JPH0727878A - Time indicator - Google Patents

Abstract

PURPOSE:To realize an indicator attachable to products of wide usage by overlaying a layer including electron-donating coloring organic compounds with a specific distribution coefficient and a layer having electron acceptance. CONSTITUTION:When layer A and layer B made of a thermal plastic resin (for example; olefin resin) or an adhesive (for example; latex adhesive) are overlayed, layer A in colorless state containing electron-donating coloring organic compound with a distribution coefficient between the two layers of 0.1 or more and layer B in colorless state having electron acceptance are overlayed. As a result, the coloring of B layer B becomes stronger with time and thus an indicator capable of indicating the elapsed time after overlaying the two layers can be obtained. It is also, possible to lay a barrier not permeable to the electron donating coloring organic compound on the outer surfaces of the overlayed A layer A and layer B or to cover the both layers with the barrier layer. As for the electron-donating coloring organic compound, such compounds as rhodaminelactams and fluorans are usable.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a time indicator. More specifically, fungicides, fungicides, herbicides,
Visually determine the effective period of products with limited effective period such as plant growth regulators, pheromone preparations, juvenile hormone mimetics, insect repellents, repellents, deodorants, fragrances, pharmaceuticals, foods, etc. by changing the color tone Regarding the time indicator made possible.

[0002]

2. Description of the Related Art A composition comprising, as a time indicator, a color-developing organic compound component, a second component for developing the color, and a third component for decoloring the system when added to a system in which these two components are colored. Is mainly spread and held on a base material such as paper or non-woven fabric, and the second or third component of these three components remains one after being volatilized under the use environment and the color-developing organic compound component. A method in which decolorization or color development is observed due to the action of (for example, JP-A-62-235562, JP-A-63-60901, JP-A-2-290591).
(Japanese patent publication) is conventionally known.

However, in these methods, the volatilization rate of the above-mentioned second or third component greatly differs depending on the use environment, and when the volatilization surface comes into contact with clothes or the like, the rate of transfer to clothes or the like is higher than the volatilization rate. The problem is that the color change period is greatly influenced by the use environment and is not constant because the color changes due to the high speed. In addition, when clothes or the like come into contact with the volatilization surface, the color easily fades to cause discoloration or stains on the clothes, or when the product is spread and held on a substrate such as paper or nonwoven fabric, the discoloration period is generally. It has shortcomings such as being short and difficult to control the discoloration period. In addition, when used as a time indicator by attaching to various products with a valid period, it is applicable to applications such as pharmaceuticals and foods from the viewpoint of environmental pollution due to volatilization of the above-mentioned second or third component into the use environment. There is also a problem in that the usage scene is limited because it is difficult to do and cannot be used as a time indicator because the second or third component is hard to volatilize in a small space or a closed space.

[0004]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, distributed the components causing coloration and decolorization between the two superposed layers to form a layer. I found the time indicator of the present invention that changes color,
This solves problems such as environmental pollution due to volatilization of additive components into the use environment, discoloration of the indicator, and difficulty in controlling the discoloration period because the discoloration period is easily influenced by the use environment. The present invention has been completed by finding out that it can be used by being attached to a product having a wide range of uses.

[0005]

That is, according to the present invention, when a layer A and a layer B made of a thermoplastic resin or a pressure-sensitive adhesive are superposed, a distribution coefficient between the two layers [distribution coefficient = B at distribution equilibrium]. The concentration of the electron-donating color-developing organic compound in the layer) / (the concentration of the electron-donating color-changing organic compound in the layer A at the distribution equilibrium)] is 0.1 or more. By superposing the layer A, which contains and is in a decolored state, and the layer B, which has an electron accepting property and is in a decolorized state
The present invention provides a time indicator characterized in that the color of the B layer becomes darker with time, and that it is possible to show the passage of time after both layers are superposed.

The time indicator of the present invention is one in which the electron-donating color-forming organic compound is distributed from the A layer to the B layer and changes color in the process of reaching distribution equilibrium. The larger the distribution coefficient of the electron-donating color-developing organic compound between the A layer and the B layer at the operating temperature, the larger the thickness of the B layer relative to the A layer, and the more the electron donating property of the B layer at the distribution equilibrium. Since the concentration of the chromatic organic compound is high, the change in color tone is large. The partition coefficient of the electron-donating color-developing organic compound between the A layer and the B layer is preferably 0.1 or more. When the distribution coefficient is 0.1, the thickness of the B layer is 10 times or more that of the A layer, and when the distribution coefficient is 1, it is 1 time or more and the distribution coefficient is 10 times or more.
In the case of, it is preferable to make it 0.1 times or more. here,
The partition coefficient of the electron-accepting organic compound between the A layer and the B layer at the use temperature is determined by superimposing the A layer and the B layer at the use temperature, and determining the concentration of the electron accepting organic compound in the A layer and the B layer. Was measured over time, and A at the time when distribution equilibrium was reached
By knowing the concentration of the electron-accepting organic compound in the layer and the B layer, it can be calculated by the following formula. (Partition coefficient of electron-donating color-developing organic compound) = (concentration of electron-donating color-developing organic compound in layer B at distribution equilibrium) / (electron-donating color property in layer A at distribution equilibrium) Organic compound concentration)

In order to suppress the release of the electron-donating color-developing organic compound in the time indicator of the present invention to the environment due to transpiration, transfer, outflow, etc., to a smaller amount, the A layer and the B layer are superposed. A barrier layer through which an electron-donating color-developing organic compound cannot pass is laminated on one side of each of the A layer and the B layer, which are outer surfaces of the layer, or the layer A and the B layer are superposed on each other. May be encapsulated with a barrier layer that does not allow permeation. The barrier layer used varies depending on the type of the electron-donating color-forming organic compound, but various films such as polyester, Eval, nylon, polyvinylidene chloride, polypropylene, and transparent materials such as glass can be appropriately used. Further, an opaque material such as aluminum or an inorganic vapor deposition film may be used for a part of the barrier layer. These barrier layers and / or A
The layer and / or the B layer may be printed and colored in advance. For example, by changing the color tone by printing a letter such as "End of use" in the same color as the color of the electron-donating color-developing organic compound, or by coloring it differently from the color of the electron-donating color-developing organic compound. Can be more clear.
Furthermore, for example, for the reason of, for example, adding a weather-resistant agent for improving the weather resistance of the electron-donating color-developing organic compound, an additive or the like is added to the barrier layer within a range that does not impair the object of the present invention. You may.

In the present invention, the electron-donating color-developing organic compound is not particularly limited as long as it is a compound in which color development in an electron-accepting atmosphere reversibly occurs at a use temperature, and various conventionally known compounds can be used. For example, compounds such as rhodamine lactams, fluorans, triphenylmethane phthalides, phenothiazines, indolyl phthalides, spiropyrans, leuco auramines can be used. More specifically, rhodamine B base, N-phenylrhodamine lactam, crystal violet lactone, malachite green lactone, 1,3-dimethyl-6-diethylaminofluorane, 2- (2-chloroanilino) -6-dibutylamino. Fluoran, 3,7-bis (dimethylamino) -10-benzoylphenothiazine, N-3,3-trimethylindolinobenzospiropyran, ethyl leucomethylene blue and the like can be mentioned. These electron-donating color-forming organic compounds may be used alone or in combination of two or more.

Many of the electron-donating color-developing organic compounds used in the present invention are in a crystalline state when they exist alone at ordinary use temperature and pressure. These crystals have low color developability as they are, so when these are compounded in the A layer, they are melted by heating or dissolved in a solvent to disperse these compounds in the A layer in a molecular state (state not crystallized). It is preferable. When it is contained in the layer A in a crystalline state, the coloring property is low and the coloring is non-uniform, and it is necessary to blend a large amount of the electron-donating color-developing organic compound for uniform coloring. Absent.

The materials for the layers A and B in the present invention can be selected from various thermoplastic resins, adhesives and the like. The layer A is a layer which does not develop an electron-donating color developing organic compound, and the layer B is a layer which is electron-accepting and develops an electron-donating color developing organic compound. Distribution coefficient of 0.1
The above combinations can be selected. Whether or not the electron-donating color-developing organic compound used by various thermoplastic resins or pressure-sensitive adhesives is colored depends on the coloring state when the electron-donating color-developing organic compound used in the A layer and the B layer is blended. It can be judged by observing. It is not clear why the thermoplastic resin or adhesive has an electron accepting property and develops an electron-donating color-developing organic compound, but it is not possible to use electrons such as carboxylic acid groups or acrylic acid groups present in the thermoplastic resin or adhesive. It is considered to be due to the presence and concentration of donor groups, catalyst residuals, impurities such as residual monomers and residual oligomers, crosslinking agents and additives.

The thermoplastic resin can be heat-processed at a temperature not higher than the thermal decomposition temperature of the electron-accepting organic compound or the electron-donating color-developing organic compound. For example, branched low-density polyethylene, ethylene and α-C4-12. Linear low density polyethylene, high density polyethylene, which is a copolymer with olefin
Examples include copolymers of (ethylene and / or butene-1) and propylene, copolymers of (vinyl acetate and / or acrylate) and ethylene, olefinic thermoplastic resins such as polypropylene, and the like. They can be used alone or in combination of two or more. As the pressure-sensitive adhesive, conventionally known latex-based, natural rubber-based, SBR-based, polybutadiene-based, butyl rubber-based, synthetic rubber-based, etc. rubber-based adhesives, acrylic ester-based, etc. acrylic-based adhesives, silicon-containing System adhesive, silicone adhesive,
A urethane adhesive or the like can be used. As the type of the adhesive, any of an aqueous emulsion type, a solvent type, a non-solvent type, a cross-linking type, a non-cross-linking type and the like may be used. Generally, the higher the degree of crosslinking, the longer the discoloration period. The sizes of the A layer and the B layer may be appropriately different depending on the intended use. The sizes and shapes of the A layer and the B layer may be the same, but those having different sizes and shapes may be used to clarify the change in color tone. In this case, the portion where the A layer and the B layer are superposed is erased, and the portion of the A layer which is not overlapped is still colored.

The compounding amount of the electron-donating color-developing organic compound is
Although it can be arbitrarily changed in consideration of a desired color tone and effective period, it is usually 0.001 to 5 parts by weight with respect to 100 parts by weight of the layer A and an electron-donating color-forming organic compound. If the amount of the electron-donating color-developing organic compound is less than 0.001 part by weight, the discoloration is unclear, and if it exceeds 5 parts by weight, the crystal of the electron-donating color-developing organic compound is inside the layer A. Alternatively, it is not preferable because it is deposited on the surface.

The application of the present invention is not particularly limited and can be used by attaching to various products having a valid period. For example, the shelf life of products such as antifungal agents, herbicides, plant growth regulators, pheromone preparations, juvenile hormone mimetics, insecticides, repellents, deodorants, fragrances, pharmaceuticals, animal and plant essential oils, foods, etc. It can be known by the color change of the time indicator.

Although the color change period of the time indicator of the present invention varies depending on the use temperature, the diffusion of the electron-donating color-developing organic compound in the A layer and the B layer, and the distribution of the electron-donating color-changing organic compound. It can be controlled by factors such as the coefficient and the thickness of the A layer and the B layer, and can be arbitrarily set within a period of several hours to several years. The lower the diffusivity in the A layer and the B layer, the smaller the distribution coefficient, the larger the thickness of the A layer, and the smaller the thickness of the B layer, the longer the discoloration period of the time indicator becomes. Furthermore, in order to control the discoloration period, the layer A and / or the layer B may be a multilayer body having on one or both sides thereof a layer made of a thermoplastic resin or a pressure-sensitive adhesive permeable to an electron-donating color-forming organic compound. Good.

[0015]

EFFECTS OF THE INVENTION According to the present invention, the discoloration period is not affected by the use environment, the color is less likely to fade, the discoloration period can be easily controlled, and environmental pollution due to volatilization of additive components into the use environment. Therefore, it is possible to provide a very useful time indicator that can be used by being attached to a product having a shelf life for a wide range of applications.

[0016]

The present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. Example 1 As a layer A, 8 type 2 type 3 layer film formed by the following method was used.
It was cut into cm squares for use. Ethylene-methyl methacrylate copolymer (Sumitomo Chemical Co., Ltd. Acryft WH202)
100 parts by weight and 0.04 parts by weight of Rhodamine B base (manufactured by Taoka Chemical Industry Co., Ltd.) were melt-kneaded by using a shearing heat generator in a closed pressure kneader, and then hot-cut while being supplied to an extruder and extruding. It was made into pellets. Subsequently, a multi-layer inflation device equipped with a three-kind three-layer inflation die was used, and the medicinal effect indicating resin composition was melted in an intermediate layer of the die at a melting zone of 170 ° C and a die temperature of 150 ° C.
It was supplied under the conditions of. Low density polyethylene (Sumikasen CE255 manufactured by Sumitomo Chemical Co., Ltd.) is used for both the inner and outer layers.
9) was fed under the conditions of a melting zone of 180 ° C and a die temperature of 150 ° C. The resin supplied to each layer is bonded inside the die, and the tubular body of three-layer sandwich structure (outer layer / intermediate layer / inner layer) is taken off at a take-up speed of 4.2 m / min, and the thickness of each layer is 10 μm / outer layer A two-kind, three-layer film having an overall thickness of 50 μm, which was composed of 30 μm layer / 10 μm inner layer, was obtained. As the B layer, linear low density polyethylene (Sumitomo Chemical Co., Ltd.)
Made, product name: Excellen VL VL200) thickness 10
A 0 μ, 5 cm square press sheet was used. After layer A and layer B are overlaid, layer A and layer B are overlaid with polyethylene terephthalate film (10 cm square, 10 cm
After sandwiching (0 μ thickness) (hereinafter referred to as PET), the end surface of PET was fixed with an aluminum tape, and changes with time in color tone at 20 ° C. and 40 ° C. were observed. The superposed layers A and B were initially transparent, but the layer B gradually developed a reddish purple color. The color change period at this time is shown in Table 1.

Example 2 As a B layer, a PET-based adhesive (manufactured by Lintec Co., Ltd.,
The time-dependent change in color tone at 20 ° C. and 40 ° C. was observed in the same manner as in Example 1 except that Super Stick PET38CLLS0082PET3801) was used. The superposed layers A and B were initially transparent, but the layer B gradually developed a reddish purple color. The color change period at this time is shown in Table 1.

Comparative Example 1 The procedure of Example 1 was repeated except that a press sheet (100 μm, 5 cm square) of ethylene-methyl methacrylate copolymer (Aklift WH202 manufactured by Sumitomo Chemical Co., Ltd.) was used as the B layer. The change with time of the color tone at ℃ and 40 ℃ was observed. This ethylene-methyl methacrylate copolymer (Aklift WH202 manufactured by Sumitomo Chemical Co., Ltd.) does not have an electron accepting property for coloring rhodamine B base, and no color change was observed during the observation period.

Comparative Example 2 As the B layer, a PET-based adhesive (manufactured by Lintec Co., Ltd.,
The time-dependent change in color tone at 20 ° C. and 40 ° C. was observed in the same manner as in Example 1 except that Super Stick PET38CLWP (3) PET3801) was used. This PET-based adhesive (Lintec Co., Ltd., Supertech PET38CLWP (3) PET380
1) did not have an electron accepting property for coloring rhodamine B base, and no color change was observed during the observation period.

[0020]

[Table 1]

Claims (5)

[Claims] 1. A partition coefficient between layers A and B made of a thermoplastic resin or a pressure-sensitive adhesive when the layers are superposed on each other [distribution coefficient = electron-donating color-forming organic compound in layer B at distribution equilibrium]. Compound concentration) / (concentration of electron-donating color-developing organic compound in A-layer at distribution equilibrium)] of 0.1 or more, and layer A is in a decolored state containing an electron-donating color-developing organic compound When,
When the layer B having an electron accepting property and in the decolored state is superposed, the color of the layer B becomes darker with time, and it is possible to show the passage of time after superposing both layers. Time indicator to turn on. 2. A multi-layered body having layer A and / or layer B which has a layer made of a thermoplastic resin or a pressure-sensitive adhesive permeable to an electron-donating color-developing organic compound on one side or both sides thereof. Time indicator. 3. A barrier layer which is impermeable to an electron-donating color-forming organic compound and is laminated on one surface of each of the A layer and the B layer, which is an outer surface when the A layer and the B layer are superposed. The time indicator shown. 4. The time indicator according to claim 1, wherein the layer A and the layer B, which are superposed on each other, are covered with a barrier layer which does not allow the electron-donating color-forming organic compound to pass therethrough. 5. An electron-donating color-developing organic compound is a rhodamine lactam, a fluorane, a triphenylmethanephthalide, a phenothiazine, an indolylphthalide, a spiropyran, a leukoauramine, or a compound thereof.
The time indicator according to claim 1, which is a mixture of two or more species.