Curable composition

A curable composition comprising:

• a fluorine-containing silane 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;
• an organosilicon compound having at least two —O—Rg3(s) each bonding to a Si atom, wherein each Rg3 is as defined below;
• and
• a metal-based catalyst,
• wherein the metal-based catalyst is at least one selected from the group consisting of tetrapropyl titanate and tetrapropyl zirconate;
• the fluorine-containing silane compound is at least one perfluoropolyether group-containing silane compound represented by formula (A), (B), (C) or (D):
• wherein:
• each PFPE, at each occurrence, is independently a group represented by formula:
• —(OC6F12)a—(OC5F10)b—(OC4F8)c—(OC3F6)d—(OC2F4)e—(OCF2)f—
• wherein a, b, c, d, e and f are each independently an integer of 0 or more and 200 or less, the sum of a, b, c, d, e and f is at least 1, the occurrence order of the respective repeating units in parentheses with a, b, c, d, e or f is not limited in the formula, and each X10, at each occurrence, is independently a hydrogen atom, a fluorine atom or a chlorine atom;
• each R13, at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;
• each R14, at each occurrence, independently represents a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;
• each R11, at each occurrence, independently represents a hydrogen atom or a halogen atom;
• each R12, at each occurrence, independently represents a hydrogen atom or a lower alkyl group;
• R11″, R12″, R13″ and R14″ have the same meanings as R11, R12, R13 and R14, respectively;
• n1 with respect to each (—SiR13n1R143−n1) unit or each (—SiR13″n1R14″3−n1) unit is independently an integer of 0 to 3;
• provided that at least two groups selected from the group consisting of R13 and R13″, at each occurrence, are each independently present in formulae (A) and (B);
• each X1, at each occurrence, independently represents a single bond or a di- to decavalent organic group;
• each X2, 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 X3, 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 X5, 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 Ra, at each occurrence, independently represents —Z3—SiR71p1R72q1R73r1;
• each Z3, at each occurrence, independently represents an oxygen atom or a divalent organic group;
• each R71, at each occurrence, independently represents Ra′;
• Ra′ has the same meaning as Ra;
• the number of Si linearly linked via a Z3 group in Ra is at most 5;
• each R72, at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;
• each R73, 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 Ra″, at each occurrence, independently represents —Z3—SiR71p1R72″q1R73r1;
• R72″ has the same meaning as R72;
• provided that the sum of p1, q1 and r1 with respect to (—Z3—SiR71p1R72q1R73r1) or with respect to (—Z3—SiR71p1R72″q1R73r1) is 3 and at least one q1 in formula (C) is an integer of 1 to 3;
• each Rb, at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;
• each Rc, at each occurrence, independently represents a hydrogen atom or a lower alkyl group;
• Rb″ and Rc″ have the same meanings as Rb and Rc, 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 (SiRak1Rbl1Rcm1) or with respect to (SiRa″k1Rb″l1Rc″m1) is 3;
• at least two groups selected from the group consisting of Rb, Rb″, R72 and R72″ are present in (C);
• each X7 independently represents a single bond or a di- to decavalent organic group;
• each δ1 is independently an integer of 1 to 9;
• each Rd, at each occurrence, independently represents —Z4—CR81p2R82 q2R83 r2,
• each Z4, at each occurrence, independently represents an oxygen atom or a divalent organic group;
• each R81, at each occurrence, independently represents Rd′;
• Rd′ has the same meaning as Rd;
• the number of C linearly bonded via a Z4 group in Rd is at most 5;
• each R82, at each occurrence, independently represents —Y—SiR85n2R863−n2;
• each Y, at each occurrence, independently represents a divalent organic group;
• each R85, at each occurrence, independently represents a hydroxyl group or a hydrolyzable group;
• each R86, at each occurrence, independently represents a hydrogen atom or a lower alkyl group;
• each R83, at each occurrence, independently represents a hydrogen atom, a hydroxyl group 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 Rd″, at each occurrence, independently represents —Z4—CR81p2R82″q2R83r2;
• R82″ represents —Y—SiR85″n2R86″3−n2,
• provided that the sum of p2, q2 and r2 with respect to (—Z4—CR81p2R82q2R83r2) or with respect to (—Z4—CR81p2R82″q2R83r2) is 3,
• n2 with respect to a (—Y—SiR85n2R863−n2) unit or with respect to a (—Y—SiR85″n2R86″3−n2) unit independently represents an integer of 0 to 3;
• R85″ and R86″ have the same meanings as R85 and R86, respectively;
• each Re, at each occurrence, independently represents —Y—SiR85n2R863−n2;
• each Re″, at each occurrence, independently represents —Y—SiR85″n2R86″3−n2;
• each Rf, at each occurrence, independently represents a hydrogen atom, a hydroxyl group or a lower alkyl group;
• Rf″ has the same meaning as Rf;
• 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 (CRdk2Rel2Rfm2) or with respect to (CRd″k2Re″l2Rf″m2) is 3, and two or more groups selected from the group consisting of a group represented by —Y—SiR85n2R863−n2 wherein n2 is 1 or more and a group represented by —Y—SiR85″n2R86″3−n2 wherein n2 is 1 or more are present in formula (D);
• the organosilicon compound comprises any organosilicon compound represented by the following formulae (E1) to (E5):
• or the organosilicon compound selected from the group consisting of tetraethoxysilane, tetramethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, tridecafluoro-n-octyltriethoxysilane, and tridecafluoro-n-octyltrimethoxysilane;
• wherein:
• each Rg1, at each occurrence, is independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms;
• each Rg2, at each occurrence, is independently substituted or unsubstituted and has 1 to 20 carbon atoms;
• each Rg3, at each occurrence, is independently a hydrogen atom or a monovalent organic group;
• each Rg4, at each occurrence, is independently a monovalent organic group;
• Rg6 represents Rg8-Rg7-;
• each Rg7, at each occurrence, independently represents a single bond, an oxygen atom or a divalent organic group;
• each Rg8, 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 an integer of 0 or more;
• ε6 is 1 or 2;
• and
• provided that the sum of ε4, ε5 and ε6 is 4.