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:
Jan. 23, 2007
Filed:
Jan. 03, 2003
Gary A. Francis, Canandaigua, NY (US);
Wen P. Wu, Pittsford, NY (US);
Gary A. Francis, Canandaigua, NY (US);
Wen P. Wu, Pittsford, NY (US);
Pactiv Corporation, Lake Forest, IL (US);
Abstract
A method for producing an alkenyl aromatic polymer foam structure that comprises melting at least one alkenyl aromatic polymer resin. An effective amount of blowing agent mixture is dissolved in the at least one alkenyl aromatic polymer. The blowing agent mixture comprises at least one VOC blowing agent and acetone. The majority by mole percent of the VOC blowing agent is selected from n-butane, iso-butane, propane and combinations thereof. An extrudate is formed comprising the at least one alkenyl aromatic polymer resin, the at least one VOC blowing agent, and acetone. The extrudate comprises less than about 2.7 wt. % of the at least one VOC blowing agent. The extrudate is transferred to an expansion zone and permitted to expand to produce the foam structure. The foam structure has an extruded density less than about 7 lbs/ftand a basis weight of less than about 20 grams per 100 in.