WO2021124433A1 - Liquid ink composition, printed matter and laminated body - Google Patents

Abstract

Provided are a liquid ink composition, printed matter and a laminated body, said liquid ink composition containing a polyurethane resin (A) and a vinyl chloride-vinyl acetate copolymer resin (B) having a hydroxyl group. The polyurethane resin (A) comprises: a polyurethane resin (a1) using, as a reaction raw material, a polycarboxylic acid that has two or more carboxyl groups each having at most 6 carbon atoms; and a polyurethane resin (a2) using, as a reaction raw material, a polycarboxylic acid that has two or more carboxyl groups each having at least 7 carbon atoms.

Description

Liquid ink compositions, printed matter and laminated laminates

The present invention relates to a liquid ink composition that can be used as a laminated gravure ink for flexible packaging or a flexographic ink.

Gravure ink and flexo ink are widely used for the purpose of imparting cosmeticity and functionality to the printed material. When the gravure-printed or flexographic-printed object to be printed is used as a food packaging material among packaging materials, it is generally laminated. In this case, various printed materials and laminating processes are used depending on the type of contents and the purpose of use.

In recent years, packaging materials have been diversified, and the adhesion and blocking resistance of printing ink to the printing substrate (when the film on which the ink is printed is stored in a wound state, the ink film becomes a non-printing surface. The conditions for the transition phenomenon) are becoming stricter year by year, including from the viewpoint of improving work efficiency. Among them, among the films used for film packages in recent years, there is a tendency that the number of high-performance films imparted with various barrier properties is increasing. An inorganic or organic barrier coating agent is applied to the surface of these high-performance films, and when gravure printing or flexographic printing is performed using these high-performance films as raw fabrics, the adhesion between the raw fabrics and the ink is generally good. It is often hindered compared to typical films, and often induces troubles in the blocking phenomenon. These high-performance films exist in a wide variety of applications for foods and electronic parts, such as oxygen barriers that block air to prevent deterioration of the contents and water vapor barriers that block water vapor, depending on the type of industry and application. In addition, many of them are technically private, and it is difficult to deal with them compared to general film printing.

Conventionally, in such a laminated product for flexible packaging, by adding a silane coupling agent to a printing ink using a polyurethane resin as a binder, high adhesion to an object to be printed and laminating strength have been improved. It is exemplified (see, for example, Patent Document 1). However, while the types of high-performance films are diversifying, the adhesiveness to the printed material is still not sufficient. It is desired that high adhesiveness can be maintained for a wider range of high-performance films.

Japanese Unexamined Patent Publication No. 2001-2971

An object of the present invention is to provide a liquid ink composition having both adhesion to various functional film substrates and blocking resistance without using a silane coupling agent.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have made a polyurethane resin (A) and a vinyl chloride vinyl acetate copolymer resin (B) using a polyester polyol as a reaction raw material in a liquid ink composition. It was found that it is effective to solve the problem that the polyurethane resin (A) is a liquid ink composition containing the above-mentioned materials and it is effective to use two kinds of polyurethane resins using carboxyl groups having different carbon atoms as reaction raw materials in combination. It was.

That is, the present invention is a liquid ink composition containing a polyurethane resin (A) and a vinyl chloride vinyl acetate copolymer resin (B) having a hydroxyl group, wherein the polyurethane resin (A) has 6 or less carbon atoms. A polyurethane resin (a1) using a polycarboxylic acid having two or more carboxyl groups as a reaction raw material and a polyurethane resin (a2) using a polycarboxylic acid having seven or more carbon atoms and having two or more carboxyl groups as a reaction raw material. ) In combination with the liquid ink composition.

Further, in the present invention, the mass ratio of the polyurethane resin (a1) to the polyurethane resin (a2) ranges from (a1) / (a2) = 5/95 to (a1) / (a2) = 95/5. With respect to a liquid ink composition.

The present invention further relates to a liquid ink composition containing less than 10% by mass of water in the total amount of the composition.

Further, in the present invention, the polyurethane resin (A) further uses a polyether polyol as a reaction raw material, and the mass ratio of the polyether polyol is 1 to 40% by mass of the total amount of the polyurethane resin (A). Regarding.

The present invention further relates to a liquid ink composition in which the polyurethane resin (A) further uses a polyether polyol as a reaction raw material, and the polyether polyol has a number average molecular weight of 100 to 3500.

The liquid ink composition according to any one of the present invention, which further contains a colorant (C) and an organic solvent (D).

The present invention also relates to a liquid ink composition in which the polycarboxylic acid having 6 or less carbon atoms and having two or more carboxyl groups is any one of succinic acid, succinic anhydride, adipic acid, or a mixture thereof. ..

The present invention also relates to a liquid ink composition in which the polycarboxylic acid having 7 or more carbon atoms and having 2 or more carboxyl groups is sebacic acid or dimer acid.

Further, in the present invention, the vinyl chloride acetate copolymer resin (B) has a hydroxyl group, the hydroxyl value thereof is 50 to 200 mg equivalent KOH, and the content of the vinyl chloride component in the copolymer resin. The present invention relates to a liquid ink composition having a content of 80 to 95% by mass.

The present invention also relates to a liquid ink composition in which the organic solvent (D) does not contain an aromatic organic solvent and / or a ketone solvent.

The present invention also relates to a printed matter obtained by printing the liquid ink composition.

In addition, the present invention relates to a laminated laminate made of the printed matter.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a liquid ink composition having both adhesion to various functional film substrates and blocking resistance without using a silane coupling agent.

(Definition of words)
In the present invention, the liquid ink refers to a liquid ink applied to a printing method using a printing plate, such as a gravure ink or a flexo ink, and is preferably a gravure ink or a flexo ink. Further, the liquid ink of the present invention does not contain an active energy curable component, that is, is a liquid ink that is non-reactive with active energy rays.
The "inks" used in the following description all refer to "printing inks". Moreover, all "parts" indicate "mass parts".

The present invention is a liquid ink composition containing a polyurethane resin (A) and a vinyl chloride vinyl acetate copolymer resin (B), wherein the polyurethane resin (A) has two or more carboxyls having 6 or less carbon atoms. A polyurethane resin (a1) using a polycarboxylic acid having a group as a reaction raw material and a polyurethane resin (a2) using a polycarboxylic acid having two or more carboxyl groups having 7 or more carbon atoms as a reaction raw material are used in combination. It is a liquid ink composition characterized by.

The liquid ink composition of the present invention specifically comprises a polyurethane resin (A) and a vinyl chloride vinyl acetate copolymer resin (B) such as ethyl acetate, methyl ethyl ketone, toluene, and isopropyl alcohol (hereinafter sometimes referred to as IPA). Various organic solvents, water (C) if necessary, and various additives are premixed using a dispersion stirrer. Water may be added to the organic solvent in advance to form a water-containing organic solvent, or a specific amount of water may be added separately. In the case of a varnish composition, the varnish composition can be obtained by adding various additives while stirring the solution with a dispersion stirrer and further stirring. In the case of an ink composition, the colorant (D) is added and sufficiently dispersed to obtain an ink composition.

The polyurethane resin (A) used in the liquid ink composition of the present invention is obtained by reacting a polyol, a polyisocyanate, a chain extender, and if necessary, a monovalent active hydrogen compound.

The polyurethane resin (A) used in the liquid ink composition of the present invention has a polyurethane resin (a1) using a polycarboxylic acid having 6 or less carbon atoms and two or more carboxyl groups as a reaction raw material, and a polyurethane resin (a1) having two or more carbon atoms. It is essential to blend two types of polyurethane resin (a2), which is a polyurethane resin (a2) using a polycarboxylic acid having 7 or more and 2 or more carboxyl groups as a reaction raw material, and each polyurethane resin is a compound having 2 or more hydroxyl groups. Obtained by reacting with.
The polyester polyol can further increase the lamination strength by introducing an ester group to increase the polarity, but the raw material is a polycarboxylic acid having 7 or more carbon atoms and 2 or more carboxyl groups. By doing so, it is possible to obtain both appropriate flexibility and laminate strength, and by using a polycarboxylic acid having 6 or less carbon atoms and two or more carboxyl groups as a raw material, excessive softening of the resin is prevented. It is possible to improve the blocking resistance after printing.

Examples of polycarboxylic acids having 6 or less carbon atoms and two or more carboxyl groups include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid, and anhydrides of these acids. You can use things.
Examples of polycarboxylic acids having 7 or more carbon atoms and 2 or more carboxyl groups include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and anhydrides of these acids, and pimeric acid. , Suberic acid, azelaic acid, sebacic acid, dimer acid and other aliphatic dicarboxylic acids, trimellitic acid and its anhydrides and other tricarboxylic acids, benzenetetracarboxylic acid, benzenepentacarboxylic acid, benzenehexacarboxylic acid and these acids. Anhydrous or the like can be used.
Among them, succinic acid, anhydrous succinic acid, and adipic acid are used alone or in combination as polycarboxylic acids having 6 or less carbon atoms, and sebacic acid and dimer acid are used alone as polycarboxylic acids having 7 or more carbon atoms. When they are used in combination, they are preferable in that they can achieve both adhesion to a wide variety of films, blocking resistance, and high lamination strength.

Examples of the compound having two or more hydroxyl groups include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, and tri. Glycols such as ethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol; 2-methyl-1,5-pentanediol, 3-methyl-1, 5-pentanediol, 1,2-butanediol, 1,3-butanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,2-propanediol, 2-methyl-1,3-propane Didiol, neopentanediol, 2-isopropyl-1,4-butanediol, 2,4-dimethyl-1,5-pentanediol 2,4-diethyl-1,5-pentanediol, 2-ethyl-1,3- Glyxane having a branched structure such as hexanediol, 2-ethyl-1,6-hexanediol, 3,5-heptandiol, 2-methyl-1,8-octanediol; glycerin, trimethylolpropane, trimethylolethane, penta Ellisritol, sorbitol and the like can be used. These compounds may be used alone or in combination of two or more.

The number average molecular weight of the polyester polyol is preferably in the range of 500 to 8,000, more preferably in the range of 700 to 7,000, and even more preferably in the range of 800 to 6,000. ..
In the present invention, the number average molecular weight and the weight average molecular weight show the values measured under the following conditions by the gel permeation chromatography (GPC) method.

Measuring device: High-speed GPC device ("HLC-8220GPC" manufactured by Tosoh Corporation)
Column: The following columns manufactured by Tosoh Corporation were connected in series and used.
"TSKgel G5000" (7.8 mm ID x 30 cm) x 1 "TSKgel G4000" (7.8 mm ID x 30 cm) x 1 "TSKgel G3000" (7.8 mm ID x 30 cm) x 1 This "TSKgel G2000" (7.8 mm ID x 30 cm) x 1 Detector: RI (Differential Refractometer)
Column temperature: 40 ° C
Eluent: tetrahydrofuran (THF)
Flow velocity: 1.0 mL / min Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4% by mass)
Standard sample: A calibration curve was prepared using the following standard polystyrene.

[Standard polystyrene]
"TSKgel Standard Polystyrene A-500" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene A-1000" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene A-2500" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene A-5000" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-1" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-2" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-4" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-10" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-20" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-40" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-80" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-128" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-288" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-550" manufactured by Tosoh Corporation

A polyurethane resin (a1) using a polycarboxylic acid having 6 or less carbon atoms and having two or more carboxyl groups as a reaction raw material used in the liquid ink composition of the present invention and two or more carbon atoms having 7 or more carbon atoms. The mass ratio of the polyurethane resin (a2) using a polycarboxylic acid having a carboxyl group as a reaction raw material is in the range of (a1) / (a2) = 5/95 to (a1) / (a2) = 95/5. Is preferable.
If the mass ratio of the polyurethane resin (a1) to the polyurethane resin (a2) is in the range of (a1) / (a2) = 5/95 to (a1) / (a2) = 95/5, after printing. While suppressing blocking resistance, it is possible to maintain adhesion to a wide variety of functional film substrates.
Among them, the molar ratio is preferably in the range of 10/90 to 90/10, and most preferably in the range of 20/80 to 80/20.

Further, it is more preferable that the polyether polyol is contained in the range of 1 to 40% by mass with respect to the polyurethane resin as a constituent component of each of the polyurethane resins (a1) and (a2). As the polyether polyol, various known ether polyols generally used in the production of polyurethane resin can be used, and one kind or two or more kinds may be used in combination. Examples thereof include polyether polyols of polymers such as ethylene oxide, propylene oxide and tetrahydrofuran, or copolymers. When the content of the polyether polyol is 1% by mass or more based on 100% by mass of the polyurethane resin, the solubility of the urethane resin in a ketone, ester, or alcohol solvent is good, and the ink film is reconstituted in the solvent. Solubility does not easily decrease, and the tone reproducibility of printed matter does not deteriorate easily. Further, if it is 40% by mass or less, the blocking resistance is unlikely to decrease.
Above all, it is more preferable to contain the polyether polyol in the range of 1 to 30% by mass, and most preferably in the range of 1 to 20% by mass with respect to the polyurethane resin.

Further, the number average molecular weight of the polyether polyol is more preferably 100 to 3500. When the number average molecular weight of the polyether polyol is 100 or more, the film of the polyurethane resin does not become hard and the adhesiveness to the polyester film is less likely to decrease. When the number average molecular weight is 3500 or less, the tendency of the polyurethane resin film to become brittle can be suppressed, and the blocking resistance of the ink film tends to be difficult to decrease.
Among them, it is more preferable that the number average molecular weight of the polyether polyol is 100 to 3000, and most preferably 100 to 2000.

The polyether polyol may be contained as a component of either one of the polyurethane resin (a1) and the polyurethane resin (a2), or may be contained in both components.
Specifically, as the polyether polyol, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6 -Hexanediol, neopentyl glycol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexanediol , Bifunctional alcohols (glycols) such as 1,4-cyclohexanedimethanol; trifunctional or tetrafunctional aliphatic alcohols such as glycerin, trimethylolpropane, pentaerythritol; bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated Bisphenol such as bisphenol F;

Polytetramethylene obtained by addition-polymerizing an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, or cyclohexylene in the presence of a polymerization initiator such as the glycol trifunctional or tetrafunctional aliphatic alcohol. Examples thereof include polyether polyols such as glycols, polypropylene glycols, polyethylene glycols, and polytrimethylene glycols; and polyether urethane polyols obtained by further increasing the amount of the polyether polyol with the aromatic or aliphatic polyisocyanate.

As the diisocyanate compound used in the polyurethane resin (A) such as the polyurethane resin (a1) and the polyurethane resin (a2) in the liquid ink composition of the present invention, various known aromatics generally used in the production of the polyurethane resin. Examples thereof include diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates. For example, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylenedi isocyanate, 1-methyl-2,5-phenylene diisocyanate, 1 -Methyl-2,6-phenylene diisocyanate, 1-methyl-3,5-phenylene diisocyanate, 1-ethyl-2,4-phenylene diisocyanate, 1-isopropyl-2,4-phenylene diisocyanate, 1,3-dimethyl-2 , 4-Fene diisocyanate, 1,3-dimethyl-4,6-phenylene diisocyanate, 1,4-dimethyl-2,5-phenylene diisocyanate, diethylbenzene diisocyanate, diisopropylbenzene diisocyanate, 1-methyl-3,5-diethylbenzene diisocyanate, 3-Methyl-1,5-diethylbenzene-2,4-diisocyanate, 1,3,5-triethylbenzene-2,4-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methyl -Naphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1-dinaphthyl-2,2'-diisocyanate, biphenyl-2,4'-diisocyanate, biphenyl-4 , 4'-diisocyanate, 3-3'-dimethylbiphenyl-4,4'-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, diphenylmethane-2,4-diisocyanate and other aromatic polyisocyanides Teluene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene diisocyanate, 1,3-di (isocyanis) Methyl) cyclohexane, 1,4-di (isocyanisocyanate methyl) cyclohexane, lysine diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexamethylene diisocyanate, 2,4'-dicyclohexamethylene diisocyanate, 2,2'-dicyclohexamethylene diisocyanate, 3, 3'-dimethyl-4,4'-dicyclohexylmethane Aliphatic compounds such as diisocyanates or alicyclic polyisocyanates can be used. These polyisocyanates may be used alone or in combination of two or more. Among these, an aliphatic polyisocyanate and / or an alicyclic polyisocyanate is preferably used from the viewpoint of obtaining appropriate flexibility, and isophorone diisocyanate or hexamethylene diisocyanate is used from the viewpoint of further improving the adhesive strength. Is more preferable.

Examples of the chain extender used in the polyurethane resin (A) in the liquid ink composition of the present invention include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, and dicyclohexylmethane-4,4'-diamine. In addition, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2- Amines having a hydroxyl group in the molecule such as hydroxypyrropyrethylenediamine, di-2-hydroxypyrropylethylenediamine, and di-2-hydroxypropylethylenediamine can also be used. These chain extenders can be used alone or in admixture of two or more.
In addition, a monovalent active hydrogen compound can also be used as a terminal sequestering agent for the purpose of stopping the reaction. Examples of such a compound include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. Further, especially when it is desired to introduce a carboxyl group into a polyurethane resin, amino acids such as glycine and L-alanine can be used as a reaction terminator. These end-blocking agents can be used alone or in admixture of two or more.

The polyurethane resin (A) used in the liquid ink composition of the present invention is obtained by reacting a polyol, a polyisocyanate, a chain extender, and if necessary, a monovalent active hydrogen compound. For example, a polyester polyol, a combined polyol, and a diisocyanate compound are reacted at a ratio of an excess of isocyanate groups to obtain a prepolymer having a terminal isocyanate group, and the obtained prepolymer is placed in a suitable solvent, that is, a solvent for liquid ink. Ester solvents such as ethyl acetate, propyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; alcohol solvents such as methanol, ethanol, isopropyl alcohol and n-butanol; toluene, A hydrocarbon solvent such as xylene, methylcyclohexane, ethylcyclohexane; or a two-step method of reacting with a chain extender and / or terminal blocker in a mixed solvent thereof, or a polyester polyol and a combined polyol, a diisocyanate compound, It is produced by a one-step method in which a chain extender and / or a terminal blocker are reacted at once in a suitable solvent among the above. Among these methods, in order to obtain a uniform polyurethane resin (A), the two-step method is preferable. When the polyurethane resin (A) is produced by the two-step method, the total (equivalent ratio) of the amino groups of the chain extender and / or the terminal blocker is 1 / 0.9 to 1.3. It is preferable to react with. When the equivalent ratio of the isocyanate group to the amino group is less than 1 / 1.3, the chain extender and / or the terminal sequestering agent remain unreacted, the polyurethane resin turns yellow, and the odor after printing is generated. It may occur.

The weight average molecular weight of the polyurethane resin (A) is preferably in the range of 10,000 to 100,000, more preferably in the range of 15,000 to 95,000. If the weight average molecular weight of the polyurethane resin (A) is 10,000 or more, the blocking resistance, the strength of the printing film, the oil resistance, etc. of the obtained ink composition are unlikely to decrease, and if it is 100,000 or less, the obtained ink composition is obtained. The viscosity of the ink composition to be obtained does not become too high, and the gloss of the printing film can be easily maintained. The weight average molecular weight of the polyurethane resin (A) indicates a value obtained by measuring in the same manner as the number average molecular weight of the polyester polyol.
The content of the polyurethane resin (A) used in the liquid ink composition of the present invention with respect to the total amount of the composition, that is, the content of the total amount of the polyurethane resin (a1) and the polyurethane resin (a2) with respect to the total amount of the composition is the content of the ink. From the viewpoint of ensuring sufficient adhesiveness to the object to be printed, it is preferably 4% by mass or more with respect to the total amount of the composition, and from the viewpoint of appropriate ink viscosity and work efficiency during ink production / printing, 25% by mass or less is preferable, and further. The range of 6 to 15% by mass is preferable.

Further, in the liquid ink composition of the present invention, in addition to the polyurethane resin (A), a vinyl chloride vinyl acetate copolymer resin (B) having a hydroxyl group is essential. By using the polyurethane resin (A) and the vinyl chloride vinyl acetate copolymer resin (B) in combination, the blocking resistance can be further improved.

The vinyl chloride vinyl acetate copolymer resin (B) having a hydroxyl group has a hydroxyl value of 50 to 200 mgKOH / g, and the content ratio of the vinyl chloride component in the copolymer resin is 80 to 95% by weight. Is preferable.

The vinyl chloride vinyl acetate copolymer resin having a hydroxyl group used in the present invention can be obtained by two kinds of methods. One is obtained by copolymerizing a vinyl chloride monomer, a vinyl acetate monomer and a vinyl alcohol in an appropriate ratio. The other is obtained by copolymerizing vinyl chloride and vinyl acetate and then partially saponifying the vinyl acetate. In the vinyl chloride vinyl acetate copolymer resin having a hydroxyl group, the properties of the resin film and the resin dissolution behavior are determined by the monomer ratio of vinyl chloride, vinyl acetate and vinyl alcohol. That is, vinyl chloride imparts toughness and hardness of the resin film, vinyl acetate imparts adhesiveness and flexibility, and vinyl alcohol imparts good solubility in polar solvents.

When the liquid ink composition of the present invention is used as a laminating ink for flexible packaging, it has a hydroxyl group because it is necessary to satisfy all of these performances such as adhesiveness, blocking resistance, laminating strength, boil retort suitability, and printability. The vinyl chloride vinyl acetate copolymer resin has an appropriate monomer ratio. That is, 80 to 95 parts by mass of vinyl chloride is preferable with respect to 100 parts by mass of the vinyl chloride vinyl acetate copolymer resin having a hydroxyl group. If it is 80 parts by mass or more, the toughness of the resin film can be maintained and blocking resistance can be ensured. If it is 95 parts by mass or less, the resin film does not become too hard and the adhesiveness is unlikely to decrease. The hydroxyl value obtained from vinyl alcohol is preferably 50 to 200 mgKOH / g. If it is 50 mgKOH / g or more, the solubility in a polar solvent is good, and the printability is easily stable. If it is 200 mgKOH / g or less, the water resistance does not decrease and the boil and retort suitability can be kept good.

Water (C) may be added to the liquid ink composition of the present invention together with the organic solvent as a volatile component. By adding water (C), the drying property of the ink can be controlled, and particularly in gravure printing, the gradation portion having a small amount of ink transfer, which is a feature thereof, can be beautifully reproduced. The amount of water (C) added is preferably in the range of 0.3 to 10% by mass of the total amount of the ink composition from the viewpoint of improving printability. When the amount of water added is 0.3% by mass or more, the reproducibility of the gradation portion tends to be good without deteriorating the effect of suppressing the drying of the ink, and the amount of water added is 10 of the total amount of the ink composition. If it is mass% or less, it is possible to suppress a decrease in ink stability.
Further, by adding such water (C), it is possible to reduce the organic solvent component used, which leads to environmental friendliness. Water (C) may be added in advance to the organic solvent (D) to form a water-containing organic solvent, or a specific amount may be added separately.

(Colorant)
The liquid ink composition of the present invention can be used as a density adjusting varnish and an overprint varnish for inks that do not contain a colorant, and is used for design printing and the like for the purpose of imparting cosmetic properties including a colorant. It can also be used as an ink containing a colorant.
Pigments are preferable as the colorant, and inorganic pigments and organic pigments used in general inks, paints, recording agents and the like can be mentioned. Organic pigments include soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, anthraquinone, dianthraquinone, anthrapyrimidine, perylene, perinone, and quinacridone. Pigments such as thioindigo-based, dioxazine-based, isoindolinone-based, quinophthalone-based, azomethine-azo-based, flavanthlon-based, diketopyrrolopyrrole-based, isoindoline-based, indanslon-based, and carbon black-based pigments can be mentioned. Also, for example, Carmin 6B, Lake Red C, Permanent Red 2B, Disazo Yellow, Pyrazolone Orange, Carmin FB, Chromophthal Yellow, Chromophthal Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Magenta, Quinacridone Red, Indance Examples thereof include lonblue, pyrimidine yellow, thioindigo bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, and daylight fluorescent pigment. Further, both unacidified treated pigments and acidic treated pigments can be used. Specific examples of preferable organic pigments are given below.

Examples of black pigments include C.I. I. Pigment Black 1, C.I. I. Pigment Black 6, C.I. I. Pigment Black 7, C.I. I. Pigment Black 9, C.I. I. Pigment Black 20 and the like.

Examples of the indigo pigment include C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 1, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 15: 4, C.I. I. Pigment Blue 15: 5, C.I. I. Pigment Blue 15: 6, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 17: 1, C.I. I. Pigment Blue 22, C.I. I. Pigment Blue 24: 1, C.I. I. Pigment Blue 25, C.I. I. Pigment Blue 26, C.I. I. Pigment Blue 60, C.I. I. Pigment Blue 61, C.I. I. Pigment Blue 62, C.I. I. Pigment Blue 63, C.I. I. Pigment Blue 64, C.I. I. Pigment Blue 75, C.I. I. Pigment Blue 79, C.I. I. Pigment Blue 80 and the like.

Examples of green pigments include C.I. I. Pigment Green 1, C.I. I. Pigment Green 4, C.I. I. Pigment Green 7, C.I. I. Pigment Green 8, C.I. I. Pigment Green 10, C.I. I. Pigment Green 36 and the like.

Examples of the red pigment include C.I. I. Pigment Red 1, C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 4, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 8, C.I. I. Pigment Red 9, C.I. I. Pigment Red 10, C.I. I. Pigment Red 11, C.I. I. Pigment Red 12, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 17, C.I. I. Pigment Red 18, C.I. I. Pigment Red 19, C.I. I. Pigment Red 20, C.I. I. Pigment Red 21, C.I. I. Pigment Red 22, C.I. I. Pigment Red 23, C.I. I. Pigment Red 31, C.I. I. Pigment Red 32, C.I. I. Pigment Red 38, C.I. I. Pigment Red 41, C.I. I. Pigment Red 43, C.I. I. Pigment Red 46, C.I. I. Pigment Red 48, C.I. I. Pigment Red 48: 1, C.I. I. Pigment Red 48: 2, C.I. I. Pigment Red 48: 3, C.I. I. Pigment Red 48: 4, C.I. I. Pigment Red 48: 5, C.I. I. Pigment Red 48: 6, C.I. I. Pigment Red 49, C.I. I. Pigment Red 49: 1, C.I. I. Pigment Red 49: 2, C.I. I. Pigment Red 49: 3, C.I. I. Pigment Red 52, C.I. I. Pigment Red 52: 1, C.I. I. Pigment Red 52: 2, C.I. I. Pigment Red 53, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 53: 2, C.I. I. Pigment Red 53: 3, C.I. I. Pigment Red 54, C.I. I. Pigment Red 57, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 58, C.I. I. Pigment Red 58: 1, C.I. I. Pigment Red 58: 2, C.I. I. Pigment Red 58: 3, C.I. I. Pigment Red 58: 4, C.I. I. Pigment Red 60: 1, C.I. I. Pigment Red 63, C.I. I. Pigment Red 63: 1, C.I. I. Pigment Red 63: 2, C.I. I. Pigment Red 63: 3, C.I. I. Pigment Red 64: 1, C.I. I. Pigment Red 68, C.I. I. Pigment Red 68, C.I. I. Pigment Red 81: 1, C.I. I. Pigment Red 83, C.I. I. Pigment Red 88, C.I. I. Pigment Red 89, C.I. I. Pigment Red 95, C.I. I. Pigment Red 112, C.I. I. Pigment Red 114, C.I. I. Pigment Red 119, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 136, C.I. I. Pigment Red 144, C.I. I. Pigment Red 146, C.I. I. Pigment Red 147, C.I. I. Pigment Red 149, C.I. I. Pigment Red 150, C.I. I. Pigment Red 164, C.I. I. Pigment Red 166, C.I. I. Pigment Red 168, C.I. I. Pigment Red 169, C.I. I. Pigment Red 170, C.I. I. Pigment Red 171 and C.I. I. Pigment Red 172, C.I. I. Pigment Red 175, C.I. I. Pigment Red 176, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 179, C.I. I. Pigment Red 180, C.I. I. Pigment Red 181 and C.I. I. Pigment Red 182, C.I. I. Pigment Red 183, C.I. I. Pigment Red 184, C.I. I. Pigment Red 185, C.I. I. Pigment Red 187, C.I. I. Pigment Red 188, C.I. I. Pigment Red 190, C.I. I. Pigment Red 192, C.I. I. Pigment Red 193, C.I. I. Pigment Red 194, C.I. I. Pigment Red 200, C.I. I. Pigment Red 202, C.I. I. Pigment Red 206, C.I. I. Pigment Red 207, C.I. I. Pigment Red 208, C.I. I. Pigment Red 209, C.I. I. Pigment Red 210, C.I. I. Pigment Red 211, C.I. I. Pigment Red 213, C.I. I. Pigment Red 214, C.I. I. Pigment Red 216, C.I. I. Pigment Red 215, C.I. I. Pigment Red 216, C.I. I. Pigment Red 220, C.I. I. Pigment Red 221 and C.I. I. Pigment Red 223, C.I. I. Pigment Red 224, C.I. I. Pigment Red 226, C.I. I. Pigment Red 237, C.I. I. Pigment Red 238, C.I. I. Pigment Red 239, C.I. I. Pigment Red 240, C.I. I. Pigment Red 242, C.I. I. Pigment Red 245, C.I. I. Pigment Red 247, C.I. I. Pigment Red 248, C.I. I. Pigment Red 251 and C.I. I. Pigment Red 253, C.I. I. Pigment Red 254, C.I. I. Pigment Red 255, C.I. I. Pigment Red 256, C.I. I. Pigment Red 257, C.I. I. Pigment Red 258, C.I. I. Pigment Red 260, C.I. I. Pigment Red 262, C.I. I. Pigment Red 263, C.I. I. Pigment Red 264, C.I. I. Pigment Red 266, C.I. I. Pigment Red 268, C.I. I. Pigment Red 269, C.I. I. Pigment Red 270, C.I. I. Pigment Red 271, C.I. I. Pigment Red 272, C.I. I. Pigment Red 279, etc.

Examples of purple pigments include C.I. I. Pigment Violet 1, C.I. I. Pigment Violet 2, C.I. I. Pigment Violet 3, C.I. I. Pigment Violet 3: 1, C.I. I. Pigment Violet 3: 3, C.I. I. Pigment Violet 5: 1, C.I. I. Pigment Violet 13, C.I. I. Pigment Violet 19 (γ type, β type), C.I. I. Pigment Violet 23, C.I. I. Pigment Violet 25, C.I. I. Pigment Violet 27, C.I. I. Pigment Violet 29, C.I. I. Pigment Violet 31, C.I. I. Pigment Violet 32, C.I. I. Pigment Violet 36, C.I. I. Pigment Violet 37, C.I. I. Pigment Violet 38, C.I. I. Pigment Violet 42, C.I. I. Pigment Violet 50 and the like.

Examples of the yellow pigment include C.I. I. Pigment Yellow 1, C.I. I. Pigment Yellow 3, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, Pigment Yellow 17, C.I. I. Pigment Yellow 24, C.I. I. Pigment Yellow 42, C.I. I. Pigment Yellow 55, C.I. I. Pigment Yellow 62, C.I. I. Pigment Yellow 65, C.I. I. Pigment Yellow 74, C.I. I. Pigment Yellow 83, C.I. I. Pigment Yellow 86, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I. Pigment Yellow 95, C.I. I. Pigment Yellow 109, C.I. I. Pigment Yellow 110, C.I. I. Pigment Yellow 117, C.I. I. Pigment Yellow 120, Pigment Yellow 125, C.I. I. Pigment Yellow 128, C.I. I. Pigment Yellow 129, C.I. I. Pigment Yellow 137, C.I. I. Pigment, Yellow 138, C.I. I. Pigment Yellow 139, C.I. I. Pigment Yellow 147, C.I. I. Pigment Yellow 148, C.I. I. Pigment Yellow 150, C.I. I. Pigment Yellow 151, C.I. I. Pigment Yellow 153, C.I. I. Pigment Yellow 154, C.I. I. Pigment Yellow 155, C.I. I. Pigment Yellow 166, C.I. I. Pigment Yellow 168, C.I. I. Pigment Yellow 174, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 185 and C.I. I. Pigment Yellow 213 and the like.

Examples of the orange pigment include C.I. I. Pigment Orange 5, C.I. I. Pigment Orange 13, C.I. I. Pigment Orange 16, C.I. I. Pigment Orange 34, C.I. I. Pigment Orange 36, C.I. I. Pigment Orange 37, C.I. I. Pigment O Orange 38, C.I. I. Pigment Orange 43, C.I. I. Pigment Orange 51, C.I. I. Pigment range 55, C.I. I. Pigment Orange 59, C.I. I. Pigment Orange 61, C.I. I. Pigment Orange 64, C.I. I. Pigment Orange 71, or C.I. I. Pigment Orange 74 and the like.

Examples of brown pigments include C.I. I. Pigment Brown 23, C.I. I. Pigment Brown 25, or C.I. I. Pigment Brown 26 and the like.

Among them, as a preferable pigment, as a black pigment, C.I. I. Pigment Black 7,
As an indigo pigment, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 1, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 15: 4, C.I. I. Pigment Blue 15: 6,
As a green pigment, C.I. I. Pigment Green 7,
As a red pigment, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 48: 1, C.I. I. Pigment Red 48: 2, C.I. I. Pigment Red 48: 3, C.I. I. Pigment Red 146, C.I. I. Pigment Red 242, C.I. I. Pigment Red 185, C.I. I. Pigment Red 122, C.I. I. Pigment Red 178, C.I. I. Pigment Red 149, C.I. I. Pigment Red 144, C.I. I. Pigment Red 166,
As a purple pigment, C.I. I. Pigment Violet 23, C.I. I. Pigment Violet 37,
As a yellow pigment, C.I. I. Pigment Yellow 83, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 139,
As an orange pigment, C.I. I. Pigment Orange 38, C.I. I. Pigment Orange 13, C.I. I. Pigment Orange 34, C.I. I. Pigment Orange 64,
Etc., and it is preferable to use at least one or two or more selected from these groups.

Examples of inorganic pigments include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, lithobon, antimony white, and gypsum. Among the inorganic pigments, the use of titanium oxide is particularly preferable. Titanium oxide has a white color and is preferable from the viewpoints of coloring power, hiding power, chemical resistance and weather resistance, and from the viewpoint of printing performance, the titanium oxide is preferably treated with silica and / or alumina.

Examples of non-white inorganic pigments include aluminum particles, mica (mica), bronze powder, chrome vermilion, chrome yellow, cadmium yellow, cadmium red, ultramarine, dark blue, red iron oxide, yellow iron oxide, iron black, and zircon. Although aluminum is in the form of powder or paste, it is preferably used in the form of paste from the viewpoint of handleability and safety, and whether chrome yellow or non-leafing is used is appropriately selected from the viewpoint of brightness and density.

The pigment is in an amount sufficient to secure the concentration and coloring power of the liquid ink composition, that is, 1 to 60% by mass with respect to the total mass of the ink, and 10 to 90% by mass in terms of the solid content weight ratio in the ink. It is preferable that it is contained in. In addition, these pigments can be used alone or in combination of two or more.

(Organic solvent)
The organic solvent used in the liquid ink composition of the present invention is not particularly limited, and is, for example, an aromatic hydrocarbon-based organic solvent such as toluene, xylene, Solbesso # 100, Solbesso # 150, hexane, methylcyclohexane, heptane, and the like. Examples thereof include aliphatic hydrocarbon-based organic solvents such as octane and decane, and various ester-based organic solvents such as methyl acetate, ethyl acetate, isopropyl acetate, normal propyl acetate, butyl acetate, amyl acetate, ethyl formate, and butyl propionate. Also, as water-mixable organic solvents, alcohol-based solvents such as methanol, ethanol, propanol, butanol, and isopropyl alcohol, ketone-based solvents such as acetone, methyl ethyl ketone, and cyclohaxanone, ethylene glycol (mono, di) methyl ether, and ethylene glycol (mono, di) ethyl. Ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono, di) methyl ether, diethylene glycol (mono, di) ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono, di) Examples thereof include various glycol ether-based organic solvents such as di) methyl ether, propylene glycol (mono, di) methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol (mono, di) methyl ether. These can be used alone or in combination of two or more.

In terms of both work hygiene during printing and harmfulness of packaging materials, use ethyl acetate, propyl acetate, isopropanol, normal propanol, etc., and do not use aromatic solvents such as toluene or ketone solvents such as methyl ethyl ketone. Is more preferable.
Of these, a mixture of isopropyl alcohol / ethyl acetate / methoxypropanol is more preferable from the viewpoint of solubility in polyurethane resin and nitrocellulose. Further, glycol ethers can be added as long as it is less than 10% by mass of the total amount of ink for drying adjustment.

Examples of the resin to be used in combination with the liquid ink composition of the present invention as needed include resins other than the polyurethane resin and vinyl chloride-vinyl acetate copolymer resin, for example, chlorinated polypropylene resin and ethylene-vinyl acetate copolymer weight. Fiber element-based resins such as coalesced resin, vinyl acetate resin, polyamide resin, nitrified cotton, cellulose acetate propionate (CAP) and cellulose acetate butironate (CAB), acrylic resin, polyester resin, alkyd resin, Examples thereof include polyvinyl chloride resin, rosin-based resin, rosin-modified maleic acid resin, ketone resin, cyclized rubber, rubber chloride, butyral, and petroleum resin. The combined resin can be used alone or in combination of two or more. The content of the combined resin is preferably 1 to 25% by weight, more preferably 2 to 15% by weight, based on the total weight of the ink.

The liquid ink composition of the present invention further contains a wax, a chelate-based cross-linking agent, an extender pigment, a leveling agent, a defoaming agent, a plasticizer, an infrared absorber, an ultraviolet absorber, a fragrance, a flame retardant and the like, if necessary. You can also do it.

The liquid ink composition of the present invention can be produced by dissolving and / or dispersing a binder resin, a pigment, or the like in an organic solvent. Specifically, it is possible to produce a pigment dispersion in which a pigment is dispersed in an organic solvent with a binder resin, and to produce an ink by blending the obtained pigment dispersion with another compound or the like as necessary. it can.

In order to stably disperse the pigment in the organic solvent, the resin alone can be dispersed, but in order to further stably disperse the pigment, a pigment dispersant can also be used in combination. As the pigment dispersant, surfactants such as anionic, nonionic, cationic and amphoteric can be used. For example, a comb-shaped structure polymer compound obtained by adding polyester to polyethyleneimine, an alkylamine derivative of an α-olefin maleic acid polymer, and the like can be mentioned. Specific examples thereof include the Sol Spurs series (ZENECA), the Azisper series (Ajinomoto), and the Homogenol series (Kao). Moreover, BYK series (Big Chemie), EFKA series (EFKA) and the like can also be used as appropriate. The dispersant is preferably contained in the ink in an amount of 0.05% by weight or more and 5% by weight or less from the viewpoint of laminating suitability with respect to the total weight of the ink from the viewpoint of storage stability of the ink, and more preferably 0. It is in the range of 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 pulverized media of the disperser, the filling rate of the pulverized media, the dispersion treatment time, the discharge rate of the pigment dispersion, the viscosity of the pigment dispersion, and the like. can do. 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.
If the ink contains air bubbles or unexpectedly coarse particles, it is preferable to remove them by filtration or the like in order to deteriorate the quality of the printed matter. As the filter, a conventionally known one can be used.

The viscosity of the ink produced by the above method should be in the range of 10 mPa · s or more from the viewpoint of preventing the pigment from settling and appropriately dispersing the pigment, and 1000 mPa · s or less from the viewpoint of workability efficiency during ink production or printing. preferable. The viscosity is the viscosity measured at 25 ° C. with a B-type viscometer manufactured by Tokimec.
The viscosity of the ink can be adjusted by appropriately selecting the type and amount of raw materials used, such as polyurethane resin, colorant, and organic solvent. Further, the viscosity of the ink can be adjusted by adjusting the particle size and the particle size distribution of the pigment in the ink.

When the colorant (D) is used in the liquid ink composition of the present invention, the hue may be yellow, red, indigo, ink, or white depending on the type of the colorant (D) used. There are 5 colors, and there are 3 colors of red (orange), grass (green), and purple as the outer color of the process gamut. Furthermore, transparent yellow, peony, vermilion, brown, gold, silver, pearl, and almost transparent medium for adjusting the color density (including extender pigment if necessary) are prepared as base colors. The ink for boil retort is appropriately selected in consideration of pigment migration and heat resistance. The base ink of each hue is diluted with a diluting solvent to a viscosity and concentration suitable for gravure printing or flexographic printing, and is supplied to each printing unit alone or mixed.

As a printing method, it is possible to print by a printing method using a known plate such as gravure printing or flexographic printing, but it is particularly preferable to print by the gravure printing method. As the cylinder used for gravure printing, known cylinders such as engraving type and corrosion type are used.

The liquid ink composition of the present invention has excellent adhesion to various substrates and can be used for printing on paper, synthetic paper, thermoplastic resin film, plastic products, steel plates, etc., and is an electronically engraved concave plate. For gravure printing using a gravure printing plate with, etc., or for flexographic printing using a flexographic printing plate with a resin plate, etc., while for an inkjet method that ejects ink from an inkjet nozzle without using a plate. Ink is excluded.
That is, in the case of inkjet ink, the ink droplets ejected from the nozzle directly adhere to the substrate to form a printed matter, whereas in the liquid printing ink of the present invention, the printing ink is once adhered to and transferred to the printing plate or printing pattern. After that, only the ink is brought into close contact with the base material again, and if necessary, it is dried to obtain a printed matter.
The film thickness of the printing ink formed by the gravure printing method or the flexographic printing method using the liquid printing ink of the present invention is, for example, 10 μm or less, preferably 5 μm or less.

The base material used in the present invention is not particularly limited, and a paper or plastic base material usually used in the gravure printing field or a flexible packaging base material used in the food packaging field may be used. For example, in the case of paper, high-quality paper, kraft paper, pure white roll paper, glassin paper, parchment paper, Manila balls, white balls, coats used for printing packaging materials and packages for cosmetics, beverages, pharmaceuticals, toys, equipment, etc. Examples thereof include paper, art paper, imitation paper, thin paper, thick paper, paper such as polyethylene-coated paper, and various synthetic papers.

The film base material is a polyamide resin such as nylon 6, nylon 66, nylon 46, polyethylene terephthalate (hereinafter sometimes referred to as PET), polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, poly. Polyester resins such as butylene naphthalate, polyhydroxycarboxylic acids such as polylactic acid, biodegradable resins such as aliphatic polyester resins such as poly (ethylene succinate) and poly (butylene succinate), polypropylene, polyethylene and the like. Examples thereof include films made of thermoplastic resins such as polyolefin resins, polyimide resins, polyarylate resins or mixtures thereof, and laminates thereof. Among them, films made of polyethylene terephthalate (PET), polyester, polyamide, polyethylene and polypropylene are used. Can be preferably used. These base films may be unstretched films or stretched films, and the production method thereof is not limited. Further, the thickness of the base film is not particularly limited, but usually it may be in the range of 1 to 500 μm.
The printed surface of the base film is preferably subjected to a corona discharge treatment, and aluminum, silica, alumina, or the like may be vapor-deposited.

The present invention will be described in more detail with reference to Examples. Hereinafter, "parts" and "%" are both based on mass.
The weight average molecular weight (in terms of polystyrene) measured by GPC (gel permeation chromatography) in the present invention was measured using an HLC8220 system manufactured by Toso Co., Ltd. under the following conditions.
Separation column: Uses 4 _{TSKgelGMH HR-N manufactured by Tosoh Corporation.} Column temperature: 40 ° C. Moving layer: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd. Flow velocity: 1.0 ml / min. Sample concentration: 1.0% by weight. Sample injection volume: 100 microliters. Detector: Differential refractometer.
The viscosity was measured at 25 ° C. with a Tokimec B-type viscometer.

[Synthesis of polyurethane resin (a1)]
(Synthesis Example 1) a1-1
80 parts of polyester polyol (hydroxyl value: 57 mgKOH / g) made from neopentyl glycol and succinic acid, neopentyl glycol and succinate in a four-necked flask equipped with a stirrer, thermometer, recirculation cooler and nitrogen gas introduction tube. 20 parts of polyester polyol (hydroxyl value: 110 mgKOH / g) made from acid and 22.5 parts of isophorone diisocyanate are charged and reacted at 90 ° C. for 10 hours under a nitrogen stream to urethane having an isocyanate group content of 2.84% by mass. After producing the prepolymer, 66 parts of ethyl acetate was added thereto to prepare a uniform solution of urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 7.25 parts of isophorone diamine, 0.27 parts of di-n-butylamine, 131 parts of ethyl acetate and 106 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours. To obtain a polyurethane resin solution a1-1. The obtained polyurethane resin solution a1-1 had a resin solid content concentration of 30.1% by mass and a weight average molecular weight of the resin solid content of 30,000.

(Synthesis Example 2) a1-2
80 parts of polyester polyol (hydroxyl value: 57 mgKOH / g) made from neopentyl glycol and adipic acid, neopentyl glycol and adipine in a four-necked flask equipped with a stirrer, thermometer, recirculation cooler and nitrogen gas introduction tube. 20 parts of polyester polyol (hydroxyl value: 110 mgKOH / g) made from acid and 22.5 parts of isophorone diisocyanate are charged and reacted at 90 ° C. for 10 hours under a nitrogen stream to urethane having an isocyanate group content of 2.84% by mass. After producing the prepolymer, 66 parts of ethyl acetate was added thereto to prepare a uniform solution of urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 7.25 parts of isophorone diamine, 0.27 parts of di-n-butylamine, 131 parts of ethyl acetate and 106 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours. To obtain a polyurethane resin solution a1-2. The obtained polyurethane resin solution a1-2 had a resin solid content concentration of 30.1% by mass and a weight average molecular weight of the resin solid content of 30,000.

(Synthesis Example 3) a1-3
90 parts of polyester polyol (hydroxyl value: 20 mgKOH / g) and 10 parts of polyethylene glycol (hydroxyl value: 20 mgKOH / g) made from neopentyl glycol and adipic acid in a four-necked flask equipped with a stirrer, thermometer, recirculation cooler and nitrogen gas introduction tube. A hydroxyl value: 56 mgKOH / g) and 14.2 parts of isophorone diisocyanate were charged and reacted at 90 ° C. for 10 hours under a nitrogen stream to produce a urethane prepolymer having an isocyanate group content of 3.08% by mass, and then acetic acid was added thereto. 61.5 parts of ethyl was added to make a uniform solution of urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 7.09 parts of isophorone diamine, 0.92 parts of di-n-butylamine, 124 parts of ethyl acetate and 100 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours. To obtain a polyurethane resin solution a1-3. The obtained polyurethane resin solution a1-3 had a resin solid content concentration of 30.0% by mass and a weight average molecular weight of the resin solid content of 60,000.

[Synthesis of polyurethane resin (a2)]
(Synthesis Example 4) a2-1
100 parts of polyester polyol (hydroxyl value: 108 mgKOH / g) made from neopentyl glycol and sebacic acid and isophorone diisocyanate 32.3 in a four-necked flask equipped with a stirrer, thermometer, recirculation cooler and nitrogen gas introduction tube. Parts are charged and reacted at 90 ° C. for 10 hours under a nitrogen stream to produce a urethane prepolymer having an isocyanate group content of 3.08% by mass, and then 71.2 parts of ethyl acetate is added thereto to make the urethane prepolymer uniform. It was made into a solution. Next, the urethane prepolymer solution was added to a mixture consisting of 8.47 parts of isophorone diamine, 0.46 parts of di-n-butylamine, 143 parts of ethyl acetate and 115 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours. To obtain a polyurethane resin solution a2-1. The obtained polyurethane resin solution a2-1 had a resin solid content concentration of 29.9% by mass and a weight average molecular weight of the resin solid content of 54,000.

(Synthesis Example 5) a2-2
In a four-necked flask equipped with a stirrer, a thermometer, a recirculation cooler and a nitrogen gas introduction tube, 100 parts of a polyester polyol (hydroxyl value: 122 mgKOH / g) made from neopentyl glycol and dimer acid and hexamethylene diisocyanate 26. Three parts were charged and reacted at 90 ° C. for 10 hours under a nitrogen stream to produce a urethane prepolymer having an isocyanate group content of 3.07% by mass, and then 68 parts of ethyl acetate was added thereto to form a uniform solution of the urethane prepolymer. And said. Next, the urethane prepolymer solution was added to a mixture consisting of 8.09 parts of isophorone diamine, 0.38 parts of di-n-butylamine, 136 parts of ethyl acetate and 110 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours. To obtain a polyurethane resin solution a2-2. The obtained polyurethane resin solution a2-2 had a resin solid content concentration of 30.1% by mass and a weight average molecular weight of the resin solid content of 48,000.

(Synthesis Example 6) a2-3
90 parts of polyester polyol (hydroxyl value: 20 mgKOH / g) and 10 parts of polyethylene glycol (hydroxyl value: 20 mgKOH / g) made from neopentyl glycol and sebacic acid in a four-necked flask equipped with a stirrer, thermometer, recirculation cooler and nitrogen gas introduction tube. A hydroxyl value: 56 mgKOH / g) and 14.2 parts of isophorone diisocyanate were charged and reacted at 90 ° C. for 10 hours under a nitrogen stream to produce a urethane prepolymer having an isocyanate group content of 3.08% by mass, and then acetic acid was added thereto. 61.5 parts of ethyl was added to make a uniform solution of urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 7.09 parts of isophorone diamine, 0.92 parts of di-n-butylamine, 124 parts of ethyl acetate and 100 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours. To obtain a polyurethane resin solution a2-3. The obtained polyurethane resin solution a2-3 had a resin solid content concentration of 30.0% by mass and a weight average molecular weight of the resin solid content of 60,000.

(Preparation of vinyl chloride vinyl acetate copolymer resin solution)
Vinyl chloride vinyl acetate copolymer resin having a hydroxyl group (resin monomer composition is vinyl chloride / vinyl acetate / vinyl alcohol = 92/3/5, hydroxyl value (mgKOH) = 64) is acetic acid. A 15% solution was prepared with ethyl, and this was used as a vinyl chloride vinyl acetate copolymer resin solution (B-1).

[Example 1]
6 parts of the obtained polyurethane resin solution a1-1, 24 parts of the polyurethane resin solution a2-1, 30 parts of vinyl chloride vinyl acetate copolymer resin solution A-1 having a hydroxyl group (15% solution), 10 phthalocyanine blue pigments A total of 100 parts of a mixture of parts (FASTGEN Blue LA5380 manufactured by DIC Co., Ltd.), 27 parts of ethyl acetate, and 3 parts of water was kneaded to prepare an indigo printing ink.

[Evaluation item 1: Adhesion to various films]
The viscosity of the obtained indigo printing ink was adjusted to 16 seconds (25 ° C.) with Zahn Cup # 3 (manufactured by Rigosha) with a mixed solvent of ethyl acetate / isopropyl alcohol = 50/50 (mass ratio), and the plate depth was 35 μm. Biaxially stretched polyester film U (hereinafter referred to as PET film, Toyo Spinning Co., Ltd.) in which various barrier films (W, X, Y, Z) are corona-treated on the vapor-deposited side and one side by a gravure calibrator equipped with a gravure plate. E-5100 made by the company (12 μm thickness) and biaxially stretched polypropylene film V (hereinafter, OPP film, P2161 made by Toyo Spinning Co., Ltd., P2161 thickness 20 μm) are printed on the corona-treated surface side, and the printed matter is left for one day before printing. A cellophane tape (12 mm width made by Nichiban) was attached to the surface, and the appearance of the printed film when the tape was rapidly peeled off was visually judged in the following five stages.
5: The print film did not peel off at all.
4: More than 70% to less than 90% of the printed film remained on the film.
3: More than 50% to less than 70% of the printed film remained on the film.
2: More than 30% to less than 50% of the printed film remained on the film.
1: The print film remained less than 30%.
Barrier film to be evaluated W: Alumina vapor deposition transparent PET film manufactured by Dai Nippon Printing Co., Ltd. IB-PET-PUB (thickness: 12 μm)
X: Silica-deposited transparent PET film manufactured by Mitsubishi Plastics Co., Ltd. Tech Barrier TX-R (thickness: 12 μm)
Y: Silica-deposited transparent PET film made by Oike Kogyo Co., Ltd. MOS-TEB (thickness: 12 μm)
Z: Toppan Printing Co., Ltd. Aluminum oxide thin-film transparent PET film GL-ARH (thickness: 12 μm)

[Evaluation item 2: Blocking resistance]
The films were overlapped so that the printed surface and the non-printed surface of the same printed matter produced by the adhesion to various films of Evaluation Item 1 were in contact with each other, and ^{a load of 10 kgf / cm 2} was applied for 12 hours in an environment of 40 ° C. After aging and taking out, the state of ink transfer to the non-printed surface was visually evaluated in the following three stages.
◯: No transfer is observed when the amount of ink transferred to the non-printed surface is 0% Δ: Less than 20% of the transfer is observed ×: 20% or more of the transfer amount is transferred

[Examples 1 to 30, Comparative Examples 1 to 6]
Using the polyurethane resins obtained in Synthesis Examples 1 to 6, inks were prepared in the same procedure as in Example 1 by blending the compositions of Examples 1 to 30 and Comparative Examples 1 to 6. The composition composition and results are shown in Tables 2 to 7.

The liquid ink composition of the present invention has both adhesion to various functional film substrates and blocking resistance after printing.

The liquid ink composition of the present invention can be widely applied to industrial products such as food packaging materials, sanitary products, cosmetics, and electronic parts, for which demand for a wide variety of film configurations is expected.

Claims (12)

1. A liquid ink composition containing a polyurethane resin (A) and a vinyl chloride vinyl acetate copolymer resin (B) having a hydroxyl group, wherein the polyurethane resin (A) has two or more carboxyl groups having 6 or less carbon atoms. A polyurethane resin (a1) using a polycarboxylic acid having a reaction raw material and a polyurethane resin (a2) using a polycarboxylic acid having 7 or more carbon atoms and having two or more carboxyl groups as a reaction raw material can be used in combination. A characteristic liquid ink composition.
2. The first aspect of claim 1, wherein the mass ratio of the polyurethane resin (a1) to the polyurethane resin (a2) is in the range of (a1) / (a2) = 5/95 to (a1) / (a2) = 95/5. Liquid ink composition.
3. The liquid ink composition according to claim 1 or 2, further containing water in an amount of less than 10% by mass based on the total amount of the composition.
4. Claims 1 to 3 in which the polyurethane resin (a1) or the polyurethane resin (a2) further uses a polyether polyol as a reaction raw material, and the mass ratio of the polyether polyol is 1 to 40% by mass of the total amount of the polyurethane resin (A). The liquid ink composition according to any one of.
5. The liquid ink according to any one of claims 1 to 4, wherein the polyurethane resin (a1) or the polyurethane resin (a2) further uses a polyether polyol as a reaction raw material, and the polyether polyol has a number average molecular weight of 100 to 3500. Composition.
6. The liquid ink composition according to any one of claims 1 to 5, further comprising a colorant (C) and an organic solvent (D).
7. The polycarboxylic acid having 6 or less carbon atoms and having two or more carboxyl groups is any one of succinic acid, succinic anhydride, adipic acid, or a mixture thereof, according to any one of claims 1 to 6. The liquid ink composition described.
8. The liquid ink composition according to any one of claims 1 to 7, wherein the polycarboxylic acid having 7 or more carbon atoms and having 2 or more carboxyl groups is sebacic acid, dimer acid, or a mixture thereof.
9. The vinyl chloride vinyl acetate copolymer resin (B) has a hydroxyl group, the hydroxyl value thereof is 50 to 200 mg equivalent KOH, and the content of the vinyl chloride component in the copolymer resin is 80 to 95% by mass. The liquid ink composition according to any one of claims 1 to 8.
10. The liquid ink composition according to any one of claims 1 to 9, wherein the organic solvent (D) does not contain an aromatic organic solvent and / or a ketone solvent.
11. A printed matter obtained by printing the liquid ink composition according to any one of claims 1 to 10.
12. A laminated laminate made of the printed matter according to claim 11.