Abstract: [PROBLEMS] Disclosed is a heat shrinkable film having excellent heat resistance, content resistance, impact resistance, low/high temperature cycle resistance, and abrasion resistance. [MEANS FOR SOLVING PROBLEMS] Specifically disclosed is a heat shrinkable film comprising an intermediate layer (1), a front surface layer (2) and a back surface layer (3) so arranged as to sandwich the intermediate layer (1), and an overcoat layer (4) arranged on top of the front surface layer (2). The intermediate layer (1) contains first cyclic olefin resin and a random copolymer of ethylene and another ?-olefin or a random copolymer of propylene and another ?-olefin. The front surface layer (2) and the back surface layer (3) respectively contain second cyclic olefin resin and linear low-density polyethylene resin. Such a multilayer heat shrinkable film is formed into a tubular shape in such a manner that the overcoat layer (4) is on the outside.

Abstract: A multi-layered heat-shrinkable film composed of at least three layers has: front-back film layers each composed of a resin composition having cyclic olefin-based resin of from 55 to 95 mass % and linear low-density polyethylene of from 45 to 5 mass %; and an intermediate film layer composed of a resin composition having propylene-?-olefin random copolymer of from 95 to 55 mass % and cyclic olefin-based resin of from 5 to 45 mass %, or composed of a resin composition having: a resin composition of from 95 to 55 mass % mainly composed of the propylene-?-olefin random copolymer; and the cyclic olefin-based resin of from 5 to 45 mass % When immersed in a hot water of 90° C. for 10 seconds, the multi-layered heat-shrinkable film has a heat shrinkage in a lateral direction of 50% or higher, and has a tear propagation strength in a longitudinal direction of from 800 mN to 350 mN.

Abstract: The present invention provides a heat shrinkable film comprising at least one layer of a thermoplastic resin and having a heat shrinkage in the main orientation direction of 10% or less after treatment in a hot water at 70° C. for 2 seconds, and 65% or more after treatment in hot water at 90° C. for 10 seconds, the heat shrinkable film preferably having a natural shrinkage in the main orientation direction of 2.5% or less after being allowed to stand at 40° C. for 7 days.

Abstract: The present invention provides a low temperature heat shrinkable film for labeling comprising at least one layer of a thermoplastic resin, in whose correlation diagram showing the relation between the heat shrinkage percentage Y at 80° C. in one direction and the heat shrinkage time t (1≦t≦5), the gradient Y′ is in an area between the gradients satisfying Equations 1 and 2 and the heat shrinkage percentage Y is in an area between the heat shrinkage percentages satisfying Equations 3 and 4: Y′=−1.05t2+12.05t  (Equation 1) Y′=−0.30t2+2.90t  (Equation 2) Y=−1.05t2+12.05t+40  (Equation 3) Y=−0.30t2+2.

Abstract: A process for preparing a substantially particulate polyvinyl alcohol having a high degree of polymerization of which a 4% by weight aqueous solution has a viscosity at 20.degree. C. of not less than 80 cps, which comprises hydrolyzing a substantially particulate polyvinyl ester having a high degree of polymerization in an alcohol containing an alkali catalyst in heterogeneous system. According to the process of the present invention, there can be easily produced a substantially particulate polyvinyl alcohol having high degree of polymerization, which has the high bulk density and the excellent powder flowability.