JP2000109747A - Production of silicon-including aqueous coating agent composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition excellent in polymerization stability, leaving stability, weather resistance, water resistance and the like by emulsion polymerization of an unsaturated monomer including a hydrolyzable silyl group and other unsaturated monomers in the presence of an emulsifier or the like. SOLUTION: This composition is obtained by emulsion polymerization of (A) an unsaturated monomer including a hydrolyzable silyl group [preferably γ-(meth)acryloxyethyltrimethoxysilane or the like] and (B) other unsaturated monomers (preferably styrene or the like) in the presence of (C) an emulsifier, (D) a polymerization initiator and (E) along-chain unsaturated fatty acid copolymer-based polymer dispersant (preferably a ricinoleic acid copolymer-based polymer dispersant) in an aqueous medium. The copolymerization ratio of A and B is preferably (A/B) (weight ratio) of (1:99) to (70:30). It is preferable to compound 0.1-10 pts.wt. component C, 0.03-40 pts.wt. component D and 0.03-40 pts.wt. component E based on the total of 100 pts.wt. components A and B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a silicon-containing aqueous coating composition (hereinafter referred to as a coating composition) having excellent polymerization stability, shelf stability, freeze-thaw stability, weather resistance, water resistance and solvent resistance of an emulsion. The present invention relates to a method for producing a coating composition useful as a coating material for building materials, adhesives, and paper.

[0002]

2. Description of the Related Art A resin containing a monomer containing an alkoxysilyl group (hydrolyzable silyl group), particularly an acryl-silicone resin, has room-temperature curability, forms a high-hardness coating film, and has weather resistance. It has been used as an adhesive, a binder for paint, and a paper coating agent because of its excellent performance such as stain resistance. Furthermore, in recent years, in the field of paints and adhesives, attempts have been made to switch from using organic solvents to emulsions from the viewpoint of pollution control and resource saving. Various attempts have been made for the polymerization of such emulsions. For example, as an example of emulsion polymerization using an alkoxysilyl group-containing monomer, JP-B-7-26035
JP-A-5-33 discloses a reactive resin emulsion containing a resin having at least one hydrolyzable silyl group and one amine imide group in each molecule.
No. 1408 discloses a vinyl copolymer in which a hydrolyzable silyl group and a carboxyl group are used in one molecule, and a water-soluble resin obtained by neutralization with ammonia or an organic amine compound is used as a dispersion stabilizer. Also disclosed is a curable composition for aqueous dispersion-type paint containing a hydrolyzed silyl group-containing vinyl polymer dispersed and polymerized in an aqueous medium in the presence of the resin.

[0003]

However, in the above-mentioned disclosed technology, although the weather resistance and the solvent resistance are improved to some extent, the emulsion polymerization stability, standing stability and freeze-thaw stability are still satisfactory. Has not been obtained. Therefore, it is clear that further research is required for the development of a method for producing an emulsion having good polymerization stability, storage stability, freeze-thaw stability, and excellent weather resistance, water resistance, and solvent resistance. became.

[0004]

The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, have found that the unsaturated monomer (A) containing a hydrolyzable silyl group and other unsaturated monomers. When the saturated monomer (B) is emulsion-polymerized in an aqueous medium in the presence of an emulsifier (C), a polymerization initiator (D), and a long-chain unsaturated fatty acid copolymer-based polymer dispersant (E),
The present inventors have found that a coating composition (emulsion) having good polymerization stability, standing stability, freeze-thaw stability, and excellent weatherability, water resistance and solvent resistance can be obtained, and completed the present invention.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. First, the raw materials used in the present invention will be described.

In the present invention, an unsaturated monomer (A) containing a hydrolyzable silyl group and another unsaturated monomer (B) are emulsion-polymerized in an aqueous medium. As the unsaturated monomer (A) containing a hydrolyzable silyl group, γ- (meth) acryloxyethyltrimethoxysilane, γ- (meth) acryloxyethyltriethoxysilane, γ- (meth) acryl Roxypropyltrimethoxysilane, γ- (meth)
Acryloxypropyltriethoxysilane, γ- (meth) acryloxypropylmethyldimethoxysilane, γ
-(Meth) acryloxypropyldimethylmethoxysilane, γ- (meth) acryloxypropylmethyldiethoxysilane, γ- (meth) acryloxypropyldimethylethoxysilane, γ- (meth) acryloxypropyltrichlorosilane, γ- ( (Meth) acryloxypropylmethyldichlorosilane, γ- (meth) acryloxypropyldimethylchlorosilane, γ- (meth) acryloxypropyltripropoxyoxysilane, γ- (meth) acryloxypropylmethyldipropoxyoxysilane, γ- ( (Meth) acryloxypropyltributoxysilane, γ-
(Meth) acryloxybutyltrimethoxysilane, γ-
(Meth) acryloxypentyltrimethoxysilane, γ
-(Meth) acryloxyhexyltrimethoxysilane,
γ- (meth) acryloxyhexyltriethoxysilane, γ- (meth) acryloxyoctyltrimethoxysilane, γ- (meth) acryloxydecyltrimethoxysilane, γ- (meth) acryloxydodecyltrimethoxysilane, γ- (Meth) acryloxyoctadecyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldipropoxysilane, and the like.

Preferably, γ- (meth) acryloxyethyltrimethoxysilane, γ- (meth) acryloxyethyltriethoxysilane, γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryloxypropyl Triethoxysilane, γ- (meth) acryloxypropylmethyldimethoxysilane, γ- (meth) acryloxypropyldimethylmethoxysilane, γ- (meth) acryloxypropylmethyldiethoxysilane, γ
-(Meth) acryloxypropyldimethylethoxysilane, γ- (meth) acryloxybutyltrimethoxysilane, γ- (meth) acryloxypentyltrimethoxysilane, γ- (meth) acryloxyhexyltrimethoxysilane, γ- ( (Meth) acryloxyhexyltriethoxysilane, γ- (meth) acryloxyoctyltrimethoxysilane, γ- (meth) acryloxydecyltrimethoxysilane, γ- (meth) acryloxydodecyltrimethoxysilane, γ- (meth) Acryloxyoctadecyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, and vinylmethyldiethoxysilane.

The other unsaturated monomer (B) used in the present invention is not particularly limited as long as it has a radical polymerizability other than (A). Specifically, styrene, methyl ( (Meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-
Butyl (meth) acrylate, isoptyl (meth) acrylate, 2-ethylhexyl acrylate, n-hexyl methacrylate, lauryl methacrylate, vinyl acetate, vinyl t-decanoate, tridecyl (meth) acrylate, stearyl (meth) acrylate, hexyl (meth) Acrylate, cyclohexyl (meth) acrylate, octyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, vinyltoluene, (meth) acrylonitrile, dialkyl itaconate, dialkyl fumarate, dialkyl maleate Esters, acrylic chloride, acetoacetylated (meth) acrylate,
(Meth) acrylamide, (meth) acrylic acid, crotonic acid, fumaric acid, (anhydride) maleic acid, itaconic acid,
Carboxyl group-containing monomers such as citraconic acid and ricinoleic acid and salts thereof (ammonium salts, amine salts, sodium salts, potassium salts) are used, and these are used alone or in a mixture of two or more kinds. , Styrene, methyl (meth) acrylate, ethyl acrylate, n-butyl (meth) acrylate, 2-ethylhexyl acrylate, vinyl acetate, (meth) acrylic acid (ammonium salt, diethylamine salt), crotonic acid (ammonium salt, diethylamine salt) And itaconic acid (ammonium salt, diethylamine salt) are preferred.

The emulsifier (C) used in the present invention refers to each component of the unsaturated monomer (A) containing a hydrolyzable silyl group and the other unsaturated monomer (B) during the production of the present invention. It is not particularly limited as long as it has a function of emulsifying the compound in an aqueous medium, and may be any of anionic, nonionic, and cationic, and may have surface activity and reactivity. Specifically, anionic emulsifiers such as sodium dodecylbenzenesulfonate, sodium laurate, sodium alkyldiphenylsulfonate, sodium polyoxyethylene alkyl ether sulfate, polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ether, and polypropylene glycol Nonionic emulsifiers such as ethylene oxide adducts; cationic emulsifiers such as stearylbenzyldimethylammonium chloride and distearylbenzyldimethylammonium chloride; and sulfosuccinates (such as sodium alkylarylsulfosuccinate);
Examples thereof include reactive emulsifiers such as alkylphenol ether-based and sodium (meth) acryloylpolyoxyalkylene sulfate, and the use of a reactive emulsifier is preferred. These may be used alone or in combination of two or more.

The polymerization initiator (D) used in the present invention
Is not particularly limited, and any of water-soluble and oil-soluble can be used. Specifically, alkyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, p-methane hydroperoxide , Isobutyl peroxide, lauryl peroxide,
3,5,5-trimethylhexanoyl peroxide,
Octanoyl peroxide, t-butylcumyl peroxide, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-t
-Butyl peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane,
Organic peroxides such as 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, di-isobutylperoxydicarbonate, di-2-ethylhexylperoxydicarbonate, t-butylperoxyisobutyrate, and azo Bisisobutyronitrile, dimethylazodiisobutyrate, 2,2-azobis (2,4-dimethylvaleronitrile), 2,2-
Azobis (2-methylbutyronitrile), potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, ammonium (amine) salt of 4,4'-azobis-4-cyanovaleric acid, 2,2'- Azobis (2-methylamidoxime) dihydrochloride,
2,2′-azobis (2-methylbutanamide oxime) dihydrochloride tetrahydrate, 2,2′-
Azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] -propionamide}, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propion Amides), various redox catalysts (in this case, oxidizing agents include ammonium persulfate, potassium persulfate, hydrogen peroxide, t-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, p-menthane hydroperoxide, etc. , Sodium sulphite, sodium acid sulphite, Rongalit, ascorbic acid, etc. are used as the reducing agent.) Among them, azobisisobutyronitrile, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide], potassium persulfate, Sodium sulfate, ammonium persulfate, 4,4'-azobis-4-cyanovaleric acid ammonium (amine) salts are preferred.

The most important feature of the present invention is to use a long-chain unsaturated fatty acid copolymer-based polymer dispersant (E) during polymerization in order to further stabilize the polymerization. Oleic acid, elaidic acid, erucic acid,
Linoleic acid, ricinoleic acid, docosahexaenoic acid, linolenic acid, arachidonic acid and the like, preferably,
Ricinoleic acid is used.

[0012] Long chain unsaturated fatty acid copolymer polymer dispersant
In order to obtain (E), (a) the polymerization
Initiator, long chain unsaturated fatty acid and unsaturated monomer
After dividing and charging, the solvent is reduced to normal pressure or reduced pressure.
Removed below, if necessary, basic such as aqueous ammonia
A method of neutralizing with a compound to obtain an aqueous solution of any concentration,
(B) In the presence of water, a polymerization initiator and an emulsifier,
The chain unsaturated fatty acid and the unsaturated monomer are pre-emulsified,
The emulsion is dropped into an aqueous medium, and emulsion polymerization is performed at 40 to 100 ° C.
If necessary, an alkaline aqueous solution such as aqueous ammonia
Neutralization with an aqueous solution of any concentration, etc.
You. Polymer dispersion without using any solvent in method (b)
However, the use of the dispersant slightly increases the polymerization stability.
Therefore, the method (a) is practical and preferable.
The method (a) will be described.

Examples of the water-soluble solvent used above include alcohols such as methanol, ethanol and isopropanol, and ketones such as acetone. The unsaturated monomer used above is not particularly limited, but specifically, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate,
Ethylhexyl acrylate, methyl methacrylate,
Ethyl methacrylate, isopropyl methacrylate,
(Meth) acrylic acid esters such as n-butyl methacrylate, n-hexyl methacrylate and lauryl methacrylate; fatty acid esters such as vinyl acetate, styrene and vinyl versatate; acrylic acid, methacrylic acid, crotonic acid, maleic acid, and maleic anhydride , Fumaric acid, itaconic acid, citraconic acid and other carboxyl group-containing monomers, 1,1,1-trimethylamine methacrylimide, 1,1-dimethyl-1-ethylamine methacrylimide, 1,1-dimethyl-1- (2-hydroxy Propyl) amine methacrylimide, 1,1-dimethyl-1
-(2'-phenyl-2'-hydroxyethyl) amine methacrylimide, 1,1-dimethyl-1- (2'-hydroxy-3'-phenoxypropyl) amine methacrylimide, 1,1,1-trimethylamine acrylimide Or a monomer represented by the following formula (1) or (2), or an unsaturated monomer containing a hydrolyzable silyl group described above.

[0014]

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[0015]

Embedded image

In the above copolymerization, azobisisobutyronitrile, alkyl peroxide, cumene hydroperoxide, p-methane hydroperoxide, isobutyl peroxide, lauryl peroxide, 3,3
5,5-trimethylhexanoyl peroxide, octanoyl peroxide, t-butylcumyl peroxide, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, 1,1-bis (T-butylperoxy) -3,3,5-trimethylcyclohexane, 3,
3,5-trimethylcyclohexanone peroxide,
A catalyst such as an organic peroxide such as methylcyclohexanone peroxide, di-isobutylperoxacidic carbonate, di-2-ethylhexylperoxacidic carbonate is used, and the reaction is carried out in the presence of a chain transfer agent, if necessary. Will be

Although the copolymerization ratio of the two is not particularly limited, the mixing ratio of the long-chain unsaturated fatty acid and the unsaturated monomer at the time of charging is as follows:
Long-chain unsaturated fatty acid / unsaturated monomer (weight ratio) = 1-10
/ 90 to 99 are preferred. When the long-chain unsaturated fatty acid copolymer-based polymer dispersant (E) is out of the above range, the storage stability of the coating composition may be reduced, or sufficient weather resistance and solvent resistance may be lacked when coated. is there.

The water-soluble solvent is used in an amount of 150 to 5 parts by weight based on 100 parts by weight of the total amount of the long-chain unsaturated fatty acid and the unsaturated monomer.
Preferably it is 00 parts by weight.

The polymerization initiator is preferably used in an amount of 0.03 to 5 parts by weight, more preferably 0.05 to 1 part by weight, based on 100 parts by weight of the total amount of the long-chain unsaturated fatty acid and the unsaturated monomer.

The acid value of the copolymer is 50 to 500 mg.
KOH / g is preferred, and 70-300 mg KOH
/ G. When the acid value is less than 50 mgKOH / g, it does not show water solubility even when neutralized with an aqueous alkali solution.
It is difficult to obtain a stable coating agent composition because the emulsifying action is reduced, and if it exceeds 500 mgKOH / g, water resistance is lowered when coated, which is not preferable.

The molecular weight of the above copolymer is not particularly limited, but the number average molecular weight is 500 to 500.
500,000 is preferable, and 700-30 is more preferable.
When the molecular weight is less than 500, the stability of the obtained coating agent composition during polymerization decreases, and
If it exceeds 0, the viscosity increases and the amount of diluent during polymerization increases, which is uneconomical and is not preferred.

Next, the water-soluble solvent is removed from the solution of the copolymer in a water-soluble solvent.
Alternatively, it is removed under reduced pressure, and usually the remaining amount is 1.0% of the entire system.
% By weight, preferably 0.1% by weight or less, to obtain a copolymer. Further, the copolymer is preferably neutralized with a basic compound. Examples of the basic compound include ammonia, N, N-dimethylethanolamine, diethylamine, triethylamine, morpholine, and 2-dimethylamino-2-methyl. -1-propanol, monoisopropanolamine, monoethanolamine, N, N-
Diethylethanolamine, 2-amino-2-methyl-
1-propanol, N-methyldiethanol, diisopropanolamine, N-ethyl-diethanolamine,
Triisopropanolamine, triethanolamine and the like, preferably ammonia, diethylamine,
Triethylamine is used.

The basic compound is preferably used as an aqueous solution (or alcohol solution) of 1 to 50% by weight, and the amount of the basic compound added is 50 equivalents per carboxyl group (of a long-chain unsaturated fatty acid). Add ~ 110% and neutralize with stirring. The neutralization has a pH of 4-1.
0, more preferably from 5 to 9, p
If H is less than 4 or more than 10, the solution viscosity increases, and the stability during polymerization of the coating agent composition described later decreases, which is not preferable.

Next, an emulsion polymerization method for obtaining the composition of the present invention will be described. The copolymerization ratio of (A) and (B) is not particularly limited, but (A) / (B) (weight ratio) = 1 to 7
0/99 to 30 is preferable, and 3 to 50/97 to 5 is more preferable.
0. Outside the above range, the storage stability of the coating agent composition is lowered, and when coated, sufficient weather resistance and solvent resistance cannot be obtained.

The amount of the emulsifier (C) is (A)
It is preferably 0.1 to 10 parts by weight, more preferably 0.3 to 5 parts by weight, based on 100 parts by weight of the total amount of (B). If the amount is less than 0.1 part by weight, stable polymerization cannot be performed, and
Exceeding the weight part is undesirable because the water resistance is poor when coated.

The polymerization initiator (D) is preferably used in an amount of 0.03 to 5 parts by weight, more preferably 0.05 to 1 part by weight, based on 100 parts by weight of the total of (A) and (B).
Parts by weight. If (D) is less than the above range, the polymerization rate will be slow, and if it exceeds the above range, solvent resistance and weather resistance may decrease when coated, which is not preferred.

The long-chain unsaturated fatty acid copolymer-based polymer dispersant (E) is preferably 0.03 to 40 parts by weight, more preferably 0.05 to 40 parts by weight, based on 100 parts by weight of the total of (A) and (B). ~ 2
0 parts by weight. If (E) is less than the above range, stable polymerization cannot be performed, and the resulting coating composition will have reduced storage stability and freeze-thaw stability. Water resistance and weather resistance may decrease, which is not preferable.

As the polymerization method, the above (A) to
(E) is mixed with water to form an emulsified state by mixing and stirring, and then heated to polymerize. The above (A) to (E) is mixed and stirred with water to form an emulsified state, and a part of the mixture is heated to form an emulsified state. A method in which the polymerization is started, the remainder is added dropwise, and the polymerization is continued. After water and an emulsifier (C) and a polymerization initiator (D) are charged into a reaction vessel and the temperature is raised, (A) and (B) , (E), and the like, and a method in which the whole amount of the emulsified mixed solution is dropped at once, divided, or continuously dropped to carry out polymerization. However, it is preferable because the polymerization temperature is easily controlled and the polymerization stability is good.

The polymerization conditions are usually 40 to 90 ° C.
The polymerization is completed within about 1 to 8 hours after the start of the temperature rise. The polymerization conditions for (A)
After polymerizing 5 to 50% by weight of the emulsified mixture of (E) at 40 to 90 ° C. for 0.1 to 4 hours, the remaining emulsified mixture is mixed with 1 to 5%.
The solution is added dropwise over about an hour, and then aged at the same temperature for about 1 to 3 hours. The polymerization conditions are as follows: water is charged to a reaction vessel in an amount of about 50 to 80% by weight of the total amount, an emulsifier (C) and a polymerization initiator (D) are charged, and the temperature is raised to 40 to 90 ° C. The emulsified mixed solution containing the remaining water of A), (B) and (E) is polymerized while being dripped over about 1 to 5 hours, and then aged at the same temperature for about 1 to 3 hours.

The particle size of the obtained emulsion is 50-1.
Approximately 000 nm, dispersed in an aqueous medium, the resulting emulsion is excellent in storage stability, freeze-thaw stability, various performances, for example, weather resistance, water resistance, excellent solvent resistance, building material coatings, adhesives, Useful for paper coating agents and the like.

In addition to the components (A) to (E), known chain transfer agents, defoamers, preservatives, and the like, as long as the effects of the present invention are not impaired.
Rust inhibitors, ultraviolet absorbers, antioxidants and the like may be added. In addition, to promote the curing of the coating film, an organic tin compound,
A curing agent such as an organometallic compound such as an organoaluminum compound may be added, and the curing agent may be added in the form of an emulsion.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below.
In the following description, “%” and “part” are “weight%”,
"Parts by weight". Example 1 (Production of long-chain unsaturated fatty acid copolymer polymer dispersant (E)) In a flask equipped with a condenser, a thermometer, and a stirring blade, 43 parts of methyl methacrylate, 38 parts of 2-ethylhexyl acrylate, and 14 parts of acrylic acid , Ricinoleic acid 5
Part, 2,2'-azobisisobutyronitrile 0.64 part was mixed with iso-propanol 240 part,
Allowed to react for hours. Next, 43 parts of methyl methacrylate,
38 parts of 2-ethylhexyl acrylate, acrylic acid 1
4 parts, ricinoleic acid 5 parts, 2,2'-azobisisobutyronitrile 0.64 parts, iso-propanol 40 parts mixture was charged 3 times every 2 hours, and further iso-propanol 40 parts, 2, A mixture of 1.28 parts of 2′-azobisisobutyronitrile was added and stirred at 80 ° C. for 2 hours to obtain a resin solution having a resin content of 50%. The molecular weight of the resin is 300
00, the acid value was 110 mgKOH / g. After iso-propanol is distilled from the resin solution until the content in the system becomes 0.05% by weight, it is neutralized with aqueous ammonia to disperse a long-chain unsaturated fatty acid copolymer polymer dispersant (E). An aqueous solution was obtained. The composition of the polymer dispersant is methyl methacrylate / 2-ethylhexyl acrylate / acrylic acid / ricinoleic acid = 172/152/56/20 (weight ratio).
[The molar ratio was 25/12/11/1].

(Preparation of Silicon-Containing Aqueous Coating Composition) 10 parts of γ-methacryloxypropyltrimethoxysilane (A) and 90 parts of another unsaturated monomer (B) [45 parts of methyl methacrylate, 2-ethylhexyl acrylate] 45 parts], and 40 parts (solid content: 25%) of the aqueous solution of the polymer dispersant (E) obtained above was added to ion-exchanged water 3
The mixture was mixed with 6 parts and stirred to obtain an emulsified mixture. Place ion-exchanged water 7 in a flask equipped with a condenser, thermometer, and stirring blade.
1 part, 3 parts of emulsifier (C) [made by Asahi Denka, alkylphenol ether-based reactive emulsifier SE-10N], and 0.9 part of potassium persulfate (D) were charged.
The emulsified mixture was added dropwise over time. After dropping, 75 ° C
The reaction was carried out for 2 hours, and polymerization was carried out.
A coating composition comprising an emulsion having 5%, a viscosity of 8 mPa · s (25 ° C.) and a particle diameter of 80 nm was obtained. The polymerization stability during the polymerization and the physical properties of the emulsion were evaluated according to the following criteria. The results are shown in Tables 1 and 2.

(Polymerization Stability) During polymerization, the formation of insoluble deposits and coarse particles on the flask, thermometer, and stirring blade was visually observed as follows. ○ ・ ・ ・ No deposits or coarse particles are observed △ ・ ・ ・ Small amount of deposits or coarse particles are generated × ・ ・ ・ A large amount of deposits or coarse particles are generated

(Stability during Storage) The obtained emulsion was left at room temperature for 3 months, and the state was visually observed.・ ・ ・: No change Δ: The viscosity increased slightly or a small amount of sediment was generated. X: The viscosity increased or a large amount of sediment was generated. Or it gelled. (Freeze-thaw stability) The obtained emulsion was frozen at -10 ° C for 18 hours and then left at room temperature for 6 hours to be thawed. After performing this step for 5 cycles, the state of the emulsion was visually observed and evaluated as follows.・ ・ ・: No change Δ: The viscosity increased slightly or a small amount of sediment was generated. X: The viscosity increased or a large amount of sediment was generated. Or it gelled.

(Water resistance) The obtained emulsion was cast on a glass plate and dried at 25 ° C. for 2 hours. A coating film (thickness: 100 μm) was subjected to a rubbing test (ion-exchanged water 1).
ml was dropped and rubbed five times with a finger), and the state was visually observed. A: No whitening or swelling was observed.・ ・ ・: Slight whitening was observed, but no swelling was observed. Δ: Whitening and blistering were observed. X: Whitening and swelling progressed and eluted in some places. (Solvent resistance) The resulting emulsion was cast on a glass plate and dried at 25 ° C. for 7 days.
0 μm) was immersed in ethyl acetate for 24 hours, and the surface condition was visually observed. A: No change B: Slight swelling and whitening were observed on the surface. Δ: Swelling and whitening spread over the entire surface. ×: The whole was swollen, whitening progressed, and the coating film dropped off from the glass plate.

(Weather resistance) The obtained emulsion was cast on a glass plate and dried at 25 ° C. for 7 days. The coating film (thickness: 100 μm) was exposed outdoors for 6 months, and the state of the coating film was visually observed. A: It was a glossy transparent film.・ ・ ・: The gloss was slightly reduced, and the film state was good. Δ: A decrease in gloss and destruction of the film (whitening, cracks) were observed. X: Significant decrease in gloss and significant film destruction (whitening,
Crack) was observed.

Example 2 The procedure of Example 1 was repeated, except that 10 parts of vinyltriethoxysilane was used instead of 10 parts of γ-methacryloxypropyltrimethoxysilane (A). 8 mPa · s (25 ° C.), particle size 90 nm
Was obtained and evaluated in the same manner as in Example 1. The results are shown in Tables 1 and 2.

Example 3 The procedure of Example 1 was repeated except that the production of the long-chain unsaturated fatty acid copolymer-based polymer dispersant (E) was changed as follows to obtain a solid content of 46%.
%, A coating composition comprising an emulsion having a viscosity of 15 mPa · s (25 ° C.) and a particle diameter of 75 nm was obtained, and evaluated in the same manner as in Example 1. The results are shown in Tables 1 and 2. (Production of long-chain unsaturated fatty acid copolymer polymer dispersant (E)) In a flask equipped with a condenser, a thermometer and a stirring blade, 41 parts of methyl methacrylate, 36 parts of 2-ethylhexyl acrylate, 13 parts of acrylic acid, ricinoleic acid 10
Part, 2,2'-azobisisobutyronitrile 0.64 part was mixed with iso-propanol 240 part,
Allowed to react for hours. Next, 41 parts of methyl methacrylate,
36 parts of 2-ethylhexyl acrylate, acrylic acid 1
A mixture of 3 parts, 10 parts of ricinoleic acid, 0.64 part of 2,2′-azobisisobutyronitrile, and 40 parts of iso-propanol was charged three times every 2 hours. Further, 40 parts of iso-propanol, 2, A mixture of 1.28 parts of 2′-azobisisobutyronitrile was added and stirred at 80 ° C. for 2 hours to obtain a resin solution having a resin content of 50%. The molecular weight of the resin is 30
000, and the acid value was 110 mgKOH / g. From the resin solution, iso-propanol was added at a system content of 0.05%.
After distilling out to a weight percent, the mixture was neutralized with aqueous ammonia to obtain an aqueous solution of a long-chain unsaturated fatty acid copolymer-based polymer dispersant (E). The composition of the polymer dispersant is methyl methacrylate / 2-ethylhexyl acrylate / acrylic acid /
Ricinoleic acid = 164/144/52/40 (weight ratio)
[The molar ratio was 25/12/11/2].

Comparative Example 1 The procedure of Example 1 was repeated except that γ-methacryloxypropyltrimethoxysilane (A) was not used. The solid content was 42%, the viscosity was 8 mPa · s (25 ° C.), and the particle size was 75n
m, a coating composition comprising an emulsion of
Evaluation was performed in the same manner as in Example 1.

Comparative Example 2 Example 1 was repeated except that the long-chain unsaturated fatty acid copolymer-based polymer dispersant (E) was not used, and the same treatment was carried out as follows. The solid content was 45% and the viscosity was 15 mPa · s. s (25 ° C),
A coating composition comprising an emulsion having a particle diameter of 95 nm was obtained and evaluated in the same manner as in Example 1.

Comparative Example 3 In Example 1, SN Dispersant 5020 (a polycarboxylic acid type polymer dispersant, manufactured by San Apro Co.) was used in place of the long-chain unsaturated fatty acid copolymer polymer dispersant (E). A solid content of 44% was carried out in the same manner as in Example 1 except that
%, A coating composition comprising an emulsion having a viscosity of 20 mPa · s (25 ° C.) and a particle diameter of 60 nm was obtained, and evaluated in the same manner as in Example 1. Tables 1 and 2 also show the evaluation results of each comparative example.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

According to the present invention, an unsaturated monomer (A) containing a hydrolyzable silyl group and another unsaturated monomer (B) are used.
Are emulsion-polymerized in an aqueous medium in the presence of an emulsifier (C), a polymerization initiator (D), and a long-chain unsaturated fatty acid copolymer-based polymer dispersant (E). Excellent stability, storage stability, freeze-thaw stability, weather resistance, water resistance, and solvent resistance.

Continuation of the front page (72) Inventor Kimiyuki Kyogoku 2-13-1, Muroyama, Ibaraki-shi, Osaka F-term in the Central Research Laboratory of Nippon Gosei Chemical Industry Co., Ltd. 4J011 KA02 KA04 KA08 KA12 KA15 KA19 KA20 KB14 KB28 PA28 PA56 PC06 4J038 CG141 CG142 CJ132 CJ181 CL001 CL002 GA06 KA09 MA10 NA03 NA04 NA26

Claims (2)

[Claims] 1. An unsaturated monomer (A) containing a hydrolyzable silyl group and another unsaturated monomer (B) are mixed with an emulsifier (C), a polymerization initiator (D), and a long-chain unsaturated monomer. A method for producing a silicon-containing aqueous coating composition, which is emulsion-polymerized in an aqueous medium in the presence of a fatty acid copolymer-based polymer dispersant (E). 2. The silicone-containing aqueous coating composition according to claim 1, wherein the long-chain unsaturated fatty acid copolymer-based polymer dispersant (E) is a ricinoleic acid copolymer-based polymer dispersant. Manufacturing method.