Decorative molded article and method for producing same

Abstract

The purpose of the present invention is to provide a decorative molded body in which a decorative sheet having both good pencil hardness and easy elongation is used, and in which the decorative sheet and an injection molded body are satisfactorily adhered to each other. A decorative molded article (10) is provided with: an injection molded body (11) comprising an acrylic resin having a Tg of 110-130 DEG C; and a decorative sheet (12) formed on the injection-molded body (11) via an adhesive layer (13) comprising a vinyl chloride-vinyl acetate copolymer resin. A decorative sheet (12) is provided with: a base material (14) comprising an acrylic resin having a Tg of 90-130 DEG C; a hard coat layer (15) formed on the base material; and a reflection prevention layer (16) formed on the hard coat layer (15).

Description

Technical Field

[0001] The present invention relates to a decorative molded article and a method for manufacturing the same, and more particularly to a decorative molded article using a decorative sheet having both good pencil hardness and easy stretchability and a method for manufacturing the same. Background Art

[0002] Hitherto, a decorative molded article has been manufactured by in-mold molding in which a decorative sheet and an injection molded body are integrated in an injection molding die. Such decorative molded articles are used in interior decorations of automobiles, exterior decorations of electric products, cover plates of displays, and the like. For example, Patent Document 1 describes the following: A heat-resistant and high-humidity-resistant decorative sheet using an acrylic resin film is formed into a three-dimensional shape, the formed decorative sheet is disposed in an injection molding die, and then molten resin is injected to integrate the decorative sheet and the injection molded body, thereby manufacturing a cover plate for an in-vehicle display.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-82729. Summary of the Invention

[0006] Technical Problem to be Solved by the Invention

[0007] In the conventional cover plate for a display as described above, in the case where good pencil hardness is required, a hard coat is sometimes used in the decorative sheet. However, in the case where the pencil hardness is improved only by the hard coat, the decorative sheet is sometimes difficult to stretch and cracks are likely to occur. In the case where the decorative sheet is preformed before being disposed in the injection molding die, since the shaping can be performed under relatively mild conditions such as a preliminary heating temperature of about 80°C to 160°C, even if the above-described decorative sheet is used, cracks are not likely to occur. On the other hand, in the injection molding die, in the case where the decorative sheet is formed into a three-dimensional shape, since the shaping is performed only under high-temperature and short-time heating conditions of about 200°C to 400°C and an attracting force, the possibility of generating cracks in the decorative sheet is high. To solve such a technical problem, in the present invention, a decorative sheet having both good pencil hardness and easy stretchability is realized by using an acrylic resin having a high glass transition temperature (Tg) in the base material of the decorative sheet.

[0008] In addition, in the cover plate of a display, polycarbonate resin with high heat resistance is generally used in the injection molded body. However, the polycarbonate resin has a low pencil hardness and a high molding temperature, so there are technical problems such as the decorative sheet being easily damaged and the rainbow appearance being easily generated due to birefringence. Starting from such technical problems, in the present invention, a heat-resistant acrylic resin with a high Tg that can solve these technical problems was studied for use in the injection molded body. However, the following new technical problem was found: it is difficult for the heat-resistant acrylic resin used as the base material of the decorative sheet and the heat-resistant acrylic resin used for the injection molded body to bond to each other, and even if a general adhesive layer is applied between the base material of the decorative sheet and the injection molded body, the base material of the decorative sheet and the injection molded body cannot be well adhered. This technical problem is particularly significant in a portion where the temperature is likely to become low, such as the final filling portion during injection molding.

[0009] The present invention was completed to solve the above technical problems, and its object is to provide a decorative molded body obtained by using a decorative sheet having good pencil hardness and easy stretchability and the decorative sheet being well adhered to the injection molded body.

[0010] Means for solving technical problems

[0011] To achieve the above object, the first invention is a decorative molded product, comprising: an injection molded body composed of an acrylic resin having a glass transition temperature of 110°C to 130°C; an adhesive layer formed on the injection molded body and composed of a vinyl chloride-vinyl acetate copolymer resin; and a decorative sheet formed on the adhesive layer, wherein the decorative sheet has a base material composed of an acrylic resin having a glass transition temperature of 90°C to 130°C, a hard coat formed on the base material, and an antireflection layer formed on the hard coat, and the base material of the decorative sheet is bonded to the injection molded body.

[0012] The decorative molded product of the second invention, based on the first invention, has a pencil hardness of 2B to 3H as measured from the antireflection layer side of the decorative sheet.

[0013] The decorative molded product of the third invention, based on the first invention, when the decorative sheet is at a temperature of 120°C, a 10 mm × 100 mm test piece of the decorative sheet is fixed with a chuck distance of 40 mm and a gauge distance of 40 mm, and a tensile test is performed by applying a load to one end of the test piece at a constant speed of 200 mm / minute, the elongation rate at the time of crack or whitening is 100% to 160%.

[0014] If configured in the manner of the first invention to the third invention, an acrylic resin with a Tg higher than that of a general acrylic resin is used in the injection molded body, so it has heat resistance. In addition, since the injection molded body is an acrylic resin, birefringence is not easily caused. Therefore, even when used for the cover plate of a display, the image is not easily blurred.

[0015] In addition, since an acrylic resin having a Tg higher than that of a general acrylic resin is used in the base material of the decorative sheet, the decorative sheet has both hardness and easy stretchability. Therefore, compared with the case where the pencil hardness of the decorative sheet is improved only by a hard coat, the decorative sheet is less likely to crack while maintaining the hardness.

[0016] Furthermore, since a vinyl chloride-vinyl acetate copolymer resin is used in the adhesive layer, the injection molded body made of an acrylic resin having a high Tg and the base material of the decorative sheet, which are difficult to bond to each other, are well bonded. Therefore, a decorative molded body in which the injection molded body and the base material of the decorative sheet are not easily peeled off is obtained.

[0017] The decorative molded article of the fourth invention is based on the first invention, wherein the hard coat contains acrylic resin beads and has fine irregularities on the surface formed with the antireflection layer.

[0018] If configured in this way, since the hard coat is imparted with a function of suppressing reflected glare by the acrylic resin beads, compared with the case where silica beads, which are usually added particles, are used to suppress reflected glare, a decorative molded article less likely to crack and having high chemical resistance is obtained.

[0019] The decorative molded article of the fifth invention is based on the first invention, and further includes a decorative layer between the adhesive layer and the base material or on the surface of the injection molded body opposite to the surface formed with the adhesive layer.

[0020] The decorative molded article of the sixth invention is based on the first invention, and further includes a base sheet on the surface of the injection molded body opposite to the surface formed with the adhesive layer, and a decorative layer between the base sheet and the injection molded body or on the surface of the base sheet opposite to the surface formed with the injection molded body.

[0021] If configured in the manner of the fifth and sixth inventions, the decorative molded article can be decorated by the decorative layer, and thus various designs can be accommodated.

[0022] The seventh invention is a method for manufacturing a decorated molded article, comprising: a step of preparing a decorative sheet, the decorative sheet including a substrate made of an acrylic resin having a glass transition temperature of 90°C to 130°C, a hard coat formed on the substrate, and an antireflection layer formed on the hard coat; a step of forming an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin on the surface of the substrate opposite to the surface on which the hard coat is formed; a step of arranging the decorative sheet having the adhesive layer formed thereon in an injection molding die having a first die and a second die that forms a cavity between the first die and the second die when the dies are closed, with the antireflection layer facing the cavity surface of the first die of the injection molding die; a step of three-dimensionally molding the decorative sheet having the adhesive layer formed thereon along the shape of the cavity surface of the first die; a step of closing the injection molding die; a step of injecting a molten resin made of an acrylic resin having a glass transition temperature of 90°C to 130°C into the cavity to mold an injection molded body, and at the same time, adhering the decorative sheet to the surface of the injection molded body via the adhesive layer; and a step of opening the injection molding die and taking out the injection molded body.

[0023] The method for manufacturing a decorated molded article according to the eighth invention is based on the seventh invention, and further includes: a step of preparing an insert sheet including a base sheet and a decorative layer formed on the base sheet before the step of closing the injection molding die; and a step of arranging the insert sheet with the base sheet or the decorative layer facing the cavity surface of the second die of the injection molding die, wherein the step of adhering the decorative sheet to the surface of the injection molded body via the adhesive layer is as follows: when injecting a molten resin made of an acrylic resin having a glass transition temperature of 90°C to 130°C into the cavity to mold an injection molded body, adhering the decorative sheet to the surface of the injection molded body on the side of the first die via the adhesive layer, and adhering the base sheet or the decorative layer of the insert sheet to the surface of the injection molded body on the side of the second die.

[0024] If configured in the manner of the seventh invention and the eighth invention, since a vinyl chloride-vinyl acetate copolymer resin is used in the adhesive layer, the injection molded body made of an acrylic resin with a high Tg and the substrate of the decorative sheet made of an acrylic resin with a high Tg are easily adhered, and thus the substrate of the injection molded body and the decorative sheet are not easily peeled off.

[0025] Effects of the Invention

[0026] According to the present invention, a decorated molded article can be obtained in which the decorative sheet has both good pencil hardness and elongation property, and the decorative sheet and the injection molded body are well adhered to each other. Description of the Drawings

[0027] Figure 1 is a perspective view of a decorated molded article according to a first embodiment of the present invention.

[0028] Figure 2 (a) ofFigure 1 Schematic cross-sectional view taken along line II-II shown Figure 2 (b) is a schematic cross-sectional view of the hard coating

[0029] Figure 3 is a schematic cross-sectional view illustrating the manufacturing process of the decorative molded article according to the first embodiment of the present invention

[0030] Figure 4 (a) is a schematic top view of the tensile testing machine Figure 4 (b) is a schematic cross-sectional view of the tensile testing machine

[0031] Figure 5 is a schematic cross-sectional view of the decorative molded article according to the second embodiment of the present invention

[0032] Figure 6 is a schematic cross-sectional view of the decorative molded article according to the third embodiment of the present invention

[0033] Figure 7 is a schematic cross-sectional view of the decorative molded article according to the fourth embodiment of the present invention

[0034] Figure 8 is a schematic cross-sectional view of the decorative molded article according to the fifth embodiment of the present invention

[0035] Figure 9 is a schematic cross-sectional view illustrating the manufacturing process of the decorative molded article according to the fourth embodiment of the present invention Detailed Description of the Invention

[0036] Next, the decorative molded article 10 according to the first embodiment of the present invention will be described with reference to the accompanying drawings

[0037] Refer to Figure 1 , the decorative molded article 10 according to the first embodiment of the present invention has a rectangular shape when viewed from above, and includes a flat portion 61 having a flat plate shape and standing portions 62 standing downward from both sides on the short side of the flat portion 61 at the same height. The two opposed standing portions 62 are connected to the flat portion 61 at an obtuse angle so as to move away from each other as they stand downward

[0038] Refer to Figure 1 and Figure 2 (a) of, the decorative molded article 10 includes an injection molded body 11 and a decorative sheet 12 formed on the injection molded body 11 via an adhesive layer 13. The adhesive layer 13 and the decorative sheet 12 are formed on the side of the injection molded body 11 opposite to the direction in which the standing portions 62 stand

[0039] The decorative sheet 12 includes a base material 14, a hard coat 15 formed on the base material 14, and an antireflection layer 16 formed on the hard coat 15. The base material 14 of the decorative sheet 12 is formed on the injection molded body 11 via an adhesive layer 13. The decorative molded article 10 is applied to, for example, a cover plate of a display, interior decoration of a vehicle, or exterior decoration of an electrified product.

[0040] The injection molded body 11 is made of a heat-resistant acrylic resin having a high glass transition temperature (Tg). The Tg of the injection molded body 11 is, for example, 110°C to 130°C. If the Tg is 110°C or higher, good heat resistance can be obtained even in an environment assuming high temperatures such as a cover plate of a vehicle-mounted display or interior decoration of a vehicle. If the Tg is 130°C or lower, when forming the injection molded body 11 by injection molding, the injection molded body 11 can be molded without making the molding temperature and mold temperature too high, so the decorative sheet 12 formed on the injection molded body 11 is not easily damaged.

[0041] The thickness of the injection molded body 11 is, for example, 1 mm to 4 mm. If the thickness is 1 mm or more, the molten resin during injection molding is not easily cooled in the mold, and the injection molded body 11 and the base material 14 of the decorative sheet 12 are easily adhered. If the thickness is 4 mm or less, shrinkage marks or voids caused by injection molding are not easily generated.

[0042] The base material 14 is made of a heat-resistant acrylic resin having a high Tg. The Tg of the base material 14 is, for example, 90°C to 130°C. If the Tg is 90°C or higher, good pencil hardness can be obtained. If the Tg is 130°C or lower, the base material 14 is not easily embrittled.

[0043] The thickness of the base material 14 is, for example, 90 μm to 250 μm. If the thickness is 90 μm or more, good pencil hardness can be obtained. If the thickness is 250 μm or less, heat is easily transferred to the decorative sheet 12 during molding in the injection molding die, and the decorative sheet is easily elongated.

[0044] The hard coat 15 is a layer that imparts hardness to the decorative molded article. As the material of the hard coat 15, materials that can be crosslinked or cured by energy such as heat, ultraviolet rays, or electron beams can be used. For example, copolymers such as acrylic resins, polyester resins, polyvinyl chloride resins, cellulose resins, rubber resins, polyurethane resins, polyvinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, and ethylene-vinyl acetate copolymer resins can be cited. In the state of the decorative sheet 12 before injection molding, the hard coat 15 can be in a cured state, an uncured state, or a semi-cured state. The uncured or semi-cured hard coat 15 can be cured after manufacturing the decorative molded article 10 using the decorative sheet 12.

[0045] The thickness of the hard coat 15 is, for example, 0.5 μm to 20 μm. If the thickness is 0.5 μm or more, good pencil hardness can be obtained. If the thickness is 20 μm or less, cracks are less likely to occur in the hard coat 15.

[0046] In addition, an antiglare function can also be imparted to the hard coat 15. For example, referring to Figure 2 (b) of, an antiglare function can be imparted by adding acrylic resin beads 65 to the material of the hard coat 15. The average particle diameter of the acrylic resin beads 65 is 0.5 μm to 3 μm. If the average particle diameter is 0.5 μm or more, incident light can be sufficiently diffused. If the average particle diameter is 3 μm or less, glare caused by the acrylic resin beads 65 can be suppressed. Here, the average particle diameter is the average particle diameter of primary particles measured by a laser refraction / scattering type particle size distribution measuring device. The acrylic resin beads may use only acrylic resin beads of the same particle diameter, or may be used in combination with acrylic resin beads of different particle diameters. The hard coat 15 is formed with fine irregularities 66 on the surface forming the antireflection layer 16. The fine irregularities 66 are formed by the acrylic resin beads 65 existing near the surface on the antireflection layer 16 side of the hard coat 15 causing the surface to bulge.

[0047] The antireflection layer 16 is a layer for reducing the light reflected by the external light from the decorative molded article 10. As the material of the antireflection layer 16, for example, a vapor deposition layer of a metal compound such as Al2O3, ZnO2, MgF2, a vapor deposition layer in which a metal compound with a low refractive index such as SiO2, MgF2 and a metal compound with a high refractive index such as ZnO2, TiO2 are laminated, a resin coating composed of a fluorine-based polymer or silica gel, etc. can be used. In addition, a layer combining them can also be used.

[0048] The thickness of the antireflection layer 16 is, for example, 50 nm to 130 nm. If the thickness is 50 nm or more, good pencil hardness can be obtained. When the thickness of the antireflection layer 16 is low, the antireflection layer 16 is easily shaved off, and the change in reflectivity of the shaved portion becomes large, so it will unfortunately become easy to identify damage. On the other hand, if the thickness is 130 nm or less, a good antireflection effect can be obtained. If the thickness of the antireflection layer 16 is too thick, the light reflected at the interface between the antireflection layer 16 and the hard coat 15 and the light reflected on the surface of the antireflection layer 16 are difficult to weaken each other, and sometimes a good antireflection effect cannot be obtained.

[0049] The adhesive layer 13 is a layer for making the base material 14 of the decorative sheet 12 closely adhere to the injection molded body 11. The adhesive layer 13 is composed of a vinyl chloride-vinyl acetate copolymer resin. The thickness of the adhesive layer 13 is, for example, 0.1 μm to 10 μm. If the thickness is 0.1 μm or more, good close adhesion can be obtained. If the thickness is 10 μm or less, a decrease in pencil hardness can be suppressed.

[0050] The pencil hardness of the decorative molded article 10, preferably measured from the antireflection layer 16 side of the decorative sheet 12, is 2B to 3H. The pencil hardness is measured by the following method. The pencil is set at an angle of 45 degrees ± 1 degree with respect to the test surface, and the test surface is scratched such that the length becomes 7 mm or more under a load of 750 g and a speed of 2 mm / s. The hardness at which there are no scratches in three or more of the five times is taken as the pencil hardness of the decorative molded article 10. The pencil hardness of the decorative molded article 10 is preferably not provided only by the hard coat 15, but rather good pencil hardness is obtained by both the acrylic resin having a high Tg as the base material 14 and the hard coat 15. For example, when a high-Tg acrylic resin is not used in the base material 14 and the pencil hardness required for the final decorative molded article 10 is achieved only by the hard coat 15, the decorative sheet 12 is difficult to elongate due to its hardness and cracks are likely to occur. On the other hand, when a high-Tg acrylic resin is used in the base material 14 and the necessary pencil hardness is achieved by combining the hard coat 15 having a lower pencil hardness than necessary and the base material 14, the decorative sheet 12 has both good pencil hardness and easy elongation. Here, the pencil hardness of the hard coat 15 is measured by the same method as that of the decorative molded article 10 in a state where only the hard coat 15 is laminated on the injection molded body 11.

[0051] In addition, the elongation rate of the decorative sheet 12 is preferably 100% to 160%, more preferably 130% to 140%. If the elongation rate is 100% or more, cracks or whitening are less likely to occur in the decorative sheet 12. If the elongation rate is 160% or less, physical properties such as pencil hardness and reflectance are less likely to decrease. The method for measuring the elongation rate of the decorative sheet 12 will be described later.

[0052] As can be seen from the above, the decorative molded article 10 as described above uses an acrylic resin having a higher Tg than a general acrylic resin in the injection molded body 11, and thus has heat resistance. In addition, since an acrylic resin is used in the injection molded body, birefringence is less likely to occur. Therefore, even when used for the cover plate of a display, the image is not likely to become unclear.

[0053] In addition, since an acrylic resin having a higher Tg than a general acrylic resin is used in the base material 14 of the decorative sheet 12, the decorative sheet 12 has both hardness and easy elongation. Therefore, compared with the case where the pencil hardness of the decorative sheet 12 is increased only by the hard coat 15, the decorative sheet 12 is less likely to crack while maintaining hardness.

[0054] Furthermore, since a vinyl chloride-vinyl acetate copolymer resin is used in the adhesive layer 13, the injection molded body 11 made of an acrylic resin with a high Tg and the base material 14 of the decorative sheet 12 made of an acrylic resin with a high Tg, which are difficult to bond to each other, are well bonded. Therefore, a decorative molded article 10 is obtained in which the injection molded body 11 and the base material 14 of the decorative sheet 12 are not easily peeled off.

[0055] Next, a schematic of a method for manufacturing the decorative molded article 10 according to the first embodiment of the present invention will be described with reference to the accompanying drawings.

[0056] Refer to Figure 3 FIG. (a), and prepare the decorative sheet 12. The decorative sheet 12 includes a base material 14, a hard coat 15 formed on the base material 14, and an antireflection layer 16 formed on the hard coat 15. In Figure 3 , the description of each layer of the decorative sheet 12 is omitted. Next, an adhesive layer 13 is formed on the base material 14 of the decorative sheet 12. In the description of the manufacturing method, the "decorative sheet 12 having the adhesive layer 13 formed thereon" is also referred to as the "decorative sheet 12". Next, the decorative sheet 12 is disposed in the injection molding die 80. The injection molding die 80 is composed of a first die 81 and a second die 82. A cavity surface 83 corresponding to the shape of the decorative molded article 10 is formed in the first die 81, and an injection port 84 for injecting molten resin is formed in the second die 82. In addition, by closing the first die 81 and the second die 82, a space is formed between the first die 81 and the second die 82. This space is called a cavity 87. In the step of disposing the decorative sheet 12 in the injection molding die 80, the decorative sheet 12 passes over the guide roller 85 from above the first die 81 and is disposed between the first die 81 and the second die 82 with the antireflection layer 16 facing the cavity surface 83 of the first die 81. Next, the decorative sheet 12 is cut by a cutting edge 86. Next, refer to Figure 3 FIG. (b), and the decorative sheet 12 is three-dimensionally formed along the shape of the cavity surface 83 of the first die 81 by heating at 200°C to 400°C and suction from the first die 81 side. Next, refer to Figure 3 FIG. (c), and the first die 81 and the second die 82 are closed. Next, molten resin made of an acrylic resin having a Tg of 90°C to 130°C is injected from the injection port 84 of the second die 82, and while the injection molded body 11 is formed, the decorative sheet 12 is adhered to the surface of the injection molded body 11 on the first die 81 side via the adhesive layer 13. Next, the injection molding die 80 is opened, and the injection molded body 11 adhered with the decorative sheet 12 is taken out. Next, refer to Figure 3 FIG. (d), and unnecessary portions of the decorative sheet 12 are trimmed by a cutting edge 88, thereby manufacturing the decorative molded article 10.

[0057] The decorative sheet 12 of the present invention can be used particularly effectively as a sheet that is three-dimensionally formed in an injection molding die. Generally, in the method of pre-forming a decorative sheet before injection molding, processing can be performed under mild conditions where the pre-forming heating temperature is 80°C to 160°C. On the other hand, in the method of three-dimensionally forming in an injection molding die, for example, forming is performed only by high-temperature and short-time heating conditions of 200°C to 400°C and suction force, so cracks are likely to occur. In particular, when the pencil hardness is high, cracks are likely to occur. The decorative sheet 12 of the present invention has both good pencil hardness and easy stretchability. Therefore, even when using a sheet that is three-dimensionally formed in an injection molding die, a molded product that is not likely to crack and has good pencil hardness is obtained.

[0058] Next, the functions and effects in the case of using a vinyl chloride-vinyl acetate copolymer resin as the adhesive layer 13 will be described. Referring to Table 1, in Example 1, a vinyl chloride-vinyl acetate copolymer resin (vinyl chloride-vinyl acetate type) was used as the adhesive layer. In Comparative Example 1, no adhesive layer was used. In Comparative Examples 2 and 3, an acrylic resin and a polyester resin were used as the adhesive layer, respectively. In addition, their respective thicknesses are as described in Table 1. For Example 1 and Comparative Examples 1 to 3, the degree of adhesion between the injection molded body and the substrate was confirmed. In addition, in the confirmation of the degree of adhesion, a cross-cut test specified in JIS K5600-5-6 was used. Only Example 1 in which a vinyl chloride-vinyl acetate copolymer resin was used for the adhesive layer had a good adhesion result. In Comparative Example 1 where no adhesive layer was used, the injection molded body and the substrate had poor adhesion, so they did not adhere to each other. In Comparative Example 2, although an acrylic resin, which is a resin of the same system as the resins used in the injection molded body and the substrate, was used, the injection molded body and the substrate did not adhere well. In Comparative Example 3, a commonly used polyester resin was used as the adhesive layer, but the injection molded body and the substrate did not adhere well. As the reason why only the vinyl chloride-vinyl acetate copolymer resin used in Example 1 showed good adhesion, it can be considered that in the vinyl chloride-vinyl acetate copolymer resin, due to the toughness from vinyl chloride and the adhesiveness and plasticity from vinyl acetate, good adhesion is shown.

[0059] [Table 1]

[0060]

[0061] Next, referring to Figure 4 , the method for measuring the elongation rate of the decorative sheet 12 will be described.

[0062] Prepare a test piece 71 of the decorative sheet 12 with a width of 10 mm and a length of 100 mm. Next, grasp the upper part of the test piece 71 with the chuck 72 and grasp the lower part of the test piece 71 with the chuck 73. The positions where the test piece 71 is grasped by the chuck 72 and the chuck 73 are fixed by the screws 74 and 75 formed on the chuck 72 and the chuck 73. The distance between the chuck 72 and the chuck 73 is the inter-chuck distance 76. The distance between the marks 77 is the same as the inter-chuck distance before the test. The elongation rate of the decorative sheet 12 means that under the condition of a temperature of 120 °C, with both the inter-chuck distance and the distance between the marks being 40 mm, fixing the test piece 71 with a width of 10 mm and a length of 100 mm, when the chuck 73 is moved downward at a speed of 200 mm / minute to apply a tensile force to the test piece 71, the elongation rate when cracks or whitening occur on the test piece 71. Here, the elongation rate is (the increase in the inter-chuck distance from before the test to when cracks or whitening occur) ÷ (the inter-chuck distance before the test) × 100 (%). In addition, the "inter-chuck distance before the test" is the inter-chuck distance before applying a tensile force to the test piece 71, which is 40 mm.

[0063] Next, the function and effect in the case of using acrylic resin beads 65 in the hard coat 15 for the purpose of imparting an antiglare function will be described.

[0064] Referring to Table 2, in Example 2, an acrylic-based ultraviolet curable resin added with acrylic resin beads was used in the hard coat. In Comparative Example 4, an acrylic-based ultraviolet curable resin added with silica particles was used in the hard coat. The hard coat was imparted with antiglare properties by the acrylic resin beads and the silica particles. In addition, regarding the materials and thicknesses of the other layers, as described in Table 2. Regarding the antiglare property, both Example 2 and Comparative Example 4 were good. Regarding the moldability, Example 2 was good. On the other hand, in Comparative Example 4, cracks occurred on the decorative sheet after injection molding. Regarding the chemical resistance, in the Gakushin type friction tester (Friction Tester Type II), using a white cotton cloth impregnated with ethanol, under the conditions of a load of 200 g, a reciprocating distance of 100 mm, and a speed of 30 reciprocations / minute, the wear of the surface of the decorative molded product was evaluated. In Example 2, no wear was observed on the surface of the decorative molded product. On the other hand, in Comparative Example 4, damage occurred on the surface of the decorative molded product, and good chemical resistance was not obtained. From the above results, regarding the antiglare property, although both the acrylic resin beads and the silica particles were good, compared with the silica particles, the acrylic resin beads had good moldability and chemical resistance. Depending on the shape and application place of the decorative molded product, it is preferable to use the acrylic resin beads.

[0065] [Table 2]

[0066]

[0067] Next, centering on the differences from the decorative molded article 10 according to the first embodiment, the decorative molded article 20 according to the second embodiment of the present invention will be described.

[0068] Referring to Figure 5 , the decorative molded article 20 is the same in that it is formed by a decorative sheet 22 having a base material 24, a hard coat 25, and an antireflection layer 26, an injection molded body 21, and an adhesive layer 23, but is different from the decorative molded article 10 according to the first embodiment in that the decorative sheet 22 further has a decorative layer 27. The decorative layer 27 is formed on the side of the base material 24 of the decorative sheet 22 opposite to the surface on which the hard coat 25 is formed, and is located between the adhesive layer 23 and the base material 24 of the decorative molded article 20. The lamination order of the other layers is the same as that of the decorative molded article 10 according to the first embodiment.

[0069] The decorative layer 27 is a layer for decorating the decorative molded article 20. The decorative layer 27 is formed of, for example, gravure printing ink. The gravure printing ink contains an adhesive resin, a solvent, and a colorant. Examples of the adhesive resin include vinyl chloride-vinyl acetate copolymer resin, acrylic resin, polyester resin, and polyurethane resin. The solvent is a solvent for dissolving the resin and is selected according to the resin. Examples of the solvent in the gravure printing ink include toluene, methyl ethyl ketone, ethyl acetate, and isopropyl alcohol. The decorative layer 27 is formed, for example, partially on the outer peripheral portion of the decorative molded article 20.

[0070] Regarding the materials of the other layers, they are the same as those of the decorative molded article 10 according to the first embodiment.

[0071] Next, centering on the differences from the previous embodiments, the decorative molded article 30 according to the third embodiment of the present invention will be described.

[0072] Referring to Figure 6 , the decorative molded article 30 is the same in that it is formed by a decorative sheet 32 having a base material 34, a hard coat 35, and an antireflection layer 36, an injection molded body 31, and an adhesive layer 33, but is different from the decorative molded article 10 according to the first embodiment in that the decorative sheet 32 further has a decorative layer 37. In addition, the position where the decorative layer 37 is formed is different from that of the decorative molded article 20 according to the second embodiment. The decorative layer 37 of the decorative molded article 30 is not formed on the decorative sheet 32, but is formed on the side of the injection molded body 31 opposite to the surface on which the adhesive layer 33 is formed.

[0073] The decorative layer 37 is formed, for example, on the injection molded body 31 by silk print after the injection molded body 31 and the decorative sheet 32 are bonded via the adhesive layer 33 by injection molding. The decorative layer 37 can use materials conventionally used in silk print.

[0074] Regarding other layers, they are the same as the decorative molded articles described in the previous embodiments.

[0075] Next, centering on the differences from the previous embodiments, the decorative molded article 40 according to the fourth embodiment of the present invention will be described.

[0076] Refer to Figure 7 , the decorative molded article 40 is the same in that it is formed by a decorative sheet 42 having a base material 44, a hard coat 45, and an antireflection layer 46, an injection molded body 41, and an adhesive layer 43, but is different from the previous embodiments in that an insertion piece 47 is formed on the side of the injection molded body 41 opposite to the surface on which the adhesive layer 43 is formed.

[0077] The insertion piece 47 includes a base sheet 48 and a decorative layer 49 formed on the base sheet 48. The base sheet 48 of the insertion piece 47 is laminated on the injection molded body 41.

[0078] The base sheet 48 is, for example, a thermoplastic resin such as a polypropylene-based resin, a polyethylene-based resin, a polyamide-based resin, an acrylic-based resin, an olefin-based resin, an epoxy-based resin, a polyimide-based resin, a thermoplastic polyurethane, a silicone-based resin, a polyester-based resin, a vinyl chloride-based resin, a polycarbonate-based resin, an ABS-based resin, or a laminate thereof. In addition, the thickness of the base sheet 48 is preferably, for example, 12 μm to 200 μm. If the thickness of the base sheet 48 is 12 μm or more, it has an excellent thickness for workability, and if the thickness is 200 μm or less, it has appropriate rigidity and thus good bendability. It is particularly preferable to use an acrylic-based resin or a polycarbonate-based resin. If an acrylic-based resin or a polycarbonate-based resin is used, the shape followability to the mold becomes better.

[0079] The decorative layer 49 can use the same material as the decorative molded article 20 according to the second embodiment.

[0080] Regarding other layers, they are the same as the decorative molded articles described in the previous embodiments.

[0081] Next, centering on the differences from the manufacturing method of the decorative molded article 10 according to the first embodiment, the manufacturing method of the decorative molded article 40 according to the fourth embodiment will be described.

[0082] Refer to Figure 9 In (a) of, the steps of preparing the decorative sheet 42 and forming the adhesive layer 43 on the decorative sheet are the same. Next, refer to Figure 9 In (b) of, the decorative sheet is arranged on the cavity surface 83 of the first mold of the injection molding die 80, and the insertion piece 47 is arranged such that the decorative layer 49 faces the cavity surface 89 of the second mold 82. Next, refer to Figure 9In (c) thereof, the first mold 81 and the second mold 82 are closed. Then, a molten resin made of an acrylic resin with a Tg of 90°C to 130°C is injected from the injection port 84 of the second mold 82. While molding the injection molded body 41, the decorative sheet 42 is adhered to the surface of the injection molded body 41 on the side of the first mold 81 via the adhesive layer 43, and the surface of the injection molded body 41 on the side of the second mold 82 and the insert piece 47 are adhered. Then, the injection molding die 80 is opened, and the injection molded body 11 adhered with the decorative sheet 12 is taken out. Then, referring to Figure 9 In (d) thereof, the unnecessary portions of the decorative sheet 42 are trimmed using the cutting edge 88, thereby manufacturing the decorated molded article 40.

[0083] Next, centering on the differences from the previous embodiments, the decorated molded article 50 according to the fifth embodiment will be described.

[0084] Referring to Figure 8 , the decorated molded article 50 is the same as the decorated molded article 40 according to the fourth embodiment in that a decorative sheet 52 having a substrate 54, a hard coat 55, and an antireflection layer 56 is formed on one surface of the injection molded body 51, and an insert piece 57 having a base sheet 58 and a decorative layer 59 is formed on the other surface of the injection molded body 51. On the other hand, it is different in that the surface of the insert piece 57 on which the decorative layer 59 is formed is laminated with the injection molded body 51.

[0085] In other aspects, including the manufacturing method, it is the same as the decorated molded article 40 according to the fourth embodiment.

[0086] In addition, in the decorated molded article according to the first embodiment above, it has a three-dimensional shape with a flat portion and a raised portion, but as long as it is a shape that can be formed by injection molding, it can be any shape, and can also be a flat shape or other three-dimensional shapes.

[0087] Furthermore, in the decorated molded articles according to the second to fifth embodiments above, the decorative layer is formed on the outer periphery of the decorated molded article, but as long as the decorated molded article is decorated by the decorative layer, it can also be partially formed at a position other than the outer periphery of the decorated molded article, and in addition, it can also be formed on the entire surface of the decorated molded article.

[0088] Furthermore, in the decorated molded article according to the second embodiment above, the decorative layer is formed using intaglio printing ink, and in the decorated molded article according to the third embodiment, the decorative layer is formed by screen printing. However, as long as the injection molded body can be decorated by the decorative layer, the decorative layer can also be formed by other inks or printing methods.

[0089] Furthermore, in the manufacturing method of the decorative molded article according to each of the above-described embodiments, an injection molding die having an injection port in the second die is used, but as long as the molten resin can be injected from the injection port into the cavity of the injection molding die, the injection port may be disposed in either the first die or the second die.

[0090] Description of Reference Numerals

[0091] 10, decorative molded article; 11, injection molded body; 12, decorative sheet; 13, adhesive layer; 14, base material; 15, hard coat; 16, antireflection layer; 20, decorative molded article; 21, injection molded body; 22, decorative sheet; 23, adhesive layer; 24, base material; 25, hard coat; 26, antireflection layer; 27, decorative layer; 30, decorative molded article; 31, injection molded body; 32, decorative sheet; 33, adhesive layer; 34, base material; 35, hard coat; 36, antireflection layer; 37, decorative layer; 40, decorative molded article; 41, injection molded body; 42, decorative sheet; 43, adhesive layer; 44, base material; 45, hard coat; 46, antireflection layer; 48, base sheet; 49, decorative layer; 50, decorative molded article; 51, injection molded body; 52, decorative sheet; 53, adhesive layer; 54, base material; 55, hard coat; 56, antireflection layer; 58, base sheet; 59, decorative layer; 65, acrylic resin beads; 66, fine unevenness; 71, test piece; 76, distance between chucks; 77, distance between marks; 80, injection molding die; 81, first die; 82, second die; 83, cavity surface; 87, cavity; 89, cavity surface.

Claims

1. A decorative molded article, comprising: An injection molded body made of an acrylic resin having a glass transition temperature of 110°C to 130°C; An adhesive layer formed on the injection molded body and made of a vinyl chloride-vinyl acetate copolymer resin; and A decorative sheet formed on the adhesive layer, The decorative sheet having a substrate made of an acrylic resin having a glass transition temperature of 90°C to 130°C, a hard coat formed on the substrate, and an antireflection layer formed on the hard coat, The substrate of the decorative sheet being bonded to the injection molded body.

2. The decorative molded article according to claim 1, wherein The pencil hardness measured from the antireflection layer side of the decorative sheet is 2B to 3H.

3. The decorative molded article according to claim 1, wherein When the decorative sheet is at a temperature of 120°C, a test piece of the decorative sheet having a size of 10 mm × 100 mm is fixed with a chuck distance of 40 mm and a gauge distance of 40 mm, and a tensile test is performed by applying a load to one end of the test piece at a constant speed of 200 mm / minute, the elongation rate at the time of crack or whitening is 100% to 160%.

4. The decorative molded article according to claim 1, wherein The hard coat contains acrylic resin beads and has fine irregularities on the surface where the antireflection layer is formed.

5. The decorative molded article according to claim 1, wherein An additional decorative layer is provided between the adhesive layer and the substrate or on the surface of the injection molded body opposite to the surface where the adhesive layer is formed.

6. The decorative molded article according to claim 1, wherein A base sheet is further provided on the surface of the injection molded body opposite to the surface where the adhesive layer is formed, An additional decorative layer is provided between the base sheet and the injection molded body or on the surface of the base sheet opposite to the surface where the injection molded body is formed.

7. A method for manufacturing a decorative molded article, comprising: A step of preparing a decorative sheet, the decorative sheet having a substrate made of an acrylic resin having a glass transition temperature of 90°C to 130°C, a hard coat formed on the substrate, and an antireflection layer formed on the hard coat; A step of forming an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin on the surface of the substrate opposite to the surface where the hard coat is formed; A step of arranging the decorative sheet having the adhesive layer formed thereon in an injection molding die having a first die and a second die that forms a cavity between the first die when the dies are closed, with the antireflection layer facing the cavity surface of the first die of the injection molding die; A step of three-dimensionally molding the decorative sheet having the adhesive layer formed thereon along the shape of the cavity surface of the first die; A step of closing the injection molding die; A step of injecting a molten resin made of an acrylic resin having a glass transition temperature of 90°C to 130°C into the cavity to mold an injection molded body, and simultaneously adhering the decorative sheet to the surface of the injection molded body via the adhesive layer; and A step of opening the injection molding die and taking out the injection molded body.

8. The manufacturing method of the decorative molded article according to claim 7 further comprises: Before the step of clamping the injection molding die, a step of preparing an insert sheet having a base sheet and a decorative layer formed on the base sheet; and a step of disposing the insert sheet such that the base sheet or the decorative layer faces the cavity surface of the second die of the injection molding die, The step of adhering the decorative sheet to the surface of the injection molded body via the adhesive layer is as follows: While injecting a molten resin composed of an acrylic resin having a glass transition temperature of 90°C to 130°C into the cavity to mold the injection molded body, the decorative sheet is adhered via the adhesive layer to the surface of the injection molded body on the first die side, and the base sheet or the decorative layer of the insert sheet is adhered to the surface of the injection molded body on the second die side.

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