JPH0686362B2 - Method of heat evaporation of drug - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for heating and evaporating a drug.

2. Description of the Related Art As shown in Japanese Patent Publication No. 56-27481, a mat is impregnated with a chemical, and the mat is provided on a heating element composed of a plurality of independent heating members. A method in which the drug is evaporated by sequentially heating from one end.

As disclosed in JP-A-58-225001, a method in which partitions are provided at intervals in the longitudinal direction of a long tape and impregnated with a drug, and heating is performed while moving the tape to evaporate the drug. .

Problems to be Solved by the Invention In the former method, the mat impregnated with one drug is partially heated from the end, so that the heating is performed only for the time until all the drug impregnated in one part evaporates. For this reason, the temperature of not only a part but also the peripheral part is increased by heat conduction to accelerate the thermal decomposition of the drug, so that the medicinal effect of the drug at the time of heating and vaporizing the part is reduced.

Similarly, while heating and evaporating a part, drug migration and evaporation from the peripheral part occur, and extra drug evaporates. Therefore, the amount of drug evaporating when each part is evaporated and the drug The composition ratio is different.

Since a part having a certain area and volume is heated at the same time, it takes time to reach the air temperature at which the drug effect is expected to be poor at the start of use, that is, at the start of heating and evaporation.

With the latter method, even if a partition is provided on the tape, the adjacent compartments are also heated by the heat conduction of the aluminum foil on the back surface and some of the medicine evaporates, so the prescribed compartment, that is, the area between the adjacent compartments is heated and evaporated. It is difficult to accurately determine the amount of transpiration when performing.

Since the tape is always driven, a certain amount of a trace amount of the drug continues to evaporate, and the amount of the volatilized drug into the air is constantly low and constant, so that the insecticidal effect is low, and therefore, no effect can be expected for large pests.

In summary, both methods result in thermal decomposition of the drug in the part other than the part that is heat evaporated, and the amount of the drug volatilized into the air is always low.

Means and actions for solving the problem A method in which a small number of drugs are divided and arranged in large numbers, and the respective drugs are sequentially heated at predetermined time intervals and evaporated in an extremely short time As a result, the amount of drug in the air has a sawtooth shape with a peak value, and the heating time is short, so that thermal decomposition does not occur.

Example A large number of small scales 2 having a heat conducting portion 4 at the bottom are formed on a chemical carrier, for example, a transpiration plate 1, at intervals in the vertical direction X and the horizontal direction Y, and the chemicals 3 are respectively placed in the small holes 2. A plate-shaped evaporation plate in which the medicines are filled and the small amounts of the medicines are sectioned and separated are arranged.

The heating means, for example, the heating element 5 which is energized to generate heat has substantially the same size as the heat conducting portion 4, and is intermittently arranged along the evaporation plate 1 in the vertical direction X and the horizontal direction Y or in the vertical direction at predetermined intervals. As it moves, the medicine 3 in each small hole 2 is heated at every predetermined time and evaporated in an extremely short time.

Because of this, a large amount of the drug evaporates for an extremely short time, so that the amount of the drug evaporates to a constant high concentration in a short time every predetermined time as shown in FIG. As shown by the solid line in FIG. 5, it becomes a substantially sawtooth shape having a peak value at every predetermined time. In the conventional method, it is indicated by a chain line.

In FIG. 5, the dotted line indicates the amount of drug present in the air after the drug 3 in one small hole 2 evaporates.

Since the dose in the air increases in a very short time so as to have a peak amount, target pests and fungi that are ineffective at low concentrations can be killed and sterilized at the peak value.

Since the time for heating the drug 3 is extremely short and is short-term heating, the effect of thermal decomposition of the drug other than the heated drug part is high because the heating influence time is short and the drug is treated by the short-term heating. Since it spreads rapidly in space and becomes a high concentration, it has a high insecticidal effect with sufficient attachment of the drug before insects escape.

Further, at the start of heating and evaporation, the drug evaporates faster than before, so that the effect becomes high from the start of use.

Further, since the chemicals 3 in each small hole 2 are used by heating so as to be evaporated, stains, decomposed products, etc. during use remain as a residue in each small hole, and the chemicals in the next small hole are evaporated by heating. In this case, there is no influence of the above-mentioned stains and decomposed products, and a constant drug effect can be expected at all times, and similarly, a drug of a set type, amount and ratio can always be used.

Further, when a pyrethroid insecticide such as d-allethrin is used as a drug, the residual half-life of the insecticide evaporated into the air is about 2 hours, and therefore each insect is intermittently separated at intervals of 2 hours or less. There is a medicinal effect if the drug in the small hole is heated.

That is, it is sufficient to sequentially heat the drug in each small hole at a time interval shorter than the residual half-life in the case of evaporation into the air.

In addition, as the drug, insecticide, bactericide, insect repellent, repellent,
Any fragrance, pheromone, etc. that can be evaporated by heating may be used, and antioxidants, thermal decomposition inhibitors, pigments, fragrances, solvents, foaming agents, synergists, solidifying agents, adsorbents, etc. may be added to the above-mentioned main ingredients. It may be added.

The material of the drug carrier may be ceramic, polymer resin or the like as long as it has heat resistance, chemical resistance, and permeation resistance, and the shape may be polygonal, circular, elliptical, etc. The shape is also acceptable.

In addition, a porous material for holding a drug, a fiber or the like may be fixed in the drug partition portion of the drug holding plate to form a small hole, a coating may be formed, or a solidifying agent may be added. .

Further, the prescription of the medicine to be filled may be different for each small hole. For example, the dose may be changed according to the period of use of the mosquito according to the period of use of the mosquito, or the type, amount, and ratio of the drug may be changed by alternately volatilizing the knockdown drug and the KILL drug.

Further, as the heating means, a ceramic heating element, a thrust line, a heat beam, or the like may be used, and each partitioned drug is heated by contact, indirect contact, insertion, etc. regardless of the front and back sides of the drug carrier. May be. Also, it is possible to volatilize due to the increase of molecular motion similar to heating by ultrasonic vibration.

Further, the heating means may be fixed and the medicine holder may be moved to perform intermittent heating. The movement of the heating means or the medicine holder may be controlled by a microcomputer using a motor, a rack and pinion, a cylinder and the like.

Further, as shown in FIG. 8, the medicine 3 is put in the small hole 2 of the evaporation plate 1.
May be full so that both are flush with each other.

As shown in FIG. 9, the through holes 10 of the evaporation plate 1 are formed, and the bottom and the inner wall are made into the recesses 12 as the heat conducting parts 11, and the medicine 3 is put in the recesses 12 and heated from below. Alternatively, as shown in FIG. 10, heating-disappearing portions, for example, films 13 may be provided above and below the through hole 10 to heat from either the top or the bottom.

As shown in FIG. 11, a large number of porous portions 14 may be formed at intervals on the evaporation plate 1, and the porous portion 14 may be impregnated with the drug 3.

Also, as shown in Fig. 12, a stepped through hole with a small diameter at the top
15 may be formed, and the heat conducting portion 16 may be provided on the bottom thereof,
As shown in FIG. 13, films 18 and 18 may be provided on the entire upper and lower surfaces of the evaporation plate 1 having the through holes 17 to cover the medicine 3.

Also, as shown in FIG. 14, a hole that is spread downward in the evaporation plate 1
The impregnated body 20 may be formed by forming 19 and impregnated with a drug on the upper portion and heated from the bottom, or as shown in FIG.

Next, an example of an experiment in which a mosquito insecticide is used as a drug will be described.

In the apparatus shown in FIGS. 1 to 3, small holes 3 mm in diameter and 2.7 mm in depth, each having a heat conduction portion 4 having a diameter of 3 mm and a thickness of 0.3 mm at 6 mm intervals in a vaporization plate 1 having a size of 39 × 15 × 3 mm. Twelve 2
Put 3 mg of d-allethrin as an insecticide and 1 mg of BHT as an antioxidant in one small hole 2 and have a diameter of 3 mm and a length of 15 mm.
Then, the exothermic element 5 having a tip temperature of 180 ° C. was used to contact and drive the bottom of one small hole 2 every hour.

Here, since d-allethrin is used as an insecticide, 36 mg of d-allethrin is required when used for 8 hours in 8 tatami mats, and the amount of 3 mg is charged per hour, so 212 small holes are formed and each small hole is formed. 2 was charged with 3 mg d-allethrin.

Experiment 1 The device according to the present invention described above (hereinafter referred to as this product) and a mosquito repellent mat (22 × 35 × 2.8 mm pulp board / d-allethrin 36 m)
g, BHT12mg) is placed in each dedicated heating device and heated normally in 8 tatami mats, and after 50 minutes, 10 minutes, 30 minutes, 60 minutes, and 5 hours after energization, 50 Culex pipiens ♀ are released individually. 50% knockdown time (KT50 value) and mortality of the mosquito.

As a result, the results are shown in the table below.

From the above, the following was found.

Early use, especially about 10 minutes after power is turned on.
It was shortened to 1/10 and the rapid-acting performance was remarkably high.

The present invention has a high KT50 value and a high mortality rate from the beginning of use,
The mortality rate of the comparative product was more than doubled 10 minutes after the power was turned on.

After 5 hours of energization, the amount of d-allethrin in the air was high, and the mortality rate was higher than that of the comparative product.

Further, the amount of volatilized d-allethrin and the amount of d-allethrin in the air were measured respectively for this product and the comparative product, and FIG.
It became as shown in FIG.

EFFECTS OF THE INVENTION Since a high-concentration drug evaporates in an extremely short period of time at a predetermined time, the drug dose in the air shows a sawtooth-like increasing drug concentration having a peak value, and the drug dose in the air is extremely high in an extremely short time. Since it becomes higher, the target pests and fungi that are not effective at the average drug concentration at that time can be killed and sterilized.

The chemicals in each compartment are heated only for a short time, and the effect of heat on the chemicals in other compartments is short and the thermal decomposition prevention effect is high, and the chemicals rapidly spread to the usage space and become a high concentration. It has a high insecticidal effect because the drug adheres well before it escapes.

Since the drug evaporates immediately after the start of heating, it is highly effective from the start of use.

Since each compartment is heated for a short time, the decomposed product of dirt and the like remains as a residue in each compartment during use, so that when the medicine in the next compartment is heated, there is no effect of them and a constant drug effect is always obtained.

[Brief description of drawings]

Drawing shows an embodiment of the present invention, Fig. 1 is a perspective view of a drug holder, Fig. 2 is a front view, Fig. 3 is a front view in a heated state, and Fig. 4 is a chart showing the amount of drug transpiration. FIG. 5 is a chart showing the drug in the air, FIG. 6 is a chart showing the amount of transpiration of the drug, FIG. 7 is a diagram showing the amount of drug in the air, and FIGS. 8 to 15 show different examples of the evaporation plate. Sectional views, FIG. 16 and FIG. 17 are charts showing the amount of d-allethrin volatilized and the amount of d-allethrin in the air of this product and a comparative product according to Examples. 1 is a transpiration plate, 2 is a small hole, 3 is a drug, and 5 is a heat generating element.

Claims (1)

[Claims] 1. A method of heating a drug, characterized in that a small amount of the drug is divided into a large number and arranged, and the drug in each of the blocks is sequentially heated at a predetermined time interval to evaporate in an extremely short time. Transpiration method.