THERMALLY SHRINKABLE FILM

PURPOSE:To obtain thermally shrinkable film that is composed of (co)polymer of polymerization units shown by the specific formula, has a specific gel fraction and a thermal shrinkage degree, is excellent in heat sealability and heat resistance in a thermally shrink packaging time and is able to obtain a good packaging form. CONSTITUTION:The titled film thermally shrinkable that is composed of (co) polymer (such as PE, ethylene/vinyl acetate copolymer, ethylene/alpha-olefin copolymer, PP, PS, acryl resin, PVC, etc.) of polymerization units of the Formula wherein: R1 represents H, halogen, alkyl, acetyl, acrylyl, phenyl, OH; n is an integer indicating a polymerization degree) and has gel fraction 10-40%, thermal shrinkage degrees 10-90%. Specified electron rays are irradiated to synthetic resin film having no thermal shrinkability to allow the film to be crosslinked nearly over the whole zone in the thickness direction and to be stretched. By controlling the crosslinking degree in this manner, thermally shrinkable film having heat sealability and thermal shrinkability can be obtained stably.