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. 10, 2011
Filed:
Oct. 15, 2004
Peter Marten Van Der Horst, Arnhem, NL;
Peter Marten Van Der Horst, Arnhem, NL;
Abstract
The invention relates to a water-based drilling fluid composition comprising a carboxymethyl cellulose (CMC), wherein the CMC is characterized by forming a gel at 25° C. after high-shear dissolution in a 0.3 wt % aqueous sodium chloride solution, the final content of the CMC in the aqueous sodium chloride solution being I wt % for a CMC having a degree of polymerization of >4,000, 1.5. wt % for a CMC having a DP of >3,000-4,000, 2 wt % for a CMC having a DD of 1,500-3,000, and 4 wt % for a CMC having a DP of <1,500, the gel being a fluid having a storage modulus (G') which exceeds the loss modulus (G″) over the entire frequency region of 0.01-10 Hz when measured on an oscillatory rheometer operating at a strain of 0.2.