JP2001051600A - Water wetting detecting label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water wetting detecting label capable of easily discriminating the cause for the trouble occurring in the water wetting of mobile and portable precision electronic apparatus, etc. SOLUTION: This label has at least a base material 4 and a water wetting layer 5 disposed on this base material 4 and may be provided with a water permeable protective layer 9 and a display layer on the water wetting layer 5 on the base material 4 and may have a tacky adhesive layer 3 on the other side on the side having the water wetting layer 5 of the base material 4. The base material 4 is transparent, has the tacky adhesive layer 3 on the water wetting layer 5 on the base material 4 and may consist of the constitution subjected to a perforation treatment. The constitution respectively partially provided with the water wetting layer 5 and the tacky adhesive layer 3 having the thickness larger than the thickness of this layer on the base material 4 is equally preferable. The label has the protective layer 9 subjected to the perforation treatment on the water wetting layer 5 on the base material 4 and the water wetting layer 5 is printed with characters or images. Also, the constitution having the tacky adhesive layer 3 on another side of the base material is equally preferable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a portable telephone, a PH
S, portable electronic devices such as pagers, mobile radio, portable CD players, video cameras, etc.
Regarding the package for articles that react with water, such as calcium chloride and quicklime, and the sheet for detecting water wetting used for articles that do not get wet, such as dried fish, whether these have gone through submergence, wetness, etc. It relates to a water wetting detection label that can be detected.

[0002]

2. Description of the Related Art For example, mobile and portable precision electronic devices, such as mobile phones and portable CD players, are usually considered to have a certain degree of water resistance, but are exposed to rain or fall into a puddle. In some cases, the internal circuits and the like get wet with water and the function as an electric product is impaired. In such a case, it is difficult to determine whether the cause of the failure is due to water wetting or the range of normal use, and it is difficult to determine whether the cause is the carelessness of the user, that is, the general consumer. In some cases. So, in order to prevent such troubles,
On a base sheet, a label with a water-soluble coloring layer formed by applying a water-soluble coloring resin in which a coloring agent such as a dye or pigment is mixed or dissolved or dispersed in a water-soluble resin, and an adhesive layer such as an adhesive Is attached to the inside of the product in advance, and when a failure occurs, the state of the label is checked, and the cause of the failure is determined based on whether the water-based ink is bleeding or discolored. And so on.

[0003]

However, in the above-described method, it is possible to determine whether the label is wet while the label is wet, but the label returns to its original state when the label dries, and the label cannot be determined. It could not serve its purpose. An object of the present invention is to provide a water-wetting detection label that does not have the above-described disadvantages and that can easily determine the cause of a failure caused by water-wetting of a mobile, portable precision electronic device or the like. Is what you do.

[0004]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve the object of the present invention, and as a result, have provided a layer made of a water-swellable resin on a label to be attached to the electronic device. It has been found that the object of the present invention can be achieved by detecting water wetting by utilizing the swelling property. The present invention has been completed based on such findings.

That is, the present invention provides (1) at least:
A substrate, and a water wetting detection label having a water swelling layer on the substrate, (2) the water wetting detection label according to the above (1), which has a water permeable protective layer on the water swelling layer on the substrate, 3) The water wetting detection label according to the above (1) or (2), which has a display layer on at least the water swelling layer, and (4) a pressure-sensitive adhesive layer on the other side of the substrate having the water swelling layer. (1) to above
(3) The water wetting detection label according to any of (3), (5) wherein the base material is transparent, the pressure-sensitive adhesive layer is provided on the water swelling layer on the base material, and the porous substrate is subjected to a porous treatment. (1) the water wetting detection label according to (1), (6) the water wetting detection label according to (1), wherein the water swelling layer and the pressure-sensitive adhesive layer having a thickness larger than that of the layer are partially provided on the substrate, And (7) a protective layer which has been subjected to a porous treatment on the water-swelling layer on the substrate, wherein the water-swelling layer is printed as characters or images, and is provided on the other side of the substrate. It is intended to provide the water wetting detection label according to the above (1), which has an adhesive layer.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a label for detecting water wetting having at least a substrate and a water swelling layer provided on the substrate. The water-swellable layer in the present invention contains a water-swellable resin. As the water-swellable resin, any resin can be used as long as it can swell when it comes into contact with water, but a water-swellable synthetic high molecular compound is preferably used. Is preferably 5 to 30 times. Examples of such a water-swellable resin include (meth) acrylic acid, (anhydride) maleic acid, fumaric acid, crotonic acid, itaconic acid, 2- (meth) acryloylethanesulfonic acid, and 2- (meth) acryloylpropanesulfonic acid. , 2- (meth) acrylamido-2-methylpropanesulfonic acid, vinylsulfonic acid, styrenesulfonic acid and other anionic monomers and salts thereof; (meth) acrylamide, N-substituted (meth) acrylamide, 2-hydroxyethyl (meth) ) Acrylate, 2-hydroxypropyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, polyethylene glycolide (meth) acrylate, N-vinylpyrrolidone, N-
Nonionic hydrophilic group-containing monomer such as vinylacetamide; amino such as N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide Group-containing unsaturated monomers and their 4
Grade; polymer of hydrophilic monomer such as sulfonic acid group-containing unsaturated monomer represented by styrene sulfonate; said hydrophilic monomer and methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, etc. Copolymers of hydrophobic monomers with acrylates, vinyl acetate, styrene, acrylonitrile, vinyl propionate, etc .; grafted the hydrophilic monomers onto polymers such as styrene resin, polyester resin, acrylic resin, urethane resin Resins, etc .; water-absorbing alkyd resins, polyester resins, polyurethane resins, etc., using ethylene glycol or polyhydric alcohol as a monomer; other starch-acrylonitrile-graft copolymer crosslinked products;
A crosslinked product of acrylic acid-vinyl alcohol copolymer, a crosslinked product of maleic anhydride-polyvinyl alcohol copolymer, a saponified vinyl acetate-methyl acrylate copolymer, a modified crosslinked polyethylene oxide, and the like.

[0007] Such a water-swellable resin can be dissolved or dispersed in an organic solvent such as methyl ethyl ketone, toluene, cyclohexane or methanol and applied or printed on a substrate. In the present invention, various binders can be further added to the water-swellable layer in order to improve the fixability of the water-swellable resin to the substrate. As such a binder, a urethane resin, an acrylic resin, a polyester resin, a styrene-butadiene resin, a vinyl acetate resin, or the like can be used. In addition, a filler such as silica or calcium carbonate may be contained in order to promote the intrusion of water and adsorb and retain the intruded water.

The thickness of the water-swelled layer in the present invention is not particularly limited, but is preferably 0.05 to 200 μm. As the base material, for example, high-quality paper, paper such as impregnated paper, synthetic paper made of polyethylene resin or polypropylene resin, polyethylene, polypropylene, polyolefin such as ethylene-vinyl acetate copolymer, polyethylene terephthalate, polybutylene terephthalate, etc. Polyester,
Polyvinyl chloride, polyvinyl alcohol, polycarbonate, polyamide, polyimide, fluororesin, or a copolymer containing any of these, a polymer blend,
Examples include various synthetic resin films such as polymer alloys, and a laminate thereof may be used. The thickness of the substrate in the present invention is not particularly limited, but a thickness of 16 to 200 μm is used.

In the label for detecting water wetting of the present invention, it is preferable to provide an adhesive layer and a release sheet on the other side of the water swelling layer on the substrate. The pressure-sensitive adhesive used for the pressure-sensitive adhesive layer includes, for example, a natural rubber-based pressure-sensitive adhesive, a synthetic rubber-based pressure-sensitive adhesive, an acrylic resin-based pressure-sensitive adhesive, a polyvinyl ether resin-based pressure-sensitive adhesive, a urethane resin-based pressure-sensitive adhesive, a silicone resin-based pressure-sensitive adhesive, and the like. Is mentioned. Specific examples of the synthetic rubber-based adhesive include styrene-
Butadiene rubber, polyisobutylene rubber, isobutylene-isoprene rubber, isoprene rubber, styrene-isoprene block copolymer, styrene-butadiene block copolymer, styrene-ethylene-butylene block copolymer, ethylene-vinyl acetate thermoplastic elastomer, etc. No. Specific examples of the acrylic resin-based pressure-sensitive adhesive include a single polymer such as acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate, ethyl methacrylate, and acrylonitrile. A coalescence or a copolymer is mentioned. Specific examples of the polyvinyl ether resin-based pressure-sensitive adhesive include polyvinyl ether and polyvinyl isobutyl ether. Specific examples of the silicone resin-based pressure-sensitive adhesive include dimethylpolysiloxane. These adhesives can be used alone or in combination of two or more.
The surface of the pressure-sensitive adhesive layer may be covered with a release sheet to protect the surface of the pressure-sensitive adhesive layer and prevent dirt on the surface. The thickness of the pressure-sensitive adhesive layer in the present invention is not particularly limited,
70 μm is preferred.

As the release sheet, any of those known in the art may be used. For example, films made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene and polyarylate, and polyethylene laminated paper The base material is made of various paper materials such as polypropylene laminated paper, clay coated paper, resin coated paper, glassine paper, etc., and the surface to be bonded to the pressure-sensitive adhesive layer of the base material is subjected to release treatment as necessary. be able to. In this case, typical examples of the release treatment include application and formation of a release agent layer made of a release agent such as a silicone resin, a long-chain alkyl resin, or a fluorine resin. The thickness of the release sheet is not particularly limited, and may be appropriately selected.

The detection label of the present invention includes, as one embodiment, a label having a water-permeable protective layer on a water-swelling layer. The water-permeable protective layer is formed by providing a pressure-sensitive adhesive layer on a transparent resin film as a protective substrate, among the films listed as the base material, and further forming a hole in the protective substrate and the pressure-sensitive adhesive layer. One that has been processed (see FIG. 1).
The thickness of each of the protective base material layer and the pressure-sensitive adhesive layer is 5 to 30 μm.
, And 10 to 50 μm. The porosity treatment is performed, for example, by forming a hole having a diameter of
It can be performed by appropriately providing a density of 1 million / m ² . Further, the pressure-sensitive adhesive of the pressure-sensitive adhesive layer may be partially or linearly applied in a dotted or linear manner without or in combination with the porous treatment. This allows water to enter from the side surface of the pressure-sensitive adhesive layer.

Further, as the water-permeable protective layer, a material using a water-permeable or water-soluble resin such as, for example, polyvinyl alcohol, polyacrylamide, or starch, instead of the above-mentioned porous treated product, may also be used. Further, as the water-permeable protective layer, a material provided by applying a water-resistant varnish or resin by a printing method or the like so as to form a discontinuous pattern or a large number of holes can also be used. These water-permeable protective layers can be used as a single layer, and preferably have a thickness of 0.5 to 20 μm,
In this case, it is possible to apply simultaneously with the water swelling layer on the substrate. Examples of the coating method used in the present invention include a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, and the like, and the printing method includes letterpress printing, letterpress printing such as flexographic printing, and the like. Examples include lithographic printing including offset printing, intaglio printing including gravure printing, and stencil printing including screen printing.

Hereinafter, the water wetting detection label of the present invention will be specifically described with reference to the drawings. FIG. 1 is a sectional view showing an example of the detection label A of the present invention. The detection label 1 has a water swelling layer 5 on a base material 4 and an adhesive layer 3 and a release sheet 2 sequentially provided on the other side of the base material 4. Here, as the base material 4, there is no particular limitation, and the above-mentioned paper, synthetic paper, and various synthetic resin films are used. In the case where the base material 4 is used by attaching it to a display portion such as a character or a pattern, a transparent film is used. The water swelling layer is provided partially on the substrate, and preferably has a thickness of 1 to 50 μm. As the resin constituting the water swelling layer, those described above can be used. Pressure-sensitive adhesive and release sheet 2 used for pressure-sensitive adhesive layer 3
The above can also be used.

When the detection label of this embodiment is wet with water, the water swelling layer 5 swells, and the water swelling layer 5 becomes opaque, deformed, or its surface becomes matte. Can be. Further, in the detection label of the present embodiment, the substrate,
When a transparent material is used for the water swelling layer and the pressure-sensitive adhesive layer, and this is affixed to a portion on which manufacturing information of electronic devices or the like, a precautionary statement, or the like is described, the water-swelling layer is applied via the detection label of the present invention before wetting. The information can be read, while, after water wetting, the water swelling layer 5 swells and makes it possible to detect water wetting by making at least a part of the written portion invisible. At this time, it is necessary that a printed portion of information necessary for discriminating a product, for example, a bar code, a lot number, and the like can be read even after getting wet. For this reason, it is preferable to perform patterning or the like so as not to provide a water swelling layer on the portion, or to apply a water-resistant varnish or the like.

In this embodiment, a display layer composed of characters or patterns may be provided on the surface of the water-swelling layer by printing or the like. In this case, the water swelling layer is preferably not a discontinuous layer as shown in FIG. 1 but a continuous uniform layer, and the substrate is preferably opaque. As printing inks, oil-based, including water-soluble,
UV curable and the like can be used. After wetting, it can be detected that the characters and patterns on the surface are deformed and wet. Also,
In this embodiment, by adding a coloring agent such as a dye or a pigment to the water swelling layer, disappearance of the water swelling layer due to water wetting, deformation of the water swelling layer such as deformation of the boundary of the resin becomes more apparent, By using a water-soluble coloring agent as the coloring agent, or by providing a layer of a water-soluble coloring ink between the substrate and the water-swelling layer, these dissolve during water wetting, making water wetting more effective. Can be clearly detected. In addition, in the detection label A, it is preferable to provide a water-permeable protective layer 6 on the water-swellable resin layer 5 for abrasion resistance and prevention of wetting of the surface. As the water-permeable protective layer 6, a transparent film provided with an adhesive layer may be used. In this embodiment, a water-permeable protective layer in which a pressure-sensitive adhesive layer 10 is partially provided on a transparent film (protective substrate) 9 and a hole 11 is provided by a porosity treatment is used. In the detection label A of this embodiment, an example in which the pressure-sensitive adhesive layer 3 and the release sheet 2 are provided is shown. However, these may not be provided in the case of a tag with a string or being attached by means such as fitting into an article.

FIG. 2 is a sectional view showing an example of the detection label B of the present invention. The detection label 1 has a water swelling layer 5 on a substrate 4.
And an adhesive layer 3 and a release sheet 2 are sequentially provided thereon. The base material, the pressure-sensitive adhesive layer, and the release sheet can be made of the same materials as those used for the detection label A. The member including the base material 4, the water-swellable resin layer 5, and the pressure-sensitive adhesive layer 3 is subjected to a porous treatment after the application. The porosity treatment is, for example,
It can be performed by appropriately providing holes having a diameter of 0.5 to 5 mm at a density of 500 to 1,000,000 holes / m ² . In the detection label B, when the water is wet, water enters the inside of the layer through the large number of holes provided above, penetrates through the side surface of the water swelling layer 5 in the holes, and swells the resin. Can be achieved. The thickness of the water swelling layer 5 is 5
It is preferably from 100 to 100 μm. In addition, in this embodiment, by adding a water-soluble coloring agent to the water-swelling layer 5, they can be configured to be dissolved in water at the time of water wetting, so that water wetting can be more clearly detected. . Also,
As described above, it is also possible to adopt a method of not performing the above-described porosity processing on the printed portion of the information necessary for discriminating the product.

FIG. 3 is a sectional view showing an example of the detection label C of the present invention. The detection sheet 1 has a water swelling layer 5 on a substrate 4.
And a pressure-sensitive adhesive layer 3 having a thickness larger than that of the layer, and a release sheet 2 is further provided thereon. The base material, the pressure-sensitive adhesive layer, and the release sheet can be made of the same materials as those used for the detection label A. In addition, both the water swelling layer 5 and the pressure-sensitive adhesive layer 3 are partially
Preferably, the coating is alternately applied or printed as shown in FIG. 3, but the thickness of the water-swellable layer is preferably 1 to 35 μm, and the interval is preferably 0.05 to 10 mm. The pressure-sensitive adhesive layer is preferably provided so as to have a thickness of 1.2 to 3 times the thickness of the water swelling layer. By doing so, when the release sheet 2 is peeled off and the present label is adhered to the product base, water invades from the gap between the water swelling layer 5 and the product base upon water wetting, and the water swells. Swell the layer,
The object of the present invention can be achieved. The water swelling layer 5
And a method of forming the pressure-sensitive adhesive layer 3 on the base material 4, a method of forming a water-swellable layer first by a printing machine such as a screen, a method of forming a pressure-sensitive adhesive layer later, or a water-swellable layer and a pressure-sensitive adhesive layer by a die coater sequentially or A method of forming them at the same time is mentioned. In this embodiment,
To more clearly detect water wetting, a water-soluble coloring agent is added to the water-swelling layer 5 or a water-soluble coloring transparent ink layer is printed between the base material 4 and the water-swelling layer 5. ,
They can also be configured to dissolve in water when wet.

FIG. 4 is a sectional view showing an example of the detection label D of the present invention. The detection label 1 is provided with a water-swelling layer 5 in the form of letters or images on a substrate 4 via a coloring ink layer 8 as necessary, and a water-permeable protective layer of a water-resistant varnish having a porous layer thereon. 6 and the pressure-sensitive adhesive layer 3 and the release sheet 2 are sequentially provided on the other side of the base material 4. As the substrate, those similar to those used for the detection label A can be used, and an opaque substrate is particularly preferable. The coloring ink layer 8 is made of a water-soluble or oil-soluble ink such as a UV ink. Further, both the coloring ink layer 8 and the water swelling layer 5 can be provided by printing,
When both are provided, the respective thicknesses are preferably 0.05 to 5 μm and 0.05 to 20 μm, respectively.

According to this embodiment, the water-swellable layer 5 is made of a water-swellable resin mixed with a black pigment or dye, and is provided in the form of characters or images as product manufacturing information. . When the water is wetted, the water-swellable resin swells, so that a character or image printed using the water-swellable resin is destroyed, so that water wetting can be detected. As in the case of the detection label A, a printed portion of information necessary for discriminating a product, for example, a bar code, a lot number, and the like, can be read even after being wet with water. Inks and the like can also be used.

Although the coloring ink layer 8 is used as needed, it is preferably provided between the base material 4 and the water swelling layer 5 when it is provided. With this configuration, the water swelling layer 5 is formed by swelling due to the above-mentioned water wetting.
When the printed portion is destroyed, the color of the coloring ink appears, and the detection of water wetting can be performed more clearly. When printing the water swelling layer 5 and the coloring ink layer 8 on the substrate 4, it is preferable that the width of the coloring ink layer 8 is provided to be slightly smaller than the width of the water swelling layer 5 by trapping. Although a water-resistant varnish is used as the water-permeable protective layer 6 in this embodiment, a water-permeable protective layer made of a transparent film may be used as in the case of the label A. Further, the pressure-sensitive adhesive layer 3 and the release sheet 2 may not be used while being sandwiched between articles.

[0021]

EXAMPLES The present invention will be described more specifically below with reference to examples. Example 1 A resin obtained by grafting an acrylic acid monomer to a styrene resin as a water-swellable resin on a transparent polyethylene terephthalate film having a thickness of 16 μm as a substrate 4 (trade name: Dicewell SG-1002; (Manufactured by Nissei Chemical Industry Co., Ltd.) was printed with a screen printer at a diameter of 5 mm at intervals of 10 mm to provide a water-swelling layer 5 having a thickness of 50 μm.
Then, after drying on a release-treated surface of 70 g / m ² (about 70 μm thickness) glassine paper that has been release-treated with a silicone resin,
A release sheet 2 provided with a pressure-sensitive adhesive layer 3 coated and dried with an acrylic pressure-sensitive adhesive (trade name: PL Syn: manufactured by Lintec Co., Ltd.) so as to have a thickness of μm is prepared.
The surface on which the water swelling layer 5 is provided and the surface on the opposite side,
Detection label 1 was obtained. (FIG. 1) On the surface of the detection label 1 on which the water swelling layer 5 is provided, a 20 μm acrylic adhesive 10 (trade name: PAT) is applied to a 16 μm thick polyethylene terephthalate film as a protective substrate 9.
1: Lintec Co., Ltd.), and a protective film (water-permeable protective layer 6) having 40,000 holes / m ² having a hole of 2 mm in diameter was adhered to obtain a detection sheet having a protective layer.
(FIG. 1) The detection sheet having the protective layer was cut into a size of 30 mm × 40 mm, affixed on a notice of a mobile phone battery, immersed in water for 10 seconds, and pulled up. After the lifting, the pores and the surrounding water swelling layer swelled and became cloudy or water drops disappeared after 10 minutes of lifting, but the water swelling layer remained cloudy and it was difficult to read any precautionary statements and wet with water Was detected.

Example 2 As a base material 4, a resin obtained by grafting an acrylic acid monomer to a styrene resin as a water-swellable resin with a blade coater on one side of a high-quality paper of 64 g / m ² (about 80 μm) (trade name: Die Well SG-1002; water swelling 20 times,
(Daiichi Seika Kogyo Co., Ltd.) was applied and dried to form a water-swelling layer 5 having a thickness of 40 μm. Next, a release sheet 2 provided with an adhesive 3 was prepared in the same manner as in Example 1, and this was attached to the high-quality paper to obtain a detection label 1. Characters are printed on the surface of the water swelling layer 5 of the detection label by ordinary offset printing, and a varnish is printed thereon in a mesh (opening ratio: about 10%) to form a water-permeable protective layer 6 (2 μm in thickness). Thus, the detection label 1 with a protective layer was obtained. (Fig. 1) The obtained detection sheet with a protective layer was cut into a size of 10 mm x 20 mm, attached to a battery of a mobile phone, and placed in water.
It was immersed for 0 seconds and taken out. Before the immersion, the characters and the like on the detection sheet could be read, but immediately after the removal and after the removal and drying, it was possible to detect that the shape of the characters on the water swelling layer had collapsed and that the characters were wet with water.

Example 3 A transparent polyethylene terephthalate film having a thickness of 25 μm was used as a substrate 4 and 100 parts by weight (solid content) of the same water-swellable resin as used in Example 1 was mixed with silica (nip seal E1).
50: manufactured by Nippon Silica Co., Ltd.), and a mixed solution obtained by mixing 20 parts by weight was applied with a knife coater and dried to form a water-swelled layer 5 having a thickness of 40 μm. Next, a thickness of 3 which has been stripped with silicone resin.
A release sheet with an adhesive prepared by applying an acrylic pressure-sensitive adhesive 3 (trade name: PL Shin: manufactured by Lintec Co., Ltd.) (thickness: 20 μm) to an 8 μm polyethylene terephthalate film (release sheet 2) was prepared in advance, and the pressure-sensitive adhesive 3 and the The water swelling layer 5 was bonded. Further, 10,000 holes / m ² of holes 11 with a diameter of 2 mm were opened from the base material side, and a detection label 1 was obtained. (FIG. 2) The obtained detection label was cut into a size of 40 mm × 50 mm, affixed on a notice of a battery of a portable video camera, immersed in water for 10 seconds, and taken out. The precautionary statement was read before immersion, but after removal, the hole and its surroundings became cloudy, the letters on the precautionary statement were difficult to read, and it was possible to detect that it was wet with water.

Example 4 The same water-swellable resin as that used in Example 1 was printed on a polyethylene terephthalate film having a thickness of 25 μm as a substrate 4 with a screen printer at 2 mm width and 5 mm intervals. A water swelling layer 5 having a thickness of 20 μm was provided. next,
The adhesive 3 (trade name: PL Shin; manufactured by Lintec Corporation) was printed in a streak shape (thickness: 50 μm) between the streaks of the water-swellable resin with a screen printer, and the release sheet used in Example 1 was printed on the printing surface. 2 was adhered to obtain a detection label 1. (Fig. 3) When a water wetting test was performed using the obtained detection label in the same manner as in Example 1, the precautionary statement was read before immersion, but after intrusion, water entered from the end of the detection sheet. The water swelling layer became cloudy, making it difficult to read the precautionary statement, and it was possible to detect that the sheet was wet with water.

Example 5 As a substrate 4, a 25 μm-thick transparent polyethylene terephthalate film was coated with a blue UV ink (trade name: UV ACE FX: manufactured by Kuboi Ink Co., Ltd.) by a flexographic printing machine at 1 cm square and 20 mm intervals. Was printed, and a colored ink layer 8 having a thickness of about 0.8 μm was provided. Next, a coating liquid consisting of 20 parts by weight of carbon black (trade name: Dynamic SZ Color: manufactured by Dainichi Seika Kogyo Co., Ltd.) and 80 parts by weight of the water-swellable resin used in Example 1 was applied to a screen printer at 1.2 cm.
A square pattern with a square was printed so as to cover the ink layer, and a water-swelling layer 5 having a thickness of 20 μm was provided. Then, the varnish was printed so as to have 80,000 holes / m ² of 2 mm holes,
A water-permeable protective layer 6 having a thickness of about 2 μm was provided. Next, a release sheet with a pressure-sensitive adhesive was obtained in the same manner as in Example 1, and the pressure-sensitive adhesive layer 3 and the base material 4 were bonded to each other to obtain a detection label 1 of the present invention. This detection label was cut into a size of 20 mm x 40 mm, affixed on a notice of a battery for a mobile phone, immersed in water for 10 seconds and pulled up, and the water swelling layer softened, and the ink layer under the water swelling layer was softened. Blue ink was seen through, and it was detected that the ink was wet with water.

[0026]

As described in detail above, the water wetting detection label of the present invention has a layer made of a water-swellable resin, so that it can be used for portable and mobile precision electronic devices such as mobile phones, radios, and the like. It is possible to easily determine the cause of a failure caused by water wetting of an electric product or the like used outdoors such as a video camera.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a detection label A of the present invention.

FIG. 2 is a schematic sectional view showing an example of a detection label B of the present invention.

FIG. 3 is a schematic sectional view showing an example of the detection label C of the present invention.

FIG. 4 is a schematic sectional view showing an example of the detection label D of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Detection label 2 Release sheet 3 Adhesive layer 4 Substrate 5 Water swelling layer 6 Protective layer 8 Coloring ink layer 9 Protective substrate 10 Adhesive layer 11 Hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09F 3/10 G09F 3/10 A

Claims (7)

[Claims] 1. A water-wettable label having at least a substrate and a water-swelling layer on the substrate. 2. The label according to claim 1, further comprising a water-permeable protective layer on the water-swelling layer on the substrate. 3. The label according to claim 1, further comprising a display layer on at least the water swelling layer. 4. The label according to claim 1, further comprising an adhesive layer on the other side of the substrate having the water swelling layer. 5. The substrate according to claim 1, wherein the substrate is transparent, has a pressure-sensitive adhesive layer on the water-swelling layer on the substrate, and is subjected to a porous treatment.
Water wetting detection label described. 6. The water wetting detection label according to claim 1, wherein a water swelling layer and a pressure-sensitive adhesive layer having a thickness larger than the water swelling layer are partially provided on the base material. 7. A water-swelling layer on a substrate, comprising a porous protective layer, wherein the water-swelling layer is printed as characters or images, and the other side of the substrate. The water wetting detection label according to claim 1, further comprising an adhesive layer.