TW202216963A - Resin emulsion spraying liquid, and resin emulsion spraying liquid evaluation method - Google Patents

Abstract

Provided is a resin emulsion spraying liquid which can be easily sprayed using a spraying device and which does not easily cause clogging of a nozzle of the spraying device during spraying. The present invention is capable of providing the resin emulsion spraying liquid configured so that: viscosity is 100mPa.s or less when measured at a temperature of 30 DEG C and a rotation rate of 30rpm; and mechanical stability is 1.0% or less as a result of subjecting the spraying liquid to a test with a Malone mechanical stability measurement device at 20 DEG C under a load of 10kgf at 1000rpm for 5 minutes, and thereafter filtering the same through a 100 mesh stainless steel net, the mechanical stability being calculated using the formula below. Mechanical stability (%) = filtration residue (g)/resin emulsion spraying liquid solid content (g)*100.

Description

Resin Emulsion Dispersion, Evaluation Method for Resin Emulsion Dispersion

The present invention relates to a resin emulsion dispersion solution and a method for evaluating the resin emulsion dispersion solution.

Because the coal, coke, ore, coal ash and soil of construction sites and quarries in steel mills and thermal power plants are usually stored in the open air, the air will be mixed with fine dust under the action of wind, which will cause the deterioration of the working environment and surrounding environment, and the existence of soil and water. Erosion and soil erosion problems, such as the erosion of the topsoil by rainwater, which flows at the same time as the rainwater.

Therefore, in order to prevent the generation of dust, soil erosion and loss, a method of spraying a resin emulsion on the soil surface to form a thin film is known.

As the resin emulsion, water-soluble emulsions obtained by copolymerizing vinyl-based monomers such as acrylates and ethylene that can be copolymerized with vinyl acetate have been conventionally used (for example, refer to Patent Document 1). [Prior Art Literature]

Patent Document 1: Japanese Patent Laid-Open No. 2019-052289

[The problem to be solved by the invention]

In the prior art, when the resin emulsion dispersion liquid is dispersed using a dispersion device, the dispersion may be difficult or the nozzle of the dispersion device may be blocked.

The present invention has been made in view of the above-mentioned problems, and provides a resin emulsion dispersion liquid that can be easily dispersed using a dispersion device and that is less likely to clog a nozzle of the dispersion device during dispersion. [Scheme for problem solving]

That is, the present invention is as follows. (1) A resin emulsion dispersion liquid having a viscosity of 100 mPa s or less measured at a temperature of 30°C and a rotational speed of 30 rpm, and subjected to a MARON mechanical stability measuring device at 20°C and a load of 10 kg for 5 minutes at 1000 rpm After the test, filter with a 100-mesh stainless steel wire mesh, and the mechanical stability calculated by the following formula is 1.0% or less: mechanical stability (%) = filtration residue (g)/solid content of resin emulsion dispersion liquid (g) × 100. (2) The resin emulsion dispersion liquid described in (1), which comprises a water-soluble resin emulsion. (3) The resin emulsion dispersion liquid described in (1) or (2), wherein the water-soluble resin emulsion is an emulsion containing a resin derived from a vinyl acetate-derived structural unit. (4) The resin emulsion dispersion liquid according to any one of (1) to (3), wherein the water-soluble resin emulsion is an emulsion containing an ethylene-vinyl acetate copolymer. (5) The resin emulsion dispersion liquid according to any one of (1) to (4), which is used as a dispersion liquid for preventing dust. (6) The resin emulsion dispersion liquid according to any one of (1) to (4), which is used as a dispersion liquid for preventing soil loss. (7) a manufacturing method of a resin emulsion dispersion liquid, which comprises an ethylene-vinyl acetate copolymer emulsion manufacturing step, in the above-mentioned ethylene-vinyl acetate copolymer emulsion manufacturing step, with respect to the input amount of vinyl acetate monomer 100 mass Add 2-10 parts by mass of emulsifier, carry out a test for 5 minutes at 1000 rpm at 20° C. under a load of 10 kg by a MARON type mechanical stability measuring device, filter with a 100-mesh stainless steel wire mesh, and calculate by the following formula The mechanical stability is 1.0% or less, and the viscosity measured at a temperature of 30°C and a rotation speed of 30rpm is 100mPa･s or less: Mechanical stability (%)=filtration residue (g)/solid content of resin emulsion dispersion liquid (g)×100. (8) A method for evaluating a resin emulsion dispersion liquid, comprising a viscosity measurement step, a mechanical stability calculation step, and a determination step, wherein in the above-mentioned viscosity measurement step, the viscosity of the above-mentioned resin emulsion dispersion liquid is measured, and in the above-mentioned mechanical stability calculation step , with above-mentioned resin emulsion dispersion liquid by MARON type mechanical stability measuring device at 20 ℃, under the load of 10kg, after carrying out the test for 5 minutes with 1000rpm, filter with 100 mesh stainless steel wire mesh and calculate the mechanical stability by the following formula: Mechanical stability (%) = filtration residue (g)/solid content of resin emulsion dispersion liquid (g) × 100 In the above determination step, it is determined whether or not the viscosity is 100 mPa·s or less, and whether the mechanical stability is 1.0% or less. [Inventive effect]

ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the resin emulsion dispersion liquid which can be easily sprayed using a spraying device, and the nozzle of the spraying device is not easily clogged at the time of spraying.

The resin emulsion dispersion liquid of the present invention is subjected to a test (load test) at 20° C. under a load of 10 kg at 1000 rpm for 5 minutes by a MARON type mechanical stability measuring device, and then filtered with a 100-mesh stainless steel wire mesh. The calculated mechanical stability is 1.0% or less. Mechanical stability (%) = filtration residue (g)/solid content of resin emulsion dispersion liquid (g) × 100 (1).

In addition, the viscosity of the resin emulsion dispersion liquid measured at a temperature of 30° C. and a rotational speed of 30 rpm was 100 mPa·s or less. As the viscometer, for example, a rotational viscometer, preferably a B-type rotational viscometer, can be used.

The mechanical stability calculated by the above formula (1) is insufficient, and in the resin emulsion dispersion liquid in which the mass of the filtration residue after the load test exceeds 1 mass % with respect to the solid content of the resin emulsion dispersion liquid, it may occur during the dispersion operation. Nozzle of dispenser is clogged. The ratio of the above-mentioned formula (1) of the solid content of the filtration residue after the load test and the resin emulsion dispersion liquid is preferably 0.8% or less, and more preferably 0.1% or less. The solid content of the resin emulsion dispersion liquid is calculated by multiplying the mass of the resin emulsion dispersion liquid by the solid content concentration (%) of the resin emulsion dispersion liquid, and is a nonvolatile component measured in accordance with JIS K 6828-1. However, the drying temperature and time of the resin emulsion dispersion liquid were 105° C. and 3 hours. In addition, the mass of the filtration residue is the mass of the thing obtained by washing the filtration residue with water and drying it.

In a resin emulsion dispersion liquid having a viscosity of more than 100 mPa･s measured at a temperature of 30°C and a rotational speed of 30 rpm, dispersion may be difficult. The viscosity is preferably 50 mPa·s or less, more preferably 10 mPa·s or less, and more preferably 5 mPa·s or less.

The resin emulsion dispersion liquid preferably contains a water-soluble resin emulsion. In addition, the resin emulsion dispersion liquid may contain a water-soluble polymer in addition to the water-soluble resin emulsion.

The water-soluble resin emulsion is not particularly limited as long as it uses water as the dispersant and resin as the dispersoid. Various olefin-based compounds such as vinyl acetate, acrylate, styrene, ethylene, and butadiene can be used alone as main monomers. A water-soluble resin emulsion prepared by polymerizing or combining a plurality of them. Specifically, vinyl acetate resin emulsion, vinyl acetate copolymer emulsion, acrylate resin emulsion, styrene-acrylate copolymer emulsion, styrene-vinyl acetate copolymer emulsion (EVA emulsion), styrene- Butadiene copolymer emulsion, vinylidene resin emulsion, polybutene resin emulsion, acrylonitrile-butadiene resin emulsion, methacrylate-butadiene resin emulsion, asphalt emulsion, epoxy resin emulsion, polyurethane resin emulsion , Silicone resin emulsion, etc. Among them, resin emulsions containing structural units derived from vinyl acetate (vinyl acetate resin emulsions, vinyl acetate copolymer emulsions, ethylene-vinyl acetate copolymer emulsions, etc.) are preferred, and ethylene-vinyl acetate copolymer emulsions are more preferred .

When an ethylene-vinyl acetate copolymer emulsion is used as the water-soluble resin emulsion, the ethylene-vinyl acetate copolymer (EVA) contained in the ethylene-vinyl acetate copolymer emulsion has an ethylene monomer unit content of 5 to 35% by mass , the vinyl acetate monomer unit content is preferably 65 to 95 mass %. When there are too many ethylene monomer units, the film may become soft and the strength of the film may decrease. On the contrary, when the ethylene monomer unit is too small, the flexibility of the film may be lost, and it may be difficult to form a film in a cold region.

The production method of the water-soluble resin emulsion is not particularly limited, but for example, an emulsifier and a monomer are added to a dispersion medium containing water as a main component, and the monomer is produced by emulsion polymerization while stirring. As an emulsifier, an ionic (cationic, anionic, amphoteric) surfactant or a nonionic (Nonionic) surfactant is mentioned. Examples of the nonionic surfactant include low-molecular-weight surfactants such as alkyl glycosides, and high-molecular-weight surfactants such as polyvinyl alcohol, and high-molecular-weight surfactants are preferred. The polymer-based surfactant is particularly preferably a surfactant composed of polyvinyl alcohol, and the average degree of polymerization thereof is, for example, 200 to 2500, preferably 400 to 2200, and more preferably 500 to 2000. The larger the average degree of polymerization of polyvinyl alcohol, the higher its emulsifying and dispersing power. Therefore, in order to obtain an emulsion with a desired degree of dispersion, it is only necessary to use polyvinyl alcohol having an appropriate average degree of polymerization. In addition, a plurality of polyvinyl alcohols having different average degrees of polymerization may be used in combination. The degree of saponification of polyvinyl alcohol is not particularly limited, but is, for example, 70% or more, preferably 80 to 95%. The reason for this is that when the saponification is too low, the water solubility is extremely reduced, and it cannot be dissolved unless a special dissolution method is used, and it is difficult to use it in industry. The lower the degree of saponification of polyvinyl alcohol, the higher the emulsification and dispersing power. Therefore, in order to obtain an emulsion with a desired degree of dispersion, only polyvinyl alcohol having an appropriate degree of saponification may be used. A number of different emulsifiers can be used in combination. The addition amount of the emulsifier is not particularly limited, but is, for example, 2 to 10 parts by mass relative to 100 parts by mass of the input amount of the vinyl acetate monomer. The higher the amount of emulsifier added, the higher the emulsifying and dispersing power. Therefore, in order to obtain an emulsion with a desired degree of dispersion, the amount of emulsifier added can be appropriately adjusted.

In one form, the manufacturing method of the resin emulsion dispersion liquid includes the ethylene-vinyl acetate copolymer emulsion manufacturing process. In the ethylene-vinyl acetate copolymer emulsion production step, polyvinyl alcohol was added with respect to 100 parts by mass of the input amount of the vinyl acetate monomer.

The water-soluble polymer is not particularly limited, and examples thereof include methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxybutyl methyl cellulose, hydroxyethyl cellulose, and carboxymethyl cellulose. cellulose, aminomethyl hydroxypropyl cellulose, aminoethyl hydroxypropyl cellulose and other cellulose derivatives; starch, carrageenan, mannan, agarose, dextran, tragacanth, fruit Glue, animal glue, alginic acid or its salt; gelatin; polyvinylpyrrolidone; polyacrylic acid or its salt, polymethacrylic acid or its salt; acrylamides such as polyacrylamide and polymethacrylamide; hyaluronic acid and Its salts, chondroitin sulfate and its salts, polyvinyl alcohol, polyethyleneimine, polyethylene oxide, polyethylene glycol, polypropylene glycol, and glycerin may be used in combination. In addition, nonionic surfactants mixed with water can also be used, and examples thereof include polyoxyethylene nonylphenyl ether, polyoxyethylene styrenated phenyl ether, oxyethylene oleyl ether, and polyoxyethylene lauryl ether. Oxyethylene alkyl aryl ethers or polyoxyethylene alkyl ethers, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol monooleate and other polyoxyethylene fatty acid esters class, ethylene oxide/propylene oxide block copolymer, etc.

The method of spreading the resin emulsion dispersion liquid of the present invention on the soil is not particularly limited. For example, when spreading on a small area, a watering can or a power spreader can be used, and when spreading on a large area, a sprayer or a nozzle sprayer can be used. In addition, the dispersed resin emulsion dispersion liquid plays a role of forming a consolidated layer composed of the powder particles of the powdery sediment and the resin emulsion dispersion liquid, and at the same time, by maintaining the rainwater flowing into the consolidated layer, the inflow of rainwater existing in the consolidation layer is reduced. The amount of water in the powdery sediment under the layer has the effect of preventing the collapse of the powdery sediment and soil loss. In addition, the formation of the consolidation layer has an effect of preventing the generation of dust.

In addition, the resin emulsion dispersion liquid can be sprayed on the surface to be protected alone, or it can be mixed with a spray material containing soil as the main body and mixed with seeds, bark or fertilizer, etc., and sprayed on the surface to be protected together with the spray material. The method of spraying the spraying material on the corresponding surface is not particularly limited, and examples include seed spreading method, soil spraying method, substrate spraying method, etc., or when the target surface is wide, it can also be sprayed by aircraft such as helicopters.

The evaluation method of the resin emulsion dispersion liquid which concerns on one Embodiment of this invention has a viscosity measurement process, a mechanical stability calculation process, and a determination process. In the viscosity measurement step, the viscosity of the resin emulsion dispersion liquid is measured. In the mechanical stability calculation step, the mass of the filtration residue is measured by filtering the resin emulsion dispersion liquid after the load test to calculate the mechanical stability. In the determining step, it is determined whether the viscosity and the quality of the filtering residue are respectively within predetermined ranges.

The viscosity measurement in the viscosity measurement step is a viscosity measurement performed under predetermined measurement conditions (type of viscometer, temperature, rotation speed, etc.), and can be evaluated by various viscosity measurement methods. The viscosity measurement method can be measured using a B-type rotational viscometer, for example. A typical example of the viscosity measurement method is measurement using a B-type rotational viscometer at a temperature of 30° C. and a rotational speed of 30 rpm.

The load test in the mechanical stability calculation step is a load carried out under predetermined load conditions (temperature, load, rotation speed, test time, etc.), and can be carried out by various load methods. A typical example of the load condition is a condition of 5 minutes at 1000 rpm under a load of 10 kg at 20°C. In the measurement of the mass of the filtration residue, the resin emulsion dispersion liquid after the load test was filtered using filters such as various filter papers and filter screens, and the mass of the residue remaining on the filter was measured. More specifically, the resin emulsion dispersion was subjected to a test of 5 minutes at 20° C. under a load of 10 kg and 1000 rpm through a MARON type mechanical stability measuring device, and then filtered with a 100-mesh stainless steel wire mesh and filtered by the above formula (1). ) to calculate the mechanical stability.

An example of the determination step is to determine whether the viscosity measured with a B-type rotational viscometer at a temperature of 30°C and a rotational speed of 30 rpm is within a predetermined range, for example, whether it is 100 mPa･s or less, 50 mPa･s or less, or 10 mPa･s or less. or 5mPa･s or less. In addition, it is determined whether the mechanical stability calculated according to the above formula (1) is within a predetermined range, for example, whether it is 1.0 or not, when a load test is carried out at 1000 rpm for 5 minutes under a load of 20° C. and 10 kg, and filtered with a 100-mesh stainless steel wire mesh. % or less or 0.8% or less or 0.1% or less. When both the viscosity and the quality of the filtration residue are within the predetermined ranges, it can be evaluated that the dispersion liquid is easy to be dispersed using a dispersion device and that the nozzle of the dispersion device is not easily clogged during dispersion. [Example]

Examples of the present invention will be described below. Unless otherwise specified in the following explanations, "part", "%", and "ratio" mean "part by mass", "% by mass", "ratio by mass", respectively. In addition, the following are examples, and the content of the present invention is not limited thereto.

(Preparation of resin emulsion dispersion liquid) (Example 1) Into a high-pressure polymerization tank with a stirrer, a solution in which the following components were dissolved in 100 parts by mass of pure water in advance: polyvinyl alcohol (DENKA POVAL B-17 (degree of saponification 88 mol%, average degree of polymerization 1700, DENKA POVAL B-17 (degree of saponification 88 mol%, average degree of polymerization 1700, DENKA Co., Ltd.) 2.2 parts by mass; as auxiliary agents, 0.1 parts by mass of formamidine sulfinic acid, 0.2 parts by mass of sodium acetate, 0.005 parts by mass of ferrous sulfate heptahydrate, and 0.01 parts by mass of tetrasodium EDTA, and thereafter, Fill 73 mass parts of vinyl acetate monomers and 20 mass parts of ethylene under stirring, after making the internal liquid temperature be 55 ℃, add the ammonium persulfate aqueous solution continuously and carry out polymerization.When the polymerization rate reaches 60%, it lasts for 2 hours and 30 minutes in batches 35 parts by mass of vinyl acetate monomer was added. At the end of the polymerization, an aqueous solution of tert-butyl hydroperoxide was added, and the polymerization was continued until the amount of unreacted vinyl acetate monomer was less than 2 mass %. The ethylene remaining after the polymerization was removed, and the unreacted vinyl acetate monomer in the resulting emulsion was removed under reduced pressure. As a result, a resin emulsion having an unreacted vinyl acetate monomer of 0.5 mass % or less was obtained. The obtained resin emulsion was diluted with water to obtain a resin emulsion dispersion liquid having a solid content concentration of 7.0 wt %.

(Example 2) Into a high-pressure polymerization tank with a stirrer, a solution in which the following components were dissolved in 100 parts by mass of pure water in advance: polyvinyl alcohol (DENKA POVALB-05 (degree of saponification 88 mol%, average degree of polymerization 600, DENKA Co., Ltd.) as an emulsifier was put into Co., Ltd.) 4.7 parts by mass and DENKA POVALB-17 (degree of saponification 88 mol%, average degree of polymerization 1700, manufactured by DENKA Co., Ltd.) 1.2 parts by mass); as auxiliary agents, formamidine sulfinic acid 0.06 mass parts, sodium acetate 0.2 mass parts , 0.005 parts by mass of ferrous sulfate heptahydrate, 0.01 part by mass of tetrasodium ethylenediaminetetraacetate, and then, 89 parts by mass of vinyl acetate monomer and 20 parts by mass of ethylene were filled with stirring, and the temperature of the inner liquid was 55°C. , continuous addition of ammonium persulfate aqueous solution to carry out polymerization. When the pressure in the high-pressure polymerization tank decreased to 4.3 MPa, 28 parts by mass of vinyl acetate monomer was added in batches over 2 hours and 30 minutes. At the end of the polymerization, an aqueous solution of tert-butyl hydroperoxide was added, and the polymerization was continued until the amount of unreacted vinyl acetate monomer was less than 2% by mass. The ethylene remaining after the polymerization was removed, and the unreacted vinyl acetate monomer in the resulting emulsion was removed under reduced pressure. As a result, a resin emulsion having an unreacted vinyl acetate monomer of 0.5 mass % or less was obtained. The obtained resin emulsion was diluted with water to obtain a resin emulsion dispersion liquid having a solid content concentration of 7.0 wt %.

(Example 3) The same reaction as in Example 2 was performed, and the obtained resin emulsion was diluted with water to obtain a resin emulsion dispersion liquid having a solid content concentration of 30.0 wt %.

(Comparative Example 1) Into a high-pressure polymerization tank with a stirrer, a solution in which the following components were dissolved in 100 parts by mass of pure water in advance: polyvinyl alcohol (DENKA POVAL B-05 (degree of saponification 88 mol%, average degree of polymerization 600, DENKA POVAL B-05 (degree of saponification 88 mol%, average degree of polymerization 600, DENKA Co., Ltd.) 1.6 parts by mass; as auxiliary agents, 0.1 parts by mass of formamidine sulfinic acid, 0.2 parts by mass of sodium acetate, 0.005 parts by mass of ferrous sulfate heptahydrate, and 0.01 parts by mass of tetrasodium EDTA, and thereafter, Fill 73 mass parts of vinyl acetate monomers and 20 mass parts of ethylene under stirring, after making the internal liquid temperature be 55 ℃, add the ammonium persulfate aqueous solution continuously and carry out polymerization.When the polymerization rate reaches 60%, it lasts for 2 hours and 30 minutes in batches 35 parts by mass of vinyl acetate monomer was added. At the end of the polymerization, an aqueous solution of tert-butyl hydroperoxide was added, and the polymerization was continued until the amount of unreacted vinyl acetate monomer was less than 2 mass %. The ethylene remaining after the polymerization was removed, and the unreacted vinyl acetate monomer in the resulting emulsion was removed under reduced pressure. As a result, a resin emulsion having an unreacted vinyl acetate monomer of 0.5 mass % or less was obtained. The obtained resin emulsion was diluted with water to obtain a resin emulsion dispersion liquid having a solid content concentration of 7.0 wt %.

(Comparative Example 2) The same reaction as in Example 2 was carried out, and the obtained resin emulsion was diluted with water to obtain a resin emulsion dispersion liquid having a solid content concentration of 50.0 wt %.

(Comparative Example 3) The same reaction as in Comparative Example 1 was performed, and an aqueous polyvinyl alcohol solution was added to the obtained resin emulsion until the addition amount of polyvinyl alcohol (DENKA POVALB-05 (degree of saponification 88 mol%, average degree of polymerization 600, manufactured by DENKA Co., Ltd.) became 1.5 mass parts to obtain a resin emulsion dispersion liquid with a solid content concentration of 7.0 wt %.

(Comparative Example 4) Into a high-pressure polymerization tank with a stirrer, a solution in which the following components were dissolved in 100 parts by mass of pure water in advance: polyvinyl alcohol (DENKA POVAL B-17 (degree of saponification 88 mol%, average degree of polymerization 1700, DENKA POVAL B-17 (degree of saponification 88 mol%, average degree of polymerization 1700, DENKA Co., Ltd.) 1.6 parts by mass; as auxiliary agents, 0.1 parts by mass of formamidine sulfinic acid, 0.2 parts by mass of sodium acetate, 0.005 parts by mass of ferrous sulfate heptahydrate, and 0.01 parts by mass of tetrasodium EDTA, and thereafter, Fill 73 mass parts of vinyl acetate monomers and 20 mass parts of ethylene under stirring, after making the internal liquid temperature be 55 ℃, add the ammonium persulfate aqueous solution continuously and carry out polymerization.When the polymerization rate reaches 60%, it lasts for 2 hours and 30 minutes in batches 35 parts by mass of vinyl acetate monomer was added. At the end of the polymerization, an aqueous solution of tert-butyl hydroperoxide was added, and the polymerization was continued until the amount of unreacted vinyl acetate monomer was less than 2 mass %. The ethylene remaining after the polymerization was removed, and the unreacted vinyl acetate monomer in the resulting emulsion was removed under reduced pressure. As a result, a resin emulsion having an unreacted vinyl acetate monomer of 0.5 mass % or less was obtained. A polyvinyl alcohol aqueous solution was added to the obtained resin emulsion until the addition amount of polyvinyl alcohol ((DENKA POVALB-17 (degree of saponification 88 mol%, average degree of polymerization 1700, manufactured by DENKA Co., Ltd.)) became 1.5 parts by mass, and the solid content concentration was obtained as 1.5 parts by mass. 7.0 wt% resin emulsion dispersion.

(solid content) The solid content of the resin emulsion dispersion liquid was measured according to JIS K 6828 under drying conditions of 105° C. and 3 hours.

(viscosity) The viscosity of the resin emulsion dispersion liquid was measured under conditions of a temperature of 30° C. and a rotation speed of 30 rpm (measuring apparatus: Toki Sangyo TVB-33L-type viscometer).

(mechanical stability) After filtering the resin emulsion dispersion liquid with a 100-mesh stainless steel wire mesh, 50 g of the filtrate was collected, and the test was carried out at 1000 rpm for 5 minutes with a MARON type mechanical stability measuring device under a load of 20°C and 10 kgf, and a 100-mesh stainless steel wire mesh was used. After filtration, the filtration residue was washed with water, dried at 105° C. for 1 hour, and then cooled in a desiccator, and the mass was measured. The mechanical stability is calculated by the following formula. Mechanical stability (%) = filtration residue (g) / (50 (g) × resin emulsion dispersion liquid solid content concentration (%)) × 100

(spread) The temperature of the resin emulsion dispersion liquid was set to 25°C, and a spray nozzle (ECO SHOWER NOZZLE B10) manufactured by Maruyama Corporation was installed in a power sprayer (MS-252C) of Kosei Co., Ltd., and the discharge rate was 1.2 L/min. Spread it down below and check if it can be spread. In addition, the spraying was continued for 1 hour, and it was confirmed whether or not the nozzle clogging occurred during the spraying.

Examples, comparative examples, and evaluation results are shown in Table 1. In addition, the addition amount of each PVA in Table 1 is a conversion value when the input amount of vinyl acetate monomer is 100 mass parts.

[Table 1]

Claims (8)

A resin emulsion dispersion liquid, wherein, The viscosity measured at a temperature of 30°C and a rotation speed of 30rpm is 100mPa･s or less, After the test was carried out at 1000 rpm for 5 minutes at 20°C and a load of 10 kg by a MARON type mechanical stability measuring device, it was filtered through a 100-mesh stainless steel wire mesh. The mechanical stability calculated by the following formula is 1.0% or less: Mechanical stability (%)=filtration residue (g)/solid content of resin emulsion dispersion liquid (g)×100. The resin emulsion dispersion liquid according to claim 1, which comprises a water-soluble resin emulsion. The resin emulsion dispersion liquid according to claim 2, wherein, The water-soluble resin emulsion is an emulsion of a resin containing a structural unit derived from vinyl acetate. The resin emulsion dispersion liquid according to claim 2 or claim 3, wherein, The water-soluble resin emulsion is an emulsion containing ethylene-vinyl acetate copolymer. The resin emulsion dispersion liquid according to any one of claims 1 to 3, wherein, It is used as a dispersion liquid for dust prevention. The resin emulsion dispersion liquid according to any one of claims 1 to 3, wherein, Use as a spreading fluid to prevent soil loss. A method for producing a resin emulsion dispersion liquid, comprising a step of producing an ethylene-vinyl acetate copolymer emulsion. 2~10 parts by mass of emulsifier, After the test was carried out at 1000 rpm for 5 minutes at 20°C and a load of 10 kg by a MARON type mechanical stability measuring device, it was filtered through a 100-mesh stainless steel wire mesh. The mechanical stability calculated from the following formula is 1.0% or less, and the viscosity measured at a temperature of 30°C and a rotation speed of 30rpm is 100mPa･s or less: Mechanical stability (%)=filtration residue (g)/solid content of resin emulsion dispersion liquid (g)×100. A method for evaluating a resin emulsion dispersion liquid, comprising a viscosity measurement step, a mechanical stability calculation step, and a determination step, wherein, In the viscosity determination step, the viscosity of the resin emulsion dispersion liquid is measured, In this mechanical stability calculation step, the resin emulsion dispersion liquid is subjected to a test at 20° C. under a load of 10 kg at 1000 rpm for 5 minutes through a MARON mechanical stability measuring device, and then filtered with a 100-mesh stainless steel wire mesh from the following Calculate the mechanical stability using the formula: Mechanical stability (%) = filtration residue (g)/solid content of resin emulsion dispersion liquid (g) × 100 In this determination step, it is determined whether the viscosity is 100 mPa·s or less, and whether the mechanical stability is 1.0% or less.