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. 07, 1993
Filed:
Jul. 20, 1992
Katsuya Matsumoto, Ishioka, JP;
Nobuyoshi Kotani, Hirakata, JP;
Naruyuki Ida, Hyogo, JP;
Yoshio Miyano, Kuze, JP;
Sanwa Kako Company Limited, , JP;
Abstract
An open-cell foam of a cross-linked polyolefin possessing uniform physical properties, a high degree of expansion, and a high open-cell ratio can be produced with high operational efficiency and high material utilization by a method which includes thermally shaping under pressure a foamable and cross-linkable polyolefin composition capable of being heated with a microwave, then heating the composition by irradiation with a microwave thereby inducing partial decomposition of a cross-linking agent and a foaming agent contained in the composition, subsequently externally heating under normal pressure the resultant intermediate partially foamed product thereby effecting decomposition of the remainders of the cross-linking agent and foaming agent, and thereafter subjecting the resultant foam to mechanical deformation thereby establishing intercommunication among the cells. The surface of the foamable and cross-linkable polyolefin composition may be heated prior to the heating with a microwave to effect partial cross-linking of the surface part of the composition.