Copolymer for cosmetics, surface treatment agent for cosmetic powder, powder for cosmetics, and cosmetic preparation

A copolymer, comprising:

• 70 to 90 wt % of a constituent unit (A) derived from a compound represented by formula (a) shown below;
• 2 to 25 wt % of a constituent unit (B) derived from a compound represented by formula (b) shown below;
• 2 to 25 wt % of a constituent unit (C) derived from a compound represented by formula (c) shown below;
• 0.1 to 10 wt % of a constituent unit (D) derived from a compound represented by formula (d) shown below;
• and
• a residue (E) of an OH group- or COOH group-comprising chain transfer agent (e),
• CH2═CR1—COO-Q1-Rf (a)
• where
• Q1 is a single bond or a divalent linking group;
• R1 is a hydrogen atom or a methyl group;
• and
• Rf is a polyfluoroalkyl group comprising 1 to 6 carbon atoms or a polyfluoroether group,
• CH2═CR2-Q2-COOH (b)
• where
• Q2 is a single bond or a divalent linking group;
• and
• R2 is a hydrogen atom, a methyl group or a COOH group,
• CH2═CR3—COO—(R4O)n-R5 (c)
• where
• R3 is a hydrogen atom or a methyl group;
• each R4 is independently an alkylene group comprising 2 to 4 carbon atoms in which a part or all of hydrogen atoms is optionally substituted with OH groups;
• n is a number of from 1 to 300;
• R5 is a hydrogen atom, an alkyl group comprising 1 to 4 carbon atoms or a group represented by formula (s):
• —CO—CR6═CH2 (s), where R6 is a hydrogen atom or a methyl group,
• CH2═CR7—COO-Q3-P(O)(OH)—R8 (d)
• where
• Q3 is a single bond or a divalent linking group;
• R7 is a hydrogen atom or a methyl group;
• R8 is an OH group or a group represented by formula (t):
• -Q4-OCO—CR9═CH2 (t), where
• Q4 is a single bond or a divalent linking group;
• and
• R9 is a hydrogen atom or a methyl group.