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. 18, 1978
Filed:
Sep. 29, 1975
Fumio Saito, Tsurunosato Ohtsu, JA;
Fumito Yamai, Kusatsu, JA;
Yositugu Beppu, Shiga, JA;
Shinpei Nakayama, Kusatsu, JA;
Sekisui Kagaku Kogyo Kabushiki Kaisha, Osaka, JA;
Sekisui Kaseihin Kogyo Kabushiki Kaisha, Nara, JA;
Abstract
Styrenic polymer particles having a substantially uniform particle size are prepared by suspending styrenic polymer particles having particle sizes in a certain range in water to provide an aqueous suspension and after adding to the suspension a styrenic monomer, a suspension polymerization catalyst and a polymerization retarder in an amount of 1/200 to 1/15 mole per 1 mole of the catalyst, conducting the suspension polymerization. By conducting the polymerization in the presence of a foaming agent, one can produce foamable styrenic polymer particles having a substantially uniform particle size.