CN1119779C - Indicator - Google Patents

Abstract

The present invention relates to an indicator which is made of a porous resin body and liquid contained in the pore parts of the porous resin body, wherein the porous resin body has a whiteness degree higher than 80, and the whiteness degree of the porous resin body is at least 20 higher than that of the indicator. The indicator can display a period by a change in color tone. Thus, the persistency of indication performance is good, and the variation of the displayed period is little.

Description

indicator

technical field

The present invention relates to an indicator displaying duration information by color tone change.

Background technique

Known utensils for displaying duration at present are to utilize the phenomenon that when liquid is kept on the surface layers of frosted glass or water book paper, the color is different from that before keeping (Japanese Patent Publication No. 63-13545). However, this known method only keeps the liquid on the surface layer of ground glass or water book paper. During the transportation of the duration indicator or the storage period in a sealed state before use, the liquid will evaporate, lose or transfer to other places. Substances, so that the amount of liquid held by the duration indicator at the beginning of use decreases, the color begins to change during storage, or the indicated duration of use deviates. In addition, due to the small amount of liquid retained, when used When the liquid is insecticide or fragrance, etc., they will not work well.

Contents of the invention

It is an object of the present invention to provide an indicator that has good shelf life and has a small error in display duration during use.

The present invention relates to an indicator which is composed of a resin porous body and a liquid held in the pore portion of the resin porous body and satisfies the following relational expression:

W ₁ ≥ 80 and (W ₁ −W ₂ ) ≥ 20 In the formula, W ₁ represents the whiteness of the resin porous body, and W ₂ represents the whiteness of the indicator.

The indicator described in the present invention is a device for displaying duration, and can be used for various purposes as described below.

Brief description of the drawings

Fig. 1 is a cross-sectional view showing an example of use of a pointer.

Fig. 2 is a perspective view showing another usage example of the pointer.

Fig. 3 is a cross-sectional view showing a colored indicator.

Fig. 4 is a cross-sectional view showing another usage example of a colored indicator.

Fig. 5 is a cross-sectional view showing still another usage example of the indicator.

Detailed ways

In the present invention, a resin porous body having a whiteness of 80 or higher is used as the porous resin body. The whiteness of the resin porous body mentioned here refers to the whiteness W specified in JIS L 0803, which is measured in a state where the liquid is not maintained.

The type of resin used in the resin porous body is not particularly limited, and examples thereof include polyolefin-based resins, polyamide-based resins, polyacetal resins, polyester-based resins, fluorine-containing resins, polyvinyl chloride-based resins, polyphenylene-based resins, and polyvinyl chloride-based resins. Vinyl resin, methacrylic resin, polycarbonate, polysulfone, polyurethane resin, etc.

Among them, thermoplastic resins, especially polyolefin-based resins, are preferred.

Examples of polyolefin-based resins include α-olefin homopolymers such as low-density polyethylene, high-density polyethylene, polypropylene, and polybutene, and copolymers of ethylene, vinyl acetate, and/or (meth)acrylates. Copolymers of ethylene with ethylenically unsaturated bonds and organic carboxylic acid derivatives, copolymers of ethylene with at least one α-olefin (3-18 carbon atoms), propylene with ethylene and/or butene-1 Copolymer etc.

The resin porous body having a whiteness of 80 or more can be produced from a selected resin by any conventionally known method. For example, the following methods can be used: dissolving the resin and the low-molecular compound in a solvent, then evaporating the solvent to obtain a casting film, and extracting only the low-molecular compound from the casting film; using a blowing agent or using gas foaming A method of foaming a resin; a method of eluting one of the resins with a solvent after stretching a composition composed of two or more thermoplastic resins; molding a composition composed of a thermoplastic resin and a filler, and stretching the obtained A molded body, a method of obtaining a porous resin body, and the like.

Among them, the method of stretching a molded body composed of a thermoplastic resin and a filler can obtain a resin porous body with a high liquid holding capacity, and thus is preferably used.

From the viewpoint of the liquid retention rate of the obtained resin porous body, the porosity should be at least 0.01 cc/g, preferably at least 0.1 cc/g.

In this case, the proportioning of the thermoplastic resin and the filler, for example, the volume percentage of the filler is 5-60%, preferably 15-40%, and most preferably 23-35%, so that the obtained resin is porous The porosity of the body is more favorable. In addition, the volume percentage of a filler is calculated|required from the weight percentage conversion of a filler using the specific gravity of resin and the specific gravity of a filler.

The average particle size of the filler is, for example, 100 μm, preferably 0.05-10 μm. A molded article made of a thermoplastic resin and a filler can be produced by a known method, for example, by mixing the thermoplastic resin and the filler using a roller type or Banbury type mixer, or a single-screw or twin-screw extruder or the like or Knead, then extrude into shape.

In order for the indicator to change color to a greater extent, the filler should satisfy the following relationship (1) for the refractive index.

(1) Refractive index of thermoplastic resin/refractive index of filler = 0.89 to 1.13 The refractive index ratio in the formula (1) is preferably 0.98 to 1.02.

The kind of filler is not particularly limited, for example can enumerate: Inorganic fillers such as calcium carbonate, silicon oxide, silicate, hydrotalcite compound, lithium aluminum hydroxide, sodium chloride; Nylon powder, polycarbonate powder, Polystyrene powder, cross-linked polystyrene powder, polypropylene powder, polymethyl methacrylate powder, poly-4-methylpentene-1 powder and other organic fillers.

For example, when polyolefin resin is used, inorganic fillers are preferably used, among which hydrotalcite-based compounds and lithium aluminum hydroxide are particularly preferred.

Examples of hydrotalcite compounds include compounds represented by the following formula

[M ²⁺ _1-X M ³⁺ _X (OH) ₂ ] ^X+ [A ₁ ^n- _X/n ·mH ₂ O] ^X- In the formula, M ²⁺ represents a divalent metal cation, and M ³⁺ represents 3 Valence metal cations, A ₁ ^n- represents n-valence anions, X is a number of 0<X≤0.33, m is a number of 0≤m≤2.

Divalent metals include magnesium, manganese, iron, cobalt, nickel, copper, zinc, etc., trivalent metals include aluminum, iron, chromium, cobalt, indium, etc., and n-valent anions include hydroxide ions, carbonate ions, fluoride ions, chloride ions, bromide ions, nitrate ions, sulfate ions, etc. It is also possible to replace n-valent anions with organic anions.

Examples of lithium aluminum hydroxide include compounds represented by the following formula

Li ⁺ (Al ³⁺ ) ₂ (OH) ₆ ·(A ₂ ^n- ) _1/n ·mH ₂ O In the formula, A ₂ ^n- represents an anion with a valence of n, n is an integer from 1 to 4, and m is 0 ≤m≤3 number. The type of n-valent anion is not particularly limited.

Among the above-mentioned filling materials, hydrotalcites are preferred.

The conditions and method for stretching the molded body can be appropriately selected according to the type of resin used for the porous resin body. For example, when polyethylene is used, stretching is performed at a stretching ratio of 1.1 to 10 times in a stretching temperature range of 30 to 130°C. Examples of the stretching method include the roll-to-roll stretching method.

A resin porous body having a whiteness of at least 80, preferably at least 90 can be obtained by appropriately selecting the amount of the filler, the thickness of the molded body, the stretching ratio, and the like.

The thickness of the resin porous body is not particularly limited, and may be, for example, 10 μm to 1 mm. From the viewpoint of increasing the degree of discoloration of the indicator, the thickness of the resin porous body is usually 10 to 500 μm, preferably 50 to 500 μm, most preferably 100 to 500 μm.

The choice of liquid should satisfy the following relational formula (2) of the refractive index.

Refractive index of liquid/refractive index of thermoplastic resin = 0.867 to 1.13 (2) In order to make the difference between the whiteness of the indicator described later and the whiteness of the resin porous body and the degree of discoloration of the indicator larger, the formula (2) The refractive index ratio is preferably 0.96 to 1.04.

The kind of liquid is not particularly limited. As long as it is liquid at the use temperature, does not dissolve the resin porous body, and can be evaporated or eluted from the resin porous body, it can be appropriately selected according to the purpose of use, the duration of display, and the method of use.

Said liquid, for example, can include at least one organic compound or fungicides, bactericides, herbicides, plant growth regulators, pheromones, insect repellants, insect growth inhibitors, insect repellents, fragrances, medicines, etc. at least one of the active ingredients.

In addition, the above-mentioned liquid may also be a liquid that has dissolved an effective active ingredient that is solid at the temperature at which the indicator is used. ) liquid dissolved in butanobutanol (a compound that has the effect of increasing the effect of insecticidal active ingredients), in addition to the function of the indicator, it can also obtain the effect of insecticidal activity.

Examples of organic compounds or effective active ingredients include alcohols such as ethanol and isopropanol; ketones such as methyl ethyl ketone; ethers such as tetrahydrofuran and dioxane; fats such as hexane, decane, kerosene, and liquid paraffin Aromatic hydrocarbons such as toluene and xylene; ethyl acetate, butyl acetate, benzyl acetate, ethyl myristate, phthalate, diethyl phthalate, phthalate Dibutyl formate, dioctyl phthalate, benzyl benzoate and other esters; dichloromethane, dichloroethane and other halogenated hydrocarbons; Japanese cypress essential oil, cypress essential oil, soybean oil, rapeseed oil, Animal and vegetable oils such as salad oil; aromatic liquids such as lemongrass oil, orange oil, lavender oil, mustard oil; phenols such as resorcinol and o-cresol; phenolic carboxylic acids such as salicylic acid; benzyl alcohol, methanol Other alcohols; p-chlororesorcinol, o-phenylphenol, 3-methylisopropylphenol, 3-acetyl-6-methyl-2-pyrone, benzoic acid, hydroxybenzoate and other fungicidal and bactericidal active ingredients; Phenothrin, d-resmethrin, empentrin, fenvalerate, fenvalerate, siharotrin, cypermethrin, bifenthrin Pyrethroid compounds such as Enprox, Traromesrin, Esbiosrin, Transfurthrin, and Tetraresrin; Fenetrochon, Dichlorvos , dibromophos, fenthion (Fenchion), cypronil, trichlorfon (croulpilhos), diazinon, calcium dichlorvos (calcrophos), salicylphos, diazinon and other organophosphorus compounds; methoxy Carbamate compounds such as diazo (Metokishijazon), propoxycarb (Proboxol), BPMC, carbaryl; insect repellant active ingredients such as phenylpyridine compounds; Insect growth inhibitory active ingredients such as mesopuren, hydrogenated juvenile, hexamethasone, cyromajin, phenoxyalkyne propanil (feenokisika-bu), and verbenzuron (lufenuron); diethyl Toluamide insect repellent active ingredients, etc.

The method of retaining the liquid in the resin porous body includes, for example, a method of immersing the resin porous body in the liquid, and a method of coating the liquid on the surface of the resin porous body. In addition, when a resin porous body is produced by stretching a molded body composed of a thermoplastic resin and a filler, a method of stretching in a state where the molded body is immersed in a liquid or in a state where a liquid is applied to the molded body may also be used. , or a method in which a liquid is contained in a molded body in advance by means of kneading or the like, and then stretched.

In this way, the liquid can be retained in the resin porous body having a whiteness of 80 or more, and an indicator having a whiteness of 20 or more smaller than the resin porous body can be obtained. The whiteness of the above-mentioned indicator is the same as the whiteness of the porous body, which is the whiteness W specified in JIS L 0803, and is measured while maintaining a liquid in the porous body.

The indicator of the present invention is extremely easy to handle because the indicator of the present invention is less likely to adhere to the surface of the indicator as compared with the conventional indicator that retains the liquid in the surface layer.

The liquid content (liquid retention rate) of the resin porous body depends on the porosity of the resin porous body, and the indicator of the present invention may contain, for example, 15% by weight or more of liquid relative to the resin porous body.

When the whiteness of the indicator is 40 or more smaller than that of the resin porous body, the display of the duration is clearer and easier to distinguish.

The indicator whose whiteness is 40 or more smaller than the whiteness of the resin porous body can be manufactured as follows, for example, according to

Refractive index of thermoplastic resin/refractive index of filler = 0.98 to 1.02

Refractive index of liquid/refractive index of thermoplastic resin = 0.867 to 1.13 range Use a combination of thermoplastic resin, filler and liquid, make the volume percentage of the filler, for example, 15 to 40%, preferably 20 to 30%, choose appropriately stretching conditions.

Specific examples of the above combinations can be cited as follows:

Linear low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENE-L FA201-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Co., Ltd., DHT-4A)/EMPENTHRIN (synthetic pyrethrin);

Linear low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENE-L FA101-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Co., Ltd., DHT-4A)/EMPENTHRIN (synthetic pyrethrin);

Branched low-density polyethylene (manufactured by Sumitomo Chemical Industry Co., Ltd., SUMIKATHENEF208-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Industry Co., Ltd., DHT-4A)/EMPENTHRIN (synthetic pyrethrin);

Linear low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENE-L FA101-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Co., Ltd., DHT-4A)/diethyltoluamide;

Branched low-density polyethylene (manufactured by Sumitomo Chemical Industry Co., Ltd., SUMIKATHENEF208-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Industry Co., Ltd., DHT-4A)/diethyltoluamide;

Linear low density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENE-L FA101-0) / hydrotalcite compound (manufactured by Kyohappo Chemical Co., Ltd., DHT-4A) / EMPENTHRIN (synthetic pyrethrin) Dibutyl diformate (weight ratio 50/50);

Branched low-density polyethylene (manufactured by Sumitomo Chemical Industry Co., Ltd., SUMIKATHENEF208-0)/hydrotalcite-based compound (manufactured by Kyohappo Chemical Industry Co., Ltd., DHT-4A)/EMPENTHRIN (synthetic pyrethrin) phthalic acid Dibutyl ester (weight ratio 50/50);

Linear low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENE-L FA101-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Co., Ltd., DHT-4A)/dibutyl phthalate;

Branched low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENEF208-0)/hydrotalcite compound (manufactured by Kyohappo Chemical Industry Co., Ltd., DHT-4A)/EMPENTHRIN (synthetic pyrethrin)/phthalic acid Dibutyl ester.

Among the combinations of the above examples, the combination of hydrotalcite-based compounds and EMPENTHRIN (synthetic pyrethrin) is preferred from the viewpoint of the whiteness difference and the refractive index ratio defined by the relational formulas (1) and (2).

In addition, within the scope of not impairing the effects of the present invention, the resin porous body may contain substances for improving tensile properties, dispersants, light stabilizers, heat stabilizers, moisture absorbers, deodorants, fragrances, pigments, etc. , dyes, etc.

In addition, the above-mentioned resin may be used by mixing two or more types of thermoplastic resins having compatibility. Two or more types of fillers may be used in combination.

In this case, the above relational expressions (1) and (2) should be satisfied for all combinations of each thermoplastic resin, each filler and liquid.

That is, the combination should be selected using

The ratio of the refractive index of thermoplastic resin i/the refractive index of filler j

The ratio of the refractive index of the liquid/the refractive index of the thermoplastic resin i (i=1～n, j=1～m, n and m respectively represent the number of the thermoplastic resin used and the number of the filler used) satisfies the above-mentioned scope.

When using two or more kinds of thermoplastic resins, a preferable example can be mentioned, for example, the ratio of ethylene and at least one kind of α-olefin (4 to 12 carbon atoms) copolymer is 60% relative to the total amount of thermoplastic resins (weight) above. Most preferably, copolymers of ethylene and at least one alpha-olefin (4 to 12 carbon atoms), namely linear low density polyethylene 60 to 95% by weight and branched low density polyethylene 40 to 5% by weight ), a resin porous body with good strength and uniform porosity can be easily obtained by the method of stretching the molded body.

Copolymers of ethylene and one or more α-olefins (4 to 12 carbon atoms), such as linear low-density polyethylene (manufactured by Sumitomo Chemical Industries, Ltd., SUMIKATHENE-L FA201-0), linear low-density polyethylene Polyethylene (manufactured by Sumitomo Chemical Industries, Ltd., SUMIKATHENE-L FA101-0).

The usage method of the indicator of the present invention is not particularly limited, and the usage method can be determined according to the application.

For example: hang it in the closet to make the liquid evaporate and spread into the space; soak it in a solution with specific conditions such as a sink to dissolve the liquid; or contact or stick the material that has absorbed the liquid on the indicator , to enable liquid transfer, etc.

As time goes by, the liquid retaining part of the indicator of the present invention changes from a state of low whiteness (transparent) to a state of high whiteness (white), so that the duration can be reported.

As shown in Fig. 1, in the case where a colored layer B other than white is provided on at least one side of the transparent indicator A of the present invention, as time goes by, the indicator changes from the color of the colored layer to white, thereby reporting the passage of time. time. By adjusting the thickness of the indicator A, the color of the colored layer can be hidden when the indicator A is in a state of high whiteness (white), so that the end of time can be indicated more clearly. The thickness of such an indicator A varies depending on the color of the colored layer used and the desired degree of color tone change, and is, for example, 30 μm or more. Characters such as "please replace" may be printed in advance on the indicator A of the present invention using the same color as that of the colored layer B, or characters such as "in use" may be printed in white on the colored layer.

As shown in Figure 2, the words "in use" and "effective" are printed in black on both sides or one side of the white substrate. Using such a substrate material, the whiteness of the indicator A will change from The lower state (transparent) changes to the higher whiteness state (white), and characters such as "effective" cannot be read, so that it can be known whether the product has reached the end of its life.

As shown in FIG. 3 , in the case of the indicator C of the present invention colored in advance with a color other than white, the color changes from the colored color to a light color or to white as time passes. It is possible to use the same color as the indicator C, and write words such as "please replace" on the surface in advance by printing or the like. Or use printing and other methods to record white "in use" and other words.

As shown in FIG. 4, when the transparent indicator A of the present invention is arranged on at least one side of the indicator C of the present invention colored in advance with a color other than white, as time passes, the initial The color changes to white, and the elapsed time can be reported. In this case, not only the indicator A but also the indicator C become white, so the change in color tone is more conspicuous. The thickness of the indicator A varies depending on the color of the colored layer used and the desired degree of hue change, and may be, for example, 3 μm or more. In addition, it is possible to use the same color as the indicator C, and record characters such as "please replace" on the indicator A in advance by printing or the like, or record characters such as "in use" on the indicator C in advance by printing or the like.

As shown in Fig. 5, the indicator E of the present invention can also be laminated with a spreading layer F and a barrier layer G containing a liquid containing an effective active ingredient. The indicator of the present invention can also be used after being equipped with a release-controlling layer for controlling the release rate of the liquid in a more desirable range and a barrier layer for preventing the release of the liquid.

In the indicator of the present invention, these layers may be formed on the surface of the indicator by methods such as undersize lamination or extrusion lamination in order to hold the liquid in the pores of the resin porous body.

The controlled release layer, for example, can include a layer composed of at least one of the following: low-density polyethylene, high-density polyethylene, polypropylene, polybutene and other α-olefin homopolymers; ethylene and 3-18 carbon atoms Copolymers of at least one α-olefin; Copolymers of propylene and ethylene and/or butene-1; Organic carboxylic acids with ethylenically unsaturated bonds such as ethylene and vinyl acetate and/or acrylates and methacrylates Derivatives, copolymers, etc.

Barrier layer, as long as the permeability of the liquid used is low, different materials can be used according to the liquid used, such as glass, aluminum and other metal foils, metal plates, or ethylene-vinyl alcohol copolymers, nylon, polyparaphenylene A layer composed of one or more kinds of ethylene glycol diformate, polyvinylidene chloride, and the like.

The use of the indicator of the present invention is not particularly limited, for example, it can be used to indicate the effective period (for example, several hours to several years) of the product with a certain limit, or to indicate the cooking time (for example, 3 minutes) of bowl-packed instant noodles, etc. ).

Examples of products with a limited validity period include weed control tablets, insect repellent tablets, pheromone preparations, analgesics, transdermal therapeutic agents such as nicotine, antiseptic tablets, antirust tablets, fragrances used in cars and indoors, and repellents. Mosquito sheets, liquid repellents, insect repellent active ingredients contained in resins such as pet collars, slow-release preparations, paper and pulp used in wardrobes, insect repellents for clothing, refrigerators, and shoe cabinets Deodorants used in food, foods with shelf life, etc.

The length of time for discoloration varies depending on the configuration and usage conditions of the indicator used, and can range from tens of seconds to several years, for example. Under the same conditions of use, the color change time of the indicator is determined in advance, and the indicator suitable for the purpose of use can be selected.

The indicator of the present invention can retain a liquid in the pore portion, so compared with conventional products, the indicator hardly starts to change color during storage in a sealed state before use, and has good storage stability. In addition, the time deviation indicated during use is small, and it can contain a large amount of liquid, for example, it is easy to contain more than 15% (weight) of liquid, and when using insecticides or fragrances in liquid form, it can last for a long time. play their role.

Example

The present invention is illustrated by examples below, but the present invention is not limited by these examples. In addition, the measurement was performed by the method described below.

· Whiteness: Whiteness W specified in JIS L 0803, measured with an SM color computer (manufactured by Suga Testing Instrument Co., Ltd., model: SM-4).

·Liquid retention: Measured by gas chromatography.

· Discoloration time: evaluated by visual observation.

Example 1

Linear low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., SUMIKATHENE-L FA201-0) and a hydrotalcite compound (manufactured by Kyowa Chemical Co., Ltd., DHT-4A) were mixed, and the volume percentage of the hydrotalcite compound was 26%, kneading with a kneader (190°C, 5 minutes), extrusion molding (resin temperature 200°C), to obtain a sheet (thickness 0.55mm).

This sheet was unidirectionally stretched between rollers (stretching temperature 40°C, magnification 6 times), and heat-set at 90°C to obtain a resin porous body (thickness 0.22 mm, whiteness 97.2).

This resin porous body was cut into 5 cm squares, put into EMPENTHRIN (synthetic pyrethrin) (manufactured by Sumitomo Chemical Industry Co., Ltd., VAPORTHRIN) and dipped in, and 10 indicators were obtained (whiteness 54.8, EMPENTHRIN (synthetic pyrethrin) retained amount 30% by weight).

Put 5 indicators in a wardrobe drawer to use, very visibly change from clear to white. The discoloration time was 180 days ± 7 days, and a sufficient insect repellent effect was exhibited during this period.

Five indicators were sealed with film (manufactured by Kuraray Co., Ltd.) and stored at 23° C. for 180 days, but none of the indicators changed color.

Example 2

Combination of thermoplastic resins composed of linear low-density polyethylene (manufactured by Sumitomo Chemical Industries, Ltd., SUMIKATHENE-L FA101-0) and branched low-density polyethylene (manufactured by Sumitomo Chemical Industries, Ltd., SUMIKATHENE-L F208-0) (weight mixing ratio 8:2) and hydrotalcite compound (manufactured by Kyohei Chemical Industry Co., Ltd., DHT-4A) were mixed so that the volume percentage of the hydrotalcite compound was 26%, and mixed with a Banbury mixer. It was kneaded (140 degreeC, 5 minutes), and the resin composition T was obtained.

The resin composition T is supplied to the inner layer and the outer layer, 95% by weight of the resin composition T and 5% by weight of red coloring MB ( ^* a pigment) (manufactured by Sumikara-Co., Ltd., RED SPEM- 1E120) was supplied to the intermediate layer, and subjected to multilayer extrusion molding (resin temperature: 200° C.) to obtain a sheet (thickness: 0.24 mm).

The sheet was stretched between rollers in one direction (stretching temperature: 40°C, magnification: 6.5 times), and heat-set at 90°C to obtain a resin porous body (thickness: 0.12 mm, whiteness: 90.3).

The resin porous body was cut into 5 cm squares, and immersed in EMPENTHRIN (synthetic pyrethrin) (manufactured by Sumitomo Chemical Industries, Ltd., VAPORTHRIN) to obtain 11 transparent red indicators (whiteness 24.3, EMPENTHRIN (synthetic pyrethrin) ) Retention amount 33% (weight)).

When the 5 indicators were hung in a room with a temperature of 23°C and a humidity of 40%, they obviously changed from transparent red to white, and the color change took 7 days ± 0.5 days, showing sufficient insect repellent effect during this period.

Five indicators were sealed with film (manufactured by Kuraray Co., Ltd.) and stored at 23° C. for 180 days, but none of the indicators changed color.

Attach a PET (polyethylene terephthalate) base material (manufactured by Lindec Co., Ltd., SUPER STICK PET38CLWP(3)PET3801) with an adhesive to the indicator, and it changes from red to red 15 minutes after attaching. into white.

Example 3

Resin composition T was manufactured similarly to Example 2. Prepare a composition consisting of 95 parts (by weight) of resin composition T and 5 parts (by weight) of red MB (manufactured by Sumika Kara-Co., Ltd., RED SPEM-1E120), and perform extrusion molding (resin temperature 200° C.), A flake (thickness 0.24 mm) was obtained.

This sheet was unidirectionally stretched between rollers (stretching temperature 40°C, magnification 6.5 times), and heat-set at 90°C to obtain a resin porous body (thickness 0.12 mm, whiteness 82.5).

The resin porous body was cut into 5 cm squares, and immersed in EMPENTHRIN (synthetic pyrethrin) (manufactured by Sumitomo Chemical Industries, Ltd., VAPORTHRIN) to obtain 10 transparent red indicators (whiteness 24.9, EMPENTHRIN (synthetic pyrethrin) ) Retention amount 29% (weight)).

When the 5 indicators are hung in a room with a temperature of 23°C and a humidity of 40%, they obviously change from transparent red to opaque white, and the discoloration time is 7 days ± 0.5 days.

Five indicators were sealed with film (manufactured by Kuraray Co., Ltd.) and stored at 23° C. for 180 days, but none of the indicators changed color.

Except that the thickness of the sheet was 0.48mm, the same test was carried out to obtain an indicator (whiteness of resin porous body 82.7, whiteness of indicator 26.0, EMPENTHRIN (synthetic pyrethrin) retention 30% (weight) )). In the same evaluation, it was 14 days ± 1 day that the color change was evident, and there was no color change during storage.

Example 4

The liquid uses diethyltoluamide, except that the test is carried out in the same manner as in Example 2, and 10 transparent red indicators are obtained (the whiteness of the resin porous body is 90.3, the whiteness of the indicator is 20.0, diethyltoluene toluene Amide retention 33% by weight).

When the 5 indicators are hung in a room with a temperature of 23°C and a humidity of 40%, they obviously change from transparent red to opaque white, and the discoloration time is 7 days ± 0.5 days.

Five indicators were sealed with film (manufactured by Kuraray Co., Ltd.) and stored at 23° C. for 180 days, but none of the indicators changed color.

In addition, using EMPENTHRIN (synthetic pyrethrin)/dibutyl phthalate (weight ratio 50/50) instead of diethyltoluamide, the same test was carried out to obtain an indicator (whiteness 22.0, liquid retention Amount 31% (weight)). In the same evaluation, the color change was extremely conspicuous, and the elapsed time of discoloration was 60 days ± 2 days, and no discoloration due to retention was found.

Example 5

Linear low-density polyethylene (manufactured by Sumitomo Chemical Industries, Ltd., SUMIKATHENE-L FA101-0) and calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., trade name WHITONSSB (red) were mixed, and the volume percentage of calcium carbonate was 22%. The mixture was kneaded by a Banbury mixer (140° C., 5 minutes), and extruded (resin temperature: 240° C.) to obtain a film (thickness: 0.09 mm).

This film was unidirectionally stretched between rolls (stretching temperature: 40°C, magnification: 6 times), and heat-set at 90°C to obtain a resin porous body (thickness: 0.05 mm, whiteness: 92.3).

This resin porous body was cut into 5 cm squares, put into EMPENTHRIN (synthetic pyrethrin) (manufactured by Sumitomo Chemical Industry Co., Ltd., VAPORTHRIN) and dipped in, and 5 indicators were obtained (whiteness 72.3, EMPENTHRIN (synthetic pyrethrin) retained amount 20% by weight).

Hang 5 indicators in a room with a temperature of 23°C and a humidity of 40%, and change color within 3 days ± 0.1 days after use. The degree of discoloration is less than that of Examples 1-4.

comparative example

Titanium oxide (manufactured by DuPont, TAIPEK R101, refractive index 2.583, refractive index of thermoplastic resin/refractive index of titanium oxide=0.59) was used as filler, and the same operation was performed as in Example 5 to obtain a resin porous body (thickness 0.05 mm, whiteness 96.0).

In the same manner as in Example 5, dip in EMPENTHRIN (synthetic pyrethrin) (manufactured by Sumitomo Chemical Industries, Ltd., VAPORTHRIN) to obtain an indicator (whiteness 94.0, EMPENTHRIN (synthetic pyrethrin) retention 20% by weight) .

When this indicator was hung in a room with a temperature of 23°C and a humidity of 40%, the color did not change.

Example 6

A resin composition T was produced in the same manner as in Example 2, and the resin composition T was subjected to film blow molding at a resin temperature of 190° C. to obtain a film (thickness: 50 μm).

This film was unidirectionally stretched between rolls (stretching temperature 40°C, magnification 6 times), and heat-set at 90°C to obtain a resin porous body (thickness 12 µm, whiteness 91.3).

This resin porous body was cut into 5 cm squares and dipped in dibutyl phthalate to obtain an indicator (whiteness 28.7, dibutyl phthalate retention 25% by weight).

A PET substrate with an adhesive (manufactured by Lintec Co., Ltd., SUPER STICK PET38CLWP(3) PET3801) was attached to the indicator, and it changed from transparent to white clearly in 1 minute after the attachment.

Table 1

Filler porous body embodiment number category ¹⁾ volume percentage thickness W ₁ liquid embodiment 1 A 26% 0.22mm 97.2 EMPENTHRIN (combined

A 24% 0.12mm 90.3 EMPENTHRIN (Pyrethrin) Example 2

A 26% 0.12mm 82.5 EMPENTHRIN

A 26% 0.24mm 82.7 EMPENTHRIN

Polycin) Example 4 (1) A 24 % 0.12mm 90.3 Eroblyzolidide Implementation Example 4 (2) A 24 % 0.12mm 90.3 Empenthrin (Combined

Pyrethrins)

/ Dibutyl phthalate Example 5 B 22% 0.05mm 92.3 EMPENTHRIN (

C 22% 0.05mm 96.0 EMPENTHRIN

Pyrethrin) Example 6 A A 26% 0.012mm 91.3 Dibutyl phthalate

Table 1 (continued)

indicator

Example number W ₂ W ₁ -W ₂ Liquid retention Discoloration degree ²⁾

Example 1 54.8 42.4 30% ○○○

Example 2 24.3 66.0 33% ○○○

Example 3(1) 24.9 57.6 29% ○○

Example 3(2) 26.0 56.7 30% ○○

Example 4(1) 20.0 70.3 33% ○○○

Example 4(2) 22.0 68.3 31% ○○○

Example 5 72.3 20.0 20% ○

Comparative example 94.0 1.6 20% ×

Example 6 28.7 62.6 25% ○○○ Note: 1) A: DHT-4A (average particle size 0.4 μm)

B: WHITON SSB (average particle size 1.25μm)

C: TAIPEK R101 (average particle size 0.6μm)

2) ○○○: Large degree of discoloration

○○: Moderate discoloration

○: The degree of discoloration is small

×: no discoloration

Claims (4)

1. indicator is characterized in that, the liquid that keeps in the hole part by resin porous body and this resin porous body constitutes and satisfy the following relationship formula:

W ₁〉=80 and (W ₁-W ₂In the formula of) 〉=20, W ₁The whiteness of expression resin porous body, W ₂The whiteness of expression indicator.

2. the described indicator of claim 1, it is characterized in that, the resin porous body is to be made of the filling agent of the relational expression that satisfies following refractive index (1) and thermoplastic resin and the percentage by volume of filling agent is that formed body that 15～40% composition constitutes stretches and obtains, liquid is the liquid that satisfies following index of refraction relationship formula (2):

The refractive index of the refractive index/filling agent of thermoplastic resin=0.98～1.02 (1)

The refractive index of liquid refractive index/thermoplastic resin=0.867～1.13 (2)

3. the described indicator of claim 1 is characterized in that W ₁Be more than 80 or 80, and (W ₁-W ₂) be more than 40 or 40.

4. the described indicator of claim 2 is characterized in that, the ratio of relational expression (2) is 0.96～1.04.

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