CN119604786A

CN119604786A - Anti-reflective film

Info

Publication number: CN119604786A
Application number: CN202480003258.9A
Authority: CN
Inventors: 宫本幸大; 长命翔太; 中岛一裕
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2023-07-11
Filing date: 2024-07-09
Publication date: 2025-03-11
Also published as: WO2025013861A1

Abstract

The antireflection film (X) of the present invention comprises a substrate film (10), a bonding layer (21) on the substrate film (10), and an antireflection layer (22) on the bonding layer (21). In the antireflection film (X), the total reflectance of the irradiation light of wavelength 380nm to 780nm from the standard light source D65 on the antireflection layer (22) side is 0.40% or less. In the antireflection film (X), the peeling rate of the antireflection layer (22) in a specified second test after the specified first test is less than 20%.

Description

Antireflection film

Technical Field

The present invention relates to an antireflection film.

Background

An antireflection film disposed on the outer surface of a display screen of a display device such as a liquid crystal display or an organic Electroluminescence (EL) display is known. Reflection of outdoor light and image inversion on the display screen are suppressed (antireflection) by the antireflection film. The antireflection film includes, for example, an antireflection layer made of an inorganic oxide and a resin base film for supporting the antireflection layer. Such an antireflection film is described in, for example, patent document 1 below.

Prior art literature

Patent literature

Patent document 1 Japanese patent application laid-open No. 2022-65437

Disclosure of Invention

Problems to be solved by the invention

The antireflection film described in patent document 1 includes a base film, an adhesive layer, and an antireflection layer in this order in the thickness direction. The base film has a Hard Coat (HC) layer on the adhesion layer side. The HC layer contains silica particles. Thus, the HC layer has surface irregularities on the adhesion layer side. The adhesion of the anti-reflection layer to the base film is improved by the anchor effect (anchor effect) generated by the surface roughness of the HC layer and the physicochemical effect of the adhesion layer. When the adhesion of the antireflection layer to the base film is insufficient, the antireflection layer is peeled off from the base film.

However, in the antireflection film of patent document 1, the surface of the antireflection layer (the surface on the opposite side to the base film) also has surface irregularities that follow the surface irregularities of the HC layer. The surface irregularities of the anti-reflection layer scatter a part of light incident on the anti-reflection film. The silica particles in the HC layer also scatter a portion of the light incident on the anti-reflective film. As for the antireflection film, the more the scattering of incident light, the lower the antireflection property.

The invention provides an antireflection film which can continuously obtain a good reflection inhibition effect.

Solution for solving the problem

The invention includes [1] an antireflection film comprising a base film, an adhesion layer on the base film, and an antireflection layer on the adhesion layer, wherein the total reflectance of the antireflection layer side by irradiation light having a wavelength of 380nm to 780nm from a standard light source D65 is 0.40% or less, and the peeling rate of the antireflection layer in the second test after the first test is less than 20%.

First, the substrate film side of the antireflection film was fixed to a glass plate. Then, the antireflection layer of the antireflection film on the glass plate was irradiated with light at a temperature of 85 ℃, a relative humidity of 45%, and an irradiation intensity (integrated illuminance of 290nm to 450 nm) of 150mW/cm ² for 32.5 hours.

In the second test, first, 11 parallel first cuts (2 mm intervals) extending straight in a first direction and 11 parallel second cuts (2 mm intervals) extending straight in a second direction orthogonal to the first direction were formed in the antireflection layer and the sealing layer in the antireflection film on the glass plate by a dicing blade, and 100 squares were formed from the first cuts and the second cuts. Next, isopropyl alcohol was continuously dropped at 2 mL/min to the 100-square area of the antireflection film, while a polyester wiper (wiper) was slid on the 100-square area under conditions of 20mm×20mm wiper contact surface, 1.5kg/20mm ≡c, 50 mm/sec sliding speed, and 1000 reciprocations. Next, the number of peeled off tiles of 1mm ² or more out of the 100 tiles was counted. Next, the peeling rate (%) was calculated by dividing the count value by 100.

The invention includes [2] the antireflection film according to [1], wherein the difference between the total reflectance and the regular reflectance of the antireflection layer side by irradiation light having a wavelength of 450nm is 0.25% or less.

The invention includes [3] the antireflection film according to [1] or [2], wherein the surface of the antireflection layer on the opposite side from the base film has a surface roughness Sa of 4.5nm or less.

The invention includes [4] the antireflection film according to any one of [1] to [3], wherein the developed area ratio Sdr of the surface of the antireflection layer on the opposite side from the base film is 3.0% or less.

The invention includes [5] the antireflection film according to any one of [1] to [4], wherein a difference between a maximum peak height Sp and a maximum valley depth Sv of a surface of the antireflection layer on an opposite side from the base film is 30nm or less.

The invention includes [6] the antireflection film according to any one of [1] to [5], wherein the root mean square slope Sdq of the surface of the antireflection layer on the opposite side from the base film is 12 or less.

The invention includes [7] the antireflection film according to any one of [1] to [6] above, wherein the surface roughness Sa of the surface of the base film on the antireflection layer side is 1.0nm or more and 4.0nm or less.

The invention includes [8] the antireflection film according to any one of [1] to [7], wherein the developed area ratio Sdr of the surface of the base film on the antireflection layer side is 2.0% or more and 10% or less.

The invention includes [9] the antireflection film according to any one of [1] to [8], wherein a difference between a maximum peak height Sp and a maximum valley depth Sv of a surface of the base film on the antireflection layer side is 10nm or more and 50nm or less.

The invention includes [10] the antireflection film according to any one of [1] to [9], wherein the root mean square slope Sdq of the surface of the base film on the antireflection layer side is 12 or more and 30 or less.

Effects of the invention

As described above, in the antireflection film of the present invention, the total reflectance of the antireflection layer side by the irradiation light having a wavelength of 380nm to 780nm from the standard light source D65 is 0.40% or less, and the peeling rate of the antireflection layer in the second test after the first test (the accelerated weather resistance test) is less than 20%. The total reflectance of the antireflection film is 0.40% or less, whereby scattering of light incident on the film is reduced, and antireflection property of the antireflection film can be ensured. The above-mentioned peeling rate of the antireflection layer is less than 20%, whereby the reduction of the antireflection property of the antireflection film due to peeling of the antireflection layer can be suppressed in practical use of the antireflection film.

Therefore, according to the antireflection film of the present invention, a good reflection suppressing effect can be continuously obtained.

Drawings

FIG. 1 is a schematic cross-sectional view of one embodiment of an anti-reflective film of the present invention.

Fig. 2A to 2C show an example of a method for manufacturing the antireflection film shown in fig. 1. Fig. 2A shows a cured resin layer forming step, fig. 2B shows an adhesion layer forming step, and fig. 2C shows an antireflection layer forming step.

Fig. 3 is a schematic configuration diagram of an apparatus for performing a plasma treatment step and a film formation step in an example of the method for manufacturing an antireflection film shown in fig. 1.

Fig. 4 is a perspective view showing a positional relationship between a low inductance antenna and a substrate film in the plasma processing chamber shown in fig. 3.

Fig. 5 is a cross-sectional view showing a positional relationship between a low inductance antenna and a substrate film in the plasma processing chamber shown in fig. 3.

Detailed Description

The antireflection film X according to an embodiment of the present invention includes, in order in the thickness direction H, a base film 10, an adhesion layer 21, and an antireflection layer 22. The antireflection film X spreads in a direction (in-plane direction D) orthogonal to the thickness direction H. The antireflection film X is disposed on an outer surface of a display screen in a display device, for example. Specifically, the substrate film 10 side of the antireflection film X is bonded to the outer surface of the display device via a bonding material such as a transparent adhesive sheet. Examples of the display device include a liquid crystal display and an organic EL display. In such an antireflection film X, the antireflection layer 22 has a surface 22A on the side opposite to the base film 10.

In the present embodiment, the base film 10 includes a resin film 11 and a cured resin layer 12 in this order in the thickness direction H. In the present embodiment, the resin film 11 is in contact with the cured resin layer 12.

In the base film 10, the cured resin layer 12 forms a first surface 10a, and the resin film 11 forms a second surface 10b.

The resin film 11 is a factor for securing the strength of the antireflection film X. The resin film 11 is, for example, a transparent resin film having flexibility. Examples of the material of the resin film 11 include polyester resins, polyolefin resins, cellulose resins, acrylic resins, polycarbonate resins, polyethersulfone resins, polyarylate resins, melamine resins, polyamide resins, polyimide resins, and polystyrene resins. Examples of the polyester resin include polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate. Examples of the polyolefin resin include polyethylene, polypropylene, and cycloolefin polymer (COP). As the cellulose resin, for example, cellulose Triacetate (TAC) is cited. These materials may be used alone or in combination of two or more. From the viewpoints of transparency and strength, the material of the resin film 11 is preferably at least one selected from the group consisting of polyester resins, polyolefin resins, and cellulose resins, and more preferably at least one selected from the group consisting of PET, COP, and TAC.

The thickness of the resin film 11 is preferably 10 μm or more, more preferably 20 μm or more, further preferably 30 μm or more, and further preferably 200 μm or less, more preferably 150 μm or less, further preferably 100 μm or less. When the thickness of the resin film 11 is equal to or greater than the lower limit, the strength of the antireflection film X can be ensured. When the thickness of the resin film 11 is equal to or less than the upper limit, the handling properties of the base film 10 in the process described later of the roll-to-roll system can be ensured.

The total light transmittance (JIS K7375:2008) of the resin film 11 is preferably 80% or more, more preferably 90% or more, still more preferably 95% or more, and further, for example, 100% or less. When the total light transmittance of the resin film 11 is equal to or higher than the lower limit, good transparency can be ensured in the antireflection film X.

The cured resin layer 12 is a functional layer containing a resin. Specifically, the curable resin layer 12 is a cured product of a curable resin composition containing a curable resin. Examples of the functional layer include a hard coat layer. The hard coat layer is a layer that makes it difficult to form scratches on the exposed surface (upper surface in fig. 1) of the antireflection layer 22.

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

Examples of the curable resin include ultraviolet curable resins and thermosetting resins. The curable resin is preferably an ultraviolet curable resin. In the case where the curable resin is an ultraviolet curable resin, the curable resin can be cured without heating at a high temperature, and therefore, the manufacturing efficiency of the antireflection film X can be improved.

The curable resin may contain a reactive diluent described in, for example, japanese patent application laid-open No. 2008-88309. Specifically, the resin may contain a multifunctional (meth) acrylate.

When the base film 10 has the cured resin layer 12, it is preferable that inorganic oxide particles contained in the cured resin layer 12 are small. The smaller the inorganic oxide particles in the cured resin layer 12, the more the scattering of light incident on the antireflection film X due to the particles in the base film 10 can be suppressed, and the manufacturing cost of the antireflection film X can be reduced. Examples of the material of 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 mass% or less, more preferably 10 mass% or less, further preferably 5 mass% or less, further preferably 1 mass% or less, further preferably 0.5 mass% or less, further preferably 0.2 mass% or less, further preferably 0.1 mass% or less, and particularly preferably 0.0 mass%.

The thickness of the cured resin layer 12 is preferably 1 μm or more, more preferably 3 μm or more, further preferably 5 μm or more, and further preferably 30 μm or less, more preferably 25 μm or less, further preferably 20 μm or less. When the thickness of the cured resin layer 12 is equal to or greater than the lower limit, the function of the cured resin layer 12 can be ensured. Specifically, in the case where the cured resin layer 12 is a hard coat layer, scratch resistance of the antireflection layer 22 can be ensured. When the thickness of the cured resin layer 12 is equal to or less than the upper limit, cracking of the cured resin layer 12 can be suppressed, and good conveyability can be ensured in the roll-to-roll process.

The total light transmittance (JIS K7375:2008) of the base film 10 is preferably 80% or more, more preferably 90% or more, still more preferably 95% or more, and further, for example, 100% or less. When the total light transmittance of the base film 10 is equal to or higher than the lower limit, good transparency can be ensured in the antireflection film X.

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 1.0nm or more, more preferably 1.2nm or more, further preferably 1.3nm or more, further preferably 1.5nm or more, further preferably 1.7nm or more, further preferably 4.0nm or less, further preferably 3.0nm or less, further preferably 2.5nm or less, further preferably 2.0nm or less. When the surface roughness Sa of the first surface 10a is equal to or greater than the lower limit value, the adhesion of the antireflection layer 22 to the base film 10 via the adhesion layer 21 is improved by the adhesion effect of the fine irregularities of the first surface 10a to the adhesion layer 21. The surface roughness Sa of the first surface 10a is equal to or less than the upper limit value, and is suitable for suppressing the reduction of the scratch resistance of the surface 22A of the antireflection layer 22. The method for measuring the surface roughness Sa is as described in examples mentioned later (the same applies to the method for measuring other parameters regarding the surface properties described later based on ISO 25178-2:2012).

The developed area ratio Sdr of the first surface 10a (based on ISO 25178-2:2012) is preferably 2.0% or more, more preferably 3.0% or more, further preferably 4.0% or more, further preferably 5.0% or more, further preferably 6.0% or more, further preferably 7.0% or more, further preferably 10% or less, further preferably 8.0% or less, further preferably 7.5% or less. The expansion area ratio Sdr represents the ratio of the actual surface area of the surface having the concave-convex shape in the predetermined area to the virtual area when the area is assumed to be flat. When the expansion area ratio Sdr of the first surface 10a is equal to or greater than the lower limit value, the adhesion of the antireflection layer 22 to the base film 10 via the adhesion layer 21 is improved by the adhesion effect of the fine irregularities of the first surface 10a to the adhesion layer 21. The spread area ratio Sdr of the first surface 10a is equal to or smaller than the upper limit value, and is suitable for suppressing the deterioration of the scratch resistance of the surface 22A of the antireflection layer 22.

The difference (Sp-Sv) between the maximum peak height Sp (based on ISO 25178-2:2012) and the maximum valley depth Sv (based on ISO 25178-2:2012) of the first surface 10a is preferably 10nm or more, more preferably 12nm or more, further preferably 13nm or more, more preferably 15nm or more, still more preferably 20nm or more, further preferably 50nm or less, more preferably 42nm or less, still more preferably 40nm or less, still more preferably 30nm or less, still more preferably 25nm or less. When the difference (Sp-Sv) between the first surfaces 10a is equal to or greater than the lower limit, the adhesion of the antireflection layer 22 to the base film 10 via the adhesion layer 21 is improved by the adhesion effect of the fine irregularities of the first surfaces 10a to the adhesion layer 21. The difference (Sp-Sv) between the first surfaces 10a is equal to or less than the upper limit value, and is suitable for suppressing the deterioration of the scratch resistance of the surface 22A of the antireflection layer 22.

The root mean square slope Sdq of the first surface 10a (based on ISO 25178-2:2012) is preferably 12 or more, more preferably 14 or more, further preferably 16 or more, further preferably 18 or more, further preferably 20 or more, further preferably 30 or less, further preferably 25 or less, further preferably 22 or less. The root mean square slope Sdq is a parameter calculated from the root mean square of the slopes at all points of the prescribed region. When the root mean square slope Sdq of the first surface 10a is equal to or greater than the lower limit, the adhesion of the antireflection layer 22 to the base film 10 via the adhesion layer 21 is improved by the adhesion effect of the fine irregularities of the first surface 10a to the adhesion layer 21. The root mean square slope Sdq of the first surface 10a is equal to or less than the upper limit value, and is suitable for suppressing the deterioration of the scratch resistance of the surface 22A of the antireflection layer 22.

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

The adhesive layer 21 is disposed on one surface of the base film 10 in the thickness direction H. Specifically, the sealing layer 21 is disposed on the first surface 10a of the base film 10. The sealing layer 21 is in contact with the base film 10. The adhesion layer 21 is a layer for improving adhesion of the antireflection layer 22 to the base film 10. Examples of the material of 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. In view of both adhesion to the base film 10 and the antireflective layer 22 and transparency of the adhesion layer 21, indium tin composite oxide (ITO) or silicon oxide (SiOx) is preferable as the material of the adhesion layer 21. The silicon oxide used as the material of the adhesion layer 21 is preferably SiOx having an oxygen content smaller than the stoichiometric composition, and more preferably SiOx having x of 1.2 or more and 1.95 or less.

The thickness of the adhesion layer 21 is preferably 1nm or more, more preferably 2nm or more, further preferably 3nm or more, and further preferably 10nm or less, more preferably 7nm or less, further preferably 5nm or less. When the thickness of the adhesion layer 21 is equal to or greater than the lower limit, adhesion between the base film 10 and the antireflection layer 22 can be ensured. When the thickness of the adhesion layer 21 is equal to or less than the upper limit, the transparency of the adhesion layer 21 can be ensured.

The antireflection layer 22 is disposed on one surface of the adhesion layer 21 in the thickness direction H. The anti-reflection layer 22 is connected to the adhesion layer 21. The antireflection layer 22 is a layer (antireflection) that suppresses the reflection intensity of outdoor light.

In the present embodiment, the antireflection layer 22 includes, in order from the adhesion layer 21 side in the thickness direction H, a high refractive index layer 22a, a low refractive index layer 22b, a high refractive index layer 22c, a low refractive index layer 22d, and an antifouling surface layer 22e. The antireflection layer 22 of the present embodiment is an antireflection layer with an antifouling surface layer. The high refractive index layer 22a is in contact with the sealing layer 21. The high refractive index layer 22a is in contact with the low refractive index layer 22 b. The low refractive index layer 22b is in contact with the high refractive index layer 22 c. The high refractive index layer 22c is in contact with the low refractive index layer 22 d. The high refractive index layers 22a, 22c are relatively large refractive index layers, and the low refractive index layers 22b, 22d are relatively small refractive index layers. In the antireflection layer 22, for example, the reflected light intensity is attenuated by interference between reflected light at a plurality of interfaces of the high refractive index layers 22a, 22c and the low refractive index layers 22b, 22 d. Such interference can be exhibited by adjusting the optical film thickness (product of refractive index and thickness of film) of each layer of the antireflection layer 22.

The high refractive index layer 22a (first high refractive index layer) is formed of a high refractive index material having a refractive index of preferably 1.9 or more at a wavelength of 550 nm. Examples of the high refractive index material include niobium oxide (Nb ₂O₅), titanium oxide, zirconium oxide, indium tin composite oxide (ITO), and antimony tin composite oxide (ATO). From the viewpoint of both high refractive index and low absorptivity of visible light, the high refractive index material is preferably niobium oxide (refractive index 2.33). The optical film thickness of the high refractive index layer 22a is, for example, 20nm or more and, further, 55nm or less.

The low refractive index layer 22b (first low refractive index layer) is formed of a low refractive index material having a refractive index of preferably 1.6 or less at a wavelength of 550 nm. Examples of the low refractive index material include silicon dioxide (SiO ₂) and magnesium fluoride. From the viewpoint of both low refractive index and low absorptivity of visible light, the low refractive index material is preferably silicon dioxide (refractive index 1.46). The optical film thickness of the low refractive index layer 22b is, for example, 15nm or more and, for example, 70nm or less.

The high refractive index layer 22c (second high refractive index layer) is formed of a high refractive index material having a refractive index of preferably 1.9 or more at a wavelength of 550 nm. As the high refractive index material, the materials mentioned above for the high refractive index layer 22a are exemplified, and niobium oxide is preferable. The optical film thickness of the high refractive index layer 22c is, for example, 60nm or more and 330nm or less.

The low refractive index layer 22d (second low refractive index layer) is formed of a low refractive index material having a refractive index of preferably 1.6 or less at a wavelength of 550 nm. As the low refractive index material, the materials mentioned above for the low refractive index layer 22b are cited, and silica is preferable. The optical film thickness of the low refractive index layer 22d is, for example, 100nm or more and 160nm or less.

The total thickness of the antireflection layer 22 from the high refractive index layer 22a to the low refractive index layer 22d is preferably 180nm or more, more preferably 200nm or more, further preferably 220nm or more, further preferably 320nm or less, more preferably 280nm or less, further preferably 250nm or less. When the total thickness of the antireflection layer 22 is equal to or greater than the lower limit, the antireflection layer 22 can ensure a function of attenuating the intensity of reflected light. When the total thickness of the antireflection layer 22 is equal to or less than the upper limit value, cracking of the antireflection layer 22 can be suppressed.

The stain-proofing surface layer 22e is a layer having a stain-proofing function. The stain-proofing surface layer 22e is disposed on the low refractive index layer 22 d. The antifouling function of the antifouling surface layer 22e includes a function of suppressing adhesion of a pollutant such as hand grease to the exposed surface of the film when the antireflection film X is used, and a function of facilitating removal of the adhered pollutant.

Examples of the material of the stain-proofing surface layer 22e include organofluorine compounds. As the organofluorine 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).

R¹－R²－X－(CH₂)_m－Si(OR³)₃(1)

In the general formula (1), R ¹ represents a linear or branched fluorinated alkyl group (having 1 to 20 carbon atoms, for example) 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 in the alkyl group are substituted with fluorine atoms.

R ² represents a structure comprising at least one repeating structure of a perfluoropolyether (PFPE) group, preferably a structure comprising two repeating structures of a PFPE group. Examples of the repeating structure of the PFPE group include a repeating structure of a linear PFPE group and a repeating structure of a branched PFPE group. Examples of the repeating structure of the linear PFPE group include a structure represented by- (OC _nF_2n)_p - (n represents an integer of 1 to 20 inclusive and p represents an integer of 1 to 50 inclusive and the same applies hereinafter)). As the repeating structure of the branched PFPE group, examples thereof include a structure represented by- (OC (CF ₃)₂)_p) -and a structure represented by- (OCF ₂CF(CF₃)CF₂)_p) -as the PFPE-based repeating structure, the repeating structure of the linear PFPE group is preferably exemplified, and- (OCF ₂)_p -and- (OC ₂F₄)_p -are more preferably exemplified.

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

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

M represents an integer of 1 or more. M is preferably an integer of 20 or less, more preferably an integer of 10 or less, and even more preferably an integer of 5 or less.

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

CF₃－(OCF₂)_q－(OC₂F₄)_r－O－(CH₂)₃－Si(OCH₃)₃(2)

In the general formula (2), q represents an integer of 1 to 50 inclusive, and r represents an integer of 1 to 50 inclusive.

The alkoxysilane compound having a perfluoropolyether group may be used alone or in combination of two or more.

In the present embodiment, the stain-proofing surface layer 22e is a film (dry coating film) formed by a dry coating method. Examples of the dry coating method include a sputtering method, a vacuum deposition method, and a Chemical Vapor Deposition (CVD). The stain-proofing surface layer 22e is preferably a dry coating film, more preferably a vacuum deposition film.

In the case where the material of the anti-fouling surface layer 22e contains an alkoxysilane compound having a perfluoropolyether group and the anti-fouling surface layer 22e is a dry coating film (preferably a vacuum deposition film), it is preferable to ensure a high bonding force of the anti-fouling surface layer 22e to the substrate of the anti-fouling surface layer 22e, and thus it is preferable to ensure the peel resistance of the anti-fouling surface layer 22 e. The high peel resistance of the anti-fouling surface layer 22e helps maintain the anti-fouling function of the anti-fouling surface layer 22 e.

The thickness of the stain-proofing surface layer 22e is preferably 1nm or more, more preferably 3nm or more, further preferably 5nm or more, particularly preferably 7nm or more, further preferably 25nm or less, more preferably 20nm or less, further preferably 18nm or less, from the viewpoint of securing the peel resistance of the stain-proofing surface layer 22 e.

The antireflection layer 22 has a surface 22A (surface of the stain-proofing surface layer 22 e) on the opposite side to the base film 10. The surface roughness Sa of the surface 22A (arithmetic mean height based on ISO 25178-2:2012) is preferably 4.5nm or less, more preferably 3.0nm or less, further preferably 2.5nm or less, further preferably 2.0nm or less, still further preferably 1.8nm or less. In the case where the surface roughness Sa of the surface 22A is equal to or less than the above-described upper limit value, light scattering at the surface 22A can be suppressed. The surface roughness Sa of the surface 22A is preferably 1.0nm or more, more preferably 1.3nm or more, further preferably 1.5nm or more, further preferably more than 1.5nm, and further preferably 1.6nm or more. The surface roughness Sa of the surface 22A being equal to or higher than the lower limit value is suitable for reducing the friction force of the surface 22A to ensure good slidability.

The spread area ratio Sdr of the surface 22A is preferably 3.0% or less, more preferably 2.5% or less, and further preferably 2.2% or less. When the spread area ratio Sdr of the surface 22A is equal to or smaller than the upper limit value, light scattering at the surface 22A can be suppressed. The spread area ratio Sdr of the surface 22A is preferably 0.3% or more, more preferably 0.7% or more, further preferably 1.0% or more, further preferably 1.5% or more, and further preferably 2.0% or more. The spread area ratio Sdr of the surface 22A being equal to or larger than the lower limit value is suitable for reducing the friction force of the surface 22A to ensure good slidability.

The difference (Sp-Sv) between the maximum peak height Sp and the maximum valley depth Sv of the surface 22A is preferably 30nm or less, more preferably 20nm or less, and still more preferably 17nm or less. When the difference (Sp-Sv) between the surfaces 22A is equal to or greater than the lower limit value, light scattering at the surfaces 22A can be suppressed. The difference (Sp-Sv) between the maximum peak height Sp and the maximum valley depth Sv of the surface 22A is preferably 5nm or more, more preferably 10nm or more, still more preferably 12nm or more, still more preferably 14nm or more, still more preferably 16nm or more. The difference (Sp-Sv) between the surfaces 22A is equal to or less than the upper limit value, and is suitable for reducing the friction force of the surfaces 22A to ensure good sliding properties.

The root mean square slope Sdq of the surface 22A is preferably 12 or less, more preferably 11.9 or less, and further preferably 11.8 or less. When the root mean square slope Sdq of the surface 22A is equal to or greater than the lower limit value, light scattering at the surface 22A can be suppressed. The root mean square slope Sdq of the surface 22A is preferably 5 or more, more preferably 8 or more, further preferably 10 or more, further preferably 11 or more, further preferably 11.2 or more, and further preferably 11.6 or more. The root mean square slope Sdq of the surface 22A being equal to or less than the upper limit value is suitable for reducing the friction force of the surface 22A to ensure good slidability.

The total reflectance of the antireflection film X on the antireflection layer 22 side of the irradiation light having a wavelength of 380nm to 780nm from the standard light source D65 is 0.40% or less, preferably 0.36% or less, more preferably 0.33% or less, and further, for example, 0.00% or more. When the total reflectance of the antireflection film X is equal to or less than the upper limit value, the antireflection property of the antireflection film X can be ensured. This suppresses reflection of outdoor light and image reflection on a display screen on which the antireflection film X is disposed in the display device. The method of measuring the total reflectance will be described in examples mentioned later.

The difference Δr between the total reflectance and the regular reflectance of the antireflection layer 22 side of the irradiation light of the antireflection film X having a wavelength of 450nm is preferably 0.25% or less, more preferably 0.18% or less, still more preferably 0.16% or less, still more preferably 0.14% or less, and further, for example, 0.01% or more. The difference Δr is equal to or less than the upper limit value, and is suitable for suppressing light scattering at the antireflection film X, and therefore is suitable for reducing the cloudiness of the display screen of the display device provided with the antireflection film X. The method of determining the difference Δr is as described in the examples mentioned hereinafter.

The peeling rate of the antireflection layer 22 in the second test described below of the antireflection film X after the first test described below (the accelerated weather resistance test) is preferably less than 20%, more preferably 15% or less, further preferably 10% or less, still further preferably less than 10%. The methods of the first test and the second test will be described more specifically in examples mentioned later. When the peeling rate of the antireflection layer 22 is equal to or less than the upper limit value, the reduction of the antireflection property of the antireflection film X due to peeling of the antireflection layer 22 can be suppressed in practical use of the antireflection film X.

First, the substrate film 10 side of the antireflection film X was fixed to a glass plate. Then, the antireflection layer 22 of the antireflection film X on the glass plate was irradiated with light at a temperature of 85 ℃, a relative humidity of 45% and an irradiation intensity (integrated illuminance of 290nm to 450 nm) of 150mW/cm ² for 32.5 hours.

In the second test, first, 11 parallel first cuts (2 mm intervals) extending straight in the first direction and 11 parallel second cuts (2 mm intervals) extending straight in the second direction orthogonal to the first direction were formed in the antireflection layer 22 and the sealing layer 21 in the antireflection film X on the glass plate after the first test by a dicing blade, and 100 squares were formed by the first cuts and the second cuts. Next, isopropyl alcohol was continuously dropped at 2 mL/min in the region of 100 squares of the antireflection film X, while the polyester wiper was slid on the region of 100 squares under conditions of wiper contact surface 20mm×20mm, load 1.5kg/20mm ≡, sliding speed 50 mm/sec, and 1000 reciprocation. Next, the number of peeled off tiles of 1mm ² or more out of 100 tiles was counted. Next, the peeling rate (%) was calculated by dividing the count value by 100.

As described above, the total reflectance of the antireflection film X on the side of the antireflection layer 22 by the irradiation light having a wavelength of 380nm to 780nm from the standard light source D65 is 0.40% or less, and the peeling rate of the antireflection layer 22 in the second test after the first test (the accelerated weather resistance test) is less than 20%. By setting the total reflectance of the antireflection film X to 0.40% or less, scattering of light incident on the antireflection film X is reduced, and antireflection performance of the antireflection film X can be ensured. By the above-described peeling rate of the antireflection layer 22 being less than 20%, in practical use of the antireflection film X, the decrease in the antireflection property of the antireflection film X due to peeling of the antireflection layer 22 can be suppressed. Therefore, a good reflection suppressing effect can be continuously obtained according to the antireflection film X.

Fig. 2A to 2C show an example of a method for manufacturing the antireflection film X. The manufacturing method includes a cured resin layer forming step (fig. 2A), a plasma treatment step, and a film forming step (fig. 2B and 2C).

In the cured resin layer forming step, as shown in fig. 2A, a cured resin layer 12 is formed on the long resin film 11. Thus, the base film 10 was obtained. The curable resin layer 12 can be formed by applying the curable resin composition to the resin film 11 to form a coating film, and then curing the coating film. The curable resin composition may contain other components than the curable resin as necessary. Examples of the other components include solvents and leveling agents. Examples of the solvent include butyl acetate, ethyl acetate, toluene and cyclopentanone. When the curable resin composition contains an ultraviolet curable resin as the curable resin, the curable resin composition preferably contains a photopolymerization initiator. When the curable resin composition contains a thermosetting resin as the curable resin, the curable resin composition preferably contains a thermal polymerization initiator.

When the curable resin composition contains a solvent, the coating film on the resin film 11 is dried after the curable resin composition is applied. The drying temperature is, for example, 50 ℃ or higher, and also, for example, 120 ℃ or lower. The drying time is, for example, 10 seconds or more, and is, for example, 10 minutes or less.

When the curable resin composition contains an ultraviolet curable resin, the coating film on the resin film 11 is cured by ultraviolet irradiation. Examples of the light source for irradiation with ultraviolet rays include a high-pressure mercury lamp and an LED lamp. The cumulative irradiation light amount of ultraviolet rays is, for example, 100mJ/cm ² or more, and is, for example, 500mJ/cm ² or less.

When the curable resin composition contains a thermosetting resin, the coating film on the resin film 11 is cured by heating. The heating temperature is, for example, 100 ℃ or more, and 150 ℃ or less. The heating time is, for example, 10 seconds or more, and is, for example, 10 minutes or less.

As described above, the long base film 10 can be produced. In the present embodiment, a roll of the long base film 10 is prepared. Specifically, the base film 10 is wound such that the first surface 10a of the base film 10 faces inward in the roll radial direction.

In the present manufacturing method, next, the substrate film 10 is transported as a work film W in a roll-to-roll manner under a reduced pressure atmosphere, and a plasma treatment process and a film formation process are sequentially performed. The apparatus Y shown in fig. 3 is an example of an apparatus for performing a plasma processing step and a film forming step. The apparatus Y includes a pull-out chamber R1, a winding chamber R2, a connection chamber C1, a plasma processing chamber C2, a connection chamber C3, a film forming chamber C4 (first film forming chamber), a connection chamber C5, and a film forming chamber C6 (second film forming chamber).

The drawing chamber R1 includes a drawing roller 51 for drawing the working film W. A roll of the long base film 10 as the working film W is mounted on the take-out roller 51. A predetermined number of guide rollers G for guiding the work film W are provided in the drawing chamber R1.

The winding chamber R2 includes a winding roller 52 for winding the working film W. A predetermined number of guide rollers G for guiding the working film W are provided in the winding chamber R2.

The connection chamber C1 is disposed after the extraction chamber R1 and before the plasma processing chamber C2 in the traveling direction of the working film W. A predetermined number of guide rollers G for guiding the working film W are provided in the connection chamber C1. The connection chamber C1 is connected to a vacuum pump, not shown, and is configured to be able to adjust the pressure in the chamber. During operation of the apparatus Y, the pressure in the connecting chamber C1 is maintained at a predetermined pressure between the pressure in the pumping chamber R1 and the pressure in the plasma processing chamber C2. Thereby, a pressure difference between the pumping chamber R1 and the plasma processing chamber C2 is ensured.

The plasma processing chamber C2 is disposed between the connection chamber C1 and the connection chamber C3 in the traveling direction of the working film W. In the plasma processing chamber C2, a plasma processing step is performed as described later. A first line L1 with a flow rate control valve for introducing a gas into the plasma processing chamber C2 is connected.

In the present embodiment, the plasma processing chamber C2 includes a plurality of low inductance antennas (LA) 71. The low inductance antenna means 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 the present embodiment, as shown in fig. 4 and 5, LA71 is arranged in the chamber of plasma processing chamber C2 in a state supported by fixture 72 and covered by cover block 73 (omitted in fig. 4) (the case where the number of LA71 is four is exemplarily shown).

The plurality of LA71 are arranged in a row in the traveling direction of the base film 10 and in a direction perpendicular to the traveling direction (the width direction of the base film 10). The fixture 72 is a vacuum flange. As shown in fig. 5, LA71 is fixed to a fixing member 72 via a through hole 74. As shown in fig. 4, the fixture 72 is assembled to an opening 75 provided in a wall portion of the plasma processing chamber C2. Specifically, the holder 72 is assembled in the opening 75 with a sealing member (not shown) interposed between the wall of the plasma processing chamber C2 and the holder 72. LA71 is electrically connected to a high-frequency power supply (rf power supply) via an impedance matching unit outside the plasma processing chamber C2. Such LA71 is formed of a conductor. Examples of the conductor include copper and silver, and copper is preferable. LA71 may also be covered by an insulator. Examples of the insulator include glass and quartz.

The cover block 73 includes a block main body 73A and a plurality of partition plates 73B. The block main body 73A has a plurality of accommodation spaces 73A. Each accommodation space 73a accommodates one LA71 therein. The partition plate 73B is configured to close the accommodation space 73a. The accommodation space 73a is a closed space. In the cover block 73, the block main body 73A is made of aluminum, for example. Examples of the aluminum include aluminum a5052. The partition plate 73B is made of an insulating material. Examples of the insulating material include quartz and glass. The distance d' (shown in fig. 5) between the substrate film 10 and the cover block 73 traveling in the plasma processing chamber C2 is, for example, 50 to 200mm. Such a cover block 73 helps to prevent the LA71 from being damaged and contaminated by the plasma treatment without excessively reducing the plasma conversion efficiency due to the power applied to the LA71, and helps to suppress damage to the plasma-treated substrate film 10.

As shown in fig. 4, in the present embodiment, LA71 has an open loop shape. The LA71 has an open loop shape which is advantageous for reducing the inductance of the LA 71. Therefore, according to the LA71 of the open-loop shape, an increase in voltage due to an increase in power applied to the LA71 can be suppressed. This suppresses abnormal discharge during plasma processing described later. By suppressing abnormal discharge, damage to the substrate film 10 subjected to plasma treatment can be suppressed. Specifically, LA71 has a U-shape with two free ends. For each LA71, both free ends are fixed to the fixing member 72 in such a manner as to be aligned in the width direction of the base film 10.

In the present embodiment, LA71 has extension portions 71a on the opposite sides of the two free ends. The extension 71a extends in parallel with respect to the substrate film 10 passing through the plasma processing chamber C2. The extension 71a extends in the width direction of the base film 10. Each extension 71a may extend in the traveling direction of the base film 10 (four LA71 may be disposed in this way). The length of the extension portion 71a is, for example, 50 to 1150mm (fig. 4 exemplarily illustrates a case where the length of the extension portion 71a is the same as a maximum length d ₂ of LA71 described later). LA71 may also have a coil shape instead of an open loop shape.

LA71 extends from anchor 72 toward substrate film 10. LA71 preferably extends in a direction perpendicular to anchor 72. The length d ₁ of the LA71 extending from the fixing member 72 is, for example, 30 to 150mm. The maximum length d ₂ of the LA71 in the plane direction of the base film 10 is, for example, 50 to 150mm. The distance d ₃ (shown in fig. 5) between LA71 and the base film 10 is, for example, 50 to 200mm. The extension length d ₁ is preferably the same as the separation distance d ₃. The ratio (d ₃/d₁) of the distance d ₃ to the extension length d ₁ is, for example, 0.5 to 3.5. The number (number of columns) of LA71 arranged at intervals in the traveling direction of the substrate film 10 may be 1, 2 or 3, or 4 or more if necessary, depending on the traveling speed (that is, plasma treatment time) of the substrate film 10. The distance d ₄ between adjacent LA71 centers in the traveling direction of the base film 10 is, for example, 100 to 500mm. The distance d ₅ between adjacent LA71 centers in the width direction of the base film 10 is, for example, 200 to 500mm. By adjusting the center-to-center distance d ₅, uniformity of plasma density in the width direction of the substrate film 10, which will be described later, can be controlled. The inter-center distance d ₄ is preferably the same as the inter-center distance d ₅. The ratio (d ₅/d₄) of the inter-center distance d ₅ to the inter-center distance d ₄ is, for example, 0.5 to 2.0. The center points of the extension portions 71a of the four LA's 71 are preferably formed as vertexes to form a square. According to such a group LA71, a high-density plasma can be generated. As LA71, for example, a high-frequency antenna for generating plasma described in japanese patent application laid-open No. 2013-258153 may be used.

In the present embodiment, the plasma processing chamber C2 further includes a conveying roller 53. The conveying roller 53 is a main guide roller for conveying the working film W in the plasma processing chamber C2. The conveying roller 53 has a temperature adjusting function capable of heating or cooling the working film W. That is, the conveying roller 53 is a conveying roller with a temperature adjusting function.

In the operation of the apparatus Y, the transport roller 53 transports the base film 10 while being in contact with the second surface 10b of the base film 10. The LA71 is disposed opposite the conveying roller 53. According to the apparatus Y provided with such a plasma processing chamber C2, in the plasma processing step S2, the substrate film 10 can be subjected to plasma processing while the substrate film 10 is cooled or heated by the conveying roller 53 with a temperature adjusting function in contact with the substrate film 10. By controlling the temperature of the base film 10, thermal deformation of the base film 10 can be suppressed, and also the influence of the thermal deformation on the conveyance of the base film 10 can be suppressed.

The connection chamber C3 is disposed after the plasma processing chamber C2 in the traveling direction of the working film W and before the film forming chamber C4. A predetermined number of guide rollers G for guiding the working film W are provided in the connection chamber C3. The connection chamber C3 is connected to a vacuum pump, not shown, and is configured to be capable of adjusting the pressure in the chamber. During operation of the apparatus Y, the pressure in the connection chamber C3 is maintained at a predetermined pressure between the pressure in the plasma processing chamber C2 and the pressure in the film forming chamber C4. Thereby, a pressure difference between the plasma processing chamber C2 and the film forming chamber C4 is ensured.

The film forming chamber C4 is disposed after the connection chamber C3 in the traveling direction of the working film W. The film forming chamber C4 is connected to a vacuum pump, not shown, and is configured to be able to adjust the chamber to a predetermined vacuum level. In the film forming chamber C4, a film forming process from the high refractive index layer 22a to the low refractive index layer 22d is performed as described later.

In the present embodiment, the film formation chamber C4 is a sputtering film formation chamber. The film forming chamber C4 includes the film forming roller 54 and a plurality of sputtering chambers 60 (sputtering chambers 60a to 60 e) (the number of sputtering chambers 60 is exemplified as 5). The film forming roller 54 is a main guide roller for conveying the working film W in the film forming chamber C4. The film forming roller 54 has a temperature adjusting function capable of heating or cooling the work film W. The sputtering chamber 60 is a space partitioned in the film forming chamber C4. The plurality of sputtering chambers 60 are arranged along the circumferential direction of the film forming roller 54. Each sputtering chamber 60 is opened to the film forming roller 54. A cathode 61 is provided in the sputtering chamber 60. A target (not shown) as a film forming material supply member is disposed on the cathode 61. The target is disposed on the target so as to face the film forming roller 54. Each sputtering chamber 60 is provided with a power supply (not shown) for applying a voltage to the target to generate glow discharge. Examples of the power supply include a DC power supply, an AC power supply, an MF power supply, an RF power supply, and an MF-AC power supply. The MF-AC power source refers to an AC power source with a frequency band of several kHz to several MHz. Each sputtering chamber 60 is connected to a second line (not shown) having a required number of flow rate control valves for introducing gas into the chamber. A predetermined number of guide rollers G for guiding the work film W are provided in the film forming chamber C4.

The connection chamber C5 is disposed between the connection chamber C4 and the film formation chamber C6 in the traveling direction of the work film W. A predetermined number of guide rollers G for guiding the working film W are provided in the connection chamber C5.

The film forming chamber C6 is disposed between the connection chamber C5 and the winding chamber R2 in the traveling direction of the working film W. In the present embodiment, the film formation chamber C6 is a vacuum deposition chamber. The film formation chamber C6 includes a material holding portion 62 and a vapor deposition amount adjustment valve (not shown) capable of controlling the opening degree. The film forming chamber C6 is connected to a vacuum pump, not shown, and is configured to be capable of adjusting the chamber pressure.

A predetermined number of guide rollers G for guiding the work film W are provided in the film forming chamber C6. In such a film forming chamber C6, a film forming step of the antifouling top layer 22e is performed.

A film forming material supply (not shown) is disposed on the material holding portion 62 so as to face the work film W conveyed in the film forming chamber C6. As means for heating the film forming material supply member, the material holding portion 62 may be provided with a resistance heating means, a high-frequency induction heating means, or an electron beam heating means.

With the apparatus Y, a plasma treatment process and a film formation process are sequentially performed. Specifically, the following is described.

The working film W is extracted from the extraction chamber R1. After being drawn out from the drawing chamber R1, the working film W passes through the connection chamber C1, the plasma processing chamber C2, the connection chamber C3, the film forming chamber C4, the connection chamber C5, and the film forming chamber C6 in this order, and is wound in the winding chamber R2. The running speed of the working film W is, for example, 0.5 m/min or more, and is, for example, 15 m/min or less.

The series of lines from the drawing chamber R1 to the winding chamber R2 is not opened to the atmosphere in the middle, and a process under a reduced pressure atmosphere is performed in the lines. The reduced pressure atmosphere is preferably vacuum. The vacuum is preferably a reduced pressure atmosphere of 7Pa or less.

A plasma processing step is performed in the plasma processing chamber C2. In the plasma processing step, the first surface 10a of the substrate film 10 is subjected to plasma processing in a reduced pressure atmosphere in the plasma processing chamber C2 (chamber). In the present embodiment, the plasma treatment is a treatment (oxygen-LAICP treatment) using inductively coupled plasma of an oxygen-containing gas generated by applying high frequency power to LA 71. Specifically, the following is described.

Oxygen is supplied into the plasma processing chamber C2 in the plasma processing through the first line L1. In addition to oxygen, an inert gas may be supplied into the plasma processing chamber C2. Examples of the inert gas include argon, krypton, and xenon. The gas in the plasma processing chamber C2 may contain a gas other than an inert gas. Examples of the other gas 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, further preferably 80% by volume or more, further preferably 90% by volume or more, further preferably 95% by volume or more, and particularly preferably 100% by volume. When the oxygen concentration is equal to or higher than the lower limit value, a high-density oxygen plasma can be generated. This contributes to the nano-scale fine asperity of the first surface 10a of the base film 10 and the high activation by the cleaning of the first surface 10 a.

The pressure (first pressure) in the plasma processing chamber C2 during the plasma processing is preferably 0.1Pa or more, more preferably 0.2Pa or more, still more preferably 0.3Pa or more, and further preferably 7Pa or less, more preferably 5Pa or less, still more preferably 3Pa or less. When the first pressure is equal to or higher than the lower limit value, a plasma environment having a density sufficient for performing the surface modification treatment on the first surface 10a of the substrate film 10 can be formed in the plasma treatment chamber C2 in the plasma treatment. When the first pressure is equal to or lower than the upper limit, thermal damage to the first surface 10a due to excessively high density plasma can be suppressed during the plasma processing, and excessive roughening of the first surface 10a can be suppressed. Suppressing excessive roughening helps to suppress a decrease in mechanical strength of the first face 10 a. The first pressure may be adjusted by the supply amount of oxygen gas into the plasma processing chamber C2.

The frequency of the high-frequency power applied to LA71 in the plasma treatment is preferably 1MHz or more, more preferably 5MHz or more, further preferably 10MHz or more, further preferably 100MHz or less, more preferably 80MHz or less, further preferably 60MHz or less. When the frequency is equal to or higher than the lower limit value, the plasma discharge can be stabilized while the plasma current density is increased in the plasma processing. When the frequency is equal to or lower than the upper limit value, 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 0.1kW or more, more preferably 0.3kW or more, further preferably 1.0kW or more, and further preferably 10kW or less, more preferably 8kW or less, further preferably 6kW or less. When the high-frequency power is equal to or higher than the lower limit value, a high-density plasma environment can be formed in the plasma processing chamber C2 in the plasma processing using the inductively coupled plasma. When the high-frequency power is equal to or less than the upper limit, excessive damage to the substrate by the plasma can be suppressed.

In the plasma treatment step, the plasma current density at the intermediate position between LA71 and substrate film 10 is preferably 1.0mA/cm ³ or more, more preferably 2.0mA/cm ³ or more, still more preferably 3.0mA/cm ³ or more, and further preferably 10mA/cm ³ or less, more preferably 8mA/cm ³ or less, still more preferably 4mA/cm ³ or less. The inductively coupled plasma processing using the low inductance antenna can achieve a higher plasma current density (for example, a plasma density about 100 times higher) than the capacitively coupled plasma processing described above. When the plasma current density is equal to or higher than the lower limit value, sufficient plasma oxygen particles can be ensured in the plasma processing chamber C2 during the plasma processing, and the first surface 10a of the substrate film 10 can be appropriately surface-modified. When the plasma current density is equal to or lower than the upper limit value, damage to the first surface 10a by excessively high-density plasma oxygen particles can be suppressed during the plasma processing.

Examples of the method for adjusting the plasma current density include adjusting the amount of oxygen introduced into the plasma processing chamber C2, adjusting the frequency of the high-frequency power in the high-frequency power supply, and adjusting the magnitude of the applied power.

In the film forming step, first, in the film forming chamber C4, the adhesion layer 21 and the inorganic layer 22 are sequentially formed on the first surface 10a of the base film 10 by sputtering under a reduced pressure atmosphere after the plasma treatment step. The reduced pressure atmosphere is preferably vacuum.

In the sputtering method, a sputtering gas (inert gas) is introduced into each sputtering chamber 60 through a single second line, and a negative voltage is applied to a target (film forming material) disposed on a cathode 61 in the sputtering chamber 60. This causes glow discharge to ionize the gas atoms, so that the gas ions strike the target surface at a high speed, the target material is driven out of the target surface, and the driven target material is deposited on the working film W. Examples of the sputtering gas include argon, krypton, and xenon.

In the case where the film-forming material is a metal oxide, the sputtering method may be a reactive sputtering method. In the reactive sputtering method, oxygen (reactive gas) is introduced into the sputtering chamber 60 in addition to the sputtering gas. Oxygen is introduced into the sputtering chamber 60 via another second line. In the reactive sputtering method, the target is composed of, for example, a metal in the metal oxide forming each layer.

In the sputtering method, the pressure (second pressure) in the sputtering chamber 60 is, for example, 0.1 to 5.0pa depending on the kind of the layer to be formed. The film formation temperature (temperature of the working film W whose temperature is adjusted by the film formation roller 54) is, for example, -10 ℃ to 150 ℃.

In the film forming step, first, the adhesion layer 21 is formed on the base film 10 by sputtering in the sputtering chamber 60 a. In the case of forming an ITO layer as the adhesion layer 21, an ITO target is used as a target on the cathode 61 disposed in the sputtering chamber 60 a. The reactive sputtering is performed while argon and oxygen are introduced into the sputtering chamber 60a (the reactive sputtering is also performed in the following sputtering methods in the sputtering chambers 60b to 60 e).

Next, the high refractive index layer 22a is formed on the adhesion layer 21 by a sputtering method in the sputtering chamber 60 b. In the case of forming the Nb ₂O₅ layer as the high refractive index layer 22a, an Nb target is used as a target on the cathode 61 disposed in the sputtering chamber 60 b.

Next, a low refractive index layer 22b is formed on the high refractive index layer 22a by a sputtering method in the sputtering chamber 60 c. In the case of forming the SiO ₂ layer as the low refractive index layer 22b, a Si target is used as a target on the cathode 61 disposed in the sputtering chamber 60 c.

Next, a high refractive index layer 22c is formed on the low refractive index layer 22b by a sputtering method in the sputtering chamber 60 d. In the case of forming the Nb ₂O₅ layer as the high refractive index layer 22c, an Nb target is used as a target on the cathode 61 disposed in the sputtering chamber 60 d.

Next, the low refractive index layer 22d is formed on the high refractive index layer 22c by a sputtering method in the sputtering chamber 60 e. In the case of forming the SiO ₂ layer as the low refractive index layer 22d, a Si target is used as a target on the cathode 61 disposed in the sputtering chamber 60 e.

In the film forming step, the antifouling top layer 22e is further formed in the film forming chamber C6. In this step, in the film forming chamber C6, the antifouling top layer 22e is formed on the low refractive index layer 22d of the working film W by a vacuum evaporation method as a dry coating method. Specifically, the film forming material supply member (not shown) disposed in the material holding portion 62 is heated to a predetermined temperature in a state where the inside of the film forming chamber C6 is depressurized to a vacuum by the operation of the vacuum pump, and a vacuum vapor deposition method is performed.

In the apparatus Y, after the plasma treatment step and the film formation step, the antireflection film X as the working film W reaches the winding chamber R2 and is wound by the winding roller 52.

As described above, the long antireflection film X can be manufactured.

The anti-reflection layer 22 of the anti-reflection film X may not have the anti-fouling surface layer 22e. In this case, the surface of the low refractive index layer 22d on the opposite side of the base film 10 becomes the surface 22A of the antireflection layer 22. The antireflection film X without the stain-proofing surface layer 22e can be produced by not performing the step in the film forming chamber C6 in the above-described production process of the antireflection film X.

Examples (example)

The present invention will be specifically described with reference to the following examples. However, the present invention is not limited to the examples. The specific values of the blending amount (content), physical property value, parameter and the like described below may be replaced with the upper limit (value defined as "below" or "less than") or the lower limit (value defined as "above" or "exceeding") of the blending amount (content), physical property value, parameter and the like described in the above-described "specific embodiment" corresponding thereto.

[ Example 1]

The antireflection film of example 1 was produced by sequentially performing the following steps.

First, a base film is produced by forming a hard coat layer on one surface of a triacetyl cellulose (TAC) film as a resin film (preparation step). Specifically, first, 100 parts by mass (solid content conversion value, manufactured by DIC corporation) of a butyl acetate solution (product name "LUXYDIR-806", manufactured by BASF corporation) of an ultraviolet curable urethane acrylate resin, 5 parts by mass of a photopolymerization initiator (product name "IRGACURE906", manufactured by BASF corporation) and 0.01 part by mass of a leveling agent (product name "GRANDIC PC4100", manufactured by DIC corporation) were mixed to obtain a mixed solution. Next, a mixed solvent of Cyclopentanone (CPN) and propylene glycol monomethyl ether (PGM) (the mass ratio of CPN to PGM was 45:55) was added to adjust the solid content concentration of the mixed solution to 36 mass%. Thus, a first resin composition was prepared. On the other hand, a long TAC film (product name "KC4UY", thickness 40 μm, manufactured by Konica Minolta ADVANCED LAYERS) was prepared. Next, a first resin composition is applied to one side of the TAC film to form a coating film. Subsequently, the coating film is dried by heating and then cured by irradiation with ultraviolet rays. Thus, a Hard Coat (HC) layer having a thickness of 7 μm was formed on the TAC film.

The heating temperature was set at 90℃and the heating time was set at 1 minute. In the ultraviolet irradiation, a high-pressure mercury lamp was used as a light source, and the coating film was irradiated with ultraviolet rays having a wavelength of 365nm, and the cumulative irradiation light amount was set to 300mJ/cm ². In this manner, a TAC film with an HC layer was produced as a base film.

Next, a plasma treatment process and a subsequent film formation process (roll-to-roll process) are performed on the substrate film while the substrate film is conveyed in a roll-to-roll manner under vacuum. In the plasma treatment step and the film formation step, an apparatus (first apparatus) capable of performing a roll-to-roll process on the working film is used. The first apparatus includes a pumping chamber, a plasma processing chamber (first plasma processing), a first film forming chamber, a second film forming chamber, and a winding chamber. The pumping chamber, the plasma processing chamber, the first film forming chamber, the second film forming chamber, and the winding chamber are disposed in this order and communicate with each other. The extraction chamber is provided with an extraction roller. The roll of the base film as the working film is set on the take-out roller. The plasma processing chamber includes a conveyance roller (conveyance roller 53 in fig. 4) having a temperature adjusting function, and four low inductance antennas (LA 71 in fig. 4 and 5) covered with a cover block (cover block 73 in fig. 5) as shown in fig. 4 and 5. Each low inductance antenna has an extension (extension 71a in fig. 4) parallel to the base film. Of the four low inductance antennas, the extension length d ₁ is 88mm, the maximum length d ₂ (length of extension) is 100mm, the separation distance d ₃ is 112mm, the inter-center distance d ₄ is 290mm, and the inter-center distance d ₅ is 280mm (fig. 4 and 5). Each low inductance antenna was electrically connected to a high frequency power source (RF power source, frequency 13.56 MHz) via an impedance matcher outside the plasma processing chamber. The distance d' between the substrate film travelling in the plasma processing chamber and the cover block was 100mm. The first film forming chamber is a sputtering film forming chamber, and includes a film forming roller (film forming roller 54 in fig. 3) and first to fifth sputtering chambers (sputtering chambers 60a to 60e in fig. 3). Each sputtering chamber is a space partitioned in the first film formation chamber. The first to fifth sputtering chambers are arranged in this order along the circumferential direction of the film forming roller in the traveling direction of the base film. Each sputtering chamber has a cathode disposed opposite to the film forming roller. Each sputtering chamber is connected to a second line (not shown) having a required number of flow rate control valves for introducing gas into the chamber. The second film formation chamber is a vacuum vapor deposition chamber, and includes a material holding portion (in fig. 3, a material holding portion 62). The winding chamber is provided with a winding roller.

In the roll-to-roll process, a plasma treatment is performed on the HC surface (first surface) of the substrate film in a plasma treatment chamber (plasma treatment step). The advancing speed of the base film (film advancing speed) was set to 1.0 m/min. The temperature of the conveying roller with the temperature adjusting function is-8 ℃. The conditions of the plasma treatment are as follows.

After the inside of the apparatus was evacuated until the ultimate vacuum degree of the plasma processing chamber reached 1.0X10 ^－4 Pa, oxygen was introduced into the plasma processing chamber to thereby bring the pressure in the plasma processing chamber to 1.5Pa. An inductively coupled plasma of oxygen-containing gas (the surface of the HC layer of the substrate film was treated with this plasma) was formed around the four low-inductance antennas by applying high-frequency power of 2kW to the antennas by a high-frequency power source. The plasma current density at the intermediate position between the low inductance antenna and the substrate film was 1.3mA/cm ³.

The plasma current density was measured using a langmuir probe for plasma measurement.

In the first film forming 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 are sequentially formed on the substrate film after plasma treatment. Specifically, while the substrate film is being conveyed by the film forming roller in the first film forming chamber while being cooled, an adhesion layer is formed on the HC layer of the substrate film in the first sputtering chamber, a first high refractive index layer is formed on the adhesion layer in the second sputtering chamber, a first low refractive index layer is formed on the first high refractive index layer in the third sputtering chamber, a second high refractive index layer is formed on the first low refractive index layer in the fourth sputtering chamber, and a second low refractive index layer is formed on the second high refractive index layer in the fifth sputtering chamber. The film forming temperature (temperature of the film forming roller) was set to-8 ℃. More specifically, as described below.

In the first sputtering chamber, an ITO layer having a thickness of 4nm was formed as an adhesion layer by a reactive sputtering method. In this step, after the first film formation chamber was evacuated until the final vacuum degree reached 1.0X10 ^－4 Pa, argon as an inert gas and oxygen as a reactive gas were introduced into the first sputtering chamber so that the pressure in the first sputtering chamber became 0.2Pa. The oxygen introduction amount was set to 10 parts by volume per 100 parts by volume of argon introduced into the first sputtering chamber. A sintered body of indium oxide and tin oxide (ITO with a tin oxide concentration of 10 mass%) was used as a target. As a power source for applying a voltage to the target, MF-AC power (the same applies to second to fifth sputtering chambers described later) is used. The discharge power was set to 4.3kW.

In the second sputtering chamber, a Nb ₂O₅ layer (refractive index 2.33) having a thickness of 14nm was formed as a first high refractive index layer by a reactive sputtering method. In this step, after the first film formation chamber was evacuated in the above manner, argon as an inert gas and oxygen as a reactive gas were introduced into the second sputtering chamber so that the pressure in the second sputtering chamber became 0.5Pa. The oxygen introduction amount was set to 5 parts by volume per 100 parts by volume of argon introduced into the second sputtering chamber. Nb target was used as target. The discharge power was set to 13kW.

In the third sputtering chamber, a SiO ₂ layer (refractive index 1.46) having a thickness of 28nm was formed as the first low refractive index layer by a reactive sputtering method. In this step, after the first film formation chamber was evacuated in the above manner, argon as an inert gas and oxygen as a reactive gas were introduced into the third sputtering chamber so that the pressure in the third sputtering chamber became 0.2Pa. The oxygen introduction amount was set to 30 parts by volume per 100 parts by volume of argon introduced into the third sputtering chamber. Si target was used as target. The discharge power was set to 25kW.

In the fourth sputtering chamber, a Nb ₂O₅ layer (refractive index 2.33) having a thickness of 105nm was formed as a second high refractive index layer by a reactive sputtering method. In this step, after the first film formation chamber was evacuated in the above manner, argon as an inert gas and oxygen as a reactive gas were introduced into the fourth sputtering chamber so that the pressure in the fourth sputtering chamber became 0.5Pa. The oxygen introduction amount was set to 13 parts by volume per 100 parts by volume of argon introduced into the fourth sputtering chamber. Nb target was used as target. The discharge power was set to 27.5kW.

In the fifth sputtering chamber, a SiO ₂ layer (refractive index 1.46) having a thickness of 84nm was formed as a second low refractive index layer by a reactive sputtering method. In this step, after the first film formation chamber was evacuated in the above manner, argon as an inert gas and oxygen as a reactive gas were introduced into the fifth sputtering chamber so that the pressure in the fifth sputtering chamber became 0.2Pa. The oxygen introduction amount was set to 30 parts by volume per 100 parts by volume of argon introduced into the fifth sputtering chamber. Si target was used as target. The discharge power was set to 20.5kW.

In the second film forming chamber, an antifouling surface layer is formed on the second low refractive index layer. Specifically, an anti-fouling surface layer having a thickness of 8nm was formed on the second low refractive index layer by vacuum vapor deposition using an alkoxysilane compound containing a perfluoropolyether group as a vapor deposition source. The vapor deposition source is a solid component obtained by drying "Optool UD509" (the concentration of the solid component is 20 mass%) of the perfluoropolyether group-containing alkoxysilane compound represented by the above general formula (2) manufactured by Dain industries, ltd. The heating temperature of the vapor deposition source in the vacuum vapor deposition method was set to 260 ℃.

As described above, the antireflection film of example 1 was produced. The antireflection film of example 1 includes a base film having an HC layer, an adhesion layer on the HC layer, and an antireflection layer (first high refractive index layer/first low refractive index layer/second high refractive index layer/second low refractive index layer/antifouling surface layer) on the adhesion layer. The HC layer surface of the base film of the antireflection film of example 1 was subjected to plasma treatment. The plasma treatment is a treatment (oxygen-LAICP treatment) using inductively coupled plasma using an oxygen-containing gas, which is generated by applying high-frequency power to a low-inductance antenna.

[ Example 2]

An antireflection film of example 2 was produced in the same manner as that of example 1, except for the following points. In the preparation process, the second resin composition is used instead of the first resin composition, and the HC layer is formed on the TAC film. Specifically, the following is described.

In the preparation step, first, 17 parts by mass (solid content equivalent) of an acrylic monomer composition containing nano silica particles (product name "NC035HS", nano silica concentration 60% by mass, manufactured by the grongchuan chemical industry Co., ltd.), 83 parts by mass (solid content equivalent) of an ultraviolet curable polyfunctional urethane acrylate (product name "BEAMSET580", solid content concentration 70% by mass, manufactured by grongchuanchemical industry Co., ltd.), 1.5 parts by mass (solid content equivalent), 1.5 parts by mass of a photopolymerization initiator (product name "OMNIRAD127D", manufactured by IGM RESINS), 0.15 parts by mass (product name "LE303", solid content concentration 40% by mass, manufactured by grongchuanchuang chemical Co., ltd.), and butyl acetate were mixed to prepare a second resin composition having a solid content of 42% by mass. On the other hand, a long TAC film (product name "KC4UY", thickness 40 μm, manufactured by Konica Minolta ADVANCED LAYERS) was prepared. Next, a second resin composition is applied to one side of the TAC film to form a coating film. Subsequently, the coating film is dried by heating and then cured by ultraviolet irradiation. Thus, an HC layer having a thickness of 7 μm was formed on the TAC film. The heating temperature was set at 90 ℃ and the heating time was set at 1 minute. In the ultraviolet irradiation, a high-pressure mercury lamp was used as a light source, and the coating film was irradiated with ultraviolet rays having a wavelength of 365nm, and the cumulative irradiation light amount was set to 300mJ/cm ². In this manner, a TAC film with an HC layer was produced as a base film. The HC layer of the substrate film of example 2 contained 10 mass% of nano silica particles.

[ Example 3]

An antireflection film of example 3 was produced in the same manner as that of example 1, except for the following points. In the preparation process, the following resin composition was used instead of the first resin composition, and the HC layer was formed on the TAC film. Specifically, the following is described.

In the preparation step, 80 parts by mass (solid content equivalent) of an ultraviolet curable urethane acrylate resin (product name "UT-7314", manufactured by mitsubishi chemical company), 20 parts by mass (solid content equivalent) of a multifunctional acrylate containing pentaerythritol triacrylate as a main component (product name "VISCOAT #300", manufactured by osaka organic chemical industry company), 1.5 parts by mass of a photopolymerization initiator (product name "Omnirad127D", manufactured by BASF company), and 0.06 parts by mass of a leveling agent (product name "Polyflow LE-303", a leveling agent containing a silicone compound, manufactured by co-mingling chemical company) were mixed to obtain a mixed solution. Then, a mixed solvent of butyl acetate and Cyclopentanone (CPN) was added as a solvent (the mass ratio of butyl acetate to CPN was 70:30) to the mixed solution to prepare a resin composition having a solid content concentration of 40 mass%.

Comparative example 1

An antireflection film of comparative example 1 was produced in the same manner as that of example 1, except for the following points. In the plasma processing step, argon is introduced into the plasma processing chamber in place of oxygen to perform plasma processing. The plasma treatment is a treatment (Ar-LAICP treatment) using inductively coupled plasma of argon-containing gas, which is generated by applying high-frequency power to a low-inductance antenna.

Comparative example 2

First, as in the preparation process in example 1, an HC layer was formed on one surface of a TAC film, and a base film (TCA film/HC layer) was produced.

Next, a plasma treatment process and a subsequent film formation process (roll-to-roll process) are performed on the substrate film while the substrate film is conveyed in a roll-to-roll manner under vacuum. In the plasma treatment step and the film formation step, a second apparatus capable of performing a roll-to-roll process on the working film is used. The second apparatus has the same structure as the first apparatus except that it includes a second plasma processing chamber instead of the first plasma processing chamber. The second plasma processing chamber includes a cathode electrode and an anode electrode (both rectangular electrodes made of SUS 304) as a pair of planar electrodes for plasma generation. The pair of planar electrodes are disposed parallel to the substrate film passing through the second plasma processing chamber at intervals of 50 mm. The anode electrode was disposed at a position 35mm apart from the substrate film passing through the plasma processing chamber, and was grounded outside the plasma processing chamber. The cathode electrode was disposed so as to face the HC layer surface of the base film, and was electrically connected to a high-frequency power source (RF power source, 13.56 MHz) via an impedance matcher. The length of each electrode facing the base film in the film advancing direction was 110mm, and the length in the width direction was 430mm.

In the second plasma processing chamber, the HC surface (first surface) of the substrate film is subjected to plasma processing (bombardment processing). The advancing speed of the base film (film advancing speed) was set to 1.0 m/min. The conditions of the plasma treatment are as follows.

After the inside of the apparatus was evacuated until the ultimate vacuum degree of the second plasma processing chamber reached 1.0X10 ^－4 Pa, argon was introduced into the second plasma processing chamber so that the pressure in the plasma processing chamber became 0.5Pa. A power of 550W is applied between the planar electrodes by a high frequency power supply, thereby generating a Capacitively Coupled Plasma (CCP). In this plasma environment, the HC layer surface of the base film was subjected to bombardment treatment (Ar-BB treatment) with argon ions.

In the first film formation chamber, an adhesive layer was formed in this order to a second low refractive index layer on the substrate film after the plasma treatment in the same manner as described in example 1. In the second film formation chamber, an antifouling surface layer was formed on the second low refractive index layer in the same manner as described in the above-described embodiment 1.

[ Comparative example 3]

An antireflection film of comparative example 3 was produced in the same manner as that of comparative example 2, except for the following points. In the preparation process, the third resin composition is used instead of the first resin composition, and the HC layer is formed on the TAC film. Specifically, the following is described.

In the preparation step, first, 83 parts by mass (solid content equivalent) of an acrylic monomer composition (product name "NC035HS", nano silica concentration 60% by mass, manufactured by the institute of chemical industry, and in the state of being incorporated by reference), 17 parts by mass (solid content equivalent) of an ultraviolet-curable polyfunctional urethane acrylate (product name "BEAMSET580", solid content concentration 70% by mass, manufactured by the institute of chemical industry, and in the state of being incorporated by reference), 1.5 parts by mass (solid content equivalent), 1.5 parts by mass of a photopolymerization initiator (product name "Omnirad127D", manufactured by IGM RESINS), 0.15 parts by mass (product name "LE303", solid content concentration 40% by mass, manufactured by the institute of chemical company, and butyl acetate were mixed to prepare a second resin composition having a solid content of 42% by mass. On the other hand, a long TAC film (product name "KC4UY", thickness 40 μm, manufactured by Konica Minolta ADVANCED LAYERS) was prepared. Next, a second resin composition is applied to one side of the TAC film to form a coating film. Subsequently, the coating film is dried by heating and then cured by irradiation with ultraviolet rays. Thus, an HC layer having a thickness of 4 μm was formed on the TAC film. The heating temperature was set at 90℃and the heating time was set at 1 minute. In the ultraviolet irradiation, a high-pressure mercury lamp was used as a light source, and the film was irradiated with ultraviolet rays having a wavelength of 365nm, and the cumulative irradiation light amount was set to 300mJ/cm ². In this manner, a TAC film with an HC layer was produced as a base film. The HC layer of the base film in comparative example 3 contained 50 mass% of nano silica particles.

[ Comparative example 4]

An antireflection film of comparative example 4 was produced in the same manner as that of comparative example 2, except for the following points. In the preparation step, the second resin composition was used in place of the first resin composition, and an HC layer (nano silica particle content 10 mass%) was formed on the TAC film.

< Surface Property >

The surface properties of the surfaces of the antireflection layers were examined for the antireflection films of examples 1 to 3 and comparative examples 1 to 4. Specifically, the exposed surface of the antireflection layer in the antireflection film was first observed and photographed (first observation) by an atomic force microscope (trade name "Dimention Edge SPC-160113-01", manufactured by Bruker corporation). In the observation, the measurement mode was set to the tapping mode, and an antimony doped silicon cantilever (trade name "RTESP-300", manufactured by Bruker corporation) was used as a probe (condition for the first observation). Next, from the observation image of 1 μm square, the surface roughness (arithmetic mean height) Sa, the spread area ratio Sdr, the maximum peak height Sp, the maximum valley depth Sv, and the root mean square slope Sdq were obtained. These are parameters based on ISO 25178-2:2012. Table 1 shows the surface roughness Sa (nm), the spread area ratio Sdr (%), the difference between the maximum peak height Sp (nm) and the maximum valley depth Sv (nm), and the root mean square slope Sdq for the surface of the antireflection layer.

On the other hand, the surface properties of the first surface of the base film were examined for each of the antireflection films of examples 1 to 3 and comparative examples 1 to 4. Specifically, first, during the production of the antireflection film, a substrate film after plasma treatment and before formation of the adhesion layer is sampled, and a first surface (second surface) of the substrate film is observed and photographed using the atomic force microscope. The conditions for the second observation are the same as those for the first observation described above. Next, from the observation image of 1 μm square, the surface roughness (arithmetic mean height) Sa, the spread area ratio Sdr, the maximum peak height Sp, the maximum valley depth Sv, and the root mean square slope Sdq were obtained. Table 1 shows the surface roughness Sa (nm), the spread area ratio Sdr (%), the difference between the maximum peak height Sp (nm) and the maximum valley depth Sv (nm), and the root mean square slope Sdq for the first surface of the base material film.

< Measurement of reflectance >

The total reflectance and the regular reflectance of each of the antireflection films of examples 1 to 3 and comparative examples 1 to 4 were measured in the following manner.

First, the side of the antireflection film opposite to the antireflection layer side was adhered to a black acrylic plate (thickness 2 mm) with a predetermined transparent acrylic adhesive. Thus, a laminated film was obtained. Next, the measurement membrane was cut out from the laminated film. Next, the spectrum of the total reflection light (including the regular reflection light) was measured (first reflectance measurement) for the film by a spectrophotometer (product name "UH4150", manufactured by hitachi high technology). In the measurement, a standard light source D65 was used as a light source, and a membrane was set in a spectrophotometer so that light was irradiated to the membrane from the antireflection layer side thereof. The measurement was performed in the integrating sphere measurement mode of the spectrophotometer. The measured reflectance is the total reflectance of the film (antireflection film) on the antireflection layer side of the irradiation light having a wavelength of 380nm to 780nm from the standard light source D65.

The measurement results are shown in Table 1. Further, the spectrum of the specular light was measured (second reflectance measurement) for the film using a spectrophotometer (UH 4150). The measurement conditions are the same as those of the first reflectance measurement. Then, the difference Δr between the total reflectance and the regular reflectance of the irradiation light having a wavelength of 450nm was obtained based on the spectrum obtained by the first reflectance measurement and the spectrum obtained by the second reflectance measurement. The results are shown in Table 1.

< Adhesion >

The following first test and second test were performed for each of the antireflection films of examples 1 to 3 and comparative examples 1 to 4, and the adhesion of the antireflection layer was examined.

First, the substrate film side of the antireflection film was fixed to a glass plate. Then, the antireflection layer of the antireflection film on the glass plate was irradiated with light (for promoting weather resistance test) at a temperature of 85℃and a relative humidity of 45% for 32.5 hours under conditions of an irradiation intensity (integrated illuminance of 290nm to 450 nm) of 150mW/cm ². The test was performed by "Eye Super UV Tester SUV-W161" manufactured by Kawasaki electric Co.

In the second test, first, 11 parallel first cuts (2 mm intervals) extending straight in the first direction and 11 parallel second cuts (2 mm intervals) extending straight in the second direction orthogonal to the first direction were formed in the antireflection layer and the sealing layer in the antireflection film on the glass plate after the first test by a dicing blade, and 100 squares were formed from the first cuts and the second cuts. Next, isopropyl alcohol was continuously dropped at 2mL/min in the region of 100 squares of the antireflection film, while a polyester wiper (product name "Anticon Gold", manufactured by SANPLATEC company) was slid on the region of 100 squares under conditions of 20mm×20mm wiper contact surface, 1.5kg/20mm ∈of load ∈of ∈, sliding speed of 50 mm/sec, and reciprocation of 1000. Next, the number of peeled off tiles of 1mm ² or more out of 100 tiles was counted. Next, the peeling rate (%) was calculated by dividing the count value by 100.

The case where the peeling rate was less than 10% was evaluated as "excellent", the case where the peeling rate was 10% or more and less than 20% was evaluated as "good", the case where the peeling rate was 20% or more and less than 80% was evaluated as "poor", and the case where the peeling rate was 80% or more was evaluated as "remarkably poor". The results are shown in Table 1.

[ Evaluation ]

In the antireflection film of comparative example 1, since the HC layer of the base film does not contain particles, the surface of the base film does not have irregularities due to the particles. The plasma treatment in the process of producing the antireflective film of comparative example 1 was a treatment using inductively coupled plasma using argon-containing gas (Ar-LAICP treatment) as described above. According to Ar-LAICP treatment, the surface of the substrate film could not be roughened compared with the oxygen-LAICP treatment. In such an antireflection film of comparative example 1, adhesion of the antireflection layer cannot be ensured.

In the antireflection film of comparative example 2, since the HC layer of the base film does not contain particles, the surface of the base film does not have irregularities due to the particles. The plasma treatment in the process of producing the antireflective film of comparative example 2 was an ion bombardment treatment (Ar-BB treatment) using capacitively coupled plasma using an argon-containing gas as described above. According to the Ar-BB treatment, the surface of the substrate film could not be roughened compared with the oxygen-LAICP treatment. In such an antireflection film of comparative example 2, adhesion of the antireflection layer cannot be ensured.

In the antireflection film of comparative example 3, the HC layer of the base film contained 50 mass% of the nano silica particles. The HC layer surface (surface on the adhesion layer 21 side) of the base film 10 had irregularities due to particles, and the surface roughness Sa was 7.65nm and large. Therefore, in the antireflection film of comparative example 3, the surface roughness Sa of the antireflection layer was 5.01nm, which was large. Therefore, the total reflectance of the antireflection film of comparative example 3 was 0.46%, which was large.

In the antireflective film of comparative example 4, good adhesion cannot be obtained with respect to the antireflective layer. Such a film cannot continuously obtain a good reflection suppressing effect.

In the antireflection film of example 1, the HC layer of the base film contains no particles. Therefore, the HC layer surface (surface on the adhesion layer 21 side) of the base film does not have irregularities due to particles. Therefore, in the antireflection film of example 1, the surface roughness Sa of the antireflection layer was 1.53nm, which was small. Therefore, the total reflectance of the antireflection film of example 1 was 0.31%, which is smaller than the total reflectance (0.46%) in comparative example 3. Further, as described above, the plasma treatment in the manufacturing process of the antireflection film of example 1 is a treatment (oxygen-LAICP treatment) using inductively coupled plasma of oxygen-containing gas generated by applying high-frequency power to a low-inductance antenna. According to the oxygen-LAICP treatment, the surface of the base film can be roughened with fine irregularities on the nanometer scale as compared with the Ar-LAICP treatment and the Ar-BB treatment. Therefore, in the antireflection film of example 1, adhesion of the antireflection layer can be ensured. Therefore, according to the antireflection film of example 1 (the total reflectance is low and the adhesiveness of the antireflection layer is ensured), a good reflection suppressing effect can be continuously obtained. The same is true in example 3.

In the antireflection film of example 2, the HC layer of the base film contains particles. However, since the content of the particles is small, the HC layer surface (surface on the adhesion layer 21 side) of the base film does not have irregularities due to the particles. Therefore, in the antireflection film of example 2, the surface roughness Sa of the antireflection layer was 1.50nm, which was small. Therefore, the total reflectance of the antireflection film of example 2 was 0.33%, which is smaller than the total reflectance (0.46%) in comparative example 3. Further, as described above, the plasma treatment in the manufacturing process of the antireflection film of example 2 is the oxygen-LAICP treatment. Therefore, in the antireflection film of example 2, adhesion of the antireflection layer can be ensured. Therefore, according to the antireflection film of example 2 (the total reflectance is low and the adhesiveness of the antireflection layer is ensured), a good reflection suppressing effect can be continuously obtained.

TABLE 1

The present invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be construed as limiting. Variations of the invention that are obvious to a person skilled in the art are included within the scope of the claims.

Industrial applicability

The antireflection film of the present invention is suitable for use in the manufacture of display devices such as liquid crystal displays and organic EL displays.

Description of the reference numerals

X is an antireflection film, H is a thickness direction, D is a plane direction, 10 is a base material film, 10a is a first face, 10b is a second face, 11 is a resin film, 12 is a cured resin layer, 21 is an adhesion layer, 22 is an antireflection layer, 22a and 22c are high refractive index layers, 22b and 22D are low refractive index layers, and 22e is an antifouling surface layer.

Claims

1. An antireflection film comprising a base film, an adhesion layer on the base film, and an antireflection layer on the adhesion layer,

The total reflectance of the irradiation light with the wavelength of 380-780 nm from the standard light source D65 to the anti-reflection layer side is below 0.40%,

The peeling rate of the antireflection layer in the following second test after the following first test was less than 20%,

First test:

Firstly, fixing one side of the substrate film of the anti-reflection film on a glass plate, then, irradiating the anti-reflection layer of the anti-reflection film on the glass plate with light for 32.5 hours under the conditions of a temperature of 85 ℃, a relative humidity of 45% and an irradiation intensity of 150mW/cm ² and a cumulative illuminance of 290nm to 450nm,

Second test:

Firstly, forming 11 parallel first cuts extending straight in a first direction and having a spacing of 2mm and 11 parallel second cuts extending straight in a second direction orthogonal to the first direction and having a spacing of 2mm by using a cutter in the antireflection film and the sealing layer on the glass plate, forming 100 squares from the first cuts and the second cuts, then continuously dropping isopropyl alcohol at 2 mL/min to the 100 square area of the antireflection film while sliding a polyester wiper on the 100 square area with a wiper contact surface of 20mm×20mm, a load of 1.5kg/20mm ∈ and a sliding speed of 50 mm/sec, and 1000 reciprocations, then counting the number of peeled squares generating 1mm ² or more from the 100 squares, and then dividing the count value by 100 to calculate a peeling rate in% of the peeling rate.

2. The antireflection film as claimed in claim 1, wherein,

The difference between the total reflectance and the regular reflectance of the irradiation light having a wavelength of 450nm on the antireflection layer side is 0.25% or less.

3. The antireflection film as claimed in claim 1, wherein,

The surface roughness Sa of the surface of the anti-reflection layer on the opposite side of the base film is 4.5nm or less.

4. The antireflection film as claimed in claim 1, wherein,

The spread area ratio Sdr of the surface of the antireflection layer on the opposite side of the base film is 3.0% or less.

5. The antireflection film as claimed in claim 1, wherein,

The difference between the maximum peak height Sp and the maximum valley depth Sv of the surface of the anti-reflection layer on the side opposite to the base film is 30nm or less.

6. The antireflection film as claimed in claim 1, wherein,

The surface of the antireflection layer opposite to the base film has a root mean square slope Sdq of 12 or less.

7. The antireflection film as claimed in any one of claims 1 to 6, wherein,

The surface roughness Sa of the surface of the base film on the antireflection layer side is 1.0nm or more and 4.0nm or less.

8. The antireflection film as claimed in any one of claims 1 to 6, wherein,

The spread area ratio Sdr of the surface of the base film on the antireflection layer side is 2.0% or more and 10% or less.

9. The antireflection film as claimed in any one of claims 1 to 6, wherein,

The difference between the maximum peak height Sp and the maximum valley depth Sv of the surface of the substrate film on the side of the anti-reflection layer is 10nm to 50 nm.

10. The antireflection film as claimed in any one of claims 1 to 6, wherein,

The root mean square slope Sdq of the surface of the base material film on the antireflection layer side is 12 to 30.