JPS6037801B2 - Method for producing vinyl resin water dispersion for coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an aqueous vinyl resin dispersion for coating that exhibits excellent storage stability even when an organic solvent is added.

Conventionally, methods for producing vinyl resin aqueous dispersions for coating have been disclosed, for example, in Tokukan Sho 51-7033 or No. 48-6018.
It is known to polymerize ethylenically unsaturated monomers in water using the carboxy-functional copolymers disclosed in No. 1 as emulsion stabilizers.

However, when the aqueous resin dispersion obtained by this method is made into a paint, adding an organic solvent to adjust coating workability tends to cause thickening, aggregation, precipitation, etc., which is a very serious problem in practice. The present inventors have carried out extensive research in order to provide a method for producing an aqueous vinyl resin dispersion for coating without such problems, and as a result, as an emulsion stabilizer of the above conventional method, a general formula, [in the formula, R and R2 are the same or different and are a hydrogen atom or a methyl group, R3 is a hydrogen atom or C, ~
3 alkyl group, and n represents 2-20.

], b is an ethylenically unsaturated carboxylic acid, and c is another ethylenically unsaturated monomer obtained by the polymerization of an ethylenically unsaturated monomer having the formula [in the formula,
R,, R2, R3 and n have the same meanings as above.

] It has been discovered that the desired resin aqueous dispersion can be obtained by using a neutralized vinyl copolymer having a specific ratio of units represented by the formula and having a specific acid value. The present invention was completed based on this knowledge, and its gist is that the above ethylenically unsaturated monomer a, ethylenically unsaturated carboxylic acid b and other ethylenically unsaturated monomer c are polymerized. The obtained 9' vinyl copolymer having 5 to 40% (wt%, same hereinafter) of units represented by the above formula [B] in the molecule and having an acid value of 30 to 200 KOH is in a neutralized state. The present invention relates to a method for producing an aqueous vinyl resin dispersion for coating, which comprises polymerizing an ethylenically unsaturated monomer in an aqueous medium.

The vinyl copolymer of the present invention has 5 to 40%, preferably 10 to 30%, of the above units in the molecule, and has an acid value of 30 to 200 KOH, preferably 35 to 30.
It is important that it is set in the 9/evening range of 150KOH.

If the ratio of the above units is less than 5%, the storage stability of the target resin aqueous dispersion due to the addition of an organic solvent will be impaired.
Moreover, if it exceeds 40%, water resistance will deteriorate. As mentioned above, if the self-acid value is less than 9/Shi of 30KOH, even if the vinyl copolymer is neutralized and used as an emulsion stabilizer, its emulsifying or dispersing function will be insufficient, and the target resin aqueous dispersion will be If it cannot be obtained in a stable state, and if it exceeds 200 KOH yield/unit, it will adversely affect the physical properties of the target resin aqueous dispersion, especially the water resistance and corrosion resistance, and is not practical. The above-mentioned pinyl copolymer used in the present invention contains 5 to 40% ethylenically unsaturated monomer, and the vinyl copolymer has an acid value of 30%.
It is obtained by solution polymerizing an ethylenically unsaturated carboxylic acid (b) and other ethylenically unsaturated monomer (c) blended to have a concentration of ~200 KOH/h by a conventional method.

Examples of the ethylenically unsaturated monomer a include polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, methoxypolyethylene glycol monoacrylate, methoxypolyethylene glycol monomethacrylate, etc. It may be used as a seed or a mixture of two or more types.

The ethylenically unsaturated carboxylic acid b includes all substances that simultaneously have one ethylenically unsaturated group and one or more carboxyl groups in the molecule, and specific examples include:
Acrylic acid, methacrylic acid, crotonic acid, maleic acid,
Examples include fumaric acid, itaconic acid, monooctyl maleate, monobutyl maleate, monooctyl itaconate, and reaction products obtained by adding 2-hydroxyethyl methacrylate and phthalic anhydride in a molar ratio of 1:1. One or a mixture of two or more of these may be used.

As the other ethylenically unsaturated monomer c, one or a mixture of two or more selected from the following groups may be used.

M Esters of acrylic acid or methacrylic acid and C, ~, 8 monoalcohols (e.g. ethyl acrylate, n-butyl acrylate, i-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, n-butyl methacrylate, methacrylate) (i-butyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, etc.)

Such monomers are used to maintain good gloss, transparency, mechanical properties, chemical resistance, weather resistance, stripability, etc. of the coating, and the amount used is 30% or more of the total monomers. It is sufficient to select within the range of . (o' hydroxyl group-containing ethylenically unsaturated monomers (e.g. 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 1-methyl-2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, methacrylate) 1-methyl-hydroxyethyl acid, polypropylene glycol monomethacrylate, glycerol monomethacrylate, 3-chloro2 methacrylate
- hydroxypropyl, allyl alcohol, etc.).

Such monomers contribute to the stabilizing effect of the emulsion stabilizer, but when a curing agent is added to the target resin aqueous dispersion and it is desired to obtain a crosslinked film, monomers a and b alone do not have sufficient crosslink density. It is used in appropriate amounts to compensate for insufficient amounts. (1) Alkenyl aromatic monomers (eg, styrene, Q-methylstyrene, chlorostyrene, vinyltoluene, paratertiary butylstyrene, etc.).

Such monomers improve the gloss and transparency of the coating, but it is desirable to use them in an amount of 40% or less of the total monomers. 40%
If it exceeds this, the weather resistance of the film will deteriorate. 9 Amides of ethylenically unsaturated carboxylic acids and their substituted amides (e.g. acrylic acid amide, methacrylic acid amide, maleic acid amide, N-methylolacrylamide, N-butoxymethylacrylamide, diacetone acrylamide,
hydroxymethyl diacetone acrylamide, etc.).

Such a monomer can make the target resin aqueous dispersion self-crosslinking, and the amount used may be selected within a range of 30% or less based on the total monomers. {vs. Nitriles of ethylenically unsaturated carboxylic acids (e.g. acrylonitrile, methacrylonitrile, etc.). N Ethylenically unsaturated dicarboxylic acid gester (eg diptyl maleate, etc.).

(An addition reaction product between glycidyl acrylate or glycidyl methacrylate and fatty acids.

An addition reaction product of acrylic acid or methacrylic acid and epoxy resin (trade name: "Cardura E" manufactured by Shell).

[Li} Blocked isocyanate group-containing ethylenically unsaturated monomer (for example, diisocyanate such as tolylene diisocyanate, isophorone diisocyanate, etc.). One isocyanate group is blocked with a blocking agent such as lactam or oxime, and the other is methacrylic acid 2- to the isocyanate group of
Compounds to which ethylenically unsaturated monomers containing active hydrogen groups such as hydroxyethyl are added).

Such monomers also have the same functions as the superconducting monomers,
It may be used in an amount of 30% or less of the total monomers. Meat Ethylenically unsaturated monomers containing phosphate or sulfonic acid groups (e.g. acid phosphooxyethyl methacrylate,
3-chloro 2-acid phosphooxypropyl methacrylate, ethyl sulfonate methacrylate, 2-acrylamido 2-methylpropanesulfonic acid, etc.).

Although such monomers can also impart an emulsion stabilizing effect, it is desirable to use them in an amount of 3% or less based on the total monomers, particularly in order to accelerate curing. Other examples include vinyl chloride, vinylidene chloride, vinyl acetate, and ethylene.

The above solution polymerization may be carried out according to usual conditions, for example, monomers a to (c) may be mixed all at once and reacted in a batch manner, or may be reacted in a continuous dropwise manner.

Polymerization temperature is 50~150oo, polymerization time is 1~1
He may take his time. Through such solution polymerization, a solution system containing the vinyl copolymer is obtained, and it can be used as is. is 2
If it is set to 5 qo or less, the influence of humidity will be significantly reduced when the target resin aqueous dispersion is made into a paint and this is painted.

That is, dry spraying at low humidity and sagging at high temperature are reduced, and coating unevenness due to differences in the surface condition of the object to be coated is also reduced. Particularly effective for metallic paint.
The vinyl resin aqueous dispersion for coating according to the present invention is prepared by adding various ethylenically unsaturated monomers in the presence of the above-mentioned vinyl copolymer having an acid value of 30 to 200 KOH and neutralized with an appropriate agent. It is produced by polymerizing the body in an aqueous medium (hereinafter referred to as emulsion polymerization).

The vinyl copolymer itself has an emulsion stabilizing effect, but before it can be used in a polymerization system, it must neutralize some or all of its carboxyl groups and dissolve or disperse it in water. This neutralization treatment does not need to be completed before being subjected to the polymerization system, and can be achieved by using the vinyl copolymer and a neutralizing agent together. As the neutralizing agent, usual ones may be used, such as alkaline inorganic compounds (potassium hydroxide, sodium hydroxide, potassium carbonate, etc.) and organic amines (monomethylamine, dimethylamine, trimethylamine, monoethylamine, etc.). , water-soluble amines represented by diethylamine, triethylamine, monopropylamine, dimethylpropylamine, etc.
Monoethanolamine, jetanolamine, triethanolamine, N-methylethanolamine, N-aminoethylethanolamine, N-methyldiethanolamine, monoisof.

These include water-soluble oxime amines such as diisopro/f-nolamine, triisopro/gnolamine, monobutanolamine, etc., and polyhydric amines such as ethylenediamine and jethylenetriamine. 1 or 2 selected from the group
A mixture of more than one species may be used. The ethylenically unsaturated single star to be subjected to the emulsion polymerization may be selected from monomers a to c used in the synthesis of the vinyl copolymer, depending on the coating performance and application of the target resin aqueous dispersion. arbitrarily 1
These may be used as a species or in combination of two or more, and in addition to these, glycidyl group-containing ethylenically unsaturated monomers (for example, glycidyl acrylate, glycidyl methacrylate, methylglycidyl acrylate, methylglycidyl methacrylate, etc.) or vinyl groups may be used. An appropriate amount of an unsaturated monomer having two or more of (for example, vinylstyrene, butadiene, polyethylene glycol diacrylate, etc.) may be added.

If such monomers are non-functional, a thermoplastic aqueous resin dispersion is obtained, whereas if they are functional, a thermosetting (or suitable for thermosetting) resin aqueous dispersion is obtained. You get a body. An example of a specific monomer combination is as follows. [i'For thermoplastics: esters of acrylic or methacrylic acid with C, ~, 8 monoalcohols, alkenyl aromatic monomers, nitriles of ethylenically unsaturated carboxylic acids, and other non-functional monomers. A combination whose main component is the body.

(ii) In the case of thermosetting: 30 or more esters of acrylic acid or methacrylic acid and C, ~, 8 monoalcohol, 5 to 40% of ethylenically unsaturated monomers containing hydroxyl groups, and other monomers A combination consisting of 0-65%.

In this case, a hydroxyl group-containing ethylenically unsaturated monomer is used, but generally such a monomer is miscible with water and migrates to the aqueous phase during polymerization, where it is polymerized and becomes water-soluble or It becomes a water-dispersible polymer and dissolves in the water phase or adsorbs on the surface of resin particles. Therefore, the amount of the monomer distributed in the resin particles decreases, resulting in a shortage of effective crosslinkable points. Therefore, even if a crosslinking agent is added to the obtained aqueous resin dispersion to form a baked coating film, a uniform crosslinking reaction cannot be obtained and solvent resistance tends to be poor. Therefore, it is desirable to select and use a hydroxyl group-containing ethylenically unsaturated monomer that is relatively sparingly soluble or immiscible in water. Specific examples include the general formula, [wherein R4 and R5 are the same or different and are a hydrogen atom or a methyl group, R6 is a C3-6 alkylene group, and m is R6 is a C3,4
2 to 10 in the case of an alkylene group and 1 in other cases
- represents 5.

], methalyl alcohol, adducts of dimethylolpropionic acid and glycidyl group-containing ethylenically unsaturated monomers, 3-chloro-2-hydroxypropyl methacrylate, etc. In particular, monomers of the above single-prong type [ m〕
Monomers represented by are preferred.

Examples of the other monomers include alkenyl aromatic monomers, substituted amides of ethylenically unsaturated carboxylic acids,
Ethylenically unsaturated monomers containing blocked isocyanate groups, ethylenically unsaturated monomers containing glycidyl groups, and the like are suitable.

As mentioned above, when the alkenyl aromatic monomer is used, the effect of improving the gloss and transparency of the coating is achieved, and usually 40% of the total monomers are used.
It is desirable to use less than %.

If it exceeds 40%, weather resistance tends to decrease.

When the above-mentioned substituted amides of ethylenically unsaturated carboxylic acids or ethylenically unsaturated monomers containing blocked isocyanate groups are used, the target resin aqueous dispersion can be made into a self-crosslinking type, and each contains 30% of the total monomers. % or less.
When the above-mentioned glycidyl group-containing ethylenically unsaturated monomer is used, under certain conditions, the glycidyl group undergoes an addition reaction with the carboxyl group of the vinyl copolymer during emulsion polymerization, and the emulsion stabilizer becomes a polymer resin particle. The effect of further improving the stability of the resulting aqueous resin dispersion, the transparency, mechanical strength, and other properties of the coating is produced.

On the other hand, if measures are taken to prevent the addition reaction between glycidyl groups and carboxyl groups during emulsion polymerization, a self-crosslinking resin water derivative can be obtained. The amount used may be changed as appropriate depending on the purpose; that is, if the purpose is to improve the film, the glycidyl group should be 10 mol% or less with respect to the carboxyl group, and if the purpose is to create a self-crosslinking type may be selected so that the glycidyl group accounts for 70 to 120 mol% relative to the carboxyl group. In the above emulsion polymerization, since the vinyl copolymer in a neutralized state can be used as an emulsion stabilizer as described above, any known emulsion polymerization method can be used, except that ordinary emulsifiers and surfactants are not used. Polymerization method can be applied.

For example, in an aqueous medium (water or a suitable hydrophilic solvent) set at the polymerization temperature in the presence of a polymerization catalyst,
The reaction components (specifically, the vinyl copolymer, neutralizing agent, and ethylenically unsaturated monomer) can be mixed all at once and reacted batchwise, or each reaction component can be appropriately distributed and reacted separately and continuously. It may be added dropwise to react. The polymerization temperature is 0 to 1
0000, preferably 30-9000, polymerization time 1-9000
One field time may be adopted. During emulsion polymerization, the amount of the emulsion stabilizer used can itself be a film-forming component, so it may be determined appropriately depending on its emulsion stabilizing effect and film performance, and usually the total amount of ethylenically unsaturated monomers used for polymerization. It may be selected within the range of 5 to 70%. Examples of the polymerization catalyst include inorganic peroxides such as potassium persulfate, ammonium persulfate, hydrogen peroxide, and sodium percarbonate; organic peroxides such as penzoyl peroxide and di-t-butyl peroxide; 2,4
Examples include azo compounds such as -dimethylvaleronitrile, and redox catalysts in which peroxide is combined with reducing agents such as potassium pyrosulfite, sodium bisulfite, and triethanolamine. It may be used as a mixture.

The amount used may be normally selected within the range of 0.01 to 5% based on the total amount of reaction components. In this emulsion polymerization, if necessary, a conventional chain transfer agent such as mercaptans such as n-octyl mercaptan and t-dodecyl mercaptan, disulfides such as diisopropylsantogen disulfide, and halides may be used. Alternatively, modifying resins such as alkyd resins and acrylic resins that do not have or have graft active groups, curing agents such as aminoplast resins and polyfunctional block isocyanates, and pigments may be blended. Emulsion polymerization can also be carried out.

The aqueous vinyl resin dispersion produced as described above exhibits excellent storage stability even when an appropriate organic solvent (alcohols, ethers, etc.) is added when it is made into a paint for the intended purpose. By combining the types of polymerization monomers (ethylenically unsaturated monomers), it can be applied to thermoplastic or thermosetting coatings, either as is or as needed with aminoplast resins, polyfunctional A curing agent such as a block isocyanate, an epoxy resin, a pigment, an antifoaming agent, a surface conditioner, etc. may be added, and other water-based resins may be added to form a paint.

Coating is carried out by commonly used methods such as spray coating, immersion coating, decoating coating, roll coating, brush coating, etc., and is dried and cured at room temperature or by heating to achieve various desired properties such as gloss and transparency. Forms coatings with excellent properties such as strength, mechanical strength, water resistance, boiling water resistance, corrosion resistance, chemical resistance (acid resistance, alkali resistance), solvent resistance, stain resistance, heat resistance, film resistance, etc. can do. From this,
It can be said that the aqueous vinyl resin dispersion obtained by the method of the present invention is suitable for use in high-grade top coatings. Next, the present invention will be specifically explained by giving Examples, Comparative Examples, and Reference Examples.

Note that "parts" and "%" in the example sentences mean "parts by weight" and "% by weight." Example 1 A reactor equipped with a condenser, an inert gas inlet pipe, and a rope strainer was charged with 36% of diethylene glycol monobutyl ether.
$ parts, 62.2 parts of acrylic acid, 166.5 parts of polyethylene glycol monomethacrylate (number of repeating ethylene oxide units (n): approximately 5), 4.1 parts of 2-acrylamido-2-methylpropanesulfonate 92 parts of methyl methacrylate, 125.9 parts of n-butyl methacrylate, 193 parts of n-butyl acrylate. Abe, Styrene 276
parts, 24.7 parts of t-dodecyl mercaptan and 2,2 parts
'-Add 12.3 parts of azobisisobutyronitrile,
Reaction was carried out at a temperature of 120° C. for 4 hours under a nitrogen gas stream to obtain a pinyl copolymer solution.

The copolymer in the solution had a concentration of about 5 OH and a number average molecular weight of about 11,000. The solution was cooled to 80 qo, and 149 qo of 2-hydroxyethyl methacrylate was added to it.
．． 4 parts, N-ptoxymethylacrylamide 186.5
216 parts of methyl methacrylate, 108 parts of n-butyl methacrylate, 96.1 parts of n-butyl acrylate and 324 parts of styrene were added to make a homogeneous solution, and after cooling to room temperature, 76 parts of dimethylethanolamine was added. , melamine-formaldehyde resin (product name: Cymer 303, manufactured by American Cyanamid Co.) 50 groups and 2,2'
-azobis-2,4-dimethylvaleronitrile 43.2
A homogeneous solution (hereinafter referred to as solution A) is obtained. Next, 2850 parts of deionized water was charged into a reactor equipped with a cooler, an inert gas inlet pipe, a rope scaler, and a dropping device, and the temperature under the frame was maintained at 7000°C. The entire amount is added dropwise over a period of 3 hours. After the dropwise addition is completed, the mixture is reacted at the same temperature for 2 hours to obtain a milky-white aqueous vinyl resin dispersion for coating with an uncured content of 46.5% and a viscosity (using a B-type viscometer, the same applies hereinafter) of 65 ps. To 10 Makoto Ikari of the above resin aqueous dispersion, 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol were added and stored at 40 oo for 1 hour, but it remained uniform and stable with no changes such as thickening or aggregation. there were.

Example 2 In the same reactor as in Example 1, 31. $ county, acrylic acid 56.
7 parts Same as Example 1 Polyethylene glycol monomethacrylate 76.4 parts, 2-hydroxyethyl methacrylate 35 parts, 2-acrylamido-2-methyl-propanesulfonic acid 3.8 parts, methyl methacrylate 95.8 parts 107.5 parts of n-butyl methacrylate, 199.5 parts of n-butyl acrylate, 223.4 parts of styrene, 22.6 parts of t-dodecylmercaptan, and 11.5 parts of 2,2'-azobisisobutyronitrile. 3 parts were charged and reacted at a temperature of 12,000 for 4 hours under nitrogen gas flow to obtain a vinyl copolymer solution.

The acid value of the copolymer in the solution is about 52. The number average molecular weight was about 9,400 on the evening of Uta OH on September 9th. This solution was cooled by 80q, and polypropylene glycol monomethacrylate (number of repeating propylene oxide units (m):
4 parts) 273.4 parts, N-butoxymethylacrylamide 199.5 parts, glycidyl methacrylate 10.7 parts, 3-chloro-2-acid phosphooxypropyl methacrylate 4.8 parts, methyl methacrylate 357. $ parts, n-butyl methacrylate 130.2 parts, acrylic acid n
- 195.3 parts of butyl and 130.2 parts of styrene were added to make a homogeneous solution, and after cooling to room temperature,
A homogeneous solution (hereinafter referred to as solution B) was prepared by adding 40 parts of dimethylethanolamine and 39.1 parts of 2,2'-azobis-2,4-dimethylvaleronitrile. Next, 3322 g of deionized water was charged into the same reactor as in Example 1, and the temperature was maintained at 70oC, and the entire amount of the above solution B was added dropwise thereto over a period of 3 hours in a nitrogen gas stream.

After the dropwise addition was completed, the reaction was carried out at the same temperature for 2 hours, and the non-volatile content was 43.
A milky white aqueous dispersion of pinyl resin for coating is obtained with a viscosity of 0% and a viscosity of 50 ps. When 10 parts of the above resin aqueous dispersion were added with 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol and stored at 4000 °C for 1 hour, a slight increase in viscosity was observed, but no aggregation occurred. I was not able to admit.

Example 3 In the same reactor as in Example 1, 3 parts of ethylene glycol monoethyl ether, 38.3 parts of acrylic acid,
Same as Example 1: 187.5 parts of polyethylene glycol monomethacrylate, 3.8 parts of 2-acrylamido-2-methyl-propanesulfonic acid, 205 parts of methyl methacrylate.
．． 5 parts, n-butyl methacrylate 75 parts, acrylic acid n
127.5 parts of -butyl, 112.5 parts of styrene, 22.5 parts of t-dodecyl mercaptan and 11.3 parts of 2,2'-azobisisobutyronitrile were charged, and the mixture was heated under a stream of nitrogen gas. A vinyl copolymer solution was obtained by reacting at a temperature of 12,000 for 4 hours.

The acid value of the copolymer in the solution was about 40 KOH, and the number average molecular weight was about 7,100. This solution was cooled to 80 oo, and to this were added 262.5 parts of polypropylene glycol monomethacrylate, the same as in Example 2, 175 parts of N-butoxymethylacrylamide, 12.3 parts of 3-chloro-2-acid phosphooxypropyl methacrylate, 437.5 parts of methyl methacrylate, 26 parts of n-phthyl methacrylate
2.5 parts of n-butyl acrylate, 274.8 parts of n-butyl acrylate, and 35 parts of styrene were added to make a homogeneous solution, and after cooling to room temperature, 37 parts of dimethylethanolamine was added. $ part and 2,2
'-Azobis-2,4-dimethylvaleronitrile52.
5 parts were added to form a homogeneous solution (hereinafter referred to as C solution). Next, 3886 parts of deionized water was charged into the same reactor as in Example 1, and the temperature was maintained at 7° C., and the entire amount of the above C solution was added dropwise thereto over a period of 3 hours in a nitrogen gas stream.

After the dropwise addition was completed, the reaction was carried out at the same temperature for 2 hours, and the non-volatile content was 42.
A milky white aqueous vinyl resin dispersion for coating is obtained with a viscosity of 8% and a viscosity of 55 ps. 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol were added to 1 bottle of the above resin aqueous dispersion, and the mixture was stored at 40 qo for 1 hour.
It was uniform and stable, with no changes such as thickening or aggregation.

Example 4 Into the same reactor as in Example 1, 27 parts of diethylene glycol monobutyl ether, 39.2 parts of acrylic acid, 101.3 parts of polyethylene glycol monomethacrylate same as in Example 1, and 2-hydroxyl acrylic acid were added. .

Lopil 33.8 parts, 2-acrylamido-2-methyl-propanesulfonic acid 3.4 parts, methyl methacrylate 13
5 parts, 202.5 parts of n-butyl methacrylate, 16 parts of n-butyl acrylate, 101.3 parts of styrene, 20.3 parts of n-dodecylmercaptan, and 10 parts of 2,2'-azobisisobutyronitrile. A vinyl copolymer solution was obtained by charging 1 part of the copolymer and reacting it at a temperature of 12,000 for 4 hours under a nitrogen gas stream for 4 hours. The polymer in the solution had an acid value of about 40OH and a number average molecular weight of about 6,900. The solution was cooled to 80°C, and 283.5 parts of 1,6-hexanediol monomethacrylate and 1 part of 3-chloro-2-acid phosphooxypropyl methacrylate were added to the solution.
1 part, 472.5 parts of methyl methacrylate, 256.7 parts of n-butyl methacrylate, 236 parts of n-butyl acrylate
．． 3 parts and 315 parts of styrene were added to make a homogeneous solution, and after cooling to room temperature, 250 parts of Cymer 303, 48.5 parts of dimethylethanolamine, and 47.3 parts of 2,2-azobis-2,4-dimethylvaleronitrile were added. 1 part to form a homogeneous solution (hereinafter referred to as solution D). Next, 3395 parts of deionized water was charged into the same reactor as in Example 1, and the temperature was maintained at 70q0, and the entire amount of the above solution D was added dropwise thereto over a period of 3 hours in a nitrogen gas stream.

After the dropwise addition was completed, the reaction was carried out at the same temperature for 2 hours, and the non-volatile content was 43.
A milky white aqueous vinyl resin dispersion for coating is obtained with a viscosity of 6% and a viscosity of 43 ps. To 10 parts of the above resin water dispersion, 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol were added, and the mixture was stored at 40°C for 1 hour.
It was uniform and stable, with no changes such as thickening or aggregation.

Example 5 In the same reactor as in Example 1, 20 parts of diethylene glycol monobutyl ether, 45 parts of acrylic acid, and polyethylene glycol monomethacrylate (number of repeating ethylene oxide units (n): approximately 9) ) 15 Ikaribe, 2-
Acrylamide 2-methylpropanesulfonic acid 2.5
15 parts of methyl methacrylate, 52.5 parts of n-butyl acrylate, 100 parts of styrene, 15 parts of n-dodecylmercaptan and 7.5 parts of 2,2'-azobisisobutyronitrile were charged, and nitrogen gas was added. Reaction was carried out at a temperature of 12,000 for 4 hours under air flow to obtain a pinyl copolymer solution.

The copolymer in the solution had an acid value of about 70 KOHm9 and a number average molecular weight of about 8,300. This solution was cooled to 80 qo, and to this were added 40 parts of the same polypropylene glycol monomethacrylate as in Example 2, 40 parts of glycidyl methacrylate, 14 parts of 3-chloro-2-acid phosphooxypropyl methacrylate, 646 parts of methyl methacrylate, 20 parts of n-butyl methacrylate, 40 parts of n-butyl acrylate and 30 parts of styrene were added to make a homogeneous solution, and after cooling to room temperature, 5 parts of dimethylethanolamine was added.
5.6 parts and 6 parts of Pennzoilver oxide were added to form a homogeneous solution (hereinafter referred to as solution E). Next, 3563 parts of deionized water was charged into the same reactor as in Example 1, and the temperature was maintained at 70o0, and the above-mentioned E
The entire solution was added dropwise over a period of 3 hours.

After the dropwise addition was completed, the reaction was carried out at the same temperature for 2 hours, and the non-volatile content was 41.
5% and a viscosity of 81 ps to obtain a milky-white coating vinyl resin moisture admixture. To 10 pieces of the above resin water dispersion, 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol were added, and the mixture was stored at 40q0 for 1 hour.
It was uniform and stable, with no changes such as thickening or aggregation.

Example 6 In the same reactor as in Example 1, ethylene glyco-
2 parts of monoethyl ether, 64 parts of acrylic acid, methoxypolyethylene glycol mono-4 methacrylate (number of repeating ethylene oxide units (n): approximately 5) 15
Anchorage, 5 anchorages of methyl methacrylate, 186 parts of n-butyl acrylate, 50 parts of styrene, 17.5 parts of t-dodecylmercaptan and 7.5 parts of 2,2'-azobisisobutyronitrile were charged, and nitrogen gas was added. A vinyl copolymer solution was obtained by reacting at a temperature of 120° C. for 4 hours while blowing in an air stream.

The copolymer in the solution had an acid value of about 100 KOH, 9 knots, and a number average molecular weight of about 6,200. 8000 ml of such solution
4 parts of glycidyl methacrylate, 36 parts of methyl methacrylate, and 140 parts of n-butyl acrylate.
0 parts and 20 parts of styrene were added to make a homogeneous solution, and after cooling to room temperature, 79.1 parts of dimethylethanolamine was added.
1 part to form a homogeneous solution (hereinafter referred to as F solution). Next, 318 parts of deionized water was charged into the same reactor as in Example 1, and the temperature was kept at 7000, and the entire amount of the above F solution, 2 parts of ammothane persulfate, and deionized water were added to the reactor in a nitrogen gas stream. A mixture consisting of 40 ml of water was added dropwise over a period of 3 hours.

After the dropwise addition was completed, the reaction was carried out at the same temperature for 2 hours, and the non-volatile content was 40.
A milky-white aqueous vinyl resin dispersion for coating is obtained with a viscosity of 9% and a viscosity of 21&ps. To 10 pieces of the above resin water dispersion, 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol were added, and when stored at 40°C for 1 hour, it was uniform with no changes such as thickening or aggregation. It was stable.

Comparative Example 1 In the same reactor as in Example 1, 32 parts of diethylene glycol monobutyl ether, 72 parts of acrylic acid, 96 parts of 2-hydroxyethyl methacrylate, 240 parts of methyl methacrylate, and 192 parts of n-butyl methacrylate were added. parts, n-butyl acrylate 12 parts, styrene 160 parts, t-
21.6 parts of dodecyl mercaptan and 11.2 parts of 2,2-azobisisobutyronitrile were charged and reacted at a temperature of 120° C. for 4 hours under a nitrogen gas stream to obtain a vinyl copolymer solution.

The copolymer in the solution had an acid value of about 70 KOH and a number average molecular weight of 8,600. The solution was cooled to 80°C, and 144 parts of 2-hydroxyethyl methacrylate, 396 parts of methyl methacrylate, 24 parts of n-butyl methacrylate, 18 parts of n-butyl acrylate, and 24 parts of styrene were added. After making a homogeneous solution and cooling it to room temperature, 50 parts of Cymer 303, 8 parts of dimethylethanolamine, and 48 parts of 2,2'-azobis-2,4-dimethylvaleronitrile were added to make a homogeneous solution (hereinafter referred to as G solution). ). Next, in the same reactor as in Example 1, 3605 parts of deionized water was charged, the pre-condensation temperature was maintained at 70q0, and the entire amount of the above G solution was added dropwise thereto over a period of 3 hours in a nitrogen gas stream.

After the dropwise addition was completed, the reaction was carried out at the same temperature for 2 hours, and the non-volatile content was 44.
A milky white resin water dispersion is obtained with a viscosity of 1% and a viscosity of 46 ps.
When 5 parts of diethylene glycol monobutyl ether and 5 parts of ethanol were added to 10 pieces of the above resin water dispersion and stored at 4,000 ℃ for 1 hour, the viscosity increased significantly and some parts became cake-like. It was showing.

Reference Example 1 10 parts of the resin aqueous dispersion obtained in Example 2 or Comparative Example 1, 5 parts of diethylene glycol monobutyl ether, 5 parts of ethanol and 7.5 parts of aluminum paste were added and thoroughly dispersed and mixed to form a coating solution. create.

The paint solution was then poured into food cup no. 4 in 3
After adjusting the viscosity so that it becomes horse chestnut sand, spray coating is applied at a discharge rate of 21 c/min. The objects to be coated were iron plates coated with a cured coating film of thermosetting alkyd resin; ■ areas polished with sandpaper and water, ■ areas polished with sandpaper in the absence of water, and ■ It has unpolished parts. Also, the painting environment is temperature 2500 and humidity 50.
, 70, and 90%, and competitive drying was performed by preheating at 7500 for 1 minute and then baking at 150 qo for 3 minutes. As a result of the above coating, the one using the resin water dispersion of Example 2 was as follows:
It was less affected by differences in the surface condition and humidity of the object to be coated, gave the same good metallic feel as a whole, and exhibited a finished appearance with no metallic unevenness. On the other hand, in the case of using the resin water dispersion of Comparative Example 1, at a humidity of 70%, the parts polished in the absence of water looked different from other parts, resulting in metal unevenness and coating unevenness.

Claims (1)

[Claims] 1 a General formula ▲ Numerical formula, chemical formula, table, etc. ▼ [In the formula, R_1 and R_2 are the same or different and are a hydrogen atom or a methyl group, and R_3 is a hydrogen atom or a C_
1 to C_3 alkyl group, and n represents 2 to 20. ], b. ethylenically unsaturated carboxylic acid, and c. other ethylenically unsaturated monomers. Yes▼ [In the formula, R_1, R_2, R_3 and n have the same meanings as above. ] has 5 to 40% by weight of units represented by
A method for producing an aqueous vinyl resin dispersion for coating, which comprises polymerizing an ethylenically unsaturated monomer in an aqueous medium in the presence of ~200 KOHmg/g of a vinyl copolymer in a neutralized state. 2. Other ethylenically unsaturated monomers include esters of acrylic acid or methacrylic acid and monoalcohols of C_1 to_1_8, hydroxyl group-containing ethylenically unsaturated monomers, alkenyl aromatic monomers, ethylenically unsaturated Amides of carboxylic acids and substituted amides thereof, nitriles of ethylenically unsaturated carboxylic acids, diesters of ethylenically unsaturated dicarboxylic acids, addition reaction products of glycidyl acrylate or glycidyl methacrylate with fatty acids, acrylic acid or methacrylic acid and epoxy resins addition reaction product with blocked isocyanate group-containing ethylenically unsaturated monomer,
and one or a mixture of two or more selected from the group of phosphoric acid group-containing or sulfonic acid group-containing ethylenically unsaturated monomers. 3 The combination of ethylenically unsaturated monomers subjected to polymerization in an aqueous medium is acrylic acid or methacrylic acid and C_1
The method according to item 1 above, wherein the main components are esters with monoalcohols of ~_1_8, alkenyl aromatic monomers, nitriles of ethylenically unsaturated carboxylic acids, and other non-functional monomers. 4 The combination of ethylenically unsaturated monomers subjected to polymerization in an aqueous medium is acrylic acid or methacrylic acid and C_1
~_1_8 ester with monoalcohol 30% by weight or more, hydroxyl group-containing ethylenically unsaturated monomer 5-4
0% by weight and 0 to 65% by weight of other monomers. 5 Hydroxyl group-containing ethylenically unsaturated monomers have general formulas, ▲mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R_4 and R_5 are the same or different and are hydrogen atoms or methyl groups, R_6 is C_3 to _6 The alkylene group and m represent 2 to 10 when R_6 is a C_3,_4 alkylene group, and 1 to 5 in other cases. ] The method according to the above item 4, which is a monomer represented by the following. 6. The method according to item 4 above, which comprises a phosphoric acid group- or sulfonic acid group-containing ethylenically unsaturated monomer as one component of the other monomers. 7. The method according to item 6 above, wherein the phosphoric acid group- or sulfonic acid group-containing ethylenically unsaturated monomer is a monomer that is sparingly soluble in water or immiscible in water.