Lubricant for magnetic recording media, and magnetic recording medium using the lubricant
View Patent ↗A magnetic recording medium having high bonding capability between the surface lubricant and the diamond-like carbon (DLC) protective layer in the surface of the magnetic recording medium is disclosed. The lubricant is a fluorine-containing lubricant for magnetic recording media represented by the following formula (1), (2) or (3), wherein the substituents R 1 , R 2 , R 3 , R 4 , R 5 and R 6 in the terminal part of the lubricant each independently represent an organic group, and at least one of the substituents R 1 and R 2 , at least one of the substituents R 3 and R 4 , and at least one of the substituents R 5 and R 6 each have an isocyanate group: Also disclosed is a magnetic recording medium using the lubricant.
1. A fluorine-containing lubricant for magnetic recording media represented by the following formula (2) or (3),
R 3 —(CF 2 CF 2 CF 2 O) r —R 4 (2)
wherein r indicates a positive integer,
wherein s indicates a positive integer,
wherein the substituents R 3 , R 4 , R 5 and R 6 in the terminal part of the lubricant each independently represent an organic group, and at least one of the substituents R 3 and R 4 , and at least one of the substituents R 5 and R 6 each is CH 2 OCONH(CH 2 ) 6 NCO.
2. The lubricant as claimed in claim 1 , wherein the R 3 or R 4 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination and wherein the R 5 or R 6 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination.
3. A magnetic recording medium having at least a magnetic layer, a protective layer and a lubricant layer on a nonmagnetic substrate, wherein the lubricant layer contains a lubricant represented by the following formula (2) or (3), and wherein the substituents R 3 , R 4 , R 5 and R 6 in the terminal part of the lubricant each independently represent an organic group, and at least one of the substituents R 3 and R 4 , and at least one of the substituents R 5 and R 6 each is CH 2 OCONH(CH 2 ) 6 NCO:
R 3 —(CF 2 CF 2 CF 2 O) r —R 4 (2)
wherein r indicates a positive integer,
wherein s indicates a positive integer.
4. The magnetic recording medium as claimed in claim 3 , wherein the R 3 or R 4 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination and wherein the R 5 or R 6 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination.
5. The lubricant as claimed in claim 1 , represented by formula (2).
6. The lubricant as claimed in claim 5 , wherein the R 3 or R 4 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination.
7. The lubricant as claimed in claim 1 , represented by formula (3).
8. The lubricant as claimed in claim 7 , wherein the R 5 or R 6 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination.
9. The magnetic recording medium as claimed in claim 3 , wherein the lubricant is represented by formula (2).
10. The magnetic recording medium as claimed in claim 9 , wherein the R 3 or R 4 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination.
11. The magnetic recording medium as claimed in claim 3 , wherein the lubricant is represented by formula (3).
12. The magnetic recording medium as claimed in claim 11 , wherein the R 5 or R 6 substituent that is not CH 2 OCONH(CH 2 ) 6 NCO has a skeleton selected from a group consisting of a saturated or unsaturated hydrocarbon, an aromatic hydrocarbon, an aromatic amine, a hetero ring, a heterocyclic amine and their combination.