Film laminate

Abstract

As shown in fig. 1, a film laminate 100 of the present invention has a transparent resin layer 110, an ultraviolet curable adhesive layer 120, an ultraviolet curable print layer 130, and a substrate resin layer 140, in this order. Both the ultraviolet curable adhesive layer 120 and the ultraviolet curable print layer 130 have a cured product of an ultraviolet curable resin. At least one layer among the ultraviolet curable adhesive layer 120 and the ultraviolet curable print layer 130 has a cured product of an isocyanate and an ultraviolet curable resin.

Description

Film laminate

[0001] The present invention relates to a film laminate.

[0002] Ultraviolet-curable ink is an ink that cures by undergoing a photochemical reaction with the energy of ultraviolet light. It has characteristics such as quick drying, high film physical properties, and solvent-free, and is adopted in various printing fields.

[0003] Film laminates printed with ultraviolet-curable ink (UV ink) have various known structures. In Patent Document 1, a laminate for a tube includes a laminated surface layer, an adhesive layer, a UV ink layer, and a base material laminate. The surface layer contains polyolefin, the adhesive layer is formed of a two-component adhesive of a polyol having an ester moiety and a polyisocyanate, the surface of the base material laminate that contacts the UV ink layer is formed of polyolefin, and the UV ink layer is disposed at a location corresponding to the seal portion on the surface of the base material laminate. According to the invention of Patent Document 1, the laminate strength is improved between the surface layer and the UV ink layer, so that cohesive delamination can be prevented and laminate lifting of the surface layer due to stress can be prevented.

[0004] Further, in Patent Document 2, in a method for manufacturing a tube container web, a printing layer is formed on a single-layer sheet made of a polyethylene layer or a multi-layer sheet whose surface is a polyethylene layer using ultraviolet-curable ink, an ultraviolet-curable adhesive is applied on the printing layer to form an ultraviolet-curable adhesive layer, and then a polyethylene film is adhered to the sheet through the ultraviolet-curable adhesive layer to form a protective layer for the printing layer. A method for manufacturing a tube container web is disclosed. According to the invention of Patent Document 2, a tube container web can be manufactured with a simple manufacturing method and a small number of manufacturing steps on the printing layer of the web without requiring large-scale manufacturing equipment.

[0005] International Publication No. 2014 / 178403, Japanese Unexamined Patent Application Publication No. 2015-136918

[0006] In Patent Document 1, when a transparent resin layer is laminated on a UV-curable printed layer formed with UV-curable ink, the UV-curable printed layer and the transparent resin layer are bonded together with a two-component adhesive. However, because an aging time is required to cure the two-component adhesive, productivity is reduced.

[0007] On the other hand, Patent Document 2 describes a method in which an ultraviolet-curable printed layer and a transparent resin layer are bonded together with an ultraviolet-curable adhesive, thus enabling lamination without the need for aging time. However, ultraviolet-curable adhesives may have inferior adhesive strength compared to two-component adhesives.

[0008] Therefore, the present invention aims to provide a film laminate having high lamination strength and high productivity.

[0009] The present inventors, after diligent study, have found that the above problems can be solved by the following means, and have completed the present invention. <Aspect 1> A film laminate having a transparent resin layer, an ultraviolet-curable adhesive layer, an ultraviolet-curable printing layer, and a base resin layer in this order, wherein both the adhesive layer and the printing layer have a cured product of an ultraviolet-curable resin, and at least one of the adhesive layer and the printing layer has an isocyanate and a cured product of an ultraviolet-curable resin. <Aspect 2> The laminate according to Aspect 1, wherein the laminate strength of the film laminate is 3.0 N / 15 mm or more. <Aspect 3> The laminate according to Aspect 1 or 2, wherein the transparent resin layer is an outer sealant layer. <Aspect 4> The laminate according to any one of Aspects 1 to 3, wherein the ultraviolet-curable resin is an acrylic resin. <Aspect 5> The laminate according to any one of Aspects 1 to 4, wherein the ultraviolet-curable printing layer is a flexographic ink layer. <Aspect 6> The laminate according to any one of aspects 1 to 5, wherein the isocyanate is a polyisocyanate. <Aspect 7> The laminate according to any one of aspects 1 to 6, which is a laminate for a laminate tube container. <Aspect 8> A laminate tube container having the laminate according to aspect 7.

[0010] According to the present invention, it is possible to provide a film laminate having high lamination strength and high productivity.

[0011] Figure 1 is a side cross-sectional view of one embodiment of the film laminate of the present invention.

[0012] 《Film Laminate》 The film laminate of the present invention comprises a transparent resin layer, an ultraviolet-curable adhesive layer, an ultraviolet-curable printing layer, and a base resin layer in this order, wherein both the adhesive layer and the printing layer have a cured product of an ultraviolet-curable resin, and at least one of the adhesive layer and the printing layer has an isocyanate and a cured product of an ultraviolet-curable resin.

[0013] According to the present invention, it is possible to provide a film laminate having high lamination strength and high productivity.

[0014] The inventors have found that when a transparent resin layer and an ultraviolet-curable printed layer are bonded together using an ultraviolet-curable adhesive layer, the adhesive strength between the ultraviolet-curable printed layer and the ultraviolet-curable adhesive layer is low. While not limited to theory, one possible reason for this is that the ultraviolet-curable adhesive layer is laminated after the ultraviolet-curable printed layer has been cured by ultraviolet irradiation, resulting in a state similar to a so-called cold joint, and these layers are not sufficiently bonded together.

[0015] In contrast, the present inventors have found that by having at least one of the UV-curable adhesive layer and the UV-curable printing layer contain cured products of isocyanate and UV-curable resin, the adhesive strength of these layers is increased, and the lamination strength of the film laminate is increased. Although not limited to theory, this is thought to be due to the adhesion occurring when the isocyanate reacts with the hydroxyl groups of the resin constituting the UV-curable adhesive layer and / or UV-curable printing layer and hardens.

[0016] Specifically, for example, as shown in Figure 1, the film laminate 100 has a transparent resin layer 110, an ultraviolet-curable adhesive layer 120, an ultraviolet-curable printing layer 130, and a base resin layer 140 in this order. Of the isocyanate and the cured product of the ultraviolet-curable resin present in the ultraviolet-curable printing layer 130, the isocyanate is thought to form a urethane bond by bonding with the hydroxyl groups present in the resin constituting the ultraviolet-curable adhesive layer 120, thereby increasing the adhesive strength between the ultraviolet-curable adhesive layer 120 and the ultraviolet-curable printing layer 130. Note that the isocyanate and the cured product of the ultraviolet-curable resin may be present only in the ultraviolet-curable adhesive layer 120, or both the ultraviolet-curable adhesive layer 120 and the ultraviolet-curable printing layer 130 may be present.

[0017] The following describes each component of the present invention.

[0018] The film laminate of the present invention comprises a transparent resin layer, an ultraviolet-curable adhesive layer, an ultraviolet-curable printing layer, and a base resin layer in this order.

[0019] The lamination strength of the film laminate is preferably 3.0 N / 15 mm or more, 4.0 N / 15 mm or more, 5.0 N / 15 mm or more, 7.0 N / 15 mm or more, or 10.0 N / 15 mm or more. Alternatively, the lamination strength may be 30.0 N / 15 mm or less, 25.0 N / 15 mm or less, 20.0 N / 15 mm or less, or 18.0 N / 15 mm or less.

[0020] In this specification, "laminate strength" refers to the force required when a test piece is cut from the prepared film laminate to a width of 15 mm and a length of 100 mm, a certain amount of the transparent resin layer is peeled off, and the peeled transparent resin layer and the base resin layer are pinched together using a Strograph (manufactured by Toyo Seiki Seisakusho, VGF) and peeled off at a 90-degree angle in the longitudinal direction.

[0021] <Transparent Resin Layer> The transparent resin layer can be any resin layer, such as a resin film layer, that is transparent to ultraviolet light to the extent that ultraviolet light can be irradiated through it to the ultraviolet-curable adhesive layer, and its function is not particularly limited. The transparent resin layer may be a single layer, or a laminate in which multiple layers are stacked, and may contain multiple layers of the same type. For example, for the purpose of forming a laminate tube, the transparent resin layer may be an outer sealant layer.

[0022] (Outer sealant layer) The outer sealant layer may be made of polyethylene resin.

[0023] In this specification, polyethylene resins are resins containing more than 50 mol%, 60 mol%, 70 mol%, or 80 mol% of repeating ethylene groups in the main chain of the polymer, and are selected from the group consisting of, for example, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), and derivatives thereof, as well as mixtures thereof.

[0024] The thickness of the outer sealant layer is not particularly limited, but from the viewpoint of ensuring strength, it is preferable that it is, for example, 50 μm or more, 60 μm or more, 70 μm or more, 80 μm or more, 85 μm or more, 90 μm or more, or 95 μm or more. Furthermore, from the viewpoint of improving the handling of the film laminate, it is preferable that it is 200 μm or less, 190 μm or less, 180 μm or less, 170 μm or less, 160 μm or less, 150 μm or less, 140 μm or less, 130 μm or less, 125 μm or less, 120 μm or less, 115 μm or less, 110 μm or less, or 105 μm or less.

[0025] <UV-curable adhesive layer> The UV-curable adhesive layer is the layer that adheres the transparent resin layer to the UV-curable printing layer.

[0026] The UV-curable adhesive layer has a cured product of UV-curable resin.

[0027] In this specification, "cured product of UV-curable resin" means a cured product produced when UV-curable resin is irradiated with ultraviolet light and undergoes a photochemical reaction.

[0028] In this specification, "ultraviolet-curable resin" means a resin that has the property of hardening when irradiated with ultraviolet light, that is, a resin before hardening.

[0029] The UV-curing resin may be an acrylic resin. The acrylic resin is not particularly limited, but for example, polyurethane acrylate, epoxy acrylate, acrylic resin acrylate, and polyester acrylate can be used.

[0030] Examples of polyurethane acrylates that can be used include aromatic polyurethane acrylates and aliphatic polyurethane acrylates.

[0031] In this specification, "aromatic polyurethane acrylate" refers to polyurethane acrylate having a benzene ring, and "aliphatic polyurethane acrylate" refers to polyurethane acrylate not having a benzene ring.

[0032] At least one of the UV-curable adhesive layer and the UV-curable printing layer has a cured product of isocyanate and UV-curable resin.

[0033] In this specification, "cured product of isocyanate and UV-curable resin" refers to the cured product produced by irradiating a mixture of isocyanate and UV-curable resin with ultraviolet light, causing a photochemical reaction of the UV-curable resin. Here, the isocyanate is thought to form urethane bonds with the hydroxyl groups of the resins constituting the UV-curable adhesive layer and the UV-curable printing layer. That is, the isocyanate crosslinks the resins with urethane bonds. Then, the intermolecular forces in the urethane bonds (e.g., hydrogen bonds) improve the laminate strength and the strength of the resin itself.

[0034] In this specification, "isocyanate" means a compound having at least one isocyanate group.

[0035] The isocyanate may be a polyisocyanate. In this specification, "polyisocyanate" means a compound having at least two isocyanate groups. The polyisocyanate may be, for example, an aliphatic polyisocyanate or an aromatic polyisocyanate.

[0036] Examples of aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, and 2,6-diisocyanatohexanoate. Examples include aliphatic diisocyanates such as 2-isocyanatoethyl 2,6-diisocyanatohexanoate, 1,6-diisocyanato-3-isocyanatomethylhexane, 1,4,8-triisocyanatooctane, 1,6,11-triisocyanatoundecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, and 2,5,7-trimethyl-1,8-diisocyanato-5-isocyanatomethyloctane.

[0037] Examples of aromatic polyisocyanates include aromatic diisocyanates such as m-phenylenediisocyanate, p-phenylenediisocyanate, 4,4'-diphenyldiisocyanate, 1,5-naphthalenediisocyanate, 2,4-tolylenediisocyanate or 2,6-tolylenediisocyanate, 4,4'-toluidinediisocyanate, and 4,4'-diphenyletherdiisocyanate; aromatic triisocyanates such as triphenylmethane-4,4',4''-triisocyanate, 1,3,5-triisocyanatobenzene, and 2,4,6-triisocyanatotoluene; and aromatic tetraisocyanates such as 4,4'-diphenylmethane-2,2',5,5'-tetraisocyanate.

[0038] The isocyanate may be contained by adding an additive containing isocyanate to the ultraviolet curable adhesive layer and / or the ultraviolet curable printing layer.

[0039] The content of the additive containing isocyanate is not particularly limited and may be any amount that can enhance the adhesion between the ultraviolet curable adhesive layer and the ultraviolet curable printing layer. The content of the additive containing isocyanate is, for example, 1% by mass or more, 2% by mass or more, 3% by mass or more, 4% by mass or more, 5% by mass or more, 6% by mass or more, 7% by mass or more, or 8% by mass or more with respect to the mass of the layer containing at least one of the ultraviolet curable adhesive layer and the ultraviolet curable printing layer, and may also be 30% by mass or less, 25% by mass or less, or 20% by mass or less.

[0040] The isocyanate content of the additive containing isocyanate is not particularly limited and may be, for example, 1% by mass or more, 10% by mass or more, 30% by mass or more, or 50% by mass or more with respect to the mass of the additive containing isocyanate, and may also be 100% by mass or less, 80% by mass or less, or 60% by mass or less.

[0041] The thickness of the ultraviolet curable adhesive layer is not particularly limited. For example, from the viewpoint of ensuring strength, it is preferably 0.5 μm or more, 1.0 μm or more, 1.5 μm or more, or 2.0 μm or more. Also, from the viewpoint of improving the handling property of the film laminate, the thickness of the ultraviolet curable adhesive layer is preferably 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, 15 μm or less, or 12 μm or less.

[0042] 〈Ultraviolet curable printing layer〉The ultraviolet curable printing layer is a layer for printing characters, pictures, symbols, etc. on the surface of the base resin layer. The ultraviolet curable printing layer may be laminated on the entire surface of the base resin layer or on a part of the base resin layer.

[0043] The ultraviolet curable printing layer has a cured product of an ultraviolet curable resin. Regarding the ultraviolet curable resin, the description regarding the above ultraviolet curable adhesive layer can be referred to. Also, the ultraviolet curable printing layer may have pigments, various additives, etc.

[0044] At least one of the ultraviolet-curable adhesive layer and the ultraviolet-curable printing layer has a cured product of an isocyanate and an ultraviolet-curable resin. For this cured product, the description regarding the above ultraviolet-curable adhesive layer can be referred to.

[0045] The ultraviolet-curable printing layer may be a layer formed of flexographic ink, that is, a flexographic ink layer. Flexographic ink has high printing reproducibility for substrates having various surface characteristics, for example, for polyolefin substrates.

[0046] The thickness of the ultraviolet-curable printing layer is not particularly limited. For example, it is preferably 0.5 μm or more, 1.0 μm or more, 1.5 μm or more, or 2.0 μm or more from the viewpoint of ensuring strength. Also, the thickness of the ultraviolet-curable printing layer is preferably 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, 15 μm or less, or 12 μm or less from the viewpoint of improving the handling property as a film laminate.

[0047] As the pigment, for example, titanium oxide, lead molybdate chromate, lead yellow, iron oxide, calcium carbonate, barium sulfate, aluminum powder, zinc sulfide, synthetic mica, natural mica, etc. can be used. By including the pigment, the design property can be improved.

[0048] 〈Base resin layer〉The base resin layer is an impermeable base material on which the ultraviolet-curable printing layer is laminated on its surface. The base resin layer has resin at least in part. The base resin layer may be a single layer, or may be a laminate in which a plurality of layers are laminated, and may include a plurality of layers of the same type.

[0049] The base resin layer may have, for example, a printing layer, a barrier layer, a reinforcing layer, and an inner sealant layer. These layers may be laminated by any lamination means.

[0050] (Printing layer) The printing layer is not particularly limited as long as it has a degree of impermeability that allows the ultraviolet-curable printing layer to be printed, and may be, for example, a resin layer.

[0051] As the printable layer, thermoplastic resins such as polyolefin resins, vinyl polymers, polyesters, and polyamides can be used individually or in combination of two or more types in a multilayer structure. Such thermoplastic resins can be used in the form of a film or an extruded resin. Furthermore, the film may be a stretched film or an unstretched film.

[0052] For example, polyethylene resins and polypropylene resins can be used as polyolefin resins. For polyethylene resins, please refer to the description of the outer sealant layer above.

[0053] In this specification, polypropylene resins are resins that contain more than 50 mol%, 60 mol%, 70 mol%, or 80 mol% of repeating propylene groups in the main chain of the polymer, and include, for example, polypropylene (PP) homopolymers, random polypropylene (random PP), blocked polypropylene (block PP), chlorinated polypropylene, acid-modified polypropylene, and derivatives thereof, as well as mixtures thereof.

[0054] Examples of vinyl polymers include polyvinyl chloride (PVC).

[0055] Examples of polyesters include polyethylene terephthalate (PET) and polybutylene terephthalate.

[0056] Examples of polyamides include nylons such as nylon (registered trademark) 6 and nylon MXD6.

[0057] (Barrier layer) As the barrier layer, for example, an inorganic vapor deposition layer, a metal foil layer, an organic coating layer, etc., can be used.

[0058] Examples of inorganic vapor-deposited layers include silica vapor-deposited films, aluminum vapor-deposited films, alumina vapor-deposited films, and silica-alumina vapor-deposited films.

[0059] As the metal foil layer, for example, single metal foils such as aluminum foil, copper foil, and titanium foil, or alloy foils such as aluminum alloy foil and stainless steel foil can be used.

[0060] For example, a vinylidene chloride coating layer or a polyvinylidene fluoride coating layer can be used as the organic coating layer.

[0061] When an inorganic vapor-deposited film or an organic coating layer is used as the barrier layer, the thickness of the barrier layer is preferably 100 nm or more, 200 nm or more, 300 nm or more, 500 nm or more, 700 nm or more, or 1 μm or more from the viewpoint of ensuring strength and barrier properties, and is preferably 5 μm or less, 4 μm or less, 3 μm or less, or 2 μm or less from the viewpoint of improving the handlingability of the film laminate.

[0062] When a metal foil layer is used as the barrier layer, the thickness of the barrier layer is preferably 3 μm or more, 5 μm or more, 7 μm or more, 10 μm or more, or 15 μm or more from the viewpoint of ensuring strength and barrier properties. Furthermore, a thickness of 100 μm or less, 80 μm or less, 60 μm or less, 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, or 35 μm or less is preferable from the viewpoint of improving the handlingability of the film laminate.

[0063] (Reinforcement layer) The reinforcement layer may be a layer made of stretched film.

[0064] The reinforcing layer may be a stretched film composed of, for example, a polyolefin resin or a polyamide resin. For polyolefin resins and polyamide resins, refer to the description of the printed layer above.

[0065] If the reinforcing layer is composed of a stretched film, the stretched film constituting the reinforcing layer may be a stretched film obtained, for example, by flat stretching, and may be a uniaxially stretched film or a biaxially stretched film. The biaxially stretched film may be a sequentially stretched biaxially stretched film or a simultaneously stretched biaxially stretched film, or a stretched film obtained by performing these stretching operations multiple times.

[0066] From the viewpoint of ensuring strength, the thickness of the reinforcing layer is preferably 5 μm or more, 7 μm or more, 10 μm or more, 12 μm or more, or 25 μm or more. Furthermore, from the viewpoint of not making the total thickness of the film laminate excessively large, the thickness of the reinforcing layer is preferably 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, 15 μm or less, or 12 μm or less.

[0067] (Inner sealant layer) The inner sealant layer may be composed of polyethylene resin. For polyethylene resins, refer to the description of the outer sealant layer above.

[0068] The thickness of the inner sealant layer is not particularly limited, but from the viewpoint of ensuring strength, it is preferable that it is, for example, 50 μm or more, 60 μm or more, 70 μm or more, 80 μm or more, 85 μm or more, 90 μm or more, or 95 μm or more. Furthermore, from the viewpoint of improving the handling of the film laminate, it is preferable that it is 200 μm or less, 190 μm or less, 180 μm or less, 170 μm or less, 160 μm or less, 150 μm or less, 140 μm or less, 130 μm or less, 125 μm or less, 120 μm or less, 115 μm or less, 110 μm or less, or 105 μm or less.

[0069] <Method for Manufacturing Film Laminates> The method for manufacturing film laminates is not particularly limited and may include, for example, a printing step of laminating an ultraviolet-curable printed layer onto a base resin layer, and may further include a lamination step of laminating an ultraviolet-curable adhesive layer and a transparent resin layer onto the ultraviolet-curable printed layer. For details on film laminates, refer to the above description of film laminates.

[0070] In the printing process, a UV-curable printing layer may be formed by printing on the printable surface of the substrate resin layer with an ink containing, for example, a UV-curable resin, and curing the UV-curable resin by irradiating it with ultraviolet light.

[0071] The ink and printing method containing the UV-curing resin are not particularly limited, and may be, for example, a flexographic ink, in which case the printing method may be flexographic printing. The ink may also contain isocyanate, in which case the ink may be made to contain isocyanate by adding an additive containing isocyanate.

[0072] The amount of ultraviolet radiation is, for example, 25 mJ / cm². ２ Above, 30mJ / cm ２ 35 mJ / cm ２ , or 40 mJ / cm ２ The above is preferable from the viewpoint of ensuring the strength of the UV-curable printed layer.

[0073] In the lamination process, after the printing process, an adhesive containing an ultraviolet-curable resin may be applied to the surface of the ultraviolet-curable printing layer, and a transparent resin layer may be further laminated on the adhesive. By irradiating the transparent resin layer with ultraviolet light from the surface side, the ultraviolet-curable resin may be cured to form an ultraviolet-curable adhesive layer and a transparent resin layer.

[0074] The adhesive containing the UV-curable resin may be a generally known UV-curable adhesive. If the UV-curable printing layer does not contain isocyanate, the adhesive will contain isocyanate. In this case, isocyanate may be added to the adhesive by adding an additive containing isocyanate.

[0075] The method of applying the adhesive is not particularly limited and may be, for example, flexographic printing. Flexographic printing allows this process to be carried out continuously after the printing process described above.

[0076] The amount of ultraviolet radiation is, for example, 25 mJ / cm². ２ Above, 30mJ / cm ２ 35 mJ / cm ２ , or 40 mJ / cm ２ The above is preferable from the viewpoint of ensuring the strength of the UV-curable adhesive layer.

[0077] 《Laminate for Laminate Tube Containers》 The film laminate of the present invention may also be a laminate for laminate tube containers.

[0078] According to the present invention, it is possible to provide a laminate for laminate tube containers that has high lamination strength and high productivity.

[0079] When the film laminate of the present invention is applied to a laminate for a laminate tube container, the transparent resin layer has an outer sealant layer, and the base resin layer has an inner sealant layer. The cylindrical body of the laminate tube container can be manufactured by heat-sealing a portion of the outer sealant layer and the inner sealant layer (side seam portion).

[0080] Laminated Tube Container The laminated tube container has a laminate for laminated tube containers according to the present invention.

[0081] According to the present invention, it is possible to provide a laminate tube container having high lamination strength and high productivity.

[0082] The laminate tube container of the present invention may have a head portion having a shoulder portion and a cap portion, and a tail seal portion located on the opposite side of the head portion.

[0083] Laminated tube containers can be filled with contents such as pharmaceuticals, cosmetics, and food. Examples of contents include toothpaste, moisturizing cream, and sunscreen.

[0084] Laminated tube containers can be manufactured by a method including, for example, the following steps: forming a side seam by forming a body portion by overlapping and heat-sealing the ends of a laminated tube while rolling it so that the base material, particularly the sealant layer of the base material, is on the inside; and attaching a head portion having a shoulder portion and a cap portion to the periphery of the opening of the body portion to obtain a laminated tube container.

[0085] The present invention will be specifically described by examples and comparative examples, but the present invention is not limited thereto.

[0086] 《Preparation of Film Laminate》 An acrylate ink (Toyo Ink, FDFL White MP) containing isocyanate additives (Toyo Ink, FDSS additives) as shown in Table 1 was applied to the surface of the base resin layer using Flexiproof (Matsuo Sangyo, Flexiproof 100) with an anilox roll to a film thickness of 0.5 to 3 μm and cured to form an ultraviolet-curable printing layer.

[0087] Next, an ultraviolet-curable resin (SCK-16D, manufactured by Daido Chemical Industries, or FDFL Medium MP, manufactured by Toyo Ink) containing an isocyanate additive (FDSS additive, manufactured by Toyo Ink) as shown in Table 1 was applied to the surface of the ultraviolet-curable printing layer using an anilox roll to a thickness of 0.5 to 3 μm. An LLDPE film (80 μm) was then laminated as a transparent resin layer, and the ultraviolet-curable resin was cured by irradiating it with ultraviolet light from the transparent resin layer side to produce the film laminates of Examples 1 to 8 and Comparative Examples 1 to 2.

[0088] 《Evaluation of Lamination Strength of Film Laminates》 The film laminates of Examples 1-8 and Comparative Examples 1-2 were cut into 15 mm wide x 100 mm long test pieces. A certain amount of the transparent resin layer was peeled off, and the force required to pinch the peeled transparent resin layer and the base resin layer and peel them 90 degrees in the length direction was measured and evaluated using a Strograph (VGF, manufactured by Toyo Seiki Seisakusho). The evaluation results are shown in Table 1.

[0089]

[0090] From Examples 1 to 8 and Comparative Examples 1 to 2 in Table 1, it can be understood that by including a predetermined amount of isocyanate in the UV-curable adhesive layer and / or UV-curable printing layer, the adhesive strength between the UV-curable adhesive layer and the UV-curable printing layer can be increased, thereby increasing the lamination strength of the film laminate.

[0091] 100 Film laminate 110 Transparent resin layer 120 UV-curable adhesive layer 130 UV-curable printing layer 140 Base resin layer

Claims

1. A film laminate comprising, in this order, a transparent resin layer, an ultraviolet-curable adhesive layer, an ultraviolet-curable printing layer, and a base resin layer, wherein both the adhesive layer and the printing layer have a cured product of an ultraviolet-curable resin, and at least one of the adhesive layer and the printing layer has an isocyanate and a cured product of an ultraviolet-curable resin.

2. The laminate according to claim 1, wherein the lamination strength of the film laminate is 3.0 N / 15 mm or more.

3. The laminate according to claim 1 or 2, wherein the transparent resin layer is an outer sealant layer.

4. The laminate according to any one of claims 1 to 3, wherein the ultraviolet-curable resin is an acrylic resin.

5. The laminate according to any one of claims 1 to 4, wherein the ultraviolet-curable printing layer is a flexographic ink layer.

6. The laminate according to any one of claims 1 to 5, wherein the isocyanate is a polyisocyanate.

7. The laminate according to any one of claims 1 to 6, which is a laminate for a laminate tube container.

8. A laminate tube container having the laminate described in claim 7.

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