JP2020044658A - Ink receiving layer, receptor film, graphic film, license plate and method for producing the same - Google Patents

Abstract

To provide an ink receiving layer having printability and excellent in low-temperature impact resistance, and a receptor film and a graphic film containing such an ink receiving layer.SOLUTION: According to an embodiment of the present disclosure, an ink receiving layer has aqueous acryl polyurethane core shell emulsion particles.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an ink receiving layer, a receptor film, a graphic film, a license plate, and a method for manufacturing the same.

  A license plate provided with decoration (also referred to as a “license plate”; the same applies in the present disclosure) is used. The decoration is performed by painting the base plate, printing on the base plate, or attaching a graphic film to the base plate. Decoration using graphic films is expected to be more widely used in decoration applications for license plates, because of its high design and excellent environmental load during production.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 2006-215672) discloses a license plate graphic film including a base film layer having an upper surface and a lower surface, and a pressure-sensitive adhesive layer disposed on a lower surface of the base film layer. The pressure-sensitive adhesive layer comprises: (a) a sticky (meth) acryl-based polymer having a carboxyl group having a glass transition temperature of −50 ° C. or less; and (b) an amino group containing no monomer unit derived from an aromatic vinyl monomer. (C) rosin ester type, hydrogenated rosin type, terpene phenol type, styrene type, hydrogenated terpene phenol type, aromatic modified hydrogenated terpene resin, and aromatic modified At least one tackifier selected from the group consisting of terpene resins, and (d) the carboxyl group-containing tackiness (meta) 10 parts by mass or more of a white pigment with respect to 100 parts by mass of the acrylic polymer, the dispersant containing the amino group-containing (meth) acrylic polymer containing no monomer unit derived from the aromatic vinyl monomer, and the tackifier. Including, graphic films ".

  Patent Document 2 (Japanese Patent Application Laid-Open No. 2017-177481) discloses a "graphic film for a license plate including a polyurethane surface protective layer to which a printing layer is applied, wherein the polyurethane surface protective layer has at least a polyester skeleton or a polycarbonate skeleton. And a reactant of a polyol having any one of the above and a polyfunctional aliphatic isocyanate, or a graphic film for a license plate, comprising an aqueous polyurethane.

JP-A-2006-215672 JP 2017-177481 A

  It is desirable that graphic films used outdoors have impact resistance at low temperatures. For example, when a graphic film that does not have low-temperature impact resistance is used for a license plate, if pebbles or the like hit the license plate in winter when the ambient temperature drops to below freezing and further to about -20 ° C, perforations or cracks may occur in the graphic film. May occur.

  The low-temperature impact resistance of a graphic film depends not only on the outermost layer of the graphic film but also on the physical properties of the internal layers constituting the graphic film. Graphic films generally include an ink-receiving layer that carries a graphic image therein. A polyvinyl chloride film, an acrylic film, or the like is used as the ink receiving layer, but the low-temperature impact resistance of these materials is not sufficient.

  The present disclosure provides an ink receiving layer having printability and excellent low temperature impact resistance, and a receptor film and a graphic film including such an ink receiving layer.

  According to one embodiment of the present disclosure, there is provided an ink receiving layer comprising water-based acrylic polyurethane core-shell emulsion particles.

  According to another embodiment of the present disclosure, an ink receiving method comprising: applying a composition comprising a water-based acrylic polyurethane core-shell emulsion to a surface to form a coating layer; and drying or curing the coating layer. A method for manufacturing a layer is provided.

  According to yet another embodiment of the present disclosure, there is provided a receptor film including the ink receiving layer and the adhesive layer.

  According to yet another embodiment of the present disclosure, comprising the receptor film, a graphic image layer disposed on the ink receiving layer of the receptor film, and a top layer disposed on or above the receptor film. A graphic film is provided.

  According to yet another embodiment of the present disclosure, there is provided a license plate including the graphic film and a base plate.

  According to yet another embodiment of the present disclosure, providing a base plate; applying the graphic film on or above the base plate to form a graphic film laminate plate; And a step of applying a printing layer to a convex portion or a concave portion of the embossed or debossed graphic film laminated plate.

  The ink receiving layer of the present disclosure has printability and is excellent in impact resistance at low temperatures, for example, at 0 ° C. to −20 ° C. Therefore, the receptor film and the graphic film including the ink-receiving layer of the present disclosure are suitable for decoration of articles used outdoors, such as license plates, traffic signs, signboards, automobiles, and decoration of exterior walls of buildings. Can be used.

  The above description should not be deemed to disclose all embodiments of the present invention and all advantages relating to the present invention.

1 is a schematic cross-sectional view of a graphic film according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view illustrating a procedure for manufacturing a license plate according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view illustrating a procedure for manufacturing a license plate according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view illustrating a procedure for manufacturing a license plate according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view illustrating a procedure for manufacturing a license plate according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view illustrating a procedure for manufacturing a license plate according to an embodiment of the present disclosure.

  Hereinafter, the present invention will be described in more detail with reference to the drawings for the purpose of illustrating typical embodiments of the present invention, but the present invention is not limited to these embodiments. Regarding reference numbers in the drawings, like-numbered elements in different drawings indicate similar or corresponding elements.

  In the present disclosure, “film” also includes an article called “sheet”.

  In the present disclosure, “pressure-sensitive adhesive” means that the adhesive is permanently tacky in a temperature range of use, for example, in a range of 0 ° C. or more and 50 ° C. or less, adheres to various surfaces with light pressure, and undergoes a phase change (from liquid to liquid). (To a solid).

  In the present disclosure, “transparent” means that a material or an article has a total light transmittance of about 85% or more in a wavelength range of 400 to 700 nm. The total light transmittance is determined based on JIS K7361-1: 1997 (ISO 13468-1: 1996).

  In the present disclosure, “(meth) acryl” means acryl or methacryl, and “(meth) acrylate” means acrylate or methacrylate.

  By "non-PVC based" in the present disclosure, it is meant that the ink receiving layer, the receptor film and the graphic film are substantially free of polyvinyl chloride, for example, a polyvinyl chloride film or a polyvinyl chloride layer. In some embodiments, the polyvinyl chloride content of the ink receiving layer, the receptor film, and the graphic film is no more than about 1%, no more than about 0.5%, or no more than about 0.1% by weight.

In the present disclosure, “non-yellowing” refers to a material which does not substantially discolor when exposed to an outdoor vertical surface for 5 years or more, or a polymer formed using the material. "Substantial discoloration does not occur" means that the color difference ΔE ^* ab when measuring the chromaticity of a non-yellowing material or polymer in the CIE (International Commission on Illumination) 1976 L ^* a ^* b ^* color system. , About 5 or less, preferably about 4 or less, more preferably about 3 or less.

  In one embodiment, the ink-receiving layer includes water-based acrylic polyurethane core-shell emulsion particles. In one embodiment, the ink-receiving layer is formed by applying a composition containing a water-based acrylic polyurethane core-shell emulsion, and optionally a cross-linking agent, additives, etc. onto a surface of a release-treated liner, a polymer film, or the like. After forming the layer, the coating layer is formed by drying or curing.

  The water-based acrylic polyurethane core-shell emulsion is composed of a (meth) acrylic resin core and a polyurethane shell located around the core, or a polyurethane acrylic core and a (meth) acrylic resin shell located around the core. Comprising emulsion particles (micelles) dispersed in an aqueous medium. The core-shell structure of the emulsion particles can be observed with an electron microscope (TEM) or the like using the difference in the dyeing properties of the polyurethane and the (meth) acrylic resin.

  Without being bound by any theory, in the formed ink receiving layer, some of the emulsion particles are at least partially fused or adhered to other emulsion particles to form a layer, but have a core-shell structure. Some of them remain as emulsion particles. The (meth) acrylic resin and the polyurethane constituting the emulsion particles are dispersed in the ink receiving layer in a size corresponding to the particle size of the emulsion particles. Thereby, it is considered that an ink receiving layer having both the printability of the (meth) acrylic resin and the low-temperature impact resistance of the polyurethane can be obtained.

  The above effects cannot be obtained by simply blending, for example, a urethane emulsion and an acrylic emulsion. Since the urethane emulsion and the acrylic emulsion have different chemical properties, the bonding force between these emulsion particles is low, and they are not completely miscible only by blending. For this reason, the ink receiving layer has low integrity, and may cause haze. On the other hand, when the ink receiving layer is formed using an acrylic urethane copolymer, for example, an acrylic urethane block copolymer, the acrylic urethane copolymer has, as one material, intermediate properties between (meth) acrylic resin and polyurethane. Therefore, both printability and low-temperature impact resistance cannot be simultaneously provided to the ink receiving layer at a high level.

  In one embodiment, the ink-receiving layer formed by using the water-based acrylic polyurethane core-shell emulsion has emulsion particles having a core-shell structure remaining, but a sea-island containing (meth) acrylic resin domains dispersed in a polyurethane matrix. The maximum diameter of the (meth) acrylic resin domain is about 1 nm or more, about 5 nm or more, or about 10 nm or more, about 1000 nm or less, about 800 nm or less, or about 500 nm or less. "Maximum diameter" means the Krumbein diameter (maximum diameter in a fixed direction).

  In another embodiment, the emulsion particles having a core-shell structure remain in the ink-receiving layer formed using the water-based acrylic polyurethane core-shell emulsion, but include polyurethane domains dispersed in a (meth) acrylic resin matrix. A sea-island structure is also included, and the maximum diameter of the polyurethane domain is about 1 nm or more, about 5 nm or more, or about 10 nm or more, about 1000 nm or less, about 800 nm or less, or about 500 nm or less.

  The water-based acrylic polyurethane core-shell emulsion is prepared, for example, by subjecting a polyol and a polyisocyanate to a condensation reaction in the presence of a (meth) acrylate monomer to form a prepolymer, and adding water to a mixed solution containing the prepolymer. The emulsion can be formed by phase emulsification to form an emulsion, optionally adding a polymerizable monomer to the emulsion, and emulsion-polymerizing the (meth) acrylate monomer and any polymerizable monomer.

  As the polyol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,3- Butanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, glycerin, diethylene glycol, trimethylene glycol, triethylene glycol Low-molecular-weight polyols having 2 to 20 carbon atoms such as tetraethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexanedimethanol, methylpentanediol adipate; methyl (meth) acrylate, n-butyl (meth) acrylate, 2- Hydroxyl-free (meth) acrylates such as tylhexyl (meth) acrylate and ethylene glycol (meth) acrylate diester, and hydroxyl-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and ethylene glycol methacrylate monoester (Meth) acrylic polyol which is a copolymer; polyurethane polyol; polycaprolactone diol, polycaprolactone triol, a condensate of the above low molecular weight polyol having 2 to 20 carbon atoms with an aliphatic or aromatic polycarboxylic acid, for example, polyethylene Polyester polyols such as adipate, polypropylene adipate, polybutylene adipate, polyhexamethylene adipate, polybutylene sebacate; polybutylene carbonate, polyhexamethylene car , Poly (3-methyl-1,5-pentylene) carbonate, poly (1,4-dimethylcyclohexylene) carbonate, polydiethylene glycol carbonate, polytetraethylene glycol carbonate, polycarbonate polyol such as polydipropylene glycol carbonate; polyethylene glycol; Polypropylene glycol, polytetramethylene glycol, their propylene oxide adducts, propylene oxide adducts of glycerin, propylene oxide adducts of saccharides such as sorbitol and sucrose, and propylene oxide adducts of compounds having active hydrogen such as ethylenediamine Ether polyols and the like can be used. Non-yellowing can be imparted to the ink receiving layer by using an aliphatic compound or an alicyclic compound as the polyol.

  Examples of the polyisocyanate include aliphatic polyisocyanates such as 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate; isophorone diisocyanate, trans and / or Alicyclic polyisocyanates such as cis-1,4-cyclohexane diisocyanate, norbornene diisocyanate, hydrogenated diphenylmethane diisocyanate; 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate; Aromatic polyisocyanates such as 4'-diphenylmethane diisocyanate and 2,2'-diphenylmethane diisocyanate; Sex body, it is possible to use polyisocyanates such as isocyanurate modified product, a carbodiimide modified product or adduct modified product. The polyisocyanate is desirably non-yellowing, and examples of such polyisocyanates include aliphatic polyisocyanates, alicyclic polyisocyanates, and modified products thereof. The polyisocyanate may be a blocked isocyanate blocked by a blocking agent.

  It is advantageous that the prepolymer has a carboxyl group or a sulfonic acid group in that a stable emulsion can be formed during phase inversion emulsification. By including a polyol having a carboxyl group or a sulfonic group in the polyol, a carboxyl group or a sulfonic group can be introduced into the prepolymer. As a polyol having a carboxyl group, dimethylolacetic acid, dimethylolpropionic acid, dimethylolbutanoic acid, dimethylolheptanoic acid, dimethylolnonanoic acid, alkanolcarboxylic acid compounds having 1 to 10 carbon atoms such as dihydroxybenzoic acid, polyoxypropylene triol And a half ester compound of maleic anhydride or phthalic anhydride. Examples of the polyol having a sulfonic acid group include an ethylene glycol adduct of 5-sulfoisophthalic acid.

  As (meth) acrylate ester monomers, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, n-pentyl (meth) acrylate, alkyl (meth) acrylates such as n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, nonyl (meth) acrylate, and lauryl (meth) acrylate; methoxyethyl (meth) acrylate; Alkoxyalkyl (meth) acrylates such as methoxybutyl (meth) acrylate and ethoxybutyl (meth) acrylate; cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isovol Alicyclic (meth) acrylate esters such as Le (meth) acrylate. Since the (meth) acrylate ester monomer has no active hydrogen, it does not react with the isocyanate group of the polyisocyanate, and functions as a diluent for adjusting the viscosity of the reaction solution in the step of forming the prepolymer.

  The equivalent ratio (NCO / OH) between the NCO groups of the polyisocyanate and the hydroxyl groups of the polyol can be about 0.7 or more, or about 0.9 or more, about 2 or less, or about 1.2 or less.

  The condensation reaction between the polyisocyanate and the polyol is generally performed at about 50C to about 100C for about 0.1 hour to about 10 hours. As the condensation catalyst, an organic tin compound such as dibutyltin dilaurate, dibutyltin dioctoate or stannasoctoate, or a tertiary amine compound such as triethylamine or triethylenediamine may be used. The reaction solution may contain an aprotic solvent such as dioxane, acetone, methyl ethyl ketone, dimethylformamide, dimethylacetamide, and N-methyl-2-pyrrolidone. In order to prevent polymerization of the (meth) acrylic acid ester monomer, a polymerization inhibitor such as p-methoxyphenol may be added to the reaction solution, and the prepolymer may be formed in the presence of oxygen, for example, air.

  Phase inversion emulsification of the mixture containing the produced prepolymer is carried out by adding water to the mixture and, if necessary, an emulsifier such as an anionic, cationic or zwitterionic surfactant or a nonionic surfactant. And a forced emulsifier such as a stirrer equipped with a stirring blade or a homomixer, a homogenizer, a disper, or a line mixer.

  When a polyol having a carboxyl group or a sulfonic acid group is used, a self-emulsifying property is imparted to the prepolymer by neutralizing the carboxyl group or the sulfonic acid group incorporated in the prepolymer during phase inversion emulsification, so that the prepolymer is stable. The resulting emulsion can be formed. As a neutralizing agent, tertiary alkanolamines such as dimethylethanolamine, methyldiethanolamine, diethylethanolamine, ethyldiethanolamine, diethyltriisopropanolamine, ethyldiisopropanolamine, and triisopropanolamine; sodium hydroxide, potassium hydroxide, and magnesium hydroxide And inorganic hydroxides such as calcium hydroxide, barium hydroxide and cesium hydroxide; and alkaline inorganic salts such as sodium hydrogen carbonate, sodium carbonate, potassium hydrogen carbonate and calcium carbonate.

  Examples of the optional polymerizable monomer that can be added to the formed emulsion include the above (meth) acrylate ester monomers; vinyl monomers such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, and p-methylstyrene. 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, phenoxyhydroxypropyl (meth) acrylate, cyclohexanedimethanol mono (meth) acrylate, polycaprolactone mono (meth) ) Acrylate, polytetramethylene ether mono (meth) acrylate, trimethylolpropane mono (meth) acrylate, trimethylolpropane di (meth) acrylate, dipropylene glycol Hydroxyl group-containing (meth) such as (meth) acrylate, glycerin mono (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol mono (meth) acrylate, pentaerythritol di (meth) acrylate, and pentaerythritol tri (meth) acrylate Acrylates are mentioned. The hydroxyl group of the hydroxyl group-containing (meth) acrylate can function as a cross-linking point with an optional cross-linking agent, and contributes to the improvement of the strength of the ink receiving layer.

  Emulsion polymerization of the (meth) acrylate monomer and any polymerizable monomer can be carried out by adding a polymerization initiator to the emulsion and, if necessary, heating.

  Persulfates such as ammonium persulfate, potassium persulfate, and sodium persulfate; and polymerization initiators such as 2,2'-azobisisobutyronitrile and 2,2'-azobis (2,4-dimethylvaleronitrile). Azo compounds; hydrogen peroxide compounds such as hydrogen peroxide and t-butyl hydroperoxide; and radical polymerization initiators such as peroxides such as benzoyl peroxide and lauroyl peroxide. A redox polymerization initiator in which a radical polymerization initiator is combined with a reducing agent such as sodium sulfite, sodium hydrogen sulfite, sodium thiosulfate, tartaric acid, L-ascorbic acid and the like can also be used.

  Emulsion polymerization is generally performed at about 50C to about 100C for about 1 hour to about 20 hours. A chain transfer agent such as octyl mercaptan, lauryl mercaptan, 2-mercaptoethanol, tert-dodecyl mercaptan, or thioglycolic acid is used to adjust the molecular weight in the emulsion polymerization of the (meth) acrylate monomer and any polymerizable monomer. May be.

  The solid content of the water-based acrylic polyurethane core-shell emulsion thus obtained is generally about 5% by weight or more, about 10% by weight or more, or about 15% by weight or more, about 60% by weight or less, about 50% by weight or less, or It is about 40% by mass or less.

  The average particle size of the emulsion particles of the water-based acrylic polyurethane core-shell emulsion is generally about 10 nm or more, about 20 nm or more, or about 40 nm or more, about 500 nm or less, about 300 nm or less, or about 200 nm or less. By setting the average particle size of the emulsion particles in the above range, the degree of dispersion of the polyurethane and the (meth) acrylic resin in the ink receiving layer can be made suitable for both low-temperature impact resistance and printability.

  In one embodiment, the mass ratio of the polyurethane and the (meth) acrylic resin constituting the emulsion particles is polyurethane / (meth) acrylic resin = 10/90 to 90/10, 25/75 to 75/25, or 40 / It is in the range of 60-60 / 40. By setting the mass ratio of the polyurethane to the (meth) acrylic resin within the above range, both the low-temperature impact resistance and the printability of the ink receiving layer can be balanced at a high level.

  As the combination of polyurethane and (meth) acrylic resin, a combination of hard polyurethane and soft (meth) acrylic resin, or a combination of soft polyurethane and hard (meth) acrylic resin can be used. This is advantageous in improving both of the handleability in the method. Hard polyurethanes have a glass transition temperature in the range of 0-150C. Soft polyurethane has a glass transition temperature in the range of -80 to 0C. Hard (meth) acrylic resins have a glass transition temperature in the range of 0-150C. Soft (meth) acrylic resins have a glass transition temperature in the range of -80 to 0C. The glass transition temperature is determined by a dynamic viscoelasticity measurement, a tensile mode, a frequency of 10.0 Hz, a heating rate of 5.0 ° C./min, and a loss tangent tanδ (tan δ) when the viscoelasticity is measured in a temperature range of −100 to 200 ° C. = Loss modulus E "/ storage modulus E ').

  The glass transition temperature of the polyurethane can be adjusted depending on the polyol, the polyisocyanate used, and the density of the generated urethane groups. As the hard polyurethane, to increase the density of urethane groups, for example, a low molecular weight polyol having 2 to 20 carbon atoms as a polyol, a polyether formed using an alicyclic or aromatic polyisocyanate, polyester Or polycarbonate polyurethane is mentioned. As a soft polyurethane, so as to lower the density of urethane groups, for example, a polyether formed using a low molecular weight polyol having 2 to 20 carbon atoms and an aliphatic polyisocyanate as a polyol, polyester or polycarbonate polyurethane, as a polyol Polyether, polyester or polycarbonate polyurethane formed by using a high molecular weight polyether polyol having a molecular weight of 500 or more, a high molecular weight polyester polyol, and a high molecular weight polycarbonate polyol. Examples of the hard (meth) acrylic resin include a copolymer based on methyl methacrylate. Examples of the soft (meth) acrylic resin include an alkyl (meth) acrylate-based copolymer having 4 to 20 carbon atoms in the alkyl group.

  In one embodiment, the emulsion particles of the water-based acrylic polyurethane core-shell emulsion include at least one selected from the group consisting of polyether polyurethane, polyester polyurethane, and polycarbonate polyurethane. Polyether polyurethane, polyester polyurethane, and polycarbonate polyurethane can be obtained by using polyether polyol, polyester polyol, and polycarbonate polyol as the polyol, respectively.

  In one embodiment, the emulsion particles of the water-based acrylic polyurethane core-shell emulsion are a group consisting of a homopolymer of methyl methacrylate and a copolymer of methyl (meth) acrylate and an alkyl (meth) acrylate having 4 to 20 carbon atoms in the alkyl group. At least one selected from the following.

  A crosslinker may be added to the water-based acrylic polyurethane core-shell emulsion to crosslink the emulsion particles. As the crosslinking agent, the above-mentioned polyisocyanate used for producing the prepolymer may be used, or an aqueous crosslinking agent such as a carbodiimide compound, a blocked isocyanate, an epoxy compound, a melamine compound, and an aminoplast compound may be used.

  The addition amount of the crosslinking agent is about 0.01 parts by weight or more, about 0.02 parts by weight or more, or about 0.05 parts by weight or more, about 50 parts by weight, based on 100 parts by weight of the solid content of the aqueous acrylic polyurethane core-shell emulsion. Parts by weight, about 40 parts by weight or less, or about 30 parts by weight or less.

  As an optional component, additives such as a solvent, an ultraviolet absorber, an antioxidant, a dispersant, a light stabilizer, a lubricant, and a plasticizer may be added to the water-based acrylic polyurethane core-shell emulsion.

  The thickness of the ink receiving layer is generally at least about 2 μm, at least about 5 μm, or at least about 10 μm. By setting the thickness of the ink receiving layer within the above range, the ink receiving layer can be given the strength required for printing. The thickness of the ink receiving layer is generally about 150 μm or less, about 120 μm or less, or about 100 μm or less. By setting the thickness of the ink receiving layer to the above range, it is possible to reliably receive the ink and ensure the sharpness of the graphic image layer, and to function the ink receiving layer as a receptor film or a support of the graphic film. Can be.

  The ink receiving layer may be colored white or another color using a pigment, and may be transparent. Pigments include carbon blacks such as furnace black, channel black, thermal black, and acetylene black, black iron oxide, yellow iron oxide, red iron oxide, ultramarine, navy blue, cobalt blue, titanium yellow, turquoise, molybdate orange, titanium oxide, etc. Inorganic pigments, or C.I. I. Pigment White 6, C.I. I. Pigment Black 7, C.I. I. Pigment Red 122, 202, 254, 255, C.I. I. Pigment Orange 43, C.I. I. Pigment Violet 19, 23, C.I. I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, C.I. I. Pigment Brown 23, 25, C.I. I. Pigment Yellow 74, 109, 110, 128, C.I. I. Organic pigments such as CI Pigment Green 7 and 36 can be used.

  In one embodiment, the loss tangent tan δ (= loss modulus E ″ / storage modulus E ′) of the ink-receiving layer is about −20 ° C. at -20 ° C. when measured in a tensile mode at a frequency of 10.0 Hz. 0.1 or more, about 0.12 or more, or about 0.15 or more, about 3.0 or less, about 2.5 or less, or about 2.0 or less. By setting the ratio to 1 or more, excellent low-temperature impact resistance can be imparted to the ink-receiving layer, and by setting the loss tangent tan δ of the ink-receiving layer to about 3.0 or less, the ink-receiving layer can have a sufficient tangent at room temperature. Strength can be imparted.

In one embodiment, the storage modulus E 'of the ink receiving layer is greater than or equal to about 1 x 10 ⁷ Pa and about 2 x 10 ⁷ Pa at 25 ° C when viscoelasticity measurements are performed in the tensile mode at a frequency of 10.0 Hz. Or more, about 5 × 10 ⁷ Pa or more, about 5 × 10 ⁸ Pa or less, about 3 × 10 ⁸ Pa or less, or about 2 × 10 ⁸ Pa or less. By setting the storage elastic modulus E ′ of the ink receiving layer to about 1 × 10 ⁷ Pa or more, sufficient printability can be imparted to the ink receiving layer. By setting the storage elastic modulus E ′ of the ink receiving layer to about 5 × 10 ⁸ Pa or less, the strength and handleability of the ink receiving layer at room temperature can be increased.

  In one embodiment, the receptor film includes the ink receiving layer and the adhesive layer. The receptor film may include a substrate layer between the ink receiving layer and the adhesive layer.

  Examples of the adhesive that can be used for the adhesive layer include, but are not limited to, the following: (meth) acrylic polymers, natural rubber, butyl rubber, isobutyl rubber, synthetic rubber such as SBR, polyester, polyether, silicone, Uses adhesives or heat-sensitive adhesives, including tacky polymers such as polyurethane or heat-sensitive adhesive polymers, and additives such as tackifiers, antioxidants, UV absorbers, fillers, and plasticizers as needed can do. The adhesive may be thermally cross-linked by a cross-linking agent or cross-linked by radiation (for example, electron beam or ultraviolet light).

  The thickness of the adhesive layer can vary, and generally can be about 3 μm or more, about 5 μm or more, or about 10 μm or more, about 100 μm or less, about 80 μm or less, or about 50 μm or less.

  The adhesive layer may be colored white or another color using a pigment, or may be transparent. As the pigment, those described above for the ink receiving layer can be used.

  In one embodiment, at least one of the ink receiving layer and the adhesive layer is colored white. In this embodiment, the color of the surface of the adherend to which the receptor film is applied, for example, the surface of the base plate of the license plate can be hidden. Examples of white pigments used for coloring the ink receiving layer or the adhesive layer include zinc carbonate, zinc oxide, zinc sulfide, and titanium dioxide (titanium oxide). Titanium dioxide can be used particularly advantageously because of its high whiteness and excellent dispersibility. The white pigment may be particles having various shapes such as a sphere, a needle, a plate, or a flake, and is preferably a spherical particle because of its good dispersibility. The white pigment may be surface-treated with a coupling agent such as silane or titanate to further improve dispersibility. In order to enhance the dispersibility of the white pigment, a polymer dispersant such as an amino-modified acrylic polymer may be used. A pigment such as aluminum flake, carbon black, and phthalocyanine may be used in combination to improve the hiding power of the ink receiving layer or the adhesive layer and / or to adjust the hue.

The average primary particle size of the white pigment may be about 0.10 μm or more, about 0.12 μm or more, or about 0.15 μm or more, about 5.0 μm or less, about 3.0 μm or less, or about 1.0 μm or less. . By setting the average primary particle size of the white pigment in the above range, the white pigment can be more uniformly dispersed in the ink receiving layer or the adhesive layer. The average primary particle size of the white pigment is the volume cumulative particle diameter D ₅₀ which can be determined using a laser diffraction / scattering particle size distribution measurement.

  Use a film containing polyvinyl chloride, polyurethane, polyethylene, polypropylene, polycarbonate, polyester, vinyl chloride-vinyl acetate resin, acrylic resin, cellulose resin, acrylonitrile-butadiene-styrene (ABS resin) or fluororesin as the base layer. Can be.

  The graphic film of one embodiment includes the above-described receptor film, a graphic image layer disposed on the ink receiving layer of the receptor film, and a top layer disposed on or above the receptor film. The `` top layer disposed on the receptor film '' means that the top layer is disposed in direct contact with the receptor film layer, and the `` top layer disposed above the receptor film '' It means that the top layer is not in direct contact with the receptor film, but is arranged via another layer, for example, a graphic image layer, a transparent adhesive layer. The same applies to the definitions of “above” and “above” as referred to in this disclosure for other layers.

  The graphic image layer can be used to impart decorativeness or design to the graphic film. When a graphic film including a graphic image layer is used for a license plate, a pattern, a pattern, and the like can be provided to a background portion other than the numbers and characters of the license plate. Examples of the graphic image layer include a color layer exhibiting a special color, a metal color, and the like, and a pattern layer such as a grain, a stone, a logo, a picture, and the like. As a material for the graphic image layer, for example, it is possible to use an ink composition in which a pigment such as an inorganic pigment, an organic pigment, or a glitter is dispersed in a polyvinyl chloride / polyvinyl acetate mixture or a binder containing an acrylic resin. it can. In some embodiments, the graphic image layer can be formed using inkjet printing, screen printing, offset printing, electrostatic printing, gravure printing, and the like.

  In one embodiment, the graphic image layer is an inkjet printing layer that can be formed using an inkjet printing ink composition.

  The thickness of the graphic image layer can vary, and generally can be about 0.1 μm or more, or about 0.5 μm or more, about 10 μm or less, or about 5 μm or less when a solvent-based ink is used. When a UV curable ink is used, the thickness can be about 0.5 μm or more, or about 1 μm or more, about 30 μm or less, or about 20 μm or less.

  The graphic image layer may be located between the top layer and the ink receiving layer, or may be located between the ink receiving layer and the adhesive layer.

  The top layer protects the receptor film and the graphic image layer. In one embodiment, the top layer also functions as an ink receiving layer, and is formed by using an ink composition containing a pigment and a binder such as a melamine resin, an alkyd resin, a polyurethane, and a mixed resin thereof on the top layer. It is also possible to form a print layer constituting a display portion for characters and the like. The top layer can include a resin such as polyurethane, (meth) acrylic resin, polyester, and polycarbonate.

  In one embodiment, the top layer comprises polyurethane. The top layer containing polyurethane is formed by coating a reactive polyurethane composition containing a polyol and a polyisocyanate, or a polyurethane composition containing a polyurethane and an organic solvent or water, for example, knife coat, bar coat, blade coat, doctor coat, roll coat. It can be formed by applying to a liner with a cast coat or the like, and heating or drying as necessary. In a reactive polyurethane composition, a polyol reacts with a polyisocyanate during heating or drying to form a polyurethane. The top layer may be formed by a casting method using the reactive polyurethane composition or the polyurethane composition. In one embodiment, the top layer is a transparent polyurethane layer, which can enhance the visibility of the graphic image layer.

  As the polyol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,3- Butanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, glycerin, diethylene glycol, trimethylene glycol, triethylene glycol Low-molecular-weight polyols having 2 to 20 carbon atoms such as tetraethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexanedimethanol, methylpentanediol adipate; methyl (meth) acrylate, n-butyl (meth) acrylate, 2- Hydroxyl-free (meth) acrylates such as tylhexyl (meth) acrylate and ethylene glycol (meth) acrylate diester, and hydroxyl-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and ethylene glycol methacrylate monoester (Meth) acrylic polyol which is a copolymer; polyurethane polyol; polycaprolactone diol, polycaprolactone triol, a condensate of the above low molecular weight polyol having 2 to 20 carbon atoms with an aliphatic or aromatic polycarboxylic acid, for example, polyethylene Polyester polyols such as adipate, polypropylene adipate, polybutylene adipate, polyhexamethylene adipate, polybutylene sebacate; polybutylene carbonate, polyhexamethylene car , Poly (3-methyl-1,5-pentylene) carbonate, poly (1,4-dimethylcyclohexylene) carbonate, polydiethylene glycol carbonate, polytetraethylene glycol carbonate, polycarbonate polyol such as polydipropylene glycol carbonate; polyethylene glycol; Polypropylene glycol, polytetramethylene glycol, their propylene oxide adducts, propylene oxide adducts of glycerin, propylene oxide adducts of saccharides such as sorbitol and sucrose, and propylene oxide adducts of compounds having active hydrogen such as ethylenediamine Ether polyols and the like can be used. The polyol is generally an aliphatic or alicyclic compound, which can impart non-yellowing to the top layer.

  Aliphatic polyisocyanates such as 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate; isophorone diisocyanate, trans and / or It is possible to use alicyclic polyisocyanates such as cis-1,4-cyclohexane diisocyanate, norbornene diisocyanate, hydrogenated diphenylmethane diisocyanate, and non-yellowing polyisocyanates such as buret-modified, isocyanurate-modified or adduct-modified thereof. it can. The polyisocyanate may be a blocked isocyanate blocked by a blocking agent.

  The equivalent ratio (NCO / OH) between the NCO groups of the polyisocyanate and the hydroxyl groups of the polyol can be about 0.7 or more, or about 0.9 or more, about 2 or less, or about 1.2 or less.

  The reactive polyurethane composition may include a catalyst. As the catalyst, those generally used for forming polyurethane, for example, di-n-butyltin dilaurate, zinc naphthenate, zinc octenoate, triethylenediamine and the like can be used. The amount of the catalyst used is generally about 0.005 parts by weight or more, or about 0.01 parts by weight or more, about 0.5 parts by weight or less, or about 0.2 parts by weight or less based on 100 parts by weight of the composition. .

  Reactive polyurethane compositions and polyurethane compositions include, for example, methyl ethyl ketone, methyl isobutyl ketone, ketones such as acetylacetone, toluene, aromatic hydrocarbons such as xylene, ethanol, isopropyl alcohol, etc. for the purpose of improving workability and coatability. Organic solvents such as alcohols, esters such as ethyl acetate and butyl acetate, and ethers such as tetrahydrofuran, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate and dipropylene glycol monomethyl ether acetate. The amount of the organic solvent used is generally about 1 part by weight or more, or about 5 parts by weight or more, about 90 parts by weight or less, or about 80 parts by weight or less based on 100 parts by weight of the composition.

  The polyurethane composition may be an aqueous polyurethane composition containing water as a solvent. The polyurethane contained in the aqueous polyurethane composition may have a chain extender component such as diamines, and an anionic group such as a carboxyl group and a sulfonic acid group. The aqueous polyurethane composition may include an aqueous crosslinking agent, an emulsifier, and the like.

  The top layer is made of polyester polyol or polycarbonate from the viewpoints of weather resistance, chemical resistance, impact resistance, gasoline resistance, elongation characteristics that can follow press processing without heating, print compatibility with baking coating ink, and the like. It is advantageous to include a polyurethane which is a condensate of a polyol with an aliphatic or cycloaliphatic polyisocyanate.

  In some embodiments, the polyester polyol or polycarbonate polyol has a hydroxyl equivalent weight of about 40% or more, about 60% or more, or about 80% or more, 100% or less, about 40% or more of all polyols included in the reactive polyurethane composition. It can be up to 95%, or up to about 90%.

  In some embodiments, the aliphatic or cycloaliphatic polyisocyanate comprises at least about 50%, at least about 60%, or at least about 70%, at least about 100%, based on isocyanate equivalents, of the total isocyanate contained in the reactive polyurethane composition. %, About 90% or less, or about 80%.

  The glass transition temperature Tg of the top layer may be about 50 ° C. or higher, or about 60 ° C. or higher, about 100 ° C. or lower, or about 80 ° C. or lower. Tg in the present disclosure is a loss tangent tan δ (= loss elastic modulus) when viscoelasticity is measured in a tensile mode, a frequency of 10.0 Hz, a temperature rising rate of 5.0 ° C./min, and a temperature range of −40 to 200 ° C. The top layer having a glass transition temperature in the above range can impart excellent weather resistance and chemical resistance to a graphic film.

  The loss tangent tan δ of the top layer may be less than or equal to about 0.1 or less than or equal to about 0.05 at 120 ° C. when the viscoelasticity is measured in a shear mode at a frequency of 0.01 Hz. The top layer having the loss tangent tan δ in the above range can impart excellent weather resistance and chemical resistance to the graphic film.

  The top layer, as other optional components, a benzotriazole compound, a hydroxyphenyltriazine compound, an ultraviolet absorber such as a cyanoacrylate compound, a light stabilizer such as a hindered amine compound, a heat stabilizer, a dispersant, a plasticizer, a flow improver, An additive such as a leveling agent may be included.

  The thickness of the top layer is generally at least about 3 μm, at least about 5 μm, or at least about 10 μm. By setting the thickness of the top layer within the above range, weather resistance and chemical resistance can be imparted to the graphic film. The thickness of the top layer is generally less than about 100 μm, less than about 80 μm, or less than about 50 μm. By setting the thickness of the top layer to the above range, the low-temperature impact resistance of the graphic film can be improved, and when the graphic film is used for a license plate, the good followability to the embossed portion can be improved. Obtainable.

  By providing a transparent layer on the top layer, weather resistance, solvent resistance, chemical resistance, ink adhesion and the like can be improved. The thickness of the transparent layer is generally about 1 μm or more, about 2 μm or more, or about 3 μm or more, about 20 μm or less, about 10 μm or less, or about 5 μm or less.

  A transparent adhesive layer may be disposed between the top layer and the receptor film. The adhesive that can be used for the transparent adhesive layer is not limited to the following, but includes, for example, (meth) acrylic polymers, natural rubber, butyl rubber, isobutyl rubber, synthetic rubber such as SBR, polyester, polyether, and silicone. Adhesives or heat-sensitive adhesive polymers, such as polyurethane, and, if necessary, additives such as tackifiers, antioxidants, ultraviolet absorbers, fillers, plasticizers, and the like. Can be used. The adhesive may be thermally cross-linked by a cross-linking agent or cross-linked by radiation (for example, electron beam or ultraviolet light).

  The thickness of the transparent adhesive layer can vary, and generally can be about 3 μm or more, about 5 μm or more, or about 10 μm or more, about 80 μm or less, about 50 μm or less, or about 30 μm or less. Thereby, the followability of the graphic film to the embossed portion and the impact resistance at a low temperature can be further improved.

  In one embodiment, the graphic film is non-PVC based. According to this embodiment, it is possible to achieve polyvinyl chloride (PVC) free for green procurement corresponding to environmental problems.

  FIG. 1 shows a schematic sectional view of a graphic film 10 according to one embodiment. The graphic film 10 includes an over-lamination film 20 and a receptor film 30. The over laminate film 20 includes (a1) a top layer 22 and (a2) a transparent adhesive layer 24. The receptor film 30 includes (b1) a graphic image layer 32, (b2) an ink receiving layer 34, and (b3) an adhesive layer 36. The over laminate film 20 is laminated on the receptor film 30 via the transparent adhesive layer 24.

  As shown in FIG. 1, the top layer 22 and the transparent adhesive layer 24 may be directly bonded, or may be bonded via a bonding layer. The top layer 22 may have a surface treatment such as a primer treatment or a corona treatment on an adhesion surface with the transparent adhesive layer 24.

  As shown in FIG. 1, the ink receiving layer 34 and the adhesive layer 36 may be directly bonded, or may be bonded via a bonding layer. The ink receiving layer 34 may have a surface treatment such as a primer treatment or a corona treatment on the adhesion surface with the adhesion layer 36.

  The graphic film may have a retroreflective layer between the ink receiving layer and the adhesive layer of the receptor film. In this embodiment, it is advantageous for the retroreflective layer to exhibit the retroreflective performance if the ink receiving layer is transparent. The retroreflective layer can include beads or cube-corner elements configured to reflect incident light back to the light emitting source.

  The thickness of the retroreflective layer can vary, and generally can be about 40 μm or more, or about 50 μm or more, about 100 μm or less, or about 60 μm or less.

  The retroreflective layer and the ink receiving layer may be bonded via a transparent bonding layer. The transparent bonding layer can be formed using the same adhesive or pressure-sensitive adhesive as the transparent adhesive layer. The thickness of the transparent bonding layer can be generally about 1 μm or more, or about 2 μm or more, about 30 μm or less, or about 15 μm or less.

  In embodiments where the graphic film has a retroreflective layer, any layer of the graphic film that is on the path of light incident and reflected by the graphic film may be an infrared absorber, such as cesium tungsten oxide (CWO), an oxide, It may contain a whiteness improving material such as titanium, zinc oxide and a fluorescent whitening agent.

  The graphic film may have a liner on the top layer and / or the adhesive layer for the purpose of protecting the top layer and / or the adhesive layer during production, transportation, storage or use.

  Examples of the liner include paper; plastic materials such as polyethylene, polypropylene, polyester, and cellulose acetate; and laminated paper coated with such plastic materials. These liners may have a surface that has been release-treated with silicone or the like. The thickness of the liner can generally be about 5 μm or more, about 15 μm or more, or about 25 μm or more, about 300 μm or less, about 200 μm or less, or about 150 μm or less.

  In one embodiment, the thickness of the graphic film is no more than about 200 μm, no more than about 180 μm, or no more than about 150 μm. The thickness of the graphic film does not include the thickness of the liner. In this embodiment, the ability to follow the embossed portion when the graphic film is used for the license plate can be further improved.

  In one embodiment, the thickness of the graphic film is at least about 50 μm, at least about 60 μm, or at least about 80 μm. In this embodiment, the strength required for the license plate application can be imparted to the graphic film.

  The graphic film advantageously has a breaking strength of about 5 N / 25 mm or more, about 10 N / 25 mm or more, or about 20 N / 25 mm or more from the viewpoint of durability. The graphic film advantageously has a breaking strength of about 200 N / 25 mm or less, about 175 N / 25 mm or less, or about 150 N / 25 mm or less from the viewpoint of manufacturability. In the present disclosure, the breaking strength is a value measured in accordance with JIS Z 0237.

  The graphic film has a 5% elongation tension of about 60 N / 25 mm or less, or about 50 N / 25 mm or less, from the viewpoint of preventing cracks from occurring during embossing or debossing during the production of the license plate, and preventing floating from the base plate. It is advantageous. Advantageously, the graphic film has a 5% elongation tension of about 1 N / 25 mm or more, or about 2 N / 25 mm or more from the viewpoint of mechanical strength. In the present disclosure, the 5% elongation tension is a value measured according to JIS Z 0237.

  The graphic film of one embodiment has excellent low-temperature impact resistance. In this embodiment, when the impact resistance test is performed at a test temperature of 0 ° C., −10 ° C., or −20 ° C. according to JIS K5600-5-3 (ASTM D 2794), the film does not crack. . The impact resistance test was performed using an IM-201 DuPont (registered trademark) type tester (Tester Sangyo Co., Ltd.) with a weight of 500 gf, a drop height of 500 mm, and a shooting core diameter of 6.35 mm. It is done by dropping and checking the appearance.

  The graphic film can be manufactured, for example, by the following method. An ink-receiving layer is formed using a water-based acrylic polyurethane core-shell emulsion on a liner having a release treatment. Next, an adhesive is applied and dried on a liner having a release treatment to form an adhesive layer. The ink receiving layer and the adhesive layer are opposed to each other and bonded to each other to produce a receptor film sandwiched between liners. The liner on the ink receiving layer of the receptor film is removed, and a graphic image layer is formed on the ink receiving layer by ink jet printing or the like, thereby producing a receptor film carrying a graphic image.

  A top layer is formed on a liner having a release treatment. Next, a transparent adhesive is applied on a liner having a release treatment and dried to form a transparent adhesive layer. The top layer and the transparent adhesive layer are attached to each other so as to face each other, and the liner is removed, thereby producing an over-laminated film. A transparent adhesive may be applied directly on the top layer and dried to form a transparent adhesive layer, thereby producing an over-laminated film.

  A graphic film can be obtained by laminating the overlaminated film to the receptor film such that the transparent adhesive layer of the overlaminated film faces the graphic image layer of the receptor film.

  As a coating means, a usual coater, for example, a bar coater, a knife coater, a roll coater, a die coater, a gravure coater or the like can be used. The top layer composition can be formed into a film by melt extrusion or the like, and bonded to the transparent adhesive layer to produce an over-laminated film.

  In one embodiment, there is provided a graphic film laminated plate including the graphic film and a base plate. The graphic film laminate plate can be formed by applying a graphic film on or above the base plate. "On the base plate" means that the graphic film is applied in direct contact with the base plate, and "above the base plate" means that the graphic film does not directly contact the base plate, e.g., on the base plate. It means that it is arranged via another layer such as an undercoat layer.

  Generally, a metal plate or a resin plate can be used as the base plate. Examples of the metal plate include an aluminum plate, a stainless steel plate, and an iron plate. Examples of the resin plate include a polycarbonate plate, a polyester plate, and a vinyl chloride plate. If necessary, these plates may be formed into a shape such as a frame.

  In one embodiment, a license plate is provided that includes the graphic film and a base plate. In one embodiment, the license plate is non-reflective.

  The license plate may generally include numbers, letters, graphics, patterns, or combinations thereof. In one embodiment, the appearance of the license plate is defined by government and / or jurisdiction. In another embodiment, the display of numbers, characters, and the like can be formed using a printed layer. In still another embodiment, the display section can be formed by combining an embossed section (convex section) or a debossed section (concave section) with a printing layer. The depths of the embossed portion and the debossed portion are generally about 1 mm or more and about 2 mm or less, respectively, but are not limited to this range.

  The printing layer is formed using a solvent-based ink generally called a roll coating ink. The printing layer is formed by applying a pigment and an ink composition containing a binder such as melamine resin, alkyd resin, polyurethane, and a resin mixture thereof onto the top layer of the graphic film using roll coating, at a predetermined temperature and time. Can be formed by baking. As the ink composition, specifically, NSP-UP 401K-1 green ink (Nichiko BIX Co., Ltd.), MEG screen ink (Teiku Ink Manufacturing Co., Ltd.) which is a one-component heat-curable ink, and the like can be used. it can.

  In one embodiment, a method of manufacturing a license plate includes providing a base plate, forming a graphic film laminate plate on or above the base plate by applying the graphic film described above, and embossing the graphic film laminate plate. Processing or debossing, and forming a printing layer on the projections or depressions of the embossed or debossed graphic film laminated plate.

  A method for manufacturing a license plate according to the present disclosure will be exemplarily described with reference to FIGS. 2A to 2E, but the method for manufacturing a license plate is not limited thereto.

  The graphic film shown in FIG. 2A has a liner 40 disposed on the adhesive layer of the graphic film 10.

  As shown in FIG. 2B, the graphic film laminated plate 60 is formed by removing the liner 40, bonding the adhesive layer to a base plate 50 such as an aluminum plate and laminating the same.

  Next, as shown in FIG. 2C, using a blank press die 70, the graphic film laminated plate 60 is blank-pressed to a desired size and cut out.

  As shown in FIG. 2D, the cut-out graphic film laminated plate 60 is embossed and / or debossed at room temperature to form a display portion of the license plate and a frame portion on the periphery. In FIG. 2D, the convex portion (embossed portion) is shown as a pedestal of the display unit. The frame portion can give strength to the license plate to prevent deformation of the license plate.

  As shown in FIG. 2E, a printing layer 62 is formed on the convex portion (embossed portion) of the embossed graphic film laminated plate 60 by roll coating or the like. Thus, a license plate including the graphic film 10 can be manufactured. In one embodiment, the graphic film has excellent solvent resistance, and the printed layer can be printed and used as it is without applying a clear protective layer to the outermost surface of the license plate.

  The graphic film of the present disclosure can be applied to, for example, a traffic sign, a signboard, and the like in addition to the license plate described above. The graphic films of the present disclosure can also be used as decorative films or sheets for automobiles or buildings.

  The following examples illustrate specific embodiments of the present disclosure, but the present invention is not limited thereto. All parts and percentages are by weight unless otherwise indicated.

  Table 1 shows the reagents and materials used in this example.

Example 1
Preparation of Polyurethane Top Layer (A) 1.59 parts by weight of Tinuvin® 292, 2.68 parts by weight of Tinuvin® 1130, 0.57 parts by weight of Lipal® 860K, 0.28 parts A mixed liquid was obtained by mixing 2 parts by mass of 2-amino-2-methylpropanol and 10.37 parts by mass of distilled water. 14.80 parts by mass of the mixed solution and 26.90 parts by mass of Carbodite (registered trademark) V-02 were added to 200.00 parts by mass of Eternacoll (registered trademark) UW5002 and mixed to prepare an aqueous polyurethane dispersion. . The obtained aqueous polyurethane dispersion was applied on Lumirror (registered trademark) T-60, and dried in an oven at 100 ° C. for 5 minutes to obtain a polyurethane top layer (A) having a thickness of 30 μm.

Preparation of Transparent Adhesive Layer (B) 100 parts by mass of an acrylic pressure-sensitive adhesive solution SK Dyne (registered trademark) 2094 and 0.67 parts by mass of an epoxy-based crosslinking agent E-5XM were mixed, and the above polyurethane top layer ( A) was applied on it and dried in an oven at 90 ° C. for 5 minutes to obtain a transparent adhesive layer (B) having a thickness of 30 μm.

Preparation of Ink Receiving Layer (C-1) 100 parts by mass of an acrylic-polyether polyurethane core-shell emulsion RIKA BOND (registered trademark) SU-P1885 and 1.5 parts by mass of Carbodite (registered trademark) V-02 were mixed, It was applied on a 38 μm thick release-treated polyester film Purex A55 and dried in an oven at 100 ° C. for 5 minutes to obtain an ink receiving layer (C-1) having a thickness of 35 μm.

Preparation of White Adhesive Layer (D-1) 40 parts by mass of Ti-Pure (registered trademark) R-960 were mixed with 20 parts by mass of JURYMER (registered trademark) YM-5 and 12 parts by mass of 2-butanone. The obtained mixture was mixed with 209 parts by mass of an acrylic pressure-sensitive adhesive solution Acryset (registered trademark) 8820. The obtained solution was applied on a 38 μm thick release-treated polyester film Purex A55, and dried in an oven at 100 ° C. for 5 minutes to obtain a 35 μm thick white adhesive layer (D-1).

  The white adhesive layer (D-1) was laminated with the ink receiving layer (C-1), and the release-treated polyester film for the ink receiving layer was removed. The graphic image layer was printed on the ink receiving layer (C-1) using an ink jet printer JV-33-130 (Mimaki Engineering Co., Ltd. (Tomi-shi, Nagano, Japan)). The polyurethane film (A) was laminated on the printed graphic image layer via the transparent adhesive layer (B) to obtain the graphic film of Example 1.

  The peeled polyester film on the white adhesive layer (D-1) was removed from the obtained graphic film, and the graphic film was adhered to an aluminum plate (A1050P JIS H4000, 1.0 mm × 165.5 mm × 330.5 mm). A graphic film laminated plate was obtained.

  The surface of the graphic film laminated plate is embossed with the model of the vehicle number, and NSP-UP 401K-1 green ink (Hihiro Bix Co., Ltd. (Chiyoda-ku, Tokyo)) is coated only on the convex surface of the emboss by roll coating. After drying in an oven at 135 ° C. for 10 minutes, a license plate was obtained.

Example 2
100 parts by mass of an acrylic-polyester polyurethane core-shell emulsion RIKA BOND (registered trademark) SU-P1753 and 1.5 parts by mass of Carbodite (registered trademark) V-02 are mixed and applied on a 38-μm-thick release-treated polyester film Purex A55. Then, it was dried in an oven at 100 ° C. for 5 minutes to produce a graphic film, a graphic film laminated plate and a license plate in the same procedure as in Example 1 except that an ink receiving layer (C-2) having a thickness of 35 μm was obtained. did.

Example 3
100 parts by mass of an acrylic-polycarbonate polyurethane core-shell emulsion MX-8928 and 1.5 parts by mass of Carbodilite® V-02 were mixed, applied onto a 38 μm-thick release-treated polyester film Purex A55, and heated at 100 ° C. in an oven. In this manner, a graphic film, a graphic film laminated plate, and a license plate were produced in the same procedure as in Example 1 except that the ink receiving layer (C-3) having a thickness of 35 μm was obtained by drying in an oven for 5 minutes.

Example 4
A sample was prepared in which the ink receiving layer was colored white. 75 parts by mass of Tipaque (registered trademark) CR-90 were added to 25 parts by mass of distilled water and 0.75 parts by mass of Kaosera (registered trademark) 2020 as a dispersant, and mixed to obtain a uniform titanium oxide dispersion. .

  100 parts by weight of an acrylic-polyether polyurethane core-shell emulsion RIKA BOND (R) SU-P1885, 18.7 parts by weight of the above titanium oxide dispersion and 1.5 parts by weight of Carbodilite (R) V-02 were mixed. And 38 μm thick release-treated polyester film Purex A55, and dried in an oven at 100 ° C. for 5 minutes to obtain a 35 μm thick white ink receiving layer (C-4).

  100 parts by mass of an acrylic pressure-sensitive adhesive solution SK Dyne (registered trademark) 1310 and 0.7 parts by mass of an epoxy-based cross-linking agent E-5XM were mixed and applied on a 38 μm-thick release-treated polyester film Purex A55; It was dried in an oven at 100 ° C. for 5 minutes to obtain a transparent adhesive layer (D-2) having a thickness of 35 μm.

  The transparent adhesive layer (D-2) was laminated with the white ink receiving layer (C-4), and the release-treated polyester film for the white ink receiving layer was removed. The graphic image layer was printed on the white ink receiving layer (C-4) using an ink jet printer JV-33-130 (Mimaki Engineering Co., Ltd. (Tomi-shi, Nagano, Japan)). The polyurethane top layer (A) was laminated on the printed graphic image layer via the transparent adhesive layer (B) of Example 1 to obtain a graphic film of Example 4.

  The release-treated polyester film on the transparent adhesive layer (D-2) was removed from the obtained graphic film, and the graphic film was bonded to an aluminum plate (A1050P JIS H4000, 1.0 mm × 165.5 mm × 330.5 mm). A graphic film laminated plate was obtained.

  The surface of the graphic film laminated plate is embossed with the model of the vehicle number, and NSP-UP 401K-1 green ink (Hihiro Bix Co., Ltd. (Chiyoda-ku, Tokyo)) is coated only on the convex surface of the emboss by roll coating. After drying in an oven at 135 ° C. for 10 minutes, a license plate was obtained.

Comparative Example 1
162.50 parts by mass of JURYMER (registered trademark) YM-5 and 100.00 parts by mass of SK Dyne (registered trademark) 1506BHE were mixed, and 2.00 parts by mass of an epoxy crosslinking agent E-5XM was mixed therein. . The obtained liquid mixture was applied on a 38 μm thick release-treated polyester film Purex A55 and dried in an oven at 100 ° C. for 5 minutes to obtain an ink receiving layer (C-11) having a thickness of 30 μm. The white adhesive layer (D) of Example 1 was laminated with the ink receiving layer (C-11), and the release-treated polyester film for the ink receiving layer was removed. The graphic image layer was printed on the ink receiving layer (C-11) using an inkjet printing machine JV-33-130 (Mimaki Engineering Co., Ltd. (Tomi-shi, Nagano, Japan)). The polyurethane top layer (A) of Example 1 was laminated on the printed graphic image layer via the transparent adhesive layer (B) of Example 1 to obtain a graphic film of Comparative Example 1.

  The release-treated polyester film on the white adhesive layer (D) was removed from the obtained graphic film, and the graphic film was adhered to an aluminum plate (A1050P JIS H4000, 1.0 mm × 165.5 mm × 330.5 mm). A laminated plate was obtained.

  The surface of the graphic film laminated plate is embossed with the model of the vehicle number, and NSP-UP 401K-1 green ink (Hihiro Bix Co., Ltd. (Chiyoda-ku, Tokyo)) is coated only on the convex surface of the emboss by roll coating. After drying in an oven at 135 ° C. for 10 minutes, a license plate was obtained.

Comparative Example 2
100 parts by mass of Eternacoll (registered trademark) UW1005E and 11.5 parts by mass of Carbodite (registered trademark) V-02 were mixed, applied onto a 38-μm-thick release-treated polyester film Purex A55, and dried in an oven at 100 ° C. A graphic film, a graphic film laminated plate and a license plate were produced in the same manner as in Example 1, except that the ink receiving layer (C-12) having a thickness of 35 μm was obtained by drying for 35 minutes.

Comparative Example 3
SuperFlex® 650 was coated on a 38 μm thick release-treated polyester film Purex A55 and dried in a 100 ° C. oven for 5 minutes to give a 35 μm thick ink receiving layer (C-13). A graphic film, a graphic film laminated plate and a license plate were prepared in the same procedure as in 1.

Comparative Example 4
SuperFlex® 420 was coated on a 38 μm thick release-treated polyester film Purex A55 and dried in an oven at 100 ° C. for 5 minutes to obtain a 35 μm thick ink receiving layer (C-14). A graphic film, a graphic film laminated plate and a license plate were prepared in the same procedure as in 1.

Comparative Example 5
Instead of the polyurethane (PUR) top layer (A), a 50 μm thick polyvinyl chloride (PVC) top layer (A-15), and instead of the ink receiving layer (C-1), a 90 μm thick white polyvinyl chloride (PVC). Except for using the ink receiving layer (C-15), a graphic film, a graphic film laminated plate and a license plate were produced in the same procedure as in Example 1.

Dynamic viscoelasticity measurement of ink receiving layer The viscoelasticity of the ink receiving layer of the graphic film was measured using a dynamic viscoelasticity measuring device RSA-G2 (TA Instruments Japan Co., Ltd. (Shinagawa-ku, Tokyo, Japan)). In the tensile mode, at a frequency of 10.0 Hz, measurement was performed at a point every 12 seconds from a measurement start temperature of −60 ° C. to 200 ° C. at a rate of temperature increase of 5.0 ° C. per minute. The value of loss tangent (tan δ = loss modulus E ″ / storage modulus E ′) at −20 ° C. and the value of storage modulus E ′ at 25 ° C. were determined.

Printability of Ink Receiving Layer A graphic image layer was printed on the ink receiving layer of the graphic film using an ink jet printer JV-33-130 (Mimaki Engineering Co., Ltd. (Tomi, Nagano, Japan)). The appearance change of ink bleeding, bleeding, and color sharpness was visually confirmed. Those with no change in appearance were rated "OK" and those with confirmed change in appearance were rated "NG".

Adhesion The adhesion of the graphic film on the license plate to which the graphic film was attached was evaluated by a cross-cut test according to JIS K5600. Cuts were made at intervals of 1 mm in a grid pattern with five vertical and horizontal lines using a cutter, and Nichiban Cellotape (registered trademark) (Nichiban Co., Ltd. (Bunkyo-ku, Tokyo, Japan)) was stuck thereon and peeled off. A film with no peeling of the lattice-like film was rated "OK", and a film with peeling clearly observed and unusable was rated "NG".

Impact resistance The impact resistance of the license plate on which the graphic film was bonded was evaluated under the following evaluation conditions in accordance with JIS K5600-5-3 "weight drop resistance-DuPont formula". Samples with no film cracking were rated "OK" and those with film cracking were rated "NG".
Evaluation condition Diameter of the wick: 6.35 mm
Weight weight: 500gf
Drop height: 500mm
Test temperature: 25 ° C, 0 ° C and -20 ° C

  Table 2 shows the evaluation results.

  A graphic film containing an ink receiving layer having a tan δ at -20 ° C of 1.0 or more exhibited excellent impact resistance at low temperatures. The printability of the ink receiving layer containing the water-based polyurethane was poor, but the printability of the ink receiving layer containing the water-based acryl-polyurethane was good. The license plate of the embodiment can achieve polyvinyl chloride (PVC) free for green procurement in response to environmental issues.

DESCRIPTION OF SYMBOLS 10 Graphic film 20 Over laminate film 22 Top layer 24 Transparent adhesive layer 30 Receptor film 32 Graphic image layer 34 Ink receiving layer 36 Adhesive layer 40 Liner 50 Base plate 60 Graphic film laminated plate 62 Printing layer 70 Blank press die

Claims (11)

  An ink receiving layer containing water-based acrylic polyurethane core-shell emulsion particles.   The ink receiving layer according to claim 1, wherein a loss tangent tan δ of the ink receiving layer at -20 ° C. is 0.1 or more when a viscoelasticity is measured in a tensile mode at a frequency of 10.0 Hz. The storage modulus E ′ of the ink receiving layer at 25 ° C. when measured for viscoelasticity at a frequency of 10.0 Hz in a tensile mode is 1 × 10 ⁷ Pa or more, according to claim 1 or 2. Ink receiving layer.   4. The ink receiving layer according to claim 1, wherein the water-based acrylic polyurethane core-shell emulsion particles include at least one selected from the group consisting of polyether polyurethane, polyester polyurethane, and polycarbonate polyurethane. 5. Applying a composition containing an aqueous acrylic polyurethane core-shell emulsion to the surface to form a coating layer;
A method for producing an ink receiving layer, comprising drying or curing the coating layer.   A receptor film comprising the ink receiving layer according to claim 1 and an adhesive layer.   The receptor film according to claim 6, wherein at least one of the ink receiving layer and the adhesive layer is colored white.   A graphic film comprising the receptor film according to claim 6, a graphic image layer disposed on the ink receiving layer of the receptor film, and a top layer disposed on or above the receptor film. .   The graphic film according to claim 8, wherein the top layer is a transparent polyurethane layer.   A license plate comprising the graphic film according to claim 8 and a base plate. Providing a base plate;
Forming a graphic film laminated plate by applying the graphic film according to any one of claims 8 or 9 on or above the base plate,
Embossing or debossing the graphic film laminated plate,
A step of applying a printing layer to a convex portion or a concave portion of the embossed or debossed graphic film laminated plate,
And a method for manufacturing a license plate.

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