JPS58160845A - Apparatus for exposure test of magnetic recording medium - Google Patents

Abstract

PURPOSE:To obtain uniform results of a corrosion test of each sample having no variance of effects in an atomosphere for the sample, by providing a reticulate vent hole on each surface of a vessel housing a magnetic recording medium and performing an exposure test under all kinds of the atmosphere. CONSTITUTION:An apparatus is constituted so that mixing of foreign matters such as fine dust (sand, ash, soot, metallic powder) is prevented and also, atmosphere gas is ventilated uniformly for a sample by providing a window 6 made of duplicated fabrics having 0.2mm. mesh which is woven in plane fabrics by a single yarn of a natural fiber on all six faces of the apparatus. The fabric woven in the plane fabric by the single yarn is of a double folded construction and fine dust is trapped easily by this fabric. A sample in which the magnetic recording medium of a metallic thin film is fixed on a slide glass by an adhesive tape, is taken in a testing apparatus and is covered and fixed. Hereafter, it is observed by an optical microscope after leaving as it is for a fixed period under various kinds of enviromental atmosphere and it is examined how much the sample has corrosion resistance in each atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exposure testing device for magnetic recording media, which is used to test, for example, metal thin film magnetic recording tapes under various atmospheres.

Vacuum deposition and sputtering of thin films of iron, cobalt, nickel, or alloys containing these as main ingredients.

Metal thin film type magnetic recording tapes formed on a substrate film by methods such as ion blating or plating, or metal powder type magnetic recording tapes in which these metal powders are bonded with a resin binder, are made using conventional iron oxide as a living body. Unlike ordinary coated tapes that combine ferromagnetic powder with a resin binder, they are susceptible to corrosion in high humidity or corrosive gases.

Therefore, the surface of metal thin film type or metal powder type magnetic recording tape is stabilized by oxidation using glow discharge or anti-rust treatment such as extremely thin resin coating, but this method is not fully satisfactory in practical use. Currently, it is difficult to obtain items in good condition.

In particular, many regions of Japan have a rainy season, which is particularly hot and humid, creating extremely bad conditions from the perspective of metal corrosion, and in fact, many complaints about corrosion of various metal parts occur during this period. Tend. Furthermore, our country is surrounded by the sea, and residents near the coast are constantly exposed to a highly corrosive atmosphere containing salt. Furthermore, Japan is a volcanic country, and hot springs and volcanic gases are generated in many areas, and in many cases, hydrogen sulfide (H2S), sulfur dioxide (802), ammonia (
There are industrial areas in many areas that generate corrosive gases such as NHs, and some of these areas may generate various corrosive gases and dust. Furthermore, even in ordinary homes, depending on the location, there may be cases where people are exposed to a strong corrosive atmosphere. For example, in the kitchen, there is a chlorinated atmosphere, a vinegar atmosphere, a deteriorating cooking oil atmosphere, and a closet, where there is high humidity, wood plywood, and gases generated. or,
Condensation from air conditioning and combustion gas from kerosene heaters also increase corrosivity.

As is well known, iron corrodes even under normal environments, while nickel and cobalt have superior corrosion resistance compared to iron, but corrode under the aforementioned environments. Especially unlike metal plates, vacuum evaporation, sputtering, and ion plating.

Metal thin films made by one method, such as plating, are generally more active than metal plates and tend to be more susceptible to corrosion.

Magnetically recorded cassette tapes, whether audio or video recording, must be able to be stored for long periods of time without corrosion or deterioration. For example, for long-term visual records of people's childhood, corrosion resistance of 10 to 20 years would be required. vapor deposition tape.

If left in various atmospheres, it may corrode in a relatively short period of time. For example 60~60”Ch relative humidity 90%
It is said that corrosion will occur in a few weeks in an atmosphere like this, and even if it is left indoors during the rainy season, corrosion products in the form of white specks may be observed within a few months. In order to prevent this type of deterioration due to corrosion, oxidation or coating is performed on the surface layer using glow discharge, but it is necessary to properly understand the degree of corrosion resistance in various atmospheres. It is.

To this end, it is necessary to perform various accelerated corrosion tests to evaluate corrosion resistance, but even if accelerated tests are performed, it is often difficult to estimate the service life.

The best method is to perform long-term exposure tests in various practical atmospheres to estimate the lifespan.

By linking it with accurate monitoring results of various atmospheres, even more reliable life estimation becomes possible.

Here, a conventionally used exposure test apparatus will be explained below. That is, an exposure test was conducted under various environmental atmospheres using a device in which several holes were punched in the side of a general slide glass case to provide ventilation for gas, etc. FIG. 1 shows a conventional test device. In the figure, 1 is a ventilation hole, 2 is a sample placed near the ventilation hole 1, 3 is a sample placed near the center, 4 is a slide glass case, and 6
is the lid of the slide glass case 4.

In a conventional test apparatus with such a configuration, when various atmospheric gases are allowed to flow in through the vent hole 1, the atmospheric gases affect the sample 2, but the sample 2 cuts off the atmospheric gases that have flowed in, and
It has little effect on sample 3. For this reason, the influence of the atmosphere on the sample near the ventilation hole and the center of the device is extremely large. There was a phenomenon in which the atmosphere had little effect on nearby samples. For this reason, the corrosion resistance of each sample was different, and there was a drawback that it was difficult to compare the corrosion resistance between each sample.The present invention aims to eliminate the above-mentioned drawbacks of the conventional method, and the following drawings are used to describe the present invention. An example thereof will be explained.

FIG. 2 shows the external appearance of the test device according to the invention.

In this case, all six sides of the device were plain woven with single yarns of natural fibers. Window 6 made of double woven fabric with an opening of 0.2 mm
By providing a filter, fine dust (sand, ash, soot,
This structure prevents the introduction of foreign substances such as metal powder) and allows atmospheric gas to be evenly vented to the sample. The woven fabric is plain woven with single yarns and has a double layer structure. ``This makes it easier to trap fine dust etc. However, if the fabric is made of two or more layers, the trapping of fine dust increases, but the spatial space of the window e becomes smaller, which has the effect of reducing the inflow and outflow of atmospheric gas and the like.

Also, among the single yarns of natural fibers, cotton yarns are suitable because they generate less gas than single yarns, do not contain chlorine, etc., are inexpensive, and are made of a soft material.

As for the count of the single yarn, a count of 30 to 42 is suitable because it is suitable for the space of the window 6 and is inexpensive.As a material for the window, for example, commercially available gauze is suitable. Gauze does contain a small amount of chlorine.

Rinse with pure water 3 to 4 times to remove chlorine. Furthermore, gauze is convenient to use because it is inexpensive and easy to handle.

After the exposure test, the atmosphere during the exposure test can be confirmed by analyzing the cotton fabric that is the window of this device.

Reference numeral 7 denotes legs, and this configuration allows atmospheric gas to flow into and out of the main body from the lower part. Reference numeral 8 denotes a lid, which is configured to be opened and closed above the main body 9. 1o is a stopper for fastening the main body S and the lid 8. It should be noted that the constituent materials of this device are preferably made entirely of synthetic resin, since it is used in extremely corrosive environments 1, such as hot spring areas. It is also required that no corrosive gas is generated from the resin.

FIG. 3 is a sectional view of the device. As shown in the figure, a sample 11 in which a metal thin film type magnetic recording medium is fixed onto a glass slide with adhesive tape is supported in a main body 9 on a sample fixing table 12.

Further, 13 is a hinge for connecting the main body 9 and the lid 8.

FIG. 4 shows an exploded view of the window section of the device. In the figure, 1
4 is a mesh, 16 is an outer frame of the mesh 14, and 16 is a fixed frame of the mesh 14. The MEC 14 is configured to be sandwiched between the outer frame 16 and the fixed frame 16.

FIG. 6 shows the external appearance of the sample fixing table, and 17 is a groove for fixing a slide glass on which a sample is added (the groove width is suitably 2 to 2.2 mm). The fixing table 12 has a structure that allows atmospheric gas to be evenly vented to the sample when the sample is fixed.

Next, how to conduct an exposure test using this test device
1: Explain.

A sample of a metal thin-film magnetic recording medium fixed to a slide glass with adhesive tape was placed in a test device, fixed with a lid, and left in various environmental atmospheres for a certain period of time, and then observed with an optical microscope to determine whether the sample was different from each other. Examine the degree of corrosion resistance in the atmosphere. In addition, when using this device, avoid places where it may be exposed to rainwater, and provide suitable shelter.
Test by leaving it inside or indoors.

Compared to conventional devices, the device according to the present invention has less variation in the influence of the atmosphere on the sample, can obtain uniform corrosion test results for each sample, can simultaneously monitor various atmospheres, and has improved reliability. High life estimation becomes possible.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional test device, FIGS. 2 and 3 are a perspective view and a sectional view of a test device according to the present invention, respectively, and FIG. 4 is an exploded perspective view of a window that forms the main part of the test device. Figure, 6th
The figure is a perspective view of a sample fixing table, which is another essential part of the test apparatus. 6...window, 8...lid, 9...
- Main body, 10... Clasp, 12... Sample fixing stand, 14... Metsch. 17...Fixing groove. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Brush 9 Garden 6' Inf
jS3 Figure 4

Claims (1)

[Claims] An exposure test device for magnetic recording media, comprising a container for storing a magnetic recording medium and performing exposure tests under various atmospheres, the container having mesh-like ventilation holes on each side. .