JPH0146481B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is a pest repellent material that can be installed in food stores, food storage pantries, etc. where pests such as flies, fleas, mites, and cockroaches can easily approach, or inside precision machinery or clean rooms, and is highly effective and long-lasting. This invention relates to pest repellent materials that are controlled to maintain their effectiveness. Conventionally, as a method of repelling pests from the human body,
A method is known in which drugs such as dimethyl phthalate, 2-ethyl-1,3-hexanediol, and indalone, which repel blood-sucking pests such as mosquitoes, lice, and mites, are applied alone or in combination to the skin. In addition, in recent years, new types of insect repellent materials have been developed in which insect repellents are impregnated into materials such as paper and cloth as insect repellent sheets, or the surfaces are coated as paint. However, as living standards have improved, there has been an increased demand for cleanliness.
There is a growing awareness of not only the intrusion of pests into living spaces, not just places where food is handled, but also the scattering of the bodies of killed pests. Furthermore, with the remarkable development of the electronics and medical industries, precision machines themselves and the spaces in which they are handled are required to have a high degree of cleanliness. The above-mentioned insecticidal and repellent materials often scatter corpses of pests, and are not suitable for these purposes. There is a strong demand for the development of a repellent material that is highly effective in keeping pests away, has a long-lasting effect, and has appropriately controlled sustained drug release. In order to make the repellent performance remarkable, in addition to the effectiveness of the drug, it is necessary to increase the concentration of the drug in the base material and gradually evaporate it into the external space. Products in which a repellent is mixed with paint and applied to a substrate are known, but there is a limit to the thickness of the paint film, and even when mixed at a high concentration, the total amount of the agent does not increase, which limits the repellent effect. Also, if the concentration is too high, the performance of the coating will deteriorate.Therefore, a method of impregnating a relatively thick base material such as cloth or paper with an appropriate concentration of the drug may be considered, but this method does not allow for long-term control of sustained release. It is something that cannot be done. Therefore, it contains an appropriate amount of the drug, and the ingredients that make up the base material are chemically and chemically compatible with the drug.
A substance with physical affinity and controlled sustained release is required. Furthermore, it is necessary that this repellent material be made into a molded body that can suitably follow the spaces and irregularities of the installation location. Conventionally, as a method to satisfy such conditions,
In some cases, chemicals such as repellents, insecticides, fungicides, and fragrances were mixed with general-purpose thermoplastic resins such as polyethylene, polypropylene, and polyvinyl chloride. Additionally, in order to increase the concentration, methods have been used in which these plastic fillers support these drugs. However, these thermoplastic resins generally have a relatively high melting point of 100° C. or higher, and in a method of kneading a drug in the molten state of the resin using thermoplasticity, the drug often decomposes or evaporates. In particular, even if there is a small amount of decomposition or transpiration, a large amount of it will accumulate during long-term continuous operation, which is impractical when considering the safety and efficiency of the manufacturing process. Generally, in order for a drug to evaporate from the surface of a substrate, the drug itself must have a high vapor pressure, and particularly effective drugs have high evaporation properties at room temperature. If these chemicals are kneaded into a plastic with a high melting point in an excessively large amount, the chemicals will decompose and bleed onto the surface. In addition, similar to the pest repellent of the present invention, those in which a thermoplastic elastomer is supported with fragrances, agricultural chemicals, insecticides, etc. are disclosed in JP-A-56-15377 and JP-A-48-88232. This is already known, and molding made by mixing insecticides with chlorinated polyethylene was published in the 1980s.
It is already known in Japanese Patent Publication No. 39522 and Japanese Patent Publication No. 49-34461. By the way, the former (Japanese Unexamined Patent Application Publications No. 115377/1982 and No. 88232/1983), which contains fragrances,
Thermoplastic elastomers used as carriers for agricultural chemicals or insecticides contain a large amount of rubbery polymer structures, so they have poor long-term shape retention, especially when used in pest repellents such as the present invention. However, there remains a problem with its long-term, stable efficacy. In addition, while the chlorinated polyethylene used in the latter (Japanese Patent Publication No. 55-39522, Japanese Patent Publication No. 49-34461) has excellent moldability and shape retention, the chlorinated polyethylene When polyethylene is used as a pest repellent, its effectiveness cannot be controlled. As a result of conducting research and development based on the ideas described above, the present invention found that chlorinated polyethylene has an extremely high affinity for a repellent made of diethyltoluamide, which is in a liquid state at room temperature, and that it is possible to increase its content. In addition, the chlorinated polyethylene is in a powder form and can uniformly support the repellent, and is extremely suitable for thermoforming into granules with the repellent supported thereon. On the other hand, ethylene-propylene polymer, styrene-butadiene copolymer, blend of soft PVC and PVC nitrile rubber, PVC-urethane copolymer, polyurethane system, polyester system, ethylene-propylene rubber, ethylene-ethyl Acrylate copolymer, ethylene vinyl acetate copolymer,
A thermoplastic elastomer made of at least one type of syndiotactic 1,2-polybutadiene has both a binding force and a non-binding force with respect to the repellent, as will be explained in detail later. It has been discovered that the evaporation, or effectiveness, of the repellent can be controlled by mixing it into chlorinated polyethylene carrying the repellent. Therefore, in the present invention, ethylene-propylene polymer, styrene-butadiene copolymer, blend of soft polyvinyl chloride and polyvinyl chloride nitrile rubber, polyvinyl chloride-urethane copolymer, polyurethane-based, polyester-based, ethylene- A thermoplastic elastomer made of at least one of propylene rubber, ethylene-ethyl acrylate copolymer, ethylene vinyl acetate copolymer, and syndiotactic 1-2-polybutadiene, a repellent made of diethyltoluamide, and chlorinated By mixing it with polyethylene and molding it, they were able to create an insect repellent that can be manufactured safely and maintains a controlled repellent effect over a long period of time. Using diethyltoluamide, the repellent is mixed with chlorinated polyethylene to form granules, and this mixture is kneaded with a thermoplastic elastomer and thermoformed. The repellent may be an insecticide or an insecticide depending on the purpose.
Insect repellents, rodenticides, rodent repellents, bird repellents, etc. can be used in combination. Further, as the thermoplastic elastomer, polyolefin type (ethylene-propylene polymer),
Styrene-butadiene-based (styrene-butadiene copolymer), PVC-based (soft PVC, vinyl chloride nitrile rubber blend, PVC-urethane copolymer), polyurethane-based, polyester-based, ethylene-propylene rubber, ethylene-ethyl acrylate copolymer , ethylene-vinyl acetate copolymer, and syndiotactic 1,2-polybutadiene, etc., and those having a melting point of 100° C. or lower are preferably used. The degree of affinity of the thermoplastic elastomer with the repellent is determined by the chemical properties resulting from its molecular structure (particularly the side chains of the polymer and copolymer components). Also, the type of elastomer (block copolymer,
Graft copolymers, random copolymers, homopolymers, blends, chemically modified products, etc.) may have various binding moieties (frozen phase, hydrogen bonding, crystalline phase ionic crosslinking) to the rubber phase of the unbound component. etc.) exist,
This physical structure is thought to control drug retention and release in various ways. In general, the rubber phase is a drug-retaining component because the molecules are in a random state, and the constrained part forms a densely arranged aggregate of molecules, so it is thought to act as a component that controls the release of the drug. It is also believed that the interface between the polymers created by the polymer blend forms fine passages through which the drug migrates from the inside of the molded article to the surface. It is thought that the sustained release of the drug is well controlled by a combination of the above factors. By the way, chlorinated polyethylene has a chlorine content of 30 to 45 wt%, and is structurally considered to be a terpolymer of ethylene, vinyl chloride, and 1,2-dichloroethylene. Correspondingly, it is formed from a crystalline phase and a rubbery phase. The constrained portion, which is a crystalline phase, is a pseudo-lamellar hard phase. Chemically, it has the following structure showing intermediate properties between polyethylene and polyvinyl chloride. When this powdered chlorinated polyethylene is mixed with the repellent described above, the latter is very well absorbed by the former. When the two are mixed, if the crystallinity of the chlorinated polyethylene is relatively high at 10 to 25%, the repellent will be difficult to absorb into the chlorinated polyethylene at the initial stage of mixing, but over time the repellent will gradually absorb into the chlorinated polyethylene. It is absorbed and the whole becomes a block mass. On the other hand, when the degree of crystallinity is relatively low, up to about 5%, the repellent is absorbed quickly and the absorbed powder becomes lumpy and does not bleed later, and the whole remains powdery or granular. Therefore, it is preferable that the chlorinated polyethylene suitable for the present invention has a small amount of crystalline phase, which is a constrained part, and, in other words, a large amount of rubber phase. On the other hand, among the plastic elastomer components, polyolefins, styrene-butadiene, 1,2-polybutadiene, etc., which have relatively low polarity, have almost no affinity with the repellent consisting of diethyltoluamide, and therefore do not have much affinity for the rubber phase or the interface of the polymer blend. Although they physically retain some repellent, the degree of crystalline phase essentially affects the release of the repellent. Ethylene-vinyl acetate copolymers, vinyl chloride polyurethane systems, etc. containing somewhat polar groups have intermediate effects. For this reason, the elastomer blend components can be selected freely taking into account the degree of repellent release. Generally, repellents are most effective at 1% by weight or more.
Practically speaking, considering the sustainability of effects and cost, 5~
It is preferably about 20%, but may contain 40 to 50% depending on the use. The amount of chlorinated polyethylene increases or decreases depending on the amount of repellent, but when the latter is 5 to 10%, it is appropriate to be 20 to 40% compared to the elastomer, and when the latter is 10 to 30%, it is appropriate to be about 30 to 70%. The mixture of the repellent, chlorinated polyethylene, and thermoplastic elastomer is processed into sheets, nets, rods, and other molded bodies using a general thermoforming machine for elastomers. Next, the present invention will be explained by giving specific examples. Example Chlorinated polyethylene [Product name: Daisolak H
-135, Osaka Soda Co., Ltd.] 300 parts with N/N as a repellent
-Diethyl-m-toluamide was mixed with the polymer blend using a vertical granulator at a blending ratio as shown in the following table to form suitable granules. Next, 300 parts of 1,2-polybutadiene [product name: JSR RB-810 Japan Synthetic Rubber Co., Ltd.], ethylene vinyl acetate copolymer [product name: Ultracene]
634 Toyo Soda Co., Ltd.] 200 parts, mixed with 300 parts of ethylene-propylene polymer [trade name: Tafmer P-0280 Mitsui Petrochemical Industries, Ltd.] mixed pellets, and heated to 95 to 100°C using an extruder. A 2 mm soft sheet-like repellent material was produced by extrusion. The cockroach repellency rate and the residual rate of the repellent over time of this sheet-like repellent material were as shown in the following table.

[Table] The repellency rates in the table were obtained using the following experimental method. Bat shown in the figure (1m x 1m x depth 80cm) (A)
A partition wall (B) is installed in the center of the partition wall (B), and a width
A passage (b) of 10 cm x 5 cm in height was established, a 1 m x 80 cm sheet containing repellent was installed in T, and a 1 m x 80 cm sheet containing no repellent was installed in C. 30 cockroaches were left in a room approximately in the center of the partition wall (B), and the percentage of cockroaches present in room C after 2 hours is expressed as a percentage.

[Brief explanation of drawings]

The drawing is an explanatory diagram of the experimental method of repellency rate.

Claims (1)

[Claims] 1 Ethylene-propylene polymer, styrene-
Butadiene copolymer, blend of soft polyvinyl chloride and polyvinyl chloride nitrile rubber, polyvinyl chloride-urethane copolymer, polyurethane type, polyester type, ethylene-propylene rubber, ethylene-ethyl acrylate copolymer, ethylene acetic acid It is characterized by being molded by mixing a thermoplastic elastomer made of at least one of a vinyl copolymer and syndiotactic 1,2-polybutadiene, a repellent made of diethyltoluamide, and chlorinated polyethylene. Pest repellent.