Lubricant for magnetic recording media, and magnetic recording medium

Patent metadata

Field	Value
Publication number	US-2018362874-A1
Application number	US-201615780171-A
Country	US
Kind code	A1
Filing date	Dec 6, 2016
Priority date	Dec 7, 2015
Publication date	Dec 20, 2018
Grant date	—

Abstract

Provided is a lubricant for magnetic recording medium, where the lubricant includes an ionic liquid including an anionic component and a cationic component, wherein the anionic component includes a fluorine-containing chain having a number average molecular weight of 1,500 or less, the cationic component is a cation of cyclic amidine, and the cation of the cyclic amidine includes a fluorine-containing chain that is either a perfluoroalkyl chain or a perfluoropolyether chain.

First claim

1 . A lubricant for magnetic recording media comprising:
an ionic liquid including an anionic component and a cationic component,
wherein the anionic component includes a fluorine-containing chain having a number average molecular weight of 1,500 or less,
the cationic component is a cation of cyclic amidine, and
the cation of the cyclic amidine includes a fluorine-containing chain that is either a perfluoroalkyl chain or a perfluoropolyether chain.

2 . The lubricant for magnetic recording media according to claim 1 ,
wherein the ionic liquid is represented by General Formula (1) below,

where, in General Formula (1), Rf is a perfluoropolyether chain having, as a repeating unit, a perfluoroalkyloxy chain having from 1 to 4 carbon atoms,
X is an alkylene group having 2 or more carbon atoms, an oxyalkylene group having 1 or more carbon atoms and 1 or more repeating units, or any combination thereof,
Y is a single bond or a divalent linking group,
R is a hydrogen atom or a hydrocarbon group having from 1 to 22 carbon atoms, and
Z − is the anionic component.

3 . The lubricant for magnetic recording media according to claim 1 ,
wherein the anionic component is a sulfonic acid anion including the fluorine-containing chain, a sulfonyl imide anion including the fluorine-containing chain, or sulfonyl methide anion including the fluorine-containing chain.

4 . The lubricant for magnetic recording media according to claim 2 ,
wherein, in General Formula (I), the number of atoms in a straight chain connecting *1 and *2 of a divalent group represented by a structural formula below is 2 or greater,
* 1 —Y—X—* 2 .

5 . A magnetic recording medium comprising:
a non-magnetic support; a magnetic layer disposed on the non-magnetic support; and the lubricant for magnetic recording media according to claim 1 , where the lubricant is disposed on the magnetic layer.

Assignees

• Dexerials Corp

Inventors

• Tano Nobuo
• Hatsuda Kouki
• Kondo Hirofumi

Classifications

• C10N2030/08

  Resistance to extreme temperature · CPC title

• C10N2020/077

  Ionic Liquids · CPC title

• C10M2213/06

  Perfluoro polymers · CPC title

• C10M2215/221

  Six-membered rings containing nitrogen and carbon only · CPC title

• C10M2219/044

  Sulfonic acids, Derivatives thereof, e.g. neutral salts · CPC title