Curable components, their cured forms, prepregs, circuit boards, extension films, semiconductor sealants, and semiconductor devices.

Abstract

This invention provides a curable composition, its cured form, a prepreg, a circuit board, a layering film, a semiconductor sealant, and a semiconductor device. The curable composition, even when formulated with a hydrocarbon resin (hydrocarbon plasticizer) of extremely low polarity, exhibits high compatibility. The cured form of this curable composition has a low dielectric loss tangent. A curable composition is used, comprising an active ester resin, a hydrocarbon resin, and a curing agent. In this curable composition, the active ester resin is a reaction product of a resin (A) having phenolic hydroxyl groups and an aromatic dicarboxylic acid or its acid halide (B). The resin (A) having phenolic hydroxyl groups is a reaction product of an alkyl compound (a1) having 5 or more carbon atoms and a phenolic hydroxyl group and a divinyl compound (a2).

Description

Technical Field

[0001] The present invention relates to a curable composition, a cured product thereof, a prepreg, a circuit board, an interlayer film, a semiconductor encapsulant, and a semiconductor device. Prior Art

[0002] Epoxy resin compositions containing epoxy resins and their curing agents as essential components are widely used in electronic component applications such as semiconductors and multilayer printed circuit boards because their cured products exhibit excellent heat resistance and insulation properties. In the technical field of insulating materials represented by interlayer films in such electronic component applications, in recent years, the high-speed and high-frequency development of signals in various electronic devices has been continuously progressing. With the high-speed and high-frequency development of such signals, there is a demand for a material having a lower dielectric constant and a lower dielectric loss tangent. However, it is difficult to obtain a material that maintains a sufficiently low dielectric constant and has a low dielectric loss tangent.

[0003] Therefore, it has been reported that hydrocarbon plasticizers (for example, refer to Patent Document 1 and Patent Document 2) are used in order to maintain a sufficiently low dielectric constant, dielectric loss tangent, and improve reliability such as dimensional stability for high-speed and high-frequency signals. However, since hydrocarbon plasticizers have extremely low polarity, their compatibility with other resins is extremely low, and it is difficult to prepare a uniform varnish. In addition, laminates, prepregs, and interlayer films using varnishes prepared in a state of low compatibility also have problems such as lack of reliability. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-90954

[0005] [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-135032 Summary of the Invention Problems to be Solved by the Invention

[0006] <U+ The problem to be solved by the present invention is to provide a curable composition, a cured product thereof, a prepreg, a circuit board, an interlayer film, a semiconductor encapsulant, and a semiconductor device, wherein the curable composition has high compatibility even when a hydrocarbon resin (hydrocarbon plasticizer) having extremely low polarity is formulated, and the cured product of the curable composition has a low dielectric loss tangent. Means for Solving the Problems

[0007] The inventors of the present invention made intensive studies to solve the above problems, and as a result, found that a curable composition containing a hydrocarbon resin and a curing agent in a specific active ester has high compatibility, and the cured product thereof has a low dielectric loss tangent, thus completing the present invention.

[0008] That is, the present invention relates to a curable composition containing an active ester resin, a hydrocarbon resin, and a curing agent. In the curable composition, the active ester resin is a reaction product of a resin (A) having a phenolic hydroxyl group and an aromatic dicarboxylic acid or its acid halide (B), and the resin (A) having a phenolic hydroxyl group is a reaction product of a compound (a1) having an alkyl group with 5 or more carbon atoms and a phenolic hydroxyl group and a divinyl compound (a2).

[0009] In addition, the present invention relates to a cured product of the curable composition, a prepreg using the curable composition, a circuit board, an interlayer film, a semiconductor sealing material, and a semiconductor device. Advantages of the Invention

[0010] The curable composition of the present invention has high compatibility even when a hydrocarbon resin with extremely low polarity is formulated, and the cured product thereof has a low dielectric loss tangent. Therefore, it can be used in electronic component applications such as prepregs, circuit boards, interlayer films, and semiconductor sealing materials, and thus can also be used in semiconductor devices using these electronic components. Brief Explanation of Drawings

[0011] FIG. 1 is a GPC chart of the active ester resin (1) obtained in Production Example 1.

[0012] FIG. 2 is a GPC chart of the active ester resin (2) obtained in Production Example 2.

[0013] FIG. 3 is a GPC chart of the active ester resin (1') obtained in Comparative Production Example 1. Embodiments

[0014] The present invention will be described in detail below.

[0015] The active ester resin of the present invention is a reaction product of a resin (A) having a phenolic hydroxyl group and an aromatic dicarboxylic acid or its acid halide (B), and the resin (A) having a phenolic hydroxyl group is a reaction product of a compound (a1) having an alkyl group with 5 or more carbon atoms and a phenolic hydroxyl group and a divinyl compound (a2).

[0016] The compound (a1) is not particularly limited as long as it is an alkyl group having 5 or more carbon atoms and a phenolic hydroxyl group. The alkyl group in the compound (a1) only needs to be an alkyl group having 5 or more carbon atoms, such as pentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, etc. The alkyl group can be straight-chain, branched, or alicyclic. Furthermore, the alkyl group has 5 or more carbon atoms, but preferably 12 or fewer, more preferably 10 or fewer, and most preferably 8 or fewer.

[0017] As the compound (a1), examples of compounds having phenolic hydroxyl groups include phenol and naphthol. Specific examples of the compound (a1) include: pentylphenol, hexylphenol, heptaylphenol, octylphenol, nonylphenol, decylphenol, undecylphenol, dodecylphenol, pentylnaphthol, hexylnaphthol, heptaylnaphthol, octylnaphthol, nonylnaphthol, decylnaphthol, undecylnaphthol, and dodecylnaphthol. Furthermore, the substitution positions of the alkyl and phenolic hydroxyl groups on the aromatic ring of these compounds (a1) are not particularly limited; however, when the compound (a1) is phenol, it is preferable that the alkyl and phenolic hydroxyl groups are substituted at the para position. Additionally, one or more compounds (a1) may be used.

[0018] The divinyl compound (a2) is not particularly limited as long as it is a compound that can react with the compound (a1) to polymerize the compounds (a1) together. Furthermore, one or more divinyl compounds (a2) may be used. Among these, compounds having an aromatic ring or an alicyclic ring in their molecular structure are preferred for forming a compatible and dielectrically excellent active ester resin in the cured product. More preferred examples of the divinyl compound (a2) include compounds represented by the following general formulas (1-1) to (1-4).

[0019] [Chemistry 1]

[0020] [In general formulas (1-1) to (1-4), R1 is independently an aliphatic hydrocarbon group, alkoxy group, halogen atom, aryl group, or aralkyl group, Y is an alkyl group with 1 to 4 carbon atoms, oxygen atom, sulfur atom, or carbonyl group, i is 0 or an integer from 1 to 4, and j is an integer from 1 to 4.]

[0021] In the general formulas (1-1) to (1-4), R1 is independently an aliphatic hydrocarbon group, an alkoxy group, a halogen atom, an aryl group, or an aralkyl group. Specifically, examples include: aliphatic hydrocarbon groups such as methyl, ethyl, vinyl, propyl, butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, and nonyl; alkoxy groups such as methoxy, ethoxy, propoxy, and butoxy; halogen atoms such as fluorine, chlorine, and bromine; phenyl, naphthyl, anthracene, and aryl groups on which the aliphatic hydrocarbon group or alkoxy group or halogen atom is substituted; and phenylmethyl, phenylethyl, naphthylmethyl, naphthylethyl, and aralkyl groups on which the aliphatic hydrocarbon group or alkoxy group or halogen atom is substituted.

[0022] In terms of forming an active ester resin with good compatibility and excellent dielectric properties in the cured product, the compound represented by general formula (1-1) to general formula (1-4) is preferred.

[0023] When the compound represented by the general formulas (1-1) to (1-4) is used as the divinyl compound (a2), the resin (A) having phenolic hydroxyl groups is formed by bonding the compound (a1) to the structural site represented by the following general formula (2).

[0024]

[0025] [In general formula (2), X is represented by any one of the following general formulas (X-1) to (X-4)]

[0026] [Chemistry 3]

[0027] [In general formulas (1-1) to (1-4), R1 is independently an aliphatic hydrocarbon group, alkoxy group, halogen atom, aryl group, or aralkyl group, Y is an alkyl group with 1 to 4 carbon atoms, oxygen atom, sulfur atom, or carbonyl group, i is 0 or an integer from 1 to 4, and j is an integer from 1 to 4.]

[0028] The resin (A) having phenolic hydroxyl groups can also use other compounds besides the compound (a1) and the divinyl compound (a2) as reactants. Examples of other compounds include: various aldehyde compounds, compounds other than the divinyl compound (a2) that can polymerize the compound (a1) (a2'), or substituent introducers (a3) ​​such as aliphatic hydrocarbon groups, alkoxy groups, halogen atoms, aryl groups, or aralkyl groups used to introduce substituents onto the aromatic ring of the resin (A) having phenolic hydroxyl groups.

[0029] When using the compound (a2'), in order to fully utilize the effects of the present invention, which has good compatibility and low dielectric loss tangent in the cured material, the divinyl compound (a2) is preferably 50% by mass or more, and preferably 80% by mass or more, relative to the total of the divinyl compound (a2) and the compound (a2').

[0030] Examples of substituent-introducing agents (a3) ​​include arylalkyl-introducing agents such as phenylmethanol compounds, phenylmethyl halide compounds, naphthylmethanol compounds, naphthylmethyl halide compounds, and styrene compounds.

[0031] The method for manufacturing the resin (A) having phenolic hydroxyl groups is not particularly limited, but it is preferable to adjust the ratio of the reactants so that the number of phenolic hydroxyl groups per molecule is 2 or more. For example, it can be manufactured by using compound (a1) in the range of 2 to 10 mol relative to 1 mol of the divinyl compound (a2), under acid catalyst conditions, and heating and stirring at a temperature of about 80°C to 180°C. The reaction can also be carried out in an organic solvent if necessary. After the reaction is completed, excess compound (a1) can be distilled off if necessary.

[0032] Examples of acid catalysts include p-toluenesulfonic acid, sulfuric acid, hydrochloric acid, oxalic acid, etc., and hydrates of these may also be used. One or more of these catalysts may be used. Furthermore, these acid catalysts may also be used in aqueous solution form. The preferred amount of acid catalyst added is 0.01% to 20% by mass relative to the compound (a1).

[0033] Examples of organic solvents include: ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone; acetate solvents such as ethyl acetate, butyl acetate, cellolytic acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitol solvents such as cellolytic agents and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; dimethylformamide; dimethylacetamide; and N-methylpyrrolidone. One or more of these solvents may be used in combination.

[0034] As a specific example of the resin (A) having phenolic hydroxyl groups, the structure of the resin (a1) using phenol and the divinylbenzene (a2) is illustrated in the following general formula (A-1). Furthermore, the following general formula (A-1) is merely one example of a resin (A) having phenolic hydroxyl groups and does not exclude other resins.

[0035]

[0036] [In general formula (A-1), R1 is an alkyl group with 5 or more carbon atoms, R2 is a hydrogen atom or a structural site represented by the following general formula (R-1), and n is an integer from 1 to 10.]

[0037]

[0038] [In the general formula (R-1), R1 is an alkyl group with 5 or more carbon atoms, and n is an integer from 1 to 10.]

[0039] In addition, commercially available divinylbenzene sometimes contains a portion of ethylstyrene. In this case, as R2 in the general formula (A-1), a portion of the structure represented by the following formula (R-2) is sometimes introduced.

[0040]

[0041] The aromatic dicarboxylic acid or its acid halide (B) is not particularly limited as long as it is an aromatic compound that can react with the phenolic hydroxyl group of the resin (A) having a phenolic hydroxyl group to form an ester bond. Specific examples include: isophthalic acid, terephthalic acid, and other phenyl dicarboxylic acids; trimellitic acid and other phenyl tricarboxylic acids; naphthalene-1,4-dicarboxylic acid, naphthalene-2,3-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, and other naphthalene dicarboxylic acids; their acid halides; and compounds in which the aromatic rings of these are substituted with the aliphatic hydrocarbon group, alkoxy group, halogen atom, etc. Examples of the acid halides include acid chlorides, acid bromides, acid fluorides, and acid iodides. One or more of these may be used. Of particular, for the formation of a highly reactive and excellent curing ester resin, isophthalic acid or terephthalic acid, or other phenyl dicarboxylic acids or their acid halides, are preferred.

[0042] The active ester resin of the present invention can be manufactured, for example, by heating and stirring the resin (A) having phenolic hydroxyl groups and the aromatic dicarboxylic acid or its acid halide (B) at a temperature of about 40°C to 65°C in the presence of an alkaline catalyst. The reaction can also be carried out in an organic solvent if necessary. In addition, after the reaction is completed, the reaction product can be purified by washing with water or reprecipitation if necessary.

[0043] Examples of alkaline catalysts include sodium hydroxide, potassium hydroxide, triethylamine, and pyridine. One or more of these can be used. Alternatively, the alkaline catalyst can be used as an aqueous solution of approximately 3% to 30% by mass. Sodium hydroxide or potassium hydroxide, which have high catalytic activity, are preferred.

[0044] Examples of organic solvents include: ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone; acetate solvents such as ethyl acetate, butyl acetate, cellolytic acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitol solvents such as cellolytic agents and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; dimethylformamide; dimethylacetamide; and N-methylpyrrolidone. One or more of these solvents may be used in combination.

[0045] In addition, the curable composition of the present invention may also contain an ester compound obtained by reacting the compound (a1) remaining in the resin (A) having phenolic hydroxyl groups with the aromatic dicarboxylic acid or its acid halide (B).

[0046] With regard to the lower curing shrinkage rate of the curing composition of the present invention, the weight-average molecular weight (Mw) of the active ester resin is preferably in the range of 600 to 50,000, more preferably in the range of 800 to 30,000. Furthermore, the weight-average molecular weight (Mw) of the active ester resin is a value determined by gel permeation chromatography (GPC).

[0047] Furthermore, the softening point of the active ester resin of the present invention, measured based on Japanese Industrial Standards (JIS) K7234, is preferably in the range of 80°C to 180°C, and more preferably in the range of 85°C to 160°C.

[0048] Regarding the good compatibility and excellent curing properties of the curable composition of the present invention, the functional group equivalent of the active ester resin is preferably in the range of 200 g / equivalent to 350 g / equivalent, and more preferably in the range of 200 g / equivalent to 300 g / equivalent. Furthermore, the functional groups in the active ester resin of the present invention refer to the ester bond sites and phenolic hydroxyl groups in the active ester resin. Additionally, the functional group equivalent of the active ester resin is a value calculated based on the amount of raw material added.

[0049] In addition to the aforementioned active ester resin, the curing composition of this invention also contains a hydrocarbon resin and a curing agent. The hydrocarbon resin is not particularly limited to any resin containing carbon and hydrogen atoms; examples include thermoplastic elastomers. One or more hydrocarbon resins may be used. Examples of the thermoplastic elastomers include: polystyrene-based thermoplastic elastomers such as styrene-butadiene-styrene block copolymers (SBS), styrene-isoprene-styrene block copolymers (SIS), styrene-ethylene-butylene-styrene block copolymers (SEBS), and styrene-ethylene-propylene-styrene block copolymers (SEPS); olefin-based thermoplastic elastomers; and polybutadiene.

[0050] The thermoplastic elastomer is preferably a polystyrene-based thermoplastic elastomer, and more preferably a styrene-ethylene-butene-styrene block copolymer (SEBS). Commercially available SEBS products include: Tuftec manufactured by Asahi Kasei Chemicals Co., Ltd., Rabalon manufactured by Mitsubishi Chemical Co., Ltd., Actymer manufactured by Riken Technos Co., Ltd., Elastomer AR manufactured by Aron Chemical Co., Ltd., Kraton G manufactured by Kraton Polymer Japan Co., Ltd., and the B series and BI series manufactured by Nippon Soda Co., Ltd.

[0051] With regard to good compatibility and lower dielectric loss tangent in the cured product, the proportion of the hydrocarbon resin (excluding organic solvent) in the curing composition of the present invention is preferably in the range of 5% to 40% by mass, and more preferably in the range of 10% to 35% by mass.

[0052] The curing agent is not particularly limited as long as it is a compound that can react with the active ester resin. For example, epoxy resin can be cited as an example of a curing agent.

[0053] Examples of epoxy resins include: phenolic varnish-type epoxy resin, cresol varnish-type epoxy resin, naphthol varnish-type epoxy resin, bisphenol varnish-type epoxy resin, biphenol varnish-type epoxy resin, bisphenol type epoxy resin, biphenyl type epoxy resin, triphenol methane type epoxy resin, tetraphenol ethane type epoxy resin, dicyclopentadiene-phenol addition reaction type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, etc. One or more of these can be used together.

[0054] When using epoxy resin as the curing agent, in addition to the active ester resin, other epoxy resin curing agents may also be used. Examples of other epoxy resin curing agents include: diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylmethane, isophorone diamine, imidazole, BF3-amine complexes, guanidine derivatives, and other amine compounds; dicyandiamine, polyamide resins synthesized from dimers of linoleic acid and ethylenediamine, and other amide compounds; phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, and so on. Anhydrides such as tetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride; phenolic resins such as phenolic varnish resin, cresol phenolic varnish resin, naphthol phenolic varnish resin, bisphenol phenolic varnish resin, biphenyl phenolic varnish resin, dicyclopentadiene-phenol addition-type resin, phenol aralkyl resin, naphthol aralkyl resin, triphenol methane-type resin, tetraphenol ethane-type resin, and aminotriazine-modified phenolic resin. One or more of these can be used together.

[0055] In the case where epoxy resin is used as a curing agent in the curable composition of the present invention, and other epoxy resin curing agents are also used in combination, the preferred ratio of these is 1 mole relative to the total number of epoxy groups in the epoxy resin and the total number of functional groups in the active ester resin and other epoxy resin curing agents is 0.7 to 1.5 moles.

[0056] The curable composition of this invention may also contain, as other resins, cyanate ester resins; bismaleimide resins; benzoxazine resins; styrene-maleic anhydride resins; allyl-containing resins such as diallyl bisphenol and triallyl isocyanurate; polyphosphate esters; phosphate ester-carbonate copolymers, etc. One or more of these may be used.

[0057] The curing composition of the present invention may also contain various additives such as curing accelerators, flame retardants, inorganic fillers, silane coupling agents, release agents, pigments, and emulsifiers, as needed.

[0058] Examples of such curing accelerators include: phosphorus compounds, tertiary amines, imidazole compounds, pyridine compounds, organic acid metal salts, Lewis acids, and amine salts. Among these, in terms of superior curing properties, heat resistance, electrical properties, and moisture resistance, triphenylphosphine is preferred among phosphorus compounds, 1,8-diazabicyclo[5.4.0]undecene (DBU) is preferred among tertiary amines, 2-ethyl-4-methylimidazolium is preferred among imidazole compounds, and 4-dimethylaminopyridine is preferred among pyridine compounds.

[0059] Examples of flame retardants include: red phosphorus, monoammonium phosphate, diammonium phosphate, triammonium phosphate, ammonium polyphosphate, and other inorganic phosphorus compounds such as ammonium phosphate and phosphatidylamine; phosphate ester compounds, phosphonic acid compounds, phosphine oxide compounds, phosphine compounds, organic nitrogen- and phosphorus-containing compounds, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (2,7-Dihydroxynaphthyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and other cyclic organophosphorus compounds and their derivatives obtained by reacting them with compounds such as epoxy resins or phenolic resins; nitrogen-based flame retardants such as triazine compounds, cyanuric acid compounds, isocyanuric acid compounds, and phenanthrene; silicone-based flame retardants such as silicone oil, silicone rubber, and silicone resin; and inorganic flame retardants such as metal hydroxides, metal oxides, metal carbonate compounds, metal powders, boron compounds, and low-melting-point glasses. When using these flame retardants, it is preferable that the content in the curing composition is in the range of 0.1% to 20% by mass.

[0060] The inorganic filler is formulated, for example, when the curable composition of the present invention is used in semiconductor sealing materials. Examples of the inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. Among these, fused silica is preferred for its ability to be formulated in greater quantities. The fused silica can be either crushed or spherical; however, to increase the amount of fused silica and suppress the increase in the melt viscosity of the curable composition, spherical silica is preferred. Furthermore, to increase the amount of spherical silica, the particle size distribution of the spherical silica is preferably adjusted appropriately. The filling rate is preferably formulated in the range of 0.5% to 95% by mass in the curable composition.

[0061] Furthermore, when using the curable composition of the present invention in applications such as conductive pastes, conductive fillers such as silver powder or copper powder can be used.

[0062] As described in detail above, the curable composition of the present invention exhibits excellent properties, including low curing shrinkage and low dielectric loss tangent in the cured product. Furthermore, it demonstrates excellent compatibility even when formulated with hydrocarbon resins of extremely low polarity, thus forming a uniform curable composition and obtaining a uniform cured product. Therefore, even when used in electronic components, it reduces adverse effects on electrical properties. Consequently, the curable composition of the present invention is preferably used in prepregs, circuit boards, semiconductor sealants, and semiconductor devices containing cured semiconductor sealants for use in electronic components. Furthermore, it can also be widely used in applications other than electronic components, such as coatings, adhesives, and molded articles.

[0063] When the curable composition of the present invention is used for applications such as prepregs, circuit boards, and extension films, it is generally preferred to use it after dilution with an organic solvent. Examples of such organic solvents include: methyl ethyl ketone, acetone, dimethylformamide, methyl isobutyl ketone, methoxypropanol, cyclohexanone, methyl cellosolve, ethyl diethylene glycol acetate, and propylene glycol monomethyl ether acetate. The type or amount of organic solvent can be adjusted appropriately according to the application environment of the curable composition. For example, in applications such as prepregs (circuit boards), polar solvents with a boiling point below 160°C, such as methyl ethyl ketone, acetone, and dimethylformamide, are preferred, and it is preferable to use them at a ratio of 40% to 80% by mass of non-volatile components. In applications involving the formation of thickened membranes, it is preferable to use ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone; acetate solvents such as ethyl acetate, butyl acetate, cellosol acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitol solvents such as cellosol and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; and solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone, preferably with the non-volatile components comprising 30% to 60% by mass.

[0064] The cured product of the present invention can be obtained by curing the curable composition of the present invention. The curing method is not particularly limited and known methods can be used. The cured product can take the form of a laminate, casting, adhesive layer, coating, film, etc.

[0065] The prepreg of the present invention may have a reinforcing substrate and a semi-cured product of the curable composition of the present invention impregnated in the reinforcing substrate. The method for obtaining the prepreg using the curable composition of the present invention is not particularly limited, but can be exemplified by the following method: impregnating the curable composition, which has been varnished with the organic solvent, into a reinforcing substrate (e.g., paper, glass cloth, glass nonwoven fabric, aramid paper, aramid cloth, glass mat, glass roving, etc.), and then heating it at a temperature corresponding to the type of solvent used (preferably 50°C to 170°C) to semi-cur (or not cure) the curable composition.

[0066] There is no particular limitation on the mass ratio of the curing component to the reinforcing substrate used, but it is preferred to prepare the prepreg with the resin component in the prepreg being 20% ​​to 60% by mass.

[0067] A semi-cured product of the curing component can be obtained by adjusting the heating temperature and heating time and stopping the process midway before the curing reaction is complete. The degree of curing of the semi-cured product can be set, for example, to be between 85% and 5%. Here, the cured product can have a higher degree of curing than the semi-cured product. The degree of curing of the semi-cured product can be calculated by measuring the heat of curing when heating the curing component and the heat of curing of its semi-cured product using a differential scanning calorimeter (DSC) and then using the following formula.

[0068] Degree of hardening (%) = [1 - (calorific value of the semi-hardened component / calorific value of the hardened component)] × 100

[0069] The circuit board of the present invention includes a laminate comprising the prepreg and copper foil of the present invention. The method for obtaining the circuit board is not particularly limited; for example, the following method can be used: the prepreg of the present invention is laminated as needed, and the copper foil is overlapped and heated and pressed at 170°C to 300°C under a pressure of 1 MPa to 10 MPa for 10 minutes to 3 hours.

[0070] The build-up film of the present invention contains the curable composition of the present invention. The method of manufacturing the build-up film is not particularly limited; for example, the following method can be used: coating the disclosed curable composition onto a support film to form a curable composition layer, thereby producing an adhesive film for multilayer printed circuit boards.

[0071] The laminated film needs to be softened under the lamination temperature conditions (usually 70°C to 140°C) in the vacuum lamination process. While laminating the circuit board, it should exhibit the fluidity (resin flow) to fill the vias or holes present in the circuit board. Therefore, in order to exhibit this characteristic, the curing composition is preferably a mixture of the inorganic filler, organic solvent, and other components.

[0072] Here, the diameter of the through-holes in the circuit board is typically 0.1mm to 0.5mm, and the depth is typically 0.1mm to 1.2mm. It is generally preferred that resin filling be performed within these ranges. Furthermore, in the case of laminating both sides of the circuit board, it is ideal to fill approximately half of the through-holes.

[0073] Specifically, the method for manufacturing the adhesive film described above can be carried out by the following steps: after preparing the varnish-like curable composition, the varnish-like composition is coated on the surface of the support film (Y), and then the organic solvent is dried by heating or blowing hot air to form a composition layer (X) containing the curable composition.

[0074] The thickness of the formed constituent layer (X) is preferably greater than or equal to the thickness of the conductor layer. The thickness of the conductor layer in the circuit board is typically in the range of 5 μm to 70 μm; therefore, the thickness of the resin constituent layer is preferably 10 μm to 100 μm. Furthermore, the constituent layer (X) can also be protected by a protective film, as described later. By using a protective film, the adhesion or damage of dust and other contaminants to the surface of the resin constituent layer can be prevented.

[0075] The support film (Y) and protective film mentioned above can be categorized as follows: polyolefins such as polyethylene, polypropylene, and polyvinyl chloride; polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET"), polyethylene naphthalate, polycarbonate, and polyimide; and further examples include release paper or metal foils such as copper foil and aluminum foil. Furthermore, in addition to matte treatment and corona treatment, the support film and protective film can also undergo release treatment. The thickness of the support film is not particularly limited, typically ranging from 10 μm to 150 μm, preferably within the range of 25 μm to 50 μm. Additionally, the thickness of the protective film is preferably set to 1 μm to 40 μm.

[0076] The aforementioned support film (Y) is peeled off after being laminated onto the circuit board or after forming an insulating layer by heat curing. Peeling off the support film (Y) after the adhesive film has been heat-cured prevents dust and other contaminants from adhering during the curing process. When peeling off after curing, the support film is usually pre-molded.

[0077] The semiconductor sealing material of the present invention contains the curable composition of the present invention. The curable composition of the present invention has excellent properties such as low curing shrinkage and low dielectric loss tangent in the cured material. In addition, it has excellent compatibility even when formulated with hydrocarbon resins with very low polarity, thus forming a uniform curable composition and obtaining a uniform cured material, and therefore can also be preferably used in semiconductor sealing materials.

[0078] As described above, the semiconductor sealant of the present invention preferably contains an inorganic filler in the curable composition of the present invention. Furthermore, various additives can be incorporated into the semiconductor sealant of the present invention; examples of such additives are described in relation to the curable composition.

[0079] There is no particular limitation on the method for manufacturing the semiconductor sealing material of the present invention. It can be obtained by mixing the curable component of the present invention with various additives as needed. For example, methods such as using an extruder, kneader, roller, etc. to fully melt and mix until it becomes uniform can be listed.

[0080] The semiconductor device disclosed herein includes a cured form of the semiconductor sealing material of the present invention as described above. The semiconductor device of the present invention can be obtained by heat curing the semiconductor sealing material of the present invention, for example, by methods such as casting or molding using a transfer molding machine, injection molding machine, etc., and then heat curing at a temperature range of room temperature (20°C) to 250°C.

[0081] The cured products obtained from the curing composition of this invention exhibit high uniformity and low dielectric loss tangent, making them ideally suited for use in electronic components. They are particularly suitable for use in prepregs, circuit boards, extension films, extension substrates, semiconductor sealants, semiconductor devices, conductive pastes, etc. The electronic components thus obtained can be ideally used for a wide variety of applications, including, but not limited to, industrial machinery parts, general machinery parts, automotive / railway / vehicle parts, aerospace-related parts, electronic / electrical parts, building materials, container / packaging components, consumer goods, sports / leisure products, and wind power generation frame components. [Example]

[0082] The present invention has been specifically described through examples and comparative examples, but the present invention is not limited to these examples. Furthermore, the measurement conditions for GPC in this embodiment are as follows.

[0083] [GPC Measurement Conditions]

[0084] Measurement device: HLC-8320 GPC manufactured by Tosoh Corporation.

[0085] Tube String: Protective tube string "HXL-L" manufactured by Tosoh Corporation.

[0086] +TSK-GEL G4000HXL manufactured by Tosoh Corporation

[0087] +TSK-GEL G3000HXL manufactured by Tosoh Corporation

[0088] +TSK-GEL G2000HXL manufactured by Tosoh Corporation

[0089] +The "TSK-GEL G2000HXL" detector manufactured by Tosoh Corporation: RI (Differential Refractometer)

[0090] Data processing: GPC Workstation EcoSEC Workstation manufactured by Tosoh Corporation.

[0091] Assay conditions: column temperature 40℃, developing solvent tetrahydrofuran, flow rate 1.0 ml / min

[0092] Standard: According to the determination guidelines of "GPC-8320", monodisperse polystyrene with known molecular weight shall be used.

[0093] (The polystyrene used)

[0094] The "A-500" manufactured by Tosoh Corporation

[0095] The "A-1000" manufactured by Tosoh Corporation

[0096] The "A-2500" manufactured by Tosoh Corporation

[0097] The "A-5000" manufactured by Tosoh Corporation

[0098] The F-1 fighter jet manufactured by Tosoh Corporation.

[0099] The F-2 manufactured by Tosoh Corporation

[0100] The F-4 manufactured by Tosoh Corporation

[0101] The F-10 manufactured by Tosoh Corporation

[0102] The F-20 manufactured by Tosoh Corporation

[0103] The F-40 manufactured by Tosoh Corporation

[0104] The F-80 manufactured by Tosoh Corporation

[0105] The F-128 manufactured by Tosoh Corporation.

[0106] Sample: 50 μl of a tetrahydrofuran solution (converted to 1.0% by mass of resin solids) obtained by microfiltration.

[0107] (Manufacturing Example 1: Manufacturing of Active Ester Resin (1))

[0108] Add 1135.4 parts by mass of p-pentylphenol, 461.5 parts by mass of toluene, and 2.3 parts by mass of p-toluenesulfonic acid monohydrate to a flask equipped with a thermometer, dropping funnel, cooling tube, fractionating tube, and stirrer. While stirring, heat the contents of the flask to 120°C. At 120°C, while monitoring for heat generation, add 300.0 parts by mass of divinylbenzene (DVB-810, manufactured by Nippon Steel Chemical & Materials Co., Ltd., with a divinylbenzene purity of 81% by mass). After the addition is complete, stir at the same temperature for 1 hour to allow the reaction to proceed. After the reaction is complete, cool to 80°C, add 1.0 part by mass of 49% sodium hydroxide aqueous solution for neutralization, and then cool to 25°C.

[0109] Subsequently, 699.2 parts by mass of isophthalic acid chloride, 3302.3 parts by mass of toluene, and 2.8 parts by mass of tetrabutylammonium bromide were added. The reaction system was controlled below 60°C, and 1426.2 parts by mass of 20% sodium hydroxide aqueous solution were added dropwise over 3 hours. After the addition was completed, stirring was continued for 1 hour to allow the reaction to proceed. After the reaction was completed, the reaction mixture was allowed to stand and separated to remove the aqueous layer. Water was added to the remaining organic layer and stirred for about 15 minutes. The mixture was then allowed to stand and separated to remove the aqueous layer. The above operation was repeated until the pH of the aqueous layer reached 7. Then, toluene and other substances were distilled off under heating and reduced pressure to obtain the active ester resin (1). The functional group equivalent of the active ester resin (1) was calculated to be 272 g / equivalent based on the added ratio. The GPC diagram of the obtained active ester resin (1) is shown in Figure 1.

[0110] (Manufacturing Example 2: Manufacturing of Active Ester Resin (2))

[0111] Add 333.3 parts by mass of p-tert-octylphenol, 107.8 parts by mass of toluene, and 0.54 parts by mass of p-toluenesulfonic acid monohydrate to a flask equipped with a thermometer, dropping funnel, cooling tube, fractionating tube, and stirrer. While stirring, heat the contents of the flask to 120°C. At 120°C, while monitoring for heat generation, add 70.0 parts by mass of divinylbenzene (DVB-810, manufactured by Nippon Steel Chemical & Materials Co., Ltd., with a divinylbenzene purity of 81% by mass). After the addition is complete, stir at the same temperature for 1 hour to allow the reaction to proceed. After the reaction is complete, cool to 80°C, add 0.23 parts by mass of 49% sodium hydroxide aqueous solution for neutralization, and then cool to 25°C.

[0112] Subsequently, 163.2 parts by mass of isophthalic acid chloride, 907.2 parts by mass of toluene, and 0.8 parts by mass of tetrabutylammonium bromide were added. The reaction system was controlled below 60°C, and 332.8 parts by mass of 20% sodium hydroxide aqueous solution were added dropwise over 3 hours. After the addition was completed, stirring was continued for 1 hour to allow the reaction to proceed. After the reaction was completed, the reaction mixture was allowed to stand and separated to remove the aqueous layer. Water was added to the remaining organic layer and stirred for about 15 minutes. The mixture was allowed to stand and separated to remove the aqueous layer. The above operation was repeated until the pH of the aqueous layer reached 7. Then, toluene and other substances were distilled off under heating and reduced pressure to obtain the active ester resin (2). The functional group equivalent of the active ester resin (2) was calculated to be 314 g / equivalent based on the added ratio. The GPC diagram of the obtained active ester resin (2) is shown in Figure 2.

[0113] (Comparative manufacturing example 1: Manufacturing of reactive ester resin (1'))

[0114] Add 131.7 parts by mass of p-tert-butylphenol, 58.5 parts by mass of toluene, and 0.3 parts by mass of p-toluenesulfonic acid monohydrate to a flask equipped with a thermometer, dropping funnel, cooling tube, fractionating tube, and stirrer. While stirring, heat the contents of the flask to 120°C. At 120°C, while monitoring for heat generation, add 38.0 parts by mass of divinylbenzene ("DVB-810" divinylbenzene manufactured by Nippon Steel Chemical & Materials Co., Ltd., with a purity of 81% by mass). After the addition is complete, stir at the same temperature for 1 hour to allow the reaction to proceed. After the reaction is complete, cool to 80°C, add 0.1 parts by mass of 49% sodium hydroxide aqueous solution for neutralization, and then cool to 25°C.

[0115] Subsequently, 88.6 parts by mass of isophthalic acid chloride, 394.1 parts by mass of toluene, and 0.3 parts by mass of tetrabutylammonium bromide were added. The reaction system was controlled below 60°C, and 180.7 parts by mass of 20% sodium hydroxide aqueous solution were added dropwise over 3 hours. After the addition was completed, stirring was continued for 1 hour to allow the reaction to proceed. After the reaction was completed, the reaction mixture was allowed to stand and separated to remove the aqueous layer. Water was added to the remaining organic layer and stirred for about 15 minutes. The mixture was then allowed to stand and separated to remove the aqueous layer. The above operation was repeated until the pH of the aqueous layer reached 7. Then, toluene and other components were distilled off under heating and reduced pressure to obtain the active ester resin (1'). The functional group equivalent of the active ester resin (1') was calculated to be 258 g / equivalent based on the added ratio. The GPC diagram of the obtained active ester resin (1') is shown in Figure 3.

[0116] (Example 1: Preparation of hardening component (1))

[0117] A 70% toluene solution obtained by dissolving 44 parts by mass of the active ester resin (1) obtained in manufacturing example 1 in toluene, a curing agent (EPICLON 850-S manufactured by DIC Corporation), 31 parts by mass of bisphenol A type epoxy resin, a 20% toluene solution obtained by dissolving 25 parts by mass of hydrocarbon resin (Tuftec H1221 manufactured by Asahi Kasei Corporation; SESB) in toluene, and 1.5 parts by mass of epoxy resin curing agent (Curezol 1B2MZ manufactured by Shikoku Chemical Industry Co., Ltd.) were uniformly mixed to obtain a curable composition (1).

[0118] (Example 2: Preparation of hardening component (2))

[0119] A 70% toluene solution obtained by dissolving 47 parts by mass of the active ester resin (2) obtained in manufacturing example 2 in toluene, a curing agent (EPICLON 850-S manufactured by DIC Corporation), 28 parts by mass of bisphenol A type epoxy resin, a 20% toluene solution obtained by dissolving 25 parts by mass of hydrocarbon resin (Tuftec H1221 manufactured by Asahi Kasei Corporation; SESB) in toluene, and 1.5 parts by mass of epoxy resin curing agent (Curezol 1B2MZ manufactured by Shikoku Chemical Industry Co., Ltd.) were uniformly mixed to obtain a curable composition (2).

[0120] (Comparative Example 1: Preparation of hardening composition (1'))

[0121] A 70% by mass toluene solution obtained by dissolving 43 parts by mass of the active ester resin (1') obtained in comparative manufacturing example 1 in toluene, a curing agent (EPICLON 850-S manufactured by DIC Co., Ltd.), 32 parts by mass of bisphenol A type epoxy resin, a 20% by mass toluene solution obtained by dissolving 25 parts by mass of hydrocarbon resin (Tuftec H1221 manufactured by Asahi Kasei Co., Ltd.; SESB) in toluene, and 1.5 parts by mass of epoxy resin curing agent (Curezol 1B2MZ manufactured by Shikoku Chemical Industry Co., Ltd.) were uniformly mixed to obtain a curable composition (1').

[0122] The following evaluation was conducted using the curing composition (1), curing composition (2), and curing composition (1') obtained in Examples 1, 2, and 1 Comparative Example.

[0123] [Compatibility evaluation of varnish]

[0124] Each hardening component was diluted with toluene to bring the total non-volatile content to 30% by mass, thereby preparing a varnish. The appearance of the prepared varnish was visually observed, and its compatibility was evaluated according to the following criteria.

[0125] ○: A solution that satisfies both homogeneity and transparency.

[0126] ×: A solution that does not meet at least one of the requirements of homogeneity and transparency.

[0127] [Determination of dielectric loss tangent]

[0128] For each curing component, toluene was removed by vacuum distillation at 100°C for 5 minutes using a rotary evaporator. The cured components, after toluene removal, were then pressed at 180°C for 30 minutes to harden and shape, followed by heating at 200°C for 3 hours to obtain test pieces. The dielectric loss tangent at 10 GHz was measured on the obtained test pieces according to JIS-C-6481 using an impedance material analyzer "HP4291B" manufactured by Agilent Technologies, Inc.

[0129] The composition and evaluation results of the curing components (1), (2), and (1') obtained in Examples 1, 2, and Comparative Example 1 are shown in Table 1. Furthermore, the compositions recorded in Table 1 are based on the amount of non-volatile components per 100% by mass.

[0130]

[0131] It was confirmed that the hardening composition of the present invention in Examples 1 and 2 has excellent compatibility and low dielectric loss tangent.

[0132] On the other hand, the curing composition of Comparative Example 1 is an example of a curing composition in which the alkyl group of a compound having alkyl and phenolic hydroxyl groups has less than 5 carbon atoms, and which uses the active ester resin used as a raw material in the curing composition. It was confirmed that the curing composition of Comparative Example 1 has poor compatibility and a slightly higher dielectric loss tangent than the curing composition of the present invention.

Claims

1. A curable composition comprising an active ester resin, a hydrocarbon resin, and a curing agent, wherein the active ester resin is a reaction product of a resin (A) having phenolic hydroxyl groups and an aromatic dicarboxylic acid or its acid halide (B), the resin (A) having phenolic hydroxyl groups is a reaction product of an alkyl compound (a1) having 5 or more carbon atoms and a phenolic hydroxyl group and a divinyl compound (a2), the divinyl compound (a2) being a compound represented by any one of the following general formulas (1-1) to (1-4), and the curing agent being an epoxy resin, wherein in general formulas (1-1) to (1-4), R1 is independently an aliphatic hydrocarbon group, an alkoxy group, a halogen atom, an aryl group, or an aralkyl group, Y is an alkyl group having 1 to 4 carbon atoms, an oxygen atom, a sulfur atom, or a carbonyl group, i is 0 or an integer from 1 to 4, and j is an integer from 1 to 4.

2. The curable composition as claimed in claim 1, wherein the resin (A) having phenolic hydroxyl groups has a structure represented by the following general formula (2), in which X is represented by any one of the following general formulas (X-1) to (X-4), in which R1 is independently an aliphatic hydrocarbon group, alkoxy group, halogen atom, aryl group, aralkyl group, Y is an alkyl group with 1 to 4 carbon atoms, oxygen atom, sulfur atom, carbonyl group, i is 0 or an integer from 1 to 4, and j is an integer from 1 to 4.

3. A hardened material, which is a hardened composition as described in claim 1 or claim 2.

4. A prepreg having a reinforcing substrate and a semi-cured material impregnated therein with a curable composition as described in claim 1 or claim 2.

5. A circuit board comprising a prepreg and copper foil as described in claim 4.

6. A layering membrane comprising a curable composition as described in claim 1 or claim 2.

7. A semiconductor sealing material comprising a curable composition as described in claim 1 or claim 2.

8. A semiconductor device comprising a hardened form of the semiconductor sealing material as described in claim 7.