Patent ID: 9359537
Filing Date: 2016-06-07
CPC Classification: C08F,C08L,C09J

Claim Text:
1. A block copolymer composition for as viscous adhesive comprising: a component (a): more than 80 mass % and 90 mass % or less of a block copolymer having a number average molecular weight of 30,000 or more and 60,000or less, comprising a polymer block (A) mainly including a vinyl aromatic monomer unit and a polymer block (B) mainly including a conjugated diene monomer unit selected from the group consisting of 1,3-butadiene, 2,3-dimethy 1,3-butadiene, 1,3-pentadiene, and 3-hexacliene; and a component (b): 10 mass % or more and less than 20 mass % of a block copolymer having a number average molecular weight of more than 120,000 and 200,000 or less comprising a polymer block (A) mainly including a vinyl aromatic monomer unit and a polymer block (B) mainly including a conjugated diene monomer unit selected from the group consisting of 1,3- butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and 1,3-hexadiene; a content of the vinyl aromatic monomer unit being 25 to 50 mass %; the composition having a 15 mass % toluene solution viscosity of 10 to 40 mPas; and a number average molecular weight ratio of the component (b) to the component (a) being 2.0 to 4.0.