Ink composition for soft packaging laminates, printed matter, laminate, or package

Abstract

Provided is an ink composition for soft packaging laminates, the ink composition comprising: a urethane resin (A) that is obtained from a raw reaction material (I) including an organic diisocyanate compound (a1) and a polyol (a2) having a number average molecular weight (Mn) of 700-900, and that has a number average molecular weight of 1000-3000; and a urethane resin (B) which is obtained from a raw reaction material (II) that at least includes an aromatic polyisocyanate compound (b1) and a polyester polyol (b2). With this ink composition, it is possible to provide an ink composition for soft packaging laminates, which is capable of forming an ink layer that has excellent PEEL strength and dry laminate strength.

Description

Ink compositions for flexible packaging lamination, printed materials, laminates or packaging

[0001] This disclosure relates to an ink composition for flexible packaging lamination, printed materials, laminates, or packaging.

[0002] Gravure inks or flexographic inks are widely used to impart aesthetic appeal and functionality to substrates. When these substrates are used as packaging materials, particularly food packaging, lamination is commonly applied. In this case, depending on the type of contents or intended use, various substrates and lamination processes are used, such as front-side printing (printing from the front of the plastic film, etc.) or back-side printing (reversing the orientation of the print or the order of colors). Conventionally, polyurethane resin and vinyl chloride-vinyl acetate copolymer (PVC) resin have been widely used as binder resins for such lamination processes, offering both excellent dispersibility and high film properties. This combination of polyurethane resin and vinyl chloride-vinyl acetate copolymer (PVC) resin is an essential ink raw material for achieving good printability and the various properties required for lamination inks (adhesion to the substrate, lamination strength, and boil-retort suitability).

[0003] However, in response to the trend of building a circular economy that reduces substances that can have adverse effects on human health or the environment, as exemplified by the Sustainable Development Goals, legal regulations surrounding food packaging materials are becoming stricter worldwide. In particular, in recent years, there has been a demand for stricter regulations on the components used in packaging and their migration to food. Furthermore, the movement to reduce plastic is accelerating, and the demand for recyclable packaging is increasing. Therefore, in the development of gravure ink products, it has become necessary to design inks and packaging components using materials that ensure safety for human health and the environment. Among these, vinyl chloride-vinyl acetate copolymer (PVC) is a substance of concern as it hinders packaging recycling for the following reasons (a) and (b): (a) Chlorine-based resins such as vinyl chloride can cause corrosion of equipment or piping due to the desorption of hydrogen chloride and the generation of hydrochloric acid during the thermal decomposition process of recycling. (b) In thermal recycling, which reuses energy generated when waste is incinerated, incinerating chlorine-based resins can release endocrine disruptors such as dioxins. Therefore, the development of environmentally friendly inks, such as chlorine-free and PVC-free inks, will be required in the future. In addition, the ink performance required for gravure inks or flexographic inks includes adhesion to films, blocking resistance to prevent printed materials from sticking together, abrasion resistance, and heat resistance (see Patent Documents 1 and 2).

[0004] Japanese Patent Publication No. 2005-272585 Japanese Patent Publication No. 2018-131624

[0005] Patent Document 1 discloses a technology using a biomass-derived polyurethane urea resin containing biomass-derived components as an environmentally friendly ink. The characteristics of this resin are described as not impairing printability during printing, possessing the blocking resistance, film adhesion, solvent resistance, and plate clogging resistance necessary for reverse printing, and also having good laminating properties. Patent Document 2 discloses a technology for a gravure printing ink composition for front printing containing a cellulose derivative and a polyurethane resin, which has a solvent composition that does not contain aromatic hydrocarbon solvents, yet possesses excellent printability and exhibits good adhesion, heat resistance, and blocking resistance to a wide range of films. However, the technologies described in Patent Documents 1 and 2 have insufficient blocking resistance, film adhesion, and laminating properties. Furthermore, since the applications of packaging are diverse, laminating inks are required to possess boil-retort suitability in addition to the above characteristics, and further improvements are needed.

[0006] Therefore, the object of this disclosure is to provide an ink composition for flexible packaging lamination that can form an ink layer with excellent fluidity, adhesion, blocking resistance, PEEL strength, dry lamination strength, boil resistance, and retort resistance.

[0007] Therefore, the present inventors diligently studied to solve the above problems and found that by using a urethane resin (A) using a predetermined organic diisocyanate compound (a1) and a predetermined polyol (a2) as reaction raw materials, and a urethane resin (B) using an aromatic polyisocyanate compound (b1) and a polyester polyol (b2) as reaction raw materials (II), an ink layer with excellent adhesion, blocking resistance, PEEL strength, and dry lamination strength can be formed, and thus the present invention described in any of (1) to (12) below has been completed. Furthermore, this disclosure mainly relates to a printing ink composition for reverse printing, and since it can exhibit predetermined ink performance without using vinyl chloride-vinyl acetate copolymer (PVC), it is also useful for reducing environmental impact.

[0008] [1] The present disclosure provides an ink composition for flexible packaging lamination, comprising a urethane resin (A) having a number average molecular weight of 1,000 to 3,000, with an organic diisocyanate compound (a1) and a polyol (a2) having a number average molecular weight (Mn) of 700 to 900 as reaction raw materials (I), and a urethane resin (B) having at least an aromatic polyisocyanate compound (b1) and a polyester polyol (b2) as reaction raw materials (II).

[0009] [2] The urethane resin (A) is the following general formula (I):

[0010] (In the above general formula (I), R ３ and R ４ The laminating ink composition for flexible packaging according to [1], having a substructure represented by ) where each of them independently represents an aromatic group having 6 to 15 carbon atoms which is a structural unit derived from the polyol (a2), and M represents a divalent organic group which is a structural unit of the organic diisocyanate compound (a1).

[0011] [3] In the general formula (I), M represents an alkylene group having 1 to 12 carbon atoms or an arylene group having 6 to 12 carbon atoms, and the alkylene group contains one or more -CH groups. ２ The - group may be substituted with -O- or -C(=O)-, as described in [1] or [2], for the flexible packaging laminating ink composition.

[0012] [4] The urethane resin (B) is a urethane resin having a urea bond, the ink composition for flexible packaging lamination according to any one of [1] to [3].

[0013] [5] The flexible packaging laminating ink composition according to any one of [1] to [4], further containing a resin (C) having a glass transition temperature (Tg) of 40°C or higher.

[0014] [6] The urethane bond concentration of the urethane resin (B) is 0.6 mmol / g or more, the ink composition for laminating flexible packaging according to any one of [1] to [5].

[0015] [7] The liquid ink composition according to any one of [1] to [6], wherein the urethane resin (B) contains a biomass-derived component.

[0016] [8] The liquid ink composition according to any one of [1] to [7], wherein the proportion of biomass-derived components in the polyester polyol (b2) contained in the reaction raw material (II) in the urethane resin (B) is 30% by mass or more.

[0017] The flexible packaging laminating ink composition according to any one of [9], [1], to [8], wherein the ratio of urethane resin (A) to the total resin solids is in the range of 1 to 20% by mass.

[0018] The flexible packaging laminating ink composition according to any one of [1] to [9], wherein the ratio of urethane resin (B) to the total resin solids is in the range of 10% by mass to 80% by mass.

[0019] A printed article obtained by printing an ink composition for flexible packaging lamination described in any of [1] to

[11] onto a substrate.

[0020]

[12] A laminate or packaging containing the printed material described in

[11] .

[0021] According to this disclosure, it is possible to provide an ink composition for flexible packaging lamination that can form an ink layer with excellent fluidity, adhesion, blocking resistance, PEEL strength, dry lamination strength, boil resistance, and retort resistance.

[0022] The embodiments of the present invention (hereinafter referred to as "these embodiments") will be described in detail below, but the present invention is not limited to the following description and can be implemented in various ways within the scope of its gist. Furthermore, in these embodiments, A (numerical value) to B (numerical value) means A or greater and B or less.

[0023] [Definitions] In this specification, "ink composition" refers to a liquid printing ink applied to a printing method using a printing plate, such as gravure ink or flexographic ink, and is preferably gravure ink or flexographic ink. In the following description, "ink" always refers to "printing ink". In this specification, "parts" always refers to "parts by mass", "total ink" refers to the total amount of ink including all volatile components such as solvents, and "(ink or resin) solids (total)" refers to the total amount of non-volatile components only, excluding volatile components. In this specification, "reaction raw material" refers to a compound used to obtain a target compound by a chemical reaction such as combination or decomposition, and which partially constitutes the chemical structure of the target compound, excluding catalysts and solvents. In particular in this specification, "reaction raw material" refers to a precursor for obtaining the target urethane resin (A) or urethane resin (B) by a chemical reaction. In this specification, "constituent unit" refers to a (repeating) unit of a chemical structure formed during a reaction or polymerization. In other words, in a compound formed during a reaction or polymerization, it refers to a substructure other than the chemical bond structure involved in the reaction or polymerization, and is commonly known as a residue.

[0024] In this specification, the "aromatic group" may be substituted or unsubstituted. The "aromatic group" preferably has an aromatic ring with 3 to 30 carbon atoms, and more preferably has an aromatic ring with 4 to 26 carbon atoms, excluding the number of carbon atoms of the substituent. Furthermore, in this specification, the hydrogen atoms of the aromatic ring in the "aromatic group" may be substituted with substituents, such as alkyl groups with 1 to 10 carbon atoms, alkoxy groups with 1 to 10 carbon atoms, or halogen atoms. The "aromatic group" may also include heteroaromatic compounds, and the "-CH" in the "aromatic group" is preferable. ２The - or -CH= may be substituted with -O-, -S-, or -N= so that they are not adjacent to each other. Examples of the aromatic rings include monocyclic aromatic rings, fused aromatic rings, and ring-aggregated aromatic rings. Examples of monocyclic aromatic rings include benzene, furan, pyrrole, thiophene, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, pyridine, pyrimidine, pyridazine, pyrazine, and triazine. Examples of fused aromatic rings include naphthalene, anthracene, phenalene, phenanthrene, quinoline, isoquinoline, quinazoline, phthalazine, pteridine, coumarin, indole, benzimidazole, benzofuran, and acridine. Examples of ring-aggregated aromatic rings include biphenyl, binaphthalene, bipyridine, bithiophene, phenylpyridine, phenylthiophene, terphenyl, diphenylthiophene, and quaterphenyl. Furthermore, the hydrogen atoms of the aromatic ring in the aromatic group may be substituted with, for example, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom. A divalent aromatic group refers to an aromatic group from which two hydrogen atoms have been removed. Examples of "aryl groups" in this specification include phenyl groups, naphthyl groups, phenalenyl groups, phenantrenyl groups, anthryl groups, azulenyl groups, indenyl groups, indanyl groups, tetralinyl groups, etc. Furthermore, the hydrogen atoms of the aromatic ring in the aryl group may be substituted with, for example, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a halogen atom. An "arylene group" is a divalent group obtained by removing one arbitrary hydrogen atom from the "aryl group" mentioned above. Examples of "aralkyl groups" in this specification include benzyl groups, diphenylmethyl groups, biphenyl groups, naphthylmethyl groups, etc. The hydrogen atoms of the aromatic ring in the aralkyl group may be substituted with, for example, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or a halogen atom. The "aralkylene group" is a divalent group obtained by removing one arbitrary hydrogen atom from the "aralkyl group."In this specification, "aryloxy group" refers to phenoxy group, naphthyloxy group, anthryloxy group, phenanthryloxy group, or pyrenyloxy group, etc. The hydrogen atoms of the aromatic ring in the aryloxy group may be substituted with, for example, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a halogen atom. In this specification, "arylthio group" refers to arylthio groups such as phenylthio group, naphthylthio group, anthrylthio group, phenanthrylthio group, or pyrenylthio group. The hydrogen atoms of the aromatic ring in the arylthio group may be substituted with, for example, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a halogen atom. In this specification, "alkyl group" may be linear, branched, or cyclic, and examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, tert-pentyl group, neopentyl group, 1,2-dimethylpropyl group, n-hexyl group, isohexyl group, (n-)heptyl group, (n-)octyl group, (n-)nonyl group, (n-)decyl group, (n-)undecyl group, (n-)dodecyl group, or cycloalkyl groups as described below. An "alkylene group" is a group obtained by removing one hydrogen atom at any position from the above alkyl group, and examples include methylene group, ethylene group, propylene group, isopropylene group, n-butylene group, isobutylene group, sec-butylene group, tert-butylene group, n-pentylene group, isopentylene group, tert-pentylene group, neopentylene group, 1,2-dimethylpropylene group, n-hexylene group, isohexylene group, (n-)heptylene group, (n-)octylene group, (n-)nonylene group, (n-)decylene group, (n-)undecylene group, (n-)dodecylene group, or the cycloalkylene group described below. In this specification, "cycloalkyl group" refers to a cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, norbornyl group, or adamantyl group, etc.Examples of a "cycloalkylene group" include a group obtained by removing one hydrogen atom at any position from the cycloalkyl group, such as a cyclopropylene group, cyclobutylene group, cyclopentylene group, cyclohexylene group, cycloheptylene group, cyclooctylene group, cyclononylene group, cyclodecylene group, norbornylene group, or adamantylene group. The hydrogen atom of the cyclic group in the cycloalkyl group or the cycloalkylene group may be substituted with, for example, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a halogen atom. Examples of an "alkylthio group" in this specification include a methylthio group, an ethylthio group, a propylthio group, a butylthio group, an octylthio group, or a 2-ethylhexylthio group. In this specification, "alkenyl group" refers to groups such as ethynyl, 1-propynyl, 2-propynyl, 2-butynyl, pentynyl, hexynyl, vinyl, allyl, or isopropenyl. "Alkenylene group" refers to a group obtained by removing one hydrogen atom from the aforementioned alkenyl group. In this specification, "alkoxy group" refers to groups such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, 2-ethylhexyloxy, octyloxy, or nonyloxy. "Alkylene oxide group" refers to divalent groups such as ethylene oxide, propylene oxide, butylene oxide, and pentylene oxide. In this specification, "halogen atom" refers to groups such as fluorine, chlorine, bromine, or iodine. "Organic group" refers to a group having 1 to 20 carbon atoms. Therefore, the above-mentioned "aromatic groups," "aryl groups," "arylene groups," "aralkyl groups," "aralkylene groups," "aryloxy groups," "arylthio groups," "alkyl groups," "cycloalkyl groups," "alkylthio groups," "alkenyl groups," "alkenylene groups," "alkoxy groups," and "alkylene oxide groups" are all included in the category of "organic groups." Furthermore, any hydrogen atom can be removed according to the valency. For example, a trivalent alkyl group is a group obtained by removing two arbitrary hydrogen atoms from an alkyl group.

[0025] [Ink composition for flexible packaging lamination (hereinafter also simply referred to as ink composition)] This disclosure relates to an ink composition for flexible packaging lamination that essentially contains a urethane resin (A) having a number average molecular weight of 1,000 to 3,000. The urethane resin (A) is a compound using an organic diisocyanate compound (a1) and a polyol (a2) having a number average molecular weight (Mn) of 700 to 900 as reaction raw materials (I). This allows for the formation of an ink layer with excellent adhesion, blocking resistance, PEEL strength, and dry lamination strength. The ink composition for flexible packaging lamination of this embodiment further includes a urethane resin (B) using at least an aromatic polyisocyanate compound (b1) and a polyester polyol (b2) as reaction raw materials (II). This allows for the formation of an ink layer with even better adhesion, blocking resistance, PEEL strength, dry lamination strength, boil resistance, and retort resistance. The ink composition for flexible packaging lamination according to this embodiment may further contain urethane resins other than urethane resin (A) and urethane resin (B). This allows for the formation of an ink layer with superior adhesion, blocking resistance, PEEL strength, and dry lamination strength.

[0026] Furthermore, the flexible packaging lamination ink composition of this embodiment may further contain a resin (C) having a glass transition temperature (Tg) of 40°C or higher, if necessary. The resin (C) having a glass transition temperature (Tg) of 40°C or higher is preferably one or more selected from the group consisting of polyvinyl butyral resins, cellulose resins (e.g., cellulose acetate propionate, cellulose acetate butyrate), and vinyl chloride-vinyl acetate copolymer resins, as described later. For example, by selecting a polyvinyl butyral resin and / or a cellulose resin as the resin (C) having a glass transition temperature (Tg) of 40°C or higher, the effect of reducing environmental impact can be further enhanced. The flexible packaging lamination ink composition of this embodiment may further contain one or more selected from the group consisting of other resins, pigments, organic solvents, and additives, if necessary.

[0027] The following describes in detail the essential components of the flexible packaging laminating ink composition of this disclosure, namely urethane resin (A) and urethane resin (B), as well as the optional components, namely resin (C) having a glass transition temperature (Tg) of 40°C or higher, other resins, pigments, organic solvents, and additives.

[0028] (Urethane resin (A)) The flexible packaging laminating ink composition of this embodiment contains a urethane resin (A) having a number average molecular weight of 1,000 to 3,000 as an essential component. The urethane resin (A) is a compound using an organic diisocyanate compound (a1) and a polyol (a2) having a number average molecular weight (Mn) of 700 to 900 as reaction raw materials (I). In other words, the urethane resin (A) in this embodiment has a structure in which constituent units derived from the organic diisocyanate compound (a1) and constituent units derived from the polyol (a2) having a number average molecular weight (Mn) of 700 to 900 are directly or indirectly chemically bonded. The urethane resin (A) has the function of improving the adhesion of the ink as a binder resin and can also function as a pigment dispersion resin. Furthermore, it is preferable that the urethane resin (A) does not have a urea bond (-NH-C(=O)-NH-). In this specification, "constituent unit" refers to a repeating unit of a chemical structure formed during a reaction or polymerization.

[0029] In the flexible packaging lamination ink composition of this embodiment, the content of urethane resin (A) is preferably 1 to 20% by mass, more preferably 3 to 18% by mass, and even more preferably 4 to 16% by mass, based on the total resin solids content of the flexible packaging lamination ink composition. By setting the content of urethane resin (A) to 1% by mass or more, good adhesion and PEEL strength are exhibited. On the other hand, by setting the content of urethane resin (A) to 20% by mass or less, good blocking resistance is exhibited.

[0030] The following describes the components of the reaction raw material (I) of the urethane resin (A) (organic diisocyanate compound (a1) and polyol (a2) with a number-average molecular weight (Mn) of 700 to 900), followed by a description of the preferred form of the urethane resin (A).

[0031] <Organic Diisocyanate Compound (a1)>The organic diisocyanate compound (a1) used in the urethane resin (A) of the present embodiment includes various known aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, etc. generally used in the production of general polyurethane resins. As the organic diisocyanate compound (a1), the following general formula (ii):

[0032] (In the above general formula (ii), L ５ and L ６ each independently represent a single bond or an alkylene group having 1 to 5 carbon atoms, and M ２ represents a divalent organic group.) is preferably represented. In the above general formula (ii), L ５ is preferably a single bond or an alkylene group having 1 to 3 carbon atoms. In the above general formula (ii), L ６ is preferably a single bond or an alkylene group having 1 to 3 carbon atoms. In the above general formula (ii), the divalent organic group preferably has 1 to 20 carbon atoms, more preferably has 2 to 18 carbon atoms, and even more preferably has 3 to 17 carbon atoms. The "organic group" refers to a group having 1 or more carbon atoms, and is preferably a hydrocarbon group having 1 to 20 carbon atoms. As the above divalent organic group, an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 1 to 20 carbon atoms, an alkyleneoxy group having 1 to 20 carbon atoms, or an arylene group having 6 to 18 carbon atoms is preferable. Further, one or two or more non-adjacent -CH ２ - in the alkylene group, alkenylene group, alkyleneoxy group or arylene group may be substituted with -O-, -COO- or -OCO-. In the above general formula (ii), M ２ is preferably an alkylene group having 3 to 12 carbon atoms, excluding the carbon atoms of the substituents.

[0033] Specific examples of the organic diisocyanate compound (a1) of this embodiment include, for example, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyli isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylenediisocyanate, 1,4-phenylenediisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropyl diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate Preferred diisocyanates include cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dimeryl diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanate-methyl)cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, m-tetramethylxylylene diisocyanate, 4,4-diphenylmethane diisocyanate, tolylene diisocyanate, bis-chloromethyl-diphenylmethane diisocyanate, 2,6-diisocyanate-benzyl chloride, and dimer diisocyanates obtained by converting the carboxyl groups of dimer acids to isocyanate groups. These diisocyanate compounds can be used individually or in combination of two or more. Among the examples of the above organic diisocyanate compounds (a1), hexamethylene diisocyanate, xylylene diisocyanate, and isophorone diisocyanate are preferred, and isophorone diisocyanate is particularly preferred.

[0034] In the reaction raw material (I) of the urethane resin (A) of this embodiment, the proportion of the organic diisocyanate compound (a1) is preferably 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 5 to 25% by mass, based on the total amount (100% by mass) of the reaction raw material (I). The content of the constituent units of the organic diisocyanate compound (a1) (constituent units derived from the organic diisocyanate compound (a1), so-called organic diisocyanate compound (a1) residues) of the organic diisocyanate compound (a1) of this embodiment is preferably in the range of 1 to 50% by mass, and more preferably 5 to 40% by mass, based on the total amount of the urethane resin (A) (resin solids). If the content of constituent units of the organic diisocyanate compound (a1) is 1 part by mass or more per 100 parts by mass of the urethane resin (A), a tough ink film and good blocking resistance can be obtained. If it is 40 parts by mass or less, a flexible ink film can be obtained.

[0035] <Polyol (a2)> The polyol (a2) of this embodiment preferably has a substructure represented by the following general formula (i).

[0036] (In the above general formula (i), D １ represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 15 carbon atoms, provided that the alkyl group contains one or more -CH groups. ２ - may be substituted with -O-, -COO-, or -OCO-, L １ and L ２ Each of these independently represents a single bond or an alkylene group having 1 to 5 carbon atoms, provided that the alkylene group contains one or more -CH groups. ２ - may be substituted with -O-, -COO-, or -OCO-, L ３ Each of these independently represents a single bond or a group represented by the following general formula (a):

[0037] (In the above general formula (a), L ４ represents a mezine group (-CH=) or a trivalent organic group, R １ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a monovalent aromatic group, while * represents M in general formula (i). １The first symbol (*) represents a chemical bond with the second symbol (*), while the second symbol (*) represents a chemical bond with the OH (hydroxyl group) in general formula (i). １ Each of these independently represents a mezine group (-CH=), a trivalent alicyclic group with 3 to 15 carbon atoms, or a trivalent aromatic group, where ni is the number of repeating units and represents an integer of 2 or more. Note that in the general formula (i) above, * represents a bond with another atom.

[0038] In this embodiment, in the above general formula (i), D １ It is preferably a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 3 carbon atoms. In the above general formula (i), L １ The alkylene group is preferably an alkylene group having 1 to 3 carbon atoms, and a methylene group is particularly preferred. However, the alkylene group contains 1 or more -CH groups. ２ - may be replaced with -O-, -COO-, or -OCO-. In the above general formula (i), L ２ The alkylene group is preferably a single bond or an alkylene group having 1 to 3 carbon atoms, with a single bond being more preferable. However, the alkylene group may contain one or more -CH groups. ２ - may be replaced with -O-, -COO-, or -OCO-. In the above general formula (i), L ３ It is preferable that L is a single bond or a group represented by the above general formula (a). ３ If L is a group represented by the above general formula (a), ４ It is preferable that it is a mezine group. And R １ It is preferably a monovalent aromatic group that is unsubstituted or has 1 to 4 hydrogen atoms substituted by a substituent, and more preferably a phenyl group, naphthyl group, phenalenyl group, phenantrenyl group, anthryl group, azlenyl group, indenyl group, indanyl group, or tetralinyl group that is unsubstituted or has 1 to 3 hydrogen atoms substituted by a substituent. The substituent is preferably an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a halogen atom. In the above general formula (i), M １It is preferable that is a mezine group or a trivalent alicyclic group having 4 to 8 carbon atoms (for example, cyclohexane-triyl which may be substituted with an alkyl group having 1 to 3 carbon atoms). In the above general formula (i), the trivalent organic group can be a group obtained by removing one arbitrary hydrogen atom from the above examples of "divalent organic groups". In the above general formula (i), ni is preferably an integer between 2 and 1000, preferably an integer between 2 and 100, preferably an integer between 2 and 10, and more preferably between 2 and 8.

[0039] The polyol (a2) of this embodiment preferably has an aromatic ring, and more preferably has an aromatic ring in the general formula (i). The presence of an aromatic ring in the polyol (a2) makes it easier to exhibit effects such as improved pigment dispersibility, PEEL strength, and dry laminate strength. Another preferred polyol (a2) is a polyol having an alkylene oxide skeleton, such as polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. The preferred embodiment of the polyol (a2) of this embodiment is that the polyol (a2) has a substructure represented by the general formula (i), and L in the general formula (i) ３ The group is represented by the above general formula (a), and R １ This represents a monovalent aromatic group. In other words, the polyol (a2) of this embodiment preferably has a substructure represented by the following general formula (i-1).

[0040] (In the above general formula (i-1), D １ represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 15 carbon atoms, provided that the alkyl group contains one or more -CH groups. ２ - may be substituted with -O-, -COO-, or -OCO-, L １ and L ２ Each of these independently represents a single bond or an alkylene group with 1 to 5 carbon atoms, L ４ Each of these independently represents a mezine group (-CH=), and R １’ Each of these independently represents a monovalent aromatic group, M １Each of these independently represents a mezine group (-CH=), a trivalent alicyclic group with 3 to 15 carbon atoms, or a trivalent aromatic group, where ni is the number of repeating units and represents an integer of 2 or more. Note that in the general formula (i-1) above, * represents a bond with another atom.

[0041] In the above general formula (i-1), R １’ It is preferable that the group is unsubstituted or has one to three hydrogen atoms substituted by substituents, and is a phenyl group, naphthyl group, phenalenyl group, phenantrenyl group, anthryl group, azlenyl group, or indenyl group. The other symbols of general formula (i-1) are the same as those of general formula (i).

[0042] A particularly preferred embodiment of the polyol (a2) in this embodiment is that it has a substructure represented by the following general formula (i-1.1).

[0043] (In the above general formula (i-1.1), D １ represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 15 carbon atoms, provided that the alkyl group contains one or more -CH groups. ２ The - can be replaced with -O-, -COO-, or -OCO-, R ２ Each of these can be independently unsubstituted or substituted R ３ The substituent R represents a phenyl group, naphthyl group, or phenalenyl group, which may be substituted with 1 to 5 hydrogen atoms. ３ D represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a halogen atom, and ni is the number of repeating units, representing an integer of 2 or more. Note that * in the above general formula (i-1.1) represents a bond with another atom.) In the above general formula (i-1.1), D １ R is preferably a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 8 carbon atoms. In the above general formula (i-1.1), ２ Each of these can be independently unsubstituted or substituted R ５ The substituent R represents a phenyl group or a naphthyl group, which may be substituted with 1 to 3 hydrogen atoms. ５This represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or a halogen atom.

[0044] The number-average molecular weight (Mn) of the polyol (a2) in this embodiment is 700 to 900. A number-average molecular weight (Mn) of 700 to 900 for the polyol (a2) is preferable from the viewpoint of balancing adhesion to the film and blocking resistance. If the number-average molecular weight of the polyol (a2) is too low, the cured urethane resin film tends to become hard, reducing its adhesion to the film. On the other hand, if the number-average molecular weight is too high, the cured urethane resin film tends to become brittle, reducing the blocking resistance of the ink film. In this specification, the number-average molecular weight and weight-average molecular weight are values ​​measured by gel permeation chromatography (GPC) under the following conditions.

[0045] Measurement device: High-speed GPC instrument (HLC-8220GPC manufactured by Tosoh Corporation) Column: The following columns manufactured by Tosoh Corporation were used in series: "TSKgel G5000" (7.8 mm I.D. × 30 cm) × 1 "TSKgel G4000" (7.8 mm I.D. × 30 cm) × 1 "TSKgel G3000" (7.8 mm I.D. × 30 cm) × 1 "TSKgel G2000" (7.8 mm I.D. × 30 cm) × 1 Detector: RI (differential refractometer) Column temperature: 40°C Eluent: Tetrahydrofuran (THF) Flow rate: 1.0 mL / min Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4 mass%) Standard samples: Calibration curves were prepared using the following standard polystyrene.

[0046] [Standard Polystyrene] TSKgel Standard Polystyrene A-500 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene A-1000 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene A-2500 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene A-5000 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-1 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-2 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-4 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-10 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-20 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-40 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-80 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-128 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-288 (manufactured by Tosoh Corporation) TSKgel Standard Polystyrene F-550 (manufactured by Tosoh Corporation)

[0047] The hydroxyl value of the polyol (a2) in this embodiment is preferably 80 to 450 mg KOH / g, more preferably 100 to 400 mg KOH / g, and even more preferably 105 to 385 mg KOH / g. When the hydroxyl value of the polyol (a2) is within the above range, it is easier to control the urethane bond concentration to a predetermined value or higher, which can further improve the laminate strength.

[0048] In the reaction raw material (I) of the urethane resin (A) of this embodiment, the proportion of the polyol (a2) is preferably 60% to 99% by mass, and more preferably 65% ​​to 95% by mass, relative to the total amount (100% by mass) of the reaction raw material (I). That is, it is preferable that the polyol structure of the urethane resin (A) has constituent units derived from polyol (a2), as this improves the lamination strength. Furthermore, it is preferable that the urethane resin (A) further contains constituent units derived from polyol, which can be used in combination as needed, as this improves the dispersibility and fluidity of the ink and also improves adhesion. In this embodiment, the content of the constituent units of polyol (a2) (constituent units derived from polyol (a2), so-called polyol (a2) residues) is preferably in the range of 60% to 99% by mass, and more preferably 65% ​​to 95% by mass, relative to the total amount of urethane resin (A) (resin solids). When the content of polyol (a2) constituent units is 60% by mass or more per 100 parts by mass of urethane resin (A), the solubility of the urethane resin (A) in ketone, ester, and alcohol-based solvents is ensured, resulting in good adhesion on a high-performance barrier film. Furthermore, the resolubility of the ink film in the solvent is improved, enhancing the tonal reproduction of printed materials. If the content is 99% by mass or less, the ink film has appropriate flexibility, which tends to result in good blocking resistance.

[0049] (Preferred embodiment of urethane resin (A)) The urethane resin (A) of this embodiment has a number average molecular weight (Mn) of 1,000 to 3,000, preferably 1,200 to 3,000. A number average molecular weight (Mn) of urethane resin (A) of 1,000 to 3,000 is preferable in terms of the blocking resistance of the ink composition, the strength and oil resistance of the printed film, and the gloss of the printed film. The urethane resin (A) of this embodiment has the following general formula (I):

[0050] (In the above general formula (I), R ３ and R ４Each of the above general formulas (I) independently represents an aromatic group having 6 to 15 carbon atoms, and M represents a divalent organic group, preferably an aliphatic hydrocarbon group (alkylene group or alkenylene group) having 1 to 20 carbon atoms. In the above general formula (I), * represents a bond with another atom. It is preferable to have a substructure represented by the above general formula (I). By having a substructure represented by the above general formula (I), the urethane resin (A) can form an ink layer with superior adhesion, blocking resistance, PEEL strength, and dry lamination strength. In the above general formula (I), R ３ and R ４ Each of these independently has 1 to 3 hydrogen atoms that are either unsubstituted or substituted with a substituent R. ５ The substituent R preferably represents a phenyl group or a naphthyl group, which may be substituted by the substituent R. ５ represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or a halogen atom. In the above general formula (I), M is preferably an alkylene group having 3 to 12 carbon atoms, without including the number of carbon atoms of the substituent.

[0051] (Properties of Urethane Resin (A)) The urethane bond concentration of the urethane resin (A) in this embodiment is preferably 0.9 mmol / g or more, more preferably 1.0 mmol / g or more and 3.0 mmol / g or less, and even more preferably in the range of 1.1 mmol / g or more and 2.6 mmol / g or less. When the urethane bond concentration is 1.1 mmol / g or more, the laminate strength is particularly excellent. The urethane bond concentration can be calculated by the following formula (1). [Formula (1)]: Urethane bond concentration = {(W １ ×OH １ +W ２ ×OH ２ +...+W ｉ ×OH ｉ ) × 1000} / (56100 × S) In the above formula (1), each is as follows: W １ : Weight of polyol (a2-1) OH １ : Hydroxyl value of polyol (a2-1) W ２ : Weight of polyol (a2-2) OH ２: Hydroxyl value of polyol (a2-2) Wi: Weight of polyol (a2-i) OHi: Hydroxyl value of polyol (a2-i) S １ : Weight of solids in urethane resin (A) Note that in the above formula (1), polyol (a2-1), polyol (a2-2), polyol (a2-3)...polyol (a2-i) are all included in polyol (a2) with a number average molecular weight (Mn) of 700 to 900. That is, when i types of polyol (a2) are used as reaction raw materials (I) for urethane resin (A), the numerator of the above formula (1) is the sum of the amount of each of the i types of polyol (a2) and the hydroxyl value of each polyol (a2). The denominator of the above formula (1) is S, which is the weight of solids in the obtained urethane resin (A). １ This value is obtained by multiplying by 56100.

[0052] The urethane resin (A) of this embodiment may consist only of a resin having a substructure represented by general formula (I), or it may be a mixture containing a resin having a substructure represented by general formula (I). In this embodiment, the lower limit of the content of the resin having a substructure represented by general formula (I) relative to the total urethane resin (A) (resin solids) (100% by mass) is preferably 10% by mass or more, 20% by mass or more, 30% by mass or more, 32% by mass or more, 34% by mass or more, or 36% by mass or more. On the other hand, the upper limit of the content of the resin having a substructure represented by general formula (I) is preferably 100% by mass or less, 95% by mass or less, 90% by mass or less, 80% by mass or less, 78% by mass or less, or 74% by mass or less. The preferred range for the content of the urethane resin (A) having a substructure represented by general formula (I) is, in order of preference, 10% to 100% by mass, 20% to 95% by mass, 30% to 90% by mass, and 32% to 80% by mass, relative to the total urethane resin (A) (resin solids) (100% by mass). When the content of the resin having a substructure represented by general formula (I) is between 10% by mass and 100% by mass, a tough ink film, good adhesion, and PEEL strength can be obtained. The above upper and lower limits can be combined as appropriate. In this embodiment, the lower limit of the content of the resin having a substructure represented by general formula (I) relative to the total resin solids (100% by mass) of the ink composition is preferably 1% by mass or more, 3% by mass or more, 5% by mass or more, 8% by mass or more, 12% by mass or more, or 15% by mass or more. On the other hand, the upper limit of the content of the resin having a substructure represented by general formula (I) is preferably 100% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 64% by mass or less, or 61% by mass or less. The range of the content of the urethane resin (A) having a substructure represented by general formula (I) is preferably 1% by mass to 100% by mass, 5% by mass to 80% by mass, and 12% by mass to 64% by mass, in that order, relative to the total resin solids content (100% by mass) of the ink composition. The above upper and lower limits can be combined as appropriate.

[0053] (Urethane resin (B)) The flexible packaging lamination ink composition of this embodiment may contain a urethane resin (B) whose reaction raw material (II) is at least an aromatic polyisocyanate compound (b1) and a polyester polyol (b2). The urethane resin (B) preferably has a urea bond. This provides good boil resistance, retort resistance, and blocking resistance. The urethane resin (B) has a different chemical structure from the urethane resin (A), and it is preferable that the urethane resin (A) does not have a urea bond. By containing both the urethane resin (A) and the urethane resin (B) having a different chemical structure from the urethane resin (A), the flexible packaging lamination ink composition of this embodiment can have the function of further improving the adhesion of the ink as a binder resin and can also exhibit a better function as a pigment dispersion resin. The urethane resin (B) of this embodiment is a compound whose reaction raw material (II) is an aromatic polyisocyanate compound (b1) and a polyol component (for example, including at least a polyester polyol (b2)). In other words, the urethane resin (B) in this embodiment has a structure in which constituent units derived from an aromatic polyisocyanate compound (b1) and constituent units derived from a polyester polyol (b2) are chemically bonded directly or indirectly. As will be described later, the urethane resin (B) may also use polyester polyol (b2) and polyether polyol (b3) as reaction raw materials (II) as the polyol components. That is, a preferred urethane resin (B) in this embodiment may be a compound in which aromatic polyisocyanate compound (b1), polyester polyol (b2), and polyether polyol (b3) are used as reaction raw materials (II). For convenience, in this specification, the reaction raw materials of urethane resin (B) are referred to as reaction raw materials (II), and the reaction raw materials of urethane resin (A) are referred to as reaction raw materials (I) to distinguish between the two.

[0054] In the flexible packaging lamination ink composition of this embodiment, the content of urethane resin (B) is preferably 10% to 80% by mass, more preferably 15% to 78% by mass, even more preferably 18% to 75% by mass, and even more preferably 20% to 75% by mass, based on the total resin solids content (100% by mass) of the flexible packaging lamination ink composition. By setting the content of urethane resin (B) to 10% by mass or more, good resistance to boiling, retort, and blocking is exhibited. On the other hand, by setting the content of urethane resin (B) to 80% by mass or less, appropriate ink viscosity and good printability are exhibited. Note that urethane resin (B) refers to a resin other than urethane resin (A) that uses an aromatic polyisocyanate compound (b1) and polyester polyol (b2) as reaction raw materials (II).

[0055] <Polyisocyanate compound (b1)> The reaction raw material (II) of the urethane resin (B) in this embodiment contains an aromatic polyisocyanate compound (b1). The aromatic polyisocyanate compound (b1) used in the urethane resin (B) in the ink composition of this embodiment is preferably a compound having two or more isocyanate groups, and more preferably a diisocyanate compound. The aromatic polyisocyanate compound (b1) is preferably one of the various known aromatic polyisocyanates commonly used in the production of the above-mentioned known polyurethane resins. Examples include 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, xylylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, m-tetramethylxylylene diisocyanate, and dimer isocyanate obtained by converting the carboxyl groups of dimer acid to isocyanate groups. These aromatic polyisocyanate compounds can be used alone or in combination of two or more. By using the aromatic polyisocyanate compound (b1) as a reaction raw material, the ink film can be made tougher, and its adhesion, blocking resistance, PEEL strength, dry lamination strength, boil resistance, and retort resistance can be further improved. The reaction raw material (II) for the urethane resin (B) may be an aromatic polyisocyanate compound (b1) and one or more polyisocyanate compounds other than the aromatic polyisocyanate compound (b1) in combination.Other polyisocyanate compounds besides aromatic polyisocyanate compound (b1) include various known aromatic polyisocyanates commonly used in the production of the above-mentioned known polyurethane resins, such as butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropyl diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dimeryl diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanate-methyl)cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, and the like.

[0056] In the reaction raw material (II) of the urethane resin (B) of this embodiment, the proportion of the aromatic polyisocyanate compound (b1) is preferably 1% to 40% by mass, and more preferably 5% to 30% by mass, based on the total amount (100% by mass) of the reaction raw material (II). Furthermore, the content of constituent units of the aromatic polyisocyanate compound (b1) in the urethane resin (B) is preferably in the range of 1% to 40% by mass, and more preferably in the range of 5% to 30% by mass, relative to the urethane resin (B). If the aromatic polyisocyanate compound (b1) is 1% by mass or more, a tough ink film can be obtained. If it is 40% by mass or less, a flexible ink film can be obtained.

[0057] <Polyester Polyol (b2)> The reaction raw material (II) of the urethane resin (B) of this embodiment contains at least polyester polyol (b2). That is, polyester polyol (b2) is essential as the polyol component of the urethane resin (B). Therefore, if necessary, the reaction raw material (II) may further contain polyether polyol (b3) and / or a polyol used in combination. In one embodiment of the urethane resin (B) of this embodiment, when polyester polyol (b2) and polyether polyol (b3) are part of the reaction raw material (II), it is preferable that the mass ratio of polyester polyol (b2) is large in the total mass of polyester polyol (b2) and polyether polyol (b3). In the reaction raw material (II) of the urethane resin (B) of this embodiment, the total proportion of polyester polyol (b2) and polyether polyol (b3) is preferably 40% to 99% by mass, and more preferably 50% to 95% by mass, relative to the total amount (100% by mass) of the reaction raw material (II). In the reaction raw material (II) of the urethane resin (B) of this embodiment, the proportion of the polyester polyol (b2) is preferably 40% to 95% by mass, and more preferably 50% to 95% by mass, relative to the total amount (100% by mass) of the reaction raw material (II). That is, it is preferable that the polyol structure of the urethane resin (B) has constituent units derived from polyester polyol (b2), as this improves the lamination strength. Furthermore, it is preferable that it also has constituent units derived from polyether polyol (b3), as this improves the dispersibility and fluidity of the ink, and also improves adhesion.

[0058] In this embodiment, the mass ratio ((b2):(b3)) of polyester polyol (b2) and polyether polyol (b3) in the polyol structure (a structure having two or more hydroxyl groups) is preferably in the range of 45:55 to 100:0, more preferably in the range of 50:50 to 100:0, and even more preferably in the range of 55:45 to 99:1. If the mass ratio of polyester polyol (b2) and polyether polyol (b3) is in the range of 45:55 to 100:0, it is preferable to obtain printed materials that are less prone to blocking. If the mass ratio is in the range of 55:45 to 99:1, it is preferable to obtain an ink that is particularly excellent in lamination strength, adhesion, and ink dispersibility. Furthermore, in the flexible packaging laminating ink composition of this embodiment, when polyvinyl butyral resin is used in combination, if the mass ratio of the polyester polyol (b2) and polyether polyol (b3) is within the range of 55:45 to 99:1, good compatibility can be obtained, resulting in suitable storage stability and fluidity.

[0059] The polyester polyol (b2) in this embodiment is preferably a compound obtained by dehydration condensation or polymerization of a low molecular weight polyol and a polycarboxylic acid or an anhydride thereof. The lamination strength of the polyester polyol (b2) can be further increased by introducing ester groups to increase the cohesive energy.

[0060] As the low molecular weight polyol mentioned above, various known compounds having two or more hydroxyl groups that are commonly used in the production of known polyester polyols can be used. For example, one or more compounds may be used in combination as the polyester polyol (b2). Specifically, as the low molecular weight polyol, for example, glycols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol; 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2-butanediol, 1,3-butanediol, 2-butyl-2- Branched glycols such as ethyl-1,3-propanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 2-isopropyl-1,4-butanediol, 2,4-dimethyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,6-hexanediol, 3,5-heptanediol, and 2-methyl-1,8-octanediol can be used; glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, etc. can also be used.

[0061] As the polycarboxylic acid or its anhydride, various known polycarboxylic acids commonly used in the production of known polyester polyols can be used. In addition, one or more compounds may be used in combination as the polycarboxylic acid or its anhydride. Specifically, for example, polycarboxylic acids having 6 or fewer carbon atoms and 2 or more carboxyl groups, such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid and anhydrides of these acids; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid and anhydrides of these acids; aliphatic dicarboxylic acids such as pimelic acid, suberic acid, azelaic acid, sebacic acid, and dimer acid; tricarboxylic acids such as trimellitic acid and its anhydride; benzenetetracarboxylic acid, benzenepentacarboxylic acid, benzenehexacarboxylic acid and anhydrides of these acids can be used.

[0062] Furthermore, the polyester polyol (b2) may be any known polyester polyol commonly used in the production of polyurethane resins, such as cyclic ester compounds, including polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, polyvalerolactone, and poly(β-methyl-γ-valerolactone), or one or more compounds may be used in combination.

[0063] The number average molecular weight of the polyester polyol (b2) is preferably in the range of 500 to 8,000, more preferably in the range of 800 to 7,000, even more preferably in the range of 900 to 6,000, and still more preferably in the range of over 900 and 6,000 or less.

[0064] The content of the constituent units of polyester polyol (b2) is preferably in the range of 40% to 85% by mass, more preferably in the range of 50% to 80% by mass, relative to the urethane resin (B). When the polyester polyol (b2) is 40 parts by mass or more per 100 parts by mass of urethane resin (B), the solubility of the urethane resin (B) in ketone, ester, and alcohol-based solvents is ensured, and adhesion on the high-performance barrier film is good. Furthermore, the resolubility of the ink film in the solvent is good, improving the tone reproduction of printed materials. When the amount is 85 parts by mass or less, the ink film has appropriate flexibility, which tends to result in good blocking resistance.

[0065] <Polyether polyol (b3)> The urethane resin (B) of this embodiment may contain polyether polyol (b3) as a reaction raw material (II). As the polyether polyol (b3), which is an optional component of the reaction raw material (II), various polyether polyols commonly used in the production of known polyurethane resins can be used, and one or more types may be used in combination. For example, polyether polyols of polymers or copolymers of methylene oxide, ethylene oxide, propylene oxide, tetrahydrofuran, etc. Specifically, known and commonly used ones such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol may be used. By including polyether polyol, adhesion, especially on high-performance barrier films, is greatly improved, resulting in superior blocking resistance and lamination strength.

[0066] The polyether polyol (b3) preferably has a number average molecular weight of 100 to 3500. If the number average molecular weight of the polyether polyol is less than 100, the polyurethane resin film tends to harden, reducing its adhesion to the polyester film. If the number average molecular weight is greater than 3500, the resulting resin film tends to be brittle, reducing the blocking resistance of the ink film.

[0067] In the reaction raw material (II) of the urethane resin (B) of this embodiment, the proportion of the polyester polyol (b2) is preferably 40% to 95% by mass, and more preferably 50% to 95% by mass, relative to the total amount (100% by mass) of the reaction raw material (II). When the reaction raw material (II) contains polyether polyol (b3), the constituent units of the polyether polyol (b3) are preferably contained in an amount of 1% to 40% by mass relative to the urethane resin (B). If the polyether polyol is 1 part by mass or more per 100 parts by mass of urethane resin (B), the solubility of the urethane resin (B) in ketone, ester, and alcohol-based solvents is ensured, and adhesion on the high-performance barrier film is good. Furthermore, the resolubility of the ink film in the solvent is good, and the tone reproducibility of the printed material is improved. If it is 40 parts by mass or less, the ink film has appropriate flexibility, so it tends to have good blocking resistance.

[0068] The reaction raw material (I) of the urethane resin (A) and / or the reaction raw material (II) of the urethane resin (B) in this embodiment may further contain a combined polyol as needed. As the combined polyol used as needed in the urethane resin (A) and / or (B) used in the flexible packaging laminating ink composition of this embodiment, various known polyols commonly used in the production of polyurethane resins can be used, and one or more types may be used in combination. For example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaestritol, etc. Examples include saturated or unsaturated low molecular weight polyols (1); polycarbonate polyols obtained by reacting the low molecular weight polyols with, for example, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, etc. (2); polybutadiene glycols (3); glycols obtained by adding ethylene oxide or propylene oxide to bisphenol A (4); and acrylic polyols obtained by copolymerizing one or more hydroxyethyl acrylates, hydroxypropyl acrylates, hydroxybutyl acrylates, etc., or their corresponding methacrylic acid derivatives, etc., with, for example, acrylic acid, methacrylic acid, or their esters (4).

[0069] Furthermore, if the combined polyols mentioned above include polyester polyol (b2) and / or polyether polyol (b3), the content of polyester polyol (b2) and / or polyether polyol (b3) contained in the combined polyols is also included in the mass of polyester polyol (b2) and / or polyether polyol (b3) in the polyol structure of urethane resin (B), respectively. In addition, the reaction raw material (II) of urethane resin (B) may contain amine compounds such as chain extenders. Examples of the amine compounds include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, as well as amines having hydroxyl groups in their molecules, such as 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyropyrethylenediamine, di-2-hydroxypyropyrethylenediamine, cyclohexylamine, di-2-hydroxypropylethylenediamine, and di-n-butylamine, among other dialkylamines. By including the above amine compounds in the reaction raw material (II) of the urethane resin (B), it becomes easier to introduce urea bonds into the urethane resin (B). Furthermore, because the urea bonds in the urethane resin (B) have a low degree of rotational freedom due to their molecular structure, it becomes easier to ensure high rigidity of the entire composition. Therefore, the urethane resin (B) of this embodiment, having both urethane bonds and urea bonds, is more likely to have improved rigidity and elongation performance.

[0070] In the urethane resin (B) of this embodiment, it is preferable that the reaction raw material (II) contains a biomass-derived raw material. The urethane resin (B) of this embodiment is a compound in which a polyisocyanate compound (b1) and at least a polyester polyol (b2) and optionally a polyether polyol (b3) are used as reaction raw materials (II), but the biomass in the reaction raw material (II) can be any material. Preferably, at least one component or raw material constituting the polyester polyol (b2) and / or polyether polyol (b3) is biomass. More specifically, "at least one raw material constituting the polyester polyol (b2) is biomass" means that at least a portion of the total carbon atoms constituting the polyester polyol (b2) include carbon atoms derived from biomass. Furthermore, if the polyester polyol (b2) is a compound obtained by dehydration condensation or polymerization of a low molecular weight polyol and a polycarboxylic acid or its anhydride, then the low molecular weight polyol and / or polycarboxylic acid or its anhydride is considered biomass (in other words, the total carbon atoms in the low molecular weight polyol and / or polycarboxylic acid or its anhydride contain carbon atoms derived from biomass). Similarly, if at least one component or raw material constituting the polyether polyol (b3) is biomass, then at least a portion of the total carbon atoms constituting the polyether polyol (b3) contains carbon atoms derived from biomass. Note that biomass refers to organic resources produced from plants and animals that can be recycled into energy or matter (for example, agricultural, forestry, and fishery products or parts thereof, rice straw, rice husks, food waste, livestock excrement, or wood chips, etc.), excluding fossil fuels such as petroleum and coal. For example, when the polyester polyol (b2) is composed of biomass, it is preferable that the polycarboxylic acid or its anhydride, which is the raw material for the polyester polyol (b2), contains carbon atoms derived from biomass.Examples of polycarboxylic acids containing carbon atoms derived from biomass include adipic acid (e.g., adipic acid obtained using microorganisms, see International Publication No. 2012 / 137771), azelaic acid (e.g., azelaic acid obtained by ozonolysis of oleic acid isolated from olive oil), sebacic acid (e.g., sebacic acid obtained by alkali treatment of ricinoleic acid obtained from castor oil at high temperature, see Japanese Patent Publication No. 2001-511809), dodecanedicarboxylic acid, maleic anhydride (e.g., maleic anhydride obtained by the method of International Publication No. 2016 / 198744), fumaric acid (e.g., Biomass-derived raw materials can include fumaric acid obtained from the cob of sorghum (e.g., see International Publication No. 2011 / 059013), succinic acid (obtained by hydrogenating the fumaric acid), 1,4-butanediol (obtained by hydrogenating the fumaric acid), 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, phthalic acid (e.g., obtained by the method described in International Publication No. 2014 / 043468 or Japanese Patent Publication No. 2019-507757), and anhydrides of these acids. These polybasic acids may be used individually or in combination of two or more. In addition, various biomass-derived alcohols known as low molecular weight polyols may be used. Furthermore, the polyether polyol (b3) itself or its raw materials may be biomass, such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc. To obtain a more environmentally friendly ink, it is desirable that the proportion of biomass in the urethane resin (B) be high. For example, when biomass is used as the polyester polyol (b3) of the reaction raw material (II) in the urethane resin (B), it is preferable that the proportion of biomass-derived solid components in the polyester polyol (b3) be 30% by mass or more, preferably 40% by mass or more, and more preferably 50% by mass or more.For example, if the polyester polyol (b3) is a compound obtained by dehydration condensation or polymerization using a biomass low molecular weight polyol and / or a biomass polycarboxylic acid or anhydride thereof, the total content (solid component) of biomass low molecular weight polyol residues and biomass polycarboxylic acid or anhydride residues in the polyester polyol (b3) is preferably 30% by mass or more, preferably 40% by mass or more, and more preferably 50% by mass or more. The proportion of biomass-derived solid components in the polyester polyol (b3) can be calculated from the amount used.

[0071] The lower limit of the biomass carbon content (%) of the urethane resin (B) (solids) in this embodiment is preferably 30% or more, 33% or more, 35% or more, 37% or more, 40% or more, 45% or more, 48% or more, and 50% or more, in that order. On the other hand, the upper limit of the biomass carbon content (%) is preferably 100% or less, 90% or less, 80% or less, 73% or less, and 68% or less, in that order. These upper and lower limits can be combined arbitrarily. For example, the preferred range of biomass carbon content (%) for the urethane resin (B) (solids) is preferably 30% or more, more preferably 30% or more and 90% or less, even more preferably 32% or more and 80% or less, and even more preferably 42% or more and 73% or less. When the biomass carbon content (%) of the urethane resin (B) is 10% or more, it can exert the effect of reducing environmental load. The lower limit of the biomass carbon content (%) of the flexible packaging laminating ink composition (solids) in this embodiment is preferably 30% or more, 33% or more, 35% or more, 37% or more, 40% or more, 45% or more, 48% or more, and 50% or more, in that order. On the other hand, the upper limit of the biomass carbon content (%) is preferably 100% or less, 90% or less, 80% or less, 73% or less, and 68% or less, in that order. These upper and lower limits can be combined arbitrarily. For example, the preferred range of biomass carbon content (%) for the flexible packaging laminating ink composition (solids) is preferably 30% or more, more preferably 30% or more and 90% or less, even more preferably 32% or more and 80% or less, and even more preferably 42% or more and 73% or less. When the biomass carbon content (%) of the urethane resin (B) is 30% or more, the effect of reducing environmental impact can be achieved. In this specification, "biomass carbon content (%)" refers to radioactive carbon ( １４ The correction value is obtained by multiplying the content ratio (pMC%) of C) by the correction ratio of 0.93, and if the correction value is 100% or more, it is considered to be 100%. Radioactive carbon in this specification ( １４ The content ratio (pMC%) of C) indicates the carbon concentration (mass ratio) of biomass-derived components and is related to the so-called biomass blending ratio. More specifically, radiocarbon (in accordance with ASTM-D6866 (especially ASTM-D6866 B method)１４ C) Radiocarbon obtained by the measurement method ( １４ This is the value of the content ratio of C). Radioactive carbon ( １４ C) has a half-life of 5730 years and nitrogen ( １４ It is known that it has the property of undergoing radioactive decay into N). And, on Earth, radioactive carbon ( １４ C) is carbon dioxide １４ CO ２ After being oxidized and dispersed into the atmosphere, it is taken up by plants and animals through the food chain, and then disappears according to its half-life while circulating in the environment through the food chain. Therefore, radioactive carbon ( １４ C) The measurement method is that fossil fuels are radiocarbon ( １４ C) substantially free of and biomass (or biological)-derived carbon is radioactive carbon in the atmosphere during the period of growth ( １４ It utilizes the fact that C) absorbs radioactive carbon in the carbon contained in biomass (or living organisms) １４ C) Radiocarbon from the ratio ( １４ This is a method for estimating the content ratio (pMC%) of C). Therefore, radioactive carbon ( １４ The higher the content ratio (pMC%) of C), the less fossil fuels are used, and the greater the effect of reducing the environmental burden. Therefore, radioactive carbon ( １４ The content ratio (pMC%) of C) is related to an index indicating the blending ratio of biomass, which is a renewable, biologically derived organic resource (= biomass carbon content (%)). The radioactive carbon contained in the total carbon atoms in the urethane resin (B) (solids) or the flexible packaging laminating ink composition (solids) of this embodiment ( １４ By measuring the proportion of C), the proportion of biomass-derived carbon can be calculated. In this disclosure, using the method described in the Examples section below, the radioactive carbon of urethane resin (B) (solids) or flexible packaging laminating ink composition (solids) can be calculated using the following formula (2) or (3). １４ The content ratio (pMC%) of C) is calculated. Then, as shown in the formula (4) below, the radioactive carbon of the urethane resin (B) (solids) or the ink composition for flexible packaging lamination (solids) is calculated. １４The content ratio (pMC%) of (C) was multiplied by 0.93, and the value taking into account the influence of atmospheric nuclear tests from 1950 to the present was used as the biomass carbon content rate (%). [Formula (2)]: The content ratio (pMC%) of radiocarbon ( １４ C) = [{{radiocarbon ( １４ C) in urethane resin (B) (solid content) ÷ carbon ( １２ C) in urethane resin (B) (solid content)} / {radiocarbon ( １４ C) of standard substance / carbon ( １２ C) of standard substance}} × 100]. [Formula (3)]: The content ratio (pMC%) of radiocarbon ( １４ C) = [{{radiocarbon ( １４ C) in the ink composition for soft package lamination (solid content) ÷ carbon ( １２ C) in the ink composition for soft package lamination (solid content)} / {radiocarbon ( １４ C) of standard substance / carbon ( １２ C) of standard substance}} × 100]. (In the above formulas (2) and (3), the standard substance is oxalic acid (SRM4990C) supplied by the National Institute of Standards and Technology of the United States as a standard substance for dating, which was converted to graphite by the same pretreatment method as the graphite for measurement described in the column of the following examples and used.) [Formula (4)]: Biomass carbon content rate (%) = content ratio (pMC%) of radiocarbon ( １４ C) calculated from the above formula (2) or (3) × 0.93. Incidentally, due to the influence of atmospheric nuclear tests after 1950, about 1.5 times the normal amount of radiocarbon ( １４ C) has been observed due to the artificially injected radiocarbon ( １４ C) into the atmosphere. However, it has been gradually decreasing over time, and the current value is around 107.5 (pMC%). Therefore, in this disclosure as well, similar to the standard of ASTM D6866, radiocarbon ( １４ １４ C) in urethane resin (B) (solid content) １４ ÷ carbon in urethane resin (B) (solid content) １２ C)} / {{radiocarbon of standard substance １４ C) / carbon of standard substance １２ C)}×100] １４ C) in the ink composition for soft package lamination (solid content) １４ ÷ carbon in the ink composition for soft package lamination (solid content) １２ C)} / {{radiocarbon of standard substance １４ C) / carbon of standard substance １２ C)}×100] (In the above formulas (2) and (3), the standard substance is oxalic acid (SRM4990C) supplied by the National Institute of Standards and Technology of the United States as a standard substance for dating, which was converted to graphite by the same pretreatment method as the graphite for measurement described in the column of the following examples and used.) １４ C) content ratio (pMC%) × 0.93 １４ C), about 1.5 times the normal amount of radiocarbon １４ C) has been observed. However, it has been gradually decreasing over time, and the current value is around 107.5 (pMC%). Therefore, in this disclosure as well, similar to the standard of ASTM D6866, radiocarbon １４The biomass carbon content (%) is defined as the value obtained by multiplying the content ratio (pMC%) of C) by 0.93 (= 100 / 107.5). However, even when using the method with the above formula (4), there are cases where a value of 100% or more is calculated. Therefore, in this disclosure, similar to the ASTM standard, if the value of the biomass carbon content (%) is 100% or more, it is considered to be 100%. In this embodiment, radioactive carbon ( １４ The concentration of C) is measured by accelerator mass spectrometry (AMS), which combines a tandem accelerator and a mass spectrometer, to analyze the isotopes of carbon atoms contained in the sample (specifically, １２ C, １３ C, １４ C is one example.) is measured by physically separating the isotopes using an accelerator based on the weight difference of the atoms and measuring the abundance of each individual atom. Furthermore, the sample to be analyzed is either urethane resin (B) (solid content) or a flexible packaging laminate ink composition (solid content), and requires pretreatment. Specifically, as described in the Examples section below, the carbon contained in these samples is oxidized and converted entirely into carbon dioxide. Furthermore, the obtained carbon dioxide is separated from water and nitrogen, and the carbon dioxide is reduced and converted into graphite, which is solid carbon. This obtained graphite is used as the sample for measurement, and Cs ＋ Negative ions of carbon are generated by irradiating with positive ions, and the carbon ions are accelerated using a 3MV tandem accelerator, and the negative ions are converted to positive ions, and then a mass spectrometer is used to analyze them. １２ C ３＋ , １３ C ３＋ , １４ C ３＋ Separate the trajectory of the moving object, １４ C ３＋ The accelerator mass spectrometry method of this embodiment employs a measurement method using an electrostatic analyzer. Furthermore, the carbon isotopes contained in the graphite obtained from the pre-treated sample... １２ C, １３ C and １４ C is accelerated at the same speed, and its flight path is bent by the magnetic field of the mass spectrometry electromagnet. At that time, １２ C,１３ C is on the inside, the heaviest １４ C flies along the outermost edge of the curve. Also, １２ C, １３ Because the amount of C is large, it is expressed as an electric current by a Faraday cup detector. １４ Each C atom is counted individually by an ionization chamber-type ion detector.

[0072] The hydroxyl value of the polyester polyol (b2) in this embodiment is preferably 15 mg KOH / g to 285 mg KOH / g, more preferably 18 mg KOH / g to 285 mg KOH / g, even more preferably 20 mg KOH / g to 165 mg KOH / g, and even more preferably 20 mg KOH / g to 115 mg KOH / g. When the hydroxyl value of the polyester polyol (b2) is within the above range, it is easier to control the urethane bond concentration to a predetermined value or higher, which can further improve the laminate strength. The hydroxyl value of the polyether polyol (b3) in this embodiment is preferably 15 mg KOH / g to 285 mg KOH / g, more preferably 18 mg KOH / g to 285 mg KOH / g, even more preferably 20 mg KOH / g to 165 mg KOH / g, and even more preferably 20 mg KOH / g to 115 mg KOH / g. When the hydroxyl value of the polyether polyol (b3) is within the above range, it is easier to control the urethane bond concentration to a predetermined value or higher, which can further improve the laminate strength.

[0073] The urethane bond concentration of the urethane resin (B) in this embodiment is preferably 0.6 mmol / g or more, more preferably 0.7 mmol / g or more and 2.5 mmol / g or less, and even more preferably in the range of 0.8 mmol / g or more and 2.0 mmol / g or less. When the urethane bond concentration is 0.6 mmol / g or more, the laminate strength tends to be particularly excellent. The urethane bond concentration can be calculated by the following formula (5). [Formula (5)]: Urethane bond concentration = {(W ｂ１ ×OH ｂ１ +W ｂ２ ×OH ｂ２ +W ｂ３ ×OH ｂ３ +W ｂ４ ×OH ｂ４ +Wｂ５ ×OH ｂ５ +W ｂ６ ×OH ｂ６ +..・・・+W ｂｊ ×OH ｂｊ +W ｂｋ ×OH ｂｋ ) × 1000} / (56100 × S ２ In the above formula (5), the following applies to each: W ｂ１ Weight of polyester polyol (b2-1) OH ｂ１ : Hydroxyl value of polyester polyol (b2-1) W ｂ２ : Weight of polyether polyol (b3-1) OH ｂ２ : Hydroxyl value of polyether polyol (b3-1) W ｂ３ Weight of polyester polyol (b2-2) OH ｂ３ : Hydroxyl value of polyester polyol (b2-2) W ｂ４ : Weight of polyether polyol (b3-2) OH ｂ４ : Hydroxyl value of polyether polyol (b3-2) W ｂ５ Weight of polyester polyol (b2-3) OH ｂ５ : Hydroxyl value of polyester polyol (b2-3) W ｂ６ : Weight of polyether polyol (b3-3) OH ｂ６ : Hydroxyl value of polyether polyol (b3-3) W ｂｊ Weight of polyester polyol (b3-j) OH ｂｊ : Hydroxyl value of polyester polyol (b3-j) W ｂｋ : Weight of polyether polyol (b3-k) OH ｂｋ : Hydroxyl value of polyether polyol (b3-k) S ２: Weight of solid content of urethane resin (B) Note that in the above formula (5), polyester polyol (b2-1), polyester polyol (b2-2), polyester polyol (b2-3), ..., polyester polyol (b3-j) are all included in polyester polyol (b2). In addition, polyether polyol (b3-1), polyether polyol (b3-2), polyether polyol (b3-3), ..., polyether polyol (b3-k) are all included in polyether polyol (b3). In other words, when j-type polyester polyols (b2) and k-type polyether polyols (b3) are used as reaction raw materials for urethane resin (B), the numerator of formula (5) above is the sum of the product of the amount of each j-type polyester polyol (b2) and the hydroxyl value of each polyester polyol (b2), and the sum of the product of the amount of each k-type polyether polyol (b3) and the hydroxyl value of each polyether polyol (b3). The denominator of formula (5) above is the value obtained by multiplying S, which is the weight of the solid content of the obtained urethane resin (B), by 56100.

[0074] A preferred embodiment of the flexible packaging lamination ink composition according to this embodiment is that it contains a urethane resin component comprising a urethane resin (A) having a partial structure represented by the general formula (I) above, and a urethane resin (B) having a urethane bond concentration of 0.6 mmol / g or more and possessing both urea and urethane bonds. This makes it possible to provide a flexible packaging lamination ink composition that can form an ink layer with superior fluidity, adhesion, blocking resistance, PEEL strength, and dry lamination strength. In particular, the interaction between the polar groups on the film surface and the urethane bonds of the urethane resin component tends to further improve adhesion to the substrate. Furthermore, conditions for making the urethane bond concentration of urethane resin (B) 0.6 mmol / g or more include (i) lowering the total molecular weight of the polyol components used in the reaction raw material (II) of urethane resin (B), and (ii) adjusting the hydroxyl value and blending ratio of the total polyol components blended in the reaction raw material (II).

[0075] (Method for producing urethane resins (A) and (B)) The polyurethane resins (A) and (B) in the flexible packaging laminating ink composition of this embodiment can be produced by, for example, a two-step method in which a polyol compound and a diisocyanate compound are reacted in proportion to an excess of isocyanate groups to obtain a prepolymer with terminal isocyanate groups, and then the obtained prepolymer is reacted with a chain extender and / or end-canceling agent in a suitable solvent, or by a one-step method in which the polyol compound, diisocyanate compound, chain extender and / or end-canceling agent are reacted at once in a suitable solvent from among the above. The polyol compound can be one or more selected from the group consisting of polyols (a2), polyester polyols (b2), and polyether polyols (b3) (specifically, polypropylene glycol) having a number average molecular weight (Mn) of 700 to 900, and a combined polyol which may be added as needed. The diisocyanate compound can be one or more compounds selected from the group consisting of organic diisocyanate compounds (a1) and aromatic polyisocyanate compounds (b1). The solvent can be an ester solvent such as ethyl acetate, propyl acetate, or butyl acetate, which are commonly used as solvents for non-toluene gravure inks; a ketone solvent such as acetone, methyl ethyl ketone, or methyl isobutyl ketone; an alcohol solvent such as methanol, ethanol, isopropyl alcohol, or n-butanol; a hydrocarbon solvent such as methylcyclohexane or ethylcyclohexane; or a mixture thereof. Among the above methods, the two-stage method is preferred to obtain a uniform urethane resin (B). Furthermore, when producing urethane resin (B) by the two-stage method, it is preferable to react them so that the total (equivalent ratio) of amino groups of the chain extender and / or end-canceling agent is in a ratio of 1 / 0.9 to 1.3. When the equivalent ratio of isocyanate groups to amino groups is less than 1 / 1.3, chain extenders and / or end-canceling agents may remain unreacted, potentially causing yellowing of the polyurethane resin or the generation of an odor after printing. Furthermore, in recent years, from the perspective of the working environment, it has become more preferable to avoid using aromatic solvents such as toluene and xylene, as well as ketone solvents.In the flexible packaging laminating ink composition of this embodiment, the chain extenders used in the polyurethane resin include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, and amines having a hydroxyl group in the molecule, such as 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyropyrethylenediamine, di-2-hydroxypyropyrethylenediamine, and di-2-hydroxypropylethylenediamine. These chain extenders can be used individually or in combination of two or more. Furthermore, monovalent active hydrogen compounds can be used as end-sealing agents for reaction termination. Examples of such compounds include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. Furthermore, when it is particularly desirable to introduce carboxyl groups into polyurethane resin, amino acids such as glycine and L-alanine can be used as reaction stoppers. These end-capping agents can be used individually or in combination of two or more.

[0076] (Resin (C) with a glass transition temperature (Tg) of 40°C or higher) The flexible packaging laminating ink composition of this embodiment may optionally contain a resin (C) with a glass transition temperature (Tg) of 40°C or higher. This allows for good blocking resistance, resolubility, and ink film properties. The resin (C) with a glass transition temperature (Tg) of 40°C or higher is not particularly limited as long as it has a glass transition temperature (Tg) of 40°C or higher, but it is preferably one or more selected from the group consisting of polyvinyl butyral resins, cellulose resins, and vinyl chloride-vinyl acetate copolymer resins. For example, when emphasizing the reduction of environmental impact, the resin (C) with a glass transition temperature (Tg) of 40°C or higher is preferably a polyvinyl butyral resin or a cellulose resin. On the other hand, when emphasizing dispersibility, it is preferably a polyvinyl butyral resin or a vinyl chloride-vinyl acetate copolymer resin. In this embodiment, the lower limit of the content of resin (C) having a glass transition temperature (Tg) of 40°C or higher relative to the total resin solids content (100% by mass) of the ink composition is preferably 0.1% by mass or more, 0.3% by mass or more, 0.5% by mass or more, 1.7% by mass or more, 2.2% by mass or more, or 2.8% by mass or more. On the other hand, the upper limit of the content of resin (C) having a glass transition temperature (Tg) of 40°C or higher is preferably 30% by mass or less, 28% by mass or less, 27% by mass or less, 26% by mass or less, 25% by mass or less, or 22% by mass or less. The range of the resin (C) content is preferably 0.1% by mass to 30% by mass, 1.7% by mass to 27% by mass, and 2.8% by mass to 27% by mass, in that order. A range of 0.1% by mass to 30% by mass for the resin (C) content is preferable from the viewpoint of improving film properties such as blocking resistance and ensuring pigment dispersibility. The above upper and lower limits can be combined as appropriate. Below, preferred embodiments of the resin (C) having a glass transition temperature (Tg) of 40°C or higher are described in detail: polyvinyl butyral resins, cellulose resins, and vinyl chloride-vinyl acetate copolymer resins.

[0077] <Polyvinyl Butyral Resin> The flexible packaging lamination ink composition of this embodiment preferably contains a polyvinyl butyral resin as the resin (C) having a glass transition temperature (Tg) of 40°C or higher. This polyvinyl butyral resin has binding and dispersing properties as a binder resin, and since its constituent elements are only carbon atoms, hydrogen atoms, and oxygen atoms, it has the effect of being more environmentally friendly than vinyl chloride-vinyl acetate copolymer resins. Furthermore, when the flexible packaging lamination ink composition contains a pigment, when the pigment is dispersed by kneading with a polyvinyl butyral resin, a suitable group from among butyral groups, polyvinyl alcohol residues, and vinyl acetate residues is adsorbed onto the pigment, and steric hindrance occurs due to the bulky butyral groups, resulting in superior dispersion stability compared to dispersing the pigment with polyurethane resin (A). As the polyvinyl butyral resin of this embodiment, there are no particular limitations, and any known resin can be used. Generally, as a polyvinyl butyral resin, a reaction product obtained by acetalizing polyvinyl alcohol with an aldehyde compound such as butyraldehyde using a known reaction can be used. The polyvinyl butyral resin of this embodiment has the following general formula (iii-1):

[0078] (In the above general formula (iii-1), n1 and n2 are independent integers of 1 or more, R ６ It is preferable that the substructure is represented by ) where R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. In the above general formula (iii-1), ６ R preferably represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 7 carbon atoms, and even more preferably a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms. Examples of the hydrocarbon group include alkyl groups, alkenyl groups, aryl groups, or aralkyl groups, and may be linear, branched, or cyclic. Among these, alkyl groups are preferred. Among these, R ６A propyl group or an isopropyl group is more preferable. As described above, the polyvinyl butyral resin of this embodiment is a resin that uses polyvinyl alcohol and an aldehyde compound as reaction raw materials. In this case, the aldehyde compound is R ６ When expressed as -C(=O)H, R in the above general formula (iii-1) ６ This is a hydrocarbon group derived from an aldehyde compound used in the synthesis of polyvinyl butyral resins.

[0079] The preferred polyvinyl butyral resin of this embodiment is preferably a resin having a substructure represented by the above general formula (iii-1), a substructure represented by the following general formula (iii-2), and a substructure represented by the following general formula (iii-2).

[0080] (In the above general formula (iii-2), n3 are each independent integers greater than or equal to 1, and R ７ (This represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.)

[0081] (In the above general formula (iii-3), n4 are each independent integers greater than or equal to 1.)

[0082] In the above general formula (iii-2), R ７ R preferably represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. ７For example, hydrogen atoms, methyl groups, ethyl groups, propyl groups, isopropyl groups, n-butyl groups, isobutyl groups, sec-butyl groups, or tert-butyl groups are more preferred. Furthermore, when the polyvinyl butyral resin of this embodiment is represented as a resin having a substructure represented by the above general formula (iii-1), a substructure represented by the following general formula (iii-2), and a substructure represented by the following general formula (iii-3), the content of the substructure represented by the above general formula (iii-2) relative to the total amount of the polyvinyl butyral resin is preferably 12% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less. By setting the content of the substructure represented by the above general formula (iii-2) in the polyvinyl butyral resin within the above range, an ink layer with an excellent balance of fluidity and dispersibility can be obtained.

[0083] The weight-average molecular weight of the polyvinyl butyral resin in this embodiment is preferably 5,000 to 150,000, more preferably 6,000 to 100,000, and even more preferably 7,000 to 50,000. By setting the weight-average molecular weight of the polyvinyl butyral resin within the above range, excellent curability is achieved, and both the strength of the coating film and appropriate flexibility can be obtained. Furthermore, polyvinyl butyral resins with a weight-average molecular weight of 5,000 to 150,000 are readily available, and by using such polyvinyl butyral resins, an ink layer with an excellent balance of fluidity and dispersibility can be obtained.

[0084] The glass transition temperature (hereinafter sometimes referred to as Tg) of the polyvinyl butyral resin in this embodiment is preferably in the range of 50°C to 120°C, more preferably in the range of 55°C to 115°C, and more preferably in the range of 60°C to 110°C. In this invention, the glass transition temperature is obtained by measurement using a differential scanning calorimeter.

[0085] The hydroxyl value of the polyvinyl butyral resin in this embodiment is preferably in the range of 10% to 40% by mass, and more preferably in the range of 15% to 30% by mass. By setting the amount of hydroxyl groups in the polyvinyl butyral resin within the above range, an ink layer with an excellent balance of fluidity and dispersibility can be obtained. The amount of hydroxyl groups refers to the amount of the substructure represented by the above general formula (iii-3) relative to the total amount of the polyvinyl butyral resin.

[0086] The amount of acetyl groups in the polyvinyl butyral resin is preferably 8% by mass or less, and more preferably 5% by mass or less. By setting the amount of acetyl groups in the polyvinyl butyral resin within the above range, an ink layer with an excellent balance of fluidity and dispersibility can be obtained. The amount of acetyl groups refers to the amount of R in the substructure represented by the general formula (iii-2) above. ７ When the substructure is a methyl group, it is called an acetyl group, and the amount of that acetyl group is the content relative to the total amount of polyvinyl butyral resin.

[0087] The content (solids) of polyvinyl butyral resin in the ink composition is preferably 0.1% to 5% by mass, more preferably 0.1% to 4.0% by mass, and most preferably 0.2% to 3.0% by mass, relative to the total resin solids (100% by mass) of the ink composition. Adding 0.1% by mass or more of polyvinyl butyral resin tends to maintain the adhesion and transferability of the ink film, while keeping the total at 5% by mass or less maintains the lamination strength of the ink. Furthermore, the lower limit of the solids mass ratio in the ink composition is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and most preferably 0.3% by mass or more. Furthermore, the upper limit of the solids mass ratio in the ink composition is preferably 45% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, even more preferably 20% by mass or less, even more preferably 15% by mass or less, and particularly preferably 10% by mass or less.

[0088] <Cellulose-based resins> Examples of the above-mentioned cellulose-based resins include cellulose ester resins such as cellulose acetate propionate, cellulose acetate butyrate, and other cellulose ester resins; nitrocellulose (also called nitrated cotton); hydroxyalkylcellulose; and carboxyalkylcellulose. The cellulose ester resin preferably has an alkyl group, and examples of such alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, and hexyl groups, and the alkyl group may also have substituents. Among the above-mentioned cellulose-based resins, cellulose acetate propionate, cellulose acetate butyrate, and nitrocellulose are preferred, and cellulose acetate propionate and cellulose acetate butyrate are particularly preferred. The molecular weight is preferably 5,000 to 200,000 by weight average molecular weight, and more preferably 10,000 to 50,000. Furthermore, a glass transition temperature of 120°C to 180°C is even more preferred. The combined use of the polyurethane resin of the present invention is expected to improve blocking resistance, scratch resistance, and other properties of the ink film. Nitrocellulose (nitrated cotton) is preferably obtained as a nitrate ester by reacting natural cellulose with nitric acid, in which three hydroxyl groups in the six-membered ring of the anhydrous glucopyranose group in natural cellulose are replaced with nitrate groups.

[0089] The content (solids) of cellulose-based resin is preferably 0.1% to 5% by mass, more preferably 0.1% to 4.0% by mass, and most preferably 0.2% to 3.0% by mass, relative to the total resin solids (100% by mass) of the ink composition. By setting the content of cellulose-based resin to a range of 0.2% to 3.0% by mass, the effect of anti-blocking properties can be achieved.

[0090] <Vinyl Chloride-Vinyl Acetate Copolymer Resin> The vinyl chloride-vinyl acetate copolymer resin described above is a copolymer of vinyl chloride monomer and vinyl acetate monomer. Therefore, the vinyl chloride-vinyl acetate copolymer resin contains vinyl chloride monomer units and vinyl acetate monomer units. In addition, the vinyl chloride-vinyl acetate copolymer resin may contain monomer units other than vinyl chloride monomer units and vinyl acetate monomer units (other monomers) as needed. The other monomers are not particularly limited as long as they can be copolymerized with vinyl chloride and vinyl acetate. The vinyl chloride-vinyl acetate copolymer resin preferably has a hydroxyl value of 50 mg KOH / g to 200 mg KOH / g. Furthermore, the content of vinyl chloride monomer units is preferably 70% to 98% by mass, more preferably 80% to 95% by mass, based on the total amount of the vinyl chloride-vinyl acetate copolymer resin. When the content of vinyl chloride monomer units is within the above range, better blocking resistance can be exhibited. The content of the vinyl acetate monomer units is preferably 2% to 30% by mass, more preferably 5% to 20% by mass, relative to the total amount of the vinyl chloride-vinyl acetate copolymer resin. When the content of vinyl acetate monomer units is within the above range, the resin is flexible and has excellent adhesion.

[0091] In this embodiment, the mass ratio of the total polyurethane resin component to the vinyl chloride-vinyl acetate copolymer resin in terms of solid content (polyurethane resin component: vinyl chloride-vinyl acetate copolymer resin) in the flexible packaging lamination ink composition is preferably 60:40 to 100:0, and more preferably 70:30 to 100:0. Including vinyl chloride-vinyl acetate copolymer resin improves lamination suitability and pigment dispersibility. On the other hand, from the viewpoint of reducing environmental impact, it is preferable not to contain vinyl chloride-vinyl acetate copolymer resin, or to contain a smaller amount. Furthermore, in this embodiment, by further reducing the content of vinyl chloride-vinyl acetate copolymer resin in the flexible packaging lamination ink composition, the recyclability of the flexible packaging material using the ink can be improved. When vinyl chloride-based resins such as vinyl chloride-vinyl acetate copolymer resin are included, corrosion of recycling equipment occurs, but by further reducing the content of vinyl chloride-based monomers, corrosion of recycling equipment can be prevented.

[0092] (Preferred Embodiments of Laminating Ink Composition for Flexible Packaging) The total urethane resin component content in the laminating ink composition for flexible packaging of this embodiment is preferably 30% to 100% by mass, more preferably 40% to 99% by mass, and even more preferably 50% to 95% by mass, relative to the total resin solids content of the laminating ink composition for flexible packaging. The urethane bond concentration of the total urethane resin component in the laminating ink composition for flexible packaging of this embodiment is preferably 4.0 mmol / g or more, more preferably 5.0 mmol / g to 20 mmol / g, and even more preferably in the range of 6.0 mmol / g to 18 mmol / g. When the urethane bond concentration of the total urethane resin component is 4.0 mmol / g or more, the urethane bonds of the urethane resin component in the ink layer interact with the polar groups on the film surface, improving adhesion to the substrate and resulting in a tendency for superior lamination strength. The urethane bond concentration of the total urethane resin components is calculated from the mass of the solids of the total urethane resin components and the hydroxyl value of the total polyol compounds used as reaction raw materials for the total urethane resin components, in the same manner as formulas (1) and (5) above. The total urethane resin components refer to the resins (binding resins (solids)) contained in the flexible packaging lamination ink composition that have urethane bonds. Therefore, the total urethane resin components must contain urethane resin (A), and may also contain urethane resin (B) or polyurethane resins other than urethane resins (A) and (B). By adjusting the amount of urethane resin components and the urethane bond concentration in the entire flexible packaging lamination ink composition to the above range, particularly excellent dry lamination strength can be achieved. In the flexible packaging lamination ink composition of this embodiment, the total content of urethane resin (A), urethane resin (B), resin (C) having a glass transition temperature (Tg) of 40°C or higher, and other resins described later is preferably 70% to 100% by mass, 80% to 100% by mass, 90% to 100% by mass, 93% to 100% by mass, 95% to 100% by mass, 96% to 100% by mass, or 97.1% to 100% by mass, relative to the total resin solids content (100% by mass) of the flexible packaging lamination ink composition.

[0093] (Other Resins) The ink composition for flexible packaging lamination of this embodiment may contain other resins that can be used in combination in the ink technology field, in addition to urethane resin (A) and urethane resin (B) which may be added as needed. The other resin may be a binder resin or a dispersion resin, but it is preferable to add it as a binder resin. Examples of other resins that can be used in combination include ethylene-vinyl acetate copolymer resin, vinyl acetate resin, polyamide resin, acrylic resin, polyester resin, alkyd resin, rosin-based resin, rosin-modified maleic acid resin, ketone resin, cyclized rubber, petroleum resin, polyurethane resin other than urethane resins (A) and (B), etc. In particular, it is preferable to contain at least one resin selected from polyester resin, acrylic resin, polyamide resin, and rosin-modified maleic acid resin, as this can improve blocking resistance and resolubility. Furthermore, it is preferable from the viewpoint of reducing environmental impact that the ink composition of this disclosure does not contain chlorine-based resins. These resins can be used individually or in mixtures of two or more. The content of the combined resin is preferably 0.1% to 25% by mass, and more preferably 2% to 15% by mass, relative to the total mass of the ink composition.

[0094] <Rosin-Modified Maleic Acid Resin> The rosin-modified maleic acid resin described above is an alkyd resin obtained by reacting a polyhydric alcohol such as glycerin, pentaerythritol, or ethylene glycol with an adduct formed by the Diels-Alder reaction between rosin and maleic acid. The acid value is determined by the proportion of the polyhydric alcohol reacted with the rosin-maleic acid adduct and the degree of esterification. In addition to polyhydric alcohols, polybasic acids may also be used to form a structure in which a long-chain alkyd resin is bonded to the rosin skeleton.

[0095] Examples of polyhydric alcohols used to react with the adduct of rosin and maleic acid include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, trimethylolpropane, glycerin, pentaerythritol, and sorbitol. Polybasic acids used as raw materials for alkyd resins along with these polyhydric alcohols include phthalic anhydride, terephthalic acid, isophthalic acid, adipic acid, maleic acid, itaconic acid, succinic acid, and sebacic acid.

[0096] Furthermore, for example, a compound having a carbon-carbon unsaturated double bond, such as maleic acid, may be used as a raw material for the above-mentioned alkyd resin, and a styrene monomer may be reacted with it to produce a rosin-modified styrene-maleic acid resin, which is also included in rosin-modified maleic acid resin.

[0097] (Pigments) The pigment used in the ink composition for flexible packaging lamination according to this embodiment may be either a colored pigment or a white pigment. The pigment is not particularly limited, and examples include inorganic pigments and organic pigments used in general inks, paints, and recording agents. In order to particularly exhibit the excellent effect of the present invention, which is to improve storage stability, the pigment is preferably an organic pigment. Examples of organic pigments include soluble azo pigments, insoluble azo pigments, azo pigments, phthalocyanine pigments, halogenated phthalocyanine pigments, anthraquinone pigments, anthensrone pigments, dianthraquinonyl pigments, anthrapyrimidine pigments, perylene pigments, perinone pigments, quinacridone pigments, thioindigo pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, azomethine azo pigments, flavanthrone pigments, diketopyrrolopyrrole pigments, isoindoline pigments, indanthrone pigments, and carbon black pigments. Other examples include carmine 6B, lake red C, permanent red 2B, disazo yellow, pyrazolone orange, carmine FB, chromophthal yellow, chromophthal red, phthalocyanine blue, phthalocyanine green, dioxazine violet, quinacridone magenta, quinacridone red, indanthrone blue, pyrimidine yellow, thioindigobordeaux, thioindigomagenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, and daylight fluorescent pigments. Both unacidified and acidified pigments can be used. Examples of the organic pigments include black, blue, green, red, purple, yellow, orange, and brown pigments. Preferred specific examples of each organic pigment are given below.

[0098] Examples of black pigments include C.I. Pigment Black 1, C.I. Pigment Black 6, C.I. Pigment Black 7, C.I. Pigment Black 9, and C.I. Pigment Black 20.

[0099] Examples of indigo pigments include C.I. Pigment Blue 15, C.I. Pigment Blue 15:1, C.I. Pigment Blue 15:2, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 15:5, C.I. Pigment Blue 15:6, C.I. Pigment Blue 16, C.I. Pigment Blue 17:1, C.I. Pigment Blue 22, C.I. Pigment Blue 24:1, C.I. Pigment Blue 25, C.I. Pigment Blue 26, C.I. Pigment Blue 60, C.I. Pigment Blue 61, C.I. Pigment Blue 62, C.I. Pigment Blue 63, C. Examples include I. Pigment Blue 64, C.I. Pigment Blue 75, C.I. Pigment Blue 79, C.I. Pigment Blue 80, etc.

[0100] Examples of green pigments include C.I. Pigment Green 1, C.I. Pigment Green 4, C.I. Pigment Green 7, C.I. Pigment Green 8, C.I. Pigment Green 10, and C.I. Pigment Green 36.

[0101] Examples of red pigments include C.I. Pigment Red 1, C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 4, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 8, C.I. Pigment Red 9, C.I. Pigment Red 10, C.I. Pigment Red 11, C.I. Pigment Red 12, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 17, C.I. Pigment Red 18, C.I. Pigment Red 19, C.I. Pigment Red 20, C.I. Pigment Red 21, C. I. Pigment Red 22, C. I. Pigment Red 23, C. I. Pigment Red 31, C. I. Pigment Red 32, C. I. Pigment Red 38, C. I. Pigment Red 41, C. I. Pigment Red 43, C. I. Pigment Red 46, C. I. Pigment Red 48, C. I. Pigment Red 48:1, C. I. Pigment Red 48:2, C. I. Pigment Red 48:3, C. I. Pigment Red 48:4, C. I. Pigment Red 48:5, C. I. Pigment Red 48:6, C. I. Pigment Red 49, C. I. Pigment Red 49:1, C. I. Pigment Red 49:2, C.I. Pigment Red 49:3, C.I. Pigment Red 52, C.I. Pigment Red 52:1, C.I. Pigment Red 52:2, C.I. Pigment Red 53, C.I. Pigment Red 53:1, C.I. Pigment Red 53:2, C.I. Pigment Red 53:3, C.I. Pigment Red 54, C.I. Pigment Red 57, C.I. Pigment Red 57:1, C.I. Pigment Red 58, C.I. Pigment Red 58:1, C.I. Pigment Red 58:2, C.I. Pigment Red 58:3, C.I. Pigment Red 58:4, C.I. Pigment Red 60:1, C.I. Pigment Red 63, C.I. Pigment Red 63:1, C.I. Pigment Red 63:2, C.I. Pigment Red 63:3, C.I. Pigment Red 64:1, C.I. Pigment Red 68, C.I. Pigment Red 68, C.I. Pigment Red 81:1, C.I. Pigment Red 83,C.I. Pigment Red 88, C.I. Pigment Red 89, C.I. Pigment Red 95, C.I. Pigment Red 112, C.I. Pigment Red 114, C.I. Pigment Red 119, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 136, C.I. Pigment Red 144, C.I. Pigment Red 146, C.I. Pigment Red 147, C.I. Pigment Red 149, C.I. Pigment Red 150, C.I. Pigment Red 164, C.I. Pigment Red 166, C.I. Pigment Red 168, C.I. Pigment Red 169, C.I. Pigment Red 170, C.I. Pigment Red 171, C.I. Pigment Red 172, C.I. Pigment Red 175, C.I. Pigment Red 176, C.I. Pigment Red 177, C.I. Pigment Red 178, C.I. Pigment Red 179, C.I. Pigment Red 180, C.I. Pigment Red 181, C.I. Pigment Red 182, C.I. Pigment Red 183, C.I. Pigment Red 184, C.I. Pigment Red 185, C.I. Pigment Red 187, C.I. Pigment Red 188, C.I. Pigment Red 190, C.I. Pigment Red 192, C.I. Pigment Red 193, C.I. Pigment Red 194, C.I. Pigment Red 200, C.I. Pigment Red 202, C.I. Pigment Red 206, C.I. Pigment Red 207, C.I. Pigment Red 208, C.I. Pigment Red 209, C.I. Pigment Red 210, C.I. Pigment Red 211, C.I. Pigment Red 213, C.I. Pigment Red 214, C.I. Pigment Red 216, C.I. Pigment Red 215, C.I. Pigment Red 216, C.I. Pigment Red 220, C.I. Pigment Red 221, C.I. Pigment Red 223, C.I. Pigment Red 224, C.I. Pigment Red 226, C.I. Pigment Red 237, C.I. Pigment Red 238, C.I. Pigment Red 239, C.I. Pigment Red 240, C.I. Pigment Red 242, C.I. Pigment Red 245,C.I. Pigment Red 247, C.I. Pigment Red 248, C.I. Pigment Red 251, C.I. Pigment Red 253, C.I. Pigment Red 254, C.I. Pigment Red 255, C.I. Pigment Red 256, C.I. Pigment Red 257, C.I. Pigment Red 258, C.I. Pigment Red 260, C.I. Pigment Red 262, C.I. Pigment Red 263, C.I. Pigment Red 264, C.I. Pigment Red 266, C.I. Pigment Red 268, C.I. Pigment Red 269, C.I. Pigment Red 270, C.I. Examples include Pigment Red 271, C.I. Pigment Red 272, C.I. Pigment Red 279, etc.

[0102] Examples of purple pigments include C.I. Pigment Violet 1, C.I. Pigment Violet 2, C.I. Pigment Violet 3, C.I. Pigment Violet 3:1, C.I. Pigment Violet 3:3, C.I. Pigment Violet 5:1, C.I. Pigment Violet 13, C.I. Pigment Violet 19 (γ-type, β-type), C.I. Pigment Violet 23, C.I. Pigment Violet 25, C.I. Pigment Violet 27, C.I. Pigment Violet 29, C.I. Pigment Violet 31, C.I. Pigment Violet 32, C.I. Pigment Violet 36, C.I. Pigment Violet 37, C.I. Examples include Pigment Violet 38, C.I. Pigment Violet 42, C.I. Pigment Violet 50, etc.

[0103] Examples of yellow pigments include C.I. Pigment Yellow 1, C.I. Pigment Yellow 3, C.I. Pigment Yellow 12, C.I. Pigment Yellow 13, C.I. Pigment Yellow 14, Pigment Yellow 17, C.I. Pigment Yellow 24, C.I. Pigment Yellow 42, C.I. Pigment Yellow 55, C.I. Pigment Yellow 62, C.I. Pigment Yellow 65, C.I. Pigment Yellow 74, C.I. Pigment Yellow 83, C.I. Pigment Yellow 86, C.I. Pigment Yellow 93, C.I. Pigment Yellow 94, C.I. Pigment Yellow 95, C.I. Pigment Yellow 109, C.I. Pigment Yellow 110, C.I. Pigment Yellow 117, C.I. Pigment Yellow 120, Pigment Yellow 125, C.I. Pigment Yellow 128, C.I. Pigment Yellow 129, C.I. Pigment Yellow 137, C.I. Pigment Yellow 138, C.I. Pigment Yellow 139, C.I. Pigment Yellow 147, C.I. Pigment Yellow 148, C.I. Pigment Yellow 150, C.I. Pigment Yellow 151, C.I. Pigment Yellow 153, C.I. Pigment Yellow 154, C.I. Pigment Yellow 155, C.I. Pigment Yellow 166, C.I. Pigment Yellow 168, C. Examples include I. Pigment Yellow 174, C. I. Pigment Yellow 180, C. I. Pigment Yellow 185, and C. I. Pigment Yellow 213.

[0104] Examples of orange pigments include C.I. Pigment Orange 5, C.I. Pigment Orange 13, C.I. Pigment Orange 16, C.I. Pigment Orange 34, C.I. Pigment Orange 36, C.I. Pigment Orange 37, C.I. Pigment Orange 38, C.I. Pigment Orange 43, C.I. Pigment Orange 51, C.I. Pigment Orange 55, C.I. Pigment Orange 59, C.I. Pigment Orange 61, C.I. Pigment Orange 64, C.I. Pigment Orange 71, or C.I. Pigment Orange 74.

[0105] Examples of brown pigments include C.I. Pigment Brown 23, C.I. Pigment Brown 25, or C.I. Pigment Brown 26.

[0106] Among them, preferred pigments include: C.I. Pigment Black 7 as a black pigment; C.I. Pigment Blue 15, C.I. Pigment Blue 15:1, C.I. Pigment Blue 15:2, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 15:6 as indigo pigments; C.I. Pigment Green 7 as a green pigment; and C.I. Pigment Red 57:1, C.I. Pigment Red 48:1, C.I. Pigment Red 48:2, C.I. Pigment Red 48:3, C.I. Pigment Red 146, C.I. Pigment Red 242, C.I. Pigment Red 185, C.I. Examples include Pigment Red 122, C.I. Pigment Red 178, C.I. Pigment Red 149, C.I. Pigment Red 144, C.I. Pigment Red 166, as purple pigments C.I. Pigment Violet 23, C.I. Pigment Violet 37, as yellow pigments C.I. Pigment Yellow 83, C.I. Pigment Yellow 14, C.I. Pigment Yellow 180, C.I. Pigment Yellow 139, as orange pigments C.I. Pigment Orange 38, C.I. Pigment Orange 13, C.I. Pigment Orange 34, C.I. Pigment Orange 64, etc. It is preferable to use at least one or more selected from this group.

[0107] Examples of the inorganic pigments include white inorganic pigments such as titanium dioxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, litsubone, antimony white, and gypsum. Among the inorganic pigments, the use of titanium dioxide is particularly preferred. Titanium dioxide is white and is preferred in terms of coloring power, opacity, chemical resistance, and weather resistance, and from the viewpoint of printing performance, titanium dioxide that has been treated with silica and / or alumina is preferred.

[0108] Examples of inorganic pigments other than white include carbon black, aluminum particles, mica, bronze powder, chrome vermilion, lead yellow, cadmium yellow, cadmium red, ultramarine, Prussian blue, red iron oxide, yellow iron oxide, iron black, and zircon. Aluminum is available in powder or paste form, but it is preferable to use it in paste form for ease of handling and safety reasons. Whether to use leafing or non-leafing aluminum is selected appropriately from the viewpoint of brightness and density.

[0109] The pigment is used in an amount sufficient to ensure the concentration and coloring power of the ink composition, that is, the pigment content is preferably 1% to 60% by mass, and more preferably 5% to 60% by mass, relative to the total amount (100% by mass) of the ink composition for flexible packaging lamination. The solid content ratio in the ink composition for flexible packaging lamination is preferably 10% to 90% by mass relative to the total amount of resin solids in the ink composition. The pigment can be used alone or in combination of two or more types.

[0110] (Additives) The flexible packaging laminating ink composition of this embodiment preferably further contains one or more additives selected from the group consisting of extender pigments, pigment dispersants, leveling agents, defoaming agents, waxes, dispersants, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, and flame retardants, if necessary. In the flexible packaging laminating ink composition of this embodiment, the content of additives (solids) relative to the total amount of the ink composition is preferably 0.1% by mass to 20.0% by mass.

[0111] The ink composition for flexible packaging lamination according to this embodiment may further contain a dispersant as needed. To stably disperse the pigment in an organic solvent, the resin alone can be used, but a dispersant can also be used in combination to further stably disperse the pigment. As the dispersant, surfactants such as anionic, nonionic, cationic, and amphoteric surfactants can be used. Examples include comb-structured polymer compounds obtained by adding polyester to polyethyleneimine, or alkylamine derivatives of α-olefin maleic acid polymers. Specifically, examples include the Solspers series (ZENECA), Azisper series (Ajinomoto), and Homogenol series (Kao). In addition, the BYK series (BIK Chemie) and EFKA series (EFKA) can also be used as appropriate. From the viewpoint of storage stability of the ink, the dispersant is preferably included in the ink at a concentration of 0.05% by mass or more relative to the total mass of the ink composition, and from the viewpoint of lamination suitability, at a concentration of 5% by mass or less, and more preferably in the range of 0.1% to 2% by mass.

[0112] (Organic Solvents) Various organic solvents can be used as the organic solvent in the flexible packaging laminating ink composition of this embodiment. Examples include aromatic organic solvents such as toluene and xylene, ketone-based organic solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, ester-based organic solvents such as ethyl acetate, n-propyl acetate, butyl acetate, and propylene glycol monomethyl ether acetate, and alcohol-based organic solvents such as n-propanol, inopropanol, n-butanol, and propylene glycol monomethyl ether. These can be used individually or in mixtures of two or more. In recent years, from the viewpoint of the working environment, it is preferable not to use aromatic organic solvents such as toluene and xylene, or ketone-based organic solvents.

[0113] The above organic solvent preferably contains the above ester-based organic solvent and alcohol-based organic solvent, and it is preferable to set the mass ratio so that the ester-based organic solvent : alcohol-based organic solvent = 1:1 to 9:1. When the mass ratio in the organic solvent is within this range, an ink with excellent printability and blocking resistance can be obtained. The mass ratio is more preferably 2:1 to 9:1, and even more preferably 2:1 to 8:1.

[0114] The flexible packaging lamination ink composition of this embodiment may contain water as a volatile component along with the organic solvent. Preferably, the water content is less than 10% by mass of the total amount of the ink composition. By adding water, the drying properties of the ink can be controlled, and in gravure printing in particular, the characteristic gradient areas with low ink transfer can be reproduced beautifully. Furthermore, a water content in the range of 1% to 5% by mass of the total amount of the flexible packaging lamination ink composition is particularly preferable because it results in good printability. In addition, it is also possible to reduce the amount of organic solvent components used by adding water in this way. Water may be added to the organic solvent in advance to form a mixed solvent containing water, or a specific amount of water may be added separately. The flexible packaging lamination ink composition of this embodiment can be obtained as a liquid ink composition with excellent ink dispersibility and fluidity, whether it is a one-component type that does not use a curing agent such as an isocyanate curing agent, or a two-component type that uses a curing agent.

[0115] (Method for manufacturing an ink composition for flexible packaging lamination) The ink composition for flexible packaging lamination of this embodiment can be manufactured by dissolving and / or dispersing resins, pigments, etc., in an organic solvent. Specifically, a pigment dispersion can be manufactured by dispersing pigments in an organic solvent with a polyvinyl butyral resin, and then the ink can be manufactured by blending other compounds, resins, etc., into the obtained pigment dispersion. Polyurethane resins, other resins, or dispersants may be used to disperse the pigments, but it is preferable to disperse them using polyvinyl butyral resins, etc.

[0116] The particle size distribution of pigments in a pigment dispersion can be adjusted by appropriately adjusting the size of the grinding media in the disperser, the packing rate of the grinding media, the dispersion processing time, the discharge speed of the pigment dispersion, the viscosity of the pigment dispersion, etc. Commonly used dispersers such as roller mills, ball mills, pebble mills, attritors, and sand mills can be used. If air bubbles or unexpectedly large particles are present in the ink, it is preferable to remove them by filtration or other means, as this will degrade the quality of the printed material. Conventional known filters can be used.

[0117] The viscosity of the ink composition produced by the above method is preferably in the range of 10 mPa·s or more from the viewpoint of preventing pigment sedimentation and dispersing it appropriately, and 1000 mPa·s or less from the viewpoint of workability during ink production and printing. The above viscosity is measured at 25°C using a Tokimec Type B viscometer. The viscosity of the ink composition can be adjusted by appropriately selecting the type and amount of raw materials used, for example, urethane resin (A), urethane resin (B), binder resin other than urethane resin (A) and (B) (for example, polyvinyl butyral resin), pigment, organic solvent, etc. The viscosity of the ink can also be adjusted by adjusting the particle size and particle size distribution of the pigment in the ink.

[0118] The color hues of the flexible packaging laminating ink composition in this embodiment include five process base colors—yellow, red, cyan, black, and white—depending on the type of pigment used, and three process gamut colors—red (orange), grass (green), and purple. Furthermore, transparent yellow, peony, vermilion, brown, gold, silver, pearl, and a nearly transparent medium for adjusting color density (including extender pigments as needed) are prepared as base colors. For boil retort inks, the pigment migration properties and heat resistance are appropriately selected.

[0119] (Printed Materials) The ink composition for flexible packaging lamination of this embodiment can be printed to produce printed materials. Printing can be done using known printing methods such as gravure printing and flexographic printing, but gravure printing is particularly preferred. Known cylinders such as engraved type and etching type can be used for gravure printing. The layer that forms a desired pattern using the ink composition for flexible packaging lamination of this embodiment is called the printed layer. The printed layer may be a single layer or there may be multiple printed layers. If there are multiple printed layers, the ink composition used for each printed layer may be the same, or it may be the same composition with only the pigment differing, or it may be a different composition. For example, if there are multiple printed layers, the printed material may have a first printed layer formed from a colored ink composition, a second white printed layer formed from white ink, and a third white printed layer in that order. The first printing layer can form a pattern using pigments, and the second white printing layer and the third printing layer, formed with white liquid ink, can be used as backgrounds for the pattern. If the second or third printing layer is an overprint varnish, it does not need to contain coloring agents such as pigments.

[0120] The base ink is diluted with a diluent solvent to a viscosity and concentration suitable for gravure or flexographic printing, and supplied to each printing unit, either alone or in mixtures, for printing.

[0121] (Laminated Laminate) The present disclosure may be a laminated laminate having a substrate and a printed layer on which an ink composition for flexible packaging laminate is printed on at least a portion of the surface of the substrate. The printed layer on the surface of the substrate only needs to be in direct or indirect contact with the surface of the substrate. Preferred configurations of the laminated laminate of this embodiment include, for example, the following (1) to (5): (1) Substrate / adhesive layer / printed layer / substrate (2) Substrate / adhesive layer / substrate / printed layer / adhesive layer / substrate (3) Substrate / adhesive layer / first printed layer / second printed layer / substrate (4) Substrate / adhesive layer / barrier layer / printed layer / adhesive layer / substrate (5) Substrate / printed layer / adhesive layer / substrate However, the laminated laminate of this embodiment is not limited to (1) to (5) above and may include additional substrates. If multiple substrates are included, the substrates may be the same or different. Furthermore, the substrate may be a sealable sealant film or a multilayer film containing a sealant layer made of a heat sealant, and the sealable layer is referred to as the sealant layer. In addition, multiple adhesive layers may have the same composition or different compositions. Furthermore, an anchor coat layer may be sandwiched in between to improve the adhesive strength of the adhesive layer. In addition, in the above configurations (1) to (5), a configuration in which the layer between the substrates is a laminate laminated via an adhesive layer has been illustrated. However, in another aspect of this disclosure, an extrusion laminate configuration may be used by extruding molten resin without providing an adhesive layer. In the case of extrusion lamination, it is preferable to use polyethylene or polypropylene as the extruded resin. In that case, an imine-based, butadiene-based, or isocyanate-based anchor coat layer may be provided on the printed layer and the resin may be melt-extruded onto the anchor coat layer. Furthermore, the laminate of this disclosure may have a detachable primer layer as a layer that contacts the printed layer or adhesive layer. Having a detachable primer layer facilitates the peeling of the printed layer or multiple films, improves the recyclability of the film, and enhances the quality of recycled plastics. The primer layer is preferably a film that can be detached from the substrate by, for example, treatment with an alkaline solution.A known layer that can be detached from the substrate by treatment with an alkaline solution can be used, for example, a layer that dissolves or swells in an alkaline solution and then detaches from the substrate. As long as a film that can be detached from the substrate by treatment with an alkaline solution is formed, there are no particular restrictions on the type of primer layer forming composition that forms the primer layer, but for example, compositions containing urethane resin or polyvinyl alcohol are preferred, or compositions containing resins having acidic groups are also preferred. Examples of resins having acidic groups include polyurethane resins with acid value, rosin-modified maleic acid resins and rosin-modified fumaric acid resins, and other resins having acid value; and radical copolymers such as (meth)acrylic resins, styrene-(meth)acrylic resins, styrene-(anhydride)maleic acid resins, and terpene-(anhydride)maleic acid resins, obtained by copolymerizing polymerizable monomers having acidic groups, such as polymerizable monomers having carboxyl groups, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, cinnamic acid, or their acid anhydrides; polymerizable monomers having sulfonic acid groups, such as sulfonated styrene; and other polymerizable monomers having sulfonamide groups, such as vinylbenzenesulfonamide; as well as acid-modified polyolefin resins, which can be used individually or in combination.

[0122] The primer layer-forming composition may contain, in addition to the resin described above, solvents such as organic solvents and aqueous solvents, as well as additives. Examples of additives include those similar to the auxiliary agents and acidic additives that can be added to the ink layer-forming composition described above.

[0123] The ink composition for flexible packaging lamination of this embodiment is useful for a wide variety of films, from general-purpose films to various high-performance films, as a substrate for printing. There are no particular limitations on the usable plastic films, and examples include films made of polyamide resins such as Ny6, nylon 66, and nylon 46; polyester resins such as polyethylene phthalate (PET), polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, and polybutylene naphthalate; biodegradable resins represented by polyhydroxycarboxylic acids such as polylactic acid, aliphatic polyester resins such as poly(ethylene succinate) and poly(butylene succinate); thermoplastic resins such as polyolefin resins such as polypropylene (PP) and polyethylene, polyimide resins, polyarylate resins, or mixtures thereof; various high-performance films coated with inorganic or organic barrier coating materials on the surface; and laminates thereof. Among these, films made of polyester, polyamide, polyethylene, and polypropylene can be preferably used. These films may be unstretched or stretched films, and their manufacturing method is not limited. They may be multilayer films made by co-extruding the resins of each layer, or they may be multilayer sealant films having a sealant layer on the outermost layer of the multilayer film. The thickness of the base film is also not particularly limited, but is usually in the range of 1 to 500 μm.

[0124] The above-mentioned substrate may be formed from biomass polyolefin. This biomass polyolefin refers to a polyolefin resin using plant-derived olefins as raw material monomers. These raw material monomers may include petroleum-derived monomers and do not necessarily contain 100% plant-derived monomers. Commercially available biomass polyolefins can also be used. Examples of commercially available products include SGM9450F, SLL118, SLL118 / 21, SLL218, SLL318, SLH118, SLH218, and SLH0820 from Braschem.

[0125] Furthermore, the substrate used in the laminated structure of this embodiment may be a substrate having a vapor-deposited layer made of inorganic material and / or inorganic oxide on the resin film described above. By using a substrate with such vapor-deposited layer, barrier properties can be imparted to the laminated structure of this embodiment. The vapor-deposited layer can be formed using known inorganic material or inorganic oxide by known methods, and its composition and formation method are not particularly limited. In addition, the laminated structure may have two or more vapor-deposited layers, which may have the same composition or different compositions.

[0126] As the above-mentioned vapor-deposited layer, for example, a vapor-deposited film of an inorganic substance or inorganic oxide such as silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), or yttrium (Y) can be used. Furthermore, vapor-deposited films of inorganic oxides such as silicon oxide and aluminum oxide are transparent.

[0127] The inorganic oxides mentioned above are denoted as MOx (where M represents an inorganic element), such as SiOx and AlOx. The value of x can take on the following ranges: silicon (Si) 0-2, aluminum (Al) 0-1.5, magnesium (Mg) 0-1, calcium (Ca) 0-1, potassium (K) 0-0.5, tin (Sn) 0-2, sodium (Na) 0-0.5, boron (B) 0-1.5, titanium (Ti) 0-2, lead (Pb) 0-1, zirconium (Zr) 0-2, and yttrium (Y) 0-1.5. In the above, if x = 0, it is a complete inorganic element (pure substance) and is not transparent, and if the value of x is at the upper limit of the range, it indicates that it is completely oxidized. Silicon (Si) and aluminum (Al) are preferably used as the vapor-deposited layer. For silicon (Si), an x ​​value in the range of 1.0 to 2.0 can be used, and for aluminum (Al), an x ​​value in the range of 0.5 to 1.5 can be used.

[0128] The above-mentioned vapor-deposited layer can be formed on the surface of the substrate or the like by methods such as vacuum deposition, sputtering, and ion plating (physical vapor deposition, PVD), or plasma chemical vapor deposition, thermochemical vapor deposition, and photochemical vapor deposition (chemical vapor deposition, CVD).

[0129] The thickness of the above-mentioned vapor-deposited layer is not particularly limited as long as the vapor-deposited layer alone can exhibit a certain gas barrier function. The preferred range of thickness varies depending on the type of metal or metal oxide to be deposited, but is preferably 0.05 to 70 nm, more preferably 0.1 to 70 nm, even more preferably 3 to 70 nm, and even more preferably 5 to 60 nm.

[0130] As the above-mentioned metal-deposited film, VM-CPP film, which is obtained by depositing a metal such as aluminum onto a CPP film, and VM-OPP film, which is obtained by depositing a metal such as aluminum onto an OPP film, can be used. As the above-mentioned transparent-deposited film, examples include films obtained by depositing silica or alumina onto an OPP film, PET film, nylon film, etc. Films with a coating applied to the deposited layer may also be used for purposes such as protecting the inorganic-deposited layer of silica or alumina.

[0131] Paper can also be used as the substrate. For example, high-quality paper, kraft paper, pure white roll paper, glassine paper, parchment paper, Manila cardboard, white cardboard, coated paper, art paper, imitation paper, thin paper, thick paper, polyethylene coated paper, various synthetic papers, and acid-resistant paper can be used for printing on packaging materials for cosmetics, beverages, pharmaceuticals, toys, and equipment. Furthermore, it is preferable that the printing surface of the substrate be treated with corona discharge to further improve adhesion to the substrate.

[0132] <Lamination Method> The lamination method for producing the laminated body of this embodiment is not particularly limited and includes methods such as dry lamination, wet lamination, non-solvent lamination, and extrusion lamination. In this case, the layer located between the substrates is called the adhesive layer.

[0133] Examples of adhesives used in the above dry lamination include solvent-type two-component curing adhesives. A "solvent-type" adhesive refers to a form used in the so-called dry lamination method, in which the adhesive is applied to a substrate, heated in an oven or the like to evaporate the organic solvent in the coating, and then bonded to another substrate. It includes a polyisocyanate composition, a polyol composition, and an organic solvent capable of dissolving (diluting) them.

[0134] In the above-mentioned two-component curing adhesive, considering the construction of a sustainable circular society, it is preferable to use plant-derived raw materials (biomass) as raw materials for the polyisocyanate composition or polyol composition. By appropriately using biomass, the environmental burden can be reduced. Examples of such biomass include castor oil-based polyols such as castor oil, dehydrated castor oil, hydrogenated castor oil (a hydrogenated product of castor oil), and 5 to 50 mole alkylene oxide adducts of castor oil, as well as aliphatic polybasic acids such as succinic acid, succinic anhydride, glutaric acid, adipic acid, azelaic acid, sebacic acid, and itaconic acid, and alkyl esters of these acids, dimer acids, etc.

[0135] Commercially available adhesives can also be used as the biomass-based adhesives mentioned above. Examples of commercially available adhesives that can be used include those listed by the Japan Organic Resources Association, such as DIC Dry BM (manufactured by DIC Corporation) and Takenate BM (manufactured by Mitsui Chemicals, Inc.).

[0136] The weight of the above adhesive layer after drying is 0.1 g / m². ２ ~10g / m ２ Preferably, it is 1 g / m ２ ~6g / m ２ It is more preferable that it be 2 g / m ２ ~5g / m ２ It is even more preferable that this is the case. Furthermore, the thickness of the adhesive layer is preferably 0.1 μm to 10 μm, more preferably 1 μm to 7 μm, and even more preferably 2 μm to 5 μm.

[0137] Furthermore, various adhesives can be used as the adhesive layer, but it is preferable to use a pressure-sensitive adhesive. Examples of such pressure-sensitive adhesives include rubber-based adhesives obtained by dissolving polyisobutylene rubber, butyl rubber, or mixtures thereof in an organic solvent such as benzene, toluene, xylene, or hexane; or rubber-based adhesives obtained by compounding these with tackifiers such as rosin aviethylene acid ester, terpene-phenol copolymer, or terpene-indene copolymer; or acrylic-based adhesives obtained by dissolving acrylic copolymers with a glass transition temperature of 20°C or lower, such as 2-ethylhexyl acrylate / n-butyl acrylate copolymer or 2-ethylhexyl acrylate / ethyl acrylate / methyl methacrylate copolymer, in an organic solvent.

[0138] By using materials with gas barrier properties as the adhesive or anchor coating agent described later, a laminate film with particularly excellent barrier properties can be obtained. A particularly preferred adhesive with excellent gas barrier properties is 3 g / m². ２ The oxygen barrier property of the cured coating film of the adhesive applied with (solid content) is 300 cc / m². ２ / day / atm or less, or water vapor barrier property of 120 g / m² ２ This refers to products that satisfy at least one of the following conditions: / day or less. Examples of commercially available products include the "PASLIM" series such as PASLIM VM001 and PASLIM J350X manufactured by DIC Corporation, and "MAXIEVE" manufactured by Mitsubishi Gas Chemical Company.

[0139] Furthermore, the adhesive layer may also be formed from a thermoplastic resin, and the formation method may be conventionally known methods, such as the melt extrusion lamination method or the sand lamination method. In particular, to improve the interlayer adhesion strength of the extruded laminate, it is preferable to laminate the liquid ink composition of the present invention by the extrusion lamination method or the sand lamination method. Examples of thermoplastic resins that can be used for the adhesive layer include polyethylene resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE); polypropylene resins such as propylene homopolymers, propylene-α-olefin random copolymers, and propylene-α-olefin block copolymers; norbornene polymers such as ring-opening polymers (COP) of norbornene monomers and norbornene copolymers (COC) obtained by copolymerizing norbornene monomers with olefins such as ethylene, and their hydrogenated products; cyclic polyolefin resins such as vinyl alicyclic hydrocarbon polymers and cyclic conjugated diene polymers; and ethylene Examples include polyethylene elastomers such as polyvinyl acetate copolymer (EVA) and ethylene-α-olefin copolymer, thermoplastic elastomers such as polypropylene elastomers and butene elastomers; ethylene copolymers such as ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), ethylene-acrylic acid copolymer (EAA), and ethylene-methacrylic acid copolymer (EMAA); and further, ionomers of ethylene-acrylic acid copolymer and ionomers of ethylene-methacrylic acid copolymer. In addition, to improve interlayer adhesion, acid-modified polyolefin resins obtained by modifying the above-mentioned polyolefin resins with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid can also be used. Furthermore, resins obtained by graft polymerization or copolymerization of polyolefin resins with unsaturated carboxylic acids, unsaturated carboxylic acid anhydrides, or ester monomers can also be used. These resins can be used individually or in combination of two or more types.Furthermore, it is also preferable to use a polyethylene-based resin that uses the above-mentioned biomass-derived ethylene as the monomer unit.

[0140] When laminating adhesive layers by extrusion lamination, an anchor coat layer may be provided on the surface of the layer to be laminated by applying and drying an anchor coat agent. Examples of anchor coat agents include any resin with a heat resistance temperature of 135°C or higher, such as polybutadiene resins, urethane resins, polyisocyanate / polyether polyols, polyethyleneimine, vinyl-modified resins, epoxy resins, polyester resins, alkyl titanates, etc., and anchor coat agents obtained by diluting the above adhesive with an organic solvent. Among these, polyethyleneimine-based anchor coat agents and anchor coat agents obtained by diluting the above adhesive with an organic solvent are preferably used. In addition, a silane coupling agent may be used in combination as an additive, and nitrated cotton may be used in combination to improve heat resistance.

[0141] (Packaging Material) The packaging material of this embodiment preferably consists of a laminate laminate including a printed layer formed from the above-mentioned flexible packaging lamination ink composition, and more preferably consists of a laminate laminate including the ink composition. For example, it may be a packaging material in which two laminate laminates are arranged and sealed so that their respective sealant layers are in contact with each other, or a packaging material in which a continuous (one) laminate laminate is folded and arranged and sealed so that its sealant layers are in contact with each other, or a packaging material in which the laminate laminate and a thermoplastic resin film are arranged and sealed so that the sealant layer of the laminate laminate is in contact with the thermoplastic resin film. The sealing method is not particularly limited and may be heat sealing, ultrasonic sealing, or any known method. The packaging material can be suitably used as a package. Examples of such packaging include food packaging for Western-style confectionery, snacks, bread, Japanese-style confectionery, and seasonings; medical packaging for pharmaceuticals, bandages, syringes, and other medical supplies; and packaging for sanitary products such as cleaning cloths, masks, and brushes. The printed materials, laminates, and packaging materials of this disclosure are recyclable. In particular, by making the ink composition constituting the printed layer free of chlorine-vinyl acetate copolymer resins or polyvinylidene chloride resins, corrosion of recycling equipment can be prevented, making it suitable for recycling. The method of recycling the printed materials, laminates, and packaging materials of this disclosure is not particularly limited and can be carried out using known methods and equipment.

[0142] The present invention will be described in more detail below with reference to examples, but the present invention is not limited in any way to the examples below. Hereinafter, "parts" and "%" will be on a mass basis unless otherwise specified. In the present invention, the weight-average molecular weight (polystyrene equivalent) was measured by GPC (gel permeation chromatography) using a Tosoh Corporation HLC8220 system under the following conditions. Separation column: Four Tosoh Corporation TSKgelGMHHR-N columns were used. Column temperature: 40°C. Mobile phase: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd. Flow rate: 1.0 ml / min. Sample concentration: 1.0% by weight. Sample injection volume: 100 microliters. Detector: Differential refractometer. Viscosity was measured at 25°C using a Tokimec B-type viscometer.

[0143] 1. Measurement or Evaluation Methods Used in Examples and Comparative Examples The ink compositions obtained in the examples and comparative examples described below were evaluated using the following test methods. (Base Fluidity) The viscosity of the ink compositions (liquid inks) described in the examples and comparative examples was measured using a B-type viscometer at rotation speeds of 6 rpm and 60 rpm. The TI value was obtained by dividing the viscosity measured at 6 rpm by the viscosity measured at 60 rpm. If the TI value is less than 3.0, it is usable for practical purposes. ○: TI value less than 1.5 △: TI value 1.5 or more and less than 3.0 ×: TI value 3.0 or more

[0144] (Cellophane Tape Adhesion) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate in a Zahn Cup #3 (manufactured by Rigosha) for 16 seconds (25°C). A printed material was prepared using OPP film P2161 (20 μm) manufactured by Toyobo Co., Ltd. on a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. After being left for one day, cellophane tape (12 mm wide, manufactured by Nichiban) was applied to the printed surface, and the appearance of the printed film was visually judged in the following three stages when it was rapidly peeled off. ○: The printed film did not peel off at all. △: 50-80% of the printed film remained on the film. ×: Less than 50% of the printed film remained on the film.

[0145] (Blocking Resistance) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate in a Zahn Cup #3 (manufactured by Rigosha) for 16 seconds (25°C). Using a gravure proofing machine equipped with a 35 μm gravure plate, the films were superimposed so that the printed and unprinted surfaces of a printed material made using OPP film P2161 (20 μm) manufactured by Toyobo Co., Ltd. were in contact, and the viscosity was set to 10 kgf / cm². ２ The samples were subjected to a load and left in a 40°C environment for 12 hours. After removal, the state of ink transfer to the non-printed surface was visually evaluated in three stages. ○: Good, with 0% to 20% ink transfer to the non-printed surface. △: Less than 50% transfer observed. ×: Less than 80% transfer observed.

[0146] (Extruded Laminate (PEEL) Strength) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate in a Zahn Cup #3 (manufactured by Rigosha) for 16 seconds (25°C). A printed material was then produced using OPP film P2161 (20 μm) manufactured by Toyobo Co., Ltd., on a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. A polyethyleneimine-based anchor coating agent was applied to this printed material at a concentration of 0.1 g / m². ２ After coating, molten polyethylene was laminated to a thickness of 40 μm using an extrusion laminating machine to obtain a laminated product. The laminate film was then cut to a width of 15 mm and subjected to a 90-degree peel test (measurement of PEEL strength) at a tensile speed of 50 mm / min. ◎: PEEL strength is 1.5 N / 15 mm to 2.0 N / 15 mm. ○: PEEL strength is 1.0 N / 15 mm to 1.5 N / 15 mm. △: PEEL strength is 0.5 N / 15 mm to 1.0 N / 15 mm. ×: PEEL strength is less than 0.5 N / 15 mm.

[0147] (Measurement of dry laminate strength (PET film)) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate in a Zahn cup #3 (manufactured by Rigosha) for 16 seconds (25°C), and printed onto corona-treated polyester film (hereinafter referred to as PET film: product name Ester E5102, manufactured by Toyobo Co., Ltd., thickness 12 μm) using a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm, and dried at 40 to 50°C to obtain the printed material. The obtained PET printed material was laminated with an unoriented polypropylene film (hereinafter referred to as CPP: Pyrene Film-CT P1128 30 μm manufactured by Toyobo Co., Ltd.) using an ether-based dry laminating adhesive (DIC Dry LX-401A / SP-60 (manufactured by DIC)) on a dry laminating machine (manufactured by DIC Engineering). After aging at 40°C for 3 days to obtain the laminated material, it was cut into 15 mm widths and subjected to a 90-degree peel test at a tensile speed of 300 mm / min. ○: 1.5 N / 15 mm or more to less than 3.0 N / 15 mm, sufficient strength △: 1.0 N / 15 mm or more to less than 1.5 N / 15 mm, within the practical range ×: Less than 1.0 N / 15 mm, insufficient strength

[0148] (Boil Resistance) Linear low-density polyethylene film (LLDPE film: Mitsui Chemicals Tohcello Co., Ltd. TUX-HC, 60 μm thick) was laminated onto the printed materials of Examples 1 to 11 and Comparative Examples 1 to 4 using a urethane-based dry laminating adhesive, DIC Dry LX-500 / KW-75 (DIC), with a dry laminating machine (DIC Engineering). The laminated materials were then aged at 40°C for 3 days to obtain laminated products. The obtained laminated products were made into pouches measuring 120 mm x 120 mm, and 70 g of a simulated food mixture of vinegar, salad oil, and meat sauce in a weight ratio of 1:1:1 was filled and sealed as the contents. After boiling the prepared pouches at 98°C for 60 minutes, the contents were removed and the pouches were washed with water. The pouches were then cut into 15 mm wide strips, and a T-type peel test was performed at a tensile speed of 300 mm / min to evaluate the laminate strength after boiling. Similarly, the resulting laminated material was cut into 15 mm wide strips, and a T-type peel test was performed at a tensile speed of 300 mm / min to evaluate the laminate strength before boiling.

[0149] Furthermore, in the boil resistance test, a Ny film with corona treatment applied to one side was used as the film for the printed material, and the printed material was produced by printing on the corona-treated side.

[0150] The printed material is constructed with the following layers from the Ny film side of the base material: Ny base material (F) / printing ink layer / adhesive layer (Ad) / LLDPE film. ◎: 3.5 N / 15 mm or more, sufficient strength 〇: 3.0 N / 15 mm or more to less than 3.5 N / 15 mm, within the practical range △: 2.0 N / 15 mm or more to less than 3.0 N / 15 mm, slightly insufficient strength ×: Less than 2.0 N / 15 mm, insufficient strength

[0151] Furthermore, the appearance of the resulting boiled pouches was evaluated. ○: No delamination or blistering observed at all. △: Slight delamination or blistering observed in part of the pouch. ×: Clear delamination or blistering observed throughout the pouch.

[0152] (Retort Resistance) Aluminum foil and unoriented polypropylene film (hereinafter, R-CPP: ZK-75 50 μm manufactured by Toray Synthetic Film Co., Ltd.) were laminated onto the printed materials of Examples 1 to 11 and Comparative Examples 1 to 4 using a urethane-based dry laminating adhesive, DIC Dry LX-703VL / KR-90 (manufactured by DIC), with a dry laminating machine (manufactured by DIC Engineering). The laminates were then aged at 40°C for 3 days to obtain laminated materials. The obtained laminates were made into pouches measuring 120 mm x 120 mm, and 70 g of a simulated food mixture of vinegar, salad oil, and meat sauce in a weight ratio of 1:1:1 was filled and sealed as contents. After sterilizing the prepared pouches with steam retort at 135°C for 30 minutes, the contents were removed and the pouches were washed with water. The pouches were then cut into 15 mm wide strips, and a T-type peel test was performed at a tensile speed of 300 mm / min to evaluate the laminate strength after retorting. Similarly, the resulting laminated material was cut into 15 mm wide strips, and a T-type peel test was performed at a tensile speed of 300 mm / min to evaluate the laminate strength before retorting.

[0153] Furthermore, in the retort resistance test, a biaxially oriented polyester film (PET film) with corona treatment on one side was used as the film for the printed material, and the printed material was produced by printing on the corona-treated side.

[0154] The printed material produced has the following layers from the PET film side of the base material: PET base material (F) / printing ink layer / adhesive layer (Ad1) / aluminum foil (AL) / adhesive (Ad2) / R-CPP film. Biaxially oriented polyester film (PET film: E-5100, 12 μm thick, manufactured by Toyobo Co., Ltd.) was used. The evaluation results in the table are as follows.

[0155] ◎: 3.5 N / 15 mm or more, sufficient strength 〇: 3.0 N / 15 mm or more to less than 3.5 N / 15 mm, within the practical range △: 2.0 N / 15 mm or more to less than 3.0 N / 15 mm, slightly insufficient strength ×: Less than 2.0 N / 15 mm, insufficient strength

[0156] Furthermore, the appearance of the retort-processed pouches was evaluated. ○: No delamination or blistering observed at all. △: Slight delamination or blistering observed in part of the pouch. ×: Clear delamination or blistering observed throughout the pouch.

[0157] 2. Preparation of Ink Compositions of Examples and Comparative Examples (2-1) Synthesis of Urethane Resin Component (2-1.1) Synthesis of Urethane Resin (A-1) 351.5 parts of hydrogenated ketone-aldehyde resin (TEGO® Varipuls SK, number average molecular weight 800, hydroxyl value 325 mg KOH / g, manufactured by EVONIK), 48.5 parts of isophorone diisocyanate, and 400 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain urethane resin (A-1) with a solid content of 50% and a number average molecular weight of 1700.

[0158] (2-1.2) Synthesis of urethane resin (A-2) 351.5 parts of hydrogenated ketone-aldehyde resin (TEGO® Varipuls SK, number average molecular weight 800, hydroxyl value 325 mg KOH / g, manufactured by EVONIK), 82.7 parts of isophorone diisocyanate, and 434 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-2) with a solid content of 50% and a number average molecular weight of 2300.

[0159] (2-1.3) Synthesis of urethane resin (A-3) 351.5 parts of hydrogenated ketone-aldehyde resin (TEGO® Varipuls SK, number average molecular weight 800, hydroxyl value 325 mg KOH / g, manufactured by EVONIK), 109.4 parts of isophorone diisocyanate, and 460 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-3) with a solid content of 50% and a number average molecular weight of 3000.

[0160] (2-1.4) Synthesis of urethane resin (A-4) 189.7 parts of polypropylene glycol (EXCENOL 720, number average molecular weight 700, hydroxyl value 160 mg KOH / g, manufactured by AGC Inc.), 14.7 parts of isophorone diisocyanate, and 204 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-4) with a solid content of 50% and a number average molecular weight of 1000.

[0161] (2-1.5) Synthesis of urethane resin (A-5) 189.7 parts of neopentyl glycol adipate diol (number average molecular weight 700, hydroxyl value 160 mg KOH / g), 27.9 parts of isophorone diisocyanate, and 217 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-5) with a solid content of 50% and a number average molecular weight of 1500.

[0162] (2-1.6) Synthesis of urethane resin (A-6) 189.7 parts of neopentyl glycol adipate diol (number average molecular weight 700, hydroxyl value 160 mg KOH / g), 42.9 parts of isophorone diisocyanate, and 233 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-6) with a solid content of 50% and a number average molecular weight of 3000.

[0163] (2-1.7) Synthesis of urethane resin (A-7) 111.2 parts of neopentyl glycol adipate diol (number average molecular weight 800, hydroxyl value 140 mg KOH / g), 8.6 parts of isophorone diisocyanate, and 120 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-7) with a solid content of 50% and a number average molecular weight of 1200.

[0164] (2-1.8) Synthesis of urethane resin (A-8) 52.9 parts of neopentyl glycol adipate diol (number average molecular weight 800, hydroxyl value 140 mg KOH / g), 9.7 parts of isophorone diisocyanate, and 63 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-8) with a solid content of 50% and a number average molecular weight of 2800.

[0165] (2-1.9) Synthesis of urethane resin (A-9) 185.3 parts of neopentyl glycol adipate diol (number average molecular weight 900, hydroxyl value 125 mg KOH / g), 19.0 parts of isophorone diisocyanate, and 204 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-9) with a solid content of 50% and a number average molecular weight of 1700.

[0166] (2-1.10) Synthesis of urethane resin (A-10) 132.0 parts of neopentyl glycol adipate diol (number average molecular weight 900, hydroxyl value 125 mg KOH / g), 18.6 parts of isophorone diisocyanate, and 151 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-10) with a solid content of 50% and a number average molecular weight of 2400.

[0167] (2-1.11) Synthesis of urethane resin (A-11) 113.4 parts of neopentyl glycol adipate diol (number average molecular weight 900, hydroxyl value 125 mg KOH / g), 18.2 parts of isophorone diisocyanate, and 132 parts of ethyl acetate were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube. The mixture was reacted under a nitrogen stream at 90°C for 6 hours to obtain urethane resin (A-11) with a solid content of 50% and a number average molecular weight of 3000.

[0168] (2-1.12) Synthesis of urethane resin (B-1) In a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 85 parts neopentyl glycol adipate diol (hydroxyl value: 56.1 mg KOH / g), 20 parts polyethylene glycol (hydroxyl value: 278 mg KOH / g), and 18.30 parts toluene diisocyanate were charged and reacted at 90°C for 10 hours under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 1.75% by weight. Then, 63.7 parts ethyl acetate was added to this to obtain a homogeneous solution of the urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 4.41 parts isophorone diamine, 0.10 parts di-n-butylamine, 122.5 parts ethyl acetate, and 100.3 parts isopropyl alcohol, and the mixture was stirred at 45°C for 5 hours to obtain polyurethane resin solution (B-1). The obtained polyurethane resin solution (B-1) had a resin solids concentration of 30.1% by weight, a resin solids Mw of 54,000, and a urethane bond concentration of 1.30 mmol / g.

[0169] (2-1.13) Synthesis of urethane resin (B-2) In a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 88 parts neopentyl glycol adipate diol (hydroxyl value: 22.5 mg KOH / g), 12 parts polyethylene glycol (hydroxyl value: 110 mg KOH / g), and 10.80 parts toluene diisocyanate were charged and reacted at 90°C for 10 hours under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 2.40% by weight. Then, 59.7 parts ethyl acetate was added to this to obtain a homogeneous solution of the urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 4.73 parts isophorone diamine, 0.81 parts di-n-butylamine, 116.8 parts ethyl acetate, and 95.0 parts isopropyl alcohol, and the mixture was stirred at 45°C for 5 hours to obtain polyurethane resin solution (B-2). The obtained polyurethane resin solution (B-2) had a resin solids concentration of 30.0% by weight, a resin solids Mw of 27,000, and a urethane bond concentration of 0.51 mmol / g.

[0170] (2-1.14) Synthesis of urethane resin (B-3) In a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube, 20 parts of polyester polyol consisting of propylene glycol (biomass carbon content (%): 0%) and sebaciac acid (biomass carbon content (%): 100%) (hydroxyl value: 280.5 mg KOH / g, biomass carbon content (%): approximately 73%) and neopentyl glycol (biomass carbon content (%): 0 80 parts of a polyester polyol (hydroxyl value: 56.1 mg KOH / g, biomass carbon content (%): approximately 61%) consisting of sebacic acid (biomass carbon content (%): 100%) and 25.5 parts of toluene diisocyanate were charged and reacted at 90°C for 10 hours under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 3.70% by mass. Then, 67.6 parts of ethyl acetate were added to this to obtain a homogeneous solution of the urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 9.67 parts of isophorone diamine, 0.24 parts of monoethanolamine, 137.8 parts of ethyl acetate and 110.6 parts of isopropyl alcohol, and the mixture was stirred at 45°C for 5 hours to obtain a polyurethane resin solution (B-3). The obtained polyurethane resin solution (B-3) had a resin solids concentration of 30.0% by mass, a resin solids Mw of 40,000, a biomass carbon content (%) of urethane resin (B-3) of 50%, and a urethane bond concentration of 1.33 mmol / g. Furthermore, calculated from the charging ratio, the polyester polyol composed of propylene glycol and sebaciac acid, and the polyester polyol composed of neopentyl glycol and sebaciac acid, both had a biomass-derived component ratio of 30% by mass or more in the polyester polyol. The biomass carbon content (%) of the above polyester polyol and urethane resin (B-3) was calculated by the following method. <Radiocarbon ( １４ C) Calculation of content ratio (pMC%) > The obtained measurement graphite is packed into a sample folder and accelerator mass spectrometry (AMS) is performed, and the radioactive carbon content of each sample is calculated using the above formulas (2) to (4) ( １４The content ratio (pMC%) of C) was calculated. <Calculation of biomass carbon content (%)> As shown in formula (3) above, the radioactive carbon of each sample obtained by the above method ( １４ The biomass carbon content (%) was calculated by multiplying the content ratio (pMC%) of C) by 0.93 and taking into account the effects of atmospheric nuclear tests from 1950 to the present. Note that the total biomass carbon content (%) of the urethane resin (B-3) (solids) is estimated from the weight ratio of the raw material components with known biomass carbon content (%) in the aforementioned composition, as the ratio of each component varies depending on the intended use.

[0171] (2-1.15) Synthesis example of comparative urethane resin (A-12) In a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 213.4 parts of polypropylene glycol (EXCENOL 420, number average molecular weight 400, hydroxyl value 280 mg KOH / g, manufactured by AGC Inc.), 52.8 parts of isophorone diisocyanate, and 266 parts of ethyl acetate were charged and reacted at 90°C for 6 hours under a nitrogen stream to obtain comparative urethane resin (A-12) with a solid content of 50% and a number average molecular weight of 900. (2-1.16) Comparative Example: Synthesis Example of Urethane Resin (B-4) In a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 90 parts of neopentyl glycol adipate diol (hydroxyl value: 21.2 mg KOH / g), 10 parts of polyethylene glycol (hydroxyl value: 111 mg KOH / g), and 13.79 parts of isophorone diisocyanate were charged and reacted at 90°C for 10 hours under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 2.60% by weight. Then, 61.3 parts of ethyl acetate were added to this to obtain a homogeneous solution of the urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 6.06 parts of isophorone diamine, 0.45 parts of di-n-butylamine, 121.2 parts of ethyl acetate, and 98.3 parts of isopropyl alcohol, and the mixture was stirred at 45°C for 5 hours to obtain polyurethane resin solution (B-2). The obtained polyurethane resin solution (B-2) had a resin solids concentration of 30.6% by weight, a resin solids Mw of 70,000, and a urethane bond concentration of 0.45 mmol / g.

[0172] (2-2) Preparation of Ink Composition for Laminating Flexible Packaging <Example 1> A mixture was prepared by kneading together 2.0 parts by mass of urethane resin (solids) (A-1) obtained above, 30.0 parts by mass of urethane resin (solids) (B-1), 9 parts by mass of polyvinyl butyral resin-containing solution (containing 15% by mass of polyvinyl butyral resin (solids) with a glass transition temperature (Tg) of 40°C or higher), 3 parts by mass of cellulose compound-containing solution (containing 20% ​​by mass of cellulose compound (solids) with a glass transition temperature (Tg) of 40°C or higher), 10 parts by mass of phthalocyanine blue pigment (FASTGEN Blue LA5380 manufactured by DIC Corporation), and 46 parts by mass of ethyl acetate to produce a blue printing ink composition (1) as an ink composition for laminating flexible packaging. <Examples 2-21> Blue printing ink compositions (2) to (21) were prepared as flexible packaging laminating ink compositions in the same manner as in Example 1, using the compositions and composition ratios shown in Table 1 below. The blue printing ink compositions (1) to (21) obtained in Examples 1-21 were evaluated by measuring the fluidity, adhesion, blocking resistance, extrusion lamination strength on PET film, and dry lamination strength as described above. The results are shown in Tables 1 to 3.

[0173] <Comparative Examples 1-5> Comparative blue printing ink compositions (1) to (5) were prepared by mixing the comparative polyurethane resin (A-12) obtained above, urethane resin (B-1) or (B-2), a polyvinyl butyral resin-containing solution (containing 15% by mass of polyvinyl butyral resin (solids) with a glass transition temperature (Tg) of 40°C or higher), a cellulose compound-containing solution (containing 20% ​​by mass of cellulose compound (solids) with a glass transition temperature (Tg) of 40°C or higher), a phthalocyanine blue pigment (FASTGEN Blue LA5380 manufactured by DIC Corporation), and ethyl acetate in the composition ratios shown in Table 1. The comparative blue printing ink compositions (1) to (5) obtained in Comparative Examples 1 to 5 above were evaluated by measuring the fluidity, adhesion, blocking resistance, extrusion lamination strength and dry lamination strength on PET film, boil resistance, and retort resistance as described above. The results are shown in Table 4.

[0174]

[0175]

[0176]

[0177]

[0178] From the experimental results in Tables 1 to 4 above, it was confirmed that the blue printing ink compositions of the examples could form an ink layer superior to the comparative blue printing ink composition in terms of fluidity, adhesion, blocking resistance, PEEL strength, dry lamination strength, boil resistance, and retort resistance. Furthermore, comparing, for example, Example 1 and Example 5, it was confirmed that when a urethane resin (B-1) with a relatively high urethane bond concentration was used, an ink layer with superior extrusion lamination strength (PEEL strength) and adhesion could be formed. In the ink layer of Example 1, it is thought that the good combination of urethane resin (A-1) and urethane resin (B-1) improved adhesion to the substrate due to the interaction between the polar groups on the film surface and the urethane bonds of the urethane resin component in the ink layer.

Claims

1. A laminating ink composition for flexible packaging, comprising: a urethane resin (A) having a number average molecular weight of 1,000 to 3,000, with an organic diisocyanate compound (a1) and a polyol (a2) having a number average molecular weight (Mn) of 700 to 900 as reaction raw materials (I); and a urethane resin (B) having at least an aromatic polyisocyanate compound (b1) and a polyester polyol (b2) as reaction raw materials (II).

2. The urethane resin (A) is given by the following general formula (I): (In the above general formula (I), R ３ and R ４ The flexible packaging laminating ink composition according to claim 1, having a substructure represented by (where each independently represents an aromatic group having 6 to 15 carbon atoms derived from the polyol (a2), and M represents a divalent organic group derived from the organic diisocyanate compound (a1).

3. In the general formula (I), M represents an alkylene group having 1 to 12 carbon atoms or an arylene group having 6 to 12 carbon atoms, and the alkylene group contains one or more -CH ２ The flexible packaging laminating ink composition according to claim 2, wherein the - group may be substituted with -O- or -C(=O)-.

4. The urethane resin (B) is a urethane resin having a urea bond, as described in claim 1 or 2, for use as a laminate ink composition for flexible packaging.

5. The flexible packaging laminating ink composition according to claim 1 or 2, further comprising a resin (C) having a glass transition temperature (Tg) of 40°C or higher.

6. The urethane bond concentration of the urethane resin (B) is 0.6 mmol / g or more, the ink composition for flexible packaging lamination according to claim 1 or 2.

7. The liquid ink composition according to claim 1 or 2, wherein the urethane resin (B) contains a biomass-derived component.

8. The liquid ink composition according to claim 7, wherein in the urethane resin (B), the proportion of biomass-derived components in the polyester polyol (b2) contained in the reaction raw material (II) is 30% by mass or more.

9. The flexible packaging laminating ink composition according to claim 1 or 2, wherein the ratio of urethane resin (A) to the total resin solids of the flexible packaging laminating ink composition according to claim 1 or 2 is in the range of 1 to 20% by mass.

10. The flexible packaging laminating ink composition according to claim 1 or 2, wherein the ratio of urethane resin (B) to the total resin solids of the flexible packaging laminating ink composition according to claim 1 or 2 is in the range of 10% by mass to 80% by mass.

11. A printed article obtained by printing the ink composition according to claim 1 or 2 onto a substrate.

12. A laminate or packaging comprising the printed material described in claim 11.

Images