| abstract |
Disclosed is a surface treatment agent improved in terms of solubility in a solvent and wear resistance of a cured film. The present invention includes at least one perfluoropolyether block and at least one polyorganosiloxane block that may contain a silalkylene group, each having one group represented by the following formula (1) at both ends. And a perfluoropolyether-polyorganosiloxane copolymer having a number average molecular weight (polystyrene conversion) of 7000 to 25000. (X is a hydrolyzable group, R 1 is an alkyl group having 1 to 4 carbon atoms or a phenyl group, y is an integer of 1 to 5, and a is 2 or 3.) [Selection figure] None |