Printed matter and laminates

Abstract

This invention provides a printed material having a multilayer film and a printing layer. The multilayer film has at least one layer (A), which is mainly composed of a non-cyclic polyolefin (a1) and contains 10% by mass to 40% by mass of an acid-modified polyolefin resin (a2) modified by an unsaturated carboxylic acid component. The printing layer is formed by printing an aqueous liquid printing ink onto layer (A). According to this invention, a printed material, a packaging material using the printed material, and a laminate for the printed material are provided. The coating of the aqueous liquid printing ink formed by the printing plate-based printing method exhibits excellent adhesion to the polyolefin film, scratch resistance, anti-blocking properties, good transferability, and an excellent appearance.

Description

Technical Field

[0001] The present invention relates to printed matter, packaging material and laminate having a printed layer on at least one side of a polyolefin multilayer film, which is printed by a plate-based printing method and using water-based liquid printing ink. Background Technology

[0002] Generally speaking, in the packaging of goods, for decoration and surface protection, a simple form of printing is used, in which surface printing ink is printed on the surface side of the plastic film that serves as the substrate, while the back side that comes into contact with the goods is not printed (so-called surface printing method).

[0003] In this way, the surface printing ink is printed on the surface of the plastic film that serves as the substrate, so the ink film is directly exposed to the outside, requiring strong film properties during product handling, etc.

[0004] Traditionally, surface printing inks used for printing plates applied to plastic films have utilized inks containing organic solvents. Organic solvents are soluble in plastics, thus promising a certain level of adhesion. However, in recent years, there has been a growing demand for environmentally friendly inks, leading to an increasing need for water-based surface printing inks. Water-based surface printing inks do not use organic solvents, thus effectively reducing carbon dioxide and VOC emissions during printing. However, the resulting prints exhibit reduced adhesion to plastic films, resulting in a decrease in coating properties. In particular, it is difficult to obtain prints with the same adhesion as those using inks containing organic solvents for polyolefin films such as polypropylene and polyethylene.

[0005] To improve the adhesion of surface water-based printing inks, research was conducted on modifying the ink composition (see, for example, Patent Documents 1 and 2). On the other hand, although there are many types of plastic film materials that can be used as substrates, polyolefin films with excellent adhesion to surface water-based printing inks are little known.

[0006] For printed materials that have undergone surface printing, in addition to the basic coating properties such as the adhesion of printing ink, scratch resistance, and anti-blocking, in recent years there has also been a requirement for an appearance that is no less than that of inks using organic solvents. Therefore, it is necessary to develop printed materials that possess these properties.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 2018-76431

[0010] Patent Document 2: Japanese Patent Application Publication No. 2018-131548 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] The problem to be solved by the present invention is to provide a printed material, a packaging material using the printed material, and a laminate for the printed material, wherein the coating of the water-based liquid printing ink formed by the printing material by a plate-based printing method has excellent adhesion to the polyolefin film, abrasion resistance, anti-blocking properties, good transferability, and excellent appearance.

[0013] Methods for solving problems

[0014] That is, the present invention provides a printed material having multiple layers of film and a printing layer.

[0015] The multilayer film has at least one layer (A), which is composed of a polyolefin (a1) without a cyclic structure as the main component and contains 10% by mass to 40% by mass of an acid-modified polyolefin resin (a2) that has been acid-modified by an unsaturated carboxylic acid component. The printing layer is printed on the layer (A) by water-based liquid printing ink.

[0016] In addition, the present invention provides a packaging material using a printed material having a multilayer film and a printing layer, wherein the multilayer film has at least a layer (A), the layer (A) having a non-cyclic polyolefin (a1) as the main component and also containing 10 to 40% by mass of an acid-modified polyolefin resin (a2) modified by an unsaturated carboxylic acid component, and the printing layer is printed on the layer (A) by an aqueous liquid ink.

[0017] In addition, the present invention provides a laminate having at least a multilayer film, wherein the multilayer film has at least a layer (A), the layer (A) having a non-cyclic polyolefin (a1) as the main component and also containing 10 to 40% by mass of an acid-modified polyolefin resin (a2) that has been acid-modified by an unsaturated carboxylic acid component.

[0018] Invention Effects

[0019] According to the present invention, a printed material, a packaging material using the printed material, and a laminate for the printed material can be obtained, wherein the coating of the water-based liquid printing ink formed by the printing plate-based printing method of the printed material has excellent adhesion to the polyolefin film, abrasion resistance, anti-blocking properties, good transferability, and excellent appearance. Detailed Implementation

[0020] <Polyolefin membrane>

[0021] The polyolefin film used in this invention is a multilayer film having at least one layer (A). This layer (A) has a non-cyclic polyolefin (a1) as its main component and also contains 10-40% by mass of an acid-modified polyolefin resin (a2) that has been acid-modified by an unsaturated carboxylic acid component. This layer (A) functions as a support and also functions as a layer for printing water-based liquid printing inks due to its high adhesion to them. It should be noted that in this invention, "as a main component" means that the resin composition containing at least 50% by mass of a specific resin relative to the total amount of the resin composition forming the layer, preferably at least 55% by mass. Furthermore, in this invention, "containing" means that the resin composition containing at least 1% by mass of a specific resin relative to the total amount of the resin composition forming the layer, preferably at least 20% by mass.

[0022] The multilayer film of the present invention is not particularly limited as long as it has a layer (A) as the surface on which the printing layer is formed; for example, it is preferable that layer (A) is laminated with other layers. Specifically, for example, it is preferable that layer (B) is further formed on the surface of layer (A) opposite to the surface on which the printing layer is formed. The structure of layer (B) will be described later.

[0023] (Layer A)

[0024] In this invention, layer (A) uses a non-cyclic polyolefin (a1) as its main component.

[0025] Examples of polyolefin resins (a1) that can be used here include homopolymers or copolymers of α-olefins having 2 to 6 carbon atoms. Regarding the copolymerization form, it can be either a block copolymer or a random copolymer. Furthermore, from the viewpoint of maintaining the appearance of the packaging during molding and suppressing warping of the film itself, a polyolefin resin with a melting point of 110°C or higher is preferred as the polyolefin resin (a1).

[0026] As the aforementioned polyolefin resin (a1), any resin known as a polypropylene resin, polyethylene resin, etc., can be used. Examples of polypropylene resins include propylene homopolymers, propylene-ethylene copolymers, propylene-butene-1 copolymers, propylene-ethylene-butene-1 copolymers, ethylene-propylene block copolymers, and metallocene-catalyst-based polypropylene. These can be used alone or in combination. When the multilayer film is wound into a roller for long-term storage before printing using a printing plate, a crystalline propylene resin is preferred from the viewpoint of preventing adhesion. It should be noted that, in this application, crystallinity refers to a peak value of 0.5 J / g or more in the DSC (differential scanning calorimetry) range of 95–250°C.

[0027] Furthermore, the aforementioned polypropylene resin preferably has a melt flow rate (hereinafter referred to as "MFR at 230°C"; measured at 230°C and 21.18N according to JIS K 7210:1999) of 0.5 to 30.0 g / 10 minutes and a melting point of 120 to 165°C, more preferably an MFR of 2.0 to 15.0 g / 10 minutes and a melting point of 125 to 162°C. If the MFR and melting point are within this range, film shrinkage is minimal even during heat molding of the printed material, thus maintaining the appearance of the printed surface and preventing warping of the medium itself, improving film-forming properties when producing co-extruded multilayer films. Additionally, the density is preferably 0.880 to 0.910 g / cm³. 3 More preferably, it is 0.885–0.905 g / cm³. 3 ].

[0028] Furthermore, in particular, when using a propylene-ethylene block copolymer in the layer (A1), the surface can be modified to a pear-skin texture to suppress wrinkling when the multilayer film is wound into a roll, and adhesion can be reduced when stored in a roll. Here, the propylene-ethylene block copolymer is a resin obtained by block polymerization of propylene and ethylene. For example, examples include propylene-ethylene block copolymers obtained by polymerization of ethylene in the presence of propylene homopolymer, or by polymerization of ethylene and propylene.

[0029] Furthermore, if a mixture of crystalline acrylic resin and ethylene-propylene rubber (hereinafter referred to as "EPR") is used in layer (A1), the surface of layer (A1) can be easily modified into a pear-skin texture. As the crystalline acrylic resin used in this process, a highly versatile propylene homopolymer is preferred. On the other hand, as the EPR used in this process, considering the ability to create an uneven film surface and modify the surface into a pear-skin texture, a weight-average molecular weight of 400,000 to 1,000,000 is preferred, and more preferably, 500,000 to 800,000. Furthermore, considering the ability to uniformly modify the film surface into a pear-skin texture, the EPR content in the mixed resin is preferably in the range of 5% to 35% by mass. Considering ease of extrusion processing, the MFR (230°C) of the mixed resin of the crystalline acrylic polymer and EPR is preferably in the range of 0.5 to 15 g / 10 minutes. It should be noted that the weight-average molecular weight of the EPR mentioned above was calculated using GPC (gel permeation chromatography) after extraction of the mixed resin at 40°C using o-dichlorobenzene as a solvent and a cross-fractionation method. Furthermore, the EPR content in the mixed resin was determined by the amount of EPR extracted after extraction of the mixed resin at 40°C using o-dichlorobenzene as a solvent and a cross-fractionation method.

[0030] There are no particular limitations on the manufacturing method of the above-mentioned crystalline propylene resin and EPR mixed resin. For specific examples, one can include: using a Ziegler-type catalyst, manufacturing propylene homopolymer and ethylene-propylene rubber separately by solution polymerization, slurry polymerization, gas-phase polymerization, etc., and then mixing the two using a mixer; or using a two-step polymerization method, generating propylene homopolymer in the first step and generating EPR in the presence of the polymer in the second step.

[0031] The aforementioned Ziegler-type catalysts are so-called Ziegler-Natta catalysts, which can be exemplified by substances composed of transition metal compounds such as titanium compounds, or catalysts supported on a support such as magnesium compounds, and catalytic promoters such as organoaluminum compounds.

[0032] As the polyethylene-based resin mentioned above (a1-1), ethylene resins such as linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE) can be used. Among them, linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE) are preferred because they readily exhibit suitable ink adhesion.

[0033] The density of the ethylene-based resin is preferably 0.890–0.970 g / cm³. 3 More preferably, it is 0.895–0.965 g / cm³. 3 If the density is within this range, it has moderate rigidity, and the film-forming properties and extrusion suitability of the film are improved.

[0034] Furthermore, the MFR (190°C, 21.18N) of the polyethylene-based resin is preferably 2 to 20 g / 10 minutes, more preferably 3 to 10 g / 10 minutes. If the MFR is within this range, the extrudability of the film is improved, wrinkles that easily occur when winding multilayer films into rolls are suppressed, and the roll-forming properties are excellent. Further, these polyethylene-based resins preferably have a melting point of 110 to 135°C, more preferably 115 to 130°C. If the melting point is within this range, even when heated due to post-printing molding, the film shrinkage is minimal, thus maintaining the appearance of the printed surface and suppressing warping of the film itself. They can be used alone or in combination of two or more.

[0035] The layer (A) of the present invention uses a non-cyclic polyolefin (a1) as the main component. Specifically, it contains 50% by mass or more, preferably 55% by mass or more, and more preferably 60% by mass or more, relative to the total amount of the resin composition forming the layer (A). Because the layer (A) uses a non-cyclic polyolefin (a1) as the main component, it has moderate flexibility and processability, and therefore, the printed material of the present invention can be suitably used as packaging material.

[0036] Layer (A) of the present invention further comprises an acid-modified polyolefin resin (a2) modified with an unsaturated carboxylic acid component. In the acid-modified polyolefin resin (a2), the olefin component, as the main component of the acid-modified polyolefin resin, is not particularly limited, but is preferably an olefin with 2 to 6 carbon atoms, such as ethylene, propylene, isobutylene, 2-butene, 1-butene, 1-pentene, or 1-hexene; mixtures thereof may be used. More preferably, it is an olefin with 2 to 4 carbon atoms, such as ethylene, propylene, isobutylene, or 1-butene; further preferably, it is ethylene or propylene; and most preferably, it is ethylene. Furthermore, the acid-modified polyolefin resin (a2) modified with an unsaturated carboxylic acid component necessarily contains a (meth)acrylate component. Examples of (meth)acrylate components include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, decyl methacrylate, lauryl methacrylate, octyl methacrylate, dodecyl methacrylate, and stearyl methacrylate. From the perspective of ease of acquisition and adhesion, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and hexyl methacrylate are more preferred, and methyl acrylate and ethyl methacrylate are even more preferred. Furthermore, the (meth)acrylate component can be copolymerized with the above-mentioned olefin components, and the method is not limited. Examples of copolymerization states include random copolymerization, block copolymerization, and graft copolymerization (graft modification). (It should be noted that "(meth)acrylate" means "acrylic acid" or "methacrylic acid".)

[0037] Furthermore, the acid-modified polyolefin resin (a2) obtained by acid modification of the unsaturated carboxylic acid component is a substance formed by acid modification of the acid-modified polyolefin resin by the unsaturated carboxylic acid component. As unsaturated carboxylic acid components, in addition to acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, etc., half-esters and half-amides of unsaturated dicarboxylic acids can also be mentioned. Among these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferred, and acrylic acid and maleic anhydride are particularly preferred. Furthermore, the unsaturated carboxylic acid component can be copolymerized with the above-mentioned olefin components, and the method is not limited. For example, random copolymerization, block copolymerization, and graft copolymerization (graft modification) can be mentioned. Specifically, for example, ethylene-acrylic acid copolymers and ethylene-(meth)acrylate-maleic anhydride copolymers can be mentioned. One of them can be used alone, or two or more can be mixed.

[0038] As for the acid modification rate of the acid-modified olefin resin (a2) modified by the unsaturated carboxylic acid component, considering the excellent balance between good adhesion to liquid printing inks, suppression of adhesion when rolling and storing multilayer films, and suppression of appearance defects such as wrinkles after printing, it is preferable to use an acid modification rate of 0.5 to 40%, more preferably 0.5 to 35%, and particularly preferably 0.5 to 30%.

[0039] In the layer (A) of the present invention, relative to the total amount of the resin composition forming layer (A), it contains 10% by mass to 40% by mass of an acid-modified olefin resin (a2) that has been acid-modified by an unsaturated carboxylic acid component. When the proportion of the acid-modified olefin resin (a2) that has been acid-modified by an unsaturated carboxylic acid component is less than 10% by mass, the adhesion to liquid printing ink tends to decrease; on the other hand, when it is greater than 40% by mass, the haze of the film tends to increase and the gloss tends to decrease. Preferably, it is in the range of 15% by mass to 35% by mass, more preferably in the range of 18% by mass to 32% by mass.

[0040] In layer (A) of the present invention, when using resins other than polyolefins (a1) and acid-modified olefin resins (a2) that have been acid-modified by unsaturated carboxylic acid components, for example, one or more of the following can be used: 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), ethylene-methacrylic acid copolymer (EMAA); and ionomers of ethylene-acrylic acid copolymers, ionomers of ethylene-methacrylic acid copolymers, etc.

[0041] When using other resins as described above, their content relative to the total amount of the resin composition forming layer (A) is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0042] (Layer B)

[0043] The multilayer film of the present invention is preferably a laminated film of layer (A) and layer (B). Preferably, layer (B) is further formed on the surface of layer (A) opposite to the surface on which the printed layer is disposed.

[0044] From the perspective of ease of co-extrusion with layer (A), layer (B) is preferably made of a polyolefin resin. As the polyolefin resin used for layer (B), any of the substances exemplified in the polyolefin resin (a1) used for layer (A) described above can be used appropriately. In this case, the polyolefin resins used in layers (A) and (B) can be the same or different. Furthermore, the polyolefin resin used in layer (A2) can be a single substance or a mixture of multiple substances.

[0045] Layer (B) may use resins other than polyolefins. Examples of such resins include, for instance, 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 one or more of the following: ionomers of ethylene-acrylic acid copolymers and ionomers of ethylene-methacrylic acid copolymers.

[0046] When using other resins besides the aforementioned polyolefins, their content relative to the total amount of the resin composition forming layer (A) is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0047] Layer (B) can be a single layer or a multilayer layer consisting of two or more layers. Considering superior rigidity, heat resistance, and processability during secondary processing of the printed material, a single-layer or multilayer film primarily composed of polypropylene or polyethylene resin is preferred, and a two-layer film primarily composed of polyethylene resin is more preferred. In the case of a two-layer structure, a configuration of "the outermost layer on the opposite side of the printed surface / the intermediate layer adjacent to layer (A)" is preferred. The thickness ratio of the outermost layer to the intermediate layer in layer (B) is preferably outermost layer:intermediate layer = 1:9 to 5:5, more preferably 2:8 to 6:4.

[0048] In each of the above layers (A) and (B), antifogging agents, antistatic agents, thermal stabilizers, nucleating agents, antioxidants, lubricants, antiblocking agents, release agents, ultraviolet absorbers, colorants, and other components may be added as needed without compromising the purpose of the present invention. In particular, to impart processability during film forming and packaging suitability when the printed material is made into packaging material, the static and dynamic coefficients of friction of the printing surface of the printing ink are preferably 0.1 to 1.0, more preferably 0.2 to 0.6, and even more preferably 0.3 to 0.5.

[0049] The total thickness of the aforementioned layers (A) and (B) can be adjusted according to the intended use, with the preferred thickness being 10–100 μm, more preferably 20–60 μm, and even more preferably 30–50 μm. Furthermore, the thickness ratio of layer (A) to the total thickness of layer (B) is preferably 5% to 50%, more preferably 10% to 40%, and even more preferably 15% to 30%.

[0050] As a method for stacking the aforementioned layers (A) and (B), a co-extrusion stacking method in which layers (A) and (B) are stacked adjacent to each other is preferred. For example, various co-extrusion methods such as co-extrusion multi-layer die method and feed block method, which use two or more extruders for melt extrusion, are preferred. After stacking layers (A1) and (A2) in a molten state, the layers are processed into long rolls of film by methods such as blowing, T-die / cooling roller method, etc. Co-extrusion method using T-die is more preferred.

[0051] Furthermore, the printing surface of layer (A) is preferably treated to have a wetting tension of 36 mN / m or more, more preferably 38 mN / m or more. If the wetting tension is within this range, the printing adhesion can be further improved. Examples of this surface treatment method include surface oxidation treatments such as corona discharge treatment, plasma treatment, chromic acid treatment, flame treatment, hot air treatment, and ozone / ultraviolet treatment, or surface roughening treatments such as sandblasting, among which corona discharge treatment is preferred.

[0052] The printed matter obtained by the present invention is a printed matter obtained by using water-based liquid ink on the multilayer film obtained above and printing it by a plate-based printing method.

[0053] <Printed Layer>

[0054] The water-based liquid printing ink that forms the printing layer of the present invention is a printing ink printed by a plate-based printing method.

[0055] (Definition of liquid printing ink)

[0056] The printing ink used in this invention is a printing ink produced by a plate-based printing method. It refers to liquid inks suitable for plate-based printing methods, such as gravure printing inks or flexographic printing inks (hereinafter, liquid inks are collectively referred to as liquid printing inks). Preferably, it is gravure printing ink using a gravure plate or flexographic printing ink using a flexographic plate. In the case of water-based printing inks, which are a more preferred embodiment of this invention, gravure printing ink using a gravure plate is called water-based gravure printing ink, and flexographic printing ink using a flexographic plate is called water-based flexographic printing ink.

[0057] High-viscosity inks, such as offset printing inks, which are liquid inks, are not included in the liquid printing inks defined in this invention.

[0058] Specifically, it refers to printing inks with a viscosity of 7 to 25 seconds at 25°C using the Zein Cup #3 manufactured by Lihe Co., Ltd., and a surface tension of 25 to 50 mN / m at 25°C.

[0059] In addition, the liquid printing ink of the present invention does not contain active energy curing components, that is, it is an active energy ray non-reactive liquid ink.

[0060] It should be noted that the term "ink" used in the following description refers to "printing ink".

[0061] (Adhesive resin)

[0062] The liquid printing inks used in this invention are not particularly limited, and can be urethane resins, polyvinyl alcohols, polyvinylpyrrolidones, polyacrylic acid, acrylic-acrylonitrile copolymers, potassium acrylate-acrylonitrile copolymers, vinyl acetate-acrylate copolymers, acrylic-alkyl acrylate copolymers, and other acrylic copolymers commonly used in water-based liquid printing inks; styrene-acrylic resins such as styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methylstyrene-acrylic acid copolymers, styrene-α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylate-alkyl acrylate copolymers; styrene-maleic acid; styrene-maleic anhydride; vinylnaphthalene-acrylic acid copolymers; vinylnaphthalene-maleic acid copolymers; vinyl acetate-ethylene copolymers, vinyl acetate-fatty acid vinyl ester copolymers, vinyl acetate-maleate copolymers, vinyl acetate-crotonic acid copolymers, vinyl acetate-acrylic acid copolymers, and other vinyl acetate copolymers and their salts. These can also be appropriately combined according to the desired physical properties.

[0063] Among these, at least one of acrylic resin or urethane resin is readily available and preferred as the adhesive resin.

[0064] (Acrylic resin)

[0065] There are no particular limitations on the acrylic resins mentioned above; examples include homopolymers or copolymers of (meth)acrylates, and copolymers formed by copolymerizing (meth)acrylates with vinyl monomers that can copolymerize with them. Furthermore, copolymers having an acid value are preferred for imparting water dispersibility and water solubility.

[0066] It should be noted that in this invention, "(meth)acrylate" refers to any one or both of acrylate and methacrylate, and "(meth)acryloyl" refers to any one or both of acryloyl and methacryloyl.

[0067] Examples of (meth)acrylates and vinyl monomers that can copolymerize with (meth)acrylates include: methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, isopropyl (meth)acrylate, isobutyl (meth)acrylate, and other alkyl (meth)acrylates; aromatic (meth)acrylates such as benzyl (meth)acrylate; hydroxyl-containing monomers such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate; and methoxy polyethylene glycol mono(meth)acrylate. Alkyl polyalkylene glycol mono(meth)acrylates, methoxy polypropylene glycol mono(meth)acrylates, etc.; fluorinated (meth)acrylates, such as perfluoroalkyl ethyl methacrylate; styrene, styrene derivatives (p-dimethylsilyl styrene, (p-vinylphenyl) methyl sulfide, p-hexynyl styrene, p-methoxy styrene, p-tert-butyldimethylsiloxy styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, α-methylstyrene, etc.), vinylnaphthalene, vinylanthracene, 1,1-diphenylethylene, and other aromatic ethylenes. Basic compounds; glycidyl (meth)acrylate, epoxy (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylene glycol tetra(meth)acrylate, 2-hydroxy-1,3-diacryloyloxypropane, 2,2-bis[4-(acryloyloxymethoxy)phenyl]propane, 2,2-bis[4-(acryloyloxyethoxy)phenyl]propane, dicyclopentenyl (meth)acrylate, tricyclodecyl (meth)acrylate, tri(acryloyloxyethyl)isocyanurate (Meth)acrylate compounds such as esters, carbamates, and methacrylates; (meth)acrylates containing alkyl amino groups such as dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and dimethylaminopropyl methacrylate; vinylpyridine compounds such as 2-vinylpyridine, 4-vinylpyridine, and naphthylvinylpyridine; and conjugated dienes such as 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, and 1,3-cyclohexadiene. These monomers can be used individually or in combination of two or more.

[0068] In addition, for the purpose of introducing one or more acidic groups selected from the group consisting of carboxyl groups and carboxylate groups formed by neutralization of carboxyl groups by basic compounds, copolymers with acid values ​​can be obtained by copolymerizing (meth)acrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, β-(meth)acryloyloxyethyl succinate monoester, β-(meth)acryloyloxyethyl phthalate monoester, etc., which have carboxyl groups.

[0069] As a copolymer having an acid value, more specifically, it is preferably a copolymer formed by copolymerizing 5 to 60% by mass of a carboxyl-containing free radical polymerizable monomer of general formula (1) with 40 to 95% by mass of a free radical polymerizable monomer capable of copolymerizing with the carboxyl-containing free radical polymerizable monomer.

[0070] [Chemistry 1]

[0071] CH2=C(R 1 )-COO-(R 2 -COO) n -H General formula (1)

[0072] (wherein, R) 1 R is a hydrogen atom or a methyl group. 2 (A substituted or unsubstituted alkylene group having 2 to 18 carbon atoms, where n is an integer from 1 to 10.)

[0073] The carboxyl-containing free radical polymerizable monomers represented by general formula (1) can be specifically exemplified by (meth)acrylic acid, such as acrylic acid, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-acryloyloxyethyl hexahydrophthalic acid and other carboxyl-containing acrylates, methacrylic acid, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid and other carboxyl-containing methacrylates.

[0074] As a free radical polymerizable monomer capable of copolymerizing with the carboxyl-containing free radical polymerizable monomers shown in the above general formula (1), there are no particular limitations, and known free radical polymerizable monomers may be used within the scope that does not hinder the reaction and does not impair the effects of the present invention. Examples include: methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, pentyl methacrylate, heptyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, tridecyl methacrylate, tetradecyl methacrylate, and other vinyl unsaturated monomers containing straight-chain or branched alkyl groups;

[0075] Cyclohexyl methacrylate, isobornyl methacrylate, and other vinyl unsaturated monomers containing alicyclic alkyl groups;

[0076] Aromatic vinyl unsaturated monomers such as styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, m-methylstyrene, vinylnaphthalene, benzyl acrylate, benzyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, phenoxydiethylene glycol acrylate, phenoxydiethylene glycol methacrylate, phenoxytetraethylene glycol acrylate, phenoxytetraethylene glycol methacrylate, phenoxyhexaethylene glycol acrylate, phenoxyhexaethylene glycol methacrylate, phenyl acrylate, and phenyl methacrylate.

[0077] fluorinated alkyl vinyl unsaturated monomers such as trifluoroethyl methacrylate and heptadecafluorodecyl methacrylate;

[0078] (Meth)acrylamide, N-methoxymethyl-(meth)acrylamide, N-ethoxymethyl-(meth)acrylamide, N-propoxymethyl-(meth)acrylamide, N-butoxymethyl-(meth)acrylamide, N-pentoxymethyl-(meth)acrylamide, N,N-di(methoxymethyl)acrylamide, N-ethoxymethyl-N-methoxymethylmethacrylamide, N,N-di(ethoxymethyl)acrylamide, N-ethoxymethyl-N-propoxymethylmethacrylamide, N,N-di(propoxymethyl)acrylamide Acrylamide, N-butoxymethyl-N-(propoxymethyl)methacrylamide, N,N-di(butoxymethyl)acrylamide, N-butoxymethyl-N-(methoxymethyl)methacrylamide, N,N-di(pentoxymethyl)acrylamide, N-methoxymethyl-N-(pentoxymethyl)methacrylamide, N,N-dimethylaminopropylacrylamide, N,N-diethylaminopropylacrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide and other amide-containing vinyl unsaturated monomers;

[0079] Polyethylene glycol mono(meth)acrylate, polyethylene glycol / polypropylene glycol mono(meth)acrylate, methoxy polyethylene glycol mono(meth)acrylate and other vinyl unsaturated monomers containing polyoxyethylene alkyl groups;

[0080] 2-Hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glyceryl mono(meth)acrylate, 4-hydroxyvinylbenzene, 1-ethynyl-1-cyclohexanol, allyl alcohol, and other hydroxyl-containing vinyl unsaturated monomers; etc. One or more of these monomers may be used.

[0081] When introducing acidic groups, it is preferable to adjust the amount of monomer appropriately to make the acid value within the desired range, which will be described in detail later.

[0082] The aforementioned copolymers can be manufactured, for example, by polymerizing various monomers in the presence of a polymerization initiator at a temperature range of 50°C to 180°C, with a temperature range of 80°C to 150°C being more preferred. Examples of polymerization methods include bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization. Furthermore, examples of polymerization types include random copolymers, block copolymers, and graft copolymers.

[0083] The copolymers used in this invention can be core-shell type. In this invention, a core-shell type resin refers to a state in which polymer (a2) is dispersed in an aqueous medium by polymer (a1). Typically, in most cases, polymer (a1) exists on the outermost part of the resin particles, forming the shell, while some or all of polymer (a2) forms the core. Hereinafter, in this invention, the resin forming the shell will be referred to as polymer (a1), and the resin forming the core will be referred to as polymer (a2).

[0084] [The polymer constituting the shell (a1)]

[0085] In the core-shell type resin used in this invention, the polymer constituting the shell (a1) is preferably composed of an acrylic resin containing one or more hydrophilic groups selected from the group consisting of a carboxyl group and a carboxylate group formed by neutralizing the carboxyl group. In this case, the acid value of the shell is preferably in the range of 40 mg KOH / g to 250 mg KOH / g, and more preferably 120 mg KOH / g or less.

[0086] The carboxyl groups of the polymer (a1) constituting the shell are preferably neutralized by an alkaline compound to form carboxylate groups.

[0087] As alkaline compounds that can be used for neutralization, ammonia, triethylamine, morpholine, monoethanolamine, diethylethanolamine, etc. can be used. Considering further improving the coating's resistance to hot water, corrosion, and reagents, ammonia and triethylamine are preferred.

[0088] Regarding the amount of the above-mentioned alkaline compound used, in order to further improve the water dispersion stability of the obtained core-shell resin, it is preferable to use it in a range of [alkaline compound / carboxyl group] = 0.2 to 2 (molar ratio) relative to the total amount of carboxyl groups in the above-mentioned polymer (a1).

[0089] Among the monomers with polymerizable unsaturated double bonds mentioned above, monomers obtained by polymerizing (meth)acrylic acid monomers containing carboxyl groups are preferred. In particular, as the polymer (a1), in order to adjust the glass transition temperature (Tg1) of the polymer (a1) to the range of 20°C to 100°C, and considering excellent film-forming properties and the formation of a coating with excellent resistance to hot water, corrosion and reagents, monomers obtained by combining and polymerizing (meth)acrylic acid, (meth)acrylate, (butyl)acrylic acid, etc., are more preferred.

[0090] [The polymer constituting the core (a2)]

[0091] The polymer (a2) constituting the core can be a copolymer of the same acrylic monomers as the aforementioned acrylic resin.

[0092] At this point, the weight-average molecular weight of the core is preferably in the range of 200,000 to 3,000,000, more preferably 800,000 or more. The temperature Tg is preferably in the range of -30°C to 30°C.

[0093] The polymer (a2) constituting the core can be a copolymer of the same acrylic monomers as the aforementioned acrylic resin, and preferably manufactured using an aqueous medium. Specifically, it can be manufactured by supplying the monomers and polymerization initiators together or sequentially into a reaction vessel containing an aqueous medium for polymerization. In this case, a pre-emulsion can be prepared by mixing the monomers, the aqueous medium, and a reactive surfactant as needed beforehand, and then supplying it, along with the polymerization initiator, into a reaction vessel containing an aqueous medium for polymerization.

[0094] As polymerization initiators that can be used in the manufacture of polymer (a2), free radical polymerization initiators such as persulfate, organic peroxide, and hydrogen peroxide, and azo initiators such as 4,4'-azobis(4-cyanopentanoic acid) and 2,2'-azobis(2-amidinylpropane) dihydrochloride can be used. Furthermore, the aforementioned free radical polymerization initiators can be used in conjunction with the reducing agents described later as redox polymerization initiators.

[0095] As the aforementioned persulfate, potassium persulfate, sodium persulfate, ammonium persulfate, etc., can be used, for example. As the aforementioned organic peroxide, for example, benzoyl peroxide, lauroyl peroxide, decanoyl peroxide, tert-butyl peroxide, dicumyl peroxide, tert-butyl peroxylaurate, tert-butyl peroxybenzoate, cumene hydroperoxide, p-menthane hydroperoxide, tert-butyl hydroperoxide, etc., can be used.

[0096] In addition, as reducing agents as mentioned above, for example, ascorbic acid and its salts, isoascorbic acid and its salts (sodium salts, etc.), tartaric acid and its salts, citric acid and its salts, metal salts of formaldehyde hyposulfite, sodium thiosulfate, sodium bisulfite, ferric chloride, etc. can be used.

[0097] Regarding the amount of polymerization initiator used, only an amount sufficient for smooth polymerization is required. From the viewpoint of maintaining excellent corrosion resistance of the obtained coating, the less the better. It is preferably set to 0.01% to 0.5% by mass relative to the total amount of monomers used in the manufacture of the vinyl polymer (a2). Furthermore, when the above-mentioned polymerization initiator and the above-mentioned reducing agent are used together, their combined amount is also preferably within the above range.

[0098] In addition, reactive surfactants, anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, etc., can be used when manufacturing the above-mentioned preemulsion.

[0099] Regarding the acid value of the above copolymer, it is preferred to have an acid value of 20 mg KOH / g or higher and 120 mg KOH / g or lower, and more preferably an acid value of 25 mg KOH or higher. If the acid value is 20 mg KOH / g or higher, the abrasion resistance, water abrasion resistance, and scratch resistance of the laminate can be improved when a curing agent is added.

[0100] It should be noted that the acid value mentioned here refers to the number of milligrams of potassium hydroxide required to neutralize the acidic components contained in 1g of the resin.

[0101] The weight-average molecular weight of the above copolymer is preferably in the range of 5,000 to 100,000. If the weight-average molecular weight is 5,000 or higher, there is a tendency for the heat resistance of the resin film not to decrease, and for the laminate to maintain its abrasion resistance and water abrasion resistance. If it is 100,000 or lower, there is a tendency for the laminate to have both substrate adhesion and scratch resistance.

[0102] The glass transition temperature (Tg) of the above copolymer is preferably in the range of 0°C to 55°C. If the Tg of the above copolymer is above 0°C, the film strength is maintained and the water abrasion resistance of the laminate does not decrease. In addition, if it is below 55°C, there is a tendency for the compatibility with other printed layers to not decrease, and the abrasion resistance, water abrasion resistance, and scratch resistance of the laminate to be well maintained.

[0103] It should be noted that the glass transition temperature (Tg1) mentioned above refers to the so-called calculated glass transition temperature, which is the value calculated by the following method.

[0104] (Equation 1) 1 / Tg(K)=(W1 / T1)+(W2 / T2)+···(Wn / Tn)

[0105] (Equation 2) Tg(℃)=Tg(K)-273

[0106] In Equation 1, W1, W2, ..., Wn represent the mass percentage of each monomer relative to the total mass of monomers used in the manufacture of the polymer, and T1, T2, ..., Tn represent the glass transition temperature (K) of the homopolymer of each monomer. It should be noted that the values ​​of T1, T2, ..., Tn are those described in the Polymer Handbook (Fourth Edition, edited by J. Brandrup, E. Himmergut, and E.A. Grulke).

[0107] Furthermore, the glass transition temperatures of the homopolymers of each monomer, which are not listed in the aforementioned polymer handbook, were determined using a differential scanning calorimeter "DSC Q-100" (manufactured by TA Instruments) according to the method in JIS K 7121. Specifically, for polymers in which the solvent was completely removed by vacuum aspiration, the heat change was measured in the range of -100°C to +200°C at a heating rate of 20°C / min. The point where the straight line extending from each baseline at equal distances along the vertical axis intersects the curve of the step-like change in glass transition temperature was defined as the glass transition temperature.

[0108] (Carbamate resin)

[0109] Examples of urethane resins include those obtained by reacting polyols such as polyether polyols, polyester polyols, and polycarbonate polyols, as well as polyols having hydrophilic groups that are anionic, cationic, polyoxyethylene, or polyoxyethylene-polyoxypropylene groups, with polyisocyanates. Furthermore, the weight-average molecular weight of the aforementioned urethane resins is not particularly limited, and is generally acceptable as long as it is between 5,000 and 200,000, more preferably between 20,000 and 150,000.

[0110] Examples of the aforementioned polyether polyols include: ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, glycerol, trimethylolethane, trimethylolpropane, sorbitol, sucrose, aconitine, triphenyltriic acid, phosphoric acid, ethylenediamine, diethylenetriamine, triisopropanolamine, pyrogallol, dihydroxybenzoic acid, hydroxyphthalic acid, 1,2,3-propanetrithiol, and other compounds having two or more active hydrogen groups, which are polymerized with cyclic ether compounds such as ethylene oxide, propylene oxide, butane oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, and cyclohexene; or substances formed by ring-opening polymerization of the aforementioned cyclic ether compounds using cationic catalysts, protic acids, Lewis acids, etc. as catalysts.

[0111] The aforementioned polyester polyols can be obtained through dehydration condensation reactions of diol compounds, dicarboxylic acids, hydroxycarboxylic acid compounds, etc., ring-opening polymerization reactions of cyclic ester compounds such as ε-caprolactone, and copolymerization of polyesters obtained through these reactions. Examples of diol compounds used as raw materials for the aforementioned polyester polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, dihydroxyethoxybenzene, 1,4-cyclohexanediol, 1,4-cyclohexanediol, bisphenol A, hydrogenated bisphenol A, hydroquinone, and their epoxide adducts.

[0112] In addition, dicarboxylic acids that can be used as raw materials for the aforementioned polyester polyols include, for example, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalenedicarboxylic acid, biphenyl dicarboxylic acid, and 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid.

[0113] Examples of hydroxycarboxylic acids that can be used as raw materials for the aforementioned polyester polyols include p-hydroxybenzoic acid and p-(2-hydroxyethoxy)benzoic acid.

[0114] As a polycarbonate polyol, for example, a substance obtained by reacting a carbonate with a low molecular weight polyol, preferably a straight-chain aliphatic diol, can be used.

[0115] As the aforementioned carbonates, methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclic carbonate, diphenyl carbonate, etc., can be used.

[0116] As low molecular weight polyols that can react with the above-mentioned carbonates, examples include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,5-hexanediol, 2,5-hexanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, and 1,9-nonanediol. Lower molecular weight dihydroxy compounds such as 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,4-cyclohexanediol, 1,4-cyclohexanediol, hydroquinone, resorcinol, bisphenol-A, bisphenol-F, and 4,4'-biphenol; polyether polyols such as polyethylene glycol, polypropylene glycol, and polyoxytetramethylene glycol; and polyester polyols such as polyhexamethylene adipate, polyhexamethylene succinate, and polycaprolactone.

[0117] The polycarbonate structure is preferably used in the range of 10% to 90% by mass relative to the total mass of the polyol and the polyisocyanate used in the manufacture of the polycarbonate-based urethane resin.

[0118] Furthermore, considering the dispersibility and stability imparted to water-based liquid printing inks, the aforementioned urethane resin possesses a hydrophilic group. As this hydrophilic group, groups referred to as anionic, cationic, or nonionic groups can generally be used, with anionic and cationic groups being preferred.

[0119] As the aforementioned anionic group, carboxyl groups, carboxyl groups, sulfonic acid groups, sulfonate groups, etc., can be used. Among them, considering the maintenance of good water dispersibility, it is preferable to use carboxyl groups or sulfonate groups that are partially or completely neutralized by alkaline compounds, etc.

[0120] Examples of basic compounds that can be used to neutralize the carboxyl and sulfonic acid groups, which are the aforementioned anionic groups, include organic amines such as ammonia, triethylamine, pyridine, and morpholine; alkanolamines such as monoethanolamine; and metal alkali compounds containing Na, K, Li, Ca, etc.

[0121] Furthermore, tertiary amino groups, for example, can be used as the aforementioned cationic group. Acids that can be used to neutralize part or all of the aforementioned tertiary amino groups, for example, formic acid, acetic acid, etc., can be used. Additionally, quaternizing agents that can be used to quaternize part or all of the aforementioned tertiary amino groups, for example, dialkyl sulfate esters such as dimethyl sulfate, diethyl sulfate, etc., can be used.

[0122] Furthermore, as the aforementioned nonionic group, polyoxyethylene, polyoxypropylene, polyoxybutene, poly(oxyethylene-oxypropylene) group, and polyoxyethylene-polyoxypropylene group, etc., can be used as polyoxyalkylene groups. Among these, from the perspective of further improving hydrophilicity, polyoxyalkylene groups having oxyethylene units are preferred.

[0123] When the hydrophilic group is present in the total amount of the above-mentioned urethane resin at 0.5% to 30% by mass, it imparts better water dispersibility, and more preferably in the range of 1% to 20% by mass.

[0124] Furthermore, the crosslinking agent described later can be used according to the desired physical properties. When using the above-mentioned crosslinking agent, it is preferable to use a substance having functional groups that can undergo crosslinking reactions with the functional groups of the above-mentioned crosslinking agent as the urethane resin.

[0125] Examples of such functional groups include carboxyl groups and carboxyl groups, which can function as the hydrophilic groups. These carboxyl groups contribute to the water dispersion stability of urethane resins in aqueous media, and they also function as functional groups during crosslinking reactions, enabling them to participate in a portion of the crosslinking reaction of the crosslinking agent.

[0126] When using carboxyl groups or the like as the aforementioned functional groups, the urethane resin preferably has an acid value of 2 to 55, and from the perspective of improving strength, a substance with an acid value of 15 to 50 is preferred. It should be noted that the acid value mentioned in this invention is a theoretical value calculated based on the amount of acid-containing compounds such as carboxyl-containing polyols used in the manufacture of the aforementioned urethane resin.

[0127] The aforementioned urethane resin can be manufactured, for example, by reacting a polyol with a polyisocyanate and a chain extender as needed.

[0128] Polyamines, other compounds containing active hydrogen atoms, etc., can be used as the aforementioned chain extenders.

[0129] For example, diamines such as ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophorone diamine, 4,4'-dicyclohexylmethyldiamine, 3,3'-dimethyl-4,4'-dicyclohexylmethyldiamine, and 1,4-cyclohexanediamine can be used as polyamines; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, and N-ethylaminoethylamine can also be used. ethylamine, N-methylaminopropylamine; diethylenetriamine, dipropylenetriamine, triethylenetetramine; hydrazine, N,N'-dimethylhydrazine, 1,6-hexamethylenedihydrazine; succinic dihydrazide, adipate dihydrazide, glutarate dihydrazide, sebacic dihydrazide, isophthalic dihydrazide; β-aminourea propionic hydrazide, 3-aminourea-propyl-nitrile carbamate, aminourea-3-aminourea-methyl-3,5,5-trimethylcyclohexane, preferably ethylenediamine.

[0130] Other compounds containing active hydrogen, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, neopentyl glycol, sucrose, methylene glycol, glycerol, sorbitol, and other diols; phenols such as bisphenol A, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfone, hydrogenated bisphenol A, hydroquinone, and others; and water, etc.

[0131] Regarding the aforementioned chain extender, it is preferable to use it in a range where the equivalent amount of the amino groups and groups containing active hydrogen atoms in the chain extender is 1.9 or less (equivalent ratio) relative to the equivalent amount of isocyanate groups in the urethane prepolymer obtained by reacting the polyol with the polyisocyanate, more preferably in a range of 0.0 to 1.0 (equivalent ratio), and even more preferably in a range of 0.5% by mass.

[0132] The chain extender described above can be used during or after the reaction of the polyol with the polyisocyanate. Additionally, the chain extender can also be used when dispersing the obtained urethane resin in an aqueous medium to achieve water-based processing.

[0133] In addition to the polyols mentioned above, examples of lower molecular weight polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, dihydroxyethoxybenzene, 1,4-cyclohexanediol, 1,4-cyclohexanediol, bisphenol A, hydrogenated bisphenol A, hydroquinone and their epoxide adducts, glycerol, trimethylolethane, trimethylolpropane, sorbitol, pentaerythritol, etc. These polyols can be used alone or in combination of two or more.

[0134] As a polyisocyanate that reacts with the above-mentioned polyols to form a urethane resin, for example, aromatic diisocyanates such as phenyl diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and naphthalene diisocyanate, and aliphatic or diisocyanates containing aliphatic cyclic structures such as hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, phenyl diisocyanate, and tetramethylphenyl diisocyanate can be used alone or in combination of two or more.

[0135] The copolymer described above functions as an adhesive resin.

[0136] The adhesive resin, calculated based on the solid content of the water-based liquid printing ink of the present invention, is preferably 5 to 50% by mass. If it is 5% by mass or more, the ink film strength does not decrease, and the substrate adhesion, water rubbing resistance, etc., are also well maintained. On the other hand, if it is 50% by mass or less, the reduction in tinting strength can be suppressed, and high viscosity is avoided, and the workability does not decrease. More preferably, it is 10 to 40% by mass, and most preferably, it is 15 to 35% by mass.

[0137] Furthermore, the copolymer is preferably 10 to 40% by mass, more preferably 20 to 30% by mass, based on the solid content of all adhesive resins.

[0138] (Coloring agent)

[0139] The liquid printing ink used in this invention contains a colorant. Examples of colorants include dyes, inorganic pigments, and organic pigments used in general inks, coatings, and recording agents. Among these, inorganic pigments and organic pigments are preferred.

[0140] As organic pigments, examples include soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, anthraquinone-anthraquinone, bianthraquinone, anthraquinone, perylene, perinone, quinacridone, thioindole, dioxazine, isoindolineone, quinolineone, azomethylazo, flavanone, diketopyrrolopyrrole, isoindoline, indanone, and carbon black pigments. In addition, examples include Carmine 6B, Lake Red C, Permanent Red 2B, Diazo Yellow, Pyrazolone Orange, Carmine FB, Cromophtal Yellow, Cromophtal Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Fuchsin, Quinacridone Red, Indanone Blue, Pyrimidine Yellow, Thioninzae Margaritamine, Thioninzae Fuchsin, Perylene Red, Pyrene Orange, Isoindolinone Yellow, Aniline Black, Diketopyrrolopyrrole Red, and daylight fluorescent pigments. Furthermore, both untreated and acid-treated pigments can be used. Specific examples of preferred organic pigments are given below.

[0141] Examples of black pigments include CI Pigment Black 1, CI Pigment Black 6, CI Pigment Black 7, CI Pigment Black 9, and CI Pigment Black 20.

[0142] Examples of blue pigments include CI Pigment Blue 15, CI Pigment Blue 15:1, CI Pigment Blue 15:2, CI Pigment Blue 15:3, CI Pigment Blue 15:4, CI Pigment Blue 15:5, CI Pigment Blue 15:6, CI Pigment Blue 16, CI Pigment Blue 17:1, CI Pigment Blue 22, CI Pigment Blue 24:1, CI Pigment Blue 25, CI Pigment Blue 26, CI Pigment Blue 60, CI Pigment Blue 61, CI Pigment Blue 62, CI Pigment Blue 63, CI Pigment Blue 64, CI Pigment Blue 75, CI Pigment Blue 79, and CI Pigment Blue 80.

[0143] Examples of green pigments include CI Pigment Green 1, CI Pigment Green 4, CI Pigment Green 7, CI Pigment Green 8, CI Pigment Green 10, and CI Pigment Green 36.

[0144] Examples of red pigments include CI Pigment Red 1, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 4, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 8, CI Pigment Red 9, CI Pigment Red 10, CI Pigment Red 11, CI Pigment Red 12, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 17, CI Pigment Red 18, CI Pigment Red 19, CI Pigment Red 20, CI Pigment Red 21, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 31, CI Pigment Red 32, CI Pigment Red 38, CI Pigment Red 41, and C. I Pigment Red 43, CI Pigment Red 46, CI Pigment Red 48, CI Pigment Red 48:1, CI Pigment Red 48:2, CI Pigment Red 48:3, CI Pigment Red 48:4, CI Pigment Red 48:5, CI Pigment Red 48:6, CI Pigment Red 49, CI Pigment Red 49:1, CI Pigment Red 49:2, CI Pigment Red 49:3, CI Pigment Red 52, CI Pigment Red 52:1, CI Pigment Red 52:2, CI Pigment Red 53, CI Pigment Red 53:1, CI Pigment Red 53:2, CI Pigment Red 53:3, CI Pigment Red 54, CI Pigment Red 57, C I Pigment Red 57:1, CI Pigment Red 58, CI Pigment Red 58:1, CI Pigment Red 58:2, CI Pigment Red 58:3, CI Pigment Red 58:4, CI Pigment Red 60:1, CI Pigment Red 63, CI Pigment Red 63:1, CI Pigment Red 63:2, CI Pigment Red 63:3, CI Pigment Red 64:1, CI Pigment Red 68, CI Pigment Red 68, CI Pigment Red 81:1, CI Pigment Red 83, CI Pigment Red 88, CI Pigment Red 89, CI Pigment Red 95, CI Pigment Red 112, CI Pigment Red 114, CI Pigment Red 119, CI Pigment Red Red 122, CI Pigment Red 123, CI Pigment Red 136, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 147, CI Pigment Red 149, CI Pigment Red 150, CI Pigment Red 164, CI Pigment Red 166, CI Pigment Red 168, CI Pigment Red 169, CI Pigment Red 170, CI Pigment Red 171, CI Pigment Red 172, CI Pigment Red 175, CI Pigment Red 176, CI Pigment Red 177, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 180, CI Pigment Red 181, CI Pigment Red 182, C.I. Pigment Red 183, CI Pigment Red 184, CI Pigment Red 185, CI Pigment Red 187, CI Pigment Red 188, CI Pigment Red 190, CI Pigment Red 192, CI Pigment Red 193, CI Pigment Red 194, CI Pigment Red 200, CI Pigment Red 202, CI Pigment Red 206, CI Pigment Red 207, CI Pigment Red 208, CI Pigment Red 209, CI Pigment Red 210, CI Pigment Red 211, CI Pigment Red 213, CI Pigment Red 214, CI Pigment Red 216, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red 220, CI Pigment Red 221, CI Pigment Red 223, CI Pigment Red 224, CI Pigment Red 226, CI Pigment Red 237, CI Pigment Red 238, CI Pigment Red 239, CI Pigment Red 240, CI Pigment Red 242, CI Pigment Red 245, CI Pigment Red 247, CI Pigment Red 248, CI Pigment Red 251, CI Pigment Red 253, CI Pigment Red 254, CI Pigment Red 255, CI Pigment Red 256, CI Pigment Red 257, CI Pigment Red 258, CI Pigment Red 260, CI Pigment Red 262, CI Pigment Red 263, CI Pigment Red 264, CI Pigment Red 266, CI Pigment Red 268, CI Pigment Red 269, CI Pigment Red 270, CI Pigment Red 271, CI Pigment Red 272, CI Pigment Red 279, etc.

[0145] Examples of purple pigments include CI pigment violet 1, CI pigment violet 2, CI pigment violet 3, CI pigment violet 3:1, CI pigment violet 3:3, CI pigment violet 5:1, CI pigment violet 13, CI pigment violet 19 (γ type, β type), CI pigment violet 23, CI pigment violet 25, CI pigment violet 27, CI pigment violet 29, CI pigment violet 31, CI pigment violet 32, CI pigment violet 36, CI pigment violet 37, CI pigment violet 38, CI pigment violet 42, CI pigment violet 50, etc.

[0146] Examples of yellow pigments include CI Pigment Yellow 1, CI Pigment Yellow 3, CI Pigment Yellow 12, CI Pigment Yellow 13, CI Pigment Yellow 14, Pigment Yellow 17, CI Pigment Yellow 24, CI Pigment Yellow 42, CI Pigment Yellow 55, CI Pigment Yellow 62, CI Pigment Yellow 65, CI Pigment Yellow 74, CI Pigment Yellow 83, CI Pigment Yellow 86, CI Pigment Yellow 93, CI Pigment Yellow 94, CI Pigment Yellow 95, CI Pigment Yellow 109, CI Pigment Yellow 110, CI Pigment Yellow 117, and CI Pigment Yellow 109. Yellow 120, Pigment Yellow 125, CI Pigment Yellow 128, CI Pigment Yellow 129, CI Pigment Yellow 137, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 147, CI Pigment Yellow 148, CI Pigment Yellow 150, CI Pigment Yellow 151, CI Pigment Yellow 153, CI Pigment Yellow 154, CI Pigment Yellow 155, CI Pigment Yellow 166, CI Pigment Yellow 168, CI Pigment Yellow 174, CI Pigment Yellow 180, CI Pigment Yellow 185 and CI Pigment Yellow 213, etc.

[0147] Examples of orange pigments include CI Pigment Orange 5, CI Pigment Orange 13, CI Pigment Orange 16, CI Pigment Orange 34, CI Pigment Orange 36, CI Pigment Orange 37, CI Pigment Orange 38, CI Pigment Orange 43, CI Pigment Orange 51, CI Pigment Orange 55, CI Pigment Orange 59, CI Pigment Orange 61, CI Pigment Orange 64, CI Pigment Orange 71, or CI Pigment Orange 74.

[0148] Examples of brown pigments include CI Pigment Brown 23, CI Pigment Brown 25, and CI Pigment Brown 26.

[0149] Among them, CI Pigment Black 7, as a preferred pigment, can be cited as an example.

[0150] CI Pigment Blue 15, CI Pigment Blue 15:1, CI Pigment Blue 15:2, CI Pigment Blue 15:3, CI Pigment Blue 15:4, CI Pigment Blue 15:6 are used as blue pigments.

[0151] CI pigment Green 7 is a green pigment.

[0152] CI Pigment Red 57:1, CI Pigment Red 48:1, CI Pigment Red 48:2, CI Pigment Red 48:3, CI Pigment Red 146, CI Pigment Red 242, CI Pigment Red 185, CI Pigment Red 122, CI Pigment Red 178, CI Pigment Red 149, CI Pigment Red 144, and CI Pigment Red 166 are used as red pigments.

[0153] CI pigments Violet 23 and Violet 37 are used as purple pigments.

[0154] CI Pigment Yellow 83, CI Pigment Yellow 14, CI Pigment Yellow 180, and CI Pigment Yellow 139 are yellow pigments.

[0155] CI pigments used as orange pigments include CI orange 38, CI orange 13, CI orange 34, and CI orange 64.

[0156] It is preferable to use at least one or more pigments selected from the group consisting of these pigments.

[0157] Examples of inorganic pigments include titanium dioxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silicon dioxide, lithopone, antimony white, and gypsum. Among these, titanium dioxide is particularly preferred. Titanium dioxide is white and is preferred considering its tinting strength, hiding power, reagent resistance, and weather resistance. From a printability perspective, it is preferably treated with silicon dioxide and / or aluminum oxide.

[0158] As inorganic pigments other than white, examples include aluminum particles, mica, bronze powder, chrome vermilion, chrome yellow, cadmium yellow, cadmium red, ultramarine, navy blue, iron oxide, iron oxide yellow, iron black, and zirconium. Aluminum is in powder or paste form. From the perspective of processability and safety, it is preferred to use it in paste form. Whether to use a leafing or non-leafing type can be appropriately selected based on the brightness and concentration.

[0159] The average particle size of the above-mentioned pigments is preferably in the range of 10 to 200 nm, and more preferably around 50 to 150 nm.

[0160] The pigments described above are preferably used in an amount sufficient to ensure the concentration and tinting strength of the liquid printing ink used in this invention, i.e., 1 to 60% by weight relative to the total weight of the liquid printing ink used in this invention, and 10 to 90% by weight of the solid components in the ink. Furthermore, these pigments can be used alone or in combination of two or more.

[0161] In addition, pigments can be pre-dispersed using commercially available pigment dispersants to prepare high-concentration pigment dispersions for use in ink production.

[0162] (surfactant)

[0163] The liquid printing ink used in this invention may also contain surfactants depending on the desired physical properties. There are no particular limitations on the surfactant; surfactants commonly used in this art can be used, with alkyne-based surfactants and alcohol alkoxylate-based surfactants being preferred.

[0164] Specifically, examples of alkyne-based surfactants used in this invention include 2,5-dimethyl-3-hexyn-2,5-diol, 3,6-dimethyl-4-octyyn-3,6-diol, 2,4,7,9-tetramethyl-5-decyn-4,7-diol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3-hexyn-2,5-diol, and 2-butyn-1,4-diol. Additionally, commercially available products include unmodified alkane-based alkyne diol surfactants such as Surfynol 61, 82, and 104 (all manufactured by Air Products).

[0165] Surfynol 420, 440, 465, 485, TG, 2502, Dynol 604, 607 (all manufactured by Air Products), Surfynol SE, MD-20, Olfine E1004, E1010, PD-004, EXP4300, PD-501, PD-502, SPC (all manufactured by Nissin Chemical Industry Co., Ltd.), Acetylenol EH, E40, E60, E81, E100, E200 (all manufactured by Kawaken Seika Co., Ltd.), and other epoxy alkane-modified alkynyl glycol surfactants are preferred.

[0166] In addition, DYNWET800 (manufactured by BYK Chemical Japan Co., Ltd.) is a specific example of an alcohol alkoxylated surfactant used in this invention.

[0167] These alkyne-based surfactants and alcohol alkoxylate-based surfactants can be used individually or in combination of two or more.

[0168] The total amount of these alkyne-based surfactants and / or alcohol alkoxylated surfactants added is preferably 0.1% to 1% by mass of the total ink. These alkyne-based surfactants can be used alone or in combination of two or more. If the total amount of alkyne-based surfactants and / or alcohol alkoxylated surfactants added is 0.1% or more of the total ink, the coatability with the substrate is improved, and adhesion to the substrate is maintained. If the total amount of alkyne-based surfactants and / or alcohol alkoxylated surfactants added is less than 1% by mass of the total ink, the abrasion resistance, water resistance, and scratch resistance do not decrease.

[0169] Furthermore, other acrylic polymer surfactants (such as POLYFLOW WS-314 manufactured by Kyoeisha Chemical Co., Ltd.) or modified silicone surfactants (such as POLYFLOW KL-401 manufactured by Kyoeisha Chemical Co., Ltd.) can be used as needed.

[0170] For the reasons stated above, the total amount of surfactant used is preferably 0.1 to 1% of the total ink mass.

[0171] (wax)

[0172] In this invention, wax can be added according to the desired physical properties. Carbon-based waxes are preferred, and examples of carbon waxes include liquid paraffin, natural paraffin, synthetic paraffin, microcrystalline wax, polyethylene wax, fluorocarbon wax, ethylene-propylene copolymer wax, tetrafluoroethylene resin wax, Fischer-Tropsch wax, etc. These waxes can be used alone or in combination of two or more. The total amount of these waxes added is preferably 0.5% to 5% by mass of the total ink. If the total amount of wax added is 0.5% by mass or more of the total ink, abrasion resistance, water abrasion resistance, and scratch resistance can be maintained. If the total amount of wax added is less than 5% by mass of the total ink, adhesion to the substrate, abrasion resistance, water abrasion resistance, and scratch resistance can be maintained.

[0173] (Curing agent)

[0174] In this invention, a curing agent may be added depending on the desired physical properties. There are no particular limitations on the curing agent, which can react with the acid used in this invention; known curing agents that can react with acid groups and are suitable for use in aqueous media can be used. Examples include epoxy-based curing agents, carbodiimide-based curing agents, and oxazoline-based curing agents.

[0175] The aforementioned epoxy curing agents are not particularly limited as long as they are compounds having at least one epoxy group. Examples of epoxy curing agents include bisphenol A diglycidyl ether, modified bisphenol A diglycidyl ether, phenolic varnish glycidyl ether, glycerol polyglycidyl ether, and polyglycerol polyglycidyl ether epoxy resins.

[0176] The aforementioned carbodiimide-based curing agents are not particularly limited as long as they are compounds having at least one carbodiimide group (-N=C=N-). Preferably, the carbodiimide-based curing agent is a polycarbodiimide compound having at least two carbodiimide groups.

[0177] The aforementioned oxazoline-based curing agents are not particularly limited to compounds having an oxazoline skeleton. Specifically, examples of oxazoline-based curing agents include the EPOCROS series manufactured by Nippon Shokubai Co., Ltd.

[0178] Examples of the aforementioned epoxy compounds include diglycidyl ether of bisphenol A and its oligomers, diglycidyl ether of hydrogenated bisphenol A and its oligomers, diglycidyl phthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl p-hydroxybenzoate, diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, diglycidyl succinate, diglycidyl adipate, diglycidyl sebacate, and diglycidyl glycol. Ethers, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, as well as polyalkylene glycol diglycidyl ethers, trimellitic acid triglycidyl ester, isocyanuric acid triglycidyl ester, 1,4-diglycidyloxybenzene, diglycidylpropene, glycerol triglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, and triglycidyl ethers of glycerol epoxide alkane adducts, etc.

[0179] The amount of curing agent added in this invention, calculated based on the total solid content of the ink, is preferably 0.1 to 10.0% by mass, more preferably 0.5 to 9.0% by mass.

[0180] If the amount added is 0.1% by mass or more, it will have the effect of a curing agent. On the other hand, if it is 10.0% by mass or less, it tends to maintain the adhesion, abrasion resistance and water abrasion resistance of the substrate.

[0181] In addition to the above, this invention may also include extender pigments, pigment dispersants, leveling agents, defoamers, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, flame retardants, etc. Among them, fatty acid amides such as oleamide, stearamide, and erucamide, which impart abrasion resistance and smoothness, as well as silicone-based and non-silicone-based defoamers, which suppress foaming during printing, and various dispersants that improve the wettability of pigments, are useful.

[0182] (Manufacturing method of liquid printing ink)

[0183] The liquid printing ink used in this invention can be obtained as follows: a pigment dispersion is obtained by pre-dispersing a mixture containing pigments, aqueous media, dispersants, defoamers, etc., using a disperser. The obtained pigment dispersion is then mixed with the aforementioned copolymer, aqueous media, and additives such as leveling agents as needed.

[0184] As a disperser, it is manufactured using bead mills, Eiger mills, sand mills, Gamma mills, grinders, etc., which are commonly used in the manufacture of gravure and flexographic printing inks.

[0185] When the liquid printing ink of the present invention is used as an aqueous flexographic printing ink, its viscosity is only 7 to 25 seconds at 25°C using a Zein cup #4 manufactured by a lithographic press, and more preferably 10 to 20 seconds. Furthermore, the surface tension of the resulting flexographic ink at 25°C is preferably 25 to 50 mN / m, and more preferably 33 to 43 mN / m. As the surface tension of the ink decreases, the wettability of the ink to substrates such as films increases. However, if the surface tension is below 25 mN / m, due to the wetting spread of the ink, adjacent dots on the screen tend to easily connect, easily becoming a cause of printing surface contamination known as dot bridges. On the other hand, if the surface tension is above 50 mN / m, the wettability of the ink to substrates such as films decreases, easily becoming a cause of depressions.

[0186] When the liquid printing ink used in this invention is used as an aqueous gravure printing ink, its viscosity is only 7 to 25 seconds at 25°C using a Zein cup #3 manufactured by Lihe Co., Ltd., and more preferably 10 to 20 seconds. Furthermore, the surface tension of the obtained gravure ink at 25°C is preferably 25 to 50 mN / m, similar to that of flexographic inks, and more preferably 33 to 43 mN / m. As the surface tension of the ink decreases, its wettability to substrates such as films increases. However, if the surface tension is below 25 mN / m, due to the wetting spread of the ink, adjacent dots on the screen tend to easily connect, easily becoming a cause of printing surface contamination known as dot bridges. On the other hand, if the surface tension is above 50 mN / m, the wettability of the ink to substrates such as films decreases, easily causing depressions.

[0187] (Printed materials)

[0188] In this invention, a printed material is obtained by forming a printed layer by printing the aforementioned liquid printing ink onto the aforementioned polyolefin film. Typically, the ink is applied to the substrate using gravure or flexographic printing methods, and then dried and fixed using an oven to obtain the printed layer. The drying temperature is typically around 40–60°C.

[0189] In this invention, considering factors such as registration stability, high-speed printing suitability, and printing reproducibility, flexographic printing is preferred for printing liquid printing inks.

[0190] Flexographic printing is a type of letterpress printing that primarily uses a rubber plate as the printing plate (relief plate). A fine-mesh engraving roller, called an anilox roller, is used to supply ink to this plate. The anilox roller receives ink from a cavity doctor blade and applies it to the printing plate. By using the anilox roller, it has the advantage of being able to transfer ink evenly onto the printing plate.

[0191] Specifically, ink is applied to the surface of an anilox roller, which has many partitions and openings surrounded by these partitions. A doctor blade is pressed against the surface of the anilox roller to scrape off the ink on the top surface of the partitions and fill the recesses that form the openings with ink. Next, a flexographic plate is pressed against the anilox roller, transferring the ink in the recesses to the protrusions (pattern areas) of the printing plate. Then, the printing plate is brought into contact with the substrate, transferring the ink in the pattern areas to the substrate, thereby obtaining a printed product.

[0192] Alternatively, rotary printing methods can be combined. For example, in the manufacturing method of rotary printed plastic film, water-based liquid printing ink is used for rotary printing on the surface of the rolled plastic film. After printing, processes such as lamination, slitting (cutting off unwanted portions of the width), and bag making (cutting and heat-sealing to form bags) can be performed. By rotary printing liquid ink onto the rolled plastic film, high-speed printing is possible, resulting in excellent productivity.

[0193] Rotary printing includes gravure rotary printing and flexographic rotary printing; either method is acceptable. As mentioned above, this application preferably uses flexographic printing to print water-based liquid printing inks. Therefore, flexographic rotary printing will be described in detail here. It should be noted that in this specification, rotary printing refers to both gravure and flexographic rotary printing, excluding inkjet printing and screen printing as other printing methods.

[0194] In flexographic rotary printing, ink is supplied directly from a container storing liquid printing ink or via an ink supply pump to an anilox roller with a textured surface. The ink supplied to the anilox roller is transferred to the printing plate by contact with the raised parts of the printing plate, and then finally transferred to the plastic film by contact between the printing plate and the plastic film, thereby forming a pattern and / or text.

[0195] When using water-based flexographic printing inks, the ink drying properties are slightly worse than those of solvent-based flexographic printing inks; therefore, the ink film thickness is preferably as thin as possible. Based on this, the amount of ink supplied to the anilox roller is preferably as small as possible. On the other hand, the print density tends to decrease as the film thickness decreases; therefore, it is sufficient to control the pigment concentration of the water-based flexographic printing ink used appropriately. Specifically, a suitable print density is obtained when the pigment concentration of the water-based flexographic printing ink is increased by 1 to 5% by weight compared to that of the solvent-based flexographic printing ink.

[0196] Rolled plastic film refers to a roll of plastic film aligned to a predetermined width, which is different from sheet paper pre-cut into individual sheets for rotary printing. The width of the film is appropriately selected based on the width of the rotary printing press and the width of the image (pattern) portion of the gravure plate.

[0197] It should be noted that when using multi-color rotary printing inks to overlap colors, there is no particular restriction on their printing order.

[0198] In surface printing, white ink is typically printed first, followed by colored inks, as needed. When multiple colored inks are used, they can be printed in the order of yellow, magenta, cyan, and black, but there are no particular restrictions. In surface printing, an coating agent is applied to the printing surface of the rotary print as needed, thereby improving its abrasion resistance and water resistance, among other properties.

[0199] When the substrate is white, such as paper substrate and plastic film mixed with white pigments, printing can also be carried out using only colored inks as needed.

[0200] In reverse printing, colored inks are typically printed first on the rolled plastic film, followed by white ink. When multiple colored inks are used, they can be printed in the order of black, cyan, magenta, and yellow, without particular restriction. It should be noted that in large-format printing presses, special colors can be used in addition to the basic colors mentioned above. That is, large-format printing presses have multiple printing units corresponding to 5 to 10 colors, with each printing unit containing ink of one color, allowing for overlapping printing of 5 to 10 colors at a time. Laminated materials can be obtained by applying anchoring agents and adhesives to the printing surface of the rotary print obtained using the above method, drying it as needed, and then bonding it to a film or similar material.

[0201] Furthermore, the printed layer of the printed material of the present invention has high scratch resistance and adhesion, and is therefore suitable for so-called surface-printed materials where the printed layer is the outermost layer. The method of use is not particularly limited. In a laminate consisting of multiple substrates containing the printed material having the above-mentioned printed layer, the printed layer can be located on the outermost layer of the laminate (so-called surface printing), or the printed layer can be located between the multiple substrates (so-called back printing). The water-based liquid printing ink of the present invention is applicable to inks of any composition. Alternatively, a structure in which a transparent overprinting varnish is provided on the printed layer is also possible. As an overprinting varnish composition, for example, a composition in which the water-based liquid printing ink forming the printed layer of the present invention does not contain a colorant is preferred.

[0202] (Layered structure)

[0203] The laminate of the present invention can be any laminate containing a printed material printed on at least one side of the polyolefin film used in the present invention using a plate-based printing method and printing ink used in the present invention. For example, a laminate formed by bonding the polyolefin film used in the present invention to other substrates using an adhesive or the like can be cited.

[0204] Other substrates include, for example, paper, synthetic paper, thermoplastic resin film, steel plate, aluminum foil, wood, woven fabric, knitted fabric, non-woven fabric, gypsum board, and wood-based panels. Among these, paper, synthetic paper, and thermoplastic resin film are preferred.

[0205] Examples of thermoplastic resin films include, for instance, general-purpose polyethylene films (LLDPE: low-density polyethylene film, MDPE: medium-density polyethylene film, HDPE: high-density polyethylene film), polypropylene films (CPP: non-stretched polypropylene film, OPP: biaxially stretched polypropylene film), polyethylene terephthalate (PET) films, polystyrene films, polyamide films, polyacrylonitrile films, polyvinyl alcohol films, ethylene-vinyl alcohol copolymer films, etc., other than the polyolefin films used in this invention. These films can undergo stretching treatment. As a stretching treatment method, typically, after the resin is melt-extruded into a sheet using a film-forming method such as extrusion, simultaneous biaxial stretching or sequential biaxial stretching is performed. Furthermore, in the case of sequential biaxial stretching, longitudinal stretching is typically performed first, followed by transverse stretching. Specifically, a method combining longitudinal stretching utilizing the speed difference between rollers with transverse stretching using a tenter frame is commonly used. Furthermore, films formed by depositing vapor-deposited layers of metals such as aluminum or stainless steel, or metal oxides such as silica or alumina, onto these laminated films can also be used.

[0206] Alternatively, membranes made of polycarbonate, polyethylene terephthalate, polymethyl methacrylate, polystyrene, polyester, polyolefin, epoxy resin, melamine resin, triacetyl cellulose resin, polyvinyl alcohol, ABS resin, norbornene resin, cyclic olefin resin, polyimide resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, ethylene-vinyl acetate copolymer, etc., which are widely used in industrial applications, can also be cited.

[0207] In addition, there is no particular limitation on the thickness of the substrate film, which can usually be in the range of 1 to 500 μm.

[0208] Furthermore, it can also be a laminate formed by bonding two or more of these substrates together with an adhesive. There are no particular limitations on the adhesive; general-purpose one-component adhesives, two-component adhesives, etc., can be used.

[0209] This is one example of the structure of the laminate of the present invention, but it is not limited thereto.

[0210] It should be noted that, here, the above-mentioned printed layer used in the present invention is referred to as "printed layer A", and the above-mentioned polyolefin film used in the present invention is referred to as "polyolefin film A".

[0211] (1) Printed layer A / Polyolefin film A / Adhesive layer 1 / Sealant film

[0212] (2) Printed layer A / Polyolefin film A / Adhesive layer 1 / Metal vapor deposited unstretched film

[0213] (3) Printed layer A / Polyolefin film A / Adhesive layer 1 / Metal vapor-deposited stretch film

[0214] (4) Printed layer A / Polyolefin film A / Transparent vapor-deposited stretch film / Adhesive layer 1 / Sealant film

[0215] (5) Printed layer A / Polyolefin film A / Adhesive layer 1 / Substrate film 2 / Adhesive layer 2 / Sealant film

[0216] (6) Printed layer A / Polyolefin film A / Adhesive layer 1 / Metal vapor-deposited stretch film / Adhesive layer 2 / Sealant film

[0217] (7) Printed layer A / Polyolefin film A / Adhesive layer 1 / Transparent vapor-deposited stretch film / Adhesive layer 2 / Sealant film

[0218] (8) Printed layer A / Polyolefin film A / Adhesive layer 1 / Metal layer / Adhesive layer 2 / Sealant film

[0219] (9) Printed layer A / Polyolefin film A / Adhesive layer 1 / Substrate film 2 / Adhesive layer 2 / Metal layer / Adhesive layer 3 / Sealing film

[0220] (10) Printed layer A / Polyolefin film A / Adhesive layer 1 / Metal layer / Adhesive layer 2 / Substrate film 2 / Adhesive layer 3 / Sealing film

[0221] (11) Printed layer A / Polyolefin film A / Adhesive layer 1 / Substrate film 2

[0222] (12) Printed layer A / Polyolefin film A

[0223] Examples of sealant films include CPP films and LLDPE films. For the aforementioned metal-deposited unstretched films, VM-CPP films, which have undergone aluminum or other metal deposition on CPP films, can be used. For metal-deposited stretched films, VM-OPP films, which have undergone aluminum or other metal deposition on OPP films, can be used. Examples of transparent vapor-deposited stretched films include films that have undergone silica or alumina deposition on OPP films, PET films, nylon films, etc. For the purpose of protecting the inorganic vapor-deposited layers of silica or alumina, films with coatings applied to the vapor-deposited layers can be used.

[0224] Examples of substrate films 2 include nylon films, PET films, and polyvinylidene fluoride films.

[0225] Examples of metal layers mentioned above include aluminum foil.

[0226] In these configurations, a general coating agent can also be applied to the printed layer A.

[0227] In addition, the thermoplastic resin film is preferably treated with corona discharge. It can be coated with silicon dioxide, aluminum oxide, etc., or it can be laminated with an oxygen barrier coating.

[0228] When using paper as the base material, it can be designed as moisture-proof paper. Examples of base paper include kraft paper, padding paper, coated paper, card stock, etc.

[0229] Furthermore, when using synthetic paper as the substrate, it can be configured as a moisture-proof synthetic paper. The structure of the synthetic paper is not particularly limited. Therefore, it can be a single-layer structure or a multi-layer structure. Examples of multi-layer structures include a two-layer structure with a substrate layer and a surface layer, a three-layer structure with a substrate layer and a surface layer on both sides, and a multi-layer structure with other resin film layers between the substrate layer and the surface layer. Additionally, each layer may contain inorganic or organic fillers, or it may not contain any. Furthermore, microporous synthetic paper with numerous tiny pores can also be used.

[0230] As a more specific example of a layered structure, examples include the following, but are not limited to:

[0231] The printed layer A / organic lubricant contains linear low-density polyethylene (LLDPE) film with a concentration of less than 1200 ppm by weight.

[0232] The medium-density polyethylene (MDPE) film containing organic lubricant in printed layer A at a concentration of less than 1200 ppm by weight.

[0233] The high-density polyethylene (HDPE) film containing organic lubricant in printed layer A at a concentration of less than 1200 ppm by weight.

[0234] The printed layer A / organic lubricant contains a non-stretched polypropylene (CPP) film with a concentration of less than 1200 ppm by weight.

[0235] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / General-purpose CPP

[0236] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / General-purpose VMCPP

[0237] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / VMPET / Adhesive layer 2 / General-purpose CPP

[0238] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / VMPET / Adhesive layer 2 / General purpose LLDPE

[0239] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / EVA / Adhesive layer 2 / General-purpose CPP

[0240] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / EVA / Adhesive layer 2 / General-purpose LLDPE

[0241] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / General-purpose LLDPE

[0242] Printed layer A / Biaxially oriented polypropylene film (OPP) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / AL / Adhesive layer 2 / General-purpose LLDPE

[0243] Printed layer A / Low-density polyethylene film (LLDPE) containing organic lubricant at a concentration of less than 1200 ppm by weight / Adhesive layer 1 / General-purpose LLDPE.

[0244] in,

[0245] CPP is a non-stretched polypropylene film.

[0246] OPP is a biaxially oriented polypropylene film.

[0247] LLDPE is a low-density polyethylene film.

[0248] MDPE is a medium-density polyethylene film.

[0249] HDPE is a high-density polyethylene film.

[0250] VMCPP is a film made by vapor deposition of metals such as aluminum onto a CPP film.

[0251] VMPET is a PET film that has undergone metal vapor deposition, such as aluminum.

[0252] EVA stands for ethylene vinyl alcohol.

[0253] AL stands for aluminum foil.

[0254] The printed material or laminate of the present invention is primarily used as a packaging material. For example, the laminate composed of the above-mentioned (12) printed layer A / polyolefin film A, which is the simplest structure of the above-mentioned printed layer A / organic lubricant containing linear low-density polyethylene film (LLDPE) with a concentration of less than 1200 ppm by mass, is expected to be both visually appealing and lightweight, and therefore can be used as a material for various outer packaging of industrial products such as food, hygiene products, cosmetics, and electronic components. In particular, it can be appropriately used as a material for outer packaging for hygiene purposes. In addition, when used as a multi-layer packaging material, its layer composition can be varied depending on the contents, the usage environment, and the usage method. Furthermore, the packaging body of the present invention can be appropriately provided with easy-opening and resealing mechanisms.

[0255] For example, packaging material can be obtained by heat-sealing the periphery of the laminate of the present invention by overlapping the sealing film faces side by side. As a bag-making method, examples include bending or overlapping the laminate of the present invention so that the inner surfaces (the sealing film surfaces) face each other, and then heat-sealing the periphery using methods such as side-sealing, two-side-sealing, three-side-sealing, four-side-sealing, envelope-fitting, palm-fitting, corrugated, flat-bottom, square-bottom, corner-supporting, and other heat-sealing methods. The packaging material of the present invention can take various forms depending on the contents, the usage environment, and the method of use. It can also be a self-standing packaging material (stand-up pouch). As a heat-sealing method, known methods such as strip sealing, rotary roller sealing, belt sealing, pulse sealing, high-frequency sealing, and ultrasonic sealing can be used.

[0256] The packaging material of the present invention is filled with contents through its opening, and the opening is then heat-sealed, thereby manufacturing an article using the packaging material of the present invention. Examples of the contents to be filled include, for example, food products such as: rice cakes, bean cakes, nuts, biscuits / cookies, wafers, marshmallows, pies, semi-baked cakes, candies, puffed foods, and other snacks; bread, crispy noodles, instant noodles, dried noodles, pasta, aseptically packaged rice, mixed porridge, rice porridge, packaged rice cakes, cereal products, and other staple foods; pickled vegetables, boiled beans, natto, miso, frozen tofu, tofu, enoki mushrooms, konjac, processed mountain vegetables, jams, peanut butter, salads, frozen vegetables, processed potato products, and other agricultural processed products; ham, bacon, sausages, processed chicken products, corned beef, etc. Processed livestock products; processed aquatic products such as fish, ham / sausage, surimi products, fish cakes, seaweed, salted seafood, dried bonito, salted fish, smoked salmon, and spicy cod roe; fruits and meats such as peaches, oranges, pineapples, apples, pears, and cherries; vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, and potatoes; frozen home-cooked dishes such as hamburgers, meatballs, fried seafood, dumplings, and croquettes; semi-finished home-cooked dishes and other condiments; dairy products such as butter, margarine, cheese, cream, instant cream powder, and infant formula; liquid seasonings, curry soft canned food, and pet food.

[0257] In addition, as a non-food product, it can also be used for various packaging materials such as diapers, pet pads for the bathroom, cigarettes, disposable hand warmers, IV bags, liquid detergents, liquid kitchen detergents, liquid bath detergents, liquid bath soaps, liquid shampoos, liquid conditioners, toners, lotions, vacuum insulation materials, and batteries.

[0258] Example

[0259] The present invention will be described in more detail below through embodiments. It should be noted that in the embodiments, "parts" means "parts by mass" and "%" means "% by mass".

[0260] The following water-based liquid printing inks are used as water-based liquid printing inks.

[0261] (Manufacturing method of liquid printing ink)

[0262] [Synthesis Example 1: Preparation of Acrylic Resin A]

[0263] A stirrer, thermometer, dropping funnel, and reflux pipe were installed in a reaction vessel, and 60.0 parts of n-propyl acetate were added. Under a nitrogen atmosphere, the mixture was stirred and heated to 90°C. Meanwhile, 30.0 parts of methyl acrylate, 45.0 parts of styrene, 25.0 parts of acrylic acid, and 1.4 parts of azobisisobutyronitrile (AIB) were dissolved in 40.0 parts of n-propyl acetate and added dropwise over 4 hours using a dropping funnel. After the addition was complete, the reaction was allowed to continue for 2 hours. After the reaction was complete, the mixture was cooled, and 18.0 parts of 30% ammonia water were added to the obtained acrylic resin solution for neutralization. Ion-exchanged water was then added, and solvent replacement was performed while heating to obtain an aqueous solution of acrylic resin A with 50% solids. The acid value was 195 mg KOH / g, the Tg was 74°C, and the weight-average molecular weight was 11,800.

[0264] [Synthesis Example 2: Preparation of Acrylic Resin B]

[0265] A stirrer, thermometer, dropping funnel, and reflux pipe were installed in a reaction vessel, and 60.0 parts of n-propyl acetate were added. Under a nitrogen atmosphere, the mixture was stirred and heated to 90°C. Meanwhile, 32.0 parts of methyl acrylate, 8.0 parts of styrene, 60.0 parts of acrylic acid, and 1.6 parts of azobisisobutyronitrile (AIB) were dissolved in 40.0 parts of n-propyl acetate and added dropwise over 4 hours using a dropping funnel. After the addition was complete, the reaction was allowed to continue for 2 hours. After the reaction was complete, the mixture was cooled, and 43.2 parts of 30% ammonia water were added to the obtained acrylic resin solution for neutralization. Ion-exchanged water was then added, and solvent replacement was performed while heating to obtain an aqueous solution of acrylic resin B with 50% solids. The acid value was 467 mg KOH / g, the Tg was 72°C, and the weight-average molecular weight was 11,800.

[0266] [Synthetic Example 3: Preparation of Core-Shell Acrylic Emulsion (A1)]

[0267] A reaction vessel containing 121.2 parts of an aqueous solution of acrylic resin A prepared in Synthesis Example 1 was equipped with a stirrer, thermometer, dropping funnel, and reflux tube, and 195.5 parts of deionized water was added. Under a nitrogen atmosphere, the mixture was stirred and heated to 75°C. Then, using a dropping funnel, 30.0 parts of methyl methacrylate, 10.0 parts of ethyl acrylate, 60 parts of 2-ethylhexyl acrylate, and 3.3 parts of 30% ammonium persulfate were added dropwise over 4 hours. After the addition was complete, the reaction was allowed to proceed for another 2 hours to obtain a core-shell acrylic emulsion (A1) aqueous solution with a solid content of 40%. The acid value was 98 mg KOH / g, the Tg was 20°C, and the weight-average molecular weight was 1,400,000.

[0268] [Synthetic Example 4: Preparation of Core-Shell Acrylic Emulsion (B1)]

[0269] A reaction vessel containing 121.2 parts of an aqueous solution of acrylic resin B prepared in Synthesis Example 2 was equipped with a stirrer, thermometer, dropping funnel, and reflux tube, and 195.5 parts of deionized water was added. Under a nitrogen atmosphere, the mixture was stirred and heated to 75°C. Then, using a dropping funnel, 30.0 parts of methyl methacrylate, 10.0 parts of ethyl acrylate, 60 parts of 2-ethylhexyl acrylate, and 3.3 parts of 30% ammonium persulfate were added dropwise over 4 hours. After the addition was complete, the reaction was allowed to proceed for another 2 hours to obtain a core-shell acrylic emulsion (B1) aqueous solution with a solid content of 40%. The acid value was 234 mg KOH / g, the Tg was 20°C, and the weight-average molecular weight was 1,400,000.

[0270] [Preparation Example 1: Preparation of Blue Pigment Dispersion]

[0271] A mixture of 45 parts of 15:3 pigment (manufactured by Sunchemical), 19 parts of alkali-soluble pigment dispersion water-soluble resin (ammonia neutralized, 30% solids), 2 parts of pigment dispersant, 2 parts of propylene glycol, and 32 parts of water was stirred and mixed, and then kneaded using a bead mill to produce a blue pigment dispersion.

[0272] [Preparation Example 2: Manufacturing of Blue Ink 1]

[0273] 28 parts of a core-shell acrylic emulsion (A1) with 40% solids prepared in Synthesis Example 3, 50 parts of a blue pigment dispersion prepared in Preparation Example 1, 9.5 parts of a styrene-acrylic emulsion with 35% solids, 2.3 parts of polyethylene wax, 0.9 parts of an alkyne-based surface conditioner, 0.1 parts of an antifoaming agent, and 9.2 parts of water were mixed to prepare acrylic blue ink 1. The viscosity of the obtained acrylic blue ink (ink 1) was confirmed to be 20 seconds (25°C) using a Zein cup #4 (manufactured by Lihe Co., Ltd.).

[0274] [Preparation Example 3: Manufacturing of Blue Ink 2]

[0275] Instead of the core-shell acrylic emulsion (A1) of Preparation Example 2, 28 parts of the 40% solids core-shell acrylic emulsion (B1) prepared in Synthesis Example 4 were used. Otherwise, acrylic blue ink 3 was prepared using the same formulation and sequence as in Preparation Example 2. The viscosity of the obtained acrylic blue ink (ink 2) was confirmed to be 19 seconds (25°C) using a Zein cup #4 (manufactured by Lihe Co., Ltd.).

[0276] It should be noted that in the above-mentioned manufacturing method of liquid printing ink, the weight-average molecular weight, acid value, and glass transition temperature (Tg) are determined by the following methods.

[0277] (Method for determining weight-average molecular weight)

[0278] The determination of weight-average molecular weight (converted to polystyrene) using GPC (gel permeation chromatography) in this invention was performed using an HLC8220 system manufactured by Tosoh Corporation under the following conditions.

[0279] Separation column: 4 TSKgelGMH columns manufactured by Tosoh Co., Ltd. HR -N. Column temperature: 40°C. Flow medium: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd. Flow rate: 1.0 ml / min. Sample concentration: 1.0% by mass. Sample injection volume: 100 μL. Detector: Differential refractometer.

[0280] (Acid value determination method)

[0281] The acid value of acrylic resin indicates the number of milligrams of potassium hydroxide required to neutralize the acidic components contained in 1g of resin. For each dried water-soluble resin, it is calculated by potentiometric titration using a potassium hydroxide / ethanol solution according to JIS K2501.

[0282] (Method for calculating glass transition temperature (Tg))

[0283] The glass transition temperature (Tg) refers to the calculated glass transition temperature, which is the value obtained by the following method.

[0284] (Equation 1) 1 / Tg(K)=(W1 / T1)+(W2 / T2)+···(Wn / Tn)

[0285] (Equation 2) Tg(℃)=Tg(K)-273

[0286] In Equation 1, W1, W2, ..., Wn represent the mass percentage of each monomer relative to the total mass of monomers used in the manufacture of the polymer, and T1, T2, ..., Tn represent the glass transition temperature (K) of the homopolymer of each monomer. It should be noted that the values ​​of T1, T2, ..., Tn are those described in the Polymer Handbook (4th Edition, edited by J. Brandrup, E. Himmergut, and E.A. Grulke).

[0287] Furthermore, the glass transition temperatures of the homopolymers of each monomer, which are not listed in the aforementioned polymer handbook, were determined using a differential scanning calorimeter "DSC Q-100" (manufactured by TA Instruments) according to the method in JIS K 7121. Specifically, for polymers in which the solvent was completely removed by vacuum aspiration, the heat change was measured in the range of -100°C to +200°C at a heating rate of 20°C / min. The point where the straight line extending from each baseline at equal distances along the vertical axis intersects the curve of the step-like change in glass transition temperature was defined as the glass transition temperature.

[0288] (Preparation of organic solvent-based inks)

[0289] A 30% solution was prepared by stirring and dissolving solid acrylic resin (Dianal BR-90 manufactured by Mitsubishi Chemical Co., Ltd.) using n-propyl acetate (NPAC), and this solution was designated as acrylic resin solution Ac.

[0290] Using a Dyno-mill (manufactured by Willy A Bachofen), 40 parts of the above-mentioned acrylic resin solution Ac, 15 parts of phthalocyanine blue pigment (DIC Co., Ltd. FASTGEN Blue LA5380), 2 parts of polyethylene wax, 8 parts of n-propyl acetate, and 35 parts of n-propanol (NPA) were mixed to produce a solvent-based printing ink (ink 3).

[0291] (Example 1)

[0292] In layer (A), linear low-density polyethylene (MFR: 3.5 g / 10 min (230 °C, 21.18 N), melting point: 123 °C, density: 0.935 g / cm³) was used. 3 Hereinafter, 90 parts of LLDPE1 are used as the polyolefin (a1), and ethylene-(meth)acrylate-maleic anhydride copolymer (density: 1.00 g / cm³) is used. 3 10 parts of a copolymer content of 15% (hereinafter referred to as "a2-1") were used as an acid-modified polyolefin resin (a2) that had been acid-modified by an unsaturated carboxylic acid component.

[0293] Layers (B1) and (B2) use 100 parts by weight of LLDPE1.

[0294] The layers were fed into three extruders and co-extruded with an average thickness of 2:6:2 for layers (A), (B1), and (B2) to form a three-layer film with a thickness of 40 μm. Then, the surface of layer (A) of the obtained three-layer film was subjected to corona discharge treatment with a surface energy of 36 mN / m to obtain a laminated film.

[0295] On the prepared laminated film, using a Flexoproof 100 test printing press (manufactured by RK Print Cort Instruments, Inc., Anilox 500 lines / inch), with an anilox roller and resin plate, the acrylic blue ink 1 obtained in the preparation example was printed at a speed of 50 m / min to produce a full-page pattern of 240 mm in length and 80 mm in width, thus obtaining the printed material.

[0296] (Example 2)

[0297] In layer (A) of Example 1, 80 parts of LLDPE and 20 parts of a2-1 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0298] (Example 3)

[0299] In layer (A) of Example 1, 70 parts of LLDPE and 30 parts of a2-1 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0300] (Example 4)

[0301] In layer (A) of Example 1, 60 parts of LLDPE and 40 parts of a2-1 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0302] (Example 5)

[0303] In layer (A) of Example 1, instead of ethylene-(meth)acrylate-maleic anhydride copolymer (a2-1), ethylene-(meth)acrylate copolymer [density: 0.940 g / cm³] was used. 3 The acid modification rate was 12%; hereinafter referred to as "a2-2"]. Otherwise, the printed matter was obtained by operating in the same manner as in Example 1.

[0304] (Example 6)

[0305] In layer (A) of Example 1, 80 parts of LLDPE and 20 parts of a2-2 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0306] (Example 7)

[0307] In layer (A) of Example 1, 70 parts of LLDPE and 30 parts of a2-2 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0308] (Example 8)

[0309] In layer (A) of Example 1, 60 parts of LLDPE and 40 parts of a2-2 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0310] (Example 9)

[0311] In Example 3, the acrylic blue ink 2 obtained in the preparation example was used to make the printed matter. Otherwise, the printed matter was obtained by operating in the same manner as in Example 3.

[0312] (Example 10)

[0313] In Example 7, the acrylic blue ink 2 obtained in the preparation example was used to make the printed matter. Otherwise, the printed matter was obtained by operating in the same manner as in Example 7.

[0314] (Comparative Example 1)

[0315] In layer (A) of Example 1, the LLDPE is set to 100 parts, and otherwise the print is obtained by operating in the same manner as in Example 1.

[0316] (Comparative Example 2)

[0317] In layer (A) of Example 4, instead of ethylene-(meth)acrylate-maleic anhydride copolymer (a2-1), ethylene-(meth)acrylate copolymer [density: 0.940 g / cm³] was used. 3 The content of MA is 18%; hereinafter referred to as "a3"]. Otherwise, the printed matter is obtained by operating in the same manner as in Example 4.

[0318] (Comparative Example 3)

[0319] In layer (A) of Example 1, 50 parts of LLDPE and 50 parts of a2-1 were used, and the print was obtained otherwise in the same manner as in Example 1.

[0320] (Comparative Example 4)

[0321] In layer (A) of Example 5, 50 parts of LLDPE and 50 parts of a2-2 were used, and the print was obtained otherwise in the same manner as in Example 5.

[0322] (Refer to Example 5)

[0323] In Example 3, the printed matter was made using the organic solvent-based ink 3 obtained in the preparation example. Otherwise, the printed matter was obtained by operating in the same manner as in Example 3.

[0324] (Refer to Example 6)

[0325] In Example 7, the printed matter was made using the organic solvent-based ink 3 obtained in the preparation example. Otherwise, the printed matter was obtained by operating in the same manner as in Example 7.

[0326] [Evaluation Items]

[0327] The following evaluation was conducted using the produced films and printed materials.

[0328] <Membrane Haze>

[0329] The haze (in %) of the obtained film was measured using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K7105. Transparency was evaluated according to the following criteria.

[0330] 5:0 or higher and less than 5%

[0331] 4: 5% or more but less than 10%

[0332] 3: 10% or more but less than 15%

[0333] 2: 15% or more but less than 20%

[0334] 1: More than 20%

[0335] <Film gloss>

[0336] Using the obtained film, the gloss (in %) of one film was measured using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K7105.

[0337] 5: More than 115%

[0338] 4: 100% or more but less than 115%

[0339] 3: 85% or more but less than 100%

[0340] 2: 70% or more but less than 85%

[0341] 1: Less than 70%

[0342] <Membrane Rigidity>

[0343] For the obtained membrane, the 1% tangential modulus (in MPa) at 23°C was determined using a Tensilon tensile testing machine (manufactured by A&D Corporation) based on ASTM D-882. The determination was performed in the extrusion direction (hereinafter referred to as "MD") and the membrane width direction (hereinafter referred to as "CD") during membrane manufacturing.

[0344] <Membrane Impact Resistance>

[0345] The obtained membrane was left to stand in a constant temperature chamber set to 0°C for 4 hours. Then, the impact strength was determined by membrane impact method using a Tester Industrial BU-302 membrane impact testing machine with a 1.5-inch impact head mounted on the top of the pendulum.

[0346] <Ink Transfer Properties>

[0347] Flexographic verification printing was performed at a printing speed of 50 m / min, and the degree of ink transfer to the evaluation film was visually assessed.

[0348] 5: The entire printed surface is transferred, and the depression is completely invisible.

[0349] 4: The entire printed surface was transferred, but some uneven transfer was observed.

[0350] 3: Uneven transfer is visible on some parts of the printed surface, but it is within the acceptable range.

[0351] 2: Uneven transfer is visible across the entire printed surface.

[0352] 1. The entire printed surface has ink depressions that have not been transferred.

[0353] <Seamless fit>

[0354] The resulting printed material is then pressed firmly against an 18mm wide NICHIBAN Cellotape (registered trademark), and the degree of ink peeling is visually assessed. It should be noted that the adhesion is evaluated both immediately after printing and 24 hours later.

[0355] 5: No coating peeling is visible at all.

[0356] 4: Very little coating peeling can be detected.

[0357] 3: Coating peeling can be slightly observed, but it is within the practical range.

[0358] 2: Extensive coating peeling was observed.

[0359] 1: Peeling of the coating is clearly visible.

[0360] <Abrasion Resistance>

[0361] The printed material was scratched with a fingernail (10 times), and the degree of ink peeling was visually assessed. It should be noted that scratch resistance was evaluated both immediately after printing and 24 hours later.

[0362] 5: No coating peeling is visible at all.

[0363] 4: Very little coating peeling can be detected.

[0364] 3: Coating peeling can be slightly observed, but it is within the practical range.

[0365] 2: Extensive coating peeling was observed.

[0366] 1: Peeling of the coating is clearly visible.

[0367] <Anti-adhesion>

[0368] Cut the film into 4cm x 4cm pieces and overlap them, applying a 5kgf / cm coating with the printed and non-printed surfaces in contact. 2 The load was applied, and after being placed in an environment of 40°C for 12 hours, the film was peeled off. The transfer of ink to the non-printed surface (staining) was visually determined based on the area ratio (%) of the contaminated part (ink / film anti-adhesion).

[0369] In addition, the film was cut into 4cm×4cm pieces and overlapped with the printed surfaces in contact with each other, and the anti-blocking property was judged in the same way as the ink / film anti-blocking property mentioned above (ink / ink anti-blocking property).

[0370] 5; No transfer to the printed surface is visible at all.

[0371] 4: Less than 5%, but transfer is observed.

[0372] 3: Observe a transfer rate of more than 5% but less than 20%.

[0373] 2: Observe a transfer rate of 20% or more but less than 50%.

[0374] 1: Observing a transfer rate of over 50%

[0375] The results are shown in the table below.

[0376] [Table 1]

[0377]

[0378] [Table 2]

[0379]

[0380] [Table 3]

[0381]

[0382] Based on the above results, for the film of the embodiment in which the printing surface layer uses an acid-modified polyolefin resin (a2) containing 10% to 40% by mass of an acid-modified unsaturated carboxylic acid component, excellent results were obtained in ink transfer, adhesion, scratch resistance, and anti-blocking properties, achieving results comparable to those of the reference example using organic solvent-based inks. On the other hand, for Comparative Examples 3 and 4, where the content of acid-modified polyolefin resin (a2) containing an acid-modified unsaturated carboxylic acid component is greater than 40% by mass, the film haze and gloss decreased, resulting in a decrease in the gloss of the printed material, and a tendency for a decrease in anti-blocking properties was observed.

Claims

1. A packaging material using a printed material, said printed material having multiple layers of film and a printed layer, The multilayer film has at least one layer (A), wherein the layer (A) is mainly composed of a non-cyclic polyolefin (a1) and also contains 10% by mass and 40% by mass of an acid-modified polyolefin resin (a2) that has been acid-modified by an unsaturated carboxylic acid component. The printed layer is formed by printing water-based liquid printing ink onto layer (A).

2. The packaging material according to claim 1, wherein the non-cyclic polyolefin (a1) contains a polyethylene resin (a1-1).

3. The packaging material according to claim 1 or 2, wherein the printed layer has an outer covering layer.

4. The packaging material according to claim 1 or 2, wherein the multilayer film further has a layer (B) containing a polyolefin resin (b) on the side of the layer (A) opposite to the side where the printed layer is disposed.

5. The packaging material according to claim 4, wherein the thickness ratio of layer (A) is 5% to 50% relative to the total thickness of layer (A) and layer (B).

6. The packaging material according to claim 1 or 2, wherein the layer (A) contains 50% by mass or more of the non-cyclic polyolefin (a1) relative to the total amount of the resin composition forming the layer (A).

7. The packaging material according to claim 1 or 2, wherein it is a surface-printed material.

8. The packaging material according to claim 1 or 2, wherein the acid modification rate of the acid-modified polyolefin resin (a2) modified with unsaturated carboxylic acid is 0.5 to 40%, and wherein the layer (A) contains 18% by mass and 32% by mass of the acid-modified polyolefin resin (a2) modified with unsaturated carboxylic acid relative to the total amount of the resin composition forming the layer (A).

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