초록 ▼

This relates to a returnable/refillable container in the form of a blow molded polyester biaxially oriented bottle wherein the container includes a domed base construction wherein the wall thickness gradually and smoothly increases to a maximum at the center of the dome. This also relates to a speci

This relates to a returnable/refillable container in the form of a blow molded polyester biaxially oriented bottle wherein the container includes a domed base construction wherein the wall thickness gradually and smoothly increases to a maximum at the center of the dome. This also relates to a specially configurated preform which is blow molded to form the container and a specially configurated blow mold cavity for receiving a preform having a lower axial projection in the fore of an elongated gate without crushing.

대표청구항 ▼

[ We claim:] [1.] A preform for use in blow molding a container suitable for refilling, the preform being an injection molded polyester member having:a closed bottom end and an open top end;a neck finish at the open top end;a body-forming portion which on blow molding will form a body of the contain

[ We claim:] [1.] A preform for use in blow molding a container suitable for refilling, the preform being an injection molded polyester member having:a closed bottom end and an open top end;a neck finish at the open top end;a body-forming portion which on blow molding will form a body of the container;a shoulder-forming portion disposed between the neck finish and the body-forming portion and which on blow molding will form a shoulder of the container; anda base-forming portion which on blow molding will form a base of the container, the base-forming portion having a generally hemispherical outer surface at the closed bottom end and a thickened portion between the bottom end and the body forming portion, the thickened portion having an increased wall thickness as compared to the wall thickness of the body-forming portion;characterized in that the base-forming portion has a generally hemispherical inner surface at the bottom end and the thickened portiom has an upper cylindrical portion of the increased wall thickness and a lower tapered portion which gradually reduces in wall thickness towards the bottom end.