JP2001084575A - Magnetic tape machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make manufacturable a magnetic tape with excellent manufacturing efficiency by providing an optical system which makes one laser beam or more, machining the back layer of a long-sized magnetic tape, incident on a specific machining position, a conveying means which conveys the magnetic tape along the longitudinal direction, and a support drum which holds the machining tape at the machining position and restricts the width-directional position. SOLUTION: The magnetic device 10 while positioning the magnetic tape T at the specific machining position W on the cylinder part 38 of the support drum 36 having a collar 40 and conveying it along the longitudinal direction (arrow X) by a tape conveying device 20 makes a laser beam incident on the machining position W by the optical system having a beam splitting optical system such as a light source 12. The magnetic tape T is conveyed with its back layer up and the back layer is machined with the laser beam to form a machining line extending along the longitudinal direction of the magnetic tape T. The magnetic tape T having the machining line is accompanied by less air even when conveyed fast, so that the magnetic tape T can stably be manufactured with high efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of magnetic tapes used for recording / reproducing information, and more specifically, does not cause slip even when a magnetic tape is conveyed at a high speed in a magnetic tape manufacturing process or the like. The present invention relates to a magnetic tape processing apparatus for producing a magnetic tape with small cupping.

[0002]

2. Description of the Related Art A magnetic tape used for recording and reproducing information basically includes a base layer which is a film such as PET (polyethylene terephthalate) and a magnetic layer formed on one surface of the base layer. For the purpose of improving transport stability and strength, the magnetic recording medium has a back layer formed on the opposite surface of the magnetic layer of the base layer.

In the process of manufacturing such a magnetic tape, the magnetic tape (hereinafter referred to as a tape) is subjected to various processes such as cutting by a slitter and cleaning of a surface by a blade while being transported in a longitudinal direction. And then rolled up in a hub or the like to make pancakes or cassettes and sent to the next process or delivery destination. In recent years, in order to improve productivity, various processes (such as manufacturing equipment such as blade machines and winder machines) ) Tends to increase the tape transport speed.

[0004] In general, the tape is conveyed by winding the tape around a capstan roller and rotating the capstan roller. However, when the transport speed of the tape is increased, in a manufacturing apparatus such as a blade machine, the tape entrains air, and the tape floats on a capstan roller or the like, thereby causing the tape to slip, thereby preventing normal transport. There are cases.

As a result, the tape becomes a capstan roller,
The tape is damaged or improperly collides with the guide roller, blade blade, etc., and the tape or tape edge is broken, or the tape is damaged such as abrasion or peeling of the magnetic material layer. Will be. Further, the tape manufacturing apparatus is provided with a roller (measurement roller) for measuring the length of the tape as necessary. However, if the tape slips, an error occurs in the measurement of the tape length, and the production control is performed. Also cannot be performed properly. for that reason,
It has been difficult to increase the tape transport speed in tape manufacturing so as to properly meet the required production efficiency.

[0006] Another problem of the tape is as follows.
Curling (curving) in the width direction of the tape, so-called cupping, is known. Cupping is mainly caused by the difference in the shrinkage of the binder used between the magnetic layer and the back layer. When cupping occurs, the appearance of the magnetic tape as a product deteriorates; And the like, which may cause a recording error or a reading error; damage to the edge of the magnetic tape is likely to occur;

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art. In a magnetic tape manufacturing apparatus such as a blade machine and a winder machine, the tape transport speed is increased. To provide a magnetic tape processing apparatus capable of producing a magnetic tape having excellent characteristics without causing slip of the tape in a capstan roller or the like, and furthermore, having a small cupping at a good production efficiency. is there.

[0008]

In order to achieve the above object, the present invention provides an optical system for projecting at least one laser beam for processing a back layer of a long magnetic tape into a predetermined processing position; Conveying means for conveying the magnetic tape in the longitudinal direction, having an axis in a direction perpendicular to the conveying direction of the magnetic tape, and supporting the magnetic tape on the side surface, with the back layer facing the laser beam incident side A cylindrical portion that holds the magnetic tape at the processing position, and a supporting drum that is provided on the cylindrical portion and has a flange that regulates a position in the width direction of the magnetic tape by contacting an end of the magnetic tape. Provided is a magnetic tape processing device characterized by having:

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic tape processing apparatus according to the present invention will be described below in detail with reference to the preferred embodiments shown in the accompanying drawings.

The magnetic tape processed by the magnetic tape processing device of the present invention (hereinafter referred to as a processing device) is made of PET.
Layer (base film) made of amide or aramid resin
Layer structure having a magnetic layer on one side and a back layer (back coat layer) on the other side of the base layer, or further having an overcoat layer (protective layer) and an undercoat layer And processed by the processing apparatus of the present invention to form a recess (preferably a groove) in the back layer.

FIG. 1 shows a magnetic tape processed by the processing apparatus of the present invention and having a concave portion formed in a back layer (hereinafter referred to as a magnetic tape).
An example of the back layer is conceptually shown. FIG.
The example shown in (A) is an example in which a plurality of grooves (processing lines a) extending in the longitudinal direction of the tape are formed in the back layer of the tape. Further, the example shown in FIG.
In the example shown in (A), the processing of the back layer is intermittent (or patterned), and the processing line is divided into lines (processing line segment b).

Incidentally, the shape (cross-sectional shape) of such a concave portion
Is not particularly limited, and examples thereof include a rectangle, a triangle, and a semicircle (bow). Such a shape may be adjusted by the beam spot intensity distribution of the laser beam for processing the back layer. The depth of the recess is not particularly limited, and may be appropriately determined according to the strength of the tape or the like. However, in order to obtain a good effect, the depth of the recess is preferably 0.1 μm or more. In particular, the thickness is preferably 0.2 μm or more. Further, the size (line width) and the formation density of the concave portion are not particularly limited, and may be appropriately determined according to the strength and width (size) of the tape. For example, when a processing line or the like extending in the longitudinal direction as shown in FIG. 1 is formed on a tape having a width of 0.5 inch, the width is about 3 μm to 10 μm, and several to 100 in the width direction. It is preferable to form a degree of processing line or the like.

The tape having such a concave portion in the back layer has a small amount of air entrainment by the tape even when the tape is conveyed (running) at a high speed, and even when air is entrained, the tape can be suitably removed from the concave portion. Therefore, even when the tape is conveyed at high speed by a tape manufacturing apparatus such as a blade machine, the tape does not rise and slip due to the capstan roller or the like, and there is no damage or error in the conveyance length caused by the tape. Therefore, by using this tape, it is possible to carry out high-speed and accurate tape conveyance, and to produce a magnetic tape of proper quality stably and efficiently under proper production management. In addition, the tape T according to the present invention also preferably passes through the air between the tapes at the time of winding, so that the wound form when wound on a cartridge or pancake is beautiful.

Further, this tape having a concave portion in the back layer has less cupping than the conventional tape, and has a lower appearance, worsening per head, and damage to the tape edge due to the cupping than the conventional tape. And greatly reduced. The reason why cupping can be reduced by forming a concave portion in the back layer is not clear,
It is considered that since the stress generated in the width direction of the tape due to the difference in the shrinkage ratio of the binder is cut at the concave portion, the force generated in the width direction of the tape is reduced as a whole, and as a result, cupping can be prevented.

FIG. 2A is a conceptual diagram of a processing apparatus of the present invention for producing a (magnetic) tape having such a concave portion. The illustrated processing apparatus 10 includes an optical system having a light source 12, a pulse modulator 14, a mirror 16, and a beam splitting optical system 18, and a tape transport device 20.

In such a processing apparatus 10, the tape T is moved to a predetermined processing position W by the tape transport device 20.
And transported (running) in the longitudinal direction (direction of arrow x in the figure)
While the laser beam is incident on the processing position W by the optical system. Here, since the back layer of the tape T is transported upward (toward the laser beam incident side), the back layer of the tape T is processed by the laser beam, and extends in the longitudinal direction of the tape T as described above. An existing processing line or the like is formed.

The light source 12 emits a laser beam for processing the back layer of the tape T. The light source 12 is not particularly limited, and various laser beam light sources (laser oscillators) can be used as long as a laser beam having an output capable of processing the back layer can be emitted. One that can emit at least one of a laser beam and a laser beam in the visible region is used. In terms of workability, a laser beam with a short wavelength is more preferable,
A laser beam in the ultraviolet region is the best, but a laser beam in the visible region is preferable in terms of cost, safety, workability, and the like. Specifically, an argon (ion) laser of 488 nm or 515 nm or a YAG laser is applied to SHG (Second Harm
An example is a light source that emits a 532 nm laser beam whose wavelength is converted by an onic generation (second harmonic generation) element.

The pulse modulator 14 pulse-modulates a laser beam emitted from the light source 12 to form a processing line segment b or the like as shown in FIG.
Therefore, in the case where the light source 12 can be directly modulated,
In the case where only the processing line a as shown in (A) is formed, the pulse modulator 14 is unnecessary. As the pulse modulator 14, known modulation means such as an AOM (acoustic optical modulator) can be used. The processing line segment may be patterned by modulation.

The laser beam is reflected by a mirror 16 in a predetermined direction, and then enters a beam splitting optical system 18.
In addition, between the mirror 16 and the beam splitting optical system 18, if necessary, a beam expander for expanding the beam diameter of the laser beam, or making the intensity of the laser beam substantially uniform over the entire beam spot, that is, Various optical members such as a beam profile shaper for making the beam intensity distribution substantially uniform may be arranged.

The beam splitting optical system 18 splits one laser beam into a plurality of laser beams arranged in the width direction of the tape T (the direction orthogonal to the transport direction), and separates each split laser beam into a processing position. It is incident on W. As such a beam splitting optical system 18, various optical systems can be used as long as they have the above-mentioned functions. As a preferable example, the one shown in FIG. 3 is exemplified.

The beam splitting optical system 18 includes a beam waist position adjusting means 22, a beam splitter 24, and a converging lens 26. In addition,
FIG. 3 shows this optical system viewed from the longitudinal direction of the tape T. Therefore, the tape T is conveyed at a processing position W in a direction perpendicular to the plane of the paper.

In the beam splitting optical system 18 shown in FIG. 3, after the beam waist position is adjusted by the beam waist position adjusting means 22, the beam splitter 24 adjusts the laser beam according to the number of processing lines to be formed. The laser beam is divided into a plurality of laser beams arranged in the width direction of the tape T (beam No. 1 to beam No. N). The split laser beam is converged and imaged by the converging lens 26, and is incident on the back layer of the tape T conveyed in the longitudinal direction while being held at the processing position W by the tape conveying device 20. Thereby, each laser beam processes the back layer, and a plurality of processing lines (recesses) extending in the longitudinal direction of the tape T are formed on the back layer according to the number of laser beams incident on the back layer of the tape T. It is formed.

Here, in this optical system, the laser beam does not form an image at the processing position W (ie,
The processing position W is not a convergence position of the laser beam by the converging lens 26) but is adjusted by the beam waist position adjusting means 22 so that the beam waist position comes to the processing position W. As shown in FIG. 3, since the optical path lengths of the laser beams split by the beam splitter 24 are substantially equal, the beam waist position W of each laser beam
Are substantially coplanar.

The beam waist position adjusting means 22 is a known laser beam waist position adjusting means. For example, using a group lens or the like whose position on the optical axis and the distance between each other can be adjusted, ABC derived by Kogelnik
Means for adjusting the position of the beam waist based on the calculation using the D matrix is exemplified. Beam splitter 24
There is no particular limitation, and various known devices can be used as long as one laser beam can be divided into a plurality of beams arranged in one direction, such as a beam splitter using a dielectric multilayer film.

FIG. 4 shows another example of the beam splitting optical system. The beam splitting optical system 28 shown in FIG. 4 uses a rod lens 30, a cylindrical lens 32, and an aperture plate 34 having a large number of apertures in place of the beam splitter 24. Similarly, the laser beam that has been divided and dim so that the processing position W becomes the beam waist is transmitted to the processing position W
Then, the light enters the back layer of the tape T held on the tape to form a processing line.

That is, beam waist position adjusting means 2
The laser beam whose beam waist position has been adjusted by 2 is expanded in the width direction of the tape T by the rod lens 30 and then converted into parallel light (made into a sheet-like laser light) by the cylindrical lens 32. The sheet-shaped laser light is then incident on an aperture plate 34 having a large number (N) of apertures (holes) arranged in the width direction of the tape T, and the laser light passing through the holes is
The laser beam divided into N laser beams arranged in the width direction is incident on the converging lens 26, is converged and is incident on the processing position W, and forms a processing line on the back layer of the tape T. In this beam splitting optical system, the method of converting the laser beam into a sheet-like laser beam is not limited to the method using the rod lens 30 and the cylindrical lens 32, and various known methods can be used.

In the processing apparatus of the present invention, the optical system for processing the back layer by irradiating the laser beam to the processing position W (the back layer of the tape T) is not limited to the above-described example. One or more laser beams, preferably a plurality of laser beams, more preferably a plurality of laser beams obtained by dividing one laser beam are incident on the laser beam, and an image is formed (or the beam waist position coincides with the processing position). Various types of optical systems can be used as long as they can process the back layer.

For example, in the example shown in FIG. 4, a multi-lens in which a number of lenses are arranged in the width direction without using the beam waist position adjusting means 22 and instead of the aperture plate 34 and the converging lens 26. Is exemplified. In this optical system, the laser light formed into a sheet by the cylindrical lens 32 is incident on the multi-lens. By forming the laser light incident on each lens of the multi-lens on the back layer of the tape T located at the processing position W by each lens, a plurality of laser beams arranged in the width direction are formed. And the back layer is processed by this.

As described above, the tape T is positioned in the processing position W in the longitudinal direction (the direction of the arrow x) while the back layer thereof is directed upward (the laser beam incident side) by the tape transport device 20. Conveyed (conveyed with the longitudinal direction coincident with the conveying direction). Therefore, the processing position W
A plurality of processing lines extending in the longitudinal direction are formed in the back layer of the tape T by a plurality of processing lines extending in the longitudinal direction (N in the above-described example) by a plurality of laser beams arranged in the width direction. Is done. The tape transport device 20 is configured by appropriately combining a capstan roller, a pinch roller, a winder, a rewinder, a guide roller (42, 44), and the like.
It comprises a known tape transporting means (detailed omitted) for transporting the tape T in the longitudinal direction, and a support drum 36.

As shown in FIGS. 2A and 2B, the supporting drum 36 includes a cylindrical portion 38 having an axis in the width direction of the tape T, and cylindrical portions disposed on both end surfaces of the cylindrical portion 38. 38, and is composed of disk-shaped flanges 40 and 40 having a large center and a center.

In the illustrated example, the holding drum 36 is arranged such that the uppermost portion of the side surface of the cylindrical portion 38 is the processing position W. The tape T is guided upward by the guide roller 42, is supported from below by the side surface of the cylindrical portion 38 of the holding drum 36, passes through the processing position W, is guided downward by the guide roller 44, and is conveyed to the next step. Is done. In addition, the tape T has a flange 4
By abutting on 0, it does not move more than a predetermined amount in the width direction at the processing position W. In other words, in the processing apparatus of the present invention, the tape T is positioned by the side surface of the cylindrical portion 38 having the axis in the width direction in the depth of focus direction (the laser beam advancing direction).
Thus, the position in the width direction is regulated, and a part is conveyed in the longitudinal direction while being positioned at the processing position W with high precision to process the back layer.

In the present invention, if the tape T is in contact with and supported by the cylindrical portion 38 in accordance with the state of winding of the tape T around the cylindrical portion 38, the tape T is not necessarily required. The uppermost part does not need to be the processing position W of the tape T. Further, in terms of processing accuracy, processing density, and the like, the position of the cylindrical portion 38 and the optical system is set such that the laser beam is perpendicularly incident on the tape T (so that the laser beam is directed to the axis of the cylindrical portion). Is preferred.

The support drum 36 may be engaged with a drive source and rotate by itself according to the transport speed of the tape T, or may be rotatably supported by bearings or the like.
The rotation may be performed by using the transport of the tape T as a driving source. The diameter of the cylindrical portion 38 is also not particularly limited, and the transport path, the size (width) of the tape T to be processed, and the processing position W
May be determined as appropriate according to the device configuration (members and the like arranged in the vicinity).

The interval w between the flanges 40 is based on the width of the tape T to be processed as a basis, the width accuracy (variation in the width) of the tape T to be processed, and the processing accuracy (processing line width) required for the processing apparatus of the present invention. The width T may be determined as appropriate in accordance with the position accuracy in the width direction), and therefore may be larger or smaller than the width of the tape T. There are various types of tapes T, and there is no particular limitation. Usually, this interval w is the width of the tape T ± 0.005 m.
m to about ± 0.1 mm. Also, the height h of the flange 40
There is no particular limitation on the (step difference from the cylindrical portion 38). The height may be set so that the position in the width direction of the tape T can be appropriately regulated by contacting the tape edge.
It is about 5 mm. Further, the flange portion 40 includes a circumferential portion 38.
It may be a plane (linear) orthogonal to (the side surface) or a plane having a curvature (rounding). The plane initially has a curvature and is ground by use to become a plane orthogonal to the plane. May be. The orthogonal plane is
Although the positional accuracy of the tape T in the width direction can be increased, the possibility of causing damage to the tape edge is increased. Therefore, it may be determined appropriately according to the required accuracy and the like.

In the illustrated example, the flange portions 40 are located at both ends of the cylindrical portion 38, but the present invention is not limited to this, and is formed so as to project from the side surface of the cylindrical portion 38. You may. Further, even if the cylindrical portion 40 and the flange portion 40 are integrally formed, the support drum 36
May be configured. Further, if the target position accuracy in the width direction of the tape T can be achieved, the flange portion 40 is
It may not be formed over the entire circumference of the cylindrical portion 38, but may be formed intermittently in the circumferential direction.

In the processing apparatus of the present invention using a laser beam, both the thermal processing of the laser beam and the processing by ablation (dissociation and separation) with the laser beam occur in combination, and the back layer is processed. It is thought that. For this reason, processing scum (dust and the like) and harmful gas may be generated by processing the back layer. In the processing apparatus of the present invention, in order to prevent contamination of the working environment and damage and dirt on the front and back surfaces of the tape, the processing position W
Downstream (in the transport direction of the tape T), cleaning means (such as an adhesive tape) for cleaning the surface of the tape T,
A duct or the like for sucking gas may be provided.

FIG. 5 schematically shows another example of the (magnetic tape) processing apparatus of the present invention. The example shown in FIG.
A plurality of the processing apparatuses 10 shown in FIG. 2 are arranged in the transport direction of the tape T, and processing lines (recesses) formed by the processing apparatuses 10 are moved in the width direction by, for example, a method of adjusting the position of an optical system. It has a configuration shifted to. With such a configuration, the processing density of the processing lines formed on the back layer of the tape T can be improved.

In the example shown in FIG. 5B, a plurality of optical systems including the light source 12 and the beam splitting optical system 18 are arranged for one holding drum 36, and the same as in the previous example. It has a configuration in which processing lines formed by the respective optical systems are shifted from each other in the width direction. Also in this configuration, similarly, the processing density of the processing line formed on the back layer can be improved. Alternatively, the laser beam emitted from one optical system may be divided in the transport direction of the tape T and made incident on different positions in the width direction to improve the processing density of the processing line.

The above-described processing of the tape T according to the present invention may be performed at any time during the magnetic tape manufacturing process as long as the back layer is formed. For example, before the tape is cut into a product width by a slitter. Or after cutting.

Although the magnetic tape processing apparatus of the present invention has been described in detail above, the present invention is not limited to the above-described example, and various modifications and changes can be made without departing from the gist of the present invention. Good.

[0041]

As described above in detail, according to the magnetic tape processing apparatus of the present invention, even when the transport speed is increased, the magnetic tape processing apparatus does not slip by the capstan roller or the like, and therefore, can transport at high speed and accurately. , And a magnetic tape having excellent characteristics with little cupping can be efficiently obtained. By using the magnetic tape manufactured by such a processing apparatus of the present invention, high-speed and accurate tape conveyance can be performed in a magnetic tape manufacturing apparatus such as a blade machine, and as a result, under appropriate production management. , Stable production of magnetic tape with no damage, high quality of appearance when wound on cartridges and pancakes, and reduced tape appearance due to cupping, deterioration of head contact, Damage to the tape edge can also be prevented.

[Brief description of the drawings]

FIGS. 1A and 1B are conceptual diagrams each showing an example of a back layer of a magnetic tape processed by a magnetic tape processing apparatus of the present invention.

FIG. 2A is a conceptual diagram of an example of a magnetic tape processing apparatus of the present invention, and FIG. 2B is a schematic view of a holding drum of the magnetic tape processing apparatus shown in FIG. FIG.

3 is a conceptual diagram of an example of a beam splitting optical system used in the magnetic tape processing device shown in FIG.

4 is a conceptual diagram of another example of the beam splitting optical system used in the magnetic tape processing device shown in FIG.

FIGS. 5A and 5B are conceptual diagrams for explaining another example of the magnetic tape processing device of the present invention.

[Explanation of symbols]

 Reference Signs List 10 (magnetic tape) processing device 12 light source 14 pulse modulator 16 mirror 18, 28 beam splitting optical system 20 tape transport device 22 beam waist position adjusting means 24 beam splitter 26 converging lens 30 rod lens 32 cylindrical lens 34 aperture plate 36 holding drum 38 cylindrical part 40 flange part 42,44 guide roller

Claims (1)

[Claims] 1. A method for processing a back layer of a long magnetic tape.
An optical system that causes the above laser beam to enter a predetermined processing position, and a transport unit that transports the magnetic tape in a longitudinal direction,
A cylindrical portion that has an axis in a direction perpendicular to the direction of transport of the magnetic tape and holds the magnetic tape at the processing position with the back layer facing the laser beam incident side by supporting the magnetic tape on the side surface, And a support drum provided on the cylindrical portion and having a flange portion that abuts on an end portion of the magnetic tape to regulate a position in a width direction of the magnetic tape.