(10) US 2012/0125236 A1
(22) Dec. 8, 2008
(43) May 24, 2012
(76) Raita Iwata, Chigasaki (JP); Tomomi Sugiyama, Chigasaki (JP); Takumi Sugamata, Chigasaki (JP)
(57) To provide shrinkage reducing agents which render excellent shrinkage reducing effect and frost-thaw resistance to cement compositions such as mortar and concrete without entraining excessive air, and exhibit excellent solution stability. The shrinkage reducing agent comprises a (poly)alkylene compound having an unsaturated bond represented by the formula (1):
R2O–R1–O-(A1O)n–R3(1)
-(A2O)m–R4(2)
(wherein R1 is a C2-10 hydrocarbon group...