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

Abstract

The present disclosure provides an ink composition for flexible packaging laminates which is able to form ink layers excellent in terms of flowability, adhesion, blocking resistance, peel strength, and dry laminate strength. The ink composition for flexible packaging laminates contains a urethane resin (A) having a number-average molecular weight of 1,000-3,000 and formed using, as reaction starting materials, an organic diisocyanate compound (a1) and a polyol (a2) having a number-average molecular weight (Mn) of 700-900.

Description

Ink composition for laminating flexible packaging, printed matter, laminate or packaging

[0001] The present disclosure relates to an ink composition for flexible packaging laminates, a printed matter, a laminate, or a package.

[0002] Gravure inks and flexographic inks are widely used to impart aesthetic appeal and functionality to printed substrates. When printed substrates are used as packaging materials, particularly food packaging, they are typically laminated. In this case, various printing substrates and lamination processes are used, depending on the type of contents or intended use, such as front printing (printing from the front side of a material such as a plastic film) or reverse printing (reversing the printing order of the printed image or colors). Conventionally, inks used in such lamination processes have widely used a combination of polyurethane resin and vinyl chloride-vinyl acetate copolymer (PVC) resin as a binder resin that combines excellent dispersibility and high film properties. This combination of polyurethane resin and vinyl chloride-vinyl acetate copolymer (PVC) resin is an essential ink ingredient for achieving good printability and the various physical properties required for lamination inks (adhesion to substrates, lamination strength, and boil-retort suitability).

[0003] However, in response to the trend toward building a recycling-oriented society that reduces substances that may have adverse effects on humans or the environment, as exemplified by the Sustainable Development Goals, legal regulations surrounding food packaging have become stricter worldwide. In particular, in recent years, stricter regulations have been required regarding the ingredients used in packaging and their migration into food. Furthermore, the movement toward eliminating plastic has accelerated, increasing demand for recyclable packaging. Therefore, in the development of gravure ink products, it has become necessary to design ink and packaging components using materials that are guaranteed to be safe for humans and the environment. In particular, vinyl chloride-vinyl acetate copolymer (PVC) is a substance that is of concern as a hindrance to packaging recycling for the following reasons: (a) Chlorinated resins such as vinyl chloride can corrode equipment or piping by releasing hydrogen chloride during the thermal decomposition process of recycling, generating hydrochloric acid. (b) In thermal recycling, which reuses the energy generated by incinerating waste, incineration of chlorinated resins can release environmental hormones such as dioxins. Therefore, there is a need for the development of environmentally friendly inks, such as chlorine-free PVC-free inks. Furthermore, the ink performance required for gravure inks or flexographic inks includes adhesion to films, blocking resistance to prevent printed materials from adhering to each other, abrasion resistance, heat resistance, etc. (see Patent Documents 1 and 2).

[0004] JP 2005-272585 A JP 2018-131624 A

[0005] Patent Document 1 discloses a technology for using a biomass-derived polyurethane urea resin containing biomass-derived components as an environmentally friendly ink, and describes the properties of the resin as not impairing printability during printing, and having the blocking resistance, film adhesion, solvent resistance, and plate clogging resistance of the printing coating film necessary for reverse printing, and also having good lamination properties. Patent Document 2 also discloses a technology for a gravure printing ink composition for front printing containing a cellulose derivative and a polyurethane resin, which has excellent printability and exhibits good adhesion, heat resistance, and blocking resistance to a wide range of films, despite having a solvent composition that does not contain aromatic hydrocarbon solvents. However, the technologies described in Patent Documents 1 and 2 are insufficient in blocking resistance, film adhesion, and lamination properties, and further improvements are required.

[0006] Therefore, an object of the present disclosure is to provide an ink composition for laminating flexible packaging that can form an ink layer that is excellent in fluidity, adhesion, blocking resistance, PEEL strength, and dry laminate strength.

[0007] Therefore, the present inventors conducted extensive research to solve the above problems and found that an ink layer excellent in adhesion, blocking resistance, PEEL strength, and dry laminate strength can be formed by using a urethane resin (A) made from a specified organic diisocyanate compound (a1) and a specified polyol (a2) as reaction raw materials, and have completed the present invention described in any of (1) to (12) below. Furthermore, the present disclosure mainly relates to a printing ink composition for reverse printing, which can exhibit specified ink performance without using a vinyl chloride-vinyl acetate copolymer (PVC), and is therefore also useful for reducing the environmental load.

[0008] [1] The present disclosure relates to an ink composition for a flexible packaging laminate, which contains a urethane resin (A) having a number average molecular weight of 1,000 to 3,000, and which uses 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).

[0009] [2] The urethane resin (A) is represented by the following general formula (I): (In the above general formula (I), R ３ and R ４ each independently represent 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).

[0010] [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 has one or more —CH ２ The ink composition for flexible packaging laminate according to [1] or [2], wherein the - group may be substituted with -O- or -C(=O)-.

[0011] [4] The ink composition for flexible packaging laminate according to any one of [1] to [3], further containing a urethane resin (B).

[0012] [5] The ink composition for flexible packaging laminate according to any one of [1] to [4], further comprising a resin (C) having a glass transition temperature (Tg) of 40°C or higher.

[0013] [6] The ink composition for flexible packaging laminate according to any one of [4] to [5], wherein the urethane resin (B) is a compound having at least a polyester polyol (b2) and a polyisocyanate compound (b1) as reaction raw materials (II).

[0014] [7] The liquid ink composition according to any one of [4] to [6], wherein the urethane resin (B) contains a component derived from biomass.

[0015] [8] The liquid ink composition according to any one of [4] to [7], wherein in the urethane resin (B), the proportion of biomass-derived components in the polyester polyol (b2) contained in the reactive raw material (II) is 30 mass% or more.

[0016] [9] The ink composition for flexible packaging laminate according to any one of [4] to [8], wherein the urethane bond concentration of the urethane resin (B) is 0.6 mmol / g or more.

[0017]

[10] The ink composition for flexible packaging laminate according to any one of [4] to [9], wherein the urethane resin (B) has a urea bond.

[0018]

[11] The ink composition for flexible packaging laminate according to any one of [1] to [8], wherein the ratio of the urethane resin (A) to the total resin solid content of the ink composition for flexible packaging laminate according to any one of [1] to

[10] is in the range of 1 to 20 mass%.

[0019]

[12] The ink composition for flexible packaging laminate according to any one of [1] to

[11] , wherein the ratio of the urethane resin (B) to the total resin solid content of the ink composition for flexible packaging laminate according to claim 1 or 4 is in the range of 10 to 80 mass%.

[0020]

[13] A printed matter obtained by printing the ink composition for flexible packaging laminate according to any one of [1] to

[12] on a substrate.

[0021]

[14] A laminate or package comprising the printed matter according to

[13] .

[0022] According to the present disclosure, it is possible to provide an ink composition for flexible packaging laminate that can form an ink layer that is excellent in fluidity, adhesion, blocking resistance, PEEL strength, and dry laminate strength.

[0023] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail, but the present invention is not limited to the following description and can be practiced with various modifications within the scope of the gist. Furthermore, in the present embodiment, A (numerical value) to B (numerical value) mean A or more and B or less.

[0024] [Definitions] In this specification, the term "ink composition" refers to a liquid printing ink, such as gravure ink or flexographic ink, that is applied to a printing method using a printing plate, and preferably gravure ink or flexographic ink. Furthermore, in the following description, "ink" always refers to "printing ink." In this specification, "parts" always refer to "parts by mass," "total amount of ink" refers to the total amount of ink including all volatile components such as solvents, and "(ink or resin) solids (total amount)" refers to the total amount of non-volatile components only, excluding volatile components. In this specification, the term "reactive raw materials" refers to compounds that are used to obtain a target compound through a chemical reaction such as synthesis or decomposition and that partially constitute the chemical structure of the target compound, excluding catalysts and solvents. In particular, in this specification, the term "reactive raw materials" refers to precursors for obtaining the target urethane resin (A) or urethane resin (B) through a chemical reaction. As used herein, the term "structural unit" refers to a (repeating) unit of a chemical structure formed during a reaction or polymerization; in other words, it refers to a partial structure, other than the structure of the chemical bonds involved in the reaction or polymerization, in a product compound formed through a reaction or polymerization, and is a so-called residue.

[0025] The "aromatic group" in this specification may be substituted or unsubstituted. The "aromatic group" preferably has an aromatic ring having 3 to 30 carbon atoms, not including the number of carbon atoms of the substituent, and more preferably has an aromatic ring having 4 to 26 carbon atoms. The "aromatic group" in this specification may have a hydrogen atom of the aromatic ring substituted with a substituent, for example, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom. The "aromatic group" also includes heteroaromatic groups, and the -CH in the "aromatic group" may be substituted with a substituent, for example, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom. ２- or -CH= may be substituted with -O-, -S-, or -N= so that they are not adjacent to each other. Examples of the aromatic ring include a monocyclic aromatic ring, a fused aromatic ring, and a ring assembly aromatic ring. Examples of the monocyclic aromatic ring include benzene, furan, pyrrole, thiophene, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, pyridine, pyrimidine, pyridazine, pyrazine, and triazine. Examples of the fused aromatic ring include naphthalene, anthracene, phenalene, phenanthrene, quinoline, isoquinoline, quinazoline, phthalazine, pteridine, coumarin, indole, benzimidazole, benzofuran, and acridine. Examples of the ring assembly aromatic ring include biphenyl, binaphthalene, bipyridine, bithiophene, phenylpyridine, phenylthiophene, terphenyl, diphenylthiophene, and quaterphenyl. In addition, a hydrogen atom 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 a group obtained by removing two hydrogen atoms from an "aromatic group." Examples of "aryl groups" herein include a phenyl group, a naphthyl group, a phenalenyl group, a phenanthrenyl group, an anthryl group, an azulenyl group, an indenyl group, an indanyl group, and a tetralinyl group. In addition, in the "aryl group," a hydrogen atom 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. Examples of "arylene groups" herein include divalent groups obtained by removing any one hydrogen atom from the "aryl group." Examples of "aralkyl groups" herein include a benzyl group, a diphenylmethyl group, a biphenyl group, and a naphthylmethyl group. A hydrogen atom 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. Examples of the "aralkylene group" include divalent groups obtained by removing any one hydrogen atom from the above-mentioned "aralkyl group."Examples of the "aryloxy group" herein include a phenoxy group, a naphthyloxy group, an anthryloxy group, a phenanthryloxy group, and a pyrenyloxy group. A hydrogen atom on the aromatic ring of 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. Examples of the "arylthio group" herein include arylthio groups such as a phenylthio group, a naphthylthio group, an anthrylthio group, a phenanthrylthio group, and a pyrenylthio group. A hydrogen atom on the aromatic ring of 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. The "alkyl group" in this specification may be linear, branched, or cyclic, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a tert-pentyl group, a neopentyl group, a 1,2-dimethylpropyl group, an n-hexyl group, an isohexyl group, a (n-)heptyl group, a (n-)octyl group, a (n-)nonyl group, a (n-)decyl group, a (n-)undecyl group, a (n-)dodecyl group, or a cycloalkyl group described below. The "alkylene group" is a group in which one hydrogen atom has been removed from any position of the above-mentioned alkyl group, and examples thereof include a methylene group, an ethylene group, a propylene group, an isopropylene group, an n-butylene group, an isobutylene group, a sec-butylene group, a tert-butylene group, an n-pentylene group, an isopentylene group, a tert-pentylene group, a neopentylene group, a 1,2-dimethylpropylene group, an n-hexylene group, an isohexylene group, a (n-)heptylene group, a (n-)octylene group, a (n-)nonylene group, a (n-)decylene group, a (n-)undecylene group, a (n-)dodecylene group, and a cycloalkylene group described below. As used herein, the term "cycloalkyl group" includes a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a norbornyl group, an adamantyl group, and the like.Examples of "cycloalkylene groups" include groups in which one hydrogen atom has been removed from any position of the above-mentioned 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. A 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 "alkylthio groups" in this specification include a methylthio group, an ethylthio group, a propylthio group, a butylthio group, an octylthio group, and a 2-ethylhexylthio group. As used herein, the term "alkenyl group" includes, for example, an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 2-butynyl group, a pentynyl group, a hexynyl group, a vinyl group, an allyl group, or an isopropenyl group. An "alkenylene group" is a group obtained by removing one hydrogen atom from the aforementioned alkenyl group. As used herein, the term "alkoxy group" includes, for example, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a 2-ethylhexyloxy group, an octyloxy group, or a nonyloxy group. As used herein, the term "alkylene oxide group" includes, for example, a divalent group such as an ethylene oxide group, a propylene oxide group, a butylene oxide group, or a pentylene oxide group. As used herein, the term "halogen atom" includes, for example, a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. As used herein, the term "organic group" refers to a group having 1 to 20 carbon atoms. Therefore, the above-mentioned "aromatic group," "aryl group," "arylene group," "aralkyl group," "aralkylene group," "aryloxy group," "arylthio group," "alkyl group," "cycloalkyl group," "alkylthio group," "alkenyl group," "alkenylene group," "alkoxy group," and "alkylene oxide group" are included in the "organic group." In addition, any hydrogen atom can be removed depending on the valence. For example, a trivalent alkyl group is a group obtained by removing any two hydrogen atoms from an alkyl group.

[0026] [Ink Composition for Flexible Packaging Laminate (hereinafter also referred to simply as "Ink Composition")] The present disclosure relates to an ink composition for flexible packaging laminate, which 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 whose reaction raw materials (I) are an organic diisocyanate compound (a1) and a polyol (a2) having a number average molecular weight (Mn) of 700 to 900. This allows for the formation of an ink layer with excellent adhesion, blocking resistance, PEEL strength, and dry laminate strength. The ink composition for flexible packaging laminate of this embodiment may further contain a urethane resin (B) other than the urethane resin (A) as needed. This allows for the formation of an ink layer with even better adhesion, blocking resistance, PEEL strength, and dry laminate strength.

[0027] Furthermore, the ink composition for flexible packaging laminates of this embodiment may further contain a resin (C) having a glass transition temperature (Tg) of 40°C or higher, as necessary. As described below, the resin (C) having a glass transition temperature (Tg) of 40°C or higher is preferably one or more resins 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. 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 achieved. The ink composition for flexible packaging laminates of this embodiment may further contain one or more resins selected from the group consisting of other resins, pigments, organic solvents, and additives, as necessary.

[0028] The urethane resin (A), which is an essential component of the ink composition for flexible packaging laminate of the present disclosure, and the urethane resin (B), the resin (C) having a glass transition temperature (Tg) of 40°C or higher, other resins, pigments, organic solvents, and additives, which are optional components, will be described in detail below.

[0029] (Urethane Resin (A)) The ink composition for flexible packaging laminates of this embodiment contains, as an essential component, a urethane resin (A) having a number-average molecular weight of 1,000 to 3,000. The urethane resin (A) is a compound obtained by reacting 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) of this embodiment has a structure in which a structural unit derived from the organic diisocyanate compound (a1) is chemically bonded directly or indirectly to a structural unit derived from the polyol (a2) having a number-average molecular weight (Mn) of 700 to 900. The urethane resin (A) functions as a binder resin to improve ink adhesion and can also function as a pigment dispersing resin. It is preferable that the urethane resin (A) does not contain a urea bond (—NH—C(═O)—NH—). In this specification, the term "structural unit" refers to a repeating unit of a chemical structure formed during reaction or polymerization.

[0030] In the ink composition for flexible packaging laminates of this embodiment, the content of the urethane resin (A) is preferably 1 to 20 mass% relative to the total resin solids content of the ink composition for flexible packaging laminates, more preferably 3 to 18 mass%, and even more preferably 4 to 16 mass%. By setting the content of the urethane resin (A) to 1 mass% or more, good adhesion and PEEL strength are exhibited. On the other hand, by setting the content of the urethane resin (A) to 20 mass% or less, good blocking resistance is exhibited.

[0031] Below, the constituent components of the reaction raw material (I) of the urethane resin (A) (organic diisocyanate compound (a1) and polyol (a2) having a number average molecular weight (Mn) of 700 to 900) will be explained, and then a preferred embodiment of the urethane resin (A) will be explained.

[0032] <Organic diisocyanate compound (a1)> Examples of the organic diisocyanate compound (a1) used in the urethane resin (A) of the present embodiment include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates that are commonly used in the production of general polyurethane resins. Examples of the organic diisocyanate compound (a1) include those represented by the following general formula (ii): (In the above general formula (ii), L ５ and L ６ each independently represents a single bond or an alkylene group having 1 to 5 carbon atoms; M ２ In the above general formula (ii), L represents a divalent organic group. ５ is preferably a single bond or an alkylene group having 1 to 3 carbon atoms. 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 2 to 18 carbon atoms, and even more preferably 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. The above divalent organic group is preferably 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. In addition, one or two or more non-adjacent -CH ２ - may be substituted with -O-, -COO- or -OCO-. ２ is preferably an alkylene group having 3 to 12 carbon atoms, not including the number of carbon atoms of the substituent.

[0033] Specific examples of the organic diisocyanate compound (a1) of the present embodiment include 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, methyl ... Preferred are cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dimeryl diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, m-tetramethylxylylene diisocyanate, 4,4-diphenylmethane diisocyanate, tolylene diisocyanate, bis-chloromethyl-diphenylmethane-diisocyanate, 2,6-diisocyanato-benzyl chloride, and dimer diisocyanate in which the carboxyl groups of dimer acid are converted to isocyanate groups. These diisocyanate compounds can be used alone or in combination of two or more. Among the above examples of the organic diisocyanate compound (a1), hexamethylene diisocyanate, xylylene diisocyanate, and isophorone diisocyanate are preferred, with isophorone diisocyanate being 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) relative to the total amount (100% by mass) of the reaction raw material (I) is preferably 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 5 to 25% by mass. The content of the structural unit of the organic diisocyanate compound (a1) (structural unit derived from the organic diisocyanate compound (a1), i.e., the organic diisocyanate compound (a1) residue) in this embodiment is preferably 1 to 50% by mass, more preferably 5 to 40% by mass, relative to the total urethane resin (A) (resin solids). When the content of the structural unit of the organic diisocyanate compound (a1) is 1 part by mass or more relative to 100 parts by mass of the urethane resin (A), a tough ink film and good blocking resistance are obtained. Furthermore, when the content is 40 parts by mass or less, a flexible ink film is obtained.

[0035] <Polyol (a2)> The polyol (a2) of the present embodiment preferably has a partial structure represented by the following general formula (i). (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 has at least one —CH ２ - may be replaced by -O-, -COO- or -OCO-, L １ and L ２ each independently represents a single bond or an alkylene group having 1 to 5 carbon atoms, provided that one or more —CH ２ - may be replaced by -O-, -COO- or -OCO-, L ３ each independently represents a single bond or a group represented by the following general formula (a): (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). １ The other * represents a bond chemically bonded to OH (hydroxyl group) in general formula (i). １each independently represents a mezine group (-CH=), a trivalent alicyclic group having 3 to 15 carbon atoms, or a trivalent aromatic group, and ni is the number of repeating units and represents an integer of 2 or more. Note that * in the above general formula (i) represents a bond to another atom.

[0036] In this embodiment, in the general formula (i), D １ is preferably a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 3 carbon atoms. １ is preferably an alkylene group having 1 to 3 carbon atoms, and particularly preferably a methylene group. However, if one or more —CH ２ - may be substituted with -O-, -COO- or -OCO-. ２ is preferably a single bond or an alkylene group having 1 to 3 carbon atoms, more preferably a single bond. However, if one or more —CH ２ - may be substituted with -O-, -COO- or -OCO-. ３ is preferably a single bond or a group represented by the above general formula (a). ３ is a group represented by the above general formula (a), L ４ is preferably a medin group. １ is preferably a monovalent aromatic group that is unsubstituted or has 1 to 4 hydrogen atoms substituted with a substituent, and is more preferably a phenyl group, naphthyl group, phenalenyl group, phenanthrenyl group, anthryl group, azulenyl group, indenyl group, indanyl group, or tetralinyl group that is unsubstituted or has 1 to 3 hydrogen atoms substituted with 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 １is preferably 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), examples of the trivalent organic group include groups obtained by removing any one hydrogen atom from the above examples of the "divalent organic group". In the above general formula (i), ni is preferably an integer of 2 or more and 1,000 or less, preferably an integer of 2 or more and 100 or less, preferably an integer of 2 or more and 10 or less, and more preferably an integer of 2 or more and 8 or less.

[0037] The polyol (a2) of this embodiment preferably has an aromatic ring, and more preferably has an aromatic ring in the above general formula (i). When the polyol (a2) has an aromatic ring, it is more likely to exhibit the effects of improving pigment dispersibility, PEEL strength, and dry laminate strength. Another suitable polyol (a2) is preferably a polyol having an alkylene oxide skeleton, such as polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. A preferred aspect of the polyol (a2) of this embodiment is that the polyol (a2) has a partial structure represented by the above general formula (i), and the L in the above general formula (i) ３ is a group represented by the above general formula (a), and R １ represents a monovalent aromatic group. That is, the polyol (a2) of this embodiment preferably has a partial structure represented by the following general formula (i-1). (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 has at least one —CH ２ - may be replaced by -O-, -COO- or -OCO-, L １ and L ２ each independently represents a single bond or an alkylene group having 1 to 5 carbon atoms; ４ each independently represents a mezine group (-CH=), and R １’ each independently represents a monovalent aromatic group; M １each independently represents a mezine group (-CH=), a trivalent alicyclic group having 3 to 15 carbon atoms, or a trivalent aromatic group, and ni represents the number of repeating units and is an integer of 2 or more. Note that * in the above general formula (i-1) represents a bond to another atom.

[0038] In the above general formula (i-1), R １’ is preferably a phenyl group, a naphthyl group, a phenalenyl group, a phenanthrenyl group, an anthryl group, an azulenyl group, or an indenyl group, which is unsubstituted or has one to three hydrogen atoms substituted with a substituent. Other symbols in general formula (i-1) are the same as those in general formula (i).

[0039] A particularly preferred embodiment of the polyol (a2) of this embodiment preferably has a partial structure represented by the following general formula (i-1.1). (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 has at least one —CH ２ - may be replaced by -O-, -COO- or -OCO-, R ２ are each independently an unsubstituted or substituted group R ３ represents a phenyl group, a naphthyl group, or a phenalenyl group, in which one to five hydrogen atoms may be substituted by the substituent R ３ 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 and is an integer of 2 or more. In addition, * in the above general formula (i-1.1) represents a bond to another atom.) In the above general formula (i-1.1), D １ is preferably a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 8 carbon atoms. ２ are each independently an unsubstituted or substituted group R ５ represents a phenyl group or a naphthyl group in which one or more but three hydrogen atoms may be substituted by 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.

[0040] 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 preferred from the viewpoint of a balance between adhesion to the film and blocking resistance. If the number average molecular weight of the polyol (a2) is too small, the cured urethane resin film tends to be hard, resulting in reduced adhesion to the film. On the other hand, if the number average molecular weight is too large, the cured urethane resin film tends to be brittle, resulting in reduced blocking resistance of the ink film. In this specification, the number average molecular weight and weight average molecular weight refer to values ​​measured by gel permeation chromatography (GPC) under the following conditions:

[0041] Measurement apparatus: High-speed GPC apparatus ("HLC-8220GPC" manufactured by Tosoh Corporation) Column: The following columns manufactured by Tosoh Corporation were used, connected in series: "TSKgel G5000" (7.8 mm I.D. x 30 cm) x 1, "TSKgel G4000" (7.8 mm I.D. x 30 cm) x 1, "TSKgel G3000" (7.8 mm I.D. x 30 cm) x 1, "TSKgel G2000" (7.8 mm I.D. x 30 cm) x 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% by mass) Standard sample: A calibration curve was prepared using the following standard polystyrene.

[0042] [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

[0043] The hydroxyl value of the polyol (a2) of this embodiment may be preferably 80 to 450 mgKOH / g, more preferably 100 to 400 mgKOH / g, and even more preferably 105 to 385 mgKOH / g. When the hydroxyl value of the polyol (a2) is within the above range, it is easy to control the urethane bond concentration to a predetermined value or higher, and therefore the laminate strength may be further improved.

[0044] In the reactive raw material (I) of the urethane resin (A) of this embodiment, the proportion of the polyol (a2) relative to the total amount (100% by mass) of the reactive raw material (I) is preferably 60% to 99% by mass, more preferably 65% ​​to 95% by mass. That is, the inclusion of a structural unit derived from polyol (a2) in the polyol structure of the urethane resin (A) is preferred because it can improve laminate strength. Furthermore, the inclusion of a structural unit derived from a polyol, optionally used in combination with the urethane resin (A), can improve the dispersibility and fluidity of the ink and also improve adhesion, which is preferred. In this embodiment, the content of the structural unit of polyol (a2) (structural unit derived from polyol (a2), so-called polyol (a2) residue) is preferably 60% to 99% by mass, more preferably 65 to 95% by mass, relative to the total urethane resin (A) (resin solids). When the content of the structural unit of polyol (a2) is 60% by mass or more relative to 100 parts by mass of urethane resin (A), the urethane resin (A) is guaranteed to have good solubility in ketone, ester, and alcohol-based solvents, resulting in good adhesion to high-performance barrier films. Furthermore, the ink film is easily resolubilized in the solvent, improving the tone reproducibility of printed matter. Furthermore, when the content is 99% by mass or less, the ink film has adequate flexibility, which tends to result in good blocking resistance.

[0045] (Preferred embodiment of urethane resin (A)) The urethane resin (A) of this embodiment has a number average molecular weight (Mn) of 1000 to 3000, preferably 1200 to 3000. When the number average molecular weight (Mn) of the urethane resin (A) is 1000 to 3000, this is preferred from the viewpoint of the blocking resistance of the ink composition, the strength and oil resistance of the printed film, or the gloss of the printed film. The urethane resin (A) of this embodiment is a compound represented by the following general formula (I): (In the above general formula (I), R ３ and R ４each 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 addition, * in the above general formula (I) represents a bond to another atom.) It is preferable that the urethane resin (A) has a partial structure represented by the above general formula (I), which makes it possible to form an ink layer that is superior in adhesion, blocking resistance, PEEL strength, and dry laminate strength. In the above general formula (I), R ３ and R ４ are each independently one to three hydrogen atoms that are unsubstituted or substituted by R ５ Preferably, the substituent R represents a phenyl group or a naphthyl group, which may be substituted by 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, not including the number of carbon atoms of the substituent.

[0046] (Characteristics of Urethane Resin (A)) The urethane bond concentration of the urethane resin (A) of 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 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 mathematical formula (1). [Mathematical 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), W is as follows. １ OH: weight of polyol (a2-1) １ W: hydroxyl value of polyol (a2-1) ２ OH: weight of polyol (a2-2) ２: hydroxyl value of polyol (a2-2) Wi: weight of polyol (a2-i) OHi: hydroxyl value of polyol (a2-i) S １ : weight of the solid content of the urethane resin (A) Note that in the above formula (1), polyols (a2-1), (a2-2), (a2-3), ... polyols (a2-i) are all included in the polyol (a2) having a number average molecular weight (Mn) of 700 to 900. In other words, when i types of polyols (a2) are used as the reaction raw material (I) of the urethane resin (A), the numerator of the above formula (1) is the sum of the values ​​obtained by multiplying the blend amount of each of the i types of polyols (a2) by the hydroxyl value of each polyol (a2). The denominator of the above formula (1) is S, which is the weight of the solid content of the obtained urethane resin (A). １ is multiplied by 56,100.

[0047] The urethane resin (A) of this embodiment may be composed solely of a resin having a partial structure represented by general formula (I), or may be a mixture containing a resin having a partial structure represented by general formula (I). In this embodiment, the lower limit of the content of the resin having the partial structure represented by general formula (I) relative to the entire 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. Meanwhile, the upper limit of the content of the resin having the partial structure 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 of the content of the urethane resin (A) having a partial structure represented by general formula (I) is 10% by mass to 100% by mass, 20% by mass to 95% by mass, 30% by mass to 90% by mass, and 32% by mass to 80% by mass, based on the total resin solids (100% by mass) of the urethane resin (A). When the content of the resin having a partial structure represented by general formula (I) is in the range of 10% by mass to 100% by mass, a strong ink film, good adhesion, and PEEL strength can be obtained. The above upper and lower limits can be appropriately combined. In this embodiment, the lower limit of the content of the resin having a partial structure represented by general formula (I) based on 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 the partial structure 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 the partial structure represented by general formula (I) is preferably 1% to 100% by mass, 5% to 80% by mass, and 12% to 64% by mass, relative to the total resin solids content (100% by mass) of the ink composition, in that order. The above upper and lower limits can be combined as appropriate.

[0048] (Urethane Resin (B)) The ink composition for flexible packaging laminate of this embodiment may contain a urethane resin (B) other than the urethane resin (A). Furthermore, the urethane resin (B) essentially contains a urea bond. This provides excellent boiling resistance, retort resistance, and blocking resistance. It is preferable that the urethane resin (B) has a chemical structure different from that of the urethane resin (A), and that the urethane resin (A) does not contain a urea bond. The ink composition for flexible packaging laminate of this embodiment contains both the urethane resin (A) and the urethane resin (B) having a chemical structure different from that of the urethane resin (A), thereby functioning as a binder resin to further improve the adhesion of the ink and also functioning as a pigment dispersing resin. The urethane resin (B) of this embodiment is preferably a compound obtained by reacting a polyisocyanate compound (b1) and a polyol component (e.g., including at least a polyester polyol (b2)) as reaction raw materials (II). In other words, the urethane resin (B) in this embodiment has a structure in which a structural unit derived from a polyisocyanate compound (b1) and a structural unit derived from a polyester polyol (b2) are chemically bonded directly or indirectly. As will be described later, the urethane resin (B) may use a polyester polyol (b2) and a polyether polyol (b3) as the polyol components as the reaction raw materials (II). That is, a preferred urethane resin (B) in this embodiment may be a compound in which the reaction raw materials (II) are a polyisocyanate compound (b1), a polyester polyol (b2), and a polyether polyol (b3). For convenience, the present specification distinguishes between the reaction raw materials for the urethane resin (B) and the reaction raw materials for the urethane resin (A), referring to them as the reaction raw materials (II) and the reaction raw materials for the urethane resin (A).

[0049] In the ink composition for flexible packaging laminate 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 ink composition for flexible packaging laminate. By setting the content of urethane resin (B) to 10% by mass or more, good boiling resistance, retort resistance, and blocking resistance are 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. The urethane resin (B) refers to a resin other than the urethane resin (A) that has a urethane bond.

[0050] <Polyisocyanate Compound (b1)> The reaction raw material (II) for the urethane resin (B) of this embodiment contains a polyisocyanate compound (b1). The polyisocyanate compound (b1) used for 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. Examples of the polyisocyanate compound (b1) include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates that are commonly used in the production of the above-mentioned known polyurethane resins. As the polyisocyanate compound (b1), the same isocyanate compounds as the organic diisocyanate compound (a1) can be used, for example, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene Examples of the diisocyanate include diisocyanate, lysine diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dimeryl diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, m-tetramethylxylylene diisocyanate, 4,4-diphenylmethane diisocyanate, tolylene diisocyanate, bis-chloromethyl-diphenylmethane-diisocyanate, 2,6-diisocyanato-benzyl chloride, and dimer diisocyanate in which the carboxyl groups of dimer acid are converted to isocyanate groups. These diisocyanate compounds can be used alone or in combination of two or more.

[0051] In the reactive raw material (II) of the urethane resin (B) of this embodiment, the proportion of the polyisocyanate compound (b1) relative to the total amount (100% by mass) of the reactive raw material (II) is preferably 1% by mass to 40% by mass, and more preferably 5% by mass to 30% by mass. The content of the structural unit of the polyisocyanate compound (b1) in the urethane resin (B) is preferably in the range of 1% by mass to 40% by mass, and more preferably 5% by mass to 30% by mass, relative to the urethane resin (B). When the polyisocyanate compound (b1) is 1% by mass or more, a tough ink film is obtained. When the content is 40% by mass or less, a flexible ink film is obtained.

[0052] <Polyester Polyol (b2)> The reactant (II) for the urethane resin (B) of this embodiment contains at least a polyester polyol (b2). That is, polyester polyol (b2) is essential as the polyol component of the urethane resin (B). Therefore, if necessary, the reactant (II) may further contain a polyether polyol (b3) and / or a polyol used in combination. In one aspect of the urethane resin (B) of this embodiment, when polyester polyol (b2) and polyether polyol (b3) are used as part of the reactant (II), it is preferable that the mass proportion of polyester polyol (b2) is higher than the total mass of the polyester polyol (b2) and polyether polyol (b3). In the reactant (II) for the urethane resin (B) of this embodiment, the total proportion of the polyester polyol (b2) and the polyether polyol (b3) is preferably 40% by mass to 99% by mass, more preferably 50% by mass to 95% by mass, relative to the total amount (100% by mass) of the reactant (II). In the reactive raw material (II) of the urethane resin (B) of this embodiment, the proportion of the polyester polyol (b2) relative to the total amount (100% by mass) of the reactive raw material (II) is preferably 40% by mass to 95% by mass, and more preferably 50% by mass to 95% by mass. That is, the polyol structure of the urethane resin (B) preferably contains structural units derived from the polyester polyol (b2), which can improve laminate strength. Furthermore, the polyether polyol (b3) preferably contains structural units derived from the polyether polyol (b3), which can improve the dispersibility and fluidity of the ink and also improve adhesion.

[0053] In this embodiment, the mass ratio ((b2):(b3)) of the polyester polyol (b2) to the polyether polyol (b3) in the polyol structure (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. A mass ratio of the polyester polyol (b2) to the polyether polyol (b3) in the range of 45:55 to 100:0 is preferable because it allows for the production of printed matter that is less prone to blocking. A mass ratio in the range of 55:45 to 99:1 is preferable because it allows for the production of an ink that is particularly excellent in lamination strength, adhesion, and ink dispersibility. Furthermore, in the ink composition for flexible packaging laminates of this embodiment, when a polyvinyl butyral resin is used in combination, compatibility is good so long as the mass ratio of the polyester polyol (b2) to the polyether polyol (b3) is within the range of 55:45 to 99:1, and therefore suitable storage stability and flowability can be obtained.

[0054] The polyester polyol (b2) of 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 polyester polyol (b2) can further increase laminate strength by introducing an ester group to increase cohesive energy.

[0055] As the low molecular weight polyol, various known compounds having two or more hydroxyl groups that are generally 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). Specific examples of the low molecular weight polyol include 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, and 1,4-cyclohexanedimethanol; 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2-butanediol, 1,3-butanediol, and 2-butyl-2- Glycols having a branched structure 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; glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, and sorbitol can be used.

[0056] The polycarboxylic acid or anhydride thereof may be any of various known polycarboxylic acids commonly used in the production of known polyester polyols. One or more of the polycarboxylic acids or anhydrides thereof may be used in combination. Specific examples include polycarboxylic acids having 6 or less carbon atoms and two or more carboxyl groups, such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid, and the anhydrides of these acids; aromatic dicarboxylic acids, such as phthalic acid, isophthalic acid, terephthalic acid, and the 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 the anhydrides of these acids.

[0057] Furthermore, the polyester polyol (b2) may be any of various known polyester polyols that are generally used in the production of known polyurethane resins, such as polyester polyols obtained by ring-opening polymerization of cyclic ester compounds, for example, lactones such as polycaprolactone, polyvalerolactone, and poly(β-methyl-γ-valerolactone), or one or more of these compounds may be used in combination.

[0058] 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 even more preferably in the range of more than 900 but not more than 6,000.

[0059] The content of the structural unit of polyester polyol (b2) relative to the urethane resin (B) is preferably in the range of 40% to 85% by mass, more preferably 50% to 80% by mass. When the amount of 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, resulting in good adhesion to high-performance barrier films. Furthermore, the resolubility of the ink film in these solvents is improved, resulting in improved tone reproducibility of printed matter. Furthermore, when the amount is 85 parts by mass or less, the ink film has appropriate flexibility, which tends to result in good blocking resistance.

[0060] <Polyether polyol (b3)> The reaction raw material (II) of the urethane resin (B) of this embodiment may contain a polyether polyol (b3). The polyether polyol (b3), an optional component of the reaction raw material (II), may be any of various polyether polyols commonly used in the production of known polyurethane resins, and one or more may be used in combination. Examples include polyether polyols of polymers or copolymers of methylene oxide, ethylene oxide, propylene oxide, tetrahydrofuran, and the like. Specifically, known, general-purpose polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol may be used. The inclusion of a polyether polyol significantly improves adhesion, particularly on high-performance barrier films, resulting in excellent blocking resistance and laminate strength.

[0061] 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 be hard, resulting in reduced adhesion to polyester films. If the number-average molecular weight is greater than 3500, the resulting resin film tends to be brittle, resulting in reduced blocking resistance of the ink film.

[0062] In the reactive raw material (II) of the urethane resin (B) of this embodiment, the proportion of the polyester polyol (b2) relative to the total amount (100% by mass) of the reactive raw material (II) is preferably 40% to 95% by mass, more preferably 50% to 95% by mass. When the reactive raw material (II) contains a polyether polyol (b3), the content of the structural units of the polyether polyol (b3) is preferably in the range of 1% to 40% by mass relative to the urethane resin (B). When the polyether polyol is 1 part by mass or more per 100 parts by mass of the urethane resin (B), the solubility of the urethane resin (B) in ketone, ester, and alcohol-based solvents is ensured, resulting in good adhesion to high-performance barrier films. Furthermore, the resolubility of the ink film in the solvent is improved, resulting in improved tone reproducibility of printed matter. Furthermore, when the content is 40 parts by mass or less, the ink film has appropriate flexibility, which tends to result in good blocking resistance.

[0063] The reaction raw material (I) for the urethane resin (A) and / or the reaction raw material (II) for the urethane resin (B) of this embodiment may further contain a polyol to be used in combination, if necessary. As the polyol to be used in combination as needed for the urethane resin (A) and / or (B) used in the ink composition for flexible packaging laminate of this embodiment, various known polyols generally 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, pentaerythritol, etc. Examples of suitable polyols include saturated or unsaturated low-molecular-weight polyols (1); polycarbonate polyols (2) obtained by reacting the above-mentioned low-molecular-weight polyols with, for example, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, etc.; polybutadiene glycols (3); glycols (4) obtained by adding ethylene oxide or propylene oxide to bisphenol A; and acrylic polyols (4) obtained by copolymerizing, in one molecule, one or more hydroxyethyl groups, hydroxypropyl acrylate, hydroxybutyl acrylate, etc., or their corresponding methacrylic acid derivatives, with, for example, acrylic acid, methacrylic acid, or an ester thereof.

[0064] When the combined polyol contains polyester polyol (b2) and / or polyether polyol (b3), the content of the polyester polyol (b2) and / or polyether polyol (b3) contained in the combined polyol is also included in the mass of the polyester polyol (b2) and / or polyether polyol (b3) in the polyol structure of the urethane resin (B). Furthermore, the reaction raw material (II) for the urethane resin (B) may contain an amine compound such as a chain extender. Examples of the amine compound include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, and the like, as well as amines having a hydroxyl group in the molecule, such as dialkylamines such as 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, cyclohexylamine, di-2-hydroxypropylethylenediamine, and di-n-butylamine. By including the above-mentioned amine compound in the reaction raw material (II) for the urethane resin (B), it becomes easier to introduce a urea bond into the urethane resin (B). Furthermore, the urea bond in the urethane resin (B) has a molecular structure with a low degree of freedom of rotation at the urea bond moiety, making it easier to ensure high rigidity of the entire composition. Therefore, when the urethane resin (B) of the present embodiment has both a urethane bond and a urea bond, high rigidity and elongation performance are likely to be improved.

[0065] In the urethane resin (B) of this embodiment, it is preferable that the above-mentioned reaction raw material (II) contains a raw material derived from biomass. The urethane resin (B) of this embodiment is a compound in which the reaction raw materials (II) are a polyisocyanate compound (b1), at least a polyester polyol (b2), and, if necessary, a polyether polyol (b3). In the reaction raw material (II), the biomass may be any material. Preferably, at least one or more components constituting the polyester polyol (b2) and / or the polyether polyol (b3) or their raw materials are biomass. More specifically, "at least one or more raw materials constituting the polyester polyol (b2) are biomass" means that at least a portion of the total carbon atoms constituting the polyester polyol (b2) contain carbon atoms derived from biomass. When the polyester polyol (b2) is a compound obtained by dehydration condensation or polymerization of a low molecular weight polyol and a polycarboxylic acid or an anhydride thereof, as described above, the low molecular weight polyol and / or polycarboxylic acid or an anhydride thereof is biomass (in other words, the low molecular weight polyol and / or polycarboxylic acid or anhydride thereof contain carbon atoms derived from biomass among all carbon atoms. Similarly, the expression "at least one or more components constituting the polyether polyol (b3) or their raw materials are biomass" means that at least a portion of the total carbon atoms constituting the polyether polyol (b3) contain carbon atoms derived from biomass. Note that "biomass" refers to organic resources (e.g., agricultural, forestry, and fishery products or parts thereof, rice straw, rice husks, food waste, livestock excrement, wood chips, etc.) produced from plants and animals that can be recycled into energy or materials, but excludes fossil fuels such as petroleum and coal. For example, when the polyester polyol (b2) is composed of biomass, the polycarboxylic acid or anhydride thereof that is the raw material of the polyester polyol (b2) preferably contains carbon atoms derived from the biomass.Examples of the polycarboxylic acid containing carbon atoms derived from biomass include adipic acid (e.g., adipic acid obtained using a microorganism, see, for example, WO 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 treating ricinoleic acid obtained from castor oil with alkali at high temperature, see, for example, JP 2001-511809 A), dodecanedicarboxylic acid, maleic anhydride (e.g., maleic anhydride obtained by the method of WO 2016 / 198744), and fumaric acid (e.g., fumaric acid obtained from corn cobs, etc.). For example, biomass-derived raw materials can include succinic acid (obtained by hydrogenating fumaric acid), 1,4-butanediol (obtained by hydrogenating fumaric acid), 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, phthalic acid (obtained by the methods described in WO 2014 / 043468 or JP 2019-507757 A), and anhydrides of these acids. These polybasic acids may be used alone or in combination of two or more. Various known biomass-derived alcohols may also be used as low-molecular-weight polyols. Furthermore, the polyether polyol (b3) itself or its raw material may be biomass; for example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc. can be used. To obtain a more environmentally friendly ink, it is desirable for the urethane resin (B) to have a high biomass content. For example, in the urethane resin (B), when biomass is used as the polyester polyol (b3) of the reaction raw material (II), the proportion of biomass-derived solid components in the polyester polyol (b3) is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more.For example, when the polyester polyol (b3) is a compound obtained by dehydration condensation or polymerization using a low-molecular-weight polyol derived from biomass and / or a polycarboxylic acid derived from biomass or an anhydride thereof, the total content (solid content) of the low-molecular-weight polyol residue derived from biomass and the polycarboxylic acid residue derived from biomass or an anhydride thereof in the polyester polyol (b3) is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more. The proportion of the biomass-derived solid content in the polyester polyol (b3) can be calculated from the charged amount.

[0066] The lower limit of the biomass carbon content (%) of the urethane resin (B) (solid content) of 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 this order. Meanwhile, 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 this order. The upper and lower limits can be arbitrarily combined. For example, the preferred range of the biomass carbon content (%) of the urethane resin (B) (solid content) 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, the effect of reducing the environmental impact can be achieved. The lower limit of the biomass carbon content (%) of the ink composition (solid content) for flexible packaging laminates of 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 this order. Meanwhile, 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 this order. The upper and lower limits can be arbitrarily combined. For example, the preferred range of the biomass carbon content (%) of the ink composition (solid content) for flexible packaging laminates 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 the environmental impact can be achieved. In this specification, "biomass carbon content (%)" refers to the amount of radiocarbon ( １４ The radiocarbon content (pMC%) of radioactive carbon (C) is multiplied by 0.93, which is the correction ratio, and when the correction value is 100% or more, it is considered to be 100%. １４ The content ratio (pMC%) of radiocarbon (C) indicates the carbon concentration (mass ratio) of biomass-derived components and is related to the so-called biomass blending ratio. More specifically, the radiocarbon (１４ C) Radiocarbon obtained by the measurement method ( １４ C) content ratio. １４ C) has a half-life of 5730 years and decays into nitrogen ( １４ It is known that radioactive carbon (N) is constantly produced in minute amounts on Earth by the action of cosmic rays raining down from space. １４ C) is carbon dioxide １４ CO ２ It is oxidized to carbon dioxide and dispersed into the atmosphere, then taken up by plants and animals in the food chain, and disappears according to its half-life as it circulates through the environment via the food chain. １４ C) The measurement method is that fossil fuels are radiocarbon ( １４ C), and biomass (or biological) carbon is essentially free of radioactive carbon ( １４ C) in the carbon contained in biomass (or living organisms), and １４ C) From the ratio, radiocarbon ( １４ C) content ratio (pMC%). １４ The higher the content ratio (pMC%) of radioactive carbon (C), the less fossil fuels are used, which can have an effect of reducing the environmental load. １４ The content ratio (pMC%) of radioactive carbon (C) in the total carbon atoms in the urethane resin (B) (solid content) or the ink composition for flexible packaging laminate (solid content) of this embodiment is related to an index (=biomass carbon content (%)) that indicates the blending ratio of biomass, which is a renewable, biologically derived organic resource. １４ In the present disclosure, the radioactive carbon ( C ) of the urethane resin (B) (solid content) or the ink composition for flexible packaging laminate (solid content) can be calculated by measuring the ratio of the radioactive carbon ( C ) of the urethane resin (B) (solid content) or the ink composition for flexible packaging laminate (solid content). １４ Then, the radiocarbon content (pMC%) of the urethane resin (B) (solid content) or the ink composition for flexible packaging lamination (solid content) is calculated as shown in the following mathematical formula (4). １４The biomass carbon content (%) was calculated by multiplying the radioactive carbon (pMC%) content (pMC%) by 0.93, taking into account the effects of atmospheric nuclear testing from 1950 to the present. [Formula (2)]: Radioactive carbon ( １４ C) content ratio (pMC%) = [{radioactive carbon in urethane resin (B) (solid content) ( １４ C) ÷ carbon of urethane resin (B) (solid content) ( １２ C)) / {Radiocarbon of standard material ( １４ C) / carbon of standard material ( １２ C) x 100] [Formula (3)]: Radiocarbon ( １４ C) content ratio (pMC%) = [{radioactive carbon ( １４ C) ÷ carbon of ink composition for flexible packaging lamination (solid content) ( １２ C)) / {Radiocarbon of standard material ( １４ C) / carbon of standard material ( １２ C)} × 100] (In the above formulas (2) and (3), the standard substance used was oxalic acid (SRM4990C) supplied by the National Institute of Standards and Technology as a standard substance for dating. This was converted into graphite using the same pretreatment method as the graphite used for measurement described in the Examples section below.) [Formula (4)]: Biomass carbon content (%) = Radioactive carbon ( calculated from the above formula (2) or (3) １４ C) content ratio (pMC%) x 0.93 Note that radioactive carbon ( １４ C), which produces about 1.5 times the usual amount of radioactive carbon ( １４ C) has been observed. However, it has gradually decreased over time, and the current value is around 107.5 (pMC%). Therefore, in this disclosure, as in the ASTM D6866 standard, radiocarbon ( １４The biomass carbon content (%) is defined as the value obtained by multiplying the content ratio (pMC%) of radioactive carbon (C) by 0.93 (=100 / 107.5). However, even when the method using the above formula (4) is adopted, there are cases where a value of 100% or more is calculated. Therefore, in this disclosure, as in the ASTM standard, when the value of the biomass carbon content (%) is 100% or more, it is considered to be 100%. In this embodiment, １４ The concentration of C) is measured by accelerator mass spectrometry (AMS), which combines a tandem accelerator and a mass spectrometer, to measure the isotopes of carbon atoms (specifically, １２ C. １３ C. １４ C is an example of such a method. ) is physically separated using an accelerator utilizing the difference in atomic weight, and the abundance of each isotope atom is measured. The samples to be analyzed are urethane resin (B) (solid content) or an ink composition for flexible packaging lamination (solid content), and pretreatment is required. Specifically, as described in the Examples section below, the carbon contained in these samples is oxidized and converted into carbon dioxide. The resulting carbon dioxide is then separated from water and nitrogen, reduced, and converted into graphite, which is solid carbon. The resulting graphite is used as a measurement sample, and Cs is added to the sample. ＋ The carbon ions are accelerated using a 3MV tandem accelerator, and the negative ions are converted to positive ions. １２ C ３＋ , １３ C ３＋ , １４ C ３＋ Separating the traveling orbit of １４ C ３＋ The accelerator mass spectrometry of this embodiment employs a method of measuring carbon isotopes contained in graphite obtained from a pretreated 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 analysis electromagnet. １２ C.１３ C is on the inside, the heaviest １４ C flies on the outermost side of the bend. １２ C. １３ Since the amount of C is large, it is detected as a current by a Faraday cup detector. １４ C are counted one by one by an ionization chamber type ion detector.

[0067] The hydroxyl value of the polyester polyol (b2) of this embodiment is preferably 15 mgKOH / g to 285 mgKOH / g, more preferably 18 mgKOH / g to 285 mgKOH / g, even more preferably 20 mgKOH / g to 165 mgKOH / g, and even more preferably 20 mgKOH / g to 115 mgKOH / g. When the hydroxyl value of the polyester polyol (b2) is within the above range, it is easy to control the urethane bond concentration to a predetermined value or higher, and therefore the laminate strength can be further improved. The hydroxyl value of the polyether polyol (b3) of this embodiment is preferably 15 mgKOH / g to 285 mgKOH / g, more preferably 18 mgKOH / g to 285 mgKOH / g, even more preferably 20 mgKOH / g to 165 mgKOH / g, and even more preferably 20 mgKOH / g to 115 mgKOH / g. When the hydroxyl value of the polyether polyol (b3) is within the above range, the urethane bond concentration can be easily controlled to a predetermined value or higher, and therefore, the laminate strength can be further improved.

[0068] The urethane bond concentration of the urethane resin (B) of 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 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), W is as follows: ｂ１ OH: weight of polyester polyol (b2-1) ｂ１ W: hydroxyl value of polyester polyol (b2-1) ｂ２ OH: weight of polyether polyol (b3-1) ｂ２ W: hydroxyl value of polyether polyol (b3-1) ｂ３ OH: weight of polyester polyol (b2-2) ｂ３ W: hydroxyl value of polyester polyol (b2-2) ｂ４ OH: weight of polyether polyol (b3-2) ｂ４ W: hydroxyl value of polyether polyol (b3-2) ｂ５ OH: weight of polyester polyol (b2-3) ｂ５ W: hydroxyl value of polyester polyol (b2-3) ｂ６ OH: weight of polyether polyol (b3-3) ｂ６ W: hydroxyl value of polyether polyol (b3-3) ｂｊ OH: weight of polyester polyol (b3-j) ｂｊ W: hydroxyl value of polyester polyol (b3-j) ｂｋ OH: weight of polyether polyol (b3-k) ｂｋ S: hydroxyl value of polyether polyol (b3-k) ２: weight of the solid content of the urethane resin (B) In the above formula (5), the polyester polyol (b2-1), polyester polyol (b2-2), polyester polyol (b2-3), ..., and polyester polyol (b3-j) are all included in the polyester polyol (b2). In addition, the polyether polyol (b3-1), polyether polyol (b3-2), polyether polyol (b3-3), ..., and polyether polyol (b3-k) are all included in the polyether polyol (b3). That is, when j types of polyester polyols (b2) and k types of polyether polyols (b3) are used as reaction raw materials for urethane resin (B), the numerator of the above formula (5) is the sum of the values ​​obtained by multiplying the blend amount of each of the j types of polyester polyols (b2) by the hydroxyl value of each of the polyester polyols (b2) and the sum of the values ​​obtained by multiplying the blend amount of each of the k types of polyether polyols (b3) by the hydroxyl value of each of the polyether polyols (b3). The denominator of the above formula (5) is the value obtained by multiplying S, the weight of the solid content of the obtained urethane resin (B), by 56,100.

[0069] A preferred embodiment of the ink composition for flexible packaging laminate according to this embodiment contains a urethane resin component comprising a urethane resin (A) having the 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 containing urea bonds and urethane bonds. This provides an ink composition for flexible packaging laminate that can form an ink layer with superior fluidity, adhesion, blocking resistance, PEEL strength, and dry laminate 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 achieving a urethane bond concentration of 0.6 mmol / g or more in the urethane resin (B) include (i) reducing the molecular weight of the entire polyol component used in the reaction raw material (II) of the urethane resin (B) and (ii) adjusting the hydroxyl value and compounding ratio of the entire polyol component blended in the reaction raw material (II).

[0070] (Method for Producing Urethane Resins (A) and (B)) The polyurethane resins (A) and (B) in the ink composition for flexible packaging laminates of this embodiment can be produced, for example, by a two-stage method in which a polyol compound and a diisocyanate compound are reacted in an isocyanate excess ratio to obtain a prepolymer having terminal isocyanate groups, and then the resulting prepolymer is reacted with a chain extender and / or a terminal blocking agent in a suitable solvent, or by a one-stage method in which the polyol compound, diisocyanate compound, chain extender, and / or terminal blocking agent are reacted simultaneously in a suitable solvent selected from the above. The polyol compound can be one or more selected from the group consisting of polyol (a2), polyester polyol (b2), and polyether polyol (b3) (specifically, polypropylene glycol) having a number average molecular weight (Mn) of 700 to 900, and a combination polyol added as needed. The diisocyanate compound may be one or more compounds selected from the group consisting of organic diisocyanate compounds (a1) and polyisocyanate compounds (b1). Examples of the solvent include ester-based solvents commonly used for non-toluene gravure inks, such as ethyl acetate, propyl acetate, and butyl acetate; ketone-based solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; alcohol-based solvents such as methanol, ethanol, isopropyl alcohol, and n-butanol; hydrocarbon-based solvents such as methylcyclohexane and ethylcyclohexane; and mixed solvents thereof. Among the above methods, a two-stage method is preferred to obtain a uniform urethane resin (B). Furthermore, when producing the urethane resin (B) by the two-stage method, it is preferable to react the chain extender and / or the end-capping agent so that the total amino group (equivalent ratio) is 1 / 0.9 to 1.3. If the equivalent ratio of isocyanate groups to amino groups is less than 1 / 1.3, the chain extender and / or end-capping agent may remain unreacted, causing the polyurethane resin to yellow or emitting an odor after printing.Furthermore, in recent years, from the viewpoint of the working environment, it is more preferable not to use aromatic solvents such as toluene and xylene or ketone solvents.Examples of chain extenders used in the polyurethane resin in the ink composition for flexible packaging laminates of this embodiment include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, and dicyclohexylmethane-4,4'-diamine. In addition, 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-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine, can also be used. These chain extenders can be used alone or in combination of two or more. Furthermore, monovalent active hydrogen compounds can also be used as end-blocking agents for the purpose of terminating the reaction. Examples of such compounds include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. Furthermore, when it is particularly desired to introduce a carboxyl group into the polyurethane resin, amino acids such as glycine and L-alanine can be used as reaction terminators. These end-capping agents can be used alone or in combination of two or more.

[0071] (Resin (C) having a glass transition temperature (Tg) of 40°C or higher) The ink composition for flexible packaging laminates of this embodiment may contain a resin (C) having a glass transition temperature (Tg) of 40°C or higher, if necessary. This can provide good blocking resistance, resolubility, and ink film properties. The resin (C) having 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 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 emphasis is placed on reducing environmental impact, the resin (C) having 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 emphasis is placed on dispersibility, a polyvinyl butyral resin or a vinyl chloride-vinyl acetate copolymer resin is preferred. In this embodiment, the lower limit of the content of the 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 higher, 0.3% by mass or higher, 0.5% by mass or higher, 1.7% by mass or higher, 2.2% by mass or higher, or 2.8% by mass or higher. On the other hand, the upper limit of the content of the resin (C) having a glass transition temperature (Tg) of 40°C or higher is preferably 30% by mass or lower, 28% by mass or lower, 27% by mass or lower, 26% by mass or lower, 25% by mass or lower, or 22% by mass or lower. The preferred ranges of the content of the resin (C) are 0.1% to 30% by mass, 1.7% to 27% by mass, and 2.8% to 27% by mass, in that order. A content range of the resin (C) of 0.1% to 30% by mass is preferred from the viewpoint of improving coating properties such as blocking resistance and ensuring pigment dispersibility. The above upper and lower limits can be appropriately combined. The polyvinyl butyral resin, cellulose resin, and vinyl chloride-vinyl acetate copolymer resin, which are preferred embodiments of the resin (C) having a glass transition temperature (Tg) of 40° C. or higher, will be described in detail below.

[0072] <Polyvinyl butyral-based resin> The ink composition for flexible packaging laminates of this embodiment preferably contains a polyvinyl butyral-based resin as the resin (C) having a glass transition temperature (Tg) of 40°C or higher. This polyvinyl butyral-based resin has the binding and dispersing properties of a binder resin, and because its constituent elements are only carbon, hydrogen, and oxygen atoms, it is more environmentally friendly than vinyl chloride-vinyl acetate copolymer resins. Furthermore, when the ink composition for flexible packaging laminates contains a pigment, dispersing the pigment by grinding with a polyvinyl butyral-based resin results in superior dispersion stability compared to dispersing the pigment with a polyurethane resin (A), as the appropriate group (butyral group, polyvinyl alcohol residue, or vinyl acetate residue) adsorbs to the pigment, and the bulky butyral group creates steric hindrance. As the polyvinyl butyral-based resin of this embodiment, any known resin can be used without any particular limitation. Generally, as the polyvinyl butyral-based resin, a reaction product obtained by acetalizing polyvinyl alcohol with an aldehyde compound such as butyraldehyde by a known reaction can be used. The polyvinyl butyral-based resin of this embodiment is represented by the following general formula (iii-1): (In the above general formula (iii-1), n1 and n2 each independently represent an integer of 1 or more, and R ６ represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. ６ 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 an alkyl group, an alkenyl group, an aryl group, or an aralkyl group, and may be linear, branched, or cyclic. Of these, an alkyl group is preferred. Of these, R ６ As described above, the polyvinyl butyral resin of the present embodiment is a resin obtained by reacting polyvinyl alcohol and an aldehyde compound as raw materials. ６When represented as —C(═O)H, R in the general formula (iii-1) ６ is a hydrocarbon group derived from an aldehyde compound used in synthesizing polyvinyl butyral resins.

[0073] A suitable polyvinyl butyral-based resin in this embodiment is preferably a resin having a partial structure represented by the above general formula (iii-1), a partial structure represented by the following general formula (iii-2), and a partial structure represented by the following general formula (iii-2): (In the above general formula (iii-2), n3 is independently an integer of 1 or more, and R ７ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. (In the general formula (iii-3) above, n4 is each independently an integer of 1 or more.)

[0074] In the above general formula (iii-2), R ７ preferably represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. ７ More preferred examples of the aryl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Furthermore, when the polyvinyl butyral resin of this embodiment is represented by a resin having a partial structure represented by general formula (iii-1) above, a partial structure represented by general formula (iii-2) below, and a partial structure represented by general formula (iii-3) below, the content of the partial structure represented by 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 adjusting the content of the partial structure represented by general formula (iii-2) in the polyvinyl butyral resin to fall within the above range, an ink layer having an excellent balance between fluidity and dispersibility can be obtained.

[0075] The weight-average molecular weight of the polyvinyl butyral resin of 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 curing properties can be achieved, and the coating film can have both strength and appropriate flexibility. Furthermore, polyvinyl butyral resins with a weight-average molecular weight of 5,000 to 150,000 are easily available, and the use of such polyvinyl butyral resins makes it possible to obtain an ink layer with an excellent balance of fluidity and dispersibility.

[0076] The glass transition temperature (hereinafter, sometimes referred to as Tg) of the polyvinyl butyral resin of 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 the present invention, the glass transition temperature is obtained by measurement using a differential scanning calorimeter.

[0077] The hydroxyl value of the polyvinyl butyral resin in this embodiment is preferably in the range of 10% by mass to 40% by mass, and more preferably 15% by mass to 30% by mass. By adjusting the hydroxyl group content of the polyvinyl butyral resin to fall within the above range, an ink layer with an excellent balance of fluidity and dispersibility can be obtained. The hydroxyl group content refers to the amount of the partial structure represented by general formula (iii-3) relative to the total amount of the polyvinyl butyral resin.

[0078] 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 adjusting the amount of acetyl groups in the polyvinyl butyral resin to fall within the above range, an ink layer with an excellent balance between fluidity and dispersibility can be obtained. The amount of acetyl groups refers to the amount of acetyl groups in the partial structure represented by general formula (iii-2) above, where R ７ is a methyl group, the partial structure is called an acetyl group, and the amount of the acetyl group is the content relative to the total amount of the polyvinyl butyral resin.

[0079] The content (solid content) of the polyvinyl butyral 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, based on the total resin solid content (100% by mass) of the ink composition. Adding a total of 0.1% by mass or more of the polyvinyl butyral resins tends to maintain the adhesion and transferability of the ink film, while keeping the total content 5% by mass or less can maintain the lamination strength of the ink. The lower limit of the solid content 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. The upper limit of the solid content 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.

[0080] <Cellulose-Based Resins> Examples of the cellulose-based resins include cellulose ester resins such as cellulose acetate propionate, cellulose acetate butyrate, and other cellulose ester resins; nitrocellulose (also known as soluble cellulose); hydroxyalkyl cellulose; and carboxyalkyl cellulose. The cellulose ester resin preferably has an alkyl group, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, or a hexyl group. The alkyl group may further have a substituent. Of the above, cellulose acetate propionate, cellulose acetate butyrate, and nitrocellulose are preferred, with cellulose acetate propionate and cellulose acetate butyrate being particularly preferred. The molecular weight is preferably a weight-average molecular weight of 5,000 to 200,000, more preferably 10,000 to 50,000. Furthermore, a glass transition temperature of 120°C to 180°C is more preferred. When used in combination with the polyurethane resin of the present invention, it is expected that the ink film properties such as blocking resistance and scratch resistance will be improved. Nitrocellulose (nitrocellulose) is preferably obtained by reacting natural cellulose with nitric acid to form a nitric acid ester in which three hydroxyl groups in the six-membered ring of the anhydroglucopyranose group in the natural cellulose are substituted with nitric acid groups.

[0081] The content (solid content) of the 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 solid content (100% by mass) of the ink composition. By setting the content of the cellulose-based resin in the range of 0.2 to 3.0% by mass, blocking resistance can be improved.

[0082] <Vinyl Chloride-Vinyl Acetate Copolymer Resin> The vinyl chloride-vinyl acetate copolymer resin 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. Furthermore, the vinyl chloride-vinyl acetate copolymer resin may contain units of monomers (other monomers) other than vinyl chloride monomer units and vinyl acetate monomer units, as necessary. The other monomers are not particularly limited as long as they are copolymerizable with vinyl chloride and vinyl acetate. The vinyl chloride-vinyl acetate copolymer resin preferably has a hydroxyl value of 50 mgKOH / g to 200 mgKOH / g. Furthermore, the content of the 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 the vinyl chloride monomer units is within the above range, better blocking resistance can be exhibited. The content of the vinyl acetate monomer unit is preferably 2% by mass to 30% by mass, more preferably 5% by mass to 20% by mass, based on the total amount of the vinyl chloride-vinyl acetate copolymer resin. When the content of the vinyl acetate monomer unit is within this range, the resin has excellent flexibility and adhesion.

[0083] The mass ratio of the total polyurethane resin component to the vinyl chloride-vinyl acetate copolymer resin in the ink composition for flexible packaging laminate of this embodiment (polyurethane resin component:vinyl chloride-vinyl acetate copolymer resin) in terms of solid content is preferably 60:40 to 100:0, and more preferably 70:30 to 100:0. By including a vinyl chloride-vinyl acetate copolymer resin, lamination suitability and pigment dispersibility can be improved. On the other hand, from the perspective of reducing environmental impact, it is preferable that the ink composition does not include or contains as little vinyl chloride-vinyl acetate copolymer resin as possible. Furthermore, in this embodiment, by reducing the content of vinyl chloride-vinyl acetate copolymer resin in the ink composition for flexible packaging laminate, the recyclability of flexible packaging materials using the ink can be improved. When a vinyl chloride resin such as a vinyl chloride-vinyl acetate copolymer resin is included, it can cause corrosion to recycling equipment, but by reducing the content of vinyl chloride-based monomers, corrosion of recycling equipment can be prevented.

[0084] (Preferred Aspects of the Ink Composition for Flexible Packaging Lamination) The content of all urethane resin components contained in the ink composition for flexible packaging laminate 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, based on the total resin solids content of the ink composition for flexible packaging laminate of this embodiment. The urethane bond concentration of all urethane resin components contained in the ink composition for flexible packaging laminate 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 6.0 mmol / g to 18 mmol / g. When the urethane bond concentration of all urethane resin components is 4.0 mmol / g or more, the urethane bonds of the urethane resin components in the ink layer interact with the polar groups on the film surface, improving adhesion to the substrate and tending to result in excellent laminate strength. The urethane bond concentration of all urethane resin components is calculated from the mass of the solid content of all urethane resin components and the hydroxyl value of all polyol compounds used as reaction raw materials for all urethane resin components, as in the above formulas (1) and (5). The term "all urethane resin components" refers to resins (binder resins (solid content)) contained in the ink composition for flexible packaging laminate that have urethane bonds. Therefore, the total urethane resin components essentially 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 ink composition for flexible packaging laminate within the above ranges, the dry laminate strength is particularly excellent. In the ink composition for flexible packaging laminate of this embodiment, the total content of the urethane resin (A), the urethane resin (B), the resin (C) having a glass transition temperature (Tg) of 40°C or higher, and other resins described below is preferably 70% by mass to 100% by mass, 80% by mass to 100% by mass, 90% by mass to 100% by mass, 93% by mass to 100% by mass, 95% by mass to 100% by mass, 96% by mass to 100% by mass, or 97.1% by mass to 100% by mass, relative to the total resin solids content (100% by mass) of the ink composition for flexible packaging laminate.

[0085] (Other Resins) In addition to the urethane resin (A) and the urethane resin (B) added as needed, the ink composition for flexible packaging laminates of this embodiment may contain other resins that are compatible with ink technology. These other resins may be binder resins or dispersion resins, but are preferably added as binder resins. Examples of other resins that can be used in combination include ethylene-vinyl acetate copolymer resins, vinyl acetate resins, polyamide resins, acrylic resins, polyester resins, alkyd resins, rosin-based resins, rosin-modified maleic acid resins, ketone resins, cyclized rubbers, petroleum resins, and polyurethane resins other than the urethane resins (A) and (B). Among these, it is preferable to contain at least one resin selected from polyester resins, acrylic resins, polyamide resins, and rosin-modified maleic acid resins, as this can improve blocking resistance and resolubility. Furthermore, from the perspective of reducing environmental impact, it is preferable that the ink composition of the present disclosure does not contain a chlorine-based resin. These resins can be used alone or in combination. The content of the co-used resin is preferably 0.1% by mass to 25% by mass, more preferably 2% by mass to 15% by mass, based on the total mass of the ink composition.

[0086] <Rosin-Modified Maleic Acid Resin> The rosin-modified maleic acid resin is an alkyd resin obtained by reacting a polyhydric alcohol such as glycerin, pentaerythritol, or ethylene glycol with an adduct of rosin and maleic acid obtained by Diels-Alder reaction. The acid value is determined by the blending ratio of the polyhydric alcohol reacted with the adduct of rosin and maleic acid and the degree of esterification. In addition to the polyhydric alcohol, a polybasic acid may also be used in combination to form a structure in which a long-chain alkyd resin is bonded to the rosin skeleton.

[0087] Examples of polyhydric alcohols to be reacted with the adduct of rosin and maleic acid include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, trimethylolpropane, glycerin, pentaerythritol, sorbitol, etc. Examples of polybasic acids to be used together with these polyhydric alcohols as raw materials for alkyd resins include phthalic anhydride, terephthalic acid, isophthalic acid, adipic acid, maleic acid, itaconic acid, succinic acid, sebacic acid, etc.

[0088] 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 alkyd resin, and a styrene-based monomer may be reacted with this to produce a rosin-modified styrene-maleic acid resin, which is also included in the rosin-modified maleic acid resin.

[0089] (Pigment) The pigment used in the ink composition for flexible packaging laminate of this embodiment may be either a colored pigment or a white pigment. The pigment is not particularly limited, and examples thereof include inorganic and organic pigments used in general inks, paints, and recording agents. To particularly demonstrate the excellent effect of the present invention of improving storage stability, the pigment is preferably an organic pigment. Examples of organic pigments include soluble azo-based pigments, insoluble azo-based pigments, azo-based pigments, phthalocyanine-based pigments, halogenated phthalocyanine-based pigments, anthraquinone-based pigments, anthanthrone-based pigments, dianthraquinonyl-based pigments, anthrapyrimidine-based pigments, perylene-based pigments, perinone-based pigments, quinacridone-based pigments, thioindigo-based pigments, dioxazine-based pigments, isoindolinone-based pigments, quinophthalone-based pigments, azomethine azo-based pigments, flavanthrone-based pigments, diketopyrrolopyrrole-based pigments, isoindoline-based pigments, indanthrone-based pigments, and carbon black-based pigments. Other examples include carmine 6B, Lake Red C, Permanent Red 2B, disazo yellow, pyrazolone orange, carmine FB, cromophtal yellow, cromophtal red, phthalocyanine blue, phthalocyanine green, dioxazine violet, quinacridone magenta, quinacridone red, indanthrone blue, pyrimidine yellow, thioindigo bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, and daylight fluorescent pigments. Both non-acid-treated and acid-treated pigments can be used. Examples of the organic pigment include black pigments, indigo pigments, green pigments, red pigments, purple pigments, yellow pigments, orange pigments, and brown pigments. Specific preferred examples of each organic pigment are listed below.

[0090] 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.

[0091] 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.I. Examples of pigments that can be used include C.I. Pigment Blue 64, C.I. Pigment Blue 75, C.I. Pigment Blue 79, and C.I. Pigment Blue 80.

[0092] 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.

[0093] 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. 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 of suitable pigments include C.I. Pigment Red 271, C.I. Pigment Red 272, and C.I. Pigment Red 279.

[0094] 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 of suitable pigments include C.I. Pigment Violet 38, C.I. Pigment Violet 42, C.I. Pigment Violet 50, and the like.

[0095] 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.I. Examples of pigments that can be used include C.I. Pigment Yellow 174, C.I. Pigment Yellow 180, C.I. Pigment Yellow 185, and C.I. Pigment Yellow 213.

[0096] 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, and C.I. Pigment Orange 74.

[0097] Examples of brown pigments include C.I. Pigment Brown 23, C.I. Pigment Brown 25, and C.I. Pigment Brown 26.

[0098] 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 of pigments that can be used include C.I. Pigment Red 122, C.I. Pigment Red 178, C.I. Pigment Red 149, C.I. Pigment Red 144, C.I. Pigment Red 166, purple pigments include C.I. Pigment Violet 23 and C.I. Pigment Violet 37, yellow pigments include C.I. Pigment Yellow 83, C.I. Pigment Yellow 14, C.I. Pigment Yellow 180, and C.I. Pigment Yellow 139, and orange pigments include C.I. Pigment Orange 38, C.I. Pigment Orange 13, C.I. Pigment Orange 34, and C.I. Pigment Orange 64. It is preferable to use at least one or more pigments selected from these groups.

[0099] Examples of the inorganic pigment include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, lithopone, antimony white, and gypsum. Among the inorganic pigments, titanium oxide is particularly preferred. Titanium oxide exhibits a white color and is preferred in terms of coloring power, hiding power, chemical resistance, and weather resistance. From the viewpoint of printing performance, the titanium oxide is preferably treated with silica and / or alumina.

[0100] Examples of inorganic pigments other than white include carbon black, aluminum particles, mica, bronze powder, chrome vermilion, yellow lead, cadmium yellow, cadmium red, ultramarine, Prussian blue, red iron oxide, yellow iron oxide, iron black, and zircon. Aluminum is in powder or paste form, but it is preferably used in paste form from the standpoints of handleability and safety, and whether leafing or non-leafing aluminum is used is selected appropriately from the standpoints of brightness and concentration.

[0101] The pigment is preferably present in an amount sufficient to ensure the concentration and coloring power of the ink composition, i.e., the pigment content is preferably 1% to 60% by mass, more preferably 5% to 60% by mass, relative to the total amount (100% by mass) of the ink composition for flexible packaging laminates. The solids mass ratio in the ink composition for flexible packaging laminates is preferably 10% to 90% by mass, relative to the total amount of all resin solids in the ink composition. The pigments can be used alone or in combination of two or more types.

[0102] (Additives) The ink composition for flexible packaging laminates of this embodiment preferably further contains, as necessary, one or more additives selected from the group consisting of extender pigments, pigment dispersants, leveling agents, antifoaming agents, waxes, dispersants, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, and flame retardants. In the ink composition for flexible packaging laminates of this embodiment, the content of the additives (solid content) relative to the total amount of the ink composition is preferably 0.1% by mass to 20.0% by mass.

[0103] The ink composition for flexible packaging lamination according to this embodiment may further contain a dispersant, if necessary. To stably disperse the pigment in an organic solvent, a resin alone is sufficient. However, a dispersant can also be used in combination to further stabilize the pigment. Examples of dispersants include anionic, nonionic, cationic, and amphoteric surfactants. Examples include comb-structured polymers in which polyethyleneimine is polyester-added, or alkylamine derivatives of α-olefin maleic acid polymers. Specific examples include the Solsperse series (ZENECA), the Ajisper series (Ajinomoto), and the Homogenol series (Kao). The BYK series (BYK-Chemie) and the EFKA series (EFKA) can also be used. From the viewpoint of ink storage stability, the dispersant content in the ink is preferably 0.05% by mass or more of the total mass of the ink composition, and from the viewpoint of lamination suitability, it is preferably 5% by mass or less, more preferably 0.1% to 2% by mass.

[0104] (Organic Solvent) Various organic solvents can be used as the organic solvent used in the ink composition for flexible packaging laminate of this embodiment, for example, 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, isopropanol, n-butanol and propylene glycol monomethyl ether, and these can be used alone or in a mixture 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.

[0105] The organic solvent preferably contains the ester-based organic solvent and the alcohol-based organic solvent, and the mass ratio thereof is preferably set to 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, the ink can have excellent printability and blocking resistance. The mass ratio is more preferably 2:1 to 9:1, and even more preferably 2:1 to 8:1.

[0106] The ink composition for flexible packaging laminate of this embodiment may contain water as a volatile component in addition to the organic solvent. The water content is preferably less than 10% by mass of the total ink composition. The addition of water can control the drying speed of the ink, and in gravure printing in particular, it can beautifully reproduce the gradation areas characterized by low ink transfer. Furthermore, a water content of 1% to 5% by mass of the total ink composition for flexible packaging laminate is particularly preferred because it improves printability. Furthermore, the addition of water in this manner also makes it possible to reduce the amount of organic solvent used. Water may be added to the organic solvent in advance to form a water-containing mixed solvent, or a specific amount of water may be added separately. The ink composition for flexible packaging laminate of this embodiment can be a one-component type that does not use a curing agent such as an isocyanate curing agent, or a two-component type that does use a curing agent, and can provide a liquid ink composition with excellent ink dispersibility and flowability.

[0107] (Method for producing ink composition for flexible packaging laminate) The ink composition for flexible packaging laminate of this embodiment can be produced by dissolving and / or dispersing a resin, a pigment, etc. in an organic solvent. Specifically, a pigment dispersion is produced by dispersing a pigment in an organic solvent using a polyvinyl butyral resin, and the ink can be produced by blending other compounds, resins, etc. with the resulting pigment dispersion. The pigment may be dispersed using a polyurethane resin, other resins, or a dispersant, but it is preferable to disperse the pigment using a polyvinyl butyral resin, etc.

[0108] The particle size distribution of the pigment in the pigment dispersion can be adjusted by appropriately adjusting the size of the grinding media of the disperser, the packing ratio of the grinding media, the dispersion treatment time, the discharge speed of the pigment dispersion, the viscosity of the pigment dispersion, etc. As the disperser, commonly used devices such as a roller mill, ball mill, pebble mill, attritor, sand mill, etc. can be used. If air bubbles or unexpectedly large particles are present in the ink, they are preferably removed by filtration or the like, as they will degrade the quality of the printed material. Conventional filters can be used.

[0109] 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 sedimentation of the pigment and adequately dispersing it, 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 B-type viscometer. The viscosity of the ink composition can be adjusted by appropriately selecting the types and amounts of raw materials used, such as the urethane resin (A), the urethane resin (B), binder resins other than the urethane resins (A) and (B) (e.g., polyvinyl butyral resins), pigments, organic solvents, 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.

[0110] The hues of the ink composition for flexible packaging lamination according to this embodiment include five process basic colors, yellow, crimson, indigo, 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 (containing an extender pigment as needed) for adjusting color density are prepared as base colors. For boil retort inks, the pigments are appropriately selected taking into consideration their migration properties and heat resistance.

[0111] (Printed Matter) The ink composition for flexible packaging laminate of this embodiment can be printed to produce a printed matter. Printing methods using known printing plates, such as gravure printing and flexographic printing, are possible, with gravure printing being particularly preferred. Known cylinders, such as engraved and etching types, are used for gravure printing. The layer on which a desired design is formed using the ink composition for flexible packaging laminate of this embodiment is referred to as the "printed layer." This printed layer may be a single layer, or there may be multiple printed layers. When there are multiple printed layers, the ink compositions used for each printed layer may be the same, or may be the same composition with only the pigments differing, or may be different compositions. When there are multiple printed layers, for example, a printed matter may have a first printed layer formed from a colored ink composition, a second white printed layer formed from a white ink, and a third white printed layer, in this order. The first printed layer can form a pattern using a pigment, and the second white printed layer formed with white liquid ink and the third printed layer can be used as a background for the pattern. If the second or third printed layer is an overprint varnish, it does not need to contain a colorant such as a pigment.

[0112] The base ink is diluted with a diluting solvent to a viscosity and concentration suitable for gravure printing or flexographic printing, and is supplied to each printing unit either alone or in a mixture for printing.

[0113] (Laminated Laminate) The present disclosure may be a laminated laminate having a substrate and a printed layer on at least a portion of the substrate surface, the printed layer being printed with an ink composition for flexible packaging laminates. The printed layer on the substrate surface may be in direct or indirect contact with the surface of the substrate. Preferred configurations of the laminated ... The substrate may be a sealable sealant film or a multilayer film including a sealant layer formed by a heat-sealing agent, etc., and the sealable layer is referred to as the sealant layer. The adhesive layers may have the same or different compositions. Furthermore, an anchor coat layer may be sandwiched between the adhesive layers to improve the adhesive strength. The above configurations (1) to (5) illustrate a laminate in which the layers between the substrates are laminated via an adhesive layer. However, another aspect of the present disclosure may employ an extrusion lamination configuration in which a molten resin is extruded without an adhesive layer. In the case of extrusion lamination, polyethylene or polypropylene is preferably used as the extrusion resin. In this case, an imine-based, butadiene-based, or isocyanate-based anchor coat layer may be provided on the printing layer, and the resin may be melt-extruded onto the anchor coat layer. The laminate of the present disclosure may also have a removable primer layer that contacts the printing layer or adhesive layer. The presence of a removable primer layer makes it possible to easily peel off the printed layer or multiple films, improves the recyclability of the film, and also improves the quality of the recycled plastic. The primer layer is preferably a coating that can be removed from the substrate by treatment with an alkaline solution, for example.The layer that can be detached from the substrate by treatment with an alkaline solution can be a known one, and for example, it can be dissolved or swelled by hydrolysis in the alkaline solution, and can be detached from the substrate. As long as a coating that can be detached from the substrate by treatment with an alkaline solution can be formed, the type of primer layer-forming composition that forms the primer layer is not particularly limited, but for example, a composition containing a urethane resin or polyvinyl alcohol is preferred, or a composition containing a resin having an acidic group is also preferred. Examples of the resin having an acid group include a polyurethane resin having an acid value, a resin having an acid value such as a rosin-modified maleic acid resin or a rosin-modified fumaric acid resin; a resin which is a radical copolymer such as a (meth)acrylic resin, a styrene-(meth)acrylic resin, a styrene-maleic acid (anhydride) resin, or a terpene-maleic acid (anhydride) resin, which is obtained by copolymerizing a polymerizable monomer having an acid group, such as a polymerizable monomer having a carboxyl group such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, cinnamic acid, or an acid anhydride thereof, a polymerizable monomer having a sulfonic acid group such as sulfonated styrene, or a polymerizable monomer having a sulfonamide group such as vinylbenzenesulfonamide; and an acid-modified polyolefin resin, and these may be used singly or in combination.

[0114] In addition to the resin described above, the composition for forming a primer layer may contain a solvent such as an organic solvent or an aqueous solvent, an additive, etc. Examples of the additive include the same auxiliaries and acidic additives that can be added to the composition for forming an ink layer described above.

[0115] The ink composition for flexible packaging laminates of this embodiment is useful for printing on a wide variety of substrates, from general-purpose films to various high-performance films. Usable plastic films are not particularly limited, and examples thereof include 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 typified by polyhydroxycarboxylic acids such as polylactic acid, aliphatic polyester resins such as poly(ethylene succinate) and poly(butylene succinate); films made of thermoplastic resins such as polyolefin resins such as polypropylene (PP) and polyethylene, polyimide resins, polyarylate resins, and mixtures thereof; various high-performance films coated with an inorganic or organic barrier coating material on their surfaces; and laminates thereof. Among these, films made of polyester, polyamide, polyethylene, and polypropylene are particularly preferred. These films may be unstretched or stretched films, and the manufacturing method is not limited. They may be multilayer films produced by co-extrusion of the resins of each layer, or multilayer sealant films having a sealant layer as 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.

[0116] The substrate may be formed from a biomass polyolefin. The biomass polyolefin refers to a polyolefin resin using a plant-derived olefin as a raw material monomer. The raw material monomer may contain a petroleum-derived monomer, and may not contain 100% plant-derived monomers. Commercially available biomass polyolefins may also be used. Examples of commercially available products include SGM9450F, SLL118, SLL118 / 21, SLL218, SLL318, SLH118, SLH218, and SLH0820 manufactured by Braskem.

[0117] The substrate used in the laminate of this embodiment may be a substrate having a vapor-deposited layer made of an inorganic substance and / or an inorganic oxide provided on the resin film. By using a substrate having such a vapor-deposited layer, barrier properties can be imparted to the laminate of this embodiment. The vapor-deposited layer can be formed by a known method using a known inorganic substance or inorganic oxide, and its composition and formation method are not particularly limited. The laminate may have two or more vapor-deposited films, which may have the same composition or different compositions.

[0118] The vapor-deposited layer may be, 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), yttrium (Y), etc. Vapor-deposited films of inorganic oxides such as silicon oxide and aluminum oxide are transparent.

[0119] The inorganic oxides are expressed as MOx (where M represents an inorganic element), such as SiOx and AlOx. The value of x can range from 0 to 2 for silicon (Si), 0 to 1.5 for aluminum (Al), 0 to 1.5 for magnesium (Mg), 0 to 1 for calcium (Ca), 0 to 0.5 for potassium (K), 0 to 2 for tin (Sn), 0 to 0.5 for sodium (Na), 0 to 1.5 for boron (B), 0 to 1.5 for titanium (Ti), 0 to 2 for lead (Pb), 0 to 1 for zirconium (Zr), and 0 to 1.5 for yttrium (Y). In the above, when x = 0, the material is a completely inorganic element (pure substance) and is not transparent. When the value of x is at the upper limit of the range, the material is completely oxidized. Silicon (Si) or aluminum (Al) is preferably used as the vapor deposition layer, and silicon (Si) having an x ​​value in the range of 1.0 to 2.0 and aluminum (Al) having an x ​​value in the range of 0.5 to 1.5 can be used.

[0120] The vapor deposition layer can be formed on the surface of the substrate or the like by a physical vapor deposition method (PVD method) such as vacuum deposition, sputtering, or ion plating, or a chemical vapor deposition method (CVD method) such as plasma chemical vapor deposition, thermal chemical vapor deposition, or photochemical vapor deposition.

[0121] The thickness of the vapor-deposited layer is not particularly limited as long as the vapor-deposited layer alone can exhibit a certain level of gas barrier function. The preferred thickness range varies depending on the type of metal or metal oxide to be vapor-deposited, but is preferably 0.05 to 70 nm, more preferably 0.1 to 70 nm, still more preferably 3 to 70 nm, and even more preferably 5 to 60 nm.

[0122] Examples of the metal-deposited film include a VM-CPP film obtained by depositing a metal such as aluminum on a CPP film, and a VM-OPP film obtained by depositing a metal such as aluminum on an OPP film. Examples of the transparent deposited film include films obtained by depositing silica or alumina on an OPP film, PET film, nylon film, or the like. For the purpose of protecting the inorganic deposited layer of silica or alumina, a film with a coating applied to the deposited layer may also be used.

[0123] Paper can also be used as the substrate. For example, high-quality paper used for printing on packaging materials and packages for cosmetics, beverages, pharmaceuticals, toys, equipment, etc., kraft paper, pure white roll paper, glassine paper, parchment paper, Manila cardboard, white cardboard, coated paper, art paper, imitation paper, thin paper, cardboard, polyethylene-coated paper, various synthetic papers, acid-resistant paper, etc., can be used. In addition, it is preferable to subject the printing surface of the substrate to corona discharge treatment, as this can further improve adhesion to the substrate.

[0124] <Lamination Method> The lamination method for producing the laminate of the present embodiment is not particularly limited, and examples thereof include dry lamination, wet lamination, non-solvent lamination, extrusion lamination, etc. In this case, the layer located between the substrates is referred to as an adhesive layer.

[0125] Examples of adhesives used in the dry lamination include solvent-based two-component curing adhesives, etc. A "solvent-based" adhesive refers to a form used in a so-called dry lamination method, in which the adhesive is applied to a substrate, heated in an oven or the like to volatilize the organic solvent in the coating, and then bonded to another substrate, and includes a polyisocyanate composition, a polyol composition, and an organic solvent capable of dissolving (diluting) them.

[0126] In the two-component curing adhesive, in consideration of the creation of a sustainable recycling-based society (sustainability), it is preferable to use plant-derived materials (biomass) as raw materials for the polyisocyanate composition or polyol composition. Appropriate use of biomass can reduce environmental impact. Examples of biomass include castor oil-based polyols such as castor oil, dehydrated castor oil, hydrogenated castor oil (a hydrogenated castor oil), and 5-50 mol alkylene oxide adducts of castor oil; aliphatic polybasic acids such as succinic acid, succinic anhydride, glutaric acid, adipic acid, azelaic acid, sebacic acid, and itaconic acid; alkyl esters of these acids; and dimer acids.

[0127] Commercially available adhesives using biomass may also be used, such as those listed by the Japan Organics Resources Association, including, for example, DIC Dry BM (manufactured by DIC Corporation) and Takenate BM (manufactured by Mitsui Chemicals, Inc.).

[0128] The weight of the adhesive layer after drying is 0.1 g / m ２ ~10g / m ２ It is preferable that the density is 1 g / m ２ ~6g / m ２ More preferably, it is 2 g / m ２ ~5g / m ２ 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.

[0129] Although various types of adhesives can be used for the adhesive layer, 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 organic solvents such as benzene, toluene, xylene, and hexane, or those rubber-based adhesives blended with tackifiers such as abiethylene acid rosin ester, terpene-phenol copolymer, and terpene-indene copolymer, and acrylic-based adhesives obtained by dissolving an acrylic copolymer having a glass transition temperature of 20°C or less, such as 2-ethylhexyl acrylate-n-butyl acrylate copolymer or 2-ethylhexyl acrylate-ethyl acrylate-methyl methacrylate copolymer, in an organic solvent.

[0130] When a material having gas barrier properties is used as the adhesive or the anchor coating agent described below, a laminate film having particularly excellent gas barrier properties can be obtained. ２ The oxygen barrier property of the cured coating film of the adhesive applied at (solid content) is 300 cc / m ２ / day / atm or less, or water vapor barrier property of 120 g / m ２ 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, Inc.

[0131] The adhesive layer can also be formed from a thermoplastic resin, and can be formed by a conventionally known method, such as melt extrusion lamination or sand lamination. The liquid ink composition of the present invention is preferably laminated by extrusion lamination or sand lamination, particularly to improve the interlayer adhesion strength of the extrusion laminate. 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 and hydrogenated products thereof, such as ring-opening polymers (COP) of norbornene monomers and norbornene copolymers (COC) obtained by copolymerizing norbornene monomers with olefins such as ethylene; vinyl alicyclic hydrocarbon polymers; and cyclic polyolefin resins such as cyclic conjugated diene polymers. Examples of suitable elastomers include polyethylene-based elastomers such as ethylene-vinyl acetate copolymer (EVA) and ethylene-α-olefin copolymers, polypropylene-based elastomers, and butene-based elastomers; ethylene-based 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 ionomers of ethylene-acrylic acid copolymers and ionomers of ethylene-methacrylic acid copolymers. Furthermore, in order to improve interlayer adhesion, acid-modified polyolefin-based resins obtained by modifying the above-mentioned polyolefin-based resins with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid can also be used. In addition, resins obtained by graft polymerizing or copolymerizing a polyolefin resin with an unsaturated carboxylic acid, an unsaturated carboxylic anhydride, or an ester monomer can also be used. These resins can be used alone or in combination of two or more.It is also preferable to use the polyethylene resin using the above-mentioned biomass-derived ethylene as a monomer unit.

[0132] When laminating an adhesive layer using extrusion lamination, an anchor coating layer may be formed by applying and drying an anchor coating agent to the surface of the layer to be laminated. Examples of anchor coating agents include anchor coating agents made of any resin with a heat resistance temperature of 135°C or higher, such as polybutadiene-based resins, urethane resins, polyisocyanate-polyether polyols, polyethyleneimine, vinyl-modified resins, epoxy resins, polyester resins, and alkyl titanates, as well as anchor coating agents obtained by diluting the above adhesives with organic solvents. Among these, polyethyleneimine-based anchor coating agents and anchor coating agents obtained by diluting the above adhesives with organic solvents are preferred. A silane coupling agent may also be used as an additive, and soluble nitrocellulose may also be used to enhance heat resistance.

[0133] (Packaging Material) The packaging material of this embodiment preferably comprises a laminate laminate including a printed layer formed from the ink composition for flexible packaging laminate described above, and more preferably comprises a laminate laminate including the ink composition. For example, the packaging material may be formed by arranging two laminate laminates so that their sealant layers are in contact with each other and sealing them, or by folding a continuous (single) laminate laminate so that its sealant layers are in contact with each other and sealing it, or by arranging the laminate laminate and a thermoplastic resin film so that the sealant layer of the laminate laminate is in contact with the thermoplastic resin film and sealing it. The sealing method is not particularly limited, and may be heat sealing or ultrasonic sealing, or any known method. The packaging material can be suitably used as a package. Examples of such packaging include packaging for food products such as Western confectionery, snacks, bread, Japanese sweets, and seasonings; medical packaging for medicines, bandages, and syringes; and packaging for hygiene products such as dustcloths, masks, and brushes. The printed matter, laminate, and packaging material of the present disclosure are recyclable. In particular, by configuring the ink composition constituting the printed layer to not contain a chlorinated vinyl resin such as a vinyl chloride-vinyl acetate copolymer resin or a polyvinylidene chloride resin, corrosion of recycling equipment can be prevented, making them suitable for recyclability. The recycling method for the printed matter, laminate, and packaging material of the present disclosure is not particularly limited, and can be carried out using known methods and equipment.

[0134] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Hereinafter, "parts" and "%" are based on mass unless otherwise specified. Measurement of weight-average molecular weight (polystyrene equivalent) by GPC (gel permeation chromatography) in the present invention was carried out using an HLC8220 system manufactured by Tosoh Corporation under the following conditions: Separation column: Four TSKgel GMHHR-N columns manufactured by Tosoh Corporation. Column temperature: 40°C. Mobile phase: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd. Flow rate: 1.0 ml / min. Sample concentration: 1.0 wt%. Sample injection volume: 100 microliters. Detector: Differential refractometer. Viscosity was measured at 25°C using a B-type viscometer manufactured by Tokimec Inc.

[0135] 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 Brookfield viscometer at rotation speeds of 6 rpm and 60 rpm. The TI value was calculated by dividing the viscosity measured at 6 rpm by the viscosity measured at 60 rpm. If the TI value is less than 3.0, the ink is usable for practical use. ○: TI value less than 1.5 △: TI value 1.5 or more but less than 3.0 ×: TI value 3.0 or more

[0136] (Cellophane tape adhesion) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate to 16 seconds (25°C) using a Zahn cup #3 (manufactured by Rigo Co., Ltd.), and prints were produced using OPP film P2161 (20 μm) manufactured by Toyobo Co., Ltd., using a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. After leaving the prints for one day, cellophane tape (manufactured by Nichiban, 12 mm wide) was applied to the printed surface, which was then quickly peeled off and the appearance of the printed film was visually evaluated on the following three-point scale. ○: The printed film did not peel off at all. Δ: 50 to 80% of the printed film remained on the film. ×: Less than 50% of the printed film remained on the film.

[0137] (Blocking Resistance) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate to 16 seconds (25°C) using a Zahn cup #3 (manufactured by Rigo Co., Ltd.), and the ink compositions were printed using OPP film P2161 (20 μm) manufactured by Toyobo Co., Ltd., with the printed surface and non-printed surface of the film being in contact with each other using a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. ２ After the test pieces were removed, the state of ink transfer to the non-printed side was visually evaluated using a three-point scale. ○: Good, with 0% to 20% of the ink transferred to the non-printed side. △: Transfer of less than 50% was observed. ×: Transfer of less than 80% was observed.

[0138] (Extrusion Laminate (PEEL) Strength) The viscosity of the ink compositions described in the Examples and Comparative Examples was adjusted with ethyl acetate to 16 seconds (25°C) using a Zahn cup #3 (manufactured by Rigo Co., Ltd.), and a print was produced using an OPP film P2161 (20 μm) manufactured by Toyobo Co., Ltd., using 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 print at a concentration of 0.1 g / m. ２ After coating, molten polyethylene was laminated to a thickness of 40 μm using an extrusion laminator to obtain a laminated product, which was then cut into 15 mm wide pieces and subjected to a 90-degree peel test (measurement of PEEL strength) at a pulling rate 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.

[0139] (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 to 16 seconds (25°C) using a Zahn cup #3 (manufactured by Rigo Co., Ltd.), and printed on a corona-treated polyester film (hereinafter referred to as PET film: manufactured by Toyobo Co., Ltd., trade name: Ester E5102, 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 a print. The obtained PET print was laminated with a non-oriented polypropylene film (hereinafter referred to as CPP: Pylen Film-CT P1128 30 μm, manufactured by Toyobo Co., Ltd.) using an ether-based dry laminating adhesive (Dicdry LX-401A / SP-60, manufactured by DIC Engineering) in a dry laminating machine (manufactured by DIC Engineering), and aged at 40°C for 3 days to obtain a laminate, which was then cut into a width of 15 mm and subjected to a 90-degree peel test at a pulling rate of 300 mm / min.

[0140] 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) Into a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, 351.5 parts of a hydrogenated ketone-aldehyde resin (TEGO (registered trademark) Varipuls SK, number average molecular weight 800, hydroxyl value 325 mg KOH / g, manufactured by EVONIK Corporation), 48.5 parts of isophorone diisocyanate, and 400 parts of ethyl acetate were charged, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-1) with a solids content of 50% and a number average molecular weight of 1,700.

[0141] (2-1.2) Synthesis of Urethane Resin (A-2) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 351.5 parts of a hydrogenated ketone-aldehyde resin (TEGO (registered trademark) Varipuls SK, number average molecular weight 800, hydroxyl value 325 mg KOH / g, manufactured by EVONIK Corporation), 82.7 parts of isophorone diisocyanate, and 434 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-2) with a solids content of 50% and a number average molecular weight of 2,300.

[0142] (2-1.3) Synthesis of Urethane Resin (A-3) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 351.5 parts of a hydrogenated ketone-aldehyde resin (TEGO (registered trademark) Varipuls SK, number average molecular weight 800, hydroxyl value 325 mg KOH / g, manufactured by EVONIK Corporation), 109.4 parts of isophorone diisocyanate, and 460 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-3) with a solids content of 50% and a number average molecular weight of 3,000.

[0143] (2-1.4) Synthesis of Urethane Resin (A-4) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 189.7 parts of polypropylene glycol (EXCENOL720, number average molecular weight 700, hydroxyl value 160 mgKOH / g, manufactured by AGC Inc.), 14.7 parts of isophorone diisocyanate, and 204 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-4) having a solids content of 50% and a number average molecular weight of 1,000.

[0144] (2-1.5) Synthesis of Urethane Resin (A-5) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 189.7 parts of neopentyl glycol adipate diol (number average molecular weight 700, hydroxyl value 160 mgKOH / g), 27.9 parts of isophorone diisocyanate, and 217 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-5) with a solids content of 50% and a number average molecular weight of 1,500.

[0145] (2-1.6) Synthesis of Urethane Resin (A-6) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 189.7 parts of neopentyl glycol adipate diol (number average molecular weight 700, hydroxyl value 160 mgKOH / g), 42.9 parts of isophorone diisocyanate, and 233 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-6) having a solids content of 50% and a number average molecular weight of 3,000.

[0146] (2-1.7) Synthesis of Urethane Resin (A-7) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 111.2 parts of neopentyl glycol adipate diol (number average molecular weight 800, hydroxyl value 140 mgKOH / g), 8.6 parts of isophorone diisocyanate, and 120 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-7) having a solids content of 50% and a number average molecular weight of 1,200.

[0147] (2-1.8) Synthesis of Urethane Resin (A-8) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 52.9 parts of neopentyl glycol adipate diol (number average molecular weight 800, hydroxyl value 140 mgKOH / g), 9.7 parts of isophorone diisocyanate, and 63 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-8) with a solids content of 50% and a number average molecular weight of 2,800.

[0148] (2-1.9) Synthesis of Urethane Resin (A-9) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 185.3 parts of neopentyl glycol adipate diol (number average molecular weight 900, hydroxyl value 125 mgKOH / g), 19.0 parts of isophorone diisocyanate, and 204 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-9) with a solids content of 50% and a number average molecular weight of 1,700.

[0149] (2-1.10) Synthesis of Urethane Resin (A-10) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 132.0 parts of neopentyl glycol adipate diol (number average molecular weight 900, hydroxyl value 125 mgKOH / g), 18.6 parts of isophorone diisocyanate, and 151 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-10) with a solids content of 50% and a number average molecular weight of 2,400.

[0150] (2-1.11) Synthesis of Urethane Resin (A-11) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 113.4 parts of neopentyl glycol adipate diol (number average molecular weight 900, hydroxyl value 125 mgKOH / g), 18.2 parts of isophorone diisocyanate, and 132 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a urethane resin (A-11) having a solids content of 50% and a number average molecular weight of 3,000.

[0151] (2-1.12) Synthesis of urethane resin (B-1) A four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube was charged with 80 parts of neopentyl glycol adipate diol (hydroxyl value: 56.6 mg KOH / g) and 20 parts of polyethylene glycol (hydroxyl value: 278 mg KOH / g) and 29.68 parts of isophorone diisocyanate, and the mixture was reacted for 10 hours at 90 ° C. under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 2.84 wt%, to which 69.8 parts of ethyl acetate was added to obtain a homogeneous solution of urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture of 7.97 parts of isophorone diamine, 0.11 parts of di-n-butylamine, 139.1 parts of ethyl acetate, and 112.5 parts of isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours to obtain a polyurethane resin solution (B-1). The resulting polyurethane resin solution (B-1) had a resin solid concentration of 30.4% by weight, a Mw of the resin solid content of 54,000, and a urethane bond concentration of 1.31 mmol / g.

[0152] (2-1.13) Synthesis of urethane resin (B-2) A four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube was charged with 90 parts neopentyl glycol adipate diol (hydroxyl value: 21.2 mg KOH / g) and 10 parts polyethylene glycol (hydroxyl value: 111 mg KOH / g) and 13.79 parts isophorone diisocyanate, and the mixture was reacted for 10 hours at 90 ° C. under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 2.60 wt%, to which 61.3 parts of ethyl acetate was added to obtain a homogeneous solution of urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture of 6.06 parts isophorone diamine, 0.45 parts di-n-butylamine, 121.2 parts ethyl acetate, and 98.3 parts isopropyl alcohol, and the mixture was stirred and reacted at 45 ° C. for 5 hours to obtain a polyurethane resin solution (B-2). The resulting polyurethane resin solution (B-2) had a resin solid concentration of 30.6% by weight, a Mw of the resin solid content of 70,000, and a urethane bond concentration of 0.45 mmol / g.

[0153] (2-1.14) Synthesis of urethane resin (B-3) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 20 parts of a polyester polyol (hydroxyl value: 280.5 mg KOH / g, biomass carbon content (%): approximately 73%) consisting of propylene glycol (biomass carbon content (%): 0%) and sebacic acid (biomass carbon content (%): 100%), 80 parts of a polyester polyol (hydroxyl value: 56.1 mg KOH / g, biomass carbon content (%): approximately 61%) consisting of neopentyl glycol (biomass carbon content (%): 0%) and sebacic acid (biomass carbon content (%): 100%), and 31.9 parts of isophorone diisocyanate, and the mixture was reacted at 90°C for 10 hours under a nitrogen stream to produce a urethane prepolymer with an isocyanate group content of 3.42% by mass. To this was added 71.0 parts of ethyl acetate to form a homogeneous solution of the urethane prepolymer. Next, the urethane prepolymer solution was added to a mixture consisting of 9.79 parts of isophorone diamine, 0.24 parts of monoethanolamine, 144.8 parts of ethyl acetate, and 116.2 parts of isopropyl alcohol, and the mixture was stirred at 45 ° C. for 5 hours to produce a polyurethane resin solution (B-3). The resulting polyurethane resin solution (B-3) had a resin solids concentration of 30.0 mass%, a resin solids Mw of 69,000, and a biomass carbon content (%) of urethane resin (B-3) of 50%, and a urethane bond concentration of 1.3 mmol / g. Calculations based on the charge ratios showed that the polyester polyols composed of propylene glycol and sebacic acid and the polyester polyols composed of neopentyl glycol and sebacic acid all had a biomass-derived component ratio of 30 mass% or more in the polyester polyol. The biomass carbon content (%) of the polyester polyol and urethane resin (B-3) was calculated using the following method. <Radiocarbon ( １４ The obtained graphite for measurement was filled into a sample holder, and accelerator mass spectrometry (AMS) was performed. The radiocarbon ( １４The radiocarbon (pMC%) content ratio of each sample obtained by the above method was calculated. <Calculation of Biomass Carbon Content (%)> As shown in the above formula (3), the radiocarbon ( １４ The biomass carbon content (%) was calculated by multiplying the content ratio (pMC%) of urethane resin (B-3) by 0.93, taking into account the effects of atmospheric nuclear testing from 1950 to the present. Note that the biomass carbon content (%) of the entire urethane resin (B-3) (solid content) varies depending on the intended use, etc., so it is estimated from the weight ratio of raw material components with known biomass carbon contents (%) in the composition.

[0154] (2-1.15) Synthesis Example of Comparative Urethane Resin (A-12) A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube was charged with 213.4 parts of polypropylene glycol (EXCENOL 420, number average molecular weight 400, hydroxyl value 280 mgKOH / g, manufactured by AGC Inc.), 52.8 parts of isophorone diisocyanate, and 266 parts of ethyl acetate, and the mixture was reacted at 90°C for 6 hours under a nitrogen stream to obtain a comparative urethane resin (A-12) with a solids content of 50% and a number average molecular weight of 900.

[0155] (2-2) Preparation of Ink Composition for Flexible Packaging Laminate Example 1 2.0 parts by mass of the urethane resin (solid content) (A-1) obtained above, 30.0 parts by mass of the urethane resin (solid content) (B-1), 9 parts by mass of a polyvinyl butyral resin-containing solution (containing 15% by mass of a polyvinyl butyral resin (solid content) having a glass transition temperature (Tg) of 40 ° C. or higher), 3 parts by mass of a cellulose compound-containing solution (containing 20% ​​by mass of a cellulose compound (solid content) having a glass transition temperature (Tg) of 40 ° C. or higher), 10 parts by mass of a phthalocyanine blue pigment (FASTGEN Blue LA5380 manufactured by DIC Corporation), and 46 parts by mass of ethyl acetate were mixed and kneaded to prepare a blue printing ink composition (1) as an ink composition for flexible packaging laminate. Examples 2 to 20 Using the compositions and composition ratios shown in Table 1 below, blue printing ink compositions (2) to (20) were prepared as ink compositions for laminating flexible packaging in the same manner as in Example 1. The blue printing ink compositions (1) to (20) obtained in Examples 1 to 20 above were evaluated by measuring the flowability, adhesion, blocking resistance, extrusion laminate strength on a PET film, and dry laminate strength, as described above. The results are shown in Tables 1-1 and 1-2.

[0156] Comparative Blue Printing Ink Compositions (1) to (4) were prepared by mixing the comparative polyurethane resin (A-12) obtained above, the urethane resin (B-1) or (B-2), a polyvinyl butyral resin-containing solution (containing 15% by mass of a polyvinyl butyral resin (solid content) having a glass transition temperature (Tg) of 40°C or higher), a cellulose compound-containing solution (containing 20% ​​by mass of a cellulose compound (solid content) having 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, and grinding the mixture. The comparative blue printing ink compositions (1) to (4) obtained in Comparative Examples 1 to 4 above were evaluated for flowability, adhesion, blocking resistance, extrusion laminate strength and dry laminate strength on a PET film, as described above. The results are shown in Table 1-2.

[0157]

[0158]

[0159] The experimental results in Tables 1-1 and 1-2 above confirm that the blue printing ink compositions of the Examples can form ink layers superior in fluidity, adhesion, blocking resistance, PEEL strength, and dry laminate strength compared to the comparative blue printing ink compositions. Furthermore, comparing Example 1 with Example 5, for example, it was confirmed that when a urethane resin (B-1) with a relatively high urethane bond concentration was used, an ink layer superior in extrusion laminate strength (PEEL strength) and adhesion could be formed. It is believed that the ink layer of Example 1 improved adhesion to the substrate due to the favorable combination of urethane resin (A-1) and urethane resin (B-1), resulting in an interaction between the polar groups on the film surface and the urethane bonds of the urethane resin component in the ink layer.

[0160] This application claims the benefit of priority to Japanese Patent Application No. 2023-108806 filed on June 30, 2023 and Japanese Patent Application No. 2023-146492 filed on September 8, 2023, the contents of which are incorporated herein by reference.

Claims

1. An ink composition for flexible packaging laminates, comprising 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 (A) having a number average molecular weight of 1,000 to 3,000.

2. The urethane resin (A) has the following general formula (I): (In the above general formula (I), R ３ and R ４ 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. M in the general formula (I) represents an alkylene group having 1 to 12 carbon atoms or an arylene group having 6 to 12 carbon atoms, and the alkylene group has one or more -CH ２ The ink composition for flexible packaging laminates according to claim 2, wherein the - group may be substituted with -O- or -C(=O)-.

4. An ink composition for flexible packaging laminates according to claim 1 or 2, further comprising a urethane resin (B) having a urea bond.

5. The ink composition for flexible packaging laminates according to claim 4, wherein the urethane resin (B) is a compound having at least a polyester polyol (b2) and a polyisocyanate compound (b1) as reaction raw materials (II).

6. The liquid ink composition according to claim 5, wherein the urethane resin (B) contains a component derived from biomass.

7. The liquid ink composition according to claim 6, wherein in the urethane resin (B), the proportion of biomass-derived components in the polyester polyol (b2) contained in the reactive raw material (II) is 30 mass% or more.

8. An ink composition for flexible packaging laminates according to claim 1 or 4, further comprising a resin (C) having a glass transition temperature (Tg) of 40°C or higher.

9. An ink composition for flexible packaging laminates according to claim 2, wherein the urethane bond concentration of the urethane resin (B) is 0.6 mmol / g or more.

10. An ink composition for flexible packaging laminate according to claim 1 or 4, wherein the ratio of the urethane resin (A) to the total resin solids of the ink composition for flexible packaging laminate according to claim 1 or 4 is in the range of 1 mass% to 20 mass%.

11. An ink composition for flexible packaging laminate according to claim 1 or 4, wherein the ratio of the urethane resin (B) to the total resin solids of the ink composition for flexible packaging laminate according to claim 1 or 4 is in the range of 10 mass% to 80 mass%.

12. A printed matter obtained by printing the ink composition according to claim 1 or 4 on a substrate.

13. [Correction under Rule 26 10.06.20 24) A laminate or package comprising the printed matter according to claim 11.

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