JPS58111128A - Manufacture of abrasion resistant magnetic recording material - Google Patents

Abstract

PURPOSE:To enhance abrasion resistance, by subjecting a magnetic film to ion bombarding treatment prior to vapor depositing a higher aliphatic acid or its metal salt on the magnetic film. CONSTITUTION:A magnetic tape (a) is allowed to travel between rollers 2 located in a vacuum chamber in one direction, voltage is applied to an electrode 4 for ion bombardment, for example, gaseous argon is allowed to ion bombard the magnetic tape face (b) to remove impurities of moisture, dust, or the like on the face (b), and the tape is wound on one of the rollers 2. Then, the tape (a) treated by ion bombardment is allowed to travel in the reverse direction, and a higher aliphatic acid or its metal salt 15, such as stearic acid or lithium stearate or the like lubricant, is vapor deposited onto the magnetic film face (b) from a crucible 14. The ion bombardment may be carried out in an atm. contg. an acidic gas.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a magnetic recording medium in which a higher aliphatic acid or a gold jIK base thereof is vacuum-deposited on a magnetic film surface to improve wear resistance.

Recently, obliquely deposited magnetic films, 0o-Or rectangular magnetic films, and O.

High-density film made of a magnetic film of metal or metal oxide, such as Mi P l film, r 1 @ @ OB Suha 7 3%, Ba0-IF・-, sputtered film, formed on a non-magnetic base material such as synthetic resin. Magnetic recording media such as magnetic tapes and magnetic disks with excellent recording properties are known, and in order to improve the abrasion resistance of their magnetic films, higher fatty acids or their metal salts are deposited on the magnetic film surface by vacuum evaporation. 0 (Japanese Patent Application No. 55-19415 No. 1-51-42279) proposed the production of a wear-resistant magnetic recording material with a thin and strong film.

The present inventor has discovered that the adhesion strength of vapor-deposited particles of the higher fatty acid or its metal salt is subtly affected by the surface condition of the magnetic film, and in particular, once exposed to the outside air after manufacturing, the surface of the magnetic film becomes moisture %. Even if higher fatty acids or their metal salts are vacuum-deposited on 1-1 with 1% dust and other contaminants attached, the adhesion deteriorates in that area and is easily peeled off as a whole. It is recognized that a wear-resistant magnetic recording material with weak, in other words, poor abrasion resistance can be obtained. This provides a method for obtaining an improved magnetic recording material S*, and prior to vacuum-depositing higher fatty acids or their metal salts on the magnetic film surface formed on the magnetic recording material substrate surface,
The method is characterized in that the surface of the magnetic film is subjected to ion bombardment treatment.

Furthermore, according to the present invention, there is provided a method for manufacturing a wear-resistant magnetic recording material that further improves the wear resistance of the above-mentioned manufacturing method. The method is characterized in that, prior to vacuum-depositing higher fatty acids or metal salts thereof on the film surface, the magnetic 1!1 surface is subjected to bombardment treatment in an atmosphere containing an oxidizing gas such as oxygen.

Next, a description will be given of an example of a 1:1 film according to the present invention.

By Oo-! An obliquely deposited magnetic film consisting of i0%lIi (
A magnetic tape having a thickness of 2,500 μm) and a saturation magnetization of 10,400 G and a coercive force of 900 μm was prepared. A pair of rolls (2) +2
The magnetic tape was installed for 1 hour (a indicates the magnetic tape).

In the drawings, (3) indicates a drive motor that rotates in forward and reverse directions to drive one of the pulleys (2) via a belt. (4) shows a mesh-like ion bombardment electrode connected to the external DC current It (51), and the electrode (4) is connected to the magnetic team 1.
They are arranged parallel to and opposite to each other below the surface of the magnetic film of No. 1. (6)
shows a gas supply pipe introduced into the lower side of the container (1), and the amount of gas such as oxygen gas or inert gas such as argon can be freely adjusted by the pulp (7) inserted at 11F +6). Then, the gas pressure inside the vacuum container is adjusted appropriately. An evaporation heater (8) is installed directly below the intermediate portion of the horizontal surface portion on which the magnetic tape a is stretched.

The heating II (8) consists of a vertical furnace core cylinder a- whose outer periphery is wrapped with tantalum 11 (9) in a coil shape, and an outer cylinder (2) made of heavy-duty wool or the like wrapped around the outer periphery. The coiled tantalum winding (9) is connected to an external AC power source I,
The heating temperature was controlled by Slidec I. a4 is the cylindrical heating I! #(8) shows a crucible housed in crucible I, and a lubricant aS of a desired type of higher fatty acid or its metal salt is placed in the crucible I.The wire is a thermocouple for measuring the heating temperature of the raw cod. shows. As a result, while measuring the temperature, the slider 0 was operated to adjust the heating temperature appropriately*a? 1 indicates a heater consisting of an infrared temperature heater and a reflector for heating the magnetic film 11 surface of the magnetic tape a, which is provided below the ion bombardment electric fi64); connected to the hoof.

The a field indicates an intervening slideak in the circuit.

(Company) indicates a thermocouple for measuring the temperature of the magnetic film or the back side of the evaporation layer. @Bυ indicates a pair of shielding plates placed on the left and right, leaving a space for evaporation at an appropriate interval in the middle. 0 Next, an example of implementing the method of the present invention using the above-mentioned apparatus will be described.

The inside of the vacuum container (1) is evacuated to below, for example, l .1) maintained at a gas pressure of -1. On the one hand, the drive motor (3) rotates the magnetic tape (2) in one direction to feed one magnetic tape 1 in one direction at a constant speed;
Make sure to wind it around the other side (2). During this time, a voltage of, for example, -5 oov is applied to the ion bombardment electrode (4) by the power source (5), and the magnetic film 1 of the magnetic tape a is heated with, for example, argon gas pumped at a gas pressure of 0.1 seal for 10 minutes. The tape feed speed is such that the surface receives ion bombardment. In this way, dirt such as moisture and dust adhering to the surface of the magnetic film can be removed by ion bombardment*.
The magnetic tape a having the purified magnetic l[b is wound onto the roll (2) on the other side, and the magnetic tape
Get on top. Purify coral with magnetic tape & f if necessary.
The process may be completed by reciprocating between a and rule (2) and (2) at least once.

When the purification process over the entire length of the magnetic tape is completed as described above, the operation of the ion bombarding electrode (4) is stopped and the higher fatty acid or its metal salt aS prepared in the crucible A4 is immediately heated. ! 111 (11 &: The magnetic tape is heated and evaporated, and the magnetic tape is reverberated by the roll (2) on the other side, for example) &tb the drive motor (8
) is reversed and run slowly in the opposite direction to the above at a speed of, for example, 10 Cal/mm, so that the glue on the first side is rolled up into a single layer (2). During this time, the infrared heated acoustic fin is usually used to Preferably, the magnetic film 1rkJ is heated to a temperature of 60° C. or higher, and the higher fatty acid or its metal salt is vapor-deposited on the surface of the heated magnetic film.

Clamp and wind into one roll (2). This vapor deposition operation may also be carried out in at least one round trip by running the magnetic tape in the opposite direction, if necessary.

According to the findings of many experiments, when the surface of a magnetic film made only of magnetic metal particles is oxidized and higher fatty acids or their metal salts are vapor-deposited on the oxidized surface, they adhere even more strongly to the magnetic film. It was found that a wear-resistant deposited film could be obtained. As a means for this, in place of the inert gas in the above embodiment, an oxidizing gas, usually preferably an oxygen gas, is introduced, and if ion bombardment is performed with this oxygen gas, the surface of the magnetic film can be purified. In addition, the surface can be oxidized at the same time, and when the lubricant is vacuum-deposited on the purified and oxidized magnetic film surface in the same way, a magnetic recording material with even more wear resistance can be obtained as shown in the table below. In addition, when the magnetic film is made of an oxide of a magnetic metal, the vacuum-deposited film with good, strong adhesion can be obtained by ion bombardment using an inert gas, even without performing ion bombardment using an oxidizing gas. It will be done. This stronger binding is thought to be due to stronger chemical adsorption of higher fatty acids or salts thereof on the donor surface.

1. As mentioned above, when the material is vacuum-deposited while the magnetic tape is heated to 60 DEG C. or higher, there is an advantage that tackiness due to excessive deposition can be prevented.

Next, magnetic tapes on which a magnetic film was formed by diagonally depositing a ferromagnetic metal on the tape substrate surface were left in the atmosphere for 1 second after manufacture (Samples 1 to A7), and left for 30 days to form a magnetic film of the metal. The oxide layer is formed on the surface of the film (sample A8)
In order to clarify the effect of ion bombardment on ~AtO), magnetic tapes were obtained using different manufacturing methods as shown in Table 1 below, and their abrasion resistance, etc. were measured, and the results were as follows. As is clear from the table above, compared to sample g2.!, 8, which was vapor-deposited without ion bombardment, the original sample A!, 4, 4, which was vapor-deposited after ion bombardment.
7. ? , 10, the still playback life is significantly extended.

In particular, it can be seen that ion bombardment of a single metal magnetic film with 0-gas has a better effect on the still playback life than ion bombardment with non-oxidizing MR gas. (See samples A4 and 7). Another sample! As is clear from comparing and 10, when the magnetic film has a metal oxidized surface, the ion bombardment gas has a 1-sample still playback life of 4 and 7, regardless of the oxidizing gas. I know what I can get.

In this way, according to the electric power invention, when the magnetic film surface formed on the substrate surface is subjected to ion bombardment treatment before vacuum evaporation of higher fatty acids or its metal salts thereon, the magnetic film surface formed on the surface of the base material is treated with ion bombardment, compared to the case where ion bombardment treatment is not performed. However, it has the effect of producing a magnetic recording body that can be deposited extremely firmly and has significantly improved wear resistance.

[Brief explanation of the drawing]

The drawing shows a cut-away side view M of an example of an apparatus for carrying out the method of the invention. M...Vacuum evaporator =-Magnetic tape 1...Magnetic 1 [(1)...Vacuum volume-(2)-...Gastric tape (3)
-... Drive motor (4)... Ion bombardment electrode (5;... Power supply (6)... Gas supply pipe (7)
)...Pulp (8)...Heating for evaporation 11 (1
4)...Crucible 0...Higher fatty acid or its metal salt 2 people 1

Claims (1)

[Scope of Claims] 16 Magnetic recording body substrate surface &: Prior to vacuum-depositing higher fatty acids or metal salts thereof on the shadowed magnetic film surface, 1) Ion bombardment #& ring is performed on the magnetic film surface. and the ephemerality of wear-resistant magnetic recording media. Before vacuum-depositing higher fatty acids or their metal salts on the magnetic film surface formed on the recording medium substrate surface, S the magnetic film surface should be subjected to bombardment treatment in an atmosphere containing an oxidizing gas rumored to be oxygen. A manufacturing method for a distinctive wear-resistant magnetic recording medium.