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:
Jan. 17, 1995
Filed:
Sep. 15, 1992
Mark H Kayser, Woodbury, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
Long-term algicidal granules show improved color fastness over previously known granules. The granules have a ceramic coating comprising three layers, the first two of which have a copper compound such as cuprous oxide therein at relatively equal amounts. The ceramic coating further includes a third layer having pigment, a borate compound, and zinc oxide having an average particle size less than about 0.13 micrometer. In particular it has been found that the use of cuprous oxide allows conversion to black cupric oxide, which is more insoluble than cuprous oxide and black in color, allowing the algae-resistant granules to retain their original color for loger periods of time under weathering conditions. Methods of producing such ceramic-coated granular materials are also disclosed.