Anti-reflective film

Abstract

An anti-reflection film X according to the present invention comprises: a base material film (10); an adhesion layer (21) on the base material film (10); and an anti-reflection layer (22) on the adhesion layer (21). The anti-reflection 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). The surface roughness Sa of the surface (22A) on the opposite side of the anti-reflection layer (22) to the base material film (10) is 4.5 nm or less. In a cross-sectional view of the anti-reflection film X in the thickness direction H, the ratio (L2 / L1) of a second interface length L2 at the interface between the high refractive index layer (22a) and the low refractive index layer (22b) to a first interface length L1 at the interface between the base material film (10) and the adhesion layer (21) is 1.10 or more.

Description

[Technical Field]

[0001] This invention relates to an anti-reflective film. [Background technology]

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

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-65437 [Overview of the project] [Problems that the invention aims to solve]

[0004] The anti-reflective film described in Patent Document 1 comprises a base film, an adhesion layer, and an anti-reflective layer in this order in the thickness direction. The base film has a hard coat (HC) layer on the side facing the adhesion layer. This HC layer contains silica particles. As a result, the HC layer has surface irregularities on the side facing the adhesion layer. The adhesion of the anti-reflective layer to the base film is enhanced by the anchoring effect of the surface irregularities of the HC layer and the physicochemical action of the adhesion layer. If the adhesion of the anti-reflective layer to the base film is insufficient, the anti-reflective layer will peel off from the base film.

[0005] However, in the antireflection film of Patent Document 1, the surface of the antireflection layer (the surface opposite to the base film) also has surface irregularities that follow the surface irregularities of the HC layer. The surface irregularities of the antireflection layer scatter part of the light incident on the antireflection film. The silica particles in the HC layer also scatter part of the light incident on the antireflection film. In the antireflection film, the more scattering of the incident light, the lower the antireflection property.

[0006] The present invention provides an antireflection film that can obtain a good reflection suppression effect while ensuring the adhesion of the antireflection layer to the base film.

Means for Solving the Problems

[0007] <000008...​​​​​​​​​​​​​​​​​​The present invention [5] includes the antireflection film according to any one of [1] to [4] above, 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, fix the side of the base film in the antireflection film to a glass plate. Next, irradiate light on the antireflection layer of the antireflection film on the glass plate under the conditions of a temperature of 85°C, a relative humidity of 45%, and an irradiation intensity (integrated illuminance of 290 nm to 450 nm) of 150 mW / cm 2 for 32.5 hours.

[0013] Second test: First, with respect to the antireflection layer and the adhesion layer in the antireflection film on the glass plate, use a cutter knife to form 11 parallel first cuts (at an interval of 2 mm) linearly extending in the first direction and 11 parallel second cuts (at an interval of 2 mm) linearly extending in the second direction orthogonal to the first direction, and form 100 meshes by the first and second cuts. Next, while continuously dropping isopropyl alcohol at 2 mL / min onto the area of the 100 meshes in the antireflection film, slide a polyester wiper under the conditions of a wiper contact surface of 20 mm × 20 mm, a load of 1.5 kg / 20 mm□, a sliding speed of 50 mm / second, and 100 reciprocations. Next, count the number of meshes in which peeling of 1 mm 2 or more has occurred among the 100 meshes. Next, divide the counted number by 100 to calculate the peeling rate (%).

Effect of the invention

[0014] In the anti-reflective film of the present invention, as described above, the surface roughness Sa of the surface of the anti-reflective layer 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 adhesion layer is 1.10 or more. In such an anti-reflective film, the scattering of light incident on the anti-reflective film at the surface of the anti-reflective layer can be suppressed by having the anti-reflective layer formed on the substrate film via an adhesion layer, and by having the above ratio of the first and second interface lengths be 1.10 or more. Therefore, the anti-reflective film of the present invention provides a good reflection suppression effect while ensuring adhesion of the anti-reflective layer to the substrate film. [Brief explanation of the drawing]

[0015] [Figure 1] This is a schematic cross-sectional view of one embodiment of the anti-reflective film of the present invention. [Figure 2] Figure 1 shows an example of a manufacturing method for the anti-reflective film. Figure 2A shows the cured resin layer formation process, Figure 2B shows the adhesion layer formation process, and Figure 2C shows the anti-reflective layer formation process. [Figure 3] Figure 1 is a schematic diagram of the apparatus used to carry out the plasma treatment process and the film formation process in an example of a method for manufacturing an anti-reflective film. [Figure 4] Figure 3 is a perspective view showing the positional relationship between the low-inductance antenna and the substrate film in the plasma processing chamber. [Figure 5] Figure 3 is a cross-sectional view showing the positional relationship between the low-inductance antenna and the substrate film in the plasma processing chamber. [Figure 6] This is a schematic diagram of the cross-sectional view image of the sample in Example 1. [Figure 7] This is a schematic diagram of the cross-sectional view image of the sample in Comparative Example 3. [Modes for carrying out the invention]

[0016] An anti-reflective film X according to one embodiment of the present invention comprises a base film 10, an adhesion layer 21, and an anti-reflective layer 22 in this order in the thickness direction H. The anti-reflective film X extends in a direction perpendicular to the thickness direction H (surface direction D). The anti-reflective film X is arranged, for example, on the outer surface of a display screen in a display device. Specifically, the base film 10 side of the anti-reflective 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 anti-reflective film X, the anti-reflective layer 22 has a surface 22A on the side opposite to the base film 10.

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

[0018] The resin film 11 is an element that ensures the strength of the anti-reflective 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 triacetylcellulose (TAC). These materials may be used individually or in combination of two or more. From the viewpoint of transparency and strength, the material of 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 also preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less. When the thickness of the resin film 11 is greater than or equal to the lower limit above, the strength of the anti-reflective film X can be ensured. When the thickness of the resin film 11 is less than or equal to the upper limit above, the handling of the base film 10 in the roll-to-roll process described later 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, even more preferably 95% or more, and also, for example, 100% or less. When the total light transmittance of the resin film 11 is equal to or greater than the above lower limit, good transparency can be ensured in the anti-reflective film X.

[0021] The cured resin layer 12 is a functional layer containing resin. Specifically, the cured resin layer 12 is a cured product of a curable resin composition containing a curable resin. An example of a 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 (top surface in Figure 1) of the anti-reflective layer 22.

[0022] Examples of curable resins 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 individually or in combination of two or more types. 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 curable resins include UV-curable resins and thermosetting resins. Preferably, the curable resin is a UV-curable resin. When the curable resin is a UV-curable resin, it can be cured without high-temperature heating, thus improving the manufacturing efficiency of the anti-reflective film X.

[0024] Furthermore, the curable resin may include, for example, a reactive diluent as described in Japanese Patent Publication No. 2008-88309. Specifically, the resin may include a polyfunctional (meth)acrylate.

[0025] When the base film 10 has a cured resin layer 12, it is preferable that the amount of inorganic oxide particles contained in the cured resin layer 12 be small. The fewer the inorganic oxide particles in the cured resin layer 12, the more effectively the scattering of light incident on the anti-reflective film X due to particles in the base film 10 can be suppressed, and the manufacturing cost of the anti-reflective film X can be reduced. Examples of materials for the inorganic oxide particles include silica, alumina, titania, zirconia, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. The inorganic oxide particle content of 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, even 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 also preferably 30 μm or less, more preferably 25 μm or less, and even more preferably 20 μm or less. When the thickness of the cured resin layer 12 is greater than or equal to the lower limit above, the function 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 anti-reflective layer 22 can be ensured. When the thickness of the cured resin layer 12 is less than or equal to the upper limit above, cracking of the cured resin layer 12 can be suppressed, and good transportability in the roll-to-roll process can be ensured.

[0027] The total light transmittance (JIS K 7375:2008) of the base film 10 is preferably 80% or more, more preferably 90% or more, even more preferably 95% or more, and also, for example, 100% or less. When the total light transmittance of the base film 10 is equal to or greater than the above lower limit, good transparency can be ensured in the anti-reflective film X.

[0028] The surface roughness Sa (arithmetic mean height based on ISO 25178-2:2012) of the first surface 10a of the base 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 also preferably 4.0 nm or less, more preferably 3.0 nm or less, and even more preferably 2.5 nm or less. When the surface roughness Sa of the first surface 10a is above the lower limit, the adhesion of the anti-reflective layer 22 to the base film 10 via the adhesion layer 21 is enhanced by the anchoring effect of the fine irregularities of the first surface 10a on the adhesion layer 21. When the surface roughness Sa of the first surface 10a is below the upper limit, it is suitable for suppressing a decrease in the scratch resistance of the surface 22A of the anti-reflective layer 22.

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

[0030] The adhesion layer 21 is located on one surface of the base film 10 in the thickness direction H. Specifically, the adhesion layer 21 is located 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 anti-reflective 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 anti-reflective layer 22 and transparency of the adhesion layer 21, indium tin composite oxide (ITO) or silicon oxide (SiOx) is preferred as the material for the adhesion layer 21. The silicon oxide used as the material for the adhesion layer 21 is preferably SiOx with a lower oxygen content than the stoichiometric composition, and more preferably SiOx with x of 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, even more preferably 3 nm or more, and also 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 greater than or equal to the lower limit above, adhesion between the base film 10 and the anti-reflective layer 22 can be ensured. When the thickness of the adhesion layer 21 is less than or equal to the upper limit above, the transparency of the adhesion layer 21 can be ensured.

[0032] The anti-reflective layer 22 is positioned on one surface of the adhesion layer 21 in the thickness direction H. The anti-reflective layer 22 is in contact with the adhesion layer 21. The anti-reflective layer 22 is a layer that suppresses the reflection intensity of ambient light (anti-reflective properties).

[0033] In this embodiment, the anti-reflective 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 anti-fouling surface layer 22e, in this order from the adhesion layer 21 side in the thickness direction H. The anti-reflective layer 22 of this embodiment is an anti-reflective layer with an anti-fouling surface layer. The high refractive index layer 22a is in contact with the adhesion layer 21. The high refractive index layer 22a and the low refractive index layer 22b are in contact. The low refractive index layer 22b and the high refractive index layer 22c are in contact. The high refractive index layer 22c and the low refractive index layer 22d are in contact. The high refractive index layers 22a and 22c are layers with relatively high refractive indices, and the low refractive index layers 22b and 22d are layers with relatively low refractive indices. In the anti-reflective layer 22, for example, the reflected light intensity 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 effects can be brought about by adjusting the optical film thickness (the product of the refractive index and thickness of the film) of each layer of the anti-reflective layer 22.

[0034] The high refractive index layer 22a (first high refractive index layer) is made of a high refractive index material with a refractive index of preferably 1.9 or higher at a wavelength of 550 nm. Examples of high refractive index materials include niobium oxide (Nb2O5), titanium oxide, zirconium oxide, indium tin composite oxide (ITO), and antimony tin composite oxide (ATO). From the viewpoint of achieving both a high refractive index and low absorption of visible light, niobium oxide (refractive index 2.33) is preferred as the high refractive index material. The optical film thickness of the high refractive index layer 22a is, for example, 20 nm or more, and also, 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 whose refractive index at a wavelength of 550 nm is preferably 1.6 or less. 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, silicon dioxide (refractive index 1.46) is preferred as the low refractive index material. The optical film thickness of the low refractive index layer 22b is, for example, 15 nm or more, and also, 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 whose refractive index at a wavelength of 550 nm is preferably 1.9 or higher. Examples of high refractive index materials include the materials described above for the high refractive index layer 22a, with niobium oxide being preferred. The optical film thickness of the high refractive index layer 22c is, for example, 60 nm or more, and also, 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 whose refractive index at a wavelength of 550 nm is preferably 1.6 or less. Examples of low refractive index materials include the materials described above for the low refractive index layer 22b, with silicon dioxide being preferred. The optical film thickness of the low refractive index layer 22d is, for example, 100 nm or more, and also, for example, 160 nm or less.

[0038] The total thickness from the high refractive index layer 22a to the low refractive index layer 22d in the antireflection layer 22 is preferably 180 nm or more, more preferably 200 nm or more, still more preferably 220 nm or more, and is preferably 320 nm or less, more preferably 280 nm or less, still 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 not less than the above lower limit value, the function of attenuating the reflected light intensity can be ensured in the antireflection layer 22. When the total thickness of the antireflection layer 22 is not more than the above upper limit value, cracking of the antireflection layer 22 can be suppressed.

[0039] The antifouling surface layer 22e is a layer having an antifouling function. The antifouling surface layer 22e is disposed on the low refractive index layer 22d. The antifouling function of the antifouling surface layer 22e includes a function of suppressing the adhesion of contaminants such as fingerprints to the film exposed surface when the antireflection film X is used, and a function of making it easier to remove the adhered contaminants.

[0040] Examples of the material of 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 the general formula (1), R 1 represents a linear or branched fluorinated alkyl group (carbon number is, for example, 1 or more and 20 or less) in which one or more hydrogen atoms in the alkyl group are substituted with fluorine atoms, and preferably represents a perfluoroalkyl group in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms.

[0043] R 2This represents a structure containing at least one repeating perfluoropolyether (PFPE) group, preferably a structure containing two repeating PFPE groups. Examples of repeating PFPE groups include repeating linear PFPE groups and repeating branched PFPE groups. Examples of repeating linear PFPE groups include -(OC n F 2n ) p Examples of structures represented by - (where n is an integer between 1 and 20, and p is an integer between 1 and 50; the same applies hereafter) include -(OC(CF3)2) p -A structure represented by -(OCF2CF(CF3)CF2) p Examples of structures represented by - include a repeating structure of a linear PFPE group, and more preferably a repeating structure of -(OCF2) p -and-(OC2F4) p - are listed.

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

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

[0046] m represents an integer greater than or equal to 1. Furthermore, m preferably represents an integer less than or equal to 20, more preferably less than or equal to 10, and even more preferably less than or equal to 5.

[0047] Among such alkoxysilane compounds having a perfluoropolyether group, the compound shown in the following general formula (2) is preferably used.

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

[0049] In general formula (2), q represents an integer between 1 and 50, and r represents an integer between 1 and 50.

[0050] Furthermore, the alkoxysilane compounds having a perfluoropolyether group may be used alone or in combination of two or more types.

[0051] In this embodiment, the antifouling surface layer 22e is a film formed by a dry coating method (dry coating film). Examples of 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 configuration in which the antifouling surface layer 22e is made of a material containing an alkoxysilane compound having a perfluoropolyether group, and the antifouling surface layer 22e is a dry coating film (preferably a vacuum-deposited film), is suitable for ensuring high adhesion of the antifouling surface layer 22e to the substrate, and therefore is suitable for ensuring the peel resistance of the antifouling surface layer 22e. High peel resistance of the antifouling surface layer 22e helps maintain the antifouling function of the antifouling surface layer 22e.

[0053] 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 also preferably 25 nm or less, more preferably 20 nm or less, and even more preferably 18 nm or less, from the viewpoint of ensuring the peel resistance of the antifouling surface layer 22e.

[0054] The anti-reflective layer 22 has a surface 22A (the surface of the anti-fouling surface layer 22e) on the side opposite to the base film 10. The surface roughness Sa (arithmetic mean height based on ISO 25178-2:2012) of 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, and even more preferably 1.8 nm or less. When the surface roughness Sa of surface 22A is below the above upper limit, light scattering on surface 22A can be suppressed. Furthermore, the surface roughness Sa of 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 greater than 1.5 nm, and even more preferably 1.6 nm or more. Having the surface roughness Sa of surface 22A above the above lower limit is suitable for reducing frictional force and ensuring good slipperiness on surface 22A. The method for measuring the surface roughness Sa is described later with respect to the examples.

[0055] In a cross-sectional view of the anti-reflective film X in the thickness direction H, the interface between the base film 10 and the adhesion layer 21 has fine irregularities (not shown). The interface between two adjacent layers within the anti-reflective layer 22 also has fine irregularities (not shown). Microscopic irregularities refer to irregularities on the order of nanometers, for example. In such a cross-sectional view of the anti-reflective film X 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 (second interface) to the first interface length L1 at the interface between the base film 10 and the adhesion layer 21 (first interface) 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 methods for measuring the first interface length L1 and the second interface length L2 are described later with respect to the examples. When the ratio (L2 / L1) is greater than or equal to the lower limit, the adhesion of the anti-reflective layer 22 to the anti-reflective film X can be improved by the anchoring effect. The ratio (L2 / L1) is preferably 2.00 or less, more preferably 1.50 or less, and more preferably 1.30 or less. When the ratio (L2 / L1) is less than or equal to the upper limit, the surface roughness Sa of the surface 22A of the anti-reflective layer 22 can be suppressed, thereby suppressing light scattering on the surface 22A. Methods for adjusting the ratio (L2 / L1) include, for example, adjusting the conditions for plasma treatment of the first surface 10a of the base film 10, and adding an appropriate amount of particles to the cured resin layer 12.

[0056] The total reflectance of the light irradiated from the standard light source D65 with wavelengths from 380 nm to 780 nm on the anti-reflective layer 22 side of the anti-reflective film X is preferably 0.40% or less, more preferably 0.36% or less, even more preferably 0.33% or less, and also, for example, 0.00% or more. When the total reflectance of the anti-reflective film X is below the above upper limit, the anti-reflective properties of the anti-reflective film X can be ensured. This makes it possible to suppress the reflection of ambient light and the reflection of images on the display screen on which the anti-reflective film X is placed in a display device. The method for measuring the total reflectance will be described later with respect to the examples.

[0057] The moisture permeability of the anti-reflective film X is preferably 100 g / m². 2 24 hours or more, more preferably 200 g / m² 2 24 hours or more, more preferably 300 g / m 2 24 hours or more, more preferably 330 g / m² 2 • It must be 24 hours or longer, and preferably 500 g / m² 2 • 24 hours or less, more preferably 400 g / m² 2 • 24 hours or less, more preferably 380 g / m² 2 • Less than 24 hours. The method for measuring moisture permeability is as described later with respect to the examples. If the moisture permeability of the anti-reflective film X is above the lower limit, moisture contained in the polarizers in the polarizer can be easily released to the outside through the anti-reflective film X in a heated environment after the anti-reflective film X is bonded to the polarizer, thus suppressing deterioration of the polarizers due to moisture. If the moisture permeability of the anti-reflective film X is below the upper limit, deterioration of the polarizer can be suppressed in a humidified environment after the anti-reflective film X is bonded to the polarizer. As a method for adjusting moisture permeability, for example, adjustment of the pressure (atmospheric pressure) inside the deposition chamber during sputter deposition, as described later, can be mentioned.

[0058] The peeling rate of the anti-reflective layer 22 of the anti-reflective film X in the second test following the first test (accelerated weathering test) is preferably less than 20%, more preferably 15% or less, even more preferably 10% or less, and most preferably less than 10%, from the viewpoint of ensuring the adhesion of the anti-reflective layer 22. The methods of the first and second tests are described more specifically in the examples below. When the peeling rate of the anti-reflective layer 22 is below the above upper limit, the deterioration of the anti-reflective properties of the anti-reflective film X due to peeling of the anti-reflective layer 22 can be suppressed in practical use.

[0059] Exam 1: First, the base film 10 side of the anti-reflective film X is fixed to the glass plate. Next, the anti-reflective layer 22 of the anti-reflective film X on the glass plate is subjected to an irradiation intensity (integrated illuminance from 290nm to 450nm) of 150mW / cm² at a temperature of 85°C, relative humidity of 45%, and an irradiation intensity of 150mW / cm². 2 Under these conditions, light is shone for 32.5 hours.

[0060] Second Exam: First, using a utility knife, 11 parallel first cuts (2 mm apart) extending linearly in a first direction and 11 parallel second cuts (2 mm apart) extending linearly in a second direction perpendicular to the first direction are made in the anti-reflective layer 22 and adhesion layer 21 of the anti-reflective film X on the glass plate after the first test, forming 100 grids with the first and second cuts. Next, isopropyl alcohol is continuously dropped at a rate of 2 mL / min onto the area of ​​the 100 grids in the anti-reflective film X while sliding a polyester wiper under the conditions of a wiper contact surface of 20 mm × 20 mm, a load of 1.5 kg / 20 mm square, a sliding speed of 50 mm / second, and 1000 reciprocations. Next, of the 100 grids, 1 mm 2 Count the number of squares where peeling occurred. Next, divide the count by 100 to calculate the peeling rate (%).

[0061] In the anti-reflective film X, as described above, the surface roughness Sa of the surface 22A of the anti-reflective 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 adhesion layer 21 is 1.10 or more. In such an anti-reflective film X, the scattering of light incident on the anti-reflective film X at the surface 22A can be suppressed by having a surface roughening of the surface 22A of the surface 22A. The above ratio (L2 / L1) of the first interface length L1 and the second interface length L2 being 1.10 or more can be achieved, for example, by roughening the surface of a base film (base film 10 in this embodiment) that substantially does not contain particles on its surface, and then forming an anti-reflective layer on that surface via a predetermined adhesion layer. The anti-reflective layer 22 is formed on the base film 10 via an adhesion layer 21, and the ratio of the lengths of the first and second interfaces is 1.10 or greater, thereby ensuring good adhesion of the anti-reflective layer 22 to the base film 10. Furthermore, because the base film 10 does not contain particles, scattering of light incident on the anti-reflective film X due to particles within the base film 10 can be suppressed.

[0062] With such an anti-reflective film X, a good reflection suppression effect can be obtained while ensuring good adhesion of the anti-reflective layer 22 to the base film 10.

[0063] Figures 2A to 2C illustrate an example of a manufacturing method for the anti-reflective film X. This manufacturing method includes a cured resin layer formation step (Figure 2A), a plasma treatment step, and a film formation step (Figures 2B and 2C).

[0064] In the cured resin layer formation process, as shown in Figure 2A, a cured resin layer 12 is formed on a long resin film 11. This yields a base film 10. The cured resin layer 12 can be formed by applying the above-mentioned curable resin composition to the resin film 11 to form a coating film, and then curing this coating film. The curable resin composition may optionally contain other components besides the above-mentioned curable resin. Other components include, for example, solvents and leveling agents. Examples of solvents include butyl acetate, ethyl acetate, toluene, and cyclopentanone. If the curable resin composition contains an ultraviolet-curable resin as the curable resin, the curable resin composition preferably contains a photopolymerization initiator. If the curable resin composition contains a thermosetting resin as the curable resin, the curable resin composition preferably contains a thermal polymerization initiator.

[0065] If the curable resin composition contains a solvent, the coating on the resin film 11 is dried after application of the curable resin composition. 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 more, and for example, 10 minutes or less.

[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 ultraviolet irradiation light sources include high-pressure mercury lamps and LED lights. The cumulative amount of ultraviolet irradiation is, for example, 100 mJ / cm². 2 That's all, and also, for example, 500 mJ / cm 2 The following applies:

[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 more, and for example, 10 minutes or less.

[0068] As described above, a long base film 10 can be manufactured. In this embodiment, a roll of the long base film 10 is prepared. Specifically, the base film 10 is wound so that the first surface 10a of the base film 10 faces inward in the radial direction of the roll.

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

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

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

[0072] The connection chamber C1 is located after the feed chamber R1 and before the plasma processing chamber C2 in the direction of travel of the work film W. A predetermined number of guide rollers G for guiding the work film W are provided inside the connection chamber C1. The connection chamber C1 is connected to a vacuum pump (not shown) and is configured to allow adjustment of the chamber pressure. When the apparatus Y is in operation, the pressure inside the connection chamber C1 is maintained at a predetermined pressure between the pressure inside the feed chamber R1 and the pressure inside the plasma processing chamber C2. This ensures a differential pressure between the feed chamber R1 and the plasma processing chamber C2.

[0073] Plasma processing chamber C2 is located between connection chamber C1 and connection chamber C3 in the direction of travel of the work film W. Plasma processing is carried out in plasma processing chamber C2 as described later. A first line L1 with a flow control valve for introducing gas into the chamber is also connected to plasma processing chamber C2.

[0074] In this embodiment, the plasma processing chamber C2 is equipped with a plurality of low-inductance antennas (LAs) 71. A low-inductance antenna is defined as an antenna having a low inductance of 7.5 μH or less and capable of generating inductively coupled plasma by applying high-frequency power. In this embodiment, LA71 is located inside the plasma processing chamber C2, supported by a mounting bracket 72 and covered by a cover block 73 (not shown in Figure 4), as shown in Figures 4 and 5 (the case where there are 4 LA71s is illustrated as an example).

[0075] Multiple LA71s are arranged in alignment so as to be aligned in the direction of travel of the base film 10 and in a direction perpendicular to the direction of travel (the width direction of the base film 10). The mounting fixture 72 is a vacuum flange. As shown in Figure 5, the LA71s are fixed to the mounting fixture 72 via a field-through 74. As shown in Figure 4, the mounting fixture 72 is assembled into an opening 75 provided in the wall of the plasma processing chamber C2. Specifically, the mounting fixture 72 is assembled to the opening 75 with a sealing member (not shown) sandwiched between the wall of the plasma processing chamber C2 and the mounting fixture 72. Outside the plasma processing chamber C2, the LA71s are electrically connected to a high-frequency power supply (RF power supply) via an impedance matching device. Such LA71s are formed of a conductor. Examples of conductors include copper and silver, with copper being preferred. The LA71s may be covered with an insulator. Examples of insulators include glass and quartz.

[0076] The cover block 73 comprises a block body 73A and a plurality of partition plates 73B. The block body 73A has a plurality of storage spaces 73a. One LA 71 is housed in each storage space 73a. The partition plates 73B are arranged to close the storage spaces 73a. The inside of the storage spaces 73a is a sealed space. In the cover block 73, the block body 73A is made of aluminum, for example. 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 Figure 5) between the base film 10 running inside 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 LA71 due to plasma treatment without excessively reducing the plasma conversion efficiency due to the power applied to LA71, and also helps to suppress damage to the substrate film 10 being plasma treated.

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

[0078] LA71 extends from the mounting fixture 72 toward the base film 10. Preferably, LA71 extends perpendicular to the mounting fixture 72. The extension length d1 of LA71 from the mounting fixture 72 is, for example, 30 to 150 mm. The maximum length d2 of LA71 in the planar direction of the base film 10 is, for example, 50 to 150 mm. The separation distance d3 (shown in Figure 5) between LA71 and the base film 10 is, for example, 50 to 200 mm. Preferably, the extension length d1 and the separation distance d3 are the same. The ratio of the separation distance d3 to the extension length d1 (d3 / d1) is, for example, 0.5 to 3.5. The number of LA71 (number of rows) arranged spaced apart in the running direction of the base film 10 may be 1, 2 or 3, or 4 or more if necessary, depending on the running speed of the base film 10 (i.e., plasma processing time). In the running direction of the base film 10, the distance d4 between the centers of adjacent LA71 is, for example, 100 to 500 mm. In the width direction of the base film 10, the distance d5 between the centers of adjacent LA71 is, for example, 200 to 500 mm. By adjusting the distance d5 between centers, the uniformity of the plasma density in the width direction of the base film 10 can be controlled. It is preferable that the distances d4 and d5 between centers are the same. The ratio of the distance d5 to the distance d4 (d5 / d4) is, for example, 0.5 to 2.0. The center points of the extensions 71a of the four LA71 preferably form a square with vertices. With such a set of LA71, a high-density plasma can be generated. As the LA71, for example, a high-frequency antenna for plasma generation described in Japanese Patent Application Publication No. 2013-258153 may be used.

[0079] In this embodiment, the plasma processing chamber C2 further includes a transport roller 53. The transport roller 53 is the main guide roller for transporting the work film W within the plasma processing chamber C2. The transport roller 53 has a temperature control function that allows for heating or cooling of the work film W. In other words, the transport roller 53 is a transport roller with a temperature control function. When the apparatus Y is in operation, the transport roller 53 transports the base film 10 while in contact with the second surface 10b of the base film 10. The LA71 is positioned opposite the transport roller 53. With the apparatus Y equipped with such a plasma processing chamber C2, in the plasma processing step S2, the base film 10 can be cooled or heated by the temperature-controlled transport roller 53 that contacts the base film 10, while plasma processing is performed on the base film 10. Temperature control of the base film 10 can suppress thermal deformation of the base film 10, and the influence of such thermal deformation on the transport of the base film 10 can also be suppressed.

[0080] The connection chamber C3 is positioned after the plasma processing chamber C2 and before the film deposition chamber C4 in the direction of travel of the work film W. A predetermined number of guide rollers G for guiding the work film W are provided inside the connection chamber C3. The connection chamber C3 is connected to a vacuum pump (not shown) and is configured to allow adjustment of the chamber pressure. When the apparatus Y is in operation, the pressure inside the connection chamber C3 is maintained at a predetermined pressure between the pressure inside the plasma processing chamber C2 and the pressure inside the film deposition chamber C4. This ensures a differential pressure between the plasma processing chamber C2 and the film deposition chamber C4.

[0081] The deposition chamber C4 is located next to the connection chamber C3 in the direction of travel of the work film W. The deposition chamber C4 is also connected to a vacuum pump (not shown) and is configured to allow adjustment of the vacuum level inside the chamber. In the deposition chamber C4, the deposition process from the high refractive index layer 22a to the low refractive index layer 22d is carried out, as described later.

[0082] In this embodiment, the deposition chamber C4 is a sputter deposition chamber. The deposition chamber C4 comprises a deposition roller 54 and a plurality of sputter chambers 60 (sputter chambers 60a to 60e) (the case where there are 5 sputter chambers 60 is illustrated as an example). The deposition roller 54 is the main guide roller for transporting the work film W within the deposition chamber C4. The deposition roller 54 has a temperature control function that allows heating or cooling of the work film W. The sputter chambers 60 are partitioned spaces within the deposition chamber C4. The plurality of sputter chambers 60 are arranged along the circumferential direction of the deposition roller 54. Each sputter chamber 60 opens toward the deposition roller 54. A cathode 61 is provided inside the sputter chamber 60. A target (not shown) as a deposition material supply is placed on the cathode 61. The target is placed on the target so as to face the deposition roller 54. Each sputtering chamber 60 is equipped with a power supply (not shown) for applying 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. An MF-AC power supply refers to an AC power supply with a frequency band of several kHz to several MHz. Each sputtering chamber 60 is connected to a necessary number of second lines (not shown) with flow control valves for introducing gas into the chamber. In addition, a predetermined number of guide rollers G for guiding the work film W are provided inside the film deposition chamber C4.

[0083] The connection chamber C5 is located between the connection chamber C4 and the film deposition chamber C6 in the direction of travel of the work film W. A predetermined number of guide rollers G for guiding the work film W are provided inside the connection chamber C5.

[0084] The deposition chamber C6 is located between the connection chamber C5 and the winding chamber R2 in the direction of travel of the work film W. In this embodiment, the deposition chamber C6 is a vacuum deposition chamber. The deposition chamber C6 includes a material holding section 62 and a deposition amount adjustment valve (not shown) whose opening degree can be controlled. The deposition chamber C6 is connected to a vacuum pump (not shown) and is configured to allow adjustment of the chamber pressure. A predetermined number of guide rollers G are provided inside the deposition chamber C6 to guide the work film W. In this deposition chamber C6, the process of depositing the antifouling surface layer 22e is carried out.

[0085] A film deposition material supply (not shown) is positioned in the material holding section 62 so as to face the work film W being transported within the film deposition chamber C6. The material holding section 62 may have 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 deposition material supply.

[0086] The apparatus Y described above is used to sequentially perform the plasma treatment process and the film deposition process. Specifically, it is as follows:

[0087] The work film W is unfurled from the unfurling chamber R1. After being unfurled from the unfurling chamber R1, the work film W sequentially passes through the connection chamber C1, the plasma processing chamber C2, the connection chamber C3, the film deposition chamber C4, the connection chamber C5, and the film deposition chamber C6, and is wound up in the winding chamber R2. The travel speed of the work 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 unfurling chamber R1 to the winding chamber R2 is not opened to the atmosphere along the way, and the process is carried out in a reduced-pressure atmosphere in this line. The reduced-pressure atmosphere is preferably a vacuum. A vacuum preferably means a reduced-pressure atmosphere of 7 Pa or less.

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

[0089] During plasma processing, oxygen is supplied to the plasma processing chamber C2 via the first line L1. In addition to oxygen, an inert gas may be supplied to the plasma processing chamber C2. Examples of inert gases include argon, krypton, and xenon. The gas in the plasma processing chamber C2 may also contain other gases besides 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 processing 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 above the above lower limit, a high-density oxygen plasma can be generated. This is useful for creating nanometer-order fine irregularities on the first surface 10a of the substrate film 10, and for high activation by cleaning the first surface 10a.

[0090] The pressure inside the plasma treatment chamber C2 during plasma treatment (first pressure) is preferably 0.1 Pa or higher, more preferably 0.2 Pa or higher, even more preferably 0.3 Pa or higher, and also preferably 7 Pa or lower, more preferably 5 Pa or lower, and even more preferably 3 Pa or lower. When the first pressure is above the lower limit, a plasma environment with sufficient density for surface modification treatment of the first surface 10a of the substrate film 10 can be formed inside the plasma treatment chamber C2 during plasma treatment. When the first pressure is below the upper limit, thermal damage to the first surface 10a caused by excessively high-density plasma can be suppressed during plasma treatment, and excessive roughening of the first surface 10a can also be suppressed. Suppression of excessive roughening helps to suppress 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 treatment chamber C2.

[0091] The frequency of the high-frequency power applied to LA71 during plasma processing is preferably 1 MHz or higher, more preferably 5 MHz or higher, even more preferably 10 MHz or higher, and also preferably 100 MHz or lower, more preferably 80 MHz or lower, and even more preferably 60 MHz or lower. When the frequency is above the lower limit, the plasma discharge can be stabilized while increasing the plasma current density during plasma processing. When the frequency is below the upper limit, the antenna potential can be suppressed, and therefore damage to the substrate film 10 by the plasma can be suppressed. 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 also 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 above the lower limit, a high-density plasma environment can be formed in the plasma processing chamber C2 during plasma processing by inductively coupled plasma. When the high-frequency power is below the upper limit, excessive damage to the substrate by the plasma can be suppressed.

[0092] In the plasma treatment process, the plasma current density at the intermediate position between LA71 and the substrate film 10 is preferably 1.0 mA / cm². 3 More preferably, 2.0 mA / cm² 3 More preferably, 3.0 mA / cm² 3 In addition, preferably 10 mA / cm² 3 More preferably, 8 mA / cm 3 More preferably, 4 mA / cm 3 The following is true: Inductively coupled plasma processing using a low-inductance antenna can achieve a higher plasma current density than the capacitively coupled plasma processing described above (for example, it can achieve a plasma density approximately 100 times higher). When the plasma current density is above the lower limit, sufficient plasma-induced oxygen particles can be secured in the plasma treatment chamber C2 during plasma treatment, and the first surface 10a of the substrate film 10 can be appropriately surface-modified. When the plasma current density is below the upper limit, damage to the first surface 10a due to excessively high density of plasma-induced oxygen particles can be suppressed during plasma treatment. Methods for adjusting the plasma current density include, for example, adjusting the amount of oxygen gas introduced into the plasma processing chamber C2, adjusting the frequency of the high-frequency power supply, and adjusting the magnitude of the applied power.

[0093] In the film formation process, first, in the film formation chamber C4, following the plasma treatment process, an adhesion layer 21 and an inorganic layer 22 are sequentially formed on the first surface 10a of the substrate film 10 by sputtering under 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 the target (film deposition material) placed on the cathode 61 within the sputtering chamber 60. This generates a glow discharge, ionizing the gas atoms, which then collide with the target surface at high speed, ejecting the target material from the target surface and depositing it onto the work film W. Examples of sputtering gases include argon, krypton, and xenon.

[0095] When the film deposition material is a metal oxide, the sputtering method may be a reactive sputtering method. In a 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 via another second line. In a reactive sputtering method, the target is, for example, the metal in the metal oxide that forms each layer.

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

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

[0098] Next, a high refractive index layer 22a is formed on the adhesion layer 21 by sputtering in the sputtering chamber 60b. When forming an Nb2O5 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 an Nb2O5 layer as the high refractive index layer 22c, an 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 deposition process, an antifouling surface layer 22e is further formed in the deposition chamber C6. In this step, the antifouling surface layer 22e is formed on the low refractive index layer 22d of the work film W by vacuum deposition as a dry coating method in the deposition chamber C6. Specifically, with the deposition chamber C6 reduced to a vacuum by operating a vacuum pump, the deposition material supply material (not shown) placed in the material holding section 62 is heated to a predetermined temperature, and the vacuum deposition method is carried out.

[0103] In apparatus Y, after the plasma treatment process and the film deposition process, the anti-reflective film X, which is the work film W, enters the winding chamber R2 and is wound up by the winding roller 52.

[0104] In this manner, a long-length anti-reflective film X can be manufactured.

[0105] The anti-reflective layer 22 of the anti-reflective film X does not necessarily have the anti-fouling surface layer 22e described above. In that case, the surface of the low refractive index layer 22d opposite to the base film 10 becomes the surface 22A of the anti-reflective layer 22. An anti-reflective film X without the anti-fouling surface layer 22e can be manufactured by omitting the step in the film deposition chamber C6 in the above-described manufacturing process for the anti-reflective film X. [Examples]

[0106] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples. Furthermore, the specific numerical values ​​such as the amounts (contents), physical properties, and parameters described below can be substituted with the upper limits (numerical values ​​defined as "less than or equal to" or "less than") or lower limits (numerical values ​​defined as "greater than or equal to" or "greater than") of the corresponding amounts (contents), physical properties, and parameters described in the "Modes for Carrying Out the Invention" above.

[0107] [Example 1] The anti-reflective film of Example 1 was produced by sequentially carrying out the following steps.

[0108] First, a base film was prepared by forming a hard coat layer on one side of a triacetylcellulose (TAC) film as a resin film (preparation step). Specifically, 100 parts by mass (solid content equivalent) of a butyl acetate solution of UV-curable acrylic urethane resin (product name "Luxidia 17-806", solid content concentration 80% by mass, manufactured by DIC Corporation), 5 parts by mass of a photopolymerization initiator (product name "IRGACURE 906", manufactured by BASF Corporation), and 0.01 parts by mass of a leveling agent (product name "GRANDIC PC4100", manufactured by DIC Corporation) were mixed to obtain a mixture. Next, the solid content concentration of the mixture was adjusted to 36% by mass by adding a mixed solvent of cyclopentanone (CPN) and propylene glycol monomethyl ether (PGM) (the mass ratio of CPN to PGM is 45:55). This prepared the first resin composition. Meanwhile, a long piece of TAC film (product name "KC4UY", thickness 40 μm, manufactured by Konica Minolta Advanced Layers) was prepared. Next, the first resin composition was applied to one side of the TAC film to form a coating. Then, this coating was dried by heating and cured by ultraviolet irradiation. This formed a 7 μm thick hard coat (HC) layer on the TAC film. The heating temperature was set to 90°C, and the heating time was set to 1 minute. For ultraviolet irradiation, a high-pressure mercury lamp was used as the light source, and ultraviolet light with a wavelength of 365 nm was irradiated onto the coating film, with an integrated irradiation dose of 300 mJ / cm². 2 Thus, a TAC film with an HC layer was prepared as a base film.

[0109] Next, under vacuum, the substrate film was transported using a roll-to-roll method while a plasma treatment process and a subsequent film deposition process were carried out on the substrate film (roll-to-roll process). For the plasma treatment process and the film deposition process, an apparatus (first apparatus) capable of performing a roll-to-roll process on a work film was used. The first apparatus comprises a feeding chamber, a plasma treatment chamber (first plasma treatment), a first film deposition chamber, a second film deposition chamber, and a winding chamber. The feeding chamber, plasma treatment chamber, first film deposition chamber, second film deposition chamber, and winding chamber are arranged in this order and are in communication with each other. The feeding chamber is equipped with a feeding roller. A roll of the substrate film described above was set on the feeding roller as the work film. The plasma treatment chamber is equipped with a transport roller with a temperature control function (transport roller 53 in Figure 3) and four low-inductance antennas (LA71 in Figures 4 and 5) covered with a cover block (cover block 73 in Figure 5), as shown in Figures 4 and 5. Each low-inductance antenna has an extension (extension 71a in Figure 4) parallel to the substrate film. For the four low-inductance antennas, the extension length d1 is 88 mm, the maximum length d2 (length of the extension) is 100 mm, the separation distance d3 is 112 mm, the center-to-center distance d4 is 290 mm, and the center-to-center distance d5 is 280 mm (Figures 4 and 5). Each low-inductance antenna is electrically connected to a high-frequency power supply (RF power supply, frequency 13.56 MHz) via an impedance matching device outside the plasma processing chamber. The separation distance d' between the substrate film and the cover block running inside the plasma processing chamber is 100 mm. The first deposition chamber is a sputter deposition chamber and comprises a deposition roller (deposition roller 54 in Figure 3) and the first to fifth sputter chambers (sputter chambers 60a to 60e in Figure 3). Each sputter chamber is a partitioned space within the first deposition chamber. The first to fifth sputtering chambers are arranged in this order along the circumferential direction of the deposition roller and in the direction of travel of the substrate film. Each sputtering chamber is equipped with a cathode positioned opposite the deposition roller. Each sputtering chamber is connected to a second line (not shown) with the necessary number of flow control valves for introducing gas into the chamber. The second deposition chamber is a vacuum deposition chamber and is equipped with a material holding section (material holding section 62 in Figure 3).The winding chamber is equipped with winding rollers.

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

[0111] The ultimate vacuum level of the plasma processing chamber is 1.0 × 10⁻⁶ -4 After evacuating the inside of the apparatus to a vacuum of Pa, oxygen was introduced into the plasma processing chamber to set the pressure inside the plasma processing chamber to 1.5 Pa. By applying a high-frequency power of 2 kW to four low-inductance antennas using a high-frequency power supply, an inductively coupled plasma of oxygen-containing gas was formed around the antennas (this plasma treated the surface of the HC layer of the substrate film). The plasma current density at the intermediate position between the low-inductance antennas and the substrate film was 1.3 mA / cm². 3 That was the case. The plasma current density was measured using a Langmuir probe for plasma measurement.

[0112] In the first deposition chamber, an adhesion 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 substrate film after plasma treatment. Specifically, while the substrate film was being transported and cooled by the deposition roll in the first deposition chamber, an adhesion 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 adhesion 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 deposition temperature (temperature of the deposition roll) was -8°C. More specifically, it is as follows.

[0113] In the first sputtering chamber, a 4 nm thick ITO layer was formed as an adhesion layer using reactive sputtering (adhesion layer formation process). In this process, the vacuum level achieved in the first deposition chamber was 1.0 × 10⁻⁶. -4 After evacuating to a vacuum of 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 per 100 volumes of argon into the first sputtering chamber was 10 volumes. 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 to apply voltage to the target (the same was used in the second to fifth sputtering chambers described later). The discharge power was set to 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 using reactive sputtering. In this process, after the first deposition 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 per 100 volumes of argon into the second sputtering chamber was 5 volumes. An Nb target was used as the target. 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 using reactive sputtering. In this process, after the first deposition 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 volumes of argon into the third sputtering chamber was 30 volumes. A Si target was used as the target. The discharge power was set to 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 using reactive sputtering. In this process, after the first deposition 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 inside the fourth sputtering chamber was set to 0.5 Pa. The amount of oxygen introduced into the fourth sputtering chamber for every 100 volumes of argon was 13 volumes. An Nb target was used as the target. The discharge power was set to 27.5 kW.

[0117] In the fifth sputtering chamber, an 84 nm thick SiO2 layer (refractive index 1.46) was formed as the second low refractive index layer using reactive sputtering. In this process, after the first deposition 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 inside the fifth sputtering chamber was set to 0.2 Pa. The amount of oxygen introduced per 100 volumes of argon into the fifth sputtering chamber was 30 volumes. A Si target was used as the target. The discharge power was 20.5 kW.

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

[0119] As described above, the anti-reflective film of Example 1 was fabricated. The anti-reflective film of Example 1 comprises a base film with an HC layer, an adhesion layer on the HC layer, and an anti-reflective layer (first high refractive index layer / first low refractive index layer / second high refractive index layer / second low refractive index layer / anti-fouling surface layer) on the adhesion layer. The surface of the HC layer of the base film of the anti-reflective film of Example 1 is plasma treated. 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 anti-reflective film of Example 2 was prepared in the same manner as the anti-reflective 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, it was as follows.

[0121] In the preparation process, first, 80 parts by mass (solid content equivalent) of UV-curable acrylic urethane resin (product name "UT-7314", manufactured by Mitsubishi Chemical Corporation), 20 parts by mass (solid content equivalent) of polyfunctional acrylate mainly composed of pentaerythritol triacrylate (product name "Viscote #300", manufactured by Osaka Organic Chemical Industry Co., Ltd.), 1.5 parts by mass of photopolymerization initiator (product name "Omnirad127D", manufactured by BASF), and 0.06 parts by mass of leveling agent (product name "Polyflow LE-303", leveling agent containing a silicone compound, manufactured by Kyoeisha Chemical Co., Ltd.) were mixed to obtain a mixture. Next, a mixed solvent of butyl acetate and cyclopentanone (CPN) (mass ratio of butyl acetate to CPN is 70:30) was added to the mixture as a solvent to prepare a resin composition with a solid content concentration of 40% by mass.

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

[0123] [Comparative Example 2] First, a base film (TCA film / HC layer) was prepared by forming an HC layer on one side of a TAC film, similar to the preparation process in Example 1.

[0124] Next, a plasma treatment process and a subsequent film deposition process were carried out on the substrate film while it was being transported in a roll-to-roll manner under vacuum (roll-to-roll process). A second apparatus capable of performing a roll-to-roll process on the work film was used for the plasma treatment and film deposition processes. The second apparatus has the same configuration as the first apparatus, except that it is equipped with a second plasma treatment chamber instead of the first plasma treatment chamber. The second plasma treatment chamber is equipped with a pair of planar electrodes for plasma generation, namely a cathode electrode and an anode electrode (both rectangular electrodes made of SUS304). The pair of planar electrodes are spaced 50 mm apart and are arranged parallel to the substrate film passing through the second plasma treatment chamber. The anode electrode is positioned 35 mm away from the substrate film passing through the plasma treatment chamber and is grounded outside the plasma treatment chamber. The cathode electrode is positioned facing the HC layer surface of the substrate film and is electrically connected to a high-frequency power supply (RF power supply, 13.56 MHz) via an impedance matching device. Each electrode facing the base film has a length of 110 mm in the film travel direction and a length of 430 mm in the width direction.

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

[0126] The ultimate vacuum level in the second plasma processing chamber is 1.0 × 10⁻⁶ -4 After evacuating the apparatus to a vacuum of Pa, argon was introduced into the second plasma processing chamber, and the pressure inside the plasma processing chamber was set to 0.5 Pa. By applying 500 W of power from a high-frequency power supply between the planar electrodes, a capacitively coupled plasma (CCP) was generated. Under this plasma environment, bombardment treatment with argon ions (Ar-BB treatment) was performed on the surface of the HC layer of the substrate film.

[0127] In the first deposition chamber, layers from the adhesion layer to the second low refractive index layer were sequentially formed on the substrate film after plasma treatment, similar to the method described above for Example 1. In the second deposition chamber, an antifouling surface layer was formed on the second low refractive index layer, similar to the method described above for Example 1.

[0128] [Comparative Example 3] The anti-reflective film of Comparative Example 3 was prepared in the same manner as the anti-reflective 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 was as follows.

[0129] In the preparation process, first, 83 parts by mass (solid content equivalent) of an acrylic monomer composition containing nanosilica particles (product name "NC035HS", nanosilica concentration 60% by mass, manufactured by Arakawa Chemical Industries, Ltd.), 17 parts by mass (solid content equivalent) of a UV-curable polyfunctional urethane acrylate (product name "Beamset 580", solid content concentration 70% by mass, manufactured by Arakawa Chemical Industries, Ltd.), 1.5 parts by mass of a photopolymerization initiator (product name "OMNIRAD127D", manufactured by IGM Resins), 0.15 parts by mass (solid content equivalent) of a leveling agent (product name "LE303", solid content concentration 40% by mass, manufactured by Kyoeisha Chemical Co., Ltd.), and butyl acetate were mixed to prepare a second resin composition with a solid content concentration of 42% by mass. Meanwhile, a long TAC film (product name "KC4UY", thickness 40 μm, manufactured by Konica Minolta Advanced Layers) was prepared. Next, the second resin composition was applied to one side of the TAC film to form a coating. This coating was then dried by heating and cured by ultraviolet irradiation. This formed a 7 μm thick HC layer on the TAC film. The heating temperature was 90°C for 1 minute. For ultraviolet irradiation, a high-pressure mercury lamp was used as the light source, and ultraviolet light with a wavelength of 365 nm was irradiated onto the coating, with an integrated irradiation dose of 300 mJ / cm². 2 Thus, a TAC film with an HC layer was prepared as a base film. The HC layer of the base film in Comparative Example 3 contains 50% by mass of nanosilica particles.

[0130] <Surface roughness> The surface roughness of the anti-reflective layer surface was investigated for each of the anti-reflective films in Example 1, Example 2, and Comparative Examples 1-3. Specifically, the surface roughness Sa (arithmetic mean height based on ISO 25178-2:2012) of the exposed surface of the anti-reflective layer in the anti-reflective films was measured in a 1 μm square observation image using an atomic force microscope (product name "Dimension Edge SPC-160113-01", manufactured by Bruker). In this measurement, the measurement mode was set to tapping mode, and an antimond-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 anti-reflective film in Example 1, Example 2, and Comparative Examples 1-3 was measured as follows.

[0132] First, the side of the anti-reflective film opposite the anti-reflective layer was bonded to a black acrylic plate (2 mm thick) using a predetermined transparent acrylic adhesive. This resulted in a laminated film. Next, a piece of film for measurement was cut from the laminated film. Then, the spectrum of total reflected light (including specular reflected light) was measured for the film piece using a spectrophotometer (product name "UH4150", manufactured by Hitachi High-Tech Science Co., Ltd.). For the measurement, a standard light source D65 was used as the light source, and the film piece was placed inside the spectrophotometer so that light shone on the film piece from the anti-reflective layer side. The measurement was performed using the integrating sphere measurement mode of the spectrophotometer. The reflectance measured is the total reflectance (visible reflectance) of the light irradiated from the standard light source D65 with wavelengths of 380 nm to 780 nm on the anti-reflective layer side of the film piece (anti-reflective film). The measurement results are shown in Table 1.

[0133] <Moisture permeability> The moisture permeability in the thickness direction of each anti-reflective film for Example 1, Example 2, and Comparative Examples 1-3 was measured in accordance with JIS K7129:2008 Annex B (Infrared Sensor Method). The measurements were performed 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> For each of the anti-reflective films in Example 1, Example 2, and Comparative Examples 1-3, the ratio of the second interface length L2 (the interface between the high-refractive-index layer and the low-refractive-index layer) to the first interface length L1 (the interface between the substrate film and the adhesion layer) in a cross-sectional view was investigated. Specifically, the results are as follows.

[0135] First, a sample for cross-sectional observation of the anti-reflective film was prepared using the FIB microsampling method. For the FIB microsampling method, a FIB device (product name "FB2200", manufactured by Hitachi) was used, and the acceleration voltage was set to 10kV. Next, the cross-section of the sample was observed using FE-TEM. For this observation, a FE-TEM device (product name "JEM-2800", manufactured by JEOL) was used, and the acceleration voltage was set to 200kV. Figure 6 schematically shows the observed image of the cross-section of the sample from Example 1. In the observed image from Example 1, the HC layer 12 of the base film 10, the adhesion 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. Figure 7 schematically shows the observed image of the cross-section of the sample from Comparative Example 3. In the observation image of Comparative Example 3, the HC layer 12', adhesion 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. Next, the observation image was analyzed using the image processing software ImageJ. This allowed us to determine the first interface length L1 (thick line in Figures 6 and 7) of the interface between the base film 10 (10') and the adhesion layer 21 (21') and the second interface length L2 (thick line in Figures 6 and 7) of the interface between the high refractive index layer 22a (22a') and the low refractive index layer 22b (22b') within a 274 nm image width range in the observation image (cross-sectional view). Then, the ratio of the second interface length L2 to the first interface length L1 (L2 / L1) was calculated. The values ​​are shown in Table 1.

[0136] <Adhesion> The adhesion of the anti-reflective layer was investigated by performing the following first and second tests on each of the anti-reflective films in Example 1, Example 2, and Comparative Examples 1 to 3.

[0137] Exam 1: First, the base film side of the anti-reflective film was fixed to the glass plate. Next, the anti-reflective layer of the anti-reflective film on the glass plate was subjected to an irradiation intensity (integrated illuminance from 290nm to 450nm) of 150mW / cm² at a temperature of 85°C, relative humidity of 45%, and an irradiation intensity of 150mW / cm². 2Under these conditions, the sample was exposed to light for 32.5 hours (accelerated weathering test). This test was conducted using the "iSuper UV Tester SUV-W161" manufactured by Iwasaki Electric Co., Ltd.

[0138] Second Exam: First, using a utility knife, 11 parallel first cuts (2 mm apart) extending linearly in the first direction and 11 parallel second cuts (2 mm apart) extending linearly in the second direction perpendicular to the first direction were made in the anti-reflective layer and adhesion layer of the anti-reflective film on the glass plate after the first test, thereby forming 100 grids. Next, isopropyl alcohol was continuously dropped at a rate of 2 mL / min onto the area of ​​the 100 grids in the anti-reflective film while a polyester wiper (product name "Anticon Gold", manufactured by Sanplatec Co., Ltd.) was slid over the area of ​​the 100 grids under the following conditions: wiper contact surface 20 mm x 20 mm, load 1.5 kg / 20 mm square, sliding speed 50 mm / second, and 1000 reciprocations. Next, of the 100 grids, 1 mm 2 The number of squares where peeling occurred was counted. Next, the peeling rate (%) was calculated by dividing the count by 100.

[0139] The peeling rate was rated as "Excellent" if it was less than 10%, "Good" if it was between 10% and 20%, "Poor" if it was between 20% and 80%, and "Very Poor" if it was 80% or more. The results are shown in Table 1.

[0140] [evaluation] In the anti-reflective film of Comparative Example 1, the HC layer of the base film does not contain particles, and therefore the surface of the base film does not have irregularities caused by particles. In addition, the plasma treatment in the manufacturing process of the anti-reflective film of Comparative Example 1 is, as described above, treatment using inductively coupled plasma with argon-containing gas (Ar-LAICP treatment). Compared to oxygen-LAICP treatment, Ar-LAICP treatment cannot roughen the surface of the base film. In the anti-reflective 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, adhesion of the anti-reflective layer could not be ensured in the anti-reflective film of Comparative Example 1.

[0141] In the anti-reflective film of Comparative Example 2, the HC layer of the base film does not contain particles, and therefore the surface of the base film does not have irregularities caused by particles. In addition, the plasma treatment in the manufacturing process of the anti-reflective film of Comparative Example 2 is ion bombardment (Ar-BB treatment) using capacitively coupled plasma with argon-containing gas, as described above. Compared to oxygen-LAICP treatment, Ar-BB treatment cannot roughen the surface of the base film. In the anti-reflective 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, adhesion of the anti-reflective layer could not be ensured in the anti-reflective film of Comparative Example 2.

[0142] In the anti-reflective film of Comparative Example 3, the HC layer of the base film contains 50% by mass of nanosilica particles. Therefore, as shown in Figure 7, the surface of the base film 10 (the surface on the side of the adhesion layer 21) has irregularities caused by the particles (not shown). In such an anti-reflective film as Comparative Example 3, the irregularities on the surface of the base film are reflected on the surface of the anti-reflective layer (the surface opposite to the base film). Therefore, in the anti-reflective film of Comparative Example 3, the surface roughness Sa of the anti-reflective layer was 5.01 nm, which was large. Consequently, the total reflectance of the anti-reflective film of Comparative Example 3 was 0.46%, which was large.

[0143] In the anti-reflective film of Example 1, the HC layer of the base film does not contain particles. Therefore, as shown in Figure 6, the surface of the base film 10 (the surface on the adhesion layer 21 side) does not have irregularities caused by particles. As a result, the surface roughness Sa of the anti-reflective layer in the anti-reflective film of Example 1 was small, at 1.53 nm. Therefore, the total reflectance of the anti-reflective film of Example 1 was 0.31%, which was smaller than the total reflectance (0.46%) in Comparative Example 3. Furthermore, the plasma treatment in the manufacturing process of the anti-reflective film of Example 1 is, as described above, a treatment using inductively coupled plasma (oxygen-LAICP treatment) with oxygen-containing gas generated by applying high-frequency power to a low-inductance antenna. Compared to Ar-LAICP treatment and Ar-BB treatment, oxygen-LAICP treatment can roughen the surface of the base film with fine irregularities on the order of nanometers. As shown in Figure 6, this is evident on the surface opposite to the base film 10 (the interface between the high refractive index layer 22a and the low refractive index layer 22b) of the two layers formed on the base film 10: the adhesion layer 21 and the high refractive index layer 22a. On this surface, a second set of fine irregularities is formed, starting from the first set of fine irregularities on the surface of the base film 10 and growing from the first set of fine irregularities. Specifically, in the anti-reflective film of Example 1, the ratio of the second interface length L2 to the first interface length L1 (L2 / L1) was 1.10 or greater. Therefore, adhesion of the anti-reflective layer was ensured in the anti-reflective film of Example 1. The same is true in Example 2.

[0144] [Table 1]

[0145] The above invention is provided as an illustrative embodiment of the present invention, but this is merely illustrative and should not be interpreted restrictively. Modifications of the present invention that are obvious to those skilled in the art are included in the claims below. [Industrial applicability]

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

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

Claims

1. An anti-reflective film comprising a base film, an adhesion layer on the base film, and an anti-reflective layer on the adhesion layer, The anti-reflective layer includes, in this order, a high refractive index layer in contact with the adhesion layer and a low refractive index layer on the high refractive index layer. The surface roughness Sa of the surface of the anti-reflective layer opposite to the substrate film is 4.5 nm or less. An anti-reflective film in which, in a cross-sectional view in the thickness direction of the anti-reflective film, 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 base film and the adhesion layer is 1.10 or more.

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

3. The anti-reflective film according to claim 1, wherein the total reflectance of the light irradiated from a standard light source D65 with wavelengths from 380 nm to 780 nm to the anti-reflective layer side is 0.40% or less.

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

5. The anti-reflective film according to any one of claims 1 to 4, wherein the peeling rate of the anti-reflective layer in the second test following the first test is less than 20%. First Exam: First, the base film side of the anti-reflective film is fixed to the glass plate. Next, the anti-reflective layer of the anti-reflective film on the glass plate is subjected to an irradiation intensity (integrated illuminance from 290 nm to 450 nm) of 150 mW / cm² at a temperature of 85°C, relative humidity of 45%, and an irradiation intensity of 150 mW / cm². ２ Under these conditions, light is irradiated for 32.5 hours. Second examination: First, using a cutter knife, eleven parallel first cuts (2 mm apart) extending linearly in a first direction and eleven parallel second cuts (2 mm apart) extending linearly in a second direction perpendicular to the first direction are formed in the anti-reflective layer and the adhesion layer of the anti-reflective film on the glass plate, thereby forming 100 grids. Next, while continuously dropping isopropyl alcohol at a rate of 2 mL / min onto the area of ​​the 100 grids in the anti-reflective film, a polyester wiper is slid under the conditions of a wiper contact surface of 20 mm x 20 mm, a load of 1.5 kg / 20 mm square, a sliding speed of 50 mm / second, and 1000 reciprocations. Next, of the 100 grids, 1 mm ２ Count the number of squares where peeling has occurred. Next, the peeling rate (%) is calculated by dividing the count by 100.

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