US 6,716,386 B2 · Plastic bottle and method of producing the same

Abstract

A bottle having substantially no strain due to fluidized orientation in the bottom portion thereof which is homogeneously and uniformly drawn, and, as a result, exhibiting improved shock resistance and buckling strength in the bottom portion, featuring excellent resistance against environmental cracking at the center in the bottom portion, without developing crazing or whitening during the preservation, and offering excellent appearance. The bottle is formed by biaxially stretch-blow-molding a thermoplastic resin, and has a mouth portion, a shoulder portion, a barrel portion and a bottom portion, said bottom portion without being substantially affected by the residual strain due to orientation by fluidization.

Claims7

Dependent claims

A method of producing a bottle having a support ring in an outer periphery of a mouth portion thereof by biaxially stretch-blow-molding a pre-molded article for blow molding having the support ring and a barrel portion with bottom, wherein

said pre-molded article is obtainable through the steps of:
extruding a molten thermoplastic resin and cutting it into a mass of melt of nearly a predetermined amount;
arranging a male metal mold and a female metal mold so as to move relative to each other and feeding the mass of melt into the metal mold;
compression-molding the mass of melt into a pre-molded article while forming an and an annular groove in an inner peripheral edge in the lower surface of the support ring so that a change in the mass of the molten resin from the predetermined amount is absorbed as a change in height of the annular groove;
and
cooling and solidifying the compression-molded article and discharging the molded article out of the metal mold.

3 more elements

Dependencies are inferred from the claim text.

Plastic bottle and method of producing the same

Life of this patent

Plastic bottle and method of producing the same

Life of this patent

Abstract

Claims7