Bicyclic acetylene alcohol compound, addition-curable silicone composition, and thermally conductive addition-curable silicone composition

Abstract

To provide a bicyclic acetylene alcohol compound in which an isomerization reaction to α, β-unsaturated ketone is unlikely to occur, an addition-curable silicone composition containing the compound, and a thermally conductive addition-curable silicone composition.SOLUTION: The present invention provides a bicyclic acetylene alcohol compound characterized in that: a hydroxyl-substituted carbon atom in the compound is a tertiary carbon atom that bonds with an acetylene group and the α-carbon in the compound is a bridged carbon atom; a hydrogen atom is not present on the α-carbon atom; or both of these conditions are satisfied.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a bicyclic acetylene alcohol compound, an addition-curable silicone composition, and a thermally conductive addition-curable silicone composition. [Background technology]

[0002] Addition-curing silicone compositions cure to form silicone gels, silicone rubbers, hard coat films, etc., which have excellent electrical properties, cold resistance, heat resistance, and chemical stability, and are therefore widely used as sealants, fillers, or coating agents for electrical and electronic components and semiconductor elements, optical semiconductor insulating coating protective agents, etc. In addition, by blending various inorganic fillers, it is possible to increase the strength of the composition and impart heat resistance. Furthermore, they are also used as heat dissipation materials and conductive materials for electronic components such as semiconductor elements and LED substrates.

[0003] In order to initiate the curing reaction (hydrosilylation reaction) of an addition curing silicone composition at the desired timing, it is essential to control the pot life and shelf life, and several means for this purpose have been proposed. For example, a microcapsule structure in which a hydrosilylation reaction catalyst is embedded in a polymer compound has been proposed (e.g., Patent Documents 1 and 2). However, the hydrosilylation reaction catalyst embedded inside the microcapsule structure has a slow diffusion rate into the composition, which makes it difficult to initiate the addition curing reaction.

[0004] Another method is to blend an addition curing reaction inhibitor selected from acetylene compounds, nitrogen compounds, organic phosphorus compounds, oxime compounds, organic chloro compounds, etc. (Patent Document 3). By blending an appropriate amount of these addition curing reaction inhibitors, it is possible to control the pot life and shelf life, and to start the curing reaction of the addition curing silicone composition at the desired timing. Acetylene alcohols are often used because they have a low odor and are environmentally friendly.

[0005] As described above, acetylene alcohols are useful as addition curing reaction inhibitors, but they are known to undergo isomerization to α,β-unsaturated ketones in the presence of acid (Meyer-Schuster rearrangement, Rupe rearrangement) (Non-Patent Document 1). The addition curing reaction control ability of the isomerized α,β-unsaturated ketone is greatly reduced, which causes a problem of significantly shortening the pot life and shelf life of the addition curing silicone composition. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 11-236508 [Patent Document 2] JP 2014-024986 A [Patent Document 3] Japanese Patent Application Publication No. 04-046962 [Non-patent literature]

[0007] [Non-Patent Document 1] J. Org. Chem. 1977, 42, 3403 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the present invention has been made in consideration of the above circumstances, and provides an isomerization reaction to an α,β-unsaturated ketone. The object of the present invention is to provide a bicyclic acetylene alcohol compound which is less likely to cause the above-mentioned problems, an addition-curable silicone composition containing said compound, and a thermally conductive addition-curable silicone composition. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides a bicyclic acetylene alcohol compound, in which the carbon atom substituted with a hydroxyl group in the compound is a tertiary carbon atom bonded to an acetylene group, and the α-carbon in the compound is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both are satisfied. Note that the α-carbon in this case refers to the two carbon atoms other than the acetylene group adjacent to the carbon atom substituted with a hydroxyl group.

[0010] Such bicyclic acetylene alcohol compounds are less likely to undergo an isomerization reaction to an α,β-unsaturated ketone, and when incorporated as an addition curing reaction inhibitor in an addition curing silicone composition or a thermally conductive addition curing silicone composition, the pot life or shelf life is less likely to be shortened.

[0011] In the present invention, the minimum number of carbon atoms constituting the ring is preferably 7 or less.

[0012] Such bicyclic acetylene alcohol compounds are less likely to undergo an isomerization reaction to an α,β-unsaturated ketone, and when incorporated as an addition curing reaction inhibitor in an addition curing silicone composition or a thermally conductive addition curing silicone composition, the pot life or shelf life is less likely to be shortened.

[0013] The present invention also provides an addition-curable silicone composition, which contains an effective amount of the bicyclic acetylenic alcohol compound described above as an addition-curing reaction inhibitor.

[0014] Such an addition-curable silicone composition is an addition-curable silicone composition whose pot life and shelf life are less likely to be shortened.

[0015] The present invention further provides a thermally conductive addition-curable silicone composition, comprising: (A) At least one aliphatic unsaturated hydrocarbon group per molecule, and a kinetic viscosity at 25°C of 60 to 100,000 mm 2 / s: an amount of 1.5 to 89% by mass based on the total composition; (B) at least one thermally conductive filler selected from the group consisting of metals, metal oxides, metal hydroxides, metal nitrides, metal carbides, and allotropes of carbon: an amount of 10 to 98% by mass based on the total mass of the composition; (C) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: an effective amount sufficient for the composition to form a cured product; (D) a platinum group metal catalyst: an effective amount; (E) a bicyclic acetylenic alcohol compound as described above: an effective amount The present invention provides a thermally conductive addition-curable silicone composition comprising:

[0016] Such a thermally conductive addition-curable silicone composition has excellent heat dissipation properties and is less likely to have a shortened pot life or shelf life.

[0017] In this case, the component (B) is preferably silver powder.

[0018] Such a thermally conductive addition-curable silicone composition has superior heat dissipation properties.

[0019] In the present invention, the thermally conductive addition-curable silicone composition further comprises: (F) a phenol compound represented by the following general formula (1A): an amount of 0.01 to 10% by mass based on the total mass of the composition It is preferable that the composition contains the following: [ka] (In general formula (1A), R 1 represents a hydrogen atom, a halogen atom, a cyano group, or a hydroxyl group. Az represents a linear, branched, or cyclic (ka+2)-valent hydrocarbon group having 1 to 20 carbon atoms, or a fluorinated hydrocarbon group, in which -CH2- constituting the hydrocarbon group is -O-, -C(=O)-, or -Si(R 2 R 3)- may be substituted. 2 , R 3 is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group, and -CH2- constituting the alkyl group may be substituted with -O-, -C(=O)-, or -Si(CH3)2-. Each Xf independently represents a hydrogen atom, a halogen atom, a linear, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, an alkoxy group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, or an electron-withdrawing group. Z represents a single bond or an oxygen atom. Each ring ZZ independently represents an aromatic monocyclic or polycyclic ring having 3 to 20 carbon atoms. The carbon atom of the ring ZZ may be substituted with a nitrogen atom, an oxygen atom, or a sulfur atom. ka represents an integer of 0 to 2. kb and kd represent 1 or 2. kc and ke represent integers of 0 to 2.)

[0020] Such a thermally conductive addition-curable silicone composition will more reliably exhibit excellent heat dissipation properties.

[0021] In this case, the component (F) is preferably a phenol compound represented by the following general formula (1B). [ka] (In the general formula (1B), Az' represents a linear, branched, or cyclic hydrocarbon group having 1 to 19 carbon atoms and a valence of (ka'+2), or a fluorinated hydrocarbon group, and -CH2- constituting the hydrocarbon group is -O-, -C(=O)-, or -Si(R 2 R 3 ka' represents 0 or 1. kb', kc', kd', and ke' represent 1 or 2. R 1 , R 2 , R 3 is the same as above.)

[0022] Such a thermally conductive addition-curable silicone composition will more reliably exhibit excellent heat dissipation properties. Effect of the Invention

[0023] As described above, the bicyclic acetylene alcohol compound of the present invention is a tertiary acetylene alcohol compound, and since the α-carbon is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both, it is unlikely to undergo isomerization reaction to α,β-unsaturated ketone. As a result, when it is blended as an addition curing reaction inhibitor in an addition curing silicone composition or a thermally conductive addition curing silicone composition, the pot life and shelf life are unlikely to be shortened. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] As mentioned above, there was a need for the development of bicyclic acetylene alcohol compounds that are less susceptible to isomerization to α,β-unsaturated ketones.

[0025] Means for Solving the Problems The present inventors have conducted intensive research into the above-mentioned problems and have found that the above-mentioned problems can be solved by a tertiary acetylene alcohol compound in which the α-carbon is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both are satisfied, thereby completing the present invention.

[0026] That is, the present invention is a bicyclic acetylene alcohol compound, in which a carbon atom substituted with a hydroxyl group in the compound is a tertiary carbon atom bonded to an acetylene group, and an α-carbon in the compound is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both of these are satisfied.

[0027] The present invention will be described in detail below, but the present invention is not limited thereto. In the following description, some structures represented by chemical formulas may have asymmetric carbons and may have enantiomers or diastereomers, and in such cases, one formula will be used to represent those isomers. Those isomers may be used alone or as a mixture.

[0028] [Bicyclic acetylene alcohol compounds] The present invention is a bicyclic acetylene alcohol compound, in which the carbon atom in the compound substituted with a hydroxyl group is a tertiary carbon atom bonded to an acetylene group, and the α-carbon in the compound is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both are satisfied. Such a compound can be suitably used as an addition curing reaction control agent for addition curing silicone compositions and thermally conductive addition curing silicone compositions.

[0029] In the present invention, the α carbon refers to two carbon atoms other than the acetylene group that are adjacent to the carbon atom substituted with a hydroxyl group.

[0030] This structure makes it difficult for isomerization reactions to occur to form α,β-unsaturated ketones, and therefore the ability to control the addition curing reaction is less likely to decrease, and the pot life and shelf life of the addition curable silicone composition and thermally conductive addition curable silicone composition are less likely to be shortened.

[0031] Specific examples of the bicyclic acetylene alcohol compound include the following: [ka]

[0032] [ka]

[0033] [ka]

[0034] The method for synthesizing the bicyclic acetylene alcohol compound of the present invention is not particularly limited, and the optimum method can be selected depending on the structure. For example, the compound can be obtained by reacting a corresponding bicyclic ketone compound with an ethynylmagnesium halide and treating with an acid, and if necessary, the compound can be purified according to a conventional method such as distillation, recrystallization, or chromatography.

[0035] In addition, the bicyclic acetylene alcohol compound of the present invention preferably has a minimum ring-constituting carbon atom number of 7 or less.

[0036] Cyclic alkenes with seven or fewer members and double bonds in a trans configuration cannot exist stably, and therefore bicyclic acetylene alcohol compounds in which the minimum number of carbon atoms constituting the ring is seven or less are less likely to undergo isomerization reactions to α,β-unsaturated ketones. As a result, the addition curing reaction controllability is less likely to decrease, and the pot life and shelf life of addition curing silicone compositions and thermally conductive addition curing silicone compositions are less likely to be shortened.

[0037] [Addition-curable silicone composition] The addition-curable silicone composition of the present invention contains an effective amount of the bicyclic acetylenic alcohol compound described above as an addition-curing reaction inhibitor.

[0038] There are no particular limitations on the molecular structure or amount of the organopolysiloxane or organohydrogenpolysiloxane having an aliphatic unsaturated hydrocarbon group contained in the addition-curable silicone composition, the presence or absence, type and amount of a filler, the type and amount of a curing catalyst, or the presence or absence of other components, but the bicyclic acetylene alcohol compound of the present invention is particularly effective in terms of its ability to extend the pot life and shelf life of compositions containing acidic components.

[0039] [Thermal conductive addition curing type silicone composition] The thermally conductive addition-curable silicone composition of the present invention contains the bicyclic acetylene alcohol compound described above as component (E), components (A) to (D) described below, and, if necessary, component (F) and / or other components. Each component is described in detail below.

[0040] Component (A) Component (A) has at least one, preferably 1 to 100, and more preferably 2 to 50 aliphatic unsaturated hydrocarbon groups in one molecule, and has a kinetic viscosity at 25°C of 60 to 100,000 mm 2 / s is an organopolysiloxane.

[0041] The aliphatic unsaturated hydrocarbon group is preferably a monovalent hydrocarbon group having an aliphatic unsaturated bond and having 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and further preferably an alkenyl group. Examples of alkenyl groups include vinyl groups, allyl groups, propenyl groups, isopropenyl groups, butenyl groups, hexenyl groups, cyclohexenyl groups, and octenyl groups. Vinyl groups are particularly preferred. The aliphatic unsaturated hydrocarbon group may be bonded to either a silicon atom at the molecular chain terminal or a silicon atom in the molecular chain, or may be bonded to both.

[0042] The organic group other than the aliphatic unsaturated hydrocarbon group bonded to the silicon atom of the organopolysiloxane is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 8 carbon atoms. Examples include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, and decyl groups; aryl groups such as phenyl, tolyl, xylyl, and naphthyl groups; aralkyl groups such as benzyl, phenylethyl, and phenylpropyl groups, 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, or cyano groups, such as chloromethyl, chloropropyl, bromoethyl, trifluoropropyl, and cyanoethyl groups. In particular, methyl and trifluoropropyl groups are preferred.

[0043] The organopolysiloxane has a kinetic viscosity at 25° C. of 60 to 100,000 mm 2 / s, preferably 100 to 30,000 mm 2 / s. The kinetic viscosity is 60 mm 2 / s or more, the physical properties of the thermally conductive addition-curable silicone composition are excellent, and 2 / s or less, the thermally conductive addition-curable silicone composition will have excellent extensibility.

[0044] In the present invention, the kinematic viscosity is a value measured at 25° C. using an Ubbelohde-type Ostwald viscometer (the same applies hereinafter).

[0045] The molecular structure of the organopolysiloxane is not particularly limited as long as it has the above properties, and examples thereof include a linear structure, a branched structure, a partially branched structure, and a linear structure having a cyclic structure. In particular, it is preferable that the main chain is composed of a repeating diorganosiloxane unit and has a linear structure in which both ends of the molecular chain are blocked with triorganosiloxy groups. The organopolysiloxane having the linear structure may have a partially branched structure or a cyclic structure.

[0046] The blending amount of component (A) is preferably 1.5 to 89 mass% of the total composition, more preferably 1.7 to 50 mass%, and even more preferably 2 to 20 mass%. If the blending amount of component (A) is 89 mass% or less, the thermal conductivity will be excellent, and if it is 1.5 mass% or more, the viscosity of the composition will not increase more than necessary, and the workability will be excellent.

[0047] The organopolysiloxanes can be used alone or in combination of two or more.

[0048] (B) Component The component (B) is one or more types of thermally conductive filler selected from the group consisting of metals, metal oxides, metal hydroxides, metal nitrides, metal carbides, and allotropes of carbon. Examples include aluminum, silver, copper, metal silicon, zinc oxide, magnesium oxide, aluminum oxide (alumina), silicon dioxide, cerium oxide, iron oxide, aluminum hydroxide, cerium hydroxide, aluminum nitride, boron nitride, silicon carbide, diamond, graphite, carbon nanotubes, graphene, etc., but silver, particularly silver powder, is preferred because of its excellent thermal conductivity. These can be used alone or in appropriate combination of two or more types, and the ratio is not particularly limited and is arbitrary.

[0049] If the average particle size of component (B) is 0.01 μm or more, the viscosity of the resulting composition will not be too high and the composition will have excellent extensibility, and if it is 300 μm or less, the resulting composition will be uniform, so the range of 0.01 to 300 μm is preferable, more preferably 0.1 to 100 μm, and even more preferably 1 to 50 μm. The average particle size can be determined, for example, as the volume-based average value (or median size) in particle size distribution measurement by laser light diffraction method.

[0050] The component (B) can be used either alone or in combination of two or more kinds, with no particular limitation on the ratio.

[0051] The shape of component (B) is not particularly limited and may be flake-like, spherical, granular, irregular, dendritic, needle-like, etc.

[0052] The blending amount of component (B) is preferably 10 to 98 mass% of the total composition, more preferably 40 to 96 mass%, and even more preferably 70 to 95 mass%. If the blending amount of component (B) is 98 mass% or less, the composition will have excellent extensibility, and if it is 10 mass% or more, the composition will have excellent thermal conductivity.

[0053] (C) Component Component (C) is an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule, i.e., an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms (SiH groups) in one molecule, particularly preferably 2 to 100, and even more preferably 2 to 50. The organohydrogenpolysiloxane may be any organohydrogenpolysiloxane in which the SiH groups in the molecule can undergo an addition reaction with the aliphatic unsaturated hydrocarbon groups in component (A) above in the presence of a platinum group metal catalyst, component (D) described below, to form a crosslinked structure.

[0054] The molecular structure of the organohydrogenpolysiloxane is not particularly limited as long as it has the above-mentioned properties, and examples thereof include a linear structure, a branched structure, a cyclic structure, a partially branched structure, and a linear structure having a cyclic structure, etc. A linear structure or a cyclic structure is preferred.

[0055] The organohydrogenpolysiloxane preferably has a kinetic viscosity at 25° C. of 1 to 1,000 mm 2 / s, more preferably 10 to 300 mm 2 / s. The kinetic viscosity is 1 mm 2 / s or more, the physical properties of the thermally conductive addition-curable silicone composition are excellent. 2 If this is the case, the thermally conductive addition-curable silicone composition will have good extensibility.

[0056] The organic group bonded to the silicon atom of the organohydrogenpolysiloxane may be an unsubstituted or substituted monovalent hydrocarbon group other than an aliphatic unsaturated hydrocarbon group. In particular, it is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms. For example, it may be an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, or a dodecyl group, an aryl group such as a phenyl group, an aralkyl group such as a 2-phenylethyl group or a 2-phenylpropyl group, or a group in which some or all of the hydrogen atoms of these groups are substituted with a halogen atom such as a fluorine atom, a bromine atom, or a chlorine atom, a cyano group, or an epoxy ring-containing organic group (a glycidyl group or a glycidyloxy group-substituted alkyl group), such as a chloromethyl group, a chloropropyl group, a bromoethyl group, a trifluoropropyl group, a cyanoethyl group, a 2-glycidoxyethyl group, a 3-glycidoxypropyl group, or a 4-glycidoxybutyl group. Among these, a methyl group or a trifluoropropyl group is preferable.

[0057] The organohydrogenpolysiloxanes may be used alone or in combination of two or more.

[0058] The amount of organohydrogenpolysiloxane (C) is an effective amount sufficient for the composition to form a cured product, and is preferably an amount such that the number of SiH groups in (C) relative to the total number of aliphatic unsaturated hydrocarbon groups in (A) is 0.5 to 10, more preferably 0.7 to 7.5, and even more preferably 1.0 to 5.0. If the amount of (C) is equal to or greater than the lower limit, the addition reaction proceeds sufficiently and crosslinking is sufficient. If the amount is equal to or less than the upper limit, the crosslinked structure is uniform and the composition has good storage stability.

[0059] (D) Component Component (D) is a platinum group metal catalyst, which functions to promote the addition curing reaction of the above-mentioned components. The platinum group metal catalyst may be any of those conventionally known for addition curing reactions. Examples include platinum-based, palladium-based, and rhodium-based catalysts, among which platinum or platinum compounds, which are relatively easy to obtain, are preferred. Examples include platinum alone, platinum black, chloroplatinic acid, platinum-olefin complexes, platinum-alcohol complexes, and platinum coordination compounds. The platinum group metal catalyst may be used alone or in combination of two or more.

[0060] The amount of component (D) to be blended should be an effective amount as a catalyst, that is, an effective amount required to accelerate the addition curing reaction and cure the heat-conductive addition curing silicone composition of the present invention. The amount is preferably 0.1 to 500 ppm, more preferably 0.5 to 300 ppm, and even more preferably 1 to 200 ppm, calculated as platinum group metal atoms, based on the mass of the entire composition. If the amount of component (D) is equal to or greater than the lower limit, the catalytic effect is obtained, and if it is equal to or less than the upper limit, the catalytic effect is sufficient and economical.

[0061] (E) Component The thermally conductive addition-curable silicone composition of the present invention contains the above-described bicyclic acetylene alcohol compound as component (E) as an addition-curing reaction inhibitor.

[0062] The amount of component (E) blended may be an effective amount, and is preferably 0.05 to 10 parts by mass, more preferably 0.07 to 5 parts by mass, and even more preferably 0.1 to 2 parts by mass, per 100 parts by mass of component (A). When the amount of component (E) blended is 0.05 parts by mass or more, the desired sufficient shelf life and pot life are obtained, and when it is 10 parts by mass or less, the curability of the silicone composition is sufficient.

[0063] The bicyclic acetylene alcohol compounds of the component (E) may be used either individually or in combination of two or more.

[0064] Furthermore, component (E) may be diluted with an organo(poly)siloxane, toluene, or the like to improve dispersibility in the thermally conductive addition-curable silicone composition.

[0065] In addition to the components described above, the following optional components may also be added to the thermally conductive addition-curable silicone composition of the present invention, as necessary.

[0066] Ingredient (F) Component (F) is a phenolic compound that is blended as an additive to the thermally conductive addition curable silicone composition. The phenolic compound is preferably a phenolic compound represented by the following general formula (1A). In the following explanation, some structures represented by chemical formulas may have asymmetric carbons and may have enantiomers or diastereomers, in which case a single formula will be used to represent those isomers. Those isomers may be used alone or as a mixture. [ka] (In general formula (1A), R 1 represents a hydrogen atom, a halogen atom, a cyano group, or a hydroxyl group. Az represents a linear, branched, or cyclic (ka+2)-valent hydrocarbon group having 1 to 20 carbon atoms, or a fluorinated hydrocarbon group, in which -CH2- constituting the hydrocarbon group is -O-, -C(=O)-, or -Si(R 2 R 3 )- may be substituted. 2 , R 3is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group, and -CH2- constituting the alkyl group may be substituted with -O-, -C(=O)-, or -Si(CH3)2-. Each Xf independently represents a hydrogen atom, a halogen atom, a linear, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, an alkoxy group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, or an electron-withdrawing group. Z represents a single bond or an oxygen atom. Each ring ZZ independently represents an aromatic monocyclic or polycyclic ring having 3 to 20 carbon atoms. The carbon atom of the ring ZZ may be substituted with a nitrogen atom, an oxygen atom, or a sulfur atom. ka represents an integer of 0 to 2. kb and kd represent 1 or 2. kc and ke represent integers of 0 to 2.)

[0067] Specific examples of Az which is a linear, branched or cyclic (ka+2)-valent hydrocarbon group having 1 to 20 carbon atoms include the following. [ka] (In the formula, the dashed lines represent bonds.)

[0068] [ka] (In the formula, the dashed lines represent bonds.)

[0069] [ka] (In the formula, the dashed lines represent bonds.)

[0070] Specific examples of the linear, branched or cyclic (ka+2)-valent fluorinated hydrocarbon group having 1 to 20 carbon atoms for Az include the above-mentioned hydrocarbon groups in which some or all of the hydrogen atoms have been substituted with fluorine atoms. In addition, -CH2- constituting the hydrocarbon group may be -O-, -C(=O)-, or -Si(R 2 R 3The number of carbon atoms in Az is preferably 2 to 18, more preferably 3 to 16, and further preferably 4 to 14. In addition, a part of -CH2- constituting the hydrocarbon group may be replaced by -Si(R 2 R 3 )- or -Si(R 2 R 3 )-O- is preferably substituted.

[0071] R 2 , R 3 Specific examples of the linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.

[0072] Specific examples of the halogen atom of Xf include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0073] Specific examples of the linear, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom for Xf include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a cyclopropyl group, and a cyclobutyl group, a trifluoromethyl group, and a 2,2,2-trifluoroethyl group.

[0074] Specific examples of the alkoxy group having 1 to 10 carbon atoms which may be substituted with a fluorine atom for Xf include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, a cyclopropoxy group, a trifluoromethoxy group, and a 2,2,2-trifluoroethoxy group.

[0075] Specific examples of the electron-withdrawing group of Xf include a carbonyl group, an alkoxycarbonyl group, a cyano group, a nitro group, a sulfo group, a formyl group, a sulfonate ester group, an amide group, -OC(=O)-G- (G is a sulfur atom or NH), and the like.

[0076] Specific examples of the aromatic monocyclic or polycyclic ring having 3 to 20 carbon atoms for the ring ZZ include the following: The ring ZZ may further have a substituent as shown below. [ka]

[0077] It is particularly preferable that the component (F) is a phenol compound represented by the following general formula (1B). [ka] (In the general formula (1B), Az' represents a linear, branched, or cyclic hydrocarbon group having 1 to 19 carbon atoms and a valence of (ka'+2), or a fluorinated hydrocarbon group, and -CH2- constituting the hydrocarbon group is -O-, -C(=O)-, or -Si(R 2 R 3 ka' represents 0 or 1. kb', kc', kd', and ke' represent 1 or 2. R 1 , R 2 , R 3 is the same as above.)

[0078] Specific examples of the phenol compounds represented by the above general formulas (1A) and (1B) include the following. [ka]

[0079] [ka]

[0080] [ka]

[0081] [ka]

[0082] [ka]

[0083] [ka]

[0084] [ka]

[0085] The blend amount of component (F) is preferably 0.01 to 10 mass% of the total composition, more preferably 0.03 to 5 mass%, and even more preferably 0.05 to 1.0 mass%. When the blend amount of component (F) is 0.01 mass% or more, it has the effect of contributing to improving the heat dissipation properties of the thermally conductive addition curable silicone composition, and when it is 10 mass% or less, the effect of improving heat dissipation is sufficient and it is economical.

[0086] Other Ingredients The thermally conductive addition curable silicone composition of the present invention may contain a non-reactive organo(poly)siloxane such as methylpolysiloxane in order to adjust the strength and viscosity of the composition. Furthermore, for the purpose of improving the filling property of the thermally conductive filler or for the purpose of imparting adhesiveness to the composition, a hydrolyzable organopolysiloxane, various modified silicones, or a hydrolyzable organosilane may be blended. Furthermore, a solvent may be blended to adjust the viscosity of the composition. Furthermore, in order to prevent deterioration of the thermally conductive addition curable silicone composition, a conventionally known antioxidant such as 2,6-di-tert-butyl-4-methylphenol may be included as necessary. Furthermore, a dye, a pigment, a flame retardant, a settling inhibitor, or a thixotropy improver may be blended as necessary.

[0087] Method for producing thermally conductive addition-curable silicone composition The method for producing the thermally conductive addition-curable silicone composition of the present invention is not particularly limited, but includes the step of producing a thermally conductive addition-curable silicone composition containing the above-mentioned components (A) to (E) and, if necessary, component (F) and / or other components.

[0088] The above-mentioned components (A) to (E), and optionally component (F) and other components, are mixed at 25° C. for usually 3 minutes to 24 hours, preferably 5 minutes to 12 hours, and particularly preferably 10 minutes to 6 hours, using a mixer such as Trimix, Twinmix, Planetary Mixer (all registered trademarks of mixers manufactured by Inoue Seisakusho Co., Ltd.), Ultramixer (registered trademark of mixers manufactured by Mizuho Kogyo Co., Ltd.), or Hivismix (registered trademark of mixers manufactured by Primix Corporation). Degassing may be performed during mixing, and mixing may be performed while heating at a temperature in the range of 40 to 170° C.

[0089] In the present invention, from the viewpoint of enabling the thermally conductive addition-curable silicone composition to exhibit good thermal conductivity, it is preferable to first mix components (A) and (B) at 70° C., and then mix components (C), (D), and (E) at 25° C. When the optional component (F) is added, it is preferable to first mix components (A) and (B), then mix component (F), and then mix components (C), (D), and (E).

[0090] The thermally conductive addition curable silicone composition of the present invention has a viscosity measured at 25°C of preferably 10 to 1,000 Pa·s, more preferably 20 to 700 Pa·s, and even more preferably 40 to 600 Pa·s. If the viscosity is 10 Pa·s or more, the shape is easily maintained and the thermally conductive filler does not settle, resulting in good workability. If the viscosity is 1,000 Pa·s or less, the workability is good, such as easy discharge and application. The above-mentioned viscosity can be obtained by adjusting the blending amount of each of the above-mentioned components. The above-mentioned viscosity can be measured at 25°C, for example, using a Malcom viscometer (type PC-1T).

[0091] Furthermore, the cured product of the thermally conductive addition-curable silicone composition of the present invention typically has a thermal conductivity of 0.5 to 100 W / m·K. The thermal conductivity can be calculated, for example, from the following formula. (Thickness of silicone composition [μm]) ÷ (Thermal resistance value of silicone composition [mm 2 K / W] The thermal resistance value can be measured, for example, using Nanoflash (manufactured by Nitsche, LFA447).

[0092] The curing conditions when heat curing the thermally conductive addition curable silicone composition of the present invention are not particularly limited, but are typically 80 to 200°C, preferably 100 to 180°C, for 15 minutes to 4 hours, preferably 30 minutes to 2 hours. EXAMPLES

[0093] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples. The structural analysis of the compounds was performed using a BRUKER nuclear magnetic resonance apparatus AVANCEIII HD NanoBay 400MHz and a PerkinElmer Fourier transform infrared spectrometer Spectrum One.

[0094] The bicyclic acetylene alcohol compounds 1 to 3 of the present invention were synthesized by the following method.

[0095] [Synthesis Example 1] Synthesis of bicyclic acetylenic alcohol compound 1 [ka] Under a nitrogen atmosphere, bicyclo[3.3.1]nonan-9-one (0.69 g) was dissolved in THF (5.0 ml) and cooled to 0°C. 0.5 M ethynylmagnesium bromide THF solution (15.0 ml) was carefully added dropwise at an internal temperature of 10°C or less. The mixture was then stirred at room temperature for 24 hours. 0.5 N aqueous hydrochloric acid (20.0 ml) was then added and stirred at room temperature for 10 minutes. The aqueous layer after separation of the organic layer was extracted three times with ethyl acetate (40 ml), and the organic layer was combined and neutralized and washed with tap water. Dehydrated sodium sulfate (40 g) was added to the organic layer after neutralization and washing, and the mixture was stirred at room temperature for 3 hours. The sodium sulfate was filtered off and then concentrated to obtain bicyclic acetylene alcohol compound 1 (0.70 g, yield 85%) as a light brown solid. 1 H-NMR (400MHz in DMSO-d6): δ = 5.24 (1H, s), 3.25 (1H, s), 2.10~1.32 (14H, m) ppm.

[0096] [Synthesis Example 2] Synthesis of bicyclic acetylenic alcohol compound 2 [ka] Under a nitrogen atmosphere, 3-methylene-2-norbornanone (2.44 g) was dissolved in THF (20 ml) and cooled to 0°C. 0.5 M ethynylmagnesium bromide THF solution (60.0 ml) was carefully added dropwise at an internal temperature of 10°C or less. The mixture was then stirred at room temperature for 24 hours. 0.5 N aqueous hydrochloric acid (80.0 ml) was then added and stirred at room temperature for 10 minutes. The aqueous layer after separation of the organic layer was extracted three times with ethyl acetate (120 ml), and the organic layer was combined and neutralized and washed with tap water. Dehydrated sodium sulfate (140 g) was added to the organic layer after neutralization and washing, and the mixture was stirred at room temperature for 3 hours. The sodium sulfate was filtered off and then concentrated to obtain bicyclic acetylene alcohol compound 2 (2.48 g, 84% yield) as an orange-brown transparent liquid. 1 H-NMR (400MHz in DMSO-d6): δ = 5.63 (1H, s), 4.96 (1H, s), 4.85 (1H, s), 3.20 (1H, s), 2.67 (1H, s), 2.31 (1H, s), 1.87~1.27 (8H, m)ppm.

[0097] [Synthesis Example 3] Synthesis of bicyclic acetylenic alcohol compound 3 [ka] Under a nitrogen atmosphere, (+)-fenchone (2.28 g) was dissolved in THF (15 ml) and cooled to 0°C. 0.5 M ethynylmagnesium bromide THF solution (45.0 ml) was carefully added dropwise at an internal temperature of 10°C or less. The mixture was then stirred at 50°C for 7 hours. 0.5 N aqueous hydrochloric acid (60.0 ml) was then added and stirred at room temperature for 10 minutes. The aqueous layer after separating the organic layer was extracted three times with ethyl acetate (80 ml), and the organic layer was combined and neutralized with tap water and washed. Dehydrated sodium sulfate (70 g) was added to the organic layer after neutralization and washing, and the mixture was stirred at room temperature for 3 hours. The sodium sulfate was filtered off and then concentrated to obtain bicyclic acetylene alcohol compound 3 (2.04 g, 76% yield) as a pale orange transparent liquid. 1 H-NMR (400MHz in DMSO-d6): δ = 5.01 (1H, s), 3.26 (1H, s), 2.11 (1H, s), 1.89~0.85 (16H, m) ppm.

[0098] The following components were prepared to prepare the thermally conductive addition-curable silicone composition of the present invention. The kinetic viscosity was measured at 25°C using an Ubbelohde-type Ostwald viscometer.

[0099] Component (A) A-1: Both ends are blocked with dimethylvinylsilyl groups, and the kinetic viscosity at 25°C is 600mm 2 / s dimethylpolysiloxane (SiVi=0.014mol / 100g)

[0100] (B) Component B-1: Average particle size 2μm, tap density 2.4g / mL, specific surface area 0.9m 2 / g flake silver powder B-2: Average particle size 3μm, tap density 7.0g / mL, specific surface area 0.2m 2 / g spherical silver powder

[0101] (C) Component C-1: Methylhydrogendimethylpolysiloxane represented by the following formula (2): (Kinematic viscosity at 25°C = 100mm 2 / s, SiH = 0.0055 mol / g) [ka]

[0102] (D) Component D-1: A solution of platinum-divinyltetramethyldisiloxane complex dissolved in the same dimethylpolysiloxane as A-1 (platinum atom content: 1% by mass)

[0103] (E) Component E-1: Bicyclic acetylene alcohol compound 1 synthesized in Synthesis Example 1 and represented by the following formula (3) [ka] E-2: A solution in which the bicyclic acetylene alcohol compound 1 synthesized in Synthesis Example 1 represented by the above formula (3) was dissolved in toluene (bicyclic acetylene alcohol compound 1 content: 50% by mass) E-3: Bicyclic acetylene alcohol compound 2 synthesized in Synthesis Example 2 and represented by the following formula (4) [ka] e-4 (for comparison): An acetylene alcohol compound represented by the following formula (5) [ka] e-5 (for comparison): An acetylene alcohol compound represented by the following formula (6) [ka]

[0104] Ingredient (F) F-1: A phenol compound represented by the following formula (7): [ka]

[0105] [Examples 1 to 3, Comparative Examples 1 to 3] Preparation of Thermally Conductive Addition-Cure Silicone Compositions Thermally conductive addition-curable silicone compositions were prepared by blending the above components (A) to (F) in the amounts and by the methods shown below in Tables 1 and 2. In the tables, SiH / SiVi is the ratio of the total number of SiH groups in component (C) to the total number of alkenyl groups in component (A). Components (A) and (B) were added to 0.3 liters of Hibismix (manufactured by Primix Corporation) and mixed for 1 hour at 70° C. After cooling to 40° C. or below, components (F), (E), (D), and (C) were added and mixed uniformly to prepare a thermally conductive addition-curable silicone composition. For each of the thermally conductive addition-curable silicone compositions obtained by the above method, the viscosity, thermal conductivity, and pot life at 25° C. were measured according to the following methods. The results are shown in Tables 1 and 2.

[0106] [viscosity] The absolute viscosity of each thermally conductive addition-curable silicone composition was measured at 25° C. using a Malcolm viscometer (Type PC-1T) (rotor A, 10 rpm, shear rate 6 [1 / s]).

[0107] [Thermal Conductivity] Each heat-conductive addition-curing silicone composition was sandwiched between two silicon plates with a diameter of 12.7 mm, and heat-cured at 125°C for 1 hour under a pressure of 0.14 MPa to prepare a test piece for measuring heat resistance, and measure the heat resistance value of the heat-conductive addition-curing silicone cured product.Furthermore, the thickness of the test piece was measured with a micro gauge, and the thickness of the heat-conductive addition-curing silicone cured product was calculated from the difference with the thickness of the silicon plate that had been measured in advance.Then, the thermal conductivity of the heat-conductive addition-curing silicone cured product was derived from the following formula. (Thickness of the thermally conductive addition-cured silicone, μm) ÷ (Thermal resistance of the thermally conductive addition-cured silicone, mm 2 K / W) For the thermal resistance measurement, Nanoflash (manufactured by Nitsche, LFA447) was used.

[0108] [25℃ pot life] The absolute viscosity of each thermally conductive addition-curable silicone composition was measured at 25°C using a Malcolm viscometer (Type PC-1T) (rotor A, 10 rpm, shear rate 6 [1 / s]), and then the absolute viscosity after storing at 25°C for 24 hours was measured in the same manner, and the difference in viscosity before and after was calculated.

[0109] [Table 1]

[0110] [Table 2]

[0111] The results in Table 1 show that the thermally conductive addition-curable silicone compositions of Examples 1 to 3, which contain a bicyclic acetylene alcohol compound of the present invention as an addition-curing reaction inhibitor, have a small difference between the initial viscosity and the viscosity after storage at 25°C for 24 hours.

[0112] On the other hand, the results in Table 2 show that the thermally conductive addition-curable silicone compositions of Comparative Examples 1 to 3, which do not contain the bicyclic acetylene alcohol compound of the present invention as an addition-curing reaction inhibitor, have a large difference between the initial viscosity and the viscosity after storage at 25°C for 24 hours.

[0113] In other words, it is clear that the pot life at 25°C of a thermally conductive addition-curable silicone composition that contains a bicyclic acetylene alcohol compound of the present invention as an addition-curing reaction inhibitor is extended.

[0114] The present specification includes the following aspects. [1]: A bicyclic acetylene alcohol compound, characterized in that a carbon atom in the compound substituted with a hydroxyl group is a tertiary carbon atom bonded to an acetylene group, and an α-carbon in the compound is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both. [2]: The bicyclic acetylene alcohol compound according to [1] above, characterized in that the minimum number of carbon atoms constituting the ring is 7 or less. [3]: An addition-curable silicone composition, comprising an effective amount of the bicyclic acetylene alcohol compound of [1] or [2] above as an addition-curing reaction inhibitor. [4]: A thermally conductive addition-curable silicone composition, (A) At least one aliphatic unsaturated hydrocarbon group per molecule, and a kinetic viscosity at 25°C of 60 to 100,000 mm 2 / s: an amount of 1.5 to 89% by mass based on the total composition; (B) at least one thermally conductive filler selected from the group consisting of metals, metal oxides, metal hydroxides, metal nitrides, metal carbides, and allotropes of carbon: an amount of 10 to 98% by mass based on the total mass of the composition; (C) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: an effective amount sufficient for the composition to form a cured product; (D) a platinum group metal catalyst: an effective amount; (E) The bicyclic acetylene alcohol compound of the above [1] or [2]: an effective amount 1. A thermally conductive addition-curable silicone composition comprising: [5]: The thermally conductive addition-curable silicone composition according to [4] above, wherein the component (B) is silver powder. [6]: The thermally conductive addition-curable silicone composition further comprises: (F) a phenol compound represented by the following general formula (1A): an amount of 0.01 to 10% by mass based on the total mass of the composition The thermally conductive addition-curable silicone composition according to the above item [4] or [5], comprising: [ka] (In general formula (1A), R 1 represents a hydrogen atom, a halogen atom, a cyano group, or a hydroxyl group. Az represents a linear, branched, or cyclic (ka+2)-valent hydrocarbon group having 1 to 20 carbon atoms, or a fluorinated hydrocarbon group, in which -CH2- constituting the hydrocarbon group is -O-, -C(=O)-, or -Si(R 2 R 3 )- may be substituted. 2 , R 3is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group, and -CH2- constituting the alkyl group may be substituted with -O-, -C(=O)-, or -Si(CH3)2-. Each Xf independently represents a hydrogen atom, a halogen atom, a linear, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, an alkoxy group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, or an electron-withdrawing group. Z represents a single bond or an oxygen atom. Each ring ZZ independently represents an aromatic monocyclic or polycyclic ring having 3 to 20 carbon atoms. The carbon atom of the ring ZZ may be substituted with a nitrogen atom, an oxygen atom, or a sulfur atom. ka represents an integer of 0 to 2. kb and kd represent 1 or 2. kc and ke represent integers of 0 to 2.) [7]: The thermally conductive addition-curable silicone composition according to [6] above, wherein the component (F) is a phenol compound represented by the following general formula (1B): [ka] (In the general formula (1B), Az' represents a linear, branched, or cyclic hydrocarbon group having 1 to 19 carbon atoms and a valence of (ka'+2), or a fluorinated hydrocarbon group, and -CH2- constituting the hydrocarbon group is -O-, -C(=O)-, or -Si(R 2 R 3 ka' represents 0 or 1. kb', kc', kd', and ke' represent 1 or 2. R 1 , R 2 , R 3 is the same as above.)

[0115] The present invention is not limited to the above-described embodiment. The above-described embodiment is merely an example, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included in the technical scope of the present invention.

Claims

1. A bicyclic acetylene alcohol compound, characterized in that a carbon atom in the compound substituted with a hydroxyl group is a tertiary carbon atom bonded to an acetylene group, and an α-carbon in the compound is a bridgehead carbon, or there is no hydrogen atom on the α-carbon, or both of these are satisfied.

2. 2. The bicyclic acetylene alcohol compound according to claim 1, characterized in that the minimum number of carbon atoms constituting the ring is 7 or less.

3. 3. An addition-curable silicone composition comprising an effective amount of the bicyclic acetylene alcohol compound according to claim 1 or 2 as an addition-curing reaction inhibitor.

4. A thermally conductive addition-curable silicone composition comprising: (A) A copolymer having at least one aliphatic unsaturated hydrocarbon group per molecule and a kinetic viscosity at 25°C of 60 to 100,000 mm ２ / s: an amount of 1.5 to 89 mass% based on the total composition; (B) at least one thermally conductive filler selected from the group consisting of metals, metal oxides, metal hydroxides, metal nitrides, metal carbides, and allotropes of carbon: in an amount of 10 to 98% by mass based on the total mass of the composition; (C) an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: an effective amount sufficient for the composition to form a cured product; (D) a platinum group metal catalyst: an effective amount, (E) The bicyclic acetylene alcohol compound according to claim 1 or 2: an effective amount 1. A thermally conductive addition-curable silicone composition comprising:

5. 5. The thermally conductive addition-curable silicone composition according to claim 4, wherein the component (B) is silver powder.

6. The thermally conductive addition-curable silicone composition further comprises: (F) a phenol compound represented by the following general formula (1A): an amount of 0.01 to 10% by mass based on the total mass of the composition 5. The thermally conductive addition-curable silicone composition according to claim 4, comprising: 【Chemistry 1】 (In general formula (1A), R １ represents a hydrogen atom, a halogen atom, a cyano group, or a hydroxyl group. Az represents a linear, branched, or cyclic (ka+2)-valent hydrocarbon group having 1 to 20 carbon atoms, or a fluorinated hydrocarbon group, and the -CH ２ - is -O-, -C(=O)-, or -Si(R ２ R ３ )- may be substituted. ２ , R ３ is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group, and the --CH ２ - is -O-, -C(=O)-, or -Si(CH ３ ) ２ - may be substituted. Each Xf independently represents a hydrogen atom, a halogen atom, a linear, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, an alkoxy group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, or an electron-withdrawing group. Z represents a single bond or an oxygen atom. Each ring ZZ independently represents an aromatic monocyclic or polycyclic ring having 3 to 20 carbon atoms. The carbon atom of the ring ZZ may be substituted with a nitrogen atom, an oxygen atom, or a sulfur atom. ka represents an integer of 0 to 2. kb and kd represent 1 or 2. kc and ke represent integers of 0 to 2.)

7. 7. The thermally conductive addition-curable silicone composition according to claim 6, wherein the component (F) is a phenol compound represented by the following general formula (1B): 【Chemistry 2】 In the general formula (1B), Az' represents a linear, branched, or cyclic hydrocarbon group having 1 to 19 carbon atoms and a valence of (ka'+2), or a fluorinated hydrocarbon group, and -CH ２ - is -O-, -C(=O)-, or -Si(R ２ R ３ ka' represents 0 or 1. kb', kc', kd', and ke' represent 1 or 2. R １ , R ２ , R ３ is the same as above.)

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