/100. X ... 0/100 to 50/100.

Solder heat resistance: 260 test pieces were prepared in accordance with the test method of JIS C-6481.
Floating in a solder bath at a temperature of 10 ° C. for 10 seconds was defined as one cycle, and after three cycles of each, “blister” and adhesion of the coating film were comprehensively evaluated. ○: No change is observed. B: Less than 10% of the coating film peeled off. X: The coating film was completely peeled off.

Acid resistance: Each test piece was immersed in a 10% by volume sulfuric acid aqueous solution at 20 ° C. for 30 minutes, and the state and the adhesion were comprehensively evaluated. ○: No change is observed. Δ: Change is observed. X: The coating film swelled and fell off.

Alkali resistance ... The same evaluation as the acid resistance test was conducted except that the 10% by volume sulfuric acid aqueous solution was replaced with a 10% by weight aqueous sodium hydroxide solution.

Solvent resistance: 10% by volume of sulfuric acid aqueous solution
Test evaluation was conducted in the same manner as the acid resistance test except that 1,1-trichloroethane was used instead.

Insulation resistance: Using the comb-shaped test pattern B of IPC-B-25, according to the test method of IPC SM-840B, direct current under the conditions of a normal condition and a temperature cycle of 25 ° C. to 65 ° C. and a relative humidity of 90% RH. 100 V was applied, and the insulation resistance value after moisture absorption and electrolytic corrosion after 7 days was measured.

[0061]

As described above, the resist ink composition according to the present invention can be peeled off only on the conductor circuit after being pre-cured with ultraviolet rays, and on the substrate on which the conductor circuit is formed. Since it is not necessary to perform pattern printing as in the conventional screen printing method, problems such as blurring, embedding between circuits, and print position accuracy due to expansion and contraction of the screen are eliminated. In addition, the resolution defect between the adjacent pads, which is a problem in the dry film solder resist or the liquid photo solder resist, can be solved. In addition, the pre-cured resist film formed between the pads is substantially flush with the pads, which can prevent the occurrence of bridges during soldering. Since the board on which the resist film pre-cured as described above is formed can leave a soldering part relatively widely, the solder resist ink can be applied to the pad part, the land part, etc. by the conventional screen printing method. It becomes possible to easily apply the coating, leaving the attachment part.
Further, when forming a solder resist film with a dry film solder resist or a liquid photo solder resist, the problem of embedding between circuits and between pads is eliminated, and a pre-cured resist film can be easily formed between pads. It will be possible. Furthermore, by using the resist ink composition of the present invention and carrying out the method of the present invention, it is possible to form a solder resist film excellent in various properties such as heat resistance, electric insulation and chemical resistance on a printed wiring board. In particular, it is extremely effective as a method of forming a solder resist film between the pads of the SMD pattern of the surface mount printed wiring board.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C09D 11/10 PTV G03F 7/028 H05K 3/06 H 3/28 D (72) Inventor Kenji Sawazaki 388, Okura, Arashiyama-cho, Hiki-gun, Saitama Prefecture Taiyo Ink Manufacturing Co., Ltd. Arashiyama Plant

Claims (9)

[Claims] 1. A. UV curable resin having an acid value of 30 to 150 obtained by reacting a reaction product of an epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride B. UV-curable monomer having an acid value of 100 to 300 obtained by reacting a (meth) acrylic acid ester having a hydroxyl group with a saturated or unsaturated polybasic acid anhydride C.I. Monofunctional UV-curable monomer D. Epoxy resin E. Epoxy resin curing agent F. It consists of a resist ink composition consisting of a photopolymerization initiator, and when applied on a substrate on which a conductor circuit is formed and pre-cured by ultraviolet rays, it has the property that only the pre-cured resist film on the conductor circuit is peeled off by an alkaline aqueous solution. A resist ink composition having: 2. An ultraviolet-curable monomer having an acid value of 100 to 300 obtained by reacting the (meth) acrylic acid ester having a hydroxyl group with a saturated or unsaturated polybasic acid anhydride is used as the ultraviolet-curable resin. The resist ink composition according to claim 1, which is contained in a ratio of 50 to 300 parts by weight with respect to 100 parts by weight. 3. The monofunctional UV-curable monomer is added in an amount of 10 to 200 with respect to 100 parts by weight of the UV-curable resin.
The resist ink composition according to claim 1, wherein the resist ink composition is contained in a ratio of parts by weight. 4. A ratio of the epoxy resin of 5 to 100 parts by weight based on 100 parts by weight of the total amount of the ultraviolet curable resin, the ultraviolet curable monomer having an acid value of 100 to 300, and the monofunctional ultraviolet curable monomer used. The resist ink composition according to claim 1, which is contained in 5. The resist ink composition according to claim 1, wherein the epoxy resin curing agent is contained in a proportion of 0.2 to 30 parts by weight with respect to 100 parts by weight of the epoxy resin. 6. The photopolymerization initiator is used in an amount of 0.2 to 30 per 100 parts by weight of the total amount of the ultraviolet curable resin, the ultraviolet curable monomer having an acid value of 100 to 300 and the monofunctional ultraviolet curable monomer used. The resist ink composition according to claim 1, wherein the resist ink composition is contained in a ratio of parts by weight. 7. The resist ink composition according to claim 1 is applied to the entire surface or a partial area of a substrate on which a conductor circuit is formed, then precured by ultraviolet rays, and then precured on the conductor circuit. A method for forming a solder resist film, which comprises peeling the resist film with an alkaline aqueous solution and then curing the film with ultraviolet light and / or heat, or forming a solder resist film without curing with ultraviolet light and / or heat. 8. After peeling off only the pre-cured resist film on the conductor circuit with an alkaline aqueous solution, the pre-cured resist film remaining on the base material is further exposed to UV light.
The method for forming a solder resist film according to claim 7, wherein the method is carried out by irradiating 0 to 3000 mJ / cm ² and curing. 9. After peeling off only the pre-cured resist film on the conductor circuit with an alkaline aqueous solution, the pre-cured resist film remaining on the substrate is further treated with 120 to 180.
The method for forming a solder resist film according to claim 7, wherein the method is heat-cured at 5 ° C. for 5 to 90 minutes.