JP4573155B2 - Water-based polyurethane resin, water-based polyurethane resin aqueous dispersion, printing ink binder and printing ink composition - Google Patents

Description

  The present invention relates to an aqueous polyurethane resin, a binder for printing ink containing the aqueous polyurethane resin, a printing ink, and a method for producing an aqueous dispersion of an aqueous polyurethane resin. More specifically, the water-based polyurethane resin of the present invention has excellent adhesion to various base materials such as plastics such as polypropylene, nylon, and polyester, metal, glass, paper, rubber, and leather. The present invention relates to a water-based polyurethane resin that can be suitably used for various applications such as various coating agents (for example, paints, inks, glass scattering prevention films, etc.), and various adhesives and pressure-sensitive adhesives applied to these substrates. .

  In the past, polymer organic solvent solutions were mainly used as coating agents and adhesives for paints and inks. However, in recent years, pollution such as air pollution, fire regulations, occupational safety・ In consideration of hygiene, etc., water-soluble polymers and polymer emulsions are being replaced.

As the water-soluble polymer, an aqueous polyurethane resin having a feature in flexibility has been developed in recent years, but a polar group or the like for making the resin aqueous is imparted to the resin molecule ( For example, the adhesiveness with respect to plastics (refer patent document 1) and a plastic (especially polyolefin which does not have a polar group) was inadequate.

  Therefore, the present applicant has proposed a polyurethane resin for printing ink using a long-chain monoamine compound as a chain length terminator in order to improve adhesion to plastic (see Patent Document 2). It relates to a polyurethane resin to be dissolved in a solvent other than the above, and cannot be used as an aqueous polyurethane resin, and the problem to be solved is also different.

Japanese Patent Laid-Open No. 11-269243 JP 2001-233929 A

  The present invention has been made in view of the above-described background art, and has an object of having flexibility unique to an aqueous polyurethane resin and excellent for plastics such as polyolefin (polyethylene, polypropylene, etc.), nylon, polyester, and the like. Another object of the present invention is to provide an aqueous polyurethane resin having excellent adhesion.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that adhesion to a plastic (particularly polyolefin) substrate is improved by using a specific neutralizing agent during the production of aqueous polyurethane. It was.

  That is, in the present invention, an isocyanate group-terminated prepolymer (A) containing a carboxyl group obtained by reacting a polymer polyol (a-1) and a polyisocyanate compound (a-2) is represented by the general formula (1):

(R ¹ represents an alkyl group having 4 to 18 carbon atoms, A represents an oxyalkylene group having 2 carbon atoms, A may be different or the same, and x represents an integer of 1 to 10 . A water-based polyurethane resin obtained by neutralization using an amine compound (B) which is an amine compound represented by formula (1), dimethyl palmitylamine or dilauryl monomethylamine; water-based polyurethane resin water in which the water-based polyurethane resin is dispersed in water The present invention relates to a printing ink binder comprising a dispersion and the aqueous polyurethane resin; and a printing ink composition comprising the printing ink binder.

  According to the present invention, it has flexibility specific to an aqueous polyurethane resin, and particularly has excellent adhesion to plastics such as polyolefin (polyethylene, polypropylene, etc.), nylon and polyester when used as a binder for printing ink. An aqueous polyurethane resin can be provided. In addition, since the said water-based polyurethane resin has the outstanding adhesiveness with respect to various base materials, such as a plastic, a metal, glass, paper, rubber | gum, leather, various coating agents (for example, paints) applied to these base materials. , Ink, glass scattering prevention film, etc.) and various adhesives and pressure-sensitive adhesives applied to these substrates.

The aqueous polyurethane resin of the present invention is a specific amine compound (B) (hereinafter referred to as (B) component) which will be described later with respect to the isocyanate group-terminated prepolymer (A) (hereinafter referred to as (A) component) containing a carboxyl group. Obtained by neutralization.

(A) component used for this invention will not be restrict | limited especially if it has a carboxyl group, A well-known thing can be used, Usually, polymer polyol (a-1) (henceforth, (a- 1) component) and a polyisocyanate compound (a-2) (referred to as component (a-2)). The method for introducing a carboxyl group into the polyurethane resin is not particularly limited, and a known method can be adopted. Specifically, for example, (i) a method using a carboxyl group-containing diol compound (hereinafter referred to as method (i)), (ii) a method using a chain extender containing a carboxyl group (hereinafter referred to as method (ii)). Etc.) is preferable because a carboxyl group can be easily introduced.

As the component (a-1), various polyols used for the production of polyurethane can be used without limitation. For example, polyether polyols, polyester polyols, polycarbonate polyols, polybutadiene polyols, and the like are used. Can do. Examples of the polyether polyols include polyethylene glycol obtained by ring-opening polymerization of ethylene oxide, propylene oxide, tetrahydrofuran and the like, polypropylene glycol, polyoxytetramethylene ether glycol and the like. Examples of polyester polyols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, Saturated or unsaturated low molecular weight glycols such as 3-methyl-1,5-pentanediol, 1,6-hexanediol, octanediol, 1,4-butynediol, dipropylene glycol, bisphenol A and hydrogenated bisphenol A And dibasic acids such as adipic acid, maleic acid, fumaric acid, phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, azelaic acid, sebacic acid, suberic acid, etc. Acid anhydrides corresponding to Water condensation compound obtained, and the like. In addition, trivalent alcohols such as glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, etc. up to a range of 5 mol% or less of the low molecular weight glycols, A trihydric or higher polyhydric low molecular weight polyol compound such as a tetravalent alcohol such as pentaerythritol and a hexavalent alcohol such as sorbitol can be used in combination. As the polyester polyols, compounds obtained by ring-opening polymerization of lactones such as ε-caprolactone and β-methyl-δ-valerolactone can also be used. These high molecular weight polyol compounds may be used alone or in combination of two or more.

The number average molecular weight of the component (a-1) is usually about 500 to 10,000, preferably 700 to 5,000. If the value is too small, the resulting polyurethane resin film tends to have poor flexibility, and if it is too large, the urethane prepolymer is not quickly dispersed in an aqueous solution containing a neutralizing agent and a chain extender. The drying property of the polyurethane resin film tends to be inferior.

In addition, when using method (i) as a method of introduce | transducing a carboxyl group into an isocyanate group terminal prepolymer, what is necessary is just to use a carboxyl group containing diol compound as a part or all of (a-1) component. Examples of carboxyl group-containing diol compounds include α, α′-dimethylolalkanoic acid (glyceric acid, dimethylolpropionic acid, dimethylolbutanoic acid, 2,2-dimethylolpentanoic acid, etc.), dioxymaleic acid, and dioxyfumarate. Examples include acid, tartaric acid, 2,6-dioxybenzoic acid, 4,4-bis (hydroxyphenyl) valeric acid, 4,4-bis (hydroxyphenyl) butyric acid, and the like. In addition, compounds obtained by ring-opening polymerization of lactones such as ε-caprolactone, γ-butyrolactone, γ-valerolactone, etc. using diol compounds containing these carboxyl groups as initiators, and ring-opening polymerization of lactones The resulting high molecular weight compounds can also be used.

  Examples of the component (a-2) include diisocyanates. Examples of the diisocyanate include methylene diisocyanate, isopropylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and dimer acid. A chain aliphatic diisocyanate such as dimerisocyanate in which the carboxyl group of the compound is replaced by an isocyanate group; cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, 1,3-di (isocyanate methyl) Cycloaliphatic diisocyanates such as cyclohexane and methylcyclohexane diisocyanate; 4,4′-diphenyldimethylmethane Dialkyldiphenylmethane diisocyanate such as isocyanate, tetraalkyldiphenylmethane diisocyanate such as 4,4′-diphenyltetramethylmethane diisocyanate, 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate, Aromatic diisocyanates such as 4,4′-dibenzyl isocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, m-tetramethylxylylene diisocyanate; amino acid diisocyanates such as lysine diisocyanate Etc. These diisocyanates are used alone or in combination of two or more. Among these diisocyanates, it is preferable to use a chain aliphatic diisocyanate and a cyclic aliphatic diisocyanate because weather resistance can be improved.

  In the water-based polyurethane resin of the present invention, a chain extender can be used as a constituent component in addition to the components (a-1) and (a-2) as necessary. Examples of the chain extender include low-molecular glycols that are constituent materials of the component (a-1); ethylenediamine, propylenediamine, hexamethylenediamine, 2,2,4- or 2,4,4-trimethylhexa Amines such as methylenediamine, triethylenetetramine, diethylenetriamine, isophoronediamine, dicyclohexylmethane-4,4′-diamine; 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2 -Diamines having a hydroxyl group in the molecule such as hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine; and replacing the carboxyl group of dimer acid with an amino group Dimer diamine, hydrazine, and the like adipic acid dihydrazide. These chain extenders may be used alone or in appropriate combination of two or more.

  Moreover, the compound which has an ionic functional group can be used as the said chain extender in order to provide an ionic functional group to a polyurethane resin, and to improve the dispersibility to water. The ionic functional group is not particularly limited, and examples thereof include a quaternary amino base and a carboxyl group. Specific examples of the compound include N-methyldiethanolamine, N-ethyldiethanolamine, N-propyldiethanolamine, N-isopropyldiethanolamine, N-butyldiethanolamine, N-isobutyldiethanolamine, N-oleyldiethanolamine, N-stearyldiethanolamine, ethoxylation Palm oil amine, N-allyldiethanolamine, N-methyldiisopropanolamine, N-ethyldiisopropanolamine, N-propyldiisopropanolamine, N-butyldiisopropanolamine, dimethyldiethoxyhydrazine, propoxymethyldiethanolamine, N- (3 -Aminopropyl) -N-methylethanolamine, N, N′-bis (oxyethyl) propylenediamine, dietano Alkoxylated chain aliphatic amines such as ruaminoacetamide, diethanolaminopropionamide, N, N-bis (oxymethyl) semicarbazide; alkoxylated cycloaliphatic amines such as N-cyclohexyldiisopropanolamine; N, N-diethoxy Aniline, N, N-diethoxytoluidine, N, N-diethoxy-1-aminopyridine, N, N′-bis (2-hydroxyethyl) -N, N′-diethylhexahydro-p-phenylenediamine, N, Alkoxylated aromatic amines such as N′-bis (oxyethyl) phenyl semicarbazide; alkoxylated heterocyclic amines such as N, N′-diethoxypiperazine, N-2-hydroxyethylpiperazine; N-methyl-N, N-bis (3-aminopropyl) amine, N- (3-aminopro ) -N, N′-dimethylethylenediamine, N, N′-bis (3-aminopropyl) -N, N′-dimethylethylenediamine, 2-methyl-2-[(N, N-dimethylamino) methyl] propane Chain aliphatic amines such as 1,3-diol; aromatic amines such as 2,6-diaminopyridine and p, p′-bis-aminomethyldibenzylmethylamine; N, N′-bis (3-amino And heterocyclic amines such as propyl) piperazine and N- (2-aminoethyl) piperazine. The basic nitrogen of the chain extender is quaternized such as chloride ion, sulfate ion, organic carboxylic acid anion before or after the chain extender is dispersed in water. It may be quaternized with an agent.

  Since the chain extender having a carboxyl group can be used to introduce a carboxyl group into the resulting aqueous polyurethane resin, when the carboxyl group-containing diol compound is not used as the component (A), the chain extender has the carboxyl group. It is necessary to use a chain extender. Specific examples thereof include glyceric acid, dioxymaleic acid, dioxyfumaric acid, tartaric acid, dimethylolpropionic acid, dimethylolbutanoic acid, 2,2-dimethylolvaleric acid, 2,2-dimethylolpentanoic acid, 4,4- Examples thereof include aliphatic carboxylic acids such as di (hydroxyphenyl) valeric acid and 4,4-di (hydroxyphenyl) butyric acid; and aromatic carboxylic acids such as 2,6-dioxybenzoic acid.

  The amount of the chain extender used is not particularly limited, but is 0.1 to 20% by weight in the aqueous polyurethane resin from the viewpoint of achieving both flexibility and toughness of the film formed from the obtained aqueous polyurethane resin. The amount is preferably about 1 to 15% by weight. When it is less than 0.1% by weight, the toughness tends to be insufficient, and when it exceeds 20% by weight, the flexibility tends to be impaired.

When the chain extender having an ionic functional group is used, the amount of the extender used is not particularly limited. For example, basic nitrogen in the polyurethane resin having basic nitrogen is 1 g of the polyurethane resin solid content. It is preferable to adjust so that it may become about 3 * 10 < ^-5 > -1.8 * 10 < ^-3 > gram equivalent with respect to it. The amount of the chain extender having a carboxyl group among the chain extenders having an ionic functional group is not particularly limited. For example, the carboxyl group in the polyurethane resin has a solid content of 1 g of the polyurethane resin. It is preferable to adjust so that it may become about 3 * 10 < ^-5 > -1.8 * 10 < ^-3 > gram equivalent with respect to it.

There is no particular limitation on the timing of reacting the chain extender, and the chain extender may be reacted simultaneously with the component (a-1) and the component (a-2), and the component (a-1) and the component (a-2) may be reacted. The prepolymer obtained by the reaction may be reacted before being dispersed in water or after being dispersed in water.

In the aqueous polyurethane resin of the present invention, the carboxyl group derived from the component (a-1) and / or the carboxyl group derived from the chain extender has the general formula (1):

(R ¹ represents an alkyl group having 4 to 18 carbon atoms, A represents an oxyalkylene group having 2 carbon atoms, A may be different or the same, and x represents an integer of 1 to 10 . ), An amine compound (B) (hereinafter referred to as (B) component) which is an amine compound, dimethyl palmitylamine or dilauryl monomethylamine.

Specific examples of the component ( B) include polyoxyethylene octadecylamine, polyoxyethylene dodecylamine, polyoxyethylene octylamine, Nn-butyldiethanolamine , and dilauryl monomethylamine. Among these, polyoxyethylene octadecylamine, polyoxyethylene dodecylamine, di-methyl palmityl amine, dilauryl monomethylamine is preferable.

  In addition, although what has a hydroxyl group among these (B) components can also be a chain extender, when using these as a chain extender (namely, thing which reacts with isocyanate), the effect ( (Improvement of adhesion to plastic) cannot be obtained. The reason for this is not clear, but because the compound is present in the hydrophilic portion (near the surface of the emulsion particles) by using the component (B) having a hydroxyl group as a neutralizing agent, wetting to the film is improved. Conceivable.

  The amount of component (B) used is appropriately determined according to the amount of carboxyl group contained in component (A), but is usually about 0.1 to 3 equivalents relative to the carboxyl group, preferably 0.3 to 1.5 equivalents. Setting it to 0.3 equivalent or more is preferable because adhesion is improved, and setting it to 1.5 or less is preferable because blocking resistance is improved.

  The aqueous polyurethane resin of the present invention can be produced by reacting the various components using a known method. In the aqueous polyurethane resin of the present invention, a hydroxyl group in the component (a-1) mainly reacts with an isocyanate group in the component (a-2) to form a urethane bond. The number average molecular weight of the aqueous polyurethane resin of the present invention is not particularly limited, but it is usually preferably about 3,000 to 1,000,000. When it is less than 3,000, the film strength tends to be insufficient, and when it exceeds 1,000,000, it tends to be inferior in re-solubility when used as a binder for printing ink. The aqueous polyurethane resin of the present invention can be obtained by reacting each of the above components, but usually it is not isolated as a solid content of the aqueous polyurethane resin, but is used as it is as a binder for printing ink in the form of an aqueous solution. Below, the manufacturing method of the binder for printing ink is demonstrated more concretely.

  There are the following methods for dispersing the aqueous polyurethane resin of the present invention in water. 1) Component (a-1) and component (a-2) are subjected to a condition in which the amount of NCO group of component (a-2) is excessive with respect to the total amount of hydroxyl groups of component (a-1). A urethanization reaction is performed to produce a prepolymer having an NCO group at the molecular end, a solution in which the prepolymer is dissolved in an appropriate organic solvent is prepared, and the chain extender having an ionic functional group is added to the solution. And then neutralizing with the neutralizing agent (quaternizing with a quaternizing agent if necessary) and then dispersing this in water, 2) component (a-1), ( a-2) A chain extender mixture containing the component and the chain extender having an ionic functional group is charged all at once, reacted in an appropriate organic solvent, and then neutralized with the neutralizer (necessary) Quaternization using a quaternizing agent according to the method, and then dispersing in water, 3) (a- ) Component, (a-2) component, and a chain extender mixture containing the chain extender having an ionic functional group, (a-1) containing the component and the chain extender having an ionic functional group The active hydrogen group of the chain extender mixture is reacted in an appropriate organic solvent under the condition that the NCO group of component (a-2) is excessive to produce a prepolymer having an NCO group at the molecular end. And neutralize with the neutralizing agent (excluding those having a hydroxyl group) (quaternization with a quaternizing agent if necessary), and then disperse in water. In addition, there is a method of reacting.

The organic solvent is not particularly limited as long as it is non-reactive with the above components, and various known solvents can be used. Specific examples of the organic solvent include aromatic solvents such as benzene, toluene, and xylene; ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, and methyl isobutyl ketone; dimethylformamide Amide solvents such as: sulfoxide solvents such as dimethyl sulfoxide; ether solvents such as dimethyl ether and diethyl ether; alcohols such as isopropyl alcohol and ethanol; N-methylpyrrolidone and the like. Alternatively, two or more kinds are used in appropriate combination.

  The printing ink binder thus obtained can be kneaded and dispersed by adding a pigment or the like to prepare a printing ink composition. When preparing the printing ink composition, if necessary, an aqueous polyurethane resin, an aqueous polyamide resin, an aqueous acrylic ester copolymer salt, an aqueous styrene-maleic acid copolymer different from the aqueous polyurethane resin of the present invention are used. An aqueous resin such as a polymer salt, and additives such as an antiblocking agent and a plasticizer can be appropriately blended.

  Next, although the water-based polyurethane resin of this invention is demonstrated more concretely based on an Example, this invention is not limited only to this Example.

Example 1
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 1163.5 parts of water, 74.7 parts of isopropyl alcohol, 126.4 parts of polyoxyethylene octadecylamine (number average molecular weight 709) and 40.4 parts of adipic acid dihydrazide were charged and mixed uniformly. The whole amount of the urethane prepolymer was added to the bottom and reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 400 mPa · s / 25 ° C., a pH of 7.2, and a number average molecular weight of 13,000.

Example 2
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 1239.1 parts of water, 74.7 parts of isopropyl alcohol, 167.1 parts of polyoxyethylene dodecylamine (number average molecular weight 625) and 40.4 parts of adipic acid dihydrazide were charged and mixed uniformly. The whole amount of the urethane prepolymer was added to the bottom and reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 300 mPa · s / 25 ° C., a pH of 7.6, and a number average molecular weight of 10,000.

Example 3
In a reaction vessel equipped with a stirrer, a thermometer, a cooling pipe and a nitrogen gas introduction pipe, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 964.3 parts of water, 74.7 parts of isopropyl alcohol, 24.0 parts of dimethyl palmitylamine, 9.0 parts of triethylamine, and 40.4 parts of adipic dihydrazide were mixed and mixed uniformly. All of the urethane prepolymer was added to and reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 400 mPa · s / 25 ° C., a pH of 7.4, and a number average molecular weight of 11,000.

Example 4
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 952.7 parts of water, 74.7 parts of isopropyl alcohol, 19.6 parts of dilauryl monomethylamine, 12.6 parts of triethylamine, and 40.4 parts of adipic acid dihydrazide were mixed and mixed uniformly. All of the urethane prepolymer was added to and reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 500 mPa · s / 25 ° C., a pH of 7.5, and a number average molecular weight of 11,000.

Example 5
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 1098.6 parts of water, 74.7 parts of isopropyl alcohol, 91.4 parts of polyoxyethylene-n-butylamine (number average molecular weight 513) and 40.4 parts of adipic acid dihydrazide were charged and mixed uniformly. While stirring, the entire amount of the urethane prepolymer was added and allowed to react at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 300 mPa · s / 25 ° C., a pH of 7.3, and a number average molecular weight of 12,000.

Comparative Example 1
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 910.8 parts of water, 74.7 parts of isopropyl alcohol, 18.0 parts of triethylamine, and 40.4 parts of adipic acid dihydrazide were charged and uniformly mixed. Then, the urethane prepolymer was added in its entirety with stirring. The mixture was reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 600 mPa · s / 25 ° C., a pH of 7.9, and a number average molecular weight of 10,000.

Comparative Example 2
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., (Number average molecular weight 2,000) 355.1 parts and isophorone diisocyanate 118.5 parts were charged and reacted at 85 ° C. for 5 hours to obtain 500.0 parts of an NCO group-containing urethane prepolymer. Was cooled to 70 ° C. In another stirring vessel, 1094.0 parts of water, 74.7 parts of isopropyl alcohol, 88.9 parts of polyoxyethylenepropylamine (number average molecular weight 499) and 40.4 parts of adipic acid dihydrazide were charged and mixed uniformly. The whole amount of the urethane prepolymer was added to the bottom and reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 400 mPa · s / 25 ° C., a pH of 7.2, and a number average molecular weight of 12,000.

Comparative Example 3
In a reaction vessel equipped with a stirrer, a thermometer, a cooling tube and a nitrogen gas introduction tube, 26.4 parts of dimethylolbutanoic acid, polypropylene glycol (trade name “Adeka Polyether P-2000” manufactured by Asahi Denka Kogyo Co., Ltd., Number average molecular weight 2,000) 230.6 parts, polyoxyethylene octadecylamine (number average molecular weight 709) 98.8 parts, isophorone diisocyanate 144.2 parts, charged at 85 ° C. for 5 hours, containing NCO group After obtaining 500.0 parts of urethane prepolymer, the system was cooled until the system temperature reached 70 ° C. In another stirring vessel, 923.5 parts of water, 74.7 parts of isopropyl alcohol, 18.0 parts of triethylamine, and 47.2 parts of adipic acid dihydrazide were charged and uniformly mixed. Then, the entire amount of the urethane prepolymer was added with stirring. The mixture was reacted at 50 ° C. for 3 hours while being dispersed. The polyurethane resin aqueous dispersion thus obtained had a resin solid content concentration of 35%, a viscosity of 700 mPa · s / 25 ° C., a pH of 7.8, and a number average molecular weight of 11,000.

  The following items were evaluated for each polyurethane resin aqueous dispersion obtained in Examples 1 to 5 and Comparative Examples 1 to 3. The results are shown in Table 1.

(Adhesion)
Each polyurethane resin aqueous dispersion is coated on the treated surfaces of a corona-treated polypropylene film (OPP), polyethylene terephthalate film (PET), and nylon film (NY) using a bar coater (No. 4). Then, it was dried for 1 minute with a heat gun (trade name “Pragjet PJ-206A”, manufactured by Ishizaki Electric Manufacturing Co., Ltd.) to obtain a polyurethane resin coating film. Next, an adhesive tape (trade name “Cellotape”, manufactured by Nichiban Co., Ltd.) was applied to the coated surface, and the remaining condition of the coating film was visually evaluated when peeled in the direction perpendicular to the coated surface.
○: More than 80% remained.
○ Δ: 60% or more and less than 80% remained.
Δ: 40% or more and less than 60% remained.
Δ ×: 20% or more and less than 40% remained.
X: Less than 20% remained.

As is clear from the results in Table 1 (Examples 1 and 3), it is clear that the effect of the present invention is not exhibited when the component (B) is used as a chain extender.

Claims (5)

The isocyanate group-terminated prepolymer (A) containing a carboxyl group obtained by reacting the polymer polyol (a-1) and the polyisocyanate compound (a-2) is represented by the general formula (1):

(R ¹ represents an alkyl group having 4 to 18 carbon atoms, A represents an oxyalkylene group having 2 carbon atoms, A may be different or the same, and x represents an integer of 1 to 10 . ) An aqueous polyurethane resin obtained by neutralization using an amine compound (B) which is an amine compound represented by formula (I) , dimethyl palmitylamine or dilauryl monomethylamine . The amine compound (B) is polyoxyethylene octadecylamine, polyoxyethylene dodecylamine, polyoxyethylene -n- butylamine, is at least one selected from the group consisting of dimethyl palmityl Amin Contact and dilauryl monomethylamine claims Item 12. An aqueous polyurethane resin according to Item 1. An aqueous polyurethane resin aqueous dispersion in which the aqueous polyurethane resin according to claim 1 or 2 is dispersed in water. A binder for printing ink comprising the aqueous polyurethane resin according to claim 1. A printing ink composition comprising the printing ink binder according to claim 4.