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:
May. 08, 1990
Filed:
May. 01, 1989
James L Gibb, Woodbury, MN (US);
James A Laird, St. Joseph, WI (US);
Leslie G Berntson, Minneapolis, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
Ceramic particulates useful as a proppant in hydraulic fracturing and in gravel packing operations is provided which comprises a ceramic (sometimes vitreous) core surrounded by an epoxy resin coating. Novolac epoxy resin compounds without any substantial acid soluble filler are used to coat ceramic particulates similar to those discloses in U.S. Pat. Nos. 4,680,230 and 4,632,876. The result is a product which combines the excellent solvent resistance of the ceramics with the acid resistance of the resin. The resin coating gives the added benefits of lower specific gravity and improved crush resistance.