US 12,338,410 B2
Lubricating agent solution, magnetic disk and method for manufacturing same
Tsuyoshi Shimizu, Kobe (JP)
Assigned to Moresco Corporation, Kobe (JP)
Appl. No. 17/632,474
Filed by Moresco Corporation, Kobe (JP)
PCT Filed May 28, 2020, PCT No. PCT/JP2020/021229
§ 371(c)(1), (2) Date Feb. 2, 2022,
PCT Pub. No. WO2021/024585, PCT Pub. Date Feb. 11, 2021.
Claims priority of application No. 2019-144650 (JP), filed on Aug. 6, 2019.
Prior Publication US 2022/0275305 A1, Sep. 1, 2022
Int. Cl. C10M 173/02 (2006.01); C10M 107/38 (2006.01); G11B 5/725 (2006.01); C10N 40/18 (2006.01)
CPC C10M 173/02 (2013.01) [C10M 107/38 (2013.01); G11B 5/7257 (2020.08); C10M 2213/0606 (2013.01); C10N 2040/18 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A lubricant solution comprising: a perfluoropolyether compound dissolved in water, wherein the perfluoropolyether compound satisfies Expression (I) below:
NOH/(Mn/1500)≥2  (I),
where NOH represents the number of hydroxyl groups contained per molecule of the perfluoropolyether compound and Mn represents a number average molecular weight of the perfluoropolyether compound; and
wherein the perfluoropolyether compound has a structure represented by Formula (2) below:
R1—R2—R3  (2)
R1 is —F, —CH2OH, —CH2OCH2CH(OH)CH2OCH2CH(OH)CH2OH, —CH2O(CH2)gOH, —CH2OCH2CH(OH)CH2OC12H9O, —CH2OCH2CH(OH)CH2OC10H7, or CH2OCH2CH(OH)CH2OC6H4—R4;
R3 is —F, —CH2OH, —CH2—O—CH2—CH(OH)CH2—OH, —CH2OCH2CH(OH)CH2OCH2CH(OH)CH2OH, —CH2O(CH2)gOH, —CH2OCH2CH(OH)CH2OC12H9O, —CH2OCH2CH(OH)CH2OC10H7, or CH2OCH2CH(OH)CH2OC6H4—R4;
g is a real number of 1 to 10;
R4 is a hydrogen atom, a hydroxyl group, an alkoxy group including one to four carbon atoms, an amino group, or an amide residue; and
R2 is a perfluoropolyether skeleton structure represented by Formula (1) below:
—(CF2)x(CF(CF3))yO(CF2O)z(CF2CF2O)l(CF2CF2CF2O)m(CF2CF2CF2CF2O)n(CF(CF3)CF2O)o—(CF(CF3))y(CF2)x—  (1),
where x is a real number of 0 to 3, y is a real number of 0 to 1, and 1, m, n, and o are each a real number of 0 to 15 such that either x or y is a real number of not less than 1 and at least any one of m, n, and o is a real number of not less than 1.