JPS5844098B2 - Water-dispersed thermosetting coating composition - Google Patents

Description

[Detailed description of the invention] The present invention relates to water-dispersed thermosetting coating compositions.

More specifically, the present invention relates to a non-yellowing water-dispersed thermosetting coating composition that has excellent storage stability, forms a coating film with excellent corrosion resistance, corrosion resistance, and water resistance.

BACKGROUND ART In recent years, efforts have been made to make paints and coatings pollution-free and resource-saving, and powder coatings and water-based coatings are increasingly being used as coatings suitable for this purpose.

However, such powder coatings require special coating equipment, are not as easy to apply as conventional solvent-based coatings, and have excellent coating film smoothness and a difficult-to-image finished appearance.
It has problems in use, such as difficulty in applying it to a thin film of 0μ or less.

Furthermore, among water-based paints, water-soluble paints have a low solid content concentration during painting, so it is difficult to apply a thick film at once. The problem was that the durability could not be achieved.

on the other hand. Emulsion paints have had the problem of poor water resistance, chemical resistance, etc. of the paint film because they use a large amount of surfactant.

As a method to solve these problems, a slurry paint (water-dispersed paint) has been proposed in which resin powder is suspended in water and applied like a water-based paint.

In general, acrylic resins, polyester resins, epoxy resins, alkyd resins, etc. are known as resins used in such slurry paints, but they are especially important for stability during storage, smoothness of the coating film, and finish. Acrylic resin and polyester resin are said to be preferable from the viewpoint of appearance.

Types of crosslinking reactions for these resins include a self-curing type and a type using a crosslinking agent or a curing agent.

Such crosslinking agents or curing agents include melanin resins,
Blocked isocyanate compounds etc. are used, but
Furthermore, epoxy resin or the like may be used in combination to provide anti-corrosion properties.

By the way, when melanin resin is used as a cross-linking agent, if a thick film is applied, foaming (flanks) may sometimes occur during baking, so there is a drawback in terms of painting workability. I needed to.

Further, in order to prevent the above-mentioned foaming, urethane (blocked isocyanate compound) combination systems are used, but these have the disadvantage that they sometimes yellow when baked at high temperatures.

(JP-A-50-112428, JP-A-52-10843
3).

Additionally, since slurry paints generally use water,
When painted directly onto iron plates such as mild steel plates, similar to conventional water-based paints, there is the problem of temporary rusting and other phenomena that are not seen with solvent-based paints.

In order to suppress this phenomenon, temporary rust preventive agents and the like are often used in the same way as water-based paints, but the use of these agents is not preferable because it has an adverse effect on storage safety.

The present invention aims to solve these problems.

In other words, it is a non-yellowing type with excellent storage safety, has a wide working width, and has no drawbacks such as wrinkles due to seizure, and has coating properties such as gloss, smoothness, temporary rust prevention, corrosion resistance, and water resistance. The present invention provides an excellent water-dispersible thermosetting coating composition.

That is, the present invention provides (A) (i) an acid value of 50 or less, a hydroxyl value of 50 to 250, and a weight average molecular weight of 2.000, which has an α,β-unsaturated dicarboxylic acid having a weight coefficient of 1 to 10 as one of the constituent components; ~20,000 unsaturated polyesters...
...2 to 40 weight factor (i) (a) Hydroxyalkyl ester of α,β-monoethylenically unsaturated carboxylic acid...1 to 30 weight factor (ro) ) N-alkoxymethylated monomer of α, β-monoethylenically unsaturated carboxylic acid amide
- 5 to 30 weight ratio (c) Copolymerizability α other than the above (a), (b) and (Bl(i)).

A monomer mixture consisting of β-monoethylenically unsaturated monomer......60 to 90 weight percentage...98 to 60 weight percentage is graft polymerized. Obtained hydroxyl value 10-150
, acid value 3-40. Weight average molecular weight 40.000-200
,000 polyester modified vinyl resin...
...15-95 weight section (B) (i) +
) monoethylenically unsaturated monomer containing acid group
・・・・・・・・・0.01~10 Weight Section (11)
α, β-monoethylenically unsaturated carboxylic acid...
...0.5 to 10 weight range (iii) Hydroxyalkyl ester of α,β-monoethylenically unsaturated carboxylic acid ...1 to 30 weight range (iV) (A) ( ii) (o), Q3XiL(
BXii) Copolymerizable α, β other than Oyobi (BXiii)
-Monoethylenically unsaturated monomer...
Phosphoric acid group-containing copolymer resin having a weight average molecular weight s, ooo ~ 70,000, obtained from a monomer mixture consisting of a weight ratio of 70 to 90... 85 to 85
A temporary composition consisting of finely powdered thermosetting resin particles having a weight ratio of 5 to 10% by weight, a surfactant and/or thickener in a range of 0.01 to 1.0 weight relative to the particles, and the required amount of water. This invention relates to a water-dispersible thermosetting coating composition with excellent rust prevention properties.

The polyester-modified vinyl resin used in the present invention is obtained by graft polymerizing an α,β-monoethylenically unsaturated monomer mixture [above (A1(iil)] to an unsaturated polyester; It is characterized by imparting to vinyl resin the flexibility, pigment dispersibility, and excellent coating appearance that polyester has.

It is necessary to use an α,β-unsaturated dicarboxylic acid as a raw material for the unsaturated polyester used in the present invention.

The components are preferably reacted in an amount of 1 to 10% by weight, preferably 3 to 7% by weight, in the unsaturated polyester.

That is, if the amount of the component is less than 1 weight, the amount is not sufficient for the α,β-monoethylenically unsaturated monomer when producing the polyester-modified vinyl resin, and therefore the polyester modification becomes insufficient. The product has a composition that is a blend of unsaturated polyester and a polymer of α,β-monoethylenically unsaturated monomer, which may cause whitening of the coating film or due to the difference in reactivity with the crosslinking monomer. , coating film performance, especially adhesion, tends to decrease.

On the other hand, when the weight ratio of the component is 10 or more, gelation occurs during the reaction with the α,β-monoethylenically unsaturated monomer, which is not preferable.

Specific examples of the components include fumaric acid, maleic acid (anhydride), itaconic acid, glutaconic acid, and citraconic acid (anhydrous), and one type or a mixture of two or more of these may be used.

In the synthesis of the unsaturated polyester used in the present invention, the carboxylic acid component other than the acid group is preferably 29 to 69
Make it react according to the weight ratio.

Specific examples of the components include phthalic anhydride, isophthalic acid, trimellitic acid (anhydride), pyromellitic acid (anhydride), tetrahydrophthalic acid (anhydride), hexahydrophthalic acid (anhydride), and methyltetrahydro (anhydrous). phthalic acid,
Examples include methylhexahydrophthalic anhydride, hymic anhydride, conohydric acid, adipic acid, sebacic acid, benzoic acid, para-tert-butylbenzoic acid, etc.
These may be used alone or in a mixture of two or more.

In the synthesis of the unsaturated polyester used in the present invention, the polyhydric alcohol component is preferably reacted in a proportion of 30 to 70% by weight.

Specific examples of the components include ethylene glycol, diethylene glycol, phlopylene gellicol, neopentyl glycol, dipropylene glycol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, phthanediol, bentanediol, hexanediol. , 1.4-
Cyclohexane dimetatool, (hydrogenated) bisphenol A, etc. are used, and one or a mixture of two or more of these is used, and if necessary, Cardular E (manufactured by Shell Chemical Co., Ltd., trade name) is used in combination.

In addition, animal and vegetable oils and their fatty acids, petroleum resins,
Rosin, phenolic resin, epoxy resin, etc. can also be used.

The unsaturated polyester in the present invention is produced by a single-stage reaction or a multi-stage reaction by a known method, and there are no restrictions on the reaction method.

Further, a polymerization solvent described below can be used as a diluent if necessary.

The acid value of the unsaturated polyester of the present invention is 50 or less (resin solid content; hereinafter, all acid values of the present invention are expressed in the same manner),
The hydroxyl value is 50 to 250 (resin solid content; hereinafter, all hydroxyl values in the present invention are expressed in the same way), and the molecular weight is 2,000 to 20,000 in weight average molecular weight.

The weight average molecular weight was measured by gel permeation chromatography (Model A301 manufactured by Toyo Qta).

Hereinafter, the weight average molecular weight in the present invention was measured in the same manner.

In the present invention, the unsaturated polyester has an acid value of 50
If it is more than that, the alkali resistance etc. in the final coating film performance after graft polymerization of the α,β-monoethylenically unsaturated monomer will decrease.

Furthermore, if the hydroxyl value is lower than 50, the crosslinkability between the polyester-modified vinyl resin obtained by graft polymerization of α,β-monoethylenically unsaturated monomer and the phosphoric acid group-containing copolymer resin tends to be insufficient, and if the hydroxyl value is lower than 250, When it is high, the secondary properties of the resulting coating film tend to decrease due to the increase in polar groups.

In addition, if the weight average molecular weight is lower than 2000, the properties of unsaturated polyester cannot be fully exhibited;
If it exceeds 000, the molecular weight of the unsaturated polyester is too high, and when it is modified with an α,β-monoethylenically unsaturated monomer, it becomes too clayey, which may impede workability.

In the polyester-modified vinyl resin of the present invention, an N-alkoxymethylated monomer of α,β-monoethylenically unsaturated carboxylic acid amide ((i
i) (b)], [α,β-monoethylenically unsaturated saturated carbonyloxyalkyl ester ((iiXi)],
The above (r*) (a), (ii) (b) and (B)
It is obtained by graft polymerizing a monomer mixture with a copolymerizable β-monoethylene glycol unsaturated monomer other than (i).

In addition, the polyester modified vinyl resin in the present invention needs to contain a hydroxyl group in the molecule in order to carry out a crosslinking reaction with the phosphoric acid group-containing copolymer resin and a self-crosslinking reaction.

Therefore, the hydroxyalkyl ester of the α,β-monoethylenically unsaturated carboxylic acid has α,
β-monoethylenic monomer mixture [(A) (ii) above
It is used in an amount of 1 to 30 parts by weight, particularly preferably 3 to 20 parts by weight.

If the monomer is used in an amount exceeding 30% by weight, the polyester-modified vinyl resin will have a high clay content, and the crosslinking density after the thermosetting reaction with the phosphoric acid group-containing copolymer resin will become too high, resulting in poor coating film quality. The flexibility, water resistance, etc. tend to deteriorate, which is undesirable.

Specific examples of the monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 3-hydroxypropyl (meth)acrylate.
-Hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (
meth)acrylate, neopentyl glycol mono(meth)acrylate, 3-butoxy-2-hydroxypropyl(meth)acrylate, 2-hydroxy-1-phenylethyl(meth)acrylate, polypropylene glycol mono(meth)acrylate, glycerin mono(meth)acrylate There are meth)acrylates, etc., and these may be used alone or as a mixture of two or more.

In addition, the N7 alkoxymethylated monomer fraction of the polymerizable α, β-monoethylenically unsaturated carboxylic acid amide used for graft copolymerization with the unsaturated polyester is α,
It is necessary for the crosslinking reaction of β-monoethylenically unsaturated carboxylic acid with the hydroxyalkyl ester component and the unsaturated polyester component.

These components are subjected to a graft copolymerization reaction in a proportion of 5 to 30 weight percent, preferably 10 to 20 weight percent, in the α,β-monoethylenically unsaturated monomer mixture.

If the amount of this component is less than 5% by weight, the crosslinking reaction of the polyester-modified vinyl resin will be insufficient, resulting in a decrease in solvent resistance.

Moreover, if it exceeds 30% by weight, gelation occurs during the graft copolymerization reaction, which is not preferable.

Specific examples of this component include N-methoxymethyl (meth)
Acrylamide, N-ethoxymethyl (meth)acrylamide, N-n-propoxymethyl (meth)acrylamide, N-isopropoxymethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide,
N-5ec-butoxymethyl (meth)acrylamide,
N-1-butoxymethyl(meth)acrylamide, N-
α, β such as isobutoxymethyl (meth)acrylamide
- N-alkoxymethylated products of monoethylenically unsaturated carboxylic acid amides; or N-methylolated products thereof, and the like, and these may be used alone or as a mixture of two or more kinds.

In the present invention, the hydroxyalkyl ester monomer of the α,β-monoethylenically unsaturated carboxylic acid and α
, a monomer other than the N-alkoxymethylated monomer of β-monoethylenically unsaturated carboxylic acid amide is used in combination.

The monomer is used in a range of 60 to 90% by weight in the monomer mixture.

Specific examples of the monomer include α,β-monoethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid; methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (
meth)acrylate, isopropyl(meth)acrylate, n-butyl(7-)acrylate, 5eC-butyl(meth)acrylate, t-butyl(meth)acrylate, isobutyl(meth)acrylate, n-hexyl(
Alkyl esters of acrylic acid or methacrylic acid such as meth)acrylate, 2-ethylhexyl(meth)acrylate, n-octyl(meth)acrylate, lauryl(meth)acrylate, tridecyl(meth)acrylate, and stearyl(meth)acrylate; Others N, N
'-dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, cyclohexyl (meth)
Examples include dialkyl esters of fumaric acid such as acrylate, phenyl methacrylate, benzyl methacrylate, and dibutyl fumarate, and monomers such as styrene, vinyltoluene, α-methylstyrene, (meth)acrylonitrile, and vinyl acetate.

The above monomers may be used depending on the purpose and use of the coating composition.
They can be used as a species or in an appropriate combination of two or more.

The polyester modified vinyl resin contains the unsaturated polyester 2 to 40 monomers and the monomer mixture 60 to 98 monomers.
It consists of a graft polymerization reaction product with a weight ratio.

The amount of modification of the unsaturated polyester is from 2 to 40 parts by weight, preferably from 5 to 30 parts by weight.

If it is less than 2 monomers, the excellent flexibility, pigment dispersibility, and coating film appearance of unsaturated polyester cannot be fully demonstrated, and if it is more than 40 monomers, the characteristics of vinyl resin will not be fully exhibited. Hardness, stain resistance, etc. are impaired.

The polyester-modified vinyl resin of the present invention is produced by conventional solution polymerization.

For example, the remaining monomer (mixture) and a polymerization initiator are added dropwise into a mixture of unsaturated Bossester, part of the monomer (mixture), and a polymerization solvent, and polymerization is carried out, or the unsaturated There is a method in which polyester, a monomer (mixture), and a polymerization initiator are dropped and polymerized, but there is no particular restriction on the solution polymerization method.

As the polymerization solvent used in the solution polymerization method, water-soluble or water-miscible solvents are used, such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-
Alcohols such as propyl alcohol, ethylene glycol derivatives such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate; diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, etc. Diethylene glycol derivatives; esters such as methyl acetate, ethyl acetate, and butyl acetate; and ketones such as methyl ethyl ketone and methyl isobutyl ketone are used.

These polymerization solvents may be used alone or in an appropriate combination of two or more.

In particular, those having a solubility in water of about 10 to 30% by weight at 20°C are preferred.

In addition, examples of the polymerization initiator used include pensoyl peroxide, -j tilperbenzoate, and t-
Organic peroxides such as butyl hydroperoxide, cumene hydroperoxide, di-t-butyl peroxide, t-butyl peroctoate, etc. or ab compounds such as azobisisobutyronitrile, azodiisobutyric acid nitrile, etc. Can be mentioned.

These polymerization initiators may be used alone or in an appropriate mixture of two or more.

If necessary, chain transfer agents such as dodecyl mercaptan, 2-ethylhexyl thioglycolate, carbon tetrachloride, etc. may be used to adjust the molecular weight.

The hydroxyl value of the polyester-modified vinyl resin of the present invention is 10
-150, preferably 20-100, and oxidation is in the range 3-40, preferably 5-25.

When the oxidation value is less than 3, the thermosetting property is insufficient, resulting in poor hardness, water resistance, corrosion resistance, durability, etc. of the coating film.On the other hand, when the acid value is greater than 40, the coating performance and storage stability are also reduced.

Moreover, when the hydroxyl value is 10 or less, the crosslinking density decreases, the solvent resistance decreases, and the solvent resistance decreases.

On the other hand, if it is greater than 150, the flexibility and water resistance will decrease.

The weight average molecular weight of the polyester modified vinyl resin of the present invention is 40. OCo~200,000, preferably 50,
000 to 150,000.

If the weight average molecular weight is 40,000 or less, the coating performance will be insufficient; on the other hand, if the weight average molecular weight is 20,200.0
If it is 00 or more, the smoothness of the coating film will be impaired, which is not preferable.

Next, the phosphoric acid group-containing copolymer resin used in the present invention is
It is obtained by copolymerizing a phosphoric acid group-containing α,β-monoethylenically unsaturated monomer with an α,β-monoethylenically unsaturated monomer other than those mentioned above.

By introducing the phosphoric acid group-containing α,β-monoethylenically unsaturated monomer, even when the coating composition of the present invention is applied directly onto an iron plate, it not only suppresses temporary rusting but also makes it easier to store the composition. It is possible to obtain a coating film that improves stability, has stronger adhesion to metal surfaces, and has significantly superior corrosion resistance and water resistance.

The phosphoric acid group-containing α,β-monoethylenically unsaturated monomer is used in an amount of 0101-10.0 by weight in the monomer mixture, preferably in the range of 0.5 to 5.0 monomers. do.

If 0.01 weight of the monomer is used, the temporary rust prevention effect, storage stability, and high corrosion resistance, which are the characteristics of the present invention, cannot be sufficiently exhibited; If used, it is not preferable because it tends to gel during the polymerization reaction process.

In addition, sufficient effects can be obtained within 10 weight winds, so 1
It is economically undesirable to use more than zero-weight monomer.

Specific examples of the monomer include acidophosphoxyethyl (meth)acrylate, azidophosphoxypropyl (
Primary phosphoric acid esters of acrylic acid or methacrylic acid containing a hydroxyl group such as meth)acrylate, 3-chloro-2-acidophosphoxypropyl methacrylate; bis(meth)acryloxyethyl phosphate, acrylic alcohol acid It is one kind or a mixture of two or more kinds of phosphate, vinyl phosphate, mono[2-hydroxyethyl (meth)acrylate coreside phosphite, etc., and salts and esters thereof.

Such a monomer is prepared by reacting an α-β-monoethylenically unsaturated monomer having a hydroxyl group with phosphoric anhydride,
It is produced by hydrolyzing the product, but it can also be produced using other substances such as orthophosphoric acid, metaphosphoric acid, phosphorus oxychloride, phosphorus trichloride, and phosphorus pentachloride.

The α-β-monoethylenically unsaturated monomers other than the phosphoric acid group-containing α,β-monoethylenically unsaturated monomer used as an essential component in the phosphoric acid group-containing copolymer resin are as described below. , α,β-monoethylenically unsaturated carboxylic acids, hydroxyalkyl esters of skeleton carboxylic acids, alkyl esters of acrylic acid or methacrylic acid, etc.
The β-monoethylenically unsaturated monomer is used alone or as a mixture of two or more.

The phosphoric acid group-containing copolymer resin needs to contain a hydroxyl group in its molecule in order to undergo a crosslinking reaction with the polyester-modified vinyl resin.

Therefore, in order to balance the hydroxyl value of the polyester-modified vinyl resin, a hydroxyalkyl ester of α,β-monoethylenically unsaturated carboxylic acid is required as a type of α,β-monoethylenically unsaturated monomer. Use quantity.

The monomer is used in an amount of 1 to 30 weight percent, preferably 2 to 15 weight percent, in the monomer mixture constituting the phosphoric acid group-containing copolymer resin.

If the monomer is used in an amount exceeding 30 monomers, it becomes easy to gel during the copolymerization reaction, and the resulting phosphoric acid-containing copolymer resin has a high viscosity, and the crosslinking density with the polyester-modified vinyl resin is high. Too much, the flexibility of the coating film,
This is not preferable since water resistance etc. tend to decrease.

Specific examples of monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 3-hydroxypropyl (meth)acrylate.
-Hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (
meth)acrylate, neopentyl glycol mono(meth)acrylate, 3-butoxy-2-hydroxypropyl(meth)acrylate, 2-hydroxy-1-phenylethyl(meth)acrylate, polypropylene glycol mono(meth)acrylate, glycerin mono(meth)acrylate There are methacrylates and the like, and these may be used alone or as a mixture of two or more.

As one component of the phosphoric acid group-containing copolymer resin used in the present invention, 0.5
Use in the range of ~10 weight.

The monomer has the effect of improving the compatibility between the phosphoric acid group-containing copolymer resin and the polyester-modified vinyl resin and promoting the crosslinking reaction.

If the amount is less than 0.5 monomer, the effect will be weakened, and if it is more than 10 monomers, the performance of the cured coating film will deteriorate, which is not preferable.

Specific examples of the component include acrylic acid, methacrylic acid,
Examples include crotonic acid, itaconic acid, maleic acid, fumaric acid, etc., and these may be used alone or as a mixture of two or more.

As a raw material for the phosphoric acid group-containing copolymer resin used in the present invention, copolymerizable α,β-monoethylenically unsaturated monomers other than those mentioned above are reacted in a proportion of 70 to 90% by weight.

Specific examples of this component include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate,
acrylate, isopropyl (meth)acrylate, n
-Butyl (meth)acrylate, 5eC-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate
Acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate,
Alkyl esters of acrylic acid or methacrylic acid such as stearyl (meth)acrylate; other N,N'-dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, cyclohexyl (meth)acrylate, phenyl methacrylate, benzyl methacrylate, Examples thereof include fumaric acid dialkyl esters such as di-butyl fumarate, and monomers such as styrene, vinyltoluene, α-methylstyrene, (meth)acrylonitrile, and vinyl acetate.

The above monomers may be used alone or in an appropriate combination of two or more depending on the purpose and use of the coating composition.

The phosphoric acid group-containing copolymer resin of the present invention is produced by conventional solution polymerization.

As the polymerization solvent used in the solution polymerization method, the water-soluble or water-miscible solvents mentioned above are used.

Further, the polymerization initiator used is the above-mentioned organic peroxide or azo compound.

The chain transfer agents mentioned above can also be used to adjust the molecular weight.

Weight average molecular weight of the phosphoric acid group-containing copolymer resin of the present invention
, ooo~70,000, preferably 20,000~5
It is within the range of 0.000.

If the weight average molecular weight is less than s,ooo, the coating film performance will be insufficient, while if the weight average molecular weight is 70,000 or more, the smoothness will be impaired.

Furthermore, the hydroxyl value of the phosphoric acid group-containing copolymer resin of the present invention is 3 to 3.
A range of 150 is preferred.

Since the phosphoric acid group-containing copolymer resin of the present invention is highly reactive,
It tends to thicken under high temperatures such as summer.

In such cases, in order to further improve storage stability, the acid groups introduced into the phosphoric acid group-containing copolymer resin are neutralized with a basic compound to make the phosphoric acid group-containing copolymer resin more stable. It can be made of resin.

Examples of the basic compound include inorganic alkalis such as sodium hydroxide and potassium hydroxide; ammonia, monomethylamine, dimethylamine, trimethylamine, triethylamine, monoethylamine, mono-n-propylamine,
Water-soluble amines such as dimethyl-n-propylamine;
Monoethanolamine, jetanolamine, triethanolamine, N-methylethanolamine, N-aminoethylethanolamine, N-methylgetanolamine, monoisopropanolamine, diisopropanolamine, tripropanolamine, hydroxyl Examples include one type or a mixture of two or more types of water-soluble oxyamines such as amines.

In the case of neutralizing using such a compound, it includes neutralizing some or all of the acid groups in the phosphoric acid group-containing copolymer resin, and furthermore, it includes neutralizing some or all of the acid groups in the phosphoric acid group-containing copolymer resin. An excessive amount may be added in consideration of the stability of the composition or the performance of the coating film.

In the present invention, the polyester modified vinyl resin and the tric acid group-containing copolymer resin are used in a weight ratio of 15/85 to 9515, preferably 30/70 to 90/10.

If the polyester-modified vinyl resin exceeds 15% by weight within the above-mentioned range, one of the characteristics of the present invention, such as the excellent flexibility, pigment dispersibility, and coating film appearance, which the unsaturated polyester has, will be impaired.

On the other hand, if the amount of polyester-modified vinyl resin increases by 95 weight, the amount of phosphoric acid group-containing copolymer resin will inevitably decrease, which will not only reduce the temporary rust prevention effect that is a feature of the present invention, but also reduce corrosion resistance and water resistance. Deteriorate.

The softening temperature of the mixed resin particles of polyester-modified vinyl resin and phosphoric acid group-containing copolymer resin used in the present invention is preferably 30 to 100°C.

More preferably, the temperature is 40 to 80°C.

If the softening temperature is lower than 30°C, the storage stability of the paint tends to decrease, and if it is higher than 100°C, the smoothness of the coating film will be insufficient, which is not preferable.

In the present invention, if necessary, a known acid catalyst for promoting the crosslinking reaction between the polyester-modified vinyl resin and the phosphoric acid group-containing copolymer resin, an epoxy resin, a -(Z-D-ruce resin, an amino acid group-containing copolymer resin, etc.) It is also possible to use one or more other film-forming resins such as resin, polyester resin, and blocked isocyanate compound.

Next, a method for producing the water-dispersed thermosetting coating composition of the present invention will be explained.

As a production method, the usual mechanical grinding method used in the production of conventional powder coatings and slurry coatings can also be applied, but if the softening point is low, the adhesiveness of the resin composition is too thick and the powder It becomes difficult to convert into

Therefore, the water-dispersed thermosetting coating composition of the present invention can be advantageously produced by a special method as described below.

First, a predetermined amount of the polyester-modified vinyl resin and phosphoric acid group-containing copolymer resin are mixed with a basic compound that neutralizes some or all of the acid groups in the phosphoric acid group-containing copolymer resin, if necessary. The resin composition and, if necessary, a curing catalyst, other coating film-forming resins, etc. are dissolved in the water-soluble solvent to obtain a resin solution, and if necessary, a pigment is added and kneaded and dispersed to obtain a pigment dispersion.

This resin solution or pigment dispersion is emulsified into fine particles in water in an amount that dissolves all of the water-soluble or water-miscible solvent contained therein, and the solvent in the emulsified fine particles is extracted into the water. Resin particles are obtained.

The resin particles are separated from the water-solvent mixture by p-filtration or centrifugation, and if necessary, water washing and separation are repeated a necessary number of times to obtain resin particles in the form of a slurry or a water-containing cake.

In this way, preferably the average particle diameter is 1 to 200
Resin particles between μ are obtained.

Furthermore, after adding a surfactant and/or a thickener and water to the resin particles in the form of a slurry or a water-containing cake, the particles are dispersed using a conventional method such as a sand mill, a ball mill, a disperser, a Sussmeyer mill, etc. Pulverize the resin particles with a Centor Mill etc. to an average particle size of approximately 1 to 5.
Adjust between 0μ.

The thus obtained resin particles of the present invention contain an unsaturated polyester resin and a crosslinkable copolymer resin in - particles.

In other words, each particle necessarily contains groups that react with each other when heated, that is, a hydroxyl group and an ado group.

Therefore, when the composition of the present invention is heated, a coating film having excellent performance can be obtained through crosslinking in the resin particles and crosslinking reaction between the resin particles.

The water-dispersed thermosetting coating composition of the present invention preferably contains the resin particles dispersed in the form of fine particles having an average particle diameter of 1 to 50 μm.

If the average particle diameter is smaller than 1 μm, the cohesiveness of the particles increases, and properties similar to those of water-soluble paints, such as easy foaming during film formation by heating, are undesirable.

On the other hand, if it is larger than 50μ, the resin particles tend to precipitate and aggregate during storage, making it impossible to obtain a smooth coating surface, which is not preferable.

In particular, resin particles having an average particle diameter of 5 to 30 μm are suitable for the present invention because they form a coating material that has excellent storage stability and provides a smooth coating film without foaming.

The composition of the present invention may also contain, if necessary, a curing catalyst, organic and inorganic coloring and extender pigments commonly used in paints, a temporary rust preventive agent, a flow aid, an antifoaming agent, an anti-settling agent, and a fungicide. It may contain additives such as agents, preservatives, and other water-soluble resins, film-forming resins such as hydrosils, emulsion resins, and the like.

As mentioned above, since the softening temperature of the resin particles is preferably 30 to 100°C, it is preferable that components such as pigments that do not melt at the heating film forming temperature in the paint are added to the resin particles in an amount of 50% by weight or less. .

As the surfactant used in the present invention, known surfactants such as nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants can be used. For example, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alcohol ether, chrycerin fatty acid ester, propylene glycol fatty acid ester, polyoxyethylene castor oil derivative, polyoxyethylene Alkyl phenyl ethers, alkyl phosphate esters, polyoxyethylene phosphate esters, anionic surfactants include alkyl sulfate ester salts, polyoxyethylene alkyl ether sulfate ester salts, alkyl sulfosuccinates, N
-As the acyl sarcosine salt and cationic surfactant, quaternary ammonium salts, pyridinium salts, etc. can be used.

Nonionic surfactants are preferred from the viewpoint of dispersion stability of resin particles and coating film performance, and those with an HLB of 8 to 18 are particularly preferred.

Further, as the above-mentioned thickener used in place of or in combination with these surfactants, those conventionally used in water-based resin paints can be used.

These include, for example, cellulose-based water-soluble resins such as methyl cellulose, ethyl cellulose, and hydroxyethyl cellulose; polyvinyl alcohol; polyethylene-based water-soluble resins such as polyethylene glycol ether and polyethylene oxide; methyl vinyl ether maleic anhydride copolymer, and ethylene maleic anhydride. Water-soluble resins based on maleic anhydride copolymers such as copolymers and styrene-maleic anhydride copolymers; ammonium, amine salts and sodium salts of acrylic acid polymers, bentonite, polyvinylpyrrolidone, alginates, polyacrylamide and their Examples include partially hydrolyzed products, naturally occurring water-soluble resins such as casein and gelatin.

The above-mentioned surfactant and/or thickener is added in an amount of 0.01 to 1.0% by weight based on the fine powder resin particles.

If the amount added is less than 0.01% by weight, storage stability, painting workability, etc. will deteriorate, and 1. If the amount exceeds the weight ratio of O, the smoothness, water resistance, etc. of the coating film will deteriorate, making it unsuitable for the present invention.

Among the above-mentioned thickeners, amine salts of carboxyl group-containing acrylic copolymers are particularly suitable for the present invention because they become water-insoluble after heating the coating film due to elimination of amines and do not reduce the water resistance of the coating film. be.

The mixing ratio of water and fine powder resin particles in the coating composition of the present invention is preferably 90-30/10-70 by weight.

When the composition has fewer resin particles than the above mixing ratio, the solid content concentration of the paint is low and the viscosity is low, so the thickness of the normal coating film at one time, for example, 20 to 8
When applied to a thickness of 0μ, phenomena such as sagging occur in the coating film, and to avoid this, it is necessary to recoat several times, causing problems in painting workability.

On the other hand, if the amount of resin particles is greater than the above mixing ratio, it will be difficult to make the paint uniform by stirring, kneading, etc. during paint production, and the viscosity characteristics will not be suitable for various painting methods such as spray painting and electrostatic painting. Since it comes off, painting workability tends to be poor and practicality tends to decrease, which is not preferable.

The water-soluble or water-miscible solvent used in the production of the water-dispersed thermosetting coating composition of the present invention is the same as the polymerization solvent used in the solution polymerization method.

Further, the step of emulsifying the resin solution or pigment dispersion in water to form resin particles may include a method of dropping, injecting, or spraying the solution or dispersion into water under vigorous stirring, or a method of dropping, pouring, or spraying the solution or dispersion into water under vigorous stirring; A method such as mixing the solution or dispersion liquid with a line mixer can be used, but at this time, the stirring causes the temperature of the mixed liquid to rise, and the resin particles soften, causing the resin particles to coalesce or become integrated, and mixing to prevent them from becoming coarse. It is preferable to cool the liquid and maintain the liquid temperature at 30° C. or lower.

The water-dispersed thermosetting coating composition of the present invention may be applied using various well-known coating methods such as brush coating, dip coating, spray coating, electrostatic coating, curtain flow coating, shower coating, and roll coating. I can do it.

The conditions for heat curing after coating the coating composition vary depending on the content of crosslinkable functional groups in the composition, film thickness, etc.
A cured coating film can be obtained by heat treatment for 0 to 40 minutes.

The cured coating film thus obtained suppresses temporary rusting on the steel plate and has excellent adhesion to metal surfaces, corrosion resistance, and water resistance.

In addition, it combines the flexibility, pigment dispersibility, and excellent paint film appearance of polyester resin with the hardness and stain resistance of vinyl copolymer resin. It has excellent coating performance with no yellowing or bubbling.

The present invention will be explained below with reference to Examples.

Note that "part" or "part" means "part by weight" or "% by weight".

[Method for producing unsaturated polyester solution]

(1) Unsaturated polyester Al (hereinafter abbreviated as PE-1) After stirring, 32.6 parts of isophthalic acid and 18.6 parts of adipic acid were placed in a reaction vessel equipped with a thermometer, a cooling tube, and a nitrogen gas introduction tube.
7 parts, fumaric acid 3.0 parts, neopentyl glycol 2
9.0 parts and 16.7 parts of trimethylolpropane were charged and reacted at 22.5°C for about 8 hours in a nitrogen gas atmosphere to obtain an acid value of 15.1, a hydroxyl value of 155, and a weight average molecular weight of 6.700. was gotten.

This was diluted with methyl ethyl ketone to a non-volatile content of 60 parts to give PE-1.

(2) Unsaturated polyester scrap 2 (hereinafter abbreviated as PE-2) In a reaction vessel similar to that in which PE-1 was synthesized, 32.3 parts of isophthalic acid, 15.1 parts of adipic acid, and 77-JLi were added.
3.0 parts of acid, 22.9 parts of neopentyl glycol, 17.4 parts of trimethylolpropane, and 9.3 parts of Cardular E (trade name manufactured by Shell Chemical) were charged and reacted at 225°C for about 8 hours under a nitrogen gas atmosphere. The acid value was 16.2.
A product with a hydroxyl value of 166 and a weight average molecular weight of 4,200 was obtained.

This was diluted with methyl ethyl ketone to a non-volatile content of 60 parts to give PE-2.

(3) Unsaturated polyester, 463 (hereinafter abbreviated as PE-3) Using 32.6 parts of ortho-phthalic anhydride instead of 32.6 parts of isophthalic acid in PE-1, 225 After reacting at a temperature of about 6 hours, a product having an acid value of 45, a hydroxyl value of 158, and a weight average molecular weight of 2,450 was obtained.

This was diluted with methyl ethyl ketone to a non-volatile content of more than 60% to give PE-3.

(4) Unsaturated polyester A4 (hereinafter abbreviated as PE-4) In a reaction vessel similar to that in which PE-1 was synthesized, 36.0 parts of isophthalic acid, 11.5 parts of adipic acid, and 6 parts of 77-ethyl acid were added.
．． 0 parts, neopentyl glycol 34.0 parts, ■, 4-
12.5 parts of cyclohexane dimetatool was charged and reacted at 225°C for about 8 hours in a nitrogen gas atmosphere to produce an acid value of 7.
．． 5, hydroxyl value 94, and weight average molecular weight 3,950
I got something like this.

This was diluted with methyl ethyl ketone to a non-volatile content of 60% to give PE-4.

(5) Unsaturated polyester/165 (hereinafter abbreviated as PE-5) In a reaction vessel similar to that in which PE-1 was synthesized, 16.0 parts of isophthalic acid and 17 parts of methylhexahydrophthalic anhydride were added.
．． 5 parts, adipic acid 14.5 parts, fumaric acid 4.0 parts,
25.0 parts of neopentyl glycol, 13.0 parts of hydrogenated bisphenol A, and 1000 parts of trimethylolethane were charged and reacted at 225°C in a nitrogen gas atmosphere for about 8 hours to obtain an acid value of 1263, a hydroxyl value of 120, and a weight average. A product with a molecular weight of 9,300 was obtained.

This was diluted with methyl ethyl ketone to a non-volatile content of 60% to give PE-5.

[Method for producing polyester modified vinyl resin solution] (1)
Methyl ethyl ketone 30 was added to a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, a cooling tube, and a nitrogen gas introduction tube.
After adding 0 parts and raising the temperature to 80° C., the following monomer, unsaturated polyester and initiator mixture was added dropwise over 3 hours.

75 parts of methyl methacrylate, 140 parts of styrene, 165 parts of ethyl acrylate, 10 parts of 2-hydroxyethyl methacrylate, 10 parts of acrylic acid, 50 parts of N-n-butoxymethylacrylamide, 50 parts of the unsaturated polyester (PE-1). , 6 parts of abbisisobutyronitrile.

After dropping, add 1 part of abbisisobutyronitrile,
After raising the reaction temperature to 87°C, the reaction was carried out for 4 hours, and the acid value was 16.2, the hydroxyl value was 40.5, and the weight average molecular weight was 6.
1,500 and a non-volatile content of 57.5%, the softening temperature of the resin was approximately 66-68°C.

This was named PE-AV-1.

(2) Put 280 parts of methyl ethyl ketone into a reaction vessel similar to that in which PE-AV-1 was synthesized, and adjust the temperature to 80°C.
After raising the temperature to 100 ml, the following monomer, unsaturated polyester and initiator mixture was added dropwise over 3 hours.

60 parts of methyl methacrylate, 145 parts of styrene, 155 parts of ethyl acrylate, 5 parts of 2-hydroxyethyl methacrylate, 10 parts of acrylic acid, 50 parts of N-n-butoxymethylacrylamide, 75 parts of the unsaturated polyester (PE-2) , azobisisobutyronitrile 6
After dropping, 1 part of Abbisisobutyronitrile was added, the reaction temperature was raised to 87°C, and the reaction was carried out for 4 hours, resulting in an acid value of 17.4, a hydroxyl value of 67.0, and a weight average molecular weight. A resin solution of 135,100 and 58.1% non-volatile content was obtained, and the softening temperature of the resin was about 67-69°C.

This was named PE-AV-2.

(3) In polyester modified vinyl resin solution production (2), 300 parts of methyl ethyl ketone, 150 parts of ethyl acrylate, 10 parts of 2-hydroxyethyl methacrylate, 75 parts of N-n-butoxymethylacrylamide, and the unsaturated polyester The reaction was carried out in the same manner except that (PE-2) was changed to 50 parts, and the acid value was 16.
8, a resin solution with a hydroxyl value of 42.5, a weight average molecular weight of 72,100, and a nonvolatile content of 57.3% was obtained, and the softening temperature of the resin was about 64 to 67°C.

This was designated as PR-AV-3.

(4) Put 280 parts of methyl ethyl ketone into a reaction vessel similar to that in which PE-AV-1 was synthesized, and adjust the temperature to 80°C.
The following monomers, unsaturated polyester and starting mixture were added dropwise over 3 hours.

50 parts of methyl methacrylate, 135 parts of styrene, 145 parts of ethyl acrylate, 10 parts of 2-hydroxyethyl methacrylate, 10 parts of acrylic acid, 75 parts of N-n-butoxymethylacrylamide, 75 parts of the unsaturated polyester (PE-3) , 6 parts of azobisisobutyronitrile.

After the dropwise addition, 1 part of abbisisobutyronitrile was added, the reaction temperature was raised to 87°C, and the reaction was carried out for 4 hours to obtain an acid value of 15. A resin solution of 500 and 58.2% non-volatile content was obtained, and the softening temperature of the resin was approximately 63-65°C.

This was designated as PEAV-4.

(5) Polyester modified vinyl resin solution production (1) The reaction was carried out in the same manner except that unsaturated polyester PE-1 was replaced with unsaturated Bossester PE-4. Weight average molecular weight 5
A resin solution of 2,000 and 59.3% non-volatile content was obtained, with a softening temperature of about 63-66°C.

This was named PE-AV-5.

(6) In production of polyester-modified vinyl resin solution (1), the unsaturated polyester PE-1 was replaced with unsaturated polyester PE-5, and the N-n-butoxymethylacrylamide was replaced with N-t-butoxymethylacrylamide. The reaction was carried out in the same manner, and the acid value was 16.2.
, a resin solution with a hydroxyl value of 32, a weight average molecular weight of 62,100, and a non-volatile content of 58.9% was obtained, and the softening temperature was approximately 6.
The temperature was 5-68°C.

This was named PE-AV-6.

(7) In polyester modified vinyl resin solution production (1), N-n-butoxymethylacrylamide is
-The reaction was carried out in the same manner except that butoxymethylacrylamide was used, and the acid value was 16.3 and the hydroxyl value was 3.
7. Weight average molecular weight 558.200 and non-volatile content 59
．． 0% resin solution is obtained, the softening temperature is about 64-67℃
Met.

This was named PE-AV-7.

[Method for producing phosphoric acid group-containing copolymer resin solution] (1)
340 parts of methyl ethyl ketone was placed in a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, a cooling tube, and a nitrogen gas introduction tube, and after the temperature was raised to 80°C, the following monomer and initiator mixture was added dropwise over 3 hours. did.

Methyl methacrylate-t-190 parts, styrene 80 parts,
21Q parts of ethyl acrylate, 110 parts of 2-hydroxyethyl methacrylate, 5 parts of acidophosphoxyethyl methacrylate, 5 parts of acrylic acid, 10 parts of azobisisobutyronitrile.

After the dropwise addition, 1.5 parts of azobisisobutyronitrile was added, the reaction temperature was raised to 87°C, and the reaction was carried out for 4 hours, resulting in an acid value of 11.4, a hydroxyl value of 10, and a weight average molecular weight of 25.
,000 and a non-volatile content of 59.0%, the softening temperature of the resin was about 71-73°C.

PV-1 was obtained by adding 2/3 mole of triethylamine to the acid value of the resin solution to neutralize it.

(2) 340 parts of methyl ethyl ketone was placed in a reaction vessel similar to that in which PV-1 was synthesized, and after raising the temperature to 80°C, the following monomer and initiator mixture was added dropwise over 3 hours.

190 parts of methyl methacrylate, 70 parts of styrene, 215 parts of ethyl acrylate, 10 parts of 2-hydroxyethyl methacrylate, 10 parts of acidophosphoxyethyl methacrylate, 5 parts of acrylic acid, 10 parts of abisisobutyroni l-IJ .

After the dropwise addition, 1.5 parts of azobisisobutyronide IJ was added, the reaction temperature was raised to 87°C, and the reaction was carried out for 4 hours, resulting in an acid value of 13.7, a hydroxyl value of 9.5, and a weight of A resin solution having an average molecular weight of 30,800 and a non-volatile content of 59.0% was obtained, and the softening temperature of the resin was about 72-75°C.

PV-2 was obtained by adding 2/3 mole of triethylamine to the acid value of the resin solution to neutralize it.

(3) Production of phosphoric acid group-containing copolymer resin solution (2) The reaction was carried out in the same manner except that 200 parts of ethyl acrylate and 25 parts of acidophosphoxyethyl methacrylate were used, and the acid value was 28.8. , hydroxyl value 9.
1. Weight average molecular weight 31.100 and non-volatile content 60.
A 1% resin solution is obtained, and the softening temperature of the resin is approximately 73~
The temperature was 76°C.

PV-3 was obtained by adding 3/4 molar triethylamine to the acid value of the resin solution to neutralize it.

(4) 750 parts of methyl ethyl ketone was placed in a reaction vessel similar to the one in which the PV-1 was synthesized, and after raising the temperature to 80°C, the following monomer and initiator mixture was added dropwise over 3 hours.

190 parts of methyl methacrylate, 55 parts of styrene, 195 parts of ethyl acrylate, 15 parts of 2-hydroxyethyl methacrylate, 40 parts of acidophosphoxyethyl methacrylate, 5 parts of acrylic acid, 10 parts of abisisobutyronitrile.

After the dropwise addition, 1.5 parts of azobisisobutyronitrile was added, the reaction temperature was raised to 87°C, and the reaction was carried out for 4 hours, resulting in an acid value of 31.6, a hydroxyl value of 15, and a weight average molecular weight of 22. , 500 and a non-volatile content of 39.5%, the softening temperature of the resin was approximately 73-76°C.

PV-4 was obtained by adding 3 parts and 4 moles of triethylamine to the acid value of the resin solution to neutralize it.

(5) Production of phosphoric acid group-containing copolymer resin solution (1) The reaction was carried out in the same manner except that acidophosphoxyethyl methacrylate was replaced with acidiophosphoxyethyl acrylate, and the acid value was 12.8. value 10
, weight average molecular weight 28.100 and non-volatile content 59.3
% resin solution was obtained with a softening temperature of about 70-73°C.

PV-5 was obtained by adding 2 parts and 3 moles of triethylamine to the acid value of the previous resin solution to neutralize it.

Example 1 12 parts of titanium dioxide and 4.5 parts of methyl ethyl ketone were added to 24 parts of the resin solution (PE-AV-1,), and the mixture was kneaded and dispersed in a pot mill to a size of 10μ or less (measured with a grain gauge; the same applies hereinafter). , resin solution (PE-AY-1) 51
1 part, 10 parts of resin/solution (PV-4), and 3.5 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.

This was dropped into 2000 parts of water at a water temperature of 15° C. under high speed stirring to emulsify the pigment dispersion and extract the solvent into the water to form resin particles.

After that, p-filtration and water washing were repeated, and the average particle size was approximately 10.
A water-containing cake of resin particles with a particle size of 0μ and a water content of about 50% was obtained.

Add 100 parts of this water-containing cake to a nonionic surfactant 40% aqueous solution (trade name Emulgen 930, manufactured by Kao Atlas Co., Ltd.).
HLB 1 al ) 0.3 parts 2.0 parts of an aqueous solution of an alkali salt thickener 10 of an acrylic acid copolymer was added, and the resin particles were finely ground by dispersion kneading with a sand mill to obtain an average particle size of 15 μm. A slurry paint having a pH of 7.7 was obtained.

Example 2 To 24 parts of resin solution (PE-AV-2), 12 parts of titanium dioxide, 0.5 parts of flow aid (trade name: Modaflow, manufactured by Monsanto), and 4.0 parts of methyl ethyl ketone were added.
After kneading and dispersing to 10μ or less with a sand mill, the resin solution (PE
-AV-2), 16 parts of the resin solution (PV-3), and 3.5 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.

This was dropped into 2000 parts of water at a water temperature of 15° C. under high speed stirring to emulsify the pigment dispersion and extract the solvent into the water to form resin particles.

After that, passing through and washing with water were repeated, and the average particle size was approximately 10.
A resin water-containing cake with a water content of about 500 μl) was obtained.

Add 100 parts of this water-containing cake to a nonionic surfactant 40% aqueous solution (trade name Emulgen 930, manufactured by Kao Atlas Co., Ltd.).
Add 0.3 parts of HLB 15.1) and 2.0 parts of an aqueous solution of alkali salt thickening and cutting 10 of an acrylic acid copolymer, disperse and knead with a sand mill to finely pulverize the resin particles, and adjust the average particle size. A slurry paint of 15μ and pH 7.5 was obtained.

Example 3 1 part of titanium dioxide was added to 24 parts of resin solution (PE-AV-3).
After adding 2 parts of methyl ethyl ketone and 4.5 parts of methyl ethyl ketone, kneading and dispersing with a ball mill to a size of 10μ or less, the resin solution (PE-AV-3
), 24 parts of resin solution ('PV-2), and 3.5 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.

This was sprayed into 3000 parts of water at a water temperature of 20° C. under high speed stirring to emulsify the pigment dispersion and extract the solvent into the water to form resin particles.

After that, passing through and washing with water were repeated, and the average particle size was 150.
A resin particle water-containing cake with a water content of about 50% was obtained.

To 100 parts of this water-containing cake were added 0.4 parts of a nonionic surfactant 40 aqueous solution (trade name Emulgen 910, Kao Atlas HLB 12.2) and 4.0 parts of a thickener (hydroxyethyl cellulose 5 aqueous solution), Dispersion and kneading are performed using a ball mill, and the resin particles are finely pulverized to an average particle size of 1.
A slurry paint of 6μ, p)I 7.8 was obtained.

Example 4 1 part of titanium dioxide was added to 24 parts of resin solution (PE-AV-4).
2 parts, 0.5 parts of flow aid (trade name: Modaflow, manufactured by Monsanto), and 40 parts of methyl ethyl ketone were mixed and dispersed in a sand mill to a size of 10μ or less, and then the resin solution (PE-AV
-4), 48 parts of resin solution (PV-1), and 3.5 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.

This was dropped into 200 parts of water at a water temperature of 15° C. under high speed stirring to emulsify the pigment dispersion and extract the solvent into the water to form resin particles.

After that, repeated mouth filtration and water rinsing were repeated to obtain an average particle diameter of 100.
A resin particle water-containing cake with a water content of 50% was obtained.

Add 100 parts of this water-containing cake to 50% aqueous solution of nonionic surfactant (trade name: Emaruan 935, manufactured by Kao Atlas Co., Ltd.,
HLB 17.5) 0.2 parts and 2.0 parts of a 10% aqueous solution of an alkali salt thickener of an acrylic acid copolymer were added.
The resin particles were dispersed and kneaded in a sand mill to be finely pulverized to obtain a slurry-like paint having an average particle diameter of 14 μm and a pH of 7.7.

Example 5 In Example 4, the total blending amount of the resin solution (PE-AV-4) was increased from 32 parts to 40 parts, and the resin solution (PV-1) was changed to the resin solution (PV-2) (C@kae). A slurry-like paint having an average resin particle diameter of 15 μm and a pH of 7.6 was obtained in the same manner except that the blending amount was changed from 48 parts to 40 parts.

Example 6 In Example 1, except that the resin solution (PE-AV-1) was replaced with the resin solution (PE-AV-5) and the resin solution (PV-4) was replaced with the resin solution (PV-1). A slurry paint having an average particle diameter of 17 μm and a pH of 7.4 was obtained in the same manner.

Example 7 In Example 1, the resin solution (PE-AV-1) was replaced with a resin solution (PE-AV-6), and the resin solution (PV-4) was replaced with a resin solution (PV-2), and all other changes were made. In the same manner, a slurry paint having an average particle diameter of 15 μm and a pH of 7° 7.6 was obtained.

Example 8 In Example 1, except that the resin solution (PE-AV-1) was replaced with a resin solution (PE-AV-7) and the resin solution (PV-4) was replaced with a resin solution (PV-5). In the same manner, a slurry paint having an average particle size of 15 μm and a pH of 7.8 was obtained.

[Comparative Example 1] Seven polymers obtained by removing the unsaturated polyester for modification (PE-1) and N-n-butoxymethylacrylamide from the composition of the polyester modified vinyl) L' resin solution PE-AV-1 used in Example 1. The reaction was carried out in the same manner as in polyester modified vinyl resin solution production (1) except for the composition, and the acid value was 12.3 and the hydroxyl value was 27 (weight average molecular weight 17.5).
00) and a resin solution with a nonvolatile content of 58.4% was obtained.

To 24 parts of the resin solution, 12 parts of titanium dioxide and 4.5 parts of methyl ethyl ketone were added, and after kneading and dispersing in a sand mill to a size of 10μ or less, 44 parts of the resin solution and an average degree of condensation of 2.
5. 12 parts of a 60% methyl ethyl ketone solution of a butylated methylol melamine resin with a degree of etherification of 2.5 and a water-soluble component of 1% or less and 3.5 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.

The following steps were carried out in the same manner as in Example 1, with an average particle size of 15 μm and p
A slurry paint of H7.5 was obtained.

[Comparative Example 2] Polyester modified vinyl resin solution used in Example 3 (
From the composition of PE-AV-3), unsaturated polyester (PE-AV-3)
-2) and N-butoxymethylacrylamide, except for the monomer composition, the reaction was carried out in the same manner as in polyester-modified vinyl resin solution production (3). Average molecular weight 16,20
0) and a resin solution with a nonvolatile content of 59.1% was obtained.

To 24 parts of the resin solution, 12 parts of titanium dioxide and 4.5 parts of methyl ethyl ketone were added, and after kneading and dispersing in a ball mill to a size of 10μ or less, 48 parts of the resin solution and a blocked isocyanate resin (trade name: Fulleran Ue 6109, manufactured by Bayer AG) were added. ), 0.5 parts of dibutyltin dilaurate (dissociation catalyst), and 3 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.

The following steps were carried out in the same manner as in Example 3, with an average particle size of 15 μm and p
A slurry paint of H7.3 was obtained.

[Comparative Example 3] Polyester modified vinyl resin solution used in Example 1 (
The reaction was carried out in the same manner as in polyester-modified vinyl resin solution production (1) except for the monomer composition excluding the unsaturated polyester for modification (PE-1) from the composition of PE-AV-1), and the acid value was 13.6. A resin solution with a hydroxyl value of 30.5, a weight average molecular weight of 41,000, and a nonvolatile content of 58.7% was obtained.

To 24 parts of the resin solution, 12 parts of titanium dioxide and 4.5 parts of methyl ethyl ketone were added, and after kneading and dispersing in a ball mill to a size of 10 μm or less, 56 parts of the resin solution and 3.5 parts of methyl ethyl ketone were added, and the mixture was stirred and mixed uniformly. It was made into a pigment dispersion liquid.

The following steps were carried out in the same manner as in Example 1, with an average particle size of 15 μm and p
A slurry paint of H7.4 was obtained.

[Comparative Example 4] 12 parts of titanium dioxide and 4.5 parts of methyl ethyl ketone were added to 24 parts of the polyester modified vinyl resin solution prepared as follows, and after kneading and dispersing, phosphoric acid groups prepared as below were added. Example 1 was carried out in the same manner as in Example 1, except that 56 parts of a resin solution containing 3.5 parts of methyl ethyl ketone and 3.5 parts of methyl ethyl ketone were added and mixed with stirring to obtain a uniform pigment dispersion.
A slurry paint having a pH of 7.5 was obtained.

[Method for producing polyester modified vinyl resin solution] The above P
270 parts of methyl ethyl ketone was placed in a reaction vessel similar to that in which E-AV-1 was synthesized, and the temperature was raised to 80°C, and then the following monomer, unsaturated polyester, and initiator mixture was added dropwise over 3 hours.

200 parts of methyl methacrylate, 1 part of ethyl acrylate
50 parts, 45 parts of 2-hydroxyethyl methacrylate,
5 parts of acrylic acid, the unsaturated polyester (PE-1H
oo part, 6 parts of azobisisobutyronide IJ.

After dropping, add 1 part of abbisisobutyronitrile,
After raising the reaction temperature to 87°C, the reaction was carried out for 4 hours, and the acid value was 11.6, the hydroxyl value was 110, and the weight average molecular weight was 3.
1.000. A resin solution with a nonvolatile content of 62.0% was obtained, and the softening temperature of the resin was about 66-68°C.

[Method for producing a resin solution containing no phosphoric acid group] The above pv
340 parts of methyl ethyl ketone was placed in a reaction vessel similar to that in which -i was synthesized, and the temperature was raised to 80° C., and then the following 7-mer and initiator mixture was added dropwise over 3 hours.

50 parts of methyl methacrylate, 150 parts of styrene, 165 parts of ethyl acrylate, 125 parts of N-n-butoxymethylacrylamide, 10 parts of acrylic acid, 10 parts of azobisisobutyronitrile.

After the dropwise addition was completed, 1.5 parts of azobisisobutyroni (IJ) was added, the reaction temperature was raised to 87°C, and the reaction was carried out for 4 hours. A 58-4% resin solution was obtained, and the softening temperature of the resin was about 73-75°C.

The slurry paint prepared in each of the above examples and comparative examples was spray-painted onto a polished mild steel plate, set for 5 minutes, preheated at 90°C for 10 minutes, and dried by heating at each predetermined temperature to achieve a film thickness. A coating of approximately 35μ was formed.

Table 1 shows the heating drying conditions and physical property test results for the coating film.

Claims (1)

[Claims] 1 (A) (i) α, β- of i to 10 weight ratios
Acid value 50 or less, hydroxyl value 50-250, weight average molecular weight 2,000, containing unsaturated dicarboxylic acid as one of the constituent components
~20,000 unsaturated polyesters
・・・・・・・・・2 to 40 weight staff and (ii) (
a) Hydroxy alkyl ester of α, β-monoethylenically unsaturated carboxylic acid 1 to 30 weight ratio (b) N-alkoxy of α, β-monoethylenically unsaturated carboxylic acid amide Methylated monomer・・・・・・・・・
5 to 30 weight ratio () → Copolymerizable α other than the above ①, ((b) and (BXi)) β-monoethylenically unsaturated monomer 60 to 90 weight Hydroxyl value 10-150 obtained by graft polymerization of a monomer mixture separated from 98-60% by weight
, acid value 3-40, weight average molecular weight 40,000-200
,000 polyester modified vinyl resin...
...15-95 weight factor (B) (i) Phosphoric acid group-containing α,β-monoethylenically unsaturated monomer ...
...0.01-10 weight factor (1i) α, β
-Monoethylenically unsaturated carboxylic acid...
Q, 5-10 weight ratio (iii) Hydroxyalkyl ester of α,β-monoethylenically unsaturated carboxylic acid 1-30 weight ratio (IV) Previous statement (ii) (b) , (BX i
), (BXii) and (B) (111) copolymerizable α, β-monoethylene unsaturated monomers
......Weight average molecular weight s, ooo obtained from a monomer mixture ranging from 70 to 90 weight
~70,000 phosphate group-containing copolymer resin ・
... Fine powder thermosetting resin particles consisting of 85 to 5 weight percent, a surfactant and/or thickener having a weight range of 0.01 to 1.0 weight relative to the particles, and a required amount of water.A water-dispersible thermosetting coating composition with excellent temporary rust prevention properties.