| abstract |
PURPOSE:A hot melt adhesive which has a high initial tack to an adherend and good balance between bonding and peeling and can withstand high-speed bonding, comprising a specified copolyester. CONSTITUTION:A copolyester obtained by reacting an acid component comprising 80-97mol% terephthalic acid and 20-3mol% isophthalic acid with a diol component containing 60-80mol% 1,4-butanediol, 40-20mol% diethylene glycol and, optionally, a glycol (e.g., ethylene glycol) and having a reduced viscosity of 0.8-1.4dl/g and an m.p. of 160-200 deg.C is formed into a hot melt adhesive comprising a copolyester film having a heat of fusion of crystals of 5-10Cal/g, a haze of 5-35%, an initial Young's modulus at 22 deg.C of 3X10<3>-30X10<3>kg/cm<2>, and a thickness of 40-200mum. |