Biaxially stretched plastic bottle

Abstract

Abstract PURPOSE:To obtain a plastic bottle with a neck having a heat resistance and impact resistance by forming the neck of a plastic bottle made of polyester with an outer surface layer crystallized at a high level and an inner surface layer crystallized at a low level. CONSTITUTION:In a plastic bottle comprising the bottom 2, the body 1, the shoulder 3 and the neck 4 which is produced by a biaxially stretching blow molding of a parison of polyester, the neck 4 is made up of an outer surface layer 9 crystallized at a high level with the density above 1.36g/cc and an inner surface layer 10 crystallized at a low level with the density below 1.35g/cc. To achieve this, a heat treating means with a temperature gradient or a cooling speed gradient is employed between the outer surface layer (the outer periphery) 9 and the inner surface layer (the inner periphery) 10 of the neck 4. To be more specific, a heat treatment is performed in such a manner that the outer periphery 9 of the neck 4 is retained at 140-210 deg.C for 30sec while the inner periphery 10 thereof and other parts at a lower temperature or the temperature range shifts to the low temperature side within 20sec.

Inventors

• 👤 Shunsaku Hirata
• 👤 平田　俊策
• 👤 Kohei Shimojima
• 👤 下嶋　好平

Bibliographic Details