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:
Aug. 23, 1988
Filed:
Jun. 22, 1987
Applicant:
Inventors:
Assignee:
Tonen Sekiyukagaku K.K., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08J / ;
U.S. Cl.
CPC ...
521134 ; 264D / ; 264 54 ; 521140 ; 521143 ; 521144 ; 521915 ; 521 515 ;
Abstract
The invention relates to the process of the invention provides a radiation-crosslinked polypropylene foam by extrusion at a low temperature (about 170.degree. C.) below the decomposition point of the blowing agent. The resulting foamed item has by far better heat resistance than conventional ones. The raw resin can be prepared by mixing a resin in the pellet form and a blowing agent in the powder form on account of the low-temperature flowability. Heretofore, such mixing was impossible because the blowing agent does not disperse completely. This outstanding effect of the invention was not expected at all from the known prior arts.