Curable surface modifier and curable composition for surface modification prepared from same

A curable surface modifier comprising a curable fluorine-containing resin (I) which is soluble in general purpose solvents and has a fluorine content of not less than 0.1% by weight and not more than 35% by weight,

• said curable fluorine-containing resin (I) comprises a fluorine-containing ethylenic polymer (IAB) having a moiety A and a moiety B in at least a part of the same side chain or different side chains thereof or comprises a fluorine-containing ethylenic polymer (IA) having a moiety A in at least a part of its side chain and a fluorine-containing ethylenic polymer (IB) having a moiety B in at least a part of its side chain, in which the moiety A has, at its end, one or two or more polyfluoropolyether chains P represented by the formula (1):
• wherein n1, n2, n3 and n4 are the same or different and each is 0 or an integer of 1 or more and n1+n2+n3+n4 is an integer of not less than 10;
• X1 are the same or different and each is H, F or Cl;
• Rf is a fluorine-containing alkyl group having 1 to 10 carbon atoms,
• the moiety B has one or two or more self-crosslinkable functional groups Y at its end, and
• an ethylenic polymer moiety M remaining by excluding the moiety A and the moiety B from the fluorine-containing ethylenic polymer constituting the resin (I) does not contain fluorine atom or is an ethylenic polymer moiety in which a part of hydrogen atoms thereof are replaced by fluorine atoms up to a fluorine content of not more than 10% by weight, and the ethylenic polymer moiety M contains a structural unit of the formula (2):
• or the formula (3):
• wherein X2 is H or a bond;
• X3 is H, F or CH3.