JPH0341232B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a rust-preventive coating finishing method for forming a tough film with excellent rust-preventive properties on steel structures, and a film that exhibits sufficient electrical resistance to remove static electricity. Conventionally, various highly corrosion-resistant coating compositions have been applied to steel structures to protect the coatings. However, the surface resistance of coating films obtained from commonly used anticorrosive paints shows a high resistance value of 10 ¹³ ohms/sq or more.
Most of them belonged to the insulator region. Steel structures coated with such insulators, especially tanks for storing fluids and piping such as pipes for moving fluids, are exposed to large amounts of water due to friction between the fluid moving inside and the coating surface. Static electricity is generated, and the generated static electricity accumulates on the surface of the paint film. As mentioned above, when the surface resistance is 10 ¹³ ohms/sq or more and exhibits high insulation properties, the coating film will be charged for a long time. Generally, when a good conductor approaches a statically charged object or other accidental causes, static electricity is sparked and grounded. In particular, in tanks that store flammable fluids, such as low boiling point, volatile solvents, or crude oil, naphtha, or gasoline that contain large amounts of these fluids, or pipes that transport them, a spark discharge can ignite and cause an explosion. There is a risk of fire. Conventionally, to remove static electricity, the surface resistance value was
It is known that a resistance of about 10 ¹¹ to 10 ⁶ ohm/sq is sufficient, and for this purpose, gold, silver,
Paint compositions in which conductive metal fine powders such as platinum, copper, and nickel are mixed into a color vehicle, or paints in which a carbon-based compound with a graphite structure or amorphous carbon that exhibits conductivity is mixed in a color vehicle. Compositions and the like are known. However, in the case of the former, there are practical problems because the fine metal powder is very expensive, and it is extremely difficult to obtain a resistance value (10 ¹¹ to 10 ⁶ ohms/sq) for eliminating static electricity. There was a problem. In particular, in the case of general-purpose copper and nickel, the voltage of the single electrode potential when the potential of the hydrogen electrode is set to 0 is Cu/
Cu ⁺⁺ : +0.34 mV, Ni/Ni ⁺⁺ : -0.23 mV, both of which are higher than iron (Fe/Fe ⁺⁺ : -0.44 mV). Therefore, when a paint containing such a substance is applied to an iron surface, iron becomes a cathode and corrodes faster than copper or nickel, which is a major problem in terms of corrosion protection. On the other hand, in the case of a coating composition using a carbon-based conductive substance, the electrical properties are sufficiently satisfied, but as mentioned above, the electrode potential of carbon is higher than that of iron, which is the material, resulting in accelerated corrosion of iron. Therefore, there was a problem in terms of corrosion protection. As mentioned above, in steel structures where static electricity tends to accumulate, there has been a strong desire for a coating system that can prevent fires and explosions caused by static electricity and also has excellent rust prevention properties. At present, a coating system is not available. In view of the current situation, the present invention aims to eliminate all the drawbacks and problems of the conventional technology, and has excellent rust prevention and static electricity removal properties, as well as ordinary coating film performance such as adhesive strength and durability. The purpose of this invention is to provide a rust-preventing coating finishing method that is as good as or better than other paints. That is, the present invention provides () a dry coating film with a thickness of 10 to
A process of applying zinc-rich paint to a thickness of 70 microns and drying it, () A process of applying an intermediate coat paint on the zinc-rich paint film and drying it, and () A process of applying a resin component of 100 μm on the intermediate coat film. A room temperature curable resin composition prepared by adding 80 to 400 parts by weight of a conductive white pigment, 0.01 to 5.0 parts by weight of a silane coupling agent, or 0.01 to 10.0 parts by weight of a titanium coupling agent is applied and dried. The present invention relates to a rust-proof coating finishing method comprising the following steps. The zinc-rich paint used in the present invention is 75 to 95% by weight, preferably 80 to 95% by weight in the dry coating film.
It is an organic or inorganic paint containing 90% by weight of zinc dust. The vehicle for organic zinc-rich paint is a combination of epoxy resin and polyamide resin.
Examples include chlorinated rubber, polystyrene resin, silicone resin, etc. Vehicles for inorganic zinc-rich paint include ethyl silicate, sodium silicate, lithium silicate, potassium silicate, ammonium silicate, etc. Preferred vehicles, particularly for purposes such as the present invention, are epoxy resin-polyamide resin combinations, ethyl silicates, potassium silicates, lithium silicates. In the finishing method of the present invention, first, the zinc-rich paint is applied by spraying, brushing, etc. to the steel surface, which has been sufficiently rust-removed by sandblasting or shotblasting. In the present invention, the thickness of the dry film of the zinc-rich paint is 10 to 70 microns, preferably
It is 15-40 microns. If the film thickness is less than 10 microns, the desired corrosion resistance cannot be obtained, and on the other hand, if the film thickness exceeds 70 microns, cohesive failure is likely to occur inside the dry coating layer of the zinc-rich paint. Due to severe impact, mechanical stress, heat shock, etc.
A drawback arises in that the resulting film is likely to peel off. In the finishing method of the present invention, the use of zinc-rich paint as the undercoat is due to the following:
The paint dries to the touch very quickly, in about 5 to 10 minutes.
Because the surface hardness of the cured coating is high, it takes several hours to dry to the touch like undercoats and paint primers used in normal finishing methods, and the surface is sticky and is susceptible to dust and sandblasting due to lack of hardness. This is because there are no drawbacks such as very high adhesion of sand, iron, iron powder, etc., which is extremely difficult to clean, or that the coating surface is often damaged. Furthermore, even when exposed outdoors or to rainwater, the cathodic anticorrosive hardening of zinc powder maintains its rust prevention properties for a long period of time. This increases the flexibility of coating, and significantly reduces rusting due to defects in the undercoat and peeling of the topcoat. In the finishing method of the present invention, the zinc-rich paint is applied, and after drying, an intermediate paint is applied. The intermediate coating may be one of the commonly used paints, such as alkyd resin paints, epoxy resin paints, vinyl resin paints, acrylic resin paints, urethane resin paints, and unsaturated polyester paints. Two or more types can be used. Therefore, one of the particularly preferred intermediate coatings for the rust-preventing coating finish of the present invention is an epoxy resin coating consisting of an epoxy resin and a curing agent. The epoxy resin is a resin having at least two epoxy groups in its molecule, and preferable examples include epoxy resins obtained by reacting polyhydric alcohols, polyphenols, etc. with excess epichlorohydrin or alkylene oxide. You can give resin. Examples of polyhydric alcohols are ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, glycerin, neopentyl glycol, butylene glycol, hexanediol, trimethylolethane,
These include trimethylolpropane, pentaerythritol, diglycerol, and sorbitol.
The polyhydric phenol is 2,2-bis(4-hydroxyphenyl)propane (generally referred to as bisphenol A). Halogenated bisphenol A, 4,4'-hydroxyphenylmethane (generally referred to as bisphenol F), tris(4-hydroxyphenyl)propane, resorcin, tetrahydroxyphenylethane, noorac type polyhydric phenol , cresol type polyphenol, etc. Other examples of epoxy resins that can be used in the present invention include 1,2,3-tris(2,3-epoxypropoxy)propane, glycidyl adducts of aniline or aniline derivatives (such as orthotoluidine), phthalic acid These include glycidyl esters such as diglycidyl ester, hexahydrophthalic acid diglycidyl ester, and tetrahydrophthalic acid diglycidyl ester, and epoxidized soybean oil. Further, as the curing agent, one or more of amino curing agents such as polyamines, polyamide resins, and amine adducts, which are usually used as curing agents for epoxy resins, can be used. Incidentally, when the epoxy resin and the curing agent are solid at room temperature, they are used after being dissolved in an organic solvent according to a conventional method. Another preferable example of the intermediate coating composition of the present invention is a room-temperature-curable liquid coating composition prepared by adding 10 to 60 parts by weight of a flat pigment to 100 parts by weight of the resin component. The resin component is preferably an unsaturated polyester resin and/or an epoxy resin. The unsaturated polyester resin is preferably a resin that is liquid at room temperature without being diluted with a solvent, and is a resin that can be cured with a curing agent or catalyst, and the cured coating film has excellent water resistance and chemical resistance. There is. Examples of these resins include generally commercially available isophthalic acid-based unsaturated polyester resins, bisphenol-based unsaturated polyester resins, and epoxy acrylate resins. Examples of the unsaturated polyester resin include, for example, U-Pica 5523 and 4529 (trade name) manufactured by Nippon U-Pica Co., Ltd., which are generally commercially available as isophthalic acid-based unsaturated polyester resins, and Rigorac 150HR (trade name) manufactured by Showa Kobunshi Co., Ltd. : Product name Atlatsu 38205, manufactured by Kao Atlas Co., Ltd., which is generally commercially available as a bisphenol-based unsaturated polyester resin: Showa Kobunshi Co., Ltd.
Product name Rigoratsu LP-1: Nippon U-Pica Co., Ltd. Product name U-Pica 5834, etc.: Kao Atlas Co., Ltd., which is generally commercially available as an epoxy acrylate resin. Product name Atlatsu G-6575: Showa Kobunshi Co., Ltd. Lipoxy R-800: Nippon U-Pica Co., Ltd., trade name Neopol 8250: Dainippon Ink & Chemicals Co., Ltd., trade name Deitzkrite 3505: Dow Chemical Co., Ltd. trade names Delakane 510 and 411. These resins are commercially available, usually containing 10 to 50% by weight of a liquid α,β-monoethylenically unsaturated monomer such as styrene or methyl methacrylate. Therefore, in the present invention, the unsaturated polyester resin includes monomers thereof. Further, as the epoxy resin, an appropriate one can be selected from the above-mentioned exemplified epoxy resins, but one that is liquid at room temperature is particularly preferred. Furthermore, the flat pigment has a thickness of 0.5 to 10 microns,
They are extremely thin flat inorganic particles with a size (maximum length) of 0.3 to 6 mm, and typical examples include glass flakes and mica powder. Particularly preferred are glass flakes. Of course, in the case of the unsaturated polyester resin, a curing agent such as a ketone peroxide such as methyl ethyl ketone peroxide, a hydroperoxide such as cumene hydroperoxide, or a peroxy ester such as t-butyl peroxyphthalate is used. In the case of epoxy resin, an amino curing agent such as polyamine, amine adduct or polyamide resin is used. Furthermore, it is particularly preferable that the room temperature curable liquid coating composition as the intermediate coating be used in an amount of 0.01 to 100 parts by weight based on 100 parts by weight of the resin content.
5.0 parts by weight of a silane coupling agent, which will be described later, can be added and mixed. In the method of the present invention, the corrosion resistance of the entire coating layer is improved by applying the intermediate coating, and
It plays an auxiliary role in improving the adhesion of the room-temperature curable resin composition used as a top coat to the zinc-rich paint film. In the finishing method of the present invention, the intermediate coating is applied to a film thickness of about 50 mm on the zinc-rich paint film.
Apply to a thickness of ~1000 microns and dry. Application methods include conventional methods such as brush, roller, spray, and trowel. Next, in the present invention, a cold-curable resin composition composed of a resin, a conductive white pigment, a silane coupling agent, or a titanium coupling agent is applied. The resin component in the room temperature curable resin composition is the above-mentioned epoxy resin, unsaturated polyester resin, etc., which is a resin used for ordinary paints that is cured with a curing agent or catalyst, and the cured coating film is water resistant and resistant. Those with excellent chemical properties are suitable. Suitable examples include unsaturated polyester resins (containing unsaturated monomers) such as bisphenol-type epoxy resins, isophthalic acid-based unsaturated polyesters, bisphenol-based unsaturated polyesters, and epoxy acrylates. These are cured using a curing agent as described above. The electrically conductive pigment used in the room temperature curable resin composition of the present invention is preferably a white pigment with an average particle size of 5 microns or less. In the present invention, the conductive pigment is used in order to make the hue of the room-temperature curable resin composition as a top coat paint variable, in other words, it can be freely colored with other coloring pigments that are normally added to top coat paints, and there are no restrictions on color. Since there is no pigment, it is necessary to use a white pigment. The pigment includes a white pigment such as titanium oxide on which a film of a conductive metal oxide such as In ₂ O ₃ , SnO ₂ , Sb ₂ O ₃ is formed, or a white pigment and a conductive metal oxide. (containing 20 to 90% by weight of conductive metal oxide). Particularly in the present invention, the former pigment is preferred. Suitable pigments include conductive white powder W-1 and W-2 manufactured by Mitsubishi Metals Co., Ltd. The mixing ratio of the resin component and the conductive white pigment in the present invention is 100 parts by weight of the former to 80 to 400 parts by weight of the latter.
parts by weight, preferably 100 to 350 parts by weight. If the conductive white pigment is less than 80 parts by weight in the above mixing ratio, the surface resistance of the formed coating film will be 10 ¹¹
If it exceeds ohm/sq, it will not be possible to obtain a sufficient resistance value to remove static electricity, and if it exceeds 400 parts by weight, the coating film will become brittle and the rust prevention properties will decrease, both of which are unfavorable. Furthermore, examples of the silane coupling agent used in the room temperature curable resin composition of the present invention include those of the general formula (However, R ¹ is a divalent hydrocarbon group having 1 to 4 carbon atoms,
R ² and R ³ are monovalent hydrocarbon groups having 1 to 4 carbon atoms,
Z is a hydrogen atom or an aminoalkyl group, m is 1 or 0), or an aminoalkoxysilane compound represented by the general formula (However, R ⁴ is a divalent hydrocarbon group having 1 to 4 carbon atoms,
R ⁵ and R ⁶ are monovalent hydrocarbon groups having 1 to 4 carbon atoms,
Q is an alkyl alkoxysilane compound represented by ethacryloxy group, acryloxy group, glycidoxy group, or epoxycyclohexyl group, and n is 1 or 0. Specific examples of the former compound include aminomethyltriethoxysilane, N-(β-aminoethyl)
Aminomethyltrimethoxysilane, aminomethyldiethoxysilane, N-(aminoethyl)aminomethyltributoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminoisobutyltrimethoxysilane, N -(β-aminoethyl)-γ-aminopropyltrimethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane and
-aminoethyl)-γ-aminopropylmethyldimethoxysilane and the like. Specific examples of the latter compounds include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, and β-glycidoxypropylmethyldimethoxysilane.
-3,4-epoxycyclohexyl)ethyltrimethoxysilane, β-3,4-epoxycyclohexyl)ethyltriethoxysilane, β-3,4
-epoxycyclohexyl)ethylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and the like. Furthermore, other silane coupling agents containing a vinyl group such as vinyltriethoxysilane and vinyltris-β-methoxyethoxysilane are also included in the present invention. The above silane coupling agent is 1
It can be used as a species or a mixture of two or more. In the present invention, among the silane coupling agents, it is particularly preferable to use an alkoxysilane compound represented by the above formula (2), and more preferably β-(3,4-epoxycyclohexyl).
The use of ethyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane and gamma-methacryloxypropyltrimethoxysilane is preferred. In addition, organometallic compounds such as dibutyltin dilaurate, dibutyltin di(2-ethylhexoate), stannous oleate, tin naphthenate, stannous chloride, and stannic chloride may be added to the silane coupling agent as a catalyst. can be added in an amount of 1% by weight or less. The Silica coupling agent is added in an amount of 0.01 to 5.0 parts by weight, preferably 0.1 to 2.0 parts by weight, per 100 parts by weight of the resin component. These silane coupling agents further improve the adhesion of the room-temperature curable resin composition to the intermediate coating, contributing to improved anticorrosion performance, and
In the resin composition, it helps to improve the affinity between the conductive white pigment, which is an inorganic material, and the resin component, which is an organic material, and therefore it is possible to improve the physical and chemical properties of the resulting film. Furthermore, examples of the titanium coupling agent used in the room temperature curable resin composition of the present invention include isopropyl triisostearoyl titanate, isopropyl trioctanoyl titanate, isopropyl diisostearoyl cumyl phenyl titanate, isopropyl distearoyl methacrylic titanate, Isopropyl dimethacrylylisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, lysopropyl diisostearoyl acrylic titanate, isopropyl isostearoyl diacryl titanate, isopropyl tris(dioctyl phosphate) titanate, isopropyl tri-n-stearoyl titanate, isopropyl 4-aminobenzene Sulfonyl bis(dodecylbenzenesulfonyl) titanate, isopropyl trichumyl phenyl titanate, isopropyl bis(4-aminobenzoyl)
Isostearoyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, isopropyl tris (octyl butyl pyrophosphate) titanate, tetraisopropyl bis (dilauryl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite)
Titanate, Tetraisopropylbis(ditridecylphosphite) Titanate, Tetra 2,2-
Diallyloxymethyl-1-butoxybis(ditridecyl)phosphite titanate, diisostearoyloxyacetate titanate, isostearoylmethacryloxyacetate titanate, isostearoylacryloxyacetate titanate, bis(dioctylphosphate)oxyacetate titanate, 4-aminobenzoyliso Stearoyloxyacetate titanate, bis(dioctylpyrophosphate)oxyacetate titanate, bis(octylbutylpyrophosphate)oxyacetate titanate, diisostearoylethylene titanate, isostearoylmethacrylethylene titanate,
Examples include bis(dioctyl phosphate) ethylene titanate, 4-aminobenzoyl isostearoyl ethylene titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl tri(N-aminoethyl aminoethyl) titanate, dicumyl phenyloxyacetate titanate, etc. It will be done. These titanium coupling agents may be used alone or as a mixture of two or more. In the present invention, among the titanium coupling agents, isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, bis(dioctyl pyrophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacrylic isostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumyl phenyl titanate, isopropyl tri(N-aminoethyl titanate) It is preferred to use one or a mixture of two or more of aminoethyl) titanate, dicumyl phenyloxyacetate titanate, and diisostearoyl ethylene titanate. The titanium coupling agent is used in an amount of 0.01 to 10.0 parts by weight, preferably 0.1 to 8.0 parts by weight, based on 100 parts by weight of the resin component. The titanium coupling agent also has the same effect as the silane coupling agent, which improves the physical properties of the coating layer.
Chemical properties can be improved. If the addition amount range of the silane coupling agent and titanium coupling agent is less than 0.01 part by weight, the effect of the present invention cannot be achieved. If the amount of the agent exceeds 10.0 parts by weight, it is not preferable because the rust prevention properties of the resulting film will deteriorate. The room-temperature curable resin composition of the present invention may be mixed with an organic solvent, a reactive diluent, etc. for pigment dispersion or as necessary for coating workability. In addition to the above additives, the room temperature curable resin composition used in the present invention includes general coloring pigments, extender pigments,
Dispersion aids, suspending agents, driers, curing accelerators, etc. can be added by conventional methods. The room temperature curable resin composition thus obtained is coated onto the intermediate coating film to a thickness of 50 microns or more with the addition of a curing agent such as an organic peroxide. Application methods include conventional methods such as brush, roller, spray, and trowel. Unless the film thickness of the resin composition is substantially 50 microns or more, it will not be very effective as a rust-preventive coating as the object of the present invention. The film obtained by the method of the present invention as described above not only has excellent static electricity removal properties and rust prevention properties, but also has improved interlayer tightness, and therefore has improved physical and chemical properties of the film as a whole. It is very useful as a rust-preventing coating for steel structures because of its improved corrosion performance. The details of the present invention will be explained below with reference to Examples. "Part" or "%" means "part by weight" or "% by weight"
It is shown with. Prior to Examples, a zinc-rich paint, an intermediate coating, and a room-temperature curable resin composition were prepared using the following formulations. [Formulation 1] Aqueous sodium silicate solution (solid content 40%) 30 parts zinc powder 70 [Formulation 2] Ethyl silicate solution 25 parts zinc powder 75 The ethyl silicate solution is manufactured by Nippon Colcoat Co., Ltd. under the trade name Colcoat 40 [solid content 40% alcohol solution] ;
A condensate mixture of linear and branched tetraethyl orthosilicate with an average degree of condensation of about 4 to 5 was used. [Formulation 3] (Main ingredient) Epoxy resin 6 parts Xylol 10 Methyl isobutyl ketone 9 Zinc dust 65 (Curing agent) Polyamide resin 4 Xylol 4 Isobutanol 2 The above epoxy resin is manufactured by Ciel Chemical Co., Ltd. under the trade name Epicote #1001 [Epoxy equivalent] 450 to 520], and the polyamide resin used was Tomide #210 (trade name, manufactured by Fuji Kasei Co., Ltd.) [amine value 95±5]. The above formulations 1 to 3 are formulations of zinc-rich paint, and each is mixed with zinc dust or zinc dust and a curing agent at the time of use. [Formulation 4] (Main ingredient) Isophthalic acid-based unsaturated polyester resin 50 parts Organic bentonite (anti-settling agent) 3.5 Silane coupling agent 0.1 Styrene 25.7 Cobalt naphthenate (contains 6% metallic cobalt)
0.7 Glass flakes 20 (hardening agent) Methyl ethyl ethone peroxide 0.7 The unsaturated polyester resin was manufactured by Showa Kobunshi Co., Ltd. under the trade name Rigoratsuku 150HR, and the organic bentonite was manufactured by National Red Co., Ltd. under the trade name Benton #34.
The silane coupling agent is a trade name manufactured by Shin-Etsu Chemical Co., Ltd.
KBM #503 [γ-methacryloxyuropyltrimethoxysilane] was used, and the glass flakes were manufactured by Nippon Glass Fiber Co., Ltd. under the trade name CF-150. [Formulation 5] (Main ingredient) Epoxy acrylate resin 60 parts Organic bentonite (same as formulation 4) 3.5 Silane coupling agent 0.2 Styrene 20.5 Cobalt naphthenate (same as formulation 4) 0.8 Glass flakes (same as formulation 4) 15 (hardening agent) ) Methyl ethyl ketone peroxide 1.2 The epoxy acrylate resin is manufactured by Showa Kobunshi Co., Ltd.
The silane coupling agent is KBM#303 [β-(3,
4-epoxycyclohexyl)ethyltrimethoxysilane] were used in each case. [Formulation 6] (Main ingredient) Epoxy resin (same as formulation 3) 30 parts Organic bentonite (same as formulation 4) 2 Xylene 16 Methyl isobutyl ketone 6 Glass flakes (same as formulation 3) 14 (Curing agent) Polyamide resin (same as formulation 3) 20 Xylene 6 Isobutanol 6 [Formulation 7] (Main ingredient) Epoxy resin (same as Formulation 3) 24 Titanium oxide 24 Methyl ethyl ketone 8 Cyclohexane 8 Xylene 16 (Curing agent) Polyamide resin 12 Methyl ethyl ketone 2 Cyclohexane 2 Xylene 4 The above polyamide resin Versamide 115, a trade name manufactured by Daiichi Kogyo Seiyaku Kogyo Co., Ltd., was used. The above formulations 4 to 7 are intermediate coating formulations, in which the main agent and curing agent are mixed and used, respectively. [Formulation 8] (Base ingredient) Isophthalic acid-based unsaturated polyester resin (Formulation 4
) 30 parts organic bentonite (same as formulation 4) 2.7 Silane coupling agent (same as formulation 4) 0.1 Styrene 16 Cobalt naphthenate (same as formulation 4) 0.7 Conductive white pigment 50 (hardening agent) Methyl ethyl ketone peroxide 0.7 The conductive white pigment is manufactured by Mitsubishi Metals under the trade name W-1.
[A conductive film of tin oxide and antimony oxide was formed on the surface of fine titanium oxide powder] was used. [Formulation 9] (Main ingredient) Epoxy acrylate resin (same as formulation 5) 30 parts Organic bentonite (same as formulation 4) 2.7 Silane coupling agent (same as formulation 5) 0.2 Styrene 11.2 Cobalt naphthenate (same as formulation 4) 0.7 Conductive white pigment (same as formulation 8) 54 (curing agent) Methyl ethyl ketone peroxide 1.2 [Formulation 10] (base ingredient) Epoxy resin (same as formulation 3) 15 Organic bentonite (same as formulation 4) 1 Xylol 18 Methyl isobutyl ketone 5 Titanium coupling agent 1 Conductive white pigment 60 (Curing agent) Polyamide resin (same as formulation 3) 10 Xylol 27 Isobutanol 13 The titanium coupling agent is manufactured by Ajinomoto Co., Inc. under the trade name Prene Act KR-2S [isopropyl octanoyl titanate] ], the conductive white pigment is titanium oxide [trade name KA-30 manufactured by Titan Industries Co., Ltd.] and transparent conductive metal oxide [trade name T-1 manufactured by Mitsubishi Metals Co., Ltd.: tin oxide and antimony oxide. mixture] 3:1 (weight ratio)
A mixture of these in the following proportions was used. [Formulation 11] (Base ingredient) Isophthalic acid-based unsaturated polyester resin (Formulation 4
24 parts organic bennite (same as formulation 4) 2.7 Silane coupling agent (same as formulation 4) 1 Styrene 11 Cobalt naphthenate (same as formulation 4) 0.7 Conductive white pigment (same as formulation 8) 60 (cured) agent) Methyl ethyl ketone peroxide 0.6 [Formulation 12] (Main agent) Isophthalic acid-based unsaturated polyester resin (Formulation 4
) 26 parts organic bentonite (same as formulation 4) 2.7 Titanium coupling agent 2 Styrene 13 Cobalt naphthenate (same as formulation 4) 0.7 Conductive white pigment (same as formulation 8) 55 (hardening agent) Methyl ethyl ketone peroxide 0.6 The titanium coupling agent is manufactured by Ajinomoto Co., Inc. under the trade name Prene Act KR-38S [isopropyl tris (dioctyl pyrophosphate) titanate].
It was used. [Formulation 13] (Main ingredient) Epoxy resin (same as formulation 3) 30 parts Organic bentonite (same as formulation 4) 1 Xylol 19 Methyl isobutyl ketone 5 Carbon black 5 Talc 40 (Curing agent) Polyamide resin (same as formulation 3) 20 Xylol 20 Isobutanol 10 The above formulations 8 to 13 are room temperature curable resin compositions, and each component of the main ingredient was kneaded in a kneader, and then a curing agent was mixed at the time of use. Example 1 After completely removing black scale, rust, and oil from a 150 x 150 x 0.6 mm mild steel plate (JIS-G-3141) by shot blasting, the above composition was air-sprayed to a dry film thickness of 40±. Painted to a thickness of 5 microns, heated at 20℃,
A zinc-rich paint film was obtained by drying at 75% RH for 7 days. Next, Formulation 4 was applied on top of it to a dry film thickness of 500±50 microns, and after drying at room temperature for 7 days, Formulation 8 was applied to a dry film thickness of 50±5 microns and dried for 7 days. Finished by drying at room temperature. Example 2 Formulation 2 was coated on the same substrate as in Example 1 to give a dry film thickness of 40±5 microns, and after drying, Formulation 5 was applied in the same manner and allowed to dry. Then,
Formulation 9 was applied so that the dry film thickness was 100±10 microns, and after drying, it was similarly subjected to a comparative test. Example 3 Formulation 3 was applied onto the same substrate as in Example 1, and after drying, Formulation 6 was applied in the same manner. Then mix
No. 10 was applied to give a dry film thickness of 50±5 microns, and after drying, it was subjected to a comparative test. Example 4 Formulation 1 was applied onto the same substrate as in Example 1, dried, and then applied twice with Formulation 7 so that the dry film thickness in each application was 150±20 microns. It was dried for 7 days. However, the second coat was applied 24 hours after the first coat. Next, Formulation 11 was applied and dried in the same manner as described above, and then subjected to a comparative test. Example 5 Formulation 2 was applied onto the same substrate as in Example 1 and dried, and then Formulation 7 was applied and dried in the same manner as in Example 4. Next, Formulation 12 was applied and dried in the same manner as described above, and then subjected to a comparative test. Comparative Example 1 Formulation 1 was applied in the same manner as in Example 1 on the same substrate as in Example 1, and after drying, Formulation 4 was applied to the coating material with a dry film thickness.
It was applied to a thickness of 550±50 microns, dried in the same manner, and then subjected to a comparative test. Comparative Example 2 Formulation 2 was applied on the same substrate as in Example 1 and dried in the same manner as in Example 2, and then Formulation 5 was applied in the same manner as in Comparative Example 1, and after drying, it was subjected to a comparative test. Comparative Example 3 On the same substrate as in Example 1, Formulation 3 was applied and dried in the same manner as in Example 3, and then Formulation 6 was applied in the same manner as in Comparative Example 1, and after drying, it was subjected to a comparative test. . Comparative Example 4 Formulation 1 was applied and dried on the same substrate as in Example 1, and then Formulation 7 was applied twice so that the dry film thickness in each application was 170 ± 20 microns. The coating was applied in the same manner as in Example 4, and after drying, it was subjected to a comparative test. Comparative Example 5 Formulation 1 was applied onto the same object as in Example 1 and dried, and Formulation 4 was similarly applied and dried.
Formulation 13 was then applied in the same manner and after drying was subjected to a comparative test.

【table】

【table】

[Table] It is clear from the above comparative test results that the film obtained by the finishing method of the present invention had both rust prevention properties and a resistance value sufficient to eliminate static electricity. On the other hand, the films obtained in Comparative Examples 1 to 4 had high resistance values and were insufficient for removing static electricity, and the film obtained in Comparative Example 5 had significantly poor rust prevention properties. A product having both properties could not be obtained.

Claims (1)

[Claims] 1 () The thickness of a dry coating film for steel structures
A process of applying zinc-rich paint to a thickness of 10 to 70 microns and drying, () A process of applying an intermediate coat on the zinc-rich paint and drying, and () A process of applying resin on the intermediate coat. Applying a room-temperature curable resin composition in which 80 to 400 parts by weight of a conductive white pigment, 0.01 to 5.0 parts by weight of a silane coupling agent, or 0.01 to 10.0 parts by weight of a titanium coupling agent are added to 100 parts by weight of the components, A rust-proof coating finishing method consisting of a drying process. 2. Zinc-rich paint uses epoxy resin, ethyl silicate, potassium silicate, or lithium silicate as a binder, and contains 80 to 90% by weight of zinc dust in the dry coating film.Claim 1
Rust-preventive coating finishing method described in section. 3. The rust-preventive coating method according to claim 1, wherein the intermediate coating is an epoxy resin coating comprising an epoxy resin and a curing agent. 4. The rust-preventive coating finishing method according to claim 1, wherein the intermediate coating is a room temperature curable liquid coating composition comprising 10 to 60 parts by weight of a flat pigment to 100 parts by weight of a resin component. 5. The rust preventive coating finishing method according to claim 4, wherein the resin component of the intermediate coating is one or a mixture of two or more of liquid unsaturated polyester resins or epoxy resins. 6 Flat pigments have a thickness of 0.5 to 10 microns and a size
5. The rust-preventive coating finishing method according to claim 4, wherein the glass flakes are 0.3 to 6 mm. 7. The rust preventive coating finishing method according to claim 1, wherein the resin component in the room temperature curable resin composition is an unsaturated polyester resin and/or an epoxy resin. 8. The rust preventive according to claim 1, wherein the conductive white pigment is a pigment in which a film of a conductive metal oxide is formed on the surface of a white pigment, or a mixed pigment of a white pigment and a conductive metal oxide. Coating finishing method. 9 The silane coupling agent is one or a mixture of two or more of β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-methacryloxypropyltrimethoxysilane. A rust-proofing coating finishing method according to claim 1. 10 Titanium coupling agents are isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate)
Titanate, bis(dioctylpyrophosphate) oxyacetate titanate, bis(dioctylpyrophosphate) ethylene titanate,
Isopropyltrioctanoyltitanate, Isopropyldimethacrylisostearoyltitanate, Isopropylisostearoyldiacryltitanate, Isopropyltri(dioctylphosphate)titanate, Isopropyltricumylphenyltitanate, Isopropyltri(N-aminoethyl-aminoethyl)titanate, Dicumylf One or two of enyloxyacetate titanate and diisostearoyl ethylene titanate
The rust-preventive coating finishing method according to claim 1, which is a mixture of more than one species. 11 Conductive white pigment has In ₂ O ₃ on the surface of the white pigment,
The rust-preventive coating finishing method according to claim 1, wherein a film of SnO ₂ or Sb ₂ O ₃ is formed.