JP2015200773A - indicator label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indicator label requiring no base material with a hiding layer for resolving a problem of a period lapse display indicator label, including a period lapse display indicator function only using a base material with a single dye diffusion layer, allowing easy manufacture by printing, capable of preventing interpolation, and reusable.SOLUTION: An indicator label includes: a dye diffusion layer containing a dye and a binder polymeric resin on a base material; and an adhesive material layer on the opposite side of base material. Time lapse can be displayed as a color fades through aggregation of the dye in the dye diffusion layer with the time lapse.

Description

  The present invention relates to an indicator label that indicates elapsed time and history by using a change in color depending on a period and temperature.

  Indicator labels have been developed and used in various fields for various purposes. Some are known to be able to indicate the pH range by color change due to acid or alkali, as seen in acid-base indicators, and indicator labels using this have been put to practical use. In addition, some are devised so that the state of oxidation or reduction of a substance can be identified by the difference between the reductant color and the oxidant color as seen in the redox indicator.

  In addition, those that detect specific substances by utilizing the color change in response to specific substances or those that change color in response to light of a specific wavelength such as ultraviolet rays have been developed. There are known indicator labels that use cobalt discoloration, indicator labels that detect ultraviolet rays using a photochromic substance that reversibly reacts with ultraviolet rays and develops color.

  On the other hand, a period elapsed display indicator or a period elapsed display indicator label capable of displaying a usage time by utilizing a color change with time has also been put into practical use. In particular, those that use color changes over time can inform the time of replacement of fragrances, insect repellents, etc., and check the validity period of tickets such as admission tickets, membership cards, and various certificates at a glance. It can be used widely for security purposes.

  Conventionally, there is a method in which a volatile chemical is used as such an indicator or indicator label so that the degree of diffusion of a solvent or a waxy drug can be visually observed from the outside of the container. However, in this system, since volatile components are diffused in the air, problems in terms of hygiene have been pointed out.

  There is also an indicator or indicator label that can know the elapsed time from the color change caused by oxygen and carbon dioxide contained in the air. However, this method has a problem that the color change is affected by the humidity in the air.

  In order to solve such a problem, a period elapsed display indicator label has been developed (Patent Document 1). However, in the system shown here, the history by temperature and time is displayed after the two substrates of the substrate provided with the concealing layer and the substrate provided with the dye diffusion layer are bonded together. Therefore, the configuration is complicated and handling is complicated. In addition to convenience, it has been demanded to improve environmental protection in addition to convenience because it is limited to one-time use and cannot be reused. Further, in the case of a period elapsed display indicator label, in many cases, a function of preventing falsification by replacing the label is also required.

Japanese Patent No. 3144187

The present invention eliminates the need for a base material provided with a concealing layer in order to solve the above-described problem of the time-lapse display indicator label, which has been regarded as a problem in the past, and requires only a base material provided with a single dye diffusion layer. It is an object of the present invention to provide an indicator label that has a progress indicator function, can be easily manufactured by printing, can be prevented from being tampered with, and can be reused.

  As a means for solving the above problems, the invention according to claim 1 has a dye diffusion layer containing a dye and a binder polymer resin on a base material, and an adhesive on the opposite surface of the base material. The indicator label is characterized in that it has a layer and can display the passage of time by the color becoming light by the aggregation of the dye in the dye diffusion layer over time.

  The invention according to claim 2 is the indicator label according to claim 1, wherein the dye is redispersed by heating to 70 ° C. or more after the dye has aggregated.

  The invention according to claim 3 is the indicator label according to claim 1 or 2, wherein the substrate is paper or plastic film.

  The invention according to claim 4 is the indicator label according to any one of claims 1 to 3, wherein the dye has a molecular weight of 400 g to 600 g / mol.

  The invention according to claim 5 is the indicator label according to any one of claims 1 to 4, wherein the binder polymer resin is a rubber-based resin.

  The invention according to claim 6 is characterized in that the ratio of the dye to the binder polymer resin is dye: binder polymer resin = 1: 10-20. This is the indicator label.

  According to the first aspect of the present invention, since the dye in the dye diffusion layer aggregates with the passage of time, the color tone exhibited when the initial dye was dispersed in the binder polymer resin becomes a light color with the passage of time. It has a period elapsed display indicator function. In contrast, the conventional indicator label exhibits a period display indicator function by shifting to another layer where the dye has a concealing property, whereas the indicator label according to the present invention utilizes the change in color of the dye diffusion layer itself. Therefore, another base material provided with a concealing layer is unnecessary.

  Furthermore, it can be easily manufactured by printing, and when an organic solvent is used to peel off the label for falsification, the dye diffusion layer elutes and discolors and is difficult to falsify. In addition, it is possible to provide an indicator label that can be reused because it is a reversible change in which the dye once aggregated is redispersed by heating.

  The indicator label is convenient because it has an adhesive layer on the opposite side through the base material of the dye diffusing layer and can be used in a necessary place, and there is little risk of loss.

  According to invention of Claim 2, the indicator label which can be reused easily by heating at 70 degreeC or more can be provided.

According to invention of Claim 3, the base material in which the concealing layer was provided is unnecessary, and the indicator label which can display progress of time only with the base material which provided the single dye diffusion layer is provided. Can do. Moreover, the indicator label which can be easily manufactured by printing and coating using paper or a film as a base material can be provided.

  According to invention of Claim 4, the indicator label which can display progress of a period more effectively and correctly only with the base material which provided the single dye diffusion layer can be provided.

  According to the fifth aspect of the present invention, it is possible to display the time period more effectively with only the base material provided with a single dye diffusion layer. In addition, after the indicator label is used, the once aggregated dye can be redispersed by heating, so that an indicator label that can be reused can be provided.

  According to the sixth aspect of the present invention, the indicator label can change the color density of the dye diffusion layer so that the change in color density can be visually perceived more effectively and can display the passage of time more accurately. Can be provided.

FIG. 1 is a partial sectional schematic view showing an embodiment of an indicator label according to the present invention. FIG. 2 is a schematic overhead view showing an embodiment of the indicator label according to the present invention. FIG. 3 is a partial schematic cross-sectional view showing a state in which the indicator label is left standing and the dye is aggregated according to the present invention. FIG. 4 is a bird's-eye view schematic diagram showing a state in which the indicator label is left standing and the dye is agglomerated according to the present invention. FIG. 5 is a partial cross-sectional schematic diagram showing a state in which the indicator label is left standing time and the aggregation of the dye reaches a saturated state according to the present invention. FIG. 6 is a bird's-eye view schematic diagram showing a state in which the indicator label is left standing and the dye aggregation reaches a saturated state according to the present invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to FIGS.

  As shown in FIG. 1, the indicator label (10) has a dye diffusion layer (2) on a substrate (1), and has an adhesive layer (5) and a release paper (6) on the back surface. FIG. 1 is a partial cross-sectional schematic view showing an embodiment of an indicator label according to the present invention. In the initial state, the dye (3) has not yet passed and is dispersed in the binder polymer resin of the dye diffusion layer (2). ) Has a dark color. FIG. 2 is a schematic plan view of the indicator label at this time as seen from the dye diffusion layer (2) side, and the surface is uniformly dark. This is because the dye generally exhibits a dark color when sufficiently dispersed.

  In FIG. 3, the dye in the dye diffusion layer (2) begins to aggregate with time, and as a result, the color is lighter than the initial color as a whole. The dye forms aggregated dye (4). FIG. 4 is a schematic plan view of the indicator label at this time as seen from the dye diffusion layer (2) side. In the initial state, the dye is agglomerated and localized and the density is reduced compared to the dye dispersed in the dye diffusion phase (2) and exhibiting a dark color.

In FIG. 5, the dye agglomeration is almost saturated as time elapses, and the color is lighter as a whole. This is the end of the color change.
FIG. 6 is a schematic plan view of the indicator label at this time as seen from the dye diffusion layer (2) side. It shows that the aggregation of the dye is further advanced and the concentration is further reduced.

  The indicator label in the state shown in FIG. 5 and FIG. 6 returns to a state like the dye (3) in which the dye (4) aggregated by heating is dispersed again and dispersed in the binder polymer resin, The color density is also restored.

Paper or plastic film can be used for the substrate (1). The plastic film can be used as long as it is a commonly used film and can be printed or coated. For example, cellophane, vinyl chloride, polyethylene, polypropylene, polyethylene terephthalate, polyimide, polycarbonate, polystyrene, or the like can be used.
The same applies to paper and can be used if printing or coating is possible.

  The dye diffusion layer (2) can be formed on the substrate (1) by printing or coating. As a printing method, gravure printing, flexographic printing, offset printing, silk screen printing, or the like can be used, and it can also be formed using various coating machines.

  When printing is used, it is also possible to provide the dye diffusion layer (2) in a pattern in addition to full-surface printing. Further, when surface protection is required, a protective layer made of a transparent film or overcoat may be provided on the dye diffusion layer (2).

  The dye is applied in a state of being dissolved and dispersed in the binder polymer resin. In order to impart printing and coating suitability, an organic solvent is appropriately added to adjust the viscosity and flow characteristics. If the binder polymer resin is a rubber-based resin, it is more preferable that the dye is more easily dispersed and aggregated.

  Examples of rubber resins that can be used here include isoprene (IR), butadiene (BR), styrene-butadiene (SBR), nitrile (NBR), chloroprene (CR), butyl (IIR), ethylene propylene (EDPM), and chlorosulfone. Polyethylene (CSM), chlorinated polyethylene (CM), acrylic (ACM), silicon (Q), fluorine (Viton et al.), Thiocol (T), urethane (U), epichlorohydrin (CO, ECO), and the like.

  The dye that can be used here can be selected from oil-soluble dyes and disperse dyes. For example, azo dyes such as Solvent Yellow 2, Solvent Orange 1, Solvent Red 24, Solvent Brown 3, Solvent Yellow 10, Solvent Orange 5, Solvent Brown 37, Solvent Red 8, and other azo metal complex salts, Solvent Violet 13, Solvent Blue 11 Anthraquinone dyes such as Solvent Green 3, Phthalocyanine dyes such as Solvent Blue 25, Disperse Orange 3, Disperse Red 1, Disperse Yellow 3, Disperse Violet 24, Disperse Blue 44 and other aminoazo dyes, Disperse Orange 11 Aminoanthraquinone dyes such as Disperse Red 4, Disperse Violet 1 and Disperse Blue 4, Utroarylamine dyes, and the like.

  It is more desirable that the dye has a molecular weight of 400 g to 600 g / mol from the viewpoint of facilitating aggregation and redispersion of the dye and making it easy to see changes in color shade.

The ratio of the dye to the binder polymer resin is more preferably dye: binder polymer resin = 1: 10 to 20 because the change in color shade due to the diffusion and aggregation of the dye appears more visually.

  Even if the dye aggregates over time after it has been used, and the aggregation becomes saturated and the color fades, it can be restored to the initial dark color by dispersing the dye again by heating. Can be reused. The temperature at this time is preferably 70 ° C. or higher, and the heating method may be any heating method other than general oven heating.

  In addition to being able to be reused by heating, heating at 70 ° C. or higher immediately before using the indicator label enables more accurate because the dye can start from a sufficiently dispersed state even for the first use. The elapsed time can be displayed.

  In the situation where an indicator label is used, when the label is peeled off and replaced with an organic solvent for the purpose of falsification, etc., the dye diffusion layer (2) comes into contact with the organic solvent when the dye diffusion layer (2) comes into contact with the organic solvent. Since (2) is eluted and the color of the dye disappears, tampering can be prevented.

  The adhesive layer (5) is used when the indicator label (10) is attached to a necessary place and used, and the release paper (6) is peeled off. A release film can be used as the release paper (6). The pressure-sensitive adhesive layer (5) may be a general pressure-sensitive adhesive, or a pressure-sensitive adhesive, a heat-sensitive adhesive, or the like depending on the application or request.

  Hereinafter, the indicator label according to the present invention will be described in more detail based on examples, but the present invention is not limited to the following examples.

  Paper is used for the base material, and the brand is NBR 6B manufactured by Tokai Paper Co., Ltd.

  MACROLEX E2R manufactured by LANXESS Inc. was used as the dye.

  Nipol 1723 (styrene butadiene rubber: SBR) manufactured by Nippon Zeon Co., Ltd. was used as the binder polymer resin.

  The dye was mixed with the binder polymer resin together with the solvent at a ratio of 1:15 to disperse the dye, and a dye diffusion layer having a thickness of 5 μm was formed using a silk screen printing method.

  The pressure-sensitive adhesive formed a pressure-sensitive adhesive layer using an acrylic adhesive P-512 manufactured by Nichiei Kako Co., Ltd.

L11 manufactured by Lintec Corporation was used as the release paper.
An indicator label was prepared with the above material composition.

(Evaluation 1)
The indicator label was allowed to stand in a two-level temperature environment of room temperature and 40 ° C. for 18 days, and the change in reflection density was measured using a Macbeth densitometer over time. Table 1 shows the measurement results.

As is apparent from Table 1, in any temperature environment of normal temperature and 40 ° C., the reflection density decreases with the passage of time from the initial reflection density of 1.0. At room temperature, it decreased to 0.2 on the 16th day at 40 ° C. and on the 12th day at 40 ° C., and it seems that the aggregation of the dye became saturated.

(Evaluation 2)
Furthermore, after heating once at 70 ° C. for 18 days to redisperse the dye and confirming that the reflection density returned to the initial value, the reflection density up to the 36th day was the same as in Evaluation 1. The change of was measured. Table 2 shows the measurement results.

From the results in Table 2, it can be seen that the reflection density returned to the initial value of 1.0 by heating at 70 ° C. for one hour, and the reflection density increased due to redispersion of the dye.
As a result of further leaving the indicator label after heating, the reflection density decreased with the passage of time from the initial reflection density of 1.0 in any temperature environment of normal temperature and 40 ° C. The result was reproduced on the numerical value.

  From these results, it has been confirmed that the indicator label according to the present invention has a function of displaying the passage of time due to a decrease in reflection density with the passage of time at room temperature and a temperature environment of 40 ° C. In addition, it was verified that heating to 70 ° C. for one hour returned to the initial dye dispersion state, and reuse became possible.

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Dye diffusion layer 3 ... Dye 4 of the state disperse | distributed in binder polymer resin ... Aggregated dye 5 ... Adhesive layer 6 ... Release paper 10 ... Indicator label

Claims (6)

On the substrate, has a dye diffusion layer containing a dye and a binder polymer resin,
Having an adhesive layer on the opposite side of the substrate,
An indicator label, characterized in that the passage of time can be displayed by the color fading due to the aggregation of the dye in the dye diffusion layer over time.   The indicator label according to claim 1, wherein the dye label is redispersed by heating to 70 ° C or higher after aggregation.   The indicator label according to claim 1 or 2, wherein the substrate is paper or a plastic film.   The indicator label according to claim 1, wherein the dye has a molecular weight of 400 g to 600 g / mol.   The indicator label according to any one of claims 1 to 4, wherein the binder polymer resin is a rubber-based resin.   The indicator label according to claim 1, wherein a ratio of the dye and the binder polymer resin is dye: binder polymer resin = 1: 10-20.