Curable composition and cured product thereof

Abstract

Provided is a curable composition that produces a cured product that is less prone to warping during curing and has excellent light transmittance. [Solution] Formula (A): HSi(CH3)2-R 1 A curable composition comprising: an addition reaction product of an organosilicon compound represented by -Si(CH3)2H with either or both of an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2), the addition reaction product having a SiH group; (B) a linear organopolysiloxane having silicon-bonded alkenyl groups at both molecular chain terminals; and (C) a hydrosilylation reaction catalyst. TIFF2026038302000034.tif80164

Description

[Technical Field]

[0001] The present invention relates to a curable composition, a cured product thereof, and a film having a layer made of the cured product. [Background technology]

[0002] Thin film materials made of various metals, polyimide, glass, PET, etc. are widely used for general purposes, and these film materials are often used by laminating the same or different types of film materials together. When laminating film materials, a thermosetting composition is generally used as an adhesive, but when the film is thin, warping can occur during curing of the curable composition used for lamination, which can have an adverse effect on the physical properties of the film.

[0003] One approach to combat warpage during curing is to fill the composition with a filler that changes little in volume (Patent Document 1). However, such fillers reduce transparency after curing. This makes them unsuitable for laminating films for optical applications, which require transparency. Furthermore, even if warpage is reduced by using a soft gel-like material, the gel material is generally prone to deformation due to stress after lamination, so an adhesive material with high hardness is desired. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-136418 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made to solve the above problems, and an object of the present invention is to provide a curable composition that produces a cured product with little warping during curing and excellent light transmittance. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides (A) an addition reaction product of an organosilicon compound represented by the following formula (1) with either or both of an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2), wherein the addition reaction product has a SiH group: [ka] (In the formula, R 1 are independently substituted or unsubstituted divalent hydrocarbon groups having 1 to 12 carbon atoms. [ka] (In the formula, R 2 are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms and containing no aliphatic unsaturated bonds, and R 3 are independently an alkenyl group having 2 to 8 carbon atoms, and k is independently 1 or 2. (B) a linear organopolysiloxane having silicon-bonded alkenyl groups at both molecular chain terminals (excluding the organosilicon compound represented by formula (2-2) above), and (C) Hydrosilylation reaction catalyst A curable composition comprising: the SiH group content of the component (A) is 0.0030 to 0.0050 mol / g, The curable composition is characterized in that the molar ratio of SiH groups to silicon-bonded alkenyl groups in the curable composition is 0.80 or less.

[0007] The curable composition of the present invention can provide a curable composition that produces a cured product that is less prone to warping during curing and has excellent light transmittance.

[0008] The curable composition of the present invention is 1 is a phenylene group, and the R 2 is a methyl group or a phenyl group, and the R 3 is preferably a vinyl group.

[0009] The organosilicon compounds represented by the above formula (1), the organosilicon compounds represented by the above formula (2-1), and the organic compounds represented by the above formula (2-2) are easily available, and the addition reaction product thereof, component (A), can be efficiently obtained.

[0010] In the curable composition of the present invention, the component (B) is preferably an organopolysiloxane represented by the following formula (3). [ka] (In the formula, R 4 are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms, and R 5 are independently a methyl group or a phenyl group, a is an integer of 0 to 50, and b is an integer of 0 to 100. However, when a is 0, R 5 is a phenyl group, and b is 1 to 100. The siloxane units in parentheses may be arranged in any order.

[0011] Such component (B) can be easily obtained.

[0012] In the curable composition of the present invention, the alkenyl group content of the component (B) is preferably 0.20 to 0.50 mol / 100 g.

[0013] Such component (B) provides a cured product with little warping during curing and excellent mechanical properties.

[0014] The present invention also provides a cured product obtained by curing the above curable composition.

[0015] The cured product of the present invention exhibits little warping during curing and excellent light transmittance, and can be suitably used for applications such as bonding transparent films together.

[0016] The present invention further provides a film having a layer made of the above cured product.

[0017] The film of the present invention has high reliability because the cured product used has high light transmittance and little warping. [Effects of the Invention]

[0018] The curable composition of the present invention can provide a cured product that has excellent light transmittance and little warping after curing, and is therefore useful as an adhesive for laminating thin films or transparent film materials, and also as a coating material. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic diagram of a warpage test. DETAILED DESCRIPTION OF THE INVENTION

[0020] As described above, there has been a need for the development of a curable composition that gives a cured product that has excellent light transmittance and little warping.

[0021] As a result of extensive research into the above-mentioned problems, the present inventors have found that a curable composition containing specific components can solve the above-mentioned problems, and have thus completed the present invention.

[0022] That is, the present invention provides: (A) An addition reaction product of an organosilicon compound represented by the following formula (1) with either or both of an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2), which has a SiH group: [ka] (In the formula, R 1 are independently substituted or unsubstituted divalent hydrocarbon groups having 1 to 12 carbon atoms. [ka] (In the formula, R 2are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms and containing no aliphatic unsaturated bonds, and R 3 are independently an alkenyl group having 2 to 8 carbon atoms, and k is independently 1 or 2. (B) a linear organopolysiloxane having silicon-bonded alkenyl groups at both molecular chain terminals (excluding the organosilicon compound represented by formula (2-2) above), and (C) Hydrosilylation reaction catalyst A curable composition comprising: the SiH group content of the component (A) is 0.0030 to 0.0050 mol / g, The curable composition is characterized in that the molar ratio of SiH groups to silicon-bonded alkenyl groups in the curable composition is 0.80 or less.

[0023] The present invention will be described in detail below, but the present invention is not limited thereto. In this specification, the descriptions using endpoints of numerical ranges include all values ​​included in that range.

[0024] [Curable composition] The curable composition of the present invention is an addition-curable silicone composition containing the following components (A) to (C): The curable composition of the present invention can be prepared by mixing the following components (A) to (C) and, if necessary, other components, by a conventionally known method. Each component will be described in detail below.

[0025] [Component (A)] The component (A) in the curable composition of the present invention is an addition reaction product having a SiH group, and functions as a crosslinking agent by undergoing a hydrosilylation reaction with the component (B) described below.

[0026] Component (A) is an addition reaction product of an organosilicon compound represented by the following formula (1) with either or both of an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2), and is an addition reaction product having a SiH group.

[0027] Component (A) is preferably (i) an addition reaction product of an organosilicon compound represented by the following formula (1) with an organosilicon compound represented by the following formula (2-1), or (ii) an addition reaction product of an organosilicon compound represented by the following formula (1), with an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2).

[0028] [ka] (In the formula, R 1 are independently substituted or unsubstituted divalent hydrocarbon groups having 1 to 12 carbon atoms. [ka] (In the formula, R 2 are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms and containing no aliphatic unsaturated bonds, and R 3 are independently an alkenyl group having 2 to 8 carbon atoms, and k is independently 1 or 2.

[0029] R 1 Examples of the divalent hydrocarbon group having 1 to 12 carbon atoms represented by the formula (I) include alkylene groups such as methylene, ethylene, n-propylene, n-butylene, n-pentylene, n-hexylene, cyclohexylene, and n-octylene, arylene groups such as phenylene and naphthylene, and groups in which some or all of the hydrogen atoms of these groups have been substituted with halogen atoms such as fluorine, bromine, and chlorine. 1 As the alkyl group, a phenylene group is particularly preferred.

[0030] R 2Examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms represented by the formula (I) include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, and octyl; cycloalkyl groups such as cyclohexyl; alkenyl groups such as vinyl, allyl, and propenyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups such as benzyl, phenylethyl, and phenylpropyl; and groups in which some or all of the hydrogen atoms of these groups have been substituted with halogen atoms such as fluorine, bromine, and chlorine. 2 As the alkyl group, a methyl or phenyl group is preferred, and a phenyl group is particularly preferred.

[0031] R 3 Examples of the alkenyl group having 2 to 8 carbon atoms represented by R include a vinyl group, an allyl group, a 3-butenyl group, a 5-hexenyl group, and a 7-octenyl group. 3 As the alkyl group, a vinyl group is particularly preferred.

[0032] Specific examples of suitable organosilicon compounds represented by the above formula (1) are shown below, but are not limited to these. The organosilicon compounds represented by the above formula (1) can be used singly or in combination of two or more. [ka]

[0033] Specific examples of suitable organosilicon compounds represented by the above formula (2-1) are shown below, but are not limited to these. The compounds represented by the above formula (2-1) can be used singly or in combination of two or more. [ka]

[0034] Specific examples of suitable organosilicon compounds represented by the above formula (2-2) are shown below, but are not limited to these. The compounds represented by the above formula (2-2) can be used singly or in combination of two or more. [ka]

[0035] As component (A), an organosilicon compound represented by formula (2-1) above and an organosilicon compound represented by formula (2-2) above, in which SiH groups of the organosilicon compound represented by formula (1) above are added to all alkenyl groups, are preferred. Specific examples include, but are not limited to, compounds represented by the following formulas: [ka] (In the formula, n is an integer of 1 to 10, and the dashed lines represent bonds to adjacent atoms.) [ka] (In the formula, p and q are integers of 1 to 10, and the dashed lines represent bonds to adjacent atoms.)

[0036] The component (A) can be used either alone or in combination of two or more.

[0037] The presence of SiH groups in the addition reaction product constituting component (A) can be confirmed by selecting an appropriate measurement method. When component (A) is made up of two or more compounds, a combination of appropriate measurement methods (e.g., 1 The amount of SiH groups in the addition reaction product can be confirmed by selecting the appropriate NMR spectroscopy (H-NMR and GPC, etc.).

[0038] The SiH group content of component (A) is 0.0030 to 0.0050 mol / g. If the SiH group content is less than 0.0030 mol / g, the crosslinking component will be insufficient, resulting in reduced mechanical strength. If the SiH group content exceeds 0.0050 mol / g, the crosslinking component will be excessive, resulting in significant shrinkage during curing, causing the resin to warp significantly and even become curled. The SiH group content is preferably 0.0030 to 0.0040 mol / g, and more preferably 0.0034 to 0.0035 mol / g. Within this range, the cured product will have minimal warpage during curing and excellent mechanical properties.

[0039] [Preparation of component (A)] The component (A) in the curable composition of the present invention can be obtained by mixing the organosilicon compound represented by the above formula (2-1) and the organosilicon compound represented by the above formula (2-2) so that the amount of SiH groups in the compound represented by the above formula (1) is more than 2 moles and not more than 50 moles, more preferably more than 5 moles and not more than 30 moles, per mole of alkenyl groups in the compound represented by the above formula (2-1), carrying out a hydrosilylation reaction, and then removing any unreacted material, if necessary, by concentration under reduced pressure or the like.

[0040] The catalyst used in the hydrosilylation reaction may be a known one. Examples include platinum-based catalysts such as platinum metal-supported carbon powder, platinum black, platinic chloride, chloroplatinic acid, reaction products of chloroplatinic acid and monohydric alcohols, complexes of chloroplatinic acid and olefins, and platinum bisacetoacetate; and platinum group metal catalysts such as palladium-based catalysts and rhodium-based catalysts. The addition reaction conditions, purification conditions, and solvents used are not particularly limited, and known methods may be used.

[0041] [(B) Component] Component (B) in the curable composition of the present invention is a linear organopolysiloxane having silicon-bonded alkenyl groups at both molecular chain terminals, and is a linear organopolysiloxane other than the organosilicon compound represented by formula (2-2). Component (B) undergoes an addition reaction with component (A) in the presence of the hydrosilylation reaction catalyst (C) described below.

[0042] Examples of alkenyl groups bonded to silicon atoms include vinyl groups, allyl groups, 3-butenyl groups, 5-hexenyl groups, and 7-octenyl groups, with vinyl groups being preferred. The bonding positions of the alkenyl groups in the linear organopolysiloxane molecular chain may include bonding to silicon atoms within the molecular chain in addition to the silicon atoms at both ends of the molecular chain, but it is preferred that they be bonded only to silicon atoms at both ends of the molecular chain.

[0043] Specific examples of component (B) include, but are not limited to, polyorganosiloxanes in which both molecular chain terminals are capped with trivinylsiloxy groups, methyldivinylsiloxy groups, or dimethylvinylsiloxy groups. Examples include polydimethylsiloxanes capped at both molecular chain terminals with trivinylsiloxy groups, polydiphenylsiloxanes capped at both molecular chain terminals with trivinylsiloxy groups, dimethylsiloxane-methylvinylsiloxane copolymers capped at both molecular chain terminals with trivinylsiloxy groups, and dimethylsiloxane-diphenylsiloxane-methylvinylsiloxane copolymers capped at both molecular chain terminals with trivinylsiloxy groups, and polyorganosiloxanes capped at both molecular chain terminals with trivinylsiloxy groups, such as methyldivinylsiloxy groups. End-blocked polydimethylsiloxane, end-blocked polydiphenylsiloxane with methyldivinylsiloxy groups, end-blocked dimethylsiloxane-methylvinylsiloxane copolymer with methyldivinylsiloxy groups, end-blocked dimethylsiloxane-diphenylsiloxane-methylvinylsiloxane copolymer with methyldivinylsiloxy groups, end-blocked polyorganosiloxane with methyldivinylsiloxy groups, end-blocked polydimethylsiloxane with dimethylvinylsiloxy groups, Polyorganosiloxanes capped at both molecular chain ends with dimethylvinylsiloxy groups, such as polydiphenylsiloxanes capped at both molecular chain ends with dimethylvinylsiloxy groups, dimethylsiloxane-diphenylsiloxane copolymers capped at both molecular chain ends with dimethylvinylsiloxy groups, and dimethylsiloxane-diphenylsiloxane-methylvinylsiloxane copolymers capped at both molecular chain ends with dimethylvinylsiloxy groups, polydimethylsiloxanes capped at both molecular chain ends with methylphenylvinylsiloxy groups, and polyorganosiloxanes capped at both molecular chain ends with methylvinylsiloxy groups. Examples include polyorganosiloxanes capped at both molecular chain ends with methylphenylvinylsiloxy groups, such as polydiphenylsiloxane capped at both molecular chain ends with methylphenylvinylsiloxy groups, dimethylsiloxane-diphenylsiloxane copolymers capped at both molecular chain ends with methylphenylvinylsiloxy groups, and dimethylsiloxane-diphenylsiloxane-methylvinylsiloxane copolymers capped at both molecular chain ends with methylphenylvinylsiloxy groups.The degree of polymerization (number of basic siloxane units in the molecule) of these is preferably 3 to 200. The component (B) can be used either individually or in combination of two or more.

[0044] Component (B) is preferably a linear organopolysiloxane represented by the following formula (3). [ka] (In the formula, R 4 are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms, and R 5 are independently a methyl group or a phenyl group, a is an integer of 0 to 50, and b is an integer of 0 to 100. However, when a is 0, R 5 is a phenyl group, and b is 1 to 100. The siloxane units in parentheses may be arranged in any order.

[0045] R 4 Examples of the unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms represented by the formula (I) include alkyl groups having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, and t-butyl; haloalkyl groups having 1 to 4 carbon atoms, such as chloromethyl and 3,3,3-trifluoropropyl; aryl groups having 6 to 10 carbon atoms, such as phenyl and tolyl; and alkenyl groups, such as vinyl and allyl. Of these, methyl, phenyl, and vinyl groups are preferred.

[0046] In the above formula (3), a is an integer of 0 to 50, preferably 1 to 10, more preferably 1 to 7, and even more preferably 2 to 4. b is an integer of 0 to 100, preferably 0 to 50, more preferably 0 to 10, and even more preferably 0. However, when a is 0, R 5 is a phenyl group, and b is 1 to 100. The siloxane units in parentheses may be arranged in any order.

[0047] The organopolysiloxane represented by formula (3) can be obtained by, for example, hydrolysis and condensation of a bifunctional silane such as dichlorodiphenylsilane or dialkoxydiphenylsilane, followed by terminal blocking with alkenyl-containing siloxane units, or simultaneously with the hydrolysis and condensation.

[0048] The alkenyl group content in component (B) is preferably 0.10 to 1.0 mol / 100g, and more preferably 0.20 to 0.50 mol / 100g. Within this range, warping during curing is minimal, resulting in a cured product with excellent mechanical properties.

[0049] The amount of component (B) is such that the molar ratio of SiH groups to silicon-bonded alkenyl groups (SiH groups / aliphatic unsaturated groups) in the composition is 0.80 or less, preferably 0.60 to 0.80, and particularly preferably 0.60 to 0.70. If the molar ratio of SiH groups to silicon-bonded alkenyl groups in the curable composition exceeds 0.80, significant warping during curing may occur.

[0050] [(C) component] The hydrosilylation reaction catalyst that is component (C) of the present invention can be the same as that used in preparing component (A) above.

[0051] The amount of component (C) blended into the curable composition of the present invention may be a so-called catalytic amount, but is preferably an amount that corresponds to 1 to 500 ppm, more preferably about 1 to 100 ppm, and even more preferably 2 to 12 ppm, of platinum group metal atoms relative to the total mass of the composition. By blending an amount within this range, the reaction can be sufficiently promoted and discoloration of the cured product can be prevented.

[0052] [Other ingredients] In addition to the above components (A) to (C), the curable composition of the present invention may contain other components such as an antioxidant and an adhesion improver, if necessary.

[0053] [Antioxidants] In the cured product of the curable composition of the present invention, the addition-reactive carbon-carbon double bonds in component (B) may remain unreacted, and these may be oxidized by oxygen in the atmosphere, causing discoloration of the cured product. Therefore, if necessary, such discoloration can be prevented by adding an antioxidant to the curable composition of the present invention.

[0054] Known antioxidants can be used, such as 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-amylhydroquinone, 2,5-di-t-butylhydroquinone, 4,4'-butylidenebis(3-methyl-6-t-butylphenol), 2,2'-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), etc. These can be used either individually or in combination of two or more.

[0055] When this antioxidant is used, its amount is not particularly limited, but it is usually preferably about 1 to 10,000 ppm, and particularly about 10 to 1,000 ppm, based on the total mass of components (A) and (B). By using an amount within this range, the antioxidant ability is fully exerted, and a cured product with excellent optical properties can be obtained without the occurrence of coloration, cloudiness, oxidative degradation, etc.

[0056] [Adhesion improver] The curable composition of the present invention may contain an adhesion improver. Examples of the adhesion improver include a silane coupling agent, an oligomer thereof, and a polysiloxane having the same reactive group as the silane coupling agent.

[0057] The adhesion improver is preferably a compound represented by the following formula (4) or a silane coupling agent having an allyl isocyanurate structure as an organic functional group. [ka] (In the formula, s is an integer of 1 to 3, t is an integer of 0 to 3, and u is an integer of 0 to 3, provided that s+t+u is an integer of 4 or 5. The siloxane units in parentheses may be arranged in any order.)

[0058] An example of a silane coupling agent having an allyl isocyanurate structure as an organic functional group is a compound represented by the following formula (5): where R and R' in the formula apply only to the following formula: [ka] (wherein at least one R' is an allyl group, and the others are hydrogen atoms, alkyl groups, cycloalkyl groups, aryl groups, heteroaryl groups, non-aromatic heterocyclic rings, (CH2)3Si(OR)3, or allyl groups, and R is an alkyl group, cycloalkyl group, aryl group, heteroaryl group, non-aromatic heterocyclic ring, or allyl group.)

[0059] In the above formula, R is preferably a C1-4 alkyl group, more preferably a methyl group or an ethyl group, and R' is preferably (CH2)3Si(OR)3 or an allyl group.

[0060] Specific examples of the silane coupling agent having an allyl isocyanurate structure include X-12-1290 (manufactured by Shin-Etsu Chemical Co., Ltd.) and the compound represented by the following formula: [ka]

[0061] Specific examples of suitable adhesion improvers include, but are not limited to, those represented by the following formula: The adhesion improver may be a commercially available product. [ka] [ka]

[0062] The adhesion improver is an optional component that is blended into the curable composition of the present invention to improve the adhesion of the composition and its cured product to a substrate. Here, the substrate refers to a metal material such as gold, silver, copper, or nickel; a ceramic material such as aluminum oxide, aluminum nitride, or titanium oxide; or a polymer material such as a silicone resin or an epoxy resin. The adhesion improver can be used alone or in combination of two or more.

[0063] When an adhesion improver is used, the blending amount is preferably 1 to 30 parts by mass, and more preferably 1 to 10 parts by mass, per 100 parts by mass of the total of the components (A) and (B). With such a blending amount, the curable composition of the present invention and its cured product effectively improve the adhesion to substrates and are less likely to become discolored.

[0064] [others] In order to ensure a long pot life, an addition reaction inhibitor such as 1-ethynylcyclohexanol or 3,5-dimethyl-1-hexyn-3-ol may be added.

[0065] Furthermore, a light stabilizer can be used to impart resistance to photodegradation caused by light energy from sunlight, fluorescent lamps, etc. Hindered amine stabilizers that capture radicals generated by photooxidative degradation are suitable as light stabilizers, and their antioxidant effect can be further improved by using them in combination with an antioxidant. Specific examples of light stabilizers include bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate and 4-benzoyl-2,2,6,6-tetramethylpiperidine.

[0066] In the curable composition of the present invention, the total amount of components (A), (B) and (C) is preferably 50 to 100 mass%, more preferably 80 to 100 mass%, and even more preferably 90 to 100 mass%. The curable composition of the present invention can be produced by mixing the above-mentioned components to a uniform degree.

[0067] [Cured product] The curable composition of the present invention is cured to obtain the cured product of the present invention. The cured product has excellent light transmittance and little warping after curing. The curing conditions for the curable composition of the present invention are not particularly limited, but are preferably 60 to 180°C and 5 to 300 minutes.

[0068] The cured product obtained from the curable composition of the present invention preferably has a hardness (Shore D, 23°C) of 15 or more at a thickness of 6 mm according to ASTM D 2240. There is no particular upper limit to the hardness, but it can be about 90 Shore D hardness.

[0069] Furthermore, the cured product obtained from the curable composition of the present invention preferably has a light transmittance (23°C) of 85% or more at a wavelength of 400 nm at a thickness of 2 mm. The upper limit of the light transmittance is not particularly limited, but can be about 99%. The light transmittance can be measured using a spectrophotometer.

[0070] The cured product of the present invention having such properties is useful as an adhesive for laminating thin films or transparent film materials, and also as a coating material. [Example]

[0071] EXAMPLES The present invention will be specifically explained below using examples and comparative examples, but the present invention is not limited to these.

[0072] Also, in the following example: 1 H-NMR measurements were performed using a Bruker Biospin AVANCE III. Gel permeation chromatography (GPC) measurements were performed using a Tosoh HLC-8320GPC with tetrahydrofuran (THF) as the mobile phase, converted to standard polystyrene. Viscosity at 25°C was measured using a B-type rotational viscometer in accordance with JIS-K7117-1:1999.

[0073] [Synthesis Example 1] A 1 L four-neck flask equipped with a stirrer, condenser, dropping funnel, and thermometer was charged with 262.8 g (1.35 mol) of 1,4-bis(dimethylsilyl)benzene (Shin-Etsu Chemical Co., Ltd.) and 0.12 g of 5% Pt carbon powder (N.E. Chemcat Corporation) and heated to 85 °C using an oil bath. 28.0 g (0.15 mol) of trivinylphenylsilane (Shin-Etsu Chemical Co., Ltd.) was added dropwise. After the addition was complete, the mixture was stirred between 90 and 100 °C for 5 hours. After stirring, the mixture was returned to 25 °C, 2.9 g of activated carbon was added, and the mixture was stirred for 1 hour. After stirring, the mixture was filtered and concentrated under reduced pressure to obtain 99.7 g of component (A-1) (colorless, transparent, 87% yield, viscosity at 25 °C: 30 Pa s).

[0074] The reaction product 1 Analysis by H-NMR, GPC, etc. revealed that this was a mixture of compounds having structures represented by the following formulas (a) to (d), with the ratio of each compound being (a):(b):(c):(d) = 55:25:10:10 (mol%). The SiH group content of the entire mixture was 0.0035 mol / g.

[0075] [ka]

[0076] [ka]

[0077] [ka]

[0078] [ka] (In the formula, dashed lines represent bonds to adjacent atoms.)

[0079] [Synthesis Example 2] A 1 L four-neck flask equipped with a stirrer, condenser, dropping funnel, and thermometer was charged with 610.4 g (5.7 mol) of 1,4-bis(dimethylsilyl)benzene (Shin-Etsu Chemical Co., Ltd.) and 0.30 g of 5% Pt carbon powder (N.E. Chemcat Corporation) and heated to 85 °C using an oil bath. 55.8 g (0.3 mol) of trivinylphenylsilane (Shin-Etsu Chemical Co., Ltd.) and 31 g (0.1 mol) of 1,2-dimethyl-1,2-diphenyl-1,2-divinyldisiloxane (Shin-Etsu Chemical Co., Ltd.) were added dropwise. After the addition, the mixture was stirred between 90 and 100 °C for 5 hours. After stirring, the temperature was returned to 25 °C, 10.4 g of activated carbon was added, and the mixture was stirred for 1 hour. After stirring, the mixture was filtered and concentrated under reduced pressure to obtain 279 g of component (A-2) (colorless and transparent, yield 93%, viscosity at 25°C: 15 Pa·s).

[0080] The reaction product 1 Analysis by H-NMR, GPC, etc. revealed that this was a mixture of oligomers having the structure represented by the following formula: The SiH group content of the entire mixture was 0.0034 mol / g. [ka] (In the formula, p and q are integers of 1 to 10, and the dashed lines represent bonds to adjacent atoms.)

[0081] [Examples 1 to 5, Comparative Examples 1 to 4] Curable compositions were prepared by mixing the following components in the proportions (parts by mass) shown in Table 1. In the following examples, the symbols representing siloxane units are as follows. M Vi :(CH2=CH)(CH3)2SiO 1 / 2 M ViΦ :(CH2=CH)(CH3)(C6H5)SiO 1 / 2 M H :H(CH3)2SiO 1 / 2 D 2Φ :(C6H5)2SiO 2 / 2 T Φ:(C6H5)SiO 3 / 2 Q:SiO 4 / 2

[0082] Component (A) (A-1) Reaction product obtained in Synthesis Example 1. (A-2) Reaction product obtained in Synthesis Example 2. (A-3)M H 3T Φ Organohydrogenpolysiloxane represented by formula 1 (SiH group content: 0.0091 mol / g).

[0083] (B) Component (B-1)M ViΦ 2D 2Φ Linear organopolysiloxane represented by formula 3 (vinyl group content: 0.23 mol / 100 g, viscosity at 25°C: 2,000 mPa s) (B-2)M Vi 2D 2Φ A linear organopolysiloxane (vinyl group content: 0.50 mol / 100 g, viscosity: 10 mPa·s at 25°C) represented by the formula (B-3)M ViΦ :D 2Φ : Organopolysiloxane resin having a structural unit ratio of Q = 20:37.5:42.5 (mol %) (vinyl group content: 0.15 mol / 100 g, solid at 25°C)

[0084] (C) Component Platinum 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (diluted in polysiloxane, platinum concentration 1% by mass)

[0085] (D) Component Adhesion improver: a compound represented by the following formula [ka]

[0086] (E) Component Reaction control agent: ethynylcyclohexanol

[0087] [Table 1] In the table, the molar ratio of SiH groups to vinyl groups is the molar ratio of SiH groups to alkenyl groups bonded to silicon atoms in the curable composition.

[0088] <Performance evaluation method> The curable compositions obtained in the above Examples and Comparative Examples were evaluated for physical properties of the cured products according to the following methods. The evaluation results are shown in Table 2.

[0089] (1)Hardness The curable composition was poured into a mold combined with glass plates to a thickness of 2 mm, and post-cured at 150°C for 4 hours to obtain a cured product. Three sheets of each cured product were stacked, and the hardness (Shore D) at a thickness of 6 mm was measured at 23°C according to ASTM D 2240.

[0090] (2) Light transmittance For each of the cured products prepared in the same manner as in the hardness measurement above, the 400 nm light transmittance of each cured product at a thickness of 2 mm was measured at 23°C using a spectrophotometer.

[0091] (3) Warpage after hardening The warpage test (evaluation of warpage after curing) will be explained with reference to Figure 1. First, using a press molding machine, the curable composition was molded to a thickness of 0.3 mm on an aluminum foil measuring 55 mm x 115 mm and 50 μm thick at 150°C for 10 minutes (Figure 1, left). After exposure to 150°C for 4 hours, the warpage of the resin after curing was evaluated by measuring the distance between end points A and B in Figure 1 (Figure 1, right). If there is no warping of the resin, the distance remains unchanged from 55 mm, and the smaller the distance between the end points A and B, the greater the warping. If the aluminum foil is rolled into a cylindrical shape and it is impossible to measure the distance between the end points A and B, it is recorded as "immeasurable."

[0092] [Table 2]

[0093] As shown in Table 2, the cured products of the curable compositions of Examples 1 to 5 had excellent light transmittance and little warping during curing. In particular, in Examples 3 to 5, in which the molar ratio of SiH groups to vinyl groups was 0.70, almost no warping was observed during curing. On the other hand, in Comparative Examples 1 and 2, in which the molar ratio of SiH group / vinyl group exceeded 0.8, warping during curing was very large. H 3T Φ In Comparative Example 3, where the organohydrogenpolysiloxane represented by formula (1) was used, no curing occurred even when the molar ratio of SiH groups to vinyl groups was 0.80. H 3T Φ In Comparative Example 4, in which the organohydrogenpolysiloxane represented by Formula 1 was used and part of component (B) was replaced with an organopolysiloxane resin, a cured product was obtained, but the warpage during curing was very large.

[0094] The present specification includes the following aspects. [1]: (A) an addition reaction product of an organosilicon compound represented by the following formula (1) with either or both of an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2), which has a SiH group; [ka] (In the formula, R 1 are independently substituted or unsubstituted divalent hydrocarbon groups having 1 to 12 carbon atoms. [ka] (In the formula, R 2 are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms and containing no aliphatic unsaturated bonds, and R 3 are independently an alkenyl group having 2 to 8 carbon atoms, and k is independently 1 or 2. (B) a linear organopolysiloxane having silicon-bonded alkenyl groups at both molecular chain terminals (excluding the organosilicon compound represented by formula (2-2) above), and (C) Hydrosilylation reaction catalyst A curable composition comprising: the SiH group content of the component (A) is 0.0030 to 0.0050 mol / g, A curable composition, wherein the molar ratio of SiH groups to silicon-bonded alkenyl groups in the curable composition is 0.80 or less. [2]: The above R 1 is a phenylene group, and the R 2 is a methyl group or a phenyl group, and the R 3 The curable composition according to [1], wherein is a vinyl group. [3]: The curable composition according to [1] or [2], wherein the component (B) is an organopolysiloxane represented by the following formula (3): [ka] (In the formula, R 4 are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms, and R 5 are independently a methyl group or a phenyl group, a is an integer of 0 to 50, and b is an integer of 0 to 100. However, when a is 0, R 5 is a phenyl group, and b is 1 to 100. The siloxane units in parentheses may be arranged in any order. [4]: The curable composition according to any one of [1] to [3], wherein the alkenyl group content of the component (B) is 0.20 to 0.50 mol / 100 g. [5]: A cured product obtained by curing any one of the curable compositions [1] to [4]. [6]: A film characterized by having a layer made of the cured product of [5].

[0095] The present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits similar effects is included within the technical scope of the present invention.

Claims

1. (A) An addition reaction product of an organosilicon compound represented by the following formula (1) with either or both of an organosilicon compound represented by the following formula (2-1) and an organosilicon compound represented by the following formula (2-2), which has a SiH group: 【Chemistry 1】 (In the formula, R １ are independently substituted or unsubstituted divalent hydrocarbon groups having 1 to 12 carbon atoms. 【Chemistry 2】 (In the formula, R ２ are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms and containing no aliphatic unsaturated bonds, and R ３ are independently alkenyl groups having 2 to 8 carbon atoms, and k is independently 1 or 2. (B) a linear organopolysiloxane having silicon-bonded alkenyl groups at both molecular chain terminals (excluding the organosilicon compound represented by formula (2-2) above), and (C) Hydrosilylation reaction catalyst A curable composition comprising: the SiH group content of the component (A) is 0.0030 to 0.0050 mol / g, A curable composition, wherein the molar ratio of SiH groups to silicon-bonded alkenyl groups in the curable composition is 0.80 or less.

2. The R １ is a phenylene group, and the R ２ is a methyl group or a phenyl group, and the R ３ The curable composition according to claim 1, wherein is a vinyl group.

3. 2. The curable composition according to claim 1, wherein the component (B) is an organopolysiloxane represented by the following formula (3): 【Transformation 3】 (In the formula, R ４ are independently unsubstituted or substituted monovalent hydrocarbon groups having 1 to 12 carbon atoms, and R ５ are independently a methyl group or a phenyl group, a is an integer of 0 to 50, and b is an integer of 0 to 100. However, when a is 0, R ５ is a phenyl group, and b is 1 to 100. The siloxane units in parentheses may be arranged in any order.

4. 2. The curable composition according to claim 1, wherein the alkenyl group content of the component (B) is 0.20 to 0.50 mol / 100 g.

5. A cured product obtained by curing the curable composition according to any one of claims 1 to 4.

6. A film comprising a layer made of the cured product according to claim 5.

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