KR102114104B1 - Alkali-developable thermosetting resin composition, and printed wiring board - Google Patents

Abstract

An object of the present invention is to provide an alkali developing type thermosetting resin composition and a printed wiring board capable of forming a pattern layer by development even when the inorganic filler is highly charged. Further, an object of the present invention is to provide an alkali developing type thermosetting resin composition and a printed wiring board capable of forming a pattern layer excellent in cold / heat cycle characteristics. An alkali-developable resin, a heat-reactive compound, an inorganic filler, and a photobase generator are included, and the alkali-developable resin and the heat-reactive compound are additionally reacted by selective light irradiation, thereby forming a negative pattern by alkali development. It is an alkali-developable thermosetting resin composition characterized in that this becomes possible.

Description

Alkali-developed thermosetting resin composition, printed wiring board {ALKALI-DEVELOPABLE THERMOSETTING RESIN COMPOSITION, AND PRINTED WIRING BOARD}

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

In recent years, as a material of a solder resist for a printed wiring board or a flexible printed wiring board, an alkali developing type photocurable resin composition using an aqueous alkali solution as a developer has been mainstream in consideration of environmental problems. As the alkali-developable photocurable resin composition, as described in Patent Documents 1 and 2, an epoxy acrylate-modified resin (hereinafter, sometimes referred to as an epoxy acrylate) derived by modification of the epoxy resin is included. The resin composition to be used is generally used.

As a method of forming a solder resist using such a photocurable resin composition, a photocurable resin composition is applied to a substrate and dried to form a resin layer, and the resin layer is irradiated with a pattern in a pattern, and then developed with an alkali developer. There is a method of forming a predetermined pattern.

Moreover, a printed wiring board and a flexible printed wiring board are mounted and used for various apparatuses. Therefore, it is required to be resistant to sudden changes in the environment such as temperature. Therefore, high temperature change resistance is also required for the solder resist, but when the difference in the coefficient of linear expansion (CTE) between the thermosetting resin and the substrate forming material such as the substrate, copper, and underfill is large, the resist in the TCT (thermal cycle test) is used. There is a problem that cracking occurs.

On the other hand, it has been widely used in recent years to match the CTE of the thermosetting resin with the CTE of the peripheral member material. For example, it is common to reduce CTE and suppress curing shrinkage by high-filling the inorganic filler in a thermosetting resin.

Japanese Patent Laid-Open No. 61-243869 (patent claim) Japanese Patent Laid-Open No. 3-250012 (Patent Claims)

However, when the inorganic filler is highly charged in the thermosetting resin composition, light is prevented from being transmitted to the deep portion. In that case, there was a problem that it was difficult to form a pattern layer because resolution was not obtained.

Accordingly, an object of the present invention is to provide an alkali developing type thermosetting resin composition and a printed wiring board capable of forming a pattern layer by developing even when the inorganic filler is highly charged. Another object of the present invention is to provide an alkali developing type thermosetting resin composition and a printed wiring board capable of forming a pattern layer having excellent cold / heat cycle characteristics.

As a result of earnest examination to solve the above-mentioned problems, the present inventors found that the above-mentioned problems can be solved by setting the following configuration, and have come to complete the present invention.

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

It is preferable that the average particle diameter of the said inorganic filler is 1 micrometer or less in the alkali-developable thermosetting resin composition of this invention.

Moreover, it is preferable that the refractive index difference of the said inorganic filler and resin is 0.3 or less in the alkali-developable thermosetting resin composition of this invention.

Moreover, it is preferable that the refractive index of the said inorganic filler is 1.45 or more and 1.65 or less of the alkali-developable thermosetting resin composition of this invention.

In addition, the alkali developing type thermosetting resin composition of the present invention generates an exothermic peak in DSC measurement by light irradiation, or the exothermic initiation temperature in DSC measurement of the light developing alkali developing type thermosetting resin composition is unirradiated. The exothermic peak temperature in DSC measurement of the alkali-developing type thermosetting resin composition is lower than the exothermic initiation temperature in DSC measurement, or the light-radiated alkali developing type thermosetting resin composition has an unirradiated alkali developing type thermosetting resin composition. It is preferable that it is lower than the exothermic peak temperature in DSC measurement of.

ADVANTAGE OF THE INVENTION According to this invention, the alkali developing type thermosetting resin composition which can form a pattern layer by image development, and a printed wiring board can be provided. In addition, according to the present invention, it is possible to provide an alkali developing type thermosetting resin composition and a printed wiring board capable of forming a pattern layer excellent in curability and cold heat cycle characteristics.

1 is a schematic diagram showing an example of a pattern forming method using the alkali developing type thermosetting resin composition of the present invention.
It is a figure which shows the DSC chart about the resin layer containing the alkali-developable thermosetting resin composition of Example 1 of this invention.
3 is a cross-sectional view of a double-sided printed wiring substrate for explaining evaluation of a recess on a through hole.

The alkali developable thermosetting resin composition of the present invention (hereinafter sometimes referred to as "thermosetting resin composition") includes an alkali developable resin, a heat-reactive compound, an inorganic filler, and a photobase generator, and is optional It is characterized in that, by irradiation of light, the alkali-developable resin and the heat-reactive compound are reacted additionally, thereby forming a negative pattern by alkali development. Here, pattern formation means forming a patterned cured product, that is, a pattern layer.

In the resin layer containing the thermosetting resin composition, base is generated on the surface by light irradiation. Then, the photobase generator is destabilized by the generated base, and it is thought that the base further chemically proliferates to the deep portion. Here, since the base acts as a catalyst for the addition reaction of the alkali developable resin and the heat-reactive compound, the addition reaction proceeds to the deep portion, so that the resin layer hardens to the deep portion in the light irradiation portion.

Therefore, even when the inorganic filler is highly charged, the light-curable resin composition is irradiated in a pattern shape, and then alkali-developed to remove the unirradiated portion to easily form the pattern layer.

In addition, in the thermosetting resin composition of the present invention, the alkali developable resin and the heat-reactive compound are cured by an addition reaction, so that a pattern layer with less deformation or curing shrinkage than the photocurable resin composition can be obtained.

The thermosetting resin composition may not be cured even when heated in an unirradiated state, and may be a composition that can be cured by heat by irradiating with light.

In the thermosetting resin composition of the present invention, an exothermic peak is generated in DSC measurement by light irradiation, or the exothermic initiation temperature in DSC measurement of a light-cured thermosetting resin composition in DSC measurement of an unirradiated thermosetting resin composition It is preferable that the exothermic peak temperature in DSC measurement of the thermosetting resin composition irradiated with light lower than the exothermic initiation temperature is lower than the exothermic peak temperature in DSC measurement of the unirradiated thermosetting resin composition.

In addition, the thermosetting resin composition of the present invention, the temperature difference (also referred to as ΔT start) of the exothermic start temperature in DSC measurement between the light-cured thermosetting resin composition and the unirradiated thermosetting resin composition or the temperature difference of the exothermic peak temperature (ΔT peak Also referred to as) is preferably 10 ° C or higher, more preferably 20 ° C or higher, and even more preferably 30 ° C or higher.

Here, ΔT start means that a thermosetting resin composition of the same composition is prepared, one is irradiated with light, and the other is irradiated with light, and DSC (differential scanning calorimetry) measurement is performed, respectively, and light irradiated It indicates the temperature difference between the exothermic onset temperature indicating the initiation of the curing reaction of the composition and the exothermic onset temperature of the unirradiated resin composition. ΔT peak is the temperature difference between the exothermic peak temperature of the resin composition of light irradiation and unirradiation when DSC measurement is similarly performed.

In addition, the irradiation amount in DSC measurement of the thermosetting resin composition irradiated with light is the irradiation amount which raises the irradiation amount, and the shift of the exothermic peak temperature by light irradiation of the thermosetting resin composition does not occur (saturation).

When the ΔT start or ΔT peak is 10 ° C. or more, the occurrence of so-called erosion in which the unirradiated portion remains due to the alkali phenomenon or the light irradiated portion removed by the alkali phenomenon can be suppressed. Moreover, when ΔT start or ΔT peak is 10 ° C. or more, it is possible to take a wide range of heating temperatures that can be taken in the heating step (B1) described later.

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

[Alkaline developing resin]

The alkali-developable resin is a resin containing at least one functional group among phenolic hydroxyl groups, thiol groups and carboxyl groups, and is developable with an alkali solution, preferably a compound having two or more phenolic hydroxyl groups, carboxyl group-containing resins, phenolic And compounds having two or more thiol groups and compounds having a hydroxyl group and a carboxyl group.

Examples of the compound having two or more phenolic hydroxyl groups include phenol novolak resin, alkylphenol novolak resin, bisphenol A novolak resin, dicyclopentadiene type phenol resin, Xylok type phenol resin, terpene modified phenol resin, And conventionally known phenol resins such as polyvinylphenols, bisphenol F, bisphenol S type phenol resins, poly-p-hydroxystyrene, condensates of naphthol and aldehydes, and condensates of dihydroxynaphthalene and aldehydes.

In addition, as a phenol resin, a compound having a biphenyl skeleton or a phenylene skeleton, or both skeletons, and a phenolic hydroxyl group-containing compound, phenol, orthocresol, paracresol, metacresol, 2,3-xyllenol, 2 , 4-Xylenol, 2,5-Xylenol, 2,6-Xylenol, 3,4-Xylenol, 3,5-Xylenol, Catechol, Resorcinol, Hydroquinone, Methylhydroquinone , 2,6-dimethylhydroquinone, trimethylhydroquinone, pyrogallol, phloroglucinol, and the like, and a phenol resin having various skeletons may be used.

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

As the carboxyl group-containing resin, a resin containing a known carboxyl group can be used. The presence of a carboxyl group can make the resin composition alkali developable. In addition, although a compound having an ethylenically unsaturated bond in the molecule may be used in addition to the carboxyl group, in the present invention, as the carboxyl group-containing resin, for example, the number of carboxyl groups not having an ethylenically unsaturated double bond as shown in (1) below It is preferred to use only.

As specific examples of the carboxyl group-containing resin that can be used in the present invention, there may be mentioned compounds (any of oligomers and polymers) as listed below.

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid with an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, and isobutylene. In addition, lower alkyl refers to an alkyl group having 1 to 5 carbon atoms.

(2) Diisocyanates such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, and carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, and polycarbonate-based polyols and polyethers Contains polyvalent polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A-based alkylene oxide adduct diols, phenolic hydroxyl groups, and compounds having diol compounds such as compounds having an alcoholic hydroxyl group by a polyaddition reaction. Urethane resin.

(3) Diisocyanate compounds such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, and polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, polyolefin-based polyols, acrylic polyols , A terminal carboxyl group-containing urethane resin formed by reacting an acid anhydride at the end of a urethane resin by a polyaddition reaction of a diol compound such as a bisphenol A-based alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group .

(4) Diisocyanate, bifunctional epoxy resins such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, and biphenol type epoxy resin. (Meth) acrylate or a partial acid anhydride modified product thereof, a carboxyl group-containing urethane resin by a polyaddition reaction of a carboxyl group-containing dialcohol compound and a diol compound.

(5) During the synthesis of the resin of (2) or (4), a compound having one hydroxyl group and one or more (meth) acryloyl groups is added to a molecule such as hydroxyalkyl (meth) acrylate to terminate ( (Meth) acrylated carboxyl group-containing urethane resin.

(6) During the synthesis of the resin of (2) or (4), having one isocyanate group and one or more (meth) acryloyl groups in the molecule, such as an equimolar reactant of isophorone diisocyanate and pentaerythritol triacrylate A carboxyl group-containing urethane resin obtained by adding a compound to a terminal (meth) acrylate.

(7) An unsaturated monocarboxylic acid such as (meth) acrylic acid is reacted with the polyfunctional (solid) epoxy resin as described above, such as phthalic anhydride, tetrahydro phthalic anhydride, hexahydro phthalic anhydride, etc. A carboxyl group-containing resin to which dibasic acid anhydride is added.

(8) By reacting a saturated monocarboxylic acid with a polyfunctional (solid) epoxy resin as described above, dibasic acid anhydrides such as phthalic anhydride, tetrahydro phthalic anhydride and hexahydro phthalic anhydride are added to the hydroxyl group present in the side chain. The carboxyl group-containing resin.

(9) A carboxyl group-containing resin obtained by reacting (meth) acrylic acid with a polyfunctional epoxy resin epoxidized with epichlorohydrin, and also adding a dibasic acid anhydride to the resulting hydroxyl group.

(10) A carboxyl group-containing polyester resin in which a dicarboxylic acid is reacted with a polyfunctional oxetane resin as described below, and dibasic acid anhydride is added to the generated primary hydroxyl group.

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

(12) Saturated monocarboxylic acid is reacted with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide, and polybasic acid anhydride is added to the reaction product obtained. A carboxyl group-containing resin obtained by reacting.

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

(14) Saturated monocarboxylic acid is reacted with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule and a cyclic carbonate compound such as ethylene carbonate and propylene carbonate, and the reaction product obtained Carboxyl group-containing resin obtained by reacting polybasic acid anhydride with.

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

(16) An unsaturated group-containing monocarboxylic acid is reacted with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule and a cyclic carbonate compound such as ethylene carbonate and propylene carbonate, and is obtained. A carboxyl group-containing resin obtained by reacting a polybasic acid anhydride with a reaction product.

(17) A compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol and a saturated monocarboxylic acid are reacted with an epoxy compound having a plurality of epoxy groups in one molecule. A carboxyl group-containing resin obtained by reacting an alcoholic hydroxyl group of the obtained reaction product with polybasic acid anhydrides such as maleic anhydride, tetrahydro phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic acid.

(18) A compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol is reacted with an epoxy compound having a plurality of epoxy groups in one molecule, and alcoholicity of the obtained reaction product A carboxyl group-containing resin obtained by reacting a hydroxyl group with polybasic anhydride such as maleic anhydride, tetrahydro phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic acid.

(19) Compounds having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, such as p-hydroxyphenethyl alcohol, and an unsaturated compound such as (meth) acrylic acid, to an epoxy compound having a plurality of epoxy groups in one molecule Contains carboxyl groups obtained by reacting a group-containing monocarboxylic acid and reacting polybasic acid anhydrides such as maleic anhydride, tetrahydro phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic acid with respect to the alcoholic hydroxyl group of the obtained reaction product. Suzy.

(20) One epoxy group and at least one (meth) in a molecule such as glycidyl (meth) acrylate or α-methylglycidyl (meth) acrylate to any one of the resins (1) to (19). ) A carboxyl group-containing resin obtained by further adding a compound having an acryloyl group.

Since the alkali-developable resin as described above has a large number of carboxyl groups, hydroxy groups, and the like on the side chain of the backbone polymer, development with an aqueous alkali solution becomes possible.

In addition, the hydroxyl group equivalent or carboxyl group equivalent of the carboxyl group-containing resin is preferably 80 to 900 g / eq., More preferably 100 to 700 g / eq. When the hydroxyl group equivalent or carboxyl group equivalent exceeds 900 g / eq., Adhesion of the pattern layer may not be obtained, or alkali development may be difficult. On the other hand, hydroxyl group equivalent or carboxyl group equivalent is 80 g / eq. In the case of less than, since the dissolution of the light irradiation part by the developer proceeds, the line becomes thinner than necessary, or in some cases, it is difficult to draw a normal resist pattern by dissolving and peeling with the developer without discrimination between the light irradiation part and the non-irradiation part. It is not preferable because it may become dark. Moreover, when a carboxyl group equivalent or a phenol group equivalent is large, even if content of alkali developable resin is small, it is preferable because image development becomes possible.

Moreover, although the weight average molecular weight of the alkali developable resin used by this invention differs depending on a resin skeleton, the range of 2,000-150,000, furthermore 5,000-100,000 is preferable. If the weight average molecular weight is less than 2,000, the adhesion-free performance may be poor, the moisture resistance of the resin layer after light irradiation may be poor, film reduction may occur during development, and resolution may be greatly deteriorated. On the other hand, when the weight average molecular weight exceeds 150,000, developability may deteriorate significantly, and storage stability may be deteriorated.

In the present specification, (meth) acrylate is a generic term for acrylates, methacrylates, and mixtures thereof, and the same applies to other similar expressions.

As the compound having a thiol group, for example, trimethylolpropane tristhiopropionate, pentaerythritol tetrakisthiopropionate, ethylene glycol bisthioglycolate, 1,4-butanediol bisthioglycolate, trimethylolpropane tristhio Glycolate, pentaerythritol tetrakisthioglycolate, di (2-mercaptoethyl) ether, 1,4-butanedithiol, 1,3,5-trimercaptomethylbenzene, 1,3,5-trimercaptomethyl -2,4,6-trimethylbenzene, terminal thiol group-containing polyether, terminal thiol group-containing polythioether, thiol compound obtained by reaction of an epoxy compound with hydrogen sulfide, obtained by reaction of a polythiol compound with an epoxy compound And thiol compounds having terminal thiol groups.

It is preferable that the alkali developable resin is a compound having a carboxyl group-containing resin or a phenolic hydroxyl group. Moreover, it is preferable that alkali developable resin is non-photosensitive which 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 an epoxy acrylate, it has high resistance to a desmear solution. Therefore, a pattern layer excellent in curing properties can be formed. Moreover, since it does not have a photocurable structure, hardening shrinkage can be suppressed.

When the alkali-developable resin is a carboxyl group-containing resin, it can be developed as a weakly alkaline aqueous solution compared to the case of a phenolic resin. As a weakly alkaline aqueous solution, what melt | dissolved sodium carbonate etc. is mentioned. By developing with a weakly alkaline aqueous solution, it is possible to suppress that the light irradiation portion is developed. Moreover, the light irradiation time in process (B) and the heating time in process (B1) can be shortened.

[Thermoreactive compound]

The heat-reactive compound is a resin having a functional group capable of curing reaction by heat. And epoxy resins and polyfunctional oxetane compounds.

The said epoxy resin is a resin which has an epoxy group, and any well-known thing can be used. And bifunctional epoxy resins having two epoxy groups in the molecule, polyfunctional epoxy resins having a large number of epoxy groups in the molecule, and the like. Further, a hydrogenated bifunctional epoxy compound may be used.

As a polyfunctional epoxy compound, bisphenol A type epoxy resin, brominated epoxy resin, novolak type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, glycidylamine type epoxy resin, hydantoin type epoxy resin, Alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bixylenol type or biphenol type epoxy resin or mixtures thereof, bisphenol S type epoxy resin, bisphenol A novolac type epoxy resin, tetraphenylolethane type epoxy resin, complex Cyclic epoxy resin, diglycidyl phthalate resin, tetraglycidyl xylenoethane resin, naphthalene group-containing epoxy resin, epoxy resin having a dicyclopentadiene skeleton, glycidyl methacrylate copolymer epoxy resin, cyclohexyl maleay And copolymerized epoxy resins of mid and glycidyl methacrylate, and CTBN-modified epoxy resins.

As other liquid bifunctional epoxy resins, vinylcyclohexenediepoxide, (3 ', 4'-epoxycyclohexylmethyl) -3,4-epoxycyclohexanecarboxylate, (3', 4'-epoxy- And alicyclic epoxy resins such as 6'-methylcyclohexylmethyl) -3,4-epoxy-6-methylcyclohexanecarboxylate. The naphthalene group-containing epoxy resin is preferable because it can suppress thermal expansion of the cured product.

As for the said epoxy resin, 1 type may be used individually and 2 or more types may be used together.

Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [ (3-methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl Acrylate, (3-ethyl-3-oxetanyl) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate In addition to polyfunctional oxetane such as oligomers or copolymers thereof, oxetane alcohol and novolac resin, poly (p-hydroxystyrene), cardo-type bisphenols, calix arenes, calix resorcincin arenes, or And etherified products with resins having hydroxyl groups such as silsesquioxane. In addition, copolymers of unsaturated monomers having an oxetane ring and alkyl (meth) acrylates are also exemplified.

Here, when the heat-reactive compound has a benzene skeleton, it is preferable because the heat resistance is improved. Moreover, when a thermosetting resin composition contains a white pigment, it is preferable that a thermoreactive compound is an alicyclic skeleton. Thereby, photoreactivity can be improved.

As a compounding quantity of the said heat-reactive compound, it is preferable that the equivalent ratio (heat-reactive group: alkali-developable group) with alkali-developable resin is 1: 0.1-1: 10, and it is more preferable that it is 1: 0.2-1: 5. When it is within the range of such a compounding ratio, the development becomes good.

[Photobase generator]

The photobase generator is a compound that generates one or more basic substances capable of functioning as a catalyst for the addition reaction of the above-mentioned heat-reactive compound by changing the molecular structure by irradiation of light such as ultraviolet rays or visible light, or by cleaving the molecule. to be. As a basic substance, secondary amine and tertiary amine are mentioned, for example.

As a photobase generator, for example, α-aminoacetophenone compound, oxime ester compound, acyloxyimino group, N-formylated aromatic amino group, N-acylated aromatic amino group, nitrobenzyl carbamate group, alkoxybenzylcar And compounds having a substituent such as a barmate group.

The α-aminoacetophenone compound has a benzoin ether bond in the molecule, and upon irradiation with light, cleavage occurs in the molecule, thereby generating a basic substance (amine) that exerts a curing catalytic action. Specific examples of the α-aminoacetophenone compound include (4-morpholinobenzoyl) -1-benzyl-1-dimethylaminopropane (Irgacure 369, trade name, manufactured by BASF Japan) or 4- (methylthiobenzoyl)- 1-methyl-1-morpholinoethane (Irgacure 907, trade name, manufactured by BASF Japan), 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4- Commercially available compounds such as morpholinyl) phenyl] -1-butanone (Irgacure 379, trade name, manufactured by BASF Japan) or a solution thereof.

As the oxime ester compound, any compound that generates a basic substance by light irradiation can be used. As a commercial item, CGI-325 by a BASF Japan company, Irgacure-OXE01, Irgacure-OXE02, N-1919 by Adeka Corporation, NCI-831 etc. are mentioned as a commercial item. Further, a compound having two oxime ester groups in the molecule can also be suitably used, and specifically, an oxime ester compound having a carbazole structure represented by the following formula is mentioned.

(Wherein X is a hydrogen atom, an alkyl group having 1 to 17 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a phenyl group, a phenyl group (an alkyl group having 1 to 17 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an amino group, an alkyl group having 1 to 8 carbon atoms) Substituted by an alkylamino group or a dialkylamino group having a), a naphthyl group (an alkyl group having 1 to 17 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an amino group, an alkylamino group having an alkyl group having 1 to 8 carbon atoms, or a dialkylamino group) Y, Z are each a hydrogen atom, an alkyl group having 1 to 17 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogen group, a phenyl group, or a phenyl group (an alkyl group having 1 to 17 carbon atoms, 1 to 8 carbon atoms). Alkoxy group, amino group, alkylamino group having an alkyl group having 1 to 8 carbon atoms or substituted by dialkylamino group), naphthyl group (alkyl group having 1 to 17 carbon atoms, alkoxy group having 1 to 8 carbon atoms, amino group, 1 to 8 carbon atoms Substituted with an alkylamino group or a dialkylamino group having an alkyl group of), anthryl group, pyridyl group, benzofuryl group, benzothienyl group, Ar is a bond, or alkylene having 1 to 10 carbon atoms, vinylene, Phenylene, biphenylene, pyridylene, naphthylene, thiophene, anthylene, thienylene, furylene, 2,5-pyrrole-diyl, 4,4'-stilbene-diyl, 4,2'-styrene -Diyl, n is an integer of 0 or 1)

In particular, in the above formula, X and Y are each a methyl group or an ethyl group, Z is methyl or phenyl, n is 0, and Ar is a bond, preferably phenylene, naphthylene, thiophene or thienylene.

Moreover, as a preferable carbazole oxime ester compound, the compound which can be represented by the following formula is also mentioned.

(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, and R ² is 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 an alkoxy group having 1 to 4 carbon atoms, and R ³ may be connected with an oxygen atom or a sulfur atom, or substituted with a phenyl group An alkyl group having 1 to 20 carbon atoms which may be substituted, a benzyl group which may be substituted with an alkoxy group having 1 to 4 carbon atoms, R ⁴ represents a nitro group, or an acyl group represented by XC (= O)- , X represents an aryl group, a thienyl group, a morpholino group, a thiophenyl group, or a structure represented by the following formula, which may be substituted with an alkyl group having 1 to 4 carbon atoms)

Others: Japanese Patent Publication No. 2004-359639, Japanese Patent Publication No. 2005-097141, Japanese Patent Publication No. 2005-220097, Japanese Patent Publication No. 2006-160634, Japanese Patent Publication No. 2008-094770 And carbazole oxime ester compounds described in Japanese Patent Publication No. 2008-509967, Japanese Patent Publication No. 2009-040762, and Japanese Patent Publication No. 2011-80036.

Specific examples of the compound having an acyloxyimino group include O, O'-succinate diacetophenone oxime, O, O'-succinate dinaphthophenone oxime, benzophenone oxime acrylate copolymer, and the like.

Specific examples of the compound having an N-formylated aromatic amino group or an N-acylated aromatic amino group include, for example, di-N- (p-formylamino) diphenylmethane, di-N (p-acetylamino) diphenylmellan , Di-N- (p-benzoamide) diphenylmethane, 4-formylaminotoluene, 4-acetylaminotoluylene, 2,4-diformylaminotoluylene, 1-formylaminonaphthalene, 1- Acetylaminonaphthalene, 1,5-diformylaminonaphthalene, 1-formylaminoanthracene, 1,4-diformylaminoanthracene, 1-acetylaminoanthracene, 1,4-diformylaminoanthraquinone, 1, 5-diformylamino anthrakinone, 3,3'-dimethyl-4,4'-diformylaminobiphenyl, 4,4'-diformylaminobenzophenone, etc. are mentioned.

As a specific example of the compound which has a nitrobenzyl carbamate group and an alkoxybenzyl carbamate group, bis {{(2-nitrobenzyl) oxy} carbonyl} diaminodiphenylmethane, 2,4-di {{( 2-nitrobenzyl) oxy} toluylene, bis {{(2-nitrobenzyloxy) carbonyl} hexane-1,6-diamine, m-xylidine {{(2-nitro-4-chlorobenzyl) oxy} Amide} and the like.

As the photobase generator, oxime ester compounds and α-aminoacetophenone compounds are preferable. As the α-aminoacetophenone compound, it is particularly preferable to have two or more nitrogen atoms.

As other photobase generators,

WPBG-018 (trade name: 9-anthrylmethyl N, N'-diethylcarbamate), WPBG-027 (trade name: (E) -1- [3- (2-hydroxyphenyl) -2-prope Noil] piperidine), WPBG-082 (brand name: guanidinium 2- (3-benzoylphenyl) propionate), WPBG-140 (brand name: 1- (anthraquinone-2-yl) ethyl imidazole carboxyl Rate) and the like.

In addition, Japanese Patent Publication No. Hei 11-71450, International Publication 2002/051905, International Publication 2008/072651, Japanese Patent Publication No. 2003-20339, Japanese Patent Publication No. 2003-212856, Japanese Patent Publication No. 2003-344992, Japanese Patent Publication No. 2007-86763, Japanese Patent Publication No. 2007-231235, Japanese Patent Publication No. 2008-3581, Japanese Patent Publication No. 2008-3582, Japanese Patent Publication No. 2009-280785, Japanese Patent Publication No. 2009-080452, Japanese Patent Publication No. 2010-95686, Japanese Patent Publication No. 2010-126662, Japanese Patent Publication No. 2010-185010, Japanese Patent Publication No. 2010-185036 Publication, Japanese Patent Publication No. 2010-186054, Japanese Patent Publication No. 2010-186056, Japanese Patent Publication No. 2010-275388, Japanese Patent Publication No. 2010-222586, Japanese Patent Publication No. 2010-084144, Japanese Patent Publication It is also possible to use a photobase generator described in documents such as Japanese Unexamined Patent Publication No. 2011-107199, Japanese Patent Publication No. 2011-236416, Japanese Patent Publication No. 2011-080032.

The photobase generator 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 parts by mass, more preferably 1 to 40 parts by mass with respect to 100 parts by mass of the thermally reactive compound. When it is less than 1 part by mass, development may be difficult, which is not preferable.

[Maleimide compound]

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

Examples of the maleimide compound include polyfunctional aliphatic / alicyclic maleimide and polyfunctional aromatic maleimide. A bifunctional or higher maleimide compound (polyfunctional maleimide compound) is preferred. Examples of the polyfunctional aliphatic / alicyclic maleimide include N, N'-methylenebismaleimide, N, N'-ethylenebismaleimide, tris (hydroxyethyl) isocyanurate and aliphatic / alicyclic maleimide. A maleimide ester compound having an isocyanurate skeleton obtained by dehydrating and esterifying a carboxylic acid; Isocyanurate skeleton polymaleimides such as maleimide urethane compounds of isocyanurate skeleton obtained by urethanizing tris (carbamatehexyl) isocyanurate and aliphatic / alicyclic maleimide alcohols; Dehydration esterification of isophorone bis urethane bis (N-ethyl maleimide), triethylene glycol bis (maleimide ethyl carbonate), aliphatic / alicyclic maleimide carboxylic acid and various aliphatic / alicyclic polyols, or aliphatic / alicyclic Aliphatic / alicyclic polymaleimide ester compounds obtained by transesterifying a group maleimide carboxylic acid ester with various aliphatic / alicyclic polyols; Aliphatic / alicyclic polymaleimide ester compounds obtained by ether ring-opening reaction of aliphatic / alicyclic maleimide carboxylic acid with various aliphatic / alicyclic polyepoxides; And aliphatic / alicyclic polymaleimide urethane compounds obtained by urethanizing an aliphatic / alicyclic maleimide alcohol with various aliphatic / alicyclic polyisocyanates.

Examples of the polyfunctional aromatic maleimide include aromatic polymaleimide ester compounds obtained by dehydrating esterification of maleimide carboxylic acid and various aromatic polyols or transesterification reaction of maleimide carboxylic acid ester and various aromatic polyols; Aromatic polymaleimide ester compounds obtained by ether ring-opening reaction of maleimide carboxylic acid and various aromatic polyepoxides; And aromatic polyfunctional maleimides such as aromatic polymaleimide urethane compounds obtained by urethanizing a maleimide alcohol with various aromatic polyisocyanates.

Specific examples of the polyfunctional aromatic maleimide include, for example, N, N '-(4,4'-diphenylmethane) bismaleimide, N, N'-2,4-tolylenebismaleimide, N, N' -2,6-tolylenebismaleimide, 1-methyl-2,4-bismaleimidebenzene, N, N'-m-phenylenebismaleimide, N, N'-p-phenylenebismaleimide, N, N'-m-toluylene bismaleimide, N, N'-4,4'-biphenylenebismaleimide, N, N'-4,4 '-[3,3'-dimethyl-biphenyl Len] bismaleimide, N, N'-4,4 '-[3,3'-dimethyldiphenylmethane] bismaleimide, N, N'-4,4'-[3,3'-diethyldi Phenylmethane] bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4'-diphenylpropanebismaleimide, N, N'-4,4 ' -Diphenyl ether bismaleimide, N, N'-3,3'-diphenylsulfone bismaleimide, N, N'-4,4'-diphenylsulfone bismaleimide, 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-malelay) Midphenoxy) -5-t-butylphenyl] -2-methylpropane, 4,4'-cyclohexylidene-bis [1- (4-maleimidephenoxy) -2- (1,1-dimethylethyl ) Benzene], 4,4'-methylene-bis [1- (4-maleimidephenoxy) -2,6-bis (1,1-dimethylethyl) benzene], 4,4'-methylene-bis [1 -(4-maleimidephenoxy) -2,6-di-s-butylbenzene], 4,4'-cyclohexylidene-bis [1- (4-maleimidephenoxy) -2-cyclohexylbenzene , 4,4'-methylenebis [1- (maleimidephenoxy) -2-nonylbenzene], 4,4 '-(1-methylethylidene) -bis [1- (maleimidephenoxy) -2 , 6-bis (1,1-dimethylethyl) benzene], 4,4 '-(2-ethylhexylidene) -bis [1- (maleimidephenoxy) -benzene], 4,4'-(1 -Methylheptylidene) -bis [1- (maleimidephenoxy) -benzene], 4,4'-cyclohexylidene-bis [1- (maleimidephenoxy) -3-methylbenzene], 2, 2-bis (4- (4-maleimide phenoxy) phen Neal] hexafluoropropane, 2,2-bis [3-methyl-4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3-methyl-4- (4-maleimidephenoxy) ) Phenyl] hexafluoropropane, 2,2-bis [3,5-dimethyl-4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3,5-dimethyl-4- (4 -Maleimidephenoxy) phenyl] hexafluoropropane, 2,2-bis [3-ethyl-4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3-ethyl-4- ( 4-maleimidephenoxy) phenyl] hexafluoropropane, bis [3-methyl- (4-maleimidephenoxy) phenyl] methane, bis [3,5-dimethyl- (4-maleimidephenoxy) phenyl] Methane, bis [3-ethyl- (4-maleimidephenoxy) phenyl] methane, 3,8-bis [4- (4-maleimidephenoxy) phenyl] -tricyclo [5.2.1.02,6] decane, 4,8-bis [4- (4-maleimidephenoxy) phenyl] -tricyclo [5.2.1.02,6] decane, 3,9-bis [4- (4-maleimidephenoxy) phenyl] -tri Cyclo [5.2.1.02,6] decane, 4,9-bis [4- (4-maleimidephenoxy) phenyl] -tricyclo [5.2.1.02,6] decane, 1,8-bis [4- (4 -Maleimidephenoxy) phenyl] mentan, 1,8-bis [3-methyl-4- (4-maleimidephenoxy) phenyl] mentan, 1,8-bis [3,5-dimethyl-4- (4 -Maleimide phenoxy) phenyl] mentane and the like.

As a compounding quantity of a maleimide compound, it is preferable that the equivalent ratio (maleimide group: alkali developable group) with alkali developable resin is 1: 0.1-1: 10, and it is more preferable that it is 1: 0.2-1: 5. The development becomes easy by setting it as such a compounding ratio.

[Polymer resin]

In the thermosetting resin composition of the present invention, conventionally known polymer resins can be blended for the purpose of improving flexibility and dryness of touch of the resulting cured product.

Examples of the polymer resin include cellulose, polyester, phenoxy resin, polyvinyl acetal, polyvinyl butyral, polyamide, and polyamideimide binder polymers, block copolymers, elastomers, and rubber particles. One type of polymer resin may be used alone, or two or more types may be used in combination.

By blending the polymer resin, the melt viscosity of the thermosetting resin composition increases, and the resin fluidity of the through-hole portion can be suppressed during heating after exposure. As a result, a flat substrate with no concave portion visible on the through hole can be produced.

The addition amount of the polymer resin is preferably 50 parts by mass or less, more preferably 1 to 30 parts by mass, particularly preferably 5 to 30 parts by mass, relative to 100 parts by mass of the heat-reactive compound. When the blending amount of the polymer resin exceeds 50 parts by mass, it is not preferable because the deterioration of the desmear resistance of the thermosetting resin composition is concerned.

(Block copolymer)

The block copolymer is a copolymer having a molecular structure in which two or more kinds of polymers having different properties are connected by covalent bonds to form a long chain.

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, the central B is a soft block, the glass transition point Tg is low, preferably less than 0 ° C, and both outer A or A' are hard blocks and the Tg is high, preferably It is preferable that it is comprised by polymer units of 0 degreeC or more. The glass transition point Tg is measured by differential scanning calorimetry (DSC).

Further, among the ABA or AB-A 'type block copolymers, A or A' is more preferably a block copolymer comprising a polymer unit having a Tg of 50 ° C or higher, and B containing a polymer unit having a Tg of -20 ° C or lower. .

Further, among the A-B-A or A-B-A 'type block copolymers, it is preferable that A or A' has high compatibility with the heat-reactive compound, and it is preferred that B has low compatibility with the heat-reactive compound. In this way, it is considered that the blocks at both ends are compatible with the matrix and the central block is used as a block copolymer incompatible with the matrix, so that it is easy to exhibit a specific structure in the matrix.

As A or A ', it is preferable to include polymethyl (meth) acrylate (PMMA), polystyrene (PS), and the like, and as B, polyn-butyl acrylate (PBA), polybutadiene (PB), and the like are included. It is preferred. In addition, by introducing a hydrophilic unit excellent in compatibility with the matrix described above represented by a styrene unit, a hydroxyl group-containing unit, a carboxyl group-containing unit, an epoxy-containing unit, an N-substituted acrylamide unit, etc., in a part of the A or A 'component, It becomes possible to further improve the compatibility.

In addition, as the block copolymer used in the present invention, a block copolymer of three or more members is preferable, and a block copolymer whose molecular structure synthesized by living polymerization method is precisely controlled is more preferable in obtaining the effect of the present invention. 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 each unit have been clarified. The molecular weight distribution (Mw / Mn) of the block copolymer to be used is preferably 3 or less, more preferably 2.5 or less, and even more preferably 2.0 or less.

Block copolymers comprising such (meth) acrylate polymer blocks include, for example, the methods described in Japanese Patent Publication No. 2007-516326, Japanese Patent Publication No. 2005-515281, in particular the following formulas (1) to ( After polymerizing the Y unit with the alkoxy amine compound represented by any of 4) as an initiator, it can be suitably obtained by polymerizing the X unit.

(Wherein, n represents 2, Z represents a divalent organic group, preferably 1,2-ethanedioxy, 1,3-propanedioxy, 1,4-butanedioxy, 1,6-hexane Dioxy, 1,3,5-tris (2-ethoxy) cyanuric acid, polyaminoamine, for example polyethyleneamine, 1,3,5-tris (2-ethylamino) cyanuric acid, polythioxy , Phosphonate or polyphosphonate, Ar represents a divalent aryl group)

The weight average molecular weight of the block copolymer is preferably in the range of 20,000 to 400,000, more preferably 50,000 to 300,000. If the weight average molecular weight is less than 20,000, the desired toughness and flexibility effects are not obtained, and the adhesiveness when the thermosetting resin composition is dry-filmed or applied to a substrate and pre-dried is also poor. On the other hand, when the weight average molecular weight exceeds 400,000, the viscosity of the thermosetting resin composition becomes high, and printability and workability may be remarkably deteriorated. When the weight average molecular weight is 50,000 or more, an excellent effect is obtained in mitigation against impact from the outside.

As a polymer resin, a block copolymer is preferable because it has excellent crack resistance during cold / heat cycle and can suppress warpage after curing. The block copolymer is particularly preferable because it can suppress a concave portion on the through-hole and can produce a substrate having a flat surface. In addition, by combining the inorganic filler, it is also excellent in crack resistance during cold / heat cycle.

(Elastomer)

An elastomer having a functional group can be added to the thermosetting resin composition of the present invention. By adding an elastomer having a functional group, it can be expected that the coating properties are improved and the strength of the coating film is also improved. In addition, polyester-based elastomers, polyurethane-based elastomers, polyester-based elastomers, polyamide-based elastomers, polyesteramide-based elastomers, acrylic-based elastomers, olefin-based elastomers, and the like can be used. Further, resins in which some or all of the epoxy groups having various skeletons are modified with both terminal carboxylic acid-modified butadiene-acrylonitrile rubbers can be used. Furthermore, epoxy-containing polybutadiene-based elastomers, acrylic-containing polybutadiene-based elastomers, hydroxyl-containing polybutadiene-based elastomers, and hydroxyl-containing isoprene-based elastomers can also be used. Moreover, this elastomer can be used individually by 1 type, and 2 or more types can also be used together.

(Rubber particles)

The rubber particles may be any particles as long as they are in the form of particles formed from organic substances such as polymers having a cross-linked structure. For example, as a copolymer of acrylonitrile butadiene, cross-linked NBR particles obtained by copolymerizing acrylonitrile and butadiene; Copolymerization of acrylonitrile and carboxylic acid such as butadiene and acrylic acid; And so-called cross-linked rubber particles (also referred to as "core-shell rubber particles") having a core-shell structure in which a cross-linked polybutadiene, cross-linked silicone rubber, or NBR is used as a core layer and a cross-linked acrylic resin is used as a shell layer.

Among them, from the viewpoint of control of dispersibility and stability of particle size, cross-linked rubber particles having a core shell structure are preferred, and a core shell structure comprising a cross-linked acrylic resin as a shell layer and a cross-linked polybutadiene or cross-linked silicone rubber as a core layer. Crosslinked rubber particles are more preferred.

The crosslinked NBR particles are those obtained by copolymerizing acrylonitrile and butadiene, and partially crosslinking in the step of copolymerizing to form a particle. Moreover, it is also possible to obtain carboxylic acid-modified crosslinked NBR particles by copolymerizing carboxylic acids such as acrylic acid and methacrylic acid together.

The core-shell rubber particles of the crosslinked butadiene rubber-crosslinked acrylic resin can be obtained by a two-step polymerization method in which polymerization of butadiene particles is performed by emulsion polymerization and polymerization is continued by adding monomers such as acrylic acid esters and acrylic acid.

The core-shell rubber particles of the crosslinked silicone rubber-crosslinked acrylic resin can be obtained by a two-step polymerization method in which silicone particles are polymerized by emulsion polymerization, and then polymerization is continued by adding monomers such as acrylic acid ester and acrylic acid.

The size of the rubber particles is 1 µm or less as the primary average particle diameter, and is preferably 50 nm to 1 µm. When the primary average particle diameter exceeds 1 µm, the adhesive strength is lowered and the insulation reliability in fine wiring is impaired. The term "primary average particle diameter" as used herein refers to aggregated particle diameter, that is, not a secondary particle diameter, but a particle diameter in a group that is not aggregated.

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

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 less in the resin composition, and more preferably 1 to 30% by mass.

For example, commercially available products of carboxylic acid-modified acrylonitrile-butadiene rubber particles include Nippon Kosei Rubber Co., Ltd. XER-91. Examples of the core shell particles of the butadiene rubber-acrylic resin include Paraloid EXL2655 manufactured by Rohm and Haas Co., Ltd. and AC-3832 manufactured by Kantsu Kasei High School Co., Ltd. As a core-shell rubber particle of a crosslinked silicone rubber-acrylic resin, Asahi Kasei Barker Silicone Co., Ltd. product is GENIOPERLP52.

By using the rubber particles, it is possible to improve crack resistance during a cold / heat cycle.

[Inorganic filler]

The thermosetting resin composition contains an inorganic filler. The inorganic filler is used to suppress the curing shrinkage of the cured product of the thermosetting resin composition, and to improve properties such as adhesion and hardness. As the inorganic filler, for example, barium sulfate, amorphous silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, aluminum nitride, boron nitride, Neuburg Silica Earth, etc. Can be heard.

The average particle diameter (D50) of the inorganic filler is preferably 1 μm or less, more preferably 0.7 μm or less, and even more preferably 0.5 μm. When the average particle diameter exceeds 1 μm, it is not preferable because the pattern layer may become cloudy. The lower limit of the average particle diameter (D50) of the inorganic filler is not particularly limited, but is, for example, 0.01 µm or more. Here, the average particle diameter (D50) means the average primary particle diameter.

The average particle diameter (D50) can be measured by laser diffraction / scattering. When the average particle diameter is in the above range, the refractive index becomes closer to the resin component, the transmittance is improved, and the generation efficiency of the base from the photobase generator by light irradiation increases.

It is preferable that the refractive index difference between the inorganic filler and the alkali developable resin is 0.3 or less. By setting the refractive index difference to 0.3 or less, scattering of light is suppressed, and good core hardening properties can be obtained. Here, the refractive index of the inorganic filler is preferably 1.4 or more and 1.8 or less. In addition, the refractive index of an inorganic filler can be measured according to JIS K 7105.

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

In a composition in which curing proceeds by radical reaction, the resolution decreases when the content of the inorganic filler increases, but in the present invention, because the curing reaction is caused by the generated base, good resolution is maintained even when the content of the inorganic filler increases. Can be.

Further, the specific gravity of the inorganic filler is preferably 3 or less, more preferably 2.8 or less, and even more preferably 2.5 or less. When the specific gravity of the inorganic filler is 3 or less, thermal expansion can be suppressed. Examples of the inorganic filler of 3 or less include silica and aluminum hydroxide, and silica is particularly preferred.

Examples of the shape of the inorganic filler include an irregular shape, a needle shape, a disk shape, scaly pieces, a spherical shape, and a hollow shape. Here, since a composition can be blended at a high ratio, a spherical shape is preferable. Further, in order to improve the moisture resistance, the inorganic filler is more preferably treated with a surface treatment agent such as a silane coupling agent.

Moreover, by containing an inorganic filler, crack resistance at the time of a cold-heat cycle can be improved. By containing a large amount of the inorganic filler, warpage after curing can also be suppressed.

In this invention, it is preferable that the thermal expansion coefficient (CTE) of hardened | cured material is 40 ppm or less, More preferably, it is 30 ppm or less, More preferably, it is 20 ppm or less.

[Organic solvent]

In the thermosetting resin composition of the present invention, an organic solvent can be used for the production of a resin composition or for adjusting the viscosity for applying to a substrate or a carrier film.

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

[Photopolymerizable monomer]

The thermosetting resin composition of this invention may contain the photopolymerizable monomer in the range which does not inhibit the effect of this invention.

Examples of the photopolymerizable monomer include alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; Mono or di (meth) acrylates of alkylene oxide derivatives such as ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol; Polyhydric alcohols such as hexanediol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, and trishydroxyethyl isocyanurate, or polyvalent (meth) acrylates of ethylene oxide or propylene oxide adducts Ryu; (Meth) acrylates of ethylene oxide or propylene oxide adducts of phenols such as phenoxyethyl (meth) acrylate and polyethoxydi (meth) acrylate of bisphenol A; (Meth) acrylates of glycidyl ethers such as glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, and triglycidyl isocyanurate; And melamine (meth) acrylate.

The blending amount of the photopolymerizable monomer is preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 15% by mass or less, based on the solid content excluding the solvent of the thermosetting resin composition. When the blending amount of the photopolymerizable monomer exceeds 50% by mass, since the curing shrinkage increases, the warpage may increase. Moreover, when a photopolymerizable monomer is derived from (meth) acrylate, it contains an ester bond. In this case, since the hydrolysis of the ester bond occurs by the desmear treatment, there is a possibility that the electrical properties are lowered.

(Other optional ingredients)

In the thermosetting resin composition of the present invention, if necessary, components such as a mercapto compound, an adhesion promoter, a colorant, an antioxidant, and an ultraviolet absorber can be further blended.

In particular, in the present invention, even when the content of the colorant is increased, undercut can be suppressed to form good via holes and lines.

These can use well-known things in the field of electronic materials. In addition, the above thermosetting resin compositions include known conventional thickeners such as finely divided silica, hydrotalcite, organic bentonite, montmorillonite, antifoaming agents such as silicone-based, fluorine-based, polymer-based and / or leveling agents, silane coupling agents, rust inhibitors, etc. Conventional additives can be blended.

Moreover, you may mix | blend well-known conventional thermosetting resins, such as a block isocyanate compound, an amino resin, a benzoxazine resin, a carbodiimide resin, a cyclocarbonate compound, an episulfide resin, as a thermosetting component.

In addition, by containing a phenol resin as an alkali developable resin and an epoxy resin as a heat-reactive compound, the Tg can be made high, and a resin composition that can obtain a cured product excellent in HAST resistance without depending on the softening point of the raw material can be obtained. have. In addition, when the composition is a composition that does not mix the photopolymerizable monomer (in the photocurable resin composition containing an ethylenically unsaturated group in the molecule, and containing a carboxyl group-containing resin as a main component, to promote photocuring), the tag is used. It can be set as a resin composition having excellent properties.

In the conventional photocurable resin composition, since the photocuring reaction occurs at room temperature, as a result of the Tg of the resin composition rising during curing, the curing reaction may be stopped, and it is necessary to design the Tg of the resin composition low. . On the other hand, the alkali-developable thermosetting resin composition of the present invention is not limited to Tg before the curing reaction, and can be expected to be a high Tg. Moreover, the alkali developing type thermosetting resin composition of this invention can be expected to harden, without being inhibited 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 a solder resist or an interlayer insulating layer.

[Pattern formation method]

The pattern forming method that can suitably use the thermosetting resin composition of the present invention includes the step (A) of forming a resin layer containing a thermosetting resin composition on a substrate, and irradiating light in a negative pattern shape to be included in the thermosetting resin composition It includes the process (B) of activating a photobase generator and hardening the light irradiation part, and the process (C) of forming a negative pattern layer by removing an unradiated part by alkali development.

The light irradiation portion can be cured by generating a base in the light irradiation portion of the thermosetting resin composition by pattern-shaped light irradiation. Thereafter, by developing with an aqueous alkali solution, the unirradiated portion can be removed to form a negative pattern layer.

Here, in this invention, it is preferable to have the process (B1) which heats a resin layer after a process (B). Thereby, the resin layer is sufficiently hardened, and a pattern layer excellent in hardening properties can be obtained.

[Process (A)]

A pattern forming method will be described with reference to FIG. 1. Step (A) is a step of forming a resin layer containing a thermosetting resin composition on a substrate. The method of forming the resin layer may be a method of applying and drying a liquid thermosetting resin composition on a substrate, or a method of laminating a thermosetting resin composition as a dry film on a substrate.

As a method of applying the thermosetting resin composition to the substrate, a known method such as a blade coater, a lip coater, a comma coater, or a film coater can be suitably employed. In addition, the drying method uses a hot air circulation type drying furnace, an IR furnace, a hot plate, a convection oven, or the like equipped with a heat source of a heating method using steam, a method of countercurrently contacting hot air in a dryer, and a support from a nozzle Well-known methods, such as a method of spraying, can be applied.

As the base material, in addition to the pre-circuited printed wiring base material or flexible printed wiring base material, paper-phenolic resin, paper-epoxy resin, glass cloth-epoxy resin, glass-polyimide, glass cloth / nonwoven fabric-epoxy resin, glass cloth / paper- Copper grade laminates of all grades (such as FR-4), polyimide films, PET films, glass substrates, ceramic substrates, wafers using composites such as epoxy resins, synthetic fiber-epoxy resins, fluorine resins, polyethylenes, PPOs, and cyanate esters Substrates and the like can be used.

[Process (B)]

Step (B) is a step of curing a light irradiation portion by activating a photobase generator contained in the thermosetting resin composition by irradiating light in a negative pattern shape. In the step (B), it is thought that the photobase generator destabilizes with the base generated in the light irradiation section, and further generates base. By chemically propagating the base in this way, it is possible to sufficiently cure even the deep portion of the light irradiation portion.

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

As the active energy ray, it is preferable to use laser light or scattered light having a maximum wavelength in the range of 350 to 410 nm. By setting the maximum wavelength in this range, it is possible to efficiently improve the thermal reactivity of the thermosetting resin composition. If a laser light in this range is used, either a gas laser or a solid laser may be used. In addition, the irradiation amount differs depending on the film thickness and the like, and can generally be within the range of 100 to 1500 mJ / cm 2, preferably 300 to 1500 mJ / cm 2.

As the direct drawing device, for example, Nippon Orbotech Co., Ltd. or Pantax Co., Ltd. can be used, and any device may be used as long as it is a device that emits laser light having a maximum wavelength of 350 to 410 nm.

[Process (B1)]

Step (B1) hardens the light irradiation portion by heating. Step (B1) can be cured to the core by the base generated in step (B).

It is preferable that the heating temperature is a temperature at which the light irradiating portion of the thermosetting resin composition is thermosetting, but the non-irradiating portion is not thermosetting.

For example, step (B1) is preferably lower than the exothermic onset temperature or exothermic peak temperature of the unirradiated thermosetting resin composition, and preferably heated at a temperature higher than the exothermic onset temperature or exothermic peak temperature of the light-irradiated thermosetting resin composition. By heating in this way, only the light irradiation portion can be selectively cured.

Here, heating temperature is 80-140 degreeC, for example. 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 portion can be selectively cured. The heating time is, for example, 10 to 100 minutes. The heating method is the same as the above drying method.

In addition, in the non-irradiated portion, since no base is generated from the photobase generator, thermal curing is suppressed.

[Process (C)]

Step (C) is a step of forming a negative pattern layer by removing the unirradiated portion by development. As a developing method, it can be based on well-known methods, such as a dipping method, a shower method, a spray method, and a brush method. Further, as the developer, amines such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, and ethanolamine, alkali aqueous solutions such as aqueous tetramethylammonium hydroxide (TMAH), or mixtures thereof can be used. .

[Process (D)]

It is preferable that the said pattern formation method further contains an ultraviolet irradiation process (D) after process (C). By further irradiating ultraviolet rays after the step (C), it is possible to activate the photobase generator remaining without activation during light irradiation. 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). A suitable irradiation amount (irradiation amount) is 150 to 2000 mJ / cm 2.

[Process (E)]

It is preferable that the said pattern formation method further contains a thermosetting (post-curing) process (E) after a process (C).

When both process (D) and process (E) are performed after process (C), it is preferable to perform process (E) after process (D).

In the step (E), the pattern layer is sufficiently heat-cured with the base generated from the photobase generator by the step (B) or the steps (B) and (D). At the time of the step (E), since the unirradiated portion has already been removed, the step (E) can be performed at a temperature equal to or higher than the temperature at which the uncured thermosetting resin composition starts to cure. Thereby, the pattern layer can be sufficiently heat-cured. The heating temperature is, for example, 160 ° C or higher.

[Process (F)]

The pattern forming method may further include a laser processing step (F). A fine opening can be formed by laser processing. As the laser, a known laser such as a YAG laser, a CO ₂ laser, or an excimer laser can be used.

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

[Process (G)]

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

The process (G) includes a smear swelling process for swelling the smear so that it can be easily removed, a removal process for removing the smear, and a neutralization process for neutralizing sludge generated from the desmear liquid used in the removal process.

The swelling process is performed by using an alkali chemical solution such as sodium hydroxide, which facilitates the removal of smear by the desmear chemical solution.

In the removal step, smear is removed using an acidic chemical solution containing an oxidizing agent such as dichromic acid or permanganic acid.

In the neutralization process, an alkali chemical such as sodium hydroxide is used to reduce and remove the oxidizing agent used in the removal process.

Example

Hereinafter, the present invention will be described in more detail with reference to 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 developing type thermosetting resin composition>

According to the formulations shown in Tables 1 to 3, the materials described in Examples / Comparative Examples were respectively formulated, pre-mixed with a stirrer, and kneaded with three roll mills to prepare a thermosetting resin composition. The values in the table are parts by mass unless otherwise specified.

<Production of dry film>

As a carrier film, a thermosetting resin composition was applied on a PET film having a thickness of 38 μm using an applicator, and then dried at 90 ° C./30 minutes to produce a dry film. After drying the thickness of the thermosetting resin composition, the coating amount was adjusted to be about 20 μm. Then, the obtained dry film was slit-processed to a predetermined size.

<Laminate>

A double-sided printed wiring substrate having a circuit having a copper thickness of 15 µm was prepared, and pre-treated using CZ-8100 from Mack, and dry film on the printed wiring board using vacuum laminator MVLP-500 from Macy. Was laminated. Lamination conditions were performed at a temperature of 80 ° C and a pressure of 5 kg / cm 2/60 seconds.

<Evaluation of B stage state (handling at the time of formation to a base material)>

With respect to Examples 1 to 19, evaluation of the B-stage state (semi-cured state) of the dry film was performed. Slit processing was performed at a predetermined size of the dry film on which the obtained thermosetting resin composition was formed, and the state of the dry film was confirmed by the following method.

(Assessment Methods)

(Circle): After slit processing, cracking of the resin layer and powder fall of the resin were not observed.

(Triangle | delta): After slit processing, the crack of a resin layer and the powder fall of resin were confirmed.

<Evaluation of the recess on the through hole>

As shown in Fig. 3, a double-sided printed wiring substrate having a diameter of 300 µm and a pitch of 1 mm in which copper plating through-holes are formed at intervals of 1 mm is prepared, and pretreatment is performed using CZ-8100 manufactured by Mack. Did. Thereafter, a dry film having a thickness of 50 µm, which was produced by the method described in the production section of the dry film, was laminated on both sides of the printed wiring substrate having a through hole formed thereon using a vacuum laminator MVLP-500 manufactured by Meiki Corporation. Did. Lamination conditions were performed at a temperature of 80 ° C and a pressure of 5 kg / cm 2/60 seconds. Subsequently, the base material provided with the thermosetting resin layer was irradiated with light by solid surface exposure on both front and back sides with ORMW HMW680GW (metal halide lamp, scattered light). About the light irradiation amount, the exothermic peak temperature by DSC was set as described in Tables 1-3. Subsequently, the substrate was vertically hung for 60 to 80 minutes under the temperature conditions shown in Tables 1 to 3, and heat treatment was performed. Moreover, ultraviolet irradiation was performed with ORC's ultraviolet irradiation device at an energy amount of 1 J / cm 2, and then, it was vertically cured at 170 ° C./60 minutes in a hot-air circulation type drying furnace, and completely cured. Subsequently, the amount of concave portions on the through-holes was confirmed using a surface roughness measuring instrument SE-700 (manufactured by Kosaka Shusho).

(Assessment Methods)

○: The maximum recessed portion on the through hole is 5 µm or less.

△: The maximum recessed portion on the through-hole exceeds 5 µm.

<Evaluation of opening pattern formation>

The substrate provided with the resin layer obtained above was irradiated with light of a negative pattern shape having an opening design size of 100 µm with ORC's HMW680GW (metal halide lamp, scattered light). The light irradiation amount was set as described in Tables 1 to 3 below with reference to the exothermic peak temperature by DSC. Subsequently, heat treatment was performed for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. Subsequently, the substrate was immersed in a 35 wt.% Aqueous solution of 3 wt% TMAH / 5 wt% ethanolamine to develop for 3 minutes, and evaluation of developability and patterning was performed according to the following criteria. The obtained results are shown in Tables 1 to 3.

(Assessment Methods)

◎: It is possible to develop a sodium carbonate aqueous solution instead of the TMAH / 5wt% ethanolamine mixed aqueous solution. There is no damage by the developer on the surface of the light irradiation portion, and the developing residue is not visible in the non-irradiation portion

(Circle): The surface of the light irradiation part has no damage by a developer, and the developing residue is not visible in the non-irradiation part.

×: The development residue was confirmed in the unirradiated portion. Or, the status of the unexplored department could not be done

××: A state in which both the light irradiation part and the unirradiated part are completely dissolved

×××: 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 ORMW's HMW680GW (metal halide lamp, scattered light) in a negative pattern pattern with a design value of line / space = 100/100 μm. The light irradiation amount was set as described in Tables 1 to 3 below with reference to the exothermic peak temperature by DSC. Subsequently, heat treatment was performed for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. Subsequently, the substrate was immersed in a 3 wt% TMAH / 5wt% ethanolamine mixed aqueous solution at 35 ° C for 3 minutes to develop, and evaluation was performed according to the following criteria for a line-shaped pattern having a obtained design value of 100 µm. The obtained results are shown in Tables 1 to 3.

(Assessment Methods)

(Circle): The line top length was 100 micrometers, and the bottom length was 100 micrometers, and the pattern according to a design value was obtained.

(Triangle | delta): The top length of a line was 100 micrometers, and the bottom length became 60 micrometers or more and less than 100 micrometers, and a little undercut was seen.

X: The top length of the line was 100 µm, and the bottom length was less than 60 µm, and large undercuts were seen in the bottom.

(Dismeer resistance)

For the substrates produced in the same manner as the substrates for which the formation of the opening pattern was evaluated, ultraviolet irradiation was performed with an ORC ultraviolet irradiation device at an energy amount of 1 J / cm 2, and then in Tables 1 to 3 in a hot air circulation type drying furnace. Cured for 60 minutes at the described post-curing temperature (post-curing). Then, laser processing was performed on the light irradiation surface. The light source was processed with a CO ₂ laser (Hitachi Via Mechanics, light source 10.6 μm). It evaluated according to the following criteria. In order to cover the superiority of workability, laser processing was performed under the same conditions.

The target for the machining diameter is 65 µm top diameter / 50 µm bottom.

Condition: Aperture (mask diameter): 3.1 mm / pulse width 20 μsec / output 2 W / frequency 5 kHz / shot count: 3 burst shots

The laser-processed substrate was further subjected to a desmear treatment with an aqueous permanganic acid desmear solution (wet method). As an evaluation of the desmear resistance, the surface roughness of the substrate surface and the state around the laser opening were evaluated according to the following criteria. To confirm the surface roughness, each surface roughness Ra was measured by a laser microscope VK-8500 (Keyence Co., Ltd., measuring magnification 2000 times, Z-axis direction measuring pitch 10 nm). The laser aperture was observed by an optical microscope.

About chemicals (Rom & Haas)

Swell MLB-211 temperature 80 ℃ / hour 10 minutes

Permanganic acid MLB-213 Temperature 80 ° C / hour 15 minutes

Reduced MLB-216 temperature 50 ° C / hour 5 minutes

About evaluation method

◎: The surface roughness Ra after desorption of permanganic acid is less than 0.1 µm, and the difference from the diameter of the machining after laser processing is 2 µm or less.

(Circle): The surface roughness Ra after despermation of permanganic acid is 0.1-0.3 micrometers or less, and the difference with the processing diameter after laser processing is 2-5 micrometers.

X: The surface roughness Ra after desorption of permanganic acid exceeds 0.3 mu m, and the difference from the machining diameter after laser machining is 5 mu m or more.

<Evaluation of warpage after curing>

A dry film having a thickness of 20 µm, produced by the method described in the production section of the dry film, was cut into squares of 50 mm × 50 mm in size using a vacuum laminator MVLP-500 manufactured by Meikki Co., Ltd. It was laminated. Lamination conditions were performed at a temperature of 80 ° C and a pressure of 5 kg / cm 2/60 seconds. Subsequently, the copper foil provided with the thermosetting resin layer was irradiated with an entire surface solid exposure with ORMW HMW680GW (metal halide lamp, scattered light). About the light irradiation amount, the exothermic peak temperature by DSC was set as described in Tables 1-3. Subsequently, the substrate was heated for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. Moreover, UV irradiation was performed with ORC's ultraviolet irradiation device at an energy amount of 1 J / cm 2, and subsequently cured in a hot-air circulating drying furnace at 170 ° C./60 minutes to obtain a copper foil having a thermosetting resin composition on one side. Then, as an evaluation of the warpage state of the obtained cured product, the amount of warpage at four ends was measured with a nogis.

(Assessment Methods)

(Circle): Warping is hardly seen. The bending amount of the maximum bending portion among the four ends is less than 5 mm

○: A slight deflection was observed. The bending amount of the maximum bending portion among the four ends is 5 mm or more and less than 20 mm

△: The bending amount of the maximum bending portion among the four ends was 20 mm or more.

X: The cured product contracted into a cylindrical shape. Nogisu was unable to measure the amount of warpage at the end.

<CTE measurement>

A dry film having a thickness of 40 µm was produced according to the method described in the production section of the dry film. Thereafter, a dry film was laminated on the glossy surface side of the 18 µm copper foil using a vacuum laminator MVLP-500 manufactured by Meiki. Lamination conditions were performed at a temperature of 80 ° C and a pressure of 5 kg / cm 2/60 seconds. Subsequently, the entire surface solid exposure was performed with ORMW HMW680GW (metal halide lamp, scattered light). The light irradiation amount was set as described in Tables 1 to 3 below with reference to the exothermic peak temperature by DSC. Subsequently, heat treatment was performed for 60 to 80 minutes under the temperature conditions described in Tables 1 to 3. Then, ultraviolet irradiation was performed with ORC's ultraviolet irradiation device at an energy amount of 1 J / cm 2, and then completely cured at 170 ° C./60 minutes in a hot air circulation type drying furnace. Then, it peeled from the copper foil, and the resin composition of an Example and a comparative example was obtained. Thereafter, the obtained resin composition was cut into a rectangle having a width of 3 mm and a length of 10 mm, and the CTE measurement (thermal expansion coefficient) was evaluated by the TMA method (tensile method) described in JIS-C-6481. The temperature increase rate was 5 ° C / min, and the coefficient of thermal expansion of Tg or less was evaluated. As for the thermal expansion coefficient, the average thermal expansion coefficient of the temperature range 25 degreeC-100 degreeC, and the unit was made into ppm.

The obtained CTE values are shown in Tables 1 to 3.

<Evaluation of cold / heat cycle characteristics>

The printed wiring board subjected to the desmear treatment of permanganic acid as described above was further plated under conditions of 0.5 µm nickel and 0.03 µm gold plating using commercially available electroless nickel plating baths and electroless gold plating baths. Gold plating treatment was performed. The obtained printed wiring board was evaluated for cold-heat cycle characteristics. The treatment conditions were 30 minutes at -65 ° C and 30 minutes at 150 ° C for 1 cycle, and after 2000 cycles by applying heat history, the state of the surface and the periphery of the pattern layer was observed with an optical microscope and cracked according to the following criteria. Was evaluated. The number of observation patterns was 100 holes. The obtained results are shown in Tables 1 to 3 below.

(Assessment Methods)

◎ ○: No crack occurs on the surface and periphery of the pattern layer

◎: Crack incidence of the periphery of the pattern layer was less than 10%

○: 10% or more and less than 30% crack incidence in the periphery of the pattern layer

(Triangle | delta): The crack generation rate of the peripheral part of a pattern layer is 30% or more

<Method for measuring refractive index of thermally reactive compound, maleimide compound, and alkali developable resin>

Measuring device: Abbe refractometer

Measurement conditions: Wavelength 589.3nm, temperature 25 ° C

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

(+ Polymer resin)

(Comparative example)

Each component in Tables 1-3 is as follows.

(Thermoreactive compound)

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

※ HP-4032: Naphthol type epoxy (equivalent to 150g / eq), DIC company

※ HP-7200 H60: Dicyclopentadiene type epoxy (equivalent 265g / eq), DIC company is dissolved in cyclohexanone. Solid content 60%

(Maleimide compound)

※ UVT-302: acrylic polymer having a maleimide group on the side chain (equivalent to 320 g / eq), Toa Gosei

(Alkali developable resin)

※ HF-1M H60: Phenolic novolac (hydroxyl equivalent: 105 g / eq), and May and Kasei are dissolved in cyclohexanone. Solid content 60%

MEH-7851M H60: Biphenyl / phenol novolac (a hydroxyl group equivalent of 210 g / eq), and May and Kasei were dissolved in cyclohexanone. Solid content 60%.

※ John Krill 586 H60: Styrene acrylic acid copolymer resin, Mw = 3100, solid content acid value = 108 mgKOH / g, Johnson Polymer Co. was dissolved in cyclohexanone. Solid content 60%

※ John krill 68 H60: Styrene acrylic acid copolymer resin, Mw = 10000, acid value 195 mgKOH / g, Johnson Polymer Co., Ltd.

(Photobase generator)

※ Irg369: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, BASF Japan

※ WPBG-140: 1- (anthraquinone-2-yl) ethyl imidazole carboxylate, Wako Pure Chemical Industries, Ltd.

(Polymer resin)

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

(Weapon filler)

※ SO-C2: Spherical silica D50 = 0.5㎛, Refractive index = 1.4 to 1.5, Admatex company, specific gravity: 2.2g / cm3

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

※ Higillit H-42M: Aluminum hydroxide D50 = 1.0㎛, Refractive index = 1.65, Showa Denkosa, specific gravity: 2.4g / cm3

※ B-30: Barium sulfate, D50 = 0.3㎛, Refractive index = 1.64, Sakai Chemicals, Specific Gravity: 4.3g / cm3

(Other)

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

※ DPHA: Dipentaerythritol hexaacrylate_Nippon Kayakusa

※ IRG-184: 1-hydroxycyclohexyl-phenylketone_Shiba Japan

As shown in Tables 1 to 3, in Examples 1 to 19, it was confirmed that pattern formation by alkali development was possible, and that the obtained pattern had excellent curing properties and cold heat cycle properties.

Moreover, in Examples 15, 16, etc., by blending a polymer resin, the melt viscosity of the thermosetting resin composition increases, and the resin fluidity of the through-hole portion can be suppressed during heating after exposure. As a result, a flat substrate with no concave portion visible on the through hole can be produced.

In addition, in Examples 18 and 19, even when the content of the inorganic filler was considerably high, good curing properties were obtained during the cold heat cycle.

On the other hand, in the photo-radical composition of Comparative Example 4, it was difficult to form a pattern by alkali development. Also, the line shape was poor. Moreover, the curvature after hardening was also large, and the hardenability at the time of a cold heat cycle was also inferior.

<DSC measurement immediately after light irradiation>

The substrate provided with the resin layer obtained in Example 1 was irradiated with light in a negative pattern with ORMW HMW680GW (metal halide lamp, scattered light). Each substrate was irradiated with a pattern with an irradiation amount of 1000 mJ / cm 2. After the light irradiation, the resin layer was scraped off from the substrate, and immediately in a DSC-6200 manufactured by Seiko Instruments, the temperature was raised to 30 to 300 ° C at a heating rate of 5 ° C / min. Did. Moreover, DSC measurement was similarly performed about the cured layer containing the thermosetting resin composition immediately after ultraviolet irradiation and before post-cure.

2 is a DSC chart of an unirradiated portion, a light irradiated portion having an irradiation amount of 1000 mJ / cm 2, and a light irradiating portion irradiated with UV at 1000 mJ / cm 2 after being irradiated with an irradiation amount of 1000 mJ / cm 2. In the light irradiation part of Example 1, the peak shifted to the low temperature side by light irradiation.

(Comparative Example 5)

A double-sided printed wiring substrate having a plate thickness of 0.4 mm with a circuit thickness of 15 µm was prepared, and pretreatment was performed using CZ-8100 manufactured by Mack. Thereafter, the brand name PSR-4000G23K (Daiyo Inki Seijo Co., Ltd., photocurable resin composition containing an alkali developing resin having an epoxy acrylate structure) was screen-printed and applied to dryness to 20 μm. . Subsequently, after drying at 80 ° C / 30 minutes in a hot-air circulation type drying furnace, light was irradiated with an ORC HMW680GW (metal halide lamp, scattered light) in a negative pattern pattern with an irradiation amount of 300 mJ / cm 2. Thereafter, it was developed for 60 seconds with an aqueous 1 wt% sodium carbonate solution, and then heat-treated at 150 ° C. for 60 minutes using a hot air circulation type drying furnace to obtain a patterned cured coating film.

Then, the desmear resistance was evaluated like Example 2 above. As a result, the desmear resistance was "x".

Claims (5)

Step (A) of forming a resin layer containing a thermosetting resin composition on a substrate,
Step (B) of curing a light irradiation part by activating a photobase generator included in the resin layer by irradiating light in a negative pattern shape,
After the step (B), the step (B1) of heating the resin layer, and
It is a pattern formation method including the process (C) which forms a negative pattern layer by removing an unirradiated part by image development after process (B1),
As the thermosetting resin composition,
Alkali developable resin,
Thermally reactive compounds,
Inorganic fillers, and
Containing a photobase generator,
The mixing ratio of the inorganic filler is 50% by mass or more and 80% by mass or less of the total solid content of the thermosetting resin composition,
A pattern formation method characterized by using an alkali-developable thermosetting resin composition that enables the formation of a negative pattern by alkali development by addition reaction of the alkali-developable resin and the heat-reactive compound by selective light irradiation. . Alkali developable resin,
Thermally reactive compounds,
Inorganic fillers, and
Containing a photobase generator,
The mixing ratio of the inorganic filler is 50% by mass or more and 80% by mass or less of the total solid content of the thermosetting resin composition,
An alkali-developable thermosetting resin composition capable of forming a negative pattern by alkali development by addition reaction of the alkali-developable resin and the heat-reactive compound by selective light irradiation, the pattern forming method according to claim 1 An alkali-developing type thermosetting resin composition, which is used for a. The alkali-developable thermosetting resin composition according to claim 2, wherein the inorganic filler has an average particle diameter of 1 µm or less. The exothermic peak in DSC measurement by light irradiation, or the exothermic initiation temperature in DSC measurement of the alkali-developed thermosetting resin composition irradiated with light is not irradiated. The exothermic peak in DSC measurement of the alkali developing type thermosetting resin composition of the undeveloped alkali developing type, which is lower than the exothermic starting temperature in DSC measurement of, or irradiated with light, of the alkali developing type thermosetting resin composition. An alkali-developable thermosetting resin composition characterized by being lower than the temperature. A printed wiring board comprising the pattern layer comprising the alkali-developable thermosetting resin composition according to any one of claims 2 to 4.

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