Barrier film, laminate, wavelength conversion sheet, backlight member, and display device

Abstract

Provided are: a barrier film having a high luminance maintenance rate when used for a wavelength conversion sheet; and a wavelength conversion sheet and a backlight member using the same.　The present invention provides a barrier film in which a resin substrate, a first aluminum oxide vapor deposition film, a first coating layer, a second aluminum oxide vapor deposition film, and a second coating layer are laminated in this order, wherein: each of the first and second coating layers is a cured product of a resin composition containing an alkoxysilane and a hydroxyl group-containing water-soluble resin; and the first and second aluminum oxide vapor deposition films have a vapor deposition film peak top ratio P of 0.70 or greater and less than 1.05 when an X-ray absorption fine structure analysis is performed.　P = (intensity peak top around 1572 eV) / (intensity peak top around 1566 eV)

Description

Barrier film, laminate, wavelength conversion sheet, backlight member, display device

[0001] The present invention relates to a barrier film, a laminate, a wavelength conversion sheet, a backlight member, and a display device.

[0002] Conventionally, laminated films having a film formed on a substrate such as a long film or sheet of plastic have been used in various applications. For example, a barrier laminated film has been developed in which a barrier layer made of a thin film of aluminum oxide or the like is provided on a plastic film to provide a barrier function against oxygen and water vapor.

[0003] As a method for producing a barrier film having an aluminum oxide thin film, for example, Patent Document 1 discloses a gas barrier film having excellent transparency and gas barrier properties, which is obtained by using a plasma activated vapor deposition method (a so-called plasma-assisted method during vapor deposition) in which high-density plasma is generated in a space between an aluminum evaporation source and a polymer film.

[0004] Furthermore, Patent Document 2 discloses an aluminum oxide vapor-deposited film in which a vapor-deposited film of low aluminum oxide is formed on a transparent plastic film, which is then subjected to a plasma treatment containing oxygen gas to form a vapor-deposited film of high aluminum oxide, which is then further subjected to a heat treatment at high humidity to form a vapor-deposited film of aluminum hydroxide.

[0005] Meanwhile, development of backlight components using quantum dot technology is also underway as an application of the above-mentioned barrier films. Quantum dots are nanometer-sized semiconductor particles. Furthermore, quantum dots can adjust their emission wavelength across the entire visible range by adjusting their size due to the quantum confinement effect (quantum size effect), in which electrons and excitons are confined within small nanometer-sized crystals. Quantum dots are phosphors that can generate strong fluorescence in a narrow wavelength band, enabling display devices to illuminate with light of the three primary colors with excellent color purity. Therefore, backlights using quantum dots can produce display devices with excellent color reproducibility.

[0006] The wavelength conversion sheet used in the backlight light source of this display device has a configuration in which a phosphor layer in which nanometer-sized semiconductor particles are dispersed in a resin layer, and barrier films are laminated on both surfaces of the phosphor layer to suppress deterioration of the phosphor layer, and is combined with an LED light source.

[0007] For example, a wavelength conversion sheet in which a barrier film is laminated on a phosphor layer containing a phosphor, the barrier film being a predetermined polyethylene terephthalate film on one side thereof, and a backlight unit using the same have been developed (Patent Document 3). The wavelength conversion sheet using a barrier film with excellent barrier properties and transparency can provide a display device with more natural, vivid colors and excellent color tone.

[0008] JP 2017-177343 JP 11-170427 WO 2015 / 037733

[0009] In wavelength conversion sheets such as those disclosed in Patent Document 3, further improvements in the oxygen barrier property and water vapor barrier property of the barrier film are required to suppress deterioration of the phosphor layer. In particular, the luminance of the wavelength conversion sheet decreases over time due to deterioration of the phosphor layer. Therefore, in order to maintain the luminance of the wavelength conversion sheet for a long period of time, a particularly high level of barrier property is required.

[0010] An object of the present invention is to provide a barrier film that is suitably used for an optical film such as a wavelength conversion sheet, a wavelength conversion sheet using the barrier film, and a backlight member using the wavelength conversion sheet.

[0011] As a result of intensive studies to solve the above problems, the present inventors have found that the luminance maintenance factor can be increased when a barrier film is used in a wavelength conversion sheet by focusing on the amount of hydroxyl groups in an aluminum oxide thin film obtained by X-ray absorption fine structure analysis (hereinafter simply referred to as XAFS), and have thus completed the present invention.

[0012] Specifically, the present invention provides the following:

[0013] (1) A barrier film comprising a resin substrate, a first aluminum oxide vapor-deposited film, a first coating layer, a second aluminum oxide vapor-deposited film, and a second coating layer laminated in this order, wherein the first coating layer and the second coating layer are each a cured product of a resin composition containing an alkoxysilane and a hydroxyl group-containing water-soluble resin, and wherein the first aluminum oxide vapor-deposited film and the second aluminum oxide vapor-deposited film have a vapor-deposited film peak top ratio P, defined as follows, of 0.70 or more and less than 1.05 when X-ray absorption fine structure analysis is performed from the surface side of the second coating layer of the barrier film: P = (intensity peak top near 1572 eV) / (intensity peak top near 1566 eV).

[0014] (2) The barrier film according to (1), wherein when the barrier film is etched from the surface opposite to the resin substrate by time-of-flight secondary ion mass spectrometry (TOF-SIMS), the coating layer intensity ratios X, defined as follows, detected in the respective regions of the first coating layer and the second coating layer are 0.50 or more and 1.10 or less, respectively: X=C ２ － Ionic strength / Si － Ionic strength

[0015] (3) The barrier film according to (1), wherein a matte layer is disposed on the resin substrate on the side opposite to the first aluminum oxide vapor-deposited film.

[0016] (4) A laminate in which the barrier film according to (1) and a support are laminated via an adhesive layer.

[0017] (5) The laminate according to (4), wherein a matte layer is disposed on the opposite side of the support from the adhesive layer.

[0018] (6) A wavelength conversion sheet in which the barrier films according to (3) are arranged on both sides of a phosphor layer, sandwiching the phosphor layer therebetween.

[0019] (7) A wavelength conversion sheet in which the laminate according to (4) is arranged on both sides of a phosphor layer, and the laminates are arranged in the order of the support, the resin base material, the coating layer, and the phosphor layer from the outermost layer side.

[0020] (8) A wavelength conversion sheet in which the laminate according to (4) is arranged on both sides of a phosphor layer, and the laminates are arranged in the order of the support, the covering layer, the resin base material, and the phosphor layer from the outermost layer side.

[0021] (9) A wavelength conversion sheet in which the laminates according to (4) are arranged on both sides of a phosphor layer, one laminate being arranged in the order of the support, the resin base material, the coating layer, and the phosphor layer from the outermost layer side, and the other laminate being arranged in the order of the support, the coating layer, the resin base material, and the phosphor layer from the outermost layer side.

[0022] (10) A backlight member comprising a light source, a light guide plate or a diffusion plate, and the wavelength conversion sheet according to (6).

[0023] (11) A surface-mounted display device including a light guide plate, the display device including a liquid crystal panel, a polarized light selective reflection sheet, a prism sheet, the wavelength conversion sheet according to (6), the light guide plate, and a reflection sheet stacked in this order, and a light source unit disposed on an end surface of the light guide plate.

[0024] (12) A direct-type display device including a diffusion plate, the display device including a liquid crystal panel, a polarized light selective reflection sheet, a prism sheet, the wavelength conversion sheet according to (6), the diffusion plate, a light source unit, and a reflection sheet laminated in this order.

[0025] When the barrier film of the present invention is used in a wavelength conversion sheet, it can increase the luminance maintenance rate.

[0026] 1. A cross-sectional view showing an example of a barrier film according to the present embodiment. A diagram showing an example of a film forming apparatus according to an embodiment of the present invention. A cross-sectional view showing an example of a plasma pretreatment mechanism of the film forming apparatus. A plan view showing an example of an electrode unit and a magnetic field forming unit of the plasma pretreatment mechanism of the film forming apparatus. A cross-sectional view showing an example of an electrode unit and a magnetic field forming unit of the plasma pretreatment mechanism of the film forming apparatus. A cross-sectional view showing an example of a film forming mechanism of the film forming apparatus. A cross-sectional view showing an example of a laminate using the barrier film of the present invention. A cross-sectional view showing another example of a laminate using the barrier film of the present invention. A cross-sectional view showing another example of a laminate using the barrier film of the present invention. A cross-sectional view showing an example of a wavelength conversion sheet using the barrier film of the present invention. A cross-sectional view showing another example of a wavelength conversion sheet using the barrier film of the present invention. A perspective view schematically showing the configuration of a surface-mounted display device according to an embodiment of the present invention. A cross-sectional view of the display device shown in FIG. 10. A cross-sectional view schematically showing the configuration of a direct-type display device according to an embodiment of the present invention. A diagram showing an XAFS spectrum of the barrier film of Example 3. A diagram showing the analysis result of the XAFS spectrum of the barrier film of Example 3. A diagram showing the analysis result of the XAFS spectrum of the barrier film of Comparative Example 2. FIG. 1 shows the results of XAFS spectrum analysis for the barrier film of Comparative Example 4. FIG. 2 shows the results of XAFS spectrum analysis for the barrier film of Comparative Example 10. FIG. 3 shows the results of TOF-SIMS spectrum for the barrier film of Example 3. FIG. 4 shows the results of TOF-SIMS spectrum for the barrier film of Comparative Example 10. FIG. 5 shows the results of TOF-SIMS spectrum for the barrier film of Comparative Example 11.

[0027] Specific embodiments of the present invention will be described in detail below, but the present invention is not limited to the following embodiments and can be practiced with appropriate modifications within the scope of the object of the present invention. Furthermore, in this specification, the expression "A to B" (A and B are arbitrary numerical values) means "at least AX and at most B."

[0028] FIG. 1 is a cross-sectional view showing an example of a barrier film according to the present embodiment. A barrier film manufactured using the film formation apparatus according to the present embodiment includes, for example, a substrate 120, a first vapor-deposited film 131b, a first coating layer 131a, a second vapor-deposited film 132b, and a second coating layer 132a, as in the barrier film 100A shown in FIG. 1. In the example shown in FIG. 1, the first vapor-deposited film 131b is located on one surface of the substrate 120. In the example shown in FIG. 1, the barrier film 100A is formed by laminating the substrate 120, the first vapor-deposited film 131b, the first coating layer 131a, the second vapor-deposited film 132b, and the second coating layer 132a in this order, with the second coating layer 132a being located on the surface of the barrier film. First vapor-deposited film 131b, first coating layer 131a, second vapor-deposited film 132b, and second coating layer 132a constitute barrier layer 130. In the following description, the first aluminum oxide vapor-deposited film and the second aluminum oxide vapor-deposited film will be simply referred to as the first vapor-deposited film and the second vapor-deposited film, respectively.

[0029] In this specification, "laminated in this order" means that the substrate, the first vapor-deposited film, the first coating layer, the second vapor-deposited film, and the second coating layer are laminated in this order, and other layers such as an anchor coat layer or a primer layer may be laminated between these layers.

[0030] Each layer constituting the barrier film 100A will be described below.

[0031] [Substrate] The substrate 120 is a layer made of a resin. There are no particular limitations on the resin, and known resin films or sheets can be used. Specifically, a polyester substrate or a polyolefin substrate may be used. As the polyester substrate, for example, a polyester resin including a polyethylene terephthalate resin, a polybutylene terephthalate resin, a polyethylene naphthalate resin, or the like can be used. As the polyolefin substrate, for example, a polypropylene resin can be used.

[0032] Among polyester-based resins, polyethylene terephthalate-based resins and polybutylene terephthalate-based resins are preferably used. The polyester film used as the substrate 120 may be stretched in a predetermined direction. In this case, the polyester film may be a uniaxially stretched film stretched in one predetermined direction, or a biaxially stretched film stretched in two predetermined directions. For example, when a film made of polyethylene terephthalate is used as the substrate 120, a biaxially stretched polyethylene terephthalate film can be used.

[0033] When a film made of polypropylene resin is used as the substrate 120, a biaxially oriented polypropylene film can be used.

[0034] In the case of polyester films, the film thickness is not particularly limited as long as it allows pretreatment and film formation treatment when forming a vapor-deposited film using a film-forming apparatus described below, but from the viewpoint of flexibility and shape retention, the film thickness is preferably in the range of 5 μm to 100 μm, and more preferably in the range of 10 μm to 50 μm. When the polyester film has a thickness within the above range, it is easy to bend and does not tear during transportation, and is easy to handle in a film-forming apparatus used to produce a barrier film having a vapor-deposited film.

[0035] As the polyethylene terephthalate film (PET film), in addition to conventionally known PET films, biomass PET films, recycled PET films, and high-stiffness PET films (tough PET films) may be used as the substrate. The film may have a single layer or a multilayer structure of two or more layers, and in the case of a multilayer structure, the layers may have the same composition or different compositions. In the case of a multilayer structure, the layers may be bonded together via an adhesive layer or the like.

[0036] In the case of a polyolefin film, the film thickness is preferably in the range of 10 μm to 100 μm, more preferably in the range of 15 μm to 50 μm, from the viewpoint of flexibility and shape retention.

[0037] The substrate 120 may have an anchor coat layer (AC layer, also called a primer layer) formed on its surface to enhance adhesion with the vapor-deposited film. Examples of anchor coat layers include polyurethane-based resins, polyamide-based resins, epoxy-based resins, phenol-based resins, (meth)acrylic-based resins, and polyvinyl acetate-based resins. Examples of polyurethane-based resins include acrylic urethane-based resins and polyester urethane-based resins.

[0038] It is preferable that the substrate 120 of the roll is previously conditioned in humidity during the manufacturing process or humidity conditioning process. This improves the barrier properties. It also prevents substrate breakage during plasma-assisted deposition, which will be described later. One example of humidity conditioning conditions is storage at a temperature of 22 to 30°C and a relative humidity of 40 to 65% RH for 1 to 7 days. Note that rewinding the roll before storage is also effective for humidity conditioning. In this case, it is preferable that the rewinding process is also performed under the humidity conditioning conditions.

[0039] [Vapor-deposited film] Next, the first vapor-deposited film 131b and the second vapor-deposited film 132b (hereinafter, the two films will be simply referred to as vapor-deposited films without distinction) will be described. The vapor-deposited film contains aluminum oxide. In the vapor-deposited film, at least a part of the aluminum is Al ２ O ３ The deposited film may further contain a metal oxide such as silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, magnesium oxide, titanium oxide, tin oxide, indium oxide, zinc oxide, or zirconium oxide, or a nitride or carbide of these metals. The first deposited film 131b and the second deposited film 132b may be the same or different.

[0040] The lower limit of the thickness of the deposited film is preferably 3 nm or more, more preferably 5 nm or more. The upper limit is preferably 100 nm or less, more preferably 50 nm or less, particularly preferably 15 nm or less. The first deposited film 131b and the second deposited film 132b may be the same or different.

[0041] In the present invention, the term "aluminum oxide vapor deposition film" means "a vapor deposition film containing aluminum oxide" as described above, and aluminum oxide Al２ O ３ In addition, aluminum oxide hydroxide AlO(OH) and aluminum hydroxide Al(OH) ３ It may also include the following. This will be explained in detail below.

[0042] (XAFS Spectroscopic Analysis) XAFS analysis is an X-ray Absorption Fine Structure (XAFS) spectrum, in which X-rays are irradiated from the surface side of the vapor-deposited surface of the barrier film (or the coating layer side if there is a coating layer), and the amount of absorbed X-rays is measured. Detailed measurement conditions and analysis conditions are described in the Examples.

[0043] In particular, XAFS spectrum analysis of soft X-rays using synchrotron radiation can provide bulk information on the entire deposited film, rather than just a portion of the surface side of the deposited film, and can provide information on the size of hydroxyl groups in the aluminum oxide deposited film. Even if a coating layer or the like is present on the surface of the deposited film, information on the deposited film in the presence of the coating layer can be obtained by irradiating the deposited film from the surface side of the coating layer through the coating layer. In addition, when a first deposited film 131b and a second deposited film 132b are provided, as in the configuration of Figure 1, a bulk XAFS spectrum can be obtained for the combined state of the two deposited films.

[0044] Fig. 15 shows an example of the results of XAFS measurement of an example of a barrier film in the Examples described later. Fig. 16 shows the peaks obtained by peak separation of the XAFS spectrum in Example 3. In Figs. 15 and 16, the vertical axis represents absorption intensity (a.u.) and the horizontal axis represents energy (eV). The peak top ratio P of the evaporated film in the present invention is the ratio determined from the peak tops of the XAFS spectrum after peak separation, as shown in Fig. 16, for example.

[0045] In the peak separation analysis of Figure 16, "Experiment" is the measured XAFS spectrum, "Fit. Peak 1" is the separated intensity peak at 1566 eV, "Fit. Peak 2" is the separated intensity peak at 1568 eV, and "Fit. Peak 3" is the separated intensity peak at 1572 eV. "Fit. Base 1" is the baseline at 1566 eV, and "Fit. Base 2" is the baseline at 1568 eV.

[0046] 15 and 16, the XAFS spectrum has multiple peaks, specifically, peak P1 with a top near 1566 eV, peak P2 with a top near 1568 eV, and peak P3 with a top near 1572 eV. Note that "near 1566 eV" refers to 1565 eV or more and 1567 eV or less, "near 1568 eV" refers to more than 1567 eV and 1569 eV or less, and "near 1572 eV" refers to 1571 eV or more and 1573 eV or less.

[0047] Here, P1 is considered to be a peak derived from tetracoordinate aluminum oxide, P2 from hexacoordinate aluminum oxide, and P3 from hexacoordinate aluminum hydroxide and aluminum oxide hydroxide.

[0048] Since amorphous aluminum oxide films are thought to have better flexibility than crystalline films, amorphous films are preferred when used as barrier films. However, it has been difficult to determine whether a film is crystalline or amorphous using XRD, a conventional X-ray analysis, except when a clear crystalline peak can be confirmed.

[0049] When XAFS spectra were checked, P1 was detected in the crystalline aluminum oxide film, and γ-Al ２ O ３ and θ-Al ２ O ３ However, the P1 peak is never relatively higher than the P2 peak. According to the examples of the present application described later, it is clear that P1>P2, as in Example 3 (see FIG. 16), and it can be confirmed that an amorphous film is formed.

[0050] Furthermore, it is considered that the aluminum oxide film must be amorphous in order to withstand a brightness maintenance test (described in the Examples below) when used in a wavelength conversion sheet, and that the introduction of hydroxyl groups is necessary. However, for example, in conventional depth analysis using TOF-SIMS, it is unclear whether the aluminum oxide film is being evaluated or whether the moisture remaining at the interface between the aluminum oxide film and the substrate is being detected, and sufficient depth resolution cannot be obtained in the aluminum oxide film when a coating layer is present, and so on, making it impossible to fully investigate the correlation between the film formation conditions and the film quality.

[0051] According to the present invention, by checking the XAFS spectrum and defining the peak top ratio of the deposited film as P = P3 peak top / P1 peak top = (peak top of intensity near 1572 eV) / (peak top of intensity near 1566 eV), it is possible to obtain information about the amount of hydroxyl groups in the aluminum oxide deposited film.

[0052] The present invention has found that the gas barrier property changes depending on the value of the peak top ratio P of the vapor-deposited film. Specifically, by setting the peak top ratio P of the vapor-deposited film to be 0.70 or more and less than 1.05, the luminance maintenance rate can be improved when used in a wavelength conversion sheet. The lower limit of the peak top ratio P of the vapor-deposited film is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.81 or more. The upper limit of the peak top ratio P of the vapor-deposited film is preferably 1.00 or less, more preferably 0.90 or less, and particularly preferably 0.93 or less.

[0053] If the peak top ratio P of the vapor-deposited film is less than 0.70, the introduction of too few hydroxyl groups results in poor film flexibility and reduced gas barrier properties.If the peak top ratio P of the vapor-deposited film is 1.05 or more after a high-temperature, high-humidity wet heat treatment or the like, the introduction of too many hydroxyl groups results in reduced initial barrier properties, particularly water vapor barrier properties.

[0054] In the present invention, the luminance maintenance rate can be made 95% or more in the examples described later. Although the luminance maintenance rate is qualitatively correlated with the barrier property, the test conditions for the luminance maintenance rate are severe conditions in which the film is placed in a constant temperature and humidity chamber at 60°C and 90% RH and left to stand for 1000 hours, and therefore, even if there is no difference in the oxygen and water vapor barrier properties near the measurement limit, there will be a difference in the luminance maintenance rate.

[0055] The peak-top ratio P of the vapor-deposited film in the barrier film can be adjusted by controlling the combination of plasma pretreatment, plasma-assisted treatment during vapor deposition, aging treatment after the film-forming step, and aging treatment after the coating layer-forming step. In particular, by using a combination in which the oxidation of aluminum is promoted by the plasma-assisted treatment during vapor deposition and then the introduction of hydroxyl groups is promoted by the aging treatment after the film-forming step, the luminance maintenance factor can be improved when used in a wavelength conversion sheet. These results are supported by the examples described below.

[0056] (Coating Layer) The first coating layer 131a, which is laminated on the surface of the first aluminum oxide vapor-deposited film 131b, and the second coating layer 132a, which is laminated on the surface of the second aluminum oxide vapor-deposited film 132b, provide mechanical and chemical protection to the aluminum oxide vapor-deposited film and improve the barrier performance of the laminated film having barrier properties. Hereinafter, the first coating layer 131a and the second coating layer 132a (hereinafter, both will be referred to simply as coating layers without distinction) that are coated to form the barrier laminated film will be described. In the following description, the first coating layer 131a and the second coating layer 132a may be the same or different in terms of material, composition, film thickness, etc.

[0057] The coating layer is formed by applying a barrier coating agent onto the aluminum oxide vapor deposition film and then solidifying it. The barrier coating agent is composed of a metal alkoxide, a water-soluble polymer, and optionally a silane coupling agent, a sol-gel catalyst, an acid, etc.

[0058] The metal alkoxides include those represented by the general formula R1 ｎ M (OR ２ ) ｍ (wherein, R１ , R ２ represents an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n+m represents the atomic valence of M. Examples of the metal atom represented by M in the metal alkoxide include silicon, zirconium, titanium, aluminum, and the like. For example, it is preferable to use an alkoxysilane in which M is Si.

[0059] The alkoxysilanes mentioned above include, for example, those represented by the general formula Si(ORa) ４ (wherein, Ra represents a lower alkyl group). In the above, Ra may be a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or the like. Specific examples of the alkoxysilane include tetramethoxysilane Si(OCH ３ ) ４ , tetraethoxysilane Si(OC ２ H ５ ) ４ , tetrapropoxysilane Si(OC ３ H ７ ) 4, tetrabutoxysilane Si(OC ４ H ９ ) ４ Two or more of the above alkoxides may be used in combination.

[0060] As the silane coupling agent, those having a reactive group such as a vinyl group, an epoxy group, a methacryl group, or an amino group can be used. In particular, organoalkoxysilanes having an epoxy group are suitable, and for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropyldimethylmethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyldimethylethoxysilane, or β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane can be used. The above-mentioned silane coupling agents may be used alone or in combination of two or more.

[0061] In particular, the crosslink density of the cured film of a coating layer using bifunctional compounds such as γ-glycidoxypropylmethyldimethoxysilane and γ-glycidoxypropylmethyldiethoxysilane is lower than that of a system using trialkoxysilane. As a result, the cured film has excellent gas barrier properties and hot water treatment resistance, while also being flexible and has excellent flex resistance, so the gas barrier properties of the barrier film are less likely to deteriorate.

[0062] The water-soluble polymer may be a polyvinyl alcohol resin or an ethylene-vinyl alcohol copolymer, either singly or in combination. In the coating layer according to the present embodiment, a polyvinyl alcohol resin is preferred.

[0063] Generally, polyvinyl alcohol resins obtained by saponifying polyvinyl acetate can be used. The polyvinyl alcohol resin may be a partially saponified polyvinyl alcohol resin in which several tens of percent of acetate groups remain, a fully saponified polyvinyl alcohol in which no acetate groups remain, or a modified polyvinyl alcohol resin in which OH groups have been modified. Regarding the degree of saponification of the polyvinyl alcohol resin, it is necessary to use at least one that undergoes crystallization to improve the film hardness of the gas barrier coating film, and preferably has a degree of saponification of 70% or more. Furthermore, any polyvinyl alcohol resin having a degree of polymerization within the range used in conventional sol-gel processes (approximately 100 to 5000) can be used. Examples of such polyvinyl alcohol resins include RS resin "RS-110 (saponification degree = 99%, polymerization degree = 1,000)" manufactured by Kuraray Co., Ltd. and "GOHSENOL NM-14 (saponification degree = 99%, polymerization degree = 1,400)" manufactured by Nippon Synthetic Chemical Industry Co., Ltd.

[0064] The ethylene-vinyl alcohol copolymer may be a saponified copolymer of ethylene and vinyl acetate, i.e., a product obtained by saponifying an ethylene-vinyl acetate random copolymer. For example, it may range from a partially saponified product in which several tens of mole percent of acetate groups remain to a completely saponified product in which only a few mole percent of acetate groups remain, or no acetate groups remain, and is not particularly limited. However, from the viewpoint of barrier properties, the lower limit of the degree of saponification is preferably 80% or more, more preferably 90% or more, and even more preferably 95% or more. The upper limit is 100% or less.

[0065] As the catalyst for the sol-gel method, an acid or amine compound is suitable.

[0066] Examples of acids that can be used include mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid, and organic acids such as acetic acid and tartaric acid.

[0067] The acid content is preferably 0.001 to 0.05 mol %, more preferably 0.01 to 0.03 mol %, based on the total molar amount of alkoxy groups in the metal alkoxide. If the acid content is less than 0.001 mol %, the catalytic effect is too small, whereas if the acid content is more than 0.05 mol %, the catalytic effect is too strong, causing the reaction rate to become too fast and tending to become non-uniform.

[0068] As the amine compound, a tertiary amine that is substantially insoluble in water and soluble in an organic solvent is preferred. Specifically, for example, N,N-dimethylbenzylamine, tripropylamine, tributylamine, tripentylamine, etc. can be used. N,N-dimethylbenzylamine is particularly preferred.

[0069] The content of the amine compound is preferably, for example, 0.01 to 1.0 part by mass, particularly 0.03 to 0.3 part by mass, per 100 parts by mass of the metal alkoxide. If the content is less than 0.01 part by mass, the catalytic effect is too small, whereas if the content is more than 1.0 part by mass, the catalytic effect is too strong, causing the reaction rate to become too fast and tending to become non-uniform.

[0070] As the solvent, it is preferable to use water or alcohol such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropanol, or n-butanol.

[0071] The barrier coating layer formed as described above has a layer thickness of 100 to 500 nm, which is preferable because the coating film does not crack and sufficiently covers the surface of the deposited film.

[0072] The barrier coating agent can be composed of 100 parts by mass of alkoxysilane, 5 to 10 parts by mass of a water-soluble polymer such as a polyvinyl alcohol resin, and 1 to 10 parts by mass of a silane coupling agent. This allows the film to maintain its flexibility. In the above, using more than 20 parts by mass of silane coupling agent increases the rigidity and brittleness of the barrier coating film formed, which is undesirable.

[0073] Furthermore, when a silane coupling agent is not contained, the ratio of the metal alkoxide can be reduced and the barrier property can be improved by using 10 to 20 parts by mass of a water-soluble polymer such as a polyvinyl alcohol resin per 100 parts by mass of alkoxysilane.

[0074] The IO value of the coating layer (the ratio of a metal alkoxide such as tetraethoxysilane (SiO ２ The lower limit of the solid content ratio (based on the % solids content ratio converted into % solids content) is preferably 1.5 or more, more preferably 1.9 or more. The upper limit is preferably 4.5 or less, more preferably 3.5 or less. If it exceeds 4.5, the coating layer loses flexibility and cracks easily occur, which is undesirable because it reduces barrier properties. If it is less than 1.5, the condensation of the hydrolyzate produced from the metal alkoxide does not proceed sufficiently, which is undesirable because it reduces moist heat resistance.

[0075] (C by TOF-SIMS ２ / Si ratio analysis) When the coating layer is etched from the surface of the barrier film opposite to the resin substrate by time-of-flight secondary ion mass spectrometry (TOF-SIMS), the coating layer intensity ratio X, defined as follows, detected in each region of the first coating layer and the second coating layer is 0.50 or more and 1.10 or less. X=C ２ － Ionic strength / Si － Ionic strength

[0076] The coating layer intensity ratio X of the coating layer of the barrier film according to the present embodiment will be described with reference to Example 3 ( FIG. 20 ), which will be described later. FIG. 20 is an example of a graphical analysis diagram showing the detected intensity of secondary ions that reflect the elemental species and chemical structure information when the barrier film of Example 3, which has the layer structure shown in FIG. 1 , is etched (analyzed in the depth direction) from the surface side of the second coating layer 132a (the surface side opposite the substrate) using time-of-flight secondary ion mass spectrometry (TOF-SIMS) to measure the elemental species and chemical structure information contained in the barrier film. The vertical axis of the graph represents the intensity of the detected secondary ions, which is expressed as a common logarithm. The horizontal axis of the graph represents the etching time (seconds) (Et times).

[0077] TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) is a method of mass analysis in which a pulsed primary ion beam is irradiated onto the surface of a solid sample to be analyzed, and secondary ions sputtered and emitted from the sample surface are mass-separated by utilizing the difference in their flight times (the flight time is proportional to the square root of the mass).

[0078] Specifically, when analyzing in the depth direction, the second coating layer 132a and the first coating layer 131a are measured using a time-of-flight secondary ion mass spectrometer while soft etching is repeated at a constant rate from the outermost surface of the second coating layer 132a using a Cs (cesium) ion gun, thereby obtaining graphs of the detection intensities of secondary ions that reflect element species and chemical structure information. As a specific example, as shown in FIG. 20, the ion intensities are ２－ Ion, CN － ions, Si － ions, AlO ２ － ions, SiO ２ － 10 is a graph showing the intensity of detected ions. ２ － Ionic strength and Si － Ion intensity and AlO derived from the second vapor-deposited film 132b ２ － Ion strength and C derived from the first coating layer 131a ２ － Ionic strength and Si － Ion intensity and AlO derived from the first vapor-deposited film 131b ２ － Ionic strength and PET-derived C ２ － The ionic strength is observed in turn.

[0079] In the barrier film of the present invention, the coating layer intensity ratio X, defined as follows, detected in each region of the first coating layer 131a and the second coating layer 132a is 0.50 or more and 1.10 or less. X=C ２ － Ionic strength / Si － Here, the coating layer intensity ratio X is the average value of each coating layer region, and in Figure 20, the calculation was performed assuming that the region of the second coating layer 132a was 500 to 2500 seconds and the region of the first coating layer 131a was 4500 to 6500 seconds, as an example. Note that the detailed measurement conditions for TOF-SIMS are the conditions described in the Examples.

[0080] If the coating layer strength ratio X is less than 0.50, the coating layer loses flexibility and cracks are more likely to occur, which is undesirable as it reduces the barrier properties, and if it exceeds 1.10, the low Si concentration reduces the moist heat resistance, which is undesirable.

[0081] (Film Forming Apparatus) Next, an example of a film forming apparatus 10 used in the manufacturing method of a barrier film will be described. As shown in Fig. 2, the film forming apparatus 10 includes a substrate conveying mechanism 11A for conveying a substrate 1 (corresponding to the substrate 120 described above), a plasma pretreatment mechanism 11B for performing plasma pretreatment on the surface of the substrate 1, and a film forming mechanism 11C for forming a vapor-deposited film. In the example shown in Fig. 5, the film forming apparatus 10 further includes a decompression chamber 12. The decompression chamber 12 has a decompression mechanism, such as a vacuum pump described below, that adjusts the atmosphere in at least a part of the space inside the decompression chamber 12 to atmospheric pressure or below.

[0082] 2, the decompression chamber 12 includes a substrate transport chamber 12A in which the substrate transport mechanism 11A is located, a plasma pretreatment chamber 12B in which the plasma pretreatment mechanism 11B is located, and a film deposition chamber 12C in which the film deposition mechanism 11C is located. The decompression chamber 12 is preferably configured to prevent the atmospheres inside each chamber from mixing with each other. For example, as shown in FIG. 2, the decompression chamber 12 may be located between the substrate transport chamber 12A and the plasma pretreatment chamber 12B, between the plasma pretreatment chamber 12B and the film deposition chamber 12C, and between the substrate transport chamber 12A and the film deposition chamber 12C, and may have partition walls 35a to 35c separating the chambers.

[0083] The substrate transfer chamber 12A, the plasma pretreatment chamber 12B, and the film deposition chamber 12C will now be described. The plasma pretreatment chamber 12B and the film deposition chamber 12C are each provided adjacent to the substrate transfer chamber 12A and each have a portion connecting to the substrate transfer chamber 12A. This allows the substrate to be transferred between the substrate transfer chamber 12A and the plasma pretreatment chamber 12B, and between the substrate transfer chamber 12A and the film deposition chamber 12C without being exposed to the atmosphere. For example, between the substrate transfer chamber 12A and the plasma pretreatment chamber 12B, the substrate 1 can be transferred through an opening provided in the partition wall 35a. The same structure is also provided between the substrate transfer chamber 12A and the film deposition chamber 12C, allowing the substrate to be transferred between the substrate transfer chamber 12A and the film deposition chamber 12C.

[0084] The function of the decompression mechanism of the decompression chamber 12 will now be described. The decompression mechanism of the decompression chamber 12 is configured to be able to decompress the atmosphere in the space in which at least the plasma pretreatment mechanism 11B or the film formation mechanism 11C of the film formation apparatus 10 is disposed to below atmospheric pressure. The decompression mechanism may be configured to be able to decompress the pressure in each of the substrate transfer chamber 12A, the plasma pretreatment chamber 12B, and the film formation chamber 12C, which are partitioned by partition walls 35a to 35c, to below atmospheric pressure.

[0085] The configuration of the decompression mechanism of the decompression chamber 12 will be described. The decompression chamber 12 may have, for example, a vacuum pump connected to the plasma pretreatment chamber 12B. By adjusting the vacuum pump, the pressure inside the plasma pretreatment chamber 12B can be appropriately controlled when performing the plasma pretreatment described below. Furthermore, the method described below can prevent the plasma supplied into the plasma pretreatment chamber 12B from diffusing to other chambers. The decompression mechanism of the decompression chamber 12 may have a vacuum pump connected to the film formation chamber 12C, similar to the vacuum pump connected to the plasma pretreatment chamber 12B. The vacuum pump may be a dry pump, a turbomolecular pump, a cryopump, a rotary pump, a diffusion pump, or the like.

[0086] A substrate transport mechanism 11A for the substrate 1 of the film formation apparatus 10 according to this embodiment will be described together with the transport path of the substrate 1. The substrate transport mechanism 11A is a mechanism for transporting the substrate 1, disposed in the substrate transport chamber 12A. In the example shown in FIG. 2, the substrate transport mechanism 11A includes an unwinding roller 13 to which a roll of the substrate 1 is attached, a take-up roller 15 that winds up the substrate 1, and guide rolls 14a to 14d. The substrate 1 sent out from the substrate transport mechanism 11A is then transported by a pretreatment roller 20 (described later) disposed in the plasma pretreatment chamber 12B and a film formation roller 25 (described later) disposed in the film formation chamber 12C.

[0087] Although not shown, the substrate conveying mechanism 11A may further include a tension pickup roller. By including the tension pickup roller in the substrate conveying mechanism 11A, the substrate 1 can be conveyed while adjusting the tension applied to the substrate 1.

[0088] (Plasma Pretreatment Mechanism) The plasma pretreatment mechanism 11B will be described. The plasma pretreatment mechanism 11B is a mechanism for performing plasma pretreatment on the surface of the substrate 1. The plasma pretreatment mechanism 11B shown in FIG. 2 generates plasma P and performs plasma pretreatment on the surface of the substrate 1 using the generated plasma P. When the surface of the substrate 1 is activated by plasma pretreatment, for example, hydrogen is released from the substrate resin component to generate carbon radicals. These radicals then bond with oxygen and hydrogen in the atmosphere to generate functional groups such as hydroxyl groups, carboxyl groups, and ketone groups. The generation of such functional groups is thought to improve the adhesion between the substrate 1 and the vapor-deposited film. The plasma pretreatment mechanism 11B shown in FIG. 2 includes a pretreatment roller 20 arranged in a plasma pretreatment chamber 12B, an electrode unit 21 facing the pretreatment roller 20, and a magnetic field generating unit 23 that generates a magnetic field between the pretreatment roller 20 and the electrode unit 21.

[0089] The pretreatment roller 20 will now be described. FIG. 3 is an enlarged view of the area surrounded by the dashed line marked with the symbol VI in FIG. 2. Note that FIG. 3 omits the power supply wiring 31 connecting the power source 32 shown in FIG. 2 to the electrode unit 21 described later, and the plasma P generated by the plasma pretreatment mechanism 11B. The pretreatment roller 20 has a rotation axis X. The pretreatment roller 20 is arranged so that at least the rotation axis X is located within the plasma pretreatment chamber 12B, which is partitioned by partition walls 35a and 35b. A substrate 1 having a dimension in the direction of the rotation axis X is wrapped around the pretreatment roller 20. In the following description, the dimension of the substrate 1 in the direction of the rotation axis X is also referred to as the width of the substrate 1. The direction of the rotation axis X is also referred to as the width direction of the substrate 1.

[0090] As shown in Fig. 2, the pretreatment roller 20 may be provided so that a portion thereof is exposed on the substrate transport chamber 12A side. In the example shown in Fig. 2, the plasma pretreatment chamber 12B and the substrate transport chamber 12A are connected via an opening provided in the partition wall 35a, and a portion of the pretreatment roller 20 is exposed on the substrate transport chamber 12A side through this opening. A gap is provided between the partition wall 35a between the substrate transport chamber 12A and the plasma pretreatment chamber 12B and the pretreatment roller 20, and the substrate 1 can be transported from the substrate transport chamber 12A to the plasma pretreatment chamber 12B through this gap. Although not shown, the pretreatment roller 20 may be provided so that its entirety is located within the plasma pretreatment chamber 12B.

[0091] Although not shown, the pretreatment roller 20 may have a temperature adjustment mechanism that adjusts the temperature of the surface of the pretreatment roller 20. For example, the pretreatment roller 20 may have a temperature adjustment mechanism inside the pretreatment roller 20 that includes piping for circulating a temperature adjustment medium such as a refrigerant or a heat medium. The temperature adjustment mechanism adjusts the surface temperature of the pretreatment roller 20 to a target temperature within a range of, for example, −20° C. or higher and 100° C. or lower.

[0092] By providing the pretreatment roller 20 with a temperature adjustment mechanism, shrinkage or damage to the substrate 1 due to heat during plasma pretreatment can be suppressed.

[0093] The pretreatment roller 20 is formed from a material containing at least one of stainless steel, iron, copper, and chromium. The surface of the pretreatment roller 20 may be treated with a hard chromium hard coat to prevent scratches. These materials are easy to process. Furthermore, using the above materials for the pretreatment roller 20 increases the thermal conductivity of the pretreatment roller 20 itself, making it easier to control the temperature of the pretreatment roller 20.

[0094] The electrode unit 21 will now be described. In the example shown in FIGS. 2 and 3, the electrode unit 21 has a first surface 21c facing the pretreatment roller 20 and a second surface 21d located on the opposite side of the first surface 21c. In the example shown in FIGS. 2 and 3, the electrode unit 21 is a plate-shaped member, and both the first surface 21c and the second surface 21d are flat. The electrode unit 21 generates plasma between itself and the pretreatment roller 20 by applying an AC voltage between itself and the pretreatment roller 20. The electrode unit 21 preferably forms an electric field between itself and the pretreatment roller 20 such that the generated plasma moves perpendicular to the surface of the substrate 1 and toward the surface of the substrate 1. This allows the substrate 1 to be pretreated efficiently.

[0095] The number of electrode units 21 is preferably two or more. The two or more electrode units 21 are preferably arranged along the transport direction of the substrate 1. In the examples shown in Figures 2 and 3, the film forming apparatus 10 has two electrode units 21. The number of electrode units 21 is, for example, 12 or less.

[0096] The effect of two or more electrode units 21 arranged along the transport direction of the substrate 1 will be described. As described above, plasma is generated between the electrode unit 21 and the pretreatment roller 20. The area in which plasma is generated expands as the dimension of the electrode unit 21 in the transport direction increases. On the other hand, when the electrode unit 21 is a flat, plate-shaped member, the larger the dimension of the electrode unit 21 in the transport direction, the greater the distance from the end of the first surface 21c of the electrode unit 21, which is the surface facing the pretreatment roller 20, to the pretreatment roller 20 in the transport direction, which reduces the processing ability of the plasma.

[0097] In the film forming apparatus 10, two or more electrode units 21 are arranged along the transport direction of the substrate 1. Therefore, even if the dimensions of the electrode units 21 in the transport direction of the substrate 1 are small, plasma can be generated over a wide range in the transport direction. Furthermore, by reducing the dimensions of the electrode units 21, the distance from the end of the first surface 21c of the electrode units 21 to the pretreatment roller 20 in the transport direction can be reduced, and plasma can be generated uniformly in the transport direction.

[0098] As shown in FIGS. 2 and 3 , the electrode unit 21 has a first end 21e and a second end 21f located on the first surface 21c of the electrode unit 21. The first end 21e is the upstream end in the transport direction of the substrate 1, and the second end 21f is the downstream end in the transport direction of the substrate 1. As described above, by reducing the dimension of the electrode unit 21 in the transport direction of the substrate 1, the distance from the first end 21e and the second end 21f of the electrode unit 21 to the pretreatment roller 20 in the transport direction can be reduced. The dimension of the electrode unit 21 in the transport direction of the substrate 1 corresponds to the angle θ shown in FIG. 3 . The angle θ is the angle formed between a line passing through the first end 21e and the rotation axis X and a line passing through the second end 21f and the rotation axis X. The angle θ is preferably 20° or more and 90° or less, more preferably 60° or less, and even more preferably 45° or less. By setting the angle θ within the above range, plasma can be generated uniformly in the transport direction between the electrode unit 21 and the pretreatment roller 20 when the first surface 21c of the electrode unit 21 is flat.

[0099] There are no particular limitations on the material of the electrode portion 21 as long as it is conductive. Specifically, aluminum, copper, and stainless steel are preferably used as the material of the electrode portion 21.

[0100] The thickness L3 of the electrode unit 21 when viewed in a direction perpendicular to the first surface 21c of the electrode unit 21 is not particularly limited, but is, for example, 15 mm or less. When the thickness of the electrode unit 21 is the above value, the magnetic field generating unit 23 can effectively generate a magnetic field between the pretreatment roller 20 and the electrode unit 21. Furthermore, the thickness L3 of the electrode unit 21 is, for example, 3 mm or more.

[0101] The magnetic field forming unit 23 will now be described. As shown in FIGS. 2 and 3 , the magnetic field forming unit 23 is provided on the side of the electrode unit 21 opposite the side facing the pretreatment roller 20. The magnetic field forming unit 23 is a member that forms a magnetic field between the pretreatment roller 20 and the electrode unit 21. The magnetic field between the pretreatment roller 20 and the electrode unit 21 contributes to the generation of higher density plasma, for example, when plasma is generated using the plasma pretreatment mechanism 11B. The magnetic field forming unit 23 shown in FIGS. 2 and 3 has a first magnet 231 and a second magnet 232 provided on the second surface 21 d of the electrode unit 21.

[0102] The number of magnetic field forming units 23 is preferably 2 or more. When the plasma pretreatment mechanism 11B has two or more electrode units 21 and two or more magnetic field forming units 23, each of the two or more magnetic field forming units 23 is preferably provided on the side of each of the two or more electrode units 21 opposite the side facing the pretreatment roller 20. In the example shown in Figures 2 and 3, each of the two magnetic field forming units 23 is provided on the second surface 21d of each of the two electrode units 21.

[0103] The structure of the first magnet 231 and the second magnet 232 in the normal direction of the second surface 21d of the electrode unit 21 will be described. As shown in FIGS. 2 and 3, the first magnet 231 and the second magnet 232 each have a north pole and a south pole. The symbol N in FIGS. 2 and 3 indicates the north pole of the first magnet 231 or the second magnet 232. The symbol S in FIGS. 2 and 3 indicates the south pole of the first magnet 231 or the second magnet 232. One of the north pole or south pole of the first magnet 231 is located closer to the substrate 1 than the other. The other of the north pole or south pole of the second magnet 232 is located closer to the substrate 1 than the other. In the example shown in FIGS. 2 and 3, the north pole of the first magnet 231 is located closer to the substrate 1 than the south pole of the first magnet 231, and the south pole of the second magnet 232 is located closer to the substrate 1 than the north pole of the second magnet. Although not shown in the figure, the south pole of the first magnet 231 may be located closer to the substrate 1 than the north pole of the first magnet 231, and the north pole of the second magnet 232 may be located closer to the substrate 1 than the south pole of the second magnet 232.

[0104] Next, the structure of the first magnet 231 and the second magnet 232 in the planar direction of the second surface 21d of the electrode unit 21 will be described. Fig. 4 is a plan view of the electrode unit 21 and magnetic field generating unit 23 shown in Fig. 2, viewed from the magnetic field generating unit 23 side. Fig. 5 is a cross-sectional view showing a cross section taken along line VIII-VIII in Fig. 4. In Fig. 4, direction D1 is the direction in which the rotation axis X of the pre-treatment roller 20 extends.

[0105] As shown in Figures 4 and 5, the first magnet 231 has a first axial portion 231c. As shown in Figure 4, the first axial portion 231c extends along direction D1, i.e., along the rotation axis X of the pre-treatment roller 20. The first magnet 231 provided on one electrode unit 21 may have one first axial portion 231c, or may have two or more first axial portions 231c. In the example shown in Figure 4, the first magnet 231 provided on one electrode unit 21 has one first axial portion 231c.

[0106] 4 and 5, the second magnet 232 has a second axial portion 232c. As shown in Fig. 4, the second axial portion 232c also extends along the direction D1, i.e., along the rotation axis X, similar to the first axial portion 231c.

[0107] Since both the first magnet 231 and the second magnet 232 include a portion extending along the rotation axis X, it is possible to increase the uniformity in the width direction of the substrate 1 of the strength of the magnetic field formed around the substrate 1. This makes it possible to increase the uniformity in the width direction of the substrate 1 of the distribution density of the plasma formed around the substrate 1.

[0108] The second magnet 232 provided on one electrode unit 21 may have one second axial portion 232c or two or more second axial portions 232c. In the example shown in Figures 4 and 5, the second magnet 232 provided on one electrode unit 21 has two second axial portions 232c. The two second axial portions 232c may be positioned so as to sandwich the first axial portion 231c in the direction D2 perpendicular to the rotation axis X in the planar direction of the second surface 21d of the electrode unit 21.

[0109] 5, the dimension L4 of the first axial portion 231c and the dimension L5 of the second axial portion 232c in the conveyance direction of the substrate 1 are not particularly limited. Furthermore, the ratio between the dimension L4 of the first axial portion 231c and the dimension L5 of the second axial portion 232c in the conveyance direction of the substrate 1 is not particularly limited. The dimension L4 of the first axial portion 231c and the dimension L5 of the second axial portion 232c may be equal, or the dimension L4 of the first axial portion 231c may be larger than the dimension L5 of the second axial portion 232c.

[0110] The distance L6 between the first axial portion 231c and the second axial portion 232c in the direction D2 is set so that a magnetic field generated by the first axial portion 231c and the second axial portion 232c is formed between the pre-treatment roller 20 and the electrode portion 21.

[0111] The second magnet 232 may surround the first magnet 231 when the magnetic field generating unit 23 is viewed along the normal direction of the second surface 21d of the electrode unit 21. For example, as shown in Fig. 4, the second magnet 232 may have two second axial portions 232c and two connecting portions 232d provided to connect the two second axial portions 232c.

[0112] Examples of the types of magnets used as the magnetic field generating unit 23, such as the first magnet 231 and the second magnet 232, include permanent magnets such as ferrite magnets and rare earth magnets such as neodymium and samarium cobalt (samarium-cobalt). Alternatively, an electromagnet can be used as the magnetic field generating unit 23.

[0113] The magnetic flux density of the magnets of the magnetic field generating unit 23, such as the first magnet 231 and the second magnet 232, is, for example, 100 Gauss or more and 10,000 Gauss or less. If the magnetic flux density is 100 Gauss or more, a sufficiently strong magnetic field is formed between the pretreatment roller 20 and the electrode unit 21, thereby generating a sufficiently high-density plasma and enabling a good pretreatment surface to be formed at high speed. On the other hand, to increase the magnetic flux density on the surface of the substrate 1 to more than 10,000 Gauss, an expensive magnet or magnetic field generating mechanism is required.

[0114] Although not shown, the plasma pretreatment mechanism 11B may have a plasma raw material gas supply unit. The plasma raw material gas supply unit supplies a plasma raw material gas into the plasma pretreatment chamber 12B. The configuration of the plasma raw material gas supply unit is not particularly limited. For example, the plasma raw material gas supply unit may be provided on the wall surface of the plasma pretreatment chamber 12B and include a hole for ejecting the plasma raw material gas. The plasma raw material gas supply unit may also have a nozzle for ejecting the plasma raw material gas at a position closer to the substrate 1 than the wall surface of the plasma pretreatment chamber 12B. The plasma raw material gas supplied by the plasma raw material gas supply unit may be, for example, an inert gas such as argon, an active gas such as oxygen, nitrogen, carbon dioxide, or ethylene, or a mixture of these gases. As the plasma raw material gas, a single inert gas, a single active gas, or a mixture of two or more gases contained in the inert gas or active gas may be used. As the plasma raw material gas, a mixture of an inert gas such as argon and an active gas may be used. As an example, the plasma raw material gas supply unit may be a gas supplying unit that supplies argon (Ar) and oxygen (O ２ ) mixed gas is supplied.

[0115] The plasma pretreatment mechanism 11B has a plasma density of, for example, 100 W·sec / m ２ More than 8000W・sec / m ２ The following plasma is supplied between the pretreatment roller 20 and the electrode unit 21.

[0116] 2, the plasma pretreatment mechanism 11B is disposed in a plasma pretreatment chamber 12B, which is separated by a partition wall from the substrate transport chamber 12A and the film formation chamber 12C. By separating the plasma pretreatment chamber 12B from other areas, such as the substrate transport chamber 12A and the film formation chamber 12C, it becomes easier to adjust the atmosphere in the plasma pretreatment chamber 12B independently. This makes it easier to control the plasma raw material gas concentration in the space where the pretreatment roller 20 and the electrode unit 21 face each other, improving the productivity of laminated films.

[0117] (Film Forming Mechanism) Next, the film forming mechanism 11C will be described. In the example shown in Fig. 2, the film forming mechanism 11C has a film forming roller 25 and an evaporation mechanism 24 disposed in the film forming chamber 12C.

[0118] The film-forming roller 25 will be described. The film-forming roller 25 is a roller that wraps around and transports the substrate 1 with the treated surface of the substrate 1 that has been pretreated in the plasma pretreatment mechanism 11B facing outward.

[0119] The material of the film-forming roller 25 will now be described. The film-forming roller 25 is preferably formed from a material containing at least one of stainless steel, iron, copper, and chromium. The surface of the film-forming roller 25 may be treated with a hard chromium hard coat to prevent scratches. These materials are easy to process. Furthermore, by using the above-mentioned materials for the film-forming roller 25, the thermal conductivity of the film-forming roller 25 itself is increased, resulting in excellent temperature controllability during temperature control. The average surface roughness Ra of the surface of the film-forming roller 25 is, for example, 0.1 μm or more and 10 μm or less.

[0120] Although not shown, the film-forming roller 25 may also have a temperature adjustment mechanism for adjusting the surface temperature of the film-forming roller 25. The temperature adjustment mechanism may, for example, have a circulation path for circulating a cooling medium or a heat source medium inside the film-forming roller 25. The cooling medium (refrigerant) may be, for example, an ethylene glycol aqueous solution, and the heat source medium (heat medium) may be, for example, silicone oil. The temperature adjustment mechanism may also have a heater installed in a position opposite the film-forming roller 25. When the film-forming mechanism 11C forms a film by vapor deposition, in consideration of the heat resistance constraints of related mechanical components and versatility, the temperature adjustment mechanism preferably adjusts the surface temperature of the film-forming roller 25 to a target temperature within a range of -20°C to 200°C. By having the film-forming roller 25 have a temperature adjustment mechanism, fluctuations in the temperature of the substrate 1 due to heat generated during film formation can be suppressed.

[0121] The evaporation mechanism 24 will now be described. FIG. 6 is an enlarged view of the area enclosed by the dashed line designated by the symbol IX in FIG. 2 , showing a specific configuration of the evaporation mechanism 24 (omitted in FIG. 5 ) and a diagram showing the evaporation material supply unit 61 (omitted in FIG. 2 ) for supplying the evaporation material. Note that the decompression chamber 12 and partition walls 35b and 35c are omitted from FIG. 6 . The evaporation mechanism 24 evaporates the evaporation material containing aluminum. The evaporated evaporation material adheres to the substrate 1, thereby forming an aluminum-containing evaporation film on the surface of the substrate 1. The evaporation mechanism 24 in this embodiment employs a resistance heating system. In the example shown in FIG. 6 , the evaporation mechanism 24 includes a boat 24b. In this embodiment, the boat 24b includes a power supply (not shown) and a resistor (not shown) electrically connected to the power supply. A plurality of boats 24b may be arranged in the width direction of the substrate 1.

[0122] 6, the film forming mechanism 11C may have a vapor deposition material supply unit 61 that supplies a vapor deposition material to the evaporation mechanism 24. In FIG. 6, an example is shown in which the vapor deposition material supply unit 61 continuously feeds out an aluminum metal wire.

[0123] Although not shown, the film formation mechanism 11C has a gas supply mechanism. The gas supply mechanism is a mechanism that supplies gas between the evaporation mechanism 24 and the film formation roller 25. The gas supply mechanism supplies at least oxygen gas. The oxygen gas reacts with or bonds with an evaporation material such as aluminum that evaporates from the evaporation mechanism 24 and heads toward the substrate 1 on the film formation roller 25. This allows a vapor deposition film containing aluminum oxide to be formed on the surface of the substrate 1.

[0124] The film formation mechanism 11C also includes a plasma supply mechanism 50 that supplies plasma between the surface of the substrate 1 and the evaporation mechanism 24. In the examples shown in FIGS. 2 and 6 , the plasma supply mechanism 50 has a hollow cathode 51. In this embodiment, the hollow cathode 51 is a cathode having a hollow portion that is partially open. The hollow cathode 51 can generate plasma within the hollow portion. In the example shown in FIG. 6 , the hollow cathode 51 is disposed so that the opening of the hollow portion of the hollow cathode 51 is positioned diagonally above the boat 24b. Although not shown, the plasma supply mechanism 50 according to this embodiment also includes an anode facing the opening, which extracts plasma from the opening of the hollow cathode 51. The plasma supply mechanism 50 according to this embodiment generates plasma within the hollow portion of the hollow cathode 51 and extracts the plasma between the surface of the substrate 1 and the evaporation mechanism 24 using the opposing anode, thereby generating a strong plasma between the surface of the substrate 1 and the evaporation mechanism 24. The position of the opposing anodes is not particularly limited as long as the opposing anodes can extract plasma from the opening of the cavity of the hollow cathode 51 and supply plasma between the surface of the substrate 1 and the evaporation mechanism 24. In this embodiment, a case will be described in which the opposing anodes are arranged on both sides of the boat 24b in the width direction of the substrate 1. In this case, the film formation mechanism 11C has a plurality of boats 24b and a plurality of opposing anodes, and the plurality of boats 24b and the plurality of opposing anodes may be arranged alternately in the width direction of the substrate 1. Although not shown, the plasma supply mechanism 50 may have a raw material supply device that supplies a plasma raw material gas at least into the cavity of the hollow cathode 51. The plasma raw material gas supplied by the raw material supply device may be, for example, the same gas as the plasma raw material gas supplied by the plasma raw material gas supply unit of the plasma pretreatment mechanism 11B.

[0125] By using the plasma supply mechanism 50 to supply plasma between the surface of the substrate 1 and the evaporation mechanism 24, plasma assist during deposition can be performed, activating the aluminum and oxygen gas evaporated in the evaporation mechanism 24 and promoting the reaction or bonding of the aluminum and oxygen gas. This can increase the proportion of aluminum present as aluminum oxide in the evaporated film formed on the surface of the substrate 1, and stabilize the properties of the evaporated film.

[0126] Although not shown, the film forming apparatus 10 may include a substrate charge removal unit in the substrate transport chamber 12A, located downstream of the film formation chamber 12C in the transport direction of the substrate 1. The substrate charge removal unit performs post-processing to remove charge generated on the substrate 1 due to film formation by the film formation mechanism 11C. The substrate charge removal unit may be provided to remove charge from one side of the substrate 1, or may be provided to remove charge from both sides of the substrate 1.

[0127] The device used as the substrate charge removal unit for performing post-treatment on the substrate 1 is not particularly limited, but examples thereof include a plasma discharge device, an electron beam irradiation device, an ultraviolet irradiation device, a static elimination bar, a glow discharge device, and a corona treatment device.

[0128] When post-treatment is performed by forming a discharge using a plasma treatment device or a glow discharge device, a discharge gas such as argon, oxygen, nitrogen, or helium, or a mixture of these, is supplied near the substrate 1, and post-treatment can be performed using any discharge method such as alternating current (AC) plasma, direct current (DC) plasma, arc discharge, microwave, or surface wave plasma. In a reduced pressure environment, it is most preferable to perform post-treatment using a plasma discharge device.

[0129] The substrate charge removal unit is installed in a portion of the substrate transport chamber 12A that is located downstream of the film-forming chamber 12C in the transport direction of the substrate 1, and by removing the charge from the substrate 1, the substrate 1 can be transported by quickly separating it from the film-forming roller 25 at a predetermined position. This enables stable substrate transport, prevents damage to the substrate 1 or deterioration in quality due to charging, and improves post-processing suitability by improving the wettability of the front and back surfaces of the substrate.

[0130] (Power Supply) In the example shown in FIG. 2 , the film forming apparatus 10 further includes a power supply 32 electrically connected to the pretreatment roller 20 and the electrode unit 21. In the example shown in FIG. 5 , the power supply 32 is electrically connected to the pretreatment roller 20 and the electrode unit 21 via power supply wiring 31. The power supply 32 is, for example, an AC power supply. When the power supply 32 is an AC power supply, the power supply 32 can apply an AC voltage having a frequency of, for example, 20 kHz to 500 kHz between the pretreatment roller 20 and the electrode unit 21. The input power that can be applied by the power supply 32 (the power that can be applied per 1 m width of the electrode unit 21 in the width direction of the substrate 1) is not particularly limited, but is, for example, 0.5 kW / m to 20 kW / m. The pretreatment roller 20 may be installed at an electrically earth level or at an electrically floating level.

[0131] (Method for manufacturing a barrier film) Next, a method for manufacturing the barrier film shown in FIG. 1 using the above-described film formation apparatus 10 will be described. First, a first film formation step (hereinafter also simply referred to as the film formation step) of forming a first vapor-deposited film on the surface of the substrate 1 will be described. In film formation using the film formation apparatus 10, a plasma pretreatment step of performing plasma pretreatment on the surface of the substrate 1 using the plasma pretreatment mechanism 11B and a film formation step of forming a vapor-deposited film on the surface of the substrate 1 using the film formation mechanism 11C are performed while the substrate 1 is transported along the above-described transport path of the substrate 1. The transport speed of the substrate 1 is preferably 200 m / min or more, and more preferably 400 m / min or more and 1000 m / min or less.

[0132] (Plasma Pretreatment Step) The plasma pretreatment step is performed, for example, by the following method. First, a plasma raw material gas is supplied into the plasma pretreatment chamber 12B. Next, the above-mentioned AC voltage is applied between the pretreatment roller 20 and the electrode unit 21. When applying the AC voltage, input power control, impedance control, or the like may be performed.

[0133] The plasma raw material gas supplied in the pretreatment is oxygen alone or a mixture of oxygen gas and an inert gas, which is supplied from a gas reservoir through a flow rate controller while the flow rate of the gas is measured. The inert gas may be one or a mixture of two or more gases selected from the group consisting of argon, helium, and nitrogen.

[0134] In the plasma treatment, the mixing ratio of oxygen gas to the inert gas, that is, oxygen gas / inert gas, is preferably 6 / 1 to 1 / 1, and more preferably 5 / 2 to 3 / 2.5.

[0135] By setting the mixing ratio to 6 / 1 to 1 / 1, the film formation energy of the vapor-deposited aluminum on the resin substrate increases, and by setting the ratio to 5 / 2 to 3 / 2, the degree of oxidation of the aluminum oxide vapor-deposited film is increased, thereby ensuring adhesion between the aluminum oxide vapor-deposited film and the substrate 1.

[0136] Application of AC voltage generates plasma simultaneously with glow discharge, and plasma P becomes denser between pretreatment roller 20 and magnetic field forming unit 23. In this way, plasma P can be supplied between pretreatment roller 20 and magnetic field forming unit 23. This plasma P can be used to perform plasma (ion) pretreatment on the surface of substrate 1.

[0137] Plasma intensity per unit area in plasma processing: 50 W·sec / m ２ More than 8000W・sec / m ２ less than 50 W·sec / m ２ Below this, the effect of plasma pretreatment is not observed, and ２ Above this level, the resin substrate tends to be deteriorated by the plasma, such as worn, damaged, discolored, and burned. In particular, the plasma intensity for plasma pretreatment to form an aluminum oxide layer should be 100 W·sec / m ２ More than 1000W・sec / m ２ The following is preferred:

[0138] The pressure inside plasma pretreatment chamber 12B when an AC voltage is applied between pretreatment roller 20 and electrode unit 21 is reduced to below atmospheric pressure by decompression chamber 12. In this case, the pressure inside plasma pretreatment chamber 12B is adjusted, for example, so that the application of AC voltage can cause a glow discharge between pretreatment roller 20 and electrode unit 21. The pressure inside plasma pretreatment chamber 12B when an AC voltage is applied between pretreatment roller 20 and electrode unit 21 can be set and maintained at approximately 0.1 Pa or more and 100 Pa or less, and a pressure of 1 Pa or more and 20 Pa or less is particularly preferred.

[0139] The function of the magnetic field generating unit 23 in the plasma pretreatment step will now be described. The magnetic field generating unit 23 generates a magnetic field between the pretreatment roller 20 and the electrode unit 21. The magnetic field can act to capture and accelerate electrons present between the pretreatment roller 20 and the electrode unit 21. This increases the frequency of collisions between electrons and the plasma raw material gas in the region where the magnetic field is generated, thereby increasing and localizing the plasma density and improving the efficiency of the plasma pretreatment.

[0140] (First Film Forming Step) In the film forming step, a film is formed on the surface of the substrate 1 using the film forming mechanism 11C. As an example of the film forming step, a case will be described in which an aluminum oxide vapor deposition film is formed using the film forming mechanism 11C having the evaporation mechanism 24 shown in FIG.

[0141] First, an evaporation material containing aluminum is supplied into the boat 24b of the evaporation mechanism 24 so as to face the deposition roller 25. An aluminum metal wire rod can be used as the evaporation material. In the example shown in FIG. 6 , the evaporation material is supplied to the boat 24b by continuously feeding the aluminum metal wire rod into the boat 24b using an evaporation material supply unit 61.

[0142] The aluminum is evaporated in the boat 24b by heating. For convenience, FIG. 6 illustrates evaporated aluminum vapor 63. The oxygen gas that oxidizes the aluminum may be supplied as oxygen alone or as a mixed gas with an inert gas such as argon. By controlling the amount of oxygen, both barrier properties and transparency can be achieved. The pressure at this time is preferably 0.05 Pa or more and 8.00 Pa or less.

[0143] Next, a method for supplying plasma between the surface of the substrate 1 and the evaporation mechanism 24 by the plasma supply mechanism 50, i.e., plasma assistance during deposition, will be described. In this embodiment, plasma is generated within the cavity of the hollow cathode 51 of the plasma supply mechanism 50. Next, a discharge is generated between the hollow cathode 51 and the opposing anode, and the plasma within the cavity of the hollow cathode 51 is drawn between the surface of the substrate 1 and the evaporation mechanism 24.

[0144] In this embodiment, the discharge generated between the hollow cathode 51 and the opposing anode is an arc discharge, which means a discharge with a current value of 10 A or more, for example.

[0145] By evaporating aluminum while supplying plasma between the surface of the substrate 1 and the evaporation mechanism 24, the plasma is supplied to the aluminum vapor 63. The supply of plasma can promote the reaction or bonding of the aluminum vapor 63 with oxygen gas. This allows the aluminum vapor 63 to be oxidized before it reaches the surface of the substrate 1. The evaporated and oxidized aluminum adheres to the substrate 1, forming an aluminum oxide vapor deposition film on the surface of the substrate 1, and the barrier film shown in FIG. 1 can be produced.

[0146] The plasma raw material gas supplied by the plasma supply mechanism 50 is preferably argon gas.

[0147] In this embodiment, a plasma pretreatment step is performed before the film formation step, in which plasma is supplied to the surface of the substrate 1. In the plasma pretreatment step, an AC voltage is applied between the electrode unit 21 and the pretreatment roller 20. Furthermore, a magnetic field is generated in the space between the electrode unit 21 and the pretreatment roller 20 by utilizing the magnetic field generating unit 23 located on the surface of the electrode unit 21 opposite the surface facing the pretreatment roller 20. This allows plasma to be efficiently generated in the space between the electrode unit 21 and the pretreatment roller 20, and allows the plasma to be incident perpendicularly on the surface of the substrate 1 wrapped around the pretreatment roller 20. This therefore improves adhesion between the film formed in the film formation step and the substrate 1.

[0148] (Aging Treatment After Film Formation Step) The wound barrier film that has undergone the above-described film formation step is subjected to an aging treatment (heating treatment) for a predetermined period of time, which promotes the introduction of hydroxyl groups into the vapor-deposited aluminum oxide film, thereby forming a vapor-deposited film with excellent barrier properties, particularly excellent water vapor barrier properties.

[0149] The aging temperature is preferably 50°C or higher and 60°C or lower. The lower limit of the aging time is 24 hours (1 day) or higher, more preferably 48 hours (2 days) or higher. The upper limit is 144 hours (6 days) or lower, more preferably 96 hours (4 days) or lower. The aging humidity is not particularly limited, but does not need to be high, and a normal relative humidity of 40% or higher and 70% or lower is sufficient.

[0150] (First Coating Layer Formation Step) In the first coating layer formation step (hereinafter simply referred to as the coating layer formation step), the first coating layer can be produced by the following method. First, a barrier coating agent is prepared by mixing the metal alkoxide, a water-soluble polymer, a silane coupling agent (if necessary), a sol-gel catalyst, an acid, and an organic solvent such as water or an alcohol (e.g., methyl alcohol, ethyl alcohol, isopropanol, etc.) as a solvent. Next, the barrier coating agent is applied to the aluminum oxide vapor-deposited film by a conventional method and dried. This drying step further promotes polycondensation of silanols generated from the metal alkoxide and silane coupling agent, forming a coating film. The drying conditions include a heat treatment at a temperature of 20 to 200°C and below the melting point of the plastic substrate 1, preferably in the range of 50 to 180°C, for 3 seconds to 10 minutes. This allows a coating layer of the barrier coating agent to be formed on the aluminum oxide vapor-deposited film. The above coating operation may be further repeated on the first coating film to form multiple coating films consisting of two or more layers.

[0151] The barrier film roll that has undergone the coating layer formation step is then subjected to an aging treatment (heating treatment) for a predetermined period of time, which allows the condensation of the coating layer to proceed appropriately, resulting in a barrier film whose barrier properties are less likely to deteriorate.

[0152] The lower limit of the aging temperature after the coating layer formation step is preferably 40°C or higher, more preferably 50°C or higher. The upper limit is preferably 100°C or lower, more preferably 70°C or lower. The lower limit of the aging time is 24 hours (1 day) or higher, more preferably 48 hours (2 days) or higher. The upper limit is 144 hours (6 days) or lower, more preferably 96 hours (4 days) or lower. The aging humidity is not particularly limited, but does not need to be high, and a normal relative humidity of 40% or higher and 70% or lower is sufficient.

[0153] (Second film formation process) An aluminum oxide vapor deposition film is further formed on the first coating layer to form the second vapor deposition film 132b in Figure 1. This film can be formed under the same conditions as the plasma pretreatment process, the first film formation process, and the aging treatment described above. The first vapor deposition film and the second vapor deposition film may be formed under the same conditions or under different conditions.

[0154] (Second coating layer forming process) Furthermore, the second coating layer 132a in Fig. 1 is formed on the aluminum oxide vapor-deposited film vapor-deposited through the second film-forming process. The film formation can be performed under the same conditions as the first coating layer forming process. The first coating layer and the second coating layer may be formed under the same conditions or different conditions.

[0155] <<Laminate>> Next, a laminate of the present invention using a barrier film will be described. The laminate 100B in Fig. 7 is an example showing a laminate using the barrier film of Fig. 1. Compared to the barrier film 100A in Fig. 1, a matte layer 160 is formed on the surface of the substrate 120 opposite to the first vapor-deposited film 131b. The laminate of the present invention is suitable for use in wavelength conversion sheets, etc.

[0156] 8, the substrate 120 of the barrier film 100A and the support 150 are laminated together via a pressure-sensitive adhesive layer or adhesive layer 140 (hereinafter referred to as the tacky-adhesive layer 140). The matte layer 160 is formed on the surface of the support 150 opposite to the barrier film 100A.

[0157] 9, the barrier layer 130 of the barrier film 100A and the support 150 are laminated together via a pressure-sensitive adhesive layer or adhesive layer 140 (hereinafter referred to as the adhesive layer 140). That is, the laminate 100D differs from that of FIG. 8 in that the barrier film 100A is disposed in the reverse direction.

[0158] In this way, the matte layer 160 may be formed on the surface of the substrate 120 opposite to the first aluminum oxide vapor-deposited film 131b. Specifically, the matte layer 160 may be formed on one surface of the substrate 120. In this case, this includes not only the case where the matte layer is formed directly on the surface, but also the case where the matte layer is formed via a primer layer or the like. Alternatively, the matte layer 160 may be formed on one surface of the substrate 120 via another support 150 or the like.

[0159] Each layer constituting the laminates 100B, 100C, and 100D will be described below.

[0160] [Matte Layer] The matte layer 160 is a layer having an uneven surface, such as an anti-sticking layer or a light diffusing layer. The matte layer can effectively prevent the wavelength conversion sheet from sticking to the light guide plate 330, the diffusion plate 370, etc., and can diffuse the light incident on and emitted from the wavelength conversion sheet, thereby further improving the light wavelength conversion efficiency.

[0161] 7 to 9, mat layer 160 is a layer containing resin 161 and particles 162, and the particles contained in the mat layer cause at least some of the particles to protrude, forming an uneven surface shape on the surface of this mat layer 160. Here, the phrase "mat layer with at least some of the particles protruding" means that the surface of the mat layer is not uniformly flat, but rather that the particles form undulations on the surface of the mat layer and / or that at least some of the particles are exposed from the surface of the mat layer.

[0162] The matte layer may not contain particles as long as it can form an uneven shape on the surface.

[0163] <Adhesion-preventing layer> When the matte layer 160 is an adhesion-preventing layer, it is possible to effectively prevent the wavelength conversion sheet from sticking to the light guide plate 330, the diffusion plate 370, etc., and also to prevent chipping of the convex parts of the prism sheet 340 due to rubbing.

[0164] Furthermore, by providing the barrier film with an anti-sticking layer, it is possible to prevent the barrier films or wavelength-converting sheets from sticking to each other when they are rolled up, which makes it possible to store or transport the barrier film or wavelength-converting sheet in a roll.

[0165] In particular, when a display device having a light guide plate disposed on the surface of the stick-preventing layer of the wavelength conversion sheet is transported, the stick-preventing layer may rub against the light guide plate, causing scratches on the stick-preventing layer. Alternatively, the stick-preventing layer may rub against the light guide plate, causing fragments to be generated from the stick-preventing layer, which may damage the stick-preventing layer or the light guide plate. Such scratches on the stick-preventing layer or the light guide plate may result in poor appearance of the display device.

[0166] Therefore, in the laminate according to the present embodiment, the proportion of particles protruding from the sticking-preventing layer that are at least twice the thickness of the sticking-preventing layer, i.e., the proportion of particles that are visually recognized as having a particle size at least twice the thickness of the sticking-preventing layer in a planar view of the sticking-preventing layer, is preferably 20% to 80% of the total amount of particles protruding from the sticking-preventing layer. If the proportion of these particles is less than 20%, the scratch resistance of the matte layer may be deteriorated, and further, adhesion between the wavelength conversion sheet and the light guide plate or the like may not be effectively suppressed. Furthermore, if the proportion of these particles is more than 80%, the scratch resistance of the matte layer may be deteriorated. Here, the thickness of the sticking-preventing layer refers to the thickness of the layer of resin 161 that constitutes the sticking-preventing layer.

[0167] The laminate according to the present embodiment has a thickness of 1 mm in plan view of the sticking-preventing layer. ２ It is preferable that the total number of particles in the square is 1800 or more. This may effectively prevent the wavelength conversion sheet from sticking to the light guide plate or the like, and may improve the scratch resistance of the sticking-preventive layer. ２ The upper limit of the total number of particles in the square is not particularly limited, but is preferably 20,000 or less, and more preferably 15,000 or less, for example. ２The total number of particles within the square refers to the total number of particles that are exposed on the surface of the sticking-preventing layer when the sticking-preventing layer is viewed from the surface side, and does not include the number of particles that are buried in the sticking-preventing layer and cannot be seen from the surface.

[0168] The proportion of particles visually recognized as having a particle size twice or more the normal size can be measured, for example, by observing the surface of the sticking prevention layer of a predetermined area (e.g., 258 × 260 μm) in a planar view using a microscope (e.g., a laser microscope or a scanning electron microscope) or a microscope. If necessary, the measurement screen is adjusted so that the planar portion is horizontal. An image is then acquired, and the brightness is adjusted so that the particle portion can be extracted. The particles and their diameters are calculated from the brightness-adjusted image. The proportion of particles visually recognized as having a particle size twice or more the normal size of the thickness of the sticking prevention layer is then calculated from the thickness of the sticking prevention layer calculated from the amount of application, etc.

[0169] 1 mm in plan view of the anti-sticking layer ２ The total number of particles in the square can be calculated by converting the total number of particles in this predetermined area (for example, 258×260 μm) to 1×1 mm.

[0170] In addition, the particle ratio and the area of ​​1 mm ２ As a microscope for determining the total number of particles within the square, for example, OLS4000, a laser microscope manufactured by Olympus Corporation, can be used.

[0171] By providing an anti-adhesion layer in which the proportion of particles protruding from the anti-adhesion layer and the total number of particles in a specified area are within the above-mentioned ranges, scratches on the anti-adhesion layer and the light guide plate (diffusion plate) can be effectively prevented.

[0172] The same applies to a configuration in which an anti-sticking layer is laminated on the surface of the wavelength conversion sheet opposite to the light guide plate (diffusion plate) side and the anti-sticking layer is in contact with the optical film. That is, by providing an anti-sticking layer in which the proportion of particles protruding from the anti-sticking layer and the total number of particles in a given area are within the above-mentioned ranges, it is possible to effectively prevent scratches on the anti-sticking layer and the optical film.

[0173] In particular, when the optical film is a prism sheet, the prisms may be chipped depending on the shape of the prism sheet, making the optical film more susceptible to scratches than other optical films.

[0174] Therefore, when a prism sheet is used as the optical film, by laminating an anti-sticking layer on the surface of the wavelength conversion sheet opposite the light guide plate (diffusion plate) side, in which the proportion of particles protruding from the anti-sticking layer and the total number of particles in a specified area are within the above-mentioned ranges, it is possible to effectively prevent scratches on the optical film (prism sheet).

[0175] The particle 162 has a compressive strength of 2.8 kgf / mm ２ It is preferable that the resin contains a resin having a compressive strength of 3.0 kgf / mm or more. ２ More preferably, it is 4.0 kgf / mm or more. ２ More preferably, it is 2.8 kgf / mm or more. ２ The resin may be, for example, an acrylic resin. ２ By satisfying the above, problems such as crushing or scraping of the particles by foreign matter are less likely to occur, and foreign matter is less likely to directly scratch the surface of the sticking prevention layer, thereby improving scratch resistance. The acrylic resin is a polymer containing, as a monomer component, an ethylenically unsaturated monomer having at least one carboxyl group or carboxylic acid ester group selected from the group consisting of methacrylic acid, acrylic acid, methacrylic acid ester, and acrylic acid ester. Suppose the compressive strength of particle 162 is 2.8 kgf / mm ２ If the thickness is less than this, when foreign matter or the like is mixed in, the particles are crushed or scraped, and the foreign matter is likely to directly scratch the surface of the sticking-preventing layer, thereby reducing scratch resistance, which is undesirable.

[0176] The thickness of the sticking-preventing layer is not particularly limited as long as it can achieve the effects of the present invention. For example, it is preferably 1.0 μm or more and 50.0 μm or less, and more preferably 1.5 μm or more and 10.0 μm or less. The thickness of the sticking-preventing layer means the thickness of the resin portion other than the particles in the sticking-preventing layer, and does not include the thickness of the particle portion exposed (exposed) above the resin. The thickness of the sticking-preventing layer can be measured, for example, by observing the cross section using a scanning electron microscope or the like.

[0177] In order to set the thickness of the sticking-preventing layer within the above range, the coating amount of the sticking-preventing layer after drying is 1.0 g / m ２ 3.6g / m or more ２ Within this range, it is possible to prevent particles from being embedded in the sticking-preventive layer and to prevent impurities from entering between the sticking-preventive layer and the light guide plate. ２ If the coating amount of the anti-sticking layer after drying is less than 3.6 g / m, the anti-sticking layer becomes too thin, and impurities may get between the anti-sticking layer and the light guide plate (diffusion plate), damaging the mat layer or the light guide plate (diffusion plate). ２ If it is more than 10 ...

[0178] The haze value of the sticking-preventing layer is preferably 10% or more and 35% or less, and more preferably 10% or more and 25% or less. When the haze value of the sticking-preventing layer is 10% or more, the number of particles contained in the sticking-preventing layer is sufficient, which can improve the scratch resistance of the sticking-preventing layer and further effectively suppress sticking between the sticking-preventing layer and a light guide plate, etc. When the haze value of the sticking-preventing layer is 35% or less, the scratch resistance of the sticking-preventing layer can be improved, and the function as a display device can be improved.

[0179] If the haze value of the stick-preventing layer is less than 10%, the number of particles contained in the stick-preventing layer will be insufficient, resulting in a deterioration in the scratch resistance of the stick-preventing layer and in the inability to effectively prevent sticking between the stick-preventing layer and the light guide plate. If the haze value of the stick-preventing layer is more than 35%, the scratch resistance of the stick-preventing layer will be deteriorated and, because the haze value is too high, the function as a display device will be reduced. The haze value can be measured using a haze meter in accordance with JIS K7136. The haze value of the matte layer (stick-preventing layer) can be determined by measuring the haze value after forming the stick-preventing layer on a substrate such as a PET film and calculating the difference from the haze value of the substrate PET film alone.

[0180] (Resin) The resin 161 contained in the sticking prevention layer is not particularly limited as long as it is a resin that can achieve the purpose of the sticking prevention layer, and examples thereof include acrylic resins, epoxy resins, urethane resins, polyester resins, polyester acrylate resins, polyurethane acrylate resins, acrylic urethane resins, epoxy acrylate resins, etc. Among these, acrylic resins are preferred from the viewpoint of hardness.

[0181] When an acrylic resin is contained, the proportion of the acrylic resin per 100 parts by mass of the resin contained in the sticking-preventive layer is preferably 60 parts by mass or more, and more preferably 80 parts by mass or more.

[0182] (Particles) The particles are formed in a spherical shape and prevent the light guide plate and the wavelength conversion sheet from sticking together. The type of particles is not particularly limited, and examples thereof include acrylic resins, polystyrene resins, and polyethylene resins. The particles have a compressive strength of 2.8 kgf / mm2 measured in accordance with JIS A 9511. ２It is preferable that the material contains the above resins, and examples thereof include acrylic resins and polystyrene resins. Furthermore, in addition to the acrylic resins and polystyrene resins, particles such as silica fine particles, melamine, nylon, and benzoguanamine fine particles can also be used. The hardness of these materials, in descending order, is silica fine particles, melamine, nylon, polystyrene resin, acrylic resin, and polyethylene resin.

[0183] The average particle size of the particles is preferably 1 μm or more and 50 μm or less, and more preferably 1.5 μm or more and 10 μm or less. When the average particle size of the particles is 1 μm or more, at least a portion of the particles is exposed to a greater extent from the surface of the sticking-preventive layer, which more effectively prevents the sticking between the sticking-preventive layer and the light guide plate 330 and improves the scratch resistance of the sticking-preventive layer. When the average particle size of the particles is 50 μm or less, it is possible to prevent the performance of the sticking-preventive layer from being reduced due to detachment of particles from the sticking-preventive layer and the occurrence of scratches on the sticking-preventive layer due to detached particles.

[0184] The average particle size is obtained as the D50 value in particle size distribution measurement based on JIS Z8820 and Z8822. The average particle size can be measured by, for example, a dynamic light scattering method, a laser diffraction scattering method, or SEM or TEM observation.

[0185] The particle content is preferably 5% by mass or more and 50% by mass or less, and more preferably 10% by mass or more and 40% by mass or less, relative to the total amount of the sticking-preventive layer. By having a content of 5% by mass or more, it is possible to more effectively prevent the sticking-preventive layer from sticking to other members such as a light guide plate. By having a content of 50% by mass or less, it is possible to ensure a sufficient amount of resin for forming the sticking-preventive layer, thereby improving the film-forming properties of the sticking-preventive layer.

[0186] Of the particles contained in the adhesion-preventing layer, the content of particles protruding from the adhesion-preventing layer is preferably 2% by mass or more and 25% by mass or less, and more preferably 5% by mass or more and 20% by mass or less, relative to the total amount of the adhesion-preventing layer.

[0187] The difference in refractive index between the particles and the resin contained in the sticking-preventive layer is preferably 0.5 or less, more preferably 0.3 or less, and even more preferably 0.1 or less.

[0188] (Additives) Additives such as stabilizers, curing agents, crosslinking agents, lubricants, ultraviolet absorbers, and the like may be added arbitrarily to the sticking-preventing layer according to this embodiment, if necessary.

[0189] <Light Diffusion Layer> When the matte layer is a light diffusion layer, it can diffuse light incident on and emitted from the wavelength conversion sheet, thereby further increasing the light wavelength conversion efficiency. Note that the light diffusion layer may not contain particles as long as it can form an uneven shape on the surface.

[0190] When the light diffusion layer contains a resin and particles, the same resin and particles as those contained in the sticking prevention layer can be used, and therefore a description thereof will be omitted here.

[0191] 8 and 9, in the laminate according to the present embodiment, a support 150 may be disposed between the barrier film and the matte layer 160. The support 150 is a layer mainly containing a resin, and the same resin as that described for the substrate 120 can be used as the resin.

[0192] 8 and 9 , the thickness of the support 150 is preferably more than 25 μm and not more than 200 μm, more preferably from 38 μm to 175 μm, and even more preferably from 50 μm to 150 μm. When the thickness of the support 150 is more than 25 μm and not more than 200 μm, the flexibility of the wavelength-conversion sheet is improved, and the handling property when combined with a backlight light source of a display device is improved.

[0193] In order to avoid blocking of light from the backlight source, the support preferably has a high total light transmittance as measured in accordance with JIS K 7361. Specifically, the support preferably has a total light transmittance as measured in accordance with JIS K 7361 of 85% or more, more preferably 90% or more.

[0194] 8 and 9, the laminate according to the present embodiment may have a tacky-adhesive layer 140 disposed between the barrier film and the support 150. The tacky-adhesive layer refers to a pressure-sensitive adhesive layer or an adhesive layer. Examples of adhesives that can be used to form the adhesive layer 140 include polyvinyl acetate adhesives, polyacrylic acid ester adhesives made from homopolymers such as ethyl acrylate, butyl acrylate, and 2-ethylhexyl ester, or copolymers of these with methyl methacrylate, acrylonitrile, styrene, and the like, cyanoacrylate adhesives, ethylene copolymer adhesives made from copolymers of ethylene with monomers such as vinyl acetate, ethyl acrylate, acrylic acid, and methacrylic acid, cellulose adhesives, polyester adhesives, polyamide adhesives, polyimide adhesives, amino resin adhesives made from urea resin or melamine resin, phenol resin adhesives, epoxy adhesives, polyurethane adhesives, reactive (meth)acrylic adhesives, rubber adhesives made from chloroprene rubber, nitrile rubber, styrene-butadiene rubber, and the like, silicone adhesives, and inorganic adhesives made from alkali metal silicates and low-melting-point glass, and the like.

[0195] The adhesive constituting the adhesive layer is not particularly limited as long as it has the desired adhesive strength, and examples thereof include acrylic, urethane, rubber, and silicone adhesives. Among these, acrylic adhesives are preferred because of their excellent durability, such as heat resistance, transparency, and low cost. Examples of acrylic adhesives include acrylic ester copolymers obtained by copolymerizing acrylic esters with other monomers. Examples of acrylic esters include ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, isononyl acrylate, hydroxyethyl acrylate, propylene glycol acrylate, acrylamide, and glycidyl acrylate. These may be used alone or in combination of two or more.

[0196] Examples of the other monomers include methyl acrylate, methyl methacrylate, styrene, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid, itaconic acid, hydroxylethyl acrylate, hydroxylethyl methacrylate, propylene glycol acrylate, acrylamide, methacrylamide, glycidyl acrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, tert-butylaminoethyl methacrylate, and n-ethylhexyl methacrylate, and these may be used alone or in combination of two or more.

[0197] The composition system of the adhesive layer may be any of the composition types such as aqueous type, solution type, emulsion type, dispersion type, etc., and the properties thereof may be any of the types such as film / sheet type, powder type, solid type, etc., and the adhesive mechanism may be any of the types such as chemical reaction type, solvent evaporation type, heat melting type, heat pressure type, etc.

[0198] The adhesive layer can be applied by, for example, roll coating, gravure coating, knife coating, dip coating, spray coating, other coating methods, or printing methods, and the coating amount is 0.1 g / m ２ 10g / m or more ２ The following (dry state) is desirable.

[0199] Instead of the adhesive layer made of the adhesive, a resin layer formed of, for example, a thermosetting resin or a thermoplastic resin containing a crosslinking agent, etc. may be laminated. Furthermore, a bonding method using extrusion lamination may be used in which a thermoplastic resin such as EVA, ionomer, polyvinyl butyral (PVB), polyethylene resin, etc. is melted and the molten thermoplastic resin is extruded and laminated.

[0200] <<Wavelength Conversion Sheet>> Figures 10 and 11 are cross-sectional views showing examples of the wavelength conversion sheet of the present invention. Specifically, a wavelength conversion sheet 200B in Figure 10 includes a phosphor layer 110 containing phosphor 112 and sealing resin 111, and laminates 100B laminated on both surfaces of the phosphor layer 110 via pressure-sensitive adhesive or adhesive layers 170 (hereinafter referred to as adhesive layers 170). A wavelength conversion sheet 200D in Figure 11 includes a phosphor layer 110 containing phosphor 112 and sealing resin 111, and laminates 100D laminated on both surfaces of the phosphor layer 110 via adhesive layers 170. By laminating the laminates of the present invention on both surfaces of the phosphor layer 110, barrier properties are imparted to the phosphor layer. In this specification, both surface sides of the phosphor layer mean both the surface side on which the light source is located (light incident side) and the surface side opposite to the side on which the backlight light source is located (light exit side) when the wavelength conversion sheet is used as a backlight light source.

[0201] 10 and 11, matte layers are arranged on both outermost layers of the laminate, but the wavelength conversion sheet is not limited thereto, and may have a configuration in which the laminate according to the present invention is laminated only on the surface on the light guide plate or diffusion plate side (not shown). Alternatively, the laminate according to the present invention may be laminated only on the surface on the light output side (viewing side) (not shown). Alternatively, no matte layer may be formed, and a barrier film as shown in FIG. 1 may be laminated alone on at least one surface of the phosphor layer.

[0202] [Phosphor Layer] The phosphor layer 110 is a layer for adjusting the emission wavelength of light emitted from the backlight light source. The phosphor layer 110 contains one or more types of phosphors made of quantum dots.

[0203] The quantum dots forming the phosphor 112 are semiconductor particles of a predetermined size that exhibit a quantum confinement effect. When the quantum dots absorb light from an excitation source and reach an energy excited state, they emit energy corresponding to the energy bandgap of the quantum dots. By adjusting the size or material composition of the quantum dots, the energy bandgap can be adjusted, thereby obtaining energy in various levels of wavelength bands. In particular, quantum dots can generate strong fluorescence in a narrow wavelength band. This allows the display device to be illuminated with light of the three primary colors with excellent color purity, thereby achieving a display device with excellent color reproducibility.

[0204] The phosphor is not particularly limited, and examples thereof include particles containing at least one selected from the group consisting of a II-VI compound, a III-V compound, a IV-VI compound, and a IV compound. From the viewpoint of luminous efficiency, the phosphor preferably contains a compound containing at least one of Cd and In.

[0205] Specific examples of II-VI compounds include CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, and the like. Specific examples of III-V compounds include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and the like. Specific examples of Group IV-VI compounds include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, etc. Specific examples of Group IV compounds include Si, Ge, SiC, SiGe, etc.

[0206] The phosphor preferably has a core-shell structure. By making the band gap of the compound constituting the shell wider than that of the compound constituting the core, it is possible to further improve the quantum efficiency of the phosphor. Examples of combinations of core and shell (core / shell) include CdSe / ZnS, InP / ZnS, PbSe / PbS, CdSe / CdS, CdTe / CdS, and CdTe / ZnS.

[0207] The phosphor may also have a multi-layer shell structure, i.e., a core-multi-shell structure, in which one or more narrow bandgap shells are stacked on a wide bandgap core, and a wide bandgap shell is further stacked on the shells, thereby further improving the quantum efficiency of the phosphor.

[0208] The phosphor layer 110 can be formed by laminating a sealing resin 111 containing phosphor 112. For example, the phosphor layer 110 can be formed by applying a mixed liquid containing phosphor 112 and sealing resin 111 to the surface of the base layer and curing the mixture. Examples of the sealing resin 111 include photopolymerized resins such as acrylic resins, such as polyester (meth)acrylate, urethane (meth)acrylate, polyester-urethane (meth)acrylate, polyether (meth)acrylate, polyol (meth)acrylate, melamine (meth)acrylate, isocyanurate (meth)acrylate, epoxy (meth)acrylate, and (meth)acrylate resins; thermosetting resins such as phenolic resin, urea resin, melamine resin, epoxy resin, unsaturated polyester resin, polyester resin, silicone resin, and polyurethane resin; and thermoplastic resins, such as EVA, ionomer, polyvinyl butyral (PVB), and polyethylene-based resins, containing a crosslinking agent or the like. From the viewpoint of adhesion between the phosphor layer and the base layer, it is preferable to include at least one resin selected from the group consisting of acrylic resin, epoxy resin, urethane resin, and polyester resin. These may be used alone or in combination. An adhesive layer may be formed to enhance adhesion.

[0209] 3, the wavelength conversion sheet according to the present embodiment may have an adhesive layer 170 disposed between the laminate and the phosphor layer 110. As the adhesive layer 170, the same adhesive as that described for the adhesive layer 140 can be used, and therefore the description thereof will be omitted here.

[0210] <Method for manufacturing wavelength conversion sheet> The wavelength conversion sheet is manufactured by, for example, forming an adhesive layer 170 on the surface of the covering layer 130a side of two laminates 100B, and applying a mixed liquid (ink) containing phosphor 110 and sealing resin 111 to the surface of the adhesive layer of one of the laminates 100B. The mixed liquid (ink) is then brought into contact with the surface of the adhesive layer 170 of the other laminate 100B and cured, thereby manufacturing the wavelength conversion sheet 200B shown in FIG. 10 . The wavelength conversion sheet 200D shown in FIG. 11 can be manufactured in a similar manner. Alternatively, the mixed liquid (ink) containing phosphor 110 and sealing resin 111 may be applied directly to the surface of the laminate without forming the adhesive layer 170.

[0211] <<Display Device>> A display device including the above-mentioned wavelength conversion sheet will be described with reference to Figs. 12 to 14. Fig. 12 is a perspective view schematically illustrating the configuration of a surface-mounted display device according to one embodiment of the present invention. Fig. 13 is a cross-sectional view of the display device shown in Fig. 12. The cross-sectional view shown in Fig. 13 is a cross-sectional view of a cross section parallel to the direction in which the wavelength conversion sheets 200B (200D) and the like constituting the display device are stacked, and parallel to the direction in which the light source unit and the light guide plate are aligned (the direction in which light emitted from the light source unit travels). Fig. 14 is a cross-sectional view schematically illustrating the configuration of a direct-type display device according to one embodiment of the present invention.

[0212] The display device 300A shown in Figures 12 and 13 includes an LCD panel 360, a polarized light selective reflection sheet 350, a prism sheet 340, a wavelength conversion sheet 200B (200D), a light guide plate 330, and a reflection sheet 320 stacked in this order. The display device 300A also includes a light source unit 310 arranged along at least one end face (side face) of the light guide plate 330. The light source unit 310, the light guide plate 330 or a diffusion plate 370 (described later), and the wavelength conversion sheet 200B (200D) constitute the backlight member of the present invention. The LCD panel 360 is a transmissive display unit formed of a transmissive liquid crystal display element that forms video information on its display surface. The polarized light selective reflection sheet 350 is a sheet-like member that transmits light of a specific polarization state and reflects light of other polarization states; for example, the DBEF series (manufactured by Sumitomo 3M Limited) can be used. When using such a polarized light selective reflection sheet 350, it is preferable from the viewpoint of improving brightness and light utilization efficiency to arrange the polarized light selective reflection sheet 350 so that its transmission axis is parallel to the transmission axis of a polarizing plate (not shown) located on the light entrance side of the LCD panel 360. The prism sheet 340 is an optical sheet that has the effect of deflecting (concentrating) the traveling direction of light emitted from the upper surface of the light guide plate 330 toward the front (the normal direction to the panel surface of the LCD panel).

[0213] The light guide plate 330 is a substantially flat-plate-shaped member that guides light. The light guide plate 330 receives light emitted by the light source unit 310 from one end surface of the flat-plate-shaped member, guides the light by total reflection at the upper and lower surfaces of the light guide plate 330, and appropriately emits the light from the upper surface of the light guide plate 330 toward the prism sheet 340. The reflection sheet 320 is a sheet-shaped member that can reflect light. It is disposed on the side of the light guide plate 330 opposite the prism sheet 340 and has the function of reflecting light emitted from the lower surface of the light guide plate 330 back into the light guide plate 330, thereby improving the utilization efficiency of light emitted from the light source unit 310. From the viewpoint of improving the utilization efficiency of light, it is preferable that the reflection sheet 320 primarily have specular reflectivity (regular reflectivity). The reflective sheet 320 may be, for example, a sheet-like member in which at least the reflective surface (the surface facing the light guide plate 330) is formed of a highly reflective material such as metal, or a sheet-like member including a surface layer made of a thin film (e.g., a metal thin film) formed of a highly reflective material. The reflective sheet 320 is not limited to this, and may be, for example, a sheet-like member made of a white resin that is primarily diffusely reflective and has a high reflectivity. The light source unit 310 is a light source that emits light to illuminate the LCD panel 360. The light source unit 310 is formed, for example, by arranging a plurality of point light sources at predetermined intervals in order to uniformly incident light on one end surface of the light guide plate 330. The point light source may be, for example, a light-emitting diode (LED) light source or an organic electroluminescence (EL) light source. 12 and 13 is a so-called surface-mounted display device in which light emitted from a light source unit 310, which is a backlight light source arranged on an end surface of a light guide plate 330, enters the light guide plate 330, is guided within the light guide plate, and the light emitted from the upper surface of the light guide plate 330 is transmitted sequentially through the wavelength conversion sheet 200B (200D), the prism sheet 340, the polarization selective reflection sheet 350, and the LCD panel 360. The reflection sheet 320 is provided as needed.

[0214] In a so-called surface-mounted display device 300A, the wavelength conversion sheet 200B (200D) is disposed so as to be in contact with the light guide plate 330. Here, in the case of a conventional barrier film for a wavelength conversion sheet or a wavelength conversion sheet, the barrier film and the light guide plate are stuck together, which is a factor in significantly deteriorating the display characteristics of the liquid crystal display device. Furthermore, when the display device is transported, the wavelength conversion sheet and the light guide plate rub against each other, which damages the wavelength conversion sheet and / or the light guide plate, which is also a factor in deteriorating the display characteristics of the display device.

[0215] However, if the display device has a light guide plate disposed on the surface of the matte layer of the wavelength conversion sheet, even if it is a surface-mount type display device, it is possible to effectively prevent the barrier film and the light guide plate from sticking together and to prevent the wavelength conversion sheet and / or the light guide plate from being damaged.

[0216] Furthermore, a conventionally known light guide plate can be used as the light guide plate, but in order to more effectively prevent the barrier film from sticking to the light guide plate, the surface of the light guide plate that comes into contact with the barrier film can also be wedge-shaped.

[0217] Another display device provided with the wavelength conversion sheet will be described with reference to Fig. 14. The display device 300B in Fig. 14 is a so-called direct type display device in which a light source unit 380 is arranged on the rear side of a diffuser plate 370, and a wavelength conversion sheet 200B (200D) is arranged on the side of the diffuser plate 370 opposite to the light source unit 380, and light irradiated from the light source unit 380 is irradiated onto the wavelength conversion sheet 200B (200D) via the diffuser plate 370.

[0218] In this embodiment, a prism sheet 340, a polarized light selective reflection sheet 350, and an LCD panel 360 are laminated in this order on the side of the wavelength conversion sheet 200B (200D) opposite to the diffuser plate 370, as in the display device 300A shown in Figures 9 and 10 described above. Furthermore, a reflection sheet 320 is provided on the side of the light source unit 380 opposite to the diffuser plate 370, and light emitted from the light source unit 380 that is reflected without being incident on the diffuser plate 370 is reflected back toward the diffuser plate 370, thereby improving light utilization efficiency. The light source unit 380 shown in Figure 11 is formed by arranging a plurality of point light sources (LEDs) at equal intervals in a lattice pattern along the plate surface of the diffuser plate 370.

[0219] In the so-called direct-type display device 300B, the wavelength conversion sheet 200B (200D) is arranged so as to be in contact with the diffuser plate 370. By arranging the diffuser plate 370 on the surface of the matte layer 160 of the wavelength conversion sheet 200B (200D), it is possible to effectively prevent the barrier film and the diffuser plate from sticking together for the same reason as in the case of the display device 300A, and also to prevent the wavelength conversion sheet and / or the diffuser plate from being damaged.

[0220] <Manufacturing Method of Display Device> The display device can be manufactured through a step of arranging a light guide plate or a diffusion plate on the surface of the matte layer of the wavelength conversion sheet.

[0221] <Suppression of occurrence of black lines> When a wavelength conversion sheet is irradiated with primary light in an inspection process before being incorporated into a display device such as a liquid crystal display, dark areas such as black lines may occur in part of the surface of the wavelength conversion sheet. Dark areas tend to occur in part of the surface of the wavelength conversion sheet. For this reason, wavelength conversion sheets with no quality problems can be obtained by selecting only wavelength conversion sheets that do not contain dark areas as non-defective products. However, the selection method as described above significantly reduces the yield of wavelength conversion sheets. For this reason, it is necessary to suppress the occurrence of dark areas such as black lines over time.

[0222] When the wavelength conversion sheet is illuminated with a commercially available blue LED or black light, dark areas such as black lines are visible, measuring approximately 1 mm in width and 50 mm or more in length. The inventors have found that dark areas such as black lines are caused by partial cracks in the barrier layer of the wavelength conversion sheet, which cause the quantum dots to deteriorate over time. The wavelength conversion sheet of the present invention can prevent the dark areas such as black lines from appearing over time. Details will be described in the examples below.

[0223] The present invention will be described in further detail below with reference to examples, but the present invention is not limited to these descriptions. First, barrier films according to Examples 1 to 4 and Comparative Examples 1 to 12 were produced using the film formation apparatus 10, which is the film formation apparatus and film formation method described in this embodiment. Pretreatment conditions, deposition conditions, etc. are summarized in Tables 1 and 2.

[0224] Example 1 A biaxially stretched polyethylene terephthalate film (PET film, product name: PET-F manufactured by Unitika Ltd.) having a thickness of 12 μm was used as the substrate 1, and a plasma pretreatment process and a film formation process were carried out using the film formation apparatus 10 shown in FIG.

[0225] First, the PET substrate 1 used was a PET substrate that had been subjected to a humidity conditioning process in which the roll was rewound in an atmosphere of 25°C and 50% RH, and then stored at 25°C and 50% RH for 3 days to condition the humidity.

[0226] In the pretreatment step, plasma pretreatment was performed on the surface of the substrate 1 using the plasma pretreatment mechanism 11B shown in Figures 2 and 3. Specifically, first, a plasma-forming gas was supplied to the plasma pretreatment chamber 12B using the plasma raw material gas supply unit, while the air pressure inside the plasma pretreatment chamber 12B was adjusted using the reduced pressure chamber 12. Next, a voltage was applied between the pretreatment roller 20 and the electrode unit 21 to generate plasma, and plasma pretreatment was performed on the surface of the substrate 1. The plasma pretreatment was performed under the following conditions. <Pretreatment conditions> Substrate conveying speed: 670 m / min High frequency power output: 4 kW High frequency power frequency: 40 kHz Plasma intensity: 550 W sec / m ２Plasma forming gas: oxygen 100 (sccm), argon 1000 (sccm) Magnetic forming means: 1000 gauss permanent magnet Voltage applied between pretreatment drum and plasma supply nozzle: 420 V Pressure in pretreatment section: 2.0 x 10 －１ Pa

[0227] In the film formation process, a vapor deposition film containing aluminum oxide was formed by vacuum deposition using a resistance heating type (represented as RH in Table 1) evaporation mechanism 24 as shown in Fig. 6. Specifically, while aluminum metal wires were supplied into a boat 24b as a vapor deposition material, the vapor deposition material in the boat 24b was heated using the resistance heating type evaporation mechanism 24, and the aluminum was evaporated so as to reach the surface of the substrate 1. At the same time, a vapor deposition film was formed on the surface of the substrate 1 while oxygen was supplied.

[0228] 6 and anodes (not shown) disposed on both sides of the substrate 1 in the width direction as viewed from the boat 24b, facing the opening of the hollow cathode 51. A plasma source gas (argon gas) was supplied to the hollow cathode 51, and a discharge was generated to excite plasma. This plasma was then extracted by the opposing anode between the surface of the substrate 1 and the evaporation mechanism 24, thereby performing plasma assist during deposition. The plasma assist conditions were as follows: argon gas supply rate to the hollow cathode: 80 sccm, anode current: 168 A, and anode voltage: 23 V. Note that no plasma post-treatment process was performed after the plasma assist process during deposition.

[0229] Using the above method, a first vapor-deposited film was laminated on the substrate 1. The conveying speed was 670 m / min, and the thickness of the vapor-deposited film was 8.0 nm. The light transmittance at a wavelength of 366 nm measured in-line after vapor deposition was set to 100% based on the transmittance of the substrate 1 in a pre-treated state without vapor deposition. Vapor deposition was then initiated, and the oxygen supply rate was feedback-controlled to achieve a light transmittance of 99.7%. The pressure during vapor deposition was 1.1 Pa.

[0230] The barrier film roll that had undergone the above-described film-forming process was subjected to an aging treatment at 55° C. and 50% RH for 3 days.

[0231] Furthermore, a first coating layer was laminated on the first vapor-deposited film. Polyvinyl alcohol having a saponification degree of 99% or more and a degree of polymerization of 2400 was mixed as a water-soluble polymer with a liquid of water and isopropyl alcohol in a ratio of 95 / 5 to obtain solution A adjusted to a solid content of 4%. Water, isopropyl alcohol, and 1N hydrochloric acid were mixed in a ratio of 65 / 34 / 1 to obtain solution B. Tetraethoxysilane was used as a metal alkoxide to prepare solution C. A liquid obtained by adjusting the ratio of solution B and solution C and mixing it was used as solution D, and a liquid obtained by adjusting the ratio of solution A and solution D and mixing it was used as a barrier coating agent. The barrier coating agent had a solid content of 5% after mixing, with the SiO of tetraethoxysilane being 5% relative to the solid content of PVA. ２ The ratio of solution B to solution C and the ratio of solution A to solution D were adjusted so that the converted mass was 2.0. This barrier coating agent was designated as solution X.

[0232] The barrier coating agent prepared above was coated onto the first vapor-deposited film by a direct gravure method. The film was then dried at 140°C to form a coating layer with a dry thickness of 200 nm, and then aged at 25°C and 50% RH for 3 days to form a first coating layer. The dry film thickness was controlled by changing the gravure plate.

[0233] Next, a second vapor-deposited film was formed on the first coating layer under the same conditions as for the first vapor-deposited film described above, and further, a second coating layer was formed on the second vapor-deposited film under the same conditions as for the first coating layer described above, except that the thickness of the coating layer was set to 230 nm, thereby producing the barrier film of Example 1.

[0234] Example 2 A barrier film of Example 2 was produced in the same manner as in Example 1, except that the plasma assist conditions were an anode current of 155 A and an anode voltage of 20 V.

[0235] (Example 3) In the film formation process, the first vapor-deposited film and the second vapor-deposited film were formed under the same conditions as in Example 2, except that the transport speed was 530 m / min, the oxygen supply amount was feedback-controlled so as to achieve a light transmittance of 98.0%, the pressure during vapor deposition was 1.0 Pa, and the film thickness was 10.0 nm.

[0236] In the coating layer forming process, solution Y was used. When mixing solutions B and C, 5% of glycidoxypropyltrimethoxysilane was added relative to the weight of tetraethoxysilane, and then the solid content was 5% and the SiO content of tetraethoxysilane relative to the solid content of PVA was 100%. ２ The barrier film of Example 3 was produced in the same manner as in Example 2, except that the ratio of Solution B to Solution C and the ratio of Solution A to Solution D were adjusted and mixed so that the converted mass was 3.4, to form a barrier coating agent called Solution Y, the film thickness of the first coating layer was 300 nm, the film thickness of the second coating layer was 300 nm, and the aging treatment after formation of the coating layer was carried out at 55°C and 50% RH for 3 days.

[0237] Example 4 In the film formation process, the first and second vapor-deposited films were formed in the same manner as in Example 3, except that the plasma assist conditions were an anode current of 141 A and an anode voltage of 22 V.

[0238] In the coating layer forming step, the barrier film of Example 4 was produced in the same manner as in Example 2, except that Solution X was used.

[0239] Comparative Example 1 The same procedures as in Example 2 were carried out except that in the film formation step of the first vapor-deposited film, the conveying speed was 600 m / min, the film thickness was 8.9 nm, and the aging treatment after film formation was not performed. In addition, no second vapor-deposited film was formed.

[0240] In the step of forming the first coating layer, solution Y was used, and the same procedure as in Example 3 was carried out. The barrier film of Comparative Example 1 was produced without forming the second coating layer.

[0241] Comparative Example 2 A barrier film of Comparative Example 2 was produced in the same manner as in Comparative Example 1, except that in the film formation step of the first vapor-deposited film, the aging treatment after film formation was carried out at 50°C and 50% RH for 2 days.

[0242] Comparative Example 3 A barrier film of Comparative Example 3 was produced in the same manner as in Comparative Example 1, except that in the film formation step of the first vapor-deposited film, the aging treatment after film formation was carried out at 55°C and 50% RH for 3 days.

[0243] Comparative Example 4 The same procedures as in Comparative Example 3 were carried out except that in the film formation process of the first vapor deposition film, the oxygen supply amount was feedback-controlled so that the light transmittance was 94.0%, the pressure during vapor deposition was set to 0.3 Pa, the film thickness was set to 8.0 nm, and plasma assistance was not performed. A second vapor deposition film was not formed.

[0244] In the step of forming the first coating layer, Solution X was used, and the same procedure as in Example 1 was carried out. The barrier film of Comparative Example 4 was produced without forming the second coating layer.

[0245] Comparative Example 5 was the same as Comparative Example 4, except that in the film-forming step of the first vapor-deposited film, an EB (electron beam) heating method (referred to as EB in Table 1) was used instead of a resistance heating method, the oxygen supply amount was feedback-controlled so as to achieve a light transmittance of 88.0%, and the pressure during vapor deposition was set to 0.2 Pa. A second vapor-deposited film was not formed.

[0246] In the step of forming the first coating layer, Solution X was used, and the same procedure as in Example 1 was carried out. The barrier film of Comparative Example 5 was produced without forming the second coating layer.

[0247] Comparative Example 6 A barrier film of Comparative Example 6 was produced in the same manner as in Example 1, except that in the film-forming step, the plasma-assisted conditions were an anode current of 175 A and an anode voltage of 24 V.

[0248] (Comparative Example 7) The barrier film of Comparative Example 7 was produced in the same manner as in Comparative Example 6, except that in the humidity conditioning step, the film was rewound at 30°C and 60% RH and then stored at 30°C and 60% RH for 3 days to condition the humidity, and in the film formation step, the aging treatment after film formation was carried out at 60°C and 50% RH for 4 days.

[0249] Comparative Example 8 A barrier film of Comparative Example 8 was produced in the same manner as in Example 2, except that the aging treatment after film formation was not carried out in the film formation step.

[0250] Comparative Example 9 A barrier film of Comparative Example 9 was produced in the same manner as in Example 2, except that in the film-forming step, the plasma-assisted conditions were an anode current of 47 A and an anode voltage of 21 V.

[0251] Comparative Example 10 A barrier film of Comparative Example 10 was produced in the same manner as in Example 2, except that in the film formation step, the conveying speed was 600 m / min, the oxygen supply amount was feedback-controlled so as to achieve a light transmittance of 94.0%, the pressure during deposition was 0.3 Pa, and plasma assist was not performed.

[0252] (Comparative Example 11) In the film formation process, a 12 μm thick biaxially oriented polyethylene terephthalate film (PET film, product name: P60 manufactured by Toray Industries, Inc.) was used as the substrate 1, and an acrylic urethane resin anchor coat layer (referred to as AC in Table 1) was formed to a thickness of 200 nm on the substrate 1. Instead of the resistance heating method, an EB (electron beam) heating method (referred to as EB in Table 1) was used, and the plasma pretreatment process was not performed. The transport speed was 480 m / min, and the oxygen supply amount was feedback controlled so that the light transmittance at a wavelength of 366 nm measured in-line after deposition was 88.0%, and the pressure during deposition was 0.2 Pa. The film formation process and aging treatment were performed in the same manner as in Example 3, except that the pressure during deposition was 0.2 Pa and plasma assistance was not performed. Note that the light transmittance at a wavelength of 366 nm measured in-line after deposition was set to 100% based on the transmittance of the substrate 1 and the anchor coat layer when no deposition was performed.

[0253] In the coating layer forming step, solution Z was used. When mixing solutions B and C, 15% of 1,3,5-tris(3-trialkoxysilylpropyl)isocyanurate was added relative to the weight of tetraethoxysilane, and a coating layer was formed with a solid content of 7% and a SiO content of tetraethoxysilane relative to the solid content of PVA. ２ A barrier coating agent was prepared by mixing the solutions B and C and the solution A and D at adjusted ratios so that the converted mass was 4.0, and this was designated as solution Z. The barrier film of Comparative Example 11 was produced in the same manner as in Example 3, except that the film thickness of the first coating layer was 210 nm and the film thickness of the second coating layer was 210 nm.

[0254] Comparative Example 12 A barrier film of Comparative Example 12 was produced in the same manner as in Comparative Example 11, except that in the coating layer forming step, the first coating layer had a thickness of 200 nm and the second coating layer had a thickness of 160 nm.

[0255] (Comparative Example 13) In the film formation process of the first vapor deposition film in Example 2, an aging treatment after film formation was carried out at 60°C and 80% RH for 5 days. However, the film broke when unwound to form the first coating layer, so no further evaluation was performed.

[0256]

[0257]

[0258] [Acquisition and Analysis of XAFS Spectra] XAFS spectra were obtained under the following measurement conditions for the barrier films of Examples 1 to 4 and Comparative Examples 1 to 10. Of these, the results for Example 3 are shown in Figure 15. The vertical axis in the figure represents the intensity of the emitted fluorescent X-rays (shown as absorption intensity (a.u) in the figure), and the horizontal axis represents the light (or X-ray) energy (eV).

[0259] <XAFS spectrum acquisition> ・Line used: Aichi Synchrotron Light Center BL1N2 ・Acceleration energy: 1.2 GeV ・Beam size: 1.0 mm horizontal x 1.0 mm vertical ・Angle of incidence to sample: 22.5° (the direction perpendicular to the sample is 0°) ・Entrance slit: 30 μm ・Exit slit: 30 μm ・Measurement method: Partial fluorescence yield method ・Energy range (Al K-edge): 1500-1700 eV ・Energy step: 1500-1550 eV: 2.0 eV / step 1550-1555 eV: 1.0 eV / step 1555-1575 eV: 0.2 eV / step 1575-1600 eV: 0.5 eV / step 1600 to 1680 eV: 1.0 eV / step 1680 to 1700 eV: 2.0 eV / step (Storage time: all 10 s / point) Energy calibration: Energy calibration using Au 4f 7 / 2 on an Au plate (calibrated using the value obtained by subtracting the theoretical value of 1500 eV from the actual measured value)

[0260] <XAFS Spectral Analysis> Peak Separation Method Intensity values ​​were normalized so that the absorption spectrum intensity value at an absorption X-ray energy value of 1540 eV was 0 and the absorption spectrum intensity value at an absorption X-ray energy value of 1680 eV was 1.

[0261]

[0262] The normalized data points from 1555 eV to 1575 eV and from 1595 eV to 1605 eV were extracted, and the above f(x) function was fitted to determine each coefficient. １ = k ２ , K. １ =X １ , K. ２ =X ２ The constraints are included. Fitting was performed using the least squares method. In this case, the least squares function in the Python scipy library was used, and the initial values ​​of the coefficients were calculated by giving the values ​​shown in the table below. The symbols for the above functions are defined as follows: M ｉ : Weighting factor of Gaussian function and Lorentzian function at the i-th absorption peak X ｉ : Peak center of the i-th absorption peak h ｉ : Peak intensity factor β of the i-th absorption peak ｉ : Peak width factor k of the i-th absorption peak ｊ : baseline intensity factor K in the jth baseline ｊ : Half-division position of the baseline intensity in the jth baseline

[0263]

[0264] The results of peak separation of the XAFS spectra of Example 3 and Comparative Examples 2, 4, and 11 are shown in Figures 16 to 19. Figure 16 shows the analysis result of separating the XAFS peaks of Example 3, Figure 17 shows the analysis result of separating the XAFS peaks of Comparative Example 2, Figure 18 shows the analysis result of separating the XAFS peaks of Comparative Example 4, and Figure 19 shows the analysis result of separating the XAFS peaks of Comparative Example 10.

[0265] "Experiment" is the measured XAFS spectrum, "Fit. Peak 1" is the isolated intensity peak near 1566 eV, "Fit. Peak 2" is the isolated intensity peak near 1568 eV, and "Fit. Peak 3" is the isolated intensity peak near 1572 eV. From this, the XAFS peak top ratio P = (intensity peak top near 1572 eV) / (intensity peak top near 1566 eV) was calculated, and the results are shown in Table 4 for the barrier films of Examples 1 to 4 and Comparative Examples 1 to 10.

[0266] <TOF-SIMS analysis> For the barrier films of Examples 1 to 4 and Comparative Examples 1 to 10, C in the barrier film was analyzed. ２ － ion (mass number 24,000), CN － ion (mass number 26.0003), Si － ion (mass number 27.9777), AlO ２ － ion (mass number 58.971), SiO ２ － The intensity of the ion (mass number 59.9666) was measured using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Specifically, using a time-of-flight secondary ion mass spectrometer (TOF.SIMS5, manufactured by ION TOF), mass analysis of various ions in each layer was performed while repeatedly soft etching from the surface of the barrier film to the PET film side at a constant rate using a Cs (cesium) ion gun. Coating layer intensity ratio X = C ２ － Ionic strength / Si － The results as ion intensity are shown in Table 4 (C2 / Si intensity ratio in Table 4). TOF-SIMS measurement conditions Primary ion type: Bi ３＋＋ (0.2 pA, 100 μs) ・Measurement area: 150 x 150 μm ２ Scan: 128 pixels x 128 pixels x 1 scan Etching gun type: Cs (1 keV, 60 nA) Etching area: 600 x 600 μm ２ Etching rate: 10 sec / Cycle Vacuuming time: 1 x 10 －６・TOF-SIMS measurement was carried out within 30 hours after the start of evacuation.

[0267] 20 to 22 show graphical analysis diagrams of the measurement results. Fig. 20 shows the measurement results of Example 3, Fig. 21 shows the measurement results of Comparative Example 10, and Fig. 22 shows the measurement results of Comparative Example 11. In the figures, the unit of the vertical axis (intensity) is the intensity of secondary ions, and the unit of the horizontal axis (Et times (s)) is the number of seconds that etching was performed.

[0268]

[0269] <Measurement of Barrier Properties of Barrier Film> The water vapor permeability and oxygen permeability of the barrier films of Examples 1 to 4 and Comparative Examples 1 to 10 were measured.

[0270] Water vapor permeability (g / (m ２ The water vapor transmission rate (cc / (m)) was measured using a water vapor transmission rate measuring device (manufactured by Mocon, product name "PERMATORAN-W 3 / 31") under the measurement conditions of 40°C and 100% RH in accordance with JIS K 7129 B method. ２ The oxygen transmission rate (OTR) (days atm, indicated as "OTR" in the table) was measured using an oxygen transmission rate measuring device (manufactured by Mocon, product name "OX-TRAN 2 / 20") under measurement conditions of 23°C and 90% RH in accordance with JIS K 7126-2. The results are shown in Table 5.

[0271] <Evaluation of Luminance Maintenance Rate> For the barrier films of Examples 1 to 4 and Comparative Examples 1 to 10, wavelength conversion sheets having the following layer configurations were prepared.

[0272] First, a matte layer 160 was formed on one surface of a support 150 (biaxially stretched PET film, thickness: 38 μm), and then a pressure-sensitive adhesive layer 140 (two-component curing polyurethane adhesive, thickness when dried: 5 μm) was applied thereto by gravure roll coating, dried, and laminated on the surface of the coating layer side of the barrier film 130 of Example 1 described above, thereby obtaining two laminates 100D shown in FIG. 9 .

[0273] The mat layer 160 includes spherical particles 162 containing a polyacrylic resin (Eposter MA (an acrylic cross-linked material having a compressive strength of 2.8 kgf / mm ２ The above resin (average particle size: 4 μm) was mixed with an acrylic resin to prepare a coating agent for forming a matte layer, which was then applied to the substrate by gravure roll coating (particle content: 1.7% by mass, dry coating amount: 1.6 g / m ２ , matte layer thickness 1.5 μm).

[0274] Next, the following adhesive layer coating liquid was applied to the surface of the substrate 120 and dried to form an adhesive layer 170. <Adhesive Layer Coating Liquid> Polyester polyol 50 parts by mass (hydroxyl value: 62 mg KOH / g, solid content 20% by mass) Silane coupling agent 1 part by mass (3-glycidoxypropylmethyldimethoxysilane) Silica filler 1 part by mass (average particle size 5 μm) Curing agent 1 part by mass (1,6-hexamethylene diisocyanate, solid content 35% by mass) Solvent 50 parts by mass (methyl ethyl ketone)

[0275] Furthermore, a phosphor coating solution containing the following phosphor 112 was applied to the adhesive layer 170 surface formed on the substrate 120 surface of one of the laminates 100D, and dried to form a phosphor layer 110 that had not been irradiated with ionizing radiation. Next, the phosphor layer 110 that had not been irradiated with ionizing radiation and the other laminate 100D were laminated so that their substrates 120 faced each other, and then ultraviolet light was irradiated to laminate the two laminates 100D together with the phosphor layer 110 having a thickness of 30 μm interposed therebetween, thereby producing the wavelength conversion sheet 200D shown in FIG.

[0276] <Phosphor Dispersion> In a glove box purged with nitrogen so that the oxygen concentration was 300 ppm or less, quantum dots and amino-modified silicone were mixed in the composition ratio shown below, and stirred with a magnetic stirrer for 4 hours while heating in a water bath at 90° C. The mixture was then filtered through a polypropylene filter with a pore size of 0.2 μm to obtain a CdSe / ZnS core-shell quantum dot dispersion. Quantum dots 0.9 parts by mass (emission peak: 540 nm, manufactured by Sigma-Aldrich) Quantum dots 0.9 parts by mass (emission peak: 630 nm, manufactured by Sigma-Aldrich) Amino-modified silicone 99 parts by mass (GP-344, manufactured by Genesee, viscosity: 670 mPa s) <Phosphor coating liquid> Polyfunctional acrylate compound 58.11 parts by mass (ethoxylated bisphenol A diacrylate; trade name "ABE-300" from Shin-Nakamura Chemical Co., Ltd.) Polyfunctional thiol compound 38.74 parts by mass (pentaerythritol tetrakis(3-mercaptopropionate); trade name "PEMP" from SC Organic Chemicals) Photopolymerization initiator 0.5 parts by mass (trade name "Omnirad TPO H" from IGM Resins B.V.) 1.61 parts by mass of the above phosphor dispersion liquid; 0.79 parts by mass of acetic acid; 0.25 parts by mass of titanium oxide (trade name "Typure R-706" by Chemours Corporation; particle size 0.36 μm)

[0277] Similarly, wavelength conversion sheets using the barrier films of Examples 2 to 4 and Comparative Examples 1 to 10 were produced in place of the barrier film 130 of Example 1. After production, the wavelength conversion sheets were wound into a roll.

[0278] Each wavelength conversion sheet obtained above was cut into a width of 100 mm and a length of 100 mm to obtain an evaluation sample. The spectral radiance of the evaluation sample was measured using a spectroradiometer SR-LEDW (Topcon Corporation). The peak top luminances near wavelengths of 449 nm, 535 nm, and 627 nm were defined as blue, green, and red luminances, respectively. The spectroradiometer was installed at the top, and a DBEF (Dual Brightness Enhancement Film), a BEF (Brightness Enhancement Film), an evaluation sample, a diffuser, and a blue LED light source were installed in this order below the objective lens of the spectroradiometer, and the spectral radiance was measured. The measurement angle was 0.1°.

[0279] The evaluation sample measured above was placed in a thermo-hygrostat at 60°C and 90% RH for 1000 hours to undergo a moist heat test, after which the luminance was measured in the same manner as above. Subsequently, the luminance maintenance rate of the evaluation sample was calculated according to the following formula. The results are shown in Table 5. Luminance maintenance factor (535 nm) = (Ga / Ba) / (Gb / Bb) x 100 (%) Luminance maintenance factor (627 nm) = (Ra / Ba) / (Rb / Bb) x 100 (%) Ba: Emission intensity (luminance) at the peak top near 449 nm after moist heat test Ga: Emission intensity (luminance) at the peak top near 535 nm after moist heat test Ra: Emission intensity (luminance) at the peak top near 627 nm after moist heat test Bb: Emission intensity (luminance) at the peak top near 449 nm before moist heat test Gb: Emission intensity (luminance) at the peak top near 535 nm before moist heat test Rb: Emission intensity (luminance) at the peak top near 627 nm before moist heat test

[0280] <Evaluation of the Presence of Black Lines> Each wavelength conversion sheet obtained above was cut into a size of 100 mm wide and 100 mm long to obtain an evaluation sample. 100 samples were taken from the core side of the roll to the outer side of the roll so that the sampling positions were not biased. The samples were placed in a constant temperature and humidity chamber at 30°C and 90% RH and left to stand for 1000 hours to perform a humidity test.

[0281] A backlight was prepared, equipped with a direct-type blue LED having an emission center wavelength of 450 nm and a full width at half maximum of 20 nm as a light source. A light diffusion plate, a wavelength conversion sheet including a quantum dot-containing layer, a prism sheet, and a reflective polarizer (brightness enhancement film, manufactured by 3M, DBEF (registered trademark)) were arranged in this order on the light output side of the backlight light source. A reflective sheet was also arranged on the side opposite the light output side of the light source.

[0282] The wavelength conversion sheet after the wet heat test was incorporated into the above backlight, and the presence or absence of black lines was visually evaluated with n = 100. The results are shown in Table 5.

[0283]

[0284] As can be seen from Tables 4 and 5, the laminates using the barrier films according to the present embodiment, in which the peak top ratio P obtained from the XAFS spectrum is 0.70 or more and less than 1.05, have high luminance maintenance ratios and do not produce black lines when used in wavelength conversion sheets.

[0285] DESCRIPTION OF SYMBOLS 100A Barrier film 100B to 100D Laminate 110 Phosphor layer 111 Sealing resin 112 Phosphor 1, 120 Base material 131b First vapor-deposited film 131a First covering layer 132b Second vapor-deposited film 132a Second covering layer 140 Pressure-sensitive adhesive layer or adhesive layer 150 Support 160 Matte layer 161 Resin 162 Particles 170 Pressure-sensitive adhesive layer or adhesive layer 200B, 200D Wavelength conversion sheet 300A, 300B Display device 310, 380 Light source unit 320 Reflection sheet 330 Light guide plate 340 Prism sheet 350 Polarized light selective reflection sheet 360 Liquid crystal panel (LCD panel) 370 Diffusion plate 10 Film-forming device P Plasma X Rotation axis 11A 1. Substrate transport mechanism 11B Plasma pretreatment mechanism 11C Film formation mechanism 12 Decompression chamber 12A Substrate transport chamber 12B Plasma pretreatment chamber 12C Film formation chamber 13 Unwinding roller 14a-d Guide roll 15 Winding roller 20 Pretreatment roller 21 Electrode unit 23 Magnetic field forming unit 23a First surface 23b Second surface 231 First magnet 231c First axial portion 232 Second magnet 232c Second axial portion 232d Connection portion 24 Evaporation mechanism 24b Boat 25 Film formation roller 31 Power supply wiring 32 Power source 35a-35c Partition wall 50 Plasma supply mechanism 51 Hollow cathode 61 Vapor deposition material supply unit 63 Aluminum vapor

Claims

1. A barrier film comprising a resin substrate, a first aluminum oxide vapor deposition film, a first coating layer, a second aluminum oxide vapor deposition film, and a second coating layer laminated in this order, wherein each of the first coating layer and the second coating layer is a cured product of a resin composition containing an alkoxysilane and a hydroxyl group-containing water-soluble resin, and wherein the first aluminum oxide vapor deposition film and the second aluminum oxide vapor deposition film have a vapor deposition film peak top ratio P, defined as follows, of 0.70 or more and less than 1.05 when X-ray absorption fine structure analysis is performed from the surface side of the second coating layer of the barrier film: P = (intensity peak top near 1572 eV) / (intensity peak top near 1566 eV).

2. The barrier film according to claim 1, wherein when the barrier film is etched from the surface side opposite to the resin substrate by time-of-flight secondary ion mass spectrometry (TOF-SIMS), the coating layer intensity ratios X, defined as follows, detected in the respective regions of the first coating layer and the second coating layer are each 0.50 or more and 1.10 or less. X=C ２ － Ionic strength / Si － Ionic Strength 3. The barrier film according to claim 1, further comprising a matte layer disposed on the side of said resin substrate opposite said first aluminum oxide vapor-deposited film.

4. A laminate in which the barrier film according to claim 1 and a support are laminated via an adhesive layer.

5. The laminate according to claim 4, wherein a matte layer is disposed on the side of said support opposite said adhesive layer.

6. A wavelength conversion sheet comprising the barrier film according to claim 3 disposed on both sides of a phosphor layer.

7. A wavelength conversion sheet in which the laminates according to claim 4 are arranged on both sides of a phosphor layer, and each of the laminates is arranged in the following order from the outermost layer side: support, resin base material, covering layer, and phosphor layer.

8. A wavelength conversion sheet in which the laminates according to claim 4 are arranged on both sides of a phosphor layer, and each of the laminates is arranged in the following order from the outermost layer side: support, covering layer, resin base material, and phosphor layer.

9. A wavelength conversion sheet in which the laminates according to claim 4 are arranged on both sides of a phosphor layer, one laminate being arranged in the order of, from the outermost layer side, the support, the resin base material, the covering layer, and the phosphor layer, and the other laminate being arranged in the order of, from the outermost layer side, the support, the covering layer, the resin base material, and the phosphor layer.

10. A backlight member comprising a light source, a light guide plate or a diffusion plate, and the wavelength conversion sheet according to claim 6.

11. A surface-mount type display device having a light guide plate, comprising a liquid crystal panel, a polarized selective reflection sheet, a prism sheet, the wavelength conversion sheet according to claim 6, the light guide plate, and a reflection sheet, laminated in that order, and a light source unit is disposed on an end face of the light guide plate.

12. A direct-type display device equipped with a diffusion plate, comprising a liquid crystal panel, a polarized light selective reflection sheet, a prism sheet, the wavelength conversion sheet according to claim 6, the diffusion plate, a light source unit, and a reflection sheet, laminated in that order.

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