The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 20, 1983
Filed:
Jun. 08, 1981
Claude Bonnebat, Pontault Combault, FR;
Louis Macabrey, Mitry-le-Neuf, FR;
Rhone-Poulenc Industries, Paris, FR;
Abstract
An elongate, rigid, tubular, biaxially oriented thermoplastic, hollow thin-walled shaped article is molded by (i) introducing into an elongate mold cavity, the internal configuration and dimensions thereof corresponding to the exterior surface area of the desired shaped article, and aligning along the longitudinal axis thereof, a hollow tubular thermoplastic preform heated to the biaxial orientation temperature of said thermoplastic; (ii) expanding under internal pressure said heated preform to simultaneously, both longitudinally and transversely, uniformly stretch same, at least to the natural biaxial drawing ratio thereof, but to a value in the transverse direction of less than 100% of that ultimately desired; (iii) next further expanding said heated preform, under increased internal pressure, completely against the internal walls of the mold cavity to thus completely shape said ultimately desired shaped article; and (iv) then cooling said desired shaped article and releasing all pressure therefrom.