JP2009234112A - Heat conductive laminate and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat conductive sheet which can temporarily fix itself to an exothermic electronic component or a heat radiating member because of having a moderate adhesiveness and which is good in reworkability because the adhesive strengths of both surfaces are different. <P>SOLUTION: The heat conductive laminate consists of a first cured product layer formed by curing a silicone composition 1 that contains (a) an organopolysiloxane having an alkenyl group, (b) a heat conductive filler, (c) an organohydrogenpolysiloxane, (d) a catalyst based on a platinum group metal, (e) a reaction controlling agent and (f) a silicone resin and a second cured product layer formed, on top of the first cured product layer, by curing a silicone composition 2 that contains the above (a)-(f) but differs in the composition from the silicone composition 1. The adhesive strengths of both surfaces are different from each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a thermally conductive laminate that can be interposed at a thermal interface between a heat-generating electronic component and a heat-dissipating member such as a heat sink or a circuit board, particularly for cooling the heat-generating electronic component, and a method for manufacturing the same. About.

  Electronic components such as CPUs, driver ICs, semiconductor elements such as memories, and light emitting elements such as LEDs used in electronic devices such as personal computers, digital video disks, and mobile phones are becoming more sophisticated, faster, smaller, and more expensive. Along with integration, itself generates a large amount of heat. The temperature rise of these exothermic electronic components due to the heat may cause malfunction and destruction of the exothermic electronic components themselves. Therefore, many heat dissipation methods for suppressing the temperature rise of the heat-generating electronic components during operation and heat dissipation members used for the heat dissipation methods have been proposed.

  Conventionally, in an electronic device or the like, a heat radiating member such as a heat sink using a metal plate having a high thermal conductivity such as aluminum or copper is used in order to suppress a temperature rise of a heat generating electronic component during operation. The heat radiating member conducts heat generated by the heat-generating electronic component, and releases the heat from the surface due to a temperature difference from the outside air.

  In order to efficiently conduct heat generated from the heat generating electronic component to the heat radiating member, it is effective to fill a slight gap generated between the heat generating electronic component and the heat radiating member with the heat conductive material. As the heat conductive material, a heat conductive sheet or a heat conductive grease blended with a heat conductive filler is used, and these heat conductive materials are interposed between a heat-generating electronic component and a heat dissipation member, Heat conduction from the heat-generating electronic component to the heat radiating member is realized through these heat conductive materials.

  Sheets are easier to handle than grease, and heat conductive sheets formed of heat conductive silicone rubber or the like are used in various fields.

  Thermally conductive sheets can be broadly classified into general products that emphasize handling and low hardness products that emphasize adhesion.

  Of these, general products are most often made of hard rubber with a hardness of 60 or more as measured by a type A durometer as defined in JIS K6253 in a sheet form. Can be handled. However, since this general product does not have a sticky feeling on the surface, it is difficult to fix the heat-generating electronic component and the heat dissipation member. In order to solve this, a tackiness imparting type has been proposed in which a pressure-sensitive adhesive is applied to one or both sides of a thin-film heat conductive sheet so that it can be easily fixed. However, since the applied adhesive does not have sufficient thermal conductivity, there is a problem that the thermal resistance of the adhesive-applied product is greatly increased compared to that without application. Moreover, the application of the pressure-sensitive adhesive adversely affects the thermal resistance in terms of increasing the thickness of the sheet itself.

  On the other hand, a low-hardness product is a sheet of a low-hardness heat conductive material having an Asuka-C hardness of 60 or less, and maintains an adhesive strength that can fix itself without applying an adhesive or the like. Yes. However, in order to realize the low hardness, a large amount of plasticizer is blended in the sheet or the crosslink density is very low, so there are difficulties in strength and handleability when forming a thin film. In order to obtain good handleability, a certain thickness or more is required. Therefore, it has been difficult to reduce the thermal resistance of the low hardness product. Further, such a low hardness product has a drawback that oil bleed is generated and a nearby heat-generating electronic component is easily contaminated.

  As a solution to these disadvantages, a thermally conductive adhesive tape has been developed that can be handled while being a thin film consisting of a single layer and that can be easily fixed to a heat-generating electronic component and a heat-dissipating member. (Patent Document 1). However, these heat conductive pressure-sensitive adhesive tapes have a uniform adhesive force, and cannot satisfy finer characteristic requirements such as single-sided strong adhesion and single-sided fine adhesion. For example, when a low-strength electronic element and a high-strength heat radiator are fixed with heat-adhesive tape and radiated, once the attachment fails, it is very difficult to peel off (rework), and it will be forcibly removed. Doing so will destroy the electronic device. In order to solve this, there is a method of controlling the adhesive force by performing dusting treatment etc. on one side of the adhesive tape, but in this case, the adhesion between the heat conductive adhesive tape and the adherend becomes poor, and the thermal conductivity is reduced. A problem of significant degradation occurs.

  In addition, Patent Documents 2 to 5 are disclosed as prior art related to the present invention.

Japanese Patent Laid-Open No. 2002-030212 JP 2005-035264 A JP 2005-206733 A JP 2006-182888 A JP 2006-188610 A

  Therefore, the problem of the present invention is that the thin film is easy to handle, has an appropriate adhesiveness, and can be easily fixed to a heat-generating electronic component or a heat radiating member by itself, and the adhesive strength on both sides is different, so the reworkability is good. Another object of the present invention is to provide a thermally conductive laminate having excellent thermal conductivity and a method for producing the same.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have made a heat conductive sheet, a layer made of a cured product of a specific addition reaction-curable silicone composition, and an addition reaction having a different composition. It has been found that this problem can be solved by constituting a laminate with a layer comprising a cured product of a curable silicone composition.

That is, the present invention firstly
(A) Organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule: 100 parts by volume
(B) Thermally conductive filler: 50 to 1,000 parts by volume,
(C) Organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: The molar ratio of hydrogen atoms bonded to silicon atoms in this component / alkenyl groups in component (a) is 0.00. An amount of 5 to 5.0,
(D) platinum group metal catalyst: effective amount,
(E) reaction control agent: effective amount, and (f) silicone resin: a first cured product layer formed by curing the silicone composition 1 containing 50 to 500 parts by volume into a thin film, and the above (a) A second cured product layer obtained by forming a silicone composition 2 containing the component (f) as an essential component and having a composition different from that of the silicone composition 1 into a thin film on one side of the first cured product layer and curing it. And a thermally conductive laminate having different adhesive strengths on both sides.

  The “capacity” when the blending amount of the component of the composition used in the present invention is represented by “volume part” means a value obtained by dividing the mass of the component by its true specific gravity.

  The following can be mentioned as preferable embodiment of the heat conductive laminated body of this invention.

  -At room temperature, one side of a 25 mm wide sample of the laminate was applied to an aluminum plate, pressure-bonded with a rubber roller having a mass of 2 kg, and cured for 10 minutes after bonding, and then the other not bonded to the aluminum plate of the laminate After adhering to the reinforcing material on one side, the laminate was gripped with one end of the adhering reinforcing material and peeled off from the aluminum plate in a 180 ° direction at a pulling speed of 300 mm / min. Force) is measured on both sides of the laminate, the adhesive strength on both sides is 0.3 N / cm or more, and the difference in adhesive strength on both sides is 2 N / cm or more. preferable. Examples of the reinforcing material include silicone tape and aluminum foil.

The silicone resin as the component (f) is composed of R ¹ ₃ SiO _1/2 units (R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond) and SiO _4/2 units. And the molar ratio of R ¹ ₃ SiO _1/2 units / SiO _4/2 units is preferably 0.5 to 1.5.

-The above-mentioned silicone composition 1 and / or silicone composition 2 are further used as component (g):
(G-1) The following general formula (1):
R ² _a R ³ _b Si (OR ⁴ ) _4-ab (1)
Wherein R ² is independently an alkyl group having 6 to 15 carbon atoms, R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ⁴ is independently And an alkyl group having 1 to 6 carbon atoms, a is an integer of 1 to 3, b is an integer of 0 to 2, provided that a + b is an integer of 1 to 3.)
And (g-2) the following general formula (2):

(In the formula, R ⁵ is independently an alkyl group having 1 to 6 carbon atoms, and c is an integer of 5 to 100.)
It is preferable to contain 0.01-50 volume part of at least 1 sort (s) chosen from the group which consists of dimethylpolysiloxane blocked with the trialkoxysilyl group at the molecular chain fragment end represented by

-Said silicone composition 1 and / or silicone composition 2 are further represented by the following general formula (3) as component (h):
R ^6- (SiR ⁶ ₂ O) _d SiR ⁶ ₂ -R ⁶ (3)
(R ⁶ is a monovalent hydrocarbon group which does not contain an aliphatic unsaturated bond having 1 to 18 carbon atoms, and d is an integer of 5 to 2,000.)
It is preferable to contain the organopolysiloxane whose kinematic viscosity in 23 degreeC represented by these is 10-100,000 mm < ² > / s.

  -It is preferable that the said heat conductive laminated body is 20-1,000 micrometers in thickness.

The thermal conductive laminate preferably has a thermal resistance at 25 ° C. measured by a laser flash method of 10 cm ² · K / W or less.

The present invention secondly,
(A) Organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule: 100 parts by volume
(B) Thermally conductive filler: 50 to 1,000 parts by volume,
(C) Organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: The molar ratio of hydrogen atoms bonded to silicon atoms in this component / alkenyl groups in component (a) is 0.00. An amount of 5 to 5.0,
(D) platinum group metal catalyst: effective amount,
(E) Reaction control agent: Effective amount, and (f) Silicone resin: Silicone composition 1 containing 50 to 500 parts by volume is formed into a thin film on the surface of a base material subjected to surface release treatment for silicone adhesive. A first cured product layer is formed by applying and curing, and then a silicone composition 2 containing the components (a) to (f) and having a composition different from that of the silicone composition 1 is formed on the first cured product layer. Provided is a method for producing a heat-conductive laminate having different adhesive strengths on both surfaces, which is formed by applying a thin film on the surface and curing to form a second cured product layer.

  One preferred embodiment of the production method of the present invention is a production method in which the release treatment for the silicone pressure-sensitive adhesive applied to the substrate is treatment with a modified silicone containing a fluorine substituent in the main chain. It is done.

  The heat conductive laminate of the present invention is very excellent in reworkability because it has different surface adhesiveness on both sides and can have different desired adhesive strength on each side. Since the adhesiveness of each surface of the thermally conductive laminate is moderate, it can be easily fixed by sticking to a heat-generating electronic component or a heat radiating member, and can be easily peeled off from the adherend if necessary. Therefore, the handleability is good. Moreover, when interposed between a heat-generating electronic component and a heat radiating member, both can be satisfactorily brought into contact with each other, and extremely good thermal conductivity is exhibited. Furthermore, oil bleed is suppressed and does not become a problem. Therefore, the laminate of the present invention is useful as a heat conductive sheet.

  Hereinafter, the present invention will be described in detail.

Although the heat conductive laminated body of this invention consists of a 1st hardened | cured material layer and a 2nd hardened | cured material layer, these contain the said (a)-(f) component as an essential component, but each has a different composition. It is formed from the composition which has. Hereinafter, the composition will be described.
[(A) Organopolysiloxane having an alkenyl group]
Component (a) of the composition of the present invention is an organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule, and is one of the main agents (base polymers) in the addition reaction curable composition of the present invention. One.

  The molecular structure of the organopolysiloxane is not limited as long as it is liquid, and examples thereof include a straight chain, a branched chain, and a partially branched straight chain, and a linear chain is particularly preferable.

  Here, the alkenyl group includes not only a linear alkenyl group but also a cycloalkenyl group. Specifically, examples of the alkenyl group include those having usually about 2 to 8 carbon atoms such as vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, hexenyl group, and cyclohexenyl group. Of these, a lower alkenyl group having 2 to 3 carbon atoms such as a vinyl group and an allyl group is preferable, and a vinyl group is particularly preferable. This alkenyl group may be bonded to either a silicon atom at the end of the molecular chain or a silicon atom in the middle of the molecular chain, but the silicon atom at the end of the molecular chain is used to make the resulting cured product flexible. It is preferable that it is bonded only to.

  The group bonded to the silicon atom other than the alkenyl group in the component (a) is, for example, an unsubstituted or substituted monovalent hydrocarbon group, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, Cycloalkyl groups such as isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, etc., cyclopentyl group, cyclohexyl group, cycloheptyl group , Aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group, biphenylyl group, aralkyl groups such as benzyl group, phenylethyl group, phenylpropyl group, methylbenzyl group, and carbon atoms of these groups Some or all of the hydrogen atoms are halogen atoms such as fluorine, chlorine, bromine, cyano groups, etc. Substituted groups such as chloromethyl, 2-bromoethyl, 3-chloropropyl, 3,3,3-trifluoropropyl, chlorophenyl, fluorophenyl, cyanoethyl, 3,3,4,4 , 5, 5, 6, 6, 6-nonafluorohexyl group and the like having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms. Among these, methyl group, ethyl group are preferable. , A propyl group, a chloromethyl group, a bromoethyl group, a 3,3,3-trifluoropropyl group, an unsubstituted or substituted alkyl group having 1 to 3 carbon atoms such as a cyanoethyl group, and a phenyl group, a chlorophenyl group, a fluorophenyl An unsubstituted or substituted phenyl group such as a group. All the groups bonded to the silicon atom other than the alkenyl group may be the same or different. Unless special properties such as solvent resistance are required, a methyl group is often selected for reasons such as cost, availability, chemical stability, and environmental burden.

Moreover, kinematic viscosity at 25 ° C. This organopolysiloxane is usually, 10~100,000mm ² / s, particularly preferably from 500~50,000mm ² / s. If the viscosity is too low, the storage stability of the resulting composition will be poor, and if it is too high, the extensibility of the resulting composition may be poor.

  Preferable specific examples of such organopolysiloxanes include dimethylvinylsiloxy group-capped polydimethylsiloxane having molecular chains at both ends, methyldivinylsiloxy group-capped polydimethylsiloxane having molecular chains at both ends, and dimethylvinylsiloxy-capped dimethylsiloxane having molecular chains at both ends. -A methylphenylsiloxane copolymer etc. are mentioned.

  The organopolysiloxane of component (a) can be used singly or in combination of two or more having different viscosities.

[(B) Thermally conductive filler]
As the thermally conductive filler that is component (b), for example, metal powder, metal oxide powder, and ceramic powder are usually used. Specifically, aluminum powder, copper powder, silver powder, nickel powder, gold powder, and the like are used. Powder, aluminum oxide powder, zinc oxide powder, magnesium oxide powder, iron oxide powder, titanium oxide powder, zirconium oxide powder, aluminum nitride powder, boron nitride powder, silicon nitride powder, diamond powder, carbon powder, fullerene powder, carbon graphite powder Etc. However, the present invention is not limited thereto, and any filler may be used as long as it is a known substance conventionally used as a thermally conductive filler, and these may be used alone or in combination of two or more.

  As these heat conductive fillers, those having an average particle diameter of usually 0.1 to 100 μm, preferably 0.5 to 50 μm can be used. These fillers may be used individually by 1 type, and may mix and use multiple types. Two or more kinds of particles having different average particle diameters can be used. In addition, in this invention, an average particle diameter is a volume average particle diameter, and is a measured value by the micro track particle size distribution measuring apparatus MT3300EX (Nikkiso Co., Ltd.).

  The blending amount of the heat conductive filler is 50 to 1,000 parts by volume, preferably 100 to 100 parts by volume with respect to 100 parts by volume of the component (a), from the viewpoint of fluidity, moldability, and heat conductivity to be obtained. 500 parts by volume.

[(C) Organohydrogenpolysiloxane]
The component (c) of the composition of the present invention is usually an organohydrogenpolysiloxane having 2 or more, preferably 2 to 100, hydrogen atoms (that is, SiH groups) bonded to silicon atoms in one molecule. (A) It is a component which acts as a crosslinking agent for the component. That is, the hydrogen atom bonded to the silicon atom in the component (c) is added by the hydrosilylation reaction with the alkenyl group in the component (a) by the action of the platinum group metal catalyst of the component (d) described later, A crosslinked cured product having a three-dimensional network structure having crosslinked bonds is obtained.

  Examples of the organic group bonded to the silicon atom in the component (c) include an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bond. Specifically, the component (a) Examples thereof include unsubstituted or substituted hydrocarbon groups of the same type as those exemplified as the group bonded to the silicon atom other than the alkenyl group described in the section. Among them, a methyl group is preferable from the viewpoint of synthesis and economy.

  The structure of the organohydrogenpolysiloxane of component (c) is not particularly limited, and may be any of linear, branched and cyclic, but is preferably linear. Such a linear organohydrogenpolysiloxane includes, for example, the following general formula (4):

(Wherein R ⁷ is independently an unsubstituted or substituted monovalent hydrocarbon group other than an alkenyl group or a hydrogen atom, provided that at least two are hydrogen atoms and n is an integer of 1 or more.)
It is represented by

In the general formula (4), the unsubstituted or substituted monovalent hydrocarbon group other than the alkenyl group represented by R ⁷ is a group bonded to a silicon atom other than the alkenyl group described above in the section of the component (a). It is the same kind as the monovalent hydrocarbon group therein.

  N is preferably an integer of 2 to 100, more preferably 5 to 50.

  Preferable specific examples of the organohydrogenpolysiloxane of component (c) include molecular chain both ends trimethylsiloxy group-capped methylhydrogen polysiloxane, molecular chain both ends trimethylsiloxy group-capped dimethylsiloxane / methylhydrogensiloxane copolymer , Dimethylsiloxane / methylhydrogensiloxane / methylphenylsiloxane copolymer blocked with trimethylsiloxy group blocked at both ends of molecular chain, dimethylpolysiloxane blocked with dimethylhydrogensiloxy group blocked at both ends of molecular chain, dimethylsiloxane with dimethylhydrogensiloxy group blocked at both ends of molecular chain・ Methylhydrogensiloxane copolymer, dimethylhydrogensiloxy group-blocked dimethylsiloxane at both molecular chains ・ Methylphenylsiloxane copolymer, dimethylhigh at both molecular chains Rojenshirokishi groups at methylphenyl polysiloxane and the like. The (c) component organohydrogenpolysiloxane can be used singly or in combination of two or more.

  Component (c) is added in an amount such that the SiH group of component (c) is 0.5 to 5.0 moles per mole of alkenyl group in component (a), preferably 0.8 to 4. The amount is 0 mol. If the amount of Si-H groups in component (c) is less than 0.5 moles relative to 1 mole of alkenyl groups in component (a), the thermally conductive composition will not cure or the strength of the cured product will be insufficient. The problem that it becomes impossible to handle as a molded body or a laminate occurs. If the amount exceeds 5.0 moles, the cured product will not have sufficient adhesiveness, and the problem that it cannot be fixed with its own adhesive will occur.

[(D) Platinum group metal catalyst]
The platinum group metal catalyst of component (d) in the present invention promotes the addition reaction between the alkenyl group in component (a) and the hydrogen atom bonded to the silicon atom in component (c), and the composition of the present invention. To the three-dimensional network structure to give a cross-linked cured product.

(D) As a component, all the well-known catalysts used for normal hydrosilylation reaction can be used. Specific examples thereof include platinum group metals such as platinum (including platinum black), rhodium and palladium, H ₂ PtCl ₄ · nH ₂ O, H ₂ PtCl ₆ · nH ₂ O, NaHPtCl ₆ · nH ₂ O. , KHPtCl ₆ · nH ₂ O, Na ₂ PtCl ₆ · nH ₂ O, K ₂ PtCl ₄ · nH ₂ O, PtCl ₄ · nH ₂ O, PtCl ₂ , Na ₂ HPtCl ₄ · nH ₂ O (where, n is an integer of 0 to 6, preferably 0 or 6.), etc.), such as platinum chloride, chloroplatinic acid and chloroplatinate, alcohol-modified chloroplatinic acid, chloroplatinic acid and olefin complex, platinum black , Platinum group metals such as palladium supported on a carrier such as alumina, silica, carbon, rhodium-olefin complex, chlorotris (triphenylphosphine) rhodium (Wilkinso Catalyst), platinum chloride, chloroplatinic acid or chloroplatinate and a vinyl group-containing siloxane. The platinum group metal catalyst of component (d) can be used singly or in combination of two or more.

  (D) The compounding quantity of a component should just be an effective amount required in order to harden the composition of this invention, Although it does not restrict | limit, Usually, it is 0 in conversion of the mass of the platinum group metal element with respect to (a) component. .1 to 1,000 ppm, preferably 0.5 to 500 ppm.

[(E) Reaction control agent]
The (e) component reaction control agent is for adjusting the reaction rate of the (a) component and the (c) component that proceed in the presence of the (d) component.

  As the component (e), all known addition reaction inhibitors used in ordinary addition reaction curable silicone compositions can be used. Specific examples thereof include acetylene compounds such as 1-ethynyl-1-cyclohexanol and 3-butyn-1-ol, nitrogen compounds, organic phosphorus compounds, sulfur compounds, oxime compounds, and organic chloro compounds. In addition, the addition reaction inhibitor of (e) component can be used even if single 1 type also combines 2 or more types.

  The amount of component (e) varies depending on the amount of component (d) used, and thus cannot be defined unconditionally. However, it may be any effective amount that can adjust the progress of the hydrosilylation reaction to a desired reaction rate. It is good to set it as about 10-50000 ppm with respect to the mass of a) component. If the amount of component (e) is too small, sufficient pot life may not be ensured, and if too large, the curability of the composition may be reduced.

[(F) Silicone resin]
The silicone resin of component (f) used in the present invention has an effect of imparting tackiness to the cured product of the present invention.

Examples of the component (f) include a copolymer of R ¹ ₃ SiO _1/2 unit (M unit) and SiO _4/2 unit (Q unit), wherein the ratio of M unit to Q unit (molar ratio). ) Is M / Q = 0.5 to 1.5, preferably 0.6 to 1.4, more preferably 0.7 to 1.3. A desired adhesive strength can be obtained in the range of M / Q = 0.5 to 1.5.

R ¹ is an unsubstituted or substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl Group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, alkyl group such as dodecyl group, cycloalkyl group such as cyclopentyl group, cyclohexyl group, cycloheptyl group, phenyl group, tolyl group, xylyl group An aryl group such as a naphthyl group and a biphenylyl group, an aralkyl group such as a benzyl group, a phenylethyl group, a phenylpropyl group and a methylbenzyl group, and a part or all of hydrogen atoms bonded to carbon atoms of these groups , Groups substituted by halogen atoms such as fluorine, chlorine, bromine, cyano groups, etc., for example, chloromethyl Group, 2-bromoethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, chlorophenyl group, fluorophenyl group, cyanoethyl group, 3,3,4,4,5,5,6,6, Examples include 6-nonafluorohexyl group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, and among these, methyl group, ethyl group, propyl group, chloromethyl group, bromoethyl are preferable. Group, an unsubstituted or substituted alkyl group having 1 to 3 carbon atoms such as 3,3,3-trifluoropropyl group, cyanoethyl group and the like, and an unsubstituted or substituted phenyl group such as phenyl group, chlorophenyl group, fluorophenyl group, etc. It is. R ¹ may be all the same or different. As for R ¹ , a methyl group is often selected for reasons such as cost, availability, chemical stability, and environmental burden unless special characteristics such as solvent resistance are required.

  The amount of component (f) added is 50 to 500 parts by volume, preferably 60 to 350 parts by volume, and more preferably 70 to 200 parts by volume with respect to 100 parts by volume of component (a). If the amount of component (f) added is less than 50 parts by volume or more than 500 parts by volume, the desired tackiness cannot be obtained.

  The component (f) itself is a solid or viscous liquid at room temperature, but can also be used in a state dissolved in a solvent. In that case, the amount added to the composition is determined by the amount excluding the solvent.

[Other ingredients]
In the composition (silicone composition 1 and / or silicone composition 2) used in the present invention, if necessary, components other than the components (a) to (f) as long as the object of the present invention is not impaired. Can be added. Hereinafter, such optional components will be described.

(G) Surface treatment agent:
In the composition of the present invention, at the time of preparing the composition, (b) the thermally conductive filler is hydrophobized to improve the wettability with (a) the organopolysiloxane, and (b) the thermally conductive filler is ( A surface treating agent (wetter) can be blended for the purpose of uniformly dispersing in the matrix comprising the component a). As the component (g), the following (g-1) and (g-2) are particularly preferable.

(G-1) Alkoxysilane compound The following general formula (1):
R ² _a R ³ _b Si (OR ⁴ ) _4-ab (1)
Wherein R ² is independently an alkyl group having 6 to 15 carbon atoms, R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ⁴ is independently And an alkyl group having 1 to 6 carbon atoms, a is an integer of 1 to 3, b is an integer of 0 to 2, provided that a + b is an integer of 1 to 3.)
It is the alkoxysilane compound represented by these.

In the general formula (1), examples of the alkyl group represented by R ² include a hexyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, and a tetradecyl group. When the number of carbon atoms of the alkyl group represented by R ² satisfies the range of 6 to 15, the wettability of the component (b) is sufficiently improved, the handling workability is good, and the low temperature characteristics of the composition are good. It will be a thing.

Examples of the unsubstituted or substituted monovalent hydrocarbon group represented by R ³ include alkyl groups such as a methyl group, an ethyl group, a propyl group, a hexyl group, and an octyl group; and a cycloalkyl such as a cyclopentyl group and a cyclohexyl group. Groups: alkenyl groups such as vinyl and allyl groups; aryl groups such as phenyl and tolyl groups; aralkyl groups such as 2-phenylethyl and 2-methyl-2-phenylethyl groups; 3,3,3-trifluoro Examples thereof include halogenated hydrocarbon groups such as propyl group, 2- (nonafluorobutyl) ethyl group, 2- (heptadecafluorooctyl) ethyl group, and p-chlorophenyl group. Among these, a methyl group and an ethyl group are particularly preferable.

Examples of the alkyl group represented by R ⁴ include alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Among these, a methyl group and an ethyl group are particularly preferable.

  Preferable specific examples of the component (g-1) include the following.

C ₆ H ₁₃ Si (OCH ₃ ) ₃
C ₁₀ H ₂₁ Si (OCH ₃ ) ₃
C ₁₂ H ₂₅ Si (OCH ₃ ) ₃
C ₁₂ H ₂₅ Si (OC ₂ H ₅ ) ₃
C ₁₀ H ₂₁ Si (CH ₃ ) (OCH ₃ ) _{2
C 10 H 21 Si (C 6} H 5) (OCH 3) 2
_{C 10 H 21 Si (CH 3} ) (OC 2 H 5) 2
C ₁₀ H ₂₁ Si (CH═CH ₂ ) (OCH ₃ ) _{2
C 10 H 21 Si (CH 2} CH 2 CF 3) (OCH 3) 2

  In addition, (g-1) component can be used even if single 1 type also combines 2 or more types. Even if the blending amount of the component (g-1) exceeds a certain amount, the wetter effect does not increase any more, which is uneconomical. In addition, since the component is volatile, the composition and the cured product after curing may gradually become hard if left in an open system.

(G-2) Dimethylpolysiloxane The following general formula (2):

(In the formula, R ⁵ is independently an alkyl group having 1 to 6 carbon atoms, and c is an integer of 5 to 100.)
Is a dimethylpolysiloxane in which one end of a molecular chain represented by is blocked with a trialkoxysilyl group.

In the general formula (2), the alkyl group represented by R ⁵ is the same type as the alkyl group represented by R ⁴ in the general formula (1).

  Preferable specific examples of the component (g-2) include the following.

  In addition, (g-2) component can be used even if single 1 type also combines 2 or more types. When there are too many compounding quantities of this (g-2) component, there exists a tendency for the heat resistance and moisture resistance of the hardened | cured material obtained to fall.

  As the surface treatment agent for the component (g), either one of the components (g-1) and (g-2) may be used in combination. In this case, the blending amount of the component (g) is preferably 0.01 to 50 parts by volume, particularly 0.1 to 30 parts by volume with respect to 100 parts by volume of the component (a).

(H) Organopolysiloxane:
In the composition of the present invention, the following general formula (3):
R ^6- (SiR ⁶ ₂ O) _d SiR ⁶ ₂ -R ⁶ (3)
(R ⁶ is a monovalent hydrocarbon group which does not contain an aliphatic unsaturated bond having 1 to 18 carbon atoms, and d is an integer of 5 to 2,000.)
It is possible to add an organopolysiloxane having a kinematic viscosity at 23 ° C. of 10 to 100,000 mm ² / s. Although it is suitably used for the purpose of imparting properties such as a viscosity modifier of the thermally conductive composition, it is not limited thereto. One kind may be used alone, or two or more kinds may be used in combination.

R ⁶ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms. Examples of R ⁶ include alkyl groups such as methyl, ethyl, propyl, hexyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl; cyclohexyl groups such as cyclopentyl and cyclohexyl. Aryl groups such as phenyl group and tolyl group; aralkyl groups such as 2-phenylethyl group and 2-methyl-2-phenylethyl group; 3,3,3-trifluoropropyl group, 2- (perfluorobutyl) ethyl Group, 2- (perfluorooctyl) ethyl group, halogenated hydrocarbon group such as p-chlorophenyl group, and the like are mentioned, and methyl group, phenyl group and alkyl group having 6 to 18 carbon atoms are particularly preferable.

  From the viewpoint of the required viscosity, d is preferably an integer of 5 to 2,000, and particularly preferably an integer of 10 to 1,000.

Further, the kinematic viscosity at 25 ° C., preferably a 10~100,000mm ² / s, it is preferable in particular 100~10,000mm ² / s. When the kinematic viscosity is lower than 10 mm ² / s, the cured product of the resulting composition tends to generate oil bleeding. If the kinematic viscosity is greater than 100,000 mm ² / s, the fluidity of the resulting heat conductive composition tends to be poor.

  Specific examples of the component (h) include, for example,

Etc.

  When the component (h) is added to the composition of the present invention, the amount added is not limited and may be any amount that provides the desired effect, but is preferably 0 with respect to 100 parts by volume of the component (a). .1 to 100 parts by volume, more preferably 1 to 50 parts by volume. When the added amount is within this range, it is easy to maintain good fluidity and workability in the thermally conductive composition before curing, and the composition is filled with the thermally conductive filler of component (b). Easy to do.

・ Other optional ingredients:
Other optional components include, for example, fluorine-modified silicone surfactants; carbon black, titanium dioxide, bengara, etc. as colorants; metal oxides such as platinum compounds, iron oxides, titanium oxides, cerium oxides as flame retardants, Alternatively, a metal hydroxide or the like may be added. Furthermore, it is optional to add fine powder silica such as precipitated silica or calcined silica, thixotropic improver, etc. as an anti-settling agent for the heat conductive filler.

(Formation of laminate)
Two or more kinds of the compositions of the present invention (composition 1 and composition 2), each having a different composition and mixed uniformly with the required components, are prepared. First, one composition 1 is applied and molded on a base material and cured by heating to form a first layer. Next, another type of composition (Composition 2) is applied and formed on one side of the first layer, and is cured by heating. Thus, the heat conductive laminate of the present invention can be obtained. When applying and molding the composition on the substrate or the first layer, it is possible to add a solvent such as toluene to adjust the viscosity of the composition.

  The thicknesses of the first and second hardened layers are each preferably 10 to 500 μm, and more preferably 20 to 250 μm. The thickness of the entire laminate is preferably 20 to 1,000 μm, and more preferably 50 to 500 μm. If the thickness is too thin, the laminate is poorly handled and the tackiness is lowered. On the other hand, if the thickness is too thick, desired thermal conductivity cannot be obtained.

〔Characteristic〕
·Thermal resistance:
The heat conductive laminate of the present invention preferably has a thermal resistance at 25 ° C. measured by a laser flash method of 10 cm ² · K / W or less, particularly preferably 5 cm ² · K / W or less. When the thermal resistance is within this range, the composition of the present invention can efficiently dissipate heat generated from the heating element to the heat radiating component even when applied to a heating element having a large calorific value. In addition, the measurement of the thermal resistance by the laser flash method can be performed in accordance with ASTM E 1461.

・ Adhesiveness:
The heat conductive laminate of the present invention is characterized by having different adhesive forces on both sides. A sample of a 25 mm wide laminate was prepared, and at room temperature, one side of the laminate was applied to an aluminum plate at room temperature, and the laminate was pressed by a rubber roller having a mass of 2 kg and then cured for 10 minutes. Along with the above-mentioned reinforcing material to which one end of the laminated body is bonded after bonding a tape-shaped reinforcing material made of a 25 mm width silicone tape (Nippa Co., Ltd., No. 99) to the other surface not bonded to the aluminum plate When peeled from the aluminum plate and grasped and peeled off from the aluminum plate in a 180 ° direction at a pulling speed of 300 mm / min, the force required for peeling (referred to as “adhesive strength”) was measured. The difference in adhesive force between both surfaces (strongly adhesive side and weakly adhesive side) is preferably 2 N / cm or more, and particularly preferably 3 / cm or more. When the difference in the adhesive strength between the two surfaces of the laminate is less than 3 N / cm, a significant difference in the adhesive properties between the two surfaces is difficult to develop, and the adherend may be damaged during rework or adhesive peeling.

  The adhesive strength measured as described above is desirably 0.3 N / cm or more, particularly 0.5 to 20 N / cm, on both sides. When either one of the adhesive strengths is less than 0.3 N / cm, it becomes difficult to fix the heat-generating electronic component or the heat radiating member with its own adhesive strength. Moreover, since it will not peel easily when adhesive force is too large, rework property is inferior.

  The silicone composition 1 and the silicone composition 2 are selected so that the adhesive strength on both surfaces of the laminate of the present invention has such a value. This selection is made by changing the composition of the silicone composition of the present invention, applying it to a substrate and curing it to form a cured layer, and testing the adhesive strength in the same manner as above for each composition. The adhesive strength can be determined. Next, the laminate of the present invention can be easily produced by selecting and combining the two silicone compositions so that the adhesive strength satisfies the above conditions.

[Method for producing thermally conductive laminate]
The thermally conductive laminate of the present invention was subjected to, for example, the above-described method, that is, the silicone composition 1 containing a predetermined amount of each of the components (a) to (f) was subjected to a surface release treatment for a silicone adhesive. A thin film is applied to the surface of the substrate and cured to form a first cured product layer, and then a silicone composition 2 containing the components (a) to (f) and having a composition different from that of the silicone composition 1 is prepared. It can manufacture by apply | coating to a thin film form on the surface of said 1st hardened | cured material layer, making it harden | cure, and forming a 2nd hardened | cured material layer.

In the above method, the blending order of each component when preparing the composition 1 or the composition 2 is not particularly limited, but as a preferred method,
(1) A base composition is prepared by kneading a required amount of the components (a), (b), and (d).
(2) Separately, preparing a curing agent obtained by mixing the components (c) and (e).
(3) Next, preparing the composition which mixed said base composition, hardening | curing agent, and the silicone resin of (f) component uniformly is mentioned.

  As the base material used in the method of the present invention, that is, the base material to which the silicone composition 1 is applied, a paper, a PET film or the like subjected to a surface release treatment for a silicone adhesive is suitable. Examples of the surface release agent for silicone pressure-sensitive adhesives include modified silicones having a fluorine substituent such as a perfluoroalkyl group and a perfluoropolyether group in the main chain.

  The perfluoropolyether group can be represented by the following formulas (5) to (7).

  Specific examples of the modified silicone having a fluorine substituent include products such as trade names: X-70-201 and X-70-258 manufactured by Shin-Etsu Chemical Co., Ltd.

  Examples of the method for applying and molding the composition on the substrate include applying a liquid material in a thin film on the substrate using a bar coater, knife coater, comma coater, spin coater, etc. The method is not limited.

  Moreover, the heating temperature conditions for heating after shaping | molding should just be the temperature which the solvent used when the solvent was added volatilizes and (a) component and (c) component can react. In view of productivity and influence on the substrate film, 50 to 150 ° C. is desirable, and 60 to 150 ° C. is more desirable. The curing time may usually be 0.5 to 30 minutes, preferably 1 to 20 minutes. Even when heating is performed at the same temperature, a heating method in which the temperature is changed by step-up or ramp-up may be employed.

  The thermally conductive laminate after curing can be transported and scaled by laminating the same release treatment film as the substrate film on the surface opposite to the substrate side of the laminate as a protective separator film. Handling such as cutting can be facilitated. At this time, it is possible to change the processing amount and type of the release agent with the base film, or change the material of the base material to give light weight to the adhesive force from the laminate of the base film and the separator film. .

  The heat conductive laminate thus obtained is a thin film by peeling off the separator film or substrate film, and then sticking it to the heat-generating electronic component or heat dissipation member, and then peeling off the remaining film. However, it can be easily arranged and exhibits excellent heat conduction characteristics. Moreover, since adhesiveness differs in both surfaces, at the time of a rework or adhesive peeling, peeling on a desired surface (weak adhesion side) can be performed, maintaining the adhesion on the strong adhesion side. Thereby, in the weak adhesion side, the stress added to a to-be-adhered body is reduced, and it becomes possible to prevent a failure | damage.

  EXAMPLES Hereinafter, although the Example and comparative example of this invention are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.

First, the components (a) to (f) used in the following examples and comparative examples are shown below.
<(A) component>
(A-1) Dimethylpolysiloxane having a kinematic viscosity at 25 ° C. of 600 mm ² / s and having both molecular chain ends blocked with dimethylvinylsiloxy groups. (A-2) Kinematic viscosity at 25 ° C. of 30,000 mm ² / s, dimethylpolysiloxane with both molecular chain ends blocked with dimethylvinylsiloxy groups

<(B) component>
(B-1) Alumina powder having an average particle diameter of 10.7 μm (true specific gravity 3.98)
(B-2) Alumina powder having an average particle size of 1.1 μm (true specific gravity: 3.98)
(B-3) Zinc oxide powder having an average particle size of 0.6 μm (true specific gravity 5.67)

<(C) component>
(C-1) The following structural formula:

Organohydrogenpolysiloxane represented by

<(D) component>
(D-1) dimethylpolysiloxane of platinum-divinyltetramethyldisiloxane complex (both ends of molecular chain blocked with dimethylvinylsilyl group, solution having a kinematic viscosity at 25 ° C. of 600 mm ² / s [containing platinum atom (Amount: 1% by mass)

<(E) component>
(E-1) 50% by mass toluene solution of 1-ethynyl-1-cyclohexanol

<Component (f)>
(F-1) Toluene solution (non-volatile content 60) of silicone resin (M / Q molar ratio 1.15) consisting essentially of Me ₃ SiO _0.5 units (M units) and SiO ₂ units (Q units) %; Viscosity 30 mm ² / s).
(F-2) A toluene solution (nonvolatile content 70) of a silicone resin (M / Q molar ratio 0.85) substantially composed of only Me ₃ SiO _0.5 units (M units) and SiO ₂ units (Q units). %; Viscosity 30 mm ² / s).

<(G) component>
(G-1) Structural formula: Organosilane represented by C ₁₂ H ₂₅ Si (OC ₂ H ₅ ) ₃ (G-2) Structural formula:

A dimethylpolysiloxane blocked with a trimethoxysilyl group blocked by a molecular chain represented by

<(H) component>
(H-1) Structural formula:

Dimethylpolysiloxane having a kinematic viscosity at 25 ° C. of 600 mm ² / s represented by

<Base material>
(K-1) 100 μm thick PET film coated with 1.0 g / m ² of X-70-201 manufactured by Shin-Etsu Chemical Co., Ltd. (K-2) Untreated PET film with a thickness of 100 μm

[Preparation Examples 1-4, Comparative Preparation Examples 1-4]
<Preparation of thermal conductive composition>
Components S1 to S7 were prepared by blending the components described in Table 1 in the following amounts (parts by mass) in the same table as follows. Compositions S5, S6 and S7 are compositions that do not satisfy the conditions of the present invention.

  To a planetary mixer (trade name: TK Hibismix manufactured by Tokushu Kika Kogyo Co., Ltd.) with an internal volume of 700 ml, (a) component, (b) component, and optionally (g) component and (h) The ingredients were charged and mixed for 60 minutes. Next, the components (d) and (e) were added and mixed uniformly. Finally, the components (c) and (f) were added and mixed uniformly to prepare a composition.

<< Note 1 >>: The numerical value in parentheses in the table is the volume part of resin in the component (f) with respect to 100 volume parts of the component (a).

<< Note 2 >>: The concentrations of the component (d) and the component (e) in the table are the concentrations of the component (D-1) and the component (E-1) with respect to the mass of the component (a). The numerical value in parentheses is the concentration of (D-1) component as platinum atom relative to the mass of component (a) and 1-ethynyl-1-cyclohexanol contained in component (E-1) relative to the mass of component (a) Concentration.

<< Note 3 >>: “SiH / Vi” means the number of SiH groups (hydrogen atoms bonded to silicon atoms) in the component (B) with respect to one vinyl group in the component (A).

[Examples 1 to 4, Comparative Examples 1 to 5]
<Manufacture of laminates>
The laminates described in Tables 2 and 3 were obtained as follows using the conditions described in the same table. First, among the compositions obtained in Table 1, one type (X1) was selected, applied to a substrate, and cured to obtain a single layer (Y1) of a thermally conductive cured product. Subsequently, one type (X2) of the compositions obtained in Table 1 was further selected and applied on the single layer body of the thermally conductive cured material obtained earlier, and then cured, and the laminate (Y2 )

  About the obtained laminated body, the following method evaluated adhesiveness, rework property, selective peelability, bleeding property, peelability from a base material, the handleability after peeling, and thermal resistance. The results are shown in Table 2 and Table 3.

・ Peelability:
It evaluated by the weight at the time of peeling the heat conductive laminated body after hardening from a base film by hand (evaluation by a touch). When the feel of peeling was light and the laminate did not deform at all, it was evaluated as “good”, and when the feel of peeling was heavy or when the laminate was deformed, it was evaluated as “bad”.

・ Handability after peeling:
The handleability of the thermally conductive cured product after peeling was evaluated by paying attention to the shape of the main body. When the thermally conductive cured product peeled off from the base film was adhered to an aluminum plate, it was evaluated as “good” when it could be adhered without difficulty. When the thermally conductive cured product was cracked or firmly adhered to the hand and deformed, and the original shape could not be recovered, it was judged as “bad”.

・ Rework and selective peelability:
The both sides of the heat-conductive cured product after peeling are sandwiched between the same aluminum plates, reworkability (does not damage the adhesive when peeling), and selective peelability (whether it is always peeled from the weak adhesive side) ) Was evaluated.

  The test of peeling off the two aluminum plates bonded via the thermally conductive cured product was repeated 5 times (the thermally conductive cured product and the aluminum plate were exchanged for each test). When the thermally conductive cured product is peeled off from the aluminum plate that is bonded to the weakly adhesive surface without deformation or destruction of the aluminum plate that is bonded to both sides, it is evaluated as “good”. When the thermally conductive cured product was peeled off from the aluminum plate bonded to the strong surface, the aluminum plate or the thermally conductive cured product was evaluated as “bad” when deformed or destroyed.

・ Adhesiveness:
In the manner described above, the thermally conductive laminate is bonded to an aluminum plate on each side with a 2 kg rubber roller and then cured for 10 minutes, and the other side not bonded to the aluminum plate is attached to prevent the laminate from being deformed. After bonding with a strong silicone adhesive tape (manufactured by Nipper Co., Ltd.), one end was peeled off and grasped by hand, and then peeled off at 180 ° at a pulling speed of 300 mm / min at room temperature to measure the adhesive force. The measurement results are shown in Table 2 and Table 3.

・ Bleedability:
Cut a 0.1mm thick sample into a 20mm square together with the base material, place the resin layer on the fine paper and place it on top with a 100g weight, and let it adhere to the fine paper one day later. Was visually confirmed and evaluated.

·Thermal resistance:
The thermally conductive laminate obtained above was placed on the entire surface of a disk-shaped plate (purity: 99.9%, diameter: about 12.7 mm, thickness: about 1.0 mm) made of standard aluminum, A three-layer structure was obtained by applying a pressure of about 175.5 kPa (1.80 kgf / cm ² ) by placing another standard aluminum plate on top of each other and sandwiching the resulting structure with clips.

The thickness of the test specimen obtained was measured and the thickness of the thermally conductive laminate was calculated by subtracting the known thickness of the standard aluminum plate. A micrometer (manufactured by Mitutoyo Corporation, model: M820-25VA) was used to measure the thickness of the test piece. The obtained results are shown in Tables 2 and 3. Using the test piece, the thermal resistance (cm ² · K / W) of the thermally conductive laminate was measured with a thermal resistance measuring instrument (manufactured by Netch, Xenon Flash Analyzer; LFA447 NanoFlash). The obtained thermal resistance is shown in Table 2 and Table 3.

・ Application to heat generation and heat dissipation devices:
FIG. 1 is a schematic cross-sectional view showing the structure of a heat generation / heat dissipation device. This will be described with reference to FIG. The heat conductive laminated body 1 obtained in the above Examples 1 to 3 was placed on the surface of the 2 cm × 2 cm pseudo CPU 2. The pseudo CPU 2 is mounted on the printed wiring board 3. The heat dissipating member 4 was stacked on the laminate 1 and the heat dissipating member 4 and the printed wiring board 3 were clamped by the clamp 5 to be in pressure contact. In this way, the heat generating / heat radiating device 6 in which the pseudo CPU 2 and the heat radiating member 4 were joined via the heat conductive laminate 1 was obtained.

  When power was supplied to the pseudo CPU 2, the pseudo CPU 2 generated heat and the temperature rose, but stabilized at about 100 ° C. Stable heat conduction and heat dissipation were possible for a long time of 1000 hours, and no failure of the pseudo CPU due to overheat accumulation occurred. Moreover, when removing the heat radiating member 4, damage to the pseudo CPU 2 and the printed wiring board could be prevented. Therefore, it has been confirmed that the reliability of the heat generating / dissipating device such as a semiconductor device is improved by adopting the heat conductive laminate of the present invention.

It is a conceptual diagram which shows the longitudinal cross-section of the heat_generation | fever and the heat radiating device to which the heat conductive laminated body of this invention is applied in an Example.

Explanation of symbols

1. 1. Thermally conductive laminate Pseudo CPU
3. 3. Printed wiring board 4. Heat dissipation member Clamp

Claims (9)

(A) Organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule: 100 parts by volume
(B) Thermally conductive filler: 50 to 1,000 parts by volume,
(C) Organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: The molar ratio of hydrogen atoms bonded to silicon atoms in this component / alkenyl groups in component (a) is 0.00. An amount of 5 to 5.0,
(D) platinum group metal catalyst: effective amount,
(E) reaction control agent: effective amount, and (f) silicone resin: a first cured product layer formed by curing the silicone composition 1 containing 50 to 500 parts by volume into a thin film, and the above (a) A second cured product layer obtained by forming a silicone composition 2 containing the component (f) as an essential component and having a composition different from that of the silicone composition 1 into a thin film on one side of the first cured product layer and curing it. Thermally conductive laminate with different adhesive strengths on both sides.   At room temperature, one side of a 25 mm wide sample of the laminate was applied to an aluminum plate at room temperature, and the laminate was pressed with a rubber roller having a mass of 2 kg and bonded for 10 minutes. After that, the laminate was bonded to the aluminum plate of the laminate. After bonding the other side of the laminate to the reinforcing material, one end of the laminate is gripped with the bonded reinforcing material and peeled off from the aluminum plate in a 180 ° direction at a pulling speed of 300 mm / min. When the measured force (adhesive strength) is measured on both sides of the laminate, the adhesive strength on both sides is 0.3 N / cm or more, and the difference in adhesive strength on both sides is 2 N / cm or more. The thermally conductive laminate according to claim 1. The silicone resin as component (f) contains R ¹ ₃ SiO _1/2 units (R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bond) and SiO _4/2 units. The thermal conductive laminate according to claim 1, wherein the molar ratio of R ¹ ₃ SiO _1/2 unit / SiO _4/2 unit is 0.5 to 1.5. Furthermore, as component (g),
(G-1) The following general formula (1):
R ² _a R ³ _b Si (OR ⁴ ) _4-ab (1)
Wherein R ² is independently an alkyl group having 6 to 15 carbon atoms, R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ⁴ is independently And an alkyl group having 1 to 6 carbon atoms, a is an integer of 1 to 3, b is an integer of 0 to 2, provided that a + b is an integer of 1 to 3.)
And (g-2) the following general formula (2):

(In the formula, R ⁵ is independently an alkyl group having 1 to 6 carbon atoms, and c is an integer of 5 to 100.)
The at least 1 sort (s) chosen from the group which consists of dimethylpolysiloxane by which the molecular chain piece terminal represented by this was blocked with the trialkoxy silyl group: 0.01-50 volume parts is contained in any one of Claims 1 thru | or 3 The heat conductive laminated body which concerns on. Further, as the component (h), the following general formula (3):
R ^6- (SiR ⁶ ₂ O) _d SiR ⁶ ₂ -R ⁶ (3)
(R ⁶ is a monovalent hydrocarbon group which does not contain an aliphatic unsaturated bond having 1 to 18 carbon atoms, and d is an integer of 5 to 2,000.)
The heat conductive laminate according to any one of claims 1 to 4, comprising an organopolysiloxane having a kinematic viscosity at 23 ° C represented by 10 to 100,000 mm ² / s.   The heat conductive laminate according to any one of claims 1 to 5, having a thickness of 20 to 1,000 µm. The heat conductive laminate according to any one of claims 1 to 6, wherein a thermal resistance at 25 ° C measured by a laser flash method is 10 cm ² · K / W or less. (A) Organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule: 100 parts by volume
(B) Thermally conductive filler: 50 to 1,000 parts by volume,
(C) Organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms in one molecule: The molar ratio of hydrogen atoms bonded to silicon atoms in this component / alkenyl groups in component (a) is 0.00. An amount of 5 to 5.0,
(D) platinum group metal catalyst: effective amount,
(E) Reaction control agent: Effective amount, and (f) Silicone resin: Silicone composition 1 containing 50 to 500 parts by volume is formed into a thin film on the surface of a base material subjected to surface release treatment for silicone adhesive. A first cured product layer is formed by applying and curing, and then a silicone composition 2 containing the components (a) to (f) and having a composition different from that of the silicone composition 1 is formed on the first cured product layer. A method for producing a thermally conductive laminate having different adhesive strengths on both surfaces, wherein the second cured product layer is formed by applying a thin film on the surface and curing.   The production method according to claim 8, wherein the release treatment for the silicone pressure-sensitive adhesive applied to the substrate is a treatment with a modified silicone containing a fluorine substituent in the main chain.

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