JPS6219305B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a polymer laminate sheet,
More specifically, the present invention relates to a polymeric laminated sheet containing an active substance having physical and/or chemical activity and capable of releasing the active substance in a sustained manner.

As shown in FIG. 1, an active substance storage layer 1 made of a polymer containing a refractory or volatile active substance having physical and/or chemical activities such as pesticide activity, repellent activity, and aroma activity. a control layer 2 consisting of a polymer for controlling the release of this active substance on the surface;
It has a barrier layer 3 having barrier properties against active substances such as polypropylene, polyamide, polyethylene terephthalate, etc. on the back side, and further has an adhesive layer 4 on the exposed surface of the barrier layer, and has a desired adhesive layer. Various functional polymer laminate sheets are known that are adhered to a surface to allow sustained release of an active substance from the surface of a control layer or to transfer an effective concentration of an active substance to the surface of a control layer.

However, especially when the active substance is volatile, none of the polymers conventionally used as control layers are able to control the sustained release of the active substance satisfactorily, and the sustained release function is not sustained over a long period of time. In addition, in order to prolong the sustained release function,
It has also been attempted to include an excess of active substance in the storage polymer layer, but this method is uneconomical, especially since the amount of active substance released, especially initially, unnecessarily exceeds the effective level. Some types of substances can even be harmful.

In addition, in such conventional polymeric laminated sheets, in order to form an active substance storage layer, the active substance is dispersed in plastisol and this is applied to a synthetic resin film, or a solution of the active substance is applied to a synthetic resin film. It is applied to a film and dried,
Requires multiple steps.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a method for producing a polymer laminate sheet that enables sustained release of active substances over a long period of time.

The method for producing a polymer laminate sheet according to the present invention includes:
A barrier layer consisting of a metal layer, a resin layer, or a laminate thereof having barrier properties against the active substance is adhered to the two surfaces of the polymer layer in which the active substance is dissolved, and thus It is characterized in that the active substance is sustainedly released only from the sides of the polymer layer that are not covered by the barrier layer.

In the present invention, an active substance refers to a substance that has physical and/or chemical activity, and active substances include chemical activity including pesticide activity such as insecticidal, sterilizing, antifungal, repellent, and attracting activity, and physical activity such as aroma. Examples include, but are not limited to, physical activities such as chemical activity, electrical conductivity, and antistatic properties.

Specific examples of active substances include 2,2-dichlorovinyl phosphate (DDVP), organophosphorus and pyrethroid insecticides such as Sumithion, fungicides such as P-chloro-m-xylenol, and diethyltoluamide (DET). ), etc., mosquito, tick, and cockroach repellents, pheromones, attractants such as methyleugenol, limonene, benzyl alcohol, carbon number 6~
Mention may be made of perfume substances such as esters, ethers and aldehydes derived from 16 hydrocarbons.

In the present invention, the polymer in which the active substance is dissolved and contained is a synthetic resin, natural rubber, synthetic rubber, or any of these which can dissolve and contain the active substance at a concentration of 5% by weight or more, preferably 10% by weight or more at a temperature of 15°C. A mixture is preferable, and various types are used depending on the type of active substance, but specific examples include polyvinyl chloride, ethylene-vinyl acetate copolymer with a vinyl acetate content of 12% by weight or more, and acrylic acid with a content of 15% by weight. % or more of ethylene-acrylic acid copolymer, styrene-butadiene rubber, ethylene-propylene rubber, styrene-isoprene-styrene block copolymer, natural rubber, thermoplastic urethane elastomer, and mixtures of two or more of these. can. When the polymer is polyvinyl chloride, the polymer may contain a plasticizer such as dioctyl phthalate.

The content of the active substance in these polymers is appropriately determined depending on the type of active substance and polymer used, the purpose of the polymer laminate sheet, the conditions of use, etc., but in the case of agricultural chemicals, fragrances, etc. ~50% by weight, preferably 10-50% by weight. If the content of the active substance is too low, the activity expressed by the laminate is small and the duration of the activity is short, making it impractical for some applications, while on the other hand, if the content of the active substance is too high. This is because it becomes difficult to form into a sheet.

In the present invention, the barrier layer is not particularly limited as long as it has barrier properties against the active substance, but it is usually made of a metal foil such as aluminum foil or copper foil, a laminate of a resin film and these metal foils, or a layer of aluminum on a resin film. A laminate in which a vapor-deposited metal film of copper or the like is formed is used. As the resin film, metal foil or vapor-deposited metal film exhibits barrier properties, so there are no particular limitations, and for example, polyethylene, polypropylene, polyethylene terephthalate, polyamide, ethylene-vinyl alcohol copolymer, etc. can be used, but preferably Polyethylene terephthalate, polyamide, and ethylene-vinyl alcohol copolymer are used. In addition, cellophane, ethylene-vinyl alcohol copolymer,
Polyethylene terephthalate, polyvinylidene chloride, polyamide, etc. can be used alone as a barrier layer. It should be noted that the barrier layers adhered to the two surfaces of the layer of polymer containing the active substance may be the same or different.

In the present invention, a barrier layer is adhesively bonded to the two surfaces of the layer of polymer containing the active substance. The adhesive used is not particularly limited, but acrylic oxygen, acrylic acid ester, copolymer thereof, synthetic rubber, natural rubber, or adhesives or adhesives made of two or more of these are preferably used.

FIG. 2 shows a polymeric laminate sheet obtained by the method of the invention, in which a polymer layer 1 containing an active substance is covered on both sides with a barrier layer 3 adhered with an adhesive layer 5. . The method of the present invention requires that the side surface area of the polymer layer be sufficiently small compared to the surface area and volume of the polymer layer. As a result, according to the polymer laminated sheet obtained by the method of the present invention, the active substance is prohibited from being released from the surface and is released only from the side, so that the initial release rate is not unnecessarily increased and the active substance is released from the side. , it is possible to keep the release rate approximately constant over a long period of time, thus significantly increasing the duration of sustained release of the active substance at effective levels.

Incidentally, when the polymer laminated sheet is used by being attached to furniture, floors, walls, etc., an adhesive layer is provided on the surface of one of the barrier layers as necessary.

According to the method of the present invention, as described above, an active substance is dissolved and contained in a polymer, this is formed into a sheet, and then a barrier layer is bonded to the two surfaces with an adhesive. Since a composite laminated sheet is manufactured, unlike the conventional method described above, the number of steps is significantly reduced and the manufacturing cost is also low.

Examples of the present invention are listed below, but the present invention is not limited to these Examples. In addition, in the following examples, parts indicate parts by weight.

Example Fragrance (Fragrance GARDENIA HH manufactured by Takasago Fragrance Co., Ltd.)
-2942) 100 parts and ethylene-vinyl acetate copolymer resin (P3307 manufactured by Mitsui Polychemical Co., Ltd.) 400 parts
After kneading the mixture with hot rolls, it was formed into a sheet with a thickness of 1 mm using a press. Adhesive tape (adhesive tape No. 31 manufactured by Nitto Electric Industries, Ltd.) having a polyester base material was attached to both the front and back surfaces of this sheet to obtain a polymer laminate sheet. This sheet was cut into 10 cm x 10 cm pieces, placed in constant temperature baths at 40°C and 50°C, and the weight loss based on the release of each fragrance was measured. The results are shown in Figure 3.

Comparative Example An ionomer resin (Himilan P1702 manufactured by Mitsui Polychemical Co., Ltd., ion type Z _o , MI 14 g/10 min) was used as the polymer for the control layer, the same formulation as in the example, and an acrylic acid content of 8 weight as the adhesive. % EAA resin (EAA459 manufactured by Dow Chemical Company,
The above ionomer resin, compound and EAA resin were simultaneously multi-layer extruded in this order using a three-layer T-die using MI90g/10 minutes), and the ionomer resin layer, the aroma active substance-containing polymer layer and the EAA resin layer were sequentially formed.
It was made into a three-layer sheet consisting of a resin layer. A 20mm diameter extruder is used for extrusion of ionomer resin and EAA resin.
A 40 mm diameter extruder was used for extrusion of the aromatic active substance-containing polymer, and the extruder temperature was 130°C and the die temperature was 140°C. A 15 μm aluminum foil was thermocompression bonded to the EAA resin layer of the three-layer sheet thus obtained at a temperature of 120°C, and the control layer thickness was 100 μm and the fragrance-containing polymer layer thickness was 900 μm.
A polymeric laminate sheet with an adhesive layer thickness of 100 μm was obtained. Cut this sheet into 10cm x 10cm and heat it at 40℃ or
Weight loss due to fragrance release was measured in a constant temperature bath at 50°C. The results are shown in Figure 3. Compared to the laminated sheet according to the present invention, the release of fragrance at the cut-off period is extremely large, and the sustained release period of fragrance is extremely short. Further, although the laminated sheet of the present invention had a fragrance even after 40 days had passed, the laminated sheet of this comparative example had no fragrance after 25 days under the same exclusion conditions.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional polymer laminate sheet, Fig. 2 is a sectional view showing an example of a polymer laminate sheet according to the present invention, and Fig. 3 is a sectional view showing a polymer laminate sheet of the present invention and a comparative example. 1 is a graph showing the weight loss of active substance versus time; 1... Active substance-containing polymer layer, 3... Barrier layer, 5... Adhesive layer.

Claims (1)

[Claims] 1. A barrier layer consisting of a metal layer, a resin layer, or a laminate thereof having barrier properties against the active substance is adhered to two surfaces of a polymer layer containing a dissolved active substance. 1. A method for producing a polymer laminate sheet in which an active substance is sustainedly released only from the side surface of a polymer layer not covered with a barrier layer, which is bonded with an adhesive. 2. The method for producing a polymer laminate sheet according to claim 1, wherein the active substance is a chemical substance having pesticide activity or aromatic activity. 3. The polymer containing the active substance is polyvinyl chloride, ethylene with a vinyl acetate content of 12% by weight or more.
Vinyl acetate copolymer, acrylic acid content 15% by weight
The above ethylene-acrylic acid copolymers, styrene-butadiene rubber, ethylene-propylene rubber,
2. The method for producing a polymer laminate sheet according to claim 1, wherein the material is a styrene-isoprene-styrene block copolymer, natural rubber, or a mixture of two or more thereof. 4. The method for producing a polymer laminate sheet according to claim 1, wherein the barrier layer is made of aluminum foil or copper foil. 5. The method for producing a polymer laminate sheet according to claim 1, wherein the barrier layer is composed of a resin film and a vapor-deposited film of aluminum or copper. 6. The method for producing a polymer laminate sheet according to claim 1, wherein the barrier layer is a film of cellophane, ethylene-vinyl alcohol copolymer, polyethylene terephthalate, polyvinylidene chloride, or polyamide.