JPH0154389B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an anticorrosive coating composition that can form a tough film with excellent weather resistance and anticorrosion properties. Traditionally, steel structures installed outdoors have been painted with an undercoat that takes into account the ability to block moisture and corrosion-promoting substances, adhesion to metal surfaces, and inhibit corrosion using rust-preventing pigments. An intermediate coating having physical properties intermediate between the undercoat and topcoat is applied for the purpose of improving adhesion between the topcoat, mitigating the effects of differences in physical properties between the undercoat and topcoat, and adding film thickness. Furthermore, it is common to apply a top coat that has good appearance, weather resistance, mechanical strength, etc. Such a coating system may consist of paints from the same family, or may consist of a combination of paints of different types. Traditionally, top coats include alkyd resin paints,
Chlorinated rubber paints, vinyl resin paints, epoxy resin paints, polyurethane paints, etc. are used.
Resins and pigments deteriorate due to ultraviolet rays, etc., resulting in discoloration, chalking, cracking, etc., resulting in decreased gloss and fading, and long-term weather resistance cannot be expected. ~6
It had to be repainted every year. In addition, silicone resins have recently been considered for use in topcoat paints as resins with good weather resistance, but silicone alkyd resins, silicone acrylic resins, etc. that dry at room temperature have soft coating surfaces that are easily stained and scratched. It had the defect of whitening. Furthermore, even if the above-mentioned resin does not deteriorate over a long period of time and has a glossy appearance, the pigment on the surface layer of the coating film fades and the color changes greatly from the initial color tone, so that it cannot withstand long-term use. In addition, scale-like oxide-containing paints or silver paints made by kneading scale-like iron oxide or aluminum powder may be used as top coats, but these can only produce a single color, blackish brown or silver, and are not required for top coats. A major limitation was that it was not possible to obtain a wide range of color tones, which limited its use. The present inventors have solved these various conventional problems and have invented a coating composition that is capable of producing a wide range of color tones and has excellent weather resistance. That is, the present invention provides: (a) at least one color vehicle selected from alkyd resins, phenolic resins, chlorinated rubber resins, vinyl resins (excluding acrylic resins), silicone resins, fluororesins, and polyurethane resins; 100 parts by weight, and (b) molten colored glass made into hollow spheres, obtained by cooling, crushing, and classifying, with an average thickness of 0.5 to 10 μm;
The present invention relates to an anticorrosive coating composition comprising 10 to 150 parts by weight of flat glass flakes with an average size of 100 to 400 μm and uniformly colored throughout. The color vehicle used in the present invention includes alkyd resins (including modified alkyd resins such as phenol-modified and acrylic-modified resins), phenolic resins, chlorinated rubber resins, vinyl resins (excluding acrylic resins), silicone resins (acrylic resins), The synthetic resin is at least one type of synthetic resin selected from the group consisting of modified silicone resins (including modified silicone resins), fluororesins, and polyurethane resins. The colored glass flakes used in the coating composition of the present invention are vitreous, extremely thin colored flat particles with an average thickness of 0.5 to 10 μm, preferably 1 to 6 μm, and an average size of 100 to 400 μm, preferably 150 to 300 μm. be. The colored glass flakes are layered in parallel to the material within the film, increasing the strength of the resin, and at the same time blocking the penetration of external vapors, moisture, and other environmental agents, as well as blocking ultraviolet rays. to shield. Furthermore, since the colored glass flakes have almost no deterioration due to ultraviolet rays, there is no discoloration or fading of the coating film using the colored glass flakes, and therefore, the coating film retains its original color. By using colored glass flakes such as those of the present invention, it is possible to prevent not only discoloration and fading of the coating film but also yoking and cracking, thereby further improving the anticorrosion properties of the coating film. In general, the thinner the colored glass flakes and the larger the diameter, the greater the inhibition effect, and this tendency becomes more pronounced in severe corrosive environments. In the present invention, the mixing ratio of the color vehicle (solid content: solid content including hardening agent if necessary) and colored glass flakes is based on 100 parts by weight of the resin content.
From the viewpoint of corrosion resistance, weather resistance, or physical properties, 10 to 150 parts by weight (particularly preferably 20 to 100 parts by weight) of colored glass flakes is suitable. In the above mixing ratio, the colored glass flakes are 10
If the part by weight is not calculated, the desired corrosion resistance or weather resistance of the coating film cannot be obtained, and conversely, 150
If the amount exceeds 1 part by weight, the film becomes less flexible and brittle, which is not preferable. Furthermore, the coating composition of the present invention may contain extender pigments, suspending agents, dispersants, diluents, other flat pigments,
It is possible to add solvents, curing agents, etc. The thus obtained coating composition of the present invention is applied onto an object to be coated to a thickness of 25 to 300 μ by a conventional method such as brushing, roller, or spraying, and then dried at room temperature or by heating. The coating film obtained after drying has excellent properties such as strength, corrosion resistance, and weather resistance. Furthermore, since the coating film obtained from the coating composition of the present invention exhibits particularly excellent weather resistance, it can be applied over primer coatings and intermediate coatings such as zinc-rich paints, wash primers, and synthetic resin sub-stop coatings. It is very useful as an anti-corrosion top coat. The details of the present invention will be explained below with reference to Examples and Comparative Examples. In addition, "parts" and "%" are "parts by weight"
and "% by weight". Example 1 Part soybean oil modified medium oil alkyd resin 30.0 (Oil length 50%, acid value 5) Colored glass flakes 30.0 Desiccant 5.0 Anti-skinning agent 1.0 Anti-settling agent 1.0 Mineral spit 33.0 100.0 Example 2 Part Soybean oil modified Medium oil type alkyd resin 15.0 (same as Example 1) Chlorinated rubber (manufactured by Asahi Denka Kogyo Co., Ltd.) 15.0 Chlorinated paraffin 40% 7.0 Colored glass flakes 20.0 Desiccant 2.0 Anti-skinning agent 0.5 Anti-settling agent 1.0 Xylol 39.5 100.0 Implementation Example 3 parts Chlorinated rubber (same as Example 2) 25 Chlorinated paraffin 40% 10 Colored glass flakes 30 Anti-settling agent 1.0 Xylol 34.0 100.0 Example 4 Parts Vinyl chloride resin (manufactured by Union Carbide, trade name: VYHH) 20.0 Dibutyl phthalate (DBP) 9.0 Colored glass flakes 10.0 Anti-settling agent 1.0 Methyl isobutyl ketone 30.0 Xylol 20.0 Butyl acetate 10.0 100.0 Example 5 Part Silicon alkyd resin (manufactured by Toshiba Silicon Co., Ltd., product name: YR3116: non-volatile content 48.3%) 40 Cobalt dryer 0.03 Lead dryer 0.4 Colored glass flakes 20 Anti-settling agent 1.0 Mineral spirits 38.57 100.00 Example 6 Part fluororesin 30 (Product name manufactured by Asahi Glass Co., Ltd.: AP-500: Non-volatile content 45%) Colored glass flakes 15 Polyisocyanate 5 (Japan Polyurethane) Co., Ltd. product name: Coronate HL) Dibutyltin dilaurate 50×10 ^-6 xylol 50 100 Example 7 Polyisocyanate (Mitsubishi Chemical Corporation product name Mitek GP/0/A: non-volatile content 75%) 29 Polyester resin (trade name: Tesmofen 1100, manufactured by Bayer) 9.1 Colored glass flakes 30 Xylol 6 Ethyl acetate 6 Butyl acetate 6 Cellosolve acetate 4.8 100.0 Example 8 Part phenolic resin (trade name: Tanol 1131, manufactured by Hitachi Chemical Co., Ltd.) 20 Soybean oil modified medium oil type alkyd resin (same as Example 1) 15 Toluene 20 Ethyl acetate 15 Colored glass flakes 30 100 Preparation of colored glass flakes used in the above examples: Part Silica sand 50.0 Cryolite 2.0 Soda ash 19.0 Bone Ash 1.0 Potassium carbonate 1.5 Salt 0.5 Borax 4.0 Selenium 1.0 Zinc white 7.5 Cadmium sulfide 1.3 The above composition was placed in a crucible and heated and melted at 1200 to 1300°C to produce colored glass. After attaching the above molten glass to the tip of a small-diameter pipe, air is blown from the opposite side to inflate it into a balloon shape and then cooled.Then, the balloon-shaped colored glass is crushed, and the crushed colored glass is classified using a sieve. Colored glass flakes (average size 150-200μ, thickness 3
~5μ) was obtained. Comparative example 1 part soybean oil modified medium oil alkyd resin (same as Example 1) 30 titanium oxide 10 desiccant 5 anti-skinning agent 1 anti-settling agent 1 mineral spirit 53 100 Comparative example 2 parts soybean oil modified medium oil alkyd resin (Same as Example 1) 25 Natural flaky iron oxide pigment (size 10-200μ, thickness 3-4μ) 45 Desiccant 5 Anti-skinning agent 1 Anti-settling agent 1 Mineral spirit 23 100 Comparative example 3 parts Soybean oil modified medium oil type alkyd resin (same as Example 1) 15.0 Chlorinated rubber (same as Example 2) 15.0 Chlorinated paraffin 40% 7.0 Titanium oxide 15.0 Desiccant 2.0 Anti-skinning agent 0.5 Anti-settling agent 1.0 Xylol 44.5 100.0 Comparison Example 4 Part soybean oil modified medium oil alkyd resin (same as Example 1) 15.0 Chlorinated rubber (same as Example 2) 15.0 Chlorinated paraffin 40% 7.0 Natural scaly iron oxide pigment (same as Comparative Example 2) 30.0 Dry Agent 2.0 Anti-skinning agent 0.5 Anti-settling agent 1.0 Xylol 29.5 100.0 Comparative example 5 parts chlorinated rubber (same as Example 2) 25 Chlorinated paraffin 40% 10 Titanium oxide 15 Anti-settling agent 1.0 Xylol 64.0 100.0 Comparative example 6 parts chlorinated rubber (Same as Example 2) 25 Chlorinated paraffin 40% 10 Natural scaly iron oxide pigment (Same as Comparative Example 2) 40 Xylol 25 100 Comparative Example 7 Part Acrylic resin (Product name manufactured by Dainippon Ink & Chemicals Co., Ltd.) Acrylic A-169, non-volatile content 50% 30 Titanium oxide 15 Anti-settling agent 1.0 Xylol 54 100 Comparative example 8 parts Acrylic resin (same as Comparative example 7) 30 Natural scaly iron oxide pigment (same as Comparative example 2) 30 Sedimentation Inhibitor 1.0 xylol 39.0 100.0 Comparative example 9 parts Vinyl chloride resin (same as Example 4) 20.0 Dibutyl phthalate (DBP) 9.0 Titanium oxide 10.0 Anti-settling agent 1.0 Methyl isobutyl ketone 30.0 Xylol 20.0 Butyl acetate 10.0 100.0 Comparative example 10 parts Vinyl chloride Resin (same as Example 4) 20.0 DBP 9.0 Natural scaly iron oxide pigment (same as Comparative Example 2) 30.0 Anti-settling agent 1.0 Methyl isobutyl ketone 20.0 Xylol 10.0 Butyl acetate 10.0 100.0 Comparative example 11 parts Epoxy resin (manufactured by Ciel) Product name: Epicote 834) 30 Titanium oxide 15 Anti-settling agent 1 Toluene 21.0 Isopropyl alcohol 15.0 Polyamide resin (Product name: Tomide 215, manufactured by Fuji Kasei Kogyo Co., Ltd.) 18.0 100.0 Comparative example 12 parts Epoxy resin (same as Comparative example 11) 20 Natural scaly iron oxide pigment (same as Comparative Example 2) 40 Antisettling agent 1.0 Toluene 16.0 Isopropyl alcohol 10.0 Polyamide resin (same as that used in Comparative Example 11) 13.0 100.0 Comparative example 13 parts Vinyl chloride resin (Example) 4) 30 Colored glass powder 30 Anti-settling agent 1 Xylol 39 100 The colored glass powder has a particle size obtained by simply crushing colored glass having the same composition as in the example and sieving it.
A powder of 60-800μ was used. When this powder was observed under a microscope, it was found to be an amorphous powder, far from flakes. Comparative example 14 parts vinyl chloride resin (same as example 4) 50 colored glass flakes (same as example) 4 anti-settling agent 1 xylol 45 100 comparative example 15 parts vinyl chloride resin (same as example 4) 20 colored glass flakes (Same as Example 4) 35 Anti-settling agent 1 Xylol 44 100 Comparative example 16 parts Vinyl chloride resin (Same as Example 4) 40 Colored glass flakes (thickness 12-20μ, size 150-200μ) 15 Anti-settling agent 1 Xylol 44 100 Comparative Example 17 parts Vinyl chloride resin (same as Example 4) 40 Colored glass flakes (thickness 3-5μ, size 50μ or less) 15 Anti-settling agent 1 Xylol 44 100 Comparative Example 18 parts Vinyl chloride resin (same as Example 4) Same as Example 4) 40 Colored glass flakes (thickness 3-5μ, size 600-1000μ) 15 Anti-settling agent 1 Xylol 44 100 Paints containing colored glass flakes in the paints shown in each of the above examples and comparative examples do not settle. The inhibitor was dispersed in advance using a conventional method, and then colored glass flakes were added and stirred using a disper. Other paints were prepared using conventional methods. After polishing the polished mild steel plate with sandpaper, degrease it with Triclean and apply a long-exposure type wash primer.
It was painted with a film thickness of 15 μm, and then a chlorinated rubber-based rust preventive paint was applied with a film thickness of about 50 μm, and each of the paints shown in the above examples and comparative examples was applied with a film thickness of about 50 μm, and then subjected to a comparative test. .

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[Table] It is clear from the Comparative Example Test Results Tables 1 and 2 that the coating film obtained from the coating composition of the present invention is superior to the comparative coating film obtained from the conventionally known coating composition. The weather resistance was further improved and the corrosion resistance was also excellent.

Claims (1)

[Scope of Claims] 1 (a) Alkyd resins, phenolic resins, chlorinated rubber resins, vinyl resins (excluding acrylic resins),
100 parts by weight of at least one color vehicle selected from silicone resins, fluororesins, and polyurethane resins, and (b) an average thickness obtained by shaping molten colored glass into hollow spheres, cooling them, crushing them, and classifying them. 0.5~10μm,
An anticorrosive coating composition comprising 10 to 150 parts by weight of flat glass flakes with an average size of 100 to 400 μm and uniformly colored throughout.