KR101128571B1 - Photocurable/Thermosetting Resin Composition, and Printed Circuit Board Using the Same - Google Patents

Abstract

Provides photocurable and thermosetting compositions for printed wiring boards with stable coating properties over time for screen printing, curtain coating, spray coating, roll coating, etc., and excellent in heat resistance, adhesion and electrical insulation, and printed wiring boards using the same do.

As a means for achieving this, (A) carboxyl group-containing resin which has one or more carboxyl groups in 1 molecule, (B) photoinitiator, (C) polyhydroxycarboxylic acid ester type additive, (D) diluent, (E) Provided are a photocurable and thermosetting resin composition comprising a filler and (F) an epoxy resin.

Photocurable thermosetting resin composition, printed wiring board, photopolymerization initiator, polyhydroxycarboxylic acid ester additive, diluent, filler, epoxy resin

Description

Photocurable thermosetting resin composition and printed wiring board using same {Photocurable / Thermosetting Resin Composition, and Printed Circuit Board Using the Same}

BRIEF DESCRIPTION OF THE DRAWINGS The graph which shows the IR spectrum of BYK-R606 which is a polyhydroxycarboxylic acid ester type additive used in Examples 1-3.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocurable and thermosetting resin composition useful for the manufacture of printed wiring boards, and more particularly, to a coating curability having excellent stability over time, and excellent in heat resistance, adhesion, and electrical properties. And it relates to a printed wiring board using the same.

BACKGROUND ART With the recent rapid progress of semiconductor components, electronic devices tend to be compact, light weight, high performance, and multifunctional, and accordingly, high density of printed wiring boards is in progress. As a soldering resist used for such a printed wiring board, a liquid developing solder resist is used which is pattern-exposed with ultraviolet rays, developed to form an image, and finally cured (main cured) by heat and light irradiation. In addition, in consideration of environmental problems, a liquid solder resist (for example, Patent Document 1) of an alkali developing type using a dilute alkaline aqueous solution as a developer has become a mainstream.

The liquid solder resist is coated on the printed wiring board by screen printing, curtain coating, spray coating, roll coating, or the like, and is subjected to temporary drying by evaporating an organic solvent in order to enable contact exposure. It develops, forms a pattern, thermosets, and the hardened coating film excellent in heat resistance, electrical insulation, etc. is obtained.

However, the liquid solder resist has a problem that the coating property on the printed wiring board changes over time. By such a coating change, a copper foil edge part may become thin, and peeling at the time of plating and soldering may be caused, or an appearance defect may be caused.

Generally, coating property is adjusted by mix | blending thixotropy-imparting agents (for example, patent document 2), such as inorganic fillers, such as a silica, barium sulfate, talc, ultrafine silica, organic bentonite, and waxes. However, the inorganic filler or ultra fine silica has a problem that the affinity with the organic solvent or resin increases with time, and the thixotropy (hereinafter abbreviated as thixotropic) is lowered. In addition, organic bentonite has a small change over time, but when used in a large amount, there is a problem of lowering the electrical insulation. Moreover, waxes also have a problem of containing harmful organic solvents such as xylene.

[Patent Document 1] Japanese Patent Application Laid-Open No. 1-1141904 (Scope of Claims)

[Patent Document 2] Japanese Unexamined Patent Publication No. 2003-96368 (Scope of Claim)

Therefore, the present invention is to solve the above problems in the prior art, the main object is to show a stable coating property over time with respect to the screen printing method, curtain coating method, spray coating method, roll coating method and the like, A photocurable and thermosetting composition for printed wiring boards excellent in adhesion and electrical insulation, and a printed wiring board using the same.

Another object of the present invention is to provide a photocurable thermosetting composition which reduces harmful substances that cause environmental pollution.

MEANS TO SOLVE THE PROBLEM The present inventors examined in depth in order to achieve the said objective, As a result, (A) carboxyl group-containing resin which has one or more carboxyl groups in 1 molecule, (B) photoinitiator, (D) diluent, (E) filler, and (F) The photocurable and thermosetting resin composition which mix | blended the polyhydroxycarboxylic acid ester type additive with the (C) polyhydroxycarboxylic acid ester type | system | group additive to the composition containing an epoxy resin with respect to the screen printing method, the curtain coating method, the spray coating method, the roll coating method, etc. over time. The present inventors have found that they exhibit stable coating properties and do not reduce heat resistance, adhesion, electrical insulation, and the like, and have completed the present invention.

In addition, the polyhydroxycarboxylic acid ester-based additive (C) was found not to use harmful organic solvents such as xylene.

In the basic aspect of the photocurable thermosetting resin composition of this invention, (A) carboxyl group-containing resin which has one or more carboxyl groups in 1 molecule, (B) photoinitiator, (C) polyhydroxycarboxylic acid ester type additive, (D A photocurable and thermosetting resin composition containing a diluent, (E) filler and (F) epoxy resin is provided. In a preferable embodiment, the composition is characterized in that the polyhydroxycarboxylic acid ester additive (C) is an additive which does not contain xylene (hereinafter abbreviated as xylene-free), and the photocurable thermosetting resin is also provided. A composition is provided wherein the composition further contains (G) non-halogen-based organic pigments.

Moreover, in another aspect, the printed wiring board is provided which has a soldering resist layer and / or resin insulation layer obtained by hardening | curing the said photocurable thermosetting resin composition by active energy ray irradiation and / or heating.

Hereinafter, each component of the photocurable thermosetting resin composition of this invention is demonstrated in detail.

First, as carboxyl group-containing resin (A) which contains 1 or more carboxyl group in the said 1 molecule, resin which has a carboxyl group, specifically, carboxyl group-containing photosensitive resin (A ') and ethylenic which have an ethylenically unsaturated double bond by itself Both carboxyl group-containing resins (A) which do not have an unsaturated double bond can be used and are not limited to particular ones. In particular, the resins listed below (any of oligomers and polymers) can be preferably used.

(1) a carboxyl group-containing resin obtained by copolymerization of a compound having an unsaturated carboxylic acid and an unsaturated double bond,

(2) a carboxyl group-containing photosensitive resin obtained by adding an ethylenically unsaturated group as a pendant to a copolymer of an unsaturated carboxylic acid and a compound having an unsaturated double bond (for example, by adding glycidyl methacrylate),

(3) Unsaturated monocarboxylic acid is reacted with a copolymer of a compound having an epoxy group and an unsaturated double bond and a compound having an unsaturated double bond in one molecule, and a saturated or unsaturated polybasic acid anhydride is reacted with the resulting secondary hydroxyl group. Obtained carboxyl group-containing photosensitive resin,

(4) a carboxyl group-containing photosensitive resin obtained by reacting a copolymer of an acid anhydride having an unsaturated double bond and a compound having an unsaturated double bond other than that with a compound having a hydroxyl group and an unsaturated double bond in one molecule,

(5) a carboxyl group-containing photosensitive resin obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid and reacting a saturated or unsaturated polybasic acid anhydride with the resulting hydroxyl group,

(6) a hydroxyl group and a carboxyl group-containing photosensitive resin obtained by reacting a saturated or unsaturated polybasic acid anhydride with a hydroxyl group-containing polymer, and then reacting the resulting carboxylic acid with a compound having an epoxy group and an unsaturated double bond in one molecule;

(7) Saturated or unsaturated polybasic acids in reaction products with polyfunctional epoxy compounds, unsaturated monocarboxylic acids, compounds having one or more alcoholic hydroxyl groups and one reactive group other than alcoholic hydroxyl groups reacting with the epoxy group in one molecule. Carboxyl group-containing photosensitive resin obtained by reacting anhydride, and

(8) obtained by reacting unsaturated monocarboxylic acid with a polyfunctional oxetane compound having two or more oxetane rings in one molecule, and reacting a saturated or unsaturated polybasic acid anhydride with a primary hydroxyl group in the obtained modified oxetane resin Carboxyl group-containing photosensitive resin

Etc. can be mentioned.

Among these, carboxyl group-containing photosensitive resin which has two or more photosensitive unsaturated double bonds in 1 molecule, especially the carboxyl group-containing photosensitive resin of said (5) is preferable.

Since the carboxyl group-containing resin (A) as described above has a large number of free carboxyl groups in the side chain of the main chain and the polymer, development with a rare alkali aqueous solution is possible.

Moreover, the acid value of the said carboxyl group-containing resin (A) is the range of 40-200 mgKOH / g, More preferably, it is the range of 45-120 mgKOH / g. If the acid value of the carboxyl group-containing resin is less than 40 mgKOH / g, alkali development becomes difficult, while if it exceeds 200 mgKOH / g, since the dissolution of the exposed portion by the developing solution proceeds, the line becomes thinner than necessary or, in some cases, the exposed portion. It is not preferable because it is difficult to draw a normal resist pattern by dissolving and peeling with a developer without distinction between the and unexposed portions.

The compounding quantity of such carboxyl group-containing resin (A) in all the compositions is 20-60 mass%, Preferably it is 30-50 mass%. When it is less than the said range, since coating film strength falls, for example, it is unpreferable. On the other hand, when it is higher than the said range, since viscosity becomes high, printability, etc. fall, it is unpreferable.

Examples of the photopolymerization initiator (B) used in the present invention include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether; Acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, etc. Acetophenones; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone- Aminoacetophenones such as 1; Anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, and 1-chloroanthraquinone; Thioxanthones such as 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, 2-chlorothioxanthone, and 2,4-diisopropyl thioxanthone; Ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; Benzophenones such as benzophenone; Or xanthones; (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphineoxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine Phosphine oxides such as oxides and ethyl-2,4,6-trimethylbenzoylphenylphosphinate; Various peroxides etc. are mentioned, The conventional photoinitiator known in this way can be used individually, or can be used in combination of 2 or more type. The compounding quantity of these photoinitiators (B) in all the compositions is 0.2-10 mass%, Preferably it is 0.5-5 mass%. When the said compounding quantity is less than 0.2% of the composition whole quantity, since photocurability falls and the pattern formation after exposure and image development becomes difficult, it is unpreferable. On the other hand, when it exceeds 10 mass%, it is not preferable because not only the thick film sclerosis | hardenability falls but also causes a cost increase by the light absorption of the radical photopolymerization initiator itself.

Tertiary, such as N, N- dimethylamino benzoic acid ethyl ester, N, N- dimethylamino benzoic acid isoamyl ester, pentyl-4- dimethylamino benzoate, triethylamine, and triethanolamine with the photoinitiator (B) mentioned above Photosensitizers, such as amines, can be used individually or in combination of 2 or more types.

In addition, a titanocene-based photopolymerization initiator such as Chiba C. Specialty Chemical Co., Ltd. monohydrate 784 which initiates radical polymerization in the visible region, a leuco dye, or the like can be used in combination as a curing aid.

The polyhydroxycarboxylic acid ester additive (C), which is a feature of the present invention, is synthesized by transesterification of dicarboxylic acid dialkyl esters such as dicarboxylic acid dimethyl ester and alkanolamines, specifically, The BYK-R606 by Big Chemie Japan Corporation is mentioned.

Such polyhydroxycarboxylic acid esters, unlike conventional polycarboxylic acid amide additives, have a hydroxyl group (eg absorption of about 3430 cm ⁻¹ in FIG. 1) and an ester bond (eg about 1740 cm in FIG. 1). ^-1 ), which is soluble in alcohols such as isobutanol, and does not require the use of harmful volatile organic compounds (VOCs) such as xylene. In addition, thixotropy with excellent stability over time can be imparted in a smaller amount (amount of about 1/5 to 1/3) than the conventional polycarboxylic acid amide. This is inferred that the polyhydroxycarboxylic acid ester of the present invention can give excellent thixotropy even in a small amount because the conventional polycarboxylic acid amide is waxy and is not uniformly dispersed. do.

In addition, these polyhydroxycarboxylic acid esters can be used not only as thixotropic imparting agents but also as matting agents (gloss removers) by controlling the blending amount, for example by blending at least about 0.2% by mass in the composition.

The compounding quantity of such polyhydroxycarboxylic acid ester type additive (C) in the whole composition is 0.01-1.00 mass%, Preferably it is 0.05-0.8 mass%. When the compounding quantity of polyhydroxycarboxylic acid ester type additive (C) is less than the said range, since sufficient thixotropy is not achieved, it is not preferable. On the other hand, if it is higher than the above range, it is not preferable because pinholes or scratches are generated.

In addition, when such polyhydroxycarboxylic acid ester-based additives are used in combination with hydrophilic silica, a mesh structure is formed to improve thixotropy and further increase the stability of the effect.

The diluent (D) used in the present invention is used to improve the workability by adjusting the viscosity of the composition, and to increase the crosslinking density or to improve the adhesion, and the like. Solvents can be used.

As said photopolymerizable monomer, Alkyl (meth) acrylates, such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; Mono or di (meth) acrylates of alkylene oxide derivatives such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol; Polyhydric alcohols such as hexanediol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, trishydroxyethylisocyanurate or polyhydric (meth) acryl products of ethylene oxide or propylene oxide adducts thereof Rates; (Meth) acrylates of ethylene oxide or propylene oxide adducts of phenols such as phenoxyethyl (meth) acrylate and polyethoxydi (meth) acrylate of bisphenol A; (Meth) acrylates of glycidyl ethers such as glycerin diglycidyl ether, trimethylolpropane triglycidyl ether and triglycidyl isocyanurate; And melamine (meth) acrylate etc. are mentioned.

These may be used alone or in combination of two or more thereof. From the viewpoint of liquid stability of the composition, (meth) acrylates containing a hydrophilic group are preferable, and from the viewpoint of photocurability, polyfunctional (meth) acryl Rate is preferred. The use range of these photopolymerization monomers in all the compositions is 20 mass% or less, Preferably it is 10 mass% or less. If it exceeds this, since the touch drying property deteriorates, it is unpreferable.

In addition, in this specification, (meth) acrylate is a general term for acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions.

As said organic solvent, Ketones, such as methyl ethyl ketone and cyclohexanone; Aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; Cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, tripropylene glycol monomethyl ether Glycol ethers such as these; Esters such as ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butylcarbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; Aliphatic hydrocarbons such as octane and decane; Known conventional organic solvents such as petroleum solvents such as petroleum ether, petroleum naphtha, solvent naphtha and the like can be used. These organic solvents can be used individually or in combination of 2 or more types.

The amount of the organic solvent used depends on the coating method or the boiling point of the organic solvent to be used, and is not particularly limited, but is generally 50% by mass, preferably 30% by mass or less, and more preferably 20% by mass in the total composition. It is as follows. When a high boiling point organic solvent is included in a large amount, it is not preferable because the touch drying property is decreased or sagging occurs after drying after coating.

As the filler (E) used in the present invention, known inorganic fillers or organic fillers may be used, and when used in combination with the polyhydroxycarboxylic acid ester additive (C), a mesh structure is formed to form a thixotropic It is preferable to use hydrophilic silica which has the effect of improving the stability of the effect.

In addition, hydrophilic silica is what grind | pulverized the general silica powder here, and is other than what hydrophobized the surface of particle | grains with the organic compound (hydrophobic silica).

As inorganic fillers other than hydrophilic silica, known conventional ones such as barium sulfate, talc, clay, hydrophobic silica, aluminum oxide, aluminum hydroxide, calcium carbonate, organic bentonite, mica powder and the like can be used. These have the effect of increasing the strength or hardness of the coating film and can be used as necessary.

Examples of the organic filler include polyethylene, polypropylene, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, polycarbonate, and various acrylates such as polymethyl methacrylate. Mead, polyamide, polyester, polyvinyl chloride, polyvinylidene chloride, polydivinylbenzene, fluorine resin, polyphenylene oxide, polyphenylene sulfide, polymethylpentene, urea resin, melamine resin, benzoguanamine resin, Polyacetal resin, furan resin, silicone resin, cured epoxy resin, and the like.

The compounding quantity of these fillers (E) in all the compositions is 40 mass% or less, Preferably it is the range of 5-30 mass%. If the blending ratio of the filler is higher than the above range, the coating film properties are lowered or it is difficult to achieve sufficient printability, which is not preferable. Such a filler (E) also has an effect of preventing an extremely thin coating film such as a copper foil end, and it is preferable to mix an appropriate amount of those having a particle size of 10 µm or less.

The epoxy resin (F) of this invention is well-known ordinary various epoxy resins, for example, bisphenol-A epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, brominated bisphenol A-type epoxy resin, hydrogenated bisphenol A-type Epoxy Resin, Non-phenol Epoxy Resin, Bixylenol Epoxy Resin, Phenol Novolak Epoxy Resin, Cresol Novolak Epoxy Resin, Brominated Phenol Novolak Epoxy Resin, Novolak Epoxy Resin of Bisphenol A, Trihydroxyphenyl Glycidyl ether compounds such as methane type epoxy resins, tetraphenylolethane type epoxy resins, naphthalene skeleton-containing phenol novolak type epoxy resins, and dicyclopentadiene skeleton-containing phenol novolak type epoxy resins; Glycidyl ester compounds such as terephthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, and dimer acid diglycidyl ester; Alicyclic epoxy resins such as EHPE-3150 manufactured by Daicel Chemical Co., Ltd .: heterocyclic epoxy resins such as triglycidyl isocyanurate; Glycol, such as N, N, N ', N'- tetraglycidylmethaxylenediamine, N, N, N', N'- tetraglycidylbisaminomethylcyclohexane, N, N- diglycidyl aniline Known conventional epoxy compounds such as cydylamines or copolymers of glycidyl (meth) acrylates with compounds having ethylenically unsaturated double bonds can be used. In terms of dryness and heat resistance, phenol furnaces Particular preference is given to volacic epoxy resins, cresol novolac epoxy resins, biphenolic or bixylenol type epoxy resins or mixtures thereof or triglycidyl isocyanurate. These epoxy resins (F) can be used individually or can be used in combination of 2 or more type.

These epoxy resins (F) are thermosetted with the said carboxyl group-containing resin (A), and improve heat resistance, adhesiveness, etc. The compounding quantity of these epoxy resins (F) is 0.8-2.0 equivalent, Preferably it is 1.0-1.8 equivalent, with respect to 1 equivalent of carboxyl groups of the said carboxyl group-containing resin (A). When the compounding quantity of an epoxy resin (F) is less than 0.8 equivalent of an epoxy group, an unreacted carboxyl group will remain, the hygroscopicity of a hardened film will become high, PCT resistance will fall easily, and solder heat resistance and electroless plating resistance will also fall easily. Moreover, when the compounding quantity of an epoxy resin (F) exceeds 2.0 equivalents of epoxy groups, the developability of a coating film or the electroless-plating resistance of a cured film worsens, and PCT resistance also falls.

Although the photocurable thermosetting resin composition of this invention can be colored with an inorganic pigment, an organic pigment, an organic dye, etc. as needed, since organic dye causes a sensitivity fall, it is preferable to use an inorganic pigment or an organic pigment. Do. Specifically, phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, etc. are mentioned. In addition, it is preferable to use a non-halogen organic pigment (G) in terms of environmental problems and the like.

The compounding quantity of these pigments in a composition is generally 5 mass% or less except titanium oxide. When it exceeds the said range, since photocurability falls, it is unpreferable. In addition, when titanium oxide is used, it is generally used in 15 mass% or less in a composition.

In addition, the photocurable thermosetting resin composition of this invention can add imidazole salt, a boron trifluoride complex, an organometallic salt, etc. as a latent curing catalyst. Further, compounds such as adenine, vinyltriazine, dicyandiamide, orthotolylbiguanide, melamine, or salts thereof may be added for the purpose of preventing the oxidation of copper, that is, the printed wiring board. The compounding ratio of these compounds in a composition is generally 5 mass% or less, and by adding these, the chemical resistance of a cured coating film and adhesiveness with copper foil improve.

Moreover, the photocurable thermosetting resin composition of this invention is known normally, such as hydroquinone, hydroquinone monomethyl ether, t-butyl catechol, a pyrogarol, phenothiazine, etc. as needed in the range which does not reduce a coating film characteristic. Known conventional additives such as thermal polymerization inhibitors, silicone-based, fluorine-based, anti-foaming agents such as silicone-based, and / or leveling agents, silane coupling agents such as imidazole-based, thiazole-based, and triazonyl-based compounds. have.

The photocurable thermosetting resin composition of this invention which has the above composition is diluted as needed, and it adjusts to the viscosity suitable for an application | coating method, and this is, for example, the screen-printing method, the curtain coating method, the spray coating method, It apply | coats by methods, such as a roll coating method, and can form a turk-free coating film by volatilizing and drying the organic solvent contained in a composition at the temperature of 60-100 degreeC, for example.

Subsequently, through a photomask in which a predetermined pattern is formed, it is selectively exposed to active energy rays, and the unexposed portion is developed with a dilute alkaline aqueous solution to form a resist pattern. Or after the final curing by irradiating an active energy ray or by final curing (main curing) only by heat curing, adhesion, hardness, solder heat resistance, chemical resistance, solvent resistance, electrical insulation, corrosion resistance, resolution, plating resistance, PCT resistance And a cured film (solder resist film) having excellent moisture resistance. In particular, by taking the step of irradiating the active energy ray after heat curing or by irradiating the active energy ray after heat curing, an unreacted photosensitive group reacts to obtain a cured coating having excellent corrosion resistance, plating resistance and hygroscopicity. have.

As aqueous alkali solution used for the said image development, aqueous alkali solution, such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines, can be used. Moreover, low pressure mercury lamp, medium pressure mercury lamp, high pressure mercury lamp, ultrahigh pressure mercury lamp, xenon lamp, metal halide lamp etc. are suitable as irradiation light source for photocuring. In addition, a laser beam etc. can also be used as an active energy line.

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited to the following Example. In addition, in the following, "part" means a "mass part" unless there is particular notice.

Synthetic example

215 parts of cresol novolak type epoxy resin N-680 (manufactured by Dainippon Ink and Chemicals Co., Ltd., epoxy equivalent = 215) are placed in a four-necked flask equipped with a stirrer and a reflux condenser, and 196 parts of propylene glycol monomethyl ether acetate are added and heated to dissolve. I was. Next, 0.46 parts of methylhydroquinone as a polymerization inhibitor and 1.38 parts of triphenylphosphine as a reaction catalyst were added. The mixture was heated to 95-105 占 폚, 72.0 parts (1.0 equiv) of acrylic acid was slowly added dropwise and reacted for about 32 hours to obtain a reaction product having an acid value of 0.9 mgKOH / g. The reaction product (hydroxyl: 1 equivalent) was cooled to 80-90 ° C., 76.0 parts (0.5 equivalents) of tetrahydrophthalic anhydride was added to react for about 8 hours and then taken out after cooling. The carboxyl group-containing resin (A) thus obtained was 65% nonvolatile matter and an acid value of 77 mgKOH / g of a solid. Hereinafter, the varnish will be referred to as A-1 varnish.

Using the carboxyl group-containing resin varnish (A-1 varnish) obtained in the above synthesis example, the compounding components shown in Table 1 were kneaded with three roll mills to obtain respective formulations of the photocurable thermosetting resin composition. Moreover, the compounding component shown in Table 2 was kneaded with three roll mills, and the hardening | curing agent of the said photocurable thermosetting resin composition was obtained.

In addition, the obtained photocurable thermosetting resin composition was propylene glycol monomethyl ether acetate, and it adjusted so that the viscosity might be about 200 dPa * s.

Example Formulations Comparative Example One 2 3 One 2 A-1 varnish 60.0 60.0 60.0 60.0 60.0 Irg-369 ^{* 1} 4.0 4.0 4.0 4.0 4.0 BYK-R606 ^{* 2} 0.04 0.14 0.3 - - BYK-405 ^{* 3} - - - - 0.5 BYK-354 ^{* 4} 4.0 4.0 4.0 4.0 4.0 DPHA ^{* 5} 4.0 4.0 4.0 4.0 4.0 PMA ^{* 6} 1.0 1.0 1.0 1.0 1.0 Nipper thread L-300 ^{* 7} 1.0 1.0 1.0 1.0 1.0 Imsil A-8 ^{* 8} 10.0 10.0 10.0 10.0 10.0 Barium sulfate 20.0 20.0 20.0 20.0 20.0 Copper Phthalocyanine 0.5 0.5 0.5 0.5 0.5 Disazo yellow 0.1 0.1 0.1 0.1 0.1 Dicyandiamide 0.1 0.1 0.1 0.1 0.1 Melamine 0.8 0.8 0.8 0.8 0.8

ratio
Go * 1: Photoinitiator, 2-benzyl-2- dimethylamino-1- (4-morpholinophenyl) -butan-1-one by Chiba Specialty Chemicals Co., Ltd.
* 2: The polyhydroxycarboxylic acid ester type additive made by Nippon Bick Chemical Co., Ltd.
* 3: Japan Big Chemistry Co., Ltd., polycarboxylic acid amide additive
* 4 made in Japan BIC Chemistry Co., Ltd., acrylic leveling antifoaming agent
* 5: Nippon Kayaku Pharmaceutical, dipentaerythritol hexaacrylate
* 6: propylene glycol monomethyl ether acetate
* 7: manufactured by Tosoh Silica Co., Ltd., hydrophilic ultrafine silica
* 8: Tatsumori Kogyo Co., crystalline silica

Hardener E-157CA75 ^{* 9} 5.0 Epicoat 828 ^{* 10} 35.0 TEPIC-H ^{* 11} 10.0 DPHA ^{* 5} 15.0 PMA ^{* 6} 15.0
ratio
Go * 9: Varnish which melt | dissolved epicoat 157S70 made in Japan Epoxy Resin company in carbitol acetate with 70% of solid content
* 10: Japan Epoxy Resin Co., Ltd., bisphenol A epoxy resin
* 11: Nissan Chemical Co., Ltd., triglycidyl isocyanurate of high melting point type
* 5: Nippon Gunpowder, dipenaryrititol hexaacrylate
* 6: propylene glycol monomethyl ether acetate

Performance evaluation:

(1) storage stability (viscosity, thixotropic)

Initial viscosity of the photocurable and thermosetting resin composition formulations of Examples 1 to 3 and Comparative Examples 1 and 2 described above, and viscosity over time when left for 1, 2, 3, 4, 7 days in a thermostat at 50 ° C. Was measured under the following conditions.

Viscometer: Cone plate type viscometer (Tokimek Corporation)

Measuring temperature: 25 ℃

Cone revolutions: 5 rpm / min and 50 rpm / min

T? I value (reference value of thixotropy) = (value of 5 rpm / min) / (value of 50 rpm / min)

(2) storage stability (coating property)

The photocurable thermosetting resin composition preparation and hardening | curing agent of said Example 1-3 and Comparative Examples 1 and 2 were mixed by 4: 1 by weight ratio, and each photocurable thermosetting resin composition was adjusted. In addition, the coating property change over time was investigated using the preparation which left for 1, 2, 3, 4, 7 days in 50 degreeC thermostat.

Each of the above compositions was coated on a circuit-formed copper foil substrate with a slit curtain coater so as to have a dry film thickness of about 20 μm, dried at room temperature for 10 minutes at a flat state, and then leaned on a dedicated rack, followed by hot air After drying for 15 minutes at 80 ° C. in a circulation drying furnace, the coating properties were evaluated as follows:

○: uniformly coated without sagging.

(Triangle | delta): A droop generate | occur | produces and the difference in the film thickness of an upper part and a lower part is seen.

X: Remarkable droop occurs and copper foil appears.

(3) sensitivity

Each photocurable thermosetting resin composition adjusted as described above was coated on a substrate with a slit curtain coater so as to have a dry film thickness of about 20 μm, dried at room temperature for 10 minutes, and then leaned on a dedicated rack. After drying at 80 ° C. for 15 minutes in a hot-air circulating drying furnace, the step tablet of contact No. 2 was brought into close contact and exposed to a total amount of accumulated light of 300 mJ / cm ² , followed by 1 wt% aqueous solution of Na ₂ CO _3. After developing for 1 minute at 0.2 MPa spray pressure using, the sensitivity was evaluated in the number of stages obtained from the step tablet.

(4) developing life

Each photocurable thermosetting resin composition adjusted as described above was coated on a circuit-formed copper foil substrate with a slit curtain coater so as to have a dry film thickness of about 20 μm, dried at room temperature for 10 minutes, and then placed in a dedicated rack. The board | substrate which stood leaning and changed the drying time by 5 minutes each in the 80 degreeC hot air circulation drying furnace was prepared. A negative film was applied to the substrate, and a solder resist pattern was exposed to develop for 1 minute at a spray pressure of 0.2 MPa using an aqueous solution of 1 wt% Na ₂ CO ₃ , and the developing life after the drying (the longest possible developing time) was dried. Investigated.

(5) surface condition

Each of the photocurable and thermosetting resin compositions adjusted as described above was coated on a circuit-formed copper foil substrate with a slit curtain coater so as to have a dry film thickness of about 20 μm, dried at room temperature for 10 minutes, and then hot air circulation Drying was carried out at 80 ° C. for 15 minutes in a formula drying furnace. The negative film was applied to the substrate, and the solder resist pattern was exposed to develop for 1 minute at a spray pressure of 0.2 MPa using an aqueous solution of 1 wt% Na ₂ CO ₃ , followed by heat at 150 ° C. for 60 minutes in a hot air circulation drying furnace. Hardened.

The surface state of the obtained cured coating film was visually evaluated.

(6) solder heat resistance

Each of the photocurable and thermosetting resin compositions adjusted as described above was coated on a circuit-formed copper foil substrate with a slit curtain coater so as to have a dry film thickness of about 20 μm, dried at room temperature for 10 minutes, and then hot air circulation Drying was carried out at 80 ° C. for 15 minutes in a formula drying furnace. The negative film was applied to the substrate, and the solder resist pattern was exposed to develop for 1 minute at a spray pressure of 0.2 MPa using an aqueous solution of 1 wt% Na ₂ CO ₃ , followed by heat at 150 ° C. for 60 minutes in a hot air circulation drying furnace. Hardened. The rosin-based flux was applied to the substrate, immersed in a solder bath previously heated to 260 ° C. for 30 seconds, and the flux was washed with propylene glycol monomethyl ether, and then visually evaluated for expansion, peeling and discoloration of the resist layer. did.

○; No change was noticed at all.

?; Very slightly changed.

×; There is swelling or peeling in the coating.

The evaluation results of the photocurable and thermosetting resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2 thus obtained are shown in Table 3 below:

Example Comparative example One 2 3 One 2

(1) viscosity
(T? I value) Initial value 204
(1.37) 210
(1.44) 204
(1.55) 204
(1.12) 201
(1.42) 50 ° C, 1 day 210
(1.36) 207
(1.42) 210
(1.53) 192
(1.06) 207
(1.40) 50 ° C, 2 days 204
(1.37) 201
(1.42) 207
(1.53) 186
(1.02) 201
(1.40) 50 ° C, 3 days 204
(1.35) 207
(1.39) 207
(1.51) 189
(1.02) 195
(1.39) 50 ℃, 4 days 198
(1.32) 207
(1.37) 201
(1.50) 189
(1.01) 195
(1.36) 50 ℃, 7 days 198
(1.28) 201
(1.33) 204
(1.45) 195
(1.01) 198
(1.29)

(2) coating property Early ○ ○ ○ △ ○ 50 ° C, 1 day ○ ○ ○ × ○ 50 ° C, 2 days ○ ○ ○ × ○ 50 ° C, 3 days ○ ○ ○ × ○ 50 ℃, 4 days △ ○ ○ × ○ 50 ℃, 7 days △ △ ○ × △ (3) Sensitivity (300 mJ / cm ² ) 6 steps 6 steps 6 steps 6 steps 6 steps (4) Developing life (80 degrees Celsius) 80 minutes 80 minutes 80 minutes 80 minutes 80 minutes (5) surface condition Gross Gross mat Gross Gross (6) solder heat resistance ○ ○ ○ ○ ○ Presence of xylene in the composition none none none none has exist

Thus, it can be seen that the example using BYK-R606, which is a polyhydroxycarboxylic acid ester additive, does not include xylene, has excellent viscosity and thixotropy over time, and shows little change in coating properties. In addition, thixotropy equivalent to Comparative Example 2 to which about 0.5% of BYK-405, which is a polycarboxylic acid amide additive generally used, can be obtained can be obtained in Example 2 having a compounding amount of about 1/3.

Moreover, it turns out that even if mix | blending BYK-R606 which is the said polyhydroxycarboxylic acid ester type additive does not reduce coating-film characteristics, such as a sensitivity, image development life, and solder heat resistance.

The photocurable and thermosetting compositions of the present invention exhibit stable coating properties over time with respect to screen printing, curtain coating, spray coating, roll coating, and the like, and have a coating film peeled off during plating or soldering in the manufacture of printed wiring boards. It is possible to prevent the production of defective products or defective external coating films, and to ink without containing a volatile organic compound (VOC), which is a harmful organic solvent that causes environmental pollution.

Moreover, since it shows the stable coating property with time, mass production of the photocurable thermosetting resin composition of this invention becomes possible, and cost reduction can be carried out. Moreover, it contributes to the fall of the defective rate at the time of manufacture of a printed wiring board, and can also reduce the price of a product.

Claims (6)

(A) carboxyl group-containing resin which has one or more carboxyl groups in 1 molecule, (B) photoinitiator, (C) polyhydroxycarboxylic acid ester type additive, (D) diluent, (E) filler, and (F) epoxy resin It contains a photocurable thermosetting resin composition. The photocurable thermosetting resin composition according to claim 1, wherein the polyhydroxycarboxylic acid ester additive (C) is an xylene-free additive. The photocurable thermosetting resin composition according to claim 1, wherein the content of the polyhydroxycarboxylic acid ester additive (C) in the composition is 0.01 to 1.00 mass%. The photocurable thermosetting resin composition according to claim 1, wherein the filler (E) is hydrophilic silica. The photocurable thermosetting resin composition according to claim 1, further comprising (G) a non-halogen organic pigment. It has a soldering resist layer, resin insulation layer, or both obtained by hardening the photocurable thermosetting resin composition of any one of Claims 1-5 by active energy ray irradiation, heating, or both. Printed wiring board.

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