JPH04159954A - Method and device for handling web of thin film magnetic recording medium - Google Patents

Abstract

PURPOSE:To prevent the wrinkling of a web under running even under a low tension without using any complicated device by forming a running passage into S-shape by the outer circumference of a roll pair at the time of continuous running of a web, bending the web by the upper stream side roll so as to be pulled to both lateral end sides, and guiding the web by the other roll so as to restore the bending. CONSTITUTION:As the axial sectional form of a crown roll 2 is properly curved so that the roll cross directional center diameter is large and the diameter on both end sides is small, a web 5 in contact with the outer circumference of the roll 2 receives a force as being slightly stretched in the web cross direction according to the curvature of the roll outer circumference. Therefore, when the web 5 takes a motion as shifting from the center line of a route, a force as returning this shift is generated to regulate the movement in the web direction from a slight tension added to the web, and a centering effect as regularly positioning the web on the running center line is worked. Thus, the wrinkling of the web under running can be effectively prevented even under a low tension without using any complicated device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for web handling of a thin film magnetic recording medium, and in particular to a web handling method and apparatus for a thin film magnetic recording medium, in particular by sputtering, vapor deposition, etc.
The present invention relates to a web handling method and apparatus for running and conveying a web made of a polymeric material.

[Conventional technology]

Generally, in magnetic recording media, a thin and flexible support (web) is often used as the support for forming the magnetic layer. This web is generally made of a polymeric material such as polyethylene terephthalate, and is fed out as a raw material wound into a roll, and is subjected to appropriate processing such as pre-surface treatment, formation of a magnetic film, and post-surface treatment during its running. A method of rewinding is often used.

Since the web processed by this method has an extremely thin thickness, the web tends to wrinkle or curl during processing.

Conventionally, a common method is to provide an expander roll to prevent wrinkles and wrinkles in the web. Further, Japanese Patent Application Laid-Open No. 55-4494 discloses a method of conveying a web in which the edge portion of the web is prevented from being damaged by a roll having a tapered end portion. Unexamined Japanese Patent Publication No. 1-
In Japanese Patent No. 165031, a roll having a small diameter with a concave center portion guides the web running, and when the web comes into contact with a large diameter drum, the web is wrinkled on the drum by passing through the concave roll. This is a method to prevent this.

In this way, the reason for preventing wrinkles in the web is that, for example, if there are wrinkles during the formation of the magnetic layer, the layer formed on the wrinkles will have a reduced thickness due to the wrinkles. When irregularities are formed and wrinkles are stretched, the magnetic layer may become distorted, or in severe cases, the magnetic layer may become damaged or defective, causing serious problems in terms of the quality of the magnetic recording medium. Furthermore, if a surface treatment such as oxidation treatment is applied to the magnetic layer on the web after it has been formed, the magnetic layer becomes hard, and in particular, if wrinkles or kinks occur while the web is running, the magnetic layer may become fine. web transport is extremely important to ensure product quality.

One of the current magnetic recording media that has excellent recording properties is, for example, a vapor-deposited metal thin film tape. Manufacturing techniques for improving the quality of this vapor deposition tape include oxidation treatment and ozone treatment of the vapor deposition surface. In these processing steps, the transport system members (rolls) that can be used are:
For example, 5US-316 that can withstand the processing process.
, Teflon, etc., and the materials used are extremely limited. Further, members made of these materials have poor workability and are not suitable for connection to a tension control device that requires a complicated drive connection structure.

Therefore, in the case of the above-mentioned expander roll, a drive system is also required, and due to its structure, there is a problem in durability against the ozone layer, making it extremely difficult to use.

Furthermore, in the method disclosed in Japanese Patent Application Laid-open No. 55-4494, the transport roll is tapered at the end portion of the web, which is relatively easily damaged, so that the load during web travel is not applied to the end portion of the web. This is a mitigation measure. However, it was incomplete as a countermeasure against wrinkles and deformation across the entire width of the web.

Furthermore, in the method disclosed in Japanese Patent Application Laid-Open No. 1-165031, when the web is fed to a drum that processes the web,
An attempt was made to prevent wrinkles from forming on the web by installing a concave roll that contacts the tram from the center of the web. This configuration is a structure for feeding the web to the drum, and is insufficient as a measure for the overall conveyance of the web.

In particular, as mentioned above, the material that can be used as a roll is generally difficult to process, and in addition, if the web is processed in such a way that high tension cannot be applied, the above-mentioned warping and Countermeasures against wrinkles are insufficient, there are still many unresolved technologies, and the product yield is low.

[Invention or problem to be solved]

An object of the present invention is to provide a web handling method and apparatus for a thin film magnetic recording medium that can effectively prevent wrinkles from occurring in a running web even under low tension without using a complicated device. It is in.

[Means to solve the problem]

The problem related to the present invention is that when a web of a thin film magnetic recording medium is continuously run, the web is made to have a substantially S-shaped running path by the outer circumference of a pair of rolls constituting the web transport path, and the roll A thin film magnetic recording medium characterized in that an upstream roll causes the web to be warped in the web width direction so as to pull it toward both ends in the width direction, and the other roll guides the web so as to return the warpage in the web width direction. This can be solved by the web handling method.

Further, a similar problem of the present invention is to provide an apparatus for continuously running a web of a thin film magnetic recording medium, in which the web is wound around a crown roll constituting a web conveyance path, and
The web is wound around a guide roll that is disposed close to the crown roll and has a constant outer diameter along the roller radius direction, so that the running path of the web is approximately S-shaped between the crown roll and the guide roll. The present invention is solved by a web handling device for a thin film magnetic recording medium, which is characterized by:

[Embodiment]

Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to this embodiment.

FIG. 1 shows a part of the process of manufacturing a magnetic tape, in which a web 5 on which cobalt-nickel (Co--Ni) is vacuum-deposited, for example, is surface-treated with oxygen and ozone.

The web 5, on which the Co--Ni0 layer has been formed, is subjected to surface treatment using oxygen and ozone in the vapor deposition surface modification zone 6. Naturally, the surface treatment in the vapor deposition surface modification zone 6 is performed while the web 5 is not continuously running. Therefore, the surface-treated web 5 is finally wound up by the winder 4, or just before the winder 4, the crown roll 2 and the guide roll 3 (in this case, a contact roll) are arranged close together. That is, the web 5 is held so as to be wrapped around the crown roll 2 at a certain angle, and the guide roll 3 is configured to contact the winder 4 while maintaining the winding angle around the crown roll 2. An S-shaped traveling unit 1 is provided.

As shown in FIG. 2, the crown roll 2 has a cross section along its axial direction or an appropriate curved line having the largest diameter at its center and gradually decreasing in diameter toward both left and right ends. Moreover, unlike the crown roll 2, the guide roll 3 has a structure in which the outer diameter is constant across the width direction of the roller.

The S-type traveling unit 1 produces the following effects.

As mentioned above, the crown roll 2 has a cross-sectional shape in the axial direction or an appropriately curved configuration such that the large diameter is at the center in the roll width direction and the small diameter is at both ends. The web 5 in contact with the web 5 is subjected to a force such that it is stretched very slightly in the width direction of the web in response to the curved surface of the outer periphery of the roll. Due to the action of such force,
When the web 5 moves so as to deviate from the center line of its original path, it effectively generates a force that tries to return the deviation in the width direction, and reduces the slight force applied to the web itself. A so-called centering action works by effectively adjusting the movement from the tension in the width direction of the web to always keep the web at the running center line.

This centering action occurs extremely effectively because the guide roll 3, which has a constant diameter across the width, is provided at a position close to the crown roll 2.

That is, the web 5 in contact with the outer peripheral surface of the crown roll 2 is returned to a flat state at the outer peripheral surface of the guide roll 3. It is possible to cause a change in the web width direction from a curved state to a flat state while the web is running, or to cause a subtle change in the internal stress of the web 5.

Therefore, due to the change in the internal stress generated in the web 5, a balanced tension is generated in the width direction of the web 5, which effectively prevents the occurrence of wrinkles in the web 5 as well as the above-mentioned alignment effect. It is presumed that it is possible to do so.

The winding angle of the web 5 on the crown roll 2 and the winding angle of the guide roll 3 are not particularly limited, and may vary depending on, for example, the diameter of the crown roll 2 and the guide roll 3, the tension of the web 5, and The diameter change rate of the crown roll 2 (the difference between the diameter at the center and the diameter at the ends), web width, web material, web thickness, web running speed, etc. can be appropriately set.

In this way, the crown roll 2 and the gator 3
Through this exquisite combination, it is possible to fully draw out the potential of the web itself, which is responsible for web running stability, and to maintain good balance in the width direction of the web 5 without applying high tension. It can create a lot of tension.

Therefore, the risk of warping under high tension as in the past can be avoided to a large extent, without using complicated equipment, and even under low tension. It can effectively prevent the appearance of wrinkles.

Although FIG. 1 describes the case where the S-type traveling unit is installed in the winding section, the installation position of the S-type traveling unit according to the present invention is not particularly limited, and it can be installed anywhere on the web conveyance path. It may be the position, for example, the third position.
A device as shown in the figure may be used.

The apparatus shown in FIG. 3 has a structure in which a dancer roll 7 is disposed downstream of the S-type traveling unit 1 when the web travels.

In this case, the action of the S-type traveling unit 1 is the action of the dancer roll 7 for tension adjustment.When controlling the tension of the nib 5, the movement of the web 5 is caused by the swinging of the dancer roll 7. The same effect as described above can effectively prevent the occurrence of fraying and wrinkles in a situation where fraying and wrinkles are likely to occur due to changes in the material.

In each of the embodiments described above, only one S-type traveling unit is shown in the drawings, but of course, the present invention does not apply even if a plurality of S-type traveling units are provided in one web conveyance path.
Further, a plurality of them may be installed in succession. Furthermore, if the surface of the crown roll 2 is configured to have an appropriately curved surface, or if the surface of the crown roll 2 is configured to have a largest diameter at the center and gradually become smaller toward both ends, the surface of the crown roll 2 may have an inclination angle. Various configurations are possible, such as a continuous surface of different tapered surfaces, or a combination of a curved surface and a tapered surface.

〔Effect of the invention〕

As described above, the present invention provides for holding the web so as to wrap it around a crown roll when the web is continuously running, and also winding the web around a guide roll having a constant outer diameter across the width direction of the roller. Since the web travels between the crown roll and the guide roll in a substantially S-shaped running path, the web that is in contact with the outer peripheral surface of the crown roll is located at the outer peripheral surface of the guide roll. A state in which the web is returned to a flat state occurs, and this can be caused by a change during web running from a curved state to a flat state in the web width direction, or a subtle change in web internal stress.

Therefore, even if the tension is very small, changes in the internal stress generated in the web will cause harmonious tension in the web in the width direction, which will cause an alignment effect in the running of the web and the occurrence of wrinkling and twisting of the web. can be effectively prevented.

Therefore, according to the present invention, not only can the risk of warping due to high tension as in the past be largely avoided, but also the magnetic flux caused by wrinkles during web running can be avoided without using a complicated device. It is possible to provide a high quality thin film magnetic recording medium in which layer defects are prevented.

Hereinafter, the effects of the present invention can be further clarified with reference to Examples.

[Example 1] In the modification treatment of the magnetic layer, the manufacturing process was carried out when an S-type traveling unit was installed at the position shown in FIG.

The web was vacuum-deposited with Co-Ni and had a width of 300 mm, a thickness of 10 μm, and a length of 3000 m, and a rolled web was set on the feed side. In the vapor deposition surface modification zone 6, a step of spraying 02.03 onto the vapor deposition surface to modify the surface was performed, and as shown in FIG. 1, the film was wound into the winder via the S-shaped traveling unit.

The web processing speed (running speed) is 1 to 1 Om.
Z minute, tension is 0.5 kg ~ 2.0 kg/3
The treatment was carried out within a range of 0.00 mm.

For the S-type traveling unit (crown roll + contact roll), an oxidized bulk with a total length of 3000 m was created under the following conditions.

*The conditions for the S-type traveling unit are: - Crown roll - Material is 5US316, diameter at the center of the roll is 50 mm, diameter at both ends is 49.5 mm, total length is 400 mm.
mm a ・Contact roll: Made of fluorocarbon rubber with hardness of 80°
H1 diameter 70r++n+, total length 400mm.

- The gap between the crown roll and the contact roll at the center in the web width direction was 1 to 3+ nm.

[Example 2] Modification of the magnetic layer was carried out using an apparatus in which an S-type travel unit was installed upstream of the tension adjusting dancer shown in FIG.

The web was vacuum-deposited with C○-Ni and had a width of 300 mm, a thickness of 10 μm, and a length of 3000 m, and a rolled web was set on the feed side. In the vapor deposition surface modification zone 6, a step of spraying 0□ and 03 onto the vapor deposition surface to modify the surface was performed, and the film was wound up in a winder.

Note that the material and shape of the S-type travel unit and various other processing conditions were the same as in Example-1.

[Comparative example]

As a comparative example, a modification treatment of the magnetic layer was carried out using equipment using an expander roll. Naturally, S in Example-2
An expander roll was installed at a position corresponding to the mold traveling unit. The processing conditions were the same as in the previous example.

The material of the expander roll used is NBS rubber, the outer diameter is 70 mm, and the total length (surface length) is 500 mm.
, and there was no drive.

As a comprehensive evaluation, in each of the above examples, even when the treatment was performed at a fairly low tension of 0.5 kg to 2.0 kg/300 mm, the web did not wrinkle (as visually observed) and was extremely good. It's time to process it. On the other hand, in the comparative example, in terms of the material of the roll, the treatment with 02 did not cause any cracks on the roll surface, or the treatment with ○ caused the roll surface to crack and the processing process was delayed. It has become impossible to continue. In addition, in the case of the comparative example, the tension is 0.5 kg to 2.0 kg/30
If a drive system is not connected to the expander roll in the range of 0 mm, the roll will not rotate properly and scratches and wrinkles will occur. In other words, it can be seen that the treatment cannot be carried out with a low tension as in the embodiment of the present invention. As a result, it is clear that higher quality magnetic recording media can be provided than the magnetic recording media produced in the above embodiments which were processed under low tension.

[Brief explanation of the drawing]

FIG. 1 is a schematic view of the main parts of an apparatus implementing the web handling method for a thin film magnetic recording medium of the present invention, FIG. 2 is a perspective view of the main parts of the present invention, and FIG. 3 is a main part of another embodiment of the present invention. FIG. (Symbols in the figure) 1... S type traveling unit, 2... Crown roll, 3... Guide roll, 4... Winder, 5... Web, 6... Vapor deposition surface modification zone, 7... Dancer role. Figure 1 Figure 2 Procedural amendment dated December 19, 1990

Claims (2)

[Claims] (1) When a web of a thin film magnetic recording medium is continuously run, the web travel path is formed into a substantially S-shape by the outer peripheral surfaces of a pair of rolls constituting the web transport path, and the upstream side of the rolls is A web handling method for a thin-film magnetic recording medium, characterized in that a roll is used to pull the web to both ends in the width direction to cause the web to warp in the web width direction, and the other roll is used to guide the web so as to reverse the warp in the web width direction. . (2) In an apparatus for continuously running a web of a thin film magnetic recording medium, the web is wound around a crown roll constituting a web conveyance path, and a guide is provided near the crown roll and has a constant outer diameter across the width of the roller. A web handling device for a thin film magnetic recording medium, characterized in that the web is wound around a roll so that the running path of the web is approximately S-shaped between the crown roll and the guide roll.