JP2016024284A - Alkali-soluble resist ink composition having high emissivity, light reflectance, and heat resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist ink composition which suppresses discoloration such as yellowing due to heat and has high emissivity, high light reflectance, and excellent heat resistance.SOLUTION: The alkali solution-soluble resist ink composition contains: a photocurable resin obtained by reacting, with an organic polybasic acid anhydride, a reaction product of an unsaturated carboxylic acid and one or more compounds selected from a novolac epoxy resin, a heterocyclic epoxy resin, and a bisphenol A epoxy resin; a photopolymerization initiator; a diluent; a thermosetting resin comprising an acrylic copolymer; titanium oxide particles coated with aluminum oxide; and hydrated magnesium silicate particles (talc).SELECTED DRAWING: None

Description

  The present invention relates to an alkali solution-soluble resist ink composition, and more specifically, obtained by reacting a reaction product of a novolak type epoxy resin or the like with an unsaturated carboxylic acid with an organic polybasic acid anhydride. A photocurable resin, a photopolymerization initiator, a diluent, a thermosetting resin made of an acrylic copolymer, titanium oxide particles coated with aluminum oxide, and hydrous magnesium silicate particles (talc) In addition, the present invention relates to an alkaline solution-soluble resist ink composition having high emissivity, light reflectance, and excellent heat resistance.

  2. Description of the Related Art Conventionally, a technique for covering a circuit portion with a solder resist film in order to protect a conductor circuit in a printed wiring board on which electronic components are soldered is widely known. In recent years, since light emitting diode elements (LEDs) are used as backlights for liquid crystal displays of portable terminals, personal computers, televisions, etc., and as light sources for lighting fixtures, light emitting diode elements are directly applied to printed wiring boards. Has also increased.

  For this reason, printed wiring boards on which light-emitting diode elements are mounted, and reflective boards used for light-emitting diode elements, are required to have a function that ensures the brightness of the light source and does not reduce the amount of reflected light. The solder resist film formed on the Punt wiring board or the light-emitting diode element reflector is required to have a high reflectance. Further, since the light emitting diode element is also a heat source, the solder resist film formed on the light emitting diode element reflecting plate is also required to have excellent heat dissipation characteristics.

  However, in a general solder resist film, when exposed to light from a light source for a long time, deterioration such as yellowing due to light occurs, and the reflectance may decrease. Further, in the heating process when soldering the light-emitting diode element to the printed wiring board, it is exposed to a high temperature of 250 ° C. or more, so that there is a problem that deterioration such as yellowing due to heat occurs and the reflectance decreases. .

  For this reason, for example, as described in JP2011-164507A (Patent Document 1), a white filler such as titanium oxide is used, and the resin composition, equivalent weight, and acid value are specified. , A photosensitive resin in which coloring at the time of heating is prevented to reduce the light reflectance and improve the light resistance, or as described in JP 2010-181647 A (Patent Document 2), under specific conditions A photosensitive composition and a solder that suppresses discoloration such as yellowing when exposed to high temperatures by using a white filler whose processing liquid when heated and boiled in pure water exhibits a pH in a predetermined range. As described in the resist composition and JP2013-161052A (Patent Document 3), the light reflectance is obtained by forming a resist film having an excellent appearance by containing an organic phosphate. Low Suppressed, such a curable resin composition having excellent heat resistance have been developed.

  However, all of the resin compositions described in Patent Documents 1 to 3 suppress a decrease in reflectance by preventing discoloration due to heat and poor appearance of a resist film when a large amount of titanium oxide or the like is used. Therefore, there has been a problem that no consideration has been given to the improvement of the heat radiation characteristics for releasing the heat generated from the light emitting diode element.

  On the other hand, as a resin composition with improved heat dissipation characteristics, for example, as described in JP-A-6-167806 (Patent Document 4), the resin component has a specific volume resistance value and particle diameter. A solder resist ink composition in which the thermal conductivity of the resist thin film is improved by containing an inorganic filler such as aluminum nitride, silicon carbide, or beryllium oxide, or described in JP 2010-59222 A (Patent Document 5). As described above, there is known a solder resist ink composition in which the emissivity of a resist thin film is improved by containing an inorganic filler containing carbon black.

  However, the solder resist ink compositions described in Patent Documents 3 and 4 cannot obtain sufficient light reflectivity of the resist film by blending the inorganic filler, and the printed wiring board having the light emitting diode element There is a problem that it is not suitable as a resist film.

JP 2011-164507 A JP 2010-181647 A JP 2013-161052 A JP-A-6-167806 JP 2010-59222 A

  Accordingly, an object of the present invention is to provide a resist ink composition that can suppress discoloration such as yellowing due to heat, and has high emissivity, light reflectance, and excellent heat resistance.

  As a result of intensive studies on the alkali solution-soluble resist ink composition, the present inventors have found that titanium oxide coated with aluminum oxide on a photocurable resin, a photopolymerization initiator, a diluent, and a thermosetting resin. The resist ink composition containing particles and hydrous magnesium silicate particles (talc) can suppress discoloration such as yellowing due to heat, and has high emissivity, light reflectance and excellent heat resistance. As a result, the present invention has been completed.

  The alkali solution-soluble resist ink composition of the present invention is a reaction product of at least one compound selected from a novolak epoxy resin, a heterocyclic epoxy resin and a bisphenol A epoxy resin and an unsaturated carboxylic acid. Photocurable resin obtained by reacting with polybasic acid anhydride, photopolymerization initiator, diluent, thermosetting resin made of acrylic copolymer, and titanium oxide coated with aluminum oxide It contains particles and hydrous magnesium silicate particles (talc).

  The alkaline solution-soluble resist ink composition of the present invention is a printed wiring board having a light emitting diode element using, for example, a screen printing method, a roll coating method, a curtain coating method, a spray coating method, a spin coating method, a dip coating method, etc. It is applied with a film thickness of 10 to 100 μm, and the necessary part of the resist ink is cured by irradiating ultraviolet rays or the like, and the unexposed part is dissolved with an alkaline solution to obtain a film formed in a desired pattern be able to. Furthermore, the resist film formed in the desired pattern can be obtained by applying heat to the film to cure the resist ink.

  Moreover, the titanium oxide particle coat | covered with the aluminum oxide mix | blended with the resist ink composition of this invention raises the whiteness of the obtained resist film, and provides a high radiation rate and light reflectivity to a resist film. The hydrous magnesium silicate particles (talc) contribute to further increase the radiation rate and light reflectance of the resist film provided by blending the titanium oxide particles.

  The alkaline solution-soluble resist ink composition according to the present invention is a light-emitting diode that generates heat in particular, because it suppresses discoloration such as yellowing due to heat, and exhibits high emissivity, light reflectance, and excellent heat resistance. It is suitable as a resist ink composition for forming a solder resist film on a printed wiring board on which elements are mounted.

  Hereinafter, preferred embodiments of the present invention will be described using examples and comparative examples. The present invention is not limited to the examples shown below, and various modifications can be made without departing from the technical idea of the present invention.

  The alkali-soluble resist ink composition of the present invention comprises a reaction product of at least one compound selected from a novolak type epoxy resin, a heterocyclic epoxy resin and a bisphenol A type epoxy resin with an unsaturated carboxylic acid. Photocurable resin obtained by reacting with basic acid anhydride, photopolymerization initiator, diluent, thermosetting resin comprising acrylic copolymer, and titanium oxide particles coated with aluminum oxide And hydrous magnesium silicate particles (talc).

1. Photocurable resin The photocurable resin used in the alkali-soluble resist ink composition of the present invention is composed of at least one compound selected from a novolac type epoxy resin, a heterocyclic epoxy resin, and a bisphenol A type epoxy resin. It is not particularly limited as long as it can be obtained by reacting a reaction product with an unsaturated carboxylic acid with an organic polybasic acid anhydride, but it can be obtained by reacting a novolak epoxy resin with an unsaturated monocarboxylic acid. The product obtained is preferably obtained by reacting an organic polybasic acid anhydride.

(1) Epoxy compound Any epoxy compound can be used as long as it is a bifunctional or higher polyfunctional epoxy resin, and the epoxy equivalent is not particularly limited, but 1000 or less is preferable, and 100 to 500 is particularly preferable. Examples of the multifunctional epoxy resin include phenol novolac type epoxy resins (Mitsubishi Chemical Co., Ltd .: jER152, jER154, Nippon Steel & Sumikin Chemical Co., Ltd .: YDCN-638), cresol novolac type epoxy resin (Nippon Steel & Sumikin Chemical Co., Ltd .: YDCN-700). -2, YDCN-700-3, YDCN-700-5, YDCN-700-7, YDCN-700-10, YDCN-704, YDCN-704A) and other novolak type epoxy resins, bisphenol A type epoxy resins (Mitsubishi Chemical) Company: jER828, jER1001, jER1002, jER1003, jER1004, jER1005) and other phenol type epoxy resins, heterocyclic epoxy resins, and the like. These may be used alone or in combination.

(2) Unsaturated carboxylic acid Unsaturated carboxylic acid is a carboxylic acid-containing substance having an unsaturated bond active in an energy ray, such as acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, etc. as representative examples. 1 type, or 2 or more types of these can be used.

  The (meth) acrylate compound obtained by the reaction between the epoxy compound and the unsaturated carboxylic acid may be one obtained by reacting acrylic acid alone, or may be one obtained by reacting methacrylic acid alone. Alternatively, it may be obtained by reacting both acrylic acid and methacrylic acid.

  The use ratio of the epoxy compound and acrylic acid and / or methacrylic acid is acrylic acid and / or methacrylic acid (total of both companies when both acrylic acid and methacrylic acid are used) from the viewpoint of reacting all epoxy groups. Must be used in an amount of 1 equivalent or more.

  In addition, from the viewpoint of maintaining the storage stability of the (meth) acrylate compound to be produced and preventing excess acrylic acid from remaining, acrylic acid and / or methacrylic acid is 1. It is preferably used in an amount of 0 to 1.5 equivalents.

(3) Reaction solvent The reaction between the epoxy compound and acrylic acid and / or methacrylic acid may be carried out without using a solvent, but is preferably carried out in an inert organic solvent from the viewpoint of carrying out the reaction smoothly. . Examples of the organic solvent that can be used in this case include hydrocarbon solvents such as n-hexane, benzene, toluene, and xylene; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; esters such as ethyl acetate and butyl acetate. Examples of the solvent include ether solvents such as diethyl ether and tetrahydrofuran; halogen solvents such as dichloromethane, chloroform, carbon tetrachloride, and 1,2-dichloroethane. One or more of these may be used. it can.

(4) Catalyst The reaction of a part of the epoxy group of the epoxy compound with acrylic acid and / or methacrylic acid may be carried out without using a catalyst. However, since the reaction rate can be increased, the reaction is carried out with an acid addition catalyst. It is preferable.

  As the acid addition reaction catalyst, a quaternary onium salt, a tertiary amine and a tertiary phosphine are preferable, and one or more of these can be used.

  Specific examples of the quaternary onium salt include tetrabutylammonium bromide, triethylbenzylammonium chloride, tetrabutylphosphonium bromide, tetraphenylphosphonium bromide and the like.

  Specific examples of the tertiary amine include trialkylamines such as triethylamine and tributylamine; dialkylarylamines such as dimethylbenzylamine and diethylbenzylamine; triethanolamine and the like.

  Specific examples of the tertiary phosphine include triarylphosphine such as triphenylphosphine, tribenzylphosphine, and tritolylphosphine; tricycloalkylphosphine such as tricyclohexylphosphine; triethylphosphine, tripropylphosphine, tributylphosphine, trioctylphosphine, and the like And trialkylphosphine.

  Said acid addition reaction catalyst may be used independently or may use 2 or more types together. Among them, as the acid addition catalyst, triphenylphosphine is preferably used from the viewpoint that reaction activity and halogen are avoided.

  When the reaction between an epoxy group and acrylic acid and / or methacrylic acid is carried out using an acid addition reaction catalyst, the amount of the acid addition catalyst used is acrylic acid and / or methacrylic acid (both acrylic acid and methacrylic acid). Is used, it is preferably 0.0001 to 1.0 mol, more preferably 0.001 to 0.1 mol, based on 1 mol.

(5) Polymerization inhibitor In addition, in the reaction of acrylic acid and / or methacrylic acid with an epoxy compound, a polymerization inhibitor may or may not be added. Polymerization of the resulting epoxy group-containing (meth) acrylate compound can be prevented.

  The polymerization inhibitor used in the reaction is not particularly limited, and examples thereof include hydroquinone, p-methoxyphenol, p-zenzoquinone, phenothiazine, and dibutylhydroxytoluene. Only one type of polymerization inhibitor may be used, or two or more types may be used in combination.

  When adding a polymerization inhibitor, 0.0005 to 0.005 mol of the polymerization inhibitor is used per 1 mol of acrylic acid and / or methacrylic acid (a total of both when acrylic acid and methacrylic acid are used). Is preferably added at a rate of 0.001 to 0.005 mol.

  The reaction method of the epoxy compound and the radically polymerizable unsaturated monocarboxylic acid such as acrylic acid and / or methacrylic acid is not particularly limited. For example, the epoxy compound and acrylic acid and / or methacrylic acid are heated in a suitable reaction solvent. It can be made to react by doing. Moreover, as temperature at the time of making acrylic acid and / or methacrylic acid react with an epoxy compound, it is 50-150 degreeC from viewpoints of acceleration | stimulation of reaction, the production | generation suppression of a by-product, etc., and 80-120 degreeC is more preferable. The reaction time is usually preferably 4 to 20 hours, and more preferably 6 to 12 hours.

(6) Organic polybasic acid anhydride An organic polybasic acid anhydride reacts with a hydroxyl group produced by a reaction between an epoxy compound and a radically polymerizable unsaturated monocarboxylic acid such as acrylic acid and / or methacrylic acid, and a resin. Has a free carboxyl group. The organic polybasic acid anhydride to be used is not particularly limited, and either saturated or unsaturated can be used. Examples of organic polybasic acid anhydrides include saturated polybasic acid anhydrides and unsaturated polybasic acid anhydrides, such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methyltetrahydrophthalic anhydride. Examples thereof include acid, methylhexahydrophthalic anhydride, maleic anhydride, succinic anhydride, itaconic anhydride and the like, and one or more of these can be used.

2. Photopolymerization initiator As the photopolymerization initiator used in the alkali-soluble resist ink composition of the present invention, known ones can be used, for example, benzoin, benzoin ethyl ether, benzophenone, acetophenone, etc. Can do. These photopolymerization initiators may be used as a powder or as a solution. Examples of the solvent include ethyl acetate, methyl acetate, methyl ethyl ketone and the like.

3. Diluent Examples of the diluent used in the alkali-soluble resist ink composition of the present invention include ester solvents such as propylene glycol monomethyl ether acetate, alcohol solvents such as propylene glycol monomethyl ether, and aromatic solvents such as toluene. Can be used.

4). Thermosetting resin made of acrylic copolymer The thermosetting resin made of an acrylic copolymer used in the alkali-soluble resist ink composition of the present invention has a (meth) acrylate monomer and a carboxyl group (meta ) It can be obtained by copolymerizing with an acrylate monomer. The thermosetting resin is preferably contained in an amount of 35 to 600 parts by weight with respect to 100 parts by weight of the photocurable resin in order to suppress discoloration such as yellowing due to heat of the obtained resist film.

(1) (Meth) acrylate monomers (Meth) acrylate monomers that can be used in the present invention include benzyl methacrylate, benzyl acrylate, cyclohexyl acrylate, cyclohexyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, phenoxypolyethylene glycol acrylate, and phenoxypolyethylene glycol methacrylate. Styrene, nonylphenoxypolyethylene glycol monoacrylate, nonylphenoxypolyethyleneglycol monomethacrylate, nonylphenoxypolypropylenemonoacrylate, nonylphenoxypolypropylenemonomethacrylate, 2-hydroxy-3-phenoxypropylacrylate, 2-acryloyloxyethylphthalate, 2-actyl Leuoxyethyl-2-hydroxyethyl phthalate, 2-methacryloyloxyethyl-2-hydroxypropyl phthalate, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, i-propyl acrylate, i-propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, i-butyl acrylate, i-butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, 2-hydroxyethyl acrylate , 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate 3-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 3-ethylhexyl acrylate, ethylene Examples thereof include glycol monoacrylate, ethylene glycol monomethacrylate, glycerol acrylate, glycerol methacrylate, glycerol monoacrylate, glycerol monomethacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, and the like. In addition, you may use a methacrylate type copolymer individually or in mixture of 2 or more types as needed.

(2) (Meth) acrylate monomer having a carboxyl group Examples of (meth) acrylate monomers having a carboxyl group that can be used in the present invention include acrylic acid, methacrylic acid, acrylic acid dimer, crotonic acid, cinnamic acid, and maleic acid. , Maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, reaction products of polybasic acids and hydroxyalkyl (meth) acrylates, and the like.

(3) Polymerization initiator The polymerization initiator that can be used in the present invention includes 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis- (4-methoxy-2,4-dimethylvalero). Nitrile azo compounds (nitrile azo polymerization initiators) such as nitrile); dimethyl 2,2′-azobis (2-methylpropionate), 2,2′-azobis (2,4,4-trimethylpentane) Non-nitrile azo compounds (non-nitrile azo polymerization initiators) such as t-hexyl peroxypivalate, tert-butyl peroxypivalate, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, Stearoyl peroxide, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, succinic pe Peroxide, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, Examples include 4-methylbenzoyl peroxide, benzoyl peroxide, organic peroxides (peroxide-based polymerization initiator) such as 1,1′-bis- (tert-butylperoxy) cyclohexane, hydrogen peroxide, and the like.

(4) Solvent Solvents that can be used in the present invention include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, carbitol, methylcarbitol, butylcarbi Toluene, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monoethyl ether and other glycol ethers; ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butylcarby Acetic esters such as tall acetate, propylene glycol monomethyl ether acetate; ethanol, propanol, ethylene Examples include alcohols such as glycol and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. These may be used alone or in combination of two or more. They can be used in combination. In addition, after polymerization, monobasic, dibasic, and polybasic acids may be reacted, whereby developability can be improved.

5. Titanium oxide particles coated with aluminum oxide Titanium oxide particles used in the alkali-soluble resist ink composition of the present invention may be those by sulfuric acid method, chlorine method, rutile as long as they are coated with aluminum oxide. Type and anatase type titanium oxide particles can be used. These titanium oxide particles coated with aluminum oxide have excellent dispersibility and storage stability in the resist ink composition, increase the whiteness of the resulting resist film, and provide high emissivity and light reflection to the resist film. Give rate.

  The titanium oxide particles coated with aluminum oxide preferably have an average primary particle size of 0.20 μm or more and 0.30 μm or less, based on 100 parts by weight of the total of the photocurable resin and the thermosetting resin. It is preferable that 50-70 weight part is mix | blended. When the average primary particle diameter of the titanium oxide particles coated with aluminum oxide is less than 0.20 μm or the compounding amount with respect to 100 parts by weight of the resin component is larger than 70 parts by weight, the titanium oxide particles coated with aluminum oxide cause aggregation or the like. Thus, dispersibility in the resist ink composition is lowered. On the other hand, when the blending amount with respect to 100 parts by weight of the resin component is less than 50 parts by weight or the average primary particle diameter is larger than 0.30 μm, the whiteness of the resist film is lowered, and sufficient radiation rate and light reflectance are imparted to the resist film. Can not do.

  The titanium oxide particles coated with aluminum oxide are more preferably rutile type titanium oxide particles. Rutile-type titanium oxide particles are slightly inferior in whiteness compared to anatase-type titanium oxide particles, but the photocatalytic activity can effectively prevent deterioration and discoloration of the resulting resist film due to photoactivity.

  As rutile type titanium oxide coated with aluminum oxide, known rutile type can be used, and specifically, R-550, R-580, R-630, R-820, CR manufactured by Ishihara Sangyo Co., Ltd. -50, CR-60, CR-90, CR-97, TR-600, TR-700, TR-750, TR-840 manufactured by Fuji Titanium Industry Co., Ltd., KR-270, KR-310, KR- manufactured by Titanium Industry Co., Ltd. 380, Sakai Chemical Industry R-650, Dupont R-900, and the like.

6). Hydrous magnesium silicate particles (talc)
The hydrous magnesium silicate particles (talc) used in the alkali-soluble resist ink composition of the present invention are not particularly limited. For example, LMS-100, LMS-200 manufactured by Fuji Titanium Industry Co., Ltd., P manufactured by Nippon Talc Co., Ltd. -3, MSG, etc. can be used. The hydrous magnesium silicate particles (talc) contribute to further increase the radiation rate and light reflectance of the resist film provided by blending the titanium oxide particles.

In order to maximize the above effect, the hydrous magnesium silicate particles are preferably contained in an amount of 5 to 10 parts by weight with respect to 100 parts by weight of the titanium oxide particles, and the average primary particles of the hydrous magnesium silicate particles. The diameter is preferably 2 μm or more and 15 μm or less.
Moreover, it is more preferable to disperse | distribute uniformly what mixed the said composition by disperse | distributing a roll mill, a bead mill, a sand mill etc.

Example 1
(1) In a flask equipped with a thermometer, a stirrer, a dropping funnel, and a reflux condenser, 400 g of cresol novolak resin (YDCN-704 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., epoxy equivalent = 208 g / eq) and propylene glycol monomethyl as a solvent 232 g of acetate was added and dissolved by heating. Subsequently, 0.3 g of hydroquinone as a polymerization inhibitor and 13 g of triphenylphosphine as a reaction catalyst were added thereto. This mixture was heated to 60 to 100 ° C., 140 g of acrylic acid was gradually added dropwise, and the mixture was reacted for about 10 hours until the acid value became 5 mgKOH / g or less. After cooling this reaction product to 60-90 ° C., 145 g of tetrahydrophthalic anhydride and 235 g of propylene glycol monomethyl acetate were added, and absorption peaks (1770 and 1850 cm ⁻¹ ) of acid anhydrides were determined by infrared absorption analysis. The reaction was allowed to proceed for about 4 hours until there was no photon, and a photocurable resin comprising a propylene glycol monomethyl acetate solution was obtained. The resulting propylene glycol monomethyl acetate solution had a nonvolatile content of 60% by weight and a solid acid value of 70 mgKOH / g.

(2) In a flask equipped with a reflux condenser, benzyl methacrylate / methacrylic acid having a monomer component and a weight ratio of 0.80 / 0.20, diethylene glycol monobutyl ether as a solvent, azobis as a polymerization initiator The thermosetting resin which consists of the acrylic copolymer of this synthesis example was obtained by making isobutyronitrile react at 70-120 degreeC for 10 hours by nitrogen atmosphere. The polymer solution thus obtained had a nonvolatile content of 40% by weight, a solid acid value of 132 mgKOH / g, and a weight average molecular weight of 19000.

(3) Using 50 parts by weight of dipentaerythritol hexaacrylate as a photosensitive monomer and 9 parts by weight of finely pulverized melamine (manufactured by Nissan Chemical Industries, Ltd.) as a thermosetting catalyst, the photocurability obtained in (1) above. 160 parts by weight of the resin and 60 parts by weight of the thermosetting resin obtained in (2), 3 parts by weight of BASF Irgacure 819 and 3 parts by weight of Irgacure TPO as a polymerization initiator, and aromatic hydrocarbon as a diluent Hydrous magnesium silicate particles having 144 parts by weight of titanium oxide particles (CR-50 manufactured by Ishihara Sangyo Co., Ltd.) having an average primary particle diameter of 0.25 μm coated with 40 parts by weight of C10 and aluminum oxide, and having an average primary particle diameter of 5 μm ( An alkali-soluble resist ink composition of Example 1 was obtained by blending 10.7 parts by weight of LMS-200 manufactured by Fuji Titanium Industry Co., Ltd. It was.

Example 2
By blending the same amount (parts by weight) of the same components as in Example 1 except that 10.7 parts by weight of hydrous magnesium silicate particles (LMP-100 manufactured by Fuji Titanium Industry Co., Ltd.) having an average primary particle size of 11 μm were blended. The alkali-soluble resist ink composition of Example 2 was obtained.

Example 3
Except for blending 40 parts by weight of the photocurable resin obtained in (1) above and 240 parts by weight of the thermosetting resin obtained in (2), the same components as in Example 1 (parts by weight) ) To obtain an alkali-soluble resist ink composition of Example 4.

Example 4
By blending the same components (in parts by weight) as in Example 1 except that 9 parts by weight of melamine cyanurate (MC-6000 manufactured by Nissan Chemical Industries, Ltd.) was used as the thermosetting catalyst, An alkali-soluble resist ink composition was obtained.

Comparative Example 1
Example 1 except that 50 parts by weight of tris- (2-acryloxylethyl) isocyanurate was used as the photosensitive monomer, and titanium oxide particles coated with aluminum oxide and hydrous magnesium silicate particles were not blended. The alkali-soluble resist ink composition of Comparative Example 1 was obtained by blending the same components in the same amount (parts by weight).

Comparative Example 2
By blending only the same amount (parts by weight) of the same components as in Example 1 except that only 200 parts by weight of the photocurable resin obtained in (1) above was blended as the resin component, the alkali of Comparative Example 2 was allowed. A melt resist ink composition was obtained.

Comparative Example 3
A comparative example is obtained by blending 160 parts by weight of titanium oxide particles coated with aluminum oxide and blending the same amount (parts by weight) of the same components as in Example 1 except that no hydrous magnesium silicate particles are blended. 3 alkali-soluble resist ink composition was obtained.

Comparative Example 4
The same components as in Example 1 except that 160 parts by weight of titanium oxide particles (R-650 manufactured by Sakai Chemical Industry Co., Ltd.) coated with silicon oxide and aluminum oxide were blended, and no hydrous magnesium silicate particles were blended. By blending the same amount (parts by weight), an alkali-soluble resist ink composition of Comparative Example 4 was obtained.

Comparative Example 5
Same as Example 1 except that 160 parts by weight of titanium oxide particles (CR-57 manufactured by Ishihara Sangyo Co., Ltd.) coated with silicon oxide, aluminum oxide and zirconium oxide were blended, and no hydrous magnesium silicate particles were blended. The alkali-soluble resist ink composition of Comparative Example 5 was obtained by blending the same amounts (parts by weight) of the components.

Comparative Example 6
The same as Example 1 except that no photosensitive monomer was used, and only 425 parts by weight of the thermosetting resin obtained in (2) above was added as a resin component, and no photopolymerization initiator was added. The alkali-soluble resist ink composition of Comparative Example 6 was obtained by blending the same amounts (parts by weight) of the components.

Comparative Example 7
The same components as in Example 1 (parts by weight) except that the thermosetting catalyst and the thermosetting catalyst were not used and only 242 parts by weight of the photocurable resin obtained in (1) above was blended as the resin component. ) To obtain an alkali-soluble resist ink composition of Comparative Example 7.

  Under the following conditions, test pieces on which resist films were developed by developing the alkali-soluble resist ink compositions of Examples 1 to 4 and Comparative Examples 1 to 7 were prepared.

Test piece preparation conditions Material: Copper + glass epoxy, glass epoxy (ELC-4970, manufactured by Sumitomo Bakelite)
2. 2. Pretreatment: After polishing the material with # 1000 abrasive, acid treatment with 10% hydrochloric acid, washing with water and air drying. Painting method: screen printing (100 mesh polyester material)
4). Hold time: 5 minutes Pre-drying: 80 ° C. × 30 minutes 6. Exposure: 600 mJ / cm ² (exposure machine, ECS-4011GX manufactured by Angraphic Co., Ltd., lamp: metal hydrolamp M64-L41 160 W / cm)
7). Hold time 5 minutes 8. Development: Wash with water for 90 seconds under the condition of water pressure of 0.25 MPa · s using 1% sodium carbonate with a liquid temperature of 30 ° C. 9. Firing 150 ° C. × 60 minutes 10. Others (1) For the resist ink composition of Comparative Example 6, a test piece was prepared after pre-drying 80 ° C. × 30 minutes after the above conditions 1, 2, 3, 4 and baking 150 ° C. × 60 minutes.
(2) About the resist ink composition of the comparative example 7, the test piece was produced in baking 150 degreeC x 60 minutes after said conditions 1, 2, 3, 45, and 6.

  The test pieces of Examples 1 to 4 and Comparative Examples 1 to 7 on which the resist film was formed were evaluated by the following test methods. The results are shown in Table 2.

Using a Mylar film created by the tackiness polyester material, after cooling to room temperature after precure was exposed to light paste was confirmed whether there is no abnormality.
○: When the film is peeled off from the coating film, there is no abnormality such as adhesion feeling. Δ: When the film is peeled off from the coating film, there is a slight adhesion feeling but there is no abnormality such as peeling off of the coating film. When the film is peeled off, there is a sticky feeling and there is peeling of the paint film

In developing property line and space (L / S) 200 / 200,190 / 190,180 / 180,170 / 170,160 / 160,150 / 150,140 / 140,130 / 130,120 / 120,110 / 110 , 100/100, 90/90, 80/80, 70/70, 60/60, 50/50, 40/40, 30/30, and 20/20 μm mylar film with a silver salt shielded from light Before the exposure, the film was pasted and exposed on the coating film to perform each step, and the measurement was carried out using a laser microscope (VK-9700, manufactured by Keyence Corporation) for evaluation.
○: L / S 100/100 μm or less could be developed Δ: L / S 100/100 to 150/150 μm could be developed ×: L / S 150/150 to 200/200 μm could be developed

Using a sensitivity step tablet (STOUFFER type), the exposure was performed on the coating film before exposure, and each step was performed, and the numerical value up to the developed place was read and evaluated.

According to JIS-K5400 8.5.2, a cross cut was made in a grid pattern, and then the state of peeling after peeling with a cellophane adhesive tape (specified in JISZ1522) was visually confirmed. The results were evaluated as follows.
○: No change was observed in all of the 100 crosscut portions. Δ: Peeling occurred in 1 to 10 places out of 100 crosscut portions. X: 11 to 11 out of 100 crosscut portions. Peeling occurred at 100 locations

Hardness According to JIS-K5400 8.4.2, the hardness until the coating film was broken with pencil hardness was visually confirmed.

The cut surface was cut with a cutting machine with the cut film surface facing up, and the cut surface was visually checked for peeling after taping with a cellophane adhesive tape (as defined in JIS-Z1522). The results were evaluated as follows.
○: No peeling of the coating film is seen Δ: The peeling of the coating film is seen in either the material glass epoxy + copper or glass epoxy ×: The peeling is seen in both materials

The test piece was immersed in an acid-resistant 10% sulfuric acid aqueous solution for 30 minutes and then evaluated.
○: No abnormality was observed in the coating film △: Some abnormality was observed in the coating film ×: Peeling of the coating film was observed

Evaluation was performed after the test piece was immersed in alkali-resistant 10% sodium hydroxide for 30 minutes.
○: No abnormality was observed in the coating film △: Some abnormality was observed in the coating film ×: Peeling of the coating film was observed

A test piece was prepared on a substrate (upicel manufactured by Ube Eximo Corporation) laminated in the order of bending-resistant copper 35 μm + polyimide film 25 μm + aluminum 300 μm, and φ2 mm, 90 ° bending applied according to JIS-K5600 5.1. The film was checked visually for abnormalities such as cracks.
○: No abnormality is observed in the coating film △: There is an abnormality such as a crack, but there is no peeling of the coating film ×: There is peeling of the coating film

The solder-resistant test piece was acid-treated with 10% hydrochloric acid, washed and dried, and immersed in a water-soluble preflux (Taface F2 manufactured by Shikoku Kasei Co., Ltd., liquid temperature 40 ° C.) for 60 seconds. What was washed with water and dried was immersed in a solder bath (solder coat H63A-B20, liquid temperature 260 ° C.) for 30 seconds, and it was visually confirmed that there was no abnormality in the coating film.
○: No abnormality was observed in the coating film △: Some abnormality was observed in the coating film ×: Peeling of the coating film was observed

After treatment with a gold- resistant plating electroless nickel plating bath, the treatment was carried out in an electroless gold plating bath, and it was visually confirmed whether there was any abnormality in the coating film.
○: No abnormality was observed in the coating film △: Some abnormality was observed in the coating film ×: Peeling of the coating film was observed

PCT resistant
It was allowed to stand in saturated steam at 121 ° C. for 9 hours, and it was visually confirmed whether there was any abnormality in the coating film.
○: No abnormality was observed in the coating film △: Some abnormality was observed in the coating film ×: Peeling of the coating film was observed

An insulating comb-type electrode test piece (L / S = 100/100 μm = copper / glass epoxy) was prepared using the above-mentioned test piece preparation conditions, and a voltage of 24V DC in a constant temperature and humidity device at 60 ° C. and 90% humidity. Was applied and allowed to stand for 1000 hours, and then the insulation resistance value was measured and evaluated.
○: Ion migration was not observed when the insulation resistance value was 10 ¹⁰ or more.
Δ: Insulation resistance value 10 ¹⁰ or more but some ion migration was observed ×: Ion migration was observed with insulation resistance value 10 ¹⁰ or less

A reflectance color difference meter (CM-3600d, manufactured by Konica Minolta Co., Ltd.) was used to measure a reflectance of 450 to 700 nm, and an average value was measured.

A test piece was placed in a hot air drying furnace having a heat resistance of 125 ° C. and heated for 1000 hours, and then the adhesion and reflectance were evaluated and confirmed.

The emissivity was measured and confirmed with an emissivity radiometer (D & S AERD manufactured by Kyoto Electronics Industry Co., Ltd.).

  From Tables 1 and 2, the resist film obtained from the alkali-soluble resist ink composition of Examples 1 to 4 containing a photocurable resin and a thermosetting resin is a photocurable resin or a thermosetting resin. Compared to the resist film obtained from the alkali-soluble resist ink composition of Comparative Examples 2, 6, and 7 containing only one of them, excellent cutting properties, bending resistance, solder resistance, gold plating resistance, It was found to exhibit PCT resistance, insulation, heat resistance, reflectance and emissivity.

  Further, from Examples 1 to 4, in order to obtain a resist film having excellent cutting properties, bending resistance, solder resistance, gold plating resistance, PCT resistance, insulation, heat resistance, reflectance and emissivity, It has been found that it is effective that the thermosetting resin is contained in an amount of 35 to 600 parts by weight with respect to 100 parts by weight of the photocurable resin.

  From Tables 1 and 2, the resist films obtained from the alkali-soluble resist ink compositions of Examples 1 to 4 containing titanium oxide particles coated with aluminum oxide and hydrous magnesium silicate particles were coated with aluminum oxide. Compared to the resist film obtained from the alkali-soluble resist ink composition of Comparative Example 1 that does not contain the formed titanium oxide particles and hydrous magnesium silicate particles, the reflectance (heat resistance) of the test piece after heating, heating It was found that both the reflectance and the radiation rate of the previous solid test piece showed high values of radiation rate, light reflectance and excellent heat resistance of 80% or more.

  In addition, in order to obtain a resist film having higher emissivity, light reflectance and excellent heat resistance than in Examples 1 to 4, titanium oxide particles having an average primary particle diameter of 0.20 μm or more and 0.30 μm or less. However, it was found that it was effective when contained in an amount of 50 to 70 parts by weight with respect to 100 parts by weight of the total of the photocurable resin and the thermosetting resin.

  The resist film obtained from the alkali-soluble resist ink composition of Comparative Examples 3 to 5 which contains titanium oxide particles coated with aluminum oxide but does not contain hydrous magnesium silicate particles contains titanium oxide particles and Since the emissivity, light reflectance, and heat resistance were particularly poor compared to the resist films obtained from the alkali-soluble resist ink compositions of Examples 1 to 4 containing any of the hydrous magnesium silicate particles, it was excellent. In order to obtain characteristics such as emissivity, light reflectance, and heat resistance, it has been found that the combination of titanium oxide particles coated with aluminum oxide and hydrous magnesium silicate particles (talc) is important.

  In addition, in order to obtain a resist film having a high value of emissivity, light reflectance and excellent heat resistance from Examples 1 to 4, hydrous magnesium silicate particles having an average primary particle diameter of 2 μm to 15 μm are oxidized. It has been found that it is effective to contain 5 to 10 parts by weight with respect to 100 parts by weight of titanium oxide particles coated with aluminum.

Claims (7)

Light obtained by reacting a reaction product of an unsaturated carboxylic acid with one or more compounds selected from a novolac type epoxy resin, a heterocyclic epoxy resin and a bisphenol A type epoxy resin with an organic polybasic acid anhydride A curable resin;
A photopolymerization initiator;
A diluent,
A thermosetting resin made of an acrylic copolymer;
Titanium oxide particles coated with aluminum oxide, hydrous magnesium silicate particles (talc),
An alkaline solution-soluble resist ink composition comprising:   The alkali solution-soluble resist ink composition according to claim 1, wherein the thermosetting resin is contained in an amount of 35 to 600 parts by weight with respect to 100 parts by weight of the photocurable resin.   3. The alkali solution-soluble composition according to claim 1, wherein the titanium oxide particles are contained in an amount of 50 to 70 parts by weight with respect to 100 parts by weight of the total of the photocurable resin and the thermosetting resin. Type resist ink composition.   The alkali solution-soluble resist ink composition according to claim 1, wherein the titanium oxide particles have an average primary particle size of 0.20 μm or more and 0.30 μm or less.   The alkali solution-soluble resist ink composition according to claim 1, wherein the titanium oxide particles are of a rutile type.   6. The alkaline solution-soluble resist ink composition according to claim 1, wherein the hydrous magnesium silicate particles are contained in an amount of 5 to 10 parts by weight with respect to 100 parts by weight of the titanium oxide particles. object.   The alkali solution-soluble resist ink composition according to any one of claims 1 to 6, wherein the hydrous magnesium silicate particles have an average primary particle size of 2 µm or more and 15 µm or less.