Master batch and manufacturing method thereof

Abstract

To provide a technique capable of contributing to manufacturing a transparent resin molding excellent in optical characteristics including a polyolefin resin.SOLUTION: A master batch for manufacturing a transparent resin molding includes: a resin having a polyolefin resin at a proportion of 90 to 100 mass%; and a nucleating agent. The master batch has color coordinates L, a and b of Hunter 1948 Lab color space within ranges 40≤L≤60, -2≤a≤+2 and -3≤b≤+3, respectively. Alternatively, the master batch includes: a resin having a polyolefin resin at a proportion of 90 to 100 mass% and a nucleating agent, and when crystallized at a cooling rate of -10°C / min in a differential scan calorimetry, shows a crystallization temperature within a range of 130 to 140°C, a half-width of crystallization energy within a range of 1.0 to 5.5°C, and a crystallization enthalpy within a range of 115 to 130 mJ / mg.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a masterbatch.

Background Art

[0002] Molded articles made of resin are used in various fields. For example, a laminated film composed of a plurality of resin layers can exhibit performance and functions that cannot be achieved by a single-layer film, and therefore, it is used in a wide range of fields including cosmetic sheets, packaging materials, and electronic components.

[0003] Cosmetic sheets are used, for example, as building materials for interior and exterior decoration of buildings or as surface materials for furniture or home appliances. Cosmetic sheets are used as decorative boards, for example, by being bonded to substrates such as wood boards, inorganic boards, and metal plates.

[0004] As cosmetic sheets, those using polyvinyl chloride were generally used as described in Patent Document 1. However, such cosmetic sheets generate toxic gases during incineration. For this reason, as described in Patent Documents 2 to 4, many cosmetic sheets using polyolefin-based resins instead of polyvinyl chloride have been proposed.

[0005] Cosmetic sheets using polyolefin-based resins instead of polyvinyl chloride do not generate toxic gases derived from chlorine during incineration. However, since these cosmetic sheets use general polypropylene sheets or soft polypropylene sheets, their scratch resistance is much inferior to that of cosmetic sheets using polyvinyl chloride.

[0006] When using highly crystalline polypropylene having a high initial flexural modulus as the polyolefin-based resin, excellent scratch resistance can be achieved. However, cosmetic sheets using such highly crystalline polypropylene may break or crack at the outer periphery when subjected to bending processes such as V-groove bending.

[0007] Also, usually, since the spherulite size of polypropylene resin is larger than the wavelength of visible light (400 to 750 nm), it is milky white. In a decorative sheet, the transparent resin layer is required to protect the pattern layer and the base sheet provided in the lower layer, and not to prevent the patterns, designs, etc. printed thereon from being visually recognized from the outermost surface of the decorative sheet.

[0008] In response to these problems, Patent Document 5 describes adding a nano-sized nucleating agent to a crystalline polypropylene resin. Further, Patent Document 5 describes encapsulating a nucleating agent in an outer membrane made of phospholipid by a supercritical reverse phase evaporation method, and adding the obtained vesicles to a crystalline polypropylene resin. The vesicles obtained by the supercritical reverse phase evaporation method are extremely small in size. Therefore, when the above nucleating agent or vesicles are added to a crystalline polypropylene resin, the size of the spherulites can be made extremely small, and furthermore, the crystallinity of the crystalline part can be dramatically improved. As a result, high transparency can be achieved, and excellent scratch resistance and post-processing resistance can be achieved.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0010] The object of the present invention is to provide a technique that includes a polyolefin resin and can contribute to the production of a transparent resin molded article having excellent optical properties.

Means for Solving the Problems

[0011] According to one aspect of the present invention, there is provided a masterbatch for producing a transparent resin molded article, which includes a resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass and a nucleating agent, and the color coordinates L, a, and b in the Hunter 1948 Lab color space are respectively in the ranges represented by 40 ≦ L ≦ 60, -2 ≦ a ≦ +2, and -3 ≦ b ≦ +3.

[0012] According to another aspect of the present invention, there is provided a masterbatch for producing a transparent resin molded article, which includes a resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass and a nucleating agent, and when crystallization is caused with a temperature decrease rate of -10 °C / min in differential scanning calorimetry, it shows a crystallization temperature in the range of 130 to 140 °C, a half-width of crystallization energy in the range of 1.0 to 5.5 °C, and a crystallization enthalpy in the range of 115 to 130 mJ / mg.

[0013] According to still another aspect of the present invention, there is provided a transparent resin including the masterbatch according to any one of the above aspects and a raw material resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass.

[0014] According to still another aspect of the present invention, there is provided a transparent resin according to the above aspect, wherein the polyolefin resin included in the masterbatch and the raw material resin is a highly crystalline polypropylene resin having an isotactic pentad fraction (mmmm fraction) of 95% or more.

[0015] According to still another aspect of the present invention, there is provided a transparent resin molded article made of the transparent resin according to any one of the above aspects.

[0016] According to still another aspect of the present invention, there is provided a transparent resin layer made of the transparent resin according to any one of the above aspects.

[0017] According to still another aspect of the present invention, there is provided a transparent resin layer according to the above aspect, having a haze value of 15% or less, and the color coordinates L, a, and b in the Hunter 1948 Lab color space being within the ranges represented by 40 ≦ L ≦ 50, -1 ≦ a ≦ +1, and -2 ≦ b ≦ +2, respectively.

[0018] According to still another aspect of the present invention, there is provided a transparent resin layer according to any of the above aspects, which exhibits a crystallization temperature within the range of 130 to 140 °C, a half-width of crystallization energy within the range of 1.0 to 5.5 °C, and a crystallization enthalpy within the range of 115 to 130 mJ / mg when crystallization is caused with a temperature-lowering rate of -10 °C / min in differential scanning calorimetry.

[0019] According to still another aspect of the present invention, there is provided a transparent resin layer according to any of the above aspects, having a tensile modulus within the range of 800 to 2000 MPa and a tensile elongation at break of 200% or more.

[0020] According to still another aspect of the present invention, there is provided a transparent resin layer according to any of the above aspects, having a thickness within the range of 20 to 250 μm.

[0021] According to still another aspect of the present invention, there is provided a laminate including a transparent resin layer according to any of the above aspects and one or more other layers.

[0022] According to still another aspect of the present invention, there is provided a laminate according to the above aspect, which is a decorative sheet.

[0023] According to still another aspect of the present invention, there is provided a method for producing a masterbatch, including kneading a raw material containing a resin in which the proportion of a polyolefin resin is within the range of 90 to 100% by mass and a nucleating agent in the presence of a supercritical fluid, and setting the amount of the supercritical fluid within the range of 5 to 20 parts by mass with respect to 100 parts by mass of the raw material.

[0024] According to still another aspect of the present invention, there is provided a method for producing a masterbatch, which comprises feeding the raw material into a kneading extruder and supplying the supercritical fluid to the kneading extruder into which the raw material has been fed, or supplying a fluid to the kneading extruder into which the raw material has been fed to generate the supercritical fluid from the fluid in the kneading extruder.

[0025] According to still another aspect of the present invention, there is provided a method for producing a masterbatch, wherein the kneading extruder has an inlet for feeding the raw material, an outlet for discharging a kneaded product obtained by kneading the raw material, and a supply port provided between the inlet and the outlet, and the supercritical fluid or the fluid is supplied to the kneading extruder through the supply port.

[0026] According to still another aspect of the present invention, there is provided a method for producing a masterbatch, wherein the supercritical fluid is composed of carbon dioxide, which relates to any one of the above aspects.

[0027] According to still another aspect of the present invention, there is provided a method for producing a transparent resin, which comprises kneading a masterbatch produced by the production method according to any one of the above aspects and a raw material resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass.

[0028] According to still another aspect of the present invention, there is provided a method for producing a transparent resin molded article, which comprises producing a transparent resin by the production method according to the above aspect and molding the transparent resin to obtain a molded article.

[0029] According to still another aspect of the present invention, there is provided a method for producing a transparent resin layer, which comprises producing a transparent resin by the production method according to the above aspect and molding the transparent resin to obtain a resin layer.

[0030] According to still another aspect of the present invention, there is provided a method for producing a laminate, which comprises producing a transparent resin by the production method according to the above aspect and molding the transparent resin to obtain a transparent resin layer.

Advantages of the Invention

[0031] According to the present invention, there is provided a technique that includes a polyolefin resin and can contribute to the production of a transparent resin molded article having excellent optical properties.

Brief Description of the Drawings

[0032]

Figure 1

Modes for Carrying Out the Invention

[0033] Embodiments of the present invention will be described below. The embodiments described below are more specific forms of any of the above aspects. The matters described below can be incorporated into each of the above aspects alone or in combination.

[0034] Also, the embodiments shown below are examples of configurations for embodying the technical idea of the present invention, and the technical idea of the present invention is not limited by the materials, shapes, structures, etc. of the following constituent members. Various modifications can be made to the technical idea of the present invention within the technical scope defined by the claims described in the claims.

[0035] Note that the drawings referred to below are schematic, and the relationship between dimensions in one direction and dimensions in another direction, and the relationship between the dimensions of one member and the dimensions of other members, etc. may be different from the actual ones.

[0036] <1> Masterbatch The masterbatch according to an embodiment of the present invention is a masterbatch for producing a transparent resin molded article. A transparent resin molded article such as a transparent resin layer is produced from a transparent resin obtained by kneading this masterbatch and a raw material resin described later.

[0037] This masterbatch contains a resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass and a nucleating agent.

[0038] Examples of polyolefin resins include polypropylene; polyethylene; polybutene; homopolymers of α-olefins (e.g., propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, and 12-ethyl-1-tetradecene) or copolymers of two or more of them; and copolymers of ethylene or α-olefin with other monomers such as ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate copolymer.

[0039] The polyolefin resin is preferably a crystalline resin. Also, the polyolefin resin is, for example, a polypropylene resin. The polyolefin resin is preferably a crystalline polypropylene resin.

[0040] The crystalline polypropylene resin may be a homopolymer, a copolymer such as a random copolymer or a block copolymer, or a mixture thereof. The polypropylene contained in the crystalline polypropylene resin may be isotactic polypropylene, syndiotactic polypropylene, or a combination thereof. Further, in the crystalline polypropylene resin, the polypropylene may have pentad fractions that are equal to each other, or a combination of polypropylenes with different pentad fractions. The crystalline polypropylene resin is preferably a highly crystalline homopolypropylene resin that is a homopolymer of propylene having an isotactic pentad fraction (mmmm fraction) of 95% or more, more preferably 96% or more.

[0041] Here, the isotactic pentad fraction (mmmm fraction) is calculated from a numerical value (electromagnetic wave absorption rate) obtained by resonating the crystalline polypropylene resin at a predetermined resonance frequency by 13C-NMR measurement (nuclear magnetic resonance measurement) using carbon C (nuclide) with a mass number of 13. The pentad fraction is related to the atomic arrangement, electron structure, and fine structure of the resin. The isotactic pentad fraction of the polypropylene resin is the ratio of a specific sequence consisting of five propylene units, i.e., a sequence in which all propylene units have the same configuration, determined by 13C-NMR measurement, and is used as a measure of crystallinity or stereoregularity. And such an isotactic pentad fraction is one of the important factors that mainly determine the scratch resistance of the surface. Basically, the higher the isotactic pentad fraction, the higher the crystallinity of the sheet, and thus the better the scratch resistance.

[0042] The masterbatch can contain other resins in addition to the polyolefin resin. Any other resin may be used as long as it shows high compatibility with the polyolefin resin. However, the proportion of the polyolefin resin in the resins contained in the masterbatch shall be in the range of 90 to 100% by mass as described above, preferably in the range of 95 to 100% by mass.

[0043] The nucleating agent plays a role in promoting the formation of crystal nuclei during the crystallization of the resin, or itself serves as a crystal nucleus.

[0044] As the nucleating agent, there are a melting-type nucleating agent that melts during kneading with the resin and dissolves in the resin, and precipitates during the cooling process to form crystal nuclei, and a non-melting-type nucleating agent that serves as a crystal nucleus without undergoing the above-mentioned melting and precipitation. Examples of the nucleating agent include metal phosphate esters, metal benzoates, metal pimelates, metal rosins, benzylidene sorbitol, quinacridone, cyanine blue, and talc.

[0045] When using a non-melting-type nucleating agent, it is preferable to subject the nucleating agent to the nanosizing treatment described later. From the viewpoint of non-coloring property, it is preferable to use a metal phosphate ester, a metal benzoate, a metal pimelate, or a metal rosin as the non-melting-type nucleating agent. Also, a colored nucleating agent, for example, quinacridone, cyanine blue, or talc, may be used as the non-melting-type nucleating agent. When using a non-melting-type nucleating agent, only the non-melting-type nucleating agent may be used as the nucleating agent, or a non-melting-type nucleating agent and a melting-type nucleating agent such as benzylidene sorbitol may be used in combination.

[0046] The amount of the nucleating agent is preferably in the range of 0.01 to 5 parts by mass, more preferably in the range of 0.05 to 1 part by mass, based on 100 parts by mass of the resin.

[0047] The nucleating agent may be subjected to nanosizing treatment. According to the nanosizing treatment, for example, nucleating agent particles with an average particle diameter of 375 nm or less can be obtained. Here, the average particle diameter is the median diameter obtained by the static light scattering method.

[0048] As the nanosizing treatment, for example, a solid-phase method in which the nucleating agent is mainly mechanically pulverized to obtain nano-sized particles, a liquid-phase method in which crystallization or synthesis of nano-sized particles is performed in a solution in which the nucleating agent or its raw material is dissolved, or a gas or vapor composed of the nucleating agent or its raw material can be used to perform crystallization or synthesis of nano-sized particles.

[0049] The solid-phase method is, for example, a method using a ball mill, bead mill, rod mill, colloid mill, conical mill, disk mill, hammer mill, or jet mill. The liquid-phase method is, for example, a crystallization method, coprecipitation method, sol-gel method, liquid-phase reduction method, or hydrothermal synthesis method. The gas-phase method is, for example, an electric furnace method, chemical flame method, laser method, or thermal plasma method.

[0050] According to the solid-phase method, for example, nucleating agent particles with an average particle diameter in the range of 100 to 150 nm can be obtained. Also, according to the crystallization method, nucleating agent particles with an average particle diameter in the range of 1 to 150 nm can be obtained.

[0051] This masterbatch can further contain additives in addition to the above resin and nucleating agent. The additives are, for example, a heat stabilizer, light stabilizer, anti-blocking agent, catalyst scavenger, gloss modifier, or two or more of them. As the heat stabilizer, phenolic, sulfur-based, phosphorus-based, hydrazine-based, etc., and as the light stabilizer, hindered amine-based, etc., are generally added in any combination.

[0052] The total proportion of the resin and the nucleating agent in the masterbatch is preferably in the range of 90 to 100% by mass, and more preferably in the range of 95 to 100% by mass.

[0053] For this masterbatch, the color coordinates L, a, and b in the Hunter 1948 Lab color space are within the ranges represented by 40 ≦ L ≦ 60, -2 ≦ a ≦ +2, and -3 ≦ b ≦ +3, respectively. For example, the color coordinates L, a, and b are within the ranges represented by 50 ≦ L ≦ 59, -1 ≦ a ≦ +1, and -2 ≦ b ≦ +2, respectively.

[0054] Alternatively, when this masterbatch causes crystallization with a cooling rate of -10 °C / min in differential scanning calorimetry (DSC), it exhibits a crystallization temperature within the range of 130 to 140 °C, a half-width of crystallization energy within the range of 1.0 to 5.5 °C, and a crystallization enthalpy within the range of 115 to 130 mJ / mg. For example, this masterbatch exhibits a crystallization temperature within the range of 132 to 135 °C, a half-width of crystallization energy within the range of 3.5 to 5.0 °C, and a crystallization enthalpy within the range of 120 to 128 mJ / mg. Here, the half-width of the crystallization energy is the full width at half maximum (FWHM) of the valley portion including the peak corresponding to the crystallization energy in the DSC chart obtained by the above measurement.

[0055] Alternatively, this masterbatch has both of the characteristics described above regarding color and crystallization.

[0056] This masterbatch is manufactured by the method described below. According to this method, discoloration of the resin caused by being exposed to an excessively high temperature can be prevented, and the nucleating agent can be distributed in the resin with a high degree of dispersion. Therefore, a masterbatch having the above characteristics can be obtained.

[0057] In the production of the above masterbatch, the raw materials containing the resin and the nucleating agent described above are kneaded in the presence of a supercritical fluid. Here, the amount of the supercritical fluid with respect to 100 parts by mass of the raw materials is within the range of 5 to 20 parts by mass.

[0058] For supercritical fluids, for example, carbon dioxide or nitrogen can be used. The supercritical fluid preferably consists of carbon dioxide. Carbon dioxide becomes a supercritical fluid under conditions of 31°C or higher and 7.4 MPa or higher.

[0059] The supercritical fluid has a density close to that of a liquid and a diffusion coefficient close to that of a gas. And the supercritical fluid easily impregnates into the molten resin. Therefore, the supercritical fluid enhances the fluidity of the above raw material in which the resin is in a molten state.

[0060] When the fluidity of the raw material is low, if an attempt is made to sufficiently heat the raw material in a region away from the heater, the raw material in the region near the heater can be heated to an excessively high temperature. Also, when the fluidity of the raw material is low, a large amount of frictional heat can be generated during kneading. As a result, discoloration of the resin, for example, yellowing, may occur.

[0061] As described above, when kneading is performed in the presence of a supercritical fluid, the fluidity of the raw material can be enhanced. Therefore, the raw material can be heated uniformly, and the frictional heat generated during kneading can be reduced. Accordingly, discoloration of the resin caused by being exposed to an excessively high temperature can be prevented.

[0062] Also, since the supercritical fluid enhances the fluidity of the above raw material in which the resin is in a molten state, a nucleating agent can be distributed in the resin with a high degree of dispersion. Therefore, according to this method, a masterbatch having the above characteristics can be obtained.

[0063] This kneading may be performed batchwise or continuously. For continuous kneading, for example, a kneading extruder can be used.

[0064] When using a kneading extruder, for example, the above raw materials are put into the kneading extruder, and a supercritical fluid is supplied to the kneading extruder into which the raw materials are put. Alternatively, the above raw materials are put into the kneading extruder, and a fluid is supplied to the kneading extruder into which the raw materials are put to generate a supercritical fluid from the fluid in the kneading extruder. The pressure inside the kneading extruder is higher on the downstream side compared to the upstream side. Therefore, a fluid such as a gas can be supplied to the kneading extruder, and the fluid can be changed into a supercritical fluid in the kneading extruder.

[0065] As the kneading extruder, for example, one having an inlet for charging the above raw materials, an outlet for discharging the kneaded product obtained by kneading the raw materials, and a supply port provided between the inlet and the outlet is used. And the above supercritical fluid or gas is supplied to the kneading extruder from the supply port. As described above, the pressure inside the kneading extruder is higher on the downstream side compared to the upstream side. When a supercritical fluid or gas is supplied to the kneading extruder from the supply port provided between the inlet and the outlet, a sufficient amount of supercritical fluid or gas can be supplied to the kneading extruder without disturbing the charging of the raw materials into the kneading extruder.

[0066] The above kneading is preferably carried out by setting the temperature of the heater within the range of 180 to 240 °C, more preferably within the range of 190 to 230 °C. If the set temperature of the heater is low, an extremely high pressure may be required to generate or maintain a supercritical state in the apparatus, or the fluidity of the raw materials on the upstream side may become insufficient when kneading is carried out continuously. If the temperature of the heater is increased, there is a possibility of resin discoloration.

[0067] <2> Transparent Resin and Transparent Resin Molded Product The transparent resin according to an embodiment of the present invention contains the above masterbatch and a raw material resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass. Preferably, the transparent resin consists of the above masterbatch and the above raw material resin. The transparent resin can be obtained by melt-kneading the masterbatch and the raw material resin.

[0068] As the raw material resin, those described for the resin of the masterbatch can be used. The raw material resin preferably has the same composition as the resin of the masterbatch.

[0069] The proportion of the masterbatch in the transparent resin is preferably in the range of 1 to 100% by mass, and more preferably in the range of 5 to 50% by mass.

[0070] The above-mentioned transparent resin can be used for the production of transparent resin molded articles. The transparent resin molded article may have any shape. According to one example, the transparent resin molded article is a transparent resin layer.

[0071] According to one example, the above-mentioned transparent resin and transparent resin molded article have a haze value of 15% or less, and the color coordinates L, a, and b in the Hunter 1948 Lab color space are within the ranges represented by 40 ≦ L ≦ 50, -1 ≦ a ≦ +1, and -2 ≦ b ≦ +2, respectively. The haze value is, for example, in the range of 6 to 8.5%. Also, the color coordinates L, a, and b are, for example, within the ranges represented by 42 ≦ L ≦ 46, -0.8 ≦ a ≦ +0.5, and -1.0 ≦ b ≦ +1.5, respectively.

[0072] According to another example, when crystallization is caused with a temperature decrease rate of -10 °C / min in differential scanning calorimetry (DSC), the above-mentioned transparent resin and transparent resin molded article exhibit a crystallization temperature in the range of 130 to 140 °C, a half-width of the crystallization energy in the range of 1.0 to 5.5 °C, and a crystallization enthalpy in the range of 115 to 130 mJ / mg. These transparent resin and transparent resin molded article exhibit, for example, a crystallization temperature in the range of 132 to 134 °C, a half-width of the crystallization energy in the range of 3.5 to 4.5 °C, and a crystallization enthalpy in the range of 115 to 125 mJ / mg. The half-width of the crystallization energy is the full width at half maximum (FWHM) of the valley portion including the peak corresponding to the crystallization energy in the DSC chart obtained by the above measurement.

[0073] According to another example, the above-mentioned transparent resin and the transparent resin molded article have both of the characteristics described above with respect to color and crystallization.

[0074] The transparent resin layer preferably has a tensile elastic modulus in the range of 800 to 2000 MPa and an elongation at break of 200% or more. In addition, the elongation at break is, for example, 320% or less.

[0075] Here, the elongation at break is a value representing the elongation when a sample is pulled at a predetermined speed and broken, and is a value obtained by dividing the value obtained by subtracting the length (L0) of the sample before the test from the length (L) of the sample at the time of break by the length (L0) of the sample before the test and expressing it as a percentage. A sheet or film with an excessively small value is difficult to stretch, and therefore is likely to cause cracks and whitening during post-processing such as V-groove bending.

[0076] The tensile elastic modulus is a value calculated from the slope of the elastic region where stress and strain are in a proportional relationship in the stress-strain curve obtained by the above test of the elongation at break. A sheet or film with an excessively small value is too soft, and therefore is likely to cause appearance defects due to wrinkles, etc. when, for example, attaching to a support. Also, a sheet or film with an excessively large value has insufficient flexibility, and is likely to cause appearance defects such as wrinkles due to a decrease in adhesion to a support, for example.

[0077] According to one example, the transparent resin layer has a thickness in the range of 20 to 250 μm. According to another example, the thickness of the transparent resin layer is in the range of 30 to 150 μm.

[0078] The transparent resin layer may be capable of being handled alone by itself, or may be one of the layers included in the laminate described later. The transparent resin layer or the laminate can be used as various articles such as packaging materials, electronic components, and cosmetic sheets.

[0079] <3>Laminate The laminate includes the above-mentioned transparent resin layer and one or more other layers. The laminate may contain the above-mentioned transparent resin layer at any position. For example, a laminate containing three or more layers may contain the above-mentioned transparent resin layer as one of the outermost layers or as an intermediate layer. Also, the laminate may contain only one of the above-mentioned transparent resin layers or may contain a plurality of them. Hereinafter, as an example of the laminate, a cosmetic sheet will be described.

[0080] Figure 1 is a cross-sectional view of a cosmetic material including a cosmetic sheet according to an embodiment of the present invention.

[0081] The cosmetic material 11 shown in Figure 1 includes a base material B and a cosmetic sheet 1 attached thereto. Here, the cosmetic material 11 is a decorative board. The decorative board may be a flat plate, or may be bent or folded. The cosmetic material 11 may have a shape other than a plate.

[0082] The base material B is a plate material here. The plate material is, for example, a wooden board, an inorganic board, a metal plate, or a composite board made of a plurality of materials. The base material B may have a shape other than a plate.

[0083] The cosmetic sheet 1 is an example of a laminate including the above-mentioned transparent resin layer. The cosmetic sheet 1 includes a base fabric layer 2, a pattern layer 3, a transparent resin layer 4, a surface protection layer 5, an adhesive layer 7, a primer layer 6, and a concealing layer 8. The pattern layer 3, the adhesive layer 7, the transparent resin layer 4, and the surface protection layer 5 are provided in this order from the side of the base fabric layer 2 on the side opposite to the surface facing the base material B of the base fabric layer 2. The concealing layer 8 and the primer layer 6 are provided in this order from the side of the base fabric layer 2 on the surface facing the base material B of the base fabric layer 2. One or more of the pattern layer 3, the surface protection layer 5, the primer layer 6, the adhesive layer 7, and the concealing layer 8 may be omitted. Hereinafter, the elements included in the cosmetic sheet 1 will be sequentially described.

[0084] <3.1>Base fabric layer As the base fabric layer 2 or its material, for example, those arbitrarily selected from paper, synthetic resin, synthetic resin foam, rubber, non-woven fabric, synthetic paper, metal foil, etc. can be used.

[0085] Examples of the paper include tissue paper, titanium paper, resin-impregnated paper, etc. Examples of the synthetic resin include polyethylene, polypropylene, polybutylene, polystyrene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, acrylic, etc. Examples of the rubber include ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene block copolymer rubber, styrene-butadiene-styrene block copolymer rubber, polyurethane, etc. As the non-woven fabric, organic or inorganic non-woven fabrics can be used. Examples of the metal of the metal foil include aluminum, iron, gold, silver, etc.

[0086] When the base web layer 2 contains a synthetic resin, it may further contain inorganic particles. Examples of the inorganic particles include particles made of calcium carbonate, talc, or titanium oxide. Incorporating inorganic particles into the base web layer 2 improves the non-combustibility or flame retardancy of the decorative sheet 1.

[0087] <3.2> Primer layer When an olefin-based resin is used as the material of the base web layer 2, the surface of the base web layer 2 is often in an inactive state. Therefore, in this case, it is preferable to provide a primer layer 6 between the base web layer 2 and the base material B. When the base web layer 2 is made of an olefin-based material, the primer layer 6 can be omitted, and in order to improve the adhesiveness between the base web layer 2 and the base material B, surface modification treatments such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, dichromic acid treatment, etc. may be performed on the base web layer 2.

[0088] As the material of the primer layer 6, for example, the materials described later for the pattern layer 3 can be used. Since the primer layer 6 is applied to the back surface of the decorative sheet 1, considering that the decorative sheet 1 is wound in a web shape, an inorganic filler may be added to the primer layer 6 in order to avoid blocking and enhance the adhesion to the adhesive. Examples of the inorganic filler include silica, alumina, magnesia, titanium oxide, barium sulfate, and the like.

[0089] <3.3> Concealing layer In order to impart concealment to the substrate B to the decorative sheet 1, for example, a colored sheet is used as the base web layer 2, or an opaque concealing layer 8 is provided. The concealing layer 8 can be composed of, for example, the same materials as those described later for the pattern layer 3. However, since the concealing layer 8 is for the purpose of concealment, as the pigment, for example, an opaque pigment, titanium oxide, iron oxide, etc. are preferably used. Also, in order to enhance the concealment, it is also possible to add a metal such as gold, silver, copper, aluminum, etc. to the material of the concealing layer 8. Generally, flaky aluminum pieces are often added.

[0090] <3.4> Pattern layer The pattern layer 3 is a layer formed by printing a pattern on the base fabric layer 2 using ink. As the binder of the ink, for example, nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyesters, or modified products thereof can be used alone or in combination. The binder can be any of aqueous, solvent-based, and emulsion types, and can be either a one-component type or a two-component type using a curing agent. The pattern layer 3 may be formed by a method of curing a layer formed of curable ink by irradiation with ultraviolet rays, electron beams, or the like. The most common method is a method using urethane-based ink, which is cured by isocyanate. The ink used to form the pattern layer 3 can further contain, in addition to the binder, for example, colorants such as pigments and dyes contained in ordinary ink, extender pigments, solvents, various additives, and the like. Examples of highly versatile pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and pearl pigments such as mica.

[0091] Also, separately from the application of the ink, it is also possible to apply a design to the pattern layer 3 by vapor deposition or sputtering of various metals. In particular, it is preferable that a light stabilizer is added to the above ink. Thereby, deterioration of the decorative sheet 1 itself caused by photo-degradation of the ink can be suppressed, and the life of the decorative sheet 1 can be extended.

[0092] <3.5>Adhesive layer The adhesive layer 7 is a layer also called a heat-sensitive adhesive layer, an anchor coat layer, or a dry lamination adhesive layer.

[0093] The resin material of the adhesive layer 7 is not particularly limited. For example, it can be appropriately selected and used from resin materials such as acrylic, polyester, polyurethane, and epoxy. Also, as the resin material of the adhesive layer 7, for example, an ethylene-vinyl acetate copolymer resin-based adhesive can also be used. The coating method can be appropriately selected according to the viscosity of the adhesive, etc. Generally, gravure coating is used. After forming the adhesive layer 7 by gravure coating on the upper surface of the pattern layer 3, the transparent resin layer 4 is laminated. Note that the adhesive layer 7 can be omitted when sufficient adhesive strength can be obtained between the transparent resin layer 4 and the pattern layer 3.

[0094] <3.6>Transparent resin layer The transparent resin layer 4 is the transparent resin layer described in detail above. Here, the transparent resin layer 4 has a flat upper surface. An uneven structure may be provided on the upper surface of the transparent resin layer 4. As a method of providing an uneven structure on the upper surface of the transparent resin layer 4, for example, a method of applying heat and pressure with an embossing plate pressed against the upper surface of the transparent resin layer 4 laminated to another layer by various methods, and a method of using a cooling roll having an uneven structure on the surface when forming the transparent resin layer 4 using an extruder. When an uneven structure is provided on the upper surface of the transparent resin layer 4, it is also possible to embed ink in the concave portions to further improve the design property.

[0095] <3.7>Surface protection layer The surface protection layer 5 is a colorless and transparent resin layer. Here, an uneven structure is provided on the upper surface of the surface protection layer 5. The upper surface of the surface protection layer 5 may be flat.

[0096] The surface protection layer 5 contains a cured product of a resin. This resin is, for example, a thermosetting resin, an ionizing radiation curable resin, or a combination thereof. The form of the resin is, for example, aqueous, emulsion, solvent-based, or solventless. Here, "ionizing radiation" is a charged particle beam such as an electron beam. The ionizing radiation curable resin cures by irradiation with ionizing radiation. Also, the ionizing radiation curable resin can also cure by ultraviolet irradiation.

[0097] As the thermosetting resin, it is preferable to use a two-component curable urethane-based thermosetting resin. The urethane-based thermosetting resin is suitable from the viewpoints of workability, price, and cohesive force of the resin itself. As the urethane-based resin, a resin obtained by reacting an acrylic polyol and an isocyanate may be used. The isocyanate can be appropriately selected from, for example, tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), lysine diisocyanate (LDI), isophorone diisocyanate (IPDI), bis(isocyanatomethyl)cyclohexane (HXDI), and trimethylhexamethylene diisocyanate (TMDI); adducts, biuret bodies or isocyanurate bodies which are derivatives thereof; and prepolymers thereof. Considering weather resistance, it is preferable to use those based on hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI) having a linear molecular structure.

[0098] As the radiation-curable resin, known ones such as various monomers and commercially available oligomers can be used. For example, acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, and epoxy resins can be used. The radiation-curable resin may be either an aqueous resin or a non-aqueous (organic solvent-based) resin. The acrylic resin can be appropriately selected from, for example, polyester acrylate-based resins, epoxy acrylate-based resins, urethane acrylate-based resins, and acrylic acrylate-based resins. In particular, it is preferable to use a urethane acrylate-based resin or an acrylic acrylate-based resin having good weather (light) resistance. From the viewpoint of workability, it is preferable to cure the radiation-curable resin with active energy rays such as ultraviolet rays and electron beams.

[0099] As the mixture of the thermosetting resin and the radiation-curable resin, it is preferable to use a mixture of a urethane resin as a thermosetting resin obtained by reacting an acrylic polyol and an isocyanate, and a urethane acrylate resin as a photocurable resin. In this case, it is particularly advantageous in terms of improving surface hardness, suppressing curing shrinkage, and adhesion to inorganic fine particles.

[0100] The surface protection layer 5 can further contain inorganic particles. Examples of the inorganic particles include particles made of alumina, silica, boehmite, iron oxide, magnesium oxide, or diamond. The average particle diameter of the inorganic particles is, according to one example, in the range of 1 to 100 μm, and according to another example, in the range of 1 to 30 μm.

[0101] The inorganic particle content rate of the surface protection layer 5 is, according to one example, in the range of 0.1 to 30 parts by mass, and according to another example, in the range of 1 to 20 parts by mass with respect to 100 parts by mass of the resin component. When the surface protection layer 5 contains inorganic particles, its scratch resistance is improved. However, if the inorganic particle content rate is excessively increased, the transparency may be reduced due to the light scattering effect of the inorganic particles, or the cost may increase.

[0102] The surface protection layer 5 can be formed by a known method. The surface protection layer 5 having an uneven structure on the upper surface is formed by performing, in this order, a first irradiation step of irradiating a coating film made of an ionizing radiation curable resin with light (first radiation) having a wavelength of 200 nm or less, and a second irradiation step of irradiating the coating film with ionizing radiation such as an electron beam or ultraviolet light having a longer wavelength than the first radiation as the second radiation. Alternatively, the surface protection layer 5 having an uneven structure on the upper surface can be formed by forming a coating film made of an ionizing radiation curable resin or a thermosetting resin, pressing a plate against the coating film, curing the coating film in this state, and then removing the plate from the cured film. The leaf surface protection layer having a flat upper surface can be formed by forming a coating film made of an ionizing radiation curable resin or a thermosetting resin and curing the coating film. For forming the coating film, various printing methods such as a gravure printing method, an offset printing method, a screen printing method, a flexographic printing method, an electrostatic printing method, and an inkjet printing method, and various coating methods such as a roll coating method, a knife coating method, a microgravure coating method, and a die coating method can be used.

Example

[0103] Examples of the present invention are described below. <Example 1> (Manufacture of masterbatch) First, a masterbatch composed of a polyolefin resin and an additive was manufactured by the following method.

[0104] As the polyolefin resin, a highly crystalline homopolypropylene resin with an isotactic pentad fraction of 97.8%, a melt flow rate (MFR) of 15 g / 10 min (230 °C), and a molecular weight distribution (MWD; Mw / Mn) of 2.3 was used. To this polyolefin resin, as additives, 500 ppm of a hindered phenolic antioxidant (Irganox (registered trademark) 1010; manufactured by BASF), 20,000 ppm of a benzotriazole-based ultraviolet absorber (Tinuvin (registered trademark) 328; manufactured by BASF), 20,000 ppm of a hindered amine-based light stabilizer (Chimasorb (registered trademark) 944; manufactured by BASF), and 10,000 ppm of a nucleating agent (Adekastab (registered trademark) NA-21; manufactured by Adeka) were added. Here, the amounts expressed in ppm are the mass ratios of the respective additives based on the total amount of the polyolefin resin and all the additives.

[0105] The raw material obtained by adding the above additives to the polyolefin resin was kneaded using a kneading extruder equipped with a strand die at the discharge port and a fluid supply device installed at an intermediate position in the kneading section, while supplying carbon dioxide from the fluid supply device into the kneading extruder. Here, the temperature of the heater was set to 230 °C, the pressure at the intermediate position of the kneading section was set to 8 MPa, and the amount of carbon dioxide with respect to 100 parts by mass of the raw material was set to 6 parts by mass.

[0106] The strands discharged through the strand die were cooled and then cut to obtain a masterbatch.

[0107] (Manufacture of Transparent Resin Sheet) A transparent resin sheet was produced using the above masterbatch. Specifically, 10 parts by mass of the above masterbatch was added to 100 parts by mass of the same polyolefin resin used in the production of the above masterbatch, and 500 ppm of a hindered phenol antioxidant (Irganox (registered trademark) 1010: manufactured by BASF) was further added. Then, these mixtures were extruded using a melt extruder to form a transparent resin sheet with a thickness of 80 μm as a transparent resin layer. Next, corona treatment was performed on both sides of this transparent resin sheet to make the surface wetting tension 40 dyn / cm or more.

[0108] (Manufacture of decorative sheet) A decorative sheet was produced using the above transparent resin sheet. Specifically, first, a base fabric layer with a thickness of 70 μm having concealability was prepared. Next, pattern printing using a two-component curable urethane ink (V180: manufactured by Toyo Ink Co., Ltd.) was performed on one surface of the base fabric layer to form a pattern layer. Also, a primer coat was applied to the other surface of the base fabric layer to form a primer layer. Then, the base fabric layer and the above transparent resin sheet were laminated by the dry lamination method so that the pattern layer faced the transparent resin layer. In this dry lamination, a dry lamination adhesive (Takelac (registered trademark) A540: manufactured by Mitsui Chemicals, Inc.) was applied at a coating amount of 2 g / m 2 . Next, pressing was performed on the upper surface of the transparent resin sheet using an embossing mold roll to provide an uneven structure. Then, a two-component curable urethane top coat (W184: manufactured by DIC Graphics Co., Ltd.) was applied on the transparent resin sheet at a coating amount of 3 g / m 2 , and this coating film was cured to form a surface protective layer. In the above manner, a decorative sheet with a thickness of 154 μm was obtained.

[0109] <Example 2> In this example, in the production of the masterbatch, instead of using AdekaStab (registered trademark) NA-21 manufactured by Adeka Corporation as a nucleating agent, AdekaStab (registered trademark) NA-11 manufactured by Adeka Corporation was used, and the masterbatch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 1.

[0110] <Example 3> In this example, in the production of the masterbatch, instead of setting the amount of carbon dioxide supplied into the kneading extruder to 6 parts by mass with respect to 100 parts by mass of the raw material, it was set to 20 parts by mass with respect to 100 parts by mass of the raw material. Otherwise, in the same manner as in Example 1, a masterbatch, a transparent resin sheet, and a decorative sheet were produced.

[0111] <Comparative Example 1> In this example, in the production of the masterbatch, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that the supply of carbon dioxide into the kneading extruder was omitted.

[0112] <Comparative Example 2> In this example, in the production of the masterbatch, instead of using AdekaStab (registered trademark) NA-21 manufactured by Adeka Corporation as a nucleating agent, AdekaStab (registered trademark) NA-11 manufactured by Adeka Corporation was used, and a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that the supply of carbon dioxide into the kneading extruder was omitted.

[0113] <Comparative Example 3> In this example, in the production of the masterbatch, instead of setting the amount of carbon dioxide supplied into the kneading extruder to 6 parts by mass with respect to 100 parts by mass of the raw material, it was set to 2 parts by mass with respect to 100 parts by mass of the raw material. Otherwise, in the same manner as in Example 1, a masterbatch, a transparent resin sheet, and a decorative sheet were produced.

[0114] <Comparative Example 4> In this example, first, the nucleating agent was nano-sized by the supercritical reverse phase evaporation method. Specifically, 100 parts by mass of methanol, 82 parts by mass of the nucleating agent (Adekastab (registered trademark) NA-11: manufactured by ADEKA Corporation), and 5 parts by mass of phosphatidylcholine were placed in a high-pressure stainless steel container maintained at 60°C, and the container was sealed. Next, carbon dioxide was injected into the container so that the pressure became 20 MPa to bring the carbon dioxide into a supercritical state. Then, while vigorously stirring the contents of the container, 100 parts by mass of ion-exchanged water was injected into the container. The contents of the container were stirred for 15 minutes while maintaining the temperature and pressure inside the container, and then the carbon dioxide was discharged from the container to return the pressure inside the container to atmospheric pressure, thereby obtaining a nucleating agent-encapsulated vesicle in which the nucleating agent was encapsulated in an outer membrane composed of phospholipid.

[0115] Next, a masterbatch composed of a polyolefin resin and an additive was produced by the following method.

[0116] As the polyolefin resin, the same polyolefin resin as that used in Example 1 was used. To this polyolefin resin, as additives, 500 ppm of a hindered phenol-based antioxidant (Irganox (registered trademark) 1010: manufactured by BASF), 20000 ppm of a benzotriazole-based ultraviolet absorber (Tinuvin (registered trademark) 328: manufactured by BASF), 20000 ppm of a hindered amine-based light stabilizer (Chimasorb (registered trademark) 944: manufactured by BASF), and 10000 ppm of the above nucleating agent-encapsulated vesicle were added. Here, the amount expressed in ppm is the mass ratio of each additive based on the total amount of the polyolefin resin and all the additives.

[0117] Thereafter, the above raw material obtained by adding the above additives to the polyolefin resin was used in place of the raw material used in Example 1, and a masterbatch was produced by the same method as in Example 1 except that the supply of carbon dioxide into the kneading extruder was omitted.

[0118] Also, a transparent resin sheet and a decorative sheet were produced by the same method as in Example 1 except that this masterbatch was used in place of the raw material used in Example 1.

[0119] <Evaluation of Masterbatch and Transparent Resin Sheet> The following evaluations were performed on the masterbatches and transparent resin sheets produced in Examples 1 to 3 and Comparative Examples 1 to 4.

[0120] (Color Evaluation) Using a color chroma meter (CR-241: manufactured by Konica Minolta), the color coordinates L, a, and b of the masterbatch and the transparent resin sheet were measured by focusing on their surfaces.

[0121] (Crystallinity Evaluation) The masterbatch was cut into small pieces, 5 mg was weighed out onto an aluminum pan, and measurements were taken using a differential scanning calorimeter. This measurement was carried out according to a program in which the following first to fifth steps were sequentially performed. The first step is a step of heating the sample from 30°C to 200°C at a rate of 10°C per minute and holding for 1 minute. The second step is a step of performing a quench cool in which the sample is taken out of the sample chamber into the atmosphere and rapidly cooled. The third step is a step of returning the sample to the sample chamber and heating it again from 30°C to 200°C at a rate of 10°C per minute and holding for 1 minute. The fourth step is a step of cooling the sample from 200°C to 30°C at a rate of 10°C per minute, holding for 5 minutes, and measuring the crystallization temperature during cooling. The fifth step is a step of heating the sample again from 30°C to 200°C and measuring the melting peak temperature.

[0122] (Tensile Test) Using a super dumbbell cutter (manufactured by Dumbbell Co., Ltd.) conforming to JIS K-7127-4, a test piece for the tensile test was cut out from the transparent resin sheet. The obtained test piece was set in a tensile tester (manufactured by Tensilon), pulled at a tensile rate of 50 mm / min, and the ratio of the length immediately before the test piece broke to the length before the test was calculated as the tensile fracture elongation. Furthermore, the tensile elastic modulus was calculated from the slope in the elastic region where the stress and strain of the stress-strain curve obtained in the test were in a proportional relationship.

[0123] (Haze Value Measurement Test) The haze value mentioned here is the value obtained by dividing, in percentage, the value obtained by subtracting the parallel light transmittance (the ratio of the total amount of parallel light components among the light rays emitted from the other side, which is the sum of only the amounts of the linear components of the light rays emitted from the other side to the total incident light amount) from the total light transmittance (the ratio of the total transmitted light amount, which is the sum of the amounts of all light rays emitted from the other side when light emitted from an incandescent light source is incident on an object from one side, to the total incident light amount), by the total light transmittance. The smaller the haze value of an object, the higher its transparency.

[0124] The haze value of an object made of a transparent resin is determined by the internal haze that depends on the internal state of the object such as the degree of crystallinity and spherulite size in the crystalline part, and the external haze that depends on the surface state of the object such as the presence or absence of irregularities on the incident and exit surfaces. In this specification, etc., when simply referred to as the haze value, it means the value determined by the internal haze and the external haze.

[0125] Here, the haze value measurement test was performed for each transparent resin sheet using a haze value measuring instrument (NDH2000: manufactured by Nippon Denshoku Co., Ltd.). Specifically, first, a blank measurement was performed with nothing attached to the sample holder. Next, a sample transmittance measurement was performed with a transparent resin sheet attached as a sample to the sample holder. Then, the ratio of the value obtained by the sample transmittance measurement to the value obtained by the blank measurement, expressed as a percentage, was calculated as each transmittance, and the haze value was calculated from these transmittances.

[0126] <Evaluation of Cosmetic Sheet> (Pencil Hardness Test) Pencils with lead hardnesses of 2B, B, HB, F, H, 2H, and 3H were prepared. While making the tip of the lead of the pencil contact the upper surface of the surface protective layer of the cosmetic sheet, fixing the angle formed by the length direction of the pencil at 45 ± 1°, and sliding it with a load of 1 kg applied to the pencil, it was determined whether scratches were formed on the cosmetic sheet (in accordance with the old JIS standard JISK5400). The tests were performed in order from the pencil with the lowest hardness, and the hardness at which scratching marks were first formed was taken as the surface hardness of the cosmetic sheet.

[0127] (V-groove Bending Process Suitability Test) As the base material, medium density fiberboard (MDF) was prepared. Next, a decorative sheet was attached to one side of the base material using a urethane-based adhesive to produce a decorative material. Subsequently, a groove (V-groove) having a V-shaped cross-sectional shape was formed on the other side of the base material to which the decorative sheet was attached. This V-groove was formed such that its bottom reached the boundary between the base material and the decorative sheet and did not damage the decorative sheet. Next, the decorative material was bent at an angle of 90° along the V-groove so that the decorative sheet side became a mountain fold. Then, the mountain fold portion of the decorative sheet was observed with an optical microscope to confirm whether there were any defects such as whitening or cracking at this mountain fold portion, and the post-processability was evaluated according to the following criteria. A: No defects such as whitening and cracking were observed.

[0128] B: Defects such as whitening and cracking were observed.

[0129] <Evaluation Results> The results of the above evaluations are summarized in Tables 1 to 3.

[0130]

Table 1

[0131]

Table 2

[0132]

Table 3

[0133] As shown in Tables 1 to 3, in Comparative Examples 1 and 2 where the masterbatch was produced without a supercritical fluid, and in Comparative Example 3 where a small amount of supercritical fluid was used to produce the masterbatch, the masterbatch and the transparent resin sheet had a large degree of coloring, a small crystallization enthalpy, and a large half-width of the crystallization energy. Also, in Comparative Examples 1 to 3, the elongation at break of the transparent resin sheet was small and the haze was large. And in Comparative Examples 1 to 3, although the pencil hardness of the transparent resin sheet was sufficient, in Comparative Examples 1 and 2, the post-processing property of the decorative sheet was insufficient.

[0134] In Comparative Example 4 where the nucleating agent was nano-sized by the supercritical inverse phase evaporation method, the masterbatch and the transparent resin sheet had a large degree of coloring and a small crystallization enthalpy. In Comparative Example 4, the pencil hardness and post-processing property of the decorative sheet were sufficient.

[0135] On the other hand, in Examples 1 to 3, the masterbatch and the transparent resin sheet had a small degree of coloring, a large crystallization enthalpy, and a small half-width of the crystallization energy. Also, in Examples 1 to 3, the elongation at break of the transparent resin sheet was large and the haze was small. And in Examples 1 to 3, the pencil hardness and post-processing property of the decorative sheet were sufficient.

Explanation of Reference Signs

[0136] 1... Decorative sheet, 2... Base film layer, 3... Pattern layer, 4... Transparent resin layer, 5... Surface protection layer, 6... Primer layer, 7... Adhesive layer, 8... Concealing layer, 11... Decorative material, B... Substrate.

Claims

1. A masterbatch for manufacturing a transparent resin molded article, comprising a resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass and a nucleating agent, and the color coordinates L, a, and b in the Hunter 1948 Lab color space are respectively within the ranges represented by 40 ≦ L ≦ 60, -2 ≦ a ≦ +2, and -3 ≦ b ≦ +3.

2. A masterbatch for manufacturing a transparent resin molded article, comprising a resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass and a nucleating agent, and when crystallization is caused with a temperature decrease rate of -10°C / min in differential scanning calorimetry, it shows a crystallization temperature in the range of 130 to 140°C, a half-width of the crystallization energy in the range of 1.0 to 5.5°C, and a crystallization enthalpy in the range of 115 to 130 mJ / mg.

3. The masterbatch according to claim 1 or 2, and a raw material resin in which the proportion of the polyolefin resin is in the range of 90 to 100% by mass to form a transparent resin.

4. The transparent resin according to claim 3, wherein the polyolefin resin contained in the masterbatch and the raw material resin is a highly crystalline polypropylene resin having an isotactic pentad fraction (mmmm fraction) of 95% or more.

5. A transparent resin molded article made of the transparent resin according to claim 3.

6. A transparent resin layer made of the transparent resin according to claim 3.

7. The transparent resin layer according to claim 6, having a haze value of 15% or less, and the color coordinates L, a, and b in the Hunter 1948 Lab color space are respectively within the ranges represented by 40 ≦ L ≦ 50, -1 ≦ a ≦ +1, and -2 ≦ b ≦ +2.

8. The transparent resin layer according to claim 6, which shows a crystallization temperature in the range of 130 to 140°C, a half-width of the crystallization energy in the range of 1.0 to 5.5°C, and a crystallization enthalpy in the range of 115 to 130 mJ / mg when crystallization is caused with a temperature decrease rate of -10°C / min in differential scanning calorimetry.

9. The transparent resin layer according to claim 6, having a tensile modulus in the range of 800 to 2000 MPa and a tensile elongation at break of 200% or more.

10. The transparent resin layer according to claim 6, having a thickness in the range of 20 to 250 μm.

11. A laminate comprising the transparent resin layer according to claim 6 and one or more other layers.

12. The laminate according to claim 11, which is a decorative sheet.

13. A method for producing a masterbatch, which includes kneading a raw material containing a resin with a proportion of polyolefin resin within the range of 90 to 100% by mass and a nucleating agent in the presence of a supercritical fluid, and setting the amount of the supercritical fluid to be within the range of 5 to 20 parts by mass with respect to 100 parts by mass of the raw material.

14. The method for producing a masterbatch according to claim 13, wherein the raw material is charged into a kneading extruder, and the supercritical fluid is supplied to the kneading extruder into which the raw material has been charged, or a fluid is supplied to the kneading extruder into which the raw material has been charged to generate the supercritical fluid from the fluid in the kneading extruder.

15. The kneading extruder has a charging port for charging the raw material, a discharge port for discharging a kneaded product obtained by kneading the raw material, and a supply port provided between the charging port and the discharge port, and the supercritical fluid or the fluid is supplied to the kneading extruder from the supply port. The method for producing a masterbatch according to claim 14.

16. The method for producing a masterbatch according to claim 13, wherein the supercritical fluid consists of carbon dioxide.

17. A method for producing a transparent resin, which includes kneading a masterbatch produced by the production method according to claim 16 and a raw material resin with a proportion of polyolefin resin within the range of 90 to 100% by mass.

18. A method for producing a transparent resin molded article, which includes producing a transparent resin by the production method according to claim 17 and molding the transparent resin to obtain a molded article.

19. A method for producing a transparent resin layer, which includes producing a transparent resin by the production method according to claim 17 and molding the transparent resin to obtain a resin layer.

20. A method for producing a laminate, which includes producing a transparent resin by the production method according to claim 17 and molding the transparent resin to obtain a transparent resin layer.

Images