JP2018080243A - One-liquid type aqueous resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a urethane coating having excellent corrosion resistance, chemical resistance, and alkali resistance, and also excellent storage stability with time.SOLUTION: A one-liquid type aqueous resin composition contains a polyurethane resin, (e) a metal cross-linker, and water, wherein the polyurethane resin is obtained by the reaction between (d) a chain extender and a urethane prepolymer, which is a product resulting from the reaction between (a) polycarbonate diol, (b) polyisocyanate, and (c) an anionic-group introduction agent.SELECTED DRAWING: None

Description

  The present invention relates to a one-component aqueous resin composition. More specifically, a one-part aqueous resin composition for coating excellent in chemical resistance and alkali resistance using an aqueous polyurethane resin composition that has good miscibility with a metal crosslinking agent, a method for producing the same, and the resin composition The present invention relates to a paint using an object.

  Concrete used for construction and civil engineering structures is an excellent material having an effect of inhibiting corrosion of internal rebar due to its inherent alkalinity, but has a problem of aging over time. One of the causes is that the calcium hydroxide in the concrete is neutralized by the absorption of salt water or carbon dioxide that has cracked due to high-temperature drying conditions, and the pH in the concrete is lowered. Corrosion can reduce the durability of the structure. In order to prevent cracking, a sufficient wet curing period for the hardened concrete to sufficiently harden is indispensable, but it is rather rare that a sufficient wet curing period is secured under normal construction conditions. Therefore, as a method for suppressing the deterioration of the structure, there is an application of a protective material for concrete to make it difficult for salt water or carbon dioxide to touch the reinforcing bars.

  Patent Document 1 proposes a concrete coating material using an acrylic polymer dispersion having a glass transition temperature of −50 to −20 ° C. This method can protect concrete from an external environment such as a certain amount of water and salt water, but the coating film has poor flexibility and also has a problem regarding durability such as solvent resistance. .

  On the other hand, urethane resin is a material widely used in paints, adhesives, binders, coating agents, etc., because it gives a coating film or molded article having wear resistance, adhesion, non-tackiness, rubber elasticity, etc. is there. In recent years, from the viewpoint of safety against environmental pollution, occupational health, etc., many water-based polyurethane compositions in which urethane resins are water-based have been reported, but water-based polyurethane compositions are solvent-based or solvent-free. Compared with this, there is a problem that physical properties such as water resistance, heat resistance and tensile properties are inferior.

  In patent document 2, the metal surface treating agent which used a rust preventive agent, colloidal silica, and basic alkali silicate together with the water-based polyurethane resin is provided. This metal surface treatment agent is a suitable material for protecting metal plates such as galvanized steel sheets by using a water-based polyurethane resin based on polyester polyol, but it should be thickened. However, it was not satisfactory when protecting concrete. In addition, even if it is attempted to increase the strength of the coating film by adding a crosslinking agent to the aqueous polyurethane resin used in this method, the miscibility of the crosslinking agent and the aqueous polyurethane resin is poor and a practical level is obtained. I couldn't.

JP 2001-342048 A International Publication No. 2011/122119

  The problem to be solved by the present invention is to provide a water-based resin composition that takes into consideration the environment and the human body while maintaining the flexibility to follow cracks in concrete and having good durability of the coating film. It is in.

  Therefore, the present inventors diligently studied and used a water-based polyurethane resin composition using a polycarbonate diol as a polyurethane resin base material and a metal crosslinking agent in combination, good miscibility, and further, the flexibility of the coating film. The inventors have found an aqueous resin composition having a good balance of durability and have reached the present invention. That is, the present invention is as follows.

  (1): (a) polycarbonate diol, (b) polyisocyanate, (c) polyurethane resin obtained by reaction of urethane prepolymer which is a reaction product of an anionic group introducing agent and (d) chain extender, and (E) One-pack type aqueous resin composition containing a metal crosslinking agent and water.

  (2): One or more selected from (a) polycarbonate diol selected from 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and 2-methyl-1,3-propanediol A one-component aqueous resin composition according to (1), which is a polycarbonate diol based on the diol of (1), wherein (e) the metal crosslinking agent is one or more compounds selected from zirconium-based compounds.

  (3): (b) The polyisocyanate is one or more compounds selected from tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and 4,4-dicyclohexylmethane diisocyanate, according to (1) or (2) One-pack type aqueous resin composition.

  (4): (c) The one-component aqueous resin composition according to any one of (1) to (3), wherein the anionic group introducing agent is one or more compounds selected from polyols containing a carboxyl group. object.

  (5): (d) The one-part aqueous system according to any one of (1) to (4), wherein the chain extender is at least one compound selected from diamines, hydrazides, hydrated hydrazine, and water. Resin composition.

  (6): The content of (e) the metal crosslinking agent is 0.1 to 15% by mass with respect to the total amount of the polyurethane resin and (e) the metal crosslinking agent, and any one of (1) to (5) One-pack type aqueous resin composition.

  (7): The one-component water-based resin composition according to any one of (1) to (6), in which no change in appearance by visual observation is observed after storage at 50 ° C. for 2 weeks.

  (8) The one-component aqueous resin composition according to any one of (1) to (7), which is for coating.

  (9): The manufacturing method of the one-pack type aqueous resin composition in any one of Claims 1-8 including the following processes 1-4. (Step 1) (a) Polycarbonate diol, (b) polyisocyanate, and (c) a step of producing a urethane prepolymer by reacting with an anionic group introducing agent, (Step 2) dispersing the urethane prepolymer in water. Step (Step 3) A polyurethane resin is synthesized by reacting the urethane prepolymer in the aqueous dispersion with (d) a chain extender, and an aqueous polyurethane resin composition containing the polyurethane resin at a concentration of 10 to 70% by mass is prepared. A step of manufacturing, (step 4) a step of mixing the water-based polyurethane resin composition with (e) a metal crosslinking agent to manufacture a one-pack type water-based resin composition.

  (10): A paint comprising the one-component aqueous resin composition of any one of (1) to (8).

  The effect of this invention is providing the water-based resin composition suitable for protection of concrete by mixing the water-based polyurethane resin composition using polycarbonate diol, and a metal crosslinking agent by a suitable mixing | blending. High-rise buildings, roads, dams, and other structures using concrete coated with a paint using the resin composition maintain durability against water, salt water, and the like, and suppress deterioration over time.

  The one-component aqueous resin composition of the present invention contains a polyurethane resin, a metal crosslinking agent, and water as essential components. The polyurethane resin is obtained by reacting a urethane prepolymer obtained by reacting (a) polycarbonate diol, (b) polyisocyanate, and (c) an anionic group introducing agent with (d) a chain extender. Resin. Since the structure of such a polyurethane resin does not have a repeating unit that is complex and regularly bonded or has a specific overall structure, such a polyurethane resin cannot be defined by a specific name, general formula, or specific repeating unit. Therefore, in the present invention, such a polyurethane resin must be specified by its production method. Hereinafter, the component which comprises the one-pack type aqueous resin composition of this invention, and its manufacturing method are demonstrated.

[(A) Polycarbonate diol]
Polyol is generally used as a raw material for a polyurethane resin, and has a function of improving the weather resistance and strength of the polyurethane resin. In the present invention, as a polyol that is a raw material of a polyurethane resin, a specific polyol that gives a polyurethane resin having good mixing stability without gelation even after a long time after mixing with a metal crosslinking agent, that is, (a) polycarbonate diol Use.

  The (a) polycarbonate diol of the present invention is a polyol having a polycarbonate bond in the molecule. As such (a) polycarbonate diol, what is obtained by making carbonate and / or phosgene react with the polyol mentioned later, for example can be used. Examples of the carbonate ester include dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, diphenyl carbonate, dinaphthyl carbonate, and phenyl naphthyl carbonate.

  Examples of the polyol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, , 3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,5-hexanediol, 1,6-hexanediol, 2,5-hexanediol, 1, 7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 2-methyl-1,3-propanediol , Neopentyl glycol, 2-butyl-2- Til-1,3-propanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, 1,4-cyclohexanedimethanol, Dihydroxy compounds having a molecular weight of 500 or less, such as hydroquinone, resorcin, bisphenol A, bisphenol F, 4,4′-biphenol, polyether polyols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyhexamethylene adipate, Polyester polyols such as polyhexamethylene succinate and polycaprolactone can be used.

  Among these polyols, a dihydroxy compound having a molecular weight of 500 or less is preferable from the viewpoint of availability, and 1,3-propanediol and 1,4-butanediol have good weather resistance and can be obtained at low cost. 1,6-hexanediol and 2-methyl-1,3-propanediol are more preferable.

  The number average molecular weight of the (a) polycarbonate diol used in the present invention is preferably 500 to 5000 from the viewpoint of workability such as strength when a urethane resin is formed into a film and viscosity when producing a urethane prepolymer. Yes, more preferably 1000 to 3000. (A) When the number average molecular weight of the polycarbonate diol is smaller than 500, the viscosity of the urethane prepolymer is remarkably increased and water dispersibility tends to be difficult. (A) When the polycarbonate diol is larger than 5000, the physical properties of the coating film of the obtained one-component aqueous resin composition tend to be remarkably lowered.

  On the other hand, polyurethane resins using polyester polyols or polyether polyols as raw materials, which are generally used in the production of polyurethane resins, have good durability but are poorly miscible with metal cross-linking agents. Gels within a few days after mixing with.

[(B) Polyisocyanate]
In the present invention, as the (b) polyisocyanate, a known compound used as a raw material for a polyurethane resin, that is, a compound having at least two isocyanate groups in the molecule can be used without limitation. Examples of such (b) polyisocyanates include aromatic diisocyanates such as phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, 1,6-hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, Trimers of aliphatic or alicyclic structure-containing diisocyanates such as isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, tetramethylxylylene diisocyanate, and the like, and aromatic dicyclic or aliphatic or alicyclic structure-containing diisocyanates And the like can be used. These may be used alone, or two or more of these may be used in combination.

  Among these compounds, 4,4′-dicyclohexylmethane diisocyanate, tolylene diisocyanate, and isophorone diisocyanate are preferable because they can be obtained at low cost. In view of good miscibility with the agent, 4,4′-dicyclohexylmethane diisocyanate is more preferable.

[(C) Anionic group introduction agent]
In the present invention, as the (c) anionic group introducing agent, a known compound used as a raw material for a polyurethane resin can be used. Examples of such an (c) anionic group-introducing agent include polyols containing carboxyl groups such as dimethylolpropionic acid, dimethylolbutanoic acid, dimethylolbutyric acid, dimethylolvaleric acid, and 1,4-butanediol- Polyols containing a sulfonic acid group such as 2-sulfonic acid can be used. In these, the polyol containing a carboxyl group is preferable at a point with easy acquisition, and dimethylol propionic acid is more preferable.

  In the present invention, as a component that reacts with (b) polyisocyanate, in addition to (a) polycarbonate diol and (c) an anionic group introducing agent, a compound containing active hydrogen may be used in combination as an optional component. Good. Examples of such compounds include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, and 2-butyl-2-ethyl-1,3-propane. Diol, 1,4-butanediol, neopentyl glycol, 3-methyl-2,4-pentanediol, 2,4-pentanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 2 -Methyl-2,4-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 3,5-heptanediol, 1,8-octanediol Of 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, bisphenol A Aliphatic diols such as oxides and / or propylene oxide adducts; cycloaliphatic diols such as cyclohexanedimethanol and cyclohexanediol; trimethylolethane, trimethylolpropane, hexitols, pentitols, glycerin, polyglycerin, pentaerythritol , Dipentaerythritol, tetramethylolpropane and other trivalent or higher polyols; melamine, monomethylolmelamine, dimethylolmelamine, trimethylolmelamine, tetramethylolmelamine, pentamethylolmelamine, hexamethylolmelamine, methylated methylolmelamine, butylated methylol Melamines such as melamine and melamine resin are listed.

  These compounds have the effect of increasing the urethane bond concentration of the urethane resin or improving the crosslink density, but when using more than necessary, the viscosity of the urethane prepolymer will be significantly increased, Since it tends to be difficult to disperse in water, the amount used when the compound containing active hydrogen is used is as follows. (B) It contains active hydrogen with respect to 1 equivalent of all isocyanate groups of polyisocyanate. It is preferable that the active hydrogen equivalent of a compound is 0.01-0.3 equivalent, and 0.01-0.2 equivalent is more preferable.

[Amounts of (a), (b), (c)]
In general, when a urethane prepolymer is produced by reacting a polycarbonate diol, a polyisocyanate, and an anionic group introducing agent, the total isocyanate group equivalent (NCO) of the polyisocyanate is included in the polycarbonate diol and the anionic group introducing agent. The terminal structure of the urethane prepolymer obtained depends on the ratio of the total hydroxyl equivalent (OH) (when the above-mentioned optionally added active hydrogen-containing compound is used, the equivalent of the active hydrogen equivalent, hereinafter the same). Different. When NCO / OH is less than 1.0, that is, when the number of hydroxyl groups in the reaction component is excessive, a urethane prepolymer having a terminal hydroxyl group is obtained. When the ratio NCO / OH is 1.0 or more, that is, when the number of isocyanate groups in the reaction component is excessive, a urethane prepolymer whose end groups are isocyanate groups is obtained. Urethane prepolymers whose end groups are isocyanate groups have higher water dispersibility than urethane prepolymers whose end groups are hydroxyl groups, and are easily polymerized by chain extension. Therefore, the urethane prepolymer of the present invention is preferably a urethane prepolymer whose terminal group is an isocyanate group.

  However, when the ratio NCO / OH is 1.0 or more and less than 1.1, a relatively high molecular weight urethane prepolymer is obtained, and such a high molecular weight urethane prepolymer tends to have poor water dispersibility. There is. In this case, the storage stability of the finally obtained aqueous polyurethane resin composition may be deteriorated. Further, when the ratio NCO / OH exceeds 2.5, the product contains a high concentration of isocyanate groups, and therefore, when the obtained prepolymer is dispersed in water, the isocyanate groups and water react to cause carbon dioxide. This may cause problems during production such as rapid foaming. In this case, the adhesion between the coating film made of the aqueous polyurethane resin composition obtained and the substrate may be lowered.

  Therefore, when producing the urethane prepolymer of the present invention, (b) the total isocyanate group equivalent (NCO) of the polyisocyanate component and (a) the total hydroxyl group contained in the polycarbonate diol and (c) the anionic group introducing agent. An amount such that the ratio (NCO / OH) to the equivalent (OH) is preferably 1.1 to 2.5, more preferably 1.2 to 2.0, and particularly preferably 1.3 to 1.8. In a proportion, the above (a) polycarbonate diol, (b) polyisocyanate, and (c) an anionic group introducing agent are blended.

[Acid value of urethane prepolymer]
In the present invention, the dispersibility of the urethane prepolymer in water, the storage stability of the one-part aqueous resin composition obtained by mixing the dispersion of the aqueous polyurethane resin composition and the metal crosslinking agent, the one-part aqueous system From the viewpoint of the balance of physical properties of the resin film obtained from the resin composition, the acid value of the urethane prepolymer is preferably set in the range of 10 to 80 mgKOH / g, more preferably 20 to 50 mgKOH / g. (C) an anionic group introducing agent is used in an amount corresponding to the acid value of such a urethane prepolymer. In addition, the acid value of the above-mentioned urethane prepolymer is a theoretical value calculated | required from the compounding quantity of the reaction component of a urethane prepolymer. As described later, when an inert solvent is used in the production of the urethane prepolymer, the measured value of the acid value of the obtained urethane prepolymer varies from the above theoretical value. The following relationship exists between the above theoretical values and measured values.

Acid value (theoretical value)
= Acid value (measured value) x {(a) + (b) + (c) + solvent: total mass} / {(a) + (b) + (c): total mass}

[catalyst]
In the production of the urethane prepolymer of the present invention, a catalyst can be used as necessary. Examples of such catalysts include N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethylpropylenediamine, N, N, N ′, N ″, N ′. '-Pentamethyldiethylenetriamine, N, N, N', N ", N" -pentamethyl- (3-aminopropyl) ethylenediamine, N, N, N ', N ", N" -pentamethyldipropylene Triamine, N, N, N ′, N′-tetramethylguanidine, 1,3,5-tris (N, N-dimethylaminopropyl) hexahydro-S-triazine, 1,8-diazabicyclo [5.4.0] Undecene-7, triethylenediamine, N, N, N ′, N′-tetramethylhexamethylenediamine, N-methyl-N ′-(2-dimethylaminoethyl) piperazine, N, N′-dimethylpiperazine, dimethyl silane Chlorhexylamine, N-methylmorpholine, N-ethylmorpholine, bis (2-dimethylaminoethyl) ether, N, N-dimethyllaurylamine, 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2- Tertiary amines such as methylimidazole and 1-dimethylaminopropylimidazole can be used.

[Production of urethane prepolymer (step 1)]
In the one-component aqueous resin composition of the present invention, first, a urethane prepolymer is produced (step 1), the urethane prepolymer is dispersed in water (step 2), and then the urethane prepolymer in the aqueous dispersion is (d). It is obtained by producing a water-based polyurethane resin composition by increasing the molecular weight using a chain extender (step 3), and further mixing (e) a metal crosslinking agent in the obtained aqueous dispersion (step 4). .

  The urethane prepolymer comprises (a) a polyol component, (b) a polyisocyanate component, (c) an anionic group introducing agent, a compound containing any active hydrogen and / or a catalyst, in any inert solvent. It is obtained by reacting in the range of 60 to 150 ° C. for 1 to 10 hours in the presence. As the inert solvent used at this time, acetone, methyl ethyl ketone, dioxane, tetrahydrofuran, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or the like having a high affinity for water can be used. When using a solvent having a boiling point of 100 ° C. or lower, it is preferable to synthesize the aqueous polyurethane resin of the present invention and then remove the solvent by distillation under reduced pressure or the like. Although the usage-amount of a solvent is not restrict | limited in particular, Preferably it is 3-200 mass parts with respect to 100 mass parts of whole quantity of the raw material of a urethane prepolymer.

[Water dispersion of urethane prepolymer (step 2)]
In the present invention, the urethane prepolymer thus obtained is dispersed in water and then reacted with (d) a chain extender. In the present invention, the method for dispersing the urethane prepolymer in water is not particularly limited. For example, the following prepolymer mixing method and phase inversion method can be used.

(Prepolymer mixing method)
An anionic group neutralizing agent is added to the urethane prepolymer, and the resulting urethane prepolymer mixture is poured into water and dispersed in water using means such as a homomixer or a disper. In addition, an anionic group neutralizing agent / emulsifier can be added to water in advance before the urethane prepolymer mixture is charged.

(Phase inversion method)
An anionic group neutralizing agent is added to the urethane prepolymer, water is further added, and the mixture is stirred as necessary using a means such as a homomixer or a disper to obtain an aqueous dispersion of the urethane prepolymer. In addition, water to which an anionic group neutralizing agent and / or an emulsifier has been added in advance can be added.

(Anionic group neutralizer)
Examples of the anionic group neutralizing agent include trialkylamines such as trimethylamine, triethylamine, and tributylamine; N, N-dimethylethanolamine, N, N-dimethylpropanolamine, N, N-dipropylethanolamine, 1-dimethyl Tertiary amine compounds of trialkanolamines such as N, N-dialkylalkanolamines such as amino-2-methyl-2-propanol, N-alkyl-N, N-dialkanolamines and triethanolamine; ammonia; Basic compounds such as trimethylammonium hydroxide, sodium hydroxide, potassium hydroxide, and lithium hydroxide can be used. These compounds can be used alone, or two or more of these compounds can be used in combination.

Among these anionic group neutralizing agents, a highly volatile anionic group neutralizing agent that is easily dissociated by heat is preferable from the viewpoint of improving the weather resistance and water resistance of the dried product. Particularly preferred anionic group neutralizing agents are trimethylamine and / or triethylamine.
In view of the storage stability of the one-part aqueous resin composition of the present invention, the mechanical properties of the coating film comprising this, the water resistance, etc., the amount of the anionic group neutralizing agent used is 1 equivalent of the anionic group. Preferably it is 0.5-2.0 equivalent, More preferably, it is 0.8-1.5 equivalent.

(emulsifier)
A known surfactant can be used as the emulsifier. For example, general anionic surfactants and nonionic surfactants as surfactants, cations such as primary amine salts, secondary amine salts, tertiary amine salts, quaternary amine salts and pyridinium salts An amphoteric surfactant such as a surfactant, betaine type, sulfate type and sulfonic acid type can be used.

  Examples of the anionic surfactant include alkyl sulfates such as sodium dodecyl sulfate, potassium dodecyl sulfate, and ammonium dodecyl sulfate; polyoxyethylene ether sulfates such as sodium dodecyl polyglycol ether sulfate and ammonium polyoxyethylene alkyl ether sulfate; Alkyl sulfonates such as ricinolate, alkali metal salt of sulfonated paraffin, ammonium salt of sulfonated paraffin; fatty acid salts such as sodium laurate, triethanolamine oleate, triethanolamine abiate; sodium benzenesulfonate, alkali phenol hydroxy Alkyl aryl sulfos such as alkali metal sulfates of ethylene It can be used over door class. In addition, high alkyl naphthalene sulfonate, naphthalene sulfonate formalin condensate, dialkyl sulfosuccinate, polyoxyethylene alkyl sulfate salt, polyoxyethylene alkyl aryl sulfate salt, polyoxyethylene ether phosphate, polyoxyethylene alkyl ether acetic acid A salt, an N-acylamino acid salt, an N-acylmethyltaurine salt, and the like can also be used.

  As the nonionic surfactant, fatty acid partial esters of polyhydric alcohols such as sorbitan monolaurate and sorbitan monooleate, polyoxyethylene glycol fatty acid esters, and polyglycerin fatty acid esters can be used. Furthermore, ethylene oxide and / or propylene oxide adduct of alcohol having 1 to 18 carbon atoms, ethylene oxide and / or propylene oxide adduct of alkylphenol, ethylene oxide and / or propylene oxide adduct of alkylene glycol and / or alkylene diamine, etc. Can be used.

  Examples of the alcohol having 1 to 18 carbon atoms constituting the nonionic surfactant include methanol, ethanol, propanol, 2-propanol, butanol, 2-butanol, tertiary butanol, amyl alcohol, isoamyl alcohol, tertiary amyl alcohol, Examples include hexanol, octanol, decane alcohol, lauryl alcohol, myristyl alcohol, palmityl alcohol, and stearyl alcohol.

  Examples of the alkylphenol include phenol, methylphenol, 2,4-di-tert-butylphenol, 2,5-di-tert-butylphenol, 3,5-di-tert-butylphenol, and 4- (1,3-tetramethylbutyl) phenol. 4-isooctylphenol, 4-nonylphenol, 4-tert-octylphenol, 4-dodecylphenol, 2- (3,5-dimethylheptyl) phenol, 4- (3,5-dimethylheptyl) phenol, naphthol, bisphenol A, And bisphenol F and the like.

  Examples of the alkylene glycol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,6-hexanediol, etc. It is.

  The alkylene diamine is, for example, a compound in which the alcoholic hydroxyl group of the alkylene glycol described above is substituted with an amino group. As the ethylene oxide and propylene oxide adduct, both random adducts and block adducts can be used.

  Examples of the cationic surfactant include lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, didecyldimethylammonium chloride, laurylbenzyldimethylammonium chloride, didecyldimethylammonium chloride, alkylpyridinium bromide and imidazolinium. Laurate or the like can be used.

  Examples of the amphoteric surfactant include coconut oil fatty acid amidopropyldimethylacetate betaine, lauryldimethylamino acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxymethylimidazolinium betaine, laurylhydroxysulfobetaine, lauroylamidoethylhydroxyethyl. Betaine-type amphoteric surfactants such as carboxymethyl betaine and metal salts of hydroxypropyl phosphate, amino acid-type amphoteric surfactants such as metal salts of β-laurylaminopropionic acid, sulfate-type amphoteric surfactants and sulfonic-acid-type amphoteric Surfactants can be used.

  Nonionic surfactants are preferred as emulsifiers because they are easily available and inexpensive, fatty acid partial esters of polyhydric alcohols such as sorbitan monolaurate and sorbitan monooleate, ethylene oxides of alcohols having 1 to 18 carbon atoms, and A propylene oxide adduct is more preferred.

  Although the usage-amount of the said emulsifier is not restrict | limited, From viewpoints, such as the water resistance of the coating film which consists of an aqueous polyurethane resin composition, Preferably it is 0-30 mass parts with respect to 100 mass parts of total amounts of a urethane prepolymer composition. More preferably, it is 0-20 mass parts. When emphasizing the water resistance of the coating film made of the aqueous polyurethane resin composition, it is preferable to minimize the amount of the emulsifier used.

[Production of water-based polyurethane resin composition (step 3)]
In the present invention, the urethane prepolymer in the urethane prepolymer dispersion obtained by the above method is reacted with the (d) chain extender to produce a polyurethane resin in the dispersion. Thus, an aqueous polyurethane resin composition in which the polyurethane resin is dispersed in water is obtained.

  In the present invention, (d) a mixture of the chain extender and the urethane prepolymer is heated in the range of 5 to 50 ° C. for 1 minute to 6 hours, whereby the isocyanate groups remaining in the urethane prepolymer and (d ) React with a chain extender to increase the molecular weight of the urethane prepolymer. By increasing the molecular weight of such a urethane prepolymer, an aqueous polyurethane resin composition giving a film having good physical properties can be obtained.

((D) chain extender)
As said (d) chain extender, the compound normally used for manufacture of a polyurethane resin can be used without a restriction | limiting. Examples of such (d) chain extender include mensendiamine, isophoronediamine, norbornenediamine, aminoethylaminoethanol, bis (4-amino-3-methyldicyclohexyl) methane, diaminodicyclohexylmethane, and bis (aminomethyl). ) Alicyclic diamines such as cyclohexane, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxaspiro (5,5) undecane; m-xylenediamine, α- (m / p-aminophenyl) ethylamine, m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodimethyldiphenylmethane, diaminodiethyldiphenylmethane, dimethylthiotoluenediamine, diethyltoluenediamine, α, α'-bis (4-aminophenyl) Polyamines of aromatic diamines such as) -p-diisopropylbenzene can also be used. Further, succinic acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, phthalic acid dihydrazide, 1,6-hexamethylenebis (N, N-dimethylsemicarbazide), 1,1,1 ′, 1′-tetramethyl-4,4 ′ Hydrazines such as-(methylene-di-para-phenylene) disemicarbazide, hydrazine hydrate, and water can also be used.

  Among these compounds, diamines, hydrazides, hydrated hydrazine and water are preferable, and ethylenediamine, adipic acid dihydrazide, hydrated hydrazine and water are particularly preferable.

  (D) The amount of the chain extender used is not particularly limited, but is included in the (A) urethane prepolymer before the chain extension reaction (step 3) from the viewpoint of the physical properties of the coating film comprising the aqueous resin composition of the present invention. The amount that the ratio of the isocyanate reactive group equivalent contained in the (d) chain extender to the isocyanate group equivalent is in the range of 0.1 to 1.0 is preferred. When the amount is less than 0.1 equivalent, the urethane prepolymer does not have a high molecular weight and the physical properties of the coating film tend to be remarkably deteriorated. When the amount is more than 1.0 equivalent, unreacted (d ) The remaining chain extender tends to cause problems such as a decrease in storage stability and an increase in pH.

(Water-based polyurethane resin composition)
The aqueous polyurethane resin composition thus obtained contains a specific polyurethane resin as a main component. This specific polyurethane resin is obtained by reacting the urethane prepolymer obtained by reacting the above-mentioned (a) polycarbonate diol, (b) polyisocyanate, and (c) an anionic group introducing agent with the above-mentioned (d) chain extension. High molecular weight with an agent. The repeating unit of such a polyurethane resin is not uniform, and the structure and the number of repetitions are varied. Therefore, the structure of the polyurethane resin is very complicated. For this reason, the structure of the polyurethane resin cannot be uniformly expressed by a certain general formula. Therefore, in the present invention, the polyurethane resin is prepared by combining a urethane prepolymer that is a reaction product of (a) polycarbonate diol, (b) polyisocyanate, and (c) an anionic group introducing agent with (d) a chain extender. It must be defined by the expression “polyurethane resin obtained by reaction”.

[Production of one-part aqueous resin composition (step 4)]
The one-component aqueous resin composition of the present invention can be produced by mixing the water-based polyurethane resin composition with (e) a metal crosslinking agent.

((E) Metal crosslinking agent)
The (e) metal crosslinking agent used in the present invention is a compound that reacts with the polyurethane resin in the aqueous polyurethane resin composition to form a crosslinked structure. With such a crosslinked structure, the physical properties and various performances (alkali resistance, solvent resistance, etc.) of the water-based polyurethane resin composition can be improved.

Examples of such (e) metal cross-linking agent include zirconium acetate, zirconium propionate, zirconium chloride, zirconium oxychloride, hydroxy zirconium chloride, zirconium nitrate, basic zirconium carbonate, zirconium hydroxide, ammonium zirconium carbonate, zirconium carbonate. Zirconium compounds such as potassium, zirconium sulfate, ammonium zirconium fluoride and zirconium phosphate; Magnesium compounds such as magnesium chloride, magnesium sulfate, magnesium nitrate, magnesium phosphate and magnesium acetate; calcium chloride, calcium perchlorate and calcium sulfate Calcium compounds such as calcium nitrate, calcium phosphate and calcium acetate; titanium compounds such as titanium chloride and titanium sulfate; ammonium carbonate Zinc compounds such as zinc; boron compounds such as borate, aluminum chloride, hydrate of aluminum chloride, aluminum hydroxide, basic polyaluminum hydroxide compound, aluminum-based compounds such as alum and the like.
Among these metal cross-linking agents, zirconium-based compounds are preferable and zirconium carbonate is particularly preferable in that the reactivity with a polyurethane resin in water is good.

  The mixing method of the water-based polyurethane resin composition and (e) the metal crosslinking agent is not limited as long as it is a normal method with stirring. The amount of the (e) metal crosslinking agent used is generally 0.1 to 15% by mass with respect to the total amount of the polyurethane resin and the metal crosslinking agent contained in the aqueous polyurethane resin composition. From the viewpoint of the balance between the storage stability of the water-based polyurethane resin composition and the physical properties of the resin film, the amount of the (e) metal crosslinking agent is preferably 1 to 12% by mass, more preferably 3 -10 mass%.

(Additive)
Additives can be added to the one-component aqueous resin composition of the present invention as long as the effects of the present invention are not impaired. As the additive, various general resin additives can be used without limitation. Examples of such additives include various weathering agents (hindered amine light stabilizers, ultraviolet absorbers and antioxidants), coupling agents that particularly strengthen adhesion to substrates, adhesion promoters other than coupling agents, Inorganic colloidal sol such as colloidal silica or colloidal alumina, tetraalkoxysilane and its condensation polymer, chelating agent, epoxy compound, pigment, dye, film-forming aid, curing agent, external cross-linking agent, viscosity modifier, leveling agent, antifoaming Agent, anticoagulant, radical scavenger, heat resistance imparting agent, inorganic or organic filler, plasticizer, lubricant, antistatic agent such as fluorine or siloxane, reinforcing agent, catalyst, thixotropic agent, waxes, Antifogging agents, antibacterial agents, antifungal agents, anticorrosive agents, rust inhibitors, and the like can be used.

  Examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5′-methylenebis (2-hydroxy-4-methoxybenzophenone). 2-hydroxybenzophenones such as 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-3, 5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5 -Dicumylphenyl) benzotriazole, 2,2'-methylenebis (4- 3-octyl-6-benzotriazolylphenol), 2- (2-hydroxy-3-tert-butyl-5-carboxyphenyl) benzotriazole polyethylene glycol ester, 2- [2-hydroxy-3- (2-acryloyl) Oxyethyl) -5-methylphenyl] benzotriazole, 2- [2-hydroxy-3- (2-methacryloyloxyethyl) -5-tert-butylphenyl] benzotriazole, 2- [2-hydroxy-3- (2) -Methacryloyloxyethyl) -5-tert-octylphenyl] benzotriazole, 2- [2-hydroxy-3- (2-methacryloyloxyethyl) -5-tert-butylphenyl] -5-chlorobenzotriazole, 2- [ 2-hydroxy-5- (2-methacryloyloxyethyl) phenyl] benzene Nzotriazole, 2- [2-hydroxy-3-tert-butyl-5- (2-methacryloyloxyethyl) phenyl] benzotriazole, 2- [2-hydroxy-3-tert-amyl-5- (2-methacryloyl) Oxyethyl) phenyl] benzotriazole, 2- [2-hydroxy-3-tert-butyl-5- (3-methacryloyloxypropyl) phenyl] -5-chlorobenzotriazole, 2- [2-hydroxy-4- (2) -Methacryloyloxymethyl) phenyl] benzotriazole, 2- [2-hydroxy-4- (3-methacryloyloxy-2-hydroxypropyl) phenyl] benzotriazole, 2- [2-hydroxy-4- (3-methacryloyloxypropyl) ) Phenyl] benzotriazole and the like 2- (2-hydroxyphene) B) benzotriazoles; 2- (2-hydroxy-4-methoxyphenyl) -4,6-diphenyl-1,3,5-triazine, 2- (2-hydroxy-4-hexyloxyphenyl) -4,6 -Diphenyl-1,3,5-triazine, 2- (2-hydroxy-4-octoxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [ 2-hydroxy-4- (3-C12-C13 mixed alkoxy-2-hydroxypropoxy) phenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [2- Hydroxy-4- (2-acryloyloxyethoxy) phenyl] -4,6-bis (4-methylphenyl) -1,3,5-triazine, 2- (2,4-dihydroxy-3-allylphene) ) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-hexyloxyphenyl) -1, 2- (2-hydroxyphenyl) -4,6-diaryl-1,3,5-triazines such as 3,5-triazine; phenyl salicylate, resorcinol monobenzoate, 2,4-di-tert-butylphenyl-3, 5-di-tert-butyl-4-hydroxybenzoate, octyl (3,5-di-tert-butyl-4-hydroxy) benzoate, dodecyl (3,5-di-tert-butyl-4-hydroxy) benzoate, tetradecyl (3 5-di-tert-butyl-4-hydroxy) benzoate, hexadecyl (3,5-di-tert-butyl-4-hydroxy) benzoate, octadecyl (3,5-di) Benzoates such as tert-butyl-4-hydroxy) benzoate and behenyl (3,5-ditert-butyl-4-hydroxy) benzoate; 2-ethyl-2′-ethoxyoxanilide, 2-ethoxy-4′- Substituted oxanilides such as dodecyl oxanilide; Cyanoacrylates such as ethyl-α-cyano-β, β-diphenyl acrylate, methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate; and various Metal salts or metal chelates such as nickel or chromium salts or chelates are used.

  As the antioxidant, phosphorus antioxidants, phenol antioxidants, sulfur antioxidants can be used. Examples of phosphorus antioxidants include triphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris (2,5-di-tert-butylphenyl) phosphite, and tris (nonylphenyl). Phosphite, tris (dinonylphenyl) phosphite, tris (mono, dimixed nonylphenyl) phosphite, diphenyl acid phosphite, 2,2′-methylenebis (4,6-ditertiarybutylphenyl) octyl phosphite, Diphenyldecyl phosphite, diphenyloctyl phosphite, di (nonylphenyl) pentaerythritol diphosphite, phenyl diisodecyl phosphite, tributyl phosphite, tris (2-ethylhexyl) phosphite, tridecyl phosphite, trilauryl phosphite, Butyl acid phosphite, dilauryl acid phosphite, trilauryl trithiophosphite, bis (neopentylglycol) -1,4-cyclohexanedimethyldiphosphite, bis (2,4-ditertiarybutylphenyl) pentaerythritol diphos Phyto, bis (2,5-ditertiarybutylphenyl) pentaerythritol diphosphite, bis (2,6-ditertiarybutyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-dicumyl) Phenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, tetra (mixed alkyl of C12 alkyl to C15 alkyl) -4,4'-isopropylidenediphenyl phosphite, bis [2,2'-methylenebis (4 6-dia Milphenyl)]-isopropylidene diphenyl phosphite, tetratridecyl-4,4′-butylidenebis (2-tert-butyl-5-methylphenol) diphosphite, hexa (tridecyl) -1,1,3-tris (2- Methyl-5-tert-butyl-4-hydroxyphenyl) butane triphosphite, tetrakis (2,4-ditert-butylphenyl) biphenylene diphosphonite, tris (2-[(2,4,7,9-tetrakis) Tert-butyldibenzo [d, f] [1,3,2] dioxaphosphin-6-yl) oxy] ethyl) amine, 9,10-dihydro-9-oxa-10-phosphaphenanthrene- 10-oxide, tris (2-[(2,4,8,10-tetrakis tert-butyldibenzo [d, f] [1,3,2] dioxaphos Epin-6-yl) oxy] ethyl amine, 2- (1,1-dimethylethyl) -6-methyl-4- [3-[[2,4,8,10-tetrakis (1,1-dimethylethyl) Dibenzo [d, f] [1,3,2] dioxaphosphin-6-yl] oxy] propyl] phenol and 2-butyl-2-ethylpropanediol-2,4,6-tritert-butylphenol Monophosphite or the like can be used.

  Examples of the phenol-based antioxidant include 2,6-ditertiarybutyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-ditertiarybutyl-4- Hydroxyphenyl) propionate, distearyl (3,5-ditertiarybutyl-4-hydroxybenzyl) phosphonate, tridecyl 3,5-ditertiarybutyl-4-hydroxybenzylthioacetate, thiodiethylenebis [(3,5 -Di-tert-butyl-4-hydroxyphenyl) propionate], 4,4'-thiobis (6-tert-butyl-m-cresol), 2-octylthio-4,6-di (3,5-di-tert-butyl) -4-hydroxyphenoxy) -s-triazine, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), bis [3,3- (4-hydroxy-3-tert-butylphenyl) butyric acid] glycol ester, 4,4′-butylidenebis (2,6-ditert-butylphenol), 4,4′-butylidenebis (6-tert-butyl- 3-methylphenol), 2,2′-ethylidenebis (4,6-di-tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, bis [2-tert-butyl-4-methyl-6- (2-hydroxy-3-tert-butyl-5-methylbenzyl) phenyl] terephthalate, 1,3,5-tris (2,6-dimethyl-3-hydroxy -4-tert-butylbenzyl) isocyanurate, 1,3,5-tris (3,5-ditert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tri (3,5-di-tert-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1,3,5-tris [(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl Oxyethyl] isocyanurate, tetrakis [methylene-3- (3 ′, 5′-ditert-butyl-4′-hydroxyphenyl) propionate] methane, 2-tert-butyl-4-methyl-6- (2-acrolate) Yloxy-3-tert-butyl-5-methylbenzyl) phenol, 3,9-bis [2- (3-tert-butyl-4-hydroxy-5-methylhydrocinnamoyloxy) -1,1-dimethylethyl ] -2,4,8,10-tetraoxaspiro [5.5] undecane, triethylene glycol bis [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propyl Lopionate], tocopherol and the like can be used.

  Examples of the sulfur-based antioxidant include dialkylthiodipropionates such as dilauryl, dimyristyl, myristyl stearyl, and distearyl esters of thiodipropionic acid, and pentaerythritol tetra (β-dodecyl mercaptopropionate). The β-alkyl mercaptopropionic esters of polyols can be used.

  The amount of the weathering agent (hindered amine light stabilizer, ultraviolet absorber and antioxidant) used is preferably 0.001 to 10 parts by mass, more preferably 100 parts by mass based on the solid content of the aqueous polyurethane resin composition. 0.01 to 5 parts by mass. If the amount of the weathering agent is less than 0.001 part by mass with respect to 100 parts by mass of the solid content, a sufficient addition effect may not be obtained. If the amount of the weathering agent is more than 10 parts by mass with respect to 100 parts by mass of the solid content, the water dispersion stability and the physical properties of the coating film may be adversely affected.

  As a method of adding these weathering agents, a method of adding to a urethane raw material polyol, a method of adding to a urethane prepolymer, a method of adding to a water phase during water dispersion of the urethane prepolymer, a method of adding after water dispersion Either is fine. In terms of easy operation, a method of adding to the raw material polyol and a method of adding to the urethane prepolymer are preferred.

  Examples of the coupling agent include γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -N′-β- (amino Ethyl) -γ-aminopropyltriethoxysilane, γ-anilinopropyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, vinyltriethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-isocyanatopropyl Silane couplings such as triethoxysilane Agents: isopropyl triisostearoyl titanate, isopropyl tri-n-dodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra ( 2,2-diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyldimethacryloyl Isostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri (di Octyl phosphate) titanate, isopropyl tricumyl phenyl titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate, tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetrakis (2-ethylhexyl) titanate, tetrastearyl titanate, tetra Methyl titanate, diethoxybis (acetylacetonato) titanium, diisopropylbis (acetylacetonato) titanium, diisopropoxybis (ethylacetoacetate) titanium, isopropoxy (2-ethyl-1,3-hexanediolato) titanium, di ( 2-ethylhexoxy) bis (2-ethyl-1,3-hexanediolato) titanium, di-n-butoxybis (triethanolaminato) titanium, tetra Titanium coupling agents such as acetylacetonate titanium, hydroxybis (lactato) titanium, dicumylphenyloxyacetate titanate, diisostearoylethylene titanate; zirconium tributoxy systemate, tetra (2,2-diallyloxymethyl) butyldi (ditridecyl) ) Phosphitozirconate, Neopentyl (diallyl) oxytrineodecanoyl zirconate, Neopentyl (diallyl) oxytri (dodecyl) benzene-sulfonyl zirconate, Neopentyl (diallyl) oxytri (dioctyl) phosphato zirconate, Neopentyl (diallyl) oxytri (Dioctyl) pyro-phosphato zirconate, neopentyl (diallyl) oxytri (N-ethylenediamino) ethyl zirconate, neo Nethyl (diallyl) oxytri (m-amino) phenyl zirconate, neopentyl (diallyl) oxytrimethacrylic zirconate, neopentyl (diallyl) oxytriacrylic zirconate, dineopentyl (diallyl) oxydiparaaminobenzoyl zirconate, dineopentyl (diallyl) oxydi (3-mercapto) propyl zirconate, tetranormal propoxyzirconium, tetranormalbutoxyzirconium, zirconium 2,2-bis (2-propenolatomethyl) butyrate, zirconium tetraacetylacetonate, zirconium tributoxyacetylacetonate, zirconium di Butoxybis (acetylacetonate), zirconium dibutoxybis (acetylacetonate), zirconium trib Acetoacetate, can be mentioned zirconium coupling agents such as zirconium monobutoxy acetylacetonate bis (ethylacetoacetate).

  Among these coupling agents, it is preferable to use a silane coupling agent from the viewpoint of improving the adhesion to the metal surface and the compatibility of the aqueous polyurethane resin composition, and it is coupled to the urethane resin skeleton. In view of incorporating a functional group, it is more preferable to use a silane coupling agent containing an amino group.

  The amount of the coupling agent used is not particularly limited as long as it is an effective amount or more, but (a) a polycarbonate diol, (b) a polyisocyanate, (c) an anionic group introducing agent, and an active hydrogen that is optionally blended. Preferably it is 0.01-1 mass% with respect to the total amount of the compound to contain, a catalyst, and an additive, More preferably, it is 0.1-0.5 mass%.

  Examples of the adhesion promoter other than the coupling agent include benzimidazole, benzoxazole, benzthiazole, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzthiazole, 3-morpholinomethyl-1-phenyl- Examples include triazole-2-thione, 5-amino-3-morpholinomethyl-thiazole-2-thione, 2-mercapto-5-methylthio-thiadiazole, triazole, tetrazole, benzotriazole, carboxybenzotriazole, amino group-containing benzotriazole, and the like. It is done. Of these, benzotriazole is preferably used.

  The use amount of the adhesion promoter other than the coupling agent is not particularly limited as long as it is an effective amount or more, but (a) polycarbonate diol, (b) polyisocyanate, (c) an anionic group introducing agent, and optionally blended. Preferably, the content is 0.01 to 1% by mass, more preferably 0.1 to 0.5% by mass, based on the total amount of the active hydrogen-containing compound, catalyst and additive.

(One-part water-based resin composition)
Thus, the one-component aqueous resin composition of the present invention is finally obtained by mixing the aqueous urethane resin composition, the (e) metal cross-linking agent, and optionally the additive. The one-component aqueous resin composition of the present invention has good storage stability without separation of the metal crosslinking agent or gelation of the urethane resin over time. For this reason, when the one-pack type aqueous resin composition of the present invention is used as a paint, it is not necessary to weigh and mix the metal cross-linking agent immediately before construction, and it can be directly applied to an object to be coated. . Therefore, the one-component water-based resin composition of the present invention is excellent in handleability and used as a paint with stable quality.

[Usage]
The one-part aqueous resin composition of the present invention is, for example, a thermal paper coating agent, an inkjet recording paper coating agent, a printing ink binder, a steel plate coating agent, an agricultural film coating agent, glass, slate, concrete. It can be used as a coating agent for a substrate such as an inorganic structural material coating material, a wood coating material, and a fiber treatment agent. In these, it is preferably used as a coating material for inorganic structural materials such as concrete.

  Examples of the coating method of the coating agent using the aqueous resin composition of the present invention include brush coating, roller coating, spray coating, gravure coating, reverse roll coating, air knife coating, bar coating, curtain roll coating, dip coating, Any means such as a rod coat or a doctor blade coat may be used. The aqueous resin composition of the present invention is applied to a substrate by means appropriately selected from these.

  Hereinafter, the present invention will be specifically described by way of examples. In the following examples and the like,% is based on mass unless otherwise specified. The raw materials used in Examples and Comparative Examples are shown below.

(Polyol)
UH-200: 1,6-hexanediol-based number average molecular weight 2000 (a) polycarbonate diol, manufactured by Ube Industries, Ltd. S-6002: 1,6-hexanediol-based number average molecular weight 2000 (a ) Polycarbonate diol, manufactured by Asahi Kasei Chemicals Co., Ltd. • G-3451: 1,3-propanediol and 1,4-butanediol based number average molecular weight 2000 (a) Polycarbonate diol: Asahi Kasei Chemicals Co., Ltd. Y9- 10: Polyester diol having a number average molecular weight of 1000, which is a condensate of neopentyl glycol and adipic acid (for comparison), ADEKA Co., Ltd./Poly-THF 1000: Polytetraethylene ether glycol having a number average molecular weight of 1000 (for comparison)
((B) Polyisocyanate)
-H-MDI: 4,4'-dicyclohexylmethane diisocyanate-IPDI: isophorone diisocyanate ((c) anionic group introducing agent)
DMPA: dimethylolpropionic acid ((d) chain extender)
・ EDA: Ethylenediamine (crosslinking agent)
AZC: ammonium zirconium carbonate (2 (NH ₄ ) .C ₂ H ₂ O ₈ Zr): (e) metal crosslinking agent V-02-L2: 40% polycarbodiimide crosslinking agent-containing aqueous solution, Nisshinbo Chemical Co., Ltd. Made (for comparison)
(Solvents and additives)
-NMP: N-methylpyrrolidone-SE-21: Silicone-based antifoaming agent, manufactured by Asahi Kasei Wacker Silicone Co., Ltd.-Suraoff 620: Preservative, manufactured by Takeda Pharmaceutical Co., Ltd.

  The aqueous resin compositions obtained in the examples were evaluated for storage stability, corrosion resistance, chemical resistance, and alkali resistance by the following methods.

(Storage stability)
The one-component aqueous resin composition was placed in a 500 ml glass bottle, allowed to stand at 50 ° C. for 2 weeks, and the change in appearance was visually evaluated. The evaluation results were determined according to the following criteria.
Pass: There is no change in appearance, and a uniform solution state is maintained.
Fail: Inhomogeneity was observed in the solution. Alternatively, some or more gelation was observed.

(Corrosion resistance)
The one-pack type aqueous resin composition was applied in a thickness of 1 μm on an untreated electrogalvanized steel sheet. This was heated for 3 seconds in an atmosphere of 300 ° C. and heated so that the maximum temperature reached by the steel sheet was 80 ° C. Thus, a test piece having a urethane resin film adhered thereto was obtained. About this test piece, the salt spray process (SST) based on JISZ2371 was performed for 24 hours. The test piece that had undergone this treatment was observed for rust occurrence and evaluated according to the following evaluation criteria.
A: Rust generation area is less than 5% B: Rust generation area is 5% or more and less than 50% C: Rust generation area is 50% or more

(chemical resistance)
The same test piece prepared in the above corrosion resistance evaluation was placed in a rubbing tester (FR-II; manufactured by Suga Test Instruments Co., Ltd.), and absorbent cotton impregnated with ethanol was rubbed 20 times with a 200 g load. L value which shows the color tone of the urethane film of the test piece before and behind this process was measured with the spectrocolorimeter (CM-3700d: Konica Minolta Japan Co., Ltd. product). About the chemical resistance of the film | membrane of a test piece, the difference (DELTA) L of the L value before and behind a process was determined on the following references | standards.
A: Particularly good. ΔL is less than 0.2 B: Good. ΔL is 0.2 or more and less than 2.0 C: Bad. △ L is 2.0 or more

(Alkali resistance)
The same test piece prepared in the above corrosion resistance evaluation was immersed in a 1% aqueous sodium hydroxide solution at 60 ° C. for 1 minute. Changes in the urethane film before and after this treatment were evaluated according to the following evaluation criteria.
A: Good. No change in film.
B: Somewhat bad. Less than 50% of the entire film is peeled off.
C: Bad. More than 50% of the entire film is peeled off.

[Example 1]
To a five-neck separable round bottom flask equipped with a Dimroth, a stirring blade, and a nitrogen line, 204 g of UH-200, 103 g of H-MDI, 19.5 g of dimethylolpropionic acid, 144.8 g of NMP were added, The mixture was reacted for 4 hours to produce a urethane prepolymer containing NMP. When the acid value of the urethane prepolymer containing NMP was measured, it was 17.5 mgKOH / g. Since this acid value includes NMP, the actual acid value of the urethane prepolymer alone is calculated to be 25 mgKOH / g.

  To a 2 L disposable cup, add 527.9 g of water at 40 ° C., 14.7 g of triethylamine, and 0.3 g of SE-21. After stirring for 5 minutes with a disper, 452.6 g of the urethane prepolymer was added over 2 minutes. And stirred for 30 minutes. Thereafter, 19.6 g of an aqueous solution of ethylenediamine / water = 1/3 (mass ratio) was added, and the mixture was further stirred for 30 minutes. Thereafter, 1.8 g of Sura-off 620 was added and allowed to stir for 10 minutes. Further, 133.6 g of a 13% zirconium ammonium carbonate aqueous solution was added to the ammonium zirconium carbonate in an amount of 5% with respect to the total mass of the polyurethane resin component and zirconium ammonium carbonate. Corresponding amount) and stirred for 10 minutes to obtain a one-component aqueous resin composition A-1. Table 1 shows the evaluation of storage stability, corrosion resistance, chemical resistance, and alkali resistance of the obtained A-1.

[Example 2]
Example 1 except that the addition amount of 13% aqueous ammonium zirconium carbonate solution was changed to 282.1 g (an amount corresponding to 10% ammonium zirconium carbonate with respect to the total mass of the polyurethane resin component and ammonium zirconium carbonate). In the same manner as described above, a one-component aqueous resin composition A-2 was obtained. Table 1 shows the evaluation of the storage stability, corrosion resistance, chemical resistance, and alkali resistance of the obtained A-2.

[Example 3]
Example 1 except that the addition amount of 13% aqueous ammonium zirconium carbonate solution was changed to 78.5 g (amount corresponding to 3% ammonium zirconium carbonate with respect to the total mass of the polyurethane resin component and ammonium zirconium carbonate). In the same manner as above, a one-component aqueous resin composition A-3 was obtained. Table 1 shows the evaluation of storage stability, corrosion resistance, chemical resistance and alkali resistance of the obtained A-3.

[Example 4]
To a 5-neck separable round bottom flask equipped with a Dimroth, a stirring blade, and a nitrogen line, add 730 g of S-6002, 217.7 g of IPDI, 35.2 g of dimethylolpropionic acid, 393.5 g of NMP, and 120 ° C. After reacting for 4 hours, the reaction system was cooled to 60 ° C., and 26.5 g of triethylamine was added to produce a urethane prepolymer containing NMP. It was 10.5 mgKOH / g when the acid value of the urethane prepolymer containing NMP before triethylamine addition was measured. Since the value of this acid value includes NMP, the acid value of the urethane prepolymer alone before the actual addition of triethylamine is 15 mgKOH / g as a calculated value.

  To a 5 L disposable cup, 1277 g of 40 ° C. water and 0.8 g of SE-21 were added and stirred for 5 minutes with a disper. Then, 1277 g of the urethane prepolymer was added over 5 minutes and stirred for 30 minutes. Thereafter, 49.3 g of an aqueous solution of ethylenediamine / water = 1/3 (mass ratio) was added, and the mixture was further stirred for 30 minutes. Thereafter, 416.9 g of a 13% zirconium ammonium carbonate aqueous solution (an amount corresponding to 5% zirconium ammonium carbonate with respect to the total mass of the polyurethane resin component and ammonium zirconium carbonate) was added, and the mixture was stirred for 10 minutes. Resin composition A-4 was obtained. Table 1 shows the evaluation of storage stability, corrosion resistance, chemical resistance and alkali resistance of the obtained A-4.

[Example 5]
550 g of G-3452, 162.7 g of IPDI, 35.2 g of dimethylolpropionic acid, and 297 g of NMP were added to a five-neck separable round bottom flask equipped with a Dimroth, stirring blade and nitrogen line at 120 ° C. for 4 hours. After that, the reaction system was cooled to 60 ° C., and 19.9 g of triethylamine was added to produce a urethane prepolymer containing NMP. It was 10.5 mgKOH / g when the acid value of the urethane prepolymer containing NMP before triethylamine addition was measured. Since the value of this acid value includes NMP, the acid value of the urethane prepolymer alone before the actual addition of triethylamine is 15 mgKOH / g as a calculated value.

  After adding 449.7 g of water at 40 ° C., 1.5 g of triethylamine and 0.1 g of SE-21 to a 2 L disposable cup, and stirring with a disper for 5 minutes, 449.7 g of the urethane prepolymer was added over 5 minutes. And stirred for 30 minutes. Thereafter, 15.9 g of an aqueous solution of ethylenediamine / water = 1/3 (mass ratio) was added and further stirred for 30 minutes. Thereafter, 144.1 g of a 13% aqueous zirconium carbonate solution (amount corresponding to 5% zirconium ammonium carbonate with respect to the total mass of the polyurethane resin component and ammonium zirconium carbonate) was added, and the mixture was stirred for 10 minutes. Resin composition A-5 was obtained. Table 1 shows the evaluation of storage stability, corrosion resistance, chemical resistance and alkali resistance of the obtained A-5.

[Comparative Example 1]
To a 5-neck separable round bottom flask equipped with a Dimroth, stirring blade, and nitrogen line, add 400 g of Y9-10, 408 g of H-MDI, 58.9 g of dimethylolpropionic acid, and 387 g of NMP, and 120 ° C. for 4 hours. Then, the reaction system was cooled to 60 ° C., and 44.7 g of triethylamine was added to produce a urethane prepolymer containing NMP. It was 19 mgKOH / g when the acid value of the urethane prepolymer containing NMP before triethylamine addition was measured. Since this acid value includes NMP, the acid value of the urethane prepolymer alone before the actual addition of triethylamine is 28.4 mgKOH / g as a calculated value.

  To a 5 L disposable cup, add 1501 g of water at 40 ° C., 16 g of triethylamine, and 2.7 g of SE-21, and stir with a disper for 5 minutes. Then, add 1295 g of the urethane prepolymer over 5 minutes and stir for 30 minutes. Went. Thereafter, 81.1 g of an aqueous solution of ethylenediamine / water = 1/3 (mass ratio) was added and further stirred for 30 minutes. Further, 365.7 g of an aqueous 13% zirconium ammonium carbonate solution (an amount corresponding to 5% zirconium ammonium carbonate with respect to the total mass of the polyurethane resin component and ammonium zirconium carbonate) was added, and the mixture was stirred for 10 minutes. Resin composition B-1 was obtained. Table 1 shows the evaluation of the storage stability, corrosion resistance, chemical resistance, and alkali resistance of the obtained B-1.

[Comparative Example 2]
To a five-neck separable round bottom flask equipped with a Dimroth, a stirring blade, and a nitrogen line, 145.3 g of Poly-THF1000, 132.5 g of H-MDI, 19.2 g of dimethylolpropionic acid, and 134.8 g of NMP are added. The reaction system was cooled to 60 ° C., and 14.7 g of triethylamine was added to produce an NMP-containing urethane prepolymer. It was 18 mgKOH / g when the acid value of the urethane prepolymer containing NMP before the addition of triethylamine was measured. Since this acid value includes NMP, the acid value of the urethane prepolymer alone before the actual addition of triethylamine is 27.1 mgKOH / g as a calculated value.

  To a 2 L disposable cup, add 525.6 g of 40 ° C. water, 4.4 g of triethylamine, and 1 g of SE-21. After stirring for 5 minutes with a disper, add 445.8 g of the urethane prepolymer over 5 minutes. For 30 minutes. Thereafter, 18.1 g of an aqueous solution of ethylenediamine / water = 1/3 (mass ratio) was added and further stirred for 30 minutes. Further, 124.4 g of a 13% zirconium ammonium carbonate aqueous solution (an amount corresponding to 5% zirconium ammonium carbonate with respect to the total mass of the polyurethane resin component and ammonium zirconium carbonate) was added, and the mixture was stirred for 10 minutes. Resin composition B-2 was obtained. Table 1 shows the evaluation of storage stability, corrosion resistance, chemical resistance and alkali resistance of the obtained B-2.

[Comparative Example 3]
Instead of 13% aqueous solution of ammonium ammonium carbonate, 43.4 g of V-02-L2 (in 3% amount of V-02-L2 with respect to the total mass of the polyurethane resin component and the active ingredient in V-02-L2) The amount was changed to the amount corresponding to the active ingredient), and the one-component aqueous resin composition B-3 was obtained in the same manner as in Example 1. Table 1 shows the evaluation of the storage stability, corrosion resistance, chemical resistance, and alkali resistance of the obtained B-3.

[Comparative Example 4]
A one-part aqueous resin composition B-4 was obtained in the same manner as in Example 1 except that the 13% aqueous solution of ammonium zirconium carbonate was not used. Table 1 shows the evaluation of the storage stability, corrosion resistance, chemical resistance, and alkali resistance of the obtained B-4.

As Table 1 shows, the one-component aqueous resin composition of the present invention has performances excellent in corrosion resistance, chemical resistance, and alkali resistance, and is also excellent in storage stability.

  On the other hand, in Comparative Examples 1 and 2 using a polyol other than polycarbonate diol as a raw material for the urethane prepolymer, the metal cross-linking agent contained in the one-part aqueous resin composition was stored during the storage of the one-part aqueous resin composition. Sedimented. Such a one-component water-based resin composition has poor storage stability, so it must be prepared immediately before use as a coating material and lacks workability.

  Further, in Comparative Example 3 in which the crosslinking agent added to the one-part aqueous resin composition is not the metal crosslinking agent of the present invention, and in Comparative Example 4 in which the crosslinking agent was not blended in the one-part aqueous resin composition, the corrosion resistance, Either chemical or alkali resistance is inferior. The coating film obtained from such a one-component aqueous resin composition has poor quality, and such a one-component aqueous resin composition is not suitable for paints.

  Thus, according to the present invention, long-term quality can be obtained by blending a specific stabilizer, that is, (e) a metal cross-linking agent, with a specific polyol, that is, an urethane resin aqueous dispersion using (a) polycarbonate diol as a raw material. A one-component aqueous resin composition that provides a stable and durable coating film can be produced.

  The one-part aqueous resin composition of the present invention is a resin composition having excellent workability because it is excellent in corrosion resistance, chemical resistance, and alkali resistance, and is excellent in storage stability over time. The one-part aqueous resin composition of the present invention can be widely used as a coating agent for protecting inorganic substrates such as glass, slate, concrete, and organic substrates such as wood and plastic, and is extremely useful in industry. is there.

Claims (10)

(A) a polycarbonate diol, (b) a polyisocyanate, (c) a polyurethane resin obtained by reaction of a urethane prepolymer which is a reaction product of an anionic group introducing agent and (d) a chain extender, and (e) A one-component aqueous resin composition containing a metal crosslinking agent and water. The (a) polycarbonate diol is based on one or more diols selected from 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and 2-methyl-1,3-propanediol. The one-component aqueous resin composition according to claim 1, wherein the (e) metal crosslinking agent is one or more compounds selected from zirconium-based compounds. The one-component aqueous system according to claim 1 or 2, wherein the (b) polyisocyanate is one or more compounds selected from tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and 4,4-dicyclohexylmethane diisocyanate. Resin composition. (C) The one-component aqueous resin composition according to any one of claims 1 to 3, wherein the anionic group introducing agent is one or more compounds selected from polyols containing a carboxyl group. (D) The one-component aqueous resin composition according to any one of claims 1 to 4, wherein the chain extender is one or more compounds selected from diamines, hydrazides, hydrated hydrazine, and water. The one-component aqueous system according to any one of claims 1 to 5, wherein the content of the (e) metal crosslinking agent is 0.1 to 15% by mass relative to the total amount of the polyurethane resin and (e) the metal crosslinking agent. Resin composition. The one-pack type aqueous resin composition according to any one of claims 1 to 6, wherein a change in appearance by visual observation is not observed after storage at 50 ° C for 2 weeks. The one-component aqueous resin composition according to any one of claims 1 to 7, which is used for coating. The manufacturing method of the one-pack type aqueous resin composition in any one of Claims 1-8 including the following processes 1-4.
(Step 1) (a) polycarbonate diol, (b) polyisocyanate, and (c) a step of producing a urethane prepolymer by reacting an anionic group introducing agent,
(Step 2) A step of dispersing the urethane prepolymer in water,
(Step 3) The urethane prepolymer in the aqueous dispersion is reacted with (d) a chain extender to synthesize a polyurethane resin, thereby producing an aqueous polyurethane resin composition containing the polyurethane resin at a concentration of 10 to 70% by mass. Process,
(Step 4) A step of producing a one-component aqueous resin composition by mixing the water-based polyurethane resin composition with (e) a metal crosslinking agent. A paint comprising the one-component aqueous resin composition according to claim 1.