Laminate, method for producing laminate, and antireflection film

Abstract

A laminate (1) includes a substrate (2), a protective layer (3), and a titanium oxide film (4) in this order toward one side in the thickness direction. The titanium oxide film (4) includes crystals that show a group of Ti2O3 diffraction spots in an electron beam diffraction image observed with a transmission electron microscope, wherein a refractive index when light with a wavelength of 550 nm is incident thereon exceeds 2.50 but 2.80 or less.

Description

Laminate, method for manufacturing the same, and anti-reflective film

[0001] This invention relates to a laminate, a method for manufacturing the same, and an anti-reflective film.

[0002] In image display devices such as liquid crystal displays and organic EL displays, an anti-reflective film is placed on the outermost surface of the display screen to prevent reflection of ambient light. Such an anti-reflective film comprises a transparent substrate film and an anti-reflective layer including a high refractive index layer and a low refractive index layer.

[0003] As a high refractive index layer used in such anti-reflective films, rutile-type titanium oxide (TiO2) is deposited at room temperature by high-power magnetron impulse sputtering (HiPIMS). ２ A membrane has been proposed (see, for example, Non-Patent Document 1).

[0004] Aiempanakit et al. Surface & Coatings Technology, 205 (2011) 4828-4831.

[0005] However, the rutile-type TiO mentioned above ２ When a film is deposited on a polymer film using HiPIMS, the surface of the polymer film is damaged, making it impossible to deposit the titanium oxide film.

[0006] On the other hand, by depositing titanium oxide using magnetron sputtering (DCMS) with a DC power supply, rutile-type TiO2 is deposited on a polymer film using a roll-to-roll method. ２ Although a film is formed, the deposition rate remains at around 0.005 nm / sec, resulting in a decrease in the manufacturing efficiency of titanium oxide films. Therefore, there is a need for a titanium oxide film that can be deposited on the surface of a substrate, such as a polymer film, without damaging it, and that also offers excellent manufacturing efficiency.

[0007] Furthermore, when a titanium oxide film is used as a high refractive index layer in an anti-reflective film, a high refractive index is required to reduce the reflectivity of ambient light. On the other hand, if the refractive index is too high, wavelength dispersion of ambient light occurs, and the reflectivity of the anti-reflective film does not decrease over a wide wavelength range.

[0008] The present invention aims to provide a laminate having a titanium oxide film with no damage on the surface of a substrate, excellent in production efficiency and antireflection performance, a method for producing the same, and an antireflection film.

[0009] The present invention [1] includes a substrate, a protective layer, and a titanium oxide film provided in this order on one side in the thickness direction, and in the electron diffraction image observed by a transmission electron microscope, the titanium oxide film contains a crystal in which a diffraction spot group of Ti ２ O ３ appears, and the refractive index when light with a wavelength of 550 nm is incident is more than 2.50 and 2.80 or less, and includes a laminate.

[0010] The present invention [2] includes the laminate according to [1], in which the refractive index is more than 2.68.

[0011] The present invention [3] is a method for producing the laminate according to [1], and includes a first step of preparing the substrate, a second step of forming the protective layer on one side in the thickness direction of the substrate, and a third step of forming a titanium oxide film using high-power impulse magnetron sputtering (HiPIMS) on one side in the thickness direction of the protective layer with a film formation temperature of 70°C or higher, and includes a method for producing a laminate.

[0012] The present invention [4] includes the method for producing the laminate according to [3], in which the third step is carried out with a film formation temperature of 100°C or higher.

[0013] The present invention [5] includes the method for producing the laminate according to [3] or [4], in which the second step and the third step are carried out in a roll-to-roll manner.

[0014] The present invention [6] includes an antireflection film including the laminate according to [1] or [2], and a low refractive index layer having a refractive index smaller than that of the titanium oxide film, provided in this order on one side in the thickness direction, and the titanium oxide film is a high refractive index layer.

[0015] The present invention [7] includes the antireflection film according to [6], including two or more alternating laminates composed of the high refractive index layer and the low refractive index layer.

[0016] The laminate of the present invention includes a base material, a protective layer, and a titanium oxide film in this order toward one side in the thickness direction. In the electron diffraction image observed with a transmission electron microscope, the titanium oxide film contains crystals in which diffraction spot groups of Ti ２ O ３ appear. When light with a wavelength of 550 nm is incident, the refractive index is more than 2.50 and 2.80 or less. Therefore, the laminate of the present invention has no damage on the surface of the base material, and when the laminate is used as an antireflection film, the antireflection film has excellent antireflection performance. Further, since the amount of oxygen in the crystals contained in the titanium oxide film is less than the amount of oxygen contained in TiO ２ , the film formation rate of the titanium oxide film is high, and the production efficiency of the titanium oxide film is excellent.

[0017] The method for producing a laminate of the present invention includes a first step of preparing a base material, a second step of forming a protective layer on one side in the thickness direction of the base material, and a third step of forming a titanium oxide film using high-power impulse magnetron sputtering (HiPIMS) on one side in the thickness direction of the protective layer with the film formation temperature being 70°C or higher. The laminate produced according to the present invention contains crystals in which diffraction spot groups of Ti ２ O ３ appear in the electron diffraction image observed with a transmission electron microscope. When light with a wavelength of 550 nm is incident, the refractive index is more than 2.50 and 2.80 or less. Therefore, the laminate has no damage on the surface of the base material, and when the laminate is used as an antireflection film, the antireflection film has excellent antireflection performance. Further, since the amount of oxygen in the crystals contained in the titanium oxide film is less than the amount of oxygen contained in TiO ２ , the film formation rate of the titanium oxide film is high, and the production efficiency of the titanium oxide film is excellent.

[0018] The antireflection film of the present invention includes the laminate of the present invention and a low refractive index layer having a refractive index smaller than that of the titanium oxide film in this order toward one side in the thickness direction. The titanium oxide film is a high refractive index layer. Therefore, the laminate contained in the antireflection film has no damage on the surface of the base material, and the antireflection film has excellent antireflection performance.

[0019] Figure 1 shows one embodiment of the laminate of the present invention. Figures 2A to 2C show one embodiment of the method for manufacturing the laminate of the present invention. Figure 2A shows the first step of preparing a substrate, Figure 2B shows the second step of forming a protective layer on one side of the substrate in the thickness direction, and Figure 2C shows the third step of forming a titanium oxide film on one side of the protective layer in the thickness direction. Figure 3 shows one embodiment of the anti-reflective film of the present invention. Figure 4 shows another embodiment of the anti-reflective film of the present invention.

[0020] 1. Laminate One embodiment of the laminate of the present invention will be described with reference to Figure 1.

[0021] As shown in Figure 1, the laminate 1 has a film shape (including a sheet shape) with a predetermined thickness. The laminate 1 extends in a plane direction perpendicular to the thickness direction, and one surface in the thickness direction and the other surface in the thickness direction of the laminate 1 are flat.

[0022] The laminate 1 comprises a base material 2, a protective layer 3, and a titanium oxide film 4, arranged in order toward one side in the thickness direction. Specifically, as shown in Figure 1, the laminate 1 comprises a base material 2, a protective layer 3 disposed on one side of the base material 2 in the thickness direction, and a titanium oxide film 4 disposed on one side of the protective layer 3 in the thickness direction.

[0023] <Substrate> Substrate 2 is the bottom layer of the laminate 1. Substrate 2 comprises a transparent resin film 21 and a cured resin layer 22 in order toward one side in the thickness direction. Specifically, substrate 2 comprises a transparent resin film 21 and a cured resin layer 22 disposed on one side of the transparent resin film 21 in the thickness direction. More specifically, substrate 2 comprises, for example, a transparent resin film 21 and a cured resin layer 22 disposed on one side of the transparent resin film 21 in the thickness direction.

[0024] The base material 2 preferably consists of a transparent resin film 21 and a cured resin layer 22 disposed on one side in the thickness direction of the transparent resin film 21. Specifically, the base material 2 preferably consists of a transparent resin film 21 and a cured resin layer 22 disposed on one side in the thickness direction of the transparent resin film 21.

[0025] The total light transmittance (JIS K-7105) when light with a wavelength of 550 nm is incident on the substrate 2 is, for example, 80% or more, preferably 85% or more, more preferably 88% or more, even more preferably 90% or more, and also, for example, 100% or less.

[0026] The thickness of the base material 2 is not particularly limited, but from the viewpoint of strength and handling, it is, for example, 10 μm or more, preferably 30 μm or more, more preferably 50 μm or more, and also, for example, 200 μm or less, preferably 150 μm or less, more preferably 100 μm or less.

[0027] The transparent resin film 21 is a transparent, flexible resin film. Examples of materials for the transparent resin film 21 include cellulose resin, polyester resin, (meth)acrylic resin (acrylic resin and / or methacrylic resin), olefin resin, polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, polystyrene resin, norbornene resin, and polyvinyl alcohol resin. Examples of polyester resins include polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate. Examples of polyolefin resins include polyethylene, polypropylene, and cycloolefin polymer (COP). Examples of cellulose resins include triacetylcellulose (TAC). The materials for the transparent resin film 21 can be used individually or in combination of two or more.

[0028] The transparent resin film 21 can be, for example, a cellulose resin film, from the viewpoint of transparency, heat resistance, and mechanical strength. Preferably, a triacetylcellulose (TAC) film is used.

[0029] The total light transmittance (JIS K-7105) when light with a wavelength of 550 nm is incident on the transparent resin film 21 is, for example, 80% or more, preferably 85% or more, more preferably 88% or more, even more preferably 90% or more, and also, for example, 100% or less.

[0030] The thickness of the transparent resin film 21 is not particularly limited, but from the viewpoint of strength and handling, for example, it is 5 μm or more, preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, and particularly preferably 50 μm or more. Alternatively, for example, it is 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, even more preferably 170 μm or less, and particularly preferably 150 μm or less.

[0031] The thickness of the transparent resin film 21 can be measured, for example, using a film thickness gauge.

[0032] The cured resin layer 22 is a layer that improves the mechanical properties of the laminate 1. The cured resin layer 22 is positioned on one side in the thickness direction of the transparent resin film 21 and on the other side in the thickness direction of the protective layer 3. Specifically, as shown in Figure 1, the cured resin layer 22 is positioned on one side in the thickness direction of the transparent resin film 21. In other words, the cured resin layer 22 is in contact with the transparent resin film 21.

[0033] Examples of the cured resin layer 22 include a hard coat layer and an anti-blocking layer. The hard coat layer, for example, makes it difficult for scratches to form on the exposed surface of the transparent resin film 21. The anti-blocking layer provides anti-blocking properties to the surfaces of multiple laminates 1 that come into contact with each other, for example, when the laminates 1 are stacked in the thickness direction.

[0034] The cured resin layer 22 is, for example, a cured product of a curable resin composition. Specifically, the cured resin layer 22 can be formed by applying a curable resin composition to one side in the thickness direction of the transparent resin film 21, and then curing it after drying as necessary.

[0035] 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. Acrylic urethane resins are preferred. The curable resins can be used alone or in combination of two or more types.

[0036] Furthermore, examples of curable resin compositions include ultraviolet-curable resin compositions and thermosetting resin compositions. From the viewpoint of manufacturing efficiency, ultraviolet-curable resin compositions are preferably used as curable resin compositions. A specific example of an ultraviolet-curable resin composition is the hard coat layer forming composition described in Japanese Patent Application Publication No. 2016-179686.

[0037] The curable resin composition may contain fine particles in the curable resin layer 22 from the viewpoint of adjusting hardness, surface roughness, refractive index, and providing anti-glare properties. Examples of fine particles include inorganic particles and organic particles. Inorganic particles are preferred. Examples of inorganic particles include inorganic oxide particles. Examples of materials for inorganic oxide particles include silica, alumina, titania, zirconia, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. Silica is preferred. Examples of materials for organic particles include polymethyl methacrylate, polystyrene, polyurethane, acrylic-styrene copolymer, benzoguanamine, melamine, and polycarbonate.

[0038] The thickness of the cured resin layer 22 is, for example, 1 μm or more, preferably 2 μm or more, more preferably 5 μm or more, and also, for example, 15 μm or less, preferably 12 μm or less, more preferably 10 μm or less.

[0039] If the thickness of the cured resin layer 22 is greater than or equal to the lower limit mentioned above, the cured resin layer 22 can be easily formed and its functions can be fully expressed. Also, if the thickness of the cured resin layer 22 is less than or equal to the upper limit mentioned above, the laminate 1 can be made thinner.

[0040] One side of the cured resin layer 22 in the thickness direction may be surface-modified to improve adhesion with the protective layer 3. Examples of surface modification treatments include corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, saponification treatment, and treatment with a coupling agent. Plasma treatment is preferred.

[0041] <Protective Layer> The protective layer 3 is a layer that prevents damage to the surface of the cured resin layer 22 when the titanium oxide film 4 is formed by HiPIMS, as described later, and improves the adhesion of the titanium oxide film 4 to the substrate 2.

[0042] The protective layer 3 is positioned on one side in the thickness direction of the cured resin layer 22 and on the other side in the thickness direction of the titanium oxide film 4. Specifically, as shown in Figure 1, the protective layer 3 is positioned on one side in the thickness direction of the cured resin layer 22. In other words, the protective layer 3 is in contact with the cured resin layer 22.

[0043] The protective layer 3 has a film shape (including a sheet shape) with a predetermined thickness. The protective layer 3 extends in a plane direction perpendicular to the thickness direction, and one surface of the protective layer 3 in the thickness direction and the other surface in the thickness direction are flat.

[0044] The protective layer 3 is a dry coating layer or a wet coating layer, preferably a dry coating layer, and more preferably a sputtered layer.

[0045] As for the material of the protective layer 3, in the case of a dry coating layer, an inorganic material can be used, and in the case of a wet coating layer, a mixture of an organic material and inorganic fine particles can be used.

[0046] Examples of inorganic materials include metals, alloys containing two or more metals, metalloids, and oxides thereof.

[0047] Examples of metals include nickel, chromium, indium, aluminum, tin, gold, silver, platinum, zinc, titanium, tungsten, zirconium, and palladium. Examples of metalloids include silicon. Examples of oxides include silicon-containing oxides, zinc-containing oxides, indium-containing oxides, and antimony-containing oxides. Examples of silicon-containing oxides include silicon oxide (SiO₂). ｘ Examples include (0 < x ≤ 2). Examples of zinc-containing oxides include aluminum zinc silicon composite oxide (Al-Zn-SiO ｘExamples of indium-containing oxides include indium-tin composite oxide (ITO), indium-zinc composite oxide (IZO), indium-gallium composite oxide (IGO), and indium-gallium-zinc composite oxide (IGZO). An example of an antimony-containing oxide is antimony-tin composite oxide (ATO). The material of the protective layer 3 is preferably silicon and silicon oxide (SiO ｘ ) (0 < x ≤ 2). That is, the protective layer 3 is preferably a silicon layer and a silicon oxide layer.

[0048] If the protective layer 3 is a silicon layer or a silicon oxide layer, the titanium oxide film 4 is formed without damaging the surface of the cured resin layer 22 by HiPIMS, as described later, and the adhesion of the titanium oxide film 4 to the substrate 2 is improved.

[0049] Examples of mixtures of organic materials and inorganic fine particles include a binder resin and inorganic fine particles dispersed in the binder resin.

[0050] Examples of binder resins include cured products of UV-curable resins. Examples of UV-curable resins include epoxy resins, acrylic urethane resins, acrylic resins (excluding acrylic urethane resins), and urethane resins (excluding acrylic urethane resins).

[0051] Examples of inorganic nanoparticles include metal oxide nanoparticles. Examples of metal oxides include zirconium oxide, aluminum oxide, titanium oxide, and silicon oxide.

[0052] The hardness (surface hardness H) of the surface of the protective layer 3 at 25°C, measured by nanoindentation, is, for example, 1.05 GPa or higher, preferably 1.1 GPa or higher, more preferably 1.15 GPa or higher, and also, for example, 30 GPa or lower, preferably 20 GPa or lower, more preferably 15 GPa or lower. If the surface hardness H is within the above upper and lower limits, the titanium oxide film 4 is formed without damaging the surface of the cured resin layer 22 by HiPIMS described later, and the adhesion of the titanium oxide film 4 to the substrate 2 is improved.

[0053] The nanoindentation method is carried out in accordance with ISO 14577. The nanoindentation method employs the same method as in Examples 1 to 4 of Japanese Patent Publication No. 2023-013412.

[0054] The thickness of the protective layer 3 is, for example, 20 nm or more, preferably 30 nm or more, more preferably 40 nm or more, even more preferably 50 nm or more, and also, for example, 100 nm or less, preferably 90 nm or less, more preferably 80 nm or less, and even more preferably 70 nm or less.

[0055] If the thickness of the protective layer 3 is greater than or equal to the lower limit described above, the titanium oxide film 4 is formed on the surface of the cured resin layer 22 by HiPIMS described later, without damaging the surface, and the adhesion of the titanium oxide film 4 to the substrate 2 is improved. Also, if the thickness of the protective layer 3 is less than or equal to the upper limit described above, the laminate 1 becomes thinner.

[0056] <Titanium Oxide Film> As shown in Figure 1, the titanium oxide film 4 is, for example, one of the lamination elements of the laminate 1. The titanium oxide film 4 is the uppermost layer of the laminate 1. Specifically, the titanium oxide film 4 is positioned on one side in the thickness direction of the protective layer 3. In other words, the titanium oxide film 4 is in contact with the protective layer 3.

[0057] The titanium oxide film 4 has a film shape (including a sheet shape) with a predetermined thickness. The titanium oxide film 4 extends in a plane direction perpendicular to the thickness direction, and one surface in the thickness direction and the other surface in the thickness direction of the titanium oxide film 4 are flat.

[0058] The titanium oxide film 4 is a crystalline layer. The titanium oxide film 4 may also contain amorphous regions. Preferably, the titanium oxide film 4 is a layer that does not contain amorphous regions and contains only crystalline regions. The amorphous regions can be identified, for example, by observing the plane direction of the titanium oxide film 4 with a transmission electron microscope.

[0059] The titanium oxide film 4 contains titanium (Ti) oxide. Specifically, the titanium oxide film 4 shows Ti in the electron diffraction pattern observed with a transmission electron microscope. ２ O ３ The titanium oxide film 4 contains a crystal in which diffraction spots appear.２ O ３ In addition to crystals in which diffraction spots appear, Ti ２ O ３ The crystal may also contain other groups of diffraction spots. Specifically, the titanium oxide film 4 may contain rutile-type TiO ２ , anatase-type TiO ２ brookite-type TiO ２ The film may also contain crystals in which TiO diffraction spots appear. Preferably, in the titanium oxide film 4, the electron diffraction pattern observed with a transmission electron microscope shows Ti ２ O ３ Only the diffraction spots of Ti appear. ２ O ３ No other diffraction spot groups appear. The crystalline structure contained in the titanium oxide film 4 will be identified in detail by the analysis of the electron diffraction pattern, as described later.

[0060] In the electron diffraction pattern observed by a transmission electron microscope, the titanium oxide film 4 showed Ti ２ O ３ If the titanium oxide film 4 contains crystals in which diffraction spots appear, the amount of oxygen in the crystals is TiO ２ Because the amount of oxygen contained is less than that of the titanium oxide film 4, the film formation rate of the titanium oxide film 4 is high, resulting in excellent manufacturing efficiency.

[0061] In the titanium oxide film 4, Ti ２ O ３ The grain size of the crystal is, for example, 5 nm or more, preferably 6 nm or more, more preferably 8 nm or more, even more preferably 10 nm or more, and also, for example, 30 nm or less, preferably 28 nm or less, more preferably 26 nm or less, even more preferably 25 nm or less. In the titanium oxide film 4, Ti ２ O ３ The grain size can be determined, for example, by observing the crystal grains in the planar direction of the titanium oxide film 4 using a transmission electron microscope.

[0062] In the titanium oxide film 4, Ti ２ O ３If the crystal grain size is within the upper and lower limits described above, the refractive index of the titanium oxide film 4 when light with a wavelength of 550 nm is incident on it will be greater than 2.50 and less than or equal to 2.80. In other words, when the titanium oxide film 4 is used as a high refractive index layer in an anti-reflective film, the reflection of ambient light is suppressed, and the anti-reflective film exhibits excellent anti-reflective performance.

[0063] The refractive index of the titanium oxide film 4 when light with a wavelength of 550 nm is incident on it is greater than 2.50, preferably greater than 2.60, more preferably greater than 2.68, even more preferably greater than 2.70, and also 2.80 or less, preferably 2.78 or less, more preferably 2.77 or less, and even more preferably 2.75 or less. The refractive index of the titanium oxide film 4 when light with a wavelength of 550 nm is incident on it is determined by refractive index measurement as described later.

[0064] If the refractive index of the titanium oxide film 4 when light with a wavelength of 550 nm is incident on it is within the upper and lower limits described above, then when the laminate 1 containing the titanium oxide film 4 is used as an anti-reflective film, the reflection of ambient light is suppressed, and the anti-reflective film exhibits excellent anti-reflective performance.

[0065] The thickness of the titanium oxide film 4 is not particularly limited, but for example, it is 10 nm or more, preferably 20 nm or more, more preferably 30 nm or more, and even more preferably 40 nm or more. Alternatively, for example, it may be 250 nm or less, preferably 200 nm or less, more preferably 150 nm or less, and even more preferably 100 nm or less. The thickness of the titanium oxide film 4 can be determined, for example, by measuring the cross-section of the titanium oxide film 4 in the thickness direction using an FE-TEM (product name: JEM-2800, manufactured by JEOL).

[0066] If the thickness of the titanium oxide film 4 is less than or equal to the upper limit mentioned above, the refractive index of the titanium oxide film 4 can be increased, and when the laminate 1 containing the titanium oxide film 4 is used as an anti-reflective film, the reflection of ambient light is suppressed, and the anti-reflective film has excellent anti-reflective performance. Furthermore, if the thickness of the titanium oxide film 4 is greater than or equal to the lower limit mentioned above, the Ti in the electron diffraction pattern observed with a transmission electron microscope ２ O ３Crystals exhibiting these diffraction spots are easier to grow, and the refractive index of the titanium oxide film 4 can be increased.

[0067] The surface roughness Ra (arithmetic mean surface roughness) of one side in the thickness direction of the titanium oxide film 4 is, for example, 0.5 nm or more, preferably 0.8 nm or more, and also, for example, 10 nm or less, preferably 8 nm or less.

[0068] When light with a wavelength of 550 nm is incident on the titanium oxide film 4, the total light transmittance is, for example, 75% or more, preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more. There is no upper limit to the total light transmittance of the titanium oxide film 4. For example, the upper limit to the total light transmittance of the titanium oxide film 4 is 100%.

[0069] The thickness of the laminate 1 is, for example, 20 μm or more, preferably 30 μm or more, more preferably 50 μm or more, even more preferably 60 μm or more, and also, for example, 200 μm or less, preferably 180 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less.

[0070] When light with a wavelength of 550 nm is incident on the laminate 1, the total light transmittance is, for example, 80% or more, preferably 85% or more, more preferably 88% or more, even more preferably 90% or more, and also, for example, 100% or less.

[0071] <Applications> The laminate described above can be applied to anti-reflective films used in, for example, electronic equipment casings, vehicle-mounted accessories, home appliance casings, structural components, machine parts, various automotive parts, electronic equipment components, furniture, kitchenware, and the like.

[0072] 2. Manufacturing Method of Laminate A method of manufacturing a laminate will be described with reference to Figures 2A to 2C.

[0073] A method for manufacturing the laminate 1 includes, for example, a first step of preparing a substrate 2 (Figure 2A), a second step of forming a protective layer 3 on one side of the substrate 2 in the thickness direction (Figure 2B), and a third step of forming a titanium oxide film 4 on one side of the protective layer 3 in the thickness direction (Figure 2C).

[0074] <First Step> In the first step, the base material 2 is prepared as shown in Figure 2A.

[0075] To prepare the base material 2, a transparent resin film 21 is prepared, and a cured resin layer 22 is formed on one side of the transparent resin film 21 in the thickness direction.

[0076] To form the cured resin layer 22, the above-mentioned curable resin composition is applied to one side in the thickness direction of the transparent resin film 21 to form a coating film, and then this coating film is cured.

[0077] The curable resin composition may further contain a photopolymerization initiator, a leveling agent, and a solvent (diluent).

[0078] If the curable resin composition contains a solvent, the coating on the transparent resin film 21 is dried after the curable resin composition is applied.

[0079] The drying temperature is, for example, 50°C to 120°C. The drying time is, for example, 10 seconds to 10 minutes.

[0080] When the curable resin composition includes an ultraviolet-curable resin, the coating on the transparent resin film 21 is cured by ultraviolet irradiation. Examples of ultraviolet irradiation light sources include high-pressure mercury lamps and LED lights. Preferably, high-pressure mercury lamps are used. The cumulative amount of ultraviolet irradiation is, for example, 100 mJ / cm². ２ ~500 mJ / cm ２ That is the case.

[0081] <Second Step> In the second step, as shown in Figure 2B, a protective layer 3 is formed on one side of the substrate 2 in the thickness direction.

[0082] Methods for forming the protective layer 3 include dry coating and wet coating. Examples of dry coating methods include vacuum deposition, sputtering, and ion plating. Sputtering is preferred. Examples of wet coating methods include gravure coating, reverse coating, and die coating.

[0083] Examples of sputtering methods include two-electrode sputtering, ECR (electron cyclotron resonance) sputtering, magnetron sputtering, and ion beam sputtering. Preferably, reactive sputtering using the magnetron sputtering method is used.

[0084] In the second step, a sputtering deposition apparatus capable of performing the film deposition process using a roll-to-roll method is used. When a roll-to-roll sputtering deposition apparatus is used in the second step, the work film W (substrate 2) travels from the feed roll to the winding roll of the sputtering deposition apparatus, and the material for the protective layer 3 is deposited on one side in the thickness direction of the cured resin layer 22, thereby forming the protective layer 3. The travel speed of the work film W (substrate 2) is, for example, 0.1 to 10.0 m / min.

[0085] In the sputtering method, specifically, a sputtering gas is introduced into the deposition chamber under vacuum conditions, and a negative voltage is applied to a target made of the protective layer 3 material described above within the deposition chamber. This generates a glow discharge, ionizing the gas atoms, which then collide with the target surface at high speed, ejecting the target material from the target surface. The ejected target material is then deposited on one side of the work film W (substrate 2) in the thickness direction. The target is made of the protective layer 3 material described above, preferably silicon.

[0086] Examples of sputtering gases include inert gases and reactive gases. Examples of inert gases include argon, krypton, xenon, and mixtures thereof, with argon being preferred. Examples of reactive gases include oxygen. In reactive sputtering, for example, oxygen is introduced into the deposition chamber in addition to the inert gas. In other words, the protective layer 3 is deposited in the presence of an inert gas and / or oxygen.

[0087] The achievable vacuum level inside the deposition chamber is, for example, 1.0 × 10⁻⁶. －４ It is less than or equal to Pa.

[0088] When introducing an inert gas and oxygen into the film deposition chamber, the volume ratio of oxygen to the total volume of the inert gas and oxygen is, for example, 0.1% to 50% by volume, preferably 1% to 40% by volume, more preferably 5% to 30% by volume, and even more preferably 10% to 25% by volume.

[0089] The atmospheric pressure inside the deposition chamber (the atmospheric pressure inside the deposition chamber when an inert gas and / or oxygen is introduced) is, for example, 0.01 Pa to 5.0 Pa, preferably 0.05 Pa to 3.0 Pa, more preferably 0.10 Pa to 1.0 Pa, and even more preferably 0.15 Pa to 0.80 Pa.

[0090] The film deposition temperature (the temperature of the roll supporting the substrate 2) is, for example, room temperature.

[0091] Examples of power supplies for applying voltage to the target include DC power supplies, AC power supplies, MF power supplies, and RF power supplies. An MFAC power supply, which combines an MF power supply and an AC power supply, may also be used. Preferably, an MFAC power supply is used.

[0092] The discharge power is, for example, 0.1 kW to 10 kW, preferably 1 kW to 5 kW.

[0093] In the wet coating method, a coating liquid (varnish) containing the material for the protective layer 3 is applied to one side in the thickness direction of the cured resin layer 22 to form a coating film, and then the protective layer 3 is formed by drying and curing this coating film. Examples of materials for the protective layer 3 include a mixture of organic materials and inorganic fine particles, and more specifically, a binder resin and inorganic fine particles dispersed in the binder resin.

[0094] The drying temperature is, for example, 60°C to 120°C. The drying time is, for example, 10 minutes to 60 minutes.

[0095] The dried coating hardens upon exposure to ultraviolet (UV) light. Examples of UV light sources include high-pressure mercury lamps and LED lights. High-pressure mercury lamps are preferred. The cumulative UV irradiation intensity is, for example, 100 mJ / cm². ２ ~500 mJ / cm ２ That is the case.

[0096] By forming a protective layer 3 on one side in the thickness direction of the cured resin layer 22, the titanium oxide film 4 can be formed without damaging the surface of the cured resin layer 22 using HiPIMS, as described later, and the adhesion of the titanium oxide film 4 to the substrate 2 is improved.

[0097] Furthermore, before forming the protective layer 3, one side of the cured resin layer 22 in the thickness direction may be plasma-treated. A roll-to-roll sputtering deposition apparatus can be used for the plasma treatment. In other words, the plasma treatment and the formation of the protective layer 3 can be carried out continuously.

[0098] Examples of plasma treatments include plasma treatment by glow discharge, plasma treatment by a low-inductance antenna, and plasma treatment by atmospheric pressure plasma. Plasma treatment by glow discharge is preferred. The following conditions can be adjusted as appropriate depending on the plasma treatment method.

[0099] Specifically, under vacuum conditions, an inert gas and / or a reactive gas are introduced into the plasma processing chamber of the sputtering deposition apparatus, and a voltage is applied to generate plasma, thereby plasma-treating one side of the cured resin layer 22 in the thickness direction.

[0100] Examples of inert gases used in plasma processing include nitrogen, argon, krypton, xenon, and mixtures thereof. Examples of reactive gases used in plasma processing include oxygen.

[0101] The achievable vacuum level in the plasma processing chamber is, for example, 1.0 × 10⁻⁶. －４ It is less than or equal to Pa.

[0102] The atmospheric pressure inside the plasma processing chamber (the atmospheric pressure inside the plasma processing chamber when an inert gas and / or oxygen is introduced) is, for example, 0.01 Pa to 5.0 Pa, preferably 0.05 Pa to 3.0 Pa, more preferably 0.10 Pa to 1.0 Pa, and even more preferably 0.15 Pa to 0.80 Pa.

[0103] The discharge power in the plasma processing chamber is, for example, 0.01 kW to 10 kW, preferably 0.05 kW to 5 kW.

[0104] <Third Step> In the third step, as shown in Figure 2C, a titanium oxide film 4 is formed on one side of the protective layer 3 in the thickness direction.

[0105] One method for forming the titanium oxide film 4 is a dry coating method. Examples of dry coating methods include vacuum deposition, sputtering, and ion plating. Sputtering is preferred.

[0106] Examples of sputtering methods include two-electrode sputtering, ECR (electron cyclotron resonance) sputtering, magnetron sputtering, and ion beam sputtering. Preferably, reactive sputtering using the magnetron sputtering method is used.

[0107] In the third step, a sputtering deposition apparatus capable of performing the film deposition process using a roll-to-roll method is used. When a roll-to-roll sputtering deposition apparatus is used in the third step, the work film W (substrate 2 with protective layer 3) travels from the feed roll to the winding roll of the sputtering deposition apparatus, and a titanium oxide film 4 is deposited on one side of the protective layer 3 in the thickness direction. The travel speed of the work film W (substrate 2 with protective layer 3) is, for example, 0.1 to 10.0 m / min.

[0108] In the sputtering method, specifically, a sputtering gas is introduced into the deposition chamber of a sputtering deposition apparatus under vacuum conditions, while a negative voltage is applied to the target inside the chamber. This generates a glow discharge, ionizing the gas atoms, which are then collided with the target surface at high speed. The target material is ejected from the target surface and deposited in the thickness direction. Titanium (Ti) is used as the target.

[0109] Examples of sputtering gases include inert gases and reactive gases. Examples of inert gases include argon, krypton, xenon, and mixtures thereof, with argon being preferred. Examples of reactive gases include oxygen. In the reactive sputtering method, for example, oxygen is introduced into the deposition chamber in addition to the inert gas. In other words, the titanium oxide film 4 is deposited in the presence of an inert gas and oxygen.

[0110] The volume ratio of oxygen to the total volume of inert gas and oxygen introduced into the film deposition chamber is, for example, 0.01% to 30% by volume, preferably 0.1% to 20% by volume, more preferably 1% to 10% by volume, and even more preferably 2% to 5% by volume.

[0111] The achievable vacuum level in the deposition chamber before sputter deposition, and the atmospheric pressure in the deposition chamber (atmospheric pressure when inert gas and / or oxygen are introduced) are the same as in the second step described above.

[0112] The film formation temperature (the temperature of the roll supporting the substrate 2 equipped with the protective layer 3) is 70°C or higher, preferably 80°C or higher, more preferably 100°C or higher, and also 130°C or lower, preferably 120°C or lower, more preferably 110°C or lower.

[0113] If the film deposition temperature is above the lower limit mentioned above, the refractive index of the titanium oxide film 4 will increase. Also, in the electron diffraction pattern observed with a transmission electron microscope, Ti ２ O ３ A titanium oxide film 4 containing crystals in which diffraction spots appear is formed.

[0114] In the third step, high-power impulse magnetron sputtering (HiPIMS) is used as the power source for applying voltage to the target.

[0115] In HiPIMS, specifically, a voltage is applied to the target at a predetermined frequency and pulse width, generating a high-density plasma. This high-density plasma ionizes gas atoms, and the gas ions collide with the target surface at high speed, ejecting the target material from the target surface. This ejected target material is then deposited in the thickness direction.

[0116] In the third step, a titanium oxide film 4 is formed using HiPIMS, and the electron diffraction pattern observed with a transmission electron microscope shows that Ti ２ O ３ A titanium oxide film 4 containing crystals that exhibit diffraction spots is formed, and the deposition rate of the titanium oxide film 4 is increased. Furthermore, the titanium oxide film 4 is formed without damaging the surface of the cured resin layer 22, and the adhesion of the titanium oxide film 4 to the substrate 2 is improved.

[0117] When using HiPIMS, the discharge voltage is, for example, 1000V to 2000V, preferably 1500V to 1800V.

[0118] When using HiPIMS, the frequency is, for example, 150 Hz to 300 Hz, preferably 200 Hz to 250 Hz.

[0119] When using HiPIMS, the pulse width is, for example, 10 μs to 100 μs, preferably 20 μs to 50 μs.

[0120] As described above, a titanium oxide film 4 is formed on one side of the protective layer 3 in the thickness direction.

[0121] In this manner, the laminate 1 is manufactured.

[0122] <Effects> The laminate produced by the above method shows Ti in the electron diffraction pattern observed with a transmission electron microscope. ２ O ３ The material contains crystals that exhibit diffraction spots, and its refractive index when incident with light of a wavelength of 550 nm is greater than 2.50 and less than or equal to 2.80. Therefore, when the laminate is used as an anti-reflective film, the anti-reflective film has excellent anti-reflective performance, and the laminate does not damage the substrate surface and has a high film deposition rate, resulting in excellent manufacturing efficiency of the titanium oxide film.

[0123] 3. Modifications <Modifications of the base material> In Figure 1, the base material 2 consists of a transparent resin film 21 and a cured resin layer 22 arranged on one side of the transparent resin film 21 in the thickness direction, but is not limited to this.

[0124] In other words, the base material 2 may consist only of the transparent resin film 21. Furthermore, the cured resin layer 22 may be arranged on both sides of the transparent resin film 21, one side in the thickness direction and the other side.

[0125] <Anti-reflective film> The laminate 1 described above may be one of the lamination elements of the anti-reflective film X. When the laminate 1 is one of the lamination elements of the anti-reflective film X, the titanium oxide film 4 contained in the laminate 1 is a high refractive index layer 41.

[0126] In other words, the anti-reflective film X comprises a laminate 1 and a low refractive index layer 5 in sequence toward one side in the thickness direction. More specifically, as shown in Figure 3, the anti-reflective film X comprises a laminate 1 and a low refractive index layer 5 arranged on one side of the laminate 1 in the thickness direction. In other words, the low refractive index layer 5 is in contact with the titanium oxide film 4 (high refractive index layer 41).

[0127] In other words, the anti-reflective film X comprises an alternating laminate 10 consisting of a high refractive index layer 41 and a low refractive index layer 5. To put it another way, the anti-reflective film X comprises a base material 2, a protective layer 3, and an alternating laminate 10 in order toward one side in the thickness direction. The anti-reflective film X may also comprise two or more alternating laminates 10 consisting of a high refractive index layer 41 and a low refractive index layer 5. Preferably, the anti-reflective film X comprises two alternating laminates 10.

[0128] Specifically, as shown in Figure 4, the anti-reflective film X comprises a first alternating laminate 10a having a first high refractive index layer 41a (first layer) and a first low refractive index layer 5a (second layer), and a second alternating laminate 10b having a second high refractive index layer 41b (third layer) and a second low refractive index layer 5b (fourth layer).

[0129] In the alternating laminate 10, the reflection intensity of ambient light is suppressed by the interference effect between reflected light at multiple interfaces in multiple thin layers (high refractive index layer 41 and low refractive index layer 5). Furthermore, in the alternating laminate 10, the interference effect that suppresses reflection intensity can be achieved by adjusting the optical film thickness (product of refractive index and thickness) of each thin layer. In addition, the uppermost layer of the alternating laminate 10 (the layer on the outermost side in the thickness direction) is preferably the low refractive index layer 5.

[0130] The anti-reflective film X can have a low reflectivity of ambient light by comprising two or more alternating laminates 10, each consisting of a high refractive index layer 41 and a low refractive index layer 5.

[0131] The total thickness of the alternating laminate 10 is, for example, 20 nm or more, preferably 30 nm or more, more preferably 40 nm or more, even more preferably 50 nm or more, and also, for example, 200 nm or less, preferably 100 nm or less, more preferably 80 nm or less, and even more preferably 60 nm or less.

[0132] If the total thickness of the alternating laminate 10 is greater than or equal to the lower limit value, the reflection intensity of ambient light can be suppressed. If the total thickness of the alternating laminate 10 is less than or equal to the upper limit value, cracking of the alternating laminate 10 can be suppressed.

[0133] The ratio of the thickness of the high refractive index layer 41 (total thickness) to the total thickness of the alternating laminate 10 is, for example, 10% or more, preferably 15% or more, more preferably 20% or more, even more preferably 25% or more, and also, for example, 60% or less, preferably 50% or less, and more preferably 35% or less.

[0134] The ratio of the thickness of the low refractive index layer 5 (total thickness) to the total thickness of the alternating laminate 10 is, for example, 40% or more, preferably 50% or more, more preferably 60% or more, even more preferably 65% ​​or more, and also, for example, 85% or less, preferably 80% or less, and more preferably 75% or less.

[0135] In other words, the thickness (total thickness) of the high refractive index layer 41 is preferably thinner than the thickness (total thickness) of the low refractive index layer 5.

[0136] The thickness of the anti-reflective film X is, for example, 10 μm or more, preferably 20 μm or more, more preferably 30 μm or more, even more preferably 50 μm or more, or, for example, 200 μm or less, preferably 180 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less.

[0137] <High refractive index layer> When the titanium oxide film 4 is used as the high refractive index layer 41, the thickness of the first high refractive index layer 41a (first layer) is, for example, 10 nm or more, preferably 15 nm or more, more preferably 20 nm or more, even more preferably 25 nm or more, and also, for example, 100 nm or less, preferably 50 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less.

[0138] When the titanium oxide film 4 is used as the high refractive index layer 41, the thickness of the second high refractive index layer 41b (third layer) is, for example, 10 nm or more, preferably 15 nm or more, more preferably 20 nm or more, even more preferably 25 nm or more, and also, for example, 110 nm or less, preferably 50 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less.

[0139] When the titanium oxide film 4 is used as the high refractive index layer 41, the total thickness of the high refractive index layer 41 is, for example, 20 nm or more, preferably 30 nm or more, more preferably 40 nm or more, even more preferably 50 nm or more, and also, for example, 200 nm or less, preferably 100 nm or less, more preferably 80 nm or less, and even more preferably 60 nm or less.

[0140] When the titanium oxide film 4 is used as a high refractive index layer 41, the optical film thickness (product of refractive index and thickness) of the first high refractive index layer 41a (first layer) and the optical film thickness of the second high refractive index layer 41b (third layer) are, for example, 20 nm or more and, for example, 100 nm or less.

[0141] <Low refractive index layer> The low refractive index layer 5 is a layer having a refractive index lower than that of the titanium oxide film 4.

[0142] Examples of materials for the low refractive index layer 5 include silicon oxide and magnesium fluoride. Silicon oxide is preferred. In other words, the low refractive index layer 5 is preferably a silicon oxide layer. The uppermost layer (the outermost layer in the thickness direction) of the alternating laminate 10 is preferably a silicon oxide layer. The silicon oxide layer is a layer made of silicon oxide.

[0143] When light with a wavelength of 550 nm is incident on the low refractive index layer 5, the refractive index is 1.5 or less. Furthermore, if the low refractive index layer 5 is a silicon oxide layer, the refractive index when light with a wavelength of 550 nm is incident on the silicon oxide layer is 1.46.

[0144] The thickness of the first low refractive index layer 5a (second layer) is, for example, 10 nm or more, preferably 15 nm or more, more preferably 20 nm or more, even more preferably 25 nm or more, and also, for example, 100 nm or less, preferably 50 nm or less, more preferably 40 nm or less, and even more preferably 30 nm or less.

[0145] The thickness of the second low refractive index layer 5b (fourth layer) is, for example, 70 nm or more, preferably 80 nm or more, more preferably 90 nm or more, and also, for example, 130 nm or less, preferably 120 nm or less, more preferably 110 nm or less, and even more preferably 105 nm or less.

[0146] The optical film thickness of the first low refractive index layer 5a (second layer) is, for example, 30 nm or more, or, for example, 50 nm or less. The optical film thickness of the second low refractive index layer 5b (fourth layer) is, for example, 120 nm or more, or, for example, 160 nm or less.

[0147] <Method for manufacturing the low refractive index layer> The low refractive index layer 5 is formed on one side in the thickness direction of the high refractive index layer 41 (titanium oxide film 4).

[0148] One method for forming the low refractive index layer 5 is sputtering.

[0149] In the sputtering method, a sputtering deposition apparatus capable of performing the film deposition process in a roll-to-roll manner can be used. When a roll-to-roll sputtering deposition apparatus is used to form the low refractive index layer 5, the work film W (laminated 1) is moved from the feed roll to the winding roll of the sputtering deposition apparatus, and the material for the low refractive index layer 5 is deposited on one side in the thickness direction of the high refractive index layer 41. The travel speed of the work film W (laminated 1) is, for example, 0.1 to 10.0 m / min.

[0150] In the sputtering method, it is preferable to use a sputtering deposition apparatus equipped with a plurality of deposition chambers arranged sequentially along the travel path of the work film W (substrate 2 equipped with a protective layer 3), and to form the first to fourth layers in order.

[0151] In the sputtering method, specifically, a sputtering gas is introduced into the deposition chamber of a sputtering deposition apparatus under vacuum conditions, while a negative voltage is applied to a target made of the low refractive index layer 5 material inside the deposition chamber. This generates a glow discharge, ionizing the gas atoms, which then collide with the target surface at high speed, ejecting the target material from the target surface. This ejected target material is then deposited sequentially in the thickness direction. Silicon is one example of a target material.

[0152] Examples of sputtering gases include inert gases and reactive gases. Examples of inert gases include argon, krypton, xenon, and mixtures thereof, with argon being preferred. Examples of reactive gases include oxygen. The low refractive index layer 5 is formed in the presence of an inert gas and oxygen.

[0153] The achievable vacuum level inside the deposition chamber is, for example, 1.0 × 10⁻⁶. －４ It is less than or equal to Pa.

[0154] The volume ratio of oxygen to the total volume of inert gas and oxygen introduced into the film deposition chamber is, for example, 0.01% to 30% by volume, preferably 0.1% to 20% by volume, more preferably 1% to 10% by volume, and even more preferably 2% to 5% by volume.

[0155] The film formation temperature (the temperature of the rolls supporting the laminate 1 when the low refractive index layer 5 is formed) is, for example, -50.0°C to 30.0°C, preferably -30.0°C to 20.0°C, more preferably -20.0°C to 10.0°C, and even more preferably -15.0°C to 0.0°C.

[0156] The atmospheric pressure inside the deposition chamber (the atmospheric pressure inside the deposition chamber when inert gas and oxygen are introduced) is, for example, 0.01 Pa to 5.0 Pa, preferably 0.05 Pa to 3.0 Pa, more preferably 0.10 Pa to 1.0 Pa, and even more preferably 0.15 Pa to 0.80 Pa.

[0157] Examples of power supplies for applying voltage to the target include DC power supplies, AC power supplies, MF power supplies, and RF power supplies. An MFAC power supply, which combines an MF power supply and an AC power supply, may also be used. Preferably, an MFAC power supply is used.

[0158] The discharge power is, for example, 1 kW to 20 kW, preferably 3 kW to 10 kW.

[0159] The present invention will be described in more detail below with reference to examples, comparative examples, and reference examples. However, the present invention is not limited to the examples, comparative examples, and reference examples. Furthermore, specific numerical values ​​such as blending ratios (content ratios), physical properties, and parameters used in the following description may be replaced with the upper limits (numerical values ​​defined as "less than or equal to" or "less than") or lower limits (numerical values ​​defined as "greater than or equal to" or "greater than") of the corresponding blending ratios (content ratios), physical properties, and parameters described in the "Modes for Carrying Out the Invention" above.

[0160] <Fabrication of Laminate> Example 1 The laminate of Example 1 was fabricated as shown below.

[0161] [Step 1] 100 parts by mass of a butyl acetate solution of UV-curable acrylic urethane resin (product name: Luxidia 17-806, solid content concentration: 80% by mass, manufactured by DIC Corporation), 5 parts by mass of a photopolymerization initiator (product name: IRGACURE 906, manufactured by BASF Corporation), and 0.01 parts by mass of a leveling agent (product name: GRANDIC PC4100, manufactured by DIC Corporation) were mixed to obtain a mixture. Subsequently, the solid content concentration of the mixture was adjusted to 36% by mass by adding a mixed solvent of cyclopentanone (CPN) and propylene glycol monomethyl ether (PGM) (mass ratio of CPN to PGM: 45:55) to obtain a curable resin composition. This curable resin composition was applied to one side in the thickness direction of an 80 μm thick triacetylcellulose (TAC) film (product name: KC8UA, manufactured by Konica Minolta Advanced Layer Co., Ltd.) so that the thickness after drying was 7 μm, and dried at 90°C for 1 minute. After that, a high-pressure mercury lamp was used to apply light at a wavelength of 365 nm and an integrated light intensity of 300 mJ / cm². ２ The coated layer was cured by irradiation with ultraviolet light to form a cured resin layer. In this way, a TAC film (substrate) having a cured resin layer was obtained.

[0162] [Second Step] Next, a silicon layer (protective layer) with a thickness of 60 nm was formed on one side in the thickness direction of the cured resin layer. In the second step, a roll-to-roll magnetron sputter deposition apparatus was used. The sputter deposition apparatus is equipped with a deposition chamber that can carry out the deposition process while the work film is being moved in a roll-to-roll manner. In the second step, the ultimate vacuum level in the deposition chamber of the sputter deposition apparatus was 1.0 × 10⁻⁶. －４ After evacuating the chamber to a pressure of Pa, argon was introduced as an inert gas into the deposition chamber to set the atmospheric pressure to 0.2 Pa. Silicon was used as the target. An MFAC power supply was used to apply voltage to the target, with a discharge power of 3.0 kW, and the deposition temperature (temperature of the roll supporting the work film) was set to room temperature. In this way, a silicon layer (protective layer) was formed on one side in the thickness direction of the cured resin layer.

[0163] [Third Step] Next, a 50 nm thick titanium oxide film was formed on one side in the thickness direction of the silicon layer (protective layer). In the third step, a roll-to-roll magnetron sputter deposition apparatus was used. The sputter deposition apparatus is equipped with a deposition chamber that allows the deposition process to be carried out while the work film is moved in a roll-to-roll manner. In the third step, the ultimate vacuum level in the deposition chamber of the sputter deposition apparatus was 1.0 × 10⁻⁶. －４ After evacuating the chamber to a pressure of Pa, argon as an inert gas and oxygen as a reactive gas were introduced into the deposition chamber to set the atmospheric pressure to 0.2 Pa. The argon and oxygen were introduced into the deposition chamber in a volume ratio of 100:5. Titanium was used as the target. A HiPIMS (product name: TruPlasma Highpulse 4002 G2, manufactured by Trumpf) was used as the power supply for applying voltage to the target, with a discharge voltage of 1700 V, a frequency of 210 Hz, and a pulse width of 35 μs. The deposition temperature (temperature of the rolls supporting the work film) was set to 100 °C. In the third step, the deposition time was determined by dividing the length of the roll opening (the part of the roll exposed to the plasma in the sputter deposition apparatus) by the running speed of the work film. In this way, a titanium oxide film was formed on one side in the thickness direction of the silicon layer (protective layer), and a laminate was fabricated.

[0164] In Example 2, the laminate of Example 2 was fabricated in the same manner as the laminate of Example 1, except that in the second step, argon as an inert gas and oxygen as a reactive gas were introduced into the deposition chamber, and the volume ratio of argon to oxygen was 100:30.

[0165] Example 3 In the third step, the laminate of Example 3 was fabricated in the same manner as the laminate of Example 1, except that the film deposition temperature was set to 70°C.

[0166] Comparative Example 1 was carried out in the same manner as in Example 1, except that the second step was not performed.

[0167] Comparative Example 2: In the third step, argon and oxygen were introduced into the deposition chamber in a volume ratio of 100:10. A DC power supply was used as the power source for applying voltage to the target, and the discharge power was set to 3.0 kW. Except for these differences, the laminate of Comparative Example 2 was fabricated in the same manner as the laminate of Example 1.

[0168] Comparative Example 3: In the third step, the laminate of Comparative Example 3 was prepared in the same manner as the laminate of Example 1, except that the film deposition temperature was set to room temperature.

[0169] Comparative Example 4: In the first step, alkali-free glass was prepared instead of the TAC film having a cured resin layer, the second step was omitted, and in the third step, a batch-type magnetron sputtering deposition apparatus was used to form the titanium oxide film, and the deposition temperature was set to room temperature. Except for these differences, the laminate of Comparative Example 4 was prepared in the same manner as the laminate of Example 1.

[0170] <Measurement of Refractive Index> The titanium oxide film contained in the laminates obtained in each example and comparative example was measured using a spectroscopic ellipsometer (product name: RC2, manufactured by J.A. Wollam Japan). After measurement, the refractive index was determined by fitting the measured spectra with the polarization analysis parameters ψ and Δ to the simulation spectra calculated from the optical model. As the optical model, a laminated structure consisting of a film, a protective layer, and a titanium oxide film was set, and the titanium oxide film was fitted using Cauchy's dispersion formula. The results are shown in Table 1.

[0171] <Analysis of Electron Diffraction Patterns> Cross-sections of the titanium oxide film contained in the laminates obtained in each example and comparative example were prepared at specified locations using the FIB microsampling method, and the cross-sections were observed using an FE-TEM (product name: JEM-2800, manufactured by JEOL). After obtaining electron diffraction patterns from the cross-sections of the titanium oxide film, the constituent layers of the titanium oxide film were analyzed from the interplanar spacing of the electron diffraction spots and the interplanar spacing on the ICDD data. The results are shown in Table 1.

[0172] <Calculation of Film Deposition Rate> For the titanium oxide film contained in the laminates obtained in each example and comparative example, the film thickness was determined from cross-sectional observation using FE-TEM, and the film deposition rate was calculated by dividing it by the film deposition time described above. The results are shown in Table 1.

[0173] <Discussion> The laminates of Examples 1 to 3 are arranged in order from a substrate, a protective layer, and a titanium oxide film toward one side in the thickness direction, and the titanium oxide film is Ti as observed in the electron diffraction pattern when viewed with a transmission electron microscope. ２ O ３ The laminates contain crystals that exhibit diffraction spots, and the refractive index when incident with light of a wavelength of 550 nm is greater than 2.50 and less than or equal to 2.80. Therefore, when the laminates of Examples 1 to 3 are used as anti-reflective films, the anti-reflective films have excellent anti-reflective performance, and the laminates of Examples 1 to 3 do not damage the substrate surface and have a high film deposition rate, resulting in excellent manufacturing efficiency of titanium oxide films.

[0174] The laminate of Comparative Example 1 does not have a protective layer. Therefore, the laminate of Comparative Example 1 is damaged on the surface of the substrate by film formation using HiPIMS, making it impossible to deposit a titanium oxide film.

[0175] In the laminate of Comparative Example 2, the titanium oxide film was not deposited by HiPIMS. Therefore, the titanium oxide film was not present in the electron diffraction pattern observed with a transmission electron microscope. ２ O ３ It does not contain crystals in which diffraction spots appear, and the deposition rate of titanium oxide films is low.

[0176] In the laminate of Comparative Example 3, the deposition temperature for the titanium oxide film was less than 70°C. Therefore, the titanium oxide film showed Ti in the electron diffraction pattern observed with a transmission electron microscope. ２ O ３ The laminate does not contain crystals that exhibit diffraction spots, and its refractive index does not exceed 2.50 when light with a wavelength of 550 nm is incident on it. Therefore, when the laminate of Comparative Example 3 is used as an anti-reflective film, the anti-reflective film has inferior anti-reflective performance.

[0177] In the laminate of Comparative Example 4, the deposition temperature for the titanium oxide film was less than 70°C, and a roll-to-roll magnetron sputter deposition apparatus was not used. Therefore, the titanium oxide film showed Ti in the electron diffraction pattern observed with a transmission electron microscope. ２ O ３ It does not contain crystals in which diffraction spots appear, and the deposition rate of titanium oxide films is low.

[0178]

[0179] The above invention is provided as an illustrative embodiment of the present invention, but this is merely illustrative and should not be interpreted restrictively. Modifications of the present invention that are obvious to those skilled in the art are included in the claims below.

[0180] The laminate of the present invention can be used, for example, as a film placed on the outermost surface of a display screen in an image display device such as a liquid crystal display or an organic EL display.

[0181] 1. Laminate 2. Substrate 3. Protective layer 4. Titanium oxide film 5. Low refractive index layer 10. Alternating laminate 21. Transparent resin film 22. Cured resin layer X. Anti-reflective film

Claims

The substrate, protective layer, and titanium oxide film are arranged in order toward one side in the thickness direction. The titanium oxide film is observed in the electron diffraction pattern using a transmission electron microscope, and Ti ２ O ３ The crystal contains the diffraction spot group that appears, A laminate in which the refractive index when incident on light with a wavelength of 550 nm is greater than 2.50 and less than or equal to 2.

80. The laminate according to claim 1, wherein the refractive index is greater than 2.

68. A method for manufacturing a laminate according to claim 1, The first step is to prepare the aforementioned substrate, A second step involves forming the protective layer on one side in the thickness direction of the substrate, A method for manufacturing a laminate, comprising a third step of forming the titanium oxide film on one side of the thickness direction of the protective layer using high-power impulse magnetron sputtering (HiPIMS) at a film formation temperature of 70°C or higher. 　 The method for manufacturing a laminate according to claim 3, wherein the third step is carried out with the film formation temperature set to 100°C or higher. 　 The method for manufacturing a laminate according to claim 3 or 4, wherein the second step and the third step are carried out in a roll-to-roll manner. 　 The laminate according to claim 1 or 2 and a low refractive index layer having a refractive index smaller than that of the titanium oxide film are provided sequentially toward one side in the thickness direction, The titanium oxide film is an anti-reflective film with a high refractive index. 　 The anti-reflective film according to claim 6, comprising two or more alternating laminates consisting of the high refractive index layer and the low refractive index layer.

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