JPH0925202A - Solvent for pest-controlling agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a solvent high in solubility for the base substance of a pest-controlling agent, good in penetrability into woods and in emulsion stability, and suitable for agents for controlling pests, especially termites, by using a specific diphenyl derivative. SOLUTION: An alkyldiphenylmethane of the formula (R is a 1-4C alkyl) is used as this solvent. Bezyltoluene is suitable as the alkyldiphenylmethane of the formula. An isomer mixture comprising 20-80wt.% of p-benzyltoluene, 20-80wt.% of m-benzyltoluene and 0-30wt.% of o-benzyltoluene is especially preferable. Since the solvent is high in the boiling point and little in the smell, it has high safety against fires on spraying or spreading, and harmful influence due to smells and irritations are little. The solvent does not pollute environments. When a base substance for the control agent is dissolved in the solvent, the base substance is not decomposed or changed, and the deterioration of the control activity with time is not caused. The coloration phenomenon of the base substance on dissolution is little.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a solvent for use as a pest control agent for pests, especially termites.

[0002]

2. Description of the Related Art Conventionally, control agents for sanitary pests such as mosquitoes and flies, particularly termites, are solid preparations such as liquid preparations, emulsions, sol preparations, wettable powders, water solutions, oil preparations and granules depending on the application site. Depending on the formulation form such as,
It is used by being sprayed or sprayed on concrete or soil. For example, the emulsion is obtained by dissolving a control agent drug substance in an organic solvent and emulsifying this in water. The oil agent is
It is composed of a solution of the original control agent dissolved in an organic solvent. In addition, the solid formulation is prepared by dissolving the control agent drug substance in an organic solvent,
It is produced by a method of coating a carrier with the solution, impregnating the solution with the solution or kneading the solution,
Specific formulations include powders and granules. By the way, an emulsion can be diluted with water, so it is as convenient as a wettable powder, but since it is easy to prepare a chemical solution, it is more preferable because it can be easily handled, and generally has a higher control effect than a wettable powder. Tend.

Conventionally, the solvent is methyl alcohol,
Alcohols such as ethyl alcohol, ketones such as acetone and methyl ethyl ketone, ethers such as ethyl ether and cellosolve, kerosene, isoparaffin,
Aliphatic hydrocarbons such as normal paraffin, alicyclic hydrocarbons such as cyclohexane and aromatic hydrocarbons such as benzene, toluene, xylene and dodecylbenzene are used. In addition to these, phenylxylylethane (JP-A-4-13602) and the like have been proposed.

The conditions that the solvent for termite controlling agent should have are as follows. (1) It must have sufficient solubility to dissolve the required amount of the original control agent. If the solubility is high, the amount of solvent used can be reduced, which is extremely preferable. (2) When the drug substance of the control agent is dissolved, the drug substance should not be decomposed or altered so that the control effect does not decrease over time.
Particularly when used as a solid preparation, long-term sustainability of the controlling effect is important, and stability of solvent physical properties is also required. Further, it is preferable that there is little phenomenon such as coloring during dissolution. (3) When used as a solvent for emulsions, it should not damage the emulsion stabilizer. If the emulsion stability is poor, the emulsion is broken and the drug substance is precipitated. This is not preferable because it may lead to insufficient effects and drug damage. In general, a solvent having a high polarity and a high dissolving power lowers the emulsion stability, so caution is required. (4) High flash point and boiling point. Especially, since it is sprayed or sprayed under the floor of a house, it is important in terms of safety against fire. (5) A solvent that has no unpleasant odor and is preferably odorless. (6) It is inexpensive because it is used in large quantities. (7) In addition, the odor and irritation during spraying or spraying are less harmful and harmless to humans and animals.

[0005]

However, the selection criteria of the solvent are different between the field of termite control agent under the jurisdiction of the Ministry of Health and Welfare and the field of pesticide control agent under the Ministry of Agriculture, Forestry and Fisheries. Further, when a conventional solvent, for example, phenylxylylethane described in JP-A-4-13602 is used, the dissolving power for the control agent and the penetrating power for the wood material are not necessarily satisfactory. Unlike the pests in the field of agrochemicals, termites penetrate into the interior of wood, so it is necessary to penetrate the pesticide into the interior of wood, and a solvent having a small molecular weight and a low viscosity is required to further enhance the penetrating power. Among the conventionally used solvents, methyl alcohol, which has a small molecular weight,
Alcohols such as ethyl alcohol, ketones such as acetone and methyl ethyl ketone, ethers such as ethyl ether and cellosolve, kerosene, isoparaffin,
The use of aliphatic hydrocarbons such as normal paraffin, alicyclic hydrocarbons such as cyclohexane and aromatic hydrocarbons such as benzene, toluene, xylene and dodecylbenzene can be considered. However, these solvents have a low flash point, a high odor, and have problems in safety during spraying or spraying and environmental pollution. Also, some of them have a small dissolving power for the control agent. For these reasons, there is a new demand for a solvent for controlling pests, especially termites.

[0006]

The first aspect of the present invention relates to a solvent for a pest control agent, which comprises an alkyldiphenylmethane having a structure represented by the following formula [I].

Embedded image (In the formula, R represents an alkyl group having 1 to 4 carbon atoms). A second aspect of the present invention relates to a pest control agent solvent, wherein the alkyldiphenylmethane is benzyltoluene. A third aspect of the present invention is that the alkyldiphenylmethane is 20-80% by weight of p-benzyltoluene, m
-Benzyltoluene 20 to 80% by weight and o-benzyltoluene 0 to 30% by weight as an isomer mixture, which relates to a pest control agent solvent. A fourth aspect of the present invention relates to the pest control agent solvent according to the first aspect of the present invention, wherein the pest is a termite.

Hereinafter, the present invention will be further described. In general,
In a bicyclic aromatic hydrocarbon substituted with an alkyl group, the molecular weight increases as the number of carbon atoms in the alkyl group increases. Therefore, the degree of aromaticity (ratio of the number of carbon atoms in the aromatic ring to the total number of carbon atoms in the molecule) is reduced, the solubility with respect to the controlling agent is lowered, and the viscosity is also increased and the osmotic force is lowered. In order to improve the dissolving power for the control agent and the penetrating power into the wood,
In the structure shown in the above formula [I], the carbon number of the substituent R is 1
It is preferable that it is -4. Specific substituents R are methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl and the like. Therefore, specific examples of the alkyldiphenylmethane represented by the above formula [I] include benzyltoluene, ethyldiphenylmethane, isopropyldiphenylmethane, se
Examples include c-butyldiphenylmethane. These may be used alone or in combination of two or more.

More preferably, R has 1 carbon atom. A compound corresponding to this is benzyltoluene, and a control agent using this is most preferable. As shown in Table 2 below, benzyltoluene has three types of positional isomers, and the o-form has a high viscosity. Therefore, a mixture of benzyltoluene isomers whose viscosity is reduced by increasing the contents of the p-form and the m-form is preferable. Specifically, the p-form is 20 to 80% by weight, the m-form is 20 to 80% by weight, and the o-
It is preferred that the body is in the range of 0 to 30% by weight. In the formula [I], when R has 0 carbon atoms, it is diphenylmethane, but diphenylmethane has a melting point of 25 ° C.
Therefore, since it crystallizes at room temperature, it is not preferable as a solvent for the control agent.

The solvent of the present invention has a higher degree of aromaticity than that of a conventionally known solvent such as phenylxylylethane, and therefore has a high dissolving power for a control agent and has a density similar to that of water. Emulsion stability is good, and since it has a low viscosity, it has a high ability to penetrate wood materials.

Next, a method for producing the alkyldiphenylmethane represented by the above formula [I] will be described with reference to an example of benzyltoluene. Benzyltoluene can be easily produced by a conventionally known method. For example, a method of alkylating diphenylmethane with an alkylating agent such as methyl alcohol in the presence of an acidic catalyst, a method of benzylating toluene with an aralkylating agent such as benzyl chloride or benzyl alcohol, and toluene using a catalyst such as zeolite. There is a method of using a transaralkylation reaction with diphenylmethane, and a method of coupling toluene and benzene with dichloromethane.

The solvent of the present invention is a conventionally known solvent such as alcohols such as methyl alcohol and ethyl alcohol, ketones such as acetone and methyl ethyl ketone, ethers such as ethyl ether and cellosolve, kerosene, isoparaffin and normal paraffin. Higher boiling point and less odor than aliphatic hydrocarbons, alicyclic hydrocarbons such as cyclohexane and aromatic hydrocarbons such as benzene, toluene, xylene and dodecylbenzene, so it is safe against fire when spraying or spraying It is high in quality and has little adverse effect due to odor or irritation and no environmental pollution. Furthermore, when the pesticidal drug substance is dissolved, the pesticidal substance is not decomposed or altered so that the pesticidal effect is not deteriorated over time. In addition, it is a solvent for pest control agents that causes little coloring or the like when dissolved.

Since the solvent of the present invention has a high dissolving power, conventionally known solvents such as alcohol solvents such as methyl alcohol and ethyl alcohol, ketone solvents such as acetone and methyl ethyl ketone, ether solvents such as ethyl ether and cellosolve, Hydrocarbon solvents such as paraffin and naphthene, benzene, toluene, xylene, alkylbenzenes, alkylnaphthalenes such as isopropylnaphthalene, aromatic hydrocarbon solvents such as alkylbiphenyls such as isopropylbiphenyl, and alcohols having aromatic rings. A solvent such as a system, a ketone system, an ether system, or a diarylalkane system solvent other than those represented by the above formula [I], for example, phenylxylylethane, dibenzyltoluene, etc. may be mixed and used at an arbitrary ratio. it can.

The solvent for pest control agents of the present invention, especially the solvent used for termite control agents, is used as a wood termite control agent which is sprayed or sprayed or applied on the foundation of a building, wood material under the floor, concrete or the like. , But also fungi, insects, mites, nematodes, mice that harm crops, including trees and agricultural products
For the control of so-called weeds, other flora and fauna and viruses, fungicides, insecticides, herbicides, epidemics and other agents, such as rodenticides, attractants, repellents, and for enhancing or suppressing physiological functions of crops. It is also effective for the plant growth regulator used.

The pest control agent raw material used in combination with the solvent of the present invention, particularly the termite control agent raw material, is not limited to a particular one, but it has a low coloring property upon dissolution and is excellent in stability and the like. The organic phosphorus-based control agent described below is suitable. When used as an emulsion, the type of emulsifier is not specified, and any conventionally known emulsifier can be used for emulsification. Specific pest control agents to which the solvent of the present invention can be applied, particularly termite control agents include organic phosphorus-based, pyrethrin-based and carbamate-based termite control agents, and mixtures thereof. The following are specific examples of termite control agents. That is, as an organic phosphorus type, O, O-diethyl-O
-3,5,6-trichloro-2-pyridyl phosphorothioate (trade name: chlorpyrifos), tetrachlorobinphos (trade name: guardside), hoxime (trade name: barriside), etc. as a pyrethrin type, cyfluthrin,
Permethrin, Tetromethrin, Bifensulin, etc.,
As a carbamate system, 2-sec-butylphenyl-N
-Methyl carbamate (trade name: Bassa) and the like. In the above example, the name of the drug substance is the chemical name,
It is indicated by either a common name or an international standard name.

When the solvent of the present invention is specifically used, it may be in any formulation form such as solid formulations such as emulsions, oils and powders. Usually, the alkyldiphenylmethane represented by the formula [I] is used in an amount of 0.1 to 1000 parts by weight, preferably 0.5 to 500 parts by weight, per 1 part by weight of the active ingredient as the drug substance.

When used as an emulsion, the type of emulsifier is not specified, and any emulsifier known in the art can be emulsified. When used as an oil, the drug substance is simply dissolved in the solvent of the present invention, and when sprayed, sprayed or applied, it is appropriately diluted with kerosene or the like. For example, in order to form an emulsion, a solution obtained by dissolving the drug substance with the solvent of the present invention is used as a known emulsifier such as alkylnaphthalene sulfonate, dodecylbenzene sulfonate, and dialkylsulfosuccinate. And the like, or a nonionic surfactant such as polyoxyalkylene ether, polyoxyethylene sorbitan alkylate, polyoxyalkylene block polymer, etc. to be emulsified in water. In addition to the above, an antioxidant,
An ultraviolet absorber, an anti-gelling agent, etc., and in the case of an organophosphorus substance, a decomposition inhibitor, etc. can be further added.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A solvent for a pest controlling agent comprising alkyldiphenylmethane having a structure represented by the above formula [I],
It has a high dissolving power for the original biocontrol agent, good penetration into wood and good emulsion stability, and is particularly suitable for termite control agents.

[0018]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. <Example> A benzyltoluene isomer containing 35% by weight of p-form, 60% by weight of m-form, and 5% by weight of o-form by reacting diphenylmethane with toluene using a zeolite catalyst (ZSM-5). A solvent consisting of a mixture was obtained. Table 1 shows the physical properties of the solvent.

<Comparative Example> Phenylxylylethane (trade name: SA) which has been conventionally used as a solvent for termite control agents.
Table 1 shows the physical properties of S-296, manufactured by Nippon Petrochemical Co., Ltd., as a comparative example.

[0020]

[Table 1]

As shown in Table 1, the solvents of the examples have a smaller molecular weight than those of the comparative examples, and therefore have a high density, a high aromaticity and a low viscosity. The aromaticity is a parameter of the dissolving power that can be calculated from the structure, and the larger the value, the higher the dissolving power. Further, the specific dispersion was measured in order to investigate the solvent's dissolving power. The specific dispersion is used to determine the components and serves as an index indicating the solvent's dissolving power.

Table 2 shows the viscosity of each isomer of benzyltoluene. From Table 2, it can be seen that the viscosity of the o-form is high, followed by the m-form and then the p-form. Therefore, a benzyltoluene isomer mixture containing a large amount of the m-form and the p-form is preferable in order to obtain the highest permeability as a solvent for termite control agents.

[0023]

[Table 2]

Next, in order to confirm the emulsion stability, the control agent drug substance (chlorpyrifos) was dissolved using the solvents of Examples and Comparative Examples, and an emulsifier and water were added to emulsify and disperse by the following method to emulsify. Immediately and one month later, stability tests were performed. The results are shown in Table 3. The evaluation is based on the following criteria. Good: Uniform emulsion dispersion Fair: Partial phase separation Poor: Phase separation [Emulsion dispersion method] 150 parts of water and an emulsifier (trade name: GANTREZ A
N-119, manufactured by AGF Co., Ltd.) (7 parts) was added, and the mixture was emulsified with a stirrer (rotation speed: 9000 rpm).

[0025]

[Table 3]

From Table 3, it can be seen that the solvents of the Examples have the same density as that of water and the emulsion stability is good. As described above, the solvent of the example has a high molecular weight and a high aromaticity as compared with the solvent of the comparative example, and thus has a high dissolving power for the control agent, and also has a low viscosity, so that the wood material of the control agent can be used. It is a solvent for termite control agents that has good emulsification stability because it has good permeability and its density is almost the same as that of water.

[0027]

The solvent according to claims 1 and 4 of the present invention has a high dissolving power for the pesticide active substance, a high penetrating power to the base material of the building and the wood material under the floor, and when used as an emulsion. It has good emulsion stability and is suitable as a pest control agent, especially for termites. In addition, the solvent of claim 2 of the present invention is compared with a conventionally known solvent such as phenylxylylethane,
Its high aromaticity makes it highly soluble in pesticides, and its density is almost the same as that of water, resulting in good emulsion stability when used in emulsions, and its low viscosity makes it highly permeable to woody materials. . Furthermore, the invention of claim 3 of the present invention is p-
It is a mixture of benzyltoluene isomers whose viscosity is reduced by containing a large amount of isomers and m-isomers.
In particular, it is more preferable as a solvent for termite control agents.

Claims (4)

[Claims] 1. A solvent for a pest controlling agent, which comprises an alkyldiphenylmethane having a structure represented by the following formula [I]: (In the formula, R represents an alkyl group having 1 to 4 carbon atoms). 2. The solvent for pest control agent according to claim 1, wherein the alkyldiphenylmethane comprises benzyltoluene. 3. The alkyldiphenylmethane is p-
Benzyltoluene 20 to 80% by weight, m-benzyltoluene 20 to 80% by weight and o-benzyltoluene 0 to
The pest control agent according to claim 1, which is an isomer mixture consisting of 30% by weight. 4. The pest control agent solvent according to claim 1, wherein the pest is a termite.