JPH0822809B2 - Ant repellent and wood insect repellent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to 0,0-diethyl 0-3,5,6-trichloro-2-
The present invention relates to a termite repellent and a wood insect repellent containing a mixture of pyridyl phosphorothioate and 0,0-diethyl 0-dichlorophenyl phosphorothioate as an active ingredient.

[Prior Art] In recent years, there has been a remarkable growth in demand for timber materials including construction materials in Japan.

For this reason, domestic timber resources alone cannot meet the demand. Therefore, not only coniferous timber but also overseas timber and African timber that have not been used so far are imported and used in various fields.

The use of such timber, particularly for construction timber, is desired to be durable, but due to its nature, timber is prone to decay, and also serves as a nutritional source for termites, flat beetles, or bugs. Therefore, it is easily damaged by termites, flat beetles, and the like.

In particular, the damage of wood by termites and the like is great, and various types of ant and insect repellents have been developed and used conventionally.

For example, representative ones include organic chlorine insect repellents such as chlordane, dieldrin, γ-BHC, DDT, and chlornaphthalene, 0,0-diethyl 0- (3-methyl-4-nitrophenyl) thiophosphate, Organic phosphorus compounds such as phenylglyoxylonitrile oxime 0,0-diethyl phosphorothioate and 0,0-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate are known.

[Problems to be Solved by the Invention] However, organochlorine insect repellents such as chlordane, dieldrin, and DDT have high residual toxicity and are persistent compounds, which cause environmental pollution problems. Instead, organophosphorus termites have been reviewed and developed.

For example, 0,0-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate (hereinafter referred to as "chlorpyrifos") is used as a typical organophosphorus termite control agent. That problem has been pointed out.

In general, an anti-termite agent is used as a drug solution dissolved in a desired solvent even if it is chlorpyrifos for reasons of use, transportation and storage.

However, chlorpyrifos has a melting point of 42.0-43.5 ° C.
Since it is a white granular crystal at room temperature, even if it is used as a liquid agent dissolved in an appropriate solvent, the crystal will precipitate and the drug composition will become heterogeneous depending on the storage conditions, not to mention the winter season. There is a phenomenon in which the fluidity is impaired and the inner wall of the container is solidified, which is extremely inconvenient for taking out from the container and for use.

In particular, chlorpyrifos also has a bad odor by its nature, and when a volatile solvent is used, this odor is further promoted, and not only problems in use operation but also drawbacks such as a bad odor remaining after soil treatment. is there.

Further, conventional organophosphorus termites such as chlorpyrifos can be used as wood insect repellents as described above, but generally have poor stability, and even if they are approved by the JAS standard, they are not thermally stable. In addition, it easily decomposes on the alkaline side, and lacks the so-called physicochemical stability of the chemicals, so that there is a problem that the period of keeping the termite / insect repellent performance on wood is short due to aging.

For example, in the case of preparing a plywood by blending a predetermined amount of the above-mentioned chemicals with a phenol-based adhesive, the bonding operation is performed under a hot pressure condition of 120 to 140 ° C, but at such a temperature, the adhesive composition Degradation of the drug is caused by pH, and it often happens that the quality standard of 0.1 kg / m ³ of drug in plywood cannot be guaranteed.

Therefore, it can be solved by increasing the amount of the drug to be set in advance, but this is not economical and is not preferable because it causes problems such as drug damage.

In view of the problems inherent to chlorpyrifos as described above, the inventors of the present invention have made earnest studies to improve an anti-termite agent for chlorpyrifos, and found that it is a mixture with 0,0-diethyl 0-dichlorophenylphosphorothioate. However, surprisingly, they found that the above problems could be solved all at once, and completed the present invention.

[Means for Solving the Problems] That is, the present invention provides a mixture of 0,0-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate (chlorpyrifos) and 0,0-diethyl 0-dichlorophenyl phosphorothioate. It is an anti-termite agent that is the active ingredient.

Further, the present invention is directed to 0,0-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate (chloropyrifos)
And a wood insect repellent containing a mixture of 0,0-diethyl 0-dichlorophenyl phosphorothioate as an active ingredient.

[Operation] In the present invention, 0,0-diethyl 0-dichlorophenyl phosphorothioate (also referred to as 0,0-diethyl 0-dichlorophenyl thiophosphate) (hereinafter referred to as “ECP”) used as a mixture of chlorpyrifos is a pesticide. Known as an insecticide for use, for example, a drug used as an insecticide for vegetables such as onions, beans, cucumbers, etc., the present inventors have a different drug from the target pests of the insecticide for agricultural chemicals. We have found that it is unexpectedly effective against insects such as termites and flat beetles that use wood as a nutrient source, and surprisingly it is extremely stable even in heat and at high pH. It was confirmed by a number of tests that it has excellent suitability not only as an agent but also as a wood insect repellent.

In the present invention, the insect repellent of wood is as described above.
It means that it has a bactericidal action against insects such as termites, flat beetles, and water worms that use wood as a nutrient source.

Further, wood is not particularly limited as long as it is mainly made of wood, but can include various types of construction wood, particle boards, plywood, etc., and plywood is the most targeted from a practical viewpoint. It will be.

In the termite repellent and wood insect repellent according to the present invention, the ECP mixed with chlorpyrifos is particularly 0,0-diethyl 0-2,4-
Dichlorophenyl phosphorothioate (hereinafter "2,4-EC
P)) is industrially preferable.

ECP, especially 2,4-ECP, has a melting point of 10-13 ° C and is a colorless to pale yellowish-brown liquid at room temperature, and although it has a slight thiophosphate ester odor, it hardly smells as compared with chlorpyrifos. .

On the other hand, the odor of chlorpyrifos has a characteristic malodor because it has a halogenated pyridine skeleton structure by its nature, but in many cases, a small amount of impurities that are inevitably incorporated also contribute to this odor. I think that the.

However, ECP is compatible with such chlorpyrifos, and it is surprising that the mixed solution thereof remarkably reduces odor as compared with a solvent obtained by dissolving chlorpyrifos in an aromatic solvent such as xylene.

Such a favorable phenomenon is totally unexpected and is probably ECP.
Is considered to have a strong effect of suppressing the decomposition of chlorpyrifos and the vapor pressure of the malodorous component as compared with other solvents.

Therefore, the mixed solution in which crystals of chlorpyrifos are dissolved in ECP is not only stable as a liquid agent, but the most preferable feature of the present invention is that the mixed solution is present in the presence or absence of other solvent. That is, substantially no crystallization of chlorpyrifos occurs.

These are none other than the convenience in handling of chlorpyrifos during its formulation, but also many advantages in the use of the formulation.

As described above, ECP is an effective solvent for chlorpyrifos in the preparation and, as described above, ECP itself has excellent anti-termite and wood-repellent action. The concentration of the drug substance active ingredient can be increased.

The amount of ECP to be mixed with chlorpyrifos is not particularly limited, but in many cases, a range of 10 to 50% by weight of chlorpyrifos and 90 to 50% by weight of ECP per mixture is suitable.

In the present invention, it is particularly preferable that the mixture of both is a liquid under the conditions of standing at room temperature for 48 hours in the presence or absence of auxiliary additives such as other solvents.

The termite control agent and wood insect control agent according to the present invention use the above mixture as an active ingredient, but do not exclude the combined use with other termite control agents.

For example, 0, which is known as a typical organophosphorus termite
0-dimethyl 0- (3-methyl-4-nitrophenyl)
Thiophosphate, phenylglyoxylonitrile oxime 0,0-diethyl phosphorothioate (foxime),
0,0-diethyl 0- (3-oxo-2-phenyl-2H-
1,1,1,2,6,7,7,7 known as pyridazin-6-yl) phosphorothioate (offnack) and synergists thereof
-Octachloro-4-oxaheptane (S-421) and the like can be used as necessary.

In the termite control agent and wood insect control agent according to the present invention, since ECP acts as a solvent for chlorpyrifos,
These mixtures themselves can be used as a formulation.

However, in many cases, for the purpose of facilitating penetration into soil or wood, or for adjusting the concentration of drug substance, or for other reasons, the mixture is treated with a surfactant or other solvent based on well-known formulation means. It is preferable to formulate a drug as an emulsion or a liquid formulation by mixing an auxiliary additive.

Examples of auxiliary additives for such formulation include sulfonate type such as alkylbenzene sulfonate, carboxylate type such as alkyl ether carboxylic acid, sulfuric acid ester type such as alkyl allyl ether sulfate, and alkyl ether phosphate. Salt-based anionic surfactants; ether-based nonionic surfactants such as alkyl and allyl polyoxyethylene ethers; ether ester-based surfactants such as polyoxyethylene ethers of glycerin esters; ester-based nonionic surfactants such as polyethylene glycol fatty acid esters; water, kerosene , Light oil, paraffin solvent, solvent naphtha, benzene, xylene, toluene, high boiling aromatic solvent, methyl ethyl ketone, methyl butyl ketone, cellosolve solvent, cyclohexane, cyclohexanol, cyclohexanone, Glycol, ethyl butyl alcohol, butyl ether, amyl acetate, solvents such as benzyl acetate and the like; sticking agents, antioxidants, coloring agents, can be used as needed antirust or flame retardants.

Since the termite repellant according to the present invention is also suitable as a wood insect repellent as described above, it can be used by treating the target wood with a chemical treatment such as dipping, brushing, spraying, press fitting, etc., but in many cases It is particularly preferable to use it by blending it with an adhesive for plywood.

That is, the wood insect repellent according to the present invention can be prepared by a conventional method by blending a predetermined amount of the synthetic resin as a main composition into an adhesive composition.

Typically, phenolic resins (including modified resins),
Melamine-based resins, urea-based resins, urea, thermosetting resins that can be condensed with so-called formaldehyde such as melamine-based resins are suitable as general-purpose adhesives, but are not limited to these, other synthetic resins, For example, vinyl acetate resin, acrylic resin, epoxy resin or the like may be used.

In addition, flour as another compounding agent that can constitute the adhesive,
It does not matter at all to mix other starches, a sizing agent such as CMC, and constituents that are used normally or as needed.

If desired, a surfactant or solvent as described above or a curing agent such as ammonium chloride, ammonium phosphate, or ammonium acetate, and further other agents such as borax,
Boric acid, a chromium compound, another organic phosphorus compound, an organic tin compound, a water repellent, a flame retardant, a colorant and the like can be appropriately used in combination.

The content of the agent according to the present invention in the adhesive is not uniform depending on the purpose of use, method of use, composition of the adhesive, etc., but is generally in the range of 0.05 to 5% by weight, and in most cases, in the target wood. For the purpose of evaluation by the content of the active ingredient of, for example in plywood 0.
It can be compounded by setting it to a predetermined amount so as to be in the range of ^{3 to} 0.5 kg / m ³ (plywood).

It is not necessary to use a special method for producing insect-repellent wood by using the adhesive for insect-repellent wood, and it is possible to easily obtain insect-repellent wood, especially plywood with insect-repellent wood by the conventional method of mixing synthetic resin adhesives. .

That is, while the core veneer is fed through a roll spreader, a deposition step of adhering the prepared insecticidal paste solution to the core veneer, a temperature of 120 to 140 ° C., and 8 to 12 kg / cm ² depending on the material type.
In p., The insect-repellent plywood can be obtained through a hot-pressing step of setting a predetermined time according to the thickness of the plywood and applying heat.

Generally, chlorpyrifos and other organic phosphorus insect repellents are easily decomposed in alkaline adhesives or in the production of plywood requiring the above-mentioned hot pressing process, and so-called physicochemical stability of the drug is lacking. Although it is necessary to increase the compounding amount in advance and set it, ECP has excellent physicochemical stability.
The wood insect repellent according to the present invention can be effectively mixed with an adhesive as an insect repellent for plywood.

[Examples] The present invention will be further described with reference to Examples.

Example 1 Various antitermites (liquid agents) containing chlorpyrifos (hereinafter referred to as “CP” in Examples) and 2,4-ECP as active ingredients were prepared, and their low-temperature stability and odor were evaluated. Upon evaluation, the results shown in Table 1 were obtained.

 The evaluation method was performed under the following conditions.

Normal temperature stability: Immediately after placing 50 ml of a sample in a 100 ml test tube and after leaving it in the dark for 48 hours, the presence or absence of crystallization is observed and evaluated by a three-stage method. ◎… not crystallized, ○… slightly crystallized, ×… crystallized; Odor: 3 ml sample was taken and placed in a test tube and sealed, left at room temperature for 1 hour, then opened and opened from above The degree of odor is evaluated by a sensory test in a 4-step method. ∘: Almost no odor, ○: Slight odor, Δ: Smell, ×: Strong odor.

Example 2 (Test Example) Several representative ant-repellent agent samples prepared in Example 1 were subjected to an anticidal test using the paper contact method in order to see the anticidal effect on the termites.

Prepared sample and chlordane oil for comparison
Dilute to the concentration shown in the table, soak the resulting diluted solution in paper, air dry, spread on a Petri dish, and place termites on it.
When 20 dogs were put in each and they were bred in an incubator and the number of deaths was counted, the results shown in Table 2 were obtained. The blank in Table 2 represents untreated paper.

Example 3 In order to investigate the termite control efficacy of soil treatment using the termite control agent according to the present invention, an indoor termite control test was conducted under the following conditions.

Indoor test container: Performed using the indoor test container shown in FIG. That is, this test container has an inner diameter of 50 mm and a height of about 12
Approximately 2 pieces of 0 mm glass cylinders B and C from the bottom of each
A glass tube A having an inner diameter of about 20 mm and a length of 105 mm at 0 mm (the length D of the transparent portion excluding the rubbing portions at both ends is 50 mm and is graduated every 5 mm) is used for communication.

Test method: Using the container shown in Fig. 1, part E was filled with untreated soil (dry heat sterilized Sunday loam with a particle size of 20 mesh or less), part D was treated with the chemical, and part G was filled with sawdust. After that, 300 of the termite ants and 30 soldier ants are randomly placed in the F section.

Then, this test container is allowed to stand in a thermostatic chamber at a temperature of 28 ± 2 ° C. for observation.

The chemical-treated soil was mixed with 10 parts by weight of untreated soil and 1 part by weight of the chemical and mixed thoroughly, and allowed to stand for 30 days in the mixed soil (without weathering operation) and a thermostat of 40 ± 2 ° C. The soil subjected to weathering was used as the test soil.

Evaluation method: The progress of the termites in the test soil was observed for each test container, and the number of days (A) of the termites (the number of days required for all the ants to die) and the perforation distance to the test soil were observed. Is expressed by the degree of perforation on a 5-point scale.
The results obtained are shown in Table 3.

Example 4 Preparation of insect-repellent plywood: Plywood adhesive consisting of 100 parts by weight of thermosetting resin for plywood, 30 parts by weight of flour, 1 part by weight of curing agent, 20 parts by weight of water and set amount of insecticide (about 0.5 parts by weight) A paste solution was prepared and plywood was prepared by a conventional method.

That is, Lauan core veneer (3 mm), front veneer (1 mm),
A back single plate (1 mm) was used. The coating operation was set so that the insect repellent was applied to both sides of the core veneer at a rate of 0.4 kg / m ^{3 in} the plywood, and then 10 kg / cm ^{2 was} subjected to a cold pressure process for 1 hour to obtain plywood. Then, a plywood was produced by a hot pressing process under the conditions of 120 ° C. for 3 minutes.

Under the above-mentioned plywood production conditions, various thermosetting resins (4 types) were used, and mixture agents A, B, C and
A total of 16 types of plywood were prepared using different resins and insect repellents by using a commercially available organic phosphorus-based termite control agent (S) approved by JAS for comparison.

Stability test of insect repellent: 16 kinds of insect repellent plywood obtained above was held at 60 ℃ for 18 hours to cut a 30 cm × 30 cm square plate test piece,
Then, this was cut in a diagonal line, the wood powder scraped from this cut surface was used as a sample to determine the content of the insect repellent in the sample, and the recovery rate was calculated from this value and the set amount, respectively. When the stability of the insect repellent was evaluated, the results shown in Table 4 were obtained.

As can be seen from the above results, it was revealed that the insect repellent according to the present invention is extremely stable as compared with commercially available organophosphorus insect repellents against changes in physicochemical conditions such as heat and pH. .

Example 5 A test piece of a Quercus oak veneer (thickness 1 mm) was immersed in an oil emulsion of a mixture of 2,4-ECP and CP, and then it was examined whether or not the emergence of larvae of the flat beetle was prevented. According to the Japan Wood Preservation Association Standard No. 8 and the insect repellent efficacy test method (1) for wood repellents, the repellent efficacy against larvae of the flatworm Beetle was tested. The results are listed in Table 5 below.

[Effects of the Invention] The termite control agent according to the present invention has not only the characteristic solvent of chlorpyrifos but also ECP itself, and thus has the same or more termiticide effect as chlorpyrifos.

Moreover, conventionally, the drug-caking property associated with malodor and crystallization, which has been a drawback of chlorpyrifos, can be substantially avoided by the termiticide according to the present invention.
The handling can be very advantageous.

Furthermore, since the termite control agent according to the present invention has physicochemical stability under heat and pH conditions, it can be effectively used as a wood insect control agent.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an indoor test container for investigating the termite-preventing effect of treated soil treated with a termite-preventing agent. In the figure: A, B, C ... Glass cylinders, B and C are symmetrically connected to A at the bottom; D ... Drug-treated soil filling section; E ... Untreated soil; G ... Sawdust; F ... Test ant input section.

Claims (5)

[Claims] 1. 0,0-Diethyl 0-3,5,6-trichloro-2
-Pyridyl phosphorothioate and 0,0-diethyl 0-
An anti-termite agent containing a mixture of dichlorophenyl phosphorothioates as an active ingredient. 2. The mixture comprises 10-50% by weight of 0,0-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate.
And 0,0-diethyl 0-dichlorophenyl phosphorothioate in the range of 90 to 50% by weight. 3. The termite control agent according to claim 1 or 2, wherein the mixture is a liquid in the presence or absence of an auxiliary additive at room temperature for 48 hours. 4. A 0,0-diethyl 0-dichlorophenyl phosphorothioate is 0,0-diethyl 0- (2,4-dichlorophenyl) phosphorothioate.
The termiticide according to any one of items 1 to 3. 5. 0,0-diethyl 0-3,5,6-trichloro-2
-Pyridyl phosphorothioate and 0,0-diethyl 0-
A wood insect repellent containing a mixture of dichlorophenyl phosphorothioates as an active ingredient.