| 摘要 |
PROBLEM TO BE SOLVED: To provide a block copolymer for an adhesive, which has appropriate adhesive force and adhesiveness, can maintain stable adhesiveness for a long period of time, and exhibits adhesiveness in a similar level even under a low-temperature condition to the adhesiveness under a room temperature condition.SOLUTION: An adhesive composition is provided, which comprises a block copolymer including a polymer block (A) essentially comprising a vinyl aromatic monomer unit and a polymer block (B) essentially comprising a conjugate diene monomer unit; and the block copolymer satisfies the following conditions (1) to (5). They are: (1) the total content of the amounts of 1,2-bonds and 3,4-bonds in the conjugate diene monomer unit is 65 to 90%; (2) the content of the vinyl aromatic monomer unit is 12 to 25 mass%; (3) a hydrogenation rate in a double bond derived from the conjugate diene monomer unit of the polymer block (B) is 90% or more; (4) a melt flow rate (MFR) of the block copolymer is from 15 to 60 g/10 minutes; and (5) an order-disorder transition temperature (ODT) of the block copolymer is from 160 to 210°C. |
