DRY SHRINKAGE REDUCER FOR PREMIXED MORTAR, PREMIXED MORTAR AND CEMENT HARDENED BODY

摘要

PROBLEM TO BE SOLVED: To provide a dry shrinkage reducer for premixed mortar exhibiting an effect for inhibiting high dry shrinkage even when a unit volume mass is small, and inhibiting the dry shrinkage for long term.SOLUTION: There is provided a dry shrinkage reducer for premixed mortar consisting of a cationic surfactant represented by the formula (1): (NRRRR)X(1), where Ris C12 to 18 alkyl group with composition ratio of the alkyl group having 14 carbon atoms or composition ratio of the alkyl group having 16 carbon atoms in the alkyl group of 95 mass% or more, Rand Rare each independently H or a methyl group, Ris H or a benzyl group, and X is a counter ion.SELECTED DRAWING: None