JPS5984325A - Magnetic head of vertical magnetic recording system - Google Patents

Abstract

PURPOSE:To maintain lubricity for a long time without using any lubricant so that a recording medium is not damaged and to reduce the wear of the medium, by using a carbon material or a composite material of a carbon material and thermosetting resin for the supporting body of a magnetic head. CONSTITUTION:A glassy carbon having characteristics of 1.49 apparent specific gravity, 112 Shore hardness, and 3kcal/mhr deg.C coefficient of thermal conductivity is cut to have the dimensions (in mm.) shown by the diagram and one surface A which contacts with a recording medium is finished to have a mirror surface. Thus a magnetic head supporting body 7 is manufactured. It is also possible to use a composite material prepared by compression moulding a 70vol% phenolic glassy carbon fiber and 30vol% general purpose resol resin for laminating for this purpose. When such a magnetic head supporting body is used, the lubricity can be maintained for a long time without using any lubricant and the surface of a recording medium is not damaged and worn down. Therefore, this magnetic head supporting body is suitable for vertical magnetic recording system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a magnetic head for recording and reading information from and to a magnetic storage component. In particular, the present invention relates to a magnetic head used in a perpendicular magnetic recording method for recording on a planar magnetic recording medium having an axis of easy magnetization perpendicular to the plane using a perpendicular axis component magnetic field.

[Description of prior art]

Currently considered magnetic recording methods include the longitudinal magnetic recording method and the above-mentioned perpendicular magnetic recording method.

Among them, the longitudinal magnetic recording method has an axis of easy magnetization shown by a solid arrow in the traveling direction of the recording medium l (broken arrow), as shown in FIG. 1, and is currently widely used. However, it has been theoretically established that this method has a limit to increasing the recording density (Iwasaki, IEICE, Magnetic Recording Research Material MR72-7, 1972, 6, and S. Iwasaki, & K, Taka-mura,
IEEE Tras, on Magn, M to G-
11', 5. 1173-1175.1980)
.

In other words, in the longitudinal magnetic recording method, as recording density increases, a rotating magnetic mode 2 based on a demagnetizing field occurs in the recording medium 1 as shown by the arrow in FIG. 2, and when this rotating magnetic mode approaches, , it became impossible to identify the direction of rotation,
Magnetic recording and reproduction become impossible.

On the other hand, in the perpendicular magnetic recording method, as shown in Figure 3, parallel magnetism is applied with a different direction for each half-wavelength of the signal, so an attractive force is exerted between adjacent residual borides in a stable state. There is no effect of demagnetizing field, which is a problem with longitudinal magnetic recording, and as a result, sharp magnetic reversals occur. This magnetic reversal is maintained even when the recording density is increased, so the perpendicular magnetic recording method is a rational method that uses the attractive force of the magnet, and is a feature that can achieve high density magnetic recording. There is.

FIG. 4 shows the basic structure of a magnetic head used in the perpendicular magnetic recording system. Does a conventional magnetic head not make contact with the main pole head 3 and the recording medium l, which contact the surface of the recording medium 1 perpendicularly? It is composed of an ili assistant research pole head 4.

The main pole head 3 is a soft magnetic thin film having a thickness of 1 μm or less, and is protected by being oil-tightly covered by a support 5. 6 is an electric signal terminal.

Conventionally, attempts have been made to use a thermosetting resin such as epoxy resin or a thermoplastic resin such as methyl methacrylate resin for the support 5 that protects this soft magnetic thin film. Commonly used Co-C
When the sputtering film moves in contact with the resin in the direction shown by the arrow in Figure 4, the hardness of the resin is not high, so the resin wears out and has a short life as a support. .

To overcome this drawback, alumina-based ceramics with high hardness are used for the support, but in this case, both the recording medium and the support have high hardness, so it is necessary to make these materials slide smoothly. Therefore, it is essential to use a lubricant.

Examples of this lubricant include fluorine thread compounds (for example, Krytox (trade name, manufactured by DuPont, USA)) and amide compounds, which are applied to the support during sliding. The use of these lubricants improves the lubricity between the Co-Cr sputtered film and the alumina ceramics, but it has the disadvantage that it is difficult to maintain the lubricating effect for a long time due to volatilization of the lubricant. .

[Purpose of the invention]

The present invention solves the above-mentioned drawbacks, and maintains lubricity for a long time without using a lubricant between the support of the main pole head and a highly hard recording medium, and does not damage the surface of the recording medium. It is an object of the present invention to provide a perpendicular magnetic recording type magnetic head in which the support itself has less wear.

[Features of the invention]

A feature of the first invention is that the material of the support is a perpendicular magnetic recording magnetic head mainly made of a carbon material, and a feature of the second invention is that the material of the support is the above-mentioned carbon material and a thermosetting magnetic head. It is a resin composite material.

To further explain the present invention, +a1 Examples of carbon materials used in the present invention include polyacrylonitrile carbon materials, cellulose carbon materials, rayon carbon materials, pinch yarn carbon + A material, and ribinated polyvinyl alcohol carbon materials. , phenolic carbon materials, graphite, carbon blanks, coke, pinch, etc.

The above-mentioned carbon blank is a material that has an appropriate anti-friction property so that when the Go-Cr sputtered film, which is a recording medium, slides, the carbon material itself wears out first before the Go-Cr sputtered film is damaged. Therefore, glassy carbon in an amorphous state is preferable, and crystalline carbon may also be used.

Further, the above-mentioned carbon material is composed of an aggregate of carbon materials in various forms such as fibrous, particulate, or lump-like. Various widely known molding methods such as compression molding and embossing molding can be used to manufacture the aggregate.

(b) Examples of the thermosetting resin used in the present invention include phenol resin, epoxy resin, polyester resin, furan resin, urea resin, melamine, and resin.

When these thermosetting resins are combined with the carbon material, the thermosetting resin acts as a binder that binds the carbon materials together, creating a sturdy support that is strong against mechanical damage such as impact. Obtainable. However, if a large amount of thermosetting resin is composited with carbon material, it will become a support that is subject to a lot of wear compared to conventional materials. That's good.

(c) In addition, the soft magnetic thin film phase that forms the main magnetic pole head of the perpendicular magnetic recording method of the present invention has high magnetic permeability and maximum magnetic flux density, and has an extremely small coercive force as shown in Table 1. material is selected.

These soft magnetic thin film phases are manufactured by a sputtering method or an ultra-quenching method.

(Hereinafter, the margin of this page) Table 1 [Effects of the invention] As described above, according to the present invention, the conventional material has higher hardness than the support of thermosetting resin or thermoplastic resin, and The material is a carbon material or a composite material of a carbon material and a thermosetting resin, which has lower hardness than the alumina ceramic support and has an appropriate friction reduction property when moving in contact with the Co-Cr sputtering film that is the recording medium. By using an excellent perpendicular magnetic field, it is possible to maintain lubricity with the recording medium for a long time without using a lubricant, and it does not damage the surface of the recording medium, and the support itself has less wear. A recording type magnetic head can be obtained.

In particular, by using a composite material of a carbon material and a thermosetting resin, there is an advantage that the density of the support is increased and the mechanical strength of the support is increased.

Furthermore, due to the conductivity of the carbon material, static electricity is not generated and dust does not adhere to the support and the recording medium.

[Explanation based on examples]

Hereinafter, the present invention will be explained in more detail with reference to examples in order to show specific aspects of the magnetism and node of the perpendicular magnetic recording method of the present invention, but the examples shown below are merely examples, and
This does not limit the technical scope of the present invention.

(Example I) A glassy carbon +A material having the characteristics of apparent &J specific gravity 1.49, Shore hardness 112, and thermal conductivity 3 Kcal/mhr"C was prepared in the shape and dimensions shown in FIG. 5 (unit: sn ), and the sliding surface A that contacts the recording medium is roughly polished and then gradually finely polished, and finally emery paper #1
5000 to produce a nearly square prism model head 7.

(Example ■) Apparent specific gravity 1.45, Shore hardness 78, thermal conductivity 15
A model head having the same shape and dimensions was produced in the same manner as in Example ① using a glassy carbon material having a characteristic of Kcal/rn hr°C.

(Example ■) Phenolic glassy carbon fiber (manufactured by Nippon Kynor@,
A composite glass-like carbon material was obtained by compression molding 70% by volume of KYNOL (registered trademark) and 30% by volume of TIL resin for lamination. Using this composite glassy carbon material, a model head having the same shape and dimensions was produced in the same manner as in Example (2).

(Example ■) A mixture of graphite and phenol resin (volume mixing ratio 60:4
0) was compression molded, then fired, and then graphitized.
A carbon material having an apparent specific gravity of 1.7 and Shore hardness of 85 was used. Using this carbon material, a model head having the same shape and dimensions was produced in the same manner as in Example (2).

(Example ■) A carbon material was obtained by molding a carbon blank, coke, and pinch in a mixing ratio (volume mixing ratio: 60:10:30) and firing at about 1000°C. Using this carbon material, a model head having the same shape and dimensions was produced in the same manner as in Example I.

(Comparative Example ■) A model head having the same shape and dimensions as in Example I was prepared using alumina ceramics (manufactured by Nippon Electric Glass OL, trade name: Neoceram) in the same manner as in Example I.

(Comparative Example ■) A model head having the same shape and size was prepared in the same manner as in Example I using a commercially available general-purpose acrylic resin.

(Comparative Example ■) A model head having the same shape and dimensions as in Example I was prepared using a commercially available general-purpose Teflon resin.
(Test method) The dynamic friction characteristics of the model heads of Examples I to ■ and Comparative Examples I to 1 and the Go-Cr sputtered film that is the recording medium were measured using a friction test device, and the sliding surface and Co
The state of the -Cr sputtered film was observed with the naked eye. The results are shown in Table 2. The friction test device used in the measurements is a device that can measure dynamic friction characteristics under conditions close to actual usage conditions, as described in Japanese Patent Laid-Open No. 55-128142.

In addition, "durability" in the table refers to the sliding surface of the magnetic head and
- It means the judgment result when both sides of the Cr sputtering film surface were comprehensively observed.

(hereinafter referred to as the margin of this page) Table 2 (hereinafter referred to as the margin of this page) (Example ■) The glassy carbon material used in Example ■ was cut into the shape and dimensions (unit: fin) shown in Figure 6, and a support was prepared. I got 8. As shown by hatching in FIG. 6, a soft magnetic thin film 9 (0.1 pm thick, 2 fin wide
-Mo permalloy film) is deposited by sputtering method. On the support 8 on which the soft magnetic thin film 9 was deposited,
A support 8 of the same shape on which the soft magnetic thin film 9 is not deposited
These are overlapped and bonded together using an epoxy adhesive (trade name: Araldite, manufactured by Chipa Geigy). Next, the side in contact with the recording medium was ground down and the tip was sharpened to form a main pole head body 10 having the shape shown in FIG. 7.

Furthermore, the sharp tip was polished using #4000 and #6000 lapping tape (manufactured by Nippon Micro Coating 0 Kiku) to smooth the tip surface and obtain a main pole head.

Using this main pole head and a magnetic tape formed of a Go-Cr sputtering film having a recording capacity of 30,000 bits/inch, the reproduction voltage drop and the envelope 1-waveform were measured. Furthermore, the conditions of the Go--Cr sputtered film surface and the main magnetic pole head surface were observed with the naked eye 5 hours after the start of the measurement. The results are shown in Table 3.

(Example ■) The carbon material used in Example ■ was cut into the shape and dimensions shown in FIG. I did it. The results are shown in Table 3.

(Comparative Example ■) The alumina ceramic used in Comparative Example I was cut into the shape and dimensions shown in Figure 6, and a main pole head was obtained in the same manner as in Example ■. Observations were made. The results are shown in Table 3.

(Comparative Example ■) A lubricant (stearamide) was applied to the surface of the main pole head obtained in Comparative Example ■, and it was lightly wiped off with a cloth, and the same measurements and observations as in Example ■ were performed.

The results are shown in Table 3.

Table 3 (Test Results) As is clear from Tables 2 and 3, the magnetic throat of the perpendicular magnetic recording system of the present invention has excellent lubricity with the magnetic recording medium, and the head sliding surface and It can be seen that the recording medium is not damaged and the electrical characteristics during reproduction are also excellent.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the orientation direction of the axis of easy magnetization in a recording medium using a longitudinal magnetic recording method. FIG. 2 is a cross-sectional view of the recording medium shown in FIG. 1, showing a rotating magnetic mode. FIG. 3 is a perspective view showing the orientation direction of the easy axis of magnetization in a perpendicular magnetic recording recording medium. FIG. 4 is a perspective view showing the basic structure of a perpendicular magnetic recording type magnetic head. FIG. 5 is an external perspective view of a model head made of the material used in the magnetic head according to the embodiment of the present invention. FIG. 6 is a $H1 perspective view of the support and soft magnetic i-film used in the magnetic head according to the embodiment of the present invention. FIG. 7 is an external perspective view of a magnetic head according to an embodiment of the present invention. 1... Recording medium, 2... Rotating magnetic mode, 3...
Main magnetic pole head, 4... Auxiliary magnetic pole head, 5.8...
Support body, 6... Electric signal terminal, 7... Model head, 9... Soft magnetic thin film, 10... Main magnetic pole head body. 3J'-Itodawokoichi Doji Notification: January 11, 1980 Kazuo Wakasugi, Director General of the Patent Office 1. Indication of the case 1988 Patent Application No. 194013 2. Name of the invention Perpendicular magnetic recording system Magnetic head 3, relationship with the case of the person making the correction Patent applicant address: IO, 14-chome, Kayaba-cho, Nihonbashi, Chuo-ku, Tokyo
Name (091) Kao Soap Co., Ltd. Representative: Yoshibe Maruta 4, Agent Address: 18-1, 2-26 Kita-2-Chome, Sekimachi, Nerima-ku, Tokyo
1. Name Patent Attorney (7823) Ilit Naoken 1, 1,:. , 4 ・)) 5. Date of amendment order (voluntary amendment) 6. Number of inventions increased by amendment None 7. "Claims" column 8 of the specification to be amended 8. Contents of the amendment Scope of claims Correct as shown in the attached sheet. [Attachment] [Claims] (1) Used in a perpendicular magnetic recording method in which a planar magnetic recording medium having an axis of easy magnetization perpendicular to the surface is recorded with a vertical axis component magnetic field, and having high magnetic permeability and high saturation magnetic flux. A perpendicular magnetic recording magnetic head comprising a soft magnetic thin film material having density and a support for supporting the thin film material, wherein the support is made of a carbon material. head. (2) A perpendicular magnetic recording type magnetic head according to claim (1), wherein the carbon material is glassy carbon. (3) A magnetic head of perpendicular magnetic recording method according to claim 11, wherein the carbon material is crystalline carbon. (4) A planar magnetic recording medium having an axis of easy magnetization perpendicular to the plane is A soft magnetic material with high magnetic permeability and high saturation magnetic flux density that is used in perpendicular magnetic recording methods that record with an axial component magnetic field.
A perpendicular magnetic recording magnetic head comprising a film material and a support for supporting the thin film phase, the support being made of a composite material containing a carbon material and a thermosetting resin. A magnetic head of a magnetic recording system. A magnetic head of a perpendicular magnetic recording system according to claim 1, wherein the carbon material is glassy carbon. Claim 4, wherein the carbon material is crystalline carbon. A magnetic head of the perpendicular magnetic recording system described in Proceedings 1it and 2tF: 1980, 4 No. 311, Commissioner of the Japan Patent Office, Kazuo Wakasugi, 1, Indication of the case, 1988 Patent Application No. 1940131 + 2, Name of the invention, Perpendicular magnetism. Relationship between the magnetic head 3 of the recording method and the case of the person making the correction Patent applicant address: 14-10, Kayabacho-Chome, Nihonbashi, Chuo-ku, Tokyo
Title (091) Kao Soap Co., Ltd. Representative 91
1. Yoshibe 4. Agent 5. Date of amendment order (voluntary amendment) 6. Number of inventions increased by amendment None. 8. Contents of amendment (1) Specification store page 8 line 15 Between the beginning of line 16 and the beginning of line 16, ``(d) In addition,'' in the second explanation, a glassy carbon material or a composite material of a glassy carbonaceous material and a thermosetting resin is transferred to the magnetic field of the perpendicular magnetic recording system. Although these materials have been described as a support for magnetic heads, they can also be applied to members with which magnetic recording media come into sliding contact.

Claims (5)

[Claims] (1) A soft magnetic thin film material with high permeability and high saturation magnetic flux density that is used in perpendicular magnetic recording methods that record on a planar magnetic recording medium with an axis of easy magnetization perpendicular to the plane using a perpendicular axis component magnetic field. A perpendicular magnetic recording magnetic head comprising: a support for supporting the thin film material, wherein the support is made of a carbon material. (2) A perpendicular magnetic recording type magnetic head according to claim (1), wherein the carbon material is glassy carbon. (3) A perpendicular magnetic recording magnetic head according to claim 1, wherein the carbon material is crystalline carbon. (4) A soft magnetic thin film material with high magnetic permeability and high saturation magnetic flux density, which is used in perpendicular magnetic recording method in which a planar magnetic recording medium with an axis of easy magnetization perpendicular to the plane is recorded with a perpendicular axis component magnetic field. , a perpendicular magnetic recording magnetic head comprising a support for supporting the thin film material, wherein the support is made of a composite material containing a carbon material and a thermosetting resin. head. (4) A perpendicular magnetic recording type magnetic head according to claim (3), wherein the carbon material is glassy carbon. (5) A perpendicular magnetic recording magnetic head according to claim (3), wherein the carbon material is crystalline carbon.