Wood grain decorative film

Abstract

The invention provides a wood grain decorative film which realizes a wood pattern like natural wood, and particularly presents the stereoscopic impression of wood. The wood grain decorative film according to the present invention comprises, in this order, a surface matte printing layer, a first thermoplastic resin film, a back surface printing layer comprising a wood grain printing part, and a second thermoplastic resin film, the surface matte printing layer being disposed so as to overlap the back surface printing layer and comprising a thin film printing part and a thick film printing part, the thick film printing part is configured in a manner of overlapping with the wooden printing part in a plan view and is thicker than the thin film printing part, and the matte ink weight of the thick film printing part is more than 3.0 g / m < 2 > than the matte ink weight of the thin film printing part.

Description

Technical Field

[0001] The present disclosure relates to a wood grain decorative film. Background Art

[0002] Various methods of presenting an appearance like natural wood have been studied for wood grain decorative films that are attached to a substrate to give a wood grain design. For example, Patent Document 1 discloses a wood-decorating sheet material having: a transparent resin film having two main surfaces; a wood grain pattern portion provided on the first main surface of the transparent resin film; a colored base film layer laminated on the wood grain pattern portion on the first main surface of the transparent resin film; and a duct pattern portion provided on the second main surface of the transparent resin film, wherein the wood-decorating sheet material is characterized in that the duct pattern portion is formed by printing ink containing matte beads, the duct pattern portion is embedded in the surface of the transparent resin film, but its surface is exposed.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2001-260299 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In order to present the wood texture of natural wood in a wood grain decorative film, the inventors have also studied to present a three-dimensional effect by embossing the surface of the decorative film. However, there is room for further research to present a more three-dimensional wood texture.

[0008] The present invention has been made in view of the above-mentioned current situation, and an object of the present invention is to provide a wood grain decorative film that realizes a wood grain pattern like natural wood, and in particular, exhibits a three-dimensional effect of wood grain.

[0009] Technical means of solving problems

[0010] (1) One embodiment of the present invention is a wood grain decorative film, which includes a surface matte printing layer, a first thermoplastic resin film, a back printing layer including a wood grain printing portion, and a second thermoplastic resin film in sequence, wherein the surface matte printing layer is arranged in an overlapping manner with the back printing layer, and includes a thin film printing portion and a thick film printing portion, wherein the thick film printing portion is arranged in an overlapping manner with the wood grain printing portion when viewed from above and is thicker than the thin film printing portion, and the matte ink weight of the thick film printing portion is 3.0 g / m greater than the matte ink weight of the thin film printing portion 2 above.

[0011] (2) An embodiment of the present invention is a wood grain decorative film. Based on the structure of (1), the weight of the matte ink of the film printing part is 2.65 g / m 2 above.

[0012] (3) An embodiment of the present invention is a wood grain decorative film, wherein, based on the structure of (1) or (2), the surface matte printed layer contains silicon oxide.

[0013] (4) One embodiment of the present invention is a wood grain decorative film, wherein in addition to any one of the structures (1) to (3) above, the first thermoplastic resin film is a polyvinyl chloride film.

[0014] (5) One embodiment of the present invention is a wood grain decorative film, wherein in addition to any one of the structures (1) to (4) above, the second thermoplastic resin film is a polyvinyl chloride film.

[0015] (6) One embodiment of the present invention is a wood grain decorative film, wherein in addition to any one of the structures (1) to (5) above, the second thermoplastic resin film is colored.

[0016] (7) One embodiment of the present invention is a wood grain decorative film, wherein in addition to any one of the structures (1) to (6), the surface of the matte surface print layer on the side opposite to the second thermoplastic resin film has an embossed shape.

[0017] (8) One embodiment of the present invention is a wood grain decorative film having any one of the structures (1) to (7) above, further comprising an adhesive layer on the side of the second thermoplastic resin film opposite to the back printed layer.

[0018] Effects of the Invention

[0019] According to the present invention, it is possible to provide a wood grain decorative film that realizes a wood grain pattern like natural wood, and in particular, exhibits a three-dimensional effect of wood grain. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] [ Figure 1 ] is a cross-sectional schematic diagram showing an example of a wood grain decorative film according to an embodiment.

[0021] [ Figure 2 ]yes Figure 1 A perspective view of the wood grain decorative film shown.

[0022] [ Figure 3 ]yes Figure 1 A schematic plan view of a matte surface printed layer is shown.

[0023] [ Figure 4 ]yes Figure 1 A plan view of the back printing layer is shown.

[0024] [ Figure 5 ] is a schematic cross-sectional view showing an example of a wood grain decorative film subjected to embossing.

[0025] [ Figure 6 ]yes Figure 5 A perspective view of the wood grain decorative film shown.

[0026] [ Figure 7 ] is a plan view schematically showing an example of an embossed shape imitating wood fibers.

[0027] [ Figure 8 ] is a plan photograph of the wood grain decorative film of Example 3.

[0028] [ Fig. 9 ] is a photograph of the wood grain decorative film of Example 3 taken from the tilt direction. DETAILED DESCRIPTION

[0029] Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings by way of example only, but the present invention is not limited to these embodiments. In addition, the structures of the various embodiments may be appropriately combined and modified within the scope of the gist of the present invention.

[0030] Figure 1 It is a cross-sectional schematic diagram showing an example of the wood grain decorative film according to the embodiment. Figure 2 yes Figure 1 The three-dimensional image of the wood grain decorative film shown in FIG. Figure 1 and Figure 2 As shown, the wood grain decorative film 100 of the embodiment includes a matte surface printed layer 10, a first thermoplastic resin film 20, a back printed layer 30 and a second thermoplastic resin film 40 in order. When used, the matte surface printed layer 10 becomes the viewer side (surface side).

[0031] (Matte printing layer on the surface)

[0032] Figure 3 yes Figure 1 The schematic diagram of the matte printed layer on the surface is shown in FIG. Figure 1 to Figure 3 As shown, the matte surface printing layer 10 includes a thin film printing part 11 and a thick film printing part 12. In addition, the matte surface printing layer 10 is arranged in a manner overlapping with the back printing layer. By arranging the matte surface printing layer 10 in a manner overlapping with the back printing layer 30, the glossiness of the entire wood grain decorative film 100 can be suppressed.

[0033] The matte surface printed layer 10 preferably overlaps not only the wood grain printed portion 31 of the back printed layer 30 described later but also overlaps at least a portion of the portion 32 other than the wood grain printed portion when viewed from above, and is more preferably arranged to overlap the entire surface of the back printed layer 30. In addition, even when the matte surface printed layer 10 is arranged to overlap the entire surface of the back printed layer 30, the matte surface printed layer may not be arranged in a portion that is not visible to an observer when a wood grain decorative film is used (such as an end portion of the wood grain decorative film). In this specification, the state of viewing from the observer side, which becomes the surface side when a wood grain decorative film is used, is referred to as a top view.

[0034] The matte surface printing layer 10 preferably contains a matting agent. By containing a matting agent, the glossiness of the matte surface printing layer 10 can be reduced. The matte surface printing layer 10 is more preferably formed of a matte ink containing a matte agent. The thickness of the thin film printing part 11 and the thick film printing part 12 can be adjusted by the weight of the matte ink. The greater the weight of the matte ink, the thicker the thickness of the matte surface printing layer 10 is, and the lower the glossiness is.

[0035] The thick film printed portion 12 is thicker than the thin film printed portion 11, and is arranged so as to overlap with the wood texture printed portion 31 when viewed from above. Since the thick film printed portion 12 is thicker than the thin film printed portion 11, its glossiness is lower than that of the thin film printed portion 11. On the oblique grain surface or straight grain surface of natural wood, ducts and the like appear as concave portions, so by overlapping the thick film printed portion 12 on the wood texture printed portion 31 and lowering the glossiness, the wood texture printed portion 31 can be made to look concave.

[0036] By arranging the thick film printing part 12 and the wood texture printing part 31 so as to overlap when viewed from above, the thick film printing part 12 and the wood texture printing part 31 can be synchronized to present a more realistic wood texture pattern. The thick film printing part 12 only needs to overlap at least a portion of the wood texture printing part 31 when viewed from above, but it is preferred that the area where the thick film printing part 12 overlaps with the wood texture printing part 31 is large. On the other hand, the thick film printing part 12 is preferably not exposed from the wood texture printing part 31 when viewed from above, such as Figure 3 and the following Figure 4 As shown, it is further preferred that the thick film printed portion 12 and the wood texture printed portion 31 have the same shape in a plan view. The thick film printed portion 12 may include a plurality of straight or curved line patterns extending in substantially the same direction, similarly to the wood texture printed portion 31.

[0037] The matte ink weight of the thick film printing part 12 is 3.0 g / m2 more than that of the thin film printing part 11. 2By setting the matte ink weight of the thick film printing part 12 to the above range, the wood texture printing part 31 can be made to look concave, and the part 32 outside the wood texture printing part can be made to look protruding, thereby presenting a three-dimensional effect. When the difference between the matte ink weight of the thick film printing part 12 and the matte ink weight of the thin film printing part 11 (hereinafter also referred to as "matte ink weight difference") is less than 3.0 g / m 2 The matte ink weight difference is preferably 3.52 g / m 2 More preferably 5.0 g / m 2 The upper limit of the matte ink weight of the thick film printing part 12 is 3.0 g / m greater than the matte ink weight of the thin film printing part 11. 2 The above is not particularly limited, but when the surface matte printing layer 10 is produced by gravure printing, if the amount of matte ink that can be retained on the gravure printing plate is taken into consideration, it is, for example, 23 g / m 2 In this case, the upper limit of the matte ink weight difference is less than 23g / m 2 In this specification, "matte ink weight" refers to the weight of the matte ink after drying. The drying conditions of the matte ink are 60°C and 1 minute.

[0038] The matte ink weight of the film printing unit 11 may be, for example, 0.1 g / m 2 The preferred lower limit of the matte ink weight of the film printing unit 11 is 0.5 g / m 2 The more preferred lower limit is 0.9 g / m 2 The preferred lower limit is 2.0 g / m 2 From the viewpoint of obtaining the three-dimensional effect of wood texture while suppressing the overall glossiness of the wood grain decorative film 100, thereby presenting a more natural wood-like feel, it is particularly preferred that the matte ink weight difference be 3.0 g / m 2 The above, and the matte ink weight of the film printing part 11 is 2.65g / m 2 From the perspective of suppressing the overall glossiness of the wood grain decorative film 100, the upper limit of the matte ink weight of the thin film printing part 11 is not particularly limited, and the difference between the matte ink weight of the thick film printing part 12 and the matte ink weight of the thin film printing part 11 is as long as it is 3.0 g / m 2 That’s all.

[0039] Examples of the matting agent include inorganic fillers such as silicon oxide (silicon dioxide) and calcium carbonate, and resin beads such as acrylic resins and urethane resins. Inorganic fillers are more suitable as matting agents used in this embodiment than resin beads due to their high stability. Among inorganic fillers, silicon oxide is preferred as a matting agent from the perspective of high matting effect.

[0040] The matte surface printing layer 10 may also contain silicon oxide. The content of silicon oxide contained in the matte ink is, for example, 18% to 53% by mass relative to the entire matte ink. The matte ink may also contain a binder resin. Examples of the binder resin include acrylic resins, urethane resins, and the like.

[0041] The matte surface printed layer 10 may or may not contain a colorant. However, since a colorant may absorb heat, it may not contain a colorant from the viewpoint of heat resistance.

[0042] (First Thermoplastic Resin Film)

[0043] The first thermoplastic resin film 20 functions as a printing base for the back printed layer 30 and the front matte printed layer 10. Preferably, the back printed layer 30 and the front matte printed layer 10 are printed on both sides of the first thermoplastic resin film 20.

[0044] The first thermoplastic resin film 20 is preferably a transparent film so that the back printed layer 30 can be seen when viewed from the observer's side. The total light transmittance of the transparent film is preferably 80% or more, more preferably 90% or more. In addition, in this specification, the total light transmittance is a value obtained based on Japanese Industrial Standards (JIS) K 7375.

[0045] The first thermoplastic resin film 20 contains a thermoplastic resin. Examples of the thermoplastic resin include polyolefins such as polyethylene or polypropylene, polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), acrylonitrile / butadiene / styrene copolymer (ABS resin), and polycarbonate. Among them, the first thermoplastic resin film 20 is preferably a polyvinyl chloride film in terms of good elongation, difficulty in breaking, and ability to maintain an embossed shape during molding. The polyvinyl chloride film may also contain polyvinyl chloride and a plasticizer.

[0046] As the polyvinyl chloride, for example, homopolymers of vinyl chloride, other monomers copolymerizable with vinyl chloride, and copolymers of vinyl chloride can be cited. As the other monomers copolymerizable, for example, vinyl esters such as vinyl acetate and vinyl propionate; olefins such as ethylene, propylene, and styrene; (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, and methyl (meth)acrylate; maleic acid diesters such as dibutyl maleate and diethyl maleate; fumaric acid diesters such as dibutyl fumarate and diethyl fumarate; acrylonitrile (acrylonitrile) and methacrylonitrile (vinylcyanide); vinyl halides such as vinylidene chloride and vinyl bromide; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, etc. These can be used alone or in combination of two or more. In addition, in this specification, the so-called "(meth)acrylic acid" means "at least one of acrylic acid and methacrylic acid".

[0047] The content of the other copolymerizable monomer in the copolymer is usually 50% by mass or less, preferably 10% by mass or less. Among the polyvinyl chlorides, homopolymers of vinyl chloride are preferred in terms of excellent dimensional stability.

[0048] The average degree of polymerization of the polyvinyl chloride is preferably 700 to 1300, more preferably 700 to 1000. In the present invention, the average degree of polymerization of polyvinyl chloride refers to the average degree of polymerization measured in accordance with JIS K 6721 "Testing methods for vinyl chloride resins". If the average degree of polymerization exceeds 1300, the elongation of the polyvinyl chloride film may become insufficient.

[0049] The polyvinyl chloride may include straight PVC or cross-linked PVC. By including cross-linked PVC, heat resistance and solvent resistance can be improved.

[0050] The cross-linked PVC may be blended in an amount of 0 to 50 parts by mass relative to 100 parts by mass of the total of the pure PVC and the cross-linked PVC. If the content of the cross-linked PVC is 0 to 50 parts by mass relative to 100 parts by mass of the total of the pure PVC and the cross-linked PVC, heat resistance and solvent resistance may be improved while maintaining processability.

[0051] Examples of the pure PVC include "Kanevinyl S1008N" (average degree of polymerization: 800), "Kanevinyl S1007" (average degree of polymerization: 700), "Kanevinyl S1008" (average degree of polymerization: 800), "Kanevinyl S1001" (average degree of polymerization: 1050), "Kanevinyl S1001N" (average degree of polymerization: 1050), "Kanevinyl S1003" (average degree of polymerization: 1300), and "Kanevinyl S1003N" (average degree of polymerization: 1300), all manufactured by Kaneka Chemical Co., Ltd.

[0052] Examples of the cross-linked PVC include "Kanevinyl K07S" (average degree of polymerization: 720), "Kanevinyl K10S" (average degree of polymerization: 1030), "Kanevinyl K10M" (average degree of polymerization: 1080), "Kanevinyl K13S" (average degree of polymerization: 1290), and "Kanevinyl K13M" (average degree of polymerization: 1100) manufactured by Kaneka Chemical Co., Ltd.

[0053] The plasticizer is an additive that imparts flexibility to the polyvinyl chloride film. The plasticizer is not particularly limited, and examples thereof include phthalates such as di-2-ethylhexyl phthalate (dioctyl phthalate (DOP)), dibutyl phthalate, dinonyl phthalate, diisononyl phthalate (DINP), bis(2-ethylhexyl) terephthalate (dioctylterephthalate (DOTP)), adipic acid esters, polyesters formed by bonding adipic acid and polyols, and the like.

[0054] The content of the plasticizer is preferably 8 parts by mass or more and 30 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride. In the case of printing the back printing layer 30 and the surface matte printing layer 10 on both sides of the first thermoplastic resin film 20, the first thermoplastic resin film 20 preferably has a printing resistance that suppresses swelling caused by the solvent contained in the ink used in the back printing layer 30 and the surface matte printing layer 10. By making the content of the plasticizer within the range, the first thermoplastic resin film 20 is not easy to absorb the solvent contained in the ink, so that the strength of the film can be ensured, and thus the printing resistance can be improved. In addition, when printing and drying the ink, the elongation of the film can be suppressed and the positional displacement of the back printing layer and / or the surface matte printing layer can be suppressed. If the content of the plasticizer is less than 8 parts by mass, the film may be broken or torn during calendering. If the content of the plasticizer exceeds 30 parts by mass, when printing the back printing layer or the surface matte printing layer, the elongation of the film may occur and the printing process becomes difficult. The content of the plasticizer is more preferably 10 parts by mass or more and 20 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride.

[0055] The first thermoplastic resin film 20 may use substances commonly formulated in polyvinyl chloride as additives, and may also contain stabilizers, ultraviolet absorbers, processing aids, antibacterial agents, and the like.

[0056] Halogen-containing resins such as polyvinyl chloride are prone to thermal decomposition due to dehydrohalogenation during melt kneading or film formation, so stabilizers are sometimes added to suppress deterioration during the processing process. Examples of the stabilizer include phosphite-based antioxidants, heat stabilizers containing magnesium, aluminum, etc., Ba-Zn-based stabilizers, and organic stabilizers containing β-diketone compounds.

[0057] The thickness of the first thermoplastic resin film 20 is preferably 50 μm or more and 300 μm or less. If it is within the above range, the strength and durability of the film itself can be obtained, and it can be easily attached to the substrate because it has appropriate toughness. The thickness of the first thermoplastic resin film 20 is more preferably 70 μm or more and 250 μm or less. Considering that the back printing layer 30 and the surface matte printing layer 10 are printed on both sides of the first thermoplastic resin film 20, the thickness of the first thermoplastic resin film 20 can be thicker than the thickness of the second thermoplastic resin film 40 described later.

[0058] (Back printing layer)

[0059] Figure 4 yes Figure 1 The schematic plan view of the back printing layer is shown in FIG. Figure 4As shown, the back printing layer 30 includes a wood texture printing part 31. The wood texture printing part 31 is a pattern that imitates the wood texture pattern of natural wood. The wood texture pattern may also include the ducts, nodes, radial fibers, latewood parts, etc. that appear in the cross section (straight grain surface or wood texture surface) in the fiber direction of natural wood, and the color appears darker than the surrounding (appears concave). The wood texture printing part 31 is preferably a linear pattern including a plurality of straight lines or curves extending in substantially the same direction.

[0060] The wood texture pattern only needs to include at least the wood texture printed portion 31, and may include a portion other than the wood texture printed portion 32. The portion other than the wood texture printed portion 32 may be, for example, a portion corresponding to the early wood of natural wood.

[0061] The texture printed portion 31 preferably looks recessed compared to the portion 32 other than the texture printed portion, and therefore the texture printed portion 31 is preferably printed in a color with a lower brightness than the portion 32 other than the texture printed portion. The portion 32 other than the texture printed portion may be printed or may not be printed.

[0062] Since the wood grain decorative film presents the three-dimensional effect of wood grain by overlapping the thick film printing part 12 and the wood grain printing part 31, when both the wood grain printing part 31 and the part 32 other than the wood grain printing part are printed, the ink weight of the wood grain printing part 31 and the ink weight of the part 32 other than the wood grain printing part are not particularly limited and can be the same. If the ink weight of the wood grain printing part 31 is greater than the ink weight of the part 32 other than the wood grain printing part, the wood grain can be made to look more three-dimensional. In this specification, "ink weight" refers to the weight of the ink after drying. The drying conditions of the ink are 60°C and 1 minute.

[0063] (Second Thermoplastic Resin Film)

[0064] The second thermoplastic resin film 40 is disposed on the back side (the side opposite to the viewer's side) of the matte surface printed layer 10 , the first thermoplastic resin film 20 and the back printed layer 30 , and functions as a base film for supporting the wood grain decorative film 100 .

[0065] The second thermoplastic resin film 40 may have the same or different compositions as the first thermoplastic resin film 20. The second thermoplastic resin film 40 may be a polyvinyl chloride film, and the polyvinyl chloride contained in the second thermoplastic resin film 40 may be the same or different in composition and average molecular weight from the polyvinyl chloride contained in the first thermoplastic resin film 20. In addition, the stabilizer, ultraviolet absorber, processing aid, antibacterial agent, etc. exemplified in the first thermoplastic resin film 20 may also be contained.

[0066] The polyvinyl chloride film may also contain a plasticizer. The content of the plasticizer contained in the second thermoplastic resin film 40 does not need to take into account the printing resistance as in the first thermoplastic resin film 20, but from the perspective of suppressing deformation after lamination of the first thermoplastic resin film 20 and the second thermoplastic resin film 40, it is preferred that the hardness of the film (the content of the plasticizer) is equal.

[0067] The content of the plasticizer contained in the second thermoplastic resin film 40 is preferably 8 parts by mass or more and 30 parts by mass or less, and more preferably 10 parts by mass or more and 20 parts by mass or less, based on 100 parts by mass of the polyvinyl chloride.

[0068] The thickness of the second thermoplastic resin film 40 is preferably 50 μm or more and 300 μm or less. Within this range, the strength and durability of the film itself can be obtained, and it is easy to adhere to the substrate because of its moderate toughness. The thickness of the second thermoplastic resin film 40 is more preferably 70 μm or more and 250 μm or less.

[0069] The second thermoplastic resin film 40 may be colored. For example, it may be colored brown. The colorant contained in the second thermoplastic resin film 40 is not particularly limited, and dyes and pigments commonly used in the field of vinyl chloride films may be used.

[0070] (Embossed shape)

[0071] Figure 5 This is a schematic cross-sectional view showing an example of an embossed wood-grain decorative film. Figure 6 yes Figure 5 The embossed shape 70 may be provided on the surface of the matte surface printed layer 10 on the side opposite to the first thermoplastic resin film 20. By providing the embossed shape 70, the wood grain decorative film 100 may be given a touch like natural wood.

[0072] Since the wood grain decorative film 100 of the embodiment presents a three-dimensional sense of wood grain through the thick film printing part 12 of the surface matte printing layer 10, Figure 5 and Figure 6 As shown, the embossed shape 70 may not be synchronized with the planar shape of the wood texture printing part 31 or the thick film printing part 12. The embossed shape 70 may be a pear skin pattern or a pattern imitating wood fiber.

[0073] Figure 7 : is a schematic plan view showing an example of an embossed shape imitating wood fiber. The embossed shape 70 imitating wood fiber may also be provided with a plurality of linear recesses, and the plurality of linear recesses are preferably arranged along the extension direction of the wood texture printed portion 31 of the back printed layer. The embossed shape 70 imitating wood fiber preferably exposes fibers thinner than the wood texture pattern of the wood texture printed portion 31.

[0074] The arithmetic mean roughness Ra of the surface of the wood grain decorative film 100 with an embossed shape can be, for example, 7μm to 30μm, the ten-point average roughness Rz can be, for example, 20μm to 60μm, and the maximum height Ry can be, for example, 30μm to 100μm. The Ra, Rz, and Ry are all values ​​measured by a method based on JIS B0601-1994. The height of the concave and convex of the embossed shape can also be greater than the thickness of the thick film printing part 12. The thickness of the thick film printing part 12 that can be achieved using matte ink is about 1 / 100 of the height of the surface concave and convex of the wood grain decorative film 100 given by the embossed shape. Since the concave and convex of the embossed shape are sufficiently larger than the thickness of the thick film printing part 12, the thickness of the thick film printing part 12 has little influence on the calculation of the Ra, Rz, and Ry.

[0075] The embossed shape 70 can be formed by pressing an embossing roller having a desired pattern formed on the surface against the surface of the matte surface printed layer 10 on the side opposite to the first thermoplastic resin film 20 .

[0076] (adhesive layer)

[0077] like Figure 1 and Figure 2 As shown, the wood grain decorative film 100 may include an adhesive layer 50 on the side of the second thermoplastic resin film 40 opposite to the back printed layer 30. The thickness of the adhesive layer 50 is not particularly limited, but is preferably 10 μm to 60 μm, and more preferably 20 μm to 50 μm.

[0078] The adhesive layer 50 is not particularly limited as long as it has an adhesive function, and examples thereof include adhesive layers containing adhesives such as acrylic adhesives, rubber adhesives, and silicone adhesives. Among them, acrylic adhesives are preferably used in terms of excellent adhesiveness, processability, and heat resistance, and being relatively inexpensive.

[0079] The wood grain decorative film 100 may also be provided with a spacer 60 on the side of the adhesive layer 50 opposite to the second thermoplastic resin film 40. The spacer 60 is not particularly limited as long as it protects the surface of the adhesive layer 50 and is removable during use, and any spacer commonly used in the field of decorative films may be used.

[0080] Although not shown, the wood grain decorative film 100 may have a primer layer between the second thermoplastic resin film 40 and the adhesive layer 50. In addition, a metal film may be provided between the back printed layer 30 and the second thermoplastic resin film 40. Examples of the metal film include vapor-deposited films of metals such as aluminum and indium. The thickness of the metal film is, for example, 1 μm or less.

[0081] The wood grain decorative film 100 of the embodiment can be attached to the surface of a substrate to give a wood grain design. As the substrate, there can be cited decorative panels (wall decoration materials) installed on the wall surface, interior doors, closet or kitchen doors, furniture, floors and other interior materials. The material of the substrate is not particularly limited, for example, there can be cited: polycarbonate resin, acrylic resin, styrene resin and other resins, acrylonitrile-butadiene-styrene copolymer (ABS resin); metals such as iron, copper, aluminum; alloys, etc.

[0082] (Manufacturing method)

[0083] The wood grain decorative film of the embodiment can be manufactured, for example, by the following method. Another embodiment of the present invention can be a method for manufacturing a wood grain decorative film, comprising: a process of printing a back printed layer including a wood grain printed portion on a first surface of a first thermoplastic resin film, and printing a surface matte printed layer on a second surface of the first thermoplastic resin film on the side opposite to the first surface; and a process of laminating a second thermoplastic resin film on the surface of the back printed layer on the side opposite to the first thermoplastic resin film, the surface matte printed layer including a thin film printed portion and a thick film printed portion thicker than the thin film printed portion and overlapping with the back printed layer when viewed from above, the thick film printed portion being formed to overlap with the wood grain printed portion when viewed from above, and the matte ink weight of the thick film printed portion being 3.0 g / m greater than the matte ink weight of the thin film printed portion. 2 above.

[0084] As the film forming method of the first thermoplastic resin film 20 and the second thermoplastic resin film, conventionally known forming methods such as calendering, extrusion, and injection molding can be used, but calendering is preferred in that even a thin film can be produced with excellent thickness accuracy. The calendering form used in the calendering process is not particularly limited, and conventionally known forms such as inverted L-shaped, Z-shaped, upright two-root type, L-shaped, and inclined three-root type can be used.

[0085] In the process of printing the back printed layer and the surface matte printed layer, the back printed layer including the wood texture printed portion is printed on the first surface of the first thermoplastic resin film, and the surface matte printed layer is printed on the second surface of the first thermoplastic resin film. That is, the back printed layer and the surface matte printed layer are printed on both sides of the first thermoplastic resin film. By printing the back printed layer and the surface matte printed layer on both sides of the first thermoplastic resin film, the wood texture printed portion and the thick film printed portion can be synchronized, and the wood texture printed portion can be made to appear recessed relative to the surrounding area. The surface matte printed layer is printed in a manner overlapping with the back printed layer, and the thick film printed portion is formed to overlap with the wood texture printed portion when viewed from above.

[0086] The process of printing the back printing layer and the surface matte printing layer can be carried out by inkjet printing, gravure printing, screen printing, rotary screen printing, flexographic printing, lithographic printing, electrostatic printing, etc., preferably gravure printing. In particular, the surface matte printing layer is preferably printed by gravure printing. The reason is that double-sided printing can be performed, and the surface of the gravure printing plate is smooth, and the ink adhesion is good when printing on a vinyl chloride film. Below, an example of forming a back printing layer and a surface matte printing layer by gravure printing is described. Gravure printing is a printing method in which ink is filled into the concave part of the gravure printing plate with concave and convex corresponding to the printed pattern on the surface, and the ink is transferred to the film.

[0087] The step of printing the back printed layer and the surface matte printed layer may also include: a step of printing the back printed layer on the first surface of the first thermoplastic resin film; and a step of printing the surface matte printed layer on the second surface of the first thermoplastic resin film. When the printing of the back printed layer and the printing of the surface matte printed layer are performed in different steps, the order of printing the back printed layer and the surface matte printed layer is not particularly limited.

[0088] The following describes the case where the matte surface printing layer is printed after the back printing layer is printed. For example, the first thermoplastic resin film is sandwiched between the gravure printing plate and the impression cylinder, the gravure printing plate and the impression cylinder are rotated, and the ink for wood texture printing filled in the gravure printing plate is transferred to the first surface of the first thermoplastic resin film, thereby printing the wood texture pattern. The gravure printing plate may also be cylindrical.

[0089] Thereafter, the first thermoplastic resin film is turned over, and the first thermoplastic resin film is clamped between the gravure printing plate and the impression cylinder, and the gravure printing plate and the impression cylinder are rotated to transfer the matte ink filled in the gravure printing plate to the second surface of the first thermoplastic resin film, thereby printing a surface matte printing layer including a thin film printing part and a thick film printing part.

[0090] The matte surface printing layer includes a thin film printing portion and a thick film printing portion which is thicker than the thin film printing portion and overlaps with the back printing layer in a plan view.

[0091] The matte ink weight of the thick film printing part is 3.0g / m2 more than that of the thin film printing part. 2 By adjusting the depth of the concavo-convex formed on the surface of the gravure printing plate, the matte ink weight of the thin film printing part and the thick film printing part can be adjusted. For example, the thin film printing part can be formed by using the deepest groove (concave part) on the surface of the gravure printing plate as the thick film printing part and shallowing the depth of the groove based on the thick film printing part.

[0092] The difference between the matte ink weight of the thick film printing part and the matte ink weight of the thin film printing part (matte ink weight difference) is preferably 3.52 g / m 2 More preferably 5.0 g / m 2 The upper limit of the matte ink weight of the thick film printing part is, for example, 23 g / m 2 .

[0093] The matte ink weight of the film printing part can be, for example, 0.1 g / m 2 The preferred lower limit of the matte ink weight of the film printing part is 0.5 g / m 2 The more preferred lower limit is 0.9 g / m 2 The preferred lower limit is 2.0 g / m 2 In this case, the upper limit of the matte ink weight difference is less than 23g / m 2 It is particularly preferred that the matte ink weight difference is 3.0 g / m 2 Above, and the matte ink weight of the film printing part is 2.65g / m 2 above.

[0094] The first thermoplastic resin film and the second thermoplastic resin film can be heat-laminated by being pressed, for example, between a pair of rollers heated to a predetermined temperature. By using a pair of embossing rollers in the heat lamination, the first thermoplastic resin film and the second thermoplastic resin film can be heat-laminated while embossing the surface of the matte surface printed layer on the viewer side. When a pair of embossing rollers are used in the heat lamination, not only the surface of the matte surface printed layer on the viewer side is embossed, but also the surface of the back side of the second thermoplastic resin film is embossed.

[0095] Thereafter, the adhesive layer formed on the spacer may be laminated on the side of the second thermoplastic resin film opposite to the back printed layer.

[0096] Example

[0097] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0098] The following Table 1 shows the arithmetic mean roughness Ra, ten-point average roughness Rz and maximum height Ry of the embossing rollers used in the examples and comparative examples. Ra, Rz and Ry were measured by a surface roughness measuring machine according to JIS B 0601-1994 under the following conditions. Ra, Rz and Ry in Table 1 are the average values ​​after three measurements. Embossing 1 and Embossing 2 are embossing rollers with pear skin patterns.

[0099] Measuring device: "Surftest SJ-310" manufactured by Mitutoyo

[0100] Cut-off value λc: 0.8mm

[0101] Number of intervals (the number of intervals to be measured in the measurement length): 5

[0102] [Table 1]

[0103]

[0104] (Example 1)

[0105] As polyvinyl chloride, 70 parts by mass of pure PVC "Kanevinyl S1008N" (average degree of polymerization: 800) manufactured by Kaneka Chemical Co., Ltd. and 30 parts by mass of cross-linked PVC "Kanevinyl K07S" (average degree of polymerization: 720) manufactured by Kaneka Chemical Co., Ltd. were mixed to obtain polyvinyl chloride. With respect to a total of 100 parts by mass of the polyvinyl chloride, 6 parts by mass of diisononyl phthalate (DINP) and 4 parts by mass of epoxidized soybean oil ("Adekasizer O-130P" manufactured by ADEKA) were blended as plasticizers.

[0106] In addition, 0.7 parts by mass of a phosphite antioxidant ("Adekastab 1500" manufactured by ADEKA) and 4.0 parts by mass of a Ba-Zn stabilizer ("Adekastab AC-258" manufactured by ADEKA) were added as stabilizers to a total of 100 parts by mass of the polyvinyl chloride. Furthermore, 1.5 parts by mass of an acrylic processing aid ("Metablen P-551A" manufactured by Mitsubishi Chemical Corporation) and 1.0 parts by mass of an ultraviolet absorber ("Adekastab 1413" manufactured by ADEKA) were added to a total of 100 parts by mass of the polyvinyl chloride to obtain a polyvinyl chloride resin composition.

[0107] The polyvinyl chloride resin composition was calendared to produce a transparent polyvinyl chloride film having a thickness of 80 μm and a total light transmittance of 90% as a first thermoplastic resin film.

[0108] After adding a colorant to the polyvinyl chloride resin composition, the composition was calendered to produce a colored polyvinyl chloride film having a thickness of 70 μm as a second thermoplastic resin film.

[0109] On one side of the first thermoplastic resin film, a texture pattern including a texture printing portion is printed by gravure printing as a backside printing layer.

[0110] Thereafter, the first thermoplastic resin film was turned over and a matte printed layer was printed on both sides of the film using matte ink by gravure printing. The matte ink was dried at 60° C. for 1 minute.

[0111] As the gravure printing plate, a printing plate having the same pattern as the wood texture printing part is used. The matte ink layer is printed in such a manner that the thick film printing part overlaps the wood texture printing part, and the thin film printing part overlaps the part other than the wood texture printing part. In the case where the depth of the concave part formed in the gravure printing plate is represented by 12 levels, the deepest scale 12 is set as the thick film printing part. In Example 1, a gravure printing plate with a thin film printing part of scale 9 is used to print the surface matte printing layer.

[0112] As the matte ink, an acrylic urethane-based matte ink containing an acrylic urethane-based resin as a binder resin and silicon oxide (silicon dioxide) as a matting agent is used. The content of silicon oxide relative to the entire matte ink is 18% to 53% by mass.

[0113] After double-sided printing, the second thermoplastic resin film was overlapped on the surface of the first thermoplastic resin film on which the back printed layer was printed, and heat laminated by passing between a pair of embossing rollers engraved with a wood fiber pattern. In Example 1, the embossing roller "Embossed 1" shown in Table 1 was used.

[0114] A 40 μm thick adhesive layer was formed using an acrylic adhesive with a release paper having a thickness of 120 μm as a spacer. Thereafter, the adhesive layer was attached to the surface of the second thermoplastic resin film on the side opposite to the back printed layer to produce the wood grain decorative film of Example 1. The wood grain decorative film of Example 1 has a surface matte printed layer, a first thermoplastic resin film, a back printed layer, a second thermoplastic resin film, an adhesive layer and a release paper in order from the surface side, and has an embossed shape on the surface of the surface matte printed layer side.

[0115] (Examples 2 to 18, Comparative Examples 1 to 4)

[0116] The wood grain decorative films of Examples 2 to 18 and Comparative Examples 1 to 4 were prepared in the same manner as in Example 1, except that the scale of the film printing portion of the gravure printing plate used for printing the surface matte printing layer and the type of the embossing roller for thermally laminating the first thermoplastic resin film and the second thermoplastic resin film are shown in Table 3.

[0117] <Calculation of Matte Ink Weight>

[0118] The relationship between the depth (scale) of the gravure printing plate used for printing the matte surface printing layer in the examples and comparative examples and the matte ink weight of the matte surface printing layer in the wood grain decorative film was studied by the following method.

[0119] Twelve gravure printing plates with a depth of 1 to 12 levels were prepared, and samples with a surface matte printing layer of uniform thickness printed on the entire surface were prepared using each gravure printing plate. The matte ink used was the same as that in Example 1, and after coating, it was dried at 60° C. for 1 minute. The structure of each sample other than the surface matte printing layer was the same as that in Example 1.

[0120] A portion of the matte surface printed layer of each sample was wiped with alcohol, and a test piece was prepared by cutting out the portion where the matte surface printed layer was removed and the portion where the matte surface printed layer was not removed with the same area. The matte ink weight was calculated for each scale based on the weight difference between the test piece where the matte surface printed layer was removed and the test piece where the matte surface printed layer was not removed.

[0121] The method of cutting out the test piece is not particularly limited as long as the test piece of the same area can be produced. In this study, a punching punch was used. As a punching punch, a rotary punching pliers (product number: 9070-220) of KNIPEX Co., Ltd. was used to produce a circular sample with a diameter of 5 mm. The sample was subjected to a temperature of 30°C, a humidity of 60%, and a pressure of 717 kN / m 2 In addition, for one measurement, 79 test pieces from which the surface matte printed layer was removed and 79 test pieces from which the surface matte printed layer was not removed were prepared. For each sample, the average value of the three measurements is shown in Table 2 below.

[0122] The solvent for wiping the matte printed layer on the surface can be appropriately selected according to the type of matte ink. In this study, isopropyl alcohol (IPA) was used. Regarding wiping the matte printed layer on the surface, a cotton cloth soaked in IPA was used at 9.8 kN / m 2 The sample was rubbed 50 times under a pressure of . Thereafter, it was dried for 3 minutes at room temperature of 30°C and humidity of 60%. The weight was measured using an electronic analytical balance (AEU-130 manufactured by Shimadzu Corporation).

[0123] [Table 2]

[0124]

[0125] <Three-dimensional texture of wood>

[0126] The wood grain decorative films of Examples 2 to 18 and Comparative Examples 1 to 4 were evaluated for their three-dimensional texture by the following method, and the results are shown in Table 3. Light with a wavelength of 380 nm to 780 nm emitted by the International Commission on Illumination (CIE) standard light source D65 was incident on the surface of the wood grain decorative films of the Examples and Comparative Examples at an incident angle of 40° to 85°, and was visually confirmed at an observation angle of 60° from the reflection angle side. The incident angle and observation angle were based on the vertical direction (normal direction) relative to the surface of the wood grain decorative film as a reference (0°).

[0127] Five trained panelists confirmed the difference in contrast between the wood texture print part and the part other than the wood texture print part using the method described above. The contrast of the wood texture print part appeared higher than that of the part other than the wood texture print part. The case where the number of people who could feel the three-dimensional effect was three or more was marked as 0, and the case where the number of people who could feel the three-dimensional effect was two or less was marked as ×.

[0128] [Table 3]

[0129]

[0130] As shown in Table 3, the difference between the matte ink weight of (ii) thick film printing part and the matte ink weight of (i) thin film printing part ((ii)-(i)) is 3.0 g / m 2 In the above Examples 1 to 18, the contrast of the wood texture printing part is higher than that of the parts other than the wood texture printing part, and a three-dimensional effect is felt. On the other hand, the above ((ii)-(i)) is less than 3.0 g / m 2 In Comparative Examples 1 to 4, the difference in thickness between the thick film printed portion overlapping the wood texture printed portion and the thin film printed portion overlapping a portion other than the wood texture printed portion was small, and therefore the wood texture pattern could not be viewed three-dimensionally.

[0131] As a reference, the three-dimensional effect of wood texture will be described using the photographs of Example 3. Figure 8 This is a plan photograph of the wood grain decorative film of Example 3. Fig. 9 This is a photograph of the wood grain decorative film of Example 3 taken from an oblique direction. Fig. 9 This corresponds to the case where the three-dimensional effect of wood texture is evaluated at an incident angle of 45° and an observation angle of 60°. The duct part included in the wood texture printing part is as follows Figure 8 The part printed as black line is shown. Fig. 9 As shown, when light is irradiated and observed from an oblique direction, the portion corresponding to the duct portion appears to be recessed.

[0132] Furthermore, if the overall glossiness is taken into consideration, the scale (depth) of the embossed printing plate corresponding to the film printing portion is set to 7 or more, that is, the matte ink weight of the film printing portion is set to 2.65 g / m 2 The above Examples 1 to 6 are more matte overall compared to Examples 7 to 18, and the three-dimensional sense of wood texture coexists with the overall matte.

[0133] In the above-mentioned embodiments and comparative examples, the scale of the thick film printing part was fixed at 12 for easy comparison of the effect. However, even when the scale of the thick film printing part was changed, the difference in the matte ink weight between the thick film printing part and the thin film printing part was set to 3.0 g / m 2 The above can also present the three-dimensional effect of wood texture.

[0134] Description of Figure Numbers

[0135] 10: Matte printing layer on the surface

[0136] 11: Film printing department

[0137] 12: Thick film printing department

[0138] 20: First thermoplastic resin film

[0139] 30: Back printing layer

[0140] 31: Wood Printing Department

[0141] 32: Parts other than the woodworking printing department

[0142] 40: Second thermoplastic resin film

[0143] 50: Adhesive layer

[0144] 60: Spacer

[0145] 70: Embossing

[0146] 100: Wood grain decorative film

Claims

1. A wood grain decorative film, characterized in that: The invention sequentially comprises a surface matte printing layer, a first thermoplastic resin film, a back printing layer including a wood texture printing part, and a second thermoplastic resin film, wherein the surface matte printing layer is arranged in a manner overlapping with the back printing layer, and comprises a thin film printing part and a thick film printing part, wherein the thick film printing part is arranged in a manner overlapping with the wood texture printing part when viewed from above and is thicker than the thin film printing part, and the matte ink weight of the thick film printing part is 3.0 g / m greater than the matte ink weight of the thin film printing part 2 above.

2. The wood grain decorative film according to claim 1, characterized in that: The matte ink weight of the film printing part is 2.65g / m 2 above.

3. The wood grain decorative film according to claim 1 or 2, characterized in that: The surface matte printing layer comprises silicon oxide.

4. The wood grain decorative film according to any one of claims 1 to 3, characterized in that: The first thermoplastic resin film is a polyvinyl chloride film.

5. The wood grain decorative film according to any one of claims 1 to 4, characterized in that: The second thermoplastic resin film is a polyvinyl chloride film.

6. The wood grain decorative film according to any one of claims 1 to 5, characterized in that: The second thermoplastic resin film is colored.

7. The wood grain decorative film according to any one of claims 1 to 6, characterized in that: The matte surface printed layer has an embossed shape on a surface opposite to the second thermoplastic resin film.

8. The wood grain decorative film according to any one of claims 1 to 7, characterized in that: The second thermoplastic resin film has an adhesive layer on the side opposite to the back printed layer.

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