JP2011153118A - Aqueous emulsion type herbicide composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous emulsion type herbicide composition excellent in emulsion stability, reduced in odor characteristic to pelargonic acid having herbicidal activity, exhibiting effect on a wide variety of kinds of weeds when sprayed thereover, very low in load on humans and the environment. <P>SOLUTION: The herbicide composition is prepared by formulating pelargonic acid and/or a pelargonate salt and/or pelargonic acid ester as a herbicidal active ingredient with a vinyl alcohol/vinyl acetate copolymer, a fatty acid ester type nonionic surfactant, and an odor modifier. It is desirable that the vinyl alcohol/vinyl acetate copolymer is a polyvinyl alcohol having an average degree of polymerization of 1,000 or smaller, viscosity of 1-20 mPa in a 4% solution at 20°C, and a degree of saponification of 80-90 mol%. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an aqueous emulsion type herbicide composition.

Weed breeding is inevitable in home gardening fields such as ornamental gardening that enjoys the growth of flowering plants, ornamental trees and flowering trees, and production gardening that enjoys harvesting fruit trees and vegetables. Leaving these weeds not only deprives the growing flowers and crops of nutrients, but in the worst case, depending on the overgrowth situation, the accompanying animals, insects and arthropods such as spiders that feed on them Even small animals such as animals, small mammals such as mice, and small birds can become a cause of getting closer to the living environment.
Therefore, various herbicides by chemical synthesis such as phenoxy, bipyridinium, urea, sulfonylurea, triazine, nitrile, uracil, and carbamate are used as herbicidal means for removing these weeds. It has been.
However, because of their toxicity, these chemical herbicides are not only a direct health hazard to workers, but also have an indirect effect on human beings that are part of the food chain ring starting with soil and groundwater.

  Thus, fatty acids having a specific number of carbon atoms, particularly straight-chain fatty acids, have attracted attention as substances having practical herbicidal activity against a wide range of grass species and having extremely low effects on the human body and the environment. In particular, linear saturated fatty acids having 8 to 12 carbon atoms (caprylic acid having 8 carbon atoms, pelargonic acid having 9 carbon atoms, capric acid having 10 carbon atoms, lauric acid having 12 carbon atoms) are cuticular wax layers such as broad-leaved weeds. It is known to exhibit excellent herbicidal activity by destroying In addition, the linear saturated fatty acid is rapidly decomposed by microorganisms in the soil at the same time, so even if it is used in the immediate vicinity of useful plants, it is absorbed from the roots like other soil-absorbing herbicides and becomes useful plants. There is no worry of causing phytotoxicity. Of these linear fatty acids, pelargonic acid exhibits the strongest herbicidal activity. In situations where there is a possibility that useful plants and weeds may coexist in a relatively small area, such as home gardening, it is very easy to remove only weeds by spraying pelargonic acid locally with hand spray etc. It is.

However, pelargonic acid has a very strong and specific pungent odor and is a major obstacle when used in the field of home gardening. At the same time, although acute toxicity is very low, it has mild to moderate skin irritation and eye irritation, so it is difficult to apply pelargonic acid alone to plants.
Therefore, an attempt to use pelargonic acid as an aqueous emulsion preparation using a water-soluble polymer and a surfactant such as sucrose fatty acid ester (Patent Document 1), and simultaneous use of potassium pyrophosphate as an emulsion or wettable powder There is an attempt to use it as an emulsion or a wettable powder in combination with ethylenediaminetetraacetate (Patent Document 2), but finally to improve the above-mentioned very strong specific irritating odor. Has not reached.
Pelargonic acid is a water-insoluble fatty acid having a carboxylic acid group in its structure. In general, it is very difficult to uniformly emulsify a fatty acid having 10 or less carbon atoms in water. In fact, when diluting a pelargonic acid emulsion sold as “Grantrico Emulsion” (manufactured by JT) in water, The cream layer separates in about 10 minutes. Therefore, even if this water-diluted preparation of pelargonic acid emulsion is filled in a hand spray and sprayed with stirring, it is considered very difficult to spray uniformly over a long period of time.
In order to use various pesticidal active ingredients such as insecticides or fungicides as aqueous preparations, there is also an attempt to make an aqueous emulsion preparation by combining a water-soluble polymer compound and sorbitan monooleate (Patent Document 4). However, it has a relatively high viscosity at 20 ° C. of 100 to 1000 mPa · s, and is unsuitable for the purpose of a pelargonic acid-containing herbicide that needs to diffuse quickly to the ground of the plant after spraying.
Furthermore, an attempt is made to produce an aqueous suspension preparation for direct spraying in a flooded sewage paddy field composed of a herbicidal active ingredient having a solubility in water at 20 ° C. of 100 ppm or less, a protective colloid agent, a high boiling point solvent, and water (Patent Document 5). However, this method is suitable for an agrochemical active ingredient that is solid at 20 ° C., but is substantially free of an emulsifying component and contains only a protective colloid agent. Therefore, even if pelargonic acid is applied, the oil droplet particle system of pelargonic acid formed is large, which is not suitable from the viewpoint of the storage stability of the preparation.

Japanese Patent Application Laid-Open No. 6-211603 JP 7-215805 A JP 7-215806 A JP 2007-145754 A Japanese Patent Laid-Open No. 11-158006

  The object of the present invention is to improve the odor peculiar to pelargonic acid having excellent emulsification stability and herbicidal activity, and exerting effects on a wide variety of weeds by spraying, and the burden on the human body and the environment is very low Another object is to provide an aqueous emulsion type herbicide composition.

  As a result of intensive studies to solve the above problems, the present inventors have found that an aqueous emulsion type herbicidal composition containing pelargonic acid, a salt thereof, and an ester thereof as a herbicidal active ingredient, a vinyl alcohol-vinyl acetate copolymer It has been found that the inclusion of a fatty acid ester type nonionic surfactant and an odor improving agent contributes to solving the desired problem, and the present invention has been made based on this finding.

That is, the present invention is as follows.
(1) Using pelargonic acid and / or pelargonate and / or pelargonic acid ester as a herbicidal active ingredient, and further comprising a vinyl alcohol-vinyl acetate copolymer, a fatty acid ester type nonionic surfactant, and an odor improving agent A water-based emulsion herbicide composition, which is formulated.
(2) The vinyl alcohol-vinyl acetate copolymer is polyvinyl alcohol having an average degree of polymerization of 1000 or less, a viscosity of a 4% aqueous solution at 20 ° C. of 1 to 20 mPa, and a saponification degree of 80 to 90 mol%. An aqueous emulsion herbicide composition as described in 1).
(3) The aqueous emulsion herbicide composition according to (1) or (2), wherein the fatty acid ester type nonionic surfactant is a sorbitol fatty acid ester having an HLB of 10 to 14.
(4) The aqueous emulsion herbicide composition according to (3), wherein the sorbitol-based fatty acid ester is a polyoxyethylene sorbitol tetraoleate in which 20 mol or more of ethylene oxide is added in one molecule.
(5) The aqueous emulsion type herbicide composition according to any one of (1) to (4), wherein the odor improving agent is a natural plant essential oil.
(6) The aqueous emulsion herbicide composition according to (5), wherein the natural plant essential oil is a terpene aldehyde.
(7) Polyvinyl alcohol and ethylene oxide having an average polymerization degree of 1000 or less, a viscosity of 4% aqueous solution at 20 ° C. of 1 to 20 mPa, and a saponification degree of 80 to 90 mol% are obtained by using pelargonic acid as a herbicidal active ingredient. An aqueous emulsion type herbicide composition comprising polyoxyethylene sorbitol tetraoleate added in an amount of 30 mol or more in the molecule, citronellal and water, and having a viscosity at 25 ° C. of 10 to 50 mPa · s.
(8) A herbicidal method in which an effective amount of the aqueous emulsion herbicidal composition according to any one of (1) to (7) is applied to weeds.

The aqueous emulsion type herbicidal composition of the present invention is excellent in versatility, environmental safety and human safety, has an excellent effect that it can be applied to a wide variety of weeds with improved odor characteristic of pelargonic acid.
In addition, the aqueous emulsion type herbicide composition of the present invention can be easily sprayed with a wide range of hand-sprays without worrying about phytotoxicity to useful plants that are generated by root absorption after soil transfer or soil transfer. It can be applied directly to weeds for weeding.

Pelargonic acid, pelargonate or pelargonic acid ester (hereinafter referred to as pelargonic acid) having a very strong herbicidal activity as a herbicidal active ingredient in the aqueous emulsion herbicide composition of the present invention (hereinafter also referred to as the present composition). Etc.) is also used. Examples of pelargonic acid salts include alkali metal salts such as potassium and sodium, and examples of pelargonic acid esters include methyl esters and ethyl esters.
The content ratio of pelargonic acid and the like in the composition of the present invention is usually selected in the range of 1 to 50% by weight, preferably 1 to 20% by weight. Deviating from this range is not preferable from the viewpoints of cost and efficacy, irritation to the user's skin and eyes, and the like.

The vinyl alcohol-vinyl acetate copolymer used in the composition of the present invention is a polymer compound generally obtained by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate with alkali, acid, ammonia or the like. It is commercially available as polyvinyl alcohol. Polyvinyl alcohol has different properties depending on the average degree of polymerization and the degree of saponification (saponification degree). In the present invention, the average degree of polymerization is preferably 1000 or less, and the viscosity of a 4% aqueous solution at 20 ° C. is 1 to 20 mPa. The saponification degree is 70 to 90 mol%, more preferably the viscosity of a 4% aqueous solution at 20 ° C. is 1 to 10 mPa · s and the saponification degree is 80 to 90 mol%. If the degree of saponification exceeds 90 mol%, the solution viscosity tends to be slightly high, and the solubility in water becomes extremely poor during use.
Commercially available products such as GOHSENOL GL-05 (manufactured by Nippon Synthetic Chemical Co., Ltd.), GOHSENOL KL-05 (manufactured by Nippon Synthetic Chemical Co., Ltd.), and the like can be used as the polyvinyl alcohol as the polyvinyl alcohol.
The content ratio of the vinyl alcohol-vinyl acetate copolymer in the composition of the present invention is usually 0.5 to 6% by weight, preferably 1 to 5% by weight, based on the composition of the present invention.

In addition, the fatty acid ester type nonionic surfactant (hereinafter also referred to as the present nonionic surfactant) used in the composition of the present invention is used to reduce the particle size of oil droplets and thereby improve the uniformity of the preparation. Those effective and having a hydrophilic / hydrophobic balance (so-called HLB) in the range of 9 to 20, especially 10 to 14, particularly sorbitol fatty acid esters are preferred. Examples of sorbitol fatty acid esters include poly Examples thereof include oxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, and polyoxyethylene sorbitol fatty acid ester. These may be used alone or in combination of two or more.
Of these nonionic surfactants, polyoxyethylene sorbitol fatty acid esters are preferred in order to reduce the oil droplet particle size of the aqueous emulsion preparation and to make the components uniform.
In the polyoxyethylene sorbitol fatty acid ester, ethylene oxide is preferably added in an amount of preferably 20 moles or more, more preferably 30 moles or more, particularly preferably 30 to 60 moles in one molecule. Examples thereof include those corresponding to polyoxyethylene sorbitol tetrastearate and polyoxyethylene sorbitol tetraoleate. Examples of commercially available products include “Reodol 430V”, “Leodol 440V”, “Leodol 460V”, and Nikko Chemical. “Nikkor GS-460” “Nikkor GO-430NV” “Nikkor GO-440V” “Nikkor GO-460V”, etc.
The content ratio of the fatty acid ester type nonionic surfactant in the composition of the present invention is usually selected in the range of 0.1 to 10% by weight, preferably 0.5 to 3% by weight. If it deviates from this range, it is not preferable in terms of cost, the stimulation of the surfactant itself increases, and it is not preferable from the viewpoint of safety to the user.

As described above, pelargonic acid which is an herbicidal active ingredient in the aqueous emulsion type herbicidal composition in the present invention has a unique odor, which is presumed to be an inhibiting factor for easy use by general consumers. The
The odor improving agent used in the composition of the present invention is effective in changing the odor to an aromatic one and presenting a mild citrus fragrance.
As this odor improving agent, a natural plant essential oil is preferably used, more preferably a terpene aldehyde contained in the essential oil. Natural plant essential oils are volatile oils based on terpene compounds and are called essential oils because they have completely different properties from oils such as rapeseed oil and coconut oil. For example, citronella oil, bay (bay leaf) oil, cinnamon oil, cinnamon oil, coriander oil, cumin oil, estragon oil, eucalyptus oil, fennel oil, lemon oil, lemongrass oil, lime oil, Lycea cubeba oil, Mandarin oil, tangerine oil, mimosa oil, mill oil, nasissus oil, orange oil, palmarosa oil, perilla oil, etc., but terpene aldehydes are included, lemongrass oil, citronella oil, lysacecube oil Lemon oil, lemongrass oil, lime oil, mandarin oil, tangerine oil, range oil and the like are preferable.
Examples of the terpene aldehyde include terpene aldehydes extracted from essential oils, such as citral, citronellal, and perilaldehyde, and citronellal is the most suitable from the viewpoint of availability and cost.
The content ratio of the odor improving agent in the composition of the present invention is usually selected in the range of 0.1 to 20% by weight, preferably 0.5 to 10% by weight, more preferably 1 to 6% by weight. If it deviates from this range, it is not preferable from the viewpoint of cost and efficacy because the perfume odor becomes stronger and the effect of addition becomes difficult to be exhibited.

In addition, water is used in the composition of the present invention to form an aqueous emulsion. The water may be so-called soft water or hard water, and ion-exchanged water, distilled water or the like can also be used. The water preferably has an electrical conductivity of 2 μS / cm or less and an electrical resistance of 0.5 MΩ or more.
The ratio of the oil phase and the aqueous phase containing the active ingredient in the composition of the present invention is usually selected in the range of 1:50 to 1: 2, preferably in the range of 1:40 to 1: 3.
Particularly preferred as the composition of the present invention is that pelargonic acid is used as a herbicidal active ingredient, the average degree of polymerization is 1000 or less, the viscosity of a 4% aqueous solution at 20 ° C. is 1 to 20 mPa, and the degree of saponification is 70 to 90 mol%. Aqueous emulsion type herbicide containing polyoxyethylene sorbitol tetraoleate, citronellal and water with 30 mol or more of polyvinyl alcohol and ethylene oxide added in one molecule, and having a viscosity at 25 ° C. of 10 to 50 mPa · s. Agent composition. The viscosity is measured with a Brookfield viscometer (LV system, 60 rpm).

In the composition of the present invention, a surfactant other than the present nonionic surfactant, a viscosity modifier, an antifoaming agent, an antifreezing agent, a preservative, and a stabilization, as long as the purpose of the present invention is not impaired, if necessary. Optional additives such as a colorant, a colorant, an efficacy enhancer, and a safener can be included.
Among these optional additives, surfactants include, for example, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl phenyl ether / formalin condensate, ethylene oxide / propylene oxide / block polymer, polyalkyl Nonionic surfactants such as ethylene oxide modified silicone oil, alkyl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfate, polyoxystyryl phenyl ether sulfate, dialkyl sulfosuccinate, alkyl benzene sulfonate, mono Alkyl naphthalene sulfonate, dialkyl naphthalene sulfonate, naphthalene sulfonate Formalin condensates, alkyl diphenyl E over ether Soo Gandolfo sulfonate, nonionic surfactants such as polyoxyethylene alkyl phenyl ether sulfonates and the like.

Examples of the viscosity modifier include natural polysaccharides such as xanthan gum, rhamzan gum, locust bean gum, guar gum, carrageenan, welant gum, alginic acid, alginates and tragacanth gum; synthetic polymers such as sodium polyacrylate; semi-polymers such as carboxymethylcellulose Examples thereof include synthetic polymers; mineral powders such as aluminum silicate, magnesium aluminum silicate, smectite, bentonite, hectorite, synthetic hydrous silicic acid, and dry silica; and alumina sol.
Commercially available products can be used as they are as viscosity modifiers. Examples of xanthan gum include Kelzan S (manufactured by Sanki Co., Ltd.), examples of aluminum silicate include Veegum R (manufactured by Vanderbilt), and examples of dry silica include aerosil. 200 (manufactured by Degussa Huls), and examples of the mixture of dry silica and alumina sol include Aerosil COK-84 (manufactured by Degussa Huls).
Antifoam C (manufactured by Dow Corning), antifoam CE (manufactured by Dow Corning), TSA730 (manufactured by Toshiba Silicone), TSA731 (manufactured by Toshiba Silicone), TSA732 (Toshiba) Silicone-based antifoaming agents such as YMA6509 (manufactured by Toshiba Silicone); and fluorine-based antifoaming agents such as Fluorowet PL80 (manufactured by Clariant).

The composition of the present invention can be produced, for example, by the following method.
The predetermined fatty acid, natural plant essential oil, and the present nonionic surfactant are mixed to prepare a uniform oil phase solution containing the predetermined fatty acid. Separately, a vinyl alcohol-vinyl acetate copolymer and water are mixed, heated if necessary, and an antifoaming agent is added if necessary to prepare an aqueous phase solution containing the vinyl alcohol-vinyl acetate copolymer. Next, the oil phase solution and the aqueous phase solution are emulsified and dispersed to produce the composition of the present invention. If necessary, the manufactured composition of the present invention may further contain the above-mentioned viscosity modifier, antifreezing agent, preservative, stabilizer, and coloring agent. As a method of emulsifying and dispersing, for example, a mechanical dispersion method for compulsorily dispersing with mechanical energy is used.
As a mechanical dispersion method, a special method in which a fatty acid-containing oil phase solution is forcibly emulsified and dispersed in water by a high mechanical shear force (for example, the oil phase solution is sprayed from the pores into the aqueous phase at a high speed to be shielded). Microfluidizers that collide with the plate, bead mills that are emulsified by stirring at high speed with grinding media such as glass beads, colloid mills that are forced to pass through narrow gaps and are emulsified by the shearing force generated at that time are also conceivable. A method using a general homomixer or disperser is sufficient, and an aqueous emulsion herbicide composition having a uniform initial particle size of 1 μm or less and excellent in storage stability can be obtained.

  In general, the composition of the present invention may be applied directly to weeds to be controlled using hand spray or the like, and the application method is preferably by direct application.

  EXAMPLES Hereinafter, although an Example and a test example are given and this invention is demonstrated in more detail, this invention is not limited at all by these examples.

Example 1
(I) Preparation of oil phase To a mixture of 10 parts by weight of pelargonic acid (nonanoic acid reagent grade 1, reagent manufactured by Kanto Chemical Co., Ltd.) and polyoxyethylene [40] sorbitol tetraoleate (trade name: Rhedol 440V 1 part by weight), an isoparaffin solvent (Product name: IP Solvent, manufactured by Idemitsu Kosan Co., Ltd.) 10 parts by weight, Citronellal extract (natural extract manufactured by OM Scientific Co., Ltd.), 4 parts by weight successively, Tokyo Rika Kikai Co., Ltd .: Magella Z-2110, 400 rpm The oil phase was prepared by uniformly dispersing at room temperature by stirring for 5 minutes for each component.
(Ii) Preparation of aqueous phase Further, 4 parts by weight of Gohsenol GL-05 (manufactured by Nippon Synthetic Chemical Co., Ltd.) and 71 parts by weight of ion-exchanged water heated and kept at 70 ° C. were added to 400 rpm using the agitator. For 15 minutes to prepare an aqueous phase.
(Iii) Preparation of aqueous emulsion type herbicide composition The aqueous phase of (ii) was cooled to room temperature, taken into a 300 ml stainless beaker, stirred at 1200 rpm with the mixer, and the oil phase of (i) was added to 1 ml / After the addition was completed, the mixture was further stirred at room temperature for 1 hour, and the viscosity at 25 ° C. (measured with Brookfield viscometer (LV system, spindle No. 3, 60 rpm)) was 25 mPa · s. An emulsion type herbicide composition (1) was obtained.
This herbicidal composition had a volume median particle diameter of 0.8 μm when the emulsified particle diameter was measured with SALAD-300V manufactured by Shimadzu Corporation, and the smell of pelargonic acid was not felt.

Example 2
Except for changing the amount of the citronellal extract to 2.0 parts by weight, the viscosity at 25 ° C. [measured with Brookfield viscometer (LV system, spindle No. 3, 60 rpm)] was 23 mPa as in Example 1. S aqueous emulsion type herbicide composition (2) was obtained.
The herbicide composition had a volume-median particle diameter of 1.0 μm when the emulsified particle diameter was measured in the same manner as in Example 1, and the pelargonic acid odor was not felt.

Comparative Example 1
After preparing an oil phase in the same manner as in Example 1, 0.2 part by weight of acrylic acid polymer emulsifier (trade name: Peshren TR-2, manufactured by Lubrizol), 74.5 parts by weight of ion-exchanged water, Was stirred for 30 minutes at 400 rpm at room temperature using the above stirrer to prepare an aqueous phase. While stirring the aqueous phase, the oil phase was added at 1 ml / min at 600 rpm at room temperature, and the stirring was continued for 30 minutes. Then, 0.3 parts by weight of triethanolamine was added under the same conditions to obtain a comparative herbicidal composition (1).
This comparative herbicidal composition had a volume-median particle size of 2.0 μm and a strong pelargonic odor.

Comparative Example 2
A comparative herbicide composition (2) was obtained by diluting 10 parts by weight of “Gran Torico Emulsion” (an emulsion containing 52% pelargonic acid) with 90 parts by weight of ion exchange water.
This comparative herbicidal composition had a volume-median particle size of 2.0 μm and a strong pelargonic odor.

Test Example 1 (Stability of herbicide composition)
Using the herbicidal compositions of Examples and Comparative Examples as test samples, placing them in a 100 ml glass container, allowing them to stand at room temperature, measuring the time until the oil phase separates, and redispersibility after separation Was determined according to the following evaluation criteria.
Very good: No more than 5 times of overturning stirring until the storage container is overturned with stirring (stirring speed 1 time / second) and uniformly redispersed (visual appearance) Good: The number of overturning stirring is 6 to 10 times slightly poor: Table 1 shows the test results that are not uniform even when the number of overturned stirrings is 11 to 20 times poor.

  Thus, the herbicidal compositions of the examples are very stable compared to existing products containing pelargonic acid, and can be used as an AL (abbreviation of “Applicable Liquid”) formulation. There was found.

Test example 2
The herbicidal composition of Example 1 is filled in a hand spray bottle and sprayed to various weeds shown below at 100 ml / m ^2, and the herbicidal effect on the third day after spraying is determined according to the following evaluation criteria. A weeding test was conducted.
◎: More than 90% of the area is killed ○: More than 80% of the area is killed △: More than 50% of the area is killed ×: Less than 30% of the killed area For comparison, as an existing herbicide A herbicidal test similar to the above was performed using a 100-fold diluted solution of a buster formulation (containing 18.5 parts by weight of glufosinate) manufactured by Bayer CropScience.
The test results are shown in Table 2.

  From this, it can be seen that the herbicidal compositions of the examples can be applied to a wide variety of weeds.

  The aqueous emulsion type herbicidal composition of the present invention is excellent in versatility, environmental safety, human safety, pelargonic acid-specific odor is improved, and can be applied to a wide variety of weeds, When using it, it can be applied directly to a wide variety of weeds without worrying about phytotoxicity to useful plants caused by soil absorption or root absorption by spreading by hand spray, It is very useful in industry.

Claims (8)

  Using pelargonic acid and / or pelargonate and / or pelargonic acid ester as a herbicidal active ingredient, and further blending a vinyl alcohol-vinyl acetate copolymer, a fatty acid ester type nonionic surfactant, and an odor improving agent An aqueous emulsion type herbicide composition.   The vinyl alcohol-vinyl acetate copolymer is polyvinyl alcohol having an average degree of polymerization of 1000 or less, a viscosity of a 4% aqueous solution at 20 ° C of 1 to 20 mPa, and a saponification degree of 80 to 90 mol%. An aqueous emulsion type herbicide composition.   The aqueous emulsion herbicide composition according to claim 1 or 2, wherein the fatty acid ester type nonionic surfactant is a sorbitol fatty acid ester having an HLB of 10 to 14.   The aqueous emulsion type herbicide composition according to claim 3, wherein the sorbitol-based fatty acid ester is a polyoxyethylene sorbitol tetraoleate in which 20 mol or more of ethylene oxide is added in one molecule.   The aqueous emulsion type herbicide composition according to any one of claims 1 to 4, wherein the odor improving agent is a natural plant essential oil.   6. The aqueous emulsion herbicide composition according to claim 5, wherein the natural plant essential oil is a terpene aldehyde.   Polyvinyl alcohol and ethylene oxide are used in which one molecule is pelargonic acid, a herbicidal active ingredient, an average polymerization degree of 1000 or less, a viscosity of a 4% aqueous solution at 20 ° C. of 1 to 20 mPa, and a saponification degree of 80 to 90 mol%. An aqueous emulsion type herbicide composition comprising polyoxyethylene sorbitol tetraoleate added in an amount of 30 mol or more, citronellal and water, and having a viscosity at 25 ° C. of 10 to 50 mPa · s.   A herbicidal method wherein an effective amount of the aqueous emulsion type herbicidal composition according to any one of claims 1 to 7 is applied to weeds.