| 摘要 |
PROBLEM TO BE SOLVED: To provide a cement dispersing agent which is capable of improving the workability while maintaining the good finish in the manufacturing of a centrifugal molded product such as a Hume cement pipe and of shortening the compaction time. SOLUTION: The cement dispersing agent comprises the joint use of the first copolymer and the second copolymer each containing the constituent units of a specific monomer (a) such as an ethylenically unsaturated carboxylic acid derivative having a polyoxyalkylene group or the like and of a specific monomer (b) such as (meth)acrylic acid or the like, under such a condition that the difference between a mole % of (b) relative of the sum total of (a) plus (b) in the first copolymer and a mole % of (b) relative to the sum total of (a) plus (b) in the second copolymer is 5 or more. COPYRIGHT: (C)2004,JPO |
