Abstract: A method of making a plastic container having a body and a finish with at least one external thread includes injection or compression molding a plastic preform having a body and a finish with at least one external thread, blow molding the body of the preform to form the body of the container, and either prior to, subsequent to or both prior and subsequent to blow molding the container body, expanding the injection or compression molded preform finish to form a container finish having at least one injection or compression molded external thread. In the preferred embodiments of the invention, the finish is expanded after the container body is blow-molded. The invention can be implemented to expand a narrow-neck preform or container finish to a wide-mouth preform or container finish.

Abstract: A method of making a plastic container having a threaded wide-mouth finish includes providing a preform having at least an exterior surface of molded polyester construction. The preform is placed in a mold cavity having a first portion for forming a container body, a second portion adjacent to the first portion for forming a cylindrical finish wall without threads, and a third portion adjacent to the second portion for forming a trim dome or moil. The preform is expanded within the mold cavity to form a one-piece intermediate product that includes a body, a cylindrical wide-mouth finish wall and a moil. After removing the intermediate product from the cavity, the moil is severed from the end of the finish wall. At least one thread is then formed on the finish wall by engaging the finish wall with at least one thread-forming tool, which may be heated to facilitate the forming operation.

Abstract: A container, a container preform and a method of making the container or preform in which the finish of the preform or container is at least partially of crystallizable polymer construction, and has an end portion remote from the body of the preform or container, a capping flange adjacent to the body of the preform or container, and a mid portion between the end portion and the capping flange. The end portion of the finish forms an end surface, and the end and mid portions of the finish form continuous inner and outer surfaces. The polymer material in at least one of the end, inner and outer surfaces is crystallized, and crystallization in the finish in a direction perpendicular to such surface is graded from crystallization at the surface to an essential absence of crystallization at a position within the finish spaced from the surface.