| abstract |
A kind of surface-treated powder of offer is provided, i.e. by being hydrophobicity time dry, when contacting with water, becomes hydrophilic, thus make up retentivity and washability deposit.Specifically, the surface-treated powder that the 1st block copolymer represented by following formula (1) by powder surface is covered, In formula (1), R 1 、R 2 Representing alkyl, polyoxyalkylene, acyl group, phenyl, aralkyl independently of one another, the carbon atom that X cannot not represent adjacently can be replaced by oxygen atom thus form the alkyl chain of the carbon number 1～18 of ether, and Y represents the linking group of singly-bound or divalent, Z 1 Representing hydrogen atom or methyl, n, m represent the degree of polymerization. |