JPS6117266B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polymer laminate sheet, and more particularly to a polymer laminate sheet containing an active substance that has physical and/or chemical activity and acts as a good solvent for polymers, especially adhesives and pressure-sensitive adhesives. . Made from synthetic resins, synthetic rubbers, etc. that contain non-volatile or volatile active substances that have physical and/or chemical activities such as pesticide activity, repellent activity, and aromatic activity, and that allow the active substances to be released in a sustained manner. Various polymer laminated sheets are known, and such sheets (including tapes) often have a pressure-sensitive adhesive layer or an adhesive layer on the back side and can be attached to a desired surface. It is used as However, many active substances act as good solvents for polymers, and in these cases, if a polymeric adhesive is applied directly to the polymer layer containing the active substance, the active substance may The adhesive easily dissolves, so that the sheet peels off from the surface to which it is applied within a short period of time, and even the active substance may contaminate the surface to which it is applied. Therefore, when providing an adhesive layer on the back side of a polymer layer containing an active substance that acts as a good solvent for adhesives or pressure-sensitive adhesives, it is necessary to provide a barrier property to the active substance on the back side of the polymer layer. It is desirable to laminate a metal layer or a resin film having the above properties as a barrier layer, and provide an adhesive layer on this barrier layer. However, as mentioned above, when the active substance is a good solvent for the adhesive, the polymer layer containing the active substance and the barrier layer cannot be strongly bonded together with conventionally commonly used adhesives. It was not possible to obtain a bonded laminated sheet, and there was a problem in that the polymer layer was easily peeled off from the barrier layer after several days to a month had passed. The present invention has been made in order to solve the above problems, and the present invention has been made in such a way that a polymer layer containing an active substance that acts as a good solvent for polymers, particularly adhesives and pressure-sensitive adhesives, and a barrier layer are strong. The object of the present invention is to provide a polymeric laminate sheet that is adhered to a laminate sheet. The polymer laminate sheet of the present invention comprises (a) a polymer layer containing an active substance that acts as a good solvent for the polymer, and (b) a metal layer or a metal layer and a resin film, the active substance being The polymer layer and the metal layer of the barrier layer are bonded to each other with an adhesive made of an ethylene-acrylic acid copolymer resin containing 5 to 15% by weight of acrylic acid. It is characterized by being glued. In the present invention, an active substance that acts as a good solvent for a polymer is a polymer that is physically and/or chemically active and that forms an adhesive or a pressure-sensitive adhesive used in a laminated sheet. Activities include chemical activities such as insecticidal, sterilizing, antifungal, repellent, attracting, etc., physical activities such as fragrance, etc.
Examples include, but are not limited to, chemical activity, electrical conductivity, and physical activity such as antistatic property. Specific examples of active substances include 2,2-dichlorovinyl phosphate (DDVP), sumithion and pyrethroid insecticides, fungicides such as p-chloro-m-xylenol, mosquito, tick, and diethyltoluamide. Cockroach repellents, pheromones, attractants such as methyl eugenol, limonene, benzyl alcohol, esters derived from hydrocarbons having 6 to 16 carbon atoms, ethers, aldehydes and other fragrance substances may be mentioned. In the present invention, the polymer containing the active substance is
Synthetic resins, natural rubbers, synthetic rubbers, or mixtures thereof, which contain the active substance dissolved at a temperature of 15°C at a concentration of 5% by weight or more, preferably 10% by weight or more, are preferable, and various types may be used depending on the type of active substance. Specifically, polyvinyl chloride, ethylene-vinyl acetate copolymer with a vinyl acetate content of 12% by weight or more, ethylene-acrylic acid copolymer with an acrylic acid content of 15% by weight or more, styrene- Mention may be made of butadiene rubber, natural rubber, thermoplastic urethane elastomer, and mixtures of two or more thereof. 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. When 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, when the content of the active substance is too high. This is because it becomes difficult to form into a sheet. The metal layer having barrier properties is not particularly limited as long as it has barrier properties against the active substance used, but aluminum foil and copper foil are usually used. The thickness of these metal foils is sufficient to provide barrier properties to the active substance, typically 5.
~50μ. Further, the barrier layer may be a laminate in which a metal vapor-deposited film of aluminum, copper, etc. is formed on a resin film that has barrier properties against active substances. As the resin film, polyethylene, polypropylene, polyethylene terephthalate, polyamide, ethylene-vinyl alcohol copolymer, etc. are used, and polyethylene terephthalate, polyamide, and ethylene-vinyl alcohol copolymer are preferably used. The barrier layer may of course be a laminate of aluminum foil or copper foil and the above resin film. In the present invention, when the barrier layer consists only of a metal layer, the metal layer is adhered to the polymer layer, and when the barrier layer consists of a metal layer and a resin film, the metal layer is adhered to the polymer layer. The adhesive used in the present invention is specified as an ethylene-acrylic acid copolymer resin (hereinafter referred to as EAA resin) having an acrylic acid content in the range of 5 to 15% by weight. It is surprising that only EAA resins with a specific range of acrylic acid content are able to strongly bond both layers when bonding a polymer layer containing an active substance that acts as a good solvent for the polymer and a metal layer. That's true. When a specific EAA resin is used in this manner, the adhesion between the metal layer and the polymer layer is extremely strong, and if an attempt is made to peel off the metal layer, the polymer laminate sheet will be destroyed. On the other hand, when an EAA resin with an acrylic acid content outside the above range is used as an adhesive, the resulting laminate sheet is such that the metal layer peels off from the polymer layer with almost no force required after 2 to 3 months. . The EAA resin used in the present invention preferably has a melt index of 5 to 150 g/10
minutes, particularly preferably in the range of 8 to 40 g/10 minutes. The polymer laminate sheet of the present invention can be produced by, for example, laminating an EAA resin on a metal layer of a barrier layer.
A polymer layer containing an active substance is bonded by thermocompression onto an EAA resin layer, and a polymer containing an active substance and an EAA resin are formed into a two-layer sheet by multilayer extrusion, and the EAA resin of this sheet is It is obtained by thermocompression bonding the metal layer of the barrier layer to the layer facing each other. The thickness of the EAA resin layer is not particularly limited, but is usually 10-200μ. As explained below, a laminate sheet having a control layer on an active substance-containing polymer layer can also be produced, for example, by coextruding the polymer for the control layer, the active substance-containing polymer, and the EAA resin in this order. A three-layer sheet, and this sheet
It can be obtained by thermocompression bonding a metal layer of a barrier layer to an EAA resin layer. The active substance in the polymer layer may migrate to the polymer layer surface of the laminate sheet to which the polymer layer and metal layer are bonded, providing a substantially constant effective concentration at the surface, or may be substantially removed from the polymer surface. However, in the present invention, in order to more stably control the effective concentration of the active substance on the surface of the laminated sheet or the rate of vaporization from the surface of the laminated sheet, the active substance is added to the active substance-containing polymer layer. A control layer made of another polymer may also be laminated. As the polymer for this control layer, a polymer is selected whose saturation solubility is relatively smaller than the active substance content of the active substance-containing polymer layer, e.g. is 10% by weight, the control layer uses a polymer whose saturated solubility of the active substance is 5% by weight. Polymers for such control layers often include, for example, polyethylene, polypropylene,
Ethylene-vinyl acetate copolymer with a vinyl acetate content of 8% by weight or less, ethylene-acrylic acid copolymer with an acrylic acid content of 15% by weight or less, ethylene-vinyl acetate copolymer with a vinyl acetate content of 8 to 45% by weight Ethylene-vinyl acetate with a combination of more than 50% saponified
Examples include vinyl alcohol copolymers and ionomer resins. When the polymer laminate sheet has a control layer in this way, the active substance contained in the polymer layer is once dissolved in the control layer and transferred to form a constant effective concentration on the surface of the control layer, or The active substance vaporizes at a constant rate from the surface of the laminated sheet, but as mentioned above, since the saturated dissolved amount of the active substance in the control layer is small compared to the active substance content in the polymer layer, the activity on the surface of the laminated sheet decreases. The effective concentration of the substance or rate of vaporization from the surface can be kept more constant and over a longer period of time. The control layer can also be laminated onto the polymer layer by methods such as thermocompression bonding, adhesive bonding, multilayer extrusion, etc., but preferably the polymer forming the control layer and the polymer containing the active substance are combined with the polymer layer forming the control layer and the polymer containing the active substance. EAA resin is extruded in three layers, and a barrier layer is thermocompression bonded to the thus obtained three-layer sheet to obtain a polymer laminated sheet of the present invention. Although the thickness of the control layer is not particularly limited, it is usually about 5 to 200 microns. In addition, in the present invention, in order to control the effective concentration of the active substance on the surface of the polymer laminate sheet or the vaporization rate of the active substance from the surface, the control layer comprises a polymer layer containing the active substance within a compatible range. On the other hand, without providing a control layer, the polymer constituting the polymer layer may contain a polymer for the control layer. The polymeric laminated sheet is provided with an adhesive layer on the exposed surface of the barrier layer in order to adhere to a desired surface such as furniture, floors, walls, etc. What is the exposed surface here?
When the barrier layer is made of a metal layer, it refers to its exposed surface, and when the barrier layer is a laminate of a metal layer and a resin film, it refers to the exposed surface of the resin film. As the adhesive, conventionally known adhesives are used as appropriate, such as acrylic acid-acrylic acid ester copolymer resin adhesive, ethylene-vinyl acetate copolymer resin adhesive, natural rubber adhesive, A synthetic rubber adhesive or the like is used. As explained above, the polymer laminate sheet of the present invention has a polymer layer containing an active substance that acts as a good solvent particularly for adhesives and pressure-sensitive adhesive polymers, and a barrier layer for the active substance. , the metal layer of the barrier layer is specifically and firmly bonded by the EAA resin with a specific acrylic acid content as the adhesive surface, and the adhesive of the barrier layer is shielded from the active substance, so the polymeric laminated sheet is stably adhered to the surface to which it is adhered over a long period of time, and the active substance does not contaminate the surface to which it is adhered. 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 Ionomer resin (Himilan 1702 manufactured by Mitsui Polychemical Co., Ltd., ion type) as a polymer for the control layer
Zn, MI14g/10 min) or ethylene-vinyl alcohol copolymer (Sumilink manufactured by Sumitomo Chemical Co., Ltd.)
DR-55-P, MI120g/10min), and EAA resin with acrylic acid content of 8% by weight as an adhesive (EAA459 manufactured by Dow Chemical Company, MI9.0g/10min).
These are simultaneously extruded using a three-layer T-die together with any of the following formulations containing aroma-active substances to form a three-layer sheet consisting of a control layer, a polymer layer containing an aroma-active substance, and an EAA resin layer in this order. did.
A 20 mm diameter extruder was used to extrude the control layer polymer and the EAA resin, and a 40 mm diameter extruder was used to extrude the fragrance active substance formulation, and the extruder temperature was 130 °C and the die temperature was 140 °C. . One of the following metal layers was added to the EAA resin layer of the three-layer sheet obtained in this way at 120°C.
It was thermocompressed at a temperature of . Compound (1) Fragrance (Lemon fragrance #673-858 manufactured by Ogawa Fragrance Co., Ltd.)
100 parts of the mixture and 400 parts of ethylene-vinyl acetate copolymer (P2807 manufactured by Mitsui Polychemical Co., Ltd.) were kneaded with a hot roll, pressed, and then cut into ribbons of approximately 2 mm x 5 mm x 500 mm. Blend (2) 100 parts of the same fragrance as Blend (1), 100 parts of dioctyl phthalate and polyvinyl chloride (diamond).
Mix well 300 parts of PVC74 manufactured by Shamrock Co., Ltd.
After being stored in a constant temperature bath at 50°C for 24 hours, it was made into granules with a diameter of about 3 mm. Metal layer (1) 15μ thick aluminum foil Metal layer (2) 6μ thick aluminum foil and 25μ thick
Laminated metal layer with polyethylene terephthalate film (3) Electrolytic copper foil metal layer 24μ thick (4) Polyethylene terephthalate film 25μ thick with aluminum vapor-deposited on one side to a thickness of 80Å Polymerized laminate thus obtained Sheets 1 to 6 have a control layer of 100 to 150 μm in thickness and a fragrance-containing layer of 600 to 800 μm in thickness.
μ, the adhesive layer was 100 to 150 μ. 20 each sheet
After cutting into pieces of mm x 100 mm and storing them in a constant temperature bath at 27°C for 3 months, the adhesive strength between the fragrance-containing polymer layer and the metal layer was examined, and the results are shown in the table below.

[Table] Comparative example Adhesive with acrylic acid content of 20% by weight
EAA resin (EAA XO− manufactured by Dow Chemical Company)
Laminate sheet 7 was obtained in exactly the same manner as laminate sheet 4 except that 2375.33, MI 300 g/10 min) was used, and acrylic acid content of 3.5% by weight was used as an adhesive.
EAA resin (EAA435, MI11 manufactured by Dow Chemical Company)
A laminate sheet 8 was obtained in exactly the same manner as laminate sheet 4 except that 1 g/10 min) was used. The adhesive strength evaluated in the same manner as in the examples is shown in the table above.

Claims (1)

[Scope of Claims] 1. Consisting of (a) a polymer layer containing an active substance that acts as a good solvent for the polymer, and (b) a metal layer or a metal layer and a resin film, the polymer layer and the metal layer of the barrier layer are bonded together with an adhesive made of an ethylene-acrylic acid copolymer resin containing 5 to 15% by weight of acrylic acid. A polymer laminated sheet characterized by: 2. The polymeric 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 polymer laminate sheet according to claim 1, characterized in that it is the above-mentioned ethylene-acrylic acid copolymer, styrene-butadiene rubber, natural rubber, or a mixture of two or more thereof. 4. The polymer laminate sheet according to claim 1, wherein the barrier layer is made of aluminum foil or copper foil. 5. The polymer laminate sheet according to claim 1, wherein the barrier layer comprises a resin film and a vapor-deposited film of aluminum or copper.