WO2017170958A1

WO2017170958A1 - Curable resin composition, dry film, cured product and printed wiring board

Info

Publication number: WO2017170958A1
Application number: PCT/JP2017/013453
Authority: WO
Inventors: 千穂植田; 岡田　和也; 信人伊藤
Original assignee: 太陽インキ製造株式会社
Priority date: 2016-03-31
Filing date: 2017-03-30
Publication date: 2017-10-05
Also published as: CN109073969A; JPWO2017170958A1; TWI745366B; KR20180129868A; JP6967508B2; CN109073969B; TWI793795B; TW202204435A; JP2022009428A; TW201809028A; KR102369508B1

Abstract

Provided are: a curable resin composition which is capable of providing a cured product that exhibits excellent crack resistance when a high temperature load is applied thereto; and the like. A curable resin composition which contains (A) an alkali-soluble resin, (B) a thermosetting component, (C) a compound having an ethylenically unsaturated group, (D) a photopolymerization initiator and (E) a surface-treated inorganic filler, and which is characterized in that: the inorganic filler (E) has an average particle diameter of 100 nm to 1 μm, and comprises a reactive group that is able to react with at least one of the alkali-soluble resin (A), the thermosetting component (B) and the compound (C) having an ethylenically unsaturated group; an epoxy resin having an epoxy equivalent weight of 300 g/eq. or less is contained as the thermosetting component (B); and with respect to a cured product obtained from the resin composition and having a thickness of 40 μm, the maximum value of Tan δ as determined by dynamic viscoelasticity measurement performed at a frequency of 1 Hz at a heating rate of 5°C/min from 25°C to 300°C is 0.15 or less.

Description

Curable resin composition, dry film, cured product and printed wiring board

The present invention relates to a curable resin composition, a dry film, a cured product, and a printed wiring board.

In recent years, with the rapid progress of semiconductor components, electronic devices tend to be lighter, thinner, smaller, higher performance, and multifunctional. Following this trend, miniaturization and multi-pin semiconductor packages have been put into practical use.

Specifically, instead of IC packages called QFP (Quad Flat Pack Package), SOP (Small Outline Package), etc., BGA (Ball Grid Array), CSP (Chip Scale Package), etc. IC package called is used. In recent years, FC-BGA (Flip Chip Ball Grid Array) has been put to practical use as an IC package with higher density. A printed wiring board (also referred to as a package substrate) used in such an IC package has a narrow SRO (Solder Resist Opening) pitch and is formed close to each other. It is thin and thin, and cracks are likely to occur.

In the future, the solder resist film will continue to become thinner, but the heat generated by the mounted components tends to increase. Therefore, crack resistance at higher temperatures is required. In particular, parts for in-vehicle use have a high current density and are likely to be high in temperature, and therefore are assumed to be used in an environment where cracks are likely to occur.

Conventionally, as a method for improving crack resistance, for example, a photocurable resin composition containing an acid-modified vinyl group-containing epoxy resin, an elastomer, a photopolymerization initiator, a diluent and a curing agent has been disclosed (for example, Patent Document 1). ). Patent Document 1 discloses that the crack resistance is improved by an elastomer.

However, with the above means alone, satisfactory results could not be obtained when further resistance to cracking was required in the future.

Japanese Patent Laid-Open No. 11-240930

Accordingly, an object of the present invention is to provide a curable resin composition capable of obtaining a cured product having excellent crack resistance when a high temperature load is applied, a dry film having a resin layer obtained from the composition, the composition or the dry composition. It is providing the hardened | cured material of the resin layer of a film, and the printed wiring board which has this hardened | cured material.

Various stresses are applied to the solder resist used in the IC package, and by accumulating these stresses, the stress that cannot be withstood is released as cracks.
Stress mainly consists of (1) stress generated by thermal linear expansion (CTE) difference between solder resist and peripheral members (copper, base material, etc.), and (2) gas generated by thermal history during packaging (solder resist And (3) stress (strain) generated by the crosslinking reaction in the solder resist due to the thermal history after mounting. Conventionally, in order to suppress cracks, a method of blending an elastomer or the like into a solder resist to relieve stress, or a method of reducing the solder resist to a high glass transition temperature (Tg) and a low CTE is based on the stress generated in (1) above. It was effective against this.
However, in recent years, IC packages for in-vehicle use are exposed to a high temperature environment, and the stress due to (2) and (3) becomes larger due to the influence of the temperature environment, thermal history, and materials used, and the stress is infinite. For this reason, there is a case where the generated stress cannot be prevented by simple stress relaxation, high Tg, and low CTE.
Therefore, the inventors originally had a modulus of elasticity at Tg or higher after curing, in addition to the means of lowering the thermal expansion coefficient after curing, with respect to the solder resist whose thermal expansion coefficient and elastic modulus change due to heat. Regarding the characteristics to be lowered, it was found that DMA viscoelasticity evaluation considering the force (viscosity) proportional to the displacement speed is necessary. The behavior of the viscous component by DMA is a very important physical property for predicting the characteristics of a solder resist whose Tg is lower than the melting temperature of the solder.
In particular, the change behavior of Tan δ obtained by DMA has an important meaning, and a material having a large maximum value of the Tan δ peak (for example, a material having physical properties as shown in FIG. 1) depends on mounting electronic components. A material that is flexible and flexible for the purpose of relieving mechanical stress is considered to be suitable. On the other hand, a material having a small maximum value of Tanδ peak (for example, a material having physical properties as shown in FIG. 2). Found that it is rigid and less temperature dependent so as not to lose stress.
In the future IC package, it is necessary to consider the latter method, that is, if the Tan δ value of DMA is 0.15 or less, the viscosity component in the cured product is small. It is possible to suppress the reaction from proceeding in part or causing a change in physical properties due to sparse cross-linking structure due to molecular motion in the vicinity of Tg. That is, since there is little temperature dependence and there are few physical property changes before and after Tg, the stress which generate | occur | produces by the physical property change by a high temperature heat history can be reduced. Therefore, if the value of Tan δ of DMA is 0.15 or less, it is effective not only for the stress of (1) above but also for the stress suppression of (3).
In order to reduce Tan δ of the cured product, the average particle diameter of the inorganic filler is set to a specific range, a specific reactive group is introduced into the inorganic filler, and the epoxy equivalent of the epoxy resin is within a specific value range. From the viewpoint that the cross-linking becomes dense, it has been found that it is effective for the stress (2).

That is, the curable resin composition of the present invention comprises (A) an alkali-soluble resin, (B) a thermosetting component, (C) a compound having an ethylenically unsaturated group, (D) a photopolymerization initiator, and (E ) A resin composition containing a surface-treated inorganic filler, wherein the (E) surface-treated inorganic filler has an average particle size of 100 nm to 1 μm, and (A) the alkali-soluble resin, It has a reactive group capable of reacting with at least one of the (B) thermosetting component and the (C) compound having an ethylenically unsaturated group, and as the (B) thermosetting component, an epoxy equivalent of 300 g / eq. In the case of a dynamic viscoelasticity measurement from 25 ° C. to 300 ° C. under a condition of a frequency of 1 Hz and a temperature rising rate of 5 ° C./min in a cured product having a thickness of 40 μm obtained from the resin composition, including the following epoxy resin The maximum value of Tan δ is 0.15 or less.

The curable resin composition of the present invention has an epoxy equivalent of 300 g / eq. The following epoxy resins preferably include (B-1) a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower and (B-2) a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower.

In the curable resin composition of the present invention, the compounding amount of the compound (C) having an ethylenically unsaturated group is preferably less than 20 parts by mass with respect to 100 parts by mass of the (A) alkali-soluble resin.

In the curable resin composition of the present invention, the blending amount of the (E) surface-treated inorganic filler is preferably 35% by mass or more in the solid content of the curable resin composition.

The curable resin composition of the present invention has a storage elastic modulus of 150 ° C. when a dynamic viscoelasticity measurement is performed from 25 ° C. to 300 ° C. under the conditions of a frequency of 1 Hz and a heating rate of 5 ° C./min. It is preferably 1 GPa or more and the change rate of the storage elastic modulus from 25 ° C. to 150 ° C. is within 70%.

In the curable resin composition of the present invention, CTEα2 of the cured product is preferably 110 ppm or less.

In the curable resin composition of the present invention, the Tg of the cured product is preferably 160 ° C. or higher.

The curable resin composition of the present invention is preferably used for forming a solder resist.

The dry film of the present invention is characterized by having a resin layer obtained by applying the curable resin composition to the film and drying it.

The cured product of the present invention is obtained by curing the curable resin composition or the resin layer of the dry film.

The printed wiring board of the present invention is characterized by having the cured product.

ADVANTAGE OF THE INVENTION According to this invention, the curable resin composition which can obtain the hardened | cured material excellent in the crack tolerance when high temperature load is applied, the dry film which has a resin layer obtained from this composition, this composition, or this dry film The cured product of the resin layer and a printed wiring board having the cured product can be provided.

FIG. 1 is an image diagram showing storage elastic modulus, loss elastic modulus, and Tan δ of a cured product having a large maximum value of Tan δ peak. FIG. 2 is an image diagram showing storage elastic modulus, loss elastic modulus, and Tanδ of a cured product having a small maximum value of Tanδ peak.

The curable resin composition of the present invention is such that the maximum value of Tan δ of the cured product is 0.15 or less in the temperature range of 25 to 300 ° C. With such physical properties, the temperature of the cured film is low. Stable crack resistance can be obtained even when exposed to high temperatures.
In the present specification, unless otherwise specified, the physical properties of the cured product such as Tan δ are further provided with a high-pressure mercury lamp after irradiating the resin layer after drying the resin composition with ultraviolet rays at about 500 mJ / cm ^2. It means physical properties of a cured product having a thickness of 40 μm obtained by irradiating with an exposure amount of 1 J / cm ^{2 in} a UV conveyor furnace and then heating at 160 ° C. for 60 minutes to completely cure the resin layer. Ultraviolet rays are electromagnetic waves having a wavelength of 10 to 400 nm. Tan δ is a value obtained by dividing the loss elastic modulus measured by dynamic viscoelasticity measurement by the storage elastic modulus, that is, loss tangent (= loss elastic modulus / storage elastic modulus). The measured physical properties such as Tan δ are based on a chart obtained by measuring from 25 ° C. to 300 ° C. under the conditions of a frequency of 1 Hz and a heating rate of 5 ° C./min.

In order to obtain a cured product having a small Tan δ (= loss elastic modulus / storage elastic modulus), the loss elastic modulus (viscous component) is decreased, the storage elastic modulus (elastic component) is increased, or both are performed. In other words, the elastic component may be increased as much as possible in the cured product rather than the viscous component.
Means for setting the maximum value of Tanδ to 0.15 or less is not particularly limited, but the average particle diameter is 100 nm to 1 μm, and (A) an alkali-soluble resin, (B) a thermosetting component, and (C) ethylene. A surface-treated inorganic filler having a reactive group capable of reacting with at least one compound having a polymerizable unsaturated group, and (B) an epoxy equivalent of 300 g / eq. It is effective to use the following epoxy resin.
(E) When the average particle diameter of an inorganic filler is 1 micrometer or less, the surface area per volume is large and it can have many said reactive groups. On the other hand, when the average particle size is 100 nm or more, the shrinkage of the cured product is suppressed and the crack resistance is improved.
Moreover, (B) Epoxy equivalent is 300 g / eq. As a thermosetting component. By including the following epoxy resin, the number of cross-linking points with (A) alkali-soluble resin increases, so that the cross-linking density increases and unreacted (A) alkali-soluble resin and the like can be reduced. For this reason, the maximum value of Tan δ is reduced, the cured product is less likely to undergo a sudden change in elastic modulus at a high temperature around 150 ° C., and crack resistance is further improved.
Therefore, the above (E) inorganic filler and epoxy equivalent are 300 g / eq. By curing a composition containing the following epoxy resin, the maximum value of Tan δ of the cured product becomes 0.15 or less in the range of 25 to 300 ° C., and stable crack resistance can be obtained. It is preferable that the maximum value of Tan δ is 0.13 or less because crack resistance is further improved.

Also, as will be described later, Tanδ of the cured product can be reduced by reducing the blending amount of the compound (C) having an ethylenically unsaturated group.

When the maximum value of Tan δ of the cured product is large, when the cured product is exposed to a high temperature, the viscosity component in the cured product easily moves and the physical properties change greatly. However, if the maximum value of Tan δ is 0.15 or less, For example, even when a high temperature state close to the Tg of the cured product is reached, the viscosity component hardly moves and the physical property change is small, and the occurrence of cracks can be suppressed.

Further, the storage elastic modulus at 150 ° C. of the cured product of the curable resin composition of the present invention may be any value as long as the maximum value of Tan δ of the cured product is 0.15 or less, but is 1 GPa or more. Is preferred. More preferably, it is 2 GPa or more. When the storage elastic modulus is 1 GPa or more, resistance of the cured product to the water vapor pressure inside the package is improved, and crack resistance and insulation reliability are improved.
Conventionally, in order to obtain crack resistance at high temperatures, it has been preferred that the change in storage elastic modulus is large for stress absorption.
However, in the curable resin composition of the present invention, conversely, the rate of change in the storage elastic modulus is reduced to maintain the toughness even at high temperatures, thereby suppressing the generation of stress and the generation of cracks. It is.
In the present invention, it is preferable that the change rate of the storage elastic modulus is small, and the change rate of the storage elastic modulus at 25 ° C. to 150 ° C. is preferably within 70%. More preferably, it is within 65%.

The CTEα2 of the cured product of the curable resin composition of the present invention is preferably 110 ppm or less, more preferably 100 ppm or less. As CTEα2 is smaller, changes in physical properties can be reduced even at high temperatures.

The curable resin composition of the present invention preferably has a Tg (glass transition temperature) of 160 ° C. or higher. More preferably, it is 165 ° C. or higher. The higher the Tg, the less the change in physical properties at high temperatures.

Hereinafter, each component of the curable resin composition of the present invention will be described. In addition, in this specification, (meth) acrylate is a term which generically refers to acrylate, methacrylate and a mixture thereof, and the same applies to other similar expressions.

[(A) Alkali-soluble resin]
(A) The alkali-soluble resin is, for example, a resin containing one or more alkali-soluble groups among phenolic hydroxyl groups, thiol groups, and carboxyl groups, preferably a compound having two or more phenolic hydroxyl groups, a carboxyl group-containing resin. , A compound having a phenolic hydroxyl group and a carboxyl group, and a compound having two or more thiol groups. (A) As the alkali-soluble resin, a carboxyl group-containing resin or a phenolic hydroxyl group-containing resin can be used, but from the viewpoint of reactivity with (B) a thermosetting component and (E) an inorganic filler, a carboxyl group-containing resin. Is preferred.

(A) The alkali-soluble resin having a smaller weight average molecular weight is preferred because the proportion of alkali-soluble groups in the alkali-soluble resin increases and the crosslink density of the cured product increases. (A) The alkali-soluble resin preferably has a weight average molecular weight of 10,000 or less in terms of polystyrene when measured by weight average molecular weight (Mw) gel permeation chromatography (GPC).

(A) It is preferable that alkali-soluble resin has an ethylenically unsaturated group in a molecule | numerator other than a carboxyl group from a viewpoint of developability, photocurability, and developability. In addition, you may use only carboxyl group-containing resin which does not have an ethylenically unsaturated group. As the ethylenically unsaturated group, those derived from acrylic acid, methacrylic acid or derivatives thereof are preferable.
Specific examples of the carboxyl group-containing resin include compounds listed below (which may be either oligomers or polymers).

(1) A difunctional or higher polyfunctional epoxy resin is reacted with (meth) acrylic acid, and the hydroxyl group present in the side chain is dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. A carboxyl group-containing photosensitive resin to which is added. Here, the bifunctional or higher polyfunctional epoxy resin is preferably solid.

(2) A carboxyl group in which a polyfunctional epoxy resin obtained by epoxidizing the hydroxyl group of a bifunctional epoxy resin with epichlorohydrin is reacted with (meth) acrylic acid, and a dibasic acid anhydride is added to the resulting hydroxyl group. Contains photosensitive resin. Here, the bifunctional epoxy resin is preferably solid.

(3) An epoxy compound having two or more epoxy groups in one molecule is combined with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, and (meth) acrylic acid or the like. Reaction with a saturated carboxylic acid containing monocarboxylic acid, the resulting reaction product has many alcoholic hydroxyl groups such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic anhydride. A carboxyl group-containing photosensitive resin obtained by reacting a basic acid anhydride.

(4) Two or more per molecule such as bisphenol A, bisphenol F, bisphenol S, novolac type phenol resin, poly-p-hydroxystyrene, condensate of naphthol and aldehydes, condensate of dihydroxynaphthalene and aldehydes, etc. Reaction obtained by reacting an unsaturated group-containing monocarboxylic acid such as (meth) acrylic acid with a reaction product obtained by reacting a compound having a phenolic hydroxyl group with an alkylene oxide such as ethylene oxide or propylene oxide A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.

(5) An unsaturated group-containing monocarboxylic acid is reacted with a reaction product obtained by reacting a compound having two or more phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate. A carboxyl group-containing photosensitive resin obtained by reacting the resulting reaction product with a polybasic acid anhydride.

(6) Carboxy group-containing photosensitivity obtained by copolymerization of unsaturated carboxylic acid such as (meth) acrylic acid and unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, and isobutylene. resin.

(7) A carboxyl group obtained by reacting a difunctional acid such as adipic acid, phthalic acid or hexahydrophthalic acid with a polyfunctional oxetane resin as described later and adding a dibasic acid anhydride to the resulting primary hydroxyl group Contains polyester resin.

(8) A carboxyl group-containing photosensitive resin obtained by adding a compound having a cyclic ether group and a (meth) acryloyl group in one molecule to the carboxyl group-containing resin such as (1) to (7) described above.

As a carboxyl group-containing resin having an ethylenically unsaturated group (also referred to as a carboxyl group-containing photosensitive resin), the main chain derived from a phenol resin or an epoxy resin is separated from the ethylenically unsaturated group of the side chain. Preferably there is. In other words, when an ethylenically unsaturated group is introduced into the side chain, it is preferable to introduce a chain extension structure so that a certain distance is generated between the main chain and the ethylenically unsaturated group. Such a structure is preferable for improving the reactivity between side chain ethylenically unsaturated groups. As the carboxyl group-containing resin having a chain extension structure and an ethylenically unsaturated group, for example, the carboxyl group-containing resins described in (3), (4), (5), and (8) are preferable.

(A) The acid value of the alkali-soluble resin is preferably 40 to 150 mgKOH / g. When the acid value of the carboxyl group-containing resin is 40 mgKOH / g or more, alkali development is improved. Moreover, a normal hardened | cured material pattern can be drawn easily by making an acid value into 150 mgKOH / g or less. More preferably, it is 50 to 130 mgKOH / g.

(A) The blending amount of the alkali-soluble resin is, for example, 15 to 60% by mass, preferably 20 to 60% by mass, based on the total solid content of the composition excluding the solvent. By setting the content to 15% by mass or more, preferably 20% by mass or more, the coating film strength can be improved. Further, when the content is 60% by mass or less, viscosity becomes appropriate and workability is improved. More preferably, it is 30 to 50% by mass.

[(B) Thermosetting component]
The curable resin composition of the present invention has an epoxy equivalent of 300 g / eq. The following epoxy resin is included, and 200 g / eq. Is more preferable from the viewpoint of improving the crosslink density and further improving the crack resistance. It is as follows.

The epoxy resin is not particularly limited as long as the epoxy equivalent is satisfied. Epoxy resin includes epoxidized vegetable oil; bisphenol A type epoxy resin; hydroquinone type epoxy resin; bisphenol type epoxy resin; thioether type epoxy resin; brominated epoxy resin; novolac type epoxy resin; biphenol novolac type epoxy resin; Resin; Hydrogenated bisphenol A type epoxy resin; Glycidylamine type epoxy resin; Hydantoin type epoxy resin; Alicyclic epoxy resin; Trihydroxyphenylmethane type epoxy resin; Alkylphenol type epoxy resin (for example, bixylenol type epoxy resin); Type epoxy resin; bisphenol S type epoxy resin; bisphenol A novolak type epoxy resin; tetraphenylolethane type epoxy resin; Diglycidyl phthalate resin; Tetraglycidyl xylenoyl ethane resin; Naphthalene group-containing epoxy resin; Epoxy resin having dicyclopentadiene skeleton; Triphenylmethane type epoxy resin; Epoxy resin having silsesquioxane skeleton; Examples include acrylate copolymer epoxy resins; cyclohexyl maleimide and glycidyl methacrylate copolymer epoxy resins; epoxy-modified polybutadiene rubber derivatives; CTBN-modified epoxy resins. An epoxy resin can be used individually by 1 type or in combination of 2 or more types. Among these, novolac type epoxy resins, bisphenol type epoxy resins, bixylenol type epoxy resins, biphenol type epoxy resins, biphenol novolac type epoxy resins, naphthalene type epoxy resins, epoxy resins having a silsesquioxane skeleton, and triphenylmethane At least one of the type epoxy resins is preferred.

Epoxy equivalent is 300 g / eq. The following commercially available epoxy resins include EXP7241 (triphenylmethane type epoxy resin), HP6000 (epoxy resin having a naphthalene group), Epicron N-740 (phenol novolac type epoxy resin) manufactured by DIC, Nippon Steel & Sumikin Chemical Co., Ltd. Examples include Epototo YDC-1312 (hydroquinone type epoxy resin) and YSLV-80XY (bisphenol F type epoxy resin).

Since the composition of the present invention can increase the crosslink density, it is preferable that (B) a thermosetting component contains two or more polyfunctional epoxy resins from the viewpoint of lowering Tan δ. In this specification, “polyfunctional” means two or more functional groups. In addition, the composition of the present invention preferably contains (B-1) a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower as the (B) thermosetting component. B-2) It is preferable to include a mixture with a bifunctional or higher functional epoxy resin having a softening point exceeding 40 ° C. (B-1) By including a bifunctional or higher functional epoxy resin with a softening point of 40 ° C. or less, (E) it is possible to achieve high filling of inorganic fillers, resulting in low CTE and low Tan δ, and crack resistance in thermal cycle tests. Will improve. Further, (B-2) by including a bifunctional or higher functional epoxy resin having a softening point exceeding 40 ° C., the glass transition temperature (Tg) of the entire curable resin composition can be increased. As a result, heat resistance such as PCT resistance and reliability such as crack resistance in a thermal cycle test can be further improved. Here, the softening point means a value measured according to the method described in JIS K 7234.

(B-1) The bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower may be a known resin, but is preferably liquid at room temperature, for example. (B-1) Commercially available bifunctional or higher functional epoxy resins having a softening point of 40 ° C. or lower include, for example, Epicoat 834, 828 (manufactured by Mitsubishi Chemical Corporation), YD-128 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), 840, 850 Bisphenol A type epoxy resin such as DIC (manufactured by DIC), 806, 807 (manufactured by Mitsubishi Chemical), YDF-170 (manufactured by Nippon Steel & Sumikin Chemical), 830, 835, bisphenol F such as N-730A (manufactured by DIC) Type epoxy resin, mixture of bisphenol A and bisphenol F such as ZX-1059 (manufactured by Nippon Steel & Sumikin Chemical), hydrogenated bisphenol such as YX-8000 and 8034 (manufactured by Mitsubishi Chemical) ST-3000 (manufactured by Nippon Steel & Sumikin Chemical) Type A epoxy resin, Nippon Kayaku's RE-306CA90, Dow Chemical's DEN431, DEN438 and other novola Click type epoxy resin, DIC Corporation of EPICLON HP-820, etc. alkylphenol type epoxy resin and the like.

The content of the (B-1) bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower is such that (B-1) the softening point is 40 ° C. or lower with respect to 1 equivalent of the alkali-soluble group of the alkali-soluble resin. The epoxy group of the bifunctional or higher functional epoxy resin is preferably in the range of 0.2 to 1.8 equivalents. (B-1) The softening point of the bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower is preferably −80 to 30 ° C., more preferably −70 to 20 ° C. Effective in reducing Tan δ (E) In the high filling of inorganic fillers, the use of a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower can increase the degree of freedom in compounding design and increase the adhesive strength. be able to.

(B-2) Commercially available bifunctional or higher functional epoxy resins having a softening point exceeding 40 ° C. include, for example, ICTEP-S (softening point: 110 ° C.), TEPIC-H, N870, DIC manufactured by Nissan Chemical Co., Ltd. HP-7200 (softening point: 60 ° C), HP-4700 (softening point: 90 ° C), HP-4710 (softening point: 96 ° C), EXA-7241 (softening point: 70 ° C), manufactured by Mitsubishi Chemical Corporation YX-4000 (softening point: 105 ° C), NC-3000L (softening point: 52 ° C), NC-7000L (softening point: 86 ° C), CER-3000L (softening point: 93 ° C) manufactured by Nippon Kayaku Co., Ltd. EPPN-502H (softening point: 67 ° C.), Epototo YSLV-80XY (softening point: 80 ° C.) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., EPICLON-N660 (softening point: 61 to 69 ° C.) YDC-1312 (softening point: 140 ° C.), and the like.

(B-2) The softening point of a bifunctional or higher functional epoxy resin having a softening point exceeding 40 ° C. is preferably 50 ° C. or higher, and more preferably 60 ° C. or higher. In addition, the upper limit of the softening point in the (B-2) bifunctional or higher functional epoxy resin having a softening point exceeding 40 ° C. is not particularly limited, but is about 400 ° C. or lower. It is preferable that it is 80 degrees C or less from a viewpoint of the workability at the time of forming into a dry film.

The blending ratio of (B-1) a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or less and (B-2) an epoxy resin having a softening point of more than 40 ° C. is (B-1) the softening point is 40 ° C. or less. Equivalent ratio of epoxy group (b-1) of bifunctional or higher epoxy resin to (B-2) epoxy group (b-2) of bifunctional or higher epoxy resin having a softening point exceeding 60 ° C. (b-1) : (B-2) is preferably 3: 7 to 9: 1, more preferably 4: 6 to 8: 2. When the ratio of the epoxy group (b-1) is 3 to 9, it is possible to achieve both low Tanδ and high Tg.

Epoxy equivalent is 300 g / eq. As the following epoxy resin, it is particularly preferable to include a trifunctional or higher functional epoxy resin from the viewpoint of increasing the crosslinking density among the epoxy resins. The structure of the tri- or higher functional epoxy resin is not particularly limited as long as it is an epoxy resin having three or more epoxy groups. Among them, the epoxy equivalent is 200 g / eq. From the viewpoint of further increasing the crosslinking density. The following trifunctional or higher epoxy resins are more preferable.

As a specific example of a commercial product of an epoxy resin having a trifunctional or higher functional epoxy group, a product name of a trifunctional aminophenol type epoxy resin “jER-630” (manufactured by Mitsubishi Chemical Corporation), a product of a trifunctional triazine skeleton-containing epoxy resin The name “TEPIC-SP” (manufactured by Nissan Chemical Industries, Ltd.) The product name of trifunctional aromatic epoxy resin “Techmore VG3101” (manufactured by Printec Co., Ltd.) The product name of tetrafunctional aromatic epoxy resin “GTR-1800” (Japan) Kayaku Co., Ltd.), modified novolak epoxy resin trade name “EPICLON-N740” (DIC Corporation), dicyclopentadiene epoxy resin trade name “EPICLON-HP7200H-75M” (DIC Corporation), cresol novolak type Epoxy resin trade name “EPICLON-N660” (DIC), phenol novolat Type epoxy resin product name “jER-152” (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resin product name “NC3000” (manufactured by Nippon Kayaku Co., Ltd.), “NC3000H” (manufactured by Nippon Kayaku Co., Ltd.), “NC3000L (Manufactured by Nippon Kayaku Co., Ltd.), trade name of naphthalene type epoxy resin “ESN-175S” (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) and the like.

(B) Among the above epoxy resins, an epoxy resin having a silsesquioxane skeleton can be more suitably used as the thermosetting component. By blending an epoxy resin having a silsesquioxane skeleton, the proportion of the inorganic component of the composition increases and the viscosity component decreases. As a result, the maximum value of Tan δ is reduced, and the cured product is difficult to cure and shrink at high temperatures. The epoxy resin having a silsesquioxane skeleton is a silsesquioxane, that is, a network polymer or polyhedral cluster having a structure of (RSiO _1.5 ) _n obtained by hydrolyzing a trifunctional silane. Any compound having an epoxy group-containing group is not particularly limited. Each silicon of silsesquioxane is bonded with an average of 1.5 oxygen atoms and one hydrocarbon group.

The epoxy resin having a silsesquioxane skeleton preferably has a silsesquioxane skeleton represented by the following general formula (1).

(Wherein R ¹ to R ⁴ are each independently a group having a SiO bond or an organic group, and at least one of R ¹ to R ⁴ is a group having an epoxy group) A group refers to a group containing a carbon atom.

The structure of the silsesquioxane is not particularly limited, and a silsesquioxane having a known and conventional structure such as a random structure, a ladder structure, a complete cage structure, or an incomplete cage structure can be used.

The group having an SiO bond that R ¹ to R ⁴ can take is not particularly limited, a group having an SiO bond and an aliphatic skeleton, a group having an SiO bond and an aromatic skeleton, a group having an SiO bond and a hetero atom, and the like And is preferably within the range of the equivalent of the above thermosetting functional group (epoxy group).

The organic group containing a carbon atom that can be taken by R ¹ to R ⁴ is not particularly limited, and examples thereof include an aliphatic group such as a methyl group, an aromatic group such as a phenyl group, and a group having a hetero atom. The organic group is preferably an organic group having 1 to 30 carbon atoms, and is preferably within an equivalent range of the thermosetting functional group (epoxy group).

At least one of R ¹ to R ⁴ is a group having an epoxy group, and the group having an epoxy group is not particularly limited as long as the group having SiO bond or the organic group has an epoxy group. .

(B) The blending amount of the thermosetting component is, for example, 1 to 100 parts by weight, preferably 10 to 80 parts by weight, and more preferably 20 to 60 parts by weight with respect to 100 parts by weight of the (A) alkali-soluble resin. (B) Crack resistance and insulation reliability will improve that the compounding quantity of a thermosetting component is 1 mass part or more, and storage stability will improve that it is 100 mass parts or less.

The curable resin composition of the present invention has an epoxy equivalent of 300 g / eq. Within the range not impairing the effects of the present invention. You may contain well-known thermosetting components other than the following epoxy resins. For example, amino resins such as melamine resin, benzoguanamine resin, melamine derivative, benzoguanamine derivative, isocyanate compound, block isocyanate compound, cyclocarbonate compound, epoxy equivalent is 300 g / eq. Known compounds such as epoxy resins, oxetane compounds, episulfide resins, bismaleimides, carbodiimide resins, and the like can be used. Particularly preferred are compounds having a plurality of cyclic ether groups or cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in the molecule. The compound having a plurality of cyclic (thio) ether groups in the molecule is a compound having a plurality of 3, 4 or 5-membered cyclic (thio) ether groups in the molecule. A compound having a group, that is, a polyfunctional epoxy compound, a compound having a plurality of oxetanyl groups in the molecule, that is, a polyfunctional oxetane compound, a compound having a plurality of thioether groups in the molecule, that is, a polyfunctional episulfide resin.

[(C) Compound having ethylenically unsaturated group]
The curable resin composition of the present invention contains (C) a compound having an ethylenically unsaturated group. (C) As a compound having an ethylenically unsaturated group, a compound having one or more ethylenically unsaturated groups in the molecule is preferably used. As the compound having an ethylenically unsaturated group, a photopolymerizable oligomer, a photopolymerizable vinyl monomer, or the like, which is a conventionally known compound having an ethylenically unsaturated group, can be used. The compound (C) having an ethylenically unsaturated group mentioned here does not include (A) an alkali-soluble resin having an ethylenically unsaturated group and (E) a surface-treated inorganic filler. .

Examples of the photopolymerizable oligomer include unsaturated polyester oligomers and (meth) acrylate oligomers. Examples of (meth) acrylate oligomers include phenol novolac epoxy (meth) acrylate, cresol novolac epoxy (meth) acrylate, epoxy (meth) acrylates such as bisphenol type epoxy (meth) acrylate, urethane (meth) acrylate, epoxy urethane (meta ) Acrylate, polyester (meth) acrylate, polyether (meth) acrylate, polybutadiene-modified (meth) acrylate, and the like.

As the photopolymerizable vinyl monomer, known and commonly used monomers, for example, styrene derivatives such as styrene, chlorostyrene and α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate or vinyl benzoate; vinyl isobutyl ether, vinyl- vinyl ethers such as n-butyl ether, vinyl-t-butyl ether, vinyl-n-amyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinyl cyclohexyl ether, ethylene glycol monobutyl vinyl ether, triethylene glycol monomethyl vinyl ether; acrylamide, Methacrylamide, N-hydroxymethylacrylamide, N-hydroxymethylmethacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide (Meth) acrylamides such as rilamide and N-butoxymethylacrylamide; allyl compounds such as triallyl isocyanurate, diallyl phthalate and diallyl isophthalate; 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tetrahydrofurfuryl Esters of (meth) acrylic acid such as (meth) acrylate, isobornyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate; hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, pentaerythritol Hydroxyalkyl (meth) acrylates such as tri (meth) acrylate; Alkyl such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate Coxyalkylene glycol mono (meth) acrylates; ethylene glycol di (meth) acrylate, butanediol di (meth) acrylates, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tri Alkylene polyol poly (meth) acrylates such as methylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate; diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, Polyoxyalkylene glycol poly (such as ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane tri (meth) acrylate) Poly (meth) acrylates such as hydroxypivalic acid neopentyl glycol ester di (meth) acrylate; isocyanurate-type poly (meth) acrylates such as tris [(meth) acryloxyethyl] isocyanurate Can be mentioned. These can be used alone or in combination of two or more according to the required properties.

The compounding amount of the compound (C) having an ethylenically unsaturated group is preferably less than 20 parts by mass, more preferably 5 to 18 parts by mass with respect to 100 parts by mass of the (A) alkali-soluble resin. More preferably, it is 10 to 15 parts by mass. (C) By reducing the compounding quantity of the compound which has an ethylenically unsaturated group, the compound which has an unreacted ethylenically unsaturated group in hardened | cured material is reduced, and a loss elastic modulus (viscous component) is reduced. Can do.

[(D) Photopolymerization initiator]
(D) Any photopolymerization initiator may be used as long as it is a known photopolymerization initiator as a photopolymerization initiator or a photoradical generator.

Examples of the photopolymerization initiator include bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2, 6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine oxide, bis- ( 2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6- Trimethylbenzoyl) -phenylphosphine oxide Bisacylphosphine oxides such as (IRSFACURE 819 manufactured by BASF Japan); 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphinic acid Monoacylphosphine oxides such as methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (IRGACURE TPO manufactured by BASF Japan Ltd.) 1-hydroxy-cyclohexyl phenyl ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1 Propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one, 2-hydroxy-2 -Hydroxyacetophenones such as methyl-1-phenylpropan-1-one; benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether; benzoin alkyl Ethers; benzophenones such as benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone; acetophenone, 2,2-dimeth Xyl-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino -1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl) -1- [ Acetophenones such as 4- (4-morpholinyl) phenyl] -1-butanone and N, N-dimethylaminoacetophenone; thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethyl Thioxanthone, 2-chlorothioxanthone, 2,4 Thioxanthones such as diisopropylthioxanthone; anthraquinones such as anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone; acetophenone Ketals such as dimethyl ketal and benzyl dimethyl ketal; benzoates such as ethyl-4-dimethylaminobenzoate, 2- (dimethylamino) ethyl benzoate and p-dimethylbenzoic acid ethyl ester; 1,2-octanedione, 1 -[4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]- Oxime esters such as 1- (O-acetyloxime); bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) phenyl ) Titanocenes such as titanium, bis (cyclopentadienyl) -bis [2,6-difluoro-3- (2- (1-pyr-1-yl) ethyl) phenyl] titanium; phenyl disulfide 2-nitrofluorene, Examples include butyroin, anisoin ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide, and the like. A photoinitiator may be used individually by 1 type and may be used in combination of 2 or more type. Of these, monoacylphosphine oxides and oxime esters are preferable, and oxime esters having high sensitivity are most preferable. The oxime esters preferably have one or more oxime ester groups. For example, ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]- , 1- (O-acetyloxime) is more preferred.

The blending amount of the photopolymerization initiator is preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the (A) alkali-soluble resin. When the amount is 0.5 parts by mass or more, the surface curability is good, and when the amount is 20 parts by mass or less, halation hardly occurs and good resolution is obtained.

[(E) Surface-treated inorganic filler]
The curable resin composition of the present invention has an average particle size of 100 nm to 1 μm and (A) an alkali-soluble resin, (B) a thermosetting component, and (C) at least one compound having an ethylenically unsaturated group, Contains (E) a surface-treated inorganic filler having a reactive group capable of reacting.

The inorganic filler is not particularly limited, and known and commonly used fillers such as silica, crystalline silica, Neuburg silica, aluminum hydroxide, glass powder, talc, clay, magnesium carbonate, calcium carbonate, natural mica, synthetic mica Inorganic fillers such as aluminum hydroxide, barium sulfate, barium titanate, iron oxide, non-fibrous glass, hydrotalcite, mineral wool, aluminum silicate, calcium silicate and zinc white can be used. Among these, silica is preferable, and since the surface area is small and stress is dispersed throughout, it is difficult to become a starting point of cracks, and from the viewpoint of excellent resolution, spherical silica is more preferable.

Examples of the reactive group of the (E) surface-treated inorganic filler include (meth) acryloyl group, vinyl group, cyclic (thio) ether group, acidic group, and basic group.
Examples of the cyclic (thio) ether group include an epoxy group, an oxetanyl group, and an episulfide group.
Examples of the acidic group include a carboxyl group, a phenolic hydroxyl group, an alcoholic hydroxyl group, a thiol group, a sulfone group, and a phosphate group.
Examples of the basic group include an amino group, an amide group, and an ammonium group.
(E) The reactive group of the surface-treated inorganic filler is preferably any one of a (meth) acryloyl group, a vinyl group, and a cyclic (thio) ether group. (E) When the reactive group of the surface-treated inorganic filler is a cyclic (thio) ether group, it is excellent in (A) reactivity with an alkali-soluble resin, and is a (meth) acryloyl group or vinyl group (A) ) Excellent reactivity with the ethylenically unsaturated group of the alkali-soluble resin.

The method for introducing the reactive group into the inorganic filler is not particularly limited, and may be introduced using a known and commonly used method. The surface treatment agent having the reactive group, for example, the coupling having the reactive group. The surface of the inorganic filler may be treated with an agent or the like.

As the surface treatment of the inorganic filler, a surface treatment with a coupling agent is preferable. As the coupling agent, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, or the like can be used. Among these, a silane coupling agent is preferable.

Examples of the silane coupling agent capable of introducing the reactive group into the inorganic filler include a silane coupling agent having a vinyl group, a silane coupling agent having a methacryl group, a silane coupling agent having an acrylic group, and an epoxy group. Examples of the silane coupling agent include a silane coupling agent and a carboxyl group-containing silane coupling agent, and among them, a silane coupling agent having at least one of a (meth) acryl group and a vinyl group is preferable.

(E) The surface-treated inorganic filler should just be mix | blended with the curable resin composition of this invention in the surface-treated state, and mix | blends the surface untreated inorganic filler and surface treatment agent separately. Then, although the inorganic filler may be surface-treated in the composition, it is preferable to blend an inorganic filler that has been surface-treated in advance. By blending the inorganic filler that has been surface-treated in advance, it is possible to prevent a decrease in crack resistance or the like due to the surface-treating agent that has not been consumed by the surface treatment that may remain when blended separately. When the surface treatment is performed in advance, it is preferable to blend a pre-dispersion liquid in which an inorganic filler is pre-dispersed in a solvent or a resin component. It is more preferable that the pre-dispersed liquid is blended in the composition after blending or sufficiently surface-treating when the surface-untreated inorganic filler is pre-dispersed in the solvent.

(E) The average particle size of the surface-treated inorganic filler is preferably 100 to 800 nm, more preferably 100 to 700 nm, and even more preferably 200 to 700 nm. In this specification, (E) the average particle diameter of the surface-treated inorganic filler is not only the particle diameter of the primary particles but also the average particle diameter including the particle diameter of the secondary particles (aggregates) (D50 ). The average particle size can be determined by a laser diffraction particle size distribution measuring device. Examples of the measuring apparatus using the laser diffraction method include Nanotrac wave manufactured by Nikkiso Co., Ltd.

(E) Since the storage elastic modulus increases as the blending amount of the surface-treated inorganic filler increases, Tan δ decreases, and the cured product becomes difficult to expand. (E) Blending of the surface-treated inorganic filler The amount is preferably 35% by mass or more based on the total solid content of the curable resin composition. More preferably, it is 38 to 80% by mass.

(Thermosetting catalyst)
The curable resin composition of the present invention preferably contains a thermosetting catalyst. Examples of such thermosetting catalysts include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. Imidazole derivatives such as 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N -Amine compounds such as dimethylbenzylamine and 4-methyl-N, N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino S-triazine derivatives such as -S-triazine / isocyanuric acid adducts and 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid adducts can also be used. A compound that also functions in combination with a thermosetting catalyst.

The blending amount of the thermosetting catalyst is preferably 0.05 to 20 parts by mass, more preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the (B) thermosetting component.

(Curing agent)
The curable resin composition of the present invention can contain a curing agent. Examples of the curing agent include phenol resins, polycarboxylic acids and acid anhydrides thereof, cyanate ester resins, active ester resins, maleimide compounds, and alicyclic olefin polymers. A hardening | curing agent can be used individually by 1 type or in combination of 2 or more types.

(Coloring agent)
The curable resin composition of the present invention may contain a colorant. As the colorant, known colorants such as red, blue, green, yellow, black, and white can be used, and any of pigments, dyes, and pigments may be used. However, it is preferable not to contain a halogen from the viewpoint of reducing the environmental burden and affecting the human body.

The addition amount of the colorant is not particularly limited, but is preferably 10 parts by mass or less, particularly preferably 0.1 to 7 parts by mass with respect to 100 parts by mass of the (A) alkali-soluble resin.

(Organic solvent)
The curable resin composition of the present invention can contain an organic solvent for the purpose of preparing the composition and adjusting the viscosity when applied to a substrate or a carrier film. Examples of organic solvents include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether , Glycol ethers such as dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, tripropylene glycol monomethyl ether; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butylcarby Tall acetate, propylene glycol monomethyl ether acetate, dip Propylene glycol monomethyl ether acetate, esters such as propylene carbonate; octane, aliphatic hydrocarbons decane; petroleum ether, petroleum naphtha, and petroleum solvents such as solvent naphtha, organic solvents conventionally known can be used. These organic solvents can be used alone or in combination of two or more.

(Other optional ingredients)
Furthermore, you may mix | blend the other well-known and usual additive in the field | area of an electronic material with the curable resin composition of this invention. Other additives include thermal polymerization inhibitors, UV absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial / antifungal agents, antifoaming agents, leveling agents, thickening agents Agent, adhesion imparting agent, thixotropic agent, photoinitiator aid, sensitizer, thermoplastic resin, organic filler, mold release agent, surface treatment agent, dispersant, dispersion aid, surface modifier, stabilizer , Phosphor, AB type or ABA type block copolymer, and the like.

The curable resin composition of the present invention may be used as a dry film or as a liquid. When used as a liquid, it may be one-component or two-component or more.

Next, the dry film of the present invention has a resin layer obtained by applying and drying the curable resin composition of the present invention on a carrier film. When forming a dry film, first, the curable resin composition of the present invention is diluted with the above organic solvent to adjust to an appropriate viscosity, and then a comma coater, a blade coater, a lip coater, a rod coater, and a squeeze coater. Apply a uniform thickness on the carrier film using a reverse coater, transfer roll coater, gravure coater, spray coater or the like. Thereafter, the applied composition is usually dried at a temperature of 40 to 130 ° C. for 1 to 30 minutes to form a resin layer. The coating film thickness is not particularly limited, but in general, the film thickness after drying is appropriately selected in the range of 3 to 150 μm, preferably 5 to 60 μm.

As the carrier film, a plastic film is used. For example, a polyester film such as polyethylene terephthalate (PET), a polyimide film, a polyamideimide film, a polypropylene film, a polystyrene film, or the like can be used. The thickness of the carrier film is not particularly limited, but is generally appropriately selected within the range of 10 to 150 μm. More preferably, it is in the range of 15 to 130 μm.

After the resin layer made of the curable resin composition of the present invention is formed on the carrier film, a cover that can be peeled off on the surface of the resin layer for the purpose of preventing dust from adhering to the surface of the resin layer. It is preferable to laminate films. As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, or the like can be used. As a cover film, what is necessary is just a thing smaller than the adhesive force of a resin layer and a carrier film when peeling a cover film.

In the present invention, the resin layer may be formed by applying and drying the curable resin composition of the present invention on the cover film, and a carrier film may be laminated on the surface. That is, as the film to which the curable resin composition of the present invention is applied when producing a dry film in the present invention, either a carrier film or a cover film may be used.

The printed wiring board of the present invention has a curable resin composition of the present invention or a cured product obtained from a resin layer of a dry film. As a method for producing a printed wiring board of the present invention, for example, the curable resin composition of the present invention is adjusted to a viscosity suitable for a coating method using the organic solvent, and a dip coating method is performed on a substrate. After applying by a flow coating method, roll coating method, bar coater method, screen printing method, curtain coating method or the like, the organic solvent contained in the composition is volatilized and dried (temporary drying) at a temperature of 60 to 100 ° C. Thus, a tack-free resin layer is formed. Moreover, in the case of a dry film, after bonding together on a base material so that a resin layer may contact a base material with a laminator etc., a resin layer is formed on a base material by peeling a carrier film.

Examples of the base material include printed wiring boards and flexible printed wiring boards that have been previously formed with copper or the like, paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth / non-woven cloth epoxy, glass cloth / paper epoxy. Using copper-clad laminates for high-frequency circuits using synthetic fiber epoxy, fluororesin, polyethylene, polyphenylene ether, polyphenylene oxide, cyanate, etc., and copper-clad laminates of all grades (FR-4, etc.) Examples thereof include a plate, a metal substrate, a polyimide film, a PET film, a polyethylene naphthalate (PEN) film, a glass substrate, a ceramic substrate, and a wafer plate.

Volatile drying performed after the application of the curable resin composition of the present invention is performed in a dryer using a hot air circulation drying furnace, an IR furnace, a hot plate, a convection oven or the like (equipped with a heat source of an air heating method using steam). The method can be carried out using a method in which hot air is brought into countercurrent contact and a method in which the hot air is blown onto the support.

After forming a resin layer on the printed wiring board, it is selectively exposed with active energy rays through a photomask having a predetermined pattern, and the unexposed portion is diluted with a dilute alkaline aqueous solution (for example, 0.3 to 3 mass% sodium carbonate aqueous solution). ) To form a cured product pattern. Further, the cured product is irradiated with active energy rays and then heat-cured (for example, 100 to 220 ° C.), irradiated with active energy rays after heat-curing, or is subjected to final finish curing (main curing) only by heat-curing. A cured film having excellent properties such as properties and hardness is formed.

The exposure apparatus used for the active energy ray irradiation may be any apparatus that irradiates ultraviolet rays in the range of 350 to 450 nm, equipped with a high-pressure mercury lamp lamp, an ultra-high pressure mercury lamp lamp, a metal halide lamp, a mercury short arc lamp, etc. Furthermore, a direct drawing apparatus (for example, a laser direct imaging apparatus that directly draws an image with a laser using CAD data from a computer) can also be used. The lamp light source or laser light source of the direct drawing machine may have a maximum wavelength in the range of 350 to 450 nm. The exposure amount for image formation varies depending on the film thickness and the like, but can be generally in the range of 10 to 1000 mJ / cm ² , preferably 20 to 800 mJ / cm ² .

The developing method can be a dipping method, a shower method, a spray method, a brush method, etc., and as a developing solution, potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, Alkaline aqueous solutions such as ammonia and amines can be used.

The curable resin composition of the present invention is preferably used for forming a cured film on a printed wiring board, more preferably used for forming a permanent film, and more preferably a solder resist, Used to form interlayer insulation layers and coverlays. Further, it is suitable for forming a printed wiring board having a fine pitch wiring pattern which requires a high degree of reliability, such as a package substrate, particularly a permanent film (particularly a solder resist) for FC-BGA. In particular, according to the curable resin composition of the present invention, a cured product having excellent crack resistance when a high temperature load is applied can be obtained, which is suitable for applications exposed to high temperature conditions such as in-vehicle applications.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. In the following description, “parts” and “%” are all based on mass unless otherwise specified.

[Synthesis of Alkali-soluble Resin A-1]
119.4 parts of a novolac-type cresol resin (trade name “Shonol CRG951”, manufactured by Showa Polymer Co., Ltd., OH equivalent: 119.4) in an autoclave equipped with a thermometer, a nitrogen introduction device / alkylene oxide introduction device, and a stirring device. Then, 1.19 parts of potassium hydroxide and 119.4 parts of toluene were introduced, the inside of the system was replaced with nitrogen while stirring, and the temperature was increased by heating. Next, 63.8 parts of propylene oxide was gradually added dropwise and reacted at 125 to 132 ° C. and 0 to 4.8 kg / cm ² for 16 hours. Thereafter, the reaction solution was cooled to room temperature, and 1.56 parts of 89% phosphoric acid was added to and mixed with the reaction solution to neutralize potassium hydroxide. The nonvolatile content was 62.1%, and the hydroxyl value was 182.2 mgKOH / g (307. 9 g / eq.) Of a novolak-type cresol resin propylene oxide reaction solution. This was an average of 1.08 mol of propylene oxide added per equivalent of phenolic hydroxyl group.
293.0 parts of a propylene oxide reaction solution of the obtained novolac-type cresol resin, 43.2 parts of acrylic acid, 11.53 parts of methanesulfonic acid, 0.18 part of methylhydroquinone and 252.9 parts of toluene were mixed with a stirrer and a temperature. It was introduced into a reactor equipped with a meter and an air blowing tube, and air was blown at a rate of 10 ml / min and reacted at 110 ° C. for 12 hours while stirring. 12.6 parts of water was distilled from the water produced by the reaction as an azeotrope with toluene. Thereafter, the reaction solution was cooled to room temperature, neutralized with 35.35 parts of a 15% aqueous sodium hydroxide solution, and then washed with water. Thereafter, toluene was distilled off while substituting 118.1 parts of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolak acrylate resin solution. Next, 332.5 parts of the obtained novolak acrylate resin solution and 1.22 parts of triphenylphosphine were introduced into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and air was supplied at a rate of 10 ml / min. With stirring, 60.8 parts of tetrahydrophthalic anhydride was gradually added, reacted at 95 to 101 ° C. for 6 hours, cooled and taken out. In this way, a solution of a carboxyl group-containing photosensitive resin A-1 having a nonvolatile content of 65% and a solid acid value of 87.7 mgKOH / g was obtained.

[Synthesis of alkali-soluble resin A-2]
700 g of diethylene glycol monoethyl ether acetate and 1070 g of orthocresol novolac type epoxy resin (manufactured by DIC, EPICLON N-695, softening point 95 ° C., epoxy equivalent 214, average reactive group number 7.6): number of glycidyl groups (total number of aromatic rings): 5.0 mol), 360 g (5.0 mol) of acrylic acid, and 1.5 g of hydroquinone were charged, heated and stirred at 100 ° C., and uniformly dissolved.
Next, 4.3 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours, and further 1.6 g of triphenylphosphine was added, and the temperature was raised to 120 ° C. and reacted for another 12 hours. To the obtained reaction solution, 562 g of aromatic hydrocarbon (Sorvesso 150) and 684 g (4.5 mol) of tetrahydrophthalic anhydride were charged and reacted at 110 ° C. for 4 hours. Furthermore, 142.0 g (1.0 mol) of glycidyl methacrylate was added to the obtained reaction liquid, and the reaction was performed at 115 ° C. for 4 hours to obtain a carboxyl group-containing photosensitive resin solution (A-2).
The photosensitive resin solution (A-2) thus obtained had a solid content of 65% and an acid value of the solid content of 87 mgKOH / g.

[Synthesis of epoxy resin having silsesquioxane skeleton B-1]
90.0 parts of γ-glycidoxypropyltrimethoxysilane, 3.0 parts of phenyltrimethoxysilane, 2.0 parts of methyltrimethoxysilane, and 93 parts of methyl isobutyl ketone were charged into a reaction vessel, and the temperature was raised to 80 ° C. After the temperature increase, 21.6 parts of a 0.1 wt% aqueous potassium hydroxide solution was continuously added dropwise over 30 minutes. After completion of the dropping, the reaction was carried out at 80 ° C. for 5 hours while removing the produced methanol. After completion of the reaction, washing with water was repeated until the washing solution became neutral. Next, 69 parts of an epoxy resin having a silsesquioxane skeleton was obtained by removing the solvent under reduced pressure. The epoxy equivalent of the obtained epoxy resin is 176 g / eq. The weight average molecular weight was 2200.

[Preparation of surface-treated inorganic filler (silica) E-1]
70 g of spherical silica (SFP-30M manufactured by Denka Co., Ltd., average particle diameter: 600 nm), 28 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and a silane coupling agent having a methacryl group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) 2 g was uniformly dispersed to obtain a silica solvent dispersion E-1.

[Preparation of surface-treated inorganic filler (silica) E-2]
70 g of spherical silica (SFP-20M manufactured by Denka Co., Ltd., average particle size: 300 nm), 28 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and a silane coupling agent having an epoxy group (KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd.) 4 g was uniformly dispersed to obtain a silica solvent dispersion E-2.

[Examples 1 to 17, Comparative Examples 1 to 5]
The above resin solution (varnish) was blended together with various components shown in Tables 1 to 3 in proportions (parts by mass) shown in Tables 1 to 3, premixed with a stirrer, and then kneaded with a three-roll mill, A curable resin composition was prepared.

<Production of dry film>
The curable resin composition obtained as described above was diluted by adding 300 g of methyl ethyl ketone, and stirred for 15 minutes with a stirrer to obtain a coating solution. The coating solution is applied onto a 38 μm thick polyethylene terephthalate film (Embret PTH-25 manufactured by Unitika Co., Ltd.) having an arithmetic surface roughness Ra of 150 nm, usually dried at a temperature of 80 ° C. for 15 minutes, and a photosensitive material having a thickness of 20 μm. A functional resin layer was formed. Next, a 18 μm-thick polypropylene film (OPP-FOA manufactured by Futamura Co., Ltd.) was bonded onto the photosensitive resin layer to produce a photosensitive dry film.

<Preparation of cured coating film>
On the low profile copper foil, the polyethylene film is peeled from the photosensitive dry film obtained as described above, and the photosensitive resin layer of the photosensitive dry film is bonded to the copper foil surface side. Using a vacuum laminator (MVLP-500 manufactured by Meiki Seisakusho Co., Ltd.), the substrate and the photosensitive resin layer were laminated by heating and laminating under conditions of pressure: 0.8 MPa, 70 ° C., 1 minute, and vacuum: 133.3 Pa. Adhered.
Next, using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp), the photosensitive dry film is exposed (exposure amount: 400 to 600 mJ / cm ² ), and then the polyethylene terephthalate film is peeled off from the photosensitive dry film. The photosensitive resin layer was exposed. Thereafter, development was performed for 60 seconds under conditions of 30 ° C. and a spray pressure of 2 kg / cm ² using a 1 wt% Na ₂ CO ₃ aqueous solution to form a resin layer having a predetermined resist pattern. Subsequently, the resin layer was irradiated with an exposure amount of 1 J / cm ^{2 in} a UV conveyor furnace equipped with a high-pressure mercury lamp, and then heated at 160 ° C. for 60 minutes to completely cure the resin layer to prepare a cured coating film.

<Evaluation of Tan δ, Tg, storage elastic modulus>
The cured coating film obtained as described above was peeled off from the copper foil, and a sample was cut out to obtain a measurement size (5 mm × 10 mm size), and the temperature was increased from 25 ° C. to 300 ° C. with DMS6100 manufactured by Hitachi High-Tech. Measurement was performed at a temperature of 5 ° C./minute, a frequency of 1 Hz, and a tensile sine wave mode.
Tan δ took the maximum value in the temperature measurement region, the temperature at that time was Tg, and the storage elastic modulus (E ′) was 25 ° C. (E′1) and 150 ° C. (E′2).
The change rate of the storage elastic modulus (E ′) was obtained by calculating from (E′1−E′2) / E′1 using the storage elastic modulus at the two points.

<Evaluation of CTE>
The cured coating film obtained as described above was peeled off from the copper foil, a sample was cut out to obtain a measurement size (3 mm × 10 mm size), and CTE was measured with TMA6100 manufactured by Hitachi High-Tech. The measurement conditions were a test load of 5 g, and heating the sample from room temperature at a rate of 10 ° C./min was repeated twice to obtain a linear expansion coefficient (CTE (α2)) of Tg or more in the second time.

<Crack resistance (TCT resistance)>
The surface of a circuit board (50 mm × 50 mm × 0.4 mmt) with a 250 μm bump pitch to be connected to C4 is chemically polished, the polyethylene film is peeled off from the photosensitive dry film obtained as described above, and the surface is polished. Next, the photosensitive resin layer of the photosensitive dry film was bonded to the surface on the other side, and subsequently, using a vacuum laminator (MVLP-500, manufactured by Meiki Seisakusho), the degree of pressure was 0.8 MPa, 70 ° C., 1 minute, Vacuum lamination was performed under the condition of 133.3 Pa, and the substrate and the photosensitive resin layer were brought into close contact with each other. Next, using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp), after exposing from the photosensitive dry film through an exposure mask having a negative pattern having a diameter of 70 μm, a polyethylene terephthalate film is formed from the photosensitive dry film. It peeled and the photosensitive resin layer was exposed. Thereafter, development was performed for 60 seconds under conditions of 30 ° C. and a spray pressure of 2 kg / cm ² using a 1 wt% Na ₂ CO ₃ aqueous solution to form a resin layer having a predetermined resist pattern. Subsequently, the resin layer was irradiated with an exposure amount of 1 J / cm ^{2 in} a UV conveyor furnace equipped with a high-pressure mercury lamp, and then heated at 160 ° C. for 60 minutes to completely cure the resin layer to form a cured film. A TST evaluation substrate provided with a cured coating thereon was produced.
Next, after mounting a 20 mm square chip by the C4 method, heat treatment was performed at 125 ° C. for 24 hours as preconditioning, and humidification treatment was performed at 60 ° C. and humidity 60% for 48 hours, and reflow 260 ° C. was performed three times. The obtained substrate was put into a thermal cycle machine in which a temperature cycle between −65 ° C. and 175 ° C. was performed, and TCT (Thermal Cycle Test) was performed. The appearance at 300 cycles, 600 cycles and 800 cycles was observed.
A: No abnormality after 1000 cycles.
A: No abnormality after 800 cycles.
○: Cracks occurred at 800 cycles.
Δ: Cracks occurred at 600 cycles.
X: Cracks occurred in 300 cycles.

* 1: Carboxyl group-containing resin A-1 synthesized above (alkali-soluble group equivalent: 701.3 g / eq.)
* 2: Carboxyl group-containing resin A-2 synthesized above (alkali-soluble group equivalent: 579 g / eq.)
* 3: PCR-1170H (carboxyl group-containing resin starting from phenol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd. (alkali-soluble group equivalent: 656 g / eq.)
* 4: Epoxy resin B-1 having a silsesquioxane skeleton synthesized above (epoxy equivalent: 176 g / eq., Bifunctional, softening point: −50 ° C.)
* 5: Epicron N-740 manufactured by DIC (phenol novolac type epoxy resin, epoxy equivalent: 180 g / eq., Trifunctional, softening point: 30 ° C.)
* 6: Epicron HP-7200H manufactured by DIC (epoxy resin having a dicyclopentadiene skeleton, epoxy equivalent: 280 g / eq., Bifunctional, softening point: 75 to 90 ° C.)
* 7: Epicron HP-820 manufactured by DIC (alkylphenol type epoxy resin, epoxy equivalent: 225 g / eq., Bifunctional, liquid)
* 8: Epototo YDC-1312 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. (hydroquinone type epoxy resin, epoxy equivalent: 178 g / eq., Bifunctional, softening point: 140 ° C.)
* 9: Epototo YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. (bisphenol F type epoxy resin, epoxy equivalent: 195 g / eq., Bifunctional, softening point: 80 ° C.)
* 10: Epicron 152 (Tetrabromobisphenol A type epoxy resin, epoxy equivalent: 360 g / eq., Bifunctional, softening point: 56 to 66 ° C.) manufactured by DIC
* 11: jER1001 manufactured by Mitsubishi Chemical Corporation (bisphenol A type epoxy resin, epoxy equivalent: 475 g / eq., Bifunctional, softening point: 64 ° C.)
* 12: Shikoku Chemicals 2PHZ (2-phenyl-4,5-dihydroxymethylimidazole)
* 13: Dicyandiamide * 14: DPHA (dipentaerythritol hexaacrylate) manufactured by Nippon Kayaku Co., Ltd.
* 15: Irgacure TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide) manufactured by BASF Japan
* 16: Irgacure OXE02 manufactured by BASF Japan Ltd. (Ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (o-acetyloxime)
* 17: Surface-treated silica solvent dispersion E-1 prepared above (silica having a methacryl group as a reactive group) (silica content 70% by mass (solid content)) (average particle size 600 nm) (in the table) The numerical value indicates the solid content)
* 18: Surface-treated silica solvent dispersion E-2 prepared above (silica having an epoxy group as a reactive group) (silica content 68.6% by mass (solid content)) (average particle size 300 nm) ( (The numbers in the table indicate the solid content)
* 19: Admanex YAMANO YA050C-SV2 (silica having a vinyl group as a reactive group) (average particle size 50 nm)
* 20: Admafine SO-C2 manufactured by Admatechs (spherical silica, average particle size 0.5 μm)
* 21: Admafine SO-C5 manufactured by Admatechs (spherical silica, average particle size 1.5 μm)
* 22: Nippon Kayaku Co., Ltd. NC-3000L (biphenylene type epoxy resin, epoxy equivalent: 273 g / eq., Bifunctional, softening point: 52 ° C.)
* 23: EXA-7241 manufactured by DIC (triphenylmethane type epoxy resin, epoxy equivalent: 168 g / eq., Trifunctional, softening point: 70 ° C.)
* 24: EPICLON-N660 manufactured by DIC (cresol novolac type epoxy resin, epoxy equivalent: 210 g / eq., Bifunctional, softening point: 61 to 69 ° C.)

From the results shown in the above table, it can be seen that the cured products of the curable resin compositions of Examples 1 to 17 of the present invention are excellent in crack resistance. In contrast, in the cured products of the curable resin compositions of Comparative Examples 1 to 5, the maximum value of Tan δ exceeded 0.15, and crack resistance could not be obtained.

Claims

(A) an alkali-soluble resin,
(B) thermosetting component,
(C) a compound having an ethylenically unsaturated group,
(D) a photopolymerization initiator, and
(E) a resin composition containing a surface-treated inorganic filler,
The (E) surface-treated inorganic filler has an average particle diameter of 100 nm to 1 μm, and contains the (A) alkali-soluble resin, the (B) thermosetting component, and the (C) ethylenically unsaturated group. Having a reactive group capable of reacting with at least one of the compounds having
As said (B) thermosetting component, epoxy equivalent 300g / eq. Including the following epoxy resin,
In a cured product having a thickness of 40 μm obtained from the resin composition, the maximum value of Tan δ in a dynamic viscoelasticity measurement from 25 ° C. to 300 ° C. under a condition of a frequency of 1 Hz and a temperature increase rate of 5 ° C./min is 0. A curable resin composition, which is 15 or less.
The epoxy equivalent 300 g / eq. The following epoxy resin includes (B-1) a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower and (B-2) a bifunctional or higher functional epoxy resin having a softening point of 40 ° C. or lower. The curable resin composition according to 1.
2. The curable resin composition according to claim 1, wherein the compounding amount of the compound (C) having an ethylenically unsaturated group is less than 20 parts by mass with respect to 100 parts by mass of the (A) alkali-soluble resin. .
The curable resin composition according to claim 1, wherein the amount of the (E) surface-treated inorganic filler is 35% by mass or more in the solid content of the curable resin composition.
When the dynamic viscoelasticity measurement is performed from 25 ° C. to 300 ° C. under the conditions of a frequency of 1 Hz and a heating rate of 5 ° C./min, the storage elastic modulus at 150 ° C. is 1 GPa or more and 25 ° C. to The curable resin composition according to claim 1, wherein the rate of change in storage modulus up to 150 ° C is within 70%.
The curable resin composition according to claim 1, wherein CTEα2 of the cured product is 110 ppm or less.
The curable resin composition according to claim 1, wherein Tg of the cured product is 160 ° C or higher.
The curable resin composition according to claim 1, which is used for forming a solder resist.
A dry film comprising a resin layer obtained by applying the curable resin composition according to claim 1 to a film and drying the film.
A curable resin composition according to any one of claims 1 to 8, or a cured product obtained by curing the resin layer of the dry film according to claim 9.
A printed wiring board comprising the cured product according to claim 10.