Two-component curing polyurethane resin composition

Abstract

Provided is a two-component curable polyurethane resin composition that exhibits excellent thermal conductivity and adhesiveness while suppressing an increase in the viscosity of the first component containing a polyol. [Solution] The two-component curing polyurethane resin composition according to one embodiment comprises a first component containing a polyol (A) and a heat-dissipating filler (C1), and a second component containing a polyisocyanate (B) and a heat-dissipating filler (C2), wherein the polyol (A) contains 50 to 100 mass% of a non-crystalline alkanediol (a1) relative to 100 mass% of the polyol (A), the polyisocyanate (B) contains an aliphatic polyisocyanate (b1), the content of the heat-dissipating filler (C1) is 45 to 90 mass% relative to 100 mass% of the first component, and the content of the heat-dissipating filler (C2) is 45 to 90 mass% relative to 100 mass% of the second component.

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a two-component curable polyurethane resin composition and a heat dissipation material using the same. [Background technology]

[0002] Polyurethane resin compositions are used, for example, as heat-dissipating materials in electric or electronic devices. For example, Patent Document 1 describes a two-component polyurethane resin composition containing a base part containing a polyol compound and a filler, and a curing agent part containing a polyisocyanate and a filler. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2024-513527 Summary of the Invention [Problem to be solved by the invention]

[0004] A heat-dissipating material is sometimes disposed between a heat-generating component and a cooling component, and the heat-generating component and the cooling component are bonded together via the heat-dissipating material. In this case, if the adhesiveness of the heat-dissipating material to the heat-generating component and the cooling component is low, the heat generated in the heat-generating component is less likely to be transferred to the cooling component, resulting in reduced cooling efficiency. Similarly, if the thermal conductivity of the heat-dissipating material is low, the cooling efficiency is also reduced. Therefore, when a polyurethane resin composition is used as a heat-dissipating material, it is desirable that the polyurethane resin composition have excellent adhesive properties to the heat-generating component and the cooling component, as well as high thermal conductivity. However, adding a large amount of inorganic filler to improve thermal conductivity tends to reduce adhesiveness and increase viscosity. Thus, it is difficult to achieve high thermal conductivity, adhesiveness, and low viscosity at the same time.

[0005] In view of the above, an object of an embodiment of the present invention is to provide a two-component curable polyurethane resin composition that exhibits excellent thermal conductivity and adhesiveness while suppressing an increase in the viscosity of the first component containing a polyol. [Means for solving the problem]

[0006] The present invention includes the embodiments shown below. [1] A two-component curable polyurethane resin composition comprising a first component containing a polyol (A) and a heat-dissipating filler (C1), and a second component containing a polyisocyanate (B) and a heat-dissipating filler (C2), the polyol (A) contains 50 to 100 mass% of a non-crystalline alkanediol (a1) based on 100 mass% of the polyol (A), The polyisocyanate (B) includes an aliphatic polyisocyanate (b1), the content of the heat-dissipating filler (C1) is 45 to 90% by mass relative to 100% by mass of the first component, The content of the heat-dissipating filler (C2) is 45 to 90% by mass relative to 100% by mass of the second component. A two-component curing polyurethane resin composition. [2] The two-component curable polyurethane resin composition according to [1], wherein the amorphous alkanediol (a1) has 6 or more and 9 or less carbon atoms. [3] The two-component curing polyurethane resin composition according to [1] or [2], wherein the amorphous alkanediol (a1) comprises at least one selected from the group consisting of 2-ethyl-1,3-hexanediol, 2,4-diethyl-1,5-pentanediol, and 3-methyl-1,5-pentanediol. [4] The two-component curing polyurethane resin composition according to any one of [1] to [3], wherein the polyol (A) further comprises at least one selected from the group consisting of castor oil-based polyols, polyether polyols, and polyester polyols. [5] The two-component curing polyurethane resin composition according to any one of [1] to [4], wherein the polyisocyanate (B) contains the aliphatic polyisocyanate (b1) in an amount of 70 to 100% by mass based on 100% by mass of the polyisocyanate (B). [6] The two-component curable polyurethane resin composition according to any one of [1] to [5], wherein the heat-dissipating filler (C1) and the heat-dissipating filler (C2) are surface-treated with a silane coupling agent. [7] The two-component curing polyurethane resin composition according to any one of [1] to [6], wherein the mass ratio of the second component to the first component (second component / first component) is 50 / 100 to 500 / 100. [8] A heat dissipating material comprising the two-component curing polyurethane resin composition according to any one of [1] to [7]. [Effects of the Invention]

[0007] According to an embodiment of the present invention, it is possible to provide a two-component curable polyurethane resin composition that exhibits excellent thermal conductivity and adhesiveness while suppressing an increase in the viscosity of the first component containing a polyol. DETAILED DESCRIPTION OF THE INVENTION

[0008] The two-component curing polyurethane resin composition according to this embodiment comprises a first component containing a polyol (A) and a thermally conductive filler (C1), and a second component containing a polyisocyanate (B) and a thermally conductive filler (C2). The polyol (A) contains 50 to 100 mass% of a non-crystalline alkanediol (a1) relative to 100 mass% of the polyol (A). The polyisocyanate (B) contains an aliphatic polyisocyanate (b1). The thermally conductive filler (C1) is contained in an amount of 45 to 90 mass% relative to 100 mass% of the first component, and the thermally conductive filler (C2) is contained in an amount of 45 to 90 mass% relative to 100 mass% of the second component. The first and second components are liquid, i.e., fluid, at room temperature (25°C).

[0009] <First component> [Polyol (A)] The first component contains a polyol (A). The content of the polyol (A) may be, for example, 10 to 55 mass%, 10 to 50 mass%, 10 to 30 mass%, or 10 to 20 mass% relative to 100 mass% of the first component.

[0010] [Amorphous alkanediol (a1)] The polyol (A) contains a non-crystalline alkanediol (a1). The non-crystalline alkanediol (a1) is an alkanediol that is liquid at room temperature (25°C), i.e., has fluidity. An alkanediol is a compound in which two hydrogen atoms of a chain saturated hydrocarbon are substituted with hydroxyl groups. By including the non-crystalline alkanediol (a1) in the first component, it is possible to improve thermal conductivity and adhesiveness while suppressing an increase in the viscosity of the first component containing the polyol.

[0011] Examples of the amorphous alkanediol (a1) include 2-ethyl-1,3-hexanediol, 2,4-diethyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, and 2-methyloctane-1,8-diol.

[0012] In this embodiment, the amorphous alkanediol (a1) is contained in an amount of 50 to 100% by mass relative to 100% by mass of the polyol (A). The content of the amorphous alkanediol (a1) is preferably 60 to 95% by mass, more preferably 65 to 90% by mass, and even more preferably 70 to 90% by mass relative to 100% by mass of the polyol (A).

[0013] In one embodiment, the number of carbon atoms in the amorphous alkanediol (a1) is preferably 6 or more and 9 or less, more preferably 8. In addition, the amorphous alkanediol (a1) is preferably a branched alkanediol.

[0014] In one embodiment, the amorphous alkanediol (a1) preferably contains at least one selected from the group consisting of 2-ethyl-1,3-hexanediol, 2,4-diethyl-1,5-pentanediol, and 3-methyl-1,5-pentanediol. In this case, the total content of 2-ethyl-1,3-hexanediol, 2,4-diethyl-1,5-pentanediol, and 3-methyl-1,5-pentanediol may be, for example, 70 to 100 mass%, 80 to 100 mass%, or 90 to 100 mass%, relative to 100 mass% of the amorphous alkanediol (a1).

[0015] [Polyol other than amorphous alkanediol (a1)] The polyol (A) may further contain a polyol other than the amorphous alkanediol (a1). Examples of polyols other than the amorphous alkanediol (a1) include polyether polyols, polyester polyols, polycarbonate polyols, acrylic polyols, castor oil-based polyols, polyolefin polyols, aliphatic polyols, and aromatic polyols. Examples of the castor oil-based polyols include castor oil, castor oil fatty acids, and polyols produced using hydrogenated castor oils and hydrogenated castor oil fatty acids. More specifically, examples of the castor oil-based polyols include castor oil, transesterification products of castor oil and other natural fats and oils, reaction products of castor oil and polyhydric alcohols, esterification products of castor oil fatty acids and polyhydric alcohols, and polyols obtained by addition polymerization of these with alkylene oxides.

[0016] The number of functional groups (number of hydroxyl groups) of the polyol other than the amorphous alkanediol (a1) is not particularly limited, and for example, any one of those having 2 to 5 functional groups may be used, or two or more types having different numbers of functional groups may be used in combination. Preferably, one having 2 to 3 functional groups is used.

[0017] The hydroxyl value of the polyol other than the amorphous alkanediol (a1) is not particularly limited, and for example, one of those having a hydroxyl value of 50 to 450 mgKOH / g may be used alone, or two or more of them may be used in combination. Preferably, one having a hydroxyl value of 100 to 300 mgKOH / g is used. Here, the hydroxyl value of the polyol is measured in accordance with Method A of JIS K1557-1:2007.

[0018] In one embodiment, the polyol (A) preferably contains at least one polyol selected from the group consisting of castor oil-based polyols, polyether polyols, and polyester polyols (hereinafter referred to as "polyol (a2)") as a polyol other than the amorphous alkanediol (a1). Among these, it is more preferable that the polyol (A) contains a castor oil-based polyol. The content of the polyol (a2) (preferably the content of the castor oil-based polyol) in 100% by mass of the polyol (A) is preferably 50% by mass or less, more preferably 5 to 40% by mass, even more preferably 10 to 35% by mass, and particularly preferably 10 to 30% by mass.

[0019] [Thermal dissipation filler (C1)] The first component contains a heat-dissipating filler (C1). The inclusion of the heat-dissipating filler (C1) in the first component improves thermal conductivity. Examples of the heat-dissipating filler (C1) include metal hydroxides, metal oxides, and metal nitrides, which may be used alone or in combination of two or more. The heat-dissipating filler (C1) may be a mixture of two or more types of heat-dissipating fillers with different average particle sizes.

[0020] Examples of metal hydroxides include aluminum hydroxide, magnesium hydroxide, etc. Examples of metal oxides include aluminum oxide, magnesium oxide, silicon oxide, zinc oxide, etc. Examples of metal nitrides include aluminum nitride, silicon nitride, boron nitride, etc.

[0021] Among these, metal hydroxides and / or metal oxides are preferably used, and aluminum hydroxide and / or aluminum oxide are more preferably used.

[0022] In one embodiment, the heat-dissipating filler (C1) is preferably surface-treated with a silane coupling agent, which makes the heat-dissipating filler (C1) more easily mixed with the resin and enhances the effect of suppressing an increase in viscosity.

[0023] Among these, as the heat-dissipating filler (C1), metal hydroxides and / or metal oxides that have been surface-treated with a silane coupling agent are preferably used, and more preferably aluminum hydroxide and / or aluminum oxide that have been surface-treated with a silane coupling agent are used.

[0024] The method of surface treatment with a silane coupling agent is not particularly limited, but examples thereof include dry treatment in which a solution containing a silane coupling agent is sprayed onto the heat-dissipating filler and mixed in a powder state.

[0025] The silane coupling agent used for the surface treatment of the heat dissipating filler is not particularly limited, and examples thereof include phenyl silane coupling agents, alkyl silane coupling agents, amino silane coupling agents, epoxy silane coupling agents, and vinyl silane coupling agents.

[0026] The phenyl silane coupling agent is a silane coupling agent having a phenyl group, and examples thereof include phenyltrialkoxysilanes such as phenyltriethoxysilane and phenyltrimethoxysilane, and diphenyldialkoxysilanes such as diphenyldimethoxysilane.

[0027] The alkylsilane coupling agent is a silane coupling agent that has an alkyl group directly bonded to a silicon atom and does not have an organic functional group such as an amino group, an epoxy group, or a vinyl group, and examples thereof include alkyltrialkoxysilane and dialkyldialkoxysilane.

[0028] The aminosilane coupling agent is a silane coupling agent having an amino group as an organic functional group, and examples thereof include 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropylmethyldimethoxysilane, and 3-anilinopropyltrimethoxysilane.

[0029] The epoxy silane coupling agent is a silane coupling agent having an epoxy group as an organic functional group, and examples thereof include 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0030] The vinyl silane coupling agent is a silane coupling agent having a vinyl group as an organic functional group, and examples thereof include vinyl trialkoxysilanes such as vinyl trimethoxysilane and vinyl triethoxysilane, and styryl silane coupling agents such as p-styryl trimethoxysilane.

[0031] The amount of silane coupling agent contained in the surface-treated heat-dissipating filler (C1) is not particularly limited, and may be, for example, 0.5 to 5 mass %, 0.6 to 3 mass %, or 0.7 to 1.5 mass % relative to 100 mass % of the heat-dissipating filler (C1) before surface treatment.

[0032] In this embodiment, the content of the heat-dissipating filler (C1) is 45 to 90 mass% relative to 100 mass% of the first component, preferably 50 to 90 mass%, more preferably 70 to 90 mass%, and even more preferably 80 to 90 mass%, relative to 100 mass% of the first component.

[0033] [Other ingredients] The first component may be composed of only the polyol (A) and the heat-dissipating filler (C1), but in addition to these components, it may also contain various additives, such as a moisture absorbent, an antifoaming agent, a dispersant, an antioxidant, a diluent, a flame retardant, an ultraviolet absorber, a colorant, and a plasticizer, as needed, within the scope of the present embodiment.

[0034] The moisture absorbent may be, for example, synthetic zeolite. The content of the adsorbent is not particularly limited, and may be, for example, 0.1 to 3 mass %, 0.3 to 2 mass %, or 0.5 to 1.5 mass % relative to 100 mass % of the first component.

[0035] Examples of antifoaming agents include polybutene and silicone resins, which may be used alone or in combination of two or more. The content of the antifoaming agent is not particularly limited, and may be, for example, 0.1 to 1 mass % or 0.3 to 0.7 mass % relative to 100 mass % of the first component.

[0036] The dispersant may be, for example, a phosphate ester surfactant. The content of the dispersant is not particularly limited, and may be, for example, 0.1 to 1 mass % or 0.3 to 0.7 mass % relative to 100 mass % of the first component.

[0037] <Second component> [Polyisocyanate (B)] The second component contains a polyisocyanate (B). The content of the polyisocyanate (B) may be, for example, 10 to 55% by mass, 15 to 50% by mass, 15 to 30% by mass, or 20 to 30% by mass relative to 100% by mass of the second component.

[0038] [Aliphatic polyisocyanate (b1)] The polyisocyanate (B) includes an aliphatic polyisocyanate (b1). Here, alicyclic polyisocyanates are not included in the aliphatic polyisocyanate (b1). Examples of the aliphatic polyisocyanate (b1) include tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, and derivatives thereof. These may be used alone or in combination of two or more.

[0039] Examples of the polyisocyanate derivative include modified products such as isocyanurates, adducts, biurets, allophanates, and carbodiimides, as well as isocyanate-terminated prepolymers obtained by reacting polyisocyanates with polyols. These derivatives are also included in the concept of aliphatic polyisocyanates (b1).

[0040] In one embodiment, the aliphatic polyisocyanate (b1) is contained in an amount of preferably 70 to 100 mass %, more preferably 80 to 100 mass %, even more preferably 90 to 100 mass %, and particularly preferably 100 mass %, based on 100 mass % of the polyisocyanate (B).

[0041] In one embodiment, HDI and / or a derivative thereof is preferably used as the aliphatic polyisocyanate (b1). The content of HDI and / or a derivative thereof is not particularly limited, and may be, for example, 70 to 100 mass%, 80 to 100 mass%, 90 to 100 mass%, or 100 mass% relative to 100 mass% of the aliphatic polyisocyanate (b1).

[0042] [Polyisocyanates other than aliphatic polyisocyanates (b1)] The polyisocyanate (B) may or may not contain a polyisocyanate other than the aliphatic polyisocyanate (b1). Examples of polyisocyanates other than the aliphatic polyisocyanate (b1) include alicyclic polyisocyanates and aromatic polyisocyanates. In one embodiment, the polyisocyanate (B) may contain an alicyclic polyisocyanate. Examples of alicyclic polyisocyanates include isophorone diisocyanate (IPDI) and derivatives thereof, which may be used alone or in combination of two or more. Among these, it is preferable to use IPDI and / or its derivatives as the polyisocyanate other than the aliphatic polyisocyanate (b1).

[0043] [Thermal filler (C2)] The second component contains a thermally conductive filler (C2). Specific examples of the thermally conductive filler (C2) include metal hydroxides, metal oxides, metal nitrides, and the like, which are similar to the thermally conductive filler (C1) described above in the first component. The thermally conductive filler (C1) used in the first component and the thermally conductive filler (C2) used in the second component may be the same or different.

[0044] In one embodiment, the heat-dissipating filler (C2) is preferably surface-treated with a silane coupling agent. The method of surface treatment with a silane coupling agent, the silane coupling agent used, and the amount thereof are as described above for the first component.

[0045] In this embodiment, the content of the heat-dissipating filler (C2) is 45 to 90 mass% relative to 100 mass% of the second component, and preferably 50 to 85 mass%, more preferably 70 to 85 mass%, and even more preferably 70 to 80 mass%, relative to 100 mass% of the second component.

[0046] The total content of the heat-dissipating filler (C1) and the heat-dissipating filler (C2) is not particularly limited, and may be, for example, 60 to 90 mass %, 65 to 88 mass %, or 70 to 86 mass % relative to the total amount of the two-component curing polyurethane resin composition.

[0047] [Other ingredients] The second component may be composed only of the polyisocyanate (B) and the heat-dissipating filler (C2), but in addition to these components, it may also contain various additives, such as a moisture absorbent, an antifoaming agent, a dispersant, an antioxidant, a diluent, a flame retardant, an ultraviolet absorber, a colorant, and a plasticizer, as needed, within the scope of the present embodiment.

[0048] In one embodiment, the mass ratio of the second component to the first component (second component / first component) is preferably 50 / 100 to 500 / 100, more preferably 80 / 100 to 450 / 100, even more preferably 100 / 100 to 250 / 100, and particularly preferably 110 / 100 to 200 / 100.

[0049] In the two-component curing polyurethane resin composition, the molar ratio of isocyanate groups to hydroxyl groups (NCO / OH) is not particularly limited and may be, for example, 0.75 to 2.3, 1.0 to 2.2, or 1.05 to 2.05. NCO / OH is calculated using the hydroxyl value of the polyol (A) and the isocyanate value of the polyisocyanate (B). Here, the isocyanate value is calculated using the isocyanate content measured in accordance with Method A of JIS K1603-1:2007, as follows: isocyanate value (mgKOH / g) = {(isocyanate content) × 56110} / (42.02 × 100).

[0050] The two-component curing polyurethane resin composition according to this embodiment is usually composed of a first liquid as the first component and a second liquid as the second component, but may also be provided with a third liquid that contains the above-mentioned other components as optional components in addition to the first and second liquids.

[0051] The two-component curing polyurethane resin composition can be produced by separately preparing the first and second components, and may contain the first and second components separately. That is, the resin composition may be a two-component kit in which the first and second components are filled in separate containers. The first and second components filled in separate containers are mixed at the time of use, causing the polyol (A) and polyisocyanate (B) to react to form a polyurethane resin, which then hardens to form a cured product. At this time, the curing may be carried out by heating. The two-component curing polyurethane resin composition according to the embodiment may be obtained by mixing the first and second components, or may be in a liquid state before curing.

[0052] When the thermally conductive filler (C1) is surface-treated with a silane coupling agent, it may be surface-treated before preparing the first liquid, or it may be surface-treated simultaneously with preparing the first liquid. That is, the surface-treated thermally conductive filler (C1) may be surface-treated by a method (integral blending method) in which polyol (A) and the thermally conductive filler (C1) before surface treatment are mixed and a silane coupling agent is added thereto. Furthermore, when the thermally conductive filler (C2) is surface-treated with a silane coupling agent, it is preferable to use the surface-treated filler before preparing the second liquid.

[0053] The use of the two-component curing polyurethane resin composition according to this embodiment is not particularly limited, but because of its advantages of excellent thermal conductivity and adhesiveness, it is preferably used as a heat-dissipating material. That is, the heat-dissipating material according to one embodiment includes the first and second components described above.

[0054] Heat dissipating materials are sometimes used, for example, in printed circuit boards, batteries, and the like, to efficiently transfer heat generated in a heat-generating component to a cooling component. In such cases, the heat dissipating material can be disposed between the heat-generating component and the cooling component. When the heat dissipating material is disposed between the heat-generating component and the cooling component, it is desirable that the heat dissipating material have excellent adhesive properties to the heat-generating component and the cooling component so that heat is efficiently transferred to the cooling component. The two-component curing polyurethane resin composition according to this embodiment has excellent adhesive properties, particularly to resins and metals. Therefore, by disposing the composition between a heat-generating component made of resin (e.g., polyester resin such as polyethylene terephthalate) and a cooling component made of metal (e.g., aluminum), it becomes possible to efficiently transfer heat generated in the heat-generating component to the cooling component. [Example]

[0055] The present invention will be explained in more detail below based on examples and comparative examples, but the present invention is not limited thereto.

[0056] Two-component curing polyurethane resin compositions were prepared according to the formulations (parts by mass) shown in the following Tables 1 to 5. Details of the raw materials used in the examples and comparative examples are as follows.

[0057] [Component (a1)] Octanediol: 2-ethyl-1,3-hexanediol (hydroxyl value = 767 mg KOH / g) PD9: 2,4-diethyl-1,5-pentanediol, "Kyowadiol PD-9" manufactured by KH Neochem Co., Ltd. (hydroxyl value = 701 mg KOH / g) MPD: 3-methyl-1,5-pentanediol, "Diol MPD" manufactured by Kuraray Co., Ltd. (hydroxyl value = 949 mg KOH / g)

[0058] [Component (a1')] Nonanediol: Crystalline alkanediol (hydroxyl value = 700 mg KOH / g) Triethylene glycol: Amorphous polyether diol (hydroxyl value = 747 mg KOH / g) Glycerin: Amorphous alkanetriol (hydroxyl value = 1828 mg KOH / g)

[0059] [(a2) component] Castor oil (hydroxyl value = 161 mg KOH / g, functional group number = 2.7) Exenol 430: Polyether polyol, AGC Corporation's "Exenol 430" (hydroxyl value = 420 mg KOH / g, functionality = 3) Exenol 1020: Polyether polyol, AGC Corporation's "Exenol 1020" (hydroxyl value = 112.2 mg KOH / g, functionality = 2) P510: Polyester polyol, Kuraray Co., Ltd. "Kuraray Polyol P-510" (hydroxyl value = 224 mg KOH / g, functionality = 2)

[0060] [(b1) component] HDI isocyanurate: Asahi Kasei Corporation's "Duranate TPA-100" (isocyanate value = 308.6 mg KOH / g) HDI prepolymer: Asahi Kasei Corporation's "Duranate D101" (isocyanate value = 263.1 mg KOH / g)

[0061] [Component (b2): Polyisocyanate other than component (b1)] IPDI prepolymer: isocyanate-terminated prepolymer of isophorone diisocyanate. The synthesis method is as follows: Isophorone diisocyanate, "EXCENOL 420" manufactured by AGC Corporation, and "NEOSTANN U-810" manufactured by Nitto Kasei Co., Ltd. were charged into a separable flask in a mass ratio of 46 / 54 / 0.03, and the mixture was stirred at 100°C for 2 hours under a nitrogen atmosphere to obtain an IPDI prepolymer (isocyanate value = 140 mgKOH / g).

[0062] [(C1) component, (C2) component] The following products were surface-treated with a silane coupling agent and used. The amounts (parts by mass) of the heat-dissipating filler (C1) and heat-dissipating filler (C2) in the table are the amounts (parts by mass) of the surface-treated products. The surface treatment method is as follows: An isopropyl alcohol solution of phenyltrimethoxysilane ("KBM-103" manufactured by Shin-Etsu Chemical Co., Ltd.) (mass ratio of phenyltrimethoxysilane / isopropyl alcohol = 50 / 50) was prepared. The prepared solution was sprayed onto the thermally conductive filler before surface treatment so that the concentration of phenyltrimethoxysilane was 1 mass% relative to 100 mass% of the thermally conductive filler, and the powder was mixed. The mixture was then cured in an open system at 80°C for 1 hour to obtain a thermally conductive filler surface-treated with phenyltrimethoxysilane. BX053: Aluminum hydroxide, surface-treated "BX053" manufactured by Nippon Light Metal Co., Ltd. CW-375HT: Aluminum hydroxide, surface-treated "CW-375HT" manufactured by Sumitomo Chemical Co., Ltd. DAW-45: Alumina, surface-treated "DAW-45" manufactured by Denka Co., Ltd. DAW-03: Alumina, surface-treated "DAW-03" manufactured by Denka Co., Ltd.

[0063] [Moisture absorbent] Molecular sieve 3AB: "Molecular sieve 3A-B POWDER" manufactured by Union Showa Co., Ltd.

[0064] [Antifoaming agent] LV-50: "Nisseki Polybutene LV-50" manufactured by ENEOS Materials Corporation KS-69: "KS-69" manufactured by Shin-Etsu Chemical Co., Ltd.

[0065] [Dispersant] A215C: Phosphate ester surfactant, "Plysurf A215C" manufactured by Daiichi Kogyo Seiyaku Co., Ltd.

[0066] The measurement and evaluation methods used in the examples are as follows.

[0067] [Viscosity of the first component] Approximately 100 g of the first component was mixed at 2,000 rpm for 1 minute using a mixer (Thinky Corporation's "Awatori Rentaro"). The viscosity of the mixture was measured at room temperature using a BH-type rotational viscometer (Toki Sangyo Co., Ltd.) with rotor No. 7 and 1 rpm. Viscosity less than 500,000 mPa·s was rated "A," 500,000 to 4,000,000 mPa·s was rated "B," and 4,000,000 mPa·s or greater was rated "C." A viscosity rating of "B" or higher for the first component is preferred.

[0068] [Thermal Conductivity] A two-component curing polyurethane resin composition was poured into a 5 mm thick mold and cured at 80°C for 16 hours (overnight) to produce a 5 mm thick resin sheet. The resin sheet was cut into 50 mm x 50 mm x 5 mm sheets to serve as measurement samples. Measurements were carried out using a "TCi" manufactured by C-Therm. Thermal conductivity was rated as "A" when it was 2.5 W / m·K or higher, "B" when it was 1.5 W / m·K or higher but less than 2.5 W / m·K, and "C" when it was less than 1.5 W / m·K. A thermal conductivity rating of "B" or higher is preferred.

[0069] [Adhesive (PET) and Adhesive (Aluminum)] Test specimens were prepared using two standard test plates (25 mm × 100 mm × 3 mm) with grips at both ends and an adhesive layer in the center where the two plates were stacked. The resin composition was applied so that the adhesive area was 25 mm × 25 mm and the adhesive layer thickness was 3 mm. The two plates were then stacked and cured by heating at 60 °C for 15 hours. The cured test specimens were subjected to a tensile shear test (tensile speed 12.5 mm / min) at 23 °C to measure shear strength. Adhesion (PET) was measured using a standard polyethylene terephthalate (PET) test plate, and adhesion (aluminum) was measured using a standard aluminum test plate. Shear strength at 23 °C of 4.5 MPa or greater or the standard test plate was destroyed was evaluated as "A," 1 MPa or greater but less than 4.5 MPa was evaluated as "B," and less than 1 MPa was evaluated as "C." Adhesion was preferably evaluated as "B" or higher.

[0070] [Table 1]

[0071] [Table 2]

[0072] [Table 3]

[0073] [Table 4]

[0074] [Table 5]

[0075] The results are shown in Tables 1 to 5. Comparative Example 1 is an example in which no amorphous alkanediol (a1) was blended, and although the viscosity and thermal conductivity of the first component were excellent, the adhesiveness was poor.

[0076] Comparative Example 2 is an example in which a crystalline alkanediol was blended instead of the amorphous alkanediol (a1), and evaluation was not possible due to crystallization. Comparative Example 3 is an example in which a non-crystalline polyether-based diol was blended instead of the amorphous alkanediol (a1), and the viscosity of the first component increased, making it impossible to prepare a test piece, and therefore thermal conductivity and adhesiveness could not be evaluated. Comparative Example 4 is an example in which a non-crystalline alkanetriol was blended instead of the amorphous alkanediol (a1), and the viscosity of the first component increased, making it impossible to prepare a test piece, making it impossible to evaluate thermal conductivity and adhesiveness.

[0077] Comparative Example 5 is an example in which the content of the heat-dissipating filler (C1) in the first component was below the lower limit. Although the viscosity and adhesiveness of the first component were excellent, the thermal conductivity was poor. Comparative Example 6 is an example in which the content of the heat-dissipating filler (C1) in the first component was above the upper limit. The viscosity of the first component increased, making it impossible to prepare test pieces, and therefore the thermal conductivity and adhesiveness could not be evaluated. Comparative Example 7 is an example in which the content of the heat-dissipating filler (C2) in the second component was below the lower limit. Although the viscosity and adhesiveness of the first component were excellent, the thermal conductivity was poor. Comparative Example 8 is an example in which the content of the heat-dissipating filler (C2) in the second component was above the upper limit. Since it was not possible to mix the second component, the thermal conductivity and adhesiveness could not be evaluated.

[0078] Comparative Example 9 is an example in which no aliphatic polyisocyanate (b1) was blended, and although the viscosity and thermal conductivity of the first component were excellent, the adhesiveness was poor.

[0079] Comparative Example 10 is an example in which the content of polyol (a2) was blended so as to be greater than the content of amorphous alkanediol (a1), and although the viscosity and thermal conductivity of the first component were excellent, the adhesiveness was poor.

[0080] In contrast to this, in Examples 1 to 19, the viscosity of the first component was low, and the thermal conductivity, adhesion to PET, and adhesion to aluminum were excellent.

[0081] The various numerical ranges described in this specification can be arbitrarily combined with their upper and lower limits, and all such combinations are considered to be preferred numerical ranges described in this specification. Furthermore, a numerical range described as "X to Y" means from X to Y.

[0082] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their omissions, substitutions, modifications, etc. are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents.

Claims

1. A two-component curable polyurethane resin composition comprising a first component containing a polyol (A) and a heat-dissipating filler (C1), and a second component containing a polyisocyanate (B) and a heat-dissipating filler (C2), the polyol (A) contains a non-crystalline alkanediol (a1) in an amount of 700 / 13% by mass or more and 100% by mass or less based on 100% by mass of the polyol (A), The polyisocyanate (B) contains 70 to 100% by mass of an aliphatic polyisocyanate (b1) based on 100% by mass of the polyisocyanate (B), the content of the heat-dissipating filler (C1) is 45 to 90% by mass relative to 100% by mass of the first component, The content of the heat-dissipating filler (C2) is 45 to 90% by mass relative to 100% by mass of the second component. A two-component curing polyurethane resin composition.

2. The two-component curable polyurethane resin composition according to claim 1, wherein the amorphous alkanediol (a1) has 6 or more and 9 or less carbon atoms.

3. 2. The two-component curing polyurethane resin composition according to claim 1, wherein the amorphous alkanediol (a1) comprises at least one selected from the group consisting of 2-ethyl-1,3-hexanediol, 2,4-diethyl-1,5-pentanediol, and 3-methyl-1,5-pentanediol.

4. 2. The two-component curing polyurethane resin composition according to claim 1, wherein the polyol (A) further comprises at least one selected from the group consisting of castor oil-based polyols, polyether polyols, and polyester polyols.

5. 2. The two-component curing polyurethane resin composition according to claim 1, wherein the heat-dissipating filler (C1) and the heat-dissipating filler (C2) are surface-treated with a silane coupling agent.

6. 2. The two-component curing polyurethane resin composition according to claim 1, wherein a mass ratio of the second component to the first component (second component / first component) is 50 / 100 to 500 / 100.

7. A heat dissipating material comprising the two-component curing polyurethane resin composition according to any one of claims 1 to 6.

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