SURFACE TREATMENT AGENT

1 . A surface-treating agent comprising:

(α) a compound represented by the following formula (α1) or formula (α2):

wherein:

R 1 is a monovalent organic group containing a polyether chain;

R 1′ is a divalent organic group containing a polyether chain;

the polyether chain is a chain represented by formula:

—(OC 6 F 12 ) m11 —(OC 5 F 10 ) m12 —(OC 4 F 8 ) m13 —(OC 3 X 10 6 ) m14 (OC 2 F 4 ) m15 —(OCF 2 ) m16 —

wherein m11, m12, m13, m14, m15 and m1 6 are each independently 0 or an integer of 1 or more;

X 10 is independently H, F or Cl; and

the occurrence order of the respective repeating units is not limited;

X 1 is independently a silane-containing reactive crosslinkable group; and

X 2 independently represents a monovalent group; and

(β) a perfluoropolyether group-containing silane compound having an OCF 2 unit represented by the following formula (A1), (A2), (B1), (B2), (C1), (C2), (D1), (D2), or (E1):

wherein

Rf is each independently an alkyl group having 1 to 16 carbon atoms optionally substituted with one or more fluorine atoms;

PFPE is a group represented by:

—(OC 6 F 12 ) a1 —(OC 5 F 10 ) b1 —(OC 4 F 8 ) c1 —(OC 3 F 6 ) d1 —(OC 2 F 4 ) e1 —(OCF 2 ) f1 —

wherein a1, b1, c1, d1 and e1 are each independently an integer of 0 or more and 200 or less, f1 is an integer of 1 or more and 200 or less, and the occurrence order of the respective repeating units in parenthesis with a1, b1, c1, d1, e1 or f1, is not limited in the formula;

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

R 15 , at each occurrence, is each independently a hydroxyl group or a hydrolyzable group;

R 13 , at each occurrence, is each independently a hydrogen atom or a halogen atom;

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

n with respect to each (—SiR 14 n R 15 3-n ) unit is independently an integer of 0 to 3;

provided that at least one R 15 is present in formulae (A1), (A2), (B1), and (B2);

X 101 is each independently a single bond or a di- to decavalent organic group;

X 102 , at each occurrence, is each independently a single bond or a divalent organic group;

t is each independently an integer of 1 to 10;

α is each independently an integer of 1 to 9;

α′ is an integer of 1 to 9;

X 105 is each independently a single bond or a di- to decavalent organic group;

β is each independently an integer of 1 to 9;

β′ is an integer of 1 to 9;

X 107 is each independently a single bond or a di- to decavalent organic group;

γ is each independently an integer of 1 to 9;

γ′ is an integer of 1 to 9;

R a3 , at each occurrence, is each independently —Z 3 —SiR 71 p R 72 q R 73 r ;

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

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

R α′ has the same meaning as R a3 ;

the number of Si atoms linearly linked via a Z 3 group in R a3 is at most 5;

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

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

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

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

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

provided that the sum of p, q and r with respect to (—Z 3 —SiR 71 p R 72 q R 73 r ) is 3 and at least one R 72 is present in formulae (C1) and (C2);

R b3 , at each occurrence, is each independently a hydroxyl group or a hydrolyzable group;

R c3 , at each occurrence, is each independently a hydrogen atom or a lower alkyl group;

k, at each occurrence, is each independently an integer of 1 to 3;

l, at each occurrence, is each independently an integer of 0 to 2;

m, at each occurrence, is each independently an integer of 0 to 2;

provided that, in the unit in parentheses with γ, the sum of k, l and m is 3;

X 109 is each independently a single bond or a di- to decavalent organic group;

δ is each independently an integer of 1 to 9;

δ′ is an integer of 1 to 9;

R d3 , at each occurrence, is each independently —Z 3′ —CR 81 p′ R 82 q′ R 83 r′ ;

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

R 81 , at each occurrence, is each independently R d3″ ;

R d3″ has the same meaning as R d3 ;

the number of C atoms linearly linked via a Z 3′ group in R d3 is at most 5;

R 82 is —Y 3 —SiR 85 j R 86 3-j ;

Y 3 , at each occurrence, is independently a divalent organic group;

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

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

j with respect to each (—Y 3 —SiR 85 j R 86 3-j ) unit is independently an integer of 1 to 3;

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

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

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

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

R e3 , at each occurrence, is each independently —Y 3 —SiR 85 j R 86 3-j ;

R f3 , at each occurrence, is each independently a hydrogen atom, a hydroxyl group or a lower alkyl group;

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

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

m′, at each occurrence, is each independently an integer of 0 to 3,

provided that, in the formula, at least one q′ is 2 or 3 or at least one l′ is 2 or 3;

G 5 is —R 17 —O—, —R 17 —CONH—, —CONH—, or a single bond;

R 17 is an alkylene group;

Z 5 is an (a5+b5)-valent hydrocarbon group or an (a5+b5)-valent group having 2 or more carbon atoms and having at least one etheric oxygen atom between carbon atoms in the hydrocarbon group;

R 16 is an alkylene group;

a5 is an integer of 1 or more;

b5 is an integer of 1 or more;

provided that (a5+b5) is 3 or more; and

c5 is 0 or 1,

wherein the perfluoropolyether group-containing silane compound having an OCF 2 unit is a compound different from the compound represented by the following formula (α1) or formula (α2).

2 . The surface-treating agent according to claim 1 , wherein R 1 is a group represented by:

R 3 —(OR 2 ) a -L-

wherein (OR 2 ) a is a polyether chain;

R 3 is an alkyl group or a fluorinated alkyl group; and

L is a single bond or a divalent linking group; and

R 1′ is a group represented by:

-L′-(OR 2 ) a -L-

wherein (OR 2 ) a is a polyether chain;

L is independently a single bond or a divalent linking group; and

L′ is independently a single bond or a divalent linking group.

3 . The surface-treating agent according to claim 2 , wherein (OR 2 ) a is a group represented by:

—(OC 4 F 8 ) m13 —(OC 3 F 6 ) m14 —(OC 2 F 4 ) m15 —(OCF 2 ) m16 —

wherein m13 and m14 are each an integer of 0 to 30, and m15 and m16 are each an integer of 1 to 200; m13 to m16 are 5 or more in total; and the occurrence order of the respective repeating units is not limited.

4 . The surface-treating agent according to claim 2 , wherein L is a group represented by:

—(CX 121 X 122 ) o -(L 1 ) p -(CX 123 X 124 ) q —

wherein X 121 to X 124 are each independently H, F, OH, or —OSi(OR 125 ) 3 wherein three R 125 are each independently an alkyl group having 1 to 4 carbon atoms;

L 1 is —C(═O)NH—, —NHC(═O)—, —O—, —C(═O)O—, —OC(═O)—, —OC(═O)O—, or —NHC(═O)NH—, in which the left side of each bond is bonded to CX 121 X 122 ;

o is an integer of 0 to 10;

p is 0 or 1; and

q is an integer of 1 to 10; and

L′ is a group represented by:

—(CX 126 X 127 ) r —(CX 121 X 122 ) o -(L 1 ) p -(CX 123 X 124 ) q —

wherein X 121 to X 124 , L 1 , o, p, and q have the same meanings as defined in L;

X 126 and X 127 are each independently H, F or Cl; and

r is an integer of 1 to 6.

5 . The surface-treating agent according to claim 1 , wherein X 1 is a group represented by the formula:

-L 2 -{Si(R a ) s (R b ) t (R c ) u (R d ) v } n

wherein L 2 is a single bond or a divalent linking group;

R a , R b and R c are the same or different and are each hydrogen, halogen, an alkoxy group having 1 to 10 carbon atoms, an amino group having 1 to 10 carbon atoms, an acetoxy group having 1 to 10 carbon atoms, an allyl group having 3 to 10 carbon atoms, or a glycidyl group having 3 to 10 carbon atoms;

R d is the same or different and is —O—, —NH—, —C≡C—, or a silane bond;

s, t and u are the same or different and are each 0 or 1;

v is an integer of 0 to 3;

n is an integer of 1 to 20;

in a case where n is 1, s+t+u is 3 and v is 0;

in a case where n is 2 to 20, s+t+u is the same or different and is 0 to 2, and v is the same or different and is 0 to 2; and

in a case where v is an integer of 1 or more, at least two Si atoms are bonded to each other via R d in a linear, ladder, cyclic, or polycyclic form.

6 . The surface-treating agent according to claim 1 , wherein X 1 is a group represented by -L 2 -SiR 5 3 , -L 2 -Si(OR 6 ) 3 , -L 2 -Si(NR 6 2 ) 3 or -L 2 -Si(OCOR 6 ) 3

wherein L 2 is —C 2 H 4 —, —C 3 H 6 —, —C 4 H 8 —O—CH 2 —, —CO—O—CH 2 —CH(OH)—CH 2 —, —CH 2 —, or —C 4 H 8 —;

R 5 is a halogen atom; and

R 6 is independently an alkyl group having 1 to 4 carbon atoms.

7 . The surface-treating agent according to claim 1 , wherein X 1 is a silane-containing reactive crosslinkable group represented by the formula:

-L 2 -{Si(R a ) s (R b ) t (R c ) u (R d′ ) v } n

wherein L 2 is a single bond or a divalent linking group;

R a , R b and R c are the same or different and are each hydrogen, halogen, an alkoxy group having 1 to 10 carbon atoms, an amino group having 1 to 10 carbon atoms, an acetoxy group having 1 to 10 carbon atoms, an allyl group having 3 to 10 carbon atoms, or a glycidyl group having 3 to 10 carbon atoms;

R d′ are the same or different, and is a group represented by —Z—SiR d1′ p′ R d2′ q′ R d3′ r′

wherein Z is the same or different and is a single bond or a divalent linking group;

R d1′ is the same or different and is R d″ ;

R d″ has the same meaning as R d′ ;

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

R d2′ is the same or different and is a hydroxyl group or a hydrolyzable group;

R d3′ is the same or different and is a hydrogen atom or a lower alkyl group;

p′ is the same or different and is an integer of 0 to 3;

q′ is the same or different and is an integer of 0 to 3; and

r′ is the same or different and is an integer of 0 to 3;

provided that the sum of p′, q′ and r′ is 3;

s, t and u are the same or different and are each 0 or 1;

v is an integer of 0 to 3; and

n is an integer of 1 to 20.

8 . The surface-treating agent according to claim 1 , wherein X 1 is a silane-containing reactive crosslinkable group represented by the formula:

-L 6 -{C(R a6 ) s6 (R b6 ) t6 (R c6 ) u6 (R d6 ) v6 } n6

wherein L 6 is a single bond or a divalent linking group;

R a6 , R b6 and R c6 are the same or different and are each hydrogen, halogen, an alkoxy group having 1 to 10 carbon atoms, an amino group having 1 to 10 carbon atoms, an acetoxy group having 1 to 10 carbon atoms, an allyl group having 3 to 10 carbon atoms, a glycidyl group having 3 to 10 carbon atoms, OCOR 67 , wherein R 67 is an alkyl group having 1 to 6 carbon atoms, OH or —Y 6 —SiR 65 j6 R 66 3-j6 ;

R d6 is the same or different and is —O—, —NH—, —C≡C—, or —Z 6 —CR 61 p6 R 62 q6 R 63 r6 ;

Z 6 is the same or different and is an oxygen atom or a divalent organic group;

wherein R 61 is the same or different and represents R d6′ ;

R d6′ has the same meaning as R d6 ;

the number of C atoms linearly linked via a Z 6 group in R d6 is at most 5;

R 62 is the same or different and is —Y 6 —SiR 65 j6 R 66 3-j6 ;

Y 6 is the same or different and is a divalent organic group;

R 65 is the same or different and is a hydroxyl group or a hydrolyzable group;

R 66 is the same or different and is a hydrogen atom or a lower alkyl group;

j6 with respect to each (—Y 6 —SiR 65 j6 R 66 3-j6 ) unit is independently an integer of 1 to 3;

R 63 is the same or different and is a hydrogen atom or a lower alkyl group;

p6 is the same or different and is an integer of 0 to 3;

q6 is the same or different and is an integer of 0 to 3;

r6 is the same or different and is an integer of 0 to 3; and

s6, t6 and u6 are the same or different and are each 0 or 1, v6 is an integer of 0 to 3, and n6 is an integer of 1 to 20,

provided that in the formula, at least two —Y 6 —SiR 65 j6 R 66 3-j6 are present.

9 . The surface-treating agent according to claim 1 , wherein (β) the perfluoropolyether group-containing silane compound having an OCF 2 unit is a compound represented by formula (C1) or (C2).

10 . The surface-treating agent according to claim 1 , wherein PFPE is a group represented by:

—(OC 4 F 8 ) m13 —(OC 3 F6) m14 —(OC 2 F 4 ) m15 —(OCF 2 ) m16 —

wherein m13 and m14 are each an integer of 0 to 30, and m15 and m16 are each an integer of 1 to 200; and the occurrence order of the respective repeating units is not limited.

11 . The surface-treating agent according to claim 1 , further comprising a solvent.

12 . The surface-treating agent according to claim 1 , for use as an antifouling coating agent or a water-proof coating agent.

13 . The surface-treating agent according to claim 1 , which is for vacuum deposition.

14 . A pellet comprising the surface-treating agent according to claim 1 .

15 . An article comprising: a base material; and a layer formed on a surface of the base material from the surface-treating agent according to claim 1 .

16 . The article according to claim 15 , wherein the article is an optical member.