JPH01258215A - Magnetic memory medium and its production - Google Patents

Abstract

PURPOSE:To obtain the magnetic memory medium having high mechanical reliability by coating a magnetic metallic medium on a substrate, coating a thin film consisting of one kind of material selected from oxides, etc., on this medium and coating a mixture contg. one kind of the alcoholates of prescribed metals and a polyether fluoride polymer having an isocyanate group on the thin film. CONSTITUTION:The metallic medium is formed on the substrate and the thin film consisting of at least one kind of the material selected from oxides, nitrides, carbides, and carbon is formed on this medium. The mixture contg. at least one kind of the metal alcoholates of Ti, Zr, Hf, Nb, and Ta and the polyether fluoride polymer having the isocyanate group is formed on this thin film. The oxides, nitrides and carbides are the compds. of the element selected from Al, B, Y, etc., and the metal alcoholates are Ti(OC4H9)4, Zr(OC4H9)4, etc., and the polyether fluoride polymer having the isocyanate group is the polymer expressed by the formula, etc.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a magnetic storage body (hereinafter referred to as a storage body) used in a magnetic recording device (magnetic disk device, magnetic drum device, and magnetic tape device) and its manufacture. Regarding the method.

[Conventional technology]

A storage body with a metal magnetic medium (hereinafter referred to as a metal medium) must have sufficient mechanical reliability to withstand contact with a recording/reproducing head (hereinafter referred to as a head) and must be free from moisture, chlorine, etc. Corrosion resistance that can withstand corrosive environments is required.

Conventionally, the substrate used is an At alloy substrate that has been subjected to a non-magnetic plating treatment such as alumite treatment or N1-P plating, and then polished for mirror polishing and marking, and then N1-P,
After non-magnetic plating such as N, 1-Ou-P and coating with Or, Bi, etc., a ferromagnetic metal medium is coated, and then Sin,
(including polysilicic acid), A/, N, 0.81. N, and *2,0. A protective film such as a solid solution of
A thin layer of a liquid lubricant such as 0-Robolyte or a solid lubricant such as higher alcohol or fatty acid is coated.

Although the above-mentioned memory bodies have a certain level of durability and have already begun to appear on the market, they have major drawbacks.

If a drive equipped with the above memory element is left in an environment of 40°C, 80% R, H, corrosion points will occur in one or two places on each memory element. It leads to i7 ect error. Furthermore, due to repeated contact between the storage body and the head, the coefficient of friction between the two increased, often causing the spindle motor to stop.

(Problems to be Solved by the Invention) The conventional technology had the problem that it was not possible to sufficiently ensure the corrosion resistance of the metal medium, and that it was not possible to sufficiently ensure the mechanical reliability between the storage body and the head.

The present invention solves the above problems, and its purpose is to dramatically improve the corrosion resistance of metal media in environments containing moisture and chlorine, and to improve the coefficient of friction between the storage body and the head. The purpose of the present invention is to manufacture and provide a highly reliable memory body that can significantly reduce the amount of water and maintain its effect for a long period of time.

[Means to solve the problem]

The storage body and manufacturing method of the present invention include forming a metal medium on a substrate, forming a thin film made of at least one substance selected from oxides, nitrides, carbides, and carbon on the metal medium; At least Ti, Zr, H on the thin film
The present invention is characterized in that a mixture containing one of metal alcoholates of f, Nb, and Ta and a fluorinated polyether I polymer having an isocyanate group is formed.

The metal medium is formed using the same materials and manufacturing methods as in the prior art.

Oxides, nitrides, and carbides are kt, B, and Y.

Si, Ti, Zr, l1ifn, 1fb, Ta, Or
.

It is a compound with an element selected from MO and W, and the mixed layer and lamination thereof are arbitrary. Carbon is a mixture of graphite, diamond, and amorphous.

They are laminated, and a film thickness of 100 to 500X is appropriate for both. The above compound and carbon can be formed by a PvD method or an OVD method such as a sputtering method or an ion blating method, and an oxide can also be obtained by coating and baking an organometallic compound.

Next, the metal alcoholate is Ti(0(+4H,)4゜Z
r (oo4a, )4 tTlf (OO+IIIe
)a eMb*(00617)s e Tag (
0ON-R'-Rf-R' -Woo, OH,
-R' -Rf-R-MOO R'; alkylene, cycloalkylene, aromatic group Rf = -01! , -0-(0,1F,O)? &−
(ay,o)m-701P! - a and s are integers of 10 or more.

These include polymers represented by the above formula. The metal alcoholate and the fluorinated polyether polymer are diluted in a soluble solvent, applied by a known manufacturing method such as a spray method, a spinner method, a dipping method, or an ultrasonic atomization method, and baked if necessary. The solvent used was a hepgenated hydrocarbon system,
The concentration is determined depending on the desired film thickness. Although it is not an absolute condition for baking, 1 to 20 minutes at 50 to 150°C is sufficient, and a film thickness of 30 to 200 mm is appropriate.

It should be noted that the metal alcoholate can be applied to a type other than the fully functional type, and the fluorinated polyether polymer can also be used as a polymer having a functional group other than the isocyanate group, such as 7 Ombrine Z.
-DK A II, Z -DOL.

Z-D AO and non-functional polymers, such as Z-AM-s
It is also possible to apply it in combination with eries. (7Onpurine is a product of Montegisson) Also, the mixing ratio of the metal alcoholate and the heptafluorinated polyether polymer is as follows, where the number of functional groups in the former is O1, the number of molecules is P, the number of functional groups in the latter is Q1, and the number of molecules is R. When it is less than 1, the friction performance between the head and the storage body is inferior to the initial state, and when it is 10 or more, although the initial friction performance is excellent, the friction performance is not maintained over a long period of time.

[Effect]

According to the present invention, by forming a thin film made of at least one substance selected from oxides, nitrides, carbides, and carbon, which has excellent hardness and density, on a metal medium, it is possible to protect the head from impact abrasion and reduce environmental pollution. Protects metal media from moisture, chlorine, etc.

However, the above-mentioned thin film is thin, around several hundred times, and it is difficult to make it pinhole-free. Also, among the above thin films, materials other than carbon have poor lubricity, and even the most excellent carbon film has
Because of the insufficient lubricity, it has been common practice to layer various lubricants on a thin film. However, because the adhesion between the thin film and the lubricant is weak, the lubricant is gradually removed from the memory element due to contact wear between the head and the memory element over a long period of time, causing the initial excellent lubrication effect to be lost. I got lost.

In the present invention, the thin film is coated with a mixture containing at least a fluorinated polyether polymer having an isocyanate group and a metal alflate. Metal alcoholates are active groups (-OH) on the outermost surface of oxides, nitrides, carbides, and carbon.

It chemically reacts with -0OOH+ and the isocyanate group of the fluorinated polyether polymer, and has the effect of fixing a lubricating film on the memory medium and preventing it from being removed by impact wear of the head.

In addition, the polyether polymer (7) exhibits excellent water repellency and has the effect of enhancing rust prevention, and for the above-mentioned reasons, this effect is maintained for a long period of time.

As a result of the above, it has become possible to manufacture and provide a memory body with excellent long-term mechanical reliability and storage reliability.

〔Example〕

After applying non-magnetic N1-P alloy plating to a thickness of about 15 μm on a mirror-finished disk-shaped aluminum alloy substrate, the surface was polished to a surface roughness of α02 μm or less, and then Oo-Ni-P alloy plating was applied. It was applied to a thickness of approximately CL05μ.

Next, set the above substrate in a magnetron sputtering device,
After evacuation to below 5X10-'torr, the board was
After heating to ℃ and removing adsorbed moisture, human gas is introduced,
After setting 5X10=torr! ! Films were formed using the materials shown in Table 1 as targets at a power density of 4 W/-.

Next, a mixture of metal alcoholate and fluorinated polyether polymer shown in Table 1 was added to Freon 113 using α20 W.
/7% concentration and dipping method (10eM/7%).
i), and then baked at 110° C. for 10 minutes.

Table 1 The memory bodies obtained by the above manufacturing method were evaluated in the following tests. The results are shown in Table 2.

(aSS durability test) Determine the appearance change, static friction coefficient, and output reduction rate before and after aSS operation. (Head used: Thin film 3370 type, 7 lightite, 115μm, 911L/rx, hour) (Corrosion resistance test) When left in an environment of 85υ 80% R, H, the number of missing pits was measured after the standing time had elapsed, and the number of missing pits was measured. When an increase was observed, the lifespan was judged to have come to an end.

Table 2 [Effects of the Invention] Thin-film memory bodies have been around for a long time as memory bodies compatible with high recording densities, but their use has been limited to some areas due to concerns about long-term reliability.

According to Kinei aAK, even if the memory medium is used under heated and humid conditions, the metal medium will not be affected in any way in practical terms, and will become increasingly hard.
Since the mechanical reliability of the low-fly-hide head is high, even if it is further miniaturized and installed in a drive body used in harsh environments, the characteristics of both the memory body and the head will not deteriorate significantly. I can't admit it.

As described above, manufacturing of highly durable memory bodies compatible with high recording density,
Now available.

that's all Applicant: Seven Ifu Epson Corporation Agent Mogami Patent Attorney (1 other person)

Claims (3)

[Claims] (1) A metal magnetic medium is coated on a substrate, a thin film made of at least one substance selected from oxide, nitride, carbide, and carbon is coated on the metal magnetic medium, and then at least A magnetic memory material coated with a mixture containing one of metal alcoholates of Ti, Zr, Hf, Nb, and Ta and a fluorinated polyether polymer having an isocyanate group. (2) forming a film of metal magnetic medium on the substrate;
forming a thin film made of at least one substance selected from oxides, nitrides, carbides, and carbon on the metal medium;
A method for manufacturing a magnetic memory, comprising the step of forming a film of a mixture containing one of metal alcoholates of Nb and Ta and a fluorinated polyether polymer having an isocyanate group. (3) A film is formed by applying a mixture containing at least one metal alcoholate of Ti, Zr, Hf, Nb, or Ta and a fluorinated polyether polymer having an isocyanate group, and then firing the mixture. 2. The method for manufacturing a magnetic memory body according to claim 1.