JPH0644046B2 - Period elapsed display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a time-lapse indicator, and in particular to certain processed foods (improved noodles, oil confectionery, half-baked confectionery, etc.),
Effective for pharmaceuticals (antibiotics, vaccines, etc.), insect repellents, deodorants, bactericides, refrigerant gases, films and photographic papers, photosensitive papers, cosmetics, batteries, oils, chemicals that are sensitive to visible light and X-rays. Applicable to products for a limited period of time, or blood or components of blood for transfusion that also have a limited effective period,
The present invention relates to a time-lapse indicator (hereinafter referred to as a "time indicator" or simply "indicator") that enables the user to know at a glance whether or not it is within its valid period.

(Prior Art) The following is a method for expressing a period such as an expiration date of a product. For example, in a volatile drug, the active ingredient may be in the form of a solution or wax, and volatilization of these may be visually observed from the outside of the container. This type cannot be applied to all products because the properties of the active ingredient itself are limited to volatile ones. Regardless of the active ingredient, there are indicators that use the volatility of the substance as an indicator of the period, and the degree of coloring decreases due to volatilization of colored liquids (including those absorbed in gel) and volatilization of sublimable dyes. There is something to see. However, the volatilization of substances is greatly affected by temperature and humidity, and it is difficult to show an accurate period, and the volatilized substances may contaminate the surrounding air.

As another example, a time indicator that can judge the elapsed time by light, temperature, humidity, or a color change due to a gas such as oxygen (O ₂ ) or carbon dioxide (CO ₂ ) in the atmosphere can be considered.

However, light, temperature, humidity, etc. change greatly in daily life, so the time indicator using these changes color even before the scheduled period has passed, or even after the scheduled period has passed. It may be difficult to obtain a stable time indicator because the color does not change. In addition, a colorant that changes its color depending on the amount of O _{2 in} the atmosphere, such as methylene blue, is placed in a bag made of a plastic film having a certain amount of oxygen permeability, and the plastic film is sealed in a vacuum state. A method of changing the color of the coloring agent by O ₂ penetrating and penetrating and measuring the elapsed time has also been studied.
Generally, the oxygen transmission rate of a plastic film changes depending on the ambient temperature and humidity, and thus it is difficult to obtain a stable time indicator that can always measure the passage of a certain period.

Further, by using CO ₂ instead of O _2, a bag made of a plastic film having a certain amount of carbon dioxide gas permeability is filled with a colorant that changes color depending on the change of pH of the atmosphere, and the bag is sealed in a vacuum state. There is also a method of changing the color of the colorant by changing the pH of the atmosphere caused by CO ₂ penetrating through this plastic film, but this time indicator is the effective period of the fragrance, deodorant, insect repellent, etc. , It has the drawback that it can not display the period of several months to several years and changes color in a shorter time (several hours to several tens of hours), and it is sensitive to the influence of humidity. Cannot be used as an indicator to show the passage of time.

(Problems to be Solved by the Invention) For the purpose of solving the above problems, the present inventors encapsulated a highly viscous liquid or gel-like substance in a container, and placed the encapsulated substance in a part of the container. We have previously proposed a stable time-lapse indicator that is not affected by light, humidity, or other atmospheric gases by having a structure in which a coloring substance that causes coloring or discoloration is localized.

This period progress indicator uses the diffusion of the dyeing substance into the highly viscous liquid or gel-like substance, and the dyeing substance moves and colors in the highly viscous liquid or gel-like substance with the passage of time. It is intended to display the period according to the amount or the length. However, since this time-lapse indicator uses the diffusion of the dyeing substance, a visible concentration gradient is generated at the tip of the diffusion, and it is difficult to confirm the tip clearly. It was an error.

(Object of the invention) Therefore, the present invention can display the effective period of products such as insect repellents, fragrances, and deodorants, that is, the progress of a period of several days to several months, and further, in the presence of light, humidity and other atmospheres. Invented as an indicator that is not easily affected by the factor of 1., a highly viscous liquid or gel-like substance is enclosed in a container, and a dyeing substance for coloring or discoloring the enclosed substance is localized in a part of the container. The purpose of the present invention is to eliminate the ambiguity of the diffusion tip due to the concentration gradient at the time of diffusing the dye substance in the time-lapse indicator, and to eliminate the error when reading the time passage.

(Means for Solving Problems) That is, according to the present invention, a highly viscous liquid or a gel-like substance is enclosed in a container, and a dyeing substance for coloring or discoloring the enclosed substance is localized in a part of the container. In the time-lapse indicator, the agar gel is used as the gel-like substance and methylene blue is used as the dyeing substance.

As a result, the concentration gradient at the diffusion front becomes extremely small visually, and the front end for displaying the period becomes clear, so that it is possible to eliminate an error when reading the passage of the period.

(Detailed Description of the Invention) Hereinafter, an embodiment in which a cylindrical object is used as a container will be described with reference to the drawings in order to easily understand the present invention.

1 (a) and 2 (b) are cross-sectional explanatory views for easily understanding the present invention. Body (1) and lid (2)
Indicates a tubular body. The inside of FIG. 1 (a) is filled with a developed product (3) of agar gel, and inside the lid (2) is methylene blue (4) which is a staining substance for coloring the developed product (3). It is filled. A cutout line (6) for exposing the developed product (3) is provided on the main body (1) of the tubular body, and the lid of the tubular body is provided for sealing the filled dye substance (4). A sealing cap (5) is attached.

At the start of the period display of the tubular body composed of these two parts, the user cuts the main body (1) along the cutting line (6) and removes the sealing cap (5) of the lid body (2), as shown in FIG. Display can be started by combining as shown in FIG. At the end of the period, since the dyeing substance (4) of the lid (2) diffuses into the developed product (3) of the main body (1), it appears that the main body (1) is colored in appearance. It is possible to indicate the end of the period when the main body (1) is completely colored or when a mark is put on the main body (1) and the part is colored.

In such a time-lapse indicator, various highly viscous liquids or gel substances can be used as the developed product (3), and various dyes can be selected as the dyeing substance (4). At this time, as the highly viscous liquid or gel-like spread (3), for example, carboxymethyl cellulose, sodium alginate gel, starch, gelatin, polyvinyl alcohol, polyacrylic acid gel, polyacrylamide gel, etc. are used, and methylene blue is used as the staining substance (4). FIG. 2 (a) is a schematic diagram showing diffusion when the was developed. Also, when agar gel was used for the gel-like spread (3) and Congo red, aniline blue, malachite green, etc. were used as the staining substance (4), almost the same diffusion as in the state shown in FIG. 2 (a) was exhibited. It was Furthermore, the combination of the developed product and the dyed substance was changed, and the results were the same. In this way, when the dyeing substance diffuses into the developed product, it is common to generate a band of density. However, it is not known in detail why such diffusion occurs, but only when the agar gel was used as the developed product (3) and methylene blue was used as the staining substance (4), as shown in FIG. Was found to diffuse in a clear state.

In this way, the tip of the diffusion of the dyeing substance can be clearly seen through the cylindrical body (1), so that the user of the period display can reduce the reading error during the period.

Here, the tubular body to be used in the present invention includes polyethylene, Teflon, acrylic resin, polycarbonate, silicon tubes, glass tubes, etc., and transparent or light colored ones whose contents can be visually observed from the outside are desirable.

〔Example〕

As a dyeing substance, methylene blue 0.5 part (weight part: hereinafter, the ratio is expressed by weight part), prepared with a ratio of 99.5 parts of water, was enclosed in a polyethylene tube having an inner diameter of 5 mmφ and a length of 2.5 cm. , Agar and water were adjusted at the ratio (weight ratio) shown in Table 1 as the developed product, and the inner diameter was 3 mmφ and the length was 8
Each was enclosed in a polyethylene tube of cm. When the two are brought into contact with each other at the start of display, the dye substance diffuses and stains in the developed product, so that the period can be displayed. Table 1 also shows the display period when the dye moves 8 cm.

Further, this indicator can also indicate the progress of the period shown in Table 1 by marking the scale on the tubular body containing the developed product. The change over time in the diffusion movement of each indicator is shown in FIG.

(Effects of the Invention) According to the elapsed time display of the present invention, a stable indicator that is not easily affected by light, humidity, and other factors in the atmosphere was obtained. Also, the ambiguity of the diffusion tip due to the concentration gradient when the dyeing substance is diffused is eliminated, and the display becomes clear,
It became possible to eliminate the error when reading the elapsed time.

In addition, the time-lapse display of the present invention tends to speed up the period display at a high temperature as compared to a low temperature, but a product whose lifetime is desired to be measured often deteriorates at a high temperature, which is just right. become.

[Brief description of drawings]

FIG. 1 (a) is a cross-sectional explanatory view showing one embodiment of the period elapsed display body of the present invention. FIG. 1 (b) is a sectional explanatory view showing an example of use of the period elapsed display body of the present invention. FIG. 2 (a) is a schematic diagram showing the state of diffusion of the dyeing substance in the example of the conventional time-lapse display body, and FIG. 2 (b) is the diffusion state in the embodiment of the time-lapse display body of the present invention. It is a schematic diagram which shows a mode. FIG. 3 is a graph showing the change with time of the diffusion of the dye in the time-lapse indicator of the present invention. (1) Cylindrical body (main body) (2) Cylindrical body (lid) (3) Expanded product (4) Dyeing substance (5) Sealing cap (6) Cut line (7) Diffusion tip of dyeing substance

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Japanese Patent Laid-Open No. 1-141973 (JP, A) Actual Development Sho 62-180756 (JP, U) Japanese Patent Sho 57 57992 (JP, B1)

Claims (2)

[Claims] 1. A time-lapse indicator in which a highly viscous liquid or gel-like substance is enclosed in a container, and a dyeing substance for coloring or discoloring the enclosed substance is localized in a part of the container. A period-lapse indicator, wherein agar gel is used as the gel substance and methylene blue is used as the staining substance. 2. The period progress indicator according to claim 1, wherein the container is a tubular body.