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. 03, 1991
Filed:
Jul. 06, 1990
Applicant:
Inventors:
Isidoor De Grave, Wachenheim, DE;
Udo Haardt, Biblis, DE;
Wolfram Koegel, Mannheim, DE;
Fritz E Krueckau, Battenberg, DE;
Hermann Tatzel, Weinheim, DE;
Assignee:
BASF Aktiengesellschaft, Ludwigshafen, DE;
Primary Examiner:
Int. Cl.
CPC ...
B29C / ;
U.S. Cl.
CPC ...
264 53 ; 264321 ; 521 58 ; 521142 ; 521143 ; 521918 ;
Abstract
Foam particles of propylene polymers which have shrunk from 40 to 95% of their original volume and have a bulk density of from 10 to 30 g/1 can be expanded if they are treated with air or nitrogen under superatmospheric pressure, subsequently decompressed. If desired post-foamed by heating and, after aging, re-treated with air or nitrogen under superatmospheric pressure, subsequently decompressed and aged under atmospheric pressure until the pressure in the cells has dissipated.