Patent ID: 6569376
Filing Date: 2003-05-27
Classification: B29C,B29L,B65D

Abstract:
A blow-molding process for improving material thickness distribution within a bottle base portion having a noncircular cross-sectional shape generally perpendicular to a longitudinal axis of said bottle, said process comprising:positioning a heated preform in a mold-cavity having a mold-base region with at least one upstanding rib; expanding said preform with air pressure against said upstanding rib and causing said preform to traverse a longer surface distance across said upstanding rib than would be traversed had said upstanding rib not been present; positioning a closed-end of said preform in close proximity to said mold-base region before said preform completely expands, wherein said expanding of said preform against said upstanding rib includes the step of causing material flowing from said closed-end of said preform to be at least partially directed along said upstanding rib; expanding said preform against a remainder of said mold-base region and said mold-cavity to form said bottle; and removing said bottle from said mold-cavity.