Patent ID: 7105599

Claim:
A stretch material consisting essentially of a thermoplastic polymer material that meets the following conditions: (i) the thermoplastic polymer material contains: (a) 100 parts by weight of a hydrogenated block copolymer having a number average molecular weight of 50,000 to 140,000 and comprising at least two polymer blocks (A) composed mainly of a vinyl aromatic compound and at least one hydrogenated polymer block (B) composed mainly of a conjugated diene compound, wherein the amount of polymer block (A) is in the range of 10 to 40% by weight, and 50% or more of the double bonds present in the copolymer block (B) that originate from the conjugated diene compound are hydrogenated; (b) 0 to 120 parts by weight of a non-aromatic rubber softening agent; (c) 0 to 80 parts by weight of polyethylene that has an MFR of 15 g/10 min or above when measured at 190° C. under a load of 2.16 kg; and (d) 0 to 40 parts by weight of polystyrene that has an MFR of 5 g/10 min or above when measured at 200° C. under a load of 5.00 kg; (ii) the thermoplastic polymer material has a residual strain of 15% or less after having been stretched to 150% elongation at 25° C. in a stretch test; (iii) the thermoplastic polymer material has a permanent tensile set of 10% or less when the thermoplastic material is stretched to an elongation of 100%, and held in the stretched state for 120 minutes at 25° C., released and then left for 30 minutes; (iv) the thermoplastic polymer material shows a 15% or less deviation in the value of the melt tension when tested in a melt tension test performed under a temperature condition that allows an MFR of 5 to 15 g/10 min; and (v) the thermoplastic polymer material melts and breaks when wound at a winding speed of 60 m/min or more in a melt tension test performed under a temperature condition that allows an MFR of 5 to 15 g/10 min.