JPH0559299A - Zro2-cao coating composition - Google Patents

Abstract

PURPOSE:To obtain a coating composition capable of long-term storage and readily forming films excellent in thermal resistance, wear resistance, water resistance and chemical resistance on various materials including metals, plastics, wood, paper, cement and graphite. CONSTITUTION:The title composition comprises a zirconium tetraalkoxide, a calcium compound selected from the group consisting of calcium nitrate, calcium chlorate and calcium perchlorate, an alcohol compound selected from the group consisting of 2-hydroxy alcohol, 2-oxo alcohol, 3-hydroxyalcohol, 3-oxo alcohol, alpha-diol and beta-diol, and an organic solvent.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a ZrO ₂ --CaO system
Coating composition.

[0002]

2. Description of the Related Art Conventionally, metal, plastic, wood, paper,
Heat resistance, abrasion resistance, and heat resistance on materials such as cement and graphite.
In order to improve water resistance, chemical resistance, etc., a coating film is formed by coating, and a typical coating method is, for example, an organic method using a silicone resin as a binder. Coating with paint can be mentioned. However, the coating film obtained from the above organic coating is
It has poor heat resistance and cannot withstand long-term use in an atmosphere of 200 ° C or higher.

On the other hand, it has been proposed to coat a ceramic thin film having heat resistance on a material, and at present, it is mainly applied to a metal material. Examples of the coating method include vapor deposition method, sputtering method, CVD method,
Examples of the coating method include the thermal spraying method and the like.
There is a drawback that the material, size, shape and the like of the raw material are largely limited and the coating operation is complicated.

In order to solve the above-mentioned drawbacks, there has been proposed a zircon composition which has no limitation on the material and which can be easily coated on the material having various sizes and shapes. JP 61-250063 discloses Zr.
A composition obtained by mixing a zirconium compound represented by (OC ₄ H ₉ ) ₄ , ethyl silicate and isopropyl alcohol is described, and JP-A-63-190175 discloses a composition.
A composition consisting of a zirconium oxyacid salt, a silicon alkoxide or a derivative thereof, water and an organic solvent is described. However, the above composition has a drawback that the long-term storage stability is poor, and that the coating film obtained by coating on the material is apt to cause cracks and peeling.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks, and an object thereof is to enable easy coating and obtain a coating film having excellent stability and long-term storability. It is intended to provide a ZrO ₂ —CaO based coating composition.

[0006]

The zirconium tetraalkoxide (a) used in the present invention has the general formula Zr (OR
¹ ) ₄ is a compound represented by the formula, wherein R ¹ represents an alkyl group, but when the number of carbon atoms increases, the stability of the ZrO ₂ —CaO based coating composition decreases and the long-term storage stability deteriorates. Therefore, the carbon number is limited to 1 to 5.

The above zirconium tetraalkoxide (a)
As, for example, zirconium tetramethoxide, zirconium tetraethoxide, zirconium tetra-n-
Examples include propoxide, zirconium tetra-iso-propoxide, zirconium tetra-n-butoxide, zirconium tetra-sec-butoxide, zirconium tetra-tert-butoxide, and the like, particularly zirconium tetra-n-butoxide and zirconium tetra-iso-propoxy. Is preferred. These may be used alone or in combination of two or more.

Calcium compound (b) used in the present invention
Is a compound selected from the group consisting of calcium nitrate, calcium chlorate and calcium perchlorate, and examples of the calcium compound (c) include anhydrous calcium nitrate, calcium nitrate dihydrate, anhydrous calcium chlorate, and chlorine. Examples thereof include calcium acid dihydrate, anhydrous calcium perchlorate, calcium perchlorate tetrahydrate and the like, and anhydrous calcium nitrate, anhydrous calcium chlorate and anhydrous calcium perchlorate are particularly preferable. These may be used alone or in combination of two or more.

If the amount of the above calcium compound (b) added to the zirconium tetraalkoxide (a) is small or large, cracks are likely to occur in the coating film obtained, and therefore the calcium compound (b) / zirconium tetraalkoxide (z) is added. The alkoxide (a) (molar ratio) is preferably 0.01 to 2.5, more preferably 0.1 to 2.0.

The alcohol compound (c) used in the present invention
Is 2-oxyalcohol, 2-oxoalcohol, 3
-One or more compounds selected from the group consisting of oxyalcohol, 3-oxoalcohol, α-diol and β-diol.

Examples of the 2-oxyalcohol include 2-methoxyethanol and 2-ethoxyethanol.
And 2- (1-methylethoxy) ethanol, 1-methoxy-2-propanol, diethylene glycol, tetrahydrofurfuryl alcohol and the like. Examples of 2-oxo alcohol include 2 -Oxo-1-propanol, furfural, ethyl lactate, and the like, including 3
Examples of -oxyalcohol include 3-methoxypropanol and 2- (2-hydroxyethyl) furan, and examples of 3-oxoalcohol include 2
-Oxo-1-butanol, ethyl 3-hydroxybutyrate and the like, and examples of the α-diol include ethylene glycol, propylene glycol and the like, β
Examples of -diol include propanediol, butanediol, 2,4-pentanediol and the like.

When the amount of the above-mentioned alcohol compound (c) added to the zirconium tetraalkoxide (a) is small, the stability of the ZrO ₂ -CaO coating composition is lowered and the long-term storage stability is deteriorated. If so, the resulting coating film is likely to crack, so the alcohol compound (c)
/ Zirconium tetraalkoxide (a) (molar ratio) is preferably 0.5 to 6.

The organic solvent (d) used in the present invention is compatible with the zirconium tetraalkoxide (a),
The calcium compound (b) is not particularly limited as long as it exhibits solubility, for example, methyl alcohol,
Examples thereof include alcohols such as ethyl alcohol, isopropyl alcohol and butyl alcohol, ketones such as acetone and methyl ethyl ketone, and tetrahydrofuran. Methyl alcohol, ethyl alcohol and isopropyl alcohol are particularly preferable. These may be used alone or in combination of two or more.

When the amount of the organic solvent (d) added is small, the stability of the ZrO ₂ -CaO coating composition is low and the long-term storage stability is poor, and when it is large, pinholes are added to the resulting coating film. Is likely to occur, organic solvent (d) / [zirconium tetraalkoxide (a) + calcium compound
(b)] (molar ratio) is preferably from 0.05 to 500, more preferably from 0.2 to 300.

The method for producing the ZrO ₂ -CaO coating composition of the present invention is not particularly limited,
For example, a method of collectively mixing the above-mentioned constituent materials, a method of dividing and mixing a specific constituent material, and then adding the remaining constituent materials and mixing, etc., the latter method is preferable, for example, A method of mixing the zirconium tetraalkoxide (a), the alcohol compound (c) and the organic solvent (d) as a specific constituent material and then adding the calcium compound (b) is adopted. Next, ZrO ₂ -C of the present invention 2
The aO-based coating composition will be described.

In the composition of the present invention 2, in place of the amine compound (d), one or more ketone compounds selected from the group consisting of β-diketones and β-ketoesters.
(c) is used.

Examples of the β-diketone include acetylacetone, benzoylacetone, dibenzoylmethane, 3-methylpentane-2,4-dione, diacetone alcohol and the like, and β-ketoesters include
For example, methyl acetoacetate, ethyl acetoacetate, methyl benzoyl acetate, ethyl benzoyl acetate and the like can be mentioned.

When the amount of the above-mentioned ketone compound (c) added to the zirconium tetraalkoxide (a) decreases, Z decreases.
Since the stability of the rO ₂ -CaO coating composition is deteriorated and the long-term storage stability is deteriorated, and when the coating composition is increased, cracks are likely to occur in the coating film, the ketone compound (c) / zirconium tetraalkoxide (a) (Molar ratio) is 0.5-6
Is preferred.

The composition of the present invention and the ZrO ₂ —CaO coating composition of the present invention 2 are as described above, but the stability (crack resistance, peeling resistance, etc.) of the obtained coating film is further improved. CaZrO ₃ powder may be added to do so.

When the average particle size of the above CaZrO ₃ powder is small, it becomes difficult to disperse it in the ZrO ₂ -CaO coating composition, and when it is large, cracks are likely to occur in the resulting coating film. 01 to 100 μm is preferable, and 0.02 to 10 μm is particularly preferable.

The above CaZrO₃Powder ZrO₂-CaO system
When the amount added to the coating composition was small, it was obtained.
The degree of improvement in the stability of the coating film decreases and increases.
And ZrO₂-CaO coating composition has reduced stability
As the long-term storage stability deteriorates, all ZrO₂-CaO acid
Compounds (zirconium tetraalkoxide (a) and calcium
Oxide formed from sium compound (b) and the above Ca
ZrO₃The total amount of powder) is preferably 1 to 60% by weight.
In addition, CaZrO₃The addition of the powder is based on ₂-CaO
After mixing the constituent materials of the coating composition
Preferably.

The ZrO ₂ -CaO-based coating composition of the present invention is coated or impregnated on the above-mentioned material and dried to obtain ZrO ₂ -CaO-based coating composition.
An rO ₂ —CaO based oxide film is formed. The application method is not particularly limited, and for example, a brush,
Spray coat, dip coat, spin coat, roll
An example of the coating method is a coat method.

The impregnation method is not particularly limited, and examples thereof include a method of immersion impregnation under normal pressure and a method of immersion impregnation under reduced pressure, and the immersion impregnation under reduced pressure is preferable.

The drying method is not particularly limited, and may be naturally dried at room temperature or may be dried by heating. Moreover, after drying, you may heat-process at high temperature as needed.

[0025]

EXAMPLES Examples of the present invention will be described below. The methods for evaluating the physical properties of the ZrO ₂ —CaO coating composition shown in the results are as follows.

(1) Initial Adhesion A slide glass (manufactured by Matsunami Co., Ltd.) ultrasonically cleaned with acetone was dipped in the obtained ZrO ₂ —CaO coating composition and pulled up at a speed of 300 mm / min. After that, it is dried under the following conditions to form a ZrO ₂ —CaO-based oxide coating layer to prepare an evaluation sample, and a cross-cut tape peeling test is performed according to JIS D 0202 to obtain 100 ZrO ₂ -CaO
The ratio (adhesion rate) of the remaining meshes to the meshes of the system oxide coating layer was measured and evaluated.

(Drying conditions) Initial drying: 25 ° C., 24 hours Final drying: 500 ° C. (temperature rising from 25 ° C. to 50 ° C./hr),
Hold for 2 hours

(2) Pencil hardness Using the obtained ZrO ₂ —CaO coating composition, an evaluation sample was prepared in the same manner as in the case of evaluating the above initial adhesion, and measured according to JIS K 5400. did.

(3) Boiling water resistance (crack resistance and adhesion durability) Evaluation was carried out in the same manner as the above-mentioned initial adhesion was evaluated using the obtained ZrO ₂ -CaO coating composition. After immersing the sample in boiling water for 8 hours, the state of the surface was subjected to a sensory test to evaluate crack resistance according to the following criteria.

(Judgment Criteria) ◯: No crack on the surface X: Crack on the surface The adhesion durability was evaluated by the rate.

(4) Acid resistance (crack resistance and adhesion durability) An evaluation sample prepared by using the obtained ZrO ₂ —CaO coating composition in the same manner as in the case of evaluating the above initial adhesion. Was immersed in 20 wt% hydrochloric acid for 75 hours, and the surface condition was subjected to a sensory test to evaluate crack resistance according to the following criteria.

(Judgment Criteria) ◯: No cracks on the surface x: Cracks on the surface After performing the above-mentioned sensory test, a cross-cut tape peeling test was performed in the same manner as in the case of evaluating the above-mentioned initial adhesion. The adhesion durability was evaluated by the rate.

(5) Long-term storability The sealed container containing the obtained ZrO ₂ —CaO coating composition was left in an atmosphere of 50 ° C. and 65% RH for 3 months, and then the initial adhesion was maintained. An evaluation sample was prepared in the same manner as the evaluation, a cross-cut tape peeling test was performed, and the long-term storability was evaluated according to the following criteria.

(Judgment Criteria) A: Adhesion ratio exceeds 80% X: Adhesion ratio is 80% or less

(Examples 1 to 13) A predetermined amount of zirconium tetraalkoxide, an alcohol compound and ethyl alcohol shown in Table 1 were supplied to a separable flask,
The mixture was stirred at room temperature for 15 hours at a stirring speed of 800 rpm to obtain a stabilized zirconium tetraalkoxide alcohol solution.

A predetermined amount of the calcium compound shown in Table 1 was added to the obtained alcohol solution, and the mixture was stirred at room temperature for 24 hours at a stirring speed of 800 rpm to obtain a ZrO ₂ -CaO coating composition. ..

Using the obtained ZrO ₂ —CaO coating composition, each physical property was measured according to the above-mentioned measuring method,
The results are shown in Table 1.

Example 14 A ZrO ₂ —CaO-based coating composition obtained in the same manner as in Example 1 was added with all ZrO.
₂ -CaO-based oxide (oxides formed from zirconium tetra-alkoxide and calcium compounds, and CaZrO ₃ total amount of powder) an amount of CaZrO ₃ powder corresponding to 10% by weight (average particle size 1 [mu] m) was added, Stir at a stirring speed of 1000 rpm for 1 hour at room temperature to CaZrO.
_A ZrO ₂ —CaO based coating composition containing ₃ powders was obtained. Using the obtained CaZrO ₃ powder-containing ZrO ₂ —CaO coating composition, each physical property was measured based on the above-mentioned measuring methods, and the results are shown in Table 1.

[0039]

[Table 1]

(Comparative Examples 1 to 8)
Ruconium tetraalkoxide, alcohol compound,
Example using a chill alcohol and a calcium compound
ZrO as in 1 ₂-CaO based coating composition
Obtained. The obtained ZrO₂-CaO based coating composition
Based on the above measurement method, each physical property is measured and the result is
The results are shown in Table 2.

[0041]

[Table 2]

(Examples 15 to 23) A ZrO ₂ -CaO coating composition was prepared in the same manner as in Example 1 except that the specified amounts of zirconium tetraalkoxide, ketone compound, ethyl alcohol and calcium compound shown in Table 3 were used. I got a thing. Using the obtained ZrO ₂ —CaO based coating composition, each physical property was measured based on the above-mentioned measuring method, and the results are shown in Table 3.

[0043]

[Table 3]

[0044]

The composition of the ZrO ₂ -CaO coating composition of the present invention is as described above, and zirconium tetraalkoxide stabilized with a specific alcohol compound or ketone compound, and a calcium compound and Since it contains a specific amount of organic solvent, it can be stored for a long period of time, and it has heat resistance, abrasion resistance, water resistance and chemical resistance on various materials such as metal, plastic, wood, paper, cement and graphite. A coating film having excellent properties can be easily formed.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C23C 18/12 8414-4K

Claims (2)

[Claims] 1. A zirconium tetraalkoxide represented by (a) a general formula Zr (OR ¹ ) ₄ (wherein R ¹ is an alkyl group having 1 to 5 carbon atoms), (b) calcium nitrate, calcium chlorate and A calcium compound selected from the group consisting of calcium perchlorate, (c) 2-oxyalcohol, 2-oxoalcohol, 3
ZrO ₂ -CaO, characterized in that it comprises an alcohol compound selected from the group consisting of -oxyalcohol, 3-oxoalcohol, α-diol and β-diol, and (d) an organic solvent. Based coating composition. 2. The ZrO ₂ —CaO coating composition according to claim 1, wherein the alcohol compound (c) is replaced by
ZrO ₂ -using a ketone compound selected from the group consisting of β-diketones and β-ketoesters
CaO-based coating composition.