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. 11, 1978
Filed:
Mar. 05, 1975
Applicant:
Inventors:
Hermann Schindler, Fischbach, Taunus, DT;
Wolfgang Zimmermann, Frankfurt am Main, DT;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DT;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29D / ;
U.S. Cl.
CPC ...
264 49 ; 260 / ;
Abstract
Starch products which were hitherto used as pore-forming substances in the manufacture of polyvinyl alcohol acetal sponges are replaced by polyethylene glycol or polyacrylamide. This results in a more uniform distribution of pore size, lower shrinkage of the sponge material during the acetalization, and easier washing of the sponge after the acetalization.