JP3004261B1 - Aqueous paint composition - Google Patents

Abstract

The present invention provides an aqueous coating composition which is stable in an emulsified state and can form a coating film having excellent weather resistance. SOLUTION: (I) An emulsifier-containing polymer obtained by polymerizing one or more monomers selected from the group consisting of a vinyl monomer and a diene monomer in the presence of an emulsifier; II) General formula (1): Wherein A is an alkylene group or the like, R ³ and R ⁴ are hydrogen atoms or the like, and R ¹ and R ² are groups (B): (Wherein, R ⁵ represents an alkylene group or the like, and R ⁶ and R ⁷ represent an alkyl group or the like). And a bisbenzotriazolylphenol compound represented by the following formula:

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an aqueous coating composition containing an ultraviolet absorbent.

[0002]

2. Description of the Related Art Conventionally, organic solvent-based paints containing a synthetic resin as a film-forming component have been used for the surface protection and appearance of molded articles made of at least one of various materials such as synthetic resins, woods and ceramics. Hereinafter, simply referred to as “solvent-based paint”) is widely used. However, solvent-based paints release large amounts of organic solvents into the atmosphere during the process of film formation, which may have a negative effect on workers and the environment. However, it is proceeding.

[0003] Generally, as a film-forming component of a water-based paint,
An emulsion polymer (also referred to as a synthetic resin emulsion) produced by polymerizing (emulsion polymerization) a monomer such as a vinyl acetate resin or an acrylic resin in an emulsified state is used. However, an aqueous paint using the emulsion polymer alone (ie, an emulsion paint)
The film is insufficient in the weather resistance of the formed film, and therefore, when used, for example, when exposed to ultraviolet rays, the film deteriorates and cracks, and the film deteriorates (discoloration, fading, etc.) There was a risk of doing. So, to prevent them,
It has been proposed to incorporate an ultraviolet absorber or the like into the water-based paint.

Examples of the ultraviolet absorber include benzophenone compounds, benzotriazole compounds, phenyl salicylate compounds and phenyl benzoate compounds (Japanese Patent Application Laid-Open No.
No. 6-127635), addition-type ultraviolet absorbers such as cyanoacrylate compounds, and the general formula (2):

[0005]

Embedded image [In the formula, X represents a hydrogen atom or a halogen atom. R ^a
Represents a hydrogen atom, a methyl group or a tertiary alkyl group having 4 to 6 carbon atoms. R ^b represents a linear or branched alkylene group having 2 to 10 carbon atoms. R ^c represents a hydrogen atom or a methyl group. A benzotriazole compound having a (meth) acryloyloxy group introduced therein (Japanese Unexamined Patent Publication No.
25555447, JP-A-5-271203, etc.) or the general formula (3):

[0006]

Embedded image [Wherein, Y is directly bonded: or an alkylene group having 1 to 6 carbon atoms, a group: —C (CH ₃ ) ₂ —, a group: —C (C
_{2 H 5) (CH 3)} -, group: -O- or a group: -NH-
Is shown. R ⁸ and R ¹⁰ are the same or different and each represents a hydroxyl group or a linear or branched hydroxyalkyl group having 1 to 12 carbon atoms. R ⁹ and R ¹¹ are the same or different and each represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom. And a reactive ultraviolet absorber having a reactive side chain, such as a bisbenzotriazolylphenol compound (JP-A-9-316060).

[0007]

However, most of the above-mentioned ultraviolet absorbers are crystalline, are hardly soluble in water or organic solvents, have poor dispersibility in an emulsified state, and are used as coating film forming components. Due to insufficient compatibility with the emulsion polymer, the water-based paint prepared by blending these ultraviolet absorbers generates a gel (aggregate) or separates liquid, and maintains a stable emulsified state. There was a problem that can not be.

Further, even if the above-mentioned ultraviolet absorbers are blended to prepare a practically usable (emulsified state is somewhat stable) water-based paint, these ultraviolet absorbers are not compatible with metal ions. Due to high reactivity (low metal ion resistance), the resulting coating film has a problem of browning when it comes in contact with a substance containing metal ions such as sodium ions.
An object of the present invention is to provide an aqueous coating composition which can form a coating film having a stable emulsified state and excellent weather resistance.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the following emulsifier-containing polymer described as (I) as a coating film-forming component has been added to the general formula (II). The water-based paint containing the ultraviolet absorbent represented by the formula (1) has a new fact that the emulsified state thereof is stable, and the obtained coating film has excellent weather resistance over a long period of time. The invention has been completed.

That is, the aqueous coating composition of the present invention comprises (I) ( meth) acrylic acid, (meth) acrylic acid ester
And (II) an emulsifier-containing polymer obtained by polymerizing one or more monomers selected from the group consisting of benzenes and aromatic vinyls in the presence of an emulsifier;

[0011]

Embedded image In the formulas, A represents a main styrene group. R ³ and R ⁴ are the same or different and each represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms,
It represents an aryl group, an alkoxy group having 1 to 4 carbon atoms or a halogen atom. R ¹ and R ² are the same or different,
Group (B):

[0012]

Embedded image (Wherein, R ⁵ is directly bonded or has 1 to 1 carbon atoms.
2 represents a linear or branched alkylene group. R ⁶ and R ⁷ are the same or different and each represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. m represents an integer of 1 to 20, and n represents an integer of 4 to 8. ). And a bisbenzotriazolylphenol compound represented by the following formula:

In the present invention, the bisbenzotriazolyl phenol compound represented by the above general formula (1) used as an ultraviolet absorber has a long-chain polyester group (B) in its molecule, and thus has an organic solvent. Since it is easily soluble in water and has excellent compatibility with the emulsifier-containing polymer, it has excellent dispersibility in an emulsified state.

Therefore, the aqueous coating composition of the present invention can maintain a very stable emulsified state without generating a gel or causing liquid separation. In addition, the bisbenzotriazolylphenol compound (1) has a structure in which benzotriazolylphenol is dimerized, and therefore has a higher molecular weight and a higher decomposition temperature than conventional UV absorbers, so that a coating film is formed. There is no risk of evaporation or decomposition during heating.

The bisbenzotriazolylphenol compound (1) has a structure in which benzotriazolylphenol is dimerized, so that it has a large ultraviolet absorbing capacity per unit weight and a smaller amount than conventional ultraviolet absorbers. Can add very high weather resistance to the water-based paint. Further, the bisbenzotriazolylphenol compound (1) has a relatively long molecular weight and a long-chain polyester (B) which can be integrated with a functional group of an emulsifier-containing polymer in the molecule. Therefore, there is no possibility of bleeding out easily from the coating film.

Accordingly, the coating film formed from the aqueous coating composition of the present invention has excellent long-term weather resistance. Further, the above bisbenzotriazolylphenol compound (1)
Has a structure in which one benzotriazolephenol in the same molecule serves as a bulky protective group for the phenolic hydroxyl group of the other benzotriazolephenol, thereby preventing complex formation with a metal ion.

Thus, the coating film formed from the aqueous coating composition of the present invention has excellent metal ion resistance and does not easily brown even when it comes into contact with a substance containing metal ions such as a cleaner.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The aqueous coating composition of the present invention comprises (I) an emulsifier-containing polymer as a coating film-forming component and (II) a bisbenzotriazolylphenol compound represented by the general formula (1) as an ultraviolet absorber. contains.

First, (I) an emulsifier-containing polymer as a coating film forming component will be described. Such emulsifier-containing polymers include ( meth) acrylic acid, (meth) acrylic acid
It is obtained from one or more monomers selected from the group consisting of steles and aromatic vinyls, and an emulsifier.
Known monomers can be used as these monomers, for example, acrylic acid, methacrylic acid; acrylic acid or methacrylic acid (these are referred to as (meth) acrylic acids) methyl, ethyl (meth) acrylate, propyl (meth) acrylate ,
Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate,
(Meth) acrylic esters such as glycidyl (meth) acrylate, polyethylene glycol mono (meth) acrylic acid, and polypropylene glycol mono (meth) acrylic acid; aromatic vinyls such as styrene and α-methylstyrene
Etc. kind, and the like.

[0020] These monomers, one each alone,
Alternatively, two or more kinds can be used in combination.
Among them, a combination of (meth) acrylic acid and (meth) acrylic acid esters, a combination of (meth) acrylic acid, (meth) acrylic acid esters, and aromatic vinyls are particularly preferable.

The emulsifier is not particularly limited, and various emulsifiers can be used. In particular, it is preferable to use an anionic emulsifier or a nonionic emulsifier. Known anionic emulsifiers can be used, such as alkyl sulfates, alkyl benzene sulfonates, alkyl diphenyl ether disulfonates, dialkyl sulfocasuccinates, polyoxyalkylene alkyl ether sulfates, and polyoxyalkylene aryls. Examples thereof include ether sulfates and polyoxyalkylenestyryl phenyl ether sulfates.

Among these anionic emulsifiers, polyoxyalkylenestyryl phenyl ether sulfate, alkyl diphenyl ether disulfonate, polyoxyalkylene aryl ether sulfate and the like are preferable, and polyoxyalkylene styryl phenyl ether sulfate and the like are particularly preferable. . As specific examples, for example, Newcol 271A, 271NH, 560SF, 520
SN, 707SF, 707SN, 723SF, 740S
Commercial products sold under trade names such as F, Antox MS-2N, and MS-NH4 (manufactured by Nippon Emulsifier Co., Ltd.) can be mentioned. Among these commercial products, Newcol 707
It is preferable to use SF, 707SN, 723SF, 740SF, or the like.

The above-mentioned anionic emulsifiers are used alone or in combination of two or more. On the other hand, as nonionic emulsifiers, for example, polyoxyethylene lauryl ether, polyoxyethylene dodecyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene styryl phenyl ether, etc. Oxyalkylene ethers; polyoxyalkylene esters such as polyoxyethylene sorbitan laurate and polyoxyethylene stearate;
Polyoxyethylene polyoxypropylene block or random copolymer, polyethylene bricol (meta)
And polyalkylene glycol esters such as acrylate.

Among these nonionic emulsifiers, polyoxyalkylene ethers are preferable, and polyoxyalkylene ethers having an HLB of 16 or more (particularly polyoxyethylene styryl phenyl ether) are particularly preferable.
For example, New Call 506, 512,
520, 723, 740, 780, 806, 809, 1
120, 1140, Antox MS-60, MA-
Commercial products sold under trade names such as 30, 50, 100, and 150 (manufactured by Nippon Emulsifier Co., Ltd.) are exemplified.

The above-mentioned nonionic emulsifiers can be used alone or in combination of two or more. In the present invention,
The above-mentioned anionic emulsifier and nonionic emulsifier can be used in combination. The amount of the emulsifier used for producing the emulsifier-containing polymer is not particularly limited.
It is preferable to use 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight based on 00 parts by weight.

[0026] The emulsifier-containing polymer, and an emulsifier, (menu
(T) acrylic acid, (meth) acrylic acid esters and
It can be obtained by subjecting a mixture with one or more monomers selected from the group consisting of aromatic vinyls to a known polymerization means. For example, according to emulsion polymerization, for example, in an inert solvent such as ion-exchanged water, (meth) acrylic acid,
One or more monomers selected from the group consisting of (meth) acrylates and aromatic vinyls, and an emulsifier (preferably an anionic emulsifier and / or a nonionic emulsifier) What is necessary is just to mix | blend a polymerization initiator with a mixture.

The polymerization initiator is not particularly limited as long as it is a known one used for emulsion polymerization. Examples thereof include persulfates such as potassium persulfate, sodium persulfate and ammonium persulfate, sodium perborate, potassium perborate, and persulfate. Perborates such as ammonium borate, hydrogen peroxide, 2,2′-azobis (2-amidinopropane) dihydrochloride,
An azo compound such as 2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide, the above peroxide and sodium sulfite, sodium thiosulfate, sulfuric acid
Redox polymerization initiators used in combination with a reducing agent such as iron and the like can be mentioned. Of these, persulfates are preferred.

At the time of polymerization, a protective colloid agent or the like can be used in combination. The reaction temperature is usually from room temperature to 10
The reaction time is 0 ° C., and the reaction time may be appropriately selected from a wide range according to the reaction temperature and the like, but may be generally about 3 to 20 hours. After completion of the reaction, an emulsion of the emulsifier-containing polymer can be obtained by performing a usual means such as neutralization.

The bisbenzotriazole compound (I) used as an ultraviolet absorber in the aqueous coating composition of the present invention will be described. In the above bisbenzotriazole phenol compound (I), A is methylene.

1 to 10 carbon atoms corresponding to R ⁶ and R ⁷
Examples of the alkyl group include a linear or branched alkyl group such as methyl, ethyl, propyl, iso-propyl, butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl.
Among these, methyl, ethyl, propyl, iso-
A linear or branched alkyl group having about 1 to 3 carbon atoms, such as propyl, is preferred. Among the groups corresponding to R ⁶ and R ⁷ , a hydrogen atom is particularly preferred.

Examples of the linear or branched alkylene group having 1 to 12 carbon atoms corresponding to R ⁵ include, in addition to the above-mentioned alkylene groups having 1 to 6 carbon atoms, heptamethylene,
Octamethylene, nonamethylene, decamethylene, undecamethylene, dodecamethylene and the like can be mentioned. Among the group corresponding to R ⁵ is preferably a linear alkylene group having 1 to 12 carbon atoms.

In the long-chain polyester (B), m is 1
-20, preferably an integer of 2-10. The bisbenzotriazolylphenol compound (1) is, for example, a bisbenzotriazolylphenol compound (3) in addition to the general formula (4):

[0033]

Embedded image Wherein R ⁶ , R ⁷ and n are the same as above. And the ring-opening addition polymerization of the lactone represented by the formula (1).

As the bisbenzotriazolylphenol compound (3), known compounds described in JP-A-9-316060 can be used. Specific examples thereof include, for example, 2,2′-methylenebis [6- (2H-
1,2,3-benzotriazol-2-yl) -4-
(2-hydroxyethyl) phenol], 2,2′-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (3-hydroxypropyl) phenol], 2,2 ′ -Methylenebis [6- (2H-
1,2,3-benzotriazol-2-yl) -4-
(4-hydroxybutyl) phenol].

Known lactones (4) can be used, for example, ε-caprolactone, trimethyl-
ε-caprolactone, monomethyl-ε-caprolactone, γ-butyrolactone, δ-valerolactone and the like. The ring-opening addition polymerization of the lactone (4) can be carried out according to a known method. For example, the bisbenzotriazolylphenol compound (3) may be reacted with the lactone (4) in the presence of a ring-opening addition polymerization catalyst.

Examples of the catalyst include organic titanium compounds such as tetraethyl titanate, tetrabutyl titanate and tetrapropyl titanate; and organic tin compounds such as stannous octylate, dibutyltin oxide, dibutyltin laurate, and mono-n-butyltin fatty acid salts. Compounds, stannous chloride, stannous bromide, stannous halides such as stannous iodide and the like.

The amount of the catalyst used is usually 0.1 to 10 based on the bisbenzotriazolylphenol compound (3).
The concentration may be about 000 ppm, preferably about 1 to 5000 ppm. The above ring-opening addition polymerization reaction is usually 90 to
The reaction may be performed at a temperature of about 240 ° C., preferably about 100 to 220 ° C., for about 3 to 24 hours, preferably about 4 to 10 hours.

Specific examples of the bisbenzotriazolylphenol compound (1) thus obtained include, for example, 2,2'-methylenebis [6- (2H-1,2,3
-Benzotriazol-2-yl) -4- (glycoloyloxyethyl) phenol], 2,2'-methylenebis [6- (2H-1,2,3-benzotriazol-2)
-Yl) -4- (3-hydroxypropanoyloxyethyl) phenol], 2,2'-methylenebis [6-
(2H-1,2,3-benzotriazol-2-yl)
-4- (4-hydroxybutanoyloxyethyl) phenol], 2,2'-methylenebis [6- (2H-1,
2,3-benzotriazol-2-yl) -4- (5-
Hydroxyheptanoyloxyethyl) phenol],
2,2′-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (6-hydroxyhexanoyloxyethyl) phenol], 2,2′-
Methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (16-hydroxy-4,1
1-dioxo-3,10-dioxahexadecyl) phenol], 2,2′-methylenebis [6- (2H-1,
2,3-benzotriazol-2-yl) -4- (23
-Hydroxy-4,11,18-trioxo-3,1
0,17-trioxatricosyl) phenol], 2,
2'-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (30-hydroxy-
4,11,18,25-tetraoxo-3,10,1
7,24-tetraoxahexadecyl) phenol],
2,2′-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (37-hydroxy-4,11,18,25,32-heptaoxo-3,
10,24,31-heptaoxaheptatriacontyl) phenol] and the like. These bisbenzotriazolylphenol compounds (1) can be used alone or in combination of two or more.

In addition to the bisbenzotriazolylphenol compound (1), various known ultraviolet absorbers may be used as long as the preferable properties of the aqueous coating composition of the present invention are not impaired.
A hindered amine light stabilizer and other polymer additives can be used in combination. The amount of the bisbenzotriazolylphenol compound (1) to be used is generally 0.1 to 50 parts by weight, preferably 0.1 to 100 parts by weight, per 100 parts by weight of the monomer.
It is preferably in the range of 5 to 10 parts by weight.

The aqueous coating composition of the present invention is produced by adding a bisbenzotriazolylphenol compound (1) to an emulsifier-containing polymer and mixing them. More specifically, the bisbenzotriazolylphenol compound (1) may be dissolved or dispersed in water or an inert solvent and added to the emulsifier-containing polymer at room temperature according to a usual method.

Examples of the inert solvent include alcohols such as ethanol and butanol, ketones such as acetone and methyl ethyl ketone, and halogenated hydrocarbons such as chloroform and dichloromethane. In the present invention, an emulsifier can be added when the aqueous coating composition of the present invention is manufactured, separately from the emulsifier when the emulsifier-containing polymer is manufactured.

As the emulsifier, the same ones as exemplified above can be used. The addition of the emulsifier is performed in the same manner as the addition of the ultraviolet absorber (bisbenzotriazolylphenol compound (1)). That is, the emulsifier may be dissolved or dispersed in the above-mentioned inert solvent or water and added to the emulsifier-containing polymer.

The order of addition is not particularly limited, but it is preferable to add the emulsifier and the ultraviolet absorber in this order, or to mix and add the emulsifier and the ultraviolet absorber at the same time. The amount of the emulsifier used is the sum of the amount used for producing the emulsifier-containing polymer and the amount of the monomer 1 used.
The amount may be usually adjusted to 0.5 to 30 parts by weight, preferably 1 to 15 parts by weight with respect to 00 parts by weight.

The aqueous coating composition of the present invention may optionally contain a thickener (for example, trade name: Alon 707)
0, manufactured by Toa Gosei Chemical Industry Co., Ltd.), an antifoaming agent (for example, trade name: Nobuco 8034, manufactured by Sanmobuco Co., Ltd.), a dispersant (for example, trade name: Primal 850, manufactured by Rohm and Haas Co., Ltd.) , A film-forming auxiliary (for example, butyl glycol), a freeze stabilizer (for example, methyldiglycol), an antioxidant (for example, phenols), a micropreservative, a preservative,
Organic pigments, inorganic pigments and the like can be blended.

[0045]

The present invention will be specifically described below with reference to examples, reference examples and test examples. Example 1 (a) Emulsifier-containing polymer: acrylic emulsion A1
Preparation of Ion-exchanged water (600 g) was added to a 3-liter four-necked flask equipped with a stirrer, thermometer, cooling tube and dropping funnel, and the temperature was raised to 80 ° C. in a nitrogen stream with stirring.

Next, a polymerizable monomer mixture comprising 480 g of butyl acrylate, 720 g of methyl methacrylate and 24 g of acrylic acid, an anionic emulsifier (trade name: Newcol 707SF, manufactured by Nippon Emulsifier Co., Ltd.) 61.2
g, 402.6 g of ion-exchanged water and 61.2 g of a 10% aqueous solution of ammonium persulfate were mixed to prepare a monomer emulsion.

This emulsion was added dropwise to the flask over 3.5 hours with stirring. At that time, the reaction temperature was set at 8
It was kept at 0 ° C. ± 1 ° C. After the completion of the dropwise addition, 3.0 g of a 10% aqueous ammonium persulfate solution was added, and further 2.5
Stirred for hours. The reaction mixture is then cooled to room temperature,
The pH was adjusted to 8.6 by adding 16 g of 28% aqueous ammonia, and the nonvolatile content was 49.3%, the viscosity was 70 cps, and the pH was 8.
6 and an acrylic emulsion A1 having an average particle size of 0.19 μm were obtained. (B) Preparation of water-based paint 1 Acrylic emulsion A1 10 obtained in (a) above
0 g, while stirring, 2.5 g of a 60% aqueous solution of a nonionic emulsifier (trade name: Newcol 723, manufactured by Nippon Emulsifier Co., Ltd.) and a thickener (trade name: Aron-7070,
0.5 g of Toa Chemical Industry Co., Ltd.)
0.88 g of a 56.7% ethanol solution of 2′-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (3-hydroxypropanoyloxyethyl) phenol] was added. And uniformly mixed to obtain the title water-based paint. Examples 2 to 4 (Preparation of aqueous paints 2 to 4) In Example 1 (b),
Instead of a solution of 2,2′-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- (3-hydroxypropanoyloxyethyl) phenol in ethanol, 2,2′- Methylene bis [6- (2H-
1,2,3-benzotriazol-2-yl) -4-
1.5 g of a 33.3% (4-hydroxybutanoyloxyethyl) phenol] butanol solution (Example 2), 2,2′-methylenebis [6- (2H-1,2,2,2)
1.28 g of a 38.9% ethanol solution of 3-benzotriazol-2-yl) -4- (16-hydroxy-4,11-dioxo-3,10-dioxahexadecyl) phenol] (Example 2), 2,2'-methylenebis [6
-(2H-1,2,3-benzotriazol-2-yl) -4- (30-hydroxy-4,11,18,25
-Tetraoxo-3,10,17,24-tetraoxahexadecyl) phenol] in 1.28 g of a 39.6% ethanol solution (Example 3), to thereby obtain the water-based paints 2 to 4 as indicated. Example 5 (a) Preparation of Acrylic Emulsion A2 Instead of the polymerizable monomer mixture of butyl acrylate, methyl acrylate and acrylic acid of Example 1 (a), 200 g of butyl acrylate and 80 g of methyl methacrylate were used. Example 1 except that a polymerizable monomer mixture consisting of styrene, 120 g and acrylic acid 8 g was used.
As in (a), the nonvolatile content was 49.5%, and the viscosity was 116.
An acrylic emulsion A2 having cps, pH 8.0 and an average particle diameter of 0.1 micron was obtained. (B) Preparation of water-based paint 5 100 g of the acrylic emulsion A2 obtained in the above example (a) was used as an acrylic emulsion, and 2,2'-methylenebis [6- (2H-1,
2,3-benzotriazol-2-yl) -4- (16
-Hydroxy-4,11-dioxo-3,10-dioxahexadecyl) phenol] in an amount of 1.28 g of a 38.9% ethanol solution, and 2.5 g of a 60% aqueous solution of Newcol 780 as a nonionic emulsifier. Was obtained in the same manner as in Example 1 (b). Example 6 (a) Preparation of Acrylic Emulsion A3 Instead of the polymerizable monomer mixture of butyl acrylate, methyl acrylate and acrylic acid in Example 1 (a), 160 g of 2-ethylexyl methacrylate, methacryl 80 g of butyl acrylate, 76 g of 2-hydroxyethyl acrylate, 80 g of styrene and 4 g of methacrylic acid
Example 1 except that a polymerizable monomer mixture consisting of
As in (a), the nonvolatile content is 50.3% and the viscosity is 95c.
An acrylic emulsion A3 having a ps of pH 8.0 and an average particle diameter of 0.1 micron was obtained. (B) Preparation of water-based paint 6 100 g of the above-mentioned acrylic emulsion A3 as an acrylic emulsion and 2,2'-methylenebis [6- (2H-1,2,3-benzotriazol-2-yl) -4- as an ultraviolet absorber. (16-hydroxy-4,11-
Example 1 (b) except that 1.28 g of a 38.9% ethanol solution of dioxo-3,10-dioxahexadecyl) phenol] and 2.1 g of a 70% aqueous solution of Newcol 520 were used as a nonionic emulsifier. ) Was obtained in the same manner as in the above). Comparative Example 1 (Preparation of water-based paint 7) Newcol 723 (nonionic emulsifier, Nippon Emulsifier Co., Ltd.) was added to 100 g of the acrylic emulsion A1 obtained in Example 1 (a) while stirring.
2.5% of a 60% aqueous solution and 0.5 g of Aron 7070 (thickener, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
After mixing uniformly, the water-based paint 7 was obtained. Comparative Example 2 (Preparation of water-based paint 8) Aron 7070 (a thickener, manufactured by Toa Gosei Chemical Industry Co., Ltd.) was added to 100 g of the acrylic emulsion A1 obtained in Example 1 (a) while stirring.
5 g of 2- (2′-hydroxy-5′-methylphenyl) -2H-benzotriazole (trade name: Tinuvin P, manufactured by Ciba Specialty Chemicals)
1.28 g of a 9% ethanol solution was added in this order and mixed, but a large amount of aggregates were formed and an emulsion having a stable emulsified state was not obtained. Comparative Example 3 (Preparation of water-based paint 9) Ion-exchanged water 20 was placed in a 1-L four-necked flask equipped with a stirrer, thermometer, cooling pipe, and dropping funnel.
0 g was added, and the temperature was raised to 80 ° C. in a nitrogen stream with stirring.

Next, 408 g of a mixture of polymerizable monomers consisting of 200 g of butyl acrylate, 80 g of methyl methacrylate, 120 g of styrene and 8 g of acrylic acid, Newcol 707SF (anionic emulsifier, manufactured by Nippon Emulsifier Co., Ltd.) 20 0.3 g, 2- (2'-hydroxy-
3 ', 5'-di-tert-butylphenyl) -2H-
While stirring a monomer emulsion prepared by mixing 4.08 g of benzotriazole (trade name: Tinuvin 320, manufactured by Ciba Specialty Chemicals), 192.9 g of ion-exchanged water, and 2.04 g of a 10% aqueous solution of ammonium persulfate, the mixture was stirred for 80 minutes. At ℃ was dropped into the flask. A large amount of aggregates were formed, and an emulsion having a stable emulsified state could not be obtained.

From these results, it was found that the water-based paints of Examples 1 to 6 containing the bisbenzotriazolylphenol compound (1) as an ultraviolet absorber and the water-based paint of Comparative Example 1 containing no ultraviolet absorber were agglomerated. No product was formed, and the emulsified state was found to be stable. On the other hand, it can be seen that the water-based paints (Comparative Examples 2 to 3) to which the conventional ultraviolet absorber was added generate aggregates and the emulsified state is unstable. Test Example 1 Each of the aqueous paints obtained in Examples 1 to 6 and Comparative Example 1 was placed on a tin plate (300 × 100 × 0.5 mm).
Bar coater (PI-121D, Tester Sangyo Co., Ltd.)
And baked at 110 ° C. for 5 minutes to obtain a baked coated plate having a film thickness of 25 μm.

Next, a test piece obtained by cutting the coated plate into a size of 70 × 150 mm was applied to a Ducycle sunshine weather meter (trade name: WEL-SUN).
-DC, manufactured by Suga Test Machine Co., Ltd., black panel temperature 63
C., rainfall for 18 minutes every 120 minutes), and the surface gloss of the test piece was measured every 300 hours.

The glossiness (initial value) measured at 20 ° for the test piece not subjected to the weather resistance test is as follows:
The time during which 80% was maintained in the weather resistance test was defined as the deterioration time (hour). The measurement results are shown in Table 1 below.

[0052]

[Table 1] As is clear from Table 1, the coating films formed from the water-based coating materials of Examples 1 to 6 are excellent over a long period of time as compared with the coating films formed from the water-based coating materials of Comparative Example 1 (without adding an ultraviolet absorber). It can be seen that the weather resistance was maintained.

[0053]

The bisbenzotriazolylphenol compound (1) used in the present invention has excellent weather resistance, heat resistance and metal ion resistance, is easily soluble in an organic solvent, and has an emulsifier-containing polymer ( (Emulsion polymer). Therefore, in the present invention, a water-based paint having a stable emulsified state that is unlikely to generate a gel or liquid separation can be obtained, and a coating film having excellent weather resistance can be formed over a long period of time.

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁷ Identification symbol FI // C07D 249/20 502 C07D 249/20 502 C09K 3/00 104 C09K 3/00 104C (56) References JP-A-10- 265557 (JP, A) JP-A-9-316060 (JP, A) Patent 2918543 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 5/00-5/02 C09D 5 / 32 C09D 7/12 C09D 133/00-133/26 C09D 157/00-157/12 C09K 3/00 104

Claims (1)

(57) [Claims] (1) (I) ( meth) acrylic acid, (meth)
An emulsifier-containing polymer obtained by polymerizing one or more monomers selected from the group consisting of lylic esters and aromatic vinyls in the presence of an emulsifier; and (II) a general formula (1): Embedded image In the formulas, A represents a main styrene group. R ³ and R ⁴ are the same or different and each represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms,
It represents an aryl group, an alkoxy group having 1 to 4 carbon atoms or a halogen atom. R ¹ and R ² are the same or different,
Group (B): (Wherein, R ⁵ is directly bonded or has 1 to 1 carbon atoms.
2 represents a linear or branched alkylene group. R ⁶ and R ⁷ are the same or different and each represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. m represents an integer of 1 to 20, and n represents an integer of 4 to 8). And a bisbenzotriazolylphenol compound represented by the formula: