Anti-reflective film and method for manufacturing anti

Abstract

An anti-reflection film (1) is provided with a transparent base film (2), an anti-reflection layer (3), and an antifouling layer (4) in this order toward one side in the thickness direction. The transparent substrate film (2) is provided with a transparent resin film (21). The anti-reflection layer (3) is an alternating laminate comprising at least one niobium oxide layer (31) and at least one silicon oxide layer (32), and the layer of the anti-reflection layer (3) closest to the antifouling layer (4) is the silicon oxide layer (32). Furthermore, in a difference spectrum calculated from Fourier transform infrared spectrophotometer analysis (FT-IR analysis), when the maximum absorption peak intensity originating from Si-O-Si symmetric scaling near 1050 cm <-1 > is standardized to 1 and the absorption peak intensity originating from Si-O-Si asymmetric scaling at 1200 cm <-1 > is defined as X, 1 / X is 5.0 or more.

Description

Technical Field

[0001] This invention relates to an anti-reflective film and a method for manufacturing the anti-reflective film. Background Technology

[0002] In image display devices such as liquid crystal displays (LCDs) and organic electroluminescent (EL) displays, an anti-reflective film is placed on the outermost surface of the display screen to prevent external light from entering. Such an anti-reflective film comprises a transparent substrate film and an anti-reflective layer formed by a high-refractive-index layer and a low-refractive-index layer.

[0003] In addition, in order to suppress the adhesion of pollutants, an anti-reflective film with an anti-fouling layer has been proposed (for example, see Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2022-079332 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] On the other hand, since the anti-reflective film is placed on the outermost surface of the display screen, it requires even better scratch resistance.

[0009] This invention provides an anti-reflective film with excellent scratch resistance and a method for manufacturing the anti-reflective film.

[0010] Solution for solving the problem

[0011] The present invention [1] includes an anti-reflective film, wherein the anti-reflective film comprises, sequentially on one side facing the thickness direction, a transparent substrate film, an anti-reflective layer, and an anti-fouling layer, the transparent substrate film comprising a transparent resin film, the anti-reflective layer being an alternating laminate formed of at least one niobium oxide layer and at least one silicon oxide layer, wherein the layer in the anti-reflective layer closest to the anti-fouling layer is a silicon oxide layer, and in the difference spectrum calculated according to the Fourier transform infrared spectrophotometer analysis (FT-IR analysis) described below, 1050 cm⁻¹ －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value. －1 When the intensity of the absorption peak originating from the asymmetric stretching of Si-O-Si is set to X, 1 / X is greater than 5.0.

[0012] (FT-IR analysis)

[0013] Infrared absorption spectrum S1 was measured from the thickness direction side of the antireflection film using the total internal reflection method of a Fourier transform infrared spectrophotometer. In addition, infrared absorption spectrum S2 was measured from the thickness direction side of the sample film obtained by removing the antireflection layer and the antifouling layer from the antireflection film using the total internal reflection method of a Fourier transform infrared spectrophotometer. The difference spectrum between infrared absorption spectrum S1 and infrared absorption spectrum S2 was calculated.

[0014] The present invention [2] includes the antireflective film described in [1], wherein the transparent substrate film further comprises a cured resin layer disposed on one side of the thickness direction of the transparent resin film.

[0015] The present invention [3] includes the antireflective film described in [1] or [2], wherein the antireflective film further comprises a primer layer disposed between the transparent substrate film and the antireflective layer, the primer layer being a metal oxide layer.

[0016] The present invention [4] includes any one of [1] to [3] antireflective film, wherein the indentation elastic modulus of 10 nm on one side of the thickness direction of the antifouling layer is 16 GPa or more.

[0017] The present invention [5] includes a method for manufacturing an antireflective film, which is a method for manufacturing an antireflective film as described in any one of [1] to [4], wherein the antireflective layer is formed on one side of the thickness direction of the transparent substrate film by sputtering, and the silicon oxide layer of the antireflective layer closest to the antifouling layer is formed by sputtering at a sputtering angle of 35 degrees or less.

[0018] The present invention [6] includes a method for manufacturing an antireflective film as described in [5], wherein the silicon oxide layer closest to the antifouling layer is formed by reactive sputtering, and in the formation of the silicon oxide layer closest to the antifouling layer using the reactive sputtering method, oxygen is introduced using an impedance control method or a PEM control method to form a film in the transition region between the metal region and the oxide region.

[0019] Invention Effects

[0020] The antireflective film of the present invention, in the difference spectrum calculated based on Fourier transform infrared spectrophotometry (FT-IR analysis), shows a 1050 cm⁻¹ value. －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value. －1 When the absorption peak intensity originating from the asymmetric stretching of Si-O-Si is set as X, 1 / X is greater than 5.0. Therefore, compared with the structure with asymmetric stretching of Si-O-Si, the proportion of structures with symmetric stretching of Si-O-Si is higher, resulting in excellent scratch resistance.

[0021] The method for manufacturing the antireflective film of the present invention involves forming a silicon oxide layer, the layer closest to the antifouling layer in the antireflective layer, using a sputtering method with a sputtering angle of 35 degrees or less. Therefore, an antireflective film with excellent scratch resistance can be manufactured. Attached Figure Description

[0022] Figure 1 This is a cross-sectional view showing one embodiment of the antireflective film of the present invention.

[0023] Figure 2 express Figure 1 The manufacturing method of the anti-reflective film is shown in the figure. Figure 2 2A indicates the process of preparing the transparent resin film. Figure 2 2B indicates the process of forming a cured resin layer on a transparent resin film. Figure 2 2C indicates the process of forming a primer layer on the cured resin layer. Figure 2 The 2D designation indicates the process of forming an alternating laminate of niobium oxide and silicon oxide layers on a primer layer. Figure 2 2E indicates the process of forming an antifouling layer on a silicon oxide layer.

[0024] Figure 3 A schematic diagram showing the configuration of a magnetron sputtering film deposition apparatus used in a method for manufacturing antireflective films.

[0025] Figure 4 express Figure 3 The image shows an enlarged cross-sectional view of the magnetron plasma unit in the magnetron sputtering film deposition apparatus.

[0026] Figure 5 This is a cross-sectional view showing the magnet unit of the first magnetized plasma unit.

[0027] Figure 6 This is a cross-sectional view showing the magnet unit of the second magnetized plasma unit. Detailed Implementation

[0028] 1. Anti-reflective film

[0029] Reference Figure 1 One embodiment of the antireflective film of the present invention will be described.

[0030] like Figure 1 As shown, the antireflective film 1 has a film shape (including a sheet shape) with a specified thickness. Furthermore, the antireflective film 1 extends in a plane direction orthogonal to the thickness direction, and the surface of the antireflective film 1 on one side of the thickness direction (upper surface) and the surface on the other side of the thickness direction (lower surface) are flat.

[0031] The anti-reflective film 1 comprises, on its thickness-oriented side, a transparent substrate film 2, an anti-reflective layer 3, and an anti-fouling layer 4. The anti-reflective film 1 may also include a primer layer 5 disposed between the transparent substrate film 2 and the anti-reflective layer 3. Specifically, as... Figure 1 As shown, the antireflective film 1 includes a transparent substrate film 2, a primer layer 5 disposed on one side of the transparent substrate film 2 in the thickness direction, an antireflective layer 3 disposed on one side of the primer layer 5 in the thickness direction, and an antifouling layer 4 disposed on one side of the antireflective layer 3 in the thickness direction.

[0032] <Transparent substrate film>

[0033] The transparent substrate film 2 is the bottom layer of the antireflective film 1. Furthermore, the transparent substrate film 2 includes a transparent resin film 21. Additionally, the transparent substrate film 2 may also include a cured resin layer 22 disposed on one side of the transparent resin film 21 in the thickness direction. Preferably, the transparent substrate film 2 includes 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 preferably, it is composed of 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.

[0034] The transparent resin film 21 has a film shape (including a sheet shape). Furthermore, the transparent resin film 21 may be, for example, a flexible, transparent resin film.

[0035] 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, polyaryl ester 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 cyclic olefin polymers (COP). Examples of cellulose resins include cellulose triacetate (TAC). From the viewpoints of transparency, heat resistance, and mechanical strength, the transparent resin film 21 is preferably a cellulose-based film formed from cellulose resin. Cellulose triacetate films are more preferably used. It should be noted that the materials for the transparent resin film 21 can be used alone or in combination of two or more.

[0036] The total light transmittance (JISK-7105) of 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, for example, 100% or less.

[0037] The thickness of the transparent resin film 21 is not particularly limited, but from the viewpoint of strength and operability, it is, for example, 5 μm or more, preferably 10 μm or more, more preferably 20 μm or more, further preferably 30 μm or more, especially preferably 50 μm or more. In addition, it is, for example, 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, further preferably 150 μm or less, especially preferably 100 μm or less.

[0038] It should be noted that the thickness of the transparent resin film 21 can be measured, for example, using a film thickness gauge.

[0039] The cured resin layer 22 is a layer that improves the mechanical properties of the antireflective film 1. The cured resin layer 22 is in contact with one side of the transparent resin film 21 in the thickness direction.

[0040] Examples of curable resin layers 22 include hard coatings and anti-adhesion layers. A hard coating is, for example, a layer that does not easily cause scratches on the exposed surface of the transparent resin film 21. An anti-adhesion layer is, for example, a layer that imparts anti-adhesion properties to the surfaces of multiple anti-reflective films 1 in contact with each other, when the anti-reflective films 1 are stacked along the thickness direction.

[0041] 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 coating a curable resin composition onto one side of the transparent resin film 21 in the thickness direction, drying it as needed, and then curing it.

[0042] The curable resin composition contains a curable resin. Examples of curable resins include polyester resins, urethane acrylate resins, acrylic resins (excluding urethane acrylate resins), urethane resins (excluding urethane acrylate resins), amide resins, silicone resins, epoxy resins, and melamine resins. Preferably, urethane acrylate resins and acrylic resins (excluding urethane acrylate resins) are examples. The curable resin can be used alone or in combination of two or more. Preferably, two or more are used in combination.

[0043] Furthermore, examples of curable resin compositions include, for instance, UV-curable resin compositions and thermosetting resin compositions. From the viewpoint of manufacturing efficiency, UV-curable resin compositions are preferred as curable resin compositions. UV-curable resin compositions contain at least one component selected from the group consisting of UV-curable monomers, UV-curable oligomers, and UV-curable polymers. A specific example of a UV-curable resin composition is the hard coating forming composition disclosed in Japanese Patent Application Publication No. 2016-179686.

[0044] From the viewpoint of adjusting the hardness, surface roughness, refractive index, and imparting anti-glare properties of the cured resin layer 22, the curable resin composition preferably contains microparticles. Examples of microparticles include inorganic and organic particles. Inorganic particles are preferred. Examples of inorganic particles include inorganic oxide particles. Examples of inorganic oxide particles include silica, alumina, titanium dioxide, zirconium oxide, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. Silica is preferred. Examples of organic particles include polymethyl methacrylate, polystyrene, polyurethane, acrylic / styrene copolymer, benzoguanamine, melamine, and polycarbonate.

[0045] Furthermore, when the curable resin composition is a UV-curable resin composition, it is preferable to include a photopolymerization initiator.

[0046] Furthermore, the curable resin composition may contain additives such as solvents, leveling agents, thixotropic agents, and antistatic agents.

[0047] Examples of solvents include butyl acetate, ethyl acetate, toluene, and cyclopentanone. Butyl acetate is a preferred solvent.

[0048] The thickness of the cured resin layer 22 is, for example, 0.1 μm or more, preferably 0.5 μm or more, more preferably 1 μm or more, and furthermore, for example, 15 μm or less, preferably 12 μm or less, more preferably 10 μm or less.

[0049] If the thickness of the cured resin layer 22 is above or above the aforementioned lower limit, the cured resin layer 22 can be easily formed, and its function can be fully realized. Furthermore, if the thickness of the cured resin layer is below or below the aforementioned upper limit, the antireflective film 1 can be made thinner.

[0050] From the viewpoint of improving adhesion to the primer layer 5 (described later) or the antireflective layer 3 (described later), the side of the transparent substrate film 2 in the thickness direction (the side of the cured resin layer 22 in the thickness direction) can be surface modified. Surface modification is preferred. Examples of surface modification treatments include corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, glow discharge treatment, saponification treatment, and treatment using coupling agents. Plasma treatment is preferred.

[0051] The total light transmittance (JISK-7105) of the transparent substrate film 2 is, for example, 80% or more, preferably 85% or more, more preferably 88% or more, even more preferably 90% or more, and, for example, 100% or less.

[0052] The thickness of the transparent substrate film 2 is not particularly limited, but from the viewpoint of strength and operability, it is, for example, 5 μm or more, preferably 10 μm or more, more preferably 20 μm or more, further preferably 30 μm or more, especially preferably 50 μm or more. In addition, it is, for example, 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, further preferably 150 μm or less, especially preferably 100 μm or less.

[0053] <Primer Layer>

[0054] The primer layer 5 is an adhesive layer that improves the adhesion of the antireflective layer 3 laminated on the transparent substrate film 2. The primer layer 5 is disposed on one side of the thickness direction of the transparent substrate film 2 and the other side of the thickness direction of the antireflective layer 3. Specifically, as... Figure 1 As shown, the primer layer 5 is disposed on one side of the transparent substrate film 2 in the thickness direction (the side of the cured resin layer 22 in the thickness direction). That is, the primer layer 5 is in contact with the transparent substrate film 2 (cured resin layer 22).

[0055] Materials used as primer layer 5 may include, for example, metals such as nickel, chromium, indium, aluminum, tin, gold, silver, platinum, zinc, titanium, tungsten, zirconium, palladium, alloys of two or more of these metals, and oxides of these metals. Furthermore, materials used as primer layer 5 may include, for example, quasi-metals such as silicon and their oxides.

[0056] Examples of conductive oxides containing metals include indium-containing conductive oxides, antimony-containing conductive oxides, and zinc-containing conductive oxides. Examples of indium-containing conductive oxides include indium-tin oxide (ITO), indium-zinc oxide (IZO), indium-gallium oxide (IGO), and indium-gallium-zinc oxide (IGZO). Examples of antimony-containing conductive oxides include antimony-tin oxide (ATO). Examples of zinc-containing conductive oxides include zinc-aluminum oxide (AZO).

[0057] The material of the primer layer 5 is preferably an inorganic oxide containing at least one element selected from the group consisting of silicon, indium, aluminum, tin, titanium, and zirconium. From the viewpoint of adhesion between the transparent substrate film 2 and the anti-reflective layer 3 laminated on the primer layer 5, the material of the primer layer 5 is more preferably a metal oxide, and even more preferably indium tin oxide (ITO). In other words, the primer layer 5 is more preferably a metal oxide layer, and even more preferably an ITO layer.

[0058] In the ITO material used as the primer layer, the content of tin oxide relative to the total amount of indium oxide and tin oxide is, for example, 1% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more. In addition, it is, for example, 50% by mass or less, preferably 45% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less.

[0059] The thickness of the primer layer 5 is, for example, 0.1 nm or more, preferably 0.5 nm or more, more preferably 1.0 nm or more, even more preferably 2.0 nm or more, especially preferably 3.0 nm or more, and also, for example, 30.0 nm or less, preferably 20.0 nm or less, more preferably 15.0 nm or less, even more preferably 10.0 nm or less, especially preferably 8.0 nm or less.

[0060] If the thickness of the primer layer 5 is above the aforementioned lower limit, the adhesion between the transparent substrate film 2 and the anti-reflective layer 3 laminated on the primer layer 5 can be ensured.

[0061] <Anti-reflective layer>

[0062] The anti-reflective layer 3 is a layer that suppresses the intensity of external light reflection. The anti-reflective layer 3 is disposed on one side of the transparent substrate film 2 in the thickness direction. Specifically, the anti-reflective layer 3 is disposed on one side of the primer layer 5 in the thickness direction. That is, the anti-reflective layer 3 is in contact with the primer layer 5.

[0063] The antireflective layer 3 is an alternating stack of a high-refractive-index layer with a relatively high refractive index and a low-refractive-index layer with a relatively low refractive index. In the antireflective layer 3, the intensity of external light reflection is suppressed through interference between reflected light at multiple interfaces of the multiple thin layers (high-refractive-index layer and low-refractive-index layer). Furthermore, in the antireflective layer 3, the interference effect of suppressing reflection intensity can be achieved by adjusting the optical film thickness (the product of refractive index and thickness) of each thin layer.

[0064] Specifically, the antireflective layer 3 is an alternating laminate formed of at least one niobium oxide layer 31 and at least one silicon oxide layer 32. The niobium oxide layer 31 corresponds to a high refractive index layer, and the silicon oxide layer 32 corresponds to a low refractive index layer. Furthermore, the layer in the antireflective layer 3 closest to the antifouling layer 4 is the silicon oxide layer 32. In other words, the uppermost layer of the antireflective layer 3 (the layer disposed on the farthest side in the thickness direction) is the silicon oxide layer 32. Moreover, it is preferable that the layer in the antireflective layer 3 closest to the transparent substrate film 2 is the niobium oxide layer 31. In other words, it is preferable that the lowermost layer of the antireflective layer 3 (the layer disposed on the farthest side in the thickness direction) is the niobium oxide layer 31.

[0065] More specifically, such as Figure 1As shown, in one embodiment of the antireflective film, the antireflective layer 3 is an alternating stack of niobium oxide layer 31a (first layer), silicon oxide layer 32a (second layer), niobium oxide layer 31b (third layer) and silicon oxide layer 32b (fourth layer).

[0066] In one embodiment of the antireflective film, such as Figure 1 As shown, the niobium oxide layer 31a (first layer) is in contact with the primer layer 5. The niobium oxide layer 31a (first layer) is in contact with the silicon oxide layer 32a (second layer). The silicon oxide layer 32a (second layer) is in contact with the niobium oxide layer 31b (third layer). The niobium oxide layer 31b (third layer) is in contact with the silicon oxide layer 32b (fourth layer). The layer in the anti-reflective layer 3 closest to the antifouling layer 4 is the silicon oxide layer 32b (fourth layer).

[0067] The niobium oxide layer 31 is a layer formed of niobium oxide. Furthermore, the silicon oxide layer 32 is a layer formed of silicon oxide. It should be noted that the niobium oxide layer 31 and the silicon oxide layer 32 may contain trace amounts of unavoidable impurities.

[0068] As described above, the niobium oxide layer 31 is a layer with a relatively high refractive index, while the silicon oxide layer 32 is a layer with a relatively low refractive index. Specifically, the niobium oxide layer 31 has a refractive index of 2.33 at a wavelength of 550 nm. Furthermore, the silicon oxide layer 32 has a refractive index of 1.46 at a wavelength of 550 nm.

[0069] The thickness of the niobium oxide layer 31a (first layer) is, for example, 1 nm or more, preferably 3 nm or more, more preferably 5 nm or more, and even more preferably 10 nm or more. In addition, it is, for example, 50 nm or less, preferably 30 nm or less, more preferably 25 nm or less, and even more preferably 20 nm or less.

[0070] The thickness of the niobium oxide layer 31b (third layer) is, for example, 5 nm or more, preferably 10 nm or more, more preferably 15 nm or more, and even more preferably 20 nm or more. In addition, it is, for example, 200 nm or less, preferably 100 nm or less, more preferably 60 nm or less, and even more preferably 40 nm or less.

[0071] The total thickness of the niobium oxide layer 31 is, for example, 1 nm or more, preferably 5 nm or more, more preferably 10 nm or more, even more preferably 20 nm or more, especially preferably 30 nm or more, and in addition, for example, 300 nm or less, preferably 200 nm or less, more preferably 100 nm or less, even more preferably 80 nm or less, especially preferably 60 nm or less.

[0072] In the case where the alternating laminate has a niobium oxide layer 31a (first layer) and a niobium oxide layer 31b (third layer), the thickness of the niobium oxide layer 31a (first layer) is preferably thinner than the thickness of the niobium oxide layer 31b (third layer).

[0073] The thickness of the silicon oxide layer 32a (second layer) is, for example, 10 nm or more, preferably 20 nm or more, more preferably 30 nm or more, and furthermore, for example, 300 nm or less, preferably 200 nm or less, more preferably 150 nm or less.

[0074] The thickness of the silicon oxide layer 32b (fourth layer) is, for example, 10 nm or less, preferably 30 nm or less, more preferably 50 nm or less, and even more preferably 70 nm or less. In addition, it is, for example, 300 nm or more, preferably 200 nm or more, more preferably 150 nm or more, and even more preferably 120 nm or more.

[0075] The total thickness of the silicon oxide layer 32 is, for example, 20 nm or more, preferably 50 nm or more, more preferably 80 nm or more, and even more preferably 100 nm or more. In addition, it is, for example, 500 nm or less, preferably 300 nm or less, more preferably 200 nm or less, and even more preferably 150 nm or less.

[0076] In the case where the alternating laminate has a silicon oxide layer 32a (second layer) and a silicon oxide layer 32b (fourth layer), the thickness of the silicon oxide layer 32a (second layer) is preferably thinner than the thickness of the silicon oxide layer 32b (fourth layer).

[0077] The total thickness of the antireflective layer 3 (alternating laminate) is, for example, 50 nm or more, preferably 100 nm or more, more preferably 130 nm or more, and even more preferably 150 nm or more. In addition, it is, for example, 800 nm or less, preferably 500 nm or less, more preferably 300 nm or less, and even more preferably 200 nm or less.

[0078] If the total thickness of the antireflective layer 3 (alternating laminate) is above the lower limit mentioned above, the intensity of external light reflection can be suppressed. If the total thickness of the antireflective layer 3 (alternating laminate) is below the upper limit mentioned above, the cracking of the antireflective layer 3 can be suppressed.

[0079] The ratio of the thickness (total thickness) of the niobium oxide layer 31 to the total thickness of the alternating laminate is, for example, 1% or more, preferably 3% or more, more preferably 10% or more, even more preferably 15% or more, and especially preferably 20% or more. In addition, it is, for example, 80% or less, preferably 60% or less, more preferably 40% or less, even more preferably 35% or less, and especially preferably 30% or less.

[0080] The ratio of the thickness (total thickness) of the silicon oxide layer 32 to the total thickness of the alternating laminate is, for example, 20% or more, preferably 40% or more, more preferably 60% or more, further preferably 65% ​​or more, especially preferably 70% or more, and in addition, for example, 99% or less, preferably 97% or less, more preferably 90% or less, further preferably 85% or less, especially preferably 80% or less.

[0081] In other words, the thickness (total thickness) of the silicon oxide layer 32 is preferably thicker than the thickness (total thickness) of the niobium oxide layer 31.

[0082] The side of the antireflective layer 3 in the thickness direction (the side in contact with the antifouling layer 4) can be subjected to surface modification treatment. Examples of surface modification treatments include corona treatment, plasma treatment, ozone treatment, primer treatment, glow treatment, and coupling agent treatment.

[0083] The surface roughness Ra (arithmetic mean surface roughness) of the side of the antireflective layer 3 in the thickness direction (the side in contact with the antifouling layer 4) is, for example, 0.5 nm or more, preferably 0.8 nm or more, and furthermore, for example, 10 nm or less, preferably 8 nm or less.

[0084] It should be noted that the surface roughness Ra can be calculated, for example, from a 1 μm square observation image obtained using AFM (atomic force microscopy).

[0085] <Anti-fouling layer>

[0086] The antifouling layer 4 is a layer that prevents pollution from the external environment and makes it easy to remove attached pollutants. In addition, the antifouling layer 4 also has water vapor barrier properties. The antifouling layer 4 is the uppermost layer of the antireflective film 1.

[0087] The material for the antifouling layer 4 is not particularly limited, and for example, compounds having a siloxane skeleton as shown in the chemical formula -Si-O-Si- can be listed. That is, the antifouling layer 4 contains, for example, a compound having a siloxane skeleton, and is preferably formed from a compound having a siloxane skeleton. As such a compound having a siloxane skeleton, alkoxysilane compounds containing a dimethylsiloxane skeleton are preferably listed. As an alkoxysilane compound containing a dimethylsiloxane skeleton, for example, a compound shown in the following general formula (1) can be listed.

[0088] R1-X-(Si(CH3)2-O) n -Si(OR2)3 (1)

[0089] R1 can be exemplified by alkylsilyl groups, which are formed by replacing one or more hydrogen atoms of a hydrogen atom in a silyl group (SiH3-). Examples of alkylsilyl groups include trimethoxysilyl (Si(CH3)3-).

[0090] R2 can be, for example, alkyl groups having 1 or more but less than 4 carbon atoms. Methyl groups are preferred.

[0091] X is, for example, an ether group, a carbonyl group, an amino group, or an amide group. An ether group is preferred.

[0092] n is, for example, 1 to 50, preferably 10 to 40, and more preferably an integer of 20 to 30.

[0093] In other words, as alkoxysilane compounds containing a dimethylsiloxane skeleton, compounds represented by the following general formula (2) are preferably listed.

[0094] Si(CH3)3-O-(Si(CH3)2-O) m -Si(OCH3)3 (2)

[0095] m is, for example, 1 to 50, preferably 10 to 40, and more preferably an integer of 20 to 30.

[0096] Alkoxysilane compounds containing a dimethylsiloxane skeleton can be used alone or in combination with two or more.

[0097] If the material of the antifouling layer 4 contains an alkoxysilane compound with a dimethylsiloxane backbone, the antifouling function of the antifouling layer 4 can be improved.

[0098] As a material for the antifouling layer 4, an organofluorine compound having a terminal structure (terminal structure E) as shown in the chemical formula CF3OCF2- can also be listed. As such an organofluorine compound, an alkoxysilane compound having a perfluoropolyether backbone is preferred. As an alkoxysilane compound having a terminal structure E and a perfluoropolyether backbone, a compound of the following general formula (3) can be listed as an example.

[0099] CF3-OCF2-R3-Y-(CH2) r -Si(OR4)3 (3)

[0100] R3 represents a repeating structure containing at least one perfluoropolyether (PFPE) group, preferably a repeating structure containing two PFPE groups. R4 is, for example, an alkyl group with 1 or more but less than 4 carbon atoms, preferably methyl. Y is, for example, an ether group, carbonyl group, amino group or amide group, preferably an ether group. r is, for example, 1 to 20, preferably 1 to 10, more preferably an integer from 1 to 5.

[0101] The water contact angle (pure water contact angle) of the outer surface (exposed surface) of the antifouling layer 4 is, for example, 90° to 130°, preferably 95° to 130°, more preferably 98° to 130°, even more preferably 100° to 130°, and especially preferably 101° to 130°.

[0102] If the water contact angle of the outer surface of the antifouling layer 4 is above the lower limit value mentioned above, it has high antifouling properties.

[0103] It should be noted that the water contact angle is determined by forming water droplets (pure water droplets) with a diameter of less than 2 mm on the outer surface of the antifouling layer 4 and measuring the contact angle of the water droplets relative to the outer surface of the antifouling layer 4. The water contact angle of the outer surface of the antifouling layer 4 can be adjusted, for example, by adjusting the composition of the antifouling layer 4, the roughness of the outer surface, and the composition of other layers.

[0104] The thickness of the antifouling layer 4 is, for example, 0.5 nm or more, preferably 1.0 nm or more, more preferably 2.0 nm or more, and even more preferably 3.0 nm or more. In addition, it is, for example, 50 nm or less, preferably 30 nm or less, more preferably 10 nm or less, and even more preferably 8.0 nm or less.

[0105] Preferably, the difference in refractive index between the antifouling layer 4 and the layers in contact with it is small. Specifically, when the antifouling layer 4 is in contact with the silicon oxide layer 32, the refractive index of the antifouling layer 4 is, for example, 1.6 or less, more preferably 1.55 or less.

[0106] The thickness of the antireflective film 1 is, for example, 5 μm or more, preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, especially preferably 50 μm or more, and also, for example, 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, even more preferably 170 μm or less, especially preferably 150 μm or less.

[0107] The reflectivity of the antireflective film 1 is, for example, 0.0% or more, and furthermore, 8.0% or less, preferably 5.0% or less, more preferably 4.0% or less, even more preferably 2.0% or less, and especially preferably 1.0% or less.

[0108] It should be noted that the reflectance of the antireflective film 1 can be measured using a UV-Vis-IR spectrophotometer. More specifically, it can be measured using the methods described in the embodiments described later.

[0109] In the antireflection film 1, in the difference spectrum calculated according to the Fourier transform infrared spectrophotometer analysis (FT-IR analysis) described below, the 1050 cm⁻¹ －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value.－1 When the intensity of the absorption peak originating from the asymmetric stretching of Si-O-Si is set as X, 1 / X is, for example, 5.0 to 10.0, preferably 5.5 to 9.5, more preferably 6.0 to 9.0, further preferably 6.5 to 8.5, especially preferably 6.6 to 8.3, and most preferably 6.7 to 8.0.

[0110] In the antireflection film 1, in the difference spectrum calculated according to the Fourier transform infrared spectrophotometer analysis (FT-IR analysis) described below, the 1050 cm⁻¹ －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value. －1 When the absorption peak intensity derived from the asymmetric stretching of Si-O-Si is set as X, 1 / X is 5.0 or more, preferably 5.5 or more, more preferably 6.0 or more, even more preferably 6.5 or more, particularly preferably 6.6 or more, and most preferably 6.7 or more. In addition, for example, it is 10.0 or less, preferably 9.5 or less, more preferably 9.0 or less, even more preferably 8.5 or less, particularly preferably 8.3 or less, and most preferably 8.0 or less.

[0111] In the antireflection film 1, in the difference spectrum calculated according to the Fourier transform infrared spectrophotometer analysis (FT-IR analysis) described below, if 1050 cm⁻¹ －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value. －1 When the absorption peak intensity originating from the asymmetric stretching of Si-O-Si is set to X, and 1 / X is above the aforementioned lower limit, the proportion of structures with symmetric stretching of Si-O-Si becomes higher than that of structures with asymmetric stretching of Si-O-Si, thus resulting in excellent scratch resistance.

[0112] (FT-IR analysis)

[0113] Infrared absorption spectrum S1 was measured from the thickness direction of the antireflection film using the total internal reflection method of a Fourier transform infrared spectrophotometer. Infrared absorption spectrum S2 was measured from the thickness direction of the sample film obtained by removing the antireflection layer and antifouling layer from the antireflection film using the same method. Then, infrared absorption spectra S1 and S2 were analyzed using a 1730 cm⁻¹ infrared spectrophotometer. －1 The peaks originating from the C=O stretching vibrations of acrylates in the vicinity were normalized. The difference spectrum was calculated by subtracting the infrared absorption spectrum S2 from the normalized infrared absorption spectrum S1.

[0114] It should be noted that the infrared absorption spectrum S1 and infrared absorption spectrum S2 can be measured using a Fourier transform infrared spectrophotometer (FT-IR), and the specific measurement method is described in the examples described later.

[0115] Furthermore, although detailed in the embodiments described later, in the sample film obtained by removing the antifouling layer and the antireflective layer from the antireflective film, if the antireflective layer is completely removed, it is possible that even a portion of the transparent substrate film may be removed. If even a portion of the transparent substrate film is removed, then wavelengths exceeding 1000cm will be affected. －1 The region where Nb absorption affects the infrared absorption spectrum S2 is affected; therefore, the removal of the antireflective layer terminates at the niobium oxide layer closest to the transparent substrate film (specifically, the region where Nb was detected by elemental analysis). The infrared absorption of Nb is concentrated at 1000 cm⁻¹. －1 The following parameters were detected, therefore even if small amounts remain, they will not be detected at wavelengths exceeding 1000 cm⁻¹. －1 The region affects the infrared absorption spectrum S2.

[0116] Furthermore, even when the antireflective film includes a primer layer, its influence can be ignored since the difference between the infrared absorption spectrum S1 and the infrared absorption spectrum S2 is calculated.

[0117] In the antireflective film 1, the indentation modulus of 10 nm on one side of the thickness direction of the antifouling layer 4 is, for example, 16.0 GPa to 55.0 GPa, preferably 16.5 GPa to 50.0 GPa, more preferably 17.0 GPa to 48.0 GPa, even more preferably 17.5 GPa to 47.0 GPa, particularly preferably 18.0 GPa to 46.0 GPa, and most preferably 18.5 GPa to 45.0 GPa.

[0118] In the antireflective film 1, the indentation modulus of 10 nm on one side of the thickness direction of the antifouling layer 4 is, for example, 16.0 GPa or more, preferably 16.5 GPa or more, more preferably 17.0 GPa or more, even more preferably 17.5 GPa or more, particularly preferably 18.0 GPa or more, and most preferably 18.5 GPa or more. In addition, it is, for example, 55.0 GPa or less, preferably 50.0 GPa or less, more preferably 48.0 GPa or less, even more preferably 47.0 GPa or less, particularly preferably 46.0 GPa or less, and most preferably 45.0 GPa or less.

[0119] In the anti-reflective film 1, if the indentation modulus of elasticity of 10 nm on one side of the antifouling layer 4 in the thickness direction is above the aforementioned lower limit, then the scratch resistance during sliding of steel wool or the like is excellent. Furthermore, in the anti-reflective film 1, if the indentation modulus of elasticity of 10 nm on one side of the antifouling layer 4 in the thickness direction is below the aforementioned upper limit, then the generation of cracks or the like can be suppressed.

[0120] It should be noted that, in the antireflective film 1, the indentation modulus of elasticity at 10 nm on one side of the thickness direction of the antifouling layer 4 refers to the elastic modulus when the indentation depth is set to 10 nm. More specifically, it can be measured using the method described in the embodiments below.

[0121] 2. Manufacturing method of anti-reflective film

[0122] Reference Figure 2 2A~ Figure 2 Section 2E describes the manufacturing method of the antireflective film of the present invention.

[0123] The manufacturing method of the antireflective film 1 includes, for example, a preparation step of preparing a transparent resin film 21. Figure 2 2A); the process of forming a cured resin layer 22 on a transparent resin film 21 ( Figure 2 2B); the primer layer forming process of forming primer layer 5 on cured resin layer 22 ( Figure 2 2C); the antireflective layer formation process of forming an alternating laminate of niobium oxide layer 31 and silicon oxide layer 32 on primer layer 5 ( Figure 2 2D); and the antifouling layer forming process of forming an antifouling layer 4 on the antireflective layer 3 ( Figure 2 (2E). It should be noted that the primer layer formation process and the anti-reflective layer formation process use, as in... Figure 3 The sputtering film formation apparatus Z shown is used sequentially.

[0124] <Preparation Process>

[0125] In the preparation process, such as Figure 2 As shown in 2A, a transparent resin film 21 is prepared.

[0126] <Curing Resin Layer Formation Process>

[0127] In the process of forming the cured resin layer, such as Figure 2 As shown in 2B, a cured resin layer 22 is formed on one side of the transparent resin film 21 in the thickness direction. Specifically, after the above-mentioned curable resin composition is coated on one side of the transparent resin film 21 to form a coating film, the coating film is cured to form the cured resin layer 22.

[0128] When the curable resin composition contains a solvent, the coating on the transparent resin film 21 is dried after the curable resin composition is applied.

[0129] The drying temperature is, for example, 50°C to 120°C. The drying time is, for example, 10 seconds to 10 minutes.

[0130] When the curable resin composition includes a UV-curable resin, the coating on the transparent resin film 21 is cured by UV irradiation. Examples of UV irradiation sources include high-pressure mercury lamps and LED lamps. The cumulative UV irradiation intensity is, for example, 100 mJ / cm². 2 ~500mJ / cm 2 .

[0131] As described above, a transparent substrate film 2 is obtained having a cured resin layer 22 on one side of the transparent resin film 21 in the thickness direction. In this embodiment, a roll of the transparent substrate film 2 is prepared. Specifically, the transparent substrate film 2 is wound with the side of the cured resin layer 22 facing radially inward of the roll.

[0132] [Sputtering film formation apparatus Z]

[0133] In the manufacturing method of the antireflective film 1, the primer layer formation process and the antireflective layer formation process are performed sequentially while the transparent substrate film 2 is conveyed as the working film W in a roll-to-roll manner under reduced pressure. (Refer to...) Figure 3 and Figure 4 A magnetron sputtering film forming apparatus Z will be described as an example of an apparatus for performing a primer layer forming process and an anti-reflective layer forming process.

[0134] like Figure 3 As shown, the sputtering film forming apparatus Z includes a conveying section P1 and a film forming section P2.

[0135] The conveying unit P1 includes a conveying housing 51, a feed roller 52, a take-up roller 53, a guide roller 54, and a vacuum pump 55.

[0136] The conveyor housing 51 has a generally box-shaped form extending along the conveying direction. The conveyor housing 51 houses the feed roller 52, the take-up roller 53, and the guide roller 54.

[0137] The feed roller 52 and the take-up roller 53 are respectively disposed at the upstream and downstream ends of the conveying direction within the conveying housing 51. A roll of the transparent substrate film 2 is mounted on the feed roller 52 in the form of a working film W. Furthermore, the take-up roller 53 is a roller used to take up the working film W. Multiple guide rollers 54 are disposed between the feed roller 52 and the take-up roller 53. The multiple guide rollers 54 are arranged such that the transparent substrate film 2 is wound onto the film-forming roller 63.

[0138] Vacuum pump 55 is located in delivery housing 51.

[0139] The film-forming section P2 includes a film-forming housing 61, a film-forming roller 63, and multiple magnetron plasma units 64.

[0140] The film-forming housing 61 is continuous with the transport housing 51, and together they form a vacuum chamber. The film-forming housing 61 has a generally box-shaped shape. The film-forming housing 61 has multiple partition walls 62. The multiple partition walls 62 extend toward the film-forming roller 63. It should be noted that a sputtering gas supply device (not shown) is provided in the film-forming housing 61. The film-forming housing 61 houses the film-forming roller 63 and multiple magnetron plasma units 64.

[0141] The axis of the film-forming roller 63 is along the width direction, which is orthogonal to the conveying direction and thickness direction of the transparent substrate film 2.

[0142] Multiple magnetron plasma units 64 are arranged opposite each other on the radially outer side of the film-forming roller 63. The multiple magnetron plasma units 64 are arranged in a manner that is spaced apart from each other along the circumference of the film-forming roller 63.

[0143] Adjacent magnetron plasma units 64 in the circumferential direction are separated by partition walls 62. The spaces separated by partition walls 62 constitute film-forming chambers R. Film-forming chambers R are divided into multiple units (e.g., first film-forming chamber R1, second film-forming chamber R2, third film-forming chamber R3, fourth film-forming chamber R4) within the film-forming housing 61 (vacuum chamber). One magnetron plasma unit 64 is provided in each film-forming chamber R. Figure 4 As shown, each of the multiple magnetron plasma units 64 has a plasma housing 71, a first unit 72, and a second unit 73.

[0144] The plasma housing 71 has a generally box-shaped shape with one side open towards the film-forming roller 63. The plasma housing 71 extends along the axis of the film-forming roller 63. The plasma housing 71 houses a first unit 72 and a second unit 73. The first unit 72 and the second unit 73 are arranged adjacent to each other in a manner that is spaced apart from each other along the circumference of the film-forming roller 63. The first unit 72 and the second unit 73 face the film-forming roller 63 through the opening of the plasma housing 71.

[0145] The first unit 72 and the second unit 73 have the same structure except for the rotation direction of the rotating target 74 (described later). Therefore, the first unit 72 will be described in detail, and the second unit 73 will be described briefly. It should be noted that... Figure 5 This refers to the magnet unit 75 of the first magnetron plasma unit 64 used to form the primer layer 5. Figure 6 This refers to the magnet unit 75 of the second magnetron plasma unit 64 used to form the antireflective layer 3.

[0146] like Figure 4 As shown, the first unit 72 includes a rotating target 74 and a magnet unit 75.

[0147] The rotating target 74 has a cylindrical shape and an axis AL (center in cross-sectional view, reference) parallel to the axis of the film-forming roller 63. Figure 5 and Figure 6 The rotating target 74 is capable of rotating (or circumferentially moving) in the opposite direction to the rotation of the film-forming roller 63. The rotating target 74 is electrically connected to a cathode source (not shown), thereby functioning as a cathode. Furthermore, a target material is laminated on the outer peripheral surface of the rotating target 74. Examples of target materials include the material of the primer layer 5 described above, niobium, or low-valent niobium oxide (NbO). X X < 2.5 (material of niobium oxide layer 31) and silicon (material of silicon oxide layer 32).

[0148] The magnet unit 75 is housed radially inside the rotating target 74. For example... Figure 5 and Figure 6 As shown, the magnet unit 75 includes a fixing member 80, two first magnets 81 and two second magnets 82.

[0149] The fixing member 80 has a narrow plate shape extending along the axial direction of the film-forming roller 63, and is called a magnetic yoke. One side of the fixing member 80 in the thickness direction (the main surface 83 of one side) and the other side in the thickness direction (the main surface of the other side) are both flat surfaces. The main surface 83 of one side is opposite to the film-forming roller 63. The main surface of the other side is parallel to the main surface 83 of the first side. Examples of materials for the fixing member 80 include metals such as iron.

[0150] Each of the two first magnets 81 and the two second magnets 82 has a quadrangular prism shape extending along the axial direction of the film-forming roller 63. The two first magnets 81 and the two second magnets 82 are fixed to one of the main surfaces 83 of the fixing member 80. The two first magnets 81 and the two second magnets 82 are arranged adjacent to each other in the width direction of the fixing member 80. Specifically, the two first magnets 81 and the two second magnets 82 are in contact with each other in the width direction.

[0151] The two first magnets 81 and the two second magnets 82, when viewed in cross-section along the width and thickness directions of the fixed member 80 (corresponding to directions orthogonal to the axis of the rotating target 74), include a first magnetic pole portion 91, a second magnetic pole portion 92, a third magnetic pole portion 93, and a fourth magnetic pole portion 94.

[0152] The first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 are arranged sequentially along one circumferential direction (the rotation direction of the rotating target 74). The first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 are arranged sequentially in contact with each other on one side of the width direction of the fixing member 80.

[0153] The second magnetic pole section 92 and the third magnetic pole section 93 are each composed of two first magnets 81. These second magnetic pole sections 92 and the third magnetic pole section 93, for example, have an N pole. The first magnetic pole section 91 and the fourth magnetic pole section 94 are each composed of a second magnet 82. The first magnetic pole section 91 and the fourth magnetic pole section 94 have an S pole.

[0154] In cross-sectional view, the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 each have a generally rectangular shape with the same shape. In cross-sectional view, each of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 has a generally rectangular shape, which includes: a fixed side 95, fixed to one of the main surfaces 83 of the fixing member 80; an opposite side 96, located on the side opposite to the fixed side 95; and two side edges 97, connecting the two end edges of the fixed side 95 and the opposite side 96.

[0155] The fixed edges 95 of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 are disposed on one of the main surfaces 83 of the fixing member 80. The opposite edges 96 of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 are parallel to one of the main surfaces 83 of the fixing member 80. The opposite edges 96 of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93, and the fourth magnetic pole portion 94 are continuous along the width direction, specifically on the same plane (forming a flat surface).

[0156] The thickness and width lengths of the first magnetic pole section 91, the second magnetic pole section 92, the third magnetic pole section 93, and the fourth magnetic pole section 94 are different depending on the sputtering angle to be set.

[0157] exist Figure 5 In the magnet unit 75 of the first magnetized plasma unit 64 shown in the figure, the length in the thickness direction and the length in the width direction of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93 and the fourth magnetic pole portion 94, that is, the ratio (D / L) of the separation distance D between the opposite side 96 and the fixed side 95 to the length L of the opposite side 96, are, for example, 0.8 to 1.2, preferably 0.9 to 1.1, and more preferably 1.0.

[0158] exist Figure 5In the magnet unit 75 of the first magnetron plasma unit 64 shown in the figure, the thickness length and width length of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93 and the fourth magnetic pole portion 94 are preferably equal.

[0159] If the ratio (D / L) is within the range described above, then the sputtering angle (angle θ) is as shown below.

[0160] exist Figure 5 In the magnet unit 75 of the first magnetron plasma unit 64 shown in the diagram, under cross-sectional view, the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 are along the thickness direction of the fixing member 80 (parallel to the thickness direction of the fixing member 80) (orthogonal to the width direction of the fixing member 80). Furthermore, the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 are along the width direction of the fixing member 80 (parallel to the width direction of the fixing member 80) (orthogonal to the thickness direction of the fixing member 80). If the magnetization directions are as described above, the sputtering angle (angle θ) is as shown below.

[0161] As Figure 5 The sputtering angle (angle θ) in the magnet unit 75 of the first magnetron plasma unit 64 shown is, for example, 35 degrees to 50 degrees, preferably 37 degrees to 48 degrees, more preferably 39 degrees to 46 degrees, and even more preferably 40 degrees to 45 degrees.

[0162] As Figure 5 The sputtering angle (angle θ) in the magnet unit 75 of the first magnetron plasma unit 64 shown is, for example, 35 degrees or more, preferably 37 degrees or more, more preferably 39 degrees or more, and even more preferably 40 degrees or more. In addition, it is, for example, 50 degrees or less, preferably 48 degrees or less, more preferably 46 degrees or less, and even more preferably 45 degrees or less.

[0163] It should be noted that the sputtering angle refers to the angle θ shown below. On the outer circumferential surface of the rotating target 74, the tangential component of the magnetic flux density is measured in a direction circumferential towards the rotating target. The angle θ between line segments LS1 and LS2 is determined, where LS1 is the line segment connecting the point MAX_P, corresponding to the largest tangential component of the magnetic flux density, to the center of the rotating target 74, and LS2 is the line segment connecting the point MIN_P, corresponding to the smallest tangential component of the magnetic flux density, to the center. The angle θ is obtained, for example, through magnetic field simulation using commercially available software.

[0164] Here, the tangential component of the magnetic flux density obtained through the above simulation will be explained.

[0165] like Figure 5 and Figure 6 As shown, in the first unit 72, a tunnel-shaped first magnetic field MF1 (depicted by multiple points) is generated from the opposite side of the second magnetic pole section 92 with the N pole toward the opposite side of the first magnetic pole section 91 with the S pole. It should be noted that if the second magnetic pole section 92 is the N pole and the first magnetic pole section 91 is the S pole, then by measuring the tangential component of the magnetic flux density in the circumferential direction of the rotating target 74 and in a direction from the first magnetic pole section 91 toward the second magnetic pole section 92, the minimum magnetic flux density (that is, the strongest value of the magnetic field on the negative side, MIN_P) can be obtained.

[0166] Furthermore, a second magnetic field MF2 (described by multiple points) in the shape of a tunnel is generated from the opposite side of the third magnetic pole section 93 with the N pole toward the opposite side of the fourth magnetic pole section 94 with the S pole. If the third magnetic pole section 93 is the N pole and the fourth magnetic pole section 94 is the S pole, the maximum magnetic flux density (that is, the strongest value of the magnetic field on the positive side, MAX_P) can be obtained by measuring the tangential component of the magnetic flux density in the circumferential direction of the rotating target 74 and in a direction from the third magnetic pole section 93 toward the fourth magnetic pole section 94.

[0167] It should be noted that the points MAX_P and MIN_P, which correspond to the largest and smallest tangential components of the magnetic flux density, have the same meaning as the two maxima in the absolute value of the tangential components of the magnetic flux density.

[0168] The sputtering angle (angle θ) is the angle on the side of the film-forming roller 63 formed by the two line segments LS1 and LS2 mentioned above.

[0169] At once Figure 5 Regarding the sputtering angle of the magnet unit 75 in the first magnetized plasma unit 64 shown in the figure, the distance in the circumferential direction between the plasma corresponding to the largest tangential component of the magnetic flux density and the plasma corresponding to the smallest tangential component of the magnetic flux density becomes greater on the radially outer side of the rotating target 74.

[0170] On the other hand, Figure 6 The thickness direction length and width direction length of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93 and the fourth magnetic pole portion 94 in the magnet unit 75 of the second magnetized plasma unit 64 shown in the figure, that is, the ratio (D / L) of the separation distance D between the opposite side 96 and the fixed side 95 to the length L of the opposite side 96, is, for example, 1.2 to 6.0, preferably 1.3 to 6.0, more preferably 1.5 to 6.0, further preferably 1.6 to 6.0, and especially preferably 1.7 to 6.0.

[0171] exist Figure 6The thickness direction length and width direction length of the first magnetic pole portion 91, the second magnetic pole portion 92, the third magnetic pole portion 93 and the fourth magnetic pole portion 94 in the magnet unit 75 of the second magnetized plasma unit 64 shown in the figure, that is, the ratio (D / L) of the separation distance D (length of the side side) between the opposite side and the fixed side to the length L of the opposite side, is, for example, 1.2 or more, preferably 1.3 or more, more preferably 1.5 or more, further preferably 1.6 or more, especially preferably 1.7 or more, and in addition, for example, 6.0 or less.

[0172] If the ratio (D / L) is within the range described above, then the sputtering angle (angle θ) is as shown below.

[0173] exist Figure 6 In the magnet unit 75 of the second magnetron plasma unit 64 shown in the diagram, under cross-sectional observation, the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 are inclined relative to the thickness and width directions of the fixing member 80, while the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 are along the width direction of the fixing member 80 (parallel to the width direction of the fixing member 80) (orthogonal to the thickness direction of the fixing member 80). It should be noted that the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 may also be inclined relative to the thickness and width directions of the fixing member 80.

[0174] Specifically, the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 respectively tilt toward intersecting directions as they approach the film-forming roller 63 in the thickness direction of the fixing member 80.

[0175] It should be noted that when the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 are also inclined relative to the thickness direction and the width direction of the fixing member 80, the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 respectively incline towards each other as they move away from the film forming roller 63 in the thickness direction of the fixing member 80.

[0176] By aligning the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 with mutually intersecting directions, the magnetic flux on the surface of the rotating target 74 can be concentrated. Consequently, the two magnetic fields in the tunnel shape are brought close together, resulting in a sputtering angle (angle θ) as shown below. Specifically, Figure 6 The sputtering angle (angle θ) in the magnet unit 75 of the second magnetron plasma unit 64 shown in the figure is greater than that of the magnet unit 75. Figure 5 The sputtering angle (angle θ) in the magnet unit 75 of the first magnetron plasma unit 64 shown in the figure is small.

[0177] As Figure 6The sputtering angle (angle θ) in the magnet unit 75 of the second magnetron plasma unit 64 shown in the figure is, for example, 10 degrees to 35 degrees, preferably 15 degrees to 34 degrees, more preferably 20 degrees to 33 degrees, and even more preferably 22 degrees to 32 degrees.

[0178] As Figure 6 The sputtering angle (angle θ) in the magnet unit 75 of the second magnetron plasma unit 64 shown in the figure is, for example, 10 degrees or more, preferably 15 degrees or more, more preferably 20 degrees or more, and even more preferably 22 degrees or more. In addition, it is, for example, 35 degrees or less, preferably 34 degrees or less, more preferably 33 degrees or less, and even more preferably 32 degrees or less.

[0179] Furthermore, if the sputtering angle (angle θ) is within the aforementioned range, the circumferential distance between the plasma corresponding to the largest tangential component of the magnetic flux density and the plasma corresponding to the smallest tangential component of the magnetic flux density on the radially outer side of the rotating target 74 becomes closer. Therefore, the region with a high density of electrons released from the rotating target 74 can be concentrated. In other words, the maximum magnetic flux density at point MAX_P can be increased. As a result, in the silicon oxide layer 32 closest to the antifouling layer 4, the proportion of structures with Si-O-Si symmetrical stretching can be increased relative to structures with Si-O-Si asymmetric stretching, thereby enabling the fabrication of an antireflective film with excellent scratch resistance. Furthermore, if the sputtering angle (angle θ) is above the aforementioned lower limit, the magnetic flux density can be prevented from becoming too low. In other words, the minimum magnetic flux density at point MIN_P can be made smaller, allowing for continuous plasma generation.

[0180] Materials used for the first magnet 81 and the second magnet 82 include, for example, permanent magnets such as neodymium magnets.

[0181] like Figure 4 As shown, the second unit 73 includes: a rotating target 74, which can rotate in the same direction as the rotation of the film forming roller 63; and the aforementioned magnet unit 75.

[0182] The second unit 73 also has the same structure as the first unit 72.

[0183] <Primer Layer Formation Process>

[0184] In the process of forming the primer layer 5, specifically, the material of the primer layer 5 is formed by sputtering on one side of the transparent substrate film 2 in the thickness direction (the side of the cured resin layer 22 in the thickness direction), thus forming the primer layer 5. In other words, the primer layer 5 is a sputtered layer.

[0185] In the sputtering method, a sputtering film forming apparatus Z, as described above, capable of performing film forming in a roll-to-roll manner, is used. In the primer layer formation process, when using a roll-to-roll sputtering film forming apparatus, the transparent substrate film 2, serving as the working film W, is moved from the feed roller of the apparatus to the take-up roller, and the primer layer 5 material is formed on the thickness-direction side of the transparent substrate film 2, thus forming the primer layer 5. The travel speed of the working film W (transparent substrate film 2) is, for example, 0.5 to 10.0 m / min. It should be noted that in the primer layer formation process, using... Figure 5 The first magnetized plasma unit 64 shown in the figure has a magnet unit 75.

[0186] It should be noted that in the sputtering method of the primer layer formation process, a sputtering film forming apparatus with a film forming chamber can be used, or an apparatus such as... Figure 3 The sputtering film forming apparatus shown has multiple film forming chambers (R1 to R4) arranged sequentially along the travel path of the working film W (transparent substrate film 2).

[0187] In the sputtering method, specifically, a sputtering gas (inert gas) is introduced into the film-forming chamber R under vacuum conditions, and a negative voltage is applied to a target arranged on the outer peripheral surface of a rotating target 74 within the film-forming chamber R. This generates a glow discharge, ionizing the gas atoms. These gas ions collide at high speed with the target surface, ejecting target material from the target surface. The ejected target material is then deposited on one side of the working film W (transparent substrate film 2) in the thickness direction. The target material is, for example, a sintered body of the material described above for the primer layer 5.

[0188] Examples of sputtering gases include argon, krypton, xenon, and mixtures thereof, with argon being the most preferred. The sputtering method is preferably reactive sputtering. In reactive sputtering, for example, oxygen, as a reactive gas, is introduced into the film-forming chamber in addition to the sputtering gas. That is, the primer layer 5 is formed in the presence of an inert gas and oxygen.

[0189] The ultimate vacuum in the film-forming chamber before sputtering is, for example, 1.5 × 10⁻⁶. －4 Below Pa.

[0190] In reactive sputtering, the volume of oxygen introduced into the film-forming chamber is, for example, 1% to 30% of the total volume of sputtering gas and oxygen (reactive gas), preferably 3% to 20% of the total volume, more preferably 5% to 15% of the total volume, and even more preferably 7% to 12% of the total volume.

[0191] The film-forming temperature (the temperature of the transparent substrate film 2 when the primer layer 5 is formed) is, for example, -50.0℃ to 30.0℃, preferably -30.0℃ to 20.0℃, more preferably -20.0℃ to 10.0℃, and even more preferably -15.0℃ to 0.0℃.

[0192] The pressure in the film-forming chamber (the pressure in the film-forming chamber when sputtering gas and oxygen are introduced) is, for example, 0.01 Pa to 5.0 Pa, preferably 0.05 Pa to 1.0 Pa, more preferably 0.10 Pa to 0.50 Pa, and even more preferably 0.15 Pa to 0.30 Pa.

[0193] Examples of power sources for applying voltage to a target include: DC (Direct Current) power supplies, AC (Alternating Current) power supplies, MF (Middle Frequency) power supplies, and RF (Radio Frequency) power supplies. MF and AC power supplies can also be used together. An MFAC power supply is preferably used.

[0194] The horizontal magnetic field strength on the target is, for example, 10mT to 100mT.

[0195] As described above, a primer layer 5 is formed on one side of the transparent substrate film 2 in the thickness direction.

[0196] <Anti-reflective layer formation process>

[0197] In the antireflective layer formation process, specifically, an alternating laminate of niobium oxide layer 31 and silicon oxide layer 32 is formed on one side of the primer layer 5 in the thickness direction by sputtering. That is, the niobium oxide layer 31 and silicon oxide layer 32 are sputtered layers.

[0198] In the sputtering method, a sputtering film forming apparatus Z, as described above, is used, capable of performing film forming in a roll-to-roll manner. In the antireflective layer formation process, when using a roll-to-roll sputtering film forming apparatus, a transparent substrate film 2 having a primer layer 5, serving as the working film W, is fed from a feed roller to a take-up roller, and alternating laminate materials (specifically, niobium and silicon) are sequentially formed on the thickness direction side of the primer layer 5 to form an alternating laminate. The travel speed of the working film W (the transparent substrate film 2 having the primer layer 5) is, for example, 0.5 to 10.0 m / min. It should be noted that in the antireflective layer formation process, using... Figure 6 The second magnetron plasma unit 64 shown in the figure has a magnet unit 75. That is, the antireflection layer 3 is formed by sputtering at a sputtering angle of 35 degrees or less. More specifically, the niobium oxide layer 31 and the silicon oxide layer 32 are formed by sputtering at a sputtering angle of 35 degrees or less.

[0199] By using a sputtering method with a sputtering angle of 35 degrees or less, the silicon oxide layer 32, which is closest to the antifouling layer 4 in the antireflective layer 3, is formed into a film. This allows for a higher proportion of structures with symmetrical Si-O-Si stretching compared to structures with Si-O-Si asymmetric stretching. Specifically, the result is the manufacture of an antireflective film with excellent scratch resistance.

[0200] It should be noted that in the sputtering method of the antireflective layer formation process, methods such as... Figure 3 A sputtering film forming apparatus, as shown, having multiple film forming chambers (R1 to R4) arranged sequentially along the travel path of the working film W (a transparent substrate film 2 having a primer layer 5), forms the first to fourth layers sequentially.

[0201] In sputtering, specifically, a sputtering gas (inert gas) is introduced into the film-forming chamber of a sputtering film-forming apparatus under vacuum conditions, and a negative voltage is applied to a target positioned on the outer peripheral surface of a rotating target within the film-forming chamber. This generates a glow discharge, ionizing the gas atoms. These gas ions collide at high speed with the target surface, ejecting target material from the target surface, which is then deposited sequentially along the thickness direction. Niobium or low-valence niobium oxide (NbO) is used as the target material in the first and third layers. X (X < 2.5), silicon is used in the second and fourth layers.

[0202] Examples of sputtering gases include argon, krypton, xenon, and mixtures thereof, with argon being a preferred example.

[0203] In the formation of the antireflective layer 3, the sputtering method is preferably reactive sputtering. In reactive sputtering, for example, oxygen, as a reactive gas, is introduced into the film-forming chamber in addition to the sputtering gas. That is, the antireflective layer 3 is formed in the presence of an inert gas and oxygen.

[0204] Specifically, when forming the first and third layers using reactive sputtering, the volume of oxygen introduced into the film-forming chamber is, for example, 0.5% to 20% of the total volume of sputtering gas and oxygen (reactive gas), preferably 1% to 10% of the total volume, more preferably 2% to 8% of the total volume, and even more preferably 3% to 6% of the total volume.

[0205] Furthermore, when forming the second and fourth layers using reactive sputtering, impedance control or PEM (plasma emission monitoring and control) is used to control the amount of oxygen introduced, so that a film can be formed in the transition region between the metal region and the oxide region. That is, the silicon oxide layer 32, the layer closest to the antifouling layer, is formed by reactive sputtering. In the formation of the silicon oxide layer 32, the layer closest to the antifouling layer, using reactive sputtering, oxygen is introduced using impedance control or PEM to form a film in the transition region between the metal region and the oxide region.

[0206] It should be noted that in reactive sputtering, during film formation, the proportion of reactive gases in all introduced gases (sputtering gas and reactive gas) can roughly distinguish the metal region, transition region, oxide region, and film formation state. In the metal region, the proportion of oxygen (reactive gas) is low, and even slight changes in the oxygen proportion result in a constant film formation rate. Similarly, in the oxide region, the proportion of oxygen is high, and even slight changes in the oxygen proportion also result in a constant film formation rate. On the other hand, in the transition region, the oxygen proportion is intermediate between the metal and oxide regions, and the film formation rate varies significantly with slight changes in the oxygen proportion. In other words, a stable film formation rate is possible in the metal and oxide regions, but in the transition region, the film formation rate fluctuates with slight changes in the oxygen proportion. Therefore, to form a film in the transition region, it is necessary to control the amount of oxygen introduced.

[0207] Methods for controlling the amount of oxygen introduced in a way that creates a transition region include, for example, impedance control, which controls the amount of oxygen introduced in such a way that the plasma impedance is constant, i.e., the discharge voltage is constant; and PEM control, which controls the amount of oxygen introduced into the film-forming chamber by sensing the intensity of the discharged plasma.

[0208] If the oxygen content is controlled in a way that creates a transition region, the second and fourth layers can be deposited at a high voltage, and the film formation rate can be increased. As a result, for the silicon oxide layer 32, which is closest to the antifouling layer 4 in the antireflective layer 3, the proportion of the structure with Si-O-Si symmetric stretching can be increased relative to the structure with Si-O-Si asymmetric stretching.

[0209] The pressure in the film-forming chamber (the pressure in the film-forming chamber when sputtering gas and / or 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.

[0210] It should be noted that the ultimate vacuum degree in the film-forming chamber before sputtering, the film-forming temperature (the temperature of the transparent substrate film 2 when forming each layer), the power supply for applying voltage to the target, and the horizontal magnetic field strength on the target are the same as those in the primer layer formation process described above.

[0211] As described above, an anti-reflective layer 3 is formed on one side of the primer layer 5 in the thickness direction.

[0212] <Antifouling layer formation process>

[0213] In the antifouling layer formation process, specifically, the antifouling layer 4 is formed on one side of the antireflective layer 3 in the thickness direction by a dry coating method. Examples of dry coating methods include vacuum evaporation, sputtering, and CVD (Chemical Vapor Deposition), with vacuum evaporation being preferred. That is, the antifouling layer 4 is preferably an evaporated film (layer).

[0214] In the vacuum evaporation method, the material of the above-mentioned antifouling layer 4 is dried, and the solidified material is used as the evaporation source.

[0215] The vapor deposition temperature is, for example, 150°C to 500°C, preferably 200°C to 300°C.

[0216] Thus, an antifouling layer 4 is formed on one side of the anti-reflective layer 3 in the thickness direction.

[0217] As described above, manufacture an anti-reflective film.

[0218] (Effects)

[0219] Regarding the antireflective film 1 mentioned above, in the difference spectrum calculated based on Fourier transform infrared spectrophotometry (FT-IR analysis), the 1050 cm⁻¹... －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value. －1 When the intensity of the absorption peak originating from the asymmetric stretching of Si-O-Si is set as X, 1 / X is greater than 3.5.

[0220] Therefore, compared to structures with Si-O-Si asymmetric stretching, the proportion of structures with Si-O-Si symmetric stretching is higher, resulting in superior scratch resistance.

[0221] Regarding the manufacturing method of the antireflective film 1 described above, the silicon oxide layer 32, which is the layer closest to the antifouling layer 4 in the antireflective layer 3, is formed by sputtering at a sputtering angle of 35 degrees or less. Therefore, an antireflective film 1 with excellent scratch resistance can be manufactured.

[0222] 3. Variations

[0223] <Examples of variations of antireflective coatings>

[0224] exist Figure 1 In this process, the antireflective layer 3 is an alternating stack of niobium oxide layer 31a, silicon oxide layer 32a, niobium oxide layer 31b and silicon oxide layer 32b, but is not limited to this.

[0225] In other words, there are no particular limitations as long as the antireflective layer 3 is an alternating laminate formed by at least one niobium oxide layer 31 and at least one silicon oxide layer 32, and the layer in the antireflective layer 3 closest to the antifouling layer 4 is the silicon oxide layer 32. Specifically, there are no particular limitations on the number of layers and the stacking order of the antireflective layer 3.

[0226] That is, the anti-reflective layer 3 can be, for example, an alternating laminate formed by a niobium oxide layer 31 and a silicon oxide layer 32, or an alternating laminate formed by three or more niobium oxide layers 31 and three or more silicon oxide layers 32.

[0227] <Manufacturing Method of Modified Examples of Antireflective Film>

[0228] exist Figure 2 2A~ Figure 2 In the manufacturing method of the antireflective film 1 shown in 2E, a primer layer 5 is formed, but it is not limited to this.

[0229] In other words, there are no particular limitations in the manufacturing method of the antireflective film 1, as long as the antireflective layer 3 is formed on one side of the thickness direction of the transparent substrate film 2 by sputtering. Specifically, the primer layer formation process may also be omitted.

[0230] In addition, Figure 2 2A~ Figure 2 In the manufacturing method of the antireflective film 1 shown in 2E, in the antireflective layer forming process, a method is used... Figure 6 The second magnetized plasma unit 64 shown in the figure has a magnet unit 75 that forms all the layers of niobium oxide layer 31a, silicon oxide layer 32a, niobium oxide layer 31b and silicon oxide layer 32b, but is not limited thereto.

[0231] In other words, in the anti-reflective layer formation process, as long as the following is used Figure 6 The magnet unit 75 of the second magnetron plasma unit 64 shown is formed on the silicon oxide layer 32, which is the layer closest to the antifouling layer 4 in the antireflective layer 3, and there is no particular limitation thereto.

[0232] More specifically, in the above-described method for manufacturing the antireflective film 1, the silicon oxide layer 32, other than the niobium oxide layer 31 of the antireflective layer 3 and the silicon oxide layer 32 closest to the antifouling layer 4, can be... Figure 5The first magnetized plasma unit 64 shown in the figure is formed by the magnet unit 75.

[0233] Example

[0234] The following examples, comparative examples, and reference examples are provided to further illustrate the present invention. It should be noted that the present invention is not limited to any particular example, comparative example, or reference example. Furthermore, the specific numerical values ​​of proportions (including proportions), physical property values, parameters, etc., used in the following description can be replaced by the corresponding upper limits (defined as "below" or "less than") or lower limits (defined as "above" or "exceeding") of the proportions (including proportions), physical property values, parameters, etc., described in the "Specific Embodiments" above.

[0235] Example 1

[0236] <Production of Anti-reflective Film>

[0237] The anti-reflective film is fabricated as shown below.

[0238] [Fabrication of transparent substrate film]

[0239] A curable resin layer forming composition with a solid content of 42% by mass was prepared by mixing 83 parts by mass of an acrylic monomer composition containing nano-silica particles (trade name: NC035HS, solid content concentration: 60% by mass, manufactured by Arakawa Chemical Industry Co., Ltd.), 17 parts by mass of a UV-curable polyfunctional urethane acrylate (trade name: BEAMSET 580, solid content concentration: 70% by mass, manufactured by Arakawa Chemical Industry Co., Ltd.), 1.5 parts by mass of a photopolymerization initiator (trade name: OMNIRAD127D, manufactured by IGM Resins), 0.15 parts by mass of a leveling agent (trade name: LE303, solid content concentration: 40% by mass, manufactured by Kyoeisha Chemical Co., Ltd.), and butyl acetate. This curable resin layer forming composition was then applied to one side of an 80 μm thick cellulose triacetate film (trade name: FUJITAC, manufactured by FUJI FILM) with a dried thickness of 5 μm, and dried at 80°C for 3 minutes. Then, a high-pressure mercury lamp was used to irradiate the area with a cumulative light intensity of 200 mJ / cm². 2 The ultraviolet light causes the coating layer to cure, forming a cured resin layer. Thus, a transparent substrate film with a cured resin layer on a transparent resin film is obtained.

[0240] [Formation of the primer layer]

[0241] First, plasma treatment is performed on one side of the transparent substrate film in the thickness direction (the side in the thickness direction of the cured resin layer). The plasma treatment uses methods such as... Figure 3The image shows a roll-to-roll sputtering film deposition apparatus Z (magnetron sputtering film deposition apparatus Z). It should be noted that the sputtering film deposition apparatus Z includes a film deposition chamber capable of moving the working film (transparent substrate film) in a roll-to-roll manner and performing the film deposition process. Vacuum degassing is performed until the ultimate vacuum level within the film deposition chamber of the sputtering film deposition apparatus reaches 1.0 × 10⁻⁶. －4 After Pa, argon gas, which is used as a sputtering gas (inert gas), is introduced into the film-forming chamber. The gas pressure in the film-forming chamber is set to 0.5 Pa, and the discharge power is set to 0.15 kW. While conveying the transparent substrate film, plasma treatment is performed on one side of the thickness direction of the cured resin layer.

[0242] Next, an ITO layer (primer layer) with a thickness of 4 nm is formed on one side of the transparent substrate film (the side of the cured resin layer) in the thickness direction using reactive sputtering. The primer layer is formed using... Figure 3 The sputtering film deposition apparatus Z shown is a roll-to-roll sputtering film deposition apparatus (magnetron sputtering film deposition apparatus Z). It should be noted that the sputtering film deposition apparatus Z includes a film deposition chamber capable of moving the working film (transparent substrate film) in a roll-to-roll manner and performing the film deposition process. Furthermore, the sputtering film deposition apparatus Z includes... Figure 5 The first magnetron plasma unit 64 shown in the figure has a magnet unit 75. Details of the magnet unit and sputtering film formation conditions for forming the primer layer are shown below.

[0243] In the magnet unit, a first to fourth magnetic pole section with a side length L of 13 mm and a separation distance D between the opposite side and the fixed side of 13 mm are used. It should be noted that the second and third magnetic pole sections are designated as N poles, and the first and fourth magnetic pole sections are designated as S poles. Furthermore, the magnetization direction of the second and third magnetic pole sections is orthogonal to the width direction of the fixed member, while the magnetization direction of the first and fourth magnetic pole sections is parallel to the width direction of the fixed member. By adopting this configuration, it is possible to achieve… Figure 5 The sputtering angle (angle θ) (approximately 42 degrees) in the magnet unit 75 of the first magnetron plasma unit 64 shown in the figure.

[0244] Vacuum exhaust is performed until the ultimate vacuum level in the film-forming chamber of the sputtering film-forming apparatus reaches 1.0 × 10⁻⁶. －4After Pa, argon gas as the sputtering gas and oxygen gas as the reactive gas are introduced into the film-forming chamber, and the pressure in the film-forming chamber is set to 0.2 Pa. It should be noted that argon and oxygen are introduced into the film-forming chamber at a volume ratio of 100:10. Furthermore, as the target for the sputtering film-forming apparatus, a sintered body of indium oxide and tin oxide is used, specifically a sintered body containing indium oxide and tin oxide in a mass ratio of 90:10. As the power source for applying voltage to the target, an MFAC power supply is used, with the discharge power set to 4.3 kW and the film-forming temperature (the temperature at which the transparent substrate film for the primer layer is formed) set to -8°C.

[0245] Thus, a primer layer is formed on the side of the transparent substrate film in the thickness direction (the side of the cured resin layer in the thickness direction).

[0246] [Formation of the anti-reflective layer]

[0247] Next, using a sputtering method, an alternating laminate (anti-reflective layer) is formed on one side of the primer layer along its thickness direction, comprising sequentially layers of 16 nm thick niobium oxide (first layer), 38 nm thick silicon oxide (second layer), 30 nm thick niobium oxide (third layer), and 98 nm thick silicon oxide (fourth layer). The anti-reflective layer is formed using methods such as... Figure 3 The image shows a roll-to-roll magnetron sputtering film deposition apparatus Z. It should be noted that the sputtering film deposition apparatus Z includes a film deposition chamber capable of moving the working film (a transparent substrate film with a primer layer) in a roll-to-roll manner and performing the film deposition process. Furthermore, the sputtering film deposition apparatus Z includes... Figure 6 The second magnetron plasma unit 64 shown in the figure has a magnet unit 75. Details of the magnet unit and sputtering conditions for forming the antireflective layer are shown below.

[0248] In the magnet unit, a first to a fourth magnetic pole section are used, with a side length L of 10 mm and a separation distance D between the opposite side and the fixed side of 20 mm. It should be noted that the second and third magnetic pole sections are designated as N poles, and the first and fourth magnetic pole sections are designated as S poles. Furthermore, the magnetization direction of the second and third magnetic pole sections is inclined relative to the thickness and width directions of the fixed member, and is set to intersect each other towards the center of the film-forming roller. The magnetization direction of the first and fourth magnetic pole sections is set along the width direction of the fixed member (parallel to the width direction of the fixed member). By adopting this configuration, it is possible to achieve… Figure 6 The sputtering angle (angle θ) (approximately 30 degrees) in the magnet unit 75 of the second magnetron plasma unit 64 shown in the figure.

[0249] In the first layer of film formation, vacuum degassing is performed until the ultimate vacuum level in the film formation chamber of the sputtering film formation apparatus reaches 1.0 × 10⁻⁶. －4After Pa, argon gas (as a sputtering gas, inert gas) and oxygen gas (as a reactive gas) are introduced into the film-forming chamber, and the pressure inside the chamber is set to 0.5 Pa. It should be noted that the argon and oxygen are introduced into the film-forming chamber at a volume ratio of 100:5. Furthermore, niobium is used as the target for the sputtering film-forming apparatus. An MFAC power supply is used as the power source for applying voltage to the target, with the discharge power set to 13 kW, and the film-forming temperature (the temperature of the transparent substrate film with a primer layer for forming the anti-reflective layer) set to -8 °C.

[0250] In the second layer of film formation, vacuum degassing is performed until the ultimate vacuum level in the film formation chamber of the sputtering film formation apparatus reaches 1.0 × 10⁻⁶. －4 After Pa, argon gas (an inert gas) is introduced into the film-forming chamber as the sputtering gas, and the pressure inside the chamber is set to 0.2 Pa. It should be noted that the flow rate of oxygen, as a reactive gas, is controlled using an impedance control method to form a film in the transition region. Furthermore, silicon is used as the target for the sputtering film-forming apparatus. An MFAC power supply is used as the power source for applying voltage to the target, with the discharge power set to 25 kW, and the film-forming temperature (the temperature of the transparent substrate film with a primer layer for forming the anti-reflective layer) set to -8 °C.

[0251] The film formation of the third layer is set under the same conditions as that of the first layer described above.

[0252] The fourth layer is formed under the same conditions as the second layer.

[0253] Thus, an alternating laminate (anti-reflective layer) is formed on the thickness side of the primer layer, consisting of a niobium oxide layer (first layer), a silicon oxide layer (second layer), a niobium oxide layer (third layer), and a silicon oxide layer (fourth layer) in sequence.

[0254] [Formation of the antifouling layer]

[0255] Then, an antifouling layer with a thickness of 6 nm is formed on one side of the antireflective layer (the side of the silicon oxide layer (fourth layer) in the thickness direction) by vacuum evaporation. As the material for the antifouling layer, a material obtained by drying an antifouling layer composition (trade name: KY1903-1, active ingredient: alkoxysilane compound containing a perfluoropolyether backbone, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) is used as the evaporation source, and the heating temperature of the evaporation source is set to 260°C.

[0256] Thus, an antifouling layer is formed on one side of the thickness direction of the antireflective layer (the side of the thickness direction of the silicon oxide layer (fourth layer)).

[0257] As described above, an anti-reflective film is formed.

[0258] Example 2

[0259] An antireflective layer is formed on one side of the primer layer in the thickness direction, consisting of an alternating laminate of a 5 nm thick niobium oxide layer (first layer) and a 130 nm thick silicon oxide layer (second layer) sequentially arranged in that direction. Otherwise, the antireflective film of Example 2 is fabricated in the same manner as the antireflective film of Example 1. In other words, in Example 2, the third and fourth layers are not formed in the antireflective layer; instead, an antifouling layer is formed on one side of the antireflective layer in the thickness direction (the side facing the thickness direction of the silicon oxide layer (second layer)).

[0260] Comparative Example 1

[0261] The same film-forming method as the primer layer is used in the film-forming of the anti-reflective layer. Figure 5 The first magnetron plasma unit 64 shown in the figure has a magnet unit 75, except that the antireflective film of Comparative Example 1 is made in the same way as the antireflective film of Example 1.

[0262] <Evaluation>

[0263] [FT-IR analysis]

[0264] Antireflective films for each embodiment and each comparative example were prepared, along with sample films obtained by removing the antifouling layer and the antireflective layer from the antireflective films for each embodiment and each comparative example. Infrared absorption spectra S1 were measured from one side of the thickness direction of each antireflective film, and infrared absorption spectra S2 were measured from one side of the thickness direction of each sample film using a Fourier transform infrared spectrophotometer (FT-IR) (product name: Frontier, manufactured by PerkinElmer). It should be noted that the measurements were performed at an incident angle of 45 degrees and a cumulative count of 256, using a Ge prism.

[0265] The sample film was obtained by etching the antifouling layer and the antireflective layer of the antireflective film of each embodiment and each comparative example in the following order.

[0266] Specifically, the antireflective films of each embodiment and comparative example were placed on a sample stage for Solidneblizer ICP-MS analysis. A femtosecond laser was used to irradiate the surface of the antireflective film (the surface on the antifouling layer side of the antireflective film) using a dissociation apparatus (ST Japan, Jupiter), etching the antifouling layer and antireflective layer by ablation. Compared to silicon oxide layers, niobium oxide layers tend to be more difficult to ablate. If etching is performed, even removing a portion of the transparent substrate film, the results at wavelengths exceeding 1000 cm⁻¹... －1The region where Si is detected affects the infrared absorption spectrum S2; therefore, the etching process was performed using a measuring device (iCAP TQ, Thermo Fisher Scientific) to conduct elemental analysis on the surface of the antireflective film, terminating at the region where Nb was detected but Si was not detected. The infrared absorption of Nb is at 1000 cm⁻¹. －1 The following parameters were detected, therefore even if small amounts remain, they will not be detected at wavelengths exceeding 1000 cm⁻¹. －1 The region affects the infrared absorption spectroscopy measurement. Thus, the sample film is obtained. It should be noted that in the sample film, for the ITO layer serving as the primer layer, since the difference between the infrared absorption spectrum S1 and the infrared absorption spectrum S2 is calculated, its influence can be ignored.

[0267] The infrared absorption spectrum S1 of the obtained antireflection film and the infrared absorption spectrum S2 of the sample film were compared using a 1730 cm⁻¹ infrared spectroscopy method. －1 The peaks originating from the C=O stretching vibrations of acrylates in the vicinity were normalized. Then, the difference spectrum was obtained by subtracting the infrared absorption spectrum S2 from the infrared absorption spectrum S1. From the obtained difference spectrum, the peak at 1050 cm⁻¹ was calculated. －1 The intensity of the maximum absorption peak near the Si-O-Si symmetric stretching peak is normalized to 1, and the 1200 cm⁻¹ peak is used as the reference value. －1 The absorption peak intensity originating from the Si-O-Si asymmetric stretching is set as 1 / X when X is denoted as X. The results are shown in Table 1. It should be noted that a large 1 / X indicates that the proportion of structures with Si-O-Si symmetric stretching is higher than that of structures with Si-O-Si asymmetric stretching.

[0268] [Indented elastic modulus]

[0269] In the antireflective films of each embodiment and comparative example, the indentation modulus at 10 nm was measured using a nanoindenter (product name: TriboIndenter, manufactured by Hysitron). Specifically, a Berkovich (triangular pyramidal) indenter was used to measure the indentation depth at 10 nm using a single indentation measurement on the thickness-direction side of each antireflective film (the thickness-direction side of the antifouling layer). The results are shown in Table 1. It should be noted that in antireflective films, a high indentation modulus at 10 nm on the thickness-direction side of the antifouling layer indicates excellent scratch resistance when sliding against materials such as steel wool.

[0270] [Abrasion resistance]

[0271] Using a 15 μm thick adhesive, the antireflective films of each embodiment and comparative example were adhered to a glass substrate to prepare test specimens. Next, steel wool #0000 was adhered to a 10 mm Φ metal clamp using adhesive in a heavy-duty liner abraser (product name: Taber 5800, manufactured by Taber). The test specimens were positioned so that the antireflective film was in contact with the steel wool, allowing the steel wool to slide. As for the sliding conditions, the load was set to 500 g, the test speed to 60 cycles / min, the stroke to 60 mm, and 5000 reciprocating slides were performed. Then, the presence or absence of damage was confirmed under a three-wavelength fluorescent lamp, and the evaluation was performed according to the following criteria. The results are shown in Table 1.

[0272] {Benchmark}

[0273] A: No damage occurred.

[0274] B: Damage occurs.

[0275] [Reflectivity]

[0276] Using a 15 μm thick adhesive, the antireflective films of each embodiment and comparative example were attached to a black acrylic plate to prepare test samples. The reflectance of each antireflective film was measured using a UV-Vis-IR spectrophotometer (product name: UH-4150, manufactured by Hitachi High Tech Science Co., Ltd.) on these test samples. It should be noted that the measurements were performed at wavelengths from 380 nm to 780 nm. The results are shown in Table 1.

[0277]

[0278] It should be noted that the above-described invention is provided as an example of the implementation of this invention, but is merely an example and not intended to be limiting. Variations of this invention that will be apparent to those skilled in the art are included in the technical solutions.

[0279] Industrial availability

[0280] The anti-reflective film 1 of the present invention is suitable for use in image display devices such as liquid crystal displays and organic EL displays. Specifically, in image display devices, in order to prevent external light from entering, the anti-reflective film 1 of the present invention is disposed on the outermost surface of the display screen.

[0281] Explanation of reference numerals in the attached figures

[0282] 1: Anti-reflective film; 2: Transparent substrate film; 3: Anti-reflective layer; 4: Anti-fouling layer; 5: Primer layer; 21: Transparent resin film; 22: Cured resin layer; 31: Niobium oxide layer; 32: Silicon oxide layer.

Claims

1. An antireflection film comprising, in order from the side of the thickness direction, a transparent base film, an antireflection layer, and a stain-proof layer, the transparent base film comprises a transparent resin film, the antireflection layer is an alternate laminate formed of at least one layer of a niobium oxide layer and at least one layer of a silicon oxide layer, the layer of the antireflection layer closest to the stain-proof layer is a silicon oxide layer, In the difference spectrum calculated from the Fourier transform infrared spectrophotometry (FT-IR) analysis, the intensity of the absorption peak at 1050 cm －1 near which the maximum absorption peak derived from the symmetric stretching of Si-O-Si is normalized to 1 is set to X, and the intensity of the absorption peak at 1200 cm －1 derived from the asymmetric stretching of Si-O-Si is set to 1, 1 / X is 5.0 or more, in FT-IR analysis, an infrared absorption spectrum SI is measured from the side of the thickness direction of the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer, and in addition, an infrared absorption spectrum S2 is measured from the side of the thickness direction of a sample film obtained by removing the antireflection layer and the stain-proof layer from the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer, and a difference spectrum of the infrared absorption spectrum SI and the infrared absorption spectrum S2 is calculated.

2. The antireflection film according to claim 1, wherein the transparent base film further comprises a cured resin layer disposed on the side of the thickness direction of the transparent resin film.

3. The antireflection film according to claim 1, wherein the antireflection film further comprises a primer layer disposed between the transparent base film and the antireflection layer, the primer layer is a metal oxide layer.

4. The antireflection film according to claim 1, wherein the 10 nm indentation elastic modulus of the side of the thickness direction of the stain-proof layer is 16 GPa or more.

5. A method for producing an antireflection film, which is the method for producing the antireflection film according to any one of claims 1 to 4, the antireflection layer is formed on the side of the thickness direction of the transparent base film by a sputtering method, the silicon oxide layer of the layer of the antireflection layer closest to the stain-proof layer is formed by a sputtering method with a sputtering angle of 35 degrees or less.

6. The method for producing an antireflection film according to claim 5, wherein the silicon oxide layer of the layer closest to the stain-proof layer is formed by a reactive sputtering method, in the formation of the silicon oxide layer of the layer closest to the stain-proof layer by the reactive sputtering method, oxygen is introduced using an impedance control method or a plasma emission monitoring control method (PEM control method) to be formed in a transition region between a metal region and an oxide region.

Images