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:
Apr. 07, 1981
Filed:
May. 17, 1979
Hiroyuki Akiyama, Hiratsuka, JP;
Nobuyoshi Shimoyashiki, Isehara, JP;
Hideo Hatakeyama, Hiratsuka, JP;
Toru Yamamoto, Kanuma, JP;
Japan Styrene Paper Corporation, Tokyo, JP;
Abstract
A foamed polystyrene board useful as a thermal insulating material is produced by melting a polystyrene having a melt index of from 0.5 to 5 under heat in an extruder, mixing the molten mass with a blowing agent composed of methyl chloride and dichlorodifluoromethane, and extruding the resulting foamable molten gel from the extruder. As a novel essential feature, a flowability improver having a melting point higher than 70.degree. C., such as an aromatic sulfonamide, a brominated aromatic compound, a brominated alicyclic compound or a poly(.alpha.-methylstyrene), is mixed with the polystyrene within the extruder to impart superior extrusion formability. The foam has good dimensional stability both at room temperature and higher temperature, high mechanical strength and superior thermal insulation properties.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile