JP3284066B2 - Composition for coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to coating compositions, and more particularly to concrete or cement based, calcium silicate based, gypsum based, other ceramic based substrates, or iron, aluminum, stainless steel, etc. Inorganic base materials such as metal materials and stone materials, or wood, paper,
It is non-flammable or flame-retardant, has good adhesion, and is weather-resistant, heat-resistant, water-resistant, and alkali-resistant by being applied to the surface of organic base materials such as fibers and dried and cured at room temperature or under low-temperature heating. The present invention relates to a coating composition for forming a coating film having excellent acid resistance, organic solvent resistance, impact resistance, stain resistance, and drying property (humidity control property).

[0002]

2. Description of the Related Art Conventionally, heat resistance, weather resistance,
For the purpose of improving chemical resistance, stain resistance and the like, various coating compositions for forming a coating film by drying at room temperature or at low temperature have been proposed. For example, a silicone resin-based composition, a fluororesin-based composition, an alkoxysilane-based composition, a silicate-based composition, and the like are disclosed. However, silicone resin-based compositions, fluororesin-based compositions and alkoxysilane-based compositions have problems in hardness and chemical resistance when dried at room temperature or at low temperature,
By becoming more hydrophobic, it is easy to rain dripping,
There is a problem with stain resistance. In addition, the silicate-based composition has problems such as water resistance, chemical resistance, and cracking (due to too fast or too fast dehydration condensation reaction). As described above, the conventional coating composition cures by heating at room temperature or low temperature, is nonflammable, has weather resistance of 25 years or more, has appropriate hardness, can easily form a thick film, has water resistance,
At present, it has good hot water resistance, alkali resistance, and acid resistance, and is hydrophilic, but has remarkably good drying properties, hardly dripping, and has not obtained a coating film excellent in stain resistance.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is a stable aqueous one-part composition having good workability and the basic physical properties of an inorganic coating film. ,
The film is hardly cracked by a moderate dehydration condensation reaction with little impairment of nonflammability, weather resistance, heat resistance, water resistance and warm water resistance, it is easy to form a thick film, good impact resistance, and Because it becomes hydrophilic, it is difficult to get dirt like raindrops,
Moreover, it is an object of the present invention to provide a coating composition capable of obtaining a coating film having an advantage that dehydration is not performed due to very good drying property and that mold and algae are not generated.

[0004]

According to the present invention, there is provided (a) acidic colloidal silica comprising _2.5 to 15 parts by weight in terms of SiO ₂ ;
(B) 0.1 to 15 parts by weight of an amine compound, (c) 10 to 80 parts by weight of an inorganic filler, and (d) 17 to 87 parts by weight of water and / or a hydrophilic organic solvent (provided that (a) +
(B) + (c) + (d) = 100 parts by weight].

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION

(A) acidic colloidal silica; (a) acidic colloidal silica is a colloidal solution of pure silicic anhydride in which the pH of the solution is acidic. This (a)
Acidic colloidal silica is a single-particle polymer silica sol having a silanol group on the surface of a siloxane bond. When gelled, this polymer single particle causes condensation and dehydration of the silanol group to form a siloxane-bonded chain. To form a three-dimensional siloxane bond network,
Multimerizes into pure silica gel. This (a) acidic colloidal silica is used as a binder of the composition. In addition, when (a) the acidic colloidal silica is used alone, only a film having a thickness of 0.1 to 0.3 μm can be formed, and it is hardly used. A coating film having a thickness of 1 to 300 μm can be formed.

(A) The composition of the acidic colloidal silica is usually such that the content of silicic anhydride (SiO ₂ ) is 10 to 25% by weight, preferably 20 to 21% by weight, and sodium oxide (N
a ₂ O) = 0.04% by weight or less, PH = 1-6, preferably 2-4, average particle size = 10-50 nm, preferably 10-20 nm, viscosity [25 ° C. (mPas)] = 1
5, preferably 3 or less, specific gravity (20 ° C.) = 1 to 1.2,
Preferably it is 1.11 to 1.14. Specific examples of this (a) acidic colloidal silica include Snowtex O and Snowtex OL manufactured by Nissan Chemical Industries, Ltd.
Catalyst Kasei Kogyo Co., Ltd., Cataloid SN, Asahi Denka Kogyo Co., Ltd., Adelite AT-20Q, and the like.

The proportion of the component (a) in the coating composition of the present invention is 2.5 to 15 parts by weight, preferably 5 to 10 parts by weight in terms of SiO ₂ . If the amount is less than 2.5 parts by weight, the bonding strength is insufficient, while if it exceeds 15 parts by weight, a coating film cannot be formed or cracks occur.

(B) an amine compound; (b) an amine compound, which is combined with the (a) acidic colloidal silica to make the pH alkaline, and (c) an inorganic filler having a large surface area in a particulate or fibrous form; It functions to react with and bond to a functional group such as a hydroxyl group on the surface. Thus, when the composition of the present invention is applied to a substrate, the coating film is cured by a dehydration condensation reaction at room temperature or under low temperature heating, and is nonflammable, high weather resistance, high heat resistance, water resistance, alkali resistance, It is possible to produce a film that is excellent in acid resistance, organic chemical resistance, contamination resistance, drying property (humidity control property) and impact resistance.

(B) Specific examples of the amine compound include isopropylamine, diisopropylamine, iminobispropylamine, ethylamine, diethylamine, triethylamine, 2-ethylhexylamine, 3-ethoxypropylamine, diisobutylamine, and 3-diethylaminopropylamine. , Dibutylaminopropylamine, tetramethylethylenediamine, tri-n-octylamine, t-butylamine, propylamine, methylaminopropylamine, allylamine, diallylamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, amino Ethylethanolamine, N, N-dibutylethanolamine, N-methylethanolamine, ethanolamine, diethanolamine, triethanolamine Ammonia, morpholine, and the like. These amine compounds (b) can be used alone or in combination of two or more.

The proportion of the amine compound (b) in the coating composition of the present invention is 0.1 to 15 parts by weight, preferably 0.1 to 5 parts by weight. If the amount is less than 0.1 part by weight, the pH of the composition will not be alkaline, and the bonding strength will be insufficient. If the amount exceeds 15 parts by weight, the amine odor, drying property,
It is not preferable from the environmental point of view.

(C) an inorganic filler; (c) an inorganic filler is necessary for forming a thick film, and is further used for coloring a coating film and imparting various functions to the coating film. It imparts deodorant properties, antibacterial properties, humidity control properties, heat radiation properties, ultraviolet absorption properties, heat insulation properties, conductivity, and the like. The inorganic filler (c) used in the coating composition of the present invention has an average particle diameter or an average length of preferably 0.1 to 100 μm, more preferably 0.1 to 2 μm.
One having a thickness of 0 μm is used. When the average particle size is less than 0.1 μm, the functionality of the inorganic filler cannot be exhibited or the production cost is excessively increased. On the other hand, when the average particle size is more than 100 μm, the coating film becomes rough or the adhesion becomes poor. Or drop. The inorganic filler (c) is preferably a water-insoluble, particulate or fibrous material, and includes at least one selected from the group consisting of inorganic extender, functional pigment, inorganic pigment and metal powder. be able to.

(C) Specific examples of the inorganic filler include commercially available silica, alumina, kaolin, zircon, tin oxide, mullite, zeolite, talc, perlite, carbon, potassium titanate whisker, silicon carbide, silicon nitride, and commercially available inorganic filler. Titanium, iron, manganese, cobalt, chromium, nickel and other oxides and carbon or cobalt and aluminum, iron and manganese and other synthetic oxides, or iron,
Examples include, but are not limited to, three types of synthetic oxides such as copper and chromium, and metal powders such as zinc, nickel, stainless steel, aluminum, and tin.

The amount of the inorganic filler (c) is 10 to 80 parts by weight, preferably 25 to 6 parts by weight, in the composition of the present invention.
5 parts by weight. If the amount is less than 10 parts by weight, the function of the inorganic filler cannot be exhibited and the film cannot be made thicker. On the other hand, if it exceeds 80 parts by weight, the adhesion or hardness decreases, the viscosity increases, and (a) Component (b) or component (d) is insufficient, which is not preferable.

(D) water and / or a hydrophilic organic solvent;
Water used in the coating composition of the present invention is an essential component for adjusting the viscosity of the composition, adjusting the pot life, and dispersing the inorganic filler. As this water, tap water, distilled water, and ion-exchanged water can be used. In addition, water contains (a)
Water and the like contained in the acidic colloidal silica are also included.

On the other hand, the hydrophilic organic solvent used in the present invention is an organic solvent which is compatible with water, and is used as an agent for controlling the solid concentration and viscosity of the coating composition of the present invention and also as a drying speed adjusting agent. I do.

The hydrophilic organic solvents used in the present invention include alcohols, glycols, esters, ethers, ketones and the like. Alcohols have 1 to 1 carbon atoms
And aliphatic alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol, sec-butanol, t-butanol, methyl carbitol and the like. As glycols,
For example, ethylene glycol, propylene glycol, diethylene glycol and the like can be mentioned. Examples of the esters include esters of the above-mentioned alcohols and glycols such as formic acid, acetic acid, and propionic acid, specifically, methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, and ethyl propionate. it can.

Examples of the ethers include alkyl ethers of the alcohols and glycols, such as dimethyl ether, diethyl ether, dibutyl ether, methyl ethyl ether, ethyl butyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate and propylene. Glycol monoethyl ether and the like. Ketones include acetone, diethyl ketone, methyl ethyl ketone and the like.

The hydrophilic organic solvent can be used alone or as a mixture of two or more solvents. In the present invention, i-propanol, methyl carbitol and methyl ethyl ketone are used alone or as a mixed solvent of two or more thereof. Is preferably used.

The proportion of the component (d) in the coating composition of the present invention is 17 to 87 parts by weight, preferably 25 to 50 parts by weight. (D) The compounding ratio of the component is 1
If the amount is less than 7 parts by weight, the viscosity of the coating composition will increase too much, and the storage stability will decrease, or if the dispersing power of the component (c) will be poor. Although the other components are relatively reduced, the adhesion of the film of the obtained material may be weakened, or the film may be too thin to produce the desired product.

Since the composition of the present invention contains (a) acidic colloidal silica and a basic (b) amine compound, the pH of the resulting composition becomes alkaline. In order to adjust the pH of the composition of the present invention and improve the adhesion, the pH of the obtained composition is adjusted to 9 to 12, preferably 10 to 11 by blending an alkalinizing agent or a pH adjuster. You can also. As the alkalizing agent or the pH adjusting agent, for example, sodium hydroxide,
Examples include sodium silicate, potassium silicate, lithium silicate and the like. These alkalizing agents or pH adjusters can be used alone or in combination of two or more.

In addition to the above components (a) to (d), the coating composition of the present invention may further contain various surfactants, dispersing agents, curing regulators, resin emulsions and water-soluble agents as adhesion assistants, if necessary. Resin, organic dyes and pigments, and other additives.

The resin used as the bonding aid serves not only as a binder for the resulting coating film but also for improving the impact resistance. Specifically, acrylic resin, epoxy resin, alkyd resin, etc. , A vinyl acetate resin, a urea resin, a phenol resin, a melamine resin, a polybutadiene resin, and the like, but are not limited thereto. These resins are usually used in an emulsion type or a water-soluble type as described above. For example, the resin mixes well with water and when dried, forms a transparent or translucent film that is insoluble in water, and is used in the present invention to adhere the components (a) and (c). Things.

Further, specific examples of the above-mentioned resin of the emulsion type include vinyl acetate resin emulsion, acrylic resin emulsion, acryl-styrene copolymer emulsion, styrene-butadiene copolymer emulsion, acryl-modified urethane resin emulsion and the like. Can be Specific examples of the water-soluble type include a water-soluble melamine resin, a water-soluble epoxy resin, a water-soluble phenol resin, a water-soluble polybutadiene, a water-soluble acrylic resin, and the like.

The coating composition of the present invention comprises (a)
-Component (c) is mixed, and when component (d) is insufficient, component (d) is further blended as necessary, and the total solid content concentration is preferably 15 to 85% by weight, and It is preferably prepared at 30 to 75% by weight. At this time, the coating composition of the present invention is dispersed by a high-speed stirrer, a roll mill, a ball mill, or another disperser, and filtered to obtain a uniform and stable dispersion.

The substrate to which the coating composition of the present invention is applied includes metal materials such as iron, stainless steel and aluminum; inorganic substrates such as cement, concrete, glass and ceramics; and organic materials such as paper and wood. This is the surface of the substrate.

For applying the coating composition to the substrate, coating means such as brushing, spraying, dipping, roll coating, and printing can be used. Here, in order to apply the coating composition of the present invention to the surface of a substrate, it is possible to apply 2 to 30 in terms of solid content per 1 m ² at a time.
0 g, preferably 10-200 g of the composition is applied.
This can be performed several times, but usually, the total applied amount is 4 to 400 in terms of solid content per 1 m ^2.
g, preferably 10 to 200 g. This coating film has a dry film thickness of usually 2 to 200 μm, preferably 1 to 200 μm.
0 to 150 μm.

After the coating composition is applied, the composition is cured at room temperature at 5 to 30 ° C. for 1 to 8 hours, or at a temperature higher than 30 ° C. and 200 ° C. or lower, preferably 5 to 30 ° C.
The composition can be easily cured by heating at 0 to 150 ° C. for 5 to 40 minutes at a low temperature to obtain a coating film.

The coating film thus obtained comprises (a) acidic colloidal silica, (b) an amine compound and (c)
It is composed mainly of an inorganic filler. For this reason,
(A) acidic colloidal silica binds to (b) an amine compound, and has a large surface area in the form of particles or fibers (c)
Reacts with and binds to functional groups such as hydroxyl groups on the surface of the inorganic filler, and the coating film is cured by a dehydration condensation reaction under low-temperature heating. A film with excellent resistance to organic chemicals, stain resistance, drying (humidity control), and impact resistance can be obtained.

[0029]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the scope of the claims. In the examples, parts and% are based on weight unless otherwise specified.

Examples 1 to 6, Comparative Example 1 Seven types of compositions A to G shown in Table 1 were prepared. The above composition is added to a stirring tank in the form of components (a), (b) and (c),
Further, if necessary, the component (d) and / or other additives are added, and the mixture is gently stirred.
(000 rpm) for 30 minutes, and filtered through 50-100 mesh.

The symbols in Table 1 represent the following. (A) acidic colloidal silica (a) -1; Cataloid SN [manufactured by Catalyst Chemical Industry Co., Ltd.
SiO ₂ minutes 20-21%, pH 2 to 4] (a) -2; SNOWTEX O (manufactured by Nissan Chemical Industries, Ltd.)
Ltd., SiO ₂ minutes 20-21%, pH 2 to 4] (b) an amine compound (b) -1; triethanolamine (b) -2; ammonia water (ammonia concentration = 10%) (b) -3 ; morpholine

(C) Inorganic filler (c) -1; silicon dioxide (average particle size = 2 to 3 μm) (c) -2; kaolin (average particle size = 5 μm) (c) -3; potassium titanate whisker (Average length = 1
(C) -4; zinc oxide white (average particle size = 0.8 μm) (c) -5; titanium oxide white (average particle size = 0.5 μm) (C) -6; iron oxide black (average particle size = 0.5 μm) (c) -7; synthetic oxide (cobalt / aluminum) green (average particle size = 1 μm) (c) -8; zinc dust ( (Average particle size = 5 μm)

(D) water / hydrophilic organic solvent (d) -1; ion-exchanged water (d) -2; ethylene glycol (e) other additives (e) -1; leveling agent (silicone) (e) ) -2; acrylic resin emulsion (resin content 50)
%) (E) -3; sodium silicate (40% aqueous solution) (e) -4; caustic soda (10% aqueous solution)

[0034]

[Table 1]

Preparation of Test Pieces for Evaluation Test The coating compositions thus prepared were applied to the surfaces of various substrates shown in Table 2 and cured, and test pieces Nos. 1 to 16 for evaluation tests were applied. Was prepared. In the base material, steel plate, aluminum plate, stainless plate are treated with alkali,
In other cases, the cleaning treatment was performed as a base treatment before applying the coating composition. An air spray gun was used for applying the coating composition, and an electric oven was used for heating. Tables 3 to 5 show the number of application times and curing conditions of the coating composition.

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

[Table 4]

Evaluation Test After the test pieces prepared in Tables 3 to 5 above were kept in a room for 7 days, the following evaluation tests were performed. Adhesion: Based on JIS K-5400-8.5.1 cross cut test. Hardness: Based on JIS K-5400-8.4.2 pencil scratch test. Impact resistance: JIS K-5400-8.3.1 (25.
4 mm, 300 g × 20 cm).

Heat resistance: 400 test pieces in an electric furnace
After holding at 5 ° C. for 5 hours, the film was allowed to cool naturally and the appearance of the coating film was observed. Non-flammability: After exposed to the flame of city gas for 20 minutes, the appearance of the coating film (state of peeling, cracking, damage) was observed. Weather resistance: Using a sunshine carbon arc type weather meter based on JIS K5400-9.8.1,
After exposing the test piece for 5,000 hours, the appearance of the coating film was observed.

Drying property: 12 at 25 ° C. and 90% humidity
The amount of moisture absorption after time and the amount of moisture release after 3 hours at 25 ° C. and 50% humidity were measured. The upper part shows the amount of moisture absorption, and the lower part shows the amount of release (g). Warm water resistance: After the test piece was kept in warm water at 60 ° C. for 30 days, the appearance of the coating film was observed.

Salt spray resistance: 5% saline was sprayed continuously on a test piece for 960 hours, and the appearance of the coating film was observed. Alkali resistance; 5% aqueous solution of sodium carbonate was dropped on a test piece, and after holding for 8 hours, the appearance of the coating film was observed. Acid resistance; drop 20% hydrochloric acid aqueous solution
After holding for a time, the appearance of the coating film was observed. Solvent resistance: After the test piece was rubbed 100 times with a cloth soaked with methyl ethyl ketone, the appearance of the coating film was observed.

Stain resistance: a process of preparing a suspension using a contaminant containing a mixture of loess, carbon black, clay, etc., dropping the suspension on the surface of a test piece and drying the same, was repeated 10 times, and then the appearance of the coating film was observed. Was observed.

The evaluation of the appearance of the coating film was evaluated as follows. ：: No peeling of the coating film was observed, and there was no change in appearance. ×: Peeling, cracking, erosion, or dirt is observed in part or all of the coating film. -: No evaluation The results of the above evaluation tests are shown in Tables 6 and 7.

[0045]

[Table 6]

[0046]

[Table 7]

[0047]

According to the coating composition of the present invention, a stable aqueous one-pack type composition having good workability is applied to the surface of an organic, inorganic or metal base material to form an inorganic or inorganic base composition. The coating film is hardly cracked by a moderate dehydration condensation reaction with little impairment of the basic physical properties of the coating film, such as nonflammability, weather resistance, heat resistance, water resistance and hot water resistance. It has good impact resistance and is also hydrophilic, so it is hard to get dirt such as rain dripping, and it has very good drying properties so that dew condensation does not occur and there is an advantage that mold and algae are not generated. It is possible.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C09D 1/00-201/10

Claims (2)

(57) [Claims] (1) An acidic colloidal silica is made of SiO ₂
2.5 to 15 parts by weight, (b) 0.1 to 15 parts by weight of an amine compound, (c) 10 to 80 parts by weight of an inorganic filler, and (d) water and / or a hydrophilic organic solvent 17 to 87. Parts by weight [(a) + (b) + (c) + (d) = 100
Parts by weight]. (C) the inorganic filler has an average particle size or an average length of 0.1 to 100 μm and is water-insoluble;
The coating composition according to claim 1, wherein the composition is at least one selected from the group consisting of an inorganic extender, a functional pigment, an inorganic pigment, and a metal powder.