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:
Sep. 04, 1984
Filed:
Sep. 13, 1982
Compagnie Francaise de Raffinage, Paris, FR;
Abstract
A continuous process for making rigid PVC foam objects by extruding a preform from an initial PVC mixture, optionally cutting the preform into blanks, and expanding the preform or the blanks in water heated to a temperature above 70.degree. C. The initial mixture contains polyvinyl chloride, at least a first blowing agent capable of generating a gas, for example an isocyanate or a polyisocyanate, and at least one organic anhydride (and does not contain any added inert particles finely divided therein). The initial mixture may also contain less than one weight percent of a second blowing agent, for example azobisisobutyronitrile or azodicarbonamide. The objects produced possess heat- and sound-insulating properties.