JPH01263985A - Tape cassette - Google Patents

Abstract

PURPOSE:To secure the running property and electromagnetic conversion characteristics of a magnetic tape by providing a hygroscopic layer at, at least, part of the inner surface of a tape cassette in the vicinity of the magnetic tape stretched between both reels. CONSTITUTION:A hygroscopic layer 13 is provided at, at least, part of the inner surface of a tape cassette in the vicinity of a magnetic tape 12 stretched between both reels 8. Therefore, even if the outside air enters into the cassette through a clearance of the cassette and increases the inside humidity of the cassette when the temperature and humidity of the outside environment of the cassette abruptly change, the hygroscopic layer 13 acts to suppress the humidity increase to an extremely low level and as a result, the water film formed on the surface of the magnetic tape 12 is made thinner and dew condensation does not take place. Thus the running property and electromagnetic conversion characteristics of the magnetic tape can be secured.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a tape cassette for storing a metal-based magnetic tape suitable for high-density magnetic recording.

BACKGROUND OF THE INVENTION Magnetic recording has made remarkable progress in recent years, and both areal and volumetric recording densities continue to improve.

This improvement in recording density, which is expected to continue in the future, will require
Ferromagnetic metal powder, Co-Ni-○ obliquely deposited film.

It is necessary to put into practical use magnetic tapes whose magnetic recording layers are made of metal magnetic materials such as Co-Cr sputtered films, and it is necessary to make the magnetic recording layers ultra-smooth and to improve the deterioration in handling properties caused by thinning the overall thickness of the tapes. In order to prevent signal defects from increasing due to external factors, the use of highly precise, highly functional, and well-sealed tape cassettes has been increasing. Publication No. 69-207422, Japanese Unexamined Patent Publication No. 1986
1-284829, JP-A-61-242323, JP-A-61-48481, JP-A-61-1
No. 18175, Japanese Unexamined Patent Publication No. 60-63779].

An example of the conventional tape cassette mentioned above will be described below with reference to the drawings.

FIG. 3 shows an enlarged sectional view of a conventional tape cassette. In Fig. 3, 1 is the cartridge body, 2
3 is a reel, 3 is a wound magnetic tape, 4 is a front lid, 5 is a back lid, and 6 is a magnetic tape pulled out to the lid portion.

The operation of the conventional tape cassette constructed as described above will be described below.

First, the front lint 4 and the back lid 5 have a structure that opens so that the internal magnetic tape can be taken out only when the tape cassette is inserted into the magnetic recording and reproducing device. It has a structure that always closes when it is extended.

Due to the effect of such an opening/closing structure, the magnetic tape in a stored state is configured to be sealed inside the cartridge main body or inside the movable lid part. This sealing effect prevents dust, contaminant molecules, water droplets, etc. in the air from adhering to the magnetic tape and deteriorating it, thereby increasing the reliability of high-density magnetic recording.

Problems to be Solved by the Invention However, with the degree of sealing obtained by the above-described configuration, it is not possible to completely prevent outside air from flowing into the tape cassette, and therefore, the actual damage described below occurs. For example, if there is high humidity from the gap in the movable lid, sometimes S02. Outside air containing highly corrosive gases such as C12゜Nox2 enters the tape cassette, forming a thick water film and causing condensation, resulting in poor tape running, inability to run, increased dropouts, and clogging. Problems such as the occurrence of actual damage such as the occurrence of the phenomenon of damage, and the degree of actual damage being exacerbated especially with thin tapes, and problems similar to those described above may be seen when using the tape after storage depending on the storage conditions, but improvements are needed. It was rare.

The present invention was made in view of the above circumstances, and provides a tape cassette with improved protection against sudden changes in external factors.

Means for Solving the Problems In order to solve the above-mentioned problems, the magnetic recording medium of the present invention includes a magnetic tape having a magnetic recording layer made of a metal magnetic material arranged between two reels, and a winding of the magnetic tape. The present invention is a tape cassette that stores two reels with a moisture absorption layer provided at least on a part of the inner surface of the tape cassette in the vicinity of the magnetic tape stretched between the two reels.

Operation The present invention has the above-described structure, and even when the temperature and humidity of the environment outside the tape cassette suddenly changes, and when outside air enters the tape cassette through the gap in the tape cassette and causes an increase in internal humidity, The moisture absorbing layer works to suppress the rate of increase in humidity to a very low level, thinning the water film that forms on the tape surface and preventing dew condensation from reaching a state of condensation. This means that the magnetic recording and reproducing performance can be maintained even during repeated storage and actual use.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an enlarged sectional view of a tape cassette according to an embodiment of the present invention. In Figure 1, 7 is the cartridge body, 8
9 is a reel, 9 is a wound magnetic tape, 10 is a front lid, 11 is a back lid, 12 is a magnetic tape pulled out to the lid portion, and 13 is a moisture absorption layer.

The cassette used was designed based on the 8 mm video standard, and the parts with the moisture absorbing layer, including those in the examples described later, were made of ABS resin, and the sample tape was made of polyethylene terephthalate film with a thickness of 7 μm. , diameter 100
15 pieces/(μm) of Al2O2 fine particles of A were arranged, and 3X10 (Torr) of Co-Ni (Co: B Owt%) was placed along a cylindrical can with a diameter of 1 m at an incident angle range of 90 degrees to 40 degrees. This is an 8 mm tape on which a magnetic recording layer obtained by vapor-depositing 16 μm of Q in oxygen is disposed, and 60 layers of perfluorostearic acid are disposed on the magnetic recording layer.

The cassette conditions of each example and comparative example and the results of the environmental cycle test are shown together.

Environmental test: 80℃ s o % RH and 5℃, 80%
After reciprocating the RH every 2 hours, judgment was made by visually observing the reproduced images using an 8 mm video.

There were two evaluation environments: 20° C. 60% RH and 6° C. 80% RH, and the number of evaluations was 1 condition and 5 points, of which the worst case was representative.

Next, a second example will be described in which polyamide was deposited on the inner surfaces of the front lid and back lid by sputtering and a cycle test was conducted.

FIG. 2 shows the results of preparing lids with varying sputtering times and varying film thicknesses, and examining the number of cycles at which dropout increased by 10 times the initial value. The cycle conditions were 20'C 80% RH and 6°C 80% RH, each environment contained 160p, p, m sulfur dioxide gas, and the round trip was performed every 3 hours, and the measurement was carried out at 20'C 50%.
These are the results obtained from RH to eo%RH. The adhesion to the inner surfaces of the front lid and battery lid was masked, and both were 8d for comparison.

As can be seen from Fig. 2, the effect is better when the coating is applied to the side facing the magnetic recording layer of the magnetic tape, that is, the fluorocarbon layer side, and if the coating is done at a thickness of 0.2 μm, It can be seen from this figure that the protection performance is 1Q times higher than that of the conventional example without adhesion, and that reliability is improved by preferably disposing it on both lids.

More preferably, by arranging it on the inner surface of the upper no.-f and the lower no.-f at a portion that is in contact with the magnetic recording layer, it is natural that higher reliability can be obtained, but it is also economical. In addition, under actual use conditions, conditions are usually not the same as the model cycle conditions, but are a combination of them. Therefore, it is preferable to carry out an optimal design, taking into account whether the usage is exact or not. It can be said.

In the above example, Co-N i-0 was used for the magnetic recording layer, but the same effect can be obtained for a Co-Cr perpendicular magnetization film, a metal powder-containing resin film, etc. There are no restrictions on the material, and γ
-Alumina, Gel Seronon.

PMMA, commercially available synthetic paper for moisture absorption purposes, cloth, sheet, etc. are used.

Effects of the Invention As described above, according to the present invention, by disposing a moisture absorption layer near the magnetic tape stretched between reels in a tape cassette, sudden changes in the external environment can be internally compensated for. By doing so, the degree of water film formation and dew condensation can be significantly suppressed, and there is an excellent effect that not only the runnability of the thin tape can be ensured but also the electromagnetic conversion characteristics can be ensured both in the short and long term.

[Brief explanation of the drawing]

Fig. 1 is an enlarged sectional view of the main parts of a tape cassette according to an embodiment of the present invention, Fig. 2 is a characteristic diagram showing the results of a cycle test according to the same embodiment, and Fig. 3 is an enlarged view of the main parts of a conventional tape cassette. FIG. 7...Cartridge body, 8...Reel, 9...Wound magnetic tape, 10...
...Front lid, 11...Back lid, 1
2...Magnetic tape pulled out to the lid section, 13
... Moisture absorption layer. Name of agent: Patent attorney Toshi Isamu Nakao and 1 other person7-
Cartridge body 8 ・-・Re-Russo--・-8 Contained production air Teig 10--・-7 Rosoto l/、Sort
Do 11 ・−〜 Buzz Rit
Do Ie -・-17, throat part 1; 1j 9 pieces of magnetic tag 13-

Claims (1)

[Claims] A tape cassette that stores a magnetic tape having a magnetic recording layer made of a metal magnetic material disposed between two reels, and two reels wound with the magnetic tape, the tape cassette having at least a span between both reels. A tape cassette characterized in that a moisture absorption layer is provided on a part of the inner surface of the tape cassette near the magnetic tape.