JPH0832853B2 - Coating composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a coating composition, and more specifically, metal, stainless steel, aluminum, concrete,
It has a transparent and glossy appearance on the surface of cement, slate, wood, paper, glass, plastic, etc., and has adhesion, weather resistance, heat resistance, corrosion resistance, abrasion resistance, flame resistance, moisture resistance, and resistance. Water permeability, chemical resistance, acid resistance, especially alkali resistance,
The present invention relates to a coating composition suitable for providing a coating film having excellent water resistance and the like.

[Conventional technology]

In recent years, adhesion, weather resistance, heat resistance, corrosion resistance, wear resistance,
There is a demand for a coating composition which is excellent in flame resistance, moisture resistance, water permeability, chemical resistance, acid resistance, particularly alkali resistance, water resistance, etc. and which can form a coating film.

An acidic aqueous composition containing a partial condensate of silanol and colloidal silica has been proposed as a coating composition that satisfies a part of such a requirement (Japanese Patent Publication No. Sho.
No. 52-39691).

[Problems to be Solved by the Invention] However, the coating composition described in JP-B-52-39691 is a lower alcohol-water solution containing a partial condensate of silanol containing monomethyltrisilanol as a main component. Disperse the aqueous colloidal silica in,
Although the pH is adjusted to 3 to 6, the partial condensation of silanol does not proceed sufficiently, and even if a coating film is formed using this composition, the adhesion of the coating film to the substrate is not sufficient. Further, since the siloxane bond of the coating film is hydrolyzed, there are drawbacks such as poor alkali resistance and water resistance.

The present invention has been made against the background of the above-mentioned problems of the prior art. Adhesion, weather resistance, heat resistance, corrosion resistance, abrasion resistance, flame resistance, moisture resistance, water permeability, chemical resistance, acid resistance. It is an object of the present invention to provide a coating composition which is excellent in alkali resistance, water resistance and the like and can form a coating film having high hardness which can be used for applications such as corrosion prevention and insulation.

[Means for solving problems]

That is, the present invention provides (a) the general formula RSi (OR ') ₃ (wherein R represents 1 to 8 carbon atoms).
And R'represents an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms. ), Which is an organoalkoxysilane represented by the formula (1), wherein an organopolysiloxane composed of a condensate of organoalkoxysilane containing 80 mol% or more of CH ₃ Si (OR ′) ₃ (R ′ is the same as above) is converted into organoalkoxysilane. 100 parts by weight, (b) 5 to 50 parts by weight of colloidal silica dispersed in a hydrophilic organic solvent (hereinafter simply referred to as "colloidal silica"), (c) 0.1 to 50 parts by weight of water (D) 50 to 500 parts by weight of a hydrophilic organic solvent (however, including the hydrophilic organic solvent present in the component (b)), and (e) a heterocyclic compound containing 2 to 3 nitrogen atoms, a general formula
Al (OR ³ ) _n [OC (R ⁴ ) = CHCOR ⁵ ] _3-n (wherein R ³ and R
⁴ is an alkyl group, R ⁵ is an alkyl group or an alkoxy group,
n shows the integer of 0-3. ) A coating composition containing at least 0.01 to 5 parts by weight of at least one selected from the group consisting of an aluminum compound, a partial hydrolyzate of the aluminum compound, and a partial condensate of the aluminum compound. Is provided.

 Next, the composition of the present invention will be described in detail for each constituent element.

(A) Organopolysiloxane Organopolysiloxane is obtained by hydrolyzing and polycondensing an organoalkoxysilane represented by the general formula RSi (OR ′) ₃ , and in the composition obtained by the present invention, It functions as a binder.

R in the organoalkoxysilane has 1 carbon atom
~ 8 organic groups, for example, methyl group, ethyl group, n-
Alkyl groups such as propyl group and i-propyl group, γ-chloropropyl group, vinyl group, 3,3,3-trifluoropropyl group, γ-glycidoxypropyl group, γ-methacryloxypropyl group, γ- Mercaptopropyl group, phenyl group, 3,4-epoxycyclohexylethyl group, γ
-Aminopropyl group and the like.

R 'in the organoalkoxysilane is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an i-
Examples thereof include propyl group, n-butyl group, sec-butyl group, t-butyl group, acetyl group and the like.

Specific examples of these organoalkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane and i-propyltrimethoxysilane. Silane, i-propyltriethoxysilane, γ-prolopropyltrimethoxysilane, γ-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3, 3,3-trifluoropropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane,
γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyl Examples thereof include triethoxysilane, γ-aminopropyltrimethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, and 3,4-epoxycyclohexylethyltriethoxysilane, but methyltrimethoxysilane and methyltrimethoxysilane are preferable. It is ethoxysilane.

These organoalkoxysilanes may be used alone or in combination of two or more.

However, the organoalkoxysilane has the general formula RS
Of the organoalkoxysilanes represented by i (OR ′) ₃ , 80 mol% or more is CH ₃ Si (OR ′) ₃ .

The organoalkoxysilane releases an alcohol by hydrolysis in an acidic aqueous medium and causes polycondensation to produce an organopolysiloxane.

The polystyrene-converted weight average molecular weight of such organopolysiloxane is preferably 500 to 5,000, particularly preferably 600 to 3,000, and if it is less than 500, cracks easily occur in the coating film obtained, while if it exceeds 5,000, curing of the coating film occurs. It tends to be insufficient.

(B) Colloidal silica (b) The component is used for increasing the solid content while maintaining the transparency of the composition of the present invention, and the thickness of the coating film obtained is controlled by the amount of the component. You can do it.

Here, the colloidal silica is a dispersion liquid in which a high-purity silicic acid anhydride is dispersed in a hydrophilic organic solvent described later, and usually has an average particle size of 5 to 30 mμ, preferably 10 to 20 mμ, and a solid content concentration. It is about 10 to 40% by weight.

Examples of such colloidal silica are commercially available from Nissan Chemical Industry Co., Ltd., isopropanol silica sol and methanol sol; Catalyst Chemical Industry Co., Ltd., Oscar and the like.

The ratio of the above colloidal silica in the composition is 5 to 5 per 100 parts by weight of the component (a) in terms of solid content.
0 parts by weight, preferably 10 to 40 parts by weight. If it is less than 5 parts by weight, it is difficult to achieve a thick coating film obtained by coating, and the hardness is low, while if it exceeds 50 parts by weight, a thick film is obtained. Although it is easily achieved, the coating film is likely to be cracked, and the weather resistance and water resistance are deteriorated.

(C) Water Water is an essential component for the hydrolysis of the organoalkoxysilane used as the starting material for the component (a).

As such water, general tap water, distilled water, ion-exchanged water or the like can be used. In particular, when making the composition of the present invention highly pure, distilled water or ion-exchanged water is preferable.

The proportion of water in the composition is 0.1 to 50 parts by weight, preferably 1 to 30 parts by weight, relative to 100 parts by weight of the component (a). If the amount is less than 0.1 parts by weight, hydrolysis will be insufficient, resulting in a composition. The coating film may not be sufficiently cured even if it is coated with a substance, while if it exceeds 50 parts by weight, the storage stability of the composition decreases, which is not preferable.

(D) Hydrophilic organic solvent The hydrophilic organic solvent contains the hydrophilic organic solvent present in the component (b), mainly mixes the components (a) to (b) uniformly, and (a) to (b). ) The concentration of the components is adjusted to adjust the solid content of the composition of the present invention, and at the same time, it can be applied to various coating methods to improve the dispersion stability of the composition.

As such a hydrophilic organic solvent, alcohols or low-boiling hydrophilic organic solvents having a boiling point of 120 ° C. or lower are suitable.

Examples of alcohols include monohydric alcohols and dihydric alcohols, and among these, monohydric alcohols are preferably saturated aliphatic alcohols having 1 to 8 carbon atoms. Specific examples of these alcohols include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, sec-butyl alcohol, t-butyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, and ethyl acetate. Lenglycol monoethyl ether and the like can be mentioned.

Further, examples of the low boiling hydrophilic organic solvent having a boiling point of 120 ° C. or lower include acetone, methyl ethyl ketone, and tetrahydrofuran.

Of these hydrophilic organic solvents, alcohols such as i-propyl alcohol, sec-butyl alcohol, n-propyl alcohol, n-butyl alcohol, diethylene glycol, and ethylene glycol monoethyl ether acetate are preferable, and i is particularly preferable. -Propyl alcohol and ethylene glycol monoethyl ether acetate.

These hydrophilic organic solvents may be used alone or in combination of two or more.

The ratio of the hydrophilic organic solvent in the composition is 100% of the component (a).
It is 50 to 500 parts by weight, preferably 100 to 400 parts by weight with respect to parts by weight, and if it is less than 50 parts by weight, the dispersibility of the organopolysiloxane and other fillers to be described later, which are optionally used, becomes poor, Further, the viscosity of the obtained composition becomes too high to obtain a uniform coating film, while when it exceeds 500 parts by weight, other components become relatively small, and the composition thus obtained is formed by coating. In some cases, the adhesiveness of the coating film may deteriorate, or the coating film may be too thin to obtain the desired coating film.

(E) Heterocyclic compound containing 2-3 nitrogen atoms, general formula
At least one selected from the group consisting of an aluminum compound represented by Al (OR ³ ) _n [OC (R ⁴ ) = CHCOR ⁵ ] _3-n , a partial hydrolyzate of the aluminum compound, and a partial condensate of the aluminum compound. The seed (e) component serves to improve the hardness, water resistance, and alkali resistance of the resulting coating film.

Examples of the heterocyclic compound containing 2 to 3 nitrogen atoms in the component (e) include pyrazole, 2-pyrazoline,
Pyrazoles such as benzopyrazole, imidazole,
Imidazoles such as methylimidazole, benzimidazole, 2-imidazoline and imidazolidine, 1,2-
Diazines such as diazine, 1,3-diazine, 1,4-diazine, benzo [L] pyridazine, benzo [d] pyridazine, quinazoline and quinazine, 1,8-diazabicyclo [5,4,0] -7 -Undecene, 1,5-diazabicyclo [4,3,0] -5-nonene, cyclic diazines such as 1,2-dimethyl-1,4,5,6-tetrahydropyrimidine, 1H-1,2,
3-triazole, 1H-1,2,4-triazole, triazoles such as benzotriazole, and the like, preferably, benzimidazole, 1,3-diazine, 1,8-diaza-bicyclo [5,4,0] -7-undecene, 1,5-diaza-bicyclo [4,3,0] -5-nonene, more preferably
1,8-diaza-bicyclo [5,4,0] -7-undecene is mentioned.

On the other hand, R ³ in the aluminum compound is preferably an alkyl group having 2 to 5 carbon atoms, such as an ethyl group or i
-Propyl group, n-propyl group, n-butyl group, sec-
Examples thereof include a butyl group, a t-butyl group, an n-pentyl group, an i-pentyl group and a sec-pentyl group.

Further, R ⁴ in the aluminum compound is preferably an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an i-propyl group and an n-butyl group.

Further, R ⁵ in the aluminum compound is preferably an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 18 carbon atoms, for example, methyl group, ethyl group, i-propyl group, n-propyl group, n -Butyl group, sec-butyl group,
Examples thereof include t-butyl group, methoxy group, ethoxy group, n-propoxy group, n-butoxy group, octadecanoxy group and the like.

Specific examples of these aluminum compounds include, for example, aluminum ethylate, aluminum propylate, aluminum isopropylate, sec-butoxyaluminum diisopropylate, aluminum sec-butyrate, aluminum sec-amylate, ethyl acetoacetate aluminum diisopropylate, acetyl. Acetonate aluminum diisopropylate, alkyl acetoacetate aluminum diisopropylate, diethyl malonate aluminum diisopropylate, bis (acetylacetate) aluminum isopropylate, bis (ethylacetoacetate) aluminum isopropylate, aluminum tris (ethylacetoacetate), Aluminum tris (acetylacetonate), aluminum monoa Such as chill acetonate bis (ethyl acetoacetate) may be cited. Among these aluminum compounds, ethyl acetoacetate aluminum diisopropylate and acetylacetonate aluminum diisopropylate are preferable.

In addition, a partial hydrolyzate of an aluminum compound and /
Alternatively, the partial condensate can be obtained by adding water to the hydrophilic organic solvent containing the aluminum compound to the extent that precipitation or gelation does not occur.

The above heterocyclic compound, aluminum compound, partial hydrolyzate of the aluminum compound, and partial condensate of the aluminum compound may be used alone or in combination of two or more.

The proportion of the component (e) in the composition is 0.01 to 5 parts by weight, preferably 0.1 to 2 parts by weight, in the case of a heterocyclic compound, relative to 100 parts by weight of the component (a), an aluminum compound,
In the case of the partial hydrolyzate of the aluminum compound and / or the partial condensate of the aluminum compound (hereinafter referred to as “aluminum compound”), 0.01 to 5 parts by weight, preferably 0.02 to 1 part by weight, (e If the amount of component (a) is too small, the water resistance and alkali resistance of the resulting coating film will decrease, while if it is too large, the resulting coating film may crack.

When the above-mentioned heterocyclic compound is used as the component (e), the glossiness of the obtained cured coating film can be changed by adjusting the addition amount of the heterocyclic compound.

Generally, in the coating film, its glossiness is appropriately selected from glossy, semi-glossy or matte depending on the use, customer preference and the like.
It has a feature that the glossiness can be freely changed by changing the amounts of the components.

That is, the glossiness can be lowered by increasing the addition amount of the component (e).

Since the change also changes depending on the surface condition of the applied substrate, that is, mainly the smoothness, the amount of the component (e) is
It is appropriately selected depending on the surface condition of the base material.

In addition, especially when the above heterocyclic compound is used, the coating film
It has the effect of curing at low temperatures below 100 ° C.

As described above, the coating composition of the present invention contains the components (a) to (e), and the total solid content concentration thereof is preferably 5 to 45% by weight, particularly preferably 8 to 30%.
% By weight, and if less than 5% by weight, the solid content is too thin, and various properties such as heat resistance, water resistance, chemical resistance, and weather resistance of the coating film formed by subjecting the composition to coating are obtained. It may not be expressed, and pinholes may be generated in the formed coating film. On the other hand, when it exceeds 45% by weight, the solid content concentration is too high and a uniform coating film is obtained even when the composition is used for coating. There are cases in which adverse effects such as difficulty in forming occur.

The composition comprising the components (a) to (d) has good storage stability, and the composition of the present invention containing the component (e) added thereto has excellent alkali resistance and water resistance.

In addition, it is possible to add other fillers to the composition of the present invention, if necessary.

Such fillers are insoluble in water and may include, for example, organic or inorganic pigments.

In addition, particulate or fibrous metals and alloys other than pigments and oxides, hydroxides, carbides, nitrides, sulfides and the like, of which specific examples are particulate or fibrous iron, copper, aluminum, nickel, Silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium oxide, aluminum oxide, chromium oxide, manganese oxide, iron oxide, zirconium oxide, cobalt oxide, synthetic mullite, zircon (zirconia silicate), aluminum hydroxide, water Examples thereof include iron oxide, silicon carbide, silicon nitride, boron nitride, molybdenum disulfide, and the like, but are not limited thereto.

The average particle size or average length of these fillers is usually
0.05 to 50 μm, preferably 0.1 to 5 μm, 0.05 μm
If it is less than m, the viscosity of the composition tends to increase, while if it exceeds 50 μm, the dispersibility of the resulting composition tends to deteriorate.

The proportion of the other filler used in the composition as needed is usually 50 to 500 parts by weight per 100 parts by weight of the component (a).
The amount of the filler is preferably 80 to 300 parts by weight, and if it is less than 50 parts by weight, the performance of the filler imparted to the composition cannot be sufficiently exhibited, and the purpose such as anticorrosion film and cosmetic film is achieved. It is not possible, on the other hand, if the amount exceeds 500 parts by weight, the resulting composition may gel, and the hardness of the coating film obtained by subjecting to coating deteriorates and the adhesion to the substrate deteriorates, Workability also deteriorates.

In addition, the selection of other fillers used as needed is performed based on, for example, the following selection depending on the purpose of the coating film to be obtained.

As a filler for forming the anticorrosion film, silicon dioxide,
Titanium oxide, aluminum oxide, chromium oxide, zirconium oxide, synthetic mullite, zircon, silicon carbide, silicon nitride or the like having excellent corrosion resistance is used.

An electrically insulating metal oxide, a carbide, or a nitride containing no alkali metal is used as a filler for forming the electrically insulating film.

As a filler for making a decorative film, iron oxide, titanium dioxide, cobalt oxide, zinc oxide, tin oxide, lead oxide,
An oxide such as aluminum oxide is used.

As a filler for forming the heat radiation film, an oxide such as iron oxide, copper oxide, cobalt oxide, manganese oxide, chromium oxide, silicon dioxide, titanium oxide, aluminum oxide, or zircon is used.

Copper, aluminum, nickel, silver, carbon black, tin oxide or the like is used as a filler for forming the conductive film or the semi-conductive film.

As the filler for forming the heat insulating film, a metal oxide, a hydroxide, a nitride or the like having a low thermal conductivity is used.

Zinc, lead, chromium, or the like is used as a filler for forming a rust prevention film.

In addition, two or more kinds of the above-mentioned fillers can be used in combination in order to produce a coating film that makes use of the characteristics of various fillers.

In addition, the composition of the present invention usually has a pH of 2.5 to 6.5, preferably 3 to 6 in order to accelerate the curing of the coating film after coating while keeping the storage stability of the composition before coating.
It is desirable to adjust to. Such pH adjustment can be achieved by adding various acids to the composition separately, if necessary.

Such acids include, for example, inorganic acids such as nitric acid and hydrochloric acid,
Or acetic acid, formic acid, propionic acid, maleic acid, chloroacetic acid, citric acid, benzoic acid, dimethylmalonic acid, glutaric acid, glycolic acid, malonic acid, toluenesulfonic acid,
Organic acids such as oxalic acid can be mentioned, but acetic acid is particularly preferable.

Further, the composition of the present invention includes various surfactants, silane coupling agents, titanium coupling agents, naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminic acid, carbonic acid and other alkali metal salts, dyes and the like. Other additives can also be added.

The composition of the present invention containing the components (a) to (e) as described above is, for example, (a) an organoorganic compound represented by the general formula RSi (OR ') ₃ which is a starting material of the component (a). Mixing 5 to 50 parts by weight of (b) colloidal silica in terms of solid content, (c) 15 to 65 parts by weight of water, and (d) 10 to 200 parts by weight of hydrophilic organic solvent to 100 parts by weight of alkoxysilane. Then, hydrolysis and polycondensation are performed to form an organoalkoxysilane into an organopolysiloxane. (B) Then, if necessary, a hydrophilic organic solvent which is the component (d) is further added, and the total amount of the component (d) is changed. 50-500 parts by weight to prepare a composition containing components (a)-(d), and then (c) by mixing 0.01-5 parts by weight of component (e) before coating. It

Here, the addition amount of the component (c) in the step (a) is
15 to 6 per 100 parts by weight of organoalkoxysilane component
5 parts by weight, preferably 15 to 50 parts by weight. If it is less than 15 parts by weight, hydrolysis and polycondensation of the organoalkoxysilane will be slow, the reaction will take a long time, and (c) in the resulting composition The amount of water is 100 parts by weight of component (a)
May be less than 0.1 parts by weight, while if more than 65 parts by weight hydrolysis and polycondensation may be too fast gelled product may undesirably undesirably, further water in the finally obtained composition. May be too large.

Further, when the amount of the component (d) added in the step (a) exceeds 500 parts by weight with respect to 100 parts by weight of the organoalkoxysilane, the amount of the hydrophilic organic solvent relatively increases too much to cause hydrolysis of the organoalkoxysilane. Also, the polycondensation becomes slow, and the reaction for obtaining the composition of the present invention requires a long time, which is not preferable.

The molar ratio of component (c) / organoalkoxysilane in step (a) is preferably 1.5 to 5. When it is less than 1.5, hydrolysis and polycondensation are difficult to proceed, while when it exceeds 5, component (e) is component. The storage stability of the composition before addition may decrease.

In this step (a), the organoalkoxysilane and the components (b) to (d) are usually mixed and stirred at a temperature of 10 to 90 ° C., preferably 20 to 80 ° C., and a reaction time of 1 to
It is carried out under the condition of 10 hours, preferably 2 to 8 hours.

Then, as a step (b), further step (d)
Add additional ingredients. That is, (b) step, (a)
After the completion of hydrolysis and polycondensation in the process, the produced organopolysiloxane is further hydrolyzed and polycondensed during storage to prevent the polymer from having a high molecular weight and further to adjust the solid content concentration of the entire composition. It is what makes up.

The addition amount of the component (d) in the step (b) is 0 to 490 parts by weight with respect to 100 parts by weight of the organoalkoxysilane, so that the total amount of the component (d) is 50 to 50 parts by weight.
The amount is 500 parts by weight.

In addition, the addition amount of the (d) hydrophilic organic solvent in the step (b) is within the above range in the composition (d) in the obtained composition.
The amounts of the components are appropriately selected so that they fall within the composition range of the present invention.

Further, in the present invention, the components (c) and (e) are additionally added before coating to the composition having excellent storage stability containing the components (a) to (d) thus prepared. It is a thing.

In addition, in the method for producing the composition of the present invention, in the case where other fillers and the like used as necessary are further compounded, the following production method may be adopted in accordance with the production method. .

That is, the organoalkoxysilane, (b) to
By mixing the component (d) and the above-mentioned filler,
Step (b), and then step (c) is performed.

Alternatively, the filler may be added separately in the step (b) after mixing the (a) organoalkoxysilane and the components (b) to (d).

The coating composition of the present invention is, on the surface of a base material such as metal, stainless steel, aluminum, concrete, cement, slate, glass, plastic, wood and paper, which is an organic or inorganic type. Drying film by coating once on the surface of the coating film, etc. by using a coating means such as brush, spray, dipping, etc., and curing at room temperature for about 1 day or at a temperature of about 60 to 300 ° C for about 10 to 60 minutes. A coating film with a thickness of 1 to 20 μm can be formed, and when a filler is contained, it is 5 to 100 μm, preferably 1
It is possible to form a coating film of about 0 to 80 μm.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples.

In the examples, parts and% are based on weight unless otherwise specified.

In addition, gel permeation chromatography (GP
The measurement of the weight average molecular weight in terms of polystyrene by the method C) and various measurements in the examples are as follows.

The measurement by the GPC method was carried out under the following conditions using tetrahydrofuran as a solvent and using organopolysiloxane
1 g was dissolved in 100 cc of tetrahydrofuran to prepare a sample. The standard polystyrene used was Standard Polystyrene manufactured by Pressure Chemical Co., USA.

Equipment: Waters, USA, high-temperature high-performance gel permeation chromatogram (model 150-C ALC / GPC) Column: Showa Denko KK, SHODEX A-8M, length 50 cm Measurement temperature: 40 ° C Flow rate: 1 cc / min Storage Stability is (a) ~ before adding the (e) component
The component (d) was sealed and stored in a polyethylene bottle at room temperature, and the presence or absence of gelation was visually determined to measure the time for gel formation.

Adhesion was based on the average of three tape peel tests after a cross cut test according to JIS K5400.

 The hardness was based on the pencil hardness according to J1S K5400.

The heat resistance was maintained in an electric furnace at 400 ° C. for 240 hours, allowed to cool naturally, and the state of the coating film was observed.

For water resistance, the coating film was immersed in tap water at room temperature for 60 days, and the state of the coating film was observed.

Water resistance is 60 at room temperature in saturated calcium hydroxide solution.
It was immersed for a day and the state of the coating film was observed.

The boiling water resistance was measured by boiling in tap water for 24 hours and observing the state of the coating film.

For boiling water resistance, the state of the coating film was observed by boiling in tap water for 48 hours.

Regarding the acid resistance, 1 ml of hydrochloric acid having a concentration of 20% was dropped on the coated cotton, allowed to stand for 1 day in a petri dish with a lid, washed with water, and the state of the coated film was observed.

Regarding the alkali resistance, 1 ml of sodium hydroxide having a concentration of 2% was dropped on the surface of the coating film, allowed to stand for 1 day in a petri dish with a lid, and then washed with water to observe the state of the coating film.

Regarding the alkali resistance, 1 ml of 4% concentration of sodium hydroxide was dropped on the surface of the coating film, allowed to stand for 1 day in a petri dish with a lid, washed with water, and the state of the coating film was observed.

Regarding the weather resistance, an irradiation test was conducted with a sunshine weather meter according to J1S K5400 for 5,000 hours, and the state of the coating film was observed.

The gloss is a value (%) measured according to JIS H4001.

In addition, ◯, Δ, and x in Tables 2 to 5 are based on the following.

 ○: No abnormalities.

Δ: Peeling, rust generation, erosion, contamination, etc. were observed in part.

X: Almost or all peeling, rust generation, erosion, contamination, etc. were observed.

Example 1 and Comparative Example 1 In a reactor equipped with a reflux condenser and a stirrer, organoalkoxysilane and methanol-dispersed colloidal silica (solids concentration 30%, manufactured by Nissan Chemical Industries, Ltd.) at the ratios shown in Table 1. ), Methanol sol), tap water, and a hydrophilic organic solvent are added and reacted under the conditions shown in Table 1. A mixture of organopolysiloxane, colloidal silica, water, and hydrophilic organic solvent A to D was prepared. The storage stability of this mixture A to D is shown in Table 1.

Further, a heterocyclic compound was added to the mixtures A to D at a ratio shown in Table 2 to obtain coating compositions a to j and k to n.

Then, it was immersed in a 5% aqueous solution of a degreasing agent for aluminum (PS-500A, manufactured by Koei Kogyo Co., Ltd.) at room temperature for 1 hour, washed with water, dried, and then alkali degreased aluminum plate (JIS H4
000, A2024P) and the resulting compositions a to j and k to
n was spray coated and heated at 150 ° C. for 30 minutes to form a cured coating film. The obtained coating film was tested for adhesion, hardness, heat resistance, water resistance, boiling water resistance, acid resistance, alkali resistance and weather resistance.

 The results are shown in Table 2.

Next, a slate plate (JIS A5403) was coated with an inorganic coating agent (Nippa Kenkyusho Co., Ltd., Glasca 1100) at a dry film thickness of 40 μm, and a substrate heat-treated at 150 ° C. for 30 minutes was prepared.

On this substrate, the compositions a to j and k shown in Table 2 were
~ N was spray coated and heated at 150 ° C for 30 minutes to form a cured coating film. The obtained coating film was tested for adhesion, hardness, water resistance, boiling water resistance, acid resistance, alkali resistance, weather resistance, and gloss. The results are shown in Table 3.

Example 2 and Comparative Example 2 Aluminum compounds were added to the mixtures A to D shown in Table 1 in the proportions shown in Table 4 to obtain coating compositions o to u and v to y. .

Then, the obtained compositions o to u and v to y are spray-coated on an aluminum plate in the same manner as in Example 1,
It was heated to form a cured coating film.

The obtained coating film was tested for adhesion, hardness, heat resistance, water resistance, boiling water resistance, acid resistance, alkali resistance and weather resistance. The results are shown in Table 4.

Next, similarly to Example 1, the compositions o to u and v to y shown in Table 4 were similarly spray-coated on a substrate using a slate plate and heated to form a cured coating film. . The obtained coating film was tested for adhesion, hardness, water resistance, boiling water resistance, acid resistance, alkali resistance, weather resistance and gloss.

 The results are shown in Table 5.

Example 3 The compositions a to j obtained in Example 1 were heated for 1 hour in the same manner as in Example 1 to form a cured coating film. The obtained coating film was tested in the same manner as in Example 1 and the same results as in Example 1 were obtained.

(Effect of the invention) The coating film obtained from the composition of the present invention has a transparent and glossy appearance, and has excellent weather resistance, heat resistance, corrosion resistance, abrasion resistance, flame resistance, moisture resistance, and resistance to abrasion. It is excellent in water permeability, stain resistance, solvent resistance, chemical resistance, and adhesiveness, and in particular, since it contains the above-mentioned component (e), it has excellent anti-aliasing property and water resistance.

Furthermore, those containing a filler as needed, depending on the type of filler to be added, heat resistance, water resistance, water permeability, chemical resistance, acid resistance, alkali resistance, heat and light absorption and radiation, Anti-corrosion film excellent in abrasion resistance, weather resistance, flame resistance, moisture resistance, adhesion, etc., electric insulation film, decorative film, absorption / emission film, rust prevention film, conductive film, semiconductor film, flame retardant film, heat insulating film A cured film, a protective film, a functional film, etc. can be made.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshinori Yoshida, Inventor Yoshinori Yoshida, 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd. (56) Reference JP-A-58-101164 (JP, A) Kai 56-88468 (JP, A)

Claims (1)

[Claims] (A) General formula RSi (OR ') ₃ (wherein R is an organic group having 1 to 8 carbon atoms, R'is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms). An organoalkoxysilane represented by the formula: CH ₃ Si (OR ′)
100 parts by weight of organopolysiloxane composed of a condensate of organoalkoxysilane containing 80 mol% or more of ₃ (R 'is the same as above) in terms of organoalkoxysilane, (b) colloidal silica dispersed in a hydrophilic organic solvent. 5 to 50 parts by weight in terms of solid content, (c) 0.1 to 50 parts by weight of water, (d) hydrophilic organic solvent (however, including the hydrophilic organic solvent present in the component (b)) 50 to 500 parts by weight. Part, and (e) a heterocyclic compound containing 2 to 3 nitrogen atoms, a general formula Al (OR ³ ) _n [OC (R ⁴ ) = CHCOR ⁵ ] _3-n (wherein R ³ and R ^3
4 is an alkyl group, R ⁵ is an alkyl group or an alkoxy group,
n shows the integer of 0-3. ) A coating composition containing 0.1 to 5 parts by weight of at least one selected from the group consisting of the aluminum compound, the partial hydrolyzate of the aluminum compound, and the partial condensate of the aluminum compound. .