JPH09325698A - Water wetting detecting sheet and portable signal transmitter/receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily decide whether there is water leakage or not by providing the window part of a sheet-like supporting body bored with part consisting of a blank having water resistance to a window shape with a water-soluble film. SOLUTION: The sheet-like supporting body 1 consists of the blank having the water resistance and is partly bored with the window shape. The window part 2 of the sheet-like supporting body 1 bored with part consisting of the blank having the water resistance to the window shape is provided with the water-soluble film 3. Fixing of the water-soluble film 3 to the sheet-like supporting body 1 is executed by sticking the film to the sheet-like supporting body 1 in a state free from a sag. Then, the window part 2 is merely provided with the water-soluble film 3 and since the sheet-like supporting body 1 is not subjected to lining in the wetting detecting sheet, the water-soluble film 3 elutes by being eroded with water from both front and rear surfaces thereof. The water-soluble film 3 is deformed and is opened with holes by the dissolution of the water-soluble film 3 and, therefore, the decision as to whether there is the water leakage or not is made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to portable communication devices such as mobile communication terminals and pagers, and devices used outdoors such as cameras and video cameras that have been subjected to unauthorized use such as submersion in water or water. The present invention relates to a water wetting detection sheet and a portable transmission / reception device that can determine the history of whether or not it is.

[0002]

2. Description of the Related Art Mobile communication terminals, pagers, cameras,
Equipment used outdoors, such as video cameras, has a relatively high risk of getting wet with rain or splashing with water, so that some degree of water resistance is considered. However, it may be accidentally dropped in a puddle or dropped in a container filled with water, and the internal circuits may be wet with water, impairing the function as an electric product. In such cases, it is due to the carelessness of the user and is subject to paid repair.

However, it is difficult to determine whether the failure is caused by submersion in water or in the range of normal use, which sometimes causes a trouble.

Therefore, conventionally, a label having a water-soluble coloring layer is formed by directly coating a water-soluble coloring resin in which a coloring material such as a dye or a pigment is mixed, dissolved or dispersed in a water-soluble resin on a substrate sheet. Affix to the inside of the product in advance via an adhesive layer such as an adhesive, and if a failure occurs, check the label condition to see if the water-based ink is bleeding or discolored. The cause of the failure was determined by whether or not

[0005]

However, in the conventional label, when the colored layer is melted out due to water wetting, the water-soluble dye has penetrated into the inside of the paper which is the base sheet, and thus the decoloring rate. Is slow, the melted colorant penetrates into the base sheet and may be colored and the discoloration may not be clear, and when an ink manufactured using a cobalt-based or amine-based dye is used, it may become submerged due to discoloration of the ink. You can tell what you did, but if it dries, it will return to its original state and you will not be able to tell.
In addition, if there is a water resistant layer such as a support or a water resistant adhesive on the back of the water soluble film, water permeation will be slow, so with regard to instant water wetting, it will return to the original state if it dries and it will not be possible to judge. There was also.

Therefore, it is an object of the present invention to provide a water wetting detection sheet and a portable transmission / reception device which solve the above-mentioned drawbacks.

[0007]

In order to achieve the above object, the water wetting detection sheet of the present invention is constructed as follows.

That is, the water wetting detection sheet of the present invention is
The water-soluble film was provided on the window portion of the sheet-shaped support in which a part of the material having water resistance was pulled out like a window.

In the above invention, the water-soluble film may be colored.

Further, in the above invention, the water-soluble film is polyvinyl alcohol, dextrin, gelatin, glue, casein, shellac, gum arabic, starch, polyacrylic acid amide, sodium polyacrylate, polyvinyl methyl ether, polyvinyl pyrrolidone, Cellulose, acetyl cellulose, acetyl butyl cellulose, carboxymethyl cellulose, methyl cellulose,
Alternatively, it may be composed of hydroxyethyl cellulose.

In the above invention, the water-soluble film may have a thickness of 10 to 250 μm.

Further, in the above invention, when the water-soluble film is immersed in water having a water temperature of 20 ° C. for 3 minutes, the remaining area of the window of the water-soluble film is 60% or less of the original area. Good.

In the above invention, the water-soluble film may be held between two sheet-like supports having windows at the same position.

In the above invention, the water-soluble film may be held between the sheet-like supports having two windows and being folded in two and having the windows aligned with each other.

Further, the portable transmitter / receiver device of the present invention is configured such that the water wetting detection sheet according to any one of claims 1 to 7 is housed inside.

[0016]

Embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the water wetting detection sheet of the present invention. FIG. 2 is a perspective view showing another embodiment of the water wetting detection sheet of the present invention, and FIGS. 3 to 4 are plan views showing other embodiments of the water wetting detection sheet of the present invention. In the figure, 1 is a sheet-like support, 2 is a window, and 3 is a water-soluble film.

The water-wetting detecting sheet of the present invention is one in which a water-soluble film 3 is provided on a window portion 2 of a sheet-like support 1 in which a part made of a water-resistant material is removed like a window (see FIG. 1 to 4).

The sheet-shaped support 1 is made of a water-resistant material, and a part of the support 1 is removed like a window. As a material suitable for the sheet-shaped support 1, it is preferable to select a plastic sheet such as polypropylene or ABS, paper, or a composite material thereof, which is excellent in water resistance. The thickness of the sheet-shaped support 1 is preferably about 0.1 to 3 mm. The shape of the window portion 2 can be freely provided such as a circular shape or a square shape (see FIGS. 1 and 3). Further, the window portion 2 may have an open shape connected to the peripheral portion of the sheet-shaped support 1 (see FIG. 4). Further, an injection molded body may be used as long as it has a sheet shape.

As the water-soluble film 3, polyvinyl alcohol, dextrin, gelatin, glue, casein, shellac, gum arabic, starch, polyacrylic acid amide, sodium polyacrylate, polyvinyl methyl ether, polyvinyl pyrrolidone, cellulose, acetyl cellulose, It is preferable to use materials such as acetylbutyl cellulose, carboxymethyl cellulose, methyl cellulose, and hydroxyethyl cellulose, or a composite material containing these as the main components. The water-soluble film 3 has a thickness of 10 to 250 μ.
m, preferably 20-60 μm. Thickness is 10 μm
If it is smaller, it may be affected by humidity, and it is difficult to bond it to the window portion 2, mechanical strength is weak, and it is easily broken by a force such as pulling. In addition, if the thickness is greater than 250 μm, the penetration of water is slow even if it gets wet,
There is an inconvenience that it is difficult to judge that the film is not broken due to swelling / dissolution and it is difficult to judge.

When the water-soluble film 3 is immersed in water having a water temperature of 20 ° C. for 3 minutes, the remaining area of the water-soluble film 3 in the window 2 becomes
It is preferable to use the water-soluble film 3 whose area is 60% or less of the original area in order to determine whether the water-soluble film 3 is swollen / dissolved.

When the material of the water-soluble film 3 is transparent or opaque, the water-soluble film 3 may be colored so that breakage due to dissolution of the water-soluble film 3 can be easily detected. For that purpose, a water-soluble film 3 produced by mixing and dispersing a dye and a pigment in a film material may be used. It is also possible to provide a colored layer on one or both sides of the water-soluble film 3 for coloring. The colored layer may be printed on the water-soluble film 3 with a colored ink composed of a resin, a colorant and a solvent. As the resin of the coloring ink, it is preferable to use the same water-soluble resin as the film material. Also, a resin that is dissolved in an organic solvent can be used. For example, a resin binder or ink vehicle such as a cellulose resin such as ethyl cellulose, polyvinyl alcohol, rosin resin, shellac resin, OP varnish (normally used natural varnish or synthetic varnish for overprint) can be used,
As the natural linseed oil-based varnish or synthetic varnish, rosin, shellac, methyl cellulose, ethyl cellulose, nitrocellulose-based synthetic varnish for overprinting, or the like can be used.

In order to fix the water-soluble film 3 to the sheet-shaped support 1, the water-soluble film 3 is attached to the support without any slack. The water-soluble film 3 may be fixed so as to cover the entire window portion 2 (see FIGS. 1 and 2) or may partially cover the window portion 2 (see FIGS. 3 and 4). Water-soluble film 3
As a method for fixing the sheet to the sheet-shaped support 1, a method for fixing with an adhesive, a method for fixing with an adhesive or a double-sided tape, 2
There is a method of sandwiching the sheet-shaped support 1 between them.

As a method of fixing with an adhesive, an adhesive is applied to the periphery of the window 2 of the sheet-like support 1 having the hole-shaped window 2, and the water-soluble film 3 larger than the area of the window 2 is applied.
May be covered so as to cover the entire window portion 2 so that the water-soluble film 3 is adhered to the support by an adhesive.
The adhesive is composed of a solvent and a binder such as a resin and firmly adheres when the solvent dries, and a cyanoacrylate adhesive or a vinyl chloride adhesive is preferably used. As the adhesive, it is preferable to use one having water resistance. The reason is that the adhesive itself is attacked by water, the water-soluble film 3 falls off, and the reliability of the determination as to whether the water-soluble film 3 is dissolved is lost. Further, instead of the adhesive, an adhesive or a double-sided tape may be used for fixing.

As a method of sandwiching between two sheet-like supports 1, two sheet-like supports 1 each having a hole-like window portion 2 at the same position are used, and one sheet-like support 1 is provided with a water-soluble film 3 After fixing the water-soluble film 3 between the two sheet-shaped supports 1 so that the water-soluble film 3 is sandwiched by the other sheet-shaped support 1.
May be attached. Also, one sheet-shaped support 1
It is also possible to provide two window portions 2 at the same time, bend the two window portions 2 so as to overlap each other, and bond the water soluble film 3 so as to be sandwiched therebetween (see FIG. 2).

The water wetting detection sheet thus constructed is
It can be stored and used inside a portable transmitter / receiver device. To store the water wetting detection sheet inside the portable transmission / reception device, attach the water wetting detection sheet to the inside of the device, or sandwich the water wetting detection sheet in the mounting part that is pre-formed inside the device. Good.

The water-wetting detection sheet has only the water-soluble film 3 in the window portion 2 and is not lined with the sheet-like support 1. Therefore, the water-wetting detection sheet is eroded and dissolved in water from both front and back surfaces of the water-soluble film 3. As the water-soluble film 3 is dissolved, the water-soluble film 3 is deformed or holes are opened, so that it is possible to determine whether or not the water has been wet.

[0028]

Example A sheet-like support was prepared by folding a polystyrene sheet having a thickness of 0.7 mm into two and hollowing out a circular window portion having a diameter of 15 mm so as to be line-symmetric with respect to the folding line. A cyanoacrylate adhesive is applied to the periphery of one of the two folded inner sides of the sheet-shaped support, and a water-soluble film made of polyvinyl alcohol having a thickness of 20 μm is adhered so as to cover the entire window. Then, a cyanoacrylate adhesive was applied to the periphery of the other window on the inside of the sheet-shaped support, which was folded in two, and the sheets were bonded together to obtain a water wetting detection sheet.

This water wetting detection sheet was fixed near the microphone part inside the mobile phone, immersed in water at a water temperature of 20 ° C. for 2 seconds and then pulled up, the mobile phone was disassembled and the water wetting detection sheet was confirmed. A part of the film was dissolved, and the residual ratio of the window portion was 10%.

A cell phone equipped with the water wetting detection sheet was left in a constant temperature and humidity chamber at a temperature of 40 ° C. and a humidity of 80% for 24 hours, but no change was observed in the water wetting detection sheet.

[0031]

Since the present invention has the above-described structure, it has the following effects.

Since the water-soluble film of the water-wetting detection sheet is soaked in water from both sides, the water-soluble film is easily melted, and it is easy to determine whether or not the water-wetting has occurred. In addition, it is easy to determine whether or not water has been wetted because the color is not changed and the hole is opened. In addition, since it does not reversibly return to its original state even when it is dried, it is possible to reliably determine whether or not it has been wet with water.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a water wetting detection sheet of the present invention.

FIG. 2 is a perspective view showing another embodiment of the water wetting detection sheet of the present invention.

FIG. 3 is a plan view showing another embodiment of the water wetting detection sheet of the present invention.

FIG. 4 is a plan view showing another embodiment of the water wetting detection sheet of the present invention.

[Explanation of symbols]

 1 sheet-like support 2 window 3 water-soluble film

Claims (8)

[Claims] 1. A water-wetting detection sheet, characterized in that a water-soluble film is provided on a window portion of a sheet-shaped support, which is made of a material having water resistance and has a window-shaped portion. 2. The water wetting detection sheet according to claim 1, wherein the water-soluble film is colored. 3. A water-soluble film comprising polyvinyl alcohol, dextrin, gelatin, glue, casein, shellac, gum arabic, starch, polyacrylic acid amide, sodium polyacrylate, polyvinyl methyl ether, polyvinyl pyrrolidone, cellulose, acetyl cellulose,
The water wetting detection sheet according to any one of claims 1 to 2, which is composed of acetyl butyl cellulose, carboxymethyl cellulose, methyl cellulose, or hydroxyethyl cellulose. 4. The water wetting detection sheet according to claim 1, wherein the water-soluble film has a thickness of 10 to 250 μm. 5. The water-soluble film is used in water having a water temperature of 20 ° C.
The water wetting detection sheet according to any one of claims 1 to 4, wherein the remaining area of the window portion of the water-soluble film is 60% or less of the original when soaked for a minute. 6. The water wetting detection sheet according to claim 1, wherein a water-soluble film is held between two sheet-shaped supports having windows at the same position. 7. The water-wetting detection sheet according to claim 1, wherein the water-soluble film is held between sheet-like supports having two windows and folded in two so that the windows coincide with each other. 8. A portable transmitter / receiver device comprising the water wetting detection sheet according to claim 1 housed therein.