JP4040912B2 - Colored rust preventive film forming treatment agent and forming method - Google Patents

Description

【００２３】
【表２】

【００２４】
【表３】

【００２５】
【表４】

【００２６】
【表５】

【００２７】
【発明の効果】
表１〜５から分かるように、本発明の保護被膜は様々な着色を有し、又、耐食性も高い。これに対して比較例の保護被膜は着色性が低くしかも短時間に悪化し、耐食性も低い。
本発明による酸性水溶液を用いることにより、有害な六価クロムを使用せず、従来の反応型クロメートと同様の処理方法で亜鉛表面に種々の色調の不溶性の強固な被膜を生成することが可能である。
本発明は記載された４つに分けられたグループから選択された三価クロム含有組成物により、単に六価クロムの公害問題を解決するだけでなく、更に従来の代替え技術では得難かった種々の色調を得ることが出来、意匠性を向上することが出来る。本発明の４つのグループ同士の組み合わせにより均一な黄色、濃い干渉色、黒色や褐色等、種々の外観が得られ意匠性を向上したうえ、更に、染料、顔料、樹脂やワックス等を含む組成物により、更なる意匠性の向上や摩擦係数を制御することを可能にした。[0001]
BACKGROUND OF THE INVENTION
The present invention is intended to protect various metals, but particularly relates to zinc or zinc alloys and metal materials plated with these metals, and particularly coloring iron parts plated with zinc and zinc-based alloys. It is about.
[0002]
[Prior art]
In general, zinc or zinc-based alloy plating (hereinafter referred to as zinc plating) is most widely used as a rust prevention method for ferrous materials and parts. However, when a galvanized iron-based material / part is used as it is, white rust, which is rust of zinc, is immediately generated, and therefore a protective film is generally further formed. A chromate film treatment is generally used as a protective film usually applied to galvanizing, and the chromate film treatment is further classified into three types: electrolytic chromate treatment, coating chromate treatment, and reactive chromate treatment. Moreover, it can be classified into white to blue gloss chromate, colored chromate mainly composed of yellow, green chromate, olive drap, and black chromate from the color tone of the appearance. The chromate treatment is applied not only to zinc but also to aluminum, cadmium, magnesium and the like.
[0003]
Chromate coatings are widely used because they are inexpensive and can easily obtain practical corrosion resistance, but all chromate treatment uses hexavalent chromium, which is harmful. However, it has become a big problem in recent years because it has a bad influence on the human body and the environment. This is a problem that cannot be solved as long as the chromate film is a film exhibiting corrosion resistance due to hexavalent chromium in the film.
[0004]
Various inventions have been filed so far for solving the problem of pollution of hexavalent chromium. For example, Japanese Patent Laid-Open Nos. 52-9236, 50-1934, 61-587, 2000-234177 JP-A-61-119677. These inventions can be noted in that no hexavalent chromium is used, but the appearance color tone is silver white to blue, and various color tones cannot be obtained as in conventional chromate using hexavalent chromium.
[0005]
Specifically, Japanese Patent Application Laid-Open No. 52-92836 treats zinc or a zinc alloy with an aqueous solution of one or more selected from the group consisting of Ti and phosphoric acid, phytic acid, tannic acid or hydrogen peroxide. It is characterized by that. The appearance after treatment is almost colorless and the corrosion resistance is very low. Even if the coating is baked after being processed on a steel plate and subjected to complicated, high-temperature and long-time treatment, the corrosion resistance with salt spray is only about 240 hours. JP-A-50-1934 describes a colorless glossy chromate composition of zinc or a zinc alloy comprising a mineral acid, a compound that generates trivalent chromium ions, a carboxylic acid, and optionally a reducing agent. As described, the coatings obtained with this composition have a glossy chromate appearance. The corrosion resistance in salt spray is a very low performance of 48 hours or less until the occurrence of white rust, and the composition is poor in liquid stability. JP-A 61-587 describes a composition containing trivalent chromium ions and silicates, fluorides and acids, but the coating obtained by this composition is also like a uniform gloss chromate. Appearance and corrosion resistance are as low as 24 hours or less until white rust occurs. Japanese Patent Application Laid-Open No. 2000-234177 describes a chemical conversion treatment solution for zinc or zinc alloy comprising a trivalent chromium compound and a titanium compound, a cobalt compound, a tungsten compound and a silicon compound. This treatment solution is expected to provide a conversion coating with relatively high corrosion resistance, but there are large variations for practical use in industry, the treatment conditions are relatively high for a long time, and the drying temperature is higher than before. In addition to the long time, the described treatment liquid has a problem of poor stability and precipitation in a few days. The resulting coating has a glossy chromate appearance like the others. JP-A-61-119677 describes an acidic composition containing trivalent chromium, iron, cobalt, nickel, molybdenum, manganese, aluminum, lanthanum, cerium, lanthanide, a mixture thereof, and nitric acid. Furthermore, compositions containing organic carboxylic acids and silicates are described. With this composition, it is possible to obtain a uniform gloss chromate appearance on zinc or a zinc alloy, but the corrosion resistance in salt spray was not sufficient, and white rust was generated for about 72 hours. In particular, a composition using an organic acid has poor liquid stability, and has a problem that the appearance of the treatment and the pH of the liquid change in several days to several weeks. JP-T-2000-509434 describes a greenish multicolored glossy film containing trivalent chromium. However, it is difficult to make a clear distinction from other appearances, assuming that the obtained coating is practically clearly green. Specifically, a conventional green chromate is a coating in which the metallic luster of the underlying galvanization is not visible at all (exactly unknown, but the coating itself appears to have a certain green color, The coating of the application is transparent and colorless and has a greenish multicolored gloss compared to a cloudy coating. If the image is obtained, the film obtained is like a soap bubble film adhering to the surface of zinc, and the color tone is close to glossy chromate, which is clearly different from the conventional green chromate.
[0006]
[Problems to be solved by the invention]
As described above, the prior art has problems of a single appearance (weak interference color such as gloss chromate, achromatic appearance), lack of stability, and lack of corrosion resistance. In particular, the problem of a single appearance is a major industrial problem, such as a design problem and the inability to properly use similar shaped parts.
[0007]
The object of the present invention is to stably produce a film having uniform and good appearance and corrosion resistance without using harmful hexavalent chromium in forming a protective film on the surface of metal, particularly zinc or zinc alloy. It is in. In particular, an alternative technique that has been invented so far is to easily provide a coating that solves the problems of design and appearance, for which an effective method has not been shown.
[0008]
[Means for Solving the Problems]
As a result of intensive studies by the present inventors in order to solve the problems in the prior art, various combinations that have not been obtained so far can be obtained by appropriately mixing various metals and specific groups arranged in appropriate combinations. It has been found that a film having a color tone of can be obtained. Further, after adding Si, Al, organic acid, or forming a colored coating, a protective coating is formed with a liquid composition containing at least one selected from the group consisting of silicon, resin, wax, ink, pigment, dye, and carbon. As a result, it has been found that the corrosion resistance can be improved, the friction coefficient can be controlled, and a deeper color tone can be obtained.
[0009]
That is, the present invention comprises (A) trivalent chromium ions, (B) Mo, W, Ti, Zr, Mn, Tc, Fe, Ru, Co, alkaline earth metal, Ni, Pd, Pt, Sc, Y, At least one or more of the group consisting of V, Nb, Ta, Cu, Ag, Au, (C) one or more of the group consisting of chlorine, fluorine, sulfate ion, nitrate ion, and (D) oxygen of phosphorus Provided is a method for forming a colored rust preventive film for a metal, comprising forming a rust preventive film from a liquid composition containing at least one member selected from the group consisting of an acid, an oxyacid salt, an anhydride, and a phosphorus compound.
Preferably, the liquid composition may further include at least one or more members selected from the group consisting of Si, Al, and organic acids.
Preferably, the liquid composition may further contain at least one or more selected from the group consisting of a stabilizer, a pigment, a dye, an ink, and carbon.
In the present invention, after forming a rust preventive film by the above film forming method, it is further treated with a liquid composition containing at least one of the group consisting of Si, resin, wax, ink, pigment, dye, and carbon. can do.
Metals to be treated by the method of the present invention include zinc, aluminum, magnesium, copper, nickel, chromium, iron, tin, and alloys between these metals or other metals.
[0010]
The present invention also provides (A) trivalent chromium ions, (B) Mo, W, Ti, Zr, Mn, Tc, Fe, Ru, Co, alkaline earth metals, Ni, Pd, Pt, Sc, Y, At least one or more members selected from the group consisting of V, Nb, Ta, Cu, Ag, and Au, (C) one or more members selected from the group consisting of chlorine, fluorine, sulfate ions, and nitrate ions, and (D) oxygen acid of phosphorus There is provided a metallized chemical conversion film forming treatment agent containing at least one member selected from the group consisting of oxyacid salts, anhydrides, and phosphorus compounds.
Preferably, the treatment agent may further include at least one or two of a group consisting of Si, Al, and an organic acid.
In another preferred embodiment, the treatment agent may further contain at least one or more members selected from the group consisting of a stabilizer, a pigment, a dye, an ink, and carbon.
In another preferred embodiment, any one of the above-described film-forming treatment agents may be used from Si, a resin, a wax, an ink, a pigment, a dye, and carbon for further treatment after the chemical conversion film formation by the film-forming treatment agent is performed. It is possible to combine with the 2nd film formation processing agent containing at least 1 sort (s) or more from the group which consists of.
The present invention can solve the problems of the prior art by using these methods or treatment agents.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Specifically, the present invention relates to trivalent chromium ions of 0.001 to 150 g / l, preferably 0.1 to 50 g / l, and 0.001 to 200 g / l, preferably 0.01 to 50 g / l. Mo, W, Ti, Zr, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, alkaline earth metal, Ni, Pd, Pt, Sc, Y, V, Nb, Ta, Cu, One or more of Ag and Au, 0.001 to 200 g / l, preferably 0.1 to 100 g / l of one or more of chlorine, fluorine, sulfate ion and nitrate ion, and 0.0001 to 300 g / l, preferably A method of forming a rust-preventing coating with a liquid composition containing 0.001 to 150 g / l of phosphorus oxyacid, oxyacid salt, anhydride, and phosphorus compound.
Preferably, 0.001 to 300 g / l, preferably 0.01 to 100 g / l, of one or more of Si, Al, organic acid, pigment, dye, ink and carbon can be contained.
Alternatively, a protective film may be further formed from a separate liquid composition containing one or more of Si, resin, wax, pigment, dye, ink, and carbon.
If any component is less than these ranges, the effect becomes poor. On the other hand, if it is excessive, the effect reaches a peak, and not only is the economic loss large, but in some cases, excessive film formation is not preferable because it causes deterioration in appearance (for example, uniformity and gloss) and corrosion resistance. .
[0012]
Further, if a combination is selected, a group consisting of trivalent chromium, Mo, W, Ti, Zr, Mn, Fe, Co, alkaline earth metal, Ni, Pd, Pt, V, Cu, Ag, and Au The combination of the group consisting of chlorine, sulfate ions and nitrate ions and at least one of the group consisting of phosphorus oxyacids, oxyacid salts and anhydrides provides a relatively uniform and good appearance. In addition, adding a plurality of metals to the combination of trivalent chromium, a group consisting of chlorine, sulfate ion, and nitrate ion and a group consisting of phosphorus oxyacid and oxyacid salt improves various performances. In particular, (A) a group consisting of trivalent chromium, (B) Mo, W, Ti, Zr, Mn, Fe, Co, alkaline earth, and (C) a group consisting of Ni, Pd, Pt, V, Ag, Au. And (D) a combination of one or more of the group consisting of chlorine, sulfate ion, and nitrate ion and (E) the group consisting of oxyacid and oxyacid salt of phosphorus has a better corrosion resistance and a coating with excellent appearance. Can be obtained. Further, when a combination of Si, Al, and an organic acid is further combined with these combinations, the corrosion resistance tends to be further improved.
[0013]
There is no particular designation for the method of supplying any metal, and other necessary components such as chlorides, sulfates, nitrates, and other inorganic components such as organic acid salts, oxoacids, oxoacid salts, etc. It is convenient because it can supply acid ions and the like, and in particular, sulfate compounds and nitrate compounds have good corrosion resistance. In addition to these, Si and Al can be supplied as oxides or colloidal oxides. In addition, the addition of a stabilizer to the liquid composition is effective for stabilizing the corrosion resistance and the design. Stabilizers include 0.1-100 g / l, preferably 0.5-50 g / l surfactant, hydrogen peroxide, heterocyclic compounds, ureas, aliphatic amines, acid amides, aminocarboxylic acids, ammonium Salts, aliphatic sulfonic acids and aromatic aldehydes are effective. Particularly preferred are nitrogen-containing compounds such as heterocyclic compounds, ureas, aliphatic amines, acid amides, aminocarboxylic acids, ammonium salts, and nitrogen-containing surfactants.
[0014]
The content of Si and Al in the composition used after the treatment with the above-described composition is 0.01 to 500 g / l, preferably 1 to 300 g / l. In some cases, a white appearance defect may occur. In any composition, the silicon compound is preferably sodium silicate, potassium silicate, lithium silicate, or colloidal silica having a particle size of 100 nm or less, more preferably 50 nm or less. As the aluminum compound, aluminum sulfate, aluminum chloride, alumina sol, aluminum stearate, aluminum silicate and the like are preferable.
[0015]
The resin is not particularly specified, but among them, Teflon resin, epoxy resin, acrylic resin, melamine resin, acrylic silica resin, and acrylic Teflon resin are preferable. It is necessary to select an appropriate concentration depending on the corrosion resistance and appearance (gloss, puddle, unevenness) and the like, and a high corrosion resistance of 1 to 800 g / l, preferably 10 to 500 g / l is easily obtained. Examples of the organic acid include carboxylic acids such as oxalic acid, malic acid, malonic acid, oxalic acid, acrylic acid, formic acid, acetic acid, tartaric acid, citric acid, glutamic acid, ascorbic acid, inosinic acid, and lactic acid. The content is suitably 0.1 to 500 g / l, preferably 1 to 200 g / l. When the amount is insufficient, the effect cannot be obtained. When the amount is excessive, the effect reaches a peak, resulting in an increase in economic loss and a poor appearance.
[0016]
There are various types of wax, but petroleum wax, polyurethane wax, polyethylene wax, polypropylene wax, and polyacrylic ester are preferable. Although it cannot be specified unconditionally depending on the required characteristics (friction coefficient, etc.), it can generally be used within a range of 0.01 to 400 g / l with little influence on other characteristics.
[0017]
Further, as preferable treatment conditions for the production of the rust-preventive coating with the liquid composition, the treatment time is 5 to 90 seconds, the treatment temperature is 10 to 80 ° C., the pH is 1.1 to 5.5, and more preferably the treatment time is 10 to 60 seconds. The temperature is 25 to 40 ° C. and the pH is 1.5 to 4. As preferable treatment conditions of the protective coating containing Si, resin, etc., treatment time 1 to 60 seconds, treatment temperature 5 to 80 ° C., pH 2 to 14, more preferably treatment time 10 to 40 seconds, treatment temperature 15 to 60 ° C., The pH is 3 to 6 or 8 to 13, and the processing temperature is 10 to 30 ° C. depending on the resin. As the treatment method, chemical conversion by immersion is the most excellent. When forming a film by electrolysis, it is possible to produce a film under conditions of 0.01 to 20 A / dm ² and 0.01 to 5 minutes, but electrolysis of 1 A / dm ² or more and electrolysis of 2 minutes or more are uneven in color. In some cases, it is recommended that the electrolysis is less than 1 A / dm ² or less than 2 minutes. As a method for forming a film, after treatment is performed under these conditions, rinsing is performed once, several times, or not performed at all. In the case of forming a protective film containing Si, resin, etc., after performing these treatments, a protective film containing Si, resin, etc. can be formed after drying or without drying.
[0018]
Protective coatings obtained by these combinations are able to obtain various uniform colors that could not be obtained in the past, improved not only in design but also in corrosion resistance equivalent to or better than colored chromate. be able to. Also, new functionality can be imparted, such as controlling the coefficient of friction by treating with a composition containing resin or wax.
[0019]
This method can perform treatment at a high temperature of 40 to 80 ° C. and a relatively long time of 45 to 90 seconds. However, depending on the application, the economical merit that a conventional reactive chromate treatment facility can be used as it is also of this method. It is also a feature. The treatment conditions for forming the coating can be the same as the conventional chromate treatment (liquid temperature 20 to 35 ° C., treatment time 20 to 40 seconds, with stirring), and a protective coating with a composition containing silicon, resin and wax. The treatment conditions for the production may be simply immersed at a liquid temperature of 20 to 50 ° C. for 20 to 40 seconds, and a series of treatments are very easy.
[0020]
[Action]
By using the acidic aqueous solution defined in the present invention, no harmful hexavalent chromium is used, and insoluble strong coatings of various colors are applied to the zinc surface with the same processing equipment, processing conditions and processing methods as conventional reactive chromate. Can be generated. As a result, not only general users who are worried about elution of hexavalent chromium from the treated product, but also health effects and effects on wild animals of chromate manufacturers and chromate treatment companies that have been exposed to the harmful effects of chromic acid. It becomes possible to solve the problem.
The present invention not only solves the pollution problem of hexavalent chromium by the trivalent chromium-containing composition selected from the four groups described, but also various problems that are difficult to obtain by conventional alternative techniques. A color tone can be obtained and design properties can be improved. That is, rust preventive coatings which do not use hexavalent chromium such as JP-A-52-92936, JP-A-50-1934, JP-A-61-587, JP-A-2000-234177, JP-A-61-119677 have been proposed. I came. However, many of these coatings have an appearance close to a silvery achromatic color exhibiting a light interference color like a conventional gloss chromate, and have poor design. Further, since the self-healing ability referred to in the conventional chromate coating is not present or very weak, when the coating is damaged, the corrosion resistance in the salt spray test is about 24 to 72 hours, which is not practical. In addition, a lot of things with moderate weight, such as bolts, are dropped or collided with each other (co-displacing during processing). The line did not perform well. In some cases, the composition lacks the stability of the treatment liquid. The reason why these problems can be solved by the present invention is considered to be because these conventional techniques do not satisfy all the four groups shown in the present invention and lack a part thereof. By combining the four groups arranged according to the present invention, various appearances such as uniform yellow, dark interference color, black and brown are obtained and the design is improved, and further, dyes, pigments, resins and waxes are included. The composition made it possible to further improve the designability and control the friction coefficient.
[0021]
【Example】
Hereinafter, the present invention will be described by way of examples. In the test, the test piece is subjected to appropriate pretreatment such as degreasing, pickling, desmutting, activation, etc., and then zinc plating (Zn), zinc-iron alloy plating (Zn / Fe), zinc-nickel alloy plating (Zn) / Ni) and then used. The plating film thickness was 8 to 9 μm in any plating. In Tables 1 to 5, all of the treatment liquid is an aqueous solution, and the component concentration of the treatment liquid is the amount of the component contained per liter of water. Evaluation was carried out by a salt spray test according to JIS Z 2371. The time when white rust occurs 5% is shown. Unless otherwise specified, no changes were observed in the liquid appearance, pH, and treated appearance after standing for 1 week.
[0022]
[Table 1]

[0023]
[Table 2]

[0024]
[Table 3]

[0025]
[Table 4]

[0026]
[Table 5]

[0027]
【The invention's effect】
As can be seen from Tables 1 to 5, the protective coating of the present invention has various colors and also has high corrosion resistance. On the other hand, the protective film of the comparative example has low colorability, deteriorates in a short time, and has low corrosion resistance.
By using the acidic aqueous solution according to the present invention, it is possible to produce insoluble strong coatings of various colors on the zinc surface by the same treatment method as conventional reactive chromate without using harmful hexavalent chromium. is there.
The present invention not only solves the problem of hexavalent chromium pollution by the trivalent chromium-containing composition selected from the four groups described, but also various problems that are difficult to obtain by conventional alternative techniques. A color tone can be obtained and design properties can be improved. A composition containing various dyes such as uniform yellow, dark interference color, black, brown, etc. by combining the four groups of the present invention to improve the design, and further containing a dye, pigment, resin, wax, etc. This makes it possible to further improve the design and control the friction coefficient.

Claims (10)

(A) trivalent chromium ion, (B) Ag, (C) one or more members selected from the group consisting of chlorine, fluorine, sulfate ion, nitrate ion, (D) phosphorus oxyacid, phosphorus oxyacid salt, anhydrides of phosphorus, colored antirust coating forming treatment agent of metal containing one or more of the group consisting of phosphorus compounds.   The metal coloring rust preventive film formation processing agent according to claim 1 whose concentration of Ag per liter of said composition is 0.2 g or more as silver nitrate.   The metal coloring rust preventive film formation processing agent according to claim 2 whose concentration of Ag per liter of said composition is 0.2-0.3g as silver nitrate.   The metal coloring according to any one of claims 1 to 3, further comprising at least one selected from the group consisting of Mo, Co, alkaline earth metals, Ni, Cu, Si, Al, and organic acids. Antirust coating forming treatment agent.   Further, a stabilizer or pigment selected from the group consisting of surfactants, hydrogen peroxide, heterocyclic compounds, ureas, aliphatic amines, acid amides, aminocarboxylic acids, ammonium salts, aliphatic sulfonic acids and aromatic aldehydes. 5. The metal colored rust preventive film forming treatment agent according to claim 1, comprising at least one selected from the group consisting of dye, ink, and carbon. Metal is zinc, aluminum, magnesium, copper, nickel, chromium, iron, tin, and film-forming treatment agent of metal according to any one of claims 1 to 5 which is selected from alloys thereof.   The film-forming treatment agent according to any one of claims 1 to 6 and Si, resin, wax, ink, pigment, dye, and carbon for further treatment after the formation of a rust-preventive film by the film-forming treatment agent. A metal combined film forming treatment agent with a second film forming treatment agent containing at least one or more of the group.   A method for forming a colored anticorrosive film of metal, comprising forming an antirust film with the film forming treatment agent according to any one of claims 1 to 5.   9. The metal according to claim 8, wherein the metal is further treated with a liquid composition containing at least one selected from the group consisting of Si, resin, wax, ink, pigment, dye, and carbon after forming the film. Colored rust preventive film forming method.   The method for forming a colored rust preventive film for a metal according to claim 8 or 9, wherein the metal is zinc, aluminum, magnesium, copper, nickel, chromium, iron, tin, or an alloy thereof.