JPH10324838A - Pigment dispersion composition and coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pigment dispersion composition and a coating composition capable of forming a coating film having markedly high cracking resistance while keeping the redispersibility and color stability high. SOLUTION: There is provided a pigment dispersion composition prepared by adding a metal oxide pigment, at least either a finely powdered silica or a finely powdered alumina and at least one of an aluminum alkoxide, a titanium alkoxide and a zirconium alkoxide to an organosilane solution obtained by partially hydrolyzing a hydrolyzable organosilane represented by the formula: R<1> n SiX4-n (R<1> s are the same or different substituted or unsubstituted 1-8 C monovalent hydrocarbon groups; n is an integer of 0-3; and X is a hydrolyzable group) in colloidal silica dispersed in an organic solvent or water and comprising an organosilane silica dispersed oligomer solution and an organic solvent, wherein 5-60 pts.wt. of the metal oxide pigment is replaced by an acicular metal oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for coating a steel plate such as stainless steel, a nonferrous metal base such as aluminum, a ceramic base such as concrete, slate, mortar, a glass base or a plastic base. Weather resistance,
The present invention relates to a pigment dispersion composition and a coating composition used for forming a coating film having excellent chemical resistance, heat resistance, and stain resistance.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of maintenance-free coatings, demands for ultra-durable coatings have been strongly demanded for outdoor coatings. For this reason, high hardness, weather resistance, chemical resistance, and heat resistance are applied to the surfaces of metal base materials such as iron, stainless steel, aluminum, etc., 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 water resistance and stain resistance, an organosilane-based paint has been attracting attention.
Various types are provided in, for example, Japanese Patent No. 5388.

[0003] Since this organosilane-based coating material is an inorganic coating film, it has excellent coating properties in terms of durability and the like as compared with organic coating materials. Difficulty in dispersion and pigment dispersion stability.

[0004]

For example, there has been proposed a paint composition in which a pigment is dispersed in a vehicle comprising a partial condensate of silanol and colloidal silica, but the paint has a short pot life and has a practical problem. Many.

As an improvement, a method of combining an organopolysiloxane having a specific molecular weight with colloidal silica and colloidal alumina, and blending a pigment with the combination, a method of blending a pigment with an organopolysiloxane having a specific molecular weight, and adding alkoxysilane and A method of combining colloidal silica and colloidal alumina has been proposed. However, in these methods, when the pigment is dispersed in the organopolysiloxane, the polycondensation of the organopolysiloxane further proceeds, causing a problem of gelation during storage. Therefore, there is a problem that the physical properties of the film change.

When the pigment is dispersed in the organosilane, the pigment is agglomerated and sedimented due to the low viscosity of the organosilane itself, and the sediment becomes a hard cake. There is a problem of not returning to the body. In order to prevent this, it is conceivable to add an organic thickener or an antisettling agent, but this causes a decrease in the physical properties of the coating film.

[0007] Among the various pigments, metal oxide pigments have a large particle diameter and a large specific gravity, so that they are liable to settle, and the above-mentioned problems are particularly likely to occur.

Accordingly, the general formula is R ¹ _n SiX _4-n (wherein R ¹ is the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and n is 0 to 3) An integer, X
Represents a hydrolyzable group), and a silica-dispersed oligomer solution of an organosilane obtained by partially hydrolyzing a hydrolyzable organosilane represented by the following formula in colloidal silica dispersed in an organic solvent or water: A pigment dispersion composition comprising a metal oxide pigment, at least one of finely divided silica and finely divided alumina, and at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide, respectively, in an organosilane solution consisting of It is possible to disperse the metal oxide-based pigment stably over a long period of time and obtain good redispersibility, and a strong cracking property can be obtained. However, there is a need for a coating film having ultra-durability, that is, a coating film having extremely strong cracking properties, It has been asked to strongly to the fee.

[0009] The present invention has been made in view of the above points, and while maintaining high redispersibility, color stability, and the like,
It is an object of the present invention to provide a pigment dispersion composition and a coating composition that can significantly enhance cracking properties.

[0010]

The pigment dispersion composition according to the present invention has a general formula of R ¹ _n SiX _4-n (where R ¹ is the same or different and is substituted or unsubstituted having 1 to 8 carbon atoms). Wherein n is an integer of 0 to 3 and X is a hydrolyzable group), and a hydrolyzable organosilane represented by the following formula (1) is partially dissolved in colloidal silica dispersed in an organic solvent or water. Obtained by hydrolysis, an organosilane solution comprising an organosilane silica-dispersed oligomer solution and an organic solvent, a metal oxide pigment, at least one of fine powder silica and fine powder alumina, aluminum alkoxide and titanium alkoxide. A pigment dispersion composition obtained by adding at least one of zirconium alkoxides, wherein 5 to 60 parts by weight of the metal oxide pigment is a needle-shaped metal oxide. It is characterized in that it has replaced.

In this pigment dispersion composition, 50 parts by weight of a metal oxide pigment is added to 100 parts by weight of an organosilane solution.
It is preferable to add 1 to 20 parts by weight of at least one of finely divided silica and finely divided alumina, and 5 to 60 parts by weight of the above metal oxide pigment is acicular metal oxide. It has been replaced with a product.

It is preferable that 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.

A coating composition according to the present invention comprises the above-described 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} (where R
² is the same or different and substituted or unsubstituted 1 to 8 carbon atoms
Wherein a and b are each 0.2
≦ a <2.0, 0.0001 ≦ b ≦ 3, a + b <4), and is preferably a polyorganosiloxane containing a silanol group in the molecule.

It is preferable to use a resin selected from the group consisting of a cellulose resin, an acrylic silicone resin, a silicone resin and a fluorine resin.

Further, it is preferable to add 0.05 to 5 parts by weight of a surfactant to 100 parts by weight of the pigment dispersion composition.

Further, it is preferable to add 0.05 to 20 parts by weight of the resin to 100 parts by weight of the pigment dispersion composition.

[0018]

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

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

Here, the group R ¹ in the hydrolyzable organosilane represented by the general formula (1) represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms. 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 groups and allyl group 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 And substituted hydrocarbon groups such as an epoxycyclohexylethyl group and a γ-mercaptopropyl group. Among these, an alkyl group having 1 to 4 carbon atoms and a phenyl group are preferable from the viewpoint of ease of synthesis or availability.

The hydrolyzable group X in the hydrolyzable organosilane represented by the above general formula (1) includes alkoxy, acetoxy, oxime, enoxy, amino, aminoxy, amide and the like. Is mentioned. Alkoxy groups are preferred because of their availability and ease of preparation of the particulate oxide dispersed oligomer solution.

The hydrolyzable organosilane includes mono-, di-, tri-, and tetra-functional groups, wherein n in the general formula (1) is an integer of 0 to 3. Examples thereof include alkoxysilanes, acetoxysilanes, oxime silanes, enoxysilanes, aminosilanes, aminoxysilanes, and amidosilanes. Alkoxysilanes are preferred because they are easily available and easy to prepare a silica-dispersed organosilane oligomer solution.

Particularly, tetraalkoxysilanes with n = 0 include tetramethoxysilane, tetraethoxysilane and the like, and organotrialkoxysilanes with n = 1 include methyltrimethoxysilane and methyltriethoxysilane. , Methyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, and the like. Also, n = 2
Examples of the diorganodialkoxysilane include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and methylphenyldimethoxysilane. Examples of the triorganoalkoxysilane having n = 3 include:
Examples thereof include trimethylmethoxysilane, trimethylethoxysilane, trimethylisopropoxysilane, and dimethylisobutylmethoxysilane. still,
Organosilane compounds generally called silane coupling agents can also be used as alkoxysilanes.

In the hydrolyzable organosilane represented by the general formula (1), at least 50 mol% of n = 1
Preferably, it is a trifunctional compound. It is more preferably at least 60 mol%, most preferably at least 70 mol%. If the trifunctional compound having n = 1 is less than 50 mol%, it is difficult to obtain a sufficient film hardness, and the dry curability may be inferior.

As the colloidal silica in the organosilane solution, water-dispersible or non-aqueous organic solvent dispersible 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 silica content can be determined from this value.

When water-dispersible colloidal silica is used, water other than solid content can be used for hydrolysis of hydrolyzable organosilane. Such colloidal silica can be easily obtained and used as a commercial product.

The organic solvent-dispersed colloidal silica can be easily prepared by replacing the water of the water-dispersible colloidal silica with an organic solvent. As with the water-dispersible colloidal silica, a commercially available product can be easily obtained and used as such an organic solvent-dispersed colloidal silica. The type of organic solvent that disperses colloidal silica is
For example, methanol, ethanol, isopropanol,
Lower aliphatic alcohols such as isobutanol; ethylene glycol, ethylene glycol monobutyl ether,
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 can also be used.

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

The organosilane solution is usually prepared as a solution comprising an organosilane silica-dispersed oligomer and an organic solvent obtained by partially hydrolyzing a hydrolyzable organosilane in water-dispersed colloidal silica or colloidal silica dispersed in an organic solvent. can do.
The amount of water used relative to the hydrolyzable organosilane is preferably 0.001 to 0.5 mol of water per 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 exceeds 0.5 mol, the stability of the partial hydrolyzate may deteriorate. There is. The method of performing the partial hydrolysis is not particularly limited, and a hydrolyzable organosilane and colloidal silica may be mixed and a necessary amount of water may be added and blended.At this time, the partial hydrolysis reaction proceeds at room temperature,
Heating may be performed at a temperature of 60 to 100 ° C. in order to promote the 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,
Inorganic or organic acids such as maleic acid, malonic acid, toluenesulfonic acid, oxalic acid and the like may be used as a catalyst.

The organic solvent in the organosilane solution is
When the colloidal silica dispersed in an organic solvent is used, the colloidal silica is introduced from the colloidal silica dispersed in the organic solvent. In addition, the colloidal silica may be introduced as an organic solvent added for adjusting the solid content. When the type of the organic solvent in the organosilane solution is introduced from the organic solvent-dispersed colloidal silica, it is the same as described above as the organic solvent for dispersing the colloidal silica, and is introduced as the organic solvent for adjusting the solid content. 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 of 2.0 to 7.0, more preferably 2.5 to 6.5, and still more preferably, in order to obtain stable performance over a long period of time. Is preferably adjusted to a range of pH 3.0 to 6.0. If the pH is out of this range, especially when the amount of water used is 0.3 mol or more with respect to 1 mol of X, the long-term deterioration of the performance of the organosilane solution may be remarkable. pH
Is outside this range, the pH may be adjusted by adding a basic reagent such as ammonia or ethylenediamine if it is more acidic than this range, and hydrochloric acid, nitric acid, or acetic acid if it is more basic than this range. The pH may be adjusted using an acidic reagent such as Of course, the method of this adjustment is not particularly limited.

On the other hand, in consideration of a super-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 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. In addition, 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 based on 100 parts by weight of the organosilane solution. If the addition amount is less than 50 parts by weight, it is difficult to prevent sedimentation of the metal oxide pigment and it is not economically preferable. If it exceeds 200 parts by weight, the dispersion of the metal oxide pigment becomes difficult, and Absent.

In the present invention, at least one of finely divided silica and finely divided alumina is added. Either hydrophilic silica or hydrophobic silica can be used as the fine powdered silica, and commercially available products include “AEROSIL20”, “380”, and “3” manufactured by Nippon Aerosil Co., Ltd.
80PE ", Degussa R972, OK52
0, "TS100", "OK607", "TS720" manufactured by Cabosil, "Nips" manufactured by Nippon Silica Industry Co., Ltd.
il E200 "," E200A "," E22 "
0 "," Same E220A "," ND "," LAPONIT "
EXXL ". Examples of the fine alumina powder include “aluminum oxide C” manufactured by Degussa, Germany.

Although the organosilane solution has almost no viscosity, the viscosity of the system can be increased by adding these fine silica powder or fine alumina powder. The addition amount of the fine powder silica and the fine powder alumina is preferably in the range of 1 to 20 parts by weight based on 100 parts by weight of the organosilane solution. If the added amount is less than 1 part by weight, the effect of adding the fine powdered silica or fine powdered alumina cannot be expected, and if the added amount exceeds 20 parts by weight, the gloss of the coating film decreases. It is not preferable because it becomes significant. By increasing the viscosity of the system by adding fine powder silica or fine powder alumina in this way, the dispersion stability of the metal oxide pigment can be increased, but only by adding fine powder silica or fine powder alumina, It is difficult to prevent and stabilize sedimentation of a metal oxide pigment having a large specific gravity and a large particle diameter for a long period of time. Rather, the addition of finely divided silica or finely divided alumina contributes to the effect of improving redispersibility after storage by interposing finely divided silica or finely divided alumina between particles of the metal oxide pigment. Can be considered. By coexisting with the following metal alkoxide, the effect of improving the 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 a property of reacting with water and hydrolyzing. M = Al, Ti, Zi, etc. OR = methoxy group, ethoxy group, Examples thereof include an isopropoxy group and a butoxy group. In the present invention, aluminum alkoxide, titanium alkoxide, and zirconium alkoxide are used.
Aluminum alkoxide, titanium alkoxide,
One of the zirconium alkoxides may be used, or two or more of these may be used in combination, but from the viewpoint of viscosity, aluminum alkoxides are most preferably used.

By adding these metal alkoxides, the viscosity of the system can be increased. The metal alkoxide is hydrolyzed or partially hydrolyzed by the moisture adsorbed on the metal oxide pigment or the moisture contained in a trace amount in the organosiloxane solution, and a structural viscosity is generated in the dispersion, and the system viscosity is increased. Is thought to increase the viscosity, but the dispersion to which the metal alkoxide is added exhibits very thixotropic properties. For this reason, even if these metal alkoxides are added, they do not affect the dispersion of the metal oxide pigment in the dispersion step. Metal alkoxide is effective with a small amount of addition, and prevents pigment sedimentation over a long period of time even when a metal oxide pigment having a large specific gravity is dispersed in a non-viscous vehicle such as the organosilane solution used in the present invention. It has an amazing effect. By using in combination with the above-mentioned fine powder silica or fine powder alumina, the viscosity can be adjusted and redispersibility can be imparted. What is more effective is that the metal alkoxide consumes the water contained in the organosilane solution that will be the pigment or the vehicle, thereby affecting the vehicle by the water, that is, the condensation polymerization of the organosilane is promoted and the molecular weight is changed. That is, a change in physical properties of the film can be suppressed, which also contributes to the stability of the vehicle itself.

In order to effectively obtain such effects, the amount of the metal alkoxide is preferably in the range of 0.1 to 5 parts by weight, more preferably 0 to 5 parts by weight, based on 100 parts by weight of the organosilane solution. In the range of 3 to 3 parts by weight.
If the addition amount is less than 0.1 part by weight, it is difficult to obtain a stable dispersion, and if it exceeds 5 parts by weight, the viscosity of the dispersion may be too high and handling may be 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, a coating composition having excellent pigment dispersion stability and redispersibility can be prepared. In addition, since the pigment dispersion composition uses the organosilane solution as a vehicle, it is used without any adverse effect on the 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, the above-mentioned organosilane solution or the same organosilane solution except that it does not contain colloidal silica is added. Can be.

And, among the metal oxide pigments, 5-6
By replacing 0 parts by weight with the needle-shaped metal oxide, color separation due to steric hindrance can be prevented by the needle-shaped metal oxide. Is obtained, and as a result,
Cracking properties can be remarkably enhanced while maintaining high redispersibility and color stability.

The amount of the acicular metal oxide is preferably 20 to 60 parts by weight, more preferably 45 to 60 parts by weight.
It is 55 parts by weight, and by replacing a part of the metal oxide pigment with such an amount of the acicular metal oxide, the cracking property can be more effectively strengthened.

If less than 5 parts by weight of the metal oxide pigment is replaced with needle-like metal oxide, the amount of needle-like metal oxide is too small, and as a result, the cracking property is markedly increased. The effect cannot be obtained as much as possible, and conversely, if the metal oxide pigment is replaced with more than 60 parts by weight of acicular metal oxide, the amount of acicular metal oxide Is too large, as a result, the dispersibility is reduced, and it is difficult to maintain high redispersibility, color stability, and the like.

Examples of the acicular metal oxide include acicular titanium oxide, acicular aluminum oxide, acicular barium sulfate, acicular magnesium sulfate, acicular potassium titanate and the like.

Next, a coating composition using the above pigment dispersion composition will be described. The coating composition is generally prepared by blending a base material, a curing agent, a catalyst for accelerating the reaction between the base material and the curing agent, and a pigment.In the present invention, instead of directly blending a pigment, By blending a pigment dispersion composition in which a pigment is dispersed in advance as described above as a main ingredient, a coating composition in which a pigment is stably dispersed can be obtained.

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

In the formula (2), R ² represents 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, a 3,3 , 3-trifluoropropyl and the like, 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, a +
a number satisfying the relationship of b <4, where a is less than 0.2 or b
Is more than 3, there are inconveniences such as cracks in the cured film, and when a is more than 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, and the corresponding alkoxysilane. It can be obtained by hydrolyzing the above mixture with a large amount of water by a known method. When a silanol group-containing polyorganosiloxane is hydrolyzed by a known method using alkoxysilane, a small amount of an unhydrolyzed alkoxy group 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 and the curing agent in the pigment dispersion composition as the main component and curing the coating. Examples of the catalyst include metal salts of carboxylic acids such as alkyl titanates, tin octylate and dibutyltin dilaurate and dioctyltin dimaleate; amine salts such as dibutylamine-2-hexoate, dimethylamine acetate, ethanolamine acetate; tetramethyl acetate Amines such as quaternary ammonium salts of carboxylic acids such as ammonium and amines such as tetraethylpentamine; amine-based silane coupling agents such as N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane and ethylenediaminemethylpropyldimethoxysilane; p
Acids such as toluenesulfonic acid, phthalic acid and hydrochloric acid; aluminum compounds such as aluminum alkoxide and aluminum chelate; alkali catalysts such as potassium hydroxide;
Titanium compounds such as tetraisopropyl titanate, tetrabutyl titanate, and titanium tetraacetylacetonate; halogenated silanes such as methyltrichlorosilane, dimethyldichlorosilane, and trimethylmonochlorosilane; and the like, as well as silica-dispersed oligomers of organosilanes There is no particular limitation as long as it is effective for the condensation reaction between the polymer and the curing agent.

The blending ratio between 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 amount of the polyorganosiloxane component in the curing agent to 99 to 1 part by weight based on 1 to 99 parts by weight, and more preferably 5 to 95 parts by weight of the polyorganosiloxane component in the curing agent. 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 (provided that 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 copolymerized surfactant, an amine-based surfactant, and an ester-based surfactant, and are particularly suitable for the present invention. As the surfactant, a carboxylic acid-based surfactant, a polymer copolymer-based surfactant, and an amine-based surfactant are preferable. Its commercial products include Byk-Chemi
e “Byk-P104”, “P104S”, “2
40S "," Disperbyk-160 "," Dis
perbyk-161 "," Disperbyk-16 "
2 "," Disperbyk-163 "," Dispe
rbyk-164 "," Disperbyk-16 "
5, "Disperbyk-166", "Anti-
Terra-203 "," Disperbyk "," D
isperbyk-181 "and the like. It is difficult to secure color stability with other surfactants. The amount of the surfactant is based on 100 parts by weight of the pigment dispersion composition.
It is 0.05 to 5 parts by weight, preferably 0.05 to 1.6 parts by weight, and most preferably 1.1 to 1.6 parts by weight. When the amount of the surfactant is less than 0.05 part by weight, the effect of preventing color separation becomes insufficient, and when the amount exceeds 5 parts by weight, the pigments 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 a cellulose resin, an acrylic silicone resin, a silicone resin, a fluorine resin, an acrylic resin, and a 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 cellulosic resins include "Ethocel STD-45" and "Ethocel STD-100" manufactured by Dow Chemical Company, and commercially available acrylic silicone resins include "LY" manufactured by Dainippon Ink and Chemicals, Inc. -805 "," VY-108 ",
Commercially available silicone resins such as "VY-109" include "TSR116" and "TSR116" manufactured by Toshiba Silicone Co., Ltd.
117 ”and the like are commercially available fluororesins such as“ VE471 ”manufactured by Daikin Industries, and“ LF-20 ”manufactured by Asahi Glass.
0 "and" N-75 "manufactured by Sumitomo Chemical Co., Ltd. Other resins may not be well compatible in the pigment dispersion composition, or may not provide a significant effect of preventing pigment sedimentation. The amount of the resin is 0.05 to 20 parts by weight, preferably 0.55 parts by weight, per 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 is less than 0.05 part by weight, the effect of preventing the sedimentation of the pigment becomes insufficient, and if it exceeds 20 parts by weight, the paint may be excessively thickened and the smoothness of the coating film may be lost. .

Thus, the coating composition according to the present invention can be used for a steel base 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 plastic base. By coating on 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. For example, various coating methods such as brush coating, spraying, dipping, flow, roll, curtain, and knife coating can be selected.

[0054]

Next, the present invention will be further described with reference to examples. Unless otherwise specified in the examples, all parts are by weight.
And “%” represents “% by weight” in all cases. It goes without saying that the present invention is not limited to these examples.

(Example 1) 34.09 parts of methyltrimethoxysilane (manufactured by Toshiba Silicone Co., Ltd.) was mixed with methanol-dispersed colloidal silica sol ("MA-S" manufactured by Nissan Chemical Industries, Ltd.).
T ") An organosilane solution was prepared by adding 0.40 part of water in 47.62 parts and hydrolyzing. Then, based on 100 parts by weight of the organosilane, 60 parts of titanium oxide as a metal oxide pigment, 59 parts of acicular titanium oxide as an acicular metal oxide, and fine powdered silica ("AEROSIL 380PE" manufactured by Nippon Aerosil Co., Ltd.) 2.5 And 0.5 parts of aluminum isopropoxide as an aluminum alkoxide, and the pigment was dispersed with a Dynomill so as to have a dispersity of 10 μ or less to obtain a pigment dispersion composition liquid.

Observation of the state of the pigment dispersion composition after standing for 6 months showed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

Further, when the state of the pigment dispersion composition liquid after standing for 9 months was observed, no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

Next, this pigment dispersion composition liquid was evaluated by a warm water air drying test 1, a warm water air drying test 2, an initial adhesion test, and color stability.

The hot water air drying test 1 is a cycle in which a coating film obtained by applying the pigment dispersion composition liquid is immersed in warm water of 60 ° C. for 8 hours and further air-dried for 16 hours. In each case, the presence or absence of cracks in the coating film was determined for each of 10 cycles and 15 cycles.

The hot water air drying test 2 is a cycle in which a coating film obtained by applying the same pigment dispersion composition liquid is immersed in warm water of 80 ° C. for 8 hours and further air-dried for 16 hours. In each case, the presence or absence of cracks in the coating film was determined for each of 10 cycles and 15 cycles.

As the initial adhesion test, a JIS cross-cut adhesion test was conducted. The color stability was determined by spraying the pigment dispersion composition liquid on an aluminum plate and applying the paint immediately after coating. This shows the color difference after a month has passed.

As a result, the hot-water air-drying test 1 was performed for both 10 cycles and 15 cycles.
No cracks occurred. Also, in the hot water air drying test 2, cracks did not occur either in the case where 10 cycles were performed or in the case where 15 cycles were performed. The results of the initial adhesion test were good, and the color stability was ΔE <0.3.

Example 2 34.09 parts of methyltrimethoxysilane (manufactured by Toshiba Silicone Co., Ltd.) was mixed with methanol-dispersed colloidal silica sol (“MA-S” manufactured by Nissan Chemical Industries, Ltd.).
T ") An organosilane solution was prepared by adding 0.40 part of water in 47.62 parts and hydrolyzing. Then, with respect to 100 parts by weight of the organosilane, 60 parts of titanium oxide and 29 parts of oker (iron oxide ("LLXLO" manufactured by Titanium Industry Co., Ltd.)) as a metal oxide-based pigment, and 30 parts of acicular titanium oxide as acicular metal oxide Part, fine powder silica (“AEROSIL380PE” manufactured by Nippon Aerosil Co., Ltd.)
2.5 parts and 0.5 parts of aluminum isopropoxide as an aluminum alkoxide were blended, and the pigment was dispersed with a Dynomill so as to have a dispersity of 10 μ or less to obtain a pigment dispersion composition liquid.

When the state of the pigment dispersion composition liquid after standing for 6 months was observed, no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

Further, when the state of the pigment dispersion composition liquid after standing for 9 months was observed, no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

Next, in the same manner as in Example 1, this pigment dispersion composition liquid was evaluated by a warm water air drying test 1, a warm water air drying test 2, an initial adhesion test, and color stability.

As a result, the hot-water air-drying test 1 was performed for both 10 cycles and 15 cycles.
No cracks occurred. Also, in the hot water air drying test 2, cracks did not occur either in the case where 10 cycles were performed or in the case where 15 cycles were performed. The results of the initial adhesion test were good, and the color stability was ΔE <0.3.

(Example 3) 100 parts of the pigment dispersion composition obtained in Example 2, 46.6 parts of the organosilane solution (referred to as red down resin) obtained in Example 1, and polycarboxylic acid as a surfactant Surfactant (Byk-Chemie)
After mixing 1.6 parts of "BYK-P104" (manufactured by KK) and sufficiently stirring with a disper, 4.07 parts of ethylenediaminemethylpropyldimethoxysilane and 0.81 part of dibutyltin dilaurate were added as catalysts, and the mixture was further sufficiently added. Stirred. Thereafter, 23.4 parts of a 14% toluene solution of ethyl cellulose (“Ethocel STD-100” manufactured by Dow Chemical Co., Ltd.) was used as the cellulose resin (“Ethocel STD-100”).
100 "was added in 3.2 parts), and the mixture was sufficiently stirred with a disper to obtain a main ingredient of the coating composition. This base material was extremely unlikely to cause pigment sedimentation, and even if it did, was very excellent in redispersibility.

Observation of the state of the main ingredient 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.

Further, when the state of the main agent after standing for 9 months was observed, no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

Next, in the same manner as in Example 1, this base material was subjected to a warm water air drying test 1, a warm water air drying test 2, an initial adhesion test,
Evaluation was made by color stability.

As a result, the hot-water air-drying test 1 showed that both the cases where 10 cycles were performed and the cases where 15 cycles were performed,
No cracks occurred. Also, in the hot water air drying test 2, cracks did not occur either in the case where 10 cycles were performed or in the case where 15 cycles were performed. The results of the initial adhesion test were good, and the color stability was ΔE <0.3.

(Comparative Example 1) 34.09 parts of methyltrimethoxysilane (manufactured by Toshiba Silicone Co., Ltd.) was dispersed in methanol-colloidal silica sol (“MA-S” manufactured by Nissan Chemical Industries, Ltd.).
T ") An organosilane solution was prepared by adding 0.40 part of water in 47.62 parts and hydrolyzing. Then, based on 100 parts by weight of the organosilane, 119 parts of titanium oxide as a metal oxide-based pigment and fine powder silica (“AEROSIL 380PE” manufactured by Nippon Aerosil Co., Ltd.)
2.5 parts and 0.5 parts of aluminum isopropoxide as an aluminum alkoxide were blended, and the pigment was dispersed with a Dynomill so as to have a dispersity of 10 μ or less to obtain a pigment dispersion composition liquid.

When the state of the pigment dispersion composition liquid after standing for 6 months was observed, no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

However, when the state of the pigment dispersion composition liquid after standing for 9 months was observed, a slight hard cake was formed and the pigment dispersion stability was somewhat poor. Agglomerates were observed as redispersibility of the pigment, which was poor.

Next, in the same manner as in Example 1, this pigment dispersion composition liquid was evaluated by a warm water air drying test 1, a warm water air drying test 2, an initial adhesion test, and color stability.

As a result, in the hot water air drying test 1, no crack was generated after 10 cycles, but fine cracks were generated after 15 cycles. In the hot water air drying test 2, cracks did not occur when 10 cycles were performed, but fine cracks occurred when 15 cycles were performed. The results of the initial adhesion test were good, and the color stability was 0.8 <ΔE <1.0.

Comparative Example 2 100 parts of the pigment dispersion composition obtained in Comparative Example 1, 46.6 parts of the organosilane solution (referred to as red down resin) obtained in Example 1, and polycarboxylic acid as a surfactant Surfactant (Byk-Chemie)
After mixing 1.6 parts of "BYK-P104" (manufactured by KK) and sufficiently stirring with a disper, 4.07 parts of ethylenediaminemethylpropyldimethoxysilane and 0.81 part of dibutyltin dilaurate were added as catalysts, and the mixture was further sufficiently added. Stirred. Thereafter, 23.4 parts of a 14% toluene solution of ethyl cellulose (“Ethocel STD-100” manufactured by Dow Chemical Co., Ltd.) was used as the cellulose resin (“Ethocel STD-100”).
100 "was added in 3.2 parts), and the mixture was sufficiently stirred with a disper to obtain a main ingredient of the coating composition.

Observation of the state of the main agent after standing for 6 months showed that no hard cake was formed and the pigment dispersion stability was good. The redispersibility of the pigment was also good.

However, when the state of the main ingredient after standing for 9 months was observed, a little hard cake was formed and the pigment dispersion stability was somewhat poor. Agglomerates were observed as redispersibility of the pigment, which was poor.

Next, in the same manner as in Example 1, this base material was subjected to a warm water air drying test 1, a warm water air drying test 2, an initial adhesion test,
Evaluation was made by color stability.

As a result, in the hot water air drying test 1, no crack was generated after 10 cycles, but fine cracks were generated after 15 cycles. In the hot water air drying test 2, cracks did not occur when 10 cycles were performed, but fine cracks occurred when 15 cycles were performed. The results of the initial adhesion test were good, and the color stability was 0.8 <ΔE <1.0.

The main components of the pigment dispersion composition and the coating composition obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated for pigment dispersion stability, redispersibility, hot water air drying test 1, warm water air drying test 2, Table 1 summarizes the results of the initial adhesion test and the evaluation of each performance of color stability.

[0084]

[Table 1]

In Table 1, regarding the pigment dispersion stability, when the state after standing for 9 months was observed, the state where no hard cake was formed and good was evaluated as “○”, and the state after standing for 6 months was observed. As a result, although the hard cake was not formed and the condition was good after observation for 9 months, the hard cake was slightly formed and the poor one was indicated by "表示". Regarding the redispersibility, the state after standing for 9 months was good. That is, when a sedimentation layer was formed, it was evaluated using a stirrer.
When the sedimentation layer disappeared by stirring for a minute, "○", and the state after standing for 6 months was observed, and although good, the state after standing for 9 months was observed.
The bad ones are indicated by "△".

In Table 1, in each of the hot-water air-dry test 1 and the hot-water air-dry test 2, in each of the case where the test was performed for 10 cycles and the case where the test was performed for 15 cycles, “O” indicates that no crack was generated. Cracks did not occur when the cycle was performed, but those where fine cracks occurred when the cycle was performed for 15 cycles are indicated by “△”.

In Table 1, since all of the initial adhesion tests were good, they were indicated by “○”.

Further, in Table 1, regarding the color stability, those having a small color difference between immediately after coating and after 6 months, that is, those with ΔE <0.3 were evaluated as “○”, A color difference slightly after a lapse of months, that is, a color difference of 0.8 <ΔE <1.0 was indicated by “Δ”.

As can be seen from Table 1 and the above, all of Examples 1 to 3 were maintained while maintaining the initial adhesion.
Are superior to those of Comparative Examples 1 and 2. Among the metal oxide pigments, 5 to 60 parts by weight of the metal oxide pigment were replaced with acicular metal oxides. Prevents color separation due to obstacles, and also has good redispersibility and can provide paint stability over a long period of time, resulting in high redispersibility and color stability. It can be said that the cracking property can be remarkably strengthened by maintaining as it is.

[0090]

As described above, the pigment dispersion composition according to the present invention has a general formula R ¹ _n SiX _4-n (wherein R ¹ is the same or different and is substituted or unsubstituted having 1 to 8 carbon atoms). Wherein n is an integer of 0 to 3 and X is a hydrolyzable group, wherein a hydrolyzable organosilane represented by the following formula: is partially dissolved in colloidal silica dispersed in an organic solvent or water. An organosilane solution obtained by hydrolysis and comprising an organosilane silica-dispersed oligomer solution and an organic solvent,
Metal oxide pigments, at least one of finely divided silica and finely divided alumina, and at least one of aluminum alkoxide, titanium alkoxide and zirconium alkoxide, respectively, are added. The sedimentation of the pigment can be prevented, and the redispersibility of the pigment can be improved by the action of fine silica powder or fine alumina powder. It can stably disperse over the entire area and can obtain good redispersibility, and because it contains organosilane as a main component, 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. In addition, by replacing 5 to 60 parts by weight of the metal oxide pigment with the acicular metal oxide, color separation due to steric hindrance can be prevented with the acicular metal oxide. In addition, the redispersibility is good, and the stability of the paint can be obtained over a long period of time. As a result, it is possible to maintain the redispersibility and color stability at a high level, and to remarkably enhance the cracking property. You can do it.

That is, the present invention can remarkably enhance cracking properties while maintaining high redispersibility and color stability.

The coating composition according to the present invention comprises the above-described pigment dispersion composition, at least one of a surfactant and a resin, a catalyst, and a curing agent. The color stability can be ensured and the storage stability can be increased.Moreover, since the pigment is dispersed in the pigment dispersion composition in advance, the pigment dispersion at the time of preparing the coating composition is reduced. The process can be omitted, and the productivity can be improved.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 151/08 C09D 151/08

Claims (8)

[Claims] (1) The general formula is R ¹ _n SiX _4-n (wherein R ¹
Represents a same or different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, n represents an integer of 0 to 3, and X represents a hydrolyzable group. Is obtained by partially hydrolyzing in colloidal silica dispersed in an organic solvent or water, a metal oxide pigment, finely divided silica is added to an organosilane solution comprising an organosilane silica-dispersed oligomer solution and an organic solvent. And a pigment dispersion composition comprising at least one of aluminum alkoxide, titanium alkoxide, and zirconium alkoxide.
A pigment dispersion composition in which 60 parts by weight have been replaced with needle-like metal oxides. 2. A metal oxide pigment is added in an amount of 50 to 200 parts by weight, and at least one of fine powdered silica and fine powdered alumina is used in an amount of 1 to 20 parts by weight based on 100 parts by weight of the organosilane solution.
2. The pigment dispersion according to claim 1, wherein the pigment dispersion composition is obtained by adding 5 parts by weight of the metal oxide pigment, and 5 to 60 parts by weight of the metal oxide pigment is replaced with a needle-shaped metal oxide. 3. Composition. 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 according to the above. 4. A coating composition comprising: the pigment dispersion composition according to claim 1; 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} (wherein, R ² represents the same or different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and a and b each represent 0.2 ≦ a <2.0, 0.0
001 ≦ b ≦ 3, a + b <4)
The coating composition according to claim 4, which is a polyorganosiloxane containing a silanol group in a molecule represented by the following formula: 6. The coating composition according to claim 4, wherein a resin selected from the group consisting of a cellulose resin, an acrylic silicone resin, a silicone resin and a fluorine resin is used. 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.