JPH01237983A - Data cartridge - Google Patents

Abstract

PURPOSE:To prevent an error and dropout from generating by being composed of a thermoplastic elastic body to contain the non-magnetic pigment of a prescribed weight % and using a driving belt in which the surface roughness of the contact surface of a magnetic tape is a prescribed range value. CONSTITUTION:In a data cartridge to travel a magnetic tape by a driving belt, a driving belt is composed of a thermoplastic elastic body to contain 1-10wt.% of the non-magnetic pigment and a surface roughness Ra of the contact surface of a magnetic tape is specified to be 0.5-10mum. Thus, the release of the elastic stress of the driving belt is prevented and a surface feature is improved. By improving the movement of the magnetic tape and the abutting characteristic of the magnetic tape, a data cartridge, which can prevent the error and the dropout from generating, can be obtained.

Description

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

[Summary of the invention]

The present invention provides a data cartridge in which a magnetic tape is run by a drive belt. By specifying this, it is possible to prevent the elastic stress of the drive belt from relaxing, improve the surface properties, improve the running performance of the magnetic tape and the contact characteristics with the magnetic head, and prevent the occurrence of errors and dropouts. The aim is to provide a data cartridge with a wide range of functions.

[Conventional technology]

Conventionally, as shown in Fig. 2, a drive belt (4) that is passed between a drive roller (1) and a pair of corner rollers (2) and (3) is connected to a pick-up reel (5) and a supply reel (6). The above-mentioned drive heel I is brought into pressure contact with the outer peripheral side (magnetic layer surface) (7a) of each magnetic tape (7) bundle.
- Each reel (5), (
A data cartridge is known in which a magnetic tape (7) is caused to run between (6) and (6).

In the data cartridge described above, 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 (magnetic layer surface) of each magnetic tape (7) bundle of the pick-up reel (5) and the supply reel (6) as described above. This is done by directly pressing the drive bell I-(7a).
This is caused by the pressure contact force (4) and the frictional force between the drive belt (4) and the magnetic layer surface (7a) of the magnetic tape (7).

Therefore, if the frictional force and pressure contact force of the drive belt (4) are maintained appropriately, very stable contact is achieved between the drive belt (4) and the magnetic tape (7). This stabilizes the running of the magnetic tape, maintains appropriate tape tension, and ensures stable contact between the magnetic tape and the magnetic head.

[Problem to be solved by the invention]

However, the drive belt (4), which plays a very important role in the data cartridge as mentioned above, becomes fatigued over time, and the contact surface of the drive belt (4) with the magnetic tape (7) becomes flattened. The tension of the drive belt (4) is relaxed, and the drive belt (4) and magnetic tape (7)
This results in a decrease in the frictional force with the drive belt (4) and the pressure contact force of the drive belt (4).

As a result, the running properties of the magnetic tape become extremely unstable, causing poor playback, and the contact characteristics between the magnetic tape and the drive belt deteriorate. Therefore, if the magnetic tape is repeatedly run in this state, the magnetic tape may become slack. Since the magnetic tape is wound onto a reel while being held, problems such as the winding of the magnetic tape being disordered and the drive belt coming off the reel occur.

Therefore, the present invention was proposed in view of the above-mentioned conventional situation, and it prevents the elastic stress of the drive belt from being relaxed and improves the surface properties, thereby improving the running performance of the magnetic tape and the contact characteristics with the magnetic head. The purpose of this project is to provide a data cartridge that can improve performance and prevent the occurrence of errors and dropouts.

[Means to solve the problem]

As a result of intensive research, the inventors of the present invention have determined that the above object can be achieved by constructing the drive belt from a thermoplastic elastomer containing a non-magnetic pigment and by specifying the surface roughness of the contact surface with the magnetic tape. We have come to the conclusion that the above objectives can be achieved.

The present invention has been made based on the above findings, and is a data cartridge made of a thermoplastic elastic material containing 1 to IO weight % of non-magnetic pigment, and the surface roughness Ra of the contact surface with the magnetic tape is 0. It is characterized by using a drive belt having a thickness of 5 to 10 μm.

Here, the thermoplastic elastic material that constitutes the drive belt is one that is easy to process at high temperatures, has high elongation, has very high durability under repeated loads, and has excellent abrasion resistance and electrical insulation properties. It is. Such a thermoplastic elastomer has a glass transition temperature of 0°C or less (100% modulus of 80 to 18
0 kgf/cat), elongation at break 300-600%,
Any material may be used as long as it satisfies conditions such as a number average molecular weight of 50,000 to 150,000, such as polyester urethane, polyether urethane, polycarbonate urethane, and polyester/polyether.

Examples include copolymers of styrene and butadiene.

In addition to the above-mentioned thermoplastic elastomers, we also improve the compatibility with non-magnetic pigments that adjust the surface properties of the drive belt, and strengthen the interface between the non-magnetic pigment and the resin, thereby improving the physical properties of the drive belt. For the purpose of improving tension relaxation, for example -5
It may also be a resin into which a polar group such as OJa or -COOH is introduced.

Furthermore, after being processed into a drive belt, it is cross-linked to form a fibrous material (if cross-linked in a 4M pattern, it loses its properties as a viscoelastic material, so it becomes a fibrous material) with a high molecular weight and improved tension. Electron beam curable resins and ultraviolet ray curable resins can also be used as thermoplastic elastic bodies constituting the drive belt.

Various non-magnetic pigments are added to the above-mentioned thermoplastic elastomer in order to obtain desired surface properties of the contact surface with the magnetic tape and properties of the drive belt itself when it is made into a drive belt.

Such a non-magnetic pigment may be any pigment as long as it is uniformly dispersed, has strong interaction with the resin, improves the physical properties of the drive belt, and has the effect of suppressing a decrease in tension. Carbon black, graphite, glass fiber.

Examples include silica, alumina, chromium oxide, titanium oxide, and calcium carbonate. Note that if the thermoplastic elastomer alone has a high electrical resistance, the amount of charge will increase and cause discharge noise, so it is preferable to use a carbon blank as the non-magnetic pigment to be added.

Further, these nonmagnetic pigments may be surface-treated with a silane coupling agent or a titanate camping agent for the purpose of improving dispersibility in a thermoplastic elastomer.

Here, it is preferable that the non-magnetic pigment described in item 2 is added in a proportion of 1 to 10% by weight in the thermoplastic elastomer. If the amount of non-magnetic pigment added is less than 1% by weight, the effect of adding the non-magnetic pigment cannot be obtained, and if it is more than 10% by weight, it may cause scratches on the magnetic tape, powder falling off, etc. Therefore, the non-magnetic pigment is contained in the thermoplastic elastomer in an amount of 1 to 10% by weight.
By adding it in a mirror combination, there is less adhesion of the drive belt and it is possible to suppress charging.

The drive belt obtained by adding a non-magnetic pigment to the thermoplastic elastomer as described above has a surface roughness Ra of the contact surface with the magnetic tape within the range of 0.5 to 10 μm. is preferred.

In the present invention, the surface roughness Ra is expressed as center line average roughness (JIS B 0601). The surface roughness of the contact surface with the magnetic tape in the drive belt has a very important meaning. In other words, in a data cartridge, the drive belt runs the magnetic tape by coming into direct contact with the tape.
Therefore, if the contact surface of the drive belt with the magnetic tape is too smooth, it may stick to the magnetic layer of the magnetic tape under high temperature and high humidity conditions, and in severe cases, the magnetic layer may become unrecognizable. This may cause dropouts. Furthermore, if the contact surface of the drive belt with the magnetic tape is too rough, the surface of the magnetic layer of the magnetic tape may be damaged or powder may fall off, resulting in dropouts or reading errors.

For the above reasons, the surface roughness of the contact surface of the drive belt with the magnetic tape should be set at 0.5 to IO as the range that provides the best running performance and exhibits the characteristics of the magnetic tape.
It was set as μm.

By the way, the above-mentioned drive belt is made into a sheet having a predetermined thickness using the above-mentioned thermoplastic elastomer added with the non-magnetic pigment. Then, the sheet is punched out into a ring of a predetermined size and stretched to about 1.5 to 2.5 times in a high temperature state. Then, when mounting the data cartridge, it is further stretched by 1.1 to 2.0 times and passed around the drive reel and corner reel.

The thickness of the drive belt after processing is preferably about 100 to 20 μm. This is because if the thickness of the belt is less than 100 μm, it is too thin and the tension deteriorates quickly due to the past, and if it is more than 200 μm, the tape speed fluctuation deteriorates.

[Function] By using a thermoplastic elastic body as the material for the drive belt, stress relaxation under repeated loads can be prevented and durability can be improved.

Further, 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 with the magnetic tape can be suppressed.

〔Example〕

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

A sample drive belt was produced by the following method using Sample Resin 1 having the properties shown in Table 1.

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

This was punched out into a predetermined ring and stretched in hot water at 70°C to an outer diameter of 300 mm to form a sample drive belt.

Table 1 A sample drive belt was produced using Sample Resin 2 to Sample Resin 5 shown in Table 1 in the same manner as in Example I.

,! A sample drive belt was produced using sample resin 6 shown in Table 1 in the same manner as in Example 1.

The stress relaxation characteristics of the drive belt were investigated using these sample drive belts. The stress relaxation property is expressed as a relaxation rate per hour when the sample drive belt is stretched under a constant stress in warm water at 60°C.

The results are shown in FIG. In Fig. 1, Example 1 is marked with ○, Example 2 is marked with ×, Example 3 is marked with △, and Example 4 is marked with ◎.
Example 5 is indicated by a 0 mark, and Comparative Example 1 is indicated by a * mark.

As is clear from this result, the glass transition temperature of the liquid is 0°C or lower, and the 100% modella is 80 to 180 kg.
A drive belt manufactured using a sample resin falling within the f/2 range showed good characteristics with little deterioration in stress relaxation.

Implementation - Yuj Polyurethane (manufactured by Nippon Polyurethane Co., Ltd., PP25M)
A compound was prepared by adding 2% carbon therein, and this was made into a film using a T-die.

This was punched out into a predetermined ring and stretched in hot water at 70°C to an outer diameter of 300mm.

The surface roughness of this belt was 1.3 μm. This belt was fastened to the sample drive belt of the data cartridge.

Then, as shown in Fig. 2, the sample drive belt produced as described above is passed between the drive roller (1) and the pair of corner rollers (2) and (3)*
It was loaded onto a data cartridge. The drive belt (4) installed in this way is attached to each magnetic tape (
7) The magnetic tape (7) is pressed between the reels (5) and (6) by driving the drive belt (4) in pressure contact with the outer peripheral side (magnetic layer surface) (7a) of the bundle.
The running is now scheduled to take place.

A sample drive 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 6%. Then, a drive belt was attached in the same manner as in Example 6 to produce a data cartridge.

0% counterfeit carbon used in Example 6 (Comparative Example 2),
A sample drive belt for a data cartridge was prepared in the same manner as in Example 6, except that 0.3% (Comparative Example 3) was used. Then, in the same manner as in Example 6, a data cartridge was produced by attaching a drive belt.

As a comparative example, Hokuenen polyurethane [Shiraki Polyurethane Co., Ltd.'A, PP25M]
Compounds were prepared by adding 0% (Comparative Example 4), 0.3% (Comparative Example 5), 2% (Comparative Example 6), and 6% (Comparative Example 7) of carbon to was used to make the film.

This was punched out into a predetermined ring and stretched in hot water at 70°C to an outer diameter of 300 mm.

The surface roughness of this belt was 0.03 μm. This belt was used as a sample drive belt for a data cartridge. Then, in the same manner as in Example 6, a drive belt was attached and a data cartridge was manufactured.

An adhesion test between the magnetic layer and the sample drive belt was conducted for each of the two data carts produced as described above.

The test was conducted by measuring the starting torque after leaving each of the sample drive belts described above in a data cartridge for one week at 50 DEG C. and 80% R11.

The results are shown in Table 2.

(Leaving space below) Table 2 As is clear from Table 2 above, in the example data cartridge in which a predetermined amount of carbon was added and the surface roughness was within a predetermined range, the starting torque was small and the magnetic tape It provides smooth and highly stable running, and since there is no adhesion between the magnetic tape and the drive belt, there are no dropouts or errors.

On the other hand, in the comparative example where the amount of carbon added and the surface roughness are not within the specified range, the starting torque is large and smooth running cannot be expected, and the magnetic layer sticks to the drive belt. Peeling occurred, resulting in dropouts and errors.

〔Effect of the invention〕

As is clear from the above explanation, in the present invention, a thermoplastic elastic body is used, and by specifying the content of non-magnetic pigment added thereto and the surface roughness of the contact surface between the magnetic tape and the belt. , it is possible to improve the stress relaxation characteristics of the drive belt under repeated loads and to suppress the adhesion between the magnetic tape and the drive belt.

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

[Brief explanation of the drawing]

FIG. 1 is a characteristic diagram showing the stress relaxation characteristics of the sample drive belt. FIG. 2 is a schematic perspective view showing an example of a data cartridge. ]...Drive roller 2.3...Corner roller 4...Drive belt 7...Magnetic tape Patent applicant Sony Corporation representative Patent attorney Koike Akioka Yamamura Sakae - Same Sao Koshirae

Claims (1)

[Claims] It is made of a thermoplastic elastomer containing 1 to 10% by weight of non-magnetic pigment, and the surface roughness Ra of the contact surface with the magnetic tape is 0.
Data cartridge using a drive belt that is 5-10 μm.