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. 16, 2002
Filed:
Nov. 06, 1997
Applicant:
Inventors:
Hans-Peter Kohlstadt, Velbert, DE;
Klaus Marten, Dormagen, DE;
Lothar Thiele, Leichlingen, DE;
Werner Fahle, Cottbus, DE;
Rainer Tost, Cottbus, DE;
Annebärbel Tost, Cottbus, DE;
Peter Tost, Cottbus, DE;
Frank Tost, Cottbus, DE;
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D 2/700 ;
U.S. Cl.
CPC ...
B01D 2/700 ;
Abstract
The invention relates to a filter in which dust-containing silica sand is held together by a polyurethane binder, the polyurethane binder containing an organotin compound with a molecular weight of more than 600 as catalyst and a mixture of highly dispersed silica and/or bentonites with a thickened aluminosilicate as modifier. The filter is particularly suitable for the production of drinking water from ground water in surface mining regions.