Thermally conductive sheet

Patent metadata

Field	Value
Publication number	US-10040979-B2
Application number	US-201414911451-A
Country	US
Kind code	B2
Filing date	Sep 10, 2014
Priority date	Sep 13, 2013
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

A thermally conductive sheet having an adhesive layer and a non-adhesive layer laminated together. The adhesive layer contains an acrylic resin formed from an acrylic compound and a thermally conductive filler, and has a tack property higher than a tack property of the non-adhesive layer. The non-adhesive layer is formed from a resin having a glass transition temperature of 10° C. or more and at least one functional group selected from a hydroxy, a carboxyl and a glycidyl, a curing agent and a flame retardant filler. The tack property of the non-adhesive layer is from 6 to 30 kN/m 2 measured by pressing and then peeling an aluminum cylindrical probe from the non-adhesive layer with a pressing speed of 30 mm/min, peeling speed of 120 mm/min, load of 196 g, pressing time of 5.0 sec, pulling distance of 5 mm, probe heating of 40° C. and sheet stage heating of 40° C.

First claim

The invention claimed is:

1. A thermally conductive sheet in which an adhesive thermally conductive layer and a non-adhesive resin layer are laminated, wherein the adhesive thermally conductive layer contains an acrylic resin formed by curing an acrylic compound and a thermally conductive filler, and a tack property of the adhesive thermally conductive layer is higher than a tack property of the non-adhesive resin layer, and
the non-adhesive resin layer is formed from a resin having a molecular weight in terms of number average molecular weight, greater than or equal to 100,000 and less than or equal to 500,000, the resin
having a glass transition temperature greater than or equal to 10° C. and less than or equal to 110° C. and
containing at least one functional group selected from
a hydroxy group,
a carboxyl group and
a glycidyl group,

a curing agent and
a flame retardant filler, and

the tack property of the non-adhesive resin layer is from 6 to 30 kN/m2 as a probe tack measured by pressing an aluminum cylindrical probe on the non-adhesive resin layer and then peeling the aluminum cylindrical probe from the non-adhesive resin layer under conditions of pressing speed of 30 mm/min, peeling speed of 120 mm/min, load of 196 g, pressing time of 5.0 sec, pulling distance of 5 mm, probe heating of 40° C. and sheet stage heating of 40° C.

2. The thermally conductive sheet as claimed in claim 1 , wherein the flame retardant filler is an organic filler selected from a cyanuric acid compound and an organic phosphate.

3. The thermally conductive sheet as claimed in claim 1 , wherein an average particle diameter of the flame retardant filler is from 0.1 to 25 μm.

4. The thermally conductive sheet as claimed in claim 1 , wherein a heat conductivity in a thickness direction of the thermally conductive sheet is 1.5 W/m·K or more.

5. The thermally conductive sheet as claimed in claim 1 , wherein a glass transition temperature of the acrylic resin in the adhesive thermally conductive layer is from −80 to 15° C.

6. The thermally conductive sheet as claimed in claim 1 , wherein the acrylic compound forming the adhesive thermally conductive layer is a monofunctional (meth)acrylate monomer.

7. The thermally conductive sheet as claimed in claim 1 , wherein the adhesive thermally conductive layer contains from 20 to 80 parts by weight of a plasticizer and from 100 to 2,000 parts by weight of the thermally conductive filler based on 100 parts by weight of a monomer unit of the acrylic compound.

8. The thermally conductive sheet as claimed in claim 2 , wherein an average particle diameter of the flame retardant filler is from 0.1 to 25 μm.

9. The thermally conductive sheet as claimed in claim 8 , wherein a heat conductivity in a thickness direction of the thermally conductive sheet is 1.5 W/m·K or more.

10. The thermally conductive sheet as claimed in claim 8 , wherein a glass transition temperature of the acrylic resin in the adhesive thermally conductive layer is from −80 to 15° C.

11. The thermally conductive sheet as claimed in claim 8 , wherein the acrylic compound forming the adhesive thermally conductive layer is a monofunctional (meth)acrylate monomer.

12. The thermally conductive sheet as claimed in claim 8 , wherein the adhesive thermally conductive layer contains from 20 to 80 parts by weight of a plasticizer and from 100 to 2,000 parts by weight of the thermally conductive filler based on 100 parts by weight of a monomer unit of the acrylic compound.

13. The thermally conductive sheet as claimed in claim 2 , wherein a heat conductivity in a thickness direction of the thermally conductive sheet is 1.5 W/m·K or more.

14. The thermally conductive sheet as claimed in claim 2 , wherein a glass transition temperature of the acrylic resin in the adhesive thermally conductive layer is from −80 to 15° C.

15. The thermally conductive sheet as claimed in claim 2 , wherein the acrylic compound forming the adhesive thermally conductive layer is a monofunctional (meth)acrylate monomer.

16. The thermally conductive sheet as claimed in claim 2 , wherein the adhesive thermally conductive layer contains from 20 to 80 parts by weight of a plasticizer and from 100 to 2,000 parts by weight of the thermally conductive filler based on 100 parts by weight of a monomer unit of the acrylic compound.

17. The thermally conductive sheet as claimed in claim 3 , wherein a heat conductivity in a thickness direction of the thermally conductive sheet is 1.5 W/m·K or more.

18. The thermally conductive sheet as claimed in claim 3 , wherein a glass transition temperature of the acrylic resin in the adhesive thermally conductive layer is from −80 to 15° C.

19. The thermally conductive sheet as claimed in claim 3 , wherein the acrylic compound forming the adhesive thermally conductive layer is a monofunctional (meth)acrylate monomer.

20. The thermally conductive sheet as claimed in claim 3 , wherein the adhesive thermally conductive layer contains from 20 to 80 parts by weight of a plasticizer and from 100 to 2,000 parts by weight of the thermally conductive filler based on 100 parts by weight of a monomer unit of the acrylic compound.

Assignees

• Dexerials Corp

Inventors

• Sugita Junichiro

Classifications

• H10W40/251

  Organics · CPC title

• C09J2400/10

  Presence of inorganic materials · CPC title

• C09J2203/326

  for bonding electronic components such as wafers, chips or semiconductors · CPC title

• C09J7/385

  Acrylic polymers · CPC title

• C09J2413/006

  in the substrate · CPC title