Resin sheet, laminate, molded body, and method for manufacturing molded body

Abstract

To provide a resin sheet which has high chroma, and deep appearance.SOLUTION: A resin sheet contains polypropylene containing a smectic crystal, and an interference pearl pigment.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin sheet, a laminate, a molded article, and a method for manufacturing a molded article. [Background technology]

[0002] Painting is used as a method to improve the appearance of products in a variety of fields, including automobiles, home appliances, building materials, daily necessities, and information and communication devices. However, painting is a method that places a heavy burden on the environment, as it emits large amounts of VOCs. Furthermore, temperature and humidity control in the paint booth and the baking process consume a large amount of energy and emit large amounts of carbon dioxide. In particular, painting accounts for 20% of the carbon dioxide emitted in the production of new cars. To reduce these environmental impacts, alternative methods to painting are being actively developed.

[0003] As an alternative method to painting molded articles, for example, Patent Document 1 discloses a technology for obtaining molded articles with a flip-flop appearance by using a resin composition having a specific composition containing a pearl pigment or the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-9034 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the method disclosed in Patent Document 1 has problems such as low saturation of the molded product and poor depth of design due to the loss of color development of the pearl pigment. Furthermore, although it is necessary to increase the amount of pearl pigment added to improve color development, even if the pearl pigment is added at a high concentration, it is difficult to improve the depth of the design. An object of the present invention is to provide a resin sheet having high color saturation and a deep appearance. [Means for solving the problem]

[0006] According to the present invention, the following resin sheet and the like are provided. 1. A resin sheet containing polypropylene containing smectite crystals and an interference pearl pigment. 2. The resin sheet according to 1, wherein the polypropylene has an isotactic pendant fraction of 85 mol % to 99 mol %. 3. The crystallization rate of the polypropylene at 130°C is 2.5 min -1 3. A resin sheet according to 1 or 2 below. 4. The resin sheet according to any one of 1 to 3, wherein the polypropylene has an exothermic peak of 1 J / g or more on the low-temperature side of the maximum endothermic peak in a curve obtained by differential scanning calorimetry. 5. The resin sheet according to any one of 1 to 4, wherein the interference pearl pigment is one or more selected from the group consisting of titanium oxide-coated mica, titanium oxide-coated glass, and titanium oxide-coated alumina. 6. The resin sheet according to any one of 1 to 5, wherein the content of the interference pearl pigment is 0.01% by mass or more and 20% by mass or less. 7. A laminate comprising a first layer containing polypropylene containing smectic crystals and a second layer made of the resin sheet according to any one of 1 to 6. 8. The laminate according to 7, further comprising a third layer on the side of the second layer opposite the first layer, the third layer comprising a thermoplastic resin and a colorant. 9. A laminate comprising the resin sheet according to any one of 1 to 6 and an easy-adhesion layer. 10. The laminate according to 9, wherein the easy-adhesion layer contains one or more resins selected from the group consisting of urethane, acrylic, polyolefin, and polyester. 11. The laminate according to 9 or 10, which has a printed layer on the surface of the easy-adhesion layer opposite to the resin sheet. 12. A molded article produced using the resin sheet according to any one of 1 to 6 or the laminate according to any one of 7 to 11. 13. A method for producing a molded article, comprising molding the resin sheet according to any one of 1 to 6 or the laminate according to any one of 7 to 11 to obtain a molded article. 14. Placing the resin sheet or the laminate on a mold; and By supplying a molding resin toward the resin sheet or the laminate, the resin sheet or the laminate is shaped to fit the mold, and the molding resin and the resin sheet or the laminate are integrated. 14. A method for producing the molded article according to 13, comprising: 15. Shaping the resin sheet or the laminate to fit a mold; and The molding resin is supplied toward the shaped resin sheet or the shaped laminate, thereby integrating the molding resin with the shaped resin sheet or the shaped laminate. 14. A method for producing the molded article according to 13, comprising: 16. Heating the resin sheet or the laminate and placing it on the cavity surface of a mold, and shaping the resin sheet or the laminate to match the shape of the mold; and The molding resin is supplied toward the shaped resin sheet or the shaped laminate, thereby integrating the molding resin with the shaped resin sheet or the shaped laminate. 14. A method for producing the molded article according to 13, comprising: 17. A method for producing a molded body described in 13, which comprises arranging a core material in a chamber box, placing the resin sheet or the laminate above the core material, heating and softening the resin sheet or the laminate, and reducing the pressure inside the chamber box to press the heat-softened resin sheet or the heat-softened laminate onto the core material to cover it. Vehicle interior materials, vehicle exterior materials, exterior covers for saddle-ride vehicles, housings for home appliances, decorative steel plates, decorative panels, housing equipment, or housings for information and communication devices, made using the molded articles described in 18.12. [Effects of the Invention]

[0007] According to the present invention, a resin sheet having high saturation and a deep appearance can be provided. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, the resin sheet, laminate, molded body, and method for manufacturing the molded body according to the present invention will be described. In this specification, "x to y" represents a numerical range of "x or more, y or less." When there are multiple lower limit values, such as "x or more," or multiple upper limit values, such as "y or less," for a single technical matter, any combination of upper and lower limit values ​​can be selected.

[0009] 1. Resin sheet A resin sheet according to one aspect of the present invention contains polypropylene containing smectite crystals and an interference pearl pigment. Smectic crystals are a metastable mesophase, and because the domain size of each crystal is small, polypropylene containing Smectic crystals has high transparency. By mixing an interference pearl pigment into a resin sheet based on such polypropylene, the color and brightness of the interference pearl pigment are fully exhibited, resulting in a clear, vivid appearance. Furthermore, the high transparency of polypropylene creates a sense of depth (three-dimensionality), and this, combined with the flip-flop properties (shadow effect) of the interference pearl pigment, allows for a resin sheet with depth and excellent design. Furthermore, by using such a resin sheet on the surface of a molded product, a molded product with the above-mentioned excellent design properties can be obtained. Each material used in the resin sheet will be described below.

[0010] (polypropylene) Polypropylene is a polymer containing at least propylene. Specific examples include homopolypropylene and copolymers of propylene and olefin. Homopolypropylene is particularly preferred for its heat resistance and hardness.

[0011] The polypropylene used in the resin sheet according to one embodiment of the present invention contains Smectic crystals. As described above, Smectic crystals are a metastable mesophase, and have excellent transparency due to the small domain size of each individual crystal. The α crystals contained in polypropylene sheets obtained by conventional methods have large crystal sizes, so molded products usually have an opaque, cloudy appearance. Even if a pearlescent pigment is added to such polypropylene, the cloudiness causes poor color development of the pearlescent pigment, lowering saturation and resulting in a flat design. However, by using Smectic crystals at least in part, high transparency can be achieved, eliminating these problems and achieving an excellent appearance. Furthermore, since the smectic crystals are in a metastable state, they soften into a sheet with a lower amount of heat than the α crystals, which are highly crystallized, and therefore have excellent moldability, making them preferable.

[0012] The crystalline structure of polypropylene may include, in addition to smectic crystals, other crystalline forms such as α crystals, β crystals, γ crystals, and amorphous portions. For example, 10% by mass or more, 20% by mass or more, 30% by mass or more, 50% by mass or more, 70% by mass or more, or 90% by mass or more of the polypropylene in the resin sheet may be smectic crystals. The specific method for confirming the crystal structure is as described in the Examples below.

[0013] In one embodiment of the present invention, the polypropylene preferably has an isotactic pentad fraction of 80 mol % or more. If the isotactic pentad fraction is 80 mol % or more, sufficient rigidity can be obtained when the resin sheet is made. The isotactic pentad fraction of the polypropylene is preferably 85 mol% or more, more preferably 90 mol% or more, and even more preferably 95 mol% or more, and is preferably 99 mol% or less, and even more preferably 98.5 mol% or less. When the isotactic pentad fraction is 80 mol % or more and 99 mol % or less, when the resin is made into a resin sheet, it is possible to obtain excellent rigidity and sufficient transparency. The isotactic pentad fraction is preferably 80 mol % or more and 99 mol % or less, more preferably 85 mol % or more and 99 mol % or less, and even more preferably 90 mol % or more and 98.5 mol % or less.

[0014] The isotactic pentad fraction is the isotactic fraction of pentad units (five consecutive propylene monomers isotactically bonded) in the molecular chain of the resin composition. This fraction can be measured by, for example, the method described in Macromolecules, Vol. 8 (1975), p. 687. 13 It can be measured by C-NMR. A specific method for measuring the isotactic pentad fraction is as described in the Examples below.

[0015] The copolymer of propylene and olefin may be a block copolymer or a random copolymer, or a mixture thereof, so long as the isotactic pentad fraction is 80 mol % or more (preferably 80 to 99 mol %). Examples of the olefin include ethylene, butylene, and cycloolefin.

[0016] In one embodiment of the present invention, the melt flow rate (hereinafter sometimes referred to as "MFR") of the polypropylene is preferably 0.5 g / 10 min or more, more preferably 1 g / 10 min or more, and even more preferably 2 g / 10 min or more. It is also preferably 10 g / 10 min or less, more preferably 8 g / 10 min or less, and even more preferably 6 g / 10 min or less. Within this range, excellent moldability into a film or sheet is achieved. The MFR of polypropylene is measured in accordance with JIS-K7210 at a measurement temperature of 230°C and a load of 2.16 kg.

[0017] In one embodiment of the present invention, the crystallization rate of polypropylene at 130°C is 2.5 min -1 It is preferable that the time is 2.0 min or less. -1More preferably, it is: Crystallization speed is 2.5 min -1 If it is less than this, deterioration of the design can be prevented. The lower limit is not particularly limited, but is usually 0.01 min -1 More than 0.05min -1 It is preferable that this is equal to or greater than this. The specific method for measuring the crystallization rate is as described in the Examples.

[0018] In one embodiment of the present invention, the resin sheet is preferably substantially free of or free of a nucleating agent. Even when a nucleating agent is contained, the amount is preferably small, for example, 1.0 mass % or less, 0.5 mass % or less, 0.1 mass % or less, 0.01 mass % or less, or 0.001 mass % or less of the resin composition, and for example, 1.0 mass % or less, 0.5 mass % or less, 0.1 mass % or less, 0.01 mass % or less, or 0.001 mass % or less relative to the amount of polypropylene. Examples of the nucleating agent include sorbitol-based crystal nucleating agents, and commercially available products include Gelall MD (Shin-Nihon Rikagaku Co., Ltd.) and Rikemaster FC-1 (Riken Vitamin Co., Ltd.).

[0019] In one embodiment, the crystallization rate of polypropylene without the addition of a nucleating agent is increased to 2.5 min -1 or less and then cooled at 80° C. / second or more to form the above-mentioned smectic crystals, a resin sheet having excellent transparency can be obtained.

[0020] The isotactic pentad fraction is 80 mol% or more and 99 mol% or less, and the crystallization rate of polypropylene is 2.5 min -1 In the following, in order to obtain a resin sheet having excellent transparency and gloss, it is usually necessary to form smectic crystals. By heating the resin sheet, the polypropylene in the resin sheet transforms to α crystal while maintaining the microstructure derived from the smectic crystal. However, the polypropylene in the molded product has an isotactic pentad fraction of 85 mol% or more and 99 mol% or less and the crystallization rate of the polypropylene is 2.5 min -1 If it is below this, it can be said to be derived from smectite crystals.

[0021] By calculating the scattering intensity distribution and long period using small-angle X-ray scattering analysis, it is possible to determine whether a resin sheet has been obtained by cooling at 80°C / sec or more. In other words, the above analysis makes it possible to determine whether a resin sheet has a microstructure derived from smectic crystals. The measurement is performed under the following conditions. The X-ray generator used is the ultraX 18HF (manufactured by Rigaku Corporation), and an imaging plate is used to detect scattering. ·Light source wavelength: 0.154nm Voltage / Current: 50kV / 250mA Irradiation time: 60 minutes Camera length: 1.085m -Sample thickness: Stack the sheets so that they are 1.5 to 2.0 mm. Stack the sheets so that the film formation (MD) direction is aligned. In order to shorten the measurement time, the sheets are stacked to a distance of 1.5 to 2.0 mm, but if the measurement time is extended, it is possible to measure with just one sheet without stacking the sheets.

[0022] In one embodiment of the present invention, the polypropylene preferably has an exothermic peak (also referred to as a "low-temperature exothermic peak") of 1 J / g or more, preferably 1.5 J / g or more, on the low-temperature side of the maximum endothermic peak in a curve (DSC curve) obtained by differential scanning calorimetry (DSC). The upper limit is not particularly limited, but is usually 10 J / g or less.

[0023] In one embodiment of the present invention, the polypropylene content in the resin sheet is usually 50% by mass or more, 60% by mass or more, or 70% by mass or more, and preferably 80% by mass or more or 90% by mass or more. Furthermore, it is usually 99.99% by mass or less, preferably 99.97% by mass or less or 99.95% by mass or less, and may be, for example, 99.7% by mass or less or 99.5% by mass or less.

[0024] (Interference pearl pigment) Interference pearlescent pigments are pigments in which the surface of a thin platelet-like substrate (scale-like fine particles) is coated with a metal oxide made of a colorless, high-refractive-index material such as titanium oxide, and are usually translucent. The layered arrangement of these scale-like fine particles causes multiple reflections of light, creating a metallic or pearl-like luster. In addition, because the coating layer has a certain thickness, reflected and transmitted light change, producing various interference colors, and the color changes depending on the viewing direction (angle) (flip-flop property).Interference pearl pigments are also sometimes called iridescent pearl pigments or polarized pearl pigments. Examples of flaky substrates include mica, alumina, glass (glass flakes), and silica.

[0025] Interference pearl pigments include, but are not limited to, titanium oxide coated mica, titanium oxide coated glass, and titanium oxide coated alumina. The interference pearl pigment may be used alone or in combination of two or more kinds.

[0026] Commercially available interference pearl pigments (trade names) include, for example, Lumina Royal Russet, Lumina Exterior Russet S5903D, Lumina Royal Copper, Lumina Royal Exterior Blue 6803H, Lumina Exterior Gold 2303D, Lumina Exterior Brass 2323D, Mearlin Exterior CFS Micro Russet 4503M, Mearlin Exterior CFS Bright Silver 1303Z, and Glacier Exterior Frost White S1303D (all manufactured by BASF Color & Effects Japan Co., Ltd.), Iriodin 7225 Ultra Rutile Blue Pearl, Iriodin 7219 Ultra Rutile Lilac Pearl, Xirallic Galaxy Blue, Colorstream T10-04 Lapis Sunlight, Miraval 5426 Magic Green, and Miraval 5421 Magic Copper (all manufactured by Merck Performance Materials LLC), and TWINCLE PEARL. Examples include SXA and TWINCLE PEARL YXB (both manufactured by Nihon Koken Kogyo Co., Ltd.).

[0027] In one embodiment of the present invention, the particle size of the interference pearl pigment is usually 1 to 200 μm, and preferably 5 to 100 μm. The particle size of the interference pearl pigment is measured using a particle size distribution meter. Specifically, in accordance with JIS Z 8828 (2013), a dynamic light scattering particle size distribution measuring device is used, in which a measurement sample in which particles are dispersed in a dispersion medium is placed in a sample cell, and this measurement sample is irradiated with laser light, and the particle size distribution is determined based on the frequency intensity distribution of the light scattered by the particles. It is preferable that 70% by number or more, 80% by number or more, or 90% by number or more of all particles fall within the above particle size range. In this specification, "a pigment composed mainly of particles with particle sizes of AA to BB μm" means that 90% by number or more of the particles contained in the pigment have particle sizes within the AA to BB μm range.

[0028] In one embodiment of the present invention, the content of the interference pearl pigment in the resin sheet is usually 0.01% by mass or more, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, for example, 0.3% by mass or more or 0.5% by mass or more, and usually 20% by mass or less, preferably 10% by mass or less.

[0029] In one embodiment of the present invention, the thickness of the resin sheet may be 5 μm or more, 10 μm or more, or 20 μm or more, and may be 3000 μm or less, 2000 μm or less, or 500 μm or less.

[0030] 2.Laminate The resin sheet according to one embodiment of the present invention may be formed into a laminate by laminating layers for imparting various functions or designs. Examples of such layers include a transparent layer and a colored layer, as described below.

[0031] (transparent layer, colored layer) A laminate according to one embodiment of the present invention comprises a first layer (transparent layer) containing polypropylene containing smectic crystals, and a second layer (interference pearl pigment-containing layer) made of the resin sheet described above.

[0032] As explained for the resin sheet, polypropylene containing smectite crystals has high transparency, so by laminating such a layer on the resin sheet (interference pearl pigment-containing layer) according to one embodiment of the present invention, a greater sense of depth (three-dimensional effect) is imparted to the entire laminate, making it possible to realize an appearance with greater depth and a more sophisticated design.

[0033] The polypropylene used in the first layer (transparent layer) is the same as the polypropylene used in the resin sheet according to one embodiment of the present invention. The thickness of the first layer (transparent layer) may be 5 μm or more, 7 μm or more, or 10 μm or more, and may be 300 μm or less, 250 μm or less, or 200 μm or less.

[0034] Furthermore, a layer (colored layer) containing a thermoplastic resin and a colorant may be laminated on the resin sheet (interference pearl pigment-containing layer) according to one embodiment of the present invention. By providing the colored layer, it is possible to prevent light transmission and improve reflectance, so that when viewed from the interference pearl pigment-containing layer side, it is possible to realize better color development of the interference pearl pigment with the colored layer as the background.

[0035] In one embodiment of the present invention, both the transparent layer and the colored layer may be provided to form a laminate of (colored layer / interference pearl pigment-containing layer / transparent layer), which makes it possible to simultaneously achieve the above-mentioned effects.

[0036] As the colorant used in the colored layer, known dyes, inorganic pigments, organic pigments, etc. can be used. Considering that the colorant may be blended in advance with the thermoplastic resin, it is preferable to use pigments such as inorganic pigments and organic pigments. Examples of dyes include anthraquinone dyes, phthalocyanine dyes, carbonium dyes, and indigoid dyes.

[0037] Examples of inorganic pigments include titanium oxide, zinc ferrite, yellow iron oxide, iron black, zinc sulfide, zinc oxide, carbon black, titanium yellow, ultramarine, cobalt blue, cobalt green, chromium oxide, iron oxide red, and composite oxide pigments.

[0038] Examples of organic pigments include benzimidazolone yellow, quinophthalone yellow, isoindolinone yellow, disazo yellow, monoazo yellow, condensed azo yellow, perinone orange, benzimidazolone orange, perylene red, quinacridone red, quinacridone magenta, diketopyrrolopyrrole, quinacridone violet, phthalocyanine blue, and phthalocyanine green.

[0039] The method for coloring the colored layer is not particularly limited, and for example, a method can be used in which the colorant is previously blended with a raw material resin, melt-kneaded, and then molded into a sheet. Alternatively, a method can be used in which the colorant is previously blended with a raw material resin or another resin, melt-kneaded, and then extruded to form a masterbatch, which can then be blended with the raw material resin and molded into a sheet.

[0040] In this way, by manufacturing the colored layer by adding a colorant to the raw resin in advance, there is no need to apply special treatment to the sheet surface, as is the case when manufacturing a colored layer by printing, which simplifies the manufacturing process and leads to cost reduction.

[0041] The color of the coloring is not particularly limited, and may be, for example, black, white, red, yellow, green, blue, etc. The laminate according to one aspect of the present invention can enhance the design according to any color.

[0042] The content of the colorant in the colored layer is usually 0.1% by mass or more, preferably 1% by mass or more, and more preferably 1.5% by mass or more, and usually 10% by mass or less, and preferably 7% by mass or less.

[0043] The thermoplastic resin is not particularly limited, but examples thereof include polypropylene and polyethylene, with polypropylene being preferred. When polypropylene is used as the resin component of the colored layer, it may be the same as or different from the polypropylene used in the first layer. The term "same" means that the various physical properties of the polypropylene described above are the same.

[0044] The content of the thermoplastic resin in the colored layer is usually 90% by mass or more, preferably 93% by mass or more, and usually 99.9% by mass or less, preferably 99% by mass or less, more preferably 98.5% by mass or less. The thickness of the colored layer may be 20 μm or more, 40 μm or more, or 50 μm or more, and may be 900 μm or less, 700 μm or less, or 500 μm or less.

[0045] In addition to the above-described layers, the resin sheet according to one embodiment of the present invention may also have layers for imparting various functions laminated thereto. Examples of such layers include an easy-adhesion layer, an undercoat layer, a metal layer, and a printed layer. These layers will be described below.

[0046] (Easy adhesion layer) The easy-adhesion layer preferably contains one or more resins selected from the group consisting of urethane-based resins, acrylic-based resins, polyolefin-based resins, and polyester-based resins. By providing such an easy-adhesion layer, even if the molded body described later is molded into a complex non-planar shape, the easy-adhesion layer can conform to the resin sheet to form a good layer structure, and cracks and peeling can be prevented.

[0047] The urethane resin is preferably a urethane resin obtained by reacting a diisocyanate, a high molecular weight polyol, and a chain extender. The high molecular weight polyol may be a polyether polyol or a polycarbonate polyol. Commercially available urethane resins include Hydran WLS-202 (manufactured by DIC Corporation). Examples of acrylic resins include Acrylit 8UA-366 (manufactured by Taisei Fine Chemical Co., Ltd.). Examples of polyolefin resins include Arrowbase DA-1010 (manufactured by Unitika Ltd.). Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate.

[0048] The adhesive layer may be formed from one of the above-mentioned materials alone or in combination of two or more thereof.

[0049] Among the urethane-based resins, acrylic-based resins, polyolefin-based resins and polyester-based resins contained in the easy-adhesion layer, urethane-based resins are preferred in consideration of adhesion to the metal layer and printed layer described below and formability.

[0050] In addition, when the easy-adhesion layer contains a polypropylene-based resin, the polypropylene-based resin contained in the easy-adhesion layer is usually different from the polypropylene that may be contained in the resin sheet or the molded body.

[0051] The easy-adhesion layer may be a single layer or may have a laminated structure of two or more layers.

[0052] The thickness of the easy-adhesion layer may be 35 nm or more and 3000 nm or less, 50 nm or more and 2000 nm or less, or 50 nm or more and 1000 nm or less. The thickness of the easy-adhesion layer may be 35 nm or more, or 50 nm or more, or may be 3000 nm or less, 2000 nm or less, or 1000 nm or less.

[0053] The easy-adhesion layer can be formed, for example, by applying the above-mentioned resin with a gravure coater, kiss coater, bar coater, or the like, and drying it at 40 to 100° C. for 10 seconds to 10 minutes.

[0054] On the adhesive layer, various coatings such as ink, hard coat, anti-reflection coat, and heat-shielding coat can be laminated. In addition, in the resin sheet, another easy-adhesion layer (second easy-adhesion layer) may be provided on the surface opposite to the above easy-adhesion layer (first easy-adhesion layer). In this way, functionality such as surface treatment or hard coating can be imparted to the polyolefin resin layer that forms the surface of the molded article.

[0055] (undercoat layer) The undercoat layer is a layer that can bond the easy-adhesion layer and the metal layer together. By providing the undercoat layer, even when stress is applied during thermoforming, countless extremely fine cracks can be generated in the metal layer, thereby eliminating or reducing the occurrence of the rainbow phenomenon. Examples of materials for forming the undercoat layer include urethane resin, acrylic resin, polyolefin, and polyester.

[0056] From the viewpoint of whitening resistance during molding (how little whitening occurs) and adhesion to the metal layer, an acrylic resin is preferred as the material for forming the undercoat layer, and for example, "DA-105" manufactured by Arakawa Chemical Industries, Ltd. can be used.

[0057] The above materials may be used alone or in combination of two or more.

[0058] The undercoat layer may be formed by combining the resin component (main component) with a curing agent. Examples of the curing agent include aziridine compounds, blocked isocyanate compounds, epoxy compounds, oxazoline compounds, and carbodiimide compounds. For example, "CL102H" manufactured by Arakawa Chemical Industries, Ltd. can be used.

[0059] When a curing agent is used, the content ratio of the main agent to the curing agent in the undercoat layer is, for example, 35:4 to 35:40, preferably 35:4 to 35:32, more preferably 35:12 to 35:32, in terms of the mass ratio of solids. Alternatively, it may be 35:12 to 35:20. When the ratio of the curing agent to the base resin is 4:35 or more, the curing reaction proceeds smoothly and whitening resistance can be maintained. When the ratio is 40 or less, the undercoat layer has good extensibility and cracking during molding can be suppressed.

[0060] The undercoat layer can be formed, for example, by applying the above-mentioned material using a gravure coater, kiss coater, or bar coater, drying it at 50 to 100°C for 10 seconds to 10 minutes, and aging it at 40 to 100°C for 10 to 200 hours.

[0061] The thickness of the undercoat layer may be 0.05 μm to 50 μm, 0.1 μm to 10 μm, or 0.5 μm to 5 μm. The thickness of the undercoat layer may be 0.05 μm or more, 0.1 μm or more, or 0.5 μm or more, and may be 50 μm or less, 10 μm or less, or 5 μm or less.

[0062] (metal layer) The metal layer is a layer containing a metal or a metal oxide. The metal that forms the metal layer is not particularly limited as long as it is a metal that can impart a metallic design to the laminate, and examples thereof include tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, and zinc, and an alloy containing at least one of these may also be used. Among the above, indium and aluminum are preferred because they are particularly excellent in extensibility and color tone. When the metal layer has excellent extensibility, cracks are less likely to occur when the laminate is three-dimensionally molded.

[0063] The method for forming the metal layer is not particularly limited, but from the viewpoint of imparting a high-quality, luxurious metallic design to the laminate, for example, a vapor deposition method using the above-mentioned metals, such as vacuum vapor deposition, sputtering, or ion plating, can be used. In particular, the vacuum vapor deposition method is low cost and can reduce damage to the substrate. The conditions for the vacuum vapor deposition method may be appropriately set depending on the melting temperature or evaporation temperature of the metal used.

[0064] In addition to the above methods, a method of applying a paste containing the above metal or metal oxide, a plating method using the above metal, etc. can also be used.

[0065] The thickness of the metal layer may be 5 nm or more and 80 nm or less. If it is 5 nm or more, the desired metallic luster can be obtained without any problems, and if it is 80 nm or less, cracks are less likely to occur.

[0066] (Printing layer) The shape of the printed layer is not particularly limited, but may be a variety of shapes such as a solid pattern, a carbon pattern, or a wood grain pattern. Common printing methods that can be used include screen printing, offset printing, gravure printing, roll coating, spray coating, etc. Screen printing, in particular, allows for a thick ink film, making it less likely to crack when molding into complex shapes. For example, in the case of screen printing, inks that have excellent elongation during molding are preferred, and examples thereof include "FM3107 High Density White" and "SIM3207 High Density White" manufactured by Jujo Chemical Co., Ltd., but are not limited to these.

[0067] 3. Manufacturing method of resin sheet (or laminate) The method for producing the resin sheet (or laminate) according to one embodiment of the present invention is not particularly limited, and examples thereof include an extrusion method (co-extrusion method). The extrusion method involves cooling the melt of the resin sheet (hereinafter referred to as the molten resin), and the cooling is preferably carried out at a cooling rate of 80°C / sec or more until the internal temperature of the resin sheet falls below the crystallization temperature. This allows the crystalline structure of the polypropylene contained in the resin sheet to become the Smectic crystal. The cooling rate is more preferably 90°C / sec or more, and even more preferably 150°C / sec or more. The specific production method will be described in detail in the Examples.

[0068] 4. Molded body The resin sheet or laminate according to one aspect of the present invention can be used to form a molded article. The molded article is produced by molding the resin sheet or laminate by a method such as thermoforming. In one embodiment, the molded article is given a shape including a three-dimensional curved surface.

[0069] 5. Manufacturing method of molded body A method for producing a molded article according to one aspect of the present invention includes molding a resin sheet or laminate. Examples of the molding method include in-mold molding, insert molding, in-mold insert molding, and cover molding.

[0070] In-mold molding is a method in which a laminate is placed in a mold and molded into a desired shape by the pressure of a molding resin supplied into the mold to obtain a molded product. In-mold molding is preferably performed by placing the laminate in a mold and supplying molding resin to integrate the laminate.

[0071] Insert molding is a method in which a molded body is obtained by preforming a shaped body to be placed in a mold and then filling that shape with molding resin. It is possible to form more complex shapes. Insert molding can be performed by shaping the laminate to fit a mold, placing the shaped laminate in the mold, and supplying molding resin to integrate the laminate. Shaping (pre-shaping) to fit a mold can be performed by vacuum forming, pressure forming, vacuum pressure forming, press forming, plug assist forming, or the like.

[0072] The molding resin may be a moldable thermoplastic resin. Specific examples include, but are not limited to, polypropylene, polyethylene, polycarbonate, acetylene-styrene-butadiene copolymer, and acrylic polymer. Inorganic fillers such as fiber and talc may be added to the thermoplastic resin. The supply is preferably carried out by injection, and the pressure is preferably 5 MPa or more and 120 MPa or less, and the mold temperature is preferably 20°C or more and 90°C or less.

[0073] Another type of insert molding is a method in which a resin sheet is pre-shaped in a mold used for injection molding. Specifically, the process involves heating a resin sheet, placing it on the cavity surface of a mold, and shaping the resin sheet to match the shape of the mold, and supplying molding resin toward the shaped resin sheet to integrate the molding resin and the shaped resin sheet. As a method for pre-shaping a resin sheet, for example, the resin sheet is preheated with a heater or the like, the heated resin sheet is placed on the cavity surface of a mold for injection molding, and the inside of the cavity is suctioned, so that the resin sheet can be shaped to match the internal shape of the mold. Thereafter, the molded resin sheet is left in place in the cavity, and a molding resin is filled to obtain a molded body. According to this method, a molded body having a more complicated shape can be formed by a simpler method.

[0074] In coating molding, a core material is placed inside a chamber box, a laminate is placed above the core material, the pressure inside the chamber box is reduced, the laminate is heated and softened, the laminate is brought into contact with the top surface of the core material, and the heated and softened laminate is pressed against the core material to coat it. After heat softening, the laminate may be brought into contact with the upper surface of the core material. Pressing can be carried out in a chamber box by applying pressure to the side of the laminate opposite to the core material while keeping the pressure reduced on the side of the laminate that contacts the core material.

[0075] The core material may be convex or concave, and examples thereof include resins, metals, ceramics, etc., each having a three-dimensional curved surface. The resin is not particularly limited, and examples thereof include the same thermoplastic resins as those used in the above-mentioned molding.

[0076] For the covering molding, for example, a chamber box consisting of two separable molding chambers, an upper chamber and a lower chamber, can be used. First, the core material is placed on the table in the lower molding chamber and set in place. The laminate, which is the object to be molded, is fixed to the top surface of the lower molding chamber with a clamp. At this time, the interior of the upper and lower molding chambers is at atmospheric pressure. Next, the upper molding chamber is lowered, the upper and lower molding chambers are joined, and the inside of the chamber box is closed. Both the upper and lower molding chambers are brought from atmospheric pressure to a vacuum suction state by the vacuum tank. After creating a vacuum inside the upper and lower molding chambers, the heater is turned on to heat the laminate. Next, while the upper and lower molding chambers are still in a vacuum state, the table inside the lower molding chamber is raised. Next, the vacuum in the upper molding chamber is released and atmospheric pressure is introduced, pressing the laminate onto the core material and overlaying (molding). It is also possible to apply compressed air to the upper molding chamber to apply greater force to adhere the laminate to the core material. After the overlaying is completed, the heater is turned off, the vacuum in the lower molding chamber is released to return it to atmospheric pressure, the upper molding chamber is raised, and the product coated with the laminate as a skin material is removed.

[0077] 6. Uses of the molded body The uses of the molded article described above are not particularly limited, and it can be used for various uses. In one embodiment, the molded article can be used as an exterior part for a saddle-ride type vehicle or an exterior part for a four-wheel vehicle. The molded article can also be used as an interior material, an exterior material for a vehicle, a housing for a home appliance, a decorative steel plate, a decorative panel, a housing for a home appliance, a housing for an information and communication device, etc. [Example]

[0078] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0079] Example 1 The following materials were prepared for producing the resin sheet. Polypropylene resin: Homopolypropylene (Prime Polypro F-133A manufactured by Prime Polymer Co., Ltd., MFR: 2.8 g / 10 min, hereinafter referred to as "PP1") Luster pigment: Interference pearl pigment (titanium oxide-coated mica, "Lumina Exterior Russet S5903D" manufactured by BASF Color & Effects Japan Co., Ltd., red interference color, pigment mainly consisting of particles with a particle diameter of 6 to 43 μm, hereinafter referred to as "Interference Pearl 1")

[0080] [Production and evaluation of resin sheets] PP1 and Interference Pearl 1 were melt-kneaded in the amounts shown in Table 1 to obtain a pellet-shaped melt-kneaded material. The resulting melt-kneaded material was extrusion-molded at a molding temperature of 230°C using a 20mm diameter cast molding machine (Dr. Collin's "TEACH-LINE Extruder E20T") to produce a 40µm thick resin sheet. The resulting resin sheet was then sandwiched between stainless steel plates and heated to 200°C using a press (Tokyo Jitsugyo Co., Ltd.'s "TJ-S5030SM"), and then immersed in 10°C water (cooling rate: 95°C / sec) to obtain a resin sheet (the above manufacturing method will be referred to as "Manufacturing Method 1" hereinafter).

[0081] The resin sheet obtained was subjected to the following evaluations, and the results are shown in Table 1. (isotactic pendant fraction) About PP1 13 The isotactic pendant fraction was measured by evaluating the C-NMR spectrum. Specifically, the isotactic pendant fraction was measured according to the peak assignments proposed by A. Zambelli et al. in "Macromolecules, 8, 687 (1975)" using the following equipment, conditions, and calculation formula. ·Equipment / Conditions Equipment: JNM-EX400 model manufactured by JEOL Ltd. 13 C-NMR device Method: Proton complete decoupling method Concentration: 220mg / ml Solvent: 90:10 (volume ratio) mixture of 1,2,4-trichlorobenzene and heavy benzene Temperature: 130℃ Pulse width: 45° Pulse repetition time: 4 seconds Accumulation: 10,000 times ·Calculation formula Isotactic pendant fraction [mmmm] = m / S × 100 S: signal intensity of the side chain methyl carbon atoms of all propylene units m: Mesopentad chain: 21.7-22.5 ppm

[0082] (crystallization rate) The crystallization rate of PP1 was measured using a differential scanning calorimeter (DSC) (product name "Diamond DSC", manufactured by PerkinElmer). Specifically, PP1 was heated from 50°C to 230°C at 10°C / min, held at 230°C for 5 minutes, cooled from 230°C to 130°C at 80°C / min, and then held at 130°C for crystallization. Measurement of the change in heat quantity was started when the temperature reached 130°C, and a DSC curve was obtained. The crystallization rate was calculated from the obtained DSC curve using the following steps (i) to (iv). (i) The baseline was determined as a linear approximation of the change in calorific value from a point 10 times the time from the start of measurement to the peak top to a point 20 times the time. (ii) The intersection points of the tangent line having a slope at the inflection point of the peak and the baseline were determined, and the crystallization start and end times were calculated. (iii) The time from the obtained crystallization start time to the peak top was measured as the crystallization time. (iv) The crystallization rate was calculated from the reciprocal of the obtained crystallization time.

[0083] (crystalline form) The crystalline form of the polypropylene resin was confirmed by wide-angle X-ray diffraction (WAXD) using the method used by T. Konishi et al. (Macromolecules, 38, 8749, 2005). The analysis involved separating the peaks of the amorphous, mesophase, and crystalline phases from the X-ray diffraction profile, and determining the abundance ratio from the peak area assigned to each phase.

[0084] (Saturation) Using a spectrophotometer (Konica Minolta Japan, Inc. "CM-M6"), L was measured under the conditions of D65 light source, 10 degree field of view, illumination angle 45°, and light receiving angle 15°. * a * b * The color system is measured and the saturation is C * The values ​​were measured. Saturation C * is {(a * ) 2 +(b * ) 2} 1 / 2 was calculated.

[0085] (Depth of design) The depth of the design of the resin sheet was visually evaluated according to the following criteria. A: The design has depth and can be observed in three dimensions. B: The design lacks depth and appears flat. C: The sheet is cloudy and the design lacks depth.

[0086] (flip-flop) The flip-flop property of the resin sheet was evaluated visually according to the following criteria. A: It has a flip-flop quality and gives a sense of shadow. B: There is no flip-flop effect and it feels flat.

[0087] Example 2 A resin sheet was produced and evaluated in the same manner as in Example 1, except that the glossy pigment was changed to an interference pearl pigment (titanium oxide-coated mica, "Iriodin 7225" manufactured by Merck Performance Materials LLC, a blue interference color pigment mainly composed of particles with a particle diameter of 10 to 60 μm, hereinafter referred to as "Interference Pearl 2"). The results are shown in Table 1.

[0088] Example 3 A resin sheet was produced and evaluated in the same manner as in Example 1, except that the glossy pigment was changed to an interference pearl pigment (titanium oxide-coated mica, "Lumina Royal Exterior Copper 3903H" manufactured by BASF Color & Effects Japan, Ltd., a pigment mainly consisting of particles with a particle diameter of 6 to 43 μm, reddish-copper interference color, hereinafter referred to as "Interference Pearl 3"). The results are shown in Table 1.

[0089] Example 4 A resin sheet was produced and evaluated in the same manner as in Example 3, except that the blending amount of the glossy pigment was changed to 1.0 mass %. The results are shown in Table 1.

[0090] Example 5 A resin sheet was produced and evaluated in the same manner as in Example 1, except that the glossy pigment was changed to an interference pearl pigment (titanium oxide-coated alumina, "Xirallic T60-23 SW Galaxy Blue" manufactured by Merck Performance Materials LLC, a pigment mainly consisting of particles with a particle diameter of 5 to 30 μm, blue interference color, hereinafter referred to as "Interference Pearl 4"). The results are shown in Table 1.

[0091] Comparative Example 1 A resin sheet was produced and evaluated in the same manner as in Example 1, except that the resin sheet obtained using a cast molding machine (Dr. Collin's "TEACH-LINE Extruder E20T") was used as is, without heating using a press or immersing in 10°C water (cooling rate: 45°C / sec; this resin sheet production method will be referred to as "Production Method 2" hereinafter). The results are shown in Table 1.

[0092] Comparative Example 2 A resin sheet was produced and evaluated in the same manner as in Example 2, except that the resin sheet was produced by Production Method 2. The results are shown in Table 1.

[0093] Comparative Example 3 A resin sheet was produced and evaluated in the same manner as in Example 3, except that the resin sheet was produced by Production Method 2. The results are shown in Table 1.

[0094] Comparative Example 4 A resin sheet was produced and evaluated in the same manner as in Example 4, except that the resin sheet was produced by Production Method 2. The results are shown in Table 1.

[0095] Comparative Example 5 A resin sheet was produced and evaluated in the same manner as in Example 5, except that the resin sheet was produced by Production Method 2. The results are shown in Table 1.

[0096] Comparative Example 6 A resin sheet was produced and evaluated in the same manner as in Example 1, except that the glossy pigment was changed to an aluminum pigment ("Silveeds M100-BP" manufactured by Asahi Kasei Corporation, a pigment mainly consisting of particles with a particle diameter of 3 to 30 μm, a metallic pigment containing 90 mass % aluminum and 10 mass % polyethylene glycol, hereinafter referred to as "Aluminum 1"). The results are shown in Table 1. In Comparative Example 6, a resin sheet was produced by Manufacturing Method 1, but because aluminum 1 was opaque, the transparency of the entire resin sheet was reduced, and a sense of depth or three-dimensionality was not obtained, resulting in a design lacking in profundity.

[0097] Comparative Example 7 A resin sheet was produced and evaluated in the same manner as in Comparative Example 6, except that the resin sheet was produced by Production Method 2. The results are shown in Table 1.

[0098] [Table 1] [Industrial Applicability]

[0099] Molded articles obtained from the laminate of the present invention can be used in a wide variety of applications, for example, as decorative sheets that replace painting on housings in a wide range of fields such as transportation equipment (automobiles, motorcycles, etc.), housing equipment, building materials, and home appliances.

Claims

1. A resin sheet comprising homopolypropylene containing smectic crystals and an interference pearl pigment.

2. The resin sheet according to claim 1, wherein the homopolypropylene has an isotactic pentad fraction of 85 mol% to 99 mol%.

3. The crystallization rate of the homopolypropylene at 130°C is 2.5 min －１ The resin sheet according to claim 1 or 2, wherein:

4. The resin sheet according to any one of claims 1 to 3, wherein the homopolypropylene has an exothermic peak of 1 J / g or more on the low-temperature side of a maximum endothermic peak in a curve obtained by differential scanning calorimetry.

5. The resin sheet according to any one of claims 1 to 4, wherein the interference pearl pigment is one or more selected from the group consisting of titanium oxide-coated mica, titanium oxide-coated glass, and titanium oxide-coated alumina.

6. 6. The resin sheet according to claim 1, wherein the content of the interference pearl pigment is 0.01% by mass or more and 20% by mass or less.

7. A laminate comprising a first layer containing polypropylene containing smectic crystals and a second layer made of the resin sheet according to any one of claims 1 to 6.

8. The laminate of claim 7 , further comprising a third layer on the side of the second layer opposite the first layer, the third layer comprising a thermoplastic resin and a colorant.

9. A laminate comprising the resin sheet according to any one of claims 1 to 6 and an easy-adhesion layer.

10. The laminate according to claim 9 , wherein the easy-adhesion layer contains one or more resins selected from the group consisting of urethane, acrylic, polyolefin, and polyester.

11. The laminate according to claim 9 or 10, further comprising a printed layer on a surface of the easy-adhesion layer opposite to the resin sheet.

12. A molded article produced using the resin sheet according to any one of claims 1 to 6 or the laminate according to any one of claims 7 to 11.

13. A method for producing a molded article, comprising molding the resin sheet according to any one of claims 1 to 6 or the laminate according to any one of claims 7 to 11 to obtain a molded article.

14. Placing the resin sheet or the laminate on a mold; and By supplying a molding resin toward the resin sheet or the laminate, the resin sheet or the laminate is shaped to fit a mold, and the molding resin and the resin sheet or the laminate are integrated. The method for producing the molded article according to claim 13, comprising:

15. Shaping the resin sheet or the laminate to fit a mold; and The molding resin is supplied toward the shaped resin sheet or the shaped laminate, thereby integrating the molding resin with the shaped resin sheet or the shaped laminate. The method for producing the molded article according to claim 13, comprising:

16. The resin sheet or the laminate is heated and placed on a cavity surface of a mold, and the resin sheet or the laminate is shaped to match the shape of the mold; and The molding resin is supplied toward the shaped resin sheet or the shaped laminate, thereby integrating the molding resin with the shaped resin sheet or the shaped laminate. The method for producing the molded article according to claim 13, comprising:

17. 14. A method for manufacturing a molded body according to claim 13, comprising disposing a core material in a chamber box, placing the resin sheet or the laminate above the core material, heating and softening the resin sheet or the laminate, and reducing the pressure inside the chamber box to press the heat-softened resin sheet or the heat-softened laminate onto the core material to cover it.

18. A vehicle interior material, a vehicle exterior material, an exterior cover for a saddle-ride type vehicle, a housing for a home appliance, a decorative steel plate, a decorative panel, a housing equipment, or a housing for an information and communication device, produced using the molded article according to claim 12.

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