PURPOSE: To obtain superior shrink characteristics by a method wherein a shrink film is made of a crystalline polyester and has specific values of minimum thermal shrinkage factor and maximum thermal shrinkage stress in a film surface after it is treated at a specific temperature for a specific time.

CONSTITUTION: A shrink film is made of a crystalline polyester and has a minimum thermal shrinkage factor of 20-90% in a film surface after it is treated for 30sec under a 100°C atmosphere and a maximum thermal shrinkage stress of 5.0×104-5.0×106Pa in a film surface after it is treated for 30sec under a 100°C atmosphere. If a thermal shrinkage factor is less than 20%, a thermal shrink amount required for a thermal shrink film is not sufficient. A draw ratio of 10 or more is required for a shrink film to obtain a thermal shrinkage factor more than 90%, and such a film is difficult to produce. If a thermal shrinkage stress is less than 5.0×104Pa, the adhesive force of the film to a container or the like by shrinking is reduced. If a thermal shrinkage stress is more than 5.0×106Pa, a matrix, such as a plastic bottle or an aluminum container, may be deformed when the film is thermally shrunk to adhere to the matrix.