JP3206322B2 - Magnetic head and magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-capacity magnetic recording / reproducing apparatus excellent in high-density recording / reproducing characteristics and a ring-type magnetic head mounted on the apparatus.

[0002]

2. Description of the Related Art At present, magnetic recording / reproducing apparatuses tend to have a high recording density in order to realize a small size and a large capacity.
To cope with this, in the field of magnetic recording media and magnetic heads, much research and development has been promoted to improve recording / reproducing characteristics in a high recording density region.

In order to improve the recording / reproducing resolution in a high recording density region of a magnetic recording medium, it is necessary to increase the residual magnetization, increase the coercive force corresponding to the magnitude of the residual magnetization, and reduce the thickness of the magnetic layer. is there. In particular, thin-film magnetic recording media manufactured by vacuum deposition, sputtering, ion plating, etc., have attracted attention as exceeding the limits of conventional coating-type magnetic recording media from the above viewpoints.

On the other hand, in a magnetic head, in order to improve a recording capability in response to a high coercive force of a magnetic recording medium,
Development of a soft magnetic material having a high saturation magnetic flux density has been advanced, and a ring-type magnetic head using a soft magnetic material having a saturation magnetic flux density exceeding 1.5 T has already been put into practical use.

As a typical example of a thin film type magnetic recording medium, Hi
There is a vapor deposition tape that has been put to practical use for an 8 system VTR.
The feature of this magnetic recording medium is that, unlike the conventional longitudinal recording medium, the axis of easy magnetization is inclined with respect to the film normal of the magnetic layer. That is, the axis of easy magnetization is not in the film plane or in the normal direction of the film, but in a direction oblique to the film normal in the normal plane including the longitudinal direction of the tape. For example, in a commercially available evaporated tape for Hi8 type VTR, the axis of easy magnetization is inclined by about 70 ° from the film normal in the plane including the longitudinal direction of the tape. The magnetization recorded by the ring type magnetic head remains in the direction of the easy axis of magnetization that is obliquely inclined, and forms a magnetization mode different from that of the conventional longitudinal recording. By forming such an oblique magnetization mode,
The high recording density characteristic is remarkably improved as compared with the longitudinal recording medium.

As the superiority of the oblique magnetization mode over the longitudinal magnetization mode becomes clear, in recent years, attempts have been made to improve the high recording density characteristics by realizing the oblique magnetization mode even in a conventional coating type medium. .

In order to produce the above-described evaporation tape having oblique anisotropy with high productivity, a continuous polymer film using a cylindrical roller system is used to move a long polymer substrate while moving it. What is necessary is just to vapor-deposit a magnetic layer continuously on it. An example of the manufacturing method will be described below with reference to FIG. FIG. 13 shows an example of the internal structure of a vacuum evaporation apparatus for producing an evaporation tape. While the substrate 21 made of a long polymer material unwound from the supply roll 29 travels in the direction of the arrow 28 along the cylindrical can 27, the evaporated atoms 34 evaporated from the evaporation source 33 adhere to the substrate 21. Thus, a magnetic layer is formed. The evaporation source 33 includes, for example, Co and Ni.
In the case of manufacturing a high-band 8 mm VTR vapor deposition tape containing P and O as main components, an alloy of Co and Ni is filled. In addition, as the vapor deposition method, there are methods such as resistance heating and induction heating. In particular, electron beam vapor deposition is suitable for evaporating a high melting point metal such as Co at a high evaporation rate. 31
A and 31B are shielding plates provided to prevent unnecessary evaporated atoms from adhering to the substrate. This shield plate, the incident angle to the substrate of the evaporated atoms is, with respect to the substrate normal, is set from the value phi _i in film formation start portion in a region between values phi _f in film forming finished part. The direction of inclination of the axis of easy magnetization of the deposited magnetic layer is controlled mainly by the setting of φ _i and φ _f . Conventionally, when manufacturing a vapor deposition tape or the like for a Hi8 VTR, it is considered that the incident angle of the evaporated atoms at the film formation start portion to the substrate is preferably 90 ° with respect to the substrate normal. The shielding plate 31A is not used. Reference numeral 32 denotes an oxygen inlet for introducing oxygen into the vacuum chamber during vapor deposition. Reference numeral 30 denotes a take-up roll that takes up the substrate 21 on which the magnetic layer is formed.

[0008]

In the future, magnetic recording / reproducing apparatuses are becoming smaller and larger in capacity. Therefore, in a magnetic recording / reproducing system using a combination of a magnetic head and a magnetic recording medium, it is required to achieve higher S / N than ever before, especially higher S / N in a high linear recording density region.

[0009]

In order to solve the above-mentioned problems, the present invention has improved the magnetic recording / reproducing performance of the obliquely anisotropic magnetic recording medium by improving the configuration of the ring type magnetic head and the magnetic recording / reproducing apparatus. And is realized by the following configuration.

As a first configuration of the ring type magnetic head, a first magnetic core half and a second magnetic core half formed by applying a metal soft magnetic film on a ferromagnetic ferrite surface are opposed to each other. A metal-in-gap type ring-type magnetic head constituting a magnetic circuit having a gap, wherein the average thickness of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half is 1.5 μm or more; In addition, the average thickness of the metal soft magnetic film deposited on the gap forming surface of the second magnetic core half is equal to the average thickness of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half. More preferably, the saturation magnetic flux density of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half has a saturation magnetic flux density of the metal deposited on the gap forming surface of the second magnetic core half. Smaller than the saturation magnetic flux density of the soft magnetic film. And butterflies.

[0011]

[0012] As a further second configuration, a ring-type magnetic head for a magnetic circuit having a gap opposition the first magnetic core half and the second magnetic core halves made of a ferromagnetic material, a first The magnetic material forming the gap forming surface of the magnetic core half and the vicinity thereof and the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof are composed of a plurality of the same elements as main components. Alternatively, the magnetic material forming the gap forming surface of the first magnetic core half and the vicinity thereof includes B and C as elements constituting the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof. , N, and O, and the saturation magnetic flux density of the magnetic material forming the gap forming surface of the first magnetic core half and its vicinity is the second magnetic core. Wherein the gap forming surface of core half and smaller than the saturation magnetic flux density of the magnetic material constituting the neighborhood.

The structure of the magnetic recording / reproducing apparatus is such that a magnetic recording medium having an easy axis of magnetization inclined with respect to the film normal of the magnetic layer is provided with a ring-type magnetic head having the above-described first and second structures. What is claimed is: 1. A magnetic recording / reproducing apparatus for recording a signal using at least one selected magnetic head, wherein a magnetic head is provided in a plane of a magnetic layer of a magnetic recording medium including a relative movement direction of the magnetic head and the magnetic recording medium in a recording process. The magnetic field near the leading edge of the recording medium and the axis of easy magnetization of the magnetic recording medium are inclined to the same side with respect to the film normal of the magnetic layer of the magnetic recording medium, and the relative movement of the magnetic head and the magnetic recording medium during the recording process In the direction, the first magnetic core half of the magnetic head has a leading side and the second magnetic core half has a trailing side.

[0014]

Generally, in the process of recording a magnetic recording medium having a high coercive force using a ring type magnetic head, the head is required to have a recording magnetic field large enough to sufficiently reverse the magnetization of the high coercive force medium. That is, the higher the saturation magnetic flux density of the soft magnetic material constituting the head is, the higher the reproduction output can be obtained by the improvement of the magnetization reversal ability, but at the time when the sufficient magnetization reversal ability is realized with respect to the coercive force of the medium. It is considered that even if the saturation magnetic flux density of the head material is further increased, a remarkable improvement in reproduction output can no longer be expected.

On the other hand, the present inventors have developed a ring type magnetic head in which a recording magnetic field is asymmetric with respect to a center line of a head gap and has a steeper gradient on a trailing edge side in recording / reproducing of an obliquely anisotropic magnetic recording medium. The recording magnetic field near the leading edge of the ring-type magnetic head and the axis of easy magnetization of the medium within the normal of the medium magnetic layer including the relative movement direction of the ring-type magnetic head and the obliquely anisotropic magnetic recording medium during recording Are inclined to the same side with respect to the film normal of the medium magnetic layer, and it has been found that the recording output is remarkably improved as compared with the related art by recording with the configuration shown in FIG. FIG. 12 shows only the vicinity of the leading edge 15 and the trailing edge 16 via the gap 6 in the ring type magnetic head.

When the head has a saturation magnetic flux density enough to sufficiently reverse the magnetization of the magnetic recording medium, the amount of magnetization remaining in the transition region 26 can be sufficiently saturated by the conventional head. . On the other hand, the magnetization transition region 2
In No. 5, behavior different from the conventional one is seen in the configuration of FIG. In the configuration of FIG. 12, the rate of decrease in the component of the recording magnetic field 18 in the direction of the axis of easy magnetization of the medium from near the gap center line 17 to the trailing edge side is steep. According to such a recording magnetic field 18, the recording magnetization by the recording magnetic field on the leading side is quickly demagnetized or reversed by the recording magnetic field on the trailing side which is steeper than the conventional head. Therefore, the magnetic layer 20
, A narrower magnetic transition region 25 is realized, and it is considered that the reproduction output particularly in the high linear recording density region is increased as compared with the conventional configuration.

In order to obtain the above-described recording mechanism, the ring-type magnetic head is required to be positioned within the plane of the medium magnetic layer including the relative movement direction of the ring-type magnetic head and the obliquely anisotropic magnetic recording medium during recording. It is necessary that the recording magnetic field near the leading edge and the axis of easy magnetization of the medium are inclined to the same side with respect to the film normal of the medium magnetic layer. In other words, it is necessary that the direction of the recording magnetic field near the leading edge is close to the easy axis direction of the medium and conversely, the direction of the recording magnetic field near the trailing edge is close to the hard axis direction of the medium. It is not necessary to exactly match the inclination direction of the recording magnetic field and the inclination direction of the easy axis of the obliquely anisotropic medium. In the current VTR, the rotary head scans slightly obliquely with respect to the length direction of the magnetic tape. For example, in the case of the Hi8 type VTR, an angle of about 5 ° is formed with respect to the length direction of the magnetic tape. The head is scanned in the direction. However, even in a configuration like the VTR, the inclination direction of the recording magnetic field near the leading edge is close to the inclination direction of the easy axis of the medium, and conversely, the inclination direction of the recording magnetic field near the trailing edge is difficult for the medium. If the configuration is close to the axial direction, the recording mechanism of the present invention can be sufficiently realized and the recording / reproducing characteristics can be improved.

On the other hand, contrary to the structure of the present invention, the trailing of the ring-type magnetic head is performed within the plane of the medium magnetic layer including the relative movement direction of the ring-type magnetic head and the obliquely anisotropic magnetic recording medium during recording. When the recording magnetic field near the edge and the axis of easy magnetization of the medium are inclined to the same side with respect to the film normal of the medium magnetic layer, the above-described recording mechanism of the present invention can be realized. It is not possible. In this case, since the inclination direction of the recording magnetic field on the trailing side is close to the easy axis direction of the medium, the shorter the recording wavelength, the more easily the recording demagnetization becomes, as in the case of the conventional longitudinal recording. No linear recording density characteristics can be obtained.

According to the present invention, a ring-type magnetic head having a recording magnetic field that is asymmetrical with respect to the center line of the head gap and has a steeper gradient on the trailing edge side is provided by one of the following three components. Is achieved.

The first element is that a first magnetic core half and a second magnetic core half formed by coating a metal soft magnetic film on the surface of a ferromagnetic ferrite face each other and have a gap. In a metal-in-gap type (hereinafter, referred to as MIG type) ring type magnetic head constituting a circuit, the average thickness of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half is equal to or smaller than the first thickness. In a head having a configuration smaller than the average thickness of the metal soft magnetic film deposited on the gap forming surface of the second magnetic core half, the first magnetic core half is realized on the leading side.

In this configuration, by making the thickness difference between the metal soft magnetic films of the two magnetic core halves sufficiently large, the portion near the gap in the first magnetic core half on the leading side is more magnetic than the trailing side. It is easy to reach saturation, and a steeper asymmetric magnetic field is obtained on the trailing side with respect to the gap center line.

The second element is a ring-type magnetic head which forms a magnetic circuit having a gap by opposing a first magnetic core half and a second magnetic core half made of a ferromagnetic material. The magnetic flux density of the magnetic material forming the gap forming surface of the magnetic core half and the vicinity thereof is smaller than the saturation magnetic flux density of the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof. This is also realized by making the first magnetic core half on the leading side.

Also in this configuration, by sufficiently increasing the difference between the saturation magnetic flux densities of the metal soft magnetic films of the two magnetic core halves,
The portion near the gap in the first magnetic core half on the leading side is more likely to reach magnetic saturation than on the trailing side, and a steeper asymmetric magnetic field is obtained on the trailing side with respect to the gap center line.

The third element is a ring-type magnetic head which forms a magnetic circuit having a gap by opposing a first magnetic core half and a second magnetic core half made of a ferromagnetic material. In a head having a configuration in which the magnetic path cross-sectional area of the gap forming surface of the magnetic core half is smaller than the magnetic path cross-sectional area of the gap forming surface of the second magnetic core half, the first magnetic core half is connected to the leading side. This is also realized by:

Also in this configuration, the portion near the gap in the first magnetic core half on the leading side is more likely to reach magnetic saturation than on the trailing side, and a steeper asymmetric magnetic field is generated on the trailing side with respect to the gap center line. The effect obtained is recognized.

However, among the three components, the third component has the smallest effect of obtaining a steeper asymmetric magnetic field on the trailing side with respect to the gap center line, and the effect of the present invention is sufficiently obtained alone. It is difficult. For this reason, it is usually preferable to implement the third element at the same time as the second element. Alternatively, if it is a MIG type head, it may be realized simultaneously with the first element.

In the MIG type head, 1
If the second element and the second element are realized at the same time, generally, the effects of the present invention are more remarkably obtained than when each is realized independently, which is more preferable. Furthermore, if the third element is simultaneously realized by incorporating the third element, the effect of the present invention can be more remarkably obtained.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, a ring type magnetic head having the first to third configurations described in the section of the means for solving the problems, and a commercially available VTR were modified to make these ring type magnetic heads. A magnetic recording / reproducing apparatus equipped with a head will be described below. The magnetic recording medium used was an oblique anisotropic evaporation tape manufactured by a continuous evaporation apparatus.

(Example of Configuration of Magnetic Recording Medium) First, a method of manufacturing a magnetic recording medium and magnetic characteristics suitable for the configuration of the present invention will be described with reference to FIG. In this embodiment, FIG.
Using a continuous vapor deposition apparatus shown in FIG. 3, a vapor deposition tape having a magnetic layer containing Co and O as main components whose easy axis of magnetization is inclined with respect to the film normal is prepared and described.

When the magnetic layer is formed, the substrate 21 made of a polymer material is placed along the surface of the cylindrical can 27 by arrows 2.
Run in the direction of 8. As the substrate 21, a polyethylene terephthalate film, a polyethylene naphthalate film, a polyimide film, a polyamide film,
Any of those generally used for magnetic tapes such as a polyetherimide film and a polycarbonate film can be used. In the study in this example, a polyethylene terephthalate film having a thickness of 7 μm was used.

The evaporation source 33 is filled with a metal or alloy material constituting the magnetic layer. Usually, Co—Ni, Co—Cr, Co—
A Co-based alloy such as Ni-Cr or Co-Pt is filled. In the present embodiment, since a magnetic tape having a magnetic layer containing Co and O as main components was studied, the evaporation source 33 was filled with Co. At this time, a magnetic layer containing Co and O as main components is formed by performing reactive deposition while introducing oxygen from the oxygen inlet 32 into the vacuum chamber during the film formation.

Shielding plates 31A and 31B are arranged between the evaporation source 33 and the cylindrical can 27. The evaporated atoms 34 are deposited on the substrate 21 through the openings of the shielding plate.

Φ _i and φ _f are the incident angles of the evaporated atoms to the substrate 21 at the start and end of film formation of the magnetic layer, respectively. Control of the values of φ _i and φ _f is very important in controlling the tilt direction and orientation of the easy axis of the magnetic layer described below.

As shown in FIG. 12, in the magnetic recording medium having an oblique anisotropy used in the structure of the present invention, the angle between the easy axis 22 and the film normal 23 is represented by β. Here, β is a value obtained without correcting the effect of the demagnetizing field in a sample having a sufficiently large area as compared with the thickness of the magnetic layer and a demagnetizing factor in the film normal direction due to the shape being recognized to be approximately 1. I do. In order to sufficiently obtain the effects of the configuration of the present invention, it is preferable that β of the magnetic recording medium used is not less than 50 ° and not more than 85 °, not limited to the vapor-deposited tape manufactured by the above-described manufacturing method. When β is 85 ° or more, the axis of easy magnetization 22
Is too close to the film plane, so that it becomes difficult to form an oblique magnetization mode during recording. That is, as in the conventional longitudinal recording, as the recording wavelength becomes shorter, the recording magnetic field on the trailing side becomes more susceptible to recording demagnetization, and excellent high linear recording density characteristics cannot be obtained. On the other hand, even when β is 50 ° or less, the easy magnetization axis 22 is too close to the film normal, so that it is easily demagnetized by the recording magnetic field on the trailing side, and it is difficult to realize an ideal oblique magnetization mode.

Further, in order to sufficiently obtain the effects of the structure of the present invention, it is necessary that the magnetic recording medium used has high orientation and excellent magnetic properties. In order to obtain the effect of realizing a narrow magnetic transition width by the recording mechanism of the present invention, the resolution of the magnetic recording medium itself that determines the limit of the magnetic transition width must be high. When a magnetic recording medium having insufficient orientation and large anisotropic dispersion is used, the magnetization transition width is limited by the resolution of the medium itself before the effect of the present invention is obtained. On the other hand, the effect of the present invention is more remarkably obtained as a medium having a high orientation and a small anisotropic dispersion is used. In view of the above, according to the study of the present inventors, as the magnetic characteristics of the magnetic recording medium, the coercive force in the easy axis direction is 80 kA / m or more, and the uniaxial anisotropy constant is 10 ⁵ J / m ^3.
It is preferable that it is above. In the vapor deposition tape produced by the production apparatus shown in FIG. 13, from the viewpoint of obtaining an appropriate magnetization easy axis direction β and producing a highly oriented vapor deposition tape with little anisotropic dispersion, φ _i and φ _f It is important to set it properly. In this embodiment, for example, β is about 75 °, the coercive force in the easy axis direction is about 145 kA / m, Anisotropy constant is about 2.8 × 10 ⁵ J / m
A value of ³ has been realized. The saturation magnetization of this vapor deposition tape is about 650 kA / m, and the thickness of the magnetic layer is about 100 nm.

In order to use in the magnetic recording / reproducing apparatus in this embodiment, the vapor-deposited tape manufactured by the above method has a carbon protective film of about 10 nm thick and a lubricant layer of several nm thick on the magnetic film side. A back coat layer having a thickness of 0.5 μm was formed on the back surface. Thereafter, it was cut into an appropriate width and length and inserted into a commercially available cassette for use.

(First Configuration Example of Ring-Type Magnetic Head) Next, a configuration example of the ring-type magnetic head of the present invention will be described. First, as a first configuration, a first magnetic core half and a second magnetic core half formed by coating a metal soft magnetic film on a ferromagnetic ferrite surface are opposed to each other to form a magnetic circuit having a gap. In the MIG type ring type magnetic head, the average thickness of the metal soft magnetic film deposited on the gap forming surface of the second magnetic core half is equal to that of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half. The ring type magnetic head having a thickness larger than the average thickness of the metal soft magnetic film will be described in detail.

FIG. 1 shows an example of the MIG type ring type magnetic head having the above-mentioned first configuration. FIG. 1 (a)
FIG. 1B is a diagram showing a configuration example of a cross section of a core in a gap length direction 7 in a medium sliding surface of a ring type magnetic head. According to the configuration of the present invention, in the recording process, the first magnetic core half is used as the leading side, and the second magnetic core half is used as the trailing side. Here, the first
The thicknesses of the metal soft magnetic films 3a and 3b deposited on the gap forming surfaces of the magnetic core half 1 and the second magnetic core half 2 are as follows.
It shall be measured in the gap length direction 7 of the head, are respectively represented by d _a, d _b in FIG. 1 (b). The average thickness of the metal soft magnetic film deposited on the gap forming face is represented by an average value in the gap width direction 8 of d _a or d _b. As shown in the figure, the average thickness of the metal soft magnetic film deposited on the gap forming surface of the second magnetic core half is different from that of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half. With a configuration larger than the average thickness of the film, a ring-type magnetic head of the present invention is obtained in which the recording magnetic field is asymmetric with respect to the center line of the head gap and has a steeper gradient on the trailing edge side.

In the configuration shown in FIG. 1, the metal soft magnetic film 3a (having a saturation magnetic flux density of _Bsa ) attached to the first magnetic core half, and the metal soft magnetic film 3a attached to the second magnetic core half If the soft magnetic film 3b (saturation magnetic flux density is assumed to be B _sb ) is made of different kinds of magnetic materials and the relationship of B _sb > B _sa is satisfied, the recording magnetic field increases asymmetry, and the magnetic field gradient on the trailing edge side is increased. Is more preferred because of the larger size.

Here, in order to realize a sufficient recording capability on a highly oriented obliquely anisotropic medium having a high coercive force and to exert the effect of the present invention, the recording magnetic field on the leading edge side must be adjusted to the medium. It is necessary to have sufficient magnetization reversal capability. Therefore, when recording is performed on an obliquely anisotropic medium having a high coercive force of 80 kA / m or more in the direction of the easy axis as described above, the recording medium is attached to the first magnetic core half on the leading side. It is preferable that the saturated magnetic flux density B _sa of the metal soft magnetic film 3a thus obtained is at least 0.8T or more. When B _sa is smaller than 0.8 T, the effect of the present invention is hardly obtained because the recording magnetic field on the leading side cannot sufficiently reverse the magnetization of the medium. Alternatively, a very large exciting current is required, which is not preferable in terms of power consumption of the device. Even when B _sa is larger than 0.8T, the smaller the average thickness of the metal soft magnetic film 3a applied to the first magnetic core half, the lower the magnetization reversal ability and the effect of the present invention can be obtained. It becomes difficult. According to the study of the present inventors, in order to obtain a sufficient magnetization reversal ability, the average thickness of the metal soft magnetic film 3a applied to the first magnetic core half should be at least 1.5 μm or more. is necessary.

As a configuration example that is not preferable from the above viewpoint, for example, the following configuration example is given. That is, MI
In the configuration of the G type head, a metal soft magnetic film having a high saturation magnetic flux density is formed only on the gap forming surface of the second magnetic core half, and the gap forming surface of the second magnetic core half remains ferrite. With this configuration, a ring magnetic head having a recording magnetic field that is asymmetric with respect to the center line of the head gap and that has a steeper gradient on the trailing edge side can be most simply realized. However, in this case, since the saturation magnetic flux density of the ferrite constituting the leading edge is as small as about 0.5T, the magnetization reversing ability due to the leading side magnetic field is lacking, and the effect of the present invention is hardly obtained from the above viewpoint.

In order to realize the recording mechanism of the present invention, the recording magnetic field becomes asymmetric with respect to the gap center line,
It is necessary to have a steeper slope on the trailing side. From this viewpoint, the saturation magnetic flux density B _sb of the metal soft magnetic film 3b adhered to the second magnetic core half is approximately equal to the saturation magnetic flux density B _sa of the metal soft magnetic film 3a of the first magnetic core half. In the case of (1), in order to realize the above-described asymmetric recording magnetic field and sufficiently obtain the effect of the present invention, the metal soft magnetic film 3b adhered to the gap forming surface of the second magnetic core half on the trailing side is required. Needs to be larger than twice the average thickness of the metal soft magnetic film 3a deposited on the gap forming surface of the first magnetic core half. When the average thickness of the metal soft magnetic film 3b is less than twice the average thickness of the metal soft magnetic film 3a, the asymmetry of the recording magnetic field becomes insufficient, and the effect of the present invention is hardly obtained. As described above, since the average thickness of the metal soft magnetic film 3a is required to be 1.5 μm or more, the metal soft magnetic film 3b
Must have an average film thickness of at least 3 μm. On the other hand, if the average thickness of the metal soft magnetic film 3b is too large, high-frequency loss occurs due to eddy currents. It is important to get the thickness.

Further, in the above configuration, the saturation magnetic flux density B _sb of the metal soft magnetic film 3b _attached to the second magnetic core half is changed to the saturation magnetic flux density B _sa of the metal soft magnetic film 3a of the first magnetic core half. If it is larger than B _sa , it is preferable to increase B _sb to at least 1.2 times B _{sa in} order to increase the asymmetry of the recording magnetic field and obtain the effect of the recording mechanism of the present invention more remarkably. When B _sb is smaller than 1.2 times B _sa, the effect of increasing the asymmetry of the recording magnetic field is hardly obtained, and the improvement of the recording / reproducing characteristics due to this is hardly recognized.

The gap length of the head can also be a factor to increase the asymmetry of the recording magnetic field and obtain the effect of the recording mechanism of the present invention more remarkably. The smaller the gap length, the greater the asymmetry of the recording magnetic field can be obtained by the configuration of the present invention,
Further preferable recording / reproducing characteristics are obtained. According to the study by the present inventors, it has been confirmed that the output difference from the head of the conventional configuration is significantly increased, particularly in a region where the gap length is 0.22 μm or less. In the future, it is expected that magnetic recording / reproducing apparatuses will have higher recording densities, and those having a minimum recording wavelength of 0.5 μm or less will be mainstream. Therefore, from the viewpoint of the reproduction gap loss, the gap length is small, preferably 0.22 μm.
m or less is preferable.

The above contents can be experimentally confirmed, for example, from the measurement results of the recording / reproducing characteristics using the magnetic recording / reproducing apparatus and the drum tester of the present invention described later.

As a metal soft magnetic film having a saturation magnetic flux density of 0.8 T or more, for example, a Co-based amorphous alloy film or a sendust film is suitable. Further, a metal soft magnetic film having a higher saturation magnetic flux density, such as a Co-based superstructure nitride alloy film having a saturation magnetic flux density exceeding 1.3 T or an Fe-based microcrystalline film having a saturation magnetic flux density exceeding 1.5 T may be used.

A configuration in which the saturation magnetic flux density B _sb of the metal soft magnetic film 3b _attached to the second magnetic core half is larger than the saturation magnetic flux density B _sa of the metal soft magnetic film 3a of the first magnetic core half. Are simultaneously realized, for example, a Co-based amorphous alloy film or a sendust film having a saturation magnetic flux density of about 1 T is used for the metal soft magnetic film 3a of the first magnetic core half, and the second magnetic core half is formed. If a Co-based superstructure nitride film or an Fe-based microcrystalline film having a higher saturation magnetic flux density is used as the metal soft magnetic film 3b deposited on the substrate, a configuration in which B _sb is 1.2 times or more larger than B _sa can be realized. it can.

When the head shown in FIG. 1 is used particularly in a magnetic recording / reproducing apparatus such as a VTR, an azimuth angle of 10 to reduce the influence of crosstalk between adjacent tracks.
May be provided. Due to the formation of the azimuth angle 10, the gap 6 is formed in a direction inclined with respect to the direction of relative movement between the head and the medium. Therefore, the azimuth angle is the same as the scanning angle of the rotary head in the VTR with respect to the length direction of the magnetic tape. Are not exactly the same. However, even if the azimuth angle is set within a practical range, the inclination direction of the recording magnetic field near the leading edge is generally close to the inclination direction of the easy axis of the medium, and conversely, the inclination direction of the recording magnetic field near the trailing edge. Is close to the hard axis direction of the medium, the recording mechanism of the present invention can be sufficiently realized to improve the recording / reproducing characteristics.

FIGS. 2 and 3 show a first ferromagnetic ferrite surface formed by depositing a metal soft magnetic film on a ferromagnetic ferrite surface as in FIG.
A MIG type ring-type magnetic head in which a magnetic circuit having a gap is formed by opposing the magnetic core half and the second magnetic core half to each other, and the metal adhered to the gap forming surface of the second magnetic core half 1 shows a configuration example different from FIG. 1 for a ring-type magnetic head in which the average thickness of the soft magnetic film is larger than the average thickness of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half. It is a thing. (A) shows the configuration of the medium sliding surface of the ring type magnetic head, and (b) shows a configuration example of the core cross section in the gap length direction 7. The interface between the metal soft magnetic films 3a and 3b and the ferrite 4 is shown in FIG.
It is known that by forming the gap 6 in a non-parallel manner as described above, it is possible to reduce noise due to a reproduced signal from a pseudo gap formed by a non-magnetic portion existing at the same interface. 2 and 3, the average thickness of the metal soft magnetic film 3a applied to the first magnetic core half is 1.5 times.
μm or more, and the average thickness of the metal soft magnetic film 3b applied to the second magnetic core half is twice as large as the average thickness of the metal soft magnetic film 3a applied to the first magnetic core half. The effect of the present invention can be obtained similarly to the configuration of FIG. Further, the effect of increasing the asymmetry of the recording magnetic field by increasing B _sb to 1.2 times or more of B _sa can be obtained in the same manner as in the configuration of FIG.

(Second Configuration Example of Ring-Type Magnetic Head) Next, as a second configuration, a gap is formed by opposing a first magnetic core half and a second magnetic core half made of a ferromagnetic material. A ring-type magnetic head constituting a magnetic circuit.
The saturation magnetic flux density of the magnetic material forming the gap forming surface of the magnetic core half and the vicinity thereof is smaller than the saturation magnetic flux density of the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof, and A ring-type magnetic head in which the magnetic path cross-sectional area of the gap forming surface of the first magnetic core half is smaller than the magnetic path cross-sectional area of the gap forming surface of the second magnetic core half will be described in detail.

FIGS. 4 and 5 show an example of a stacked ring type magnetic head having the second configuration. FIGS. 4 and 5 are diagrams each showing a configuration example of a cross section of the core in the relative movement direction 14 between the head and the medium, and FIGS. According to the configuration of the present invention, in the recording process, the first magnetic core half is used as the leading side, and the second magnetic core half is used as the trailing side. Here, the gap depth d _g is shown in FIGS. 2 and 3B. In general, in the ring-type magnetic head, the length of the gap forming surface of the first magnetic core half in the gap width direction 8 is substantially equal to the length of the gap forming surface of the second magnetic core half in the gap width direction. It is manufactured to become. In such a case, the fact that the magnetic path cross-sectional area of the gap forming surface of the first magnetic core half is smaller than the magnetic path cross-sectional area of the gap forming surface of the second magnetic core half means that the gap depth d _g May be determined by the magnetic path cross-sectional shape on the gap forming surface of the first magnetic core half 1.

Such a configuration is the first type as shown in FIG.
The simplest implementation is achieved by providing the winding window 11 only in the magnetic core half. Also, in the configuration in which the winding window 11 is provided on both magnetic core halves, as shown in FIG.
The configuration in which the magnetic path cross-sectional area of the gap forming surface of the magnetic core half is smaller than the magnetic path cross-sectional area of the gap forming surface of the second magnetic core half can be realized.

As described above, the magnetic path cross-sectional area of the gap forming surface of the first magnetic core half is smaller than the magnetic path cross-sectional area of the gap forming surface of the second magnetic core half. The feature alone is not sufficient to obtain a steeper asymmetric magnetic field on the trailing side with respect to the gap center line. In the ring type magnetic head of the second configuration of the present invention, the saturation magnetic flux density B _sb of the magnetic material constituting the gap forming surface of the second magnetic core half and the vicinity thereof is formed by the gap formation of the first magnetic core half. The magnetic path cross-sectional area of the gap forming surface of the first magnetic core half is set to be larger than the saturation magnetic flux density B _sa of the magnetic material constituting the surface and the vicinity thereof. By simultaneously realizing a configuration smaller than the magnetic path cross-sectional area, the effect of improving the recording / reproducing characteristics by the recording mechanism of the present invention is enhanced.

As a result, compared with a head having a configuration in which B _sb is made larger than B _sa , the reproduction output particularly in the high linear recording density region is increased, and the effect of reducing the optimum recording current is obtained. This can contribute to lower power consumption of the recording / reproducing device. For example, according to the result of recording and reproduction on the above-described obliquely anisotropic vapor-deposited tape, the optimum magnetomotive force for obtaining the maximum output at a recording wavelength of 0.5 μm is the MIG of the configuration in which B _sb is larger than B _sa. About 0.4AT _{pp for} type head
Which was whereas at, the head that achieves the second head configuration at the same time, the magnetic core structure shown in FIGS. 6 and 7, have been obtained small value of not more than about 0.35 at _pp 0.3.

[0055] Also in the second head arrangement in the same manner as the first head configuration, in order to obtain the magnetization reversal capability of leading side head magnetic field sufficient, B _sa requires more 0.8 T. Also, when a difference is provided between B _sb and B _sa , in order to obtain sufficient asymmetry of the recording magnetic field, B _{sb is set} to be 1.2 times or more of B _sa as in the case of application to the first head configuration. Preferably, the gap length is increased to 0.22 μm or less.

As for the magnetic material constituting the gap forming surface of the first magnetic core half and the second magnetic core half and the vicinity thereof, as in the first head configuration, a Co-based amorphous film and a sendust film are used. A metal soft magnetic film such as a Co-based superstructure nitrided alloy film and an Fe-based microcrystalline film may be used.

The second head configuration can be realized not only in a stacked-type ring-type magnetic head but also in a MIG-type ring-type magnetic head as shown in FIGS. 6 and 7, for example. In this case, in the first head configuration, the average thickness of the metal soft magnetic film deposited on the gap forming surface of the second magnetic core half was deposited on the gap forming surface of the first magnetic core half. By simultaneously realizing a configuration larger than the average thickness of the metal soft magnetic film, the recording magnetic field increases asymmetry and the trailing edge side magnetic field gradient increases, so that more preferable recording / reproducing characteristics can be obtained.

(Third Configuration Example of Ring-Type Magnetic Head) Next, as a third configuration, a gap is formed by opposing a first magnetic core half and a second magnetic core half made of a ferromagnetic material. A ring-type magnetic head constituting a magnetic circuit.
The magnetic material forming the gap forming surface of the magnetic core half and the vicinity thereof and the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof are composed of a plurality of the same elements as main components. Alternatively, the magnetic material forming the gap forming surface of the first magnetic core half and the vicinity thereof includes B and C as elements constituting the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof. , N, and O, and the saturation magnetic flux density of the magnetic material forming the gap forming surface of the first magnetic core half and its vicinity is adjusted to the second magnetic core half. A ring type magnetic head smaller than the saturation magnetic flux density of the magnetic material forming the gap forming surface of the body and its vicinity will be described in detail.

According to the present invention, as one method for realizing a magnetic head that generates a recording magnetic field asymmetric with respect to the gap center line with a large magnetic field gradient on the trailing edge side, the gap forming surface of the second magnetic core half is used. And the saturation magnetic flux density B _sb of the magnetic material constituting the vicinity thereof is larger than the saturation magnetic flux density B _sa of the magnetic material constituting the vicinity of the gap forming surface of the first magnetic core half and the vicinity thereof. However, in order to realize the above configuration, the first
When the magnetic material forming the gap forming surface of the magnetic core half and its vicinity and the magnetic material forming the gap forming surface of the second magnetic core half and its vicinity are made of different kinds of soft metal magnetic films. Is often disadvantageous from the viewpoint of productivity. For example, when the metal soft magnetic film 3a in the first magnetic core half and the metal soft magnetic film 3b in the second magnetic core half are composed mainly of different elements, completely different manufacturing apparatuses or manufacturing apparatuses are used. May require conditions. Further, when the different types of soft magnetic films are manufactured using the same device, the constituent elements of each other are mixed as impurities,
It can also cause deterioration of magnetic properties.

The third head configuration is a configuration for preventing the above-mentioned reduction in productivity. The third head configuration includes a metal soft magnetic film on the first magnetic core side and a second magnetic head.
It is proposed that the metal soft magnetic film on the core side is made up of the same kind of element as a main component and that the composition ratio of the two is made different to provide a difference in the saturation magnetic flux density between the two.

As a metal soft magnetic film suitable for such a configuration, for example, there are an Fe-based and Co-based nitride film or oxide film produced by a reactive sputtering method. As a typical example, for example, in a Fe-based nitride microcrystalline film, the saturation magnetic flux density can be reduced from about 1 T to 1.6 T by a simple operation such as changing the nitrogen thickness during sputtering in a region where good soft magnetic characteristics can be obtained. It is possible to change to a range. From this range, a film having a high saturation magnetic flux density may be provided on the second magnetic core side, and a film having a low saturation magnetic flux density may be provided on the first magnetic core side. In this case, the main component elements are the same and only the composition ratio is different. Therefore, even when the first magnetic core half and the second magnetic core half are manufactured by the same device, adverse effects on the magnetic characteristics due to the inclusion of impurities and the like are small. For example, it is possible to provide a very simple manufacturing process excellent in reproducibility and productivity, as compared with a configuration in which different types of films such as sendust and Fe-based nitride microcrystal films are disposed on the first and second magnetic cores, respectively. .

The magnetic material forming the gap forming surface of the first magnetic core half and the vicinity thereof is changed to the element forming the magnetic material forming the gap forming surface of the second magnetic core half and the vicinity thereof. The magnetic material constituting the gap forming surface of the first magnetic core half and the vicinity thereof has a saturation magnetic flux density of the second magnetic material, which is formed by adding at least one element selected from B, C, N and O. The saturation magnetic flux density of the magnetic material constituting the gap forming surface of the magnetic core half and its vicinity may be smaller than that.

These elements are used for the first step in the sputtering method.
Can be easily added to the metal soft magnetic film on the magnetic core side, and the saturation magnetic flux density is smaller than the saturation magnetic flux density of the metal soft magnetic film on the second magnetic core side while maintaining good soft magnetic characteristics. can do. In addition, since the addition amount of these elements may be very small, it is not necessary to make the main components of the metal soft magnetic film on the first magnetic core side and the metal soft magnetic film on the second core side largely different. Therefore, even when the first magnetic core half and the second magnetic core half are manufactured by the same apparatus, the mixing of impurities and the like is relatively small, and a simple manufacturing process excellent in reproducibility and productivity is realized. Can be provided.

The above configuration can be widely applied to various Fe-based and Co-based metal soft magnetic films having soft magnetic characteristics suitable for a magnetic head material. For example, already B,
It may be based on a metal soft magnetic film containing at least one element selected from C, N and O. In such a case, the metal soft magnetic film forms the vicinity of the gap on the second magnetic core side. Further, the vicinity of the gap on the first magnetic core side may be constituted by a metal soft magnetic film having a composition in which an element not contained in the metal soft magnetic film is selected from B, C, N and O.

In order to realize the third head configuration, both the metal soft magnetic film on the first magnetic core side and the metal soft magnetic film on the second magnetic core side are composed of a plurality of types of films having different saturation magnetic flux densities. There is also a method of providing a difference in the saturation magnetic flux density of the metal soft magnetic film between the two magnetic cores by using a multilayer film and making the composition ratio between the two magnetic cores different. 8 and 9 show examples of the configuration of such a head. FIGS. 8 and 9 show examples of the configuration of the medium sliding surface of the ring type magnetic head. As in FIGS. 1 to 7, the right side of the gap 6 is the first magnetic core half and the left side is the second magnetic core. It is shown as a magnetic core half. FIG. 8 shows a configuration example of a laminated type head.
FIG. 9 shows a configuration example of the MIG type head.

For example, in the examples shown in FIGS. 8 and 9, the gap forming surface and the vicinity of both the first magnetic core half and the second magnetic core half have three metal soft magnetic films 3b and two metal soft magnetic films 3b. It is composed of a laminated film composed of a total of five layers of the metal soft magnetic film 3a. Here, it is assumed that the saturation magnetic flux density B _sb of the metal soft magnetic film 3b is higher than the saturation magnetic flux density B _sa of the metal soft magnetic film 3a. In this case, the layer thickness ratio of the metal soft magnetic film 3b on the side of the second magnetic core to the metal soft magnetic film 3a is made larger than the layer thickness ratio on the side of the first magnetic core. In this case, the saturation magnetic flux density of the metal soft magnetic film can be made larger than the saturation magnetic flux density of the metal soft magnetic film on the first magnetic core side.

For the metal soft magnetic film having the structure shown in FIGS. 8 and 9, for example, an Fe-based or Co-based nitride film or oxide film formed by a reactive sputtering method is suitable. In these films, a laminated film of the metal soft magnetic films 3a and 3b having different saturation magnetic flux densities can be easily produced by changing the nitrogen or oxygen thickness in the film formation at a constant period.

The metal soft magnetic films 3a and 3b may have completely different compositions, but from the viewpoint of productivity, it is preferable to use the same element as the main component as described above.

In particular, when the metal soft magnetic films 3a and 3b have completely different compositions,
In some cases, a battery effect occurs due to a difference in work function between a and 3b, and sufficient corrosion resistance cannot be ensured. In such a case, a method of making the interface between the metal soft magnetic films 3a and 3b unclear or making the composition ratio between the metal soft magnetic films 3a and 3b uniform by heat treatment or the like after film formation. Can also be taken.

FIGS. 8 and 9 show the case where the metal soft magnetic film has a structure in which two types of films are laminated. However, even in the case where the metal soft magnetic film has a configuration in which three or more types of films are laminated. Good. Also, the number of layers is not limited to the five layers shown in FIGS. For example, the effects of the present invention can be similarly obtained even in a configuration having different numbers of laminations on the first core side and the second core side.

Further, the third head configuration is such that both the metal soft magnetic film on the first magnetic core side and the metal soft magnetic film on the second magnetic core side have a laminated structure of a metal soft magnetic film and a non-magnetic insulating film. However, by making the composition ratio between the metal soft magnetic film and the non-magnetic insulating film in both magnetic cores different, the configuration can also be realized by providing a difference in saturation magnetic flux density between the metal soft magnetic films in both magnetic cores. FIGS. 10 and 11 show examples of the configuration of such a head. FIGS. 10 and 11 are diagrams showing a configuration example of the medium sliding surface of the ring-type magnetic head. As in FIGS. 1 to 7, the right side of the gap 6 is the first magnetic core half and the left side is the second magnetic core. It is shown as a magnetic core half.
FIG. 10 shows a configuration example of a laminated type head, and FIG.
3 shows a configuration example of a type head.

For example, in the example shown in FIG. 10, the nonmagnetic insulating film 13 has five layers on the first magnetic core side, whereas only two layers exist on the second magnetic core side. Similarly, in the example shown in FIG. 11, the nonmagnetic insulating film 13 has four layers on the first magnetic core side, whereas only two layers exist on the second magnetic core side. That is, by making the composition ratio of the metal soft magnetic film 3 to the nonmagnetic insulating film 13 on the second magnetic core side larger than the composition ratio on the first magnetic core side,
The saturation magnetic flux density on the gap forming surface on the magnetic core side and the vicinity thereof can be made larger than the saturation magnetic flux density on the first magnetic core side.

In the above configuration, it is not possible to use a simple manufacturing method such as changing the gas partial pressure during sputtering at a constant cycle. However, for example, by using a technique of preparing two types of targets, a metal soft magnetic film and a non-magnetic insulating film, in a vacuum vessel and sputtering them alternately,
Compared with a configuration in which the metal soft magnetic films 3a and 3b have completely different compositions, the reproducibility and productivity are much simpler.

The presence of the non-magnetic insulating film 13 is also effective in reducing the eddy current loss in the metal soft magnetic film 3. For example, in the first head configuration described above, the average film thickness of the metal soft magnetic film 3b on the second magnetic core side is larger than twice the average film thickness of the metal soft magnetic film 3a on the first magnetic core side. However, if the average thickness of the metal soft magnetic film 3b is too large, high-frequency loss due to eddy current occurs. However, if the configuration of FIG. 11 is simultaneously realized with the first head configuration as shown in FIG. 1, even if the average thickness of the metal soft magnetic film 3b is sufficiently increased, the high-frequency loss due to the eddy current can be reduced. Therefore, there is much room for obtaining an asymmetric recording magnetic field. Further, in the configuration shown in FIG. 11, the saturation magnetic flux density at and near the gap forming surface on the second magnetic core side is made larger than the saturation magnetic flux density on the first magnetic core side, thereby increasing the asymmetry of the recording magnetic field. Is also more preferable since it is also obtained.

On the other hand, as the composition ratio of the nonmagnetic insulating film 13 increases, the saturation magnetic flux density on the gap forming surface and in the vicinity thereof decreases. In particular, care must be taken so that the saturation magnetic flux density at and near the gap forming surface on the first magnetic core side does not become smaller than 0.8T. FIG.
0, the non-magnetic insulating film 13
If the film thickness of the non-magnetic insulating film 13 is large, a signal may be missed in a position where the nonmagnetic insulating film 13 exists in the track width direction. In order to prevent this, the thickness of the nonmagnetic insulating film 13 needs to be sufficiently small in a range where a difference in saturation magnetic flux density can occur between the first magnetic core side and the second magnetic core side. . Preferably, the thickness is set to several hundreds nm or less. Alternatively, a method may be adopted in which the interface between the metal soft magnetic film 3 and the nonmagnetic insulating film 13 is made unclear and the composition is made uniform by heat treatment after film formation. However, in this case, the effect of reducing the eddy current is likely to be lost. Therefore, it is important to obtain an optimum configuration in consideration of the frequency band used by the magnetic recording / reproducing apparatus on which the head is mounted.

(Exemplary Configuration of Magnetic Recording / Reproducing Apparatus) The magnetic recording / reproducing apparatus of this embodiment uses a ring-type magnetic head having at least one of the above three configurations, with the first magnetic core half as the leading side. It is configured by being mounted on a rotary cylinder of a commercially available VTR, and its basic configuration is as shown in FIG.

Originally, it is clear that in order to obtain the effect of the present invention, the first magnetic core half needs to be on the leading side in the recording process, and the second magnetic core is required in the reproducing process. The half can be the leading side. However, in the magnetic recording / reproducing apparatus of this embodiment, the first magnetic core half is used as the leading side in both the recording process and the reproducing process due to the original configuration of the modified commercial VTR.

Further, in order to perform a recording / reproducing experiment in a high linear recording density region exceeding the standard of a commercially available VTR, the recording amplifier, the reproducing amplifier and the like are slightly modified.

The relative movement direction between the ring-type magnetic head and the magnetic recording medium in the present magnetic recording / reproducing apparatus can be set according to the direction of the tape when the above-described vapor deposition tape is inserted into a commercially available cassette. The evaporation tape has a recording magnetic field near the leading edge of the ring-type magnetic head and the axis of easy magnetization of the evaporation tape within the slope of the evaporation tape magnetic layer including the relative movement direction of the ring-type magnetic head and the evaporation tape during recording. The vapor-deposited tape was inserted into the cassette so as to have the structure of the present invention inclined to the same side with respect to the film normal to the magnetic layer.

The recording / reproducing characteristics of the obliquely anisotropic vapor-deposited tape described in the present embodiment were measured by the above-mentioned magnetic recording / reproducing apparatus, and using the ring-type magnetic head having the configuration of the present invention described above. It was confirmed that excellent characteristics were obtained.

For example, when compared with a MIG type head using a sendust mounted on a commercial VTR as a metal soft magnetic film, it has the first to third configurations of the present invention having a gap length of 0.2 μm equivalent to this. When a magnetic head is mounted, 1.5 to 3 dB at a recording wavelength of 0.5 μm,
At a recording wavelength of 0.25 μm, a normalized reproduction output as high as 2.5 dB to 6 dB was obtained. On the other hand, with respect to noise, a value equal to or lower than that of the head having the conventional configuration was obtained. The configuration of the present invention is to improve the characteristics in the recording process due to the decrease in the magnetization transition width. Therefore, basically, even if the reproduction output increases, it is unlikely that the medium noise increases. Rather, in the case where the medium noise is caused by the non-uniformity of the domain wall shape in the magnetization transition region, it is considered that there is an effect of reducing the noise by reducing the magnetization transition width. Therefore, the effect of increasing the reproduction output in the present invention is directly reflected in the improvement of the S / N in the magnetic recording / reproducing apparatus.

In the above-described embodiment, a vapor-deposited tape having a magnetic layer containing Co and O as main components was used as the magnetic recording medium. However, the effect of the present invention is limited by the composition of the magnetic layer. Rather, magnetic recording media composed of various compositions can be used as long as a highly oriented oblique anisotropic medium is realized.

Further, in this embodiment, an example of the magnetic recording / reproducing apparatus of the VTR type has been described, but the present invention is not limited to this, and various types of magnetic recording media such as a magnetic card and a magnetic disk are used. It is useful for a magnetic recording / reproducing device.

Also, the constituent materials of the mounted head are not limited to the materials shown in this embodiment, and various kinds of materials are applied as long as the configuration of the ring type magnetic head of the present invention is realized. be able to.

[0085]

According to the present invention, a ring-type magnetic head having a recording magnetic field distribution suitable for recording on an obliquely anisotropic magnetic recording medium can be provided. This makes it possible to remarkably improve the recording / reproducing characteristics particularly in a high linear recording density region, and to realize a magnetic recording / reproducing apparatus capable of recording at a higher density than before. That is, according to the configuration of the present invention, it is possible to provide a magnetic recording / reproducing apparatus having a smaller capacity and a larger capacity than before.

According to the present invention, the power consumption of the magnetic recording / reproducing apparatus can be reduced by reducing the optimum recording current.

Further, according to the present invention, in a ring type magnetic head manufactured by a very simple manufacturing process excellent in reproducibility and productivity, a recording magnetic field distribution suitable for recording on the obliquely anisotropic magnetic recording medium is provided. Can be realized. That is, the ring-type magnetic head of the present invention does not sacrifice productivity to obtain the effect,
It can be provided at a low cost, as in a conventional ring-type magnetic head.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration example of a magnetic head of the present invention. FIG. 1 (a) is a diagram showing a medium sliding surface of a magnetic head. FIG.

FIGS. 2A and 2B show a configuration example of a magnetic head of the present invention. FIG. 2A shows a medium sliding surface of the magnetic head. FIG. 2B shows a core cross section in a gap length direction.

FIGS. 3A and 3B are diagrams illustrating a configuration example of a magnetic head according to the present invention; FIG. 3A is a diagram illustrating a medium sliding surface of the magnetic head; FIG.

4A and 4B are diagrams showing a configuration example of a magnetic head of the present invention. FIG. 4A is a diagram showing a medium sliding surface of the magnetic head. FIG. 4B is a diagram showing a cross section of a core in a direction of relative movement with the medium.

FIGS. 5A and 5B show a configuration example of a magnetic head of the present invention. FIG. 5A shows a medium sliding surface of the magnetic head. FIG. 5B shows a core cross section in the direction of relative movement with the medium.

6A and 6B are diagrams showing a configuration example of a magnetic head of the present invention. FIG. 6A is a diagram showing a medium sliding surface of the magnetic head. FIG. 6B is a diagram showing a cross section of a core in a direction of relative movement with the medium.

FIGS. 7A and 7B show a configuration example of a magnetic head of the present invention. FIG. 7A shows a medium sliding surface of the magnetic head. FIG. 7B shows a core cross section in a direction of relative movement with respect to the medium.

FIG. 8 is a diagram showing a configuration example of a medium sliding surface of the magnetic head of the present invention.

FIG. 9 is a diagram showing a configuration example of a medium sliding surface of the magnetic head of the present invention.

FIG. 10 is a diagram showing a configuration example of a medium sliding surface of the magnetic head of the present invention.

FIG. 11 is a diagram showing a configuration example of a medium sliding surface of the magnetic head of the present invention.

FIG. 12 is a diagram showing a configuration example of a magnetic recording / reproducing apparatus according to the present invention.

FIG. 13 is a diagram showing an example of a configuration inside a vacuum evaporation apparatus for manufacturing an evaporation tape having oblique anisotropy.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st magnetic core half 2 2nd magnetic core half 3, 3a, 3b Metal soft magnetic film 4 Ferrite 5 Glass material 6 Gap 7 Gap length direction 8 Gap width direction 9 Track width direction 10 Azimuth angle 11 turns Line window 12 Non-magnetic substrate 13 Non-magnetic insulating film 14 Relative moving direction of head and medium 15 Leading edge 16 Trailing edge 17 Gap center line 18 Recording magnetic field 19 Direction of relative movement of head to medium 20 Magnetic layer 21 Substrate 22 Easy magnetization Axis 23 Film normal 24 Recording magnetization 25 Magnetic transition region 26 Region between magnetization transitions 27 Cylindrical can 28 Substrate running direction 29 Supply roll 30 Winding roll 31A, 31B Shielding plate 32 Oxygen inlet 33 Evaporation source 34 Evaporated atoms

────────────────────────────────────────────────── ─── Continuing on the front page (72) Noriyasu Echigo, Inventor 1006 Ojidoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-89806 (JP, A) JP-A-63- 271703 (JP, A) JP-A-2-193307 (JP, A) JP-A-6-195628 (JP, A) JP-A-2-223006 (JP, A) JP-A-63-81609 (JP, A) JP-A-60-201512 (JP, A) JP-A-60-57512 (JP, A) JP-A-5-20603 (JP, A) JP-A-62-267702 (JP, A) JP-A-4-351701 (JP, A) JP-A-3-288301 (JP, A) JP-A-4-251406 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 5/00-5 / 02 G11B 5/127-5/255 G11B 5/62-5/82

Claims (8)

(57) [Claims] 1. A metal constituting a magnetic circuit having a gap by opposing a first magnetic core half and a second magnetic core half formed by applying a metal soft magnetic film on a ferromagnetic ferrite surface. In the in-gap type ring type magnetic head, the average thickness of the metal soft magnetic film deposited on the gap forming surface of the first magnetic core half is 1.5 μm or more, and the gap of the second magnetic core half is the average thickness of the metal soft magnetic film deposited on forming surface, much larger than the average film twice the thickness of the metallic soft magnetic film deposited on the gap forming surface of the first magnetic core half,
And attaching the first magnetic core half to the gap forming surface.
The saturation magnetic flux density of the metal soft magnetic film thus formed is increased by the second magnetic core.
Saturation magnetism of a soft metal magnetic film deposited on the gap forming surface of a half body
A magnetic head characterized by being smaller than a bundle density . 2. A ring-type magnetic head comprising a first magnetic core half made of a ferromagnetic material and a second magnetic core half being opposed to each other to form a magnetic circuit having a gap. The magnetic material forming the gap forming surface and its vicinity and the magnetic material forming the gap forming surface of the second magnetic core half and its vicinity are composed of a plurality of the same elements as main components, and the first magnetic material. gap forming surface of core half and the saturation magnetic flux density of the magnetic material constituting the neighborhood rather smaller than the saturation magnetic flux density of the magnetic material constituting the gap forming surface and the vicinity thereof in a second magnetic core halves, or
The first magnetic core half and the second magnetic core
Magnetic material forming the gap forming surface of the half body and its vicinity
The material has a configuration in which a soft magnetic film and a non-magnetic insulating film are laminated,
And the gap forming surface of the first magnetic core half and the vicinity thereof
Of the total thickness of the soft magnetic film in the magnetic material forming the side
The ratio of the total laminated thickness of the non-magnetic insulating film to the second magnetic core half
Material forming the gap formation surface and its vicinity
Product of non-magnetic insulating film with respect to total thickness of soft magnetic film
A magnetic head characterized by being smaller than the ratio of the layer thicknesses . 3. A ring type magnetic head comprising a first magnetic core half made of a ferromagnetic material and a second magnetic core half being opposed to each other to form a magnetic circuit having a gap, wherein the first magnetic core half is formed. The magnetic material forming the gap forming surface of the second magnetic core half and the magnetic material forming the vicinity thereof are B, C,
The magnetic material forming the gap forming surface of the first magnetic core half and its vicinity and having a saturation magnetic flux density of the second magnetic core half which is formed by adding at least one element selected from N and O; A magnetic head characterized by being smaller than a saturation magnetic flux density of a magnetic material forming the gap forming surface and its vicinity. 4. The magnetic recording medium of the easy magnetization axis is inclined with respect to the film normal of the magnetic layer, it is formed by depositing a metallic soft magnetic film on the ferromagnetic ferrite surface
The first magnetic core half and the second magnetic core half
A metal-in component that forms a magnetic circuit with a gap
The first magnetic core is a gap type ring type magnetic head.
Average of soft metal magnetic film deposited on the gap forming surface of the half
The thickness of the second magnetic core half is 1.5 μm or more, and
The average thickness of the metal soft magnetic film deposited on the cap forming surface is
Metal soft magnetism adhered to the gap forming surface of the magnetic core half
A magnetic recording / reproducing apparatus for recording a signal using a magnetic head larger than twice the average film thickness of a magnetic recording medium, the magnetic recording medium comprising a relative movement direction of the magnetic head and the magnetic recording medium in a recording process In the normal of the layer, the recording magnetic field near the leading edge of the magnetic head and the easy axis of magnetization of the magnetic recording medium are inclined to the same side with respect to the film normal of the magnetic layer of the magnetic recording medium, and the recording process is performed. Wherein the first magnetic core half of the magnetic head is on the leading side and the second magnetic core half is on the trailing side in the direction of relative movement between the magnetic head and the magnetic recording medium. Magnetic recording and reproducing apparatus. 5. A first magnetic core half made of a ferromagnetic material and a second magnetic core , wherein a magnetic recording medium whose easy axis is inclined with respect to the film normal of the magnetic layer.
Construct a magnetic circuit with a gap by facing the halves
Ring type magnetic head, and a gap of the first magnetic core half.
Saturation Magnetism of the Magnetic Material Constituting the Tap Forming Surface and Its Neighbor
When the flux density is higher than the gap forming surface of the second magnetic core half,
Smaller than the saturation magnetic flux density of the magnetic material forming the vicinity of
Magnetic path disconnection of the gap forming surface of the first magnetic core half
Magnetic path cross section of the gap forming surface of the second magnetic core half having an area
A magnetic recording / reproducing apparatus for recording a signal using a magnetic head smaller than the product , comprising: The recording magnetic field near the leading edge of the head and the axis of easy magnetization of the magnetic recording medium are inclined to the same side with respect to the film normal of the magnetic layer of the magnetic recording medium, and the magnetic head and the magnetic recording medium in a recording process A magnetic recording / reproducing apparatus, wherein a first magnetic core half of the magnetic head is on a leading side and a second magnetic core half is on a trailing side in a relative movement direction of a medium. 6. A first magnetic core half made of a ferromagnetic material and a second magnetic core formed on a magnetic recording medium whose easy axis is inclined with respect to the film normal of the magnetic layer.
Construct a magnetic circuit with a gap by facing the halves
Ring type magnetic head, and a gap of the first magnetic core half.
Magnetic material forming the tape forming surface and its vicinity and the second
Constituting the gap forming surface of the magnetic core half and its vicinity
Magnetic material is composed of a plurality of the same elements as main components.
And the gap forming surface of the first magnetic core half and the
The saturation magnetic flux density of the magnetic material constituting the vicinity of
Magnets that make up the gap-forming surface of the core half and its vicinity
A magnetic recording / reproducing apparatus for recording a signal using a magnetic head having a saturation magnetic flux density smaller than a saturation magnetic flux density of a conductive material, wherein a method of forming a magnetic layer of a magnetic recording medium including a relative moving direction of the magnetic head and the magnetic recording medium in a recording process. In the plane, the recording magnetic field near the leading edge of the magnetic head and the axis of easy magnetization of the magnetic recording medium are inclined to the same side with respect to the film normal of the magnetic layer of the magnetic recording medium, and the magnetic field in the recording process is reduced. The magnetic head according to claim 1, wherein the first magnetic core half of the magnetic head is on the leading side and the second magnetic core half is on the trailing side in the direction of relative movement between the head and the magnetic recording medium. Recording and playback device. 7. A first magnetic core half made of a ferromagnetic material and a second magnetic core , wherein a magnetic recording medium whose easy axis is inclined with respect to the film normal of the magnetic layer.
Construct a magnetic circuit with a gap by facing the halves
Ring type magnetic head, and a gap of the first magnetic core half.
The magnetic material forming the top forming surface and its vicinity is the second material.
Form the gap forming surface of the magnetic core half and its vicinity
Selected from B, C, N , and O as constituent elements of the magnetic material.
A composition comprising at least one element added thereto,
Gap formation surface of the first magnetic core half and its vicinity
The saturation magnetic flux density of the magnetic material forming
Material forming the gap forming surface of the body and its vicinity
A magnetic recording / reproducing apparatus for recording a signal using a magnetic head having a saturation magnetic flux density smaller than a saturation magnetic flux density of a magnetic layer of a magnetic recording medium including a relative moving direction of the magnetic head and the magnetic recording medium in a recording process. Wherein the recording magnetic field near the leading edge of the magnetic head and the easy axis of magnetization of the magnetic recording medium are inclined to the same side with respect to the film normal of the magnetic layer of the magnetic recording medium, and A magnetic recording / reproducing apparatus having a configuration in which a first magnetic core half of the magnetic head is on a leading side and a second magnetic core half is on a trailing side in a relative movement direction of the magnetic recording medium. apparatus. 8. An angle between an easy axis direction of the magnetic recording medium and a film normal of the magnetic layer is not less than 50 ° and not more than 85 °,
And the magnetization easy axis of the coercive force is at 80 kA / m or more and a magnetic recording according to any one of claims 4-7 uniaxial anisotropy constant is equal to or is 10 ⁵ J / m ³ or more Playback device.