insect net

Abstract

To provide an insect proof net with good air permeability, which has durability of excellent pest repellency and pest repellency effect, and which has a constant mesh size and causes no displacement, thereby preventing insect pest from entering an agricultural facility, such as a greenhouse.SOLUTION: The above problem can be solved by an insect proof net in which a thermal adhesive irregular fiber having an optimized shape irregularity and having an insect repellent mixed therein is knitted by setting a mesh size to a predetermined range.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an insect repellent net, and more particularly to an insect repellent net having excellent insect pest repellency. [Background technology]

[0002] Protecting crops from pests has been a challenge in agricultural production since ancient times. Methods for dealing with pest damage include killing insects with pesticides or natural enemies, preventing pest invasions with covering materials, eliminating pests through repellent effects, and exterminating them through attracting them. The widespread use of pesticides has dramatically reduced pest damage to crops, thereby significantly increasing yields. However, this has also caused problems, such as chemical burns for agricultural workers, pesticide residue harm for consumers, and ecosystem destruction for the environment. For this reason, efforts have been made to develop pesticides that are harmless or even harmless to humans and the environment. However, the use of these pesticides and other chemicals requires procedures such as spraying and fumigation, which place a significant burden on agricultural producers. Furthermore, even with chemicals that are now considered harmless, the long-term effects have yet to be fully elucidated.

[0003] Furthermore, with growing health consciousness and a consumer trend toward organically grown crops that are pesticide-free or low in pesticides, there is a demand for insect control methods that do not rely solely on traditional pesticide-based pesticides. One method of pest control that does not require pesticides is to use covering materials. These covering materials are used in greenhouses and tunnels, so-called protected horticulture, and by covering the greenhouses and tunnels, pests are prevented from entering the greenhouses and tunnels. Agricultural films, cheesecloth, nets, and nonwoven fabrics are widely used as covering materials.

[0004] Of these, agricultural film is a covering material primarily intended for insulation and rain protection, and is not breathable. During hot periods when pests are most active, facilities become humid, necessitating ventilation, which can open up the covering and allow pests to invade. Therefore, it is not recommended to use it alone as an insect control measure, except during cold periods. Cheesecloth and nonwoven fabric are covering materials intended for light blocking and heat retention, but they lack strength and are prone to tearing, allowing pests to enter through the torn gaps and damage crops, so they are also not recommended for use as an insect control measure. Netting, which is breathable and uses strong fibers, is preferred as a covering material for insect prevention, and netting woven from monofilament made of thermoplastic resin is particularly used as insect netting.

[0005] The performance of insect netting is basically determined by the size of the gaps created by the fibers that make up the netting. The size of these gaps is usually expressed as the "mesh size," which is the distance between adjacent fibers.

[0006] In the case of conventional insect netting, the mesh size is often not fixed, and the fibers move during wind, rain, and handling, causing the mesh size to change, resulting in "mesh gaps," which often allow pests to enter through the widened mesh. Later, a method was developed to heat-seal the intersections of the fibers that make up the net as a way to prevent mesh gaps in insect netting and maintain a constant mesh size, but it was difficult to completely prevent pests from entering through mesh size alone.

[0007] To prevent the invasion of such pests, fibers containing insect repellents are widely used. For example, one document has disclosed an insect repellent fiber having a core-sheath structure, in which the crystallinity of the resin constituting the sheath is equal to or lower than that of the resin constituting the core, and in which an insect repellent is kneaded into the core. It has been shown that insect repellent fibers with irregular shapes such as circular, flat, triangular, hollow, and star-shaped can be used, and that circular shapes are preferable from the viewpoints of abrasion resistance, positional stability, and smoothness, but no suggestion has been made about the influence of the shape or irregularity of the fiber on the effectiveness of the insect repellent (Patent Document 1). Furthermore, an agricultural insect control netting has been proposed that incorporates the insecticide etofenprox, is for use against thrips or whiteflies, has a mesh size of 0.4 mm or more and 0.8 mm or less, and is a woven fabric made of monofilaments that incorporate etofenprox (Patent Document 2). Alternatively, a core-sheath multifilament has been proposed in which the single fibers constituting the multifilament have a core and a sheath formed on the outside thereof, the core contains a pyrethroid compound as an insect repellent, the content of the pyrethroid compound being 0.1 to 3 mass% relative to 100 mass% of the core-sheath multifilament, and the single fiber fineness is 1 to 7 dtex (Patent Document 3). These insect nets are simply made of fibers containing insecticides, and are insufficient in terms of insect repellency.

[0008] On the other hand, an insect repellent net has been disclosed in which the shape of the fiber itself is controlled by using thermally adhesive fibers that make up the threads as irregularly shaped fibers, so that the insect repellent net itself generates various reflected light rays and stripes, thereby exhibiting insect pest repellency (Patent Document 4). However, this technology does not anticipate the introduction of insect repellents, does not suggest the influence of the shape or degree of irregularity of the fibers on the effectiveness of the insect repellent, and is insufficient in terms of pest repellency. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] International Publication No. 2016 / 143809 [Patent Document 2] International Publication No. 2019 / 139161 [Patent Document 3] Japanese Patent Application Publication No. 2020-63537 [Patent Document 4] Japanese Patent Application Laid-Open No. 2000-217497 Summary of the Invention [Problem to be solved by the invention]

[0010] To provide an insect-proof netting having excellent pest repellency and long-lasting pest repellency, a uniform mesh size that does not cause misalignment, which suppresses the invasion of pests into agricultural facilities such as greenhouses, and which has good breathability. [Means for solving the problem]

[0011] As a result of intensive research conducted by the inventors to solve the problems of the above-mentioned conventional technology, the inventors discovered that the above-mentioned problems can be solved by using, as the fiber constituting the insect net, an irregular fiber whose irregularity value is optimized from the perspective of pest repellency, and by using, as the irregular fiber, a thermally bondable fiber into which an insect repellent has been kneaded, and by using the thermally bondable fiber to knit and weave the insect net with a mesh size set within a specific range, thereby completing the present invention.

[0012] That is, the present invention has the following configuration. [1] An insect-proof netting in which the intersections of fibers are thermally bonded, the fibers constituting the insect-proof netting are thermally bondable irregular fibers having a degree of irregularity in the range of 1.10 to 2.20 and containing an insect repellent mixed therein, and the mesh size of the insect-proof netting is in the range of 0.8 to 3.0 mm. [2] The insect netting according to [1], wherein the thermally adhesive non-circular fiber has a fineness in the range of 100 to 5000 dtex. [3] The insect netting according to [1] or [2], wherein the thermally adhesive non-circular fiber has a sheath-core structure, and the ratio (V1 / V2) of the core volume V1 to the sheath volume V2 is in the range of 50 / 50 to 90 / 10. [4] The insect repellent net according to any one of [1] to [3], wherein the insect repellent is a pyrethroid compound. [5] The insect repellent net according to any one of [1] to [4], wherein the insect repellent is a microencapsulated insect repellent. [6] The insect repellent net according to any one of [1] to [5], wherein the proportion of the thermally adhesive non-circular fibers is 20% by mass or more of the total fiber amount. [Effects of the Invention]

[0013] By using thermally bondable irregular fibers having a degree of irregularity in the range of 1.10 to 2.20 and kneaded with an insecticide as the fibers constituting the insect repellent net of the present invention, it is possible to appropriately control the phenomenon of the insect repellent seeping out from the interior of the fiber (bleed-out) and the diffusion of the insect repellent from the fiber surface. The insect repellent net of the present invention exhibits excellent pest repellency and sustained pest repellency by knitting or weaving a fabric with a mesh size of 0.8 to 3.0 mm using the thermally bondable irregular fibers. By thermally bonding the intersections of the thermally bondable fibers, it is possible to provide an insect repellent net that is less likely to misalign and is highly effective in preventing the intrusion of pests blown by wind, etc. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 10 is a conceptual diagram for explaining how to determine the degree of irregularity. [Figure 2] FIG. 1 is a schematic diagram of the device used to test pest repellency. [Figure 3] 1 is a microscope image of the thermal adhesive non-circular fiber 1. [Figure 4] 1 is a microscope image of the thermal adhesive non-circular fiber 2. [Figure 5] 1 is a microscope image of a thermal adhesive fiber 3. [Figure 6] 1 is a microscope image of thermal adhesive fiber 4. DETAILED DESCRIPTION OF THE INVENTION

[0015] An embodiment of the present invention is described below. The fibers constituting the insect repellent netting of the present invention are thermally bondable irregular fibers having a degree of irregularity in the range of 1.10 to 2.20 and kneaded with an insect repellent. The insect repellent netting of the present invention is produced by forming the thermally bondable irregular fibers into a knitted or woven fabric having a mesh size in the range of 0.8 to 3.0 mm and then heat-treating the knitted or woven fabric to bond the intersections of the fibers. The thermally bondable irregular fibers have a fineness in the range of 100 to 5000 dtex and have a sheath-core structure in which the ratio (V1 / V2) of the core volume V1 to the sheath volume V2 is in the range of 50 / 50 to 90 / 10. The insect repellent of the present invention may be a pyrethroid compound or a microencapsulated insect repellent. Furthermore, at least 20% of the total fiber content of the insect repellent may be the thermally adhesive non-circular fiber.

[0016] In the insect net of the present invention, the thermally adhesive non-circular fibers constituting the insect net have a degree of irregularity in the range of 1.10 to 2.20, preferably in the range of 1.15 to 1.50. The degree of irregularity of a fiber is the value obtained by dividing the circumference of the cross section by the circumference of a circle with the same area as the cross section. By setting the degree of irregularity to 1.10 or more, the cross section of the fiber becomes more irregular than a circle, increasing the surface area of ​​the fiber and thereby increasing the effectiveness of the insect repellent kneaded into it. Furthermore, the glitter caused by reflected light becomes stronger, and these synergistic effects can be expected to provide sufficient insect repellency. Furthermore, by setting the degree of irregularity to 2.20 or less, the length of the protruding parts does not become too large, preventing a decrease in fiber strength. Furthermore, there is no significant decrease in the knitting and weaving properties of the net. The irregular shape is not particularly limited, and various shapes such as star, H, M, N, V, W, X, Y, and * (asterisk) shapes, as well as oval, flat, triangular, and hollow shapes can be used. However, considering spinning stability, insect repellent effect, and the glittering effect of reflected light, star, H, X, Y, and * (asterisk) shapes are preferred. Furthermore, the fiber may have a hollow portion, or may be a composite fiber such as an islands-in-the-sea type. When the fiber has a hollow portion, it can have a multilayer structure.

[0017] In the insect net of the present invention, the fibers constituting the insect net have a fineness in the range of 100 to 5000 dtex, preferably in the range of 150 to 2800 dtex. The relatively finer the fibers, the more fibers can be used to make up the insect net, which increases the total fiber surface area and improves insect control performance. A fineness of 100 dtex or more reduces the strength of the insect net and the risk of tearing. A fineness of 5000 dtex or less prevents the weight of the insect net from becoming too large, making it easy to transport and preventing excessive loads from being applied to the deployed area, thereby reducing the risk of damage to facilities such as greenhouses.

[0018] The thermally adhesive non-circular fibers constituting the insect net of the present invention may be regular monofilaments made of a single component resin, composite monofilaments made of multiple resins, or multifilaments made of a single component resin or multiple resins. In particular, thermally adhesive composite monofilaments are preferably used in order to form intersections with sufficient adhesive strength when the fibers are thermally bonded.

[0019] The thermally bondable non-circular fiber of the present invention is preferably a thermally bondable fiber composed of two or more resins, each of which comprises a low-melting point resin and a high-melting point resin with a melting point difference of at least 10°C, and at least a portion of the fiber surface being formed by the continuous low-melting point resin. The thermally bondable non-circular fiber may have any structure, such as a sheath-core, side-by-side, or sea-island structure, but considering the special shape of the non-circular fiber, a sheath-core / side-by-side structure is preferred. Among these, thermally bondable non-circular fibers with a sheath-core structure are preferred because they have good and consistent thermal adhesion. In this case, it is not necessary for only the sheath portion to be deformed; both the sheath and core may be deformed.

[0020] The ratio (V1 / V2) of the core volume V1 to the sheath volume V2 of the sheath-core structure is preferably in the range of 50 / 50 to 90 / 10, more preferably 55 / 45 to 80 / 20, and even more preferably 60 / 40 to 75 / 25. When the ratio (V1 / V2) is 50 / 50 or more, it tends to be a value suitable for exhibiting sufficient insect repellent performance.When the ratio (V1 / V2) is 90 / 10 or less, the rapid action of the insect repellent performance is even more excellent.

[0021] Examples of the low-melting point resin and high-melting point resin that constitute the thermally adhesive non-circular fibers include thermoplastic resins such as high-density polyethylene, low-density polyethylene, linear low-density polyethylene, propylene copolymer, polypropylene, polyethylene terephthalate, and polyamide, with polyolefin resins such as polyethylene and polypropylene being particularly preferred.

[0022] Examples of combinations of the low-melting point resin and the high-melting point resin, when expressed as low-melting point resin / high-melting point resin, include high-density polyethylene / polypropylene, linear low-density polyethylene / polypropylene, low-density polyethylene / polypropylene, binary or terpolymer of propylene and other α-olefin / polypropylene, linear low-density polyethylene / high-density polyethylene, low-density polyethylene / high-density polyethylene, various polyethylenes / polyethylene terephthalate, polypropylene / polyethylene terephthalate, binary or terpolymer of propylene and other α-olefin / polyethylene terephthalate, low-melting point thermoplastic polyester / polyethylene terephthalate, various polyethylenes / nylon 6, polypropylene / nylon 6, binary or terpolymer of propylene and other α-olefin / nylon 6, nylon 6 / nylon 66, nylon 6 / thermoplastic polyester, and the like.

[0023] Among these, combinations of polyolefins or combinations of polyolefins and polyesters are preferred, and specific examples thereof include high-density polyethylene / polypropylene, ethylene-propylene-butene-1 terpolymer / polypropylene, ethylene-propylene binary copolymer / polypropylene, ethylene-propylene-butene-1 terpolymer / polyethylene terephthalate, high-density polyethylene / polyethylene terephthalate, etc. Furthermore, among these, combinations of polyolefins, such as high-density polyethylene / polypropylene, ethylene-propylene-butene-1 terpolymer / polypropylene, and ethylene-propylene binary copolymer / polypropylene, are particularly preferred from the standpoint of chemical resistance.

[0024] In the combination of the two-component resins, a low-melting point resin and a high-melting point resin, it is desirable to select two-component resins with a large difference in refractive index in order to emphasize the glittering effect of effective reflected light and obtain an excellent pest repellent effect. The thermally adhesive non-circular fiber may contain stabilizers, flame retardants, antibacterial agents, etc., within the scope of the present invention, as long as the effects of the present invention are not impaired. A colorant may also be added. The addition of a colorant can be expected to control the light blocking rate and heat retention, as well as to enhance the repellent effect against insects and birds.

[0025] In the insect repellent net of the present invention, the thermally adhesive non-circular fibers constituting the insect repellent net are kneaded with an insect repellent to improve repellency. In particular, when thermally adhesive non-circular fibers having a sheath-core structure are used, the insect repellent may be contained only in the sheath or only in the core, or may be contained in both the sheath and the core.

[0026] In the insect repellent net of the present invention, insect repellents that may be added to the thermally adhesive non-circular fiber include insect repellents intended for repellency, as well as agents that prevent the survival and reproduction of pest organisms, such as insecticides, rodenticides, fungicides, snailicides (murosicides), larvicides, and ovicides. In the present invention, it is preferable to use insect repellents that have the effect of quickly paralyzing or killing insects and have extremely low toxicity to mammals. These agents may be used alone or in combination with multiple agents that are expected to have the same efficacy. Furthermore, agents with different efficacy may be used in any combination depending on the application. Furthermore, known additives may be added to enhance the repellent effect.

[0027] A wide variety of known insect repellents can be used in the present invention, but pyrethroid compounds are preferred. Examples of pyrethroid compounds include acrinathrin, allethrin, d-allethrin, dd-allethrin, bifenthrin, cycloprothrin, cyfluthrin, beta-cyfluthrin, cyhalothrin, gamma-cyhalothrin, and lambda-cyhalothrin. lothrin, cypermethrin, alpha-cypermethrin, theta-cypermethrin, zeta-cypermethrin, cyphenothrin, deltamethrin, dimefluthrin, empenthrin, esfenvalerate e), etofenprox, fenpropathrin, fenvalerate, flucythrinate, flufenprox, flumethrin, fluvalinate, furamethrin, halfenprox, imiprothrin, metofluthrin tofluthrin), permethrin, fenothrin, d-fenothrin, prallethrin, profluthrin, pyrethrins, resmethrin, d-resmethrin, silafluofen, tau-fluvalinate, tefluthrin, telallethrin,Examples of pyrethroid compounds that can be particularly preferably used in the present invention include tetramethrin, d-tetramethrin, tralomethrin, transfluthrin, and natural pyrethrins. Examples of pyrethroid compounds that can be particularly preferably used in the present invention include at least one selected from the group consisting of permethrin, esfenvalerate, deltamethrin, alphacypermethrin, lambda-cyhalothrin, bifenthrin, and etofenprox.

[0028] In the thermally bondable non-circular fibers used in the insect net of the present invention, the content of the insect repellent is preferably 0.1 to 5.0% by mass relative to 100% by mass of the thermally bondable non-circular fibers, more preferably 0.2 to 4.0% by mass, and particularly preferably 0.3 to 3.0% by mass relative to 100% by mass of the thermally bondable non-circular fibers. When the content of the insect repellent is 0.1% by mass or more relative to 100% by mass of the thermally bondable non-circular fiber, excellent repellent performance is obtained and the durability of the insect repellent performance tends to be excellent. When the content of the insect repellent is 5.0% by mass or less relative to 100% by mass of the thermally bondable non-circular fiber, thermally bondable non-circular fiber can be obtained with stable spinnability.

[0029] Various insect-repellent fibers have been proposed that have insect-repellent properties, such as fibers in which an insect repellent is attached to the surface of the fiber after production. However, the amount of attached insect repellent decreases due to wind, rain, washing, etc., making it difficult to control the durability of the insect repellent performance. In contrast, in the thermally bondable non-circular fiber of the present invention, the insect repellent is distributed also inside the fiber, so the durability of the insect repellent performance can be easily controlled by adjusting the type and content of the insect repellent. Furthermore, in the present invention, by optimizing the surface area of ​​the fiber by using a non-circular fiber with a specific degree of irregularity, or by using a thermally bondable non-circular fiber with a sheath-core structure in which the physical properties of the sheath and core are different, it is possible to control the bleed-out of the insect repellent from inside the fiber and the diffusion of the insect repellent from the surface of the fiber, thereby achieving durable pest repellency.

[0030] The thermally adhesive non-circular fibers used in the insect net of the present invention can be produced by melt spinning. For example, when a thermally adhesive non-circular fiber with a sheath-core structure is used, a predetermined amount of insect repellent can be incorporated into the core by melt-kneading the resin that forms the core with the insect repellent during the spinning stage. Alternatively, the insect repellent can be kneaded into the resin that forms the core during melt-kneading. Kneading the insect repellent into the core can prevent the repellent performance from decreasing over time. As a result, the insect repellent performance can be made more durable and sustainable than when an insect repellent is attached to the surface of the fiber after production.

[0031] For example, a microencapsulated insect repellent can be used as the melt-kneaded insect repellent. A microencapsulated insect repellent is one in which the insect repellent is packed into microcapsules. In particular, using a liquid compound insect repellent allows for stable addition of a high concentration of the insect repellent and facilitates adjustment of the diffusion rate of the insect repellent within the thermally bondable non-circular fiber. However, when a liquid compound insect repellent is used, the insect repellent may significantly bleed out near the outer surface of the thermally bondable non-circular fiber. This can lead to tackiness (adhesion) between the fibers, making weaving difficult, or the insect repellent may volatilize during spinning, resulting in the need for more insect repellent than necessary. In such cases, using a microencapsulated insect repellent can keep the liquid compound insect repellent within the microcapsules during melt spinning and prevent it from migrating near the outer surface, making it easier to prevent significant bleed-out. This reduces the likelihood of tackiness and prevents the use of more insect repellent than necessary.

[0032] The thermally adhesive non-circular fibers used in the insect repellent net of the present invention may also contain functional materials that impart other functions than insect repellency. Examples of such functional materials include titanium dioxide as a matting agent, calcium stearate as a lubricant, fine particles of silica or alumina, hindered phenol derivatives as antioxidants, and additives such as colorants (pigments), stabilizers, and dispersants, as well as ultraviolet shielding agents, near-infrared shielding agents, antibacterial agents, antifungal agents, antistatic agents, flame retardants, weather resistance agents, and various catalysts. The functional materials may be dispersed within the thermally adhesive non-circular fibers together with the insect repellent, or may be attached to the surface.

[0033] The thermally bondable non-circular fiber used in the insect net of the present invention can be used for either the warp or weft of the insect net, or for both. For example, by using the thermally bondable non-circular fiber of the present invention for the weft of the insect net and a high-strength fiber other than the thermally bondable non-circular fiber for the warp, it is possible to achieve both pest repellency and strength of the insect net. Alternatively, the thermally bondable non-circular fiber of the present invention and other high-strength fibers can be arranged in any pattern for both the warp and weft and knitted or woven.

[0034] In addition, the thermally bondable non-circular fibers of the present invention may be used in such a manner that fibers having different non-circular cross sections are used for either or both of the warp and weft yarns, and it is also possible to use a combination of fibers having different degrees of non-circularity for either or both of the warp and weft yarns of a net.

[0035] In the insect repellent net of the present invention, the proportion of the thermally adhesive non-circular fibers is preferably 20% or more, more preferably 50% or more, in order to prevent a decrease in the effectiveness of the insect repellent and a decrease in reflected light and to obtain sufficient pest repellency. The "proportion of the thermally adhesive non-circular fibers" referred to here refers to the proportion (mass%) of the thermally adhesive non-circular fibers in the total fibers constituting the insect repellent net of the present invention.

[0036] In the insect net of the present invention, the mesh size is in the range of 0.8 to 3.0 mm, and more preferably in the range of 0.8 to 1.0 mm. By making the mesh size 0.8 mm or more, good breathability and a moderate room temperature can be maintained, and good growth of crops and increased yields can be expected. By making the mesh size 3 mm or less, it becomes difficult for pests to invade.

[0037] The insect net of the present invention is formed from a large number of meshes, and the shape of the meshes is preferably a polygon such as a square, rectangle, hexagon or octagon, and is particularly preferably a square or rectangle. The mesh size of the insect control net of the present invention means the size of the gaps created by the mesh. If the mesh shape is square, it is expressed by the length of one side, if it is rectangular, it is expressed by the length of the long side, and if it is hexagonal or octagonal, it is expressed by the length of the diagonal.

[0038] Among the insect nets of the present invention, those in which the intersections of the thermally adhesive non-circular fibers are thermally bonded can be obtained by knitting or weaving the thermally adhesive non-circular fibers into a net shape and then, simultaneously with or after weaving, heating the resulting knitted or woven fabric to a temperature above the temperature at which the intersections of the thermally adhesive non-circular fibers fuse. The weaving pattern of the insect net of the present invention is not limited. That is, the arrangement of the thermally adhesive non-circular fibers used in the warp and weft, the number of threads per unit length, and other factors can be set as desired. Examples of weaving structures include plain weave, twill weave, satin weave, leno weave, and Russell weave, but plain weave is preferred in terms of knitting and weaving properties, ease of mesh size adjustment, and insect resistance. The number of threads of the thermally adhesive non-circular fibers to be woven is determined appropriately depending on the type of crop for which the insect net of the present invention is to be used, the type and size of pest insects, and other factors.

[0039] Examples of devices for heating and thermally bonding the intersections of the knitted or woven fabric include hot air heaters, infrared heaters, far-infrared heaters, high-pressure steam heaters, ultrasonic heaters, hot roll heaters, and thermocompression roll heaters, which may be used alone or in combination. In particular, using a device that combines a hot air heater and a hot roll heater, or a hot air heater and a thermocompression roll heater, can provide an insect net with high bonding strength at the intersections.

[0040] There are no particular limitations on the method of using the insect control net of the present invention, and it may be used in methods such as tunnel laying or flat laying in which supports are used to cover crops with the agricultural insect control net, house side laying in which the agricultural insect control net is laid on the side of a vinyl greenhouse, full-surface laying in which the entire outer surface of a vinyl greenhouse is covered with the agricultural insect control net, and solid laying in which crops are covered without supports, etc. House side laying is preferred from the viewpoint of maximizing the effects of the present invention.

[0041] The insect control net of the present invention can be used for cultivating crops that may be infested by pests. Here, pests refer to insects that cause damage to humans, livestock, pets, and agricultural products. Pests are classified into sanitary pests, agricultural pests, food pests, etc. depending on the target of the damage they infest. Examples of agricultural pests include scale insects, ants, thrips, whiteflies, bedbugs, and weevils. The insect control net of the present invention is preferably used against agricultural pests, but can also be expected to have a repellent and control effect against pests classified as sanitary pests, food pests, etc., as long as there are no particular obstacles.

[0042] Pests include not only insects but also mites and arachnids, such as Diptera (Diptera), Blattaria (Blattaria), Dermaptera (Dermaptera), Hemiptera (Hemiptera), Hymenoptera (Hymenoptera), Orthoptera (Orthoptera), Isoptera (Termites), Araneida (Araneida), Lepidoptera (Lepidoptera), Coleoptera (Coleoptera), Thysanoptera (Thysanoptera), Acarina (Acari), Chilopoda (Chilopoda), and Diplopoda (Diplopoda).

[0043] The insect control net of the present invention particularly contributes favorably to reducing damage caused by coccoids, ants, thrips, whiteflies, bedbugs and weevils. Scale insects are insects belonging to the superfamily Coccoidea, and include the palm scale insect (Abgrallaspis cyanophylli), red scale insect (Aonidiella aurantii), red scale insect (Aonidiella inornata), male Becky scale insect (Aonidiella orientalis), pale scale insect (Aspidiotus destructor), red spotted scale insect (Chrysomphalus aonidum), onion scale insect (Chrysomphalus dictyospermi), orchid scale insect (Diaspis boisduvalii), palm scale insect (Hemiberlesia lataniae), black scale insect (Ischnaspis longirostris), and long-legged scale insect (Pinnaspis buxi), Pseudaulacaspis cockerelli, Papaya scale (Pseudaulacaspis papayae), and other scale insects of the Coccidae family; Coccidae scale insects such as Coccidae hesperidum, Coccidae viridis, Eucalymnatus tessellatus, and Saissetia coffeae; Coccidae scale insects such as Icerya aegyptiaca, and other scale insects of the Coccidae family; Steatococcus samaraius, pineapple mealybug (Dysmicoccus brevipes), banana mealybug (Dysmicoccus neobrevipes), two-striped mealybug (Ferrisia virgata), Nipaecoccus nipae, citrus mealybug (Planococcus citri), Planococcus minor, banana mealybug (Pseudococcus elisae), bead ray mealybug (Pseudococcusjackbeardsleyi, Pseudococcus orchidicola, and other scale insects of the Pseudococcidae family. Ants are insects that belong to the ant family (Formicidae), and examples include the white fire ant (Anoplolepis gracilipes), Brachymyrmex obscurior, the Australian carpenter ant (Camponotus consobrinus), Camponotus pennsylvanicus, Camponotus variegatus, the brown ant (Lasius niger), Nylanderia vaga, Nylanderia bourbonica, the Australian weaver ant (Oecophylla smaragdina), the long-horned fire ant (Paratrechina longicornis), the light-spotted fire ant (Plagiolepis alluaudi), and ants of the genus Solenopsis. Thrips are insects belonging to the order Thripida, and examples include Chaetanaphothrips signipennis, Chaetanaphothrips clarus, Chaetanaphothrips orchidii, Hercinothrips bicinctus, Hercinothirps femoralis, Thrips florum, Thrips hawaiiensis, Frankliniella parvula, and Elixothrips brevisetis. Whiteflies are insects belonging to the order Hemiptera, and examples include the greenhouse whitefly (Trialeurodes vaporariorum), tobacco whitefly (Bemisia tabaci), silverleaf whitefly (Bemisia argentifolii), citrus whitefly (Dialeurodes citri), citrus spiny whitefly (Aleurocanthus spiniferus), and lesser whitefly. Bed bugs are insects belonging to the Hemiptera order, and examples include the bed bug (Cimex hemipterus) and the netted bed bug. Weevils are insects that belong to the superfamily Curculionoidea, and examples include the banana weevil (Cosmopolites sordidus), the banana weevil (Odoiporus longicollis), and the banana weevil (Polytus mellerborgi).

[0044] The insect control net of the present invention can effectively control thrips and whiteflies in particular. Thrips and whiteflies parasitize a wide variety of crops, so it is not possible to generalize the target of use, but in the case of food crops, for example, the net can be applied to crops of the Cucurbitaceae family, such as watermelon and cucumber; the Solanaceae family, such as tomatoes, bell peppers, eggplants, shishito peppers, and tobacco; the Rutaceae family; the Amaryllidaceae family, such as leeks; the Brassicaceae family, such as cabbage; the Chenopodiaceae family, such as spinach; and the Fabaceae family, such as kidney beans.

[0045] Among food crops, it is particularly preferable to use it for growing crops of the Cucurbitaceae or Solanaceae families. These crops are particularly susceptible to damage from thrips and whiteflies, and are particularly susceptible to viral infections transmitted by thrips and whiteflies. Moreover, because the cultivation period is during the warm season, thrips and whiteflies are active and damage is likely to spread. In addition, many crops belonging to these families, such as tomatoes and peppers, require control of both temperature and ventilation (humidity) during cultivation.

[0046] The insect control net of the present invention is also suitable for use in the cultivation of flowering plants such as lisianthus and chrysanthemums. Flowering plants are highly required to be grown without blemishes or color spots on the petals, stems, and leaves, so that they are worthy of admiration. However, when infested by thrips or whiteflies, they inadvertently suck out the sap, causing white spots or deformations on the flowers and leaves. Furthermore, the sticky excrement of whiteflies adheres to the plants, damaging their appearance. Therefore, flowering plants are particularly in need of thrips and whiteflies control. [Example]

[0047] The present invention will be explained in more detail with reference to examples and comparative examples, but the present invention is not limited thereto. <Test Method> Test methods relating to the present invention will be explained below. (a) Heteromorphic degree: The degree of irregularity is the value obtained by dividing the cross-sectional perimeter (L1) of a fiber by the perimeter (L2) of a circle having the same area as the cross-sectional area, and was calculated by the following formula (1). Anomaly degree=L1÷L2 (1) Using Figure 1, we will explain how to calculate the irregularity degree with an example. In Figure 1, two rectangles, ABCD and EFGH, each measuring 1.00 mm x 2.00 mm, overlap to form a regular cross, and a=d=1.00 mm, b=c=0.50 mm, and e=f=2.00 mm. The perimeter of this regular cross, i.e., the sum of the lengths of the solid line portions, is 8.00 mm (L1). The area of ​​the diagonally shaded portion of this regular cross is 3.00 mm. 2 Therefore, the radius of a circle with the same area is 0.977 mm, and the circumference of the circle is calculated to be 6.14 mm (L2). Therefore, the irregularity of this shape is calculated by dividing the value of L1 by the value of L2, so the irregularity is calculated to be 1.30.

[0048] (b) Pest repellency: The pest repellency test method is explained using Figure 2. An insect net 3 was attached between the cylindrical insect release section 2 (outer diameter 100 mm, inner diameter 90 mm, length 300 mm) and the cylindrical transport section 4 (outer diameter 90 mm, inner diameter 80 mm, length 50 mm) to prevent the movement of pests. A crop 7 to attract pests was placed in a cubic box-shaped attraction section 5 (300 mm side length, 5 mm thickness). A predetermined number (Y) of pest insects 6 were then released into the insect release section 2. The number (Z) of pest insects that had migrated to the attraction section 5 after a predetermined time was counted, and the pest repellency rate after the predetermined time was calculated using the following formula (2). The insect release section 2, transport section 4, and attraction section 5 are made of transparent acrylic, allowing the number of pests to be visually observed. Pest repellency rate after a given time (%) = (YZ) ÷ Y × 100 (2) The higher the pest repellency rate, the greater the pest repellency effect. The test was conducted in a sunny glass room where sunlight similar to natural light was available and where the pests would not escape, and the pests were killed with chemicals after the test.

[0049] (c) Etofenprox content: The cut fibers were heated at 170°C for 10 minutes and then cooled to room temperature to prepare evaluation samples. The evaluation samples were immersed in a solvent for at least two days, and the etofenprox component extracted into the solvent was quantified by high-performance liquid chromatography (HPLC). The etofenprox content was calculated from the mass W of etofenprox contained in the solvent using the following formula (3): Etofenprox content (mass%) = W ÷ (mass of evaluation sample) × 100 (3)

[0050] (d) Volume ratio of sheath-core (V1 / V2): The cross section of the thermal adhesive fiber was observed using a microscope (model: VHX-500F) manufactured by KEYENCE Corporation. For the cross section of the fiber in the obtained microscope image, the volume V2 of the sheath part of the sheath-core structure and the volume V1 of the core part were measured using the image processing function attached to the device, and the volume ratio (V1 / V2) was calculated.

[0051] <Production Example 1> The sheath component was made of an ethylene-propylene binary copolymer with a melting point of 134°C, and the core component was made of polypropylene with a melting point of 164°C. An insect repellent (ethofenprox microcapsules) was blended into both the sheath and core components to produce thermally bondable non-circular fiber 1, which had a Y-shaped cross section. The etofenprox content of thermally bondable non-circular fiber 1 was 0.27% by mass, and the degree of irregularity was 1.235. Furthermore, the fineness of thermally bondable non-circular fiber 1 was 322 dtex, and the volume ratio of the core to the sheath (V1 / V2) was 70 / 30. Figure 3 shows the cross section of thermally bondable non-circular fiber 1.

[0052] <Production Example 2> The sheath component was made of an ethylene-propylene binary copolymer with a melting point of 134°C, and the core component was made of polypropylene with a melting point of 164°C. An insect repellent (ethofenprox microcapsules) was mixed into both the sheath and core components to produce thermally bondable non-circular fiber 2 with a Y-shaped cross section. The etofenprox content of thermally bondable non-circular fiber 2 was 0.27% by mass, and the degree of irregularity was 1.196. The fineness of thermally bondable non-circular fiber 2 was 200 dtex, and the volume ratio of the core to the sheath (V1 / V2) was 70 / 30. Figure 4 shows the cross section of thermally bondable non-circular fiber 2.

[0053] <Production Example 3> Thermally bondable fiber 3 with a circular cross section was produced using an ethylene-propylene binary copolymer with a melting point of 134°C for the sheath component and polypropylene with a melting point of 164°C for the core component, without kneading any insect repellent into either the sheath or core. The fineness of thermally bondable fiber 3 was 322 dtex, and the volume ratio of the core to the sheath (V1 / V2) was 60 / 40. Figure 5 shows the cross section of thermally bondable fiber 3.

[0054] <Production Example 4> Thermally bondable fiber 4, with a circular cross section, was produced using an ethylene-propylene binary copolymer with a melting point of 134°C for the sheath component and polypropylene with a melting point of 164°C for the core component, without kneading any insect repellent into either the sheath or core. The fineness of thermally bondable fiber 4 was 200 dtex, and the volume ratio of the core to the sheath (V1 / V2) was 60 / 40. Figure 6 shows the cross section of thermally bondable fiber 4.

[0055] Example 1 A plain weave net with a mesh size of 1.0 mm was woven using thermal adhesive non-circular fibers 1 as the weft and thermal adhesive fibers 3 as the warp. This net was heat-treated at 160-165°C using a hot air heater to obtain insect netting 1 in which the intersections of the thermal adhesive fibers were thermally bonded. The thermal adhesive non-circular fibers 1 accounted for 50% by mass of the fibers constituting insect netting 1. When this net was used to evaluate its pest repellency, it showed good pest repellency rates of 39% after 2 hours, 36% after 4 hours, and 36% after 5 hours. Note that a pest repellency rate of 30% or more is sufficient.

[0056] Example 2 A plain weave net with a mesh size of 0.8 mm was woven using thermal adhesive non-circular fibers 2 as the weft and thermal adhesive fibers 4 as the warp. This net was heat-treated at 160-165°C using a hot air heater to obtain an insect net 2 in which the intersections of the thermal adhesive fibers were thermally bonded. The thermal adhesive non-circular fibers 2 accounted for 50% by mass of the fibers constituting the insect net 2. When the pest repellency was evaluated using this net, it showed a good pest repellency similar to that of Example 1.

[0057] It is clear that the insect repellent net of the present invention exhibits particularly favorable pest repellency. Furthermore, by thermally bonding the intersections of the fibers, the insect repellent net of the present invention does not cause misalignment of the weave, can prevent the entry of pests blown by wind, etc., and has good breathability.

[0058] In the above examples, a Y-shape was used as the modified shape of the thermally adhesive modified fiber, but similar effects can be expected with other modified shapes. Furthermore, although etofenprox was used as the insect repellent, similar effects can be expected with other insect repellents. Because the insect repellent net of the present invention has excellent pest repellency, it can be used not only as an agricultural insect repellent net, but also for construction, home, and many other purposes. Furthermore, the insect repellent net of the present invention can also be used in combination with many other materials, such as fabrics, films, metal nets, construction materials, civil engineering materials, and agricultural materials. [Industrial Applicability]

[0059] The thermally adhesive non-circular fiber of the present invention is useful as a material for insect-repellent fiber products, and by knitting or weaving it into a net, an insect-repellent net having excellent weather resistance and durability of insect-repellent performance can be provided. [Explanation of symbols]

[0060] 1. A figure with overlapping cross shapes 2. Insect Release Department 3. Insect net 4. Moving part 5. Attractive part 6. Pests 7. Crops for attracting pests 101...Cross section of thermally adhesive non-circular fiber 1 102...Cross section of thermally adhesive non-circular fiber 2 103...Cross section of thermal adhesive fiber 3 104...Cross section of thermal adhesive fiber 4

Claims

1. This insect-proof net is made by thermally bonding the intersections of fibers, and the fibers constituting the insect-proof net are thermally bonded irregular fibers having a degree of irregularity in the range of 1.10 to 2.20 and containing a microencapsulated insect repellent kneaded into the fibers, and the mesh size of the insect-proof net is in the range of 0.8 to 3.0 mm. Here, the thermally adhesive irregular fiber has a sheath-core structure, the ratio (V1 / V2) of the core volume V1 to the sheath volume V2 is in the range of 50 / 50 to 90 / 10, and the microencapsulated insect repellent is contained together with the sheath core of the thermally adhesive irregular fiber.

2. 2. The insect net according to claim 1, wherein the thermally adhesive non-circular fiber has a fineness in the range of 100 to 5,000 dtex.

3. 3. The insect control net according to claim 1, wherein the insect repellent is a pyrethroid compound.

4. The insect repellent net according to any one of claims 1 to 3, wherein the proportion of the thermally adhesive non-circular fibers is 20 mass % or more of the total fiber amount.

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