Anti-reflection film and method for producing the same

Abstract

Provided are an anti-reflection film having excellent scratch resistance and a method for producing the anti-reflection film. [Solution] An antireflection film 1 comprises a transparent substrate film 2, an antireflection layer 3, and an antifouling layer 4, in this order toward one side in the thickness direction. The transparent substrate film 2 comprises a transparent resin film 21. The antireflection layer 3 is an alternating laminate consisting of at least one niobium oxide layer 31 and at least one silicon oxide layer 32, and the layer in the antireflection layer 3 closest to the antifouling layer 4 is the silicon oxide layer 32. In addition, in a difference spectrum calculated by Fourier transform infrared spectrophotometer analysis (FT-IR analysis), -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 When the absorption peak intensity resulting from the Si-O-Si asymmetric stretching is defined as X, 1 / X is 5.0 or more.

Description

[Technical Field]

[0001] The present invention relates to an anti-reflection film and a method for producing the same. [Background technology]

[0002] In image display devices such as liquid crystal displays and organic EL displays, an anti-reflection film is disposed on the outermost surface of the display screen to prevent external light from being reflected in. Such an anti-reflection film includes a transparent substrate film and an anti-reflection layer consisting of a high refractive index layer and a low refractive index layer.

[0003] Furthermore, in order to suppress adhesion of contaminants, an anti-reflection film further comprising an anti-fouling layer has been proposed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-079332 Summary of the Invention [Problem to be solved by the invention]

[0005] On the other hand, since an anti-reflection film is placed on the outermost surface of a display screen, it is required to have even better scratch resistance.

[0006] The present invention provides an anti-reflection film having excellent scratch resistance and a method for producing the anti-reflection film. [Means for solving the problem]

[0007] The present invention [1] is a film comprising a transparent substrate film, an antireflection layer, and an antifouling layer in this order toward one side in a thickness direction, the transparent substrate film comprising a transparent resin film, the antireflection layer being an alternating laminate comprising at least one niobium oxide layer and at least one silicon oxide layer, the layer in the antireflection layer closest to the antifouling layer being a silicon oxide layer, and in a difference spectrum calculated by the following Fourier transform infrared spectrophotometer analysis (FT-IR analysis), -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 The antireflection film includes an antireflection film in which 1 / X is 5.0 or more, where X is the absorption peak intensity resulting from the asymmetric Si-O-Si stretching. (FT-IR analysis) An infrared absorption spectrum S1 is measured from one side in the thickness direction of the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer, and an infrared absorption spectrum S2 is measured from one side in the thickness direction of a sample film obtained by removing the antireflection layer and the antifouling layer from the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer, and a difference spectrum between the infrared absorption spectrum S1 and the infrared absorption spectrum S2 is calculated.

[0008] The present invention [2] includes the anti-reflection film according to [1], wherein the transparent substrate film further comprises a cured resin layer disposed on one side in the thickness direction of the transparent resin film.

[0009] The present invention [3] includes the antireflection film according to [1] or [2], further comprising a primer layer disposed between the transparent substrate film and the antireflection layer, the primer layer being a metal oxide layer.

[0010] The present invention [4] includes the antireflection film according to any one of [1] to [3], wherein the antifouling layer has a 10 nm indentation elastic modulus of 16 GPa or more on one surface in the thickness direction.

[0011] The present invention [5] is a method for producing an antireflection film according to any one of [1] to [4], comprising forming the antireflection layer on one side in a thickness direction of the transparent substrate film by a sputtering method, and forming a silicon oxide layer in the antireflection layer closest to the antifouling layer by a sputtering method at a sputtering angle of 35 degrees or less.

[0012] The present invention [6] includes the method for producing an antireflection film according to [5], wherein the silicon oxide layer closest to the antifouling layer is deposited by a reactive sputtering method, and oxygen gas is introduced using an impedance control method or a PEM control method in depositing the silicon oxide layer closest to the antifouling layer by the reactive sputtering method so that the silicon oxide layer is deposited in a transition region between a metal region and an oxide region. [Effects of the Invention]

[0013] The anti-reflection film of the present invention has a peak at 1050 cm in the difference spectrum calculated by Fourier transform infrared spectrophotometer analysis (FT-IR analysis). -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 When the absorption peak intensity resulting from the Si-O-Si asymmetric stretching is defined as X, 1 / X is 5.0 or more. Therefore, the ratio of the structure having the Si-O-Si symmetric stretching to the structure having the Si-O-Si asymmetric stretching is high, and the abrasion resistance is excellent.

[0014] In the method for producing an antireflection film of the present invention, the silicon oxide layer in the antireflection layer closest to the antifouling layer is formed by sputtering at a sputtering angle of 35 degrees or less, thereby making it possible to produce an antireflection film with excellent scratch resistance. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 shows a cross-sectional view of one embodiment of the anti-reflection film of the present invention. [Figure 2] Figure 2 shows a method for producing the antireflection film shown in Figure 1. Figure 2A shows a step of preparing a transparent resin film, Figure 2B shows a step of forming a cured resin layer on the transparent resin film, Figure 2C shows a step of forming a primer layer on the cured resin layer, Figure 2D shows a step of forming an alternate laminate of niobium oxide layers and silicon oxide layers on the primer layer, and Figure 2E shows a step of forming an antifouling layer on the silicon oxide layer. [Figure 3] FIG. 3 shows a schematic diagram of a magnetron sputtering film formation apparatus used in the method for producing an anti-reflection film. [Figure 4] FIG. 4 is an enlarged cross-sectional view of a magnetron plasma unit provided in the magnetron sputtering film forming apparatus shown in FIG. [Figure 5] FIG. 5 shows a cross-sectional view of the magnet unit of the first magnetron plasma unit. [Figure 6] FIG. 6 shows a cross-sectional view of the magnet unit of the second magnetron plasma unit. DETAILED DESCRIPTION OF THE INVENTION

[0016] 1.Anti-reflective film An embodiment of the antireflection film of the present invention will be described with reference to FIG.

[0017] 1, the antireflection film 1 is in the form of a film (including a sheet) having a predetermined thickness. The antireflection film 1 extends in a plane direction perpendicular to the thickness direction, and one surface (upper surface) and the other surface (lower surface) in the thickness direction of the antireflection film 1 are flat.

[0018] The antireflection film 1 includes a transparent substrate film 2, an antireflection layer 3, and an antifouling layer 4, arranged in this order toward one side in the thickness direction. The antireflection film 1 may further include a primer layer 5 disposed between the transparent substrate film 2 and the antireflection layer 3. Specifically, as shown in FIG. 1 , the antireflection film 1 includes a transparent substrate film 2, a primer layer 5 disposed on one surface of the transparent substrate film 2 in the thickness direction, an antireflection layer 3 disposed on one surface of the primer layer 5 in the thickness direction, and an antifouling layer 4 disposed on one surface of the antireflection layer 3 in the thickness direction.

[0019] <Transparent substrate film> The transparent substrate film 2 is the bottom layer of the antireflection film 1. The transparent substrate film 2 also includes a transparent resin film 21. The transparent substrate film 2 may further include a cured resin layer 22 disposed on one side of the transparent resin film 21 in the thickness direction. The transparent substrate film 2 preferably includes the transparent resin film 21 and the cured resin layer 22 disposed on one surface of the transparent resin film 21 in the thickness direction. More preferably, the transparent substrate film 2 includes the transparent resin film 21 and the cured resin layer 22 disposed on one surface of the transparent resin film 21 in the thickness direction.

[0020] The transparent resin film 21 has a film shape (including a sheet shape) and is, for example, a flexible, transparent resin film.

[0021] Examples of materials for the transparent resin film 21 include cellulose resin, polyester resin, (meth)acrylic resin (acrylic resin and / or methacrylic resin), olefin resin, polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, polystyrene resin, norbornene resin, and polyvinyl alcohol resin. Examples of polyester resins include polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate. Examples of polyolefin resins include polyethylene, polypropylene, and cycloolefin polymer (COP). Examples of cellulose resins include triacetyl cellulose (TAC). From the viewpoints of transparency, heat resistance, mechanical strength, and the like, the transparent resin film 21 is preferably a cellulose-based film formed from a cellulose resin. More preferably, a triacetyl cellulose film is used. The materials for the transparent resin film 21 can be used alone or in combination of two or more.

[0022] The transparent resin film 21 has a total light transmittance (JISK-7105) of, for example, 80% or more, preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more, and for example, 100% or less.

[0023] The thickness of the transparent resin film 21 is not particularly limited, but from the viewpoint of strength and ease of handling, it 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, particularly preferably 50 μm or more, and for example, 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, even more preferably 150 μm or less, particularly preferably 100 μm or less.

[0024] The thickness of the transparent resin film 21 can be measured using, for example, a film thickness meter.

[0025] The cured resin layer 22 is a layer that improves the mechanical properties of the antireflection film 1. The cured resin layer 22 contacts one surface of the transparent resin film 21 in the thickness direction.

[0026] Examples of the cured resin layer 22 include a hard coat layer and an anti-blocking layer. The hard coat layer is, for example, a layer that makes it difficult for scratches to form on the exposed surface of the transparent resin film 21. The anti-blocking layer is, for example, a layer that imparts anti-blocking properties to the surfaces of multiple anti-reflection films 1 that come into contact with each other when the anti-reflection films 1 are stacked in the thickness direction.

[0027] The cured resin layer 22 is, for example, a cured product of a curable resin composition. Specifically, the cured resin layer 22 can be formed by applying a curable resin composition to one surface in the thickness direction of the transparent resin film 21, drying the composition as necessary, and then curing the composition.

[0028] The curable resin composition contains a curable resin. Examples of the curable resin include polyester resin, acrylic urethane resin, acrylic resin (excluding acrylic urethane resin), urethane resin (excluding acrylic urethane resin), amide resin, silicone resin, epoxy resin, and melamine resin. Preferred examples include acrylic urethane resin and acrylic resin (excluding acrylic urethane resin). The curable resin can be used alone or in combination of two or more types. Preferably, two or more types are used in combination.

[0029] Examples of the curable resin composition include an ultraviolet-curable resin composition and a thermosetting resin composition. From the viewpoint of production efficiency, an ultraviolet-curable resin composition is preferably used as the curable resin composition. The ultraviolet-curable resin composition contains at least one selected from the group consisting of an ultraviolet-curable monomer, an ultraviolet-curable oligomer, and an ultraviolet-curable polymer. A specific example of the ultraviolet-curable resin composition is a composition for forming a hard coat layer described in JP 2016-179686 A.

[0030] The curable resin composition preferably contains fine particles from the viewpoints of adjusting the hardness, surface roughness, refractive index, and anti-glare properties of the cured resin layer 22. Examples of the fine particles include inorganic particles and organic particles. Preferred examples include inorganic particles. Preferred examples of the inorganic particles include inorganic oxide particles. Examples of materials for the inorganic oxide particles include silica, alumina, titania, zirconia, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. Preferred examples include silica. Examples of materials for the organic particles include polymethyl methacrylate, polystyrene, polyurethane, acrylic-styrene copolymer, benzoguanamine, melamine, and polycarbonate.

[0031] When the curable resin composition is an ultraviolet-curable resin composition, it preferably contains a photopolymerization initiator.

[0032] Furthermore, the curable resin composition may contain additives such as, for example, a solvent, a leveling agent, a thixotropic agent, and an antistatic agent.

[0033] Examples of the solvent include butyl acetate, ethyl acetate, toluene, and cyclopentanone, and preferably butyl acetate.

[0034] 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 for example, 15 μm or less, preferably 12 μm or less, more preferably 10 μm or less.

[0035] When the thickness of the cured resin layer 22 is equal to or greater than the above lower limit, the cured resin layer 22 can be easily formed and the functions of the cured resin layer 22 can be fully exhibited. When the thickness of the cured resin layer is equal to or less than the above upper limit, the antireflection film 1 can be made thinner.

[0036] One surface in the thickness direction of the transparent substrate film 2 (one surface in the thickness direction of the cured resin layer 22) may be subjected to a surface modification treatment in order to improve adhesion to the primer layer 5 described below or the antireflection layer 3 described below. Preferably, the surface is modified. Examples of surface modification treatments include corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, glow treatment, saponification treatment, and treatment with a coupling agent. Preferably, plasma treatment is used.

[0037] The transparent substrate film 2 has a total light transmittance (JISK-7105) of, for example, 80% or more, preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more, and for example, 100% or less.

[0038] The thickness of the transparent substrate film 2 is not particularly limited, but from the viewpoint of strength and ease of handling, it 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, particularly preferably 50 μm or more, and for example, 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, even more preferably 150 μm or less, particularly preferably 100 μm or less.

[0039] <Primer layer> The primer layer 5 is an adhesive layer that improves the adhesion of the antireflection layer 3 laminated on the transparent substrate film 2. The primer layer 5 is disposed on one thickness-wise side of the transparent substrate film 2 and on the other thickness-wise side of the antireflection layer 3. Specifically, as shown in FIG. 1, the primer layer 5 is disposed on one thickness-wise surface of the transparent substrate film 2 (one thickness-wise surface of the cured resin layer 22). In other words, the primer layer 5 contacts the transparent substrate film 2 (cured resin layer 22).

[0040] Examples of materials for the primer layer 5 include metals such as nickel, chromium, indium, aluminum, tin, gold, silver, platinum, zinc, titanium, tungsten, zirconium, and palladium, alloys of two or more of these metals, and oxides of these metals. Examples of materials for the primer layer 5 also include semi-metals such as silicon and oxides of these metals.

[0041] Examples of metal oxides include indium-containing conductive oxides, antimony-containing conductive oxides, and zinc-containing conductive oxides. Examples of indium-containing conductive oxides include indium-tin composite oxide (ITO), indium-zinc composite oxide (IZO), indium-gallium composite oxide (IGO), and indium-gallium-zinc composite oxide (IGZO). Examples of antimony-containing conductive oxides include antimony-tin composite oxide (ATO). Examples of zinc-containing conductive oxides include zinc-aluminum composite oxide (AZO).

[0042] 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 to both the transparent substrate film 2 and the antireflection 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 composite oxide (ITO). In other words, the primer layer 5 is more preferably a metal oxide layer, and even more preferably an ITO layer.

[0043] In ITO used as a material for the primer layer, the content of tin oxide relative to the total amount of indium oxide and tin oxide is, for example, 1 mass% or more, preferably 3 mass% or more, more preferably 5 mass% or more, even more preferably 8 mass% or more, and for example, 50 mass% or less, preferably 45 mass% or less, more preferably 40 mass% or less, even more preferably 35 mass% or less.

[0044] 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, particularly preferably 3.0 nm or more, and 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, particularly preferably 8.0 nm or less.

[0045] When the thickness of the primer layer 5 is equal to or greater than the above lower limit, the adhesive strength between the transparent substrate film 2 and the antireflection layer 3 laminated on the primer layer 5 can be ensured.

[0046] <Anti-reflection layer> The antireflection layer 3 is a layer that suppresses the reflection intensity of external light. The antireflection layer 3 is disposed on one side in the thickness direction of the transparent substrate film 2. Specifically, the antireflection layer 3 is disposed on one surface in the thickness direction of the primer layer 5. In other words, the antireflection layer 3 is in contact with the primer layer 5.

[0047] The antireflection layer 3 is an alternating laminate consisting of high-refractive-index layers with a relatively high refractive index and low-refractive-index layers with a relatively low refractive index. In the antireflection layer 3, the reflection intensity of external light is suppressed by the interference between reflected light at multiple interfaces in the multiple thin layers (high-refractive-index layers and low-refractive-index layers). In addition, in the antireflection layer 3, the interference effect that suppresses the reflection intensity can be exerted by adjusting the optical film thickness (product of refractive index and thickness) of each thin layer.

[0048] Specifically, the antireflection layer 3 is an alternating laminate consisting 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. In the antireflection layer 3, the layer closest to the antifouling layer 4 is the silicon oxide layer 32. In other words, the uppermost layer (the layer located on one side in the thickness direction) in the antireflection layer 3 is the silicon oxide layer 32. Preferably, the layer closest to the transparent substrate film 2 in the antireflection layer 3 is the niobium oxide layer 31. In other words, the lowermost layer (the layer located on the other side in the thickness direction) in the antireflection layer 3 is the niobium oxide layer 31.

[0049] More specifically, as shown in FIG. 1, in one embodiment of the antireflection film, the antireflection layer 3 is an alternating laminate consisting of a niobium oxide layer 31a (first layer), a silicon oxide layer 32a (second layer), a niobium oxide layer 31b (third layer), and a silicon oxide layer 32b (fourth layer).

[0050] In one embodiment of the antireflection film, as shown in FIG. 1 , 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). In the antireflection layer 3, the layer closest to the antifouling layer 4 is the silicon oxide layer 32b (fourth layer).

[0051] The niobium oxide layer 31 is a layer made of niobium oxide. The silicon oxide layer 32 is a layer made of silicon oxide. The niobium oxide layer 31 and the silicon oxide layer 32 may contain trace amounts of unavoidable impurities.

[0052] As described above, the niobium oxide layer 31 has a relatively high refractive index, and the silicon oxide layer 32 has a relatively low refractive index. Specifically, the refractive index of the niobium oxide layer 31 at a wavelength of 550 nm is 2.33. The refractive index of the silicon oxide layer 32 at a wavelength of 550 nm is 1.46.

[0053] 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, even more preferably 10 nm or more, and for example, 50 nm or less, preferably 30 nm or less, more preferably 25 nm or less, even more preferably 20 nm or less.

[0054] 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, even more preferably 20 nm or more, and for example, 200 nm or less, preferably 100 nm or less, more preferably 60 nm or less, even more preferably 40 nm or less.

[0055] 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, particularly preferably 30 nm or more, and for example, 300 nm or less, preferably 200 nm or less, more preferably 100 nm or less, even more preferably 80 nm or less, particularly preferably 60 nm or less.

[0056] When the alternate 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).

[0057] 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 for example, 300 nm or less, preferably 200 nm or less, more preferably 150 nm or less.

[0058] 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, even more preferably 70 nm or less, and for example, 300 nm or more, preferably 200 nm or more, more preferably 150 nm or more, even more preferably 120 nm or more.

[0059] 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, even more preferably 100 nm or more, and for example, 500 nm or less, preferably 300 nm or less, more preferably 200 nm or less, even more preferably 150 nm or less.

[0060] When the alternate stack 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).

[0061] The total thickness of the antireflection layer 3 (alternate laminate) is, for example, 50 nm or more, preferably 100 nm or more, more preferably 130 nm or more, even more preferably 150 nm or more, and for example, 800 nm or less, preferably 500 nm or less, more preferably 300 nm or less, even more preferably 200 nm or less.

[0062] If the total thickness of the antireflection layer 3 (alternate laminate) is equal to or greater than the above lower limit, the reflection intensity of external light can be suppressed. If the total thickness of the antireflection layer 3 (alternate laminate) is equal to or less than the above upper limit, cracking of the antireflection layer 3 can be suppressed.

[0063] 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, particularly preferably 20% or more, and for example, 80% or less, preferably 60% or less, more preferably 40% or less, even more preferably 35% or less, particularly preferably 30% or less.

[0064] 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, even more preferably 65% ​​or more, particularly preferably 70% or more, and for example, 99% or less, preferably 97% or less, more preferably 90% or less, even more preferably 85% or less, particularly preferably 80% or less.

[0065] That is, the thickness (total thickness) of the silicon oxide layer 32 is preferably greater than the thickness (total thickness) of the niobium oxide layer 31.

[0066] One surface in the thickness direction of the antireflection layer 3 (the surface in contact with the antifouling layer 4) may be subjected to a surface modification treatment. Examples of surface modification treatments include corona treatment, plasma treatment, ozone treatment, primer treatment, glow treatment, and coupling agent treatment.

[0067] The surface roughness Ra (arithmetic mean surface roughness) of one surface in the thickness direction of the antireflection layer 3 (the surface in contact with the antifouling layer 4) is, for example, 0.5 nm or more, preferably 0.8 nm or more, and for example, 10 nm or less, preferably 8 nm or less.

[0068] The surface roughness Ra can be determined, for example, from an image of a 1 μm square observed by an AFM (atomic force microscope).

[0069] <Anti-fouling layer> The antifouling layer 4 is a layer that prevents contamination from the external environment and facilitates the removal of adhered contaminants. The antifouling layer 4 also has water vapor barrier properties. The antifouling layer 4 is the uppermost layer of the antireflection film 1.

[0070] The material of the antifouling layer 4 is not particularly limited, and examples thereof include compounds having a siloxane skeleton represented by the chemical formula -Si-O-Si-. That is, the antifouling layer 4 contains, for example, a compound having a siloxane skeleton, and is preferably made of a compound having a siloxane skeleton. Preferred examples of such compounds having a siloxane skeleton include alkoxysilane compounds having a dimethylsiloxane skeleton. Examples of alkoxysilane compounds having a dimethylsiloxane skeleton include compounds represented by the following general formula (1):

[0071] R1-X-(Si(CH3)2-O) n -Si(OR2)3(1)

[0072] Examples of R include alkylsilyl groups in which one or more hydrogen atoms in a hydrosilyl group (SiH-) are substituted with alkyl groups. Examples of alkylsilyl groups include trimethoxysilyl groups (Si(CH-).

[0073] R2 is, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group.

[0074] X is, for example, an ether group, a carbonyl group, an amino group, or an amide group, and is preferably an ether group.

[0075] n is an integer of, for example, 1 to 50, preferably 10 to 40, and more preferably 20 to 30.

[0076] That is, the alkoxysilane compound containing a dimethylsiloxane skeleton preferably includes a compound represented by the following general formula (2).

[0077] Si(CH3)3-O-(Si(CH3)2-O) m -Si(OCH3)3(2)

[0078] m is an integer of, for example, 1 to 50, preferably 10 to 40, or more preferably 20 to 30.

[0079] The alkoxysilane compounds containing a dimethylsiloxane skeleton may be used alone or in combination of two or more kinds.

[0080] If the material of the antifouling layer 4 contains an alkoxysilane compound containing a dimethylsiloxane skeleton, the antifouling function of the antifouling layer 4 can be improved.

[0081] Materials for the antifouling layer 4 include organic fluorine compounds having a terminal structure (terminal structure E) represented by the chemical formula CF3OCF2-. Such organic fluorine compounds are preferably alkoxysilane compounds having a perfluoropolyether skeleton. Examples of alkoxysilane compounds having terminal structure E and a perfluoropolyether skeleton include compounds represented by the following general formula (3):

[0082] CF3-OCF2-R3-Y-(CH2) r -Si(OR4)3(3)

[0083] R3 represents a structure containing at least one repeating unit of a perfluoropolyether (PFPE) group, and preferably represents a structure containing two repeating units of a PFPE group. R4 is, for example, an alkyl group having 1 to 4 carbon atoms, and preferably a methyl group. Y is, for example, an ether group, a carbonyl group, an amino group, or an amide group, and preferably an ether group. r is, for example, an integer of 1 to 20, preferably 1 to 10, and more preferably 1 to 5.

[0084] 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 particularly preferably 101° to 130°.

[0085] When the water contact angle on the outer surface of the antifouling layer 4 is equal to or greater than the above lower limit, the antifouling layer 4 has high antifouling properties.

[0086] The water contact angle is determined by forming a water droplet (pure water droplet) with a diameter of 2 mm or less on the outer surface of the antifouling layer 4 and measuring the contact angle of the water droplet with the outer surface of the antifouling layer 4. The water contact angle of the outer surface of the antifouling layer 4 can be adjusted by, for example, adjusting the composition of the antifouling layer 4, the roughness of the outer surface, and the composition of other layers.

[0087] 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, even more preferably 3.0 nm or more, and for example, 50 nm or less, preferably 30 nm or less, more preferably 10 nm or less, even more preferably 8.0 nm or less.

[0088] The antifouling layer 4 preferably has a small difference in refractive index from the layer with which it is in contact. 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.

[0089] The thickness of the antireflection 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, particularly preferably 50 μm or more, and for example, 300 μm or less, preferably 250 μm or less, more preferably 200 μm or less, even more preferably 170 μm or less, particularly preferably 150 μm or less.

[0090] The reflectance of the antireflection film 1 is, for example, 0.0% or more, and, for example, 8.0% or less, preferably 5.0% or less, more preferably 4.0% or less, even more preferably 2.0% or less, and particularly preferably 1.0% or less.

[0091] The reflectance of the antireflection film 1 can be measured using an ultraviolet-visible-infrared spectrophotometer. More specifically, it can be measured by the method described in the examples below.

[0092] In the anti-reflection film 1, the difference spectrum calculated by the following Fourier transform infrared spectrophotometer analysis (FT-IR analysis) shows a peak at 1050 cm -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 When the absorption peak intensity due to the Si-O-Si asymmetric stretching is X, 1 / X is, for example, 5.0 to 10.0, preferably 5.5 to 9.5, more preferably 6.0 to 9.0, even more preferably 6.5 to 8.5, particularly preferably 6.6 to 8.3, and most preferably 6.7 to 8.0.

[0093] In the anti-reflection film 1, the difference spectrum calculated by the following Fourier transform infrared spectrophotometer analysis (FT-IR analysis) shows a peak at 1050 cm -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 When the absorption peak intensity due to the Si-O-Si asymmetric stretching is 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, most preferably 6.7 or more, and for example, 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, most preferably 8.0 or less.

[0094] In the anti-reflection film 1, the difference spectrum calculated by the following Fourier transform infrared spectrophotometer analysis (FT-IR analysis) shows a peak at 1050 cm -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 When the absorption peak intensity resulting from the Si-O-Si asymmetric stretching is defined as X, if 1 / X is equal to or greater than the lower limit, the ratio of the structure having the Si-O-Si symmetric stretching to the structure having the Si-O-Si asymmetric stretching becomes high, resulting in excellent scratch resistance.

[0095] (FT-IR analysis) An infrared absorption spectrum S1 is measured from one side in the thickness direction of the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer, and an infrared absorption spectrum S2 is measured from one side in the thickness direction of a sample film obtained by removing the antireflection layer and the antifouling layer from the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer. Then, the infrared absorption spectrum S1 and the infrared absorption spectrum S2 are measured from one side in the thickness direction of the sample film obtained by removing the antireflection layer and the antifouling layer from the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer. -1 The spectrum is normalized by the peak derived from the C=O stretching vibration of the acrylate ester in the vicinity. The difference spectrum is calculated by subtracting the infrared absorption spectrum S2 from the normalized infrared absorption spectrum S1.

[0096] The infrared absorption spectrum S1 and the infrared absorption spectrum S2 can be measured using a Fourier transform infrared spectrophotometer (FT-IR), and a specific measurement method will be described in the Examples below.

[0097] Furthermore, as will be described in detail in the Examples below, in a sample film obtained by removing the antifouling layer and the antireflection layer from the antireflection film, if the entire antireflection layer is removed, there is a risk that a part of the transparent substrate film will also be removed. -1 Because of the influence on the infrared absorption spectrum S2 in the excess region, removal of the anti-reflection layer stops at the niobium oxide layer closest to the transparent substrate film (specifically, the region where Nb element is detected by elemental analysis). The infrared absorption of Nb element is 1000 cm -1 Even if a small amount remains, it can be detected at a wavelength of 1000 cm or less. -1 The infrared absorption spectrum S2 in the excess region is not affected.

[0098] Furthermore, even when the antireflection film includes a primer layer, the influence of the primer layer can be ignored because the difference spectrum between the infrared absorption spectrum S1 and the infrared absorption spectrum S2 is calculated.

[0099] In the antireflection film 1, the 10 nm indentation elastic modulus of the antifouling layer 4 on one surface in the thickness direction 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.

[0100] In the antireflection film 1, the 10 nm indentation elastic modulus of the antifouling layer 4 on one surface in the thickness direction 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, and 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.

[0101] In the antireflection film 1, if the 10 nm indentation modulus of the antifouling layer 4 on one surface in the thickness direction is equal to or greater than the above lower limit, the antireflection film 1 has excellent abrasion resistance when sliding with steel wool, etc. Furthermore, if the 10 nm indentation modulus of the antifouling layer 4 on one surface in the thickness direction is equal to or less than the above upper limit, the occurrence of cracks, etc. can be suppressed.

[0102] In the antireflection film 1, the 10 nm indentation modulus of one surface in the thickness direction of the antifouling layer 4 refers to the modulus of elasticity when the indentation depth is 10 nm. More specifically, it can be measured by the method described in the examples below.

[0103] 2. Anti-reflection film manufacturing method The method for producing the antireflection film of the present invention will be described with reference to FIGS. 2A to 2E.

[0104] The method for producing the antireflection film 1 includes, for example, a preparation step (FIG. 2A) of preparing a transparent resin film 21, a cured resin layer formation step (FIG. 2B) of forming a cured resin layer 22 on the transparent resin film 21, a primer layer formation step (FIG. 2C) of forming a primer layer 5 on the cured resin layer 22, an antireflection layer formation step (FIG. 2D) of forming an alternate laminate of niobium oxide layers 31 and silicon oxide layers 32 on the primer layer 5, and an antifouling layer formation step (FIG. 2E) of forming an antifouling layer 4 on the antireflection layer 3. The primer layer formation step and the antireflection layer formation step are performed sequentially using a sputtering deposition apparatus Z as shown in FIG.

[0105] <Preparation process> In the preparation step, as shown in FIG. 2A, a transparent resin film 21 is prepared.

[0106] <Cured resin layer formation process> 2B, in the cured resin layer forming step, a cured resin layer 22 is formed on one surface in the thickness direction of the transparent resin film 21. Specifically, the curable resin composition described above is applied to one surface in the thickness direction of the transparent resin film 21 to form a coating film, and then the coating film is cured to form the cured resin layer 22.

[0107] When the curable resin composition contains a solvent, the coating film on the transparent resin film 21 is dried after the curable resin composition is applied.

[0108] The drying temperature is, for example, 50° C. to 120° C. The drying time is, for example, 10 seconds to 10 minutes.

[0109] When the curable resin composition contains an ultraviolet-curable resin, the coating film on the transparent resin film 21 is cured by ultraviolet irradiation. Examples of the light source for ultraviolet irradiation include a high-pressure mercury lamp and an LED light. The cumulative irradiation amount of ultraviolet light is, for example, 100 mJ / cm. 2 ~500mJ / cm 2 is.

[0110] In this manner, a transparent substrate film 2 is obtained, which includes the cured resin layer 22 on one surface in the thickness direction of the transparent resin film 21. In this embodiment, a roll of the transparent substrate film 2 is prepared. Specifically, the transparent substrate film 2 is wound so that the surface of the transparent substrate film 2 on the cured resin layer 22 side faces inward in the roll radial direction.

[0111] [Sputtering deposition equipment Z] In the method for manufacturing the antireflection film 1, a primer layer forming step and an antireflection layer forming step are then carried out in sequence while the transparent substrate film 2 is transported as a workpiece film W by a roll-to-roll method under a reduced pressure atmosphere. A magnetron sputtering film forming apparatus Z, which is an example of an apparatus for carrying out the primer layer forming step and the antireflection layer forming step, will be described with reference to Figures 3 and 4.

[0112] As shown in FIG. 3, the sputtering film formation apparatus Z includes a transfer section P1 and a film formation section P2.

[0113] The conveying section P1 includes a conveying casing 51, a delivery roll 52, a take-up roll 53, a guide roll 54, and a vacuum pump 55.

[0114] The transport casing 51 has a generally box-like shape extending along the transport direction and accommodates a delivery roll 52, a take-up roll 53, and a guide roll .

[0115] The feed roll 52 and the take-up roll 53 are arranged at the upstream end and downstream end in the conveying direction within the conveying casing 51, respectively. A roll of transparent substrate film 2 is attached to the feed roll 52 as the workpiece film W. The take-up roll 53 is a roll for taking up the workpiece film W. A plurality of guide rolls 54 are arranged between the feed roll 52 and the take-up roll 53. The plurality of guide rolls 54 are arranged so as to wind the transparent substrate film 2 around the film-forming roll 63.

[0116] The vacuum pump 55 is provided in the conveying casing 51 .

[0117] The film forming section P2 includes a film forming casing 61, a film forming roll 63, and a plurality of magnetron plasma units 64.

[0118] The film formation casing 61 is continuous with the transport casing 51 and together with the transport casing 51 constitutes a vacuum chamber. The film formation casing 61 has a substantially box shape. The film formation casing 61 has a plurality of partition walls 62. The plurality of partition walls 62 extend toward the film formation roll 63. A sputtering gas supply device (not shown) is provided in the film formation casing 61. The film formation casing 61 houses the film formation roll 63 and a plurality of magnetron plasma units 64.

[0119] The film-forming roll 63 has an axis extending along the width direction of the transparent substrate film 2, which is perpendicular to the transport direction and thickness direction of the transparent substrate film 2.

[0120] The magnetron plasma units 64 are arranged facing each other on the radially outer side of the film-forming roll 63. The magnetron plasma units 64 are arranged at intervals from each other along the circumferential direction of the film-forming roll 63.

[0121] Circumferentially adjacent magnetron plasma units 64 are separated by partition walls 62. The spaces separated by partition walls 62 form film formation chambers R. The film formation chambers R are separated into multiple chambers (e.g., a first film formation chamber R1, a second film formation chamber R2, a third film formation chamber R3, and a fourth film formation chamber R4) within the film formation casing 61 (vacuum chamber). One magnetron plasma unit 64 is provided in one film formation chamber R. As shown in FIG. 4, each of the multiple magnetron plasma units 64 includes a plasma casing 71, a first unit 72, and a second unit 73.

[0122] The plasma casing 71 has a generally box-like shape with one side open toward the film-forming roll 63. The plasma casing 71 extends along the axis of the film-forming roll 63. The plasma casing 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 at an interval along the circumferential direction of the film-forming roll 63. The first unit 72 and the second unit 73 face the film-forming roll 63 through the opening of the plasma casing 71.

[0123] The first unit 72 and the second unit 73 have the same configuration except for the direction of rotation of the rotary target 74 (described below). Therefore, the first unit 72 will be described in detail, and the second unit 73 will be briefly described. Note that Fig. 5 shows the magnet unit 75 of the first magnetron plasma unit 64 used to form the primer layer 5, and Fig. 6 shows the magnet unit 75 of the second magnetron plasma unit 64 used to form the antireflection layer 3.

[0124] As shown in FIG. 4, the first unit 72 includes a rotary target 74 and a magnet unit 75.

[0125] The rotary target 74 has a cylindrical shape and has an axis AL (center in cross-sectional view, see FIGS. 5 and 6) parallel to the axis of the film-forming roll 63. The rotary target 74 is, for example, rotatable (movable around) in the direction opposite to the rotation direction of the film-forming roll 63. The rotary target 74 is electrically connected to a cathode source (not shown), and can thereby function as a cathode. In addition, a target material is laminated on the outer peripheral surface of the rotary target 74. The target material may be the material of the primer layer 5 described above, niobium or niobium suboxide (NbO X , X<2.5) (the material of the niobium oxide layer 31) and silicon (the material of the silicon oxide layer 32).

[0126] The magnet unit 75 is housed radially inside the rotary target 74. As shown in FIGS. 5 and 6, the magnet unit 75 includes a fixing member 80, two first magnets 81, and two second magnets 82.

[0127] The fixing member 80 has a narrow plate shape extending in the axial direction of the film-forming roll 63 and is called a yoke. One thickness direction surface (one main surface 83) and the other thickness direction surface (the other main surface) of the fixing member 80 are both flat surfaces. One main surface 83 faces the film-forming roll 63. The other main surface is parallel to the one main surface 83. Examples of materials for the fixing member 80 include metals such as iron.

[0128] Each of the two first magnets 81 and the two second magnets 82 has a rectangular prism shape extending along the axial direction of the film forming roll 63. The two first magnets 81 and the two second magnets 82 are fixed to one main surface 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.

[0129] The two first magnets 81 and the two second magnets 82 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 when viewed in a cross section along the width and thickness directions of the fixed member 80 (corresponding to directions perpendicular to the axis of the rotary target 74).

[0130] 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 in this order along one circumferential direction (the rotation direction of the rotary 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 in this order toward one widthwise side of the fixed member 80 so as to be in contact with one another.

[0131] The second magnetic pole portion 92 and the third magnetic pole portion 93 are formed from two first magnets 81. The second magnetic pole portion 92 and the third magnetic pole portion 93 have, for example, an N pole. The first magnetic pole portion 91 and the fourth magnetic pole portion 94 are formed from, for example, the second magnet 82. The first magnetic pole portion 91 and the fourth magnetic pole portion 94 have, for example, an S pole.

[0132] In a 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 the same substantially rectangular shape. In a 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 substantially rectangular shape having a fixed side 95 fixed to one main surface 83 of the fixed member 80, an opposite side 96 located opposite the fixed side 95, and two side sides 97 connecting both end edges thereof.

[0133] A fixed side 95 of 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 is disposed on one main surface 83 of the fixed member 80. An opposite side 96 of 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 is parallel to one main surface 83 of the fixed member 80. The opposite sides 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, and specifically, are flush (form a single flat surface).

[0134] The thickness and width lengths of the first magnetic pole part 91, the second magnetic pole part 92, the third magnetic pole part 93 and the fourth magnetic pole part 94 vary depending on the sputtering angle that is set.

[0135] In the magnet unit 75 of the first magnetron plasma unit 64 shown in Figure 5, the ratio (D / L) of the thickness direction length and width direction length of 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, i.e., the distance D between the opposite side 96 and the fixed side 95 to the length L of the opposite side 96, is, for example, 0.8 to 1.2, preferably 0.9 to 1.1, and more preferably 1.0.

[0136] In the magnet unit 75 of the first magnetron plasma unit 64 shown in Figure 5, the thickness and width lengths 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 to each other.

[0137] If the ratio (D / L) is within the above range, the sputtering angle (angle θ) will be as follows.

[0138] 5, the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 in a cross-sectional view are parallel to the thickness direction of the fixed member 80 (direction perpendicular to the width direction of the fixed member 80). The magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 are parallel to the width direction of the fixed member 80 (direction perpendicular to the thickness direction of the fixed member 80). If the magnetization directions are in the above-mentioned directions, the following sputtering angle (angle θ) is obtained.

[0139] The sputtering angle (angle θ) in the magnet unit 75 of the first magnetron plasma unit 64 shown in FIG. 5 is, for example, 35 to 50 degrees, preferably 37 to 48 degrees, more preferably 39 to 46 degrees, and even more preferably 40 to 45 degrees.

[0140] The sputtering angle (angle θ) in the magnet unit 75 of the first magnetron plasma unit 64 shown in FIG. 5 is, for example, 35 degrees or more, preferably 37 degrees or more, more preferably 39 degrees or more, even more preferably 40 degrees or more, and for example, 50 degrees or less, preferably 48 degrees or less, more preferably 46 degrees or less, even more preferably 45 degrees or less.

[0141] The sputtering angle is the angle θ shown below. The tangential component of the magnetic flux density is measured on the outer peripheral surface of the rotary target 74 in one circumferential direction of the rotary target. The angle θ is determined between a line segment LS1 connecting the point MAX_P corresponding to the maximum tangential component of the magnetic flux density and the center of the rotary target 74, and a line segment LS2 connecting the point MIN_P corresponding to the minimum tangential component of the magnetic flux density and the center. The angle θ can be determined, for example, by simulating a magnetic field using commercially available software.

[0142] Here, the tangential component of the magnetic flux density obtained by the above simulation will be explained.

[0143] 5 and 6, in the first unit 72, a tunnel-shaped first magnetic field MF1 (depicted by a plurality of dots) is generated from the opposite side of the second magnetic pole portion 92 having an N pole toward the opposite side of the first magnetic pole portion 91 having an S pole. If the second magnetic pole portion 92 is an N pole and the first magnetic pole portion 91 is an S pole, the minimum of the magnetic flux density (i.e., the strongest value of the magnetic field on the negative side, MIN_P) can be obtained by measuring the tangential component of the magnetic flux density in one direction, from the first magnetic pole portion 91 toward the second magnetic pole portion 92, in the circumferential direction of the rotary target 74.

[0144] Furthermore, a tunnel-shaped second magnetic field MF2 (drawn with multiple dots) is generated from the opposite side of the third magnetic pole portion 93 having an N pole toward the opposite side of the fourth magnetic pole portion 94 having an S pole. If the third magnetic pole portion 93 is an N pole and the fourth magnetic pole portion 94 is an S pole, the maximum of the magnetic flux density (i.e., 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 one direction, from the third magnetic pole portion 93 toward the fourth magnetic pole portion 94, which is the circumferential direction of the rotary target 74.

[0145] The point MAX_P corresponding to the maximum tangential component of the magnetic flux density and the point MIN_P corresponding to the minimum tangential component are synonymous with the points corresponding to two maxima in the absolute value of the tangential component of the magnetic flux density.

[0146] The sputtering angle (angle θ) is the angle on the deposition roll 63 side of the angles formed by the two line segments LS1 and LS2.

[0147] In the magnet unit 75 of the first magnetron plasma unit 64 shown in Figure 5, the sputtering angle is such that, on the radial outside of the rotary target 74, the circumferential distance between the plasma corresponding to the maximum tangential component of the magnetic flux density and the plasma corresponding to the minimum tangential component of the magnetic flux density becomes large.

[0148] On the other hand, in the magnet unit 75 of the second magnetron plasma unit 64 shown in Figure 6, the ratio (D / L) of the thickness direction length and width direction length of 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, i.e., the 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, even more preferably 1.6 to 6.0, and particularly preferably 1.7 to 6.0.

[0149] In the magnet unit 75 of the second magnetron plasma unit 64 shown in Figure 6, the ratio (D / L) of 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, i.e., the ratio of the distance D (length of the 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, even more preferably 1.6 or more, particularly preferably 1.7 or more, and also, for example, 6.0 or less.

[0150] If the ratio (D / L) is within the above range, the sputtering angle (angle θ) will be as follows.

[0151] 6, in a cross-sectional view, the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 are inclined in the thickness direction and width direction of the fixed member 80, and the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 are in a direction parallel to the width direction of the fixed member 80 (a direction perpendicular to the thickness direction of the fixed member 80). Note that the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 may also be inclined in the thickness direction and width direction of the fixed member 80.

[0152] Specifically, the magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 are inclined in the thickness direction of the fixed member 80 toward the film deposition roll 63, so as to intersect with each other.

[0153] In addition, when the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 also incline in the thickness direction and width direction of the fixed member 80, the magnetization directions of the first magnetic pole portion 91 and the fourth magnetic pole portion 94 incline in directions that intersect with each other as they move away from the film-forming roll 63 in the thickness direction of the fixed member 80.

[0154] The magnetization directions of the second magnetic pole portion 92 and the third magnetic pole portion 93 intersect with each other, thereby concentrating the magnetic flux on the surface of the rotary target 74. As a result, the two tunnel-shaped magnetic fields approach each other, forming the sputtering angle (angle θ) shown below. Specifically, the sputtering angle (angle θ) in the magnet unit 75 of the second magnetron plasma unit 64 shown in FIG. 6 is smaller than the sputtering angle (angle θ) in the magnet unit 75 of the first magnetron plasma unit 64 shown in FIG. 5.

[0155] The sputtering angle (angle θ) in the magnet unit 75 of the second magnetron plasma unit 64 shown in FIG. 6 is, for example, 10 to 35 degrees, preferably 15 to 34 degrees, more preferably 20 to 33 degrees, and even more preferably 22 to 32 degrees.

[0156] The sputtering angle (angle θ) in the magnet unit 75 of the second magnetron plasma unit 64 shown in FIG. 6 is, for example, 10 degrees or more, preferably 15 degrees or more, more preferably 20 degrees or more, even more preferably 22 degrees or more, and for example, 35 degrees or less, preferably 34 degrees or less, more preferably 33 degrees or less, even more preferably 32 degrees or less.

[0157] Furthermore, when the sputtering angle (angle θ) is within the above range, the circumferential distance between the plasma corresponding to the maximum tangential component of magnetic flux density and the plasma corresponding to the minimum tangential component of magnetic flux density becomes shorter on the radially outer side of the rotary target 74. This allows for a concentrated area of ​​high density electrons emitted from the rotary target 74. In other words, the maximum magnetic flux density at point MAX_P can be increased. As a result, the proportion of the structure having symmetric Si-O-Si stretching relative to the structure having asymmetric Si-O-Si stretching in the silicon oxide layer 32 closest to the antifouling layer 4 can be increased, thereby enabling the production of an antireflection film with excellent scratch resistance. Furthermore, when the sputtering angle (angle θ) is equal to or greater than the above lower limit, the magnetic flux density can be prevented from becoming excessively low. In other words, the minimum magnetic flux density at point MIN_P can be reduced, allowing for sustained plasma generation.

[0158] The first magnet 81 and the second magnet 82 may be made of a permanent magnet such as a neodymium magnet.

[0159] As shown in FIG. 4, the second unit 73 includes a rotary target 74 that can rotate in the same direction as the rotation direction of the film-forming roll 63, and the magnet unit 75 described above.

[0160] The second unit 73 has the same configuration as the first unit 72.

[0161] <Primer layer formation process> Specifically, in the primer layer 5 formation step, the material for the primer layer 5 described above is formed into a film by sputtering on one surface in the thickness direction of the transparent substrate film 2 (one surface in the thickness direction of the cured resin layer 22) to form the primer layer 5. In other words, the primer layer 5 is a sputtered layer.

[0162] In the sputtering method, a sputtering deposition apparatus Z as described above is used, which can perform the film formation process using a roll-to-roll method. When a roll-to-roll sputtering deposition apparatus is used in the primer layer formation process, the transparent substrate film 2 as the workpiece film W is run from a delivery roll to a take-up roll provided in the apparatus, while the material for the primer layer 5 is formed on one surface of the transparent substrate film 2 in the thickness direction, thereby forming the primer layer 5. The running speed of the workpiece film W (transparent substrate film 2) is, for example, 0.5 to 10.0 m / min. In the primer layer formation process, a magnet unit 75 provided in the first magnetron plasma unit 64 shown in Figure 5 is used.

[0163] In the sputtering method used in the primer layer formation process, a sputtering deposition apparatus having one deposition chamber may be used, or a sputtering deposition apparatus having multiple deposition chambers (R1 to R4) arranged in sequence along the travel path of the work film W (transparent substrate film 2) as shown in Figure 3 may be used.

[0164] Specifically, in the sputtering method, a sputtering gas (inert gas) is introduced into the film-forming chamber R under vacuum conditions, while a negative voltage is applied to the target placed on the outer periphery of the rotary target 74 in the film-forming chamber R. This generates a glow discharge, ionizing the gas atoms, causing these gas ions to collide with the target surface at high speed, ejecting target material from the target surface, and depositing the ejected target material on one side of the workpiece film W (transparent substrate film 2) in the thickness direction. As the target material, for example, a sintered body of the material for the primer layer 5 described above is used.

[0165] Examples of sputtering gases include argon, krypton, xenon, and mixtures thereof, preferably argon. The sputtering method is preferably a reactive sputtering method. In the reactive sputtering method, for example, oxygen as a reactive gas is introduced into the deposition chamber in addition to the sputtering gas. That is, the primer layer 5 is deposited in the presence of an inert gas and oxygen gas.

[0166] The ultimate vacuum level in the deposition chamber before sputter deposition is, for example, 1.5 × 10 -4 Pa or less.

[0167] In the reactive sputtering method, the volume ratio of oxygen gas to the total volume of sputtering gas and oxygen gas (reactive gas) introduced into the film formation chamber is, for example, 1 volume % to 30 volume %, preferably 3 volume % to 20 volume %, more preferably 5 volume % to 15 volume %, and even more preferably 7 volume % to 12 volume %.

[0168] The film formation temperature (the temperature of the transparent substrate film 2 when the primer layer 5 is formed) is, for example, -50.0°C to 30.0°C, preferably -30.0°C to 20.0°C, more preferably -20.0°C to 10.0°C, and even more preferably -15.0°C to 0.0°C.

[0169] The pressure inside the film formation chamber (pressure inside the film formation 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 still more preferably 0.15 Pa to 0.30 Pa.

[0170] Examples of power sources for applying voltage to the target include DC power sources, AC power sources, MF power sources, and RF power sources. MF power sources and AC power sources may be used in combination. A preferred power source is an MFAC power source.

[0171] The horizontal magnetic field strength above the target is, for example, 10 mT to 100 mT.

[0172] In this manner, the primer layer 5 is formed on one surface of the transparent substrate film 2 in the thickness direction.

[0173] <Anti-reflection layer formation process> Specifically, in the antireflection layer forming step, an alternating laminate made of niobium oxide layers 31 and silicon oxide layers 32 is formed by sputtering on one surface in the thickness direction of the primer layer 5. In other words, the niobium oxide layers 31 and the silicon oxide layers 32 are sputtered layers.

[0174] The sputtering method uses a sputtering deposition apparatus Z, such as the one described above, which can perform the film formation process using a roll-to-roll method. When a roll-to-roll sputtering deposition apparatus is used in the antireflection layer formation process, a transparent substrate film 2 with a primer layer 5 as a workpiece film W is run from a delivery roll to a take-up roll provided in the apparatus, while materials for the alternating laminate (specifically, niobium and silicon) are sequentially deposited on one thickness-wise surface of the primer layer 5 to form an alternating laminate. The running speed of the workpiece film W (transparent substrate film 2 with primer layer 5) is, for example, 0.5 to 10.0 m / min. The antireflection layer formation process uses a magnet unit 75 included in the second magnetron plasma unit 64 shown in FIG. 6. 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.

[0175] By forming the silicon oxide layer 32, which is the layer in the antireflection layer 3 closest to the antifouling layer 4, by a sputtering method with a sputtering angle of 35 degrees or less, the proportion of the structure having symmetric Si-O-Si stretching can be increased relative to the structure having asymmetric Si-O-Si stretching. Specifically, as a result, an antireflection film with excellent scratch resistance can be produced.

[0176] In the sputtering method used in the anti-reflection layer formation process, a sputtering deposition device equipped with multiple deposition chambers (R1 to R4) arranged in sequence along the travel path of the workpiece film W (transparent substrate film 2 with primer layer 5) as shown in Figure 3 is used to form the first to fourth layers in sequence.

[0177] Specifically, in the sputtering method, a sputtering gas (inert gas) is introduced into a deposition chamber of a sputter deposition apparatus under vacuum conditions, while a negative voltage is applied to a target placed on the outer periphery of a rotary target in the deposition chamber. This generates a glow discharge, ionizing the gas atoms, causing these gas ions to collide with the target surface at high speed, ejecting target material from the target surface, which is then deposited in the thickness direction. The target materials for the first and third layers are niobium or niobium suboxide (NbO X , X<2.5) is used, and in the second and fourth layers, silicon is used.

[0178] Examples of the sputtering gas include argon, krypton, xenon, and mixtures thereof, and argon is preferred.

[0179] In forming the antireflection layer 3, the sputtering method is preferably a reactive sputtering method. In the reactive sputtering method, for example, oxygen as a reactive gas is introduced into the film formation chamber in addition to the sputtering gas. That is, the antireflection layer 3 is formed in the presence of an inert gas and oxygen gas.

[0180] Specifically, in forming the first and third layers by reactive sputtering, the volume ratio of oxygen gas to the total volume of sputtering gas and oxygen gas (reactive gas) introduced into the film formation chamber is, for example, 0.5 to 20% by volume, preferably 1 to 10% by volume, more preferably 2 to 8% by volume, and even more preferably 3 to 6% by volume.

[0181] Furthermore, in forming the second and fourth layers by reactive sputtering, the amount of oxygen gas introduced is controlled using impedance control or PEM control (plasma emission monitoring control) so that the layers can be formed in a transition region between the metal region and the oxide region. That is, the silicon oxide layer 32, which is the layer closest to the antifouling layer, is formed by reactive sputtering, and in forming the silicon oxide layer 32, which is the layer closest to the antifouling layer by reactive sputtering, oxygen gas is introduced using impedance control or PEM control so that the layer can be formed in the transition region between the metal region and the oxide region.

[0182] In reactive sputtering, the film formation state can be roughly divided into a metal region, a transition region, and an oxide region depending on the proportion of reactive gas in all introduced gases (sputtering gas and reactive gas) during film formation. In the metal region, the proportion of oxygen gas (reactive gas) is low, and the film formation rate remains constant even if the proportion of oxygen gas changes slightly. In the oxide region, the proportion of oxygen gas is high, and the film formation rate remains constant even if the proportion of oxygen gas changes slightly. On the other hand, in the transition region, the proportion of oxygen gas is intermediate between the metal region and the oxide region, and a slight change in the proportion of oxygen gas significantly changes the film formation rate. In other words, while films can be formed at a stable rate in the metal region and oxide region, the film formation rate fluctuates in the transition region even with a slight change in the proportion of oxygen gas. Therefore, to form a film in the transition region, it is necessary to control the amount of oxygen gas introduced.

[0183] Methods for controlling the amount of oxygen gas introduced to reach the transition region include, for example, an impedance control method, in which the amount of oxygen gas introduced is controlled so that the plasma impedance is constant, i.e., the discharge voltage is constant, and a PEM control method, in which the plasma emission intensity of the discharge is detected and the amount of oxygen gas introduced into the film formation chamber is controlled.

[0184] By controlling the oxygen content to fall within the transition region, the second and fourth layers can be deposited at a high voltage and the deposition rate can be improved. As a result, the proportion of the structure having symmetric Si-O-Si stretching relative to the structure having asymmetric Si-O-Si stretching can be increased in the silicon oxide layer 32 in the antireflection layer 3, which is the layer closest to the antifouling layer 4.

[0185] The pressure inside the film formation chamber (the pressure inside the film formation chamber when the sputtering gas and / or oxygen is introduced) is, for example, 0.01 Pa to 5.0 Pa, preferably 0.05 Pa to 3.0 Pa, more preferably 0.10 Pa to 1.0 Pa, and still more preferably 0.15 Pa to 0.80 Pa.

[0186] The ultimate vacuum level in the film formation chamber before sputtering, the film formation temperature (the temperature of the transparent substrate film 2 when each layer is formed), the power supply for applying voltage to the target, and the horizontal magnetic field strength above the target are the same as those in the primer layer formation process described above.

[0187] In this manner, the antireflection layer 3 is formed on one surface of the primer layer 5 in the thickness direction.

[0188] <Anti-fouling layer formation process> Specifically, in the antifouling layer forming step, the antifouling layer 4 is formed by a dry coating method on one surface in the thickness direction of the antireflection layer 3. Examples of dry coating methods include vacuum deposition, sputtering, and CVD, with vacuum deposition being preferred. That is, the antifouling layer 4 is preferably a vapor-deposited film (layer).

[0189] In the vacuum deposition method, the material for the antifouling layer 4 described above was dried and solidified and used as a deposition source.

[0190] The deposition temperature is, for example, 150°C to 500°C, or preferably 200°C to 300°C.

[0191] In this manner, the antifouling layer 4 is formed on one surface of the antireflection layer 3 in the thickness direction.

[0192] In this manner, an anti-reflection film is produced.

[0193] (Action and effect) The above anti-reflection film 1 has a peak at 1050 cm in the difference spectrum calculated by Fourier transform infrared spectrophotometer analysis (FT-IR analysis). -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 When the absorption peak intensity resulting from the Si-O-Si asymmetric stretching is defined as X, 1 / X is 3.5 or more. Therefore, the ratio of the structure having the Si-O-Si symmetric stretching to the structure having the Si-O-Si asymmetric stretching is high, and the abrasion resistance is excellent.

[0194] In the method for producing the antireflection film 1, the silicon oxide layer 32, which is the layer in the antireflection layer 3 closest to the antifouling layer 4, is formed by sputtering at a sputtering angle of 35 degrees or less. This makes it possible to produce an antireflection film 1 with excellent scratch resistance.

[0195] 3. Variations <Modifications of anti-reflection film> In FIG. 1, the antireflection layer 3 is an alternate laminate made up of a niobium oxide layer 31a, a silicon oxide layer 32a, a niobium oxide layer 31b, and a silicon oxide layer 32b, but is not limited to this.

[0196] That is, the antireflection layer 3 is an alternating laminate composed of at least one niobium oxide layer 31 and at least one silicon oxide layer 32, and is not particularly limited as long as the layer in the antireflection layer 3 closest to the antifouling layer 4 is the silicon oxide layer 32. Specifically, the number of layers and the order of layers in the antireflection layer 3 are not particularly limited.

[0197] That is, the antireflection layer 3 may be, for example, an alternating laminate consisting of one niobium oxide layer 31 and one silicon oxide layer 32, or may be an alternating laminate consisting of three or more niobium oxide layers 31 and three or more silicon oxide layers 32.

[0198] <Modification of the manufacturing method of the anti-reflection film> In the method for producing the antireflection film 1 shown in FIGS. 2A to 2E, the primer layer 5 is formed, but the method is not limited to this.

[0199] That is, the method for producing the antireflection film 1 is not particularly limited as long as the antireflection layer 3 is formed by sputtering on one side in the thickness direction of the transparent substrate film 2. Specifically, the method does not need to include the step of forming a primer layer.

[0200] In addition, in the manufacturing method of the antireflection film 1 shown in Figures 2A to 2E, in the antireflection layer formation process, all of the layers, i.e., the niobium oxide layer 31a, the silicon oxide layer 32a, the niobium oxide layer 31b, and the silicon oxide layer 32b, are formed using the magnet unit 75 of the second magnetron plasma unit 64 shown in Figure 6, but this is not limited to this.

[0201] That is, in the antireflection layer forming process, there is no particular limitation as long as the silicon oxide layer 32, which is the layer in the antireflection layer 3 closest to the antifouling layer 4, is formed using the magnet unit 75 of the second magnetron plasma unit 64 shown in Figure 6.

[0202] More specifically, in the above-described method for manufacturing the antireflection film 1, the silicon oxide layers 32 other than the niobium oxide layer 31 and the silicon oxide layer 32 closest to the antifouling layer 4 as the antireflection layer 3 may be formed using the magnet unit 75 of the first magnetron plasma unit 64 shown in FIG. 5 . [Example]

[0203] The present invention will be described in more detail below with reference to examples, comparative examples, and reference examples. It should be noted that the present invention is not limited to the examples, comparative examples, and reference examples. The specific numerical values ​​of the blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the upper limit (a numerical value defined as "equal to or less than") or lower limit (a numerical value defined as "equal to or more than" or "exceeding") of the corresponding blending ratios (content ratios), physical property values, parameters, etc. described in the above "Modes for Carrying Out the Invention."

[0204] Example 1 <Preparation of anti-reflection film> An anti-reflection film was prepared as follows.

[0205] [Preparation of transparent substrate film] A cured resin layer-forming composition with a solids concentration of 42% was prepared by mixing 83 parts by weight of a nanosilica particle-containing acrylic monomer composition (product name: NC035HS, solids concentration: 60% by weight, manufactured by Arakawa Chemical Industries, Ltd.), 17 parts by weight of a UV-curable multifunctional urethane acrylate (product name: Beamset 580, solids concentration: 70% by weight, manufactured by Arakawa Chemical Industries, Ltd.), 1.5 parts by weight of a photopolymerization initiator (product name: OMNIRAD127D, manufactured by IGM Resins), 0.15 parts by weight of a leveling agent (product name: LE303, solids concentration: 40% by weight, manufactured by Kyoeisha Chemical Co., Ltd.), and butyl acetate. This cured resin layer-forming composition was applied to one side of an 80 μm-thick triacetylcellulose film (product name: Fujitack, manufactured by Fujifilm) in the thickness direction to a thickness of 5 μm after drying and dried at 80°C for 3 minutes. Then, a high-pressure mercury lamp was used, with an integrated light intensity of 200 mJ / cm 2 The coating layer was cured by irradiating it with ultraviolet light of 1000 W at 1000 W to form a cured resin layer. In this way, a transparent substrate film having a cured resin layer on the transparent resin film was obtained.

[0206] [Primer layer formation] First, one surface in the thickness direction of the transparent substrate film (one surface in the thickness direction of the cured resin layer) was plasma treated. For the plasma treatment, a roll-to-roll sputtering deposition apparatus Z (magnetron sputtering deposition apparatus Z) as shown in Figure 3 was used. The sputtering deposition apparatus Z is equipped with a deposition chamber in which the deposition process can be carried out while the work film (transparent substrate film) is running by the roll-to-roll method. The ultimate vacuum in the deposition chamber of the sputtering deposition apparatus was 1.0 x 10 -4 After evacuating the chamber to a vacuum of 0.5 Pa, argon was introduced into the film-forming chamber as a sputtering gas (inert gas), the pressure in the film-forming chamber was set to 0.5 Pa, the discharge power was set to 0.15 kW, and one surface in the thickness direction of the cured resin layer was plasma-treated while the transparent substrate film was being transported.

[0207] Next, a 4 nm thick ITO layer (primer layer) was formed on one thickness-wise surface of the transparent substrate film (one thickness-wise surface of the cured resin layer) by reactive sputtering. To form the primer layer, a roll-to-roll sputtering deposition apparatus Z (magnetron sputtering deposition apparatus Z) as shown in FIG. 3 was used. The sputtering deposition apparatus Z is equipped with a deposition chamber in which the deposition process can be carried out while running the workpiece film (transparent substrate film) using the roll-to-roll method. The sputtering deposition apparatus Z also includes a magnet unit 75 of the first magnetron plasma unit 64 shown in FIG. 5. Details of the magnet unit and sputtering deposition conditions used to form the primer layer are shown below.

[0208] The magnet unit used first to fourth magnetic pole parts, each with a length L of 13 mm between the opposite sides and the fixed side of 13 mm, and a separation distance D between the opposite sides and the fixed side of 13 mm. The second and third magnetic pole parts were north poles, and the first and fourth magnetic pole parts were south poles. The magnetization directions of the second and third magnetic pole parts were perpendicular to the width direction of the fixed member, and the magnetization directions of the first and fourth magnetic pole parts were parallel to the width direction of the fixed member. This configuration allows the magnet unit 75 of the first magnetron plasma unit 64 shown in FIG. 5 to have a sputtering angle (angle θ) of approximately 42 degrees.

[0209] The ultimate vacuum level in the deposition chamber of the sputter deposition equipment is 1.0 x 10 -4 After evacuating the chamber to a vacuum of 0.2 Pa, argon as a sputtering gas and oxygen as a reactive gas were introduced into the chamber, and the pressure inside the chamber was set to 0.2 Pa. The argon gas and oxygen gas were introduced into the chamber so that the volume ratio between them was 100:10. The target of the sputtering film formation apparatus was a sintered body of indium oxide and tin oxide, containing indium oxide and tin oxide in a mass ratio of 90:10. An MFAC power supply was used as the power source for applying voltage to the target, with a discharge power of 4.3 kW and a film formation temperature (the temperature of the transparent substrate film on which the primer layer is formed) of -8°C.

[0210] In this way, a primer layer was formed on one surface in the thickness direction of the transparent substrate film (one surface in the thickness direction of the cured resin layer).

[0211] [Formation of anti-reflection layer] Next, a sputtering method was used to form an alternating laminate (anti-reflection layer) on one thickness-wise surface of the primer layer. The laminate included a 16 nm-thick niobium oxide layer (first layer), a 38 nm-thick silicon oxide layer (second layer), a 30 nm-thick niobium oxide layer (third layer), and a 98 nm-thick silicon oxide layer (fourth layer), arranged in that order toward one thickness-wise direction. To form the anti-reflection layer, a roll-to-roll magnetron sputtering deposition apparatus Z, as shown in Figure 3, was used. The sputtering deposition apparatus Z includes a deposition chamber capable of performing the deposition process while running a workpiece film (a transparent substrate film with a primer layer) using the roll-to-roll method. The sputtering deposition apparatus Z also includes a magnet unit 75 in the second magnetron plasma unit 64, as shown in Figure 6. The magnet unit and sputtering deposition conditions used to form the anti-reflection layer are described below in detail.

[0212] The magnet unit used first to fourth magnetic poles, each with a length L of 10 mm between opposite sides and a distance D between the opposite sides and the fixed side of 20 mm. The second and third magnetic poles were N poles, and the first and fourth magnetic poles were S poles. The magnetization directions of the second and third magnetic poles were inclined in the thickness and width directions of the fixed member and intersected each other toward the center of the film-forming roll, while the magnetization directions of the first and fourth magnetic poles were parallel to the width direction of the fixed member. This configuration allows the magnet unit 75 of the second magnetron plasma unit 64 shown in FIG. 6 to have a sputtering angle (angle θ) of approximately 30 degrees.

[0213] In the deposition of the first layer, the ultimate vacuum in the deposition chamber of the sputtering deposition equipment was 1.0 × 10 -4 After evacuating the chamber to a vacuum of 0.5 Pa, argon as a sputtering gas (inert gas) and oxygen as a reactive gas were introduced into the chamber, and the pressure inside the chamber was set to 0.5 Pa. The argon gas and oxygen gas were introduced into the chamber at a volume ratio of 100:5. Niobium was used as the target of the sputtering film formation device. An MFAC power supply was used as the power source for applying voltage to the target, with a discharge power of 13 kW and a film formation temperature (the temperature of the transparent substrate film with a primer layer on which an anti-reflection layer was formed) of -8°C.

[0214] In the deposition of the second layer, the ultimate vacuum in the deposition chamber of the sputtering deposition equipment was 1.0 × 10 -4 After evacuating the chamber to a vacuum of 0.2 Pa, argon was introduced as a sputtering gas (inert gas) into the film-forming chamber, and the pressure inside the film-forming chamber was set to 0.2 Pa. The flow rate of oxygen gas, a reactive gas, was controlled using an impedance control method so that the film was formed in the transition region. Silicon was used as the target of the sputtering film-forming device. An MFAC power supply was used as the power source for applying voltage to the target, with a discharge power of 25 kW and a film-forming temperature (the temperature of the transparent substrate film with a primer layer on which the anti-reflection layer was formed) of -8°C.

[0215] The third layer was formed under the same conditions as those for the first layer described above.

[0216] The fourth layer was formed under the same conditions as those for the second layer described above.

[0217] In this way, an alternating laminate (anti-reflection layer) was formed on one thickness-wise surface of the primer layer, having 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) arranged in that order toward one thickness-wise side.

[0218] [Formation of anti-fouling layer] Thereafter, a 6 nm thick antifouling layer was formed by vacuum deposition on one surface of the antireflection layer in the thickness direction (one surface of the silicon oxide layer (fourth layer) in the thickness direction). The material for the antifouling layer was a dried antifouling layer composition (product name: KY1903-1, active ingredient: alkoxysilane compound containing a perfluoropolyether skeleton, manufactured by Shin-Etsu Chemical Co., Ltd.) used as a deposition source, and the heating temperature of the deposition source was 260°C.

[0219] In this way, an antifouling layer was formed on one surface in the thickness direction of the antireflection layer (one surface in the thickness direction of the silicon oxide layer (fourth layer)).

[0220] In this manner, an anti-reflection film was formed.

[0221] Example 2 The antireflection film of Example 2 was produced in the same manner as the antireflection film of Example 1, except that an alternating laminate (antireflection layer) having a 5-nm-thick niobium oxide layer (first layer) and a 130-nm-thick silicon oxide layer (second layer) arranged in this order toward one side in the thickness direction was formed on one surface in the thickness direction of the primer layer. That is, in Example 2, the third and fourth layers were not formed in the antireflection layer, and an antifouling layer was formed on one surface in the thickness direction of the antireflection layer (one surface in the thickness direction of the silicon oxide layer (second layer)).

[0222] Comparative Example 1 The antireflection film of Comparative Example 1 was produced in the same manner as the antireflection film of Example 1, except that the magnet unit 75 of the first magnetron plasma unit 64 shown in Figure 5, which was the same as that used to form the primer layer, was used to form the antireflection layer.

[0223] <Evaluation> [FT-IR analysis] Antireflection films of each example and comparative example were prepared, as well as sample films in which the antifouling layer and antireflection layer were removed from the antireflection films of each example and comparative example. An infrared absorption spectrum S1 was measured from one side in the thickness direction of each antireflection film, and an infrared absorption spectrum S2 was measured from one side in the thickness direction of each sample film, using an attenuated total reflection (ATR) method with a Fourier transform infrared spectrophotometer (FT-IR) (product name: Frontier, manufactured by PerkinElmer Japan). The measurements were performed at an incident angle of 45 degrees and 256 cumulative measurements, using a Ge prism.

[0224] The sample films were obtained by etching the antifouling layer and the antireflection layer of the antireflection film from each of the Examples and Comparative Examples according to the following procedure.

[0225] Specifically, the anti-reflection films of each Example and Comparative Example were set on a sample stage and subjected to solid nebulizer ICP-MS measurement. Using a decomposition device (Jupiter, manufactured by ST Japan), a femtosecond laser was irradiated onto the surface of the anti-reflection film (the surface of the anti-fouling layer side of the anti-reflection film), and the anti-fouling layer and the anti-reflection layer were etched by ablation. Compared to the silicon oxide layer, the niobium oxide layer tended to be more difficult to ablate. If part of the transparent substrate film is removed by etching, the 1000 cm wavelength laser beam was used. -1 Because the infrared absorption spectrum S2 in the excess region is affected, the etching process was stopped at the region where Nb element was detected but Si element was not detected using a measurement device (product name: iCAP TQ, manufactured by Thermo Fisher Scientific). -1Even if a small amount remains, it can be detected at a wavelength of 1000 cm -1 The infrared absorption spectrum measurement in the excess region is not affected. In this way, the sample film was obtained. Note that the influence of the ITO layer acting as a primer layer on the sample film can be ignored because the difference spectrum between the infrared absorption spectrum S1 and the infrared absorption spectrum S2 is calculated.

[0226] The infrared absorption spectrum S1 of the obtained anti-reflection film and the infrared absorption spectrum S2 of the sample film were measured at 1730 cm -1 The spectra were normalized by the peak derived from the C=O stretching vibration of the acrylate ester near 1050 cm. The difference spectrum was then obtained by subtracting the infrared absorption spectrum S2 from the infrared absorption spectrum S1. -1 The maximum absorption peak intensity due to the Si-O-Si symmetric stretching near 1200 cm is normalized to 1. -1 The absorption peak intensity due to the Si-O-Si asymmetric stretching was taken as X, and 1 / X was calculated. The results are shown in Table 1. A large 1 / X indicates a high ratio of structures with Si-O-Si symmetric stretching to structures with Si-O-Si asymmetric stretching.

[0227] [Indentation modulus] The 10 nm indentation modulus of the antireflection films of each example and comparative example was measured using a nanoindenter (product name: Tribo Indenter, manufactured by Hysitron). Specifically, a Berkovich (triangular pyramid) indenter was used to measure a single indentation from one thickness-wise surface of each antireflection film (one thickness-wise surface of the antifouling layer) to an indentation depth of 10 nm. The results are shown in Table 1. Note that, in an antireflection film, if the 10 nm indentation modulus of one thickness-wise surface of the antifouling layer is high, the film will have excellent abrasion resistance when sliding with steel wool or the like.

[0228] [Scratch resistance] The anti-reflection films of each example and comparative example were attached to a glass substrate using a 15 μm thick adhesive to prepare a measurement sample. Next, using a heavy-duty liner abraser (product name: Taber 5800, manufactured by Taber), steel wool #0000 was attached to a 10 mm diameter metal jig using an adhesive. The measurement sample was placed so that the anti-reflection film was in contact with the steel wool, and the steel wool was slid. The sliding conditions were a load of 500 g, a test speed of 60 cycles / min, and a stroke of 60 mm, and the sample was slid back and forth 5,000 times. The presence or absence of scratches was then confirmed under a three-wavelength fluorescent lamp and evaluated according to the following criteria. The results are shown in Table 1. {standard} A: No scratches B: Scratches have occurred

[0229] [Reflectance] The antireflection films of each example and comparative example were attached to a black acrylic plate using a 15 μm thick adhesive to prepare measurement samples. Using the measurement samples, the reflectance of each antireflection film was measured using an ultraviolet-visible-infrared spectrophotometer (product name: UH-4150, manufactured by Hitachi High-Tech Science Corporation). Measurements were made at wavelengths of 380 nm to 780 nm. The results are shown in Table 1.

[0230] [Table 1] [Explanation of symbols]

[0231] 1. Anti-reflective film 2. Transparent substrate film 3 Anti-reflection 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. a transparent substrate film, an anti-reflection layer, and an anti-fouling layer in this order toward one side in a thickness direction; the transparent substrate film comprises a transparent resin film, the antireflection layer is an alternating laminate including at least one niobium oxide layer and at least one silicon oxide layer; the layer of the antireflection layer closest to the antifouling layer is a silicon oxide layer; In the difference spectrum calculated by the following Fourier transform infrared spectrophotometer analysis (FT-IR analysis), －１ The maximum absorption peak intensity due to the Si-O-Si symmetric stretching around 1200 cm was normalized to 1. －１ The antireflection film has a 1 / X ratio of 5.0 or more, where X is the absorption peak intensity resulting from the asymmetric Si-O-Si stretching. (FT-IR analysis) An infrared absorption spectrum S1 is measured from one side in the thickness direction of the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer. Also, an infrared absorption spectrum S2 is measured from one side in the thickness direction of a sample film obtained by removing the antireflection layer and the antifouling layer from the antireflection film by total reflection measurement using a Fourier transform infrared spectrophotometer, and a difference spectrum between the infrared absorption spectrum S1 and the infrared absorption spectrum S2 is calculated.

2. The anti-reflection film according to claim 1 , wherein the transparent substrate film further comprises a cured resin layer disposed on one side in a thickness direction of the transparent resin film.

3. a primer layer disposed between the transparent substrate film and the antireflection layer; The anti-reflective film according to claim 1 , wherein the primer layer is a metal oxide layer.

4. The antireflection film according to claim 1 , wherein the antifouling layer has a 10 nm indentation elastic modulus of 16 GPa or more on one surface in the thickness direction.

5. A method for producing the anti-reflection film according to any one of claims 1 to 4, forming the antireflection layer on one side of the transparent substrate film in a thickness direction by a sputtering method; a silicon oxide layer in the antireflection layer that is closest to the antifouling layer, formed by a sputtering method with a sputtering angle (angle θ) of 35 degrees or less, as determined by the following method. On the outer peripheral surface of the rotary target, the tangential component of the magnetic flux density is measured in one circumferential direction of the rotary target. The sputtering angle (angle θ) formed by the line segment connecting the point corresponding to the maximum tangential component of the magnetic flux density and the center of the rotary target, and the line segment connecting the point corresponding to the minimum tangential component of the magnetic flux density and the center is calculated.

6. the silicon oxide layer closest to the antifouling layer is formed by a reactive sputtering method; 6. The method for producing an anti-reflection film according to claim 5, wherein in the deposition of the silicon oxide layer closest to the antifouling layer by the reactive sputtering method, oxygen gas is introduced using an impedance control method or a PEM control method so that the silicon oxide layer is deposited in a transition region between a metal region and an oxide region.

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