Fluorine-containing organopolysiloxane, a surface treatment composition comprising the same and an article treated with the composition

1. A fluorine-containing organopolysiloxane represented by the following average compositional formula (1)

(Z 2 Q) β Rf(QZ 1 A α ) 2−β   (1)

wherein Rf is a divalent group containing a perfluoroether residue,

Q is a divalent organic group,

Z 1 is a di- to nona-valent organopolysiloxane residue and may contain a silalkylene bond,

α is an integer of from 1 to 8,

β is a number larger than 0 and smaller than 2,

Z 2 is a monovalent group represented by the following formula (2)

wherein b is an integer of from 1 to 10, R 1 may be the same with and different from each other and is an alkyl group having 1 to 4 carbon atoms or a phenyl group, and

A is a monovalent group represented by the following formula (3)

wherein R 2 is an alkyl group having 1 to 4 carbon atoms or a phenyl group, X is a hydrolyzable group, a is 2 or 3, and c is an integer of from 1 to 6.

2. The fluorine-containing organopolysiloxane according to claim 1 , wherein Z 2 is a group represented by the following formula:

wherein Me is a methyl group.

3. The fluorine-containing organopolysiloxane according to claim 1 , wherein Z 1 is a linear or cyclic organopolysiloxane residue having 2 to 8 silicon atoms.

4. The fluorine-containing organopolysiloxane according to claim 1 , wherein Z 1 is a linear organopolysiloxane residue having 6 to 13 silicon atoms and 1 or 2 silethylene bonds.

5. The fluorine-containing organopolysiloxane according to claim 1 , wherein the perfluoroether residue contains 1 to 500 repeating units represented by the following general formula:

—C g F 2g O—

wherein g is independently an integer of from 1 to 6.

6. The fluorine-containing organopolysiloxane according to claim 1 , wherein Rf is selected from the groups represented by the following general formulas (5), (6), and (7):

wherein Y may be the same with or different from each other and is a fluorine atom or a CF 3 group, r is an integer of from 2 to 6, d is an integer of from 1 to 3, each of m and n is an integer of from 0 to 200 with m+n ranging from 2 to 200, s is an integer of from 0 to 6, and the repeating units may be bonded randomly;

—C d F 2d (CF 2 CF 2 CF 2 O) l C d F 2d —  (6)

wherein l is an integer of from 1 to 200 and d is an integer of from 1 to 3; and

wherein Y is a fluorine atom or a CF 3 group, d is an integer of from 1 to 3, each of m and n is an integer of from 0 to 200 with m+n ranging from 2 to 200, and the repeating units may be bonded randomly.

7. The fluorine-containing organopolysiloxane according to claim 1 , wherein Rf is represented by the following general formula (4):

—CF 2 (OC 2 F 4 ) e (OCF 2 ) f OCF 2 —  (4)

wherein e is an integer of from 0 to 50, f is an integer of from 1 to 50 with e+f raging from 2 to 60.

8. The fluorine-containing organopolysiloxane according to claim 1 , wherein Q is a hydrocarbon group having 3 to 12 carbon atoms and may contain at least one bond selected from the group consisting of an amide bond, an ether bond, an ester bond and a vinyl bond.

9. The fluorine-containing organopolysiloxane according to claim 1 , wherein X is selected from the group consisting of alkoxy groups, oxyalkoxy groups, acyloxy groups, alkenyloxy groups, and halogen atoms.

10. The fluorine-containing organopolysiloxane according to claim 9 , wherein X is selected from the group consisting of methoxy group, ethoxy group, isopropenoxy group and chlorine atom.

11. A surface treatment composition comprising, as an active ingredient, the fluorine-containing organopolysiloxane according to any one of claims 1 to 10 and/or a partial condensate of hydrolyzates thereof.

12. An article treated with the surface treatment composition according to claim 11 .