Fluorine-containing ether compound, lubricant for magnetic recording medium and magnetic recording medium
A fluorine-containing ether compound represented by a formula (1) shown below. R 4 —CH 2 —R 3 —CH 2 —R 2 —CH 2 —R 1 —CH 2 —R 2 —CH 2 —R 3 —CH 2 —R 5 (1) In formula (1), R 1 and R 3 represent the same or different perfluoropolyether chains, R 2 represents a linking group containing at least one polar group, one or both of R 4 and R 5 represent a terminal group containing two or more polar groups, and R 4 and R 5 are different.
1. A fluorine-containing ether compound represented by a formula (1) shown below:
R 4 —CH 2 —R 3 —CH 2 —R 2 —CH 2 —R 1 —CH 2 —R 2 —CH 2 —R 3 —CH 2 —R 5 (1)
wherein R 1 and R 3 represent identical or different perfluoropolyether chains, R 2 represents a linking group containing at least one polar group, one or both of R 4 and R 5 represent a terminal group containing two or more polar groups, R 4 and R 5 are different, and R 4 and R 5 are each a hydroxyl group or one terminal group selected from among formulas (2-1) to (2-5) shown below:
wherein r represents an integer of 0 to 4,
wherein p represents an integer of 1 to 5,
wherein s represents an integer of 2 to 5,
wherein t represents an integer of 1 to 5,
wherein q represents an integer of 2 to 5.
2. The fluorine-containing ether compound according to claim 1 , wherein one or both of R 1 and R 3 in the formula (1) are represented by a formula (3) shown below:
wherein m represents an integer of 1 to 20, and n represents an integer of 0 to 10.
3. The fluorine-containing ether compound according to claim 1 , wherein R 3 in the formula (1) is represented by a formula (4) shown below or a formula (5) shown below:
wherein u represents an integer of 1 to 30,
wherein v represents an integer of 1 to 30.
4. The fluorine-containing ether compound according to claim 1 , wherein a number of carbon atoms in R 2 in the formula (1) is from 1 to 20.
5. The fluorine-containing ether compound according to claim 1 , wherein R 2 in the formula (1) is represented by a formula (6) shown below:
wherein w represents an integer of 1 to 4.
6. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (D) shown below, and Rf 1 in the formula (D) is represented by a formula (RF-1) shown below:
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
7. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (G) shown below, and Rf 1 in the formula (G) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
8. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (H) shown below, and Rf 1 in the formula (H) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
9. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (J) shown below, and Rf 1 in the formula (J) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
10. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (K) shown below, and Rf 1 in the formula (K) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
11. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (L) shown below, and Rf 1 in the formula (L) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
12. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (O) shown below, and Rf 2 in the formula (O) is represented by a formula (RF-2) shown below:
wherein z represents an integer of 1 to 9.
13. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (Q) shown below, and Rf 2 in the formula (Q) is represented by a formula (RF-2):
wherein z represents an integer of 1 to 9.
14. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (R) shown below, and Rf 2 in the formula (R) is represented by a formula (RF-2):
wherein z represents an integer of 1 to 9.
15. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (U) shown below, and Rf 1 in the formula (U) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
16. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (X) shown below, and Rf 1 in the formula (X) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
17. The fluorine-containing ether compound according to claim 1 , wherein the compound represented by the formula (1) is represented by a formula (Z) shown below, and Rf 1 in the formula (Z) is represented by a formula (RF-1):
wherein x represents an integer of 1 to 7, and y represents an integer of 1 to 7.
18. The fluorine-containing ether compound according to claim 1 , having a number average molecular weight within a range from 1,000 to 10,000.
19. A lubricant for a magnetic recording medium comprising the fluorine-containing ether compound according to claim 1 .
20. A magnetic recording medium comprising at least a magnetic layer, a protective layer and a lubricant layer provided sequentially on a substrate, wherein the lubricant layer contains the fluorine-containing ether compound according to claim 1 .
21. The magnetic recording medium according to claim 20 , wherein an average thickness of the lubricant layer is from 0.5 nm to 3 nm.
22. A fluorine-containing ether compound represented by a formula (1) shown below:
R 4 —CH 2 —R 3 —CH 2 —R 2 —CH 2 —R 1 —CH 2 —R 2 —CH 2 —R 3 —CH 2 —R 5 (1)
wherein R 1 and R 3 represent identical or different perfluoropolyether chains, R 2 represents a linking group containing at least one polar group, one of R 4 and R 5 represents a terminal group containing two or more polar groups, and the other of R 4 and R 5 is a hydroxyl group.
23. A lubricant for a magnetic recording medium comprising the fluorine-containing ether compound according to claim 22 .
24. A magnetic recording medium comprising at least a magnetic layer, a protective layer and a lubricant layer provided sequentially on a substrate, wherein the lubricant layer contains the fluorine-containing ether compound according to claim 22 .