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:
Jul. 21, 1998
Filed:
Mar. 07, 1996
Applicant:
Inventors:
Akira Yada, Shiga, JP;
Yoshihiro Kawamori, Kyoto, JP;
Hiroshi Nishiguchi, Shiga, JP;
Akira Kitada, Shiga, JP;
Yoshiyuki Mori, Shiga, JP;
Assignee:
Dai-Ichi Kogyo Seiyaku Co., Ltd., Kyoto, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08F / ;
U.S. Cl.
CPC ...
525 59 ; 524803 ; 525 57 ; 525 60 ; 525 61 ;
Abstract
A modified polyvinyl alcohol is disclosed, which comprises the following structural units (I) and (II) and has a weight average molecular weight of from 3,000 to 400,000: ##STR1## wherein R.sup.1 represents H or CH.sub.3 ; and M.sup.1 represents H, an alkali metal, ammonium, alkylammonium, or alkanolammonium. The modified polyvinyl alcohol may be sulfonated. The modified polyvinyl alcohol is used as a dispersant such as a drilling fluid additive.