Decorative material

Abstract

To provide a film decorative sheet through inkjet printing with an aqueous inkjet ink.SOLUTION: According to one aspect of the present invention, a decorative sheet 1 comprises a film base material 11, a pattern layer 13, an overcoat layer 14, and a top clear layer 15 in this order, where the overcoat layer is mainly composed of a water-based resin, and the pattern layer is formed through inkjet printing with an aqueous inkjet ink.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a decorative material. [Background technology]

[0002] Conventionally, when it comes to decorative materials, when the target material is a film-based substrate such as polyvinyl chloride, design has been imparted by providing a pattern layer formed by gravure printing using ink containing organic solvents. However, gravure inks containing such organic solvents contain volatile organic compounds (VOCs) such as toluene and ethyl acetate, which have a high environmental impact and are harmful to the human body, posing a problem from the perspective of environmental considerations.

[0003] On the other hand, water-based inks are preferable because they are less toxic and odorous than solvent-based inks and have a smaller environmental impact. However, although water-based inks are used in the field of flexible packaging, they are not widely used in the field of building materials, and there are no long-length printing machines that can print building materials. Summary of the Invention [Problem to be solved by the invention]

[0004] When a gravure ink containing an organic solvent is used to form the pattern layer, the adhesion between the substrate and the upper clear layer can be improved by applying a heat press treatment to heat and press the substrate's pattern layer-forming surface and the upper clear layer. On the other hand, when a water-based ink is used, the adhesion between the ink and the upper clear layer is low and there is a risk of peeling. In particular, when the pattern is a dark color, the surface area ratio of the water-based ink to the layer surface is large, so the adhesion is significantly reduced and there is a risk of the upper clear layer peeling off.

[0005] In view of the above problems, the present invention aims to provide a decorative sheet that can maintain adhesion even when the pattern is a dark color, and that can ensure design while reducing the environmental load. [Means for solving the problem]

[0006] In order to solve the above problems, a decorative sheet in one embodiment of the present invention comprises, at least in this order, a film base material, a design layer, an overcoat layer, and an upper clear layer, the design layer being formed by inkjet printing using a water-based ink, and the overcoat layer being formed using a water-based resin. Effect of the Invention

[0007] According to one aspect of the present invention, even when the pattern layer is formed by inkjet printing using aqueous ink, a decorative material can be provided which has excellent adhesion between the base material, the pattern layer, and the upper clear layer, has high designability, and is capable of reducing the environmental impact. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view showing the configuration of a decorative sheet in one embodiment of the present invention when the pattern of the pattern layer 13 is a light color. [Diagram 2] FIG. 2 is a cross-sectional view showing the configuration of a decorative sheet in one embodiment of the present invention when the pattern of the pattern layer 13 is a dark color. [Diagram 3] FIG. 2 is a cross-sectional view showing the configuration of a decorative sheet in another embodiment of the present invention, in which the pattern of the pattern layer 13 is a light color. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The decorative sheet according to the present embodiment will be described below through the embodiments, but the following embodiments do not limit the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0010] As shown in Fig. 1, the decorative sheet 1 according to this embodiment comprises a film substrate 11, a primer layer 12, a design layer 13, an overcoat layer 14, and an upper clear layer 15, in this order. If the film substrate 11 and the overcoat layer have sufficient interlayer strength, the primer layer 12 does not need to be provided, as shown in Fig. 3. That is, the decorative sheet 1 according to the present invention comprises at least the film substrate 11, the design layer 13, the overcoat layer 14, and the upper clear layer 15, in this order. Each component of the decorative sheet 1 shown in FIG. 1 will now be described in detail.

[0011] <Film substrate> The film substrate 11 is a layer that serves as the base material of the decorative sheet 1. The film substrate 11 can be formed from a resin material such as polyvinyl chloride (PVC) resin, acrylonitrile-butadiene-styrene copolymer (ABS) resin, polycarbonate (PC) resin, nylon resin, acrylic resin, polystyrene resin, polyethylene terephthalate (PET) resin, or the like.

[0012] The resin forming the film substrate 11 can be toned to match the color of the pattern of the pattern layer 13 described below. For example, when forming a pale-colored pattern, the color can be toned to a bright color such as white, and when forming a dark-colored pattern, the color can be toned to a dark color.

[0013] The film substrate 11 is not particularly limited, but is preferably in the form of a flat plate (particularly, a sheet). The thickness of the film substrate 11 is not particularly limited as long as it is excellent in strength, rigidity, impact resistance, heat resistance, cold resistance, processability, etc., required for the substrate of the decorative sheet 1, and is easy to process, but for example, it is preferably 50 μm or more and 400 μm or less, and more preferably 50 μm or more and 150 μm or less. When the thickness is 50 μm or more, the strength, rigidity, impact resistance, heat resistance, and cold resistance required for the substrate of the decorative sheet 1 are good. Also, when the thickness is 400 μm or less, the processability of the decorative sheet 1, such as cuttability and bendability, is improved.

[0014] <Primer layer> The primer layer 12 can be provided between the film substrate layer 11 and the pattern layer 13, and is a layer for achieving good adhesion between the substrate film 11 and the pattern layer 13, and between the substrate film 11 and the overcoat layer. In this embodiment, the method for forming the primer layer 12 is not particularly limited. For the primer layer 12, a water-based resin such as an ethylene-vinyl acetate copolymer can be used.

[0015] The thickness of the primer layer 12 is preferably from 1 μm to 30 μm, and more preferably from 2 μm to 10 μm. If the thickness is less than 1 μm, it is difficult to improve the adhesion between the base film 11 and the overcoat layer 14 even if the primer layer is formed.

[0016] When the film substrate 11 and the overcoat layer have sufficient interlayer strength, the primer layer 12 does not need to be provided.

[0017] <Pattern layer> The pattern layer 13 is a layer provided on the primer layer 12 for adding a pattern to impart design. The pattern layer 13 may cover the entire surface of the primer layer 12 or may cover only a part of it. For example, when the pattern layer 13 has a planar shape corresponding to an arbitrary pattern, information, or the like, the pattern layer 13 is formed so as to partially cover the surface of the primer layer 12. The pattern layer 13 is applied by inkjet printing using a water-based inkjet ink. At this time, the pattern layer 13 is formed by a plurality of dots printed on the surface of the primer layer 12. The ink formed in dots may be printed separately from each other or may be printed overlapping each other. This eliminates the limitation on the size of the pattern of the pattern layer 13, and allows the pattern layer 13 to have a high-quality and fine pattern. Inkjet printing does not require the printing plate to have unevenness corresponding to the pattern, as in gravure printing or offset printing. This makes it possible to form a pattern that is finer than the upper limit of metal processing technology.

[0018] Furthermore, by forming the design layer 13 using aqueous inkjet ink, it is possible to reduce the amount of volatile organic compounds (VOCs) used, compared to a configuration in which the design layer is formed using solvent ink. In particular, in decorative sheets using polyvinyl chloride resins, the design layer is often formed using solvent ink, but by using aqueous inkjet ink, the environmental impact can be reduced.

[0019] The aqueous inkjet ink contains, for example, an aqueous solvent or a colorant dispersed in the aqueous solvent, and may contain other additives. For the design layer 13, a known aqueous ink for inkjet printing can be used. As the colorant, for example, a pigment or a dye can be used. A pigment is preferably used from the viewpoints of water resistance, light resistance, and resistance to deterioration (discoloration, etc.) due to the water resistance and light resistance. In addition, a dye has a very small particle size and a low viscosity, so that the viscosity is not likely to increase even if the ratio of the dye component in the ink is increased, and since it is easily dissolved in a solvent, there is no need to add a dispersant, which is one of the factors that increases the viscosity, and therefore, it is preferable in that high colorability and flatness of printing can be achieved at the same time.

[0020] The pattern of the pattern layer 13 may be any pattern, such as wood grain, stone grain, fabric grain, abstract patterns, geometric patterns, letters, symbols, solid colors, or combinations of these.

[0021] The shading of the pattern of the pattern layer 13 can be determined arbitrarily, but as the shading of the pattern becomes darker, as shown in FIG. 2, the proportion of the ink formed in the dots described above to the surface area of ​​the film substrate 11 or the primer layer 12 increases, and the contact area between the overcoat layer 14 and the film substrate 11 or the primer layer 12 decreases, so that the upper clear layer 15 described below and the film substrate 11 become more likely to peel off. Specifically, the shading of the pattern of the pattern layer 13 is preferably such that the proportion of the dots made of aqueous inkjet ink to the entire area of ​​the film substrate is 90% or less, more preferably 70% or less, and even more preferably 50% or less. In addition, if the proportion of the dots made of aqueous inkjet ink is 20% or more, the print quality and design can be maintained.

[0022] The thickness of the pattern layer 13 is preferably 1 μm or more and 20 μm or less. When the thickness of the pattern layer 13 is 1 μm or more, the printing can be made clear. When the thickness of the pattern layer 5 is 20 μm or less, the printing workability during the production of the decorative sheet 1 is improved, and the production cost can be reduced.

[0023] The design layer 13 is preferably formed using at least four colors of water-based inkjet inks. When the design layer 13 is formed using four or more colors of ink, the decorative sheet 1 is imparted with high quality and high designability. When the above-mentioned water-based ink is used, the design layer 13 is formed by drying the ink for a predetermined period of time using, for example, a dryer.

[0024] <Overcoat layer> The overcoat layer 14 is provided between the pattern layer 13 and the upper clear layer 15, and is a layer for ensuring good adhesion between the primer layer 12 and the upper clear layer. By providing the overcoat layer 14, the overcoat layer and the primer layer 12, and the overcoat layer and the upper clear layer are bonded with high interlayer strength, and as a result, the interlayer strength between the film substrate 11 and the upper clear layer 15 can be improved. In addition, the overcoat layer 14 can fill in the steps on the pattern layer surface caused by the water-based inkjet ink due to the shading of the pattern, and can increase the contact area between the primer layer 12 and the overcoat layer 14.

[0025] The overcoat layer 14 is formed of a water-based resin that has good adhesion to each of the film substrate 11, the primer layer 12, and the upper clear layer 15. For example, acrylic-vinyl chloride resins, vinyl chloride-vinyl acetate copolymer resins, polyurethane resins, etc. are preferred, and vinyl chloride acrylic resins are particularly preferred.

[0026] The amount of resin material applied in the overcoat layer is 2 g / m 2 More than 7g / m 2 It is preferable that the coating amount is 1 μm or less. Here, the coating amount is the coating amount after the resin material is coated and dried. The thickness of the overcoat layer 14 formed by coating the resin material in such a coating amount is preferably 1 μm or more and 30 μm or less. When the thickness of the overcoat layer 14 is 1 μm or more, the thickness of the overcoat layer 14 is sufficient to fill the steps of the picture layer 12 well, and the interlayer strength between the film substrate 11 and the upper clear layer 15 can be further improved. In addition, when the thickness of the overcoat layer 14 is 5 μm or less, the overcoat layer 14 is less likely to attack the film substrate 11.

[0027] <Upper platform clear layer> The upper stand clear layer 15 is a layer for protecting the picture layer 13. The upper stand clear layer 15 is preferably formed from a resin material similar to that of the film substrate 11, and more preferably from the same resin material as the film substrate 11. This is because it makes it easier to select the material of the overcoat layer 14, and the interlayer strength between the film substrate 11 and the upper stand clear layer 15 is easily improved.

[0028] The thickness of the upper clear layer 15 is not particularly limited, but is preferably 50 μm to 400 μm, and more preferably 50 μm to 150 μm. If the thickness is 50 μm or more, the upper clear layer 15 itself may lack strength, and durability and weather resistance may decrease. Also, if the thickness is 400 μm or less, the film has a suitable stiffness, making it easy to attach to the film substrate 11.

[0029] The upper clear layer 15 may be given any design, so long as the design of the picture layer 13 appears on the surface of the decorative sheet 1. For example, the surface layer 14 may be given any color or pattern (design). The design may be given to the entire surface of the upper clear layer 15, or may be given partially. The method of giving the design is not particularly limited, and examples include embossing. The design of the upper clear layer 15 can be changed depending on the embossing specifications.

[0030] The upper clear layer 15 may contain various additives such as weathering agents, plasticizers, stabilizers, fillers, dispersants, colorants such as dyes and pigments, solvents, ultraviolet absorbers, heat stabilizers, light stabilizers, antiblocking agents, catalyst traps, colorants, light scattering agents, and gloss adjusters, as necessary. In addition, the upper clear layer 15 may contain functional additives such as antibacterial agents and antifungal agents, as necessary. In this embodiment, the method of forming the upper clear layer is not particularly limited.

[0031] <Manufacturing method of decorative materials> An example of a method for producing a decorative sheet will now be described.

[0032] The film substrate 11 can be obtained by forming a resin material into a sheet by a molding method such as injection molding, extrusion molding, blow molding, vacuum molding, compression molding, calendar molding, or fused lamination molding.

[0033] First, a water-based resin (for example, an ethylene-vinyl acetate copolymer) is applied onto the film substrate 11 and then dried to form the primer layer 12. Next, a pattern is formed on the primer layer 12 by inkjet printing using a water-based inkjet ink, and then dried to form a pattern layer 13. Next, an aqueous resin (for example, an acrylic-vinyl chloride resin, a vinyl chloride-vinyl acetate copolymer resin, a polyurethane resin, etc.) is applied onto the design layer 13 and dried to form an overcoat layer 14. Finally, a transparent resin material (for example, a transparent vinyl chloride resin) is applied onto the overcoat layer 14 and cured to form the upper platform clear layer 15. In this manner, the decorative sheet 1 is formed.

[0034] <Effects of this embodiment> The decorative sheet 1 of this embodiment can provide the effects described below. (1) The decorative sheet 1 of this embodiment comprises, in this order, a film substrate 11, a design layer 13, an overcoat layer 14, and an upper clear layer 15, the design layer 13 being formed using an aqueous inkjet ink, and the overcoat layer 14 being formed containing an aqueous resin. This makes it possible to improve the interlayer strength between the film substrate layer 11 and the upper clear layer 15 in the decorative sheet 1, improve the design, and reduce the environmental impact. (2) Furthermore, in the decorative sheet 1 according to this embodiment, a primer layer 12 containing a water-based resin is provided between the film substrate 11 and the design layer 13. This further improves the adhesion between the layers, and even if an additional primer layer 12 is provided, the reduction in environmental impact can be maintained. (3) Furthermore, in the decorative sheet 1 according to this embodiment, the overcoat layer 14 is formed using a water-based resin such as a vinyl chloride acrylic resin, a vinyl chloride acetate resin, or a polyurethane resin. This improves the interlayer strength between the film substrate layer 11 and the upper clear layer 15, and suppresses interlayer delamination originating from the design layer inkjet printed using aqueous inkjet ink, which is usually prone to peeling. (4) Additionally, in the design layer 13 of the decorative sheet 1 according to this embodiment, the proportion of dots formed by aqueous inkjet ink to the total area of ​​the film substrate is 20% or more and 90% or less. This increases the contact area between the overcoat layer 14 and the film base layer 11 or the primer layer 12, and improves the adhesion between the film base layer 11 and the upper clear layer 15. EXAMPLES

[0035] The decorative sheet according to this embodiment will be described below with reference to examples. In the examples, decorative sheets having the configurations explained in the above embodiments were produced and evaluated as described below.

[0036] <Example 1> A polyvinyl chloride resin film was used as the film substrate 11, and an aqueous resin mainly composed of an ethylene-vinyl acetate copolymer was applied to one side of the film substrate 11 using a bar coater, and then dried for 60 seconds in an environment of 40°C to form a primer layer 12. Next, a design was printed on top of the primer layer 12 using aqueous inkjet ink with an inkjet printer at 1200 dpi, CMYK colors, roll-to-roll, with light shades of the pattern (the proportion of dots made of aqueous inkjet ink to the total area of ​​the film substrate was 40%), to form a pattern layer 13. Next, an acrylic / vinyl chloride-based overcoat agent (Seiko PMC Corporation's "Hicross-X-BE-7500") was applied onto the design layer 13 and then dried to form an overcoat layer 14. A transparent vinyl chloride resin film was laminated on the formed overcoat layer 14, and then heat-adhered to form an upper clear layer 15, thereby producing the decorative sheet of Example 1.

[0037] <Example 2> The decorative sheet of Example 2 was produced in the same manner as Example 1, except that the shading of the pattern in the pattern layer 13 was formed to be a dark color (the proportion of dots made of water-based inkjet ink to the total area of ​​the film substrate was 90%).

[0038] <Example 3> The decorative sheet of Example 3 was produced in the same manner as Example 1, except that a vinyl chloride-vinyl acetate copolymer (Vinyl Chloride-Vinyl Acetate)-based overcoat agent ("Vinyblan 603" from Nissin Chemical Industry Co., Ltd.) was used as the overcoat agent.

[0039] <Example 4> The decorative sheet of Example 4 was produced in the same manner as Example 3, except that the shading of the pattern in the pattern layer 13 was formed to be a dark color (the proportion of dots made of water-based inkjet ink to the total area of ​​the film substrate was 90%).

[0040] <Example 5> A decorative sheet of Example 5 was produced in the same manner as Example 1, except that a polyurethane-based overcoat agent ("MZ-480" by Takamatsu Oil & Fat Co., Ltd.) was used as the overcoat agent.

[0041] <Example 6> The decorative sheet of Example 6 was produced in the same manner as Example 5, except that the shading of the pattern in the pattern layer 13 was formed to be a dark color (the proportion of dots made of water-based inkjet ink to the total area of ​​the film substrate was 90%).

[0042] <Comparative Example 1> A decorative sheet of Comparative Example 1 was formed in the same manner as in Example 1, except that the overcoat layer 14 was not formed.

[0043] <Comparative Example 2> A decorative sheet of Comparative Example 1 was formed in the same manner as in Example 2, except that the overcoat layer 14 was not formed.

[0044] <Comparative Example 3> A decorative sheet of Comparative Example 3 was formed in the same manner as in Example 1, except that the ink for forming the design layer 13 was an oil-based inkjet ink.

[0045] <Comparative Example 4> A decorative sheet of Comparative Example 4 was formed in the same manner as in Example 2, except that the ink for forming the design layer 13 was an oil-based inkjet ink.

[0046] <Comparative Example 5> A decorative sheet of Comparative Example 5 was formed in the same manner as in Example 3, except that the ink for forming the design layer 13 was an oil-based inkjet ink.

[0047] <Comparative Example 6> A decorative sheet of Comparative Example 6 was formed in the same manner as in Example 4, except that the ink for forming the design layer 13 was an oil-based inkjet ink.

[0048] <Comparative Example 7> A decorative sheet of Comparative Example 7 was formed in the same manner as in Example 5, except that the ink for forming the design layer 13 was an oil-based inkjet ink.

[0049] <Comparative Example 8> A decorative sheet of Comparative Example 8 was formed in the same manner as in Example 6, except that the ink for forming the design layer 13 was an oil-based inkjet ink.

[0050] <Evaluation> The decorative sheets of the above-mentioned Examples and Comparative Examples were evaluated as follows.

[0051] (Design) The design printed on the surface of each of the decorative sheets of Examples 1 to 6 and Comparative Examples 1 to 8 was visually inspected and rated on the following four-level scale of ⊚, ◯, △, and ×. <Evaluation criteria> ◎: No streaks or gaps in the design, no problems 〇: There are few streaks or gaps in the design, and it is at a level where there are no problems. △: There are some streaks or gaps in the design, but they are not a problem when viewed from a distance. ×: There are many streaks and gaps in the design, making it unusable

[0052] (Adhesion) For each of the decorative sheets of Examples 1 to 6 and Comparative Examples 1 to 8, the interlayer strength (N / inch) between the film substrate 11 and the upper clear layer 15 was measured and evaluated using the following four levels of ◎, ○, △, and ×. The interlayer strength was measured when the upper clear layer 15 was peeled off from the film substrate 11 with a sample width of 1 inch, a test force of 50 kgf, and a tensile speed of 200 mm / min. <Evaluation criteria> ◎: Interlaminar strength is 10N / inch or more ○: Interlaminar strength is 5N / inch or more and less than 10N / inch △: Interlaminar strength is 1N / inch or more and less than 5N / inch ×: Interlaminar strength is less than 1N / inch

[0053] (Environmental Considerations) In terms of environmental friendliness, the products using water-based inkjet inks were rated as ⊚, while the products using oil-based inkjet inks were rated as x.

[0054] Table 1 shows excerpts of the configurations of Examples 1 to 6 and Comparative Examples 1 to 8 and the evaluation results.

[0055] [Table 1]

[0056] (Design evaluation) As shown in Table 1, the design results for Examples 1 to 6 and Comparative Examples 3 to 8 show that the design is better when water-based inkjet inks are used than when oil-based inkjet inks are used, as in Examples 1 to 6. This is thought to be because water-based inks have better ink ejection performance than oil-based inks, resulting in more stable print quality.

[0057] (Adhesion evaluation) From the adhesion results of Examples 1 to 6, it was found that regardless of whether the overcoat layer 14 was formed using a vinyl chloride acrylic, vinyl chloride acetate, or polyurethane overcoat resin material, a decorative sheet in which the film substrate 11 and the upper clear layer 15 were in close contact was obtained, regardless of the shading of the picture layer. Furthermore, when Examples 1 and 2 are compared, it was found that Example 1, in which the pattern of the pattern layer 13 is a light color, has better adhesion than Example 2, in which the pattern is a dark color. This is thought to be because when a light-colored pattern is printed by inkjet printing, the spacing between the dots constituting the pattern becomes wider compared to when the pattern is a dark color, and the area where the overcoat layer 14 comes into direct contact with the primer layer 12 increases, improving the interlayer strength. Furthermore, in Comparative Example 2, which does not have an overcoat layer and has a dark pattern on the pattern layer 13, the upper base clear layer 15 and the film base 11 naturally peel off and the adhesion is lost, whereas in Examples 2, 4, and 6, which have an overcoat layer, the film base 11 and the upper base clear layer have adhesion. This is thought to be because the overcoat layer 14 has better adhesion to the primer layer 12 than the upper base clear layer, and has sufficient adhesive strength even with a small ground contact area. In other words, it shows that by providing an overcoat layer, the film base 11 and the upper base clear layer 15 can be easily adhered to each other even when the pattern on the pattern layer 13 is dark.

[0058] (comprehensive evaluation) In actual decorative sheets, the shade of the pattern of the pattern layer often varies within the decorative sheet, with some parts of the decorative sheet being dark and other parts being light. Therefore, in actual decorative sheets, having adhesion is required to have adhesion in both dark and light colors. In Examples 1 and 2, in which the overcoat layer is made of a PVC-based overcoat agent, the adhesion evaluation was rated as ⊚ for light colors and ◯ for dark colors, and it can be said that the adhesiveness is excellent even in an actual decorative sheet in which light and dark colored parts are combined. This is thought to be due to the good adhesiveness between the PVC-acrylic overcoat agent and the resin forming the primer layer 12, and between the PVC-acrylic overcoat agent and the resin forming the upper base clear layer 15. On the other hand, in Comparative Examples 1 and 2, which did not have an overcoat layer, adhesion was shown in light colors and the evaluation was ◯, but as mentioned above, there was no adhesion in dark colors and they peeled off, and the evaluation was ×. This shows that in an actual decorative sheet, although the light colored parts adhere well, the upper clear layer peels off in the dark colored parts, so the durability and weather resistance of the entire decorative sheet is reduced, and it can be said that it is unsuitable as a decorative sheet. [Explanation of symbols]

[0059] 1...decorative sheet, 11...film base material, 12...primer layer, 13...pattern layer, 14...overcoat layer, 15...upper clear layer

Claims

1. The film substrate, the pattern layer, the overcoat layer, and the upper clear layer are provided in this order. The design layer is formed by inkjet printing using a water-based inkjet ink, The overcoat layer is a decorative sheet formed using a water-based resin.

2. The decorative sheet according to claim 1 , further comprising a primer layer formed of a water-based resin between the film substrate and the design layer.

3. 3. The decorative sheet according to claim 1, wherein the aqueous resin forming the overcoat layer is a vinyl chloride acrylic resin, a vinyl chloride acetate resin, or a polyurethane resin.

4. 3. The decorative sheet according to claim 1, wherein the proportion of the dots formed by the aqueous inkjet ink forming the pattern of the pattern layer relative to the total area of ​​the film substrate is 20% or more and 90% or less.

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