JPH08199083A - Pigment dispersion composition and coating composition - Google Patents

Abstract

(57) [Summary] [Object] To make it possible to stably disperse a metal oxide pigment over a long period of time and to obtain good redispersibility. [Structure] The general formula is R ¹ _n SiX _4-n (wherein, R ¹ represents the same or different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and n is an integer of 0 to 3). , X represents a hydrolyzable group) is partially hydrolyzed in colloidal silica dispersed in an organic solvent or water to give a silica-dispersed oligomer solution of organosilane and an organic solvent. To obtain an organosilane solution consisting of
To this, at least one of a metal oxide pigment, fine powder silica and fine powder alumina, and at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide are added.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention coats the surface of a steel plate such as stainless steel, a non-ferrous metal base such as aluminum, a ceramic base such as concrete, slate, or mortar, or a glass base or a plastic base. The present invention relates to a pigment dispersion composition and a coating composition used for forming a coating film having excellent weather resistance, chemical resistance, heat resistance and stain resistance.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of maintenance-free coating materials, the demand for super durable coating films has been strongly demanded for coating materials for outdoor coating. Therefore, it has high hardness, weather resistance, chemical resistance, and heat resistance on the surface of metal base materials such as iron, stainless steel and aluminum, ceramic base materials such as concrete, slate and mortar, glass base materials and plastic base materials. As a coating material for forming a coating film having excellent properties and stain resistance, organosilane-based paints have been attracting attention.
Various items are provided in, for example, Japanese Patent No. 5388.

Since this organosilane-based coating material forms an inorganic coating film, it has excellent coating film physical properties in terms of durability and the like as compared with organic coating materials, but when it is used as a colored coating material, it is a pigment. Difficulty in dispersion and pigment dispersion stability.

[0004]

For example, a coating composition in which a pigment is dispersed in a vehicle composed of a partial condensate of silanol and colloidal silica has been proposed. However, the pot life of the coating is short and there are practical problems. Many. As an improvement, a method of combining a specific molecular weight organopolysiloxane with colloidal silica and colloidal alumina and blending a pigment into it, or a method of blending a pigment into a specific molecular weight organopolysiloxane and adding alkoxysilane and colloidal silica , A method of combining colloidal alumina has been proposed. However, in these methods, when the pigment is dispersed in the organopolysiloxane, there is a problem that the polycondensation of the organopolysiloxane further progresses and gelation occurs during storage, and even if the gelling does not proceed, the molecular weight change occurs. There is a problem that the physical properties of the film change.

When an attempt is made to disperse the pigment in the organosilane, the organosilane itself has a low viscosity, so that the pigment agglomerates and precipitates, and the precipitate becomes a hard cake, and the original dispersion is obtained even when stirred. There is a problem of not returning to the body. In order to prevent this, it is considered to add an organic thickener or an anti-settling agent, but this causes deterioration of the physical properties of the coating film.

Among the various pigments, the metal oxide pigments have a large particle size and a large specific gravity, so that they are prone to sedimentation and the above problems are particularly likely to occur. The present invention has been made in view of the above points, and it is possible to stably disperse the metal oxide pigment for a long period of time and to obtain good redispersibility. It is intended.

[0007]

The pigment dispersion composition according to the present invention has a general formula of R ¹ _n SiX _4-n (wherein R ¹ is the same or different and has 1 to 8 substituted or unsubstituted carbon atoms). Is a monovalent hydrocarbon group, n is an integer of 0 to 3, and X is a hydrolyzable group), and the hydrolyzable organosilane is partially dispersed in colloidal silica dispersed in an organic solvent or water. Obtained by hydrolysis, in an organosilane solution consisting of a silica-dispersed oligomer solution of organosilane and an organic solvent, at least one of a metal oxide pigment, fine powder silica and fine powder alumina, aluminum alkoxide and titanium alkoxide. It is characterized in that at least one of zirconium alkoxides is mixed.

In this pigment dispersion composition, 50 parts of the metal oxide pigment is added to 100 parts by weight of the organosilane solution.
˜200 parts by weight, preferably 1 to 20 parts by weight of at least one of fine powder silica and fine powder alumina. Further, with respect to 100 parts by weight of the organosilane solution, at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide is added to 0.1 parts by weight.
It is preferable to add ~ 5 parts by weight.

The coating composition according to the present invention is characterized by comprising the above pigment dispersion composition, at least one of a surfactant and a resin, a catalyst, and a curing agent. In this coating composition, the curing agent has an average composition formula of R ² _a Si (OH) _b O _{(4 -ab) / 2} (wherein R ² is the same or different and has a substituted or unsubstituted carbon number). 1 to 8
Represents a valent hydrocarbon group, and a and b are each 0.2 ≦ a
<2.0, 0.0001 ≦ b ≦ 3, and a + b <4, which is a number satisfying the relationship), and a polyorganosiloxane containing a silanol group in the molecule is preferable.

Further, it is preferable to use a resin selected from cellulose resins, acrylic silicone resins, silicone resins and fluorine resins. Further, a surfactant is added to 0.0 per 100 parts by weight of the pigment dispersion composition.
It is preferable to add 5 to 5 parts by weight. Furthermore, it is preferable to add 0.05 to 20 parts by weight of resin to 100 parts by weight of the pigment dispersion composition.

The present invention will be described in detail below. The organosilane solution used in the present invention has the general formula R ¹ _n SiX _4-n (1) (wherein R ¹ is the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms). , N is an integer of 0 to 3, and X is a hydrolyzable group), and the hydrolyzable organosilane represented by the formula (1) is dispersed in an organic solvent or water (including a mixed solvent of an organic solvent and water). 1 for colloidal silica
One or two or more kinds, which are obtained by partially hydrolyzing the hydrolyzable organosilane with water in colloidal silica or water added separately, and comprising a silica-dispersed oligomer solution of organosilane and an organic solvent. Is.

Here, the group R ¹ in the hydrolyzable organosilane represented by the above general formula (1) represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, such as methyl. Alkyl groups such as groups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups, heptyl groups, octyl groups;
Cycloalkyl groups such as cyclopentyl group and cyclohexyl group; aralkyl groups such as 2-phenylethyl group, 2-phenylpropyl group and 3-phenylpropyl group; aryl groups such as phenyl group and tolyl group; vinyl group, allyl group, etc. Alkenyl group; halogen-substituted hydrocarbon group such as chloromethyl group, γ-chloropropyl group, 3,3,3-trifluoropropyl group; and γ-methacryloxypropyl group, γ-glycidoxypropyl group, 3,4 Examples thereof include substituted hydrocarbon groups such as an epoxy cyclohexylethyl group and a γ-mercaptopropyl group. Among these, an alkyl group having 1 to 4 carbon atoms and a phenyl group are preferred because of their ease of synthesis or availability.

The hydrolyzable group X in the hydrolyzable organosilane represented by the above general formula (1) includes an alkoxy group, an acetoxy group, an oxime group, an enoxy group, an amino group, an aminoxy group and an amide group. Is mentioned. An alkoxy group is preferable because it is easily available and a fine particle oxide-dispersed oligomer solution is easily prepared. And as such a hydrolyzable organosilane, mono-, di-, tri-, and tetra-functional alkoxysilanes in which n in the general formula (1) is an integer of 0 to 3, Examples thereof include acetoxysilanes, oxime silanes, enoxysilanes, aminosilanes, aminoxysilanes, and amidosilanes. Alkoxysilanes are preferred because they are easily available and a silica-dispersed organosilane oligomer solution is easily prepared.

Particularly, as tetraalkoxysilane with n = 0, tetramethoxysilane, tetraethoxysilane and the like can be exemplified, and as organotrialkoxysilane with n = 1, methyltrimethoxysilane and methyltriethoxysilane. , Methyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, and the like. N = 2
Examples of the diorganodialkoxysilane may include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, and the like. As the triorganoalkoxysilane of n = 3,
Examples thereof include trimethylmethoxysilane, trimethylethoxysilane, trimethylisopropoxysilane, and dimethylisobutylmethoxysilane. still,
An organosilane compound generally called a silane coupling agent can also be used as the alkoxysilanes.

Among the hydrolyzable organosilanes represented by the general formula (1), 50 mol% or more is n = 1.
It is preferably trifunctional. It is more preferably 60 mol% or more, and most preferably 70 mol% or more. If the trifunctional n = 1 is less than 50 mol%, it may be difficult to obtain sufficient coating hardness and the dry curability may be deteriorated.

As the colloidal silica in the organosilane solution, water-dispersible or non-aqueous organic solvent-dispersed colloidal silica such as alcohol can be used. Such colloidal silica generally has a solid content of 20 to 50.
It contains silica by weight, and the amount of silica can be determined from this value. When using the water-dispersible colloidal silica, water other than the solid content can be used for the hydrolysis of the hydrolyzable organosilane. As such colloidal silica, a commercial product can be easily obtained and used.

The organic solvent-dispersed colloidal silica can be easily prepared by substituting water for the water-dispersible colloidal silica with an organic solvent. As with the water-dispersible colloidal silica, commercial products can be easily obtained and used for such organic solvent-dispersed colloidal silica. The type of organic solvent that disperses the colloidal silica is
For example, methanol, ethanol, isopropanol,
Lower aliphatic alcohols such as isobutanol; ethylene glycol, ethylene glycol monobutyl ether,
Examples thereof include ethylene glycol derivatives such as ethylene glycol monoethyl ether acetate; diethylene glycol derivatives such as diethylene glycol and diethylene glycol monobutyl ether; and diacetone alcohol. One or more selected from the group consisting of these can be used, but in combination with these hydrophilic organic solvents, toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, Methyl ethyl ketoxime and the like can also be used.

In the organosilane solution, colloidal silica is preferably added so as to be contained in the range of 5 to 95% by weight as a silica content, more preferably 10 to 90% by weight, and most preferably 20 to 85% by weight. It is in the range of% by weight. If the content is less than 5% by weight, it is difficult to obtain the desired coating hardness, and if it exceeds 95% by weight, it is difficult to uniformly disperse the silica, which may lead to problems such as gelation of the organosilane.

The organosilane solution is usually prepared as a solution comprising a silica-dispersed oligomer of organosilane obtained by partial hydrolysis of hydrolyzable organosilane in water-dispersed colloidal silica or organic solvent-dispersed colloidal silica and an organic solvent. can do.
The amount of water used with respect to the hydrolyzable organosilane is preferably 0.001 to 0.5 mol of water with respect to 1 mol of the hydrolyzable group X. If the amount of water used is less than 0.001 mol, a sufficient partial hydrolyzate cannot be obtained, and if the amount of water used exceeds 0.5 mol, the stability of the partial hydrolyzate may deteriorate. There is. The method of partial hydrolysis is not particularly limited, it is sufficient to mix the hydrolyzable organosilane and colloidal silica, and add the required amount of water, at which time the partial hydrolysis reaction proceeds at room temperature,
You may make it heat at the temperature of 60-100 degreeC in order to accelerate | stimulate a partial hydrolysis reaction. For the purpose of further promoting the partial hydrolysis reaction, hydrochloric acid, acetic acid, halogenated silane, chloroacetic acid, citric acid, benzoic acid, dimethylmalonic acid, formic acid, propionic acid, glutaric acid, glycolic acid,
An inorganic or organic acid such as maleic acid, malonic acid, toluenesulfonic acid or oxalic acid may be used as a catalyst.

The organic solvent in the organosilane solution is
When an organic solvent-dispersed colloidal silica is used, it is introduced from this organic solvent-dispersed colloidal silica, but in addition to this, it can also be introduced as an organic solvent added to adjust the solid content. The type of this organic solvent in the organosilane solution, when introduced from an organic solvent-dispersed colloidal silica, is the one already mentioned as an organic solvent for dispersing colloidal silica, and is introduced as an organic solvent for solid content adjustment. In this case, it is one or more selected from toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methyl ethyl ketoxime and the like. The organic solvent for adjusting the solid content is preferably added when the hydrolysis of the organosilane is completed.

The organosilane solution has a pH in the range of 2.0 to 7.0, more preferably in the range of 2.5 to 6.5, and even more preferably in order to obtain long-term stable performance. Is preferably adjusted to a pH range of 3.0 to 6.0. If the pH is out of this range, the long-term performance deterioration of the organosilane solution may become remarkable especially when the amount of water used is 0.3 mol or more per 1 mol of X. pH
When is out of this range, pH may be adjusted by adding a basic reagent such as ammonia or ethylenediamine if it is acidic side than this range, and if it is basic side than this range, hydrochloric acid, nitric acid, acetic acid. The pH may be adjusted using an acidic reagent such as. Of course, this adjusting method is not particularly limited.

On the other hand, considering that it is an ultra-durable paint, it is necessary to use a durable pigment. In the present invention, a metal oxide pigment is used as a pigment satisfying such requirements. Examples of the metal oxide pigments include titanium oxide, red iron oxide, yellow iron oxide, black iron oxide, ferrite, carbon black, chromium oxide, aluminum oxide, aluminum hydroxide, zirconium oxide, manganese oxide, cobalt oxide, and dioxide. Silicon, barium sulfate, barium carbonate, calcium carbonate, magnesium carbonate, titanium yellow, mica, cobalt green, titanium cobalt green, cobalt blue, cobalt aluminum chrome blue, cobalt chrome green, cerulean blue, cobalt zinc silica blue, zinc oxide, copper Examples thereof include chrome black, copper-iron manganese black, chrome tin pink, chrome alumina pink, vanadium blue, praseodymium yellow, Victoria green, and cobalt silicate. Further, pigments called fine particle pigments, for example, fine particle titanium oxide, fine particle iron oxide, fine particle calcium carbonate, fine particle titanium yellow, fine particle cobalt blue, fine particle cobalt aluminum chrome blue, fine particle copper chrome black and the like can also be mentioned.

These metal oxide pigments are preferably added in the range of 50 to 200 parts by weight with respect to 100 parts by weight of the organosilane solution. When the addition amount is less than 50 parts by weight, it is difficult to prevent the precipitation of the metal oxide pigment and it is economically unfavorable, and when it exceeds 200 parts by weight, the dispersion of the metal oxide pigment becomes difficult, which is preferable. Absent.

In the present invention, at least one of fine powder silica and fine powder alumina is added. As the fine powder silica, either hydrophilic silica or hydrophobic silica can be used. Commercially available products are "AEROSIL 20", "380" and "3" manufactured by Nippon Aerosil Co., Ltd.
80PE ", Degussa's" R972 "," OK52 "
0 "," TS100 "," OK607 "," TS720 "manufactured by Cabosil Co., Ltd., and" Nips "manufactured by Nippon Silica Industry Co., Ltd.
il E200 ”,“ E200A ”,“ E22 ”
0 ”,“ E220A ”,“ ND ”,“ LAPONIT
EXXL "and the like can be exemplified. Further, as the fine powder alumina, for example, "aluminum oxide C" manufactured by Degussa of Germany can be exemplified.

The organosilane solution has almost no viscosity, but the viscosity of the system can be increased by adding these fine powder silica and fine powder alumina. The addition amount of fine powder silica or fine powder alumina is preferably in the range of 1 to 20 parts by weight with respect to 100 parts by weight of the organosilane solution. If the addition amount is less than 1 part by weight, the effect of adding fine powder silica or fine powder alumina cannot be expected, and if the addition amount exceeds 20 parts by weight, the gloss of the coating film decreases. It is not preferable because it becomes noticeable. By increasing the viscosity of the system by adding fine powder silica or fine powder alumina in this way, it is possible to increase the dispersion stability of the metal oxide pigment, but by adding fine powder silica or fine powder alumina, It is difficult to prevent sedimentation of a metal oxide pigment having a large specific gravity and a large particle diameter for a long period of time and to stabilize it. Rather, the addition of fine powder silica or fine powder alumina contributes to the effect of improving redispersibility after storage by interposing fine powder silica or fine powder alumina between particles of the metal oxide pigment. Can be considered. By coexisting with the metal alkoxide described below, the effect of improving rheological properties is exhibited, and a pigment dispersion composition having both long-term stability and redispersibility can be obtained.

The metal alkoxide is a compound represented by the general formula of M (OR) n having the property of reacting with water and hydrolyzing, and OR = methoxy group, ethoxy group, M = Al, Ti, Zi, etc. Examples of the isopropoxy group, butoxy group and the like include aluminum alkoxide, titanium alkoxide and zirconium alkoxide in the present invention.
Aluminum alkoxide, titanium alkoxide,
One kind of zirconium alkoxide may be used, or two or more kinds thereof may be mixed and used, but from the viewpoint of viscosity, it is most preferable to use aluminum alkoxide.

The system can be thickened by adding these metal alkoxides. The metal alkoxide is hydrolyzed or partially hydrolyzed by the water adsorbed on the metal oxide-based pigment or the water contained in the organosiloxane solution in a trace amount, and structural viscosity is generated in the dispersion liquid. It is considered that the viscosity increases, but the dispersion containing the metal alkoxide exhibits very thixotropic properties. Therefore, the addition of these metal alkoxides has no effect on the dispersion of the metal oxide pigment in the dispersion step. The metal alkoxide is effective even if added in a small amount, and even when a metal oxide pigment having a large specific gravity is dispersed in a vehicle having no viscosity such as the organosilane solution used in the present invention, the pigment is prevented from settling for a long time. Exerts a surprising effect. Further, by using it in combination with the above-mentioned fine powder silica or fine powder alumina, viscosity adjustment and redispersibility can be provided. What is more effective is that the metal alkoxide consumes the water contained in the organosilane solution that becomes the pigment or vehicle, and the effect of the water on the vehicle, that is, the condensation polymerization of the organosilane is promoted and the molecular weight is changed. It is possible to suppress changes in the physical properties of the film and contribute to the stability of the vehicle itself.

In order to effectively obtain such effects, the amount of the above metal alkoxide added is preferably in the range of 0.1 to 5 parts by weight, more preferably 0, based on 100 parts by weight of the organosilane solution. It is in the range of 3 to 3 parts by weight.
If the addition amount is less than 0.1 parts by weight, it is difficult to obtain a stable dispersion liquid, and if the addition amount is more than 5 parts by weight, the viscosity of the dispersion liquid becomes too high, which may make the handling difficult.

The pigment dispersion composition obtained as described above is capable of stably dispersing a metal oxide pigment at a high concentration for a long period of time and is excellent in redispersibility. By using this pigment dispersion composition, it is possible to prepare a coating composition having excellent pigment dispersion stability and redispersibility. Moreover, since this pigment dispersion composition uses an organosilane solution as a vehicle, it can be used without adversely affecting physical properties such as hardness, chemical resistance, weather resistance, heat resistance and stain resistance of the final coating film. Is what you can do. In addition, in order to adjust the pigment concentration of the pigment dispersion composition prepared as described above, it is necessary to add the organosilane solution described above or the same organosilane solution except that it does not contain colloidal silica. You can

Next, a coating composition using the above pigment dispersion composition will be described. The coating composition is generally prepared by blending a main agent, a curing agent, a catalyst that accelerates the reaction between the main agent and the curing agent, and a pigment, but in the present invention, the pigment is not directly blended, but the above By using the pigment dispersion composition in which the pigment is previously dispersed as the main component as described above, a coating composition in which the pigment is stably dispersed can be obtained.

Here, in the present invention, the curing component in the curing agent has an average composition formula of R ² _a Si (OH) _b O _{(4-ab) / 2} (2) (wherein R ² is the same. Or a different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and a and b are 0.2 ≦ a <2.0, 0.0001 ≦ b ≦ 3, a +, respectively.
A polyorganosiloxane having a silanol group in the molecule, represented by a number satisfying the relationship of b <4) is used.

In the formula (2), R ² is the above formula (1).
The same as R ^{1 in the above} can be exemplified, but preferably an alkyl group having 1 to 4 carbon atoms, a phenyl group, a vinyl group, a γ-glycidoxypropyl group, a γ-methacryloxypropyl group, 3,3 And a substituted hydrocarbon group such as a 3-trifluoropropyl group, and more preferably a methyl group and a phenyl group. In the formula (3), a and b are 0.2 ≦ a <2.0, 0.0001 ≦ b ≦ 3, and a +, respectively.
It is a number that satisfies the relationship of b <4, and a is less than 0.2 or b
When the value exceeds 3, there is an inconvenience such as the occurrence of cracks in the cured film, and when a exceeds 2.0 and 4 or less, or b
Is less than 0.0001, there is a disadvantage that curing does not proceed well.

The silanol group-containing polyorganosiloxane of the formula (2) is, for example, one or two of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or an alkoxysilane corresponding thereto. It can be obtained by hydrolyzing the above mixture with a large amount of water by a known method. When the silanol group-containing polyorganosiloxane is hydrolyzed by a known method using an alkoxysilane, a small amount of unhydrolyzed alkoxy groups may remain. That is, a polyorganosiloxane in which a silanol group and a trace amount of an alkoxy group coexist may be obtained, but such a polyorganosiloxane may be used.

In the present invention, the catalyst is an essential component for accelerating the condensation reaction between the silica-dispersed oligomer of organosilane in the pigment dispersion composition as the main component and the curing agent to cure the coating film. Examples of the catalyst include metal salts of carboxylic acids such as alkyl titanates, tin octylate and dibutyltin dilaurate, dioctyltin dimaleate; amine salts such as dibutylamine-2-hexoate, dimethylamine acetate, ethanolamine acetate; tetramethyl acetate. Ammonium and other carboxylic acid quaternary ammonium salts, tetraethylpentamine and other amines; N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane, ethylenediaminemethylpropyldimethoxysilane and other amine silane coupling agents; p
-Acids such as toluenesulfonic acid, phthalic acid, hydrochloric acid; aluminum compounds such as aluminum alkoxide and aluminum chelate; alkali catalysts such as potassium hydroxide;
There are titanium compounds such as tetraisopropyl titanate, tetrabutyl titanate and titanium tetraacetylacetonate, halogenated silanes such as methyltrichlorosilane, dimethyldichlorosilane and trimethylmonochlorosilane, and other silica-dispersed oligomers of organosilane. There is no particular limitation as long as it is effective for the condensation reaction of the curing agent with the curing agent.

The mixing ratio of the pigment dispersion composition and the curing agent and the amount of the catalyst can be arbitrarily set according to the required coating film performance and curability, but the organosilane component in the pigment dispersion composition. It is preferable to adjust the content of the polyorganosiloxane component in the curing agent in the range of 99 to 1 part by weight based on 1 to 99 parts by weight, and more preferably, the polyorganosiloxane based on 5 to 95 parts by weight of the organosilane component. The component is in the range of 95 to 5 parts by weight, most preferably 10 to 90 parts by weight of the organosilane component and 90 to 10 parts by weight of the polyorganosiloxane component (however, the total amount of the organosilane component and the polyorganosiloxane component is 10
0 parts by weight).

Further, in the present invention, in order to secure color stability, at least one of a surfactant and a resin is added as an additive to the main component. Examples of such a surfactant include a carboxylic acid-based surfactant, a polymer copolymer-based surfactant, an amine-based surfactant, an ester-based surfactant, and the like, and a surfactant particularly suitable for the present invention As the above, a carboxylic acid type surfactant, a high molecular weight copolymer type surfactant and an amine type surfactant are preferable. As the commercially available product, "Byk-P10" manufactured by Byk-Chemie is available.
4 ”,“ P104S ”,“ 240S ”,“ Disper ”
byk-160 "," Disperbyk-161 ",
"Disperbyk-162", "Disperby
k-163 "," Disperbyk-164 "," D
isperbyk-165 "," Disperbyk-
166 ”,“ Anti-Terra-203 ”,“ Di ”
“Sperbyk”, “Disperbyk-181” and the like. It is difficult to ensure color stability with other surfactants. The amount of the surfactant added is the same as that of the pigment dispersion composition 1
0.05 to 5 parts by weight, preferably 0.05 to 1.6 parts by weight, most preferably 1.1 to 1.
6 parts by weight. If the amount of the surfactant added is less than 0.05 parts by weight, the effect of preventing color separation will be insufficient, and if it exceeds 5 parts by weight, the pigments will excessively aggregate and a smooth coating film cannot be obtained. At the same time, the stability of the paint during long-term storage may deteriorate.

As the resin, many resins such as cellulose resin, acrylic silicone resin, silicone resin, fluorine resin, acrylic resin, urethane resin can be used. Is preferably a cellulose resin, an acrylic silicone resin, a silicone resin, or a fluorine resin. For example, commercially available products of cellulosic resins include "Etocel STD-45" and "Etocel STD-100" manufactured by Dow Chemical Co., Ltd., and commercially available products of acrylic silicone resins include "LY" manufactured by Dainippon Ink and Chemicals, Inc. -805 "," VY-108 ",
"VY-109" and the like are commercially available silicone resins, "TSR116" and "TSR116" manufactured by Toshiba Silicone Co., Ltd.
117 "and the like are commercially available fluororesins such as“ VE471 ”manufactured by Daikin Industries, Ltd. and“ LF-20 ”manufactured by Asahi Glass Co., Ltd.
0 "," N-75 "manufactured by Sumitomo Chemical Co., Ltd., and the like. Other resins may not be well compatible with each other in the pigment dispersion composition, or the pigment precipitation preventing effect may not be sufficiently obtained. The amount of the resin added is 0.05 to 20 parts by weight, preferably 0.55 parts by weight, based on 100 parts by weight of the pigment dispersion composition.
10 to 10 parts by weight, most preferably 0.55 to 7 parts by weight. If the amount of the resin added is less than 0.05 parts by weight, the effect of preventing the sedimentation of the pigment will be insufficient, while if it exceeds 20 parts by weight, the paint may excessively thicken and the smoothness of the coating film may be lost. .

Thus, the coating composition according to the present invention can be applied to steel plates such as stainless steel, non-ferrous metal bases such as aluminum, ceramic bases such as concrete, slate and mortar, or glass bases and plastic bases. By coating the surface, a coating film having excellent weather resistance, chemical resistance, heat resistance, and stain resistance can be formed. The coating can be performed by a coating method, and for example, various coating methods such as brush coating, spraying, dipping, flow, roll, curtain and knife coating can be selected.

[0039]

EXAMPLES The present invention will be further described with reference to examples. Unless otherwise specified, all “parts” are “parts by weight”.
"%" Means "% by weight". Needless to say, the present invention is not limited to these examples. (Example 1) Methyl trimethoxysilane (manufactured by Toshiba Silicone Co., Ltd.) (34.09 parts) in methanol was dispersed in colloidal silica sol (manufactured by Nissan Chemical Industries, Ltd. "MA-ST") 47.62.
An organosilane solution was prepared by hydrolyzing by adding 0.40 parts of water in parts. Then, with respect to 100 parts by weight of this organosilane, 119 parts of titanium oxide as a metal oxide pigment, 2.5 parts of finely powdered silica ("AEROSIL380PE" manufactured by Nippon Aerosil Co., Ltd.), and 0.5 part of aluminum isopropoxide as an aluminum alkoxide. Was mixed, and the pigment was dispersed with a Dynomill so that the dispersity was 10 μm or less to obtain a pigment dispersion composition liquid.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that the pigment dispersion stability was good without formation of a hard cake. The redispersibility of the pigment was also good. (Example 2) To 100 parts of the same organosilane solution as prepared in Example 1, 120 parts of red iron oxide as a metal oxide pigment, "AEROSIL3" manufactured by Nippon Aerosil Co., Ltd.
80PE "1.5 parts, aluminum isopropoxide 1
Parts were mixed and a pigment dispersion composition liquid was obtained in the same manner as in Example 1.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good. Example 3 A pigment dispersion composition liquid was obtained in the same manner as in Example 2 except that black iron oxide was used as the metal oxide pigment instead of red iron oxide.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good. (Example 4) A pigment dispersion composition liquid was obtained in the same manner as in Example 2 except that titanium yellow was used instead of red iron oxide as the metal oxide pigment.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good. (Example 5) A pigment dispersion composition liquid was obtained in the same manner as in Example 2 except that titanium cobalt blue was used instead of red iron oxide as the metal oxide pigment.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that the pigment dispersion stability was good without formation of a hard cake. The redispersibility of the pigment was also good. (Example 6) A pigment dispersion composition liquid was obtained in the same manner as in Example 2 except that cobalt blue was used instead of red iron oxide as the metal oxide pigment.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good. (Example 7) For 100 parts of the same organosilane solution as prepared in Example 1, 119 parts of titanium oxide as a metal oxide pigment, "AEROSIL3" manufactured by Nippon Aerosil Co., Ltd.
80 PE "2.5 parts, aluminum isopropoxide 0.5 part, and titanium tetrabutoxide 0.5 part as titanium alkoxide were mixed, and a pigment dispersion composition liquid was obtained in the same manner as in Example 1.

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good. (Example 8) "AEROSIL38" manufactured by Nippon Aerosil Co., Ltd.
A pigment dispersion composition liquid was obtained in the same manner as in Example 2 except that 1.2 parts of "aluminum oxide C" manufactured by Degussa Co., Ltd. was used as the fine powder alumina instead of "0PE".

Observation of the state of this pigment dispersion composition liquid after standing for 6 months revealed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good. Comparative Example 1 A pigment dispersion composition liquid was obtained in the same manner as in Example 2 except that aluminum isopropoxide was not added.

In this pigment dispersion composition liquid, the sedimentation of the pigment was rapid, and a phenomenon of hard cake formation was observed after several days. (Example 9) White pigment dispersion composition 90 obtained in Example 1
Parts and 10 parts of the brown pigment dispersion composition obtained in Example 2 were mixed, and 46.6 parts of the organosilane solution (hereinafter referred to as a red down resin) solution obtained in Example 1 and polycarboxylic acid as a surfactant. Acid-based surfactant (Byk-Chemie
1.6 parts by weight of "BYK-P104" manufactured by the same company) was mixed and sufficiently stirred with a disper, and then 4.07 parts of ethylenediaminemethylpropyldimethoxysilane and 0.81 part of dibutyltin dilaurate were added as a catalyst, and further sufficiently. It was stirred. Thereafter, 23.4 parts of a 14% toluene solution of ethyl cellulose (“Ethocel STD-100” manufactured by Dow Chemical Co.) as a cellulosic resin (“Ethocel STD-
(100 parts, 3.2 parts) was added and sufficiently stirred with a disper to obtain a main agent. Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

On the other hand, methyltriisopropoxysilane 2
Weigh a mixture of 20 parts and 150 parts of toluene, and measure 1%.
Methyltriisopropoxysilane was hydrolyzed by dropping 108 parts of hydrochloric acid aqueous solution into this mixed solution, and a lower layer water / isopropyl alcohol mixed solution containing a small amount of hydrochloric acid separated into two layers was separated. Next, the residual hydrochloric acid in the resin solution of toluene was removed by washing with water, and toluene was further removed under reduced pressure, followed by diluting with isopropyl alcohol to give an average molecular weight of 200 as a curing agent.
A 40% solution of 0 silanol group-containing organopolysiloxane in isopropyl alcohol was obtained.

Next, with respect to 190.88 parts of the main agent,
A coating composition was obtained by mixing 101.8 parts of this curing agent and 57.4 parts of isopropanol (hereinafter IPA) as a diluent solvent. This coating composition had very good color stability. (Example 10) Instead of a polycarboxylic acid type surfactant as a surfactant, an amine type surfactant (Byk-Che) was used.
A main agent was obtained in the same manner as in Example 9 except that "Disperbyk-181" manufactured by Mie was used. Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

Next, with respect to 190.88 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had very good color stability. (Example 11) Instead of a polycarboxylic acid type surfactant as a surfactant, a polymer copolymer type surfactant (Byk-
A main agent was obtained in the same manner as in Example 9 except that "Disperbyk-163" manufactured by Chemie was used. Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

Next, with respect to 190.88 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had very good color stability. (Example 12) As a resin, an acrylic silicone resin (“V” manufactured by Dainippon Ink and Chemicals, Inc. was used instead of the cellulose resin.
Y-108 ") Example 9 except that 17 parts were used.
A main agent was obtained in the same manner as in. Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

Next, with respect to 184.48 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had very good color stability. (Example 13) Instead of a cellulose resin as a resin, a silicone resin ("TSR11" manufactured by Toshiba Silicone Co., Ltd.) was used.
6 ") A main agent was obtained in the same manner as in Example 9 except that 17 parts were used. Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

Next, with respect to 175.68 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had very good color stability. (Example 14) A base resin was obtained in the same manner as in Example 9 except that 0.3 part of a fluororesin ("N-75" manufactured by Sumitomo Chemical Co., Ltd.) was used as the resin instead of the cellulosic resin.
Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

Next, with respect to 168.48 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had very good color stability. (Example 15) Instead of a polycarboxylic acid type surfactant as a surfactant, a polymer copolymer type surfactant (Byk-
Chemie's “Disperbyk-163”) is used, and an acrylic silicone resin (“VY-” manufactured by Dainippon Ink and Chemicals, Inc.) is used instead of the cellulose resin as the resin.
No. 108 ″) 17 parts were used to obtain a base material in the same manner as in Example 9. Pigment sedimentation was extremely unlikely to occur with this main agent, and even if it did occur, redispersibility was very excellent.

Next, with respect to 200.48 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had very good color stability. (Example 16) A base resin was obtained in the same manner as in Example 9 except that the resin (cellulosic resin) was not added. This main agent was more likely to cause pigment precipitation than that of Example 9, but was extremely excellent in redispersibility.

Next, with respect to 167.48 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had excellent color stability. (Example 17) A main agent was obtained in the same manner as in Example 9 except that the surfactant (polycarboxylic acid type surfactant) was not added. This main agent was more likely to cause pigment precipitation than that of Example 9, but was extremely excellent in redispersibility.

Next, with respect to 174.88 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
This coating composition had excellent color stability. (Comparative Example 2) A base resin was obtained in the same manner as in Example 9 except that neither the surfactant nor the resin was added. This main agent had a rapid pigment sedimentation, and the pigment sedimentation layer was liable to form a hard cake and was difficult to redisperse.

Next, with respect to 151.48 parts of this main agent,
101.8 parts of the curing agent obtained in Example 9 and diluting solvent IPA5
A coating composition was obtained by mixing 7.4 parts.
Also in this coating composition, the pigment settled quickly, redispersion was difficult, and color separation occurred after coating. (Comparative Example 3) As a surfactant, a polycarboxylic acid type surfactant ("BYK-P10" manufactured by Byk-Chemie).
4 ”) A main agent was obtained in the same manner as in Example 9 except that 6 parts were blended. Next, with respect to 195.28 parts of this main agent, 101.8 parts of the curing agent obtained in Example 9 and diluent solvent I
A coating composition was obtained by mixing 57.4 parts of PA. Although the sedimentation of the base material was less likely to occur, when the coating composition was applied, the pigment aggregated excessively, resulting in loss of smoothness of the coating film.

Comparative Example 4 As a surfactant, an amine-based surfactant (“Disperb” manufactured by Byk-Chemie) was used.
yk-181 ") 6 parts were blended to obtain a base material in the same manner as in Example 9. Next, this main agent 195.
101.8 parts of the curing agent obtained in Example 9 against 28 parts,
A coating composition was obtained by mixing 57.4 parts of diluting solvent IPA. Although the sedimentation of the base material was less likely to occur, when the coating composition was applied, the pigment aggregated excessively, resulting in loss of smoothness of the coating film.

(Comparative Example 5) Cellulose resin ("Etocel STD-100" manufactured by Dow Chemical Co.) was used as a resin.
The 4% toluene solution is 25 for "ETOCEL STD-100".
A main component was obtained in the same manner as in Example 9 except that the main component was added. Next, with respect to 345.08 parts of this main component, 101.8 parts of the curing agent obtained in Example 9 and IPA5 of the diluting solvent
A coating composition was obtained by mixing 7.4 parts.
Although pigment precipitation of the main agent was extremely unlikely to occur, the viscosity was extremely high and it was difficult to use. Further, the coating composition also has a very high viscosity, so that the leveling property is poor and the smoothness of the coating film is lost.

(Comparative Example 6) The procedure of Example 9 was repeated, except that 25 parts of an acrylic silicone resin ("VY-108" manufactured by Dainippon Ink and Chemicals, Inc.) was used as the resin instead of the cellulose resin. The main ingredient was obtained. Next, the curing agent 10 obtained in Example 9 was added to 200.48 parts of this main agent.
A coating composition was obtained by mixing 1.8 parts and 57.4 parts of the diluting solvent IPA. Although pigment precipitation of the main agent was extremely unlikely to occur, the viscosity was extremely high and it was difficult to use. Further, the coating composition also has a very high viscosity, so that the leveling property is poor and the smoothness of the coating film is lost.

The coating compositions obtained in Examples 9 to 17 and Comparative Examples 2 to 6 were evaluated for their respective properties such as pigment settling prevention property, redispersibility, color stability and coating film smoothness. The results are shown in Table 1.

[0064]

[Table 1]

In Table 1, with respect to the pigment settling preventive property, those which did not settle for two months or more were indicated by "◯", those which settled in one month were indicated by "△", and those which settled in one week were indicated by "x". Regarding the redispersibility, when a sedimentation layer is formed, it is "○" when the sedimentation layer disappears by stirring for 1 to 2 minutes using a stirrer, and "△" when the sedimentation layer disappears within 5 minutes, The presence of a sediment layer even after stirring for 10 minutes was indicated by "x". Regarding the color stability, among those that do not color-separate immediately after coating, Δ
“E” for E ≦ 0.7, ΔE for the main agent after 3 months
“○” for ≦ 0.7, and ΔE ≦ for the main agent after 1 month
The ones with 0.7 were indicated by “△”, and those with color separation immediately after coating were indicated by “x”. Regarding the smoothness, the one in which the coating film surface is uniformly leveled visually is indicated by "O", and the one in which the coating film surface is visually observed is indicated by "X".

[0066]

As described above, the pigment dispersion composition according to the present invention has a general formula of R ¹ _n SiX _4-n (wherein R ¹ is the same or different and has 1 to 8 substituted or unsubstituted carbon atoms). Is a monovalent hydrocarbon group, n is an integer of 0 to 3, and X is a hydrolyzable group), and the hydrolyzable organosilane is partially dispersed in colloidal silica dispersed in an organic solvent or water. Obtained by hydrolysis, in an organosilane solution consisting of an organosilane silica-dispersed oligomer solution and an organic solvent,
Metal oxide pigment, at least one of fine powder silica and fine powder alumina, at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide added, respectively, the action of aluminum alkoxide or titanium alkoxide or zirconium alkoxide Can prevent the sedimentation of the pigment and improve the redispersibility of the pigment by the action of finely powdered silica or finely powdered alumina, and it is possible to use a pigment having a large particle size and a large specific gravity like a metal oxide pigment for a long period of time. It is possible to obtain a good redispersibility with stable dispersion over, and since the main component is organosilane, the hardness of the inorganic coating film, chemical resistance, weather resistance, Without adversely affecting physical properties such as heat resistance and stain resistance One in which it is possible to use.

The coating composition according to the present invention comprises the above-mentioned pigment dispersion composition, at least one of a surfactant and a resin, a catalyst and a curing agent, so that the action of the surfactant or the resin causes It is possible to ensure color stability and high storage stability, and since the pigment is previously dispersed in the pigment dispersion composition, it is possible to disperse the pigment when preparing the coating composition. The process can be omitted and the productivity can be improved.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Shimada 1048, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Meiji Goto, 1048, Kadoma, Kadoma City, Osaka Matsushita Electric Works Co., Ltd. 72) Inventor Akira Nishio 1-3-4, Ukima, Kita-ku, Tokyo Inside the Inorganic Materials Technology Department, Pigment Technology Headquarters, Dainichiseika Kogyo Co., Ltd. (72) Hiromi Terada 1-3-4, Ukima, Kita-ku, Tokyo (72) Inventor Satoshi Isobe 86 Toyoshima, Iwata City, Shizuoka Prefecture Dainichi Seika Co., Ltd.

Claims (8)

[Claims] 1. A general formula R ¹ _n SiX _4-n (In the formula, R ¹
Represents an identical or different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, n is an integer of 0 to 3, and X represents a hydrolyzable group). Was obtained by partial hydrolysis in colloidal silica dispersed in an organic solvent or water, an organosilane solution consisting of a silica-dispersed oligomer solution of organosilane and an organic solvent, a metal oxide pigment, a fine powder silica. And a finely divided alumina, and at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide, respectively. 2. 100 to 100 parts by weight of an organosilane solution, 50 to 200 parts by weight of a metal oxide pigment, and 1 to 20 of at least one of fine powder silica and fine powder alumina.
The pigment dispersion composition according to claim 1, wherein the pigment dispersion composition is added by weight. 3. The method according to claim 1, wherein 0.1 to 5 parts by weight of at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide is added to 100 parts by weight of the organosilane solution. The pigment dispersion composition described. 4. A coating composition comprising the pigment dispersion composition according to any one of claims 1 to 3, at least one of a surfactant and a resin, a catalyst, and a curing agent. 5. The curing agent has an average composition formula of R ² _a Si (O
H) _b O _{(4-ab) / 2} (In the formula, R ² represents the same or different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and a and b are each 0.2 ≦ or less. a <2.0, 0.0
It is a number that satisfies the relationship of 001 ≦ b ≦ 3 and a + b <4)
The coating composition according to claim 4, which is a polyorganosiloxane having a silanol group in the molecule represented by: 6. The coating composition according to claim 4, wherein a resin selected from cellulose resins, acrylic silicone resins, silicone resins, and fluorine resins is used as the resin. 7. The coating composition according to claim 4, wherein 0.05 to 5 parts by weight of a surfactant is added to 100 parts by weight of the pigment dispersion composition. 8. The coating composition according to claim 4, wherein 0.05 to 20 parts by weight of a resin is added to 100 parts by weight of the pigment dispersion composition.