JPH07268272A - Improved aqueous dispersion composition - Google Patents

Abstract

PURPOSE:To obtain an aqueous dispersion composition capable of providing a coating film improved in stain, chemical and water resistances while maintaining good weatherability. CONSTITUTION:An aqueous dispersion composition containing, as the essential ingredients, an aqueous dispersion of a fluoroolefin copolymer having hydrazide groups and at least either an aqueous dispersion of a (meth)acrylic polymer having keto groups or an aqueous dispersion of a urethane polymer having keto groups.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an aqueous dispersion composition which gives a coating film having excellent weather resistance, stain resistance, water resistance and chemical resistance.

[0002]

2. Description of the Related Art Conventionally, a copolymer composed of a fluoroolefin, cyclohexyl vinyl ether and various other monomers is soluble in an organic solvent at room temperature, has a transparent and high gloss when used as a paint, and It is known to provide a coating film having excellent properties of a fluororesin such as high weather resistance, water / oil repellency, stain resistance, and non-adhesiveness (for example, Japanese Patent Laid-Open No. 55-44083). The usage is increasing in such fields.

On the other hand, since the use of organic solvents is being regulated from the viewpoint of air pollution in recent years, there is an increasing demand for water-based paints and powder paints that do not use organic solvents. Consideration for that is made,
It has been reported that those having no functional group can be produced by emulsion polymerization (JP-A-55-25411).

Also, a product obtained by emulsion-polymerizing a fluorine-containing copolymer having a hydroxyl group is disclosed in JP-A-57-34107.
It is described in JP-A-61-231044. However, in these methods, it was essential to use an emulsifier and a hydrophilic organic solvent together. In these methods, when either one or both of the emulsifier and the hydrophilic organic solvent are not used, an aqueous dispersion cannot be obtained, or even if an aqueous dispersion is obtained, the mechanical and chemical stability is extremely high. Poorly, there was a problem that aggregation and sedimentation occurred during storage.

As a solution to this problem, an aqueous dispersion in which a fluorine-containing copolymer containing a fluoroolefin-based polymerized unit and a macromonomer-containing polymerized unit having a hydrophilic site as essential constituents is dispersed in water. A liquid has been proposed (JP-A-2-225550). This aqueous dispersion has excellent film-forming properties and good mechanical strength of the coating film, and can be produced without using an emulsifier or a hydrophilic organic solvent.

On the other hand, regardless of whether or not fluorine is contained,
It is known that the film-forming property of an aqueous resin dispersion is affected by the glass transition point of the resin. That is, when the atmospheric temperature is higher than the glass transition point of the resin, a continuous coating film is obtained, whereas when the atmospheric temperature is lower than the glass transition point of the resin, no coating film is formed.

Therefore, in the resin aqueous dispersion coating material, a method of lowering the film forming temperature by adding an organic solvent called a film forming aid to plasticize the resin is generally adopted. For on-site construction, it is necessary to form a film at 0 ° C, and if a large amount of film-forming auxiliary is used, the stability of the paint will decrease, and the drying will be delayed. It is difficult to raise the glass transition point. However, since the glass transition point of the resin cannot be increased, the surface hardness of the coating film is low and the stain resistance is not sufficient.

[0008]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems of the prior art. That is, it has excellent weather resistance, solvent resistance, stability as an aqueous dispersion, film-forming property, mechanical strength of the coating film, and improves the water resistance and stain resistance of the coating film. The purpose is to provide a new dispersion.

[0009]

The present invention has been made to solve the above-mentioned problems, and is an aqueous dispersion of a (meth) acrylic polymer containing a keto group or a urethane polymer containing a keto group. At least one of the aqueous dispersion,
It is intended to provide an aqueous dispersion composition containing a fluoroolefin-based copolymer aqueous dispersion containing a hydrazide group as an essential component. The (meth) acrylic polymer is a generic term for a methacrylic polymer and an acrylic polymer.

The hydrazide group of the fluoroolefin copolymer and the keto group of the (meth) acrylic polymer or the urethane polymer undergo a crosslinking reaction during the formation of the coating film, thereby improving the hardness of the coating film. Become. As a result, the stain resistance is improved, and at the same time, a coating film having excellent chemical resistance and adhesion can be obtained. Here, the keto group is a group composed of a carbonyl group and two carbons directly connected to the carbon.

The method for producing the fluoroolefin-based copolymer aqueous dispersion containing a hydrazide group is not particularly limited, but the fluoroolefin and the hydrazide group-containing unsaturated monomer and the general formula: XYZ (here X is a radically polymerizable unsaturated group, Y is a hydrophobic divalent linking group, and Z is a hydrophilic group). A copolymerizable monomer containing a hydrophilic macromonomer as an essential component is an aqueous solution. A preferable example is a method obtained by polymerizing in a medium.

In the present invention, fluoroolefins having about 2 to 4 carbon atoms such as vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, pentafluoropropylene and hexafluoropropylene are preferably used as the fluoroolefin. To be done. Perhalo olefins are particularly preferred.

As the hydrazide group-containing unsaturated monomer, those having various structures can be used as long as they have a radically polymerizable unsaturated group and a hydrazide group in the molecule. Suitable examples include those obtained by reacting an unsaturated group-containing carboxylic acid such as crotonic acid, maleic acid, and undecenoic acid with hydrazine, a keto group-containing unsaturated monomer, adipic acid dihydrazide, sebacic acid dihydrazide, and isophthalic acid dihydrazide. Reacted with dicarboxylic acid dihydrazide such as, hydroxyl group-containing unsaturated monomers such as hydroxybutyl vinyl ether and hydroxyallyl vinyl ether, after reacting polyisocyanate such as hexamethylene diisocyanate, toluene diisocyanate, the remaining isocyanate groups To which hydrazine is added.

General formula of the present invention: XYZ (where X is a radically polymerizable unsaturated group, Y is a hydrophobic divalent linking group,
Z is a hydrophilic group) The radically polymerizable unsaturated group X of the hydrophilic macromonomer represented by a vinyl group, an allyl group,
Examples thereof include propenyl group, isopropenyl group, acryloyl group, methacryloyl group and the like.

Since this unit is contained as an essential constituent component of the fluorocopolymer, not only the mechanical stability and chemical stability of the aqueous dispersion are improved, but also the film-forming property and the coating property of the coating film are improved. It also has excellent mechanical strength, and since it requires no or almost no emulsifying agent for stabilization, it has the characteristics of improving water resistance and stain resistance.

As the hydrophobic divalent linking group Y, a linear or branched hydrocarbon group, a polypropylene glycol group,
Aromatic groups and alicyclic groups such as cyclohexane ring and cyclododecane ring are effective. The more hydrophobic this linking group, the better the compatibility of the hydrophilic macromonomer with fluoroolefins and other copolymerizable monomers,
The reaction rate of the monomer is improved, and as a result, a fluorine-containing aqueous dispersion having excellent stability can be obtained without using an emulsifying agent for stabilization at all or hardly.

The hydrophilic group Z may be ionic, nonionic, amphoteric or a combination thereof, but when it is composed of only an ionic hydrophilic group, the chemical stability of the fluorinated aqueous dispersion will be improved. It is desirable to combine a macromonomer having a nonionic or amphoteric hydrophilic group because the decrease occurs. A nonionic hydrophilic group such as a polyoxyethylene group or a polyoxypropylene / polyoxyethylene group is particularly preferable from the viewpoint of strength of hydrophilicity and influence on physical properties of coating film.

The macromonomer means an oligomer or a low molecular weight polymer having a radically polymerizable unsaturated group at one end. That is, it is a compound having a radically polymerizable unsaturated group at one end and having at least two repeating units. Depending on the type of repeating unit, usually 100 or less repeating units are polymerizable,
It is preferably used in terms of water resistance.

Examples of the hydrophilic macromonomer include those represented by Chemical formula 1 and the like.

[0020]

[Chemical formula 1] (1) CH ₂ = CHOCH ₂ -cycloC ₆ H ₁₀ -CH ₂ O (CH ₂ CH ₂ O) _n H
(n is an integer from 2 to 40), (2) CH ₂ = CH ₂ OC ₄ H ₈ -O- (CH ₂ CH (CH ₃ ) O) _m -CH ₂ O (CH ₂ CH ₂ O) _n H ( m is an integer from 1 to 10, n is an integer from 2 to 40), (3) CH ₂ = CHO-C ₄ H ₈ -O- (CH ₂ CH ₂ O) _n H (n is an integer from 2 to 40)
.

Among them, those having a vinyl ether type structure are excellent in alternate copolymerizability with fluoroolefins,
The weather resistance of the copolymer coating film becomes good.

Such a hydrophilic macromonomer is produced by a method such as polymerizing formaldehyde or diol with vinyl ether or allyl ether having a hydroxyl group, or ring-opening polymerization of a compound having an alkylene oxide or a lactone ring. Is possible.

The macromonomer having a hydrophilic portion is a macromonomer having a chain in which a hydrophilic ethylenically unsaturated monomer is radically polymerized and having a radically polymerizable unsaturated group such as vinyl ether or allyl ether at the terminal. It may be.

Yamashita et al.
It can be produced by the method described in Lym. Bull., 5.335 (1981). That is, a polymer having a condensable functional group is produced by radically polymerizing an ethylenically unsaturated monomer having a hydrophilic group in the presence of an initiator having a condensable functional group and a chain transfer agent, and Examples include a method of reacting a functional group of this polymer with a compound such as glycidyl vinyl ether or glycidyl allyl ether to introduce a radically polymerizable unsaturated group at the terminal.

The ethylenically unsaturated monomer used for the production of this macromonomer includes acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, 2-methoxyethyl acrylate, 2-methoxyethyl methacrylate and diacetone acrylamide. , Hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, acrylic acid esters of polyhydric alcohols and methacrylic acid esters of polyhydric alcohols, and vinylpyrrolidone.

In addition to these, as a copolymerizable monomer,
Acrylamide and its derivatives, methacrylamide and its derivatives, N-methylol acrylamide derivatives, ethyl carbitol acrylate, methyl triglycol acrylate, 2-hydroxyethyl acryloyl phosphate, butoxyethyl acrylate and the like.

As an initiator used for the production of this macromonomer, 4,4′-azobis-4-cyanovaleric acid, 2,2′-azobis-2-amidinopropane hydrochloride, potassium persulfate, ammonium persulfate, Examples include azobisisobutyronitrile and benzoyl peroxide.

The fluorinated copolymer in the present invention may contain a polymerized unit containing a reactive group selected from a hydroxyl group, a carboxylic acid group and an epoxy group, in addition to the above units.

The polymerized units containing a hydroxyl group include a method of copolymerizing a monomer containing a hydroxyl group and a method of polymerizing a polymer to form a unit containing a hydroxyl group. Here, as the hydroxyl group-containing monomer, hydroxyalkyl vinyl ethers such as hydroxybutyl vinyl ether,
Examples thereof include hydroxyalkyl allyl ethers such as hydroxyethyl allyl ether, and hydroxyalkyl esters, hydroxyalkyl vinyl esters, and hydroxyalkyl allyl esters of acrylic acid or methacrylic acid such as hydroxyethyl acrylate and hydroxyethyl methacrylate.

As a method for polymerizing a polymer to form a unit containing a hydroxyl group, after copolymerizing hydrolyzable vinyl esters after polymerization,
An example is a method of forming a hydroxyl group by hydrolysis.

The polymerized unit containing a carboxylic acid group is formed by a method of copolymerizing a monomer containing a carboxylic acid group, and a polymer having a hydroxyl group is reacted with a dibasic acid anhydride to form a carboxylic acid group. There is a way to do it.

Examples of the carboxylic acid group-containing monomer include those shown in Chemical formula 2 and the like.

[0033]

CH ₂ = CHOR ¹ OCOR ² COOM, CH ₂ = CHCH ₂ -R ³ OCOR ⁴ COOM (R ¹ , R ³ are alkyl groups having 2 to 15 carbon atoms, R ² and R ⁴ are
A saturated or unsaturated linear or cyclic hydrocarbon group,
M is a compound containing hydrogen, an alkali metal or nitrogen. ).

The polymerized unit containing an epoxy group can be introduced by copolymerizing a monomer containing an epoxy group. Examples of the epoxy group-containing monomer include epoxy group-containing alkyl vinyl ethers such as glycidyl vinyl ether, epoxy group-containing alkyl allyl ethers such as glycidyl allyl ether, glycidyl acrylate and epoxy group-containing alkyl acrylates or methacrylates such as glycidyl methacrylate. , Etc. are exemplified.

The fluorine-containing copolymer in the present invention may contain, in addition to the above units, units based on a monomer copolymerizable therewith. Such monomers include ethylene, olefins such as propylene, vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether and cyclohexyl vinyl ether, vinyl esters such as butanoic acid vinyl ester and octanoic acid vinyl ester, styrene and vinyl. Vinyl compounds such as aromatic vinyl compounds such as toluene,
Examples thereof include allyl compounds such as ethyl allyl ether, acryloyl compounds such as butyl acrylate, and methacryloyl compounds such as ethyl methacrylate. In particular,
Olefins, vinyl ethers, vinyl esters,
Allyl ethers and allyl esters are preferably adopted.

Here, the olefins have 2 to 10 carbon atoms.
The vinyl ethers, vinyl esters, allyl ethers and allyl esters having a linear, branched or alicyclic alkyl group having about 2 to 15 carbon atoms are preferably adopted. .

In such a monomer, at least part of hydrogen bonded to carbon may be replaced with fluorine.

The fluoroolefin-based copolymer containing a hydrazide group in the present invention contains 20 to 80 mol% of polymerized units based on fluoroolefin and 0.1 to 50 mol% of units based on a hydrazide group-containing unsaturated monomer. It is preferable that the polymerized units based on the hydrophilic macromonomer are in a proportion of 0.1 to 25 mol%.

If the number of polymerized units based on fluoroolefin is too small, the weather resistance will not be sufficiently exhibited, and if it is too large, the water dispersibility will be extremely deteriorated, which is not preferable.
It is particularly preferably 30 to 70 mol%.

If the amount of the unit based on the hydrazide group-containing unsaturated monomer is too large, the storage stability in the coating state will be poor, and if it is too small, the degree of crosslinking will be insufficient and the desired stain resistance, solvent resistance, and coating strength will be obtained. Can't get Particularly, it is desirable that the amount is 1 to 30 mol%.

If the number of polymerized units based on the macromonomer having a hydrophilic site is too small, the water dispersibility will be extremely poor, and if it is too large, the weather resistance and water resistance of the coating film will be poor, such being undesirable. In particular, in order to achieve an extremely excellent effect of forming a film, it is preferable that this unit is contained in a proportion of 0.3 to 20 mol%.

In the present invention, an fluorinated aqueous dispersion having excellent dispersion stability can be obtained without using an emulsifying agent, but the use of an emulsifying agent is not hindered. As the nonionic emulsifier, an alkylphenol ethylene oxide adduct,
Examples thereof include higher alcohol ethylene oxide adducts, ethylene oxide and propylene oxide block copolymers, and the like. Examples of the anionic emulsifier include alkyl benzene sulfonate, alkyl naphthalene sulfonate, higher fatty acid salt, alkyl sulfate ester salt, alkyl ether sulfate ester salt, and phosphate ester salt.

The initiation of the emulsion polymerization in the present invention is carried out by adding a polymerization initiator in the same manner as the usual initiation of the emulsion polymerization.
As such a polymerization initiator, an ordinary radical initiator can be used, but a water-soluble initiator is preferably adopted, and specifically, a persulfate such as ammonium persulfate,
A redox initiator consisting of hydrogen peroxide or a combination of these with a reducing agent such as sodium hydrogen sulfite or sodium thiosulfate, and an inorganic start of a system in which a small amount of iron, ferrous salt, silver sulfate, etc. are made to coexist therewith. Examples thereof include agents, dibasic acid peroxides such as disuccinic acid peroxide and diglutaric acid peroxide, azobisisobutylamidine hydrochloride, and organic initiators such as azobisisobutyronitrile.

The amount of the polymerization initiator used can be appropriately changed depending on the type, emulsion polymerization conditions and the like, but normally 0.005 to 0.5 parts by weight is preferably employed per 100 parts by weight of the monomer to be emulsion polymerized. It Further, these polymerization initiators may be added all at once, or may be added in portions if necessary.

For the purpose of raising the pH of the emulsion, p
An H modifier may be used. As such a pH adjusting agent,
Examples thereof include inorganic bases such as sodium carbonate, potassium carbonate, sodium hydrogen orthophosphate, sodium thiosulfate and sodium tetraborate, and organic bases such as triethylamine, triethanolamine, dimethylethanolamine and diethylethanolamine.

The addition amount of the pH adjusting agent is usually an emulsion polymerization medium.
0.05 to 2 parts by weight per 100 parts by weight, preferably 0.1
~ 2 parts by weight. The higher the pH, the faster the polymerization rate.

The optimum value of the emulsion polymerization initiation temperature is appropriately selected depending on the kind of the polymerization initiator, but it is usually from 0 to 100.
C., preferably about 10 to 90.degree. C., is preferably adopted. The reaction pressure can be appropriately selected, but it is usually 1 to 100 kg / c.
It is desirable to use m ² , especially about ² to 50 kg / cm ² .

In such a production method, additives such as a monomer, water, an emulsifier, and an initiator may be charged as they are and polymerized as they are, but the stability of the dispersion can be improved by reducing the particle size of the dispersed particles. For the purpose of improving various properties such as gloss of the coating film, pre-emulsification may be performed using a stirrer such as a homogenizer before adding the polymerization initiator, and then the initiator may be added for polymerization. Further, the monomers may be added in a divided manner or continuously, in which case the monomer composition may be different.

In the present invention, at least one of a (meth) acrylic polymer aqueous dispersion containing a keto group and a urethane polymer aqueous dispersion containing a keto group must be contained.

As the (meth) acrylic polymer aqueous dispersion containing a keto group, those obtained by various methods can be used. For example, a (meth) acrylic acid ester and a monomer copolymerizable therewith can be used. And acetoacetic acid ester of hydroxyethyl acrylate, diacetone acrylamide,
It can be obtained by emulsion copolymerization with a keto group-containing monomer such as acrolein.

The production method of the urethane polymer aqueous dispersion containing a keto group is not limited, but when polyisocyanate such as hexamethylene diisocyanate or toluene diisocyanate and polyol such as polyethylene glycol or polypropylene glycol are polyadded with each other. , 4-hydroxy-2-butanone and the like, can be obtained by chain termination with a keto group-containing monool.

Examples of the keto group-containing unsaturated monomer include those represented by Chemical formula 3.

[0053]

Embedded image R ¹ HC = CR ² (CH ₂ ) _n -O- (C = O) _m- (CH ₂ ) _l- (O) _k- (C = O) _o
-(CH ₂ ) _p- (C = O)-(CH ₂ ) _q -CH ₃ (R ¹ = H, CH ₃ : R ² = H, CH ₃ : n = 0,1: m = 0,1: l = 0 to 20: k = 0,1: o = 0,
1: p = 1 to 20: q = 0 to 20), R ¹ HC = CR ² (CH ₂ ) _n -O- (C = O) _m -R ^3- (O) _k- (C = O) _o -(CH ₂ ) _p- (C =
O)-(CH ₂ ) _q -CH ₃ (R ¹ = H, CH ₃ : R ² = H, CH ₃ : R ³ is a divalent alicyclic hydrocarbon group: n =
0,1: m = 0,1: k = 0,1: o = 0,1: p = 1 to 20: q = 0 to 20), R ¹ HC = CR ² (C = O) _n- (O ) _m- (CH ₂ ) _l- (O) _k- (C = O) _o- (CH ₂ ) _p- (C =
O)-(CH ₂ ) _q -CH ₃ (R ¹ = H, CH ₃ : R ² = H, CH3: n = 0,1: m = 0,1: l = 0 to 20: k = 0,1 : o = 0,
1: p = 1 to 20: q = 0 to 20).

In particular, vinyl ether type and isopropenyl type copolymers have excellent copolymerizability with fluoroolefins, and a copolymer coating film having excellent weather resistance can be obtained. Such monomers are obtained by transesterification of acetoacetic acid ester or reaction of hydroxyl group-containing vinyl ether with diketene.

(Meth) acrylic polymer aqueous dispersion containing a keto group, urethane polymer aqueous dispersion containing a keto group, and fluoroolefin copolymer containing a hydrazide group in the aqueous dispersion composition. The mixing ratio of the aqueous dispersion is such that the molar ratio of the keto group / the hydrazide group in the aqueous dispersion composition is 1/10 to 10/1, preferably 1/5.
The ratio is about 5/1.

The aqueous dispersion of the present invention can be used as an aqueous coating as it is, but if necessary, a colorant, a plasticizer, an ultraviolet absorber, a leveling agent, an anti-cissing agent, an anti-burr agent, a curing agent. Etc. may be mixed.

Examples of the colorant include dyes, organic pigments and inorganic pigments. Examples of the plasticizer include conventionally known ones, for example, low molecular weight plasticizers such as dioctyl phthalate, high molecular weight plasticizers such as vinyl polymer plasticizers and polyester plasticizers. A pH adjuster may be added to improve the stability of the aqueous dispersion.

[0058]

EXAMPLES The present invention will be specifically described below with reference to synthesis examples and examples, but the present invention is not limited to the examples. In the following examples, the number of parts means part by weight unless otherwise specified.

[Synthesis Examples 1 to 3] Ethyl vinyl ether (EVE), cyclohexyl vinyl ether (CHVE), hydroxybutyl vinyl ether (H) having the composition shown in Table 1 were placed in a stainless steel autoclave having an internal volume of 200 ml.
BVE), a hydrazide group-containing monomer (HDVE-1,
HDVE-2), hydrophilic macromonomer (EOVE),
Ion-exchanged water 105.5 parts, potassium carbonate 0.22 parts,
Nonionic emulsifier (N-1110; manufactured by Nippon Emulsifier) 2.
2 parts, anionic emulsifier (sodium lauryl sulfate)
0.11 part, polymerization initiator (ammonium persulfate) 0.0
Charge 7 parts, cool with ice, pressurize nitrogen gas to 3.5 kg / cm ² and degas.

After repeating this pressure deaeration twice and deaeration to 10 mmHg to remove the dissolved air, chlorotrifluoroethylene (CTFE) was charged and reacted at 50 ° C. for 10 hours to contain a hydrazide group. A fluoroolefin copolymer aqueous dispersion was obtained. The abbreviations in Table 1 are as shown in Chemical formula 4.

[0061]

Embedded image HDVE-1: CH ₂ = CHO-C ₄ H ₈ -OC (= O) NH (CH ₂ ) _{6
NHC (= O) NHNH 2,} HDVE-2: CH 2 = CHO-C 4 H 8 -OC (= O) CH 2 C (CH 3) = NNHC (C
= O) C ₄ H ₈ C (= O) NHNH ₂ , EOVE: CH ₂ = CHOC ₄ H ₈ -O- (CH ₂ CH ₂ O) _n H, average molecular weight 5
20.

[Synthesis Example 4- (Meth) acrylic polymer aqueous dispersion] In a glass four-necked flask equipped with a reflux condenser and a stirrer, 100 parts of butyl acrylate, 100 parts of ethyl methacrylate and diacetone were placed. Acrylamide 10 parts, ion-exchanged water 210 parts, nonionic emulsifier (N-111
0: made by Nippon Emulsifier) 6 parts and an initiator (ammonium persulfate) 0.05 part were added, and the system was replaced with nitrogen, then 60
The temperature was raised to 0 ° C. and the reaction was carried out for 10 hours to obtain an aqueous dispersion of a keto group-containing (meth) acrylic copolymer.

[Synthesis Example 5-Urethane Polymer Aqueous Dispersion] In a glass four-necked flask equipped with a reflux condenser and a stirrer, 80 g of N-vinylpyrrolidone, 100 g of polyethylene glycol (average molecular weight 400), and hexamethylene were used. Diisocyanate 63g and 4-hydroxy-2-butanone 22g were added, and the reaction was carried out at 50 ° C for 2 hours. After cooling to room temperature, 264 g of ion-exchanged water was added and vigorously stirred to obtain a keto group-containing urethane polymer aqueous dispersion.

"Examples 1 to 3, Comparative Examples 1 to 3" The amounts of the fluorine-containing aqueous dispersions obtained above were shown in Table 2, 5.4 parts of a film-forming aid (Cs-12; manufactured by Chisso), A clear paint was prepared by adding 0.3 part of a thickener (Reobis CR; manufactured by Hoechst Synthetic), 0.6 part of an antifoaming agent (FS Antifoam 013B; manufactured by Dow Corning), and 10.3 parts of ion-exchanged water.

These paints were applied on an aluminum plate by air spraying so that the dry film thickness was 40 μm, and
It dried at 1 degreeC for 1 week, and obtained the test piece. The test pieces were tested for gel fraction, weather resistance, water resistance and solvent resistance, and stain resistance. The gel fraction was measured by using a clear film peeled from the obtained test piece at room temperature in THF (tetrahydrofuran).
It was immersed in the solution for 24 hours, the film was taken out, and the residue weight% after vacuum drying was set. The weather resistance was evaluated as x when the gloss was remarkably reduced after 3000 hours of the QUV test, and ◯ when the gloss was not significantly reduced.

The water resistance was evaluated by immersing the film in warm water at 60 ° C. for 1 week and then judging whether the coating film was blistered or peeled off. The solvent resistance was evaluated by performing a rubbing test with a cloth dipped in methyl ethyl ketone and examining the number of times the coating film was damaged. The stain resistance was exposed outdoors at 45 ° on the south side for 1 year, and the color difference between the storage plate and the water splash was 5 or less, and “x” was given.

[0067]

[Table 1]

[0068]

[Table 2]

[0069]

The aqueous dispersion composition of the present invention has weather resistance,
It gives a coating film excellent in stain resistance, water resistance and chemical resistance. The aqueous dispersion composition of the present invention having these excellent properties is extremely useful as a raw material for weather resistant aqueous coating materials. Further, the aqueous coating material using the aqueous dispersion composition of the present invention has no fear of problems such as solvent regulation and can be applied to a wide range of applications. For example, it is useful for coating inorganic exterior building materials such as glass, metal, and cement.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuko Kitahata 3-474 Tsukakoshi, Sachi-ku, Kawasaki-shi, Kanagawa 2 Asahi Glass Co., Ltd. Tamagawa Branch Office

Claims (4)

[Claims] 1. An aqueous dispersion of a (meth) acrylic polymer containing a keto group and an aqueous dispersion of a urethane polymer containing a keto group, and an aqueous fluoroolefin copolymer containing a hydrazide group. An aqueous dispersion composition containing a dispersion as an essential component. 2. At least one of a (meth) acrylic polymer aqueous dispersion containing a keto group and a urethane polymer aqueous dispersion containing a keto group in the aqueous dispersion composition, and a hydrazide group. The mixing ratio with the fluoroolefin copolymer aqueous dispersion is such that the molar ratio of the keto group / the hydrazide group in the aqueous dispersion composition is 1/10 to 10.
The composition of claim 1 in a ratio such that it is / 1. 3. A fluoroolefin-based copolymer aqueous dispersion (B) containing a hydrazide group comprises a fluoroolefin and a hydrazide group-containing unsaturated monomer and a general formula: X.
Copolymerizable with a hydrophilic macromonomer represented by -Y-Z (where X is a radically polymerizable unsaturated group, Y is a hydrophobic divalent linking group, and Z is a hydrophilic group) as an essential component The composition according to claim 1, which is obtained by polymerizing various monomers in an aqueous medium. 4. A copolymerization ratio of a fluoroolefin copolymer containing a hydrazide group is 20 to 80 mol% of a polymer unit based on a fluoroolefin, and a unit based on an unsaturated monomer containing a hydrazide group is 0.1 to 50 mol. % And 0.1 to 25 mol% polymerized sites based on hydrophilic macromonomer.