Curable composition

1. A curable composition comprising:

a perfluoro(poly)ether group-containing silane compound which is a compound having two or more Si atoms each bonding to at least one group selected from the group consisting of a hydroxyl group and a hydrolyzable group, and a perfluoro(poly)ether group, wherein

the perfluoro(poly)ether group is a group represented by formula:

—(OC 6 F 12 ) a —(OC 5 F 10 ) b —(OC 4 F 8 ) c —(OC 3 X 10 6 ) d —(OC 2 F 4 ) e —(OCF 2 ) f —

wherein a, b, c and d are each independently an integer of 0 or more and 30 or less, e and f are each independently an integer of 1 or more and 200 or less, the sum of a, b, c, d, e and f is at least 5 or more, the occurrence order of the respective repeating units in parentheses with the subscript a, b, c, d, e or f is not limited in the formula, a ratio of e to f is 1.2 or more and 1.5 or less, a ratio of the sum of e and f to the sum of a, b, c, d, e and f is 0.80 or more, and each X 10 , at each occurrence, is independently a hydrogen atom, a fluorine atom or a chlorine atom;

an organosilicon compound having at least two —O—R g3 (s) each bonding to a Si atom, wherein each R g3 , at each occurrence, is independently a hydrogen atom or a monovalent organic group; and

a catalyst.

2. The curable composition according to claim 1 , wherein the perfluoro(poly)ether group-containing silane compound is at least one perfluoro(poly)ether group-containing silane compound represented by formula (A), (B), (C) or (D):

wherein:

each PFPE 1 , at each occurrence, is independently a group represented by formula:

—(OC 6 F 12 ) a —(OC 5 F 10 ) b —(OC 4 F 8 ) c —(OC 3 X 10 6 ) d —(OC 2 F 4 ) e —(OCF 2 ) f —

wherein a, b, c and d are each independently an integer of 0 or more and 30 or less, e and f are each independently an integer of 1 or more and 200 or less, the sum of a, b, c, d, e and f is at least 5 or more, the occurrence order of the respective repeating units in parentheses with the subscript a, b, c, d, e or f is not limited in the formula, a ratio of e to f is 1.2 or more and 1.5 or less, a ratio of the sum of e and f to the sum of a, b, c, d, e and f is 0.80 or more, and each X 10 , at each occurrence, is independently a hydrogen atom, a fluorine atom or a chlorine atom;

each R 13 , at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;

each R 14 , at each occurrence, independently represents a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

each R 11 , at each occurrence, independently represents a hydrogen atom or a halogen atom;

each R 12 , at each occurrence, independently represents a hydrogen atom or a lower alkyl group;

R 11″ , R 12″ , R 13″ and R 14′ have the same meanings as R 11 , R 12 , R 13 and R 14 , respectively;

n1 with respect to each (—SiR 13 n1 R 14 3-n1 ) unit or each (—SiR 13″ n1 R 14″ 3-n1 ) unit is independently an integer of 0 to 3;

provided that at least two R 13 groups, or at least two R 13″ groups, or at least one R 13 group and at least one R 13″ group, at each occurrence, are each independently present in formulae (A) and (B);

each X 1 , at each occurrence, independently represents a single bond or a di- to decavalent organic group;

each X 2 , at each occurrence, independently represents a single bond or a divalent organic group;

each t, at each occurrence, is independently an integer of 1 to 10;

each α1, at each occurrence, is independently an integer of 1 to 9;

each X 3 , at each occurrence, independently represents a single bond or a di- to decavalent organic group;

each β1, at each occurrence, is independently an integer of 1 to 9;

each X 5 , at each occurrence, independently represents a single bond or a di- to decavalent organic group;

each γ1, at each occurrence, is independently an integer of 1 to 9;

each R a , at each occurrence, independently represents —Z 3 —SiR 71 p1 R 72 q1 R 73 r1 ;

each Z 3 , at each occurrence, independently represents an oxygen atom or a divalent organic group;

each R 71 , at each occurrence, independently represents R a′ ;

R a′ has the same meanings as R a ;

the number of Si linearly linked via a Z 3 group in R a is at most 5;

each R 72 , at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;

each R 73 , at each occurrence, independently represents a hydrogen atom or a lower alkyl group;

each p1, at each occurrence, is independently an integer of 0 to 3;

each q1, at each occurrence, is independently an integer of 0 to 3;

each r1, at each occurrence, is independently an integer of 0 to 3;

each R a″ , at each occurrence, independently represents —Z 3 —SiR 71 p1 R 72″ q1 R 73 r1 ;

R 72″ has the same meanings as R 72 ;

provided that the sum of p1, q1 and r1 with respect to (—Z 3 —SiR 71 p1 R 72 q1 R 73 r1 ) or (—Z 3 —SiR 71 p1 R 72″ q1 R 73 r1 ) is 3 and at least one q1 in formula (C) is an integer of 1 to 3;

each R b , at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;

each R c , at each occurrence, independently represents a hydrogen atom or a lower alkyl group;

R b″ and R c″ have the same meanings as R b and R c , respectively;

each k1, at each occurrence, is independently an integer of 0 to 3;

each l1, at each occurrence, is independently an integer of 0 to 3;

each m1, at each occurrence, is independently an integer of 0 to 3;

provided that the sum of k1, l1 and m1 with respect to each (SiR a k1 R b l1 R c m1 ) or each (SiR a″ k1 R b″ l1 R c″ m1 ) is 3;

at least two R b groups, or at least two R b″ groups, or at least two R 72 groups, or at least two R 72″ groups, or at least two groups selected from the group consisting of R b , R b″ , R 72 and R 72″ are present in (C);

each X 7 independently represents a single bond or a di- to decavalent organic group;

each δ1 is independently an integer of 1 to 9;

each R d , at each occurrence, independently represents —Z 4 —CR 81 p2 R 82 q2 R 83 r2 ;

each Z 4 , at each occurrence, independently represents an oxygen atom or a divalent organic group;

each R 81 , at each occurrence, independently represents R d′ ;

R d′ has the same meanings as R d ;

the number of C linearly linked via a Z 4 group in R d is at most 5;

each R 82 , at each occurrence, independently represents —Y—SiR 85 n2 R 86 3-n2 ;

each Y, at each occurrence, independently represents a divalent organic group;

each R 85 , at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;

each R 86 , at each occurrence, independently represents a hydrogen atom or a lower alkyl group;

each R 83 , at each occurrence, independently represents a hydrogen atom or a lower alkyl group;

each p2, at each occurrence, is independently an integer of 0 to 3;

each q2, at each occurrence, is independently an integer of 0 to 3;

each r2, at each occurrence, is independently an integer of 0 to 3;

each R d″ , at each occurrence, independently represents —Z 4 —CR 81 p2 R 82″ q2 R 83 r2 ;

R 82″ represents —Y—SiR 85″ n2 R 86″ 3-n2 ;

provided that the sum of p2, q2 and r2 with respect to (—Z 4 —CR 81 p2 R 82 q2 R 83 r2 ) or (—Z 4 —CR 81 p2 R 82″ q2 R 83 r2 ) is 3;

n2 with respect to a (—Y—SiR 85 n2 R 86 3-n2 ) unit or a (—Y—SiR 85″ n2 R 86″ 3-n2 ) unit independently represents an integer of 0 to 3;

R 85″ and R 86″ have the same meanings as R 85 and R 86 , respectively;

each R e , at each occurrence, independently represents —Y—SiR 85 n2 R 86 3-n2 ;

each R e″ , at each occurrence, independently represents —Y—SiR 85″ n2 R 86″ 3-n2 ;

each R f , at each occurrence, independently represents a hydrogen atom, a hydroxyl group or a lower alkyl group;

R f″ has the same meanings as R f ;

each k2, at each occurrence, is independently an integer of 0 to 3;

each l2, at each occurrence, is independently an integer of 0 to 3; and

each m2, at each occurrence, is independently an integer of 0 to 3;

provided that the sum of k2, l2 and m2 with respect to (CR d k2 R e l2 R f m2 ) or (CR d″ k2 R e″ l2 R f″ m2 ) is 3, and two or more groups selected from the group consisting of a group represented by —Y—SiR 85 n2 R 86 3-n2 wherein n2 is 1 or more and a group represented by —Y—SiR 85″ n2 R 86″ 3-n2 wherein n2 is 1 or more are present in formula (D).

3. The curable composition according to claim 1 , wherein such a Si atom bonding to at least one group selected from the group consisting of a hydroxyl group and a hydrolyzable group is present at each of both ends of a molecular backbone of the perfluoro(poly)ether group-containing silane compound.

4. The curable composition according to claim 1 , wherein the catalyst is at least one selected from the group consisting of a metal-based catalyst, an organic acid-based catalyst, an inorganic acid-based catalyst and a basic catalyst.

5. The curable composition according to claim 1 , wherein the catalyst is a metal-based catalyst comprising a titanium atom, a zirconium atom or a tin atom.

6. The curable composition according to claim 1 , comprising 0.1 to 5.0 parts by mass of the catalyst based on 100 parts by mass of the perfluoro(poly)ether group-containing silane compound.

7. The curable composition according to claim 1 , wherein the organosilicon compound comprises an organosilicon compound represented by any of the following formulae (E1) to (E5):

wherein:

each R g1 , at each occurrence, is independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms;

each R g2 , at each occurrence, is independently substituted or unsubstituted and has 1 to 20 carbon atoms;

each R g3 , at each occurrence, is independently a hydrogen atom or a monovalent organic group;

each R g4 , at each occurrence, is independently a monovalent organic group;

R g6 represents R g8 —R g7 —;

each R g7 , at each occurrence, independently represents a single bond, an oxygen atom or a divalent organic group;

each R g8 , at each occurrence, is independently an amino group, an epoxy group, a methacrylic group, a vinyl group or a mercapto group;

each ε1, at each occurrence, is independently an integer of 1 or more;

each ε2, at occurrence, is independently 2 or 3;

each ε3, at each occurrence, is independently 2 or 3;

ε4 is an integer of 2 or more;

ε5 is 1 or 2; and

ε6 is an integer of 0 or more.

8. The curable composition according to claim 1 , comprising 0.1 to 30 parts by mass of the organosilicon compound based on 100 parts by mass of the perfluoro(poly)ether group-containing silane compound.

9. The curable composition according to claim 1 , wherein X 10 is a fluorine atom.