JP3212106B2 - High thermal conductive laminate and heat radiating sheet made using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat dissipating laminate, and more particularly, to a heat dissipating laminate having excellent heat conductivity and flexibility, which can be formed into a sheet or a cylinder. And a heat radiation sheet produced using the same.

[0002]

2. Description of the Related Art Since heat generated during use of an electronic component may cause problems such as deterioration of characteristics and breakage of the component, a radiator having an increased cooling efficiency such as a heat sinker in a heat-generating portion. Is installed. In this case, a mica sheet, a polymer film, or the like is used at a contact portion between the component and the heat sinker for electrical insulation and for enhancing adhesion and reducing thermal resistance. However, the former has poor mechanical strength, and the latter has poor thermal conductivity, so that an adhesive sheet having more excellent properties is required. For this reason, silicone rubber and other organic rubber containing a thermally conductive fine powder filler have been proposed. In this case, a metal oxide which is generally advantageous in cost is used as the heat conductive filler, but in order to further improve the characteristics, a boron nitride powder having a large amount of the filler and a large heat conductivity is used. Proposals such as have been made.

[0003]

However, even if the amount of the filler is increased or a filler having a high thermal conductivity is used, a resin layer is formed at the interface between the fillers, and the contact between the fillers partially occurs. And it is difficult to obtain high thermal conductivity.

Accordingly, an object of the present invention is to provide a high thermal conductive laminate having high thermal conductivity and a sheet produced using the laminate.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found that the following laminate has high thermal conductivity, and that the laminate has excellent characteristics. It has been found that a heat dissipation sheet can be manufactured, and the present invention has been completed.

That is, a laminate formed by laminating a sheet made by impregnating or applying a thermosetting resin having a heat deformation temperature in the range of −130 ° C. to 130 ° C. on a cloth woven with metal fibers, Further, as another invention, impregnated or coated with a thermosetting resin having a heat deformation temperature in a range of −130 ° C. to 130 ° C., on a cloth woven with elastic fibers as warp and metal wire as weft. It has been found that a laminate formed by laminating the sheets prepared in such a manner that the metal wires are aligned in the same direction has extremely high heat radiation characteristics.

Further, a heat radiating sheet produced by cutting these laminates so that a metal wire is perpendicular to the sheet plane has a higher heat conduction characteristic than a heat radiating sheet formed of a resin and a filler. I found that.

Further, as another invention, a heat-dissipating sheet produced by cutting these high-thermal-conductivity laminates so that a metal wire is perpendicular to the sheet plane is provided on both sides of an insulating material having excellent thermal conductivity. By sticking the sheet and making it,
It has been found that a heat dissipation sheet having excellent insulation properties can be produced.

[0009]

Normally, in a composition comprising a resin and a thermally conductive filler, a structure in which a filler having a high thermal conductivity is connected as long as possible in the resin composition is required in order to improve the thermal conductivity. For this purpose, it is necessary to use a filler having a long shape, or to use the fillers as closely as possible. In the present invention,
Since the metal wires are woven at regular intervals and one metal wire is continuous, heat conduction can be performed extremely well unless the metal wire is cut. Furthermore, since fibers rich in elasticity are present between the metal wires and are laminated so as to be orthogonal to each other, sufficient strength is obtained, and cutting of the metal during molding becomes a very difficult structure. ing.

[0010] The metal wire that can be used in the present invention is not particularly limited as long as it has high thermal conductivity. For example, a single metal such as copper, iron and aluminum, an alloy such as brass and white copper, etc. Can be used.

The elastic fibers used in the present invention include tetron, nylon, polyester, polyethylene phthalate, polypropylene, polyethylene, cellulose, acrylic and the like. The diameter of these metal wires and fibers is 1
Within the range of 0-1000 microns, preferably 20-5
It is better to use 00 micron fibers and metal wires. If these diameters are less than 10 microns, the cutting of the metal wires tends to occur particularly when weaving the cloth. On the other hand, if it exceeds 1000 microns, the metal wire becomes thick, and the elasticity of the laminate decreases.

The heat distortion temperature used in the present invention is -130 ° C.
The thermosetting resin in the range from to 130 ° C. includes silicone rubber, urethane rubber, butadiene rubber,
Ethylene propylene rubber, sulfur, organic peroxide,
A rubber-like thermosetting resin composed of a curing agent such as a metal oxide can be used. In particular, from -130 ° C to 130
Use of synthetic rubber, which has a heat deformation temperature at which mechanical properties such as elastic modulus rapidly changes in the temperature range of ℃, is particularly useful when used as a heat dissipation sheet because it is particularly excellent in contact with electronic components that require cooling. It is. As such a resin composition, a polyolefin polyol comprising a hydrogenated product of a polyhydroxybutadiene polymer as a main component, and a polyolefin obtained by a polyfunctional isocyanate having 1.5 or more isocyanate groups in a molecule as a curing agent thereof Appropriate selection of polyester-based urethane elastomer or polyester-based urethane elastomer obtained by the above-mentioned polyfunctional isocyanate with polyester polyol having a molecular weight of 2,000 or more, and further, polyether-based urethane elastomer obtained by the above-mentioned polyfunctional polyol with molecular weight of 2,000 or more and the above-mentioned polyfunctional isocyanate Can be used. Among the resin compositions, a polyolefin-based urethane elastomer is most preferred. As the curing agent for the elastomer, any one having at least 1.5 isocyanate groups in the molecule can be used, and hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate,
Isophorone diisocyanate, xylylene diisocyanate, and the like, and compounds derived therefrom can be used. It is preferable to mix the curing agent and the base agent with the isocyanate in the range of 0.7 to 1.1 (functional group ratio) with respect to the hydroxyl group of the polyol in order to obtain optimum physical properties.

In the present invention, a fabric woven with a metal wire or a fabric woven with elastic fibers as warp yarns and a metal wire as weft yarns has a heat deformation temperature of -130 ° C to 13 ° C.
When laminating sheets produced by impregnating or applying a thermosetting resin having a temperature range of up to 0 ° C., it is necessary to laminate the sheets so that the metal wires are aligned in the same direction.
By laminating in this way, a laminate having extremely high thermal conductivity can be manufactured.

Further, in the present invention, a sheet is produced by cutting the laminate obtained above to a thickness of about 0.5 to 10 mm on a plane perpendicular to the metal wires. It has a very high thermal conductivity. Further, by attaching an insulating sheet having excellent thermal conductivity to both sides of the sheet thus produced, electrical insulation can be imparted. These heat-dissipating sheets are useful as heat-conducting sheets for electronic components and heat-dissipating plates.

Further, the sheet obtained by the present invention can be formed not only by lamination but also by winding it around a support rod to form a cylindrical structure. In this case, the sheet is wound to form a cylinder, and 0.5 is applied in the vertical direction of the cylinder in the same manner as described above.
By cutting to a thickness of about 10 to 10 mm, an O-ring or the like having excellent thermal conductivity can be manufactured.

The sheet obtained by the present invention can be used not only for heat dissipation but also as a vibration damping material.
By energizing, it can be used as a heat generating sheet as a flexible heating element.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments, but the present invention is not limited to these embodiments and is not limited thereto. Example 1 A plain woven fabric was produced using polyethylene terephthalate having a fiber diameter of 60 microns as a warp and a copper wire of 80 microns as a weft.

On the other hand, a hydrogenated product of polyhydroxy-1,4-butadiene polymer [Polytail H, manufactured by Mitsubishi Kasei KK,
(Hydroxyl value 45) was sufficiently stirred at 90 ° C. for 30 minutes at atmospheric pressure. Further, in order to remove water in the resin, stirring was continued for 60 minutes under a reduced pressure of about 1 Torr, then the pressure was once returned to atmospheric pressure, 6.5 g of 2,4-toluene diisocyanate was added, and the mixture was stirred for 5 minutes. Cooled immediately to room temperature.

The obtained solid is passed through a three-roll mill three times,
Mix well. 400 g of toluene was added to 200 g of the mixture to obtain a solution of the mixture.

The plain woven fabric obtained above was impregnated with this solution, and the solvent was volatilized at 80 ° C. 300 prepregs thus obtained were superposed on each other so that the metal wires were perpendicular to each other, and kept at 130 ° C. for 2 hours by a hot press at a pressure of 10 kg / cm ² .

By this operation, a laminate of about 20 mm was obtained. The laminate was cut at a distance of about 2 mm in a direction perpendicular to the press surface while using cooling water. The properties of the prepared sheet were measured, and the following values were obtained. Thermal conductivity 55 × 10 ^-3 cal / ° C · sec · cm Thermal resistance 0.075 ° C / W

Example 2 A plain woven fabric was prepared using 80-micron copper wires as warp and weft. On the other hand, 100 g of a hydrogenated polyhydroxy-1,4-butadiene polymer [Polytail H, hydroxyl value 45, manufactured by Mitsubishi Chemical Corporation] was sufficiently stirred at 90 ° C. for 30 minutes at atmospheric pressure. Further, in order to remove water in the resin, stirring was continued for 60 minutes under a reduced pressure of about 1 Torr, and then the pressure was once returned to the atmospheric pressure, and 6.5 g of 2,4-toluene diisocyanate was obtained.
Was added and stirred for 5 minutes and immediately cooled to room temperature.

The obtained solid is passed through a three-roll mill three times,
Mix well. 400 g of toluene was added to 200 g of the mixture to obtain a solution of the mixture.

The plain woven fabric obtained above was impregnated with this solution, and the solvent was evaporated at 80 ° C. 300 prepregs thus obtained were superposed on each other so that the metal wires were perpendicular to each other, and kept at 130 ° C. for 2 hours by a hot press at a pressure of 10 kg / cm ² .

By this operation, a laminate of about 20 mm was obtained. The laminate was cut at a distance of about 2 mm in a direction perpendicular to the press surface while using cooling water. The properties of the prepared sheet were measured, and the following values were obtained. Thermal conductivity 75 × 10 ^-3 cal / ° C · sec · cm Thermal resistance 0.035 ° C / W

Example 3 A plain woven fabric was prepared by using nylon having a fiber diameter of 50 μm as the warp and copper wire of 60 μm as the weft. Silicone resin KE133T-U (Shin-Etsu Chemical Co., Ltd.) 10
0 g and bis-2,4-dichlorobenzoyl peroxide (1.6 g) were mixed and dissolved in xylene (200 g). A laminate was obtained in the same manner as in Example 1, and a sheet was produced in the same manner. The properties of the obtained sheet are as follows. Thermal conductivity 68 × 10 ⁻³ cal / ° C. · sec · cm Thermal resistance 0.063 ° C./W

Example 4 A plain woven fabric was produced by using an acrylic fiber having a fiber diameter of 60 μm as the warp and an aluminum wire of 80 μm as the weft. 99 g of polyether olefin (having a hydroxyl value of 54) and 1 g of glycerin produced by the reaction of bisphenol A and propylene oxide were charged into a vacuum heating stirrer, and sufficiently stirred at 90 ° C. for 30 minutes at atmospheric pressure. Stirring was performed in the same manner as in Example 1, and xylylene diisocyanate 1
1.5 g was added, stirred for 5 minutes and immediately cooled to room temperature.

A sheet was prepared in the same manner as in Example 1, and the characteristics of the sheet were measured. Thermal conductivity 53 × 10 ^-3 cal / ° C · sec · cm Thermal resistance 0.072 ° C / W

Example 5 A prepreg was prepared from the plain woven fabric prepared in Example 1 using the resin liquid used in Example 1. The obtained prepreg was wound around a support rod having a diameter of 20 mm in the direction of elastic fibers. The support bar was heated at 130 ° C. for 4 hours and removed from the support bar while it was hot, to produce a cylinder. This cylinder was cut in the vertical direction to a thickness of about 2 mm to produce an O-ring having excellent thermal conductivity. The characteristics were measured in the same manner as in Example 1, and the following values were obtained. Thermal conductivity 48 × 10 ^-3 cal / ° C · sec · cm Thermal resistance 0.095 ° C / W

Example 6 Hydrogenated product of polyhydroxy-1,4-butadiene polymer [Polytail H, hydroxyl value 45, manufactured by Mitsubishi Kasei Co., Ltd.] 10
0 g, 6.5 g of 2,4-toluene diisocyanate and 400 g of an alumina filler were sufficiently mixed to produce a heat conductive sheet of about 0.2 mm. The resulting heat conductive sheet was attached to both sides of the sheet prepared in Example 2 to prepare a heat radiating sheet having excellent insulation properties. The properties of the prepared sheet were as follows. Thermal conductivity 60 × 10 ⁻³ cal / ° C. · sec · cm Thermal resistance 0.067 ° C./W Volume resistivity 3.4 × 10 ¹⁴ Ω · cm

[0031]

The heat-conductive laminate of the present invention comprises a fabric woven from metal fibers or a fiber having high elasticity as warp yarns,
Since the structure uses a cloth woven with metal wires as weft yarns, the heat dissipation sheet made from the high thermal conductive laminate has a high thermal conductivity, so that the temperature of the heating element such as electronic components can be reduced, Is effective in reducing the size and lengthening the life of the device.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shigeru Kubota 8-1-1 Tsukaguchi Honcho, Amagasaki City Inside Materials Research Laboratory, Mitsubishi Electric Corporation (72) Inventor Yuji Hizuka 8-1-1 Tsukaguchi Honcho Amagasaki City Mitsubishi Electric Corporation Materials Research Laboratory (72) Inventor Kigen Moriwaki 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Corporation Materials Research Laboratory (72) Inventor Masao Fujii 8-1-1 Tsukaguchi Honcho Amagasaki City (72) Inventor Masaaki Murakami 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Corporation Central Research Laboratory (72) Inventor Tetsuro Ogushi 8-1-1 Tsukaguchi Honcho Amagasaki City (56) References JP-A-60-92839 (JP, A) JP-A-58-18249 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B32B 5/00-5/32 H05K 7/20

Claims (4)

(57) [Claims] 1. A fabric woven with a metal wire has a heat distortion temperature of-
Polyhydroxy in the range from 130 ° C. to 130 ° C.
Polyolefin consisting of hydrogenated butadiene polymer
Polyol is used as a main component, and as a curing agent, 1.
Polyfunctional isocyanate having 5 or more isocyanate groups
-Polyolefin-based urethane elastomer obtained by
Mer, polyester polyol having a molecular weight of 2,000 or more
And polyester obtained by the polyfunctional isocyanate
Urethane elastomer and molecular weight of 2000 or more
Polyetherpolyol and the polyfunctional isocyanate
Polyether urethane elastomers obtained from
Heat radiation of a high thermal conductive laminate made by laminating sheets made by impregnating or applying a thermosetting resin selected from the group consisting of
Wood . 2. A cloth woven with elastic fibers as warp yarns and metal wires as weft yarns, and has a heat deformation temperature of -130 ° C.
Polyhydroxybutadier in the range up to 130 ° C
Polyolefin comprising hydrogenated polymer
As the main agent and 1.5 or more in the molecule as its hardener
A polyfunctional isocyanate having an isocyanate group of
Polyolefin urethane elastomer obtained
Polyester polyol having a molecular weight of 2,000 or more
Polyester based urethane obtained from functional isocyanate
Tan elastomers and polyethers with a molecular weight of 2,000 or more
Terpolyol and the above-mentioned polyfunctional isocyanate
Consisting of polyether-based urethane elastomers
A highly heat conductive laminate heat radiating material obtained by laminating sheets prepared by impregnating or applying a thermosetting resin selected from the group consisting of metal wires arranged in the same direction. 3. A heat-dissipating sheet produced by cutting the highly heat-conductive laminate according to claim 1 so that a metal wire is perpendicular to a sheet plane. 4. An insulating sheet having excellent thermal conductivity on both surfaces of a heat-dissipating sheet produced by cutting the highly heat-conductive laminate according to claim 1 so that a metal wire is perpendicular to a sheet plane. A heat dissipation sheet made by sticking a sheet.