JP6943082B2 - Aqueous polyurethane resin dispersion and its use - Google Patents

Description

The present invention relates to an aqueous polyurethane resin dispersion in which a polyurethane resin is dispersed in an aqueous medium, and more particularly to an aqueous polyurethane resin that gives a coating film having high adhesion to a substrate. The present invention also comprises a method for producing the aqueous polyurethane resin dispersion, a coating composition containing the aqueous polyurethane resin dispersion, a coating composition, an ink composition, and the polyurethane resin dispersion. The present invention relates to a polyurethane resin film obtained by drying an object.

Since the aqueous polyurethane resin dispersion is an environment-friendly material capable of reducing volatile organic compounds as compared with the conventional solvent-based urethane, it is a material that is being replaced with solvent-based polyurethane.

Since the water-based polyurethane resin dispersion has excellent adhesion to the base material, abrasion resistance, impact resistance, solvent resistance, etc., paper, plastics, etc. can be used as paints, inks, adhesives, and various coating agents. Widely used in films, metals, rubbers, elastomers, textile products, etc.
In these technical fields, it is required to lower the drying / baking temperature and shorten the heating time from the viewpoint of environmental friendliness, but in general, simplification of heat treatment reduces the adhesion of the coating film to the substrate. It is said that it will lead to weakening of mechanical properties. Therefore, an aqueous polyurethane resin that exhibits sufficient properties under low-temperature heat treatment conditions is desired.

An aqueous polyurethane resin dispersion having a urethane bond, a urea bond, and a carbonate bond and having a specific amount of blocked isocyanato groups has been found (see Patent Document 1).

Further, an organic solvent-based polyurethane resin has been found in which a nitrogen atom of a urea group is modified with a substituent having a large steric hindrance to give a coating film having high self-repairing property by a reversible bond. (Patent Document 2)

International Publication No. 2010/098316 International Publication No. 2014/144539

However, the polyurethane resin dispersion having a blocked isocyanato group has a problem that sufficient adhesion to the substrate cannot be obtained under baking conditions at a temperature lower than the dissociation temperature of the blocking agent.
Further, it has been known that a coating film having high self-repairing property can be obtained by modifying the nitrogen atom of the urea group with a substituent having a large steric hindrance, but there is no mention of substrate adhesion. , Solvent-based urethane has problems with respect to environmental pollution and toxicity to the human body.
Therefore, an object of the present invention is to obtain an aqueous polyurethane resin dispersion that gives a coating film showing high adhesion to a substrate even when baked at a relatively low temperature.

（上記式（Ａ）、式（Ｂ）、式（Ｃ）、式（Ｄ）及び式（Ｅ）中のＲ^１、Ｒ^２、Ｒ^３は、置換若しくは無置換のＣ１〜Ｃ６のアルキル基、置換若しくは無置換のＣ６〜Ｃ２０のシクロアルキル基、又は置換若しくは無置換のＣ６〜Ｃ１２のアリール基を示し、Ｒ^４、Ｒ^５、Ｒ^６は、置換若しくは無置換のＣ１〜Ｃ６のアルキル基、置換若しくは無置換のＣ６〜Ｃ２０のシクロアルキル基、置換若しくは無置換のＣ６〜Ｃ１２のアリール基、又は水素を示す。Ｒ^１〜Ｒ^６は、互いに結合して脂環式構造又は芳香環を形成してもよい。また、式（Ｂ）及び式（Ｅ）中のＣＴは、第三級炭素原子を示す。）
［７］［１］〜［６］のいずれかに記載の水性ポリウレタン樹脂分散体を含有する塗料組成物。
［８］［１］〜［６］のいずれかに記載の水性ポリウレタン樹脂分散体を含有する、コーティング剤組成物。
［９］［１］〜［６］のいずれかに記載の水性ポリウレタン樹脂分散体を含有する、インク組成物。
［１０］［１］〜［６］のいずれかに記載の水性ポリウレタン樹脂分散体を含む組成物を乾燥及び硬化させて得られるポリウレタン樹脂フィルム。 The present invention is an invention made in order to solve the above-mentioned problems, and specifically has the following configuration.
[1] A polyurethane resin composed of (A) a polyurethane prepolymer having at least one isocyanato group and (B) a chain extender having two or more amino groups or imino groups in one molecule is contained in an aqueous medium. A dispersed aqueous polyurethane resin dispersion
(B) An aqueous polyurethane resin dispersion in which the chain extender contains a compound having at least one tertiary carbon atom on the nitrogen atom of at least one amino group or imino group.
[2] The description in [1], wherein the (A) polyurethane prepolymer has (a) a structure derived from a polyisocyanate compound, (b) a structure derived from a polyol compound, and (c) a structure derived from an acidic group-containing polyol compound. Aqueous polyurethane resin dispersion.
[3] The polyurethane prepolymer (A) further has a structure derived from (d) hydroxyalkanoic acid and / or (e) a structure derived from an isocyanato group blocking agent that dissociates at 80 ° C to 180 ° C. The aqueous polyurethane resin dispersion according to [2].
[4] The aqueous polyurethane resin dispersion according to [2] or [3], wherein the polyol compound (b) is a polycarbonate polyol.
[5] The content of the tertiary carbon atom on the nitrogen atom of the amino group or imino group of the chain extender (B) is 0.1% by weight or more based on the solid content in the aqueous polyurethane resin dispersion. The aqueous polyurethane resin dispersion according to any one of [1] to [4].
[6] The compound having at least one tertiary carbon atom on the nitrogen atom of the at least one amino group or imino group is the following formula (A), formula (B), formula (C), formula (D). ) And the aqueous polyurethane resin dispersion according to any one of [1] to [5], which is a compound having at least one structure represented by the formula (E).

(The above formula (A), Formula ^{(B), R 1, R} 2, R 3 in the formula (C), formula (D) and Formula (E) is a substituted or unsubstituted C1~C6 alkyl group, Substituentally substituted or unsubstituted C6-C20 cycloalkyl groups or substituted or unsubstituted C6-C12 aryl groups are indicated, and R ⁴ , R ⁵ , and R ⁶ are substituted or unsubstituted C1 to C6 alkyl groups. Indicates a substituted or unsubstituted C6-C20 cycloalkyl group, a substituted or unsubstituted C6-C12 aryl group, or hydrogen. R ^{1 to} R ⁶ are bonded to each other to form an alicyclic structure or an aromatic ring. Also, CT in formula (B) and formula (E) indicates a tertiary carbon atom.)
[7] A coating composition containing the aqueous polyurethane resin dispersion according to any one of [1] to [6].
[8] A coating agent composition containing the aqueous polyurethane resin dispersion according to any one of [1] to [6].
[9] An ink composition containing the aqueous polyurethane resin dispersion according to any one of [1] to [6].
[10] A polyurethane resin film obtained by drying and curing a composition containing the aqueous polyurethane resin dispersion according to any one of [1] to [6].

INDUSTRIAL APPLICABILITY The present invention provides an aqueous polyurethane resin dispersion having high adhesion to a substrate even when baked at a relatively low temperature.

<< Polyurethane resin >>
The aqueous polyurethane resin dispersion of the present invention is composed of (A) a polyurethane prepolymer having at least one isocyanato group and (B) a chain extender having two or more amino groups or imino groups in one molecule. An aqueous polyurethane resin dispersion in which a polyurethane resin is dispersed in an aqueous medium, wherein the chain extender (B) has at least one tertiary carbon atom on the nitrogen atom of at least one amino group or imino group. Includes compounds with.
The (A) polyurethane prepolymer is preferably obtained by reacting (a) a polyisocyanate compound, (b) a polyol compound and (c) an acidic group-containing polyol compound, and (a) a polyisocyanate compound, (b). It is obtained by reacting a polyol compound, (c) an acidic group-containing polyol compound, and (d) hydroxyalkanoic acid, and / or (e) a blocking agent for an isocyanate group that dissociates at 80 ° C to 180 ° C. Is more preferable.
Therefore, it is preferable that (A) the polyurethane prepolymer has (a) a structure derived from a polyisocyanate compound, (b) a structure derived from a polyol compound, and (c) a structure derived from an acidic group-containing polyol compound. d) It is more preferable to have a structure derived from hydroxyalkanoic acid and / or (e) a structure derived from an isocyanate group blocking agent that dissociates at 80 ° C to 180 ° C.

<< (a) Polyisocyanate compound >>
The polyisocyanate compound (a) is not particularly limited, and examples thereof include aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.

Examples of the aromatic polyisocyanate include 1,3-phenylenediocyanate, 1,4-phenylenediocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, and 4,4'-diphenylmethane diisocyanate ( MDI), 2,4-diphenylmethane diisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-di Examples thereof include isocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, 4,4', 4''-triphenylmethane triisocyanate, m-isocyanatophenylsulfonylisocyanate, and p-isocyanatophenylsulfonylisocyanate.

Examples of the aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecantryisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate. , 2,6-Diisocyanatomethyl caproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate. Be done.

Examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), and bis (2-isocyanato). Ethyl) -4-cyclohexene-1,2-dicarboxylate, 2,5-norbornan diisocyanate, 2,6-norbornan diisocyanate can be mentioned.

As the polyisocyanate compound, one having two isocyanato groups per molecule can be used, but (A) per molecule such as triphenylmethane triisocyanate as long as the polyurethane prepolymer does not gel. Polyisocyanate compounds having three or more isocyanato groups can also be used.

Among the polyisocyanate compounds, isophorone diisocyanate (IPDI) and 4,4'-dicyclohexylmethane diisocyanate (hydrogenated) are preferable because the durability of the coating film is improved and the alicyclic polyisocyanate is preferable and the reaction can be easily controlled. MDI) is particularly preferred.

The polyisocyanate may be used alone or in combination of two or more.

<< (b) polyol compound >>
(B) As the polyol compound, a high molecular weight polyol or a low molecular weight polyol can be used. The type of the polyol compound is not particularly limited as long as it has two or more hydroxyl groups in one molecule. The polyol compound (b) is a polyol compound other than the (c) acidic group-containing polyol compound described later.

The high molecular weight polyol is not particularly limited, but preferably has a number average molecular weight of 400 to 8,000. When the number average molecular weight is in this range, appropriate viscosity and good handleability can be obtained. In addition, it is easy to secure the performance as a soft segment. Further, the reactivity of (a) the polyisocyanate compound and (b) the polyol compound becomes sufficient, and (a) the polyisocyanate compound is reacted with (b) the polyol compound and (c) the acidic group-containing polyol compound. The resulting polyurethane prepolymer (A) can also be efficiently produced. The high molecular weight polyol preferably has a number average molecular weight of 400 to 4,000.

In the present specification, the number average molecular weight is the number average molecular weight calculated based on the hydroxyl value measured according to JIS K 1577. Specifically, the hydroxyl value is measured and calculated by the terminal group quantification method as (56.1 × 1,000 × valence) / hydroxyl value [mgKOH / g]. In the above formula, the valence is the number of hydroxyl groups in one molecule.

Examples of high-molecular-weight polyols include polycarbonate polyols, polyester polyols, and polyether polyols. A polycarbonate polyol is preferable from the viewpoint of light resistance, weather resistance, heat resistance, hydrolysis resistance, and oil resistance of the aqueous resin dispersion containing the polyurethane resin and the coating film obtained from the aqueous resin dispersion. Further, a polyether polyol is preferable from the viewpoint of more excellent adhesion of the obtained coating film.

Polycarbonate polyol is obtained by reacting one or more kinds of polyol monomers with a carbonic acid ester or phosgene. A polycarbonate polyol obtained by reacting one or more kinds of polyol monomers with a carbonic acid ester is preferable because it is easy to produce and there is no by-production of terminal chlorinated products.
The polycarbonate polyol referred to in the present invention may contain as many ether bonds and ester bonds as the average number of carbonate bonds in one molecule or less.

The polyol monomer is not particularly limited, and examples thereof include an aliphatic polyol monomer, a polyol monomer having an alicyclic structure, an aromatic polyol monomer, a polyester polyol monomer, and a polyether polyol monomer.

The aliphatic polyol monomer is not particularly limited, but for example, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1 , 8-octanediol, 1,9-nonanediol and other linear aliphatic diols; 2-methyl-1,3-propanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5 Branched chain aliphatic diols such as -pentanediol and 2-methyl-1,9-nonanediol; trifunctional and higher functional alcohols such as trimethylolpropane and pentaerythritol can be mentioned.

The polyol monomer having an alicyclic structure is not particularly limited, and for example, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclopentanediol, 1, Examples thereof include diols having an alicyclic structure in the main chain such as 4-cycloheptandiol, 2,7-norbornandiol, and 1,4-bis (hydroxyethoxy) cyclohexane.

The aromatic polyol monomer is not particularly limited, and is, for example, 1,4-benzenedimethanol, 1,3-benzenedimethanol, 1,2-benzenedimethanol, 4,4'-naphthalenemethanol, 3,4. '-Naphthalene methanol is mentioned.

The polyester polyol monomer is not particularly limited, and is, for example, a polyester polyol of hydroxycarboxylic acid and diol such as a polyester polyol of 6-hydroxycaproic acid and hexanediol, and a dicarboxylic acid such as a polyester polyol of adipic acid and hexanediol. And polyester polyol with diol.

The polyether polyol monomer is not particularly limited, and examples thereof include polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

The carbonic acid ester is not particularly limited, and examples thereof include an aliphatic carbonic acid ester such as dimethyl carbonate and diethyl carbonate, an aromatic carbonic acid ester such as diphenyl carbonate, and a cyclic carbonic acid ester such as ethylene carbonate. In addition, phosgene or the like capable of producing a polycarbonate polyol can also be used. Of these, aliphatic carbonic acid esters are preferable, and dimethyl carbonate is particularly preferable, from the viewpoint of ease of production of polycarbonate polyol.

As a method for producing a polycarbonate polyol from a polyol monomer and a carbonic acid ester, for example, a carbonic acid ester and a polyol monomer having an excessive number of moles with respect to the number of moles of the carbonic acid ester are added to the reactor, and the temperature is 160 to 200 ° C. A method of reacting at a pressure of about 50 mmHg for 5 to 6 hours and then further reacting at a pressure of several mmHg or less at 200 to 220 ° C. for several hours can be mentioned. In the above reaction, it is preferable to carry out the reaction while extracting the alcohol produced as a by-product from the system. At that time, if the carbonic acid ester escapes from the system by azeotropically boiling with the alcohol produced as a by-product, an excessive amount of the carbonic acid ester may be added. Further, in the above reaction, a catalyst such as titanium tetrabutoxide may be used.

Further, as the high molecular weight polyol, it is preferable to use a high molecular weight diol because of the ease of production of the aqueous polyurethane resin dispersion. Examples of the high molecular weight diol include polycarbonate diol, polyester diol, and polyether diol. Polycarbonate diol is preferable from the viewpoint of light resistance, weather resistance, heat resistance, hydrolysis resistance, and oil resistance of the aqueous resin dispersion containing the polyurethane resin and the coating film obtained from the aqueous resin dispersion. A polyether diol is preferable because the adhesion of the obtained coating film is higher.

Among the polycarbonate diols, the diol component is preferably an aliphatic diol and / or an alicyclic diol, and the obtained (A) polyurethane prepolymer has a low viscosity, is easy to handle, and has dispersibility in an aqueous medium. It is more preferable that the diol component is an aliphatic diol having no alicyclic structure, because the diol component is good and the drying property at the time of forming a coating film is high.

The polycarbonate diol is not particularly limited, but for example, a polycarbonate diol obtained by reacting 1,6-hexanediol with a carbonic acid ester, a mixture of 1,6-hexanediol and 1,5-pentanediol and a carbonic acid ester. Polycarbonate diol obtained by reacting with, 1,6-hexanediol and 1,4-butanediol mixture with carbonic acid ester, polycarbonate diol obtained by reacting 1,4-cyclohexanedimethanol and carbonic acid ester Examples thereof include a polycarbonate diol obtained by reacting with and a polycarbonate diol obtained by reacting a mixture of 1,6-hexanediol and 1,4-cyclohexanedimethanol with a carbonic acid ester.

The polyester diol is not particularly limited, and for example, polyethylene adipate diol, polybutylene adipate diol, polyethylene butylene adipate diol, polyhexamethylene isophthalate adipate diol, polyethylene succinate diol, polybutylene succinate diol, and polyethylene sevacate diol. , Polybutylene succirate diol, poly-ε-caprolactone diol, poly (3-methyl-1,5-pentylene adipate) diol, polycondensate of 1,6-hexanediol and dimer acid and the like.

The polyether diol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene oxide and propylene oxide, random copolymers of ethylene oxide and butylene oxide, and block copolymers. Further, a polyether polyester polyol having an ether bond and an ester bond may be used.

As the low molecular weight polyol, a low molecular weight diol can also be used because of the ease of production of the aqueous polyurethane resin dispersion. The low molecular weight diol is not particularly limited, and examples thereof include those having a number average molecular weight of 60 or more and less than 400. Examples of low molecular weight diols include ethylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, and 2-butyl-2-ethyl-. 1,3-Propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, 2-methyl- An aliphatic diol having 2 to 9 carbon atoms such as 1,8-octanediol, diethylene glycol, triethylene glycol, tetraethylene glycol; 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol , 1,4-Bis (hydroxyethyl) cyclohexane, 2,7-norbornanediol, tetrahydrofurandimethanol, 2,5-bis (hydroxymethyl) -1,4-dioxane, etc. Examples thereof include diols having. Further, as the low molecular weight polyol, a low molecular weight polyhydric alcohol such as trimethylolpropane, pentaerythritol, or sorbitol can also be used.

(B) As the polyol compound, one type may be used alone, or a plurality of types may be used in combination.

<< (c) Acid group-containing polyol compound >>
(C) The acidic group-containing polyol compound contains two or more hydroxyl groups (excluding phenolic hydroxyl groups) and one or more acidic groups in one molecule. Examples of the acidic group include a carboxy group, a sulfonic acid group, a phosphoric acid group, a phenolic hydroxyl group and the like. (C) As the acidic group-containing polyol compound, a compound having two hydroxyl groups and one carboxy group in one molecule is preferable.

(C) The acidic group-containing polyol compound is not particularly limited, and is, for example, dimethylol alkanoic acid such as 2,2-dimethylol propionic acid and 2,2-dimethylol butanoic acid, and N, N-bishydroxyethylglycine. , N, N-bishydroxyethylalanine, 3,4-dihydroxybutanesulfonic acid, 3,6-dihydroxy-2-toluenesulfonic acid. Of these, dimethylolalkanoic acid having 4 to 12 carbon atoms containing two methylol groups is preferable from the viewpoint of easy availability. Among the dimethylolalkanoic acids, 2,2-dimethylolpropionic acid is more preferable. (C) As the acidic group-containing polyol compound, one type may be used alone, or a plurality of types may be used in combination.

In the present invention, the total number of hydroxyl group equivalents of (b) the polyol compound and (c) the acidic group-containing polyol compound is preferably 120 to 1,000. When the number of hydroxyl group equivalents is within this range, the drying property and the thickening property are likely to increase, the aqueous resin dispersion containing the obtained polyurethane resin is easily produced, and a coating film having excellent hardness is easily obtained. .. From the viewpoint of storage stability and drying property of the obtained aqueous polyurethane resin dispersion and hardness of the coating film obtained by coating, the number of hydroxyl group equivalents is preferably 200 to 1,000, more preferably 400 to 800, and particularly preferably. Is 600-700.

The total number of hydroxyl group equivalents of the polyol compound (b) and the acidic group-containing polyol compound (c) can be calculated by the following formulas (1) and (2).
Equivalent number of hydroxyl groups of each polyol compound = Molecular weight of each polyol compound / Number of hydroxyl groups of each polyol compound (excluding phenolic hydroxyl groups) ... (1)
Total number of hydroxyl group equivalents of polyol compounds ((b), (c)) = total number of moles of M / polyol compounds ((b), (c)) ... (2)
In the case of a polyurethane resin, in the formula (2), M is [[(b) number of hydroxyl equivalents of the polyol compound × (b) number of moles of the polyol compound] + [(c) number of hydroxyl equivalents of the acidic group-containing polyol compound × (C) Number of moles of acidic group-containing polyol compound]].

<< (d) hydroxyalkanoic acid >>
(D) As the hydroxyalkanoic acid, a compound having one carboxyl group and one hydroxyl group in one molecule can be used. (D) The number of carbon atoms of the hydroxyalkanoic acid is preferably 2 to 30, more preferably 6 to 30, and particularly preferably 10 to 26. (D) When the number of carbon atoms of the hydroxyalkanoic acid is 2 to 30, the water swelling rate of the obtained polyurethane film tends to be low, and the adhesion to the electrodeposited surface tends to be high. (D) The hydroxyalkanoic acid is glycolic acid (2-hydroxyacetic acid), 3-hydroxybutyric acid, 4-hydroxybutyric acid, 10-hydroxydecanoic acid, hydroxypivalic acid (2,2-dimethyl-3-hydroxypropionic acid). , 12-Hydroxydodecanic acid, 16-hydroxyhexadecanoic acid, lactic acid, trichlorolactic acid, salicylic acid, hydroxybenzoic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxypropionic acid, 2-hydroxyoctanoic acid, 3-hydroxyundecanoic acid , 12-Hydroxystearic acid, 12-hydroxyoleic acid and the like, and glycolic acid, 4-hydroxybutyric acid, hydroxypivalic acid, 12-hydroxystearic acid and the like are preferable. 12-Hydroxystearic acid is particularly preferable as the (d) hydroxyalkanoic acid from the viewpoint that the water swelling rate of the obtained polyurethane film becomes lower. (D) One type of hydroxyalkanoic acid may be used alone, or a plurality of types may be used in combination.

<< (e) Isocyanato group blocking agent that dissociates at 80 to 180 ° C >>
As the blocking agent for the isocyanato group (hereinafter, also referred to as “(e) blocking agent”) that dissociates at 80 to 180 ° C., a compound that dissociates from the isocyanato group at 80 to 180 ° C. can be used. The "blocking agent" means a compound capable of reacting with an isocyanato group to convert an isocyanato group into another group, which can be reversibly converted from another group to an isocyanato group by heat treatment. (E) The blocking agent is a malonate ester compound, preferably a malonate diester compound such as dimethyl malonate or diethyl malonate; a pyrazole compound such as 1,2-pyrazole or 3,5-dimethylpyrazole; 1 , 2,4-Triazole, 1,2,3-triazole and other triazole compounds, methyl ethyl ketooxime and other oxime compounds; diisopropylamine, caprolactam and the like. The blocking agent (e) is preferably one or more selected from the group consisting of oxime compounds, pyrazole compounds and malonic acid ester compounds from the viewpoint of dissociation temperature. As the blocking agent (e), a pyrazole-based compound is more preferable, and 3,5-dimethylpyrazole is particularly preferable, from the viewpoint of high storage stability and low-temperature thermal cross-linking property. (E) One type of blocking agent may be used alone, or a plurality of types may be used in combination.

<< (A) Polyurethane Prepolymer >>
The (A) polyurethane prepolymer is preferably a polyurethane prepolymer obtained by reacting (a) a polyisocyanate compound, (b) a polyol compound, and (c) an acidic group-containing polyol compound, and (a) to (a) to It is more preferable to obtain a polyurethane prepolymer by further reacting (d) hydroxyalkanoic acid and / or (e) an isocyanate group-blocking agent that dissociates at 80 to 180 ° C. in addition to the component (c). Therefore, it is preferable that (A) the polyurethane prepolymer has (a) a structure derived from a polyisocyanate compound, (b) a structure derived from a polyol compound, and (c) a structure derived from an acidic group-containing polyol compound. d) It is more preferable to have a structure derived from hydroxyalkanoic acid and / or (e) a structure derived from an isocyanate group blocking agent that dissociates at 80 ° C to 180 ° C.
The method for producing the polyurethane prepolymer is not particularly limited, and examples thereof include the following methods.

The first method is to use (a) a polyisocyanate compound, (b) a polyol compound, (c) an acidic group-containing polyol compound, and any (d) hydroxyalkanoic acid in the presence or absence of a urethanization catalyst. And an arbitrary (e) blocking agent are mixed at the same time to synthesize (A) a polyurethane prepolymer via a urethanization reaction.

In the second method, the urethanization reaction is carried out by reacting (a) a polyisocyanate compound, (b) a polyol compound, and (c) an acidic group-containing polyol compound in the presence or absence of a urethanization catalyst. After that, any (d) hydroxyalkanoic acid is reacted with any (e) blocking agent to synthesize (A) a polyurethane prepolymer.

In the third method, the urethanization reaction is carried out by reacting (a) a polyisocyanate compound, (b) a polyol compound, and (c) an acidic group-containing polyol compound in the presence or absence of a urethanization catalyst. After that, (d) hydroxyalkanoic acid is reacted, and finally (e) a blocking agent is reacted in the presence or absence of a blocking catalyst to carry out a blocking reaction, and a part of the terminal isocyanato group is blocked. (A) A method for synthesizing a polyurethane prepolymer.

In the fourth method, in the presence or absence of a blocking catalyst, (a) a polyisocyanate compound and (e) a blocking agent are reacted to carry out a blocking reaction to block a part of isocyanato groups. The polyisocyanate compound was synthesized, and in the presence or absence of a urethanization catalyst, (b) a polyol compound and (c) an acidic group-containing polyol compound were reacted to carry out a urethanization reaction, and finally ( d) A method for synthesizing (A) a polyurethane prepolymer by reacting with hydroxyalkanoic acid.

The urethanization catalyst is not particularly limited, and is a metal such as a tin catalyst (trimethyltin laurate, dibutyltin dilaurate, etc.), a lead catalyst (lead octylate, etc.), an organic and inorganic acid salt, an organic metal derivative, and an amine. Examples thereof include system catalysts (triethylamine, N-ethylmorpholin, triethylenediamine, etc.), diazabicycloundecene-based catalysts, and the like. The urethanization catalyst is preferably dibutyltin dilaurate from the viewpoint of reactivity. The blocking catalyst is not particularly limited, and examples thereof include metals such as dibutyltin dilaurate, salts of organic and inorganic acids, and alkaline catalysts such as sodium methoxyde. The conditions for the urethanization reaction and the conditions for the blocking reaction are not particularly limited and can be appropriately selected depending on the reactivity of the components to be used and the like. For example, the conditions for the urethanization reaction can be 3 to 15 hours at a temperature of 50 to 100 ° C. The conditions for the blocking reaction can be 1 to 5 hours at a temperature of 50 to 100 ° C. The urethanization reaction and the blocking reaction may be carried out independently or continuously.

(A) The polyurethane prepolymer has at least one isocyanato group. The amounts of (a), (b), (c), (d) and (e) used are selected to contain free isocyanato groups, preferably containing 0.5 to 5. free isocyanato groups. It is 0%, the total of the urethane bond content and the urea bond content is 7 to 18% by weight based on the solid content, and the carbonate bond content is 0% by weight or more and less than 30% by weight based on the solid content. The content ratio of the alicyclic structure is 5 to 40% by weight based on the solid content, and the content ratio of the isocyanato group to which the blocking agent is bound is 0.1 to 3.0% by weight based on the solid content and the isocyanato group. The amount used is preferably selected within the above range.

In the present invention, the acid value (AV) of the polyurethane prepolymer is preferably 4 to 40 mgKOH / g, more preferably 6 to 32 mgKOH / g, and particularly preferably 8 to 29 mgKOH / g. By setting the acid value of the polyurethane prepolymer to 4 mgKOH / g or more, the dispersibility in an aqueous medium and the storage stability tend to be improved. Further, by setting the acid value of the polyurethane prepolymer to 40 mgKOH / g or less, the water resistance of the coating film of the obtained polyurethane resin tends to be increased, and the flexibility of the obtained film tends to be increased. In addition, there is a tendency that the drying property at the time of producing a coating film can be improved.
In the present invention, the "acid value of the polyurethane prepolymer" is the so-called solid content excluding the solvent used in producing the polyurethane prepolymer and the neutralizing agent for dispersing the polyurethane prepolymer in the aqueous medium. The acid value inside.
Specifically, the acid value of the polyurethane prepolymer can be derived by the following formula (3).
[Acid value of polyurethane prepolymer] = [((c) Number of mmol of acidic group-containing polyol compound) × ((c) Number of acidic groups in one molecule of acidic group-containing polyol compound) + ((d) Hydroxyalkanoic acid (The number of mmol of) × ((d) number of acidic groups in one molecule of hydroxyalkanoic acid)] × 56.11 / [(a) polyisocyanate compound, (c) acidic group-containing polyol compound, (d) hydroxyalkanoic acid , (E) Blocking agent, and (b) Total mass of polyol compound] ... (3)

（上記式（Ａ）、式（Ｂ）、式（Ｃ）、式（Ｄ）及び式（Ｅ）中のＲ^１、Ｒ^２、Ｒ^３は、置換若しくは無置換のＣ１〜Ｃ６のアルキル基、置換若しくは無置換のＣ６〜Ｃ２０のシクロアルキル基、又は置換若しくは無置換のＣ６〜Ｃ１２のアリール基を示し、Ｒ^４、Ｒ^５、Ｒ^６は、置換若しくは無置換のＣ１〜Ｃ６のアルキル基、置換若しくは無置換のＣ６〜Ｃ２０のシクロアルキル基、置換若しくは無置換のＣ６〜Ｃ１２のアリール基又は水素を示す。Ｒ^１〜Ｒ^６は、互いに結合して脂環式構造又は芳香環を形成してもよい。また、式（Ｂ）及び式（Ｅ）中のＣＴは、第三級炭素原子を示す。）
前記少なくとも１つのアミノ基又はイミノ基の窒素原子上に少なくとも１つの第三級炭素原子を有する化合物としては、Ｎ，Ｎ’−ジ−ｔ−ブチルエチレンジアミン、（１Ｒ，２Ｒ）‐Ｎ，Ｎ′‐ジｔｅｒｔ‐ブチル‐１，２‐ビス（２‐ナフチル）エチレンジアミン、Ｎ’−シクロヘキシル−２−メチル−Ｎ−（２−メチルプロピル）−２，４−ペンタンジアミン、１，２−ビス（２−アミノ−２−プロピル）ベンゼン、１，３−ビス（２−アミノ−２−プロピル）ベンゼン、１，４−ビス（２−アミノ−２−プロピル）ベンゼン等が挙げられる。樹脂分散体の焼付後の密着性、焼付後の塗膜弾性率の制御のしやすさ、イソシアナト基の反応性などの点から、（Ｂ）鎖延長剤はＮ，Ｎ’−ジ−ｔ−ブチルエチレンジアミン、１，２−ビス（２−アミノ−２−プロピル）ベンゼン、１，３−ビス（２−アミノ−２−プロピル）ベンゼン、１，４−ビス（２−アミノ−２−プロピル）ベンゼンが特に好ましい。 << (B) Chain extender >>
(B) The chain extender has two or more amino groups or imino groups in one molecule. Then, it contains a compound having at least one tertiary carbon atom on the nitrogen atom of at least one amino group or imino group. Tertiary carbon refers to carbon to which three carbon atoms are bonded.
Specific examples of a compound having two or more amino groups or imino groups in one molecule and having at least one tertiary carbon atom on the nitrogen atom of at least one amino group or imino group include, for example, , An amine compound or an imine compound having at least one structure represented by the following formulas (A), formula (B), formula (C), formula (D) and formula (E).

(The above formula (A), Formula ^{(B), R 1, R} 2, R 3 in the formula (C), formula (D) and Formula (E) is a substituted or unsubstituted C1~C6 alkyl group, Substituentally substituted or unsubstituted C6-C20 cycloalkyl groups or substituted or unsubstituted C6-C12 aryl groups are indicated, and R ⁴ , R ⁵ , and R ⁶ are substituted or unsubstituted C1 to C6 alkyl groups. It represents a substituted or unsubstituted C6-C20 cycloalkyl group, a substituted or unsubstituted C6-C12 aryl group or hydrogen. R ^{1 to} R ⁶ are bonded to each other to form an alicyclic structure or an aromatic ring. Also, CT in formula (B) and formula (E) indicates a tertiary carbon atom.)
Examples of the compound having at least one tertiary carbon atom on the nitrogen atom of the at least one amino group or imino group include N, N'-di-t-butylethylenediamine, (1R, 2R) -N, N'. -Ditert-Butyl-1,2-bis (2-naphthyl) ethylenediamine, N'-cyclohexyl-2-methyl-N- (2-methylpropyl) -2,4-pentanediamine, 1,2-bis (2) Examples thereof include −amino-2-propyl) benzene, 1,3-bis (2-amino-2-propyl) benzene, and 1,4-bis (2-amino-2-propyl) benzene. The chain extender (B) is N, N'-di-t- from the viewpoints of adhesion after baking of the resin dispersion, ease of controlling the elasticity of the coating film after baking, and reactivity of isocyanato groups. Butylethylenediamine, 1,2-bis (2-amino-2-propyl) benzene, 1,3-bis (2-amino-2-propyl) benzene, 1,4-bis (2-amino-2-propyl) benzene Is particularly preferable.

The compound having at least one tertiary carbon atom on the nitrogen atom of the at least one amino group or imino group is a compound having one or more amino groups or imino groups and one or more hydroxyl groups in one molecule. including. For example, Nt-butylethanolamine can be mentioned.

By using a compound having at least one tertiary carbon atom on the nitrogen atom of the amino group or the imino group as the chain extender (B), the polyurethane resin dispersion is baked at a relatively low temperature of 90 ° C. However, high adhesion can be obtained.

(B) The chain extender may contain other compounds in addition to the compound having at least one tertiary carbon atom on the nitrogen atom of at least one amino group or imino group.
Examples of other compounds include compounds that are reactive with the isocyanato group. For example, ethylenediamine, 1,4-tetramethylenediamine, 2-methyl-1,5-pentanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, 1,4-hexamethylenediamine, 3-aminomethyl Amines such as -3,5,5-trimethylcyclohexylamine, 1,3-bis (aminomethyl) cyclohexane, xylylenediamine, piperazin, adipoil hydrazide, hydrazine, 2,5-dimethylpiperazine, diethylenetriamine, triethylenetetramine, etc. Examples thereof include compounds, diol compounds such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol, polyalkylene glycols typified by polyethylene glycol, and water.
(B) As the chain extender, one type may be used alone, or a plurality of types may be used in combination.

The amount of the (B) chain extender added is preferably less than or equal to the equivalent of the isocyanato group which is the starting point of the chain extension in the obtained (A) polyurethane prepolymer, and more preferably 0.7 to 0.99 of the isocyanato group. Equivalent. By adding the (B) chain extender in an amount equal to or less than the equivalent of the isocyanato group, the molecular weight of the chain-extended urethane polymer was not reduced, and the obtained aqueous polyurethane resin dispersion was applied to obtain a coating film. There is a tendency for the strength to be increased. The (B) chain extender may be added after the (A) polyurethane prepolymer has been dispersed in water, or may be added during the dispersion. Chain extension can also be done with water. In this case, water as a dispersion medium also serves as a chain extender.

<< Aqueous medium >>

The polyurethane resin dispersion of the present invention contains a polyurethane resin and an aqueous medium. Examples of the aqueous medium include water, a mixture of water and an organic solvent, and the like.
Examples of the water include clean water, ion-exchanged water, distilled water, ultrapure water and the like. Above all, it is preferable to use ion-exchanged water in consideration of easy availability and unstable particles due to the influence of salt. Examples of the organic solvent include alcohol solvents such as methanol, ethanol, n-propanol and isopropanol; ketone solvents such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; and alkyl ethers of polyalkylene glycol. Solvent; Examples thereof include a lactam solvent such as N-methyl-2-pyrrolidone.
The aqueous medium is preferably contained in the range of 10% by mass to 90% by mass, more preferably in the range of 20% by mass to 80% by mass, in the total amount of the aqueous polyurethane resin dispersion of the present invention.

The polyurethane resin dispersion of the present invention contains the polyurethane resin and the aqueous medium, and the polyurethane resin is dispersed in the aqueous medium, that is, an aqueous polyurethane resin dispersion.

<< Manufacturing method of aqueous polyurethane resin dispersion >>
Next, a method for producing the aqueous polyurethane resin dispersion will be described. The method for producing the aqueous polyurethane resin dispersion is
The step (α) of reacting the (a) polyisocyanate compound, (b) polyol compound, and (c) acidic group-containing polyol compound to obtain (A) polyurethane prepolymer.
(A) Step of neutralizing the acidic group of the polyurethane prepolymer (β),
(A) Step of dispersing the polyurethane prepolymer in an aqueous medium (γ),
The step (δ) of reacting the (A) polyurethane prepolymer with the (B) chain extender having reactivity with the isocyanato group of the (A) polyurethane prepolymer is included.

The step (α) for obtaining the polyurethane prepolymer (A) may be carried out in an inert gas atmosphere or in an air atmosphere. (A) The method for preparing the polyurethane prepolymer is as described above.

As the neutralizing agent that can be used in the step (β) of neutralizing the acidic group of the polyurethane prepolymer (A), a base known to those skilled in the art can be used without particular limitation. Examples of the neutralizing agent include trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-phenyldiethanolamine, dimethylethanolamine, diethylethanolamine, and N-methylmorpholine. , Organic amines such as pyridine; inorganic alkali salts such as sodium hydroxide and potassium hydroxide, and ammonia. Among them, organic amines can be preferably used, and tertiary amines can be used more preferably. Triethylamine is more preferable because it improves dispersion stability. Here, the acidic group of (A) polyurethane prepolymer means a carboxy group, a sulfonic acid group, a phosphoric acid group, a phenolic hydroxyl group and the like.

In the step (γ) of dispersing the polyurethane prepolymer in the aqueous medium (A), the method of dispersing the polyurethane prepolymer in the aqueous medium is not particularly limited, but is agitated by, for example, a homomixer or a homogenizer. There are a method of adding (A) a polyurethane prepolymer to an aqueous medium, a method of adding an aqueous medium to (A) a polyurethane prepolymer that has been stirred by a homomixer, a homogenizer, or the like.

In the step (δ) of reacting the (A) polyurethane prepolymer with the (B) chain extender having reactivity with the isocyanato group of the (A) polyurethane prepolymer, the step (δ) is slowly performed under cooling. In some cases, the reaction may be promoted under heating conditions of 60 ° C. or lower. The reaction time under cooling can be, for example, 0.5 to 24 hours, and the reaction time under heating conditions of 60 ° C. or lower can be, for example, 0.1 to 6 hours.

In the production of the aqueous polyurethane resin dispersion, either the step (β) or the step (δ) may be performed first, or may be performed at the same time. The step (β) and the step (δ) may be performed at the same time. Further, the step (β), the step (γ), and the step (δ) may be performed at the same time.

<< Aqueous polyurethane resin dispersion >>
The proportion of the polyurethane resin in the aqueous polyurethane resin dispersion is preferably 5 to 60% by mass, more preferably 15 to 50% by mass.

The weight average molecular weight of the polyurethane resin in the aqueous polyurethane resin dispersion is usually about 25,000 to 1,000,000. More preferably, it is 50,000 to 5,000,000, and even more preferably 100,000 to 1,000,000. The weight average molecular weight is measured by gel permeation chromatography (GPC), and a converted value obtained from a calibration curve of standard polystyrene prepared in advance can be used. By setting the weight average molecular weight to 25,000 or more, a good film tends to be obtained by drying the aqueous polyurethane resin dispersion. By setting the weight average molecular weight to 1,000,000 or less, the drying property of the aqueous polyurethane resin dispersion tends to be higher.
In the aqueous polyurethane resin dispersion of the present invention, the total of urethane bonds and urea bonds in the aqueous polyurethane resin dispersion is preferably 7 to 18% by weight, particularly preferably 8 to 15% by weight, based on the solid content. ..
By setting the total content ratio of the urethane bond and the urea bond to 7% by weight or more, the stickiness of the coating film surface after the coating film is dried may be reduced. Further, by setting the total content ratio of the urethane bond and the urea bond to 18% by weight or less, the adhesion between the coating film formed from the aqueous polyurethane resin dispersion and the base material may be improved.

The total content of urethane bond and urea bond is (a) polyisocyanate compound, (b) polyol compound, (c) acidic group-containing polyol compound, (d) hydroxyalkanoic acid, (e) blocking agent and (B). ) The molecular weight of each chain extender can be controlled by the number of hydroxyl groups, isocyanate groups, and amino groups in one molecule and the ratio of each raw material used in the aqueous polyurethane resin dispersion based on the solid content.

From the viewpoint of adhesion between the coating film formed from the aqueous polyurethane resin dispersion of the present invention and the base material, the content ratio of the carbonate bond in the aqueous polyurethane resin dispersion is 0% by mass or more and 30% by weight based on the solid content. It is preferably less than%, more preferably 0% by weight or more and less than 15% by weight, and particularly preferably 0% by weight or more and less than 5% by weight.

In the aqueous polyurethane resin dispersion of the present invention, the content ratio of the isocyanato group blocked by the blocking agent is preferably 0 to 5.0% by weight based on the solid content and in terms of the isocyanato group, 0.2. It is more preferably ~ 3.0% by weight, and particularly preferably 0.5 to 2.0% by weight.
By setting the content ratio of the blocked isocyanato group to 0.2% by mass or more, the adhesion of the obtained coating film to the surface of the electrodeposited coating plate tends to increase. Further, by setting the content ratio of the blocked isocyanato group to 3.0% by weight or less, the elongation at break point of the obtained coating film tends to increase.

The acid value of the aqueous polyurethane resin dispersion is not particularly limited, but is preferably 10 to 40 mgKOH / g, more preferably 15 to 32 mgKOH / g, and 15 to 25 mgKOH / g based on the solid content. Is particularly preferred. When the acid value of the aqueous polyurethane resin dispersion is in the range of 10 to 40 mgKOH / g based on the solid content, the storage stability tends to be improved. The acid value can be measured according to the indicator titration method of JIS K 1557. In the measurement, the neutralizing agent used to neutralize the acidic group shall be removed before the measurement. For example, when organic amines are used as a neutralizing agent, an aqueous polyurethane resin dispersion is applied onto a glass plate and dried at a temperature of 60 ° C. under a reduced pressure of 20 mmHg for 24 hours to obtain a coating film of N. -It can be dissolved in methylpyrrolidone (NMP) and the acid value can be measured according to the indicator titration method of JIS K 1557.

The terminal acid value of the aqueous polyurethane resin dispersion is an acid value derived from (d) hydroxyalkanoic acid. The acid value at the end of the aqueous polyurethane resin dispersion is preferably 2 to 30 mgKOH / g, more preferably 5 to 20 mgKOH / g, based on the solid content. When the acid value at the end of the aqueous polyurethane resin dispersion is in the range of 2 to 30 mgKOH / g based on the solid content, the adhesion between the coating film obtained from the aqueous polyurethane resin dispersion and the base material tends to be improved.

The content ratio of the alicyclic structure in the aqueous polyurethane resin dispersion is not particularly limited, but is preferably 5 to 40% by weight, more preferably 5 to 30% by weight, and 5 to 30% by weight based on the solid content. It is particularly preferably 20% by weight. By setting the content ratio of the alicyclic structure in the aqueous polyurethane resin dispersion within the above range, there is a tendency that the elastic modulus of the obtained coating film can be increased and the adhesion between the coating film and the base material can be ensured.

The content of the tertiary carbon atom on the nitrogen atom of the amino group or imino group of the (B) chain extender in the aqueous polyurethane resin dispersion determines the storage stability of the obtained resin dispersion and the base material after baking. From the viewpoint of adhesion to water, 0.1 to 2.5% by weight is preferable, 0.15 to 2.0% by weight or more is more preferable, and 0.2 to 1% by weight is more preferable in the aqueous urethane resin dispersion based on the solid content. 5% by weight or more is particularly preferable.

Further, in the aqueous polyurethane resin dispersion of the present invention, if necessary, a thickener, a photosensitizer, a curing catalyst, an ultraviolet absorber, a light stabilizer, a defoaming agent, a plasticizer, a surface conditioner, and a sedimentation agent. Additives such as inhibitors can also be added. The additive may be used alone or in combination of two or more. Further, the types of these additives are known to those skilled in the art, and can be used in an amount in a range generally used.

<Paint composition, coating agent composition and ink composition>
The present invention also relates to a coating composition, a coating agent composition and an ink composition containing the aqueous polyurethane resin dispersion.
In addition to the above-mentioned aqueous polyurethane resin dispersion, other resins may be added to the coating composition, the coating agent composition and the ink composition. Examples of other resins include polyester resin, acrylic resin, polyether resin, polycarbonate resin, polyurethane resin, epoxy resin, alkyd resin, polyolefin resin, vinyl chloride resin and the like. These may be used alone or in combination of two or more. Other resins preferably have one or more hydrophilic groups. Examples of the hydrophilic group include a hydroxyl group, a carboxy group, a sulfonic acid group, a polyethylene glycol group and the like.

The other resin is preferably at least one selected from the group consisting of polyester resin, acrylic resin, and polyolefin resin.

The polyester resin can usually be produced by an esterification reaction or a transesterification reaction between an acid component and an alcohol component. As the acid component, a compound usually used as an acid component in the production of the polyester resin can be used. As the acid component, for example, an aliphatic polybasic acid, an alicyclic polybasic acid, an aromatic polybasic acid and the like can be used.

The hydroxyl value of the polyester resin is preferably about 10 to 300 mgKOH / g, more preferably about 50 to 250 mgKOH / g, and even more preferably about 80 to 180 mgKOH / g. The acid value of the polyester resin is preferably about 1 to 200 mgKOH / g, more preferably about 15 to 100 mgKOH / g, and even more preferably about 25 to 60 mgKOH / g.
The weight average molecular weight of the polyester resin is preferably 500 to 500,000, more preferably 1,000 to 300,000, still more preferably 1,500 to 200,000.

As the acrylic resin, a hydroxyl group-containing acrylic resin is preferable. The hydroxyl group-containing acrylic resin comprises a hydroxyl group-containing polymerizable unsaturated monomer and another polymerizable unsaturated monomer copolymerizable with the hydroxyl group-containing polymerizable unsaturated monomer, for example, by a solution polymerization method in an organic solvent, in water. It can be produced by copolymerizing by a known method such as the emulsion polymerization method of.
The hydroxyl group-containing polymerizable unsaturated monomer is a compound having one or more hydroxyl groups and one or more polymerizable unsaturated bonds in one molecule. For example, (meth) acrylic acid such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and 2 to 8 carbon atoms. Monoesterates with dihydric alcohols; ε-caprolactone modified products of these monoesterates; N-hydroxymethyl (meth) acrylamide; allyl alcohols; (meth) acrylates having a polyoxyethylene chain having a hydroxyl group at the molecular end. And so on.
Examples of other polymerizable unsaturated monomers include compounds having a polyfunctional polymerizable unsaturated bond such as trimethylolpropane triacrylate and divinylbenzene.

The hydroxyl group-containing acrylic resin preferably has an anionic functional group. As for the hydroxyl group-containing acrylic resin having an anionic functional group, for example, as one kind of the polymerizable unsaturated monomer, a polymerizable unsaturated monomer having an anionic functional group such as a carboxy group, a sulfonic acid group and a phosphoric acid group is used. Can be manufactured by.
The hydroxyl value of the hydroxyl group-containing acrylic resin is preferably about 1 to 200 mgKOH / g, more preferably about 2 to 100 mgKOH / g, and more preferably about 3 to 60 mgKOH from the viewpoint of storage stability of the composition and water resistance of the obtained coating film. About / g is more preferable.
When the hydroxyl group-containing acrylic resin has an acid group such as a carboxy group, the acid value of the hydroxyl group-containing acrylic resin is preferably about 1 to 200 mgKOH / g from the viewpoint of water resistance of the obtained coating film and the like. About 150 mgKOH / g is more preferable, and about 5 to 100 mgKOH / g is even more preferable.
The weight average molecular weight of the hydroxyl group-containing acrylic resin is preferably 1,000 to 200,000, more preferably 2,000 to 100,000, and even more preferably in the range of 3,000 to 50,000. be.

Examples of the polyether resin include polymers or copolymers having an ether bond, and examples thereof include aromatics such as polyoxyethylene-based polyether, polyoxypropylene-based polyether, polyoxybutylene-based polyether, bisphenol A, and bisphenol F. Examples thereof include polyethers derived from group polyhydroxy compounds.

Examples of the polycarbonate resin include polymers produced from bisphenol compounds, and examples thereof include bisphenol A and polycarbonate.

Examples of the polyurethane resin include resins having a urethane bond obtained by reacting various polyol components such as acrylic polyol, polyester polyol, polyether polyol, and polycarbonate polyol with polyisocyanate.

Examples of the epoxy resin include a resin obtained by the reaction of a bisphenol compound and epichlorohydrin. Examples of the bisphenol compound include bisphenol A and bisphenol F.

Alkyd resins include polybasic acids and polyhydric alcohols such as phthalic acid, terephthalic acid, and succinic acid, as well as fats and oils and fatty acids (soybean oil, flaxseed oil, palm oil, stearic acid, etc.), and natural resins (rosin, succinic acid, etc.). Etc.), and examples thereof include alkyd resins obtained by reacting with a modifying agent such as.

As the polyolefin resin, a polyolefin resin obtained by appropriately polymerizing or copolymerizing an olefin-based monomer with another monomer according to a usual polymerization method is water-dispersed using an emulsifier, or an olefin-based monomer is appropriately used as another monomer. Examples thereof include a resin obtained by emulsion polymerization together with the resin. Further, depending on the case, a so-called chlorinated polyolefin-modified resin in which the above-mentioned polyolefin resin is chlorinated may be used.

Examples of the olefin-based monomer include ethylene, propylene, 1-butane, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene and 1-. Α-olefins such as decene and 1-dodecene; conjugated diene or non-conjugated diene such as butadiene, etilidennorbornene, dicyclopentadiene, 1,5-hexadiene and styrenes, and these monomers may be used alone. Alternatively, a plurality of types may be used in combination.

Examples of other monomers copolymerizable with the olefin-based monomer include vinyl acetate, vinyl alcohol, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride, and itaconic anhydride. , It may be used alone, or a plurality of types may be used in combination.

The coating composition, the coating agent composition and the ink composition may contain a curing agent, whereby the coating composition or the coating agent composition obtained by using the coating composition or the coating agent composition, the coating film or the coating film or the printed matter. Water resistance and the like can be improved.

As the curing agent, for example, amino resin, polyisocyanate, blocked polyisocyanate, melamine resin, carbodiimide and the like can be used. The curing agent may be used alone or in combination of two or more.

Examples of the amino resin include a partially methylolated amino resin obtained by reacting an amino component with an aldehyde component. Examples of the amino component include melamine, urea, benzoguanamine, acetoguanamine, steroguanamine, spiroguanamine, dicyandiamide and the like. Examples of the aldehyde component include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and the like.

Examples of the polyisocyanate include compounds having two or more isocyanato groups in one molecule, and examples thereof include hexamethylene diisocyanate and trimethylhexamethylene diisocyanate.

Examples of the blocked polyisocyanate include those obtained by adding a blocking agent to the isocyanato group of the above-mentioned polyisocyanate, and examples of the blocking agent include phenolic compounds such as phenol and cresol, and aliphatic compounds such as methanol and ethanol. Alcohol type, active methylene type such as dimethyl malonate and acetylacetone, mercaptan type such as butyl mercaptan and dodecyl mercaptan, acid amide type such as acetanilide and acetate amide, lactam type such as ε-caprolactam and δ-valerolactam, succinate imide , Acidimide-based such as imide maleate, oxime-based such as acetaldehyde, acetone oxime, and methyl ethyl ketooxime, and amine-based blocking agents such as diphenylaniline, aniline, and ethyleneimine.

Examples of the melamine resin include methylol melamines such as dimethylol melamine and trimethylol melamine; alkyl ethers or condensates of these methylol melamines; and condensates of alkyl ethers of methylol melamine.

Coloring pigments, extender pigments, and brilliant pigments can be added to the coating composition, the coating agent composition, and the ink composition.
Examples of the coloring pigment include titanium oxide, zinc flower, carbon black, molybdenum red, Prussian blue, cobalt blue, azo pigment, phthalocyanine pigment, quinacridone pigment, isoindoline pigment, slene pigment, perylene pigment and the like. These may be used alone or in combination of two or more. In particular, it is preferable to use titanium oxide and / or carbon black as the coloring pigment.
Examples of the extender pigment include clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white. These may be used alone or in combination of two or more. In particular, it is preferable to use barium sulfate and / or talc as the extender pigment, and it is more preferable to use barium sulfate.
As the glitter pigment, for example, aluminum, copper, zinc, brass, nickel, aluminum oxide, mica, aluminum oxide coated with titanium oxide or iron oxide, or mica coated with titanium oxide or iron oxide can be used. ..

The paint composition, coating agent composition, ink composition, etc., if necessary, include thickeners, curing catalysts, ultraviolet absorbers, light stabilizers, defoamers, plasticizers, surface conditioners, anti-settling agents, etc. Can contain the usual additives of. These may be used alone or in combination of two or more.

The method for producing the coating composition, the coating agent composition and the ink composition is not particularly limited, but a known production method can be used. Generally, the coating composition and the coating agent composition are produced by mixing the above-mentioned aqueous polyurethane resin dispersion and the above-mentioned various additives, further adding an aqueous medium, and adjusting the viscosity according to the application method. Will be done.

Examples of the material to be coated of the coating composition, the material to be coated of the coating agent composition, or the material to be applied of the ink composition include metals, plastics, inorganic substances, wood, etc. can.
An electrodeposition coating plate is an object to be coated by immersing the object to be coated in a water-soluble paint and applying a DC voltage using the object to be coated as a cathode (or anode) and the paint as an opposite electrode of the object to be coated. It is a laminated board in which a coating film is formed on an object. In electrodeposition coating, even an object to be coated with a complicated shape can be painted in detail and can be painted automatically and continuously, so that a large and complicated shape such as an automobile body can be painted. It is preferable as an undercoat coating method for an object to be coated, which has a high rust preventive property. Further, it is economical because the use efficiency of the paint is extremely high as compared with other painting methods, and it is preferable as an industrial painting method. For example, cationic electrodeposition coating is performed by immersing an object to be coated in a cationic electrodeposition coating material having a cationic property as a cathode and applying a voltage.

Examples of the coating method of the coating composition or the coating method of the coating agent composition include bell coating, spray coating, roll coating, shower coating, and dip coating. Examples of the method of applying the ink composition include an inkjet printing method, a flexographic printing method, a gravure printing method, a reverse offset printing method, a sheet-fed screen printing method, and a rotary screen printing method.

It is preferable that the coating composition, the coating agent composition and the ink composition are applied to the material to be applied and then heat-cured to obtain a coating film and a coating.
Examples of the heating method include a heating method using its own reaction heat, a heating method for actively heating the coating composition, the coating agent composition, the ink composition, and the material to be applied. Examples of the active heating include a method in which the coating composition, the coating agent composition, the ink composition and the material to be applied are placed in a hot air oven, an electric furnace, or an infrared induction heating furnace to heat them.

The heating temperature is preferably 40 to 200 ° C, more preferably 60 to 160 ° C. By heating at such a temperature, drying can be performed more efficiently. The heating time is preferably 0.0001 to 20 hours, more preferably 1 to 10 hours. By setting such a heating time, a polyurethane resin film having higher hardness can be obtained. Drying conditions for obtaining the polyurethane resin film include, for example, heating at 120 ° C. for 3 to 10 seconds.
In particular, in the present invention, it is possible to form a coating film having high adhesion to a substrate at a relatively low temperature of about 80 to 90 ° C.

The thickness of the coating film after curing is not particularly limited, but a thickness of 1 to 100 μm is preferable. More preferably, a coating film having a thickness of 3 to 50 μm is formed.

<Polyurethane resin film>
The present invention further relates to a polyurethane resin film obtained from the aqueous polyurethane resin dispersion.

A polyurethane resin film can also be obtained by using an aqueous polyurethane resin dispersion. A polyurethane resin film can be obtained by applying an aqueous polyurethane resin dispersion to a releasable base material, drying and curing it by means such as heating, and then peeling a cured product of the polyurethane resin from the releasable base material. ..

Examples of the heating method include a heating method using its own reaction heat and a heating method in which the reaction heat and active heating of the mold are used in combination. Examples of active heating of the mold include a method of heating the mold in a hot air oven, an electric furnace, or an infrared induction heating furnace.

The heating temperature is preferably 40 to 200 ° C, more preferably 60 to 160 ° C. By heating at such a temperature, drying can be performed more efficiently. The heating time is preferably 0.0001 to 20 hours, more preferably 1 to 10 hours. By setting such a heating time, a polyurethane resin film having higher hardness can be obtained. Drying conditions for obtaining the polyurethane resin film include, for example, heating at 120 ° C. for 3 to 10 seconds.

The physical properties were measured as follows.
(1) Hydroxyl value: Measured according to the B method of JIS K 1557.
(2) Free NCO group content: 0.5 g of the reaction mixture after completion of the urethanization reaction was sampled and added to a mixed solution of 0.1 mol / L (liter) dibutylamine-hydrochloric acid (THF) solution (10 mL) and THF (20 mL). Then, the unconsumed dibutylamine was titrated with 0.1 mol / L hydrochloric acid. The molar concentration of NCO groups remaining in the reaction mixture was calculated from the difference between this titration value and the blank experiment. The molar concentration was converted to the weight fraction of the isocyanate group to obtain the free NCO group content. The indicator used for titration is bromophenol blue.

(3) Acid value: An aqueous polyurethane resin dispersion was applied onto a glass plate having a thickness of 0.2 mm and dried at a temperature of 60 ° C. under a reduced pressure of 20 mmHg for 24 hours to obtain a coating film. The obtained coating film was dissolved in N-methylpyrrolidone (NMP), and the acid value based on the solid content was measured according to the indicator titration method of JIS K 1557.
(4) Terminal acid value: For the terminal acid value, the acid value derived from (d) hydroxyalkanoic acid was calculated from the charging ratio of each raw material of the aqueous polyurethane resin dispersion and converted into a weight fraction. Notated.

(5) The solid content of the urethane bond and the solid content of the urea bond are determined by the molar concentration of the urethane bond and the urea bond (molar / g) based on the charging ratio of each raw material of the aqueous polyurethane resin dispersion. Was calculated and converted into a weight fraction. The weight fraction is based on the solid content of the aqueous polyurethane resin dispersion. 0.3 g of an aqueous polyurethane resin dispersion was applied onto a glass substrate to a thickness of 0.2 mm, and the weight remaining after heating and drying at 140 ° C. for 4 hours was measured, and this was divided by the weight before drying to form a solid. The concentration was defined as a minute concentration. The weight fraction was calculated by taking the product of the total weight of the aqueous polyurethane resin dispersion and the solid content concentration as the solid content weight.

(6) For the content based on the solid content of the carbonate bond, the molar concentration (molar / g) of the carbonate bond was calculated from the charging ratio of each raw material of the aqueous polyurethane resin dispersion and converted into a weight fraction. .. The weight fraction was calculated based on the solid content of the aqueous polyurethane resin dispersion in the same manner as the solid content of the urethane bond.
(7) For the content of the alicyclic structure based on the solid content, the weight fraction of the alicyclic structure calculated from the charging ratio of each raw material of the aqueous polyurethane resin dispersion is indicated. The weight fraction was calculated based on the solid content of the aqueous polyurethane resin dispersion in the same manner as the solid content of the urethane bond.

(8) Tertiary carbon atom content on the nitrogen atom of the amino group or imino group of the chain extender: From the charging ratio of each raw material of the aqueous polyurethane resin dispersion, on the nitrogen atom of the amino group or imino group of the chain extender The ratio of tertiary carbon atoms was calculated and converted into a weight fraction. The weight fraction was calculated based on the solid content of the aqueous polyurethane resin dispersion in the same manner as the solid content of the urethane bond.
(9) For the content of isocyanato groups (in terms of isocyanato groups) to which a solid content-based blocking agent is bound in the aqueous polyurethane resin dispersion, the amount of moles charged with the blocking agent is converted into the weight of the isocyanato groups, and the water is aqueous. The ratio of the polyurethane resin dispersion divided by the solid content weight is shown. The solid content weight of the aqueous polyurethane resin dispersion was calculated by the same method as the solid content of the urethane bond.

(10) Adhesion to the electrodeposited coated surface was evaluated as follows. An aqueous polyurethane resin dispersion is applied to an automobile steel sheet cationic electrodeposition coating plate (manufactured by Nippon Test Panel Co., Ltd.) with a thickness of 40 μm (bar coater # 20) and dried by heating at 90 ° C. for 30 minutes, or at 80 ° C. for 20 minutes. A grid peeling test was performed using the obtained coating film for each of the cases of heat drying. Cuts were made in the coating film in an area of 10 mm × 10 mm at 1 mm intervals, and after the adhesive tape was attached, the number of squares remaining when the adhesive tape was peeled off was visually counted and evaluated. For example, the case where 60 out of 100 remained was described as 60/100.

(11) The elastic modulus of the polyurethane resin was measured by a method according to JIS K 7311. The measurement conditions were a measurement temperature of 23 ° C., a humidity of 50%, and a tensile speed of 100 mm / min.

[Example 1]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1965; hydroxyl value 57.1 mgKOH / g, 199 g) and 2,2-di. 80 of methylolpropionic acid (14.3 g) and hydrogenated MDI (93.7 g) in dipropylene glycol dimethyl ether (67.5 g) in the presence of dibutyltin dilaurylate (0.2 g) and in a nitrogen atmosphere. It was heated at ~ 90 ° C. for 4 hours. The NCO group content at the end of the urethanization reaction was 3.21% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (11.3 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 353 g was extracted and added to water (630 g) with strong stirring, and then N, N'-di-tert-butylethylenediamine (17.8 g) represented by the following formula was used as a chain extender. In addition, an aqueous polyurethane resin dispersion was obtained.

[Example 2]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1957; hydroxyl value 57.3 mgKOH / g, 400 g) and 2,2-di. Methylolpropionic acid (25.4 g) and isophorone diisocyanate (122 g) in dipropylene glycol dimethyl ether (177 g) in the presence of dibutyltin dilaurylate (0.4 g) in a nitrogen atmosphere at 80-90 ° C. 5 Heated for hours. The NCO group content at the end of the urethanization reaction was 2.03% by weight. After the reaction mixture was brought to 80 ° C., 19.1 g of triethylamine) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 595 g was extracted and placed in water (909 g) with strong stirring, and then N, N'-di-tert-butylethylenediamine (19.3 g) was added as a chain extender to disperse the aqueous polyurethane resin. I got a body.

[Example 3]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1957; hydroxyl value 57.3 mgKOH / g, 250 g) and 2,2-di. Dibutyltin dilaurylate (0.3 g) of methylolpropionic acid (8.7 g), 12-hydroxystearic acid (34.0 g), and isophorone diisocyanate (77.9 g) in dipropylene glycol dimethyl ether (120 g). In the presence and in a nitrogen atmosphere, it was heated at 80-90 ° C. for 4.5 hours. The NCO group content at the end of the urethanization reaction was 1.56% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (17.5 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 431 g was extracted and placed in water (650 g) with strong stirring, and then N, N'-di-tert-butylethylenediamine (11.6 g) was added as a chain extender to disperse the aqueous polyurethane resin. I got a body.

[Example 4]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1957; hydroxyl value 57.3 mgKOH / g, 500 g) and 2,2-di. Methylolpropionic acid (17.1 g), 12-hydroxystearic acid (66.5 g), and isophorone diisocyanate (153 g) in dipropylene glycol dimethyl ether (236 g) in the presence of dibutyltin dilaurylate (0.6 g). , Heated at 80-90 ° C. for 4.5 hours in a nitrogen atmosphere. The NCO group content at the end of the urethanization reaction was 1.57% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (34.3 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 428 g was extracted and added to water (656 g) with vigorous stirring, and then 35 wt% diethylenetriamine aqueous solution (3.5 g) and N, N'-di-tert-butylethylenediamine were used as chain extenders. (9.2 g) was added to obtain an aqueous polyurethane resin dispersion.

[Example 5]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1957; hydroxyl value 57.3 mgKOH / g, 500 g) and 2,2-di. Methylolpropionic acid (17.1 g), 12-hydroxystearic acid (66.5 g), and isophorone diisocyanate (153 g) in dipropylene glycol dimethyl ether (236 g) in the presence of dibutyltin dilaurylate (0.6 g). , Heated at 80-90 ° C. for 4.5 hours in a nitrogen atmosphere. The NCO group content at the end of the urethanization reaction was 1.57% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (34.3 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 428 g was extracted and added to water (631 g) with vigorous stirring, and then 35 wt% diethylenetriamine aqueous solution (6.8 g) and N, N'-di-tert-butylethylenediamine were used as chain extenders. (6.0 g) was added to obtain an aqueous polyurethane resin dispersion.

[Example 6]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1957; hydroxyl value 57.3 mgKOH / g, 250 g) and 2,2-di. Dibutyltin dilaurylate (0.3 g) of methylolpropionic acid (8.6 g), 12-hydroxystearic acid (33.3 g), and isophorone diisocyanate (75.9 g) in dipropylene glycol dimethyl ether (118 g). In the presence and in a nitrogen atmosphere, it was heated at 80-90 ° C. for 4 hours. The NCO group content at the end of the urethanization reaction was 1.79% by weight. After the reaction mixture was brought to 80 ° C., 17.1 g of triethylamine) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 428 g was extracted and added to water (625 g) with vigorous stirring, and then 35 wt% diethylenetriamine aqueous solution (11.1 g) and N, N'-di-tert-butylethylenediamine were used as chain extenders. (3.4 g) was added to obtain an aqueous polyurethane resin dispersion.

[Example 7]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1957; hydroxyl value 57.3 mgKOH / g, 250 g) and 2,2-di. Methylolpropionic acid (8.6 g), 12-hydroxystearic acid (33.3 g), 3,5-dimethylpyrazole (dissociation temperature 100-110 ° C.) (7.3 g), and isophorone diisocyanate (77.5 g). Was heated in dipropylene glycol dimethyl ether (118 g) in the presence of dibutyltin dilaurylate (0.3 g) in a nitrogen atmosphere at 80 to 90 ° C. for 5 hours. The NCO group content at the end of the urethanization reaction was 0.93% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (17.1 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 434 g was extracted and placed in water (627 g) with strong stirring, and then N, N'-di-tert-butylethylenediamine (6.8 g) was added as a chain extender to disperse the aqueous polyurethane resin. I got a body.

[Example 8]
A reactor equipped with a stirrer and a heater, with polycarbonate polyol (product name: Clare polyol C-2090 (manufactured by Kurare Co., Ltd.), number average molecular weight 1993; hydroxyl value 56.3 mgKOH / g, 402 g) and 2,2-di. Dibutyltin dilaurylate (0.5 g) present in dipropylene glycol dimethyl ether (202 g) with methylol propionic acid (28.1 g), 3,5-dimethylpyrazole (12.3 g) and hydrogenated MDI (183 g). Underneath, it was heated at 80 to 90 ° C. for 4 hours in a nitrogen atmosphere. The NCO group content at the end of the urethanization reaction was 2.17% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (22.5 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 390 g was extracted and placed in water (862 g) with strong stirring, and then N, N'-di-tert-butylethylenediamine (17.3 g) was added as a chain extender to disperse the aqueous polyurethane resin. I got a body.

[Comparative Example 1]
A reactor equipped with a stirrer and a heater, with polycarbonate polyol (product name: Clare polyol C-2090 (manufactured by Kurare Co., Ltd.), number average molecular weight 1993; hydroxyl value 56.3 mgKOH / g, 402 g) and 2,2-di. Methylolpropionic acid (28.1 g), hydrogenated MDI (183 g) and 3,5-dimethylpyrazole (12.3 g) in dipropylene glycol dimethyl ether (202 g) in the presence of dibutyltin dilaurylate (0.5 g). , Heated at 80-90 ° C. for 4 hours in a nitrogen atmosphere. The NCO group content at the end of the urethanization reaction was 2.17% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (22.5 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 398 g was extracted and placed in water (819 g) with strong stirring, and then a 35 wt% 2-methyl-1,5-diaminopentane aqueous solution (31.9 g) was added as a chain extender to add aqueous solution. A polyurethane resin dispersion was obtained.

[Comparative Example 2]
In a reactor equipped with a stirrer and a heater, polycarbonate diol (product name ETERNAL COLL UH-200 (registered trademark; manufactured by Ube Kosan); number average molecular weight 2029; hydroxyl value 55.3 mgKOH / g, 2140 g) and 2,2- Dimethylolpropionic acid (153 g), hydrogenated MDI (963 g) and 3,5-dimethylpyrazole (31.1 g) in N-methylpyrrolidone (1090 g) in the presence of dibutyltin dilaurylate (2.6 g). , Heated at 80-90 ° C. for 5 hours in a nitrogen atmosphere. The NCO group content at the end of the urethanization reaction was 2.41% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (115 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 4180 g was withdrawn and placed in water (6410 g) with strong stirring, and then adipic acid dihydrazide (183 g) was added as a chain extender to obtain an aqueous polyurethane resin dispersion.

[Comparative Example 3]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1979; hydroxyl value 56.7 mgKOH / g, 300 g) and 2,2-di. Methylolpropionic acid (13.7 g) and isophorone diisocyanate (82.0 g) in N-methylpyrrolidone (131 g) in the presence of dibutyltin dilaurylate (0.3 g) in a nitrogen atmosphere at 80 to 90 ° C. Was heated for 6 hours. The NCO group content at the end of the urethanization reaction was 1.63% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (10.3 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 480 g was extracted and placed in water (680 g) with strong stirring, and then a 35 wt% 2-methyl-1,5-diaminopentane aqueous solution (16.2 g) was added as a chain extender to add aqueous solution. A polyurethane resin dispersion was obtained.

[Comparative Example 4]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1979; hydroxyl value 56.7 mgKOH / g, 320 g) and 2,2-di. Methylolpropionic acid (12.8 g) and isophorone diisocyanate (96.2 g) in N-methylpyrrolidone (139 g) in the presence of dibutyltin dilaurylate (0.4 g) in a nitrogen atmosphere at 80 to 90 ° C. Was heated for 5.5 hours. The NCO group content at the end of the urethanization reaction was 2.48% by weight. After the reaction mixture was brought to 80 ° C., triethylamine (10.2 g) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 557 g was extracted and put into water (820 g) with strong stirring, and then 35 wt% diethylenetriamine (27.6 g) was added as a chain extender to obtain an aqueous polyurethane resin dispersion.

[Comparative Example 5]
A reactor equipped with a stirrer and a heater, with polytetramethylene glycol (product name (PTMG2000) (manufactured by Mitsubishi Chemical Corporation), number average molecular weight 1962; hydroxyl value 57.2 mgKOH / g, 299 g) and 2,2-di. Dibutyltin dilaurylate (0) of methylolpropionic acid (9.80 g), 12-hydroxystearic acid (27.1 g) and hydrogenated MDI (98.9 g) in N-ethylpyrrolidone (85.5 g). .3 g) In the presence, in a nitrogen atmosphere, heated at 80-90 ° C. for 6 hours. The NCO group content at the end of the urethanization reaction was 1.65% by weight. After the reaction mixture was brought to 80 ° C., 17.0 g of triethylamine) was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 505 g was extracted and put into water (870 g) with strong stirring, and then a 35 wt% diethylenetriamine aqueous solution (17.9 g) was added as a chain extender to obtain an aqueous polyurethane resin dispersion.

The abbreviations and abbreviations in the table are as follows.
H12-MDI: 4,4'-dicyclohexylmethane diisocyanate IPDI: Isophorone diisocyanate PTMG2000: Polytetramethylene ether glycol C-2090: Kuraray polyol C-2090
UH-200: ETERNAL COLL® UH-200
HS: 12-Hydroxystearate DMPZ: 3,5-dimethylpyrazole DBEDA: N, N'-di-tert-butylethylenediamine MPMD: 2-methyl-1,5-pentanediamine DETA: Diethylenetriamine ADH: dihydrazide adipicate DMPA: 2,2-Dimethylolpropionate Urethane bond content: Urethane bond solid content standard content Urea bond content: Urea bond solid content standard content Urethane bond and urea bond total content: Urethane bond solid content standard Total of content and solid content of urethane bond Carbonated bond content: Solid content of carbonate bond Oil ring structure content: Solid content of oil ring structure Blocked NCO content: Aqueous polyurethane resin Content of isocyanato group to which a solid content-based blocking agent is bound in the dispersion (isocyanato group conversion)
Tertiary carbon structure content: The chain extender has a tertiary carbon atom on the nitrogen atom of the amino or imino group:

From the comparison between Examples 1 to 8 and Comparative Examples 1 to 5, it is determined that the chain extender contains a compound having at least one tertiary carbon atom on the nitrogen atom of the amino group or the imino group. It can be seen that the adhesion of is excellent.
Further, from the comparison between Examples 1 and 2 and Examples 3 to 5, the water-soluble polyurethane resin dispersion having a structure derived from 12-hydroxystearic acid has a higher adhesion to the electrodeposited coated surface by baking at a lower temperature. It turns out to be excellent.
Further, from the comparison between Example 8 and Example 1, it can be seen that the elastic modulus is excellent when the polycarbonate diol is used as the raw material of the polyurethane prepolymer.
Further, from Examples 7 and 8, even when a blocking agent having a dissociation temperature of 100 to 110 ° C. is used in the production of the polyurethane prepolymer, sufficient adhesion can be exhibited by baking at 90 ° C. Recognize. In particular, in Example 7 in which the polyether diol was used as the raw material of the polyurethane prepolymer, sufficient adhesion was exhibited even in baking at 80 ° C.

The aqueous polyurethane resin dispersion of the present invention can be widely used as a raw material for paints, coating agents, primers, adhesives, inks, films and the like.

Claims (10)

A polyurethane resin composed of (A) a polyurethane prepolymer having at least one isocyanato group and (B) a chain extender having two or more amino groups or imino groups in one molecule is dispersed in an aqueous medium. Aqueous polyurethane resin dispersion
(B) An aqueous polyurethane resin dispersion in which the chain extender contains a compound having at least one tertiary carbon atom on the nitrogen atom of at least one amino group or imino group. The aqueous polyurethane according to claim 1, wherein the polyurethane prepolymer has a structure derived from (a) a polyisocyanate compound, a structure derived from a polyol compound, and a structure derived from an acidic group-containing polyol compound. Resin dispersion. 2. Claim 2 that the polyurethane prepolymer (A) further has a structure derived from (d) hydroxyalkanoic acid and / or (e) a structure derived from an isocyanato group blocking agent that dissociates at 80 ° C to 180 ° C. Aqueous polyurethane resin dispersion according to. The aqueous polyurethane resin dispersion according to claim 2 or 3, wherein the polyol compound (b) is a polycarbonate polyol. The claim that the content of the tertiary carbon atom on the nitrogen atom of the amino group or imino group of the chain extender (B) is 0.1% by weight or more based on the solid content in the aqueous polyurethane resin dispersion. The aqueous polyurethane resin dispersion according to any one of 1 to 4. The compound having at least one tertiary carbon atom on the nitrogen atom of the at least one amino group or imino group is the following formula (A), formula (B), formula (C), formula (D) and formula. Claims 1 to 5 which are compounds having at least one structure represented by (E) ( excluding compounds having a structure represented by the formula (A) and having a nitrogen atom of the formula (A) bonded to an aromatic ring). The aqueous polyurethane resin dispersion according to any one of the above items.

(The above formula (A), Formula ^{(B), R 1, R} 2, R 3 in the formula (C), formula (D) and Formula (E) is a substituted or unsubstituted C1~C6 alkyl group, Substituentally substituted or unsubstituted C6-C20 cycloalkyl groups or substituted or unsubstituted C6-C12 aryl groups are indicated, and R ⁴ , R ⁵ , and R ⁶ are substituted or unsubstituted C1 to C6 alkyl groups. Indicates a substituted or unsubstituted C6-C20 cycloalkyl group, a substituted or unsubstituted C6-C12 aryl group, or hydrogen. R ^{1 to} R ⁶ are bonded to each other to form an alicyclic structure or an aromatic ring. Also, CT in formula (B) and formula (E) indicates a tertiary carbon atom.) A coating composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 6. A coating agent composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 6. An ink composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 6. A polyurethane resin film obtained by drying and curing a composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 6.