AU2013335918B2

AU2013335918B2 - Chemical volatilization body

Info

Publication number: AU2013335918B2
Application number: AU2013335918A
Authority: AU
Inventors: Tomohiro Kakinoki; Seiichi Kashima; Yumi Kawajiri; Masuo Matsumoto; Koji Nakayama
Original assignee: Dainihon Jochugiku Co Ltd
Current assignee: Dainihon Jochugiku Co Ltd
Priority date: 2012-10-22
Filing date: 2013-10-15
Publication date: 2016-11-17
Anticipated expiration: 2033-10-15
Also published as: CN104735978A; JPWO2014065150A1; JP6199877B2; JP6529554B2; JP2017209111A; JP6408091B2; AU2013335918A1; TW201422156A; TWI555470B; JP2018011601A; KR102036951B1; WO2014065150A1; HK1211791A1; CN104735978B; KR20150070368A

Abstract

Provided is a chemical volatilization body which maintains volatilization performance even if rained upon. A chemical volatilization body comprising a structural body provided with a mesh comprising a fibrous material including a normal-temperature-volatile pyrethroid insecticide component, is characterized in that: the fibrous material comprises resin filaments; and the water retention ratio, i.e. the amount of water capable of being retained by the structural body relative to the weight of the structural body, is in the range 0.005 to 0.5 inclusive.

Description

DESCRIPTION CHEMICAL VOLATILIZER

TECHNICAL FIELD

[0001]

The present invention relates to a chemical volatilizer for controlling and repelling flying insect pests such as mosquitos, black flies and the like. More specifically, the present invention relates to a chemical volatilizer composed of a structure comprising a mesh made of a fibrous product containing a pyrethroid insecticide component volatile at room temperature.

BACKGROUND ART

[0002]

Conventionally, insecticides are known which achieve control and repelling of insect pests through volatilization of insecticide components volatile at normal temperature into air.

For example, the below-identified Patent Document 1 discloses a chemical volatilizer composed of several sheets of net-like products made of twisted yams, which are impregnated with an insecticide component.

Further, the below-identified Patent Document 2 discloses a molded article for insect pest control, which is a resin molded article on the surface of which a plurality of grooves are formed at intervals of 300 pm or less, so that stickiness due to an active ingredient for insect pest control can be prevented.

PRIOR ART DOCUMENTS PATENT DOCUMENTS

[0003]

Patent Document 1: JP 2001-200239 A

Patent Document 2: JP 2009-19015 A

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0004]

These insect repelling devices are most frequently used suspended near a window or at an entrance, and thus, they could sometimes be a nuisance or an eyesore.

In order to solve these problems, the overall size or the thickness of the insect repellent device can be reduced to make their presence less conspicuous.

[0005]

However, the chemical volatilizer disclosed in Patent Document 1 is composed of plate-like mesh sheets made of a resin such as polyethylene terephthalate (PET), which is basically non-absorbent to insecticide components, and although twisted yams constituting the mesh sheets are impregnated with an insecticide component, the insecticide component is only attached to or impregnated into the region of the yams close to the surface. Therefore, although there are cases where, when the twisted yam is cut in cross section, the insecticide component is present at the central area of the yam distant from the outer peripheral portion depending on the shape of the yam in cross section, the volatilization rate of the insecticide component is extremely high.

For this reason, even though the chemical volatilizer is capable of exhibiting a relatively high insecticidal effect during the initial stage of the use, it is unable to sustain its effect long enough for a long-term use of over 100 days or more. Further, since the insecticide component is present in the vicinity of the surface of the twisted yam, it is susceptible to the influence of rain when used in an outdoor environment, and the outflow loss of the insecticide component was unavoidable.

[0006]

On the other hand, in the molded article for insect pest control disclosed in Patent Document 2, the active ingredient for insect pest control is carried by a resin carrier in a kneaded state, and thus, it is characterized by having a reduced and stable volatilization rate of the active ingredient for insect pest control compared with that of the chemical volatilizer disclosed in Patent Document 1. However, when the molded article is exposed to rain, there are cases where the volatilization of the active ingredient for insect pest control is inhibited by water, posing a potential risk of reducing the insecticidal effect of the chemical volatilizer.

[0007]

In view of the conventional problems as described above, the present inventors have investigated the influence of rain on the chemical volatilizer, using: a chemical volatilizer composed of a mesh made of resin filaments which are obtained by kneading a pyrethroid insecticide component volatile at room temperature into a resin carrier and by molding the kneaded mixture; or a chemical volatilizer composed of a three-dimensional structure comprising a mesh made of twisted resin filaments, which structure is impregnated with a pyrethroid insecticide component volatile at room temperature. In other words, the present invention provides a chemical volatilizer that may be capable of maintaining its ability to allow volatilization of the chemical even when it is exposed to rain.

MEANS FOR SOLVING THE PROBLEMS

[0008]

The present inventors have discovered that, the chemical volatilizer having the following constitutions is capable of exhibiting an excellent effect for achieving the above mentioned invention. (1) A chemical volatilizer composed of a structure comprising a mesh made of a fibrous product containing a pyrethroid insecticide component volatile at room temperature; characterized in that the fibrous product is composed of resin filaments, and a water retention ratio of the structure, which is the ratio of the amount of water the structure can hold relative to the weight of the structure, is 0.005 or more and 0.5 and or less. (2) The chemical volatilizer as recited in (1), wherein the size of a single mesh in a mesh portion of the structure is 10 ram2 or more and 200 mm" or less, (3) The chemical volatilizer as recited in (1) or (2), wherein the resin filaments are obtained by kneading the pyrethroid insecticide component volatile at room temperature into a resin carrier and then by molding the resulting kneaded mixture.

EFFECT OF THE INVENTION

[0009]

The chemical volatilizer according to the present invention has a water retention ratio, which is the ratio of the amount of water a structure can hold relative the weight of the structure, within a predetermined range. Therefore, when the chemical volatilizer is placed outdoors and exposed to rain, it is possible to reduce the inhibition of the volatilization of the pyrethroid insecticide component volatile at room temperature, due to adhesion of rain water.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 is a perspective view showing an example of a planar net. FIG. 2 (a) is a perspective view showing an example of a three-dimensional structure; FIG. 2 (h) is a front view' of the three-dimensional structure shown in (a); and FIG. 2 (c) is a cross sectional view of die three-dimensional structure shown in (b) taken along the line c~e.

MODE FOR CARRYING OUT THE INVENTION

[0011]

The chemical volatilizer according to the present invention is composed of a structure comprising a planar or three-dimensional mesh made of a fibrous product containing a pyrethroid insecticide component volatile at room temperature.

[0012] [Pyrethroid insecticide component volatile at room temperature]

As the pyrethroid insecticide component volatile at room temperature, those having characteristics of volatilizing into air at room temperature and having a vapor pressure at 25°C of about 0.001 Pa or more and 0.1 Pa or less are preferred.

Specifically, the use of at least one of metofluthrin, profluthrin, transfluthrin, and empenthrin is preferred, in terms of its ability to volatilize, safety and the like. While various optical isomers or geometric isomers of these insecticide components exist, any of the isomers can be used alone or as a mixture thereof.

[0013] [Fibrous product]

The fibrous product refers to a product formed in the form of fiber, and includes a continuous fiber (filament) alone, a fiber obtained by twisting continuous fibers and/or short fibers, and the like. In general, the use of a twisted fibrous product tends to increase the water retention ratio. However, as long as the value of the water retention ratio of the twisted fibrous product is within a predetermined range, the effect of the present invention can be achieved and it poses no practical problem. In the present invention, a continuous fiber (filament) is preferably used. In particular, it is preferred that a continuous fiber made of a resin (resin filament) obtained by molding a resin composition containing a resin carrier to be described later be used as a material, because the durability of the fibrous product can be increased, and it is therefore preferred.

[0014]

In the present invention, the above mentioned resin filament contains the pyrethroid insecticide component volatile at room temperature. Examples of the method for incorporating the pyrethroid insecticide component volatile at room temperature into the resin filament include: a method in which the pyrethroid insecticide component volatile at room temperature is kneaded into the resin carrier to be described later to prepare the resin composition to be described later, and the resulting composition is then molded to obtain resin filaments; and a method in which the resin composition to be described later is molded to obtain resin filaments, and the resulting resin filaments are twisted to form a mesh, which is then impregnated with the above mentioned pyrethroid insecticide component volatile at room temperature.

[0015]

Examples of the method for molding the resin composition to be described later include: a method in which the resin composition to be described later is subjected to extrusion molding or injection molding to obtain resin filaments, which is then formed into a mesh; and a method in which the resin composition to be described later is directly formed into a mesh composed of resin filaments, by injection molding or the like.

[0016] [Resin composition]

The resin composition is obtained by kneading the resin carrier with a fine powder carrier and another resin carrier(s) as required. From the viewpoint of efficiency, it is preferred that this resin composition be formed into pellets once, and then the pellets be subjected to molding as described above.

[0017] [Resin carrier]

The preferred resin carrier somewhat varies depending on whether the pyrethroid insecticide component volatile at room temperature is kneaded into the resin carrier or the resin carrier is impregnated with the pyrethroid insecticide component.

In the case of the former, the insecticide component is not particularly limited, as long as the insecticide component incorporated into the resin carrier is capable of gradually bleeding to the surface of the carrier to volatilize. Examples thereof include polyolefin resins such as polyethylene resin and polypropylene resin, and those obtained by polymerization of the above mentioned resin with a monomer such as carboxylic acid ester, followed by molding. As used herein, the monomer such as carboxylic acid ester is one which is effective in controlling the volatilization of the insecticide component from the surface of the resin carrier. Examples thereof include methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, vinyl acetate and the like.

[0018]

In general, the higher the content of the carboxylic acid ester monomer relative to that of the polyolefin resin, the slower the bleeding rate of the insecticide component tends to be. Therefore, the content of the carboxylic acid ester monomer may be adjusted as appropriate within the range of from 1 to 30% by mass relative to the amount of the polyolefin resin, depending on the type and the content of the insecticide component used, or on the purpose of use and the like.

[0019]

Further, as the resin carrier, it is possible to use a polymer blend prepared in advance by mixing a polyolefin copolymer which contains a large amount of carboxylic acid ester monomer and an olefin homopolymer, with their content ratio adjusted. In addition, it is also possible to incorporate another high molecular compound(s) such as styrene thermoplastic elastomer and the like, as required.

[0020]

In the present invention, an ethylene-vinyl acetate copolymer is preferred as the resin carrier in terms of performance, usability and the like, and the ratio of ethylene units to vinyl acetate units in the copolymer is preferably from 90:10 to 70:30. It is because, if the amount of the vinyi acetate unit is too small, the physical properties of the ethylene-vinyl acetate copolymer becomes almost the same as that of polyethylene, and the effect of controlling the bleeding required in the present invention is hardly expected. On the other hand, if the amount of vinyl acetate unit is too large, it complicates the molding of the resin into pellets.

[0021]

In addition, the ethylene-vinyl acetate copolymer preferably has a melt mass flow rate (MFR) of 5 g/10 min or more and 50 g/10 min or less. Too small a value of MFR could compromise the effect of controlling the bleeding, while too large a value of MFR may have an unignorable impact on the physical properties of the resin pellets.

[0022]

On the other hand, in the chemical volatilizer of the type in which the resin carrier is impregnated with the pyrethroid insecticide component volatile at room temperature, typically, a resin which is non-absorbent to the insecticide component such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or the like is primarily used as the resin carrier.

In this type of chemical volatilizer, the insecticide component is carried by the surface of the resin carrier formed in the shape of a planar or three-dimensional mesh, to allow the volatilization of the insecticide component. It is also possible to further incorporate into the resin carrier, a resin(s) such as the above mentioned polyolefin resin, styrene thermoplastic elastomer, rayon or the like, to modify the properties of the resin carrier, and thereby controlling the volatility of the insecticide component.

The chemical volatilizer of the type in which pyrethroid insecticide component volatile at room temperature is kneaded into the resin carrier will now be described in detail.

[0023] [Fine powder earner]

The fine powder carrier used in the present invention is a component which can be added to the resin carrier so that the pyrethroid insecticide component volatile at room temperature can be carried in the resin pellets. Examples thereof include microcrystalline silica and silicic acid fine powder, known as white carbon; diatomaceous earths; zeolites; clay minerals; wood flour and the like.

[0024]

The fine powder earner preferably has a number average particle diameter of 1 pm or more and 30 pm or less, more preferably, 5 pm or more and 20 pm or less. If the number average particle diameter of the fine powder earner is greater than 30 pm, its ability to carry the insecticide component is reduced due to insufficient surface area, even if it is present within the content range as described above, and the resulting resin pellets are more likely to be sticky. On the other hand, particulates of less than 1 pm in size are not preferred, because it is difficult to actually realize, and the physical properties thereof may be significantly altered.

[0025]

As the fine powder earner, one which does not react with the insecticide component and which has a large surface area, such as microcrystalline silica known as white carbon can be used. The fine powder carrier prevents stickiness by carrying the insecticide component. Therefore, the resin composition itself, obtained by kneading the resin component with the fine powder carrier, is also less likely to he sticky, making it suitable for use as a master batch.

[0026] [Other resin carrier]

Further, the resin composition may contain another resin carrier(s) in addition to the resin carrier such as the above mentioned ethylene-vinyl acetate copolymer, for the purpose of adjusting the weight of the resin composition or controlling the physical properties thereof. As the other resin carrier, the resin composition may contain a polyolefin resin or styrene resin. Examples of the polyolefin resin include polyethylene (PE), polypropylene (PP) and the like. Among these, polyethylene is preferred in terms of affinity with the ethylene-vinyl acetate copolymer or ethylene-methyl methacrylate copolymer. In particular, a low density polyethylene, specifically, a branched low density polyethylene (LDPE), straight chain low density polyethylene (LLDPE) is preferred in terms of moldability.

[0027] [Content ratio]

The content of the resin carrier relative to the total amount of the resin composition is preferably 10% by mass or more, more preferably 20% by mass or more, if the content of the resin earner is less than 10% by mass, the effect of inhibiting excessive bleeding becomes insufficient. On the other hand, the upper limit thereof is preferably 90% by mass or less, more preferably 60% by mass or less, it is because, too large a content of the resin carrier poses a potential risk that the bleeding of the chemical is inhibited excessively to such an extent as to excessively reduce the insecticidal effect brought by the volatilization of the pyrethroid insecticide component volatile at room temperature, thereby compromising the intended purpose of the invention; this is so even in cases where the resin molded article is obtained by kneading the pellets of the resin composition, as the master batch, with the other resin earner. According to the present invention, it is possible to control the bleeding of the resulting resin pellets to be within an appropriate range, by incorporating 10% by mass or more and 90% by mass or less of ethylene-vinyl acetate copolymer and/or ethylene-methyl methacrylate copolymer.

[0028]

The content of the fine powder earner relative to the total amount of the resin composition is preferably 30% by mass or less, more preferably 25% by mass or less.

If the content is greater than 30% by mass, when the resin composition is pelletized, it becomes difficult to maintain the shape of the pellets, due to inappropriate balance between the content of the resin carrier and the fine powder carrier. Further, since the fine powder carrier will also be included in the molded article formed from the resin composition, too large a content of the fine powder carrier may have an impact on the physical properties of the chemical volatilizer.

The lower limit of the content of the fine powder carrier relative to the total amount the resin composition is not particularly limited. However, in cases where inhibition of excessive bleeding is required, it is preferred that the lower limit be set to 10% by mass or more. If the content is less than the above mentioned lower limit, the effect of inhibiting the bleeding may be insufficient.

[0029] [Production of resin composition and pellets]

The above mentioned resin composition can be obtained by heating the resin carrier, and then kneading the heated resin carrier with the pyrethroid insecticide component volatile at room temperature, and with the fine powder earner and/or the heated other resin carrier as required. The resulting resin composition is then pelletized and cooled to obtain pellets.

[0030]

The appropriate heating temperature varies depending on the type of the resin of the resin carrier and the type of resin of the other resin carrier, but it is usually from about 100 to 140°C. For example, the melting temperature of the ethylene-vinyl acetate copolymer (Ultracen 710; manufactured by Tosoh Corporation) to be described later is 70°C, and thus the copolymer can be sufficiently kneaded at the above mentioned heating temperature. Since too high a temperature may cause the thermal decomposition and/or diffusion loss of the pyrethroid insecticide component volatile at room temperature, the heating temperature higher than 140°C is not preferred.

[0031] hi view of the above, the following combination of materials can be mentioned as an exemplary composition of the resin composition: 10% by mass or more and 60% by mass or less of the pyrethroid insecticide component volatile at room temperature; 30% by mass or less of the fine powder earner, and 10% by mass or more and 60% by mass or less of the resin carrier such as ethylene-vinyl acetate copolymer.

[0032] [Timing of mixing other resin carrier]

The above mentioned other resin carrier may be incorporated during the production stage of the pellets of the resin composition. Alternatively, the resin composition may be pelletized without incorporating the other resin carrier, and then the resulting pellets may be diluted with the other resin carrier, followed by kneading and molding, to obtain the chemical volatilizer.

[0033]

The dilution ratio at this time is preferably about 1.5 times or more, and the upper limit thereof is preferably about 5 times. The dilution ratio of less titan 1.5 times eliminates the benefit of diluting, whereas the dilution ratio of greater than 5 times inevitably leads to the problem that the content of the insecticide component is reduced.

[Chemical volatilizer]

The chemical volatilizer is obtained by molding the pellets made of the above mentioned resin composition. As mentioned above, in cases where the resin pellets containing the insecticide component do not contain the other resin earner, the resin pellets containing the insecticide component may be diluted with the other resin carrier, followed by kneading and molding to obtain a chemical volatilizer.

[0035]

This chemical volatilizer is a structure composed of resin filaments formed into, preferably, the shape of a three-dimensional mesh. Examples of the molding method of the chemical volatilizer include: a method in which the resin pellets are molded by extrusion molding, injection molding or the like to obtain resin filaments, which are then formed into a mesh; and a method in which the resin pellets containing the insecticide component are directly molded into the form of a mesh by crossing a plurality of resin filaments, by injection molding or the like.

[0036]

Examples of the mesh structure include a planar net 1 as shown in FIG. 1 and a three-dimensional structure 2 as shown in FIG. 2 (a) to FIG, 2 (c). The shape of the chemical volatilizer having the above described mesh structure is not limited to these examples.

[0037]

The planar net shown in FIG. 1 is formed by crossing the above mentioned filaments in a grid-like formation so as to form a planar grid structure.

[0038]

The three-dimensional structure 2 shown in FIG. 2 (a) to FIG. 2 (e) is a structure in which the filaments of rectangular corrugated members 21 shown in FIG. 2 (c) are arranged so as to intersect the apexes of the two pieces of corrugated members 21 at approximately a right angle. Further, the three-dimensional structure 2 is reinforced by a linear, rod-shaped reinforcing member 22 which intersects and connects together at least two apexes contained in one apex-containing surface. The apex-eontaining surface as used herein refers to a surface which constitutes the three-dimensional structure and contains apexes, [0039]

In the three-dimensional structure 2 having the above mentioned structure, the surface area of the filaments present within a certain volume is increased compared with that of the planar net 1. In addition, the use of the reinforcing member 22 allows for a further increase of the surface area of the filaments, and an increase in the strength of the three-dimensional structure.

The peripheral portion of the three-dimensional structure is designed and shaped as appropriate in relation with the strength, shape, external container and the like of the three-dimensional structure.

[0040] [Water retention ratio ]

The water retention ratio of the structure, in other words, the amount of water the structure can hold relative to the weight of the structure (the amount of water the structure can hold (parts by weight) / the weight of the structure (parts by weight)), is preferably 0,005 or more, and more preferably 0.01 or more. The water retention ratio of less than 0.005 may cause inconveniences in the production of the structure, for example, in the molding of the mesh . On the other hand, the upper limit of the water retention ratio is preferably 0.5, and more preferably, 0.4. If the water retention ratio is larger than 0.5, there are cases where rain water significantly inhibits the volatilization of the insecticide component volatile at normal temperature, to the extent that an intended insecticidal effect cannot be obtained. As used herein, the amount of water the structure can hold means that the amount of water physically adhered to the dents and/or gaps in the structure.

[0041] [Size of a single mesh]

The size of a single mesh refers to the size of a single mesh of the mesh portion of the structure, in other words, tire size of the surface area of one single mesh (the smallest mesh) surrounded by each of the resin filaments (the area surrounded by the center lines of the surrounding resin filaments), of the mesh portion of the structure, and it is preferably 10 mm2 or more, more preferably 20 mm2 or more. If the size of a single mesh is less than 10 mm2, the water adhered to the mesh is more likely to cover and fill the mesh hole due to the surface tension of water. As a result, the flow of air through the mesh is blocked, resulting in some cases a problem that the volatilization of the insecticide component is inhibited. On the other hand, the upper limit of the size of the surface area of a single mesh is preferably 200 mm2, and more preferably 150 mm2. The size of a single mesh greater than 200 mm2 reduces the strength of the mesh structure, making it susceptible to deformation. This leads not only to a poor handleability, but also to an insufficient surface area of the structure containing the insecticide component.

[0042] [Flying insect pest repellent perfume composition]

The chemical volatilizer of the present invention can contain a flying insect pest repellent perfume composition, in addition to the pyrethroid insecticide component volatile at room temperature, for the purpose of imparting perfume in the initial stage of the use of the chemical volatilizer, and reinforcing the insecticidal effect of the pyrethroid insecticide component volatile at room temperature.

[0043]

The above mentioned flying insect pest repellent perfume composition contains a flying insect pest repellent perfume, and preferably, a repellent effect-sustaining component.

[0044]

Examples of the flying insect pest repellent perfume include components containing one or more than one of perfume components (a) selected from acetic acid ester compounds represented by General Formula (I) and/or ally! ester compounds represented by General Formula (II) below, and one or more than one of perfume components (b) selected from monoterpene alcohols or aromatic alcohols having 10 carbon atoms,

(I) (wherein Ri represents an alcohol residue having from 6 to 12 carbon atoms,)

(II) (wherein, R- represents an alkyl group, alkoxy group, cycloalkyl group or cyeioalkoxy group having from 4 to 7 carbon atoms; or a phenoxy group) [0045]

Specific examples of the acetic acid ester compound represented by the above mentioned General Formula (I) include p-tert-hutylcyclohexyl acetate, o-tert-butyicyclohexyl acetate, p-tert-pentylcyclohexyl acetate, tricyclodecenyl acetate, benzyl acetate, phenyl ethyl acetate, styralyl acetate, anisyl acetate, cinnamyl acetate, terpinyi acetate, dihydroterpinvl acetate, linalyi acetate, ethyl linalyl acetate, dtronellyl acetate, geranyl acetate, neryl acetate, bomyl acetate, isobomyl acetate, and the like.

[0046]

Specific examples of the ally! ester compound represented by the above mentioned General Formula (II) include allyl hexanoate, ailyl heptanoate, ally! octanoate, ally! isobutyl oxyacetate, allyl n-amyloxyacetate, allyl cyclohexyl acetate, allyl cyclohexyl propionate, allyl cyclohexyl oxyacetate, allyl phenoxyaeetate and the like.

[0047]

Further, specific examples of the component (b) include terpincol, geraniol, dihydromyrcenol, homed, menthol, citronellol, nerol, linalool, ethyl linalool, thymol, eugenol, p-menthan-3,8-diol and the like.

[0048]

The content of the component (a) is preferably from 0.1 to 1.0 times the content of the component (b). It has been confirmed that the incorporation of the components (a) and (b) within this range contributes to a high repellent, effect against flying insect pest.

[0049]

As the flying insect pest repellent perfume, perfumes other than those mentioned above can he added as appropriate. Examples thereof include monotcrpene hydrocarbons such as iimonene; monoterpene ketones such as menthone, carvonc, pulegone, camphor and damascene; monoterpene aldehydes such as citral, citroneilal, neral, and perillaldehyde; ester compounds such as cinnamyl formate, and gerany! formate; phenyl ethyl alcohol; diphenyl oxide; indole aroma; and various types of essential oils containing the above mentioned perfume components, such as jasmine oil, neroli oil, peppermint oil, bergamot oil, orange oil, geranium oil, petitgrain oil, lemon oil, citronella oil, lemongrass oil, cinnamon oil, eucalyptus oil, lemon eucalyptus oil and thyme oil.

[0050]

It is preferred that one or more than one of glycol and/or glycol ether having a vapor pressure at 20°C of from 0.2 to 20 P be used as the repellent effect-sustaining component. Conventionally, glycol and/or glycol ether are considered as solvents, treated equally as Ethanol, iso-propanol, kerosene and the like, and their effects against flying insect pest have never been mentioned. However, the present inventors have found that the above mentioned glycol and/or glycol ether are not only capable of being used as a solvent, but also capable of specifically sustaining the repellent effect of the flying insect pest repellent perfume, and, when a fragrant flying insect pest repellent perfume is used, also capable of sustaining its initial note.

[0051]

Specific representative examples of the repellent effect-sustaining component include (the vapor pressure at 20°C is described in parentheses) propylene glycol (10.7 Pa), dipropylene glycol (1.3 Pa), tripropylene glycol (0.67 Pa), diethylene glycol (3 Pa), triethylene glycol (1 Pa), 1,3-butylene glycol, hexylene glycol (6.7 Pa), benzyl glycol (2.7 Pa), diethylene glycol monobutyl ether (3 Pa), dipropylene glycol monobutyl ether, and tripropylene glycol monomethyl ether. Among those, dipropylene glycol is preferred.

[0052]

The content of the repellent effect-sustaining component is preferably from 0.2 to 10 times the content of the flying insect pest repellent perfume. When these components are contained within this range, it has been proven that the effect of the flying insect pest repellent perfume can be sufficiently sustained.

[0053]

In cases where the flying insect pest repellent perfume composition is incorporated into the chemical volatilizer, an appropriate content of the perfume composition is about from 0.2 to 2 times the content of the pyrethroid insecticide component volatile at room temperature. Too small a content of the perfume composition results in a failure to impart perfume. On the other hand, too large a content may result in an excessively strong perfume, or may have an impact on the volatilization of the insecticide component, and thus it is not preferred.

[0054]

When the above mentioned flying insect pest repellent perfume composition is used, the flying insect pest repellent perfume composition may be incorporated during the preparation of the resin pellets containing the insecticide component. However, it is preferred that the resin pellets containing the insecticide component and the pellets containing the flying insect pest repellent perfume component be prepared individually in advance, followed by kneading both kinds of the pellets. This is because, the heating temperature used in the production of the pellets containing the flying insect pest repellent perfume component is from 90 to 130°C, and it is lower than the heating temperature used in the production of the resin pellets containing the insecticide component, which is from 110 to 140°C, and there is an advantage of reducing the loss of highly volatile perfume composition in preparing the respective kinds of pellets individually.

[0055] [Content of pyrethroid insecticide component volatile at room temperature]

The content of the pyrethroid insecticide component volatile at room temperature carried by the resin carrier of the chemical volatilizer is not particularly limited, since it varies depending on the type of the insecticide component to be used, usage environment, and usage conditions. However, it is preferred that the content be within the range of from 0.5 to 20% by mass, in order to secure the amount of the insecticide component necessary to exhibit the insecticidal effect, to facilitate the molding of the mixture into which the insecticide component has been kneaded, and in addition, to prevent the insecticide component from bleeding excessively to the surface of the resin carrier to cause stickiness.

[0056]

If the content of the insecticide component is less than 0.5 % by mass,.the amount of the insecticide component may not be sufficient to exhibit the intended insecticidal effect. On the other hand, if the content of the insecticide component is greater than 20% by mass, it complicates the molding of the mixture into which the insecticide component has been kneaded, and the insecticide component is more likely to bleed excessively to the surface of the resin carrier, thereby causing stickiness.

[0057]

An exemplary content of the pyrethroid insecticide component volatile at room temperature is from about 30 to 2000 mg for a use period of about 30 to 365 days.

[0058]

The content varies depending on the type of the insecticide component used. However, the least volatilization amount of the insecticide component necessary to provide an insecticidal effect, when metofluthrin alone is used as the insecticide component, for example, is 0.03 mg/hr or more; when profluthrin alone is used, it is 0.03 mg/hr or more; and when transfluthrin alone is used, it is 0.06 mg/hr or more. Therefore, the content of the pyrethroid insecticide component volatile at room temperature for the usage period of from 30 to 365 days can be determined with the range of: from 30 to 1000 mg in the case of metofluthrin; from 30 to 1000 mg in the case of profluthrin; and from 60 to 2000 mg in the case of transfluthrin.

[0059] [Other additives]

The chemical volatiiizer of the present invention may include the flying insect pest repellent perfume composition, as described above, particularly in order to impart perfume in the initial stage of the use, and to reinforce the insecticidal effect. In addition, the chemical volatiiizer may also contain a long-lasting perfume component having a boiling point within the range of from 250 to 400°C and capable of sustaining its aroma for a longer period of time.

In this case, it is possible to match the period of time during which an insecticidal effect is provided by the pyrethroid insecticide component volatile at room temperature, and the period of time during which a perfume effect is provided by the long-lasting perfume component, so that the dissipation of the insecticidal effect can be notified by the dissipation of the perfume effect. Examples of the long-lasting perfume component include galaxolide, musk ketone, hexyl cinnamic aldehyde, ethylene brassylate, methyl atralate, hexyl salicylate, tricyclodecenyl acetate, Granger Crystal, Ambroxan, eashmeran, caron, heliotropin, indole aroma, indole, methyl cedryl ketone, methyl β-naphthyl ketone, methyl dihydrojasmonate, rosephenone, 7-acetyl-l,2,3,4,5,6,7,8-octahydro-l,l,6,7-tetraniethylnaphthalene and the like.

[0060]

Further, synergists, repellents, antibacterial agents, fungicides, other functional components and the like can also be used in combination. Examples of the synergist include isobomyl thiocyanoacetate (brand name: IBTA), N-oetyl bicycloheptane carboxyimide (brand name: Cynepirin 222), N~(2-ethvlhexyl)-l-isopropyl-4-methylbicyclo[2,2,2]oct-5~ene~2,3-dicarboxyimide (brand name: Cynepirin 500) and the like.

[0061]

Examples of the repellent include N,N~diefhyl-m-toluamide (brand name: DEET), dimethyl phthalate, dibutyl phihalate, 2-ethyl-1,3-hexandioL l,4,4a,5a,6,9,9a,9b-oetahydrodibenzofi.iran-4a-carbaldehyde and the like.

[0062]

Examples of the antibacterial agent include hinokitiol, tetrahydrolinalool, eugenol, citronellal, allyl isothiocyanate and the like.

[0063]

Examples of the fungicide include isopropyl methylphenol, orthophenylphenol and the like.

[0064]

Examples of the other functional component include stress reducing components containing leaf alcohol and/or leaf aldehyde, referred to as “green note”.

[0065]

The chemical volatilizer may further contain coloring agents (coloring pigments), antistatic agents and the like, as appropriate. The commercial value of the chemical volatilizer can further be increased by imparting color, or by attaching a time indicator which allows visual confirmation of the expiration of the chemical volatilizer.

[0066]

Although all of the pyrethroid insecticide component volatile at room temperature used in the present invention have sufficient stability, stabilizers such as antioxidants can be added in order to further increase its stability. For example, 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 4,4’-methylenebis(2-methyl-6-i-butyl phenol), BHT, BHA, 3,5-di-t-butyl-4-hydroxyanisole, mercaptobenzimidazole and the like can be used.

[0067]

In addition, ultraviolet absorbers such as para-aminobenzoic acids, cinnamic acids, salicylic acids, benzophenones and benzotriazoles can be used as agents for inhibiting the ultraviolet absorption, to further increase the light resistance of the chemical volatilizer during the use and storage.

[0068] [Container]

In the present invention, the chemical volatilizer is placed in a plastic container for use. The shape and the size of the plastic container for the chemical volatilizer are not particularly limited, as long as the container allows for a stable volatilization of the pyrethroid insecticide component volatile at room temperature. However, it is preferred that the ratio of the area of openings of the container relative to the total surface area of the container (open area ratio) be from 10 to 50%, in terms of volatilization efficiency.

[0069]

The openings may be provided not only on the front surface and the rear surface, but also on the side surfaces, top surface, and the bottom surface, as long as the open area ratio is within the above mentioned range. It is preferred to provide openings also on the side surfaces, because the efficiency of the air flow in the container can be improved. The shape of the openings is not particularly limited.

[0070]

Further, the shape of the plastic container is not particularly limited. If the resin carrier is in the shape of a cylinder, the container may also be formed cylindrical corresponding to the shape of the resin carrier. In cases where the chemical volatilizer is adapted for attaching to an air cleaner, for example, the container may be simplified as appropriate, just enough to hold the resin carrier.

[0071]

Examples of the plastic container include a container formed by assembling plastic members in the shape of folded planar sheets, a container formed as an integrated molded article of plastic, and the like.

[0072]

In the above mentioned container formed by assembling plastic members in the shape of folded planar sheets, two of the folded members are used in a pair, and they are assembled such that each of the bent faces of one folded member overlaps with each of the bent faces of another folded member.

[0073]

Further, a tongue portion with a cut can be provided at the end portion of the bent face of the folded member, and a hook portion can he provided to extend such that it can be folded to stand up. In this case, a window into which the above mentioned hook portion can be folded can be provided on the upper area of the rear surface. This allows the chemical volatilizer to be used in various types of applications.

[0074]

In other words, if the tip portion of the hook portion described above is engaged, for example, with the portion of the upper surface of the container, problems such as the container being blown away by the wind when used outdoors, or the suspended container falling down by mistake when used indoors can be prevented. This allows the chemical volatilizer to exhibit a satisfactory effect in a desired place of use.

[0075]

On the other hand, the container formed as an integrated molded article of plastic can be produced by any ordinary molding method such as injection molding or vacuum molding. However, its production process can be further simplified, if the container is configured such that the top and bottom surfaces, and the front and the rear surfaces thereof are joined together with hinges, or by fitting. In this case, if a hook portion which can he stood up is provided on the upper surface of the container, the chemical volatilizer can he used more efficiently.

[0076]

As in the case mentioned above, if the tip portion of the above described hook portion is configured so as to be engaged with a portion of the container, for example, an opening or a recess provided on the top surface, problems such as the container being blown away by the wind when used outdoors, or the suspended container falling down by mistake when used indoors can be prevented, thereby allowing the chemical volatilizer to exhibit a satisfactory7 effect in a desired place of use.

[0077]

The portion of the container with which the hook portion is engaged can be determined as appropriate upon its production. However, it is preferred that the hook portion be engaged with a portion of the container on the same surface as the hook portion is provided, because it allows to prevent the container from moving from its installed position.

[0078]

Examples of materials which can be used to produce the plastic member in the form of planar sheet or the integrated plastic molded article include: polyethylene terephthalate, polyethylene, polypropylene, polybutylene terephthalate, Nylon, polyamide and the like. However, it is preferred that polyethylene terephthalate (PET) or polybutylene terephthalate (PBT) be used, in view of the strength and properties of the container.

[0079]

The thickness of the plastic member or the plastic molded article is preferably from 0.05 to 2 mm, in terms of its relationship with the shape of the resin carrier and with the capability of the resin carrier to allow volatilization of the insecticide component, and in terms of economic efficiency. However, those of various thicknesses can be used.

[0080] [Packaging bag]

In general, the chemical volaiilizer of the present invention is commercially marketed after being placed in a container and then packaged in a chemical-impermeable film bag, which can be opened upon use. Alternatively, the chemical volaiilizer alone can be packaged in a chemical-impermeable film bag and marketed, so that the chemical volatilizer can be taken out from the bag and set into a container upon use. Examples of materials for the chemical-impermeable film bag include polyester (such as PET and PBT), polyamide, polyacetal, polyacrylonitrile and the like. The thickness of the film bag is determined within a range in which the flexibility of the bag is not compromised. In addition, the inner surface of the chemical-impermeable film bag can be laminated with a polyethylene film, polypropylene film or the like, in order to impart heat-sealing properties.

[0081] [Applications]

The chemical volatilizer prepared according to the present invention provides an excellent insecticidal effect against mosquitos such as Cuiex pipiens, Culex pipiens molestus, and Aedes albopictus; black flies, midges, flies sandflies, clothes moths and the like, for a predetermined period of time corresponding to its design specification, from immediately after the start of use to over approximately 365 days. The chemical volatilizer can be used inside the room, for example, in a living room, Japanese-style room, and entrance; in a warehouse; a restaurant; the interior or entrance of a .factory'' or workshop; a cattle shed such as a poultry house and a pig house; a pet house such as a dog kennel and a rabbit hutch, or the vicinity thereof; the interior of a septic tank or a manhole; the interior or entrance of a tent used in camping and the like; or at a site of outdoor activities such as barbecuing, fishing and gardening, or the vicinity thereof. If the chemical volatilizer is used, for example, hung from a curtain rail or a laundry pole by its hook portion at a place near a window or around a porch, which separates the interior and the exterior of the room, the entry of insect pests from the outside to the inside of the house can be prevented, and therefore, it is extremely practical.

[0082]

In addition, the chemical volatilizer can be formed in the shape of a cylinder to be attached to a lead for a pet dog, or its container may be simplified as appropriate to be attached to an air cleaner or the like.

[0083] [Feature of chemical volatilizer]

By having the above mentioned constitutions, it is possible to produce the chemical volatilizer of the present invention in a stable quality.

EXAMPLES

[0084]

The chemical volatilizer of the present invention will now be described with reference to Examples. It is to be understood that the purpose of the Examples described below is to merely present examples embodying the present invention and it is in no way limiting the technical scope of the present invention.

First, the chemicals and materials used, and die methods of evaluating the performance of the chemical volatilizer will be described.

[0085] <Chemicals and materials used>

Metofluthrin (Eminence; manufactured by Sumitomo Chemical Company, Limited) • Transfluthrin (Biothrin; manufactured by Sumitomo Chemical Company, Limited)

Profluthrin (Fairytale; manufactured by Sumitomo Chemical Company, Limited) - Microcrystalline silica (Carplex #80; manufactured by Evonik Industries; white carbon, average particle diameter: 15 pm; hereinafter referred to as “silica”) • Ethylene-vinyl acetate copolymer (Uitracen 710; manufactured by Tosoh Corporation; the ratio of ethylene units: vinyl acetate units = 72 : 28; hereinafter referred to as “EVA”) • Low density polyethylene (Suntec LDM652Q; manufactured by Asahi Kasei Corporation; hereinafter referred to as “LDPE-A”)

Low density polyethylene (Novatec LDLJS02; manufactured by Japan Polyethylene Corporation; hereinafter referred to as “LDPE-B”) • Polyethylene terephthalate (Bellpet IP 12IB; manufactured by Bell Polyester Products, Inc.; hereinafter referred to as “PET”) [0086] <Measuremeni of water retention ratio>

The obtained chemical volatilizer was immersed in water for 3 minutes and pulled up slowly, and its water retention ratio was calculated according to the equation below: water retention ratio = (weight of water attached to the chemical volatilizer) / (weight of the chemical volatilizer), [0087] <Measurement of the amounts of chemical volatilized before and after the water retention ratio test>

The obtained chemical volatilizer was allowed to volatilize for 1 day in a room controlled at 25°C, with wind blowing at a wind velocity of 1 m/sec, and the amount of the active ingredient contained in the chemical volatilizer was measured by gas chromatography. Then the amount of the chemical volatilized was calculated.

Further, immediately after performing the above mentioned water retention ratio measurement test, the chemical volatilizer was allowed to volatilize for 2 days under the same conditions. The amount of the chemical volatilized for 2 days was then calculated, and the obtained value was converted to the amount per 1 day. The amounts of the chemical volatilized before and after the water retention ratio test were compared to investigate the relationship between the amount of the chemical volatilized and the water retention ratio.

[0088] (Examples 1 to 5, 7 to 9 and Comparative Example 1) <Method for producing resin pellets>

In each of Examples and Comparative Example, 10 parts by weight of the pyrethroid insecticide component volatile at room temperature shown in Table 1 was heated to 50°C to be carried by 6 parts by weight of silica. Each of the resultant was then kneaded with 40 parts by weight of EVA and 44 parts by weight of LDPE-A, and subjected to an extrusion molding at a temperature of from 120 to 140°C, using a twin-screw extruder manufactured by Technovel Corporation, to obtain resin pellets containing the pyrethroid insecticide component volatile at room temperature, having a diameter of 3 mm and a length of 5 mm.

[0089] <Production of molded article>

One hundred parts by weight of each of the resulting resin pellets containing the pyrethroid insecticide component volatile at room temperature, and 300 parts by weight of LDPE-B (including 10 parts by weight of colorant pellets) were kneaded at a temperature of from 120 to 140°C, and each of the kneaded mixture was charged into an injection molding machine or an extruder, to obtain a chemical volatilizer composed of a planar net (in Examples 7 to 9) shown in FIG. 1, and a chemical volatilizer composed of a three-dimensional structure (Examples 1 to 5 and Comparative Example 1) shown in FIG. 2.

The weight, size and the area of the smallest single mesh of the respective chemical volatilizers are shown in Table 1.

According to the above mentioned method, the water retention ratio and the amounts of the chemical volatilized before and after the water retention ratio test, of the thus obtained chemical volatilizers were measured. The results are shown in Table 1.

[0090] [Table 1]

[0091] (Example 6, Comparative Examples 2 and 3) in each of the Examples and Comparative Examples, a three-dimensional structure (knitted fabric) was prepared in the sizes shown in Table I as follows. Two pieces of plain textures, which serve as chemical impregnation members, were formed using PET textured yams, and these structures were then bound together with twisted filaments to obtain a three-dimensional structure.

The weight, size and the area of the smallest single mesh of the respective three- dimensional structures are shown in Table 1.

Each of the pyrethroid insecticide component volatile at room temperature in an amount shown in Table 1 ’was dissolved in 0.25 g of acetone, respectively, to prepare a chemical solution, wliich is then carried by each of the three-dimensional structures obtained above. According to the above mentioned method, the water retention ratio and the amounts of the chemical volatilized before and after the w'ater retention ratio test, of the thus obtained chemical volatilizers were measured. The results are shown in Table 1.

[0092] T he test results revealed that, in the chemical volatilizers of the Examples of the present invention having a water retention ratio within a range of 0.005 or more and 0.5 or less, the degree of reduction in the volatilization amount of the insecticide component was small even immediately after the water retention ratio test, demonstrating that the influence of rain on the volatility of the insecticide component due to adhesion of rain 'water is small. As can be seen from the test results of Example 4 and Example 6, when a three-dimensional structure whose area of a single mesh is small or a structure composed of twisted filaments is used, the water retention ratio tends to be higher.

In contrast, in the chemical volatilizers of Comparative Examples 1 to 3 having a w’ater retention ratio of greater than 0.5, the amount of the chemical volatilized immediately after the water retention ratio test was inhibited significantly, suggesting the possibility that the insecticidal effect is reduced.

INDUSTRIAL APPLICABILITY

[0093]

The present invention can be widely used in the field of insect pest control in which a chemical volatilizer is used.

DESCRIPTION OF SYMBOLS

[0094] 1 Planar net 2 Three-dimensional structure 21 Rectangular corrugated member 21a First apex 21b Second apex 22 Reinforcing member [0095]

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

[0096]

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

Claims

1. A chemical voiatiiizer composed of a structure comprising a mesh made of a fibrous product containing a pyrethroid insecticide component volatile at room temperature; characterized in that the fibrous product is composed of resin filaments, and a water retention ratio of the structure, which is a ratio of an amount of water the structure can hold relative to the weight of the structure, is 0.005 or more and 0.5 or less.

2. The chemical voiatiiizer according to claim 1, wherein a size of a single mesh in a mesh portion of the structure is 10 mm2 or more and 200 mm‘ or less.

3. The chemical voiatiiizer according to claim 1 or 2, wherein the resin filaments are obtained by kneading the pyrethroid insecticide component volatile at room temperature into a resin carrier and then by molding a resulting kneaded mixture.