JPS61178724A - Magnetic storage body - Google Patents

Abstract

PURPOSE:To obtain the titled magnetic storage body having an excellent lubricating characteristic by coating a fluorinated hydrocarbon polymer contg. >=1 repeating unit consisting of a hydrocarbonic chain or a mixture of the polymer and a lubricant on the magnetic medium. CONSTITUTION:Iron oxide such as Fe3O4 and gamma-Fe2O3 or a metal or an alloy such as Co-Ni and Co-Ni-p is coated on a substrate body 1 as a magnetic medium 2. Moreover, a lubricating layer 4 consisting of a fluorinated hydrocarbon polymer contg. >=1 repeating unit consisting of a hydrocarbonic chain or a mixture of the polymer and a lubricant or a fluorinated hydrocarbon polymer contg. >=1 cyclic structure or a mixture of the polymer and a lubricant is coated on the magnetic medium 2. A compd. having the structure shown by formula 1 is exemplified and used as the fluorinated hydrocarbon polymer contg. >=1 repeating unit consisting of a hydrocarbonic chain. Besides, a compd. having the structure shown by formula 2 is exemplified as the fluorinated hydrocarbon polymer contg. >=1 cyclic structure.

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) In general, there are the following methods for recording and reproducing a magnetic storage device including a recording and reproducing method head (hereinafter referred to as a head) and a magnetic storage body. In other words, at the start of operation, the head and the magnetic storage surface are set in contact, and then the required rotation is applied to the magnetic storage to create a space for air between the head and the magnetic storage surface, and in this state recording is performed. This is a method of playback (contact start-stop method).

(hereinafter referred to as the 088 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.

Further, the head and the magnetic storage body are attracted to each other due to contact for a long time, and become difficult to separate. In order to prevent the occurrence and adsorption of scratches, various types of lubrication have been used, including side chain perfluoroalkyl polyethers or linear perfluoroalkyl polyethers having the structure shown below, as shown in JP-A-52-49805. Several agents have been proposed, but in all cases, the lubricating layer is gradually removed by 088, and it has not been possible to prevent the occurrence of scratches on the magnetic storage body even after repeated CSS many times. In addition, the removed lubricant is thickly localized on the contact sliding surface,
It also has the disadvantage of causing adhesion to the head.

F, Co(-CF, -CF, -0 ring≠CF, -0 rabbit C
F.

Linear Perfluoroalkyl Polyether (Object of the Invention) The object of the present invention is to provide a lubrication material that has excellent lubrication properties, has less head adhesion, and has good adhesion to the surface of the magnetic memory (that is, does not deteriorate the floating characteristics of the head). An object of the present invention is to provide a magnetic memory having a magnetic agent.

(Structure of the Invention) That is, the magnetic storage body of the present invention has a magnetic medium coated on a base body having a mirror surface, and contains one or more repeating units consisting of hydrocarbon chains on the medium directly or via a protective film. A magnetic memory having a structure coated with a lubricant layer made of a fluorinated hydrocarbon polymer or a mixture of the polymer and a lubricant, and a fluorinated hydrocarbon polymer or a mixture of the polymer and a lubricant containing one or more cyclic structures. This magnetic memory is characterized by having a structure in which it is coated with eight layers consisting of:

(effect) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a partial cross-sectional view of the magnetic storage body of the present invention, in which the base body l
is aluminum alloy, anodized alumite, N1-P plated film, aluminum alloy coated with Cr, FeNi, Mo or W, or plastic such as polyester, polyimide, polyamideimide, polysulfone, aromatic polyether, or Or, FeNi, Mo.

It is a metal such as W or a glass plate. Next, this base body l
Pa104. iron oxides such as r-Fez (%) or Co-Ni, Co-Ni-P, C
o-Mn-P.

Co-Ni-Mn-P, Co-Re, Co-Mn-R
e-P, Co-Cr, Co-V.

Co-Pt, Co-Ni-Pt, Co-Pt-C
r, Co-Pt-V, Co-Rh.

Coating a metal or alloy such as Co-Ni-Mo or Go-8m. Further, on the magnetic medium 2, a fluorinated hydrocarbon polymer containing one or more repeating units consisting of a hydrocarbon chain or a mixture of the polymer and a lubricant, or a fluorinated hydrocarbon polymer containing one or more cyclic structures or the polymer. A lubricating layer 4 consisting of a mixture of lubricants is coated.

An example of the fluorinated hydrocarbon polymer containing one or more repeating units consisting of a hydrocarbon chain used in the present invention is a compound having a structure as shown in the following formula.

n-J″(-n(-J +;+a/+J/St→;?
...■R/ is a fluorinated hydrocarbon -Ch(ChF'z
k+x) -h (h is an integer of 1 or more, k is 0 or a multiplier of 1 or more)
m or n is an integer u of 1 or more, tt' is CtXzt+t (i is an integer of 1 or more, There is a compound with the following structure:
...■Each symbol is the same as that expressed in formula 0. p
is 0 or 1. However, M' is -Cf- where X is H, F, CI, Br, I,
R” is CtX2t (t is 0 or an integer of 1 or more) or 0 to
Formula 0 may contain a functional group.

Effective functional groups are -NCO, -8H, -80,H, -80,M (M is Na
, to, Li), -cN.

-COOC3Ht j +t (j is an integer greater than or equal to 1)
, -CiHt30H (I is an integer of 0 or 1 or more),"
Hlt-CH1=CHl.

-s+ (ChHth+1)gXs = g (h is an integer greater than or equal to 1, g is 0, 1 or 2, X is CJ or -OH
or QC(Htf+1 (f is an integer of 1 or more)), or -Am5I(chHth+t) g xs = g(h
pgtx is the same as above. Writers are C, H, N, 0, 8-1
(organic substances consisting of three or more elements).

For example, -〇〇-NH-OH, -CH,-, -NH-CH
, -CI((OH)-CH!-CH!-, -NH-CO
-CH, -CH, -, -0-OH! - The functional group G in the above general formula is a magnetic medium 2 or a magnetic medium z as shown in FIG.
Since it strongly reacts and adheres to the protective film 3 formed thereon, it is not removed by sliding of the head. This effect is particularly evident among functional groups -8i (CbHt h+t)gL
= g (h is an integer greater than or equal to 1, g is 0, 1 or 2, X is C
The amount of silane represented by I or -OH or 0CfHtf+1 (t is an integer of 1 or more) also has an effect. Further, the annular structure included in the formula 0 is attracted to and fixed to the magnetic medium 2 or the protective film 3. In addition, the fluorinated hydrocarbons in formulas ■ and ■ lower the surface energy, reduce adhesion between the head and disk, have a sustained lubricity effect that prevents scratches due to sliding between the head and the disk, and accumulate a lubricant layer between the head and disk. Two effects can be obtained at the same time: preventing the head from sticking to the disk and preventing the head from sticking to the disk. The viscosity of the above perfluoroalkyl polyether is 10 to 1,000,000c@ depending on the molecular chain length and the type of functional group.
It can be changed up to t. Examples of lubricants to be mixed with the fluorinated hydrocarbon polymers shown in formulas 0 to 0 include monotyl, polytetrafluoroethylene, polytetrafluoroethylene telomer, and perfluorocarboxylic acid.

Perfluoroalcohol, perfluorocarboxylic acid ester, fatty acid ester of perfluoroalcohol, perfluoroalkylalkoxysilane, fluorosilicone, perfluoroalkylsulfonic acid, ammonium perfluoroalkylsulfonate, aliphatic alkylalkoxysilane, higher fatty acid, higher grade fatty alcohols, higher fatty acid esters,
These include higher fatty acid amide fatty amines, unsaturated higher fatty acids, long chain aliphatic hydrocarbons, polyalkylene glycols, silicone oils, polyodiethylene, 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, magnetic medium 2, and lubricant layer 4 are the same as in FIG.
A protective film is coated in between. The protective film 3 is made of Yata H,
9i1N4.8iC or silicon compounds such as silicic acid polymers or CoO# Cogo,.

Cog(%@α-Fl!! 03 p Crz Os,
Cr01 g Tl (% g or zro.

Metal oxides such as TiN, ZrN, CrN or T
Metal nitrides such as aN or gold true carbides such as TiC, ZrC, CrC or TaC or W, Cr, I
r, NiP, Ru, Rh.

Metals or alloys such as Mn, Me, Os or Ta or alloys thereof are used.

Both react well with the lubricant layer 4 and firmly form the lubricant layer 4.
can be held. In particular, nickel oxide, cobalt oxide, or 8i0* has a remarkable effect.

After coating with the lubricating layer 4, it may be fired at a temperature of 00 to 300°C.

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 μm as a magnetic medium 2 on a mirror-finished base body 1. Next, polysilicic acid (silicic acid polymer) as disclosed in Japanese Patent Application Laid-Open No. 52-20804 is applied as a protective film 3 onto the magnetic medium 2 by a spin coating method. Next, on this protective film 3, a fluorinated hydrocarbon polymer having the following structure was used as a lubricating layer 4, where m:10 and n=50. 0.
A magnetic disk was prepared by coating with a 1-tS trifluorotrichloroethane (hereinafter referred to as Freon) solution by spin coating. When this magnetic disk was evaluated using the evaluation method described below, it was confirmed that it had excellent durability.

Example 2 A magnetic disk was fabricated in the same manner as in Example 1, except that the lubricant layer 4 was made of a fluorinated hydrocarbon polymer having the following structure.

Here, m:20, n"20.

Example 3 Same as Example 1, except that a fluorinated hydrocarbon polymer having the following structure was used as the lubricating layer 4, where m: 10
, H=20.

Example 4 A magnetic disk was produced in the same manner as in Example 1, except that perfluoroalkyl polyether having the following structure was used as the lubricant layer 4.

F, C (-Crt-0-C horse-+-C city where m=5
It is 0.

Example 5 A magnetic disk was manufactured in the same manner as in Example 1, except that a fluorinated hydrocarbon polymer having the following structure was used as the lubricating layer 4. Here, H=lO, m=lO.

Example 6 A magnetic disk was manufactured in the same manner as in Example 1, except that the lubricant layer 4 was made of a fluorinated hydrocarbon polymer having the following structure.

F, C+◎→Ya←(4F4-0-CFx - Tomo CFs
Here n: 20. m"10.

Example 7 A magnetic disk was made in the same manner as in Example 1, except that perfluoroalkyl polyether having the following structure was used as the lubricant layer 4. Here, n=10. m=20.

Example 8 A magnetic disk was produced in the same manner as in Example 1, except that perfluoroalkyl polyether having the following structure was used as the lubricant layer 4.

Here, n=1Q and m=15.

Example 9 A magnetic disk was produced in the same manner as in Example 1, except that NiP was plated at 500° as the lubricating layer 4 and the protective film 3, and then fired at 280° C. to form NiO on the surface.

Example 1O Same as Example 3 except that the lubricating layer 4 and the protective film 3 were 8i0. A magnetic disk was produced by coating the material by 200λ sputtering.

Example 11 The magnetic medium 2 was coated with a CoCr alloy 2 by sputtering, and its surface was coated with water fU-2 in the same manner as in Example 1.
As Example 4, a magnetic disk was produced by coating the same lubricating layer as in Example 7.

Example 12 Same as Example 11 except that r −F was used as the magnetic medium 2.
A magnetic disk was made by coating c2os by sputtering.

Comparative Example 1 Same as Example 1 except that lubrication Jj14 was applied on top of the protective film 3.
A magnetic disk was made by coating perfluoroalkyl polyether having the following structure.

n=30-50 Comparative Example 2 A magnetic disk was made in the same manner as in Example 1, except that a perfluoroalkyl polyether having the following structure was coated on the protective film 3 as the lubricating layer 4.◎p, c+c ,ii'
,-o+(-Crt-0+-CPsm"n:2
Using a head slider having a core of 0 to 30, a contact start/stop (CSS) repeated wear test was performed many times and the critical film thickness at which head adsorption begins was measured, and the results shown in the following table were obtained.

From the results in the table above, it was found that the durability of the fluorinated hydrocarbon polymers of Examples 1 to Z2 was significantly improved compared to the perfluoroalkyl polyether of Comparative Example 1.2.

Since Examples 11 and 12 did not have a protective film, their durability was worse than other Examples, but they had better durability than Comparative Examples. Regarding the critical film thickness, the perfluoroalkyl polyethers of Comparative Examples 1 and 2 start adsorption to the head even with a very small film thickness, but the fluorinated hydrocarbon polymers of Examples 1 to 14 are thicker at 80 to 150 mm. It was found that head adsorption did not occur up to the film thickness and that there was a large margin.

(Effects of the Invention) As described above, it has been found that the magnetic storage body of the present invention is made of fluorinated hydrocarbon polymer, has excellent durability, is resistant to head adhesion, 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 examples of the present invention. DESCRIPTION OF SYMBOLS 1... Base body, 2... Magnetic medium, 3... Protective film,
4... Lubricating layer. (,1,.

Claims (2)

[Claims] (1) A magnetic medium is coated on the substrate, and a fluorinated hydrocarbon polymer containing one or more repeating units consisting of a hydrocarbon chain or a lubricant is further coated on the medium, either directly or through a protective film. A magnetic memory having a structure coated with a mixture. (2) A magnetic medium is coated on the base body, and a fluorinated hydrocarbon polymer containing one or more cyclic structures or a mixture of the polymer and a lubricant is further coated on the medium directly or via a protective film. A magnetic storage body characterized by having a structure.