KR20170084152A - Metal surface treatment liquid, method for producing surface-treated metal material, and surface-treated metal material - Google Patents

Abstract

The present invention provides a metal surface treatment liquid capable of obtaining a surface-treated metal material excellent in corrosion resistance, porosity, chemical resistance, coating film adhesion and corrosion resistance after coating. The metal surface treatment liquid of the present invention is characterized by comprising a block isocyanate (A) having an isocyanate group blocked by a blocking agent and having an isocyanurate structure and a polyalkyleneoxy chain, a hydroxyl group, an amino group, a sulfo group and a carboxyl group (B) having at least one functional group selected from the group consisting of an organic resin

Description

TECHNICAL FIELD [0001] The present invention relates to a metal surface treatment liquid, a method for producing a surface treatment metal material, a surface treatment metal material,

The present invention relates to a metal surface treatment liquid, a method for producing a surface-treated metal material, and a surface-treated metal material.

BACKGROUND ART [0002] In the fields of home telephone products, automobiles, building materials and the like, a technique of performing chromate treatment on a metal material such as a steel sheet for the purpose of imparting corrosion resistance or coating film adhesion is generally used. However, chromate-treated films usually contain hexavalent chromium having a high environmental load. Recently, there has been a growing demand for hexavalent chromium-free films, and various techniques have been proposed.

For example, Patent Document 1 discloses a coated metal material having a urethane-based resin coating mainly composed of a polyurethane resin on a metal material, and describes that it is excellent in corrosion resistance and porosity.

Japanese Patent Application Laid-Open No. 2007-075777

On the other hand, in recent years, along with the enhancement of various kinds of products, the required performance for the metal material to be used is higher.

For example, not only the corrosion resistance which is a characteristic required in Patent Document 1 and the better improvement of the porosity are required but also the adhesion property (film adhesion property) of the coating film disposed on the surface of the metal material and the corrosion resistance after the coating film is formed Corrosion resistance), and chemical resistance to acids and alkalis.

The present inventors conducted surface treatment of a metal material using a urethane resin as described in Patent Document 1 and evaluated various properties of the obtained surface-treated metal material. As a result, it was found that all items were satisfied at a required level There is no such thing, and it is understood that further improvement is necessary.

In view of the above-described circumstances, it is an object of the present invention to provide a metal surface treatment liquid which can obtain a surface-treated metal material excellent in corrosion resistance, porosity, chemical resistance, coating film adhesion and corrosion resistance after coating.

It is another object of the present invention to provide a method for producing a surface-treated metal material using a metal surface treatment liquid and a surface-treated metal material.

As a result of intensive studies on the above problems, the present inventors have found that a desired effect can be obtained by using a metal surface treatment liquid containing a block isocyanate containing a predetermined structure and an organic resin having a predetermined functional group.

More specifically, it has been found that the above object can be achieved by the following constitution.

(1) a block isocyanate (A) having an isocyanate group blocked by a blocking agent and having an isocyanurate structure and a polyalkyleneoxy chain, and

An organic resin (B) having at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a sulfo group and a carboxyl group.

(2) The metal surface treatment liquid according to (1), wherein the block isocyanate (A) has a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2).

(3) The positive resist composition as described in (1) above, which further contains at least one phosphorus containing compound (D) selected from the group consisting of inorganic phosphoric acid, inorganic phosphate, organic phosphoric acid, organic phosphate, organic phosphonic acid and organic phosphonic acid salt. ) Or the metal surface treatment liquid according to (2).

(4) The metal surface treatment liquid according to (3), wherein the phosphorus-containing compound (D) contains at least one member selected from the group consisting of ammonium salts of inorganic phosphoric acid and organic phosphonic acids.

(5) The metal surface treatment liquid according to the above (3) or (4), wherein the mass ratio (A / D) of the block isocyanate (A) and the phosphorus containing compound (D) is 0.1 to 50.

(6) In addition, at least one selected from the group consisting of zirconium, titanium, vanadium, cerium, molybdenum, cobalt, nickel, magnesium, calcium, cerium, zinc, niobium, yttrium, aluminum, tungsten, chromium, The metal surface treatment liquid according to any one of (1) to (5) above, which contains a metal compound (C) containing an element.

(7) The metal surface treatment liquid according to (6), wherein the metal compound (C) contains a zirconium element.

(8) The metal surface treatment liquid according to the above (6) or (7), wherein the metal compound (C) is zirconium ammonium carbonate, zirconium hydrofluoric acid or a salt thereof.

(9) The ratio {a / b} of the effective isocyanate group concentration a (g / l) of the block isocyanate (A) to the concentration b (g / l) of the functional group contained in the organic resin (B) is 0.001 To (30), wherein the metal surface treatment liquid according to any one of (1) to (8) above is used.

(10) The resin composition according to any one of (1) to (9), wherein the concentration of the effective isocyanate group in the block isocyanate (A) is 0.01 to 20 g / l and the concentration of the organic resin (B) is 5 to 100 g / A metal surface treatment liquid according to any one of the preceding claims.

(11) The metal surface treatment liquid according to any one of (1) to (10), wherein the block isocyanate (A) has a weight average molecular weight of 400 to 15000.

(12) The metal surface treatment liquid according to any one of (1) to (11), further containing a silicon compound (E).

(13) The metal surface treatment according to any one of (1) to (12), further comprising an inorganic compound (F) containing at least one element selected from the group consisting of lithium, sodium and potassium liquid.

(14) A process for producing a surface-treated metal material, comprising the step of bringing the metal surface treatment liquid according to any one of (1) to (13) above into contact with the surface of a metal material and then heating and drying to form a film on the metal material .

(15) A surface-treated metal material comprising a metal material and a coating formed by contacting the metal surface treatment liquid according to any one of (1) to (13) above on a metal material and heating and drying.

According to the present invention, it is possible to provide a metal surface treatment liquid capable of obtaining a surface-treated metal material excellent in corrosion resistance, porosity, chemical resistance, coating film adhesion, and corrosion resistance after coating.

According to the present invention, it is also possible to provide a method for producing a surface-treated metal material using a metal surface treatment liquid and a surface-treated metal material.

Hereinafter, the metal surface treatment liquid, the surface-treated metal material and the production method thereof of the present invention will be described in detail. The reason why a desired effect can be obtained by using the metal surface treatment liquid of the present invention is presumed as follows.

The block isocyanate (A) has many polar groups in the molecule such as an isocyanurate structure containing an oxygen atom or a nitrogen atom, or a polyalkyleneoxy chain containing an oxygen atom. These polar groups form a hydrogen bond with the hydroxyl group on the metal material, or form a covalent bond by heating and drying, and as a result, the film is firmly adhered by the metal material. This property has an effect of inhibiting the bond breaking of the metal material and the film due to the increase in pH through the reduction reaction of dissolved oxygen occurring under the film in the corrosive environment. Further, since the adhesion point at the interface between the film and the metal material increases, the film also has an action of peeling off the coating film and suppressing the destruction of the film. Therefore, it effectively works to suppress corrosion such as corrosion resistance.

Most of the isocyanate groups (blocked isocyanate groups) blocked by the blocking agent in the block isocyanate (A) contained in the metal surface treatment liquid are dissociated by heating and drying, but some are considered to remain. These unreacted blocked isocyanate groups can cause alkali hydrolysis in a corrosive environment, while they can act as an alkali catalyst and interact and form new bonds by reaction with coexisting reactants. It acts as a kind of restoration function. Therefore, it serves as a corrosion inhibiting ability to the exposed points of the plating such as the upper part (scratches) and the end faces.

Further, since the coating film formed of the metal surface treatment liquid of the present invention contains a large amount of polar groups, it exhibits excellent adhesion with the coating film disposed on the coating film. In this case, excellent coating film adhesion is exhibited by a hydrogen bond and / or a covalent bond between the functional group contained in the coating film and the functional group contained in the coating film.

Further, the coating formed of the metal surface treatment liquid of the present invention effectively functions also in chemical resistance (solvent resistance and water repellency). These are achieved by the curing reaction of the organic resin (B) coexisting with the block isocyanate (A). This is because the molecular weight of the entire coating is increased by the curing reaction, and the intrusion of the corrosion factor is suppressed by the dense structure formed in the film.

The metal surface treatment liquid contains at least block isocyanate (A) and organic resin (B).

Hereinafter, various components contained in the metal surface treatment liquid will be described in detail, and then the surface-treated metal material and its production method will be described in detail.

≪ Block isocyanate (A) >

The metal surface treatment liquid contains a block isocyanate (A) having an isocyanate group (blocked isocyanate group) blocked by a block agent and also has an isocyanurate structure and a polyalkyleneoxy chain.

The block isocyanate is obtained by reacting an isocyanate group of an isocyanate compound with a blocking agent, and by heating, a protecting group (a block residue) is dissociated to regenerate the isocyanate group. Block isocyanates with low dissociation temperatures regenerate isocyanate groups at relatively low temperatures. In addition, the regenerated isocyanate group undergoes a crosslinking reaction with an organic resin (B) having a specific functional group to be described later to form a bond.

The kind of blocking agent used for blocking (protecting) the isocyanate group is not particularly limited, and a compound having one active hydrogen in the molecule is usually used.

For example, a phenolic blocking agent (e.g., phenol, cresol), a lactam-based blocking agent (e.g., caprolactam, valerolactam), an oxime-based blocking agent (such as formamide oxime, Oxime, methyl ethyl ketoxime), active methylene blockers (e.g., diethyl malonate, dimethyl malonate), alcoholic blocking agents (e.g., methanol, ethanol, ethylene glycol monobutyl ether) (For example, 3,5-dimethylpyrazole), a mercapane-based blocking agent (for example, butyl mercaptan), an acid amide-based blocking agent (for example, acetanilide, acetic acid amide) (For example, imidazole), amine based blocking agents (e.g., diphenylamine, aniline), imine blocking agents (e.g., ethyleneimine), urea based blocking agents , Thiourea), and examples thereof include oxime type block agents, active methylene type block agents, and pyrazole type block agents There may be mentioned preferably.

Among them, a 1,3-dicarbonyl compound or a nitrogen-containing cyclic compound is more preferable.

A block agent having an electron-withdrawing group such as malonate or pyrazole is suitable as the block-like agent and has an effect of lowering the dissociation temperature.

All the isocyanate groups may be blocked by one blocking agent, or two or more blocking agents may be used in combination.

The dissociation temperature of the block isocyanate (A) (the temperature at which the blocked isocyanate group is dissociated) is not particularly limited, but is in the range of 60 to 180 캜 in many cases and is 80 to 120 캜 .

The content of the isocyanate group blocked by the blocking agent in the block isocyanate (A) is not particularly limited, but the content of the effective isocyanate group in the block isocyanate (A) is not particularly limited, and the content of the effective isocyanate group in the block isocyanate (A) is preferably from 0.5 to 10% by mass, more preferably from 1 to 7% by mass, in the total mass of the block isocyanate (A) in terms of at least one of the corrosion resistance after coating (hereinafter simply referred to as " % By mass is more preferable.

The content of the effective isocyanate group means the content of the isocyanate group in the block isocyanate (A) after the block group blocking the isocyanate group is released from the blocked isocyanate group.

The content (concentration) of the effective isocyanate group is specified by the isocyanate equivalent, and is measured in accordance with the method specified in JIS K1603-1. The isocyanate equivalent is g weight number of the block isocyanate (A) containing 1 g equivalent of isocyanate group. The isocyanate equivalent is preferably 150 to 5000, more preferably 300 to 4500, and even more preferably 400 to 4000.

The block isocyanate (A) has an isocyanurate structure (isocyanurate ring structure). The isocyanurate structure is a structure represented by the following formula (X). * Indicates the binding position.

[Chemical Formula 1]

The isocyanurate structure is obtained by cyclization of isocyanate groups of various diisocyanates or triisocyanates.

Examples of the diisocyanate include 1,4-tetramethylene diisocyanate, ethyl (2,6-diisocyanate) hexanoate, 1,6-hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, Aliphatic diisocyanates such as 4- or 2,4,4-trimethylhexamethylene diisocyanate; 1,3- or 1,4-bis (isocyanatomethylcyclohexane), 1,3- or 1,4-diisocyanate cyclohexane, 3-isocyanate-methyl-3,5,5-trimethylcyclohexyl isocyanate, Alicyclic diisocyanates such as hexylmethane-4,4'-diisocyanate, 2,5- or 2,6-diisocyanatomethylnorbornane; m-or p-phenylenediisocyanate, tolylene-2,4- or 2,6-diisocyanate, diphenylmethane-4,4'-diisocyanate, 1,3-bis (2-isocyanate 2-propyl) , Naphthalene-1,5-diisocyanate, diphenyl-4,4'-diisocyanate, 4,4'-diisocyanate 3,3'-dimethyldiphenyl, 3-methyl- And aromatic diisocyanates such as diisocyanate and diphenyl ether-4,4'-diisocyanate.

Examples of the triisocyanate include aliphatic triisocyanates such as 1,3,6-hexamethylene triisocyanate, 1,8-diisocyanate 4-isocyanate methyloctane and 2-isocyanate ethyl (2,6-diisocyanate) ; Cycloaliphatic triisocyanates such as 2,5- or 2,6-diisocyanatomethyl-2-isocyanate propyl norbornane; And aromatic triisocyanates such as triphenylmethane triisocyanate, tris (isocyanate phenyl) thiophosphate, and the like.

The number of isocyanurate structures contained in the block isocyanate (A) is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 4, from the viewpoint of more excellent effects of the present invention.

The block isocyanate (A) has a polyalkyleneoxy chain (for example, a polyethyleneoxy chain or a polypropylene oxy chain).

The polyalkyleneoxy chain is a chain having a structural unit (repeating unit) represented by formula (2).

(2) - (LO) _n -

In the above formula (2), L represents an alkylene group. The number of carbon atoms contained in the alkylene group is not particularly limited, but is preferably from 2 to 10, and more preferably from 2 to 4, because the effect of the present invention is more excellent.

The number of the structural units (repeating units) represented by n is not particularly limited, but is preferably 2 to 1000 (preferably an integer of 2 to 1000), more preferably 5 to 400 , More preferably from 10 to 200.

The molecular weight of the polyalkyleneoxy chain is not particularly limited, but is preferably 100 to 10000, and more preferably 200 to 5000, from the viewpoint of more excellent effects of the present invention.

The content of the polyalkyleneoxy chain in the block isocyanate (A) is not particularly limited, but is preferably 10 to 70% by mass, more preferably 20 to 70% by mass in the total mass of the block isocyanate (A) To 60% by mass is more preferable.

The weight average molecular weight of the block isocyanate (A) is not particularly limited, but is preferably from 400 to 15000, more preferably from 1000 to 7000, more preferably from 300 to 20,000, More preferable.

The weight average molecular weight of the block isocyanate (A) influences the physical properties of the coating film to be formed. Particularly, the weight average molecular weight of the block isocyanate (A) is preferably a high molecular weight (preferably, a weight average molecular weight of 400 to 15000) from the viewpoint of imparting excellent elasticity and strength to the film. The excellent elasticity and hardness are effective not only in imparting mechanical resistance such as porosity, more specifically scratch resistance and abrasion resistance to the coating, but also imparting chemical resistance such as chemical resistance. The film thus obtained effectively acts on the adhesion with the metal material due to the high polarity of the block isocyanate (A) itself.

It is preferable that the block isocyanate (A) is a self-emulsifying (emulsifying) block isocyanate. The self-emulsifying block isocyanate means that the compound itself has affinity for water and can be emulsified and dispersed in water.

When the block isocyanate (A) is self-emulsified in the metal surface treatment liquid described later, the particle diameter of the block isocyanate (A) in the metal surface treatment liquid is preferably from 0.01 to 1.0 Mu m, more preferably 0.05 to 0.5 mu m.

(Preferred embodiment)

Preferred embodiments of the block isocyanate (A) include those having a structural unit represented by the formula (1) and a structural unit represented by the formula (2) in that the effect of the present invention is more excellent. * Indicates the binding position.

(2)

In the formula (1), each X independently represents a divalent hydrocarbon group.

The number of carbon atoms contained in the divalent hydrocarbon group is not particularly limited and is preferably from 1 to 20, more preferably from 2 to 20, and even more preferably from 4 to 12 from the viewpoint of more excellent effects of the present invention.

Examples of the divalent hydrocarbon group include a divalent aliphatic hydrocarbon group, a divalent aromatic hydrocarbon group, or a combination thereof. The bivalent aliphatic hydrocarbon group may be any of linear, branched, and cyclic. Examples of the cyclic aliphatic hydrocarbon group include monocyclic and polycyclic aliphatic hydrocarbon groups. Examples of monocyclic aliphatic hydrocarbon groups include cyclohexanediyl. Examples of polycyclic aliphatic hydrocarbon groups include adamantanediyl group and norbornanediyl group. have.

Among them, preferred examples of the divalent hydrocarbon group include an alkylene group having 1 to 6 carbon atoms, an aliphatic six-membered ring group in which an alkyl group may be substituted, or a xylylenylene group in which an alkyl group may be substituted.

R ₁ represents a residue of a blocking agent. The residues of the blocking agent are intended to be residues from which a hydrogen atom has been removed from a blocking agent capable of reacting with an isocyanate group. The type of block agent is as described above.

Among them, preferred are an alkylamino group having 3 to 8 carbon atoms, a 1,3-dicarbonyl group having 2 to 8 carbon atoms, and a pyrazole group having 2 to 8 carbon atoms.

The number of the structural units represented by the formula (1) in the block isocyanate (A) is not particularly limited, but is the same as the number of the isocyanurate structures described above.

The method of producing the block isocyanate (A) is not particularly limited, and a known method is employed. For example, a polyisocyanate such as a diisocyanate is reacted to prepare a polyisocyanate having an isocyanurate structure, A block agent is added to protect a part of the isocyanate group, and a polyalkyleneoxy compound is further added. The polyalkyleneoxy compound is a compound having a structural unit (repeating unit) represented by the above-mentioned formula (2) and having a group capable of reacting with an isocyanate group such as a hydroxyl group at the terminal (preferably at both terminals) .

When a polyisocyanate having an isocyanurate structure is synthesized, a catalyst (for example, a basic catalyst) may be used if necessary. Examples of the catalyst include hydroxides of tetraalkylammonium, alkylcarboxylic acids such as alkyl metal salts such as tin, zinc and lead, metal alcoholates such as sodium and potassium, and hexamethyldisilazane , A Manish base, a combination of a tertiary amine and an epoxy compound, and a phosphorous compound such as tributylphosphine. These may be used alone or in combination of two or more.

When a basic catalyst is used as the catalyst, neutralization with an acidic compound is preferably performed if necessary. The acidic compound may be used alone or in combination of two or more.

≪ Organic resin (B) >

The metal surface treatment liquid contains an organic resin (B) having at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a sulfo group and a carboxyl group.

The organic resin (B) is preferably an amino group or a carboxyl group because it contains at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a sulfo group and a carboxyl group and is more excellent in the effect of the present invention.

The type of the resin (resin structure) of the organic resin (B) is not particularly limited and may be any of those having the above functional groups. For example, epoxy resin, urethane resin, phenol resin, acrylic resin, acryl- Acryl-styrene copolymer, an alkyd resin, a polyester resin and the like can be used. Among them, water-soluble organic resins that can be dispersed in water medium are preferred.

Specific examples of the organic resin (B) include aromatic epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin and bisphenol S type epoxy resin, polyethylene glycol diglycidyl ether modified products, poly And aliphatic epoxy resins such as propylene glycol diglycidyl ether-modified products. These epoxy resins may be subjected to cationization by introduction of an amino group, anionization by introduction of a carboxyl group, nonionization by introducing a nonionic group such as ethylene oxide, or the like, and the form of hydration may be any form.

It is also preferable that the cationic urethane resin is also cationized, anionized and nonionized by introducing at least one group selected from an amino group, a carboxyl group and an ethylene oxide group into the resin.

As the monomer constituting the urethane resin, sulfur-modified isocyanate and non-sulfur-modified isocyanate can be used. The polyol species may have both an aromatic structure and an aliphatic structure.

In the polyester resin, it is also preferable that the polyester resin is also cationized, anionized, and non-ionized by the introduction of at least one of amino group, carboxyl group and ethylene oxide group. There is no limitation on the monomer constituting the resin.

The phenol resin may be a resin having a main structure such as novolac phenol, resorcinol phenol, or polyvinyl phenol. In the hydrosilation, cationization, anionization, and nonionization can be achieved by introduction of at least one group selected from the group consisting of an amino group, a carboxyl group and an ethylene oxide group.

The acrylic resin can also be cationized, anionized, nonionized, and water-soluble by the introduction of at least one of an amino group, a carboxyl group and an ethylene oxide group. There is no limitation on the monomer constituting the resin.

It is preferable that the organic resin (B) is water-based by a self-emulsification method, but it may be water-based using a cationic surfactant, a nonionic surfactant, an anionic surfactant or a reactive emulsifier. All of these may be used alone or two or more of them may be used in combination.

The various organic resins (B) may be graft-modified. The hydroxyl value of the organic resin (B) preferably ranges from 1 to 1000 mgKOH / g. The amine side of the organic resin (B) is preferably 1 to 800 mgKOH / g. The acid value of the organic resin (B) is preferably 1 to 100 mgKOH / g.

<Other optional components>

The metal surface treatment liquid may contain other components than the block isocyanate (A) and the organic resin (B). Hereinafter, the arbitrary components will be described in detail.

(Metal compound (C))

The metal surface treatment liquid includes at least one kind selected from the group consisting of zirconium, titanium, vanadium, cerium, molybdenum, cobalt, nickel, magnesium, calcium, cerium, zinc, niobium, yttrium, aluminum, tungsten, chromium, The metal compound (C) containing an element may be contained. These compounds are effective for improving the corrosion resistance of the surface-treated metal material and function as dissociation catalysts for blocked isocyanate groups, and furthermore as catalysts for reaction with isocyanate groups, and affect the properties of the coating film in the surface-treated metal material.

Examples of the zirconium compound (compound containing a zirconium element) include inorganic acid salts such as carbonate, chloride, nitrate and sulfate of zirconium, organic acid salts of zirconium oxide and zirconium, zirconium tetraisopropoxide, diisopropoxyzirconium Organic zirconium compounds such as zirconium alkoxide such as diacetyl acetonato and diisopropoxy zirconium ditriethanol aminate, zirconium tetraacetylacetonate and chelate complex containing zirconium atom can be used. Among them, zirconium ammonium carbonate or zirconium hydrofluoric acid or a salt thereof is preferable in that the effect of the present invention is more excellent.

As the titanium compound (compound containing a titanium element), for example, a titanium alkoxide, a chelate complex containing a titanium atom, an inorganic salt of titanium, an organic acid salt and an organic titanium compound are preferable.

The vanadium compound (a compound containing a vanadium element) is preferably a vanadium alkoxide, a chelate complex containing vanadium, an inorganic salt, an organic salt and an oxide of vanadium, and specifically, vanadium oxyacetylacetonate, There may be mentioned a metal oxide such as vanadic acid, sodium metavanadate, potassium metavanadate, ammonium metavanadate, vanadium bisacetylacetonato, vanadyldiacetylacetonato, vanadium pentoxide, vanadium trioxide, vanadium fluoride, vanadium phosphate, vanadium sulfate, oxalic acid Vanadium oxytriisopropoxide, vanadium oxytributoxide, vanadium oxytriisobutoxide, vanadium oxytriethanolaminate, and the like can be given.

As the cerium compound (compound containing a cerium element), for example, a cerium alkoxide, a chelate complex containing cerium, an inorganic salt, an organic salt and an oxide of cerium are preferable.

As the molybdenum compound (compound containing a molybdenum element), for example, a molybdenum alkoxide, a chelate complex containing molybdenum, an inorganic salt, an organic salt and an oxide of molybdenum are preferable.

As the cobalt compound (compound containing a cobalt element), for example, a cobalt alkoxide, a chelate complex containing cobalt, an inorganic salt, an organic salt and an oxide of cobalt are preferable.

As the nickel compound (compound containing nickel element), for example, nickel alkoxide, chelate complex containing nickel, inorganic salt of nickel, organic salt and oxide are preferable.

As the magnesium compound (compound containing magnesium element), for example, a magnesium alkoxide, a chelate complex containing magnesium, an inorganic salt, an organic salt and an oxide of magnesium are preferable.

Examples of the calcium compound (compound containing a calcium element) include calcium carbonate, calcium phosphate, calcium nitrate, calcium sulfate and the like.

Examples of the cerium compound (compound containing a cerium element) include cerium oxide, cerium acetate, cerium (III) nitrate or (IV) nitrate, cerium nitrate, cerium sulfate, cerium chloride and the like.

Examples of the zinc compound (compound containing zinc element) include zinc carbonate, zinc phosphate, zinc nitrate, zinc sulfate, zinc acetate, zinc fluoride, zinc oxide, zinc chloride, zinc tetraethylate, zinc tetrapropylate, Zinc tetrabutylate, zinc tetraacetyl acetonate, zinc monoacetyl acetonate, and zinc lactate.

As the niobium compound (compound containing niobium element), for example, niobium alkoxide, chelate complex containing niobium, inorganic salt of niobium, organic salt and oxide are preferable, and specifically, niobium oxide, Niobium oxide, sodium niobate, magnesium niobium oxide, niobium pentafluorate, niobium pentabutylate, and the like can be given as examples of the niobium compound.

As the yttrium compound (a compound containing a yttrium element), for example, a yttrium alkoxide, a chelate complex containing yttrium, an inorganic salt, an organic salt and an oxide of yttrium are preferable.

As the aluminum compound (a compound containing an aluminum element), for example, an aluminum alkoxide, a chelate complex containing aluminum, an inorganic salt, an organic salt and an oxide of aluminum are preferable.

As the tungsten compound (a compound containing a tungsten element), for example, a vanadium alkoxide, a chelate complex containing tungsten, an inorganic salt, an organic salt and an oxide of tungsten are preferable.

Examples of the chromium compound (a compound containing a chromium element) include chromic acid, bichromic acid, chromium carbonate, chromium chloride, chromium phosphate, chromium nitrate, chromium fluoride, chromium sulfate, chromium acetylacetonate and strontium chromate .

Examples of the barium compound (compound containing a barium element) include barium nitrate, barium carbonate, barium oxide, and the like.

(Phosphorus-containing compound (D))

The metal surface treatment liquid may contain at least one phosphorus-containing compound (D) selected from the group consisting of inorganic phosphoric acid, inorganic phosphate, organic phosphoric acid, organic phosphate, organic phosphonic acid and organic phosphonic acid salt. These compounds are prone to form multivalent ions and can interact (for example, ionic bonds) with the coexisting polar groups. That is, the phosphorus-containing compound (D) acts as a pseudo crosslinking point in the coating film, and as a result, affects the properties of the coating film formed of the metal surface treatment solution. The above-mentioned metal compound (C) is not contained in the phosphorus-containing compound (D).

Examples of the inorganic phosphoric acid and its salt include monophosphoric acids such as phosphoric acid (orthophosphoric acid), phosphorous acid, triphosphoric acid, hypophosphoric acid and hypophosphorous acid, derivatives and salts of monophosphoric acid, metaphosphoric acid, tripolyphosphoric acid, tetraphosphoric acid, Condensed phosphoric acids, derivatives and salts of condensed phosphoric acids, and the like.

Examples of the organic phosphoric acid and its salt include alkylphosphoric acid, phosphoric acid monoester (for example, monododecyl phosphate dihydrogen phosphate, monotridecyl phosphate dihydrogen phosphate and the like) and salt thereof, phosphoric acid diester (for example, Phosphoric acid ditridecyl ether, etc.) and salts thereof. Specific examples of the organic phosphoric acid include, for example, compounds represented by R ₁₀ OP (= O) (OR ₁₁ ) (OR ₁₂ ). R ₁₀ represents an organic group, and R ₁₁ and R ₁₂ each independently represent a hydrogen atom or an organic group. The organic group includes, for example, a hydrocarbon group (for example, an alkyl group, an aryl group, or a combination thereof).

Organic phosphonic acids and salts thereof include, for example, hydroxyethylidene diphosphonic acid, aminotri (methylenephosphonic acid), 1-hydroxyethane-1,1-diphosphonic acid, ethylenediamine-N, , N ', N'-tetra (methylenephosphonic acid), hexamethylenediamine-N, N, N', N'-tetra (methylenephosphonic acid), diethylenetriamine- , N "-penta (methylenephosphonic acid), 2-phosphonobutane-1,2,4-tricarboxylic acid, and salts thereof. Specific examples of the organic phosphonic acid include, for example, compounds represented by R ₁₀ -P (= O) (OR ₁₁ ) (OR ₁₂ ). R ₁₀ represents an organic group, and R ₁₁ and R ₁₂ each independently represent a hydrogen atom or an organic group. The organic group includes, for example, a hydrocarbon group (for example, an alkyl group, an aryl group, or a combination thereof).

The salts such as inorganic phosphates (salts of inorganic phosphoric acid), organic phosphates (salts of organic phosphoric acid) and organic phosphonates (salts of organic phosphonic acids) and the like are not particularly restricted but include, for example, alkali metal salts, Amine salts. Examples of the alkali metal ion constituting the alkali metal salt include lithium ion, sodium ion and potassium ion. Examples of the amine constituting the amine salt include, but are not limited to, alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine and triisopropanolamine; Alkanolalkylamines such as dimethylethanolamine, diethylethanolamine and 2-amino-2-methyl-propanolamine; A monoalkyl primary amine represented by the formula: R ¹ NH ₂ (wherein R ¹ represents a hydrocarbon group having a carbon number of 8 or more and 20 or less); And alkyldiaminopropane represented by the formula: R ² NH (CH ₂ ) ₃ NH ₂ (wherein R ² represents a hydrocarbon group having 5 or more carbon atoms and 17 or less).

Among them, inorganic phosphoric acid, inorganic phosphate, organic phosphonic acid or organic phosphonic acid salt is preferable, and inorganic phosphate (for example, ammonium salt of inorganic phosphoric acid, alkali metal salt of inorganic phosphoric acid, An amine salt of an inorganic phosphoric acid) or an organic phosphonic acid is more preferable, and an ammonium salt of an inorganic phosphoric acid (preferably phosphoric acid) or an organic phosphonic acid is particularly preferable.

(Silicon compound (E))

The metal surface treatment liquid may contain a silicon compound (E).

The silicon compound (E) is preferably at least one of an inorganic silicon compound such as an alkali metal silicate and colloidal silica, or an organic silicon compound such as a silane coupling agent.

Examples of the inorganic silicon compound include lithium silicate, sodium silicate, potassium silicate, and colloidal silica. Examples of the silane coupling agent include vinyl trichlorosilane, vinyltris (2-methoxyethoxysilane), vinyltriethoxysilane, vinyltrimethoxysilane, 3- (methacryloyloxypropyl) tri Methoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyl 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -Aminopropyltriethoxysilane, tetra or trimethoxysilane (tetramethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, etc.) and the like. In addition, a glycidyl group-containing partial condensate obtained by a reaction between tetra or trimethoxysilane and glycidol in a demethanol may be used.

(Inorganic compound (F))

The metal surface treatment liquid may contain an inorganic compound (F) containing at least one element selected from the group consisting of lithium, sodium, and potassium. The inorganic compound (F) does not contain the above-mentioned metal compound (C), the phosphorus-containing compound (D) and the silicon compound (E).

Specific examples of the inorganic compound (F) include hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide, nitrates such as lithium nitrate, fluorides such as sodium fluoride, and sulfates such as sodium sulfate.

(Dicarboxylic acid diester (G))

The dicarboxylic acid diester (G) may be contained in the metal surface treatment liquid. These act as a film-forming auxiliary agent for forming a uniform film.

Specific examples of the dicarboxylic acid diester (G) include succinic acid diesters such as diethoxyethyl succinate and dioctyl succinate, diisopropyl adipate, diisobutyl adipate and diethoxyethyl adipate. Ester, sebacic acid diester such as diethyl sebacate, diisopropyl sebacate, di-octyl sebacate and the like.

(menstruum)

The metal surface treatment liquid may contain water as a solvent. As described later, an organic solvent may be contained.

(Other components)

In order to accelerate the dissociation of the block isocyanate (A) or the reaction between the dissociated isocyanate group of the blocking agent and the functional group in the organic resin (B), an acidic catalyst (for example, hydrochloric acid, Sulfuric acid, nitric acid, phosphoric acid), a basic catalyst (for example, ammonia, trimethylamine, triethylamine), or a metal catalyst.

The metal surface treatment liquids include organic solvents that improve film formability and improve dryness of the film, surfactants that improve wettability, thickeners to adjust the amount of coating, antifoaming agents that suppress foaming, conductive materials to improve weldability, A coloring pigment or the like can be compounded in a range that does not impair the liquid stability of the metal surface treatment liquid or the effect of the present invention.

<Metal surface treatment liquid>

The metal surface treatment liquid contains the various components described above.

Although the content of the block isocyanate (A) in the metal surface treatment liquid is not particularly limited, it is preferable that the effective isocyanate group concentration of the block isocyanate (A) in the metal surface treatment liquid is 0.01 To 20 g / l, more preferably 0.01 to 15 g / l, and still more preferably 0.05 to 10 g / l.

The content of the organic resin (B) in the metal surface treatment liquid is not particularly limited, but it is preferably 5 to 100 g / l, more preferably 10 to 100 g / l in view of better effects of the present invention More preferably 15 to 90 g / l.

The ratio of the mass ratio of the block isocyanate (A) and the organic resin (B) in the metal surface treatment liquid is not particularly limited, but from the viewpoint of the effect of the present invention being more excellent, the concentration of the effective isocyanate group in the block isocyanate (A) (g / l) of the functional group selected from the group consisting of the hydroxyl group, the amino group, the sulfo group and the carboxyl group in the organic resin (B) (the concentration of the effective isocyanate group a (g / / Functional group concentration b) is preferably from 0.001 to 30.0, more preferably from 0.01 to 30, even more preferably from 0.5 to 30, particularly preferably from 1.0 to 15, most preferably from 2.5 to 10 .

The concentration (g / l) of the effective isocyanate group represents the amount (g / g) of the effective isocyanate group in the metal surface treatment liquid (1 l) (G) of the functional group in the molecule (1 liter).

When the metal surface treatment liquid contains the metal compound (C), the content of the metal compound (C) in the metal surface treatment liquid is not particularly limited, but is preferably 0.1 to 50 g / l, and more preferably 0.3 to 10 g / l.

When the phosphorus-containing compound (D) is contained in the metal surface treatment liquid, the content of the phosphorus-containing compound (D) in the metal surface treatment liquid is not particularly limited, but from the standpoint of more excellent effects of the present invention, g / l, more preferably 0.2 to 30 g / l, and still more preferably 0.3 to 10 g / l.

When the metal surface treatment liquid contains the silicon compound (E), the content of the silicon compound (E) in the metal surface treatment liquid is not particularly limited, but it is preferably from 0.1 to 50 g / l, more preferably 0.2 to 30 g / l, and even more preferably 0.3 to 10 g / l.

When the metal surface treatment liquid contains the inorganic compound (F), the content of the inorganic compound (F) in the metal surface treatment liquid is not particularly limited, but it is preferably from 0.1 to 50 g / l, and more preferably 0.5 to 50 g / l.

When the dicarboxylic acid diester (G) is contained in the metal surface treatment liquid, the content of the dicarboxylic acid diester (G) in the metal surface treatment liquid is not particularly limited, but the effect of the present invention is more excellent , Preferably 0.01 to 50 g / l, more preferably 0.05 to 10 g / l.

When the metal surface treatment liquid contains the metal compound (C), the mass ratio (A / C) of the block isocyanate (A) and the metal compound (C) in the metal surface treatment liquid is not particularly limited, Is preferably from 0.1 to 50, more preferably from 0.1 to 25, and even more preferably from 0.1 to 10.

When the phosphorus-containing compound (D) is contained in the metal surface treatment liquid, the mass ratio (A / D) of the block isocyanate (A) and the phosphorus containing compound (D) in the metal surface treatment liquid is not particularly limited, Is preferably 0.1 to 50, more preferably 0.2 to 30, still more preferably 0.3 to 10, and particularly preferably 0.5 to 10, from the viewpoint that the effect of the present invention is better.

When the metal surface treatment liquid contains the silicon compound (E), the mass ratio (A / E) of the block isocyanate (A) to the silicon compound (E) in the metal surface treatment liquid is not particularly limited, Is preferably from 0.1 to 50, more preferably from 0.2 to 30, from the viewpoint of more excellent transparency.

When the metal surface treatment liquid contains the inorganic compound (F), the mass ratio (A / F) of the block isocyanate (A) and the inorganic compound (F) in the metal surface treatment liquid is not particularly limited, Is preferably from 0.1 to 50, and more preferably from 0.5 to 50, from the viewpoint of more excellent properties.

When the dicarboxylic acid diester (G) is contained in the metal surface treatment liquid, the mass ratio (A / G) of the block isocyanate (A) to the dicarboxylic acid diester (G) in the metal surface treatment liquid is not particularly limited However, it is preferably 5 to 100 from the viewpoint that the effect of the present invention is more excellent.

The pH of the metal surface treatment liquid is not particularly limited as long as the effect of the present invention can be attained, but it is preferable that the pH is in the range of 3 to 11 in view of better effects of the present invention.

The solid content concentration of the metal surface treatment liquid is not particularly limited as long as the effect of the present invention can be attained, but it is preferably in the range of 1 to 40% by mass from the viewpoint of better effect of the present invention.

&Lt; Method for producing surface-treated metal material &

The method for producing the surface-treated metal material by using the above-described metal surface treatment liquid is not particularly limited, but usually the above-mentioned metal surface treatment liquid is brought into contact with the surface of the metal material and heated and dried to form a coating film .

Hereinafter, first, the metal material to be processed will be described in detail, and the order of the subsequent steps will be described in detail.

(Metal material)

The kind of the metal material is not particularly limited and may be selected from the group consisting of cold-rolled steel sheets, hot-rolled steel sheets, galvanized steel sheets, aluminum-containing galvanized steel sheets, electrogalvanized steel sheets, galvannealed steel sheets, zinc-nickel-plated steel sheets, alloy steel sheets and coated steel sheets; A metal plate other than a steel plate such as an aluminum plate, a copper plate, a titanium plate, and a magnesium plate may be used. Particularly preferable metal materials are zinc plated steel sheets such as galvanized steel sheets, aluminum-containing galvanized steel sheets, electrogalvanized steel sheets, galvanized steel sheets, zinc-nickel-coated steel sheets, and vapor-deposited galvanized steel sheets.

Prior to the treatment with the metal surface treatment liquid, alkali cleaning, hot water washing, pickling, solvent washing and the like with a degreasing agent are suitably performed in order to remove oil and contamination adhered to the metal material, .

In addition, it is not usually necessary to carry out the undercoating treatment for further improving the corrosion resistance of the metal material and the adhesion of the metal film to the metal material before the treatment with the metal surface treatment liquid. There are no particular limitations on the method of the undercoat treatment, but surface treatment such as application of a metal such as Fe, Co, Ni, Cu, Zn, Mn, Zr, Ti or V, or chemical treatment may be mentioned.

In any of the treatments described above, it is preferable to wash the surface of the metal material so that the treatment liquid does not remain on the surface of the metal material.

(order)

The method of contacting the metal surface treatment liquid to the metal material is not particularly limited, and examples thereof include a roll coating method, a dipping method, a spraying method, and a bar coating method.

The temperature of the treatment liquid at the time of contact is not particularly limited, but is preferably 10 to 60 占 폚, more preferably 15 to 40 占 폚.

Further, after bringing the metal material into contact with the metal surface treatment liquid, the metal material is subjected to heat drying treatment. The heating and drying method is not particularly limited, and examples thereof include a dryer, a hot air furnace, a high frequency induction heating furnace, and an infrared furnace. In order to enhance the coating effect by accelerating curing and crosslinking of the block isocyanate (A) and the organic resin (B), it is preferable to heat and dry by a hot air furnace, an induction heating furnace, an electric furnace or the like. The heating and drying temperature is not particularly limited, but the temperature of the metal material at the time of drying is preferably 50 to 250 ° C, more preferably 70 to 220 ° C.

By carrying out the above treatment, a surface-treated metal material having a metal material and a coating disposed on the surface thereof is obtained.

The coating amount (coating weight) of the coating film is not particularly limited and is preferably 0.05 to 10.0 g / m 2, more preferably 0.1 to 8.0 g / m 2, more preferably 0.1 to 5.0 g / m 2 Is more preferable.

The basic physical properties of the coating are conventionally measured by a DMA (dynamic viscoelastic device) and are obtained as storage elastic modulus and loss elastic modulus. The storage modulus represents an elastic component that reacts uniformly to the stress imparted, such as a spring, while the loss modulus represents a viscous component that reacts slowly to a given stress. In short, the storage elastic modulus is a component directly influencing the strength of the coating film, and the coating film having a high storage elastic modulus can be said to be a hard coating film. The loss elastic modulus is a component showing flexibility, and the coating having a high loss elastic modulus is a more flexible film. The temperature at which the loss elastic modulus attains the maximum value is expressed by the maximum loss tangent tan?, And when the temperature is too high, the coating is friable, while if too low, the coating becomes soft.

The storage elastic modulus at room temperature of the coating film is preferably from 0.1 to 5 mm, more preferably from 0.2 to 4 mm, and further preferably from 0.5 to 2 mm, since the effect of the present invention is better.

The temperature (Tan? Max) showing the maximum loss tangent tan? Of the film is preferably 25 to 80 占 폚, more preferably 30 to 75 占 폚, and most preferably 30 to 70 占 폚 Is more preferable.

A coating film may be formed on the surface (coating film) of the above-mentioned surface-treated metal material, if necessary. The resulting coating film is excellent in adhesion and corrosion resistance.

The paint may be a water-based paint or a solvent-based paint. The curing type is not particularly limited and may be thermosetting or electron beam curing. In addition to the general coating material, a film coat such as a laminate may be applied to the surface of the surface-treated metal material of the present invention (coating film).

The above-mentioned surface-treated metal material can be used for various applications, and examples thereof include members for household appliances and building materials.

Example

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited to these Examples.

<1. Synthesis of block isocyanate (A) >

1.1 Preparation of polyisocyanate

300 g of each isocyanate shown in the column of &quot; isocyanate species &quot; in Table 1 was added to a reactor (1 liter separable flask) equipped with a stirrer, and 0.1 g of trimethylbenzylammonium hydroxide as a catalyst . After 4 hours, when the conversion of the reaction solution reached 38%, 0.2 g of phosphoric acid was added to terminate the reaction.

2.2 Preparation of block isocyanate

Hereinafter, a method for preparing a block isocyanate will be described. As the &quot; polyisocyanate &quot; used in each of the synthesis examples, the polyisocyanate prepared in the above procedure was used by using the isocyanate described in the &quot; isocyanate species &quot; column of each synthesis example shown in Table 1.

However, in Synthesis Example A10 to be described later, 1,6-hexamethylene diisocyanate, which is a monomer, was used.

In addition, the block isocyanate synthesized in each Synthesis Example is a so-called self-emulsifying block isocyanate.

(Synthesis Example A1)

Polyisocyanate (100 g), diethyl malonate (63.5 g) and sodium methoxide (1.0 g) were charged to the reactor and heated at 65-70 ° C. Then, polyethylene glycol (188.4 g) (the number of repeating units (n): 22) was added to the reaction solution, and the temperature of the reaction solution was kept at 70 占 폚 and held for 5 hours. Then, while stirring the reaction solution, water (430 g) was added to the reaction solution to prepare a block isocyanate emulsion.

(Synthesis Examples A2 and A6)

Polyisocyanate (100 g), 3,5-dimethylpyrazole (28.8 g) and sodium methoxide (1.0 g) were charged to the reactor and heated at 65-70 ° C. Then, polyethylene glycol (188.4 g) was added to the reaction solution, and the reaction solution temperature was maintained at 70 占 폚 and held for 5 hours. Then, while stirring the reaction solution, water (430 g) was added to the reaction solution to prepare a block isocyanate emulsion.

Further, at the time of manufacturing each of A2 and A6, the kind of the polyethylene glycol was changed so that the weight average molecular weight was obtained as shown in Table 1. Specifically, polyethylene glycol (number of repeating units (n): 22) was used for synthesis of A2, and polyethylene glycol (number of repeating units (n): 180) was used for synthesis of A6.

(Synthesis Example A3)

A block isocyanate emulsion was prepared in the same manner as in Synthesis Example A2 except that polyethylene glycol was changed to polypropylene glycol (number of repeating units (n): 17).

(Synthesis Example 4)

Polyisocyanate (100 g), 3,5-dimethylpyrazole (31.6 g) and sodium methoxide (1.0 g) were charged to the reactor and heated at 65-70 ° C. Then, polyethylene glycol (640 g) (the number of repeating units (n): 91) was added to the reaction solution, the temperature of the reaction solution was raised to 70 캜 and held for 5 hours. Thereafter, while stirring the reaction solution, water (1100 g) was added to the reaction solution to prepare a block isocyanate emulsion.

(Synthesis Example A5)

Polyisocyanate (100 g), 3,5-dimethylpyrazole (26.2 g) and sodium methoxide (1.0 g) were charged to the reactor and heated at 65-70 ° C. Then, polyethylene glycol (136.6 g) (the number of repeating units (n): 68) was added to the reaction solution, and the temperature of the reaction solution was kept at 70 占 폚 and held for 5 hours. Thereafter, while stirring the reaction solution, water (350 g) was added to the reaction solution to prepare a block isocyanate emulsion.

(Synthesis Examples A7 and A8)

A block isocyanate emulsion was prepared in the same manner as in Synthesis Example A2 except that 3,5-dimethylpyrazole was changed to methyl ethyl ketoxime or ethylene glycol monobutyl ether.

(Synthesis Example A9)

Polyisocyanate (100 g), 3,5-dimethylpyrazole (26.2 g) and sodium methoxide (1.0 g) were charged to the reactor and heated at 65-70 ° C. Then, polyethylene glycol (3571 g) (the number of repeating units (n): 409) was added to the reaction solution, and the temperature of the reaction solution was kept at 70 占 폚 and held for 5 hours. Thereafter, water (5600 g) was added to the reaction solution while stirring the reaction solution to prepare a block isocyanate emulsion.

(Synthesis Example A10)

Isocyanate (100 g), diethyl malonate (190.5 g) and sodium methoxide (1.0 g) were charged into the reactor and the reaction was heated at 65-70 캜. Then, while stirring the reaction solution, water (530 g) was added to the reaction solution to prepare a block isocyanate emulsion.

(Synthesis Example A11)

Polyisocyanate (100 g), diethyl malonate (95.2 g) and sodium methoxide (1.0 g) were charged to the reactor and the reaction was heated at 65-70 ° C. Thereafter, while stirring the reaction solution, water (290 g) was added to the reaction solution to prepare a block isocyanate emulsion.

(Synthesis Example A12)

Polyisocyanate (100 g), dimethyl pyrazole (75.7 g) and sodium methoxide (1.0 g) were charged into the reactor and the reaction was heated at 65-70 ° C. Thereafter, water (260 g) was added to the reaction solution while stirring the reaction solution to prepare a block isocyanate emulsion.

The weight average molecular weight of the obtained block isocyanate was determined by GPC (gel permeation chromatography), and the weight average molecular weight in terms of polyethylene glycol was determined as the relative molecular weight distribution of the block isocyanate. The measurement conditions of GPC are as follows.

Measuring apparatus: SC-8010 system manufactured by Tosoh Corporation

Column: Shodex Ohpak SB-G + Ohpak SB-806MHQ × 2

Solution: DMF / 0.06 M LiBr / 0.04 MH ₃ PO ₃

Temperature: Column constant temperature bath 40 ℃

Flow rate: 0.05 ml / min

Concentration: 0.1 wt / Vol%

Injection amount: 50 μl

Solubility: completely soluble

Pretreatment: 0.45 탆 filter

Detector: differential refractometer

The isocyanurate structure (the structural unit represented by the formula (1)) and the polyalkyleneoxy chain (the structural unit represented by the formula (2)) were contained in the A1 to A9 synthesized above.

A10 did not contain an isocyanurate structure and a polyalkyleneoxy chain, and A11 and A12 contained no polyalkyleneoxy chain.

In the following Table 1, in the &quot; polymerization type &quot; column, &quot; trimer &quot; is intended to include an isocyanurate structure, and &quot; monomer &quot; is intended to mean isocyanate in a monomer state.

The &quot; dissociation temperature &quot; represents the dissociation temperature of the blocked isocyanate group.

The "particle size" indicates the particle diameter of the block isocyanate in each block isocyanate emulsion.

The "alkyleneoxy group" represents the number of alkyleneoxy units (n in formula (2)).

&Quot; Effective NCO% &quot; is intended to mean the content (% by mass) of the effective isocyanate group in each block isocyanate.

Each symbol in the above table indicates the following.

HDI: 1,6-hexamethylene diisocyanate, IPDI: 3-isocyanate-methyl 3,5,5-trimethylcyclohexyl isocyanate, TMXDI: 1,3-bis (2-isocyanate 2-propyl) benzene, TDI: Ethylene glycol monobutyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether, ether

<2. Preparation of metal surface treatment liquid>

(A), the organic resin (B), the metal compound (C), the phosphorus-containing compound (D), the silicon compound (B), and the silicon isocyanate (A) in the combinations and ratios shown in Tables 2 to 4 using the block isocyanate The metal surface treatment liquid used in the examples and the comparative examples was prepared by mixing the compound (E), the inorganic compound (F) and the dicarboxylic acid diester (G) in this order and adjusting the concentration by deionized water.

B1: Epoxy resin (Water Sol EFD-5560, DIC) (type of functional group containing: hydroxyl group)

B2: urethane resin (Hydran COR-70, DIC) (types of functional groups contained: amino group)

B3: Acrylic resin (Water sol S-701, DIC) (type of functional group containing: carboxyl group)

C1: Zirconium carbonate ammonium

C2: Zirconium hydrofluoric acid

D1: Ammonium phosphate

D2: Hydroxyethylidene diphosphonic acid

D3: Triethanolamine phosphate

E1: 3-glycidoxypropyltrimethoxysilane

F1: lithium hydroxide

G1: diisobutyl adipate

<3. Surface treatment>

Hereinafter, the surface treatment method, the evaluation method, and the evaluation result will be described in the order of the hot-dip galvanized steel sheet, the electro-galvanized steel sheet or the cold-rolled steel sheet. In addition, the evaluation results are summarized in Tables 2 to 4.

[One. Material]

GI: Hot-dip galvanized steel sheet (plate thickness: 0.8 mm, apparent weight: 60 g / m 2)

EG: Electro galvanized steel sheet (plate thickness: 0.8 mm, apparent weight: 20 g / m 2)

CRS: Cold rolled steel plate (plate thickness: 0.8 mm)

[2. Surface treatment method]

(1) degreasing

Each material was degreased with an alkali degreasing agent Fine Cleaner E6406 (20 g / l bath, 60 캜, 10 seconds spray, spray pressure 0.5 kg / cm 2) manufactured by Nippon Pharmaceutical Co., Respectively.

(2) Application and drying

Each of the degreased materials obtained in (1) above was coated with a metal surface treatment liquid such that the coating weight was 1 g / m 2, and dried at 150 ° C (PMT) to prepare samples for each treatment plate.

[3. Evaluation items]

(1) Corrosion resistance

(1-1) About GI and EG

The GI and EG treated plate samples produced in the examples and comparative examples were subjected to the following corrosion resistance tests on the planar part and the cross section. The evaluation method is as follows.

(Plane portion)

Based on the salt spray test method JIS-Z-2371, the white rust occurrence area ratio (the ratio of the white rust occurrence area to the total area of the flat part) after 240 hours of spraying with salt water was determined and evaluated according to the following criteria. As for the corrosion resistance on the flat surface, it was accepted as ◎ to □.

[Evaluation standard]

◎: Less than 10% of white rust area

○: White rust occurrence area ratio 10% or more and less than 20%

□: Area of occurrence of white rust 20% or more and less than 30%

△: area ratio of white rust is 30% or more and less than 60%

X: Ratio of white rust area 60% or more

(Section)

The salt spray test prescribed in JIS-Z2371 was conducted for 48 hours, and the rust width from the cross section was visually evaluated and evaluated according to the following criteria. As for the corrosion resistance of the cross section, ⊚ to 합 were accepted.

[Evaluation standard]

◎: less than 5 mm rust width

○: Rust width 5 mm or more and less than 7 mm

□: Rust width 7 ㎜ or more and less than 8.5 ㎜

△: Rust width 8.5 ㎜ or more and less than 10 ㎜

×: Rust width of 10 mm or more

(1-2) About CRS

The CRS treated plate samples produced in the examples and comparative examples were subjected to the following corrosion resistance test. The evaluation method is as follows.

(Plane portion)

Based on the salt spray test method JIS-Z-2371, the white rust occurrence area ratio (the ratio of the white rust occurrence area to the total area of the plane portion) after 72 hours of salt water spraying was determined and evaluated according to the following criteria. For the corrosion resistance, ◎ ~ □ were accepted.

[Evaluation standard]

◎: Less than 10% of white rust area

○: White rust occurrence area ratio 10% or more and less than 20%

□: Area of occurrence of white rust 20% or more and less than 30%

△: area ratio of white rust is 30% or more and less than 60%

X: Ratio of white rust area 60% or more

(2) I was siege

Both sides of the treated plate sample were subjected to a drawing process at a rate of 100 mm / min while applying a load of 10 kN using a flat indenter having a size of 20 mm x 50 mm, and the appearance of the test piece (treated plate sample) was evaluated visually , The ratio of the discoloration area (the ratio of the discoloration area to the area of the drawn portion) was determined and evaluated according to the following criteria. I passed ◎ ~ □ for siege.

[Evaluation standard]

◎: No change at all

○: The ratio of discoloration area exceeds 0% to 10% or less

□: Percentage of discoloration area exceeds 10% and below 30%

?: The ratio of the discoloration area exceeds 30% to 50%

X: Percentage of discoloration area exceeds 50%

(3) Chemical resistance

(3-1) Alkalinity

The degreasing agent used in the degreasing was adjusted to 65 캜 and sprayed on the treated plate for 2 minutes. Thereafter, the appearance of the test piece (treated plate sample) was visually observed and evaluated according to the following criteria. As for the alkali resistance, ⊚ to 합 were regarded as acceptable.

[Evaluation standard]

◎: No change at all

○: The ratio of discoloration area exceeds 0% to 10% or less

□: Percentage of discoloration area exceeds 10% and below 30%

?: The ratio of the discoloration area exceeds 30% to 50%

X: Percentage of discoloration area exceeds 50%

(3-2) Acid resistance

The treated plate samples were immersed in 1% aqueous sulfuric acid solution for 5 hours. Thereafter, the appearance of the test piece (treated plate sample) was visually observed and evaluated according to the following criteria. For acid resistance, ◎ to □ were accepted.

[Evaluation standard]

◎: No change at all

○: The ratio of discoloration area exceeds 0% to 10% or less

□: Percentage of discoloration area exceeds 10% and below 30%

?: The ratio of the discoloration area exceeds 30% to 50%

X: Percentage of discoloration area exceeds 50%

(4) Coating film adhesion

Each treated plate sample was painted using a melamine alkyd paint (DERICON # 700, manufactured by Dainippon Paint Co., Ltd.). The coating was carried out by applying a bar coat, and after coating, baking was carried out at 140 ° C for 20 minutes to form a coating film (surface-treated product) having a thickness of 25 μm after drying.

Two sheets of the same thickness as the original plate were used, and a coating film (surface treated product) was sandwiched therebetween and subjected to a 180 degree bending process. The tape was peeled off from the bent portion and evaluated according to the following criteria. As for the film adhesion, ⊚ to 합 passed.

[Evaluation standard]

◎: No peeling

○: peeled area exceeding 0% and not more than 10%

□: Peel area is over 10% and below 30%

?: Peeling area exceeding 30% and not more than 50%

X: Peel area exceeded 50%

(5) Corrosion resistance after painting

(5-1) About GI and EG

The coating film obtained in the above (4) was subjected to crosscutting with an NT cutter (Type A300, manufactured by NIPPON KOGYO CO., LTD.) And subjected to a salt spray test prescribed in JIS-Z2371 for 480 hours. And evaluated according to the following criteria. The corrosion resistance after coating was rated as ◎ to □.

[Evaluation standard]

◎: less than 5 mm rust width

○: Rust width 5 mm or more and less than 7 mm

□: Rust width 7 ㎜ or more and less than 8.5 ㎜

△: Rust width 8.5 ㎜ or more and less than 10 ㎜

×: Rust width of 10 mm or more

(5-2) About CSR

The coated film obtained in the above (4) was subjected to crosscutting with an NT cutter (Type A300 manufactured by NIPPON KOGYO CO., LTD.) And subjected to a salt water spray test prescribed in JIS-Z2371 for 120 hours to visually evaluate the rust width from the cross- And evaluated according to the following criteria. The corrosion resistance after coating was rated as ◎ to □.

[Evaluation standard]

◎: Less than 3 mm of rust width

○: Rust width 3 mm or more and less than 6 mm

□: Rust width 6 ㎜ or more and less than 7.5 ㎜

?: Rust width not less than 7.5 mm and less than 10 mm

×: Rust width of 10 mm or more

Table 2 shows the results of using hot dip galvanized steel sheets (GI) as a specimen, Table 3 shows the results of using an electrogalvanized steel sheet (EG) as a specimen, and Table 4 shows the results of using cold rolled steel sheets (CRS) Indicates the used result.

The concentration of the block isocyanate (A) in Tables 2 to 4 indicates the concentration (g / l) of the effective isocyanate group contained in the block isocyanate (A) in the metal surface treatment liquid. The concentration of the organic resin (B) in Tables 2 to 4 indicates the concentration (g / l) of the organic resin (B) in the metal surface treatment liquid.

In the Tables 2 to 4, "a / b" represents the concentration (g / ℓ) of the effective isocyanate group contained in the block isocyanate (A) in the metal surface treatment liquid, (A / b) of the concentration b (g / l) of the hydroxyl group (at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a sulfo group and a carboxyl group)

"A / C" in Tables 2 to 4 represents the ratio of the mass of the block isocyanate (A) to the mass of the metal compound (C), and "A / D" represents the mass of the block isocyanate (A) A is the ratio of the mass of the block isocyanate (A) to the mass of the silicon compound (E), and A / F is the mass of the block isocyanate (A) F), and "A / G" represents the ratio of the mass of the block isocyanate (A) to the mass of the dicarboxylic acid diester (G).

&Quot; Storage elastic modulus &quot; and &quot; Tanδmax &quot; in Table 2 indicate the storage elastic modulus and the temperature showing the maximum loss tangent Tan delta at room temperature of the coating films produced in the respective Examples and Comparative Examples. The &quot; storage elastic modulus &quot; and &quot; Tanδmax &quot; were measured by RSA-G2 (TA instrument).

As can be seen from Tables 2 to 4, it was confirmed that the surface-treated metal material obtained by applying the metal surface treatment liquid of the present invention exhibited various excellent properties.

Among them, the comparison of Examples A1 to A14 shows that the ratio (a / b) of the concentration (g / l) of the effective isocyanate group / the concentration (g / l) of the functional group in the organic resin (B) , It is confirmed that a more excellent effect can be obtained in the case of 0.5 to 30, more preferably 1.0 to 15.

From the comparison of Examples A15 to A19, it was confirmed that more excellent effects were obtained when the dissociation temperature of the block isocyanate was 120 占 폚 or lower.

From the comparison between Example A20 and Example A17, it was confirmed that a more excellent effect was obtained in the range of the weight average molecular weight of the block isocyanate of 400 to 15,000.

(A / D) of the block isocyanate (A) and the phosphorus-containing compound (D) is 0.5 to 50 (preferably 0.2 to 30, more preferably 0.3 to 10) , It was confirmed that a more excellent effect was obtained.

From the comparison between Examples A24 and A28 and A30, it was confirmed that a superior effect was obtained when the phosphorus-containing compound (D) was an ammonium salt of an inorganic phosphoric acid or an organic phosphonic acid.

On the other hand, it was confirmed that when the metal surface treatment solution described in Comparative Example which did not satisfy the predetermined requirements was used, a desired effect could not be obtained.

Claims (15)

A block isocyanate (A) having an isocyanate group blocked by a blocking agent and having an isocyanurate structure and a polyalkyleneoxy chain,
An organic resin (B) having at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a sulfo group and a carboxyl group. The method according to claim 1,
Wherein the block isocyanate (A) has a structural unit represented by formula (1) and a structural unit represented by formula (2).
[Chemical Formula 1]

(In the formula (1), each X independently represents a divalent hydrocarbon group, R ₁ represents a residue of the blocking agent, and * represents a bonding position.)
(2) - (LO) _n -
(In the formula (2), L represents an alkylene group, and n represents 2 to 1000.) 3. The method according to claim 1 or 2,
(D) at least one phosphorus-containing compound selected from the group consisting of inorganic phosphoric acid, inorganic phosphate, organic phosphoric acid, organic phosphate, organic phosphonic acid, and organic phosphonic acid salt. The method of claim 3,
Wherein the phosphorus-containing compound (D) contains at least one member selected from the group consisting of an ammonium salt of inorganic phosphoric acid and an organic phosphonic acid. The method according to claim 3 or 4,
Wherein the mass ratio (A / D) of the block isocyanate (A) and the phosphorus-containing compound (D) is 0.1 to 50. 6. The method according to any one of claims 1 to 5,
In addition, it is preferable to contain at least one element selected from the group consisting of zirconium, titanium, vanadium, cerium, molybdenum, cobalt, nickel, magnesium, calcium, cerium, zinc, niobium, yttrium, aluminum, tungsten, chromium, And the metal compound (C) is added to the metal surface treatment liquid. The method according to claim 6,
Wherein the metal compound (C) contains a zirconium element. 8. The method according to claim 6 or 7,
Wherein the metal compound (C) is zirconium ammonium carbonate, zirconium hydrofluoric acid or a salt thereof. 9. The method according to any one of claims 1 to 8,
The ratio {a / b} of the effective isocyanate group concentration a (g / l) of the block isocyanate (A) to the concentration b (g / l) of the functional group contained in the organic resin (B) is 0.001 To 30.0. 10. The method according to any one of claims 1 to 9,
Wherein the concentration of the effective isocyanate group contained in the block isocyanate (A) is 0.01 to 20 g / l and the concentration of the organic resin (B) is 5 to 100 g / l. 11. The method according to any one of claims 1 to 10,
Wherein the block isocyanate (A) has a weight average molecular weight of 400 to 15000. 12. The method according to any one of claims 1 to 11,
Further, a metal surface treatment liquid containing a silicon compound (E). 13. The method according to any one of claims 1 to 12,
Further, a metal surface treatment liquid containing an inorganic compound (F) containing at least one element selected from the group consisting of lithium, sodium and potassium. A process for producing a surface-treated metal material, comprising the step of bringing the metal surface treatment liquid according to any one of claims 1 to 13 into contact with a surface of a metal material, followed by heating and drying to form a film on the metal material. A surface treated metal material comprising a metal material and a coating formed by contacting the metal surface treatment liquid according to any one of claims 1 to 13 and heating and drying the metal material.