Patent ID: 8604103

Claim:
An additive composition for a hydraulic composition, comprising: (A) one or more copolymers selected from the group consisting of compounds (1), (2) and (3) shown below; and (B) a mixture of compounds represented by the general formula (B2) shown below <compound (1)> a copolymer, or a salt thereof, of an alkenyl ether derivative represented by the general formula (A1) and a monomer represented by the general formula (A3): R 1a (A 2 O) n1 R 2a (A1) wherein R 1a represents an alkenyl group having 2 to 4 carbon atoms, A 2 O represents an oxyalkylene group having 2 to 3 carbon atoms, n1 is a number of 2 to 200 that is the average number of moles of A 2 O added, and R 2a represents an alkyl group having 1 to 3 carbon atoms; wherein R 5a to R 7a independently represent a hydrogen atom, a methyl group or (CH 2 ) p2 COOM 2 , M 1 and M 2 independently represent a hydrogen atom or a cation, and p2 represents a number of 0 to 2; <compound (2)> a copolymer comprising, as constituent units, a monomer (i) represented by the general formula (A2) shown below and one or more monomers (ii) selected from the group consisting of compounds represented by the general formulae (A3) above shown and the general formula (A4) shown below, having a molar ratio of (ii)/(i)=70/30 to 95/5; wherein R 3a and R 4a independently represent a hydrogen atom or a methyl group, p1 represents a number of 0 to 2, A 3 O represents an oxyalkylene group having 2 to 3 carbon atoms, n2 is a number of 100 to 300 that is the average number of moles of A 3 O added, and X represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; wherein R 8a represents a hydrogen atom or a methyl group, and Y represents a hydrogen atom or a cation; <compound (3)> a copolymer comprising, as constituent units, a monomer unit (iii) represented by the general formula (A5) shown below and one or more monomers (ii) selected from the group consisting of compounds represented by the general formulae (A3) and (A4) above shown, having a molar ratio of (ii)/(iii)=60/40 to 90/10; wherein R 9a and R 10a independently represent a hydrogen atom or a methyl group, p3 represents a number of 0 to 2, A 4 O represents an oxyalkylene group having 2 to 3 carbon atoms, n3 is a number of 2 to 90 that is the average number of moles of A 4 O added, and X represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; wherein A 1 represents an alkylene group having 2 to 4 carbon atoms, m1, m2 and m3 each represent an integer indicating the number of moles of A 1 O added, and wherein the average of the sum in total of m1, m2 and m3 of the mixture of compounds represented by the general formula (B2) is 0.5 to 2.5.