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:
Jun. 29, 1976
Filed:
Jan. 22, 1975
Keith G Johnson, Pittsburgh, PA (US);
ARCO Polymers, Inc., Philadelphia, PA (US);
Abstract
Thermoplastic polymers containing a blowing agent are extruded into an unconfined zone and allowed to partially expand. The polymers are then conveyed through a confined moving passage of predetermined configuration formed, for example, by intermeshing cooled rolls, to shape the extrudate to the predetermined configuration and solidify the surface layers. The extrudate is further cooled by subjecting alternate surfaces to cooled roll surfaces, whereby a continuous ribbon, or shaped extrudate, having a dense skin and a foamed core is formed. The method is particularly applicable to small cross-section profiles which can be cut into short lengths to be useful as ice-cream sticks or tongue depressors.