JP2001091155A - Drying equipment and magnetic tape manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide drying equipment to prevent the occurrence of a shift of a wide sheet and nozzle contact. SOLUTION: A magnetic tape is a wide sheet 3. An upper nozzle 6 blows hot air against an upper surface 3a of the wide sheet 3. A lower nozzle 7 blows hot air against an under surface 3b of the wide sheet 3. A lower nozzle 7 blows hot air against an under surface 3b of the side sheet 3. A guide roll 8 is situated below the upper nozzle 6. The guide roll 8 makes contact with the under surface 3b of the wide sheet 3. Further, impellers are situated at the two ends of the guide roll 8. By blowing hot air supplied through the nozzle 6 against the impeller, the guide roll 8 is rotationally driven. Further, the guide roll 8 has conductivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying facility and a magnetic tape manufacturing apparatus using the same.

[0002]

2. Description of the Related Art Conventionally, a guide roll drier and a floating drier are provided as drying equipment of a coating machine in a magnetic tape manufacturing process, and each has the following features.

The characteristics of the guide roll dryer are as follows:
Since hot air required for drying the magnetic tape is blown from the upper surface of the magnetic tape, the adhesion between the guide roll and the magnetic tape is good, and the running is stabilized. However, due to the good adhesion between the guide roll and the magnetic tape, unless the guide roll is rotated by a motor, the tape is scratched, so the guide roll has to be rotated.

On the other hand, the guide roll dryer has a low drying capacity because hot air is blown only from the upper surface of the magnetic tape. Therefore, due to the problem of residual solvent, the total length is 40 m.
It was not possible to produce at a speed of about 200 m / min or more with the guide roll dryer. That is, the drying time could not be reduced to about 12 seconds or less.

For this reason, while high-speed production has recently progressed, floating dryers have become the mainstream due to the problem of residual solvents. The floating dryer is a drying equipment suitable for high-speed production because it has a high drying capacity because hot air required for drying the magnetic tape is blown from the upper and lower surfaces of the magnetic tape.

However, since the hot air is blown from above and below the magnetic tape, the balance between the hot air in the upper and lower directions greatly affects the running of the magnetic tape. Further, since the film thickness and the coating thickness of the magnetic tape differ depending on the type, it is necessary to change the setting of the amount of hot air and the vertical balance for each type. That is, if the film thickness and the coating thickness of the magnetic tape are different, the weight per unit of the magnetic tape changes. Therefore, it is necessary to change the setting of the amount of hot air and the vertical balance for each product in order to sufficiently float the magnetic tape and smoothly run between the upper nozzle and the lower nozzle.

[0007]

In running a magnetic tape in a floating dryer, the balance between the amount of hot air blown from the upper and lower surfaces of the magnetic tape and the upper and lower sides is not stable. The dry magnetic tape contacts the nozzle that blows hot air,
The occupancy rate and yield were reduced.

[0008] When a thin film having a large curvature is run, the film runs while bending without running at the center in the floating dryer. At that time, tension is applied in the longitudinal direction of the film, and the film travels while folding and overlapping in the width direction, so that a tape shift is likely to occur. Further, if the opposite directions of the curved films are continued at the production speed, the tape shift is likely to occur at this time, so that the continuous operation is performed at a reduced speed. In other words, when the film curved to one side in the width direction is run and then the film curved to the other side in the width direction is continuously spliced, the running position changes suddenly, so that if the speed is high, the magnetic tape may be cut. Become. Therefore, it is continuous at a reduced speed. As a result, the length yield decreases.

In addition, since the balance of the hot air volume between the upper and lower nozzles is poor in the undried magnetic tape, the magnetic tape runs closer to the nozzles without running at the center of the upper and lower nozzles. Since the balance of the hot air blown from the nozzle in the width direction is poor, undulation may occur in the width direction of the tape, and the peak of the undulation may come into contact with the nozzle.

The present invention has been made in view of the above problems, and has as its object to provide a drying apparatus capable of preventing a wide sheet such as a magnetic tape from shifting or contacting a nozzle, and a magnetic tape manufacturing apparatus using the same. And

[0011]

The drying equipment of the present invention comprises:
(A) It has the following upper nozzle and lower nozzle. (A-1)
The upper nozzle blows hot air onto the running wide sheet from the upper surface of the wide sheet. (A-2) The lower nozzle blows hot air onto the wide sheet from the lower surface of the wide sheet. Also, the following drying equipment (B). (B-
1) A guide roll is provided below at least one of the upper nozzles. (B-2) The guide roll contacts the lower surface of the wide sheet.

Further, the drying equipment of the present invention is a drying equipment having the above-mentioned configuration, characterized in that: (A) Impellers are provided at both ends of the guide roll. (B) The guide roll is driven to rotate by applying hot air blown from the upper nozzle to the impeller.

Further, the drying equipment of the present invention is a drying equipment having the above-mentioned configuration, characterized in that: (A) The following current plate is provided. (A-1) The current plate is located below the upper nozzle. (A-2) The rectifying plate causes the hot air blown from the upper nozzle to impinge on the impeller of the guide roll.

Further, the drying equipment of the present invention is a drying equipment having the above-mentioned configuration, characterized in that: (A) The guide roll has the following first and second impellers at both ends. (A-1) The first impeller and the second impeller have wings attached at the same pitch. (A-2) The wings of the first impeller and the wings of the second impeller are mounted so as to be shifted from each other by a half pitch.

Further, the drying equipment of the present invention is the drying equipment having the above-mentioned configuration, characterized in that: (A) The guide roll has conductivity.

The magnetic tape manufacturing apparatus of the present invention is the following magnetic tape manufacturing apparatus. (A) Includes the drying equipment of the above configuration. (B) The wide sheet is a magnetic tape.

According to the drying equipment and the magnetic tape manufacturing apparatus of the present invention, a guide roll is provided below the upper nozzle, and the guide roll is brought into contact with the lower surface of the wide sheet, whereby the wide sheet is supported by the guide roll. To run.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention relating to a drying facility and a magnetic tape manufacturing apparatus using the same will be described below with reference to FIGS.

FIG. 5 is a diagram schematically showing a conventional magnetic tape coating machine. In the magnetic tape applicator shown in FIG. 5, the magnetic paint is applied to the base material 2 unwound from the unwinding section 1, the applied wide sheet 3 is dried by the drying equipment 4, and the dried wide sheet 3 is wound up. This is a device for winding in the section 5.

FIG. 6 is a diagram schematically showing the inside of a drying facility of a conventional magnetic tape coating machine. The drying equipment here is a so-called floating drier having a total length of about 40 m, and is a device that floats the wide sheet 3 in a beautiful sine curve shape with hot air blown from the upper and lower surfaces of the wide sheet 3 to dry and run. . Conditions that affect the running of the floating dryer include the gap between the upper nozzle 6 and the lower nozzle 7 from which hot air is blown, the amount of hot air from the upper nozzle 6 and the lower nozzle 7, balance, and the shape of the wide sheet 3 (thickness of the wide sheet 3). Unevenness, wrinkles, curvature, etc.), cutting position,
There is a tension of the wide sheet 3 in the dryer and the like.

The above conditions have been changed according to the type of product to be produced, but the tape shift sometimes occurs when the reproduction cannot be performed accurately and when the film shape is bad. The wide sheet 3 contacts the upper nozzle 6, thereby lowering the operation rate and the quality yield. Here, the quality yield means that the semi-dry semi-dry wide sheet 3 is scratched or marked due to contact with the upper nozzle, resulting in poor quality.

Therefore, the running stability of the wide sheet 3 was improved by inserting a guide roll just below the upper nozzle 6 of the floating dryer so as to accurately reproduce the conditions and not to be influenced by the film shape.

First, the drying equipment according to the present invention will be described. FIG. 1 is a diagram showing an embodiment of the invention relating to a drying facility. The wide sheet 3 is a sheet having flexibility, such as a magnetic tape. On the drawing,
The wide seat 3 runs from the left side to the right side.

The upper nozzle 6 is attached to the running wide sheet 3.
The hot air is blown from the upper surface 3 a of the wide sheet 3. The lower nozzle 7 blows hot air onto the wide sheet 3 from the lower surface 3b of the wide sheet 3.

Next, the guide roll 8 will be described in detail with reference to FIG. FIG. 2 is a view showing a guide roll used in the drying equipment of the present invention. The outer shape of the guide roll 8 was 80 mm. Note that the outer shape of the guide roll 8 is desirably in the range of 60 to 100 mm. If the outer shape is smaller than 60 mm, the rolls will bend due to the weight of the guide rolls, resulting in a disadvantage that the entire wide sheet cannot be supported by the guide rolls. The outer shape is 1
If it is larger than 00 mm, it will not fit in the nozzle span, and the length of the dryer will be long.

Considering a reduction in the weight of the guide roll 8, an aluminum material is desirable, and the surface treatment is performed by using ultra-hard alumite or hard chrome plating. Further, the guide roll 8 has conductivity. In order to retain conductivity, the surface of the guide roll 8 is subjected to a wear-resistant surface treatment, and the material of aluminum is treated with conductive (carbon) ultra-hard alumite and hard chrome plating. I have. Here, the reason for imparting conductivity to the guide rolls 8 is that the inside of the dryer is used in an atmosphere of an organic solvent to prevent generation of static electricity on the wide sheet.

As shown in FIG. 1, a guide roll 8 is provided below at least one of the upper nozzles 6. The guide roll 8 is provided on the lower surface 3 b of the wide sheet 3.
Contact with The number of the guide rolls 8 to be installed is such that, for example, a thick base having a thickness of 14 to 20 μm can run even every other one, but a thin base having a thickness of 7.2 to 9 μm cannot run. You need to put a roll.

As shown in FIG. 1, the mounting position of the guide roll 8 is determined with reference to the upper surface of the lower nozzle 7.
Is made 2 mm higher than the upper surface of the lower nozzle 7. Also,
The gap between the upper surface of the guide roll and the lower surface of the upper nozzle is 6
mm. This 6 mm gap is the same as the conventional gap of 6 mm between the lower surface of the upper nozzle and the upper surface of the lower nozzle. As described above, the gap is the same as that of the related art, but the ridge of the sine curve of the magnetic tape is reduced by the contact of the guide tape and the magnetic tape, so that the magnetic tape is less likely to contact the upper nozzle 6.

The distance between the upper surface of the lower nozzle and the upper surface of the guide roll is not limited to 2 mm, but is 1 to 4 mm.
Is desirably within the range. It is desirable that the distance between the lower surface of the upper nozzle and the upper surface of the guide roll is 6 to 10 mm. If this interval is smaller than 6 mm, there is a disadvantage that the wide sheet is close to the upper nozzle and comes into contact with the upper nozzle when the wide sheet travels. Also, this interval is 10m
If it is larger than m, the force for pressing the wide sheet against the guide rolls is weakened, and there is a disadvantage that wrinkles are easily generated.

Since there is a fear that the wide sheet 3 may be scratched when the guide roll 8 is put in the drying equipment, the guide roll 8 is driven. As a driving method, a method using a motor and a method using air are conceivable. Here, hot air blown from a nozzle is used as a driving source.

Therefore, as shown in FIG. 2, impellers 12 are provided at both ends of the guide roll 8. That is, the guide roll 8 has a first impeller and a second impeller at both ends.
If the number of blades of the impeller is too small, the number of hot air hits is small, and if it is too large, the amount of hot air taken in is small. As a result of the test, an appropriate number of blades was set to eight. Note that the number of wings is not limited to eight. The number of feathers is 6-1
It is desirable to be within the range of 0 sheets. If the number of wings is less than 6, there is a disadvantage that the interval of receiving the hot air is too large and it is difficult to rotate at the time of starting. On the other hand, if the number is more than 10, there is a drawback that the wings cannot sufficiently receive hot air and the efficiency becomes poor.

The first impeller and the second impeller have wings attached at the same pitch. Further, the wings of the first and second impellers are mounted so as to be shifted from each other by a half pitch. That is, the mounting pitch of the impellers mounted on both ends is shifted by a half pitch so that hot air easily hits the impellers of the guide rolls. As shown in FIG. 3, the blades of the right and left guide rolls 8 were mounted so as to be shifted by a half pitch (22.5 °) so that hot air would always hit the blades of the wheel. As can be seen from FIG. 3, the impeller 12 on the back side and the impeller 12 on the front side are the upper nozzle 6.
It is designed to alternately receive wind from the air, so that hot air always hits the impeller wings.

In order to make the guide roll rotate as easily as possible, the static balance of the guide roll was set to 5 g or less. Here, the static balance of 5 g means that the guide roll rotates at any position when a weight of 5 g is lowered on the outer periphery. The reason for setting the static balance to 5 g or less is
In order to rotate lightly, if it is 3 g or less, the production cost becomes expensive, so that the torque is set to 20 gcm.

In order to reduce bearing mechanical loss, a guide roller and a shaft were integrated and a small-diameter bearing having a large gap was used. When the guide roll and the shaft are integrated, a small bearing is used structurally, so that the bearing mechanical loss can be reduced. In addition, when a bearing having a large gap is used, the mechanical loss of the bearing can be reduced even if it is thermally expanded by a dryer used at a high temperature.

It is also important to select grease for the bearing used at a dryer temperature of about 100 ° C.
When a polyalphaolefin-based heat-resistant grease (trade name: U-4, manufactured by Nippon Oil Co., Ltd.), which is excellent in high speed and rust resistance, can be used for at least 1000 hours.

FIG. 3 is a diagram showing a state where the impeller of the guide roll is driven to rotate by hot air from the upper nozzle. As shown in FIG. 3, the current plate 9 is provided at a position below the upper nozzle 6. The material of the current plate 9 is made of stainless steel. The material of the current plate 9 is not limited to stainless steel, but may be iron, aluminum, plastic, or the like.

When the guide roll is driven by using the hot air of the drying device, a rectifying plate 9 is attached so that the hot air blown from the upper nozzle 6 hits the impeller 12 of the guide roll. As shown in FIG. 3, the hot wind blown out from the upper nozzle 6 directly above the guide roll is applied to the flow straightening plate 9, and the hot wind is collected by impellers 12 provided on both sides of the guide roll, so that the rotation drive can be given. Thus, the guide roll can be rotationally driven by applying the hot air blown from the upper nozzle to the impeller.

Further, since the production speed and the peripheral speed of the guide roll did not match, there was a concern that the wide sheet would be scratched. However, it was confirmed that there was no problem in quality, and it was found that the above problem was solved. .

As a result of actual measurement, the production speed is 350 to 600 m
/ Min, and the guide roll peripheral speed is 100 to 3
It was in the range of 0 m / min. As a result, it can be seen that the value of guide roll peripheral speed / production speed is in the range of 1 / 3.5 to 1/20. Even if there is a difference between the production speed and the guide roll peripheral speed, the reason why scratches do not occur on the wide sheet is that when the wide sheet is run at high speed, air is carried along with the tape and the guide roll and the wide It is considered that an air layer is formed between the sheets.

The range of the guide roll peripheral speed / production speed is preferably in the range of 1/5 to 1/30. However, in this case, the production speed is desirably 300 m / min or more. At a production speed of 300 m / min or more, since an air film is generated, the wide sheet is hardly scratched.

Next, a magnetic tape manufacturing apparatus to which the above-described drying equipment is applied will be described with a specific example. Here, running was confirmed under the following conditions in a coating machine having a drying facility having a total length of about 40 m. The running position and state of the magnetic tape at that time were measured.

The operating conditions in the drying equipment according to the present invention were as shown below. A magnetic tape is used as the wide sheet. The width of the magnetic tape is 1240 mm, and the length of the magnetic tape is 16000 m. The production speed was 350 m / min. The magnetic tape tension in the drying equipment was 15 kg, 12 kg, or 10 kg. The thickness of the magnetic tape is 20 μm, 14 μm, 12 μm
m, 11 μm, 9 μm, 7.5 μm, 7.2 μm. The temperature in the drying equipment was 100 ° C. The nozzle pressure is 36 mmAq for the upper nozzle and 26 mmAq for the lower nozzle.

For comparison, the running of the magnetic tape was confirmed for a conventional floating dryer. Here, the nozzle pressure is 36 mmAq for the upper nozzle and 33 mmAq for the lower nozzle. Other implementation conditions were the same as the implementation conditions described above.

The contents of the measurement include the operating rate, the length yield, the average speed, the running position, the thread, the scratch, the tape shift, and the amount of bending. The operation rate is the actual operation time / possible operation time. The length yield is the product length / input length. The average speed is the average of the production speed and the continuous roll speed. The running position is where the magnetic tape runs between the upper nozzle and the lower nozzle. The scratches and scratches mean whether or not the magnetic tape is not scratched or scratched due to poor rotation of the guide roll. The tape shift refers to whether the tape has shifted in the tape width direction while the magnetic tape is running, and a tape break has occurred.
When the curved film is run, the film travels while moving in the direction in which the film itself is desired to bend. In this case, the amount of bending is the moving distance. FIG. 4 is a diagram illustrating the concept of the amount of bending of a curved wide sheet.

Table 1 shows the test results of the above measurement contents.

[0046]

[Table 1]

Here, the examples are the results of a test using a drying facility according to the present invention for a magnetic tape having a thickness of 11 μm. The comparative example is a test result using a conventional floating dryer for a magnetic tape having a thickness of 11 μm.

Looking at the operating rate of Table 1, the comparative example is 81.7%, while the working example is 89.4%. Here, it is desirable that the operation rate is 90% or more. Therefore, the comparative example does not satisfy this condition, but the example almost satisfies this condition.

Looking at the length yield, the comparative example shows 91.
The example is 97.95% compared to 57%. The length yield is desirably 95% or more.
Therefore, the comparative example does not satisfy this condition, but the example satisfies this condition.

The average speed is 335.
In contrast to 1 m / min, the example is 347.4 m
/ Min. The average speed is desirably 350 m / min or more. Therefore, the comparative example does not satisfy this condition, but the example almost satisfies this condition.

Looking at the traveling position, both the comparative example and the example are "OK". “OK” at the traveling position means that the vehicle is traveling in a state where there is no fear of contact with the upper and lower nozzles.

Looking at the threads and scratches, both the comparative example and the example are "OK". “OK” in the thread and the scratch means a state where the thread and the scratch are not attached to the magnetic tape.

Looking at the tape shift, the comparative example shows "N
G ", whereas the embodiment is" OK ". "NG" in the tape shift refers to a case where the magnetic tape shifts during running and breaks in the tape. "O
"K" is a case where the magnetic tape travels without shifting. Therefore, while the conventional floating dryer caused tape breakage due to tape shift, in the drying equipment according to the present invention, stable running was confirmed without tape breakage due to tape shift.

Looking at the amount of bending, in the comparative example, +52.
Although it is in the range of 5 to -52.5 mm, in the embodiment, as shown in FIG. 4, it is in the range of +9.5 to -7.5 mm. The value of the amount of bending is desirably in the range of +10 to -10 mm. Therefore, the comparative example does not satisfy this condition, but the example satisfies this condition.

Next, when the thickness of the magnetic tape is 20 μm,
14 μm, 12 μm, 9 μm, 7.5 μm, 7.2 μm
The same test as described above was carried out for the sample. Then, based on the test results and the test results described above, Table 2 shows whether or not the magnetic tape of each thickness can be run.

[0056]

[Table 2]

In the evaluation of feasibility of running in Table 2, "O" indicates that
A magnetic tape that can run 100%. “△” indicates that the tape is sometimes broken due to the tape shift. “×” indicates that the vehicle cannot run at all.

As can be seen from Table 2, when the thickness of the magnetic tape is 11 μm, 9 μm, and 7.5 μm, the tape breakage sometimes occurs due to the tape shift in the conventional floating dryer. The equipment can run 100%. A magnetic tape having a thickness of 7.2 μm cannot run at all with a conventional floating dryer, but can run 100% with the drying equipment according to the present invention.

As described above, according to the embodiment of the present invention, the guide tape is provided below the upper nozzle, and the magnetic tape is supported by the guide roll by bringing the guide roll into contact with the lower surface of the magnetic tape. To run. Thereby, the shift of the magnetic tape and the nozzle contact can be prevented.
That is, by inserting the guide roll into the floating dryer, the problems of the tape shift and the nozzle contact of the undried magnetic tape, which have been conventionally difficult, are solved. That is, the magnetic tape, which conventionally undulates like a wave in the tape width direction, can be stably run by being pressed by the guide roll. As a result, it is possible to reduce the stop time and improve the length yield.

In addition to running thin films which have been impossible to run so far, continuous running at a production speed is possible even for curved films, and the average speed can be increased. Further, since it is no longer necessary to perform nozzle dirt check in a hot place at the time of product changeover, which has been conventionally performed, the burden on the operator and the number of man-hours can be reduced. In addition, energy can be saved by driving the guide roll using hot air from the upper nozzle.

In the above embodiment, the magnetic tape has been described as an example of the wide sheet, but the wide sheet is not limited to this magnetic tape. In addition, the drying device according to the present invention can be applied to any sheet-like material such as paper. In addition, the present invention is not limited to the above-described embodiment, but can adopt various other configurations without departing from the gist of the present invention.

[0062]

The present invention has the following effects. By providing a guide roll under the upper nozzle and bringing the guide roll into contact with the lower surface of the wide sheet, shift of the wide sheet and contact with the nozzle can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the invention relating to a drying facility.

FIG. 2 is a view showing a guide roll used in the drying equipment of the present invention.

FIG. 3 is a diagram showing a state in which the impeller of a guide roll is rotationally driven by hot air from an upper nozzle.

FIG. 4 is a diagram illustrating the concept of the amount of bending of a curved wide sheet.

FIG. 5 is a diagram schematically showing a conventional magnetic tape coating machine.

FIG. 6 is a diagram schematically showing the inside of a drying facility of a conventional magnetic tape coating machine.

[Description of Signs] 1 ‥‥ unwinding section, 2 ‥‥ base material, 3 ‥‥ wide sheet, 3a
{Upper surface, 3b} Lower surface, 4} Drying equipment, 5} Winding unit, 6} Upper nozzle, 7} Lower nozzle, 8} Guide roll, 9} Rectifier plate, 11} Coating Part, 12 ‥‥ impeller, 13 ‥‥ feather, 14 ‥‥ surface

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shinichi Numakura 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Satoru Satoru 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo No. within Sony Corporation (72) Inventor Keiji Sato 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo F-term within Sony Corporation (reference) 3L113 AA02 AA08 AB02 AB10 AC01 AC31 AC45 AC46 AC52 AC54 AC55 AC63 AC65 BA26 CA05 DA04 DA07 DA10 DA24 5D112 CC13 CC14 KK05

Claims (6)

[Claims] (A) In a drying facility having the following upper nozzle and lower nozzle: (A-1) The upper nozzle blows hot air onto the running wide sheet from the upper surface of the wide sheet. (A-2) The lower nozzle blows hot air onto the wide sheet from the lower surface of the wide sheet. (B) Drying equipment characterized by the following. (B-1) A guide roll is provided below at least one of the upper nozzles. (B-2) The guide roll contacts the lower surface of the wide sheet. 2. The drying equipment according to claim 1, wherein: (A) Impellers are provided at both ends of the guide roll. (B) The guide roll is driven to rotate by applying hot air blown from the upper nozzle to the impeller. 3. The drying equipment according to claim 2, wherein: (A) The following current plate is provided. (A-1) The current plate is located below the upper nozzle. (A-2) The rectifying plate is configured such that the hot air blown from the upper nozzle is
Make sure it hits the guide roll impeller. 4. The drying equipment according to claim 2, wherein: (A) The guide roll has the following first and second impellers at both ends. (A-1) The first impeller and the second impeller have wings attached at the same pitch. (A-2) The wings of the first impeller and the wings of the second impeller are mounted so as to be shifted from each other by a half pitch. 5. The drying equipment according to claim 1, wherein: (A) The guide roll has conductivity. 6. A magnetic tape manufacturing apparatus characterized by the following. (A) The drying equipment according to claim 1, 2, 3, 4, or 5 is included. (B) The wide sheet is a magnetic tape.