Heat-shrinkable polyester film

Abstract

Abstract PURPOSE:To obtain the heat-shrinkable polyester film, prominent in low temperature shrinkability as well as sealing strength and good in stability of film making, without spoiling the characteristics of polyester proper which are related to optical characteristics, banding force or the like by a method wherein crystal structure, based on the high crystallizability of polyethylene terephtalate, and the non-crystal structure of cyclohexane dimethylated copolyester are mixed in the same plane while a relation between heat-shrinkable rate as well as fusing seal strength and heat-shrinkage stress is limited within a specified range. CONSTITUTION:The film consists of 30-90wt% of polyethylene terephtalate and 10-70wt% of cyclohexane dimethylated copolyester while the shrinkage factor of the polyester film in the hot-water of 80 deg.C is 30% or more in either one of lengthwise or widthwise direction, further, next formula is satisfied between the fusing seal strength and heat shrinkage stress; 10<=alpha/beta<=50. In the formula, alpha means the fusing seal strength (g/15mm) of the film of thickness 12mmu and beta means the heat shrinkage stress (kg/cm<2>) in the hot-water of 80 deg.C.

Inventors

• 👤 Yutaka Watanabe
• 👤 豊 渡辺
• 👤 Mitsuhiko Saito
• 👤 光彦 斉藤
• 👤 Suminori Tanaka
• 👤 住典 田中

Bibliographic Details