The term ethylene-o-olefin copolymer resin having a density of 0.88-0.93 (g/cm3) and a crystalline melting point of 110???-130??? C. used in this invention means a copolymer resin of ethylene and an ??-olefin having 4-18 carbon atoms such as 1-butene, 1-pentene 4-methyl-1-pentene, 1-hexene, 1-octene or the like.