Additive for resin molding and method for producing the same

Abstract

To provide a technology related to improvement of functionality of a resin molding.SOLUTION: A method for producing an additive for a resin molding includes decompressing a fluid containing a supercritical fluid, and a third raw material additive containing a first raw material additive soluble in the supercritical fluid and a second raw material additive insoluble in the supercritical fluid, and obtaining an additive having a smaller average particle diameter compared to the third raw material additive.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing an additive for a resin molded product. [Background technology]

[0002] Molded articles made of resin are used in a variety of fields. For example, laminated films made of multiple resin layers can exhibit performance and functions that cannot be achieved by single-layer films, and are therefore used in a wide range of fields, including decorative sheets, packaging materials, and electronic components.

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

[0004] Decorative sheets generally use polyvinyl chloride, as described in Patent Document 1. However, such decorative sheets generate toxic gases when burned. For this reason, many decorative sheets have been proposed that use polyolefin resins instead of polyvinyl chloride, as described in Patent Documents 2 to 4.

[0005] Decorative sheets that use polyolefin resins instead of polyvinyl chloride do not emit chlorine-derived toxic gases when burned. However, because these decorative sheets use general polypropylene sheets or soft polypropylene sheets, they have far inferior scratch resistance compared to decorative sheets that use polyvinyl chloride.

[0006] The use of highly crystalline polypropylene, which has a high initial bending modulus, as the polyolefin resin can achieve excellent abrasion resistance. However, decorative sheets using such highly crystalline polypropylene can sometimes break or crack around the periphery when subjected to bending processes such as V-groove bending.

[0007] Furthermore, polypropylene resins are usually milky white because their spherulite size is larger than the wavelength of visible light (400 to 750 nm). In decorative sheets, the transparent resin layer is required to protect the underlying pattern layer and base sheet, while not interfering with the visibility of the patterns and designs printed thereon from the outermost surface of the decorative sheet.

[0008] To address these issues, Patent Document 5 describes the encapsulation of a nucleating agent in an outer membrane made of phospholipids by supercritical reverse-phase evaporation, and the addition of the resulting vesicles to a crystalline polypropylene resin. The vesicles obtained by supercritical reverse-phase evaporation are extremely small in size. Therefore, adding these vesicles to a crystalline polypropylene resin can significantly reduce the size of the spherulites and dramatically improve the crystallinity of the crystalline portion. As a result, high transparency can be achieved, as well as excellent scratch resistance and post-processing resistance.

[0009] The nano-processing of nucleating agents using the supercritical reverse-phase evaporation method described above involves injecting an aqueous phase into a mixture of supercritical carbon dioxide, an organic solvent, a phospholipid, and a nucleating agent, followed by vigorous stirring to generate an emulsion of supercritical carbon dioxide and an aqueous phase. The carbon dioxide then expands and evaporates under reduced pressure, resulting in phase inversion, producing vesicles consisting of nanocapsules in which the phospholipid covers the surface of the nucleating agent with a monolayer membrane. In this nano-processing, there is concern about vesicle size variation depending on the degree of stirring and mixing. Furthermore, from the perspective of production cost, it is desirable to reduce the number of steps and enable production using a simple manufacturing method. Furthermore, a common problem with resin molded products is the bleed-out phenomenon, in which incorporated additives and residual solvents rise to the surface over time. Therefore, it is preferable to reduce the types and amounts of these additives and organic solvents. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Publication No. 2-128843 [Patent Document 2] Japanese Patent Application Publication No. 5-278137 [Patent Document 3] Japanese Patent Application Publication No. 6-198831 [Patent Document 4] Japanese Patent Application Publication No. 9-328562 [Patent Document 5] Japanese Patent Application Laid-Open No. 2016-168830 Summary of the Invention [Problem to be solved by the invention]

[0011] Various additives are used in various resin molded products, such as stabilizers to prevent deterioration due to heat, light, oxidation, etc. during or after molding processing, modifiers to impart strength, transparency, color tone, etc., and nucleating agents. If the functions of the various additives used in these resin molded products can be maximized, the functionality of the resin molded products can be significantly improved.

[0012] An object of the present invention is to provide a technique for improving the functionality of a resin molded product. [Means for solving the problem]

[0013] According to one aspect of the present invention, there is provided a method for producing an additive for a resin molded product, the method comprising reducing the pressure of a fluid containing a supercritical fluid and a third raw material additive, the third raw material additive including a first raw material additive soluble in the supercritical fluid and a second raw material additive insoluble in the supercritical fluid, to obtain an additive having a smaller average particle size than the first raw material additive.

[0014] According to another aspect of the present invention, there is provided a method for producing an additive for a resin molded product according to the above aspect, which comprises obtaining, as the additive, composite particles containing particles of a second additive derived from the second raw material additive and a first additive derived from the first raw material additive supported on particles of the second additive.

[0015] According to yet another aspect of the present invention, there is provided the method for producing an additive for a resin molded product according to the above aspect, wherein the first additive coats the surfaces of particles of the second additive.

[0016] According to yet another aspect of the present invention, there is provided the method for producing an additive for a resin molded product according to the above aspect, wherein the first raw material additive is a surfactant.

[0017] According to yet another aspect of the present invention, there is provided the method for producing an additive for a resin molded product according to any one of the above aspects, wherein the second raw material additive is a nucleating agent.

[0018] According to yet another aspect of the present invention, there is provided the method for producing an additive for a resin molded product according to any one of the above aspects, wherein the second raw material additive is porous.

[0019] According to yet another aspect of the present invention, there is provided a method for producing an additive for a resin molded product according to the above aspect, which includes obtaining a mixture containing, as the additive, particles of a first additive derived from the first raw material additive and particles of a second additive derived from the second raw material additive.

[0020] According to yet another aspect of the present invention, there is provided a method for producing an additive for a resin molded product according to any of the above aspects, in which the average particle size of the third raw material additive is 2 μm or more, and the additive has an average particle size of 5000 nm or less.

[0021] According to yet another aspect of the present invention, there is provided the method for producing an additive for a resin molded product according to any one of the above aspects, wherein the supercritical fluid comprises carbon dioxide.

[0022] According to yet another aspect of the present invention, there is provided the method for producing an additive for a resin molded product according to any one of the above aspects, wherein the pressure reduction of the fluid is carried out in a pressure-resistant container.

[0023] According to yet another aspect of the present invention, there is provided a method for producing a masterbatch, the method including producing an additive for a resin molded product by the method for producing the additive according to any one of the above aspects, and kneading a raw material containing a first raw material resin and the additive.

[0024] According to yet another aspect of the present invention, there is provided a method for producing a masterbatch according to the above aspect, which comprises kneading the raw materials in the presence of a supercritical fluid.

[0025] According to yet another aspect of the present invention, there is provided a method for producing a masterbatch according to any of the above aspects, wherein the first raw material resin is a resin in which the proportion of polyolefin resin is in the range of 90 to 100 mass %.

[0026] According to yet another aspect of the present invention, there is provided a method for producing a resin, the method including producing a masterbatch by the method for producing a masterbatch according to any of the above aspects, and kneading a raw material including the masterbatch and a second raw material resin.

[0027] According to yet another aspect of the present invention, there is provided a method for producing a resin according to the above aspect, wherein the first raw resin and the second raw resin are each independently a resin having a polyolefin resin content in the range of 90 to 100 mass %.

[0028] According to yet another aspect of the present invention, there is provided a method for manufacturing a resin molded product, the method including manufacturing the resin by the resin manufacturing method according to the above aspect, and molding the resin to manufacture a resin molded product.

[0029] According to yet another aspect of the present invention, there is provided the method for producing a resin molded article according to the above aspect, wherein the concentration of the additive in the resin molded article is within a range of 0.005 to 1.0 mass %.

[0030] According to yet another aspect of the present invention, there is provided a method for producing a resin molded article according to any one of the above aspects, wherein the resin molded article is a resin layer.

[0031] According to yet another aspect of the present invention, a resin molded article is manufactured by forming the resin layer by the method for manufacturing a resin molded article according to any one of the above aspects, and laminating one or more other layers on the resin layer. A method for manufacturing a laminate comprising:

[0032] According to yet another aspect of the present invention, there is provided a method for producing a laminate according to the above aspect, wherein the laminate is a decorative sheet.

[0033] According to yet another aspect of the present invention, there is provided an additive for resin molding products, comprising a first additive soluble in a supercritical fluid and a second additive insoluble in the supercritical fluid, The additive for resin molding products has an average particle size of 5000 nm or less.

[0034] According to yet another aspect of the present invention, there is provided an additive for resin molding products according to the above aspect, wherein the additive for resin molding products is a composite particle containing particles of the second additive and the first additive supported on the particles of the second additive.

[0035] According to yet another aspect of the present invention, there is provided the additive for resin molding articles according to the above aspect, wherein the first additive coats the surfaces of particles of the second additive.

[0036] According to yet another aspect of the present invention, there is provided an additive for resin molding products according to the above aspect, wherein the additive for resin molding products is a mixture containing particles of the first additive and particles of the second additive.

[0037] According to yet another aspect of the present invention, there is provided a masterbatch containing the additive for resin molding according to any one of the above aspects and a first raw resin.

[0038] According to yet another aspect of the present invention, there is provided a resin containing the masterbatch according to the above aspect and a second raw resin.

[0039] According to yet another aspect of the present invention, there is provided a resin molded product obtained by molding the resin according to the above aspect.

[0040] According to yet another aspect of the present invention, there is provided a resin layer obtained by molding the resin according to the above aspect.

[0041] According to yet another aspect of the present invention, there is provided a laminate including the resin layer according to the above aspect and one or more other layers provided on the resin layer.

[0042] According to yet another aspect of the present invention, there is provided a decorative sheet including a resin layer according to the above aspect and one or more other layers provided on the resin layer. [Effects of the Invention]

[0043] The present invention provides a technique for improving the functionality of a resin molded product. [Brief explanation of the drawings]

[0044] [Figure 1] FIG. 1 is a cross-sectional view of a decorative material including a decorative sheet according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0045] The following describes embodiments of the present invention. The embodiments described below are more specific embodiments of any of the above aspects. The following items can be incorporated into each of the above aspects, either singly or in combination.

[0046] Furthermore, the embodiments shown below are merely 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 components described below. Various modifications can be made to the technical idea of ​​the present invention within the technical scope defined by the claims.

[0047] It should be noted 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 component and the dimensions of another component, etc. may differ from the actual figures.

[0048] <1> Additives for resin moldings A method for producing an additive for a resin molded product according to one embodiment of the present invention includes reducing the pressure of a fluid containing a supercritical fluid and a third raw material additive, the third raw material additive including a first raw material additive soluble in the supercritical fluid and a second raw material additive insoluble in the supercritical fluid, to obtain an additive having a smaller average particle size than the third raw material additive.

[0049] The above method will be described below. In the following description, the "additive having a smaller average particle size than the third raw material additive" obtained by this method will also be referred to as "additive" or "additive fine particles."

[0050] There are a wide variety of additives used in resin molded products, some of which improve the physical properties of the resin, some of which give the resin properties that it does not originally have, etc. The above method can be applied to the microparticulation treatment of various additives added to resins.

[0051] The supercritical fluid may be, for example, carbon dioxide or nitrogen. Carbon dioxide becomes a supercritical fluid under conditions of 31.1°C or higher and 7.38 MPa or higher. Carbon dioxide is preferably used as the supercritical fluid because of its high safety and low critical temperature of 31.1°C.

[0052] The first raw material additive is soluble in the supercritical fluid, and the second raw material additive is insoluble in the supercritical fluid. Whether a raw material additive is a first raw material additive soluble in the supercritical fluid or a second raw material additive insoluble in the supercritical fluid can be determined as follows. That is, 50 mg of the raw material additive is placed in a 5 mL pressure-resistant container. Supercritical fluid is injected into the container to achieve 40°C and 20 MPa, and the container is maintained under these conditions for 10 minutes. The pressure-resistant container is then opened, and the mass of the remaining raw material additive is measured. If the mass of the remaining raw material additive is 40 mg or less, the raw material additive can be determined to be a "first raw material additive soluble in the supercritical fluid." If the mass of the remaining additive is greater than 40 mg, the raw material additive can be determined to be a "second raw material additive insoluble in the supercritical fluid." The first raw material additive preferably has a residual mass of 30 mg or less. The second raw material additive preferably has a residual mass of 45 mg or more.

[0053] Examples of the first raw material additive include nucleating agents, plastic decomposition inhibitors, surfactants, plasticizers, flame retardants, antistatic agents, colorants, lubricants, reinforcing agents, anti-fogging agents, and antibacterial agents, but the first raw material additive must be soluble in the supercritical fluid.

[0054] Nucleating agents serve to promote the formation of crystal nuclei during resin crystallization, or to act as crystal nuclei themselves. Examples of nucleating agents include metal salts of phosphate esters, metal salts of aromatic carboxylic acids, metal salts of pieric acid, metal salts of rosin, amide compounds, benzylidene sorbitol, quinacridone, and cyanine blue.

[0055] A plastic decomposition inhibitor is a stabilizer that prevents deterioration of a resin molded product due to heat, light, oxidation, etc. during or after molding processing. Examples of plastic decomposition inhibitors include antioxidants, light stabilizers, and heat stabilizers.

[0056] Examples of antioxidants include phosphorus-based, phenol-based, and thioether-based ones. Examples of light stabilizers include hindered amine-based, benzotriazole-based, and triazine-based ones. Examples of heat stabilizers include oxalic acid compounds, amide compounds such as salicylic acid, and hydrazide compounds.

[0057] As the surfactant, for example, an anionic surfactant, a nonionic surfactant, or lecithin can be used. Anionic surfactants include, for example, N-lauroyl sarcosine or Aerosol (registered trademark) OT. Nonionic surfactants include, for example, condensates of polyoxyethylene and polyoxypropylene, or glycerin fatty acid esters. Lecithin exists in living organisms, for example, and constitutes cell membranes, etc. Two or more types of raw material additives may be used as the first raw material additive.

[0058] The average particle size of the first raw material additive is, for example, 0.5 μm or more. In another example, the average particle size of the first raw material additive is 2 μm or more. The average particle size of the first raw material additive is preferably in the range of 0.5 μm to 20,000 μm, more preferably in the range of 1 μm to 10,000 μm, and even more preferably in the range of 2 μm to 10,000 μm. When a particulate second raw material additive is used, a non-particulate first raw material additive, such as a liquid, can also be used.

[0059] In this specification, the term "particle size" refers to the length of the long side of the smallest rectangle circumscribing a particle present in an image of a particle observed by an electron microscope, and the term "average particle size" refers to the average value of the particle sizes of multiple particles.

[0060] Examples of the second raw material additive include nucleating agents, plastic decomposition inhibitors, plasticizers, flame retardants, antistatic agents, colorants, lubricants, reinforcing agents, anti-fogging agents, and antibacterial agents, but the second raw material additive must be an additive that is insoluble in the supercritical fluid.

[0061] Examples of nucleating agents include fatty acid metal salts, rosin metal salt-based nucleating agents, talc, sorbitol-based nucleating agents, nonitol-based nucleating agents, amide-based nucleating agents, phosphate metal salts, and aromatic carboxylic acid metal salts.

[0062] Examples of plastic decomposition inhibitors include antioxidants, light stabilizers, and heat stabilizers.

[0063] Examples of antioxidants include phenol-based antioxidants, thioether-based antioxidants, and phosphorus-based antioxidants. Examples of light stabilizers include hindered amine-based light stabilizers, benzotriazole-based light stabilizers, and triazine-based light stabilizers. Examples of heat stabilizers include metal soaps, organotin-based stabilizers, and lead-based stabilizers.

[0064] The second raw material additive may be porous, and examples of the porous second raw material additive that can be used include porous silica particles. Two or more types of raw material additives may be used as the second raw material additive.

[0065] The average particle size of the second raw material additive is, for example, 0.5 μm or more, preferably 1 μm or more, more preferably 4 μm or more, and even more preferably 5 μm or more. The average particle size of the second raw material additive is preferably in the range of 0.5 to 20,000 μm, more preferably 1 to 10,000 μm, even more preferably 4 to 10,000 μm, and even more preferably 5 to 10,000 μm.

[0066] In the above-described method, a third feed additive comprising the first and second feed additives is treated with a supercritical fluid. Preferably, the third feed additive consists of the first and second feed additives.

[0067] The average particle size of the third raw material additive is, for example, 0.5 μm or more, preferably 1 μm or more, and more preferably greater than 5 μm. The average particle size of the third raw material additive is preferably in the range of 0.5 μm to 20,000 μm, and more preferably in the range of 5 μm to 1,000 μm.

[0068] The ratio M1 / M2 of the mass M1 of the first raw material additive to the mass M2 of the second raw material additive is preferably in the range of 0.05 to 0.95, more preferably in the range of 0.1 to 0.9.

[0069] In the method for producing an additive for a resin molded product according to this embodiment, a slow expansion method (SESS (Slow Expansion of Supercritical Solutions)) can be used. In the slow expansion method, a high-pressure fluid containing a supercritical fluid and the above-mentioned third raw material additive is decompressed in a pressure-resistant vessel to obtain additive fine particles in the pressure-resistant vessel. This method makes it possible to easily obtain additive fine particles having a small average particle size. There is no need to use a special organic solvent or dispersant. This method will be described below.

[0070] The slow expansion method can be carried out, for example, in a production apparatus equipped with a pressure vessel and a stirring blade installed therein. The production apparatus may further include a temperature control device including at least one of a cooling device and a heating device.

[0071] The additive can be produced using this production apparatus, for example, by stirring a fluid containing a supercritical fluid and a third raw material additive with a stirring blade in a pressure vessel, and then reducing the pressure.

[0072] In this method, the amount of supercritical fluid relative to 100 parts by weight of the third raw material additive can be, for example, within the range of 100 to 1,000,000 parts by weight, preferably 200 to 100,000 parts by weight.

[0073] The treatment using a supercritical fluid in a pressure vessel can be carried out under a pressure of, for example, 7.2 to 100 MPa, preferably 10 to 80 MPa, at a temperature of, for example, 32 to 250°C, preferably 35 to 200°C.

[0074] The stirring time can be, for example, within a range of 5 minutes to 24 hours, preferably 10 minutes to 2 hours, and the stirring speed can be, for example, within a range of 100 to 10,000 rpm, preferably 200 to 1,000 rpm.

[0075] As mentioned above, the supercritical fluid is preferably carbon dioxide, which becomes a supercritical fluid under conditions of 31° C. or higher and 7.4 MPa or higher.

[0076] The decompression rate is, for example, in the range of 0.005 to 15 MPa / s, preferably in the range of 0.01 to 10 MPa / s. Furthermore, in this method, the particle size of the additive can be controlled by changing the decompression rate. For example, when at least one of the first and second raw material additives is a nucleating agent, it is also possible to control the crystallinity.

[0077] The second raw material additive is in the form of an agglomerate formed by the aggregation of a large number of primary particles. A supercritical fluid has a density close to that of a liquid and a diffusion coefficient close to that of a gas. Therefore, when the slow expansion method is used, the supercritical fluid penetrates into the gaps between the large number of primary particles that make up the agglomerate, separating at least some of the bonded primary particles from each other. As a result, the agglomerate can be broken down into smaller particles, for example, into primary particles.

[0078] In the above-mentioned method, an additive that has been reduced to small particles (e.g., an additive that has been reduced to primary particles) may be obtained immediately after the treatment using the supercritical fluid. Alternatively, in the above-mentioned method, the second raw material additive may change to a brittle aggregate state in which the bonds between primary particles are weakened immediately after the treatment using the supercritical fluid, and may change to small particles (e.g., primary particles) when an external force is applied in a subsequent step (e.g., a kneading step with a raw material resin).

[0079] Under the above conditions, the entire amount of the first raw material additive does not have to be dissolved in the supercritical fluid. Furthermore, the treatment using the supercritical fluid in the pressure vessel may be carried out under stirring as necessary. The stirring speed and stirring time can be appropriately set.

[0080] The above-described method can produce additive microparticles having a smaller average particle size than the third raw additive. The additive microparticles can have an average particle size of, for example, 5000 nm or less. This average particle size is preferably in the range of 1 to 5000 nm, and more preferably in the range of 1 to 3000 nm. Furthermore, the above-described method can produce additive microparticles having an average particle size of, for example, 1 to 99%, preferably 1 to 90%, of the average particle size of the third raw additive.

[0081] For example, the additive fine particles can be a resin molding additive containing a first additive soluble in a supercritical fluid and a second additive insoluble in the supercritical fluid, the average particle size of the resin molding additive being 5000 nm or less. Here, the first additive is an additive derived from the first raw material additive obtained by decompressing a fluid containing a supercritical fluid and a third raw material additive containing the first and second raw material additives. The second additive is an additive derived from the second raw material additive obtained by decompressing a fluid containing a supercritical fluid and a third raw material additive containing the first and second raw material additives.

[0082] In one example, composite particles are obtained as a resin molding additive, which include particles of a second additive derived from a second raw material additive and a first additive derived from a first raw material additive supported on particles of the second additive.

[0083] For example, when a surfactant or the like is used as the first raw material additive, composite particles containing particles of the second additive and the first additive coating the surfaces of the particles of the second additive are obtained. In this case, the second feed additive is preferably a nucleating agent.

[0084] Furthermore, when a porous second raw material additive is used, composite particles are obtained in which the first raw material additive is supported or impregnated in the pores of the second raw material additive. Even in this case, the surface of the second additive particles may be coated with the first additive.

[0085] In composite particles containing particles of a second additive and a first additive supported on the particles, the ratio M3 / M4 of the mass M3 of the first additive to the mass M4 of the second additive is preferably in the range of 0.001 to 0.3, more preferably in the range of 0.001 to 0.1. For example, by adjusting this ratio, it is possible to adjust the function of the second additive. For example, if the ratio is too large, the second additive may not be able to perform its function. In addition, in the above case, if the ratio is too small, the dispersibility of the composite particles in the resin molded product described below may be reduced.

[0086] The average particle size of the composite particles is, for example, in the range of 1 to 10,000 nm, preferably 1 to 7,000 nm, and more preferably 1 to 5,000 nm.

[0087] According to another example, a mixture containing particles of a first additive and particles of a second additive is obtained as the additive.

[0088] For example, if at least one of a nucleating agent and a plastic decomposition inhibitor is used as the first raw material additive, and at least one of a nucleating agent and a plastic decomposition inhibitor is used as the second raw material additive, the above mixture can be obtained.

[0089] When obtaining the above mixture, according to one example, each of the first raw material additive and the second raw material additive is at least one of a nucleating agent and a plastic decomposition inhibitor.

[0090] The average particle size of the particles of the first additive is preferably less than 2000 nm, more preferably 1500 nm or less, and is, for example, within the range of 1 to 99%, preferably 1 to 80%, more preferably 1 to 50% of the average particle size of the first raw material additive.

[0091] The average particle size of the particles of the second additive is, for example, within the range of 10 to 100,000 nm, preferably 10 to 10,000 nm, more preferably 10 to 5,000 nm. The average particle size of the particles of the second additive is, for example, within the range of 1 to 99%, preferably 1 to 80%, more preferably 1 to 50% of the average particle size of the second raw material additive.

[0092] When the above mixture is obtained as the additive, the average particle size of the additive is preferably in the range of 1 nm to 10,000 nm, more preferably in the range of 1 nm to 5,000 nm.

[0093] <1.4> Effects The additive microparticles obtained by the method described herein have a small average particle size and can be distributed with high dispersity in the resin. Therefore, even a small amount added to the resin can achieve the significant effects required of the additive. Furthermore, there is little variation in the distribution of the additive in the resin or in the transparent resin layer described below. Furthermore, the above-mentioned additive microparticles also have a small particle size variation.

[0094] For example, by producing a microparticulated nucleating agent according to the method described herein and adding it to a transparent resin layer, it is possible to improve the transparency of the transparent resin layer and achieve both high levels of post-processing resistance and scratch resistance.Furthermore, by producing a microparticulated light stabilizer according to the method described herein and adding it to a transparent resin layer, it is possible to improve the weather resistance of the transparent resin layer.

[0095] Furthermore, bleed-out caused by additives in resin molded products is a phenomenon in which the additives aggregate and coarsen over time, resulting in precipitation on the surface of the resin molded product. Therefore, by using the additives microparticulated by this method as additives for resin molded products, bleed-out can be suppressed.

[0096] Furthermore, since this method does not use a dispersant such as phospholipid or an organic solvent, bleeding out due to these remaining in the resin molded product does not occur.

[0097] Furthermore, according to the above-mentioned method, the first raw material additive and the second raw material additive are treated simultaneously with a supercritical fluid, and therefore the first raw material additive adheres to the surface of the second raw material additive, thereby making it possible to improve the solubility of the second raw material additive in the supercritical fluid.

[0098] In the above-mentioned method, when a surfactant is used as the first raw material additive, a masterbatch with excellent dispersibility of the second additive is obtained. Furthermore, since the transparent resin layer obtained using this masterbatch also has excellent dispersibility, when a nucleating agent is used as the second raw material additive, it is possible to achieve high crystallinity and transparency.

[0099] Furthermore, as described above, the additive obtained by this method exerts a significant effect even in a small amount, so that the amount used can be reduced, and therefore bleeding out due to a high concentration of the additive can be prevented.

[0100] In particular, the above-mentioned method reduces the particle size of the second raw material additive, which is in the form of an aggregate formed by aggregating a large number of primary particles, and therefore can microparticulate the second raw material additive without changing its crystal structure.

[0101] <2> Masterbatch The masterbatch according to this embodiment is a masterbatch for use in resin molded products, and resin molded products such as resin layers are manufactured from a resin obtained by kneading this masterbatch with a second raw material resin described below.

[0102] The method for producing a masterbatch according to this embodiment includes obtaining additive particles by the method for producing an additive for resin molded products described above, and kneading a raw material containing the additive particles and a first raw material resin. The masterbatch obtained by this method contains the additive particles and the first raw material resin.

[0103] Various resins can be used as the first raw material resin. Specific examples of the first raw material resin include polyolefin, polycarbonate, polystyrene, acrylic resins such as polymethyl methacrylate (PMMA), acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, polyamides such as nylon 6 and nylon 66, polyacetal, polyphenylene ether, polyesters such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, liquid crystal polymers, polyphenylene sulfide, polyimide, polyamideimide, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyarylate, polyetherimide, fluororesin, polybutylene succinate, and polylactic acid. These resins may be used alone, or blends or alloys of two or more of these may be used.

[0104] Among these resins, for example, polyolefin, polycarbonate and acrylic resin are preferred from the viewpoints of transparency and durability, and polyolefin is preferred from the viewpoints of chemical resistance, durability and moldability.

[0105] In one embodiment, the first raw material resin is a resin (transparent resin) in which the proportion of polyolefin resin is in the range of 90 to 100 mass %.

[0106] Examples of polyolefin resins include polypropylene; polyethylene; polybutene; 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, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 4-ethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hex ... and copolymers of ethylene or alpha-olefins 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.

[0107] The polyolefin resin is preferably a crystalline resin. The polyolefin resin is, for example, a polypropylene resin. The polyolefin resin is preferably a crystalline polypropylene resin.

[0108] 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. Furthermore, in the crystalline polypropylene resin, the polypropylenes may have the same pentad fraction or may be a combination of polypropylenes with different pentad fractions. The crystalline polypropylene resin is preferably a propylene homopolymer having an isotactic pentad fraction (mmmm fraction) of 95% or more, more preferably an isotactic pentad fraction (mmmm fraction) of 96% or more, i.e., a highly crystalline homopolypropylene resin that is a homopolymer.

[0109] Here, the isotactic pentad fraction (mmmm fraction) is calculated from the electromagnetic wave absorption rate (EMR) value obtained by resonating a crystalline polypropylene resin at a predetermined resonance frequency using 13C-NMR (nuclear magnetic resonance) measurements using carbon (C) with a mass number of 13. The pentad fraction is related to the atomic arrangement, electronic structure, and molecular microstructure of the resin. The isotactic pentad fraction of a polypropylene resin is the proportion of a specific arrangement consisting of five propylene units, i.e., an arrangement in which all propylene units have the same configuration, as determined by 13C-NMR measurements. It is used as a measure of crystallinity or stereoregularity. The isotactic pentad fraction is one of the important factors that primarily determine the scratch resistance of the surface. Basically, the higher the isotactic pentad fraction, the higher the crystallinity of the sheet, resulting in improved scratch resistance.

[0110] The first raw resin may contain other resins in addition to the polyolefin resin. The other resins may be any resins that are highly compatible with the polyolefin resin. However, the proportion of the polyolefin resin in the resins contained in the masterbatch is preferably in the range of 90 to 100% by mass, as described above, and more preferably in the range of 95 to 100% by mass.

[0111] The additive particles contained in the masterbatch may be of one type or two or more types. The amount (total amount) of the additives is preferably in the range of 0.01 to 5 parts by mass, more preferably in the range of 0.05 to 3 parts by mass, per 100 parts by mass of the first raw resin. The amount of the additives may be in the range of 0.1 to 12 parts by mass, per 100 parts by mass of the first raw resin. Note that this masterbatch may contain additives other than the additive particles nano-processed by the above method.

[0112] The total proportion of the first raw material resin and the additive fine particles 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.

[0113] In the production of the masterbatch, the third raw material additive is nano-sized by the above-mentioned method for producing an additive for a resin molded product to obtain additive fine particles, and these additive fine particles are kneaded with a raw material containing the above-mentioned first raw material resin. This method makes it possible to obtain a masterbatch in which additive fine particles with small particle size variation are highly dispersed in the first raw material resin.

[0114] The raw material containing the additive fine particles and the first raw material resin is preferably kneaded in the presence of a supercritical fluid, in which the amount of the supercritical fluid per 100 parts by mass of the raw material is preferably in the range of 5 to 20 parts by mass.

[0115] The supercritical fluid may be, for example, carbon dioxide or nitrogen. The supercritical fluid is preferably carbon dioxide. Carbon dioxide becomes a supercritical fluid under conditions of 31.1°C or higher and 7.38 MPa or higher.

[0116] A supercritical fluid has a density close to that of a liquid and a diffusion coefficient close to that of a gas. The supercritical fluid easily impregnates the first raw resin in a molten state. Therefore, the supercritical fluid increases the fluidity of the first raw resin in a molten state.

[0117] If the fluidity of the raw material is low, attempting to sufficiently heat the raw material in an area away from the heater may result in the raw material being heated to an excessively high temperature in an area near the heater. Furthermore, if the fluidity of the raw material is low, a large amount of frictional heat may be generated during kneading. This may result in discoloration of the resin, such as yellowing.

[0118] As described above, kneading in the presence of a supercritical fluid can increase the fluidity of the raw materials. This allows the raw materials to be heated uniformly and reduces the frictional heat generated during kneading. This prevents discoloration of the resin due to exposure to excessively high temperatures.

[0119] Furthermore, the supercritical fluid increases the fluidity of the first raw material resin in a molten state, and therefore the additive particles can be distributed in the first raw material resin with an even higher degree of dispersion.

[0120] The kneading may be carried out in a batch system or a continuous system, and for continuous kneading, for example, a kneading extruder can be used.

[0121] When a kneading extruder is used, for example, the raw materials are fed into the kneading extruder, and a supercritical fluid is supplied to the kneading extruder. Alternatively, the raw materials are fed into the kneading extruder, and a fluid is supplied to the kneading extruder, and a supercritical fluid is generated from the fluid within the kneading extruder. The pressure inside the kneading extruder is higher on the downstream side than on the upstream side. Therefore, a fluid such as a gas can be supplied to the kneading extruder, and the fluid can be converted into a supercritical fluid within the kneading extruder.

[0122] The kneading extruder used has, for example, an inlet for introducing the raw materials, an outlet for discharging a mixture obtained by kneading the raw materials, and a supply port provided between the inlet and the outlet. The 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 than on the upstream side. When the 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 interfering with the introduction of raw materials into the kneading extruder.

[0123] The above kneading is carried out by setting the heater temperature preferably in the range of 180 to 240°C, more preferably in the range of 190 to 230°C. If the heater temperature is set too low, an extremely high pressure may be required to generate or maintain a supercritical state within the device, or in the case of continuous kneading, the fluidity of the raw materials upstream may be insufficient. If the heater temperature is set too high, discoloration of the resin may occur.

[0124] <3> Resin and resin molded products The resin according to the embodiment of the present invention contains the masterbatch and a second raw material resin. This resin can be obtained by kneading the masterbatch obtained by the above-described method for producing a masterbatch with a raw material containing the second raw material resin. A resin molded product such as a resin layer, which will be described later, is manufactured from the resin obtained by this method.

[0125] Various resins can be used as the second raw material resin, and those described above for the first raw material resin used in the masterbatch can be used. The second raw material resin preferably has the same composition as the first raw material resin. For example, the first and second raw material resins may each be transparent resins in which the proportion of polyolefin resin is in the range of 90 to 100% by mass, and preferably are transparent resins of the same composition in which the proportion of polyolefin resin is in the range of 90 to 100% by mass.

[0126] The proportion of the masterbatch in the resin according to this embodiment is preferably in the range of 0.01 to 50% by mass, and more preferably in the range of 0.1 to 20% by mass.

[0127] The resin according to this embodiment can be used to manufacture a resin molded product. That is, the resin molded product can be obtained by molding the resin according to this embodiment. The resin molded product may have any shape. According to one example, the resin molded product is a resin layer, and this resin layer may be a transparent resin layer.

[0128] The resin layer preferably has a tensile modulus of elasticity in the range of 700 to 2000 MPa, more preferably in the range of 800 to 2000 MPa. The resin layer also preferably has a tensile elongation at break of 200% or more. The tensile elongation at break is, for example, 550% or less.

[0129] Here, the tensile elongation at break is a value that represents the elongation when a sample is pulled at a predetermined speed and breaks, and is the length of the sample at break (L) minus the length of the sample before the test (L0), divided by the length of the sample before the test (L0), expressed as a percentage. A sheet or film with an excessively small value is difficult to elongate and is therefore prone to cracking and whitening during post-processing such as V-groove bending.

[0130] The tensile modulus is a value calculated from the slope of the elastic region in which stress and strain are proportional to each other in the stress-strain curve obtained by the above-mentioned test for tensile elongation at break. A sheet or film with an excessively small modulus is too soft and is likely to cause poor appearance due to wrinkles, for example, when attached to a support. A sheet or film with an excessively large modulus is insufficient in flexibility and is likely to cause poor appearance due to wrinkles, for example, due to reduced adhesion to the support.

[0131] According to one example, the resin layer has a thickness in the range of 20 to 250 μm, and according to another example, the resin layer has a thickness in the range of 30 to 150 μm.

[0132] The resin layer may be one that can be handled by itself, or may be one of the layers contained in a laminate described below. The resin layer or laminate can be used for various products such as packaging materials, electronic components, and decorative sheets.

[0133] In one example, the concentration of the additive microparticles in the resin or resin molded product according to this embodiment is in the range of 0.005 to 1.0% by mass. Preferably, the concentration is in the range of 0.01 to 1.0% by mass. The additive microparticles can be distributed with high dispersion in the resin or resin molded product, and even a small amount can achieve the significant effects required of the additive. This allows the additive concentration in the resin or resin molded product to be kept low. In this case, it is also possible to prevent bleed-out due to a high concentration of the additive in the resin or resin molded product.

[0134] <4> Laminate The laminate includes the resin layer and one or more other layers. The laminate can be obtained by laminating one or more other layers onto the resin layer. The laminate may include the resin layer in any position. For example, a laminate including three or more layers may include the resin layer as one of the outermost layers or as an intermediate layer. The laminate may include only one or more of the resin layers. Below, a decorative sheet will be described as an example of a laminate.

[0135] FIG. 1 is a cross-sectional view of a decorative material including a decorative sheet according to one embodiment of the present invention.

[0136] The decorative material 11 shown in FIG. 1 includes a substrate B and a decorative sheet 1 attached thereto. Here, the decorative material 11 is a decorative board. The decorative board may be a flat plate, or may be curved or folded. The decorative material 11 may have a shape other than a plate.

[0137] Here, the substrate B is a plate material. The plate material is, for example, a wood board, an inorganic board, a metal plate, or a composite board made of multiple materials. The substrate B may have a shape other than a plate.

[0138] Decorative sheet 1 is an example of a laminate containing a transparent resin layer as the resin layer. Decorative sheet 1 contains base fabric layer 2, design layer 3, transparent resin layer 4, surface protective layer 5, adhesive layer 7, primer layer 6, and concealing layer 8. The design layer 3, adhesive layer 7, transparent resin layer 4, and surface protective layer 5 are provided in this order from the base fabric layer 2 side on the surface of base fabric layer 2 opposite the surface facing substrate B. The concealing layer 8 and primer layer 6 are provided in this order from the base fabric layer 2 side on the surface of base fabric layer 2 facing substrate B. One or more of the design layer 3, surface protective layer 5, primer layer 6, adhesive layer 7, and concealing layer 8 may be omitted. The elements contained in decorative sheet 1 will be described below in order.

[0139] <4.1> Raw fabric layer The raw fabric layer 2 or its material can be selected arbitrarily from, for example, paper, synthetic resin, synthetic resin foam, rubber, nonwoven fabric, synthetic paper, metal foil, and the like.

[0140] Examples of paper include tissue paper, titanium paper, and resin-impregnated paper. Examples of synthetic resins include polyethylene, polypropylene, polybutylene, polystyrene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and acrylic. Examples of 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, and polyurethane. Examples of nonwoven fabrics include organic and inorganic nonwoven fabrics. Examples of metals for the metal foil include aluminum, iron, gold, and silver.

[0141] When the raw fabric layer 2 contains a synthetic resin, it may further contain inorganic particles. Examples of inorganic particles include particles made of calcium carbonate, talc, or titanium oxide. When the raw fabric layer 2 contains inorganic particles, the non-flammability or flame retardancy of the decorative sheet 1 is improved.

[0142] <4.2> Primer layer When an olefin-based resin is used as the material of the raw fabric layer 2, the surface of the raw fabric layer 2 is often in an inactive state. Therefore, in this case, it is preferable to provide a primer layer 6 between the raw fabric layer 2 and the substrate B. When the raw fabric layer 2 is made of an olefin-based material, the primer layer 6 may be omitted, and the raw fabric layer 2 may be subjected to a surface modification treatment such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, or dichromate treatment in order to improve the adhesion between the raw fabric layer 2 and the substrate B.

[0143] Materials that can be used for the primer layer 6 include, for example, the materials described below for the design layer 3. Since the primer layer 6 is applied to the back surface of the decorative sheet 1, and considering that the decorative sheet 1 will be wound up in web form, an inorganic filler may be added to the primer layer 6 to avoid blocking and increase adhesion to the adhesive. Examples of inorganic fillers include silica, alumina, magnesia, titanium oxide, and barium sulfate.

[0144] <4.3> Hidden layer To impart the decorative sheet 1 with the ability to conceal the substrate B, for example, a colored sheet can be used as the base layer 2, or an opaque concealing layer 8 can be provided. The concealing layer 8 can be made of, for example, the same material as that used for the design layer 3, which will be described later. However, since the purpose of the concealing layer 8 is to provide concealment, it is preferable to use, for example, an opaque pigment, titanium oxide, iron oxide, or the like, as the pigment. Furthermore, to enhance the concealing ability, metals such as gold, silver, copper, and aluminum can also be added to the material of the concealing layer 8. Generally, flake-shaped aluminum pieces are often added.

[0145] <4.4> Picture layer The design layer 3 is a layer formed by printing a design onto the base layer 2 using ink. Examples of ink binders include soluble nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyesters, and modified products thereof, either alone or in combination. The binder may be aqueous, solvent-based, or emulsion-based, and may be either a one-component type or a two-component type that includes a curing agent. The design layer 3 may be formed by curing a layer formed with a curable ink by exposure to ultraviolet light, electron beams, or the like. The most common method is to use a urethane-based ink that is cured with an isocyanate. The ink used to form the design layer 3 may further contain, in addition to the binder, pigments, colorants such as dyes, extender pigments, solvents, and various additives, which are commonly found in inks. Examples of versatile pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and pearl pigments such as mica.

[0146] In addition to applying 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 be added to the ink. This can suppress deterioration of the decorative sheet 1 itself caused by light degradation of the ink, and extend the life of the decorative sheet 1.

[0147] <4.5>Adhesive layer The adhesive layer 7 is also called a heat-sensitive adhesive layer, an anchor coat layer, or a dry lamination adhesive layer.

[0148] The resin material for the adhesive layer 7 is not particularly limited, and may be appropriately selected from acrylic, polyester, polyurethane, epoxy, and other resin materials. Alternatively, an ethylene-vinyl acetate copolymer resin adhesive may be used as the resin material for the adhesive layer 7. The coating method may be appropriately selected depending on the viscosity of the adhesive. Generally, gravure coating is used, and the adhesive layer 7 is formed on the upper surface of the design layer 3 by gravure coating, followed by lamination of the transparent resin layer 4. The adhesive layer 7 may be omitted if sufficient adhesive strength is obtained between the transparent resin layer 4 and the design layer 3.

[0149] <4.6>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. The upper surface of the transparent resin layer 4 may be provided with an uneven structure. Methods for providing an uneven structure on the upper surface of the transparent resin layer 4 include, for example, a method of applying heat and pressure while pressing an embossing plate against the upper surface of the transparent resin layer 4 that has been laminated to another layer by various methods, and a method of using a cooling roll having an uneven structure on its 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 further improve the design by filling the recesses with ink.

[0150] <4.7>Surface protective layer The surface protective layer 5 is a colorless and transparent resin layer. Here, an uneven structure is provided on the upper surface of the surface protective layer 5. The upper surface of the surface protective layer 5 may also be flat.

[0151] The surface protection layer 5 contains a cured resin. This resin is, for example, a thermosetting resin, an ionizing radiation curable resin, or a combination thereof. The resin may be, for example, aqueous, emulsion, solvent-based, or solventless. Here, "ionizing radiation" refers to charged particle beams such as electron beams. Ionizing radiation curable resins are cured by irradiation with ionizing radiation. Ionizing radiation curable resins can also be cured by irradiation with ultraviolet light.

[0152] As the thermosetting resin, a two-component curing urethane-based thermosetting resin is preferably used. Urethane-based thermosetting resins are suitable from the viewpoints of workability, cost, and the cohesive strength of the resin itself. As the urethane-based resin, a resin obtained by reacting an acrylic polyol with an isocyanate may be used. The isocyanate may 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); their derivatives such as adducts, biuret compounds, and isocyanurates; and prepolymers thereof. In consideration of weather resistance, it is preferable to use a material based on hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI), which have a linear molecular structure.

[0153] As the ionizing radiation curable resin, known materials 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 ionizing 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 resins, epoxy acrylate resins, urethane acrylate resins, and acrylic acrylate resins. In particular, it is preferable to use urethane acrylate resins or acrylic acrylate resins, which have good weather (light) resistance. From the viewpoint of workability, it is preferable to cure the ionizing radiation curable resin with active energy rays such as ultraviolet rays or electron beams.

[0154] As the mixture of thermosetting resin and ionizing radiation curable resin, it is preferable to use a mixture of a urethane resin as a thermosetting resin obtained by reacting an acrylic polyol with an isocyanate, and a urethane acrylate resin as a photocurable resin, which is particularly advantageous in terms of improving surface hardness, suppressing cure shrinkage, and adhesion to inorganic fine particles.

[0155] The surface protective layer 5 may further include inorganic particles. Examples of the inorganic particles include particles made of alumina, silica, boehmite, iron oxide, magnesium oxide, or diamond. The average particle size of the inorganic particles is, for example, in the range of 1 to 100 μm, and in another example, in the range of 1 to 30 μm.

[0156] The inorganic particle content of the surface protective layer 5 is, for example, in the range of 0.1 to 30 parts by mass, and in another example, in the range of 1 to 20 parts by mass, per 100 parts by mass of the resin component. Inclusion of inorganic particles in the surface protective layer 5 improves its scratch resistance. However, excessively high inorganic particle content may reduce transparency due to the light scattering effect of the inorganic particles, or may result in increased costs.

[0157] The surface protective layer 5 can be formed by a known method. A surface protective layer 5 having an uneven surface on its upper surface can be formed by forming a coating film made of an ionizing radiation-curable resin, followed by a first irradiation step in which the coating film is irradiated with light having a wavelength of 200 nm or less (first radiation), and a second irradiation step in which the coating film is irradiated with ionizing radiation such as an electron beam or ultraviolet light having a longer wavelength than the first radiation as second radiation, in that order. Alternatively, the surface protective layer 5 having an uneven surface on its 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. A surface protective 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. The coating film can be formed by various printing methods such as gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, and ink jet printing, and various coating methods such as roll coating, knife coating, microgravure coating, and die coating. [Example]

[0158] The following describes examples of the present invention.

[0159] <Example 1> (Production of additive fine particles) Additive microparticles were prepared using the slow expansion method described above as follows.

[0160] First, a powdered phosphate metal salt nucleating agent (ADK STAB (registered trademark) NA-11, average particle size 2.67 μm, manufactured by ADEKA Corporation) was prepared as the first raw material additive. It was confirmed in advance according to the procedure described above that NA-11 was soluble in supercritical carbon dioxide.

[0161] Next, lithium myristate as the second raw material additive was synthesized according to the following procedure.

[0162] A stir bar and 9.746 g of myristic acid were placed in a 500 mL beaker and stirred in an oil bath set to 65 °C to melt the myristic acid. After melting, 1.794 g of lithium hydroxide monohydrate was gradually added and stirring continued until a free-flowing powder was obtained. The resulting powder was then washed twice with 100 mL of pure water and four times with 100 mL of ethanol. Finally, 100 mL of ethanol was added and the mixture was stirred at 60 °C for 10 minutes. After cooling to room temperature, the solid was collected by suction filtration and vacuum dried to obtain 7.980 g of lithium myristate.

[0163] The insolubility of the obtained lithium myristate in supercritical carbon dioxide was confirmed in advance according to the procedure described in the detailed description. The average particle size of the lithium myristate was 8.9 μm.

[0164] A 500 mL high-pressure stainless steel vessel equipped with a stirring blade was charged with 0.5% (w / v) of the first raw material additive (NA-11) and 0.5% (w / v) of the second raw material additive (lithium myristate) relative to the vessel's volume, sealed, and carbon dioxide was injected to a pressure of 30 MPa at 40°C to create a supercritical state. The mixture was stirred at 300 rpm at 40°C and maintained at 30 MPa for 10 minutes or more. The carbon dioxide was then removed at a rate of 1 MPa / s to reduce the pressure to atmospheric pressure. As a result, a mixture of particles of the first additive with an average particle size of 940 nm and particles of the second additive with an average particle size of 4.8 μm was obtained.

[0165] (Masterbatch manufacturing) A masterbatch containing the above additive fine particles and a polyolefin resin was produced as follows.

[0166] The polyolefin resin used was 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. To this polyolefin resin, 10,000 ppm of the additive particles was added. Other additives included 500 ppm of a hindered phenol antioxidant (Irganox® 1010, manufactured by BASF), 20,000 ppm of a benzotriazole ultraviolet absorber (Tinuvin® 328, manufactured by BASF), and 20,000 ppm of a hindered amine light stabilizer (Chimasorb® 944, manufactured by BASF). The amount in ppm is the mass ratio of each additive based on the total amount of the polyolefin resin and all additives.

[0167] The obtained raw materials were kneaded using a kneading extruder. Here, the heater temperature was set to 230° C. The strands extruded through a strand die were cooled and then cut to obtain a masterbatch.

[0168] (Manufacturing transparent resin sheets) A transparent resin sheet was produced using the masterbatch. Specifically, 10 parts by mass of the masterbatch was added to 100 parts by mass of the same polyolefin resin as used in the production of the masterbatch, and 500 ppm of a hindered phenol-based antioxidant (Irganox (registered trademark) 1010: manufactured by BASF) was further added. The mixture was then extruded using a melt extruder to form a transparent resin sheet having a thickness of 80 μm as a transparent resin layer. Next, both sides of the transparent resin sheet were subjected to a corona treatment to set the surface wetting tension to 40 dyn / cm or more.

[0169] (Decorative sheet manufacturing) A decorative sheet was manufactured using the above transparent resin sheet. Specifically, first, a base fabric layer having a thickness of 70 μm and having hiding properties was prepared. Next, a pattern was printed on one side of the base fabric layer using a two-component curing urethane ink (V180: manufactured by Toyo Ink Co., Ltd.) to form a design layer. A primer coat was applied to the other side of the base fabric layer to form a primer layer. Next, the base fabric layer and the above transparent resin sheet were bonded together by dry lamination so that the design 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 2 g / m 2 Next, the upper surface of the transparent resin sheet was pressed using an embossing die roll to create a concave-convex structure. After that, a two-component curing urethane top coat (W184: manufactured by DIC Graphics Corporation) was applied to the transparent resin sheet at a coating amount of 3 g / m. 2 The coating was then cured to form a surface protective layer. In this way, a decorative sheet having a thickness of 154 μm was obtained.

[0170] <Example 2> In this example, additive particles, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that in the production of the masterbatch, raw materials containing a polyolefin resin and additive particles were kneaded in the presence of supercritical carbon dioxide as shown below. In this example, a mixture of particles of the first additive and particles of the second additive was obtained. The average particle size of the particles of the first additive was 940 nm, and the average particle size of the particles of the second additive was 4.8 μm.

[0171] The raw materials were mixed in the presence of supercritical carbon dioxide as follows. That is, the raw materials containing the polyolefin resin and the additive fine particles were mixed using a kneading extruder equipped with a strand die at the discharge port and a fluid supply device at the intermediate position of the kneading section, while carbon dioxide was supplied from the fluid supply device to the kneading extruder. Here, the heater temperature was set to 230°C, the pressure at the intermediate position of the kneading section was 8 MPa, and the amount of carbon dioxide per 100 parts by mass of raw materials was 6 parts by mass. The strands discharged through the strand die were cooled and then cut to obtain a masterbatch.

[0172] <Example 3> In this example, additive microparticles, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that in the additive microparticle production process, instead of using lithium myristate, a rosin metal salt-based nucleating agent (Pine Crystal (registered trademark) KR-50M, average particle size: 4.4 μm, Arakawa Chemical Industries Co., Ltd.) was used as the second raw material additive. In this example, a mixture of particles of the first additive and particles of the second additive was obtained. The average particle size of the particles of the first additive was 940 nm, and the average particle size of the particles of the second additive was 3.5 μm.

[0173] It was previously confirmed that Pine Crystal (registered trademark) KR-50M is insoluble in supercritical carbon dioxide according to the procedure described in the detailed description.

[0174] <Example 4> In this example, additive microparticles, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that a phosphorus-based antioxidant (Irgafos (registered trademark) 168, average particle size 2.49 μm, manufactured by BASF) was used as the first raw material additive instead of the nucleating agent NA-11. In this example, a mixture of particles of the first additive and particles of the second additive was obtained. The average particle size of the particles of the first additive was 580 nm, and the average particle size of the particles of the second additive was 4.8 μm.

[0175] The solubility of Irgafos® 168 in supercritical carbon dioxide was previously confirmed according to the procedure described in the detailed description.

[0176] <Example 5> In this example, additives, master batches, transparent resin sheets, and decorative sheets were produced in the same manner as in Example 1, except that talc (MicroAce (registered trademark) P-3, average particle size: 5.0 μm, manufactured by Nippon Talc Co., Ltd.) was used as the second raw material additive instead of lithium myristate. In this example, a mixture of particles of the first additive and particles of the second additive was obtained. The average particle size of the particles of the first additive was 940 nm, and the average particle size of the particles of the second additive was 4.5 μm.

[0177] It was previously confirmed that MicroAce (registered trademark) P-3 is insoluble in supercritical carbon dioxide according to the procedure described in the detailed description.

[0178] <Example 6> In this example, the nucleating agent NA-11 and a phosphorus-based antioxidant (Irgafos (registered trademark) 168, average particle size 2.49 μm, manufactured by BASF) were used as the first raw material additive, and the amounts of NA-11, Irgafos (registered trademark) 168, and lithium myristate added to the high-pressure stainless steel vessel with a stirring blade were each 0.33% (w / v). Except for this, the additive, master batch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 1. In this example, a mixture of particles of the first additive and particles of the second additive was obtained. The average particle size of the particles derived from NA-11 in the first additive was 940 nm, the average particle size of the particles derived from Irgafos (registered trademark) 168 in the first additive was 580 nm, and the average particle size of the particles of the second additive was 4.8 μm.

[0179] <Example 7> In this example, lithium myristate and a hindered amine light stabilizer (Chimassorb® 2020, average particle size: 1000 μm or more (pellet form), manufactured by BASF) were used as the second raw material additive, and the amounts of NA-11, Chimassorb® 2020, and lithium myristate placed in the high-pressure stainless steel vessel with a stirring blade were each 0.33% (w / v). The additive, masterbatch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 1. In this example, a mixture of particles of the first additive and particles of the second additive was obtained. The average particle size of the particles of the first additive was 940 nm, and the average particle size of the particles derived from lithium myristate in the second additive was 4.8 μm. In addition, in this example, composite particles in which the first additive, NA-11, and the second additive, lithium myristate, were supported on the surface of the second additive, Chimassorb® 2020, were also obtained. The particles of the second additive derived from Chimassorb® 2020 retained their pellet-like shape and had the same average particle size as before treatment with supercritical carbon dioxide, but had changed into a brittle agglomerated state and could easily be converted into powder when external force was applied.

[0180] <Example 8> In this example, instead of the phosphate ester metal salt nucleating agent NA-11, the surfactant N-lauroyl sarcosine (viscous solid, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the first raw material additive, and the amount of N-lauroyl sarcosine placed in the high-pressure stainless steel vessel with a stirring blade was 0.1% (w / v), and the amount of lithium myristate was 0.9% (w / v). Except for this, additive microparticles, master batches, transparent resin sheets, and decorative sheets were produced in the same manner as in Example 1. In this example, composite particles were obtained of the second additive, lithium myristate, and the first additive, N-lauroyl sarcosine, which coated the surface of the lithium myristate. The average particle size of these composite particles was 4.9 μm.

[0181] When the composite particles were observed under an electron microscope, plate-like particles were observed. Since plate-like particles are obtained when lithium myristate is treated with supercritical carbon dioxide, the plate-like particles are thought to be derived from lithium myristate.

[0182] Furthermore, when the composite particles were observed under an electron microscope, the outlines of the plate-like particles were clearer than those of lithium myristate particles obtained when only lithium myristate was treated with supercritical carbon dioxide. This is thought to be because the surface of the lithium myristate was coated with N-lauroyl sarcosine.

[0183] The solubility of N-lauroyl sarcosine in supercritical carbon dioxide was previously confirmed according to the procedure described in the detailed description.

[0184] <Example 9> In this example, instead of the phosphate ester metal salt nucleating agent NA-11, the surfactant poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (L-31, liquid, manufactured by Merck) was used as the first raw material additive, and the amount of L-31 added to the high-pressure stainless steel vessel with a stirring blade was 0.1% (w / v), and the amount of lithium myristate was 0.9% (w / v). Additive microparticles, master batches, transparent resin sheets, and decorative sheets were produced in the same manner as in Example 1. In this example, composite particles were obtained from the second additive, lithium myristate, and the first additive, L-31, which coated the surface of the lithium myristate. The average particle size of these composite particles was 4.9 μm.

[0185] Similar to the composite particles of Example 8, the contours of the composite particles of Example 9, when observed under an electron microscope, appeared clearer than the contours of lithium myristate particles obtained when only lithium myristate was treated with supercritical carbon dioxide. Therefore, similar to the composite particles of Example 8, it is believed that the surfaces of the lithium myristate of the composite particles of Example 9 are coated with a surfactant.

[0186] The solubility of L-31 in supercritical carbon dioxide was previously confirmed according to the procedure described in the detailed description.

[0187] <Example 10> In this example, an additive, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that the amount of additive fine particles in the production of the masterbatch was changed from 10,000 ppm to 100,000 ppm.

[0188] <Example 11> In this example, an additive, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that the amount of additive fine particles in the production of the masterbatch was changed from 10,000 ppm to 50,000 ppm.

[0189] <Example 12> In this example, an additive, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that the amount of additive fine particles in the production of the masterbatch was changed from 10,000 ppm to 1,000 ppm.

[0190] <Comparative Example 1> In this example, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 1, except that the additive fine particle production process was omitted and NA-11 as the first raw material additive and lithium myristate as the second raw material additive were used instead of the additive fine particles in the masterbatch production process.

[0191] <Comparative Example 2> In this example, the master batch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 3, except that the additive fine particle production process was omitted and NA-11 was used as the first raw material additive and Pine Crystal (registered trademark) KR-50M was used as the second raw material additive instead of the additive fine particles in the master batch production process.

[0192] <Comparative Example 3> In this example, the master batch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 4, except that the additive fine particle production process was omitted and Irgafos (registered trademark) 168 was used as the first raw material additive and lithium myristate as the second raw material additive instead of the additive fine particles in the master batch production process.

[0193] <Comparative Example 4> In this example, the master batch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 5, except that the additive fine particle production process was omitted and NA-11 was used as the first raw material additive and MicroAce (registered trademark) P-3 was used as the second raw material additive instead of the additive fine particles in the master batch production process.

[0194] <Comparative Example 5> In this example, the master batch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 6, except that the additive fine particle production process was omitted and NA-11 and Irgafos (registered trademark) 168 were used as the first raw material additive and lithium myristate as the second raw material additive instead of the additive fine particles in the master batch production process.

[0195] <Comparative Example 6> In this example, the master batch, transparent resin sheet, and decorative sheet were produced in the same manner as in Example 7, except that the additive fine particle production process was omitted and NA-11 was used as the first raw material additive and lithium myristate and Chimassorb (registered trademark) 2020 were used as the second raw material additive instead of the additive fine particles in the master batch production process.

[0196] <Comparative Example 7> In this example, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 8, except that the additive fine particle production process was omitted and N-lauroyl sarcosine as the first raw material additive and lithium myristate as the second raw material additive were used instead of the additive fine particles in the masterbatch production process.

[0197] <Comparative Example 8> In this example, a masterbatch, a transparent resin sheet, and a decorative sheet were produced in the same manner as in Example 9, except that the additive fine particle production process was omitted and L-31 was used as the first raw material additive and lithium myristate was used as the second raw material additive instead of the additive fine particles in the masterbatch production process.

[0198] <Evaluation of additives> (Evaluation of particle size) The additives produced in Examples 1 to 12 and the first and second raw material additives used to produce the masterbatches in Comparative Examples 1 to 8 were observed using an electron microscope SU8020 (Hitachi High-Tech).

[0199] First, the additive, the first raw material additive, or the second raw material additive was placed on a carbon support tape. Then, the additive, the first raw material additive, or the second raw material additive was platinum-coated. This prepared a sample for electron microscope observation. The prepared sample was placed in an observation chamber. Observation was performed at a magnification of 5000 times, and an image of the portion of the observation screen where the additive fine particles, the first raw material additive, or the second raw material additive accounted for 75% or more was saved. Then, a 100 μm 2 The particle diameters of all particles within the range were measured and the average value was calculated. 2 When there are fewer than 30 particles within the range, the observation range is reduced to 100 μm. 2 The particle size of 30 or more particles was measured by spreading the sample in an electron microscope.

[0200] In the obtained images, it was possible to distinguish the first raw material additive and the second raw material additive based on their shapes in Examples 1 to 7 and Comparative Examples 1 to 6. In Example 6, it was possible to distinguish NA-11 and Irgafos (registered trademark) 168 as the first additive and lithium myristate as the second additive based on their shapes. In Comparative Example 5, it was also possible to distinguish NA-11 and Irgafos (registered trademark) 168 as the first raw material additive and lithium myristate as the second raw material additive based on their shapes.

[0201] In addition, in Example 7, the second additive derived from Chimassorb (registered trademark) 2020 was in the form of pellets, so the average particle size of this second additive was not measured.

[0202] <Evaluation of transparent resin sheets> (Evaluation of bleed-out properties) The transparent resin sheet was left at room temperature for one week after production. Two 5 cm x 5 cm pieces were then cut from the transparent resin sheet. One of the pieces was placed in an oven at 80°C ± 3°C and heated for one hour. The remaining piece was not heated. These sheets were immersed in 10 mL of methanol for 15 minutes to extract or disperse the additives that had bled out onto the surface of the sheet into the methanol. This methanol solution was quantitatively analyzed using high-performance liquid chromatography (HPLC). The amounts of additives or their decomposition products (hereinafter also referred to as bleed-out amounts) were analyzed for both the heated and unheated sheets. Based on the results of the HPLC analysis, a heated sheet with a bleed-out amount of 1.5 times or more that of the unheated sheet was evaluated as "bleed-out present," while a heated sheet with a bleed-out amount of less than 1.5 times was evaluated as "no bleed-out present."

[0203] In the case of transparent resin sheets manufactured using talc as the second raw material additive (Example 5 and Comparative Example 4), the bleed-out property was evaluated as follows. Two small pieces measuring 5 cm x 5 cm were cut from the transparent resin sheet, and one of the small pieces was placed in an oven at 80°C ± 3°C and heated for 1 hour. The remaining small piece was not heated. These sheets were not extracted into methanol, and Fourier transform infrared spectroscopy (FT-IR analysis) of the sheet surface was performed using an attenuated total reflectance (ATR) method (Ge prism). This analyzed the amount of talc on the sheet surface. If the amount of talc detected on the heated sheet surface was 1.2 times or more compared to the unheated sheet, it was evaluated as "bleed-out present," and if it was less than 1.2 times, it was evaluated as "bleed-out absent."

[0204] (Tensile test) Test specimens for tensile testing were cut from the transparent resin sheet using a Super Dumbbell Cutter (manufactured by Dumbbell Co., Ltd.) conforming to JIS K7127 Type 4 test specimens. The obtained test specimens were set in a tensile testing machine (manufactured by Tensilon Co., Ltd.) and pulled at a pulling rate of 50 mm / min. The ratio of the length of the test specimen just before it broke to the length before the test was calculated as the tensile breaking elongation. Furthermore, the tensile modulus was calculated from the slope of the stress-strain curve obtained in the test in the elastic region where stress and strain are proportional.

[0205] (Haze value measurement test) The haze value referred to here is a value obtained by subtracting the ratio of the amount of parallel transmitted light, which is the sum of the amount of linear components of the light rays emitted from one side of an object, to the amount of total incident light (parallel transmittance), from the ratio of the total transmitted light, which is the sum of the amount of all light rays emitted from the other side of the object, to the amount of total incident light (total transmittance), when light emitted from an incandescent light source is incident on one side of the object, and dividing the result (diffuse transmittance) by the total light transmittance, expressed as a percentage. The smaller the haze value of an object, the higher the transparency of the object.

[0206] The haze value of an object made of a transparent resin is determined by internal haze, which depends on the internal state of the object, such as the degree of crystallinity in the crystalline portion and the size of the spherulite, and external haze, which depends on the surface state of the object, such as the presence or absence of irregularities on the entrance and exit surfaces. In this specification, when simply referring to the haze value, it means a value determined by the internal haze and external haze.

[0207] Here, the haze value measurement test was performed on each transparent resin sheet using a haze value measurement tester (NDH2000: manufactured by Nippon Denshoku Industries Co., Ltd.). Specifically, first, a blank measurement was performed with nothing attached to the sample holder. Next, a sample transmittance measurement was performed with the transparent resin sheet attached to the sample holder as a sample. Then, the ratio of the value obtained by the sample transmittance measurement to the value obtained by the blank measurement was calculated as a percentage, and the haze value was calculated from these transmittances.

[0208] <Evaluation of decorative sheets> (Pencil hardness test) Pencils with lead hardnesses of 2B, B, HB, F, H, 2H, and 3H were prepared. Next, the tip of the pencil lead was placed against the upper surface of the surface protection layer of the decorative sheet, and the angle formed by the pencil's longitudinal direction was fixed at 45±1°. The pencil was then slid with a load of 1 kg applied to determine whether scratches were formed on the decorative sheet (in accordance with the old JIS standard JISK5400). The test was performed in ascending hardness order using pencils, and the hardness at which a scratch was first formed was taken as the surface hardness of the decorative sheet.

[0209] (V-groove bending process suitability test) A medium-density fiberboard (MDF) was prepared as the substrate. Next, a decorative sheet was attached to one side of the substrate using a urethane adhesive to produce a decorative material. Next, a groove with a V-shaped cross section (V-groove) was formed on the other side of the substrate attached to the substrate. This V-groove was formed so that its bottom reached the boundary between the substrate and the decorative sheet and so as not to scratch the decorative sheet. Next, the decorative material was folded at a 90° angle along the V-groove so that the decorative sheet side formed a mountain fold. The mountain fold of the decorative sheet was then observed with an optical microscope to check for defects such as whitening or cracks at the mountain fold, and post-processability was evaluated according to the following criteria. A: No defects such as whitening or cracks were observed. B: Defects such as whitening and cracks were observed.

[0210] (weather resistance) A carbon arc weather resistance test was conducted in accordance with JIS B 7753 using a weather resistance tester (Sunshine Weather Meter, manufactured by Suga Test Instruments Co., Ltd.). The test conditions were a weather resistance time of 4000 hours. The change in appearance of each transparent resin film before and after the weather resistance test was evaluated based on the following criteria. Evaluation B indicates that the film satisfies the weather resistance required for applications such as decorative sheets. A: No change at all B: No whitening or cracks, but some loss of gloss and slight fading C: Whitening, cracks, or partial destruction or breakage. <Evaluation results> The results of the above evaluations are summarized in Tables 1 to 8.

[0211] [Table 1]

[0212] [Table 2]

[0213] [Table 3]

[0214] [Table 4]

[0215] [Table 5]

[0216] [Table 6]

[0217] [Table 7]

[0218] [Table 8]

[0219] In Tables 1 to 8, for Comparative Examples 1 to 8, masterbatches were produced using first and second raw material additives instead of additive microparticles, so the "average particle size (μm)" column shows the average particle size of each raw material additive. In Tables 1 to 8, the "A1" column in the "average particle size [μm]" column shows the average particle size of the first raw material additive listed in the "A1" column in the "First Raw Material Additive" column, the "A2" column shows the average particle size of the first raw material additive listed in the "A2" column in the "First Raw Material Additive" column, and the "B1" column shows the average particle size of the second raw material additive listed in the "B1" column in the "Second Raw Material Additive" column.

[0220] As shown in Table 2, additives with small average particle sizes were obtained by the above-described method. Furthermore, as shown in Tables 3 and 4, when transparent resin sheets were produced using the additive microparticles obtained by the above-described method, bleed-out of the additive microparticles was eliminated. Furthermore, the haze of the transparent resin sheet was reduced, and the tensile modulus and tensile elongation at break of the transparent resin sheet were increased. This is thought to be due to the fact that the additive microparticles were refined, thereby improving the dispersion of the additive within the plane of the transparent resin sheet. Furthermore, as shown in Tables 3 and 4, when decorative sheets were produced using the additive microparticles obtained by the above-described method, the decorative sheets were able to achieve both excellent scratch resistance and excellent post-processability. Furthermore, as shown in Table 4, the decorative sheets of Examples 4, 6, and 7, which contained a plastic decomposition inhibitor as the first additive, had excellent weather resistance.

[0221] Furthermore, as described above, in Example 7, the particles of the second additive derived from Chimassorb® 2020 maintained their pellet-like shape and had the same average particle size as before treatment with supercritical carbon dioxide, but they had changed into a brittle aggregate state and could easily be converted into powder when external force was applied. Furthermore, in Example 7, composite particles were obtained in which the first additive, NA-11, and the second additive, lithium myristate, were supported on the surface of the second additive, Chimassorb® 2020. Therefore, in the production of the masterbatch of Example 7, the composite particles were easily converted into powder and then uniformly mixed with additives other than the composite particles in Example 7. Therefore, it is believed that the decorative sheet of Example 7 had excellent hardness, post-processability, and weather resistance.

[0222] Furthermore, compared to Example 1, in which no supercritical fluid was injected during the production of the masterbatch, Example 2, in which a supercritical fluid was injected, had a higher haze and better transparency in the transparent resin layer. This shows that producing the masterbatch in the presence of a supercritical fluid allows the nucleating agent particles to be distributed in the resin with a higher degree of dispersion without agglomeration, thereby reducing the haze in the transparent resin layer and improving transparency. [Explanation of symbols]

[0223] 1...decorative sheet, 2...base layer, 3...pattern layer, 4...transparent resin layer, 5...surface protection layer, 6...primer layer, 7...adhesive layer, 8...hiding layer, 11...decorative material, B...base material.

Claims

1. A method for producing an additive for a resin molded product, comprising: reducing the pressure of a fluid containing a supercritical fluid and a third raw material additive, the third raw material additive including a first raw material additive soluble in the supercritical fluid and a second raw material additive insoluble in the supercritical fluid, to obtain an additive having a smaller average particle size than the third raw material additive.

2. 2. The method for producing an additive for a resin molded product according to claim 1, further comprising obtaining composite particles containing, as the additive, particles of a second additive derived from the second raw material additive and a first additive derived from the first raw material additive supported on particles of the second additive.

3. 3. The method for producing an additive for a resin molded product according to claim 2, wherein the first additive coats the surfaces of particles of the second additive.

4. 4. The method for producing an additive for a resin molded product according to claim 3, wherein the first raw material additive is a surfactant.

5. 4. The method for producing an additive for a resin molded product according to claim 3, wherein the second raw material additive is a nucleating agent.

6. 3. The method for producing an additive for a resin molded product according to claim 2, wherein the second raw material additive is porous.

7. 2. The method for producing an additive for a resin molded product according to claim 1, further comprising obtaining a mixture containing particles of a first additive derived from the first raw material additive and particles of a second additive derived from the second raw material additive as the additive.

8. 8. The method for producing an additive for a resin molded product according to claim 7, wherein each of the first raw material additive and the second raw material additive is at least one of a nucleating agent and a plastic decomposition inhibitor.

9. 2. The method for producing an additive for a resin molded product according to claim 1, wherein the average particle size of the third raw material additive is 2 μm or more, and the additive obtained has an average particle size of 5000 nm or less.

10. 2. The method for producing an additive for a resin molded product according to claim 1, wherein the supercritical fluid comprises carbon dioxide.

11. 2. The method for producing an additive for a resin molded product according to claim 1, wherein the fluid is decompressed in a pressure-resistant container.

12. Producing the additive by the method for producing an additive for a resin molded product according to any one of claims 1 to 11; kneading a raw material containing a first raw material resin and the additive; A method for producing a masterbatch comprising:

13. The method for producing a masterbatch according to claim 12, wherein the raw materials are kneaded in the presence of a supercritical fluid.

14. The method for producing a masterbatch according to claim 12, wherein the first raw material resin is a resin in which the proportion of polyolefin resin is in the range of 90 to 100 mass %.

15. Producing the masterbatch by the method for producing the masterbatch according to claim 12; kneading a raw material containing the masterbatch and a second raw material resin; A method for producing a resin comprising the steps of:

16. The method for producing a resin according to claim 15, wherein the first raw resin and the second raw resin are each independently a resin having a polyolefin resin content in the range of 90 to 100% by mass.

17. Producing the resin by the resin producing method according to claim 15; molding the resin to produce a resin molded product; A method for manufacturing a resin molded product comprising the steps of:

18. The method for producing a resin molded product according to claim 17, wherein the concentration of the additive in the resin molded product is set to be within a range of 0.005 to 1.0 mass %.

19. The method for producing a resin molded product according to claim 17, wherein the resin molded product is a resin layer.

20. forming the resin layer by the method for producing a resin molded product according to claim 19; laminating one or more other layers on the resin layer; A method for producing a laminate comprising the steps of:

21. The method for producing a laminate according to claim 20, wherein the laminate is a decorative sheet.

22. An additive for resin molding products, comprising a first additive soluble in a supercritical fluid and a second additive insoluble in the supercritical fluid, The additive for resin molding products has an average particle size of 5000 nm or less.

23. A masterbatch comprising the additive for resin molding according to claim 22 and a first raw resin.

24. A resin comprising the masterbatch according to claim 23 and a second raw resin.

25. A resin molded product obtained by molding the resin according to claim 24.

26. A laminate comprising a resin layer obtained by forming the resin according to claim 24 and one or more other layers provided on the resin layer.

Images