TW201925378A - Aqueous liquid ink and printed article - Google Patents

Abstract

The present invention addresses the problem of providing an aqueous liquid ink which exhibits adhesion to a base material, blocking resistance, redissolution properties, and a high printing density, and which is also capable of achieving high water resistance (boil retort properties). This aqueous liquid ink includes a colouring agent (A), a binder (B) having acid groups, a basic compound (C), and an aqueous medium (D). The binder (B) having acid groups includes a urethane resin (B1) which is a reaction product of a polyisocyanate (b2), and a polyol (b1) including a polyol (b1-1) having acid groups and a polyether polyol (b1-2). The content of alicyclic structures included in the urethane resin (B1) is in the range of 1,000-5,000 mmol/kg inclusive. The basic compound (C) includes a basic metal compound (C1) and an organic amine (C2).

Description

   Water-based liquid ink and printed matter   

The present invention relates to an aqueous liquid ink that can be used for water-based printing and a printed matter that is printed by using the aqueous liquid ink.

Gravure printing and flexographic printing are widely used for the purpose of giving decorativeness and functionality to the printed matter. In recent years, in the printing ink industry, as a means to solve the hazards such as air pollution caused by solvent-based printing inks, occupational safety and health such as organic solvent poisoning, and even fire and explosion hazards, further The requirements for the replacement of water-based printing inks for positions such as safety and hygiene, environmental protection, and reduction of residual solvents in packaging materials are increasing. In fact, water-based printing inks are gradually being widely used in the printing of general packaging paper, corrugated paper and other paper containers.

As an example of such water-based printing inks, there is proposed a surface-printing water-based printing ink for packaging which is obtained by reacting a polyamide compound and a polyamine compound other than the polyamide compound in a polymer containing an isocyanate group The organic solvent solution of the polyurethane resin is neutralized with deionized water containing ammonia, thereby making the water-melted aqueous polyurethane resin a binder (for example, refer to Patent Document 1: Japanese Patent Laid-Open No. 8-53641).

Furthermore, a water-based printing ink composition for lamination using an aqueous polyurethane resin is proposed, in which the aqueous polyurethane resin is composed of an organic diisocyanate compound and a specific polycarbonate diol. After the polymer diol compound and the chain extender are reacted and obtained, water and trimethylamine are added to make it aqueous (for example, refer to Patent Document 2: Japanese Patent Laid-Open No. 5-171091).

Prior technical literature Patent Literature

Patent Literature 1 Japanese Patent Laid-Open No. 8-53641

Patent Document 2 Japanese Patent Laid-Open No. 5-171091

However, if the water-based printing ink dries slower than the solvent-based printing ink, in addition to the basic performance of the adhesion to the plastic substrate, anti-blocking (anti-blocking), it must also have pigment dispersion The resolubility of the ink film that has been dried on the gravure printing plate can be dissolved by the water-based printing ink again. On the basis of having these, it is difficult to increase the printing density. For example, the water-based ink for printing on the surface of packaging described in Patent Document 1 may have insufficient anti-sticking properties and re-solubility. In addition, the laminated water-based printing ink composition described in Patent Document 2 may have insufficient resolubility, and in particular may not be said to be able to withstand long-term printing.

The present invention has been completed in view of the foregoing, and its object is to provide a substrate which has adhesion to the substrate, anti-sticking property, re-solubility, high printing density, and can also take into account high water resistance (boiling high temperature sterilization ( boil retort) aqueous liquid ink composition. By having the above-mentioned performance, it is possible to provide a printed matter that can withstand boiling and high-temperature sterilization even when used as an aqueous liquid printing ink (especially, an aqueous liquid printing ink for lamination printing of packaging materials).

In order to solve the above-mentioned problems, the present inventors have devoted themselves to the study and found that by using a binder for water-based flexographic printing ink containing a urethane resin, the urethane resin contains an alkali metal The basic compound of the compound and the organic amine neutralizes the acid group of the urethane resin that the urethane resin has, and solves the aforementioned problems, thereby completing the present invention.

That is, the present invention relates to an aqueous liquid printing ink, which is an aqueous liquid printing ink containing a colorant (A), a binder having an acid group (B), a basic compound (C), and an aqueous medium (D), It is characterized in that the aforementioned binder (B) having an acid group contains a urethane resin (B1) which is a reactant of a polyol (b1) and a polyisocyanate (b2), and the polyol (b1) contains The polyhydric alcohol (b1-1) having an acid group and the polyether polyol (b1-2) are contained in the urethane resin (B1) in the total amount of the urethane resin (B1) The content of the alicyclic structure is 1,000 mmol / kg or more and 5,000 mmol / kg or less. The aforementioned basic compound (C) includes an alkaline metal compound (C1) and an organic amine (C2).

According to the present invention, it is possible to provide an aqueous liquid printing ink which not only has adhesiveness, anti-sticking property, resolubility, high printing density, but also has high water resistance (boiling high-temperature sterilization).

Forms for carrying out the invention

The aqueous liquid printing ink of the present invention includes a colorant (A), a binder having an acid group (B), a basic compound (C), and an aqueous medium (D).

As the colorant (A), one kind or two or more kinds may be used, and pigments and dyes such as organic pigments and inorganic pigments may be mentioned, and those which can be used for printing inks, paints, and recording agents are preferred.

Examples of the aforementioned organic pigments include azo-based, phthalocyanine-based, anthraquinone-based, perylene-based, perinone-based, quinacridone-based, thioindigo-based, and Series, isoindolinone series, quinoline yellow series, methylimine azo series, diketopyrrolopyrrole (diketopyrrolopyrrole) series, isoindolin series pigments.

Examples of the inorganic pigments include carbon black, titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, erythron, aluminum, and mica. In addition, based on the use of glass flakes or bulk flakes as the base material, glittering pigments coated with metal or metal oxides (METASHINE; Nippon Sheet Glass Co., Ltd.) can be used.

As color index names, CIPigment Yellow 1, 3, 12, 13, 14, 17, 42, 74, 83; CIPigment Orange 16; CIPigment Red 5, 22, 38, 48: 1, 48: 2, 48: 4, 49: 1, 53: 1, 57: 1, 63: 1, 81, 101; CIPigment Violet 19, 23; CIPigment Blue 23, 15: 1, 15: 3, 15: 4, 17: 1, 18, 27, 29 CIPigment Green 7, 36, 58, 59; CIPigment Black 7; CIPigment White 4, 6, 18, etc.

For blue printing ink, CIPigment Blue 15: 3 (copper phthalocyanine) is preferred; for yellow printing ink, CIPigment Yellow 83 is preferred from the viewpoint of cost and light resistance; For red ink, CIPigment Red 57: 1 is preferred. From the point of view of cost and coloring power, titanium oxide is preferred for white ink; carbon black is preferred for black ink; and gold and silver ink are preferred for gold ink Aluminum is used; for pearl printing ink, mica is preferably used. Although aluminum is powder or paste, from the viewpoint of handling and safety, it is preferable to use paste, and whether to use a floating type or a non-leafing type depends on the sense of brightness and The point of concentration is appropriately selected.

The total content of the aforementioned pigments is preferably 1% by mass or more and preferably 50% by mass or less in the total amount of the printing ink from the viewpoint of ensuring the concentration and coloring power of the printing ink.

The aforementioned binder (B) having an acid group contains a urethane resin (B1) which is a reactant of a polyol (b1) and a polyisocyanate (b2), and the polyol (b1) contains a polyol having an acid group (b1-1) and polyether polyol (b1-2).

The acid value of the aforementioned urethane resin (B1) is preferably 3 mgKOH / g or more, more preferably 5 mgKOH / g or more, and preferably 40 mgKOH / g or less, and more preferably 25 mgKOH / g or less. In this specification, the acid value means the calculated amount based on the usage amount of the acid group-containing compound such as the acid group-containing polyol (b1-1) used in the production of the urethane resin (B1). Theoretical value.

Moreover, the said urethane resin (B1) contains an alicyclic structure. By including an alicyclic structure, blocking of printed matter can be suppressed. Examples of the alicyclic structure include, for example, cyclobutane ring, cyclopentane ring, cyclohexyl ring, cycloheptane ring, cyclooctyl ring, propylcyclohexyl ring, etc., having 3 to 10 carbon atoms (preferably the number of carbon atoms 4 or more and 8 or less) saturated monocyclic structure; tricyclic [5.2.1.0 ^2,6 ] decyl skeleton, bicyclic [4.3.0] nonyl skeleton, tricyclic [5.3.1.1] dodecyl skeleton, propyl Tricyclic [5.3.1.1] twelve base skeleton, drop Saturated bridged ring structures with carbon atoms of 5 or more and 20 or less (preferably 7 or more and 12 or less carbon atoms), such as a base skeleton, isocamphenyl skeleton, dicyclopentyl skeleton, and adamantyl skeleton. Among these, a saturated monocyclic structure is preferable, and a cyclohexyl ring structure is more preferable.

In the total amount of the urethane resin (B1), the content of the alicyclic structure contained in the urethane resin (B1) is 1,000 mmol / kg or more, preferably 1,300 mmol / kg or more, More preferably, it is 1,800 mmol / kg or more and 5,000 mmol / kg or less, preferably 3,000 mmol / kg or less, and more preferably 2,500 mmol / kg or less.

In this specification, the ratio of the alicyclic structure contained in the urethane resin (B1) is based on the polyol (b1) and polyisocyanate used in the production of the urethane resin (B1) ( b2) The total mass of all raw materials, etc., and the compound containing an alicyclic structure used in the production of the aforementioned urethane resin (A) (polyol having an alicyclic structure (b1-3), having an alicyclic structure The calculated value of the mass of the alicyclic structure of the polyisocyanate.

The alicyclic structure may be included in the polyol (b1), or may be included in the polyisocyanate (b2). The content ratio of the alicyclic structure derived from the polyisocyanate (b2) to the alicyclic structure derived from the polyol (b1) is 0 or more, preferably 0.05 or more, and more preferably 0.1 on a molar basis. Above, it is more preferably 0.2 or more, and preferably 10 or less, more preferably 8 or less, and still more preferably 5 or less.

Examples of the acid group of the acid group-containing polyol (b1-1) include a carboxyl group or a sulfonic acid group, and examples of the acid group-containing polyol (b1-1) include a carboxyl group polyol , Polyols with sulfonic acid groups, etc.

As the polyol having a carboxyl group, one kind or two or more kinds can be used, and examples thereof include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, and 2,2-dimethylolmethyl. Hydroxy acids such as glycyrrhetinic acid; polyester polyols with carboxyl groups, etc. The polyester polyol having a carboxyl group can be obtained by reacting the hydroxy acid with various polycarboxylic acids.

As the polyol having a sulfonic acid group, one kind or two or more kinds can be used, and examples thereof include dicarboxylic acids having a sulfonic acid group or salts thereof, and low molecular weight polyols (for example, having a molecular weight of 100 or more and 1000 or less). The polyester polyol of the reactant, etc. Examples of the dicarboxylic acid having a sulfonic acid group include 5-sulfonic acid isophthalic acid, sulfonic acid terephthalic acid, 4-sulfonic acid phthalic acid, and 5- (4-sulfonic acid phenoxy ) Isophthalic acid, etc. Examples of the low-molecular-weight polyols include, for example, alkanediols having 1 to 10 carbon atoms, such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol; Diethylene glycol and other polyether polyols with 2 to 10 carbon atoms.

The number average molecular weight of the acid group-containing polyol (b1-1) is preferably 100 or more, and preferably 2000 or less, and more preferably 1000 or less.

In this specification, the number-average molecular weight and the weight-average molecular weight are the polystyrene conversion values measured by the gel permeation chromatography (GPC) method.

Examples of the polyether polyol (b1-2) include, for example, one or more compounds having two or more groups (-NH- or -OH) having active hydrogen atoms as an initiator, and Addition polymer of alkylene oxide.

Examples of the starter include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, and 1, Compounds having two hydroxyl groups such as 6-hexanediol and bisphenol A; compounds having three hydroxyl groups such as glycerin, tris (hydroxymethyl) ethane and trimethylolpropane.

Examples of the alkylene oxide include epoxide compounds such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, and epichlorohydrin; and tetrahydrofuran and other carbon atoms having 4 or more carbon atoms (preferably carbon atoms The number is 4 ~ 6, especially the cyclic ether with carbon number 4).

The number average molecular weight of the polyether polyol is preferably 500 or more, more preferably 1,000 or more, and preferably 4,000 or less, more preferably 3,000 or less from the viewpoint of compatibility with pigments and the like.

In this specification, the number average molecular weight is the value measured by the gel permeation chromatography (GPC) method.

In the polyol (b1), the total content of the acid group-containing polyol (b1-1) and the polyether polyol (b1-2) is preferably 60% by mass or more, and more preferably 75% by mass or more It is more preferably 80% by mass or more, even more preferably 90% by mass or more, and 95% by mass or less.

The aforementioned polyol (b1) is more preferably a polyol (b1-3) having an alicyclic structure.

As the polyol (b1-3) having an alicyclic structure, one or more types can be used, and examples thereof include cyclobutanediol, cyclopentanediol, 1,4-cyclohexanediol, and cycloheptanediol. , Cyclooctanediol, butylcyclohexanediol, cyclohexanedimethanol, hydroxypropylcyclohexanol, dicyclohexanediol, hydrogenated bisphenol A, 1,3-adamantanediol, etc. Structured saturated diol; unsaturated diol with alicyclic structure such as 1,1'-biscyclohexylene glycol; saturated triol with alicyclic structure such as cyclohexane triol. The number average molecular weight of the polyol (b1-3) having an alicyclic structure is preferably 100 or more and 500 or less.

In the case of using the aforementioned polyol (b1-3) having an alicyclic structure, from the viewpoint of suppressing adhesion of printed matter, the content of the polyol (b1) is preferably 0% by mass or more, and more It is preferably 5% by mass or more, and preferably 40% by mass or less, preferably 25% by mass or less, more preferably 20% by mass or less, and still more preferably 10% by mass or less.

In the polyol (b1), the total content of the polyol having an acid group (b1-1), the polyether polyol (b1-2) and the polyol having an alicyclic structure (b1-3) is It is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

As the aforementioned polyol (b1), other polyols (b1-4) may be included. Examples of the aforementioned other polyols include polyester polyols, low molecular weight polyols (for example, molecular weights of 50 or more and 300 or less), polycarbonate polyols, polyolefin polyols, and the like.

Examples of the polyester polyols include polyester polyols obtained by esterification of a low-molecular-weight polyol (for example, a polyol with a molecular weight of 50 or more and 300 or less) and a polycarboxylic acid; Polyester polyols obtained by ring-opening polymerization of ester-like compounds; such copolymerized polyester polyols, etc.

Examples of the aforementioned low molecular weight polyols include ethylene glycol, diethylene glycol, 1,2-propanediol, dipropylene glycol, neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanediol, 1,6-hexanediol, cyclohexanediol Polyols of lower molecular weight (e.g., molecular weight of 50 or more and 300 or less) such as methanol.

Examples of the aforementioned polycarboxylic acids include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid; terephthalic acid, isophthalic acid, phthalic acid, and naphthalene dicarboxylic acid. Such as aromatic polycarboxylic acids; and anhydrides or ester-forming derivatives of the aforementioned aliphatic polycarboxylic acids and aromatic polycarboxylic acids.

As the low-molecular-weight polyol, polyols having a molecular weight of about 50 or more and about 300 or less can be used, and examples thereof include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, and 1,6- Hexanediol, 3-methyl-1,5-pentanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol and other aliphatic polyols with a carbon number of 2 or more and 6 or less ; Polyols containing an alicyclic structure such as 1,4-cyclohexanediol and cyclohexanedimethanol; bisphenol compounds such as bisphenol A and bisphenol F and these alkylene oxide adducts containing an aromatic structure Of polyols, etc.

Examples of the polycarbonate polyols include reactants of carbonate and polyol; reactants of phosgene and bisphenol A, and the like.

Examples of the carbonates include methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclic carbonate, and diphenyl carbonate.

Examples of the polyol that can react with the carbonate include the polyols exemplified as the above-mentioned low molecular weight polyols; polyether polyols (polyethylene glycol, polypropylene glycol, etc.), polyester polyols (polyhexamethylene) High molecular weight polyols (such as adipic acid, etc.) (weight average molecular weight of 500 or more and 5,000 or less), etc.

Examples of the polyolefin polyol include polyisobutylene polyol, hydrogenated (hydrogenated) polybutadiene polyol, and hydrogenated (hydrogenated) polyisoprene polyol.

In the polyol (b1), the content of the other polyol (b1-4) is preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, and still more preferably 20% by mass % Or less, particularly preferably 10% by mass or less.

In particular, in the polyol (b1), the content of the polyester polyol is preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 3% by mass or less, and particularly preferably 1% by mass or less.

As the polyisocyanate (b2), one or more types can be used, and examples include 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, and carbodiimide modification Diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, phenylenediisocyanate, tolyl diisocyanate, naphthalene diisocyanate, stubble diisocyanate, tetramethyl stubble diisocyanate, etc. Aromatic polyisocyanate; aliphatic polyisocyanate such as hexamethylene diisocyanate, urethane diisocyanate; cyclohexane diisocyanate, hydrogenated stubble diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, etc. Alicyclic polyisocyanate, etc.

As the polyisocyanate (b2), it is preferable to include a polyisocyanate having an alicyclic structure. In the aforementioned polyisocyanate (b2), the content of the polyisocyanate having an alicyclic structure is preferably 50% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and preferably 100% by mass the following.

The equivalent ratio of the isocyanate group of the polyisocyanate (b2) to the hydroxyl group contained in the polyol (b1) [isocyanate group / hydroxyl group] is preferably 0.8 or more, more preferably 0.9 or more, on a molar basis. It is preferably 2.5 or less, more preferably 2.0 or less, and still more preferably 1.5 or less.

When manufacturing the urethane resin (B1), a chain extender may be used as necessary.

As the chain extender, one kind or two or more kinds can be used, and examples thereof include polyamines, hydrazine compounds, and other compounds having active hydrogen atoms.

Examples of the polyamines include ethylenediamine, 1,2-propanediamine, 1,6-hexanediamine, and piper. , 2,5-Dimethylpiper , Isophorone diamine, 4,4'-dicyclohexylmethanediamine, 3,3'-dimethyl-4,4'-dicyclohexylmethanediamine, 1,4-cyclohexanediamine, Diamines such as N-ethylaminoethylamine, N-methylaminopropylamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropyl Diamines with hydroxyl groups such as aminopropylamine; triamines such as diethylenetriamine and dipropylenetriamine; tetraamines such as triethylenetetramine. Among these, ethylenediamine is preferred.

Examples of the hydrazine compound include hydrazine, N, N′-dimethylhydrazine, 1,6-hexamethylenebishydrazine, succinic acid dihydrazide, adipic acid dihydrazide, glutaric acid dihydrazide , Dihydrazide sebacate, dihydrazide isophthalate, β-hemihydrazide propionate hydrazide, 3-hemihydrazide-propyl-hydrazine formate, hemihydrazine-3-hemipazhydrin A Yl-3,5,5-trimethylcyclohexane, etc.

Examples of the aforementioned other compounds having active hydrogen include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, and 1,4-butanediol. , Hexamethylene glycol, sucrose, methylene glycol, glycerol, sorbitol and other glycols; bisphenol A, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl ether, 4 , 4'-dihydroxydiphenyl sulfone, hydrogenated bisphenol A, hydroquinone and other phenols, water, etc.

As the chain extender, for example, when a polyamine is used, the equivalent ratio of the amine group and isocyanate group [amine group / isocyanate group] of the polyamine is preferably 1.2 or less, and more preferably 0.3 to 1 or less.

The weight average molecular weight of the urethane resin (A) is preferably 5,000 or more, more preferably 10,000 or more, still more preferably 20,000 or more, and preferably 500,000 or less from the viewpoint of improving the durability of the printed matter. More preferably, it is 200,000 or less, and even more preferably 100,000 or less. By increasing the weight average molecular weight, not only can the durability of the printed matter be improved, but also the sticking caused by poor drying can be suppressed. By appropriately reducing the weight average molecular weight, the transfer failure and resolubility of the ink can be suppressed. .

The urethane resin (B1) can be produced by reacting the polyol (b1) and the polyisocyanate (b2), and then reacting a chain extender as needed. When reacting the polyol (b1) and the polyisocyanate (b2), an organic solvent may coexist. The reaction temperature when the polyol (b1) and the polyisocyanate (b2) are reacted is preferably 50 ° C or more and 150 ° C or less.

As the organic solvent, one or two or more kinds can be used, and examples thereof include ketone solvents such as acetone and methyl ethyl ketone; Ether solvents such as alkane; ester solvents such as ethyl acetate and butyl acetate; nitrile solvents such as acetonitrile; amide solvents such as dimethylformamide and N-methylpyrrolidone.

In addition, in order to achieve safety and reduce the load on the environment, the organic solvent may be partially removed by vacuum distillation or the like during or after the manufacture of the urethane resin (B1). All.

In the binder (B) having an acid group, the content of the urethane resin (B1) is preferably 90% by mass or more, more preferably 95% by mass or more, and still more preferably 99% by mass or more, Tejia is 100% by mass.

The aforementioned binder (B) having an acid group may be dispersed in an aqueous medium (D) described later in advance. As a method for dispersing the urethane resin (B1) in the aqueous medium (D) (aqueous method), the aforementioned binder (B) having an acid group (preparation step of binder (B)) can be mentioned. , The obtained acid group-containing binder (B) is mixed with at least a part of the basic compound (C) described later (neutralization step), and the obtained mixture is mixed with the aforementioned aqueous medium (D) to prepare a dispersion liquid ( Dispersion step) method.

In the case of using a chain extender, the chain extender may be added in the aforementioned preparation step of the binder (B), or may be added after the aforementioned dispersion step.

The content rate of the binder (B) having an acid group is in the aforementioned dispersion liquid from the viewpoints of the resolubility of the aqueous ink, the suppression of the adhesion of the printed matter, the increase in the printing density, and the adhesion to the substrate. It is preferably 10% by mass or more, more preferably 20% by mass or more, and preferably 50% by mass or less, and more preferably 40% by mass or less.

In the aforementioned water-based method, an emulsifier may be used as necessary. In addition, when water dissolves and disperses, a machine such as a homogenizer can be used as necessary.

Examples of the emulsifier include polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene sorbitol tetraoleate, polyoxyethylene‧poly Nonionic emulsifiers such as oxypropylene copolymers; fatty acid salts such as sodium oleate, alkyl sulfate ester salts, alkylbenzene sulfonate salts, alkyl sulfonic acid succinate salts, naphthalene sulfonate salts, polyoxyethylene alkyl groups Sulfate, alkane sulfonic acid sodium salt, alkyl diphenyl ether sulfonic acid sodium salt and other anionic emulsifiers; alkyl amine salt, alkyl trimethyl ammonium salt, alkyl dimethyl benzyl ammonium salt and other cationic systems Emulsifier, etc. Among them, from the viewpoint of storage stability, an anionic or nonionic emulsifier is preferred.

The aforementioned basic compound (C) includes a basic metal compound (C1) and an organic amine (C2).

Examples of the basic metal compound (C1) include metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, and magnesium hydroxide; metal chlorides such as sodium chloride and potassium chloride; and sulfuric acid Metal sulfates such as copper.

Examples of the organic amine (C2) include ammonia; primary amines such as monoethanolamine; tertiary amines such as triethylamine and diethylethanolamine; Cyclic amines such as Porphyrin.

The ratio represented by the following formula is preferably 0.001 or more, more preferably 0.01 or more, still more preferably 0.05 or more, and 0.3 or less, preferably 0.25 or less, more preferably 0.2 or less, and still more preferably 0.15 or less. When the aforementioned ratio is within the aforementioned range, the boiling high-temperature sterilization property becomes good.

Molar number of basic metal compound (C1) × valence of basic metal compound (C1) / ((mole number of organic amine (C2) × valence of organic amine (C2)) + (basic metal compound (C1) mole number × valence of basic metal compound (C1))}

In the aqueous liquid ink, the basic metal compound (C1) and the organic amine (C2) may form a salt with the acid group of the binder (B) having an acid group. By neutralizing the acid group of the binder having an acid group with the basic compound (C1) and the organic amine (C2), it becomes easy to improve the water dispersibility.

The content of the basic compound (C) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and still more preferably 0.1 parts by mass or more with respect to 100 parts by mass of the binder (B) having an acid group. It is preferably 10 parts by mass or less, more preferably 7 parts by mass or less, and still more preferably 4 parts by mass or less.

Examples of the aqueous medium (D) include water; hydrophilic organic solvents; mixtures of water and hydrophilic organic solvents, etc. From the viewpoint of safety and environmental burden, water, or water and hydrophilicity are preferred Mixture of organic solvents.

As the hydrophilic organic solvent, one or two or more kinds may be used, and those mixed with water are preferred, and examples thereof include alcohol solvents such as methanol, ethanol, n-propanol, and 2-propanol; acetone, methyl ethyl ketone Other ketone solvents; glycol, diethylene glycol, propylene glycol, polyalkylene glycol, glycerol and other polyol solvents; propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, ethyl card Ether solvents such as bisphenol; amide solvents such as N-methyl-2-pyrrolidone, etc.

When the aqueous medium (D) contains water and a hydrophilic organic solvent, in the aqueous medium (D), the water content is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass The above is, for example, 100% by mass or less, and 95% by mass or less is also allowed.

The aqueous liquid printing ink of the present invention may further contain an auxiliary agent. As the aforementioned auxiliary agent, waxes such as paraffin wax, polyethylene wax, palm wax, etc. for imparting friction resistance, sliding properties, etc .; amide oleate, amide stearate, amide erucate, etc. can also be suitably used. Fatty acid amide compounds; silicone-based and non-silicon-based defoamers for suppressing foaming during printing; dispersants, etc.

As the dispersant, a nonionic dispersant is preferred.

The acid value of the aforementioned dispersant is preferably 30 mgKOH / g or less, more preferably 25 mgKOH / g or less, still more preferably 20 mgKOH / g or less, and for example, 1 mgKOH / g or more, and further may be 3 mgKOH / g or more.

The acid value of the dispersant is preferably smaller than the acid value of the binder (B) having an acid group. The difference between the acid value of the binder (B) having an acid group and the acid value of the dispersant is, for example, 1 mgKOH / g or more, more preferably 3 mgKOH / g or more, and preferably 30 mgKOH / g or less, more preferably 20mgKOH / g or less.

The content of the dispersant is preferably 40 parts by mass or more, more preferably 50 parts by mass or more, more preferably 60 parts by mass or more, and preferably 100 parts by mass or less with respect to 100 parts by mass of the colorant (A). It is more preferably 80 parts by mass or less, and even more preferably 75 parts by mass or less.

The content of the dispersant is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and still more preferably 30 parts by mass or more, relative to 100 parts by mass of the binder (B) having an acid group. 100 parts by mass or less, more preferably 80 parts by mass or less, and still more preferably 60 parts by mass or less.

The viscosity of the aforementioned water-based liquid printing ink, as a value measured at 25 ° C. using a Zahn Cup # 4 manufactured by Clutch Co., is preferably 7 seconds or more, more preferably 10 seconds or more, and It is preferably 25 seconds or less, and more preferably 20 seconds or less.

If the viscosity is expressed in milliPascal seconds, at 25 ° C, it is preferably 70 (mPa‧s) or more, more preferably 100 (mPa‧s) or more, and preferably 350 (mPa‧s) or less, more It is preferably less than 250 (mPa‧s).

The surface tension of the aqueous liquid printing ink is preferably 25 mN / m or more, more preferably 33 mN / m or more, and preferably 50 mN / m or less, and more preferably 43 mN / m or less. By appropriately increasing the surface tension of the printing ink, the wettability of the printing ink to the substrate can be maintained while suppressing dot bridges (in the halftone halftone dots, adjacent dots are connected to each other Dirty printing surface) By appropriately reducing the surface tension of the ink, the wettability of the ink on the substrate can be improved and shrinkage can be suppressed.

The water-based liquid printing ink of the present invention can use Eiger Mill (Eiger Mill), sand mill, Gamma Mill (Gamma Mill), attritor generally used in the manufacture of gravure and flexographic printing ink ) Etc. for manufacturing.

When preparing the aqueous liquid ink of the present invention, from the viewpoint of uniformity, at least a part of the colorant (A), the acid group-containing binder (B), and the basic compound (C ), At least a part of the dispersant, and at least a part of the aqueous medium (D) are mixed to prepare a preliminary composition (kneaded base ink).

The aqueous liquid ink system of the present invention has excellent adhesion to various substrates, and can be used for printers such as paper, synthetic paper, thermoplastic resin films, plastic products, steel plates, etc., used for electronic engraving, etc. Inks for gravure printing of gravure printing plates, or flexographic printing using flexographic printing plates made of resin plates, etc. On the other hand, it is not suitable to eject ink from inkjet nozzles without using plates Ink-jet printer. That is, in the case of inkjet ink, the ink droplets ejected from the nozzle will directly attach to the substrate to form a printed matter. In contrast, the aqueous liquid ink of the present invention temporarily attaches and transfers the printing ink After the printing plate or pattern is printed, only the ink is attached to the substrate again, and it is dried as needed to make the printed matter.

The film thickness of the printing ink formed by the gravure printing method or the flexographic printing method using the aqueous liquid ink of the present invention is, for example, 10 μm or less, preferably 5 μm or less.

The base material system includes polyamide resins such as nylon 6, nylon 66, and nylon 46; polyethylene terephthalate (PET), polyethylene naphthalate, and polypropylene terephthalate Polyester resins such as esters, polytrimethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate; polyhydroxycarboxylic acids such as polylactic acid; poly (ethylene succinate), Biodegradable resins such as aliphatic polyester resins such as poly (butylene succinate); polyolefin resins such as PP and polyethylene; thermoplastic resins such as polyimide resins, polyarylate resins or mixtures of these The formed film or these laminates, but a film made of polyester, polyamide, polyethylene, polypropylene can be preferably used. These substrate films may be unstretched films or stretched films, and the manufacturing method thereof is not limited. In addition, the thickness of the base film is not particularly limited, but it is usually sufficient if it is in the range of 1 to 500 μm.

The printed surface of the base film is preferably subjected to corona discharge treatment, and silica, alumina, or the like may also be vapor-deposited.

    [Example]    

Hereinafter, the present invention will be specifically described by Examples and Comparative Examples.

    (Synthesis Example 1: Preparation of Adhesive (1))    

195 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 145 parts by mass of isophorone diisocyanate, 2,2-dihydroxy in a container equipped with a thermometer, a nitrogen introduction tube, a stirrer and replaced with nitrogen A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 203 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 2.2 parts by mass of 50% by mass potassium hydroxide aqueous solution and 12.0 parts by mass of 25% by mass ammonia aqueous solution, part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized, and then water is added 726 parts by mass and 9.2 parts by mass of the 80% hydrazine aqueous solution were sufficiently stirred to obtain an aqueous dispersion of the urethane resin. Next, by performing aging and solvent removal, a binder with a nonvolatile content of 40% by mass was obtained. (1).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (1) is 2115 mmol / kg, and the acid value is 28 mgKOH / g.

    (Synthesis Example 2: Preparation of Adhesive (2))    

In a vessel equipped with a thermometer, a nitrogen introduction tube, a stirrer and substituted with nitrogen, 194 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 144 parts by mass of isophorone diisocyanate, 2,2-dihydroxyl A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 202 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 6.5 parts by mass of a 50% by mass potassium hydroxide aqueous solution and 9.3 parts by mass of a 25% by mass ammonia solution, a part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized and then added 727 parts by mass of water and 9.1 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred, thereby obtaining an aqueous dispersion of the urethane resin, and then, by performing aging and desolvation, a bonding of 40% by mass of the nonvolatile component was obtained. Agent (2).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (2) is 2103 mmol / kg, and the acid value is 28 mgKOH / g.

    (Synthesis Example 3: Preparation of adhesive (3))    

193 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 143 parts by mass of isophorone diisocyanate, 2,2-dihydroxy A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 201 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 10.8 parts by mass of a 50% by mass potassium hydroxide aqueous solution and 6.6 parts by mass of a 25% by mass ammonia aqueous solution, a part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized and then added 728 parts by mass of water and 9.1 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred to obtain an aqueous dispersion of the urethane resin, and then, by performing aging and desolvation, a bonding of 40% by mass of the nonvolatile component was obtained Agent (3).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (3) is 2092 mmol / kg, and the acid value is 28 mgKOH / g.

    (Synthesis Example 4: Preparation of adhesive (4))    

In a container equipped with a thermometer, a nitrogen introduction tube, a stirrer and nitrogen substitution, in polyoxytetramethylene glycol (molecular weight 2000) 192 parts by mass, isophorone diisocyanate 142 parts by mass, 2,2-dihydroxy A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 200 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 15.1 parts by mass of a 50% by mass potassium hydroxide aqueous solution and 3.9 parts by mass of a 25% by mass ammonia aqueous solution, a part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized, and then added 729 parts by mass of water and 9.0 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred, thereby obtaining an aqueous dispersion of the urethane resin, and then, by aging and desolvation, a bonding of 40% by mass of the non-volatile component was obtained. Agent (4).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (4) is 2080 mmol / kg, and the acid value is 28 mgKOH / g.

    (Synthesis Example 5: Preparation of adhesive (5))    

In a vessel equipped with a thermometer, a nitrogen introduction tube, a stirrer and substituted with nitrogen, 191 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 142 parts by mass of isophorone diisocyanate, and 2,2-dihydroxyl A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol and 199 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 19.2 parts by mass of a 50% by mass potassium hydroxide aqueous solution and 1.3 parts by mass of a 25% by mass ammonia aqueous solution, a part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized, and then added 730 parts by mass of water and 9.0 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred to obtain an aqueous dispersion of the urethane resin, and then, by performing aging and solvent removal, a bonding of 40% by mass of the nonvolatile component was obtained Agent (5).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (5) is 2069 mmol / kg, and the acid value is 28 mgKOH / g.

    (Synthesis Example 6: Preparation of Adhesive (6))    

In a container equipped with a thermometer, a nitrogen introduction tube, a stirrer and substituted with nitrogen, 269 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 102 parts by mass of isophorone diisocyanate, 2,2-dihydroxyl These mixed reactions were carried out in a mixed solvent of 24 parts by mass of methylpropionic acid, 3.5 parts by mass of neopentyl glycol, and 204 parts by mass of methyl ethyl ketone, thereby obtaining a prepolymer of carbamate having an isocyanate group at the molecular terminal Organic solvent solution of the substance (binder with acid group).

Next, by adding 2.0 parts by mass of 50% by mass potassium hydroxide aqueous solution and 10.8 parts by mass of 25% by mass aqueous ammonia solution, a part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized and then added 726 parts by mass of water and 6.4 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred, thereby obtaining an aqueous dispersion of the urethane resin, and then, by performing aging and solvent removal, a bonding of 40% by mass of the nonvolatile component was obtained Agent (6).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (6) is 1142 mmol / kg, and the acid value is 25 mgKOH / g.

    (Synthesis Example 7: Preparation of Adhesive (7))    

In a container equipped with a thermometer, a nitrogen introduction tube, and a stirrer and replaced with nitrogen, 268 parts by mass of polyoxytetramethylene glycol (molecular weight: 2000), 100 parts by mass of isophorone diisocyanate, and 2,2-dihydroxyl A mixture of 22 parts by mass of methylpropionic acid, 5.6 parts by mass of 1,4-cyclohexanedimethanol and 204 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 1.8 parts by mass of 50% by mass potassium hydroxide aqueous solution and 10.0 parts by mass of 25% by mass ammonia aqueous solution, part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized, and then added 726 parts by mass of water and 6.3 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred to obtain an aqueous dispersion of the urethane resin, and then, by performing aging and desolvation, a bonding of 40% by mass of the non-volatile component was obtained. Agent (7).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (7) is 1222 mmol / kg, and the acid value is 23 mgKOH / g.

    (Synthesis Example 8: Preparation of Adhesive (8))    

252 parts by mass of polyoxytetramethylene glycol (molecular weight: 2000), 110 parts by mass of isophorone diisocyanate, 2,2-dihydroxymethane in a container equipped with a thermometer, a nitrogen introduction tube, and a stirrer and replaced with nitrogen A mixture of 8.7 parts by mass of propionic acid, 26 parts by mass of 1,4-cyclohexanedimethanol, and 204 parts by mass of methyl ethyl ketone was used to react these to obtain an amino group having an isocyanate group at the molecular terminal. Organic solvent solution of ester prepolymer (adhesive with acid group).

Next, by adding 0.7 mass parts of 50 mass% potassium hydroxide aqueous solution and 4.0 mass parts of 25 mass% ammonia solution, a part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized and then added 726 parts by mass of water and 7.0 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred to obtain an aqueous dispersion of the urethane resin, and then, by aging and desolvation, 40% by mass of non-volatile components were bonded. Agent (8).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (8) is 1683 mmol / kg, and the acid value is 9 mgKOH / g.

    (Synthesis Example 9: Preparation of Adhesive (9))    

In a container equipped with a thermometer, a nitrogen introduction tube, a stirrer and replaced with nitrogen, 115 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 181 parts by mass of isophorone diisocyanate, 2,2-dihydroxyl A mixture of 17 parts by mass of methylpropionic acid, 85 parts by mass of 1,4-cyclohexanedimethanol, and 205 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer (binder with acid group).

Next, by adding 1.4 mass parts of 50 mass% potassium hydroxide aqueous solution and 7.9 mass parts of 25 mass% ammonia solution, part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized and then added 727 parts by mass of water and 2.2 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred, thereby obtaining an aqueous dispersion of the urethane resin, and then, by aging and desolvation, 40% by mass of the non-volatile component was bonded. Agent (9).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (9) is 3511 mmol / kg, and the acid value is 18 mgKOH / g.

    (Comparative Synthesis Example 1: Preparation of binder (10))    

196 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 145 parts by mass of isophorone diisocyanate, 2,2-dihydroxy A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 204 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer.

Next, by adding 13.3 parts by mass of a 25% by mass aqueous ammonia solution, part or all of the carboxyl groups of the aforementioned carbamate prepolymer were neutralized, and then 725 parts by mass of water and 9.2 parts by mass of an 80% hydrazine aqueous solution were added. The mixture was stirred well to obtain an aqueous dispersion of the urethane resin, and then, by aging and solvent removal, a binder (10) having a nonvolatile content of 40% by mass was obtained.

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (10) is 2120 mmol / kg, and the acid value is 28 mgKOH / g.

    (Comparative Synthesis Example 2: Preparation of Adhesive (11))    

196 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 145 parts by mass of isophorone diisocyanate, 2,2-dihydroxy A mixture of 26 parts by mass of methylpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 204 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer.

Next, by adding 20 parts by mass of triethylamine, part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized, and then 725 parts by mass of water and 9.2 parts by mass of an 80% hydrazine aqueous solution are added. With sufficient stirring, an aqueous dispersion of the urethane resin was obtained, followed by aging and solvent removal to obtain a binder (11) having a nonvolatile content of 40% by mass.

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (11) is 2120 mmol / kg, and the acid value is 28 mgKOH / g.

    (Comparative Synthesis Example 3: Preparation of binder (12))    

In a container equipped with a thermometer, a nitrogen introduction tube, a stirrer and substituted with nitrogen, 191 parts by mass of polyoxytetramethylene glycol (molecular weight: 2000), 141 parts by mass of isophorone diisocyanate, and 2,2-dihydroxyl A mixture of 26 parts by mass of methylpropionic acid, 27 parts by mass of 1,4-cyclohexanedimethanol, and 198 parts by mass of methyl ethyl ketone was used to react these to obtain an amine group having an isocyanate group at the molecular terminal. Organic solvent solution of formate prepolymer.

Next, by adding 21.3 parts by mass of a 50% by mass potassium hydroxide aqueous solution, part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized, and then 730 parts by mass of water and an 80% hydrazine aqueous solution are added 8.9 parts by mass and sufficiently stirred to obtain an aqueous dispersion of the urethane resin, followed by aging and solvent removal to obtain a binder (12) having a nonvolatile content of 40% by mass.

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (12) is 2064 mmol / kg, and the acid value is 28 mgKOH / g.

    (Comparative Synthesis Example 4: Preparation of adhesive (13))    

In a container equipped with a thermometer, a nitrogen introduction tube, a stirrer and substituted with nitrogen, 296 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 82 parts by mass of isophorone diisocyanate, 2,2-dihydroxy 17 parts by mass of methyl propionic acid, 3.6 parts by mass of neopentyl glycol, and 205 parts by mass of methyl ethyl ketone are reacted in a mixed solvent, thereby obtaining a preform of amino formate having an isocyanate group at the molecular terminal Organic solvent solution of the polymer.

Next, by adding 1.4 parts by mass of 50% by mass potassium hydroxide aqueous solution and 7.6 parts by mass of 25% by mass aqueous ammonia solution, part or all of the carboxyl groups of the aforementioned carbamate prepolymer are neutralized and then added 727 parts by mass of water and 3.4 parts by mass of 80% hydrazine aqueous solution were sufficiently stirred to obtain an aqueous dispersion of the urethane resin, and then, by aging and desolvation, a bonding of 40% by mass of the nonvolatile component was obtained Agent (13).

The ratio of the alicyclic structure in the aforementioned urethane resin in this binder (13) is 917 mmol / kg, and the acid value is 17 mgKOH / g.

    Examples 1-9, Comparative Examples 1-4    

After the binders (1) to (13) obtained in Synthesis Examples 1 to 9 and Comparative Synthesis Examples 1 to 4 were sufficiently stirred and mixed by the following composition, they were kneaded with a bead mill to produce a kneaded base ink . Next, 10 parts by mass of each of the binders (1) to (13) and 4 parts by mass of water are added to the obtained mixed base printing ink to prepare a water-based blue printing ink. Using viscosity cup # 4 (manufactured by Clutch Co., Ltd.), the viscosity of the obtained printing ink was adjusted to 16 seconds (25 ° C.) with water, and the water was used as Examples 1-9 and Comparative Examples 1-4 respectively Liquid ink.

In addition, in order to confirm the surface tension of the obtained aqueous liquid ink, the surface tension at 25 ° C was measured. The surface tension system is based on the Whithelmy method and is measured using the automatic surface tension meter DY-300 manufactured by Kyowa Interface Science Co., Ltd.

    [Mixed base printing ink blending]    

    [Total amount of water-based liquid ink (blue) blended (excluding viscosity adjustment water)]    

The aqueous liquid printing inks of Examples 1 to 9 and Comparative Examples 1 to 4 were treated with Flexoproof 100 test printing machine (Testing Machines, Inc.) and corona-treated polyethylene terephthalate shown in Table 1 Ester (PET) film (Ester E5102 made by Toyobo Co., Ltd., thickness 12 μm), corona-treated polypropylene (OPP) biaxially stretched film (PYLEN P2161 made by Toyobo Co., Ltd., thickness 20 μm), printing length 240 mm × 80 mm After the solid line pattern, dry with a dryer to obtain printed matter.

Regarding the obtained printed matter, the resolubility, anti-sticking property, and substrate adhesion of each film were evaluated, and the ink transfer property was confirmed by the printing density.

    [Evaluation item 1: boiling high-temperature sterilization (hot water resistance)]    

On the ink surface of the corona-treated polyethylene terephthalate (PET) film printed matter, apply a dry laminating adhesive of the urethane system DICDRY LX-500 / KW-75 (manufactured by DIC) to apply After coating and drying so that the film amount became 3.5 g / m ² , the aluminum foil (hereinafter, AL: aluminum foil C made by Toyo Aluminum Industry Co., Ltd., 15 μm) was laminated by a dry laminator (made by DIC ENGINEERING) to obtain 2-layer laminate 1. Next, an adhesive was applied to the AL of the laminate 1 in the same manner, and a non-stretched polypropylene film (hereinafter, R-CPP: ZK-75 50 μm manufactured by Toray Synthetic Film Co., Ltd.) was laminated and cured at 40 ° C. for 5 days. To obtain a 3-layer composite laminate 2.

The resulting laminate 2 was made into a bag with a size of 120 mm × 120 mm, and the contents were filled and sealed with 70 g of imitation food mixed with vinegar, salad oil, and meat sauce at a weight ratio of 1: 1: 1. After the prepared bag was sterilized by steam sterilization at 135 ° C for 30 minutes, the degree of peeling of the ink film was evaluated in four stages.

◎: No peeling at all.

○: There is very little peeling in small bubbles.

△: Some intermediate-sized blisters peeled off.

×: Regardless of size, there is peeling on the entire surface.

    [Evaluation Item 2: Resolubility]    

Use a syringe to drop a drop of distilled water on the ink film surface of the printed matter, and quickly wipe it off with gauze. After wiping off, the time until the coating film dissolves and disappears is measured and evaluated.

◎: After dropping, the coating film dissolves in less than 3 seconds.

○: Dissolved within 3 seconds to less than 5 seconds after dropping.

△: After dropping, it is dissolved within 5 seconds to less than 7 seconds.

×: It takes more than 7 seconds for the coating film to dissolve.

    [Evaluation Item 3: Anti-sticking property]    

Cut the film to a size of 4cm × 4cm so that the printed surface of the printed matter is in contact with the non-printed surface, overlap, apply a load of 5Kgf / cm ² , and place it under a 40 ° C environment for 12 hours. The state of the ink transfer to the non-printed surface (ink back printing) is determined visually based on the area ratio (%) of the ink back printed portion.

◎: No transfer to the non-printed surface was seen at all.

○: Although it is a small amount of less than 5%, transfer due to ink back printing is seen.

△: More than 5% to less than 20% of the transfer caused by ink back printing can be seen.

×: More than 20% of the transfer caused by ink back printing can be seen.

    [Evaluation Item 4: Substrate adhesion]    

After placing the printed matter for 1 day, attach cellophane tape (12 mm wide made by Nichiban) to the printing surface, and when the end of the cellophane tape is quickly peeled off at a right angle to the printing surface, the residual rate of the printing film is based on the area ratio. Visually judge the appearance.

◎: The printing film was not peeled off at all.

○: More than 80% to less than 90% of the printing film remains on the film.

△: More than 50% to less than 80% of the printing film remains on the film.

×: Only less than 50% of the printed film remains on the film.

    [Evaluation item 5: Ink transferability]    

The solid density of the printed matter was evaluated using a SpectroEye densitometer manufactured by X-Rite Co., Ltd. to evaluate the ink transferability.

○: The blue density of the printed matter is 1.9 or more, and the flexographic printing suitability is good.

△: The blue density of the printed matter is 1.6 or more and less than 1.9, and the suitability for flexographic printing is medium.

×: The blue density of the printed matter is less than 1.6, and the suitability for flexographic printing is poor.

By using the aqueous liquid printing ink of the present invention, it is possible to provide an aqueous solution that has adhesion to the substrate, anti-sticking property, re-solubility, high printing density, and can further take into account high water resistance (boiling high temperature sterilization) Liquid ink composition. By having both the above-mentioned properties, it is possible to provide a printed matter that is also resistant to boiling high-temperature sterilization.

Claims (6)

    An aqueous liquid printing ink, which is an aqueous liquid printing ink containing a colorant (A), an acid group-containing binder (B), an alkaline compound (C), and an aqueous medium (D), characterized in that: it has an acid The base-based adhesive (B) includes a urethane resin (B1), which is a reactant of a polyol (b1) and a polyisocyanate (b2), and the polyol ( b1) A polyol (b1-1) having an acid group and a polyether polyol (b1-2), and of the total amount of the urethane resin (B1), the urethane resin (B1 ) The content of the alicyclic structure contained is 1,000 mmol / kg or more and 5,000 mmol / kg or less. The basic compound (C) includes an alkaline metal compound (C1) and an organic amine (C2).         The aqueous liquid printing ink according to claim 1, wherein the ratio represented by the following formula is 0.3 or less, the number of moles of the basic metal compound (C1) × the valence of the basic metal compound (C1) / {(organic amine Molar number of (C2) × valence of organic amine (C2)) + (mole number of basic metal compound (C1) × valence of basic metal compound (C1))}.         The aqueous liquid printing ink according to claim 1 or 2, wherein the acid value of the binder (B) having an acid group is 3 mgKOH / g or more and 40 mgKOH / g or less.         The aqueous liquid printing ink according to any one of claims 1 to 3, wherein the polyol (b1) further contains 0 to 20% by mass of a polyol (b1-3) having an alicyclic structure.         The aqueous liquid printing ink according to any one of claims 1 to 4 has a surface tension at 25 ° C of 25 mN / m or more and 50 mN / m or less.         A printed matter characterized by being printed using the aqueous liquid printing ink according to any one of claims 1 to 5.