TWI620019B - Alkali developing type thermosetting resin composition, printed wiring board - Google Patents

Abstract

The present invention provides an alkali-developable thermosetting resin composition and printed wiring board capable of forming a patterned layer by development even when highly filled with an inorganic filler. Furthermore, an object of the present invention is to provide an alkali-developable thermosetting resin composition and a printed wiring board that can form a pattern layer having excellent cold-heat cycle characteristics.

An alkali-developable thermosetting resin composition characterized by containing an alkali-developable resin, a heat-reactive compound, an inorganic filler, and a photo-alkali generator, and the alkali-developable alkali is developed by selective light irradiation The addition reaction of the resin with the aforementioned heat-reactive compound can form a negative pattern by alkali development.

Description

Alkali developing type thermosetting resin composition, printed wiring board

The present invention relates to an alkali-developable thermosetting resin composition and a printed wiring board.

In recent years, as materials for solder resists for printed wiring boards or flexible printed wiring boards, due to environmental concerns, alkali-developing photocurable resin compositions using an alkaline aqueous solution as a developing solution have become mainstream. As such an alkali-developable photocurable resin composition, as shown in Patent Documents 1 and 2, a modified resin containing epoxy acrylate derived from epoxy resin modification is generally used (hereinafter, it is also abbreviated as Resin composition of epoxy acrylate).

As a method of forming a solder resist using such a photo-curable resin composition, a photo-curable resin composition is applied and dried on a substrate to form a resin layer, and the resin layer is irradiated with light in a pattern Afterwards, it is developed with an alkaline developer to form a designated pattern.

In addition, printed wiring boards or flexible printed wiring boards are used by being mounted on various devices. Therefore, it is required to be resistant to rapid changes in the environment such as temperature. Therefore, the solder resist is also required to have a high temperature Resistance to temperature change, but when the difference between the linear expansion coefficient (CTE) of the thermosetting resin and the substrate or copper, underfill and other substrate forming materials is large, it may be included in the TCT (thermal cycle test). The problem of cracks.

Regarding this, in recent years, it has been widely carried out to combine CTE of thermosetting resin with CTE of peripheral member materials. For example, in general, by highly filling an inorganic filler with a thermosetting resin, the CTE is reduced to suppress curing shrinkage.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Unexamined Patent Publication No. 61-243869 (applicable patent scope)

[Patent Document 2] Japanese Patent Laid-Open No. 3-250012 (Patent Application Range)

However, when the thermosetting resin composition is highly filled with an inorganic filler, it prevents light from penetrating to the deep part. At this time, there is a problem that resolution is not obtained and it is difficult to form a pattern layer.

Therefore, an object of the present invention is to provide an alkali-developable thermosetting resin composition and a printed wiring board that can form a pattern layer by development even if highly filled with an inorganic filler. Further, the object of the present invention is to provide an alkali-developing type thermal hardening capable of forming a pattern layer with excellent cold-heat cycle characteristics Resin composition, printed wiring board.

The inventors of the present invention have worked hard to solve the above-mentioned problems and found that the above-mentioned problems can be solved by adopting the following configuration, and the present invention has been completed.

That is, the alkali-developable thermosetting resin composition of the present invention is characterized by containing an alkali-developable resin, a heat-reactive compound, an inorganic filler, and a photobase generator, and by selective light irradiation The alkali-developable resin and the heat-reactive compound undergo an addition reaction to form a negative pattern by alkali development.

In the alkali-developable thermosetting resin composition of the present invention, the average particle diameter of the inorganic filler is preferably 1 μm or less.

In addition, in the alkali-developable thermosetting resin composition of the present invention, the refractive index difference between the inorganic filler and the resin is preferably 0.3 or less.

Furthermore, in the alkali-developable thermosetting resin composition of the present invention, the refractive index of the inorganic filler is preferably 1.45 or more and 1.65 or less.

In addition, the alkali-developable thermosetting resin composition of the present invention preferably generates a peak of heat generation in DSC measurement by light irradiation; or, the alkali-developing thermosetting resin composition after light irradiation in DSC The heating start temperature during the measurement is lower than the heating start temperature of the non-irradiated alkali-developing thermosetting resin composition in DSC measurement; or, the alkali-developing thermosetting resin composition after light irradiation is in DSC Determination The peak heat generation temperature in the range is lower than the peak heat generation temperature in the DSC measurement of the non-irradiated alkali-developing thermosetting resin composition.

According to the present invention, it is possible to provide an alkali-developable thermosetting resin composition capable of forming a pattern layer by development, and a printed wiring board. Further, according to the present invention, it is possible to provide an alkali-developable thermosetting resin composition and a printed wiring board capable of forming a pattern layer having excellent curability and cold-heat cycle characteristics.

[Fig. 1] Fig. 1 is a schematic diagram showing an example of a pattern forming method using the alkali-developing thermosetting resin composition of the present invention.

[FIG. 2] FIG. 2 is a DSC diagram of a resin layer composed of the alkali-developable thermosetting resin composition of Example 1 of the present invention.

[FIG. 3] FIG. 3 is a cross-sectional view of a double-sided printed wiring substrate for explaining the evaluation of depressions on a through hole.

The alkali-developable thermosetting resin composition of the present invention (hereinafter sometimes also referred to as "thermosetting resin composition") is characterized by containing an alkali-developable resin, a heat-reactive compound, an inorganic filler, And photo-alkali generator, and alkali-developable resin by selective light irradiation Addition reaction with heat-reactive compounds can develop negative patterns with alkali development. Here, pattern formation means forming a pattern-shaped hardened object, that is, a pattern layer.

In a resin layer composed of a thermosetting resin composition, alkali is generated on the surface by light irradiation. Furthermore, with the generated base, the photobase generator will become unstable, and it may be considered that the base will further chemically proliferate to the deep part. Here, the alkali system acts as a catalyst in the addition reaction between the alkali-developable resin and the heat-reactive compound, and at the same time, the addition reaction proceeds to the deep part. Therefore, in the light irradiation part, the resin layer is hardened to the deep part.

Therefore, even when the inorganic filler is highly filled, the pattern layer can be easily formed after the thermosetting resin composition is irradiated with light in a pattern shape and the non-irradiated portion is removed by alkali development.

In addition, the thermosetting resin composition of the present invention is cured by the addition reaction of the alkali-developable resin and the thermoreactive compound. Therefore, compared with the photocurable resin composition, less deformation or curing shrinkage can be obtained. Graphic layer.

The thermosetting resin composition may not be cured even if heated in an unirradiated state, and becomes a composition that can be cured by heat only after light irradiation.

The thermosetting resin composition of the present invention preferably generates a heating peak in the DSC measurement by light irradiation; or, the heating start temperature of the thermosetting resin composition after the light irradiation in the DSC measurement is better than The irradiated thermosetting resin composition has a lower heating start temperature in the DSC measurement; or, the peak heat generation temperature in the DSC measurement of the irradiated thermosetting resin composition is lower than that of the unirradiated thermosetting resin composition The peak heat generation temperature in the DSC measurement is lower.

In addition, the thermosetting resin composition of the present invention has a temperature difference between the thermosetting resin composition after light irradiation and the unirradiated thermosetting resin composition in the DSC measurement (also referred to as △ T start) )) Or the temperature difference (also referred to as ΔT peak) of the peak heat generation temperature, preferably 10 ° C or higher, more preferably 20 ° C or higher, and still more preferably 30 ° C or higher.

Here, △ T start means that a thermosetting resin composition of the same composition is prepared. After one is irradiated with light and the other is not irradiated with light, the DSC (differential scanning calorimetry) measurement is performed separately. After that, the resin composition after light irradiation showed a temperature difference between the heat generation start temperature at which the curing reaction started and the heat generation start temperature of the unirradiated resin composition. ΔT peak refers to the temperature difference between the peak temperature of the resin composition after light irradiation and the non-irradiation after the DSC measurement is performed in the same manner.

In addition, the light irradiation amount of the thermosetting resin composition after light irradiation in the DSC measurement is to increase the irradiation amount without causing a shift in the heating peak temperature of the thermosetting resin composition due to light irradiation ( Saturation) light exposure.

When ΔT start or ΔT peak is 10 ° C. or higher, the occurrence of so-called blur remaining in the non-irradiated portion due to alkali development or the so-called erosion where the light-irradiated portion is removed due to alkali development can be suppressed. In addition, by setting ΔT start or ΔT peak to 10 ° C. or higher, the heating temperature range that can be taken in the heating step (B1) described later can be widened.

Hereinafter, each component of the thermosetting resin composition will be described in detail.

[Alkali developing resin]

The alkali-developable resin is a resin containing one or more functional groups among a phenolic hydroxyl group, a thiol group, and a carboxyl group, and can be developed with an alkaline solution, preferably a compound having two or more phenolic hydroxyl groups, a carboxyl group-containing compound Resins, compounds with phenolic hydroxyl and carboxyl groups, compounds with more than two thiol groups.

Compounds having two or more phenolic hydroxyl groups include phenol novolak resins, alkylphenol novolak resins, bisphenol A novolak resins, dicyclopentadiene type phenol resins, Xylok type phenol resins, terpene modification Phenol resins, polyvinyl phenols, bisphenol F, bisphenol S type phenol resins, poly-P-hydroxystyrene, condensates of naphthol and aldehydes, condensates of dihydroxynaphthalene and aldehydes, etc. Resin.

In addition, as the phenol resin, compounds having a biphenyl skeleton, a phenylene skeleton, or both skeletons; and phenol, o-cresol, p-cresol, m-cresol, which are phenolic hydroxyl-containing compounds, can be used. 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, catechin Phenol, resorcinol, hydroquinone, methylhydroquinone, 2,6-dimethylhydroquinone, trimethylhydroquinone, gallophenol, resorcinol, etc. are synthesized with various skeleton phenol resins.

These can be used alone or in combination of two or more.

The carboxyl group-containing resin can be a known carboxyl group-containing resin. The presence of the carboxyl group makes the resin composition alkali developable. Furthermore, in addition to the carboxyl group, a compound having an ethylenic unsaturated bond in the molecule can also be used. In the present invention, as the carboxyl group-containing resin, it is preferred to use only For example, the following carboxyl group-containing resin having no ethylenically unsaturated double bond (1) is used.

Specific examples of the carboxyl group-containing resin usable in the present invention include the compounds listed below (both oligomers and polymers).

(1) Unsaturated carboxylic acid such as (meth) acrylic acid, containing carboxyl group by copolymerization with unsaturated group-containing compounds such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, isobutylene, etc. Of resin. Furthermore, lower alkyl means an alkyl group having 1 to 5 carbon atoms.

(2) Diisocyanate such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, and carboxyl containing dimethylolpropionic acid, dimethylolbutanoic acid Alcohol compounds and polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, polyolefin-based polyols, acrylic-based polyols, bisphenol A-based alkylene oxide adduct diol, having phenolic hydroxyl groups Carbamate resins containing carboxyl groups obtained by addition polymerization of glycol compounds such as alcoholic hydroxyl compounds.

(3) Diisocyanate compounds such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, and polycarbonate-based polyol, polyether-based polyol, polyester-based polyol, Aminomethyl obtained by the addition polymerization of diol compounds such as polyolefin polyols, acrylic polyols, bisphenol A alkylene oxide adduct diols, compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups An urethane resin containing a terminal carboxyl group formed by reacting the end of the ester resin with an acid anhydride.

(4) Diisocyanate, with bisphenol A epoxy resin, hydrogenation Bifunctional epoxy resin of bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin, etc. (methyl ) Carboxyl group-containing urethane resin obtained by the addition polymerization reaction of acrylic acid ester or its partial anhydride modified product, carboxyl group-containing diol compound and diol compound.

(5) In the resin synthesis of (2) or (4) above, a compound having one hydroxyl group and one or more (meth) acryloyl groups in the molecule such as hydroxyalkyl (meth) acrylate is added, and the terminal ( Group) Carbamate resin containing carboxyl group which is acrylamide.

(6) In the synthesis of the resin of (2) or (4) above, the mole reaction product such as isophorone diisocyanate and pentaerythritol triacrylate has one isocyanate group and one or more (methyl) groups in the molecule Acrylic compound, and terminal (meth) acrylic compound containing carboxyl group carbamate resin.

(7) Reaction of unsaturated monocarboxylic acid such as (meth) acrylic acid with the above-mentioned multifunctional (solid) epoxy resin, and addition of phthalic anhydride and tetrahydrophthalic acid to the hydroxyl group present in the side chain Carboxylic acid-containing resins of dibasic acid anhydrides such as dicarboxylic anhydride and hexahydrophthalic anhydride.

(8) The saturated monocarboxylic acid is reacted with the polyfunctional (solid) epoxy resin as described above, and phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic acid are added to the hydroxyl group present in the side chain. A carboxyl group-containing resin of binary acid anhydride such as formic anhydride.

(9) Reacting (meth) acrylic acid with a multifunctional epoxy resin that epoxidizes the hydroxy group of a bifunctional (solid) epoxy resin with epichlorohydrin, in The resulting hydroxyl group is added to the resin containing carboxyl group with a dibasic acid anhydride.

(10) A carboxyl group-containing polyester resin in which a dicarboxylic acid is reacted with a polyfunctional oxetane resin as described later to add a dibasic acid anhydride to the generated first-stage hydroxyl group.

(11) A reaction product obtained by reacting a polybasic acid anhydride and a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide and propylene oxide to obtain a carboxyl group-containing resin.

(12) The reaction product obtained by reacting a saturated monocarboxylic acid and a compound having a plurality of phenolic hydroxyl groups in one molecule with alkylene oxide such as ethylene oxide and propylene oxide is reacted. A resin containing carboxyl group obtained by the reaction of acid anhydride.

(13) The reaction product obtained by reacting a monocarboxylic acid containing an unsaturated group and a compound having a plurality of phenolic hydroxyl groups in one molecule with alkylene oxide such as ethylene oxide and propylene oxide, and the resulting reaction A carboxyl group-containing resin obtained by reacting the product with a polybasic acid anhydride.

(14) The reaction product obtained by reacting a saturated monocarboxylic acid with a compound having a plurality of phenolic hydroxyl groups in one molecule and a cyclic carbonate compound such as ethyl carbonate and propyl carbonate is obtained. A carboxyl group-containing resin obtained by reacting the reaction product with a polybasic acid anhydride.

(15) A reaction product obtained by reacting a polybasic acid anhydride with a compound having a plurality of phenolic hydroxyl groups in one molecule and a cyclic carbonate compound such as ethyl carbonate and propyl carbonate, etc., containing a carboxyl group Of resin.

(16) Use monocarboxylic acids containing unsaturated groups and compounds with a plurality of phenolic hydroxyl groups in one molecule and ethyl carbonate, propyl carbonate, etc. The reaction product obtained by the reaction of the cyclic carbonate compound reacts, and the resulting reaction product reacts with a polybasic acid anhydride to obtain a carboxyl group-containing resin.

(17) A compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule of p-hydroxyphenylethanol and the like and a saturated monocarboxylic acid is reacted with an epoxy compound having a plurality of epoxy groups in one molecule , And then react with polyanhydrides such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid and the like to the alcoholic hydroxyl group of the resulting reaction product to obtain a carboxyl group-containing resin .

(18) A compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule of p-hydroxyphenylethanol and the like is reacted with an epoxy compound having a plurality of epoxy groups in one molecule, and then Malay An acid anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid and other polyanhydrides react with the alcoholic hydroxyl group of the resulting reaction product to obtain a carboxyl group-containing resin.

(19) A compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule of p-hydroxyphenylethanol and the like, and an unsaturated group-containing monocarboxylic acid such as (meth) acrylic acid in one molecule An epoxy compound having a plurality of epoxy groups is reacted, and then the polyhydric anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic acid is reacted with the alcohol of the resulting reaction product Resin containing carboxyl groups from the reaction of reactive hydroxyl groups.

(20) Further, in the molecule of epoxypropyl (meth) acrylate, α-methylepoxypropyl (meth) acrylate, etc., it has one epoxy group and one or more (meth) propylene The carboxyl group-containing resin is obtained by adding the compound of the acetyl group to the resin as described in any one of (1) to (19) above.

The alkali-developable resin as described above is in the main chain. The side chain of the polymer has many carboxyl groups, hydroxyl groups, etc., so it can be developed with an alkaline aqueous solution.

In addition, the hydroxyl equivalent or carboxyl equivalent of the carboxyl group-containing resin is preferably 80 to 900 g / eq., And more preferably 100 to 700 g / eq. When the hydroxyl equivalent or carboxyl equivalent exceeds 900 g / eq., The adhesion of the pattern layer may not be obtained, or alkali development may be difficult. On the other hand, when the hydroxyl equivalent or carboxyl equivalent is less than 80g / eq., In order to dissolve the light irradiated portion by the developing solution, the line will be excessively thinned, and the light irradiated portion and the unirradiated The parts are dissolved and peeled off with the developer without distinction, and it is difficult to draw the resist pattern normally, so it is not good. In addition, when the carboxyl group equivalent or the phenol group equivalent is large, it is possible to develop even when the content of the alkali-developable resin is small, which is preferable.

In addition, although the weight average molecular weight of the alkali-developable resin used in the present invention varies with the resin skeleton, it is preferably in the range of 2,000 to 150,000, and more preferably in the range of 5,000 to 100,000. When the weight average molecular weight is less than 2,000, the non-adhesive performance may be poor, the moisture resistance of the resin layer after light irradiation may be poor, the film may be reduced during development, and the resolution may be poor. On the other hand, when the weight average molecular weight exceeds 150,000, the developability may be significantly deteriorated, and the storage stability may be poor.

In this specification, (meth) acrylate refers to the general term acrylate, methacrylate, and mixtures of these, and other similar expressions are also the same.

Examples of the compound having a thiol group include trimethylolpropane thiopropionate, pentaerythritol thiopropionate, and ethylene glycol disulfide Glycolate, 1,4-butanediol dithioglycolate, trimethylolpropane ginseng thioglycolate, pentaerythritol thioglycolate, bis (2-mercaptoethyl) ether, 1 , 4-butane dithiol, 1,3,5-trimercaptomethylbenzene, 1,3,5-trimercaptomethyl-2,4,6-trimethylbenzene, polymers containing terminal thiol groups Ether, polythioether containing terminal thiol group, thiol compound obtained by reaction of epoxy compound and hydrogen sulfide, thiol having terminal thiol group obtained by reaction of polythiol compound and epoxy compound Compounds etc.

The alkali-developable resin is preferably a resin containing a carboxyl group or a compound having a phenolic hydroxyl group. In addition, the alkali-developable resin is preferably a non-photosensitive one that does not have a photocurable structure, such as epoxy acrylate. Since such a non-photosensitive alkali-developable resin does not have an ester bond derived from epoxy acrylate, it has high resistance to the scum removal liquid. Therefore, it is possible to form a pattern layer having excellent hardening characteristics. In addition, since it does not have a photo-curable structure, curing shrinkage can be suppressed.

When the alkali-developable resin is a resin containing a carboxyl group, it can be developed with a weakly alkaline aqueous solution compared to the case of a phenolic resin. Examples of the weakly alkaline aqueous solution are those in which sodium carbonate is dissolved. By developing with a weak alkaline aqueous solution, it is possible to suppress development of the light-irradiated portion. In addition, the light irradiation time in step (B) or the heating time in step (B1) can be shortened.

[Thermally reactive compound]

The heat-reactive compound is a resin having a functional group capable of undergoing a hardening reaction by heat. Examples include epoxy resins and polyfunctional oxetane compounds.

The above-mentioned epoxy resin is a resin having an epoxy group, and any known ones can be used. Examples include bifunctional epoxy resins having two epoxy groups in the molecule, and multifunctional epoxy resins having many epoxy groups in the molecule. Furthermore, it may be a hydrogenated bifunctional epoxy compound.

Multifunctional epoxy compounds include bisphenol A epoxy resin, brominated epoxy resin, novolac epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, epoxypropyl group Amine type epoxy resin, hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bixylenol type or biphenol type epoxy resin or a mixture of these, Bisphenol S type epoxy resin, bisphenol A novolac type epoxy resin, tetraphenol ethane type epoxy resin, heterocyclic epoxy resin, diglycidyl phthalate resin, tetracyclic Oxypropyl xylenyl ethane resin, epoxy resin containing naphthyl group, epoxy resin having dicyclopentadiene skeleton, epoxy methacrylate copolymer epoxy resin, cyclohexyl maleic amide Copolymerized epoxy resin of imine and glycidyl methacrylate, CTBN modified epoxy resin, etc.

Other liquid bifunctional epoxy resins include vinylcyclohexene diepoxide, (3 ', 4'-epoxycyclohexylmethyl) -3,4-epoxycyclohexane carboxyl Alicyclic epoxy resins such as acid esters, (3 ', 4'-epoxy-6'-methylcyclohexylmethyl) -3,4-epoxy-6-methylcyclohexane carboxylate Resin. Epoxy resins containing naphthalene groups are preferred because they can inhibit the thermal expansion of the cured product.

The above epoxy resins may be used alone or in combination of two or more.

The above polyfunctional oxetane compounds, except bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetan Alkylmethoxy) methyl] ether, 1,4-bis [(3-methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl 3-oxetanylmethoxy) methyl] benzene, acrylic acid (3-methyl-3-oxetanyl) methyl ester, acrylic acid (3-ethyl-3-oxetanyl Butyl) methyl ester, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate or the In addition to polyfunctional oxetanes such as oligomers or copolymers, etc., oxetane alcohol and novolak resin, poly (p-hydroxystyrene), carudo type (cardo type) Bisphenols, calixarenes, resorcinol calixresornes (calixresorcinarenes), or ethers of hydroxyl-containing resins such as silsesquioxane, etc. Other examples include copolymers of unsaturated monomers having an oxetane ring and alkyl (meth) acrylates.

Here, when the heat-reactive compound has a benzene skeleton, heat resistance is improved, which is preferable. In addition, when the thermosetting resin composition contains a white pigment, the heat-reactive compound is preferably an alicyclic skeleton. With this, the photoreactivity can be improved.

As the blending amount of the heat-reactive compound, the equivalent ratio with the alkali-developable resin (heat-reactive group: alkali-developable group) is preferably 1: 0.1 to 1:10, more preferably 1: 0.2 to 1: 5. When it is within the range of the blending ratio, the development becomes good.

[Photobase generator]

Photobase generators are those in which the molecular structure changes by irradiation with ultraviolet light, visible light, or the like, or the molecules are cracked to generate one or more types of catalysts that can function as an addition reaction catalyst for the above heat-reactive compounds Of basic substances. Examples of the basic substance include secondary amines and tertiary amines.

Examples of the photobase generator include α-aminoacetophenone compounds, oxime ester compounds, or having an oxyimino group, N-methylated aromatic amine group, and N-acetylated aromatic amine group , Nitrobenzylcarbamate group, alkoxybenzylcarbamate group and other substituents, and other compounds.

The α-aminoacetophenone compound has a benzoin ether bond in the molecule. When exposed to light, it will cause cracking in the molecule and generate an alkaline substance (amine) with a hardening catalyst. As a specific example of the α-aminoacetophenone compound, (4-morpholinylbenzyl) -1-benzyl-1-dimethylaminopropane (Irgacure 369, trade name, manufactured by BASF JAPAN) can be used Or 4- (methylthiobenzyl) -1-methyl-1-morpholinylethane (Irgacure 907, trade name, manufactured by BASF JAPAN), 2- (dimethylamino) -2- Commercially available compounds such as [(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone (Irgacure 379, trade name, manufactured by BASF JAPAN) or Its solution.

The oxime ester compound can be used as long as it generates a basic substance by light irradiation. The oxime ester compound includes CGI-325 manufactured by BASF JAPAN, Irgacure OXE01, Irgacure OXE02, N-1919 manufactured by ADEKA, and NCI-831 as commercial products. In addition, a compound having two oxime ester groups in the molecule can also be suitably used. Specifically, an oxime ester compound having a carbazole structure represented by the following general formula can be cited.

(In the formula, X represents a hydrogen atom, an alkyl group having 1 to 17 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a phenyl group, and a phenyl group (the alkyl group having 1 to 17 carbon atoms and 1 to 8 carbon atoms) Alkoxy group, amine group, alkyl amine group or dialkyl amine group of C 1-8 alkyl group), naphthyl group (with alkyl group having 1 to 17 carbon atoms, carbon number 1 to 8 Alkoxy group, amine group, alkyl group with 1 to 8 carbon atoms or dialkylamine group), Y and Z represent hydrogen atom, alkyl group with 1 to 17 carbon atoms 1-8 alkoxy groups, halo groups, phenyl groups, phenyl groups (including C1-C17 alkyl groups, C1-C8 alkoxy groups, amine groups, C1-C8 alkyl groups Alkylamine group or dialkylamine group substituted), naphthyl group (C1-C17 alkyl group, C1-C8 alkoxy group, amine group, C1-C8 alkyl group Substituted by alkylamine or dialkylamine), anthracenyl, pyridyl, benzofuranyl, benzothienyl, Ar represents a bond, or alkylene, vinylidene, carbon number 1-10 Phenylene, biphenylene, pyridyl, naphthyl, thiophene, anthracenyl, thienyl, furanyl, 2,5-pyrrole-diyl, 4,4'-stilbene-bis Radical, 4,2'-styrene-diyl, n is an integer of 0 or 1).

In particular, in the aforementioned general formula, X and Y are preferably methyl or ethyl, Z is methyl or phenyl, n is 0, Ar is a bond, or phenylene, naphthyl, thiophene or Thienyl.

In addition, preferred carbazole oxime ester compounds can also be exemplified. The compound represented by the following general formula.

(In the formula, R ¹ represents an alkyl group having 1 to 4 carbon atoms, or a phenyl group which may be substituted with a nitro group, a halogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a group having 1 to 4 carbon atoms An alkyl group, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group which may be substituted with an alkyl group or alkoxy group having 1 to 4 carbon atoms. R ³ is an oxygen atom or a sulfur atom, which means C1-C20 alkyl substituted with phenyl, benzyl substituted with C1-C4 alkoxy. R ⁴ represents nitro or acyl represented by XC (= O)- .X represents an aryl group, a thienyl group, a morpholinyl group, a thiophenyl group which may be substituted with an alkyl group having 1 to 4 carbon atoms, or a structure represented by the following formula).

Others include Japanese Patent Application Publication No. 2004-359639, Japanese Patent Application Publication No. 2005-097141, Japanese Patent Application Publication No. 2005-220097, Japanese Patent Application Publication No. 2006-160634, Japanese Patent Application Publication No. 2008-094770, Japan Special Table No. 2008-509967, Japan Carbazole oxime ester compounds described in Japanese Patent Publication No. 2009-040762 and Japanese Patent Laid-Open No. 2011-80036.

Specific examples of the compound having an acyloxyimino group include O, O'-succinic acid acetophenone oxime, O, O'-succinic acid diphenone ketoxime, benzophenone oxime acrylate -Styrene copolymer, etc.

Specific examples of the compound having an N-formylated aromatic amine group and an N-formylated aromatic amine group include, for example, di-N- (p-formylamino) diphenylmethane, di -N (p-ethylamido) diphenylmethane, di-N- (p-benzylamide) diphenylmethane, 4-methylacetylamido stilbene, 4-ethylamido Stilbene, 2,4-Dimethylaminoaminodistyrene, 1-Methylaminoaminonaphthalene, 1-Ethylaminoaminonaphthalene, 1,5-Dimethylaminoaminonaphthalene, 1- Methylaminoanthracene, 1,4-dimethylacetoaminoanthracene, 1-ethenylaminoanthracene, 1,4-dimethylacetoaminoanthraquinone, 1,5-dimethylacetoamine Anthraquinone, 3,3'-dimethyl-4,4'-dimethylaminoaminobiphenyl, 4,4'-dimethylaminoaminobenzophenone, etc.

Specific examples of the compound having a nitrobenzylcarbamate group and an alkoxybenzylcarbamate group include, for example, bis {{(2-nitrobenzyl) oxy} carbonyl} di Aminodiphenylmethane, 2,4-bis {{(2-nitrobenzyl) oxy} stilbene, bis {{(2-nitrobenzyloxy) carbonyl} hexane-1,6 -Diamine, m-xylidine {{(2-nitro-4-chlorobenzyl) oxy} amide amide, etc.

The photobase generator is preferably an oxime ester compound or an α-aminoacetophenone compound. The α-aminoacetophenone compound is particularly preferably one having 2 or more nitrogen atoms.

As other light base generators, WPBG-018 (trade name: 9-anthrylmethyl N, N'-diethylcarbamate), WPBG-027 (trade name: (E) -1- [3- (2-hydroxyphenyl) -2-propenoyl] piperidine), WPBG-082 (trade name: guanidinium2- (3-benzoylphenyl) propionate), WPBG-140 (trade name: 1- (anthraquinon-2-yl) ethyl imidazolecarboxylate), etc.

Also, Japanese Patent Laid-Open No. 11-71450, International Publication No. 2002/051905, International Publication No. 2008/072651, Japanese Patent Laid-Open No. 2003-20339, Japanese Patent Laid-Open No. 2003-212856, Japanese Patent Laid-Open 2003 -344992, JP 2007-86763, JP 2007-231235, JP 2008-3581, JP 2008-3582, JP 2009-280785, JP JP 2009-080452, JP 2010-95686, JP 2010-126662, JP 2010-185010, JP 2010-185036, JP 2010-186054, Japanese Patent Application Publication No. 2010-186056, Japanese Patent Application Publication No. 2010-275388, Japanese Patent Application Publication No. 2010-222586, Japanese Patent Application Publication No. 2010-084144, Japanese Patent Application Publication No. 2011-107199, Japanese Patent Application Publication No. 2011-236416, Japanese Patent Application The photobase generator described in 2011-080032 and other documents.

The above photobase generators may be used alone or in combination of two or more. The blending amount of the photobase generator in the thermosetting resin composition is preferably 1 to 50 with respect to 100 parts by mass of the heat-reactive compound. The part by mass, more preferably 1 to 40 parts by mass. When it is less than 1 part by mass, development may be difficult, which is not good.

[Maleimide compound]

The thermosetting resin composition of the present invention may contain a maleimide compound.

Examples of the maleimide compound include polyfunctional aliphatic / alicyclic maleimide and polyfunctional aromatic maleimide. A maleimide compound having more than two functions (multifunctional maleimide compound) is preferred. Multifunctional aliphatic / alicyclic maleimide, such as N, N'-methylenebismaleimide, N, N'-ethylidenebismaleimide, and ginseng ( Hydroxyethyl) trimer isocyanate and aliphatic / alicyclic maleimide carboxylic acid are dehydrated and esterified to obtain the trimide isocyanate skeleton of the maleimide compound; the ginseng (carbamate hexyl ) Trimeric isocyanate and aliphatic / cycloaliphatic maleimide alcohol are carbamate-derived to obtain a trimer isocyanate skeleton of the maleimide carbamate compound and other tripolyisocyanate Skeleton polymaleimide; isophorone biscarbamate bis (N-ethyl maleimide), triethylene glycol bis (maleimide ethyl carbonate), fat Dehydration esterification of aliphatic / alicyclic maleimide carboxylic acid and various aliphatic / alicyclic polyols, or aliphatic / alicyclic maleimide carboxylic acid ester and various aliphatic / alicyclic Aliphatic / alicyclic polymaleimide ester compounds obtained by transesterification of aliphatic polyols; aliphatic / alicyclic maleimide carboxylic acid and various aliphatic / alicyclic polycyclic Aliphatic / alicyclic polymaleimide compounds obtained by oxide ring-opening reaction; the aliphatic / alicyclic maleic Aliphatic / alicyclic polymaleimidocarbamate compounds obtained by carbamate reaction of imidate with various aliphatic / alicyclic polyisocyanates.

Multifunctional aromatic maleimide, dehydration esterification of maleimide carboxylic acid with various aromatic polyols, or transesterification of maleimide carboxylic acid ester with various aromatic polyols Aromatic polymaleimide compounds obtained by reaction; aromatic polymaleimide compounds obtained by ether ring-opening reaction of maleimide carboxylic acid with various aromatic polyepoxides Aromatic polymaleimide aminocarbamate compounds such as aromatic polymaleimide obtained by subjecting maleimide alcohol and various aromatic polyisocyanates to carbamate reaction Imines, etc.

Specific examples of the polyfunctional aromatic maleimide include, for example, N, N '-(4,4'-diphenylmethane) bismaleimide, N, N'-2,4-methan Phenylbismaleimide, N, N'-2,6-tolylphenylbismaleimide, 1-methyl-2,4-bismaleimidebenzene, N, N ' -m-phenylenebismaleimide, N, N'-P-phenylenebismaleimide, N, N'-m-stilbenebismaleimide, N, N '-4,4'-biphenylenebismaleimide, N, N'-4,4'-[3,3'-dimethyl-biphenylene] bismaleimide, N, N'-4,4 '-[3,3'-dimethyldiphenylmethane] bismaleimide, N, N'-4,4'-[3,3'-diethyl Diphenylmethane] bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4'-diphenylpropane bismaleimide Acetylimide, N, N'-4,4'-diphenyl ether bismaleimide, N, N'-3,3'-diphenyl bismaleimide, N, N ' -4,4'-diphenyl bisbismaleimide, 2,2-bis [4- (4-maleimidephenoxy) phenyl] Propane, 2,2-bis [3-t-butyl-4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3-s-butyl-4- ( 4-maleimidephenoxy) phenyl] propane, 1,1-bis [4- (4-maleimidephenoxy) phenyl] decane, 1,1-bis [2- Methyl-4- (4-maleimidephenoxy) -5-t-butylphenyl] -2-methylpropane, 4,4'-cyclohexylene-bis [1- (4- Maleimide phenoxy) -2- (1,1-dimethylethyl) benzene], 4,4'-methylene-bis [1- (4-maleimide phenoxy ) -2,6-bis (1,1-dimethylethyl) benzene], 4,4'-methylene-bis [1- (4-maleimidephenoxy) -2,6 -Di-s-butylbenzene], 4,4'-cyclohexylene-bis [1- (4-maleimidephenoxy) -2-cyclohexylbenzene, 4,4'-methylene Bis [1- (maleimidephenoxy) -2-nonylbenzene], 4,4 '-(1-methylethylene) -bis [1- (maleimidephenoxy) ) -2,6-bis (1,1-dimethylethyl) benzene], 4,4 '-(2-ethylhexylene) -bis [1- (maleimidephenoxy)- Benzene], 4,4 '-(1-methylheptylidene) -bis [1- (maleimidephenoxy) -benzene], 4,4'-cyclohexylene-bis [1- ( Maleimidephenoxy) -3-methylbenzene], 2,2-bis [4- (4-maleimidephenoxy) phenyl] hexafluoropropane, 2,2-bis [ 3-methyl-4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3-methyl-4- (4-maleimidephenoxy) benzene Group] Hexafluoropropane, 2,2-bis [3,5-dimethyl-4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3,5-di Methyl-4- (4-maleimidephenoxy) phenyl] hexafluoropropane, 2,2-bis [3-ethyl-4- (4-maleimidephenoxy) benzene Group] propane, 2,2-bis [3-ethyl-4- (4-maleimidephenoxy) phenyl] hexafluoropropane, bis [3-methyl- (4-maleimide Aminophenoxy) phenyl] methane, bis [3,5-dimethyl- (4-maleimidephenoxy) phenyl] methane, bis [3-ethyl- (4-maleimide Imine phenoxy) phenyl] methane, 3,8- Bis [4- (4-maleimidephenoxy) phenyl] -tricyclo [5.2.1.02,6] decane, 4,8-bis [4- (4-maleimidephenoxy) Yl) phenyl] -tricyclo [5.2.1.02,6] decane, 3,9-bis [4- (4-maleimidophenoxy) phenyl] -tricyclo [5.2.1.02,6 〕 Decane, 4,9-bis [4- (4-maleimidophenoxy) phenyl] -tricyclo [5.2.1.02,6] decane, 1,8-bis [4- (4 -Maleimide phenoxy) phenyl] menthane, 1,8-bis [3-methyl-4- (4-maleimide phenoxy) phenyl] menthane, 1,8 -Bis [3,5-dimethyl-4- (4-maleimidephenoxy) phenyl] menthane and the like.

The blending amount of the maleimide compound is preferably an equivalent ratio with the alkali-developable resin (maleimide group: alkali-developable group) of 1: 0.1 to 1:10, more preferably 1: 0.2 ~ 1: 5. With such a blending ratio, development becomes easy.

[Polymer resin]

In the thermosetting resin composition of the present invention, a well-known polymer resin can be blended for the purpose of improving the flexibility and dryness of the obtained cured product.

Examples of the polymer resin include cellulose-based, polyester-based, phenoxy resin-based, polyvinyl acetal-based, polyethylene butyral-based, polyamidoamine-based, polyamidoamide-imide-based binder polymers, Segment copolymers, elastomers, rubber particles, etc. The binder polymer may be used alone or in combination of two or more.

By blending a polymer resin, the melt viscosity of the thermosetting resin composition will increase, and when heated after exposure, the flow of the resin in the through hole portion can be suppressed Sex. As a result, a flat substrate with no recesses can be formed on the through hole.

The added amount of the polymer resin is preferably 50 parts by mass or less, more preferably 1 to 30 parts by mass, and particularly preferably 5 to 30 parts by mass with respect to 100 parts by mass of the heat-reactive compound. If the blending amount of the polymer resin exceeds 50 parts by mass, there is a fear that the resistance of the thermosetting resin composition to degumming slag will deteriorate, which is not good.

(Block copolymer)

Block copolymer refers to a copolymer in which two or more polymers with different properties are linked by a covalent bond to form a long-chain molecular structure.

The block copolymer used in the present invention is preferably an A-B-A or A-B-A 'type block copolymer. Among the ABA or AB-A 'type block copolymers, it is preferred that the B from the center is a soft block, the glass transition point Tg is low, preferably below 0 ° C, and both outer sides of A or A' are hard embedded In the segment, the Tg is high, and it is preferably composed of polymer units of 0 ° C or higher. The glass transition point Tg is measured by differential scanning calorimetry (DSC).

In addition, among ABA or AB-A 'type block copolymers, it is more preferable that A or A' is composed of polymer units having a Tg of 50 ° C or higher, and B is composed of polymer units having a Tg of -20 ° C or lower. Block copolymer.

In addition, among the ABA or AB-A 'type block copolymers, it is preferable that A or A' is a high compatibility with the above heat-reactive compound, and it is preferable that B is a low compatibility with the above-mentioned heat-reactive compound By. In this way, by being a block copolymer in which the blocks at both ends are compatible with the medium and the blocks at the center are incompatible with the medium, it can be considered that the specific structure is easily displayed in the medium.

As A or A ', it is preferable to contain polymethyl (meth) acrylate (PMMA), polystyrene (PS), etc., and it is preferable to contain poly n-butyl acrylate (PBA), polybutadiene ( PB) etc. as B. In addition, a part of the component A or A 'can be introduced into the medium phase described above as represented by styrene units, hydroxyl-containing units, carboxyl-containing units, epoxy-containing units, N-substituted acrylamide units, etc. The hydrophilic unit with excellent solubility further improves the compatibility.

In addition, as the block copolymer used in the present invention, a block copolymer of 3 yuan or more is preferred, and the block copolymer synthesized by the living polymerization method whose molecular structure is precisely controlled can obtain the effects of the present invention In terms of better. This is considered to be because the block copolymer synthesized by the living polymerization method has a narrow molecular weight distribution, and the characteristics of the respective units are clear. The molecular weight distribution (Mw / Mn) of the block copolymer used is preferably 3 or less, more preferably 2.5 or less, and even more preferably 2.0 or less.

The block copolymer containing the (meth) acrylate polymer block as described above can be obtained by the methods described in the specifications of Japanese Patent Laid-Open No. 2007-516326 and Japanese Patent Laid-Open No. 2005-515281. The alkoxyamine compound represented by any one of (1) to (4) can be suitably obtained by polymerizing Y units and then polymerizing X units after polymerizing Y units.

(In the formula, n represents 2, Z represents a divalent organic group, preferably 1,2-ethanedioxy, 1,3-propanedioxy, 1,4-butanedioxy, 1, 6-hexanedioxy, 1,3,5-ginseng (2-ethoxy) cyanuric acid, polyamine amines, such as polyethylamine, 1,3,5-ginseng (2-ethyl) (Amino group) cyanuric acid, polythioxy, phosphonate or polyphosphonate. Ar represents a divalent aromatic group).

The weight average molecular weight of the block copolymer is preferably in the range of 20,000 to 400,000, and more preferably in the range of 50,000 to 300,000. When the weight average molecular weight is less than 20,000, the intended toughness and flexibility effects cannot be obtained, and the adhesiveness when the thermosetting resin composition is dry-filmed or applied to the substrate and temporarily dried is not good. On the other hand, when the weight average molecular weight exceeds 400,000, the viscosity of the thermosetting resin composition becomes high, and the printability and processability may be significantly deteriorated. When the weight average molecular weight is 50,000 or more, an excellent effect can be obtained for the relief from external shock.

As the polymer resin, the block copolymer is excellent in crack resistance during cold and heat cycles, and can suppress warpage after curing, which is preferable. The block copolymer is particularly preferable because it can suppress depressions in the through holes and make a substrate with a flat surface. In addition, by combining with an inorganic filler, crack resistance at the time of cooling and heating cycle is further improved.

(Elastomer)

In the thermosetting resin composition of the present invention, an elastomer having a functional group may be added. By adding an elastomer having a functional group, it is expected that the coatability is improved and the strength of the coating film is also improved. In addition, polyester-based elastomers, polyurethane-based elastomers, polyester-urethane-based elastomers, polyamide-based elastomers, polyester-based elastomers, acrylic elastomers can be used , Olefin elastomer, etc. In addition, resins in which a part or all of epoxy groups of epoxy resins having various skeletons are modified with two-terminal carboxylic acid-modified butadiene-acrylonitrile rubber can also be used. In addition, epoxy-containing polybutadiene-based elastomers, acrylic resin-containing polybutadiene-based elastomers, hydroxyl-containing polybutadiene-based elastomers, hydroxyl-containing isoprene-based elastomers can also be used Elastomers, etc. In addition, these elastomers may be used alone or in combination of two or more.

(Rubber particles)

The rubber particles may be in the form of particles made of organic materials such as polymers having a cross-linked structure. For example, as a copolymer of acrylonitrile butadiene, crosslinked NBR copolymerizing acrylonitrile and butadiene Particles; copolymerized with carboxylic acids such as acrylonitrile, butadiene and acrylic acid; the so-called core-shell with cross-linked polybutadiene, cross-linked silicone rubber, or NBR as the core layer, and cross-linked acrylic resin as the shell layer Structured cross-linked rubber particles (also known as "core-shell rubber particles").

Among them, especially from the viewpoint of dispersion control and particle size stability It is preferably a cross-linked rubber particle with a core-shell structure; more preferably a cross-linked rubber with a core-shell structure using a cross-linked acrylic resin as the shell layer and a cross-linked polybutadiene or cross-linked silicone rubber as the core layer particle.

Cross-linked NBR particles refer to those in which acrylonitrile and butadiene are copolymerized and partially cross-linked at the stage of copolymerization to become particles. In addition, by copolymerizing carboxylic acids such as acrylic acid and methacrylic acid together, carboxylic acid modified crosslinked NBR particles can also be obtained.

The core-shell rubber particles of crosslinked butadiene rubber-crosslinked acrylic resin can be obtained by a two-stage polymerization method in which the butadiene particles are polymerized by emulsion polymerization, and then monomers such as acrylate and acrylic acid are added to continue the polymerization .

The core-shell rubber particles of the crosslinked silicone rubber-crosslinked acrylic resin can be obtained by a two-stage polymerization method in which the silicon particles are polymerized by emulsion polymerization, and then monomers such as acrylate and acrylic acid are added to continue the polymerization.

The size of the rubber particles is 1 μm or less in terms of primary average particle diameter, preferably 50 nm to 1 μm. When the primary average particle diameter exceeds 1 μm, the adhesive strength may be reduced, or the insulation reliability of fine wiring may be impaired. The "primary average particle diameter" mentioned here does not refer to the aggregated particle diameter, that is, the secondary particle diameter, but refers to the particle diameter of the single substance that has not been aggregated.

In addition, the primary average particle diameter can be obtained by measuring with a laser diffraction particle size distribution meter, for example.

The rubber particles as described above may be used alone or in combination of two or more.

The content of the rubber particles is preferably 50% by mass or more in the resin composition Lower and better is 1 ~ 30% by mass.

For example, commercially available products of carboxylic acid-modified acrylonitrile butadiene rubber particles include XER-91 manufactured by Japan Synthetic Rubber Co., Ltd. Examples of the core-shell particles of butadiene rubber-acrylic resin include PALOLOID EXL 2655 manufactured by Rohm and Haas Co., Ltd. or AC-3832 manufactured by GANZ Chemical Industry Co., Ltd. The core-shell rubber particles of the crosslinked silicone rubber-acrylic resin may include GENIOPERLP52 manufactured by Asahi Kasei Wacker Silicone Co., Ltd.

By using rubber particles, the crack resistance during cold and hot cycles can be improved.

[Inorganic filler]

The thermosetting resin composition system contains an inorganic filler. The inorganic filler is used for the purpose of suppressing curing shrinkage of the cured product of the thermosetting resin composition and improving characteristics such as adhesion and hardness. Examples of inorganic fillers include barium sulfate, amorphous silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, silicon nitride, and aluminum nitride. , Boron nitride, Neuburg Siliceous Earth, etc.

The average particle diameter (D50) of the inorganic filler is preferably 1 μm or less, more preferably 0.7 μm or less, and still more preferably 0.5 μm. When the average particle diameter exceeds 1 μm, the patterned layer system may be cloudy, which is not good. The lower limit of the average particle diameter (D50) of the inorganic filler is not particularly limited, and is, for example, 0.01 μm or more. Here, the average particle diameter (D50) means the average primary particle diameter.

The average particle size (D50) can be determined by laser diffraction / scattering method. When the average particle diameter is within the above range, the refractive index becomes close to the resin component and the penetration is improved, and the efficiency of generating alkali from the photobase generator due to light irradiation increases.

The difference in refractive index between the inorganic filler and the alkali-developable resin is preferably 0.3 or less. By setting the refractive index difference to 0.3 or less, light scattering can be suppressed and good deep hardening characteristics can be obtained. Here, the refractive index of the inorganic filler is preferably 1.4 or more and 1.8 or less. Furthermore, the refractive index of the inorganic filler can be measured in accordance with JIS K 7105.

The blending ratio of the inorganic filler is preferably 20% by mass or more and 80% by mass or less based on the total solid content of the thermosetting resin composition; more preferably 30% by mass or more and 80% by mass or less. When the blending ratio of the inorganic filler exceeds 80% by mass, the viscosity of the composition becomes high, the coating property may be reduced, or the cured product of the thermosetting resin composition becomes brittle.

When the content of the inorganic filler in the hardened composition is increased by radical reaction, the resolution will be reduced. In the present invention, the hardening reaction is caused by the generated alkali. When the content is increased, good resolution can also be maintained.

In addition, the specific gravity of the inorganic filler is preferably 3 or less, more preferably 2.8 or less, and still more preferably 2.5 or less. By setting the specific gravity of the inorganic filler to 3 or less, thermal expansion can be suppressed. Examples of inorganic fillers of 3 or less include silicon dioxide and aluminum hydroxide, and silicon dioxide is particularly preferred.

Examples of the shape of the inorganic filler include an indefinite shape, a needle shape, a disk shape, a scale, a spherical shape, and a hollow shape. Here, from the composition in a high ratio From the viewpoint of blending, it is preferably spherical. In addition, the inorganic filler system improves moisture resistance, so it is more preferably treated with a surface treatment agent such as a silane coupling agent.

In addition, by containing an inorganic filler, crack resistance during cold and hot cycles can be improved. By containing a large amount of inorganic fillers, warpage after curing can also be suppressed.

In the present invention, the thermal expansion coefficient (CTE) of the cured product is preferably 40 ppm or less, more preferably 30 ppm or less, and still more preferably 20 ppm or less.

[Organic solvents]

In the thermosetting resin composition of the present invention, an organic solvent can be used in order to prepare the resin composition or to adjust the viscosity for coating on the substrate or the carrier film.

Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, and petroleum-based solvents. Such an organic solvent may be used alone or as a mixture of two or more.

[Photopolymerizable monomer]

The thermosetting resin composition of the present invention may contain a photopolymerizable monomer within a range that does not hinder the effect of the present invention.

Photopolymerizable monomers include alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate , (Meth) acrylic acid 2-hydroxypropyl ester and other (meth) acrylic acid hydroxyalkyl esters; ethylene glycol, propylene glycol, diethylene glycol, dipropylene Mono- or di (meth) acrylates of alkylene oxide derivatives such as alcohols; hexanediol, trimethylolpropane, pentaerythritol, di-trimethylolpropane, dipentaerythritol, ginsylhydroxyethyl trimer Polyvalent (meth) acrylates of polyols such as isocyanate or such ethylene oxide or propylene oxide adducts; polyethoxy groups of phenoxyethyl (meth) acrylate and bisphenol A Ethylene oxide or propylene oxide adducts (meth) acrylates such as di (meth) acrylates; glycerin diglycidyl ether, trimethylolpropane triglycidyl ether , (Meth) acrylates of glycidyl ethers such as triglycidoxy isocyanate; and melamine (meth) acrylates.

The blending amount of the photopolymerizable monomer is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 15% by mass based on the solid content other than the solvent of the thermosetting resin composition. . When the blending amount of the photopolymerizable monomer exceeds 50% by mass, the curing shrinkage becomes large, so warpage may be increased. In addition, if the photopolymerizable monomer is derived from (meth) acrylate, it contains an ester bond. At this time, due to the slag removal treatment, hydrolysis of the ester bond may occur, so the electrical characteristics may be reduced.

(Any other ingredients)

The thermosetting resin composition of the present invention may further contain components such as mercapto compounds, adhesion promoters, colorants, antioxidants, and ultraviolet absorbers as needed.

In particular, in the present invention, even when the content of the coloring agent is increased, undercutting can be suppressed to form good viaholes and lines.

These can use what is known in the field of electronic materials. Also, the above hot The chemical resin composition may be blended with well-known and commonly used thickeners such as fine powdered silica, hydrotalcite, organic bentonite, and montmorillonite; polysiloxane-based, fluorine-based, polymer-based defoamers and / or Leveling agent; silane coupling agent; antirust agent and other well-known and commonly used additives.

In addition, it is also possible to blend known and commonly used thermosetting resins such as block isocyanate compounds, amine resins, benzoxazine resins, carbodiimide resins, cyclic carbonate compounds, and episulfide resins as heat Hardening ingredients.

Furthermore, by containing a phenol resin as an alkali-developable resin and an epoxy resin as a heat-reactive compound, Tg can be increased, and a resin composition that can obtain a hardened product excellent in HAST resistance can be obtained without depending on the softening point of the raw material. . In addition, in a photocurable resin composition that does not incorporate a photopolymerizable monomer (containing an ethylenically unsaturated group in the molecule and which contains a carboxyl group-containing resin as a main component), it is a low-molecular compound blended to promote photocuring In the case of the composition of compound), it can become a resin composition excellent in adhesiveness.

In the conventional photo-curable resin composition, in order to cause a photo-curing reaction at room temperature, as a result of the increase in the Tg of the resin composition during curing, the curing reaction may stop, and the Tg of the resin composition must be designed to be low . On the other hand, the alkali-developable thermosetting resin composition of the present invention has no limitation on the Tg before the curing reaction, and can be expected to have a high Tg. In addition, the alkali-developable thermosetting resin composition of the present invention can be expected to be cured without being hindered by oxygen.

The thermosetting resin composition of the present invention is useful for forming a pattern layer of a printed wiring board, and is particularly useful as a material for solder resists or interlayer insulating layers.

[Pattern formation method]

The pattern forming method suitable for using the thermosetting resin composition of the present invention includes the step (A) of forming a resin layer composed of the thermosetting resin composition on the base material, which is in the form of a negative pattern The step (B) of activating the photobase generator contained in the thermosetting resin composition by light irradiation to harden the light irradiated part, and removing the unirradiated part by alkali development to form a negative pattern layer Step (C).

By pattern-shaped light irradiation, alkali is generated in the light-irradiated portion of the thermosetting resin composition, whereby the light-irradiated portion can be hardened. After that, by developing with an alkaline aqueous solution, the unirradiated portion can be removed to form a negative pattern layer.

Here, in the present invention, it is preferable to have a step (B1) of heating the resin layer after the step (B). Thereby, the resin layer can be sufficiently cured, and further a pattern layer with excellent curing characteristics can be obtained.

[Step (A)]

The pattern forming method will be described with reference to FIG. 1. Step (A) is a step of forming a resin layer composed of a thermosetting resin composition on the base material. The method of forming the resin layer may be a method of coating and drying the liquid thermosetting resin composition on the substrate, or a method of stacking the thermosetting resin composition into a dry film on the substrate method.

The method of applying the thermosetting resin composition to the substrate may be a known method such as doctor blade coating method, lip coating method, comma coating method, and film coating method. Also, the drying method can be applied Known methods such as a hot air circulation type drying furnace, an IR furnace, a heating plate, a convection oven, etc., equipped with a heat source of a steam heating method, a method of contacting the hot air in the dryer in countercurrent, and a method of blowing the support body from a nozzle.

As the substrate, in addition to printed wiring substrates or flexible printed wiring substrates in which circuits are formed in advance, paper-phenol resin, paper-epoxy resin, glass cloth-epoxy resin, glass-poly Acetylene imide, glass cloth / nonwoven fabric-epoxy resin, glass cloth / paper-epoxy resin, synthetic fiber-epoxy resin, fluororesin. Polyethylene. PPO. All grades (FR-4 etc.) of copper-clad laminates, polyimide films, PET films, glass substrates, ceramic substrates, wafer substrates, etc. of composite materials such as cyanate esters.

[Step (B)]

The step (B) is a step of irradiating light with a negative pattern to activate the photobase generator contained in the thermosetting resin composition to harden the light irradiated portion. In the step (B), the alkali generated by the light irradiation section destabilizes the photobase generator and further generates alkali. By performing such chemical proliferation by alkali, it can be sufficiently hardened to the deep part of the light irradiation part.

As the light irradiation machine used for light irradiation, for example, a direct drawing device capable of irradiating laser light, lamp light, or LED light can be used. A negative mask can be used for the pattern-shaped light irradiation mask.

The active energy line is preferably laser light or scattered light with a maximum wavelength in the range of 350 to 410 nm. By setting the maximum wavelength in this range, the thermal reactivity of the thermosetting resin composition can be efficiently improved. As long as the laser light in this range is used, either gas laser or solid laser can be used. In addition, although the irradiation dose varies depending on the film thickness and the like, it can generally be in the range of 100 to 1500 mJ / cm ² , preferably 300 to 1500 mJ / cm ² .

For the direct drawing device, for example, those made by Japan Orbotech Co., Ltd. and Pentax Co., Ltd. can be used. Any device can be used as long as it emits laser light with a maximum wavelength of 350 to 410 nm.

[Step (B1)]

Step (B1) is to harden the light-irradiated portion by heating. Step (B1) can be hardened to the deep part by the alkali generated in step (B).

The heating temperature is preferably a temperature at which the light-irradiated portion in the thermosetting resin composition will be thermally cured, but the unirradiated portion will not be thermally cured.

For example, step (B1) is preferably lower than the heating start temperature or peak heating temperature of the unirradiated thermosetting resin composition, and lower than the heating start temperature or heating peak of the thermosetting resin composition after light irradiation Heat at a higher temperature. By heating in this way, only the light irradiation part can be selectively hardened.

Here, the heating temperature is, for example, 80 to 140 ° C. By setting the heating temperature to 80 ° C. or higher, the light irradiation portion can be sufficiently cured. On the other hand, by setting the heating temperature to 140 ° C. or lower, only the light irradiation section can be selectively cured. The heating time is, for example, 10 to 100 minutes. The heating method is the same as the drying method described above.

In addition, the non-irradiated portion does not generate alkali from the photobase generator, so thermal curing is suppressed.

[Step (C)]

Step (C) is a step of removing unirradiated portions by development to form a negative pattern layer. As the development method, known methods such as a dipping method, a shower method, a spray method, and a brush method can be used. In addition, as the developing solution, amines such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, ethanolamine, and aqueous solutions of tetramethylammonium hydroxide (TMAH) or the like can be used. Such a mixture.

[Step (D)]

The pattern forming method preferably further includes the step (D) of ultraviolet irradiation after the step (C). By further performing ultraviolet irradiation after the step (C), the photobase generator remaining unactivated during the light irradiation can be activated. The wavelength and irradiation amount (irradiation amount) of ultraviolet rays in the ultraviolet irradiation step (D) after the step (C) may be the same as or different from the step (B). The suitable irradiation dose (irradiation dose) is 150 ~ 2000mJ / cm ² .

[Step (E)]

The above pattern forming method preferably further includes a step (E) of thermal curing (post-curing) after step (C).

When step (D) and step (E) are performed together after step (C), step (E) is preferably performed after step (D).

Step (E) is to fully thermally harden the pattern layer by the base generated by the photobase generator in step (B), or step (B) and step (D). At the time point of step (E), the unirradiated part has been removed, so step (E) can be The shot thermosetting resin composition proceeds at a temperature higher than the starting temperature of the curing reaction. By this, the pattern layer can be sufficiently thermally hardened. The heating temperature is, for example, 160 ° C or higher.

[Step (F)]

The above pattern forming method may further include a laser processing step (F). Laser processing can form fine openings. For the laser, known lasers such as YAG laser, CO ₂ laser, and excimer laser can be used.

Step (F) is preferably performed after step (C), or when steps (D) and (E) are included, it is preferably performed after steps (D) and (E).

[Step (G)]

The pattern forming method of the present invention may further include a step (G) of removing glue residue after step (F).

Step (G) includes a slag swelling step for swelling the slag and making it easy to remove, a removing step for removing the slag, and neutralizing the sludge generated by the slag removal liquid used in the removing step And steps.

The swelling step is performed using an alkaline chemical solution such as sodium hydroxide, which makes it easier to remove the plastic residue caused by the chemical solution for removing the plastic residue.

In the removal step, an acidic chemical solution containing an oxidizing agent such as dichromic acid or permanganic acid is used to remove the glue residue.

In the neutralization step, an alkali chemical solution such as sodium hydroxide is used to reduce and remove the oxidant used in the removal step.

[Example]

Hereinafter, the present invention will be described in further detail with examples and comparative examples, but the present invention is not limited by these examples and comparative examples.

(Examples 1 to 19, Comparative Examples 1 to 4) <Preparation of alkali-developable thermosetting resin composition>

Following the blending described in Tables 1 to 3 below, the materials described in the Examples / Comparative Examples were blended and prepared by a mixer, and then kneaded with a 3-roll mill to prepare a thermosetting resin composition. Unless otherwise specified, the values in the table refer to parts by mass.

<Production of dry film>

As a carrier film, a thermosetting resin composition was applied on a PET film with a thickness of 38 μm using an applicator, and then dried at 90 ° C./30 min to produce a dry film. The thickness of the thermosetting resin composition is adjusted to about 20 μm after drying. After that, the resulting dry film is slit to a specified size.

<Overlay>

Prepare a printed wiring substrate with a copper thickness of 15 μm on both sides of the circuit, and use a MEC CZ-8100 pre-treated substrate to use a vacuum machine MVLP-500 from Mingji to laminate the printed wiring substrate. film. Condition-based laminated at a temperature of 80 ℃, pressure of 5kg / cm ² / 60sec performed.

<Evaluation of B-stage state (treatment when the substrate is formed)>

For Examples 1 to 19, the evaluation of the B-stage state (semi-hardened state) of the dry film was performed. Slit processing was performed to a specified size of the dry film on which the resulting thermosetting resin composition was formed, and the state of the dry film was confirmed by the following method.

(evaluation method)

○: After slit processing, cracking of resin layer and falling of resin were confirmed

△: After slit processing, cracking of resin layer or falling of resin was confirmed

<Evaluation of Depression on Through Hole>

As shown in FIG. 3, a two-sided printed wiring substrate with a thickness of 0.3 mm and copper plated through holes formed at intervals of 300 μm in diameter and 1 mm in pitch is prepared for pretreatment using MEC CZ-8100. After that, the dry film with a thickness of 50 μm produced by the method shown in the section for producing dry film was vacuum-laminated by MVLP-500 of Mingji Co., and the two sides of the printed wiring substrate formed with through holes were simultaneously laminated and dried. film. Condition-based laminated at a temperature of 80 ℃, carried out ² / 60sec pressure of 5kg / cm. After that, the base material provided with the thermosetting resin layer was light-irradiated with full-surface contact exposure using ORC HMW680GW (metal halide lamp, scattered light), both front and back. The light irradiation amount is set in the manner described in Tables 1 to 3 with reference to the peak heat generation temperature of DSC. Next, the substrate was erected under the temperature conditions described in Tables 1 to 3 for 60 to 80 minutes. Further, the ultraviolet irradiation device of the ORC company ultraviolet ray was irradiated with an energy of 1 J / cm ² , then stood up in a hot-air circulation drying furnace, and was hardened at 170 ° C./60 min to completely harden it. After that, the surface roughness measuring instrument SE-700 (manufactured by Kosaka Research Institute) was used to confirm the amount of depression in the through hole.

(evaluation method)

○: The maximum recessed part on the through hole is below 5μm

△: The maximum concave part on the through hole exceeds 5μm

<Evaluation of the formation of opening patterns>

The substrate provided with the resin layer obtained above was irradiated with light of ORC HMW680GW (metal halide lamp, scattered light) as a negative pattern with an opening design size of 100 μm. The amount of light irradiation is set with reference to the peak heat generation temperature of DSC as described in Tables 1 to 3 below. Next, under the temperature conditions described in Tables 1 to 3, heat treatment is performed for 60 to 80 minutes. After that, the substrate was immersed in a 3wt% TMAH / 5wt% ethanolamine mixed aqueous solution at 35 ° C for 3 minutes for development, and the evaluation of the developability and patterning was performed according to the following criteria. The results obtained are shown in Tables 1-3.

(evaluation method)

◎: Aqueous sodium carbonate is used instead of TMAH / 5wt% ethanolamine mixed aqueous solution, which can also be developed. There is no damage caused by the developer on the surface of the light-irradiated part, and no development residue can be seen in the non-irradiated part

○: There is no damage to the surface of the light-irradiated part by the developing solution, and no development residue can be seen in the non-irradiated part

×: Development residue was confirmed in the non-irradiated part. Or, the undeveloped portion cannot be developed.

××: The state where the light-irradiated part and the non-irradiated part are completely dissolved.

×××: The undercut is visible in the deep part of the opening

<Line pattern formation>

The substrate provided with the resin layer obtained above was irradiated with light of ORC HMW680GW (metal halide lamp, scattered light) into a negative pattern having a design value of line width / line distance = 100/100 μm. The amount of light irradiation is set with reference to the peak heat generation temperature of DSC as described in Tables 1 to 3 below. Next, heat treatment is performed for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. After that, the substrate was immersed in a 3wt% TMAH / 5wt% ethanolamine mixed aqueous solution at 35 ° C for 3 minutes for development, and the obtained linear pattern with a design value of 100 μm was evaluated according to the following criteria. The results obtained are shown in Tables 1-3.

(evaluation method)

○: The top length of the line is 100 μm and the bottom length is 100 μm, and a pattern as designed is obtained.

△: The length of the top of the thread is 100 μm, the length of the bottom is 60 μm or more and less than 100 μm, and very little undercut is seen.

×: The length of the top of the thread is 100 μm, and the length of the bottom is less than 60 μm. A large undercut is seen at the bottom.

(Dress removal resistance)

For the substrate produced by the same method as the substrate for evaluating the opening pattern, the ultraviolet irradiation device of the ORC company ultraviolet irradiation device was used with an energy of 1 J / cm ² , and then the hot air circulation type drying furnace was shown in Tables 1 to 3 After the description, the curing temperature is cured for 60 minutes (post-curing). After that, laser processing is performed on the light irradiation surface. The light source was processed with CO ₂ laser (Hitachi Via Mechanics, light source 10.6 μm). Follow the benchmark evaluation below. In order to judge the pros and cons of workability, laser processing was performed under the same conditions.

The machining diameter target is 65 μm at the top end and 50 μm at the bottom end.

Condition: Hole (mask diameter): 3.1mm / Pulse width 20μsec / Output 2W / Frequency 5kHz / Number of firings: Burst 3 shots

For this substrate, which has been laser-processed, further degumming treatment is carried out by an aqueous solution of permanganic acid degumming residue (wet method). As an evaluation of the resistance to scum removal, the surface roughness of the substrate surface and the evaluation of the surrounding state of the laser opening were evaluated in accordance with the following criteria. The surface roughness was confirmed by measuring each surface roughness Ra with a laser microscope VK-8500 (Keyence Corporation, measurement magnification 2000 times, measurement pitch in the Z-axis direction 10 nm). The observation of the laser opening is performed by an optical microscope.

About liquid medicine (Rohm and Haas)

Swelling MLB-211 temperature 80 ℃ / time 10min

Permanganic acid MLB-213 temperature 80 ℃ / time 15min

Reduction MLB-216 temperature 50 ℃ / time 5min

About the evaluation method

◎: The surface roughness Ra after permanganic acid slag removal is less than 0.1 μm, and the difference from the processed diameter after laser processing is 2 μm or less

○: The surface roughness Ra after permanganic acid slag removal is 0.1 ~ 0.3μm The difference between the lower and the processing diameter after laser processing is 2 ~ 5μm

×: The surface roughness Ra after permanganic acid degumming slag exceeds 0.3 μm, and the difference from the processing diameter after laser processing is 5 μm or more

<Warpage evaluation after hardening>

Using a vacuum laminator MVLP-500 from Mingji Co., Ltd., a dry film with a thickness of 20 μm produced by the method shown in the paragraph for making a dry film was laminated on the glossy surface of a 18 μm copper foil cut into a square of 50 mm × 50 mm. One-sided. Condition-based laminated at a temperature of 80 ℃, carried out ² / 60sec pressure of 5kg / cm. Then, the copper foil provided with the thermosetting resin layer was light-irradiated using the whole surface contact exposure using ORC Corporation HMW680GW (metal halide lamp, scattered light). The amount of light exposure is set with reference to the peak heat generation temperature of DSC as described in Tables 1 to 3. Next, the substrate is heat-treated for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. Further, using an ultraviolet irradiation device of ORC Corporation, ultraviolet irradiation was performed with an energy of 1 J / cm ² , followed by curing in a hot air circulating drying oven at 170 ° C./60 min to obtain a copper foil provided with a thermosetting resin composition on one side. After that, the amount of warpage at the end 4 was measured with a vernier caliper, and used as an evaluation of the warpage state of the resulting hardened product.

(evaluation method)

◎: Warpage is hardly seen. The warpage of the largest warped part of 4 ends is less than 5mm

○: Very little warpage was seen. The warpage of the largest warped part of the four ends is more than 5mm and less than 20mm

△: The warpage amount of the largest warped part in the four ends is 20 mm or more

×: The hardened product shrinks in a cylindrical shape. Unable to measure the amount of warpage at the end with a vernier caliper

<CTE measurement>

According to the method described in the dry film production project, dry films with a thickness of 40 μm each were produced. Then, on the shiny side of the 18 μm copper foil, the dry film was laminated using a vacuum laminator MVLP-500 from Mingji Corporation. Condition-based laminated at a temperature of 80 ℃, carried out ² / 60sec pressure of 5kg / cm. After that, full-surface contact exposure was performed with HMW680GW (metal halide lamp, scattered light) of ORC Corporation. The amount of light irradiation is set with reference to the peak heat generation temperature of DSC as described in Tables 1 to 3 below. Next, heat treatment is performed for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. After that, ultraviolet irradiation was performed with an energy of 1 J / cm ² using an ultraviolet irradiation device of ORC Corporation, followed by complete curing at 170 ° C./60 min in a hot-air circulation drying oven. After that, the copper foil was peeled off to obtain an example. The resin composition described in the comparative example. After that, the obtained resin composition was cut into strips with a width of 3 mm and a length of 10 mm, and evaluated by CTE measurement (coefficient of thermal expansion) according to the TMA method (tensile method) described in JIS-C-6481. The heating rate was 5 ° C / min, and the thermal expansion coefficient below Tg was evaluated. The coefficient of thermal expansion is the average coefficient of thermal expansion from a temperature range of 25 ° C to 100 ° C in ppm.

The CTE values obtained by each are shown in Tables 1-3.

<Assessment of cold and heat cycle characteristics>

For printed wiring boards that have been treated with permanganic acid slag removal as described above, Further, using a commercially available electroless nickel plating bath and electroless gold plating bath, plating was performed under the conditions of nickel 0.5 μm and gold plating 0.03 μm, and the pattern layer was subjected to gold plating. The obtained printed wiring board was evaluated for the thermal cycle characteristics. The treatment conditions were -65 ℃ 30min, 150 ℃ 30min as one cycle, after 2000 cycles of heat application, the state of the surface and the peripheral part of the pattern layer was observed with an optical microscope, and the cracks were evaluated in accordance with the following criteria. The number of observation patterns is 100 holes. The results obtained are shown in Tables 1 to 3 below.

(evaluation method)

◎ ○: No cracks occurred on the surface and peripheral parts of the pattern layer

◎: The occurrence rate of cracks on the periphery of the pattern layer is less than 10%

○: The occurrence rate of cracks on the periphery of the pattern layer is more than 10% and less than 30%

△: The occurrence rate of cracks in the peripheral part of the pattern layer is more than 30%

<Measurement method of refractive index of heat-reactive compound, maleimide compound, and alkali-developable resin>

Measuring device: Abbe refractometer

Measurement conditions: wavelength 589.3nm, temperature 25 ℃

(Thermosetting compound + alkali-developable resin + photobase generator + filler)

(+ Polymer resin)

(Comparative example)

The components in Tables 1 to 3 are as follows.

(Thermally reactive compound)

※ 828: Bis-A liquid epoxy resin (equivalent to 190g / eq), Mitsubishi Chemical Corporation

※ HP-4032: naphthol epoxy resin (equivalent to 150g / eq), DIC Corporation

※ HP-7200 H60: dicyclopentadiene epoxy resin (equivalent 265g / eq), DIC Corporation dissolved with cyclohexanone. Solid content 60%

(Maleimide compound)

※ UVT-302: acrylic polymer with maleimide group on the side chain (equivalent to 320g / eq), East Asia Synthetic Corporation

(Alkali developing resin)

※ HF-1M H60: Dissolve phenol novolak (hydroxyl equivalent 105g / eq), Minghe Chemical Co., Ltd. with cyclohexanone. Solid content 60%

MEH-7851M H60: Biphenyl / phenol novolac (hydroxyl equivalent 210g / eq), Minghe Chemical Co., Ltd., dissolved in cyclohexanone. Solid content 60%.

※ Joncryl 586 H60: dissolve styrene acrylic copolymer resin, Mw = 3100, solid component acid value = 108mgKOH / g, Johnson Polymer with cyclohexanone. Solid content 60%

※ Joncryl 68 H60: styrene acrylic copolymer resin, Mw = 10000, acid value 195mgKOH / g, Johnson Polymer

(Photobase generator)

※ Irg369: 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl) -butanone-1, BASF JAPAN

※ WPBG-140: 1- (anthraquinone-2-yl) ethylimidazole carboxylate, Wako Pure Chemical Industries

(Polymer resin)

※ YX8100 BH30: phenoxy resin. Mitsubishi Chemical Corporation. Solid content 30%

(Inorganic filler)

※ SO-C2: spherical silicon dioxide D50 = 0.5μm, refractive index = 1.4 ~ 1.5, Admatechs, specific gravity: 2.2g / cm ³

※ AO-502: spherical alumina D50 = 0.7μm, refractive index = 1.76, Admatechs, specific gravity: 3.9g / cm ³

※ Higilite H-42M: aluminum hydroxide D50 = 1.0μm, refractive index = 1.65, Showa Denko Corporation, specific gravity: 2.4g / cm ³

※ B-30: Barium sulfate, D50 = 0.3μm, refractive index = 1.64, Sakai Chemical Company, specific gravity: 4.3g / cm ³

(other)

※ R-2000: cresol novolac, acrylic acid, THPA modified resin (solid content 61%, solid component acid value 87mgKOH / g, DIC Corporation)

※ DPHA: dipentaerythritol hexaacrylate_Japan Chemicals

※ IRG-184: 1-hydroxycyclohexyl-phenyl ketone_Ciba Japan

As shown in Tables 1 to 3, in Examples 1 to 19, it can be confirmed that patterns can be formed by alkali development, and the obtained patterns have excellent hardening characteristics and cold-heat cycle characteristics.

In addition, in Examples 15, 16, etc., by blending a polymer resin, the melt viscosity of the thermosetting resin composition increases, and upon heating after exposure, The fluidity of the resin in the through-hole portion can be suppressed. As a result, a flat substrate in which no depression is seen in the through hole can be produced.

In addition, in Examples 18 and 19, even when the content of the inorganic filler is relatively large, good hardenability can be obtained during cooling and heating cycles.

On the other hand, in the photo-radical composition of Comparative Example 4, it is difficult to form a pattern by alkali development. In addition, the line shape is also bad. Furthermore, the warpage after hardening is also large, and the hardenability during cold and hot cycles is also poor.

<DSC measurement immediately after light irradiation>

The substrate provided with the resin layer obtained in Example 1 was irradiated with light of a negative pattern by HMW680GW (metal halide lamp, scattered light) of ORC Corporation. Each substrate was irradiated with pattern light at an irradiation amount of 1000 mJ / cm ² . After light irradiation, the resin layer was cut from the substrate, and immediately heated with Seiko Instruments DSC-6200 at a heating rate of 5 ° C / min from 30 to 300 ° C. DSC measurement was performed on the light-irradiated portion and the non-irradiated portion, respectively. In addition, the hardened layer composed of the thermosetting resin composition immediately after ultraviolet irradiation and before post-curing was also subjected to DSC measurement.

FIG 2 is a system non-irradiated portion, the irradiation amount of 1000mJ / cm light irradiating unit ² irradiation amount of 1000 mJ / cm ² irradiated with the light irradiation portion is further light DSC rear of 1000mJ / cm ² UV irradiation line in FIG. In the light irradiation part of Example 1, the peak was shifted toward the low temperature side by light irradiation.

(Comparative example 5)

Prepare a printed wiring substrate with a thickness of 0.4 mm and a circuit board thickness of 0.4 mm on a copper thickness of 15 μm, and perform pre-treatment using MEC CZ-8100. After that, the trade name PSR-4000G23K (Sun Ink Manufacturing Co., Ltd., a photo-curable resin composition containing an alkali-developable resin having an acrylic epoxy ester structure) was screen-printed to become 20 μm after drying Carry out coating. Next, after drying in a hot-air circulation drying oven at 80 ° C./30 min, ORC HMW680GW (metal halide lamp, scattered light) was irradiated with a light of 300 mJ / cm ² into a negative pattern. After that, it was developed with a 1 wt% sodium carbonate aqueous solution for 60 seconds, and then subjected to a heat treatment at 150 ° C / 60 min using a hot air circulation drying furnace to obtain a pattern-shaped cured coating film.

Thereafter, the evaluation of the resistance to dross removal was conducted in the same manner as in Example 2 above. As a result, the slag removal resistance was "×".

Claims (5)

A pattern forming method, which includes a step (A) of forming a resin layer composed of a thermosetting resin composition, a step (B) and a step (B) of a pattern in which the light irradiation of the resin layer is negative ), After the step (B1) of heating the resin layer and the step (B1), the non-irradiated portion is removed by alkali development to form a pattern forming method of the step (C) of forming a negative pattern layer, It is characterized in that the aforementioned thermosetting resin composition contains an alkali-developable resin, a heat-reactive compound, an inorganic filler, and a photobase generator, and this method is used in an unirradiated state, even if heated to 80 to 140 ° C It does not harden, but by selective light irradiation and heating after light irradiation, the alkali-developable resin and the heat-reactive compound undergo an addition reaction, whereby alkali development can be used to form a negative pattern Alkali-developable thermosetting resin composition. An alkali-developable thermosetting resin composition is used in the pattern forming method as described in item 1 of the patent application. For example, the alkali-developable thermosetting resin composition according to item 2 of the patent application, wherein the average particle diameter of the inorganic filler is 1 μm or less. For example, the alkali-developable thermosetting resin composition according to item 2 or 3 of the patent application scope will generate a heat peak in the DSC measurement by light irradiation; or, the alkali-developing thermosetting property after light irradiation The heat-onset temperature of the resin composition in the DSC measurement is lower than the heat-onset temperature of the non-irradiated alkali-developing thermosetting resin composition in the DSC measurement; or, the alkali-developing thermosetting property after light irradiation The peak heat generation temperature of the resin composition in the DSC measurement is lower than the peak heat generation temperature of the non-irradiated alkali-developing thermosetting resin composition in the DSC measurement. A printed wiring board is characterized by having a patterned layer composed of an alkali-developable thermosetting resin composition according to any one of claims 2 to 4.