Anchor coating compositions, printed materials, and packaging materials

Abstract

The present invention provides a printed material having electron beam-curable ink printed on a plastic film, which exhibits excellent adhesion to printed materials and is applicable to food packaging materials, and an anchor coat composition applicable thereto. [Solution] An anchor coat composition for printed materials, which is printed on a resin substrate in the order of anchor coat composition and electron beam curable ink, wherein the anchor coat composition contains a urethane resin (A) and an aqueous medium (B), and a printed material formed in the order of resin substrate, anchor coat layer and electron beam curable ink layer, wherein the anchor coat layer is a layer on which the anchor coat composition containing urethane resin (A) and aqueous medium (B) has been printed, and packaging materials.

Description

Technical Field

[0001] The present invention relates to an anchor coat composition suitable for a printed matter of an electron beam curable ink, a printed matter using the same, and a packaging material.

Background Art

[0002] Generally, ultraviolet curable inks and electron beam curable inks, which are generally called active energy ray curable inks, are both inks that are cured by irradiating active energy and are environmentally friendly inks that do not require solvents. However, since ultraviolet curable inks require a photoinitiator, for example, when applying a printed matter to a food packaging material or the like, there is a concern that the photoinitiator, which is a low molecular weight substance, may migrate into the packaged food. On the other hand, since electron beam curable inks are cured by electron beams, they do not require a photoinitiator and the concern about migration is reduced. However, since electron beam irradiation itself has not been widely spread in Japan, many considerations are still required to industrially provide food packaging materials or the like using electron beam curable inks.

[0003] When printing an electron beam curable ink on a plastic film used as a base material for a food packaging material, there is a problem that the adhesion of the electron beam curable ink to the plastic film tends to be insufficient. In contrast, for example, in Patent Document 1, a printing film obtained by coating a coating agent containing a polyester resin having a hydroxyl group and a compound having an isocyanate group and using an organic solvent as a solvent on a plastic film as an anchor coat agent, and offset printing an electron beam curable ink thereon is disclosed. Further, in Patent Document 2, a printing composition flexographically printed on a plastic film in the order of an anchor coat agent, a color ink containing process colors and special colors, and a white ink, wherein the anchor coat agent and the white ink use an aqueous polyurethane resin as a binder, and the color ink uses an aqueous acrylic resin or an ultraviolet / electron beam curable resin as a binder is disclosed.

[0004] However, since the coating agent disclosed in Patent Document 1 uses an organic solvent, the resulting food packaging material cannot be said to be completely environmentally friendly, even if an electron beam curable ink that does not require a solvent is used. Furthermore, the embodiment specifically disclosed in Patent Document 2 is a printed structure printed using an aqueous flexographic ink anchor varnish (aqueous polyurethane resin) while irradiating it with an ultraviolet curable flexographic ink using a metal halide lamp and a high-pressure mercury lamp (see Patent Document 2, Example 6), which cannot be said to be a sufficient disclosure for those skilled in the art who use electron beam curable inks. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2023-49235 [Patent Document 2] Japanese Patent Publication No. 2005-225083 [Overview of the project] [Problems that the invention aims to solve]

[0006] The object of the present invention is to provide a printed material having electron beam-curable ink printed on a plastic film, which has excellent adhesion to printed materials and can be applied to food packaging materials and the like, and an anchor coat composition applicable thereto. [Means for solving the problem]

[0007] As a result of diligent research, the present inventors have found that an anchor coat composition for printed materials, which is printed on a resin substrate in the order of anchor coat composition and active energy ray curable ink, wherein the anchor coat composition contains a urethane resin and an aqueous medium, solves the aforementioned problem.

[0008] In other words, the present invention provides an anchor coat composition for printed materials, which is printed on a resin substrate in the order of anchor coat composition and electron beam curable ink, wherein the anchor coat composition contains a urethane resin (A) and an aqueous medium (B).

[0009] The present invention also provides the anchor coat composition described above, wherein the urethane resin (A) is a urethane resin which is a reaction product of a polyol containing a polyether polyol and a polyisocyanate.

[0010] The present invention also provides the anchor coat composition described above, wherein the urethane resin (A) does not contain a polyester polyol as the polyol.

[0011] The present invention also provides the anchor coat composition described above, wherein the aqueous medium (B) is water alone, or a mixture of water and an organic solvent that is miscible with water.

[0012] The present invention also provides a printed article formed in the order of a resin substrate, an anchor coat layer, and an electron beam curable ink layer, wherein the anchor coat layer is a layer on which an anchor coat composition containing a urethane resin (A) and an aqueous medium (B) has been printed.

[0013] The present invention also provides the printed material described above, wherein the urethane resin (A) is a urethane resin which is a reaction product of a polyol containing a polyether polyol and a polyisocyanate.

[0014] The present invention also provides the printed material described above, wherein the electron beam-curable ink layer is a printed layer printed by a lithographic offset printing method or a flexographic printing method.

[0015] The present invention also provides a packaging material using the printed material described above. [Effects of the Invention]

[0016] According to the present invention, there can be provided a printed matter in which an electron beam-curable ink is printed on a plastic film, which has excellent adhesion to printed matter and is applicable to food packaging materials and the like, and an anchor coat composition applicable thereto.

Embodiments for Carrying Out the Invention

[0017] In this specification, "~" means greater than or equal to the value before the description of "~" and less than or equal to the value after the description of "~".

[0018] (Anchor coat composition) The anchor coat composition of the present invention contains a urethane resin (A) and an aqueous medium (B).

[0019] (Urethane resin) In the present invention, the urethane resin (A) is not particularly limited as long as it is a urethane resin that is well dispersed or dissolved in the aqueous medium (B). Particularly good examples include those obtained by reacting a polyol (a1) containing a polyol (a1-1) having an acid group and a polyether polyol (a1-2) other than the polyol (a1-1) with a polyisocyanate (a2).

[0020] Examples of the polyol (a1-1) having an acid group include a polyol having a carboxyl group and a polyol having a sulfonic acid group.

[0021] Examples of the polyol having a carboxyl group include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolvaleric acid, etc. Among them, 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid, which have good dispersion stability, are preferred. In addition, a polyester polyol having a carboxyl group obtained by reacting the polyol having a carboxyl group with various polycarboxylic acids can also be used. These polyols having a carboxyl group can be used alone or in combination of two or more.

[0022] Examples of polyols having sulfonic acid groups include polyester polyols obtained by reacting dicarboxylic acids such as 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, and 5-(4-sulfophenoxy)isophthalic acid, or their salts, with low molecular weight polyols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, and neopentyl glycol. These polyols having sulfonic acid groups can be used individually or in combination of two or more.

[0023] The acid group-containing polyol (a1-1) is preferably used in a range where the acid value of the urethane resin (A) is 10 to 50, and more preferably in a range of 10 to 35. In this invention, the acid value is a theoretical value calculated based on the amount of acid group-containing compound, such as the acid group-containing polyol (a1-1), used in the production of the urethane resin (A).

[0024] For good water dispersibility, it is preferable that some or all of the aforementioned acidic groups are neutralized by metal ions such as sodium, potassium, calcium, copper, and lithium to form metal salts. The neutralization rate is preferably in the range of 30 to 130%, and more preferably in the range of 50 to 100%.

[0025] The metal ions such as sodium, potassium, calcium, copper, and lithium that can be used to neutralize the acid group can be obtained, for example, from metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide, metal chlorides such as sodium chloride and potassium chloride, and metal sulfides such as copper sulfate.

[0026] Examples of the polyether polyols (a1-2) include those obtained by addition polymerization of alkylene oxide using one or more compounds having two or more active hydrogen atoms as initiators.

[0027] Examples of the initiators include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, bisphenol A, glycerin, trimethylolethane, trimethylolpropane, and the like.

[0028] Examples of the alkylene oxides include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, and tetrahydrofuran.

[0029] It is preferable to use a polyether polyol with a number average molecular weight of 500 to 3000.

[0030] Furthermore, in addition to the polyols described above, polyols (a1-3) having an alicyclic structure can be used as the polyol (a1).

[0031] Examples of polyols having an alicyclic structure (a1-3) include cyclobutanediol, cyclopentanediol, 1,4-cyclohexanediol, cycloheptanediol, cyclooctanediol, cyclohexanedimethanol, hydroxypropylcyclohexanol, dicyclohexanediol, butylcyclohexanediol, 1,1'-bicyclohexylidenediol, cyclohexanetriol, hydrogenated bisphenol A, and 1,3-adamantanediol, all of which are low molecular weight polyols containing an alicyclic structure, generally around 100 to 500. These polyols having an alicyclic structure can be used individually or in combination of two or more.

[0032] Furthermore, it is preferable that the polyol (a1-3) is used in an amount of 0 to 20% by mass of the total amount of polyol (a1).

[0033] Examples of polyisocyanates (a2) that can react with the polyol (a1) include aromatic polyisocyanates such as 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, phenylene diisocyanate, triene diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, and tetramethylxylylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate and lysine diisocyanate; and polyisocyanates having an alicyclic structure such as cyclohexane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate. These polyisocyanates (a2) can be used alone or in combination of two or more.

[0034] A method for producing a urethane resin (A) obtained by reacting the polyol (a1) and the polyisocyanate (a2) is, for example, a method in which the polyol (a1) and the polyisocyanate (a2) are mixed in the absence of a solvent or in the presence of an organic solvent, and the reaction is carried out at a reaction temperature in the range of 50°C to 150°C.

[0035] The reaction between the polyol (a1) and the polyisocyanate (a2) is preferably carried out in a range of 0.8 to 2.5 for the equivalent ratio of the isocyanate groups of the polyisocyanate (a2) to the hydroxyl groups of the polyol (a1), and more preferably in a range of 0.9 to 1.5.

[0036] Furthermore, it is preferable to use a urethane resin (A) that has an alicyclic structure because it can suppress blocking.

[0037] Examples of the alicyclic structures include cyclobutyl ring, cyclopentyl ring, cyclohexyl ring, cycloheptyl ring, cyclooctyl ring, propylcyclohexyl ring, tricyclo[5.2.1.0.2.6]decyl skeleton, bicyclo[4.3.0]-nonyl skeleton, tricyclo[5.3.1.1]dodecyl skeleton, propyltricyclo[5.3.1.1]dodecyl skeleton, norbornene skeleton, isobornyl skeleton, dicyclopentanyl skeleton, and adamantyl skeleton. Among these, the cyclohexyl ring structure is preferred.

[0038] The presence of the alicyclic structure in the urethane resin (A) at a concentration of 1000 mmol / kg to 5000 mmol / kg is preferable because it can suppress blocking of the printed material. In particular, a range of 1000 mmol / kg to 4000 mmol / kg is preferred. Furthermore, a range of 1000 mmol / kg to 3000 mmol / kg is even more preferable, as it allows for the production of an ink with excellent resolubility and blocking properties. Furthermore, the calculation method refers to the total moles of the alicyclic structure added per 1 kg of non-volatile components of the urethane resin.

[0039] The alicyclic structure preferably includes an alicyclic structure derived from a polyol having an alicyclic structure that can be used as a polyol (a1) when manufacturing the urethane resin (A). However, it is not necessary for all of it to be derived from a polyol having an alicyclic structure; some of it may be derived from an alicyclic structure-containing polyisocyanate such as isophorone diisocyanate.

[0040] In this invention, the ratio of the alicyclic structure contained in the urethane resin (A) to the total amount of the urethane resin (A) is a value calculated based on the total mass of all raw materials such as polyol (a1) and polyisocyanate (a2) used in the production of the urethane resin (A) and the amount of substance of the alicyclic structure in the alicyclic structure-containing compound used in the production of the urethane resin (A).

[0041] Furthermore, a chain extender can be used as needed when manufacturing the urethane resin (A).

[0042] Examples of the chain elongators include polyamines, hydrazine compounds, and other compounds having active hydrogen atoms. These chain elongators can be used alone or in combination of two or more.

[0043] Examples of the polyamines include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4'-dicyclohexylmethanediamine, 3,3'-dimethyl-4,4'-dicyclohexylmethanediamine, 1,4-cyclohexanediamine, and other diamines; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, N-ethylaminoethylamine, N-methylaminopropylamine, diethylenetriamine, dipropylenetriamine, triethylenetetramine, and the like. Among these, ethylenediamine is preferred.

[0044] Examples of the hydrazine compounds include hydrazine, N,N'-dimethylhydrazine, 1,6-hexamethylenebishydrazine, succinate dihydrazide, adipic acid dihydrazide, glutarate dihydrazide, sebacate dihydrazide, isophthalate dihydrazide, β-semicarbazidepropionate hydrazide, 3-semicarbazide-propylcarbadate ester, semicarbazide-3-semicarbazidemethyl-3,5,5-trimethylcyclohexane, and the like.

[0045] Examples of the aforementioned compounds having active hydrogen include glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, saccharose, methylene glycol, glycerin, and sorbitol; phenols such as bisphenol A, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfone, hydrogenated bisphenol A, and hydroquinone; and water.

[0046] When a polyamine is used as the chain extension agent, for example, the equivalent ratio [amino group / isocyanate group] of the amino group to the isocyanate group of the polyamine is preferably 1.2 or less, and more preferably in the range of 0.3 to 1.

[0047] Examples of organic solvents that can be used when manufacturing the urethane resin (A) include ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran and dioxane; acetic acid ester solvents such as ethyl acetate and butyl acetate; nitrile solvents such as acetonitrile; and amide solvents such as dimethylformamide and N-methylpyrrolidone. These organic solvents can be used individually or in combination of two or more.

[0048] Furthermore, in order to ensure safety and reduce the burden on the environment, some or all of the organic solvent may be removed during or after the manufacturing of the urethane resin (A), for example, by distillation under reduced pressure.

[0049] The urethane resin (A) obtained by the above method can exhibit durability in printed materials, so it is preferable to use one having a weight-average molecular weight in the range of 5,000 to 500,000, more preferably one having a weight-average molecular weight in the range of 5,000 to 200,000, and even more preferably one having a weight-average molecular weight in the range of 20,000 to 100,000. Furthermore, the weight-average molecular weight (in polystyrene equivalent) was measured by GPC (gel permeation chromatography) in this invention using the HLC8220 system manufactured by Tosoh Corporation under the following conditions. Separation column: Four TSKgelGMHHR-N columns manufactured by Tosoh Corporation were used. Column temperature: 40°C. Mobile phase: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd. Flow rate: 1.0 ml / min. Sample concentration: 0.4 mass%. Sample injection volume: 100 microliters. Detector: Differential refractometer.

[0050] When the weight-average molecular weight falls below 5,000, not only is the durability of the printed material reduced, but problems such as blocking due to poor drying tend to occur. When the molecular weight exceeds 500,000, problems such as poor ink transfer and reduced resolubility are likely to occur.

[0051] Furthermore, the aqueous form of the urethane resin (A) produced by the above method can be carried out, for example, by the following method.

[0052] [Method 1] A method for dispersing urethane resin (A) in water by reacting a polyol (a1) with a polyisocyanate (a2), neutralizing some or all of the acid groups of the aqueous urethane resin, adding an aqueous medium (B) to disperse it in water, and then extending the chain using the chain extender.

[0053] [Method 2] A method in which an aqueous urethane resin obtained by reacting a polyol (a1) and a polyisocyanate (a2), and a chain extender similar to the above are charged into a reaction vessel all at once or in portions, and a chain extension reaction is carried out to produce a urethane resin (A), and then some or all of the acid groups in the obtained urethane resin (A) are neutralized, and then an aqueous medium (B) is added and dispersed in water.

[0054] In the above methods [1] and [2], emulsifiers may be used as needed. Also, when dissolving or dispersing in water, machinery such as a homogenizer may be used as needed.

[0055] Examples of the aqueous medium (B) include water, a water-miscible organic solvent, and mixtures thereof. Examples of water-miscible organic solvents include alcohol solvents such as methanol, ethanol, n-propanol, and isopropanol; ketone solvents such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol, and propylene glycol; alkyl ethers of polyalkylene glycols; and lactam solvents such as N-methyl-2-pyrrolidone. In the present invention, water alone may be used, a mixture of water and a water-miscible organic solvent may be used, or a water-miscible organic solvent may be used alone.

[0056] Furthermore, as the aqueous medium (B), from the viewpoint of safety and environmental impact, water alone or a mixture of water and an organic solvent that is miscible with water is preferred, and water alone is particularly preferred.

[0057] Examples of the emulsifiers include nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styrylphenyl ether, polyoxyethylene sorbitol tetraoleate, and polyoxyethylene-polyoxypropylene copolymer; anionic emulsifiers such as fatty acid salts such as sodium oleate, alkyl sulfate esters, alkylbenzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, polyoxyethylene alkyl sulfates, sodium alkanesulfonates, and sodium alkyldiphenyl ethersulfonates; and cationic emulsifiers such as alkylamine salts, alkyltrimethylammonium salts, and alkyldimethylbenzylammonium salts. Among these, anionic or nonionic emulsifiers are preferred from the viewpoint of maintaining the excellent storage stability of the aqueous flexographic ink of the present invention.

[0058] The anchor coat composition of the present invention, in which the urethane resin (A) obtained by the above method is dispersed in an aqueous medium (B), preferably contains the urethane resin (A) in an amount of 50 to 100% by mass relative to the total amount of nonvolatile components of the anchor coat composition, and in an amount of 10 to 50% by mass relative to the total amount of the anchor coat composition. By including the urethane resin (A) in an amount of 50 to 100% by mass relative to the total amount of nonvolatile components of the anchor coat composition, adhesion to the substrate is improved, while including it in an amount of 10 to 50% by mass relative to the total amount of the anchor coat composition is preferable in suppressing blocking and the like.

[0059] Other resins that can be incorporated into the binder for aqueous liquid ink of the present invention include aqueous or water-dispersible resins, particularly those with an acid value of 5 to 150 mgKOH / g. Examples include acrylic resins, styrene-acrylic resins, maleic acid resins, styrene-maleic acid resins, α-olefin maleic acid resins, ester resins, sulfonic acid resins, and phosphoric acid resins. Among these, styrene-maleic acid copolymers are preferred. For example, the amount added to a styrene-maleic acid copolymer is preferably 1 to 10% by mass of the total liquid ink volume. In addition, a portion of the resin may function as a pigment dispersant.

[0060] (Printed material) The present invention relates to a printed material formed in the order of a resin substrate, an anchor coat layer, and an active energy ray curable ink layer, characterized in that the anchor coat layer is a layer on which the anchor coat composition has been printed.

[0061] (Resin base material) The resin substrate used in the present invention is not particularly limited, and resin substrates commonly used in packaging materials, especially food packaging materials, can be used. Specifically, examples include polyethylene terephthalate (PET) film, polystyrene film, polyamide film, nylon film, polyacrylonitrile film, polyolefin films such as polyethylene film (OPE: biaxially oriented polyethylene film, LLDPE: low-density polyethylene film, HDPE: high-density polyethylene film) and polypropylene film (CPP: unoriented polypropylene film, OPP: biaxially oriented polypropylene film), polyvinyl alcohol film, ethylene-vinyl alcohol copolymer film, cellophane, and the like.

[0062] Furthermore, films can be used that have inorganic vapor-deposited layers such as film silica or metal oxides like alumina. Specific examples include OPE films, OPP films, PET films, and nylon films having a silica vapor-deposited layer, and OPE films, OPP films, PET films, and nylon films having an alumina vapor-deposited layer.

[0063] When considering monomaterial packaging, a film made of a thermoplastic resin mainly composed of olefin resin can be used as the base material. Specifically, olefin resins include polyethylene such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; polypropylene; ethylene-propylene copolymer; α-olefin polymer; ethylene-vinyl acetate copolymer; ethylene-vinyl alcohol copolymer; ethylene-acrylic acid copolymer; ethylene-methyl methacrylate copolymer; ethylene-ethyl acrylate copolymer; cyclic olefin resin; ionomer resin; and polymethylpentene; as well as modified olefin resins obtained by modifying olefin resin with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, or other unsaturated carboxylic acids.

[0064] Furthermore, it is preferable to use a film made from a material containing biomass-derived components as the film substrate. Biomass films are sold by various companies, and for example, sheets listed in the biomass certified product list provided by the Japan Organic Resources Association can be used.

[0065] A well-known example of a film made from biomass-derived ethylene glycol is derived from ethanol produced from biomass (biomass ethanol). For example, biomass-derived ethylene glycol can be obtained by conventionally known methods, such as a method that produces ethylene glycol via ethylene oxide from biomass ethanol. Alternatively, commercially available biomass ethylene glycol may be used; for example, the biomass ethylene glycol commercially available from India Glycol can be suitably used.

[0066] Alternatively, products using biomass raw materials, distinguished by their biomass plasticity as defined by ISO 16620 or ASTM D6866, are also available. Radioactive carbon-14C exists in the atmosphere at a rate of 1 in 10¹² atoms, and this rate does not change even in atmospheric carbon dioxide. Therefore, this rate does not change in plants that fix carbon dioxide through photosynthesis. For this reason, the carbon in plant-derived resins contains radioactive carbon-14C. In contrast, the carbon in fossil fuel-derived resins contains almost no radioactive carbon-14C. Therefore, by measuring the concentration of radioactive carbon-14C in the resin using an accelerator mass spectrometer, the proportion of plant-derived resin in the resin, i.e., the biomass plasticity, can be determined. Examples of plant-derived low-density polyethylene (PPE) biomass plastics with a biomass plastic content of 80% or more, preferably 90% or more, as defined by ISO 16620 or ASTM D6866, include Braskem's product names "SBC818," "SPB608," "SBF0323HC," "STN7006," "SEB853," and "SPB681," and films made from these materials can be suitably used.

[0067] For example, as an alternative to conventional polyolefin films using petroleum-based raw materials, biomass polyolefin films such as biomass polyethylene films and biomass polyethylene-polypropylene films, which contain polyethylene resin made from biomass-derived ethylene glycol, are also known. The polyethylene resin is not particularly limited except for the use of biomass-derived ethylene glycol as part of the raw materials. Examples include ethylene homopolymers and copolymers of ethylene and α-olefins with ethylene as the main component (ethylene-α-olefin copolymers containing 90% by mass or more of ethylene units). These can be used individually or in combination of two or more types. The α-olefin constituting the copolymer of ethylene and α-olefin is not particularly limited, and examples include α-olefins having 4 to 8 carbon atoms, such as 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Known polyethylene resins such as low-density polyethylene resin, medium-density polyethylene resin, and linear low-density polyethylene resin can be used. Among these, linear low-density polyethylene resin (LLDPE) (a copolymer of ethylene and 1-hexene, or a copolymer of ethylene and 1-octene) is preferred, and linear low-density polyethylene resin with a density of 0.910 to 0.925 g / cm3 is more preferred, from the viewpoint of making it even less likely for damage such as punctures or tears to occur when the films rub against each other.

[0068] The biomass film may be a laminate formed by stacking multiple biomass films, or it may be a laminate formed by combining a conventional petroleum-based film with a biomass film.

[0069] The substrate may be subjected to some kind of surface treatment, such as physical treatments like corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, or flame treatment, or chemical treatments such as oxidation treatment using chemicals, or other treatments.

[0070] The aforementioned substrate can be manufactured using conventionally known film-forming methods such as extrusion, casting, T-die, cutting, and inflation methods. It may be an unstretched film, or, from the viewpoint of strength, dimensional stability, and heat resistance of the film (1), it may be stretched in one or two axes using a tenter method, tubular method, or the like.

[0071] The aforementioned substrate may contain additives as needed. Specifically, plastic compounding agents and additives such as elastomers, lubricants, crosslinking agents, antioxidants, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, and pigments may be added for the purpose of improving or modifying properties such as processability, heat resistance, weather resistance, mechanical properties, dimensional stability, oxidation resistance, slipperiness, mold release properties, flame retardancy, mold resistance, electrical properties, and strength. The amount of additives added should be adjusted within a range that does not affect other properties or recyclability.

[0072] The film thickness of the substrate is not particularly limited and can be appropriately selected within the range of 0.1 to 300 μm from the viewpoint of moldability and transparency. Preferably, it is in the range of 0.3 to 100 μm. If it is less than 0.1 μm, the strength will be insufficient, and if it exceeds 300 μm, the rigidity will be too high, which may make processing difficult.

[0073] (Anchor coat layer) An anchor coat layer is obtained by printing the anchor coat composition of the present invention onto the resin substrate. The printing method for obtaining the anchor coat layer is not particularly limited and can be carried out using known printing methods. For example, in addition to offset printing machines and flexographic printing machines, roll coaters, gravure coaters, flexographic coaters, air doctor coaters, blade coaters, air knife coaters, squeeze coaters, impregnation coaters, transfer roll coaters, kiss coaters, curtain coaters, cast coaters, spray coaters, die coaters, gravure printing machines, screen printing machines, etc., can also be used as appropriate. Among these, a flexographic printing method is preferred.

[0074] (Flexographic printing method) Flexographic printing is not particularly limited; it can be done using a common rubber plate as the printing plate (relief plate), with a fine-mesh engraved roll called an anilox roll used to supply ink to the plate. The anilox roll receives ink from the chamber-type doctor and applies it to the printing plate, and has the advantage of uniformly transferring ink to the plate via the anilox roll.

[0075] Specifically, ink is applied to the surface of an anilox roll having partitions and numerous openings surrounded by the partitions. A doctor is pressed against the surface of the anilox roll to scrape off the ink present on the top surface of the partitions and fill the recessed openings with ink. Next, a flexographic plate is pressed against the anilox roll to transfer the ink present in the recessed areas of the anilox roll to the raised areas (pattern areas) of the printing plate. Then, the plate is brought into contact with the substrate to transfer the ink present in the pattern areas of the plate to the substrate, thereby obtaining a printed product.

[0076] Furthermore, a rotary printing method may be combined. For example, in a method for manufacturing a rotary printed plastic film, rotary printing is performed on the surface of a rolled plastic film using a water-based liquid printing ink. After printing, processes such as lamination, slitting (cutting off unnecessary parts of the width), and bag making (cutting and heat-sealing to make bags) can be carried out. By rotary printing liquid printing ink onto a rolled plastic film, high-speed printing is possible, resulting in excellent productivity.

[0077] Since the anchor coating composition of the present invention contains an aqueous medium, the printed layer is usually obtained by printing it onto a resin substrate and then drying and fixing it by drying in an oven. The drying temperature is generally around 40 to 60°C.

[0078] The thickness of the anchor coat layer is not particularly limited and can be appropriately determined based on various factors such as ink drying properties during printing and running costs. However, generally, the thickness after drying is preferably 0.01 to 3 μm, and more preferably 0.05 to 2 μm.

[0079] (Printing layer) In this invention, the printed layer is a layer printed with an electron beam-curable ink. The printing method is not particularly limited in this invention. The films used as the substrate often use printing inks produced by gravure printing, flexographic printing, lithographic offset printing, inkjet recording printing, etc. The printed layer is obtained by curing the ink printed by these printing methods with an electron beam (also called EB).

[0080] Specifically, examples include electron beam-curable inks for offset lithographic printing, electron beam-curable inks for flexographic printing, electron beam-curable inks for gravure printing, and electron beam-curable inks for inkjet recording printing.

[0081] (Offset printing method) Printing using the lithographic offset printing method can be done in any way without particular limitations, using general color process inks or spot color inks, either as single colors or in multi-color overprinting. Offset printing presses are manufactured and sold by numerous printing press manufacturers, including Heidelberg, Komori Corporation, Ryobi MHI Graphic Technology, Manroland, and KBA. The present invention can be suitably used with both sheet-fed offset printing presses using sheet-type printing paper and web offset printing presses using reel-type printing paper. More specifically, examples of offset printing presses include the Speedmaster series from Heidelberg, the Lithrone series from Komori Corporation, and the RMGT series from Ryobi MHI Graphic Technology.

[0082] The thickness of the printed layer on the substrate after printing using the lithographic offset printing method is approximately 0.5 to 3 μm per color in the wet state before electron beam irradiation, and is preferably in the range of 1.0 to 1.5 μm.

[0083] (Flexographic printing method) The flexographic printing method can be used to print using the same method as the flexographic printing method described for the anchor coat layer.

[0084] The above printing method can be appropriately selected depending on the desired film thickness of the printed layer. For example, for color printing to display images or text, a thin-film offset printing method is preferred, while for solid color printing such as white solid layers or overprint layers, a certain film thickness is preferred, so a flexographic printing method is preferred. In addition to offset and flexographic printing presses, roll coaters, gravure coaters, flexographic coaters, air doctor coaters, blade coaters, air knife coaters, squeeze coaters, impregnation coaters, transfer roll coaters, kiss coaters, curtain coaters, cast coaters, spray coaters, die coaters, gravure printing presses, screen printing presses, etc. can also be used as appropriate for solid color printing.

[0085] (Electron beam curing method) After printing using the various printing methods described above, the printed material is cured by electron beam curing. The electron beam used is usually an electron beam (also called Electron Bearm EB) that has been artificially accelerated using an accelerator. The energy intensity of the electron beam used is determined appropriately depending on the printing method and the thickness of the printed layer, but it is generally 30,000 to 300,000 eV, and the irradiation dose is often 5 to 100 kGy·m / min. (kilogray).

[0086] (Electron beam curable ink) The electron beam curable ink used in this invention can be selected as appropriate from those commonly used as electron beam curable inks, depending on the printing method. Generally, it contains a compound having an ethylenic double bond, and optionally a resin, additives, etc.

[0087] (Compounds containing ethylenic double bonds) Examples of compounds having an ethylenic double bond include (meth)acrylates and additives. In this invention, "(meth)acrylate" refers collectively to acrylates and methacrylates. Examples of monofunctional (meth)acrylates include ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, isoamyl (meth)acrylate, isodecyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxydiethylene glycol ( Examples include meth)acrylate, nonylphenoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, diethylaminoethyl (meth)acrylate, nonylphenoxyethyl tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate.

[0088] Examples of (meth)acrylates with two or more functionalities include 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, tricyclodecanedimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, Diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and other dihydric alcohol di(meth)acrylates; polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, tris(2-hydroxyethyl) isocyanurate di(meth)acrylate; neopentyl glycol with 4 moles or more of ethylene oxide or propylene oxide per mole. Di(meth)acrylates of diols obtained by adding an aldehyde, di(meth)acrylates of diols obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, poly(meth)acrylate of dipentaerythritol, and other poly(meth)acrylates of trivalent or higher polyhydric alcohols. Examples include tri(meth)acrylates of triols obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of glycerin, di(meth)acrylates of triols obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane, and poly(meth)acrylates of polyoxyalkylene polyols such as di(meth)acrylates of diols obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A.

[0089] Examples of polymerizable oligomers include amine-modified polyether acrylates, as well as polyester (meth)acrylates, polyether (meth)acrylates, polyolefin (meth)acrylates, polystyrene (meth)acrylates, epoxy (meth)acrylates, and urethane (meth)acrylates. As a compound having an ethylenic double bond, it is preferable to use the above polymerizable oligomer and acrylate monomer in combination.

[0090] The total amount of compounds having ethylenic double bonds is preferably in the range of 30 to 100% by mass of the total ink amount, more preferably 40 to 1000% by mass, and even more preferably in the range of 50 to 100% by mass. Furthermore, from the viewpoint of achieving excellent curability and excellent fluidity through the combined use of various compounds, the amounts of both added are preferably within this range.

[0091] Electron beam printing inks may further contain stabilizers, polymerization inhibitors, silicone-based additives, waxes, pigments, dyes, etc., as needed.

[0092] Examples of the stabilizers include phenolic compounds such as hindered phenolic antioxidants, hindered amine antioxidants, organic sulfur antioxidants, phosphate ester antioxidants, copper carbamate complexes such as dialkyldithiocarbamate copper complexes, and nitroso compounds such as nitrosamine compounds. These stabilizers can be used individually or in combination of two or more. The amount of these stabilizers used is preferably in the range of 0.01% to 0.3% by mass of the total ink volume, as this provides a good effect in improving storage stability.

[0093] Examples of the aforementioned silicone-based additives include polyorganosiloxanes having alkyl or phenyl groups, such as dimethylpolysiloxane, methylphenylpolysiloxane, cyclic dimethylpolysiloxane, methylhydrogenpolysiloxane, polyether-modified dimethylpolysiloxane copolymer, polyester-modified dimethylpolysiloxane copolymer, fluorine-modified dimethylpolysiloxane copolymer, and amino-modified dimethylpolysiloxane copolymer; polydimethylsiloxane having polyether-modified acrylic groups; and polydimethylsiloxane having polyester-modified acrylic groups. These silicone-based additives can be used individually or in combination of two or more. From the viewpoint of achieving excellent smoothness and excellent abrasion resistance, the amount of these silicone-based additives used is preferably in the range of 0.05% to 1% by mass of the total ink volume.

[0094] Examples of the aforementioned waxes include paraffin wax, carnauba wax, beeswax, microcrystalline wax, polyethylene wax, oxidized polyethylene wax, polytetrafluoroethylene wax, amide wax, and fatty acids with approximately 8 to 18 atomic carbon atoms, such as coconut oil fatty acids and soybean oil fatty acids. From the viewpoint of achieving both excellent curability and excellent abrasion resistance, the amount of these waxes used is preferably in the range of 0.5% to 4% by mass of the total ink amount.

[0095] When used as a coloring agent in colored inks, etc., inorganic or organic pigments commonly used as colorants can be used. When used as a transparent coating or transparent varnish not for coloring purposes, pigments as colorants are not necessary, but extender pigments may be used as needed.

[0096] Examples of the inorganic pigments include carbon black, titanium dioxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, magnesium carbonate, talc, chromium oxide, silica, red iron oxide, aluminum, and mica. Additionally, a luminous pigment (MetaShine; Nippon Sheet Glass Co., Ltd.) coated with metal or metal oxide on a base material of glass flakes or bulk flakes can be used. Titanium dioxide is preferred for white inks, carbon black for black inks, aluminum for gold and silver inks, and mica for pearl inks, both from the standpoint of cost and coloring strength. Aluminum is available in powder or paste form, but it is preferred in paste form for ease of handling and safety. Whether to use leafing or non-leafing aluminum is appropriately selected from the viewpoint of brightness and density.

[0097] Examples of the aforementioned organic pigments include soluble azo pigments, insoluble azo pigments, azo pigments, phthalocyanine pigments, halogenated phthalocyanine pigments, anthraquinone pigments, anthancerone pigments, dianthaquinonyl pigments, anthrapyrimidine pigments, perylene pigments, perinone pigments, quinacridone pigments, thioindigo pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, azomethine azo pigments, flavanthrone pigments, diketopyrrolopyrrole pigments, isoindoline pigments, indanthrone pigments, and carbon black pigments. Other examples include carmine 6B, lake red C, permanent red 2B, disazo yellow, pyrazolone orange, carmine FB, chromophthal yellow, chromophthal red, phthalocyanine blue, phthalocyanine green, dioxazine violet, quinacridone magenta, quinacridone red, indanthrone blue, pyrimidine yellow, thioindigobordeaux, thioindigomagenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, and daylight fluorescent pigments. Both unacidified and acidified pigments can be used. These pigments can be used individually or in combination of two or more.

[0098] Furthermore, examples of dyes include azo dyes such as monoazo and disazo, metal complex dyes, naphthol dyes, anthraquinone dyes, indigo dyes, carbonium dyes, quinoimine dyes, cyanine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, naphthalimide dyes, perinone dyes, phthalocyanine dyes, and triallylmethane-based dyes. These dyes can be used individually or in combination of two or more.

[0099] (resin) Various publicly known and publicly available binder resins can be used as the resin. The binder resins described herein refer to all resins that have appropriate pigment affinity and dispersibility and possess the rheological properties required for printing inks. For example, non-reactive resins include aldehyde resins, ketone resins, phenolic resins, diallyl phthalate resins, epoxy resins, polyurethane resins, polyester resins, petroleum resins, rosin ester resins, poly(meth)acrylic acid esters, cellulose derivatives, vinyl chloride-vinyl acetate copolymers, polyamide resins, polyvinyl acetal resins, butadiene-acrylonitrile copolymers, etc. Epoxy acrylate compounds, urethane acrylate compounds, polyester acrylate compounds, etc., having at least one polymerizable group in their molecules can also be used. These binder resins may be used individually or in combination of one or more types.

[0100] The use of the aforementioned resin may involve the use of a mixed solution with a compound having an ethylenically double bond as a varnish, for the purpose of adjusting appropriate dispersibility and viscosity. From the viewpoint of suppressing misting and paper peeling, these varnishes are preferably in the range of 10 to 60% by mass of the total amount of the ink of the present invention, and more preferably 15 to 50% by mass.

[0101] Furthermore, electron beam-curable inks can be cured using electron beams without the use of a photopolymerization initiator, but a photopolymerization initiator can be included if desired. The photopolymerization initiator is not particularly limited and includes known alkylphenone-based photopolymerization initiators such as 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone (184), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (1173), 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one (2959), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methyl-propan-1-one (127), and 2-hydroxy-1-[4-[4-(2-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one,

[0102] Phenyl glyoxylic acid methyl ester, oxyphenylacetic acid, a mixture of 2-[2-oxo-2-phenylacetoxyethoxy]ethyl ester and oxyphenylacetic acid, 2-(2-hydroxyethoxy)ethyl ester, 1,2-octanedione, 1-[4-(phenylthio)-,2-(O-benzoyl oxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,1-(O-acetyl oxime), 2-methyl-1-(4-methylthiophenyl)-2-morpholi Compounds such as nopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-benzyl-2-dimethylamino-1-(4-piperidinophenyl)-butan-1-one, 1-([1,1'-biphenyl]-4-yl)-2-methyl-2-morpholinopropan-1-one, 1-(4-methoxyphenyl)-2-methyl-2-(4-morpholinyl-1-propanone),

[0103] Acyl phosphine oxide compounds such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and ethyl-(2,4,6-trimethylbenzoyl)phenylphosphinate,

[0104] In addition, thioxanthone compounds such as 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, 2-isopropylthioxanthone, 4-diisopropylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-dichlorothioxanthone, 2-chlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2-hydroxy-3-(3,4-dimethyl-9-oxo-9Hthioxanthone-2-yloxy-N,N,N-trimethyl-1-propanamine hydrochloride,

[0105] In addition, 4,4'-dialkylaminobenzophenones such as 4,4'-bis-(dimethylamino)benzophenone and 4,4'-bis-(diethylamino)benzophenone, and benzophenone compounds such as 4-benzoyl-4'-methyldiphenyl sulfide,

[0106] Examples include benzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, 2,3,4-trimethylbenzophenone, 4-phenylbenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 4-(1,3-acryloyl-1,4,7,10,13-pentaoxotridecyl)benzophenone, methyl-o-benzoylbenzoate, [4-(methylphenylthio)phenyl]phenylmethanone, diethoxyacetophenone, dibutoxyacetophenone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and benzoin n-butyl ether.

[0107] In the present invention, the general-purpose photopolymerization initiator may be used alone or in combination of several types. In this case, it is preferable to use it in an amount of 0.1 to 20% by mass, and more preferably in an amount of 0.1 to 10% by mass, relative to the total amount of non-volatile components of the ink.

[0108] Furthermore, sensitizers and photoinitiators may be used as desired. While not particularly limited, examples of photosensitizers include thioxanthones, benzophenones such as 4,4'-bis(diethylamino)benzophenone, anthraquinones, and coumarins. When using sensitizers and photoinitiators in combination, the amount is preferably 0.05 to 10% by mass, and more preferably 0.1 to 7.0% by mass, relative to the total amount of non-volatile components of the ink.

[0109] (Printed materials, laminates) The printed material of the present invention is not particularly limited as long as it is printed in the order of the resin substrate, the anchor coat layer, and the electron beam curable ink layer. However, since the anchor coat layer is a layer intended to improve the adhesion between the resin substrate and the electron beam curable ink layer, it is preferable that each layer is in close contact with the others.

[0110] Herein are some examples of specific embodiments of the printed material of the present invention. Of course, the printed material of the present invention is not limited to these embodiments. Furthermore, a laminate can be formed by laminating the printed material of the present invention with a second resin substrate using an adhesive.

[0111] Resin substrate / Anchor coat layer / Electron beam curable color ink printed using a lithographic offset printing method Resin substrate / Anchor coat layer / Electron beam curable color ink printed using flexographic printing method Resin substrate / Anchor coat layer / Electron beam curable color ink printed using a lithographic offset printing method / Electron beam curable colorless ink solid print using a flexographic printing method

[0112] Resin substrate / Anchor coat layer / Electron beam curable color ink printed using a lithographic offset printing method / Adhesive layer / Second resin substrate Resin substrate / Anchor coat layer / Electron beam curable color ink printed using flexographic printing method / Adhesive layer / Second resin substrate Resin substrate / Anchor coat layer / Electron beam curable color ink printed using lithographic offset printing / Electron beam curable white ink solid print using flexographic printing / Adhesive layer / Second resin substrate

[0113] (glue) The adhesive used in the aforementioned printed material or laminate can be any adhesive that can be used in a general-purpose lamination method. Examples of lamination methods include dry lamination, wet lamination, non-solvent lamination, and extrusion lamination. After the adhesive hardens or dries, it forms an adhesive layer.

[0114] As the adhesive used in the dry lamination, for example, one-component or two-component curing or non-curing type adhesives such as vinyl-based, (meth)acrylic-based, polyamide-based, polyester-based, polyether-based, polyurethane-based, epoxy-based, rubber-based, and others can be used, and are available in solvent-based, water-based, or emulsion-based types. As a two-component curing type adhesive, a two-component curing type adhesive of polyol and isocyanate compound can be used. As the coating method for the laminating adhesive, for example, it can be applied by the direct gravure roll coating method, gravure offset roll coating method, kiss coating method, reverse roll coating method, fontein method, transfer roll coating method, and other methods. For example, the DIC Dry series manufactured by DIC Corporation can be preferably used.

[0115] Furthermore, various adhesives can be used, and pressure-sensitive adhesives are preferred. Examples of 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, or hexane; or rubber-based adhesives obtained by compounding these with tackifiers such as rosin aviethylene acid ester, terpene-phenol copolymer, or terpene-indene copolymer; or acrylic-based adhesives obtained by dissolving acrylic copolymers with a glass transition temperature of -20°C or lower, such as 2-ethylhexyl acrylate-n-butyl acrylate copolymer or 2-ethylhexyl acrylate-ethyl acrylate-methyl methacrylate copolymer, in an organic solvent.

[0116] In the aforementioned adhesive, a functional adhesive may be used. For example, as a gas barrier adhesive, the PASLIM series of oxygen barrier adhesives manufactured by DIC Corporation, which is a two-component reactive adhesive consisting of a polyester polyol and an isocyanate compound, can be used. After the gas barrier adhesive hardens or dries, it becomes a gas barrier adhesive layer. Using a gas barrier adhesive is preferable because it can further enhance the gas barrier properties of the laminate of the present invention.

[0117] When the adhesive is solvent-based, the adhesive is applied to one substrate using a roll such as a gravure roll, the organic solvent is evaporated by heating in an oven or the like, and then the other substrate is bonded to obtain the laminate of the present invention. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably room temperature to 80°C, and the aging time is preferably 12 to 240 hours.

[0118] If the adhesive is solvent-free, the fragrance-retaining adhesive, which has been preheated to approximately 40°C to 100°C, is applied to one substrate using a roll such as a gravure roll, and then the other substrate is immediately bonded to obtain the laminate of the present invention. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably room temperature to 70°C, and the aging time is preferably 6 to 240 hours.

[0119] The amount of adhesive applied should be adjusted as needed. For solvent-based adhesives, for example, the amount of non-volatile components should be 1 g / m². 2 More than 10g / m 2 Preferably 1 g / m 2 More than 5g / m 2 Adjust the following: For solvent-free types, the amount of adhesive applied is, for example, 1 g / m². 2 More than 10g / m 2 Preferably 1 g / m 2 More than 5g / m 2 The following applies:

[0120] The second resin substrate used in the printed material or laminate can be bonded to the ink layer of the electron beam-curable color ink printed by, for example, the resin substrate / anchor coat layer / lithographic offset printing method using an adhesive, or the second substrate may be formed on the printed material or laminate by an extrusion method. The second substrate may be the same type as the first substrate or a different substrate. When applying the printed material or laminate of the present invention to packaging material, assuming that the second substrate is used as a sealant layer, the second substrate can be selected as a polyolefin resin with heat-sealability. Examples include polyethylene resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), very low-density polyethylene (VLDPE), polypropylene (CPP), ethylene-propylene copolymer, and polymethylpentene; and ethylene copolymers such as ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), ethylene-acrylic acid copolymer (EAA), and ethylene-methacrylic acid copolymer (EMAA); and further, ionomers of ethylene-acrylic acid copolymer and ionomers of ethylene-methacrylic acid copolymer, which may be used individually or in combination of two or more. When the second layer is a heat-seal layer, its film thickness can be adjusted as appropriate depending on the purpose, but from the viewpoint of aroma retention and heat sealability, it is typically 1 μm to 10 μm, and more preferably 3 μm to 10 μm.

[0121] (packaging material) The printed material or laminate of the present invention can be used as a multilayer packaging material for the purpose of protecting food, pharmaceuticals, and the like. When used as a multilayer packaging material, the layer configuration may change depending on the contents, usage environment, and usage form. Furthermore, the packaging of the present invention may be appropriately provided with an easy-open treatment or resealing means.

[0122] As an example of the packaging material of the present invention, a laminate having a sealant layer is used. The sealant layer surfaces of the laminate are placed facing each other, and then the peripheral edges are heat-sealed to form a bag. As for the bag-making method, the laminate of the present invention can be folded or placed together so that the inner layer surfaces (sealant layer surfaces) face each other, and the peripheral edges can be heat-sealed in various forms such as side seal type, two-sided seal type, three-sided seal type, four-sided seal type, envelope seal type, gusset seal type, pleated seal type, flat-bottom seal type, square-bottom seal type, gusset type, and other heat-seal types. The packaging material of the present invention can take various forms depending on the contents, usage environment, and usage form. Self-standing packaging materials (standing pouches) are also possible. As for the heat-sealing method, known methods such as bar seal, rotary roll seal, belt seal, impulse seal, high-frequency seal, and ultrasonic seal can be used.

[0123] If the first and second substrates of the printed material or laminate of the present invention do not function as sealant layers that form heat-sealable areas when forming the packaging material, an additional sealant layer may be added. The sealant layer may be made by bonding the additional substrate with the adhesive of the present invention, or it may be an adhesive layer made of the adhesive of the present invention.

[0124] Products using the packaging material of the present invention are manufactured by filling the packaging material with contents through its opening and then heat-sealing the opening. Examples of contents that can be filled include, for example, food products such as rice crackers, bean snacks, nuts, biscuits / cookies, wafers, marshmallows, pies, semi-baked cakes, candies, and snack foods; staple foods such as bread, instant noodles, dried noodles, pasta, aseptically packaged rice, rice porridge, packaged mochi, and cereal foods; processed agricultural products such as pickles, boiled beans, natto, miso, frozen tofu, tofu, enoki mushrooms, konjac, processed wild vegetables, jams, peanut cream, salads, frozen vegetables, and processed potato products; processed livestock products such as ham, bacon, sausages, processed chicken products, and corned beef; and fish ham. Examples of processed seafood products include sausages, processed seafood products, fish cakes, seaweed, preserved foods, dried bonito flakes, salted seafood, smoked salmon, and spicy cod roe; fruits such as peaches, oranges, pineapples, apples, pears, and cherries; vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, and potatoes; frozen and chilled prepared foods such as hamburgers, meatballs, fried seafood, dumplings, and croquettes; dairy products such as butter, margarine, cheese, cream, instant creamy powder, and infant formula; liquid seasonings; retort curry; and pet food.

[0125] Furthermore, as a non-food product, it can be used as a packaging material for various items such as cigarettes, disposable hand warmers, pharmaceuticals such as intravenous fluid packs, liquid laundry detergent, liquid dish soap, liquid bath detergent, liquid bath soap, liquid shampoo, liquid conditioner, cosmetics such as lotions and emulsions, vacuum insulation materials, and batteries. [Examples]

[0126] The present invention will be described in more detail below with reference to specific synthesis examples and embodiments, but the present invention is not limited to these embodiments. In the following examples, "parts" and "%" represent "parts by mass" and "mass%", respectively, unless otherwise specified.

[0127] (Water-based ether-based urethane resin solution - 1) In a nitrogen-purged container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer, the mixture was reacted in a mixed solvent consisting of 191 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 141 parts by mass of isophorone diisocyanate, 26 parts by mass of 2,2-dimethylolpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 200 parts by mass of methyl ethyl ketone to obtain an organic solvent solution of a urethane prepolymer having isocyanate groups at its molecular ends. Next, 20 parts by mass of a 50% potassium hydroxide aqueous solution was added to neutralize some or all of the carboxyl groups of the urethane prepolymer. Then, 700 parts by mass of water and 9.0 parts by mass of an 80% hydrazine aqueous solution were added and thoroughly stirred to obtain an aqueous dispersion of urethane resin. Subsequently, aging and solvent removal were performed to obtain "Aqueous ether-based urethane resin solution-1" with a non-volatile content of 40% by mass.

[0128] (Water-based ether-based urethane resin solution - 2) In a nitrogen-purged container equipped with a thermometer, nitrogen gas introduction tube, and stirrer, a mixed solvent of 256 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 102 parts by mass of isophorone diisocyanate, 23 parts by mass of 2,2-dimethylolpropionic acid, 6.5 parts by mass of neopentyl glycol, and 200 parts by mass of methyl ethyl ketone was reacted to obtain an organic solvent solution of a urethane prepolymer having isocyanate groups at the molecular ends. Next, 18 parts by mass of a 50% potassium hydroxide aqueous solution was added to neutralize some or all of the carboxyl groups of the urethane prepolymer, and then 700 parts by mass of water and 6.5 parts by mass of an 80% hydrazine aqueous solution were added and thoroughly stirred to obtain an aqueous dispersion of urethane resin. Subsequently, aging and desolventing were performed to obtain "Aqueous ether-based urethane resin solution-2" with a non-volatile content of 40% by mass.

[0129] (Water-based ether-based urethane resin solution - 3) In a nitrogen-purged container equipped with a thermometer, nitrogen gas introduction tube, and stirrer, a mixed solvent containing 250 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 109 parts by mass of isophorone diisocyanate, 8.6 parts by mass of 2,2-dimethylolpropionic acid, 26 parts by mass of 1,4-cyclohexanedimethanol, and 200 parts by mass of methyl ethyl ketone was reacted to obtain an organic solvent solution of a urethane prepolymer having isocyanate groups at the molecular ends. Next, 6.8 parts by mass of 50% aqueous potassium hydroxide was added to neutralize some or all of the carboxyl groups of the urethane prepolymer, and then 700 parts by mass of water and 6.9 parts by mass of 80% aqueous hydrazine were added and thoroughly stirred to obtain an aqueous dispersion of urethane resin. Subsequently, aging and desolventing were performed to obtain "Aqueous ether-based urethane resin solution-3" with a non-volatile content of 40% by mass.

[0130] (Water-based ether-based urethane resin solution - 4) In a nitrogen-purged container equipped with a thermometer, nitrogen gas introduction tube, and stirrer, 196 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 145 parts by mass of isophorone diisocyanate, 26 parts by mass of 2,2-dimethylolpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 200 parts by mass of methyl ethyl ketone were reacted in a mixed solvent to obtain an organic solvent solution of a urethane prepolymer having isocyanate groups at the molecular ends. Next, 19 parts by mass of triethylamine were added to neutralize some or all of the carboxyl groups of the urethane prepolymer, and then 700 parts by mass of water and 9.2 parts by mass of 80% aqueous hydrazine solution were added and thoroughly stirred to obtain an aqueous dispersion of urethane resin. Subsequently, aging and desolventing were performed to obtain "Aqueous ether-based urethane resin solution-4" with a non-volatile content of 40% by mass.

[0131] (Water-based ether-based urethane resin solution - 5) In a nitrogen-purged container equipped with a thermometer, nitrogen gas introduction tube, and stirrer, 196 parts by mass of polyoxytetramethylene glycol (molecular weight 2000), 145 parts by mass of isophorone diisocyanate, 26 parts by mass of 2,2-dimethylolpropionic acid, 28 parts by mass of 1,4-cyclohexanedimethanol, and 200 parts by mass of methyl ethyl ketone were reacted in a mixed solvent to obtain an organic solvent solution of a urethane prepolymer having isocyanate groups at the molecular ends. Next, 13 parts by mass of a 25% aqueous ammonia solution was added to neutralize some or all of the carboxyl groups of the urethane prepolymer, and then 700 parts by mass of water and 9.2 parts by mass of an 80% aqueous hydrazine solution were added and thoroughly stirred to obtain an aqueous dispersion of urethane resin. Subsequently, aging and desolventing were performed to obtain "Aqueous ether-based urethane resin solution-5" with a non-volatile content of 40% by mass.

[0132] (Water-based ether-based urethane resin solution - 6) Takelac W-6061, manufactured by Mitsui Chemicals, was prepared as "Water-based ether-based urethane resin solution-6".

[0133] (Water-based ester urethane resin solution) Mitsui Chemicals' "Takelac W-5030" was prepared as an "aqueous ester-based urethane resin solution."

[0134] (Adjustment of anchor coat composition) As anchor coat compositions, aqueous anchor coat varnishes were prepared as Preparation Examples-AC1 to Preparation Examples-AC7 shown in Table 1.

[0135] [Table 1]

[0136] The following ingredients were used in Table 1. Leveling agent: Acetylenediol ethoxylate Defoaming agent: Silicone-based defoaming agent (manufactured by BYK)

[0137] (Adjustment of electron beam-curable yellow ink for offset printing) As an electron beam-curable yellow ink for offset printing, we prepared the EB offset ink shown in Table 2 as an example of preparation.

[0138] [Table 2]

[0139] The following ingredients were used in the table. Acrylates: Acrylate oligomers / acrylate monomers Pigment: Yellow pigment (yellow azo pigment derivative)

[0140] (Preparation of electron beam-curable white ink for flexographic printing) As an electron beam-curable white ink for flexographic printing, we prepared the EB flexo W ink shown in Table 3.

[0141] [Table 3]

[0142] The following ingredients were used in the table. Acrylate: Acrylate oligomer / Acrylate monomer White pigment: Titanium dioxide Dispersant: Pigment dispersant containing acidic groups (manufactured by BYK) Defoaming agent: Silicone-free defoaming agent (manufactured by Evonik)

[0143] (Preparation of electron beam curing OP varnish for flexographic printing) As an electron beam curable OP varnish for flexographic printing, we prepared the EB flexo OP varnish shown in Table 4.

[0144] [Table 4]

[0145] The following ingredients were used in the table. Acrylate: Amine-modified polyether acrylate oligomer / acrylate monomer Leveling agent: Polyether-modified siloxane copolymer (Evonik) Blocking prevention agent: Synthetic amorphous silica (manufactured by Grace Co., Ltd.) Defoaming agent: Silicone-free defoaming agent (manufactured by Evonik)

[0146] (viscosity adjustment) The water-based anchor coat varnish described in the adjustment example was adjusted using a Zaan Cup #4 (manufactured by Rigosha) with water for 10 seconds (25°C).

[0147] (Reverse-printed laminate (printing ink laminate) structure) The reverse-printed laminate (printing ink laminate) was constructed as follows: first printing layer: water-based anchor coat varnish, second printing layer: EB offset ink, third printing layer: EB flexographic W ink.

[0148] (Surface-printed laminate (printing ink laminate) structure) The surface-printed laminate (printing ink laminate) was constructed as follows: first printing layer: water-based anchor coat varnish, second printing layer: EB offset ink, and fourth printing layer: EB flexo OP varnish.

[0149] (Printing method) (First printing layer: Water-based anchor coat varnish) The above-mentioned water-based anchor coat varnish was applied to corona-treated polyethylene terephthalate (PET) film (Toyobo Co., Ltd., Ester E5102, 12 μm thick) or corona-treated nylon (Ny) film (Unitika Ltd., ONM, 15 μm thick) using a Flexiproof100 test printing machine (RK Print Coat Instruments Ltd., Anilox 400 LPI), and then dried with a dryer.

[0150] (Second printing layer: EB offset ink printing) 0.125 cc of the above EB offset ink was placed on an RI tester rubber roller, mixed with a metal roller, and then applied to the above film or first printing layer.

[0151] (Third printing layer: EB flexographic double ink printing) The above EB flexo W ink was applied to the above film or the first or second printing layer using a Flexiproof 100 test printer (manufactured by RK Print Coat Instruments Ltd., using anilox 200 LPI).

[0152] (Fourth printing layer: EB flexo OP varnish printing) The above EB flexo OP varnish was applied to the above film or the first or second printing layer using a Flexiproof 100 test printer (manufactured by RK Print Coat Instruments Ltd., anilox 400 LPI).

[0153] (Irradiation conditions) After forming the reverse-printed or front-printed laminates described in Tables 5 to 8 below, electron beam irradiation was immediately performed using an EB device at an energy intensity of 165,000 eV and an irradiation dose of 30 kGy·m / min. (kilogray).

[0154] The resulting laminate (printing ink laminate) was evaluated as described below.

[0155] (Evaluation item 1: Grain resistance) The ink layer surfaces of the laminate (printed ink laminate) were rubbed back and forth five times, and the degree of separation of the film on the printed surface was visually evaluated. —Evaluation Criteria— 5. The printed film does not separate at all from the film substrate. 4. Less than 20% of the printed film area is separated from the film. 3. The area ratio of the printed film is such that 20% to less than 50% is separated from the film. 2. The area ratio of the printed film is such that 50% to less than 80% is separated from the film. 1. More than 80% of the printed film area is separated from the film.

[0156] (Evaluation item 2: Adhesion) After applying cellophane tape (manufactured by Nichiban Co., Ltd.) to the printed surface of the laminate (printed ink laminate), the tape was quickly peeled off, and the condition of the printed surface was visually evaluated. —Evaluation Criteria— 5. The printed film does not separate at all from the film substrate. 4. Less than 20% of the printed film area is separated from the film. 3. The area ratio of the printed film is such that 20% to less than 50% is separated from the film. 2. The area ratio of the printed film is such that 50% to less than 80% is separated from the film. 1. More than 80% of the printed film area is separated from the film.

[0157] Tables 5 to 8 show the evaluation results for reverse-printed laminates (printing ink laminates) used in Examples 1 to 42 and Comparative Examples 1 to 6, including the presence or absence of water-based anchor coat varnish, EB offset ink, and EB flexo W ink, as well as the evaluation results for front-printed laminates (printing ink laminates) including the presence or absence of water-based anchor coat varnish, EB offset ink, and EB flexo OP varnish.

[0158] [Table 5]

[0159] [Table 6]

[0160] [Table 7]

[0161] [Table 8]

[0162] Based on the results described above, the laminate (printed material) having the aqueous anchor coat varnish of the present invention was able to improve the resistance to rubbing and adhesion to the substrate. Furthermore, by using an ether-based urethane resin in the aqueous anchor coat varnish, the physical properties could be further improved.

Claims

1. An anchor coat composition for printed materials, wherein the anchor coat composition and electron beam-curable ink are printed on a resin substrate in that order, the anchor coat composition containing a urethane resin (A) and an aqueous medium (B), The anchor coat composition is an anchor coat composition in which the urethane resin (A) is a urethane resin which is a reaction product of a polyol containing a polyether polyol and a polyisocyanate.

2. The anchor coat composition according to claim 1, wherein the urethane resin (A) does not contain a polyester polyol as the polyol.

3. The anchor coat composition according to claim 1 or 2, wherein the aqueous medium (B) is water alone, or a mixture of water and an organic solvent miscible with water.

4. The anchor coat composition according to claim 1 or 2, which is an anchor coat composition for printed materials used as packaging material.

5. A printed material formed in the order of a resin substrate, an anchor coat layer, and an electron beam curable ink layer, wherein the anchor coat layer is a layer printed with an anchor coat composition containing a urethane resin (A) and an aqueous medium (B). The urethane resin (A) is a printed material which is a urethane resin that is a reaction product of a polyol containing a polyether polyol and a polyisocyanate.

6. The printed material according to claim 5, to be used as packaging material.

7. The electron beam-curable ink layer is a printed layer printed using a lithographic offset printing method or a flexographic printing method. The printed material according to claim 5 or 6.

8. The electron beam curable ink layer has a colored ink layer and a colorless ink, or a colored ink layer and a white ink layer. The printed material according to claim 5 or 6.

9. A laminate using the printed material described in claim 5.

10. A packaging material using the printed material described in claim 5.

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