| 摘要 |
PROBLEM TO BE SOLVED: To provide a muddy water which does largely not change the thixotropic property, even when contaminated with an impure substance such as a salt, and has an excellent property for conveying dug earth and sand. SOLUTION: This mud-adding agent comprises a copolymer prepared by polymerizing a monomer component consisting essentially of (A) a monomer having a carboxy group and/or its salt group and (B) a monomer having a group represented by general formula (1) äR<SP>1</SP>is one or more groups selected from methylene group, ethylene group, propylene group and butylene group; (n) is 10 to 300 [n (R<SP>1</SP>-O) groups may be only one kind or more kinds]; X is C(=O) or C(=O)NH; (m) is 0 or 1; R<SP>2</SP>is a 6 to 30C hydrocarbon group}. COPYRIGHT: (C)2005,JPO&NCIPI |
