Antireflection film

Abstract

To provide an antireflection film capable of obtaining good reflection suppressing effect while securing adhesion of an antireflection layer to a base material film.SOLUTION: An antireflection film X includes a base material film (10), an adhesion layer (21) on the base material film (10), and an antireflection layer (22) on the adhesion layer (21). The antireflection layer (22) includes a high-refractive-index layer (22a) in contact with the adhesion layer (21), and a low-refractive-index layer (22b) on the high-refractive-index layer (22a). Roughness Sa of a face (22A) of the antireflection layer (22) opposite to the base material film (10) is 4.5 nm or less. In a cross-sectional view of an antireflection film X in a thickness direction H, ratio (L2 / L1) of second interface length L2 at an interface between the high-refractive index layer (22a) and the low-refractive index layer (22b) to first interface length L1 at an interface between the base material film (10) and the adhesion layer (21) is 1.10 or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an anti-reflection film. [Background technology]

[0002] Anti-reflection films are known that are placed on the outer surface of the display screen of display devices such as liquid crystal displays and organic EL displays. The anti-reflection film suppresses reflection of external light and glare of images on the display screen (anti-reflection properties). The anti-reflection film includes, for example, an anti-reflection layer made of an inorganic oxide and a resin substrate film that supports the layer. Such an anti-reflection film is described, for example, in Patent Document 1 listed below. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-65437 Summary of the Invention [Problem to be solved by the invention]

[0004] The antireflection film described in Patent Document 1 comprises a substrate film, an adhesive layer, and an antireflection layer in this order in the thickness direction. The substrate film has a hard coat (HC) layer on the adhesive layer side. This HC layer contains silica particles. As a result, the HC layer has surface irregularities on the adhesive layer side. The anchor effect of the surface irregularities of the HC layer and the physicochemical action of the adhesive layer enhance the adhesion of the antireflection layer to the substrate film. If the adhesion of the antireflection layer to the substrate film is insufficient, the antireflection layer will peel off from the substrate film.

[0005] However, in the antireflection film of Patent Document 1, the surface of the antireflection layer (the surface opposite to the substrate film) also has surface irregularities that follow the surface irregularities of the HC layer. The surface irregularities of the antireflection layer scatter a portion of the light incident on the antireflection film. The silica particles in the HC layer also scatter a portion of the light incident on the antireflection film. In an antireflection film, the more the incident light is scattered, the lower the antireflection properties become.

[0006] The present invention provides an antireflection film that can provide a good antireflection effect while ensuring the adhesion of the antireflection layer to the substrate film. [Means for solving the problem]

[0007] The present invention [1] provides an antireflection film comprising a substrate film, an adhesive layer on the substrate film, and an antireflection layer on the adhesive layer, wherein the antireflection layer comprises a high refractive index layer in contact with the adhesive layer and a low refractive index layer on the high refractive index layer, the surface of the antireflection layer opposite to the substrate film having a surface roughness Sa of 4.5 nm or less, and the ratio of a second interface length at the interface between the high refractive index layer and the low refractive index layer to a first interface length at the interface between the substrate film and the adhesive layer in a cross-sectional view in the thickness direction of the antireflection film is 1.10 or more.

[0008] The present invention [2] includes the anti-reflection film according to the above [1], in which the ratio is 2.00 or less.

[0009] The present invention [3] includes the antireflection film according to the above [1] or [2], wherein the total reflectance of light irradiated on the antireflection layer side from a standard illuminant D65 at a wavelength of 380 nm to 780 nm is 0.40% or less.

[0010] The present invention [4] is 100 g / m 2 The anti-reflection film according to any one of [1] to [3] above has a moisture permeability of 24 hours or more.

[0011] The present invention [5] includes the antireflection film according to any one of the above [1] to [4], in which the peeling rate of the antireflection layer in the following second test after the following first test is less than 20%.

[0012] First test: First, the substrate film side of the antireflection film is fixed to a glass plate, and then the antireflection layer of the antireflection film on the glass plate is irradiated with light at a temperature of 85°C, a relative humidity of 45%, and an irradiation intensity (integrated illuminance at 290 nm to 450 nm) of 150 mW / cm. 2 The light was irradiated for 32.5 hours under the above conditions.

[0013] Second test: First, eleven parallel first incisions (2 mm apart) extending linearly in a first direction and eleven parallel second incisions (2 mm apart) extending linearly in a second direction perpendicular to the first direction are formed in the anti-reflection layer and the adhesive layer of the anti-reflection film on the glass plate using a cutter knife, forming 100 grids. Next, isopropyl alcohol is continuously dripped onto the 100 grid areas of the anti-reflection film at a rate of 2 mL / min, while a polyester wiper is slid over the wiper contact surface of 20 mm x 20 mm, with a load of 1.5 kg / 20 mm, a sliding speed of 50 mm / sec, and 1000 reciprocations. Next, 1 mm of the 100 grids are removed. 2 The number of squares where the above peeling occurred is counted, and then the counted number is divided by 100 to calculate the peeling rate (%). [Effects of the Invention]

[0014] In the antireflection film of the present invention, as described above, the surface roughness Sa of the antireflection layer on the surface opposite to the substrate film is 4.5 nm or less, and in a cross-sectional view in the thickness direction, the ratio of the second interface length at the interface between the high refractive index layer and the low refractive index layer to the first interface length at the interface between the substrate film and the adhesive layer is 1.10 or more. In such an antireflection film, since the surface roughness Sa of the antireflection layer is 4.5 nm or less, scattering of light incident on the antireflection film at the surface of the antireflection layer can be suppressed. Since the antireflection layer is formed on the substrate film via the adhesive layer, and the ratio of the first and second interface lengths is 1.10 or more, adhesion of the antireflection layer to the substrate film can be ensured. Therefore, the antireflection film of the present invention can obtain a good reflection suppression effect while ensuring adhesion of the antireflection layer to the substrate film. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view of an embodiment of an anti-reflection film of the present invention. [Figure 2] 2 shows an example of a method for producing the antireflection film shown in Fig. 1. Fig. 2A shows a cured resin layer forming step, Fig. 2B shows an adhesion layer forming step, and Fig. 2C shows an antireflection layer forming step. [Figure 3] FIG. 2 is a schematic diagram illustrating the configuration of an apparatus for carrying out a plasma treatment step and a film formation step in the example of the method for producing the antireflection film shown in FIG. [Figure 4] 4 is a perspective view showing the positional relationship between a low inductance antenna and a base film in the plasma processing chamber shown in FIG. 3. FIG. [Figure 5] 4 is a cross-sectional view showing the positional relationship between the low inductance antenna and the base film in the plasma processing chamber shown in FIG. 3. [Figure 6] 3 is a schematic diagram of an observation image of a cross section of a sample in Example 1. FIG. [Figure 7] 10 is a schematic diagram of an observation image of a cross section of a sample in Comparative Example 3. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] An antireflection film X according to one embodiment of the present invention comprises a base film 10, an adhesive layer 21, and an antireflection layer 22, in this order, in the thickness direction H. The antireflection film X extends in a direction (plane direction D) perpendicular to the thickness direction H. The antireflection film X is disposed on the outer surface of a display screen of a display device, for example. Specifically, the base film 10 side of the antireflection film X is bonded to the outer surface of the display device via a bonding material such as a transparent adhesive sheet. Examples of display devices include liquid crystal displays and organic EL displays. In such an antireflection film X, the antireflection layer 22 has a surface 22A on the side opposite to the base film 10.

[0017] In this embodiment, the base film 10 includes a resin film 11 and a cured resin layer 12, which are arranged in this order in the thickness direction H. In this embodiment, the resin film 11 and the cured resin layer 12 are in contact with each other. In the base film 10, the cured resin layer 12 forms a first surface 10a, and the resin film 11 forms a second surface 10b.

[0018] The resin film 11 is a component that ensures the strength of the anti-reflection film X. The resin film 11 is, for example, a flexible, transparent resin film. Examples of materials for the resin film 11 include polyester resin, polyolefin resin, cellulose resin, acrylic resin, polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, and polystyrene 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). These materials may be used alone or in combination of two or more. From the viewpoints of transparency and strength, the material for the resin film 11 is preferably at least one selected from the group consisting of polyester resin, polyolefin resin, and cellulose resin, and more preferably at least one selected from the group consisting of PET, COP, and TAC.

[0019] The thickness of the resin film 11 is preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, and is preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less. When the thickness of the resin film 11 is equal to or greater than the above-mentioned lower limit, the strength of the antireflection film X can be ensured. When the thickness of the resin film 11 is equal to or less than the above-mentioned upper limit, the handleability of the base film 10 in the roll-to-roll process described below can be ensured.

[0020] The total light transmittance (JIS K 7375:2008) of the resin film 11 is preferably 80% or more, more preferably 90% or more, and even more preferably 95% or more, and is, for example, 100% or less. When the total light transmittance of the resin film 11 is the above-mentioned lower limit or more, the antireflection film X can ensure good transparency.

[0021] The cured resin layer 12 is a functional layer containing a resin. Specifically, the cured resin layer 12 is a cured product of a curable resin composition containing a curable resin. An example of the functional layer is a hard coat layer. The hard coat layer is a layer that makes it difficult for scratches to form on the exposed surface (the upper surface in FIG. 1 ) of the antireflection layer 22.

[0022] 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. These curable resins may be used alone or in combination of two or more. From the viewpoint of ensuring the hardness of the cured resin layer 12, the curable resin is preferably at least one selected from the group consisting of acrylic urethane resin and acrylic resin.

[0023] Examples of the curable resin include ultraviolet-curable resins and thermosetting resins. The curable resin is preferably ultraviolet-curable resin. When the curable resin is ultraviolet-curable resin, the curable resin can be cured without high-temperature heating, which can improve the production efficiency of the antireflection film X.

[0024] The curable resin may also contain, for example, a reactive diluent as described in JP-A-2008-88309. Specifically, the resin may contain a polyfunctional (meth)acrylate.

[0025] When the substrate film 10 has a cured resin layer 12, it is preferable that the cured resin layer 12 contain fewer inorganic oxide particles. The fewer inorganic oxide particles in the cured resin layer 12, the more the scattering of light incident on the antireflection film X caused by particles in the substrate film 10 can be suppressed, and the manufacturing cost of the antireflection film X can be reduced. Examples of materials for inorganic oxide particles include silica, alumina, titania, zirconia, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. The content of inorganic oxide particles in the cured resin layer 12 is preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, even more preferably 1% by mass or less, still more preferably 0.5% by mass or less, even more preferably 0.2% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0.0% by mass.

[0026] The thickness of the cured resin layer 12 is preferably 1 μm or more, more preferably 3 μm or more, even more preferably 5 μm or more, and is preferably 30 μm or less, more preferably 25 μm or less, even more preferably 20 μm or less. When the thickness of the cured resin layer 12 is equal to or greater than the above-mentioned lower limit, the functionality of the cured resin layer 12 can be ensured. Specifically, when the cured resin layer 12 is a hard coat layer, the scratch resistance of the antireflection layer 22 can be ensured. When the thickness of the cured resin layer 12 is equal to or less than the above-mentioned upper limit, cracking of the cured resin layer 12 can be suppressed, and good transportability in a roll-to-roll process can be ensured.

[0027] The total light transmittance (JIS K 7375:2008) of the substrate film 10 is preferably 80% or more, more preferably 90% or more, and even more preferably 95% or more, and is, for example, 100% or less. When the total light transmittance of the substrate film 10 is the above-mentioned lower limit or more, the antireflection film X can ensure good transparency.

[0028] The surface roughness Sa (arithmetic mean height according to ISO 25178-2:2012) of the first surface 10a of the substrate film 10 is preferably 1.0 nm or more, more preferably 1.2 nm or more, even more preferably 1.3 nm or more, and is preferably 4.0 nm or less, more preferably 3.0 nm or less, even more preferably 2.5 nm or less. When the surface roughness Sa of the first surface 10a is equal to or greater than the above-mentioned lower limit, the fine irregularities on the first surface 10a act as an anchor for the adhesive layer 21, thereby improving the adhesion of the antireflection layer 22 to the substrate film 10 via the adhesive layer 21. Having the surface roughness Sa of the first surface 10a equal to or less than the above-mentioned upper limit is advantageous for suppressing a decrease in the scratch resistance of the surface 22A of the antireflection layer 22.

[0029] The first surface 10a is, for example, a surface that has been plasma-treated. The plasma treatment is preferably an inductively coupled plasma treatment using an oxygen-containing gas (oxygen-LAICP treatment) generated by applying high-frequency power to a low-inductance antenna. The oxygen-LAICP treatment of the first surface 10a will be specifically described later in relation to the manufacturing method of the antireflection film X.

[0030] The adhesion layer 21 is disposed on one surface of the base film 10 in the thickness direction H. Specifically, the adhesion layer 21 is disposed on the first surface 10a of the base film 10. The adhesion layer 21 is in contact with the base film 10. The adhesion layer 21 is a layer that enhances the adhesion of the antireflection layer 22 to the base film 10. Examples of materials for the adhesion layer 21 include metals such as silicon, indium, nickel, chromium, aluminum, tin, gold, silver, platinum, zinc, titanium, tungsten, zirconium, palladium, and niobium, alloys of two or more of these metals, and oxides of these metals. From the viewpoint of achieving both adhesion to both the base film 10 and the antireflection layer 22 and transparency of the adhesion layer 21, indium tin oxide (ITO) or silicon oxide (SiOx) is preferred as the material for the adhesion layer 21. The silicon oxide used as the material of the adhesive layer 21 is preferably SiOx having a smaller amount of oxygen than the stoichiometric composition, and more preferably SiOx where x is 1.2 or more and 1.95 or less.

[0031] The thickness of the adhesion layer 21 is preferably 1 nm or more, more preferably 2 nm or more, and even more preferably 3 nm or more, and is preferably 10 nm or less, more preferably 7 nm or less, and even more preferably 5 nm or less. When the thickness of the adhesion layer 21 is equal to or greater than the above-mentioned lower limit, the adhesion between the substrate film 10 and the antireflection layer 22 can be ensured. When the thickness of the adhesion layer 21 is equal to or less than the above-mentioned upper limit, the transparency of the adhesion layer 21 can be ensured.

[0032] The antireflection layer 22 is disposed on one surface of the adhesive layer 21 in the thickness direction H. The antireflection layer 22 is in contact with the adhesive layer 21. The antireflection layer 22 is a layer that suppresses the reflection intensity of external light (antireflection properties).

[0033] In this embodiment, the antireflection layer 22 includes a high-refractive index layer 22a, a low-refractive index layer 22b, a high-refractive index layer 22c, a low-refractive index layer 22d, and an antifouling surface layer 22e, in this order from the adhesive layer 21 side in the thickness direction H. The antireflection layer 22 of this embodiment is an antireflection layer with an antifouling surface layer. The high-refractive index layer 22a is in contact with the adhesive layer 21. The high-refractive index layer 22a is in contact with the low-refractive index layer 22b. The low-refractive index layer 22b is in contact with the high-refractive index layer 22c. The high-refractive index layer 22c is in contact with the low-refractive index layer 22d. The high-refractive index layers 22a and 22c have relatively high refractive indexes, and the low-refractive index layers 22b and 22d have relatively low refractive indexes. In the antireflection layer 22, for example, the intensity of reflected light is attenuated by interference between reflected light at multiple interfaces in the high-refractive index layers 22a and 22c and the low-refractive index layers 22b and 22d. Such interference can be achieved by adjusting the optical film thickness (product of the refractive index and thickness of the film) of each layer of the antireflection layer 22.

[0034] The high refractive index layer 22a (first high refractive index layer) is made of a high refractive index material having a refractive index of preferably 1.9 or more at a wavelength of 550 nm. Examples of high refractive index materials include niobium oxide (Nb2O5), titanium oxide, zirconium oxide, indium tin oxide (ITO), and antimony tin oxide (ATO). From the viewpoint of achieving both a high refractive index and low absorption of visible light, the high refractive index material is preferably niobium oxide (refractive index 2.33). The optical film thickness of the high refractive index layer 22a is, for example, 20 nm or more and, for example, 55 nm or less.

[0035] The low refractive index layer 22b (first low refractive index layer) is made of a low refractive index material having a refractive index of preferably 1.6 or less at a wavelength of 550 nm. Examples of low refractive index materials include silicon dioxide (SiO2) and magnesium fluoride. From the viewpoint of achieving both a low refractive index and low absorption of visible light, the low refractive index material is preferably silicon dioxide (refractive index 1.46). The optical film thickness of the low refractive index layer 22b is, for example, 15 nm or more and, for example, 70 nm or less.

[0036] The high-refractive-index layer 22c (second high-refractive-index layer) is made of a high-refractive-index material having a refractive index of preferably 1.9 or more at a wavelength of 550 nm. Examples of the high-refractive-index material include the materials described above for the high-refractive-index layer 22a, and niobium oxide is preferred. The optical thickness of the high-refractive-index layer 22c is, for example, 60 nm or more and, for example, 330 nm or less.

[0037] The low-refractive-index layer 22d (second low-refractive-index layer) is made of a low-refractive-index material having a refractive index of preferably 1.6 or less at a wavelength of 550 nm. Examples of the low-refractive-index material include the materials described above for the low-refractive-index layer 22b, with silicon dioxide being preferred. The optical thickness of the low-refractive-index layer 22d is, for example, 100 nm or more and, for example, 160 nm or less.

[0038] The total thickness of the antireflection layer 22, from the high-refractive-index layer 22a to the low-refractive-index layer 22d, is preferably 180 nm or more, more preferably 200 nm or more, and even more preferably 220 nm or more, and is preferably 320 nm or less, more preferably 280 nm or less, and even more preferably 250 nm or less. In this embodiment, the total thickness of the antireflection layer 22 is the sum of the thicknesses of the high-refractive-index layers 22a and 22c and the low-refractive-index layers 22b and 22d. When the total thickness of the antireflection layer 22 is equal to or greater than the above-mentioned lower limit, the antireflection layer 22 can ensure its function of attenuating the intensity of reflected light. When the total thickness of the antireflection layer 22 is equal to or less than the above-mentioned upper limit, cracking of the antireflection layer 22 can be suppressed.

[0039] The anti-fouling surface layer 22e is a layer having an anti-fouling function. The anti-fouling surface layer 22e is disposed on the low refractive index layer 22d. The anti-fouling function of the anti-fouling surface layer 22e includes a function of suppressing adhesion of contaminants such as hand oils to the exposed surface of the anti-reflection film X when it is in use, and a function of facilitating removal of adhered contaminants.

[0040] Examples of materials for the antifouling surface layer 22e include organic fluorine compounds. As the organic fluorine compound, an alkoxysilane compound having a perfluoropolyether group is preferably used. Examples of the alkoxysilane compound having a perfluoropolyether group include compounds represented by the following general formula (1):

[0041] R 1 -R 2 -X-(CH2) m -Si(OR 3 )3(1)

[0042] In general formula (1), R 1 represents a linear or branched fluorinated alkyl group (having, for example, 1 to 20 carbon atoms) in which one or more hydrogen atoms in the alkyl group have been substituted with fluorine atoms, and preferably represents a perfluoroalkyl group in which all hydrogen atoms in the alkyl group have been substituted with fluorine atoms.

[0043] R 2represents 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. Examples of the repeating unit of a PFPE group include a repeating unit of a linear PFPE group and a repeating unit of a branched PFPE group. Examples of the repeating unit of a linear PFPE group include -(OC n F 2n ) p (n represents an integer of 1 or more and 20 or less, and p represents an integer of 1 or more and 50 or less; the same applies hereinafter). Examples of the repeating structure of the branched PFPE group include a structure represented by -(OC(CF3)2) p - and -(OCF2CF(CF3)CF2) p The repeating structure of the PFPE group is preferably a repeating structure of a linear PFPE group, more preferably -(OCF2) p -and-(OC2F4) p - are some examples.

[0044] R 3 represents an alkyl group having 1 to 4 carbon atoms, and preferably represents a methyl group.

[0045] X represents an ether group, a carbonyl group, an amino group, or an amide group, and preferably represents an ether group.

[0046] m represents an integer of 1 or more, and preferably represents an integer of 20 or less, more preferably 10 or less, and even more preferably 5 or less.

[0047] Of such alkoxysilane compounds having a perfluoropolyether group, the compound represented by the following general formula (2) is preferably used.

[0048] CF3-(OCF2) q -(OC2F4) r -O-(CH2)3-Si(OCH3)3(2)

[0049] In the general formula (2), q represents an integer of 1 or more and 50 or less, and r represents an integer of 1 or more and 50 or less.

[0050] The alkoxysilane compounds having a perfluoropolyether group may be used alone or in combination of two or more kinds.

[0051] In this embodiment, the antifouling surface layer 22e is a film (dry coating film) formed by a dry coating method. Dry coating methods include sputtering, vacuum deposition, and CVD. The antifouling surface layer 22e is preferably a dry coating film, and more preferably a vacuum deposition film.

[0052] The antifouling surface layer 22e is made of a material containing an alkoxysilane compound having a perfluoropolyether group, and is a dry coating film (preferably a vacuum-deposited film), which is suitable for ensuring high adhesion of the antifouling surface layer 22e to the substrate and therefore suitable for ensuring peel resistance of the antifouling surface layer 22e. The high peel resistance of the antifouling surface layer 22e helps to maintain the antifouling function of the antifouling surface layer 22e.

[0053] From the viewpoint of ensuring the peel resistance of the antifouling surface layer 22e, the thickness of the antifouling surface layer 22e is preferably 1 nm or more, more preferably 3 nm or more, even more preferably 5 nm or more, particularly preferably 7 nm or more, and is preferably 25 nm or less, more preferably 20 nm or less, even more preferably 18 nm or less.

[0054] The antireflection layer 22 has a surface 22A (the surface of the antifouling surface layer 22e) on the side opposite the substrate film 10. The surface roughness Sa (arithmetic mean height according to ISO 25178-2:2012) of the surface 22A is 4.5 nm or less, preferably 3.0 nm or less, more preferably 2.5 nm or less, even more preferably 2.0 nm or less, and even more preferably 1.8 nm or less. When the surface roughness Sa of the surface 22A is equal to or less than the above upper limit, light scattering at the surface 22A can be suppressed. Furthermore, the surface roughness Sa of the surface 22A is preferably 1.0 nm or more, more preferably 1.3 nm or more, even more preferably 1.5 nm or more, even more preferably more than 1.5 nm, and even more preferably 1.6 nm or more. Having the surface roughness Sa of the surface 22A equal to or greater than the above lower limit is advantageous for reducing frictional force and ensuring good slipperiness at the surface 22A. The method for measuring the surface roughness Sa is as described below in the examples.

[0055] In a cross-sectional view of the antireflection film X in the thickness direction H, the interface between the base film 10 and the adhesive layer 21 has fine irregularities (not shown). The interface between two adjacent layers in the antireflection layer 22 also has fine irregularities (not shown). The microscopic irregularities are, for example, irregularities on the order of nanometers. In a cross-sectional view of the antireflection film X in the thickness direction H, the ratio (L2 / L1) of the second interface length L2 at the interface (second interface) between the high refractive index layer 22a and the low refractive index layer 22b to the first interface length L1 at the interface (first interface) between the base film 10 and the adhesive layer 21 is 1.10 or more, preferably 1.15 or more, more preferably 1.17 or more, and even more preferably 1.20 or more. The first interface length L1 is the length of the first interface included in a predetermined range in the plane direction D in one cross-sectional view. The second interface length L2 is the length of the second interface included in the same range in the plane direction D in the same cross-sectional view. The method for measuring the first interface length L1 and the second interface length L2 is as described below in the Examples. When the ratio (L2 / L1) is equal to or greater than the above-mentioned lower limit, the adhesion of the antireflection layer 22 in the antireflection film X can be improved by the anchor effect. Furthermore, the ratio (L2 / L1) is preferably 2.00 or less, more preferably 1.50 or less, and even more preferably 1.30 or less. When the ratio (L2 / L1) is equal to or less than the above-mentioned upper limit, the surface roughness Sa of the surface 22A of the antireflection layer 22 can be reduced, thereby suppressing light scattering at the surface 22A. Examples of methods for adjusting the ratio (L2 / L1) include adjusting the conditions for plasma treatment of the first surface 10a of the substrate film 10 and adding an appropriate amount of particles to the cured resin layer 12.

[0056] The total reflectance of light irradiated from a standard illuminant D65 at a wavelength of 380 nm to 780 nm on the antireflection layer 22 side of the antireflection film X is preferably 0.40% or less, more preferably 0.36% or less, even more preferably 0.33% or less, and is, for example, 0.00% or more. When the total reflectance of the antireflection film X is equal to or less than the above upper limit, the antireflection properties of the antireflection film X can be ensured. This makes it possible to suppress reflection of external light and glare of images on the display screen on which the antireflection film X is disposed in a display device. The method for measuring the total reflectance is as described below in the examples.

[0057] The moisture permeability of the anti-reflection film X is preferably 100 g / m 2 24 hours or more, preferably 200g / m 2 24 hours or more, more preferably 300g / m 2 24 hours or more, more preferably 330 g / m 2 24 hours or more, and preferably 500 g / m 2 24 hours or less, preferably 400g / m 2 24 hours or less, more preferably 380 g / m 2 24 hours or less. The method for measuring the moisture permeability is as described below in the Examples. When the moisture permeability of the antireflection film X is equal to or greater than the above lower limit, moisture contained in the polarizer in the polarizing plate is easily released to the outside through the antireflection film X in a heated environment after the antireflection film X is attached to the polarizing plate, thereby suppressing moisture-induced deterioration of the polarizer. When the moisture permeability of the antireflection film X is equal to or less than the above upper limit, deterioration of the polarizing plate in a humid environment after the antireflection film X is attached to the polarizing plate can be suppressed. One method for adjusting the moisture permeability is, for example, adjusting the pressure (air pressure) in the film formation chamber during sputtering film formation, which will be described later.

[0058] The peeling rate of the antireflection layer 22 of the antireflection film X in the second test described below after the first test (accelerated weathering test) described below is preferably less than 20%, more preferably 15% or less, even more preferably 10% or less, and even more preferably less than 10%, from the viewpoint of ensuring the adhesion of the antireflection layer 22. The methods of the first and second tests are described more specifically below in the examples. When the peeling rate of the antireflection layer 22 is equal to or less than the above upper limit, it is possible to prevent the antireflection properties of the antireflection film X from deteriorating due to peeling of the antireflection layer 22 in practical use.

[0059] First test: First, the substrate film 10 side of the antireflection film X is fixed to a glass plate. Next, the antireflection layer 22 of the antireflection film X on the glass plate is irradiated with light at a temperature of 85°C, a relative humidity of 45%, and an irradiation intensity (integrated illuminance from 290 nm to 450 nm) of 150 mW / cm. 2 The light was irradiated for 32.5 hours under the above conditions.

[0060] Second test: First, eleven parallel first incisions (2 mm apart) extending linearly in a first direction and eleven parallel second incisions (2 mm apart) extending linearly in a second direction perpendicular to the first direction were made with a cutter knife in the anti-reflection layer 22 and adhesive layer 21 of the anti-reflection film X on the glass plate after the first test, forming 100 grids with the first and second incisions. Next, isopropyl alcohol was continuously dripped at 2 mL / min over the 100 grid areas of the anti-reflection film X, while a polyester wiper was slid over the wiper contact surface of 20 mm x 20 mm, with a load of 1.5 kg / 20 mm, a sliding speed of 50 mm / sec, and 1000 reciprocations. Next, 1 mm of the 100 grids were removed. 2 The number of squares where the above peeling occurred is counted, and then the count is divided by 100 to calculate the peeling rate (%).

[0061] As described above, in the antireflection film X, the surface roughness Sa of the surface 22A of the antireflection layer 22 is 4.5 nm or less, and in a cross-sectional view in the thickness direction H, the ratio (L2 / L1) of the second interface length L2 at the interface between the high refractive index layer 22a and the low refractive index layer 22b to the first interface length L1 at the interface between the base film 10 and the adhesive layer 21 is 1.10 or more. In such an antireflection film X, since the surface roughness Sa of the surface 22A is 4.5 nm or less, scattering of light incident on the antireflection film X at the surface 22A can be suppressed. The ratio (L2 / L1) of the first interface length L1 to the second interface length L2 of 1.10 or more can be achieved, for example, by roughening the surface of a base film (base film 10 in this embodiment) whose surface does not substantially contain particles, and then forming an antireflection layer on the surface via a predetermined adhesive layer. The antireflection layer 22 is formed on the substrate film 10 via the adhesive layer 21, and the ratio of the first and second interface lengths is 1.10 or more, thereby ensuring adhesion of the antireflection layer 22 to the substrate film 10. Furthermore, since the substrate film 10 does not contain particles, scattering of light incident on the antireflection film X due to particles in the substrate film 10 can be suppressed.

[0062] Such an antireflection film X ensures adhesion of the antireflection layer 22 to the substrate film 10, while providing a good antireflection effect.

[0063] 2A to 2C show an example of a method for producing the antireflection film X. This production method includes a cured resin layer forming step (FIG. 2A), a plasma treatment step, and a film forming step (FIGS. 2B and 2C).

[0064] In the cured resin layer forming step, as shown in FIG. 2A, a cured resin layer 12 is formed on a long resin film 11. This results in a substrate film 10. The cured resin layer 12 can be formed by applying the above-described curable resin composition to the resin film 11 to form a coating film, and then curing the coating film. The curable resin composition may contain other components besides the above-described curable resin, as necessary. Examples of other components include a solvent and a leveling agent. Examples of solvents include butyl acetate, ethyl acetate, toluene, and cyclopentanone. When the curable resin composition contains an ultraviolet-curable resin as the curable resin, the curable resin composition preferably contains a photopolymerization initiator. When the curable resin composition contains a thermosetting resin as the curable resin, the curable resin composition preferably contains a thermal polymerization initiator.

[0065] When the curable resin composition contains a solvent, the coating film on the resin film 11 is dried after the curable resin composition is applied. The drying temperature is, for example, 50° C. or higher and, for example, 120° C. or lower. The drying time is, for example, 10 seconds or longer and, for example, 10 minutes or shorter.

[0066] When the curable resin composition contains an ultraviolet-curable resin, the coating on the resin film 11 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 or more, and for example, 500 mJ / cm 2 The following is the result.

[0067] When the curable resin composition contains a thermosetting resin, the coating on the resin film 11 is cured by heating. The heating temperature is, for example, 100° C. or higher and, for example, 150° C. or lower. The heating time is, for example, 10 seconds or higher and, for example, 10 minutes or shorter.

[0068] In this manner, a long substrate film 10 can be produced. In this embodiment, a roll of the long substrate film 10 is prepared. Specifically, the substrate film 10 is wound so that the first surface 10a of the substrate film 10 faces inward in the radial direction of the roll.

[0069] In this manufacturing method, a plasma treatment process and a film formation process are then carried out sequentially while the base film 10 is transported as a workpiece film W by a roll-to-roll method under a reduced pressure atmosphere. The apparatus Y shown in Figure 3 is an example of an apparatus for carrying out the plasma treatment process and the film formation process. The apparatus Y includes a feed chamber R1, a winding chamber R2, a connecting chamber C1, a plasma treatment chamber C2, a connecting chamber C3, a film formation chamber C4 (first film formation chamber), a connecting chamber C5, and a film formation chamber C6 (second film formation chamber).

[0070] The unwinding chamber R1 is equipped with a unwinding roller 51 for unwinding the workpiece film W. A roll of a long base film 10 is attached to the unwinding roller 51 as the workpiece film W. In addition, a predetermined number of guide rollers G for guiding the workpiece film W are provided within the unwinding chamber R1.

[0071] The winding chamber R2 is equipped with a winding roller 52 for winding up the workpiece film W. A predetermined number of guide rollers G for guiding the workpiece film W are provided in the winding chamber R2.

[0072] The connecting chamber C1 is located next to the unwinding chamber R1 in the running direction of the workpiece film W and before the plasma processing chamber C2. A predetermined number of guide rollers G for guiding the workpiece film W are provided within the connecting chamber C1. The connecting chamber C1 is connected to a vacuum pump (not shown) and is configured to adjust the pressure within the chamber. When the device Y is in operation, the pressure within the connecting chamber C1 is maintained at a predetermined pressure between the pressure within the unwinding chamber R1 and the pressure within the plasma processing chamber C2. This ensures a pressure difference between the unwinding chamber R1 and the plasma processing chamber C2.

[0073] The plasma processing chamber C2 is located between the connecting chamber C1 and the connecting chamber C3 in the running direction of the workpiece film W. The plasma processing step is carried out in the plasma processing chamber C2, as will be described later. A first line L1 equipped with a flow control valve for introducing gas into the chamber is connected to the plasma processing chamber C2.

[0074] In this embodiment, the plasma processing chamber C2 is equipped with a plurality of low inductance antennas (LA) 71. A low inductance antenna means an antenna that has a low inductance of 7.5 μH or less and can generate inductively coupled plasma by applying high frequency power. In this embodiment, the LA71 is supported by a mounting fixture 72 and covered by a cover block 73 (not shown in FIG. 4) and is placed inside the plasma processing chamber C2 as shown in FIGS. 4 and 5 (an example in which the number of LA71 is four is shown).

[0075] The multiple LAs 71 are aligned in the running direction of the base film 10 and in a direction perpendicular to the running direction (the width direction of the base film 10). The fixture 72 is a vacuum flange. As shown in FIG. 5, the LAs 71 are fixed to the fixture 72 via feedthroughs 74. As shown in FIG. 4, the fixture 72 is attached to an opening 75 provided in the wall of the plasma processing chamber C2. Specifically, the fixture 72 is attached to the opening 75 with a seal member (not shown) sandwiched between the wall of the plasma processing chamber C2 and the fixture 72. The LAs 71 are electrically connected to a high-frequency power source (RF power source) outside the plasma processing chamber C2 via an impedance matching box. The LAs 71 are formed of a conductor. Examples of conductors include copper and silver, with copper being preferred. The LAs 71 may be covered with an insulator. Examples of insulators include glass and quartz.

[0076] The cover block 73 includes a block body 73A and multiple partition plates 73B. The block body 73A has multiple storage spaces 73a. Each storage space 73a stores one LA 71. The partition plates 73B are arranged to close the storage spaces 73a. The storage spaces 73a are sealed spaces. In the cover block 73, the block body 73A is made of, for example, aluminum. Examples of aluminum include aluminum A5052. The partition plates 73B are made of an insulating material. Examples of insulating materials include quartz and glass. The separation distance d' (shown in FIG. 5) between the base film 10 traveling in the plasma processing chamber C2 and the cover block 73 is, for example, 50 to 200 mm. Such a cover block 73 helps to avoid damage and contamination of the LA71 due to plasma processing without excessively reducing the plasma conversion efficiency due to the power applied to the LA71, and also helps to suppress damage to the substrate film 10 being plasma processed.

[0077] As shown in FIG. 4, in this embodiment, the LA71 has an open loop shape. Having the LA71 have an open loop shape is advantageous for reducing the inductance of the LA71. Therefore, the open loop LA71 can suppress an increase in voltage due to an increase in power applied to the LA71. This suppresses abnormal discharge during plasma processing, as described below. Suppressing abnormal discharge can suppress damage to the base film 10 being plasma processed. Specifically, the LA71 has a U-shape with two free ends. For each LA71, the two free ends are fixed to the fixture 72 so as to be aligned in the width direction of the base film 10. In this embodiment, the LA 71 has an extension 71a on the side opposite to the two free ends. The extension 71a extends parallel to the base film 10 passing through the plasma processing chamber C2. The extension 71a extends in the width direction of the base film 10. Each extension 71a may extend in the running direction of the base film 10 (four LAs 71 may be arranged in this manner). The length of the extension 71a is, for example, 50 to 150 mm (FIG. 4 exemplarily illustrates a case where the length of the extension 71a is the same as the maximum length d2 of the LA 71, which will be described later). The LA 71 may have a coil shape instead of an open loop shape.

[0078] The LA 71 extends from the fixture 72 toward the base film 10. The LA 71 preferably extends perpendicular to the fixture 72. The extension length d1 of the LA 71 from the fixture 72 is, for example, 30 to 150 mm. The maximum length d2 of the LA 71 in the surface direction of the base film 10 is, for example, 50 to 150 mm. The separation distance d3 (shown in FIG. 5) between the LA 71 and the base film 10 is, for example, 50 to 200 mm. The extension length d1 and the separation distance d3 are preferably the same. The ratio (d3 / d1) of the separation distance d3 to the extension length d1 is, for example, 0.5 to 3.5. The number (number of rows) of the LA 71 spaced apart in the running direction of the base film 10 may be 1, 2, or 3, or may be 4 or more if necessary, depending on the running speed of the base film 10 (i.e., the plasma treatment time). The center-to-center distance d4 between adjacent LAs 71 in the running direction of the base film 10 is, for example, 100 to 500 mm. The center-to-center distance d5 between adjacent LAs 71 in the width direction of the base film 10 is, for example, 200 to 500 mm. Adjusting the center-to-center distance d5 allows for control of the uniformity of the plasma density (described below) in the width direction of the base film 10. The center-to-center distance d4 and the center-to-center distance d5 are preferably the same. The ratio of the center-to-center distance d5 to the center-to-center distance d4 (d5 / d4) is, for example, 0.5 to 2.0. The centers of the extensions 71a of the four LAs 71 preferably form a square with the vertices at their vertices. Such a set of LAs 71 can generate high-density plasma. For example, the high-frequency antenna for plasma generation described in JP 2013-258153 A may be used as the LAs 71.

[0079] In this embodiment, the plasma processing chamber C2 further includes a transport roller 53. The transport roller 53 is a main guide roller for transporting the workpiece film W within the plasma processing chamber C2. The transport roller 53 has a temperature adjustment function that allows the workpiece film W to be heated or cooled. In other words, the transport roller 53 is a transport roller with a temperature adjustment function. When the apparatus Y is in operation, the transport roller 53 transports the base film 10 while contacting the second surface 10b of the base film 10. The LA71 is disposed opposite the transport roller 53. With the apparatus Y equipped with such a plasma treatment chamber C2, in the plasma treatment step S2, the transport roller 53 with a temperature control function that contacts the base film 10 can perform plasma treatment on the base film 10 while cooling or heating the base film 10. Controlling the temperature of the base film 10 can suppress thermal deformation of the base film 10 and also suppress the effect of the thermal deformation on the transport of the base film 10.

[0080] The connecting chamber C3 is located next to the plasma processing chamber C2 in the running direction of the workpiece film W and before the film forming chamber C4. A predetermined number of guide rollers G for guiding the workpiece film W are provided inside the connecting chamber C3. The connecting chamber C3 is connected to a vacuum pump (not shown) and is configured to adjust the pressure inside the chamber. When the device Y is in operation, the pressure inside the connecting chamber C3 is maintained at a predetermined pressure between the pressure inside the plasma processing chamber C2 and the pressure inside the film forming chamber C4. This ensures a pressure difference between the plasma processing chamber C2 and the film forming chamber C4.

[0081] The film-forming chamber C4 is disposed next to the connecting chamber C3 in the running direction of the workpiece film W. The film-forming chamber C4 is also connected to a vacuum pump (not shown) so that the chamber can be adjusted to a predetermined vacuum level. In the film-forming chamber C4, the film-forming process for the high-refractive index layer 22a to the low-refractive index layer 22d is carried out, as will be described later.

[0082] In this embodiment, the film formation chamber C4 is a sputtering film formation chamber. The film formation chamber C4 includes a film formation roller 54 and multiple sputtering chambers 60 (sputtering chambers 60a to 60e) (five sputtering chambers 60 are illustrated as an example). The film formation roller 54 is a main guide roller for transporting the workpiece film W within the film formation chamber C4. The film formation roller 54 has a temperature control function that allows the workpiece film W to be heated or cooled. The sputtering chamber 60 is a partitioned space within the film formation chamber C4. The multiple sputtering chambers 60 are arranged along the circumferential direction of the film formation roller 54. Each sputtering chamber 60 opens toward the film formation roller 54. A cathode 61 is provided within the sputtering chamber 60. A target (not shown) is arranged on the cathode 61 as a film formation material supply material. The target is arranged on the target so as to face the film formation roller 54. Each sputtering chamber 60 is provided with a power supply (not shown) for applying a voltage to the target to generate a glow discharge. Examples of power supplies include DC power supplies, AC power supplies, MF power supplies, RF power supplies, and MF-AC power supplies. MF-AC power supplies refer to AC power supplies with a frequency band of several kHz to several MHz. Each sputtering chamber 60 is connected to a required number of second lines (not shown) equipped with flow rate control valves for introducing gas into the chamber. In addition, a predetermined number of guide rollers G for guiding the workpiece film W are provided in the film formation chamber C4.

[0083] The connecting chamber C5 is disposed between the connecting chamber C4 and the film forming chamber C6 in the running direction of the workpiece film W. A predetermined number of guide rollers G for guiding the workpiece film W are provided in the connecting chamber C5.

[0084] The film-forming chamber C6 is disposed between the connection chamber C5 and the winding chamber R2 in the running direction of the workpiece film W. In this embodiment, the film-forming chamber C6 is a vacuum deposition chamber. The film-forming chamber C6 includes a material holding section 62 and a deposition amount adjustment valve (not shown) whose opening is controllable. The film-forming chamber C6 is connected to a vacuum pump (not shown) so that the pressure inside the chamber can be adjusted. The film-forming chamber C6 is provided with a predetermined number of guide rollers G for guiding the workpiece film W. In the film-forming chamber C6, the film-forming step of the stain-resistant surface layer 22e is carried out.

[0085] A film-forming material supply (not shown) is arranged in the material holding unit 62 so as to face the workpiece film W being transported within the film-forming chamber C6. The material holding unit 62 may be provided with a built-in resistance heating means, a built-in high-frequency induction heating means, or an electron beam heating means as a means for heating the film-forming material supply.

[0086] The plasma processing step and the film forming step are carried out in sequence by the above-described apparatus Y. Specifically, the steps are as follows.

[0087] The workpiece film W is unwound from the unwinding chamber R1. After being unwound from the unwinding chamber R1, the workpiece film W passes through the connecting chamber C1, the plasma processing chamber C2, the connecting chamber C3, the film forming chamber C4, the connecting chamber C5, and the film forming chamber C6 in sequence, and is then wound up in the winding chamber R2. The running speed of the workpiece film W is, for example, 0.5 m / min or more, and, for example, 5 m / min or less. Furthermore, the entire line from the unwinding chamber R1 to the winding chamber R2 is not open to the atmosphere along the way, and the process is carried out in this line under a reduced pressure atmosphere. The reduced pressure atmosphere is preferably under vacuum. Under vacuum preferably means a reduced pressure atmosphere of 7 Pa or less.

[0088] A plasma treatment process is carried out in the plasma treatment chamber C2. In the plasma treatment process, the first surface 10a of the substrate film 10 is plasma-treated in a reduced pressure atmosphere in the plasma treatment chamber C2 (chamber). In this embodiment, the plasma treatment is a treatment using inductively coupled plasma of an oxygen-containing gas (oxygen-LAICP treatment) generated by applying high-frequency power to the LA71. Specifically, the process is as follows.

[0089] During plasma treatment, oxygen is supplied into the plasma treatment chamber C2 via the first line L1. In addition to oxygen, an inert gas may be supplied into the plasma treatment chamber C2. Examples of inert gases include argon, krypton, and xenon. The gas in the plasma treatment chamber C2 may contain gases other than the inert gas. Examples of other gases include oxygen, nitrogen, hydrogen, and water vapor. The oxygen concentration of the gas (oxygen-containing gas) in the plasma treatment chamber C2 is preferably 30% by volume or more, more preferably 50% by volume or more, even more preferably 80% by volume or more, even more preferably 90% by volume or more, even more preferably 95% by volume or more, and particularly preferably 100% by volume. When the oxygen concentration is equal to or greater than the lower limit, high-density oxygen plasma can be generated. This is useful for forming nanometer-order micro-roughness on the first surface 10a of the substrate film 10 and for purifying and highly activating the first surface 10a.

[0090] The pressure (first pressure) within the plasma processing chamber C2 during plasma processing is preferably 0.1 Pa or more, more preferably 0.2 Pa or more, even more preferably 0.3 Pa or more, and preferably 7 Pa or less, more preferably 5 Pa or less, and even more preferably 3 Pa or less. When the first pressure is equal to or greater than the above-mentioned lower limit, a plasma environment of sufficient density for surface modification of the first surface 10a of the substrate film 10 can be formed within the plasma processing chamber C2. When the first pressure is equal to or less than the above-mentioned upper limit, thermal damage to the first surface 10a caused by excessively high-density plasma can be suppressed during plasma processing, and excessive roughening of the first surface 10a can be suppressed. Suppressing excessive roughening helps to prevent a decrease in the mechanical strength of the first surface 10a. The first pressure can be adjusted by the amount of oxygen gas supplied into the plasma processing chamber C2.

[0091] The frequency of the high-frequency power applied to the LA71 during plasma processing is preferably 1 MHz or higher, more preferably 5 MHz or higher, even more preferably 10 MHz or higher, and preferably 100 MHz or lower, more preferably 80 MHz or lower, and even more preferably 60 MHz or lower. When the frequency is equal to or higher than the lower limit, plasma current density can be increased and plasma discharge can be stabilized during plasma processing. When the frequency is equal to or lower than the upper limit, the antenna potential can be suppressed, thereby suppressing damage to the substrate film 10 caused by the plasma. Furthermore, the high-frequency power is preferably 0.1 kW or higher, more preferably 0.3 kW or higher, even more preferably 1.0 kW or higher, and preferably 10 kW or lower, more preferably 8 kW or lower, and even more preferably 6 kW or lower. When the high-frequency power is equal to or higher than the lower limit, a high-density plasma environment can be formed in the plasma processing chamber C2 during inductively coupled plasma processing. When the high-frequency power is equal to or lower than the upper limit, excessive damage to the substrate caused by the plasma can be suppressed.

[0092] In the plasma treatment step, the plasma current density at the intermediate position between the LA71 and the substrate film 10 is preferably 1.0 mA / cm 3 More preferably, 2.0 mA / cm 3 More preferably, 3.0 mA / cm 3 or more, and preferably 10 mA / cm 3 Less than or equal to 8 mA / cm 3 Less than 4 mA / cm, more preferably 3 The inductively coupled plasma processing using a low inductance antenna can achieve a higher plasma current density (for example, a plasma density about 100 times higher) than the capacitively coupled plasma processing. When the plasma current density is equal to or greater than the lower limit, sufficient plasma oxygen particles can be secured in the plasma treatment chamber C2 during the plasma treatment, thereby enabling appropriate surface modification of the first surface 10a of the substrate film 10. When the plasma current density is equal to or less than the upper limit, damage to the first surface 10a caused by excessively high density plasma oxygen particles can be suppressed during the plasma treatment. The plasma current density can be adjusted by, for example, adjusting the amount of oxygen gas introduced into the plasma processing chamber C2, adjusting the frequency of the high frequency power in the high frequency power supply, and adjusting the magnitude of the applied power.

[0093] In the film formation step, first, in the film formation chamber C4, following the plasma treatment step, an adhesive layer 21 and an inorganic layer 22 are formed in sequence on the first surface 10a of the substrate film 10 by sputtering in a reduced pressure atmosphere. The reduced pressure atmosphere is preferably a vacuum.

[0094] In the sputtering method, a sputtering gas (inert gas) is introduced into each sputtering chamber 60 via a second line, while a negative voltage is applied to a target (film forming material) placed on a cathode 61 in the sputtering chamber 60. This generates a glow discharge, ionizing the gas atoms, causing the gas ions to collide with the target surface at high speed, ejecting the target material from the target surface and depositing the ejected target material on the workpiece film W. Examples of sputtering gases include argon, krypton, and xenon.

[0095] When the film forming material is a metal oxide, the sputtering method may be a reactive sputtering method. In the reactive sputtering method, oxygen (reactive gas) is introduced into the sputtering chamber 60 in addition to the sputtering gas. The oxygen is introduced into the sputtering chamber 60 through another second line. In the reactive sputtering method, the target is made of, for example, a metal in the metal oxide that forms each layer.

[0096] In the sputtering method, the pressure (second pressure) inside the sputtering chamber 60 is, for example, 0.1 to 5.0 Pa depending on the type of layer to be formed. The film formation temperature (the temperature of the workpiece film W adjusted by the film formation roller 54) is, for example, -10°C to 150°C.

[0097] In the film formation process, first, an adhesive layer 21 is formed on the substrate film 10 by sputtering in the sputtering chamber 60a. When an ITO layer is formed as the adhesive layer 21, an ITO target is used as the target placed on the cathode 61 in the sputtering chamber 60a. Then, reactive sputtering is performed while introducing argon and oxygen into the sputtering chamber 60a (reactive sputtering is similarly performed in the following sputtering methods in the sputtering chambers 60b to 60e).

[0098] Next, a high refractive index layer 22a is formed by sputtering in the sputtering chamber 60b on the adhesion layer 21. When forming an NbO layer as the high refractive index layer 22a, an Nb target is used as the target placed on the cathode 61 in the sputtering chamber 60b.

[0099] Next, a low refractive index layer 22b is formed on the high refractive index layer 22a by sputtering in the sputtering chamber 60c. When forming an SiO2 layer as the low refractive index layer 22b, a Si target is used as the target placed on the cathode 61 in the sputtering chamber 60c.

[0100] Next, a high refractive index layer 22c is formed on the low refractive index layer 22b by sputtering in the sputtering chamber 60d. When forming a NbO layer as the high refractive index layer 22c, a Nb target is used as the target placed on the cathode 61 in the sputtering chamber 60d.

[0101] Next, a low refractive index layer 22d is formed on the high refractive index layer 22c by sputtering in the sputtering chamber 60e. When forming an SiO2 layer as the low refractive index layer 22d, a Si target is used as the target placed on the cathode 61 in the sputtering chamber 60e.

[0102] In the film formation process, the antifouling surface layer 22e is further formed in the film formation chamber C6. In this step, the antifouling surface layer 22e is formed on the low refractive index layer 22d of the workpiece film W by vacuum deposition, which is a dry coating method, in the film formation chamber C6. Specifically, with the pressure inside the film formation chamber C6 reduced to a vacuum by operating a vacuum pump, a film formation material supply (not shown) placed in the material holding section 62 is heated to a predetermined temperature, and the vacuum deposition method is performed.

[0103] In the device Y, after the plasma treatment step and the film forming step, the anti-reflection film X as the workpiece film W reaches the winding chamber R2 and is wound up by the winding roller 52.

[0104] In this manner, a long antireflection film X can be produced.

[0105] The antireflection layer 22 of the antireflection film X does not have to include the above-mentioned antifouling surface layer 22e. In that case, the surface of the low refractive index layer 22d opposite to the substrate film 10 becomes the surface 22A of the antireflection layer 22. An antireflection film X not including the antifouling surface layer 22e can be produced by omitting the step in the film-forming chamber C6 in the above-mentioned production process of the antireflection film X. [Example]

[0106] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples. The specific numerical values ​​of the blending amounts (contents), physical property values, parameters, etc. described below can be substituted for the upper limits (numerical values ​​defined as "equal to or less than") or lower limits (numerical values ​​defined as "equal to or more than") of the corresponding blending amounts (contents), physical property values, parameters, etc. described in the above-mentioned "Description of the Invention."

[0107] Example 1 The anti-reflection film of Example 1 was produced by carrying out the following steps in order.

[0108] First, a hard coat layer was formed on one side of a triacetyl cellulose (TAC) film as a resin film to prepare a substrate film (preparation step). Specifically, 100 parts by mass (solid content equivalent) of a butyl acetate solution of ultraviolet-curable acrylic urethane resin (product name "Luxidia 17-806", solid content concentration 80% by mass, manufactured by DIC Corporation) was mixed with 5 parts by mass of a photopolymerization initiator (product name "IRGACURE 906", manufactured by BASF), and 0.01 parts by mass of a leveling agent (product name "GRANDIC PC4100", manufactured by DIC Corporation) to obtain a mixed solution. Next, a mixed solvent of cyclopentanone (CPN) and propylene glycol monomethyl ether (PGM) (mass ratio of CPN to PGM: 45:55) was added to adjust the solid content of the mixed solution to 36% by mass. This produced a first resin composition. On the other hand, a long TAC film (product name "KC4UY", thickness 40 μm, manufactured by Konica Minolta Advanced Layer) was prepared. Next, the first resin composition was applied to one side of the TAC film to form a coating film. Next, this coating film was dried by heating and then cured by ultraviolet irradiation. As a result, a hard coat (HC) layer with a thickness of 7 μm was formed on the TAC film. The heating temperature was 90°C, and the heating time was 1 minute. For ultraviolet irradiation, a high-pressure mercury lamp was used as the light source, and ultraviolet rays with a wavelength of 365 nm were irradiated onto the coating film, with an integrated irradiation dose of 300 mJ / cm. 2 In this manner, a TAC film with an HC layer was prepared as a substrate film.

[0109] Next, a plasma treatment process and a subsequent film-forming process were performed on the substrate film while the substrate film was transported in a vacuum using a roll-to-roll method (roll-to-roll process). For the plasma treatment and film-forming processes, an apparatus (first apparatus) capable of performing roll-to-roll processes on a workpiece film was used. The first apparatus includes a feed chamber, a plasma treatment chamber (first plasma treatment), a first film-forming chamber, a second film-forming chamber, and a take-up chamber. The feed chamber, plasma treatment chamber, first film-forming chamber, second film-forming chamber, and take-up chamber are arranged in this order and are interconnected. The feed chamber includes a feed roller. A roll of the above-mentioned substrate film was set on the feed roller as the workpiece film. The plasma treatment chamber includes a temperature-controlled transport roller (transport roller 53 in FIG. 3) and four low-inductance antennas (LA71 in FIG. 4 and FIG. 5) covered by cover blocks (cover block 73 in FIG. 5), as shown in FIG. 4 and FIG. 5. Each low-inductance antenna has an extension (extension 71a in FIG. 4) parallel to the base film. The four low-inductance antennas have an extension length d1 of 88 mm, a maximum length d2 (length of the extension) of 100 mm, a separation distance d3 of 112 mm, a center-to-center distance d4 of 290 mm, and a center-to-center distance d5 of 280 mm (FIGS. 4 and 5). Each low-inductance antenna is electrically connected to a high-frequency power source (RF power source, frequency 13.56 MHz) via an impedance matcher outside the plasma processing chamber. The separation distance d' between the base film traveling within the plasma processing chamber and the cover block is 100 mm. The first film-forming chamber is a sputtering chamber and includes a film-forming roller (film-forming roller 54 in FIG. 3) and first to fifth sputtering chambers (sputtering chambers 60a to 60e in FIG. 3). Each sputtering chamber is a partitioned space within the first film-forming chamber. The first to fifth sputtering chambers are arranged in this order along the circumferential direction of the film-forming roller and in the running direction of the substrate film. Each sputtering chamber is equipped with a cathode arranged opposite the film-forming roller. Each sputtering chamber is connected to a required number of second lines (not shown) equipped with flow rate control valves for introducing gas into the chamber. The second film-forming chamber is a vacuum deposition chamber and is equipped with a material holding unit (material holding unit 62 in FIG. 3).The winding chamber includes a winding roller.

[0110] In the roll-to-roll process, the HC surface (first side) of the base film was plasma treated in the plasma treatment chamber (plasma treatment step). The running speed of the base film (film running speed) was 1.0 m / min. The temperature of the temperature-controlled transport roller was -8°C. The plasma treatment conditions were as follows:

[0111] The ultimate vacuum level of the plasma processing chamber is 1.0 x 10 -4 After evacuating the inside of the apparatus until the pressure reached 1.5 Pa, oxygen was introduced into the plasma processing chamber until the pressure inside the plasma processing chamber reached 1.5 Pa. A high-frequency power of 2 kW was applied to the four low-inductance antennas by a high-frequency power supply, and an inductively coupled plasma of an oxygen-containing gas was formed around the antennas (the HC layer surface of the substrate film was treated with this plasma). The plasma current density at the midpoint between the low-inductance antennas and the substrate film was 1.3 mA / cm. 3 It was. The plasma current density was measured by a Langmuir probe for plasma measurement.

[0112] In the first film-forming chamber, an adhesive layer, a first high-refractive index layer, a first low-refractive index layer, a second high-refractive index layer, and a second low-refractive index layer were sequentially formed on the plasma-treated substrate film. Specifically, while the substrate film was cooled and transported by the film-forming roll in the first film-forming chamber, an adhesive layer was formed on the HC layer of the substrate film in the first sputtering chamber, a first high-refractive index layer was formed on the adhesive layer in the second sputtering chamber, a first low-refractive index layer was formed on the first high-refractive index layer in the third sputtering chamber, a second high-refractive index layer was formed on the first low-refractive index layer in the fourth sputtering chamber, and a second low-refractive index layer was formed on the second high-refractive index layer in the fifth sputtering chamber. The film-forming temperature (temperature of the film-forming roll) was -8°C. More specifically, the processes are as follows.

[0113] In the first sputtering chamber, a 4 nm thick ITO layer was formed as an adhesion layer by reactive sputtering (adhesion layer formation step). In this step, the inside of the first film formation chamber was maintained at a vacuum of 1.0×10 -4 After the chamber was evacuated to a vacuum of 0.2 Pa, argon as an inert gas and oxygen as a reactive gas were introduced into the first sputtering chamber, and the pressure inside the first sputtering chamber was set to 0.2 Pa. The amount of oxygen introduced into the first sputtering chamber was 10 parts by volume per 100 parts by volume of argon introduced into the first sputtering chamber. A sintered body of indium oxide and tin oxide (ITO with a tin oxide concentration of 10 mass %) was used as the target. An MF-AC power supply was used as the power source for applying voltage to the target (the same applies to the second to fifth sputtering chambers described below). The discharge power was 4.3 kW.

[0114] In the second sputtering chamber, a 14 nm thick Nb2O5 layer (refractive index 2.33) was formed as the first high refractive index layer by reactive sputtering. In this process, after the first film formation chamber was evacuated as described above, argon as an inert gas and oxygen as a reactive gas were introduced into the second sputtering chamber, and the pressure in the second sputtering chamber was set to 0.5 Pa. The amount of oxygen introduced was 5 volume parts per 100 volume parts of argon introduced into the second sputtering chamber. A Nb target was used. The discharge power was 13 kW.

[0115] In the third sputtering chamber, a 28 nm thick SiO2 layer (refractive index 1.46) was formed as the first low refractive index layer by reactive sputtering. In this process, after the first film formation chamber was evacuated as described above, argon as an inert gas and oxygen as a reactive gas were introduced into the third sputtering chamber, and the pressure in the third sputtering chamber was set to 0.2 Pa. The amount of oxygen introduced per 100 volume parts of argon introduced into the third sputtering chamber was 30 volume parts. A Si target was used. The discharge power was 25 kW.

[0116] In the fourth sputtering chamber, a 105 nm thick Nb2O5 layer (refractive index 2.33) was formed as the second high refractive index layer by reactive sputtering. In this process, after the first film formation chamber was evacuated as described above, argon as an inert gas and oxygen as a reactive gas were introduced into the fourth sputtering chamber, and the pressure in the fourth sputtering chamber was set to 0.5 Pa. The amount of oxygen introduced into the fourth sputtering chamber was 13 parts by volume per 100 parts by volume of argon introduced into the fourth sputtering chamber. The target used was a Nb target, and the discharge power was set to 27.5 kW.

[0117] In the fifth sputtering chamber, a 84 nm thick SiO2 layer (refractive index 1.46) was formed as the second low refractive index layer by reactive sputtering. In this process, after the first film formation chamber was evacuated as described above, argon as an inert gas and oxygen as a reactive gas were introduced into the fifth sputtering chamber, and the pressure in the fifth sputtering chamber was set to 0.2 Pa. The amount of oxygen introduced per 100 volume parts of argon introduced into the fifth sputtering chamber was 30 volume parts. A Si target was used. The discharge power was 20.5 kW.

[0118] In the second film-forming chamber, an anti-fouling surface layer was formed on the second low-refractive index layer. Specifically, an 8-nm-thick anti-fouling surface layer was formed on the second low-refractive index layer by vacuum deposition using a perfluoropolyether group-containing alkoxysilane compound as the deposition source. The deposition source was a solid obtained by drying "OPTOOL UD509" manufactured by Daikin Industries, Ltd. (a perfluoropolyether group-containing alkoxysilane compound represented by the above general formula (2), solid content concentration 20% by mass). The heating temperature of the deposition source in the vacuum deposition method was 260°C.

[0119] As described above, the antireflection film of Example 1 was produced. The antireflection film of Example 1 comprises a substrate film with an HC layer, an adhesive layer on the HC layer, and an antireflection layer (first high refractive index layer / first low refractive index layer / second high refractive index layer / second low refractive index layer / antifouling surface layer) on the adhesive layer. The substrate film of the antireflection film of Example 1 has a plasma-treated HC layer surface. This plasma treatment is an inductively coupled plasma treatment using an oxygen-containing gas generated by applying high-frequency power to a low-inductance antenna (oxygen-LAICP treatment).

[0120] Example 2 The antireflection film of Example 2 was produced in the same manner as the antireflection film of Example 1, except for the following: In the preparation step, the following resin composition was used instead of the first resin composition to form an HC layer on the TAC film. Specifically, the following is the procedure.

[0121] In the preparation step, 80 parts by weight (solids equivalent) of a UV-curable acrylic urethane resin (product name "UT-7314" manufactured by Mitsubishi Chemical Corporation), 20 parts by weight (solids equivalent) of a multifunctional acrylate (product name "Viscoat #300" manufactured by Osaka Organic Chemical Industry Co., Ltd.) whose main component is pentaerythritol triacrylate, 1.5 parts by weight of a photopolymerization initiator (product name "Omnirad 127D" manufactured by BASF), and 0.06 parts by weight of a leveling agent (product name "Polyflow LE-303" manufactured by Kyoeisha Chemical Co., Ltd.) were mixed to obtain a mixed solution. Next, a mixed solvent of butyl acetate and cyclopentanone (CPN) (70:30 mass ratio of butyl acetate to CPN) was added to the mixed solution as a solvent to prepare a resin composition with a solids concentration of 40% by weight.

[0122] Comparative Example 1 The antireflection film of Comparative Example 1 was produced in the same manner as the antireflection film of Example 1, except for the following: In the plasma treatment step, argon was introduced into the plasma treatment chamber instead of oxygen, and the plasma treatment was carried out. This plasma treatment was an inductively coupled plasma treatment (Ar-LAICP treatment) using an argon-containing gas generated by applying high-frequency power to a low-inductance antenna.

[0123] Comparative Example 2 First, in the same manner as in the preparation step of Example 1, an HC layer was formed on one side of a TAC film to prepare a base film (TCA film / HC layer).

[0124] Next, a plasma treatment process and a subsequent film formation process were performed on the substrate film while the substrate film was transported in a vacuum using a roll-to-roll method (roll-to-roll process). A second device capable of performing roll-to-roll processes on workpiece films was used for the plasma treatment and film formation processes. The second device had the same configuration as the first device, except that it had a second plasma treatment chamber instead of the first plasma treatment chamber. The second plasma treatment chamber had a pair of flat electrodes for generating plasma: a cathode electrode and an anode electrode (both rectangular electrodes made of SUS304). The pair of flat electrodes were spaced 50 mm apart and arranged parallel to the substrate film passing through the second plasma treatment chamber. The anode electrode was located 35 mm away from the substrate film passing through the plasma treatment chamber and was grounded outside the plasma treatment chamber. The cathode electrode was positioned facing the HC layer surface of the substrate film and was electrically connected to a high-frequency power source (RF power source, 13.56 MHz) via an impedance matcher. The length of each electrode facing the base film in the running direction of the film is 110 mm, and the length in the width direction is 430 mm.

[0125] In the second plasma treatment chamber, the HC surface (first side) of the substrate film was subjected to plasma treatment (bombardment treatment). The running speed of the substrate film (film running speed) was 1.0 m / min. The plasma treatment conditions were as follows:

[0126] The ultimate vacuum of the second plasma processing chamber is 1.0 x 10 -4 After evacuating the chamber to a vacuum of 0.5 Pa, argon was introduced into the second plasma treatment chamber, and the pressure inside the plasma treatment chamber was set to 0.5 Pa. A capacitively coupled plasma (CCP) was generated by applying 500 W of power between the planar electrodes using a high-frequency power supply. In this plasma environment, the surface of the HC layer of the substrate film was bombarded with argon ions (Ar-BB treatment).

[0127] In the first film-forming chamber, layers from the adhesive layer to the second low refractive index layer were formed in order on the plasma-treated substrate film in the same manner as described above for Example 1. In the second film-forming chamber, an antifouling surface layer was formed on the second low refractive index layer in the same manner as described above for Example 1.

[0128] Comparative Example 3 The antireflection film of Comparative Example 3 was produced in the same manner as the antireflection film of Comparative Example 2, except for the following: In the preparation step, the second resin composition was used instead of the first resin composition to form an HC layer on the TAC film. Specifically, the procedure is as follows.

[0129] In the preparation step, 83 parts by weight (solids equivalent) of a nanosilica particle-containing acrylic monomer composition (product name "NC035HS," nanosilica concentration 60% by weight, manufactured by Arakawa Chemical Industries, Ltd.), 17 parts by weight (solids equivalent) 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 (solids equivalent) of a leveling agent (product name "LE303," solids concentration 40% by weight, manufactured by Kyoeisha Chemical Co., Ltd.), and butyl acetate were mixed to prepare a second resin composition with a solids concentration of 42% by weight. Meanwhile, a long TAC film (product name "KC4UY," thickness 40 μm, manufactured by Konica Minolta Advanced Layer) was prepared. Next, a second resin composition was applied to one side of the TAC film to form a coating film. Next, this coating film was dried by heating and then cured by ultraviolet irradiation. This resulted in a 7 μm thick HC layer being formed on the TAC film. The heating temperature was 90°C and the heating time was 1 minute. For ultraviolet irradiation, a high-pressure mercury lamp was used as the light source, and ultraviolet rays with a wavelength of 365 nm were irradiated onto the coating film, with an integrated irradiation dose of 300 mJ / cm. 2 In this way, a TAC film with an HC layer was produced as a substrate film. The HC layer of the substrate film in Comparative Example 3 contained 50 mass % of nanosilica particles.

[0130] <Surface roughness> The surface roughness of the antireflection layer surface was measured for each of the antireflection films of Example 1, Example 2, and Comparative Examples 1 to 3. Specifically, the surface roughness Sa (arithmetic mean height based on ISO 25178-2:2012) of the exposed surface of the antireflection layer in the antireflection film was measured in a 1 μm square image observed with an atomic force microscope (product name "Dimention Edge SPC-160113-01", manufactured by Bruker). In this measurement, the measurement mode was set to tapping mode, and an antimony-doped Si cantilever (product name "RTESP-300", manufactured by Bruker) was used as the probe. The measurement results are shown in Table 1.

[0131] <Total reflectance> The total reflectance of each of the antireflection films of Example 1, Example 2 and Comparative Examples 1 to 3 was measured as follows.

[0132] First, the side of the anti-reflection film opposite the anti-reflection layer was attached to a black acrylic plate (2 mm thick) using a specified transparent acrylic adhesive. This resulted in a laminated film. Next, a film strip for measurement was cut out from the laminated film. Next, the spectrum of total reflected light (including specular reflected light) was measured for the film strip using a spectrophotometer (product name "UH4150", manufactured by Hitachi High-Tech Science Corporation). For the measurement, standard illuminant D65 was used as the light source, and the film strip was placed in the spectrophotometer so that light was irradiated from the anti-reflection layer side of the film strip. The measurement was performed using the integrating sphere measurement mode of the spectrophotometer. The measured reflectance was the total reflectance (luminous reflectance) of light irradiated from standard illuminant D65 with wavelengths of 380 nm to 780 nm onto the anti-reflection layer side of the film strip (anti-reflection film). The measurement results are shown in Table 1.

[0133] <Moisture permeability> The moisture permeability in the thickness direction of each antireflection film of Example 1, Example 2, and Comparative Examples 1 to 3 was measured in accordance with JIS K7129:2008 Appendix B (infrared sensor method). The measurements were carried out in an atmosphere at a temperature of 40°C and a relative humidity of 90%. The measurement results are shown in Table 1.

[0134] <Interface length ratio> The ratio of the second interface length L2 between the high refractive index layer and the low refractive index layer to the first interface length L1 between the substrate film and the adhesive layer in a cross-sectional view was examined for each of the antireflection films of Example 1, Example 2, and Comparative Examples 1 to 3. Specifically, the ratio is as follows:

[0135] First, a sample for cross-sectional observation of the antireflection film was prepared by FIB microsampling. In the FIB microsampling, an FIB device (product name "FB2200", manufactured by Hitachi) was used, and an acceleration voltage was set to 10 kV. Next, the cross-section of the sample was observed by FE-TEM. For this observation, an FE-TEM device (product name "JEM-2800", manufactured by JEOL) was used, and an acceleration voltage was set to 200 kV. FIG. 6 shows a schematic image of the cross-section of the sample of Example 1. In the image of Example 1, the HC layer 12 of the base film 10, the adhesive layer 21, the high-refractive-index layer 22a as the first high-refractive-index layer, the low-refractive-index layer 22b as the first low-refractive-index layer, the high-refractive-index layer 22c as the second high-refractive-index layer, and the low-refractive-index layer 22d as the second low-refractive-index layer were observed. FIG. 7 shows a schematic image of the cross-section of the sample of Comparative Example 3. In the observation image of Comparative Example 3, the HC layer 12′, adhesive layer 21′, high-refractive index layer 22a′, low-refractive index layer 22b′, high-refractive index layer 22c′, and low-refractive index layer 22d′ of the base film 10′ were observed. The observation image was then analyzed using image processing software ImageJ. As a result, within an image width of 274 nm in the observation image (cross-sectional view), the first interface length L1 (thick line in FIGS. 6 and 7) of the interface between the base film 10 (10′) and adhesive layer 21 (21′) and the second interface length L2 (thick line in FIGS. 6 and 7) of the interface between the high-refractive index layer 22a (22a′) and low-refractive index layer 22b (22b′) were determined. The ratio (L2 / L1) of the second interface length L2 to the first interface length L1 was then calculated. The values ​​are shown in Table 1.

[0136] <Adhesion> The antireflection films of Examples 1 and 2 and Comparative Examples 1 to 3 were subjected to the following first and second tests to examine the adhesion of the antireflection layer.

[0137] First test: First, the substrate film side of the antireflection film was fixed to a glass plate. Next, the antireflection layer of the antireflection film on the glass plate was irradiated with light at a temperature of 85°C, a relative humidity of 45%, and an irradiation intensity (integrated illuminance from 290 nm to 450 nm) of 150 mW / cm. 2The test was carried out using Iwasaki Electric's "Eye Super UV Tester SUV-W161."

[0138] Second test: First, 11 parallel first incisions (2 mm apart) extending linearly in a first direction and 11 parallel second incisions (2 mm apart) extending linearly in a second direction perpendicular to the first direction were made with a cutter knife in the anti-reflection layer and adhesive layer of the anti-reflection film on the glass plate after the first test, forming 100 grids. Next, isopropyl alcohol was continuously dripped at 2 mL / min over the 100 grid areas of the anti-reflection film, while a polyester wiper (trade name "Anticon Gold", manufactured by Sanplatec Co., Ltd.) was slid over the wiper contact surface of 20 mm x 20 mm, with a load of 1.5 kg / 20 mm, a sliding speed of 50 mm / sec, and 1,000 reciprocations. Next, 1 mm of the 100 grids were removed. 2 The number of squares where the above peeling occurred was counted, and the counted number was then divided by 100 to calculate the peeling rate (%).

[0139] A peeling rate of less than 10% was evaluated as "excellent," a peeling rate of 10% or more but less than 20% was evaluated as "good," a peeling rate of 20% or more but less than 80% was evaluated as "poor," and a peeling rate of 80% or more was evaluated as "very poor." The results are shown in Table 1.

[0140] [evaluation] In the antireflection film of Comparative Example 1, the HC layer of the substrate film does not contain particles, so the substrate film surface does not have irregularities caused by particles. In addition, the plasma treatment in the manufacturing process of the antireflection film of Comparative Example 1 is, as described above, an inductively coupled plasma treatment using argon-containing gas (Ar-LAICP treatment). The Ar-LAICP treatment does not roughen the substrate film surface as much as the oxygen-LAICP treatment. In the antireflection film of Comparative Example 1, the ratio of the second interface length L2 to the first interface length L1 (L2 / L1) was significantly lower than 1.10. Therefore, the antireflection film of Comparative Example 1 failed to ensure adhesion of the antireflection layer.

[0141] In the antireflection film of Comparative Example 2, the HC layer of the substrate film does not contain particles, so the substrate film surface does not have irregularities caused by particles. In addition, the plasma treatment used in the manufacturing process of the antireflection film of Comparative Example 2 is, as described above, ion bombardment treatment (Ar-BB treatment) using capacitively coupled plasma with argon-containing gas. Compared to oxygen-LAICP treatment, Ar-BB treatment does not roughen the substrate film surface. In the antireflection film of Comparative Example 2, the ratio of the second interface length L2 to the first interface length L1 (L2 / L1) was significantly lower than 1.10. Therefore, the antireflection film of Comparative Example 2 failed to ensure adhesion of the antireflection layer.

[0142] In the antireflection film of Comparative Example 3, the HC layer of the substrate film contains 50% by mass of nanosilica particles. Therefore, as shown in FIG. 7, the surface of the substrate film 10 (the surface on the adhesive layer 21 side) has irregularities caused by the particles (not shown). In such an antireflection film of Comparative Example 3, the irregularities on the substrate film surface are reflected on the surface of the antireflection layer (the surface opposite the substrate film). Therefore, in the antireflection film of Comparative Example 3, the surface roughness Sa of the antireflection layer was large at 5.01 nm. Therefore, the total reflectance of the antireflection film of Comparative Example 3 was large at 0.46%.

[0143] In the antireflection film of Example 1, the HC layer of the substrate film does not contain particles. Therefore, as shown in FIG. 6, the surface of the substrate film 10 (the surface on the adhesive layer 21 side) does not have irregularities due to particles. Therefore, in the antireflection film of Example 1, the surface roughness Sa of the antireflection layer was small, at 1.53 nm. Therefore, the total reflectance of the antireflection film of Example 1 was 0.31%, which was smaller than the total reflectance (0.46%) of Comparative Example 3. Furthermore, as described above, the plasma treatment in the manufacturing process of the antireflection film of Example 1 was an inductively coupled plasma treatment using an oxygen-containing gas generated by applying high-frequency power to a low-inductance antenna (oxygen-LAICP treatment). Compared to Ar-LAICP treatment and Ar-BB treatment, oxygen-LAICP treatment can roughen the substrate film surface with fine irregularities on the nanometer order. As shown in FIG. 6, this is evident on the surface of the two layers, the adhesive layer 21 and the high refractive index layer 22a, formed on the substrate film 10, opposite the substrate film 10 (the interface between the high refractive index layer 22a and the low refractive index layer 22b). This surface has second micro-irregularities that originate from the micro-irregularities (first micro-irregularities) on the surface of the substrate film 10 and grow from the first micro-irregularities. Specifically, in the anti-reflection film of Example 1, the ratio (L2 / L1) of the second interface length L2 to the first interface length L1 was 1.10 or greater. Therefore, the anti-reflection film of Example 1 ensured adhesion of the anti-reflection layer. This is also true for Example 2.

[0144] [Table 1]

[0145] The above invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be interpreted as limiting. Modifications of the present invention that are obvious to those skilled in the art are intended to be included in the scope of the following claims. [Industrial Applicability]

[0146] The anti-reflection film of the present invention is suitably used in the manufacture of display devices such as liquid crystal displays and organic EL displays. [Explanation of symbols]

[0147] X Anti-Reflection Film H thickness direction D plane direction 10 Base film 10a 1st page 10b 2nd side 11 Resin film 12 Cured resin layer 21 Adhesion layer 22 Anti-reflection layer 22a, 22c High refractive index layer 22b, 22d Low refractive index layer 22e Antifouling surface

Claims

1. An antireflection film comprising a substrate film, an adhesive layer on the substrate film, and an antireflection layer on the adhesive layer, the antireflection layer includes a high refractive index layer in contact with the adhesive layer and a low refractive index layer on the high refractive index layer, in this order; the surface of the antireflection layer opposite to the substrate film has a surface roughness Sa of 4.5 nm or less; an antireflection film, wherein, in a cross-sectional view in a thickness direction of the antireflection film, a ratio of a second interface length at an interface between the high refractive index layer and the low refractive index layer to a first interface length at an interface between the base film and the adhesive layer is 1.10 or more.

2. 2. The anti-reflective film of claim 1, wherein the ratio is 2.00 or less.

3. 2. The antireflection film according to claim 1, wherein the total reflectance of light irradiated from a standard light source D65 at a wavelength of 380 nm to 780 nm on the antireflection layer side is 0.40% or less.

4. 100g / m ２ The anti-reflection film according to claim 1, having a moisture permeability of 24 hours or more.

5. The antireflection film according to claim 1 , wherein the peeling rate of the antireflection layer in the second test described below after the first test described below is less than 20%. First test: First, the substrate film side of the antireflection film is fixed to a glass plate, and then the antireflection layer of the antireflection film on the glass plate is irradiated with light at a temperature of 85°C, a relative humidity of 45%, and an irradiation intensity (integrated illuminance at 290 nm to 450 nm) of 150 mW / cm. ２ The mixture was exposed to light for 32.5 hours under the conditions of Second test: First, 11 parallel first incisions (2 mm apart) extending linearly in a first direction and 11 parallel second incisions (2 mm apart) extending linearly in a second direction perpendicular to the first direction are formed in the anti-reflection layer and the adhesive layer of the anti-reflection film on the glass plate using a cutter knife, and 100 grids are formed by the first and second incisions. Next, isopropyl alcohol is continuously dropped at 2 mL / min onto the 100 grid areas of the anti-reflection film, and a polyester wiper is slid over the area under the conditions of a wiper contact surface of 20 mm x 20 mm, a load of 1.5 kg / 20 mm, a sliding speed of 50 mm / sec, and 1000 reciprocations. Next, 1 mm of the 100 grids are removed. ２ The number of squares in which peeling of this magnitude or more has occurred is counted. Next, the count is divided by 100 to calculate the peeling rate (%).

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