US 6,645,634 B1Granted

Magnetic recording medium and method for manufacturing same

AssigneeFuji Electric Co., Ltd.

InventorsShinji Shirai, Youichi Tei

Life of this patent

Estimating the term…

Loading patent…

Abstract

To avoid troubles associated with high-density recording and fast transfer rate, such as decomposition of lubricant involved in a low floating height magnetic head and migration of lubricants involved in high speed rotation of a magnetic recording medium, and to provide a magnetic recording medium which achieves stable resistance to environment and stable lubricating characteristics, a magnetic recording medium includes a base body and the layers formed on the base body, including a non-magnetic metal underlayer, a magnetic layer, a protective layer, and a lubricant layer. The lubricant of the lubricant layer includes a perfluoropolyether liquid lubricant having an alcohol end group(s) and a perfluoropolyether liquid lubricant having an amine end group(s) of tertiary amine structure.

Claims18

Dependent claims

A magnetic recording medium comprising:

a base body;
a non-magnetic metal underlayer formed on the base body;
a magnetic layer formed on the non-magnetic metal layer;
a protective layer formed on the magnetic layer;
and
a lubricant layer formed on the protective layer, the lubricant layer containing a first liquid lubricant and a second liquid lubricant, wherein the first liquid lubricant contains at least one perfluoropolyether having one or two alcohol end groups, selected from a group consisting of perfluoropolyethers represented by general formulas (I), (II) and (III), the general formulas (I), (II) and (III) being expressed by
HOCH2—(CF2CF2O)l-(CF2O)m—CH2OH (I)
F(CF2CF2CF2O)n—CH2OH (II)
F(CF2CF2O)n—CH2OH (III)
where each of l and m is 0 or an integer excepting the case l=m=0, and n is an integer, and
the second liquid lubricant contains at least one perfluoropolyether having one or two tertiary amine end groups, selected from a group consisting of perfluoropolyethers represented by general formulas (IV), (V) and (VI), the general formulas (IV), (V) and (VI) being expressed by
RN—(CH2)p—(CF2CF2O)l—(CF2O)m—(CH2)q—NR (IV)
F(CF2CF2CF2O)n—(CH2)p—NR (V)
F(CF2CF2O)n—(CH2)p—NR (VI)
where R is independently Chemical Formula 3, Chemical Formula 4, or Chemical Formula 5,
and each of l, m, p and q is 0 or an integer excepting the case l=m=0, and n is an integer.

13 more elements

A method for manufacturing a magnetic recording medium comprising steps of:

laminating a non-magnetic metal underlayer on a base body;
laminating a magnetic layer on the non-magnetic metal underlayer;
laminating a protective layer on the magnetic layer;
and
laminating a lubricant layer on the protective layer by applying a first liquid lubricant and a second liquid lubricant;
wherein the first liquid lubricant contains at least one perfluoropolyether having one or two alcohol end groups, selected from a group consisting of perfluoropolyethers represented by general formulas (I), (II) and (III), the general formulas (I), (II) and (III) being expressed by
HOCH2—(CF2CF2O)l-(CF2O)m—CH2OH (I)
F(CF2CF2CF2O)n—CH2OH (II)
F(CF2CF2O)n—CH2OH (III)
where each of l and m is 0 or an integer excepting the case l=m=0, and n is an integer, and
the second liquid lubricant contains at least one perfluoropolyether having one or two tertiary amine end groups, selected from a group consisting of perfluoropolyethers represented by general formulas (IV), (V) ad (VI), the general formulas (IV), (V) and (VI) being expressed by
RN—(CH2)p—(CF2CF2O)l—(CF2O)m—(CH2)q—NR (IV)
F(CF2CF2CF2O)n—(CH2)p—NR (V)
F(CF2CF2O)n—(CH2)p—NR (VI)
where R is independently Chemical Formula 3, Chemical Formula 4, or Chemical Formula 5,
and each of l, m, p and q is 0 or an integer excepting the case l=m=0, and n is an integer.

13 more elements

Dependencies are inferred from the claim text.