Gravure ink compositions, gravure inks, and laminated structures

Abstract

To provide a gravure ink composition that exhibits good printability, ink stability, and low-temperature stability when used as a gravure ink, and in which the printed layer formed from the gravure ink exhibits good blocking resistance, cutability, and substrate adhesion; a gravure ink containing the gravure ink composition; and a laminate having a printed layer formed from the gravure ink. [Solution] A gravure ink composition comprising a polyurethane resin (P) and an organic solvent (S), wherein the polyurethane resin (P) has units based on a polyol (A) and units based on an organic diisocyanate (B), and the polyol (A) contains two or more types of linear polyether polyols (A1).

Description

Technical Field

[0001] The present invention relates to a composition for gravure ink, gravure ink, and a laminate.

Background Art

[0002] Conventionally, various packaging materials have been used to store liquids, powders, or solid foods, detergents, sundries, etc. As such a packaging material, a packaging bag formed by bagging a laminate having a plastic film as a main body and a printed layer formed using printing ink is known. The packaging bag is required to have strength from the aspect of protecting the contents. In addition, the packaging bag is required to have excellent easy-opening property (package cutting property, hereinafter also referred to as "cutting property") during use.

[0003] Patent Document 1 describes that the package cutting property is improved by using a white ink containing a specific resin component.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, although Patent Document 1 describes the physical properties of the resin component, the specific composition and property values are not described, and the configuration of the invention in which good cutting property is exhibited is not clear. In addition, the cutting property is not satisfactory. In addition, the low-temperature stability, which is an important performance required in practical use as an ink product, is not necessarily satisfactory. The present invention has been made in view of the above circumstances, and aims to provide a gravure ink composition that, when used as a gravure ink, exhibits good printability, ink stability, and low-temperature stability, and in which the printed layer formed from the gravure ink exhibits good blocking resistance, cutability, and substrate adhesion; a gravure ink containing the gravure ink composition; and a laminate having a printed layer formed from the gravure ink. [Means for solving the problem]

[0006] The inventors of this invention have diligently conducted research to solve the above-mentioned problems and have arrived at the present invention. In other words, the present invention relates to a gravure ink composition containing a polyurethane resin (P) and an organic solvent (S), wherein the polyurethane resin (P) has units based on a polyol (A) and units based on an organic diisocyanate (B), and the polyol (A) contains two or more linear polyether polyols (A1). Furthermore, the present invention relates to a gravure ink comprising the gravure ink composition of the present invention and an isocyanate-based curing agent (E), and a laminate having a printed layer formed from the gravure ink of the present invention. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a gravure ink composition that, when used as a gravure ink, exhibits good printability, ink stability, and low-temperature stability, and in which the printed layer formed from the gravure ink exhibits good blocking resistance, cutability, and substrate adhesion; a gravure ink containing the gravure ink composition; and a laminate having a printed layer formed from the gravure ink. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view showing an example of a laminated structure of the present invention. [Modes for carrying out the invention]

[0009] Embodiments of the gravure ink composition, gravure ink, and laminate of the present invention will be described. This embodiment is provided to give a better understanding of the spirit of the invention and does not limit the present invention unless otherwise specified.

[0010] <Composition for gravure inks> The gravure ink composition of the present invention contains a polyurethane resin (P) and an organic solvent (S), wherein the polyurethane resin (P) has units based on a polyol (A) and units based on an organic diisocyanate (B), and the polyol (A) contains two or more linear polyether polyols (A1).

[0011] "Polyurethane resin (P)" Polyurethane resin (P) is a resin obtained by reacting an organic diisocyanate (B) and a polyol (A) by known methods such as solution polymerization, and then using a hydroxyl group-containing polyamine as a chain extender (F1), and optionally a chain extender other than a hydroxyl group-containing polyamine (F2) and a reaction stopper (G) on the resulting urethane prepolymer.

[0012] Polyurethane resin (P) has units based on polyol (A) and units based on organic diisocyanate (B) as essential constituent units.

[0013] In the gravure ink composition of the present invention, the polyol (A) contains two or more linear polyether polyols (A1). The linear polyether polyol (A1) is a polyol with a number average molecular weight (Mn) of 500 or more. Examples of polyols with a number-average molecular weight of 500 or more include, in addition to the linear polyether polyol (A1) described above, other polyether polyols (hereinafter also referred to as "other polyether polyols" in this specification), polyester polyols (A2), polylactone polyols (A3), and the like. Polyol (A) may further contain one or more of the following polyols: polyols (A) with a number average molecular weight of 500 or more, and at least two linear polyether polyols (A1), as long as they contain at least two of these linear polyether polyols (A1).

[0014] Examples of linear polyether polyols (A1) include linear adducts of alkylene oxides with 2 to 12 carbon atoms [hereinafter abbreviated as "AO"] to linear diols with less than 500 Mn, which are linear in shape (without having either a branched or cyclic structure).

[0015] Examples of linear diols with a manganese content of less than 500 include aliphatic dihydric alcohols having 2 to 8 carbon atoms [diols that are linear and have hydroxyl groups only at the ends of the linear structure (ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol, etc.)]. Linear diols with a manganese content of less than 500 may be used individually or in combination of two or more.

[0016] As carbon-2 to carbon-12 AOs used as raw materials for linear polyether polyol (A1), ethylene oxide, 1,3-propylene oxide (trimethylene oxide), tetrahydrofuran, α-olefin oxide, etc., can be used. One type of carbon-2 to carbon-12 AO used as a raw material for linear polyether polyol (A1) may be used alone, or two or more types may be block copolymerized or random copolymerized.

[0017] Specific examples of the linear polyether polyol (A1) include polyethylene glycol, polytrimethylene ether glycol, polyoxyethylene / trimethylene ether glycol, polytetramethylene ether glycol, and the like. The linear polyether polyol (A1) may be used alone or in combination of two or more kinds.

[0018] Other polyether polyols include adducts of AO having 2 to 12 carbon atoms to diols with Mn less than 500, which are other than the above-described linear polyether polyol (A1), and the like. Other polyether polyols have at least one of a branched structure and a cyclic structure.

[0019] Examples of the diol with Mn less than 500 include aliphatic dihydric alcohols having 2 to 8 carbon atoms [linear diols having a hydroxyl group only at the end of the linear structure (ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, etc.), linear diols having a hydroxyl group other than at the end of the linear structure (1,2-propanediol, 2,3-propanediol), and diols having a branched alkyl chain (neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, etc.)]; alicyclic group-containing dihydric alcohols having 6 to 10 carbon atoms [1,4-bis(hydroxymethyl)cyclohexane, 2,2-bis(4-hydroxycyclohexyl)propane, etc.]; aromatic ring-containing dihydric alcohols having 8 to 20 carbon atoms [m- or p-xylylene glycol, bis(hydroxyethyl)benzene, bis(hydroxyethoxy)benzene]; AO adducts of bisphenols (bisphenol A, bisphenol S, bisphenol F, etc.), AO adducts of dihydroxynaphthalene, and bis(2-hydroxyethyl) terephthalate, and the like. The diol with Mn less than 500 may be used alone or in combination of two or more kinds.

[0020] Other carbon-2 to carbon-12 AOs used as raw materials for polyether polyols include ethylene oxide, 1,2- or 1,3-propylene oxide, 1,2-, 1,3- or 2,3-butylene oxide, tetrahydrofuran, 3-methyltetrahydrofuran, styrene oxide, α-olefin oxide, and epichlorohydrin. The carbon-2 to carbon-12 AOs used as raw materials for other polyether polyols may be used individually, or two or more may be used in block copolymerization or random copolymerization.

[0021] Among other polyether polyols, those having branched alkyl chains are preferred from the viewpoint of substrate adhesion and low-temperature stability. Specifically, those using a diol with branched alkyl chains as a raw material, where Mn is less than 500, or those using polypropylene glycol (1,2-propylene oxide), 1,2-,2,3- or 1,3-butylene oxide and 3-methyltetrahydrofuran as the AO having 2 to 12 carbon atoms. An example of other polyether polyols having branched alkyl chains is polypropylene glycol. Other polyether polyols may be used individually or in combination of two or more.

[0022] Among linear polyether polyols (A1), those using biomass-derived raw materials include biomass-derived polytrimethylene ether glycol and polytetramethylene ether glycol. Among the linear polyether polyols (A1) derived from biomass, the preferred choice from the viewpoint of substrate adhesion and low-temperature stability is biomass-derived polytrimethylene ether glycol.

[0023] Examples of polyester polyols (A2) include those obtained by condensation of Mn or a polyol with a chemical formula weight of less than 500 with a polycarboxylic acid or its ester-forming derivative [such as acid anhydrides, lower (1-4 carbon atoms) alkyl esters, and acid halides]. Diols (D) are preferred as the Mn or polyol with a chemical formula weight of less than 500, and dicarboxylic acids (C) are preferred as the polycarboxylic acid. In the gravure ink composition of the present invention, it is preferable that the polyol (A) further contains a polyester polyol (A2) having units based on a polycarboxylic acid and units based on a polyol. Furthermore, it is preferable that the polyester polyol (A2) is a polyester polyol having units based on a dicarboxylic acid (C) and units based on a diol (D).

[0024] Examples of dicarboxylic acids (C) or their ester-forming derivatives include aliphatic dicarboxylic acids having 2 to 15 carbon atoms [oxalic acid, succinic acid, adipic acid (C2), sebacic acid (C1), glutaric acid, azelaic acid, maleic acid, and fumaric acid, etc.], aromatic dicarboxylic acids having 8 to 12 carbon atoms [terephthalic acid and isophthalic acid, etc.], and their ester-forming derivatives [acid anhydrides, lower alkyl esters (dimethyl esters and diethyl esters, etc.), acid halides (acid chlorides, etc.)]. Dicarboxylic acids (C) or their ester-forming derivatives may be used individually or in combination of two or more. In the gravure ink composition of the present invention, the dicarboxylic acid (C) preferably contains sebacic acid (c1), and more preferably contains sebacic acid (c1) and adipic acid (c2).

[0025] The dicarboxylic acid (C) preferably contains sebacic acid (c1) derived from biomass. The dicarboxylic acid (C) may also contain adipic acid (c2) derived from petroleum or biomass. From the viewpoint of good cutability, substrate adhesion, and low-temperature stability, the dicarboxylic acid (C) preferably contains biomass-derived sebacic acid (c1) and petroleum-derived or biomass-derived adipic acid (c2).

[0026] When the dicarboxylic acid (C) contains sebacic acid (c1), the content of units based on sebacic acid (c1) relative to the total amount of units based on dicarboxylic acid (C) is preferably 10% to 100% by mass, and more preferably 30% to 70% by mass. When the content of units based on sebacic acid (c1) relative to the total amount of units based on dicarboxylic acid (C) is within the above range, good cutability, substrate adhesion, and low-temperature stability can be achieved.

[0027] When the dicarboxylic acid (C) contains adipic acid (c2), the content of units based on adipic acid (c2) relative to the total amount of units based on dicarboxylic acid (C) is preferably 10% to 70% by mass, and more preferably 30% to 60% by mass. When the content of units based on adipic acid (c2) relative to the total amount of units based on dicarboxylic acid (C) is within the above range, good cutability, substrate adhesion, and low-temperature stability can be achieved.

[0028] In this specification, "units based on dicarboxylic acid (C)" refers to the dicarboxylic acid (C) itself that has reacted with Mn or a polyol with a chemical formula weight of less than 500, without considering dehydration by condensation between dicarboxylic acid (C) and Mn or a polyol with a chemical formula weight of less than 500 (preferably diol (D)). Similarly, "units based on sebaciic acid (c1)", "units based on adipic acid (c2)", and "units based on diol (D)" described later are also treated without considering dehydration by condensation.

[0029] Examples of diol (D) include those similar to the diols with a manganese content of less than 500 mentioned above. Diol (D) may be used alone or in combination of two or more types. In the gravure ink composition of the present invention, the diol (D) preferably contains 1,3-propanediol (d1), more preferably contains 1,3-propanediol (d1) and neopentyl glycol (d3), and even more preferably contains 1,3-propanediol (d1), 1,4-butanediol (d2), and neopentyl glycol (d3).

[0030] The diol (D) preferably contains biomass-derived 1,3-propanediol (d1). The diol (D) may also contain at least one selected from petroleum-derived or biomass-derived 1,4-butanediol (d2) and biomass-derived neopentyl glycol (d3). From the viewpoint of good cutability, substrate adhesion, and low-temperature stability, it is preferable that the diol (D) contains all of the following: biomass-derived 1,3-propanediol (d1), petroleum-derived or biomass-derived 1,4-butanediol (d2), and biomass-derived neopentyl glycol (d3).

[0031] When the diol (D) contains 1,3-propanediol (d1), the content of units based on 1,3-propanediol (d1) relative to the total amount of units based on diol (D) is preferably 10% to 100% by mass, and more preferably 30% to 70% by mass. When the content of units based on 1,3-propanediol (d1) relative to the total amount of units based on diol (D) is within the above range, good cutability, substrate adhesion, and low-temperature stability can be achieved.

[0032] When the diol (D) contains 1,4-butanediol (d2), the content of units based on 1,4-butanediol (d2) relative to the total amount of units based on diol (D) is preferably 10% to 80% by mass, and more preferably 10% to 30% by mass. When the content of units based on 1,4-butanediol (d2) relative to the total amount of units based on diol (D) is within the above range, good cutability, substrate adhesion, and low-temperature stability can be achieved.

[0033] When the diol (D) contains biomass-derived 1,4-butanediol (d2), the content of units based on biomass-derived 1,4-butanediol (d2) relative to the total amount of units based on diol (D) is preferably 10% to 80% by mass, and more preferably 10% to 60% by mass. When the content of units based on biomass-derived 1,4-butanediol (d2) relative to the total amount of units based on diol (D) is within the above range, it is possible to maintain a biomass concentration above a certain level while ensuring good cutability, substrate adhesion, and low-temperature stability.

[0034] When the diol (D) contains neopentyl glycol (d3), the content of units based on neopentyl glycol (d3) relative to the total amount of units based on diol (D) is preferably 10% to 80% by mass, and more preferably 10% to 50% by mass. When the content of units based on neopentyl glycol (d3) relative to the total amount of units based on diol (D) is within the above range, good cutability, substrate adhesion, and low-temperature stability can be achieved.

[0035] The polyester polyol (A2) is a polyester polyol having units based on a dicarboxylic acid (C) and units based on a diol (D), wherein the dicarboxylic acid (C) contains sebacic acid (c1) and the diol (D) contains 1,3-propanediol (d1), and preferably the content of units based on sebacic acid (c1) relative to the total amount of units based on dicarboxylic acid (C) is 10 to 100% by mass, and the content of units based on 1,3-propanediol (d1) relative to the total amount of units based on diol (D) is 10 to 100% by mass.

[0036] Specific examples of polyester polyols (A2) include polyethylene adipate diol, polypropylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyhexamethylene isophthalate diol, polyneopentyl adipate diol, polyethylene propylene adipate diol, polyethylene butylene adipate diol, polybutylene hexamethylene adipate diol, poly(polyoxytetramethylene) adipate diol, poly(3-methylpentylene adipate) diol, polyethylene azelate diol, polyethylene sebacate diol, polybutylene azelate diol, polypropylene sebacate diol, polybutylene sebacate diol, polyneopentyl sebacate diol, and polyneopentyl terephthalate diol. Furthermore, a polyester polyol (A2) can be made from multiple types of diols (D) and multiple types of dicarboxylic acids (C). Examples of such polyester polyols include those obtained by simultaneously mixing two or more diols (D) selected from the group consisting of 1,3-propanediol (d1), 1,4-butanediol (d2), and neopentyl glycol (d3) with two types of dicarboxylic acids (C), adipic acid (c2) and sebacic acid (c1), and reacting them randomly.

[0037] Among polyester polyols (A2), polyester diols having branched alkyl chains are preferred from the viewpoint of cutability, substrate adhesion, and low-temperature stability, polyneopentyl adipate diols and poly(3-methylpentylene adipate) diols are more preferred, and polyneopentyl adipate diols are particularly preferred. Polyester polyol (A2) may be used alone or in combination of two or more types.

[0038] It is preferable that the polyester polyol (A2) has units based on biomass-derived raw materials. When the polyester polyol (A2) has units based on biomass-derived raw materials, it is preferable that the polyester polyol (A2) has a biomass concentration of 60 to 100% by mass. The biomass concentration refers to the mass ratio of the biomass-derived raw materials constituting the polyester polyol (A2) to the mass of the polyester polyol (A2).

[0039] When using a polyester polyol (A2) having units derived from biomass raw materials (or when using a polyol or polycarboxylic acid derived from biomass), the biomass concentration in the resulting urethane resin and gravure ink composition can be improved, making the gravure ink composition an excellent material from a carbon neutrality standpoint. Conventionally, studies have been conducted to improve the biomass concentration in urethane resin and gravure ink compositions, but the cutability, ink stability, substrate adhesion, and low-temperature stability were not sufficient. The inventors have found that by using multiple biomass-derived monomers (polyols, polycarboxylic acids) in combination, it is possible to obtain a gravure ink composition that has sufficient cutability, ink stability, substrate adhesion, and low-temperature stability while increasing the biomass concentration.

[0040] The polyester polyol (A2) is preferably a polyester polyol containing units based on dicarboxylic acid (C) and units based on diol (D). Furthermore, the polyester polyol (A2) is preferably a polyester polyol (A21) whose essential constituent units are units based on biomass-derived polyol (preferably biomass-derived diol (D)) and / or biomass-derived polycarboxylic acid (preferably biomass-derived dicarboxylic acid (C)).

[0041] Examples of biomass-derived polyols include ethylene glycol, 1,2-propanediol, 1,3-propanediol (d1), 1,3-butanediol, 1,4-butanediol (d2), neopentyl glycol (d3), castor oil polyol, and dimerdiol, all of which are relatively easy to obtain. Among these, 1,3-propanediol (d1), 1,4-butanediol (d2), and neopentyl glycol (d3) are preferred in terms of cutability and ink stability. Biomass-derived polyols may be used individually or in combination of two or more.

[0042] The content of biomass-derived polyol-based units relative to the total amount of polyol-based units contained in polyester polyol (A21) is preferably 10 to 100 mol%, more preferably 50 to 100 mol%, and even more preferably 80 to 100 mol%.

[0043] Examples of biomass-derived polycarboxylic acids include succinic acid, adipic acid (C2), 2,5-franzicarboxylic acid, sebacic acid (C1), and dimer acid. Among these, adipic acid (C2) and sebacic acid (C1) are preferred in terms of cutability and low-temperature stability. One type of biomass-derived polycarboxylic acid may be used alone, or two or more types may be used in combination.

[0044] The content of biomass-derived polycarboxylic acid units relative to the total amount of polycarboxylic acid units contained in polyester polyol (A21) is preferably 10 to 100 mol%, more preferably 20 to 100 mol%, and even more preferably 40 to 100 mol%.

[0045] The content of units based on polyester polyol (A21) relative to the total mass of polyol (A) is preferably 20% to 100% by mass, and more preferably 50% to 100% by mass. When the content of units based on polyester polyol (A21) relative to the total mass of polyol (A) is within the above range, good cutability, ink stability, substrate adhesion, and low-temperature stability can be achieved while ensuring the biomass concentration in the polyurethane resin (P).

[0046] From the viewpoint of solvent solubility, the hydroxyl value of polyester polyol (A2) is preferably 22 to 225 mg KOH / g, and more preferably 28 to 113 mg KOH / g. The hydroxyl value of polyester polyol (A2) is measured in accordance with JIS K0070-1992.

[0047] The acid value of polyester polyol (A2) is preferably 0.0 to 1.0 mg KOH / g, and more preferably 0.0 to 0.6 mg KOH / g, from the viewpoint of blocking resistance and cutability. The acid value of polyester polyol (A2) is measured in accordance with JIS K0070-1992.

[0048] The number-average molecular weight (Mn) of the polyester polyol (A2) is preferably 500 to 5000, and more preferably 1000 to 4000, from the viewpoint of solvent solubility. The number-average molecular weight (Mn) of polyester polyol (A2) as used herein is the value measured by gel permeation chromatography (GPC) under the following conditions.

[0049] (Measurement conditions) Equipment: "Waters Alliance 2695" [manufactured by Waters] Column: A combination of one each of "TSKgel® Guardcolumn Super HL", "TSKgel SuperH2000", "TSKgel SuperH3000", and "TSKgel SuperH4000" (all manufactured by Tosoh Corporation) (total of 4 columns) linked together. Sample solution: 0.25% by mass tetrahydrofuran solution Solution injection volume: 10μL Flow rate: 0.6mL / min Measurement temperature: 40℃ Detection device: Refractive index detector Reference substance: Standard polyethylene glycol

[0050] Examples of polylactone polyols (A3) include those obtained by ring-opening polymerization of lactone monomers (γ-butyrolactone, γ-valerolactone, ε-caprolactone, and mixtures of two or more thereof) using a diol with a manganese content of less than 500 as an initiator. Specific examples of polylactone polyols (A3) include polybutyrolactone diol, polyvalerolactone diol, and polycaprolactone diol. Polylactone polyol (A3) may be used alone or in combination of two or more types.

[0051] The content of units based on polyol (A) relative to the total mass of polyurethane resin (P) is preferably 40% to 85% by mass, and more preferably 50% to 80% by mass. When the content of units based on polyol (A) relative to the total mass of polyurethane resin (P) is within the above range, good cutability, ink stability, and substrate adhesion can be achieved.

[0052] Examples of organic diisocyanates (B) in the present invention include aliphatic diisocyanates (B1) having 4 to 22 carbon atoms, alicyclic diisocyanates (B2) having 8 to 18 carbon atoms, aromatic diisocyanates (B3) having 8 to 26 carbon atoms, and aromatic aliphatic diisocyanates (B4) having 10 to 18 carbon atoms.

[0053] Examples of aliphatic diisocyanates (B1) having 4 to 22 carbon atoms include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis(2-isocyanatoethyl) fumarate, and bis(2-isocyanatoethyl) carbonate.

[0054] Examples of alicyclic diisocyanates (B2) having 8 to 18 carbon atoms include isophorone diisocyanate (hereinafter abbreviated as "IPDI"), 4,4-dicyclohexylmethane diisocyanate, cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis(2-isocyanatoethyl)-4-cyclohexene-1,2-dicarboxylate, and 2,5- or 2,6-norbornane diisocyanate.

[0055] Examples of aromatic diisocyanates (B3) having 8 to 26 carbon atoms include 1,3- or 1,4-phenylenediisocyanate, 2,4- or 2,6-tolylenediisocyanate, 4,4'- or 2,4'-diphenylmethanediisocyanate, polyaryldiisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5-naphthylenediisocyanate, and m- or p-isocyanatophenylsulfonyl isocyanates.

[0056] Examples of aromatic aliphatic diisocyanates (B4) having 10 to 18 carbon atoms include m- or p-xylylene diisocyanate and α,α,α',α'-tetramethylxylylene diisocyanate.

[0057] Among these, alicyclic diisocyanates (B2) having 8 to 18 carbon atoms are preferred from the viewpoint of substrate adhesion and low-temperature stability, and IPDI is preferred from the viewpoint of solvent solubility and adhesion of polyurethane resin (P). Organic diisocyanate (B) may be used alone or in combination of two or more types.

[0058] The content of units based on organic diisocyanate (B) relative to the total mass of polyurethane resin (P) is preferably 10% to 40% by mass, and more preferably 20% to 35% by mass. When the content of units based on organic diisocyanate (B) relative to the total mass of polyurethane resin (P) is within the above range, good cutability and adhesion to the substrate can be achieved.

[0059] In obtaining the polyurethane resin (P) in the gravure ink composition of the present invention, in addition to the polyol (A) (two or more types of polyether polyol (A1)) and organic diisocyanate (B), a hydroxyl group-containing polyamine is used as a chain extender (F1). That is, the polyurethane resin (P) has units based on the hydroxyl group-containing polyamine. Furthermore, in order to adjust the molecular weight of the polyurethane resin (P), a chain extender (F2) other than Mn or a hydroxyl group-containing polyamine with a chemical formula weight of less than 500 (hereinafter also simply referred to as chain extender (F2)) and a reaction stopper (G) can be used.

[0060] The chain extender (F1) is a hydroxyl group-containing polyamine. A polyamine is a compound in which the total number of nitrogen atoms from primary amines and secondary amines in one molecule is two or more. The manganese (Mn) or chemical formula weight of the hydroxyl group-containing polyamine is preferably less than 500. The number of hydroxyl groups in the hydroxyl group-containing polyamine is preferably 1 to 4, and more preferably 1 to 2. The total number of nitrogen atoms from primary amines and secondary amines in the hydroxyl group-containing polyamine is preferably 2 to 4, and more preferably 2 to 3. The chain extender (F1) may be used alone or in combination of two or more types.

[0061] As the chain extender (F1), a linear or branched hydroxyl group-containing diamine having 2 to 10 carbon atoms is preferred. Examples of linear or branched hydroxyl group-containing diamines having 2 to 10 carbon atoms include aminoethylethanolamine, N-(3-hydroxypropyl)ethylenediamine, N-(2-hydroxyethyl)-1,3-propanediamine, and 2-[bis(2-aminoethyl)amino]-ethanol, with aminoethylethanolamine and N-(2-hydroxyethyl)-1,3-propanediamine being preferred.

[0062] Other chain extenders (F2) besides hydroxyl group-containing polyamines with Mn or a chemical formula weight of less than 500 include polyamines (F2-1) and polyols (F2-2) that do not contain hydroxyl groups. The chain extender (F2) may be used alone or in combination of two or more types.

[0063] Examples of polyamines (F2-1) that do not contain hydroxyl groups include diamines with 2 to 12 carbon atoms (ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, toluenediamine, and piperazine, etc.), poly(n=2-6)alkylene(2-6 carbon atoms) poly(n=3-7)amines (diethylenetriamine, dipropylenetriamine, dihexylentriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, and hexaethyleneheptamine, etc.), and hydrazine or its derivatives (dibasic acid dihydrazides, such as adipic acid dihydrazide, etc.). Of these, alicyclic diamines are preferred from the viewpoint of cutability, substrate adhesion, and low-temperature stability, and isophorone diamines are even more preferred.

[0064] Examples of polyols (F2-2) include those similar to those exemplified as diols with Mn less than 500, and 1,3-propanediol and 1,4-butanediol are preferred from the viewpoint of cutability and ink stability. Note that biomass-derived polyols can also be used as polyols (F2-2).

[0065] The total content of units based on chain extenders (F1) and (F2) relative to the total mass of polyurethane resin (P) is preferably 1% to 30% by mass, and more preferably 5% to 15% by mass. When the total content of units based on chain extenders (F1) and (F2) relative to the total mass of polyurethane resin (P) is within the above range, good cutability and adhesion to the substrate can be achieved.

[0066] The content of units based on the chain extender (F1) relative to the total mass of the polyurethane resin (P) is preferably 2.0% to 8.0% by mass, and more preferably 2.5% to 7.0% by mass. When the content of units based on the chain extender (F1) relative to the total mass of the polyurethane resin (P) is within the above range, good cutability and adhesion to the substrate can be achieved.

[0067] When the polyurethane resin (P) has units based on a chain extender (F2), the content of units based on the chain extender (F1) relative to the total content of units based on chain extenders (F1) and (F2) is preferably 20% to 70% by mass, and more preferably 35% to 65% by mass. When the content of units based on the chain extender (F1) relative to the total content of units based on chain extenders (F1) and (F2) is within the above range, good cutability and adhesion to the substrate can be achieved.

[0068] Examples of reaction stoppers (G) include monoalcohols having 1 to 10 carbon atoms (methanol, propanol, butanol, and 2-ethylhexanol, etc.) and monoamines having 2 to 8 carbon atoms [mono or dialkylamines having 2 to 8 carbon atoms (n-butylamine and dibutylamine, etc.), mono or dialkanolamines having 2 to 6 carbon atoms (monoethanolamine, diethanolamine, and propanolamine, etc.)]. Of these, mono or dialkanolamines having 2 to 6 carbon atoms are preferred. Reaction stoppers (G) may be used alone or in combination of two or more.

[0069] The mass ratio [(A):(B):(F)] of polyol (A), organic diisocyanate (B), and chain extender (F) in the polyurethane resin (P) is preferably 100:(25~70):(5~35), and more preferably 100:(35~60):(8~25), from the viewpoint of the cutability, substrate adhesion, and low-temperature stability of the polyurethane resin (P). The chain extender (F) refers to both (total) of the above-mentioned chain extenders (F1) and (F2).

[0070] The mass ratio [(A):(B):(F1)] of polyol (A), organic diisocyanate (B), and chain extender (F1) in the polyurethane resin (P) is preferably 100:(30~65):(3~15), and more preferably 100:(35~60):(4~12), from the viewpoint of the cutability, substrate adhesion, and low-temperature stability of the polyurethane resin (P).

[0071] The method for producing the polyurethane resin (P) is not particularly limited and may be a one-shot method in which a polyol (A), an organic diisocyanate (B), a chain extender (F1), and optionally a chain extender (F2) and a reaction stopper (G) are reacted at once, or a multi-stage method in which the reactions are carried out in steps [for example, a method in which (A), (B) and optionally (F1) and (F2) are reacted to form an isocyanate group-terminated prepolymer, and then (F1), (F2) and optionally (G) are added and reacted further]. From the viewpoint of substrate adhesion, it is preferable to first form an isocyanate-terminated prepolymer in the multi-stage method described above, and then introduce amino groups to the ends of the polyurethane urea molecular chains by using a hydroxyl-containing polyamine as a chain extender (F1) and a C2-C12 diamine as a chain extender (F2-1) such that the total amount of amino groups in these amines is in excess of the equivalent amount of isocyanate groups in the isocyanate-terminated prepolymer.

[0072] In the production of polyurethane resin (P), the molar ratio (isocyanate group:active hydrogen-containing group) of the isocyanate group of organic diisocyanate (B) and the active hydrogen-containing groups of the polyol (A), the chain extender (F1) which is a hydroxyl group-containing polyamine, the chain extender other than the hydroxyl group-containing polyamine (F2) used as needed, and the reaction stopper (G) is preferably 0.7:1 to 0.99:1, and more preferably 0.95:1 to 0.99:1, from the viewpoint of the cutability, substrate adhesion, and low-temperature stability of the polyurethane resin (P).

[0073] In the present invention, the polyurethane resin (P) preferably has a biomass concentration of 20 to 80% by mass. In this specification, biomass concentration means the mass ratio of biomass-derived raw materials constituting the polyurethane resin (P) to the mass of the polyurethane resin (P).

[0074] The polyurethane resin (P) in the present invention contains at least a hydroxyl group in its side chain. A polyurethane resin (P) containing at least hydroxyl groups in its side chains can be produced by using a chain extension agent (F1), which is a hydroxyl group-containing polyamine, and carrying out a chain extension reaction using only highly reactive amino groups. In the present invention, the polyurethane resin (P) preferably has a hydroxyl value of 1 mg KOH / g to 45 mg KOH / g, more preferably 22 mg KOH / g to 45 mg KOH / g, and even more preferably 26 mg KOH / g to 40 mg KOH / g. When the hydroxyl value of the polyurethane resin (P) is 1 mg KOH / g or more, the coating film (printed layer) formed by the gravure ink containing the gravure ink composition of the present invention exhibits excellent cutability and substrate adhesion. When the hydroxyl value of the polyurethane resin (P) is 45 mg KOH / g or less, the coating film (printed layer) formed by the gravure ink containing the gravure ink composition of the present invention exhibits excellent cutability and ink stability. The hydroxyl value of the polyurethane resin (P) can be adjusted by the amount of chain extender (F1), which is a hydroxyl group-containing polyamine, used. In the gravure ink composition of the present invention, the polyurethane resin (P) preferably has hydroxyl groups in at least its side chains and has a hydroxyl value of 1 to 45 mgKOH / g.

[0075] The hydroxyl value of polyurethane resin (P) is a value measured in accordance with JIS K0070-1992.

[0076] In the present invention, the polyurethane resin (P) preferably has a urethane bond content of 1.1 mmol / g to 2.2 mmol / g, and more preferably 1.2 mmol / g to 1.8 mmol / g. When the urethane bond content of the polyurethane resin (P) is within the above range, the coating film (printed layer) formed by the gravure ink containing the gravure ink composition of the present invention exhibits excellent cutability. The urethane bond content of the polyurethane resin (P) can be adjusted by the molecular weight of the polyol (A), etc.

[0077] The polyurethane resin (P) in the present invention may be a polyurethane urea resin containing urea groups. When the polyurethane resin (P) is a polyurethane urea resin, the urea bond content is preferably 0.4 mmol / g to 1.7 mmol / g, and more preferably 0.5 mmol / g to 1.2 mmol / g. When the urea bond content of the polyurethane resin (P) (polyurethane urea resin) is within the above range, the coating film (printed layer) formed by the gravure ink containing the gravure ink composition of the present invention exhibits excellent adhesion to the substrate. The urea bond content of polyurethane resin (P) is calculated using the following formula. {Isocyanate group content in organic diisocyanate (B) (mmol) - Hydroxyl group content in polyols (A1) to (A3) (mmol) - Hydroxyl group content in chain extender (F2-2) (mmol)} / Mass of polyurethane resin (P) (g) The urea bond content of the polyurethane resin (P) can be adjusted by the amount of polyol (A), organic diisocyanate (B), and chain extender (F2-2) used. Furthermore, the above formula is also applicable when using the polyol described in the examples below.

[0078] The urethane bond content and urea bond content of polyurethane resin (P) are determined by the N atom content, which is quantified by a nitrogen analyzer. 1 The amount of urethane bonds and urea bonds can be calculated from the ratio of urethane bonds to urea bonds quantified by 1H-NMR, as well as the content of allohanate and biuret groups. First, the total amount of N atoms from urethane bonds and urea bonds is calculated by subtracting the amount of N atoms from allohanate and biuret groups from the total N atom content. Next, the amount of N atoms from urethane bonds and urea bonds is calculated from the ratio of urethane bonds to urea bonds. From these values, the content of urethane bonds and urea bonds are calculated, respectively. In this specification, the urethane bond content and urea bond content of the polyurethane resin (P) are more specifically values ​​measured by the following methods.

[0079] (Method for measuring the urethane bond content and urea bond content of polyurethane resin (P)) The urethane bond content and urea bond content of polyurethane resin (P) are determined by the nitrogen atom content, which is quantified using a nitrogen analyzer [ANTEK7000 (manufactured by ANTEK)]. 1 The ratio of urethane bonds to urea bonds quantified by 1H-NMR, and the content of alohanate and biuret groups, as described later, are used to determine the composition of the urethane bond and urea bond. 1 For H-NMR measurements, the method described in "Structural study of polyurethane resin (P) by NMR: Takeda Research Institute Report 34(2), 224-323 (1975)" shall be used. That is, when an aliphatic isocyanate or alicyclic isocyanate is used as the organic diisocyanate (B), 1 By measuring with 1H-NMR, the mass ratio of urea bonds to urethane bonds is determined from the ratio of the integrated amount of hydrogen derived from urea bonds at a chemical shift of approximately 6 ppm to the integrated amount of hydrogen derived from urethane bonds at a chemical shift of approximately 7 ppm. The content of urethane bonds and urea bonds is then calculated from this mass ratio and the above-mentioned N atom content and alohanate group and biuret group content. When an aromatic isocyanate is used as organic diisocyanate (B), 1 By measuring with 1H-NMR, the mass ratio of urea bonds to urethane bonds is calculated from the ratio of the integrated amount of hydrogen derived from urea bonds at a chemical shift of approximately 8 ppm to the integrated amount of hydrogen derived from urethane bonds at a chemical shift of approximately 9 ppm. The content of urethane bonds and urea bonds is then calculated from this mass ratio and the above-mentioned N atom content and alohanate group and biuret group content.

[0080] (Content of allohanate and biuret groups) The total content of allohanate groups and biuret groups in polyurethane resin (P) is calculated by gas chromatography [Shimadzu GC-9A (Shimadzu Corporation)]. Prepare 50 g of DMF solution containing 0.01% by mass of di-n-butylamine and 0.01% by mass of naphthalene (internal standard). Weigh a sample of polyurethane resin (P) into a stoppered test tube, add 2 g of the above DMF solution, and heat the test tube in a 90°C constant temperature water bath for 2 hours. After cooling to room temperature, add 10 μL of acetic anhydride and shake for 10 minutes. Add another 50 μL of di-n-propylamine and shake for 10 minutes, then perform gas chromatography measurement under the following conditions. Simultaneously perform a blank measurement and determine the amount of amine consumed from the difference with the test value to measure the total content of allohanate groups and biuret groups.

[0081] (Gas chromatograph conditions) Equipment: Shimadzu GC-9A Column: 10% PEG-20M on Chromosorb WAW DMCS 60 / 80 mesh glass column (manufactured by GL Sciences Co., Ltd., 3mmφ x 2m) Column temperature: 160℃ Sample introduction temperature: 200℃ Carrier gas: Nitrogen 40 mL / min Detector: FID Sample injection volume: 2 μL

[0082] (Formula for calculating the total content of allohanate groups and biuret groups) The total content of allohanate groups and biuret groups can be calculated using the following formula. Total content of allohanate group and biuret group (g) = {(BA) / B} × 0.00155 / S A: (Peak area of ​​di-n-butylamine / Peak area of ​​naphthalene) of the sample B: Blank (peak area of ​​di-n-butylamine / peak area of ​​naphthalene) S: Amount of polyurethane urea resin collected (g)

[0083] The polyurethane resin (P) preferably has a 300% modulus of 18 MPa to 35 MPa, and more preferably 20 MPa to 30 MPa, as measured by the following measurement method. In this specification, the 300% modulus is the value measured as "stress at 300% elongation" as "tensile stress at a predetermined elongation" in JIS K6251. When the 300% modulus is 18 MPa or higher, the laminate having a printed layer formed using the gravure ink composition of the present invention exhibits excellent cutability. When the 300% modulus is 35 MPa or lower, the coating film formed using the gravure ink composition of the present invention exhibits excellent adhesion to the substrate.

[0084] [Method for measuring 300% modulus] A method for measuring the "stress at 300% elongation" in the "tensile stress at a given elongation" in accordance with JIS K6251, using a coating formed from a mixture obtained by mixing polyurethane resin (P), a hexamethylene diisocyanate trifunctional adduct, and a tolylene diisocyanate trifunctional adduct in a mass ratio of 3:0.5:0.5 on a solid content basis, to prepare a test specimen shaped like a dumbbell (Type 3).

[0085] The 300% modulus of the polyurethane resin (P) is, more specifically, the value measured by the method described in the examples of this specification.

[0086] "Vinyl chloride-vinyl acetate copolymer" The gravure ink composition of the present invention may further contain a vinyl chloride-vinyl acetate copolymer. The vinyl chloride-vinyl acetate copolymer is a copolymer reaction product of vinyl chloride and vinyl acetate. That is, the vinyl chloride-vinyl acetate copolymer contains vinyl chloride units and vinyl acetate units. In addition, the vinyl chloride-vinyl acetate copolymer may optionally contain monomer units other than vinyl chloride units and vinyl acetate units. The other monomers are not particularly limited as long as they can copolymerize with vinyl chloride and vinyl acetate.

[0087] The content of vinyl chloride units relative to the total mass of the vinyl chloride-vinyl acetate copolymer is preferably 80% to 95% by mass, and more preferably 86% to 93% by mass. When the content of vinyl chloride units relative to the total mass of the vinyl chloride-vinyl acetate copolymer is within the above range, good blocking resistance and toughness of the coating film can be obtained.

[0088] The content of vinyl acetate units relative to the total mass of the vinyl chloride-vinyl acetate copolymer is preferably 1% to 20% by mass, and more preferably 1% to 15% by mass. When the content of vinyl acetate units relative to the total mass of the vinyl chloride-vinyl acetate copolymer is within the above range, it is flexible and has excellent adhesion to the substrate.

[0089] The mass ratio of the polyurethane resin (P) to the vinyl chloride-vinyl acetate copolymer in the gravure ink composition of the present invention, based on solid content, is preferably 1.0:0.10 to 1.0:1.0, and more preferably 1.0:0.15 to 1.0:0.7. When the mass ratio of the polyurethane resin (P) to the vinyl chloride-vinyl acetate copolymer in terms of solid content is within the above range, the lamination suitability is excellent.

[0090] "Organic solvents" As organic solvents, known organic solvents such as aromatic organic solvents like toluene and xylene; ketone organic solvents like methyl ethyl ketone and methyl isobutyl ketone; ester organic solvents like ethyl acetate, n-propyl acetate, isopropyl acetate, and isobutyl acetate; and alcohol organic solvents like methanol, ethanol, n-propanol, isopropanol, and n-butanol can be used. Among these, organic solvents that do not contain aromatic organic solvents like toluene and xylene (non-toluene organic solvents) are more preferred. As organic solvents, one type may be used alone, or two or more types may be used in combination, but it is preferable to use a mixed solvent consisting of two or more organic solvents. From the viewpoint of the working environment, a mixed solvent of an ester organic solvent and / or a ketone organic solvent and an alcohol organic solvent is preferred, and a mixed solvent of an ester organic solvent, a ketone organic solvent, and an alcohol organic solvent is more preferred. The mixing ratio of the ester-based organic solvent and / or ketone-based organic solvent to the alcohol-based organic solvent (ester-based organic solvent and / or ketone-based organic solvent / alcohol-based organic solvent) is preferably 40 / 60 to 90 / 10 by mass.

[0091] "Other additives" The gravure ink composition of the present invention may optionally contain other additives such as leveling agents, defoaming agents, waxes, antiblocking agents, plasticizers, light stabilizers, infrared absorbers, ultraviolet absorbers, fragrances, and flame retardants.

[0092] "Other resins" The gravure ink composition of the present invention may be used in combination with resins other than the polyurethane resin (P) described above (hereinafter also referred to as "other resins" in this specification), as long as the effects of the present invention are not impaired. Examples of other resins include polyurethane resins other than the polyurethane resin (P) described above, chlorinated polypropylene resins, cellulose resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, polyamide resins, acrylic resins, polyester resins, alkyd resins, polyvinyl chloride resins, rosin resins, rosin-modified maleic acid resins, terpene resins, phenol-modified terpene resins, ketone resins, cyclized rubbers, chlorinated rubbers, butyral, petroleum resins, and modified resins thereof. These other resins may be used individually or in combination of two or more.

[0093] (Composition of gravure ink composition) The content of polyurethane resin (P) relative to the total mass of the gravure ink composition of the present invention is preferably 4% to 20% by mass, more preferably 5% to 18% by mass, and even more preferably 6% to 15% by mass. When the content of polyurethane resin (P) relative to the total mass of the gravure ink composition of the present invention is within the above range, good ink stability and substrate adhesion can be obtained. The polyurethane resin (P) content of the gravure ink composition of the present invention, relative to the total mass of solids, is preferably 10% to 85% by mass, more preferably 13% to 80% by mass, and even more preferably 15% to 75% by mass. When the polyurethane resin (P) content of the gravure ink composition of the present invention, relative to the total mass of solids, is within the above range, good ink stability and substrate adhesion can be obtained.

[0094] The content of the organic solvent relative to the total mass of the gravure ink composition of the present invention is preferably 20% to 90% by mass, more preferably 40% to 85% by mass, and even more preferably 50% to 85% by mass.

[0095] When the gravure ink composition of the present invention contains a vinyl chloride-vinyl acetate copolymer, the content of the vinyl chloride-vinyl acetate copolymer relative to the total mass of the gravure ink composition of the present invention is preferably 1% to 6% by mass, more preferably 1.3% to 5.5% by mass, and even more preferably 1.5% to 5% by mass. When the gravure ink composition of the present invention contains a vinyl chloride-vinyl acetate copolymer, the content of the vinyl chloride-vinyl acetate copolymer relative to the total mass of solids in the gravure ink composition of the present invention is preferably 3% to 30% by mass, more preferably 4% to 28% by mass, and even more preferably 4% to 25% by mass.

[0096] The gravure ink composition of the present invention may also be used as a medium. In one embodiment, when the gravure ink composition of the present invention is used as a medium, the gravure ink composition of the present invention may contain silica. The silica content relative to the total mass of the gravure ink composition of the present invention is preferably 0.1% to 2.0% by mass, more preferably 0.1% to 1.0% by mass, and even more preferably 0.1% to 0.6% by mass. When the gravure ink composition of the present invention is used as a medium, the silica solid content relative to the total mass of solids in the gravure ink composition of the present invention is preferably 0.2% to 5.0% by mass, more preferably 0.2% to 3.0% by mass, and even more preferably 0.2% to 2.5% by mass.

[0097] "Method for manufacturing a composition for gravure inks" The gravure ink composition of the present invention can be produced by mixing a polyurethane resin (P) and, optionally, a vinyl chloride-vinyl acetate copolymer in an organic solvent using a disperser or stirrer, and then mixing the resulting mixture with other resins, other additives, organic solvents, etc.

[0098] As a disperser, a bead mill is preferable. Examples of bead mills include dyno mills and sand mills. Examples of agitators include dissolvers.

[0099] The gravure ink composition of the present invention contains a polyurethane resin (P) and an organic solvent (S), wherein the polyurethane resin (P) has units based on polyol (A) and units based on organic diisocyanate (B), and the polyol (A) contains two or more types of linear polyether polyols (A1). Therefore, the printed layer formed with a gravure ink containing the gravure ink composition of the present invention exhibits excellent cutability.

[0100] <Gravure Ink> The gravure ink of the present invention comprises the gravure ink composition of the present invention, a pigment, and an isocyanate-based curing agent (E).

[0101] "Pigment" Examples of pigments include inorganic pigments and organic pigments. Examples of inorganic pigments include titanium dioxide, zinc oxide, barium sulfate, and calcium carbonate. Titanium dioxide is particularly desirable from the viewpoint of opacity. Titanium dioxide having a rutile-type crystalline structure is preferred. It is preferable that the titanium dioxide is surface-treated with at least silica and / or alumina. Having a silica and / or alumina treatment layer improves the printability of the gravure ink. Furthermore, titanium dioxide may be treated with other metals or oxides, such as elemental metals consisting of Si, Al, Zn, or Zr, or oxides of Al or Zn. "Treated" in the context of titanium dioxide refers to a state where the surface of the titanium dioxide particles is coated. The oil absorption capacity of titanium dioxide is preferably 14 mL / 100g to 40 mL / 100g, and more preferably 17 mL / 100g to 30 mL / 100g, according to the measurement method specified in JIS K5101. Furthermore, the average particle diameter (median particle diameter) measured by a transmission electron microscope is preferably 0.15 μm to 0.35 μm, and more preferably 0.20 to 0.30 μm.

[0102] Examples of organic pigments include those commonly used in gravure inks, such as soluble azo pigments, insoluble azo pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, isoindoline pigments, perylene pigments, perinone pigments, dioxazine pigments, anthraquinone pigments, dianthaquinonyl pigments, anthrapyrimidine pigments, anthancerone pigments, indanthrone pigments, flavanthrone pigments, pyrancerone pigments, and diketopyrrolopyrrole pigments. These pigments can be used individually or in combination of two or more.

[0103] Multiple types of titanium dioxide pigments may be used in combination as pigments. In addition to titanium dioxide pigment, other inorganic pigments and organic pigments can also be used in combination with the gravure ink of the present invention.

[0104] When the gravure ink of the present invention contains a coloring pigment as a pigment, the content of the coloring pigment relative to the total mass of the gravure ink of the present invention is preferably 5% to 50% by mass, more preferably 5% to 45% by mass, and even more preferably 5% to 40% by mass. When the gravure ink of the present invention contains a coloring pigment as a pigment, the content of the coloring pigment relative to the total mass of solids in the gravure ink of the present invention is preferably 15% to 75% by mass, more preferably 20% to 73% by mass, and even more preferably 25% to 73% by mass.

[0105] "Isocyanate-based curing agent (E)" A polyfunctional isocyanate compound can be used as the isocyanate-based curing agent (E). Furthermore, a trifunctional adduct is preferred as the isocyanate-based curing agent (E), with aliphatic polyisocyanates and aromatic polyisocyanates being more preferred. Examples of commercially available aliphatic polyisocyanates used as trifunctional adduct bodies include Takenate® D160N (manufactured by Mitsui Chemicals, Inc., trimethylolpropane-modified hexamethylene diisocyanate), Duranate® P301-75E (manufactured by Asahi Kasei Corporation), and Coronate® HL (manufactured by Tosoh Corporation). By using aliphatic polyisocyanates as trifunctional adduct bodies, the cohesive force of the coating film is increased, and the adhesion to the substrate is improved. Examples of commercially available aromatic polyisocyanates used as trifunctional adduct compounds include Takenate D-103 (manufactured by Mitsui Chemicals, Inc., trimethylolpropane-modified tolylene diisocyanate) and Coronate L (manufactured by Tosoh Corporation). Using aromatic polyisocyanates as trifunctional adduct compounds improves blocking resistance and cutability.

[0106] The isocyanate-based curing agent (E) preferably contains a hexamethylene diisocyanate (HDI) derivative and / or a tolylene diisocyanate (TDI) derivative. Examples of hexamethylene diisocyanate (HDI) derivatives include trimethylolpropane-modified hexamethylene diisocyanate. Examples of tolylene diisocyanate (TDI) derivatives include trimethylolpropane-modified tolylene diisocyanate. The isocyanate-based curing agent (E) may be used alone or in combination of two or more types. The content of the hexamethylene diisocyanate derivative relative to the total mass of the isocyanate-based curing agent (E) is preferably 30% to 100% by mass. When the content of the hexamethylene diisocyanate derivative relative to the total mass of the isocyanate-based curing agent (E) is within the above range, the laminate strength of the laminate is improved.

[0107] The content of the tolylene diisocyanate derivative relative to the total mass of the isocyanate-based curing agent (E) is preferably 30% to 100% by mass, and more preferably 40% to 100% by mass. When the content of the tolylene diisocyanate derivative relative to the total mass of the isocyanate-based curing agent (E) is within the above range, blocking resistance and cutability are improved. The content of isocyanate-based curing agent (E) per 100 parts by mass of polyurethane resin (P) is preferably 15 to 50 parts by mass, and more preferably 20 to 40 parts by mass. When the content of isocyanate-based curing agent (E) per 100 parts by mass of polyurethane resin (P) is within the above range, both substrate adhesion and cutability can be achieved.

[0108] Furthermore, it is also preferable that the isocyanate-based curing agent (E) consists of only two types: a hexamethylene diisocyanate derivative and a tolylene diisocyanate derivative. By appropriately changing the mixing ratio of these two types of isocyanate-based curing agents (E), the laminate strength, substrate adhesion, and cutability can be adjusted to the desired level.

[0109] The gravure ink of the present invention contains the gravure ink composition of the present invention, a pigment, and an isocyanate-based curing agent (E), and therefore the printed layer formed from the gravure ink of the present invention has excellent cutability.

[0110] "Method of manufacturing gravure ink" The gravure ink of the present invention can be produced, for example, by mixing the gravure ink composition of the present invention, a pigment, and an isocyanate-based curing agent (E) using a disperser or a stirrer. The pigment contained in the gravure ink of the present invention may be one that is already contained in the gravure ink composition of the present invention. That is, the gravure ink of the present invention can also be produced by mixing the gravure ink composition of the present invention containing a pigment and an isocyanate-based curing agent (E) using a disperser or a stirrer. Examples of dispersers and stirrers include those described in the "Method for Manufacturing Gravure Ink Compositions" above. The particle size distribution of the pigment in the gravure ink of the present invention can be adjusted by appropriately adjusting the size of the pulverizing media in the disperser, the filling rate of the pulverizing media, the dispersion processing time, the discharge speed of the gravure ink, the viscosity of the gravure ink, and so on.

[0111] <Laminated structure> The laminate of the present invention has a printed layer formed from the gravure ink of the present invention. The laminated structure of the present invention will be described below with reference to Figure 1. Figure 1 is a cross-sectional view showing an example of the laminated structure of the present invention.

[0112] As shown in Figure 1, the laminate 10 of the present invention comprises at least a first substrate 11, a printed layer 12, and a second substrate 14. The printed layer 12 is formed on one side (top surface) 11a of the first substrate 11. An adhesive layer 13 is formed on the side (top surface) 12a of the printed layer 12 opposite to the side in contact with the first substrate 11. A second substrate 14 is provided on the side (top surface) 13a of the adhesive layer 13 opposite to the side in contact with the printed layer 12. In other words, the laminate 10 of the present invention is constructed by laminating the first substrate 11, the printed layer 12, the adhesive layer 13, and the second substrate 14 in this order.

[0113] Examples of the first substrate 11 include polyester films such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN); polyolefin films such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), and polypropylene (PP); cellulose films such as cellophane; polystyrene (PS) films; ethylene-vinyl acetate copolymer resin films; ethylene-vinyl alcohol copolymer resin films; polyamide films such as nylon (NY) films; polycarbonate films; polyimide films; polyvinyl chloride films; and the like. Both stretched and unstretched plastic films, such as biaxially oriented PP films and unstretched PP films, can be used. Furthermore, substrates with a metal vapor deposition layer such as aluminum vapor deposition, or substrates with a transparent vapor deposition layer such as alumina and silica, can also be used. In addition, the surface of the first substrate may be subjected to various surface treatments such as corona discharge treatment, plasma treatment, flame treatment, solvent treatment, and coating treatment, as well as various decorations such as printing with colored inks.

[0114] Examples of the second base material 14 include polyethylene, polypropylene, and other polyolefin base materials, or film-like sealants made of composite materials thereof.

[0115] The adhesive layer 13 is formed by applying and drying the adhesive. Preferably, a two-component adhesive consisting of a mixture of a polyol and an isocyanate curing agent is used as the adhesive. Examples of polyols include polyester-based and polyether-based polyols. Specifically, examples include TM-250HV / CAT-RT86L-60, TM-550 / CAT-RT37, and TM-314 / CAT-14B manufactured by Toyo Morton Co., Ltd.

[0116] "Method for manufacturing laminated structures" The laminated structure of the present invention is obtained, for example, by printing gravure ink onto the upper surface 11a of a first substrate 11 to form a printed layer 12, forming an adhesive layer 13 on the upper surface 12a of the printed layer 12, and bonding (laminating) the first substrate 11 and the second substrate 14 via the adhesive layer 13. For lamination, known lamination methods such as dry lamination and extrusion lamination are used. Dry lamination is a method in which an adhesive is applied to the printed layer of the printed material or to the sealant and dried, and the printed material and sealant are pressed together to form a laminate. Extrusion lamination is a method in which molten resin is laminated via an anchor coating layer as needed. The thickness of the laminate is preferably, for example, 1 to 300 μm, more preferably 5 to 200 μm, and particularly preferably 10 to 100 μm.

[0117] The laminate 10 of the present invention has a printed layer 12 formed from the gravure ink of the present invention, and therefore has superior cutability compared to conventional laminates having a printed layer formed from gravure ink.

[0118] Furthermore, the technical scope of the present invention is not limited to the above-described content, and various modifications can be made without departing from the spirit of the present invention.

[0119] Furthermore, it is possible to replace the components described above with well-known components as appropriate, without departing from the spirit of the present invention, and the modifications described above may be combined as appropriate.

[0120] This specification discloses the following: <1> A gravure ink composition comprising a polyurethane resin (P) and an organic solvent (S), wherein the polyurethane resin (P) has units based on a polyol (A) and units based on an organic diisocyanate (B), and the polyol (A) contains two or more linear polyether polyols (A1). <2> The polyol (A) further contains a polyester polyol (A2) having units based on a polycarboxylic acid and units based on a polyol. <1> The gravure ink composition described above. <3> The polyester polyol (A2) is a polyester polyol having units based on a dicarboxylic acid (C) and units based on a diol (D), wherein the dicarboxylic acid (C) contains sebacic acid (c1), the diol (D) contains 1,3-propanediol (d1), the content of units based on sebacic acid (c1) relative to the total amount of units based on the dicarboxylic acid (C) is 10 to 100% by mass, and the content of units based on 1,3-propanediol (d1) relative to the total amount of units based on the diol (D) is 10 to 100% by mass. <2> The gravure ink composition described above. <4> The polyurethane resin (P) has hydroxyl groups in at least its side chains and has a hydroxyl value of 1 to 45 mgKOH / g, <1> ~ <3> A gravure ink composition as described in any of the above. <5> The polyurethane resin (P) has a urethane bond content of 1.1 to 2.2 mmol / g, <1> ~ <4> A gravure ink composition as described in any of the above. <6> The polyurethane resin (P) has a urea bond content of 0.4 to 1.7 mmol / g, <1> ~ <5> A gravure ink composition as described in any of the above. <7> The polyurethane resin (P) has a 300% modulus of 18-35 MPa as measured by the following measurement method. <1> ~ <6> A gravure ink composition as described in any of the above. [Method for measuring 300% modulus] A method for measuring the "stress at 300% elongation" in the "tensile stress at a given elongation" in accordance with JIS K6251, using a coating formed from a mixture obtained by mixing the aforementioned polyurethane resin (P), a hexamethylene diisocyanate trifunctional adduct, and a tolylene diisocyanate trifunctional adduct in a mass ratio of 3:0.5:0.5 on a solid content basis, to prepare a test specimen shaped like a dumbbell (Type 3), and measuring the "stress at 300% elongation" in the "tensile stress at a given elongation". <8> The above further contains a vinyl chloride-vinyl acetate copolymer, wherein the mass ratio of the polyurethane resin (P) to the vinyl chloride-vinyl acetate copolymer on a solid content basis is 1.0:0.10 to 1.0:1.0. <1> ~ <7> A gravure ink composition as described in any of the above. <9> the above <1> ~ <8> A gravure ink comprising a gravure ink composition described in any of the above, a pigment, and an isocyanate-based curing agent (E). <10> The isocyanate-based curing agent (E) comprises a hexamethylene diisocyanate derivative and / or a tolylene diisocyanate derivative, <9> Gravure ink as described. <11> the above <9> or <10> A laminate having a printed layer formed from the gravure ink described above. [Examples]

[0121] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0122] [Raw materials used 1] The raw materials used in the manufacturing examples and comparative manufacturing examples described later are as follows: Linear polyether polyol (A1) • ECOTRION (registered trademark) H2000: Biomass-derived polytrimethylene ether glycol with Mn=2,000 [Manufactured by SK Chemicals] • Bio(registered trademark) PTMG2000: Polytetramethylene ether glycol derived from biomass with Mn=2,000 [Manufactured by Mitsubishi Chemical Corporation] • PEG-600: Polyethylene glycol with Mn=600 [Manufactured by Sanyo Chemical Industries, Ltd.] Other polyether polyols • Sannix (registered trademark) PP-2000: Polypropylene glycol with Mn=2,000 [Manufactured by Sanyo Chemical Industries, Ltd.] In the manufacturing examples and comparative manufacturing examples described later, raw materials that are not explicitly stated to be biomass-derived are not biomass-derived raw materials.

[0123] [Raw materials used 2] The raw materials used in the examples and comparative examples described below are as follows. Vinyl chloride-vinyl acetate copolymer: Product name "Solvine (registered trademark) TA5R" (manufactured by Nisshin Chemical Industry Co., Ltd., vinyl chloride unit content: 87.5% by mass, vinyl acetate unit content: 1% by mass) Titanium dioxide: Product name "Titanix JR-806" (manufactured by Teika Co., Ltd.) Copper phthalocyanine blue: (Manufactured by Dainichi Seika Kogyo Co., Ltd., CI Name "PB-15:3") Polyisocyanate-based curing agent (i): A 50% solids solution obtained by diluting trimethylolpropane-modified hexamethylene diisocyanate (Takenate D160N, manufactured by Mitsui Chemicals, Inc.) with ethyl acetate. Polyisocyanate-based curing agent (ii): A 50% solids solution obtained by diluting trimethylolpropane-modified tolylene diisocyanate (Takenate D103, manufactured by Mitsui Chemicals, Inc.) with ethyl acetate.

[0124] The measurement methods for the physical properties shown in Tables 1-5 below, and the evaluation methods for the evaluation items, are as follows.

[0125] [Hydroxyl value, acid value, Mn, and biomass concentration of polyester polyol (A2)] The hydroxyl value of polyester polyol (A2) was measured in accordance with JIS K0070-1992. The acid value of polyester polyol (A2) was measured in accordance with JIS K0070-1992. The manganese content of polyester polyol (A2) was measured by gel permeation chromatography (GPC) under the following conditions. (Measurement conditions) Equipment: "Waters Alliance 2695" [manufactured by Waters] Column: "TSKgel guardcolumn Super HL" (manufactured by Tosoh Corporation, 1 piece) (composed of one each of TSKgel SuperH2000, TSKgel SuperH3000, and TSKgel SuperH4000 (all manufactured by Tosoh Corporation) linked together) Sample solution: 0.25% by mass tetrahydrofuran solution Solution injection volume: 10μL Flow rate: 0.6mL / min Measurement temperature: 40℃ Detection device: Refractive index detector Reference substance: Standard polyethylene glycol The biomass concentration of polyester polyol (A2) was calculated as the mass ratio of biomass-derived raw materials constituting polyester polyol (A2) to the mass of polyester polyol (A2).

[0126] [Hydroxyl value, urethane bond content, urea bond content, and biomass concentration of polyurethane resin (P)] The hydroxyl value of polyurethane resin (P) was measured in accordance with JIS K0070-1992. The urethane bond content and urea bond content of the polyurethane resin (P) were measured by the method described above in (Content of urethane bond and urea bond of polyurethane resin (P)). The biomass concentration of polyurethane resin (P) was calculated as the mass ratio of biomass-derived raw materials constituting the polyurethane resin (P) to the total mass of the polyurethane resin (P).

[0127] [300% modulus of a coating formed from polyurethane resin (P)] A mixture was obtained by mixing polyurethane resin (P) (urethane resin varnishes A to L described later), a hexamethylene diisocyanate trifunctional adduct, and a tolylene diisocyanate trifunctional adduct in a mass ratio of 3:0.5:0.5 on a solid content basis. The obtained mixture was diluted with toluene to adjust the solid content concentration to 20% by mass. The solution was then gently poured into a polypropylene mold with a release film attached, so that the film thickness was approximately 200 μm. The mixture was spread uniformly, left to stand at 25°C for 12 hours, dried at 70°C for 1 hour using a circulating air dryer, and then further dried under reduced pressure at 105°C and 1.3 kPa for 1 hour to obtain a dried film. From the obtained coating, test specimens were prepared in the shape of dumbbell type 3 using a Super Dumbbell Cutter [manufactured by Dumbbell Co., Ltd.] in accordance with JIS K6250. The 300% modulus of the prepared test specimens was measured at a tensile speed of 500 mm / min using an Autograph [AGS-500D manufactured by Shimadzu Corporation] in accordance with JIS K6251. In this specification, "solid content concentration" means the mass ratio of the residue after heating and drying 1 g of the substance described herein at 130°C for 45 minutes using a circulating air dryer, to the mass of the substance before heating and drying.

[0128] [Evaluation criteria] <Cutting properties> The cutability of the laminated structures of the examples and comparative examples was evaluated by a sensory test in which a cutter was used to make a starting point at the edge of the printed area, perpendicular to the print, and then the structure was torn by hand. The evaluation criteria were as follows. A result of A or B was considered to indicate a usable level (passing grade). A: It cuts without resistance. B: There is a slight resistance, but it cuts through. C: It has strong resistance and breaks while stretching. D: It is difficult to cut.

[0129] <Ink Stability> 100 parts by mass of the gravure ink compositions of the examples and comparative examples were diluted with a mixed solvent ("SH NO2 Solvent (S)", manufactured by Dainichi Seika Kogyo Co., Ltd.) in a ratio of EA / MEK / IPA = 4 / 4 / 2 (by mass) so that the viscosity at 20°C was 16 seconds, as measured using a Zahn cup No. 3 (manufactured by Rigosha Co., Ltd.), to obtain diluted inks. The viscosity (V1) of the gravure ink at 20°C immediately after adding 3 parts by mass of polyisocyanate curing agent (i) (a 50% solids solution of hexamethylene diisocyanate adduct) and 3 parts by mass of polyisocyanate curing agent (ii) (a 50% solids solution of tolylene diisocyanate adduct) to the obtained diluted ink, and the viscosity (V2) of the gravure ink at 20°C after being stored at 20°C for 24 hours, were measured using a Zahn cup No. 3 (manufactured by Rigosha Co., Ltd.), and the viscosity increase (viscosity (V2) - viscosity (V1)) was calculated. Ink stability was evaluated according to the following evaluation criteria. Ink stability is an indicator of the fluidity of gravure ink; the shorter the viscosity increase, that is, the better the ink stability, the better the fluidity. The evaluation criteria were as follows. A result of A or B was considered to indicate a usable level (passing grade). A: The viscosity increase is less than 1 second. B: The viscosity increase is between 1 second and 5 seconds. C: Viscosity increase is between 5 seconds and 10 seconds. D: Viscosity increase is 10 seconds or more.

[0130] <Adhesion to substrate> Cellophane adhesive tape (manufactured by Nichiban Co., Ltd., 18 mm wide) was applied to the printed layer of the laminated bodies of the examples and comparative examples. After the cellophane adhesive tape was removed, the adhesion of the printed layer to the substrate was evaluated according to the following criteria. The evaluation criteria were as follows. An evaluation result of A to B was considered to be at a usable level (pass). In the evaluation of substrate adhesion, the peel area refers to the percentage of the area of ​​the printed layer that has peeled off relative to the area of ​​the printed layer to which the cellophane adhesive tape was attached. A: The peeling area is less than 10%. B: The peeling area is 10% or more but less than 30%. C: The peeling area is 30% or more but less than 50%. D: The peeling area is 50% or more.

[0131] <Low temperature stability> The gravure ink compositions of the examples and comparative examples were temperature-controlled for one day in a constant temperature incubator set to -5°C, 0°C, and 5°C. The gravure ink compositions were scraped off with a spatula, and the presence or absence of precipitates in the gravure ink compositions was visually confirmed. The low-temperature stability was evaluated according to the following criteria. The evaluation criteria were as follows. A result of A or B was considered to indicate a usable level (passing grade). A: No precipitate at -5℃ B: Precipitates present at -5°C, no precipitates at 0°C. C: Precipitates present at 0°C, no precipitates at 5°C D: Precipitation present at 5℃

[0132] <Printability> Using a gradient plate, the gravure ink compositions of the examples and comparative examples were printed onto a 25 μm thick PET film (manufactured by Toyobo Co., Ltd.) at a speed of 100 m / min. The gradient plate had multiple cells with different capacities (depths) (each with capacities of 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, or 5%). By printing the gravure ink compositions onto the PET film using the gradient plate, in which the gravure ink compositions were injected into each cell, printed materials were obtained with multiple printed layers of different thicknesses depending on the capacity (depth) of each cell. The obtained printed materials were visually observed to check the appearance of highlights and evaluate the presence or absence of streaking. The evaluation criteria were as follows. A result of A or B was considered to indicate a usable level (passing grade). A: No smudging was observed in any of the printing layers corresponding to each cell. B: Streaking was observed in the printed layer corresponding to cells with a capacity of 5%. C: Smudging was observed in the printed layer corresponding to cells with a capacity of 10%. D: Streaking was observed in the printed layer corresponding to cells with a capacity of 20% or more.

[0133] <Blocking resistance> Printed materials of the examples and comparative examples were cut to prepare test specimens measuring 5 cm x 5 cm. The prepared test specimens were stacked so that the surface of the printed layer and the surface of the first substrate were in contact to obtain laminated test specimens. 7 kgf / cm² was applied to the obtained laminated test specimens. 2 The samples were subjected to a load and stored for 24 hours under conditions of 40°C and 80% RH. After storage, the laminated test specimens were separated from each other, and the peel resistance was checked. The presence and degree of peeling of the printed layer (peeling area) was also observed to evaluate the blocking resistance. In the evaluation of blocking resistance, the peeling area refers to the percentage of the area of ​​the peeled printed layer relative to the area of ​​the test specimen. The evaluation criteria were as follows. A result of A to B was considered to indicate a usable level (pass). Furthermore, there was a tendency for peeling resistance to be stronger as the peeling area of ​​the printed layer increased. A: The printed layer did not peel off, and there was no resistance to peeling. B: Less than 10% of the printed layer peeled off, and there was slight resistance to peeling. C: Between 10% and 30% of the printed layer peeled off, and there was resistance to peeling. D: More than 30% of the printed layer peeled off, and there was strong resistance to peeling.

[0134] [Manufacturing Example 1] In a four-necked flask equipped with a refluxer, thermometer, nitrogen inlet tube, and stirrer, 232 parts of biomass-derived 1,3-propanediol, 55 parts of biomass-derived 1,4-butanediol, 64 parts of biomass-derived neopentyl glycol, 311 parts of biomass-derived sebacic acid, and 338 parts of adipic acid were charged. Under atmospheric pressure, nitrogen gas was passed through, and esterification was carried out at 190°C to 210°C while distilling off water until the acid value became 1 or less, yielding polyester polyol (A2-1). The hydroxyl value, acid value, Mn, and biomass concentration of polyester polyol (A2-1) were measured by the method described above, and the hydroxyl value was 56.0 mgKOH / g, the acid value was 0.3 mgKOH / g, the Mn was 2,000, and the biomass concentration was 62% by weight.

[0135] [Manufacturing Example 2] Polyester polyol (A2-2) was obtained in the same manner as in Production Example 1, except that the raw materials were changed to 184 parts of biomass-derived 1,3-propanediol, 54 parts of petroleum-derived 1,4-butanediol, 126 parts of biomass-derived neopentyl glycol, 369 parts of biomass-derived sebacic acid, and 267 parts of adipic acid. The hydroxyl value, acid value, Mn, and biomass concentration of polyester polyol (A2-2) were measured by the method described above, and the hydroxyl value was 74.8 mgKOH / g, the acid value was 0.4 mgKOH / g, the Mn was 1,500, and the biomass concentration was 60% by weight.

[0136] [Manufacturing Example 3] Polyester polyol (A2-3) was obtained in the same manner as in Production Example 1, except that the raw materials were changed to 183 parts of biomass-derived 1,3-propanediol, 183 parts of biomass-derived neopentyl glycol, 317 parts of biomass-derived sebaciate, and 317 parts of adipic acid. The hydroxyl value, acid value, Mn, and biomass concentration of polyester polyol (A2-3) were measured by the method described above, and the hydroxyl value was 56.0 mgKOH / g, the acid value was 0.6 mgKOH / g, the Mn was 2,000, and the biomass concentration was 57% by weight.

[0137] Table 1 shows the raw materials used, hydroxyl value, acid value, Mn, and biomass concentration of the polyester polyols (A2-1) to (A2-3) produced in Production Examples 1 to 3.

[0138] [Table 1]

[0139] [Manufacturing Example 4] In a reactor equipped with a stirring device, 59.9 parts of ECOTRION H2000, 79.9 parts of BioPTMG2000, 59.9 parts of polyester polyol (A2-1) synthesized in Production Example 1, 9.90 parts of petroleum-derived 1,4-butanediol, and 75.0 parts of IPDI were charged and reacted under a nitrogen atmosphere at 110°C for 6 hours to obtain a urethane prepolymer with an isocyanate group content of 3.71% by mass. After cooling to 40°C, 466 parts of ethyl acetate were added to obtain a homogeneous solution. Next, 234 parts of isopropanol were added and stirred until homogeneous. Then, 9.68 parts of aminoethylethanolamine, 0.96 parts of diethylenetriamine, and 4.88 parts of diethanolamine were added, and the mixture was reacted at 40°C for 1 hour to obtain a polyurethane resin (P) solution (urethane resin varnish A), which is a binder for printing inks of the present invention, with a biomass concentration of 58% by mass and a solid content of 30% by mass.

[0140] [Manufacturing Examples 5-9 and Comparative Manufacturing Examples 1-6] In Production Example 4, the reaction was carried out in the same manner as in Production Example 4, except that the types and amounts of raw materials used were changed to those listed in Tables 2 and 3. Specifically, a linear polyether polyol (A1), polyester polyol (A2), organic diisocyanate (B), and chain extender (F2) were reacted to obtain a urethane prepolymer, then an organic solvent (S) was added, followed by the reaction of a chain extender (F1) and a reaction stopper (G) to obtain a polyurethane resin (P) solution (urethane resin varnish B-L) with a solid content of 30% by mass. In Production Example 6 and Comparative Production Example 3, the branched polyether polyol was added simultaneously with the linear polyether polyol (A1). In Production Examples 7-9 and Comparative Production Examples 4-5, methyl ethyl ketone was used in place of ethyl acetate in Production Example 1.

[0141] For the urethane resin varnishes A to L obtained in Production Examples 4 to 9 and Comparative Production Examples 1 to 6, the hydroxyl value of the polyurethane resin (P), the urethane bond content, the urea bond content, the biomass concentration, and the 300% modulus were measured using the method described above. The results are shown in Tables 2 and 3.

[0142] [Table 2]

[0143] [Table 3]

[0144] [Example 1] "Preparation of compositions for gravure inks" Composition 1 for gravure ink was prepared by mixing urethane resin varnish A, vinyl chloride-vinyl acetate copolymer, pigment, and organic solvent in the quantities shown in Table 4, and then dispersing them in a bead mill. The content shown in Table 4 represents the percentage (mass%) of the total mass of gravure ink composition 1. As the organic solvent, a mixture of ethyl acetate (EA), methyl ethyl ketone (MEK), and isopropanol (IPA) was used in a mass ratio of 4:4:2.

[0145] "Fabrication of laminated structures" 100 parts by mass of the obtained gravure ink composition 1 was diluted with a mixed solvent of EA / MEK / IPA = 4 / 4 / 2 (by mass ratio) ("SH NO2 Solvent (S)", manufactured by Dainichi Seika Kogyo Co., Ltd.) to obtain a diluted ink. The viscosity of the obtained diluted ink was measured at 20°C using a Zahn cup No. 3 (manufactured by Rigosha Co., Ltd.) and was 16 seconds. To this diluted ink, 3 parts by mass each of polyisocyanate curing agent (i) (a 50% by mass solution of hexamethylene diisocyanate trifunctional adduct) and polyisocyanate curing agent (ii) (a 50% by mass solution of tolylene diisocyanate trifunctional adduct) were added, and the mixture was stirred with a dissolver for 1 minute to obtain the gravure ink of Example 1. As the first substrate, a corona discharge treated PET film (product name "Ester E5102", manufactured by Toyobo Co., Ltd., 12 μm thick) was prepared. Using a Helio 175-line gravure printing plate, the gravure ink of Example 1 was applied to the treated side of the substrate film by gravure printing to form a printed layer and obtain a printed material. Apply a dry laminating adhesive (Seikabond® A159 / C89(F) manufactured by Dainichi Seika Kogyo Co., Ltd.) to the resulting printed material at a dry application rate of 3 g / m². 2 The material was coated and dried using gravure printing, then heat-pressed with an LLDPE film (manufactured by Futamura Chemical Co., Ltd., product name "LL-XMTN"), and aged at 40°C for 48 hours to obtain the laminated structure of Example 1. The evaluation results are shown in Table 4.

[0146] [Examples 2-15, Comparative Examples 1-6] Gravure inks for Examples 2-15 and Comparative Examples 1-6 were prepared in the same manner as in Example 1, except that urethane resin varnishes A to L, vinyl chloride-vinyl acetate copolymer, pigment, and organic solvent were mixed in the quantities shown in Tables 4 and 5. Furthermore, the printed materials and laminated structures of Examples 2-15 and Comparative Examples 1-6 were prepared in the same manner as in Example 1, except that the gravure inks of Examples 2-15 and Comparative Examples 1-6 were used instead of the gravure ink of Example 1.

[0147] The gravure ink compositions 1 to 21 obtained in Examples 1 to 15 and Comparative Examples 1 to 6 were evaluated for printability, ink stability, and low-temperature stability using the method described above. Furthermore, the blocking resistance of the printed materials obtained in Examples 1 to 15 and Comparative Examples 1 to 6 was evaluated using the method described above. In addition, the cutability and substrate adhesion of the laminated materials obtained in Examples 1 to 15 and Comparative Examples 1 to 6 were evaluated using the method described above. The evaluation results are shown in Tables 4 and 5.

[0148] [Table 4]

[0149] [Table 5]

[0150] The results shown in Tables 4 and 5 confirm that gravure ink compositions 1 to 15 obtained in Examples 1 to 15 exhibit excellent printability, ink stability, and low-temperature stability; printed materials produced using gravure ink compositions 1 to 15 exhibit excellent blocking resistance; and laminate laminates produced using gravure ink compositions 1 to 15 exhibit excellent cutability and substrate adhesion. [Industrial applicability]

[0151] The gravure ink composition of the present invention is suitably applicable to packaging bags where cutability is essential. [Explanation of symbols]

[0152] 10 Laminated structures 11 First base material 11a One side (top side) of the first substrate 12 printing layer 12a The surface (top surface) of the printed layer opposite to the surface in contact with the first substrate. 13 Adhesive layer 13a The side of the adhesive layer opposite to the side in contact with the printed layer (top surface) 14 Second base material

Claims

1. The material contains a polyurethane resin (P) and an organic solvent (S), wherein the polyurethane resin (P) has units based on a polyol (A) and units based on an organic diisocyanate (B), and the polyol (A) contains two or more linear polyether polyols (A1). The two or more linear polyether polyols (A1) are each alkylene oxide adducts with 2 to 12 carbon atoms to a linear diol with a number-average molecular weight of less than 500. The linear diols having a number average molecular weight of less than 500 include ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, or 1,6-hexanediol. The aforementioned alkylene oxide having 2 to 12 carbon atoms comprises 1,3-propylene oxide, tetrahydrofuran, or α-olefin oxide, and is a composition for gravure ink.

2. The gravure ink composition according to claim 1, wherein the polyol (A) further contains a polyester polyol (A2) having units based on a polycarboxylic acid and units based on a polyol.

3. The composition for gravure ink according to claim 2, wherein the polyester polyol (A2) is a polyester polyol having units based on a dicarboxylic acid (C) and units based on a diol (D), the dicarboxylic acid (C) contains sebacic acid (c1), the diol (D) contains 1,3-propanediol (d1), the content of the units based on sebacic acid (c1) relative to the total amount of units based on the dicarboxylic acid (C) is 10 to 100% by mass, and the content of the units based on 1,3-propanediol (d1) relative to the total amount of units based on the diol (D) is 10 to 100% by mass.

4. The gravure ink composition according to any one of claims 1 to 3, wherein the polyurethane resin (P) has hydroxyl groups in at least its side chains and has a hydroxyl value of 1 to 45 mgKOH / g.

5. The gravure ink composition according to any one of claims 1 to 3, wherein the polyurethane resin (P) has a urethane bond content of 1.1 to 2.2 mmol / g.

6. The gravure ink composition according to any one of claims 1 to 3, wherein the polyurethane resin (P) has a urea bond content of 0.4 to 1.7 mmol / g.

7. The gravure ink composition according to any one of claims 1 to 3, wherein the polyurethane resin (P) has a 300% modulus of 18 to 35 MPa as measured by the following measurement method. [Method for measuring 300% modulus] A method for preparing a test specimen shaped like a dumbbell (Type 3) using a coating formed from a mixture obtained by mixing the aforementioned polyurethane resin (P), a hexamethylene diisocyanate trifunctional adduct, and a tolylene diisocyanate trifunctional adduct in a mass ratio of 3:0.5:0.5 on a solid content basis, and measuring the "stress at 300% elongation" in the "tensile stress at a predetermined elongation" in accordance with JIS K6251.

8. A gravure ink composition according to any one of claims 1 to 3, further comprising a vinyl chloride-vinyl acetate copolymer, wherein the mass ratio of the polyurethane resin (P) to the vinyl chloride-vinyl acetate copolymer on a solid content basis is 1.0:0.10 to 1.0:1.

0.

9. A gravure ink comprising the gravure ink composition according to any one of claims 1 to 3, a pigment, and an isocyanate-based curing agent (E).

10. The gravure ink according to claim 9, wherein the isocyanate-based curing agent (E) comprises a hexamethylene diisocyanate derivative and / or a tolylene diisocyanate derivative.

11. A laminate having a printed layer formed from the gravure ink described in claim 9.

Images