JP2018065729A - Liquid spraying agent for plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid spray for plants used in the fields of agriculture and horticulture, which has high spreadability and excellent water solubility. A liquid spray agent for plants containing a polyvinyl alcohol-based resin having a saponification degree of 90 mol% or more. [Selection diagram] None

Description

  The present invention relates to a plant liquid spraying agent that is excellent in spreadability and dispersion stability of active ingredients such as agricultural chemicals and fertilizers.

  In the fields of agriculture and horticulture, generally, a fertilizer for promoting growth of fruits and vegetables and an agrochemical for controlling pests are diluted with water and sprayed as they are. However, if the fertilizer or pesticide is diluted with water and sprayed on the plant body in this way, the active ingredient of the fertilizer or pesticide will be washed away due to rain, etc. Sustainability is often impaired.

Therefore, for the purpose of improving the adhesion or spreading property of the active ingredient of fertilizer or agricultural chemical to the plant body, a spreading agent is usually added to the diluting water of fertilizer or agricultural chemical. As spreading agents, polyoxyethylene alkylphenyl ethers and polyoxyethylenes have the properties of lowering the surface tension of the spray liquid and improving the effect of fertilizers and pesticides by improving the adhesion or spreadability to insects and crops that are difficult to wet. Alkyl ethers, polyoxyethylene fatty acid esters, lignin sulfonates, naphthylmethane sulfonates and the like are widely used. However, since they have a property that is very familiar to water, it is not possible to suppress runoff due to rainfall or the like.
In addition, as a spreading agent showing a spreading effect, there are those mainly composed of polyoxyethylene fatty acid ester, paraffin, etc., but the effect is not exhibited unless the use concentration is increased, or the dry film dissolves in water. There is a problem that it remains on the plant forever because it is not. Furthermore, these spreading agents have a problem that all of them have poor solubility in the above-mentioned water dilution solution and do not function unless the blending amount is increased.

In order to solve these problems, a spreadable composition of an agrochemical active ingredient containing polyvinyl alcohol (hereinafter, polyvinyl alcohol is referred to as PVA) has been developed in recent years (see, for example, Patent Document 1).
The PVA described in Patent Document 1 has a saponification degree of about 88 mol%, and has been required to be improved because it has been washed away by rainwater. Then, the liquid spraying agent for agriculture containing 30-60 mol% PVA-type resin is proposed (refer patent document 2).

  However, the agricultural liquid spray described in Patent Document 2 has satisfactory spreadability, but has a problem that the solubility in water is low and the PVA resin precipitates when left for a long time. It was.

JP-A-8-217604 JP-A-2015-134704

  The present invention has been made in view of the above circumstances, and an object thereof is a liquid spraying agent used for plants in agriculture and horticulture, and has a high spreadability on leaf surfaces and the like. Is to provide a liquid spraying agent for plants that does not cause precipitation even when left for a long period of time, that is, has excellent aqueous solution stability.

  The present inventors have found that in the PVA-based resin in the liquid spray agent for plants, by using a resin having a higher saponification degree, the spreadability is excellent and the dispersion stability is also excellent. Completed the invention.

  That is, the gist of the present invention relates to a plant liquid spraying agent containing a PVA resin having a saponification degree of 90 mol% or more.

The plant liquid spraying agent of the present invention is excellent in the spreadability of the active ingredient and the stability of the aqueous solution due to the action of the specific PVA resin in the spraying agent.
Therefore, the liquid spray agent for plants of the present invention is particularly preferably used as a foliar spray agent.

  Since the plant spray of the present invention uses a PVA-based resin having a relatively high saponification degree, it has high hydrophilicity, so it completely dissolves in water, has no precipitation / precipitation, and becomes a film. It is presumed that the high crystallinity suppresses runoff due to rain, and is excellent in spreadability and aqueous solution stability.

The description of the constituent requirements described below is an example (representative example) of an embodiment of the present invention, and is not limited to these contents.
Hereinafter, the present invention will be described in detail.

The plant liquid spraying agent of the present invention contains a PVA resin having a saponification degree of 90 mol% or more.
The saponification degree of the specific PVA-based resin is preferably 91 to 99.5 mol%, more preferably 92 to 99 mol%, further 97 to 99 mol%, particularly 98 to 99 mol%.
If the degree of saponification is too low, spreadability decreases when used as a foliar spray. In addition, the said saponification degree can be analyzed by the alkali consumption required for hydrolysis of residual vinyl acetate according to JISK6726.

  The average degree of polymerization (based on JIS K 6726) of the specific PVA resin used in the plant liquid spray of the present invention is usually 100 to 2000, particularly 150 to 1000, and more preferably 200 to 800. That is, if the average degree of polymerization of the PVA-based resin is too low, the spreadability tends to decrease, and conversely if the average degree of polymerization is too high, the solubility tends to decrease.

  The specific PVA resin can be usually obtained by saponifying a vinyl ester polymer obtained by polymerizing a vinyl ester monomer.

  Examples of the vinyl ester monomers include vinyl formate, vinyl acetate, vinyl trifluoroacetate, vinyl propionate, vinyl butyrate, vinyl caprate, vinyl laurate, vinyl versatate, vinyl palmitate, and vinyl stearate. , Pivalic acid and the like are used alone or in combination of two or more. In practice, vinyl acetate is preferably used from the viewpoint of economy.

The specific PVA resin may be unmodified or modified.
Such a modified PVA resin can be produced by saponifying a polymer of a vinyl ester monomer and another unsaturated monomer, or post-modifying the PVA resin.

Examples of the other unsaturated monomer include vinyl groups and epoxy groups such as glycidyl (meth) acrylate, glycidyl (meth) allyl ether, 3,4-epoxycyclohexyl (meth) acrylate, and allyl glycidyl ether. Monomer: a unit having two or more allyl groups such as triallyloxyethylene, diallyl maleate, triallyl cyanurate, triallyl isocyanurate, tetraallyloxyethane, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate Isomers; allyl ester monomers such as allyl acetate, vinyl acetoacetate, allyl acetoacetate, allyl acetoacetate; acetoacetoxyethyl (meth) acrylate, acetoacetoxypropyl (meth) acrylate, etc. Acetoxyalkyl (meth) acrylate; acetoacetoxyalkyl crotonate such as acetoacetoxyethyl crotonate, acetoacetoxypropyl crotonate; 2-cyanoacetoacetoxyethyl (meth) acrylate; divinylbenzene; ethylene glycol di (meth) acrylate, 1, 2-propylene glycol di (meth) acrylate, 1,3-propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di Alkylene glycol (meth) acrylates such as (meth) acrylate; trimethylolpropane tri (meth) acrylate; allyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate Rate, hydroxypropyl (meth) acrylate, hydroxyalkyl (meth) acrylate such as 4-hydroxybutyl (meth) acrylate (the alkyl moiety is a C1-C10 alkyl group, preferably a C1-C6 alkyl group); (meth) acrylonitrile Nitrile monomers such as styrene, styrene monomers such as α-methylstyrene, olefins such as ethylene, propylene, 1-butene, and isobutene; vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, etc. Halogenated olefin; Olefin monomer such as ethylene sulfonic acid; butadiene-1,3,2-methylbutadiene, 1,3 or 2,3-dimethylbutadiene-1,3, 2-chlorobutadiene-1,3, etc. Diene monomers: 3-buten-1-ol, 4-pentene Hydroxyl group-containing α-olefins such as 1-ol, 5-hexene-1,2-diol, glycerin monoallyl ether, and derivatives thereof such as acylated products thereof; 1,3-diacetoxy-2-methylenepropane, 1,3 -Hydroxymethylvinylidene diacetates such as dipropionyloxy-2-methylenepropane and 1,3-dibutyronyloxy-2-methylenepropane; unsaturated acids such as itaconic acid, maleic acid and acrylic acid, salts thereof or mono Or dialkyl esters; nitriles such as acrylonitrile; amides such as methacrylamide and diacetone acrylamide; compounds such as olefin sulfonic acids such as ethylene sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, and AMPS, or salts thereof, vinyl triethoxy Silane, vinyl Vinylalkyldialkoxysilanes such as rutrimethoxysilane, vinyltripropoxysilane, vinyltributoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane; γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryl Γ- (Meth) acryloxypropyltrialkoxysilane such as loxypropyltriethoxysilane; γ- (meth) such as γ- (meth) acryloxypropylmethyldimethoxysilane, γ- (meth) acryloxypropylmethyldiethoxysilane Examples include acryloxypropylalkyldialkoxysilane; vinyltris (β-methoxyethoxy) silane, and hydroxymethylvinylidene diacetate. Specific examples of hydroxymethylvinylidene diacetate include 1,3-diacetoxy-2-methylenepropane, 1,3-dipropionyloxy-2-methylenepropane, 1,3-dibutyronyloxy-2-methylenepropane. Etc.
In addition, 3,4-dihydroxy-1-butene, 3,4-diasiloxy-1-butene, 3-acyloxy-4-hydroxy-1-butene, 4-acyloxy-3-hydroxy-1-butene, 3,4- Diacyloxy-2-methyl-1-butene, 4,5-dihydroxy-1-pentene, 4,5-diacyloxy-1-pentene, 4,5-dihydroxy-3-methyl-1-pentene, 4,5-diacyloxy- 3-methyl-1-pentene, 5,6-dihydroxy-1-hexene, 5,6-diasiloxy-1-hexene, glycerin monoallyl ether, 2,3-diacetoxy-1-allyloxypropane, 2-acetoxy-1 -Allyloxy-3-hydroxypropane, 3-acetoxy-1-allyloxy-2-hydroxypropane, glycerol monovinyl ether , Glycerol mono isopropenyl ether, vinyl ethylene carbonate, and compounds having a diol such as 2,2-dimethyl-4-vinyl-1,3-dioxolane. These monomers may be used alone or in combination of two or more.

  Examples of the post-modification method include a method in which a PVA resin is esterified with acetoacetate, acetalized, urethanized, etherified, grafted, phosphoric esterified, or oxyalkylenated.

Among the modified PVA resins, an anion modified PVA resin and a nonionic modified PVA resin are particularly preferable because of their high affinity for water. Examples of the anion-modified PVA resin include a carboxyl group-containing PVA resin, a sulfonic acid group-containing PVA resin, and a phosphoric acid group-containing PVA resin. Nonionic modified PVA resins include oxyalkylene group-containing PVA resins, acetoacetyl group-containing PVA resins, diacetone acrylamide modified PVA resins, mercapto group-containing PVA resins, silanol group-containing PVA resins, side chains. 1,2-diol structural unit containing PVA-type resin etc. are mentioned. Of these, oxyalkylene group-containing PVA resins and carboxyl group-containing PVA resins are preferred in terms of alcohol solubility.
The modification | denaturation rate of modified PVA-type resin is a grade which does not impair the aqueous solution of PVA-type resin, and is 0.1-10 mol% normally.

  In addition, as a drug used in the liquid spray agent for plants of the present invention, a drug used as an active ingredient of the spray agent, that is, agrochemical, fertilizer, herbicide, insect repellent, etc. Drugs that require sex are used. Such a chemical can be used as long as it dissolves or disperses in a solvent such as water, but a non-reactive one is used with respect to the specific PVA resin used in the liquid spray agent for plants of the present invention. There is a need to.

  In the liquid spraying agent for plants of the present invention, in addition to a specific PVA resin, a solvent, and a drug, other emulsifiers, wettable powders, flowable agents, surfactants, thickeners, preservatives, etc. Ingredients can be added. However, the blending amount of such other components is preferably 10% by weight or less of the whole plant liquid spray.

  Here, the plant liquid spraying agent of the present invention is, for example, (1) mixing a specific PVA resin solution and a drug solution, (2) mixing a powdered drug in a specific PVA resin solution, ( 3) It can be prepared by a method in which the specific PVA resin powder is mixed in the drug solution and mixed. Especially, it is preferable to prepare by the method shown in (1) from the point of the dispersibility of a chemical | medical agent and the simplicity of preparation.

  Thus, the density | concentration of specific PVA-type resin in the liquid spray agent for plants of this invention obtained in this way is 0.01 to 30 weight% normally, Preferably it is 0.1 to 20 weight%, More preferably, it is 1-10. % By weight. That is, by preparing such a concentration, the spreadability, dispersion stability and the like are improved.

  Further, the concentration of the agent that is the basis of the active ingredient in the plant liquid spray of the present invention is usually 0.1 to 5000 ppm by weight, preferably 1 to 1000 ppm by weight, more preferably 10 to 500 ppm by weight. It is. That is, by preparing such a concentration, the active ingredient of the drug functions effectively.

  And the liquid spray agent for plants of this invention can be used as a spray agent to a leaf surface, a stem surface, the fruit surface, a spray agent for hydroponics, etc. In particular, it is suitably used as a foliar spray.

EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded.
“Parts”, [%] and the like are based on weight.

[Example 1]
<Production of PVA (1)>
A reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer was charged with 1000 parts by weight of vinyl acetate and 345 parts by weight of methanol, and 0.07 mol% of azobisisobutyronitrile (with respect to the charged vinyl acetate) was charged. While stirring, the temperature was raised under a nitrogen stream to initiate polymerization. When the polymerization rate of vinyl acetate reached 89%, a predetermined amount of m-dinitrobenzene was added to complete the polymerization, and then distilled while blowing methanol vapor to remove unreacted vinyl acetate monomer. Removal from the system gave a methanol solution of the copolymer. Next, the methanol solution was adjusted to a concentration of 55% and charged into a kneader. While maintaining the solution temperature at 40 ° C., a 2% methanol solution of sodium hydroxide was added to 1 mol of vinyl acetate structural units in the copolymer. Saponification was carried out at a rate of 2 mmol. When saponification progresses as saponification progresses and particles are formed, 0.8 equivalent of sodium hydroxide is added to neutralization acetic acid, filtered, washed well with methanol, and heated in a hot air dryer To obtain unmodified PVA (1).
The degree of saponification of the obtained PVA (1) was 99 mol% when analyzed by the alkali consumption required for hydrolysis of residual vinyl acetate, and the average degree of polymerization was analyzed according to JIS K6726. As a result, it was 500.

  PVA (1) obtained as described above was dissolved in water to prepare a 5% strength PVA solution. And liquid fertilizer (Sumitomo Chemical Horticultural Co., Ltd. make, ortran wettable powder) was diluted to the designated density | concentration to 100 weight part of this PVA aqueous solution, 5 parts was added, and the liquid spray agent for plants was prepared.

[Example 2]
In Example 1, it replaced with PVA (1) and performed similarly except having used PVA (2) of saponification degree 93 mol% and average degree of polymerization 700. The results are shown in Table 1.

[Comparative Example 1]
In Example 1, it replaced with PVA (1) and performed similarly except having used PVA (3) of saponification degree 49 mol% and average polymerization degree 250. The results are shown in Table 1.

[Comparative Example 2]
In Example 1, it replaced with PVA (1) and carried out similarly except having used PVA (4) with a saponification degree of 34 mol% and an average degree of polymerization of 300. The results are shown in Table 1.

[Comparative Example 3]
In Example 1, it replaced with PVA (1) and it carried out similarly except having used PVA (5) of saponification degree 88 mol% and average polymerization degree 600. The results are shown in Table 1.
The following evaluation was performed about the liquid spray agent for plants obtained by said Example and comparative example.

[Evaluation of spreadability]
After adding 0.1 part of coloring agent (food red) to 105 parts of the liquid spraying agent for plants, the liquid spraying agent for plants was sprayed on the leaf surface of the plant (Benjamin Esta) by spraying. And after leaving to stand for 24 hours, water was sprayed on the foliage surface (spreading surface of the liquid spraying agent for plants) by spraying. Then, the colored surface remaining without dropping was visually observed, and the colored surface was evaluated as “◯” when 80% or more remained with respect to the area of the leaf surface (dispersed surface of the liquid spray agent for plants). In addition, what remained 30% or more and less than 80% with respect to the area of a leaf surface (spreading surface of the liquid spray agent for plants) was evaluated as "(triangle | delta)", and what remained less than 30% was evaluated as "x".

[Dispersion stability evaluation]
After preparing the plant liquid spray, it was allowed to stand at room temperature for 4 days. The state after standing was visually observed, and the dispersed one was evaluated as “◯”, and the one where precipitation occurred was evaluated as “×”.

  Examples 1 and 2 using the plant spray of the present invention were excellent in spreadability and dispersion stability. On the other hand, Comparative Examples 1 and 2 with a very low saponification degree are excellent in spreadability but inferior in dispersion stability, and Comparative Example 3 with a slightly low saponification degree is also excellent in dispersion stability. The spreadability was inferior.

  The plant liquid spraying agent of the present invention has high spreadability and excellent dispersion stability due to the action of the specific PVA resin, and therefore, a plant liquid spraying agent used in the fields of agriculture and horticulture, for example, It is useful for application to spraying agents on leaf surfaces, stem surfaces, fruit surfaces, etc.

Claims (3)

  A plant liquid spraying agent comprising a polyvinyl alcohol resin having a saponification degree of 90 mol% or more.   The liquid spray agent for plants according to claim 1, wherein the polyvinyl alcohol resin has an average degree of polymerization of 100 to 2,000.   The plant liquid spraying agent according to claim 1 or 2, wherein the plant liquid spraying agent is a foliar spraying agent.