JPS5917215A - Magnetic recorder and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture the magnetic recorder with a Co-Cr group vertical magnetizing film on a base material even when the temperature of the base material is the normal one by mixing a small amount of P to the Co-Cr group vertical magnetizing film on the surface of the base material. CONSTITUTION:A material in which the small pieces of a Co-P alloy are arranged uniformly on a material surface of a tabular shape, etc. of a Co-20wt% Cr alloy displaying the most excellent vertical magnetization characteristics is used as a target, and the material is sputtered through a normal DC magnetron sputtering method, and precipitated at a precipitation rate of 6,000Angstrom /mm. on the surface of the base material at the normal temperature consisting of the sheet of PET. The surface of the base material is bonded with a cooled holder to prevent a temperature rise during sputtering. Accordingly, the Co-Cr vertical magnetizing film, which has the thickness of 4,000Angstrom and into which approximately 4wt% P is mixed, is obtained on the surface of the base material made of polyethylene terephthalate. It is preferable that the quantity of P to be added is inhibited to approxmately 5% or less.

Description

[Detailed Description of the Invention] In recent years, perpendicularly magnetized films with magnetic anisotropy in the perpendicular direction have been developed as high-density recording media, and 0o-Or perpendicularly magnetized films are particularly excellent in practical use. Magnetic recording bodies deposited on the surface of a substrate are known.

However, in order to manufacture this magnetic recording medium, a 0o-Or magnetized film is deposited on the substrate surface at a deposition rate of several thousand A to several μ's/ml11 using a vapor deposition method, a magnetron-type high-speed sputtering method, or the like. When generating
It has been found that a perpendicularly magnetized film cannot be obtained unless heated close to the surface.This means that this manufacturing method requires heat-resistant materials such as polyethylene terephthalate (PET), which is commonly used in magnetic tapes, floppy disks, etc. A disadvantage is that weak synthetic resins cannot be used as base materials.

From an industrial production scale, generally, without heating the substrate,
It is desirable to be able to form a 0o-Or perpendicular magnetization film at high speed at room temperature.

The present invention provides a new magnetic recording material having a 0o-Or perpendicular magnetization film even at room temperature,
It is characterized by a small amount of P being mixed into the perpendicularly magnetized film.

Furthermore, the present invention provides a manufacturing method that achieves the above requirements by making it possible to manufacture a magnetic recording material having an 0o-Or perpendicular magnetization film even when the substrate is at room temperature. Or, apply 0o-Or on the substrate surface heated to 200°C or less.
It is characterized by precipitating a mixture of mainly magnetic particles and a small amount of P or P alloy particles at a rate of several thousand to several μm/qiy+.

Next, the present invention will be explained in detail.

Using a target with small pieces of Oo-P alloy arranged uniformly on the surface of a plate-shaped material such as an Oo-20wt%Or alloy that exhibits the best perpendicular magnetization characteristics, this is sputtered using the usual DO magnetron sputtering method. Deposition is performed on the surface of a base material made of a PET sheet at room temperature at a deposition rate of 6000 A/mix. The surface of the base material was adhered to a cooled holder to prevent temperature rise during sputtering. In this way, a 0o-Or perpendicular magnetization film having a thickness of 400 OA and containing about 4 wt% of P was obtained on the polyethylene terephthalate base material surface. Using the same manufacturing method, however, in order to vary the amount of P mixed, 00-
Various types of 0o-O with various mixed amounts by changing the amount of P alloy small pieces
A product with a precipitated film was obtained. For comparison, the above 0
Conventional 0o-20at%O without placing o-P alloy pieces
A magnetic recording body having a conventional 0O-or magnetization film was obtained by sputtering in the same manner using only the r alloy as a target.

We measured various magnetic properties of these sun blues,
The results shown in the figure were obtained.

As is clear from the internuclear space, in the conventional case without phosphorus addition,
Coercive force Hci perpendicular to the film surface and coercive force HO parallel to the film surface
// is 1, as shown in their respective characteristic curves A and B,
They are almost the same and do not form a perpendicularly magnetized film, but as phosphorus is added and the amount of addition increases, the HO value increases rapidly, the value of J(direction/Ho□) also increases, and the perpendicularly magnetized film increases. It can be seen that a film that can be formed and increases in size can be obtained. However, when M
As shown in the characteristic curve C, it was found that the value of s becomes non-ferromagnetic at around 5.5%. As a result, for a perpendicularly magnetized film, the amount of P added can be as small as about 5% or less! It is preferable to apply it.

The cause of the formation of this perpendicularly magnetized film is estimated as follows. In other words, since phosphorus segregates at the grain boundaries of precipitated grains, the grains become isolated and become single-domain grains, which increases the shape anisotropy and changes the magnetization process from domain wall movement to rotation, resulting in the retention in the vertical direction. This is to increase magnetic force. Also, the reason why phosphorus segregates at grain boundaries is that phosphorus is an element that is inherently easy to segregate and diffuse even at low temperatures, and also because the bond with Or is larger than the bond with OO. This is thought to be because phosphorus also precipitates along with the Or atoms segregated in O as described in 11 above. As a human material, P-Oo gold alloy may be used, other phosphorus alloys may be used, and it is not limited to solid materials.
A gaseous substance may be used as PH, gas, etc. In this case, A
A method may also be adopted in which the gas is introduced into the vacuum processing container simultaneously with the r gas.

In addition to the above-mentioned sputtering method, vapor deposition method, ion blating method, and other suitable thin film forming means can be adopted.
In addition to alloys, it includes tubes to which small amounts of conventionally used metals such as 00~0r10~b W, Ti, V, Rh, etc. are added.

It has been found that the temperature of the substrate can be raised without cooling by adding a small amount of phosphorus, and that a perpendicularly magnetized film can be obtained even when the temperature of the substrate is increased to a relatively low temperature of 200° C. or less. Of course, a heat-resistant base material is used to produce a magnetic recording body having the 0o-Or perpendicular magnetization film of the present invention mixed with phosphorus.

According to the present invention, a 0o-Or perpendicular magnetization film can be obtained by mixing a small amount of phosphorus, and it is possible to use even synthetic resins with poor heat resistance as a base material, and it is suitable for high-speed, large-scale mass production. This method has the advantage that a Co-Or based perpendicular magnetization film type magnetic recording material can be obtained by the precipitation method.

[Brief explanation of drawings]

The drawing is a graph showing the relationship between various magnetic properties of the 0o-Or perpendicular magnetization film of the present invention and the amount of phosphorus added. A...Characteristic curve of perpendicular coercive force B...Characteristic curve of parallel coercive force C...2 people outside the M8 characteristic curve 2 bald force σ amount (W/N procedure amendment book Showa 57. Ui5 Mr. Commissioner of the Japan Patent Office1, Indication of the case Patent Application No. 125042 of 19822, Name of the invention Magnetic recording medium and its manufacturing method3, Person making the amendment Relationship with the case Patent applicant Japan Vacuum Technology Co., Ltd. 4, Agent 6, Column 7 of "Detailed Description of the Invention" of the specification to be amended, page 1, line 15 of the specification of the contents of the amendment. The perpendicular magnetic recording method and the magneto-optical recording method are attracting attention as methods, and we will correct them as "recording media for them."

Claims (1)

[Scope of Claims] 1. A magnetic recording body characterized in that a small amount of P is mixed in an Oo-Or perpendicular magnetization film on a substrate surface. 2. The magnetic recording material according to claim 1, wherein the amount of P mixed is about 5 wt% or less. On the unheated or heated substrate surface below 200°C,
1. A method for producing a magnetic recording material, which comprises depositing Go-Or based magnetic particles and a small amount of P or P alloy particles at a rate of several thousand A-several μm/rnm.