Fluorine-containing ether compound, lubricant for magnetic recording medium, and magnetic recording medium

Abstract

Provided is a fluorine-containing ether compound that can form a lubricating layer that is resistant to chemicals even if the thickness is thin, and that can be used as a material for a lubricant for a magnetic recording medium. The fluorine-containing ether compound is represented by the following formula. R 1 -CH2-R 2 -CH2-OCH2-CHR 3 -CH2O-CH2-R 4 -CH2-R 5 (In the formula, R 2 and R 4 are perfluoropolyether chains. R 1 and R 5 are terminal groups in which two or three hydroxyl groups are each bonded to a different carbon atom, and the carbon atoms to which the hydroxyl groups are bonded are each bonded to each other via a linking group that includes a carbon atom to which no hydroxyl group is bonded. R 3 are represented by the following formula. -(CH2) a -OH (a is an integer from 2 to 8).

Claims

1. A fluorinated ether compound, characterized in that, It is represented by the following formula (1), R 1 -CH2-R 2 -CH2-OCH2-CHR 3 -CH2O-CH2-R 4 -CH2-R 5 (1) In equation (1), R 2 and R 4 It is a perfluoropolyether chain, R 2 With R 4 The same, and represented by any one of the following formulas (5) to (7) and (9); -CF2O-(CF2O) w5 -(CF2CF2O) x5 -CF2- (5) In equation (5), w5 and x5 represent the average degree of polymerization, each representing a real number from 1 to 20 independently; -CF2O-(CF2CF2O) x6 -CF2- (6) In equation (6), x6 represents the average degree of polymerization, which is a real number from 1 to 20; -CF2CF2O-(CF2CF2CF2O) y7 -CF2CF2- (7) In equation (7), y7 represents the average degree of polymerization, which is a real number from 1 to 20; -CF2CF2CF2O-(CF2CF2CF2CF2O) z9 -CF2CF2CF2- (9) In equation (9), z9 represents the average degree of polymerization, which is a real number from 1 to 20; In equation (1), R 1 and R 5 R is a terminal group containing two or three hydroxyl groups, each hydroxyl group being bonded to a different carbon atom, and the carbon atoms bonded to the hydroxyl groups being bonded to each other via a linker containing a carbon atom of an unbonded hydroxyl group. 1 With R 5 The same, and is any one of the following formulas (3-1) to (3-5); In equation (3-1), i is an integer from 0 to 1, and j is an integer from 1 to 4; In equation (3-2), k is an integer from 1 to 2, and l is an integer from 1 to 3; In equation (3-3), m is an integer from 1 to 3; In equation (3-4), n is an integer from 1 to 2; In equation (1), R 3 It is represented by the following formula (2), -(CH2) a -OH (2) In equation (2), a represents an integer from 2 to 8.

2. The fluorinated ether compound according to claim 1, wherein a in formula (2) is an integer from 3 to 6.

3. The fluorinated ether compound according to claim 1 or 2, wherein the number average molecular weight is in the range of 500 to 10,000.

4. A lubricant for magnetic recording media, characterized in that, The compound comprising any one of claims 1 to 3.

5. A magnetic recording medium, characterized in that, It is a magnetic recording medium on which at least a magnetic layer, a protective layer, and a lubricating layer are sequentially disposed on a substrate. The lubricating layer comprises any one of the fluorinated ether compounds according to claims 1 to 3.

6. The magnetic recording medium according to claim 5, wherein the average film thickness of the lubricating layer is 0.5 nm to 2.0 nm.

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