Reflective film

Abstract

This reflective film (X) is provided with a base film (10), a metal reflective layer (20), and a cured resin layer (50) in this order in the thickness direction (H). The water contact angle of the outer surface (51) of the cured resin layer (50) on the opposite side from the metal reflective layer (20) is 80 DEG or less. The dynamic friction coefficient of the outer surface (51) with respect to the polyethylene terephthalate film is 0.23 or less.

Description

Technical Field

[0001] The invention relates to a reflective film. Background Art

[0002] The liquid crystal display device comprises: a liquid crystal panel having an image display surface; a backlight source emitting light toward the back of the panel; and a housing accommodating the liquid crystal panel and the backlight source. The housing has a frame portion as a frame surrounding the image display surface. A reflective film is arranged on the inner wall surface of the frame portion.

[0003] The reflective film has a base film, a metal reflective layer, and a cured resin layer as an overcoat (OC) in order in the thickness direction. The OC side of the reflective film is bonded to the inner wall surface by means of an adhesive, so that the reflective film is installed in the frame portion. The reflective film reflects the light from the backlight source toward the liquid crystal panel by means of the metal reflective layer in the frame portion. Thus, the light from the backlight source is effectively utilized. Such a reflective film is described, for example, in the following patent document 1.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2004-184443

[0007] The OC of the reflective film is required to have good adhesion to the adhesive. In order to improve its adhesion, it is considered to improve the wettability of the OC surface. However, the higher the wettability of the OC surface, the more difficult it is for other components to slide on the OC surface (sliding property decreases) when other components come into contact with the OC surface, and the easier it is to damage the OC surface. Damage to the OC surface will affect the optical properties and corrosion resistance of the reflective film. Summary of the invention

[0008] The present invention provides a reflective film having both adhesion to an adhesive and resistance to scratching on the outer surface of a cured resin layer.

[0009] The present invention [1] includes a reflective film, which comprises a substrate film, a metal reflective layer and a cured resin layer in this order in the thickness direction, wherein the water contact angle of the outer surface of the cured resin layer on the opposite side to the metal reflective layer is less than 80°, and the dynamic friction coefficient of the outer surface relative to a polyethylene terephthalate film is less than 0.23.

[0010] The present invention [2] includes the reflective film described in the above [1], wherein the water contact angle is 50° or more.

[0011] The present invention [3] includes the reflective film described in [1] or [2] above, wherein the dynamic friction coefficient is 0.15 or more.

[0012] The present invention [4] includes the reflective film according to any one of [1] to [3] above, wherein the metal reflective layer is an aluminum layer.

[0013] The present invention [5] includes the reflective film according to any one of [1] to [4], further comprising a metal oxide layer between the metal reflective layer and the cured resin layer.

[0014] The present invention [6] includes the reflective film described in the above [5], wherein the metal oxide layer is an indium tin oxide layer.

[0015] Effects of the Invention

[0016] As described above, the reflective film of the present invention has a water contact angle of 80° or less on the outer surface of the cured resin layer. Thus, wettability can be ensured on the outer surface, and good adhesion to the adhesive can be achieved. In addition, as described above, the reflective film of the present invention has a dynamic friction coefficient of 0.23 or less on the outer surface relative to the polyethylene terephthalate film. Thus, the sliding property of other components when in contact with the outer surface can be ensured, and the outer surface can be protected from damage. Therefore, in the reflective film of the present invention, the cured resin layer as the outermost layer can achieve both adhesion and resistance to damage to the adhesive. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic cross-sectional view of one embodiment of the reflective film of the present invention.

[0018] Figure 2A to Figure 2D express Figure 1 The manufacturing method of the reflective film shown. Figure 2A It represents the process of forming a metal reflective layer on a substrate film. Figure 2B It represents the process of forming a black layer on the metal reflective layer. Figure 2C It represents the process of forming a metal oxide layer on the blackened layer. Figure 2D This shows the step of forming a cured resin layer on the metal oxide layer.

[0019] Figure 3 FIG. 1 is a schematic cross-sectional view of a modification of the reflective film of the present invention. This modification does not have a blackened layer.

[0020] Figure 4 FIG. 1 is a schematic cross-sectional view of another modified example of the reflective film of the present invention. This modified example does not have a metal oxide layer.

[0021] Description of Reference Numerals

[0022] X: reflective film; H: thickness direction; 10: substrate film; 11: first surface; 12: second surface; 20: metal reflective layer; 30: blackened layer; 40: metal oxide layer; 50: cured resin layer; 51: outer surface. DETAILED DESCRIPTION

[0023] like Figure 1 As shown in FIG. 1 , a reflective film X according to an embodiment of the present invention includes a base film 10, a metal reflective layer 20, a blackened layer 30, a metal oxide layer 40, and a cured resin layer 50 in order in the thickness direction H. The reflective film X is extended in a direction (surface direction) orthogonal to the thickness direction H. The reflective film X is, for example, a reflective film that prevents light from a backlight source of a liquid crystal display device from leaking from a housing.

[0024] The substrate film 10 is a substrate that ensures the strength of the reflective film X. The substrate film 10 has a first surface 11 and a second surface 12 on the opposite side of the first surface 11. In addition, the substrate film 10 is, for example, a flexible transparent resin film. As the material of the substrate film 10, for example, polyester resin, polyolefin resin, acrylic resin, polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, cellulose resin and polystyrene resin can be listed. As polyester resin, for example, polyethylene terephthalate (PET), polybutylene terephthalate and polyethylene naphthalate can be listed. As polyolefin resin, for example, polyethylene, polypropylene and cycloolefin polymer can be listed. As acrylic resin, for example, polymethacrylate can be listed. From the viewpoint of transparency and strength, the material of the substrate film 10 is preferably polyester resin, more preferably PET.

[0025] From the viewpoint of ensuring the significant light reflectivity of the substrate film 10, the substrate film 10 is preferably a white film. The white film is obtained, for example, as a resin film with particles such as inorganic fillers that produce light scattering. As such particles, for example, titanium oxide, calcium carbonate, barium sulfate, silicon dioxide and talc can be listed, and at least one selected from the group consisting of titanium oxide and silicon dioxide is preferably used. These particles can be used alone or in combination of two or more. The average particle size (D50) of the particles is, for example, 0.05 μm or more, preferably 0.1 μm or more, and, for example, 2 μm or less, preferably 1 μm or less. The content ratio of the particles in the substrate film 10 as a white film is, for example, 5% by mass or more, preferably 10% by mass or more, and, for example, 50% by mass or less, preferably 40% by mass or less.

[0026] From the viewpoint of suppressing the infiltration of water vapor from the substrate film 10 side of the reflective film X into the metal reflective layer 20 and the blackened layer 30 (suppressing the infiltration of vapor) and from the viewpoint of the strength of the reflective film X, the thickness of the substrate film 10 is preferably 20 μm or more, more preferably 30 μm or more, and further preferably 35 μm or more. From the viewpoint of ensuring the operability of the substrate film 10 in the roll-to-roll method, the thickness of the substrate film 10 is preferably 300 μm or less, more preferably 200 μm or less, and further preferably 150 μm or less. From the viewpoint of taking into account both the above-mentioned suppression of vapor infiltration and strength and the above-mentioned operability, the thickness of the substrate film 10 is preferably 20 to 300 μm, more preferably 30 to 200 μm, and further preferably 35 to 150 μm.

[0027] The first surface 11 of the substrate film 10 may be subjected to a surface modification treatment from the viewpoint of ensuring the adhesion of the metal reflective layer 20 to the substrate film 10. Examples of the surface modification treatment include corona treatment, plasma treatment, ozone treatment, primer treatment, glow treatment, and coupling agent treatment.

[0028] In the present embodiment, the metal reflective layer 20 is disposed on the first surface 11 of the base film 10. That is, in the present embodiment, the metal reflective layer 20 is in contact with the first surface 11.

[0029] The metal reflective layer 20 is formed of a metal having light reflectivity. Examples of the metal forming the metal reflective layer 20 include aluminum (Al), silver (Ag), titanium (Ti), and alloys thereof. From the perspective of ensuring good light reflectivity of the metal reflective layer 20 to visible light, the metal of the metal reflective layer 20 is preferably aluminum or silver. That is, the metal reflective layer 20 is preferably an aluminum layer or a silver layer. More preferably, the metal reflective layer 20 is an aluminum layer.

[0030] From the viewpoint of ensuring the light reflectivity of the metal reflective layer 20 and the reflective film X, the thickness of the metal reflective layer 20 is preferably 30 nm or more, more preferably 50 nm or more, further preferably 60 nm or more, and further preferably 70 nm or more. From the viewpoint of ensuring the adhesion of the metal reflective layer 20 to the base film 10, the thickness of the metal reflective layer 20 is preferably 500 nm or less, more preferably 250 nm or less, further preferably 150 nm or less, and further preferably 120 nm or less. From the viewpoint of taking into account both the above-mentioned light reflectivity and the above-mentioned adhesion, the thickness of the metal reflective layer 20 is preferably 30 to 500 nm, more preferably 50 to 250 nm, further preferably 60 to 150 nm, and further preferably 70 to 120 nm.

[0031] In the present embodiment, the blackened layer 30 is disposed on the metal reflective layer 20 . That is, in the present embodiment, the blackened layer 30 is in contact with the metal reflective layer 20 .

[0032] The black layer 30 is a layer with high light absorption, and in this embodiment, is an inorganic black layer containing a metal compound and a metal element. The black layer 30 may contain multiple metal compounds. The black layer 30 may contain multiple metal elements.

[0033] The metal compound is a compound of a metal and a non-metal. Examples of the metal compound include metal oxides, metal nitrides, and metal carbides. The metal compound is preferably a metal oxide. Examples of the metal (first metal) in the metal compound include indium (In), copper (Cu), molybdenum (Mo), and iron (Fe). The first metal is preferably at least one selected from the group consisting of In, Cu, Mo, and Fe.

[0034] Examples of the metal single substance (second metal) include In, Cu, Mo, and Fe. The metal single substance is preferably at least one selected from the group consisting of In, Cu, Mo, and Fe.

[0035] From the perspective of achieving high light-shielding properties in the black layer 30, the proportion of the first metal in the black layer 30 is preferably 10 atomic % or more, more preferably 20 atomic % or more, and preferably 90 atomic % or less, and more preferably 80 atomic % or less. That is, the proportion of the first metal in the black layer 30 is preferably 10 to 90 atomic %, and more preferably 20 to 80 atomic %. From the perspective of achieving high light-shielding properties in the black layer 30, the proportion of the second metal in the black layer 30 is preferably 10 atomic % or more, more preferably 20 atomic % or more, and preferably 90 atomic % or less, and more preferably 80 atomic % or less. That is, the proportion of the second metal in the black layer 30 is preferably 10 to 90 atomic %, and more preferably 20 to 80 atomic %.

[0036] From the viewpoint of achieving high light-shielding property in the black layer 30, the black layer 30 preferably contains a metal oxide as a metal compound and a metal element, and more preferably contains indium oxide as a metal compound and contains copper as a metal element. When the black layer 30 contains indium oxide and copper, from the viewpoint of achieving high light-shielding property in the black layer 30, the ratio of In in the black layer 30 is preferably 40 atomic % or more, more preferably 50 atomic % or more, and preferably 90 atomic % or less, and more preferably 80 atomic % or less. That is, the ratio of In in the black layer 30 is preferably 40 to 90 atomic %, and more preferably 50 to 80 atomic %. When the black layer 30 contains indium oxide and copper, from the viewpoint of achieving high light-shielding property in the black layer 30, the ratio of Cu in the black layer 30 is preferably 5 atomic % or more, more preferably 10 atomic % or more, and preferably 50 atomic % or less, and more preferably 40 atomic % or less. That is, the ratio of Cu in the black layer 30 is preferably 5 to 50 atomic %, and more preferably 10 to 40 atomic %.

[0037] From the viewpoint of ensuring the light-shielding property of the black layer 30 and the reflective film X, the thickness of the black layer 30 is preferably 5 nm or more, more preferably 10 nm or more, further preferably 20 nm or more, and further preferably 25 nm or more. From the viewpoint of ensuring the adhesion of the black layer 30 to the substrate (the metal reflective layer 20 in this embodiment), the thickness of the black layer 30 is preferably 400 nm or less, more preferably 200 nm or less, further preferably 100 nm or less, and further preferably 50 nm or less. From the viewpoint of taking into account both the above-mentioned light-shielding property and the above-mentioned adhesion, the thickness of the black layer 30 is preferably 5 to 400 nm, more preferably 10 to 200 nm, further preferably 20 to 100 nm, and further preferably 25 to 50 nm.

[0038] From the viewpoint of ensuring the light shielding property of the blackened layer 30 and the reflective film X, the light transmittance (Y value) of the blackened layer 30 at a wavelength of 380 nm to 780 nm in the CIE-XYZ colorimetric system is preferably 0.1% or less, more preferably 0.05% or less, and further preferably 0.03% or less. The light transmittance is, for example, 0.001% or more, 0.005% or more, or 0.01% or more. The light transmittance can be measured, for example, by a spectrophotometer (product name "U-4100", manufactured by Hitachi High-Tech Corporation).

[0039] In this embodiment, the black layer 30 is a film formed by dry coating (dry coating film). Examples of dry coating films include sputtering films formed by sputtering and vapor deposition films formed by vapor deposition. The dry coating film is preferably a sputtering film.

[0040] In the present embodiment, the metal oxide layer 40 is disposed on the blackened layer 30. That is, in the present embodiment, the metal oxide layer 40 is in contact with the blackened layer 30.

[0041] In this embodiment, the metal oxide layer 40 is a barrier layer. The metal oxide layer 40, for example, inhibits water vapor from penetrating from the cured resin layer 50 side into the blackened layer 30 and the metal reflective layer 20. Inhibiting the penetration of water vapor contributes to inhibiting corrosion such as galvanic corrosion of the metal reflective layer 20 and the blackened layer 30.

[0042] Examples of the metal of the metal oxide forming the metal oxide layer 40 include indium (In), zinc (Zn), tin (Sn), magnesium (Mg), nickel (Ni), cobalt (Co), and chromium (Cr). From the viewpoint of ensuring the water vapor barrier property of the metal oxide layer 40, it is preferred that the metal of the metal oxide is at least one selected from the group consisting of In, Zn, Sn, Mg, Ni, Co, and Cr, and it is more preferred that the metal oxide layer 40 is an indium tin oxide (ITO) layer.

[0043] From the viewpoint of ensuring the water vapor barrier property of the metal oxide layer 40, the thickness of the metal oxide layer 40 is preferably 5 nm or more, more preferably 8 nm or more, and further preferably 10 nm or more. From the viewpoint of ensuring the adhesion of the metal oxide layer 40 to the blackened layer 30, the thickness of the metal oxide layer 40 is preferably 200 nm or less, more preferably 150 nm or less, and further preferably 100 nm or less. From the viewpoint of taking into account both the above-mentioned water vapor barrier property and the above-mentioned adhesion, the thickness of the metal oxide layer 40 is preferably 5 to 200 nm, more preferably 8 to 150 nm, and further preferably 10 to 100 nm.

[0044] In the present embodiment, the cured resin layer 50 is disposed on the metal oxide layer 40. That is, in the present embodiment, the cured resin layer 50 is in contact with the metal oxide layer 40. The cured resin layer 50 is an outer coating layer as one of the outermost layers in the thickness direction H of the reflective film X. In addition, the cured resin layer 50 is, for example, a hard coating layer for preventing scratches from being formed on the reflective film X.

[0045] The cured resin layer 50 is a cured product of a curable resin composition. The curable resin composition contains a curable resin. Examples of curable resins include polyester resins, acrylic urethane resins, acrylic resins (excluding acrylic urethane resins), urethane resins (excluding acrylic urethane resins), amide resins, silicone resins, epoxy resins, and melamine resins. These curable resins may be used alone or in combination of two or more. From the perspective of ensuring the high hardness of the cured resin layer 50, the curable resin is preferably selected from at least one of the group consisting of acrylic urethane resins and acrylic resins.

[0046] Examples of the curable resin include ultraviolet curable resins and thermosetting resins. The curable resin is preferably an ultraviolet curable resin because it can be cured without high-temperature heating and thus contributes to improving the production efficiency of the reflective film X.

[0047] From the viewpoint of ensuring the hardness of the cured resin layer 50, the proportion of the curable resin in the cured resin layer 50 (wherein, it is the proportion in the cured resin layer 50 excluding the particles described below. The same applies below) is preferably 95.0% by mass or more, more preferably 97.0% by mass or more, and further preferably 99.0% by mass or more. From the viewpoint of ensuring the proportion of other components in the cured resin layer 50, the proportion of the cured resin layer 50 is preferably 99.9% by mass or less, more preferably 99.7% by mass or less, and further preferably 99.5% by mass or less. From the viewpoint of taking into account both ensuring the above-mentioned hardness and ensuring the proportion of other components, the proportion of the curable resin is preferably 95.0 to 99.9% by mass, more preferably 97.0 to 99.7% by mass, and further preferably 99.0 to 99.5% by mass.

[0048] The cured resin layer 50 preferably contains a leveling agent. That is, the curable resin composition preferably contains a leveling agent. Examples of the leveling agent include silicone-based leveling agents, fluorine-based leveling agents, and acrylic-based leveling agents.

[0049] Examples of silicone leveling agents include alkyl-modified silicone, polyether-modified silicone, polyester-modified silicone, and dimethylpolysiloxane. Examples of commercially available silicone leveling agents include "Polyflow LE303", "Polyflow KL-400X", "Polyflow KL-400HF", "Polyflow KL-401", "Polyflow KL-402", "Polyflow KL-403", and "Polyflow KL-404" manufactured by Kyoeisha Chemical. Examples of commercially available silicone leveling agents include "KP-323", "KP-326", "KP-341", "KP-104", and "KP-110" manufactured by Shin-Etsu Chemical. Commercially available products of the silicone-based leveling agent include "LP-7001", "LP-7002", "8032 ADDITIVE" and "57 ADDITIVE" manufactured by Dow Toray.

[0050] Commercially available products of fluorine-based leveling agents include, for example, "OPTOOL DSX" and "OPTOOL DAC-HP" manufactured by Daikin Industries. Commercially available products of fluorine-based leveling agents also include "Surflon S-242", "Surflon S-243", "Surflon S-420" and "Surflon S-611" manufactured by AGC Seimichemical. Commercially available products of fluorine-based leveling agents also include "AC 110a" and "AC 100a" manufactured by BYK Japan.

[0051] Examples of commercially available products of the acrylic leveling agent include "Polyflow No. 36", "Polyflow No. 56", "Polyflow No. 85HF", and "Polyflow No. 99C" manufactured by Kyoeisha Chemical Co., Ltd.

[0052] As the leveling agent, from the viewpoint of easily achieving a balance between the water contact angle and the dynamic friction coefficient described below, a silicone-based leveling agent is preferred, and an alkyl-modified silicone is more preferred.

[0053] From the viewpoint of reducing the dynamic friction coefficient of the cured resin layer 50 described below, the content of the leveling agent in the cured resin layer 50 is preferably 0.01 parts by mass or more, more preferably 0.02 parts by mass or more, further preferably 0.03 parts by mass or more, and further preferably 0.04 parts by mass or more, relative to 100 parts by mass of the curable resin. From the viewpoint of preventing the water contact angle of the cured resin layer 50 described below from being too large, the content of the leveling agent in the cured resin layer 50 is preferably 0.11 parts by mass or less, more preferably 0.10 parts by mass or less, further preferably 0.09 parts by mass or less, and further preferably 0.08 parts by mass or less, relative to 100 parts by mass of the curable resin. From the viewpoint of taking into account both the dynamic friction coefficient and the water contact angle of the cured resin layer 50, the content of the leveling agent in the cured resin layer 50 is preferably 0.01 to 0.11 parts by mass, more preferably 0.02 to 0.10 parts by mass, further preferably 0.03 to 0.09 parts by mass, and further preferably 0.04 to 0.08 parts by mass, relative to 100 parts by mass of the curable resin.

[0054] The cured resin layer 50 preferably contains particles. That is, the curable resin composition preferably contains particles. The particles may be nanoparticles (nanoscale particles). As particles, for example, inorganic oxide particles and organic particles may be listed. As materials for inorganic oxide particles, for example, silica, alumina, titanium oxide, zirconium oxide, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide may be listed. As materials for organic particles, for example, polymethyl methacrylate, polystyrene, polyurethane, acrylic-styrene copolymer, benzoguanamine, melamine, and polycarbonate may be listed. The particles may be used alone or in combination of two or more. As particles, organic particles are preferably used. As organic particles, polymethacrylate particles are preferably used. As particles, inorganic oxide particles may be used. As inorganic oxide particles, at least one selected from silica particles and zirconium oxide particles is preferably used.

[0055] From the viewpoint of ensuring the sliding property of the cured resin layer 50 by forming irregularities on the surface of the cured resin layer 50 (the outer surface 51 described below), the average particle size (D50) of the particles is preferably 0.5 μm or more, more preferably 1.0 μm or more, further preferably 1.5 μm or more, and further preferably 2.0 μm or more (the presence of the irregularities on the surface reduces the contact area between other components and the outer surface 51, and the sliding property of the other components relative to the outer surface 51 is ensured). From the viewpoint of suppressing optical scattering on the surface of the cured resin layer 50, the average particle size (D50) of the particles is preferably 3.5 μm or less, more preferably 3.0 μm or less, further preferably 2.7 μm or less, and further preferably 2.5 μm or less. From the viewpoint of achieving both the above-mentioned sliding property of the cured resin layer 50 and suppressing optical scattering, the average particle size (D50) of the particles is preferably 0.5 to 3.5 μm, more preferably 1.0 to 3.0 μm, further preferably 1.5 to 2.7 μm, and further preferably 2.0 to 2.5 μm. The average particle size (D50) of particles is the median size in a volume-based particle size distribution (particle size at which the volume cumulative frequency from the smaller diameter side reaches 50%), and can be determined based on a particle size distribution obtained by a laser diffraction-scattering method, for example.

[0056] From the viewpoint of forming unevenness on the surface of the cured resin layer 50 (the outer surface 51 described below) to ensure the sliding property of the cured resin layer 50, the content of the particles in the cured resin layer 50 is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, further preferably 0.5 parts by mass or more, and further preferably 0.7 parts by mass or more, relative to 100 parts by mass of the curable resin. From the viewpoint of suppressing optical scattering on the surface of the cured resin layer 50, the content of the particles in the cured resin layer 50 is preferably 3.0 parts by mass or less, more preferably 2.0 parts by mass or less, further preferably 1.5 parts by mass or less, and further preferably 1.0 parts by mass or less, relative to 100 parts by mass of the curable resin. From the viewpoint of achieving both the above-mentioned securing of the sliding property of the cured resin layer 50 and suppressing optical scattering, the content of the particles in the cured resin layer 50 is preferably 0.1 to 3.0 parts by mass, more preferably 0.3 to 2.0 parts by mass, further preferably 0.5 to 1.5 parts by mass, and further preferably 0.7 to 1.0 parts by mass, relative to 100 parts by mass of the curable resin.

[0057] When the cured resin layer 50 contains nanoparticles, from the perspective of ensuring the hardness of the cured resin layer 50, the average particle size (D50) of the nanoparticles is preferably 20 nm or more, more preferably 25 nm or more, and further preferably 30 nm or more. From the perspective of uniform dispersion of the particles in the cured resin layer 50, the average particle size (D50) of the nanoparticles is preferably 300 nm or less, more preferably 200 nm or less, and further preferably 100 nm or less. From the perspective of ensuring both the hardness of the cured resin layer 50 and the uniform dispersion of the particles, the average particle size (D50) of the nanoparticles is preferably 20 to 300 nm, more preferably 25 to 200 nm, and further preferably 30 to 100 nm. The average particle size (D50) of the nanoparticles is the median particle size in the volume-based particle size distribution (the particle size at which the volume cumulative frequency from the small diameter side reaches 50%), and can be obtained, for example, based on the particle size distribution obtained by the laser diffraction-scattering method.

[0058] From the viewpoint of ensuring the hardness of the cured resin layer 50, the proportion of nanoparticles in the cured resin layer 50 is preferably 5% by mass or more, more preferably 8% by mass or more, and further preferably 10% by mass or more. From the viewpoint of uniform dispersion of particles in the cured resin layer 50, the proportion of nanoparticles in the cured resin layer 50 is preferably 30% by mass or less, more preferably 20% by mass or less, and further preferably 15% by mass or less. From the viewpoint of ensuring both the hardness of the cured resin layer 50 and the uniform dispersion of particles, the proportion of nanoparticles in the cured resin layer 50 is preferably 5 to 30% by mass, more preferably 8 to 20% by mass, and further preferably 10 to 15% by mass.

[0059] From the viewpoint of exhibiting sufficient scratch resistance in the cured resin layer 50, the thickness of the cured resin layer 50 is preferably 0.1 μm or more, more preferably 0.5 μm or more, further preferably 0.7 μm or more, and further preferably 0.9 μm or more. From the viewpoint of ensuring the adhesion of the cured resin layer 50 to the metal oxide layer 40, the thickness of the cured resin layer 50 is preferably 5 μm or less, more preferably 3 μm or less, further preferably 2 μm or less, and further preferably 1.5 μm or less. From the viewpoint of taking both the above-mentioned scratch resistance and the above-mentioned adhesion into consideration, the thickness of the cured resin layer 50 is preferably 0.1 to 5 μm, more preferably 0.5 to 3 μm, further preferably 0.7 to 2 μm, and further preferably 0.9 to 1.5 μm.

[0060] From the viewpoint of ensuring the light reflectivity of the reflective film X, the light reflectivity (Y value) of the reflective film X at a wavelength of 380 nm to 780 nm in the CIE-XYZ colorimetric system is preferably 80% or more, more preferably 82% or more, and further preferably 85% or more. The light reflectivity is, for example, 90% or less, 95% or less, or 100% or less. The light reflectivity (Y value) of the reflective film X is set as the reflectivity of light irradiated to the reflective film X from the substrate film 10 side.

[0061] The cured resin layer 50 has an outer surface 51 on the opposite side to the metal reflective layer 40. The water contact angle of the outer surface 51 is 80° or less, preferably 77° or less, more preferably 75° or less, and further preferably 73° or less. When the water contact angle is below the above upper limit, wettability can be ensured on the outer surface 51, and good adhesion (PSA adhesion) with respect to the adhesive can be ensured. The water contact angle of the outer surface 51 is preferably 50° or more, more preferably 60° or more, further preferably 65° or more, and further preferably 70° or more. When the water contact angle is above the above lower limit, the sliding property of the outer surface 51 of the cured resin layer 50 can be ensured. From the viewpoint of taking into account the above-mentioned PSA adhesion and sliding property of the outer surface 51, the water contact angle of the outer surface 51 is preferably 50° to 80°, more preferably 60° to 77°, further preferably 65° to 75°, and further preferably 70° to 73°. The method for measuring the water contact angle is described in the following examples.

[0062] As a method for adjusting the water contact angle, for example, there can be listed the selection of the type of leveling agent in the cured resin layer 50 and the adjustment of the amount thereof. As a method for adjusting the water contact angle, there can also be listed the selection of the type of particles in the cured resin layer 50, the adjustment of the average particle size, and the adjustment of the amount thereof.

[0063] The dynamic friction coefficient of the outer surface 51 relative to the polyethylene terephthalate (PET) film is 0.23 or less, preferably 0.22 or less, and more preferably 0.21 or less. When the dynamic friction coefficient is below the upper limit value, the sliding property of other components when in contact with the outer surface 51 can be ensured. The higher the sliding property of the outer surface 51, the less likely it is to be damaged. The dynamic friction coefficient of the outer surface 51 relative to the PET film is preferably 0.15 or more, more preferably 0.18 or more, and further preferably 0.20 or more. When the dynamic friction coefficient is above the lower limit value, the frequency of friction between the component and the outer surface 51 can be reduced when there are other components in contact with the outer surface 51 in a non-fixed state. The fewer the number of times other components rub against the outer surface 51, the less likely it is to be damaged. From the viewpoint of both ensuring the above-mentioned sliding property and suppressing the above-mentioned friction frequency, the dynamic friction coefficient of the outer surface 51 relative to the PET film is preferably 0.15 to 0.23, more preferably 0.18 to 0.22, and further preferably 0.20 to 0.21. The method for measuring the dynamic friction coefficient is described below in connection with the embodiments. As a method for adjusting the dynamic friction coefficient, for example, the selection of the type of leveling agent in the cured resin layer 50 and the adjustment of the amount thereof can be cited. As a method for adjusting the dynamic friction coefficient, the selection of the type of particles in the cured resin layer 50, the adjustment of the average particle size, and the adjustment of the amount thereof can also be cited.

[0064] The reflective film X is produced in a roll-to-roll method, for example, as follows.

[0065] First, if Figure 2A As shown, a metal reflective layer 20 is formed on the base film 10 (metal reflective layer forming step). Specifically, a metal film is formed on the first surface 11 of the base film 10 by dry coating to form the metal reflective layer 20. Examples of dry coating methods include sputtering and evaporation. The dry coating method is preferably sputtering.

[0066] In the sputtering method, for example, a sputtering film forming device that can perform a film forming process in a roll-to-roll manner is used. In the sputtering method, specifically, a sputtering gas (inert gas) is introduced into a film forming chamber of the sputtering film forming device under vacuum conditions, and a negative voltage is applied to a target arranged on a cathode in the film forming chamber. As a result, a glow discharge is generated, gas atoms are ionized, and the gas ions collide with the target surface at high speed, ejecting the target material from the target surface, and depositing the ejected target material on the substrate film 10.

[0067] The material of the target arranged on the cathode in the film forming chamber (i.e., the material of the metal reflective layer 20) is the metal mentioned above for the metal reflective layer 20. The gas pressure in the film forming chamber in the film forming by sputtering (sputtering film forming) is, for example, 0.02 Pa or more, and, for example, is less than 1 Pa. As a power source for applying voltage to the target, for example, there can be listed: a DC (Direct Current) power supply, an AC (Alternating Current) power supply, an MF (Middle Frequency) power supply, and an RF (Radio Frequency) power supply (the same also applies to the sputtering film forming described below for the blackening layer 30 and the metal oxide layer 40). The absolute value of the discharge voltage in the sputtering film forming is, for example, 50 V or more, and, for example, is less than 500 V (the same also applies to the sputtering film forming described below for the blackening layer 30 and the metal oxide layer 40).

[0068] Then, if Figure 2B As shown, a black layer 30 is formed on the metal reflective layer 20 (black layer forming step). Specifically, a material is formed into a film on the metal reflective layer 20 by a dry coating method to form the black layer 30. Examples of dry coating methods include sputtering and evaporation. The dry coating method is preferably sputtering.

[0069] The material of the target arranged on the cathode in the sputtering method (i.e., the material of the black layer 30) is, for example, a sintered body containing the above-mentioned metal compound and metal element for the black layer 30. The gas pressure in the film forming chamber during the sputtering film forming of the black layer 30 is, for example, not less than 0.02 Pa, and, for example, not more than 1 Pa.

[0070] If a dry coating method is used, the black layer 30 can be formed thinner than a conventional black ink layer formed by containing a resin component. In such a thin black layer 30, the difference between the compressive residual stress on the side fixed to the metal reflective layer 20 and the compressive residual stress on the opposite side to the metal reflective layer 20 is small (the thinner the black layer 30, the smaller the difference in the compressive residual stress on both sides). In addition, the small difference in the compressive residual stress on both sides in the thickness direction H of the black layer 30 helps to ensure the adhesion of the black layer 30 to the metal reflective layer 20.

[0071] Then, if Figure 2C As shown, a metal oxide layer 40 is formed on the blackened layer 30 (metal oxide layer forming step). Specifically, a material is formed into a film on the blackened layer 30 by dry coating to form the metal oxide layer 40. Examples of dry coating methods include sputtering and evaporation. The dry coating method is preferably sputtering.

[0072] The material of the target arranged on the cathode in the sputtering method (i.e., the material of the metal oxide layer 40) is, for example, a sintered body of the metal oxide described above with respect to the metal oxide layer 40. The gas pressure in the film forming chamber during the sputtering film forming of the metal oxide layer 40 is, for example, not less than 0.02 Pa, and, for example, not more than 1 Pa.

[0073] A series of processes from the metal reflective layer forming step to the metal oxide layer forming step are carried out on a single conveyor line while conveying the working film in a roll-to-roll manner. In the process on the single conveyor line, the working film is never exposed to the atmosphere. After the metal reflective layer 20 is formed, the blackening layer 30 and the metal oxide layer 40 are sequentially formed on the metal reflective layer 20 without exposing the working film to the atmosphere, which helps to ensure the adhesion of the blackening layer 30 and the metal oxide layer 40 to the metal reflective layer 20.

[0074] Then, if Figure 2D As shown, a cured resin layer 50 is formed on the metal oxide layer 40 (cured resin layer forming step). The cured resin layer 50 can be formed by applying the above-mentioned curable resin composition on the metal oxide layer 40 to form a coating film, and then curing the coating film. When the curable resin composition contains an ultraviolet curable resin, the coating film is cured by ultraviolet irradiation. When the curable resin composition contains a thermosetting resin, the coating film is cured by heating.

[0075] As described above, the reflective film X can be manufactured.

[0076] like Figure 3 As shown, the reflective film X may not include the black layer 30. Such a reflective film X may be formed by not performing the above-mentioned black layer forming step ( Figure 2B In order to ensure the light shielding property of the reflective film X, the reflective film X preferably includes a blackened layer 30 .

[0077] like Figure 4 As shown, the reflective film X may not include the metal oxide layer 40. Such a reflective film X may be formed by not performing the above-mentioned metal oxide layer forming step ( Figure 2C ). From the viewpoint of suppressing corrosion of the metal reflective layer 20 and the blackened layer 30 by the metal oxide layer 40, the reflective film X preferably includes the metal oxide layer 40.

[0078] As described above, the water contact angle of the outer surface 51 of the curing resin layer 50 of the reflective film X is 80° or less, preferably 77° or less, more preferably 75° or less, and further preferably 73° or less. Thus, wettability can be ensured on the outer surface 51, and good adhesion to the adhesive can be achieved. In addition, as described above, the dynamic friction coefficient of the outer surface 51 of the reflective film X relative to the PET film is 0.23 or less, preferably 0.22 or less, and more preferably 0.21 or less. Thus, the sliding property when other components come into contact with the outer surface 51 can be ensured, and the outer surface 51 is not easily damaged.

[0079] Therefore, the cured resin layer 50 as the outermost layer of the reflective film X can achieve both adhesion to the adhesive and resistance to scratching.

[0080] [Example]

[0081] The following examples are shown to specifically describe the present invention. However, the present invention is not limited to the examples. In addition, the specific numerical values ​​of the following amounts (contents), physical property values, parameters, etc. can be replaced by the upper limits (defined as "below" or "less than") or lower limits (defined as "above" or "exceeding") of the amounts (contents), physical property values, parameters, etc. corresponding to these numerical values ​​recorded in the above-mentioned "Specific Embodiments".

[0082] [Example 1]

[0083] First, a white polyethylene terephthalate (PET) film (product name "Lumirror E20", thickness 38 μm, manufactured by Toray) was prepared as a base film.

[0084] Next, a metal reflective layer, a blackened layer and a metal oxide layer are sequentially formed on one surface (first surface) of the PET film by sputtering (sputtering film forming process). In the sputtering film forming process, a roll-to-roll sputtering film forming device (DC magnetron sputtering film forming device) is used. The device includes a delivery chamber, a first film forming chamber, a second film forming chamber, a third film forming chamber and a winding chamber. The delivery chamber includes a delivery roller. A roll of the above-mentioned substrate film as a working film is provided on the delivery roller. The winding chamber includes a winding roller capable of winding the working film. In the first film forming chamber to the third film forming chamber, the working film is moved from the delivery chamber to the winding chamber by a roll-to-roll method, and the film forming process is implemented.

[0085] Specifically, in the sputtering film forming process, the first sputtering film forming in the first film forming chamber, the second sputtering film forming in the second film forming chamber, and the third sputtering film forming in the third film forming chamber are sequentially performed, and then the working film (substrate film / metal reflective layer / blackening layer / metal oxide layer) is wound on the winding roller of the winding chamber. In the first sputtering film forming, a metal reflective layer (Al) with a thickness of 75nm is formed on the first surface of the PET film. Then, in the second sputtering film forming, a blackening layer (In) with a thickness of 25nm is formed on the metal reflective layer. 2 O 3 +Cu). Then, in the third sputtering film formation, a metal oxide layer (ITO) with a thickness of 20 nm is formed on the blackened layer. The details of each sputtering film formation are as follows.

[0086] In the first sputtering film formation, after the sputtering film forming device (delivery chamber, first to third film forming chambers, winding chamber) is vacuum evacuated, argon (Ar) is introduced into the first film forming chamber as a sputtering gas, so that the gas pressure in the first film forming chamber is 0.3-0.4 Pa. As a target, an Al target (made by Mitsui Metals) is used. As a power source for applying voltage to the target, a DC power source is used. The film forming temperature (the temperature of the substrate film stacked with an Al layer) is set to 40°C. The type of sputtering gas, the gas pressure in the film forming chamber, the type of power source, and the film forming temperature are the same in the second sputtering film formation and the third sputtering film formation.

[0087] In the second sputtering film formation, a black inorganic target (product name "DIABLA12", indium oxide (In 2 O 3 ) and copper (Cu), In ratio is 67.3 (±3) mass %), manufactured by Mitsubishi Materials Co., Ltd.

[0088] In the third sputtering film formation, an ITO target (a composite oxide of indium oxide and tin oxide, tin oxide concentration of 10% by mass, manufactured by Mitsui Kinzoku) was used as a target.

[0089] Next, a curable resin composition is applied on the metal oxide layer to form a coating film. The curable resin composition contains: 100 parts by mass of a UV-curable acrylic urethane resin (product name "Aica AITRON Z844", manufactured by Aica Industries), 0.7 parts by mass of anti-blocking (AB) particles (product name "MBX-2H", polymethacrylate particles, average particle size (D50) 2.5 μm, manufactured by Sekisui Chemicals), 0.04 parts by mass of a silicone-based leveling agent (product name "Polyflow LE303", manufactured by Kyoeisha Chemicals), and methyl ethyl ketone as a solvent. Table 1 shows the composition of the curable resin composition. Next, after the coating film is dried, the coating film is cured by ultraviolet irradiation to form a cured resin layer with a thickness of 1 μm.

[0090] As described above, the reflective film of Example 1 was produced. The reflective film of Example 1 comprises a base film (white PET, thickness 38 μm), a metal reflective layer (Al, thickness 75 nm), a blackened layer (In 2 O 3 +Cu, thickness 25nm), metal oxide layer (ITO, thickness 20nm) and cured resin layer (thickness 1μm) are stacked. In Example 1, the metal reflective layer, black layer, metal oxide layer and cured resin layer on the substrate film form a multilayer film.

[0091] [Comparative Examples 1 to 3]

[0092] Reflective films of Comparative Examples 1 to 3 were prepared in the same manner as the reflective film of Example 1 except that the composition of the curable resin composition was changed as shown in Table 1. The leveling agent used in Comparative Example 1 was a fluorine-based leveling agent (product name "Polyflow LE604", manufactured by Kyoeisha Chemical Co., Ltd.).

[0093] 〈Thickness of each layer〉

[0094] The thickness of the metal reflective layer, the blackened layer, and the metal oxide layer of each reflective film of the embodiment and the comparative example was measured by observation using a field emission transmission electron microscope (FE-TEM). Specifically, first, a cross-sectional observation sample of each multilayer film of the embodiment and the comparative example was prepared by a FIB (Focused Ion beam) microsampling method. In the FIB microsampling method, a FIB device (product name "FB2200", manufactured by Hitachi) was used, and the acceleration voltage was set to 10 kV. Next, the cross section of the multilayer film of the cross-sectional observation sample was observed by FE-TEM, and the thickness of the metal reflective layer, the blackened layer, and the metal oxide layer was measured in the observed image. In the observation, a FE-TEM device (product name "JEM-2800", manufactured by JEOL) was used, and the acceleration voltage was set to 200 kV. The thickness of each layer is as described above.

[0095] 〈Light reflectivity〉

[0096] The light reflectance of each reflective film of the example and the comparative example was measured as follows.

[0097] First, the side of the reflective film opposite to the substrate film side (the outer surface of the cured resin layer) is bonded to a black acrylic plate with the aid of a specified adhesive. Thus, a laminated film is obtained. Next, a film piece (film piece) for measurement is cut out from the laminated film. Next, the light reflectance of the film piece is measured by a spectrophotometer (product name "U-4100", manufactured by Hitachi High-Tech Corporation). The reflectance is the light reflectance (Y value) of the irradiation light of the wavelength of 380nm to 780nm of the film piece in the CIE-XYZ colorimetric system. In this measurement, the film piece is placed in the spectrophotometer in such a way that light irradiates the film piece from the substrate film side of the film piece. The measurement results are shown in Table 2.

[0098] 〈Water contact angle〉

[0099] The water contact angle (pure water contact angle) of the outer surface of the cured resin layer in each reflective film of the embodiment and the comparative example was investigated. Specifically, first, water droplets were formed on the outer surface of the cured resin layer of the reflective film by dripping 3.5 μL of distilled water. Next, the angle between the surface of the water droplets on the cured resin layer and the surface (outer surface) of the cured resin layer was measured. In the measurement, a contact angle measuring device (product name "FACE CA-X type", manufactured by Kyowa Interface Chemical Co., Ltd.) was used. Regarding the measurement conditions, the temperature was set to 23°C and the relative humidity was set to 50%. The measurement results are shown in Table 2.

[0100] 〈Dynamic friction coefficient〉

[0101] For each of the reflective films of Examples and Comparative Examples, the dynamic friction coefficient of the surface of the cured resin layer was measured as follows.

[0102] First, a sample film (10 cm × 10 cm) was cut out from the reflective film. Next, the sample film was horizontally placed on the workbench of an automatic friction and wear analysis device (product name "TSf-503", the measurement method was a surface contact type of the Bowden method, manufactured by Kyowa Interface Science Co., Ltd.) with its cured resin layer surface as the upper surface. A white polyethylene terephthalate (PET) film (product name "Lumirror E20", thickness 38 μm, manufactured by Toray) having the same size as the lower end surface was fixed to the lower end surface (10 mm × 10 mm) of the contact equipped in the device, and a contact with a PET film was prepared. Then, a sliding test was performed in which the contact with a PET film was made to slide relative to the surface of the cured resin layer. In the sliding test, the contact with a PET film was reciprocated in one direction while the PET film surface of the contact with a PET film was pressed against the surface of the cured resin layer with a load of 200 g. The sliding length was set to 30 mm. Through such a sliding test, the dynamic friction coefficient of the surface of the cured resin layer relative to the PET film was measured. Table 2 shows the measurement results.

[0103] 〈Adhesion〉

[0104] For each of the reflective films of Examples and Comparative Examples, the adhesion of the cured resin layer to the adhesive was examined as follows.

[0105] First, a sample film (length 100 mm × width 25 mm) is cut out from the reflective film. Next, the cured resin layer side of the sample film is joined to a glass plate with the aid of a double-sided tape (product name "No.5000", manufactured by Nitto Denko). Next, a 180° peeling test is performed to peel the sample film from the double-sided tape on the glass plate along its length direction, and the force required for peeling (peeling force) is measured. A tensile testing machine (product name "TCM-1kNB", manufactured by NMB Minebea) is used in this measurement. In this measurement, the measurement temperature is set to 23°C, the relative humidity is set to 50%, the peeling angle for peeling the sample film from the glass plate is set to 180°, and the tensile speed is set to 300 mm / min. The measured peeling force is shown in Table 2 as the adhesive (PSA) adhesion (N / 25 mm).

[0106] 〈Injury Evaluation〉

[0107] The reflective films of Examples and Comparative Examples were examined for their resistance to damage to the cured resin layer as follows.

[0108] First, slide the tip of a rechargeable touch pen for a touch panel (product name "MS-TP22WH", manufactured by MS Solutions) on the outer surface (exposed surface) of the cured resin layer of the reflective film. In this sliding, the sliding load is set to 50 g, the sliding distance is set to 100 mm, the sliding speed is set to 150 mm / second, and the number of sliding times is set to 1. Next, irradiate the sliding portion on the cured resin layer side of the reflective film with light. As a light source for light irradiation, an LED light source (product name "MG-845R", manufactured by GENTOS) is used. Next, by visually observing from the substrate film side of the anti-reflective film, confirm whether the irradiated light passes through the reflective film. Then, the case where the irradiated light is not confirmed to pass through is evaluated as "no scratches", and the case where the irradiated light is confirmed to pass through is evaluated as "scratches". The evaluation results are shown in Table 2.

[0109] [Table 1]

[0110]

[0111] [Table 2]

[0112]

[0113] It should be noted that the above invention is provided as an exemplary embodiment of the present invention, but this is merely an example and is not to be construed as limiting. Modifications of the present invention that are obvious to those skilled in the art are included in the claims.

[0114] Industrial Applicability

[0115] The reflective film of the present invention can be used as a reflective film disposed in a frame portion of a housing of a liquid crystal display device, for example.

Claims

1. A reflective film comprising a substrate film, a metal reflective layer and a cured resin layer in this order in a thickness direction, The water contact angle of the outer surface of the cured resin layer on the side opposite to the metal reflective layer is 80° or less, The coefficient of dynamic friction of the outer surface with respect to the polyethylene terephthalate film is 0.23 or less.

2. The reflective film according to claim 1, wherein The water contact angle is 50° or more.

3. The reflective film according to claim 1, wherein The dynamic friction coefficient is greater than 0.

15.

4. The reflective film according to claim 1, wherein: The metal reflective layer is an aluminum layer.

5. The reflective film according to any one of claims 1 to 4, wherein A metal oxide layer is further provided between the metal reflective layer and the cured resin layer.

6. The reflective film according to claim 5, wherein: The metal oxide layer is an indium tin oxide layer.

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