JPS5849521B2 - The best way to go about your business - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for sustaining the effectiveness of herbicides, and more specifically, the present invention relates to a method for maintaining the efficacy of herbicides, and more specifically, the present invention relates to a method for maintaining the effectiveness of herbicides, and more specifically, by using a resin emulsion that contains a herbicide and forms a film having an appropriate moisture permeability, a resin containing a herbicide is produced. The present invention relates to a method for maintaining the effectiveness of herbicides by forming a layer such as the above on plants or on the soil surface.

In recent years, as the necessity of environmental conservation has been recognized, the damage caused by weeds has been taken up as a major social issue.

In particular, weed pollution has become a problem, such as the danger of fires caused by drying up weeds, the pollen of ragweed and goldenrod that can cause rhinitis and cough, and the breeding grounds of mosquitoes, poisonous moths, and field mice. However, due to the severe shortage of labor, the weeding work is changing from manual weeding to simple weeding using herbicides.

However, in the case of weed control using herbicides, it is necessary to spray the chemical two to four times a year for complete weed control.
It has a number of drawbacks, including the risk of contaminating the environment around the area where the herbicide has been sprayed.

In other words, when herbicides are used alone, they may be washed away by rainwater, decomposed in the soil, or, in the case of some types of herbicides, volatilized into the atmosphere within a relatively short period of time after being sprayed. It has the disadvantage that it easily loses its effectiveness.

In order to overcome this drawback, spreaders for agricultural chemicals have traditionally been used in combination with herbicides, but even with this method, it is difficult to maintain the efficacy of the herbicides to a sufficiently satisfactory level.

In addition, various other methods have been proposed in the past as methods for improving this.

For example, (1) a method of preparing a herbicide by coating or mixing and molding with a synthetic resin (JP-A-48-72338, JP-A-47
-20347, Special Publication Showa 47-27937, Special Publication Publication No. 41-
19080, etc.), (2) A method of using a herbicide mixed with an aqueous solution of a water-soluble resin (Japanese Patent Publication No. 10535, Japanese Patent Publication No. 48-1.6176, etc.) (3) A method of reacting a herbicide with a natural resin. (4) A method of mixing a herbicide with a polymer composition that reacts and solidifies in water and adding water (Japanese Patent Publication No. 48-8599, etc.).
860, Special Publication No. 46-35400, etc.).

However, although each of these methods has some effects, they are not fully satisfactory.

That is, as a disadvantage, for example, it is expensive [above ((
method 1)], the high viscosity of the product makes it difficult to spray with a sprayer [method (2)], and the types of herbicides that can be used are limited [(1), (3) methods], it is difficult to spray with a sprayer because the viscosity increases during use and it solidifies in a relatively short time, and it is inconvenient because it must be mixed immediately before use [(4)
), which are not fully satisfactory in practical terms.

As a result of repeated research to improve these drawbacks, the present inventors have found that by using a herbicide in combination with a certain kind of resin emulsion, a resin layer containing the herbicide is formed on the plant body and the soil surface layer. The present invention was completed based on the discovery that the efficacy of the herbicide can be maintained for a long period of time (at least half a year) by keeping the amount of the herbicide leached from the resin layer by rainwater at an appropriate level.

That is, the present invention provides for the use of herbicides alone or in combination with two or more herbicides.
0 0 ~ 1 8 0 0? /m/ 2 4 hr
This is a method for maintaining the efficacy of a herbicide, which is characterized by using a mixture with a resin emulsion (excluding urethane emulsion) at a concentration of 20 to 60% by weight that can form a film having a moisture permeability of .

The herbicides used in the method of the present invention are not particularly limited and vary depending on the target weeds and useful plants, but include isoflovir-N-phenylcarbamate, isoflovir-N-(3-J'rollophenyl ) Carbamate herbicides such as carhamate, α-chloro 4,6-bisethylaminotriazine, 2,4
Phenoxy herbicides such as -D, phenolic herbicides such as pentachlorophenol, fatty acid herbicides such as sodium 2,2-dichloropropionate, 3-(3,4-
urea-based herbicides such as dichlorophenyl)-1,1-dimethylurea, triazine-based herbicides such as 2-chloro-4,6-bis-ethylamino-S-4 riazine, 1-1'
Examples include dipyridyl herbicides such as dimethyl-4,4' dipyridinium ion, and inorganic herbicides such as sodium chlorate and IJium.

In the present invention, moisture permeability means J I SZO 2 0
8, and the resin emulsion used in the method of the present invention has a value of 40
0~1800P/m/24hr (0.03mm thickness)
Any type of material may be used as long as it can form a film having a moisture permeability in the range of .

Moisture permeability is 400? If a resin emulsion that forms a film of less than /m/24 hr is used, a sufficient herbicidal effect cannot be obtained because the degree of elution of the herbicide from the film by rainwater is small.

Also, the moisture permeability is 1800 f! /m/ 2 4 h
When a resin emulsion that forms a film exceeding r is used, it is difficult to sustain the herbicidal effect for a long time (at least half a year) because the degree of elution of the herbicide from the film by rainwater is too large. .

Moisture permeability is 400 to 1800 f? /rtt
The degree of elution of the herbicide by rainwater becomes appropriate only when a resin emulsion that forms a film of '/2 4 hr is used.

In the method of the present invention, the specific resin emulsion containing the above-mentioned herbicide (i.e., in the form of a film as described above) is applied to the object by any method, and at the time of application, the specific resin emulsion containing the herbicide is It only needs to be in the form of a resin emulsion, and any method can be used to form such an emulsion.

For example, the herbicide may be mixed during or after the manufacture of a particular resin emulsion (relatively concentrated stock solution), or the two may be mixed immediately before use.

Usually, a relatively highly concentrated resin emulsion stock solution is prepared and then the herbicide-containing resin emulsion is prepared in a suitable manner for dilution, for example, at the time of application.

A resin emulsion stock solution consists of a resin, water, optionally a solvent such as alcohol, benzene toluene, dimethylformamide, and optionally an emulsifier, certain water-soluble solvents, and one or more of auxiliary agents. Examples include salts of (meth)acrylic acid (alkali metal, ammonium, amine salts), alkylene oxide (those that essentially contain ethylene oxide) adducts of (meth)acrylic acid, water-soluble (meth)acrylic acid, etc. ) A moisture permeability of 400 to 1800, such as a (meth)acrylic (co)polymer that essentially contains an acrylic monomer.
Hydrophilic resins, (meth)acrylic acid esters, (meth)acrylonitrile, (meth)acrylamide, etc. that can form a film of ff /tri'/2 4 hr.
(co)polymers such as meth)acrylic monomers, styrene monomers, vinyl alcohol fatty acid ester monomers,
Moisture permeability 400 ft/7712/24 h, such as polyester resin, natural resin (e.g. rosin), etc.
Examples include resins that form a film with a particle diameter of less than r.

Using a resin that forms a film with a moisture permeability of less than 400 g/'7n''/24 hr, the moisture permeability is 400 to 180.
0? / m2/24 hr To make an emulsion that can form a film, (L) an emulsifier is added in the usual case (although not necessarily, it is generally 30% of the resin).
% by weight or less) (for example, 10 to 2
00% by weight, preferably 20-50% by weight) or (
2) Use of certain water-soluble solvents (e.g. dimethyl sulfoxide, dimethyl formamide, methyl ethyl ketone, butyl alcohol, etc.) or (3) Use of auxiliary agents such as inorganic fillers such as diatomite, calcium carbonate, alumina, etc. to increase moisture permeability from 400 to 18
0 0? A resin emulsion capable of forming a film adjusted to /rn'/2 4 hr may be prepared.

In this case, method (1) is preferable from the viewpoint of long-lasting efficacy of the herbicide.

The concentration (solid content) of the resin emulsion (undiluted solution) is not particularly limited, and may be, for example, 20 to 60% by weight, preferably 40 to 50% by weight.

Further, the emulsifier is not particularly limited and any emulsifier may be used.

In the method of the present invention, a spray solution (herbicide-containing resin emulsion) is usually obtained from the herbicide and resin emulsion stock solution, but as is clear from the above, the manufacturing method is not particularly limited. A method of mixing a fixed amount of herbicide, a predetermined amount of a resin emulsion stock solution, and water for dilution, a method of mixing an aqueous herbicide solution and a resin emulsion stock solution, a method of diluting a resin emulsion stock solution mixed with a herbicide with water, etc. It can be manufactured by various methods.

The amount of herbicide in this spray solution varies depending on the type of herbicide used and the type of target plant, but is usually 0.
The blending amount of the resin emulsion (assuming a solid content concentration of 20 to 60% by weight) is 0.1 to 50% by weight.

Even when the herbicide-containing resin emulsion is prepared by a method other than the method of mixing the herbicide and the emulsion stock solution described above, the composition at the time of spraying is the same as described above.

In addition, the spray amount of the spray liquid is 100 to 30 per 1000 m2.
It is appropriate to select from a range of about 0l.

Methods for dispersing the spray liquid include, for example, spraying, water sprinkling, and foam dispersion, which has been developed in recent years, but are not necessarily limited to these methods.

In the method of the present invention, stabilizers such as emulsion stabilizers and ultraviolet absorbers, preservatives, coloring agents, fillers, spreading agents, and the like can be added as necessary.

By applying the method of the present invention, it is possible to form a resin layer containing a herbicide on the plant body and on the soil surface layer, and to maintain an appropriate amount of the herbicide eluted by rainwater from the resin layer. Therefore, various effects can be expected.

For example, (1) the effectiveness of the herbicide is maintained, so the number of times the herbicide is sprayed is reduced, resulting in significant labor savings.

(2) Since the effectiveness of the herbicide is sustained, the amount of herbicide used ultimately decreases, making it economical.

(3) Improves the adhesion of herbicides to plants and soil, thereby preventing runoff from rainwater, and preventing volatilization into the atmosphere, which occurs with some types of herbicides, significantly increasing the effectiveness of herbicides. can be improved and environmental pollution can be reduced.

(4) Since the method of the present invention uses an emulsion, water and herbicide can be easily mixed.

(5) Since the method of the present invention forms a resin layer on the soil surface layer, it has the effect of keeping the soil warm.

Example 1 100 parts of vinyl acetate/ethylene copolymer emulsion (
Commercially available product; resin content: 55% by weight) (hereinafter referred to as EVA emulsion), 30 parts of polyoxyethylene nonyl phenyl ether nonionic surfactant and 153 parts of water were added, stirred uniformly, and an excess of surfactant than usual was added. EVA with
Emulsion CB) was obtained.

The moisture permeability of the film obtained by evaporating water from this emulsion CB,) is 1.045'? '/771+/2
It was 4 hours.

To 100 parts of this EVA emulsion (B) were mixed 1 part of the herbicide Gramoxone manufactured by Nihon Nohyaku Co., Ltd., 1 part of the herbicide Hiver Xl manufactured by DuPont, and 900 parts of water to obtain a spray liquid-1.

Example 2 100 parts of the EVA emulsion CB) obtained in Example 3 were mixed with 2 parts of Gramoxone, 2 parts of Hyver-X, and 900 parts of water to obtain a spray liquid-2.

Example 3 Stirring rod/nitrogen blow tube thermometer. In a reaction vessel equipped with a dropping device, 243 parts of water, 1 part of polymethacrylate polymer surfactant, and 3 parts of polyoxyethylene nonyl phenyl ether nonionic surfactant were charged, stirred and dissolved,
40 parts of methyl methacrylate, 36 parts of butyl acrylate, 20 parts of butyl methacrylate, and 4 parts of acrylic acid were added dropwise and polymerized using an ammonium persulfate catalyst to form an emulsion CC. 20 parts of dimethyl sulfoxide was added to the mixture and stirred uniformly to obtain an emulsion CD).

The moisture permeability of the film obtained by evaporating water from this emulsion (CD) is 5 6 9 ? /m/24hr.

This emulsion CD) 100 parts K Example 1
Similarly, 1 part of gramoxone and 90 parts of water
0 parts were mixed to obtain a spray liquid-3.

Example 4 10 parts of diatomaceous earth was added to 100 parts of the emulsion CC obtained in Example 3 and stirred uniformly to form an emulsion C.
E) was obtained.

The moisture permeability of the film obtained by evaporating water from this emulsion (CE) is 617? / m2/24 hr.

1 part of gramoxone to 100 parts of this emulsion (CE),
Spray liquid-4 by mixing 1 part of Hiver X and 900 parts of water.
I got it.

Example 5 The spray liquids prepared in Examples 1 to 4 were sprayed by a sprayer at a rate of 2 oOl per 10 ares to each field where weeds were growing.

Thereafter, the dry weight of weeds per 1 m' was checked periodically, and the results are shown in Table 1 along with comparative examples.

Comparative Example 1 is an untreated area, Comparative Example 2 is an area where 2 parts of Gramoxone and 2 parts of Hibar The commercially available EVA emulsion used (the film obtained by evaporating water from this emulsion has a moisture permeability of 369?/m"/24 hr)
In Comparative Example 4, a commercially available acrylic emulsion (from which water was evaporated) was used. The moisture permeability of the film obtained is 1 2 5 ?/m/25 h.
r and the emulsion concentration was 40%.

) 75 parts, 1 part each of Gramoxone and Hyver-X, 92 parts of water
Comparative Example 5 is a hydrophilic urethane emulsion (the moisture permeability of the film obtained from this is 2).
] 32, obtained in Example 8 of JP-A No. 51-1645) 100 parts A spray solution prepared by adding the same herbicide as above to 900 parts of water, Comparative Example 6 was a commercially available water-soluble acrylic resin (80 parts of acrylamide and 2 of a copolymer of 20 parts of sodium acrylate
Comparative Example 7 was a spray solution prepared by adding the same herbicide to 120 parts of 5% aqueous solution and 880 parts of water, and 60 parts of a commercially available terpene resin (YS Resin D [Yasuyu Kogyo Co., Ltd.]), 35 parts of xylene, nonylphenol nonionic The spray solution was a mixture of 5 parts of an activator, the same herbicide as above, and 9 C) O parts of water, and both were sprayed at a rate of 200 liters per 10 ares of test area.

The distribution of weeds in the test plot was approximately 45:30:25 of weeds of the grass family, weeds of the Asteraceae family, and other weeds, and the spraying period was March.

As can be seen from Table 1, the method of the present invention (spray liquid-1 to
4 use) is a comparative method (
This is clearly superior to Comparative Examples 1 to 7 (using the spray liquid).

Example 6 The herbicides used in Examples 1 to 4 (gramoxone, . . . Ivar

The results are shown in Table 2.

The herbicides used were: ■ 2,4D amine salt (a herbicide containing 2,4-dichlorophenoxyacetic acid dimethylamine salt as an effective part, manufactured by Nippon Yakuza Co., Ltd.), ■ Chloro IPC (
Herbicide containing isopropyl N-(3-chlorophenyl)carhamate as an active ingredient, manufactured by Nissan Chemical Co., Ltd.)
Mi ■ Simazine (herbicide containing 2-chloro-4,6-bisethylamino-S-4 riazine as an active ingredient, manufactured by Nippon Kayaku Co., Ltd.), ■ Daupon (effective with 2,2 dichloropropionic acid (soda)) Herbicide containing a certain amount (manufactured by Dow), Romper (weed killer containing N-(2-mercaftethyl)benzenesulfonamide S-(0.O-diisoprobyl phosphorodithioate) as an active ingredient) agent,
As a result of conducting a spraying test in the same manner as in Example 3 except that 1 part of the above herbicide was used in place of 1 part of Gramoxone and 1 part of Hibar Xl in Example 3, all of the above herbicides were The same effect as in Example 3 was obtained with the herbicide.

Claims (1)

[Claims] 1. Herbicide or two or more herbicides and 4. 0 0~1
800? A herbicide characterized by spraying a mixture with a resin emulsion (excluding urethane emulsion) at a concentration of 20 to 60% by weight that can form a film having a moisture permeability of /m/24 hr to form a resin layer. How to maintain its effectiveness.