JP2011148844A - Organic polysilazane coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic polysilazane coating which can form uniform coating films. <P>SOLUTION: The organic polysilazane coating is characterized by containing an organic polysilazane and a silicone oil. Therein, the silicone oil is preferably dimethylsilicone oil, and the organic polysilazane is preferably either or a mixture of methylpolysilazane and dimethylpolysilazane. Thereby, uniform coating films can easily be formed from the organic polysilazane, and the coating films excellent in an antistaining property, a stain-removing property, and the like can easily be obtained due to the characteristics, such as water repellency and oil repellency, of the coating films of the organic polysilazane. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention includes gas appliances such as gas stoves, water heaters, gas stoves, oil fan heaters, oil heaters such as oil stoves, IH cooking heaters, electric cooking appliances such as microwave ovens, or porcelain tiles, natural stone, glass, plastic, The present invention relates to an organic polysilazane coating used for preventing contamination and protecting a surface of an object made of various materials such as ceramic, metal, concrete, mortar and brick.

Conventionally, as a paint using an organic polysilazane as a binder, for example, an oil solvent, an aromatic or cycloaliphatic solvent, an ether, a halogenated hydrocarbon, a terpene mixture, or a mixture of these solvents as a diluent. Some have been used (see Patent Document 1). These diluents are a kind of volatile organic solvents.
However, in organic polysilazane paints using such volatile organic solvents, countermeasures against volatile organic solvents being discharged into the atmosphere, or manufacturing workers or paints that may inhale volatile organic solvents. It was necessary to take measures to maintain the health of workers. In addition, these volatile organic solvents remain in the dried coating film of the organic polysilazane coating, thereby inhibiting hydrolysis of the organic polysilazane, resulting in a non-uniform coating film in which the formation of Si—O bonds is not sufficient. Various physical properties such as anti-contamination, decontamination, chemical resistance, and surface hardness may be reduced. These reductions in physical properties were particularly remarkable at the initial stage of film formation.

JP 2006-515641 A (pages 2 to 3)

An object of this invention is to provide the organic polysilazane coating material which can form a uniform coating film.

The invention according to claim 1 is characterized in that it contains organic polysilazane and silicone oil.

The invention described in claim 2 is characterized in that, in the invention described in claim 1, the silicone oil contains dimethyl silicone oil.

The invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the organic polysilazane includes one of methylpolysilazane and dimethylpolysilazane, or a mixture of both.

The invention according to claim 4 is characterized in that, in the invention according to any one of claims 1 to 3, the organic polysilazane contains 0.1 to 30% by mass of a cyclic product.

The invention according to claim 5 is characterized in that, in the invention according to any one of claims 1 to 4, the kinematic viscosity at 25 ° C. of the silicone oil is 0.2 to 10 mm ² / s. To do.

The invention according to claim 6 is characterized in that the organic polysilazane paint according to any one of claims 1 to 5 is applied after the undercoat paint is applied to the object to be coated.

  According to the first aspect of the present invention, there is an advantage that uniform coating formation with an organic polysilazane is facilitated.

According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, there is an advantage that the drying property of the organic polysilazane paint can be improved.

According to invention of Claim 3, in addition to the effect of the invention of Claim 1 or 2, there exists an advantage that oil repellency can be improved.

According to invention of Claim 4, in addition to the invention in any one of Claims 1-3, there exists an advantage that heat resistance can be improved.

According to the invention described in claim 5, in addition to the invention described in any one of claims 1 to 4, there is an advantage that the coating film is easily cured at room temperature, and there is little residual diluent in the coating film. is there.

According to the sixth aspect of the present invention, there is an advantage that the suction and unevenness of the object to be coated can be alleviated and a uniform coating film can be easily formed on the object to be coated.

Hereinafter, embodiments embodying the present invention will be described.
It is essential that the organic polysilazane coating material of the present invention contains organic polysilazane and silicone oil.

  By mixing silicone oil with organic polysilazane, uniform coating formation with organic polysilazane is facilitated. In addition, due to the water repellency and oil repellency characteristics of the organic polysilazane coating film, the coating film formed from the organic polysilazane paint is excellent in antifouling property, decontamination property and the like.

The organic polysilazane is obtained by polymerizing an organic silazane having a hydrocarbon added to the side chain, and is represented by a chemical formula as shown in Chemical Formula 1, for example.

Here, the side chains R1 to R2 are an alkyl group, an alkoxy group, or a hydrogen atom. In addition, when all of R1 and R2 are hydrogen atoms, it becomes inorganic polysilazane. However, since inorganic polysilazane is hydrophilic and easily contaminated with oil or the like, organic polysilazane is used in the paint of the present invention. To do.

  Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a vinyl group, a phenyl group, and a long chain alkyl group.

  Moreover, you may use what copolymerized the silazane from which a side chain differs. For example, an organic polysilazane represented by Chemical Formula 1 and having a different side chain R1 to R2 is copolymerized. As such a thing, there exists a thing represented by Chemical formula of Chemical formula 2, for example. In Chemical Formula 2, side chains R1 and R2 and side chains R3 and R4 are not the same.

In Chemical Formula 2, when all of the side chains R1 to R4 are hydrogen atoms, they are inorganic polysilazanes, and the others are organic polysilazanes. Among organic polysilazanes, the use of an organic polysilazane in which any one of R1 and R2 and any of R3 to 4 is other than a hydrogen atom makes it easier to obtain a paint having excellent antifouling properties and decontamination properties.
Chemical formula 2 is represented by chemical formula 1 and is a combination of two types of silazanes having different side chains R1 to R2, but may be a combination of two or more types of silazanes.

When the organic polysilazane is hydrolyzed, nitrogen atoms are removed to generate ammonia gas and are replaced with oxygen atoms. Si—O forms a three-dimensional continuous bond to form an organic polysilazane coating film.

The side chains R <b> 1 to R <b> 2 of the organic polysilazane can be arbitrarily set according to the physical properties imparted to the coating film formed by the organic polysilazane paint.

For example, when imparting flexibility to the coating film, it is preferable to use an alkyl group having 4 or more carbon atoms such as a butyl group or a phenyl group, and when imparting water repellency to the coating film, a propyl group, a butyl group, It is preferable to use a long-chain alkyl group or the like.

In addition, when imparting oil repellency to the coating film, it is preferable to use an alkyl group having 2 or less carbon atoms such as a methyl group or an ethyl group, and a methyl group or an ethyl group is imparted to both side chains R1 and R2. It is preferable. In particular, it is preferable to use one or both of methylpolysilazane and dimethylpolysilazane, and it is most preferable to use dimethylpolysilazane.

In addition, the bonding reaction of organic polysilazane is facilitated during baking, and an alkyl group having a double bond such as a vinyl group or an alkoxy group such as a methoxy group or an ethoxy group is used in order to quickly form a uniform coating film. It is preferable.

The organic polysilazane can be used in various structures such as linear, branched and cyclic.

In the organic polysilazane coating, it is preferable that an organic polysilazane having a cyclic structure (hereinafter referred to as a cyclic body) is contained in the total amount of the organic polysilazane, and the content is preferably 0.1 to 30% by mass. More preferably, it is 0.3-8 mass%, Most preferably, it is 0.5-5 mass%. When it is in this range, a dense coating film is formed, so that the anti-contamination property and the decontamination property are excellent. In addition, because the cyclic body has a buffering action in the coating film, it suppresses main chain breakage, so it has excellent heat resistance, and even at high temperatures, the coating film does not cause abnormalities such as cracks, preventing contamination and removing contamination. The ability to demonstrate. When the content of the annular body is less than 0.1% by mass, the heat resistance effect is not sufficient. Conversely, when it exceeds 30% by mass, it is difficult for other organic polysilazanes to penetrate into the annular body, so that the three-dimensional structure of Si—O tends to be sparse and difficult to form a dense coating film. In particular, when the molecular weight of the side chain alkyl group is large, the three-dimensional structure of Si—O tends to be sparse.

As the organic polysilazane, one produced by a known production method can be used. As a known manufacturing method, for example, a manufacturing method described in JP-T-2006-515641 can be cited.

The organic polysilazane is preferably contained in an amount of 2 to 65 parts by weight, more preferably 5 to 50 parts by weight, and more preferably 10 to 30 parts by weight with respect to 100 parts by weight of a volatile component contained in the organic polysilazane coating. Part content is particularly preferred. When it is within this range, a dense and uniform coating film can be formed. When the mixing ratio of the organic polysilazane with respect to 100 parts by mass of the silicone oil is less than 2 parts by mass, the formed coating film is difficult to be dense and forms a uniform coating film with sufficient Si-O formation. Therefore, there is a risk that the anti-staining property and decontamination property of the coating film may not be sufficiently exhibited. On the other hand, when it exceeds 65 parts by mass, there is a risk that problems such as cracks may occur in the process of drying or baking the organic polysilazane coating.

The silicone oil is a polymer having a linear structure composed of a siloxane bond, for adjusting the viscosity of the organic polysilazane, and for forming a uniform coating film by organic polysilazane by assisting the formation of the coating film during baking or drying. Used for. Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, monoamine-modified silicone oil, diamine-modified silicone oil, special amino-modified silicone oil, epoxy-modified silicone oil, alicyclic epoxy-modified silicone oil, and carbinol-modified silicone oil. , Mercapto modified silicone oil, carboxyl modified silicone oil, hydrogen modified silicone oil, amino / polyether modified silicone oil, epoxy / polyether modified silicone oil, epoxy / aralkyl modified silicone oil, polyether modified silicone oil, aralkyl modified silicone oil , Fluoroalkyl-modified silicone oil, long-chain alkyl-modified silicone oil, higher fatty acid ester Modified silicone oil, higher fatty acid amide modified silicone oil, polyether / long chain alkyl / aralkyl modified silicone oil, long chain alkyl / aralkyl modified silicone oil, phenyl modified silicone oil, phenol modified silicone oil, amino modified silicone oil, side chain Examples include amino and both-end methoxy-modified silicone oils.

Of the silicone oils, dimethyl silicone oil is particularly preferably used for the organic polysilazane coating. By using dimethyl silicone oil, the drying property of the organic polysilazane coating can be improved. Dimethyl silicone oil is a silicone oil in which all side chains and terminals of polysiloxane are methyl groups, as shown in Chemical formula 3.

The kinematic viscosity at 25 ° C. of the silicone oil measured in accordance with JIS K2238; 2000 (hereinafter, kinematic viscosity refers to the kinematic viscosity measured under these conditions) is preferably 0.2 to 10 mm ² / s. More preferably, it is 0.4-5 mm < ² > / s, Most preferably, it is 0.6-2 mm < ² > / s. When the kinematic viscosity of the silicone oil is 0.2 to 10 mm ² / s, the organic polysilazane paint can be easily applied to the surface to be coated, and the paint applied to the object can be easily dried at room temperature. There is little residual diluent.

Silicone oils having a kinematic viscosity exceeding 10 mm ² / s have a large molecular weight and slow volatilization, so that the silicone oil may remain in the coating film and inhibit the formation of a uniform coating film. In addition, those having a high kinematic viscosity are not easily adapted to an object to be coated, so that the film thickness is likely to be uneven, and a smooth and uniform film thickness may not be easily formed. Conversely, silicone oil with a kinematic viscosity of less than 0.2 mm ² / s has a low molecular weight and is too fast to volatilize. Therefore, when coating, the silicone oil volatilizes during coating, and the film thickness is smooth and uniform. There is a possibility that a simple coating film cannot be easily formed.
If the film thickness after coating is not uniform, problems such as cracking during drying or firing are likely to occur. In addition, when unevenness occurs in the film thickness, there is a difference in the volatilization rate of the silicone oil between the thick part and the thin part, and the thick part tends to be sparse so that a dense and uniform coating can be achieved. There is a possibility that the film cannot be formed, and the anti-contamination property and the decontamination property of the coating film are not sufficiently exhibited.

  Among silicone oils having a kinematic viscosity in the above range, the surface tension at 25 ° C. measured according to the surface tension test method of JIS K 2241; 2000 is 13 to 23 mN / m, more preferably 15 to 22 mN / m. By using m, the organic polysilazane paint is more easily adapted to the surface to be coated, and a uniform coating film is easily formed. When the surface tension is less than 13 mN / m, the coating film becomes uniform, but it is difficult to ensure the thickness of the coating film.

  The silicone oil is preferably contained in an amount of 60% by mass or more, and particularly preferably 80% by mass or more, in a volatile component contained in the organic polysilazane paint. When a large amount of silicone oil is contained in the volatile component, it is easy to form a uniform coating film. If the content of silicone oil in the volatile component is too small, there is a risk that problems such as insufficient formation of Si—O bonds due to hydrolysis of organic polysilazane and formation of a dense coating film may occur. Examples of volatile components other than silicone oil include diluents and volatile additives.

As long as the effects of the present invention are not impaired in the organic polysilazane paint, extender pigments such as talc, clay and calcium carbonate used in general paints, white pigments such as titanium oxide, iron oxide, carbon black, phthalocyanine blue and the like Coloring pigments, thickeners, dispersants, wetting agents, antifoaming agents, additives such as fibers, and diluents other than silicone oil may be included. As the diluent, those having good compatibility with silicone oil, such as aromatic solvents such as toluene and xylene, are used.

  Among the additives, it is preferable to add a substance having a catalytic action (hereinafter also simply referred to as a catalyst) that promotes the organic polysilazane binding reaction.

Examples of the catalyst include 1-methylpiperazine, 1-methylpiperidine, 4,4′-trimethylenedipiperidine, 4,4′-trimethylenebis (1-methylpiperidine), diazabicyclo- [2,2,2 ] Octane, cis-2,6-dimethylpiperazine, 4- (4-methylpiperidine) pyridine, pyridine, dipyridine, α-picoline, β-picoline, γ-picoline, piperidine, lutidine, pyrimidine, pyridazine, 4,4 ′ -N-heterocyclic compounds such as trimethylenedipyridine, 2- (methylamino) pyridine, pyrazine, quinoline, quinoxaline, triazine, pyrrole, 3-pyrroline, imidazole, triazole, tetrazole, 1-methylpyrrolidine; methylamine, dimethyl Amine, trimethylamine, ethylamine, diethyl Amine, triethylamine, propylamine, dipropylamine, tripropylamine, butylamine, dibutylamine, tributylamine, pentylamine, dipentylamine, tripentylamine, hexylamine, dihexylamine, trihexylamine, heptylamine, diheptylamine, Amines such as octylamine, dioctylamine, trioctylamine, phenylamine, diphenylamine, triphenylamine; DBU (1,8-diazabicyclo [5,4,0] 7-undecene), DBN (1,5-diazabicyclo) [4,3,0] 5-nonene), 1,5,9-triazacyclododecane, 1,4,7-triazacyclononane and the like. Organic acids, inorganic acids, metal carboxylates, acetylacetona complexes, and metal fine particles are also preferable catalysts. Organic acids include acetic acid, propionic acid, butyric acid, valeric acid, maleic acid, stearic acid, and inorganic acids include hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrogen peroxide, chloric acid, hypochlorous acid, etc. Is mentioned. The metal carboxylate has the formula: (RCOO) nM [wherein R represents an aliphatic group or an alicyclic group and represents one having 1 to 22 carbon atoms, and M represents Ni, Ti, Pt, Rh, Co. Represents at least one metal selected from the group consisting of Fe, Ru, Os, Pd, Ir, and Al, and n is the valence of M. It is a compound represented by. The metal carboxylate may be an anhydride or a hydrate. An acetylacetona complex is a complex in which acetylacetonate (acac ⁻ ), which is an anion generated by acid dissociation from acetylacetone (2,4-pentadione), is coordinated to a metal atom. ₃ COCHCOCH ₃ ) nM [wherein M represents an n-valent metal. ] Is represented. Suitable metals M include, for example, nickel, platinum, palladium, aluminum, rhodium and the like. As the metal fine particles, Au, Ag, Pd, and Ni are preferable, and Ag is particularly preferable. In order to efficiently obtain the catalytic effect of the metal fine particles, the particle size of the metal fine particles is preferably 0.5 μm or less, more preferably 0.1 μm or less, and even more preferably 0.05 μm or less. In addition to these, organic metal compounds such as peroxide, metal chloride, ferrocene, zirconocene and the like can also be used. These catalysts are blended in an amount of 0.01 to 30 parts by mass, preferably 0.1 to 10 parts by mass, particularly preferably 0.5 to 7 parts by mass with respect to 100 parts by mass of the organic polysilazane.

Specific embodiments of the organic polysilazane paint configured as described above are shown below. However, the present invention is not limited to the following embodiments.

<First embodiment>
The organic polysilazane paint can be used, for example, as a coating agent for a glass top plate of an IH cooking heater that is an electric cooking appliance.

The glass top plate is required to have performances such as anti-contamination properties and decontamination properties because oil stains and water stains adhere to the glass top plate. By coating the glass top plate with the organic polysilazane paint of the present invention and coating the glass top plate, the glass top plate has excellent anti-contamination and decontamination properties, and easily removes oil stains and water stains. be able to.

In addition, since the coating film made of organic polysilazane has heat resistance, the coating does not deteriorate even when the glass top plate becomes hot, and the oil adheres to it because of high temperature oil adhesion or the glass top plate becoming hot. The coating effect can be obtained against oil stains.

  The organic polysilazane paint to be applied to the glass top plate may have the above composition. As a specific example, the following composition can be used.

Composition example of organic polysilazane paint: 100 parts by mass of dimethylpolysilazane (straight chain) as organic polysilazane forming a coating film, 310 parts by mass of dimethyl silicone (kinematic viscosity 1.5 mm ² / s), 2 parts by mass of dimethylamine as a catalyst .

The film formation process of the organic polysilazane paint is as follows.
First, an organic polysilazane paint is applied to an object to be coated. The painting method and painting equipment at that time may be those generally used for painting paints. For example, painting is performed using a painting equipment or painting machine such as a roller, brush, air spray, airless spray, dipping, or flow coater. do it.

The coating amount of the organic polysilazane coating is preferably set so that the thickness of the coating film after curing with the organic polysilazane coating is 1 to 80 μm, and more preferably set so that the thickness of the coating film is 2 to 50 μm. It is particularly preferable to set the thickness of the coating film to be 5 to 30 μm.
If the thickness of the coating film made of the organic polysilazane coating is too thin, there is a risk that the anti-contamination property and the decontamination property due to the coating film may not be sufficiently exhibited. On the other hand, if the thickness of the coating film is too thick, defects such as cracks may occur in the coating drying or baking process, and a healthy coating film may not be formed, or the coating film tends to be sparse, and the coating film is dense. May not be formed, and there is a risk that the anti-staining property and decontamination property of the coating film may not be sufficiently exhibited.

After the organic polysilazane paint is applied to the object to be coated, drying is performed at room temperature (general room temperature, specifically, a temperature of about 5 to 40 ° C.). After forming the coating film at room temperature, baking is performed at 50 ° C to 500 ° C. Thereafter, curing is performed under high temperature and high humidity conditions (preferably, a temperature of 40 to 80 ° C. and a humidity of 50% or more). By providing the baking process and the curing process under high-temperature and high-humidity conditions, the curing reaction of the organic polysilazane can be promoted, and a dense and uniform coating film made of the organic polysilazane paint can be formed more quickly.

The baking temperature is preferably 50 to 500 ° C, more preferably 60 to 400 ° C, and most preferably 80 to 300 ° C. When it exists in this range, a uniform coating film can be formed rapidly. If the baking temperature is too low, the curing reaction of the organic polysilazane cannot be sufficiently accelerated. Conversely, if the baking temperature is too high, problems such as cracking and peeling of the coating film due to the difference in coefficient of thermal expansion with the object to be coated tend to occur.

In addition, it is desirable to perform the baking in two stages. For example, in the first stage, baking is performed at 50 ° C. to 100 ° C., and then baking is performed at 100 ° C. to 500 ° C. By baking in two stages, problems such as cracks that tend to occur during baking can be reduced.

<Second embodiment>
The organic polysilazane paint of the present invention can be used as a coating agent for the inner wall of a tunnel. The tunnel inner wall is easily contaminated by dust such as dust and exhaust gas. In addition, it may be stained by graffiti by lacquer spray. By applying a polysilazane-containing paint on the inner wall of the tunnel to make the wall surface anti-contaminant and decontaminating, it becomes difficult for those stains to adhere to the wall surface, and the stain attached to the wall surface can be easily removed. .

  As the organic polysilazane paint for coating the inner wall of the tunnel, those having the above-described composition may be used. As a specific example, the following composition can be used.

Composition example of organic polysilazane coating: 100 parts by mass of methyl polysilazane (straight chain) as organic polysilazane forming the coating film, vinyl polysilazane as organic polysilazane (60% by mass of straight chain, 40% by mass of cyclic product) (n = 20 to 30) 20 parts by mass, 350 parts by mass of dimethyl silicone oil (kinematic viscosity 0.65 mm ² / s).

The film formation process of the organic polysilazane paint is as follows.
First, a water-based acrylic resin paint as an undercoat paint is applied to a concrete tunnel inner wall with a wool roller at a coating amount of 100 g / m ² . After the aqueous acrylic resin paint is dried, the organic polysilazane paint is applied with a wool roller at a coating amount of 50 g / m ² .

As the undercoat paint, those having good adhesion to the concrete surface and good adhesion to the organic polysilazane paint can be appropriately used. The composition is not limited to acrylic, and commonly used paints can be used, which may be aqueous or oily.

By using the undercoat paint, it is possible to alleviate the suction and unevenness of the object to be coated, and to easily form a coating film having a uniform thickness on the object to be coated. For example, even if the object to be coated is porous like concrete and the suction is large, the amount of suction can be adjusted with the undercoat paint, so the organic polysilazane paint to be painted after that is sucked into the concrete, Since a coating film having a sufficient film thickness cannot be formed on the concrete surface, it is possible to suppress problems such as that the coating film does not exhibit sufficient anti-staining and decontamination properties.

The undercoat paint is preferably colored. By coloring the undercoat paint, the surface to be coated can be freely colored.

The coating hardness of the undercoat paint is preferably HB or higher, more preferably H or higher, and most preferably 2H or higher in terms of scratch hardness (pencil method) defined in JIS K5600; When in this range, cracking of the organic polysilazane coating film can be suppressed when the organic polysilazane coating film is formed on the coating film of the undercoat paint. When the scratch hardness (pencil method) of the undercoat paint film is less than HB, the organic polysilazane paint film formed on the undercoat paint film may be cracked.

Although the coating method to the said tunnel inner wall is not specifically limited, The coating by a roller is preferable. The organic polysilazane coating film coated on the inner wall of the tunnel is dried at room temperature. In the case of a tunnel inner wall, it is difficult to perform a baking process such as the glass top plate shown in the first embodiment and a curing process under a high temperature and high humidity condition. Performance such as removability is obtained. For example, when cured at room temperature for about 2 weeks, the curing reaction of the coating film proceeds sufficiently, and performances such as antifouling properties and decontamination properties are exhibited.

The present embodiment can exhibit the following effects.
-By applying the organic polysilazane coating on the surface of the object to be coated to form a coating film of the organic polysilazane, it is possible to improve the anti-contamination property and the decontamination property.
-By diluting the organic polysilazane with the silicone oil, it is possible to form a uniform coating film with the organic polysilazane by assisting in adjusting the viscosity and forming a coating film during baking or drying.
-Since the dimethyl silicone oil has a kinematic viscosity of 0.2 to 10 mm ² / s, a smooth and uniform coating film can be easily formed.

  In addition, the said embodiment of this invention can also be changed and comprised as follows.

In the above embodiment, the organic polysilazane paint is used as a coating agent for electric cooking utensils and a coating agent for the inner wall of the tunnel, but the object to be painted can be set arbitrarily. For example, water-related products such as bathtubs, kitchen sinks, washstands, etc., building materials made of various materials such as porcelain tiles, natural stones, glass, plastics, ceramics, metals, concrete, mortar, bricks, and the like.
Of these, by applying an organic polysilazane paint to the surface of the ceramic before glazing, a glassy film can be formed on the surface of the ceramic without using glaze, protecting the ceramic and preventing pollution. It is possible to impart decontamination property.

  In the second embodiment, a coating film made of organic polysilazane paint is provided on the tunnel inner wall. However, organic polysilazane paint is applied to places where dirt is likely to adhere or where there is a risk of graffiti, such as underpass passages and outer walls of buildings. You may provide the coating film by.

-In said 2nd embodiment, although the coating film by organic polysilazane coating was provided in the tunnel inner wall, you may provide the coating film by organic polysilazane coating on floor surfaces, such as a factory floor.
When used on the floor, the anti-contamination and decontamination properties are exhibited not only against dirt caused by dust, but also against dirt caused by forklift slip marks and shoe sole rubber.

Next, technical ideas other than the invention described in the claims ascertained from the embodiment will be described together with their effects.
(1) An organic polysilazane paint according to any one of claims 1 to 5 is coated on the surface of the ceramic before glazing. When comprised in this way, a glassy film can be formed in the ceramic surface, without using a glaze.

  Examples of the present invention and comparative examples are shown below.

The organic polysilazane used in this example is as follows. In addition, all the content rates of the organic polysilazane of 1-5 are 100 mass%.
1: Methyl polysilazane (straight chain) n = 10-30
2: Dimethylpolysilazane (straight chain) n = 50 to 150
3: Dimethylpolysilazane (linear 80% by mass, cyclic 20% by mass) n = 40-100
4: Butylpolysilazane (linear) n = 20-60
5: Organic polysilazane (straight chain) n = 5 to 25 shown in Chemical formula 4

The following silicone oil was used.
A: Dimethyl silicone oil Kinematic viscosity: 0.65 mm ² / s
B: Dimethyl silicone oil Kinematic viscosity: 1.5 mm ² / s
C: Dimethyl silicone oil Kinematic viscosity: 5 mm ² / s
D: Dimethyl silicone oil Kinematic viscosity: 10 mm ² / s
E: Phenol-modified silicone oil Kinematic viscosity: 100 mm ² / s

The following organic solvents were used as diluents other than silicone oil.
F: Toluene G: Xylene H: Butyl acetate

The compositions of the organic polysilazane paints of Examples 1-21 and Comparative Examples 1-4 are shown in Tables 1-5. In addition, the composition shown to a table | surface shows the compounding quantity of each raw material by a mass part.

In Tables 1 to 5, the thickness of each organic polysilazane paint film formed by the following procedure and the evaluation results of the film formability, contamination prevention property, contamination removal property, and heat resistance of the coating film are also described. To do.

(Formation of coating film)
The organic polysilazane paints of Examples 1 to 21 and Comparative Examples 1 to 4 were spray-coated on a glass plate having a length of 100 mm, a width of 100 mm, and a thickness of 5.0 mm. After painting, curing at 25 ° C and 60% humidity for 3 hours and drying, followed by baking at 100 ° C for 1 hour, and further baking at 150 ° C for 1 hour, followed by 12 hours at 25 ° C and 60% humidity Curing was performed to prepare a test body (there was a baking process; hereinafter referred to as test body α).
Separately from the above, each organic polysilazane paint is spray-coated on a glass plate having a length of 100 mm, a width of 100 mm and a thickness of 5.0 mm without baking, and then cured at 25 ° C. and a humidity of 60% for 2 weeks. Thus, a dried test body (no baking step; hereinafter referred to as test body β) was produced.

(Method for evaluating film formability)
The specimens after baking and curing were observed with a microscope (500 times magnification) to confirm the presence or absence of cracks in the coating film, and evaluated as follows.
○: No crack ×: There is a crack

Further, the degree of acceleration of the binding reaction of the coating film was evaluated using Fourier transform infrared spectroscopy (FT-IR). Focusing on the fact that organic polysilazane dislodges nitrogen atoms by hydrolysis to generate ammonia gas and replaces it with oxygen atoms, and finally the H—N bond disappears, and the following evaluation was made based on the measurement results of FT-IR. .
○: H-N bond peak not observed x: H-N bond peak observed

(Evaluation method for pollution prevention)
The test specimen β was placed horizontally, 5 ml of machine oil was dropped on it and allowed to stand for 1 hour, and then the machine oil was lightly wiped with a dry cloth, and the state of the test specimen was observed and evaluated as follows.
A: Not as dirty as the test specimen α of Example 1 ○: The same degree of dirt as the test specimen α of Example 1 is seen Δ: Slightly noticeable dirt compared to the test specimen α of Example 1 ×: Dirty compared to the specimen α of Example 1

(Evaluation method for decontamination)
Place the test body β horizontally, hang 5 ml of machine oil on it, and heat at 200 ° C. for 30 minutes to cause the machine oil to stick to the test body. Thereafter, the test body was washed with a neutral detergent, water and a sponge, the state of the test body was observed, and evaluated as follows.
A: Not as dirty as the test specimen α of Example 1 ○: The same degree of dirt as the test specimen α of Example 1 is seen Δ: Slightly noticeable dirt compared to the test specimen α of Example 1 ×: Dirty compared to the specimen α of Example 1

(Method for evaluating heat resistance)
Four specimens β were prepared, and each specimen was heated in an electric furnace at 100 ° C., 200 ° C., 300 ° C., and 400 ° C. for 1 hour, and then the state of the coating film was observed. It was evaluated as follows.
○: No abnormality ×: Cracking occurred

Claims (6)

An organic polysilazane paint comprising organic polysilazane and silicone oil. The organic polysilazane paint according to claim 1, wherein the silicone oil includes dimethyl silicone oil. The organic polysilazane paint according to claim 1 or 2, wherein the organic polysilazane includes one of methylpolysilazane and dimethylpolysilazane, or a mixture of both. The organic polysilazane paint according to any one of claims 1 to 3, wherein the organic polysilazane contains a cyclic body in an amount of 0.1 to 30% by mass. The organic polysilazane paint according to claim 1, wherein the silicone oil has a kinematic viscosity at 25 ° C. of 0.2 to 10 mm ² / s. An organic polysilazane paint coating method, comprising: applying an organic polysilazane paint according to any one of claims 1 to 5 after applying an undercoat paint to an object to be coated.