阅读说明：本技术 化学转化处理剂、具有化学转化皮膜的金属材料的制造方法以及具有化学转化皮膜的金属材料 (Chemical conversion treatment agent, method for producing metal material having chemical conversion coating, and metal material having chemical conversion coating ) 是由 岩崎弘资 对木雄悟 安玄洙 于 2020-03-02 设计创作，主要内容包括：本发明的目的在于提供能够在金属材料的表面或表面上形成耐腐蚀性优异的、着色的化学转化皮膜的化学转化处理剂等。本发明通过含有离子(A)、离子(B)、包含氟的离子(C)及酸性染料(D)的、上述离子(C)的摩尔浓度相对于上述离子(A)的摩尔浓度为6倍以上的化学转化处理剂实现了上述目的,上述离子(A)包含选自锆、钛及铪中的金属元素,上述离子(B)包含选自铬、铁、钴、钒及铜中的金属元素。(The purpose of the present invention is to provide a chemical conversion treatment agent or the like capable of forming a colored chemical conversion coating film having excellent corrosion resistance on the surface of a metal material or on the surface thereof. The object is achieved by a chemical conversion agent containing an ion (A), an ion (B), a fluorine-containing ion (C), and an acid dye (D), wherein the molar concentration of the ion (C) is 6 times or more the molar concentration of the ion (A), the ion (A) contains a metal element selected from the group consisting of zirconium, titanium, and hafnium, and the ion (B) contains a metal element selected from the group consisting of chromium, iron, cobalt, vanadium, and copper.)

1. A chemical conversion treatment agent comprising an ion (A), an ion (B), a fluorine-containing ion (C) and an acid dye (D),

the ion (A) contains a metal element selected from zirconium, titanium and hafnium, the ion (B) contains a metal element selected from chromium, iron, cobalt, vanadium and copper,

the molar concentration of the ion (C) is 6 times or more of the molar concentration of the ion (A).

2. A method for producing a metal material having a chemical conversion coating, comprising the step of bringing the chemical conversion treatment agent according to claim 1 into contact with the surface of the metal material or the surface thereof.

3. A metal material having a chemical conversion coating film, which is obtained by the production method according to claim 2.

Technical Field

The present invention relates to a chemical conversion treatment agent for producing a chemical conversion coating on a surface of a metal material, a method for producing a metal material having a chemical conversion coating using the chemical conversion treatment agent, and a metal material having a chemical conversion coating produced by the production method.

Background

Conventionally, development of a chemical conversion treatment agent capable of forming a chemical conversion coating film excellent in corrosion resistance has been carried out. For example, patent document 1 discloses a treatment liquid containing a liquid composition containing (a) trivalent chromium, (B) zirconium ions, (C) one or more selected from chloride ions, sulfate ions and nitrate ions, (D) aromatic sulfone and (E) fluoride ions.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-38255.

Disclosure of Invention

Problems to be solved by the invention

The purpose of the present invention is to provide a chemical conversion treatment agent or the like capable of forming a colored chemical conversion coating film having excellent corrosion resistance on the surface of a metal material or on the surface thereof.

Means for solving the problems

The present inventors have conducted extensive studies to solve the above problems, and as a result, have found that a chemical conversion treatment agent containing an ion (a) containing a metal element selected from zirconium, titanium and hafnium, an ion (B) containing fluorine (C) and an acid dye (D) and having a molar concentration of the ion (C) 6 times or more as high as that of the ion (a) and a metal element selected from chromium, iron, cobalt, vanadium and copper can form a colored chemical conversion coating film having excellent corrosion resistance, and have completed the present invention.

The present invention includes the following.

[1] A chemical conversion treatment agent comprising an ion (A) containing a metal element selected from the group consisting of zirconium, titanium and hafnium, an ion (B) containing a metal element selected from the group consisting of chromium, iron, cobalt, vanadium and copper, and an acid dye (D), wherein the molar concentration of the ion (C) is 6 times or more the molar concentration of the ion (A).

[2] A method for producing a metal material having a chemical conversion coating, comprising the step of bringing the chemical conversion treatment agent according to [1] into contact with the surface of the metal material or the surface thereof.

[3] A metal material having a chemical conversion coating film, which is obtained by the production method according to [2 ].

Effects of the invention

According to the present invention, a chemical conversion treatment agent capable of forming a colored chemical conversion coating film having excellent corrosion resistance on the surface of a metal material or on the surface thereof can be provided. The present invention can also provide a method for producing a metal material having a chemical conversion coating by forming a chemical conversion coating on a surface or a surface of a metal material using the chemical conversion treatment agent, and a metal material having a chemical conversion coating produced by the production method.

Detailed Description

A chemical conversion treatment agent according to an embodiment of the present invention includes an ion (A) containing a metal element selected from zirconium, titanium, and hafnium, an ion (B) containing a metal element selected from chromium, iron, cobalt, vanadium, and copper, and an acid dye (D), and the molar concentration of the ion (C) is 6 times or more the molar concentration of the ion (A). By using such a chemical conversion treatment agent, a colored chemical conversion coating film having excellent corrosion resistance can be produced on the surface of a metal material or on the surface of the metal material. The chemical conversion treatment agent of the present embodiment may be a chemical conversion treatment agent in which only the supply source of the ion (a), the supply source of the ion (B), the supply source of the ion (C), and the acid dye (D) are blended in an aqueous medium, or may be a chemical conversion treatment agent in which other components are further blended. The chemical conversion treatment agent of the present embodiment may or may not contain a phosphorus-containing compound.

< ion (A) >

The chemical conversion treatment agent of the present embodiment contains an ion (a) (hereinafter, also simply referred to as an ion (a)) containing a metal element selected from zirconium, titanium, and hafnium. Examples of the ion (a) include: metal ions of zirconium, titanium or hafnium; complex ions comprising zirconium, titanium or hafnium; oxide ions of zirconium, titanium or hafnium, and the like. One or two or more of these ions may be contained in the chemical conversion treatment agent.

The concentration of the ion (a) in the chemical conversion treatment agent is not particularly limited, and is usually 5mg/L or more, preferably 20mg/L or more, and is usually 2000mg/L or less, preferably 1000mg/L or less as a metal-equivalent mass concentration (meaning a total metal-equivalent mass concentration when two or more kinds of ions (a) are contained).

The source of the ion (a) is not particularly limited as long as it is a compound capable of providing the ion (a) when mixed in an aqueous medium. Examples thereof include hexafluorozirconic acid, zirconium sulfate, zirconyl sulfate, zirconium ammonium sulfate, zirconium nitrate, zirconyl nitrate, zirconium ammonium nitrate, zirconyl acetate, zirconyl lactate, zirconium tetraacetylacetonate, zirconium tetrabutoxyacetylacetonate, zirconium nitrate, zirconium carbonate, zirconium hydroxide, zirconium oxide, hexafluorotitanic acid, titanium nitrate, titanyl nitrate, ammonium titanium nitrate, titanyl nitrate, titanium sulfate, titanyl sulfate, ammonium titanium sulfate, titanium hydroxide, titanium oxide, ammonium titanium fluoride, hexafluorohafnic acid, hafnium nitrate, hafnium oxide, and the like. When they may be in the form of a salt, they may be in the form of a salt. These supply sources may be used alone, or two or more kinds may be used in combination.

< acid dye (D) >

The chemical conversion treatment agent of the present embodiment contains an acid dye (D). The "acid dye" in the present specification means a water-soluble dye having an acid group and a water-soluble dye in which the acid group can react to form a salt. Examples of the acidic group include a sulfo group, a carboxyl group, a phenolic hydroxyl group, and a phosphoric acid group. The acid dye may be an acid dye having one or two or more acid groups. Examples of the salt include: an alkali metal salt; an alkaline earth metal salt; an ammonium salt; and salts with metal elements such as aluminum, tin, chromium, copper, cobalt, nickel, and iron. The "water-soluble dye" means a dye which is dissolved in 100g of water at 20 ℃ by 0.01g or more. Further, it is preferable to dissolve 0.02g or more of the dye in 100g of water at 20 ℃ and more preferably 0.2g or more of the dye. The acid dye may be dissolved in any form in the aqueous medium, and may be in an unionized form, a form in which a part or all of the functional groups are ionized, a form in which a complex is ionized, or other forms, for example. One or two or more of these acid dyes may be contained in the chemical conversion treatment agent.

By blending the acid dye (D) into the chemical conversion treatment agent, a colored chemical conversion coating film can be formed on the surface or on the surface of the metal material. The chemical conversion coating film has excellent corrosion resistance as compared with a chemical conversion coating film formed using a chemical conversion treatment agent not containing the acid dye (D).

The amount (concentration) of the acid dye (D) to be incorporated in the chemical conversion agent is not particularly limited, but is usually 200mg/L or more, and is usually 30000mg/L or less, preferably 10000mg/L or less, and more preferably 2000mg or less.

The acid dye (D) is not particularly limited as long as it is a known acid dye. Examples thereof include azo acid dyes, triarylmethane acid dyes, indigo acid dyes, anthraquinone acid dyes, xanthene acid dyes, quinoline acid dyes, nitro acid dyes, and cyanine acid dyes. These may be used singly or in combination of two or more, and in the case of using two or more in combination, they may be combined arbitrarily. Specific examples of the acid dye (D) include those having the color index names food red 1, food red 6, acid red 1, acid red 2, acid red 9, acid red 13, acid red 18, acid red 26, acid red 27, acid red 29, acid red 33, acid red 51, acid red 52, acid red 60, acid red 73, acid red 87, acid red 88, acid red 91, acid red 92, acid red 94, acid red 95, acid red 112, acid red 114, acid red 289, acid violet 9, acid violet 43, acid orange 7, acid orange 20, acid orange 24, acid yellow 1, acid yellow 3, acid yellow 11, acid yellow 23, acid yellow 36, acid yellow 40, acid yellow 73, food yellow 3, food green, acid green 25, acid green 5, acid green 1, acid green 3, food blue 2, acid blue 3, acid blue 5, acid blue 9, acid blue 74, acid blue 9, and acid blue 5, Direct blue 1, direct blue 2, direct blue 6, direct blue 14, reactive blue 21, acid black 1, and the like.

< ion (B) >

The chemical conversion treatment agent of the present embodiment contains an ion (B) (hereinafter, also simply referred to as an ion (B)) containing a metal element selected from chromium, iron, cobalt, vanadium, and copper. Examples of the ion (B) include: metal ions of chromium, iron, cobalt, vanadium or copper; complex ions comprising chromium, iron, cobalt, vanadium or copper; oxide ions of vanadium, and the like. One or two or more of these ions may be contained in the chemical conversion treatment agent.

The concentration of the ion (B) in the chemical conversion treatment agent is not particularly limited, and is usually 5mg/L or more, preferably 20mg/L or more, and is usually 2000mg/L or less, preferably 1000mg/L or less, as the metal-equivalent mass concentration (meaning the total metal-equivalent mass concentration when two or more kinds of ions (B) are contained).

The source of the ion (B) is not particularly limited as long as it is a compound capable of providing the ion (B) when mixed in an aqueous medium. Examples thereof include: chromium (III) fluoride, chromium (III) phosphate, chromium (III) nitrate, chromium (III) sulfate, chromium (III) chloride, chromium (III) acetate, chromium (III) oxalate, chromium (III) succinate; iron (II) fluoride, iron (III) fluoride, iron (II) hydroxide, iron (III) hydroxide, iron (II) nitrate, iron (III) acetylacetonate, iron (II) chloride, iron (III) citrate, iron (II) oxide, iron (III) oxide, iron (II) hexacyanide, iron (III) hexacyanide, iron (II) hexacyanide acid, iron (III) hexacyanide potassium, iron (II) ammonium sulfate, iron (III) ammonium sulfate, iron (II) phosphate; cobalt fluoride, cobalt sulfate, cobalt nitrate, cobalt acetate, cobalt carbonate, cobalt phosphate and cobalt chloride; vanadium (II) oxide, vanadium (IV) oxide, vanadium (V) oxide, sodium metavanadate, potassium metavanadate, ammonium metavanadate, vanadium bisacetylacetonate, vanadyl diacetylacetonate, vanadium fluoride, vanadium phosphate, vanadyl sulfate, vanadium sulfide, vanadyl oxalate, triisopropoxytovanadioxide, vanadium tributoxide, vanadium triethoxy oxide, triisobutoxyvanadium oxide, vanadium triethanolamine oxide, ammonium vanadyl citrate oxide, vanadium tributoxide stearate, vanadyl acetylacetonate, vanadium tetrapropoxide, vanadium tetrabutoxide; copper nitrate, copper sulfate, copper chloride, copper oxide, copper fluoride, and the like. When they can take the form of salts, they may be salts thereof. These supply sources may be used alone, or two or more kinds may be used in combination. Wherein the source of the ion (B) is a compound different from the acid dye (D).

< fluorine-containing ion (C) >)

The chemical conversion treatment agent of the present embodiment contains an ion (C) containing fluorine (hereinafter, also simply referred to as ion (C)). Examples of the ion (C) include: fluoride ions; ions that bond or coordinate with metal ions present in the chemical conversion treatment agent, and the like. One or two or more of these ions may be contained in the chemical conversion treatment agent.

The concentration of the ion (C) in the chemical conversion agent may be 6 times or more the molar concentration of the total metal of zirconium, titanium and hafnium in terms of fluorine, and the upper limit is preferably 200 times or less.

The source of the ion (C) is not particularly limited as long as it is a compound capable of providing the ion (C) when mixed in an aqueous medium. Examples thereof include: fluorine-containing compounds such as hydrofluoric acid, ammonium fluoride, ammonium bifluoride, germanium fluoride, aluminum fluoride, potassium bifluoride, sodium fluoride, and sodium hydrogen fluoride. Further, the ion source may be supplied only with a supply source of plasma (a) such as hexafluorozirconic acid, hexafluorotitanic acid, or hexafluorohafnic acid (also belonging to a fluorine-containing compound), may be supplied only with a supply source of plasma (B) such as chromium (III) fluoride, iron (II) fluoride, iron (III) fluoride, cobalt fluoride, vanadium fluoride, or copper fluoride (also belonging to a fluorine-containing compound), may be supplied with a supply source of ion (a) and a supply source of ion (B), may be supplied with a fluorine-containing compound other than a supply source of ion (a) and a supply source of ion (B), or may be supplied with a supply source of complex ion (a) and/or a supply source of ion (B) and a fluorine-containing compound other than these. In addition, when a chemical conversion treatment agent is produced using a compound containing zirconium, titanium or hafnium, and fluorine, such as hexafluorozirconic acid, hexafluorotitanic acid, and hexafluorohafnic acid, the ion (a) and the ion (C) can be supplied. In addition, when the chemical conversion treatment agent is produced using a compound containing chromium, iron, cobalt, vanadium, or copper, and fluorine, such as chromium (III) fluoride, iron (II) fluoride, iron (III) fluoride, cobalt fluoride, vanadium fluoride, or copper fluoride, the ion (B) and the ion (C) can be supplied. In addition, only one kind of each of the fluorine-containing compounds may be used, or two or more kinds thereof may be used in combination.

< aqueous Medium >

The aqueous medium is not particularly limited as long as it is water or a mixture of water and a water-miscible organic solvent (a mixture containing 50% by volume or more of water based on the volume of the aqueous medium). The water-miscible organic solvent is not particularly limited as long as it is an organic solvent miscible with water, and examples thereof include: ketone solvents such as acetone and methyl ethyl ketone; amide solvents such as N, N' -dimethylformamide and dimethylacetamide; alcohol solvents such as methanol, ethanol, and isopropanol; ether solvents such as ethylene glycol monobutyl ether and ethylene glycol monohexyl ether; pyrrolidone-based solvents such as 1-methyl-2-pyrrolidone and 1-ethyl-2-pyrrolidone. These water-miscible organic solvents may be mixed with water alone or in combination of two or more kinds.

< other ingredients >

Examples of other components include: known additives for chemical conversion treatment agents, such as a source (E) for supplying ions of a metal selected from aluminum, magnesium, and zinc, a source (F) for supplying nitrate ions, a surfactant for adjusting wettability of a treated object, a surfactant called an antifoaming agent, and a pH adjuster; examples of the resin include known water-soluble resins and water-dispersible resins such as acrylic resins, polyester resins, epoxy resins, polyolefin resins, phenolic resins, polyvinyl resins, polyurethane resins, polyimide resins, and polyamide resins, but are not limited thereto. These other components may be contained within a range not impairing the effects of the present invention.

< pH of chemical conversion treating agent >

The pH of the chemical conversion treatment agent of the present embodiment is not particularly limited, and is usually in an acidic to neutral range, specifically, the pH is preferably in the range of 1.0 to 7.0, more preferably in the range of 1.5 to 6.0, and particularly preferably in the range of 2.0 to 5.5. Here, the pH value of the chemical conversion treatment agent in the present specification means a value measured at 50 ℃ using a pH meter.

The pH of the chemical conversion treatment agent may be, for example: acid components such as hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, boric acid, and organic acids; and a pH adjuster for adjusting a pH of an alkali component such as lithium hydroxide, potassium hydroxide, sodium hydroxide, calcium hydroxide, magnesium hydroxide, barium hydroxide, an alkali metal salt, ammonia, an ammonium salt, and an amine, but the pH adjuster is not limited to these components. One or two or more pH adjusting agents may be used.

< method for producing chemical conversion treating agent >

The chemical conversion treatment agent of the present embodiment can be produced by mixing a predetermined amount of the source of ion (a), the source of ion (B), the source of ion (C), and the acid dye (D) in an aqueous medium. The chemical conversion treatment agent of the present embodiment can be produced by mixing the above-mentioned raw materials in an aqueous medium in the order mentioned above, for example. In addition, when other components are blended, for example, the above-mentioned raw materials can be blended with an aqueous medium and then blended with other components.

< method for producing chemical conversion coating >

The method for producing a chemical conversion coating of the present embodiment includes a contact step of bringing the chemical conversion treatment agent of the present embodiment into contact with the surface of a metal material or on the surface. Thereby forming a chemical conversion coating on the surface of the metal material. The method of contacting the chemical conversion treatment agent with the metal material includes conventional methods such as a dipping treatment method, a spraying treatment method, a rinsing treatment method, and a combination thereof, but is not limited thereto.

The contacting step is preferably performed for a predetermined time within a predetermined temperature range. The contact temperature is preferably in the range of 10 ℃ or more and 90 ℃ or less, more preferably in the range of 20 ℃ or more and 85 ℃ or less, but is not limited to these temperature ranges. The contact time is preferably in the range of 20 to 700 seconds, more preferably in the range of 30 to 600 seconds, but is not limited to these times.

Further, the pretreatment step may be performed before the contact step. Examples of the pretreatment step include: acid washing process; a degreasing process; an alkali cleaning process; chromate chemical conversion treatment; a phosphate chemical conversion treatment step using a phosphate such as zinc phosphate or iron phosphate; a bismuth substitution plating step, a zirconium chemical conversion treatment step, a titanium chemical conversion treatment step, a hafnium chemical conversion treatment step, a vanadium chemical conversion treatment step, and the like. Among these, at least the degreasing step is preferably performed. These pretreatment steps may be performed in one step, or may be performed in sequence by combining two or more steps. The combination of two or more steps includes a phosphate chemical conversion treatment step, and a combination with a chromate chemical conversion treatment, a bismuth substitution plating step, a zirconium chemical conversion treatment step, a titanium chemical conversion treatment step, a hafnium chemical conversion treatment step, or a vanadium chemical conversion treatment step. The chemical conversion treatment agent of the present embodiment may be used in the zirconium chemical conversion treatment step performed as the pretreatment step, or a chemical conversion treatment agent different from the chemical conversion treatment agent of the present embodiment may be used. In the case of performing the various pretreatment steps, the water washing treatment step may be performed after the various pretreatment steps. When a plurality of various pretreatment steps are performed, the water washing treatment step may be performed after each step or after a part of the steps. In the case of performing the water washing treatment step, a drying step of drying the surface of the metal material may be performed thereafter.

In the method for producing a chemical conversion coating according to the present embodiment, after the contact step, a post-treatment step such as an alkali cleaning step, a water cleaning step, a chromate chemical conversion treatment, a zinc phosphate chemical conversion treatment step, a bismuth substitution plating step, a ferrophosphorus chemical conversion treatment step, a zirconium chemical conversion treatment step, a titanium chemical conversion treatment step, a hafnium chemical conversion treatment step, and a drying step may be performed. These post-treatment steps may be performed as a single step or may be performed in sequence by combining two or more steps. The chemical conversion treatment agent of the present embodiment may be used in the zirconium chemical conversion treatment step performed as the post-treatment step, or a chemical conversion treatment agent different from the chemical conversion treatment agent of the present embodiment may be used. In the case of performing the various post-treatment steps, the water washing treatment step may be performed after the various post-treatment steps. When a plurality of various post-treatment steps are performed, the water-washing treatment step may be performed after each step or after a part of the steps. In the case of performing the water washing treatment step, a drying step of drying the surface of the metal material may be performed thereafter. The drying step is usually carried out at 50 to 180 ℃, preferably 80 to 150 ℃, and is usually carried out for 5 to 20 minutes, preferably 10 to 15 minutes.

Examples of the metal material include: steel materials (e.g., cold-rolled steel sheets, hot-rolled steel sheets, high-tensile steel sheets, tool steels, alloy tool steels, spheroidal graphite cast irons, gray cast irons, etc.); plating materials such as zinc-plated materials (e.g., electrogalvanizing, hot-dip galvanizing, etc.), zinc-alloy-plated materials (e.g., alloyed hot-dip galvanizing, Zn — Al alloy plating, Zn — Al — Mg alloy plating, electrogalvanizing, etc.), aluminum-plated materials, and the like; an aluminum material or an aluminum alloy material (for example, 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, 7000 series, aluminum casting, aluminum alloy casting, die casting material, etc.); a magnesium material or a magnesium alloy material; a zinc material or a zinc alloy material; a copper material or a copper alloy material; a chromium material or a chromium alloy material; a nickel material or a nickel alloy material; a tin material or a tin alloy material, etc.

The metal material having a chemical conversion coating film of the present embodiment is a metal material having a surface or a surface on which the chemical conversion treatment agent of the present embodiment is brought into contactA chemical conversion coating film is produced. In the chemical conversion coating produced, the total mass per unit area of zirconium, titanium, hafnium, chromium, iron, cobalt, vanadium and copper contained in the chemical conversion coating is preferably 5mg/m²Above, more preferably 10mg/m²Above, 20mg/m is particularly preferable²The above. The upper limit is not particularly limited, but is preferably 200mg/m²The following. The mass of zirconium, titanium, hafnium, chromium, iron, cobalt, vanadium, and copper in the chemical conversion coating can be measured by using, for example, a fluorescent X-ray analyzer.

In the produced chemical conversion coating, the total carbon-equivalent mass per unit area of the acid dye contained in the chemical conversion coating (hereinafter, simply referred to as the dye deposition amount) is preferably 10mg/m²Above, more preferably 20mg/m²Above, 50mg/m is particularly preferable²The above. The upper limit is not particularly limited, but is preferably 200mg/m²The following. The mass of the acid dye in the chemical conversion coating can be measured by using, for example, TOC (total organic carbon analyzer).

The metal material having a chemical conversion coating of the present embodiment may have one or two or more of the various coatings described above (for example, a chromate chemical conversion coating, a phosphate chemical conversion coating, a bismuth substitution plating coating, and the like) on or under the chemical conversion coating obtained by contacting the chemical conversion treatment agent of the present embodiment.

By forming a coating film by coating the surface of the metal material having a chemical conversion coating film of the present embodiment with a paint, a coated metal material having a chemical conversion coating film and a coating film can be produced. The coating material is not particularly limited, and a colored coating material may be used, or a transparent coating material may be used so as not to change the color imparted by the acid dye (D). The coating method is not particularly limited, and known methods such as a roll coating method, a flow dip coating method, an electrostatic powder coating method, an electrodeposition coating method, and a solvent coating method can be applied. The laminate film may be attached by a dry lamination method, an extrusion lamination method, or the like. The coated metal material may have a coating film on the surface of the metal material having the chemical conversion coating of the present embodiment, or may have a coating film on the surface of one or two or more of the various coatings (for example, a chromate chemical conversion coating, a phosphate chemical conversion coating, a bismuth substitution plating coating, a vanadium chemical conversion coating, and the like) further formed on the chemical conversion coating. The coating film may be composed of 1 layer or 2 or more layers. The thickness of the coating film is not particularly limited, and may be appropriately set according to the use application of the coated metal material.

Examples

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

< Metal Material >

As the metal material, JIS H4000: 2014 (A1050: thickness: 0.8mm), JIS G3302: 2010 Hot-dip galvanized steel sheet (GI: thickness: 0.6mm, plating adhesion amount: 50g/m on one side)²) JIS G3321: 2012 aluminum-zinc hot-dip coated steel sheet (GL: thickness: 0.4mm, plating adhesion amount: 75g/m on one side)²) JIS G3313: the electrogalvanized steel sheet (EG: thickness 0.8mm, plating adhesion: 45g/m on one side)²) The cut pieces were 150mm in length by 70mm in width.

< Components for the preparation of chemical conversion treating agent >

In the production of the chemical conversion treatment agent, as a supply source of the ion (a), a 1: hexafluorozirconic acid (seitan chemical industries, ltd.), a 2: zirconium sulfate (japanese light metal co., ltd.), or a 3: titanium ammonium fluoride (sentan chemical industries co.); as a supply source of the ions (B), B1: chromium nitrate (japan chemical industry co., ltd.), B2: chromium sulfate (japan chemical industry co., ltd.), B3: iron nitrate (fuji film and guoki), B4: copper sulfate (fuji film and Wako pure chemical industries, Ltd.); as a supply source of the ions (C), C1: hydrofluoric acid (sentan chemical industries), C2: aluminum fluoride (seitan chemical industry co.); as dye (D), D1: food yellow No.5 (tokyo chemical industry co., ltd.; food yellow 3), D2: acid yellow 23 (tokyo chemical industry co., ltd), D3: acid red 27 (tokyo chemical industry co., ltd), D4: acid blue 74 (tokyo chemical industry co., ltd), D5: acid blue 9 (tokyo chemical industry co., ltd), D6: acid dye of reactive turquoise blue g (n) (sumitomo chemical corporation; reactive blue 21), D7: alkali blue 9 (fuji film and mitsubishi koku corporation), D8: basic violet 10 (fuji film and mitsubishi koku corporation), D9: basic violet 3 (fuji film and mitsubishi co). In addition, the above-mentioned a1 and A3 also serve as a supply source of the ions (C).

< preparation of chemical conversion treating agent >

As shown in Table 1, chemical conversion treatment agents of examples 1 to 21 and comparative examples 1 to 8 were prepared by mixing predetermined amounts of the respective components in water and adjusting the pH to a predetermined value with ammonia.

Production of Metal Material having chemical conversion coating

Various metal materials (A1050, GI, GL, and EG) were immersed in a degreasing agent (FC-4424; JAPONICA Rice-flour-noodles, Japan; an aqueous solution dissolved in water to a concentration of 20 g/L) for 120 seconds to degrease the metal materials. Thereafter, spray washing was performed for 30 seconds. Next, a metal material was immersed in each of the chemical conversion treatment agents (the chemical conversion treatment agents of examples 1 to 21 and comparative examples 1 to 8) under the conditions shown in table 1, and a chemical conversion coating film was produced on the surface of the metal material or on the surface of the metal material. The surface of the obtained metal material having the chemical conversion coating was washed with tap water and deionized water in this order, and dried at 150 ℃ for 10 minutes to obtain a test sheet.

[ Table 1]

< evaluation of Properties >

The test plate thus produced was used to evaluate the following properties. The results are shown in Table 2.

(1) Amount of adhesion

The amount of the chemical conversion coating deposited (the total amount of all metals deposited) on the test plate thus produced was measured for the total mass of all zirconium, titanium, chromium, iron and copper contained in the chemical conversion coating using a scanning fluorescent X-ray analyzer zsxprimus ii manufactured by Rigaku co. The dye deposition amount was determined by conversion of the total organic carbon amount measured by a total organic carbon analyzer TOC-LCSH manufactured by Shimadzu corporation.

(2) Colorability

The produced test plate was visually checked for coloring.

< decision reference >

Coloring was observed.

N. No coloration was observed.

(3) Corrosion resistance

Corrosion resistance of each test panel was measured according to JIS Z2371: 2015, a neutral salt spray test was performed, and the time until the area of rust generated reached 10% was measured for the evaluation surface having a chemical conversion coating. The rust area in the evaluation surface having the chemical conversion coating was a total area of rust portions measured and visually confirmed.

(4) Acid resistance

Each test plate was immersed in an aqueous nitric acid solution (25 ℃ C.) having a pH adjusted to 2 for 5 minutes, and whether or not the chemical conversion coating was discolored was visually checked, and the acid resistance (aqueous nitric acid solution) was evaluated according to the following evaluation criteria.

< evaluation Standard >

Y. non-fading

N. color fading

Each test panel on which the chemical conversion coating was formed as described above using the chemical conversion treatment agent of example 4 or 15 was immersed in a 5% or 10% aqueous acetic acid solution or a 5% or 10% aqueous citric acid solution (each at 25 ℃) for 5 minutes, and whether or not the chemical conversion coating was discolored was visually observed, and the evaluation was performed according to the same evaluation criteria. As a result, no discoloration was observed in any of the aqueous solutions. In addition, the results of acid resistance evaluation using acetic acid and citric acid are not shown in table 2.

(5) Alkali resistance

Each test plate was immersed in an aqueous sodium hydroxide solution (25 ℃) adjusted to pH 12 for 5 minutes, and whether or not the chemical conversion coating was discolored was visually observed to evaluate.

< evaluation Standard >

Y. non-fading

N. color fading

[ Table 2]

As shown in Table 2, when the chemical conversion treatment agents of examples (examples 1 to 21) were used, a colored chemical conversion coating having more excellent corrosion resistance could be formed on the surface of the metal material or on the surface thereof, as compared with the chemical conversion treatment agents of comparative examples (comparative examples 1 to 8). The chemical conversion coating film is excellent in acid resistance and alkali resistance. Further, when the chemical conversion treatment agent of the present embodiment is used, the color tone of the chemical conversion coating (the difference between the color tone of the metal material before the chemical conversion coating is formed and the color tone of the metal material after the chemical conversion coating is formed: color difference) and the amount of the chemical conversion coating deposited show a correlation. That is, the amount of the chemical conversion coating deposited can be controlled by visually checking the color tone of the chemical conversion coating. Further, a chemical conversion coating having no color unevenness and a uniform deposition amount can be formed on the surface or the surface of the metal material.

While the present invention has been described in detail and with reference to specific examples thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.