JP2791918B2 - Absorption wick for heat evaporation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a liquid absorbent core for heat evaporation, and more particularly, to a liquid absorbent core in a chemical solution for the purpose of insecticide, sterilization, deodorization, aroma, etc. While immersing a part to absorb the drug solution into the core,
The present invention relates to a liquid-absorbing core used in a wicking-type heating and evaporating apparatus that evaporates a liquid medicine absorbed by heating an upper portion of the core.

[Conventional technology]

For example, a method in which a part of a porous absorbent core is immersed in an insecticide to absorb the insecticide in the immersion, and the upper part of the core is heated to evaporate the absorbed insecticide. Transpiration insecticidal methods have been known for a long time. For example, Japanese Utility Model Publication No. 43-25081 describes a system using direct heating, but in the case of using direct heating, the method of indirect heating tends to be generally adopted because the decomposition of the drug is severe. As a method by indirect heating, a method of heating with a felt etc. between the absorbent core and the heating element is used
No. 36-12459, described in Japanese Utility Model Publication No. 46-22585,
Further, a method of heating the liquid absorbing core and the heating element at a constant interval is disclosed in Japanese Utility Model Publication No. 43-26274, Japanese Utility Model Publication No. 44-8361,
JP-B-45-14913, JP-B-45-19801, JP-B-45-29244, JP-B-61-23163, and JP-A-60
-161902 and the like.

In addition, JP-B-61-23163 discloses the use of arrestin or an isomer thereof as an insecticide, an insecticide obtained by dissolving the same in a hydrocarbon solvent having a specific boiling point range, and a porous absorbent core, Porous porcelain, glass fiber, inorganic fiber selected from asbestos hardened with gypsum and / or bentonite, and inorganic selected from kaolin, talc, diatomaceous earth, perlite, bentonite, alumina, silica, silica alumina and titanium It has been proposed to use a liquid-absorbent core made of a powder solidified with starch.

Further, Japanese Patent Application Laid-Open No. 60-161902 proposes an insecticidal liquid composition for a liquid absorbent core in which a specific antioxidant is added to an insecticide solution.

[Problems to be solved by the invention]

In the case of the heat evaporation method by the above-mentioned liquid absorption core heating method,
Since the porous liquid absorbent core is generally made of felt, nonwoven fabric, asbestos, etc., the liquid absorption rate is relatively high, and as the liquid absorbent core is heated, only the solvent in the drug solution evaporates and the drug is sufficiently absorbed. Stable for a long period of time because it is difficult to evaporate, and it is easy to cause clogging of the absorbent core due to high boiling substances generated by thermal decomposition of the drug or high boiling substances contained in the solvent, etc. It was difficult to sustain volatilization.

On the other hand, JP-B-61-23163 proposes a method for improving the problem that it is difficult to stably volatilize pesticides by evaporating only the solvent in the pesticidal solution, and its working example. Describes that a ceramic porous core is used as a liquid absorbing core. However, ceramics generally need to be fired at an extremely high temperature and for a long time in order to secure sufficient strength. In addition, the raw materials are expensive and the production cost is increased. Even though the strength and strength are good, none of them has been satisfactory in terms of economics such as manufacturing cost and productivity.

Therefore, in the heat evaporation method by the liquid absorbent core heating method, a liquid absorbent core molded from inorganic powder is generally used, and as a method for producing such a liquid absorbent core, inorganic powder and A method of kneading a binder such as starch, a semi-synthetic cellulose derivative, and carboxymethyl cellulose (CMC) with water or hot water and extruding the mixture is generally used (see Japanese Patent Publication No. 23163/1986).

However, when the inorganic powder is simply solidified with a small amount of starch, the strength of the liquid absorbent core is extremely weak, and the moldability is poor, so that it is extremely difficult to produce the liquid absorbent core. In this case, a large amount of starch is required, and various problems occur.

That is, starch is generally a stored starch stored by plants, and usually pure starch is a mixture of about 80% amylose and about 20% amylopectin, insoluble in cold water, and heated to 50-70 ° C. It becomes a viscous glue. However, the viscosity varies greatly depending on the temperature, and this change in viscosity becomes a problem during production.In addition, depending on the cooling method and concentration, starch aging, that is, amylose is oriented to form micelles, and troubles such as generation of mold and production There is a problem in that it is difficult to ensure the stability of the product, for example, because the strength may be insufficient or the strength may be deteriorated later. In addition, in order to improve the strength of the absorbent core, it is necessary to use a large amount of starch, but as the amount is increased, the absorbent core loses porosity, making it difficult to suck up the chemical solution, resulting in insufficient evaporation. Has disadvantages. On the other hand, in the case of CMC, the purpose can be achieved by using a small amount as compared to starch, but when both CMC and starch are heated in a state of sucking up a chemical solution for a long time, decomposition and the like proceed, and strength is deteriorated. Further, there is a problem that deterioration of a binder such as starch and CMC affects evaporation of the drug, decomposition of the drug, polymerization, and the like, and stable evaporation cannot be obtained over a long period of time.

In addition, the state of solidification of water-soluble polymers such as starch and CMC changes depending on environmental humidity. That is, at high humidity,
When these water-soluble polymers contain water, they are softened and the strength of the liquid-absorbing core is significantly impaired.

Further, when the absorbent core is immersed in the chemical solution for a long period of time or heated in a state where the chemical solution is sucked up, the chemical solution in which the water-soluble polymer is impregnated in the absorbent core or the chemical solution existing around the core is further removed. Dissolves or swells in water, gradually closing the pores (pores) of the porous liquid absorbent core, making it difficult to suck up the chemical solution in a relatively short period of time, and obtaining stable evaporation over a long period of time. It becomes difficult.

In addition, starch, a liquid absorbent core molded using a binder such as CMC, in the drying step after molding, the liquid absorbent core is likely to crack or bend, and further requires a long drying time, it was completed The dimensional stability of the liquid absorbent core was also poor, and it was difficult to produce a liquid absorbent core of stable quality with high production efficiency.

Furthermore, liquid-absorbent cores using a water-soluble polymer such as starch or CMC as a binder cannot be used for aqueous chemicals because the water resistance of these binders is insufficient. A method for solving this disadvantage is disclosed in Japanese Unexamined Patent Publication No. Hei.
231031, JP, JP-A-2-234628, has been proposed, but the liquid absorbent wick described in JP-A-2-231031, the use of natural wood by cutting processing, quality stabilization is extremely high Have difficulty. On the other hand, the liquid absorbent core described in JP-A-2-234628 requires a complicated work in terms of molding processing in order to form a double structure of the central holding material and the surrounding porous liquid absorbent evaporation layer. There is a disadvantage.

Accordingly, an object of the present invention is to solve the above-mentioned problems, hardly cause clogging of the liquid absorption core when using heating, and to effectively evaporate a sufficient drug for a long period of time. To provide a core.

Furthermore, an object of the present invention is to solve the problems caused by the binder as described above, and to excel in core strength, dimensional stability and moldability, and to use the oil solution of a chemical solution regardless of whether it is water-based, for heat evaporation. It is to provide a liquid absorbent core.

It is a further object of the present invention to provide an absorbent core for heat evaporation that can be manufactured with low manufacturing cost and with constant quality with high productivity.

[Means for solving the problem]

The liquid absorbent core for heat evaporation of the present invention absorbs the liquid chemical by dipping a part of the liquid absorbent core into the liquid chemical and heats the upper part of the liquid core to evaporate the liquid medicine absorbed by heating the upper part of the liquid core. A liquid absorbent wick used in a heat evaporation method, which is formed and fired from a mixture of an inorganic powder and / or an organic powder and a binder that can be carbonized by high-temperature firing together with other additives as necessary. It is characterized by having.

It is particularly preferable to use tar or pitch or a mixture thereof as the binder, and it is particularly preferable to perform calcination at a calcination temperature of 450 to 1300 ° C. on the core surface.

[Function and Mode of the Invention]

The absorbent core for heat evaporation of the present invention is produced by molding a mixture obtained by mixing a binder capable of being carbonized by inorganic powder and / or organic powder at a high temperature, and other additives as necessary, followed by firing. Therefore, in addition to being able to be manufactured with relatively high productivity, the binder is carbonized and stabilized by firing, and the powders are firmly bonded to each other.
Excellent core strength and dimensional stability.

In addition, when actually using the heat-absorbing liquid absorbent core, one end of the liquid absorbent core is immersed in a chemical solution.For example, when an insecticide is used as an active ingredient, the core surface temperature is set to 100 to 130 ° C. It is common to heat so that At this time, when using a liquid absorbing core obtained by simply extruding and drying a mixture containing a water-soluble polymer such as starch as a binder, the dissolution or swelling of the binder by the chemical solution as described above. Although the clogging and deterioration of the liquid absorbent core caused by the water-soluble polymer itself and the deterioration of the water-soluble polymer itself when heated to 100 to 130 ° C. could not be completely avoided, it was impossible to completely avoid the adverse effect on the drug evaporation. The liquid absorbent core produced by firing as in the invention is free from such a problem. That is, since the binder is carbonized by firing and is stable, it hardly dissolves or swells due to the chemical solution, and since it is used at a temperature much lower than the firing temperature, deterioration of the carbonized binder itself hardly occurs. do not do.
Therefore, there is no clogging of the absorbent core due to dissolution or swelling of the binder, and there is no adverse effect on the evaporation of the drug due to deterioration of the binder itself, and it is possible to effectively and stably evaporate a sufficient amount of the drug over a long period of time. it can.

Furthermore, since the liquid absorbent core for heat evaporation according to the present invention has good dimensional stability as described above, liquid leakage during use can be reduced. In other words, liquid leakage during use can be classified into liquid leakage caused by the flow of liquid inside the liquid absorbent core and liquid leakage caused by the gap between the liquid absorbent core and the container. This makes it possible to make a tight fit with a reduced gap between the liquid and the liquid, thereby reducing liquid leakage.

Examples of the carbonizable binder used in the present invention include tar, pitch, methylcellulose / hydroxypropylmethylcellulose copolymer (MC / HPMC), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polymethyl methacrylate (PMMA), and acrylic type. Resin, polystyrene (PS), polypropylene (PP), polyethylene (PE), ethylene vinyl acetate copolymer (EVA), phenolic resin, polyethylene glycol (PEG), cellulose derivatives, CMC, starches, urethane, wax,
Examples thereof include wax emulsions, and among them, tar, pitch or a mixture thereof is particularly preferable.

That is, when tar, pitch or a mixture thereof is used, the residual carbon content derived from these binders after firing is excellent in the function of acting as a binder, so that good strength is easily achieved as compared with the case where another binder is used. There is an advantage that can be obtained. In addition, these binders are generally inexpensive compared to other resins, and the mixing and extrusion using these resins have extremely low stickiness of molded products, and are easy to handle and have stable dimensions. High-speed molding is possible, and the production efficiency is much better than a general ceramic liquid absorbent core or a liquid absorbent core fixed using a water-soluble polymer. Therefore, it is possible to significantly reduce the manufacturing cost of the liquid absorbent core.

Tar and pitch are classified according to the type of principle.
Examples of the raw material include coal, wood, petroleum, and the like. But,
The tar and pitch used for the liquid absorbent core are easy to handle during molding, that grades with various properties have been commercialized, that they are easily available and that the quality is stable, that they are inexpensive. For some reasons, coal-based materials are most preferred, but are not limited.

Various materials can be used as the inorganic powder and / or the organic powder as the base material of the absorbent core, for example, clay, talc, kaolin, diatomaceous earth, gypsum, perlite, bentonite, acid clay, volcanic rock, glass fiber, Examples include rock wool, sepiolite, clay, coke, graphite, wood flour, cellulose, pulp, linter, polymer resin, and the like, but are not limited thereto. Among them, diatomaceous earth, sepiolite, wood flour, cellulose, pulp, and linter are useful for securing the porosity and liquid absorption required for the liquid absorption core.

The liquid-absorbent core of the present invention is obtained by adding and mixing at least one kind of the above-mentioned binder and additives described below as necessary to one or more kinds of the base powder, molding the mixture by an appropriate method, and then firing. Can be manufactured. The blending ratio of the binder to the base powder can be appropriately selected according to the desired porosity of the obtained liquid absorbent core, the liquid absorbing speed, and the like.
In order to impart sufficient strength to the liquid absorbent core, the mixing ratio (weight ratio) of the base powder and the binder is generally limited to the range of 100: 1 to 80, preferably 100: 7 to 60.

On the other hand, the firing temperature can be arbitrarily set within a range in which a liquid absorbent core can be manufactured, but in order to secure necessary properties as the liquid absorbent core, it is preferable to maintain 450 to 1300 ° C. on the surface of the core. That is, if the firing temperature is less than 450 ° C., sufficient strength is not obtained, while if it is higher than 1300 ° C., carbonization of the binder or the base material is significantly promoted,
It exhibits an adsorption ability like activated carbon, which is not preferable because it hinders evaporation of the chemical solution.

The baking time is also arbitrary, but the baking time is 10 to 24 in consideration of securing necessary strength as a liquid-absorbing core or transpiration of chemicals, and keeping good production efficiency.
The time is preferably set to 0 hours, preferably 40 to 150 hours, but is not particularly limited.

In addition, as long as the properties of the porous liquid absorbent core are not impaired, pigments, dyes, preservatives, other fixing agents, antioxidants, water / oil resistance improvers, flame retardants, sulfur / Other additives such as a strength improver such as zinc chloride may be blended.

Examples of the antioxidant that can be added include the following. That is, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate,
2'-methylene-bis (4-methyl-6-t-butylphenol), 2,2'-methylene-bis (4-ethyl-6
-T-butylphenol), 4,4'-methylene-bis (4-methyl-6-t-butylphenol), 4,4'-
Methylene-bis (2,6-di-t-butylphenol),
4,4'-butylidene-bis (3-methyl-6-t-butylphenol), 4,4'-thiobis (3-methyl-6-
t-butylphenol), 1,3,5-trimethyl-2,4,6-
Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 1,1,3-tris- (2-methyl-5-t
-Butyl-4-hydroxyphenyl) butane, tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)] methane, BHT, BEA, 3,5-di-
t-butyl-4-hydroxyanisole, mercaptobenzimidazole, dilauryl-thio-di-propionate, 2-t-butyl-4-methoxyphenol, 3-
t-butyl-4-methoxyphenol, 2,6-di-t-
Butyl-4-ethylphenol, α-tocopherol,
Ascorbic acid, erythorbic acid, 1,1-bis (4-hydroxyphenyl) cyclohexane, octadecyl-3,
5-di-t-butyl-4-hydroxyhydrocinnamate, phenyl-β-naphthylamine, N, N-diphenyl-p-phenylenediamine, 2,2,4-trimeryl-1,2-
Dihydroquinoline polymer, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, 2,2-thiobis (4
-Methyl-6-t-butylphenol), 3,5-di-t
-Butyl-4-hydroxy-benzylphosphonate-diethyl ester, bis (3,5-di-t-butyl-4
-Ethyl hydroxybenzylphosphonate) calcium:
Polyethylene wax, octylated diphenylamine,
Tris [2- (3 ', 5'-di-tert-butyl-4'-hydroxyhydro-cinnamoyloxyl) ethyl] isocyanurate, tris- (4-tert-butyl-2,6-dimethyl-3-hydroxy Benzyl) isocyanurate, 3,9
-Bis [1,1-di-methyl-2- {β- (3-t-butyl-4-hydroxy-5-methyl-phenyl) propionyloxy} ethyl] -2,4,8,10-tetraoxa Spiro [5,5] undecane, ditridecyl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate,
Triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-
t-butyl-4-hydroxyphenyl) propionate], N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 2,2-thio-diethylenebis [ 3- (3,5-di-t-butyl-4
-Hydroxyphenyl) propionate], N, N'-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine, tris- (3,5-di-t-butyl-4) -Hydroxybenzyl) -isocyanurate and 2,4-bis- (n-octylthio) -6
(4-hydroxy-3,5-di-t-butylanilino)-
Examples include compounds such as 1,3,5-triazine.

These compounds can be used alone or in combination of two or more. As the method of addition, addition to the obtained absorbent core or addition to the chemical solution is conceivable, but is optional. When used in an absorbent core, it is used in an amount of 0.01 to 3% by weight, preferably 0.03 to 1% by weight, based on the total amount of the core. When added to a drug solution, 0.0015 to 0.4% by weight of the total drug solution, preferably
0.004 to 0.2% by weight.

By the addition of these antioxidants, effects such as prevention of thermal deterioration during use under heating, decomposition of the chemicals, prevention of polymerization, and improvement of long-term stability over time can be obtained.

In addition, as an antioxidant generally called a peroxide decomposer, dilauryl thiodipropionate (DLTP) or distearyl thiodipropionate (DSTP) may be used in combination with the antioxidant. .

Furthermore, by using an ultraviolet absorber as a stabilizer, light resistance during storage and use can be further improved.

The molded absorbent core of the present invention is microporous and has a considerably smaller amount of liquid absorption than a liquid absorbent core mainly composed of a fibrous material, and is therefore used for a long period of time. It is suitable as. In particular, by setting the porosity in such a porous liquid absorbent core to 20 to 50%, preferably 25 to 45%, it is possible to achieve both reduction of liquid leakage and stable evaporation of the chemical solution for a long period of time.

That is, as described above, the liquid leakage can be classified into a liquid leakage caused by the flow of the liquid inside the liquid absorption core and a liquid leakage caused by the clearance between the liquid absorption core and the container.
% Or less, it is possible to suppress the flow of excess liquid inside the liquid absorbent core, and to reduce liquid leakage. Further, in order to ensure stable vaporization of the chemical solution over a long period of time as a liquid-absorbing wick used in a heating and vaporizing apparatus, a porosity of 20% or more, preferably 25% or more is required.

The porosity is measured and calculated as follows.

After placing the absorbent core in a desiccator and applying a substantially vacuum, an aliphatic saturated hydrocarbon is placed in the desiccator, and the absorbent core is immersed in the desiccator and brought to atmospheric pressure. At this time, the weight increase of the absorbent core Is measured, and the porosity is calculated by the following equation.

The liquid absorbent core of the present invention is a liquid absorbent core of a wicking-type heat evaporation device that heats and evaporates various insecticides, bactericides, deodorants, and fragrances for the purpose of insecticide, sterilization, deodorization, aroma, and the like. Can be suitably used. 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 held at the liquid inlet 6 so that the upper part is disposed at the center of the annular heating element 4. . 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.

The chemical contained in the container 1 may be any suitable solvent such as an insecticide, an insect repellent, a repellent, a fungicide, a bactericide, a deodorant, an aromatic, etc., as an active ingredient, depending on the purpose. And the like are used. When the above 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 100 to 130 ° C. depending on the kind of the insecticide. Heat so that 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 evaporative active ingredient is reduced. In addition, the resulting high-boiling substances and the like are accumulated in the liquid-absorbing core and the core is thereby formed. This is not preferable because clogging of the film easily occurs.

As the insecticide, a solution in which various insecticides are dissolved in an aliphatic hydrocarbon-based solvent can be used.However, unsaturated aliphatic hydrocarbons alone are not preferable because they have an unpleasant odor, and aliphatic saturated hydrocarbons are preferably used. Optimal. However, the unsaturated unsaturated hydrocarbon may be contained in a quantitative ratio that does not cause the above-mentioned disadvantages. Also, among the aliphatic saturated hydrocarbons,
If the number of carbon atoms is 19 or more, it has a high viscosity or is in a gel state or a solidified state, so that liquid absorption of the insecticidal solution into the absorbent core cannot occur smoothly. It is. On the other hand, as the number of carbon atoms is smaller, the total effective transpiration rate of the insecticidal component tends to decrease. Therefore, in order to obtain a sufficient transpiration rate, the carbon number needs to be 12 or more. However, as long as it is a quantitative ratio that does not cause the above-mentioned inconvenience, there is no problem in blending an aliphatic hydrocarbon outside the above range.

Examples of the aliphatic saturated hydrocarbon that can be used in the present invention include dodecane (C ₁₂ ), tridecane (C ₁₃ ), tetradecane (C ₁₄ ), pentadecane (C ₁₅ ), hexadecane (C ₁₆ ), heptadecane (C ₁₇ ), Octadecane _C18 and mixtures thereof, and commercially available solvents containing these as main components, such as No. 0 Solvent H (manufactured by Nippon Oil Co., Ltd.), No. 0 Solvent M (manufactured by Nippon Oil Co., Ltd.), and normal paraffin ( Mitsuishi / Texaco Chemical Co., Ltd.), IP Solvent 2028 (Idemitsu Petrochemical Co., Ltd.) and the like can also be used.

As the insecticide used in the present invention, various transpirant 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.

-3-allyl-2-methylcyclopent-2-ene-4
-On-1-yl dl-cis / trans-chrysanthemate (generic name: Aresulin: trade name Pinamine: manufactured by Sumitomo Chemical Co., Ltd.) 3-Allyl-2-methylcyclopenta-2-ene-4
-On-1-yl-d-cis / trans-chrysanthemate (generic name: dl, d-T80-aresulin: trade name pinamine forte: manufactured by Sumitomo Chemical Co., Ltd.) d-3-allyl-2-methyl Cyclopenta-2-en-4-one-1-yl d-trans-chrysanthemate (generic name d, d-T80-aresulin: trade name exulin: manufactured by Sumitomo Chemical Co., Ltd.) 3-allyl-2- Methylcyclopenta-2-ene-4
-On-1-yl d-trans-chrysanthemate (trade name: bioarrestrin) 2-Methyl-4-oxo-3- (2-propynyl) cyclopenta-2-enyl-chrysanthemate (generic name d,
d-T80-Praletrin: trade name ETOK: manufactured by Sumitomo Chemical Co., Ltd.) N- (3,4,5,6-tetrahydrophthalimide) -methyl
dl-cis / trans-chrysanthemate (generic name: phthalsulin: trade name neopinamine: manufactured by Sumitomo Chemical Co., Ltd.) 5-benzyl-3-furylmethyl d-cis / trans-chrysanthemate (generic name: d-T80-resmethrin : Trade name Chrisron Forte: manufactured by Sumitomo Chemical Co., Ltd.)-5- (2-propynyl) -3-furylmethyl d-cis / trans-chrysanthemate (generic name: d-T80-framethrin: trade name pinamine-D) Forte) ・ 3-phenoxybenzyl-2,2-dimethyl-3-
(2 ', 2'-dichloro) vinylcyclopropane carboxylate (generic name permethrin: trade name Exmin:
Sumitomo Chemical Co., Ltd.) 3-phenoxybenzyl d-cis / trans-chrysanthemate (generic name phenothrin: trade name Smithrin: Sumitomo Chemical Co., Ltd.) α-cyanophenoxybenzyl isopropyl-4-
Chlorophenyl acetate (generic name fenvalerate:
Trade name Sumisaidin: manufactured by Sumitomo Chemical Co., Ltd.) (S) -α-cyano-3-phenoxybenzyl (1R,
(Cis) -3- (2,2-Dichlorovinyl) -2,2-dimethylcyclopropanecarboxylate (R, S) -α-cyano-phenoxybenzyl (1R, 1S)
-Cis / trans-3- (2,2-dichlorovinyl) -2,2
-Dimethylcyclopropanecarboxylate (generic name cypermethrin) α-cyano-3-phenoxybenzyl d-cis / trans-chrysanthemate (generic name cyphenothrin: trade name gochelate) 1-ethynyl-2-methyl-2 -Pentenyl cis /
Trans-Chrysanthemato (generic name empentrin:
(Trade name: Vaporthrin) ・ 3-allyl-2-methyl-cyclopenta-2-ene-
4-one-1-yl-2,2,3,3-tetramethylcyclopropanecarboxylate (general name teraresulin) 2- (para-ethoxyphenyl) -2-methylpropyl-3-phenoxybenzyl ether (generic name) Etofenprox) 1-ethynyl-2-methyl-2-pentenyl-2,2,3,
3-tetramethylcyclopropanecarboxylate 1-ethynyl-2-methyl-2-pentenyl-2,2-
Dimethyl-3- (2,2-dichlorovinyl) cyclopropane-1-carboxylate 2,3,4,5,6-pentafluorobenzyl-3- (2,2-dichlorovinyl) -2,2-dimethylcyclo Propane carboxylate The concentration of the effective insecticidal component in the insecticidal solution is 0.5% by weight.
The content is preferably not less than 5% by weight and not more than 5% by weight, and preferably, it is used at a concentration of 0.5 to 3% by weight. In the case of mosquito killing, for example, pinamine forte is 1.5 mg / hr or more, and bioarethrin is 1.
Sufficient mosquito-killing effects can be achieved with transpiration of 2 mg / hr or more, extrins of 0.6 mg / hr or more, and ethoks of 0.3 mg / hr or more.
Therefore, it is preferable to use ethok as an insecticide, since a sufficient insecticidal effect can be exhibited using a low-concentration insecticidal solution.

Similarly, when used for the purpose of aroma, various kinds of natural and artificial flavors can be used. For example, animal and vegetable natural flavors, hydrocarbons, alcohols, phenols, aldehydes, ketones, lactones, oxides And artificial flavors such as esters and the like. One of these can be used alone, and two or more can be used in combination. For example, limonene or the like is added to an aliphatic hydrocarbon in an amount of 0.5 to 1.0 wt.
/ wt%, 100% using the porous absorbent core of the present invention.
It has been confirmed that when heated to ~ 130 ° C, an appropriate amount of fragrance is stably emitted during a predetermined period from the initial stage of heating until the fragrance liquid disappears.

Furthermore, various chemicals such as a deodorant, a bactericide, and a repellent can be used depending on the purpose, as long as the chemicals evaporate by heating. As such various drug concentrations, 0.5 to 10
% By weight is preferred.

In addition, a masking agent such as a fragrance may be blended in the above-mentioned chemical solution.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to examples.

Examples 1 to 12 The components having the formulations shown in Table 1 below were mixed, extruded, and then baked so that the surface temperature of the core was 800 ° C. Samples No. 1-800, 2-800, respectively. 11 to 800 and 12 to 800 (the numbers 1 to 12 indicate the firing temperature in Example No. 800; the same applies hereinafter). In the following, unless otherwise specified, the firing temperature is at the core surface.

In Examples 1, 3 and 6, the sintering temperature was 300 ° C.
Samples of 50 ° C, 1000 ° C, 1300 ° C, and 1500 ° C were also prepared.
o.1-300 ... 1-1500,3-300 ... 3-1500,6-300 ...
15 samples of 6-1500 were also prepared.

For each sample, the size of the liquid absorbent core was about 7 mm in diameter and 70 mm in length.

Comparative Examples 1 to 6 The components of the formulation shown in Table 2 below were mixed with water or hot water, extruded, dried, and dried to about 7 mm in diameter and 70 mm in length.
The size of the liquid absorbent wick was manufactured.

Test Example 1 [Strength at High Humidity] The strength of the absorbent core left in an environment of 25 ° C., 75% RH and 25 ° C., 90% RH for 24 hours or more was measured by the following method.

Each 1cm is supported by a flat plate from both ends of the absorbent core, and a round bar of 1cm in diameter and 3cm in length is arranged so that the center of the core is perpendicular to the core,
Pressure was applied from above the round bar, and the strength immediately before the core was broken was measured. Table 3 shows the results.

As is clear from the results shown in Table 3 above, the core manufactured by firing as in the example of the present invention was obtained at 25 ° C. and 75% R.C.
While the strength at 25 ° C and 90% RH is almost the same as that of H., cores formed using water-soluble polymers such as CMC and starch as in Comparative Examples 2 and 3 have high humidity. It can be seen that this causes significant strength deterioration.

Also, as in the sample Nos. 1-300 and 6-300 of the embodiment,
If the firing temperature is 300 ° C, the strength is 25 ° C, 75% RH, 25%
It can be seen that the temperature is low both in ° C and 90% RH. On the other hand, it can be seen that the core manufactured by firing at a temperature of 450 ° C. or more can secure good strength without being affected by the environmental humidity.

Test Example 2 [Dimensional stability] Sample Nos. 2-800, 5-800, 8-450, 8-800, 8 of Examples
Take out 100 samples each of -1200 and Comparative Examples 1 and 4,
The dimensional stability was measured by measuring their diameter and determining the standard deviation. Table 4 shows the results.

As described above, the core manufactured by sintering as in the example has a much more stable core diameter than the core formed using the water-soluble polymer as in the comparative example. Thereby, the core manufactured by firing can reduce liquid leakage.

Test Example 3 [Evaporation test-oily chemical solution] A porous liquid absorbent core was set in a heating evaporator shown in the drawing.
The content liquid in the container was 50 ml of a mixed aliphatic saturated hydrocarbon solution having 14 to 17 carbon atoms containing the insecticide shown in Table-5.

The heating element was energized to heat the upper surface of the absorbent core to 120 ° C., and the amount of insecticide evaporated per heating time was measured. The results are shown in Table-6.

Evaporation amount: Evaporation vapor was trapped at regular intervals by a silica gel packed column for a unit time, extracted with chloroform, concentrated, and quantitatively analyzed by gas chromatography.

As is clear from Table-6, in the transpiration of the drug,
The sintering temperature has a great influence, and the wick manufactured at a sintering temperature of 1300 ° C. or less shows stable evaporation of the drug without adding an antioxidant or the like for a long time of 400 hours. On the other hand, if the sintering temperature is 1500 ° C., the amount of drug evaporated per unit time is significantly reduced, which is not preferable.

In the case of the core formed using the water-soluble polymer as in the comparative example, a marked decrease in the evaporation of the drug is observed as the use time is extended.

Test Example 4 [Evaporation Test—Aqueous Chemical Solution] An aqueous solution containing the antibacterial and antifungal agents shown in Table-7 was prepared.

Chemical Nos. ,,, are used to improve dispersibility.
An aqueous solution was obtained after premixing with polyoxyethylene nonylphenyl ether, which was twice as much as each drug.

As the chemical 2 of the heating evaporator shown in the drawing, a chemical,
, And the respective liquid absorbent cores of Sample Nos. 2-800, 6-800, 8-800 of the examples and Comparative Examples 2 and 6 were set.

When the liquid absorbent core was observed 72 hours after the liquid absorbent core was set, the liquid absorbent cores of Comparative Examples 2 and 6 collapsed in the container, and the antibacterial and fungicidal effects could not be confirmed.

On the other hand, since no abnormality was observed in each of the liquid absorbent cores of Sample Nos. 2-800, 6-800, and 8-800 of the example, the following test was further performed.

Test Example 5 [Test for confirming the antibacterial and antifungal effects] An agar medium coated with a spore suspension obtained by culturing falling live bacteria was placed in a 50 glass water tank. The heating evaporator was placed in the glass water tank at a distance of 30 cm from the agar medium, and the heating element was energized to heat the upper side surface of the absorbent core to 105 ° C. The glass aquarium was covered, sealed, and cultured under a constant condition of 25 ° C.

Controls without a heat evaporator were also cultured under the same conditions. The results are shown in Table-8.

As is clear from the results shown in Table 8 above, the core produced by calcination of the present invention exhibits a stable effect even when an aqueous chemical is used, while the water-soluble core such as the comparative example shows. A core formed using a polymer cannot be used at all with an aqueous drug solution.

〔The invention's effect〕

As described above, the absorbent core for heat evaporation according to the present invention is formed by molding and firing a mixture of an inorganic powder and / or an organic powder and a binder that can be carbonized by high-temperature firing. The following effects and advantages can be obtained.

B) The base powder is firmly bound by the binder by firing, and is excellent in core strength and dimensional stability.

B) Since the binder is not dissolved or swelled by the chemical solution, and is not affected by the heating temperature during heating, there is no clogging or deterioration of the absorbent core due to these, and the drug is used for a long period of time. Can be effectively and stably evaporated.

C) The chemical can be used irrespective of whether it is oily or aqueous, and in any case, stable transpiration can be obtained when used under heating.

D) Good core strength can be maintained over a long period of time without being affected by the humidity of the surrounding environment.

E) In particular, by using tar, pitch, or a mixture thereof as a binder, good moldability can be obtained, and a liquid absorbent core of stable quality can be produced with high productivity and low production cost.

F) Since it has excellent dimensional stability, it can be tightly fitted to the container, and liquid leakage is prevented.

Other effects and advantages of the present invention will be easily understood by those skilled in the art from the description of this specification.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing one embodiment of an apparatus suitable for carrying out the method of the present invention. 1 is a container, 2 is an insecticide, 4 is a heating element, and 7 is a liquid absorbing core.

Claims (3)

(57) [Claims] 1. A heating and evaporation method in which a part of an absorbent core is immersed in a chemical solution to absorb the chemical solution into the core, and the upper part of the core is heated to evaporate the absorbed chemical solution. A liquid absorbing core formed by shaping and firing from a mixture of an inorganic powder and / or an organic powder and a binder which can be carbonized by high-temperature firing together with other additives as necessary. Liquid absorption core for heat evaporation. 2. The absorbent core for heat evaporation according to claim 1, wherein the binder is tar, pitch or a mixture thereof. 3. The absorbent core for heat evaporation according to claim 1, wherein the absorbent core is formed by firing at a firing temperature of 450 to 1300 ° C. on the surface of the core.