JP2000119560A - Production of silicon-containing aqueous coating agent composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method for a silicon-containing aqueous coating agent composition excellent in leaving stability, coating film transparency, weatherability stain resistance, water resistance and solvent resistance. SOLUTION: This composition is obtained by polymerizing a condensation product of (A) a polyalkoxypolysilane or (A') tetraalkoxysilane and (B) an unsaturated monomer containing at least one kind of functional group selected from a hydrolyzable silyl group or epoxy group with (C) an carboxyl-containing unsaturated monomer in an organic solvent, neutralizing the resultant, removing from the organic solvent system and adding water thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the stability of emulsions upon standing, the weather resistance, transparency, stain resistance, and water resistance of coating films.
It relates to a method for producing a silicon-containing aqueous coating composition having excellent solvent resistance and low odor (hereinafter abbreviated as a coating composition), and is particularly useful as a coating material for building material paints, adhesives, paper and the like. The present invention relates to a method for producing a novel coating composition.

[0002]

2. Description of the Related Art A resin into which an alkoxysilyl group is introduced by a polyalkoxypolysiloxane, a tetraalkoxysilane, an alkoxysilyl group (hydrolyzable silyl group) -containing monomer, or the like, has room-temperature curability and high hardness. Since it forms a coating film and has excellent properties such as weather resistance and stain resistance, it has been conventionally used as an adhesive, a binder for paint, and a paper coating agent.

For example, JP-A-6-145453 discloses an acrylic copolymer containing an alkoxysilyl group, a tetraalkylsilicate (tetraalkoxysilane) and / or
Or a condensate thereof, a hydrophilic curable composition comprising a curing catalyst is disclosed, and it is described that since the coating film surface becomes hydrophilic, contaminants can be washed away with rainwater or the like, and the stain resistance is effective. ing. In recent years, in the field of paints and adhesives, from the viewpoint of pollution control or resource saving, from the use of organic solvents, attempts have been made to convert the resin to a water-based or water-dispersible resin. The main focus is on polymerization in an organic solvent system. In an aqueous system, stable polymerization cannot be performed, and considerable technology is required to produce a target emulsion. Various attempts have been made for such aqueous polymerization. For example, as an example of emulsion polymerization using an alkoxysilyl group-containing monomer, JP-A-3-22731 is known.
No. 2 discloses an emulsion obtained by emulsion polymerization of an alkyl methacrylate, a monomer containing an alkoxysilane group, acrylamide and the like.
No. 354 discloses a reactive resin emulsion containing a resin having at least one hydrolyzable silyl group and one amine imide group in each molecule. Japanese Patent Application Laid-Open No. 10-77322 discloses a reaction for preparing a vinyl polymer using an acid group and a hydrolyzable silyl group in combination, and a polysiloxane obtained by hydrolyzing and condensing a silicon compound having a hydrolyzable group. And an aqueous resin obtained by neutralizing a composite resin obtained by performing the reaction in parallel in the same reaction system with a basic compound and then dispersing or dissolving it in water.

[0004] However, in the techniques disclosed in JP-A-3-227312 and JP-A-10-77322, although the weather resistance and the solvent resistance are improved to some extent, further improvements are required. With respect to the technology disclosed in Japanese Patent Application Laid-Open No. H10-77322, satisfactory results cannot be obtained with respect to emulsion stability, coating film transparency, odor and the like. The present inventors have conducted various studies.

[0005]

However, polymerization in an aqueous system using a polyalkoxypolysiloxane is difficult to stably exist in an aqueous medium, as described above, and is generally performed. Emulsion polymerization method, i.e., in the presence of an initiator by emulsifying and dispersing a part of the polyalkoxypolysiloxane and the polymerizable monomer in an aqueous medium,
The method of performing heat polymerization while charging the polyalkoxypolysiloxane and the polymerizable monomer has a disadvantage that the polyalkoxypolysiloxane cannot be stably introduced into the emulsion particles, and it is difficult to obtain a desired emulsion.

[0006]

The inventors of the present invention have conducted intensive studies in order to solve such a problem, and as a result, have found that polyalkoxypolysiloxane (A) or tetraalkoxysilane (A ') and hydrolyzable silyl can be used. A condensate of an unsaturated monomer (B) containing at least one functional group such as a hydroxyl group or an epoxy group with a carboxyl-containing unsaturated monomer (C) in an organic solvent; When the steps of neutralization, removal of the organic solvent from the system and addition of water to the system are carried out, the resulting coating composition was found to solve the above-mentioned problems, and the present invention was completed.

[0007]

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. The polyalkoxypolysiloxane (A) used in the present invention is not particularly limited as long as it is a compound represented by the following general formula (1).

[0008]

Embedded image In the formula, n is an integer having an average degree of condensation of 2 or more, and the compound may have fluidity at room temperature. R represents an alkyl group, an aryl group, or an aralkyl group (preferably an alkyl group). The carbon number of R may be the same or different, and may be linear or branched. The number of carbon atoms is preferably 1 to 10 (more preferably 1 to 5). As the above (A), specifically,
Polymethoxypolysiloxane, polyethoxypolysiloxane, polypropoxypolysiloxane, polybutoxypolysiloxane having n of 2 to 10 are mentioned, but after coating and drying, the stain resistance, water resistance and solvent resistance are short. In view of the above, polymethoxypolysiloxane and polyethoxypolysiloxane are preferred.

[0009] The tetraalkoxysilane (A ') used in the present invention is, specifically, tetramethoxysilane,
Tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane and the like are preferred, but tetramethoxysilane and tetraethoxysilane are preferred in that stain resistance, water resistance and solvent resistance are exhibited in a short time.

The method for producing (A) is not particularly limited, but is obtained by hydrolyzing (condensing) tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane. N in the general formula (1) can be adjusted by controlling the hydrolysis rate.

The hydrolysis reaction itself can be carried out by a known method. For example, room temperature is usually added to the above tetraalkoxysilane by adding a predetermined amount of water and distilling off by-product alcohol in the presence of an acid catalyst. It is possible by reacting at about 100 ° C. The degree of hydrolysis can be appropriately adjusted depending on the amount of water used, and the condensate may have fluidity.

Next, the unsaturated monomer (B) containing at least one functional group such as a hydrolyzable silyl group, hydroxyl group or epoxy group will be described in detail. Examples of the unsaturated monomer containing a hydrolyzable silyl group include γ- (meth) acryloxyethyltrimethoxysilane, γ- (meth) acryloxyethyltriethoxysilane, and γ- (meth) acryloxypropyltrimethoxysilane. 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) acryloxypropyltripropoxysilane, γ- (meth) acryloxypropylmethyldipropoxysilane, 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.

Of the above, γ- (meth) acryloxyethyltrimethoxysilane, γ- (meth) acryloxyethyltriethoxysilane, γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth)
Acryloxypropyltriethoxysilane, 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- (meta ) Acryloxydecyltrimethoxysilane, γ- (meth) acryloxydodecyltrimethoxysilane, γ- (meth) acryloxyoctadecyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinylmethyl It is a distearate silane.

As the unsaturated monomer having a hydroxyl group, 2-hydroxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate,
-Hydroxypropyl (meth) acrylate, ethyl carbitol acrylate, tripropylene glycol (meth) acrylate, 1,4-butylene glycol mono (meth) acrylate, 2-hydroxy-3-chloropropyl (meth) acrylate, glycerol mono (meth) A) acrylate, glycerol di (meth) acrylate, 2-hydroxyethyl acryloyl phosphate, 4-butylhydroxyacrylate, caprolactone-modified 2-hydroxyethyl acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, 2- Hydroxy-3-phenoxypropyl acrylate, 2-acryloyloxyethyl succinic acid, allyl alcohol, N-
Methylol (meth) acrylamide and the like, preferably 2-hydroxyethyl (meth) acrylate, 2
-Hydroxypropyl (meth) acrylate, N-methylol (meth) acrylamide, allyl alcohol.

The unsaturated monomers having an epoxy group include glycidyl (meth) acrylate, allyl glycidyl ether, N- [4 (2,3-epoxypropoxy) -3,5-dimethylbenzyl] acrylamide,
Examples thereof include bisphenol A diglycidyl ether mono (meth) acrylate, and preferred are glycidyl (meth) acrylate and allyl glycidyl ether.

In the present invention, the polyalkoxypolysiloxane (A) or the tetraalkoxysilane (A ') is combined with at least one of a hydrolyzable silyl group, hydroxyl group or epoxy group.
It is necessary to use a condensate (hereinafter abbreviated as a condensate) of the unsaturated monomer (B) containing a kind of functional group, and the condensate is the above (A) or (A ′) and (B) ) Is reacted in the presence of water and a catalyst, and then alcohol is distilled off.

The reaction weight ratio of (A) or (A ') to (B) is preferably 10/100 to 100/1, and more preferably 50/100 to 100/1.
/ 100 to 100/10. If it is less than 10/100, the stain resistance, weather resistance, solvent resistance, and water resistance when coated become insufficient, and if it exceeds 100/1, the weather resistance, water resistance, and solvent resistance when the coating agent composition is formed. And the odor due to the low molecular weight component (A) may be increased, which is not preferable. Water is used in an amount of 0.1 to 100 parts by weight of the total amount of (A) or (A ') and (B).
It is 1 to 50 parts by weight, further 0.5 to 30 parts by weight.
If the amount is less than 0.1 part by weight, the condensation between (A) or (A ') and (B) becomes insufficient. If the amount exceeds 50 parts by weight, the viscosity becomes high, and the solubility in unsaturated monomers also decreases. Not preferred.

The catalyst used for the condensation may be any compound having an acid functional group which is soluble in (A) or (A ') or (B). The acid functional group may be a carboxylic acid group or a sulfonic acid group. And inorganic acids, organic acids, monomers and polymers containing a phosphoric acid group. Specific examples of the catalyst include p-toluenesulfonic acid, sulfuric acid, formic acid, acetic acid, phosphoric acid and the like, and the blending amount of the catalyst is (A) or the total amount of (A ') and (B) is 100. It is 0.1 to 20 parts by weight, more preferably 0.3 to 10 parts by weight based on parts by weight. If the amount is less than 0.1 part by weight, the condensation reaction may take a long time or the condensation reaction may not proceed. If the amount is more than 20 parts by weight, the stability during polymerization is reduced, or the water resistance when coated is reduced. Not preferred. In addition, alcohol or the like may be used as a diluting solvent during the reaction.

The reaction temperature of the condensation is preferably from 0 to 100 ° C., more preferably from 10 to 80 ° C., and the reaction time is preferably from 0.5 to 50 hours, more preferably from 1 to 40 hours.

After the condensation reaction, when an alcohol is formed as a by-product of the condensation or when an alcohol is used as a diluting solvent, the alcohol is heated to 30 to 150 ° C. (preferably 30 to 150 ° C.).
(About 50 ° C.) under reduced pressure or normal pressure to a concentration of 5% by weight or less (preferably 1% by weight or less).

If necessary, the remaining acid functional group-containing compound is neutralized with a base such as ammonia or diethylamine.
The base is added as an aqueous solution or used as an alcohol solution or a mixed solution of water / alcohol.

Next, the carboxyl group-containing unsaturated monomer (C) will be described. The carboxyl group-containing unsaturated monomer includes (meth) acrylic acid, crotonic acid, fumaric acid, (anhydride) maleic acid, itaconic acid, citraconic acid,
Ricinoleic acid and salts thereof (amine salts, sodium salts, potassium salts), and partial esters thereof, and the like are mentioned, and (meth) acrylic acid is preferable.

It is preferable to use other unsaturated monomers in addition to the above components.
Although it is not particularly limited as long as it has radical polymerizability, specifically, styrene, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate,
Isobutyl (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, acryl chloride, acetoacetylated (meth) acrylate, (meth) acrylamide, 1,1,1-trimethylamine methacrylimide, 1,1-dimethyl-1-ethylamine methacrylimide, 1,1-dimethyl-1 -(2-hydroxypropyl) 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, Alternatively, monomers represented by the following formulas (2) and (3) may be mentioned.

[0024]

Embedded image

[0025]

Embedded image Further, there may be mentioned unsaturated monomers containing at least one functional group such as the above-mentioned hydrolyzable silyl group, hydroxyl group or epoxy group.

The above unsaturated monomers are used alone or in a mixture of two or more. Among them, styrene, methyl (meth) acrylate, ethyl acrylate, n-butyl (meth) acrylate, 2-ethylhexyl Acrylates are preferred.

In producing the composition of the present invention,
The condensate and the carboxyl group-containing unsaturated monomer (C) are polymerized in an organic solvent, and the polymerization initiator used in the polymerization is an oil-soluble polymerization initiator. t-butyl hydroperoxide, cumene hydroperoxide, p-methane hydroperoxide, isobutyl peroxide, lauryl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, t-butyl cumyl peroxide Oxide, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide,
Di-t-butyl peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, di-isobutyl peroxide Organic peroxides such as oxydicarbonate, di-2-ethylhexylperoxydicarbonate, t-butylperoxyisobutyrate, azobisisobutyronitrile, dimethylazodiisobutyrate, 2,
2-azobis (2,4-dimethylvaleronitrile),
2,2-azobis (2-methylbutyronitrile) and the like. The polymerization initiator may be added to the polymerization vessel in advance, may be added immediately before the start of polymerization, or may be added to the mixture of the condensate and (C) in advance. When a condensate, (C), and other unsaturated monomers are used, the polymerization initiator is used in an amount of 0.0
It is preferably 3 to 2 parts by weight, more preferably 0.05 to 1 part by weight.
When the amount of the polymerization initiator is less than the above range, the polymerization rate becomes slow, and when the amount exceeds the above range, the solvent resistance and weather resistance at the time of coating may decrease, which is not preferable. Also,
For the purpose of adjusting the molecular weight during polymerization, a small amount of a chain transfer agent such as thiols (1-dodecanethiol, etc.), mercaptans, etc. may be used.

The mixing ratio of the condensate and (C) is preferably condensate / (C) = 75 to 95/25 to 5 (weight ratio). Outside the above range, the storage stability of the coating agent composition is lowered, and when coated, weather resistance, solvent resistance, and stain resistance cannot be obtained, which is not preferable.

Examples of the organic solvent used above include alcohols such as methanol, ethanol and isopropanol, and ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone. Preferred are alcohols such as methanol and isopropanol.

When the condensate, (C) and other unsaturated monomers are used, the organic solvent is used in an amount of 50 to 400 parts by weight, preferably 7 to 100 parts by weight, inclusive.
The amount is preferably from 0 to 200 parts by weight, and if it is less than 50 parts by weight, the reaction solution has a high viscosity, and if it exceeds 400 parts by weight, a large amount of the organic solvent needs to be distilled off, which is not preferable.

As the above polymerization method, a condensate, (C),
The mixture containing the entire amount of the organic solvent is heated and polymerized as it is. A part of the mixture comprising the condensate, (C) and the organic solvent is heated to initiate polymerization, and the remaining mixture is added dropwise. After the temperature is increased by charging the organic solvent in the reaction vessel, the total amount of the condensate and the (C) is (continuously) dropped or dividedly charged to carry out the polymerization. Is preferred in that the control of the polymerization is easy and the polymerization stability is good.

[0032] The polymerization conditions are preferably in the range of usually about 40 to 90 ° C, and the reaction is completed in about 1 to 8 hours after the start of the temperature rise. As the polymerization conditions, 5 to 50% by weight of a mixture of the condensate, (C) and the organic solvent is polymerized at 40 to 90 ° C. for 0.1 to 4 hours, and the remaining mixture is mixed for about 1 to 5 hours. Then, the mixture is aged at the same temperature for about 1 to 3 hours. As the polymerization conditions, the organic solvent charged in the reaction vessel is 40 to 90 ° C.
And a mixed solution composed of the condensate, (C) and the organic solvent is continuously added dropwise over a period of about 2 to 5 hours, or dividedly charged and reacted for a total of 2 to 5 hours. Aged for about an hour.

Next, a step of neutralizing, a step of removing the organic solvent, and a step of adding water to the system together therewith are performed. The order of each step is not particularly limited, but specifically,
(A) a method of removing the organic solvent after the step of neutralizing and adding water, (b) a method of removing the organic solvent and performing a step of neutralizing and adding water, (c) after the neutralization And a method of simultaneously performing the step of removing the organic solvent and the step of adding water (removing the organic solvent while adding water), and the like, and the methods (a) and (b) are particularly preferable.

The carboxyl group in the copolymer is neutralized by adding a basic compound to the system. As the basic compound, ammonia, N, N-dimethylethanolamine, diethylamine, triethylamine, morpholine, 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, etc., and preferably, ammonia and diethylamine are 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 to 110% per equivalent of carboxyl group and added while stirring. Neutralize.
The neutralization is performed until the pH of the system becomes 4 to 10, preferably 5 to 9. If the pH is less than 4 or more than 10, the storage stability of the coating composition is undesirably reduced.

When water is used, the total amount of the condensate, (C) and other unsaturated monomers, if used, is 100
50 to 500 parts by weight, and more preferably 100 to 500 parts by weight
The amount is preferably 300 parts by weight, and if it is less than 100 parts by weight, the viscosity of the aqueous emulsion becomes high, and the concentration of the resulting aqueous emulsion exceeding 500 parts by weight is undesirably low. It is preferable that water is added gradually at usually about 10 to 80 ° C. while mixing with a stirring blade.

The organic solvent is removed under normal pressure or reduced pressure, and is usually removed until the residual amount becomes 5% by weight or less, preferably 1% by weight or less of the whole system.

The composition of the present invention may contain known defoaming agents, preservatives, rust preventives, ultraviolet absorbers, antioxidants, etc. as long as the effects of the present invention are not impaired. Further, in order to accelerate the curing of the coating film, a curing agent such as an organotin compound such as an organotin compound or an organoaluminum compound may be added, and the curing agent may be added in the form of an emulsion.

The particle size of the emulsion in the coating composition obtained above is 30 to 1000 nm, which is excellent in storage stability, and furthermore, has film forming properties, adhesion, chemical resistance, transparency, gloss, It is excellent in water resistance, weather resistance, stain resistance, etc., and is useful as a coating agent for building material paints, adhesives, paper, and the like.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below.
In the following description, “%” and “parts” mean “% by weight” and “parts by weight”. Example 1 In a flask equipped with a condenser, a thermometer, and a stirring blade, 25 parts of polyethoxypolysiloxane [Ethylsilicate 40, manufactured by Colcoat Co., Ltd.] (A), 10 parts of γ-methacryloxypropyltrimethoxysilane (B), 0.94 water
And 0.3 part of formic acid were reacted at room temperature for 30 hours, and then by-produced ethanol and formic acid were distilled off under reduced pressure at 40 ° C. to obtain a condensate (ethanol content 0.5%). On the other hand, 150 parts of isopropyl alcohol was charged into a flask equipped with a condenser, a thermometer, and a stirring blade, and the temperature was raised to 80 ° C. Next, 35 parts of the above condensate, 5 parts of acrylic acid (C), 47 parts of methyl methacrylate, 34 parts of n-butyl acrylate,
Polymerization was carried out while dropping a mixture of 2.0 parts of 1-dodecanethiol and 0.5 parts of azobisisobutyronitrile over 3 hours at 80 ° C., and after dropping, further polymerization at 80 ° C. for 2 hours. 0.3 parts of bisisobutyronitrile was added, and the polymerization was further continued for 2 hours. Then 28% with stirring
2.8 parts of aqueous ammonia and 298 parts of water were added at room temperature, and isopropyl alcohol was distilled off under reduced pressure at 50 ° C. or lower to obtain a coating composition in the form of emulsion, and the following properties were measured.

(Average Particle Size) The average particle size of the emulsion was measured using a laser light scattering particle size analyzer DLS- manufactured by Otsuka Electronics Co., Ltd.
Measured at 700. (Non-volatile content) The non-volatile content was measured under the conditions according to JIS K6828. (Viscosity) The viscosity was measured at 25 ° C. using a rotational viscometer and conditions according to JIS K7117. (PH value) The pH value was measured using a pH meter based on JIS Z8802. (Coarse particle amount) 100 m of the obtained coating agent composition
The resulting mixture was filtered through an ash wire mesh, and the residue was dried at 105 ° C. for 1 hour. The weight of the coarse particles obtained was indicated by weight based on 100 g of the composition. (Amount of residual alcohol) After the obtained coating agent composition was centrifuged, the aqueous layer was subjected to 163 manufactured by Hitachi, Ltd.
The residual alcohol content was measured using a type FID gas chromatography.

Next, with respect to the above coating composition,
The following evaluation was performed. (Odor) The odor of the obtained coating composition was examined.・ ・ ・: Almost none △: slight ×: strong odor (Stability to stand) The obtained coating composition was left at room temperature for 3 months, and the state was visually observed. ○ ・ ・ ・ No change △ ・ ・ ・ Slight viscosity increase × ・ ・ ・ Viscosity increase or gelation

Further, the obtained coating composition was cast with an applicator so as to have a thickness of 100 μm and dried at room temperature for 7 days to prepare a coating film, and the following transparency, weather resistance, stain resistance, and the like were obtained. Water resistance and solvent resistance were evaluated. (Transparency) The transparency of the coating film was visually observed.・ ・ ・: Transparent film Δ: slight cloudiness was observed. X: An opaque cloudy film. (Weather resistance) An outdoor exposure test (place: Ibaraki City, Osaka Prefecture) of the above coating film was performed for one year, 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.

(Stain resistance) The above coating film was subjected to an outdoor exposure test (location: Ibaraki City, Osaka Prefecture) for one year, and the rain streaks of the coating film were visually observed. ◎ ・ ・ ・ rain lines are hardly recognized. ○: Rain lines were slightly observed in some areas. Δ: Rain lines were observed in some places. X: Rain streaks were clearly observed on the entire surface. (Water resistance) The surface condition after immersing the coating film in distilled water for 24 hours 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 surface state of the above coating film after immersion in ethyl acetate for 24 hours 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.

Example 2 The procedure of Example 1 was repeated, except that 10 parts of 2-hydroxymethacrylate (B) was used in place of 10 parts of γ-methacryloxypropyltrimethoxysilane (B) used to produce the condensate. The coating composition was obtained, and the properties were measured and evaluated in the same manner as in Example 1.

Example 3 Instead of 10 parts of γ-methacryloxypropyltrimethoxysilane (B) used in producing the condensate in Example 1, 10 parts of glycidyl methacrylate (B) was used.
In the same manner, a coating agent composition was obtained, and the properties were measured and evaluated in the same manner as in Example 1.

Example 4 Polymethoxypolysiloxane [Mitsubishi Chemical Co., Ltd.] was used instead of the polyethoxypolysiloxane [Ethylsilicate 40] (manufactured by Colcoat Co., Ltd.) (A) used in producing the condensate in Example 1. MS51] (A), except that the same amount was used, to obtain a coating composition.
The properties were measured and evaluated in the same manner as described above.

Example 5 The same amount of tetraethoxysilane (A) was used in place of the polyethoxypolysiloxane [Ethylsilicate 40, manufactured by Colcoat Co., Ltd.] (A) used in producing the condensate in Example 1. The procedure was the same as in Example 1, except that water was changed to 2 parts, and a coating composition was obtained. The properties were measured and evaluated in the same manner as in Example 1.

Example 6 2.8% of 28% ammonia water used in Example 1 for neutralization
Parts, and 298 parts of water, instead of 7 parts of triethylamine and 282 parts of water, a coating composition was obtained, and properties were measured and evaluated in the same manner as in Example 1.

Comparative Example 1 150 parts of isopropyl alcohol was charged into a flask equipped with a condenser, a thermometer, and a stirring blade, and the temperature was raised to 80.degree. Next, 25 parts of polyethoxypolysiloxane [manufactured by Colcoat Co., Ltd., ethyl silicate 40] (A), γ-
Methacryloxypropyltrimethoxysilane (B) 10
Parts, acrylic acid (C) 5 parts, methyl methacrylate 47
, 34 parts of n-butyl acrylate, 2 parts of 1-dodecanethiol, and 0.5 part of azobisisobutyronitrile were dropwise added at 80 ° C. over 3 hours to polymerize the mixture.
After polymerization at 80 ° C. for 2 hours, 0.3 parts of azobisisobutyronitrile was added, and polymerization was continued for another 2 hours. Then
While stirring, 2.8 parts of 28% ammonia water and 298 parts of water were added at room temperature, and isopropyl alcohol was further added at 50 ° C.
The solvent was distilled off under reduced pressure to obtain an emulsion-like coating composition. The properties of the composition were measured and evaluated in the same manner as in Example 1.

Comparative Example 2 Water 2 was added to a flask equipped with a condenser, a thermometer, and a stirring blade.
98 parts, 3 parts of an alkylphenol ether-based reactive emulsifier (SE-10N, manufactured by Asahi Denka Co., Ltd.) were charged, and
After the temperature was raised to 35 ° C., 35 parts of the condensate obtained in Example 1, 5 parts of acrylic acid (C), 47 parts of methyl methacrylate, n
-Butyl acrylate 34 parts, 1-dodecanethiol 2
Of a mixture of 0.5 part of azobisisobutyronitrile with 8 parts of
The polymerization was carried out dropwise at 0 ° C. for 3 hours, but the polymerization was stopped because of gelation during the polymerization. Table 1 shows the measurement results of Example and Comparative Example 1, and Table 2 shows the evaluation results.

[0052]

[Table 1] Non-volatile viscosity pH average Coarse residue (%) (cps) Particle size Alcohol amount (nm) (g / 100g) (%) Example 1 29 15 8 80 0.1 0.3 Example 2 30 20 8 85 0.2 0.2 Example 3 29 30 8 87 0.2 0.1 Example 4 29 20 8 78 0.2 0.2 Example 5 27 15 8 60 0.2 0.5 Example 6 32 92 8 77 0.1 0.1 Comparative example 1 27 18 8 2000 150 0.5

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[Table 2] Odor storage Transparency Weather resistance Stain resistance Water resistance Solvent resistance Stability Example 1 ○ ○ ◎ ◎ ◎ ◎ ◎ Example 2 ○ ○ ◎ ○ ◎ ○ ○ Example 3 ○ ○ ◎ ○ ◎ ◎ ○ Example 4 ○ ○ ◎ ◎ ◎ ◎ ◎ Example 5 ○ ○ ◎ ○ ◎ ◎ ○ Example 6 ○ ○ ◎ ◎ ◎ ○ ◎ Comparative Example 1 × △ × △ △ ○ △

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According to the present invention, an unsaturated monomer containing a polyalkoxypolysiloxane (A) or tetraalkoxysilane (A ') and at least one functional group such as a hydrolyzable silyl group, a hydroxyl group or an epoxy group is used. A step of polymerizing a condensate with (B) and a carboxyl group-containing unsaturated monomer (C) in an organic solvent, and then neutralizing, removing the organic solvent from the system, and adding water to the system. The resulting aqueous coating composition is excellent in emulsion storage stability, coating weather resistance, transparency, stain resistance, water resistance and solvent resistance.

 ──────────────────────────────────────────────────の Continuing on 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. 4J027 AC03 AC04 AC06 AC09 AF03 AF04 AF05 AF06 BA02 BA04 BA05 BA06 BA07 BA10 BA12 BA13 BA14 CA10 CB03 CB09 CC02 CD08 CD09 4J038 CL001 DL051 GA03 GA07 GA15 JC32 KA03 KA06 MA08 MA10 MA14 NA03 NA04 NA05 NA26 PB05 PC06 PC10

Claims (1)

[Claims] 1. A polyalkoxypolysiloxane (A) or tetraalkoxysilane (A ′) and an unsaturated monomer (B) containing at least one functional group of a hydrolyzable silyl group, hydroxyl group or epoxy group. And the carboxyl group-containing unsaturated monomer (C) is polymerized in an organic solvent, followed by neutralization, removal of the organic solvent from the system and addition of water to the system. A method for producing a silicon-containing aqueous coating composition, which is characterized by the following.