JP5631868B2 - Zinc-based black rust preventive agent, rust preventive film and rust preventive metal member - Google Patents

Description

  The present invention relates to a zinc-based black rust preventive agent, a rust preventive coating, and a rust preventive metal member. More specifically, the present invention relates to a rust preventive coating and an antirust coating excellent in rust prevention as a black rust preventive and having a sufficient black color tone. The present invention relates to a rust metal member and a zinc-based black rust inhibitor capable of forming the rust preventive film.

  As the metal anticorrosive paint, those containing a metal powder such as zinc pigment and aluminum powder which exhibit a sacrificial anticorrosive effect due to an ionization tendency larger than iron, for example, zinc rich paint are well known. There are two types of zinc rich paint, one that uses an organic solvent and the other that can be diluted with water. Zinc rich paints that use organic solvents include organic zinc rich paints that use organic resins such as epoxy resins as binders, and inorganic zinc rich paints that use inorganic binders such as ethyl silicate. Yes. Also known as water-based zinc rich paints are silicates typified by water glass or the like or chromic acid as a binder.

  In particular, zinc-rich paint containing chromic acid has a chromic acid component contained in the liquid that gives the coating a self-healing function and significantly improves the rust prevention performance due to the sacrificial anticorrosive effect of the rust prevention coating. It functions as an inhibitor that forms a stable film formation on the surface of zinc or aluminum particles blended in and prevents the reaction between the aqueous binder solution and the metal powder that generates hydrogen. Thus, the anticorrosion paint containing a chromic acid component is excellent in corrosion resistance in a thin film, and thus has been widely used for automobile bolts and nuts.

  However, from the viewpoint of environmental problems, there has recently been a demand for a non-chromium metal rust preventive paint that does not contain a chromic acid component, and a number of non-chromium metal rust preventive paints have been proposed.

  For example, Patent Document 1 discloses “a metal anticorrosive characterized by comprising a water-soluble synthetic resin binder, a fine metal powder having a higher ionization tendency than the metal to be treated, and an antioxidant for the metal”. (Claim 1).

  Patent Document 2 discloses that “one or more metal powders having a higher ionization tendency than the metal to be treated, a water-insoluble thermoplastic resin powder, a water-soluble rust preventive agent, a surfactant, and a thickening agent. A self-sacrificial metal anticorrosive characterized by comprising an agent and water (claim 1).

  Patent Document 3 states that “a zinc-powder-containing epoxy resin paint that is primed after degreasing and blasting an iron base, and the zinc-powder-containing epoxy resin paint is added to 10 parts by weight of a vehicle mainly composed of an epoxy resin. On the other hand, a coating material for iron base is described which is a composition containing 20 to 200 parts by weight of zinc powder and 0.05 to 0.5 parts by weight of thermally expandable powder (Claim 1). .

  Further, Patent Document 4 discloses a “water-diluted coating composition that does not contain chromium for applying to a substrate and then thermosetting the substrate to give corrosion protection to the substrate, together with an aqueous medium, Comprising (A) a high boiling organic liquid; (B) a particulate metal; (C) a thickener; and (D) a silane binder comprising from about 3 to about 20% by weight of the total composition weight. The coating composition "is described (claim 1).

  As for the anticorrosive agent containing much zinc like the metal anticorrosive agent etc. which were described in patent documents 1-4, what shows a silver color after coating is common.

  However, in recent years, depending on the use of a metal part or the like processed at a high temperature part such as around an automobile engine, a material exhibiting a black color is required. Parts around automobile engines and lower parts are black, and using bolts, nuts, etc. coated with zinc-based rust preventive agent makes silver color conspicuous, which is not preferable from the viewpoint of design. For this reason, at present, a black paint is applied as a top coat on top of the zinc-based rust preventive. However, if the top coat is used at this time, the number of processing steps increases, which is not preferable in terms of work. In addition, if the used top coat is scratched, the underlying silver color appears, which is not preferable.

  On the other hand, in order to improve the problem of showing a silver color, a method of blackening a rust preventive containing a large amount of zinc can be mentioned, for example, a method of blending carbon black.

  As a technique using carbon black as a blacking agent, for example, Patent Document 5 describes, “(B) Zinc powder 50 to 86 parts by weight and (C) with respect to 100 parts by weight of the coating film forming component containing resin (A)”. "Black zinc dust coating composition comprising 1 to 10 parts by weight of conductive carbon black" is described (Claim 1). However, as in the “black zinc dust coating composition” described in Patent Document 5, when a large amount of carbon black is blended, it is considered that a local battery is formed in the film by the carbon black, resulting in poor rust prevention. There is a problem that it ends up.

  In addition, when normal black iron oxide is blended with a zinc-containing anticorrosive agent, black iron oxide has a poor concealment rate for silver based on zinc, so when a thin film having a thickness of 5 to 10 μm is formed on a bolt or the like, for example In addition, sufficient black cannot be obtained, and depending on the attachment site, there is a defect that the color changes under severe conditions such as a high temperature to turn red, and a preferable black cannot be maintained for a long time.

JP 06-41472 A JP 2001-303279 A JP-A-10-68085 JP 10-46058 A JP 06-49393 A

  The present invention has been made under such a background, and a conventional metal substrate such as iron or steel is treated with a zinc-based rust inhibitor to form a film on the surface of the metal substrate. It was made for the purpose of overcoming the disadvantages of silver.

  That is, the present invention is excellent in rust resistance as a black rust preventive agent and has a sufficient black color tone, a rust preventive film and a rust preventive metal member, and a zinc-based black capable of forming the rust preventive film. It aims at providing a rust preventive agent.

  In view of the above problems, the present inventors have made various studies in order to develop a zinc-based black rust inhibitor having desirable characteristics. As a result, the present inventors have developed a zinc-based black anti-corrosion containing a specific component at a specific mass ratio. Rust agent and anti-rust coating were found, and this zinc-based black anti-corrosion agent and anti-rust coating, especially the anti-corrosion coating formed on the surface of metal substrates using this zinc-based black anti-corrosion agent, had excellent anti-rust properties. And the present inventors have found that the object can be achieved. Therefore, the present inventors have completed this invention based on this finding.

As means for solving the problems,
Claim 1 includes (1) a zinc pigment and / or a zinc alloy pigment, (2) black synthetic iron oxide, and (3) a phosphoric acid anticorrosive pigment. The mass ratio ((1) / (2)) between the pigment and the (2) black synthetic iron oxide is 85/15 to 65/35, the (2) black synthetic iron oxide and the (3) phosphoric acid-based rust preventive It is a zinc-based black rust inhibitor characterized by being contained so as to have a mass ratio to the pigment ((2) / (3)) of 70/30 to 50/50 and not containing carbon black ,
A second aspect of the present invention is the zinc-based black rust preventive agent according to the first aspect, comprising (4) a silane coupling agent and / or a titanium coupling agent, and (5) an alcohol-based solvent. ,
Claim 3 is (1) zinc pigment and / or zinc alloy pigment, (2) black synthetic iron oxide, and (3) phosphoric acid rust preventive pigment. The mass ratio ((1) / (2)) between the pigment and the (2) black synthetic iron oxide is 85/15 to 65/35, the (2) black synthetic iron oxide and the (3) phosphoric acid-based rust preventive It is a rust preventive film characterized in that it is contained so as to have a mass ratio with the pigment ((2) / (3)) of 70/30 to 50/50, and does not contain carbon black ,
A fourth aspect of the present invention is the rust preventive film according to the third aspect, characterized by containing (4) silicon oxide and / or titanium oxide.
Claim 5 is the rust preventive film according to claim 3 or 4, wherein the zinc-based black rust inhibitor according to claim 1 or 2 is dried at 70 to 120 ° C and baked at 250 to 360 ° C. ,
Claim 6 is a rust preventive metal member characterized by having the rust preventive film according to any one of claims 3 to 5 on the surface of a metal substrate.
A seventh aspect of the present invention is the rustproof metal member according to the sixth aspect, wherein the rustproof film has a thickness of 5 to 20 μm.

  Since the rust preventive film according to the present invention contains the specific constituent components at a specific mass ratio, the rust preventive metal member according to the present invention has the rust preventive film according to the present invention on its surface. Therefore, it can exhibit excellent rust prevention properties and exhibit a black color with excellent color. Since the zinc-based black rust preventive agent according to the present invention contains the specific constituent component at a specific mass ratio, when the anticorrosive film is formed, the zinc-based black rust preventive agent exhibits excellent rust preventive properties and has a tint. Excellent black color can be exhibited. Therefore, according to the present invention, the rust preventive film and the rust preventive metal member having excellent rust preventive properties as a black rust preventive agent and having a sufficient black color tone, and zinc capable of forming the rust preventive film are provided. System black rust preventive agent can be provided.

  The zinc-based black rust preventive agent according to the present invention comprises (1) a zinc pigment and / or a zinc alloy pigment, (2) black synthetic iron oxide, and (3) a phosphoric acid-based rust preventive pigment, which will be described later. It is contained so that it becomes. That is, the zinc-based black rust preventive agent according to the present invention will be described later with (1) a zinc pigment and / or a zinc alloy pigment, (2) black synthetic iron oxide, and (3) a phosphoric acid-based rust preventive pigment. It can also be called the composition to contain so that it may become mass ratio.

  The (1) zinc pigment and / or zinc alloy pigment may be a pulverized product, crushed product, particulate product, or the like of zinc and / or zinc alloy. For example, zinc and / or zinc alloy powder, zinc and / or Or the zinc alloy flake particle | grains etc. are mentioned. Examples of the metal other than zinc forming the zinc alloy include aluminum, tin, magnesium, nickel, cobalt, manganese and the like. As the zinc alloy, a zinc alloy of zinc and aluminum, an alloy of zinc and tin, an alloy of zinc, aluminum and tin, or the like is preferable. It is preferable that the zinc content in the zinc alloy is more than 50% by mass in terms of excellent rust prevention performance of the formed rust prevention film. For example, in the zinc alloy of zinc and aluminum, the zinc content is more preferably 80% by mass or more, and particularly preferably 85% by mass or more. In the zinc alloy of zinc and tin, the zinc content is more preferably 70% by mass or more, and particularly preferably 80% by mass or more.

  The shape of the zinc pigment and zinc alloy pigment is not particularly limited, but is preferably flake particles. That is, preferred examples of the zinc pigment and / or zinc alloy pigment include zinc flakes, zinc alloy flakes of zinc and aluminum, and zinc alloy flakes of zinc and tin. When zinc pigments and / or zinc alloy pigments are used as flake particles, it is preferred that at least 50% by weight flake particles out of the total mass have a major axis of less than about 25 μm, and at least 90% by weight flake particles are about 20 μm. It is preferable to have a major axis of less than. The thickness of the flakes is preferably about 0.05 to 1 μm, and preferably about 0.1 to 0.5 μm. The major axis of the flakes can be measured by a laser diffraction / scattering particle size distribution analyzer, and the thickness thereof can be measured by an electron microscope of the section.

  Zinc pigments and / or zinc alloy pigments, for example, made into a paste with a solvent contained in a zinc-based black rust preventive agent, do not powder, and dispersibility in the zinc-based black rust preventive agent is higher. From the point of view, it is preferable.

  The zinc pigment and / or zinc alloy pigment preferably has a high purity, and may actually have a purity of 99% by mass or more.

Wherein (2) black synthetic iron oxide may be a heat-resistant synthetic iron oxide exhibiting black color, for example, be a mole fraction of _{(FeO) x- (Fe 2 O} 3) y (x is (FeO) , Y is a molar fraction of (Fe ₂ O ₃ ), and x + y is 1.), and triiron tetroxide or a hydrate thereof. The triiron tetroxide is also described as Fe ₃ O _4, which is a cubic crystal of an inverted spinel lattice, oxygen is arranged at the apex of the cubic lattice, and Fe ²⁺ ions remain at the half of the octahedral apex centering on oxygen. Fe ³⁺ ions are arranged on half of the octahedron apex and tetrahedron apex. Both FeO and γ-Fe ₂ O ₃ have the same cubic arrangement of oxygen. These three compounds easily change from each other by an oxidation reaction or a reduction reaction, but the difference in the final structure is small. Depending on the sample, Fe ₃ O ₄ may be a non-stoichiometric compound. The shape or the like of the black synthetic iron oxide is not particularly limited, and examples thereof include a spherical shape, an octahedral shape, a powder shape, a flake shape, and the like, and the average particle size thereof is not particularly limited.

  As black synthetic iron oxide, for example, trade name “ETB-300 (TAROX synthetic iron oxide)” (made by Titanium Industry Co., Ltd.), trade name “BL-100, BL-500 etc.” (made by Titanium Industry Co., Ltd.), etc. Can be easily obtained.

  Examples of (3) phosphate-based anticorrosive pigments include zinc phosphate, basic zinc phosphate, zinc polyphosphate, ortho-zinc zinc phosphate, calcium zinc phosphate, magnesium zinc phosphate, magnesium phosphate, phosphorous acid Examples include zinc, zinc phosphomolybdate, aluminum tripolyphosphate, aluminum phosphite, and calcium phosphite. Of these, zinc phosphate, zinc polyphosphate, aluminum phosphate and the like are preferable from the viewpoint of availability.

  Examples of the phosphoric acid-based rust preventive pigment include, for example, the trade name “rust preventive pigment K-white # 82, # 84, # 84S, # 85, # 94, # 105” (manufactured by Teika Co., Ltd.) Pigments ZP-DL, P-WF, P-W-2, D-1, ZP-50S, ZP-SB, ZP-HS, MZP-500, MP-620PMG, ZP-600 "(manufactured by Kikuchi Color Co., Ltd.) And trade names “EXPERT NP-530, NP-1530, NP-1020, NP-1102” (manufactured by Toho Pigment Co., Ltd.).

  In addition to the (1) zinc pigment and / or zinc alloy pigment, the (2) black synthetic iron oxide, and the (3) phosphoric acid-based rust preventive pigment according to the present invention, If desired, it may contain (4) a silane coupling agent and / or a titanium coupling agent, (5) an alcohol solvent, and other components.

  As said (4) silane coupling agent and / or titanium coupling agent, the coupling agent shown by following General formula (1) is mentioned, for example.

General formula (1): (R < ¹ >) _m- Met- (OR < ² >) _4-m
(Here, in General Formula (1), Met is a Si atom or a Ti atom, and R ¹ and R ² are each a branched chain having 1 to 8 carbon atoms which may have the same or different substituents, or A straight-chain hydrocarbon group, m is an integer of 0 to 3.)

As the silane coupling agent, the following general formula (2): (R ¹ ) _m -Si- (OR ² ) _4-m (wherein R ¹ , R ² and m in the general formula (2) The same as R ¹ , R ² and m in the general formula (1).), More specifically, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, Tetraisopropoxysilane, tetra-n-butoxysilane, tetra-iso-butoxysilane, tetra-sec-butoxysilane, tetra-t-butoxysilane, pentyltriethoxysilane, trimethoxymethylsilane, trimethoxy (methyl) silane, tri Ethoxyethylsilane, trimethoxy (propyl) silane, monoethoxytrimethoxysilane, monobutoxytrimethoxysila , Monopentoxytrimethoxysilane, monohexoxytrimethoxysilane, dimethoxydiethoxysilane, dimethoxydibutoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, γ-glycidoxypropyltrimethoxy Examples include silane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, and the like.

  Preferred examples of the silane coupling agent include tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, γ-glycidoxypropylmethyldimethoxysilane, and γ-glycidoxytrimethoxysilane.

  In this invention, as the silane coupling agent, in addition to or instead of the monomer represented by the general formula (2), one or more of the monomers may be polycondensed. The polycondensate obtained in this way can be used.

As the titanium coupling agent, the following general formula (3): (R ¹ ) _m -Ti- (OR ² ) _4-m (wherein R ¹ , R ² and m in the general formula (3) The same as R ¹ , R ² and m in the general formula (1).), And more specifically, tetramethoxy titanium, tetrapropoxy titanium, tetra-iso-propoxy titanium, Tetrabutoxytitanium, tetrakis (2-ethylhexyloxy) titanium, titanium-iso-propoxyoctylene glycolate, propanedioxytitanium bis (ethylacetoacetonate) and the like can be mentioned.

  Among these, preferable examples of the titanium coupling agent include tetramethoxy titanium, tetrapropoxy titanium, tetra-iso-propoxy titanium, and tetrabutoxy titanium.

  In this invention, as the titanium coupling agent, in addition to or instead of the monomer represented by the general formula (3), one or more of the monomers may be polycondensed. The polycondensate obtained in this way can be used.

  As said (5) alcohol solvent, the organic solvent arbitrarily mixed with water is preferable and monohydric or polyhydric alcohol which has a C1-C8 linear or branched hydrocarbon group is mentioned. Such alcohols preferably include mono- or polyhydric alcohols having 2 to 4 carbon atoms, polyhydric alcohol ethers and polyhydric alcohol esters.

  As the alcohol solvent, at least one solvent selected from the group consisting of monohydric alcohols, polyhydric alcohols, polyhydric alcohol ethers, and polyhydric alcohol esters is preferably used. Examples of the monohydric alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol and the like. Examples of the polyhydric alcohol include glycol, glycerin, propylene glycol, diglycol, diglycerin, dipropylene glycol, triglycol, tripropylene glycol, and butylene glycol. Examples of the ethers of the polyhydric alcohol include monoalkyl ethers of the polyhydric alcohol. Specifically, the monoalkyl ether includes ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono Propyl butyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl thiol ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl butyl ether, propylene glycol monobutyl ether , Dipropylene glycol monomethyl Ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl chill ether, dipropylene glycol monobutyl ether. Examples of the polyhydric alcohol esters include mono short-chain fatty acid esters of the polyhydric alcohol. Specifically, the mono short-chain fatty acid esters include ethylene glycol monoacetate and diethylene glycol monoacetate. Examples include ethylene glycol monoacetate, propylene glycol monoacetate, ethylene glycol monoacetate, and dipropylene glycol monoacetate.

  As said other component, the various additives normally mix | blended with a coating material are mentioned. Examples of the various additives include surfactants, thickeners, antifoaming agents, dispersants, colorants, extender pigments, and lubricants. The surfactant only needs to be able to disperse the components to be blended, and examples thereof include ionic and nonionic active agents. Examples of the thickener include hydroxyethyl cellulose, methyl cellulose, methyl hydroxypropyl cellulose, ethyl hydroxyethyl cellulose, methyl ethyl cellulose, xanthan gum and the like. When the zinc-based black rust preventive agent according to the present invention contains a thickener, the viscosity of the zinc-based black rust preventive agent can be maintained at an appropriate viscosity, and the coating amount at the time of application can be maintained moderately. . The zinc-based black rust preventive according to the present invention is substantially free of chromium, for example, hexavalent chromium.

  The zinc-based black rust preventive agent according to the present invention may contain a solvent other than alcohol, and if the zinc-based black rust preventive agent contains the solvent, workability and the like are improved. Examples of the solvent include organic solvents other than the alcohol solvent (5), water, and the like, but the solvent is preferably water from the viewpoint of contamination into the air during drying. The water is not particularly limited, for example, but water having a small content of impurities such as purified water and deionized water is preferable.

  The zinc-based black rust preventive agent according to the present invention is a specific example of (1) zinc pigment and / or zinc alloy pigment, (2) black synthetic iron oxide, and (3) phosphoric acid-based rust preventive pigment. Contains by mass ratio. That is, the mass ratio ((1) / (2)) of the (1) zinc pigment and / or zinc alloy pigment to the (2) black synthetic iron oxide is 85/15 to 65/35, ) The mass ratio ((2) / (3)) of the black synthetic iron oxide to the (3) phosphoric acid anticorrosive pigment is 70/30 to 50/50.

  The mass ratio ((1) / (2)) between the (1) zinc pigment and / or zinc alloy pigment and the (2) black synthetic iron oxide is 85/15. (1) The zinc pigment and / or zinc alloy When the mass ratio of the pigment is increased, the mass ratio of the (2) black synthetic iron oxide is relatively decreased, and the obtained rust preventive film may exhibit a light black color. On the other hand, when the mass ratio ((1) / (2)) is less than 65/35 and the mass ratio of the (1) zinc pigment and / or zinc alloy pigment is reduced, the rust prevention performance of the resulting rust preventive coating is lowered. Sometimes.

  The mass ratio ((1) / (2)) is 85/15 to 75/25 in that the obtained rust preventive film exhibits a more excellent black color and exhibits a higher rust prevention performance. Preferably there is.

  The mass ratio of (2) black synthetic iron oxide to (2) black synthetic iron oxide is larger than the mass ratio ((2) / (3)) of (2) black synthetic iron oxide to (3) phosphoric acid-based anticorrosive pigment. If it becomes, the antirust performance of the obtained antirust film may fall. On the other hand, when the mass ratio ((2) / (3)) is less than 50/50 and the mass ratio of the (2) black synthetic iron oxide is small, the resulting rust-preventive coating may exhibit a light black color. is there.

  The mass ratio ((2) / (3)) is 70/30 to 60/40 in that the obtained rust preventive film exhibits a more excellent black color and exhibits higher rust prevention performance. Is preferred.

  Thus, in the zinc-based black rust inhibitor according to the present invention, when the mass ratio ((1) / (2)) and the mass ratio ((2) / (3)) are both within the above range. The obtained anticorrosion film exhibits a black color with excellent color and exhibits high antirust performance.

  In the zinc-based black rust preventive agent according to the present invention, when the (4) silane coupling agent is optionally contained, the content of the silane coupling agent is the total mass of the zinc-based black rust preventive agent. Is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and particularly preferably 3 to 15% by mass. When the content of the silane coupling agent is within the above range, the resulting antirust coating can exhibit high film properties and corrosion resistance.

  Moreover, in the zinc-based black rust preventive agent according to the present invention, when the (4) titanium coupling agent is contained as desired, the content of the titanium coupling agent is that of the zinc-based black rust preventive agent. When the total mass is 100% by mass, it is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and particularly preferably 3 to 15% by mass. When the content of the titanium coupling agent is within the above range, the obtained rust preventive film can exhibit high film properties and corrosion resistance.

  When the silane coupling agent and the titanium coupling agent are optionally contained in the zinc-based black rust preventive agent according to the present invention, the respective content ratios may be within the above range, and the silane coupling agent The total content of the titanium coupling agent is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and particularly preferably 3 to 15% by mass.

  In the zinc-based black rust preventive agent according to the present invention, when the (5) alcohol-based solvent is optionally contained, the content of the alcohol-based solvent is 100% of the total mass of the zinc-based black rust preventive agent. When it is defined as mass%, it is preferably about 0.1 to 20 mass%. When the content of the alcohol solvent is within the above range, the zinc-based black rust preventive agent according to the present invention is applied, and in the process of forming a rust preventive film by drying and baking, it shows a remarkable effect on uniform film formation. .

  In the zinc-based black rust preventive agent according to the present invention, when the other components are contained as desired, the zinc-based black rust preventive agent is appropriately adjusted according to each component so as to obtain a content rate that is usually blended in the paint. The For example, in the zinc-based black rust preventive agent according to the present invention, when the surfactant is optionally contained, the content of the surfactant is 100 masses of the total mass of the zinc-based black rust preventive agent. % Is preferably about 0.1 to 10% by mass. Moreover, in the zinc-based black rust preventive agent according to the present invention, when the thickener is optionally contained, the content of the thickener is 100 masses of the total mass of the zinc-based black rust preventive agent. %, It is preferably about 0.1 to 2.0% by mass. When the content of the thickener is within the above range, the viscosity of the zinc-based black rust preventive agent can be maintained at an appropriate viscosity, and the application amount at the time of application can be maintained appropriately.

  In the zinc-based black rust preventive agent according to the present invention, when the solvent is contained as desired, the zinc-based black rust preventive agent has the storage stability of the zinc-based black rust preventive agent, the handling property, etc. The total mass of the (1) zinc pigment and / or zinc alloy pigment, the (2) black synthetic iron oxide and the (3) phosphoric acid-based anticorrosive pigment is 20 to 50% by mass with respect to the total mass. In addition, the content of the solvent is preferably adjusted.

  The zinc-based black rust inhibitor according to the present invention can be produced in the same manner as a normal paint. For example, the components described above can be produced by mixing them with a mixer at the specific mass ratio. When the zinc-based black rust preventive agent according to the present invention contains the (5) alcohol solvent and / or the solvent, the components described above are dispersed in these solvents at the specific mass ratio. Can be manufactured. The (5) alcohol-based solvent or a component that is relatively difficult to disperse in the solvent is prepared by dispersing it in advance in a small amount of dispersion medium at a high concentration and further blending it finally. Can do.

  For example, the zinc-based black rust preventive agent according to the present invention is applied to the surface of a metal substrate, and then dried and baked to form a rust preventive coating. That is, the rust preventive film according to the present invention is obtained by drying and baking the zinc-based black rust preventive agent according to the present invention.

  Examples of the metal substrate include metal molded products such as iron and steel. As long as these metal molded articles have a surface to which the zinc-based black rust preventive agent according to the present invention is applied, the shape thereof is not particularly limited. As said metal molded product, the metal molded product for motor vehicles, the metal molded product for civil engineering, etc. are mentioned, for example. Specific examples of metal molded products for automobiles include various plate-shaped molded products, fasteners such as screws, bolts, nuts, washers, and the like. Examples thereof include fasteners such as screws, bolts, nuts, washers and the like used for plate-shaped products, trains, and the like.

  Before applying the zinc-based black rust preventive agent according to the present invention, the metal member is pre-treated as a degreasing step for degreasing with a solvent, and a surface treatment step for roughening with a shot blasting material to improve adhesion. Further, a blasting process for scaling down may be appropriately performed. The degreasing process, the surface treatment process, the blasting process, and the like can employ conditions and methods that are usually performed.

In order to form the rust preventive film according to the present invention, the zinc-based black rust preventive agent according to the present invention is applied to the surface of the metal base material on which the pretreatment has been performed if desired. The application process of the zinc-based black rust inhibitor is usually carried out 1 to 3 times, for example, by a dip method, a spin method, a spray method, or the like. In this way, the zinc-based black rust inhibitor is, for example, so that the film thickness after baking is 5 to 20 μm, in other words, the content of the additive in the zinc-based black rust inhibitor, etc. However, the solid content based on (1) zinc pigment and / or zinc alloy pigment, (2) black synthetic iron oxide, (3) phosphoric acid anticorrosive pigment, etc. is 5 to 35 g / m ² (50 to 350 mg / m It is applied so as to have an adhesion amount of about dm ² ).

  In order to form the rust preventive film according to the present invention, the applied zinc-based black rust preventive is then dried at 70 to 120 ° C., for example, for 10 to 20 minutes. When the zinc-based black rust inhibitor is dried, the (5) alcohol-based solvent and / or the solvent contained in the zinc-based black rust inhibitor as desired is removed, and a coating film is formed. The drying process of the zinc-based black rust inhibitor is carried out using a heater, a dryer, or the like that is usually used.

  In order to form the rust preventive film according to the present invention, the dried coated film is then baked at 250 to 360 ° C, preferably 300 to 355 ° C. The baking process of a coating film is implemented over 20 minutes-2 hours, for example, Preferably it is 30 minutes-40 minutes. Thus, when the said coating film is baked, the antirust coating based on this invention is formed.

  In this way, the anticorrosive film according to the present invention can be formed on the surface of the metal substrate. In the present invention, if desired, the coating process, the drying process and the baking process are performed as a set, a plurality of times, for example, twice or three times, to form a multi-layered rust-preventing film formed by laminating a plurality of layers. You can also.

  The anticorrosive film according to the present invention thus formed comprises (1) a zinc pigment and / or a zinc alloy pigment, (2) black synthetic iron oxide, and (3) a phosphoric acid anticorrosive pigment. The mass ratio ((1) / (2)) of the (1) zinc pigment and / or zinc alloy pigment to the (2) black synthetic iron oxide is 85/15 to 65/35, and (2) It is contained so that the mass ratio ((2) / (3)) between the black synthetic iron oxide and the (3) phosphoric acid anticorrosive pigment is 70/30 to 50/50. In the rust preventive coating according to the present invention, the (1) zinc pigment and / or zinc alloy pigment, the (2) black synthetic iron oxide and the (3) phosphoric acid rust preventive pigment are the zinc black It is basically the same as the rust inhibitor. The preferable ranges of the mass ratio ((1) / (2)) and the mass ratio ((2) / (3)) are basically the same as those of the zinc-based black rust preventive according to the present invention. Therefore, the rust preventive film according to the present invention is excellent in rust preventiveness as a black rust preventive agent and has a sufficient black color tone.

  Specifically, the anticorrosive film according to the present invention is 750 hours or more, preferably 1000 hours or more before red rust is generated in the “salt spray test” described in JIS K 5600-7-1: 1999. Exhibits rust prevention. Moreover, the rust preventive film according to the present invention specifically has an L value smaller than 50 in “black color” described in JIS K 5600-4-6: 1999.

  In the rust preventive coating according to the present invention, silicon oxide and / or oxidation derived from the (4) silane coupling agent and / or titanium coupling agent optionally contained in the zinc-based black rust preventive according to the present invention. It contains titanium and other additives as described above.

  In the rust preventive coating according to the present invention, each of the silicon oxide and / or titanium oxide content is preferably 1 to 30% by mass when the total mass of the rust preventive coating is 100% by mass, It is more preferably 2 to 20% by mass, and particularly preferably 3 to 15% by mass. When the content of the silicon oxide and / or titanium oxide is within the above range, the obtained rust preventive film can exhibit high film properties and corrosion resistance. In addition, it is preferable that the total content rate of the said silicon oxide and a titanium oxide is 1-30 mass%, It is more preferable that it is 2-20 mass%, It is especially preferable that it is 3-15 mass%.

  As described above, the anticorrosive film formed as described above is adjusted to an appropriate thickness according to the type of the metal base material, the use of the metal base material, etc. Since it exhibits a black color with excellent taste and exhibits high antirust performance, it can be formed into a thin film. For example, the rust preventive film according to the present invention can be adjusted to a thickness of 5 to 20 μm, preferably 5 to 15 μm. Therefore, according to the present invention, even if the metal base is a member in which two or more members are engaged or locked, such as the fastener, the fastener is rust-proof and colored without impairing a predetermined fastening state. Black with excellent taste can be imparted.

  The rust preventive metal member according to the present invention has the rust preventive coating formed by baking the zinc-based black rust preventive agent according to the present invention on the surface of the metal base as described above. Therefore, the zinc-based black rust preventive agent according to the present invention is excellent in high rust-preventing property and color tone on the metal substrate without forming a black base coat layer and / or a black base coat layer. Black color can be imparted. Therefore, the rust preventive metal member according to the present invention is excellent in rust prevention as a black rust preventive and has a sufficient black color tone. Examples of the rust-proof metal member according to the present invention include metal molded products for automobiles and metal molded products for civil engineering and construction. Specific examples of metal molded products for automobiles include various plate-shaped molded products, fasteners such as screws, bolts, nuts, washers, and the like. Examples thereof include fasteners such as screws, bolts, nuts, washers and the like used for plate-shaped products, trains, and the like.

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

The following metal substrate samples 1 and 2 were prepared as metal substrates.
(1) Metal substrate sample 1: SPCC, 5D steel plate, size 70 × 150 × 0.8 mm
(2) Metal substrate sample 2: Bolt (made of mild steel), M10 × 55, screw pitch 1.5 mm, hardness 9T

Example 1
Each of the metal substrate samples 1 and 2 was separately degreased with a solvent, and then the surface was polished by blasting to complete the pretreatment of each sample.

  (4) 13.5 parts by mass of γ-glycidoxypropylmethoxysilane (manufactured by Chisso Corporation) as a silane coupling agent while stirring in 34.6 parts by mass of deionized water (8.00 μS / cm or less) S510) was blended and mixed. After stirring these for 3 hours, 0.8 parts by mass of orthoboric acid (manufactured by Wako Pure Chemical Industries, Ltd.) and 1.0 part by mass of a nonionic surfactant (HLB9.5) were further added to the mixture as other components. (NOF Corporation: Nonion NS-204.5), 1.0 part by mass of a nonionic surfactant (HLB13.5) (NOF Corporation: Nonion NS-208.5), and other additives A subtotal of 7.9 parts by mass of an appropriate amount of an antifoaming additive such as an antifoaming agent was added and stirred. To this mixture, (1) 11.4 parts by mass of dipropylene glycol (Asahi Glass Co., Ltd., abbreviated as DPG) was added as an alcoholic solvent. In addition to this mixture, 22.0 parts by mass of zinc pigment (manufactured by Mitsui Kinzoku Mining Co., Ltd.), 7.4 parts by mass of black synthetic iron oxide (manufactured by Titanium Industry Co., Ltd .: TAROX ETB-300), phosphoric acid-based anticorrosive pigment 3.2 parts by mass of zinc polyphosphate (Kikuchi Color Co., Ltd .: ZP-SB) was added. Then, using a dissolver type stirring device, all these components were thoroughly stirred over about 3 hours. In this way, a zinc-based black rust inhibitor was prepared.

The zinc pigment (manufactured by Mitsui Mining & Smelting Co., Ltd.) made zinc dust produced by a distillation method into flakes having a thickness of 0.1 to 0.8 μm (average of about 0.3 μm) and a major axis size of 10 to 20 μm. Is. Further, the black synthetic iron oxide (manufactured by Titanium Industry Co., Ltd .: ETB-300) has a particle size of 0.1 to 0.4 μm (manufacturer catalog value) and a specific surface area of 4 to 8 mg ² / g (manufacturer catalog value). It was.

  The pre-treated metal substrate sample 1 is coated with the zinc-based black rust inhibitor prepared as described above using a bar coater (No. 10) and dried at 100 ° C. for a predetermined time (10 minutes). And then baked at 330 ° C. for a predetermined time (30 minutes). This coating process, drying process, and baking process were repeated twice, so that the final film thickness was 5 to 10 μm. Thus, the rust-proof metal base material sample 1 in which the rust-proof film was formed was manufactured. In addition, as a result of measuring the thickness of the film with an electromagnetic film thickness meter, it was 7.1 μm.

On the other hand, five of the metal base sample 2 that has been subjected to the pretreatment are immersed in the zinc-based black rust preventive agent, and the zinc-based black rust preventive agent is finally applied to the surface of the metal base sample 2. The coating amount was 220 to 260 mg / dm ² as a target, dried at 100 ° C. for a predetermined time (10 minutes), and then baked at 330 ° C. for a predetermined time (30 minutes). This was repeated twice. In this way, five rust-proof metal substrate samples 2 on which a rust-proof film was formed were produced. The average coating amount in these rust-proof metal substrate samples 2 was 230 mg / dm ² . The coating amount (mg / dm ² ) is a value calculated from {(sample weight after treatment) − (weight before sample treatment)} / (area of sample). (Note that the area of the M10 bolt was based on the bolt manufacturer's calculation method, and an average value of 23.6 dm ² was used.

(Examples 2-9)
Except having changed into the composition shown in Table 1, it carried out similarly to Example 1, and manufactured the antirust metal base material sample 1 and the five antirust metal base material samples 2, respectively.

(Comparative Examples 1-35)
Except having changed into the composition shown in Tables 2-4, it carried out similarly to Example 1, and manufactured the antirust metal base material sample 1 and the five antirust metal base material samples 2, respectively.

  In this way, each component of the “rust preventive coating” in the rust preventive metal substrate sample 1 obtained in Examples 1 to 9 and Comparative Examples 1 to 35 was quantified by fluorescent X-ray analysis. From this measurement result, the mass ratio (1) / (2) and the mass ratio (2) / (3) in the “rust preventive coating” were calculated. Moreover, the thickness of the antirust coating in the antirust metal substrate sample 1 was measured with an electromagnetic film pressure gauge (Fischer). The coating amount in the rust-proof metal substrate sample 2 was calculated by the above formula. In Tables 2 to 4, when the component (2) or (3) is not contained, the mass ratio (1) / (2) or the mass ratio (2) / (3) is set to “100 / "0". These results are shown in Tables 1 to 4 together with the measurement results.

  The “black tint” by the rust-proof metal substrate sample 1 obtained in Examples 1 to 9 and Comparative Examples 1 to 35, respectively, and the “salt spray test” in the rust-proof metal substrate sample 2 are as follows. It implemented like this and evaluated comprehensively.

A black color test as a black tone is described in JIS K 5600-4-6 (1999) using a metal substrate sample 1 on which a rust-proof coating having a thickness of 5 to 10 μm is formed. Furthermore, the L value in “black color” (hue measurement) was used. The color difference meter used was a model number “CR-300” manufactured by Minolta. The measured L value is evaluated in four stages and is shown in Table 1 with symbols.
◎: L value is less than 10 ○: L value is 10 or more and less than 40 Δ: L value is 40 or more and less than 50 ×: L value is 50 or more

The salt spray test as rust prevention performance was carried out in accordance with the “salt spray test” described in JIS K 5600-7-1: 1999. The time until red rust occurs is measured, and the time is evaluated in four stages.
◎: Red rust generated at 1000 hours to 1500 hours; Red rust generated at 750 hours to less than 1000 hours Δ; Red rust generated at 500 hours to less than 750 hours x; Red rust generated at less than 500 hours

Based on the “black color” and the “salt spray test” evaluated in this way, the results of comprehensive evaluation according to the following criteria are shown in Table 1 with symbols.
◎: When the evaluation of the salt spray test is ◎ and the evaluation of the black color test is △ or more ○: When the evaluation of the salt water test is ◯ and the evaluation of the black color test is △: Salt spray When there is at least x in the evaluation of the test or the evaluation of the black color test, or the evaluation of the salt spray test or the evaluation of the black color test is Δ

  The results of the salt spray test thus obtained are as follows: (1) the mass ratio ((1) / (2)) of the zinc pigment and / or zinc alloy pigment to the (2) black synthetic iron oxide; Table 5 summarizes the mass ratio ((2) / (3)) between (2) black synthetic iron oxide and the (3) phosphoric acid anticorrosive pigment.

  Moreover, the result of the obtained black color test is the mass ratio ((1) / (2)) of the (1) zinc pigment and / or zinc alloy pigment and the (2) black synthetic iron oxide, Table 2 summarizes the mass ratio ((2) / (3)) between (2) black synthetic iron oxide and (3) the phosphoric acid-based anticorrosive pigment.

  As shown in Table 1, Table 5, and Table 6, Examples 1 to 9 containing specific components at a specific mass ratio were all excellent in rust prevention performance and black color test.

  On the other hand, as shown in Tables 2 to 6, Comparative Examples 1 to 35 that do not contain a specific component or that contain a specific component are outside the range of a specific mass ratio, In either case, at least one of rust prevention performance or black tone was insufficient. Further, Comparative Example 35 using carbon black instead of black synthetic iron oxide had insufficient rust prevention performance.

Claims (7)

(1) a zinc pigment and / or a zinc alloy pigment, (2) black synthetic iron oxide, and (3) a phosphoric acid anticorrosive pigment.
The mass ratio ((1) / (2)) of the (1) zinc pigment and / or zinc alloy pigment to the (2) black synthetic iron oxide is 85/15 to 65/35,
The mass ratio ((2) / (3)) between the (2) black synthetic iron oxide and the (3) phosphoric acid anticorrosive pigment is 70/30 to 50/50,
A zinc-based black rust preventive agent characterized by containing carbon black . (4) a silane coupling agent and / or a titanium coupling agent;
(5) The zinc-based black rust preventive agent according to claim 1, further comprising an alcohol-based solvent. (1) a zinc pigment and / or a zinc alloy pigment, (2) black synthetic iron oxide, and (3) a phosphoric acid anticorrosive pigment.
The mass ratio ((1) / (2)) of the (1) zinc pigment and / or zinc alloy pigment to the (2) black synthetic iron oxide is 85/15 to 65/35,
The mass ratio ((2) / (3)) between the (2) black synthetic iron oxide and the (3) phosphoric acid anticorrosive pigment is 70/30 to 50/50,
A rust-preventing film containing no carbon black .   (4) The rust preventive film according to claim 3, comprising silicon oxide and / or titanium oxide.   The rust preventive film according to claim 3 or 4, wherein the zinc-based black rust preventive agent according to claim 1 or 2 is dried at 70 to 120 ° C and baked at 250 to 360 ° C.   A rust-proof metal member comprising the rust-proof coating according to any one of claims 3 to 5 on the surface of a metal substrate.   The rust-proof metal member according to claim 6, wherein the rust-proof film has a thickness of 5 to 20 μm.