JPS5841438A - Medium of magnetic disk - Google Patents

Abstract

PURPOSE:To make a medium withstand long-term use and use under high-speed rotation by applying a specified high molecular substance with low energy to the surface of the medium as a lubricant. CONSTITUTION:A compound represented by the general formula[where n is 10-100, M is an org. base such as NH2(R)NH, (R)NH2 or (R)3N, a metallic base of Na, Ca, K, Ba or the like, or H]is dissolved in CFCl2-CF2Cl or the like, and the soln. is applied to the surface of the magnetic medium of a magnetic disk and baked.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk medium coated with a low-energy polymer lubricant to reduce friction.

Recently, in magnetic disk drives using coated magnetic disks, a ``contact start-to-start'' system has been adopted in which the magnetic head slides on the surface of the magnetic disk without making contact with it. Therefore.

A method is used to reduce wear between the magnetic head and the magnetic disk by coating the surface of the magnetic disk with a thin layer of low-energy polymer material for lubrication.

Currently, the low-energy polymeric lubricant commonly used in coated magnetic disk media is F-[CF(CF3)CF20]nC2F5 (manufactured by DuPont).
(product name Krytox) and CF3 manufactured by Montenoson.
-([0-CF(CF3)-CF2,)x-0-CF
'2) The main ones are n-0・CF3 (trade name: Phoneprin). but.

These low energy polymer materials are liquids.

It remains in a liquid state even after being applied to the surface of a magnetic disk. However, in magnetic disk devices.

Because magnetic disks are used at high speeds, the liquid lubricant is blown off by centrifugal force during high-speed rotation, and the coating thickness decreases over time. If the degree of decrease in coating thickness is dh/dt, then the removal f' can be expressed by the following equation. Here, ρ is the specific gravity of the lubricant, η is the viscosity of the lubricant, h is the coating thickness, and ω is the angular velocity. From this formula,
For example, the lubricant applied with 1000λ is 360λ
3 years at Orpm.

When rotated at 38° C., the p 400 A decreases.

However, actual measurements show that the reduction in the coating thickness of the lubricant in the currently commonly used coating media is smaller than that of the predecessor. The reason for this is thought to be that the lubricant is buried in the rough surface of the medium. However, in recent years, with the aim of achieving higher density recording, the roughness of the media surface has been eliminated, and the reduction in coating thickness has gradually come closer to that of its predecessor. For example, in plated disks and S/E 7 disks, which are continuous thin film media, the roughness of the two surfaces is always better than that of coated media, and the reduction in coating thickness is even closer to that of the former. Therefore, even if the thickness of the lubricant is increased in order to reduce the loss of the amount of lubricant applied during use, the initial loss will only increase and the lifespan will not be extended much, and if more than the appropriate amount is applied, There are disadvantages in that failures occur due to lubricant scattering when the disk rotates, and the magnetic head sticks to the medium surface when the disk rotation stops.

The object of the present invention is to provide a high-quality lubricant that does not reduce the coating thickness even after long-term use, and that does not scatter when the disk rotates or cause the magnetic head to stick to the medium surface even when the rotation is stopped. The present invention provides coated magnetic disk media.

According to the present invention, n is 10 to 100 and 2M is NH2
Organic bases such as (R)NH, (R)NH2, and (R)3N, or metal bases such as Na r Cat K p Ba, or compound materials obtained by the quadratic formula % formula % when H is used as a medium. A magnetic disk medium is obtained, which is characterized in that it is attached to the surface.

Next, two examples of magnetic disk media according to the present invention will be described.

1. To create compound materials.

CF, CF5 is taken up and subjected to an esterification reaction with a primary amine salt NH2C6 and acidic hydrochloric acid.

F3CF3 is obtained. This compound k is dissolved in CFCl2-CF2Cl to form a 0.26Q% solution and then applied to the surface of a spreadable medium by spraying. Thereafter, baking was performed at 130° C. for 0 minutes. After cooling, wipe the magnetic disk with a lint-free cloth while rotating it at the same time. In addition, -1-
In this article, the method of applying the compound is described.

For example, Japanese Patent Application No. 51-39743 and Japanese Patent Application No. 54-
1: (Applying the method filed in No. 5957 (/1) This prevents the surface of the disk medium from being coated in spots, and also coats the disk medium uniformly to an arbitrary thickness. be able to.

In the above embodiment, in the above equation (0), M is
However, which base to select for M depends on the type of coating and the quality of the medium surface such as meth, ki, su, vine, etc. 2 The base that has the strongest bonding strength with this may be selected. Furthermore, if reactive groups are present on the medium surface due to baking after coating, the ester moieties will react.

Forms a strong film on the media surface. After cleaning the media surface thoroughly, even if there are no reactive groups present.

If a lubricant is applied and baking is performed, a fairly strong film can be obtained due to the intermolecular attraction of the ester moieties. Furthermore, by wiping after baking, excess lubricant is removed and a near-lubricant film is formed on the monomolecular film.

According to the data obtained by the above examples.

The combination of a magnetic disk and an MnZn bulk type magnetic head (10g load) allows no physical damage to the head or medium surface even after 20,000 starting and stopping cycles. Ta.

Furthermore, even if the apparatus was left stopped for one week, no adhesion phenomenon occurred between the medium surface and the head.

Claims (1)

[Claims] 1, n'! 1=10 to 100 and 2M is NH2(R)
N.H. Organic bases such as (R)NH2, (R)5N, or Na
1. A magnetic disk medium characterized in that a metal base such as CarK/Ba or a compound material obtained by a linear formula when H is attached to the surface of the medium.