KR101935079B1

KR101935079B1 - Chemical conversion coating agent

Info

Publication number: KR101935079B1
Application number: KR1020147009648A
Authority: KR
Inventors: 스스무 마에카와; 데루조 도이; 게이타 우치카와; 다카유키 우에노
Original assignee: 니뽄 페인트 서프 케미컬즈 컴퍼니 리미티드
Priority date: 2011-10-14
Filing date: 2012-10-12
Publication date: 2019-01-03
Also published as: JP6063701B2; KR20140075722A; JP2013100600A; TW201333264A; CN103958737A; WO2013054904A1

Abstract

The present invention relates to a method for producing a fluorine-containing silane coupling agent comprising one or more metal elements (A) selected from the group consisting of zirconium, titanium and hafnium, fluorine (B) (C / D) of the coupling agent (C) to the amino group-containing water-soluble organic compound (D) is in the range of 1 - 15 It is possible to form a coated surface excellent in corrosion resistance and coating film adhesion, smooth on the surface-treated surface and excellent in appearance as a chemical conversion agent for the phosphor.

Description

{CHEMICAL CONVERSION COATING AGENT}

TECHNICAL FIELD [0001] The present invention relates to a chemical conversion agent for performing a surface treatment on a substrate (coating object) before coating.

When the surface of a metal substrate is coated with an electrodeposition coating or a powder coating, a chemical coating film is chemically applied to the surface of the metal substrate before the coating process, usually for the purpose of improving the corrosion resistance, Is formed.

Conventionally, as a chemical conversion agent used in this chemical conversion treatment, a chromate chemical conversion treatment agent and a zinc phosphate chemical conversion treatment agent are widely used. However, since the chromate-based chemical conversion treatment agent contains chromium, there is a possibility that the burden on the environment is reduced, and the phosphorus oxychlorination treatment agent contains phosphoric acid ions, which may cause eutrophication of rivers and oceans.

Therefore, a chemical conversion treatment agent containing at least one of zirconium, titanium, and hafnium has attracted attention as a chemical conversion treatment agent replacing these chromate chemical conversion treatment agents and zinc phosphate chemical conversion treatment agents.

For example, Patent Document 1 discloses a chemical conversion treatment agent comprising at least one kind selected from the group consisting of zirconium, titanium and hafnium, fluorine, and an amino group-containing silane coupling agent.

Patent Document 2 describes a chemical conversion treatment agent composed of at least one member selected from the group consisting of zirconium, titanium and hafnium, fluorine, and water-soluble resin, and the water-soluble resin is a polyvinylamine resin and / or polyallylamine.

Patent Document 3 discloses a fluorine-containing resin composition comprising at least one selected from the group consisting of zirconium, titanium and hafnium, fluorine, an adhesion-imparting agent, and a chemical reaction promoter, wherein the adhesion-imparting agent is a water-soluble resin, At least one kind of chemical conversion treatment agent selected from the group consisting of In Patent Document 3, polyvinylamine resin or polyallylamine resin is exemplified as the water-soluble resin, and an amino silane coupling agent having an amino group as a silane coupling agent is exemplified.

Japanese Patent Application Laid-Open No. 2004-218070 Japanese Patent No. 4276530 Japanese Patent Application Laid-Open No. 2004-218075

A chemical conversion treatment agent containing at least one kind of zirconium, titanium and hafnium (hereinafter sometimes referred to as a chemical conversion treatment agent containing zirconium or the like) as in Patent Documents 1 to 3 is formed by a conventional phosphorus oxychlorination treatment agent Compared with the chemical conversion coating, there is a possibility that the formed chemical conversion coating film has a small film thickness, so that the insulation property is insufficient, and a smooth chemical conversion coating surface and excellent appearance can not be formed. Therefore, it is desired that the chemical conversion treatment agent containing zirconium or the like is capable of forming a coating surface which is excellent in corrosion resistance and coating film adhesion, and is smooth on the chemical conversion coating surface and excellent in appearance.

However, in Patent Documents 1 to 3, the appearance of the coating surface formed on the chemically treated surface is not sufficiently examined. Also, in Patent Documents 1 to 3, the content ratio of the amino group-containing silane coupling agent and polyallylamine or the like has not been sufficiently studied.

That is, in Patent Documents 1 and 2, no examination has been made on the appearance of the paint surface formed on the converted surface. Patent Document 1 discloses that an amino group-containing silane coupling agent is contained in a chemical conversion agent, but there is no description that a polyvinylamine resin or a polyallylamine resin is further contained. On the other hand, Patent Document 2 discloses that a chemical agent such as polyvinylamine resin or polyallylamine resin is contained in the chemical conversion treatment agent, but there is no description of addition of an amino group-containing silane coupling agent.

Further, in Patent Document 3, the appearance of the chemical conversion coating itself has been studied, but the appearance of the coating surface formed thereon has not been studied. In Patent Document 3, the polyvinylamine resin and the polyallylamine resin and the amino silane coupling agent are handled in the same manner, and the relation between the content ratio of the resin and the coupling agent and the appearance of the coating surface is not mentioned.

It is an object of the present invention to provide a chemical conversion treatment agent which is excellent in corrosion resistance and film adhesion, and which is capable of forming a coated surface having a smooth surface and excellent appearance.

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted intensive research to achieve the above object and as a result have found that at least one metal element component selected from the group consisting of zirconium, titanium and hafnium, fluorine, a silane coupling agent containing an amino group, , It has been found that the object can be attained by setting the content ratio of the amino group-containing water-soluble organic compound and the amino group-containing silane coupling agent within a predetermined range.

The present invention has been completed based on this finding.

That is,

(A), fluorine (B), an amino group-containing silane coupling agent, a hydrolyzate thereof, and a polymer thereof, selected from the group consisting of zirconium, titanium and hafnium Wherein the amino group-containing water-soluble organic compound (D) comprises at least two kinds of coupling agents (C) and an amino group-containing water-soluble organic compound (D) (C) with respect to the amino group-containing water-soluble organic compound (D), wherein the coupling agent is at least one selected from the group consisting of amines, amino group-containing organic sulfonic acid compounds, amino group-containing water-soluble epoxy compounds, (C / D) of 1 to 15 in terms of mass ratio (C / D).

According to the present invention, it is possible to provide a chemical conversion treatment agent capable of forming a coated surface which is excellent in corrosion resistance and coating film adhesion, smooth on the surface to be treated, and excellent in appearance.

The chemical conversion treatment agent of the present invention is a chemical treatment agent comprising at least one metal element (A) selected from the group consisting of zirconium, titanium and hafnium, fluorine (B), an amino group-containing silane coupling agent, a hydrolyzate thereof, (C) and the amino group-containing water-soluble organic compound (D), wherein the mass ratio of the coupling agent (C) to the amino group-containing water-soluble organic compound (D) C / D) is from 1 to 15.

The chemical conversion treatment agent of the present invention is to form a coated surface which is excellent in corrosion resistance and coating film adhesion, smooth on the surface-treated surface, and excellent in appearance by, for example, setting the mass ratio (C / D) It is possible.

Next, each component of the chemical conversion treatment agent of the present invention will be described. On the other hand, when the metal element A is referred to as the component (A), the fluorine (B) is referred to as the component (B), the coupling agent (C) D), and the metal element (E) to be described later is referred to as component (E).

[Metal element (A)]

The chemical conversion agent of the present invention comprises one or more metal elements (A) selected from the group consisting of zirconium, titanium and hafnium. These metal elements (A) are components forming a chemical conversion film, and a chemical conversion film containing the metal element (A) is formed on the base, thereby improving the corrosion resistance and abrasion resistance of the base, Can be increased. The metal element (A) preferably contains zirconium, more preferably zirconium.

The source of the zirconium is not particularly limited, and examples thereof include alkali metal fluorozirconates such as K ₂ ZrF ₆ ; (NH ₄ ) ₂ ZrF ₆ ; Soluble fluorozirconates such as fluorozirconate acids such as H ₂ ZrF ₆ and the like; Zirconium fluoride; Zirconium oxide; Zirconium nitrate, and the like.

The source of the titanium is not particularly limited, and examples thereof include alkali metal fluorotitanate, fluorotitanate such as (NH ₄ ) ₂ TiF ₆ ; Soluble fluorotitanate such as fluorotitanate acid such as H ₂ TiF ₆ ; Titanium fluoride; Titanium oxide and the like.

The source of the hafnium is not particularly limited, and for example, a fluorophthalate such as HHfF; Hafnium fluoride, and the like.

As the supply source of the metal element (A), a compound having at least one element selected from the group consisting of ZrF ₆ ² ^- , TiF ₆ ^2- and HfF ₆ ² ^- is preferable because of high film forming ability.

The content of the metal element (A) in the chemical conversion treatment agent is preferably in the range of the lower limit of 50 mass ppm and the upper limit of 2000 mass ppm, in terms of metal, relative to the total amount of the chemical conversion treatment agent. The metal element (A) does not inhibit the precipitation of the coupling agent (C) and the amino group-containing water-soluble organic compound (D) at the time of chemical conversion treatment, Adhesion and wear resistance can be improved. The lower limit is more preferably 80 mass ppm, more preferably 90 mass ppm. The upper limit is more preferably 1000 ppm by mass, still more preferably 600 ppm by mass, particularly preferably 500 ppm by mass, particularly preferably 250 ppm by mass.

[Fluorine (B)]

The fluorine (B) contained in the chemical conversion agent serves as an etching agent for the substrate. The source of the fluorine (B) is not particularly limited, and examples thereof include a compound of the metal element (A) having fluorine and a fluorine compound. Specific examples of the compound of the metal element (A) having fluorine include alkali metal fluorozirconates such as K ₂ ZrF ₆ ; (NH ₄ ) ₂ ZrF ₆ ; Soluble fluorozirconates such as fluorozirconate acids such as H ₂ ZrF ₆ and the like; Zirconium fluoride; Alkali metal fluorotitanate, fluorotitanate such as (NH ₄ ) ₂ TiF ₆ ; Soluble fluorotitanate such as fluorotitanate acid such as H ₂ TiF ₆ ; Titanium fluoride; Fluorophthalic acid such as HHfF; And hafnium compounds such as hafnium fluoride. On the other hand, when a compound of the metal element (A) having fluorine is used, fluorine ions are supplied from the compound of the metal element (A), so that fluorine compounds may not be used separately. Specific examples of the fluorine compound include fluorides such as hydrofluoric acid, ammonium fluoride, boron fluoride, ammonium hydrogen fluoride, sodium fluoride, sodium hydrogen fluoride and the like. Specific examples of the fluorocarbons include hexafluorosilicate. Specific examples of the fluorocarbons include hydrofluorosilicic acid, zinc hydrogencarbonate, manganese hydrofluoride, magnesium hydrofluoric acid, nickel hydrogencarbonate, And calcium hydrofluoride.

The content of the fluorine (B) in the chemical conversion treatment agent is preferably in the range of the lower limit of 25 mass ppm and the upper limit of 12500 mass ppm. If the lower limit is more than the lower limit, sufficient etching is obtained and a good film is obtained. If the upper limit is not exceeded, it is prevented that the etching reaction becomes excessive and the chemical reaction does not proceed sufficiently. The lower limit is more preferably 60 mass ppm, more preferably 100 mass ppm. The upper limit is more preferably 2500 mass ppm, more preferably 600 mass ppm.

[Coupling agent (C)]

The coupling agent (C) contained in the chemical conversion agent is one or more selected from the group consisting of an amino group-containing silane coupling agent, a hydrolyzate thereof and a polymer thereof. The amino group-containing silane coupling agent is a compound having at least one amino group in the molecule and having a siloxane bond. The adhesion of the amino group-containing silane coupling agent, the hydrolyzate thereof and the polymeric compound thereof to one or more selected from the group consisting of the silane coupling agent, the hydrolyzate thereof and the polymeric compound thereof is improved by the action of both the chemical conversion coating and the coating film.

It is presumed that such an effect is caused by the fact that the group formed by the hydrolysis and the silanol generation is hydrolyzed and adsorbed on the surface of the metal base material and the metal element (A) in a hydrogen bonding manner to increase the adhesion between the chemical conversion film and the metal base material. As described above, one or two or more kinds selected from the group consisting of an amino group-containing silane coupling agent, a hydrolyzate thereof and a polymer thereof contained in the chemical conversion coating act on both the metal base and the coating film, And the like.

The amino group-containing silane coupling agent is not particularly limited, and examples thereof include N-2 (aminoethyl) 3-aminopropylmethyldimethoxysilane, N-2 (aminoethyl) 3-aminopropyltrimethoxysilane, N Aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3- Containing silyl groups such as N, N-bis [3- (trimethoxysilyl) propyl] ethylenediamine, etc., Coupling agents and the like. KBM-603, KBE-603, KBM-903, KBE-9103 and KBM-573 (manufactured by Shin-Etsu Chemical Co., Ltd.) and XS1003 (manufactured by Chisso Corporation), which are commercially available amino group-containing silane coupling agents Can be used.

The hydrolyzate of the amino group-containing silane coupling agent can be produced by a conventionally known method such as a method of dissolving the amino group-containing silane coupling agent in ion-exchanged water and acidifying it with an optional acid. As a hydrolyzate of the amino group-containing silane coupling agent, commercially available products such as KBP-90 (Shin-Etsu Chemical Industry Co., Ltd .: 32% active ingredient) may be used.

The polymer of the amino group-containing silane coupling agent can be produced by a conventionally known method, for example, a method of reacting two or more amino group-containing silane coupling agents in an aqueous solution.

The content of the silane coupling agent (C) in the chemical conversion treatment agent is preferably in the range of the lower limit of 5 mass ppm and the upper limit of 1000 mass ppm as the solid content concentration. In other words, the content of the solid content of the silane coupling agent (C) in the total amount of the chemical conversion agent is preferably within the range of the lower limit of 5 mass ppm and the upper limit of 1000 mass ppm. If it is 5 ppm by mass or more, adhesion with the metal base material can be obtained. When it is 1000 mass ppm or less, the corrosion resistance can be improved without inhibiting the precipitation of the metal element (A) during the chemical conversion treatment. The lower limit is more preferably 10 mass ppm, more preferably 50 mass ppm, and particularly preferably 90 mass ppm. The upper limit is more preferably 750 ppm by mass, still more preferably 500 ppm by mass, and particularly preferably 300 ppm by mass.

[Amino group-containing water-soluble organic compound (D)]

The amino group-containing water-soluble organic compound (D) contained in the chemical conversion treatment agent may be at least one selected from amino acids, polyamino acids, polyallylamine resins, allylamines, polyvinylamine resins, vinylamines, amino group-containing organic sulfonic acid compounds, And an amino group-containing water-soluble phenol compound. The water-soluble organic compound containing the amino group does not contain the coupling agent (C).

It is considered that the chemical conversion coating containing the amino group-containing water-soluble organic compound (D) has high adhesion with the coating film due to the interaction of acid groups. The method for producing the amino group-containing water-soluble organic compound (D) is not particularly limited, and can be produced by a known method.

The amino group-containing water-soluble organic compound (D) is more preferably an amino acid, a polyamino acid, a polyallylamine resin, an allylamine, a polyvinylamine resin, and a vinylamine from the viewpoint of an excellent adhesion improving effect and a smoothness improving effect of a coating film.

The amino acid is not particularly limited and a commercially available amino acid such as glycine, alanine, valine, leucine, aspartic acid, glutamic acid, lysine, arginine, phenylalanine, tyrosine, cysteine, cystine, serine, threonine, histidine, tryptophan, .

The polyallylamine resin is not particularly limited, and for example, commercially available polyallylamine resins such as PAA-01, PAA-10C, PAA-H-10C and PAA-D11HCl (all available from Nitto Corporation) can be used. The polyvinylamine resin is not particularly limited, and a commercially available polyvinylamine resin such as PVAM-0595B (manufactured by Mitsubishi Chemical Corporation) can be used. As the allylamines, allylamine, diallylamine, triallylamine and the like can be used. Examples of the vinyl amines include dimethyl acrylamide, dimethylaminoethyl acrylate, and dimethylaminopropylacrylamide. Two or more of these may be used in combination.

When amino acids, polyallylamine resins, allylamines, polyvinylamine resins, and vinyl amines are used, the paintability and corrosion resistance of the metal substrate after the surface treatment can be improved. The reason is as follows.

The chemical conversion film component composed solely of the metal element (A) is weak in bonding and has poor adhesion to the steel sheet and the coating material. In addition, the chemical conversion coating composition tends to have poor adhesion due to cracking in the coating itself due to cohesive failure caused by volumetric shrinkage during drying. When the amino acid, polyallylamine resin, allylamine, polyvinylamine resin and vinyl amines are used, the amino group in the resin adsorbs and bonds to the steel sheet and the coating film, so that the adhesion becomes stronger. In addition, adhesion is improved by stress relaxation caused by the resin entering the coating. Further, by improving the insulating property of the formed chemical film to be formed, it is possible to form a coated surface excellent in appearance and smooth on the chemical conversion coating surface, particularly by promoting the formation of the coating film resistance in the electrodeposition coating.

In view of the above, the amino group-containing water-soluble organic compound (D) is preferably at least one of a polyallylamine resin and a polyvinylamine resin, more preferably a polyallylamine resin, Is more preferable.

It is preferable that the content of the compound (D) is contained in a solid content concentration within a range of a lower limit of 0.1 mass ppm and an upper limit of 10,000 mass ppm. In other words, the content of the solid content of the compound (D) in the total amount of the chemical conversion treatment agent is preferably within a range of the lower limit of 0.1 mass ppm and the upper limit of 10000 mass ppm. When the content is 0.1 mass ppm or more, the effect of improving the coating film adhesion and the appearance of the coating film can be sufficiently obtained. When the content is 10,000 mass ppm or less, inhibition of the precipitation of the metal element (A) during the chemical conversion treatment is suppressed. The lower limit is more preferably 1 mass ppm, more preferably 10 mass ppm, and particularly preferably 40 mass ppm. The upper limit is more preferably 1000 ppm by mass, still more preferably 300 ppm by mass, and particularly preferably 200 ppm by mass.

&Lt; Amino group-containing organic sulfonic acid compound &

As the amino group-containing organic sulfonic acid compound, at least one member selected from the group consisting of taurine, aminonaphthalene disulfonic acid and salts thereof can be used.

Use of an amino group-containing organic sulfonic acid compound can improve the paintability and corrosion resistance of the metal substrate after the surface treatment. The mechanism is not clear, but there are two reasons for this.

First, there is silica segregation or the like on the surface of a metal substrate such as a steel sheet, and the surface composition is uneven, so that there are portions that are difficult to be etched in the surface treatment. However, by adding the sulfonic acid compound, such a portion which is difficult to be etched can be etched, and as a result, it is presumed that a uniform rust-preventive film is easily formed on the surface of the substrate. That is, it is presumed that the amino group-containing organic sulfonic acid compound acts as an etching promoter.

Another problem is that during the chemical conversion treatment, the hydrogen gas, which may be generated by the chemical reaction, may interfere with the reaction at the interface, and the amino group-containing organic sulfonic acid compound may remove hydrogen gas And thus promoting the reaction.

The content of the amino group-containing organic sulfonic acid compound is preferably contained in a range of 0.1 ppm by mass to 100 ppm by mass in terms of solids concentration. When the content is 0.1 mass ppm or more, the effect of adding the sulfonic acid compound is sufficiently obtained. When the content is 10,000 ppm or less, inhibition of precipitation of the metal element (A) during the conversion treatment is suppressed. It is more preferable that the lower limit is 1 mass ppm and the lower limit is 1000 mass ppm.

&Lt; Amino group-containing water-soluble epoxy compound &

The amino group-containing water-soluble epoxy compound is not particularly limited as long as it has solubility such that the required amount can be dissolved in the chemical conversion treatment agent. The amino group is not particularly limited and includes, for example, compounds having an -NH ₂ group, a monoalkylamino group, a dialkylamino group, a monohydroxyamino group, a dihydroxyamino group, and other primary to tertiary amines.

The amino group-containing water-soluble epoxy compound may be an epoxy resin skeleton. The epoxy resin is not particularly limited, and examples thereof include epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, bisphenol A propylene oxide addition type epoxy resin, bisphenol F propylene oxide And addition type epoxy resins. Among them, bisphenol F type epoxy resin is preferable, and bisphenol F epichlorohydrin type epoxy resin is preferable.

The reaction for introducing an amino group into the epoxy resin forming the above skeleton is not particularly limited, and a method of mixing an epoxy resin and an amine compound in a solvent may, for example, be mentioned.

The above-mentioned chemical conversion agent preferably contains the amino group-containing water-soluble epoxy compound in a solid content concentration within a range of lower limit 20 mass ppm and upper limit 5000 mass ppm. If it is 20 mass ppm or more, proper coating performance is obtained in the resulting chemical conversion coating film, and if it is 5000 mass ppm or less, a chemical conversion coating film is efficiently formed. A more preferable lower limit is 50 mass ppm, and a more preferable upper limit is 1000 mass ppm.

The amino group-containing water-soluble epoxy compound preferably has an isocyanate group. By having the isocyanate group, a cross-linking reaction occurs with the epoxy compound, thereby improving the physical properties of the coating. The isocyanate group is preferably a block isocyanate group blocked with a block zero. By blocking, it can be stably incorporated in the chemical conversion agent.

The above block isocyanate group can be introduced into the epoxy compound by reacting a polyisocyanate compound in which a part of the isocyanate group is blocked with the epoxy compound. The polyisocyanate is not particularly limited and examples of the polyisocyanate include aliphatic diisocyanates such as hexamethylene diisocyanate (including trimer), tetramethylene diisocyanate, and trimethyl hexamethylene diisocyanate, Alicyclic polyisocyanates such as cyanate, isophorone diisocyanate and 4,4'-methylenebis (cyclohexylisocyanate), and alicyclic polyisocyanates such as 4,4'-diphenylmethane diisocyanate Aromatic diisocyanates such as naphthalene, tolylene diisocyanate and xylylene diisocyanate, and the like.

The blocking agent is not particularly limited, and examples thereof include monovalent alkyl (or aromatic) alcohols such as n-butanol, n-hexyl alcohol, 2-ethylhexanol, lauryl alcohol, phenol carbinol and methylphenyl carbinol; Cellosolves such as ethylene glycol monohexyl ether and ethylene glycol mono 2-ethylhexyl ether; Phenols such as phenol, para-t-butylphenol, and cresol; Oximes such as dimethyl keto oxime, methyl ethyl keto oxime, methyl isobutyl keto oxime, methyl amyl keto oxime, and cyclohexanone oxime;慣 -caprolactam, γ-butyrolactam, and the like. The block agents of oximes and lactams are more preferable from the viewpoint of resin curability because they dissociate at low temperatures.

As the amino group-containing water-soluble epoxy compound, commercially available products such as Adeka Resin EM-0436 series, Adeka Resin EM-0436F series, Adeka Resin EM0718 series (all available from Asahi Denka Kogyo) can be used.

The amino group-containing water-soluble epoxy compound may further contain a phosphorus element. It is preferable that the phosphorus is contained in the amino group-containing water-soluble epoxy compound as a phosphate ester group. The phosphoric acid ester group may be partially alkylated. The phosphoric acid ester group can be introduced into the epoxy compound by the reaction between the epoxy group and the phosphoric acid compound.

As the amino group-containing water-soluble phenol compound, commercially available products such as SUMILITE resin PR-NPK-225 series, 238 series, 246 series, 248 series, 249 series, 252 series, 260 series and 261 series (manufactured by Sumitomo Backrite) can be used.

Further, it is also possible to modify the amino group-containing water-soluble organic compound (D) by modifying a part of the amino group of the amino group-containing water-soluble organic compound (D) by acetylation or the like, Crosslinked with a crosslinking agent within a range that does not affect solubility, and the like.

The content of the amino group-containing water-soluble phenol compound in the chemical conversion treatment agent is preferably in the range of 20 mass ppm and 5000 ppm by mass of the solid content concentration lower limit. If the lower limit is not lower than the lower limit, the performance of the resulting chemical film becomes sufficient. If the upper limit is not exceeded, it is inhibited from inhibiting the precipitation of the metal element (A) during the chemical conversion treatment. The lower limit is more preferably 50 mass ppm, and the upper limit is more preferably 1000 mass ppm.

[Metal element (E)]

The chemical conversion agent may contain one or more metal elements (E) selected from the group consisting of iron, zinc, aluminum, magnesium, barium, copper, manganese, tin, strontium and calcium. By including the metal element (E), corrosion resistance and / or paintability of the coating film are improved. In particular, the smoothness of the coating film is improved by including barium. Corrosion resistance is improved by including aluminum.

The source of the metal element (E) is not particularly limited, and examples thereof include a nitrate, a sulfate, a chloride, and an acetate of the metal element (E). In particular, nitrates are preferred.

The content of the metal element (E) in the chemical conversion treatment agent is preferably in the range of the lower limit of 0.1 mass ppm and the upper limit of 5000 mass ppm. If the lower limit is not lower than the lower limit, the performance of the resulting chemical film becomes sufficient. If the upper limit is not exceeded, the precipitation of the metal element (A), the coupling agent (C) and the amino group- . The lower limit is more preferably 0.5 mass ppm, and the upper limit is more preferably 3000 mass ppm.

[Mass ratio (C / D)]

The mass ratio (C / D) of the coupling agent (C) to the amino group-containing water-soluble organic compound (D) in the chemical conversion agent is 1 to 15. When the mass ratio (C / D) is less than 1, the corrosion resistance of the coating film formed on the chemical conversion coating is lowered. When the mass ratio is larger than 15, the smoothness of the coating film formed on the chemical conversion coating is lowered. The lower limit is preferably 1.5, more preferably 2. The upper limit is preferably 10, more preferably 8.

[Mass ratio (C / A)]

The mass ratio (C / A) of the coupling agent (C) to the metal element (A) in the chemical conversion treatment agent is preferably 0.1 at the lower limit and 5 at the upper limit. When the mass ratio (C / A) is 0.1 or more, sufficient chemical film necessary for ensuring corrosion resistance is sufficiently precipitated. The lower limit is preferably 0.15, more preferably 0.2. When the mass ratio (C / A) is 5 or less, the coating film formed on the chemical conversion coating film is excellent in smoothness. The lower limit is more preferably 4, and more preferably 3.

[Molar ratio (F / Zr)]

In the case where the metal element (A) is zirconium, the molar ratio (F / Zr) of fluorine (B) to zirconium is preferably 4 To 8, and more preferably from 5 to 7.

[PH of chemical conversion agent]

The chemical conversion agent of the present invention preferably has a pH within a range of a lower limit of 1.5 and an upper limit of 6.5. If it is 1.5 or more, excessive etching is prevented, and sufficient film formation can be obtained. If it is 6.5 or less, etching is sufficient and a good film is obtained. The lower limit is more preferably 2, more preferably 2.5, and particularly preferably 3. [ The upper limit is more preferably 5.5, still more preferably 5, and particularly preferably 4.5. As pH adjusters, acidic compounds such as nitric acid and sulfuric acid, and basic compounds such as sodium hydroxide, potassium hydroxide and ammonia can be used to adjust the pH.

[Content of the components (A) to (D) and the contents of the components (A) to (E)

In the case where the chemical conversion treatment agent does not contain the component (E), the content of the components (A) to (D) in the components other than the solvent and the pH adjusting agent from the chemical conversion treatment agent is preferably, from the viewpoint of improving the corrosion resistance, , Preferably not less than 60 mass%, more preferably not less than 80 mass%, more preferably not less than 90 mass%, more preferably not less than 95 mass%, more preferably not less than 99 mass% And preferably 100% by mass.

In the case where the chemical conversion treatment agent contains the component (E), the content of the components (A) to (E) in the components other than the solvent and the pH adjuster from the chemical conversion treatment agent is preferably 60 mass% or more , More preferably 80 mass% or more, still more preferably 90 mass% or more, still more preferably 95 mass% or more, still more preferably 99 mass% or more, still more preferably 100 mass%.

[Production method of chemical conversion agent]

The chemical conversion treatment agent of the present invention is a chemical conversion treatment agent of the present invention which is obtained by adding to the water such as industrial water a water source such as the aforementioned source of the metal element (A), the source of fluorine (B), the coupling agent (C), the amino group- The metal element (E) may be suitably prepared by adding the above-mentioned source of the metal element (E) or other components and mixing them.

In this case, each component may be added to and mixed with water at the same time, or one component or plural components may be added and mixed in order. The order of addition and mixing is not particularly limited.

[How to process Mars]

The chemical conversion treatment method for the metal by the chemical conversion treatment agent is not particularly limited and can be carried out by bringing the chemical conversion treatment agent and the metal surface into contact with each other under the usual chemical treatment conditions. The chemical treatment temperature in the chemical conversion treatment is preferably within the range of the lower limit of 20 占 폚 and the upper limit of 70 占 폚. The lower limit is more preferably 30 ° C, and the upper limit is more preferably 50 ° C. It is preferable that the chemical conversion treatment time in the chemical conversion treatment is in the range of the lower limit of 5 seconds and the upper limit of 1200 seconds. The lower limit is more preferably 30 seconds, and the upper limit is more preferably 120 seconds. The chemical conversion treatment method is not particularly limited, and examples thereof include a dipping method, a spraying method and a roll coating method.

It is preferable that the surface of the surface-treated metal is subjected to a degreasing treatment and a degreasing water washing treatment before the chemical treatment with the chemical treatment agent, and a water washing treatment after the chemical treatment after the chemical treatment.

The degreasing treatment is performed to remove oil and contamination adhering to the surface of the substrate, and is usually carried out by immersing the substrate at 30 to 55 캜 for several minutes by a degreasing agent such as an unmanned and non-nitrogen degreasing cleaning liquid. It is also possible to carry out the preliminary degreasing treatment before the degreasing treatment, if desired.

The degreasing water washing treatment is carried out by spraying one or more times with a large amount of water for washing the degreasing agent after the degreasing treatment.

The post-chemical conversion water treatment is carried out one or more times in order not to adversely affect adhesion, corrosion resistance and the like after various coatings thereafter. In this case, it is preferable that the final flushing is performed with pure water. In this post-chemical conversion water treatment, either spray water or immersion water may be used, or water may be used in combination with these methods.

Further, the chemical conversion treatment using the chemical conversion treatment agent of the present invention does not need to perform the surface adjustment treatment that is considered necessary when using the zinc phosphate chemical conversion treatment agent, so that the chemical conversion treatment of the metal base can be performed with a smaller number of steps .

Although the drying step may be performed after the post-chemical conversion treatment, the drying step is not necessarily required. Even if the chemical conversion coating is applied in a wet state without performing the drying step, the performance is not affected. In the case of carrying out the drying step, it is preferable to perform the cold air drying, the hot air drying and the like. In the case of performing hot air drying, 300 DEG C or less is preferable in order to prevent decomposition of oil content.

[Metal substrate]

Examples of the metal substrate treated with the chemical conversion agent of the present invention include zinc based substrates, iron based substrates, and aluminum based substrates. An iron-based base material in which the substrate is made of zinc and / or an alloy thereof, an iron-based base material in which the base is made of iron and / or an alloy thereof, an aluminum base material in which the base is made of aluminum and / it means.

The chemical conversion treatment agent of the present invention can also be used for the chemical conversion treatment of a zinc-based substrate, an iron-based substrate, and an object made of a plurality of metal substrates in an aluminum-based substrate. For example, the chemical conversion treatment agent of the present invention can be suitably used for chemical conversion treatment of a substrate including at least a zinc based substrate.

The chemical conversion treatment agent of the present invention is preferable because it can impart sufficient film adhesion even to an iron-based base material to which a pretreatment with a chemical conversion treatment agent such as zirconium and the like has been unsuitable. Therefore, And can also be used for the chemical conversion of an object to be processed.

The zinc-based substrate is not particularly limited, and examples thereof include galvanized steel sheets, zinc-nickel plated steel sheets, zinc-iron-plated steel sheets, zinc-chromium plated steel sheets, zinc-aluminum plated steel sheets, , Galvanized steel sheets such as zinc-manganese-coated steel sheets, zinc-coated or zinc-based alloy-coated steel sheets such as hot-dip galvanized steel sheets, and the like. The iron base material is not particularly limited, and examples thereof include cold-rolled steel sheets (hereinafter sometimes referred to as SPC) and hot-rolled steel sheets. The above-mentioned aluminum base material is not particularly limited, and examples thereof include an aluminum alloy of 5000 series and an aluminum alloy of 6000 series. It is possible to simultaneously treat the zinc-based, iron-based, and aluminum-based substrates using the above-described chemical conversion agent.

In the chemical conversion coating obtained by the chemical conversion treatment agent of the present invention, the amount of the metal element (A) contained in the chemical conversion treatment agent is preferably within the range of the lower limit of 5 mg / m ² and the upper limit of 1000 mg / m ² . If it is 5 mg / m ² or more, a uniform chemical conversion film can be obtained. When it is 1000 mg / m ² or less, it is economically advantageous. The lower limit is more preferably 10 mg / m ² , and more preferably 20 mg / m ² . The upper limit is more preferably 500 mg / m ² , and more preferably 200 mg / m ² .

The coating that can be performed on the surface-treated metal formed by the chemical treatment agent of the present invention is not particularly limited, and conventionally known coating such as electrodeposition coating and powder coating can be performed. In particular, since all the metals such as iron, zinc and aluminum can be treated well, at least a part of them can be suitably used as a pretreatment for cationic electrodeposition coating of a substrate made of a ferrous base material. The cationic electrodeposition coating is not particularly limited, and a conventionally known cationic electrodeposition coating composition comprising an aminated epoxy resin, an aminated acrylic resin, a sulfonated epoxy resin or the like can be applied.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. In the examples, " part " means " part by mass " unless specifically denied, and "% " means "% by mass " unless otherwise specified.

Example 1

(70 mm x 150 mm x 0.8 mm, made by Nippon Test Panel Co., Ltd.) and a cold-rolled steel plate (SPC; SPC270D, made by Nippon Test Panel Co., Ltd., 70 mm x 150 mm x 0.8 mm), which are commercially available galvannealed galvanized steel sheets , And the surface treatment was carried out under the following conditions.

(1) degreasing treatment

And then immersed in 2% by mass of "Surf Cleaner EC92" (degreasing agent manufactured by Nippon Paint Co., Ltd.) at 40 ° C for 2 minutes.

(2) Washing after degreasing

It was sprayed with tap water for 30 seconds.

(3) Chemical treatment

5.7 g of 40% zirconium hydrofluoric acid (H ₂ ZrF ₆ ) was used as a supply source of the metal element (A) and fluorine (B) as the chemical conversion film forming components and ₁₀ ml of KBM- 2 g of an amino group-containing water-soluble (amino acid) -containing amino group was obtained by using 2 g of 603 (N-2 (aminoethyl) 3-aminopropyltrimethoxysilane (purity 100%: manufactured by Shin-Etsu Chemical Co., A chemical conversion treatment agent having the composition shown in Table 1 was prepared using 3.3 g of PAA-15C (polyallylamine resin: weight average molecular weight 15000: manufactured by Nittobo Co., Ltd.) as the organic compound (D).

The pH was adjusted to the values shown in Table 1 using nitric acid or sodium hydroxide. The temperature of the adjusted chemical conversion agent was adjusted to the value shown in Table 1, and each substrate was immersed for 10 to 120 seconds. The concentrations of the coupling agent (C) and the amino group-containing water-soluble organic compound (D) are expressed in terms of solid content.

(4) Washing treatment after chemical conversion treatment

It was sprayed with tap water for 30 seconds. And further sprayed with ion-exchanged water for 30 seconds.

(5) Drying treatment

The metal substrate after the water washing treatment was not subjected to a drying treatment, and the coating film entered the next coating process while the coating film was wet.

After treating 1 m ² of the metal base material per 1 L of the chemical conversion treatment agent, electrodeposition coating was carried out under the following conditions using "Power Float 1200" (cation electrodeposition paint, manufactured by Nippon Paint Co., Ltd.).

Voltage: 100V

Time: Start for 30 seconds, hold for 150 seconds

Temperature: 30 ℃

After washing with water, the plate was heated at 170 캜 for 20 minutes and baked to prepare a test plate.

On the other hand, the measurement results of the film thickness of the electrodeposition coating film are shown in Table 1.

&Lt; Evaluation test >

(1) Center line average roughness (Pa)

The center line average roughness (Pa) of the cross section curve of the obtained electrodeposition coating film was measured using an evaluation type surface roughness tester (SURFTEST SJ-201P, Mitsuto Corporation) according to JIS-B0601: 2001. The measurement was carried out seven times using a sample having a 2.5 mm width cutoff (number of compartments 5), and the Pa value was obtained by the vertical erasure averaging. The results are shown in Table 1.

(2) Secondary adhesion test (SDT)

The obtained test plate was immersed in an aqueous 5% NaCl solution at 50 DEG C for 840 hours. Thereafter, the cut portion was peeled off from the tape and the area (Z mm ² ) of the peeled coating film was measured. Then, two vertical parallel area in the cutting (X × Ymm ²⁾ the area of the peeling film for a (Zmm ²⁾ the area ratio (Z / (X × Y) × 100%) to produce a coating film in the following standards of Was evaluated.

5 points: area ratio less than 5%

4 points: area ratio exceeding 5% and below 20%

3 points: area ratio exceeding 20% and below 30%

2 points: area ratio exceeding 30% and less than 50%

1 point: area ratio exceeding 50%

The evaluation results are shown in Table 1.

(3) Cycle corrosion test (CCT)

The edge and back of the obtained test plate were sealed with a tape, and a cross cut scratch (a scratch with a depth reaching the metal) was put on the surface of the test plate with a cutter knife.

Subsequently, a 5 mass% NaCl aqueous solution kept at 35 캜 was continuously sprayed on the surface of the test plate containing the crosscut scratches for 2 hours, followed by drying for 4 hours under conditions of 60 캜 and humidity of 20 to 30% And allowed to stand for 2 hours under a humidified atmosphere of 50 DEG C and a humidity of 95% or more. After one hundred cycles of this cycle, the maximum value of the swelling width (one side) of the coating film from the crosscut flaws was measured.

5 points: 4mm or less on one side

4 points: One side more than 4mm and less than 6mm

3 points: One side more than 6mm and less than 8mm

2 points: One side more than 8mm and less than 10mm

1 point: more than 10mm on one side

The results are shown in Table 1.

Examples 2 to 14, Examples 17 to 18 and Comparative Examples 1 to 7

The same operation as in Example 1 was carried out except that a chemical conversion treating agent having the composition shown in Table 1 was prepared. The results are shown in Table 1.

On the other hand, each notation in the table means the following.

APS-2: KBM-903 (3-aminopropyltrimethoxysilane, 100% purity, manufactured by Shin-Etsu Chemical Co., Ltd.)

APS-3: KBP-90 (3-aminopropyltrimethoxysilane hydrolyzate, purity 32%, manufactured by Shin-Etsu Chemical Co., Ltd.)

PVA: PVAM-0595B (polyvinylamine resin, number average molecular weight: 70000, manufactured by Mitsubishi Chemical Corporation)

In addition, aluminum, magnesium and barium as the metal element (E) are respectively added as aluminum nitrate, magnesium nitrate and barium nitrate as a source. In the table, the concentration of the metal element is shown instead of the concentration of the source.

Example 15

The same operation as in Example 1 was carried out except that "(3) chemical conversion treatment" of Example 1 was changed to "(3-1) chemical conversion treatment" described below. The results are shown in Table 1.

(3-1) Chemical treatment

4.54 g of 40% zirconium hydrofluoric acid (H ₂ ZrF ₆ ) was used as a supply source of the metallic element (A) and fluorine (B) as the chemical conversion film forming components and ₁₀ g of the metallic element (A) as using a 20% ZrO ₂ containing zirconium nitrate aqueous solution of 1.35g as a source, and a coupling agent (C) KBM-603 (N -2 ( aminoethyl) 3-aminopropyl trimethoxy silane (purity: 100%: Shin-Etsu chemical Co. (Polyallylamine resin: weight-average molecular weight: 15,000, manufactured by Nitto Boseki Co., Ltd.) as an amino group-containing water-soluble organic compound (D) g, a chemical conversion treatment agent having the composition shown in Table 1 was prepared.

The pH was adjusted to the values shown in Table 1 using sodium hydroxide. The temperature of the adjusted chemical conversion agent was adjusted to the value shown in Table 1, and each substrate was immersed for 10 to 120 seconds. The concentrations of the coupling agent (C) and the amino group-containing water-soluble organic compound (D) are expressed in terms of solid content.

Example 16

The same operation as in Example 1 was carried out except that the "(3) chemical conversion treatment" of Example 1 was changed to the "(3-2) chemical conversion treatment" described below. The results are shown in Table 1.

(3-2) Chemical treatment

5.68 g of 40% zirconium hydrofluoric acid (H ₂ ZrF ₆ ) was used as a supply source of the metallic element (A) and fluorine (B) as the chemical conversion film forming components, (Aminoethyl) 3-aminopropyltrimethoxysilane (purity 100%: manufactured by Shin-Etsu Chemical Co., Ltd.) as the coupling agent (C) (Polyarylamine resin: weight-average molecular weight: 15000, manufactured by Nittobo Co., Ltd.) as an amino group-containing water-soluble organic compound (D) , A chemical conversion treating agent having the composition shown in Table 1 was prepared.

As shown in Table 1, in the chemical conversion coatings obtained by the chemical treatment agents of Examples 1 to 14 and Examples 15 to 18, the electrodeposition coating film formed on the surface thereof was small in irregularities and excellent in corrosion resistance.

On the contrary, in the chemical conversion coating film obtained by the chemical conversion treatment agent of Comparative Example 1 which does not contain the amino group-containing water-soluble organic compound (D), the electrodeposition coating film formed thereon has a large unevenness, resulting in poor appearance.

Further, in the chemical conversion coating on the SPC steel sheet obtained by the chemical conversion treatments of Comparative Examples 2 to 4 in which the mass ratio (C / D) was smaller than the range of the present invention, the electrodeposition coating film formed thereon was inferior in corrosion resistance. Further, in the chemical conversion coatings obtained by the chemical conversion treatments of Comparative Examples 2 and 3, the electrodeposited coating film formed thereon was large in unevenness, and the appearance was low.

Also in Comparative Example 5 which did not contain the coupling agent (C), the electrodeposition coating film was inferior in corrosion resistance.

On the other hand, in Comparative Example 6, which does not include the amino group-containing water-soluble organic compound (D), and Comparative Example 7 in which the mass ratio (C / D) is larger than the range of the present invention, All were uneven.

Claims

At least one metal element (A) selected from the group consisting of zirconium, titanium and hafnium,
Fluorine (B),
At least one coupling agent (C) selected from the group consisting of an amino group-containing silane coupling agent, a hydrolyzate thereof and a polymer thereof, and
The amino group-containing water-soluble organic compound (D)
Lt; / RTI >
The amino group-containing water-soluble organic compound (D) may be at least one compound selected from the group consisting of an amino acid, a polyallylamine resin, an allylamine, a polyvinylamine resin, a vinylamine, an amino group-containing organic sulfonic acid compound, And at least one kind selected from the group consisting of
Wherein the mass ratio (C / D) of the coupling agent (C) to the amino group-containing water-soluble organic compound (D) is 1 to 15 and the mass ratio of the coupling agent (C) to the metal element (A) ) Is 0.1 to 5, and is a chemical conversion treatment agent for chemical conversion of a substrate (article to be coated) containing a zinc based substrate and an iron based substrate.

The method according to claim 1,
And at least one metal element (E) selected from the group consisting of iron, zinc, aluminum, magnesium, barium, copper, manganese, tin, strontium and calcium.

The method according to claim 1,
Wherein the content of the metal element (A) is 50 to 2000 mass ppm and the content of the coupling agent (C) is 5 to 1000 mass ppm of a solid concentration.

The method according to claim 1,
A chemical conversion agent having a pH of 1.5 to 6.5.

A method for chemical conversion treatment of a substrate comprising a zinc based substrate and an iron based substrate, wherein the chemical conversion treatment agent according to any one of claims 1 to 4 is brought into contact with the surface of the substrate metal including the zinc based substrate and the iron based substrate.

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