| 摘要 |
PROBLEM TO BE SOLVED: To obtain a heat-shrinkable film improved in dimensional stability, spontaneous shrinking, and shrinking properties by specifying the heat shrinkage in the stretching direction of a transversely monoaxially stretched film in a specified temp. range to a value given by a specific equation or higher. SOLUTION: A styrenic resin is extruded at 150-250 deg.C, pref. 170-220 deg.C, into a flat or tubular shape and then monoaxially stretched at 60-120 deg.C, pref. 80-110 deg.C, in the longitudinal and/or transverse direction by 1.5-8 times, pref. 2-6 times, thus giving a styrenic heat-shrinkable film of which the heat shrinkage in the transverse stretching direction at 50-60 deg.C has a value given by the equation: S=0.03T<2> -2.85T+68 [wherein S is heat shrinkage (%); and T is shrinking temp. ( deg.C)] or lower; the heat shrinkage in the transverse dirction at 70-90 deg.C has a value given by the equation: S=175.5×1nT-730 or higher; the spontaneous shrinkage is 0-2.0 wt.%; the heat shrinkage in the direction vertical to the stretching direction at 80 deg.C is 15% or lower, pref. 10% or lower; and the thickness is 10-300μm, pref. 30-100μm.
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