Fluorinated ether compound, composition for forming hard coating layer, and article having hard coating layer

1. A fluorinated ether compound comprising:

a poly(oxyperfluoroalkylene) chain having a repeated unit that comprises an oxyperfluorodimethylene group and an oxyperfluorotetramethylene group, bonded to each other,

a linking group bonded to a first terminal of the poly(oxyperfluoroalkylene) chain, and

at least one (meth)acryloyl group bonded to the linking group.

2. The fluorinated ether compound according to claim 1 , wherein at a second terminal of the poly(oxyperfluoroalkylene) chain is bonded when the second terminal atom is a carbon atom, or a perfluoroalkyl group is bonded when the second terminal atom is an oxygen atom.

3. The fluorinated ether compound according to claim 2 , wherein the second terminal of the poly(oxyperfluoroalkylene) chain is at a side where a C 2 oxyperfluoroalkylene group is present.

4. The fluorinated ether compound according to claim 1 , which has a number average molecular weight of from 2,000 to 40,000.

5. A fluorinated ether compound represented by the following formula (1):

A-O—[R f1 O—R f2 O] n —B  (1),

wherein:

n is an integer of at least 2,

R f1 is a perfluorodimethylene group,

R f2 is a perfluorotetramethylene,

A is a C 1-6 perfluoroalkyl group, a C 2-6 perfluoroalkyl group having an etheric oxygen atom, or B,

B is a group represented by the following formula (2):

—R f3 (CX 2 ) m1 —Y 1 -Q-[Y 2 C(═O)C(R)═CH 2 ] m2   (2),

wherein:

R f3 is a C 1-20 perfluoroalkylene group which optionally has an etheric oxygen atom between carbon atoms,

X is a hydrogen atom or a fluorine atom,

m1 is 0 or 1,

Y 1 is a single bond, —C(═O)NH—, wherein Q is bonded to N, —OC(═O)NH—, wherein Q is bonded to N, —O—, —C(═O)O—, wherein Q is bonded to O, —OC(═O)O—, —NHC(═O)NH— or —NHC(═O)O—, wherein Q is bonded to O,

Q is a single bond or a m2+1 valent organic group,

Y 2 is —O—, —NH— or —NHC(═O)O—(C k H 2k )—O—, wherein k is an integer of from 1 to 10, and Q is bonded to N,

R is a hydrogen atom or a methyl group,

m2 is an integer of at least 1,

wherein, when m1 is 0, Y 1 is not —O—, —OC(═O)NH— or —OC(═O)—, when Y 1 is —C(═O)NH—, —OC(═O)NH—, —O—, —C(═O)O—, —OC(═O)O—, —NHC(═O)NH— or —NHC(═O)O—, Q is a m2+1 valent organic group, and when each of Y 1 and Y 2 is —O—, Q is not a single bond.

6. The fluorinated ether compound according to claim 5 , wherein the B is —CF 2 CF 2 OCF 2 CF 2 CF 2 CH 2 —OC(═O)C(R)═CH 2 .

7. The fluorinated ether compound according to claim 5 , wherein the B is —CF 2 CF 2 OCF 2 CF 2 CF 2 CH 2 —O—C(═O)NH-Q-[NHC(═O)O—(C k H 2k )—O—C(═O)C(R)═CH 2 ] m2 , wherein m2 is 1 or 2, provided that when m2 is 1, Q is a bivalent group obtained by removing two isocyanate groups from a diisocyante compound, and when m2 is 2, Q is a trivalent group obtained by removing three isocyanate groups from a triisocyanate compound, and k is an integer of from 2 to 6.

8. A composition for forming a hard coating layer, comprising the fluorinated ether compound of claim 1 , a photopolymerizable compound that does not comprise the fluorinated ether compound, and a photopolymerization initiator.

9. The composition for forming a hard coating layer according to claim 8 , wherein a content of the fluorinated ether compound is from 0.01 to 5 mass %, based on 100 mass % of a solid content.

10. The composition for forming a hard coating layer according to claim 8 , further comprising a medium.

11. A composition for forming a hard coating layer, comprising the fluorinated ether compound of claim 5 , a photopolymerizable compound that does not comprise the fluorinated ether compound, and a photopolymerization initiator.

12. The composition for forming a hard coating layer according to claim 11 , wherein a content of the fluorinated ether compound is from 0.01 to 5 mass %, based on 100 mass % of a solid content.

13. The composition for forming a hard coating layer according to claim 11 , further comprising a medium.

14. An article comprising a substrate and a hard coating layer formed from the composition of claim 8 .

15. The article according to claim 14 , wherein the substrate comprises a metal, a resin, glass, ceramics or a composite material thereof.

16. An article comprising a substrate and a hard coating layer formed from the composition of claim 11 .

17. The article according to claim 16 , wherein the substrate comprises a metal, a resin, glass, ceramics or a composite material thereof.