JPH01110506A - Production of aqueous resin dispersion - Google Patents

Abstract

PURPOSE:To obtain an aqueous resin dispersion useful as an ink, paper processing agent, etc., by carrying out radical polymerization of a monomer having polymerizable unsaturated bond in the presence of a urethane emulsion having a specific average particle diameter. CONSTITUTION:An aqueous resin dispersion having a moderate rate of polymerization, low frothing tendency, high surface tension and excellent water-resistance can be produced by the radical polymerization of 97-99.8wt.% of a monomer having polymerizable unsaturated bond (e.g., acrylic acid, hydroxyethyl acrylate or acrylonitrile) in the presence of 0.2-3wt.% of one or more urethane emulsions having an average particle diameter of 0.001-0.035mum and preferably in the presence of a polymerization catalyst such as potassium persulfate or di-tert-butyl hydroperoxide.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing an aqueous resin dispersion, and more specifically, it relates to a method for producing an aqueous resin dispersion, and more specifically, a method for producing an aqueous resin dispersion, which has an appropriate polymerization rate, low foaming, and high surface tension. The present invention relates to a method for producing an aqueous resin dispersion having excellent water resistance.

[Conventional technology and its problems]

Emulsions, which are so-called emulsions of various polymeric substances, use water as a solvent, so they are safer for the environment and the human body than solvent-based products, and are used in paints, textile processing agents, adhesives, and paper. It is currently widely used as a processing agent.

In the production of emulsions, providing a place for polymerization,
In order to stabilize the produced emulsion, anionic surfactants such as alkylbenzene sulfonates, alkyldiphenyl ether disulfonates, alkyl sulfate salts, higher fatty acid salts, and nonionic surfactants such as polyoxyethylene alkylphenyl ethers are generally used. are used singly or as a mixture in an amount of 0.5 to 5% by weight based on the raw material monomers.

However, emulsions produced using these surfactants have high foaming properties and low surface tension.
Several problems have arisen in manufacturing or in use, including:

Namely, (1) Due to the high foaming property, the amount charged during emulsion production is large, making observation of the reaction state insufficient. ■When painting emulsion, bubbles cause pinholes. ■If the surface tension is low, the adhesive strength tends to be weak when emulsions are used as adhesives, and when used as fiber processing agents, the permeability of emulsions into fibers is too high and the characteristics of the fibers themselves cannot be utilized. become less likely to be Furthermore, since the surfactant is non-volatile, it remains in the film prepared from the emulsion and improves the water resistance of the film.
It has also been pointed out that it causes a decrease in adhesion, tensile strength, heat resistance, weather resistance, etc.

Various methods have been studied to improve the adverse effects caused by these surfactants, such as so-called reactive surfactants with ethylenically unsaturated bonds in their molecular weight, maleic acid adducts of liquid polybutadiene, and alkylmercapto groups at the ends. A method using a polymer type surfactant such as an acrylic acid-acrylonitrile copolymer, and an emulsion polymerization method in the absence of an active agent are known.

However, in methods using these reactive or polymeric surfactants, the structures of these surfactants are complicated in terms of providing a polymerization site, which is the basic performance required of surfactants in emulsion polymerization. Therefore, the ability to form micelles is suppressed and the rate of emulsion polymerization decreases. Therefore, in order to obtain an appropriate polymerization rate, it is necessary to add a large amount of activator. Therefore, even if it is possible to obtain an emulsion with low foaming properties and high surface tension by using these activators, it is not possible to sufficiently improve the decrease in polymerization rate and the decrease in water resistance of the film.

Furthermore, the details of the polymerization method for emulsion polymerization in the absence of an activator are described in many literatures, such as Yamazaki et al.'s "New Developments and Problems of Synthetic Polymer Latex" [Chemical Industry Materials (Tokyo Technological Examination News) vol. 13(4) P3(
197B)), the aqueous resin dispersion obtained by emulsion polymerization in the absence of an activator has a problem of extremely poor storage stability and mechanical stability, and is not practical.

On the other hand, a method is known in which a monomer having a polymerizable unsaturated bond is radically polymerized in the presence of a gel-like aqueous polyurethane dispersion or in the presence of an oligourethane salt. Generally, when a gel-like polyurethane dispersion has a strong crosslinking bond, the water silica dispersion becomes very unstable and cannot undergo radical emulsion polymerization in the presence of such an unstable gel-like aqueous dispersion. The resulting resin emulsion or latex also becomes extremely unstable.

Moreover, oligourethane salts are linear oligomers with a low molecular weight of about 1,500 to 20,000, and if the tensile strength of the resin is about 20 kg/cm" or less, such a low molecular weight causes poor mechanical properties. Oligourethane salts have a very strong negative effect on the physical properties of the dry film of the resin emulsion obtained by radical emulsion polymerization in the presence of oligourethane salts with specific properties, making it impossible to obtain resin emulsions or latexes with excellent physical properties. Ta.

[Means for Solving the Problems] The present inventors have developed an aqueous resin dispersion that has an appropriate polymerization rate under such actual conditions, has no foaming property in the obtained emulsion, has a high surface tension, and has good water resistance. As a result of intensive research on the production method for obtaining the product, it was discovered that it is extremely effective to radically polymerize a monomer having a polymerizable unsaturated bond in the presence of a urethane emulsion with a particle size of 0.001 to 0.035μ, The present invention has now been completed.

That is, in the present invention, the average particle diameter is 0.001μ to 0.035μ.
In the presence of one or more urethane emulsions of 0.2% to less than 3% by weight (solid content), 99.8 to 97% by weight of monomers having polymerizable unsaturated bonds are radicalized. The present invention relates to a method for producing an aqueous resin dispersion, which is characterized by polymerization, and has low foaming, high surface tension, and excellent water resistance.

The reason why an aqueous resin dispersion having the above properties can be obtained by radical polymerizing a monomer having a polymerizable unsaturated bond in the presence of the urethane emulsion having the above particle size used in the present invention is as follows. It is possible that

In other words, one of the major reasons why ordinary surfactants are used in emulsion polymerization is that surfactants form micelles with an ultrafine particle size (~100 particles) in water, and monomers are contained in these micelles. In addition to being solubilized, the micelles have a very large total surface area due to their ultra-fine particle size, and can efficiently capture initiator radicals generated in water due to thermal decomposition of the initiator, facilitating smooth polymerization. It lies in what can be done.

Therefore, horsetail/tan emulsion having a particle size equivalent to that of micelles is considered to have similar performance. Moreover, if such a polymer emulsion can be produced under conditions that minimize activator incompatibility, an aqueous resin dispersion with an appropriate polymerization rate, no foaming, high surface tension, and excellent water resistance can be produced. You should be able to get it.

The urethane emulsion used in the present invention can be manufactured by various methods, and a typical manufacturing method is, for example, as follows.

■ Polymerization products such as tetrahydrofuran, propylene oxide, and ethylene oxide, polyethers that are copolymerization products,
Dehydration condensation reaction between polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, and hexanediol and polyhydric carboxylic acids such as maleic acid, succinic acid, adipic acid, and phthalic acid, or ring-opening polymerization reaction of cyclic esters. The resulting polyhydroxyl compound represented by polyester, polyacecool, polyester amide, hyphorithioether, etc., and aromatic polyisocyanate such as 1,5-naphthalene diisocyanate, 4,4'-diphenylmethane diisocyanate, phenylene diisocyanate, toluene diisocyanate, or Hexamethylene diamine □ Polyisocyanates represented by aliphatic diisocyanates such as anate, dicyclohexylmethane diisocyanate, and xylylene diisocyanate, as well as the above polyhydric alcohols and ethylene diamine, propylene diamine, diethylene triamine,
A urethane polymer solution is obtained by reacting a chain extender represented by low-molecular polyamines such as hexamethylene diamine and xylylene diamine in an inert organic solvent such as tetrahydrofuran, acetone, methyl ethyl ketone, ethyl acetate, and toluene. A method of obtaining water-based polyurethane by adding and mixing this in water containing an appropriate amount of emulsifier, and then distilling off the inert organic solvent.

■ A urethane prepolymer containing free isocyanate groups produced from a polyhydroxyl compound and excess polyisocyanate is chain-extended in water containing an active hydrogen compound such as low-molecular polyamines or polyhydric alcohol and an emulsifier. A method of obtaining water-based polyurethane by emulsification.

■ A method in which a urethane prepolymer containing free isocyanate groups is emulsified in water using tertiary amines as a catalyst, and chain-extended with water to obtain aqueous polyurethane.

■ A urethane prepolymer with terminal isocyanate groups containing a salt-forming compound such as N,N-dimethylethanolamine is dispersed in water containing a neutralizing agent and an emulsifier, and then low-molecular-weight polyamines are added to extend the chain to form a water-based polyurethane. How to get it.

■ A prepolymer with a terminal hydroxyl group obtained from a polyhydroxyl compound and a polyisocyanate, or a compound with a terminal amino group obtained by reacting a diamine with a urethane prepolymer with a terminal isocyanate group is emulsified in water using an emulsifier. After that, polyisocyanate is added to polymerize it to obtain water-based polyurethane.

■Urethane prepolymer with terminal isocyanate groups,
A method of obtaining an aqueous polyurethane by reacting a compound having a tertiary amino group such as N-alkyl jetanolamine or triethanolamine, then neutralizing it with an acid, and emulsifying it in water.

■Urethane prepolymer with terminal isocyanate groups,
A method of reacting a compound having a tertiary amino group such as N-alkylgetanolamine, quaternizing the tertiary amino group with an alkylating agent, and then mixing with water to obtain an aqueous polyurethane.

(2) A method in which a urethane polymer containing a halogen group or a sulfonic acid group is reacted with a tertiary amine and then mixed with water to obtain a water-based polyurethane.

■ React the hydroxyl groups or amino groups of polyurethane containing primary and/or tertiary hydroxyl groups and/or amino groups with a compound that produces a salt after ring opening, such as a cyclic dicarboxylic acid anhydride, sultones, or lactones. A method in which water-based polyurethane is obtained by neutralizing the polyurethane with a base and then mixing it with water.

[Phase] A method of obtaining an aqueous polyurethane by chain-extending a urethane prepolymer with terminal isocyanate groups produced from a water-soluble polyhydroxyl compound and a polyisocyanate in an aqueous solution of a polyfunctional amine.

■ A urethane prepolymer with a terminal isocyanate group is reacted with an aqueous solution of an alkali or ammonium salt of a diaminocarboxylic acid, such as a compound having an amino group or hydroxyl group and a sulfonic acid group or a carboxyl group, and emulsification is carried out at the same time as chain extension to obtain an aqueous polyurethane. Method.

@ A method to obtain aqueous polyurethane by reacting a polyhydroxyl compound, a compound having a quaternary ammonium group and a hydroxyl group in the molecule, a compound having an epoxy group and a hydroxyl group in the molecule, and a polyisocyanate and mixing it with water.

(2) A method in which a urethane prepolymer having terminal isocyanate groups is reacted with a hydroxyl compound having a quaternary ammonium base and mixed with water to obtain an aqueous polyurethane.

■ A method for obtaining water-based polyurethane by reacting polyoxyethylene glycol or a water-soluble glycol, which is a ring-opened copolymer of propylene oxide and ethylene oxide, with polyisocyanate.

■ A urethane prepolymer containing carboxyl groups and isocyanate groups manufactured from a polyhydroxyl compound having carboxyl groups and polyisocyanate is mixed with an aqueous solution of a basic substance, and at the same time it is neutralized and chain-extended with water or low-molecular polyamines to form an aqueous solution. How to get polyurethane.

■ A polyurethaneurea polyamine is produced by reacting a polyalkylene polyamine such as diethylene triamine with a urethane prepolymer having terminal isocyanate groups, and an aqueous acid solution is added to this, or an aqueous acid solution is added after epihalohydrin is added to the polyurethaneurea polyamine. How to obtain water-based polyurethane by adding

■ A method of obtaining an aqueous polyurethane by reacting the above-mentioned polyurethaneurea polyamine, its alkyl (C+□-C2□) isocyanate adduct, or its epihalohydrin adduct with a cyclic dicarboxylic acid anhydride, and then mixing with an aqueous solution of a basic substance. .

■ Reacting the above polyurethaneurea polyamine or its epihalohydrin adduct with sultones or lactones, or reacting monohalogenated sodium carboxylate, or reacting (meth)acrylic acid ester or acrylonitrile, and then hydrolyzing it; Then mixed with water to obtain water-based polyurethane.

■ A polyurethaneurea polyamine is produced by reacting a polyalkylene polyamine such as diethylene triamine with a urethane prepolymer with terminal isocyanate groups obtained from a polyhydroxyl compound containing polyoxyethylene glycol and a polyisocyanate, and this is mixed with water, or A method of adding epihalohydrin to the polyurethaneurea polyamine and then mixing it with water to obtain a water-based polyurethane.

In addition to the aqueous polyurethane produced by the method shown in the representative examples above, polyurethane that stably exists with a particle size of 0.001 .mu.m to 0.035 .mu.m can be effectively used in the present invention.

Among the above, aqueous polyurethanes obtained by the methods of [Phase] to (2) are particularly useful.

The urethane emulsion of the present invention having a particle size of 0.001 μm to 0.035 μm is a transparent or semitransparent colloidal dispersion, and Tyndall phenomenon is observed when irradiated with laser light. or,
Due to Rayleigh scattering, it appears blue-white in reflected light and yellow-red in transmitted light.

As the monomer having a polymerizable unsaturated bond used in the present invention, a radically polymerizable compound is used. α, β-unsaturated carboxylic acid amides such as amide, maleic acid amide, maleic acid imide, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, stearyl methacrylate, hydroxyethyl Acrylate, hydroxypropyl acrylate, 2-aminoethyl methacrylate hydrochloride, dimethylaminoethyl methacrylate, methoxymethyl methacrylate, chloromethyl methacrylate, dichlorotriazinyl aminoethyl methacrylate, and esters of maleic acid, fumaric acid, itaconic acid, etc., α,
Esters of β-unsaturated carboxylic acids, substituted amides of unsaturated carboxylic acids such as methylol acrylamide, methylol methacrylamide, methoxymethyl acrylamide, α, β- such as acrylonitrile, methacrylonitrile, etc.
In addition to unsaturated carboxylic acids such as nitrile, vinyl acetate, vinyl chloride, and vinyl chloroacetate, divinyl compounds, vinylidene compounds, aromatic vinyl compounds represented by styrene, and heterocyclic vinyl compounds represented by vinylpyridine and vinylpyrrolidone. Vinyl ketone compounds, vinyl ether compounds, vinylamide compounds, monoolefin compounds such as ethylene and propylene, conjugated diolefin compounds such as butadiene, isoprene and chloroprene, allyl compounds such as allyl alcohol and allyl acetate, and monoolefin compounds such as glycidyl methacrylate. One or more monomers selected from the group of monomers are used.

Particle size 0.001 to 0.035 produced by the above method
Polymerization catalysts used in the radical emulsion polymerization of the above-mentioned monomers having polymerizable unsaturated bonds in the presence of μ urethane emulsion include potassium persulfate, ammonium persulfate, hydrogen peroxide, peroxide benzoyl, t
-butyl hydroperoxide, succinic acid hydroperoxide, cumene hydroperoxide,
Peroxides such as p-methane hydroperoxide, di-tert-butyl hydroperoxide, and tert-butyl perbenzoic acid, or 2,2'-azobis(2-amidinopropane) hydrochloride, azobiscyclohexanecarbonitrile, etc. Preferred representative examples include azobis-based initiators such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, monoethanolamine, jetanolamine, triethanolamine, and propylene diamine. , water-soluble amines such as diethylamine, monoethylamine, pyrosulfite, sodium bisulfite; sodium formaldehyde sulfoxylate, etc. are used as activators in combination with polymerization catalysts, and as polymerization degree regulators, organic halogen compounds, nitro compounds,
Alkyl mercaptans, diisopropyl xanthic acid, etc. can also be used.

The emulsion polymerization reaction according to the present invention is performed using particles jMO according to the present invention.
In the presence of a urethane emulsion of 0.01μ to 0.035μ, the above-mentioned polymerizable monomers, catalysts, catalyst activators, polymerization regulators, etc. are suitably combined as appropriate, and a special device is applied by a known method. It will be implemented.

In addition, in the present invention, the particle size o, ootμ ~ 0.035
The mixing ratio of the urethane emulsion of μ and the polymerizable monomer is 99.8 to 97% by weight of the polymerizable monomer, and the particle size is 0.
．． 001μ~0.035μ urethane emulsion 0.
It is 2% by weight or more and less than 3% by weight (solid content).

If the amount of urethane emulsifier with a particle size of 0.001μ to 0.035μ is less than 0.2% by weight, it will be difficult to maintain an appropriate polymerization rate and emulsion dispersion stability, and if it is 3% by weight or more, the emulsification will be difficult. Although the dispersion stability increases, the amount of precursor material increases relatively, so the application performance of the emulsion polymer obtained is affected by the fact that the precursor material is a relatively low polymer and contains many hydrophilic groups. There will be an impact.

On the other hand, when a urethane emulsion with a particle size larger than 0.035 μm is used, it is difficult to obtain an appropriate polymerization rate, and a long time is required to complete the emulsion polymerization.

Furthermore, o, oo used in the emulsion polymerization reaction according to the present invention
Since the urethane emulsion with a tμ to 0.035μ functions as a surfactant itself, there is no need to use a protective colloid or a surfactant in the emulsion polymerization reaction, but the stability of the aqueous resin dispersion produced It goes without saying that conventionally known protective colloids and surfactants can be used in order to improve the properties of the resin as long as they do not adversely affect the physical properties of the resulting resin.

Furthermore, depending on the application in which the aqueous resin dispersion produced by the method of the present invention is used, commonly used antifoaming agents, antifungal agents, fragrances, fluorescent whitening agents, antioxidants, and ultraviolet absorbers may be added. ,
In addition to reinforcing agents, fillers, pigments, antistatic agents, anti-blocking agents, flame retardants, plasticizers, lubricants, organic solvents, tackifiers, thickeners, foaming agents, coloring agents, etc., epoxy-based crosslinking agents A compound, a compound having a methylol group or an alkoxymethyl group, a catalyst, etc. can be blended into the aqueous resin dispersion.

On the other hand, when the aqueous resin dispersion produced by the method of the present invention is used as a coating film, a dense coating film is obtained, and mechanical properties such as water resistance, gloss, adhesion, transparency, and tensile strength are improved. Are better.

The aqueous resin dispersion produced by the method of the present invention includes fiber materials, nonwoven fabrics, paper, leather, rubber, wood, metal, asphalt, concrete, plaster, ALC boards, ceramic siding materials, glass, glass fibers, and plastics. By impregnating or applying it to these surfaces and drying, it is possible to obtain performance improvement effects such as surface coating, adhesion, and texture improvement. It can be advantageously used in fields where coating agents for POS labels, civil engineering and construction, inks, paints, various binders, adhesives, paper processing agents, cement admixtures, and rubber latex and resin emulsions are commonly used. .

〔Example〕

Next, the present invention will be specifically explained with reference to reference examples and examples, but it goes without saying that the present invention is not limited thereto.

In addition, all parts and percentages in the examples are based on weight unless otherwise specified.

Reference example-1 Propylene oxide adduct of bisphenol A (hydroxyl value 2
60.4) 1916 parts, methyl ethyl ketone 1485
part and 2.4-1-lylene diisocyanate and 2゜6-
80720 Mixture of Drylene Diisocyanate 154
Place 8 parts in a round bottom flask fitted with a stirrer and thermometer,
After reacting for 4 hours at 5°C, a urethane prepolymer solution containing 7.55% free isocyanate groups was obtained.

Meanwhile, in another flask, 374 parts of methyl ethyl ketone, 12.3 parts of diethylenetriamine, 21.1 parts of N-methylaminopropylamine, and 15.5 parts of di-n-butylamine were added.
400 parts of the above-mentioned urethane prepolymer solution was gradually added to this while stirring from the dropping funnel over a period of 1 hour, and reacted at 50°C for 30 minutes to form a polyurethane. A urea polyamine solution was obtained.

An infrared absorption spectrum was measured using a drop of this solution, and it was determined that <225
No absorption at 0 cm-' was observed.

Subsequently, 24 parts of succinic anhydride dissolved in 120 parts of methyl ethyl ketone was added to this polyurethaneurea polyamine solution, and the mixture was reacted at 50"C for 30 minutes, and then 7.7
Dissolve 1 part of caustic soda in 900 parts of water and add
Methyl ethyl ketone was distilled off under reduced pressure at 50''C.

Next, water was added to adjust the concentration to obtain a uniform, stable, low-viscosity polyurethane emulsion with a resin content of 30%.

The obtained polyurethane emulsion is transparent and has a Tyndall phenomenon when irradiated with a laser beam, and has a particle size of 0.
It was 0.006μ.

In addition, the particle size is C011LTI! RI! LBCTRONI
Measurement was performed using COULTERMODHL N4 manufactured by C3INC.

Reference example-2 Reference example-1 except that the amount of caustic soda added is 5.8 parts
A polyurethane emulsion with a particle size of 0.01μ was obtained in the same manner as above.

Reference Example-3 382 parts of methyl ethyl ketone, 31.6 parts of N-methylaminopropylamine, and 23.2 parts of di-n-butylamine were placed in a flask and mixed uniformly, and the urethane prepolymer synthesized in Reference Example-1 was added to the mixture. 400 parts of the solution was gradually added over 1 hour through the dropping funnel with stirring, and the solution was heated at 50°C.
C for 30 minutes to obtain a polyurethaneurea polyamine solution.

An infrared absorption spectrum was measured using a drop of this solution, and it was determined that <225
No absorption at 0 cm-' was observed.

Subsequently, 17.9% was added to this polyurethaneurea polyamine solution.
Part of succinic anhydride dissolved in 90 parts of methyl ethyl ketone was added and reacted at 50°C for 30 minutes, then 7.
Dissolve 2 parts of caustic soda in 860 parts of water and add 40 parts of caustic soda.
Methyl ethyl ketone was distilled off under reduced pressure at ~50°C.

Next, water was added to adjust the concentration to obtain a uniform, stable, low-viscosity polyurethane emulsion with a resin content of 30%.

The obtained polyurethane emulsion is transparent and has a Tyndall phenomenon when irradiated with a laser beam, and has a particle size of 0.
It was 03μ.

Reference Example-4 A urethane prepolymer solution containing 7.74% of free isocyanate groups was obtained by reacting with the same ingredients as in Reference Example-1.

In a separate flask, add 386 parts of methyl ethyl ketone and 25,
3 parts of diethylenetriamine and 31.7 parts of dibutylamine were added and mixed uniformly, and 400 parts of the above urethane prepolymer solution was gradually added to this while stirring from the dropping funnel over a period of 1 hour. A polyurethaneurea polyamine solution was obtained by reacting at °C for 30 minutes.

An infrared absorption spectrum was measured using a drop of this solution, and it was determined that <225
No absorption at 0 cm-' was observed.

Subsequently, 24.6 was added to this polyurethaneurea polyamine solution.
1 part of succinic anhydride dissolved in 125 parts of methyl ethyl ketone was added, reacted at 50°C for 30 minutes, and then
．． Add 4 parts of caustic soda dissolved in 910 parts of water,
Methyl ethyl ketone was distilled off under pressure at 0 to 50°C.

Next, water was added to adjust the concentration to obtain a uniform, stable, low-viscosity polyurethane emulsion with a resin content of 30%.

The obtained polyurethane emulsion was cloudy and had a particle size of 0.
．． It was 04μ.

Reference Example 5 A urethane emulsion having a particle size of 0.06 μm was obtained in the same manner as Reference Example 4 except that 4.5 parts of caustic soda was used.

Examples-1 to 3 The amount of the urethane emulsion obtained in Reference Example-1 listed in Table 1 was placed in a reactor equipped with a nitrogen inlet tube, a stirrer, and a thermometer, and 500 parts of ion-exchanged water and styrene/butyl acrylate were added. ) = 1/1 mixture was added thereto, and the atmosphere was replaced with nitrogen at room temperature. Next, the liquid temperature was adjusted to 30°C, 5 parts of a 2% aqueous potassium persulfate solution was added, and the reactor was immersed in an 80°C oil bath to initiate polymerization.

After a certain period of time, a portion of the reaction solution was sampled and its solid content was measured (drying at 150°C for 3 hours) to determine the polymerization rate. After further polymerization for 2 hours, the surface tension, foaming, and water resistance of the dried film of the obtained emulsion were measured by the methods shown below.

The above results are summarized in Table 1.

Surface tension〉 CBVP 5surface tensio manufactured by Kyowa Chemical
Measured at room temperature using nmeter3A.

<Foaming> Emulsion 10-relative was placed in a 30-relative test tube, vigorously shaken for 30 seconds, the total volume including foam was measured, and the volume increase was expressed in %.

<Water Resistance> The emulsion was applied on a glass plate and dried overnight at 70°C. The resulting coating was submerged in tap water for one day, and the degree of whitening and blistering was visually judged according to the following criteria. .

Examples 4 and 5 Polymerization was carried out in the same manner as in Example 1 except that 2 parts of the urethane emulsion obtained in Reference Examples 2 and 3 was used instead of the urethane emulsion obtained in Reference Example 1. The polymerization rate, surface tension of the obtained emulsion, foaming, and water resistance of the dried film were evaluated in the same manner as in Example-1.

The results are summarized in Table 1.

Comparative Example-1 Polymerization was carried out in the same manner as in Example-1 except that 0.1 part of the urethane emulsion obtained in Reference Example-1 was used. Surface tension, foaming, and water resistance of the dried film were evaluated.

The results are shown in Table 1.

Comparative Examples 2 and 3 Polymerization was carried out in the same manner as in Example 1, except that 2 parts of the urethane emulsions obtained in Reference Examples 4 and 5 were each used instead of the urethane emulsion obtained in Reference Example 1. The polymerization rate, surface tension and foaming of the obtained emulsion, and water resistance of the dried film were evaluated in the same manner as in Example-1.

The results are summarized in Table 1.

Comparative Example-4 The same method as in Example-1 was used except that 2 parts of a surfactant and alkyldiphenyl ether disulfonate (Perex 5S-L manufactured by Kao ■) were used instead of the urethane emulsion obtained in Reference Example-1. Polymerization was carried out, and the polymerization rate, surface tension and foaming of the obtained emulsion, and water resistance of the dried film were evaluated in the same manner as in Example-1.

The results are shown in Table 1.

Claims (1)

[Claims] A monomer having a polymerizable unsaturated bond in the presence of 0.2% by weight or more and less than 3% by weight (solid content) of one or more types of urethane emulsion having an average particle size of 0.001μ to 0.035μ A method for producing an aqueous resin dispersion, which comprises radically polymerizing 99.8 to 97% by weight of the dispersion.