JP2011068720A - Heat-conductive pressure-sensitive adhesive laminated sheet and electronic part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-conductive pressure-sensitive adhesive laminated sheet having heat conductivity, insulation property and flexibility; and to provide an electronic part including the same. <P>SOLUTION: The heat-conductive pressure-sensitive adhesive laminated sheet (F) includes a layer A comprising a heat-conductive pressure-sensitive adhesive composition (E1) containing at least one polymer (S1) selected from the group consisting of a rubber, an elastomer and a resin; a layer B1 laminated on one side of the layer A, the layer B1 comprising a heat-conductive pressure-sensitive adhesive composition (E2) containing at least one polymer (S2) selected from the group consisting of a rubber, an elastomer and a resin; and a layer B2 laminated on the other side of the layer A, the layer B2 comprising a heat-conductive pressure-sensitive adhesive composition (E3) containing at least one polymer (S3) selected from the group consisting of a rubber, an elastomer and a resin. The electronic part includes the sheet. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a heat conductive pressure-sensitive adhesive laminate sheet and an electronic component including the sheet.

  In recent years, electronic components such as plasma display panels (PDP), integrated circuit (IC) chips, and the like have increased in heat generation as their performance has increased. As a result, there is a need to take measures against functional failures due to temperature rise. In general, a method of diffusing and radiating heat is adopted by attaching a heat sink such as a metal heat sink, heat radiating plate, or heat radiating fin to a heat generating body such as an electronic component. In order to efficiently conduct heat conduction from the heating element to the heat radiating body, various heat conduction sheets are used, but in general, a heat conductive pressure-sensitive adhesive sheet is used for fixing the heating element and the heat radiating element. is needed.

  Such a heat conductive pressure-sensitive adhesive sheet may be required to have other performance (insulation, flexibility, etc.) depending on the application in addition to the heat conductivity. In order to provide a sheet-like member such as a heat conductive pressure-sensitive adhesive sheet with a plurality of performances, it is conceivable to form a laminated sheet by laminating layers having different performances. For example, Patent Document 1 discloses a technique related to a laminated sheet obtained by laminating a resin layer or a metal layer on an aromatic polyamide film, and according to such a laminated sheet, a highly reliable laminated sheet having insulating properties and the like You can do that.

JP 2002-144510 A

  As described above, the heat conductive pressure-sensitive adhesive sheet is required to have performances other than heat conductivity depending on applications. Specifically, in addition to thermal conductivity, flexibility is required, and in particular, insulation has been required to cope with applications that are directly attached to LED light sources and the like. However, the conventional techniques disclosed so far, including the technique disclosed in Patent Document 1, provide a thermally conductive pressure-sensitive adhesive sheet having thermal conductivity, insulation and flexibility. It was difficult. For example, in order to achieve both thermal conductivity and insulating properties, a laminated sheet composed of a metal layer and a resin layer can be considered. However, if a metal layer is used, flexibility is impaired, so that flexibility is required. It is not suitable. Further, since there is a difference in flexibility between the metal layer and the resin layer, there has been a problem that when the metal layer is bent, the metal layer is easily peeled off at the interface. Furthermore, there is a problem that it is difficult to increase the thickness of the metal layer in terms of metal rigidity and high specific gravity.

  Then, an object of this invention is to provide the heat conductive pressure-sensitive-adhesive laminated sheet provided with heat conductivity, insulation, and a softness | flexibility, and an electronic component provided with this sheet | seat.

  The present inventors have found that the above problem can be solved by sandwiching a layer having a high thermal conductivity made of a predetermined material with an insulating layer made of a predetermined material, and to complete the present invention. It came.

  Thus, according to the first aspect of the present invention, the A layer composed of the heat conductive pressure-sensitive adhesive composition (E1) containing at least one polymer (S1) selected from the group consisting of rubber, elastomer and resin; A B1 layer comprising a thermally conductive pressure-sensitive adhesive composition (E2) comprising at least one polymer (S2) selected from the group consisting of rubber, elastomer and resin, laminated on one surface side of the layer; A layer B2 made of a heat conductive pressure-sensitive adhesive composition (E3) containing at least one polymer (S3) selected from the group consisting of rubber, elastomer and resin, laminated on the other surface side of the layer; A heat conductive pressure-sensitive adhesive laminate sheet (F) is provided.

  In the heat conductive pressure-sensitive adhesive laminated sheet (F) of the first aspect of the present invention, the expanded graphite powder (B) in which the A layer is 30 to 800 parts by mass with respect to 100 parts by mass of the polymer (S1). It is preferable to contain. In the present invention, it is possible to contain a large amount of expanded graphite powder (B) in the A layer, and according to the increase in the content of expanded graphite powder (B), the heat conductive pressure-sensitive adhesive laminate sheet (F) ) Thermal conductivity can be improved.

  In the heat conductive pressure-sensitive adhesive laminate sheet (F) of the first aspect of the present invention, the thicknesses of the B1 layer and the B2 layer are preferably 1 μm or more and 1500 μm or less. If the B1 layer and the B2 layer are too thin, it is difficult to uniformly laminate the A layer without a gap, and it becomes difficult to obtain the effect (insulation improvement) caused by sandwiching the A layer between the B1 layer and the B2 layer. If the B1 layer and the B2 layer are too thick, the thermal conductivity of the heat conductive pressure-sensitive adhesive laminated sheet (F) tends to be lowered.

  In the heat conductive pressure-sensitive adhesive laminated sheet (F) of the first invention, the polymer (S1) is a (meth) acrylic acid ester polymer (A1), and the polymer (S2) is (meth) acrylic acid. It is an ester polymer (A2), and the polymer (S3) is preferably a (meth) acrylic acid ester polymer (A3). In the present invention, “(meth) acryl” means “acryl and / or methacryl”. By making the polymer (S1) a (meth) acrylic acid ester polymer (A1), it is easy to impart adhesion and flexibility to the A layer, and the polymer (S2) is converted into a (meth) acrylic acid ester polymer (A2). ), It is easy to give adhesion and flexibility to the B1 layer, and by making the polymer (S3) a (meth) acrylate polymer (A3), the adhesion and flexibility are given to the B2 layer. Cheap.

  In the thermally conductive pressure-sensitive adhesive laminated sheet (F) of the first invention, the (meth) acrylic acid ester polymer (A1) is in the presence of the (meth) acrylic acid ester polymer (AP1). It is obtained by polymerizing the acid ester monomer (α1), and the (meth) acrylic acid ester polymer (A2) is (meth) acrylic in the presence of the (meth) acrylic acid ester polymer (AP2). It is obtained by polymerizing the acid ester monomer (α2), and the (meth) acrylic acid ester polymer (A3) is (meth) acrylic in the presence of the (meth) acrylic acid ester polymer (AP3). It is preferably obtained by polymerizing the acid ester monomer (α3). The (meth) acrylic acid ester polymer (A1) is obtained by polymerizing the (meth) acrylic acid ester monomer (α1) in the presence of the (meth) acrylic acid ester polymer (AP1). Thus, the moldability of the A layer can be improved, and the (meth) acrylate polymer (A2) is converted into a (meth) acrylate ester in the presence of the (meth) acrylate polymer (AP2). The moldability of the B1 layer can be improved by being obtained by polymerizing the body (α2), and the (meth) acrylate polymer (A3) is converted into a (meth) acrylate polymer ( By forming the (meth) acrylate monomer (α3) in the presence of AP3), the moldability of the B2 layer can be improved. .

  Moreover, according to 2nd this invention, the electronic component provided with the heat conductive pressure-sensitive-adhesive laminated sheet (F) of 1st this invention is provided.

  In the second aspect of the present invention, as an electronic component, an electroluminescence (EL), a device having a light emitting diode (LED) light source, an automobile power device, a fuel cell, a solar cell, a battery, a mobile phone, a personal digital assistant (PDA), A notebook computer, a liquid crystal, a surface conduction electron-emitting device display (SED), a plasma display panel (PDP), or an integrated circuit (IC) is preferable.

  ADVANTAGE OF THE INVENTION According to this invention, the heat conductive pressure-sensitive-adhesive laminated sheet provided with heat conductivity, insulation, and a softness | flexibility, and an electronic component provided with this sheet can be provided.

1. Thermally conductive pressure-sensitive adhesive laminate sheet (F)
The heat conductive pressure-sensitive adhesive laminated sheet (F) of the present invention comprises a heat conductive pressure-sensitive adhesive composition (E1) containing at least one polymer (S1) selected from the group consisting of rubber, elastomer and resin. A layer and a heat conductive pressure sensitive adhesive composition (E2) containing at least one polymer (S2) selected from the group consisting of rubber, elastomer and resin, laminated on one surface side of the A layer B1 layer and the heat conductive pressure sensitive adhesive composition (E3) containing at least one polymer (S3) selected from the group consisting of rubber, elastomer and resin, laminated on the other surface side of the A layer B2 layer.

1.1. A layer A layer consists of a heat conductive pressure sensitive adhesive composition (E1) containing at least 1 type of polymer (S1) chosen from the group which consists of rubber | gum, an elastomer, and resin.

<Polymer (S1)>
As what comprises a polymer (S1), at least 1 type arbitrarily selected from rubber | gum, an elastomer, and resin can be mentioned. And in order to equip A layer with adhesiveness and / or adhesiveness, it is preferable to make adhesiveness and / or adhesiveness provide a polymer (S1). In order to provide the polymer (S1) with adhesiveness and / or tackiness, the rubber, elastomer and resin are preferably selected from those having adhesiveness and / or tackiness. However, an adhesive agent can be used in combination with rubber, elastomer and resin having no adhesiveness and / or tackiness.

  Specific examples of rubbers, elastomers and resins that can be used in the present invention are listed below.

  Conjugated diene polymers such as natural rubber, polybutadiene rubber, polyisoprene rubber; butyl rubber; styrene-butadiene random copolymer, styrene-isoprene random copolymer, styrene-butadiene-isoprene random copolymer, styrene-butadiene block copolymer Polymer, styrene-isoprene block copolymer, styrene-butadiene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, etc., aromatic vinyl-conjugated diene copolymer; styrene-butadiene copolymer Hydrogenated aromatic vinyl-conjugated diene copolymer, such as hydrogenated product; vinyl cyanide compound-conjugated diene copolymer, such as acrylonitrile-butadiene copolymer rubber, acrylonitrile-isoprene copolymer rubber; acrylonitrile- Hydrogenates of vinyl cyanide compounds-conjugated diene copolymers, such as hydrogenates of tadiene copolymers; vinyl cyanides-aromatic vinyl-conjugated diene copolymers; vinyl cyanide compounds-aromatic vinyl-conjugated Hydrogenated diene copolymer; mixture of vinyl cyanide compound-conjugated diene copolymer and poly (vinyl halide); polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polymethyl methacrylate, polyacrylic Ethyl acetate, polyethyl methacrylate, poly (n-butyl acrylate), poly (n-butyl methacrylate), poly (2-ethylhexyl acrylate), poly (2-ethylhexyl methacrylate), poly [acrylic acid- ( N-butyl acrylate)], poly [acrylic acid- (2-ethylhexyl acrylate)], poly [acrylic acid Acid- (n-butyl acrylate)-(2-ethylhexyl acrylate)], poly [methacrylic acid- (n-butyl acrylate)], poly [methacrylic acid- (2-ethylhexyl acrylate)], poly [methacryl Acid- (n-butyl acrylate)-(2-ethylhexyl acrylate)], poly [acrylic acid-methacrylic acid- (n-butyl acrylate)], poly [acrylic acid-methacrylic acid- (2-ethylhexyl acrylate) )], Poly [acrylic acid-methacrylic acid- (n-butyl acrylate)-(2-ethylhexyl acrylate)], poly (stearyl acrylate), poly (stearyl methacrylate), (meth) acrylic polymers ("(meta ) Acrylic ”means“ acrylic and / or methacrylic. ”The same applies hereinafter.); Polyepichlorohydride Polyepihalohydrin rubber such as polyethylene rubber and polyepibromohydrin rubber; Polyalkylene oxide such as polyethylene oxide and polypropylene oxide; Ethylene-propylene-diene copolymer (EPDM); Silicone rubber; Silicone resin; Fluoro rubber; Fluoro resin; Polyethylene; ethylene-α-olefin copolymer such as ethylene-propylene copolymer and ethylene-butene copolymer; α-olefin polymer such as polypropylene, poly-1-butene and poly-1-octene; poly Polyvinyl halide resins such as polyvinyl chloride resins and polyvinyl bromide resins; Polyvinylidene chloride resins such as polyvinylidene chloride resins and polyvinylidene bromide resins; Epoxy resins; Phenol resins; Polyphenylene ether resins; Nylon-6 , Nylon-6,6, nylon-6,12, etc., polyamide; polyurethane; polyester; polyvinyl acetate; poly (ethylene-vinyl alcohol);

  Among the specific examples of the rubber, elastomer and resin described above, styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, polyacrylate, poly (n-butyl acrylate), poly (acrylic acid 2 -Ethylhexyl), poly [acrylic acid- (n-butyl acrylate)], poly [acrylic acid- (2-ethylhexyl acrylate)], poly [acrylic acid- (n-butyl acrylate)-(acrylic acid 2- Ethyl hexyl)], poly [methacrylic acid- (n-butyl acrylate)], poly [methacrylic acid- (2-ethylhexyl acrylate)], poly [methacrylic acid- (n-butyl acrylate)-(acrylic acid 2- Ethylhexyl)], poly [acrylic acid-methacrylic acid- (n-butyl acrylate)], poly [acrylic acid] Acid - methacrylic acid - (2-ethylhexyl acrylate)], poly [acrylic acid - methacrylic acid - (n-butyl acrylate) - (2-ethylhexyl acrylate)] is, adhesion, preferred because of its excellent adhesiveness.

  More preferably, poly (n-butyl acrylate), poly (2-ethylhexyl acrylate), poly [acrylic acid- (n-butyl acrylate)], poly [acrylic acid- (2-ethylhexyl acrylate)], Poly [acrylic acid- (n-butyl acrylate)-(2-ethylhexyl acrylate)], poly [methacrylic acid- (n-butyl acrylate)], poly [methacrylic acid- (2-ethylhexyl acrylate)], Poly [methacrylic acid- (n-butyl acrylate)-(2-ethylhexyl acrylate)], poly [acrylic acid-methacrylic acid- (n-butyl acrylate)], poly [acrylic acid-methacrylic acid- (acrylic acid) 2-ethylhexyl)], poly [acrylic acid-methacrylic acid- (n-butyl acrylate)-(2-ethylhexyl acrylate) ], And the like.

  More preferable examples include poly [acrylic acid- (2-ethylhexyl acrylate)], poly [methacrylic acid- (2-ethylhexyl acrylate)], and poly [acrylic acid-methacrylic acid- (2-ethylhexyl acrylate)]. It is done.

  The said substance quoted as a specific example of rubber | gum, an elastomer, and resin may be used individually by 1 type, and may use 2 or more types together.

  Various known materials can be used as the tackifier imparted to the polymer (S1) as desired. For example, petroleum resin, terpene resin, phenol resin and rosin resin can be mentioned, and among these, petroleum resin is preferable. These may be used individually by 1 type and may use 2 or more types together.

  Specific examples of petroleum resins include C5 petroleum resins obtained from pentene, pentadiene, isoprene, etc .; C9 petroleum resins obtained from indene, methylindene, vinyltoluene, styrene, α-methylstyrene, β-methylstyrene, etc .; C5-C9 copolymer petroleum resin obtained from monomer; petroleum resin obtained from cyclopentadiene, dicyclopentadiene; hydride of these petroleum resins; maleic anhydride, maleic acid, fumaric acid, (meth) of these petroleum resins And modified petroleum resins modified with acrylic acid, phenol, and the like.

  Examples of terpene resins include α-pinene resins, β-pinene resins, and aromatic-modified terpene resins obtained by copolymerizing terpenes such as α-pinene and β-pinene and aromatic monomers such as styrene. .

  As the phenol resin, a condensate of phenols and formaldehyde can be used. Examples of the phenols include phenol, m-cresol, 3,5-xylenol, p-alkylphenol, resorcin, and the like. These phenols and formaldehyde are subjected to a condensation reaction with an acid catalyst or an acid catalyst. The novolak obtained by this can be illustrated. Moreover, the rosin phenol resin etc. which are obtained by adding phenol to an rosin with an acid catalyst and heat-polymerizing can also be illustrated.

  Examples of rosin resins include gum rosin, wood rosin or tall oil rosin, stabilized rosin or polymerized rosin disproportionated or hydrogenated using the rosin, maleic anhydride, maleic acid, fumaric acid, (meth) acrylic acid, Examples thereof include modified rosin modified with phenol and the like, and esterified products thereof.

  The alcohol used for esterification to obtain the esterified product is preferably a polyhydric alcohol, and examples thereof include dihydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol and neopentyl glycol, glycerin, trimethylolethane, Examples include trihydric alcohols such as trimethylolpropane, tetrahydric alcohols such as pentaerythritol and diglycerin, and hexahydric alcohols such as dipentaerythritol. These may be used alone or in combination of two or more. You may use together.

  The softening point of these adhesiveness-imparting agents is not particularly limited, and liquids at room temperature can be appropriately selected from those having a high softening point of 200 ° C. or lower.

((Meth) acrylic acid ester polymer (A1))
As the polymer (S1), a (meth) acrylic acid ester polymer (A1) is preferable. The (meth) acrylate polymer (A1) is obtained by polymerizing the (meth) acrylate monomer (α1) in the presence of the (meth) acrylate polymer (AP1). Is particularly preferred. When the heat conductive pressure-sensitive adhesive composition (E1) is formed into an A layer, the heat conductive pressure-sensitive adhesive composition (E1) is formed into a sheet shape or after being formed into a sheet shape, The (meth) acrylic acid ester monomer (α1) in the heat conductive pressure-sensitive adhesive composition (E1) is polymerized and converted into a (meth) acrylic acid ester polymer. The (meth) acrylic acid ester polymer (A1) is obtained by mixing and / or partially bonding with the component (AP1). The (meth) acrylic acid ester polymer (A1) corresponds to all the (meth) acrylic acid ester polymer components in the A layer, and comprehensively includes all the (meth) acrylic acid ester polymer components in the A layer. It is a concept to represent.

((Meth) acrylic acid ester polymer (AP1))
Hereinafter, the (meth) acrylic acid ester polymer (AP1) will be described in detail.

  The (meth) acrylic acid ester polymer (AP1) is not particularly limited, but the unit (a1) of the (meth) acrylic acid ester monomer that forms a homopolymer having a glass transition temperature of −20 ° C. or lower, and It is preferable to contain a monomer unit (a2) having an organic acid group.

  The (meth) acrylate monomer (a1m) that gives the unit (a1) of the (meth) acrylate monomer that forms a homopolymer having a glass transition temperature of −20 ° C. or lower is not particularly limited. However, for example, ethyl acrylate (the glass transition temperature of the homopolymer is -24 ° C), propyl acrylate (-37 ° C), butyl acrylate (-54 ° C), sec-butyl acrylate (same as above) -22 ° C), heptyl acrylate (-60 ° C), hexyl acrylate (-61 ° C), octyl acrylate (-65 ° C), 2-ethylhexyl acrylate (-50 ° C), acrylic acid 2 -Methoxyethyl (same -50 ° C), 3-methoxypropyl acrylate (same -75 ° C), 3-methoxybutyl acrylate (same -56 ° C), 2-ethoxymethyl acrylate (same -50) ), Octyl methacrylate (same -25 ° C.), and the like decyl methacrylate (same -49 ° C.).

  These (meth) acrylic acid ester monomers (a1m) may be used individually by 1 type, and may use 2 or more types together.

  In these (meth) acrylate monomers (a1m), the monomer unit (a1) derived therefrom is preferably 80% by mass or more and 99.9% by mass in the (meth) acrylate polymer (AP1). % Or less, more preferably 85% by mass or more and 99.5% by mass or less. When the amount of the (meth) acrylic acid ester monomer (a1m) is within the above range, the A layer obtained therefrom is excellent in pressure-sensitive adhesiveness around room temperature.

  The monomer (a2m) that gives the monomer unit (a2) having an organic acid group is not particularly limited, and representative examples thereof include organic acid groups such as a carboxyl group, an acid anhydride group, and a sulfonic acid group. In addition to these, monomers containing sulfenic acid groups, sulfinic acid groups, phosphoric acid groups, and the like can also be used.

  Specific examples of the monomer having a carboxyl group include, for example, α, β-ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, and α, such as itaconic acid, maleic acid, and fumaric acid. In addition to β-ethylenically unsaturated polyvalent carboxylic acid, α, β-ethylenically unsaturated polyvalent carboxylic acid partial esters such as methyl itaconate, butyl maleate and propyl fumarate can be exemplified. Moreover, what has group which can be induced | guided | derived to a carboxyl group by hydrolysis etc., such as maleic anhydride and itaconic anhydride, can be used similarly.

  Specific examples of the monomer having a sulfonic acid group include allyl sulfonic acid, methallyl sulfonic acid, vinyl sulfonic acid, styrene sulfonic acid, α, β-unsaturated sulfonic acid such as acrylamide-2-methylpropane sulfonic acid, And salts thereof.

  Among these monomers having an organic acid group, monomers having a carboxyl group are more preferable, and acrylic acid and methacrylic acid are particularly preferable. These are industrially inexpensive and can be easily obtained, have good copolymerizability with other monomer components, and are preferable in terms of productivity. These monomers (a2m) having an organic acid group may be used alone or in combination of two or more.

  In the monomer (a2m) having these organic acid groups, the monomer unit (a2) derived therefrom is 0.1% by mass or more and 20% by mass or less in the (meth) acrylic acid ester polymer (AP1). Preferably, it is used for the polymerization in such an amount that it is 0.5 mass% or more and 15 mass% or less. In use within the above range, the viscosity of the polymerization system during polymerization can be maintained within an appropriate range.

  The monomer unit (a2) having an organic acid group is introduced into the (meth) acrylic acid ester polymer by polymerization of the monomer (a2m) having an organic acid group as described above. Although simple and preferable, an organic acid group may be introduced by a known polymer reaction after the (meth) acrylic acid ester polymer is formed.

  The (meth) acrylic acid ester polymer (AP1) may contain a monomer unit (a3) derived from a monomer (a3m) containing a functional group other than an organic acid group.

  Examples of the functional group other than the organic acid group include a hydroxyl group, an amino group, an amide group, an epoxy group, and a mercapto group.

  Examples of the monomer having a hydroxyl group include (meth) acrylic acid hydroxyalkyl esters such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate.

  Examples of the monomer containing an amino group include N, N-dimethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, and aminostyrene.

  Examples of monomers having an amide group include α, β-ethylenically unsaturated carboxylic acid amide monomers such as acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, and N, N-dimethylacrylamide. Can be mentioned.

  Examples of the monomer having an epoxy group include glycidyl (meth) acrylate and allyl glycidyl ether.

  The monomer (a3m) containing a functional group other than the organic acid group may be used alone or in combination of two or more.

  The monomer (a3m) having a functional group other than these organic acid groups is such that the monomer unit (a3) derived therefrom is 10% by mass or less in the (meth) acrylic acid ester polymer (AP1). It is preferred to be used in the polymerization in an appropriate amount. By using 10 mass% or less of monomer (a3m), the viscosity at the time of superposition | polymerization can be kept appropriate.

  The (meth) acrylic acid ester polymer (AP1) has a (meth) acrylic acid ester monomer unit (a1) that forms a homopolymer having the above-described glass transition temperature of −20 ° C. or lower, and an organic acid group. In addition to the monomer unit (a2) and the monomer unit (a3) containing a functional group other than the organic acid group, it is derived from a monomer (a4m) copolymerizable with these monomers. The monomer unit (a4) may be contained. A monomer (a4m) may be used individually by 1 type, and may use 2 or more types together.

  The amount of the monomer unit (a4) derived from the monomer (a4m) is preferably 10% by mass or less, more preferably 5% by mass or less of the acrylate polymer (AP1).

  Although a monomer (a4m) is not specifically limited, As a specific example, (meth) acrylic acid ester monomers (a1m) other than (meth) acrylate monomer (a1m) that form a homopolymer having a glass transition temperature of −20 ° C. or lower are used. ) Acrylic acid ester monomer, α, β-ethylenically unsaturated polyvalent carboxylic acid complete ester, alkenyl aromatic monomer, conjugated diene monomer, non-conjugated diene monomer, vinyl cyanide monomer Carboxylic acid unsaturated alcohol ester, olefinic monomer and the like.

  Specific examples of the (meth) acrylate monomer other than the (meth) acrylate monomer (a1m) that forms a homopolymer having a glass transition temperature of −20 ° C. or lower include methyl acrylate (single The glass transition temperature of the polymer is 10 ° C., methyl methacrylate (105 ° C.), ethyl methacrylate (63 ° C.), propyl methacrylate (25 ° C.), butyl methacrylate (20 ° C.), and the like. be able to.

  Specific examples of the α, β-ethylenically unsaturated polyvalent carboxylic acid complete ester include dimethyl fumarate, diethyl fumarate, dimethyl maleate, diethyl maleate, dimethyl itaconate and the like.

  Specific examples of the alkenyl aromatic monomer include styrene, α-methylstyrene, methyl α-methylstyrene, vinyl toluene, and divinylbenzene.

Specific examples of the conjugated diene monomer, 1,3-butadiene, 2-methyl-1,3 - butadiene (isoprene synonymous), 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene , 2-chloro-1,3-butadiene, cyclopentadiene, and the like.

  Specific examples of the non-conjugated diene monomer include 1,4-hexadiene, dicyclopentadiene, ethylidene norbornene and the like.

  Specific examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethylacrylonitrile and the like.

  Specific examples of the carboxylic acid unsaturated alcohol ester monomer include vinyl acetate.

  Specific examples of the olefin monomer include ethylene, propylene, butene, pentene and the like.

  The weight average molecular weight (Mw) of the (meth) acrylic acid ester polymer (AP1) is preferably in the range of 100,000 to 400,000 as measured by gel permeation chromatography (GPC method). It is more preferable that it is in the range of 300 to 300,000.

  The (meth) acrylic acid ester polymer (AP1) is a (meth) acrylic acid ester monomer (a1m) that forms a homopolymer having a glass transition temperature of −20 ° C. or lower, a monomer having an organic acid group (A2m), a monomer containing a functional group other than an organic acid group (a3m) used as required, and a monomer copolymerizable with these monomers used as needed ( a4m) can be obtained particularly preferably by copolymerization.

  The polymerization method is not particularly limited, and may be any of solution polymerization, emulsion polymerization, suspension polymerization, bulk polymerization and the like, and may be other methods. Solution polymerization is preferred, and among them, solution polymerization using a carboxylic acid ester such as ethyl acetate or ethyl lactate or an aromatic solvent such as benzene, toluene or xylene as the polymerization solvent is more preferred.

  In the polymerization, the monomer may be added in portions to the polymerization reaction vessel, but it is preferable to add the whole amount at once.

  The method for initiating the polymerization is not particularly limited, but it is preferable to use a thermal polymerization initiator as the polymerization initiator. The thermal polymerization initiator is not particularly limited, and may be either a peroxide or an azo compound.

  Peroxide polymerization initiators include hydroperoxides such as t-butyl hydroperoxide, peroxides such as benzoyl peroxide and cyclohexanone peroxide, and persulfates such as potassium persulfate, sodium persulfate and ammonium persulfate. Can be mentioned. These peroxides can also be used as a redox catalyst in appropriate combination with a reducing agent.

  As the azo compound polymerization initiator, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile) And so on.

  Although the usage-amount of a polymerization initiator is not specifically limited, It is preferable that it is the range of 0.01 mass part or more and 50 mass parts or less with respect to 100 mass parts of monomers.

  Other polymerization conditions (polymerization temperature, pressure, stirring conditions, etc.) of these monomers are not particularly limited.

  After completion of the polymerization reaction, the obtained polymer is separated from the polymerization medium as necessary. The separation method is not particularly limited. In the case of solution polymerization, the (meth) acrylic acid ester polymer (AP1) can be obtained by placing the polymerization solution under reduced pressure and distilling off the polymerization solvent.

  The weight average molecular weight of the (meth) acrylic acid ester polymer (AP1) can be controlled by appropriately adjusting the amount of the polymerization initiator used in the polymerization and the amount of the chain transfer agent.

((Meth) acrylic acid ester monomer (α1))
As described above, as the polymer (S1), (meth) acrylic acid ester polymer (A1) is preferable, and (meth) acrylic acid ester polymer (A1) is (meth) acrylic acid ester. Those obtained by polymerizing the (meth) acrylic acid ester monomer (α1) in the presence of the polymer (AP1) are particularly preferred.

  The (meth) acrylic acid ester monomer (α1) is not particularly limited as long as it contains a (meth) acrylic acid ester monomer, but a homopolymer having a glass transition temperature of −20 ° C. or lower. It is preferable to contain the (meth) acrylic acid ester monomer (a5m) to form.

  As an example of the (meth) acrylic acid ester monomer (a5m) that forms a homopolymer having a glass transition temperature of −20 ° C. or lower, it is used for the synthesis of a (meth) acrylic acid ester polymer (AP1) (meta ) The same (meth) acrylate monomer as the acrylate monomer (a1m) can be mentioned. A (meth) acrylic acid ester monomer (a5m) may be used individually by 1 type, and may use 2 or more types together.

  The (meth) acrylic acid ester monomer (α1) may be used as a mixture of the (meth) acrylic acid ester monomer (a5m) and a monomer copolymerizable therewith.

  Particularly preferred (meth) acrylate monomer (α1) has a (meth) acrylate monomer (a5m) that forms a homopolymer having a glass transition temperature of −20 ° C. or lower, and has an organic acid group. It consists of a monomer (a6m) and a monomer (a7m) copolymerizable therewith.

  The ratio of the (meth) acrylic acid ester monomer (a5m) in the (meth) acrylic acid ester monomer (α1) is preferably 69.9% by mass or more and 99.8% by mass or less, more preferably 74. It is 5 mass% or more and 98.5 mass% or less. When the ratio of the (meth) acrylic acid ester monomer (a5m) is in the above range, the A-layer pressure-sensitive adhesiveness and flexibility are excellent.

  Examples of the monomer (a6m) having an organic acid group include a monomer having the same organic acid group as that exemplified as the monomer (a2m) used for the synthesis of the (meth) acrylic acid ester polymer (AP1). A polymer can be mentioned. As the monomer having an organic acid group (a6m), one type may be used alone, or two or more types may be used in combination.

  The ratio of the monomer (a6m) having an organic acid group in the (meth) acrylic acid ester monomer (α1) is preferably 0.1% by mass to 30% by mass, more preferably 1% by mass to 25%. It is below mass%. When the ratio of the monomer having an organic acid group (a6m) is in the above range, the hardness of the heat conductive pressure sensitive adhesive sheet is appropriate, and the pressure sensitive adhesive property at high temperature (100 ° C.) is good. It becomes.

  The (meth) acrylic acid ester monomer (α1) is a monomer capable of copolymerizing with the (meth) acrylic acid ester monomer (a5m) and the monomer having an organic acid group (a6m). The body (a7m) is preferably used in the range of 0.1% by mass to 20% by mass, more preferably 0.5% by mass to 15% by mass.

  Examples of the monomer (a7m) include a monomer (a3m), a monomer (a4m) used in the synthesis of the (meth) acrylic acid ester polymer (AP1), or a polyfunctional monomer shown below. The monomer similar to what is illustrated as a body can be mentioned.

  As the copolymerizable monomer (a7m), as described above, a polyfunctional monomer having two or more polymerizable unsaturated bonds can also be used. By copolymerizing the polyfunctional monomer, intramolecular and / or intermolecular crosslinking can be introduced into the copolymer to increase the cohesive force as a pressure-sensitive adhesive.

  Polyfunctional monomers include 1,6-hexanediol di (meth) acrylate, 1,2-ethylene glycol di (meth) acrylate, 1,12-dodecanediol di (meth) acrylate, polyethylene glycol di (meth) ) Acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ditrimethylolpropane tri ( Multifunctional (meth) acrylates such as (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 2,4-bis (trichloromethyl) Other substituted triazines, such as 6-p-methoxystyrene-5-triazine, etc. monoethylenically unsaturated aromatic ketones such as 4-acryloxy benzophenone can be used. Among these, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate are preferable.

  The (meth) acrylic acid ester monomer (α1) preferably contains the above polyfunctional monomer. The polyfunctional monomer is used as all or part of the monomer (a7m). As the polyfunctional monomer, the (meth) acrylic acid ester monomer (α1) is 100% by mass. Preferably, it is contained in an amount of 0.1 to 5% by mass, more preferably 0.5 to 3% by mass.

  The amount of the (meth) acrylic acid ester monomer (α1) contained in the heat conductive pressure-sensitive adhesive composition (E1) is the lower limit with respect to 100 parts by mass of the (meth) acrylic acid ester polymer (AP1). Is preferably 20 parts by mass, more preferably 40 parts by mass, and even more preferably 60 parts by mass. The upper limit is preferably 170 parts by mass, more preferably 150 parts by mass, and even more preferably 130 parts by mass. When the amount of the (meth) acrylic acid ester monomer (α1) contained in the heat conductive pressure-sensitive adhesive composition (E1) is less than the lower limit (20 parts by mass) or exceeds the upper limit (170 parts by mass) of the above range. When layer A is used, the pressure-sensitive adhesive retention may be inferior.

  When forming the A layer, the (meth) acrylic acid ester monomer (α1) in the heat conductive pressure-sensitive adhesive composition (E1) is polymerized. In order to accelerate the polymerization, the heat conductive pressure-sensitive adhesive composition (E1) is added to the (meth) acrylic acid ester polymer (AP1) and the (meth) acrylic acid ester monomer (α1), It preferably contains a polymerization initiator.

  Examples of the polymerization initiator include a photopolymerization initiator, an azo thermal polymerization initiator, an organic peroxide thermal polymerization initiator, and the like. From the viewpoint of the adhesive strength of the resulting A layer, the organic peroxide thermal polymerization is performed. Initiators are preferably used.

  Various known photopolymerization initiators can be used as the photopolymerization initiator. Among these, a phosphine oxide compound is preferable. Examples of the phosphine oxide compound that is a preferred photopolymerization initiator include bis (2,4,6-trimethylbenzyl) phenylphosphine oxide and 2,4,6-trimethylbenzyldiphenylphosphine oxide.

  As the azo thermal polymerization initiator, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile) ) And the like.

  As the organic peroxide thermal polymerization initiator, hydroperoxide such as t-butyl hydroperoxide, benzoyl peroxide, cyclohexanone peroxide, 1,6-bis (t-butylperoxycarbonyloxy) hexane, 1,1-bis ( Examples thereof include peroxides such as (t-butylperoxy) -3,3,5-trimethylcyclohexanone, but it is preferable not to release volatile substances that cause odor during thermal decomposition. Among organic peroxide thermal polymerization initiators, those having a one-minute half-life temperature of 100 ° C. or more and 170 ° C. or less are preferable.

  The amount of the polymerization initiator such as the organic peroxide thermal polymerization initiator used is preferably 0.1 parts by mass, more preferably 100 parts by mass with respect to 100 parts by mass of the (meth) acrylate monomer (α1). 0.3 parts by mass, more preferably 0.5 parts by mass, and the upper limit is preferably 10 parts by mass, more preferably 5 parts by mass, and even more preferably 3 parts by mass.

  The polymerization conversion rate of the (meth) acrylic acid ester monomer (α1) is preferably 95% by mass or more. If the polymerization conversion rate is too low, the monomer odor remains in the resulting A layer, which is not preferable.

<Expanded graphite powder (B)>
The layer A preferably contains expanded graphite powder (B). As an example of the expanded graphite powder (B) that can be used in the present invention, acid-treated graphite is heat-treated at 500 ° C. to 1200 ° C. to expand to 100 ml / g to 300 ml / g, and then pulverized. What was obtained through the process containing this can be mentioned. More preferably, the graphite is treated with a strong acid, sintered in an alkali, and then again treated with a strong acid at 500 ° C. to 1200 ° C. to remove the acid and to 100 ml / g to 300 ml / g. What was obtained through the process including expanding and then crushing can be mentioned. The temperature of the heat treatment is particularly preferably 800 ° C to 1000 ° C.

  The average particle size of the expanded graphite powder (B) used in the present invention is preferably 30 μm to 500 μm, more preferably 50 μm to 400 μm, and still more preferably 80 μm to 300 μm. When the average particle diameter of the expanded graphite powder (B) is less than the lower limit (30 μm) of the above range, the thermal conductivity of the A layer tends to be low. On the other hand, when the average particle diameter of the expanded graphite powder (B) exceeds the upper limit (500 μm) of the above range, the expanded graphite powder (B) exists in a large domain on the surface of the A layer, There is a possibility that voids are likely to be formed at the interface, and the thermal conductivity and adhesiveness of the A layer may be lowered, and the moldability may be deteriorated.

  The average particle size of the expanded graphite powder (B) is measured using a laser-type particle size measuring machine (manufactured by Seishin Enterprise Co., Ltd.) and a micro-sorting control method (measuring particles are allowed to pass only within the measurement region to ensure measurement reliability (Measure to improve). In this measurement method, 0.01 g to 0.02 g of the expanded graphite powder (B) to be measured is flowed into the cell, so that the expanded graphite powder (B) flowing into the measurement region has a semiconductor with a wavelength of 670 nm. By irradiating the laser beam and measuring the scattering and diffraction of the laser beam at that time, the average particle size and particle size distribution are calculated from the Franhofer diffraction principle, and the results are displayed.

The amount of the expanded graphite powder (B) contained in the A layer is preferably 30 parts by mass or more and 800 parts by mass or less, and 100 parts by mass or more and 800 parts by mass or less, based on 100 parts by mass of the polymer (S1). More preferably, it is more than 300 parts by mass and 750 parts by mass or less.
If content of expanded graphite powder (B) is less than the said minimum (30 mass parts), it exists in the tendency for the thermal conductivity of A layer to be inferior. On the other hand, if the content of the expanded graphite powder (B) exceeds the upper limit (800 parts by mass), there is a possibility that problems such as difficulty in forming a heat conductive pressure-sensitive adhesive laminate sheet (F) may occur. .

<Thermal conductive inorganic compound other than expanded graphite powder as an optional component in the thermally conductive pressure sensitive adhesive composition (E1)>
<PITCH carbon fiber (C)>
The PITCH-based carbon fiber (C) that can be used as an optional component in the heat conductive pressure-sensitive adhesive composition (E1) is carbon fiber using pitch (by-products such as petroleum, coal, coal tar) as a raw material. And has a feature of high thermal conductivity. When the PITCH-based carbon fiber (C) is contained in the thermally conductive pressure-sensitive adhesive composition (E1), the content is preferably 400 parts by mass or less, more preferably 100 parts by mass or less, with the polymer (S1) being 100 parts by mass. Is preferably 300 parts by mass or less, more preferably 270 parts by mass or less. When the content of the PITCH-based carbon fiber (C) exceeds the upper limit (400 parts by mass) of the above range, when the heat conductive pressure-sensitive adhesive composition (E1) is used as the A layer, the surface state of the A layer is It tends to get worse.

<Flame-retardant thermally conductive inorganic compound (D1)>
The flame retardant thermally conductive inorganic compound (D1) that can be used in the thermally conductive pressure sensitive adhesive composition (E1) as an optional component is not particularly limited, and specific examples thereof include aluminum hydroxide, water Examples thereof include magnesium oxide, calcium hydroxide, dihydrate gypsum, zinc borate, kaolin clay, calcium aluminate, calcium carbonate, aluminum carbonate, and dawsonite. A flame-retardant heat conductive inorganic compound (D1) may be used individually by 1 type, and may use 2 or more types together.

  The shape of the flame retardant thermally conductive inorganic compound (D1) is not particularly limited, and may be any of spherical, acicular, fibrous, scale-like, dendritic, flat, and indefinite shapes.

  Among the flame retardant thermally conductive inorganic compounds (D1), aluminum hydroxide is particularly preferable. By using aluminum hydroxide, excellent flame retardancy can be imparted to the A layer.

  As the aluminum hydroxide, one having a particle diameter of usually 0.2 μm to 150 μm, preferably 0.7 μm to 100 μm is used. Moreover, it is preferable to have an average particle diameter of 1 μm to 80 μm. When the average particle size is less than 1 μm, the viscosity of the heat conductive pressure-sensitive adhesive composition (E1) is increased, the hardness is increased at the same time, and the shape following property of the A layer may be decreased. The conductivity tends to be low. On the other hand, when the average particle size exceeds 80 μm, the surface of the A layer becomes rough, and there is a possibility that the adhesive force is reduced at a high temperature or thermally deformed at a high temperature.

  The amount of the flame retardant thermally conductive inorganic compound (D1) contained in the thermally conductive pressure-sensitive adhesive composition (E1) is preferably 300 parts by mass or less, more preferably 100 parts by mass or less, more preferably 100 parts by mass of the polymer (S1). The amount is desirably 250 parts by mass or less. When the content of the flame retardant thermally conductive inorganic compound (D1) exceeds the upper limit (300 parts by mass) of the above range, the hardness of the A layer increases and the shape followability tends to decrease.

<Other ingredients>
The heat conductive pressure-sensitive adhesive composition (E1) may further contain various known additives such as a foaming agent, an external cross-linking agent, a pigment, other fillers, an anti-aging agent, and a thickener, if necessary. It can contain in the range which does not impair the effect of this invention.

(Foaming agent)
A foaming agent can also be added to the heat conductive pressure-sensitive adhesive composition (E1) in order to foam the A layer obtained therefrom. As the foaming agent, a thermally decomposable organic foaming agent is preferable. Furthermore, as a thermally decomposable organic foaming agent, what has a decomposition start temperature of 80 degreeC or more and 200 degrees C or less is preferable.

  Specific examples of such thermally decomposable organic foaming agents include 4,4'-oxybis (benzenesulfonyl hydrazide). Similarly, a foaming system in which a certain amount of a foaming aid described later is mixed with an organic foaming agent having a thermal decomposition starting temperature higher than 200 ° C., such as azodicarboxamide, and the thermal decomposition starting temperature is set to 100 ° C. or higher and 200 ° C. or lower. It can be a thermally decomposable organic foaming agent.

  Examples of the foaming aid include zinc stearate, a mixture of stearic acid and zinc white (zinc oxide), zinc laurate, a mixture of lauric acid and zinc white, zinc palmitate, a mixture of palmitic acid and zinc white, stearin Examples include sodium acid, sodium laurate, sodium palmitate, potassium stearate, potassium laurate, and potassium palmitate.

(External crosslinking agent)
In addition, an external cross-linking agent is added to the heat conductive pressure-sensitive adhesive composition (E1) in order to increase cohesion as a pressure-sensitive adhesive and improve heat resistance, and (meth) acrylic ester. A crosslinked structure can be introduced into a polymer obtained by polymerizing the (meth) acrylic acid ester monomer (α1) in the presence of the polymer (AP1).

  Examples of external crosslinking agents include polyfunctional isocyanate crosslinking agents such as tolylene diisocyanate, trimethylolpropane diisocyanate, diphenylmethane triisocyanate; epoxy crosslinking such as diglycidyl ether, polyethylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether Melamine resin crosslinking agent; amino resin crosslinking agent; metal salt crosslinking agent; metal chelate crosslinking agent; peroxide crosslinking agent;

  The external crosslinking agent is obtained by polymerizing the (meth) acrylic acid ester monomer (α1) in the presence of the (meth) acrylic acid ester polymer (AP1), and then added to this. By performing heat treatment or radiation irradiation treatment, a cross-link is formed within and / or between the molecules of the copolymer.

(Other)
The pigment can be used regardless of organic type or inorganic type such as carbon black and titanium dioxide. Examples of other fillers include inorganic compounds such as clay. You may add nanoparticles, such as fullerene and a carbon nanotube. Antioxidants such as polyphenols, hydroquinones, and hindered amines can be used as the anti-aging agent because they are likely to inhibit radical polymerization and are not usually used. As the thickener, inorganic polymer fine particles such as acrylic polymer particles and fine silica, and reactive inorganic compounds such as magnesium oxide can be used.

1.2. B1 layer B1 layer consists of a heat conductive pressure sensitive adhesive composition (E2) containing at least 1 type of polymer (S2) chosen from the group which consists of rubber | gum, an elastomer, and resin.

  In addition, in this invention, although B1 layer is a layer which consists of a heat conductive pressure sensitive adhesive composition (E2), a heat conductive substance (E2) is positively included in a heat conductive pressure sensitive adhesive composition (E2). For example, carbon black, graphite, aluminum hydroxide, boron nitride, etc.) need not be contained. Usually, rubbers, elastomers, and resins are inherently thermally conductive. Therefore, even if it does not actively contain a heat conductive substance, it can be handled as a heat conductive pressure sensitive adhesive composition (E2), and as shown in the examples, the B1 layer and the B2 layer are formed on both sides of the A layer. The heat conductive pressure-sensitive adhesive laminated sheet (F) of the present invention has excellent heat conductivity even when the B1 layer and the B2 layer do not actively contain a heat conductive material.

<Polymer (S2)>
Since the polymer (S2) can be the same as (S1) described above, detailed description thereof is omitted.

((Meth) acrylic acid ester polymer (A2))
The polymer (S2) is preferably a (meth) acrylic acid ester polymer (A2), and the (meth) acrylic acid ester polymer (A2) is present in the presence of a (meth) acrylic acid ester polymer (AP2). Those obtained by polymerizing the (meth) acrylic acid ester monomer (α2) below are particularly preferred. When the heat conductive pressure-sensitive adhesive composition (E2) is formed into a B1 layer, the heat conductive pressure-sensitive adhesive composition (E2) is formed into a sheet shape or after being formed into a sheet shape, The (meth) acrylic acid ester monomer (α2) in the heat conductive pressure-sensitive adhesive composition (E2) is polymerized and converted into a (meth) acrylic acid ester polymer. The (meth) acrylic acid ester polymer (A2) is obtained by mixing and / or partially bonding with the component (AP2). The (meth) acrylic acid ester polymer (A2) corresponds to all the (meth) acrylic acid ester polymer components in the B1 layer, and comprehensively includes all the (meth) acrylic acid ester polymer components in the B1 layer. It is a concept to represent.

((Meth) acrylic acid ester polymer (AP2))
Since the (meth) acrylic acid ester polymer (AP2) is the same as the (meth) acrylic acid ester polymer (AP1), detailed description thereof is omitted.

((Meth) acrylic acid ester monomer (α2))
Since the (meth) acrylic acid ester monomer (α2) is the same as the (meth) acrylic acid ester monomer (α1), detailed description thereof is omitted.

<Thermal conductive inorganic compound as an optional component in the thermally conductive pressure sensitive adhesive composition (E2)>
<Flame-retardant thermally conductive inorganic compound (D2)>
As an optional component, the flame retardant heat conductive inorganic compound (D2) that can be used in the heat conductive pressure sensitive adhesive composition (E2) is not particularly limited, and specific examples thereof include aluminum hydroxide, Examples thereof include magnesium hydroxide, calcium hydroxide, dihydrate gypsum, zinc borate, kaolin clay, calcium aluminate, calcium carbonate, aluminum carbonate, and dawsonite. A flame-retardant heat conductive inorganic compound (D2) may be used individually by 1 type, and may use 2 or more types together.

  The shape of the flame retardant thermally conductive inorganic compound (D2) is not particularly limited, and may be any of spherical, acicular, fibrous, scale-like, dendritic, flat, and indeterminate shapes.

  Among the flame retardant thermally conductive inorganic compounds (D2), aluminum hydroxide is particularly preferable. By using aluminum hydroxide, excellent flame retardancy can be imparted to the B1 layer.

  As the aluminum hydroxide, one having a particle diameter of usually 0.2 μm to 150 μm, preferably 0.7 μm to 100 μm is used. Moreover, it is preferable to have an average particle diameter of 1 μm to 80 μm. When the average particle size is less than 1 μm, the viscosity of the heat conductive pressure-sensitive adhesive composition (E2) is increased, and at the same time, the hardness is increased, and the shape following property of the B1 layer may be decreased. The conductivity tends to be low. On the other hand, when the average particle size exceeds 80 μm, the surface of the B1 layer becomes rough, and there is a possibility that the adhesive strength is lowered at high temperature or the film is thermally deformed at high temperature.

  The amount of the flame retardant thermally conductive inorganic compound (D2) contained in the thermally conductive pressure-sensitive adhesive composition (E2) is preferably 300 parts by mass or less, more preferably 100 parts by mass or less, more preferably 100 parts by mass of the polymer (S2). The amount is desirably 250 parts by mass or less. When the content of the flame retardant thermally conductive inorganic compound (D2) exceeds the upper limit (300 parts by mass) of the above range, the hardness of the B1 layer increases and the shape followability tends to decrease.

<Other ingredients>
In the heat conductive pressure-sensitive adhesive composition (E2), as in the case of the heat conductive pressure-sensitive adhesive composition (E1), if necessary, a foaming agent, an external cross-linking agent, a pigment, other fillers, an anti-aging agent, Various known additives such as thickeners can be contained within a range not impairing the effects of the present invention. Since other components that can be added are the same as those of the heat conductive pressure-sensitive adhesive composition (E1), detailed description thereof is omitted.

1.3. B2 layer B2 layer consists of a heat conductive pressure sensitive adhesive composition (E3) containing at least 1 type of polymer (S3) chosen from the group which consists of rubber | gum, an elastomer, and resin.

  In addition, in this invention, although B2 layer is a layer which consists of a heat conductive pressure sensitive adhesive composition (E3), in a heat conductive pressure sensitive adhesive composition (E3), a heat conductive substance ( For example, carbon black, graphite, aluminum hydroxide, boron nitride, etc.) need not be contained. Usually, rubbers, elastomers, and resins are inherently thermally conductive. Therefore, even if it does not actively contain a heat conductive substance, it can be handled as a heat conductive pressure-sensitive adhesive composition (E3). As shown in the examples, the B1 layer and the B2 layer are formed on both sides of the A layer. The heat conductive pressure-sensitive adhesive laminated sheet (F) of the present invention has excellent heat conductivity even when the B1 layer and the B2 layer do not actively contain a heat conductive material.

<Polymer (S3)>
Since the polymer (S3) can be the same as (S1) described above, detailed description thereof is omitted.

((Meth) acrylic acid ester polymer (A3))
The polymer (S3) is preferably a (meth) acrylic acid ester polymer (A3), and the (meth) acrylic acid ester polymer (A3) is present in the presence of a (meth) acrylic acid ester polymer (AP3). Those obtained by polymerizing the (meth) acrylic acid ester monomer (α3) below are particularly preferred. When the heat conductive pressure sensitive adhesive composition (E3) is formed into a B2 layer, the heat conductive pressure sensitive adhesive composition (E3) is formed into a sheet shape or after being formed into a sheet shape, The (meth) acrylic acid ester monomer (α3) in the heat conductive pressure-sensitive adhesive composition (E3) is polymerized and converted to a (meth) acrylic acid ester polymer, and a (meth) acrylic acid ester polymer is obtained. A (meth) acrylic acid ester polymer (A3) is obtained by mixing and / or partially bonding with the component (AP3). The (meth) acrylic acid ester polymer (A3) corresponds to all the (meth) acrylic acid ester polymer components in the B2 layer, and comprehensively includes all the (meth) acrylic acid ester polymer components in the B2 layer. It is a concept to represent.

((Meth) acrylic acid ester polymer (AP3))
Since the (meth) acrylic acid ester polymer (AP3) is the same as the (meth) acrylic acid ester polymer (AP1), detailed description thereof is omitted.

((Meth) acrylic acid ester monomer (α3))
Since the (meth) acrylic acid ester monomer (α3) is the same as the (meth) acrylic acid ester monomer (α1), detailed description thereof is omitted.

<Thermal conductive inorganic compound as an optional component in the thermally conductive pressure sensitive adhesive composition (E3)>
<Flame-retardant thermally conductive inorganic compound (D3)>
The flame retardant thermally conductive inorganic compound (D3) that can be used in the thermally conductive pressure-sensitive adhesive composition (E3) as an optional component is the above-described thermally conductive inorganic compound (D2) as an optional component in E2. Detailed description will be omitted.

<Other ingredients>
In the heat conductive pressure-sensitive adhesive composition (E3), as in the case of the heat conductive pressure-sensitive adhesive composition (E1), if necessary, a foaming agent, an external cross-linking agent, a pigment, other fillers, an anti-aging agent, Various known additives such as thickeners can be contained within a range not impairing the effects of the present invention. Since other components that can be added are the same as those of the heat conductive pressure-sensitive adhesive composition (E1), detailed description thereof is omitted.

1.4. Lamination method A heat conductive pressure-sensitive-adhesive lamination sheet (F) is obtained by shape | molding A layer, B1 layer, and B2 layer, and laminating | stacking those layers. Moreover, after shape | molding any layer of A layer, B1 layer, and B2 layer, a heat conductive pressure sensitive adhesive composition (E1) and a heat conductive pressure sensitive adhesive composition (E2) on the shape | molded layer. ) Or the heat conductive pressure-sensitive adhesive composition (E3), and the other layers are sequentially formed and laminated in layers to obtain the heat conductive pressure-sensitive adhesive laminate sheet (F). Since the forming method of the A layer, the B1 layer, and the B2 layer is the same, the forming method of the A layer will be described below.

  A layer consists of a heat conductive pressure-sensitive-adhesive composition (E1) heated while shape | molding in a sheet form, or after shape | molding in a sheet form. Preferably, the heat conductive pressure sensitive adhesive composition (E1) contains a (meth) acrylic acid ester polymer (AP1) and a (meth) acrylic acid ester monomer (α1), and the heat conductive pressure sensitive adhesive While forming the composition (E1) into a sheet shape or after forming into a sheet shape, the (meth) acrylate monomer (α1) in the presence of the (meth) acrylate polymer (AP1) Is a solidified sheet-like molded body of the heat-conductive pressure-sensitive adhesive composition (E1) obtained by polymerizing.

  However, when the content of the liquid component typified by a monomer or the like in the heat conductive pressure-sensitive adhesive composition (E1) is 5% by mass or less, the heat conductive pressure-sensitive adhesive composition (E1) ) Can be regarded as substantially equivalent to the case of solidification. In fact, it can be considered that the heat conductive pressure-sensitive adhesive composition (E1) that does not contain a liquid component such as the (meth) acrylic acid ester monomer (α1) is equivalent to the case where it is solidified.

  In the heat conductive pressure sensitive adhesive composition (E1), when the content of the liquid component represented by the monomer or the like in the heat conductive pressure sensitive adhesive composition (E1) is 5% by mass or less. Can form the heat conductive pressure sensitive adhesive composition (E1) as it is without forming the liquid component (for example, polymerizing the monomer) as it is.

  The method for forming the heat conductive pressure-sensitive adhesive composition (E1) into a sheet is not particularly limited. Suitable methods include, for example, a casting method in which the heat conductive pressure-sensitive adhesive composition (E1) is applied onto a process paper such as a peeled polyester film, and a heat conductive pressure-sensitive adhesive composition (E1). Examples of the method include a method of sandwiching between two exfoliated process papers if necessary and passing between rolls, and a method of controlling the thickness through a die when extruding using an extruder.

  While forming into a sheet or after forming into a sheet, for example, the A layer can be suitably obtained by heating the heat conductive pressure-sensitive adhesive composition (E1) with hot air, an electric heater, infrared rays or the like. The heating temperature at this time is preferably such that the organic peroxide thermal polymerization initiator decomposes efficiently and the polymerization of the (meth) acrylic acid ester monomer (α1) proceeds. Although a temperature range changes with kinds of organic peroxide thermal-polymerization initiator to be used, 100 to 200 degreeC is preferable and 130 to 180 degreeC is more preferable.

  A layer forms a heat conductive pressure-sensitive-adhesive composition (E1) in a sheet form, and heats it to the temperature of 100 degreeC or more and 200 degrees C or less, and heat conductive pressure-sensitive-adhesive composition (E1) It is preferable that it is a sheet-like molded object formed by forming a sheet and polymerizing the (meth) acrylic acid ester monomer (α1).

1.5. Other Configurations The heat conductive pressure-sensitive adhesive laminate sheet (F) of the present invention may be composed of only three layers of the A layer, the B1 layer, and the B2 layer, and the A layer, the B1 layer, and the B2 layer. The composite body provided with the base material on one surface side or both surface sides of the laminate made of may be used. The type of the substrate is not particularly limited.

  When the heat-conductive pressure-sensitive adhesive laminate sheet (F) is composed of only three layers of the A layer, the B1 layer, and the B2 layer, as described above, the B1 layer and the B2 layer may be provided with adhesiveness. Therefore, it can be set as the laminated sheet which has adhesiveness on both surfaces.

  When a substrate is provided on one side or both sides of a laminate comprising the A layer, the B1 layer, and the B2 layer, specific examples of the substrate include heat such as aluminum, copper, stainless steel, and beryllium copper. Metal and alloy foils with excellent conductivity, sheet-like materials made of polymers with excellent thermal conductivity such as thermal conductive silicone itself, thermally conductive plastic films containing thermally conductive fillers, And various nonwoven fabrics, glass cloths, honeycomb structures, and the like.

  Plastic films include polyimide, polyethylene terephthalate, polyethylene naphthalate, polytetrafluoroethylene, polyether ketone, polyethersulfone, polymethylpentene, polyetherimide, polysulfone, polyphenylene sulfide, polyamideimide, polyesterimide, aromatic polyamide, etc. A film made of a heat-resistant polymer can be used.

1.6. Performance of heat conductive pressure-sensitive adhesive sheet (F) In conventional heat conductive pressure-sensitive adhesive sheets, if a large amount of expanded graphite powder (B) is contained, formability deteriorates (it does not become a sheet). The amount in which the graphite oxide powder (B) was contained was limited. On the other hand, in the present invention, the thermally conductive pressure-sensitive adhesive laminate sheet (F) having at least three layers is used to highly fill the expanded graphite powder (B) into the A layer sandwiched between the B1 layer and the B2 layer. Is possible. Therefore, the layer A can be provided with high thermal conductivity. Further, the B1 layer and the B2 layer can be provided with thermal conductivity, insulation, and flexibility. Therefore, the heat conductive pressure-sensitive adhesive laminate sheet (F) in which the flexible A layer is sandwiched between the B1 layer and the B2 layer having the same or higher flexibility as the A layer has high heat conductivity and insulation. Therefore, it is possible to obtain a laminated sheet having excellent properties and flexibility and excellent adhesion between layers.

  The thicknesses of the A layer, the B1 layer, and the B2 layer in the heat conductive pressure-sensitive adhesive laminated sheet (F) of the present invention are not particularly limited, but the thicknesses of the B1 layer and the B2 layer are 1 μm or more and 1500 μm or less. Is preferably 10 μm or more and 150 μm or less. If the B1 layer and the B2 layer are too thin, it is difficult to obtain an effect (insulation improvement) by sandwiching the A layer between the B1 layer and the B2 layer, and if the B1 layer and the B2 layer are too thick, the thermal conductivity tends to be inferior. . The thickness of the A layer is preferably 100 μm or more and 3000 μm or less, and more preferably 500 μm or more and 1500 μm or less. If the A layer is too thin, the thermal conductivity in the surface direction tends to be inferior, and if it is too thick, the thickness of the heat conductive pressure-sensitive adhesive laminate sheet (F) becomes thick, which may cause the following problems. . The thickness of the heat conductive pressure-sensitive adhesive laminated sheet (F) is usually 10 μm to 3000 μm. If the thickness is less than 10 μm, the heat diffusion performance may be deteriorated particularly in the surface direction, and air may be easily involved when sticking to the heating element and the heat dissipation element, and as a result, sufficient thermal conductivity may not be obtained. There is. On the other hand, if it is thicker than 3000 μm, the heat resistance in the thickness direction of the heat conductive pressure-sensitive adhesive laminate sheet (F) increases, and there is a possibility that heat dissipation may be impaired, and it becomes impossible to secure a use space in a thinned device or the like. there is a possibility.

  In the heat conductive pressure-sensitive adhesive laminate sheet (F) of the present invention, the B1 layer and the B2 layer may have the same configuration or may have different configurations, but preferably have the same configuration. . By using the layers having the same structure, both the B1 layer and the B2 layer can be produced without changing the raw materials and the production process, so that workability is improved.

2. Electronic component The heat conductive pressure-sensitive adhesive laminated sheet (F) of the present invention described above can be used as a part of an electronic component. In that case, it can also form directly on base materials, such as a heat radiator, and can also provide as a part of electronic component. Specific examples of the electronic component include components around a heat generating part in a device having an electroluminescence (EL) light emitting diode (LED) light source, components around a power device such as an automobile, a fuel cell, a solar cell, a battery, and a mobile phone. And devices and parts having a heat generating part such as a personal digital assistant (PDA), a notebook computer, a liquid crystal, a surface conduction electron-emitting device display (SED), a plasma display panel (PDP), or an integrated circuit (IC). .

  In addition, as an example of the usage method for the electronic device of the heat conductive pressure-sensitive-adhesive laminated sheet (F) of this invention, it can mention using an LED light source by the method as described in a specific example below. Attaching directly to the LED light source; sandwiching between the LED light source and heat dissipation material (heat sink, fan, Peltier element, heat pipe, graphite sheet, etc.); Heat dissipation material connected to the LED light source (heat sink, fan, Peltier element) , Heat pipe, graphite sheet, etc.); used as a casing surrounding the LED light source; affixed to the casing surrounding the LED light source; and filling a gap between the LED light source and the casing. Application examples of LED light sources include backlight devices for display devices having a transmissive liquid crystal panel (TVs, mobile phones, PCs, notebook PCs, PDAs, etc.); vehicle lamps; industrial lighting; commercial lighting; Lighting; and the like.

  Specific examples other than the LED light source include the following. That is, PDP panel; IC heating part; Cold cathode tube (CCFL); Organic EL light source; Inorganic EL light source; High luminance light emitting LED light source; High luminance light emitting organic EL light source; And so on.

  Furthermore, as a usage method of the heat conductive pressure-sensitive-adhesive laminated sheet (F) of the present invention, it can be mentioned that it is attached to the housing of the apparatus. For example, in an apparatus used for an automobile or the like, it is attached to the inside of a casing provided in the automobile; it is attached to the exterior of the casing provided in the automobile; a heat generating part (car navigation / A fuel cell / heat exchanger) and the casing; and affixing to a heat sink connected to a heat generating part (car navigation / fuel cell / heat exchanger) in the casing of the automobile; Can be mentioned.

  In addition to a motor vehicle, the heat conductive pressure-sensitive-adhesive sheet (F) of this invention can be used by the same method. For example, a personal computer; a house; a TV; a mobile phone; a vending machine; a refrigerator; a solar cell; a surface conduction electron-emitting device display (SED); an organic EL display; an inorganic EL display; Notebook PCs; PDAs; fuel cells; semiconductor devices; rice cookers; washing machines; washing dryers; optical semiconductor devices combining optical semiconductor elements and phosphors; various power devices;

  Furthermore, the heat conductive pressure-sensitive-adhesive laminated sheet (F) of the present invention is not limited to the above method of use, and can be used according to applications. For example, used for heat equalization of carpets and warm mats; used as LED light source / heat source sealant; used as solar cell sealant; used as solar cell backsheet Used between the backsheet of the solar cell and the roof; used inside the heat insulating layer inside the vending machine; used inside the housing of the organic EL lighting with a desiccant and a hygroscopic agent; organic EL lighting Use with desiccant and hygroscopic agent on the heat conductive layer inside the housing of the LED; Use with desiccant and hygroscopic agent on the heat conductive layer and heat dissipation layer inside the housing of the organic EL lighting Used for heat conduction layer inside the housing of organic EL lighting, epoxy heat dissipation layer, and on top of it with desiccant and hygroscopic agent; cooling equipment, clothing, towels, sheets, etc. for cooling humans and animals On the opposite side of the body to the member Used for a pressure member of a fixing device mounted on an image forming apparatus such as an electrophotographic copying machine or an electrophotographic printer; Pressurizing a fixing device mounted on an image forming apparatus such as an electrophotographic copying machine or an electrophotographic printer Used as a member itself; used as a heat flow control heat transfer part for placing a treatment object of a membrane control device; used as a heat flow control heat transfer part for placing a treatment object of a film control device; outer layer of a radioactive substance storage container It can be used between the interior and interior; used in a box body with a solar panel that absorbs sunlight; used between the reflective sheet of the CCFL backlight and the aluminum chassis.

  Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to the examples. The “parts” and “%” used here are based on mass unless otherwise specified.

<Thickness>
The thickness of each layer of the heat conductive pressure sensitive adhesive sheet or the sheet constituting the heat conductive pressure sensitive adhesive sheet was measured. For a layer provided with a polyethylene terephthalate film with a release agent (hereinafter referred to as “release PET”), the thickness of the release PET is corrected to zero, and the thickness is measured with the release PET attached. The sample was placed on a vessel and the thickness was measured. The results are shown in Tables 1 and 2.

<Surface resistance>
For a test piece obtained by cutting a heat conductive pressure-sensitive adhesive laminate sheet or a heat conductive pressure-sensitive adhesive sheet into a width of 50 mm and a length of 50 mm, current is passed through both ends in the width direction of the surface, and the electric resistance value is confirmed. did. About the same test piece, the resistance value was measured 3 times by the said method, and the average value was calculated | required. The results are shown in Tables 3 and 4.

<Peeling at the interface>
The appearance of the interface of each layer constituting the heat conductive pressure-sensitive adhesive laminated sheet was visually confirmed in an atmosphere of 100 degrees Celsius. The results are shown in Tables 3 and 4 where “Yes” indicates that the interface has been confirmed to be naturally peeled, and “No” indicates that the peeling has not been confirmed.

<Adhesion>
One surface of a test piece obtained by cutting a heat conductive pressure-sensitive adhesive laminated sheet into a size of 25 mm wide × 125 mm long is attached to an aluminum plate while lightly pressing from one side with a finger, and a roller of 2 kg is applied at 10 mm / second. Press and reciprocate once at a speed and let stand for 30 minutes or more. Next, the glass plate was placed in parallel with the other surface of the test piece, and the adhesion rate between the glass plate and the test piece 30 seconds after the glass plate was placed was measured. The measurement was carried out using a color copier, scanned for adhesion to a glass plate, read with a PC (personal computer), and digitized using image analysis software (AnalySIS). The results are shown in Tables 3 and 4.

<Thermal characteristics>
About the test piece which cut | judged the heat conductive pressure-sensitive-adhesive lamination sheet to the magnitude | size of width 50mm x length 80mm, the flat-plate-shaped ceramic heater from which a contact area becomes 25 mm x 25 mm was mounted on the surface. At this time, the ceramic heater was positioned at the center of the test piece. Thereafter, a voltage of 16.5 V was applied to the ceramic heater in an atmosphere of 23 ° C., and after 60 minutes, the ceramic heater and the test piece were photographed from the upper surface side by thermovision. The highest temperature part of the ceramic heater was confirmed, and the value obtained by subtracting the temperature of the ceramic heater when the test piece was not in contact with the ceramic heater was taken as the thermal characteristic evaluation result. The smaller the value of the thermal characteristic, the higher the heat dissipation performance. The results are shown in Tables 3 and 4.

<Production of sheet>
Sheets (X1), (X2), (X3), (X4), (X5), (Y1), (Y1 ′), (Y1 ″), (Y2), and (Y3) used in Examples and Comparative Examples ) Was prepared by the following procedure.

(Sheet (X1))
A reactor was charged with 100 parts of a monomer mixture composed of 94% 2-ethylhexyl acrylate and 6% acrylic acid, 0.03 parts 2,2′-azobisisobutyronitrile and 700 parts ethyl acetate. Then, after substitution with nitrogen, a polymerization reaction was carried out at 80 ° C. for 6 hours. The polymerization conversion rate was 97%. The obtained polymer was dried under reduced pressure to evaporate ethyl acetate to obtain a viscous solid (meth) acrylate polymer. The weight average molecular weight (Mw) of the (meth) acrylic acid ester polymer was 270,000, and the weight average molecular weight (Mw) / number average molecular weight (Mn) was 3.1. The weight average molecular weight (Mw) and the number average molecular weight (Mn) were determined in terms of standard polystyrene by gel permeation chromatography using tetrahydrofuran as an eluent.

  Next, using an electronic balance, 1.1 parts of a polyfunctional monomer obtained by mixing pentaerythritol triacrylate, pentaerythritol tetraacrylate and pentaerythritol diacrylate in a ratio of 60: 35: 5, 2-ethylhexyl acrylate (Hereinafter abbreviated as “2EHA”) 17.4 parts, methacrylic acid (hereinafter abbreviated as “MAA”) 1.7 parts, 1,6-bis (organic peroxide thermal polymerization initiator) t-butylperoxycarbonyloxy) hexane (hereinafter abbreviated as “tBCH”) [1 minute half-life temperature is 150 ° C. ] Weighed and mixed in the order of 1.3 parts to obtain a liquid raw material.

Next, 79.8 parts of the above (meth) acrylic acid ester polymer, 142 parts of expanded graphite powder (trade name “EC-50”, manufactured by Ito Graphite Industries Co., Ltd., average particle size: 250 μm), carbon black (Product name “EC”, manufactured by Ketjen Black International Co., Ltd., number density: 100 to 145 kg / m ² ) 1.7 parts and the liquid raw material are put in a Hobart container in the order listed, The mixture was defoamed with stirring and mixing to obtain a heat conductive pressure-sensitive adhesive composition. The raw materials used are shown in Table 1. The mixing was performed according to the following conditions using a Hobart mixer (trade name “ACM-5LVT type, capacity: 5 L”) manufactured by Kodaira Seisakusho.
Mixing conditions:
Using a thermostatic bath (trade name “Viscomate 150III”, manufactured by Toki Sangyo Co., Ltd.), the temperature control of the Hobart container was set to 60 ° C.
1. 1. Mix in the rotation speed memory 3 × 10 minutes 2. Mix in the rotation speed memory 5 × 10 minutes Rotation speed memory 3 × 10 minutes, mixing while vacuum degassing at -0.1 MPa

Thereafter, the thermally conductive pressure-sensitive adhesive composition is sandwiched between release PETs and pressed from above the release PET with a roll to form a thermally conductive pressure-sensitive adhesive composition into a sheet having a thickness of 1000 μm, and 150 ° C. Polymerization was carried out in a hot air oven for 20 minutes to obtain a sheet (X1) whose both surfaces were covered with release PET.
When the polymerization conversion rate of the (meth) acrylic acid ester monomer mixture was calculated from the amount of residual monomers in the sheet (X1), it was 99.9%.

(Sheet (X2))
A sheet (X2) having both surfaces covered with release PET was obtained in the same manner as the sheet (X1) except that the expanded graphite powder content was 356 parts. The raw materials used are shown in Table 1.

(Sheet (X3))
A sheet (X3) whose both surfaces were covered with release PET was obtained in the same manner as the sheet (X1) except that the expanded graphite powder content was 712 parts. The raw materials used are shown in Table 1.

(Sheet (X4))
Isoprene homopolymer terminal hydroxyl group-modified liquid product (trade name “PP-IP”, manufactured by Idemitsu Kosan Co., Ltd.) 89.7 parts and polyurethane (trade name “PU-330”, manufactured by Hirono Scientific Co., Ltd.) 10.3 The carbon black (trade name “EC”, manufactured by Ketjen Black International Co., Ltd., number density: 100 to 145 kg / m ² ) 2.0 parts and expanded graphite 160 parts of the powder was put into a Hobart container and defoamed for 10 minutes with stirring and mixing under reduced pressure to obtain a heat conductive pressure-sensitive adhesive composition. Other steps were the same as in the sheet (X1), and a sheet (X4) having both surfaces covered with release PET was obtained. The raw materials used are shown in Table 1.

(Sheet (X5))
In the same manner as in the sheet (X1), except that 142 parts of limpen-like graphite (trade name “W-5”, manufactured by Ito Graphite Industries Co., Ltd., average particle size: 5 μm) was used instead of the expanded graphite powder. A sheet (X5) covered with release PET was obtained. The raw materials used are shown in Table 1.

(Sheet (Y1))
Without using expanded graphite and carbon black, the amount of (meth) acrylic acid ester polymer, 2EHA, MAA, polyfunctional monomer, and tBCH was changed, and others were the same as in the sheet (X1). A heat conductive pressure sensitive adhesive composition was obtained. The raw materials used are shown in Table 2. When the obtained heat conductive pressure-sensitive adhesive composition was formed into a sheet shape, both sides were made of release PET in the same manner as the sheet (X1) except that the thickness of the sheet was changed from 1000 μm to 50 μm. A covered sheet (Y1) was obtained.

(Y1 ')
A sheet (Y1 ′) having both surfaces covered with release PET was obtained in the same manner as the sheet (Y1) except that the thickness was changed to 500 μm. The raw materials used are shown in Table 2.

(Y1 '')
A sheet (Y1 ″) having both surfaces covered with release PET was obtained in the same manner as the sheet (Y1) except that the thickness was changed to 1000 μm. The raw materials used are shown in Table 2.

(Y2)
Except for further using 129 parts of aluminum hydroxide (trade name “BF083”, manufactured by Nippon Light Metal Co., Ltd., average particle size: 8 μm) when obtaining the heat conductive pressure-sensitive adhesive composition, the same procedure as in the sheet (Y1) was performed. Then, a sheet (Y2) having both surfaces covered with release PET was obtained. The raw materials used are shown in Table 2.

(Y3)
95.2 parts of isoprene homopolymer terminal hydroxyl group-modified liquid (trade name “PP-IP”, manufactured by Idemitsu Kosan Co., Ltd.) and polyurethane (trade name “PU-330”, manufactured by Hirono Scientific Industries Co., Ltd.) 4.8 Were put in a Hobart container and defoamed with stirring and mixing under reduced pressure to obtain a heat conductive pressure-sensitive adhesive composition. The raw materials used are shown in Table 2. The mixing conditions are the same as those for the sheet (X1). In the same manner as the sheet (Y1), the obtained heat conductive pressure-sensitive adhesive composition was used to obtain a sheet (Y3) whose both surfaces were covered with release PET.

<Examples 1-8 and Comparative Examples 1-5>
Sheets (X1), (X2), (X3), (X4), (X5), (Y1), (Y1 ′), (Y1 ″), (Y2), and (Y3) produced as described above ), And aluminum sheets and graphite sheets, heat conductive pressure-sensitive adhesive sheets (F1) to (F8) according to Examples 1 to 8, and heat conductive pressure-sensitive adhesive sheets (FC1) according to Comparative Example 1. ) And Comparative Examples 2 to 5 were prepared as heat conductive pressure-sensitive adhesive laminated sheets (FC2) to (FC5). Tables 3 and 4 show the combinations of sheets used. In addition, about the sheet | seat concerning a comparative example, the layer equivalent to A layer of the heat conductive pressure-sensitive-adhesive laminated sheet concerning an Example is set as C layer, the layer equivalent to B1 layer is set as D1 layer, and is equivalent to B2 layer. The layer was a D2 layer.

Example 1
In the heat conductive pressure-sensitive adhesive laminated sheet (F1) according to Example 1, the sheet (X1) was used as the A layer, and the sheet (Y1) was used as the B1 layer and the B2 layer. That is, the sheet (X1) and the sheet (Y1) were overlapped, and the sheet (X1) and the sheet (Y1) were pressure-bonded so that air was not mixed. After that, another sheet (Y1) was superposed on the side of the sheet (X1) where the sheet (Y1) was not laminated, and the sheet (Y1) was pressure-bonded. The release PET was peeled off before each layer was overlaid.

(Examples 2 to 8)
The heat conductive pressure-sensitive adhesive laminated sheets (F2) to (F8) according to Examples 2 to 8 are formed on one surface side of the A layer using the sheets shown in Table 3 in the same manner as the sheet (F1). After laminating the B1 layer, the B2 layer was laminated on the other surface side. Note that, similarly to the sheet (F1), the sheets (F2) to (F8) used layers having the same composition for the B1 layer and the B2 layer.

(Comparative Example 1)
The heat conductive pressure-sensitive adhesive sheet (FC1) according to Comparative Example 1 was composed only of the sheet (X1).

(Comparative Example 2)
The heat conductive pressure-sensitive adhesive laminated sheet (FC2) according to Comparative Example 2 is the same as the heat conductive pressure-sensitive adhesive laminated sheet (F1) except that an aluminum sheet is used as the C layer.

(Comparative Example 3)
The heat conductive pressure-sensitive adhesive laminated sheet (FC3) according to Comparative Example 3 is the same as the heat conductive pressure-sensitive adhesive laminated sheet (F1) except that a graphite sheet is used as the C layer.

(Comparative Example 4)
The heat conductive pressure-sensitive adhesive laminated sheet (FC4) according to Comparative Example 4 is the same as the laminated sheet (F1) except that the sheet (X5) is used as the C layer.

(Comparative Example 5)
In the heat conductive pressure-sensitive adhesive laminated sheet (FC5) according to Comparative Example 5, the sheet (Y1) was laminated only on one surface side of the sheet (X3) by the same method as the sheet (F1).

<Performance evaluation>
The evaluation results of the sheets (F1) to (F8) produced in the examples are shown in Table 3, and the evaluation results of the sheets (FC1) to (FC5) produced in the comparative examples are shown in Table 4. In addition, "-" in the table indicates that the other items of measurement results have already been out of specification for use as a heat conductive pressure-sensitive adhesive (laminate) sheet, so that the item is not evaluated. means.

  As shown in Table 3, all the laminated sheets according to the examples were excellent in insulation (surface resistance), adhesion, and thermal conductivity (thermal characteristics), and no delamination was observed. On the other hand, as shown in Table 4, the sheet (FC1) of Comparative Example 1 which is a single layer was inferior in insulation. In the sheet (FC2) of Comparative Example 2, layers made of a resin were laminated on both surfaces of a metal (aluminum) sheet, and the flexibility of each layer was different, so peeling between layers was observed. Moreover, the said sheet | seat was inferior to a softness | flexibility, and its adhesiveness was inferior. In the sheet of Comparative Example 3 (FC3), layers made of a resin were laminated on both sides of a graphite sheet, and since the flexibility of each layer was different, peeling between layers was observed. Moreover, the said sheet | seat was inferior to a softness | flexibility, and its adhesiveness was inferior. In the sheet (FC4) of Comparative Example 4 in which the sheet (X5) using phosphorus pen-like graphite instead of the expanded graphite powder was used for the C layer, the thermal characteristics were inferior. In Comparative Example 5 in which the sheet (Y1) was laminated only on one side of the sheet (X3) but no sheet was on the other side, the expanded graphite powder from the laminated sheet (FC5) As a result, it was difficult to obtain a stable laminated sheet.

<Reduction of surface temperature to equipment with light emitting diode (LED) light source>
Example 9
The commercially available LED lighting (Hitachi Lighting Co., Ltd./LES7L/K6N-A) was disassembled, and the sheet (F1) used in Example 1 was cut into a size of 60 cm × 60 cm on the back side of the substrate on which the LED chip was mounted. After pasting and reassembling, it was lit again. The surface temperature (referred to as “LED surface temperature”) of the diffusion plate on the LED chip 60 minutes after the LED lighting was turned on was measured by thermovision. The results are shown in Table 5.

(Comparative Example 6)
Evaluation was performed in the same manner as in Example 9 except that the sheet (F1) was not used. The results are shown in Table 5.

(Comparative Example 7)
Evaluation was performed in the same manner as in Example 9 except that a single layer sheet of 60 cm × 60 cm and 0.5 W / m · K was used instead of the sheet (F1). The results are shown in Table 5.

In Example 9 using the laminated sheet (F1) of the present invention, a reduction in the LED surface temperature was achieved, and the LED surface temperature could be lowered by 6 ° C. compared to the case where no sheet was used (Comparative Example 6). It was.
On the other hand, in Comparative Example 7 using a single layer sheet of 0.5 W / m · K, the LED surface temperature decreased only 1 ° C. as compared to the case where the sheet was not used (Comparative Example 6).

  Although the present invention has been described in connection with the most practical and preferred embodiments at the present time, the present invention is not limited to the embodiments disclosed herein, The present invention can be changed as appropriate without departing from the gist or concept of the invention that can be read from the claims and the entire specification, and the heat conductive pressure-sensitive adhesive laminate sheet and electronic component accompanying such changes are also within the technical scope of the present invention. Must be understood as encompassed by.

Claims (7)

An A layer composed of a thermally conductive pressure-sensitive adhesive composition (E1) containing at least one polymer (S1) selected from the group consisting of rubber, elastomer and resin;
A B1 layer comprising a thermally conductive pressure-sensitive adhesive composition (E2) comprising at least one polymer (S2) selected from the group consisting of rubber, elastomer and resin, laminated on one surface side of the A layer; ,
A B2 layer comprising a thermally conductive pressure-sensitive adhesive composition (E3) comprising at least one polymer (S3) selected from the group consisting of rubber, elastomer and resin, laminated on the other surface side of the A layer; ,
A heat conductive pressure-sensitive adhesive laminate sheet (F). The heat conductive pressure-sensitive-adhesive laminated sheet of Claim 1 in which the said A layer contains 30 to 800 mass parts expanded graphite powder (B) with respect to 100 mass parts of said polymers (S1). (F). The heat conductive pressure-sensitive-adhesive laminated sheet (F) of Claim 1 or 2 whose thickness of the said B1 layer and the said B2 layer is 1 micrometer or more and 1500 micrometers or less. The polymer (S1) is a (meth) acrylic acid ester polymer (A1), the polymer (S2) is a (meth) acrylic acid ester polymer (A2), and the polymer (S3) is ( The heat conductive pressure-sensitive-adhesive laminated sheet (F) according to any one of claims 1 to 3, which is a (meth) acrylic acid ester polymer (A3). The (meth) acrylic acid ester polymer (A1) is obtained by polymerizing the (meth) acrylic acid ester monomer (α1) in the presence of the (meth) acrylic acid ester polymer (AP1). The (meth) acrylic acid ester polymer (A2) is obtained by polymerizing the (meth) acrylic acid ester monomer (α2) in the presence of the (meth) acrylic acid ester polymer (AP2). Yes, the (meth) acrylic acid ester polymer (A3) is obtained by polymerizing the (meth) acrylic acid ester monomer (α3) in the presence of the (meth) acrylic acid ester polymer (AP3) The heat conductive pressure-sensitive-adhesive laminated sheet (F) of Claim 4 which is. The electronic component provided with the heat conductive pressure-sensitive-adhesive sheet (F) in any one of Claims 1-5. Equipment with electroluminescence (EL), light emitting diode (LED) light source, automotive power device, fuel cell, solar cell, battery, mobile phone, personal digital assistant (PDA), notebook computer, liquid crystal, surface conduction electron-emitting device The electronic component according to claim 6, wherein the electronic component is a display (SED), a plasma display panel (PDP), or an integrated circuit (IC).