JP6136121B2 - Aqueous polyurethane resin and use thereof - Google Patents

Description

  The present invention relates to a polyurethane resin for an aqueous printing ink binder and an aqueous printing ink, and further to a laminate laminate. More specifically, not only water / alcohol solubility but also water solubility alone, water-based printing using polyurethane resin with excellent ink coating properties such as blocking resistance to various plastic film substrates The present invention relates to an ink, and further to a laminate laminate.

  Conventionally, many printing inks have been used as solvent-based inks, but conversion to water-based printing inks has been proposed as a means for solving the problems of environmental protection and legal regulations in recent years. Water-based printing inks have been widely used for printing on paper containers such as general wrapping paper and cardboard. However, in the field of printing on non-permeable plastic film base materials, mainly for packaging materials, there are still many problems compared to solvent-based printing inks.

  The quality of printing ink largely depends mainly on the binder resin which is the main component. In the case of solvent-based printing inks, polyurethane resins are widely used as the main binder resin in consideration of generalization and high performance. This is because a polyurethane resin can be freely designed from a hard and tough coating film to a soft and elastic coating film by appropriately selecting a polyisocyanate and a polymer polyol. Similarly, a water-based printing ink is considered to be suitable for general purpose and high performance, and a lot of water-based polyurethane resins have been researched and developed in recent years, but are still in the developing stage.

  Among the problems of water-based printing inks using polyurethane resins, the item that is considered to have the most significant difference from solvent-based printing inks is printability of printing inks. This printability is greatly affected by the solubility of the printing ink in the solvent. Therefore, studies have been made to improve the solubility in printing ink in a solvent, that is, the solubility in water-alcohol, but the printability of the aqueous printing ink is still insufficient.

  For example, Japanese Patent Application Laid-Open No. 2005-325190 proposes a water-based printing ink using a polyurethane emulsion composition, and studies are being made on improving adhesion to various plastic films and the like. However, since the polyurethane resin is an emulsion composition, the solubility in water is poor and the printability is insufficient.

  In JP-A-6-206972, studies have been made to increase the suitability of a laminate laminate for boiling and retorting by using a hydrazine residue. However, the solubility in water is poor.

JP 2005-325190 A JP-A-6-206972

  The object of the present invention is an aqueous printing ink that uses not only water-alcohol solubility but also water solubility alone, and water-based polyurethane resin with excellent ink blocking resistance to various plastic film substrates. It is to provide a printing ink, and also a laminate laminate.

  As a result of intensive studies in view of the above circumstances, the present inventors have used a polyurethane resin as an organic diamine containing an organic diamine having a hydroxyl group as a chain extender, an alkanolamine as a reaction terminator, and a polyurethane resin. By controlling the hydroxyl value of the polymer and the molar ratio of organic diamine to alkanolamine, water-alcohol solubility and water solubility are improved, and ink blocking resistance to various plastic film substrates is improved. The present inventors have found an excellent aqueous polyurethane resin and have reached the present invention.

That is, the first invention of the present invention is
Polyisocyanate (a);
A polyol (b) which is at least one selected from polyether polyol, polyester polyol, polycaprolactone polyol and polycarbonate polyol;
A urethane prepolymer having an isocyanate group at the end obtained by reacting a compound (c) having a carboxyl group and at least two active hydrogen-containing groups in the molecule;
An organic diamine (d) containing an organic diamine having a hydroxyl group as a chain extender;
Furthermore, a water-based printing ink using a water- based polyurethane resin obtained by reacting a monoamine alkanolamine (e) (excluding tertiary amine) as a reaction terminator,
The hydroxyl value of the aqueous polyurethane resin is 10.0 to 28.0 mgKOH / g
The ratio (d) / (e) of the number of moles of organic diamine (d) to the number of moles of alkanolamine (e) is 3.0 to 20.0.
The present invention relates to a water-based printing ink .

Furthermore, the second invention
The present invention relates to a laminate laminate obtained by printing a water-based printing ink according to the first invention on a substrate.

  INDUSTRIAL APPLICABILITY The present invention can provide a water-based printing ink using a water-based polyurethane resin having good re-solubility in water-alcohol and water alone, and good ink blocking resistance to various plastic film substrates, and a laminate laminate. It was.

  Hereinafter, the water-based polyurethane resin for the water-based printing ink binder will be described. The aqueous polyurethane resin of the present invention has an isocyanate group at the terminal obtained by reacting a polyisocyanate (a), a polymer polyol (b), and a compound (c) having a carboxyl group and at least two active hydrogen-containing groups in the molecule. Is obtained by reacting an organic diamine (d) containing an organic diamine having a hydroxyl group as a chain extender and an alkanolamine (e) as a reaction terminator.

  As the polyisocyanate (a) used in the aqueous polyurethane resin of the present invention, various known diisocyanates of aromatic, aliphatic or alicyclic can be used. For example, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3- Phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4- Trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate Isophorone diisocyanate, lysine diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, methylcyclohexane diisocyanate, m-tetramethylxylylene diisocyanate, and carboxyl groups of dimer acid were converted to isocyanate groups. Dimer isocyanate is a typical example. These can be used alone or in admixture of two or more. Isophorone diisocyanate is preferable in terms of reactivity and the like.

The polyol (b) in the present invention is at least one selected from polyether polyol, polyester polyol, polycaprolactone polyol, and polycarbonate polyol. These can be used alone or in admixture of two or more. More preferably, it is selected from polyether polyol and polyester polyol.
Examples of the polyether polyol in the present invention include polymers or copolymers such as methylene oxide, ethylene oxide, propylene oxide, and tetrahydrofuran. These can be used alone or in admixture of two or more. In particular, a polymer of ethylene oxide, that is, polyethylene glycol is preferable. When polyethylene glycol is used, the re-solubility in water-alcohol and water is good.

Examples of the polyester polyol in the present invention include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, pentanediol, 2-methyl-1,3-propanediol, and neopentyl glycol. 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propane Low molecular polyols such as diol, 1,4-butynediol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-cyclohexanedimethanol, diethylene glycol, polypropylene glycol, dipropylene glycol, and adipic acid , Phthalic acid, isophthalic acid, terephthalic acid , Maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, speric acid, azelaic acid, sebacic acid, trimellitic acid, pyromellitic acid and other polycarboxylic acids or their anhydrides A dehydration condensate or a polymer is mentioned. These can be used alone or in admixture of two or more.
The polycaprolactone polyol in the present invention is obtained by ring-opening polymerization of ε-caprolactone.

The polycarbonate diol in the present invention includes, for example, carbonate components such as alkylene carbonate, diallyl carbonate, dialkyl carbonate or phosgene, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, pentane. Diol, 2-methyl-1,3-propanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,9-nonanediol, 2-methyl-1,8- Octanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-butynediol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-cyclohexanedimethanol, diethylene glycol, Polypropylene Glycol, condensates of low molecular weight polyols such as dipropylene glycol. These can be used alone or in admixture of two or more.
Furthermore, three hydroxyl groups such as triethylene glycol, glycerin having two or more hydroxyl groups, trimethylolethane, trimethylolpropane, 1,2,4-butanetriol, 1,2,6-hexanetriol, sorbitol, pentaerythritol, etc. It is also possible to use the low molecular polyol having the above as a urethane monomer, and further to use it as a raw material for various polymer polyols.

  The active hydrogen-containing group in the present invention refers to a group having active hydrogen such as a hydroxyl group and an amino group that reacts with an isocyanate group.

  Examples of the compound (c) having a carboxyl group and at least two active hydrogen-containing groups in the molecule according to the present invention include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, and 2,2-dimethylolvaleric acid. And diamine-type amino acids such as glutamine, asparagine, lysine, diaminopropionic acid, ornithine, diaminobenzoic acid, and diaminobenzenesulfonic acid. These can be used alone or in admixture of two or more.

The hydroxyl value of the aqueous polyurethane resin of the present invention is calculated by converting the amount of hydroxyl group in 1 g of resin calculated by esterifying or acetylating the hydroxyl group in the resin and back titrating the remaining acid with an alkali into the number of mg of potassium hydroxide. The value obtained in accordance with JIS K0070.
Organic diamine that having a hydroxyl group used in the aqueous polyurethane resin (d) of the present invention are used as chain extenders. Examples thereof include 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine. These can be used alone or in admixture of two or more.

 Further, organic diamines having no hydroxyl group can be used in combination as a chain extender within the range of the prescribed hydroxyl value. Examples of the organic diamine having no hydroxyl group include ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, and dicyclohexylmethane-4. , 4′-diamine, and dimer diamine obtained by converting the carboxyl group of dimer acid into an amino group. These can be used alone or in admixture of two or more.

Alkanolamine (e), which is a monoamine used in the aqueous polyurethane resin of the present invention , is used as a reaction terminator. The alkanolamine of the present invention excludes tertiary amines. For example, monoethanolamine, diethanolamine , 2 -amino-2-methyl-1-propanol, 2-amino-2-ethyl-1,3-propanediol and the like can be mentioned. These can be used alone or in admixture of two or more. In particular, monoethanolamine is more preferable.

The hydroxyl value of the aqueous polyurethane resin in the present invention is 10.0 to 28.0 mgKOH / g. When the hydroxyl value is less than 10.0 mgKOH / g, the water-alcohol resolubility and water resolubility are poor, and when it is greater than 28.0 mgKOH / g, the blocking resistance is poor. More preferably, the hydroxyl value is 10.0 to 20.0 mgKOH / g.
The ratio (d) / (e) of the number of moles of the organic diamine (d) and the number of moles of the alkanolamine (e) in the present invention is 3.0 to 20.0. When the mole ratio is less than 3.0, the blocking resistance is poor, and when it is greater than 20.0, the re-solubility in water is poor. More preferably, it is 3.5-11.0.

  The acid value of the aqueous polyurethane resin in the present invention is preferably 25 to 45 mgKOH / g. The acid value is a value obtained by converting the acid amount in 1 g of the resin calculated by titrating the acid with an alkali into the number of mg of potassium hydroxide, according to JIS K0070. When the acid value is lower than 25 mg KOH / g, the water-alcohol re-solubility and water re-solubility, and the blocking resistance tend to be inferior. When the acid value is higher than 45 mg KOH / g, There is a tendency for adhesion to be low.

  The weight average molecular weight of the aqueous polyurethane resin of the present invention is preferably in the range of 5,000 to 100,000. When the weight average molecular weight is less than 5,000, the blocking resistance to various plastic film substrates tends to be inferior. When the weight average molecular weight exceeds 100,000, the viscosity of the resulting aqueous printing ink composition increases, and water-alcohol and water re-apply. There is a tendency for solubility to decrease.

  The aqueous polyurethane resin in the present invention can be obtained by an acetone method using an organic solvent which is inactive with respect to isocyanate and a hydrophilic, a solventless synthesis method using no solvent at all. In the present invention, an acetone method is used in which an organic solvent is used to lower the viscosity, and the synthesis reaction can be performed uniformly and smoothly.

  A urethane prepolymer having an isocyanate group at the terminal is obtained by reacting a polyisocyanate (a), a polymer polyol (b), and a compound (c) having a carboxyl group and at least two active hydrogen-containing groups in the molecule ( Hereinafter, the prepolymer reaction is preferably performed at 50 to 100 ° C. for 10 minutes to 10 hours. The end point of the reaction is judged by viscosity measurement, NCO peak by IR measurement, NCO% measurement by titration, and the like.

  A catalyst can also be used for the prepolymer reaction. As the catalyst that can be used, a known metal catalyst or amine catalyst can be used. Examples of the metal catalyst include dibutyltin dilaurate, tin octoate, dibutyltin di (2-ethylhexoate), lead 2-ethylhexoate, 2-ethylhexyl titanate, 2-ethylhexoate iron, 2- Examples thereof include ethylhexoate cobalt, zinc naphthenate, cobalt naphthenate, and tetra-n-butyltin. Examples of amine-based catalysts include tertiary amines such as tetramethylbutanediamine. These catalysts are used in the range of 0.001 to 1 mol% with respect to the polymer polyol.

  When the urethane prepolymer and the organic diamine are reacted (hereinafter, chain extension reaction), it is preferably performed at 30 to 80 ° C. for 10 minutes to 10 hours. The end point of the reaction is judged by viscosity measurement, NCO peak by IR measurement, amine value measurement by titration, and the like.

  In the present invention, an alkanolamine-derived hydroxyl group arranged at the end of the polymer chain is an important element for solving the problem. Therefore, the alkanolamine used as a reaction terminator uses an amino group as a reaction site and leaves a hydroxyl group, so that a tertiary amine having no active hydrogen is not used. Further, since the hydroxyl group of alkanolamine is present at the end of the polyurethane chain, the reaction terminator is added after the chain extension reaction is completed. At this time, it is preferably performed at 30 to 80 ° C. for 10 minutes to 2 hours.

  The basic compound for neutralizing the carboxyl group incorporated in the aqueous polyurethane resin of the present invention includes ammonia, monoethylamine, diethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, methyldiethanolamine, monoethanolamine Organic amines such as dimethylethanolamine, diethylethanolamine, morpholine, N-methylmorpholine, 2-amino-2-methyl-1-propanol; and inorganic alkalis such as sodium hydroxide and potassium hydroxide, 1 type or 2 types or more are used in combination, but from the viewpoint of water resistance of the printed matter, residual odor, etc., water-soluble and highly volatile compounds that are easily dissociated by heat are preferable, and ammonia is particularly preferable.

  Examples of the inert and hydrophilic organic solvent for isocyanate include ethers such as tetrahydrofuran and dioxane, esters such as ethyl acetate, ketones such as acetone, methyl ethyl ketone and cyclohexanone, dimethylformamide, and N-methylpyrrolidone. However, the water-based polyurethane is usually removed by distillation under reduced pressure (solvent removal), and in order to increase the drying speed even when it is used without solvent removal, a solvent having a boiling point lower than that of water is used. Use is preferred. In the case of removing the solvent, for example, water and a basic compound as a neutralizing agent are added to the reaction solution, and then the temperature is raised and the solvent is distilled off at a normal pressure or under a reduced pressure. .

  Examples of the colorant blended to have the functions required for the aqueous printing ink of the present invention include organic and inorganic pigments and dyes used in general inks, paints, and recording agents. . Organic pigments include azo, phthalocyanine, anthraquinone, perylene, perinone, quinacridone, thioindigo, dioxazine, isoindolinone, quinophthalone, azomethine azo, dictopyrrolopyrrole, isoindoline, etc. Pigments. Examples of the inorganic pigment include carbon black, titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, bengara, aluminum, mica (mica), and the like. From the viewpoints of cost and coloring power, it is preferable to use titanium oxide for white ink, carbon black for black ink, aluminum for silver ink, and mica for pearl ink.

  The colorant is preferably contained in an amount sufficient to ensure the density and coloring power of the ink, that is, in a proportion of 1 to 50% by weight based on the total weight of the ink. The colorants can be used alone or in combination of two or more.

  In order to stably disperse the pigment in the aqueous medium, the aqueous polyurethane resin of the present invention can be dispersed alone, but a dispersant can also be used in combination to disperse the pigment stably. As the dispersant, anionic, nonionic, cationic, amphoteric surfactants can be used. The dispersant is preferably contained in the ink in an amount of 0.05% by weight or more based on the total weight of the ink from the viewpoint of storage stability of the ink and 5% by weight or less from the viewpoint of the laminate strength, and more preferably 0%. .1 to 2% by weight.

  Examples of the resin used in combination with the aqueous printing ink of the present invention as needed include aqueous polyurethane resins other than the present invention, shellac, rosin-modified maleic acid resin, aqueous acrylic resin, aqueous polyester resin, and the like. The combined resins can be used alone or in admixture of two or more, as long as the object of the present invention is not impaired.

  The aqueous printing ink of the present invention can be produced by dissolving and / or dispersing a resin, a colorant and the like in an aqueous solution. Specifically, a pigment dispersion is prepared by dispersing a pigment in an aqueous solution using the polyurethane resin of the present invention, the combination resin, and the dispersant, and the resulting pigment dispersion is optionally mixed with waxes. An ink can be produced by blending other compounds such as an antifoaming agent, a thickener, and a curing agent.

  The particle size distribution of the pigment in the pigment dispersion is adjusted by appropriately adjusting the size of the grinding media of the disperser, the filling rate of the grinding media, the dispersion treatment time, the discharge speed of the pigment dispersion, the viscosity of the pigment dispersion, and the like. be able to. As a disperser, generally used, for example, a roller mill, a ball mill, a pebble mill, an attritor, a sand mill and the like can be used.

  In the case where bubbles or unexpectedly coarse particles are contained in the aqueous printing ink, it is preferably removed by filtration or the like in order to reduce the quality of the printed matter. A known filter can be used.

  The ink viscosity of the aqueous printing ink produced by the above method is in the range of 10 mPa · s or more from the viewpoint of preventing the pigment from settling and being appropriately dispersed, and 1000 mPa · s or less from the viewpoint of workability efficiency during ink production or printing. It is preferable that In addition, the said viscosity is a viscosity measured at 25 degreeC with the Tokimec B-type viscometer.

The viscosity of the aqueous printing ink can be adjusted by appropriately selecting the type and amount of raw materials used, for example, a polyurethane resin, a colorant, and an aqueous solution. The viscosity of the ink can also be adjusted by adjusting the particle size and particle size distribution of the pigment in the ink.
Since the polyurethane resin used in the aqueous printing ink of the present invention contains a hydroxyl group, it is possible to improve pigment dispersion and further improve the coating strength by using a crosslinking agent containing a silanol group or an isocyanate group in the printing ink. Can be raised more.

  The aqueous printing ink composition can be printed on a plastic film by a known gravure printing method, flexographic printing method, inkjet printing method or the like.

  When printing, it is diluted with an aqueous solution such as ethyl alcohol, isopropyl alcohol, normal propyl alcohol, and other organic solvents and water to a viscosity and concentration suitable for gravure printing and flexographic printing. , Alone or mixed and fed to each printing unit.

Examples of the plastic film include polyester, nylon, and polyolefin. In the case of a polyolefin film, a good printed matter can be obtained by using a surface-treated polyolefin film having a functional group such as a hydroxyl group or a carbonyl group.
The laminate laminate of the present invention is obtained by printing the water-based printing ink composition of the present invention on a plastic film and aging the laminated laminate product. The laminating method is as follows: 1) Extrusion laminating method in which a molten resin is laminated after applying an anchor coating agent on the printed surface of the obtained printed matter, if necessary. 2) After applying an adhesive, if necessary. And a dry laminating method in which a plastic film is laminated by drying. As the molten resin, low density polyethylene, polypropylene, ethylene-vinyl acetate copolymer and the like can be used, and as the adhesive, imine, isocyanate, polybutadiene, titanate and the like can be mentioned.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these Examples. In the present invention, “parts” and “%” represent “parts by weight” and “% by weight” unless otherwise noted. The weight average molecular weight was obtained as a polystyrene-converted molecular weight by measuring the molecular weight distribution using a GPC (gel permeation chromatography) apparatus.

[Synthesis Example 1]
While introducing nitrogen gas in a reactor equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen gas introduction tube, 147.07 parts of polytetramethylene glycol having a number average molecular weight of 2000, and polyethylene glycol 25 having a number average molecular weight of 2000 .95 parts, 21.50 parts of 2,2-dimethylolpropionic acid and 87.77 parts of isophorone diisocyanate were subjected to boiling reaction in 200 parts of methyl ethyl ketone for 6 hours to form a terminal isocyanate prepolymer, and then cooled to 40 ° C. 100 parts of acetone was added to obtain a solvent solution of the terminal isocyanate prepolymer. Next, to the mixture of 6.17 parts of 2-hydroxyethylethylenediamine, 10.09 parts of isophoronediamine and 350 parts of acetone, 580.87 parts of the obtained terminal isocyanate prepolymer solution was gradually added at room temperature. The mixture was reacted at 50 ° C. for 3 hours, then 1.45 parts of monoethanolamine and 50 parts of acetone were gradually added at room temperature and reacted at 50 ° C. for 1 hour to obtain a solvent-type polyurethane resin solution. Next, 9.73 parts of 28% ammonia water and 700 parts of deionized water are gradually added to the solvent-type polyurethane resin solution to neutralize the solution, and the whole amount of methyl ethyl ketone and acetone is distilled under azeotropy. After leaving, the viscosity was adjusted by adding water to obtain a polyurethane resin PU01 having an acid value of 30 mgKOH / g, a solid content of 30%, a viscosity of 800 mPa · s, and a weight average molecular weight of 31,000.

[Synthesis Examples 2 to 21]
Polyurethane resins (PU02 to PU21) were obtained in the same manner as in Synthesis Example 1 with the charging ratios in Table 1 and Table 2. The following raw materials were used for the synthesis.
PTG2000: polytetramethylene glycol (number average molecular weight 2000)
PMPA2000: poly (3-methyl-1,5-pentaneadipate) diol (number average molecular weight 2000)
PCL2000: polycaprolactone diol (number average molecular weight 2000)
PC2000: Polycarbonatediol (number average molecular weight 2000)
PEG2000: polyethylene glycol (number average molecular weight 2000)
DMPA: 2,2-dimethylolpropionic acid IPDI: isophorone diisocyanate AEA: 2-hydroxyethylethylenediamine IPDA: isophoronediamine H12MDA: dicyclohexylmethane-4,4′-diamine TMDA: trimethylhexamethylenediamine MEA: monoethanolamine DEA: diethanolamine MEK: Methyl ethyl ketone

[Example 1]
15.00 parts of copper phthalocyanine indigo, 30.00 parts of polyurethane resin (PU01), 0.10 parts of antifoaming agent, 5.00 parts of isopropyl alcohol, and 19.90 parts of water were stirred and mixed in a sand mill, and then polyurethane 20.00 parts of a resin solution (PU01), 5.00 parts of isopropyl alcohol, and 10.00 parts of water were stirred and mixed to obtain a deep blue ink (C01). Furthermore, for this indigo color printing ink, using a mixed solvent of water / isopropyl alcohol mixed solvent (weight ratio 1/1), adjusted to 16 seconds with Zahn Cup # 3 (manufactured by Hokensha) for evaluation. Dilute printing ink.
[Examples 2 to 14] [Comparative Examples 1 to 7]
Indigo printing inks (C02-16 and C17-32) were obtained by the same operation as in Example 1. In addition, the polyurethane resin used for each printing ink is as Table 2. Moreover, the diluted printing ink for evaluation was also obtained by the same operation as Example 1.
The evaluation method and criteria of re-solubility in water-alcohol, re-solubility in water, and blocking resistance are described below.

[Re-solubility in water-alcohol]
After the diluted printing ink was applied to the ballad plate and allowed to air dry, 25 ml of a diluting solvent (water / isopropyl alcohol mixed solvent (weight ratio 70/30)) was poured to visually determine the degree of dissolution of the printing ink film.
A: All dissolved.
○: Slight unresolved residue was observed.
○ Δ: Undissolved residue with an area of less than 10% was observed.
Δ: Undissolved area of 10% or more and less than 30% was observed. More practical than that.
Δ ×: An undissolved portion having an area of 30% or more was observed.
X: Almost not dissolved.

[Re-solubility in water]
The diluted printing ink was applied to the ballad plate in the same procedure as the evaluation of re-solubility in water-alcohol, and after 30 seconds, 25 ml of water was sprinkled to visually determine the degree of dissolution of the printing ink film.
A: All dissolved.
○: Slight unresolved residue was observed.
○ Δ: Undissolved residue with an area of less than 10% was observed.
Δ: Undissolved area of 10% or more and less than 30% was observed. More practical than that.
Δ ×: An undissolved portion having an area of 30% or more was observed.
X: Almost not dissolved.

[Blocking resistance]
The diluted printing ink was printed on a treated polypropylene film (hereinafter referred to as OPP, “Pyrene P2161” manufactured by Toyobo Co., Ltd., thickness 20 μ) with a gravure printing machine (plate depth 25 μm) to obtain a print sample. Using this printed sample, the sample is sampled to 4 cm x 4 cm, the unprinted surface of the unprinted film of the same size as the printed surface of this sample is combined, and the sample is peeled off by applying 10 kgf at 40 ° C for 12 hours. The ink was removed and the resistance was observed.
A: Ink transfer from the printed matter was not observed at all, and there was no resistance when peeled.
○: No transfer of ink was observed from the printed matter, but there was a feeling of resistance during peeling.
◯: Ink transfer from the printed matter was slightly observed, and the area was less than 5%.
Δ: Ink transfer was observed from the printed matter, and the area was 5% or more and less than 10%.
More practical than that.
Δ ×: Ink transfer from the printed material was observed in an area of 10% or more and less than 50%.
X: Ink transfer from the printed matter was observed in an area of 50% or more.
The evaluation results are summarized in Tables 3 and 4. The water-based printing ink compositions of Examples 1 to 14 are water-based printing inks having excellent water-alcohol and water re-solubility and blocking resistance as compared with the water-based printing ink compositions of Comparative Examples 1 to 7. Can be provided.

Claims (2)

Polyisocyanate (a);
A polyol (b) which is at least one selected from polyether polyol, polyester polyol, polycaprolactone polyol and polycarbonate polyol;
A urethane prepolymer having an isocyanate group at the end obtained by reacting a compound (c) having a carboxyl group and at least two active hydrogen-containing groups in the molecule;
An organic diamine (d) containing an organic diamine having a hydroxyl group as a chain extender;
Furthermore, a water-based printing ink using a water- based polyurethane resin obtained by reacting a monoamine alkanolamine (e) (excluding tertiary amine) as a reaction terminator,
The hydroxyl value of the aqueous polyurethane resin is 10.0 to 28.0 mgKOH / g
The ratio (d) / (e) of the number of moles of organic diamine (d) to the number of moles of alkanolamine (e) is 3.0 to 20.0.
A water-based printing ink characterized by
Laminate laminate formed by printing an aqueous printing ink according to claim 1, wherein the substrate.