JPH09212856A - Production of magnetic recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To well execute the surface treatment of a magnetic recording medium having ferromagnetic metallic thin films and to prevent the fault to the original plate of a vapor deposited tape by subjecting a nonmagnetic base to a lapping treatment in the direction nearly perpendicular to the traveling direction of this base. SOLUTION: A first polishing device 12 is so constituted that a lapping tale 14 is taken up on a lapping tape take-up roll 16 via fixing members 13, 13 from a lapping tape feed roll 15. This lapping tape 14 is so disposed as to come into slide-contact with the nonmagnetic base 2 in its traveling direction (X direction). Then, the splashes and dust at the time of vapor deposition sticking to the magnetic layer surface of the nonmagnetic base 2 are removed by the polishing devices 12, 21 after the magnetic metallic thin films are deposited and formed on the nonmagnetic base 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of a method for producing a magnetic recording medium in which a metal magnetic thin film is formed as a magnetic layer on a non-magnetic support by oblique vapor deposition, and more particularly to a non-magnetic support. The present invention relates to surface treatment and surface treatment of the magnetic layer.

[0002]

2. Description of the Related Art Conventionally, as a magnetic recording medium, a powder magnetic material such as an oxide magnetic powder or an alloy magnetic powder is used as a vinyl chloride-vinyl acetate copolymer, a polyester resin,
2. Description of the Related Art A coating type magnetic recording medium prepared by coating a magnetic coating material dispersed in an organic binder such as urethane resin or polyurethane resin on a non-magnetic support and drying it is widely used.

On the other hand, in the field of video tape recorders (VTRs) and the like, there is a strong demand for high-density magnetic recording in order to achieve high image quality, and as a magnetic recording medium corresponding thereto, Co-Ni alloy, C
Non-magnetic support of polyester film, polyamide, polyimide film, etc. for metal magnetic materials such as o-Cr alloys and Co-O based on plating or vacuum thin film forming technology (vacuum evaporation method, sputtering method, ion plating method, etc.) A so-called ferromagnetic metal thin film coating type magnetic recording medium, which is directly deposited on the body as a magnetic layer, has been proposed and has attracted attention.

In this magnetic recording medium of the ferromagnetic metal thin film coating type, a ferromagnetic metal thin film which is a magnetic layer is formed in order to improve electromagnetic conversion characteristics and obtain a larger output. In this case, oblique vapor deposition in which a magnetic material is obliquely vapor-deposited has been proposed and put to practical use. It is considered that such a metal thin film medium will become the mainstream of high density magnetic recording media in the future because of its superior magnetic properties.

By the way, since the magnetic layer formed by this oblique vapor deposition is usually as thin as about 200 nm, the adhered matter on the non-magnetic support or the deformation of the shape interferes with the contact with the magnetic head, resulting in poor contact. Since it is likely to be dropped out, careful attention has been paid to the generation of deposits in the manufacturing process of the non-magnetic support and the deformation of the shape due to overturning.

However, it is not possible to completely remove the fine dust of the magnetic material in the vapor deposition process, and the generation of fine heat loss in the vapor deposition process and the dropout caused by the fine dust in the vapor deposition apparatus become a problem. I couldn't reduce it to a level that didn't exist. In particular, this heat loss causes a partial deterioration of the characteristics of the magnetic recording layer, which causes hitting defects and so-called dropout.

As a countermeasure against this dropout, the applicant of the present application has already proposed a method of lapping the magnetic layer surface as shown in JP-A-63-167425 and JP-A-2-7225. There is. In this lapping process, dust and foreign matters attached to the surface of the vapor deposition tape raw material are removed by sliding a lapping tape having a strong abrasive force in the same direction as the running direction of the vapor deposition tape raw material.

[0008]

As described above, according to the conventional method, the lapping tape is slidably contacted in the same direction as the running direction of the vapor deposition tape stock to perform the lapping process.

However, in such a conventional method,
Since the feeding speed of the wrapping tape, etc. is incomparably slower than the feeding speed of the vapor deposition tape raw material, foreign matter and dust etc. of the vapor deposition tape raw material adhering to the wrapping tape, on the contrary, scratch the vapor deposition tape raw material. There was a bad effect of putting it on.

Further, in the conventional lapping method,
Since the feed speed is changed in the same direction as the running direction of the vapor deposition tape stock, foreign matter attached to the wrapping tape, etc. will be damaged for a considerable length in the length direction of the vapor deposition tape stock. was there.

Therefore, in order to improve such a situation, various measures have been taken in setting conditions and the like during the lapping process. For example, one of them is an attempt to suppress the occurrence of scratches by running the wrapping tape in an oblique direction with respect to the original vapor deposition tape.

However, none of the devices devised based on the conventional method are sufficiently effective. On the other hand,
Even if the conventional method is drastically changed and a sufficient effect is exhibited, it is not preferable that the apparatus becomes large and complicated and the cost becomes high.

In particular, with the recent trend of high density recording (shorter wavelength recording) and digital recording of magnetic recording systems, it is necessary to meet these strict requirements for magnetic recording media, but conventional ones are not sufficient for such requirements. It was not possible to exert such an effect.

Therefore, the present invention has been proposed in view of the above circumstances, and it is effective to reduce the dropout of the metal thin film magnetic recording medium and to prevent the occurrence of scratches due to the surface treatment with a simple structure. It is an object of the present invention to provide a method of manufacturing a magnetic recording medium that can prevent the above problems.

[0015]

In order to solve the above problems and achieve the object, a method of manufacturing a magnetic recording medium according to the present invention comprises:
In a method of manufacturing a magnetic recording medium in which a metal magnetic thin film is formed on a non-magnetic support by oblique vapor deposition, lapping is performed in a direction substantially perpendicular to the running direction of the non-magnetic support.

Further, it is characterized in that compressed air is blown from the back side of the wrapping tape.

Further, it is characterized in that after the lapping process is carried out in a direction substantially perpendicular to the running direction of the non-magnetic support, the lapping process is carried out in the same direction as the running direction of the non-magnetic support.

Further, it is characterized in that the lapping process with the lapping tape is performed after the metal magnetic thin film is adhered and formed on the non-magnetic support.

According to the present invention, since the lapping treatment is carried out in a direction substantially perpendicular to the running direction of the non-magnetic support, the surface treatment of the ferromagnetic metal thin film magnetic recording medium can be favorably carried out, and the vapor deposition tape original fabric can be processed. Like the conventional method in which the wrapping tape is slidably contacted in the same direction as the running direction of the wrapping tape, foreign matter or dust on the wrapping tape that is attached to the wrapping tape, on the contrary, may scratch the vapor deposition tape. Will disappear.

Further, by performing the lapping process in a direction substantially perpendicular to the running direction of the non-magnetic support, foreign substances adhering to the lapping tape or the like in the lengthwise direction of the vapor deposition tape raw material as in the conventional method. It will not hurt you for a long time.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings.

Magnetic Recording Medium Manufacturing Apparatus A magnetic recording medium manufactured using the apparatus of the present invention is a ferromagnetic metal thin film type magnetic recording medium, in particular, a ferromagnetic metal thin film is formed by oblique deposition. It is a magnetic recording medium.

Therefore, in the apparatus for manufacturing a magnetic recording medium according to the present embodiment, as shown in FIG. 1, a tape-shaped non-magnetic support 2 is provided in a vacuum chamber 1 whose inside is in a vacuum state.
The feed roll 3 is rotated at a constant speed in the clockwise direction in the drawing, and the winding roll 4 is rotated in the counterclockwise direction at a constant speed.

The non-magnetic support 2 is provided in the middle of the feed roll 3 and the take-up roll 4 so as to be pulled out downward in the figure, and has a diameter larger than the diameters of the rolls 3 and 4. The cooling can 5 is provided so as to rotate at a constant speed in the clockwise direction in the figure.

The feed roll 3, the winding roll 4,
The cooling can 5 has a cylindrical shape having a length substantially the same as the width of the non-magnetic support 2, and the cooling can 5 has a cooling device (not shown) provided therein. Deformation and the like of the magnetic support 2 due to temperature rise can be suppressed.

Therefore, the non-magnetic support 2 is sequentially fed from the feed roll 3, passes through the peripheral surface of the cooling can 5, and is wound up by the winding roll 4. Guide rolls 6 and 7 are provided between the feed roll 3 and the cooling can 5 and between the cooling can 5 and the take-up roll 4, respectively. A predetermined tension is applied to the non-magnetic support 2 that runs from the cooling can 5 to the ticket-picking roll 4, so that the non-magnetic support 2 runs smoothly.

A storage container 8 is provided below the cooling can 5 in the vacuum chamber 1, and a metal magnetic material 9 is filled in the storage container 8. Further, a heating means 10 composed of an electron beam gun or the like is provided on the side of the cooling can 5.

The heating means 10 heats and evaporates the metallic magnetic material 9 filled in the storage container 8. The metallic magnetic material 9 evaporated by the heating means 10 causes the peripheral surface of the cooling can 5 to move at a constant speed. A magnetic layer is deposited and formed on the running non-magnetic support 2.

A shutter 11 is arranged between the cooling can 5 and the storage container 8 and near the cooling can 5. The shutter 11 is formed so as to cover a predetermined region of the non-magnetic support 2 that runs at a constant speed on the peripheral surface of the cooling can 5, and the shutter 12 causes the evaporated metal magnetic material 9 to be a non-magnetic support. 2 is obliquely vapor-deposited within a predetermined angle range.

In particular, this magnetic recording medium manufacturing apparatus includes a first polishing apparatus 12 for lapping the surface of the magnetic layer of the non-magnetic support 2 which runs from the guide roll 7 to the take-up roll 4. There is provided a second polishing device 21 which is further subjected to lapping treatment if necessary.

First, the first polishing device 12 has a simple structure and performs an efficient lapping process, and is provided between the guide roll 7 and the winding roll 4. Then, as shown in FIG. 2, the first polishing device 12 is provided in a direction perpendicular to the non-magnetic support 2 that runs from the guide roll 18 to the guide roll 19.

That is, in the first polishing device 12, the wrapping tape 14 is the wrapping tape feed roll 1
5 is wound on the wrapping tape winding roll 16 via the fixing members 13 and 13,
A wrapping tape 14 is arranged so as to be in slidable contact in a direction perpendicular to the running direction of the non-magnetic support 2 (direction of arrow Y in the figure) (direction of arrow X in the figure).

A blowing means 20 is provided on the back side of the wrapping tape 14. The spraying means 20 is for spraying compressed air so that the effect of the lapping process can be further enhanced.

Therefore, after the metal magnetic thin film is deposited on the non-magnetic support 2, the polishing devices 12 and 21 having the above-described structure are formed.
As a result, the splash material and dust attached to the surface of the magnetic layer of the non-magnetic support 2 during vapor deposition can be removed. The structure of the first polishing device 12 is such that the lapping tape 2 is oriented in the same direction as the conventional non-magnetic support 2.
Since it is only necessary to dispose those which slide 3 in contact with each other in the lateral direction, the structure is simple, and the installation space is not taken up so that it can be easily introduced into existing equipment.

The width of the wrapping tape 14 is 1
The one cut to 0 mm was used. Further, the feeding speed of the wrapping tape 14 may be selected such that scratches are less likely to occur during polishing, but as in the present embodiment, the length of scratch scratches is shorter than that of the conventional speed, which is relatively high. It is preferable to set a high speed.

Next, in this apparatus, the lapping roll 2 for lapping the magnetic layer surface of the non-magnetic support 2 traveling from the guide roll 7 to the winding roll 4 is used.
A second polishing device 21 in which 2 is arranged is provided. However, this second polishing apparatus is the same as the first polishing apparatus 12 described above.
Therefore, it is not always necessary to use it when the splash material or dust attached to the surface of the magnetic layer of the non-magnetic support 2 during vapor deposition is removed.

The second polishing device 21 is subjected to the lapping process by the first polishing device 12, but when the first polishing device 12 is not sufficient, the lapping process is performed. It is provided on an extension line from the first polishing device 12, that is, in line.

As shown in FIG. 2, the second polishing device 21 is provided between the guide roll 7 and the take-up roll 4, but unlike the first polishing device 12, it is a non-magnetic support. The wrapping tape 23 is slidably contacted to the 2 in the same direction. The wrapping tape 23 is wound around a large number of wrapping tape feed rolls 24 arranged in the vicinity of the wrapping roll 22 and sequentially runs on the wrapping tape 23.
Wrapping tape take-up roll 25 arranged in the vicinity of
It is supposed to be wound up.

Method of Manufacturing Magnetic Recording Medium By using the apparatus for manufacturing a magnetic recording medium having such a structure, Co
A ferromagnetic metal material such as —Ni alloy is vacuum-deposited from an oblique direction to form a magnetic layer made of a ferromagnetic metal thin film on the non-magnetic support 2.

Here, as the ferromagnetic metal thin film material for oblique vapor deposition, any material can be used as long as it is used for a normal vapor deposition tape. For example, Fe, Co,
Ferromagnetic metals such as Ni, Fe-Co, Co-Ni, Fe
-Co-Ni, Fe-Cu, Co-Cu, Co-Au,
Co-Pt, Fe-Cr, Co-Cr, Ni-Cr, F
e-Co-Cr, Co-Ni-Cr, Fe-Co-Ni
A ferromagnetic alloy such as -Cr may be used. The metal magnetic layer may be a single layer film or a multilayer film of these.
Further, in the case of a multilayer film, an intermediate layer may be provided in order to improve the adhesive force between the layers and control the coercive force. Also,
The vicinity of the surface of the magnetic layer may be an oxide to improve the corrosion resistance.

As a means for forming the metal magnetic layer, a vacuum evaporation method in which a ferromagnetic metal material is heated and evaporated under vacuum to be deposited on a non-magnetic support, or an ion play in which the ferromagnetic metal material is evaporated in a discharge is used. The so-called PVD technique may be used, such as a coating method, a sputtering method in which atoms on the target surface are knocked out by argon ions generated through a glow discharge in an atmosphere containing argon as a main component.

A protective film may be formed on the ferromagnetic metal material formed on the non-magnetic support,
Any material may be used as this material as long as it is used as a usual metal magnetic thin film. For example, CrO ₂ , Al ₂ O ₃ , BN, Co oxide, MgO,
_{SiO 2, Si 3 O 4,} SiNx, SiC, SiN-Si
O ₂ , ZrO ₂ , TiO ₂ , TiC and the like can be mentioned. These may be a single layer film, a multilayer film or a composite film with a metal.

As the non-magnetic support, any of those usually used as a non-magnetic support of this type of magnetic recording medium can be used. For example, polyesters, polyamides, polyolefins can be used. Examples of the support include polymer derivatives such as cellulose derivatives, vinyl resins, polyimides, polyamides, and polycarbonates.

As the binder, any binder that is usually used as a non-magnetic support of this type of magnetic recording medium can be used. For example, vinyl chloride-vinyl acetate copolymer, chloride Vinyl-propionic acid copolymer,
Examples thereof include vinyl chloride resins such as vinyl chloride vinyl acetate-vinyl alcohol copolymer, and polyurethane resins such as polyester polyurethane, polyether polyurethane, and polycarbonate polyurethane.

Of course, the structure of the magnetic recording medium according to the present invention is not limited to this, and may be changed within the scope not departing from the gist of the present invention, for example, forming a back coat layer as necessary, There is no problem in forming an undercoat layer or forming a layer of a lubricant, an anticorrosive agent or the like on the non-magnetic support. In this case, as the material contained in the non-magnetic pigment, the resin binder, the lubricant, or the rust preventive agent layer, which is contained in the back coat layer, any conventionally known material can be used.

Next, when the back coat layer is formed on the back surface of the non-magnetic support 2, the lapping tape 14 is slidably contacted in the direction perpendicular to the running direction of the non-magnetic support 2 of the first polishing device 12. The wrapping process is performed by.

That is, after the metal magnetic thin film is deposited on the non-magnetic support 2, the polishing apparatus 12 having the above-mentioned configuration is used.
Splash substances and dust that adhere to the surface of the magnetic layer of the non-magnetic support 2 during vapor deposition are removed. At this time, the spraying means 20
Therefore, compressed air may be blown.

When the removal by the first polishing device 12 is insufficient, the lapping tape 23 of the second polishing device 21 is used to wrap the nonmagnetic support 2 in the same direction as the running direction. Apply processing.

As a result, even if the magnetic recording medium is sequentially wound by the winding roll 4, the dust attached to the surface of the magnetic layer of the non-magnetic support 2 is already wound up.
It no longer adheres to the magnetic layer formed above. Therefore, as in the conventional method in which the wrapping tape is slidably contacted in the same direction as the running direction of the vapor deposition tape raw material, foreign matter or dust on the vapor deposition tape raw material attached to the wrapping tape, on the contrary, scratches the vapor deposition tape raw material. There is no such thing as putting on.

Further, by arranging the wrapping tape which is slidably contacted in the direction perpendicular to the running direction of the non-magnetic support, the foreign matter adhering to the wrapping tape or the like is arranged in the longitudinal direction of the vapor deposition tape as in the conventional method. There is no longer a chance that it will hurt you for a long time.

In the present embodiment, the non-magnetic support 2
Although the description has been given by using the configuration in which the surface of the magnetic layer is subjected to the lapping treatment, the present invention is not limited to the above-mentioned embodiment, and for example, the surface of the non-magnetic support 2 may be subjected to the lapping treatment. Alternatively, both surfaces of the surface of the non-magnetic support 2 and the surface of the magnetic layer may be subjected to lapping treatment.

Experiment The inventors of the present invention manufactured the magnetic recording medium shown in Table 1 by using the above magnetic recording medium manufacturing apparatus.

[0053]

[Table 1]

In the process of manufacturing this magnetic recording medium, the lapping process is performed by the above-described manufacturing apparatus by various methods described below, and the scratches and dropout amount (number / piece / Min) was measured.

Here, the dropout was measured by using a modified EV-S900 manufactured by Sony, and the dropout of the output under the conditions shown in Table 2 from the reproduction output level was taken as the dropout.
Minute measurement was performed to determine the number of dropouts per minute.

Further, the presence or absence of scratches was confirmed by visually inspecting the surface of the raw material vapor-deposited tape before cutting over a total length of 3000 m. Then, the size of the scratches at this time was classified into those having a length of 1 m or more and those having a length of less than 1 m.

The wrapping tape used in the experiment was prepared by mixing a polyene ethylene terephthalate (PET) base having a thickness of 15 μm as a non-magnetic support and mixing aluminum oxide particles having an average particle diameter of 3 μm with a urethane binder to obtain 5 μm.
It was manufactured with a coating thickness of. In addition to aluminum oxide, carbon, zirconium oxide, chromium oxide, SiO _{2 and the} like can be used as the abrasive particles.

[0058] As Example 1 Example 1, the feed rate of the vapor deposition tape raw is 150
/ Min, and the feeding speed of the wrapping tape 14 is 0.
It was performed under the condition of 2 m / min. Then, a top coat was applied to the surface of the magnetic layer and cut into a predetermined tape width to prepare the tape of Example 1. In order to confirm the effect in the case of this Example 1, the surface of the magnetic layer after the surface treatment was visually observed to confirm the occurrence of scratches. Table 2 shows the results.
In the first embodiment, the spraying by the spraying means 20 and the lapping process by the second polishing device 21 are not performed.

[0059]

[Table 2]

[0060] As Example 2 Example 2, when the lapping process of Example 1,
In order to further improve the adhesion to the vapor-deposited tape original fabric, compressed air is blown from the back surface of the wrapping tape 14 by the blowing means 20 to perform a lapping process so as to have a more lapping effect, and the tape of Example 2 is obtained. It was made.

As in Example 1, the feed rate of the vapor deposition tape stock was 150 / min, and the feed rate of the wrapping tape was 0.2 m / min. Then, in order to confirm the effect of Example 2, the surface of the magnetic layer after the surface treatment was visually observed to confirm the occurrence of scratches. Table 2 shows the results. In the second embodiment, the lapping process by the second polishing device 21 is not performed.

Example 3 After performing the same lapping process under the same conditions as in Example 1,
By the second polishing device 21 arranged in a so-called in-line manner, the lapping tape 14 was slid on the lapping tape 14 in the same direction as the running direction of the vapor deposition tape stock, and the lapping treatment was performed.

Comparative Example 1 As Comparative Example 1, Comparative Example 1 was prepared by lapping by a conventional method in which a lapping tape was slidably contacted in the same direction as the running direction of the vapor deposition tape stock. That is, in this apparatus, Comparative Example 1 was obtained by performing only the lapping treatment by the second polishing apparatus. The lapping process in this case was performed along the growth direction of the columnar structure of the magnetic layer.

The feed rate of the vapor-deposited tape stock was 150 / min as in Example 1, and the wrapping tape 14 was used.
The feed rate was 0.2 m / min. Then, in order to confirm the effect, the surface of the magnetic layer after the surface treatment was visually observed to confirm the occurrence of scratches.

After that, a top coat was applied to the surface of the magnetic layer and the tape was cut into a predetermined tape width to prepare Comparative Tape 1. Table 2 shows the results.

Comparative Example 2 As Comparative Example Tape 2, a tape of Comparative Example 2 which was not subjected to the lapping process was prepared.

Examination of Experimental Results First, as is apparent from Table 2, only the second polishing device 21 was used to slide the wrapping tape in the same direction as the conventional running method of the vapor deposition tape stock. In Comparative Example 1 in which only the lapping process was performed, as compared with Comparative Example 2 in which the lapping process was not performed, −10 dB and 3 μsec, −10 dB.
The effect of reducing a relatively small dropout such as 10 μsec is great. However, the effect of reducing a large dropout due to a scratch such as −16 dB10 μsec is as small as about 1/2.

Further, in Comparative Example 1, scratches are generated due to the lapping treatment, and there are advantages and disadvantages even if the conventional lapping treatment is performed under relatively good conditions. In this case, the error rate requirement required for a high-density recording system such as a consumer digital VTR currently in practical use is still insufficient.

On the other hand, according to Example 1, the occurrence of scratches was significantly better than that of Comparative Example 1. That is, it can be seen that the scratches of Example 1 are greatly reduced in both scratches having a length of 1 m or more and those having a length of less than 1 m, as compared with Comparative Example 1.

For dropout, -10
Relatively small dropouts such as dB3 μsec and −10 dB10 μsec are similar to or better than those in Comparative Example 1, and large dropouts such as −16 dB10 μsec are significantly better than Comparative Example 1. It was

Then, in Example 2 in which compressed air is blown from the back surface of the wrapping tape 14 and Example 3 in which the conventional method is combined, the effect is greater than in the case of Example 1. Recognize.

Therefore, it can be understood that the device of the present embodiment can reduce the dropout of the metal thin film magnetic recording medium and effectively prevent the generation of scratches due to the surface treatment. And Example 1
According to 3 to 3, the requirement of the error rate required for the high density recording system such as the digital VTR for consumer use which is currently put into practical use is satisfied.

[0073]

According to the method of manufacturing a magnetic recording medium of the present invention, since the lapping tape which is in sliding contact with the non-magnetic support in the direction perpendicular to the running direction is arranged, the surface treatment of the ferromagnetic metal thin film magnetic recording medium is performed. As in the conventional method in which the wrapping tape is slid only in the same direction as the running direction of the vapor deposition tape fabric, foreign matter or dust on the vapor deposition tape fabric that adheres to the wrapping tape, on the contrary, does not There will be no damage to the material.

Further, by disposing the wrapping tape which is slidably contacting in the direction perpendicular to the running direction of the non-magnetic support, the foreign matter adhered to the wrapping tape or the like is arranged in the longitudinal direction of the vapor deposition tape as in the conventional method. It will not hurt you for a long time.

Therefore, according to the method of the present invention, it is possible to reduce the dropout of the metal thin film magnetic recording medium and effectively prevent the occurrence of scratches due to the surface treatment with a simple structure.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a magnetic recording medium manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of a polishing device of the manufacturing apparatus.

[Explanation of symbols]

 2 Non-Magnetic Support (Base Film) 4 Winding Roll 5 Cooling Can 12 First Polishing Device 14 Lapping Tape 20 Spraying Means 21 Second Polishing Device

Claims (4)

[Claims] 1. A method of manufacturing a magnetic recording medium in which a metal magnetic thin film is formed on a non-magnetic support by oblique vapor deposition, wherein lapping treatment is performed in a direction substantially perpendicular to the running direction of the non-magnetic support. And a method for manufacturing a magnetic recording medium. 2. The method of manufacturing a magnetic recording medium according to claim 1, wherein compressed air is blown from the back side of the wrapping tape. 3. The lapping process is performed in a direction substantially perpendicular to the running direction of the non-magnetic support, and then the lapping process is performed in the same direction as the running direction of the non-magnetic support. A method for manufacturing the magnetic recording medium described. 4. The method of manufacturing a magnetic recording medium according to claim 1, wherein the lapping process with the lapping tape is performed after the metal magnetic thin film is formed on the non-magnetic support.