JP2013227465A - Polyurethane resin composition for printing ink binder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing ink composition using a polyurethane resin composition compatibilizing printability such as excellent fogging properties and printing properties such as excellent antiblocking property, adhesiveness, alcohol bleeding resistance or the like, in an ester/alcohol solvent system corresponding to exclusion of aromatic organic solvent such as toluene and xylene and ketone-based organic solvent such as methylethylketone and methylisobutylketone.SOLUTION: There is provided a polyurethane resin composition comprising: a polyurethane resin obtained by reacting an organic diamine and an alkanol amine with a urethane prepolymer that is made by reacting a polyisocyanate including tolylene diisocyanate, with a high-molecular polyol and that has an isocyanate group at a terminal thereof, wherein [NCO(total)]/[OH] and [NCO(TDI)]/[OH], the hydroxyl value of the polyurethane resin, and the ratio between the organic diamine and the alkanolamine are controlled, and a mixed solvent including an ester-based solvent and an alcohol.

Description

  The present invention relates to a polyurethane resin composition for printing ink binders and a printing ink composition, and more particularly to an ester / alcohol solvent based printing ink composition using a polyurethane resin composition useful for various plastic films.

  Conventionally, as solvents used in printing inks, aromatic solvents such as toluene and xylene having relatively high dissolving power and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone have been used. In recent years, however, the printing ink industry has been required to consider environmental issues from the viewpoint of environmental protection and legal regulations on a global scale. Ester / alcohol solvents that eliminate these aromatic and ketone solvents Printing inks using the system are desired. Therefore, research and development of printing inks based on ester / alcohol solvents has been carried out, but ester / alcohol solvent systems have lower solvency compared to aromatic and ketone solvents, resulting in poor printability, Due to the work to increase the dissolving power in the ester / alcohol solvent, other physical properties such as alcohol bleed resistance and blocking resistance are still inferior.

  For example, in JP-A-9-316156, a polyurethane resin composition and a printing ink composition using diphenylmethane diisocyanate have excellent adhesion to various plastic films, but are required to be excluded in order to ensure printability. There are still studies involving methyl ethyl ketone. Moreover, since the [NCO] / [OH] ratio is low, there is also a problem in blocking resistance.

  Japanese Patent Laid-Open No. 2003-221539 discloses that an ink is assembled in an ester / alcohol solvent system, and studies have been made to increase the solubility in the ester / alcohol solvent system. However, a hydroxycarboxylic acid is added to the ink. Therefore, residual solvent, water resistance and alcohol bleed resistance are inferior.

JP 9-316156 A JP 2003-221539 A

  In the ester / alcohol solvent system corresponding to the elimination of aromatic organic solvents such as toluene and xylene and ketone organic solvents such as methyl ethyl ketone and methyl isobutyl ketone, the present invention ensures excellent printability such as plate fogging, It is another object of the present invention to provide a printing ink composition having excellent adhesion to various plastic films, blocking resistance, alcohol bleed resistance, and printed physical properties such as laminate physical properties.

  As a result of intensive studies in view of the above circumstances, the present inventors have used a polyisocyanate containing tolylene diisocyanate as an isocyanate, and a polyurethane resin using an alkanolamine as a reaction terminator and controlling the synthesis parameters. The present invention has found that it is possible to design a printing ink composition using a polyurethane resin composition that achieves both excellent printability and print properties in an ester / alcohol solvent system having a relatively weak dissolving power. It came to.

That is, the first invention of the present invention is a polyurethane resin obtained by reacting a urethane prepolymer having an isocyanate group at the terminal obtained by reacting a polyisocyanate containing tolylene diisocyanate and a polymer polyol with an organic diamine and an alkanolamine. ,
A polyurethane resin composition comprising a mixed solvent,
It is related with the polyurethane resin composition characterized by being the following (A)-(E).
(A) The molar ratio [NCO (total)] / [OH] in the reaction of all isocyanate groups of the polyisocyanate and hydroxyl groups of the polymer polyol is 1.8 to 2.3.
(B) The molar ratio [NCO (TDI)] / [OH] in the reaction between the isocyanate group of tolylene diisocyanate and the hydroxyl group of the polymer polyol is 1.0 to 2.1.
(C) The hydroxyl value of the polyurethane resin is 1.0 to 10.0 mgKOH / g.
(D) The molar ratio d1 / d2 between the number of moles d1 of the organic diamine and the number of moles d2 of the alkanolamine is 3-25.
(E) The mixed solvent includes an ester solvent and an alcohol solvent.

Next, in the second invention, the polymer polyol comprises a polyester diol and a polyether diol,
2. The polyurethane resin composition according to claim 1, wherein the polyester polyol is 20 to 80% by weight and the polyether diol is 80 to 20% by weight in the polymer polyol.

  Furthermore, the third invention relates to a printing ink composition comprising the polyurethane resin composition described in the first invention or the second invention.

  The present invention makes it possible to provide a printing ink composition using a polyurethane resin composition that ensures excellent printability in an ester / alcohol solvent system and possesses excellent print properties.

  Hereinafter, the polyurethane resin composition for a printing ink binder will be described. A polyurethane resin is obtained by reacting a polyisocyanate containing tolylene diisocyanate and a high molecular polyol with a urethane prepolymer having an isocyanate group at the terminal and an organic diamine as a chain extender and an alkanolamine as a reaction terminator. .

  In polyurethane resins used as printing ink binders, when considering the compatibility between the solubility in ester / alcohol solvents and various printed physical properties for various plastic films, the important factors are the hard segments of urethane bonds and urea bonds. Is a polyisocyanate.

  In the present invention, the polyisocyanate used in the polyurethane resin contains tolylene diisocyanate and may be expressed as TDI. Tolylene diisocyanate is preferably 2,4-tolylene diisocyanate or 2,6-tolylene diisocyanate, and 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate may be mixed and used.

  Since tolylene diisocyanate is an aromatic isocyanate having one aromatic ring in the molecule, it has higher resistance to alcohol than aliphatic isocyanates and alicyclic isocyanates. On the other hand, as compared to diphenylmethane diisocyanate, which is an aromatic isocyanate having two aromatic rings, tolylene diisocyanate has a single aromatic ring and therefore has a higher solubility in an ester / alcohol solvent system. Therefore, it can be said that tolylene diisocyanate is a polyisocyanate that easily balances printing suitability such as plate fog and alcohol bleed resistance in an ester / alcohol solvent-based printing ink composition.

  In the present invention, when synthesizing a urethane prepolymer having an isocyanate group at the terminal obtained by reacting a polyisocyanate containing tolylene diisocyanate and a polymer polyol, the molar ratio of all isocyanate groups of the polyisocyanate and the hydroxyl group of the polymer polyol. [NCO (all)] / [OH] is in the range of 1.8 to 2.3. If [NCO (all)] / [OH] is less than 1.8, the number of hard segment bonds decreases, so that the blocking resistance and alcohol bleed resistance are inferior. If it is greater than 2.3, the plate fogging property is inferior. Adhesiveness and EL laminate strength are inferior because the number of segment bonds is too large.

  In the present invention, [NCO (TDI)] / [OH], which is a molar ratio in the reaction between the isocyanate group of tolylene diisocyanate and the hydroxyl group of the polymer polyol, is in the range of 1.0 to 2.1. In general, an aromatic isocyanate has a higher reaction rate with a hydroxyl group or an amino group than an aliphatic isocyanate or an alicyclic isocyanate. Therefore, when [NCO (TDI)] / [OH] is greater than 2.1, the reaction rate is too high to synthesize a uniform polyurethane resin, and further, the plate has a high concentration of aromatic rings in the molecule. Poor fogging property. Further, when [NCO (TDI)] / [OH] is smaller than 1.0, the alcohol bleeding resistance is inferior.

  In addition to the tolylene diisocyanate, another polyisocyanate may be used in combination as long as it satisfies the above [NCO (all)] / [OH] and [NCO (TDI)] / [OH]. Examples of other polyisocyanates include various known aliphatic isocyanates and alicyclic isocyanates that are generally used in the production of polyurethane resins. For example, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dimaryl diisocyanate, Examples thereof include dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, and dimerized isocyanate obtained by converting a carboxyl group of dimer acid into an isocyanate group. In the present invention, among other polyisocyanates, isophorone diisocyanate is preferred from the viewpoint of the reaction rate of the isocyanate group and various physical properties.

  Furthermore, the range satisfying the above [NCO (all)] / [OH] and [NCO (TDI)] / [OH], and 90 to 100% in the number of moles of all isocyanate groups is from tolylene diisocyanate. When the content is 10 to 0% from isophorone diisocyanate, the alcohol bleeding resistance is particularly excellent. Similarly, when 50 to 75% of the total number of isocyanate groups is from tolylene diisocyanate and 50 to 25% is from isophorone diisocyanate, 35% or more of the solvent contained in the printing ink composition is alcohol. It is particularly excellent in plate fog when it becomes a solvent. The details of the mixed solvent contained in the printing ink composition will be described later.

  Furthermore, the hydroxyl value of the polyurethane resin is an important factor for balancing printing suitability such as plate fog in an ester / alcohol solvent system and alcohol bleed resistance. The hydroxyl value of the polyurethane resin in the present invention is 1.0 to 10.0 mgKOH / g. When the hydroxyl value is less than 1.0 mgKOH / g, the adhesiveness and EL laminate strength are inferior, and the solubility is remarkably deteriorated, so that the plate fog is inferior. When the hydroxyl value is greater than 10.0 mgKOH / g, the alcohol bleed resistance is poor.

  The organic diamine as a chain extender in the present invention is ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, dicyclohexylmethane-4,4′-diamine, etc., 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyrroleethylenediamine, di-2-hydroxypyrroleethylenediamine, di-2 -Amines having a hydroxyl group in the molecule such as hydroxypropylethylenediamine can also be used. These chain extenders can be used alone or in admixture of two or more, and isophoronediamine is particularly preferred.

  In the present invention, the molar ratio d1 / d2 between the number of moles d1 of the organic diamine of the polyurethane resin and the number of moles d2 of the alkanolamine is 3-25. When d1 / d2 is smaller than 3, the alcohol bleed resistance is inferior, and the weight average molecular weight of the polyurethane resin is reduced, so that the blocking resistance is remarkably deteriorated. When d1 / d2 is larger than 25, the adhesiveness and EL laminate strength are inferior, and the solubility is also greatly deteriorated, so that the plate fogging property is inferior.

  In addition, when the usage-amount of alkanolamine which is a reaction terminator increases, the weight average molecular weight of the polyurethane resin obtained will become low. Further, since the alkanolamine contains a hydroxyl group, the hydroxyl value increases as the amount of alkanolamine used increases. Examples of the alkanolamine include monoethanolamine and diethanolamine. These can be used alone or in admixture of two or more, and monoethanolamine is particularly preferred.

  Various known polyester polyols, polyether polyols, and the like can be used as the polymer polyol, and one or more of them may be used in combination. Examples of the polyester polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2methyl-1,3-propanediol, 2ethyl-2butyl-1,3propanediol, and 1,3-butane. Diol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene Saturated or unsaturated low molecular weight polyols such as glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, and pentaerythritol Kind , 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 Polyester polyols obtained by dehydration condensation or polymerization of these polyhydric carboxylic acids or their anhydrides, cyclic ester compounds such as polycaprolactone, polyvalerolactone, poly (β-methyl-γ-valerolactone), etc. And polyester polyols obtained by ring-opening polymerization of lactones. Examples of polyether polyols include polymers or copolymers such as methylene oxide, ethylene oxide, propylene oxide, and tetrahydrofuran. Of polyester polyols and polyether polyols, those having a branched structure are particularly preferred.

  The polymer polyol used for the polyurethane resin in the present invention is a polyester diol and a polyether diol, and the polyester diol in the polymer polyol is preferably in the range of 20 to 80% by weight and the polyether diol in the range of 80 to 20% by weight. When the polyester diol is more than 80% by weight, the plate fogging tendency tends to be deteriorated, and when the polyether diol is more than 80% by weight, the blocking resistance tends to be inferior.

  The amine value of the polyurethane resin in the present invention is 2.0 to 7.0 mgKOH / g, more preferably 3.0 to 6.0 mgKOH / g. If the amine value is less than 2.0 mgKOH / g, the plate fogging property, adhesiveness and EL laminate strength tend to be inferior, and if it is more than 7.0 mgKOH / g, the blocking resistance tends to be inferior.

  The weight average molecular weight of the polyurethane resin in the present invention is 10,000 to 70,000, more preferably 15,000 to 60,000. When the weight average molecular weight is less than 10,000, the blocking resistance tends to be inferior, and the heat resistance deteriorates, so the EL laminate strength tends to be inferior. When the weight average molecular weight is more than 70,000, the plate fogging property, adhesiveness and EL laminate strength tend to be inferior.

  In the method of synthesizing a polyurethane resin in the present invention, a polyisocyanate containing a polymer polyol and tolylene diisocyanate is used, if necessary, using an inert solvent for the isocyanate group, and if necessary, using a urethanization catalyst. A polyurethane resin in which a prepolymer having an isocyanate group at the terminal is produced by reacting at a temperature of ˜100 ° C., and then this prepolymer is reacted with an organic diamine as a chain extender and an alkanolamine as a reaction terminator at 10˜80 ° Can be produced from a prepolymer method.

  The solvent used in the polyurethane resin composition of the present invention includes a mixed solvent of an ester solvent and an alcohol solvent. Examples of ester solvents include ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and alcohol solvents include methanol, ethanol, n-propanol, isopropanol, It is preferable to use a known solvent such as an alcohol solvent such as n-butanol, propylene glycol monoethyl ether, propylene glycol monomethyl ether.

  A catalyst can also be used for the urethanization reaction. Examples of catalysts that can be used include tertiary amine catalysts such as triethylamine and dimethylaniline; metal catalysts such as tin and zinc. These catalysts are usually used in the range of 0.001 to 1 mol% with respect to the polyol.

  The chain extender may be used together with the alkanolamine, which is a reaction terminator, and the organic diamine, which is a chain extender. May be added to the reaction to stop the reaction.

  In the printing ink composition of the present invention, an inorganic colorant and an organic colorant can be used as the colorant. As the white colorant, titanium oxide, which is an inorganic colorant, is used, but it is more preferable that the pigment surface is basic. In addition to the white colorant, pigments such as carbon black, aluminum, mica (mica) and the like can be used as the inorganic colorant. Aluminum is in the form of powder or paste, but is preferably used in the form of paste from the viewpoint of handling and safety, and whether to use leafing or non-leafing is appropriately selected from the viewpoint of brightness and concentration. On the other hand, examples of organic colorants include organic, pigments, and dyes used in general inks, paints, and recording agents. Examples thereof include azo, phthalocyanine, anthraquinone, perylene, perinone, quinacridone, thioindigo, dioxazine, isoindolinone, quinophthalone, azomethine azo, dictopyrrolopyrrole, and isoindoline.

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

  The printing ink composition of the present invention can be produced by dissolving and / or dispersing a resin, a colorant and the like in an organic solvent. Specifically, the polyurethane resin composition of the present invention is manufactured by dispersing the pigment in the polyurethane resin composition of the present invention and, if necessary, other compounds and the like in an organic solvent. An ink can be produced by blending a product, an organic solvent, and other compounds as required.

  In order to stably disperse the pigment in the organic solvent, the polyurethane resin in the present invention can be dispersed alone, but a dispersant can also be used in combination in order 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 the storage stability of the ink and 5% by weight or less from the viewpoint of the suitability for lamination. Furthermore, it is more preferable that it is contained in the range of 0.1 to 2% by weight.

  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 the 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.

  The solvent used in the printing ink composition of the present invention also includes a mixed solvent of an ester solvent and an alcohol solvent, like the polyurethane resin composition. Examples of ester solvents include ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and alcohol solvents include methanol, ethanol, n-propanol, isopropanol, It is preferable to use a known solvent such as an alcohol solvent such as n-butanol, propylene glycol monoethyl ether, propylene glycol monomethyl ether.

  In the case where bubbles or unexpectedly large particles are included in the ink, it is preferably removed by filtration or the like in order to reduce the quality of the printed matter. A conventionally well-known filter can be used.

  The viscosity of the 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. Is preferred. In addition, the said viscosity is a viscosity measured at 25 degreeC with the Tokimec B-type viscometer.

  The printing ink composition in the present invention can be used in known printing methods such as gravure printing and flexographic printing. For example, it is diluted with a diluent solvent to a viscosity and concentration suitable for gravure printing, and is supplied to each printing unit alone or mixed. Gravure printing is preferable.

  As a substrate to which the printing ink composition of the present invention can be applied, polyolefins such as polyethylene and polypropylene, polyethylene terephthalate, polycarbonate, polyester such as polylactic acid, polystyrene resins such as polystyrene, AS resin, and ABS resin, nylon, polyamide, Polyvinyl chloride, polyvinylidene chloride, cellophane, paper, aluminum, etc., or a film or sheet made of a composite material of these, is applied using the printing method described above, dried by oven drying, and fixed. By doing so, a printed matter can be obtained. The base material may be subjected to a metal oxide or the like on its surface by a vapor deposition coating treatment and / or a coating treatment such as polyvinyl alcohol, and may further be subjected to a surface treatment such as a corona treatment.

  If the printed matter obtained by printing the printing ink composition of the present invention is subjected to laminating and aging, a laminate laminate is obtained. 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 material, if necessary. 2) After applying an adhesive, it is dried if necessary. Examples include a dry laminating method in which plastic films are laminated. 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 hydroxyl value was acetylated with an excess of an acetylating reagent and the amount of hydroxyl group in 1 g of resin calculated by back titrating the remaining acid with alkali was converted to mg of potassium hydroxide. The value is a value obtained according to JIS K0070. The amine value is the number of mg of potassium hydroxide equivalent to the equivalent amount of hydrochloric acid required to neutralize the amino group contained in 1 g of resin. The acid value is the number of mg of potassium hydroxide required to neutralize the acid group contained in 1 g of resin, and the measurement method may be a known method, generally according to JIS K0070 (1996). Done. The molecular weight was determined as a polystyrene-converted molecular weight by measuring the molecular weight distribution using a GPC (gel permeation chromatography) apparatus. The method for measuring the amine value is as follows.

[Method for measuring amine value]
Weigh 0.5-2 g of sample accurately. (Sample amount: Sg) 30 mL of neutral ethanol (BDG neutral) is added to a precisely weighed sample and dissolved. The obtained solution is titrated with a 0.2 mol / L ethanolic hydrochloric acid solution (titer: f). The point at which the color of the solution changed from green to yellow was taken as the end point, and the amine value was determined by the following (Formula 1) using the titration amount (AmL) at this time.

Formula 1
Amine value = (A × f × 0.2 × 56.108) / S [mgKOH / g]

[Synthesis Example 1]
In a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen gas introduction tube, PPA2000 (hydroxyl value 56.1 mgKOH / g) with a molecular weight of 2000. 111.99 parts, PPG1000 with a molecular weight of 1000 (hydroxyl value 112.2 mgKOH) / G) 111.99 parts, 52.65 parts of tolylene diisocyanate, 0.03 part of tin (II) 2-ethylhexanoate, and 82.5 parts of ethyl acetate were allowed to react at 90 ° C. for 3 hours under a nitrogen stream. 359.16 parts of a terminal isocyanate prepolymer solution were obtained. Next, 359.16 parts of the solvent solution of the resulting terminal isocyanate prepolymer was mixed at room temperature with 21.74 parts of isophoronediamine, 1.64 parts of monoethanolamine, 290 parts of isopropyl alcohol, and 327.47 parts of ethyl acetate. The mixture was gradually added and then reacted at 50 ° C. for 1 hour to obtain a polyurethane resin composition (PU01) having a solid content of 30.0%, a weight average molecular weight of 30000, and an amine value of 4.0 mgKOH / g.

[Synthesis Examples 2 to 24]
A polyurethane resin composition (PU02 to PU24) was 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.
PPA2000: poly (1,2-propylene adipate) diol (number average molecular weight 2000)
NPG2000: poly (neopentyl adipate) diol (number average molecular weight 2000)
PMPA2000: poly (3-methyl-1,5-pentaneadipate) diol (number average molecular weight 2000)
PPG1000: poly (1,2-propylene glycol) (number average molecular weight 1000)
TDI: Tolylene diisocyanate IPDI: Isophorone diisocyanate MDI: Diphenylmethane diisocyanate IPDA: Isophoronediamine MEA: Monoethanolamine DEA: Diethanolamine DBA: Di-n-butylamine IPA: Isopropyl alcohol

[Example 1]
30.00 parts of titanium oxide (TITONE R45M manufactured by Sakai Chemical Co., Ltd.), 10.00 parts of polyurethane resin composition (PU01), 10.00 parts of ethyl acetate / isopropyl alcohol mixed solvent (weight ratio 70/30) were stirred and mixed in a sand mill. After kneading, 40.00 parts of polyurethane resin composition (PU01) and 10.00 parts of ethyl acetate / isopropyl alcohol mixed solvent (weight ratio 70/30) were mixed by stirring to obtain a white printing ink composition (W01). It was. Further, 100.00 parts of this white printing ink composition was diluted by 40. respectively with a dilution solvent 1 of ethyl acetate / isopropyl alcohol = 85/15 or a dilution solvent 2 of ethyl acetate / isopropyl alcohol = 50/50 by weight ratio. 00 parts were mixed to obtain white diluted printing ink 1 and white diluted printing ink 2 for evaluation.

[Examples 2 to 16] [Comparative Examples 1 to 8]
White printing ink compositions (W02 to 16 and W17 to 24) were obtained by the same operation as in Example 1. In addition, the polyurethane resin composition used for each printing ink composition is as Table 3 and Table 4. Further, by the same operation as in Example 1, 100.00 parts of the obtained white printing ink composition was diluted with a diluent 1 having a weight ratio of ethyl acetate / isopropyl alcohol = 85/15, or ethyl acetate / isopropyl alcohol = 50. 40.00 parts each of / 50 dilution solvent 2 was mixed to obtain white diluted printing ink 1 and white diluted printing ink 2 for evaluation.

[Plate fog]
An NBR (nitrile butadiene rubber) rubber hardness 80Hs impression cylinder, a blade thickness of 60 μm (base material thickness 40 μm, one side ceramic layer thickness 10 μm), a chrome hardness 1050 Hv made by Toyo Prepress Co., Ltd. The white diluted printing ink 1 or the white diluted printing ink 2 is set on a gravure printing machine manufactured by Fuji Machine Industry Co., Ltd. with an electronic engraving plate (stylus angle 120 degrees, 200 lines / inch), doctor pressure 2 kg / cm 2, 100 m / min. After idling at a rotational speed for 60 minutes, on a corona-treated surface of a single-sided corona-treated OPP film "Pyrene P-2161 (manufactured by Toyobo Co., Ltd.)" It was dried with hot air to obtain a printed matter. This printed matter was pasted on black paper, and the amount of ink attached to the blank portion (non-image area) was visually evaluated according to the following criteria.
A: No ink transfer was observed in the non-image area.
○: Slight ink transfer was observed in the non-image area.
○ Δ: Ink transfer was observed in a small area of the non-image area. More practical than that.
Δ: Ink transfer was observed in a large area of the non-image area.
X: Ink transfer was observed over the entire non-image area.

[Blocking resistance]
The white diluted printing ink 1 was printed on a corona-treated OPP film (Taiko FOR-Futamura # 20) by a gravure proofing machine equipped with a gravure plate having a plate depth of 35 μm and dried at 40 to 50 ° C. to obtain a printed matter. This printed matter was sampled to 4 cm × 4 cm, and the unprinted surface of the unprinted film having the same size as the printed surface of this sample was combined and pressurized at 50 ° C. for 12 hours and 10 kgf, and the sample was peeled off. 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 was observed from the printed matter, but the area was 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.

[Adhesiveness]
A cellophane tape (made by Nichiban, width 12 mm) is affixed to the printed matter obtained in the blocking resistance test and rubbed strongly with the thumb 5 times. Examined.
A: No peeling of ink was observed even when pulled apart slowly or suddenly.
○: Ink peeling is not observed at all even if pulled slowly,
When peeled off rapidly, ink peeling was observed in an area of less than 20%. More practical than that.
△: Ink peeling is not observed even if pulled slowly,
When peeled off rapidly, ink peeling was observed in an area of 20% or more.
Δ ×: Ink peeling with an area of up to about 50% was observed even when slowly separated.
X: Most ink peeling was recognized even if it pulled away slowly.

[Alcohol bleed resistance]
The white diluted printing ink 1 is printed on a corona-treated OPP film (Taiko FOR Futamura # 20) using a gravure proofing machine equipped with a 35 μm gravure printing plate, dried at 40-50 ° C., and then coated with isopropyl alcohol in-line. After drying at 40 to 50 ° C., the appearance such as bleed marks was observed.
A: There was no appearance defect on the printed matter.
○: Some unevenness was observed in the printed matter. More practical than that.
Δ: A thin bleed mark was observed on the printed matter.
X: Bleed marks were clearly observed on the printed matter.

[EL laminate strength]
Polypropylene (hereinafter referred to as OPP) film “Pyrene P-2161 (manufactured by Toyobo Co., Ltd.)” having a thickness of 20 μm by single-sided corona treatment under the printing conditions of the plate fog test, and polyethylene terephthalate (hereinafter “PET”) film having a thickness of 12 μm by single-sided corona treatment A printed material based on “Toyobo Ester Film E5100 (Toyobo Co., Ltd.)” was obtained, and a polyethyleneimine anchor coating agent “Olivein EL-420” (trade name, manufactured by Toyo Morton Co., Ltd.) was applied and applied. The melt temperature of low density polyethylene “Novatech LC600” (trade name, manufactured by Nippon Polychem Co., Ltd.) as a sealant was extruded on the surface at 315 ° C. to obtain a laminated product. The melting temperature of the low density polyethylene was measured with a contact thermometer (HL-100, manufactured by Anritsu Keiki Co., Ltd.) as the temperature immediately below the T die of the extrusion laminating machine. The ink part in the laminated product was cut at a width of 15 mm and peeled between the ink surface and the molten resin layer, and the peel strength was measured with an Intesco 2.01 million tensile tester. Note that the practical level is 1.0 N / 15 mm or more for the OPP / imine configuration and 1.5 N / 15 mm or more for the PET / imine configuration.

  The evaluation results are summarized in Tables 3 and 4. The printing inks of Examples 1 to 16 show printability such as excellent plate fogging in an ester / alcohol solvent system as compared with the printing ink compositions of Comparative Examples 1 to 8, and have blocking resistance, adhesiveness, It is possible to provide a printing ink composition that can ensure printing property such as alcohol bleeding resistance and suitability for lamination.

That is, the first invention of the present invention is a polyurethane resin obtained by reacting a urethane prepolymer having an isocyanate group at the terminal obtained by reacting a polyisocyanate containing tolylene diisocyanate and a polymer polyol with an organic diamine and an alkanolamine. ,
A polyurethane resin composition comprising a mixed solvent,
It is related with the polyurethane resin composition characterized by being the following (A)- (F) .
(A) The molar ratio [NCO (total)] / [OH] in the reaction of all isocyanate groups of the polyisocyanate and hydroxyl groups of the polymer polyol is 1.8 to 2.3.
(B) The molar ratio [NCO (TDI)] / [OH] in the reaction between the isocyanate group of tolylene diisocyanate and the hydroxyl group of the polymer polyol is 1.0 to 2.1.
(C) The hydroxyl value of the polyurethane resin is 1.0 to 10.0 mgKOH / g.
(D) The molar ratio d1 / d2 between the number of moles d1 of the organic diamine and the number of moles d2 of the alkanolamine is 3-25.
(E) The mixed solvent includes an ester solvent and an alcohol solvent.
(F) The polymer polyol is composed of a polyester diol and a polyether diol.

Claims (3)

A polyurethane resin obtained by reacting a urethane prepolymer having an isocyanate group at a terminal obtained by reacting a polyisocyanate containing tolylene diisocyanate and a polymer polyol with an organic diamine and an alkanolamine,
A polyurethane resin composition comprising a mixed solvent,
A polyurethane resin composition comprising the following (A) to (E).
(A) The molar ratio [NCO (total)] / [OH] in the reaction of all isocyanate groups of the polyisocyanate and hydroxyl groups of the polymer polyol is 1.8 to 2.3.
(B) The molar ratio [NCO (TDI)] / [OH] in the reaction between the isocyanate group of tolylene diisocyanate and the hydroxyl group of the polymer polyol is 1.0 to 2.1.
(C) The hydroxyl value of the polyurethane resin is 1.0 to 10.0 mgKOH / g.
(D) The molar ratio d1 / d2 between the number of moles d1 of the organic diamine and the number of moles d2 of the alkanolamine is 3-25.
(E) The mixed solvent includes an ester solvent and an alcohol solvent. The polymer polyol consists of polyester diol and polyether diol,
2. The polyurethane resin composition according to claim 1, wherein the polyester polyol is 20 to 80% by weight and the polyether diol is 80 to 20% by weight in the polymer polyol. A printing ink composition comprising the polyurethane resin composition according to claim 1.