JPS61104320A - Magnetic storage medium - Google Patents

Abstract

PURPOSE:To obtain a magnetic disk which obviates the attraction between a head and disk in particular and has an excellent lubricating characteristic by using a lubricating agent contg. a perfluoroalkyl phosphate compd. for coating a magnetic medium on a substrate. CONSTITUTION:Perfluoroalkyl polyether, fluorosilicone, higher fatty acid (ester, amide, etc. thereof), silicone oil, etc. are used as the lubricating agent contg. the perfluoroalkyl phosphate compd. Such lubricating agent is coated via SiO2, etc. as a protective film 3 or directly without the film 3 on the magnetic medium 2 provided on the substrate 1 such as Al alloy, anodized alumite, polyester or glass plate to form a lubricating layer 4. The layer 4 has an excellent lubricating effect and prevents the attraction of the head to the disk. Said layer is suitable for obtaining a magnetic disk device having excellent durability.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic storage body used in a magnetic storage device (such as a magnetic disk device or a magnetic drum device) and a method for manufacturing the same.

(Prior Art and its Problems) General recording/reproducing methods for a magnetic storage device including a recording/reproducing magnetic head (hereinafter referred to as a head) and a magnetic storage body include the following methods. That is, at the start of operation, the head and the magnetic storage surface are set in a contact state, and then a space for air is created between the head and the magnetic storage surface by applying the required rotation to the magnetic storage device lζ, and recording is performed in this state. This is a method of playback (contact start-stop method).

(hereinafter referred to as the C8S method). In this method, the magnetic storage body stops rotating at the end of the operation, and at this time the head and the magnetic storage body surface are in the same frictional state as at the start of the operation.

The frictional force generated between the head and the magnetic storage body in these contact friction states can wear out the head and the magnetic storage body, and may eventually cause damage to the head and the magnetic medium. Further, in the contact friction state, a slight change in the posture of the head may cause the load applied to the head to become uneven, causing scratches on the surface of the head and the magnetic storage body.

In order to prevent the occurrence of this scratch, Japanese Patent Laid-Open No. 52-498
Various lubricants have been proposed, including the following side-chain perfluoroalkyl polyethers or linear perfluoroalkyl pholyethers as shown in No. C8 removed many times
It was not possible to prevent the occurrence of scratches on the magnetic storage body by repeating S.

Another drawback is that the removed lubricant is thickly localized on the contact sliding surface, causing adhesion due to contact between the head and the magnetic storage body, making it difficult to separate.

F, Co÷CF t -CF 2-0←÷CF, -0+
C.F.

m n Linear Perfluoroalkyl Polyether (Object of the Invention) An object of the present invention is to provide a magnetic memory having a lubricating layer that has excellent lubrication properties and does not cause adhesion between the head and the disk.

(Structure of the Invention) That is, in the magnetic storage body of the present invention, a magnetic medium is coated on a base body having a mirror surface, and a lubricant made of a lubricant containing a perfluoroalkyl phosphorus compound is applied onto the medium directly or through a protective film. It is characterized by having a structure in which layers are coated.

(Detailed explanation of configuration) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a partial sectional view of the magnetic storage body of the present invention, in which the base body 1
is aluminum alloy, anodized alumite, N1-p plating film, crJ'eNi, aluminum alloy coated with MO or W, or plastic such as polyester, polyimide polyamideimide, or Cr.

It is a metal such as FeNi, MO, W, or a glass plate.

Next, a magnetic medium 2 of Fe, 04r
-Fe, 0. , or Co-Ni, C
o-N1-P, Co-hlln-P, Co
-Ni-Mn-P, Co-Re, ('o
7Mn-Re-P+C0-Cr, Co-V, Co-Pt
, C0-Ni-Pt, Co-Pt-Cr, Co-Pt-
Coating metals or alloys such as V, Co-Rh, Co-N1-Mo or Co-8m.

Further, the magnetic medium 2 is coated with a lubricating layer made of a lubricant containing a perfluoroalkylphosphorus compound. The perfluoroalkylphosphorus compound used here has the following structure.

R [＼ ＼ ＼ ＼ ＼  f'-P... ■ R(' -PO...
■Rf/Rf"/ Here, Rf, Rf', Rf' are Cn F tl, +s
(CHt)m or (nF!n+□÷Rf''-J) is a fluorinated hydrocarbon such as camphor or perfluorophenyl group.

Further, n and p are integers of 1 or more, and m is 0 or an integer of 1 or more. Further, J is a bonding molecule such as 10-1-.

Further, Rf# has a perfluoroalkyl group such as CnFzn-s- in the side chain, or is a straight-chain perfluoroalkyl group.

Further, examples of the lubricant used in the present invention include perfluoroalkyl polyether, perfluoroalkyl polyether having a functional group, polytetrafluoroethylene, polytetrafluoroethylene telomer perfluorocarboxylic acid, perfluoroalcohol, and perfluorocarboxylic acid. acid ester, fatty acid ester of perfluoroalcohol, perfluoroalkylalkoxysilane, fluorosilicone, perfluoroalkylsulfonic acid, ammonium perfluoroalkylsulfonate, aliphatic alkylalkoxysilane, higher fatty acid, higher fatty alcohol, higher fatty acid ester, These include higher fatty acid amide fatty amines, unsaturated higher fatty acids, long chain aliphatic hydrocarbons, polyalkylene glycols, silicone oils, polyoxyethylene, neopentyl polyol esters, polyphenyl ethers, etc.

FIG. 2 is a partial cross-sectional view of another magnetic storage body of the present invention. In FIG. 2, the base body 1. and magnetic media 2. The lubricating layer 4 is the same as that shown in FIG. 1, but a protective film 3 is coated between the magnetic medium 2 and the lubricating layer 4.
is 5i02+S'sN4+SiC or a silicon compound such as a silicic acid polymer or COO.

Co, 04tCo203. a-Fe20s +CrtO
s + metal oxides such as CrO3, TiO7, or z02 or TiN.

Metal nitrides such as ZrN, CrN or TaN or Ti
Metal carbide such as CZrC, CrC or TaC or W
Metals or alloys such as Cr, Ir, NiP, Ru, Rh, Mn, MO, O5 or Ta or alloys thereof are used. The perfluoroalkyl phosphorus compound strongly adsorbs to the magnetic medium 2 or the protective film 3 and has good compatibility with the lubricant, so it can be mixed with the lubricant to prevent scratches caused by sliding between the head and the disk. In addition, by preventing the lubricant from accumulating on the sliding surfaces of the head and disk, it is possible to prevent the disk from adhering to the head.

Next, the present invention will be explained in detail with reference to Examples.

Example 1 Covered with nickel-phosphorus plating film with surface roughness of 0.02 μm
A cobalt-nickel-phosphorus alloy was plated to a thickness of 0.05 .mu.m as the magnetic medium 2 on the base body 1, which had a mirror finish. Next, a protective film 3 is formed on the magnetic medium 2 using a polysilicate film as disclosed in Japanese Unexamined Patent Publication No. 52-20804.
Silicic acid polymer) is coated by a spin coating method. Next, 0.1% by weight of a mixture of a perfluoroalkyl phosphorus compound with the following structure and a lubricant with the following structure was placed on top of this protective layer 3.
A lubricating layer was formed by coating a solution of J chloride, IJ fluoroethane (hereinafter referred to as Freon) by a spin coating method, and a magnetic disk was produced.

Perfluorophenyl phosphorus compound lubricant FsC-0+CFt CFt O++CFt O+CF
sts ts Example 2 A magnetic disk was made in the same manner as in Example 1, except that a perfluoroalkylphosphorus compound having the following structure and a lubricant were used.

Perfluorophenyl phosphorus compound lubricant Hs COOCCF 20÷CF, CF2O÷−←CF
2Os.

CFzCHtCOOCHs Example 3 Same as Example 1 except that 50% NiP was used as the protective film 3.
0^ plating and then firing at 280°C to form NiO on the surface to produce a magnetic disk.

Example 4 Same as Example 3 except that S'02 was used as the protective film 3.
A magnetic disk was produced by coating by 00A sputtering.

Example 5 A magnetic disk was produced in the same manner as in Example 2, except that the magnetic medium 2 was coated with a C0Cr alloy by sputtering.

Example 6 Same as Example 2 except that r -Fe was used as the magnetic medium 2.
,0. A magnetic disk was made by coating the material by sputtering.

Example 7 A magnetic disk was produced in the same manner as in Example 1, except that a perfluoroalkylphosphorus compound having the following structure was used.

Comparative Example 1 A magnetic disk was produced in the same manner as in Example 1, except that only a lubricant was applied as a lubricant layer 4' on the protective film 3.

Comparative Example 2 A magnetic disk was produced in the same manner as in Example 1, except that only a lubricant was applied as the lubricant layer 4 on the protective film 3.

A contact start/stop (C8S) repeated wear test was performed many times using a head slider having an Atzos-Tica core with a load of 15 f using the magnetic TiSF shown in Examples 1 to 7 and Comparative Example 1.2; 1000
The adhesion between the head and the disk after repeating C8S was evaluated by measuring the coefficient of friction, and the results shown in the following table were obtained.

From the results shown in the table above, the magnetic disks having a lubricating layer made of a mixture of a perfluoroalkylphosphorus compound and a lubricant in Examples 1 to 7 are different from the magnetic disks having a lubricating layer not containing a perfluoroalkylphosphorus compound in Comparative Examples 1 and 2. It can be seen that the mechanical durability is dramatically improved compared to disks, and there is no possibility of adhesion between the head and the disk drive.

(Effects of the Invention) As described above, the magnetic disks having a lubricant layer made of a lubricant mixture containing a perfluorophenyl phosphorus compound shown in Examples 1 to 7 have excellent mechanical durability and adsorption between the head and the disk. It has been found that it has a preventive effect and can dramatically improve the reliability of magnetic disk drives.

In the embodiments of the present invention, magnetic disks have been described, but it is clear that the present invention is also effective for floppy disks, magnetic tapes, and magnetic cards.

[Brief explanation of drawings]

1 and 2 are partial cross-sectional views showing the present invention. DESCRIPTION OF SYMBOLS 1... Base body, 2... Magnetic medium, 3... A-retaining film,
4... Lubricating layer. , how- -one

Claims (1)

[Claims] 1. A magnetic memory having a structure in which a magnetic medium is coated on a base body, and a lubricant containing a perfluoroalkyl phosphorus compound is further coated on the medium directly or through a protective film.