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. 01, 1993
Filed:
Sep. 05, 1990
David G Bland, Knoxville, TN (US);
Joseph J Conte, Newark, OH (US);
Susan K Moeller, Newark, OH (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
A method for preparing composite foam articles by the coextrusion of at least two interdigitated layers in abutting relationship to each other, wherein at least one layer of composite article comprises at least one expanded thermoplastic resinous material. At least one physical expansion agent is incorporated into at least one of the layers under a pressure sufficient to keep the expansion agent quiescent and the individual melt streams are combined and interdigitated into a composite layered stream. The composite layered stream is expressed while the operating pressures and temperatures of individual melt streams are controlled to provide a coextrusion product having a stable foam structure.