JP7482722B2 - Smoking method, smoking device, and smoking device unit - Google Patents

Description

The present invention relates to a smoking method, a smoking device, and a smoking device unit.

In general households, spaces such as inside houses and vehicles are treated with fumigants (fumigants) to control harmful organisms, such as microorganisms such as mold and bacteria, and sanitary pests such as flies, mosquitoes, and cockroaches. Fumigants include solid preparations containing an active ingredient such as a bactericidal ingredient or an insecticidal ingredient and a combustion base. When the fumigant is heated during use, the combustion base is burned or decomposed to generate smoke (gas and fine particles), and the active ingredient is volatilized into the air by the action of this smoke and heat. Therefore, the active ingredient is distributed throughout the entire space in a short time, and harmful organisms can be controlled.
To heat a fumigant, a direct heating method is used, in which a part of the fumigant is directly heated to burn it, or an indirect heating method is used, in which the fumigant is heated using the heat of reaction (heat of hydration reaction) between a heat generating agent such as calcium oxide and water.

In the indirect heating method, efforts are being made to shorten the time from when the heat generating agent comes into contact with water until smoking begins (smoking start time) compared to conventional methods.
Patent Document 1 discloses a technology in which at least one of the bottom wall and side wall of a sealed container that contains a heat generating agent is made water-permeable and the water-permeable wall is impregnated with a surfactant, thereby allowing water to quickly permeate the heat generating agent and achieving smooth heating.
Patent Document 2 discloses a technology for efficiently heating a fumigant and quickly starting smoking by devising a container shape and molding a heat generating agent.

JP 2004-350688 A JP 2000-60405 A

However, with the fumigation start time used in conventional indirect heating methods and the technologies of Patent Documents 1 and 2, when fumigating narrow spaces such as under the floors of buildings where it is difficult for workers to evacuate, or large spaces such as large warehouses where large amounts of fumigant are used at once, there is a risk that smoke will start while workers are evacuating or working, making it difficult to ensure the safety of the workers.
One aspect of the present invention aims to provide an indirect heating type fumigation method, a fumigation device, and a fumigation device unit that can delay the start of fumigation.

The present invention has the following aspects.
[1] A method for smoking using an indirect heating method, comprising contacting a liquid (A) containing water with calcium oxide and heating a fumigant by the heat of reaction between the water and the calcium oxide,
The liquid (A) contains one or more smoke initiation retardants (B) selected from the group consisting of polymer compounds (B1) and nonionic surfactants (B2);
A fumigation method, wherein the viscosity of the liquid (A) at 25°C is 3.5 to 30 mPa·s.
[2] The fumigation method according to [1], wherein the polymer compound (B1) is one or more selected from the group consisting of xanthan gum and polyvinyl alcohol.
[3] The fumigation method of [1] or [2], wherein the nonionic surfactant (B2) is one or more selected from the group consisting of polyoxyethylene alkyl ether type nonionic surfactants and alkylamine oxide type nonionic surfactants.
[4] The fumigation method according to any one of [1] to [3], wherein the nonionic surfactant (B2) is a polyoxyethylene alkyl ether type nonionic surfactant having a branched alkyl group.
[5] A smoking device of an indirect heating type, comprising: a cylindrical outer container with a bottom; and a cylindrical inner container with a bottom that is disposed within the outer container and has a water-permeable bottom; within the inner container, a heating section filled with calcium oxide and a heated section filled with a smoking agent are disposed via a heat transfer section; water is stored in the outer container, and the smoking agent is heated by the heat of reaction between the water and the calcium oxide;
One or more smoke initiation retardants (B) selected from the group consisting of polymer compounds (B1) and nonionic surfactants (B2) are attached to the portion of the outer container in which water is stored,
A smoking device in which the amount of the fumigation initiation retardant (B) attached to the portion of the outer container is an amount such that the viscosity of a liquid obtained by mixing the water stored in the outer container and the fumigation initiation retardant (B) at 25°C is 3.5 to 30 mPa·s.
[6] A smoking device of an indirect heating type in which a heating section filled with calcium oxide and a heated section filled with a smoking agent are provided via a heat transfer section, the calcium oxide reacts with water, and the smoking agent is heated by the reaction heat;
A liquid (A) containing water and one or more smoke initiation retardants (B) selected from the group consisting of a polymer compound (B1) and a nonionic surfactant (B2);
A smoke device unit comprising:

According to one aspect of the present invention, it is possible to provide an indirect heating type fumigation method, a fumigation device, and a fumigation device unit that can delay the start of fumigation.

FIG. 1 is a schematic cross-sectional view showing an example of a smoking device. FIG. 2 is a schematic cross-sectional view showing another example of a smoking device.

[Smoking method]
A fumigation method according to one embodiment of the present invention is an indirect heating method in which a water-containing liquid (A) is brought into contact with calcium oxide and the fumigant is heated by the heat of reaction between the water and calcium oxide.
Liquid (A) contains water and one or more fumigation initiation retardants (B) (hereinafter also referred to as "component (B)") selected from the group consisting of polymeric compounds (B1) and nonionic surfactants (B2). Liquid (A) may further contain other components as necessary. Liquid (A) has a viscosity of 3.5 to 30 mPa·s at 25°C.

When liquid (A) is brought into contact with calcium oxide, the water in liquid (A) reacts with the calcium oxide, generating reaction heat (hydration reaction heat).
The method for contacting liquid (A) with calcium oxide is not particularly limited, but examples include a method in which water and component (B) are mixed in advance to prepare liquid (A) and this liquid (A) is supplied to a smoking device used to heat the smoking agent (Method 1), and a method in which component (B) is attached in advance to a portion of the smoking device used to heat the smoking agent that will come into contact with water (a specified inner surface of the outer container or the bottom of the inner container described below) and water is supplied to the smoking device (Method 2).
A smoking device used to heat a smoking agent typically includes a heating section filled with calcium oxide, a heated section filled with a smoking agent, and a heat transfer section separating the heating section from the heated section, and a liquid supplied to the smoking device is introduced into the heating section. When the liquid is introduced into the heating section, the water in the liquid reacts with the calcium oxide, and the heat of reaction is transferred to the heated section via the heat transfer section to heat the smoking agent.

The mass ratio of calcium oxide to liquid (A) [calcium oxide/liquid (A)] is preferably 0.5 to 5.0, and more preferably 1.0 to 4.5. If the mass ratio of calcium oxide to liquid (A) is equal to or greater than the lower limit, it is easy to obtain a sufficient amount of heat to generate smoke from the fumigation agent, and if it is equal to or less than the upper limit, abnormal reactions such as bumping are unlikely to occur.

The mass ratio of calcium oxide to the fumigant [calcium oxide/fumigant] is preferably 2.0 to 15.0, and more preferably 4.0 to 13.0. If the mass ratio of calcium oxide to the fumigant is equal to or greater than the lower limit, it is easy to obtain a sufficient amount of heat to cause the fumigant to smoke, and if it is equal to or less than the upper limit, abnormal reactions such as bumping are unlikely to occur.

<Water>
The water is not particularly limited, and may be ion-exchanged water, distilled water, tap water, etc. Tap water is preferred because it is easily available.
The content of water is the remainder after subtracting component (B) and other components from liquid (A).

<Component (B)>
The component (B) is at least one member selected from the group consisting of a polymeric compound (B1) (hereinafter also referred to as “component (B1)”) and a nonionic surfactant (B2) (hereinafter also referred to as “component (B2)”).
Component (B) has the effect of increasing the viscosity of liquid (A) and delaying the onset of smoking. By including component (B) in liquid (A) such that the viscosity at 25°C is 3.5 to 30 mPa·s, the onset of smoking can be delayed, allowing safe operation when smoking a narrow or wide space.

The component (B1) is preferably a water-soluble polymer compound. When dissolved in water, the water-soluble polymer compound forms a hydrogel with a large amount of water surrounding the molecules, and has the effect of significantly increasing the viscosity of the aqueous solution.
"Water-soluble" means that the solubility in 1 L of water at 25°C is 0.1 g or more.

Examples of component (B1) include natural polymer compounds such as xanthan gum and quince seed gum; semi-synthetic polymer compounds such as carboxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, and cellulose nanofiber; and synthetic polymer compounds such as polyvinyl alcohol, carboxyvinyl polymer, and sodium polyacrylate. Among these, xanthan gum, methyl cellulose, polyvinyl alcohol, sodium polyacrylate, cellulose nanofiber, and carboxyvinyl polymer are preferred in terms of excellent viscosity controllability, with xanthan gum and polyvinyl alcohol being particularly preferred.

The molecular weight of component (B1) is preferably 10,000 or more, and more preferably 100,000 or more. The upper limit of the molecular weight of component (B1) is, for example, 1,000,000. The molecular weight is the weight average molecular weight measured by gel permeation chromatography (GPC).

Examples of the (B2) component include polyoxyethylene (hereinafter also referred to as "POE") alkyl ether type nonionic surfactants, sorbitan fatty acid ester type nonionic surfactants, glycerin fatty acid ester type nonionic surfactants, polyglycerin fatty acid ester type nonionic surfactants, sucrose fatty acid ester type nonionic surfactants, propylene glycol fatty acid ester type nonionic surfactants, glycerin alkyl ether type nonionic surfactants, alkylamine oxide type nonionic surfactants, POE-sorbitan fatty acid ester type nonionic surfactants, POE-glycerin fatty acid ester type nonionic surfactants, POE-propylene glycol fatty acid ester type nonionic surfactants, POE-polyoxypropylene (hereinafter also referred to as "POP") alkyl ether type nonionic surfactants, alkanolamide type nonionic surfactants, and copolymer type nonionic surfactants of oxypropylene and oxyethylene.

As the component (B2), among the above, POE alkyl ether type nonionic surfactants, alkylamine oxide type nonionic surfactants, and sorbitan fatty acid ester type nonionic surfactants are preferred in terms of excellent solubility in water, and POE alkyl ether type nonionic surfactants and alkylamine oxide type nonionic surfactants are more preferred. Among these, POE alkyl ether type nonionic surfactants having a branched alkyl group are preferred in terms of excellent smoke retardation effect.
The number of carbon atoms in the alkyl group of the POE alkyl ether type nonionic surfactant is, for example, 8 to 20. The average number of repetitions of the oxyalkylene group in the POE is, for example, 6 to 40.

The content of component (B) in liquid (A) is set so that the viscosity of liquid (A) at 25° C. is 3.5 to 30 mPa·s.
When the (B) component is the (B1) component, the content of the (B1) component is preferably 0.005 to 1.0% by mass, more preferably 0.01 to 0.5% by mass, based on the total mass of the liquid (A). By having the (B1) component content within the above range, the viscosity characteristics of the liquid (A) tend to fall within a preferred range, and an excellent smoke start delay effect tends to be obtained.
When the (B) component is the (B2) component, the content of the (B2) component is preferably 2.0 to 15.0% by mass, more preferably 4.0 to 10.0% by mass, based on the total mass of the liquid (A). By setting the content of the (B2) component within the above range, the viscosity characteristics of the liquid (A) tend to be in a preferred range, and an excellent smoke start delay effect tends to be obtained.

<Other Ingredients>
Examples of other ingredients include fragrances, preservatives, colorants, and antibacterial agents. Two or more of these ingredients may be used in combination.
The content of the other components in the liquid (A) is, for example, 0 to 10 mass % relative to the total mass of the liquid (A).

<Viscosity>
The viscosity of liquid (A) at 25°C is 3.5 to 30 mPa·s, preferably 4.5 to 30 mPa·s, and more preferably 5.5 to 30 mPa·s. If the viscosity of liquid (A) is 3.5 mPa·s or more, it has an excellent effect of delaying the start of smoking. It also has an excellent volatilization rate of the smoking agent, and can suppress clogging of the lid of the smoking device during smoking. In particular, if it is 5.5 mPa·s or more, it can suppress the burnt odor during smoking. If the viscosity of liquid (A) is 30 mPa·s or less, liquid (A) easily penetrates calcium oxide, and it is easy to obtain sufficient reaction heat to cause the smoking agent to smoke.
The "viscosity" is a value measured by a Brookfield viscometer. Detailed measurement conditions are shown in the Examples section below.

<Calcium oxide>
Calcium oxide is a heat generating agent that generates heat by reacting with water (hydration reaction). The temperature of the heat of reaction between water and calcium oxide is about 250°C to about 400°C.
The calcium oxide may be in the form of granules, powder, lumps, or the like.
The bulk density of calcium oxide at 20° C. is preferably 0.50 to 1.0 g/cm ³ .
The average particle size of calcium oxide is preferably 1.0 to 5.0 mm. The average particle size is measured by a sieve method.

<Fumigants>
The fumigating agent may be any agent capable of being smoked by heating using an indirect heating method, and any known fumigating agent used for the control of harmful organisms such as microorganisms and sanitary pests may be used.
An example of a fumigant is one that contains an organic foaming agent and a microbial control agent. This fumigant preferably further contains a surfactant in order to enhance the microbial control effect. This fumigant may further contain components other than the organic foaming agent, the microbial control agent, and the surfactant (hereinafter, also referred to as "optional components").

(Organic foaming agent)
The organic foaming agent is a component that decomposes when heated to generate a large amount of heat and also generates carbon dioxide gas, nitrogen gas, etc. (hereinafter, these are collectively referred to as "foaming gas"), and functions as a combustion base material.
Examples of organic foaming agents include azodicarbonamide, p,p'-oxybis(benzenesulfonylhydrazide), N,N'-dinitrosopentamethylenetetramine, azobisisobutyronitrile, etc. Among these, azodicarbonamide is preferred from the viewpoints of decomposition temperature, amount of foaming gas generated, etc.
The organic foaming agent may be used alone or in combination of two or more kinds.

The content of the organic foaming agent can be determined taking into consideration the type of organic foaming agent and other components. Specifically, the content of the organic foaming agent is preferably 50 to 90 mass % of the total mass of the fumigating agent, and more preferably 60 to 85 mass %. When the content of the organic foaming agent is equal to or greater than the lower limit, the microbial control agent is efficiently converted into smoke and easily volatilized. When the content of the organic foaming agent is equal to or less than the upper limit, the amount of decomposition products of the organic foaming agent scattered is reduced, making it less likely to contaminate the space to be treated (target space).

(Microbial control agent)
The microbial control agent is a component that exerts a microbial control effect and a deodorizing effect against odors caused by microorganisms, and functions as an active ingredient of a fumigant.
Examples of microbial control agents include silver-based agents and organic agents used in conventional disinfectants, bactericides, antibacterial agents, antifungal agents, antifungal agents, etc. The silver-based agents and organic agents may be used alone or in combination of two or more types.

Silver-based drugs contain silver or a silver compound as an active ingredient. Silver has a bactericidal, germicidal, antibacterial, antifungal, antifungal or deodorizing effect. Examples of silver compounds include silver oxide; inorganic silver salts such as silver chloride, silver nitrate, silver sulfate, silver carbonate, and silver sulfonate; and organic silver salts such as silver formate and silver acetate.
As the silver-based agent, a support in which the above-mentioned silver compound is supported on a substance such as zeolite, silica gel, low molecular weight glass, calcium phosphate, silicate, titanium oxide, etc. (hereinafter, also referred to as "support") may be used. Examples of the support include zeolite-based antibacterial agents, silica gel-based antibacterial agents, titanium oxide-based antibacterial agents, and silicate-based antibacterial agents, each supporting a silver compound such as simple silver or silver oxide, inorganic silver salt, or organic silver salt.

Among the above, as the silver-based agent, from the viewpoint of further reducing the odor derived from the microbial control agent, silver alone, inorganic silver salts such as silver oxide and silver nitrate, or supports in which these are supported on a carrier are preferred. In particular, zeolite-based antibacterial agents supporting silver compounds such as silver alone, inorganic silver salts such as silver oxide and silver nitrate are preferred.
The silver-based agent may be used alone or in combination of two or more kinds.

The content of the silver-based agent is preferably an amount that results in a silver concentration of 0.001 to 0.5% by mass, more preferably 0.05 to 0.1% by mass, relative to the total mass of the fumigant. When the silver concentration is equal to or greater than the lower limit, the microbial control effect and deodorizing effect are sufficient. If the silver concentration exceeds the upper limit, the microbial control effect and deodorizing effect saturate, and the cost is simply increased. In addition, if the silver concentration exceeds the upper limit, the content of other components in the fumigant becomes relatively low, and there is a risk of a decrease in the volatilization rate of the microbial control agent.

Examples of organic agents include 3-methyl-4-isopropylphenol (IPMP), 3-iodo-2-propynyl butylcarbamate (IPBC), didecyldimethylammonium chloride, o-phenylphenol (OPP), sodium benzoate, glutaraldehyde, polyhexamethylene biguanidine hydrochloride, etc. Among these, from the viewpoint of microbial control effect, IPMP, IPBC, and didecyldimethylammonium chloride are preferred, and IPMP is more preferred.
The organic agent may be used alone or in combination of two or more kinds.

The content of the organic agent is preferably 1 to 30% by mass, more preferably 1 to 20% by mass, based on the total mass of the fumigant. When the content of the organic agent is equal to or greater than the lower limit, the microbial control effect and deodorizing effect are sufficient. If the content of the organic agent exceeds the upper limit, the microbial control effect and deodorizing effect saturate, and the cost is simply increased. In addition, if the content of the organic agent exceeds the upper limit, the content of other components in the fumigant becomes relatively low, and there is a risk of a decrease in the volatilization rate of the microbial control agent.

(Surfactant)
When the fumigant contains a surfactant, the microbial control effect is enhanced because the surfactant facilitates the penetration of the microbial control agent into the microorganisms when the surface to be treated has a certain amount of moisture.
The surfactant is preferably a nonionic surfactant, and more preferably a nonionic surfactant having an HLB of 7 to 15 as determined by the Davis method.

Examples of the nonionic surfactant include a triblock surfactant represented by the following formula (1) and a sorbitan fatty acid ester surfactant.
R ¹ -O-(PO) _f -(EO) _g -(PO) _h -R ² ... (1)
In formula (1), ^R1 and ^R2 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, PO is an oxypropylene group, EO is an oxyethylene group, f represents the average number of repeats of PO and is a number from 5 to 150, g represents the average number of repeats of EO and is a number from 5 to 250, and h represents the average number of repeats of PO and is a number from 5 to 150.

Each of R ¹ and R ² is preferably a hydrogen atom.
It is preferable that f is a number from 10 to 30.
g is preferably a number from 5 to 30.
h is preferably a number from 10 to 30.
The value of f+g+h is preferably a number from 20 to 500.

Examples of commercially available surfactants include "Pluronic RPE1720", "Pluronic RPE1740", and "Pluronic RPE2520" manufactured by BASF Japan Ltd.; and "Emersol L-10V", "Emersol O-10V", and "Emersol S-10V" manufactured by Kao Corporation.
The surfactant may be used alone or in combination of two or more kinds.

The surfactant content is preferably 1 to 15% by mass, more preferably 5 to 12% by mass, based on the total mass of the fumigant. If the surfactant content is within the above range, the microbial control effect is further enhanced.

(Optional ingredients)
Optional components include, for example, binders, excipients, heat generating agents, stabilizers, efficacy enhancers, antioxidants, fragrances, and solvents.

Examples of binders include cellulose-based compounds (methyl cellulose, ethyl cellulose, carboxymethyl cellulose and its calcium salts and sodium salts, hydroxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose, etc.), starch-based compounds (starch, pregelatinized starch, dextrin, hydroxypropyl starch, carboxymethyl starch sodium salt, etc.), natural product-based compounds (gum arabic, sodium alginate, tragacanth, gelatin, etc.), and synthetic polymer-based compounds (polyvinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate, etc.).
Examples of excipients include inorganic minerals (clay, kaolin, talc, quartz, crystal, etc.).
Examples of the heat generating assistant include zinc oxide, calcium phosphate, and melamine.
Examples of the stabilizer include dibutylhydroxytoluene, butylhydroxyanisole, propyl gallate (propyl-3,4,5-trihydroxybenzoate), and epoxy compounds (epoxidized soybean oil, epoxidized linseed oil, etc.).
Potency enhancers include, for example, piperonyl butoxide (5-[2-(2-butoxyethoxy)ethoxymethyl]-6-propyl-1,3-benzodioxole) and S-421 (di(2,3,3,3-tetrachloropropyl)ether).
Examples of the antioxidant include dibutylhydroxytoluene (BHT) and tocopherol.
The flavoring agent includes, for example, various flavors.
Examples of the solvent include water and monohydric alcohols (ethanol, propanol, butanol, etc.).
These optional components may be used alone or in combination of two or more.

(Method of manufacturing fumigants)
Fumigants are prepared as solid formulations such as powders, granules, tablets, etc., or as liquid formulations.
The method for producing the fumigant is a known method depending on the desired formulation. For example, when a granular preparation is used, the organic foaming agent and the microbial control agent, and optionally one or more of the surfactant and optional components are mixed and granulated. As the granulation method, known granulation methods such as extrusion granulation, compression granulation, stirring granulation, rolling granulation, and fluidized bed granulation are used. When a liquid preparation is used, the respective components are mixed and dissolved or dispersed.

A specific example of a production method using extrusion granulation is a method in which an organic foaming agent and a microbial control agent are mixed with one or more surfactants and optional components as required in a kneader or the like, an appropriate amount of water is added as required, and the resulting mixture is granulated in a forward extrusion or horizontal extrusion granulator using a die having a desired opening size. The granulated product may be further cut into a desired size with a cutter or the like, and dried to remove moisture.
The drying method may be, for example, a heat drying method using a conventionally known dryer. The drying temperature is not particularly limited, but is preferably 50 to 80° C. from the viewpoint of suppressing the volatilization of the fragrance, etc. The drying time is appropriately determined depending on the drying temperature.

The moisture content of the fumigant after drying is not particularly limited, but is preferably 5% by mass or less, more preferably 2% by mass or less, and may be 0% by mass, based on the total mass of the fumigant. If the moisture content is equal to or less than the above upper limit, the volatilization rate of the microbial control agent is easily improved.
The moisture content can be measured, for example, by grinding the dried fumigant and measuring it with a moisture meter at 105° C. for 20 minutes. An example of the moisture meter is the “MOC-120H” moisture meter manufactured by Shimadzu Corporation.

Hereinafter, an embodiment of the fumigation method according to the present invention will be described in detail with reference to the drawings.
In addition, in each drawing used in the following description, the dimensional ratio of each component may differ from the actual one.

First Embodiment
In the fumigation method according to the first embodiment, a fumigation device unit including the fumigation device 1 shown in FIG. 1 and a liquid (A) is used.
The liquid (A) is as described above. The liquid (A) is typically contained in a container.

(Smoking device)
The smoking device 1 shown in FIG. 1 comprises a cylindrical outer container 10 with a bottom, and a cylindrical inner container 20 with a bottom that is provided inside the outer container 10 and has a water-permeable bottom 24.

The outer container 10 is generally composed of a cylindrical peripheral wall portion 12 and a bottom portion 14 .
Four rectangular parallelepiped protrusions 15 are arranged at 90° intervals on the inner bottom surface 14a of the bottom portion 14.

The size of the outer container 10 is determined according to the amount of fumigant used and the size of the inner container 20, etc. For home use with a floor area of the space to be treated of about 6.5 to ³⁰ m2, the height of the outer container 10 is set to 40 to 120 mm and the inner diameter of the outer container 10 is set to 55 to 100 mm, for example. For large-scale warehouse use with a floor area of the space to be treated of about 30 to ³⁰⁰ m2, the height of the outer container 10 is set to 100 to 150 mm and the inner diameter of the outer container 10 is set to 80 to 150 mm, for example.

The material of the outer container 10 may be any material that is at least water resistant, such as plastic or paper. The thickness of the outer container 10 can be determined taking into account strength and other factors, and is, for example, 0.5 to 10 mm.

The inner container 20 is generally composed of a cylindrical side wall portion 22 and a bottom portion 24 .
The outer circumferential surface 22 b of the inner container 20 is spaced apart from the inner circumferential surface 12 a of the outer container 10 .
A heating section 30 and a heated section 40 are provided within the inner container 20 via a heat transfer section 50. The heating section 30 is formed by filling the inner container 20 with calcium oxide.

The heat transfer section 50 is a cylindrical member with a bottom, and is provided within the inner container 20 so that a portion of the heat transfer section 50 is embedded in the heating section 30. The heat transfer section 50 is filled with a fumigant to form the heated section 40.
An upper end 50c of the heat transfer section 50 and an upper end 22c of the side wall section 22 are connected by a connecting member 26, and the space between the inner container 20 and the heat transfer section 50 at the upper end surface 20e is closed by the connecting member 26. The connecting member 26 is also provided with an air hole 26a which serves as an escape hole for steam generated during the reaction between the exothermic agent and water.
A lid 60 is provided near an upper end surface 50 e of the heat transfer portion 50 .

The heat transfer section 50 is smaller than the inner container 20, and is provided so that its upper end surface 50e is flush with the upper end surface 20e of the inner container 20. That is, the inner circumferential surface 22a of the inner container 20 is spaced apart from the outer circumferential surface 50b of the heat transfer section 50, and the bottom 24 of the inner container 20 is spaced apart from the bottom 54 of the heat transfer section 50. Calcium oxide is filled between the inner container 20 and the heat transfer section 50. The distance between the bottom 24 of the inner container 20 and the bottom 54 of the heat transfer section 50 is preferably 10 to 18 mm, and more preferably 12 to 14 mm.

The size of the inner container 20 is determined according to the amount of fumigant to be used, etc. For household use with a floor area of the space to be treated of approximately 6.5 to 30 m2, for example, the height of the inner container 20 is 30 to 110 mm, and the outer diameter of the inner container 20 is 45 to 90 mm.

In the smoking device 1, it is preferable that the outer peripheral surface 22b and the inner peripheral surface 12a are spaced apart by at least 7 mm. If the distance between the two is less than 7 mm, there is a risk that the outer container 10 will become too hot during smoking. If the distance between the outer peripheral surface 22b and the inner peripheral surface 12a is 15 mm or less, the ejection force of the fumigant from the inner container 20 due to heating will be stronger, and the volatility of the active ingredient will tend to be better.

The bottom 24 of the inner container 20 in this example is made of a water-permeable bottom plate 241 in which a water-permeable material 241c is placed on a plate 241b having a water-passing hole 241a. The water-permeable material 241c is preferably placed so as to cover almost the entire surface of the plate 241b, and in particular, the bottom 24 is preferably a water-permeable bottom plate in which the water-permeable material 241c is fixed to the plate 241b by crimping. If the bottom 24 is a water-permeable bottom plate 241 in which the water-permeable material 241c is fixed to the plate 241b by crimping, it is possible to prevent the position of the water-permeable material 241c from shifting or rolling up on the bottom 24. This makes it less likely that there will be variation in the time at which smoking will begin, and also makes it easier to mechanize the packaging process.
The method of crimping and fixing the water-permeable material 241c to the plate 241b is not particularly limited, and examples thereof include the method described in JP-A-2001-247407. For example, a metal circular plate having a water passage hole for water passage is further drilled at several locations (preferably 4 locations or more, more preferably 6 to 8 locations), preferably at positions closer to the outer circumference than the water passage hole for water passage, more preferably at symmetrical positions, on the back side of the metal plate when drilling holes, preferably so that two or more protrusions are generated per hole. Then, a water-permeable material is placed on the surface with the protrusions and pressed. Then, the protrusions fall sideways and are crushed, and the water-permeable material is fixed to the metal plate.

The plate 241b is preferably a metal plate such as tinplate, steel plate, or aluminum plate.
As the water-permeable material 241c, nonwoven fabric or filter paper having high water permeability is preferable, and examples thereof include nonwoven fabric made of synthetic fibers such as polyolefin (polyethylene, polypropylene, etc.), nylon, polyester, etc., or these synthetic fibers combined with cotton, rayon, etc.; nonwoven fabric or filter paper made of glass fiber; cellulose-based filter paper, etc. Among them, nonwoven fabric containing a large amount of rayon is preferable because it has high water permeability and is stronger than cellulose-based filter paper, etc.

The material of the sidewall 22 is heat-resistant so that it will not deform due to the heat generated by the heating section 30, and examples of such materials include metal, ceramics, and paper. The thickness of each of the sidewall 22 and bottom 24 can be determined taking into consideration the required strength, heat resistance, etc. For example, the thickness of the sidewall 22 is 0.1 to 5 mm, and the thickness of the bottom 24 is 0.1 to 5 mm.

The heat transfer section 50 functions as a container for filling with the fumigant, and also has the function of transferring the thermal energy generated in the heating section 30 to the heated section 40 .
The material of the heat transfer portion 50 may be any material having heat conductivity, and is preferably metal. The thickness of the heat transfer portion 50 can be determined taking into consideration the heat conductivity, and is set to, for example, 0.1 to 5 mm.

The size of the heat transfer section 50 is determined according to the amount of fumigant. For home use with a floor area of the space to be treated of about 6.5 to ³⁰ m2, the height of the members constituting the heat transfer section 50 (the distance between the bottom 54 and the upper end surface 50e) is 10 to 80 mm, and the outer diameter of the members is 40 to 85 mm. For large-scale warehouse use with a floor area of the space to be treated of about ³⁰ to 300 m2, the height of the members constituting the heat transfer section 50 is 50 to 200 mm, and the outer diameter of the members is 70 to 220 mm.

The lid 60 has holes through which the fumigant vapor passes, and examples of the lid include a mesh, punched metal, and a lattice-shaped frame.
The material of the lid 60 is heat-resistant so as not to be deformed by the high-temperature steam generated from the heated portion 40, and examples of the material include metal, ceramics, and paper.

(Smoking method)
The fumigation method of this embodiment using the above-mentioned fumigation device unit will be described. The fumigation method of this embodiment corresponds to the above-mentioned method 1.
First, liquid (A) is poured into the outer container 10 of the smoking device 1. Next, the outer container 10 containing the liquid (A) is placed in the target space, and the inner container 20 is placed on the protrusion 15 of the outer container 10 so that the bottom 24 of the inner container 20 is immersed in the liquid (A).
When the inner container 20 is placed, the water in the liquid (A) that has entered the inner container 20 from the bottom 24 undergoes a hydration reaction with calcium oxide in the heating section 30, generating heat. This heat is transferred to the fumigant through the peripheral and bottom walls of the heat transfer section 50, and the temperature of the fumigant rises and it evaporates. In other words, the combustion base vaporizes, and the active ingredient diffuses through the holes in the lid 60 together with this vapor.

The amount of liquid (A) to be placed in the outer container 10 must be at least an amount sufficient to immerse the bottom 24 of the inner container 20 in the liquid (A), but from the viewpoint of increasing heat generation efficiency, it is preferable that the amount is as small as possible. This can be determined appropriately taking into consideration the mass ratio of calcium oxide to liquid (A) [calcium oxide/liquid (A)], etc.
As described above, the mass ratio of calcium oxide to the liquid (A) is preferably from 0.5 to 5.0, and more preferably from 1.0 to 4.5.

The heating temperature, heating rate and holding time of the fumigant may be appropriately set according to the type of active ingredient. The heating temperature, heating rate and holding time can be controlled by selecting the mass ratio of calcium oxide to liquid (A), the amount of calcium oxide used, the product grade of calcium oxide and the particle size of calcium oxide. The mass ratio of calcium oxide to liquid (A) may be appropriately determined taking into consideration the color depth of the smoke-like matter generated, the amount of smoke-like matter generated, the duration of smoking, the amount of volatilization of the active ingredient, etc. It can also be controlled by the capacity or material of the member constituting the heat transfer section 50 in which the fumigant is filled.
In addition, the start of smoking can be delayed by extending the time it takes to reach a heating temperature sufficient for volatilization (for example, 190°C or higher). Delaying the start of smoking results in a milder volatilization state, improved volatilization rate, less burning of smoke residue and improved odor, and reduced clogging of the lid (60 in Figure 1).

The heating temperature of the fumigant is preferably 150 to 450°C, more preferably 170 to 400°C, and even more preferably 190 to 400°C. By heating at 150°C or higher, the generated vapor of the combustion base can be ejected in the form of smoke, and the active ingredient can be diffused throughout the target space in a short period of time. Within this heating temperature range, the higher the heating temperature, the shorter the time it takes for the active ingredient to diffuse throughout the target space, and the wider the range of diffusion. If the heating temperature exceeds 450°C, the active ingredient may be thermally decomposed, and the amount that volatilizes in an effective (undecomposed) state may decrease (volatilization efficiency may decrease).

Second Embodiment
In the fumigation method according to the second embodiment, a fumigation device 1A is used.

(Smoking device)
The smoking device 1A used in this embodiment is the same as the smoking device 1 shown in Fig. 1 except that the component (B) is attached to the portion of the outer container 10 where water is stored (hereinafter also referred to as the "predetermined inner surface of the outer container"). Other components may be attached to the predetermined inner surface of the outer container as necessary.
Here, the portion of the outer container 10 in which water is stored refers to the inner bottom surface 14a of the bottom 14 of the outer container 10 and the portion of the inner circumferential surface 12a of the peripheral wall portion 12 of the outer container 10 that comes into contact with water.
When water is poured into the outer container 10, the water stored in the outer container 10 mixes with the component (B) and the like to become liquid (A).
The component (B) and other components are as described above.
In the second embodiment, from the standpoint of smoke retardation, it is preferred that the (B) component be the (B2) component.

The amount of component (B) attached to a predetermined inner surface of outer container 10 is an amount that makes the viscosity of the liquid, a mixture of water and component (B) stored in outer container 10, of 3.5 to 30 mPa·s at 25°C.
The preferred viscosity of the liquid obtained by mixing water and component (B) stored in the outer container 10 is the same as the preferred viscosity of the liquid (A) described above.

Taking into consideration the possibility that component (B) adhering to a specific inner surface of the outer container 10 may come off before the smoking device 1A is used, component (B) may be adhered to a specific inner surface of the outer container 10 in an amount in excess of the theoretical amount. The theoretical amount is the amount that will produce a liquid with the desired viscosity when that amount of component (B) is mixed with the amount of water to be placed in the outer container.

When the component (B) is the component (B1), when the water contained in the outer container 10 and the component (B), etc. are mixed to form the liquid (A), the content of the component (B1) relative to the total mass of the liquid (A) is preferably 0.005 to 1.0 mass%, and more preferably 0.01 to 0.5 mass%.
When the (B) component is the (B2) component, when the water contained in the outer container 10 and the (B) component, etc. are mixed to form the liquid (A), the content of the (B2) component relative to the total mass of the liquid (A) is preferably 2.0 to 15.0 mass%, and more preferably 4.0 to 10.0 mass%.

(Smoking method)
A smoking method according to the present embodiment using the smoking device 1A will be described. The smoking method according to the present embodiment corresponds to the above-mentioned method 2.
First, water is poured into the outer container 10 of the smoking device 1A. At this time, the (B) component and the like attached to a specific inner surface of the outer container 10 mix with the water to obtain liquid (A). Next, the outer container 10 containing water is placed in the target space, and the inner container 20 is placed on the protrusion 15 of the outer container 10 so that the bottom 24 of the inner container 20 is immersed in the liquid (A).
When the inner container 20 is placed, the water in the liquid (A) that has entered the inner container 20 from the bottom 24 undergoes a hydration reaction with calcium oxide in the heating section 30, generating heat. This heat is transferred to the fumigant through the peripheral and bottom walls of the heat transfer section 50, and the temperature of the fumigant rises and it evaporates. In other words, the combustion base vaporizes, and the active ingredient diffuses through the holes in the lid 60 together with this vapor.
The amount of water put into the outer container 10 and the heating temperature of the fumigant are similar to the amount of liquid (A) put into the outer container 10 and the heating temperature of the fumigant in the fumigation method of the first embodiment.

Third Embodiment
In the fumigation method according to the third embodiment, a fumigation device 1B is used.

(Smoking device)
The smoking device 1B used in this embodiment is similar to the smoking device 1 shown in Fig. 1 except that the component (B) is attached to the bottom 24 of the inner container 20. Other components may be attached to the bottom 24 of the inner container 20 as necessary.

The amount of component (B) attached to bottom 24 of inner container 20 is an amount that makes the viscosity of the liquid mixture of water and component (B) stored in outer container 10 at 25° C. 3.5 to 30 mPa·s.
The preferred viscosity of the liquid obtained by mixing water and component (B) stored in the outer container 10 is the same as the preferred viscosity of the liquid (A) described above.

Taking into consideration the possibility that component (B) adhering to the bottom 24 of the inner container 20 may be lost before the smoking device 1B is used, component (B) may be adhered to the bottom 24 of the inner container 20 in excess of the theoretical amount.

When the component (B) is the component (B1), when the water contained in the outer container 10 and the component (B), etc. are mixed to form the liquid (A), the content of the component (B1) relative to the total mass of the liquid (A) is preferably 0.005 to 1.0 mass%, and more preferably 0.01 to 0.5 mass%.
When the (B) component is the (B2) component, when the water contained in the outer container 10 and the (B) component, etc. are mixed to form the liquid (A), the content of the (B2) component relative to the total mass of the liquid (A) is preferably 2.0 to 15.0 mass%, and more preferably 4.0 to 10.0 mass%.

(Smoking method)
A smoking method of this embodiment using the smoking device 1B will be described. The smoking method of this embodiment corresponds to the above-mentioned method 2.
First, water is poured into the outer container 10 of the smoking device 1B. Next, the outer container 10 containing the water is placed in the target space, and the inner container 20 is placed on the protrusion 15 of the outer container 10 so that the bottom 24 of the inner container 20 is immersed in the liquid (A). At this time, the (B) component and the like attached to the bottom 24 of the inner container 20 mix with the water, and liquid (A) is obtained.
When the inner container 20 is placed, the (B) component and other components adhering to the bottom 24 of the inner container 20 mix with water to obtain liquid (A). This liquid (A) penetrates into the inner container 20 from the bottom 24. The water in the penetrated liquid (A) undergoes a hydration reaction with calcium oxide in the heating section 30, generating heat. This heat is transferred to the fumigant through the peripheral and bottom walls of the heat transfer section 50, and the temperature of the fumigant rises and it evaporates. In other words, the combustion base is vaporized, and the active ingredient diffuses through the holes in the lid 60 together with this vapor.
The amount of water put into the outer container 10 and the heating temperature of the fumigant are similar to the amount of liquid (A) put into the outer container 10 and the heating temperature of the fumigant in the fumigation method of the first embodiment.

<Other embodiments>
The smoking device used in the smoking method of the present invention is not limited to the above-mentioned device. For example, a smoking device 2 shown in FIG. 2 may be used.

The smoking device 2 shown in FIG. 2 is the same as the smoking device 1 shown in FIG. 1, except that an annular wall 23 is provided extending downward from the periphery of the bottom 24 of the inner container 20, and the bottom 24 of the inner container 20 is made of a water-permeable material 241c. Therefore, in FIG. 2, the same components as those in FIG. 1 are given the same reference numerals, and their description will be omitted.

The inner container 20 of the smoking device 2 is configured so that the lower end 22d of the annular wall 23 contacts the bottom 14 of the outer container 10, and the bottom 24 is spaced apart from the bottom 14 of the outer container 10. A notch is formed in the annular wall 23.
The water-permeable material 241c constituting the bottom 24 of the inner container 20 may be, for example, a nonwoven fabric or mesh having holes of a size that allows water to pass through but does not allow the heat generating agent constituting the heating section 30 to pass through. This allows water to enter the inner container 20 from the bottom 24 during use, causing the heat generating agent to generate heat. Examples of the nonwoven fabric include the nonwoven fabric exemplified above in the description of the smoking device 1 shown in FIG. 1.

In addition, the smoking device 1 shown in Fig. 1 and the smoking device 2 shown in Fig. 2 have a cylindrical shape for the heated part 40, but it may also be mortar-shaped. Furthermore, the outer container 10 and the inner container 20 in Figs. 1 and 2 are cylindrical, but the shape of the tube is not limited, and may be cylindrical or rectangular.

<Action and effect>
In the above-described fumigation method, liquid (A) containing water and component (B) and having a viscosity of 3.5 to 30 mPa·s at 25°C is brought into contact with calcium oxide, and the fumigant is heated by the heat of reaction between water and calcium oxide, so that the start of fumigation can be delayed compared to the case where only water is brought into contact with calcium oxide. For example, in the first or second embodiment, the time from placing the inner container 20 on the protrusion 15 of the outer container 10 containing the liquid (A) until the start of smoke generation can be extended. By delaying the start of fumigation, when fumigating a narrow space such as under the floor of a building where it is difficult for workers to evacuate, or a large space such as a large warehouse where a large amount of fumigant is used at once, smoke generation can be prevented from starting while the workers are evacuating or working, and the safety of the workers can be ensured. In addition, the effect of improving the volatilization rate of the fumigant and the effect of suppressing clogging of the lid body 60 during fumigation can be obtained.
In particular, if the viscosity of liquid (A) at 25°C is 5.5 mPa·s or more, the effect of delaying the start of smoking, the effect of improving the volatilization rate, and the effect of suppressing clogging of the lid are more excellent, and further, the burnt odor during smoking can be suppressed.
It is believed that delaying the start of fumigation results in a gentler evaporation state of the fumigation agent, an improved evaporation rate, less clogging of the lid body 60, less burning of the fumigation residue, and an improved odor.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following description.

<Materials used>
(Fumigants)
Silver-based agent: silver-supported zeolite-based inorganic antibacterial agent (manufactured by Sinanen Zeomic Corporation, product name "Zeomic AJ10N", silver content 2.5 mass%, average particle size approximately 2.5 μm).
IPMP: 3-methyl-4-isopropylphenol (manufactured by Osaka Kasei Co., Ltd.).
Azodicarbonamide: product name "Vinihol AC#3-K7" manufactured by Eiwa Chemical Industry Co., Ltd.
Zinc oxide: manufactured by Sakai Chemical Industry Co., Ltd., product name "Japanese Pharmacopoeia Zinc Oxide".
Hydroxypropyl methylcellulose: product name "Metolose 60SH-50", manufactured by Shin-Etsu Chemical Co., Ltd.
POE-POP block polymer: trade name "Pluronic RPE1740" manufactured by BASF Japan Ltd., a triblock surfactant represented by the above formula (1).
Fragrance: a fragrance composition described in Table 1 of JP 2013-249262 A.
Clay: Product name "NK-300C" manufactured by Showa Mining Co., Ltd.

(Component (B))
B1-1: Xanthan gum (manufactured by Kelco, trade name "Kelzan T").
B1-2: Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name "Poval PVA-624").
B1-3: Cellulose nanofiber (manufactured by Mori Machinery Corporation, product name "C-100").
B1-4: Carboxyvinyl polymer (manufactured by BF Goodrich, trade name "Carbopol 934").
B2-1: POE(7) alkyl (branched C13) ether (manufactured by Lion Chemical Co., Ltd., product name "RHA-234 TAG-90").
B2-2: POE(8) alkyl (branched C10) ether (manufactured by BASF Japan, trade name "Lutensol XP89").
B2-3: n-dodecylmethylamine oxide (manufactured by Lion Specialty Chemicals Co., Ltd., trade name "AX-CS").
B'2-1: Potassium coconut oil fatty acid (manufactured by Lion Chemical Co., Ltd., trade name "Potassium coconut oil fatty acid").
B'2-2: Benzalkonium chloride solution (manufactured by Lion Akzo, trade name "Arcade CB-50").
The number in parentheses after POE indicates the average number of repeating oxyalkylene groups.

(water)
Water: Tap water (Lion Corporation Hirai Research Institute).
(Calcium oxide)
Calcium oxide: Yoshizawa Lime Industry Co., Ltd., product name "CAg", rotary kiln fired product (produced by Kudzu), bulk density 0.80 g/cm ³ (20° C.)).

<Production of fumigants>
According to the following procedure, a fumigant having the composition shown in Table 1 was produced. The unit of the blend amount of each material in Table 1 is mass %. "Balance" is the amount in which the total amount of the fumigant is 100 mass %.
At room temperature (20°C), the materials were mixed in a kneader (Moriyama Corporation, "S5-2G type") according to the composition shown in Table 1, and then 10 parts by mass of water was added to make a mixture, with the total amount of the composition being 100 parts by mass. The mixture was granulated using a pre-extrusion granulator (Fuji Paudal Corporation, "EXK-1") with a die having an opening of 2 mm in diameter to obtain a granulated product. The granulated product was cut into pieces of 2 to 5 mm in length using a flash mill (Fuji Paudal Corporation, "FL300") and dried for 2 hours in a dryer (Alp Corporation, "RT-120HL") set at 70°C to obtain a granular fumigant.

<Preparation of Liquid (A)>
According to the following procedure, liquids (A) (S1 to S16, R1 to R5) were prepared with the compositions shown in Tables 2 and 3. The unit of the amount of each material in Tables 2 and 3 is g. The "balance" is the amount that makes the total amount of liquid (A) 100 g.
At room temperature (20° C.), water was placed in a 200 mL glass beaker according to the composition shown in Tables 2 and 3, and component (B) was added thereto and stirred at 500 rpm until the liquid became transparent and uniform.
The viscosity (mPa·sec) of the resulting liquid (A) at 25° C. was measured by the following measurement method. The results are shown in Table 2.

(Method of measuring viscosity)
Liquid (A) was placed in a 100 mL glass container (manufactured by Tokyo Glass Instruments Co., Ltd., product name "SV-100", outer diameter 40 mm × height 120 mm, inner mouth diameter 26.5 mm, PS bottle), and the viscosity of Liquid (A) was measured after rotation at 60 rpm for 60 seconds using a B-type viscometer (TOKI SANGYO CO., LTD., BLII type viscometer, No. 1 rotor).

[Examples 1 to 20, Comparative Examples 1 to 8]
<Measurement of smoking start time>
The smoking start time was measured by the following method 1 or 2, and the delay effect was evaluated based on the measurement results according to the following evaluation criteria. Tables 4 and 5 show the methods used, the smoking start time, and the evaluation results.

(Method 1: A method of supplying a previously prepared liquid (A) to a smoking device)
An inner container 20 having the configuration shown in Fig. 1 was prepared. The inner container 20 was filled with calcium oxide in an amount shown in Tables 4-5, the heat transfer section 50 of the inner container 20 was filled with the smoking agent in an amount shown in Tables 4-5, and a lid 60 was attached. Separately, 20 g of liquid (A) shown in Tables 4-5 was placed in a plastic container for smoking. The inner container 20 filled with the smoking agent and calcium oxide was placed on top of the plastic container containing the liquid (A). The time from placing the inner container 20 until smoke began to be emitted was measured with a stopwatch, and this time was taken as the smoking start time. In this case, if no smoke was emitted after 10 minutes, it was determined that there was a smoke failure.

(Method 2: A method in which component (B) is attached in advance to the part of the smoking device that is used to heat the smoking agent and that comes into contact with water.)
An inner container 20 having the configuration shown in FIG. 1 was prepared. The inner container 20 was filled with calcium oxide in an amount shown in Tables 4-5, the heat transfer portion 50 of the inner container 20 was filled with the smoking agent in an amount shown in Tables 4-5, and the lid 60 was attached. Separately, 20 g of the liquid (A) shown in Tables 4-5 was placed in a plastic container for smoking, and the plastic container was heated at 110°C for 6 hours to evaporate the liquid (A), and cooled to room temperature. Then, 20 g of water was placed in the plastic container. The inner container 20 filled with the smoking agent and calcium oxide was placed on top of the plastic container containing water. The time from the placement of the inner container 20 until smoke began to be emitted was measured with a stopwatch, and this time was taken as the smoking start time. In this case, if no smoke was emitted after 10 minutes, it was determined that the smoke generation was poor.

(Evaluation criteria for delay effect)
XXX: Smoking start time is more than 300 seconds.
〇〇〇: Smoking start time is more than 120 seconds but less than 300 seconds.
〇〇: Smoking start time is more than 60 seconds but less than 120 seconds.
○: Smoking start time is between 40 and 60 seconds.
△: Smoking start time is 35 seconds or more but less than 40 seconds.
×: Smoking start time is less than 35 seconds.

<Evaluation of clogging of the lid>
In the above <Measurement of smoking start time>, the clogging state of the lid body 60 was visually observed one hour after placing the inner container 20 on the plastic container, and evaluated according to the following evaluation criteria. The results are shown in Tables 4 and 5. For the cases with poor smoking, clogging was not evaluated.
(Evaluation criteria for clogging of the lid)
〇〇: No clogging.
◯: Slight clogging observed.
Δ: Clogging was observed in about 1/3 of the lid.
×: Clogging was observed in 1/2 or more of the lid.

<Measurement of volatilization rate>
In the above <Measurement of fumigation start time>, 12 hours or more after placing the inner container 20 on the plastic container, the lid 60 was opened, the fumigating agent residue was removed, and its mass (g) was measured. The volatilization rate was calculated from the mass of the loaded fumigating agent (=4g) using the following formula, and evaluated according to the following evaluation criteria. The results are shown in Tables 4 and 5. For cases where smoke generation was poor, the volatilization rate was set to 0%.
Volatilization rate (%) = 100 - [mass of fumigant residue (g) / mass of filled fumigant (g)] x 100
(Evaluation criteria for volatilization rate)
〇〇〇: Evaporation rate is over 65%.
〇〇: Evaporation rate is between 60% and 65%.
○: Evaporation rate is 58% or more but less than 60%.
△: The evaporation rate is 55% or more and less than 58%.
×: Evaporation rate is less than 55%.

<Evaluation of burnt odor>
In the above <Measurement of smoking start time>, one hour after placing the inner container 20 on the plastic container, the odor at the upper part of the inner container 20 was evaluated sensorily according to the following evaluation criteria. The results are shown in Tables 4 and 5. For the cases with poor smoking, the burning odor was not evaluated.
(Evaluation criteria for burnt odor)
〇〇: No burnt smell - only a slight smell.
○: There is a slight burnt smell.
×: A burnt smell is clearly detected.

In Examples 1 to 17, the smoking start time was longer and the smoking start was delayed compared to Comparative Example 1, in which water was used as the liquid (A). In addition, the volatilization rate was improved and clogging of the lid was suppressed. In particular, in Examples 2 to 9 and 11 to 17, the burning odor was also suppressed.
In Examples 18 to 20, in which the amount of liquid (A) or calcium oxide was changed, the smoking start time was longer and the smoking start was delayed compared to Comparative Examples 6 to 8, in which water was used as liquid (A). In addition, the volatilization rate was improved and clogging of the lid was suppressed. The burnt odor was also suppressed.

On the other hand, in Comparative Example 2 in which the viscosity of the liquid (A) exceeded 30 mPa·s, smoke generation was poor.
In Comparative Example 3, in which the viscosity of the liquid (A) was less than 3.5 mPa·s, the effect of delaying the start of smoking was small. In addition, the effect of improving the volatilization rate and the effect of suppressing clogging of the lid were not observed.
In Comparative Example 4, in which the viscosity of the liquid (A) was less than 3.5 mPa·s and the anionic surfactant B'2-1 was used as the component (B), poor smoke generation was observed.
In Comparative Example 5, in which the viscosity of the liquid (A) was less than 3.5 mPa·s and the cationic surfactant B2'-2 was used as the component (B), poor smoke generation was observed.

1...smoking device, 2...smoking device, 10...outer container, 12...peripheral wall, 12a...inner surface, 14...bottom, 14a...inner bottom surface, 15...projection, 20...inner container, 20e...upper end surface, 22...side wall, 22a...inner surface, 22b...outer surface, 22c...upper end, 22d...lower end, 23...annular wall, 24...bottom, 241...permeable bottom plate, 241a...water passage hole, 241b...plate, 241c...permeable material, 26...connecting member, 26a...ventilation hole, 30...heating part, 40...heated part, 50...heat transfer part, 50b...outer surface, 50c...upper end, 50e...upper end surface, 51...center of inner bottom surface, 54...bottom, 60...lid

Claims (6)

A fumigation method of an indirect heating system, comprising contacting a liquid (A) containing water with calcium oxide and heating a fumigant by the reaction heat between the water and the calcium oxide,
The liquid (A) contains one or more smoke initiation retardants (B) selected from the group consisting of polymer compounds (B1) and nonionic surfactants (B2);
A fumigation method, wherein the viscosity of the liquid (A) at 25°C is 3.5 to 30 mPa·s. The fumigation method according to claim 1, wherein the polymer compound (B1) is one or more selected from the group consisting of xanthan gum and polyvinyl alcohol. The fumigation method according to claim 1 or 2, wherein the nonionic surfactant (B2) is one or more selected from the group consisting of polyoxyethylene alkyl ether type nonionic surfactants and alkylamine oxide type nonionic surfactants. The fumigation method according to any one of claims 1 to 3, wherein the nonionic surfactant (B2) is a polyoxyethylene alkyl ether type nonionic surfactant having a branched alkyl group. A smoking device of an indirect heating type, comprising: a cylindrical outer container with a bottom; and a cylindrical inner container with a bottom having a water permeable bottom, which is provided within the outer container; a heating section filled with calcium oxide and a heated section filled with a smoking agent are provided within the inner container via a heat transfer section; water is stored in the outer container, and the smoking agent is heated by the heat of reaction between the water and the calcium oxide;
One or more fumigation initiation retardants (B) selected from the group consisting of polymer compounds (B1) and nonionic surfactants (B2) are attached to the portion of the outer container in which water is stored,
A smoking device in which the amount of the fumigation initiation retardant (B) attached to the portion of the outer container is an amount such that the viscosity of a liquid obtained by mixing the water stored in the outer container and the fumigation initiation retardant (B) at 25°C is 3.5 to 30 mPa·s. A smoking device of an indirect heating type, in which a heating section filled with calcium oxide and a heated section filled with a smoking agent are provided via a heat transfer section, the calcium oxide reacts with water, and the smoking agent is heated by the reaction heat;
A liquid (A) containing water and one or more smoke initiation retardants (B) selected from the group consisting of a polymer compound (B1) and a nonionic surfactant (B2), and having a viscosity of 3.5 to 30 mPa·s at 25°C ;
A smoke device unit comprising:

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