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. 17, 2019
Filed:
Dec. 28, 2015
Applicant:
Kureha Corporation, Tokyo, JP;
Inventors:
Takeo Takahashi, Tokyo, JP;
Masayuki Okura, Tokyo, JP;
Assignee:
KUREHA CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 33/12 (2006.01); C08G 18/32 (2006.01); C08L 33/08 (2006.01); E21B 43/16 (2006.01); C08L 33/20 (2006.01); C08L 75/04 (2006.01); C08L 101/00 (2006.01);
U.S. Cl.
CPC ...
C08G 18/3221 (2013.01); C08L 33/08 (2013.01); C08L 33/20 (2013.01); C08L 75/04 (2013.01); C08L 101/00 (2013.01); E21B 33/12 (2013.01); E21B 43/16 (2013.01);
Abstract
Provided is a rubber member for downhole tools, of which a decrease rate of 50% strain compressive stress after immersion for 24 hours in 150° C. water relative to 50% strain compressive stress before immersion is not less than 5%, and preferably not less than 50%. The rubber member is suitable for a seal member, ball sealer, ball seat, and a protecting member. Also provided is a downhole tool comprising the rubber member, and a method for recovering a hydrocarbon resource using the downhole tool.