JPH0721553A - Device for producing lubricative layer of magnetic recording medium - Google Patents

Abstract

PURPOSE:To enhance the running performance of a magnetic recording medium by uniformly sticking a lubricant and to also enhance productivity by forming a lubricative layer in vacuum after the formation of a magnetic layer especially in the case of a metallic thin film type magnetic recording medium. CONSTITUTION:This device consists of a lubricant feeding means consisting of a tank 1, a pipe 2, etc., an atomizing means consisting of an ultrasonic generator 3 an oscillator 4, a horn 5, etc., by which ultrasonic waves are applied to a lubricant fed from the feeding means to atomize the lubricant and a nozzle 6 for blowing the atomized lubricant. A lubricative layer is formed on the magnetic layer of a magnetic recording medium by blowing such a lubricant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a lubricating layer of a magnetic recording medium.

[0002]

2. Description of the Related Art As a conventionally known magnetic recording medium, a so-called coating type magnetic is formed by coating a nonmagnetic support with a magnetic coating material containing a magnetic metal material and a binder as main components. There are recording media and so-called metal thin film type magnetic recording media in which a magnetic metal material is directly attached to a non-magnetic support by a method such as vapor deposition or sputtering to form a magnetic layer.

In the coating type magnetic recording medium, a lubricant is blended in the magnetic paint for the purpose of lowering the friction coefficient between the magnetic recording medium and the head to improve the running property, and the lubricant is retained in the magnetic layer. It takes the form of Further, in the metal thin film type magnetic recording medium, for the purpose of lowering the friction coefficient between the magnetic recording medium and the head to improve the running property and protect the magnetic layer,
A lubricant is applied onto the magnetic layer by a method such as roller transfer, or a nonmagnetic support is impregnated in a lubricant solution to form a lubricant layer (overcoat layer) on the magnetic layer.

However, in the form in which the lubricant is retained in the magnetic layer, there is a limit to uniformly disperse the lubricant in the magnetic layer, and the expected lubrication performance may not be sufficiently exhibited. In addition, it is difficult to obtain a lubricating layer having a more uniform surface state by a method of applying a lubricant on the magnetic layer as in a metal thin film type magnetic recording medium, and sufficient lubricating performance cannot be exhibited. In addition, in order to form a lubricating layer by roller transfer on a metal thin film type magnetic recording medium, it is necessary to wind the non-magnetic support once and then move to a separately provided production line. The sex is very bad.

[0005]

The present inventors have completed the present invention as a result of earnestly researching a method for solving the above problems and producing a magnetic recording medium having excellent lubricating performance. .

That is, the present invention is an apparatus for forming a lubricating layer by spraying a lubricant on the magnetic layer of a magnetic recording medium, and is a device for supplying a lubricant and a lubricant supplied from the supplying device. Provided is an apparatus for producing a lubricating layer of a magnetic recording medium (hereinafter, referred to as a first apparatus), which comprises a means for applying a sound wave to atomize and a nozzle for spraying the atomized lubricant. It is a thing.

Further, the present invention is an apparatus for forming a lubricating layer by spraying a lubricant on the magnetic layer of a magnetic recording medium, wherein the lubricant is supplied to the supplying means and the lubricant supplied from the supplying means. Provided is an apparatus for producing a lubricating layer of a magnetic recording medium (hereinafter, referred to as a second apparatus), which comprises a means for applying an air flow to atomize and a nozzle for spraying the atomized lubricant. It is a thing.

The first apparatus of the present invention is an apparatus for atomizing and spraying a lubricant by ultrasonic waves, and it can be used in air or in vacuum, but is particularly suitable for forming a lubricating layer in vacuum. Used. Further, the second device of the present invention,
This is a device that atomizes and sprays the lubricant by vigorously applying a gas flow of air, nitrogen gas or the like to the lubricant, and is preferably used for forming a lubricating layer in air.

The non-magnetic support includes polyesters such as polyethylene terephthalate and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene; cellulose derivatives such as cellulose triacetate and cellulose diacetate; polycarbonates; polyvinyl chloride; polyimides; aromatic polyamides. Etc. plastic etc. are used. The thickness of these non-magnetic supports is 3
It is about 50 μm.

In each of the devices of the present invention, atomized lubricant is sprayed onto a magnetic layer of a non-magnetic support on which a magnetic layer is formed, which runs on a suitable traveling device such as a cylindrical can. The spray nozzle is installed at such a position.

It is desirable that the fine particles of the lubricant sprayed by using the first apparatus of the present invention are as fine as possible, and the frequency of ultrasonic waves to be applied is determined by the kind and viscosity of the lubricant. Is selected from the range of 20 kHz to 10 MHz. The amount of lubricant sprayed may be appropriately determined in consideration of the application of the magnetic recording medium, the type of lubricant, etc., but the thickness of the formed lubricating layer should be adjusted to be about 10 to 300 Å. Is preferred.

The lubricant used in the first device of the present invention may be a fatty acid type or a fluorine type, but perfluoropolyether is particularly preferable. Perfluoropolyether compounds are often used for metal thin film type magnetic recording media because of their excellent lubrication performance, but their vapor pressure is low and they are weak against heat. Had been formed. However, in the present invention, by using the ultrasonic atomizer, it is possible to atomize the perfluoropolyether lubricant in a vacuum. As the perfluoropolyether, those having a molecular weight of 2000 to 5000 are suitable, and examples thereof include "FOMBLIN Z DIAC" [carboxyl group-modified, Montecatini Co., Ltd.], "FOMBLIN Z DOAC".
A commercially available product under the trade name of "L" [alcohol-modified, manufactured by Montecatini Co., Ltd.] can be used. Since these have a hydroxyl group or a carboxyl group at the terminal, they can enhance the binding between the lubricant and the magnetic layer, and are therefore particularly preferably used in the present invention.

Besides this, a fluorine-based lubricant containing a benzene ring, a double bond, a branched chain, etc. can also be used. Fluorine-based lubricants are particularly preferably used in the present invention because they improve not only durability but also corrosion resistance as compared with fatty acid-based lubricants.

When the lubricant is sprayed, the lubricant is a fluorine-based inert solvent (for example, perfluorocarbon such as "Fluorinert" manufactured by Sumitomo 3M Limited), an aromatic hydrocarbon solvent such as toluene, and an alcohol solvent. 0.001-10% by weight dissolved in an appropriate solvent such as a ketone solvent
It is preferable to use it as a solution of the degree. When using perfluoropolyether as the lubricant, perfluorocarbon can be used as the solvent, and the concentration is 0.0
It is preferably about 01 to 1.0% by weight.

The above-mentioned lubricant can also be used in the second device of the present invention, and in order to make the lubricant fine particles as fine as possible, the flow rate of the air flow, the supply rate of the lubricant, the hole diameter of the nozzle, and the number of nozzles. And so on.

[0016]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Embodiment 1 A first device of the present invention will be described with reference to the drawings.

FIG. 1 is a conceptual view showing an example of the first device of the present invention, and FIG. 2 is a schematic view showing a state in which the first device of the present invention is installed in a vacuum container.

In FIG. 1, the lubricant supplying means comprises a tank 1 and a pipe 2. The means for applying ultrasonic waves to the lubricant to atomize the lubricant is composed of the ultrasonic oscillator 3, the vibrator 4, and the horn 5. Further, in FIG. 1, 6 is a nozzle for spraying a lubricant atomized by ultrasonic waves, and 10 is a can for carrying a non-magnetic support. The configuration of each means is not limited to these.

The ultrasonic wave generated by the ultrasonic oscillator 3 drives the vibrator 4, and the ultrasonic vibration is magnified by the horn 5. The ultrasonic vibration of the horn 5 is applied to the lubricant supplied from the pipe to atomize the lubricant, and the lubricant is sprayed by the nozzle.

In FIG. 2, reference numeral 7 denotes a vacuum container, the inside of which is maintained at a vacuum degree of about 10 ^-2 to 10 ^-7 Torr by a vacuum pump (not shown). Reference numeral 8 is a schematic view of the first device of the present invention, which is installed inside the vacuum container 7 in this example. 9 is a spray nozzle. A can 10 conveys the non-magnetic support 11 having a magnetic layer formed thereon, and is preferably heated to 40 to 120 ° C. 12 and 13 are feed rolls. In this example, the spray nozzle is installed at a position where the lubricant is sprayed at a right angle to the can.

In the first apparatus, it is possible to form the magnetic layer on the non-magnetic support by vapor deposition in a vacuum and subsequently form the lubricating layer in the vacuum container. Therefore, it is very productive.

Embodiment 2 Next, another embodiment of the first device of the present invention will be described with reference to the drawings.

FIG. 3 is a schematic view showing a state in which the first device 8'of the present invention is installed in a vacuum container. In this example, the spray nozzle 6'is arranged on the left side of the drawing with respect to the can 10 'so that the lubricant is sprayed obliquely to the plane of the magnetic layer. By disposing the spray nozzle in this manner, the voids between the magnetic powder and the binder in the magnetic layer can be more efficiently filled.

Embodiment 3 Next, a second device of the present invention will be described with reference to the drawings.

FIG. 4 is a schematic view showing a state in which the second device of the present invention is installed in the container. In FIG. 3, 14 is a tank which is a means for supplying a lubricant, 15 is a pipe which is a means for supplying an air flow such as air, and 16 is a spray nozzle in which the tank 14 and the pipe 17 are connected. Also, the lubricant supply means and the air flow supply means are not limited to this.

In this example, after forming the magnetic layer on the non-magnetic support by vapor deposition in a vacuum, the lubricating layer is formed in a container (in air) which is not particularly depressurized.

Also when the lubricating layer is formed by the second apparatus of the present invention, the kind of the lubricant used, the thickness of the lubricating layer, etc. are the same as in Example 1, and the gas introduction speed, the nozzle hole diameter, etc. are appropriately set. Should be decided.

[0029]

According to the lubricating layer manufacturing apparatus of the present invention, the adhesion of the lubricant becomes more uniform than in the conventional case, a lubricating layer having a better surface condition is formed, and the running property of the magnetic recording medium is improved. . Further, in the metal thin film type magnetic recording medium, the lubrication layer can be formed continuously with the magnetic layer forming line, so that the productivity is increased. Particularly, in a device that atomizes the lubricant by ultrasonic waves, the lubricant can be sprayed in a vacuum, so that it is possible to prevent dust from adhering to the non-magnetic support.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a first device of the present invention that sprays a lubricant by ultrasonic waves.

FIG. 2 is a schematic view showing a state in which the first device of the present invention is arranged in a vacuum container.

FIG. 3 is a schematic diagram showing another embodiment of the first device of the present invention.

FIG. 4 is a schematic view showing a state in which a second device of the present invention is arranged in a container.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tank 2 ... Tube 3 ... Ultrasonic oscillator 4 ... Oscillator 5 ... Horn 6 ... Spraying nozzle 7 ... Vacuum container 8 ... 1st apparatus of this invention 9 ... Nozzle 10 ... Can 11 ... Non magnetic layer formed Magnetic support 12 ... Feed roll 13 ... Feed roll 14 ... Tank 15 ... Air flow introduction pipe 16 ... Nozzle 17 ... Pipe

Claims (2)

[Claims] 1. A device for forming a lubricating layer by spraying a lubricant on a magnetic layer of a magnetic recording medium, wherein a lubricant supplying means and ultrasonic waves are applied to the lubricant supplied from the supplying means. And a device for atomizing the atomized lubricant, and a nozzle for spraying the atomized lubricant. 2. A device for forming a lubricant layer by spraying a lubricant on a magnetic layer of a magnetic recording medium, wherein a lubricant supply means and an air stream is applied to the lubricant supplied from the supply means. An apparatus for producing a lubricating layer of a magnetic recording medium, comprising: a means for atomizing the lubricant and a nozzle for spraying the atomized lubricant.