JP2615782B2 - Data cartridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a data cartridge,
More particularly, the present invention relates to a data cartridge provided with a drive belt having excellent characteristics.

[Summary of the Invention]

According to the present invention, in a data cartridge in which a magnetic tape is run by a drive belt, the drive belt is made of a thermoplastic elastic body containing a non-magnetic pigment, and defines a surface roughness of a contact surface with the magnetic tape. Data cartridge that can prevent the relaxation of the elastic stress of the drive belt, improve the surface properties, improve the running properties of the magnetic tape and the contact characteristics with the magnetic head, and prevent the occurrence of errors and dropouts It is intended to provide.

[Conventional technology]

Conventionally, as shown in FIG. 2, a drive belt (4) wound around a drive roller (1) and a pair of corner rollers (2) and (3) is taken up by a take-up reel (5) and a supply reel (6). Of the magnetic tape (7) between the reels (5) and (6) by the driving of the drive belt (4) by pressing against the outer peripheral side (magnetic layer surface) (7a) of each bundle of magnetic tapes (7). 2. Description of the Related Art There is known a data cartridge adapted to run.

In the data cartridge, the drive belt (4) plays a very important role in running the magnetic tape. That is, when running the magnetic tape (7), the drive belt (4) is moved to the outer peripheral side (the magnetic layer surface) of each magnetic tape (7) bundle of the take-up reel (5) and the supply reel (6) as described above. (7a) by directly contacting the drive belt (4) with the pressing force of the drive belt (4), the drive belt (4) and the magnetic tape (7).
And the frictional force with the magnetic layer surface (7a).

Therefore, when the frictional force and the pressing force of the drive belt (4) are appropriately maintained, a very stable contact is achieved between the drive belt (4) and the magnetic tape (7). The running of the magnetic tape is stabilized, the proper tape tension is maintained, and the stable contact between the magnetic tape and the magnetic head is achieved.

[Problems to be solved by the invention]

However, the drive belt (4), which plays a very important role in the data cartridge as described above, becomes fatigued with the passage of time, and the flattening of the contact surface of the drive belt (4) with the magnetic tape (7) is difficult. As a result, the tension of the drive belt (4) is relaxed, and the frictional force between the drive belt (4) and the magnetic tape (7) and the pressure contact force of the drive belt (4) are reduced.

As a result, the runnability of the magnetic tape becomes extremely unstable, causing poor reproduction, and the contact characteristic between the magnetic tape and the drive belt is deteriorated. The reel is taken up on the reel while being held, which causes problems such as disturbance of the winding of the magnetic tape and furthermore, the drive belt comes off the reel.

In view of the above, the present invention has been proposed in view of the above-described conventional situation, and it is intended to prevent the relaxation of the elastic stress of the drive belt, improve the surface property, and improve the running property of the magnetic tape and the contact property with the magnetic head. It is an object of the present invention to provide a data cartridge capable of improving the data quality and preventing occurrence of an error or dropout.

[Means for solving the problem]

The inventor of the present invention has achieved the above-mentioned objects and has conducted intensive studies.As a result, the drive belt is made of a thermoplastic elastic material containing a non-magnetic pigment and the surface roughness of the contact surface with the magnetic tape is regulated. Thus, the inventor has found that the above object can be achieved.

The present invention has been made based on the above findings. In a data cartridge, the data cartridge is made of a thermoplastic elastic material containing 1 to 10% by weight of a non-magnetic pigment, and has a surface roughness Ra of 0.5 to 10 in contact with a magnetic tape. The present invention is characterized in that a driving belt of 10 μm is used.

Here, the thermoplastic elastic body constituting the drive belt is easy to process at high temperatures, has large elongation, has extremely high durability under repeated loads, and has excellent wear resistance and electrical insulation properties. It is. Such a thermoplastic elastic material has a glass transition temperature of 0 ° C. or less (100% modulus 80 to 180 kgf /
cm ² ), elongation at break 300-600%, number average molecular weight 50,000-1500
Any material may be used as long as it satisfies conditions such as 00, and examples thereof include copolymers of polyester urethane, polyether urethane, polycarbonate urethane, polyester polyether, styrene butadiene, and the like.

In addition, as the thermoplastic elastic body, in addition to those described above, the affinity of the non-magnetic pigment for adjusting the surface properties and the like of the drive belt is improved, the interface between the non-magnetic pigment and the resin is reinforced, and the physical properties of the drive belt are improved. For the purpose of improving the relaxation of the tension, for example,-
A resin into which a polar group such as SO ₃ Na or —COOH is introduced may be used.

Further, after being processed as a drive belt, it is cross-linked to form a fibrous material (if cross-linked in a mesh shape, it becomes a fibrous shape in order to lose the properties of a viscoelastic body). The electron beam-curable resin and the ultraviolet-curable resin described above can also be used as the thermoplastic elastic body constituting the drive belt.

Various non-magnetic pigments are added to the above-mentioned thermoplastic elastic body in order to make the surface properties of the contact surface with the magnetic tape and the characteristics of the drive belt itself desirable when used as a drive belt.

As such a nonmagnetic pigment, any pigment may be used as long as it is uniformly dispersed, has a large interaction with the resin, improves the physical properties of the drive belt, and has an effect of suppressing a decrease in tension. Carbon black, graphite, glass fiber, silica, alumina, chromium oxide,
Examples include titanium oxide and calcium carbonate. In addition, when the electric resistance is high only with the thermoplastic elastic body, the charge amount becomes large and causes a discharge noise. Therefore, it is preferable to use carbon black as the nonmagnetic pigment to be added.

These nonmagnetic pigments may be subjected to a surface treatment with a silane coupling agent or a titanate coupling agent for the purpose of improving the dispersibility in the thermoplastic elastic material.

Here, the nonmagnetic pigment is preferably added at a ratio of 1 to 10% by weight in the thermoplastic elastic material. If the amount of the non-magnetic pigment is 1% by weight or less, the effect of adding the non-magnetic pigment cannot be obtained. If the amount is 10% by weight or more, the magnetic tape may be damaged or powder may fall off. Therefore, by adding the non-magnetic pigment in the thermoplastic elastomer at a ratio of 1 to 10% by weight, the adhesion of the drive belt is small and the charge can be suppressed.

The drive belt obtained by adding the non-magnetic pigment in the thermoplastic elastic body as described above, the surface of the contact surface with the magnetic tape preferably has a surface roughness Ra in the range of 0.5 to 10 μm. . In the present invention, the center line average roughness (JIS B 0601) is represented as the surface roughness Ra. The surface roughness of the contact surface of the drive belt with the magnetic tape has a very important meaning. That is, in the data cartridge, the drive belt is made to run the magnetic tape by directly contacting the magnetic tape. Therefore, when the contact surface of the drive belt with the magnetic tape is too smooth, high temperature, high Adhesion to the magnetic layer of the magnetic tape due to adhesion occurs under wet conditions, and in severe cases, the magnetic layer peels off and causes dropout. Also, if the contact surface of the drive belt with the magnetic tape is too rough, the magnetic layer surface of the magnetic tape may be scratched or fall off, resulting in dropout or reading error.

For the reasons described above, the most excellent runnability, the surface roughness of the contact surface of the drive belt with the magnetic tape is 0.5 to 10 μm as the range in which the characteristics of the magnetic tape can be exhibited.
m.

By the way, for the drive belt, a sheet having a predetermined thickness is manufactured using the thermoplastic elastic body to which the above-mentioned nonmagnetic pigment is added. Then, the sheet is punched as a ring of a predetermined size, and is stretched about 1.5 to 2.5 times in a high temperature state. Then, when the cartridge is mounted on the data cartridge, it is further stretched to about 1.1 to 2.0 times, and is mounted around the drive reel and the corner reel.

The drive belt preferably has a processed thickness of about 100 to 200 μm. If the thickness of the belt is less than 100 μm, it is too thin, and the deterioration of the tension due to the diametral speed becomes faster,
If the thickness is 200 μm or more, the tape speed fluctuation is deteriorated.

[Action]

By using a thermoplastic elastic body as a material of the drive belt, stress relaxation under repeated load can be prevented, and durability can be improved.

In addition, by adding a non-magnetic pigment to the thermoplastic elastic body, the surface roughness of the contact surface with the magnetic tape can be adjusted to a desired value, and adhesion to the magnetic tape is suppressed.

〔Example〕

Hereinafter, embodiments of the present invention will be described, but it goes without saying that the present invention is not limited to these embodiments.

Example 1 A sample drive belt was manufactured by the following method using sample resin 1 having the characteristics shown in Table 1.

That is, a compound was prepared by adding 2% of carbon to the sample resin, and this was made into a film using a T-die.

This was punched into a predetermined ring, and stretched in hot water at 70 ° C. so that the outer diameter became 300 mm, to obtain a sample drive belt.

Examples 2 to 5 In the same manner as in Example 1, sample drive belts were produced using Sample Resins 2 to 5 shown in Table 1.

Comparative Example 1 In the same manner as in Example 1, a sample drive belt was manufactured using the sample resins 6 shown in Table 1.

Using these sample drive belts, the stress relaxation characteristics of the drive belt were examined. The stress relaxation characteristic is obtained by elongating the sample driving belt with a constant stress in hot water at 60 ° C. and expressing the relaxation rate per hour.

The result is shown in FIG. In addition, in FIG.
Is indicated by 、, Example 2 is indicated by ×, Example 3 Δ is indicated, Example 4 is indicated by ◎, Example 5 is indicated by □, and Comparative Example 1 is indicated by ●.

As is clear from the results, the glass transition temperature is 0 ° C.
A drive belt made of a sample resin having the following and a 100% modulus in the range of 80 to 180 kgf / mm ² exhibited good characteristics with little deterioration of stress relaxation.

Example 6 A compound was prepared by adding 2% of carbon to polyurethane (manufactured by Nippon Polyurethane Co., Ltd., PP25M).
A film was formed using a die.

This was punched into a predetermined ring and stretched in hot water at 70 ° C. so that the outer diameter became 300 mm. The surface roughness of this belt was 1.3 μm. This belt was used as a sample drive belt for the data cartridge.

Then, as shown in FIG. 2, the sample driving belt produced as described above was mounted on a data cartridge by being wound between a drive roller (1) and a pair of corner rollers (2) and (3). The drive belt (4) mounted in this manner is connected to the magnetic tapes (7) of the take-up reel (5) and the supply reel (6).
The magnetic tape (7) runs between the reels (5) and (6) by running the drive belt (4) while being pressed against the outer peripheral side (magnetic layer surface) (7a) of the bundle. It has become.

Example 7 A sample driving belt for a data cartridge was prepared in the same manner as in Example 6 except that the amount of carbon used in Example 6 was changed to 6%. Then, a driving cartridge was attached in the same manner as in Example 6 to produce a data cartridge.

Comparative Example 2 to Comparative Example 3 The sample drive belt of the data cartridge was manufactured in the same manner as in Example 6 except that the amount of carbon used in Example 6 was 0% (Comparative Example 2) and 0.3% (Comparative Example 3). And Then, a driving cartridge was attached in the same manner as in Example 6 to produce a data cartridge.

Comparative Examples 4 to 7 0% (Comparative Example 4), 0.3% (Comparative Example 5), 2% (Comparative Example 6), 6% (Comparative Example 7) in polyurethane (PP25M manufactured by Nippon Polyurethane Co., Ltd.) ) Was added to produce a compound, which was formed into a film using a T-die.

This was punched into a predetermined ring and stretched in hot water at 70 ° C. so that the outer diameter became 300 mm. The surface roughness of this belt was 0.03 μm. This belt was used as a sample drive belt for the data cartridge. And Example 6
A drive belt was attached in the same manner as in the above to prepare a data cartridge.

An adhesion test between the magnetic layer and the sample drive belt was performed on each of the data cartridges manufactured as described above.

The test was performed by leaving each of the above-mentioned sample driving belts mounted on a data cartridge for one week under the conditions of 50 ° C. and 80% RH, and then measuring the starting torque.

 Table 2 shows the results.

As is apparent from Table 2, in the data cartridge of the embodiment in which a predetermined amount of carbon is added and the surface roughness is within a predetermined range, the starting torque is small, and the magnetic tape runs smoothly and with high stability. No dropout or error occurs because there is no sticking between the magnetic tape and the drive belt. On the other hand, in the comparative example in which the amount of carbon added and the surface roughness were not within the predetermined ranges, the starting torque was large and smooth running could not be expected, and the magnetic layer adhered to the drive belt. Peeling occurred, resulting in dropouts and errors.

〔The invention's effect〕

As is clear from the above description, in the present invention,
By using a thermoplastic elastomer and defining the content of non-magnetic pigment to be added and the surface roughness of the contact surface between the magnetic tape and the belt, the stress relaxation characteristics of the drive belt under repeated loads can be improved. In addition, the adhesiveness between the magnetic tape and the drive belt can be suppressed.

Therefore, it is possible to provide a data cartridge which can ensure the running stability of the magnetic tape and can secure the contact with the magnetic head.

[Brief description of the drawings]

FIG. 1 is a characteristic diagram showing stress relaxation characteristics of a sample drive belt. FIG. 2 is a partial schematic perspective view showing an example of the data cartridge. 1 Drive roller 2, 3 Corner roller 4 Drive belt 7 Magnetic tape

Claims (1)

(57) [Claims] 1. A surface roughness of a contact surface with a magnetic tape, comprising a thermoplastic elastomer containing 1 to 10% by weight of a nonmagnetic pigment.
A data cartridge using a drive belt having a Ra of 0.5 to 10 μm.