JP2009235279A - Heat-conductive molding and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-conductive molding having satisfactory handlability even in a form of thin film, fixable easily to a heat generating electronic component or a heat radiating member by itself, because having proper adhesiveness, and excellent in heat conductivity, and a manufacturing method therefor. <P>SOLUTION: This heat-conductive molding comprises a thin film-like cured object of a curable silicone composition containing (a) an organo polysiloxane having two or more of alkenyl groups, (b) a heat-conductive filler having 0.1-30 μm average particle size, having 100 ppm or less plus sieve fraction of 32 μm opening defined by JIS Z 8801-1 in terms of mass, and not containing substantially a plus sieve fraction of 45 μm opening defined by JIS Z 8801-1, (c) an organo hydrogen polysiloxane having two or more of hydrogen atoms coupled to silicon atom, (d) a platinum group metal catalyst, (e) a reaction control agent: effective amount, and (f) a silicone resin. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention particularly relates to a sheet-like thermally conductive molded body 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 for cooling the heat-generating electronic component, and It relates to the manufacturing method.

  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 it to the heat generating electronic component and the heat radiating 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 extremely 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 such a drawback, an adhesive tape that can be handled while being a thin film of a single layer and can be easily fixed to a heat-generating electronic component and a heat-dissipating member has been developed (Patent Document 1). . However, in recent years, as the amount of heat generated by the heat generating member increases more and more, the heat dissipation effect has become insufficient with ordinary adhesive tapes. In order to improve the heat dissipation performance, there is one method of highly filling the heat conductive filler. However, when the heat conductive filler is highly filled, the pressure-sensitive adhesive tape itself tends to become brittle and the handleability is lowered, so there is a limit to increasing the filling degree. Another method is to reduce the thickness of the adhesive tape because the thermal resistance is proportional to the thickness of the heat dissipation material. In practice, this method can also effectively reduce the thermal resistance. Therefore, the heat dissipation effect cannot be enhanced.

Patent Document 2 is a heat conductive silicone grease, which contains indium powder as a heat conductive filler in an amount of more than 90% by mass and 100% by mass or less, and in addition, the average particle size is 0.1 to 20 μm, JIS Z 8801-1 describes a composition in which the sieve top fraction with a sieve opening of 32 μm is 50 ppm or less on a mass basis, and the sieve top fraction with a sieve opening of 45 μm specified in the same standard is substantially 0 ppm. Has been. The composition does not disclose a thermally conductive sheet.
Patent documents 3-6 are mentioned as what discloses the prior art relevant to the present invention.

Japanese Patent Laid-Open No. 2002-030212 JP 2007-051227 A 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 even in a thin film and has an appropriate adhesiveness, so that it can be easily fixed to a heat-generating electronic component or a heat-dissipating member by itself, and a heat-conductive molded article having excellent heat conductivity and its It is to provide a manufacturing method.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the reason why the attempt to reduce the thermal resistance by making the adhesive tape thin in the above method is not successful is the heat conductive filler. Coarse grains are usually mixed in the inorganic powder to be used. For this reason, when the tape is thinned, the surface of the coarse grains is exposed and the contact between the heat generating member and the heat radiating member is hindered. Therefore, the present invention has found that this problem can be solved by employing a thermally conductive filler having a specific particle size distribution.

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 curable silicone composition containing 50 to 500 parts by volume, and the heat conductive filler of component (b) has an average particle size of 0. .1 to 30 μm, the fraction on the sieve having an opening of 32 μm as defined in JIS Z 8801-1 is 100 ppm or less on a mass basis, and the fraction on the sieve having an opening of 45 μm as defined in the same standard is substantially Provided is a thermally conductive molded body comprising a thin film-like cured product of a silicone composition which does not contain.

  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 molded object of this invention.

The silicone resin as component (f) is composed of 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. 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 is further used as a 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

-The silicone composition further comprises the following average composition 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 that 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 molded object is 100 micrometers or less in thickness, especially 20-100 micrometers.

-It is preferable that the said heat conductive molded object is 1.5 cm < ² > * K / W or less in 25 degreeC thermal resistance measured by the laser flash method.

The present invention secondly,
(A) Organopolysiloxane having an alkenyl group: 100 parts by volume,
(B) Thermally conductive filler: 50 to 1,000 parts by volume,
(C) Organohydrogenpolysiloxane: an amount of 0.5 to 5.0 in terms of a molar ratio of hydrogen atoms directly bonded to silicon atoms in component (c) and alkenyl groups in component (a),
(D) platinum group metal catalyst: effective amount,
(E) Reaction control agent: Effective amount, and (f) Silicone resin: A curable silicone composition containing 50 to 500 parts by volume, and the heat conductive filler of component (b) has an average particle size of 0. .1 to 30 μm, the fraction on the sieve having an opening of 32 μm as defined in JIS Z 8801-1 is 100 ppm or less on a mass basis, and the fraction on the sieve having an opening of 45 μm as defined in the same standard is substantially Production of a thermally conductive molded article characterized in that a silicone composition not containing a silicone composition is applied to the surface of a substrate subjected to surface release treatment for a silicone adhesive and cured to obtain a thin film cured product Provide a method.

  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.

  Since the heat conductive molded body of the present invention has moderate surface tackiness, it can be easily fixed by sticking to a heat-generating electronic component or a heat radiating member, and easily peelable from an adherend as needed. Since it can be used, it is easy to handle. 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 molded article of the present invention is useful as a heat conductive sheet.

  Hereinafter, the present invention will be described in detail.

The heat conductive molded object of this invention is formed from the composition which contains the said (a)-(f) component as an essential component. 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, etc. , 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 and bromine, cyano groups For example, chloromethyl group, 2-bromoethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, chlorophenyl group, fluorophenyl group, cyanoethyl group, 3,3,4, Examples include 4,5,5,6,6,6-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 group, 3,3,3-trifluoropropyl group, cyanoethyl group and other unsubstituted or substituted alkyl groups having 1 to 3 carbon atoms, and phenyl group, chlorophenyl group, fluoro An unsubstituted or substituted phenyl group such as a phenyl 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 size of usually 0.1 to 30 μm, preferably 0.5 to 20 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.

  The heat conductive filler of component (b) has a sieve top fraction with an opening of 32 μm and a mass basis of 50 ppm or less, preferably 30 ppm or less. When the composition on the sieve having an opening of 32 μm exceeds 50 ppm in the composition before curing, the particle surface of the thermally conductive filler is exposed on the surface of the obtained thin film-like molded body. For this reason, the thermal resistance of the molded body is significantly increased. Further, even if the fraction on the sieve having a mesh size of 32 μm is 50 ppm or less, even if one large coarse particle is present in the composition, even in that case, the contact between the cured product on the thin film and the adherend As a result, the desired heat dissipation effect cannot be obtained. Therefore, in order to obtain a desired heat dissipation effect, it is necessary that the fraction on the sieve having a mesh size of 45 μm does not substantially exist. Here, “substantially non-existent” means that 50 g of the heat conductive composition is placed in a 200 ml plastic bottle together with 100 g of toluene, capped and shaken until the heat conductive composition is completely dispersed. Then, the dispersion is poured into a sieve (standard sieve: JIS Z 8801) having an opening of 45 μm, thoroughly washed with toluene for washing, and the sieve is put into a dryer and dried. After drying, the coarse particles on the test sieve are transferred to the medicine wrapping paper and visually observed, which means that the coarse particles of the fraction on the sieve having an opening of 45 μm are not visually recognized.

  In order to remove unnecessary coarse particles from the composition before curing, there is a method of directly filtering the composition through a sieve. However, a material containing a highly thermally conductive filler such as the composition is used. It is practically difficult to filter, and it is preferable to remove coarse particles from the thermally conductive filler before blending into the composition.

  A manufacturer that manufactures a filler such as a heat conductive filler measures the particle size distribution and puts a value on an inspection table or the like, but coarse particles with a small absolute amount cannot generally be detected by a particle size distribution measuring device. Therefore, even if the same material and the same average particle diameter are used, there is a large difference in heat dissipation characteristics depending on whether or not coarse particles are removed. It is particularly important to control the amount of coarse particles of the heat conductive filler at the time when the heat generation of the heat-generating electronic parts is very large.

  There are several ways to remove coarse particles from these thermally conductive fillers. Generally, there are airflow classification, mesh classification, etc. As long as coarse particles are removed to a high degree, the classification of the thermally conductive filler is not limited, but the thermally conductive filler used in the present invention is classified into mesh classification. It is preferable to multiply. Although air classification can remove coarse particles with a considerable probability, it is still more difficult to remove, and mesh classification has a maximum particle size of substantially 45 μm, for example, if a sieve product having an opening of 45 μm is used. A thermally conductive filler is obtained.

  In the present invention, in order to measure the coarse particle mass in the thermally conductive composition before curing, for example, it is dissolved in a solvent such as toluene, and the resulting solution is sieved with a sieve having an opening of 45 μm as defined in JIS Z8801, and After passing through a sieve having an opening of 32 μm and thoroughly washing, the particles remaining on the sieve having an opening of 45 μm are visually observed. Coarse particles remaining on the sieve having an opening of 32 μm are collected on a medicine wrapping paper after drying, What is necessary is just to measure the mass.

[(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 thin-film shaped article 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.), etc.), platinum modified with chloroplatinic acid and chloroplatinate, alcohol-modified chloroplatinic acid, chloroplatinic acid and olefin complex, platinum black , Platinum group metals such as palladium supported on alumina, silica, carbon, etc., rhodium-olefin complex, chlorotris (triphenylphosphine) rhodium (Wilki Nson catalyst), platinum chloride, chloroplatinic acid, or a complex of 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 the hydrogen atoms bonded to the carbon atoms of these groups , Groups substituted by halogen atoms such as fluorine, chlorine and bromine, cyano groups, etc. Tyl 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 , 6-nonafluorohexyl group and the like having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, among them, preferably methyl group, ethyl group, propyl group, chloromethyl group, C1-C3 unsubstituted or substituted alkyl group such as bromoethyl group, 3,3,3-trifluoropropyl group, cyanoethyl group, and unsubstituted or substituted phenyl group such as phenyl group, chlorophenyl group, fluorophenyl group It is a group. 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 it 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 used for this invention, components other than said (a)-(f) component can be added as needed in the range which does not impair the objective of this invention. 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. The component has a function as a wetter.

(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 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, it is preferable that the compounding quantity of (g) component is 0.01-50 volume parts with respect to 100 volume parts of (a) component.

(H) Organopolysiloxane:

In the composition of the present invention, the following average composition formula (3):
R ^6- (SiR ⁶ ₂ O) _d SiR ⁶ ₂ -R ⁶ (3)
(R ⁶ is a monovalent hydrocarbon group that 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 a number from 1.8 to 2.2, and particularly preferably a number from 1.9 to 2.1.

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 molded body]
It is possible to obtain the thin-film thermally conductive molded body of the present invention by uniformly mixing the required components among the above-mentioned components, forming the mixture into a thin film on a base material, and curing by heating. is there.

  The thickness of the molded body on a thin film of the present invention is preferably 100 μm or less, particularly 20 to 100 μm, and more preferably 30 to 50 μm from the viewpoints of handleability, obtained adhesiveness and thermal conductivity.

  A composition of the present invention is prepared by uniformly mixing the required components. The composition is applied and formed on a substrate and cured by heating to form a thin film-like cured product. In this way, the heat conductive molded object of this invention can be obtained. When applying and molding the composition on a substrate, a solvent such as toluene can be added to adjust the viscosity of the composition.

〔Characteristic〕
·Thermal resistance:
The heat conductive molded body of the present invention preferably has a thermal resistance at 25 ° C. measured by a laser flash method of 1.5 cm ² · K / W or less, particularly 1.0 cm ² · K / W or less. It is preferable. When the thermal resistance is within this range, even when the molded body of the present invention is applied to a heating element having a large calorific value, heat generated from the heating element can be efficiently transmitted to the heat radiating member. In addition, the measurement of the thermal resistance by the laser flash method can be performed in accordance with ASTM E 1461.

[Method for producing thermally conductive molded body]
The thermally conductive molded body of the present invention is, for example, a group obtained by subjecting a silicone composition containing a predetermined amount of each of the components (a) to (f) to a surface release treatment for a silicone adhesive. It can be manufactured by applying a thin film on the surface of the material and curing it to obtain a thin film cured product.

In the above method, the blending order of each component when preparing the composition 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, a curing agent prepared by mixing the component (c) and the component (e) is prepared.
(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 on which the silicone composition 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 molded body after curing can be transported and scaled by sticking the same release treatment film as the base film as a protective separator film on the surface opposite to the base side of the molded body. Handling such as cutting can be facilitated. In this case, 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 a light weight to the peeling force from the molded body of the base film and the separator film. .

  The heat conductive molded body 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.

  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, a sieved product having an opening of 32 μm classified by a sieve (true specific gravity 3.98).
(B-2) Alumina powder having an average particle diameter of 20.6 μm, a sieved product having a mesh size of 32 μm classified by a sieve (true specific gravity 3.98).
(B-3) Zinc oxide powder having an average particle diameter of 0.5 μm, and a sieved product having an opening of 32 μm classified by airflow classification (true specific gravity 5.67).
(B-4) Alumina powder having an average particle diameter of 20.6 μm, not subjected to classification treatment (true specific gravity 3.98).
(B-5) Alumina powder having an average particle diameter of 1.0 μm, and a sieved product having a mesh size of 32 μm classified by a sieve (true specific gravity 3.98).
(B-6) Alumina powder having an average particle size of 5.3 μm, not subjected to classification treatment (true specific gravity 3.98).

<(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) 1 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).

<(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

[Examples 1 to 3, Comparative Examples 1 to 5]
<Preparation of thermal conductive composition>
The components described in Tables 1 and 2 were blended in the following amounts in the blending amounts (parts by volume or ppm based on mass) listed in the same table to prepare the compositions of the respective examples.

  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.

<Visual observation of particles on the sieve with an opening of 45 μm>
50 g of the composition was placed in a 200 ml plastic bottle with 100 g of toluene, stoppered and shaken until the composition was well dispersed. After the dispersion, the dispersion was poured into a sieve (standard sieve: JIS Z 8801) having an opening of 45 μm, thoroughly washed with toluene for washing, and the sieve was put in a dryer and dried. After drying, the coarse particles on the test sieve were transferred to the medicine wrapping paper, visually observed, and evaluated according to the following criteria. The evaluation results are shown in Tables 1 and 2.

..Criteria:
○: Coarse particles of the sieved portion having an opening of 45 μm are not visually recognized.

    X: At least one coarse particle of the fraction on the sieve having an opening of 45 μm was visually observed.

<Visual observation of particles on the sieve having an opening of 32 μm>
50 g of the composition in which coarse particles were not observed by visual observation of the particles on the sieve having a mesh opening of 45 μm was placed in a 200 ml plastic bottle together with 100 g of toluene, and the stopper was shaken until the composition was sufficiently dispersed. That ’s it. After the dispersion, the dispersion was poured into a test sieve (standard sieve: JIS Z 8801) having a mesh size of 32 μm, washed thoroughly with toluene for washing, and the sieve was put in a dryer and dried. After drying, the coarse particles on the test sieve were transferred to a medicine wrapping paper, and the mass was measured to calculate how many ppm with respect to the composition. The evaluation results are shown in Tables 1 and 2.

<Molding of heat conductive cured product>
After the composition was uniformly mixed, it was applied to a substrate under the conditions described in Tables 1 and 2 and cured to obtain a thin-film thermally conductive molded body.

  About the obtained heat conductive molded object, the following method evaluated the bleeding property, the peelability from a base material, the handleability after peeling, and thermal resistance. The results are shown in Tables 1 and 2.

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

・ 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 molded body 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, Another standard aluminum plate was stacked on top of each other, and the resulting structure was sandwiched between clips to apply a pressure of about 175.5 kPa (1.80 kgf / cm ² ) to obtain a thin-film shaped body.

The thickness of the obtained test piece was measured, and the thickness of the thermally conductive molded body 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 1 and 2. Using the test piece, the thermal resistance (cm ² · K / W) of the thermally conductive molded body was measured with a thermal resistance measuring instrument (manufactured by Netch Co., Ltd., xenon flash analyzer; LFA447 NanoFlash). The obtained thermal resistance is shown in Table 1 and Table 2.

・ 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 thermally conductive molded 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 radiating member 4 was stacked on the molded body 1, and the heat radiating member 4 and the printed wiring board 3 were clamped by the clamp 5 to be pressed. In this way, a heat generating / heat radiating device 6 in which the pseudo CPU 2 and the heat radiating member 4 were joined via the heat conductive molded body 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 1,000 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 could be prevented. Therefore, it was confirmed that the reliability of the heat generating and heat radiating device such as a semiconductor device was improved by employing the heat conductive molded body of the present invention.

・ Notes on Table 1 and Table 2:
<< Note 1 >>: The numerical value in parentheses in the table is the volume part of resin of (f) component relative to the capacity of component (a) << Note 2 >>: Component (d) and (e) in the table In this row, the numerical value indicates the amount of the component (D-1) and the component (E-1) in parts by mass with respect to 100 parts by mass of the component (a). The numerical values in parentheses are the net concentration (ppm) of platinum atoms in component (D-1) relative to the mass of component (a) and 1-ethynyl contained in component (E-1) relative to the mass of component (a) It is the net concentration (ppm) of -1-cyclohexanol.
<< 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).

It is a conceptual diagram which shows the longitudinal cross-section of the heat_generation | fever and the thermal radiation apparatus to which the heat conductive molded object of this invention is applied in an Example.

Explanation of symbols

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

Claims (8)

(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 curable silicone composition containing 50 to 500 parts by volume. The thermal conductive filler of the component (b) has an average particle size of 0. .1 to 30 μm, the fraction on the sieve having an opening of 32 μm as defined in JIS Z 8801-1 is 100 ppm or less on a mass basis, and the fraction on the sieve having an opening of 45 μm as defined in the same standard is substantially A thermally conductive molded article comprising a thin film-like cured product of a silicone composition which does not contain. The silicone resin as component (f) contains 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. The thermally conductive molded article according to claim 1, wherein the molar ratio of R ¹ ₃ SiO _1/2 units / SiO _4/2 units 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 the 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. The heat conductive molded object which concerns on. Further, as the component (h), the following average composition formula (3):
R ^6- (SiR ⁶ ₂ O) _d SiR ⁶ ₂ -R ⁶ (3)
(R ⁶ is a monovalent hydrocarbon group that 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 molded object according to any one of claims 1 to 3, comprising an organopolysiloxane having a kinematic viscosity at 23 ° C represented by 10 to 100,000 mm ² / s.   The thermally conductive molded article according to any one of claims 1 to 4, having a thickness of 100 µm or less. The heat conductive molded body according to any one of claims 1 to 5, wherein a thermal resistance at 25 ° C measured by a laser flash method is 1.5 cm ² · K / W or less. (A) Organopolysiloxane having an alkenyl group: 100 parts by volume,
(B) Thermally conductive filler: 50 to 1,000 parts by volume,
(C) Organohydrogenpolysiloxane: an amount of 0.5 to 5.0 in terms of a molar ratio of hydrogen atoms directly bonded to silicon atoms in component (c) and alkenyl groups in component (a),
(D) platinum group metal catalyst: effective amount,
(E) Reaction control agent: Effective amount, and (f) Silicone resin: A curable silicone composition containing 50 to 500 parts by volume, and the heat conductive filler of component (b) has an average particle size of 0. .1 to 30 μm, the fraction on the sieve having an opening of 32 μm as defined in JIS Z 8801-1 is 100 ppm or less on a mass basis, and the fraction on the sieve having an opening of 45 μm as defined in the same standard is substantially Production of a thermally conductive molded article characterized in that a silicone composition not containing a silicone composition is applied to the surface of a substrate subjected to surface release treatment for a silicone adhesive and cured to obtain a thin film cured product Method.   The production method according to claim 7, 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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