JP4048643B2 - Method for manufacturing magnetic recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a method for manufacturing a magnetic recording medium to which oblique deposition is applied.InRelated.
[0002]
[Prior art]
In recent years, the recording density of magnetic tape has been rapidly increased. In this process, the magnetic tape has shifted to high-performance ones such as iron oxide tape, metal tape, and thin film magnetic tape having high coercive force and high magnetic flux density. As an application of this magnetic tape, in the field of VTR (video tape recorder), in order to achieve digitalization and high definition, a thin film magnetic tape is particularly attracting attention.
[0003]
As this thin film magnetic tape, a so-called vapor-deposited magnetic tape in which a magnetic film is formed by an oblique vapor deposition method has been put into practical use. Specifically, a pierce-type electron gun is used in a vacuum, and an electron beam emitted from the pierce-type electron gun is irradiated to a magnetic material such as Co or CoNi in the crucible, so that these Co, CoNi, etc. Manufactured by forming a magnetic film made of CoO, CoNiO, etc. on a base film such as PET, PEN, PI (polyimide), PA (aramid), etc., while melting and evaporating the magnetic material and introducing oxygen. The
[0004]
FIG. 8 is a diagram showing a general magnetic recording medium manufacturing apparatus to which oblique vapor deposition is applied,
FIG. 9 is a diagram for explaining a modified example of a shutter in a general magnetic recording medium manufacturing apparatus.
[0005]
In the general magnetic recording medium manufacturing apparatus shown in FIG. 8, a supply roll 2, a take-up roll 3, a supply-side metal guide roller 4, a take-up-side metal guide roller 5, and cooling are provided in a vacuum chamber 1. A can roll 6 is arranged. The base film 7 fed out from the supply roll 2 continuously travels along the cooling can roll 6 in the direction of the arrow in the figure, and passes along the cooling can roll 6 that is rotatable through the guide roller 4 on the supply side. Furthermore, it is wound around the winding roll 3 through the metal guide roll 5 on the winding side. At this time, a cooler (not shown) is built in the rotatable cooling can roll 6 to prevent deformation of the base film 7 due to a temperature rise during vapor deposition on the base film 7. is doing.
[0006]
A crucible 12 containing a magnetic material 11 such as Co is disposed below the cooling can roll 6. The magnetic material 11 is melted on the supply side wall of the vacuum chamber 1 to evaporate the magnetic material. For example, a pierce-type electron gun 13 is installed obliquely downward as a heater for evaporating water.
[0007]
Further, a maximum incident angle restriction mask 8 for restricting the maximum incident angle θmax of the evaporated magnetic material from the crucible 12 to the base film 7, and a minimum incident angle of the evaporated magnetic material from the crucible 12 to the base film 7. A minimum incident angle regulating mask 9 that regulates θmin is fixedly attached along the cooling can roll 6, and the maximum incident angle regulating mask 8 provided on the upstream side along the cooling can roll 6 and the cooling can roll. Along with the minimum incident angle restriction mask 9 provided on the downstream side along the roll 6, the mask 10 is attached at a predetermined distance, and the shutter 10 is used to open and close the opening formed between the masks 8 and 9. 8 and 9 are provided so as to be movable.
[0008]
When the base film 7 is traveling along the cooling can roll 6, if the shutter 10 is moved in the direction of the arrow to open between the masks 8 and 9, the electron beam 14 from the pierce-type electron gun 13 is obtained. As a result, the magnetic material 11 in the crucible 12 melts and evaporates, and the evaporated magnetic material adheres to the base film 7 from the opening formed between the masks 8 and 9. A magnetic film is deposited. At this time, the magnetic film is generally formed on the base film 7 with the maximum incident angle θmax = 90 ° and the minimum incident angle θmin = 40 °.
[0009]
The electron beam 14 from the pierce-type electron gun 13 is controlled by a deflection magnet 15 attached to the pierce-type electron gun 13 and a deflection magnet installed near the crucible 12 and applying a deflection magnetic field in the trajectory of the electron beam 14. This is performed by the magnet 16. The irradiation position of the electron beam 14 is scanned at a predetermined period in the width direction of the base film 7 at the center of the crucible 12, and the magnetic material 11 in the crucible 12 is dissolved and evaporated.
[0010]
Further, the shutter 10 shields the region of the mouth formed between the minimum incident angle θmin and the maximum incident angle θmax until the temperature of the magnetic material 11 in the crucible 12 reaches a predetermined state, so that the predetermined temperature state is obtained. When the vapor deposition is possible, the shutter 10 moves in the direction of the arrow, and a magnetic film is deposited on the base film 7 with a predetermined thickness. The shutter 10 described above is of the type that moves along the cooling can roll 6 in FIG. 8, but as shown in FIG. 9, a shutter 17 is installed above the crucible 12 so as to be horizontally movable. A method of blocking the material may be used.
[0011]
[Problems to be solved by the invention]
By the way, in the above-described general magnetic recording medium manufacturing apparatus, when the magnetic material 11 in the crucible 12 reaches a predetermined temperature state and the shutter 10 is opened, the following problems occur.
[0012]
That is, when the electron beam 14 is irradiated onto a magnetic material such as Co, a large amount of secondary electrons (backscattered electrons) are generated and reach the base film 7 through the opening between the masks 8 and 9. The secondary electrons are charged on the surface of the base film 7, and the base film 7 comes into close contact with the cooling can roll 6 by electrostatic force. This adhesion force increases as the area of the opening between the masks 8 and 9 increases. For this reason, when the shutter 10 is opened, the adhesion force changes suddenly in the film running direction and becomes non-uniform, which causes generation of wrinkles on the base film 7. The base film 7 is heated by radiant heat from the melted magnetic material 11, heat of condensation when the evaporated magnetic material becomes a thin magnetic film on the base film 7, and heat from reaching secondary electrons. At this time, the base film 7 is cooled by the cooling can roll 6, but the temperature of the base film 7 rises when the shutter 10 is opened within the range of the heat resistance temperature of the base film 7, and the temperature rises when the opening area is widened. Becomes bigger. For this reason, when the shutter 10 is opened, the film temperature changes abruptly in the film traveling direction and becomes non-uniform, which causes wrinkles on the base film 7 due to thermal contraction and thermal expansion of the base film 7. The wrinkles generated at the opening between the masks 8 and 9 continue to be generated due to the wrinkles once generated even after the shutter 10 has been moved to a predetermined state. In addition, the generation of wrinkles may be eliminated during the filming process, but the surface of the base film 7 that has already been wound has convex wrinkles, and after the generation of wrinkles at the openings, Since it is wound on the cumulative wrinkle, there is a problem that it is transferred and left as a transfer wrinkle when unwound.
[0013]
[Means for Solving the Problems]
  The present invention has been made in view of the above problems, and the first invention isA supply roll that feeds out the base film, a cooling can roll that travels the base film fed from the supply roll along the circumference, and a base film that travels on the cooling can roll while being kept at ground potential. A metal guide roll, a winding roll that winds up the base film that has traveled the metal guide roll, and a traveling direction of the base film of the cooling can roll, and has a predetermined distance from the cooling can roll. The opening area of the opening formed between the first incident angle restricting mask and the second incident angle restricting mask which are sequentially arranged, and the first and second incident angle restricting masks provided along the cooling can roll. An apparatus for manufacturing a magnetic recording medium, comprising: a shutter for adjusting the magnetic field; and an electron gun for melting a magnetic material housed in the crucible. There, theSent from the supply rollSaidBase filmSaidCooling can rollCircumferenceRun alongEvaporating the magnetic material by an electron beam emitted from the electron gun;Magnetic film on the base filmAfter forming, through the metal guide rollWinding rollsoIn the method of manufacturing a magnetic recording medium to be wound,
  The magnetic film adjusts the shutter to expose a part of the opening, and evaporates the magnetic material by the electron beam on the base film to form a first film having a thickness of 100 to 800 mm. After the magnetic film is formed, the shutter is adjusted again after a lapse of time until the tip portion of the first magnetic film reaches the metal guide roll at the start of manufacturing the first magnetic film, It is obtained by forming a second magnetic film on the base film by exposing the entire opening and evaporating the magnetic material by the electron beam on the base film.A method of manufacturing a magnetic recording medium.
[0014]
  In addition, the second invention,A supply roll that feeds out the base film, a cooling can roll that travels the base film fed from the supply roll along the circumference, and a base film that travels on the cooling can roll while being kept at ground potential. A predetermined distance is provided between the metal guide roll, the winding roll that winds the base film that has traveled the metal guide roll, and the cooling can roll along the traveling direction of the base film of the cooling can roll. And a first incident angle restriction mask and a second incident angle restriction mask provided with sequentially arranged windows, and the first and second incident angle restriction masks provided along the cooling can roll. Magnetic recording device comprising a shutter for adjusting the opening area of the formed opening and an electron gun for melting the magnetic material housed in the crucible. Using the manufacturing apparatus of the medium, theSent from the supply rollSaidBase filmSaidCooling can rollCircumferenceRun alongEvaporating the magnetic material by an electron beam emitted from the electron gun;Magnetic film on the base filmAfter forming, through the metal guide rollWinding rollsoIn the method of manufacturing a magnetic recording medium to be wound,
  The magnetic film adjusts the shutter so as not to expose the opening, and evaporates the magnetic material by the electron beam on the base film exposed from the window, and has a thickness of 100 to 800 mm. The first magnetic film is formed, and after the time that the tip portion of the first magnetic film reaches the metal guide roll at the start of manufacture of the first magnetic film, the shutter is adjusted to adjust the opening. And the second magnetic film is formed on the first magnetic film by evaporating the magnetic material with the electron beam on the base film.A method of manufacturing a magnetic recording medium.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a magnetic recording medium manufacturing method and a magnetic recording medium manufacturing apparatus according to the present invention will be described in detail in the order of <first embodiment> and <second embodiment> with reference to FIGS. explain.
[0018]
<First Embodiment>
FIG. 1 is a diagram for explaining a magnetic recording medium manufacturing method according to a first embodiment and a magnetic recording medium manufacturing apparatus according to the first embodiment of the present invention, and a maximum incident angle restricting mask and a minimum incident angle restricting mask. The figure which showed the state which covered a part of opening part between with a shutter,
FIG. 2 is a view for explaining the magnetic recording medium manufacturing method according to the first embodiment and the magnetic recording medium manufacturing apparatus according to the first embodiment of the present invention. The figure which showed the state which opened completely the opening part between,
FIG. 3 is a diagram for explaining a state in which a magnetic film is formed on a base film according to Example 1 of the first embodiment by applying the magnetic recording medium manufacturing apparatus according to the first embodiment of the present invention;
FIG. 4 is a diagram showing the results of Example 1, Example 2, and Comparative Example 1.
For convenience of explanation, the same reference numerals are given to the same constituent members as those shown above.
[0019]
In the magnetic recording medium manufacturing method of the first embodiment and the magnetic recording medium manufacturing apparatus of the first embodiment according to the present invention, the general magnetic recording medium manufacturing apparatus described above is partially improved and cooled. The opening area of the opening formed between the maximum incident angle restricting mask 8 and the minimum incident angle restricting mask 9 attached along the can roll 6 is configured to be adjustable by the shutter 10, and the winding side metal The guide roller 5 is grounded.
[0020]
As shown in FIG. 1, the oblique recording method is applied to the magnetic recording medium manufacturing apparatus of the first embodiment, and the base film 7 fed from the supply roll 2 in the vacuum chamber 1 is a supply-side guide. The roller 4 is wound around the winding roll 3 through a winding roller 3 which can rotate and roll, and a metal guide roll 5 on the winding side which is grounded. The winding-side metal guide roll 5 described above is a grounding means for electrically dropping electrons charged on the surface of the magnetic film formed on the base film 7 to the ground as will be described later.
[0021]
On the other hand, in a state where oxygen is introduced into the vacuum chamber 1, the electron beam 14 from the pierce-type electron gun 13 attached to the supply side wall of the vacuum chamber 1 passes through the crucible 12 installed below the cooling can roll 6. The magnetic material 11 such as Co is dissolved, and the evaporated magnetic material is evaporated toward the cooling can roll 6.
[0022]
Further, in an opening formed between the maximum incident angle restriction mask 8 attached upstream along the cooling can roll 6 and the minimum incident angle restriction mask 9 attached downstream along the cooling can roll 6. The shutter 10 is provided so that the opening area of the opening can be adjusted.
[0023]
Next, a method of manufacturing the magnetic recording medium according to the first embodiment in which a magnetic film is formed on the base film 7 using the magnetic recording medium manufacturing apparatus according to the first embodiment configured as described above will be described. .
[0024]
First, at the start of film formation, the opening area of the opening formed between the maximum incident angle restriction mask 8 and the minimum incident angle restriction mask 9 attached along the cooling can roll 6 is set to a small opening area S. The shutter 10 is operated. Then, the base film 7 is continuously run along the cooling can roll 6 in the direction of the arrow, and during a short period immediately after the start of film formation, the evaporated magnetic material evaporated from the crucible 12 has the small opening area S. Therefore, a magnetic film thinner than a predetermined film thickness, which is the target film deposition amount, is deposited on the base film 7.
[0025]
Here, during a short period immediately after the start of film deposition, in the first embodiment to be described later, the winding-side metal guide roll in which the leading portion of the thin magnetic film deposited on the base film 7 is grounded (grounded). (Grounding means) 5 is a period of time to reach 5 and, on the other hand, in Example 2 to be described later, the winding side metal guide roll in which the leading portion of the thin magnetic film formed on the base film 7 is grounded. (Grounding means) This is a period of time before reaching 5. In Example 1 to be described later, a thin magnetic film having a thickness of 100 to 800 mm is formed on the base film 7 during a short period immediately after the start of filming. After the leading portion of the thin magnetic film formed reaches the winding-side metal guide roll (grounding means) 5 that is grounded (grounded), the surface of the thin magnetic film is charged by the winding-side metal guide roll 5. The electrons are electrically dropped to the ground, and thereafter, the surface of the magnetic film is always dropped to the ground while the base film 7 is being wound around the winding roll 3.
[0026]
On the other hand, in Example 2, which will be described later, a thin magnetic film with a thickness of 100 to 400 mm is formed on the base film 7 during a short period immediately after the start of film formation. During the period, the leading portion of the thin magnetic film formed on the base film 7 does not reach the winding-side metal guide roll (grounding means) 5 that is grounded.
[0027]
Next, in Examples 1 and 2 described later, after a lapse of a short period immediately after the start of film deposition, the shutter 10 is fully opened, as shown in FIG. Since all the openings formed between the incident angle restricting mask 9 are exposed, the magnetic film having a predetermined film thickness is normally formed on the base film 7 by the evaporated magnetic material that has passed through the fully opened openings. It is filmed.
[0028]
Thereafter, in Examples 1 and 2 to be described later, the surface of the magnetic film formed with a predetermined film thickness on the base film 7 is dropped to the ground by the metal guide roll 5 on the winding side.
[0029]
Example 1
1 and 2, a PET film (base film) 6 having a length of 10000 m, a width of 300 mm, and a thickness of 6 μm is introduced while introducing oxygen using a cooling can roll 6 having a diameter of 1000 mm. The film was continuously run along the cooling can roll 6 at 50 m / min, and a CoO film (magnetic film) was formed to a predetermined film thickness of approximately 0.2 μm while introducing oxygen. At this time, a film of about 0.2 μm is not immediately formed from the time of opening of the shutter 10 as in the prior art, and the film thickness of the CoO film is less than a predetermined film thickness XÅ at a film traveling speed of 50 m / min. As shown in FIG. 1, the shutter 10 was stopped halfway without being fully opened, and the film thickness of the magnetic film was adjusted by the opening area S of the opening. That is, in the first embodiment, a period in which the leading portion of the thin magnetic film formed on the base film 7 reaches the winding-side metal guide roll 5 that is grounded (grounded) is a period immediately after the start of film formation. A short period is set.
[0030]
At this time, the evaporation speed of the CoO film is a speed at which the CoO film is formed to be approximately 0.2 μm under the condition that the shutter 10 is fully opened and the film traveling speed is 50 m / min. The film thickness of the CoO film having a thin film thickness XÅ is separated from the cooling can roll 6, and the leading portion of the thin CoO film on the PET film 7 is achieved by the metal guide roller 5 on the winding side. This was done until the surface electrically fell to ground. Thereafter, the shutter 10 was fully opened as shown in FIG. 2, and a CoO film having a thickness of about 0.2 μm was formed to 9000 m. In addition, the incident angle of the evaporated magnetic material when forming the CoO film of about 0.2 μm is 90 ° for the initial maximum incident angle and 40 ° for the minimum incident angle.
[0031]
  Here, in a short period of time immediately after the start of film formation, a thin film thickness XÅ when a CoO film thinner than a predetermined film thickness is formed on the base film 7 is 100 mm, 200 mm, 400 mm, 600 mm, 800 mm, 1000 mm.soFilming was performed.
[0032]
When the film application state of Example 1 is shown in FIG. 3, a magnetic film thinner than a predetermined film thickness is formed on the base film 7 in a short period immediately after the start of film application. The magnetic film is formed on the base film 7 with a predetermined film thickness.
[0033]
(Example 2)
In Example 1, the shutter 10 is fully opened before the leading portion of the initial CoO film deposited with a thin film thickness is electrically dropped to the ground by the metal guide roller 5 on the winding side, and the CoO of about 0.2 μm is formed. The film was formed under the same conditions except that a film of 9000 m was formed. That is, in the second embodiment, during the period in which the leading portion of the thin magnetic film formed on the base film 7 reaches before the metal guide roll 5 on the winding side that is grounded (grounded), the film formation starts. It is set for a short period immediately after.
[0034]
(Comparative Example 1)
The same procedure as in Example 1 was performed except that the shutter 10 was fully opened from the start of film formation and a CoO film of approximately 0.2 μm was formed to 9000 m.
[0035]
The results of Examples 1 and 2 and Comparative Example 1 are shown in FIG. As apparent from FIG. 4, wrinkles occur in Comparative Example 1, but in Example 1, when the initial CoO film thickness is 100 to 800 mm, the wrinkles are generated when the shutter 10 is partially opened and when the shutter 10 is fully opened. Has not occurred. That is, when the leading portion of the thin magnetic film on the PET film 7 from Example 1 passes through the metal guide roll 5 on the winding side, the charge amount at the opening is reduced by dropping the surface of the thin magnetic film to the ground. Wrinkles are generated due to the abrupt change in the adhesion of the PET film 7 to the cooling can roll 6 and the temperature of the PET film 7 in the film running direction when the shutter 10 is fully opened during film formation. It turns out that it becomes difficult to do. From the above, in Example 1, the shutter 10 may be adjusted to the opening area S of the opening so that the initial thickness of the CoO film is 100 to 800 mm.
[0036]
  In Example 2, when the initial thickness of the CoO film is 100 to 400 mm, no wrinkle is generated when the shutter 10 is partially opened and when the shutter 10 is fully opened.ThisIn Example 2, although the leading portion of the thin magnetic film formed on the PET film 7 does not reach the winding-side metal guide roll 5 during a short period immediately after the start of film formation, the metal magnetic film is formed on the film. Therefore, the Young's modulus is high, and when the shutter 10 is fully opened, the rapid temperature rise of the PET film 7 can be suppressed, and the unevenness of temperature is alleviated. Occurrence can be prevented.
[0037]
  When the initial film thickness is up to 800 mm, wrinkles are not generated due to the temperature increase of the PET film 7 or unevenness in the running direction of the adhesion due to charging.NoHowever, since wrinkles are generated at 1000 mm, at 800 mm, when the shutter 10 is fully opened immediately after film formation and 0.2 μm film is formed, there is a severe situation regarding the generation of wrinkles.
[0038]
In Example 1, since the shutter 10 is fully opened and the film is deposited to a thickness of 0.2 μm, it falls to the ground, so the amount of charge can be reduced. Even when the initial film thickness is 800 mm, wrinkle generation is severe. No wrinkles were generated when 0.2 μm film was applied.
[0039]
In Example 2, when the shutter 10 is fully opened and 0.2 μm is deposited, it does not fall to the ground, so the amount of charge unevenness increases, and when the initial film thickness is 800 mm, the situation is severe with respect to wrinkles. Therefore, wrinkles are generated when a 0.2 μm film is formed. Wrinkles are similarly generated even at an initial film thickness of 600 mm, and when the initial film thickness is 400 mm, there is a margin for the generation of wrinkles when the shutter is fully opened immediately after the initial film formation, so no wrinkles are generated when a 0.2 μm film is formed. .
[0040]
Second Embodiment
FIG. 5 is a view for explaining the magnetic recording medium manufacturing method according to the second embodiment and the magnetic recording medium manufacturing apparatus according to the second embodiment of the present invention. The figure which formed the state and showed the state which closed the shutter,
FIG. 6 is a view for explaining the magnetic recording medium manufacturing method according to the second embodiment and the magnetic recording medium manufacturing apparatus according to the second embodiment of the present invention. The figure which formed the state and showed the state which opened the shutter,
FIG. 7 is a diagram for explaining a state in which a magnetic film is formed on a base film according to Example 1 of the second embodiment by applying the magnetic recording medium manufacturing apparatus of the second embodiment according to the present invention. is there.
For convenience of explanation, the same reference numerals are given to the same constituent members as those shown above.
[0041]
In the magnetic recording medium manufacturing method of the second embodiment and the magnetic recording medium manufacturing apparatus of the second embodiment according to the present invention, the general magnetic recording medium manufacturing apparatus described above is partially improved and cooled. A window 8a is formed by slightly opening a portion below the maximum incident angle restriction mask 8 attached upstream along the can roll 6, and the metal guide roller 5 on the winding side is grounded (earth). is doing.
[0042]
As shown in FIG. 5, the oblique vapor deposition method is also applied to the magnetic recording medium manufacturing apparatus of the second embodiment, and the base film 7 fed from the supply roll 2 in the vacuum chamber 1 is the supply side guide. The roller 4 is wound around the winding roll 3 through a winding roller 3 which can rotate and roll, and a metal guide roll 5 on the winding side which is grounded.
[0043]
On the other hand, the electron beam 14 from the pierce-type electron gun 13 attached to the supply side wall of the vacuum chamber 1 dissolves the magnetic material 11 such as Co in the crucible 12 installed below the cooling can roll 6 to evaporate magnetism. The material is evaporated toward the cooling can roll 6.
[0044]
Of the evaporated magnetic material evaporated in the crucible 12, the window 8 a is formed by slightly opening a part below the maximum incident angle restriction mask 8 attached upstream along the cooling can roll 6. A part of the magnetic film enters the window portion 8a, and the magnetic film can be deposited on the base film 7 with a film thickness smaller than a predetermined film thickness by the evaporated magnetic material.
[0045]
Next, a method for manufacturing a magnetic recording medium according to the second embodiment in which a magnetic film is formed on the base film 7 using the magnetic recording medium manufacturing apparatus according to the second embodiment configured as described above will be described. .
[0046]
First, as shown in FIG. 5, the opening formed between the maximum incident angle restriction mask 8 and the minimum incident angle restriction mask 9 attached along the cooling can roll 6 at the start of film formation is closed by the shutter 10. The evaporative magnetic material wraps around from the window portion 8a of the maximum incident angle regulating mask 8 installed on the upstream side of the cooling can roll 6 while continuously moving the base film 7 along the cooling can roll 6 in the direction of the arrow. In a short period immediately after the start of film deposition, the magnetic film is first deposited on the base film 7 with a film thickness smaller than a predetermined film thickness by the evaporated magnetic material.
[0047]
Here, when describing the first and second embodiments corresponding to the first and second embodiments described above with respect to the first and second embodiments, as in the first embodiment, immediately after the start of film deposition. During a short period of time, in Example 1 of the second embodiment, the winding-side metal guide roll (grounding means) in which the leading portion of the thin magnetic film formed on the base film 7 is grounded (grounded) On the other hand, in Example 2 of the second embodiment, on the winding side metal guide roll (the ground portion of the thin magnetic film formed on the base film 7 is grounded) This is a period of time before reaching the grounding means 5.
[0048]
In Example 1, a thin magnetic film having a thickness of 100 to 800 mm is formed on the base film 7 during a short period immediately after the start of film formation, and the film is formed on the base film 7. After the leading portion of the thin magnetic film reaches the winding-side metal guide roll (grounding means) 5 that is grounded (grounded), electrons charged on the surface of the thin magnetic film by the winding-side metal guide roll 5 The surface of the magnetic film is dropped to the ground while the base film 7 is always wound around the winding roll 3.
[0049]
On the other hand, in Example 2, a thin magnetic film with a film thickness of 100 to 400 mm was formed on the base film 7 during a short period immediately after the start of film formation, and during a short period immediately after the start of film formation. Then, the leading portion of the thin magnetic film formed on the base film 7 does not reach the winding-side metal guide roll (grounding means) 5 that is grounded.
[0050]
Next, in Examples 1 and 2 described above, after a short period immediately after the start of film deposition, as shown in FIG. 6, the shutter 10 is fully opened, and the maximum incident angle restriction mask 8 and the minimum All the openings formed between the incident angle restriction mask 9 are exposed and the window 8a of the maximum incident angle restriction mask 8 is open, so that the evaporation that has passed through the opening formed downstream from the window 8a. A magnetic film is further formed on the thin magnetic film on the base film 7 by a magnetic material as usual with a predetermined film thickness. Thereafter, the surface of the magnetic film formed with a predetermined film thickness on the base film 7 is dropped to the ground by the metal guide roll 5 on the winding side.
[0051]
FIG. 7 shows the state of film formation in Example 1 described above. A magnetic film thinner than a predetermined film thickness is formed on the base film 7 in a short period immediately after the start of film formation. When the leading portion of the thin magnetic film on the film 7 passes through the metal guide roll 5 on the winding side, the charge amount at the opening is reduced by electrically dropping the surface of the thin magnetic film to the ground. The film is wrinkled against a rapid change in the adhesion force of the base film 7 to the cooling can roll 6 and the temperature of the base film 7 when the shutter 10 is fully opened during film formation. Less likely to occur.
[0052]
On the other hand, in Example 2, although the leading portion of the thin magnetic film formed on the base film 7 does not reach the winding-side metal guide roll 5 during a short period immediately after the start of film formation, the metal magnetic film Since the film is attached, the Young's modulus is high, and when the shutter 10 is fully opened, the rapid temperature rise of the base film 7 can be suppressed and the unevenness of temperature is alleviated. -Generation | occurrence | production of the wrinkle of the film 7 can be prevented.
[0053]
In other words, in Examples 1 and 2, the magnetic film is deposited on the base film 7 on the upstream side of the cooling can roll 6 in a short period immediately after the start of film deposition, with a film thickness smaller than a predetermined film thickness, and After a short period immediately after the start of film formation, a predetermined film is further formed on the magnetic film formed on the base film 7 with a thin film thickness on the downstream side below the upstream side of the cooling can roll 6. It is coated with a thickness.
[0054]
The results of Examples 1 and 2 of the second embodiment are similar to the results of Examples 1 and 2 of the first embodiment described with reference to FIG. Omitted.
[0055]
At this time, the window portion 8a of the maximum incident angle restricting mask 8 is set so that the initial magnetic film thickness is 100 to 800 mm in Example 1 and the initial magnetic film thickness is 100 to 400 mm in Example 2. What is necessary is just to form.
[0056]
【The invention's effect】
  According to the present invention, the method of manufacturing the magnetic recording medium according to the present invention described in detail above.InClaim1according to,The second magnetic film is formed after a lapse of time until the tip portion of the first magnetic film reaches the grounded metal guide roll at the start of manufacturing the first magnetic film having a thickness of 100 to 800 mm. Because you getCan reduce the amount of charge on the magnetic filmBecauseBase fillMuAdhesive strength to the cooling can roll and base fillMuThus, wrinkles are less likely to occur due to a sudden change in temperature, and the yield of magnetic recording media can be improved.
[0057]
  Further claims2according to,While the first magnetic film having a thickness of 100 to 800 mm is formed as the magnetic film, the time elapses until the tip portion of the first magnetic film reaches the metal guide roll at the start of manufacturing the first magnetic film. Since the second magnetic film is formed on the first magnetic film later,Similar effectcan get.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram for explaining a magnetic recording medium manufacturing method according to a first embodiment and a magnetic recording medium manufacturing apparatus according to the first embodiment of the present invention. It is the figure which showed the state which partially covered the opening part between masks with the shutter.
FIGS. 2A and 2B are diagrams for explaining the magnetic recording medium manufacturing method according to the first embodiment and the magnetic recording medium manufacturing apparatus according to the first embodiment, and are a maximum incident angle restriction mask and a minimum incident angle restriction; FIGS. It is the figure which showed the state which opened the opening part between masks completely.
FIG. 3 is a diagram for explaining a state in which a magnetic film is formed on a base film according to Example 1 of the first embodiment by applying the magnetic recording medium manufacturing apparatus of the first embodiment according to the present invention. It is.
4 is a graph showing the results of Example 1, Example 2, and Comparative Example 1. FIG.
FIG. 5 is a view for explaining a magnetic recording medium manufacturing method according to a second embodiment and a magnetic recording medium manufacturing apparatus according to the second embodiment of the present invention. It is the figure which showed the state which formed the part and closed the shutter.
FIG. 6 is a view for explaining a magnetic recording medium manufacturing method according to a second embodiment and a magnetic recording medium manufacturing apparatus according to the second embodiment of the present invention; It is the figure which showed the state which formed the part and opened the shutter.
FIG. 7 is a diagram for explaining a state in which a magnetic film is formed on a base film according to Example 1 of the second embodiment by applying the magnetic recording medium manufacturing apparatus of the second embodiment according to the present invention. It is.
FIG. 8 is a diagram showing a general magnetic recording medium manufacturing apparatus to which oblique vapor deposition is applied.
FIG. 9 is a diagram for explaining a modified example of a shutter in a general magnetic recording medium manufacturing apparatus.
[Explanation of symbols]
1 ... Vacuum tank, 2 ... Supply roll, 3 ... Winding roll,
4 ... Guide roller on the supply side, 5 ... Guide roller on the take-up side (grounding means),
6 ... Cooling can roll, 7 ... Base film (PET film),
8 ... Maximum incident angle regulating mask, 8a ... Window, 9 ... Minimum incident angle regulating mask,
10 ... shutter, 11 ... magnetic material, 12 ... crucible,
13 ... Piercing electron gun.

Claims (2)

A supply roll that feeds out the base film, a cooling can roll that travels the base film fed from the supply roll along the circumference, and a base film that travels on the cooling can roll while being kept at ground potential. A metal guide roll, a winding roll that winds up the base film that has traveled the metal guide roll, and a traveling direction of the base film of the cooling can roll, and has a predetermined distance from the cooling can roll. The opening area of the opening formed between the first incident angle restricting mask and the second incident angle restricting mask which are sequentially arranged, and the first and second incident angle restricting masks provided along the cooling can roll. An apparatus for manufacturing a magnetic recording medium, comprising: a shutter for adjusting the magnetic field; and an electron gun for melting a magnetic material housed in the crucible. There, the base film fed from the supply roll to run along the circumference of the cooling can roll, wherein evaporated the magnetic material by the electron beam emitted from an electron gun, a magnetic layer on the base film After forming, in the method for manufacturing a magnetic recording medium wound up by the winding roll through the metal guide roll ,
The magnetic film is
The shutter was adjusted to expose a part of the opening, and the magnetic material was evaporated by the electron beam on the base film to form a first magnetic film having a thickness of 100 mm to 800 mm. Thereafter, after the elapse of time until the tip portion of the first magnetic film reaches the metal guide roll at the start of manufacture of the first magnetic film, the shutter is adjusted again so that the entire opening is the state of being exposed, said by electron beam evaporation of the magnetic material to the base film, manufacturing a magnetic recording medium characterized Rukoto obtained by forming a second magnetic layer on the base film Method. A supply roll that feeds out the base film, a cooling can roll that travels the base film fed from the supply roll along the circumference, and a base film that travels on the cooling can roll while being kept at ground potential. A predetermined distance is provided between the metal guide roll, the winding roll that winds the base film that has traveled the metal guide roll, and the cooling can roll along the traveling direction of the base film of the cooling can roll. And a first incident angle restriction mask and a second incident angle restriction mask provided with sequentially arranged windows, and the first and second incident angle restriction masks provided along the cooling can roll. Magnetic recording device comprising a shutter for adjusting the opening area of the formed opening and an electron gun for melting the magnetic material housed in the crucible. Using the manufacturing apparatus of the medium, the base film fed from the supply roll to run along the circumference of the cooling can roll, evaporate the magnetic material by the electron beam emitted from the electron gun, the base film In the method of manufacturing a magnetic recording medium, after forming a magnetic film on the winding film, the winding roll is wound through the metal guide roll .
The magnetic film is
The shutter is adjusted so that the opening is not exposed, and the magnetic material is evaporated by the electron beam on the base film exposed from the window, so that a first magnetic film having a thickness of 100 to 800 mm is obtained. After the elapse of time when the tip portion of the first magnetic film reaches the metal guide roll at the start of manufacturing the first magnetic film, the shutter is adjusted to expose all the openings. and the state, said base film by the electron beam on the evaporation of the magnetic material, the magnetic recording medium characterized obtain isosamples forming a second magnetic layer on the first magnetic layer Production method.

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