JP2002371223A - Aqueous inorganic coating material composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous inorganic coating material composition which enables the formation of a flat coating film having excellent flame retardance, weatherability, and crack resistance. SOLUTION: In an aqueous inorganic coating material composition, at least one inorganic flatting agent to be selected from the group consisting of an aqueous colloidal silica and a potassium titanate whisker is incorporated into an acrylic silicone resin emulsion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an aqueous inorganic coating composition. According to the present invention, it is possible to provide a matte coating film having excellent flame retardancy.

[0002]

2. Description of the Related Art
As a paint used for the matte coating film, there is known one in which a matting agent such as an aqueous dispersion of silica or olefin is mixed with an acrylic resin, a urethane resin, or an acryl-urethane resin. In addition, water-based paints using water as a medium have been widely used in recent years from the viewpoint of working environment and safety. However, when the aqueous coating composition comprising such an acrylic resin is further examined, it has been found that there is a problem in the flame retardancy, crack resistance, weather resistance, and the like of the coating film when a matte coating film is formed. .

[0003] The present invention has been made in view of the above problems, and an object of the present invention is to provide an aqueous inorganic coating composition capable of forming a matte coating film having excellent flame retardancy. is there.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have found that a water-based paint made of an acrylic silicone resin emulsion is added to a water-based colloidal silica and a potassium titanate whisker. It has been found that the incorporation of at least one inorganic matting agent selected from the group can form a matte coating film having excellent flame retardancy, and completed the present invention.

That is, the present invention relates to an aqueous inorganic coating composition containing an acrylic silicone resin emulsion and at least one compound selected from the group consisting of aqueous colloidal silica and potassium titanate whiskers.

[0006]

DETAILED DESCRIPTION OF THE INVENTION As described above, the aqueous inorganic coating composition of the present invention comprises an acrylic silicone resin emulsion blended with aqueous colloidal silica, a potassium titanate whisker blended, and an aqueous colloidal silica blend. And potassium titanate whiskers.

The term "acrylic silicone resin emulsion" as used herein means 30 to 70% by weight, preferably 40% by weight.
Refers to a substantially organic solvent-free emulsion resin in which 〜60% by weight of an acrylic resin is hybridized with 70 to 30% by weight, preferably 60 to 40% by weight of a silicone resin. The term “hybridization” refers to a state in which an acrylic resin and a silicone resin are mutually intermingled (coexist) in a micro structure to form a network structure, that is, an interpenetrating network structure (IPN). Here, if the amount of the silicone resin in the acrylic silicone resin is less than 30% by weight, weather resistance and stain resistance are reduced, while if it is more than 70% by weight, crack resistance is deteriorated.

The method for producing the acrylic silicone resin of the present invention may be in accordance with the method described in Japanese Patent Application Laid-Open No. 10-183064.
A hydrolyzable silane compound such as an organoalkoxysilane is hydrolyzed and condensed to form a silicone resin, the obtained silicone resin is dissolved in an acrylic monomer, and then the polymerization of a mixed solution containing a silicone resin-containing acrylic monomer solution is performed. By doing so, an acrylic silicone resin can be obtained.

[0009] The silicone resin of the present invention is preferably a silicone compound having a water-insoluble silanol group. Specifically, the silicone resin is obtained by hydrolyzing a hydrolyzable silane compound under the following production conditions. be able to.

As a method for producing a silicone resin having a silanol group, there is a method in which a hydrolyzable silane compound is hydrolyzed in an organic solvent, followed by a dehydration condensation reaction. At this time, it is necessary to select an organic solvent that can dissolve the hydrolyzable silane compound and the obtained silicone resin. Generally, aromatic hydrocarbons such as toluene and xylene, and methyl ethyl ketone And ketone solvents such as methyl isobutyl ketone, ester solvents such as ethyl acetate, isobutyl acetate and butyl acetate, and alcohols such as methanol, ethanol, isopropanol, butanol, isobutanol and t-butanol. In addition, two or more kinds of organic solvents can be used as a mixture. The silicone resin is obtained as a solvent-free viscous liquid or solid by distilling off an organic solvent and a by-produced alcohol under reduced pressure by heating.

In carrying out the hydrolysis, a hydrolysis catalyst may be used. As the hydrolysis catalyst, ordinary acidic hydrochloric acid, nitric acid, sulfuric acid, acetic acid, maleic acid, methylsulfonic acid and the like are used. From the viewpoint that the hydrolysis catalyst can be easily removed after the hydrolysis, it is preferable to use hydrochloric acid as the hydrolysis catalyst. The amount of the hydrolysis catalyst is preferably in the range of 0.001 to 1 mol% based on 1 mol of the hydrolyzable group in the hydrolyzable silane compound. When the amount of the hydrolysis catalyst is 0.0
If it is less than 01 mol, the hydrolysis rate may not be sufficient, and if it is 1 mol or more, the reactivity,
The properties of the coating film may be adversely affected.

Subsequently, examples of the hydrolyzable silane compound used for producing the silicone resin include vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane,
Hexenyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- (meta ) Acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 4-vinylphenyltri Methoxysilane, 3- (4-vinylphenyl) propyltrimethoxysilane, 4-vinylphenylmethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyl Silane, 3-aminopropyl methyl diethoxy silane, 3- (2-aminoethyl)
Aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane , Methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltributoxysilane, methyltriisopropenoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiisopropoxysilane, dimethyldibutoxysilane, dimethyl Diisopropenoxysilane, trimethylmethoxysilane, trimethylethoxysilane, trimethylisopropenoxysilane, ethyltrimethoxy Silane, butyltrimethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, phenyltrimethoxysilane, cyclohexyltrimethoxysilane, propylmethyldimethoxysilane, hexylmethyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldimethoxysilane, and parts thereof Examples include, but are not limited to, hydrolysates.

It is more preferable to use methoxy silane or ethoxy silane from the viewpoint that removal of by-products and operability are easy. These hydrolyzable silane compounds may be used alone or in combination of two or more.

Next, the acrylic monomer will be described. The acrylic monomer is not particularly limited as long as it is capable of radical polymerization.Examples include acrylic acid or methacrylic acid methyl, ethyl, propyl, isopropyl, butyl, isobutyl, octyl, 2-ethylhexyl, lauryl, stearyl, or stearyl. Having an alkyl group having 1 to 18 carbon atoms such as cyclohexyl ester (meth)
Acrylic acid alkyl ester; carboxyl group or its anhydride-containing vinyl monomer such as acrylic acid, methacrylic acid, maleic anhydride; 2-hydroxyethyl (meth)
Hydroxyl group-containing vinyl monomers such as acrylate and 2-hydroxypropyl (meth) acrylate; (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide,
Amide group-containing vinyl monomers such as N-butoxymethyl (meth) acrylamide and diacetone (meth) acrylamide; amino group-containing vinyl monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; methoxyethyl (meth)
Conventionally known monomers such as vinyl monomers containing an alkoxy group such as acrylate and butoxyethyl (meth) acrylate; and vinyl monomers containing a glycidyl group such as glycidyl (meth) acrylate and glycidyl allyl ether can be used. These monomers may be used alone or in combination of two or more.

In the present invention, in addition to the above monomers, vinyl ester monomers such as vinyl acetate and vinyl propionate; aromatic vinyl monomers such as styrene, vinyl toluene and α-methylstyrene; and (meth) acrylonitrile and the like. Vinyl cyanide monomers; vinyl halide monomers such as vinyl chloride and vinyl bromide; divinylbenzene, allyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate Vinyl monomer containing two or more radically polymerizable unsaturated groups in one molecule; (poly) oxyethylene chain such as (poly) oxyethylene mono (meth) acrylate having 1 to 100 ethylene oxide groups Including Vinyl monomers; at one end (meth)
A dimethylpolysiloxane containing an acryloxypropyl group, a dimethylpolysiloxane containing a styryl group or an α-methylstyryl group at one end, a radically polymerizable functional group at one end, and a siloxane unit of 1 to 200
Diorganopolysiloxanes; vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, 5-hexenyltrimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- ( (Meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 4-vinylphenyltrimethoxysilane, 3- (4-vinylphenyl) A compound such as a silane compound having a radical polymerizable functional group such as propyltrimethoxysilane or 4-vinylphenylmethyltrimethoxysilane may be contained as a comonomer in an amount of 0.1 to 40% by weight based on all monomers.

In the above-mentioned monomers, it is preferable to use an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms in an amount of 1 to 100% by weight based on all monomers. If the content is less than 1% by weight, sufficient chemical resistance may not be obtained. More preferably, an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms is used in an amount of 30 to 99% by weight based on all monomers.
It is preferable to be within the range.

As described above, the acrylic silicone resin emulsion of the present invention is produced by a polymerization reaction of a solution in which a silicone resin is dissolved in an acrylic monomer.
Specifically, it contains the water-insoluble silanol group-containing silicone resin and an acrylic monomer as main components,
It can be produced by emulsion polymerization of a solution containing substantially no organic solvent.

Here, a radical polymerization initiator is used in the emulsion polymerization. As the radical polymerization initiator, water-soluble potassium persulfate, ammonium persulfate, aqueous hydrogen peroxide, t-butyl hydroperoxide and the like are used. In addition, redox-based initiators such as benzoyl peroxide and azoisobutyronitrile, which are oil-soluble initiators, and a reducing agent such as sodium acid sulfite and ascorbic acid may be used. The polymerization initiator may be used in an amount of 0.1 to 10% by weight, and preferably 0.5 to 5% by weight, based on the acrylic monomer.

Further, in order to improve the stability of the emulsion, it is preferable to adjust the inside of the system to pH 3 to 9.
When the pH range is lower than pH 3 or higher than pH 9, the surfactant used for emulsion polymerization may become unstable or silanol groups may be easily condensed. It is more preferable to control the pH to 4 to 8.

Next, the aqueous colloidal silica used as a matting agent in the present invention will be described. The aqueous colloidal silica referred to here is a silica sol supplied in a form in which negatively charged amorphous silica particles are colloidally dispersed in water, and has a spherical average particle diameter of 1 to 100 nm. Specifically, Adelite (registered trademark) series (manufactured by Asahi Denka Kogyo), Cataroid (registered trademark) series (manufactured by Kasei Kasei Kogyo), Snowtex (registered trademark) series (manufactured by Nissan Chemical Industries), etc. Can be used. However, the pH of the colloidal silica dispersion is
Is less than 3, when mixed with an aqueous emulsion, the resin component is adsorbed and aggregates are easily formed, and the pH is 10
If the pH exceeds 3, the stability of the emulsion after mixing with the aqueous emulsion is liable to decrease, so the pH of the colloidal silica dispersion is preferably 3 to 10, more preferably 7 to 10.
Is more preferable. In the present invention, these aqueous colloidal silicas can be used alone or in combination of two or more.

Here, in the present invention, it is preferable to add a metal carboxylate to the aqueous colloidal silica. This is because, when the metal carboxylate is added to the aqueous colloidal silica, the aqueous colloidal silica is crosslinked.
This is because the strength of the obtained coating film can be improved. The carboxylic acid in the carboxylic acid metal salt includes oxalic acid, acetic acid, malic acid, tartaric acid, hydroxyacetic acid, acrylic acid, methacrylic acid, lactic acid, octylic acid, formic acid, benzoic acid, gluconic acid, glutamic acid, salicylic acid, and the like. Examples of the metal include sodium, potassium, lithium, beryllium, magnesium, calcium, strontium, iron, cobalt, nickel, zinc,
Manganese, copper, cadmium, lead, bismuth, barium,
Examples include antimony and zirconium. The preferred metal carboxylate in the present invention is an alkali metal monocarboxylate, and particularly preferred are sodium acetate and potassium acetate.

The amount of the metal carboxylate added is usually 0.1 to the silica content (solid content) of the aqueous colloidal silica.
It is 5 to 20% by mass, preferably 1 to 10% by mass. When the addition amount of the metal carboxylate is too small, the cross-linking of the colloidal silica is insufficient, so that the coating strength tends to decrease. Since the reaction is promoted, the strength of the coating film tends to decrease.

Next, another matting agent used in the present invention, potassium titanate, will be described. Potassium titanate is a crystalline synthetic inorganic compound (polycrystal) represented by the general formula: K ₂ O · nTiO ₂ (n is an integer). The chemical composition can be appropriately selected according to the purpose and use of the coating film. For example, potassium dititanate [K ₂ Ti ₂ O ₅ ] and potassium tetratitanate [K ₂ Ti ₄ O ₉ ], potassium hexatitanate [K ₂ Ti ₆ O ₁₃ ] and potassium octa titanate [K ₂ Ti ₈ O ₁₇ ] having a tunnel structure can be used.
Among these, potassium hexatitanate and potassium octa titanate are preferable because they have high thermal stability and can exert a good coating film reinforcing effect even in a high temperature range. These potassium titanates may be used alone or in combination of two or more.

The potassium titanate may be in the form of a flake, a fiber, or a whisker. In the present invention, the whisker-like (potassium titanate whisker) may be used. preferable. Such a potassium titanate whisker is a needle-like crystal fiber, has a large specific surface area, and is excellent in heat insulation, heat resistance, chemical resistance, etc., and thus improves the durability, heat resistance and physical properties of the coating film. It is possible to do. At the same time, potassium titanate whiskers can obtain a good matting effect because they are oriented on the coating film surface.

The potassium titanate whisker has a fiber length of 1 to 50 μm, more preferably 10 to 20 μm.
It is preferable to use one having a fiber diameter of 0.1 to 1.0 μm, more preferably 0.3 to 0.6 μm. In particular, potassium titanate whiskers having a fiber length and a fiber diameter within the above ranges and an aspect ratio (fiber length / fiber diameter) of 8 or more have a remarkable coating film reinforcing effect, and It has a great effect on improving performance.

As the potassium titanate used in the present invention,
Specifically, TISMO (registered trademark) N (manufactured by Otsuka Chemical,
Potassium hexatitanate whisker) and TISMO (registered trademark) D (potassium octa titanate whisker, manufactured by Otsuka Chemical Co., Ltd.).

The aqueous inorganic coating composition of the present invention may further comprise, if necessary, a pigment, a dye, a polyurethane,
Acrylic resin, polyester, polyolefin, polyamide, rubber and other resin-based emulsions, suspensions, dispersions, aqueous solutions, water for adjusting solid content and viscosity, isopropanol and N- for adjusting surface tension
Organic solvents such as methylpyrrolidone, preservatives, fungicides, antibacterial agents, antiblocking agents, dispersion stabilizers, thixotropic agents, antioxidants, ultraviolet absorbers, defoamers, thickeners, film forming aids , Surfactants, fillers, catalysts, lubricants, antistatic agents, plasticizers, leveling agents, anti-gelling agents, light stabilizers,
It can be obtained by blending an antistatic agent and the like and using a ball mill, a sand grind mill and the like.

The aqueous inorganic coating composition of the present invention includes:
Further, titanium oxide which is a photoreaction catalyst can be added. By adding such a photoreaction catalyst, the durability and stain resistance of the coating film can be improved. When a photoreaction catalyst is added to a conventional organic coating material, it causes deterioration of the resin itself in the coating material. Therefore, it is not preferable to add the photoreaction catalyst to the organic coating material. Also,
Since the aqueous inorganic coating composition of the present invention has a higher silica content than conventional aqueous acrylic coatings, aqueous urethane coatings, and aqueous acrylic-urethane coatings, it is possible to easily disperse titanium oxide as a photoreaction catalyst. is there. The coating film further containing the photoreaction catalyst decomposes acidic substances (nitrogen oxides and sulfur oxides) in the air attached to the coating film surface, thereby extending the life of the coating film and contaminating it. The prevention effect can be improved.

The amount of the matting agent (aqueous colloidal silica and / or potassium titanate whisker) in the aqueous inorganic coating composition of the present invention can be appropriately determined according to the use and purpose of the coating film. However, in order to further improve the crack resistance in addition to the improvement in the flame retardancy of the coating film, it is preferable that the value of the matting agent (solid content) / the resin component (solid content) be in the following range.

First, regarding aqueous colloidal silica,
The content is preferably 5 to 60% by weight (solid content), more preferably 10 to 40% by weight, based on the acrylic silicone resin component (solid content) in the aqueous inorganic coating composition. When the content of the aqueous colloidal silica is out of the above numerical range, the crack resistance of the coating film may be deteriorated, and the content (solid content) of the aqueous colloidal silica may be lower than the resin solid content in the acrylic silicone resin emulsion. If the content is more than 60% by weight, the film-forming property is reduced and cracks are easily caused.

The content of the potassium titanate whisker is preferably 5 to 60% by weight, more preferably 10 to 40% by weight, based on the acrylic silicone resin component (solid content) in the aqueous inorganic coating composition. is there. The potassium titanate whisker has a great effect on the cracking of the coating film. If the amount is outside the above numerical range, the crack resistance of the coating film may be deteriorated. Also,
If it is more than 60% by weight, the film formability, workability and physical properties of the coating film may be deteriorated. On the other hand, if it is less than 5% by weight, the coating film may not be able to exhibit a sufficient matting effect.

Further, when aqueous colloidal silica and potassium titanate whisker are used together as a matting agent, the total amount of both is 5 to 60 with respect to the acrylic silicone resin component (solid content) in the aqueous inorganic coating composition. weight%
(Calculated as the amount of solid content for aqueous colloidal silica), more preferably 10 to 40.
Weight percent (calculated as the amount of solids for aqueous colloidal silica).

The coating composition of the present invention may be either a one-pack type or a two-pack type. In the case of a two-pack type, at the time of construction, aqueous colloidal silica (and / or potassium titanate whisker) is added to the acrylic silicone resin paint, and if necessary, water is added, and a hand mixer or the like is used. To mix. In addition, when using potassium titanate whisker, it can be generally used as a one-pack type paint, but when using aqueous colloidal silica, it is preferable to use a two-pack type paint from the viewpoint of storage stability and the like. . The method for producing the water-based coating composition of the present invention is not particularly limited. For example, a water-based colloidal silica and / or potassium titanate whisker as a matting agent is added to a coating made of an acrylic silicone resin emulsion. And the like.

The water-based coating composition of the present invention is preferably used as a coating material for building materials. The material to be coated may be concrete, cement-based substrate, calcium silicate plate, other ceramic substrate, aluminum, iron , A metal substrate such as stainless steel, glass, wood, paper and the like. Also,
Examples of the coating method include usual coating methods such as brush coating, spray coating, roller coating, and dip coating.

[0035]

The present invention will be described below in more detail, but the present invention is not limited to these examples.

<Example 1> Water 1 was added to a mixing vessel having a stirrer.
66.5 g, a dispersant 43.1 g, a wetting agent 1.6 g, an antifoaming agent 1.2 g, and titanium oxide 539 g were charged and mixed for 1 hour. The obtained mixed liquid was further dispersed by a nanomill (dispersing machine), and dispersed until the particle diameter of titanium oxide became 10 μm or less. This dispersion was charged into a mixing vessel, and 2087 g of an acrylic silicone resin emulsion and 5.57 g of an antifoaming agent were added thereto. Further, 146.1 g of a film-forming aid, 73.7 g of a drying regulator, and 20. 9 g of a thickener was added and mixed until uniform to prepare a white paint (A) (viscosity: 3000 mPa · s · 25 ° C., heating residue: 45%, density: 1.24).

For 100 parts by weight of this white paint (A)
Aqueous colloidal silica (silica solids)
10 parts by weight) and a dissolver (mixed
(Mixer) to obtain an aqueous inorganic coating composition. Profit
The water-based inorganic coating composition is subjected to a primer treatment.
0.2 kg / m on a 150 x 70 x 4 mm slate plate
^TwoAnd applied for 14 days at room temperature
Was used as a specimen in each test.

<Examples 2 to 13> An aqueous inorganic coating composition and a test specimen were prepared in the same manner as in Example 1 except that the compositions of the white paint (A) and the matting agent were changed as shown in Table 1.

Example 14 In a mixing container having a stirrer, 370 g of water, 4 g of a pH adjuster, 2 g of a thickener, 86 g of a dispersing / wetting agent, 16 g of an anti-algae / anti-mold agent, 4.5 g of an antifoaming agent, 4.5 g of titanium oxide 1000 g was charged and mixed for 1 hour. The obtained mixed liquid was further dispersed by a nanomill, and dispersed until the particle diameter of titanium oxide became 10 μm or less. This dispersion is charged into a mixing vessel, into which 3,000 g of a room temperature-curable acrylic resin emulsion, 10 g of a defoamer, 50 g of a drying regulator, 325 g of a film-forming aid, 135 g of water, and a thickener 2
Add 1 g and mix until uniform, white paint (B)
Was prepared (paint viscosity: 5500 mPa · s · 25 ° C.,
Heating residue: 51%, density: 1.20).

With respect to 100 parts by weight of this white paint (B)
Aqueous colloidal silica (silica solid content: 40 weight
%) 20 parts by weight and potassium titanate whisker 2% by weight
And the viscosity was adjusted to obtain an aqueous inorganic coating composition.
The obtained aqueous inorganic coating composition was subjected to a primer treatment.
0.2kg / on a 150x70x4mm slate
m ^TwoAfter applying, cure at room temperature for 14 days.
Thus, the test specimens in each test were used.

Example 15 In a mixing vessel having a stirrer, 400 g of water, 4 g of a pH adjuster, 2.1 g of a thickener, 36 g of a dispersing / wetting agent, 8 g of a fungicide, 4.5 g of a defoamer, and 1000 g of titanium oxide And mixed for 1 hour. The obtained mixed liquid was further dispersed by a nanomill, and dispersed until the particle diameter of titanium oxide became 10 μm or less. This dispersion is charged into a mixing container, into which 3000 g of an emulsion resin in which styrene and an acrylic monomer are copolymerized, 5.4 g of an antifoaming agent, 50 g of a drying regulator, 360 g of a film-forming auxiliary, 360 g of water
10 g and 60 g of a thickener were added and mixed until uniform to prepare a white paint (C) (paint viscosity: 5500).
mPa · s · 25 ° C., heating residue: 52%, density: 1.1
5).

For 100 parts by weight of this white paint (C)
Aqueous colloidal silica (silica solid content: 40 weight
%) 20 parts by weight and potassium titanate whisker 2% by weight
And the viscosity was adjusted to obtain an aqueous inorganic coating composition.
The obtained aqueous inorganic coating composition was subjected to a primer treatment.
0.2kg / on a 150x70x4mm slate
m ^TwoAfter applying, cure at room temperature for 14 days.
Thus, the test specimens in each test were used.

<Evaluation of Specimens> The specimens obtained in Examples 1 to 15 were evaluated as follows, and the results are shown in Table 1.

(Accelerated Weathering Test) Using an I-Super UV tester SUV-W151 manufactured by Iwasaki Electric Co., Ltd., a test cycle (one cycle) in which the specimen was irradiated with ultraviolet rays for 4 hours and then subjected to condensation for 4 hours. ; 8 hours), 5
Repeated 0 times (400 hours total). The conditions at the time of ultraviolet irradiation are: ultraviolet wavelength: 295 to 450 nm, humidity: 50%, ultraviolet illuminance: 100 mW / cm ² , irradiation temperature: 63 ° C., and humidity of 100% during dew condensation.
The conditions were such that the temperature in the bath gradually decreased from 60 ° C to 20 ° C. Furthermore, at the beginning and the end of the dew condensation, pure water was sprayed on the specimen for 15 seconds.
After completion of the accelerated exposure test, the surface of the test specimen was visually observed, and the appearance change (yellowing, swelling) and occurrence of cracks of the test specimen were evaluated according to the following three grades.

[Appearance change] ：: No change ：: Slight yellowing observed X: Yellowing and swelling observed [Crack generation] ：: None ：: Small cracks occurred in part of test specimen ×: Cracks occur on the entire surface of the specimen

(Outdoor Exposure Test) The test specimen was fixed on a weather test stand inclined at 30 ° to the south side, and the change in whiteness (dirt) on the surface of the test specimen after 6 months was observed. The whiteness of the unwashed specimen after the outdoor exposure test was measured using a color difference meter (Nippon Denshoku Industries Co., Ltd.), and the stain resistance of the coating film was determined as a difference ΔL * from the initial whiteness of the specimen. Was. Note that Δ
The larger the negative value of L *, the darker the coating film after the outdoor exposure test, indicating that the coating is more contaminated.

(Adhesion Test) The adhesion of the coating film was evaluated in accordance with the grid test method of JIS K5400 8.5.2. Specifically, the cellophane tape is adhered to the coating with the grid-like cut, and the coated film is peeled instantaneously in a direction perpendicular to the painted surface with one end of the adhered cellophane tape. Deficiency status was evaluated. The adhesion state between the white paint film and the primer was determined to be 0 points (defect area: 65% or more of the entire square area), 2 points (defect area: 35 to 65% of the entire square area), 4 points (defect area) : 15 to 35% of the entire square area), 6 points (defect area: 5 to 15% of the entire square area), 8 points (defect area: 5 of the entire square area)
% Or less) and 10 points (no defect), and the test results were evaluated in three stages. ○: 8, 10 points △: 4, 6 points ×: 0, 2 points

(Repeated test of heating and cooling) JIS K5400
9.4. Specifically, the test specimen was immersed in water at 20 ° C. for 18 hours, and then heated in a −20 ° C. freezer for 3 hours and further at 50 ° C. for 3 hours. This cycle was repeated for 40 cycles. After completion of the test, the state of the coating film was visually observed, and the crack resistance of the coating film was evaluated on the following three levels. ：: no change △: small cracks and swelling are observed ×: remarkable cracks and peeling are observed

(Flame Retardancy Test) The tip of the flame from the gas burner was brought close to the test specimen inclined at 45 ° to the extent of contact with the painted surface, and heating was continued for 3 minutes. The state of the test specimen during heating was observed, and the flame retardancy of the coating film was evaluated on the following three levels. ：: No change △: Partial carbonization is observed ×: Burns out with flame, or resin components decompose and volatilize

[0050]

[Table 1]

As is clear from the results in Table 1, an acrylic resin (paint (B), Example 1) was used as a resin component of the paint composition.
4) and acrylic styrene resin (paint (C), Example 15)
It can be seen that in the case of using, there is a problem in the flame retardancy of the obtained coating film. In these cases, it can also be seen that the appearance of the coating film is liable to deteriorate. On the other hand, when the acrylic silicone resin of the present invention was used, a coating film having excellent flame retardancy was obtained (Examples 1 to 12).

Also, when polyethylene wax dispersion was blended as a matting agent with acrylic silicone resin (Example 13), sufficient flame retardancy was not obtained,
It also shows that the coating film is liable to crack.

Further, from the results shown in Table 1, in the water-based coating composition of the present invention, the amount of the matting agent (solid content ratio) with respect to the amount of the resin component was set to a specific range (Examples 1 to 5).
9) It can be understood that a matte coating film having excellent crack resistance in addition to flame retardancy can be obtained. Further, in such a case, it can be seen that the weather resistance, stain resistance and adhesion of the coating film are also improved.

[0054]

As described above, in the aqueous inorganic coating composition of the present invention, an acrylic silicone resin emulsion is used as a resin component, and aqueous colloidal silica and / or potassium titanate whisker is further blended as a matting agent. Thus, it is possible to improve the flame retardancy and the like which were not sufficient in the conventional water-based paint composition for a matte coating film. In particular, by setting the amount of the matting agent to the acrylic silicone resin in a specific range, it is possible to obtain a matte coating film having excellent flame resistance and crack resistance. Further, when the amount of the matting agent with respect to the acrylic silicone resin is in a specific range, the weather resistance, stain resistance and adhesion of the obtained coating film can be improved.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor, Kiko Sone 29-47, Marugasaki-cho, Saitama, Saitama Prefecture (72) Inventor, Hiroyuki Kato 1369-1, Minoda, Konosu, Saitama F-term (reference) 4J038 CG001 CL001 MA08 MA10 MA10 NA15

Claims (1)

[Claims] 1. An aqueous inorganic coating composition comprising an acrylic silicone resin emulsion and at least one compound selected from the group consisting of aqueous colloidal silica and potassium titanate whiskers.