Anti-reflective film

Abstract

The present invention relates to an anti-reflective film. An antireflection film (1) is provided with a transparent base film (2), an antireflection layer (4), an antifouling layer (5), and a protective film (6) in this order toward one side in the thickness direction. The antifouling layer (5) contains a silane compound containing a hydrocarbon group having 6-36 carbon atoms (inclusive). The antifouling layer (5) has a water contact angle of 100 DEG or more. The release force of the protective film (6) exceeds 0.060 N / 50 mm.

Description

Technical Field

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

[0002] Conventionally, an antireflection film is sometimes provided on the outer surface of a display such as a liquid crystal display on the viewing side.

[0003] As such an antireflection film, a laminate has been proposed that includes a substrate, a hard coat layer, an antireflection layer, and an antifouling layer containing an alkoxysilane compound having a perfluoropolyether group in this order toward one side in the thickness direction (see, for example, Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. WO2022 / 014575 Pamphlet

[0007] On the other hand, from the viewpoint of protecting the surface of the antireflection film, research is conducted to configure a protective film on the surface of the antireflection film (the surface of the antifouling layer in the antireflection film). In such a case, it is required to improve the adhesion between the antireflection film (antifouling layer) and the protective film.

[0008] Furthermore, the antifouling layer in the antireflection film is also required to have antifouling durability. Specifically, it is required to suppress a decrease in the antifouling property of the antifouling layer even after the stains attached to the antifouling layer are wiped off. Summary of the Invention

[0009] The present invention provides an antireflection film having excellent adhesion between an antifouling layer and a protective film and excellent antifouling durability of the antifouling layer.

[0010] The present invention [1] is an antireflection film comprising, in order toward one side in the thickness direction, a transparent base film, an antireflection layer, an antifouling layer, and a protective film, wherein the antifouling layer contains a silane compound containing a hydrocarbon group having 6 or more and 36 or less carbon atoms, the water contact angle of the antifouling layer is 100° or more, and the peeling force of the protective film exceeds 0.060 N / 50 mm.

[0011] The present invention [2] includes the antireflection film according to the above [1], wherein the dispersion force of the surface free energy of the antifouling layer exceeds 15.5 and is less than 32.4.

[0012] The present invention [3] includes the antireflection film according to [1] or [2] above, wherein the transparent base film comprises a transparent resin film and a cured resin layer disposed on one side in the thickness direction of the transparent resin film.

[0013] The present invention [4] includes the antireflection film according to any one of the above [1] to [3], wherein the antireflection film further comprises a primer layer disposed between the transparent base film and the antireflection layer, and the primer layer is a metal oxide layer.

[0014] The present invention [5] includes the antireflection film according to any one of the above [1] to [4], wherein the antireflection layer comprises a high refractive index layer and a low refractive index layer, the high refractive index layer is a niobium oxide layer, and the low refractive index layer is a silicon dioxide layer.

[0015] Effects of the Invention

[0016] In the antireflection film of the present invention, the antifouling layer contains a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms, the antifouling layer has a water contact angle of 100° or greater, and the peel strength of the protective film exceeds 0.060 N / 50 mm. Consequently, the antifouling layer exhibits excellent adhesion to the protective film and excellent antifouling durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A cross-sectional view showing one embodiment of the antireflection film of the present invention.

[0018] Figure 2 2A to 2E in FIG. 2 show one embodiment of a method for producing an antireflection film. Figure 2 In the figure, 2A represents the first step of preparing a transparent base material film; 2B represents the second step of configuring a primer layer on one side of the thickness direction of the transparent base material film; 2C represents the third step of configuring an anti-reflection layer on one side of the thickness direction of the primer layer; 2D represents the fourth step of configuring an anti-fouling layer on one side of the thickness direction of the anti-reflection layer; 2E represents the fifth step of configuring a protective film on one side of the thickness direction of the anti-fouling layer.

[0019] Description of Reference Numerals

[0020] 1: Antireflection film; 2: Transparent substrate film; 3: Primer layer; 4: Antireflection layer; 5: Antifouling layer; 6: Protective film; 21: Transparent resin film; 22: Cured resin layer; 41: First high refractive index layer; 42: First low refractive index layer; 43: Second high refractive index layer; 44: Second low refractive index layer. DETAILED DESCRIPTION

[0021] Reference Figure 1 One embodiment of the antireflection film of the present invention will be described.

[0022] Figure 1In the figure, the vertical direction on the paper is the vertical direction (thickness direction), the upper side of the paper is the upper side (one side in the thickness direction), and the lower side of the paper is the lower side (the other side in the thickness direction). In addition, the left-right direction and the depth direction on the paper are plane directions perpendicular to the vertical direction. Specifically, according to the direction arrows in each figure.

[0023] <Anti-reflective film>

[0024] The antireflection film 1 has a film shape (including a sheet shape) with a predetermined thickness. The antireflection film 1 extends in a plane direction perpendicular to the thickness direction. The antireflection film 1 has a flat upper surface and a flat lower surface.

[0025] like Figure 1 As shown, the antireflection film 1 includes, in order toward one side in the thickness direction, a transparent base film 2, a primer layer 3, an antireflection layer 4, an antifouling layer 5, and a protective film 6. Specifically, the antireflection film 1 includes, in order toward one side in the thickness direction, the transparent base film 2, the primer layer 3 directly disposed on the upper surface (one surface in the thickness direction) of the transparent base film 2, the antireflection layer 4 directly disposed on the upper surface (one surface in the thickness direction) of the primer layer 3, the antifouling layer 5 directly disposed on the upper surface (one surface in the thickness direction) of the antireflection layer 4, and the protective film 6 directly disposed on the upper surface (one surface in the thickness direction) of the antifouling layer 5.

[0026] The total light transmittance (JIS K-7105) of the antireflection film 1 is, for example, 80% to 100%, preferably 85% to 100%, more preferably 88% to 100%, and further preferably 90% to 100%.

[0027] The thickness of the antireflection film 1 is not particularly limited, but is, from the viewpoint of strength and handleability, for example, 5 μm to 500 μm, preferably 10 μm to 300 μm, and more preferably 20 μm to 200 μm.

[0028] <Transparent base film>

[0029] The transparent base film 2 ensures the mechanical strength of the antireflection film 1 .

[0030] The transparent base film 2 is the bottom layer of the antireflection film 1. The transparent base film 2 includes a transparent resin film 21. Furthermore, the transparent base film 2 may further include a cured resin layer 22 disposed on one side in the thickness direction of the transparent base film 2, as needed. The transparent base film 2 preferably includes the transparent resin film 21 and the cured resin layer 22 disposed on one side in the thickness direction of the transparent resin film 21 (preferably on one side in the thickness direction).

[0031] The total light transmittance (JIS K-7105) of the transparent base material film 2 is, for example, 80% to 100%, preferably 85% to 100%, more preferably 88% to 100%, and further preferably 90% to 100%.

[0032] The thickness of the transparent base film 2 is not particularly limited, but is, from the viewpoint of strength and handleability, for example, 5 μm to 300 μm, preferably 10 μm to 250 μm, more preferably 20 μm to 200 μm, further preferably 30 μm to 170 μm, and particularly preferably 50 μm to 150 μm.

[0033] [Transparent resin film]

[0034] The transparent resin film 21 has a film shape (including a sheet shape) and is, for example, a transparent resin film having flexibility.

[0035] As the material of the transparent resin film 21, for example, cellulose resin, polyester resin, (meth) acrylic resin (acrylic resin and / or methacrylic resin), olefin resin, polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, polystyrene resin, norbornene resin, and polyvinyl alcohol resin can be listed. As the polyester resin, for example, polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate can be listed. As the polyolefin resin, for example, polyethylene, polypropylene, and cycloolefin polymer (COP) can be listed. As the cellulose resin, for example, triacetyl cellulose (TAC) can be listed. As the material of the transparent resin film 21, from the viewpoint of transparency, heat resistance and mechanical strength, cellulose resin is preferably listed. As the material of the transparent resin film 21, triacetyl cellulose (TAC) is more preferably listed.

[0036] The material of the transparent resin film 21 can be used alone or in combination of two or more.

[0037] The total light transmittance (JIS K-7105) of the transparent resin film 21 is, for example, 80% to 100%, preferably 85% to 100%, more preferably 88% to 100%, and further preferably 90% to 100%.

[0038] The thickness of the transparent resin film 21 is not particularly limited, but is, from the viewpoint of strength and handleability, for example, 5 μm to 300 μm, preferably 10 μm to 250 μm, more preferably 20 μm to 200 μm, further preferably 30 μm to 150 μm, and particularly preferably 50 μm to 100 μm.

[0039] In addition, the thickness of the transparent resin film 21 can be measured using, for example, a film thickness meter.

[0040] [Cured resin layer]

[0041] The cured resin layer 22 improves the mechanical properties of the antireflection film 1. The cured resin layer 22 is in contact with the upper surface (one surface in the thickness direction) of the transparent resin film 21.

[0042] Examples of the cured resin layer 22 include a hard coat layer. The hard coat layer prevents the antireflection film 1 from being damaged.

[0043] The cured resin layer 22 is, for example, a cured product of a curable resin composition.

[0044] The curable resin composition contains a curable resin.

[0045] Examples of curable resins include polyester resins, acrylic urethane resins, acrylic resins (excluding acrylic urethane resins), urethane resins (excluding acrylic urethane resins), amide resins, silicone resins, epoxy resins, and melamine resins. Examples of curable resins include acrylic resins (excluding acrylic urethane resins) and acrylic urethane resins. More preferably, curable resins include acrylic resins (excluding acrylic urethane resins).

[0046] The curable resins may be used alone or in combination of two or more.

[0047] In addition, as a curable resin composition, for example, a UV-curable resin composition and a thermosetting resin composition can be listed. As a curable resin composition, from the viewpoint of manufacturing efficiency, a UV-curable resin composition is preferably used. The UV-curable resin composition contains at least one selected from the group consisting of a UV-curable monomer, a UV-curable oligomer, and a UV-curable polymer. As a specific example of a UV-curable resin composition, a hard coat layer forming composition described in Japanese Patent Application Laid-Open No. 2016-179686 can be listed.

[0048] The curable resin composition preferably contains particles. If the curable resin composition contains particles, anti-glare properties can be imparted to the cured resin layer 22 and the peeling force of the protective film 6 can be improved by adjusting the surface roughness (described later).

[0049] Examples of the particles include inorganic particles and organic particles.

[0050] Examples of the inorganic particles include inorganic oxide particles. Examples of materials for the inorganic oxide particles include silicon dioxide, aluminum oxide, titanium dioxide, zirconium oxide, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. Silicon dioxide is preferably used as the material for the inorganic oxide particles.

[0051] The average particle diameter of the inorganic particles is, for example, 1 nm to 100 nm, preferably 10 nm to 70 nm, and more preferably 30 nm to 50 nm.

[0052] The average particle size is determined as a D50 value (cumulative 50% median diameter) based on, for example, a particle size distribution determined by a particle size distribution measurement method using a laser scattering method (the same applies hereinafter).

[0053] Examples of materials for the organic particles include polymethyl methacrylate (eg, cross-linked polymethyl methacrylate), polystyrene, polyurethane, acrylic acid / styrene copolymer, benzoguanamine, melamine, and polycarbonate. Preferably, polymethyl methacrylate is used as the material for the organic particles.

[0054] The average particle diameter of the organic particles is, for example, 0.1 μm to 20 μm, preferably 1 μm to 10 μm, and more preferably 2 μm to 5 μm.

[0055] The content ratio of the particles is, for example, 50 to 80 parts by mass, or preferably 55 to 70 parts by mass, relative to 100 parts by mass of the total amount of the curable resin and the particles.

[0056] The particles may be used alone or in combination of two or more types. Preferably, inorganic particles and organic particles are used in combination.

[0057] Furthermore, when the curable resin composition is an ultraviolet curable resin composition, the curable resin composition preferably contains a photopolymerization initiator at an appropriate ratio.

[0058] Furthermore, the curable resin composition may contain additives in appropriate proportions as needed. Examples of the additives include a leveling agent, a thixotropic agent, and an antistatic agent.

[0059] The curable resin composition can also be diluted with a solvent to prepare a diluted curable resin composition. Examples of the solvent include butyl acetate, ethyl acetate, toluene, 1-methoxy-2-propanol, and cyclopentanone. These solvents can be used alone or in combination of two or more.

[0060] The solid content concentration of the diluted curable resin composition is, for example, 20% by mass to 50% by mass.

[0061] As will be described in detail below, the cured resin layer 22 can be formed by applying a curable resin composition (a diluted curable resin composition) on one surface in the thickness direction of the transparent resin film 21 and drying and curing the composition as needed.

[0062] The thickness of the cured resin layer 22 is, for example, 0.1 μm to 15 μm, preferably 0.5 μm to 12 μm, more preferably 1 μm to 10 μm, and further preferably 3 μm to 8 μm.

[0063] <Primer layer>

[0064] The primer layer 3 improves the adhesion between the transparent base film 2 and the antireflection layer 4. The primer layer 3 is disposed between the transparent base film 2 and the antireflection layer 4. The primer layer 3 is in contact with the upper surface (one surface in the thickness direction) of the transparent base film 2.

[0065] Examples of the material of the primer layer 3 include metals, and examples of the metals include nickel, chromium, indium, aluminum, tin, gold, silver, platinum, zinc, titanium, tungsten, zirconium, and palladium.

[0066] In addition, examples of the material of the primer layer 3 include alloys of the above-mentioned metals and oxides of the above-mentioned metals.

[0067] Examples of the above-mentioned metal oxides include indium-containing conductive oxides, antimony-containing conductive oxides, and zinc-containing conductive oxides. Examples of indium-containing conductive oxides include indium-tin composite oxide (ITO), indium-zinc composite oxide (IZO), indium-gallium composite oxide (IGO), and indium-gallium-zinc composite oxide (IGZO). Examples of antimony-containing conductive oxides include antimony-tin composite oxide (ATO). Examples of zinc-containing conductive oxides include zinc-aluminum composite oxide (AZO).

[0068] In addition, examples of the material of the primer layer 3 include semimetals (eg, silicon) and oxides thereof.

[0069] As the material for the primer layer 3, from the viewpoint of further improving the adhesion between the transparent base film 2 and the antireflection layer 4, a metal oxide is preferably used. In other words, the primer layer 3 is preferably a metal oxide layer. As the material for the primer layer 3, an indium-containing conductive oxide is more preferably used. As the material for the primer layer 3, indium tin composite oxide (ITO) is further preferably used.

[0070] In the indium tin composite oxide (ITO) serving as the material for the primer layer 3, the content of tin oxide relative to the total amount of indium oxide and tin oxide is, for example, 1% by mass to 50% by mass, preferably 3% by mass to 45% by mass, more preferably 5% by mass to 20% by mass, and even more preferably 8% by mass to 15% by mass.

[0071] As will be described in detail below, the primer layer 3 is preferably formed by sputtering. That is, the primer layer 3 is preferably a sputtered layer.

[0072] The thickness of the primer layer 3 is, for example, 0.1 nm to 30.0 nm, preferably 0.5 nm to 20.0 nm, more preferably 1.0 nm to 15.0 nm, further preferably 2.0 nm to 10.0 nm, and particularly preferably 3.0 nm to 8.0 nm.

[0073] When the thickness of the primer layer 3 is within the above range, the adhesion between the transparent base material film 2 and the antireflection layer 4 can be improved.

[0074] <Anti-reflection layer>

[0075] The antireflection layer 4 is in contact with the upper surface (one surface in the thickness direction) of the primer layer 3 .

[0076] The anti-reflection layer 4 has two or more layers having different refractive indices. Specifically, the anti-reflection layer has high refractive index layers with relatively large refractive indexes and low refractive index layers with relatively small refractive indexes alternately in the thickness direction. In the anti-reflection layer, the net reflected light intensity is attenuated by the interference effect between the reflected light at multiple interfaces in the multiple thin layers (high refractive index layers, low refractive index layers) contained therein. In addition, in the anti-reflection layer, by adjusting the optical film thickness (the product of the refractive index and the thickness) of each thin layer, an interference effect that attenuates the reflected light intensity can be exhibited. In the following description, the case where the anti-reflection layer 4 has two high refractive index layers and two low refractive index layers is described in detail.

[0077] That is, the anti-reflection layer 4 includes, in order toward one side in the thickness direction, a first high refractive index layer 41, a first low refractive index layer 42, a second high refractive index layer 43, and a second low refractive index layer 44. Specifically, the anti-reflection layer 4 includes, in order toward one side in the thickness direction, the first high refractive index layer 41, the first low refractive index layer 42 directly disposed on the upper surface (one surface in the thickness direction) of the first high refractive index layer 41, the second high refractive index layer 43 directly disposed on the upper surface (one surface in the thickness direction) of the first low refractive index layer 42, and the second low refractive index layer 44 directly disposed on the upper surface (one surface in the thickness direction) of the second high refractive index layer 43.

[0078] The first high refractive index layer 41 and the second high refractive index layer 43 are each formed of a high refractive index material having a refractive index of preferably 1.9 or greater at a wavelength of 550 nm. As high refractive index materials, from the perspective of balancing high refractive index and low absorption of visible light, examples include niobium oxide (Nb2O5), titanium oxide, zirconium oxide, indium tin oxide (ITO), and antimony-doped tin oxide (ATO). As a high refractive index material, niobium oxide (Nb2O5) is preferably listed. In other words, it is preferred that the material of the first high refractive index layer 41 and the material of the second high refractive index layer 43 are both niobium oxide (Nb2O5). In other words, it is preferred that the first high refractive index layer 41 and the second high refractive index layer 43 are both niobium oxide layers.

[0079] The first low-refractive index layer 42 and the second low-refractive index layer 44 are respectively formed by a low-refractive index material having a refractive index of preferably less than 1.6 at a wavelength of 550nm. As a low-refractive index material, from the viewpoint of taking into account the low absorptivity of low refractive index and visible light, for example, silicon dioxide (SiO2) and magnesium fluoride can be listed. As a low-refractive index material, silicon dioxide (SiO2) is preferably listed. In other words, preferably, the material of the first low-refractive index layer 42 and the material of the second low-refractive index layer 44 are both silicon dioxide (SiO2). In other words, preferably, the first low-refractive index layer 42 and the second low-refractive index layer 44 are both silicon dioxide layers.

[0080] The thickness of the first high refractive index layer 41 is, for example, 1 nm to 50 nm, preferably 5 nm to 30 nm, and more preferably 8 nm to 20 nm.

[0081] The thickness of the first low-refractive index layer 42 is, for example, 1 nm to 50 nm, preferably 10 nm to 40 nm, and more preferably 15 nm to 25 nm.

[0082] The second high refractive index layer 43 is thicker than the first high refractive index layer 41 , and is, for example, 60 nm to 200 nm, preferably 80 nm to 150 nm, and more preferably 90 nm to 110 nm.

[0083] The second low-refractive-index layer 44 is thicker than the first low-refractive-index layer 42 , and is, for example, 60 nm to 200 nm, preferably 65 nm to 150 nm, and more preferably 70 nm to 90 nm.

[0084] The ratio of the thickness of the second high refractive index layer 43 to the thickness of the first high refractive index layer 41 (thickness of the second high refractive index layer 43 / thickness of the first high refractive index layer 41 ) is, for example, 3.0 to 15.0, preferably 4.0 to 10.0, and more preferably 6.0 to 8.0.

[0085] The ratio of the thickness of the second low refractive index layer 44 to the thickness of the first low refractive index layer 42 (thickness of the second low refractive index layer 44 / thickness of the first low refractive index layer 42 ) is, for example, 1.5 to 10.0, preferably 2.0 to 8.0, and more preferably 3.0 to 5.0.

[0086] As will be described in detail below, the antireflection layer 4 is preferably formed by sputtering. That is, the antireflection layer 4 is preferably a sputtered layer.

[0087] The thickness of the antireflection layer 4 is, for example, 100 nm to 300 nm, preferably 150 nm to 250 nm, and more preferably 200 nm to 230 nm.

[0088] <Antifouling layer>

[0089] The antifouling layer 5 prevents the adhesion of stains (eg, dirt, fingerprints) and is in contact with the upper surface (one surface in the thickness direction) of the antireflection layer 4 .

[0090] The antifouling layer 5 is formed from a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms. In other words, the antifouling layer 5 contains a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms. The antifouling layer 5 is preferably formed from a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms. If the antifouling layer 5 contains a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms, the adhesion between the antifouling layer 5 and the protective film 6 can be improved. In addition, even after stains attached to the antifouling layer 5 are wiped off, the antifouling properties of the antifouling layer 5 can be suppressed from decreasing (excellent antifouling durability).

[0091] Among the silane compounds containing a hydrocarbon group having 6 to 36 carbon atoms, examples of the hydrocarbon group having 6 to 36 carbon atoms include hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontanyl, tritriacontanyl, tetratriacontanyl, pentatriacontanyl, and hexatriacontanyl. The sliding resistance of the antifouling layer 5 tends to improve as the number of carbon atoms increases. The number of carbon atoms is preferably 12 or more, and more preferably 18 or more.

[0092] Among the silane compounds containing a hydrocarbon group having 6 to 36 carbon atoms, examples of the silane compound include alkoxysilane compounds, chlorosilane compounds, hydroxysilane compounds, and triacetoxysilane compounds. Preferred silane compounds include alkoxysilane compounds.

[0093] Examples of the alkoxysilane compound include trialkoxysilane compounds and alkyldialkoxysilane compounds.

[0094] Examples of the trialkoxysilane compound include a trimethoxysilane compound, a triethoxysilane compound, a tripropoxysilane compound, and a tributoxysilane compound.

[0095] Examples of the alkyldialkoxysilane compound include a methyldimethoxysilane compound, an ethyldimethoxysilane compound, a methyldiethoxysilane compound, an ethyldiethoxysilane compound, and a methyldipropoxysilane compound.

[0096] As the alkoxysilane compound, preferably, a trialkoxysilane compound is used.

[0097] Specific examples of the silane compound containing a hydrocarbon group having 6 to 36 carbon atoms include octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, and octadecyltrimethoxysilane. Preferably, octadecyltrimethoxysilane is used as the silane compound containing a hydrocarbon group having 6 to 36 carbon atoms.

[0098] The antifouling layer 5 is formed by a method described later.

[0099] The water contact angle (pure water contact angle) of the outer surface (exposed surface) of the antifouling layer 5 is 100° or more, preferably 102° or more, more preferably 105° or more, further preferably 110° or more, and for example, 130° or less.

[0100] When the water contact angle of the antifouling layer 5 is equal to or greater than the above lower limit, the antifouling property and antifouling durability can be improved.

[0101] On the other hand, if the water contact angle of the antifouling layer 5 is less than the above lower limit, the antifouling property and antifouling durability are reduced.

[0102] The water contact angle of the antifouling layer 5 can be adjusted to the above-mentioned range by adjusting the material of the antifouling layer 5 , the thickness of the antifouling layer 5 , and the method for forming the antifouling layer 5 .

[0103] In addition, the method for measuring the water contact angle of the antifouling layer 5 will be described in detail in the examples described later.

[0104] Furthermore, the dispersion force of the surface free energy of the antifouling layer 5 is, from the viewpoint of improving the adhesion between the antifouling layer 5 and the protective film 6, for example, greater than 15.5, preferably 20.0 or greater, more preferably 22.0 or greater, and even more preferably 24.0 or greater. Furthermore, from the viewpoint of improving the antifouling durability of the antifouling layer 5, for example, less than 32.4, preferably 30.0 or less, more preferably 28.0 or less, further preferably 26.0 or less, and particularly preferably 25.0 or less.

[0105] In addition, with respect to the orientation force of the surface free energy of the antifouling layer 5, for example, from the viewpoint of improving the adhesion between the antifouling layer 5 and the protective film 6, it is, for example, 0.1 or more, preferably 0.2 or more, more preferably 0.5 or more, further preferably 1.0 or more, particularly preferably 3.0 or more, and most preferably 4.0 or more. Furthermore, from the viewpoint of improving the antifouling durability of the antifouling layer 5, it is, for example, 6.0 or less, preferably 5.0 or less.

[0106] Furthermore, the hydrogen bonding force of the surface free energy of the antifouling layer 5 is, for example, 0.5 or less, preferably 0.1 or less, and more preferably 0.

[0107] In addition, the method for measuring the surface free energy (dispersion force, orientation force, and hydrogen bonding force) of the antifouling layer 5 will be described in detail in the examples to be described later.

[0108] The thickness of the antifouling layer 5 is, for example, 1 nm to 100 nm, preferably 2 nm to 50 nm, more preferably 3 nm to 20 nm, and further preferably 4 nm to 10 nm.

[0109] <Protective film>

[0110] The protective film 6 protects the surface (one surface in the thickness direction) of the antifouling layer 5. The protective film 6 is in contact with the upper surface (one surface in the thickness direction) of the antifouling layer 5. The protective film 6 is the uppermost layer of the antireflection film 1.

[0111] The protective film 6 includes an adhesive layer 31 and a base layer 32 in this order toward one side in the thickness direction. Specifically, the protective film 6 includes an adhesive layer 31 and a base layer 32 directly disposed on the upper surface (one side in the thickness direction) of the adhesive layer 31.

[0112] (Adhesive layer)

[0113] The adhesive layer 31 is formed of an adhesive composition.

[0114] The adhesive composition comprises a base polymer. Examples of the base polymer include acrylic acid polymers, silicone polymers, polyester polymers, polyurethane polymers, polyamide polymers, polyvinyl ether polymers, vinyl acetate / vinyl chloride copolymers, modified polyolefin polymers, epoxy polymers, fluorine polymers, and rubber polymers (e.g., natural rubber and synthetic rubber). From the perspective of adhesiveness and optical transparency, acrylic acid polymers may be used as the base polymer.

[0115] The acrylic polymer is a polymer containing a monomer component of an alkyl (meth)acrylate.

[0116] Examples of the alkyl (meth)acrylate include alkyl (meth)acrylates having an alkyl group with 1 to 20 carbon atoms. Examples of the alkyl (meth)acrylates having an alkyl group with 1 to 20 carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, and (meth)acrylate. Nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, isotridecyl (meth)acrylate, tetradecyl (meth)acrylate, isotetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, isooctadecyl (meth)acrylate, and nonadecyl (meth)acrylate. Preferred examples of the alkyl (meth)acrylate include 2-ethylhexyl (meth)acrylate. More preferred examples of the alkyl (meth)acrylate include 2-ethylhexyl acrylate.

[0117] The content ratio of the alkyl (meth)acrylate is, for example, 50 to 100 mass %, preferably 80 to 100 mass %, and more preferably 90 to 98 mass % based on the monomer components.

[0118] The (meth)acrylic acid alkyl esters may be used alone or in combination of two or more.

[0119] The monomer component may also contain a comonomer that is copolymerizable with the (meth)acrylate. Examples of the comonomer include monomers having polar groups (polar group-containing monomers). Polar group-containing monomers contribute to the introduction of crosslinking points into the acrylic polymer, the securing of the cohesive force of the acrylic polymer, and the modification of the acrylic polymer.

[0120] Examples of the polar group-containing monomer include a hydroxyl group-containing monomer, a monomer having a nitrogen atom-containing ring, and a carboxyl group-containing monomer.

[0121] Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate.

[0122] Examples of the monomer having a nitrogen atom-containing ring include N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-(meth)acryloyl-2-pyrrolidone, N-(meth)acryloylpiperidine, N-(meth)acryloylpyrrolidine, N-vinylmorpholine, N-vinyl-3-morpholinone, N-vinyl-2-caprolactam, N-vinyl-1,3-oxazin-2-one, N-vinyl-3,5-morpholinedione, N-vinylpyrazole, N-vinylisoxazole, N-vinylthiazole, and N-vinylisothiazole.

[0123] Examples of the carboxyl group-containing monomer include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid.

[0124] As the polar group-containing monomer, preferably a hydroxyl group-containing monomer is used. As the polar group-containing monomer, more preferably 2-hydroxyethyl (meth)acrylate is used. As the polar group-containing monomer, even more preferably 2-hydroxyethyl acrylate is used.

[0125] The content ratio of the copolymerizable monomer is, for example, 0 mass % to 50 mass %, preferably 0 mass % to 20 mass %, and more preferably 2 mass % to 10 mass % based on the monomer components.

[0126] The copolymerizable monomers can be used alone or in combination of two or more.

[0127] The monomer component may contain other copolymerizable monomers. Examples of other copolymerizable monomers include acid anhydride monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, epoxy group-containing monomers, cyano group-containing monomers, amide group-containing monomers, monomers having a succinimide skeleton, maleimides, itaconimides, alkoxy group-containing monomers, vinyl esters, vinyl ethers, and aromatic vinyl compounds.

[0128] The content ratio of other copolymerizable monomers is, for example, 10 mass % or less, preferably 5 mass % or less, more preferably 1 mass % or less, and further preferably 0 mass % based on the monomer components.

[0129] Other copolymerizable monomers may be used alone or in combination of two or more.

[0130] Acrylic polymers can be formed by polymerizing the aforementioned monomer components. Examples of polymerization methods include solution polymerization, bulk polymerization, and emulsion polymerization, with solution polymerization being preferred. In solution polymerization, for example, the monomer components and a polymerization initiator are combined in a solvent (e.g., ethyl acetate) to prepare a reaction solution, which is then heated. The monomer components in the reaction solution then undergo a polymerization reaction, yielding an acrylic polymer solution containing the acrylic polymer.

[0131] Examples of the polymerization initiator include azo-based polymerization initiators and peroxide-based polymerization initiators. Examples of the azo-based polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, 2,2'-azobis(2-methylpropionic acid)dimethyl ester, 4,4'-azobis-4-cyanovaleric acid, azobisisovaleronitrile, 2,2'-azobis(2-amidinopropane) dihydrochloride, 2,2'-azobis[2-(5-methyl-2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate, and 2,2'-azobis(N,N'-dimethyleneisobutylamidine) dihydrochloride. Examples of peroxide-based polymerization initiators include dibenzoyl peroxide, t-butyl permaleate, and lauroyl peroxide. Preferred polymerization initiators include azo-based polymerization initiators. More preferred polymerization initiators include 2,2'-azobisisobutyronitrile.

[0132] The amount of the polymerization initiator used is, for example, 0.05 to 1 part by mass relative to 100 parts by mass of the monomer component.

[0133] As reaction conditions, the reaction temperature is, for example, 50° C. to 100° C. The reaction time is, for example, 1 hour to 15 hours.

[0134] In this way, an acrylic polymer was obtained.

[0135] Furthermore, the acrylic polymer (acrylic polymer solution) may be diluted with a known solvent (eg, toluene, acetylacetone).

[0136] The weight average molecular weight (polystyrene-equivalent weight average molecular weight) of the acrylic polymer is, for example, 50,000 to 2,000,000, preferably 70,000 to 1,800,000, more preferably 100,000 to 1,500,000, and even more preferably 200,000 to 1,000,000.

[0137] Furthermore, a crosslinking agent may be added to the acrylic polymer solution to introduce a crosslinked structure into the acrylic polymer. In such a case, the PSA composition contains the crosslinking agent.

[0138] Examples of the crosslinking agent include isocyanate crosslinking agents, epoxy crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, carbodiimide crosslinking agents, and metal chelate crosslinking agents. Preferred crosslinking agents include isocyanate crosslinking agents.

[0139] As the isocyanate-based crosslinking agent, a polyisocyanate having two or more isocyanate groups in one molecule can be used. Examples of the isocyanate-based crosslinking agent include aliphatic isocyanates (e.g., butylene diisocyanate, butylene diisocyanate), alicyclic isocyanates (e.g., cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate), aromatic isocyanates (e.g., 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, and xylylenediisocyanate), and modified forms thereof (isocyanurate-modified forms, trimethylolpropane-modified forms).

[0140] As the isocyanate-based crosslinking agent, preferably, a trimethylolpropane-modified toluene diisocyanate is used.

[0141] The amount of the crosslinking agent used is, for example, 1 to 15 parts by mass, preferably 2 to 10 parts by mass, and more preferably 3 to 6 parts by mass, relative to 100 parts by mass of the acrylic polymer.

[0142] Furthermore, the adhesive composition may contain a polymerization catalyst, a crosslinking catalyst, a silane coupling agent, an adhesion-imparting agent, a plasticizer, a softener, an anti-degradation agent, a filler, a colorant, an ultraviolet absorber, an antioxidant, a surfactant, an antistatic agent, and the like as needed.

[0143] As will be described in detail below, the adhesive layer 31 is formed of an adhesive composition.

[0144] The thickness of the adhesive layer 31 is, for example, 5 μm to 50 μm, preferably 10 μm to 40 μm, and more preferably 15 μm to 30 μm.

[0145] (Base material layer)

[0146] The base material layer 32 has a film shape (including a sheet shape).

[0147] Examples of the material for the base layer 32 include the same materials as those for the transparent resin film 21. A preferred material for the base layer 32 is polyester resin, and a more preferred material for the base layer 32 is polyethylene terephthalate (PET).

[0148] The thickness of the base material layer 32 is not particularly limited, but is, from the viewpoint of strength and handleability, for example, 5 μm to 100 μm, preferably 10 μm to 80 μm, and more preferably 20 μm to 60 μm.

[0149] (Manufacturing of protective film)

[0150] The protective film 6 is obtained by applying the adhesive composition to the other surface in the thickness direction of the base material layer 32 and drying it as needed.

[0151] Examples of coating methods include roll coating, lick roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, rod coating, knife coating, air knife coating, curtain coating, die lip coating, and die coating.

[0152] As drying conditions, the drying temperature is, for example, 40° C. to 200° C., and preferably 50° C. to 180° C. The drying time is, for example, 5 seconds to 20 minutes, and preferably 5 seconds to 10 minutes.

[0153] Furthermore, when the pressure-sensitive adhesive composition contains a crosslinking agent, it is preferred that a crosslinking reaction proceeds by heating or aging simultaneously with or after the drying.

[0154] As heating conditions, the heating temperature is, for example, 20° C. to 160° C. The heating time is, for example, 1 minute to 7 days.

[0155] Thus, the protective film 6 is produced.

[0156] (Properties of protective film)

[0157] The thickness of the protective film 6 is, for example, 3 μm to 200 μm, preferably 10 μm to 100 μm, and more preferably 20 μm to 50 μm.

[0158] The peeling force of the protective film 6 exceeds 0.060 N / 50 mm, preferably 0.100 N / 50 mm or more, more preferably 0.120 N / 50 mm or more, further preferably 0.140 N / 50 mm or more, particularly preferably 0.160 N / 50 mm or more, and is, for example, 0.500 N / 50 mm or less.

[0159] When the peeling strength of the protective film 6 exceeds the above lower limit (or is equal to or greater than the above lower limit), the adhesion between the antifouling layer 5 and the protective film 6 can be improved.

[0160] On the other hand, when the peeling strength of the protective film 6 is equal to or less than the above lower limit (or less than the above lower limit), the adhesion between the antifouling layer 5 and the protective film 6 is reduced.

[0161] The peeling strength of the protective film 6 can be adjusted to the above range by adjusting the formulation of the adhesive composition, the thickness of the adhesive layer 31 , the material of the antifouling layer 5 , and the method for forming the antifouling layer 5 .

[0162] In addition, the method of measuring the peeling force of the protective film 6 will be described in detail in the examples to be described later.

[0163] <Method for producing antireflection film>

[0164] Reference Figure 2 2A to 2E, a method for manufacturing the antireflection film 1 will be described.

[0165] The method for producing an antireflection film 1 includes a first step of preparing a transparent base film 2, a second step of disposing a primer layer 3 on one surface in the thickness direction of the transparent base film 2, a third step of disposing an antireflection layer 4 on one surface in the thickness direction of the primer layer 3, a fourth step of disposing an antifouling layer 5 on one surface in the thickness direction of the antireflection layer 4, and a fifth step of disposing a protective film 6 on one surface in the thickness direction of the antifouling layer 5. In this production method, the layers are sequentially disposed, for example, in a roll-to-roll manner.

[0166] [First process]

[0167] In the first process, Figure 2 As shown in FIG2A , first, a transparent base film 2 is prepared.

[0168] Specifically, a curable resin composition (a diluted curable resin composition) is applied to one surface in the thickness direction of the transparent resin film 21 , dried as needed, and then cured by ultraviolet irradiation or heating.

[0169] As drying conditions, the drying temperature is, for example, 40° C. to 100° C., and preferably 60° C. to 90° C. The drying time is, for example, 10 seconds to 240 seconds, and preferably 30 seconds to 120 seconds.

[0170] Thus, the cured resin layer 22 is arranged (formed) on one surface in the thickness direction of the transparent resin film 21. The transparent base material film 2 is prepared as described above.

[0171] [Second step]

[0172] In the second process, Figure 2 As shown in FIG2B , a primer layer 3 is arranged on one surface in the thickness direction of the transparent base film 2 .

[0173] In order to arrange the primer layer 3 on one side of the thickness direction of the transparent base material film 2, from the viewpoint of the close adhesion between the transparent base material film 2 and the primer layer 3, first, the surface of the transparent base material film 2 is subjected to, for example, a surface treatment as needed. Examples of the surface treatment include corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, glow treatment, and saponification treatment. As the surface treatment, plasma treatment is preferably used.

[0174] Examples of plasma treatment include argon plasma treatment and oxygen plasma treatment. Preferably, argon plasma treatment is used. The output power of the plasma treatment is, for example, 0.1 kW to 2.0 WkW.

[0175] Furthermore, as a method for disposing the primer layer 3 on one side of the thickness direction of the transparent base material film 2, for example, a dry coating method and a wet coating method can be cited. As a method for disposing the primer layer 3 on one side of the thickness direction of the transparent base material film 2, a dry coating method is preferably cited. As a dry coating method, for example, a vacuum evaporation method, a sputtering method, and a CVD method can be cited. As a dry coating method, a sputtering method is preferably cited.

[0176] In the sputtering method, a target (material for the primer layer 3) and a transparent substrate film 2 are arranged opposite each other in a vacuum chamber, a sputtering gas is supplied, and a voltage is applied from a power supply, thereby accelerating the gas ions and irradiating the target, driving the target material from the target surface, and depositing each layer of the target material on the surface of the transparent substrate film 2 in sequence.

[0177] As the sputtering gas, for example, an inert gas (such as argon) can be cited. In addition, a reactive gas such as oxygen can be used in combination as needed. When a reactive gas is used in combination, the flow ratio (sccm) of the reactive gas is not particularly limited, and is, for example, 0.1 flow % to 100 flow % relative to the total flow ratio of the sputtering gas and the reactive gas.

[0178] The gas pressure during sputtering is, for example, 0.1 Pa to 1.0 Pa.

[0179] The power source may be, for example, any one of a DC power source, an AC power source, an MF power source, and an RF power source, or a combination thereof.

[0180] The discharge power is, for example, 1.0 kW to 10.0 kW, preferably 3.0 kW to 6.0 kW.

[0181] The film-forming temperature (temperature of the transparent base film 2 when forming the primer layer 3 ) is, for example, -50.0°C to 30.0°C, preferably -30.0°C to 20.0°C, more preferably -20.0°C to 10.0°C, and further preferably -15.0°C to 0.0°C.

[0182] Thus, the primer layer 3 is arranged on one surface in the thickness direction of the transparent base material film 2 .

[0183] [Third Process]

[0184] In the third process, Figure 2 As shown in FIG2C , an antireflection layer 4 is disposed on one side in the thickness direction of the primer layer 3. Specifically, a first high refractive index layer 41, a first low refractive index layer 42, a second high refractive index layer 43, and a second low refractive index layer 44 are disposed in sequence on one side in the thickness direction of the primer layer 3.

[0185] As a method for disposing the antireflection layer 4 on one surface in the thickness direction of the primer layer 3, for example, there can be mentioned the same method as the method for disposing the primer layer 3 on one surface in the thickness direction of the transparent base material film 2. As a method for disposing the antireflection layer 4 on one surface in the thickness direction of the primer layer 3, a sputtering method is preferably mentioned.

[0186] The sputtering method is performed based on the same procedure as the sputtering method in the above-mentioned second step.

[0187] The sputtering gas, gas pressure, power supply, and film formation temperature in the sputtering method are the same as those in the second step described above.

[0188] The discharge power is, for example, 1.0 kW to 50.0 kW, and preferably 15.0 kW to 30.0 kW.

[0189] Thus, the antireflection layer 4 is arranged on one surface in the thickness direction of the primer layer 3 .

[0190] [Fourth Process]

[0191] In the fourth step, Figure 2 As shown in FIG2D , the antifouling layer 5 is arranged on one surface of the antireflection layer 4 in the thickness direction.

[0192] Examples of a method for disposing the antifouling layer 5 on one surface in the thickness direction of the antireflection layer 4 include the same method as the above-described method for disposing the primer layer 3 on one surface in the thickness direction of the transparent base film 2 .

[0193] As a method for disposing the antifouling layer 5 on one surface in the thickness direction of the antireflection layer 4, a dry coating method is selected from the viewpoint of improving the adhesion between the antifouling layer 5 and the protective film 6. As the dry coating method, a vacuum vapor deposition method is preferably selected.

[0194] In the vacuum deposition method, a deposition source (material of the antifouling layer 5 ) and the antireflection layer 4 are placed facing each other in a vacuum chamber, and the deposition source is heated to evaporate or sublime, so that the evaporated or sublimated deposition source is deposited on the surface of the antireflection layer 4 .

[0195] In the vacuum deposition method, the temperature of the deposition source (crucible) is, for example, 150°C to 300°C, or preferably 180°C to 250°C.

[0196] As a method for disposing the antifouling layer 5 on one surface in the thickness direction of the antireflection layer 4 , a wet coating method is selected from the viewpoint of improving the antifouling durability of the antifouling layer 5 .

[0197] In the wet coating method, first, a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms is dissolved in a known solvent (e.g., toluene) to prepare a solution of the silane compound containing a hydrocarbon group having 6 to 36 carbon atoms. Next, the solution of the silane compound containing a hydrocarbon group having 6 to 36 carbon atoms is applied to one surface in the thickness direction of the antireflection layer 4 and dried as needed.

[0198] As drying conditions, the drying temperature is, for example, 20° C. to 70° C., and preferably 40° C. to 60° C. The drying time is, for example, 5 minutes to 120 minutes, and preferably 8 minutes to 30 minutes.

[0199] Thus, the antifouling layer 5 is arranged on one surface of the antireflection layer 4 in the thickness direction.

[0200] [Fifth step]

[0201] In the fifth step, Figure 2 As shown in FIG2E , the protective film 6 is disposed on one surface in the thickness direction of the antifouling layer 5. Specifically, the protective film 6 is attached to one surface in the thickness direction of the antifouling layer 5.

[0202] Thus, the protective film 6 is disposed on one surface in the thickness direction of the antifouling layer 5. The antireflection film 1 is manufactured in the above manner.

[0203] Effects

[0204] In the antireflection film 1, the antifouling layer 5 contains a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms. The antifouling layer 5 has a water contact angle of 100° or greater, and the peeling force of the protective film 6 exceeds 0.060 N / 50 mm. Consequently, the antifouling layer 5 exhibits excellent adhesion to the protective film 6 and excellent antifouling durability.

[0205] Specifically, from the perspective of protecting the surface of the antireflection film, studies have been conducted to dispose a protective film 6 on the surface of the antireflection film (the surface of the antifouling layer 5 in the antireflection film). In such a case, it is required to improve the adhesion between the antireflection film (antifouling layer 5) and the protective film 6.

[0206] On the other hand, from the perspective of improving the aforementioned adhesion, studies have been conducted to increase the surface free energy (specifically, the dispersion force of the surface free energy) of the antifouling layer 5. However, increasing the surface free energy (specifically, the dispersion force of the surface free energy) of the antifouling layer 5 tends to reduce the antifouling durability of the antifouling layer 5. In other words, the aforementioned adhesion and antifouling durability have an inverse relationship (a trade-off relationship).

[0207] In contrast, in the antireflection film 1, the antifouling layer 5 contains a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms, the water contact angle of the antifouling layer 5 is 100° or greater, and the peeling force of the protective film 6 exceeds 0.060 N / 50 mm. This adjusts the surface free energy of the antifouling layer 5 (specifically, the dispersion of the surface free energy). As a result, both the adhesion between the antifouling layer 5 and the protective film 6 and the antifouling durability of the antifouling layer 5 can be achieved.

[0208] Modifications

[0209] In the modified examples, the same components and processes as those in the first embodiment are marked with the same reference numerals, and their detailed descriptions are omitted. In addition, unless otherwise specified, the modified examples can exert the same effects as those in the first embodiment. Furthermore, the first embodiment and its modified examples can be appropriately combined.

[0210] In one embodiment, the transparent base film 2 includes the transparent resin film 21 and the cured resin layer 22 , but the transparent base film 2 may not include the cured resin layer 22 . In this case, the transparent base film 2 is composed of the transparent resin film 21 .

[0211] In one embodiment, the anti-reflection layer 4 includes two high-refractive index layers and two low-refractive index layers, but the number of high-refractive index layers and low-refractive index layers is not limited.

[0212] [Example]

[0213] The following examples and comparative examples are shown to further specifically describe the present invention. It should be noted that the present invention is not limited to any examples and comparative examples. In addition, the specific numerical values ​​such as the mixing ratio (containing ratio), physical property values, and parameters used in the following description can be replaced by the upper limit value (by the numerical value defined as "below", "less than", or the lower limit value (by the numerical value defined as "above", "exceeding", or the like) of the corresponding recordings of the mixing ratio (containing ratio), physical property values, and parameters described in the above-mentioned "Specific Embodiments".

[0214] <Manufacturing of protective films>

[0215] Production Example 1

[0216] (Preparation of Adhesive Composition)

[0217] In a reaction vessel equipped with a thermometer, a stirrer, a cooler, and a nitrogen inlet tube, 96 parts by mass of 2-ethylhexyl acrylate and 4 parts by mass of 2-hydroxyethyl acrylate as monomer components, 0.2 parts by mass of 2,2'-azobisisobutyronitrile as a polymerization initiator, and 150 parts by mass of ethyl acetate were added. The contents of the vessel were maintained at 23°C and nitrogen was introduced while stirring to perform nitrogen substitution. A polymerization reaction was then carried out for 6 hours while maintaining the temperature of the vessel contents at 65°C, yielding an acrylic polymer solution (solids concentration: 40% by mass). To 250 parts by mass of the resulting acrylic polymer solution (100 parts by mass of the polymer), 73 parts by mass of toluene and 10 parts by mass of acetylacetone were added to dilute the solution to a concentration of 30% by mass. To this solution, 1.3 parts by mass (1.0 part by mass based on solid content) of a 75% by mass solution of a toluene diisocyanate trimer adduct of trimethylolpropane in ethyl acetate ("CORONATE L" manufactured by Tosoh Corporation) as a crosslinking agent was added. Furthermore, 4 parts by mass (0.02 part by mass based on solid content) of a 0.5% by mass solution of dioctyltin dilaurate ("EMBILIZER OL-1" manufactured by Tokyo Fine Chemical Co., Ltd.) as a crosslinking catalyst were added and stirred to produce an adhesive composition. The molar equivalent of the isocyanate groups of the crosslinking agent in the adhesive composition was 0.69 times the molar equivalent of the hydroxyl groups of the polymer.

[0218] The adhesive composition was applied to an antistatically treated 38 μm thick PET film ("Diafoil T100G38" manufactured by Mitsubishi Chemical Co., Ltd.) and dried at 130° C. for 2 minutes to form a 25 μm thick adhesive layer.

[0219] <Manufacturing of anti-reflective film>

[0220] Example 1

[0221] [First process]

[0222] A photopolymerization initiator ("Omnirad907" manufactured by IGM Resins) and a leveling agent ("GRANDIC PC4100" manufactured by DIC) were mixed with a butyl acetate solution of an ultraviolet-curable urethane acrylate ("LUXYDIR17-806" manufactured by DIC Corporation, solid content concentration: 80% by weight). The amounts of the photopolymerization initiator and the leveling agent were set to 2.4 parts by mass and 0.1 parts by mass, respectively, relative to 100 parts by mass of the solid content in the butyl acetate solution of the ultraviolet-curable urethane acrylate. Thus, a curable resin composition was obtained. Next, the curable resin composition was diluted with a mixed solvent of 1-methoxy-2-propanol and cyclopentanone (mass ratio 65 / 35) to obtain a diluted solution of the curable resin composition (solid content concentration 36% by mass).

[0223] Next, a diluted curable resin composition was applied to one side of the thickness direction of a TAC film ("KC8UA" manufactured by Konica Minolta, thickness: 80 μm) as a transparent resin film using a Comma Coater (registered trademark) and dried by heating at 80°C for 60 seconds. Thereafter, the curable resin composition was cured by irradiation with ultraviolet light. During ultraviolet irradiation, a high-pressure mercury lamp was used as the light source, ultraviolet light with a wavelength of 365 nm was used, and the accumulated light intensity was set to 300 mJ / cm 2 Thus, a transparent base film including a TAC film and a cured resin layer (hard coat layer, thickness 6 μm) was prepared.

[0224] [Second step]

[0225] The primer layer is disposed on one surface in the thickness direction of the transparent base film.

[0226] Specifically, the transparent base film was introduced into a roll-to-roll sputtering film forming apparatus, and the pressure in the film forming chamber was reduced to 1×10 －4 Pa. Next, while the transparent base film was being conveyed, a plasma treatment was performed on one surface in the thickness direction of the transparent base film. The plasma treatment conditions were argon gas as an inert gas, a vacuum atmosphere of 0.5 Pa, and a discharge power of 0.15 kW.

[0227] Next, a primer layer (ITO layer, thickness 4 nm) was placed on one surface in the thickness direction of the transparent base material film by sputtering under the following conditions.

[0228] {condition}

[0229] Sputtering gas: argon and oxygen (100:10, volume ratio).

[0230] Target: ITO target (ITO target containing indium oxide and tin oxide at a mass ratio of 90:10).

[0231] Gas pressure during sputtering: 0.2Pa.

[0232] Discharge power: 4.3kW.

[0233] Film forming temperature: -8℃.

[0234] Power supply: MFAC power supply.

[0235] [Third Process]

[0236] Based on the following conditions, an anti-reflection layer (a first high refractive index layer (Nb2O5 layer (thickness 16nm)), a first low refractive index layer (SiO2 layer (thickness 19nm)), a second high refractive index layer (Nb2O5 layer (thickness 102nm)), and a second low refractive index layer (SiO2 layer (thickness 71nm)) were arranged on one side of the thickness direction of the primer layer by sputtering.

[0237] {Conditions for Forming the First High Refractive Index Layer}

[0238] Target: Nb target.

[0239] Sputtering gas: argon and oxygen (100:5, volume ratio).

[0240] Gas pressure during sputtering: 0.5Pa.

[0241] Discharge power: 13kW.

[0242] Film forming temperature: -8℃.

[0243] Power supply: MFAC power supply.

[0244] {Conditions for Forming the First Low-Refractive-Index Layer}

[0245] Target: Si target.

[0246] Sputtering gas: argon and oxygen (100:30, volume ratio).

[0247] Gas pressure during sputtering: 0.2Pa.

[0248] Discharge power: 25kW.

[0249] Film forming temperature: -8℃.

[0250] Power supply: MFAC power supply.

[0251] {Conditions for Forming the Second High Refractive Index Layer}

[0252] Target: Nb target.

[0253] Sputtering gas: argon and oxygen (100:5, volume ratio).

[0254] Gas pressure during sputtering: 0.5Pa.

[0255] Discharge power: 13kW.

[0256] Film forming temperature: -8℃.

[0257] {Conditions for Forming the Second Low-Refractive-Index Layer}

[0258] Target: Si target.

[0259] Sputtering gas: argon and oxygen (100:30, volume ratio).

[0260] Gas pressure during sputtering: 0.2Pa.

[0261] Discharge power: 25kW.

[0262] Film forming temperature: -8℃.

[0263] Power supply: MFAC power supply.

[0264] [Fourth Process]

[0265] An antifouling layer was applied to one side of the antireflection layer in the thickness direction by wet coating. Specifically, octadecyltrimethoxysilane (a formulation containing octadecyltrimethoxysilane and its hydrolyzate, manufactured by Uni-Chem under the trade name "SAMLAY") was first diluted with toluene to prepare an octadecyltrimethoxysilane solution (solids concentration 0.1% by mass). Next, the octadecyltrimethoxysilane solution was applied to one side of the antireflection layer in the thickness direction using a wire bar and dried at 60°C for 10 minutes. This resulted in an antifouling layer (5 nm thick) applied to one side of the antireflection layer in the thickness direction.

[0266] [Fifth step]

[0267] The protective film of Production Example 1 was attached to one surface of the antifouling layer in the thickness direction as a protective film.

[0268] Example 2

[0269] An antireflection film was produced according to the same procedure as in Example 1. In the first step, a diluted curable resin composition prepared according to the following procedure was used.

[0270] (Preparation of a dilution solution of a curable resin composition)

[0271] Nanosilica particles (average primary particle size: 40 nm) were mixed with 67 parts by mass of a curable acrylic resin solution (solids concentration: 50% by mass, nanosilica particle ratio in the solids: 60%), and 33 parts by mass of a multifunctional acrylate to obtain a mixture. Subsequently, 2.0 parts by mass of cross-linked polymethyl methacrylate (PMMA) particles ("Tec-Polymer SSX-103" manufactured by Sekisui Chemical Co., Ltd., average particle size: 3.0 μm, refractive index 1.50) were mixed with 100 parts by mass of this mixture, along with 1.5 parts by mass of an organic montmorillonite ("SUMECTON SAN" manufactured by Kunimine Industries) as a thixotropic agent, 3 parts by mass of a photopolymerization initiator ("OMNIRAD 907" manufactured by IGM Resins), and 0.15 parts by mass of a leveling agent ("Polyflow LE303" manufactured by Kyoeisha Chemical Co., Ltd., a silicone-based leveling agent). This yielded a curable resin composition. Next, the mixture was diluted with a mixed solvent of toluene and cyclopentanone (toluene:cyclopentanone=70:30, mass ratio) to obtain a diluted liquid of the curable resin composition (solid content concentration: 45% by mass).

[0272] Example 3

[0273] An antireflection film was produced according to the same procedure as in Example 1. However, the fourth step was changed as follows.

[0274] [Fourth Process]

[0275] An antifouling layer (thickness: 5 nm) was deposited on one side of the antireflection layer in the thickness direction by dry coating (vacuum deposition). Octadecyltrimethoxysilane (manufactured by TCI) was used as the deposition source. The temperature of the deposition source was set at 200°C.

[0276] Comparative Example 1

[0277] An antireflection film was produced according to the same procedure as in Example 1. However, the fourth step was changed as follows.

[0278] [Fourth Process]

[0279] An antifouling layer (thickness: 5 nm) was applied to one side of the antireflection layer in its thickness direction by dry coating (vacuum deposition). The deposition source used was a coating agent cured from an alkoxysilane compound containing a perfluoropolyether skeleton ("SHIN-ETSU SUBELYN KY1903-1" manufactured by Shin-Etsu Chemical Co., Ltd.). The deposition source temperature was set at 260°C.

[0280] Comparative Example 2

[0281] An antireflection film was produced according to the same procedure as in Example 1. However, the fourth step was changed as follows.

[0282] [Fourth Process]

[0283] An antifouling layer was applied to one side of the antireflection layer in the thickness direction by wet coating. Specifically, a solution containing a fluororesin solution containing perfluoropolyether (Optool UD509, manufactured by Daikin Industries, Ltd.) was applied to one side of the antireflection layer in the thickness direction and dried at 60°C for 10 minutes. This resulted in an antifouling layer (5 nm thick) applied to one side of the antireflection layer in the thickness direction.

[0284] Comparative Example 3

[0285] An antireflection film was produced according to the same procedure as in Example 1. However, the fourth step was changed as follows.

[0286] [Fourth Process]

[0287] An antifouling layer was applied to one side of the antireflection layer in the thickness direction by wet coating. Specifically, octadecyltrimethoxysilane (non-hydrolyzed, manufactured by TCI) was diluted with isopropyl alcohol to prepare an octadecyltrimethoxysilane solution (solids concentration 0.1% by mass). This solution was then applied to one side of the antireflection layer in the thickness direction using a wire bar and dried at 80°C for 1 minute. This resulted in an antifouling layer (5 nm thick) applied to one side of the antireflection layer in the thickness direction.

[0288] <Evaluation>

[0289] (Peel strength of protective film)

[0290] The peel strength of the protective film was measured for each example and comparative example. Specifically, the protective film, cut to a 25 mm width and with the separator removed, was applied with its adhesive layer side to the antifouling layer of a glass plate with an antireflection film using a 2 kg roller. The film was then left at 23°C and 50% RH for 20 minutes. The film was peeled off at a peel angle of 180 degrees and a peel rate of 0.3 m / min. The peel strength of the protective film was measured. The glass plate with the antireflection film was formed by bonding the substrate surface opposite the antireflection layer to a glass plate (manufactured by Matsunami Glass Industries, Ltd., trade name: MICRO SLIDE GLASS S) via an adhesive. The results are shown in Table 1.

[0291] (Water contact angle and antifouling durability of antifouling layer)

[0292] For each Example and Comparative Example, a laminate was prepared after the fourth step and before the fifth step. Next, the contact angle of the antifouling layer of the laminate with respect to pure water (hereinafter sometimes referred to as the initial contact angle) was measured using DMo-501 manufactured by Kyowa Interface Science Co., Ltd. under the following conditions. The results are shown in Table 1.

[0293] {Measurement Conditions}

[0294] Droplet volume: 2μl.

[0295] Temperature: 25℃.

[0296] Humidity: 40%.

[0297] Then, about the antifouling layer of the duplexer of each embodiment and each comparative example, after having implemented the erasing rubber sliding test based on following condition, after cleaning with the cloth that is impregnated with ethanol, measured near the water contact angle of sliding distance 10mm.Measured the water contact angle (sometimes being called the contact angle after the erasing rubber sliding test) by the step identical with above-mentioned method.The results are shown in Table 1.

[0298] {Eraser Slide Test}

[0299] Eraser (Φ6 mm) manufactured by Minoan Co.

[0300] Sliding distance: 15mm.

[0301] Sliding speed: 30 mm / s.

[0302] Load: 500g / 6mmΦ.

[0303] Number of slides: 3000 times.

[0304] Then, the antifouling durability was evaluated based on the following criteria. The results are shown in Table 1.

[0305] ○: The contact angle after the eraser sliding test is 60° or more.

[0306] ×: The contact angle after the eraser sliding test is less than 60°.

[0307] (Surface free energy)

[0308] For each Example and Comparative Example, a laminate was prepared after the fourth step and before the fifth step. The contact angles of the antifouling layer of this laminate were measured for water, diiodomethane, and bromonaphthalene, and the surface free energy was calculated using the Kitazaki-Hata method. The results are shown in Table 1. The contact angle measurement method is the same as that for water contact angle described above.

[0309] (Adhesion)

[0310] The adhesion between the antifouling layer and the protective film of each example and comparative example was evaluated. Specifically, the substrate surface of the antireflection film with a protective film, opposite the antireflection layer, was bonded to a glass plate using an acrylic adhesive. The film was then autoclaved for 15 minutes at a temperature of 50°C and a pressure of 0.5 MPa. Adhesion was then evaluated based on the following criteria. The results are shown in Table 1.

[0311] {Benchmark}

[0312] ○: No warping occurred when the protective film was attached.

[0313] ×: Warping occurred when the protective film was attached.

[0314] [Table 1]

[0315]

[0316] It should be noted that the above invention is provided as an exemplary embodiment of the present invention, but it is only an example and should not be interpreted as limiting. Modifications of the present invention that are not doubtful to those skilled in the art are also included in the scope of the claims.

[0317] Industrial applicability

[0318] The antireflection film of the present invention is preferably used in the production of liquid crystal displays, for example.

Claims

1. An antireflection film comprising, in order toward one side in a thickness direction, a transparent base film, an antireflection layer, an antifouling layer, and a protective film, The antifouling layer contains a silane compound containing a hydrocarbon group having 6 to 36 carbon atoms. The water contact angle of the antifouling layer is greater than 100°. The peeling force of the protective film exceeds 0.060 N / 50 mm.

2. The antireflection film according to claim 1, wherein The dispersion force of the surface free energy of the antifouling layer is greater than 15.5 and less than 32.

4.

3. The antireflection film according to claim 1, wherein The transparent base film includes a transparent resin film and a cured resin layer disposed on one side in the thickness direction of the transparent resin film.

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

5. The antireflection film according to claim 1, wherein The anti-reflection layer comprises a high refractive index layer and a low refractive index layer, The high refractive index layer is a niobium oxide layer, The low refractive index layer is a silicon dioxide layer.

Images