JPH02234628A - Liquid-absorbing core and transpiration method of drug - Google Patents

Abstract

PURPOSE:To stabilize volatilizing amount by providing porous liquid-absorbing and transpiration layer around supporting material. CONSTITUTION:A porous liquid-absorbing layer of bag-like or tube-like made of cloth, non-woven fabric or felt, etc., of natural, artificial or inorganic fiber is provided around cylindrical supporting material made of PE, PP, china and porcelain or wood, etc., to obtain a liquid-absorbing core 7. Next, a vessel 1 including drug solution 2 is installed in containing vessel 3 and said liquid- absorbing core 7 is dipped in drug solution 2 through drug solution-injecting port 6, then the drug solution is absorbed, thus an electric current is sent to a heating element 4 to heat the liquid-absorbing core 7 to transpire the drug solution 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application in Industry] The present invention relates to a liquid absorbent wick used in a suction type heating evaporation device and a method for dispersing chemicals.

[Conventional technology]

BACKGROUND ART Traditionally, methods of heating and evaporating chemicals for the purpose of killing insects, such as (1) so-called mosquito coils and (2) electric mosquito repellent mats, have been popular. In recent years, a method has been developed in which a porous liquid-absorbent core is immersed in a drug solution and the upper part of the core is heated to heat and evaporate the drug (
The liquid method (hereinafter referred to as "liquid method") has once again attracted attention because it does not need to be replaced every time and its effects are stable over a long period of time. This method has been known for a long time, and for example, a method using direct heating is described in Utility Model Publication No. 1, Publication No. 43-2508.However, direct heating causes severe decomposition of the drug, so indirect heating is generally used. There is a tendency for this method to be adopted. As a method using indirect heating, a method of interposing felt or the like between the liquid absorbing wick and the heating element is disclosed in Utility Model Publication No. 36-12459 and Utility Model Publication No. 46-22.
It is described in Japanese Utility Model Publication No. 585, and methods of heating the liquid absorbent wick and heating element by separating them at regular intervals are disclosed in Japanese Utility Model Publication No. 43-26274, Japanese Utility Model Publication No. 44-8361, and Japanese Utility Model Publication No. 45-14.
It is described in Japanese Utility Model Publication No. 913 and Japanese Utility Model Publication No. 45-292445.

However, the products at that time had problems with long-term sustainability due to clogging of the resin, etc., and in the end, their advantages were not recognized compared to the mosquito repellent mats and mosquito coils, and they were not accepted by the market. It ended in

In recent years, this liquid type mosquito repellent has been re-recognized because
This is due not only to changes in lifestyle consciousness and the living environment due to improved lifestyles, but also to technological advances in heating elements, the development of insecticidal ingredients that are effective in small amounts, improvements in the quality of pharmaceutical raw materials including active ingredients, and advances in plastic processing technology. it is conceivable that.

[Problem to be solved by the invention]

In the past, felt was used as the porous liquid-absorbing core used in these liquid-type heating evaporators, but in the case of felt, the amount of liquid absorbed is generally too large, or the chemical solution is absorbed by the core during storage, transportation, and use. There are problems such as overflowing through the core, or difficulty setting the lead correctly due to its flexibility.

In recent years, liquid-absorbing cores made of inorganic powder or inorganic powder and wood flour, etc. fixed and molded with water-soluble glue have been published in Japanese Patent Publication No. 6123163, Japanese Patent Publication No. 59-40409, Japanese Patent Application Laid-Open No. 63-24841, Japanese Patent Publication No. 63-24841, Publication No. 63-63330, No. 63-74440
We discovered a liquid-absorbent wick that was fixed as shown in the publication, and filed a patent application (Japanese Patent Application No. 328526/1983). However, these liquid-absorbent cores are very time-consuming to manufacture, have many technical difficulties (drying, dimensional stability, reproducibility of performance, etc.), and have limited shapes. There is a point. In addition, water-soluble sizing agents such as starch and CMC-Na are often used for these liquid-absorbing cores because they are advantageous in manufacturing, but even in this case, if the chemical solution is an aqueous solution, it is natural that the sizing agent The problem remains that physical deterioration of the liquid absorbent core occurs due to dissolution, elution, and swelling, making it unusable.

[Means to solve the problem]

The inventors of the present invention have carried out extensive studies and found that a liquid absorbent core with a structure in which cloth, non-woven fabric, etc. is provided around a holding material such as plastic or metal is easy to make, the amount of volatilization is stable, and it can be adjusted. It has also been found that it is easy to use and can be used without particular problems even in the case of an aqueous solution of the drug.

That is, the present invention provides a liquid absorbent core having a structure including a holding material at the center and a porous liquid absorbent evaporation layer around the periphery.

Furthermore, a liquid-type drug heating evaporation method using the liquid-absorbing core is provided. Preferably, a pyrethroid is used as the drug, and the drug is evaporated by heating and used for the purpose of controlling pests such as mosquitoes and flies. Further, the solution containing the drug may be an aqueous solution.

In the present invention, the holding material is columnar, preferably cylindrical, having sufficient mechanical strength, and the material is such that it does not come into contact with the chemical solution.
It is selected from those that do not undergo physical or chemical deterioration even when immersed and have sufficient heat resistance at temperatures that volatilize the chemical. For example, plastics such as polyethylene, polypropylene, and polyvinyl chloride, copper, brass, iron, stainless steel,
It is an aggregate of fibers or powder that is stable against chemical liquids and does not decompose in metals such as aluminum, ceramics, wood, and temperature, and absorbs chemical liquids by capillary action.

Specifically, they include cloth, paper, nonwoven fabric, felt, etc. made of various natural fibers, artificial fibers, and inorganic fibers. A liquid absorbent core can be created by wrapping, pasting, or coating such a porous liquid absorbing evaporation layer around a holding material, or by covering it in the form of a bag, or by forming it into a tube and passing it through the holding material. . Alternatively, thin pieces of wood, bamboo, plant leaves, bark, etc. may be similarly wrapped or pasted.

If necessary, the chemical liquid immersion portion of the liquid absorbent core may be replaced with another structure.

The volatilization rate of the chemical solution changes depending on the heating temperature and the composition of the chemical solution, but in the liquid-absorbing core of the present invention, it can be adjusted as appropriate by changing the material, outer diameter, thickness, etc. of the liquid-absorbing evaporation layer.

The liquid-absorbent core of the present invention can be colored with carbon black or other pigments, if necessary.

Further, anti-mildew, antiseptic, insect repellent, flame retardant, degreasing, and other treatments may be applied.

The liquid-absorbing core of the present invention is intended for insecticidal, sterilizing, fragrance, etc.
It can be suitably used as a liquid-absorbing core of a liquid-type heating evaporation device that heats and scatters chemicals such as various insecticides, bactericides, deodorants, and fragrances.

An example of a device suitable for using the liquid absorbent wick of the invention is shown in the drawings. In the figure, ■ is a container containing the chemical solution 2, and the container 1
is detachably stored and held in the storage container 3. The upper part of the storage container 3 is open, and a ring-shaped (
Alternatively, a pair of semi-annular heating elements 4 are fixedly attached.

5 is a cord connected to the heating element 4. A liquid medicine inlet 6 is provided in one part of the container 1 , and a liquid absorption wick 7 is placed in the liquid medicine inlet 6 such that a part thereof is disposed in the center of the annular heating element 4 . , is held in a substantially sealed shape. What is illustrated is an example of a device suitable for using the liquid absorbent wick of the present invention, but it goes without saying that the device is not limited to this, and devices of various shapes can be used.

As the chemical liquid stored in the container 1, an insecticidal liquid, an aromatic liquid, etc. are used depending on the purpose. When the above device is used as a heating transpiration insecticidal device, put the insecticidal liquid into the container l,
The heating element 4 is energized to heat the liquid-absorbing core 7 so that the surface temperature thereof is preferably 70 to 140°C depending on the type of insecticide. If the heating temperature is too high, there is a problem that thermal decomposition and polymerization of the drug tend to occur, resulting in a decrease in the amount of volatile active ingredients.
This is also undesirable since the high-purity point substances produced as a result tend to accumulate in the liquid absorbent wick and cause the wick to become clogged. Furthermore, if the heating temperature is too low, volatilization will naturally be delayed, and in some cases, only the solvent will be volatilized, and the volatilization of the active ingredient may be hindered.

Therefore, the optimum temperature is selected depending on the type and concentration of the active ingredient, the volatility of the solvent, etc.

As the above-mentioned killing liquid, a solution in which an insecticide is dissolved in various solvents is used. Preferably, the solvent has a high flash point, is odorless, and is toxicologically safe. The boiling point of the solvent used is 150 to 3, depending on the heating temperature of the liquid absorbent core.
Those falling within the range of 50'C are preferred. Those satisfying these conditions include saturated aliphatic or alicyclic hydrocarbons having 12 or more carbon atoms, which are industrially available as normal paraffins, isoparaffins, or naphthenic hydrocarbons. In addition, as an aromatic hydrocarbon, phenylxylylethane or the like can be used as an odorless solvent. Of course, the solvent is not limited to these hydrocarbons as long as it satisfies the above conditions. For example, various nonionic surfactants, preferably polyoxyalkylene alkyl ether-based solubilizers (refers to those that can stabilize insecticidal ingredients in a clear state in water, regardless of the presence or absence of micelle formation), and ordinary surfactants. (In addition, it also contains solvents that are compatible with water and oil.) to form an aqueous insecticidal liquid,
It can also solve the flammability problem.

As the insecticide used in the present invention, various conventionally used volatile insecticides can be used, including pyrethroy F insecticides, carbamate insecticides, organophosphorus insecticides, and the like. Generally, pyrethroid insecticides are preferably used because of their high safety, and examples thereof include the following insecticides.

(a) 3-aryl-2-methylcyclopent-2-en-4-one-1-yl d Bunichi cis/trans-chrysanthemate (generic name allethrin; trade name pinamine; manufactured by Sumitomo Chemical Co., Ltd.) (b ) 3-aryl-2-methylcyclopent-2-en-4-one-1-yl d-cis/
Trans-chrysanthemate (trade name: Pinamine Forte, manufactured by Sumitomo Chemical Co., Ltd., hereinafter abbreviated as insecticide A) (c) d-3-aryl-2-methylcyclopenta-2-
En-4-one-1-yl d-1 lansu chrysanthemate (trade name Kislin: manufactured by Sumitomo Chemical Co., Ltd.) (d) 3-aryl-2-methylcyclopenta2-2-4-one-1- yl d-}lan chrysanthemate (generic name: paioallethrin) (e) 2-methyl-4-3-(2-provinyl)cyclopent-2-enyl chrysanthemate (f) (S) -2- Methyl-4-oxo 3 (2-7
'lopinyl) cyclopent-2-enyl d-cis/trans-chrysanthemate (generic name bralesthrin, hereinafter abbreviated as insecticide B) Cg) N- (3,4,5.6-tetrahydro'phthalimido)methyl dl- Cis/trans-chrysanthemate (generic name phthalthrin; trade name neopinamine; manufactured by Sumitomo Chemical Co., Ltd.) (h) 3-phenoxybenzyl 2-(4-ethoxyphenyl)-2-
methyl propyl ether) l. yc-IQ name: etofenbrox) (i) 5-benzyl-3-furylmethyl
d-cis/trans-chrysanthemate (generic name: Renumethrin; trade name: Crysuronforte; manufactured by Sumitomo Chemical Co., Ltd., hereinafter abbreviated as Insecticide C) (j) 5-propalkyl-2-furylmethyl chrysanthemate (general name) (k) 5-probargyl-2-furylmethyl d-cis/trans-chrysanthemate (trade name: Pinamin D Forte: manufactured by Sumitomo Chemical Co., Ltd., hereinafter abbreviated as insecticide D) (1) 3 -phenoxybenzyl 2,2-dimethyl-3
-(2,2-dichlorovinyl)cyclopropane lupoxylate (generic name: vermethrin; trade name: kusumin:
(manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as Insecticide E) (m) 3-phenoxybenzyl d-cis/trans-chrysanthemate (generic name: Phenothrin; trade name: Sumitrin: manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as Insecticide E) (abbreviated as Insecticide F) (n) α-cyano 3-7 enoxybenzyl 12 α isop, lobi-4-chlorophenylacetate (generic name: Phen/Hirarelate (trade name: Sumicidine, manufactured by Sumitomo Chemical Co., Ltd.) (o) ( S) Mono-alpha-cyano-3-phenoxybenzyl
(S) -α-Improvyl-4-chlorophenylacetate (general name: sphenvalerate) (p) (S) -α-cyano-3-phenoxybenzyl (
IR, 3R) -3-(2,2-dichlorovinyl)-2
．． 2-dimethylcyclopropane rupoxylate (q) (RS) -α-cyano-3-phenoxypenzyl (IRs) -cis/trans-3(2,2-dichlorovinyl)-2,2-dimethylcyclopropane rupoxylate ( Generic name Cypermethrin) (r) α-Cyano 3-phenoxybenzyl d-cis/trans-chrysanthemate (Generic name Cyphenothrin) (S) α-Cyano 3-phenoxybenzyl 2,2
,3.3-Tetramethylcyclopropane lupoxylate (generic name: phenprobatrin) (t)((pentafluorophenyl)monomethyl)(IR
,3R)-3-(2,2-dichlorohydryl)-2
．． 2-dimethylcyclopropane lupoxylate (generic name: fenfluthrin) (u) 1-ethynyl-2-
Methyl-2-pentekol d-cis/trans-chrysanthemate (generic name empenthrin, hereinafter abbreviated as insecticide G) (v) 3-aryl-2-methyl-cyclopent-2-en-4-on-eryl 223, 3-tetramethylcyclopropaneylpoxyle}(-1[telarethrin) (W) 1-ethynyl-2-methyl-2-pentenyl 2
, 2,3.3-tetramethylcyclopropaneylpoxylate) (x)■-ethynyl-2-methyl-2-bentenyl 2
．． 2-dimethyl-3-(2,2-dichlorovinyl)cyclopropane 1-(Y)N- (3,4,
(Z) Dimethyl 4-tech1 xyphenyl) {3(3-
phenoxy-4-fluorophenyl)probyl}silane Among these, insecticides A to H are preferred in terms of industrial availability, economic efficiency, efficacy, and safety, and insecticide D is particularly preferred.
is superior in terms of effectiveness/economical efficiency.

The concentration of the effective insecticidal component in the insecticidal liquid is preferably 0.5% by weight or more and 20% by weight or less, preferably 0.5% by weight or more and 20% by weight or less.
Used at concentrations ranging from 5 to 8% by weight.

These insecticides may be used alone or in combination.

Further, if necessary, a small amount of stabilizers, deodorants, synergists, pigments, and other auxiliary agents may be added to the chemical solution.

Similarly, when used for the purpose of fragrance, various natural and artificial fragrances can be used, such as animal and vegetable natural fragrances, hydrocarbons, alcohols, phenols, aldehydes, ketones, lactones, These include artificial fragrances such as oxides and esters, and one type of these can be used alone, or two or more types can be used in combination. Furthermore, depending on the purpose, various chemicals such as deodorants, disinfectants, and repellents can be used as long as they are volatilized by heating. The concentration of these various drugs is 0.5~
10% by weight is preferred.

〔Example〕

The present invention will be explained in more detail below using specific examples, but the present invention is not limited thereto.

In addition, in the following Examples and Comparative Examples, oil absorption amount refers to core 1
It is the weight (g) of normal paraffin absorbed per cc, and the oil absorption rate is defined as the absorbent core is cut into 70 mm, the lower 15 mm of which is immersed in the normal paraffin at room temperature, and the normal paraffin reaches the top of the core. It says time.

Further, unless otherwise specified, normal paraffin refers to a fraction having 14 to 16 carbon atoms.

Further, the water absorption amount and water absorption rate were measured in the same manner for an aqueous solution containing 40% by weight of a solubilizer (diethylene oxybutyl ether).

Examples 1 to 4 A cylindrical Teflon rod with a diameter of 6 mm and a length of 70 mm was wrapped with cloth (trade name: Microstar, manufactured by Teijin ■) or a silicone glass tube to form a liquid-absorbing core according to the invention. The oil absorption amount and oil absorption rate or water absorption amount and water absorption rate of :k'r Dδ and π were as shown in Table 1.

Table 1 Comparative Example 1 100 parts of diatomaceous earth, wood powder (K100 manufactured by Casino Co., Ltd.) 4
8 parts, activated carbon (Shirasagi C manufactured by Takeda Pharmaceutical Co., Ltd.) 12 parts, α
- 274 parts of water were added to 40 parts of starch and kneaded, and this was extruded and air-dried to obtain a liquid absorbent core having the same dimensions as above. Oil absorption amount is 0.33 g/cc, oil absorption rate is 8
It was time.

Comparative Example 2 Similarly, 40 parts of diatomaceous earth, 100 parts of clay, 16 parts of plaster
Part 0, CMC-NaB part, Sumilizer BP-76 (
A liquid absorbent core having the same dimensions as above was prepared from 0.92 parts of antioxidant (manufactured by Sumitomo Chemical Co., Ltd.). Oil absorption speed is 9
The oil absorption amount was 0.32 g/cc.

Volatilization test example 1 The liquid absorbent core obtained in Examples 1 to 3 was placed in the heating evaporator shown in the drawing,
A commercially available liquid-absorbing wick (made by washing the chemical solution with hexane and drying it, manufactured by Earth Pharmaceutical Co., Ltd.) and the liquid-absorbing wick obtained in Comparative Example 1.2 were set, and 1.8% insecticide D and BI were added.
Chemical solution 35 in which 1% T is dissolved in water containing 40% by weight of normal paraffin or diethylene oxybutyl ether
g and heated the side surface of the core to 120°C to conduct a volatilization test. In addition, if the chemical solution was insufficient by the predetermined heating time, only a new chemical solution was replenished at that point. In the volatilization test, (1) the amount of chemical solution decreased per hour and (2) the amount of insecticide volatilized per hour were investigated.

In (2), the insecticide was trapped with a silica gel packing force ram at regular intervals, the insecticide was extracted with acetone, and analyzed with a gas chromatogram.

The results are shown in Table 2.

Table 2 l9 [Effects of the Invention] As explained in detail below, the liquid absorbent wick of the present invention is very easy to manufacture, and is superior to conventional ones in terms of structure and performance. The amount of volatilization is stable and easy to adjust.

Therefore, the drug evaporation method of the present invention using this liquid-absorbing wick also has an effect superior to the conventional method, and in particular, it can be carried out without physical deterioration of the liquid-absorbing wick even when the drug is an aqueous solution. .

[Brief explanation of drawings]

The drawing is a longitudinal sectional view of an embodiment of an apparatus suitable for carrying out the method of the invention. In the diagram, 1... Container 2... Chemical solution 3...
... Storage container 4 ... Heating element 5 ...
...Code 6...Medical solution inlet 7...
...Liquid-absorbing core procedural amendment April 14, 1989 Patent Application No. 57180, 1999 2. Name of the invention Liquid absorbent wick and drug evaporation method 3. Relationship with the case of a person who cheats on amendments Name of patent applicant Title Dainichi Jomugiku Co., Ltd. 4. Agent address: 1-6 Ochanomizu Square Building B, Kanda Surugadai, Chiyoda-ku, Tokyo 6. A column for the detailed description of the invention in the specification to be amended is also good. Add the following information to the next Q. ``Glass tubes and artificial fiber tubes are particularly preferred materials.Glass tubes include those made by applying glass fiber to a k.B machine to create a braided diboob, and then simply heat-treated, or heat-insulated. There are some types that are coated with fest, silicone fest, etc. and dried to impart properties, and the diameter can be selected arbitrarily.The ability to absorb chemical liquids depends on the size of the gaps between the fibers, their density, etc. In addition to the surface area, it depends on the material of the coating film, but for the liquid absorption transpiration layer of the present invention, the diameter is φ
A tube with a diameter of about 4 to 7 mm and a small amount of varnish, or a thermoformed tube is more suitable. Further, as the artificial fiber tube, for example, a polyester fiber tube can be mentioned, which has the advantage of being more flexible than a glass tube. "that's all

Claims (4)

[Claims] (1) A liquid-absorbing core with a structure having a holding material in the center and a porous liquid-absorbing evaporation layer around the periphery. (2) In a transpiration method in which a solution containing a drug is absorbed into a liquid absorbent core and the liquid absorbent core is heated to evaporate the drug, the liquid absorbent core is the liquid absorbent core according to claim 1. Characteristic drug evaporation method. (3) The method for evaporating a chemical according to claim 2, wherein the solution is an aqueous solution. (4) The method for evaporating a drug according to claim 2 or 3, wherein the drug is a pyrethroid.