JP2604224B2 - Liquid absorption wick and chemical evaporation method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquid absorbent core used in a wicking type heating and evaporating apparatus and a method for evaporating a medicine.

[Prior Art] Conventionally, (1) a so-called mosquito coil and (2) an electric mosquito mat have been favored as a method of heating and evaporating a drug for the purpose of insecticide and the like. In recent years, the method of immersing a porous absorbent core in a drug solution and heating the core to heat and evaporate the drug (hereinafter referred to as the liquid method) does not need to be replaced each time, and the effect is stable for a long time. It has been drawing attention again for such reasons. This method has been known for a long time, and for example, Japanese Utility Model Publication No. 43-25081 describes a method using direct heating. Method tends to be adopted. As a method by indirect heating, a method of heating by interposing a felt or the like between a liquid absorbent core and a heating element is described in Japanese Utility Model Publication No. Sho 36-12449 and Japanese Utility Model Publication No. Sho 46-22585, The method of heating the heating element at a constant interval is described in Japanese Utility Model Publication No. 43-26274, Japanese Utility Model Publication No. 44-8361, Japanese Utility Model No. 45-14913, and Japanese Utility Model Publication No. 45-292445. I have.

However, at this time, clogging of resin etc.,
There are difficulties in long-term sustainability, etc.
Compared to mosquito coils, their advantages were unrecognized and unacceptable to the market.

In recent years, this liquid-type mosquito catcher has been re-recognized because, in addition to changes in living consciousness and living environment accompanying the improvement of life, technological advances in heating elements and the development of small and effective insecticidal ingredients It is thought to be due to the improvement in quality of drug raw materials including active ingredients and the progress of plastic processing technology.

[Problems to be solved by the invention]

By the way, felt was once used as a porous liquid absorbent core used in these liquid type heating and evaporators,
In the case of felt, there are generally problems such as too much liquid absorption, overflow of the drug solution through the core during storage, transportation and use, or difficulty in setting the core correctly due to its flexibility.

In recent years, an absorbent core formed by fixing inorganic powder or inorganic powder and wood powder with a water-soluble glue has been disclosed in JP-B-61-23163 and JP-B-61-23163.
These are disclosed in JP-A-63-24841, JP-A-63-63330, and JP-A-63-74440. The present inventors have also found calcium carbonate or magnesia or a liquid-absorbent core obtained by fixing organic powder to the same with an adhesive, and have previously filed a patent application (Japanese Patent Application No. 63-328526).

However, these liquid absorbent cores are very laborious to manufacture and have many technical difficulties (drying, dimensional stability, reproducibility of performance, etc.), and problems such as limited shape. There is a point. These liquid absorbent cores are made of starch, CMC-Na
Water-soluble pastes are often used because they are advantageous in production, but in this case, when the drug solution is an aqueous solution, of course, physical degradation of the absorbent core due to dissolution, elution, and swelling of the paste The problem remains that it does not stand use because it occurs.

[Means for solving the problem]

Although the present inventors have conducted intensive studies, they have surprisingly found that a liquid absorbent core obtained by merely cutting wood and bamboo can be used as the liquid absorbent core for the present liquid heating evaporator.

Japanese Patent Publication No. 59-40409 discloses that, for fibrous materials such as pulp and wood flour commonly used in electric mosquito traps, the materials are smoked by heating for a long time, and the subsequent absorption of the drug solution and This makes it difficult to evaporate, "(hereinafter abbreviated), and it was completely unpredictable from now on.

The present invention provides an absorbent core made of wood or bamboo, and a liquid chemical heating and evaporating method using the absorbent core. Preferably, pyrethroid is used as an agent, and the agent is heated and evaporated, and used for controlling pests such as mosquitoes and flies. or,
Preferably, the solution containing the drug is an aqueous solution.

Wood or bamboo used in the present invention, pine, cedar,
Hinoki, Toga, Killer, Oak, Oak, Oak, Beech, Zelkova, Birch, Sawara, Asunaro, Fir, Tsuga, Inumaki, Chestnut, Kunugi, Shii, Ho, Maple, Sakura, Shioji, Katsura, Enoki, Camellia, Rawan, Kokutan, Various hardwoods such as Ramin, cheetah, mahogany and eucalyptus, conifers, bamboo materials such as Moso bamboo and the like, stems, roots and petiole of woody annual or perennial plants are used. The amount of liquid absorbed and the rate of liquid absorption vary depending on the tree species used, the cutting time, and the site used. Therefore, when applied to a heated evaporator using this liquid system, the evaporation rate will differ. Therefore, the optimal material is selected in advance in advance. .

The liquid-absorbent core is usually cut out into a cylindrical shape, and it is desirable that the vertical direction of the column coincides with the fiber direction of wood or bamboo from the viewpoint of strength and ease of processing. If necessary, the shape is not limited to a circular column, but may be a polygonal column, and other types of work such as enlarging a heated portion are also possible. If necessary, a part of the absorbent core may be replaced with another material (for example, the upper portion is made of wood and the lower portion is joined with felt). The liquid absorbent core may be directly cut from wood or bamboo material, but if necessary, a laminated material of wood or bamboo material, that is, one or a combination of two or more kinds of strips may be used.

The liquid absorbent core of the present invention can be colored with carbon black or another pigment as needed. Further, antifungal, antiseptic, insect repellent, flame retardant, degreasing, and other treatments may be performed. Drying and heating can also be performed in the process of making the core.

The liquid absorbent core of the present invention is preferably used as a liquid absorbent core of a liquid heat evaporation apparatus for heating and scattering chemicals such as various insecticides, bactericides, deodorants, and fragrances for the purpose of insecticide, sterilization, aroma, and the like. be able to.

An example of an apparatus suitable for using the absorbent core of the present invention is shown in the drawings. In the figure, reference numeral 1 denotes a container containing a chemical solution 2, and the container 1 is detachably housed and held in a storage container 3.
An upper portion of the storage container 3 is open, and an annular (or a pair of semi-annular) heating elements 4 are fixed to the opening. 5 is a cord connected to the heating element 4. A liquid inlet 6 is provided at the upper part of the container 1, and a liquid absorbent core 7 is provided in the liquid inlet 6 so that the upper part thereof is disposed substantially in the center of the annular heating element 4. Is held in. The illustrated one is an example of an apparatus suitable for using the liquid absorbent core of the present invention. However, the present invention is not limited to this, and it goes without saying that apparatuses of various shapes can be used.

As the chemical liquid contained in the container 1, an insecticidal liquid, an aromatic liquid, or the like is used depending on the purpose. When the above-mentioned apparatus is used as a heat transpiration insecticidal apparatus, an insecticide solution is put in the container 1 and the heating element 4 is energized, and the surface temperature of the liquid absorbent core 7 is preferably 70 to 140 depending on the kind of the insecticide. Heat to ℃. If the heating temperature is too high, there is a problem in that thermal decomposition and polymerization of the drug are likely to occur and the amount of the volatile active ingredient is reduced, and the resulting high-boiling substances and the like accumulate in the liquid-absorbing core and the core due to the accumulation. This is not preferable since clogging of the film easily occurs. On the other hand, if the heating temperature is too low, volatilization is naturally delayed, and in some cases, only the solvent is volatilized, which may hinder the volatilization of the active ingredient.

Therefore, the optimum temperature is selected according to the type and concentration of the active ingredient, the volatility of the solvent, and the like.

As the insecticidal solution, a solution in which an insecticide is dissolved in various solvents is used. Solvents which have a high flash point, no odor and are toxicologically safe are preferred. Also, the boiling point of the solvent used depends on the heating temperature of the absorbent core, but 150 to 350 ° C.
Those which fall within the range are preferred. Those satisfying these conditions include saturated aliphatic or alicyclic hydrocarbons having 12 or more carbon atoms, and are commercially available as normal paraffins, isoparaffins or naphthenic hydrocarbons. In addition, as aromatic hydrocarbons,
Phenylxylylethane and the like can be used as odorless solvents. Of course, the solvent is not limited to these hydrocarbons as long as the solvent satisfies the above conditions. For example, various nonionic surfactants, preferably polyoxyalkylene alkyl ether-based solubilizers (refer to those capable of stabilizing insecticidal components in water in a clear state regardless of the presence or absence of micelles, and ordinary surfactants) In addition, water- and oil-compatible solvents are included.) To form an aqueous insecticide solution, which can eliminate the problem of flammability.

As the insecticide used in the present invention, various volatile insecticides conventionally used can be used, and examples thereof include pyrethroid-based insecticides, carbamate-based insecticides, and organic phosphorus-based insecticides. In general, pyrethroid insecticides are preferably used because of their high safety, and examples thereof include the following insecticides.

(A) 3-allyl-2-methylcyclopenta-2-en-4-one-1-yl dl-cis / trans-chrysanthemate (generic name aresulin: trade name pinamine: manufactured by Sumitomo Chemical Co., Ltd.) b) 3-allyl-2-methylcyclopenta-2-en-4-one-1-yl d-cis / trans-chrysanthemate (trade name: pinamine forte: manufactured by Sumitomo Chemical Co., Ltd .; hereinafter, insecticide) A) (c) d-3-allyl-2-methylcyclopenta-2-
En-4-one-1-yl d-trans-chrysanthemate (trade name: Exulin: manufactured by Sumitomo Chemical Co., Ltd.) (d) 3-allyl-2-methylcyclopenta-2-en-4-one-1 -Yl d-trans-chrysanthemate (generic name bioarrestrin) (e) 2-methyl-4-oxo-3- (2-propynyl) cyclopenta-2-enyl chrysanthemate (f) (s) -2- Methyl-4-oxo-3- (2-propynyl) cyclopenta-2-enyl d-cis / trans-chrysanthemate (general name: plerethrin, hereinafter abbreviated as insecticide B) (g) N- (3,4, 5,6-tetrahydrophthalimido) methyl dl-cis / trans-chrysanthemate (generic name: phthalsulin: trade name neopinamine: manufactured by Sumitomo Chemical Co., Ltd.) (h) 3-phenoxybenzyl -(4-ethoxyphenyl) -2-methylpropyl ether (generic name: ethofenprox) (i) 5-benzyl-3-furylmethyl d-cis / trans-chrysanthemate (generic name resmethrin: trade name chryslon) Forte: manufactured by Sumitomo Chemical Co., Ltd., hereinafter abbreviated as insecticide C) (j) 5-propargyl-2-furylmethylchrysanthemate (common name: flamemetryn) (k) 5-propargyl-2-furylmethyl d-cis /
Trans-chrysanthemate (trade name: Pinamin D forte: manufactured by Sumitomo Chemical Co., Ltd .; hereinafter abbreviated as insecticide D) (l) 3-phenoxybenzyl 2,2-dimethyl-3-
(2,2-dichlorovinyl) cyclo-R-propanecarboxylate (generic name: permethrin: trade name: Exmin: manufactured by Sumitomo Chemical Co., Ltd .; hereinafter abbreviated as insecticide E) (m) 3-phenoxybenzyl d-cis / trans-
Chrysanthemate (generic name phenothrin: trade name Smithrin: manufactured by Sumitomo Chemical Co., Ltd .; hereinafter abbreviated as insecticide F) (n) α-cyano-3-phenoxybenzyl α-isopropyl-4-chlorophenyl acetate (generic name fenvalerate) (Trade name: Sumicidin, manufactured by Sumitomo Chemical Co., Ltd.) (o) (S) -α-cyano-3-phenoxybenzyl
(S) -α-isopropyl-4-chlorophenyl acetate (generic name esfenvalerate) (p) (S) -α-cyano-3-phenoxybenzyl (1R.3R) -3- (2,2-dichlorovinyl)- 2,2-dimethylcyclopropanecarboxylate (q) (RS) -α-cyano-3-phenoxybenzyl (1RS) -cis / trans-3- (2,2-dichlorovinyl) -2,2-dimethylcyclopropane Carboxylates (generic name cypermethrin) (r) α-cyano-3-phenoxybenzyl d-cis /
Trans-chrysanthemate (generic name cyphenothrin) (s) α-cyano-3-phenoxybenzyl 2,2,3,3-
Tetramethylcyclopropanecarboxylate (generic name: fenpropatrin) (t) [(pentafluorophenyl) -methyl] (1R, 3
R) -3- (2,2-Dichlorovinyl) -2,2-dimethylcyclolopropanecarboxylate (generic name fenfluthrin) (u) 1-ethynyl-2-methyl-2-pentenyl d
-Cis / trans-chrysanthemate (generic name empentrin, hereinafter abbreviated as insecticide G) (v) 3-allyl-2-methyl-cyclopenta-2-en-4-one-1-yl 2,2,3 , 3-Tetramethylcyclopropanecarboxylate (general name teraresulin) (w) 1-ethynyl-2-methyl-2-pentenyl 2,
(X) 1-ethynyl-2-methyl-2-pentenyl 2,2,3,3-tetramethylcyclopropanecarboxylate
2-dimethyl-3- (2,2-dichlorovinyl) cyclopropanecarboxylate (y) N- (3,4,5,6-tetrahydrophthalimido) methyl d-cis / trans-chrysanthemate (brand name Neo Pinamine Forte: manufactured by Sumitomo Chemical Co., Ltd., hereinafter abbreviated as insecticide H) (z) Dimethyl (4-ethoxyphenyl) @ 3- (3-
Phenoxy-4-fluorophenyl) propyl disilane Among these, insecticides A to H are preferred in terms of their industrial availability, economy, efficacy, and safety, and above all, insecticide D is excellent in efficacy / economical efficiency. ing.

The concentration of the effective insecticidal component in the insecticidal solution is preferably 0.5% by weight or more and 20% by weight or less, and is preferably used in the concentration of 0.5 to 8% by weight.

These pesticides may be used alone or in combination.

Also, if necessary, stabilizers, deodorants, synergists, pigments,
In addition, a small amount of an auxiliary agent can be added to the chemical solution.

Similarly, when used for the purpose of aroma, various natural and artificial flavors can be used, for example, animal and vegetable natural flavors, hydrocarbons, alcohols, phenols, aldehydes, ketones, lactones, These are artificial flavors such as oxides and esters, and one of these can be used alone, or two or more can be used in combination. Furthermore, various chemicals such as a deodorant and a bactericide repellent can be used depending on the purpose as long as the chemicals are volatilized by heating. The concentration of such various drugs is preferably 0.5 to 10% by weight.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to specific examples, but the present invention is not limited thereto.

In the following Examples and Comparative Examples, oil absorption means
It is the weight (g) of normal paraffin absorbed by 1 cc, and the oil absorption rate is as follows. The liquid absorption core is cut into 70 mm, the lower 15 mm is immersed in the normal paraffin at room temperature, and the normal paraffin reaches the top of the core. Say time.

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

The water absorption and the water absorption rate are measured in the same manner for an aqueous solution containing 40% by weight of a solubilizer (diethyleneoxybutyl ether).

Examples 1 to 4 Hinoki wood, Ramin wood and Moso bamboo were processed into a liquid absorbing core having a diameter of 7 mm and a length of 70 mm. The oil absorption amount, oil absorption speed or water absorption amount, and water absorption speed were as shown in Table 1.

Comparative Example 1 Diatomaceous earth 100 parts, wood flour (K-100 manufactured by Casino Co., Ltd.) 48
Part, activated carbon (Takeda Pharmaceutical Co., Ltd., Shirasagi C) 12 parts α-
274 parts of water was added to 40 parts of starch, kneaded, extruded, and air-dried to obtain a liquid absorbent core having the same dimensions as above. The oil absorption was 0.33 g / cc, and the oil absorption rate was 8 hours.

Comparative Example 2 Diatomaceous earth 40 parts Clay 100 parts Gypsum 160 parts, CM
An absorbent core having the same dimensions as above was prepared from 8 parts of C-Na and 0.92 parts of Sumilizer BP-76 (manufactured by Sumitomo Chemical Co., Ltd., antioxidant). The oil absorption rate was 9 hours, and the oil absorption was 0.32 g / cc.

Volatilization test example 1 A liquid absorption core obtained in Examples 1 and 3 was placed in a heating evaporator shown in the drawing,
A commercially available liquid absorbent core (a chemical solution washed and dried with hexane manufactured by Earth Pharmaceutical Co., Ltd.) and the liquid absorbent cores obtained in Comparative Examples 1 and 2 were set, and the insecticide D1.8% and BHT1% were normal. 35 g of a drug solution dissolved in paraffin is put in the
C. to conduct a volatilization test. When the chemical solution became insufficient by the predetermined heating time, only the chemical solution was replenished at that time. In the volatilization test, (1) the amount of the chemical solution decreased per hour and (2) the amount of the insecticide volatilized per hour were examined. In (2), the insecticide was trapped with a silica gel packed column at regular intervals, the insecticide was extracted with acetone, and analyzed by gas chromatography.

[Effects of the Invention] As described above in detail, the liquid-absorbent core of the present invention is very simple to produce, and is superior in structure and performance to the conventional one.

Therefore, the chemical vaporization method of the present invention using the liquid absorbent core also has an effect exceeding that of the conventional method. For example, even when the drug is an aqueous solution, it can be carried out without physical deterioration of the liquid absorbent core. .

[Brief description of the drawings]

The drawing is a longitudinal section showing one embodiment of an apparatus suitable for carrying out the method of the present invention. In the figure, 1 ... container, 2 ... chemical solution 3 ... container container, 4 ... heating element 5 ... cord, 6 ... chemical liquid inlet 7 ... liquid absorption core

Claims (4)

(57) [Claims] 1. An absorbent core made of wood or bamboo. 2. A vaporization method in which a solution containing a drug is absorbed into an absorbent core, and the absorbent core is heated to evaporate the drug, wherein the absorbent core is the absorbent core according to claim 1. A method for evaporating a drug, comprising: 3. The method according to claim 2, wherein said solution is an aqueous solution. 4. The method according to claim 2, wherein the drug is pyrethroid.