JP2000007882A - Emulsion composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an emulsion composition for coating materials affording coating films of high weatherability, chemical resistance and water resistance by incorporating a polymerizable unsaturated monomer with an organoalkoxysilane compound and others. SOLUTION: This emulsion composition is obtained by incorporating (A) 100 pts.wt. of a polymerizable unsaturated monomer with (B) 0.05-100 pts.wt. of an organoalkoxysilane compound having both glycidyl and hydrolyzable alkoxysilane groups in one molecule, (C) 0-50 pts.wt. of an epoxy group-contg. unsaturated monomer (pref. an unsaturated monomer having alicyclic epoxy or methyl glycidyl group), (D) 0-50 pts.wt. of a hydroxyl-contg. polymerizable unsaturated monomer, (E) 0-10 pts.wt. of an aluminum chelate compound, and (F) 0-5 pts.wt. of a hindered amine-based light stabilizer (HALS) with a base constant (pKb) of pref. >=8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to weather resistance, chemical resistance,
It is an object of the present invention to provide an emulsion composition having excellent water resistance and the like and a coating composition using the same.

[0002] The emulsion composition and the coating composition of the present invention are applied to plastic coating, metal coating, building material coating and the like, and applicable substrates are plastics such as ABS, polycarbonate, polyphenylene oxide, polyamide, etc. Metals such as rolled steel sheet, zinc-coated steel sheet, iron sheet coated with cationic electrodeposition, aluminum, aluminum anodized, and the like, and inorganic materials such as glass, asbestos cement pearlite, mortar, and slate board.

[0003]

2. Description of the Related Art In recent years, from the viewpoints of environmental protection, safety and health, and energy saving, conventional organic solvent-based paints have been replaced with water-based emulsion paints such as acrylic resin emulsion paints as safe and environmentally friendly paints. As the switching progresses, its applications are expanding,
Accompanying this, the required performance of emulsion resins is becoming more and more advanced. However, in the case of a water-based emulsion paint such as an acrylic resin emulsion paint, an excellent one in a well-balanced basic performance required for paints such as weather resistance, chemical resistance, and water resistance has not been found.

In order to improve these performances, an acrylic silicone emulsion obtained by converting an acrylic resin emulsion into a silicone has been proposed. However, during storage of the acrylic emulsion, an alkoxysilane moiety is hydrolyzed, and intra-particle crosslinking proceeds. There is a problem that the emulsion thickens and gels.

In order to solve this problem, Japanese Patent Laid-Open Publication No.
27312, JP-A-5-25354, JP-A-7-62036, JP-A-7-133396, JP-A-7-268301, JP-A-8-735
No. 43, Japanese Patent Application Laid-Open No. 9-12906, etc. have been proposed, but the film-forming properties are poor and the storage stability is insufficient. Further, problems such as weather resistance and adhesiveness have not been solved, and a material applicable to various substrates has not been developed.

Further, in order to improve weather resistance, patents using a polymerizable or post-addition type ultraviolet absorber or light stabilizer have been issued. For example, JP-A-3-12897
8, JP-A-7-157625, JP-A-8-157
Although the invention described in 193180 is proposed,
When exposed to wind, rain, or light for a long period of time as a coating, migration to the coating surface and detachment from the coating occur.
Performance could not be maintained for as long as expected. Also, since the coating film is not firmly crosslinked, there is a problem that if the amount used is reduced, the weather resistance has little effect.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art, and provides a highly safe emulsion composition and paint, which have excellent weather resistance, chemical resistance and water resistance. It is intended to provide an emulsion resin for paint having improved coating film performance.

[0008]

In order to solve the above problems, the present invention has the following arrangement. That is, the present invention relates to an organoalkoxysilane compound (B) having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule per 100 parts by weight of the polymerizable unsaturated monomer (A).
An emulsion composition comprising 0.05 to 100 parts by weight.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The polymerizable unsaturated monomer (A) is a component that mainly forms the skeleton of the acrylic resin, and includes, for example, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, and tertiary acrylate. L-butyl, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, tricyclodecyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacryl There are tertiary butyl acid, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, stearyl methacrylate, tricyclodecyl methacrylate, isobornyl methacrylate and the like. These may be used alone or as a mixture of two or more.

As the compound (B), an organoalkoxysilane having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule includes γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ -Glycidoxypropyltriisopropyloxysilane, γ-glycidoxypropylmethyldiethoxysilane and the like, and these compounds may be used alone or as a mixture of two or more. Further, partial condensates of these compounds may be used.

Organoalkoxysilane compound (B)
Is based on 100 parts by weight of the polymerizable unsaturated monomer (A).
0.05 to 100 parts by weight are blended, whereby a paint excellent in various properties such as curability, storage stability and weather resistance can be obtained.

If the amount is less than 0.05 part by weight, the crosslinkability of the coating film becomes low, and there is a concern that the weather resistance over a long period of time is concerned.
Further, satisfactory solvent resistance and stain resistance cannot be obtained. 10
If it is used in excess of 0 parts by weight, coagulation and gelation are likely to occur when preparing the acrylic emulsion, which is not preferable. In addition, the coating film is hard and brittle, and cracks and peeling are likely to occur, which is not preferable.

In the present invention, a hydrolyzable silicone compound other than the organoalkoxysilane compound (B) having a glycidyl group in one molecule can be used in combination.
Hydrolyzable silicone compounds that can be used in combination include γ-
Mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, γ-chloropropyltrimethoxysilane, dimethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane,
Phenyltrimethoxysilane, phenyltriethoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, dimethyldiethoxysilane, and (partial) condensates thereof, and the like.
It does not have radical copolymerizability with the polymerizable unsaturated monomer (A).

In the present invention, although sufficient cross-linking properties are obtained, the epoxy group-containing unsaturated monomer (C) is added to 100 parts by weight of the polymerizable unsaturated monomer (A) in view of coating film performance. From 50
It is preferable to mix it in a weight part or less. When the content is 0.5 to 50 parts by weight, more excellent coating film performance can be obtained, which is more preferable.
On the other hand, if it is used in an amount exceeding 50 parts by weight, the storage stability of the composition deteriorates, and the object of the present invention cannot be achieved.

The epoxy group-containing unsaturated monomer (C) of the present invention includes glycidyl acrylate, glycidyl methacrylate and the like.
It may be a mixture of more than one kind.

The epoxy group-containing unsaturated monomer (C) of the present invention is preferably an unsaturated monomer having an alicyclic epoxy group or an unsaturated monomer having a methylglycidyl group.

Examples of the unsaturated monomer having an alicyclic epoxy group include 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylethyl acrylate, 3,4-epoxycyclohexylpropyl acrylate, and 3,4-epoxycyclohexylpropyl acrylate. There are epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexylethyl methacrylate, 3,4-epoxycyclohexylpropyl methacrylate and the like, and these may be used alone or as a mixture of two or more.

Examples of the unsaturated monomer having a methyl glycidyl group include methyl glycidyl acrylate and methyl glycidyl methacrylate, which may be used alone or as a mixture of two or more.

In the present invention, 50 parts by weight or less of the hydroxyl group-containing polymerizable unsaturated monomer (D) is mixed with 100 parts by weight of the polymerizable unsaturated monomer (A) from the viewpoint of coating film performance. Is preferred. When the content is 0.5 to 50 parts by weight, more excellent coating film performance can be obtained, which is more preferable. On the other hand, if it is used in excess of 50 parts by weight, the storage stability of the composition will deteriorate, and the object of the present invention will not be achieved. The hydroxyl group-containing polymerizable unsaturated monomer (D) enhances the curability and crosslinkability of the coating, and improves the solvent resistance and weather resistance of the coating film.

Examples of the hydroxyl group-containing polymerizable unsaturated monomer (D) include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2-hydroxyethyl acrylate, and 2-hydroxyethyl acrylate. There are hydroxypropyl, 4-hydroxybutyl acrylate and the like, which may be used alone or as a mixture of two or more.

In the present invention, the aluminum chelate compound (E) is preferably blended in an amount of 10 parts by weight or less based on 100 parts by weight of the polymerizable unsaturated monomer (A). 0.01
When it is contained in an amount of from 10 to 10 parts by weight, more excellent coating film performance can be obtained, more preferably 0.05 to 10 parts by weight. From the viewpoint of curability, 0.01 part by weight or more is preferable, and 0.1 part by weight is preferable.
More than 05 parts by weight is more preferable. When used in an amount of more than 10 parts by weight, it cannot be sufficiently dissolved in the acrylic monomer, and bumps are generated on the coating film, the appearance of the coating film deteriorates, and the storage stability of the composition becomes poor. It becomes worse and the object of the present invention cannot be achieved.

Examples of the aluminum chelate compound (E) include aluminum ethyl acetoacetate diisopropylate, aluminum tris (ethyl acetoacetate), aluminum tris (acetyl acetate), and aluminum bisethyl acetoacetate monoacetylacetonate. A single material or a mixture of two or more materials may be used.

The aluminum chelate compound (E) can be added to the emulsion composition, but in the present invention, it is preferably added at the time of emulsion polymerization and polymerized.

In the present invention, from the viewpoint of weather resistance, it is preferable to add a hindered amine light stabilizer (HALS) (F).

Hindered amine light stabilizer (HALS)
(F) includes bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis (1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)
Sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, tetraoxy (2,2,6,6- Tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate and the like, and these may be used alone or as a mixture of two or more.

These hindered amine light stabilizers (H
ALS) (F) is preferably contained in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the polymerizable unsaturated monomer (A).
By adding 0.1 parts by weight or more, sufficient weather resistance is obtained, and even when used in an amount exceeding 5 parts by weight, the expected long-term performance cannot be maintained, and the storage stability of the composition deteriorates. Therefore, the object of the present invention cannot be achieved.

Hindered amine light stabilizer (HALS)
(F) can be added to the emulsion composition, but is preferably added at the time of emulsion polymerization and polymerized in the present invention.

Hindered amine light stabilizer (HALS)
As (F), a hindered amine light stabilizer (HALS) having a PKb (base constant) of 8 or more is preferable. PKb
As a hindered amine light stabilizer (HALS) having a (base constant) of 8 or more, 1- [2- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4 -[3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy]-
2,2,6,6-tetramethylpiperidine, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-
1,3,8-Triazaspiro [4,5] decane-2,4
-Dione and the like, which may be used alone or as a mixture of two or more.

The emulsion composition of the present invention comprises an organoalkoxysilane compound (B) having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule per 100 parts by weight of the polymerizable unsaturated monomer (A). 0.05-100
It is obtained by emulsion polymerization of a mixture consisting of parts by weight.

More specifically, persulfate compounds such as ammonium persulfate and potassium persulfate as polymerization initiators in, for example, a polymerization temperature of 30 to 100 ° C. in ion-exchanged water;
Organic oxides such as tertiary butyl hydroperoxide, organic azo-based polymerization initiators such as α, α'-azobisisobutyronitrile, etc. are used. As surfactants, fatty acid salts and sulfates of higher alcohols Salt, sulfate salt of liquid fatty oil, sulfate of aliphatic amine and aliphatic amide, phosphate of fatty alcohol, sulfonate of dibasic fatty acid ester, sulfonate of aliphatic amide, alkylallyl sulfonic acid Salts, anionic activators such as formalin condensed naphthalene sulfonate, and nonionic activators such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl ester, sorbitan alkyl ester, and polyoxyethylene sorbitan alkyl ester. Use and mentioned earlier Polymerizable unsaturated monomer (A), and is prepared by emulsion polymerization of a mixture of the organoalkoxysilane compound having a glycidyl group in a molecule (B).

The obtained emulsion composition preferably has a weight average molecular weight of 100,000 or more in view of toughness, weather resistance, and chemical resistance of the coating film. This is preferable in terms of paint viscosity, film forming property, uniformity of coating film, and drying property. Also, the ratio of weight average particle diameter / number average particle diameter is 3 or less, more preferably 2
The following are preferable from the viewpoint of preventing aggregation when preparing an acrylic emulsion, uniformity of a coating film, and weather resistance.

[0033]

The present invention will be described in more detail with reference to the following examples.

Each evaluation in the examples is measured and determined by the following method.

Here, the paint to be used for the test was 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (product CS-12 of Chisso Corp.) as a film-forming aid for the emulsion composition. 5 to 10 PHR
The one added was used.

(1) Gel fraction The composition was applied to a polypropylene plate and dried by heating at 80 ° C for 30 minutes. The coating film was peeled off from the polypropylene plate, and the solvent insoluble matter (gel fraction) was measured using a Soxhlet extractor using acetone / methanol (50/50 vol%) as a solvent. The higher the gel fraction (the larger the numerical value), the better the crosslinkability. Pass if 70% or more.

(2) Weather resistance (performed in accordance with JIS K 5400) A paint was applied to a JIS A 5413 asbestos cement pearlite plate so that the coating thickness became about 50 μm.
After drying for 0 minutes, the material was forcibly dried at 80 ° C. for 30 minutes. A coating material was further applied on this coated plate so that the thickness of the coating film became about 50 μm, dried at room temperature for 10 minutes, and then forcibly dried at 80 ° C. for 30 minutes. This was dried at room temperature for 2 weeks. Using a coated plate after drying, use a sunshine weatherometer (SWO)
M) was used to perform an accelerated weathering test for 4000 hours.
Gloss retention (gloss after accelerated weathering test / gloss before test ×
A case where the color difference (ΔE) is 2 or less is 80% or more (represented by 100) and the color difference (ΔE) is 2 or less. Otherwise, it is rejected.

(3) Water-resistant paint is applied to a glass plate with a 10 mil applicator,
After drying at room temperature for 10 minutes, it was forcibly dried at 80 ° C. for 30 minutes. The coated plate is dried at room temperature for 5 days, immersed in warm water at 60 ° C., and subjected to a test for 24 hours. Further, while the coated plate is immersed in the warm water, the container containing the warm water is left to cool naturally, and the test is continued for 24 hours. The state of the coating film after the test is observed and evaluated. ：: There is no change in the state of the coating film, which is the same as before the test. Pass Δ: The coating film is slightly whitened, but returns to its original state after drying. Pass: The coating film is whitened. Does not recover after drying. Failure (4) Storage stability About 80 ml of the acrylic silicone emulsion was placed in a 100 ml glass bottle, sealed, and allowed to stand at 40 ° C. for one month. One month later, the state of the acrylic silicone emulsion was visually determined. ：: Good without aggregation, thickening, precipitation, separation, etc. Pass △: Viscosity, separation, sedimentation, etc. of twice or less as compared to before the test are observed. Pass ×: Viscosity, separation, sedimentation, etc. more than twice as high as before the test are observed. failure.

In the following Examples and Comparative Examples, each raw material in the table is supposed to be carried out at 5 times (g) the indicated weight, and the meanings of the abbreviations in the table are as follows. .

Β-CEA: polymerizable carboxylic acid. A mixture of acrylic acid / acrylate of hydroxypropionic acid / acrylate of di (hydroxypropionate) / acrylate of tri (hydroxypropionate). (Corresponding to Shippomer β-CEA manufactured by Rhone Poulin Co., Ltd.) KBM-403: an organoalkoxysilane compound having at least one glycidyl group in one molecule. γ-glycidoxypropyltrimethoxysilane. (Product of Shin-Etsu Silicone Co., Ltd.) SZ-6030: an organoalkoxysilane compound not having at least one glycidyl group in one molecule. Polymerizable organoalkoxysilane compounds. γ-methacryloyloxypropyltrimethoxysilane. (Product of Dow Corning Toray Silicone Co., Ltd.) GMA: Epoxy group-containing unsaturated monomer. Glycidyl methacrylate M-100: an unsaturated monomer having an alicyclic epoxy group. 3,4-epoxycyclohexylmethyl methacrylate. (Product of Daicel Chemical Industries, Ltd.) HEMA: hydroxyl-containing polymerizable unsaturated monomer. 2-hydroxyethyl methacrylate HEA: a hydroxyl group-containing polymerizable unsaturated monomer. Acrylic acid 2
-Hydroxyethyl aluminum chelate AW: aluminum chelate compound. Aluminum tris (acetyl acetate). (Product of Kawaken Fine Chemical Co., Ltd.) Aluminum chelate D: Aluminum chelate compound. Aluminum monoacetylacetonate bis (ethylacetoacetate). (Product of Kawaken Fine Chemical Co., Ltd.) SANOL LS-2626: a hindered amine light stabilizer. 1- [2- [3- (3,5-di-t-butyl-4-
[Hydroxyphenyl) propionyloxy] ethyl]-
4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine. (Product of Sankyo Co., Ltd.) SANOL LS-440: Hindered amine light stabilizer.
8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4.5] decane-2,4-dione. (Products of Sankyo)

Example 1 500 Ion-exchanged water was placed in a 2 L four-necked flask equipped with a stirrer, thermometer, condenser and monomer supply pump.
g, 20 g of an anionic surfactant (polyoxyethylene lauryl sulfate). 80 ° C with stirring
Temperature to ammonium persulfate (persulfate compound)
After adding 2.5 g, the raw material mixture shown in Example 1 of Table 1 and 5 g of a nonionic surfactant (polyoxyethylene alkylphenyl ether) are supplied into the flask by a monomer supply pump in 3 hours. After the completion of the supply, the polymerization is further continued for 1.5 hours, and then cooled to 30 ° C.

While stirring the emulsion, the pH (25
(° C.) is 7.0 to 9.0 (the amount at which the degree of neutralization of the copolymerized carboxylic acid becomes about 60% to 80%) 2
Slowly add 5% aqueous ammonia. Thus, an emulsion composition of Example 1 was obtained.

Table 4 shows the test results of the obtained emulsion composition.

Examples 2 to 32 and Comparative Examples 1 to 18 were prepared in the same manner as in Example 1 except that the raw material compositions were changed as shown in Tables 1 to 3. (Comparative Examples 2 to 10
Gelled during emulsion polymerization, and no emulsion could be prepared. Tables 4 to 6 show the test results of the obtained emulsion compositions.

[0045]

[Table 1]

[0046]

[Table 2]

[0047]

[Table 3]

[0048]

[Table 4]

[0049]

[Table 5]

[0050]

[Table 6]

[0051]

The emulsion composition of the present invention can provide a coating film having excellent weather resistance and water resistance.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 CP051 EH058 EH076 EL037 EU079 EU089 EU109 EZ009 FD049 GH01 HA07 4J038 CG141 CH031 CH041 CH071 CJ131 DB221 FA121 FA131 FA152 FA172 GA03 GA07 GA15 JB30 JB33 MA03 NA03 MA03

Claims (7)

[Claims] An organoalkoxysilane compound (B) having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule per 100 parts by weight of the polymerizable unsaturated monomer (A) is 0.05 to 100 parts by weight. Parts, 0 to 50 parts by weight of an epoxy group-containing unsaturated monomer (C), 0 to 50 parts by weight of a hydroxyl group-containing polymerizable unsaturated monomer (D), 0 to 10 parts by weight of an aluminum chelate compound (E), and An emulsion composition comprising 0 to 5 parts by weight of a hindered amine light stabilizer (HALS) (F). 2. An epoxy group-containing unsaturated monomer (C) in an amount of 0.5 to 5 parts by weight per 100 parts by weight of the polymerizable unsaturated monomer (A).
2. The emulsion composition according to claim 1, comprising 0 parts by weight. 3. The emulsion composition according to claim 2, wherein the unsaturated monomer having an epoxy group (C) is an unsaturated monomer having an alicyclic epoxy group or an unsaturated monomer having a methylglycidyl group. object. 4. A polymerizable unsaturated monomer having a hydroxyl group (D) of 0.5 to 100 parts by weight based on 100 parts by weight of the polymerizable unsaturated monomer (A).
The emulsion composition according to any one of claims 1 to 3, comprising 50 parts by weight. 5. An aluminum chelate compound (E) in an amount of 0.01 to 100 parts by weight of the polymerizable unsaturated monomer (A).
The emulsion composition according to any one of claims 1 to 4, comprising 10 parts by weight. 6. A hindered amine light stabilizer (HALS) based on 100 parts by weight of the polymerizable unsaturated monomer (A).
The emulsion composition according to any one of claims 1 to 5, comprising (F) 0.1 to 5 parts by weight. 7. A hindered amine light stabilizer (HALS)
The emulsion composition according to claim 6, wherein the PKb (base constant) of (F) is 8 or more.