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. 15, 1992
Filed:
Apr. 23, 1991
David A Huddleston, Sugar Land, TX (US);
Robert K Gabel, Houston, TX (US);
Charles D Williamson, Sugar Land, TX (US);
Nalco Chemical Company, Naperville, IL (US);
Abstract
A process for forming an oil well cement composition comprising: mixing cement and a vinyl grafted wattle tannin fluid loss additive, the vinyl grafted wattle tannin comprising a wattle tannin grafted with at least one vinyl monomer selected from the group consisting of: 2-acrylamido-2-methylpropanesulfonic acid and acrylamide, wherein the wattle tannin is present in an amount of between about 0.05 to about 14 weight percent based on actives, the 2-acrylamido-2-methylpropanesulfonic acid is present in an amount of between about 68 to about 99.95 percent, and acrylamide is present in an amount of between about 0 to about 18 percent, to form a cement blend; and mixing the cement blend with water.