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:
Aug. 02, 1999
Filed:
Dec. 06, 1993
Applicant:
Inventors:
Robert Barnett Rhodes, Houston, TX (US);
Harvey E Atwood, Kingwood, TX (US);
John Eugene Gorman, Houston, TX (US);
Assignee:
Shell Oil Company, Houston, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C09K / ;
U.S. Cl.
CPC ...
525314 ;
Abstract
The present invention includes star polymers which can be used as viscosity index improvers in oil compositions formulated for high performance engines. The star polymers have copolymer arms of hydrogenated polyisoprene and polystyrene with sufficient amounts of polystyrene to be finishable as a polymer crumb.