TW200925335A - Zinc-electroplated steel sheet with excellent white rust resistance treated by chromate-free chemical conversion - Google Patents

Abstract

The invented zinc-electroplated steel sheet treated by chromate-free chemical conversion is to coat a chromate-free chemical conversion coating on a zinc-electroplated layer. Nickel contained within a range from an interface between the zinc-electroplated layer and the chromate-free chemical conversion coating to 0.04 μm deep in a depth direction of the zinc-electroplated layer is inhibited to 500 ppm in mass or less at atom level. With such configuration, the zinc-electroplated steel sheet treated by chromate-free chemical conversion has an excellent white rust resistance.

Description

200925335 IX. Description of the Invention [Technical Field of the Invention] The present invention relates to a galvanized steel sheet which is excellent in white rust resistance and non-chromate chemical conversion treatment. The galvanized steel sheet of the present invention is used, for example, in the fields of home electric appliances, automobile parts, building materials, and the like, and is particularly suitably used for applications such as chassis or case parts such as home appliances or OA machines, and steel furniture, which are mainly used indoors. ® [Prior Art] The ammonium zinc plate is used in the absence of coating depending on the application of the user. Therefore, white rust which is a rust of Zn which exhibits a sacrificial anticorrosive effect on the steel sheet is a problem. Therefore, a chromate-forming galvanized steel sheet which has been subjected to chromate formation treatment on a galvanized layer has been widely used for the purpose of improving white rust resistance. However, in recent years, from the viewpoint of the global environmental problem and the regulation of the use of hazardous substances, the galvanization of the non-chromium chemical conversion treatment which does not substantially contain the hexavalent chromium (Cr) non-chromate chemical conversion treatment is being actively carried out. In the development of steel sheets, research is being conducted to prevent white rust from occurring in galvanized steel sheets which are not treated with non-chromate. However, the bismuth zinc layer usually contains a trace amount of nickel (Ni). This is because, in actual production, Ni is inevitably mixed into the inevitable impurity element in the plating layer during the manufacturing process of the galvanized steel sheet. Specifically, for example, plating is performed by using a conductive roll of a Ni alloy such as a nickel-base alloy, or by mixing a Zn_Ni plating solution when switching from a galvanized steel sheet to a Zn-Ni alloy-plated steel sheet. The zinc layer contains Ni. It is disclosed in JP-A No. 2000-3 55790, JP-A-2004-263 252, and JP-A-200925335 No. 2006-265578, the amount of addition of Ni is controlled to improve the white rust resistance of the non-chromated chemically treated galvanized steel sheet. technology. Among them, JP-A No. 2000-355790 describes a method for controlling the amount of Ni in the entire galvanized layer to be in the range of 50 to 700 ppm mainly for suppressing blackening. The blackening phenomenon is observed in the early stage of the wet environment in which chloride ions are present before white rust occurs, and occurs in a relatively mild corrosive environment. The cause of black rust is the amorphous oxide of the so-called "ZnxO ! _x" which is produced by the Zn oxidation reaction (corrosion reaction). It is considered that the blackening is caused by the end of the oxidation reaction of Zn. of. Therefore, in this patent document, a predetermined amount of element Ni which is slightly more expensive than Zn is added for the purpose of appropriately promoting the oxidation reaction of Zn without causing the limit of white rust generation. In JP-A-2004-263252, attention is paid to a reaction layer formed at the interface between a non-chromate chemical conversion coating film and a galvanized layer, and if the alkali resistance of the reaction layer is increased, the alkali degreasing is also promoted. The manufacturer of corrosion resistance (white rust resistance) was implemented. Specifically, it is possible to achieve improved white embroidery resistance by controlling the total amount of Ni or the like contained in the plating surface portion within Ιμηη of the surface of the plating layer to be in the range of 50 to 3000 mg/m2. When the layer containing Ni or the like is too thick in the case of No. 2004-263252, the adhesion between the non-chromate chemical conversion coating film and the galvanized layer is lowered, and the pressure processing is performed. In the case where a part of the film is peeled off, the white rust resistance is not obtained, and a predetermined amount of non-metal Ni such as Ni is coexisted in a range of 50 nm or less from the plating surface. Improve white rust resistance. -6-200925335 [Disclosure of the Invention] [Problems to be Solved by the Invention] An object of the present invention is to provide a galvanized steel sheet which is excellent in white rust resistance and non-chromate chemical conversion treatment. [Means for Solving the Problem] The galvanized steel sheet of the non-chromate chemical conversion treatment of the present invention which solves the above-described problems has a non-chromate chemical conversion treatment film on the plating layer, and is formed of the galvanized layer and the non-chromate. Ni contained in the range from the interface of the film to the depth direction of the galvanized layer 〇·〇4μηη is suppressed to 500 ppm or less in terms of atomic weight (ppm means mass ppm, the same applies hereinafter). In a preferred embodiment, Ni in the galvanized layer is suppressed to 100 ppm or less in terms of an atom. Since the galvanized steel sheet of the present invention is constructed as described above, the white rust resistance of the non-chromated steel sheet is greatly improved. [Best Mode for Carrying Out the Invention] The present inventors have focused on Ni in an element which is inevitably contained in a galvanized layer in order to improve the white-proof property of a galvanized steel sheet which is not subjected to a chromate formation treatment. Conduct a review. As a result, (1) the amount of Ni in the entire shovel layer is controlled, and the generation of white rust cannot be sufficiently suppressed, as disclosed in Japanese Laid-Open Patent Publication No. 2009-25335--- It is necessary to control the amount of Ni present at the interface between the non-chromate formation treatment film and the galvanized layer; (2) The most surface portion of the shovel zinc layer which has a large influence on the improvement of white rust resistance (in detail, The area of the surface of the shovel layer is approximately 〇4〇ιη, as shown in JP-A-2004-263252, and only the amount of Ni of the surface portion of the plating layer (the range from the interface to the plating side of about 1 μm) is controlled. Insufficient, unevenness was observed in improving the white rust resistance. (3) As shown in the above (2), in order to appropriately control the amount of Ni in the outermost surface portion of the plating layer, it has been found that it is particularly necessary to set the temperature of the plating solution to be lower than the usual range (generally performed at 50 to 60 ° C), and complete The invention has been made. The foregoing will be described in detail. As described above, Ni is inevitably contained in the galvanized layer during the production of the non-chromate forming treated zinc-zinc steel sheet. Here, Ni in the galvanized layer is not uniformly distributed on the entire plating layer, and is often present on the surface side of the plating layer (on the interface side in contact with the non-chromate chemical conversion coating film), particularly in the present invention. In the "surface region" (a region in the range of about 0.04 μm from the interface side to the plating side), almost all of the "Ni concentrated layer" in which Ni is present in a metallic state was observed (refer to FIG. 4 described later). It is considered that Zn is selectively dissolved by the substitution reaction of Zn in the mineral zinc layer with Ni in the plating layer or the plating solution, and Ni is substituted for Zn to form metal Ni to precipitate (substitute precipitation). The "Ni-concentrated layer" produced by the substitution precipitation of Ni was observed in the "outermost surface region", and the "surface region" in the vicinity of the surfactant about Ιμιη specified in JP-A-2004-26 3 25 2 Not observed. Therefore, in order to secure excellent white rust resistance, it is important to control the amount of metal Ni in the "most surface region" observed in the Ni concentration layer -8 - 200925335, and based on this consideration, the present invention has been completed. In other words, according to the results of the review of the present invention, it is confirmed that the amount of metal Ni in the "surface region" specified in JP-A-2004-263252 does not necessarily have a high correlation with the white rust resistance, and it is observed that even if the "surface region" is controlled. The amount of Ni still has unevenness in characteristics such as a decrease in white rust resistance. On the other hand, compared with the patent document 2, a high correlation was observed between the amount of metal Ni present in the "outermost surface region" on the interface side and the white rust resistance, and it was found that it can be regarded as an extremely excellent evaluation index. On the other hand, in the case of JP-A-2006-265 579, attention is also paid to the "most surface area" (the area within 0.0 5 μm from the interface in the patent document) which is almost the same as the present invention, in an attempt to improve whitening resistance. Rust. However, in this patent document, in the "outermost surface region", a special plating treatment (using a plating solution containing a nitrate ion and a sulfate ion at a predetermined ratio) is used to precipitate Ni oxide which is almost absent. In an attempt to improve the white rust resistance, in this regard, without performing such a special plating treatment, it is possible to control the amount of the metal Ni in the "outermost surface region" in an attempt to improve the white rust resistance. different. Only the oxide of Ni was noted in this patent document, and the metal Ni was not completely noticed as in the present invention, and the experiment on the influence of the amount of metallic Ni present in the "outer surface region" on white rust resistance was not carried out at all. In the present specification, for convenience of description, the "galvanized layer" may be simply referred to as "plated Zn layer" or "plated layer". In addition, the galvanized steel sheet which has been subjected to non-chromate formation treatment is sometimes referred to as "non-chromate galvanized steel sheet" or -9 - 200925335 "chrome-free galvanized steel sheet", and non-chromate is converted into a treatment film. Simply quoted as "non-chromate film" or "chrome-free film". In addition, in order to distinguish the surface layer of the depth from the interface to the depth of 0.04 μm from the interface to the surface of the galvanized layer, it is possible to distinguish the surface layer from the interface to the depth of the galvanized layer by 0.04 μm. It is called the "most surface layer" or the "most surface area". Hereinafter, embodiments of the galvanized steel sheet according to the non-chromate chemical conversion treatment of the present invention will be described in detail with reference to Figs. 1 and 2 . As shown in the overall cross-sectional view of Fig. 1, the non-chromate chemically treated shovel-zinc steel sheet 10 of the present invention is sequentially subjected to a galvanized layer 2 and a non-chromate chemical conversion coating film 3 on the steel sheet 1. For example, as shown in a partial cross-sectional view of the interface 4 of the galvanized layer 2 and the non-chromate forming film 3, the area included in the range of the depth direction Ο.ίΜμιη from the interface 4 to the galvanized layer 2 ( The metal Ni contained in Fig. 2 and A) is controlled to be 500 ppm or less. Fig. 3 and Fig. 4 are diagrams showing the Ni amount distribution (depth direction distribution) of the galvanized layer of No. 1 (Inventive Example) and No. 24 (Comparative Example) of Table 1 of Examples to be described later. Fig. 3 shows the Ni amount distribution to the depth Ιμηη, and Fig. 4 shows the Ni amount distribution map in the depth of Fig. 3 to the depth Ιμχη. In Fig. 3 and Fig. 4, the amount of Ni (average 値) to the depth of Ιμιη (Fig. 3) and the amount of Ni (average 至 to the depth of 0·04μηη) of each No. 10 and No. 24 are recorded. 4) The number of 値. As can be seen from the above, the outermost regions of No. 10 (inventive example) and No. 24 (comparative example) each have a "Ni concentrated layer" and have a peak of Ni concentration in the vicinity of the interface about Ο.ΟΙμηη. Further, the results of the amount of Ni and the corrosion resistance of the outermost layer of No. 10 and No. 24 are as shown in the table, and the amount of Ni of the outermost layer from the interface of -10 200925335 to the depth of 0.04 μm is 1 5 . 98 ppm, No. 24 which is much higher than the upper limit (500 ppm) of the present invention, and a decrease in white rust resistance was observed. On the other hand, the amount of Ni in the outermost layer was 386 ppm, and No. 10 controlled within the range of the present invention. Excellent white rust resistance. Thus, the present invention is characterized in that the amount of metal Ni in the outermost layer existing within about 0.04 μm from the interface is suppressed to be less than 500 ppm. In the present invention, the Ni of the outermost layer exists almost entirely in the form of metal Ni, and may exist in the form of an oxide or the like. However, regardless of the form of Ni, it depends on the amount of metal Ni which controls the outermost layer. Further, in the above-mentioned Japanese Patent Publication No. 2006-265578, in order to precipitate the Ni oxide which is effective for improving the white rust resistance in the "outermost layer", acid plating of nitrate ions and sulfate ions in a predetermined ratio is required. The liquid is plated, but in the present invention, such special treatment is not required, and only the appropriate adjustment of the shovel temperature can control the amount of metal Ni which is extremely effective against white rust resistance, compared with JP-A-2006-265578. Positioned as an easier way to improve white rust resistance. In the present invention, the amount of Ni contained in the outermost layer of 0.04 μm from the interface is preferably as small as possible, whereby the white rust-improving effect can be improved. Since the amount of Ni in the outermost layer is particularly affected by the composition of the mash or the manufacturing line, etc., it is preferable to control the amount of Ni in an amount of about 200 ppm or less in order to obtain a desired effect. However, as shown in the above-mentioned JP-A-2000-3 5 5790, since the Ni-based element is effective for preventing the increase in resistance to blackening, the amount of Ni contained in the outermost layer is also attempted to improve the blackening resistance. It is preferably about 50 ppm or more. In the present invention, the measurement is included in the outermost layer of about 0·04 μm from the interface -11 - 200925335

The amount of Ni was carried out using a high frequency glow discharge optical emission spectroscopic apparatus (gD-OES • Glow Discharge Optical Emission Spectroscopy). The GD-OES analysis is a method of analyzing elements in the depth direction while scraping the sample from the surface (upper layer) of the sample by high-frequency sputtering. Specifically, 'the galvanized steel sheet before the non-chromatization treatment is cut into a sample of 50 mm x 50 mm size for analysis, and the Zn plating of the above sample is performed in the Ar glow discharge region, as described in detail in the Example column to be described later. The surface was subjected to high-frequency sputtering, and the amount of Ni in the depth direction from the interface to the galvanized layer was measured by continuously splitting the emitted light of the Ni element in the Ar plasma. The total amount of Ni in the depth of 〇4μηη divided by 0.04μηη 値 (average 値) is "the amount of metal Ni in the outermost layer". In the examples, a glow plasma discharge surface analysis device (GDA750, JY-5 000RF) manufactured by Rigaku was used, and analyzed under the following conditions.

Ar gas pressure: 2_5 hPa, electric power 30 W, frequency 50 Hz duty cycle 0.2 n In the present invention, Ni in the galvanized layer is preferably suppressed to 100 ppm or less in terms of atomic ratio. In the above-mentioned JP-A-2000-355790, the amount of Ni in the galvanized layer is lowered for the purpose of improving the white rust resistance, but in the present invention, the amount of Ni used to control the outermost layer is in the present invention. The method within the range is to adjust the amount of Ni in the galvanized layer. When the amount of Ni in the bismuth zinc layer is too large, the hardness of the plating layer is increased, and the adhesion of the shovel layer to the non-chromate chemical conversion treatment film is lowered, which is difficult to control the content of the amount of Ni in the outermost layer. Further, as shown in the column of the examples to be described later, it is judged that even if the amount of Ni in the galvanized layer is lowered and the amount of Ni in the outermost layer is large, it is not possible to ensure the required white rust resistance from -12 to 200925335. Based on the above, the amount of Ni suitable for controlling the shovel layer in the present invention. Further, the form of Ni in the galvanized layer is not particularly limited. For example, Ni in the outermost layer may be present as a metal or may be present as an oxide. In the present invention, the Ni to be plated may be controlled to be equal to or less than i 〇〇〇 ppm in atomic conversion, regardless of the manner in which Ni is present. The Ni in the yttrium zinc layer is as small as possible, whereby the amount of Ni in the outermost layer is substantially easily lowered. Specifically, it varies depending on the plating bath temperature, but is preferably about 500 ppm or less, and more preferably 200 ppm. The amount of Ni contained in the galvanized layer can be analyzed by inductively coupled plasma optical spectrometry (ICP) or inductively coupled plasma quality analysis (ICP-MS). In the analysis, in order to eliminate the measurement error caused by the matrix elements such as Zn, Na, and S contained in the ore solution, it is preferable to use the diluted plating layer. The dilution ratio is controlled in an appropriate range depending on the amount of the matrix element or the amount of Ni to be measured. In the examples described later, the amount of Ni in the plating layer was analyzed by diluting the plating layer by diluting twice the hydrochloric acid. Specifically, a non-chromium-treated galvanized steel sheet was cut into an analysis sample having a size of 50 mm x 50 mm, placed in a hydrochloric acid solution diluted twice as long, and immersed until the Zn-reaction reaction was completed to obtain an immersion liquid (1). In the present embodiment, the error caused by the substitution of the dissolved Ni on the surface of the steel sheet of the substrate is as soon as possible after the dissolution reaction of Zn is completed (in about 10 seconds, the above-mentioned layers are in the ore The following body hair method (within the concentration of hydrochloric acid in the middle, the test for dissolution of the acid salt test) -13- 200925335 Take out the above sample and immerse it in the newly prepared hydrochloric acid solution (2-fold dilution). In the second, the immersion liquid (2) is obtained. Then, the immersion liquids (1) and (2) obtained in this manner are brought to volume, and then an ICP-MS analyzer (PLASMAQUAD type manufactured by VGI Corporation) or an ICP analyzer (Shimadzu) is used. In the present embodiment, the ICP analyzer of the latter is used for analysis. In the galvanized layer 2, the plating adhesion amount is preferably about 3 g/m 2 or more. Even in the state after plating, good corrosion resistance (especially white rust resistance) can be obtained. From the viewpoint of corrosion resistance, the more the plating adhesion amount, the better, but if it exceeds l〇〇g/ At m2, the corrosion resistance improvement effect is saturated and economically wasted, so The upper limit is preferably about 1 g/m2, and the lower limit of the amount of plating adhesion is preferably 5 g/m2, more preferably 60 g/m2, and even more preferably 40 g/m2. 2 may be provided on at least a predetermined surface of the base steel sheet 1, and may be provided only on one surface of the steel sheet 1, or may be provided on both surfaces. The non-chromate chemical conversion coating coated on the galvanized layer 2 The term "substantially not contained" means the amount of Cr which is inevitably mixed in the production process of the non-chromate film. For example, in the present invention, non-chromate When a small amount of a Cr compound is eluted from a production container, a coating device, or the like in the process of preparing and coating the treatment liquid used for the film, Cr may be mixed in the film. Even in this case, the non-chromate film is formed. The amount of C r contained in the range is preferably about 〇. 〇1% by mass or less. As the non-chromate chemical conversion coating 3, a galvanized steel sheet treated with non-chromated to -14-200925335 can be used. The film generally used in the film can also be used (1) with organic resin as the main component. Any of the organic film and (2) the inorganic film mainly composed of an inorganic material. The configuration of the non-chromate chemical conversion film is not a characteristic part of the present invention. Hereinafter, such a film will be described in detail. (1) An organic chromium-free coating film mainly composed of an organic resin is used as the organic coating film, and typically includes an epoxy resin, a polyester resin, a polyurethane resin, an acrylic resin, and a polyethylene. An olefin-based resin such as polypropylene or an ethylene-acrylic acid copolymer, a styrene resin such as polystyrene, or an ethylene copolymer resin containing an ethylenically unsaturated carboxylic acid as a polymerization component, and a polyethylene-based system Resin, polyamine resin, fluorine-containing resin, and the like. Further, in addition to the above organic resin, an organic film containing a polyphenol compound such as tannic acid may be used. These organic coatings are suitable for satisfying particularly desirable characteristics in galvanized steel sheets for non-coating applications, such as corrosion resistance, fingerprint resistance, sag resistance, and electrical conductivity. The above-mentioned organic film is intended to improve the corrosion resistance, the lubricity, the scratch resistance, the workability, the weldability, the plating property, and the adhesion of the plating layer. Various types of oxide particles or inorganic pigments such as various phosphates, solid lubricants, crosslinking agents, and the like. Further, a wax particle 'organodecane compound, a naphthenate or the like may be contained. In the organic chromium-free coating film, a coating containing (a) a resin component containing a residue of -15-200925335 resin and (b) a Si-based inorganic compound (represented as colloidal cerium oxide) is used (hereinafter sometimes It is called "resin film"). By using the above-mentioned resin film, the effect produced by the steel sheet of the present invention (by controlling the amount of Ni in the outermost layer to improve the whiteness resistance effect) can be more effectively exhibited. In addition to significantly improving the white rust resistance, the alkali resistance is also enhanced. Degreasing property, coating property, etc. (refer to Example 2 mentioned later). The resin film is described in detail in Japanese Laid-Open Patent Publication No. Hei. No. 2006-43914, and the like. (a) Resin component of the carboxyl group-containing resin. The carboxyl group-containing resin is not particularly limited as long as it has a carboxyl group. For example, a monomer having a carboxyl group such as an unsaturated carboxylic acid may be used as a part or all of a raw material. A polymer synthesized by polymerization or a resin modified by a carboxylic acid by a reaction of a thiol group. A commercially available product may be used as the carboxyl group-containing resin, and examples thereof include Hitec S3141 (manufactured by State Chemical Co., Ltd.). The resin component may also include an organic resin other than the carboxyl group-containing resin. (b) Si-based inorganic compound The S i-based inorganic compound may, for example, be a citrate or a sulphur dioxide. These may be used singly or in combination of two or more. Among them, examples of the citrate include potassium citrate and lithium niobate. The cerium oxide may, for example, be a representative colloidal cerium oxide or scaly cerium oxide. In addition to this, dry cerium oxide such as pulverized cerium oxide, gas phase -16-200925335 cerium oxide, cerium sol or smoked lanthanum may be used. Among them, colloidal cerium oxide is particularly preferred. Thereby, in addition to the strength of the resin film, the ruthenium dioxide is concentrated in the ruthenium portion of the film in a corrosive environment to suppress rot of Zn, and the corrosion resistance is further improved. For the colloidal cerium oxide, a commercially available product may be used. For example, the SNOWTEX system 歹IJ "ST-40", "ST-XS", "ST-Nj, "ST-20L", "" manufactured by Nissan Chemical Industries Co., Ltd. ST-UP"' "ST-ZL", "ST- ❹ SS", "ST-O", "ST-AK", etc. The mass ratio of (a) the resin component constituting the resin film to (b) the Si-based inorganic compound (represented as colloidal cerium oxide) is about (a) resin component: (b) Si-based inorganic compound = 5 parts to 45 parts : 55 parts to 95 parts are suitable. When the content of the resin component is small, corrosion resistance, alkali degreasing property, and coating property tend to be lowered. On the other hand, when the content of the resin component is large, abrasion resistance, electrical conductivity, and the like are lowered. In addition, when the content of the Si-based inorganic compound is small, the wear resistance and the conductivity are lowered. When the content of the Si-based inorganic compound is large, the resin component is reduced, so that the film formation property of the resin film is small. Reduced, corrosion resistance is reduced. The resin film may further contain a decane crosslinking agent. By adding a decane crosslinking agent, since the bond between the carboxyl group-containing resin and the Si-based inorganic compound becomes strong, the white rust resistance is further increased. The decane crosslinking agent is preferably a compound having a lower alkoxy group such as an alkyl group, an allyl group or an aryl group having 1 to 5 carbon atoms. Specific examples thereof include r-glycidoxypropyltrimethoxydecane, r-glycidoxypropylmethyldimethoxydecane, r-glycidoxypropyltriethoxydecane, and r. -Epoxy-17- 200925335 propylene oxide-containing decane crosslinker such as propoxymethyldimethoxydecane; r-aminopropyltrimethoxydecane, aminopropyltriethoxydecane , N-(wan-aminoethyl)-r-aminopropyltrimethoxydecane, N-(/3-aminoethyl)-7-aminopropylmethyldimethoxydecane, etc. Alkane-containing decane cross-linking agent; vinyl-containing decane cross-linking agent such as vinyl trimethoxy decane, vinyl triethoxy decane, vinyl tris(methoxyethoxy) decane; a decane crosslinker containing methacryloxyloxy group, such as propylene oxypropyltrimethoxydecane, etc.; r-mercaptopropyltrimethoxydecane, r-mercaptopropylmethyldimethoxy A decane crosslinker containing a mercapto group such as decane; a halogen group-containing decane crosslinker such as r-chloropropyl methoxydecane or r-chloropropyltrimethoxydecane. These decane crosslinking agents may be used singly or in combination of two or more. Among the above, the decane crosslinking agent containing a glycidoxy group is particularly suitable because it is excellent in reactivity, corrosion resistance, and alkali resistance. For the decane cross-linking agent, a commercially available product may be used. For example, the content of a decane cross-linking agent such as r-glycidyloxypropyltrimethoxydecane "KBM403" (manufactured by Shin-Etsu Chemical Co., Ltd.) may be used. The total amount of the Si-based inorganic compound is preferably from 5 parts by mass to 25 parts by mass in terms of 100 parts by mass or less. When the content of the decane cross-linking agent is small, the reactivity of the carboxyl group-containing resin and the Si-based inorganic compound is lowered, and the abrasion resistance, the coating property, and the like are lowered, in addition to the ineffective effect of improving the white rust resistance. On the other hand, when the content of the decane cross-linking agent is too large, the stability of the film-forming liquid used for producing the resin film is lowered, and gelation is caused. In addition, since the amount of the cyan crosslinker which does not contribute to the reaction is increased in -18-200925335, the adhesion between the Zn plating layer and the chromate film is lowered. In the following, the constitution and preparation method of the modified film of the polyurethane film of the representative example of the resin film will be briefly described. However, the resin film of the present invention is not limited to this purpose. The resin film was obtained from the following aqueous resin solution. The resin contains 5 to 45 parts by mass of a carboxyl group-containing polyurethane resin water and an aqueous dispersion of an ethylene-unsaturated carboxylic acid copolymer as a nonvolatile component, and an average particle diameter of 5 to 95 parts by mass. ～20 nm of cerium-deposited particles' total of 10 parts by mass, relative to a total of 1 〇〇 by mass of a decane cross-linking agent having a ratio of 5 to 25 parts by mass, and a non-volatile resin of an aqueous solution of a polyethyl urethane resin The mixing ratio of the component (PU) to the non-volatile resin component of the aqueous dispersion of the ethyl acrylate copolymer, in mass ratio of PU: EC = 9: 1 to 2: 1. First of all, 'carboxyl-containing polyurethane resin The aqueous solution of the carboxyl group-containing polyurethane resin may be a water dispersion liquid in which a carboxyl group-containing polyurethane resin is dispersed in an aqueous medium or the above-mentioned carboxyl group-containing polyurethane The ester resin is dissolved in any of aqueous solutions in water. The aqueous medium may contain a trace amount of a solvent such as an alcohol, N-methylpyrrolidone or acetone in addition to water. The carboxyl group-containing polyurethane tree The fat is preferably obtained by subjecting the aminomethyl ester prepolymer to a chain extension reaction by a chain extender, and the urethane forging prepolymer can, for example, use a polyisocyanate component and a non-acid B liquid solution to be described later. The resin dioxane, the amino alkene-EC is used to react with the aqueous acid amine and the multi--19-200925335 alcohol component. As the polyisocyanate component constituting the aforementioned urethane prepolymer, at least one selected from the group consisting of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and dicyclohexylmethane diisocyanate (hydrogenated MDI) is used. The group of polyisocyanates is preferred. Here, as the polyol component constituting the ethyl urethane prepolymer, all of the polyhydric alcohols of the three types of 1,4-cyclohexanedimethanol, a polyether polyol, and a polyol having a carboxyl group are used. It is preferred to use all three kinds of diols. Further, the polyether polyol is not particularly limited as long as it has at least two hydroxyl groups in the molecular chain and the main skeleton is composed of epoxide units, and is not particularly limited, and examples thereof include polyoxyethylene diol and polyoxypropylene. Glycol, polyoxybutylene glycol, and the like. In addition, the chain extender which reacts the urethane prepolymer with a chain extension reaction is not particularly limited, and examples thereof include a polyamine, a low molecular weight polyol, and an alkanolamine. The aqueous liquid system for producing a carboxyl group-containing polyurethane resin can be emulsified in an aqueous medium by a known method, for example, by neutralizing a carboxyl group of a carboxyl group-containing polyurethane prepolymer with a base. A method of performing a chain extension reaction by dispersing; a method of emulsifying and dispersing a carboxyl group-containing polyurethane resin in a high shear force in the presence of an emulsifier to carry out a chain extension reaction. The following is a description of the aqueous dispersion of the ethylene-unsaturated carboxylic acid copolymer. The aqueous dispersion of the ethylene-unsaturated carboxylic acid copolymer is only required to disperse the liquid of the ethylene-unsaturated carboxylic acid copolymer in an aqueous medium. -20-200925335, the aforementioned ethylene-unsaturated carboxylic acid copolymer is a copolymer of a saturated carboxylic acid. The unsaturated carboxylic acid may, for example, be acrylic acid, crotonic acid, isocrotonic acid, maleic acid or fumaric acid, and may be polymerized with ethylene by a known high-temperature high-pressure polymerization method or the like to obtain a copolymer. The ethylene-unsaturated carboxylic acid copolymer has a carboxyl group (for example, an amine having a boiling point of 100 ° C or less) or a Na; ® ionic ion neutralizing the carboxyl group to obtain an aqueous dispersion. Here, the monovalent metal ion is used as described above, but the solvent resistance or the film hardness is effectively improved. As the monovalent substance, one or two or more kinds of hydroxides, carbonates or oxides containing such metals selected from the group consisting of sodium, potassium and lithium are preferred, and NaOH, KOH, LiOH or the like is preferably used, and NaOH is used. The present invention improves the contamination from this NaOH. The amount of the monovalent metal compound is preferably in the range of 0.02 to 0.4 mol with respect to the carboxyl group in the 1 mol of the acetonitrile carboxylic acid copolymer (the amount of the above metal compound is less than 〇.02). If it is less than 0.4 mol, the hygroscopicity (especially for the alkaline solution) increases, and the uranium deteriorates in the degreasing step. Therefore, it is not suitable. More suitable metal compounds 以下·〇3 Moer' The limit is 〇1 mol, and the metallization limit is 0.2 m. However, if the total amount of the organic base (the total amount of the amine valence metal compound having a boiling point of 1 or less) is excessive, It is preferably one of (meth) and itaconic acid, and is preferably a metal compound which is neutralized with an equivalent monovalent gold. - unsaturated 40 mole%) Mohr, the lower limit of the corrosion resistance of the resin film after the film is preferably the amount of the compound) and 1 because the water content of the -21,25,335, the viscosity of the dispersion rises rapidly and solidifies, Further, the excess alkali component causes deterioration of corrosion resistance, and is required to volatilize it. A lot of energy, it is not appropriate. However, if the amount of neutralization is too small, the emulsifying property is deteriorated, which is not preferable. Therefore, the total amount of the organic base and the monovalent metal compound to be used is preferably in the range of 0.3 to 1.0 mol with respect to the carboxyl group in the 1 mol of the ethylene monounsaturated carboxylic acid copolymer. The above aqueous dispersion of the ethylene-unsaturated carboxylic acid copolymer is dispersed in a very small particle (oil droplet) state having an average particle diameter of 5 to 5 Onm by emulsification with an organic base and a monovalent metal ion. Obtained in aqueous media. Therefore, it is estimated that the film-forming property of the obtained resin film, the adhesion to the metal plate, and the densification of the film are achieved, and the corrosion resistance is improved. The aqueous medium may contain a hydrophilic solvent such as an alcohol or an ether in addition to water. In addition, the particle diameter of the resin particles of the aqueous dispersion can be measured by, for example, a laser refractometry using a light-scattering luminometer (manufactured by Otsuka Electronics Co., Ltd.). As a method for preparing an aqueous dispersion of an ethylene-unsaturated carboxylic acid copolymer, an ethylene-unsaturated carboxylic acid copolymer and an aqueous medium are simultaneously added to, for example, a homogenizer device, etc., in response to the need of '70~2 5 0 Under the heating of °C, add an organic base such as an amine having a boiling point of 1 〇〇 ° C or less in a suitable aqueous solution or the like and a monovalent metal compound (first adding an amine having a boiling point of 100 ° C or less) or adding a boiling point substantially simultaneously. It is an amine having a concentration below 〇〇 °C and a monovalent metal compound), and is stirred with a high shearing force. Next, the aqueous solution of the carboxyl group-containing polyurethane resin obtained by the above method and the aqueous dispersion of the ethylene-unsaturated carboxylic acid copolymer and the cerium oxide particles and the decane crosslinking agent are blended in a predetermined amount. , -22- 200925335 With wax, cross-linking agent, etc. 'to obtain the desired aqueous resin solution. At any stage, cerium oxide particles, decane cross-linking agents, waxes, and crosslinking agents may be added, but the cross-linking reaction is not carried out after the crosslinking agent and the decane cross-linking agent are added, and gelation is not carried out. Heating is preferred. The above is an organic non-chromate film (resin film) to which the present invention is applied. (2) Inorganic non-chromium film mainly composed of an inorganic material The inorganic film used in the present invention is typically a phosphate such as zinc phosphate, iron phosphate, manganese phosphate, calcium phosphate or magnesium phosphate. The film is a film mainly composed of a phthalate such as sodium citrate, potassium citrate or lithium silicate. Alternatively, an inorganic film which is usually used, such as molybdic acid or vanadic acid, may be used. Among them, the inorganic film mainly composed of phthalate is particularly suitable for applications in which strong vibration is applied under pressure processing. The inorganic coating film may contain cerium oxide for the purpose of improving the properties such as corrosion resistance, lubricity, smear resistance, workability, weldability, plating property, and adhesion to a plating layer. Various inorganic particles such as oxide particles or various phosphates. Further, it may contain wax particles, an organic decane compound, a naphthalene acetate or the like. The non-chromate chemical conversion treatment film used in the present invention may be composed of only one layer type formed by the above (1) organic film or (2) inorganic film, or may be laminated. Composition. In the case of the latter laminated type, the order of combination is not particularly limited, and the lower layer may be an inorganic coating film, and the upper layer may be an organic coating film, or may be reversed. The number of layers is not limited to 2 layers -23- 200925335, and may be 3 layers or more. The non-chromate chemical conversion treatment film 3 used in the present invention may contain, in addition to the above-mentioned components, components which are usually contained (for example, an anti-skinning agent, a leveling agent, or the like, within a range not affecting the action of the present invention. Defoamer, penetrant, emulsifier, film forming aid, coloring pigment, lubricant, surfactant, conductive additive for conductivity, tackifier, dispersant, desiccant, stabilizer, mold inhibitor , preservatives, antifreeze, etc.). The thickness of the non-chromate chemical conversion treatment film 3 is preferably in the range of about 0.05 to 20 μm, and particularly preferably in the range of 0.2 to 2.0 μm. When the thickness of the resin film is less than 0.05 μm, the white rust resistance is lowered. On the other hand, when it exceeds 20 μm, the white rust improving effect is saturated, and the electrical conductivity or workability is lowered in addition to economical waste. In addition, in the above-mentioned FIG. 1, although the zinc-plated steel plate which coats the galvanized layer 2 and the non-chromate chemical conversion process film 3 on the steel plate 1 is shown, the steel plate of this invention is not limited to this, and it turns into non-chromate formation. In the treatment film 3, an organic resin film, an organic/inorganic composite film, an inorganic film, an electroplated coating film, or the like may be provided in order to improve corrosion resistance (especially white rust resistance) or coating property. Here, the above-mentioned organic resin film is substantially the same as the organic film constituting the non-chromate chemical conversion film 3 described above. Specifically, for example, a polyurethane resin, an epoxy resin, an acrylic resin, an olefin resin such as polyethylene, polypropylene, or an ethylene-acrylic copolymer, or a styrene resin such as polystyrene may be mentioned. In the case of a known resin for a coating such as a polyester or a copolymer or a modified product thereof, a film formed of a colloidal cerium oxide, a solid lubricant, a crosslinking agent or the like is required in accordance with the requirements of -24 to 200925335. In addition, the above-mentioned organic-inorganic composite film ’ can be generally exemplified by a combination of the above-described organic resin and a water glass forming component such as sodium citrate. In addition, the above-mentioned inorganic coating film 'is typically a water glass film or a film formed of lithium niobate. The following is a description of a method for producing a non-chromate galvanized steel sheet according to the present invention. First, a base steel plate (plated original plate) as a base is prepared. The bottom steel sheet is not particularly limited as long as it is a steel sheet used in a normal galvanized steel sheet. For example, various steel sheets such as ordinary steel sheets, A1 static steel sheets, and high tensile steel sheets can be used. The plated original plate is preferably subjected to pretreatment such as degreasing or pickling before galvanizing. Next, according to the mineral zinc method, a shovel layer is formed on the bottom steel plate to produce a galvanized steel sheet. The greatest feature of the present invention, in particular, is to control the plating temperature to be lower than usual (about 20 to 45 ° C) to appropriately adjust the amount of Ni in the outermost layer. As described above, by the precipitation reaction of Zn and Ni on the outermost layer, Ni is precipitated as a metal, and such a chemical reaction is sharp to the environment of the week, and the amount of precipitated metal is also significantly changed for the change of the plating temperature ( Refer to the examples described later). The relationship between the plating temperature and the manufacturing line or productivity of the steel sheet to be used is usually about 50 in actual production. (:, although it cannot be cooled to a lower temperature than it is, especially room temperature (about 30 °C), but -25-200925335 In the present invention, the amount of Ni for controlling the most surface area can be set more than the conventional one. When the plating temperature is about 50 ° C or higher, for example, the Ni concentration in the plating solution is appropriately controlled to appropriately control the amount of Ni in the entire plating layer, as it is still not suppressed. Since the amount of Ni in the outermost layer is lowered to a predetermined range, the desired white rust resistance cannot be obtained. Considering the white rust-improving effect or productivity, the plating temperature is preferably low, and is about 30 ° C or less. In the present invention, the conditions other than the above-described ore-covering temperature are not limited, and the other plating conditions other than the above are within a range that does not impair the action of the present invention, and can be appropriately set. In the present invention, a commonly used Zn plating solution such as a plating solution containing zinc sulfate and sulfuric acid, or a plating liquid containing zinc sulfate, a sodium sulfate, and an ammonium sulfate plating solution can be used. Not used in A shoveling liquid containing a compounding amount of nitric acid described in No. 2006-265 578. In the acidic plating bath, Ni is preferably controlled to be about 40 Oppm or less, whereby the outermost surface can be controlled relatively easily. The amount of Ni in the layer is within the range of the present invention, and the amount of Ni in the entire plating layer is easily controlled within a suitable range. The amount of Ni added in the plating solution is preferably as small as possible, preferably about 200 ppm or less, and more preferably 100 ppm or less. In this case, it is preferable to control the amount of Ni in the shovel liquid to be 400 ppm or less. The amount of Ni in the above range is preferably within the above range. As described above, Ni is usually an impurity which is inevitably mixed in the production process, and is sometimes actively added to the plating solution -26-200925335 to prevent blackening ( For example, refer to the above-mentioned JP-A-2006-2655 No. 78), which also means that the present invention contains the subject matter of any one mode, in other words, it is not limited to the subject matter of any one form. In addition, 'the amount of Ni and the galvanization for controlling the outermost layer are The amount of Ni in the layer In the range specified in the present invention, in addition to controlling the amount of Ni added in the acidic liquid as described above, it is preferable to use Zn as a raw material or an anode material used for galvanizing, etc. Specifically, control is used as a raw material Zn. When Ni is used in an amount of about 10 ppm or less, when a corrosion-resistant nickel-based alloy or the like is used as the anode material, the amount of Ni in the galvanized layer increases due to elution of the anode material, and substantially no Ni is used. The anode material (for example, a Ti electrode) is preferably used. When Ni is added to the plating solution, the method of adding Ni is not particularly limited, and any atomic conversion amount of Ni can be used in any form. For example, metal powder can be used. A metal form such as a metal foil may be added to the plating solution, or may be added in the form of a metal salt such as a sulfate, a chloride salt, a phosphate, a carbonate or an oxide salt. When it is added in the form of a metal salt, the valence of the element is not particularly limited, and a commonly used ruthenium can be used. In addition to the aforementioned elements, the plating solution may be added with other components which are usually added. For example, in order to improve conductivity and achieve a reduction in power consumption, a conductive auxiliary agent such as Na2S04, (NH4)2S〇4, KC1, or NaCl may be added. The pH of the plating solution is preferably in the range of about 0.5 to 4.0 in terms of current efficiency or plating phenomenon, and is preferably in the range of 1.0 to 2.0. The relative flow rate of the plating solution is preferably in the range of about 0.3 to 5 m/sec. In -27-200925335, the relative flow velocity refers to the difference between the flow direction velocity of the plating solution and the plate direction velocity of the steel plate of the original plate. The type of the electrode (anode) used for the electroplating is not particularly limited as long as it is a normal user, and examples thereof include a Pb-Sn electrode, a Pb-In electrode, a Pb-Ag electrode, and Pb-In-. In addition to the electrode for the Ag electrode or the like, there are a ruthenium oxide electrode, a zinc electrode, and the like. The plating tank can use any one of a vertical type and a horizontal type. The method of galvanizing ® is not particularly limited, and examples thereof include a constant current plating method and a pulse plating method. As described above, after the plating layer is formed, a non-chromate chemical conversion treatment film is formed based on a usual method. Before the non-chromate chemical conversion coating film is formed, for example, Co, Ni, Mo, V, phosphate, nitric acid can be used for the purpose of improving the film adhesion, improving the corrosion resistance, controlling the appearance, and the like on the surface of the plating layer. A known pretreatment of an amine such as a salt. In the following, a method of forming a resin film which is suitably used in the organic film according to the above (1) is described in detail. However, the present invention is not limited to the above. First, a resin component containing a predetermined amount of a carboxyl group and a Si-based inorganic substance are prepared. The compound is preferably a non-chromate chemical conversion treatment liquid (hereinafter sometimes referred to simply as "treatment liquid") containing a predetermined amount of a decane crosslinking agent. The treatment liquid is an aqueous solvent (e.g., hydrochloric acid or a nitric acid solution) which can completely dissolve the following components to dissolve or disperse. The mass ratio of the resin component contained in the treatment liquid to the Si-based inorganic compound is preferably in the range of the resin component: Si-based inorganic compound = 5 parts to 45 parts: -28 - 200925335 55 parts to 95 parts. When the amount of the resin component such as a carboxyl group-containing resin is small, corrosion resistance, alkali degreasing property, coating property, and the like tend to be lowered. On the other hand, when the content of the resin component is large, abrasion resistance and conductivity are high. Will wait. In addition, when the amount of the colloidal cerium oxide is small, the abrasion resistance and the electrical conductivity tend to be lowered. When the amount of the colloidal cerium oxide is large, the resin component is reduced, so that the film forming property of the resin coating is lowered. Corrosion resistance will be reduced. The treatment liquid may further contain a sand hospital crosslinker. The content of the sand-based crosslinking agent in the treatment liquid is preferably in the range of about 5 to 25 parts by mass based on the total of 100 parts by mass of the resin component and the Si-based inorganic compound, as shown in the examples below. When the content of the decane cross-linking agent is small, the reactivity of the carboxyl group-containing resin and the Si-based inorganic compound is lowered, and the abrasion resistance, the coating property, the corrosion resistance, and the like are lowered, in addition to the ineffective effect of improving the stain resistance. On the other hand, when the content of the decane crosslinking agent is too large, the stability of the coating liquid to be used in the production of the resin film is lowered, and gelation may occur. Further, since the amount of the decane cross-linking agent which does not contribute to the reaction increases, the adhesion between the Zn plating layer and the resin film is lowered. In addition to the above components, a wax or a crosslinking agent may be added to the treatment liquid as needed. Further, the treatment liquid may contain a component which is usually contained (for example, an anti-skinning agent, a leveling agent, an antifoaming agent, a penetrating agent, an emulsifier, a film forming aid, a coloring pigment) within a range not affecting the action of the present invention. , lubricants, surfactants, conductive additives for conductivity, tackifiers, dispersants, desiccants, stabilizers, mold inhibitors, preservatives, antifreezes, etc.) -29- 200925335 Contains The treatment liquid of the component is applied by a known method, for example, a light coating method, a spray coating method, a curtain coating method, a knife coating method, a bar coating method, a dip coating method, a brush coating method, or the like, and coating. When heating or drying is performed on one side or both sides of a metal plate, a plated steel plate having a desired resin film can be obtained. The heating and drying temperature is preferably carried out at a temperature at which the crosslinking reaction between the carboxyl group-containing resin to be used and the Si-based inorganic compound is sufficiently carried out (for example, a sheet temperature of about 90 to 100 ° C). Further, when a spherical polyethylene wax is used as the lubricant, the workability in the subsequent processing step is improved because the particle shape is maintained in advance, so that it is about 70 to 130. The non-chromate galvanized steel sheet obtained by drying in the range of (: is excellent in white rust resistance), so it is used in home electric appliances, automobile parts, building materials, etc., and is particularly suitable for use in mainly Use of a household appliance or an OA machine or the like, a chassis or a shell part, or a steel furniture, etc. [Embodiment] Embodiments Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not The present invention is not limited to the scope of the present invention, and is also included in the scope of the present invention. The following is also included in the technical scope of the present invention.重量质量质量。 -30- 200925335 Example 1 In this example, the effect of the amount of Ni contained in the range of the depth of the plating layer from the interface between the plating layer and the non-chromate coating on the white rust resistance in the range of 〇.〇4μηη was examined. In Example 1, an organic non-chromium film having a polyolefin-based resin as a base was produced and tested. (1) Preparation of a galvanized steel sheet As a plated original plate, A1 produced by a conventional method was used. The steel sheet was subjected to degreasing and pickling, and then subjected to electroplating using a plating solution having the following composition in a loop type plating apparatus having a plating area of 180 mm x 3 00 mm to obtain a galvanized steel sheet. The following components were added, and a mineral solution of N i in the form of a sulfate in the range shown in Table 1 was added.

ZnS04 · 7H2〇350g/L Na2S04 7〇g/L h2so4 20g/L Fe S〇4 · 7H2〇9g/L Fe2(S〇4)3.nH2〇(n = 9_5) 1.8g/L Na2MoO 4 · 2H20 0.03 g/L 40% Cr 2 (S04) 3 solution 0.9 g/L Sn standard solution 0.1 mg/L Other mineralization conditions are as follows. ❹ -31 200925335 • Current density: 5〇mA/dm2. Bath temperature: 20~60°C. Plating flow rate: 1 · 5ιη / sec • Electrode (anode) · IrOx electrode • Plating adhesion: 2〇g /m2 (2) A galvanized steel sheet having a non-chromate chemical conversion coating film is produced. On the other hand, in a polyolefin-based dispersion liquid ("CHEMIPEARL S100" manufactured by Mitsui Chemicals, Inc.), the solid content is 5% or more. The epoxy-based crosslinking agent ("Rikab〇nd AP3 5 5 B" manufactured by Chukoku Kogyo Co., Ltd.) and the solid content of 30% of the composition of the composition for forming a resin film for the surface layer of the facing resin (the same as the following) The above-mentioned cerium oxide particles having a particle diameter of 10 to 20 nm ("snowtex 40" manufactured by Nissan Chemical Industries, Ltd.) and a spherical polyethylene wax ("EMEMIPEARL W700" manufactured by Mitsui Chemicals, Ltd.) having a solid content of 5% or more are stirred. A composition for forming a non-chromated layer into a V-treated film was prepared. The composition was applied onto a galvanized steel sheet by a bar, and dried by heating at a plate temperature of 90 ° C for 1 minute to obtain a non-chromated composition of a veneer resin film having an adhesion amount of 1 g/m 2 . Treated galvanized steel sheet. (3) Analysis of the amount of Ni in the galvanized layer and in the outermost layer. The non-chromated chemically-treated galvanized steel sheet thus obtained is cut into a 50 mm x 50 mm-sized analytical sample, and the galvanized layer is analyzed based on the aforementioned method. The amount of Ni in the middle and the most surface layer. According to the method of measuring -32-200925335 of the present embodiment, the detection limit of the amount of Ni in the plating layer is 0.02 ppm, and the minimum detectable concentration of the amount of Ni in the outermost layer is 10 ppm. Further, for reference, the amount of Ni (the amount of Ni in the surface layer) from the interface to the depth of Ιμπι specified in JP-A-2004-263252 is measured in the same manner as the amount of Ni in the outermost layer. In this way, it is possible to compare which of the "most surface layer" in the present invention and the "the amount of Ni in the surface layer" specified in JP-A-2004-263 252 as an index of white rust resistance. (4) Evaluation of white rust resistance Each of the shovel-zinc steel sheets obtained as described above was subjected to a salt spray test prescribed in JIS Z2371, and the area ratio of white rust after 96 hours passed was determined by the following criteria, and the white rust resistance was evaluated. In the present embodiment, when the evaluation criteria is "?" or "〇", it is judged to be acceptable (example of the present invention).

◎: less than 5 % 〇: 5% or more and less than 10% △ : 10% or more and less than 50% X : 5 0 % or more These results are collectively shown in Table 1. -33- 200925335

Table 1 No. Ni concentration in the plating solution (ppm by mass) Ni amount of the plating layer (mass ppm) Plating solution temperature CC) White rust resistant coating overall from the interface to 0_04μιη Depth from interface to Ι.Ομιη depth 1 50 25 20 15 20 ◎ 2 75 48 63 35 20 ◎ 3 100 78 113 60 20 ◎ 4 200 159 271 234 20 ◎ 5 400 366 376 322 20 ◎ 6 25 16 16 12 26 ◎ 7 50 47 14 13 27 ◎ 8 75 71 109 55 26 ◎ 9 100 99 171 121 25 ◎ 10 200 233 386 289 28 ◎ 11 400 496 489 424 26 〇 12 100 111 221 128 30 〇 13 200 256 421 287 30 〇 14 100 135 200 183 40 〇 15 200 287 475 301 40 〇 16 100 321 685 287 50 Δ 17 200 556 987 621 50 Δ 18 25 69 566 89 60 Δ 19 50 155 623 194 60 Δ 20 75 215 533 300 60 Δ 21 100 301 771 322 60 Δ 22 150 454 862 553 60 X 23 200 669 1218 790 60 X 24 300 875 1598 1019 60 X 25 400 1150 2049 1450 60 X From Table 1, the following can be considered.

No. 1 to 15 are examples in which the low temperature region recommended in the present invention is controlled at a plating bath temperature of 40 ° C or lower to perform plating, since the gold-34-200925335 which suppresses the outermost layer is in the range of the present invention. In addition, the amount of Ni in the entire plating layer is also controlled to an appropriate range, so that it is excellent in white rust resistance. In particular, when the temperature of the controlled ore solution of No. 1 to 10 is lower than about 28 t, the white rust resistance is further improved. On the other hand, N 〇. 6 6 to 2 5 is a plating solution having a high temperature of about 50 to 60 ° C for plating, since the amount of Ni of any of the outermost layers exceeds the range of the present invention. Therefore, the white rust resistance is lowered. In this case, the comparative review controls the temperature of the ore to the lower No. 1 to 15 and the concentration of N i in the plating solution is the same when the temperature of the ore solution is set to be higher than N 〇. 1 6 to 2 5 In general, the following trend can be observed as a whole. The lower the shovel temperature, the lower the amount of Ni in the entire ruthenium layer, and the amount of Ni in the outermost layer also decreases. In addition, when attempting to "the amount of Ni to the depth of Ι.Ομπι" (the amount of Ni in the surface layer) specified in JP-A-2004-263252, it is confirmed that the amount of Ni in the surface layer and the white rust resistance are not necessarily high. Relevant relationship. Even if the amount of Ni in the surface layer is increased to 322 ppm of No. 5 and lowered to 12 ppm such as Νο·6, these can exhibit good white rust resistance. On the other hand, in the comparative example, the amount of Ni in the surface layer of No. 18 was as low as 89 ppm, but the white rust resistance was poor, and it was found that the amount of Ni in the surface layer was not a good indicator for evaluating white rust resistance. . Further, it is understood from Table 1 that the present invention example of Nos. 1 to 15 is different from the steel sheet of JP-A-2004-263252. In other words, the amount of Ni from the surface to Ιμηη is 50 to 3000 mmg/m 2 as defined in the third paragraph of the above-mentioned Patent Application No. 2004-263252, and the specific gravity of Zn is 7.14 g/cm 3 ' - 35- 200925335 When the ppm conversion is performed, it is about 7100~46500PPm, and the Ni amount of the surface layer of JP-A-2006-265 5 78 is farther than any steel sheet of the present invention (maximum No. ll of 424 ppm). More. Further, it is judged that the amount of Ni in the entire shovel layer is not an effective index for evaluating white rust resistance. In other words, Nos. 16 to 24 in Nos. 16 to 25 of Table 1 are examples in which the amount of Ni in the shovel is appropriately controlled, and the amount of Ni in the entire plating layer is also controlled to be within a suitable range of the present invention of 1000 ppm or less. The amount of metal Ni in the outermost layer is outside the range of the present invention, and thus the desired white rust resistance cannot be obtained. Further, even if the concentration of Ni in the plating solution is controlled to the same level, the amount of Ni in the outermost layer or the amount of Ni in the entire plating layer largely changes depending on the temperature of the plating solution. In Table 1, No. 11 (Example of the present invention) and No. 25 (Comparative Example) are examples in which the amount of Ni in any of the plating solutions is 400 ppm, but in No. 1 1 because the control is as in the present invention. The predetermined low shovel temperature is such that not only the amount of Ni in the entire plating layer but also the amount of Ni in the outermost layer is lower than the range of the present invention, and the white rust resistance is also good. On the other hand, since the plating solution temperature in the No. 25 is set to 60 t, which is higher than the conventional one, the amount of Ni in the outermost layer and the entire plating layer is increased, and the white rust resistance is lowered. In this manner, even if the concentration of Ni in the plating solution is controlled to the same extent, the rate of the precipitation reaction of the Zn and Ni varies greatly depending on the temperature of the plating solution. Therefore, the amount of Ni in the outermost layer or the amount of Ni in the entire plating layer changes significantly. This confirms that the white rust resistance is also greatly affected. From the above results, it was confirmed that in order to ensure good white rust resistance, it is only necessary to control the amount of Ni in the entire plating layer or the amount of Ni in the surface layer within the interface ιμιη-36-200925335, and control the maximum within 0.04 μm from the interface. The amount of metal Ni in the surface layer is extremely important. Therefore, it is preferred to control the temperature of the plating solution to a temperature of about 40 ° C or less. (Example 2) In the same manner as in Example 1 ©, except for using a non-chromate chemical conversion non-chromate coating film having a non-chromate coating film different from Example 1, Ni was investigated for the outermost layer. The effect of the amount on white rust resistance. Specifically, in the present embodiment, an organic non-chromium film (resin film) was produced by the method described in Example 1 of JP-A-2006-43913, and the temperature of the plating solution was changed to carry out an experiment. (1) Preparation of resin aqueous liquid Here, a resin is prepared from a carboxyl group-containing polyurethane resin aqueous solution, an ethylene-unsaturated carboxylic acid copolymer aqueous dispersion, cerium oxide particles, and a wax-containing tree oil aqueous solution. Membrane. The specific production method is as follows. (1-1) Preparation of a carboxyl group-containing polyurethane resin aqueous solution In a synthesis apparatus having a stirrer, a thermometer, and a temperature controller having a content of 0.8 L, 60 g of a soil preservation chemical industry (as a polyol component) was added ( Co., Ltd. to prepare tetramethyl ether glycol (average molecular weight of 1000), 14g of 1,4-cyclohexanedimethanol, 20g of dimethylolpropionic acid, and then '3O.Og as a reaction solvent N-methylpyrrolidone. 1 to 4 g of toluene diisocyanate which is an isocyanate component (hereinafter referred to as "TDI" in the case of -37 to 200925335) was added, and the temperature was raised from 80 to 851:, and the reaction was allowed to proceed for 5 hours. The obtained prepolymer had an NCO content of 8.9%. Further, 6 g of triethylamine was added for neutralization, and 16 g of a mixed aqueous solution of ethylenediamine and 480 g of water was added, and emulsification was carried out at 5 (TC for 4 hours to carry out a chain extension reaction) to obtain a polyaminocarboxylic acid. An aqueous dispersion of ethyl ester resin (non-volatile resin component is 29.1 %, acid strontium is 4 1 _ 4 ). (1 -2 ) Preparation of an aqueous dispersion of an ethylene-unsaturated carboxylic acid copolymer with a stirrer and a thermometer In the autoclave of the emulsifier apparatus having a temperature controller of 〇.8 L, 626 parts by mass of water and 160 parts by mass of ethylene-acrylic acid copolymer (20% by mass of acrylic acid, melt index (MI) of 300) were added. Adding 40 mol% of triethylamine and 15 mol% of sodium hydroxide to the carboxyl group of 1 mol of the ethylene-acrylic acid copolymer, stirring at 150 ° C, 5 Pa, and cooling to An aqueous dispersion of an ethylene-acrylic acid copolymer was obtained at 40 ° C. Next, 4,4'-bis(extended ethyliminocarbonylamino)diphenylmethane as a crosslinking agent was added to the above aqueous dispersion. (Japanese Catalyst, ChemititeDZ-22E, Chemitite) is a registered trademark. The ratio of the nonvolatile resin component of the ethylene-acrylic acid copolymer to 100 parts by mass is 5 parts by mass. (1-3) The aqueous solution of the preparation resin is obtained from the carboxyl group-containing polyurethane obtained as described above. Aqueous resin liquid, the above-mentioned ethylene-acrylic acid copolymer aqueous dispersion, colloidal cerium oxide ("ST-XS" manufactured by Nissan Chemical Industries Co., Ltd., average particle diameter of 4 to 6 nm) -38 - 200925335 'is non-volatile When the total amount of the components is 100 parts by mass, the blending ratio of '5 parts by mass: 25 parts by mass: 70 parts by mass' is added to 10 parts by mass of the total of 10 parts by mass of the decane crosslinking agent. Glycidoxypropyltrimethoxydecane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM4 03), to prepare an aqueous resin solution. The resin film obtained in this manner contains a resin component, colloidal cerium oxide, and a decane crosslinking agent in terms of mass ratio. About resin component: Glue® ruthenium dioxide: decane crosslinker = 30 parts: 7 parts: 10 parts. (2) Preparation of galvanized steel sheet having a resin film The aqueous solution of the resin obtained in the above (1) is borrowed. Squeezed by rollers Method coating (single-side coating) on the shovel-zinc steel sheet obtained in (1) of Example 1 was heated and dried in a laboratory furnace at a furnace temperature of 220 ° C and a sheet temperature of 95 ° C to obtain a thickness of a non-chromated chemically treated galvanized steel sheet of a resin film (non-chromate film) of 〇·5 μιη. 〇 The white rust resistance of the non-chromate galvanized steel sheet thus obtained was measured in the same manner as in Example 1. The amount of Ni. - These results are shown in Table 2. -39- 200925335

Table 2 No. Ni concentration in the plating solution (ppm by mass) Ni amount of the plating layer (mass ppm) Plating solution temperature rc) White rust resistant plating as a whole from the interface to 0.04μηι Depth from the interface to Ι.Ομπι depth 26 50 25 20 15 20 ◎ 27 75 48 63 35 20 ◎ 28 100 78 113 60 20 ◎ 29 200 159 271 234 20 ◎ 30 400 366 376 322 20 ◎ 31 25 16 16 12 26 ◎ 32 50 47 14 13 27 ◎ 33 75 71 109 55 26 ◎ 34 100 99 171 121 25 ◎ 35 200 233 386 289 28 〇 36 400 496 489 424 26 〇 37 100 111 221 128 30 〇 38 200 256 421 287 30 〇 39 100 135 200 183 40 〇 40 200 287 475 301 40 〇 41 100 321 685 287 50 Δ 42 200 556 987 621 50 Δ 43 25 69 566 89 60 X 44 50 155 623 194 60 X 45 75 215 533 300 60 X 46 100 301 771 322 60 X 47 150 454 862 553 60 X 48 200 669 1218 790 60 X 49 300 875 1598 1019 60 X 50 400 1150 2049 1450 60 X Νο·26~40 is a temperature controlled by the present invention for controlling the temperature of the plating solution to be about 20 to 40 ° C for plating. For example, since the amount of metal Ni present in the outermost layer is controlled within the scope of the present invention And also controls the entire coating -40-200925335 Ni amount in a suitable range, an excellent white rust resistance.

On the other hand, No. 41 to 50 is an example in which the temperature of the plating solution is about 50 to 60 ° C and is plated at a higher temperature than the present invention, since the amount of Ni in any of the outermost layers exceeds the present invention. In the range of the white rust resistance, the white rust resistance is reduced. As described above, even when the composition of the non-chromium film is changed to the resin film instead of the inorganic film shown in the first embodiment, the same effect as in the first embodiment can be confirmed. (Example 3) In the same manner as in Example 1, except that the galvanized steel sheet having the non-chromate film forming process of the non-chromate film different from Example 1 was used, the amount of Ni in the outermost layer was examined. The effect on white rust resistance. Specifically, in the present embodiment, a phosphate film was produced by the method shown below, and the temperature of the plating solution was changed to carry out an experiment. As the phosphate treatment liquid, an impregnated zinc phosphate-based treatment liquid "PB-33 12" manufactured by Parkerizing Co., Ltd., Japan was used. The above treatment liquid had a free acidity (FA) of 2.4 points and a total acidity (TA) of 16.9 points. Here, the meanings of FA and TA are as follows. (a) FA: using bromophenol blue as an indicator, and using 0.1N sodium hydroxide solution as a titration solution for titration with respect to 10 mL of the phosphate treatment solution, until the color of the treatment liquid is changed from yellow to blue. The number of mL of the titrant was set to FA point. (b) TA: relative to 10mL of phosphate treatment solution, using phenolphthalein-41 - 200925335 as an indicator, using 0 · 1 N sodium hydroxide solution as a titration solution for titration, until the color of the treatment liquid is pink The number of mL of the required titrant is set to ΤΑ. In the following, the phosphate treatment liquid described above is subjected to phosphate treatment in the order of (1) to (6) below. (1) pickling: immersed in 2% sulfuric acid solution for 5 seconds (2) water washing: 30 seconds 〇 (3) surface conditioning: immersion at room temperature (4) chemical conversion treatment: immersion in the above phosphoric acid at 60 ° C 5 seconds in the treatment liquid (5) water washing: 15 seconds (6) drying: drying at 70 ° C until the surface was dried. The zinc-coated steel sheet having the phosphate film obtained in this manner was treated in the same manner as in Example 1 to carry out a salt spray. In the test, the area ratio of white rust after 24 hours passed was judged by the following criteria, and the white rust resistance was evaluated. In the example, in the case of the example, when the evaluation criterion is "◎" or "〇", it is judged to be acceptable (example of the present invention). ◎: less than 5 % 〇: 5% or more, less than 1 〇 % △ : 10% or more, less than 50% x : 5 0 % or more These results are shown in Table 3. -42- 200925335 Table 3

❹

No. Ni concentration in the plating solution (ppm by mass) Ni amount of the plating layer (mass ppm) Plating solution temperature rc) White rust-resistant plating overall from the interface to 0.04μπι Depth from the interface to Ι.Ομηι depth 51 50 25 20 15 20 〇 52 75 48 63 35 20 〇53 100 78 113 60 20 〇54 200 159 271 234 20 〇55 400 366 376 322 20 〇56 100 111 221 128 30 〇57 200 256 421 287 30 〇58 100 135 200 183 40 〇59 200 287 475 301 40 〇60 100 321 685 287 50 Δ 61 200 556 987 621 50 X 62 25 69 566 89 60 X 63 50 155 623 194 60 X 64 75 215 533 300 60 X 65 100 301 771 322 60 X 66 150 454 862 553 60 X 67 200 669 1218 790 60 X

No. 51 to 59 are examples in which the temperature of the plating solution is controlled to be about 20 to 4 (TC is the temperature specified in the present invention for plating, since the amount of metal Ni present in the outermost layer is controlled within the scope of the present invention. In addition, the amount of Ni in the entire plating layer is controlled to a suitable range, so that it is excellent in white rust resistance. In contrast, N 〇. 6 0 to 6 7 is such that the temperature of the plating solution is about 50 to 60 ° C. In the case of plating at a higher temperature than the present invention, since the amount of Ni in any of the outermost layers exceeds the range of the present invention, the white rust resistance is lowered. As described above, even if the composition of the non-chromium film is changed to resin In the case of the inorganic film shown in the first embodiment, the same effect as in the first embodiment can be confirmed. Fig. 1 is a schematic view showing the overall structure of the galvanized steel sheet of the present invention. Fig. 2 is a partial cross-sectional view showing the interface 4 of the galvanized layer 2 and the non-chromated layer formed into the film 3 in Fig. 1. Fig. 3 is No. 10 of Table 1 of the embodiment. The distribution of the amount of Ni in the galvanized layer of this example) and N〇_24 (comparative example) (to the depth ΐμι Fig. 4 is a diagram showing the distribution of the amount of Ni (to the depth Ο.ίμιη) of the galvanized layer of Ν 〇.10 (this embodiment) and Ν〇24 (comparative example) of Table 1 of the examples. Fig. [Description of main component symbols] 1 : Steel plate 2: Zinc plating layer 3: Non-chromate chemical conversion coating film 4: Interface 5: Non-chromate chemical conversion treatment of galvanized steel sheet - 44 -

Claims (1)

200925335 X. Patent Application Area 1. A non-chromate chemical conversion treatment of a shovel zinc steel sheet, which has a non-chromate chemical conversion treatment film on a galvanized layer, and a galvanized layer and a non-chromate chemical conversion treatment film. B [Suppression of the range of 0.04 μm in the depth direction of the galvanized layer is 5 〇〇 ppm or less in terms of atomic weight (ppm means the same or less). 2 'In the non-chromate chemical conversion treatment of the first application of the patent scope #, the & in the galvanized layer described above is suppressed to an atom of 0.01 ppm or less. ❹ Yes, interface to Ni, converted to galvanized by ppm, -45-