JPH06306329A - Composition and method for coating - Google Patents

Abstract

PURPOSE:To obtain a coating compsn. which gives, by low-temp. baking, a dense coating film excellent in resistances to heat, abrasion, and corrosion and in adhesion to a substrate by incorporating a specific acetylacetonate complex adduct of polysilazane into the compsn. CONSTITUTION:A coating compsn. contains an acetylacetonate complex adduct of polysilazane which has a number-average mol.wt. of about 200-500,000 and is obtd. by reacting polysilazane having a number-average mol.wt. of 100-50,000 and a backbone consisting of structural units of the formula wherein R<1>, R<2>, and R<3> are each H, (cyclo)alkyl, alkenyl, aryl, a group other than the foregoing groups and attached to Si through C, alkylsilyl, alkylamino, or alkoxy provided at least one of them is H with an acetylacetonate complex of the formula: (CH3COCH2COCH3)nM wherin M is an n-valent metal in a wt. ratio of the complex to polysilazane of 0.000001-2.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a coating composition containing a modified polysilazane as an essential component and capable of forming a coating film excellent in heat resistance, abrasion resistance and corrosion resistance, and a coating method using the same.

[0002]

2. Description of the Related Art Organic paints are not sufficient for obtaining high heat resistance, wear resistance and corrosion resistance, and ceramic coatings are used. Conventionally, as a method of forming a ceramic coating, PVD (sputtering method, etc.),
Known are CVD, sol-gel method, polytitanocarbosilane-based paint, poly (dicyl) silazane-based paint, polysilazane-based paint, polymetallosilazane-based paint, and the like.

[0003]

The above-mentioned ceramics-based coating methods are known, but all have problems. That is, the PVD and CVD methods are expensive. In the sol-gel method, the required firing temperature is as high as 500 ° C or higher. Low-temperature baking (4
The surface strength at 00 ° C. or lower) is insufficient. Those using a poly (disyl) silazane-based polymer are difficult to apply and cracks occur. Polysilazane and polymetallosilazane coatings can be fired at 200 to 500 ° C, but firing at less than 300 ° C does not necessarily give good film quality.

Therefore, the present invention solves the problems in the prior art as described above, heat resistance by low temperature (50 ° C. to 350 ° C.) firing, or by holding at a temperature of less than 50 ° C. without firing, To provide a coating composition having excellent wear resistance and corrosion resistance, which gives a dense coating film without cracks, and a construction method therefor, in particular, electronic components, plastics, etc. The purpose is to enable coating on.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a coating film of the adduct is formed by adding an acetylacetonato complex containing a metal to polysilazane. It has been found that the curing reaction is promoted when firing in air, and a good coating is formed at a firing temperature lower than before.

Thus, according to the present invention, the general formula (I):

[0007]

[Chemical 2]

(However, R ¹ , R ² and R ³ are each independently a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or a group other than these groups in which the group directly bonded to silicon is carbon. , An alkylsilyl group, an alkylamino group, and an alkoxy group, provided that R ¹ ,
At least one of R ² and R ³ is a hydrogen atom. )
A polysilazane having a main skeleton composed of a unit represented by the following formula and a number average molecular weight of 100 to 50,000, and a general formula (CH ₃ COC
HCOCH ₃ ) _n M [wherein M represents an n-valent metal]
The acetylacetonato complex / polysilazane weight ratio, which is obtained by reacting the acetylacetonato complex represented by, is in the range of 0.000001 to 2 and the number average molecular weight is about 2.
Provided is a coating composition containing at least 100,000 to 500,000 acetylacetonato complex-added polysilazane.

The acetylacetonato complex-added polysilazane used in the present invention has a number average molecular weight of 200 to 500,000, preferably 500 to 10,000. The method for producing the acetylacetonato complex-added polysilazane used in the present invention comprises reacting the polysilazane and the acetylacetonato complex with or without a solvent and in an atmosphere inert to the reaction.

The polysilazane to be used may be any polysilazane having at least a Si--H bond or an N--H bond in the molecule. Not only polysilazane alone, but also a copolymer of polysilazane and another polymer or polysilazane and other It can also be used as a mixture with the compound of. The polysilazanes to be used include those having a chain structure, a cyclic structure, or a crosslinked structure, or those having a plurality of these structures simultaneously in the molecule, and these can be used alone or in a mixture.

Typical examples of the polysilazane to be used are as follows, but are not limited thereto. The ^one having hydrogen atoms in R ¹ , R ² and R ³ in the general formula (I) is perhydropolysilazane, and its production method is described in, for example, JP-A-60-145903 and D. Seyf.
erth et al Communication of Am.Cer.Soc., C-13, January
1983. Has been reported to. What is obtained by these methods is a mixture of polymers having various structures, but basically contains a chain portion and a cyclic portion in the molecule,

[0012]

[Chemical 3]

It can be represented by the chemical formula: An example of the structure of perhydropolysilazane is as follows.

[0014]

[Chemical 4]

In the general formula (I), R ¹ and R ² are hydrogen atoms,
A method for producing polysilazane having a methyl group in R ³ is described in D.
Seyferth et al. Polym.Prepr., Am.Chem.Soc., Div.Polym.Che
m ,. 25 , 10 (1984). The polysilazane obtained by this method has a repeating unit of −
(SiH ₂ NCH ₃₎ - is a chain polymer and a cyclic polymer, either no cross-linked structure.

In the general formula (I), R ¹ and R ³ are hydrogen atoms,
A method for producing a polyorgano (hydro) silazane having an organic group in R ² is described in D. Seyferth et al., Polym.Prepr., Am.Chem.Soc.,
Div. Polym. Chem., 25 , 10 (1984), JP-A-61.
-89230. Polysilazanes obtained by these methods include-(R ² SiHNH)
-Having a cyclic structure having a degree of polymerization of 3 to 5 as a repeating unit, or (R ³ SiHNH) _x [(R ² S
iH) _1.5 N] _1−X (0.4 <x <1) has a chain structure and a cyclic structure at the same time in the molecule.

In the general formula (I), polysilazane having a hydrogen atom at R ¹ and an organic group at R ² and R ³ , and R ¹ and R ²
An organic group for R ³ and a hydrogen atom for R ³ is — (R ¹ R ²
SiNR ³ ) -is a repeating unit and the degree of polymerization is mainly 3
It has a cyclic structure of ~ 5. Among the polysilazanes used next, typical examples other than those of the general formula (I) will be given.

Among the polyorgano (hydro) silazanes are D. Seyferth et al. Communication of Am. Cer. Soc., C-1.
32, July 1984. There are also those having a cross-linked structure in the molecule as reported in. An example is as follows.

[0019]

[Chemical 5]

Further, polysilazane (R having a crosslinked structure obtained by ammonia decomposition of R ¹ SiX ₃ (X: halogen) as reported in JP-A-49-69717 (R
¹ Si (NH) _x ), or R ¹ SiX ₃ and R ² ₂ S
Polysilazane having the following structure obtained by co-ammonia decomposition of iX ₂ can also be used as a starting material.

[0021]

[Chemical 6]

The polysilazane to be used has a main skeleton consisting of the unit represented by the general formula (I) as described above, but the unit represented by the general formula (I) may be cyclized as is apparent from the above. In that case, the cyclic portion serves as a terminal group, and when such cyclization is not carried out, the terminal of the main skeleton can be a group similar to R ¹ , R ² and R ³ or hydrogen.

The molecular weight of the polysilazane to be used is not particularly limited and any available polysilazane can be used, but R ¹ , R ² and R ³ in the formula (I) can be used in view of reactivity with the acetylacetonato complex. Is preferably a group having a small steric hindrance. That is, R ¹ , R ² and R ³ are hydrogen atoms and C
_{1 to} C ₅ alkyl groups are preferable, and a hydrogen atom and C ₁ to
More preferred is a C ₂ alkyl group. Acetylacetonato complex used is acetylacetone (2,4-pentanedione) Yin caused by acid dissociation from ion acac ^- are complex coordinated to a metal atom, typically formula (CH ₃ C
OCHCOCH ₃₎ in _n M [wherein, M represents a metal ion valence n. ] Is represented. Examples of suitable metal M include nickel, platinum, palladium, aluminum, rhodium, and the like. For example, when nickel is used as the metal M, it has the following structure.

[0024]

[Chemical 7]

The mixing ratio of polysilazane and acetylacetonato complex is such that the acetylacetonato complex / polysilazane weight ratio is 0.000001 to 2, preferably 0.001 to 1, and more preferably 0. Add from 0.01 to 0.5. If the amount of the acetylacetonato complex added is increased beyond this range, the molecular weight of the polysilazane increases too much to cause gelation, and if it is too low, a sufficient effect cannot be obtained.

Although the reaction can be carried out without solvent,
Compared to the case of using an organic solvent, it is generally preferable to use an organic solvent because it is difficult to control the reaction and a gelled substance may be generated. As the solvent, aromatic hydrocarbons, aliphatic hydrocarbons, hydrocarbon solvents of alicyclic hydrocarbons, halogenated hydrocarbons, aliphatic ethers, alicyclic ethers, and aromatic amines can be used. Preferred solvents include, for example, benzene, toluene, xylene, methylene chloride, chloroform, n-hexane, ethyl ether, tetrahydrofuran, pyridine, methylpyridine and the like, and particularly preferred solvents include xylene, pyridine, methylpyridine and the like. Also, an atmosphere inert to the reaction,
For example, the reaction is preferably carried out in an atmosphere of nitrogen, argon or the like, but it is also possible in an oxidizing atmosphere such as air.

The reaction temperature can be varied over a wide range. For example, when an organic solvent is used, it may be heated to a temperature below the boiling point of the organic solvent, but in order to obtain a solid having a high number average molecular weight. Alternatively, the reaction can be carried out by subsequently heating the organic solvent to a boiling point or higher to distill off the organic solvent. Generally, the reaction temperature is preferably 150 ° C. or lower.

The reaction time is not particularly important, but is usually 1
It is about 50 hours. It is generally preferable to carry out the reaction at around normal pressure. In the present invention, in order to prepare a coating composition using the acetylacetonato complex-added polysilazane, usually, the acetylacetonato complex-added polysilazane may be dissolved in a solvent.

Examples of the solvent include aliphatic hydrocarbons, alicyclic hydrocarbons, hydrocarbon solvents of aromatic hydrocarbons, halogenated hydrocarbons such as halogenated methane, halogenated ethane and halogenated benzene, aliphatic ethers, and fats. Ethers such as cyclic ethers can be used. Preferred solvents are halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, bromoform, ethylene chloride, ethylidene chloride, trichloroethane and tetrachloroethane, ethyl ether,
Ethers such as isopropyl ether, ethylbutyl ether, butyl ether, 1,2-dioxyethane, dioxane, dimethyldioxane, tetrahydrofuran, tetrahydropyran, pentanehexane, isohexane, methylpentane, heptane, isoheptane, octane, isooctane, cyclopentane, methylcyclopentane And hydrocarbons such as cyclohexane, methylcyclohexane, benzene, toluene, xylene and ethylbenzene.

When these solvents are used, two or more kinds of solvents may be mixed in order to adjust the solubility of the acetylacetonato complex-added polysilazane and the evaporation rate of the solvent. The amount (ratio) of the solvent used is selected so as to improve the workability depending on the coating method adopted, and it depends on the average molecular weight, the molecular weight distribution, and the structure of the acetylacetonato complex-added polysilazane. It is possible to mix up to about 10% by weight, preferably 10 to 50% by weight.

The solvent concentration varies depending on the average molecular weight, the molecular weight distribution and the structure of the acetylacetonato complex-added polysilazane, but good results are usually obtained in the range of 0 to 90% by weight. Further, in the present invention, a suitable filler may be added if necessary. Examples of the filler include fine powders of oxide-based inorganic materials such as silica, alumina, zirconia, and mica, or non-oxide-based inorganic materials such as silicon carbide and silicon nitride. Depending on the application, it is also possible to add metal powders such as aluminum, zinc and copper. More specifically, examples of fillers include silica-based materials such as silica sand, quartz, novaculite, and diatomaceous earth: synthetic amorphous silica: kaolinite, mica, talc, wollastonite, asbestos, calcium silicate, aluminum silicate. Silicates such as: glass powder, glass spheres, hollow glass spheres, glass flakes, glass spheres such as foam glass spheres: boron nitride, boron carbide, aluminum nitride, aluminum carbide, silicon nitride, silicon carbide, titanium boride, nitride Non-oxide inorganic substances such as titanium and titanium carbide: calcium carbonate: zinc oxide, alumina, magnesia, titanium oxide, beryllium oxide and other metal oxides: barium sulfate, molybdenum disulfide,
Tungsten disulfide, carbon fluoride, and other inorganic substances: metal powders such as aluminum, bronze, lead, stainless steel, zinc: carbon black, coke, graphite, pyrolytic carbon, carbon bodies such as hollow carbon spheres, and the like.

These fillers have various shapes such as needle-like shape (including whiskers), granular shape, and scale-like shape, either alone or in 2 pieces.
A mixture of two or more species can be used. Further, it is desirable that the particle size of these fillers is smaller than the film thickness that can be applied at one time. The amount of the filler added is in the range of 0.05 parts by weight to 10 parts by weight with respect to 1 part by weight of acetylacetonato complex-added polysilazane, and the particularly preferable amount of addition is in the range of 0.2 parts by weight to 3 parts by weight. is there. Further, the surface of the filler may be surface-treated by a coupling agent treatment, vapor deposition, plating or the like for use.

The coating composition may contain various pigments, leveling agents, defoaming agents, antistatic agents, ultraviolet absorbers, pH adjusters, dispersants, surface modifiers, plasticizers, and drying accelerators, if necessary. Alternatively, anti-flow agents may be added. According to the invention,
In the same manner, there is provided a coating method using the coating composition as described above, which comprises applying the coating composition to a substrate once or more than once and then baking the silicon-nitrogen-containing material. It is characterized in that a coating film made of oxygen-metal element ceramics or silicon-nitrogen-oxygen-carbon-metal element ceramics is formed.

The present invention also provides a coating method characterized in that the coating film baked as described above is kept at a temperature of less than 50 ° C. for a long time to improve the properties of the coating film. Further, the present invention further comprises applying the coating composition as described above to the substrate once or twice or more, and then holding the coating film at a temperature of less than 50 ° C. for a long time to obtain a silicon-nitrogen-oxygen-metal element system or Provided is a coating method, which comprises forming a coating film made of silicon-nitrogen-oxygen-carbon-metal element ceramics.

The substrate on which the coating composition is applied is not particularly limited and may be any of metal, ceramics, plastics and the like. As a coating means for coating, a usual coating method, that is, dipping, roll coating, bar coating, brush coating, spray coating, flow coating or the like is used. Further, if the substrate is sanded, degreased, and surface-treated with various blasts before coating, the adhesion performance of the coating composition is improved.

After being coated by such a method and sufficiently dried, it is heated and baked. By this firing, the acetylacetonato complex-added polysilazane is crosslinked, condensed, or is oxidized and hydrolyzed depending on the firing atmosphere to be cured to form a tough coating. The firing conditions differ depending on the molecular weight and structure of the acetylacetonato complex-added polysilazane. The heating rate is not particularly limited, but is 0.5 to 10 ° C.
A slow heating rate of / min is preferred. The preferred firing temperature is in the range of 250 ° C to 350 ° C. The firing atmosphere may be oxygen, air, or an inert gas, but the air is more preferable. Oxidation of acetylacetonato complex-added polysilazane by hydrolysis in air or hydrolysis by water vapor coexisting in air progresses, and Si—O bond or Si—
It is possible to form a tough coating mainly composed of N bonds.

Depending on the type of acetylacetonato complex-added polysilazane to be coated, conversion to ceramics may be incomplete under limited firing conditions.
In this case, the properties of the coating film can be improved by keeping the coating film after firing at a temperature of less than 50 ° C. for a long time. In this case, the holding atmosphere is preferably air, and more preferably wet air having an increased water vapor pressure. The holding time is not particularly limited, but 10 minutes or more and 30
Within a day is realistically appropriate. The holding temperature is not particularly limited, but 0 ° C or more and less than 50 ° C is practically appropriate. Here, it is naturally effective to hold at 50 ° C. or higher, but in the present text, the heating operation at 50 ° C. or higher is defined as “baking”. That is, it is also effective to bake at a certain temperature for a certain period of time and then lower the temperature to, for example, 50 ° C. and bake for a long time, but this operation is one type of the above-mentioned “heating / baking” operation.

By this retention in air, oxidation of acetylacetonato complex-added polysilazane or hydrolysis by water vapor coexisting in air further progresses, conversion to ceramics is completed, and properties are further improved. A tough coating film can be formed. According to the above method, the firing temperature can be lowered and various problems caused by the high firing temperature can be alleviated.

Further, depending on the kind of the acetylacetonato complex-added polysilazane to be coated, baking at 50 ° C. or higher is not performed at all, and the coating film after coating is kept for a long time at a temperature of less than 50 ° C. It is possible to improve the property of. In this case, the holding atmosphere is preferably air, and more preferably wet air having an increased water vapor pressure. The holding time is not particularly limited, but 1
0 minutes or more and 30 days or less is practically appropriate. The holding temperature is not particularly limited, but 0 ° C or more and less than 50 ° C is practically appropriate. Here, it is naturally effective to hold at 50 ° C. or higher, but in the present text, the heating operation at 50 ° C. or higher is defined as “baking”. Oxidation of acetylacetonato complex-added polysilazane by holding in air,
Alternatively, hydrolysis by water vapor coexisting in the air progresses, conversion to ceramics is completed, and it becomes possible to form a tough coating film mainly composed of Si—O bond or Si—N bond. According to the above method, various problems caused by the high firing temperature can be significantly reduced, and in some cases, conversion to ceramics near room temperature becomes possible.

[0040]

[Production of raw material perhydropolysilazane]

A four-necked flask having an inner volume of 11 was equipped with a gas blowing tube, a mechanical stirrer, and a dewar condenser. After replacing the inside of the reactor with deoxygenated dry nitrogen, 490 ml of degassed dry pyridine was put into a four-necked flask, and this was ice-cooled. Next, 51.6 g of dichlorosilane was added to produce a white solid adduct (SiH ₂ Cl · 2C ₅ H ₅ N). The reaction mixture was ice-cooled, and while stirring, 51.0 g of purified ammonia was bubbled through the sodium hydroxide tube and the activated carbon tube to heat.

After the reaction was completed, the reaction mixture was centrifuged, washed with dry pyridine, and then filtered under a nitrogen atmosphere to obtain 850 ml of a filtrate. The solvent was removed from the filtrate (5 ml) by distillation, and 0.1 g of a resinous solid perhydropolysilazane was obtained. The number average molecular weight of the obtained polymer was measured by the freezing point depression method (solvent: dry benzene),
It was 903. IR (infrared absorption) spectrum (solvent:
Concentration of dry o-xylene; perhydropolysilazane: 1
0.2 g / 1) is a wave number (cm ⁻¹ ) 3340 (apparent extinction coefficient ε = 0.5571 g ⁻¹ cm ⁻¹ ), and N of 1175.
H-based absorption; SiH-based absorption of 2160 (ε = 3.14); SiH and SiNSi of 1024-820
Showed absorption based on. ^{The 1} H NMR (proton nuclear magnetic resonance) spectra (60 MHz, solvent CDCl ₃ / reference material TMS) all show broad absorption. That is,
δ 4.8 and 4.4 (br., SiH); 1.5 (b
r. , NH) absorption was observed.

Comparative Example 1 (Evaluation of Ceramization during Firing) Generally, when polysilazane is fired, Si—R ₁ and N—R ₂ (R ₁ and R ₂ represent a hydrogen atom or an alkyl group) bond is broken. And S
Formation of i-N and Si-O bonds (the latter is limited to firing in an oxidizing atmosphere) occurs, polysilazane is silicon nitride,
Converts to ceramics such as silicon oxynitride and silica. This process is called ceramization. In this Comparative Example or Example, since the polysilazane was mainly changed to silica because the firing was performed in the air atmosphere, the semi-quantitative evaluation of the progress of the ceramization was performed by the IR method.

SiH residual rate = (SiH absorbance after heating /
(SiN absorbance before heating) × 100 (%) SiO / SiN ratio = SiO absorbance after heating / S after heating
iN Absorbance Both numerical values serve as indicators of the progress of ceramization, and the smaller the SiH residual rate and the larger the SiO / SiN ratio, the more advanced the ceramization.

The characteristic absorptions of SiN, SiO, and SiH used here are about 840, 1160, and 2160 cm ^-1 , respectively. The absorbance was calculated by the equation: absorbance = log (I _o / I). (See FIG. 1 for the definition of I _o and I)

Example 1 Tonen Perhydropolysilazane Type-1 (PHPS
-1; 0.05 g of palladium acetylacetonate (manufactured by Strem Chemicals. Inc., purity 99%) was added to 113.6 g of a 4.4% pyridine solution having a number average molecular weight of 600 to 900), and the temperature was 50 ° C. in a nitrogen atmosphere. The reaction was carried out with stirring for 2 hours. This solution was depressurized to remove the solvent and then diluted with xylene to give a 10% xylene solution. The number average molecular weight of this solution was 1267 as measured by GPC. In addition, as a result of the IR spectrum analysis, the wave number (cm) was compared with that before the reaction with palladium acetylacetonate.
^-1 ) CH2 absorption of 2960 and 2940 was confirmed. As a result of ¹ H NMR spectrum (CDCl ₃ ) analysis, absorption of δ = 1.4 was confirmed. This solution is used as a coating solution and applied on a silicon wafer having a diameter of 4 inches and a thickness of 0.5 mm by using a spin coater (1000 rp).
m 2 for 20 seconds) and heated at 350 ° C. for 1 hour in an air atmosphere to obtain a coating film having a film thickness of 3132Å. When the degree of progress of ceramization of this coating film was evaluated by IR (the evaluation method is the same as that of glycidol system), the SiH residual ratio is 6%, SiO / Si
The N ratio was 6.1 (Fig. 2). Furthermore, this coating film is 49%
When treated with a mixed solution of 18 ml of hydrofluoric acid (manufactured by Daikin Industries, Ltd.) and 1763 ml of 61% nitric acid (manufactured by Kosou Chemical Co., Ltd.), the etching rate was 1078 Å / min. On the other hand, a coating solution of polysilazane to which palladium acetylacetonate was not added was applied and evaluated in the same process. SiH residual ratio was 21%, SiO / S
iN ratio = 1.1, etching rate 2335Å / min.
That was all. (Figure 3). (See Table 1)

Example 2 Using platinum acetylacetonate, the reaction, construction and evaluation were performed in exactly the same manner as in Example 1. The number average molecular weight of this solution was 1086. As a result of the IR spectrum analysis, CH-based absorption of wave numbers (cm ⁻¹ ) 2960 and 2940 was confirmed as compared with that before reaction with platinum acetylacetonate. In addition, ¹ H NMR spectrum (CDCl ₃ )
As a result of the analysis, absorption of δ = 1.4 was confirmed. Furthermore, the coating film after heating has a film thickness of 3435Å, SiH residual ratio 6%, SiO
/ SiN ratio = 3.14, etching rate is 1290Å
/ Min. (See Table 1)

Example 3 Using rhodium acetylacetonate, the reaction, construction and evaluation were performed in exactly the same manner as in Example 1. The number average molecular weight of this solution was 901. Film thickness after heating is 3693
Å, SiH residual rate 2%, SiO / SiN ratio = 3.18,
The etching rate was 1086Å / min. (Table 1
reference)

[0048]

[Table 1]

[0049]

EFFECTS OF THE INVENTION According to the present invention, a coating having excellent heat resistance, abrasion resistance, corrosion resistance and good adhesion to a substrate can be obtained by firing at a low temperature which has never been seen before. The composition of the present invention is suitable as a surface protective agent for not only metals and ceramics but also plastic materials unsuitable for high temperature treatment and electronic parts. In particular, plastic hard coating agents, synthetic resin films and coatings for gas permeation suppression of containers, semiconductor protective films and insulating films, that is, passivation films, interlayer insulating films,
It can be used as a chip coat film, a semiconductor sealant, an undercoat film or an alignment film for liquid crystal displays.

[Brief description of drawings]

FIG. 1 is an IR spectrum diagram evaluating a ceramic of a comparative example.

2 is an IR spectrum diagram for evaluating the ceramic of Example 1. FIG.

3 is an IR spectrum diagram for evaluating the ceramic of Example 1. FIG.

Claims (3)

[Claims] 1. Mainly represented by the general formula (I): (However, R ¹ , R ² and R ³ are each independently a hydrogen atom,
An alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or a group other than these groups in which the group directly bonded to silicon is carbon, an alkylsilyl group, an alkylamino group, and an alkoxy group. However, at least one of R ¹ , R ² and R ³ is a hydrogen atom. The number average molecular weight having a main skeleton and 100-50000 polysilazane comprising units represented by), the general formula (CH ₃ COCHCOCH ₃₎
acetylacetonato complex / polysilazane weight ratio obtained by reacting an acetylacetonato complex represented by _n M [wherein M represents a metal having an ionic valence n] of 0.000.
In the range of 001 to 2 and a number average molecular weight of about 200 to 50
A coating composition containing at least acetylacetonato complex-added polysilazane. 2. The coating composition according to claim 1, wherein the metal M of the acetylacetonato complex is at least one selected from nickel, platinum, palladium, aluminum and rhodium. 3. The coating composition according to claim 1 or 2 is repeatedly applied to a substrate once or twice or more,
A coating method comprising forming a coating film made of silicon-nitrogen-oxygen-metal element ceramics or silicon-nitrogen-oxygen-carbon-metal element ceramics by firing at a temperature of 50 ° C or higher.