Hard coating film

Abstract

The present invention provides a hard coating film that has a good appearance and is free from defects on a hard coating layer surface as a result of suppressing the occurrence of circular defects due to cissing during hard coating application and the occurrence of staining due to bleeding of a leveling agent.　This hard coating film is configured so that a hard coating layer which contains an ultraviolet curable resin, a silicone-based leveling agent, and an ultraviolet absorbing agent is layered on at least one surface of a transparent base material. The ratio A / B of a peak intensity A of 1035 cm -1 to a peak intensity B of 1450 cm -1 as measured on the surface of the hard coating layer using an infrared spectrophotometer is 1.46 or more and less than 1.49.

Description

Hard Coat Film

[0001] The present invention relates to a hard coat film used for optical members, and more particularly to a hard coat film that can be used as a protective film for panel displays such as organic electroluminescence (EL) display devices, liquid crystal display devices (LCDs), and plasma display devices, and display device components such as touch panels.

[0002] For example, the display surfaces of displays such as organic electroluminescence (EL) display devices and liquid crystal display devices (LCDs) are required to be scratch-resistant so as to prevent scratches during handling and thus reduce visibility, and therefore, a hard coat film having a hard coat layer provided on a substrate film is generally used to impart scratch resistance to the display surface.

[0003] In recent years, as displays have become thinner and lighter, the thickness of their constituent components has also been reduced. For example, there is a demand for thinner hard coat films used in polarizing plates of displays. Furthermore, when the hard coat film is used as a protective film for the surface of an organic EL display, for example, the hard coat film is required to satisfy several requirements, such as not adversely affecting the color and brightness of the display of the organic EL display, improving the durability (light resistance) of the light-emitting elements of the organic EL display, and suppressing deterioration of the display of the organic EL display.

[0004] As prior art, for example, Patent Document 1 discloses a film-forming composition containing a triazine ring-containing polymer capable of forming a thin film having a high refractive index and excellent light resistance. Also, for example, Patent Document 2 discloses a film-forming composition containing a triazine ring-containing hyperbranched polymer capable of forming a film having high transparency and high light resistance and a thickness of 1000 nm or more.

[0005] International Publication No. WO 2017 / 110810 International Publication No. WO 2013 / 094664

[0006] In order to suppress damage such as deterioration of some polymers used in organic EL displays and fading and discoloration of dyes, it is necessary to sufficiently reduce the light transmittance at wavelengths in the near-ultraviolet region, for example, at 380 nm. Furthermore, in order to improve the durability (light resistance) of light-emitting elements in recent organic EL displays, it is necessary to sufficiently reduce the light transmittance at, for example, 410 nm to protect the light-emitting elements. However, films obtained from the film-forming compositions disclosed in the above-mentioned Patent Documents 1 and 2 have very high light transmittance at, for example, 380 nm and 410 nm, and are therefore unable to solve problems such as suppressing damage such as deterioration of some polymers used in the above-mentioned organic EL displays and fading and discoloration of dyes, and improving the durability (light resistance) of light-emitting elements in organic EL displays.

[0007] In order to reduce the light transmittance in the near-ultraviolet wavelength range, it is effective to use a near-ultraviolet absorber such as a sesamol-type benzotriazole-based ultraviolet absorber. However, when the above-mentioned near-ultraviolet absorber is added to a hard coat paint, the surface tension increases, which makes it easier for cissing to occur during coating, and many circular defects are formed on the surface of the coated hard coat layer.

[0008] Addition of a leveling agent is effective in adjusting the surface tension of hard coat paints. Furthermore, due to cost and environmental impact considerations, in recent years, there has been a shift from fluorine-based leveling agents to silicone-based leveling agents as the leveling agents added to hard coat paints. However, conventional silicone-based leveling agents have a higher surface tension than fluorine-based leveling agents, making them more susceptible to repelling problems. In this case, while it is possible to lower the surface tension by increasing the amount of leveling agent added, increasing the amount of leveling agent added causes bleeding, which creates a new problem of smearing on the surface of the hard coat layer after coating.

[0009] Therefore, an object of the present invention is, first, to provide a hard coat film that is free from defects on the surface of the hard coat layer and has a good appearance, by suppressing the occurrence of circular defects due to cissing during hard coat application and the occurrence of blurring due to bleeding of a leveling agent; second, to provide a hard coat film that, when used as a protective film for the surface of an organic EL display, does not adversely affect the color or brightness of the display of the organic EL display, and can improve the durability (light resistance) of the light-emitting elements of the organic EL display, thereby suppressing deterioration of the display of the organic EL display; and third, to provide a hard coat film that can maintain the above-mentioned performance even after the hard coat film has been subjected to a light resistance test.

[0010] As a result of intensive research into solving the above problems, the present inventors have found that the above problems can be solved by the invention having the following configuration. That is, the present invention has the following configuration.

[0011] (First Invention) A hard coat layer containing an ultraviolet curable resin, a silicone-based leveling agent, and an ultraviolet absorber is laminated on at least one surface of a transparent substrate, and the surface of the hard coat layer has a 1035 cm IR spectrum measured by an infrared spectrophotometer. －１ Peak intensity A and 1450 cm －１ a ratio A / B of a peak intensity B of the hard coat film to a peak intensity A of 1.46 or more and less than 1.49.

[0012] (Second Invention) The hard coat film according to the first invention, characterized in that the light reduction rate (%) at each wavelength calculated by the following formula 1 satisfies the following conditions (A) to (C): Formula 1) Light reduction rate (%) at each wavelength = (transmittance of the transparent substrate alone at that wavelength - transmittance of the hard coat film at that wavelength) / transmittance of the transparent substrate alone at that wavelength (A) The light reduction rate at a wavelength of 380 nm is 95.0% or more. (B) The light reduction rate at a wavelength of 410 nm is 70.0% or more and 90.0% or less. (C) The light reduction rate at a wavelength of 435 nm is 15.0% or less.

[0013] (Third Invention) The hard coat film according to the first or second invention, characterized in that the hard coat film has a b* value of 5.0 or less.

[0014] (Fourth Invention) In an image of the surface of the hard coat layer taken with an optical microscope at a magnification of 50 times over an area of ​​3 mm x 3 mm or more, the number of circular defects having a diameter of 30 μm or more is 1 mm or less. ２ The hard coat film according to the first or second invention, characterized in that the number of circular defects per unit area is less than 5. (Fifth Invention) The hard coat film according to the first or second invention, characterized in that in an image of the surface of the hard coat layer taken with an optical microscope at a magnification of 50x over an area of ​​3 mm x 3 mm or more, the area occupied by circular defects of 30 μm or more is less than 10%.

[0015] (6th Invention) The hard coat film according to the first or second invention, characterized in that the silicone-based leveling agent is polyether-modified polydimethylsiloxane or polyester-modified polydimethylsiloxane. (7th Invention) The hard coat film according to the first or second invention, characterized in that the blending amount of the silicone-based leveling agent is 0.3 parts by mass to 1.4 parts by mass per 100 parts by mass of the ultraviolet-curable resin of the hard coat layer.

[0016] (Eighth Invention) The hard coat film according to the first or second invention, wherein the UV absorber is a sesamol-type benzotriazole-based UV absorber. (Ninth Invention) The hard coat film according to the eighth invention, wherein the sesamol-type benzotriazole-based UV absorber has a weight-average molecular weight in the range of 15,000 to 35,000. (Tenth Invention) The hard coat film according to the first or second invention, wherein a value defined by the concentration C (mass %) of the UV absorber contained in the hard coat layer multiplied by the film thickness D (μm) of the hard coat layer is in the range of 0.65 (mass % μm) or more and 1.38 (mass % μm) or less.

[0017] (11th invention) The hard coat film is exposed to an irradiance of 500 W / m under an environment of a temperature of 63°C and a relative humidity of 50%.２ The hard coat film according to the first or second invention is characterized in that after 100 hours of irradiation with ultraviolet light (light resistance test), the light reduction rate (%) at each wavelength calculated by the following formula 1 satisfies the following conditions (D) to (F): Formula 1) Light reduction rate (%) at each wavelength = (transmittance of the transparent substrate alone at that wavelength - transmittance of the hard coat film at that wavelength) / transmittance of the transparent substrate alone at that wavelength (D) The light reduction rate at a wavelength of 380 nm is 95.0% or more. (E) The light reduction rate at a wavelength of 410 nm is 70.0% or more and 90.0% or less. (F) The light reduction rate at a wavelength of 435 nm is 15.0% or less.

[0018] (12th Invention) The hard coat film according to the first or second invention, wherein the transparent substrate is a triacetyl cellulose film, a polyethylene terephthalate film, or a cycloolefin polymer film.

[0019] According to the present invention, it is possible to provide a hard-coated film having a good appearance and free from defects on the surface of the hard-coat layer, by suppressing the occurrence of circular defects due to cissing during hard-coat application and the occurrence of bleeding due to bleeding of the leveling agent. Furthermore, according to the present invention, it is possible to provide a hard-coated film that, when used as a protective film for the surface of an organic EL display, does not adversely affect the color or brightness of the display of the organic EL display, and can improve the durability (light resistance) of the light-emitting element of the organic EL display, thereby suppressing deterioration of the display of the organic EL display. Furthermore, according to the present invention, it is possible to provide a hard-coated film that can maintain the above-mentioned performance even after the hard-coated film is subjected to a light resistance test.

[0020] Hereinafter, embodiments for carrying out the present invention will be described in detail, but the present invention is not limited to the following embodiments. In this specification, the expression "xx to yy" means "xx or more, yy or less" unless otherwise specified.

[0021] As described in the first aspect of the present invention, the hard coat film of the present invention has a hard coat layer containing an ultraviolet curable resin, a silicone-based leveling agent, and an ultraviolet absorber laminated on at least one surface of a transparent substrate, and the surface of the hard coat layer has a 1035 cm －１ Peak intensity A and 1450 cm －１ The hard coat film of the present invention is characterized in that the ratio A / B of the peak intensity B to the peak intensity A is 1.46 or more and less than 1.49. The structure of the hard coat film of the present invention will be described in detail below.

[0022] [Transparent Substrate] First, the transparent substrate of the hard coat film will be described. A transparent film substrate is typically used as the substrate to be coated for the hard coat film of the present invention. The transparent film substrate used in the present invention is not particularly limited as long as it is transparent, and examples thereof include resin films made of acrylic resins, triacetyl cellulose, polyethylene terephthalate, cycloolefin polymers, polycarbonate, polyethylene naphthalate, polyethylene, polytrimethylene terephthalate, polypropylene, polybutylene terephthalate, polybutylene naphthalate, polystyrene, polymethyl methacrylate, polystyrene glycidyl methacrylate, aromatic polyimides, alicyclic polyimides, polyamideimides, and mixtures thereof. Here, "transparency" refers to a total light transmittance of 80% or more, measured in accordance with JIS-K7136.

[0023] In the present invention, from the viewpoint of transparency, optical properties and versatility in the optical film for display, among these film substrates, triacetyl cellulose film, polyethylene terephthalate film, cycloolefin polymer film and the like are particularly suitable.

[0024] In the present invention, the thickness of the transparent substrate is appropriately selected depending on the application, but from the viewpoint of the demand for thinner hard coat films in response to thinner and lighter displays, it is preferably 50 μm or less, particularly preferably 30 μm or less, while from the viewpoint of mechanical strength, handleability, etc., it is preferably 10 μm or more.

[0025] [Hard Coat Layer] Next, the hard coat layer of the hard coat film will be described. In the present invention, the hard coat layer contains at least an ultraviolet curable resin, a silicone leveling agent, and an ultraviolet absorber. In the present invention, it is preferable to use an ultraviolet curable resin as the resin contained in the hard coat layer, since it particularly imparts surface hardness (pencil hardness, scratch resistance) to the hard coat layer and can adjust the degree of crosslinking by the amount of ultraviolet light exposure, making it possible to adjust the surface hardness of the hard coat layer.

[0026] The ultraviolet curable resin used in the present invention is not particularly limited as long as it is a transparent resin that can be cured by irradiating ultraviolet (UV) rays, but it is preferable to use a UV-curable polyfunctional acrylate having three or more (meth)acryloyloxy groups in one molecule in order to improve coating hardness and form a three-dimensional crosslinked structure of the hard coat layer.Specific examples of the UV-curable polyfunctional acrylate having three or more (meth)acryloyloxy groups in one molecule include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, trimethylolpropane ethoxy triacrylate, glycerin propoxy triacrylate, ditrimethylolpropane tetraacrylate, etc. The polyfunctional acrylate may be used alone or in combination of two or more kinds.

[0027] Furthermore, the UV-curable resin used in the hard coat layer is preferably a monomer, oligomer, or polymer having a weight-average molecular weight in the range of 500 to 3600, more preferably 500 to 3000, and even more preferably 500 to 2400. If the weight-average molecular weight is less than 500, curing shrinkage upon curing by UV irradiation is significant, resulting in increased curling of the hard coat film toward the hard coat layer, which can cause problems in subsequent processing steps and poor processability. Furthermore, if the weight-average molecular weight exceeds 3600, the flexibility of the hard coat layer is increased, but the hardness is insufficient, making this unsuitable. The weight-average molecular weight in this invention is the average molecular weight obtained by gel permeation chromatography (GPC) analysis in terms of standard polystyrene.

[0028] Furthermore, when the weight-average molecular weight of the ultraviolet-curable resin used in the hard coat layer is less than 1500, the number of functional groups in one molecule is preferably 3 or more and less than 10. Furthermore, when the weight-average molecular weight of the ultraviolet-curable resin is 1500 or more, the number of functional groups in one molecule is preferably 3 or more and less than 20. Within the above ranges, curling can be suppressed and appropriate processability can be maintained.

[0029] In addition to the ultraviolet-curable resins described above, the resin contained in the hard coat layer may be a thermoplastic resin such as polyethylene, polypropylene, polystyrene, polycarbonate, polyester, acrylic, styrene-acrylic, or cellulose, or a thermosetting resin such as a phenolic resin, urea resin, unsaturated polyester, epoxy, or silicone resin, within a range that does not impair the hardness and scratch resistance of the hard coat layer.

[0030] In the present invention, the hard coat layer contains an ultraviolet absorber in addition to the ultraviolet-curable resin. In the present invention, a sesamol-type benzotriazole ultraviolet absorber (hereinafter sometimes referred to as the "ultraviolet absorber of the present invention"), which has high wavelength absorption in the near-ultraviolet region, can be preferably used.

[0031] The ultraviolet absorber of the present invention is obtained by reacting a sesamol-type benzotriazole monomer with, for example, an acrylate resin component to form a polymer.

[0032] Here, the sesamol-type benzotriazole monomer is, for example, represented by the following general formula (I), and is a derivative of a compound in which sesamol is bonded to the nitrogen atom at the 2-position of the benzotriazole ring.

[0033]

[0034] In the above formula, R １ represents a hydrogen atom or a methyl group. ２represents a linear or branched alkylene group having 1 to 6 carbon atoms, or a linear or branched oxyalkylene group having 1 to 6 carbon atoms. Specific examples of the sesamol-type benzotriazole monomer represented by the general formula (I) include 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]ethyl methacrylate, 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]ethyl acrylate, 3-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]propyl ... propyl methacrylate, 3-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]propyl acrylate, 4-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]butyl methacrylate, 4-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]butyl acrylate, 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]butyl 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yloxy]ethyl acrylate, 2-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl methacrylate, 2-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl methacrylate, 4-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl acrylate, 4-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]butyl methacrylate, 4-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]butyl acrylate, 2-(methacryloyloxy)ethyl-2-(6-hydroxybenzo[1,Examples of such esters include 2-(acryloyloxy)ethyl-2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate, 2-(acryloyloxy)ethyl-2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate, 4-(methacryloyloxy)butyl-2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate, and 4-(acryloyloxy)butyl-2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate.

[0035] The ultraviolet absorber of the present invention can be obtained by polymerizing the sesamol-type benzotriazole monomer with other monomer components (e.g., acrylate resin components such as methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, isopropyl(meth)acrylate, butyl(meth)acrylate, isobutyl(meth)acrylate, t-butyl(meth)acrylate, octyl(meth)acrylate, and nonyl(meth)acrylate). The polymerization method can be a conventionally known solution polymerization method, emulsion polymerization method, suspension polymerization method, bulk polymerization method, or the like.

[0036] In the present invention, it is particularly preferable to use a sesamol-type benzotriazole-based UV absorber having a weight-average molecular weight in the range of 15,000 to 35,000. In contrast, when a sesamol-type benzotriazole-based UV absorber having a weight-average molecular weight of less than 15,000 is used, the light transmittance at 410 nm cannot be sufficiently reduced, resulting in a problem of degradation of the display of the organic EL display. Furthermore, when a sesamol-type benzotriazole-based UV absorber having a weight-average molecular weight exceeding 35,000 is used, the performance cannot be maintained even after a light resistance test at a wavelength of 410 nm, resulting in a problem of degradation of the display of the organic EL display and an inability to achieve improved durability (light resistance) of the light-emitting element. The weight-average molecular weight of the sesamol-type benzotriazole-based UV absorber is the average molecular weight obtained by gel permeation chromatography (GPC) analysis in terms of standard polystyrene.

[0037] The ultraviolet absorbers of the present invention may be used alone or in combination of two or more thereof. Furthermore, other benzotriazole-based ultraviolet absorbers, hydroxyphenyltriazine-based ultraviolet absorbers, etc. may also be used in combination within the range that does not impair the effects of the present invention.

[0038] In the hard coat film of the present invention, the hard coat layer contains the above-mentioned ultraviolet absorber of the present invention, so that the spectral characteristics (light reduction rates at wavelengths of 380 nm, 410 nm, and 435 nm) can satisfy the above conditions (A) to (C).

[0039] As described below, in the present invention, the thickness of the hard coat layer containing the UV absorber of the present invention is preferably more than 2.0 μm and less than 6.0 μm, and particularly preferably in the range of 3.0 μm to 5.0 μm. When the thickness of the hard coat layer is more than 2.0 μm and less than 6.0 μm, the blending amount of the UV absorber of the present invention is preferably in the range of 20 to 60 parts by mass per 100 parts by mass of the UV-curable resin of the hard coat layer. If the blending amount of the UV absorber of the present invention is less than 20 parts by mass, the spectral characteristics of the present invention cannot be fully satisfied within the thickness range of more than 2.0 μm and less than 6.0 μm. On the other hand, if the blending amount of the UV absorber of the present invention exceeds 60 parts by mass, the proportion of the UV-curable resin in the hard coat layer decreases, which may result in a decrease in adhesion of the hard coat layer to the film substrate or a decrease in hardness of the hard coat layer, and is therefore unsuitable. When the thickness of the hard coat layer is in the range of 3.0 μm to 5.0 μm, the blending amount of the ultraviolet absorber of the present invention is preferably in the range of 30 parts by mass to 50 parts by mass per 100 parts by mass of the ultraviolet curable resin of the hard coat layer.

[0040] In the present invention, it is particularly preferable to adjust the relationship between the concentration of the ultraviolet absorber contained in the hard coat layer (C (mass%)) and the film thickness of the hard coat layer (D (μm)) so that the relationship between the concentration of the ultraviolet absorber contained in the hard coat layer and the film thickness of the hard coat layer is in the range of 0.65 (mass% μm)≦C×D≦1.38 (mass% μm). That is, it is preferable to adjust the relationship between the concentration of the ultraviolet absorber contained in the hard coat layer (C (mass%)) and the film thickness of the hard coat layer (D (μm)) so that the value defined by the concentration of the ultraviolet absorber contained in the hard coat layer (C (mass%))×the film thickness of the hard coat layer (D (μm)) is in the range of 0.65 (mass% μm) or more and 1.38 (mass% μm) or less.

[0041] If the C×D value is less than 0.65 (mass% μm), the light transmittance at 410 nm cannot be sufficiently reduced, resulting in a problem of deterioration of the display of the organic EL display. Furthermore, if the C×D value exceeds 1.38 (mass% μm), the adhesion of the hard coat layer to the film substrate decreases, which is undesirable. Furthermore, using an excessive amount of UV absorber is undesirable because bleeding occurs.

[0042] The hard coat film of the present invention further contains a silicone-based leveling agent in the hard coat layer. The silicone-based leveling agent used in the present invention is preferably a low-molecular-weight siloxane that is not a resin (polymer), and specifically, for example, polyether-modified polydimethylsiloxane or polyester-modified polydimethylsiloxane is preferably used. The amount of the silicone-based leveling agent blended is preferably 0.3 to 1.4 parts by mass per 100 parts by mass of the ultraviolet-curable resin in the hard coat layer.

[0043] As will be described in detail later, in the present invention, the hard coat layer contains a silicone-based leveling agent, and the surface of the hard coat layer is measured with an infrared spectrophotometer to obtain a level of 1035 cm －１ Peak intensity A and 1450 cm －１ It is important that the ratio A / B of the peak intensity B to the peak intensity A is 1.46 or more and less than 1.49.

[0044] Furthermore, it is possible to further improve the surface hardness (scratch resistance) by incorporating inorganic oxide fine particles into the hard coat layer. In this case, the average particle diameter of the inorganic oxide fine particles is preferably in the range of 5 to 50 nm, more preferably in the range of 10 to 40 nm. If the average particle diameter is less than 5 nm, it is difficult to obtain sufficient surface hardness. On the other hand, if the average particle diameter exceeds 50 nm, the gloss and transparency of the hard coat layer are likely to decrease, and flexibility may also decrease.

[0045] In the present invention, examples of the inorganic oxide fine particles include alumina, silica, etc. Among these, alumina, which is mainly composed of aluminum, is particularly suitable because it has high hardness and can be effective with a smaller amount added than silica.

[0046] In the present invention, the content of inorganic oxide fine particles is preferably 0.1 to 10.0 parts by mass relative to 100 parts by mass of the ultraviolet-curable resin of the hard coat layer. If the content of inorganic oxide fine particles is less than 0.1 part by mass, it is difficult to obtain an effect of improving surface hardness (scratch resistance). On the other hand, if the content exceeds 10.0 parts by mass, haze increases, which is undesirable.

[0047] The hard coating material for forming the hard coating layer may contain a photopolymerization initiator, such as commercially available acetophenones such as IRGACURE 651 and IRGACURE 184 (both trade names: manufactured by BASF Corporation) or benzophenones such as IRGACURE 500 (trade name: manufactured by BASF Corporation).

[0048] Other additives that may be added to the hard coat layer, if necessary, include dyes (e.g., cyanine dyes), antifoaming agents, surface tension adjusters, antifouling agents, antioxidants, antistatic agents, light stabilizers, and the like, within the scope of not impairing the effects of the present invention.

[0049] The hard coat layer is formed by applying a hard coat coating material prepared by dissolving and dispersing the above-mentioned UV-curable resin, UV absorber, silicone leveling agent, photopolymerization initiator, and other additives in a suitable solvent onto the transparent substrate, drying the coating, and then curing the coating by UV irradiation. The solvent can be appropriately selected depending on the solubility of the resin to be blended, as long as it can uniformly dissolve or disperse at least the solid components (resin, UV absorber, silicone leveling agent, photopolymerization initiator, and other additives). Examples of such solvents include aromatic solvents such as toluene, xylene, and n-heptane; aliphatic solvents such as cyclohexane, methylcyclohexane, and ethylcyclohexane; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and methyl lactate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; and alcohol solvents such as methanol, ethanol, isopropyl alcohol, and n-propyl alcohol. These solvents can be used alone or in combination.

[0050] The method for applying the hard coating paint to form the hard coating layer is not particularly limited, but the hard coating paint can be applied by a known coating method such as gravure coating, microgravure coating, fountain bar coating, slide die coating, slot die coating, screen printing, or spray coating, and then dried at a temperature of usually about 50 to 120°C.

[0051] The amount of ultraviolet (UV) irradiation after the formation of the hard coat layer coating film may be any amount necessary to provide the hard coat layer with sufficient hardness, and can be appropriately set depending on the type of ultraviolet curable resin, etc.

[0052] In the present invention, the thickness of the hard coat layer (coating film thickness) is, for example, preferably more than 2.0 μm and less than 6.0 μm, more preferably in the range of 3.0 μm to 5.0 μm. A hard coat layer thickness of less than 2.0 μm is undesirable because the required hardness (e.g., scratch resistance) decreases. On the other hand, a hard coat layer thickness of 6.0 μm or more is undesirable because it is prone to severe curling, reducing handleability in the manufacturing process and the like, and also from the viewpoint of thinning the hard coat film.

[0053] As described above, in the present invention, the film thickness of the hard coat layer may be adjusted in relation to the concentration of the ultraviolet absorber so that the relationship between the concentration C (mass %) of the ultraviolet absorber contained in the hard coat layer and the film thickness D (μm) of the hard coat layer is in the range of 0.65 (mass % μm)≦C×D≦1.38 (mass % μm), that is, so that the value defined by the concentration C (mass %) of the ultraviolet absorber contained in the hard coat layer×the film thickness D (μm) of the hard coat layer is in the range of 0.65 (mass % μm) or more and 1.38 (mass % μm) or less.

[0054] The hard coat film of the present invention is obtained by laminating the above-mentioned hard coat layer on at least one surface of a transparent substrate. For example, when a cycloolefin polymer film is used as the transparent substrate, it is also preferable to provide an easy-adhesion layer between the transparent substrate and the hard coat layer in order to improve the adhesion of the hard coat layer.

[0055] The resin used in the easy-adhesion layer is not particularly limited as long as it is a resin that forms a coating. For example, from the viewpoint of adhesion to the transparent substrate film (cycloolefin film), polyolefin-based resins, acrylic resins such as styrene-acrylic resins and methyl methacrylate resins, epoxy-based resins, isocyanate-based resins, cellulose-based resins, or mixtures of two or more of these resins can be preferably used.

[0056] The coating thickness of the easy-adhesion layer is not particularly limited, but is preferably in the range of 0.1 μm to 5.0 μm, which is a range that does not adversely affect the adhesion between the substrate film and the hard coat layer, or the pencil hardness of the hard coat layer.

[0057] As described above, the hard coat film of the present invention comprises a transparent substrate and a hard coat layer containing an ultraviolet curable resin, a silicone leveling agent, and an ultraviolet absorber laminated on at least one surface of the transparent substrate.

[0058] The hard coat film of the present invention has a hard coat layer surface having a 1035 cm －１ Peak intensity A and 1450 cm －１ The ratio A / B of the peak intensity B of the hard coat layer to the peak intensity A of the hard coat layer satisfies the range of the present invention, and thus it is possible to suppress both the occurrence of circular defects due to cissing during application of the hard coat layer and the occurrence of blurring due to bleeding of the leveling agent.

[0059] Here, the 1035 cm －１ The peak intensity A at 1450 cm is due to the stretching vibration of Si—O and residues that contribute to suppressing cissing in the siloxane-based leveling agent such as the polyether-modified polydimethylsiloxane and polyester-modified polydimethylsiloxane. －１ The peak intensity B is due to the C—H bending vibration and the main skeleton of the ultraviolet curable resin, which does not contribute to cissing suppression. －１ Peak intensity A and 1450 cm －１ The ratio A / B of the peak intensity B of the hard coat paint is the ratio of residues that contribute to suppressing cissing in the hard coat paint, and suggests that molecular motion due to Si-O stretching motion in particular is the cause of the bleeding and cissing suppression effect.

[0060] The evaluation criteria for the occurrence of circular defects are, for example, the number of circular defects of 30 μm or more in diameter exceeding 1 mm in an image of an area of ​​3 mm×3 mm or more of the surface of the hard coat layer photographed with an optical microscope at a magnification of 50 times. ２In addition, in an image of the surface of the hard coat layer taken with an optical microscope at a magnification of 50 times over an area of ​​3 mm × 3 mm or more, if the area occupied by circular defects of 30 μm or more in diameter is less than 10%, the test is also acceptable.

[0061] If the ratio A / B is less than 1.46, circular defects are likely to occur, and if the ratio A / B is 1.49 or more, bleeding due to bleeding of the leveling agent is likely to occur. In either case, if the ratio A / B is outside the range of the present invention, it is not possible to suppress the occurrence of circular defects due to cissing during hard coat application, or the occurrence of bleeding due to bleeding of the leveling agent.

[0062] The hard coat film of the present invention is further characterized by satisfying the following optical properties. That is, the hard coat film of the present invention is characterized in that the light reduction rate (%) at each wavelength calculated by the following formula 1 satisfies the following conditions (A) to (C): Formula 1) Light reduction rate (%) at each wavelength = (transmittance of the transparent substrate alone at that wavelength - transmittance of the hard coat film at that wavelength) / transmittance of the transparent substrate alone at that wavelength (A) The light reduction rate at a wavelength of 380 nm is 95.0% or more. (B) The light reduction rate at a wavelength of 410 nm is 70.0% or more and 90.0% or less. (C) The light reduction rate at a wavelength of 435 nm is 15.0% or less. Specific methods for measuring the light transmittance at each of the above wavelengths will be explained in the examples below.

[0063] The hard coat film of the present invention is characterized in that the b* value is 5.0 or less, and particularly preferably 4.3 or less.

[0064] As a result, the hard coat film of the present invention can suppress the b* value, which is an index of yellowness, to 5.0 or less, without adversely affecting the displayed color of the organic EL display, and can achieve a light reduction rate of 95% or more at wavelengths typified by 380 nm, which are responsible for the deterioration of some polymers used in organic EL displays and damage such as fading and discoloration of dyes, thereby suppressing damage such as deterioration of these polymers and fading and discoloration of dyes.

[0065] Furthermore, in order to improve the durability (light resistance) of light-emitting elements in recent organic EL displays, it has been necessary to sufficiently reduce the light transmittance at wavelengths such as 410 nm to protect the light-emitting elements. The hard coat film of the present invention can achieve a light reduction rate of 70.0% to 90.0% at a wavelength of 410 nm, thereby improving the durability (light resistance) of the light-emitting elements in recent organic EL displays. Note that if the light reduction rate at a wavelength of 410 nm exceeds 90.0%, the b* value increases, causing a yellowish tint and affecting the color of the display of the organic EL display. In addition, it is necessary to minimize the light reduction rate at wavelengths such as 435 nm in the visible light range in order to ensure the display brightness of the organic EL display. The hard coat film of the present invention can suppress the light reduction rate at a wavelength of 435 nm in the visible light range to 15.0% or less, thereby not adversely affecting the display brightness of the organic EL display.

[0066] Furthermore, the hard coat film of the present invention has a radiant illuminance of 500 W / m2 when exposed to an environment of a temperature of 63°C and a relative humidity of 50%. ２and after 100 hours of irradiation with ultraviolet light (light resistance test), the light reduction rate (%) at each wavelength calculated by the following formula 1 satisfies the following conditions (D) to (F): Formula 1) Light reduction rate (%) at each wavelength = (transmittance of the transparent substrate alone at that wavelength - transmittance of the hard coat film at that wavelength) / transmittance of the transparent substrate alone at that wavelength (D) The light reduction rate at a wavelength of 380 nm is 95.0% or more. (E) The light reduction rate at a wavelength of 410 nm is 70.0% or more and 90.0% or less. (F) The light reduction rate at a wavelength of 435 nm is 15.0% or less. Details of the light resistance test will be described later in the description of the examples.

[0067] For the purpose, the light ray reduction rate at each of the above-mentioned wavelengths must maintain its optical performance even after a light resistance test at wavelengths such as 380 nm, which causes damage such as deterioration of some polymers and fading or discoloration of dyes, and at wavelengths such as 410 nm, which contributes to protecting the light-emitting elements of recent organic EL displays. The hard coat film of the present invention can maintain its light ray reduction rate at wavelengths of 380 nm and 410 nm even after a light resistance test, thereby suppressing deterioration of the display of the organic EL display. Furthermore, the hard coat film of the present invention can also suppress the light ray reduction rate at a wavelength of 435 nm in the visible light region even after a light resistance test, thereby maintaining the display brightness of the organic EL display.

[0068] In the present invention, a UV-curable resin, a silicone-based leveling agent, and a UV absorber are used in combination, and the surface of the hard coat layer is measured with an infrared spectrophotometer to obtain a 1035 cm －１ Peak intensity A and 1450 cm －１ By providing a hard coat layer in which the ratio A / B of the peak intensity B of the hard coat layer is 1.46 or more and less than 1.49, problems of cissing and bleeding usually occur when a silicone-based leveling agent is used. However, according to the present invention, it is possible to simultaneously solve both of the problems of the occurrence of circular defects due to cissing during hard coat application and the occurrence of smearing due to bleeding of the leveling agent.

[0069] In the present invention, a silicone-based leveling agent and an ultraviolet absorber are used in combination in the hard coat layer. In this case, it is preferable that the value defined by the concentration C (mass%) of the ultraviolet absorber contained in the hard coat layer x the film thickness D (μm) of the hard coat layer is in the range of 0.65 (mass% μm) or more and 1.38 (mass% μm) or less. In the present invention, it is particularly preferable to use a sesamol-type benzotriazole-based ultraviolet absorber in combination with a silicone-based leveling agent (especially a low-molecular-weight siloxane such as polyether-modified polydimethylsiloxane or polyester-modified polydimethylsiloxane).

[0070] As described above in detail, according to the present invention, the occurrence of circular defects due to repelling during hard coat application and the occurrence of smearing due to bleeding of the leveling agent can be suppressed, thereby obtaining a hard coat film with a good appearance and no defects on the hard coat layer surface. Furthermore, according to the present invention, when used as a protective film for the surface of an organic EL display, a hard coat film can be obtained that does not adversely affect the color or brightness of the display of the organic EL display, and can improve the durability (light resistance) of the light-emitting element of the organic EL display, thereby suppressing deterioration of the display of the organic EL display. Furthermore, according to the present invention, a hard coat film can be obtained that maintains the above-mentioned performance even after the hard coat film is subjected to a light resistance test.

[0071] Next, the embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. In the following description, "parts" means parts by mass unless otherwise specified, and "%" means % by mass unless otherwise specified.

[0072] Example 1 Preparation of Hard Coat Layer-Forming Coating Fluid 94 parts of an acrylate-based ultraviolet curable resin coating material containing the sesamol-type benzotriazole-based ultraviolet absorber of the present invention (HFC-UVA-13 (trade name); manufactured by Harima Chemicals Co., Ltd.; weight average molecular weight of the sesamol-type benzotriazole-based ultraviolet absorber: 22,000) as a base material was blended with 5 parts of Irgacure 184 (photopolymerization initiator; manufactured by BASF) and 1 part of polyester-modified polydimethylsiloxane (silicone-based leveling agent; BYK-313; manufactured by BYK Co., Ltd.), and diluted with toluene / propylene glycol monomethyl ether acetate = 15 / 85 (parts by weight) to prepare a hard coat layer-forming coating fluid (hereinafter also referred to as "hard coat coating material") with a final solids concentration of 30%.

[0073] [Preparation of Hard Coat Film] The above hard coat coating material was applied to one side of a 25 μm-thick triacetyl cellulose film, TJ25UL (manufactured by Fujifilm Corporation), using a bar coater, and then dried with hot air in a drying oven at 80° C. for 1 minute to form a coating layer with a coating thickness of 3.0 μm. This was then irradiated with a UV irradiation device set at a height of 60 mm from the coated surface at a UV irradiation dose of 100 mJ / cm. ２ The hard coat film was cured by irradiation with ultraviolet light of 1000 W at ...

[0074] (Example 2) A hard coat coating material prepared in the same manner as in Example 1 was used, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 0.7 parts, and a hard coat film of Example 2 was produced in the same manner as in Example 1.

[0075] (Example 3) A hard coat coating material prepared in the same manner as in Example 1 was used, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 0.5 parts, and a hard coat film of Example 3 was produced in the same manner as in Example 1.

[0076] Example 4 A hard coat coating material prepared in the same manner as in Example 1 was used, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 0.4 parts, and a hard coat film of Example 4 was produced in the same manner as in Example 1.

[0077] Example 5 A hard coat coating material prepared in the same manner as in Example 1 was used, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 0.3 parts, and a hard coat film of Example 5 was produced in the same manner as in Example 1.

[0078] Comparative Example 1 A hard coat coating material prepared in the same manner as in Example 1 was used, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 1.5 parts, and a hard coat film of Comparative Example 1 was produced in the same manner as in Example 1.

[0079] Comparative Example 2 A hard coat coating material prepared in the same manner as in Example 1 was used, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 0.2 parts, and a hard coat film of Comparative Example 2 was produced in the same manner as in Example 1.

[0080] Comparative Example 3 A hard coat film of Comparative Example 3 was produced in the same manner as in Example 1, except that the blending amount of the polyester-modified polydimethylsiloxane (silicone-based leveling agent, BYK-313; manufactured by BYK Corporation) was 0.1 parts, using a hard coat paint prepared in the same manner as in Example 1.

[0081] (Comparative Example 4) A hard coat film of Comparative Example 4 was produced in the same manner as in Example 1, using a hard coat coating material prepared in the same manner as in Example 1, except that the sesamol-type benzotriazole-based ultraviolet absorber was not added.

[0082] <Evaluation> Each of the hard coat films of the Examples and Comparative Examples prepared as described above was evaluated for the following items. The results are summarized in Table 1.

[0083] <Measurement of the hard coat layer surface with an infrared spectrophotometer> Measurement was performed using an infrared spectrophotometer (Spectrum 100, manufactured by PerkinElmer) by the ATR method. －１ Peak intensity A and 1450 cm －１ The ratio A / B of the peak intensity B of the peak intensity A to the peak intensity B of the peak intensity B was calculated.

[0084] <Evaluation of bleeding occurrence> The appearance of the surface of the hard coat layer was observed to check for bleeding, and the absence of bleeding was evaluated as ◯, and the presence of bleeding was evaluated as ×.

[0085] <Defect Evaluation> The surface of the hard coat layer was observed with an optical microscope (VHX-5000, manufactured by Keyence Corporation), and an image of an area of ​​3 mm x 3 mm or more was photographed at a magnification of 50 times. ２ The number of circular defects with a diameter of 30 μm or more per square meter was measured. The evaluation criteria were that the number of defects was less than 5, which was considered acceptable. Similarly, the surface of the hard coat layer was photographed with an optical microscope at a magnification of 50 times over an area of ​​3 mm × 3 mm or more, and the area ratio (%) of circular defects with a diameter of 30 μm or more was measured. The evaluation criteria were that the defect area ratio was less than 10%, which was considered acceptable.

[0086] <Light transmittance and light reduction rate at each wavelength> The light transmittance of the hard coat film at each wavelength (380 nm, 410 nm, 435 nm) was measured using a spectrophotometer U-3310 manufactured by Hitachi High-Technologies. The measurement was performed in the wavelength range of 250 to 800 nm at a scan speed of 600 nm / min. After measuring the light transmittance at each wavelength, the "light reduction rate (%) at each wavelength" was calculated as shown in the following formula 1. Formula 1) Light reduction rate (%) at each wavelength = (transmittance of transparent substrate (the triacetyl cellulose film) alone at that wavelength - transmittance of hard coat film at that wavelength) / transmittance of transparent substrate (the triacetyl cellulose film) alone at that wavelength

[0087] <b* Value> The b* value was measured for each of the hard coat films produced in the Examples and Comparative Examples using a spectrophotometer U-3310 manufactured by Hitachi High-Technologies Corporation.

[0088] <Lightfastness Test> Each hard coat film produced in the Examples and Comparative Examples was subjected to an accelerated lightfastness test using a Xenon Weather Ometer (conforming to JIS-K-5600-7-7 under the following conditions): Light source: Xenon arc Temperature: 63°C Relative humidity: 50% Irradiance: 50 W / m ２ Radiation time: 100 hours Rainfall cycle and time: Not set

[0089] After the light resistance test, the light transmittance and light reduction rate of the hard coat film at each wavelength were measured in the same manner as above.

[0090]

[0091] As is clear from the results in Table 1 above, the hard coat films of the examples of the present invention have a ratio A / B that satisfies the range of the present invention, and no bleeding occurs. Furthermore, there are no problems with the occurrence of circular defects (number and area), and the results are acceptable. Normally, when a silicone-based leveling agent is used, problems such as cissing and bleeding occur. However, according to the present invention, the occurrence of circular defects due to cissing during hard coat application and the occurrence of smearing due to bleeding of the leveling agent are suppressed, and a hard coat film with a good appearance and no defects on the hard coat layer surface can be obtained.

[0092] Furthermore, the hard coat film of the present invention has spectral characteristics (light reduction rates at wavelengths of 380 nm, 410 nm, and 435 nm) that satisfy the ranges of the present invention (conditions (A) to (C) above). As a result, the hard coat film of the present invention can suppress the b* value, which is an index of yellowness, to 5.0 or less, without adversely affecting the displayed color of the organic EL display, and can achieve a light reduction rate of 95% or more at a wavelength typified by 380 nm, which causes damage such as deterioration of some polymers used in organic EL displays and fading and discoloration of dyes, thereby suppressing damage such as deterioration of these polymers and fading and discoloration of dyes.

[0093] Furthermore, in order to improve the durability (light resistance) of light-emitting elements in recent organic EL displays, it has been necessary to sufficiently reduce the light transmittance at wavelengths such as 410 nm to protect the light-emitting elements. The hard coat film of the present invention can achieve a light reduction rate of 70.0% to 90.0% at a wavelength of 410 nm, thereby improving the durability (light resistance) of the light-emitting elements in recent organic EL displays. Note that if the light reduction rate at a wavelength of 410 nm exceeds 90.0%, the b* value increases, causing a yellowish tint and affecting the color of the display of the organic EL display. In addition, it is necessary to minimize the light reduction rate at wavelengths such as 435 nm in the visible light range in order to ensure the display brightness of the organic EL display. The hard coat film of the present invention can suppress the light reduction rate at a wavelength of 435 nm in the visible light range to 15.0% or less, thereby not adversely affecting the display brightness of the organic EL display.

[0094] For the purpose, the light ray reduction rate at each of the above-mentioned wavelengths must maintain its optical performance even after a light resistance test at wavelengths such as 380 nm, which causes damage such as deterioration of some polymers and fading or discoloration of dyes, and at wavelengths such as 410 nm, which contributes to protecting the light-emitting elements of recent organic EL displays. The hard coat film of the present invention can maintain its light ray reduction rate at wavelengths of 380 nm and 410 nm even after a light resistance test, thereby suppressing deterioration of the display of the organic EL display. Furthermore, the hard coat film of the present invention can also suppress the light ray reduction rate at a wavelength of 435 nm in the visible light region even after a light resistance test, thereby maintaining the display brightness of the organic EL display.

[0095] On the other hand, in the hard coat films of Comparative Examples 1 to 3, in which the ratio A / B does not satisfy the range of the present invention, bleeding occurred (Comparative Example 1) or circular defects occurred frequently (Comparative Examples 2 and 3). That is, the comparative examples were unable to solve the problem of suppressing both bleeding and circular defects. Furthermore, in the hard coat film of Comparative Example 4, which does not contain the ultraviolet absorber of the present invention, the light reduction rate at each wavelength was 0%, meaning that light was not reduced at all. In particular, the light transmittance at 410 nm could not be sufficiently reduced, resulting in a problem of deterioration of the display of the organic EL display.

Claims

1. A hard coat layer containing an ultraviolet curing resin, a silicone-based leveling agent, and an ultraviolet absorber is laminated on at least one surface of a transparent substrate, and the surface of the hard coat layer has an infrared spectrophotometer measurement of 1035 cm －１ Peak intensity A and 1450 cm －１ a ratio A / B of a peak intensity B of the hard coat film to a peak intensity A of 1.46 or more and less than 1.

49.

2. The hard coat film according to claim 1, characterized in that the light reduction rate (%) at each wavelength calculated by the following formula 1 satisfies the following conditions (A) to (C): Formula 1) Light reduction rate (%) at each wavelength = (transmittance of the transparent substrate alone at that wavelength - transmittance of the hard coat film at that wavelength) / transmittance of the transparent substrate alone at that wavelength (A) The light reduction rate at a wavelength of 380 nm is 95.0% or more. (B) The light reduction rate at a wavelength of 410 nm is 70.0% or more and 90.0% or less. (C) The light reduction rate at a wavelength of 435 nm is 15.0% or less.

3. The hard coat film according to claim 1 or 2, characterized in that the hard coat film has a b* value of 5.0 or less.

4. In an image of the surface of the hard coat layer taken with an optical microscope at a magnification of 50 times over an area of ​​3 mm x 3 mm or more, the number of circular defects with a diameter of 30 μm or more is 1 mm ２ 3. The hard coat film according to claim 1, wherein the number of particles per one particle is less than 5.

5. The hard coat film according to claim 1 or 2, characterized in that in an image of the surface of the hard coat layer taken with an optical microscope at a magnification of 50 times over an area of ​​3 mm x 3 mm or more, the area occupied by circular defects having a diameter of 30 μm or more is less than 10%.

6. The hard coat film according to claim 1 or 2, characterized in that the silicone-based leveling agent is polyether-modified polydimethylsiloxane or polyester-modified polydimethylsiloxane.

7. A hard coat film as described in claim 1 or 2, characterized in that the amount of the silicone-based leveling agent is 0.3 to 1.4 parts by mass per 100 parts by mass of the ultraviolet-curable resin of the hard coat layer.

8. The hard coat film according to claim 1 or 2, wherein the ultraviolet absorbent is a sesamol-type benzotriazole-based ultraviolet absorbent.

9. The hard coat film according to claim 8, wherein the sesamol-type benzotriazole ultraviolet absorber has a weight average molecular weight in the range of 15,000 to 35,000.

10. The hard coat film according to claim 1 or 2, characterized in that a value defined by a concentration C (mass %) of the ultraviolet absorber contained in the hard coat layer x a film thickness D (μm) of the hard coat layer is in the range of 0.65 (mass % μm) or more and 1.38 (mass % μm) or less.

11. The hard coat film is exposed to a radiant illuminance of 500 W / m2 at a temperature of 63°C and a relative humidity of 50%. ２ The hard coat film according to claim 1 or 2, characterized in that after 100 hours of irradiation with ultraviolet light (light resistance test), the light reduction rate (%) at each wavelength calculated by the following formula 1 satisfies the following conditions (D) to (F): Formula 1) Light reduction rate (%) at each wavelength = (transmittance of the transparent substrate alone at that wavelength - transmittance of the hard coat film at that wavelength) / transmittance of the transparent substrate alone at that wavelength (D) The light reduction rate at a wavelength of 380 nm is 95.0% or more. (E) The light reduction rate at a wavelength of 410 nm is 70.0% or more and 90.0% or less. (F) The light reduction rate at a wavelength of 435 nm is 15.0% or less.

12. The hard coat film according to claim 1 or 2, wherein the transparent substrate is a triacetyl cellulose film, a polyethylene terephthalate film, or a cycloolefin polymer film.

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