JPWO2021060125A1 - Aqueous liquid printing inks, printed matter, and laminates - Google Patents

Abstract

A water-based liquid printing ink containing a colorant, a binder resin, and an water-based medium, which satisfies (1) to (3). (1) The organic solvent is contained in an amount of 10% by mass or less in the total amount of the water-based liquid printing ink. (2) The aqueous medium contains water and an organic solvent (A) having a solubility in water (100 ml, 25 ° C.) of 1 to 30 (g / 100 ml). (3) The ratio of the organic solvent (A) to the other organic solvent (B) is 10:90 to 100: 0.

Description

The present invention relates to a water-based liquid printing ink such as a water-based gravure ink and a water-based flexographic ink, and a laminate using the water-based liquid printing ink.

In recent years, from the viewpoints of environmental problems, resource saving, occupational safety, disaster prevention, etc., a water-based type water-based printing ink that uses as little organic solvent as possible has been demanded. Water-based printing inks are widely used for permeable printing of general wrapping paper, coated paper, corrugated cardboard, etc., and also in the field of gravure printing on impermeable plastic film substrates mainly for packaging materials. Its use is expanding.
Compared with solvent-based printing inks that use an organic solvent as the main solvent, water-based printing inks are not yet sufficiently dry and printable on film substrates. Since water has a slow drying rate and a high surface tension, it tends to be inferior in leveling property to a non-permeable substrate such as a plastic film. Another problem is that the ink foams while the printing plate and the ink continue to come into contact with each other during printing.

Generally, a commercially available leveling agent (also referred to as a surface conditioner) is used to adjust the leveling property of the water-based printing ink on the substrate, and a defoaming agent is used to adjust the foaming. Since it remains in the film even after the ink film, it may adversely affect the physical properties of the ink film after printing. Further, when printed on a plastic film, as a water-based printing ink composition having good drying property and leveling property, and also good fine line reproducibility and net spot reproducibility, although it is a water-based ink, a water-based binder resin varnish and a pigment are used. A fluorine-containing acrylic copolymer resin obtained by copolymerizing a fluoroalkyl (meth) acrylate monomer with another polymerizable monomer is used as a solid content in an aqueous printing ink composition containing the above as a main component. , A water-based printing ink composition containing 0.01 to 5% by weight in the ink composition is known (see, for example, Patent Document 1), but this also remains in the ink film, so that the physical properties of the ink film after printing are improved. It could have an adverse effect.

Further, as an aqueous printing ink using a mixed solvent of water and alcohol, for example, the ink described in Patent Document 2 is known. However, the ink of Patent Document 2 uses a solvent in which the ratio of alcohol-based solvent to water is 50:50 to 100: 0, and has high drying property, print stability, and physical properties, and is a volatile solvent at the time of printing. The purpose of the present invention is to provide a solvent recovery and reusable printing ink that is easy to recover and can contribute to environmental protection, and the purpose of the present invention is to suppress foaming and improve the leveling property on a base material. Is completely different.

Japanese Unexamined Patent Publication No. 10-158565 WO2012 / 008339

An object of the present invention is to obtain a water-based liquid printing ink having excellent leveling property even when a small amount of organic solvent is used, no ink foaming during printing, and excellent ink film physical properties after printing, and a laminate using the water-based liquid printing ink. To provide.

The present inventors are an aqueous liquid printing ink containing a colorant, a binder resin, and an aqueous medium, and have an organic solvent (A) having a solubility in water (at 25 ° C. in 100 ml of water) of 1 to 30. ) Is designed so that the ratio of water to the organic solvent (A) is 90: 10 to 100: 0 and the content of the organic solvent (A) is 10% by mass or less in the total amount of the water-based liquid printing ink. It has been found that the water-based liquid printing ink obtained solves the above-mentioned problems.

That is, the present invention relates to an aqueous liquid printing ink containing a colorant, a binder resin, and an aqueous medium, which is characterized by satisfying (1) to (3). (1) The organic solvent is contained in an amount of 10% by mass or less in the total amount of the water-based liquid printing ink.
(2) The aqueous medium contains water and an organic solvent (A) having a solubility in water (100 ml, 25 ° C.) of 1 to 30 (g / 100 ml).
(3) The ratio of the organic solvent (A) to the other organic solvent (B) is 10:90 to 100: 0.

Furthermore, the present invention relates to an aqueous liquid printing ink in which the organic solvent (A) is 1-butanol or isobutanol.

Furthermore, the present invention relates to an aqueous liquid printing ink containing an acrylic resin or a urethane resin as the binder resin.

Furthermore, the present invention relates to a water-based liquid printing ink applied to flexographic printing or gravure printing.

Furthermore, the present invention relates to a printed matter in which the water-based liquid printing ink is printed on a substrate.

Further, the present invention relates to a laminate having one or a plurality of printing layers on a plastic film, in which at least one of the printing layers is a printing layer of the water-based liquid printing ink.

The water-based liquid printing ink of the present invention has excellent leveling properties even when a small amount of organic solvent is used, does not foam during printing, and has excellent ink film physical characteristics after printing.

The present invention will be described in detail. The "inks" used in the following description all refer to "water-based liquid printing inks". Further, "parts" mean "parts by mass", and "%" means "% by mass".
(Aqueous medium)
The water-based medium used in the water-based liquid printing ink of the present invention is a water-based medium containing water as a main component, and is characterized by satisfying the following (1) to (3).
(1) The organic solvent is contained in an amount of 10% by mass or less in the total amount of the water-based liquid printing ink.
(2) The aqueous medium contains water and an organic solvent (A) having a solubility in water (100 ml, 25 ° C.) of 1 to 30 (g / 100 ml).
(3) The ratio of the organic solvent (A) to the other organic solvent (B) is 10:90 to 100: 0.
(1) The organic solvent (A) is preferably contained in an amount of 10% by mass or less in the total amount of the water-based liquid printing ink. Among them, from the viewpoint of solubility in water, the solubility is preferably 8% by mass or less, most preferably 6% by mass or less, while the lower limit is preferably 1% by mass or more, preferably 3% by mass or more. Is still preferable.
(2) It is preferable that the aqueous medium contains water and an organic solvent (A) having a solubility in water (100 ml, 25 ° C.) of 1 to 30 (g / 100 ml).
In the present invention, the solubility in water is represented by g (grams) that dissolves in 100 ml of water at 25 ° C. Examples of the organic solvent (A) having a solubility in water at 25 ° C. of 1 to 30 include 1-butanol (solubility 6.57 g / 100 ml), isobutanol (solubility 8.5 g / 100 ml), and 1-pentanol (solubility 8.5 g / 100 ml). 2.2 g / 100 ml), 2-methyl-2-pentanol (3.24 g / 100 mL), 3-methyl-3-pentanol (4.5 g / 100 ml), methyl ethyl ketone (22.3 g / 100 ml) And so on. Of these, 1-butanol (solubility 6.57 g / 100 ml) and isobutanol (solubility 8.5 g / 100 ml) are preferable.

Two or more of these organic solvents (A) may be used in combination, if necessary.
(3) The ratio of the organic solvent (A) to the other organic solvent (B) is preferably 10:90 to 100: 0. Among them, the ratio is preferably 30:70 to 100: 0, and most preferably the ratio is 50:50 to 100: 0.

When the aqueous medium satisfies the above (1) to (3), an aqueous liquid printing ink having excellent leveling property of the present invention, no ink foaming during printing, and excellent ink film physical characteristics after printing can be obtained. Although it is not clear, it is estimated as follows.
That is, in the present invention, as defined in (2) above, an organic solvent having a slightly low solubility in water (a liquid having a solubility in water in the range of 1 to 30 is generally recognized as having low solubility) is used. By using it at a ratio of 10% or less with respect to water, there is a possibility that the surface tension is balanced and the antifoaming property is effective.
In the present invention, among others
In (1), the organic solvent (A) was contained in an amount of 8% by weight or less in the total amount of the water-based liquid printing ink.
In (2), the organic solvent (A) is 1-butanol and / or isobutanol.
In (3), a combination in which the ratio of the organic solvent (A) to the other organic solvent (B) is 30:70 to 100: 0 is still preferable.
Further, in (1), the organic solvent (A) is contained in an amount of 6% by weight or less in the total amount of the water-based liquid printing ink.
In (2), the organic solvent (A) is 1-butanol and / or isobutanol.
In (3), the combination in which the ratio of the organic solvent (A) to the other organic solvent (B) is 50:50 to 100: 0 is most preferable.

In the aqueous medium used in the present invention, the other organic solvent (B) is an organic solvent that is miscible with water having a solubility in water (100 ml, 25 ° C.) other than 1 to 30 (g / 100 ml), and is the present invention. You may use it within the range which does not impair the effect of.
Examples of the organic solvent that is completely mixed with water having a solubility in water (100 ml, 25 ° C.) of 30 (g / 100 ml) or more include methanol, ethanol, n-propyl alcohol (hereinafter, also referred to as NPA), and isopropyl alcohol. Examples thereof include monofunctional alcohols such as (hereinafter, also referred to as IPA), various diols, and polyhydric alcohols such as glycerin.
Examples of the diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, and 1,9-nonanediol. 1,10-decanediol, 1,12-dodecanediol, propylene glycol, 1,2 butanediol, 3-methyl-1,3 butanediol, 1,2pentanediol, 2-methyl-1,3propanediol, 1 , 2Hexanediol, dipropylene glycol, diethylene glycol and the like.

Further, as an aromatic diol which is an adduct of bisphenol A and an alkylene oxide having 2 or 3 carbon atoms (average addition molar number of 1 or more and 16 or less), polyoxypropylene-2,2-bis (4-hydroxyphenyl) is used. ) Propane, polyoxyethylene-2,2-bis (4-hydroxyphenyl) propane and the like.
Examples thereof include alicyclic diols such as cyclohexanediol and hydrogenated bisphenol A.
Examples of ethers include ethylene glycol monomethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, and propylene glycol monomethyl. Examples thereof include ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, ethyl carbitol and the like.
In addition, lactones such as γ-butyrolactone can also be mentioned.

Among them, methanol, ethanol, n-propyl alcohol (hereinafter, also referred to as NPA), isopropyl alcohol (hereinafter, also referred to as IPA), propylene glycol, propylene glycol monomethyl ether (1-methoxy2-propanol) (also referred to as PGM). , Ethylene glycol is preferred.

As for those having a solubility in water (100 ml, 25 ° C.) of less than 1 (g / 100 ml), for example, an aromatic solvent such as toluene and acetic acid esters such as butyl acetate (solubility of 1 g / 100 ml or more) propyl acetate. , Ethyl acetate) and hydrocarbon solvents containing alkanes can also be used as long as they can be mixed with the organic solvent A in the aqueous ink.
Of these, toluene, butyl acetate, and methylcyclohexane are preferable.

In addition, two or more kinds of other organic solvents (B) may be used together if necessary.
(Colorant)
The water-based liquid printing ink of the present invention contains a colorant. Examples of the colorant include dyes, inorganic pigments, and organic pigments used in general inks, paints, recording agents, and the like. Of these, pigments such as inorganic pigments and organic pigments are preferable.
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, either an acid-treated pigment or an acid-treated pigment can be used. Specific examples of preferable organic pigments are given below.

Examples of the black pigment 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 the green pigment 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 the purple pigment 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 the brown pigment 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 the inorganic pigment 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 to use chrome yellow or non-leafing is appropriately selected from the viewpoint of brightness and density.

The average particle size of the pigment is preferably in the range of 10 to 200 nm, more preferably about 50 to 150 nm.
The pigment is in an amount sufficient to secure the concentration and coloring power of the liquid printing ink, that is, 1 to 60% by weight based on the total weight of the ink composition, and 10 to 90% by weight of the solid content in the ink composition. It is preferably contained in a proportion of% by weight. In addition, these pigments can be used alone or in combination of two or more.

(Binder resin)
The water-based liquid printing ink of the present invention contains a binder resin. The binder resin is not particularly limited, and urethane resin, polyvinyl alcohols, polyvinylpyrrolidones, polyacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, which are used in general aqueous liquid printing inks, Acrylic copolymers such as vinyl acetate-acrylic acid ester copolymers, acrylic acid-alkyl ester copolymers; styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylic acid Styrene-acrylic acid resins such as alkyl ester copolymers, styrene-α-methylstyrene-acrylic acid copolymers, styrene-α-methylstyrene-acrylic acid-acrylic acid alkyl ester copolymers; styrene-maleic acid; styrene -Maleic anhydride; Vinylnaphthalene-acrylic acid copolymer; Vinylnaphthalene-maleic acid copolymer; Vinyl acetate-ethylene copolymer, Vinyl acetate-Fatigue vinyl ethylene copolymer, Vinyl acetate-maleic acid ester copolymer , Vinyl acetate-crotonic acid copolymer, vinyl acetate-acrylic acid copolymer and other vinyl acetate-based copolymers and salts thereof can be used. These can also be used in combination as appropriate depending on the desired physical characteristics.

Among them, it is preferable to use an acrylic resin or a urethane resin as the binder resin because it is easily available.

(acrylic resin)
The acrylic resin is not particularly limited, and examples thereof include homopolymerization or copolymerization of (meth) acrylate and copolymers obtained by copolymerizing a vinyl monomer copolymerizable with (meth) acrylate. Further, it is preferable that the copolymer has an acid value for the purpose of imparting water dispersibility and water solubility.
In the present invention, "(meth) acrylate" refers to either or both of acrylate and methacrylate, and "(meth) acrylic" refers to either or both of acrylic and methacrylic acid.

Examples of vinyl monomers that can be copolymerized with (meth) acrylates and (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, and t. -Alkyl (meth) acrylates such as butyl (meth) acrylates, isopropyl (meth) acrylates and isobutyl (meth) acrylates; aromatic (meth) acrylates such as benzyl (meth) acrylates; 2-hydrodoxyethyl (meth) acrylates. , 2-hydroxypropyl (meth) acrylate and other hydroxyl group-containing monomers; methoxypolyethylene glycol mono (meth) acrylate, methoxypolypropylene glycol mono (meth) acrylate and other alkyl polyalkylene glycol mono (meth) acrylate; perfluoroalkyl ethyl (meth) acrylate ) Fluorine-based (meth) acrylates such as acrylates; styrene, styrene derivatives (p-dimethylsilylstyrene, (p-vinylphenyl) methylsulfide, p-hexynylstyrene, p-methoxystyrene, p-tert-butyldimethylsiloxystyrene) , O-Methylstyrene, p-methylstyrene, p-tert-butylstyrene, α-methylstyrene, etc.), vinylnaphthalene, vinylanthracene, aromatic vinyl compounds such as 1,1-diphenylethylene; glycidyl (meth) acrylate, Epoxy (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, trimethylpropantri (meth) acrylate, tetramethylene glycol tetra (meth) acrylate, 2-hydroxy-1,3-diacryloxy Propane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl (meth) acrylatetricyclodecanyl (meth) (Meta) acrylate compounds such as acrylate, tris (acryloxyethyl) isocyanurate, urethane (meth) acrylate; alkylamino such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate (Meta) acrylate having a group; Vinyl pyridine compound such as 2-vinylpyridine, 4-vinylpyridine, naphthylvinylpyridine; 1 , 3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, conjugated diene such as 1,3-cyclohexadiene, etc. Can be mentioned. These monomers may be used alone or in combination of two or more.

Further, for the purpose of introducing one or more acidic groups selected from the group consisting of a carboxyl group and a carboxylate group in which the carboxyl group is neutralized with a basic compound, (meth) acrylic acid, crotonic acid, and itaconic acid. , Maleic acid, fumaric acid, β- (meth) acryloyloxyethyl hydrogen succinate, β- (meth) acryloyloxyethyl hydrogen phthalate and other (meth) acrylic monomers having a carboxyl group are copolymerized to increase the acid value. A copolymer having can be obtained.
When an acidic group is introduced, it is preferable to appropriately adjust the amount of the monomer so that the acid value is in a desired range, which will be described in detail later.

The copolymer can be produced, for example, by polymerizing various monomers in a temperature range of 50 ° C. to 180 ° C. in the presence of a polymerization initiator, and is more preferably in a temperature range of 80 ° C. to 150 ° C. Examples of the polymerization method include a massive polymerization method, a solution polymerization method, a suspension polymerization method, and an emulsion polymerization method. In addition, examples of the polymerization mode include random copolymers, block copolymers, graft copolymers, and the like.

The copolymer used in the present invention may be a core-shell type. In the present invention, the core-shell type resin refers to a state in which the polymer (a2) is dispersed in an aqueous medium by the polymer (a1), and usually, the polymer (a1) is present on the outermost side of the resin particles to form a shell. In many cases, a portion is formed and a part or all of the polymer (a2) forms a core portion. Hereinafter, in the present invention, the resin forming the shell portion will be referred to as a polymer (a1), and the resin forming the core portion will be referred to as a polymer (a2).

[Polymer constituting the shell portion (a1)]
The core-shell type resin used in the present invention is one or more hydrophilic groups selected from the group consisting of a carboxyl group and a carboxylate group formed by neutralizing the carboxyl group of the polymer (a1) constituting the shell portion. It is preferable that it is composed of one containing an acrylic resin having. At that time, the acid value of the shell portion is preferably in the range of 40 mgKOH / g or more and 250 mgKOH / g or less, and more preferably 120 mgKOH / g or less.

It is preferable that the carboxyl group of the polymer (a1) constituting the shell portion is neutralized with a basic compound to form a carboxylate group.

As the basic compound that can be used for neutralization, for example, ammonia, triethylamine, morpholine, monoethanolamine, diethylethanolamine and the like can be used, and ammonia and triethylamine can be used to withstand the temperature of the coating film. It is preferable for further improving the property, corrosion resistance and chemical resistance.

The amount of the basic compound used is [basic compound / carboxyl group] with respect to the total amount of the carboxyl groups of the polymer (a1) in order to further improve the water dispersion stability of the obtained core-shell type resin. It is preferable to use in the range of = 0.2 to 2 (molar ratio).

Among the monomers having a polymerizable unsaturated double bond, it is preferable to use a monomer obtained by polymerizing a (meth) acrylic monomer containing a (meth) acrylic monomer having a carboxyl group. In particular, as the polymer (a1), methyl (meth) acrylate, butyl (meth) acrylate, in order to adjust the glass transition temperature (Tg1) of the polymer (a1) in the range of 20 ° C. to 100 ° C. It is more preferable to use a polymer obtained by combining and polymerizing (meth) acrylic acid or the like in order to form a coating film having excellent film-forming property and excellent temperature water resistance, corrosion resistance and chemical resistance.

[Polymer constituting the core portion (a2)]
As the polymer (a2) constituting the core portion, a copolymer such as an acrylic monomer similar to the above-mentioned acrylic resin can be used.
At this time, the weight average molecular weight of the core portion is preferably in the range of 200,000 to 3,000,000, and more preferably 800,000 or more. Tg is preferably in the range of −30 ° C. to 30 ° C.

As the polymer (a2) constituting the core portion, a copolymer such as an acrylic monomer similar to the above-mentioned acrylic resin can be used, but among them, it is preferably produced in an aqueous medium. Specifically, it can be produced by collectively supplying or sequentially supplying the monomer and the polymerization initiator or the like to a reaction vessel containing an aqueous medium for polymerization. At that time, a pre-emulsion is produced by mixing the monomer, an aqueous medium, and a reactive surfactant or the like in advance, and the polymerization initiator or the like is supplied to a reaction vessel containing the aqueous medium. It may be polymerized.

Examples of the polymerization initiator that can be used in producing the polymer (a2) include radical polymerization initiators such as persulfate, organic peroxide, and hydrogen peroxide, and 4,4'-azobis (4-4'-azobis). Azo initiators such as cyanovaleric acid) and 2,2'-azobis (2-amidinopropane) dihydrochloride can be used. Further, the radical polymerization initiator may be used as a redox polymerization initiator in combination with a reducing agent described later.

As the persulfate, for example, potassium persulfate, sodium persulfate, ammonium persulfate and the like can be used. Examples of the organic peroxide include benzoyl peroxide, lauroyl peroxide, decanoyle peroxide, t-butyl cumyl peroxide, dicumyl peroxide, t-butyl peroxylaurate, and t-butyl peroxybenzoate. , Kumen hydroperoxide, paramentan hydroperoxide, t-butyl hydroperoxide and the like can be used.

Examples of the reducing agent include ascorbic acid and its salt, erythorbic acid and its salt (sodium salt, etc.), tartrate acid and its salt, citric acid and its salt, formaldehyde sulfoxylate metal salt, sodium thiosulfate, and the like. Sodium thiosulfate, ferric chloride, etc. can be used.

The amount of the polymerization initiator used may be an amount that allows the polymerization to proceed smoothly, but it is preferable that the amount used is as small as possible from the viewpoint of maintaining the excellent corrosion resistance of the obtained coating film, and is used for the production of the vinyl polymer (a2). It is preferably 0.01% by mass to 0.5% by mass with respect to the total amount of the monomers used. When the polymerization initiator is used in combination with the reducing agent, the total amount of the polymerization initiator used is preferably within the above range.

In addition, when producing the pre-emulsion, a reactive surfactant, anionic surfactant, nonionic surfactant, cationic surfactant, amphoteric surfactant and the like are used. May be good.

The acid value of the copolymer is preferably 20 mgKOH / g or more, 120 mgKOH / g or less, and more preferably 25 mgKOH or more. When the acid value is 20 mgKOH / g or more, the friction resistance, water friction resistance, and scratch resistance of the laminate can be improved when the curing agent is added.

The acid value referred to here indicates the number of milligrams of potassium hydroxide required to neutralize the acidic component contained in 1 g of the resin.

The weight average molecular weight of the copolymer is preferably in the range of 5,000 to 100,000. When the weight average molecular weight is 5,000 or more, the friction resistance and the water friction resistance of the laminate tend to be maintained without lowering the heat resistance of the resin film. If it is 100,000 or less, the laminate tends to have both substrate adhesion and scratch resistance.

The glass transition temperature (Tg) of the copolymer is preferably in the range of 0 ° C. to 55 ° C. When the Tg of the copolymer is 0 ° C. or higher, the film strength is maintained and the water friction resistance of the laminate is not lowered, and when the Tg is 55 ° C. or lower, the compatibility with other printing layers is lowered. However, the abrasion resistance, water friction resistance, and scratch resistance of the laminate tend to be kept good.

The glass transition temperature (Tg1) refers to a so-called calculated glass transition temperature, and refers to a value calculated by the following method.
(Equation 1) 1 / Tg (K) = (W1 / T1) + (W2 / T2) + ... (Wn / Tn)
(Equation 2) Tg (° C.) = Tg (K) -273
W1, W2, ... Wn in the formula 1 represent the mass% of each monomer with respect to the total mass of the monomers used for producing the polymer, and T1, T2, ... Tn are the homopolymers of each monomer. Represents the glass transition temperature (K). As the values of T1, T2, ... Tn, the values described in Polymer Handbook (Fourth Edition, J. Brandrup, E.H. Immunogut, EA Grulke) are used.
Although the glass transition temperature of the homopolymer of each monomer is not described in the Polymer Hand Book, the glass transition temperature is based on JIS K7121 using a differential scanning calorimeter "DSC Q-100" (manufactured by TA Instrument). It was measured by the method described above. Specifically, the polymer from which the solvent has been completely removed by vacuum suction is measured for a change in calorific value in the range of -100 ° C to + 200 ° C at a temperature rise rate of 20 ° C./min, and an extended straight line of each baseline. The point where the straight line at the same distance in the vertical axis direction and the curve of the stepwise change portion of the glass transition intersect was defined as the glass transition temperature.

(Urethane resin)
The urethane resin has, for example, a polyol such as a polyether polyol, a polyester polyol, or a polycarbonate polyol, and a hydrophilic group such as an anionic group, a cationic group, a polyoxyethylene group, or a polyoxyethylene-polyoxypropylene group. Examples thereof include a urethane resin obtained by reacting a polyol with a polyisocyanate. The weight average molecular weight of the urethane resin is not particularly limited, but is generally 5000 to 20000, and more preferably 20000 to 150,000.

Examples of the polyether polyol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol. Glycerin, Trimethylol ethane, Trimethylol propane, Sorbitol, Sucrose, Aconit sugar, Femimeric acid, Phosphoric acid, Ethylene diamine, Diethylene triamine, Triisopropanolamine, Pyrogalol, Dihydroxybenzoic acid, Hydroxyphthalic acid, 1,2,3-Propane A compound having two or more active hydrogen groups such as trithiol and an addition polymerization of a cyclic ether compound such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, or cyclophenylene, or the cyclic ether compound. Can be mentioned by ring-opening polymerization using a cation catalyst, a protonic acid, a Lewis acid, or the like as a catalyst.

The polyester polyol is obtained by a dehydration condensation reaction of a diol compound, a dicarboxylic acid, a hydroxycarboxylic acid compound or the like, a ring-opening polymerization reaction of a cyclic ester compound such as ε-caprolactone, and a copolymerization of the polyester obtained by these reactions. Be done. Examples of the diol compound used as a raw material for this polyester polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 3-methyl-1,5-pentane. Diol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexanediol, 1 , 4-Cyclohexanedimethanol, bisphenol A, hydrogenated bisphenol A, hydroquinone, and alkylene oxide adducts thereof and the like.

Examples of the dicarboxylic acid used as a raw material for the polyester polyol include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid, 1,3-cyclopentanedicarboxylic acid, and 1,4. -Cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis (Phenoxy) ethane-p, p'-dicarboxylic acid and the like can be mentioned.

Examples of the hydroxycarboxylic acid used as a raw material for the polyester polyol include p-hydroxybenzoic acid and p- (2-hydroxyethoxy) benzoic acid.

As the polycarbonate polyol, for example, one obtained by reacting a carbonic acid ester with a low molecular weight polyol, preferably a linear aliphatic diol, can be used.

As the carbonic acid ester, methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclocarbonate, diphenyl carbonate and the like can be used.

Examples of the low molecular weight polyol capable of reacting with the carbonic acid ester include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, 1,4-butanediol, and 1 , 3-Butandiol, 1,2-Butanediol, 2,3-Butanediol, 1,5-Pentanediol, 1,5-Hexylenediol, 2,5-hexanediol, 1,6-Hexanediol, 1, 7-Heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,4-cyclohexanediol, 1,4 -Relatively low molecular weight dihydroxy compounds such as -cyclohexanedimethanol, hydroquinone, resorcin, bisphenol-A, bisphenol-F, 4,4'-biphenol, and polyether polyols such as polyethylene glycol, polypropylene glycol and polyoxytetramethylene glycol. Alternatively, polyester polyols such as polyhexamethylene adipate, polyhexamethylene succinate, and polycaprolactone can be used.

The polycarbonate structure is preferably used in the range of 10% by mass to 90% by mass with respect to the total mass of the polyol used for producing the polycarbonate-based urethane resin and the polyisocyanate.

In addition, the urethane resin has a hydrophilic group in order to impart dispersion stability in the water-based liquid printing ink. As the hydrophilic group, an anionic group, a cationic group, or a nonionic group can be generally used, but it is preferable to use an anionic group or a cationic group.

As the anionic group, for example, a carboxyl group, a carboxylate group, a sulfonic acid group, a sulfonate group and the like can be used, and among them, a carboxylate group partially or wholly neutralized with a basic compound or the like can be used. It is preferable to use a sulfonate group in order to maintain good water dispersibility.

Examples of the basic compound that can be used for neutralizing the carboxyl group and the sulfonic acid group as the anionic group include organic amines such as ammonia, triethylamine, pyridine and morpholine, alkanolamines such as monoethanolamine, and Na. Examples thereof include metal base compounds containing K, Li, Ca and the like.

Further, as the cationic group, for example, a tertiary amino group or the like can be used. As the acid that can be used to neutralize a part or all of the tertiary amino group, formic acid, acetic acid and the like can be used, for example. Further, as the quaternizing agent that can be used when partially or all of the tertiary amino group is quaternized, for example, dialkyl sulfates such as dimethyl sulfate and diethyl sulfate can be used.

The nonionic group includes, for example, a polyoxyalkylene group such as a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, a poly (oxyethylene-oxypropylene) group, and a polyoxyethylene-polyoxypropylene group. Can be used. Among them, it is preferable to use a polyoxyalkylene group having an oxyethylene unit in order to further improve the hydrophilicity.

The presence of 0.5% by mass to 30% by mass of the hydrophilic group with respect to the entire urethane resin imparts even better water dispersibility, and may be in the range of 1% by mass to 20% by mass. More preferred.

Further, a cross-linking agent described later can be used depending on the desired physical properties. When the cross-linking agent is used, it is preferable to use the urethane resin having a functional group capable of cross-linking with the functional group of the cross-linking agent.

Examples of the functional group include a carboxyl group and a carboxylate group that can be used as the hydrophilic group. The carboxyl groups and the like contribute to the water dispersion stability of the urethane resin in an aqueous medium, and when they undergo a cross-linking reaction, they also act as the functional groups and can partially carry out a cross-linking reaction of the cross-linking agent.

When a carboxyl group or the like is used as the functional group, the urethane resin preferably has an acid value of 2 to 55, and it is preferable to use a urethane resin having an acid value of 15 to 50. It is preferable to improve the above. The acid value referred to in the present invention is a theoretical value calculated based on the amount of the acid group-containing compound such as the carboxyl group-containing polyol used in the production of the urethane resin.

The urethane resin can be produced, for example, by reacting a polyol, a polyisocyanate, and a chain extender, if necessary.

As the chain extender, polyamines, other active hydrogen atom-containing compounds and the like can be used.

Examples of the polyamine include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4'-dicyclohexylmethanediamine, and 3,3'-. Diamines such as dimethyl-4,4'-dicyclohexamethylenediamine, 1,4-cyclohexanediamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, N-ethylaminoethylamine, N-Methylaminopropylamine; diethylenetriamine, dipropylenetriamine, triethylenetetramine; hydrazine, N, N'-dimethylhydrazine, 1,6-hexamethylenebishydrazine; dihydrazide succinate, dihydrazide adipate, dihydrazide glutarate, sebacic acid Dihydrazide, isophthalic acid dihydrazide; β-semicarbazide propionate hydrazide, 3-semicarbazid-propyl-carbazic acid ester, semicarbazid-3-semicarbazidemethyl-3,5,5-trimethylcyclohexane can be used and ethylenediamine. It is preferable to use.

Examples of the other active hydrogen-containing compound include ethylene glycol, diethylene recall, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, and neo. Glycols such as pentyl glycol, saccharose, methylene glycol, glycerin, sorbitol; bisphenol A, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenylsulfone, hydrogenated bisphenol A, hydroquinone Glycols such as, water, etc. can be used.

In the chain extender, for example, the equivalent of the amino group and the active hydrogen atom-containing group of the chain extender is the equivalent of the isocyanate group of the urethane prepolymer obtained by reacting the polyol with polyisocyanate. It is preferably used in the range of 1.9 or less (equivalent ratio), more preferably in the range of 0.0 to 1.0 (equivalent ratio), and more preferably 0.5% by mass.

The chain extender can be used during or after the reaction of the polyol with polyisocyanate. Further, the chain extender can also be used when the urethane resin obtained above is dispersed in an aqueous medium to make it aqueous.

Examples of polyols other than the above include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, and 1, , 6-Hexenediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol , Bisphenol A, hydrogenated bisphenol A, hydroquinone and their alkylene oxide adducts, glycerin, trimethylolethane, trimethylolpropane, sorbitol, pentaerythritol and other relatively low molecular weight polyols. These polyols can be used alone or in combination of two or more.

Examples of the polyisocyanate that reacts with the polyol to form a urethane resin include aromatic diisocyanates such as phenylenediocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and naphthalene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, and dicyclohexylmethane. Aliphatic or aliphatic cyclic structure-containing diisocyanates such as diisocyanate, xylylene diisocyanate, and tetramethylxylylene diisocyanate can be used alone or in combination of two or more.

The binder resin is preferably 5 to 50% by mass in terms of solid content of the water-based liquid printing ink of the present invention. When it is 5% by mass or more, the strength of the ink coating film does not decrease, and good substrate adhesion, water friction resistance, and the like are maintained. On the contrary, when it is 50% by mass or less, the decrease in coloring power can be suppressed, the high viscosity can be avoided, and the workability does not decrease. Of these, 5 to 40% by mass is still more preferable, and 5 to 20% by mass is most preferable.

(Surfactant)
In the present invention, a surfactant can be added depending on the desired physical properties. As the surfactant, a general-purpose surfactant can be used in the present technical field without particular limitation, and among them, an acetylene-based surfactant and an alcohol alkoxylate-based surfactant are preferable.

Specifically, as the acetylene-based surfactant used in the present invention, 2,5-dimethyl-3-hexyne-2,5-diol, 3,6-dimethyl-4-octyne-3,6-diol, 2, 4,7,9-Tetramethyl-5-decyne-4,7-diol, 3,5-dimethyl-1-hexyne-3-ol, 3-methyl-1-butyne-3-ol, 3-methyl-1 -Pentyne-3-ol, 3-hexyne-2,5-diol, 2-butyne-1,4-diol and the like can be mentioned. Commercially available products include alkylene oxide-non-modified acetylene glycol-based surfactants such as Surfinol 61, 82, and 104 (all manufactured by Air Products & Chemicals).
Surfinol 420, 440, 465, 485, TG, 2502, Dynol 604, 607, Surfinol SE, MD-20, Orfin E1004, E1010, PD-004, EXP4300, PD-501, PD-502, SPC (all) , Nisshin Kagaku Kogyo Co., Ltd.), acetylenol EH, E40, E60, E81, E100, E200 (all manufactured by Kawaken Fine Chemicals Co., Ltd.) and the like are alkylene oxide-modified acetylene glycol-based surfactants and the like. .. Of these, an alkylene oxide-modified acetylene glycol-based surfactant is preferable.

Specifically, as the alcohol alkoxylate-based surfactant used in the present invention,
DYNWET800 (manufactured by Big Chemie Japan) can be mentioned.
These acetylene-based surfactants and alcohol alkoxylate-based surfactants may be used alone or in combination of two or more.

It is preferable that the total amount of these acetylene-based surfactants and / or alcohol alkoxylate-based surfactants added is 0.1 to 1% by mass of the total amount of the ink. These acetylene-based surfactants may be used alone or in combination of two or more, and the total amount of the acetylene-based surfactant and / or the alcohol alkoxylate-based surfactant added is the total amount. When it is 0.1% by mass or more of the total amount of the ink, the coatability with the base material is improved and the adhesion with the base material can be maintained. If the total amount of the acetylene-based surfactant and / or the alcohol alkoxylate-based surfactant added is 1% by mass or less of the total amount of the ink, the wear resistance, the water-based wear resistance, and the scratch resistance may be lowered. No.

Further, if necessary, other acrylic polymer-based surfactants (for example, Polyflow WS-314 Kyoeisha Chemical Co., Ltd.) and modified silicone-based surfactants (for example, Polyflow KL-401 Kyoeisha Chemical Co., Ltd.) are used. You may.
For the above reasons, the total amount of the surfactant used is preferably 0.1 to 1% by mass of the total amount of the ink.

(wax)
In the present invention, wax can be added depending on the desired physical characteristics. The wax is preferably a carbon-based wax, and the carbon wax is liquid paraffin, natural paraffin, synthetic paraffin, microcrystalline wax, polyethylene wax, fluorocarbon wax, ethylene-propylene copolymer wax, tetrafluoroethylene resin wax, Fisher. Examples include tropsch wax. These waxes may be used alone or in combination of two or more, and the total amount of these waxes added is preferably 0.5 to 5% by mass of the total amount of the ink. When the total amount of wax added is 0.5% by mass or more of the total amount of ink, abrasion resistance, water abrasion resistance, and scratch resistance can be maintained. When the total amount of wax added is 5% by mass or less of the total amount of ink, adhesion to the substrate, abrasion resistance, water abrasion resistance, and scratch resistance can be maintained.

(Hardener)
In the present invention, a curing agent can be added according to desired physical properties. The curing agent capable of reacting with the acid used in the present invention is not particularly limited, and a known curing agent capable of reacting with an acid group that can be used in an aqueous medium can be used. For example, an epoxy-based curing agent, a carbodiimide-based curing agent, an oxazoline-based curing agent, and the like can be mentioned.

The epoxy-based curing agent is not particularly limited as long as it is a compound having at least one epoxy group. Examples of the epoxy-based curing agent include epoxy resins such as bisphenol A diglycidyl ether, modified bisphenol A diglycidyl ether, novolak glycidyl ether, glycerin polyglycidyl ether, and polyglycerin polyglycidyl ether.

The carbodiimide-based curing agent is not particularly limited as long as it is a compound having at least one carbodiimide group (-N = C = N-). As the carbodiimide-based curing agent, a polycarbodiimide compound having at least two or more carbodiimide groups is preferable.

The oxazoline-based curing agent is not particularly limited as long as it is a compound having an oxazoline skeleton. Specific examples of the oxazoline-based curing agent include the Epocross series manufactured by Nippon Shokubai Co., Ltd.

Examples of the epoxy compound include bisphenol A diglycidyl ether and its oligomer, hydride bisphenol A diglycidyl ether and its oligomer, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, and p-oxybenzoic acid. Diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipate diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether , 1,4-Butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and polyalkylene glycol diglycidyl ethers, trimeric acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, Examples thereof include diglycidyl propylene urea, glycerol triglycidyl ether, trimethylol ethane triglycidyl ether, trimethylol propane triglycidyl ether, pentaerythritol tetraglycidyl ether, and triglycidyl ether as a glycerol alkylene oxide adduct.

The amount of the curing agent added in the present invention is preferably 0.1 to 10.0% by mass, more preferably 0.5 to 9.0% by mass in terms of solid content of the total amount of ink.
If the amount added is 0.1% by mass or more, the effect as a curing agent can be obtained, while if it is 10.0% by mass or less, the substrate adhesion, abrasion resistance, and water friction resistance tend to be maintained. Become.

In addition, in the present invention, extender pigments, pigment dispersants, leveling agents, antifoaming agents, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, flame retardants and the like can also be included. Among them, fatty acid amides such as oleic acid amide, stearic acid amide, and erucic acid amide for imparting abrasion resistance and slipperiness, and silicon-based and non-silicon-based defoamers and pigments for suppressing foaming during printing. Various dispersants and the like that improve the wetting of the hydrate are useful.

(Manufacturing method of water-based liquid printing ink)
In the aqueous liquid printing ink of the present invention, a mixture to which a pigment, an aqueous medium, a dispersant, an antifoaming agent and the like are added is dispersed by a disperser to obtain a pigment dispersion. It is obtained by adding an additive such as a resin, an aqueous medium, and if necessary, a leveling agent to the obtained pigment dispersion, and stirring and mixing the mixture. As the disperser, it is manufactured by using a bead mill, an Eiger mill, a sand mill, a gamma mill, an attritor or the like which are generally used for manufacturing gravure and flexographic printing inks.

When the water-based liquid printing ink of the present invention is used as a flexographic ink, its viscosity may be 7 to 25 seconds at 25 ° C., more preferably 10 to 20 seconds, using Zahn Cup # 4 manufactured by Rigosha. be. The surface tension of the obtained flexographic ink at 25 ° C. is preferably 25 to 50 mN / m, more preferably 33 to 43 mN / m. The lower the surface tension of the ink, the better the wettability of the ink to the substrate such as a film. Tend to be easily connected, which tends to cause stains on the printed surface called dot bridge. On the other hand, if the surface tension exceeds 50 mN / m, the wettability of the ink to a base material such as a film is lowered, which tends to cause repelling.

On the other hand, when the water-based liquid printing ink of the present invention is used as a gravure ink, its viscosity may be 7 to 25 seconds at 25 ° C. using Zahn Cup # 3 manufactured by Rigosha, more preferably 10 to 20. Seconds. The surface tension of the obtained gravure ink at 25 ° C. is preferably 25 to 50 mN / m, more preferably 33 to 43 mN / m, as in flexographic ink. The lower the surface tension of the ink, the better the wettability of the ink to the substrate such as a film. Tend to be easily connected, which tends to cause stains on the printed surface called dot bridge. On the other hand, if the surface tension exceeds 50 mN / m, the wettability of the ink to a base material such as a film is lowered, which tends to cause repelling.

(Printed matter)
A printed matter is obtained by printing the water-based liquid printing ink of the present invention on a substrate and providing a printing layer. Usually, a printing layer is obtained by applying an ink to a base material using a gravure method or a flexographic printing method, drying the ink by drying in an oven, and fixing the ink. The drying temperature is usually about 40 to 60 ° C.

Examples of the base material include polyamide resins such as nylon 6, nylon 66, and nylon 46, polyethylene phthalate (PET), polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, and polybutylene naphthalate. Polyester-based resins, polyhydroxycarboxylic acids such as polylactic acid, biodegradable resins typified by aliphatic polyester-based resins such as poly (ethylene succinate) and poly (butylene succinate), polypropylene (PP), polyethylene and the like. Examples thereof include a film made of a thermoplastic resin such as a polyolefin resin, a polyimide resin, a polyarylate resin or a mixture thereof, and a laminate thereof. Among them, a film made of polyester, polyamide, polyethylene and polypropylene can be preferably used.

These 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.

Further, if the printed surface of the film is subjected to a corona discharge treatment, the adhesion to the base material can be further improved, which is preferable. Further, silica, alumina and the like may be vapor-deposited.

In addition, as the base material, high-quality paper used for printing posters, leaflets, CD jackets, direct mails, brochures, packages of cosmetics and beverages, pharmaceuticals, toys, equipment, etc., coated paper, art paper, imitation paper, thin paper, etc. Paper such as thick paper, various synthetic papers, and the like may be used.

Further, in a laminated body in which a plurality of base materials including a printed matter having the printed layer are laminated, the printed layer may be located on the outermost layer of the laminated body (so-called front printing), or a plurality of base materials. It may be a laminate in which a print layer is located between the two (so-called back printing). The water-based liquid printing ink of the present invention is an ink that can be applied to either configuration.

Hereinafter, the present invention will be described in more detail with reference to Examples. In the examples, "parts" represents "parts by mass" and "%" represents "% by 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 Tosoh Corporation under the following conditions.
Separation column: Uses 4 TSKgelGMHR-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 mass. Sample injection volume: 100 microliters. Detector: Differential refractometer.

The acid value of the acrylic resin indicates the number of milligrams of potassium hydroxide required to neutralize the acidic component contained in 1 g of the resin, and the dried water-soluble resins were prepared according to JIS K2501. It was calculated from potentiometric titration with a potassium hydroxide / ethanol solution.

The glass transition temperature (Tg) refers to a so-called calculated glass transition temperature, and refers to a value calculated by the following method.
(Equation 1) 1 / Tg (K) = (W1 / T1) + (W2 / T2) + ... (Wn / Tn)
(Equation 2) Tg (° C.) = Tg (K) -273
W1, W2, ... Wn in the formula 1 represent the mass% of each monomer with respect to the total mass of the monomers used for producing the polymer, and T1, T2, ... Tn are the homopolymers of each monomer. Represents the glass transition temperature (K). As the values of T1, T2, ... Tn, the values described in Polymer Handbook (Fourth Edition, J. Brandrup, E.H. Immunogut, EA Grulke) are used.
Although the glass transition temperature of the homopolymer of each monomer is not described in the Polymer Hand Book, the glass transition temperature is based on JIS K7121 using a differential scanning calorimeter "DSC Q-100" (manufactured by TA Instrument). It was measured by the method described above. Specifically, the polymer from which the solvent has been completely removed by vacuum suction is measured for a change in calorific value in the range of -100 ° C to + 200 ° C at a temperature rise rate of 20 ° C./min, and an extended straight line of each baseline. The point where the straight line at the same distance in the vertical axis direction and the curve of the stepwise change portion of the glass transition intersect was defined as the glass transition temperature.

[Synthesis Example 1: Preparation of Shell Acrylic Resin (Polymer a1)]
The reaction vessel is equipped with a stirrer, a thermometer, a dropping funnel, and a reflux tube, and 60.0 parts of n-propyl acetate is charged. The temperature was raised to 90 ° C. while stirring in a nitrogen atmosphere. On the other hand, 36.0 parts of methyl methacrylate, 10.0 parts of ethyl methacrylate, 20.0 parts of n-butyl methacrylate, 10.0 parts of isobutyl methacrylate, 10.0 parts of 2-ethylhexyl acrylate, 14.0 parts of acrylic acid, and azobis. 1.0 part of isobutyronitrile was dissolved in 40.0 parts of n-propyl acetate, and the mixture was added dropwise over 4 hours using a dropping funnel. After completion of the dropping, the reaction was carried out for another 6 hours. After completion of the reaction, cooling was performed, and 8.0 parts of 30% aqueous ammonia was added to the obtained acrylic resin solution for neutralization. Further, ion-exchanged water was added and solvent substitution was carried out while heating to obtain an aqueous solution of an acrylic resin having a solid content of 55%. The acid value was 105 mgKOH / g, Tg was 65 ° C., and the weight average molecular weight was 16,000.

[Synthesis Example 2: Preparation of Core-Shell Type Acrylic Emulsion (Ac1)]
A stirrer, a thermometer, a dropping funnel, and a reflux tube are provided in a reaction vessel containing 121.2 parts of the acrylic resin aqueous solution prepared in Synthesis Example 1, and 195.5 parts of ion-exchanged water is added. The temperature was raised to 75 ° C. while stirring in a nitrogen atmosphere. Subsequently, using a dropping funnel, 30.0 parts of methyl methacrylate, 20.0 parts of ethyl methacrylate, 25.0 parts of n-butyl acrylate, 25.0 parts of 2-ethylhexyl acrylate, and 3.3 parts of 30% ammonium persulfate were added for 4 hours. Dropped over. After the dropping was completed, the reaction was further carried out for 6 hours to obtain a core-shell type acrylic emulsion aqueous solution having a solid content of 40%. The acid value was 42 mgKOH / g, Tg was 10 ° C., and the weight average molecular weight was 1,200,000.

[Synthesis Example 3: Preparation of Polyurethane Resin Solution (Pu)]
186.9 parts of PLACCEL 212 (polycaprolactone diol manufactured by Daicel Chemical Industries, Ltd., hydroxyl value 90 mgKOH / g) and 100.0 parts of isophorone diisocyanate (abbreviated as IPDI) were charged. This was heated to 110 ° C. with stirring. After 1 hour, the mixture was cooled to 80 ° C., 20.1 parts of dimethylolpropionic acid (abbreviated as DMPA), 0.3 part of dibutyltin dilaurate and 76.8 parts of ethyl acetate were added, and the reaction was carried out at 80 ° C. for 2 hours. I let you. To this, 18.1 part of Bernock DN-980S (manufactured by DIC, hexamethylene diisocyanate polyisocyanate, NCO content 20%) and 408 parts of methyl ethyl ketone (abbreviated as MEK) were added. The NCO group content at this time was 4.9% in terms of solid content.
This was cooled to 30 ° C. or lower, 15.2 parts of triethylamine was added, and then 1293 parts of ion-exchanged water was added to obtain an oil droplet (O / W) type emulsion in water. Subsequently, 234 parts of a 5% aqueous solution of diethylenetriamine was gradually added, and after the addition was completed, the temperature was raised to 60 ° C. and stirring was continued for 30 minutes.
Then, distillation was carried out under reduced pressure to remove a part of the solvent and water.
This is a translucent liquid that is slightly milky white, and when a small amount is taken in a test tube and tetrahydrofuran (abbreviated as THF) is added, it becomes turbid and cross-linked to be insoluble. The non-volatile content was 39.6%, the viscosity was 160 cps, the pH was 7.7, and the average particle size was 28.5 nm.

[Example 1]
10.0 parts of phthalocyanine blue (LDB30 manufactured by DIC) shown in Table 1, 40.0 parts of core-shell type acrylic emulsion (Ac1), and 30.0 parts of water were mixed by stirring and kneaded with a sand mill, and then water 14. 0 parts, 1.0 part of Surfinol 420 (manufactured by Nisshin Kagaku Kogyo Co., Ltd.), which is an alkylene oxide-modified acetylene glycol-based surfactant, and 5.0 parts of Isobutanol were stirred and mixed to obtain indigo printing. It was confirmed that the ink was 20 seconds with Zahn Cup # 3 (manufactured by Rigosha).

[Examples 2-28]
Indigo printing ink was obtained in the same procedure as in Example 1 using 40.0 parts of a core-shell type acrylic emulsion (Ac1) according to the formulations shown in Tables 1 and 2. It was confirmed that the obtained indigo printing ink was used in Zahn Cup # 3 (manufactured by Rigosha) for 20 seconds.

[Examples 29 to 53]
According to the formulations shown in Tables 3 and 4, 40.0 parts of a polyurethane resin solution (Pu) was used instead of the core-shell type acrylic emulsion (Ac1), and an indigo printing ink was obtained in the same procedure as in Example 1. rice field. It was confirmed that the obtained indigo printing ink was used in Zahn Cup # 3 (manufactured by Rigosha) for 20 seconds.

[Examples 54 to 66]
In accordance with the formulation shown in Table 5, 30.0 parts of titanium oxide (TITANIX JR-708 manufactured by TAYCA Corporation) and 35.0 parts of core-shell type acrylic emulsion (Ac1) were added instead of phthalocyanine blue, and Examples were added. A white printing ink was obtained in the same procedure as in 1. It was confirmed that the obtained white printing ink was used in Zahn Cup # 3 (manufactured by Rigosha) for 20 seconds.

[Examples 67 to 79]
According to the formulation shown in Table 6, 30.0 parts of titanium oxide (TITANIX JR-708 manufactured by TAYCA Corporation) and 35.0 parts of polyurethane resin solution (Pu) were added, and white printing was performed in the same procedure as in Example 1. Obtained ink. It was confirmed that the obtained white printing ink was used in Zahn Cup # 3 (manufactured by Rigosha) for 20 seconds.

[Comparative Examples 1 to 12]
According to the formulation shown in Table 7, 10.0 parts of phthalocyanine blue (LDB30 manufactured by DIC Corporation) was added without using any organic solvent (A), and an indigo printing ink was obtained in the same procedure as in Example 1. It was confirmed that the obtained indigo printing ink was used in Zahn Cup # 3 (manufactured by Rigosha) for 20 seconds.

[Comparative Examples 13 to 24]
According to the formulation shown in Table 8, 30.0 parts of titanium oxide (TITANIX JR-708 manufactured by TAYCA Corporation) was added without using any organic solvent (A), and white printing ink was applied in the same procedure as in Example 1. Obtained. It was confirmed that the obtained white printing ink was used in Zahn Cup # 3 (manufactured by Rigosha) for 20 seconds.

<Making printed matter>
Created using a Helio 70-line / cm compressed solid plate on the treated surface of a biaxially stretched polyethylene terephthalate film (E5100 12 μm manufactured by Toyo Spinning Co., Ltd.) with corona discharge treatment on one side using a small gravure single-color printing machine. A printed matter was obtained by printing with the indigo printing ink or the white printing ink at a printing speed of 50 m / min.

The indigo printing ink, the white printing ink, and the obtained printed matter were used to evaluate the foaming and leveling properties of the ink.

<Bubbling>
The bubbling generated in the ink pan after idling at 50 m / min for 15 minutes was visually evaluated with a small gravure single-color printing machine at the time of producing the printed matter.

(Evaluation criteria)
5: Foam is almost not seen and disappears during observation 4: Foam is 30% or less of the ink surface 3: Foam is 50% or less of the ink surface 2: Foam is 80% or more of the ink surface 1 : Foam covers the entire surface of the ink

<Leveling property>
The quality of the leveling property of the ink on the film printing surface was visually evaluated from the viewpoint of the uniformity of color shading.

(Evaluation criteria)
5: There is no shade of color and the leveling is good. 4: The shade of color is slightly seen but hardly noticeable. 3: The shade of color is seen but there is no problem in use.

2: Light-colored parts are generated in streaks and leveling is inferior 1: Light-colored parts are generated in large numbers in streaks and leveling is very poor.

Tables 1 to 8 show the composition of each printing ink and the evaluation results of the printed matter.

From the above results, the water-based liquid ink of the present invention has excellent leveling property even when a small amount of organic solvent is used, and the ink does not foam during printing, so that printing comparable to solvent-based ink is possible.

The water-based liquid ink of the present invention can be widely used as various gravure and flexographic printed matter for industrial products such as food packaging materials, sanitary products, cosmetics, and electronic parts.

Claims (6)

A water-based liquid printing ink containing a colorant, a binder resin, and an water-based medium, which satisfies (1) to (3).
(1) The organic solvent is contained in an amount of 10% by mass or less in the total amount of the water-based liquid printing ink.
(2) The aqueous medium contains water and an organic solvent (A) having a solubility in water (100 ml, 25 ° C.) of 1 to 30 (g / 100 ml).
(3) The ratio of the organic solvent (A) to the other organic solvent (B) is 10:90 to 100: 0. The water-based liquid printing ink according to claim 1, wherein the organic solvent (A) is 1-butanol or isobutanol. The water-based liquid printing ink according to claim 1 or 2, which contains an acrylic resin or a urethane resin as the binder resin. The water-based liquid printing ink according to any one of claims 1 to 3, which is applied to flexographic printing or gravure printing. A printed matter obtained by printing the water-based liquid printing ink according to any one of claims 1 to 4 on a substrate. A laminate having one or a plurality of printing layers on a plastic film, wherein at least one of the printing layers is a printing layer of the water-based liquid printing ink according to any one of claims 1 to 4. Laminated body.