JP2023105806A - Transparent substrate with antireflection coating and image display device - Google Patents

Abstract

To provide a transparent substrate with antireflection coating with which a reflected glare of external light is sufficiently suppressed, and an image display device that includes this substrate.SOLUTION: The present invention relates to a transparent substrate with antireflection coating comprising a transparent substrate having two principal planes and having a diffusion layer and an antireflection coating on one principal plane of the transparent substrate in the order stated. (A) The luminous reflectance (SCI Y) on the outermost surface of the transparent substrate with antireflection coating is 1% or less; (B) the antireflection coating is of a laminate structure in which at least two dielectric layers mutually differing in refractive index are laminated; (C) the ratio SCE Y/SCI Y of the diffuse reflectance (SCI Y) on the outermost surface of the transparent substrate with antireflection coating to the luminous reflectance (SCI Y) on the outermost surface of the transparent substrate with antireflection coating is 0.15 or greater.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a transparent substrate with an antireflection film and an image display device having the same.

2. Description of the Related Art In recent years, from the viewpoint of aesthetics, a method of placing a transparent substrate such as a cover glass on the front surface of an image display device such as a liquid crystal display (LCD) has been used. However, one of the problems with the transparent substrate is reflection due to reflection of external light.

BACKGROUND ART Conventionally, a transparent substrate provided with an antireflection film (hereinafter also referred to as a transparent substrate with an antireflection film) is known for preventing reflection of external light. For example, Patent Literature 1 discloses a transparent substrate with an antireflection film, which has light absorption ability and is insulating. Patent Document 2 discloses a transparent conductive laminate in which a silicon oxide layer and a copper layer are laminated in order. Patent Document 3 discloses an antireflection film in which a coating made of a high refractive index material and a coating made of a low refractive index material are provided on the surface of a glass plate, and the coating made of a low refractive index material is arranged on the outermost surface. there is

JP 2018-115105 A JP 2016-068470 A Japanese Patent Application Laid-Open No. 2008-201633

However, conventional transparent substrates with an antireflection film cannot sufficiently suppress the reflection of outside light, leaving room for further prevention of reflection of outside light.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a transparent substrate with an antireflection film in which reflection of external light is sufficiently suppressed, and an image display device having the same.

The present invention is as follows.
(1) A transparent substrate with an antireflection film having a transparent substrate having two main surfaces and a diffusion layer and an antireflection film on one of the main surfaces of the transparent substrate in this order, comprising: (A) the antireflection film; The outermost surface of the transparent substrate has a luminous reflectance (SCI Y) of 1% or less, and (B) the antireflection film has a laminated structure in which at least two dielectric layers having different refractive indices are laminated , (C) SCE, which is the ratio of the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with the antireflection film to the luminous reflectance (SCI Y) of the outermost surface of the transparent substrate with the antireflection film; Y/SCI Y is 0.15 or more,
Transparent substrate with antireflection film.
(2) The transparent substrate with an antireflection film according to (1), wherein the laminate of the transparent substrate and the diffusion layer has a haze value of 10% or more.
(3) The transparent substrate with an antireflection film according to (1) or (2) above, which has a luminous transmittance (Y) of 20 to 90%.
(4) The transparent substrate with an antireflection film according to any one of (1) to (3) above, wherein the antireflection film has a sheet resistance of 10 ⁴ Ω/□ or more.
(5) The transparent substrate with an antireflection film according to any one of (1) to (4) above, which has a b ^* value of 5 or less in transmission color under a D65 light source.
(6) At least one layer of the dielectric layers is mainly composed of an oxide of Si, and at least one other layer of the layers of the laminated structure is mainly composed of Mo and W from group A. Composed of a mixed oxide of at least one selected oxide and at least one oxide selected from the group B consisting of Si, Nb, Ti, Zr, Ta, Al, Sn and In, the mixed oxide (1) wherein the content of the group B element contained in the mixed oxide is 65% by mass or less with respect to the total of the group A element contained in the substance and the group B element contained in the mixed oxide; The transparent substrate with an antireflection film according to any one of (5).
(7) The transparent substrate with an antireflection film according to any one of (1) to (6) above, further comprising an antifouling film on the antireflection film.
(8) The transparent substrate with an antireflection film according to any one of (1) to (7) above, wherein the transparent substrate contains glass.
(9) The antireflection film-attached transparent according to any one of (1) to (8) above, wherein the transparent substrate contains at least one resin selected from polyethylene terephthalate, polycarbonate, acrylic, silicone, or triacetylcellulose. Substrate.
(10) Any one of (1) to (9) above, wherein the transparent substrate is a laminate of glass and at least one resin selected from polyethylene terephthalate, polycarbonate, acrylic, silicone, or triacetylcellulose. 3. The transparent substrate with an antireflection film according to .
(11) The transparent substrate with an antireflection film according to (8) or (10), wherein the glass is chemically strengthened.
(12) The transparent substrate with an antireflection film according to any one of (1) to (11) above, wherein the main surface of the transparent substrate on which the antireflection film is provided is subjected to an antiglare treatment.
(13) An image display device comprising the transparent substrate with an antireflection film according to any one of (1) to (12) above.

According to one aspect of the present invention, there is provided a transparent substrate with an antireflection film in which reflection of external light is sufficiently suppressed. The antireflection film-attached transparent substrate of one embodiment of the present invention is suitable as a cover glass for an image display device due to the above characteristics.
Further, according to one aspect of the present invention, there is provided an image display device comprising the transparent substrate with the antireflection film.

FIG. 1 is a cross-sectional view schematically showing one configuration example of a transparent substrate with an antireflection film according to one embodiment of the present invention. (a) to (d) of FIG. 2 are laser micrographs of the surface profile of the anti-glare PET film used in some of the examples. FIGS. 3(a) to 3(d) are laser micrographs of the surface profile of the anti-glare PET film or anti-glare TAC film used in some of the examples.

Hereinafter, embodiments of the present invention will be described in detail.
In this specification, having another layer or film on the main surface of a substrate such as a transparent substrate, on a layer such as a diffusion layer, or on a film such as an antireflection film means that the other layer or film etc. is not limited to the mode in which they are provided in contact with the main surface, layer, or film, but may be any mode in which a layer, film, or the like is provided in the upward direction. For example, having a diffusion layer on the main surface of the transparent substrate means that the diffusion layer may be provided so as to be in contact with the main surface of the transparent substrate, or any other layer or layer may be provided between the transparent substrate and the diffusion layer. A membrane or the like may be provided.

A transparent substrate with an antireflection film according to one aspect of the present invention includes a transparent substrate having two main surfaces and a transparent substrate with an antireflection film having a diffusion layer and an antireflection film on one of the main surfaces of the transparent substrate in this order. (A) the outermost surface of the transparent substrate with antireflection film has a luminous reflectance (SCI Y) of 1% or less; and (B) the antireflection films are dielectric layers having different refractive indices from each other. (C) the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with the antireflection film and the luminous reflectance of the outermost surface of the transparent substrate with the antireflection film SCE Y/SCI Y, which is a ratio to (SCI Y), is 0.15 or more.

FIG. 1 is a cross-sectional view schematically showing one configuration example of a transparent substrate with an antireflection film according to one embodiment of the present invention. A diffusion layer 31 is formed on a transparent substrate 10 , and an antireflection film (multilayer film) 30 is formed on the diffusion layer 31 .

<Transparent substrate>
In this embodiment, the transparent substrate having two main surfaces (hereinafter also simply referred to as transparent substrate) preferably has a refractive index of 1.4 or more and 1.7 or less. If the refractive index of the transparent substrate is within the above range, reflection on the bonding surface can be sufficiently suppressed when optically bonding a display, a touch panel, or the like. The refractive index is more preferably 1.45 or more, still more preferably 1.47 or more, and more preferably 1.65 or less, still more preferably 1.6 or less.

The transparent substrate preferably contains at least one of glass and resin. More preferably, the transparent substrate contains both glass and resin.
When the transparent substrate contains glass, it is possible to obtain a clear, high-quality image by arranging it on the display surface due to the high surface flatness of the glass.
When the transparent substrate contains a resin, it is less likely to break due to an external impact, and is safer than glass. Further, when a transparent film such as PET or TAC is selected as the resin, continuous processing with rolls is possible as a method of forming a diffusion layer for anti-glare treatment, and cost can be reduced. Furthermore, by applying fine particles of various materials as a diffusion layer, there is an advantage that the degree of freedom in designing the diffusion layer is increased compared to the technique of etching the glass surface.
In the case where the transparent substrate contains both glass and resin, the flatness of the glass can be improved by, for example, laminating a resin film having a diffusion layer formed thereon to the glass so that the transparent substrate contains both the glass and the resin. The advantages of both glass and resin can be provided, such as a scattering prevention function due to the nature and resin, and a diffusion layer with a high degree of freedom in design.

When the transparent substrate contains glass, the type of glass is not particularly limited, and glasses having various compositions can be used. Above all, the glass preferably contains sodium, and preferably has a composition capable of being strengthened by molding and chemical strengthening treatment. Specific examples include aluminosilicate glass, soda lime glass, borosilicate glass, lead glass, alkali barium glass, and aluminoborosilicate glass.
In this specification, when the transparent substrate contains glass, the transparent substrate is also referred to as a glass substrate.

The thickness of the glass substrate is not particularly limited, but when the glass is subjected to chemical strengthening treatment, it is usually preferably 5 mm or less, more preferably 3 mm or less, and further preferably 1.5 mm or less in order to perform chemical strengthening effectively. preferable. Moreover, it is usually 0.2 mm or more.

The glass substrate is preferably chemically strengthened glass. This increases the strength of the transparent substrate with antireflection film. When the glass substrate is subjected to antiglare treatment, which will be described later, chemical strengthening is performed after antiglare treatment and before forming an antireflection film (multilayer film).

It is preferable that the main surface of the glass substrate on the side having the antireflection film is subjected to antiglare treatment. Thereby, the anti-glare property of the transparent substrate can be enhanced, and the image observed through the transparent substrate becomes clear.

When the transparent substrate contains a resin, the type of resin is not particularly limited, and resins having various compositions can be used. Among them, the resin is preferably a thermoplastic resin or a thermosetting resin, and examples thereof include polyvinyl chloride resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl acetate resin, polyester resin, polyurethane resin, cellulose resin, acrylic resin. Resin, AS (acrylonitrile-styrene) resin, ABS (acrylonitrile-butadiene-styrene) resin, fluorine resin, thermoplastic elastomer, polyamide resin, polyimide resin, polyacetal resin, polycarbonate resin, modified polyphenylene ether resin, polyethylene terephthalate resin, poly Butylene terephthalate resins, polylactic acid resins, cyclic polyolefin resins, polyphenylene sulfide resins, and the like can be mentioned. Cellulose-based resins are preferred among these, and triacetyl cellulose resins, polycarbonate resins, polyethylene terephthalate resins and the like can be mentioned. These resins may be used individually by 1 type, and may use 2 or more types together.
It is particularly preferred that the resin contains at least one resin selected from polyethylene terephthalate, polycarbonate, acrylic, silicone and triacetylcellulose. These resins are colorless and transparent, have high transmittance and low scattering, are relatively inexpensive due to their high availability, and are preferable because they can impart functions as main components of hard coats and pressure-sensitive adhesives.
In this specification, when the transparent substrate contains a resin, the transparent substrate is also referred to as a resin substrate.

The shape of the resin substrate is preferably film-like. When the resin substrate is in the form of a film, that is, when it is a resin film, the thickness is not particularly limited, but is preferably 20 to 150 μm, more preferably 40 to 80 μm.

When the transparent substrate contains both glass and resin, for example, the resin substrate may be provided on the glass substrate.

A diffusion layer, which will be described later, is provided on one main surface of the transparent substrate. Examples include substrate-antiglare layer, glass substrate-antiglare layer, and the like.
Specific examples of the resin substrate-antiglare layer include an antiglare PET film and an antiglare TAC film. Anti-glare PET films include those manufactured by Higashiyama Film Co., Ltd., trade names: BHC-III and EHC-30a, and those manufactured by Reiko Co., Ltd. As the anti-glare TAC film, an anti-glare TAC film (manufactured by Toppan Tomoegawa Optical Film Co., trade name VZ50), an anti-glare TAC film (manufactured by Toppan Tomoegawa Optical Film Co., trade name VH66H), and the like are used.
As will be described later, the glass substrate-antiglare layer is obtained by applying an antiglare treatment to the main surface of the glass substrate on the antireflection film side to provide an antiglare layer.

The laminate preferably has a haze value of 10% or more, more preferably 15% or more, even more preferably 20% or more, even more preferably 25% or more, and 50% It is particularly preferable that it is above. When the haze value of the laminate is within the above range, reflection of external light can be more effectively suppressed. Also, the haze value is preferably 90% or less, more preferably 85% or less, and even more preferably 82% or less. When the haze value of the laminate is within the above range, it is possible to suppress deterioration of the resolution of the display, and it is possible to suppress whitening of the image when external light enters the display.
The haze value is measured according to JIS K 7136:2000 using a haze meter (Model HR-100, manufactured by Murakami Color Laboratory Co., Ltd.) or the like.

Sa (arithmetic mean surface roughness) of the laminate is preferably 0.05 to 0.6 μm, more preferably 0.05 to 0.55 μm. Sa is defined in ISO25178, and can be measured using, for example, a laser microscope VK-X3000 manufactured by Keyence Corporation. A small Sa means that the outermost surface unevenness of the transparent substrate is small, and the diffusivity of the reflected light is lowered, so that the diffuse reflectance (SCE Y) is lowered, making it difficult to obtain the effect of suppressing glare. A large Sa means that the surface unevenness is large, and although the diffuse reflectance is high, surface stains are difficult to remove, which is not preferable as a display surface material. Sa is used as a diffusion material by appropriately changing parameters such as the type of fine particles used as a diffusion material, the average particle size, and the amount of mixture, appropriately controlling the etching conditions for surface treatment, and by controlling the unbalanced diffusion layer such as sol-gel silica can be adjusted by appropriately curing and forming the

The laminate has a developed area ratio Sdr (hereinafter also simply referred to as “Sdr”) calculated from the surface area obtained by measurement using a laser microscope VK-X3000 manufactured by Keyence Corporation or the like, and is 0.001 to 0. 12 is preferred, and 0.0025 to 0.11 is more preferred.
Sdr is defined in ISO25178 and represented by the following formula.
Development area ratio Sdr={(AB)/B}
A: Surface area (development area) reflecting the actual unevenness in the measurement area
B: Area of flat surface without unevenness in the measurement area A small Sdr means that the surface area of the transparent substrate is small. becomes smaller, making it difficult to obtain the effect of suppressing reflection. A large Sdr means that the surface area of the transparent substrate is large, and the area of the antireflection layer that is exposed to the outside air is relatively increased. For Sdr, parameters such as the type of fine particles used as a diffusion material, the average particle size, and the amount of inclusion are appropriately changed, the etching conditions for surface treatment are appropriately controlled, and an unbalanced diffusion layer such as a sol-gel silica system is used. can be adjusted by appropriately curing and forming the

The laminate preferably has an Sdq (root mean square slope) of 0.03 to 0.50, more preferably 0.07 to 0.49. Sdq is defined in ISO25178 and can be measured with, for example, a laser microscope VK-X3000 manufactured by Keyence Corporation. A small Sdq means that the root-mean-square slope is small, the diffusivity of the reflected light is low, the diffuse reflectance (SCE Y) is small, and it is difficult to obtain the glare suppressing effect. When Sdq is large, the root-mean-square slope becomes large and the sharpness of the outermost surface of the transparent substrate increases. Sdq appropriately changes the parameters such as the type of fine particles used as a diffusion material, the average particle size, and the amount of mixture, appropriately controls the etching conditions for surface treatment, and controls the unbalanced diffusion layer such as sol-gel silica can be adjusted by appropriately curing and forming the

The laminate preferably has an Spc (average principal curvature of peak points on the surface) of 150 to 2500 (1/mm). Spc is defined in ISO25178, and can be measured using, for example, a laser microscope VK-X3000 manufactured by Keyence Corporation. If the Spc is small, the arithmetic mean curvature of the peak point becomes small, the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate becomes small, and the glare suppressing effect cannot be obtained. If the Spc is large, the arithmetic mean curvature of the peak point becomes large, and when touched with a finger or a cloth, the feeling of being caught becomes worse. Spc appropriately changes parameters such as the type of fine particles used as a diffusion material, the average particle size, and the amount of mixture, appropriately controls the etching conditions for surface treatment, and controls the unbalanced diffusion layer such as sol-gel silica. can be adjusted by appropriately curing and forming the

<Diffusion layer>
The diffusion layer in this aspect is provided on one main surface of the transparent substrate described above. Diffusion layer means a layer that has the function of diffusing specularly reflected light and reducing glare and glare, such as an anti-glare layer that has a function of diffusing specularly reflected light (anti-glare property) to a hard coat layer. is mentioned.

Since the anti-glare layer has an uneven surface on one side, it scatters light, increases the haze value, and imparts anti-glare properties. The anti-glare layer is composed of an anti-glare layer composition in which at least a particulate substance having anti-glare properties per se is dispersed in a solution in which a polymer resin is dissolved as a binder. The antiglare layer can be formed by applying the above antiglare layer composition, for example, to one main surface of a transparent substrate.

Examples of the antiglare particulate substance include inorganic fine particles such as silica, clay, talc, calcium carbonate, calcium sulfate, barium sulfate, aluminum silicate, titanium oxide, synthetic zeolite, alumina, and smectite, as well as styrene. Organic fine particles including resins, urethane resins, benzoguanamine resins, silicone resins, acrylic resins, and the like can be mentioned.

Polymer resins as binders for the hard coat layer or the antiglare layer include, for example, polyester resins, acrylic resins, acrylic urethane resins, polyester acrylate resins, polyurethane acrylate resins, epoxy acrylate resins, Polymer resins including urethane-based resins and the like can be used.

Further, when the transparent substrate is a glass substrate, the main surface of the glass substrate on which the antireflection film is provided is subjected to antiglare treatment to provide a diffusion layer on one main surface of the glass substrate. may Thereby, the anti-glare property of the transparent substrate can be enhanced, and the image observed through the transparent substrate becomes clear.
The method of antiglare treatment is not particularly limited, and for example, a method of applying a surface treatment to the main surface of the glass substrate to form desired unevenness can be used.
Specifically, a method of chemically treating the main surface of the glass substrate, for example, a method of frosting, can be used. In frost treatment, for example, a glass substrate to be treated is immersed in a mixed solution of hydrogen fluoride and ammonium fluoride, and the immersed surface can be chemically treated.
In addition to the method of chemical treatment such as frost treatment, for example, a so-called sandblasting treatment in which crystalline silicon dioxide powder, silicon carbide powder or the like is blown onto the surface of the glass substrate with pressurized air, or crystalline silicon dioxide powder. Alternatively, a physical treatment such as polishing with a water-moistened brush to which silicon carbide powder or the like is adhered can also be used.

<Anti-reflection film>
The antireflection film in this aspect has a laminated structure in which at least two dielectric layers having different refractive indices are laminated, and has a function of suppressing reflection of light.
The antireflection film (multilayer film) 30 shown in FIG. 1 has a laminated structure in which two layers of a first dielectric layer 32 and a second dielectric layer 34 having different refractive indices are laminated. Light reflection is suppressed by laminating the first dielectric layer 32 and the second dielectric layer 34 having different refractive indices. The first dielectric layer 32 is a high refractive index layer and the second dielectric layer 34 is a low refractive index layer.

In the antireflection film (multilayer film) 30 shown in FIG. 1, the first dielectric layer 32 is composed mainly of at least one oxide selected from Group A consisting of Mo and W, Si, Nb, Ti, Zr, It is preferably composed of a mixed oxide with at least one oxide selected from the B group consisting of Ta, Al, Sn and In. However, in the mixed oxide, the content ratio of the group B element contained in the mixed oxide to the total of the group A element contained in the mixed oxide and the group B element contained in the mixed oxide (hereinafter referred to as group B content) is preferably 65% by mass or less. Here, "mainly" means a component having the largest content (based on mass) in the first dielectric layer 32, and means that the corresponding component is contained in an amount of 70% by mass or more, for example.

Mixed oxidation of at least one oxide selected from Group A consisting of Mo and W and at least one oxide selected from Group B consisting of Si, Nb, Ti, Zr, Ta, Al, Sn and In When the group B content in the first dielectric layer (ABO) 32 is 65% by mass or less, it is possible to suppress yellowing of transmitted light.

The second dielectric layer 34 is preferably composed mainly of an oxide of Si (SiO _x ). Here, "mainly" means a component having the largest content (based on mass) in the second dielectric layer 34, and means that the corresponding component is contained in an amount of 70% by mass or more, for example.

The first dielectric layer 32 is selected from at least one oxide selected from the group A consisting of Mo and W and the group B consisting of Si, Nb, Ti, Zr, Ta, Al, Sn and In. It preferably consists of a mixed oxide with at least one oxide. Among these, Mo is preferred as Group A, and Nb is preferred as Group B.

By using Mo and Nb for the oxygen-deficient second dielectric layer 34 and the first dielectric layer 32, the conventional oxygen-deficient silicon oxide layer is yellowish in visible light. , Mo and Nb, the silicon oxide layer is not yellowed even if oxygen deficiency occurs.

The refractive index of the first dielectric layer 32 at a wavelength of 550 nm is preferably 1.8 to 2.3 from the viewpoint of transmittance with the transparent substrate 10 .

The extinction coefficient of the first dielectric layer 32 is preferably 0.005 to 3, more preferably 0.04 to 0.38. If the extinction coefficient is 0.005 or more, a desired absorptance can be achieved with an appropriate number of layers. Further, if the extinction coefficient is 3 or less, it is relatively easy to achieve both reflected color and transmittance.

The antireflection film (multilayer film) 30 shown in FIG. 1 has a two-layer structure in which a first dielectric layer 32 and a second dielectric layer are laminated. The (multilayer film) is not limited to this, and may have a laminated structure in which three or more dielectric layers having different refractive indices are laminated. In this case, the refractive indices of all dielectric layers need not be different. For example, in the case of a three-layered structure, a three-layered structure of a low refractive index layer, a high refractive index layer, and a low refractive index layer, or a three-layered structure of a high refractive index layer, a low refractive index layer, and a high refractive index layer. can. In the former case, the two low refractive index layers may have the same refractive index, and in the latter case, the two high refractive index layers may have the same refractive index. Further, for example, in the case of a four-layer laminate structure, a four-layer laminate structure of a low refractive index layer, a high refractive index layer, a low refractive index layer, and a high refractive index layer, or a high refractive index layer, a low refractive index layer, and a high refractive index layer. A four-layer laminate structure of a layer and a low refractive index layer can be obtained. In this case, the two low refractive index layers and the two high refractive index layers may have the same refractive index.

In the case of a laminated structure in which three or more layers having different refractive indices are laminated, dielectric layers other than the first dielectric layer (ABO) 32 and the second dielectric layer (SiO _x ) 34 are included. You can In this case, a three-layer laminated structure of a low refractive index layer, a high refractive index layer, and a low refractive index layer including the first dielectric layer (ABO) 32 and the second dielectric layer (SiO _x ) 34, Alternatively, a three-layer laminate structure of a high refractive index layer, a low refractive index layer, and a high refractive index layer, or a four-layer laminate structure of a low refractive index layer, a high refractive index layer, a low refractive index layer, and a high refractive index layer, or , a high refractive index layer, a low refractive index layer, a high refractive index layer, and a low refractive index layer.
However, the outermost layer is preferably the second dielectric layer (SiO _x ) 34 . In order to obtain low reflectivity, if the outermost layer is the second dielectric layer (SiO _x ) 34, it can be produced relatively easily. Further, when an antifouling film, which will be described later, is formed on the antireflection film 30, the antifouling film is formed on the second dielectric layer (SiO _x ) 34 from the viewpoint of bonding properties related to the durability of the antifouling film. is preferred.

The first dielectric layer (ABO) 32 is preferably amorphous. If it is amorphous, it can be produced at a relatively low temperature, and can be suitably applied when the transparent substrate 10 contains a resin, because the resin is not damaged by heat.

A halftone mask used in the semiconductor manufacturing field is known as an insulating light-transmitting film having a light absorbing ability. As the halftone mask, an oxygen deficient film such as a Mo-- _SiO.sub.2 film containing a small amount of Mo is used. A narrow bandgap film used in the field of semiconductor manufacturing is known as an insulating light-transmitting film having light absorption capability.
However, these light-transmitting films have a high ability to absorb light on the short wavelength side of visible light, so the transmitted light is yellowish. Therefore, it was unsuitable for the cover glass of an image display apparatus.

In a preferred embodiment of the present invention, the first dielectric layer 32 with an increased content of Mo or W and the second dielectric layer 34 made of _SiOx or the like are provided, thereby providing light absorption ability. , a transparent substrate with an antireflection film which is insulating and excellent in adhesion and strength can be obtained.

The antireflection film 30 in this embodiment can be formed on the main surface of the transparent substrate 10 using a known film forming method such as a sputtering method, a vacuum deposition method, or a coating method. That is, the dielectric layers constituting the antireflection film 30 are formed on the main surface of the diffusion layer 31 according to the order of lamination using a known film formation method such as sputtering, vacuum deposition, or coating. Also, the antireflection film 30 may be formed on the main surface of the transparent substrate by combining a plurality of film forming methods. For example, the antireflection film 30 is formed by a sputtering method, and only the outermost antifouling film is formed by a vapor deposition method or a coating method. There is a method of forming with an organic film having antifouling properties.

Among others, the antireflection film 30 is preferably formed by a method of laminating thin films in a vacuum, such as a sputtering method or a vacuum deposition method, from the viewpoints of low reflection, high durability, and high hardness. In addition, according to such a lamination method in a vacuum, the surface hardness is superior to that of forming an antireflection film by wet coating that cures and dries the coating liquid, the effect of reducing reflection is high, and the SCI Y value is stable. can be 1% or less, and the in-plane reflectance distribution is moderate.

Sputtering methods include magnetron sputtering, pulse sputtering, AC sputtering, digital sputtering, and the like.

For example, in the magnetron sputtering method, a magnet is placed on the back surface of a dielectric material, which is a base, to generate a magnetic field, and gas ions collide with the surface of the dielectric material and are ejected, thereby sputtering with a thickness of several nanometers. A method of depositing a film that can form a continuous film of dielectric material that is an oxide or nitride of the dielectric material.

In addition, for example, the digital sputtering method differs from the usual magnetron sputtering method in that a metal ultra-thin film is first formed by sputtering, and then oxidized by irradiation with oxygen plasma, oxygen ions, or oxygen radicals. This is a method of repeatedly forming metal oxide thin films in the same chamber. In this case, since the film forming molecules are metal when deposited on the substrate, it is presumed to be more ductile than the case of depositing a metal oxide. Therefore, even if the energy is the same, rearrangement of the film-forming molecules is likely to occur, and as a result, it is considered that a dense and smooth film can be formed.

<Anti-fouling film>
From the viewpoint of protecting the outermost surface of the antireflection film, the transparent substrate with an antireflection film of this embodiment further has an antifouling film (also referred to as an "Anti Finger Print (AFP) film") on the antireflection film. may The antifouling film can be composed of, for example, a fluorine-containing organosilicon compound. The fluorine-containing organosilicon compound can be used without particular limitation as long as it can impart antifouling properties, water repellency, and oil repellency. Fluorine-containing organosilicon compounds having one or more groups represented by The polyfluoropolyether group is a divalent group having a structure in which a polyfluoroalkylene group and an etheric oxygen atom are alternately bonded.

In addition, KP-801 (trade name, Shin-Etsu Chemical company), KY178 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), KY-130 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), KY-185 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) Optool (registered trademark) DSX and Optool AES ( All of them are trade names, manufactured by Daikin) and the like can be preferably used.

When the antireflection film-attached transparent substrate of this embodiment has an antifouling film, the antifouling film is provided on the antireflection film. When the antireflection film is provided on both of the two main surfaces of the transparent substrate, the antifouling film can be formed on both the antireflection films. A structure in which films are laminated may be used. This is because the antifouling film should be provided at a place where there is a possibility that a person's hand or the like may come into contact with it, and the antifouling film can be selected according to the application.

(Luminous reflectance: SCI Y)
The transparent substrate with an antireflection film of this embodiment has a luminous reflectance (SCI Y) of the outermost surface of 1% or less. When the luminous reflectance (SCI Y) is within the above range, when used as a cover glass for an image display device, the effect of preventing reflection of external light on the screen is high. The luminous reflectance (SCI Y) is preferably 0.9% or less, more preferably 0.8% or less, and even more preferably 0.75% or less.
The luminous reflectance (SCI Y) can be measured by the method specified in JIS Z 8722 (2009), as described in Examples below. Specifically, the luminous reflectance (SCI Y) of the two main surfaces of the transparent substrate, which is not the main surface on the antireflection film side, is the other main surface (hereinafter referred to as the back surface of the transparent substrate, or Measurement can be performed in a state in which reflection from the back surface is removed by attaching a black tape to the back surface. Although the calculation of SCI Y requires specification of the light source, it is preferable to use the D65 light source for the calculation because the present invention assumes suppression of glare in a bright place during the daytime.

In order to make the luminous reflectance (SCI Y) of 1% or less in the transparent substrate with an antireflection film of this embodiment, for example, the luminous transmittance (Y) of the transparent substrate with an antireflection film is set to 90% or less. do. To that end, the first dielectric layer consists mainly of at least one oxide selected from the group A consisting of Mo and W and the group B consisting of Si, Nb, Ti, Zr, Ta, Al, Sn and In. Preferably, a mixed oxide with at least one oxide selected from is used to control the amount of oxidation of the film. By adjusting the amount of oxidation and imparting absorption to the antireflection film, diffuse reflection from a diffusion layer or the like formed on the transparent substrate can be suppressed.

(Diffuse reflectance: SCE Y)
The diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with an antireflection film of this embodiment is preferably 0.05% or more, more preferably 0.1% or more, and even more preferably 0.2% or more. When the diffuse reflectance (SCE Y) is within the above range, when used as a cover glass of an image display device, the effect of preventing reflection of external light on the screen is enhanced, which is preferable.

The diffuse reflectance (SCE Y) is measured using a spectrophotometer (manufactured by Konica Minolta, trade name: CM-26d) according to the method specified in JIS Z 8722 (2009), as described in Examples below. measured using
Specifically, the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with the antireflection film is the one of the two main surfaces of the transparent substrate, which is not the main surface on the side of the antireflection film. (Hereinafter, also referred to as the back surface of the transparent substrate, or simply the back surface) is attached with a black tape, and the measurement is performed in a state where the back surface reflection is removed. The black tape should be one that does not substantially contain diffuse reflection components. The presence or absence of the diffuse reflection component can be determined by attaching a black tape to be evaluated for the diffuse reflection component to a transparent object such as float glass that has almost zero diffuse reflection component, and measuring SCE Y, which is the diffuse reflection component, from the glass surface. can be evaluated with Here, a black tape that does not substantially contain a diffuse reflection component means that SCE Y is 0.02% or less by the above-described measurement method. Although the calculation of SCE Y requires specification of the light source, it is preferable to use the D65 light source for the calculation because the present invention assumes suppression of glare in a bright place during the daytime.

That is, in the transparent substrate with an antireflection film of this embodiment, the diffuse reflectance (SCE Y) of the outermost surface is the diffuse reflectance of the other main surface of the two main surfaces of the transparent substrate, which is not the main surface on the side of the antireflection film. A black tape that does not substantially contain a diffuse reflection component is attached to the surface, and measurement is performed using a spectrophotometer according to the method specified in JIS Z 8722 (2009).

In evaluating the reflectance of the outermost surface of a transparent substrate with an antireflection film, a black material for removing back surface reflection is a very important factor. The black material must be in close contact with the main surface to eliminate the interface between the air and the main surface, and black tape or black paint is generally used. Also, in order to accurately evaluate the diffuse reflectance of the outermost surface, it is necessary to use a black material that has almost no diffuse reflection component. For example, when using a black tape, black vinyl tape (product name: 117, etc.) from 3M Company has a diffuse reflection component equivalent to about 0.7% in SCE Y with a D65 light source, so it is not suitable for this evaluation. is not suitable. On the other hand, Tomoegawa Paper Co., Ltd.'s black tape (trade name: Kukkiri Mieru) does not substantially contain a diffuse reflection component (diffuse reflectance is equivalent to approximately 0.01% in SCE Y with a D65 light source). It is preferably used for measurement in a state where such back surface reflection is removed.

As for the black paint, it is common to print a black light-shielding film on the back of the display front cover for the purpose of hiding the wiring around the screen from the viewer. and black paint manufactured by Jujo Chemical Co., Ltd. Such a black light-shielding film for displays is often made of a polyester-based ink mixed with a black pigment from the viewpoint of light resistance. This is unsuitable for the evaluation in which the ratio of the diffuse reflectance of the outermost surface of the antireflection film-coated transparent substrate is important.

In order to make the diffuse reflectance (SCE Y) of 0.05% or more in the transparent substrate with an antireflection film of this embodiment, for example, a diffusion layer such as an antiglare layer, or a laminate of a transparent substrate and a diffusion layer The haze value is preferably 10% or higher, more preferably 25% or higher, even more preferably 50% or higher.

(Diffuse reflectance: SCE Y/luminous reflectance: SCI Y)
In the transparent substrate with an antireflection film of this embodiment, the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with the antireflection film and the luminous reflectance (SCI Y) of the outermost surface of the transparent substrate with the antireflection film are It is important that SCE Y/SCI Y, which is the ratio of , is 0.15 or more.

The above luminous reflectance (SCI Y) is calculated by measuring total reflected light including regular reflected light and diffuse reflected light. color evaluation. On the other hand, the diffuse reflectance (SCE Y) is calculated by measuring only the diffusely reflected light with the specularly reflected light removed from the total reflected light, and thus is a color evaluation close to visual observation.
Therefore, when the diffuse reflectance (SCE Y) relative to the luminous reflectance (SCI Y) is high, it means that the ratio of diffusely reflected light to total reflected light (specularly reflected light + diffusely reflected light) is large. This is preferable because it reduces the reflection of outside light on the screen.

SCE Y/SCI Y is preferably 0.2 or more, more preferably 0.25 or more, still more preferably 0.3 or more, still more preferably 0.35 or more, still more preferably 0.4 or more, and 0.4 or more. 45 or higher is even more preferred, 0.5 or higher is even more preferred, and 0.6 or higher is particularly preferred. Also, SCE Y/SCI Y may be, for example, 1 or less, or may be 0.75 or less.

In order to make the SCE Y/SCI Y of 0.15 or more in the transparent substrate with an antireflection film of the present embodiment, it is preferable to use a laminate of a transparent substrate having a haze value of 10% or more and a diffusion layer, It is more preferable to use a laminate of a transparent substrate and a diffusion layer with a haze value of 25% or more, and more preferably a laminate of a transparent substrate and a diffusion layer with a haze value of 50% or more.

(Luminous transmittance: Y)
The transparent substrate with an antireflection film of this embodiment preferably has a luminous transmittance (Y) of 20 to 90%. If the luminous transmittance (Y) is within the above range, it has an appropriate light absorption ability, so that when used as a cover glass for an image display device, reflection of light can be suppressed. This improves the bright contrast of the image display device. The luminous transmittance (Y) is more preferably 50 to 90%, more preferably 60 to 90%.
In addition, the luminous transmittance (Y) may be 88% or less, 80% or less, 75% or less, 70% or less, or 30% It may be 40% or more.
The luminous transmittance (Y) can be measured by the method specified in JIS Z 8701 (1999) as described in Examples below.

In order to make the luminous transmittance (Y) of 20 to 90% in the transparent substrate with an antireflection film of this embodiment, for example, at least one selected from the group A consisting mainly of Mo and W is used as the first dielectric. and at least one oxide selected from the group B consisting of Si, Nb, Ti, Zr, Ta, Al, Sn and In to adjust the oxidation amount of the film. preferable.

The luminous transmittance (Y) of the transparent substrate with an antireflection film of this embodiment is, for example, the irradiation time of the oxidizing source when forming the first dielectric layer, which is a high refractive index layer, in the antireflection film described above. It can be adjusted by controlling the output, the distance from the substrate, and the amount of oxidizing gas.

(sheet resistance)
The sheet resistance of the antireflection film in the antireflection film-attached transparent substrate of this embodiment is preferably 10 ⁴ Ω/□ or more. When the sheet resistance of the antireflection film is in the above range, the antireflection film is insulating, so when it is used as a cover glass of an image display device, even if a touch panel is attached, the finger required for a capacitive touch sensor is not affected. The change in capacitance due to the contact is maintained, and the touch panel can be made to function. The sheet resistance is more preferably 10 ⁶ Ω/square or more, more preferably 10 ⁸ Ω/square or more.
The sheet resistance can be measured by the method specified in JIS K 6911 (2006), as described in Examples below.

In the transparent substrate with an antireflection film of this embodiment, the metal content in the antireflection film is adjusted, for example, in order to make the sheet resistance of the antireflection film 10 ⁴ Ω/□ or more.

(b ^* value in transmission color under D65 light source)
The transparent substrate with an antireflection film of this aspect preferably has a b ^* value of 5 or less in transmission color under a D65 light source. When the b ^* value is in the above range, the transmitted light is not yellowish, so it is suitable for use as a cover glass for an image display device. The b ^* value is more preferably 3 or less, more preferably 2 or less. The lower limit of the b ^* value is preferably −6 or more, more preferably −4 or more. It is preferable that the b ^* value is in the above range because the transmitted light is colorless and does not interfere with the transmitted light.
The b ^* value in transmission color under D65 light source can be measured by the method specified in JIS Z 8729 (2004) as described in Examples below.

In order to make the b ^* value of 5 or less in the transmission color under the D65 light source in the transparent substrate with an antireflection film of this embodiment, for example, the material composition of the first dielectric is adjusted. Specifically, by increasing the ratio of the above group A, the short wavelength transmittance is increased, and a decrease in the b ^* value can be expected.

(Brightness of diffuse reflected light: SCE L ^* )
The transparent substrate with an antireflection film of this embodiment preferably has a lightness (SCE L ^* ) of diffusely reflected light of 7 or less. When the lightness (SCE L ^* ) of the diffusely reflected light is in the above range, the effect of preventing reflection of external light on the screen becomes higher when used as a cover glass of an image display device, which is preferable. The lightness (SCE L ^* ) of the diffusely reflected light is more preferably 6 or less, and even more preferably 5 or less.
The lightness (SCE L ^* ) of the diffusely reflected light was measured by a spectrophotometer (manufactured by Konica Minolta Co., Ltd., trade name: CM -26d). Specifically, the lightness of the diffusely reflected light (SCE L ^* ) is measured on the other main surface (hereinafter referred to as the back surface of the transparent substrate, (or simply referred to as the back surface) can be attached with a black tape to remove the reflection from the back surface.

In the transparent substrate with an antireflection film of this aspect, in order to make the lightness (SCE L ^* ) of diffusely reflected light 7 or less, for example, the haze of a diffusion layer such as an antiglare layer, or a laminate of a transparent substrate and a diffusion layer obtained by reducing the value.

(Brightness of total reflected light: SCI L ^* )
The lightness (SCI L ^* ) of total reflected light of the transparent substrate with an antireflection film of this embodiment is preferably 9 or less. When the lightness of the totally reflected light (SCI L ^* ) is within the above range, the effect of preventing the reflection of external light on the screen becomes higher when used as a cover glass of an image display device, which is preferable. The lightness (SCI L ^* ) of the totally reflected light is more preferably 8 or less, even more preferably 6 or less.
The lightness of the total reflected light (SCI L ^* ) was measured by a spectrophotometer (manufactured by Konica Minolta, trade name: CM -26d). Specifically, the lightness (SCI L ^* ) of the total reflected light is measured on the other main surface (hereinafter referred to as the back surface of the transparent substrate, (or simply referred to as the back surface) can be attached with a black tape to remove the reflection from the back surface.

In the transparent substrate with an antireflection film of this aspect, in order to make the lightness (SCI L ^* ) of total reflected light 9 or less, for example, the haze of a diffusion layer such as an antiglare layer, or a laminate of a transparent substrate and a diffusion layer value, or the luminous transmittance (Y) of the transparent substrate with an antireflection film is made 90% or less.

(Application)
The transparent substrate with an antireflection film of this embodiment is suitable as a cover glass for an image display device, particularly an image display device mounted on a vehicle such as an image display device for a navigation system mounted on a vehicle. be. The antireflection film-coated transparent substrate of this embodiment makes it difficult for internal structures and people illuminated by external light such as the sun to be reflected on the screen, and in particular when the transparent substrate contains both glass and resin, the quality of the display is improved. and anti-scattering performance can be expected. A liquid crystal display (LCD) having high heat resistance and durability is adopted as an image display device of a navigation system mounted on a vehicle or the like. In addition, it is suitable as a surface material for a large-screen image display device because of the property that the surrounding objects are less likely to be reflected on the display. As such image display devices, in addition to liquid crystal displays, LED displays with high brightness and organic EL displays with high bright contrast are employed.

(Image display device)
An image display device of one aspect of the present invention includes the transparent base with the antireflection film. Examples of the image display device include a liquid crystal display (LCD), an LED display, an organic EL display, or the like, and a mode in which the above-mentioned transparent substrate with an antireflection film is provided on the display.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these. Examples 1 to 10 are working examples, and examples 11 to 15 are comparative examples.

(Example 1)
A diffusion layer and an antireflection film were formed in this order on one main surface of a transparent substrate by the following method to prepare a transparent substrate with an antireflection film. As for the transparent substrate, as will be described later, a mode in which a resin substrate is provided on a glass substrate was adopted.

An anti-glare PET film ( Reiko Co., Ltd., Sa: 0.274 μm, Sdr: 0.1083, Sdq: 0.48, Spc: 1931 (1 / mm), haze value: 79%) by laminating with acrylic transparent adhesive A diffusion layer was provided on a transparent substrate. FIG. 2(a) shows a photograph of the surface shape of the anti-glare PET film with a laser microscope VK-X3000 manufactured by Keyence Corporation.

Next, using a target obtained by sintering a mixture of niobium and molybdenum at a weight ratio of 50:50 by the digital sputtering method as the dielectric layer (1) (high refractive index layer), pressure was applied with argon gas. is maintained at 0.2 Pa, pulse sputtering is performed under the conditions of a frequency of 100 kHz, a power density of 10.0 W/cm ² , and an inverted pulse width of 3 μsec to form a metal film with a small thickness, which is immediately oxidized with oxygen gas. By repeating this process at high speed, an oxide film was formed, and a Mo--Nb--O layer of 20 nm was formed on the main surface of the transparent substrate to which the diffusion layer was bonded.

Then, using a silicon target by the same digital sputtering method as the dielectric layer (2) (low refractive index layer), while maintaining the pressure at 0.2 Pa with argon gas, the frequency was 100 kHz and the power density was 10.0 W / cm. ^2. Pulse sputtering is performed under the condition of an inverted pulse width of 3 μsec to form a silicon film having a small thickness, and immediately thereafter, oxidation with oxygen gas is repeated at high speed to form a silicon oxide film. A layer of silicon oxide [silica (SiO _x )] having a thickness of 30 nm was formed on the -Nb-O layer. Here, the flow rate of oxygen for oxidation with oxygen gas was 500 sccm, and the input power of the oxidation source was 1000W.

Next, using a target obtained by sintering a mixture of niobium and molybdenum at a weight ratio of 50:50 by the same digital sputtering method as the dielectric layer (3) (high refractive index layer), argon gas was used. While maintaining the pressure at 0.2 Pa, pulse sputtering is performed under the conditions of a frequency of 100 kHz, a power density of 10.0 W/cm ² , and an inverted pulse width of 3 μsec to form a metal film with a small thickness. An oxide film was formed by repeating oxidation at high speed, and a Mo--Nb--O layer having a thickness of 120 nm was formed on the silicon oxide layer.

Subsequently, using a silicon target by the same digital sputtering method as the dielectric layer (4) (low refractive index layer), while maintaining the pressure at 0.2 Pa with argon gas, the frequency was 100 kHz and the power density was 10.0 W/. cm ² and an inverted pulse width of 3 μsec to form a silicon film with a small film thickness, and immediately after that, oxidizing with oxygen gas is repeated at high speed to form a silicon oxide film. A layer of silicon oxide [silica (SiO _x )] having a thickness of 88 nm was deposited on the -Nb-O layer. Here, the flow rate of oxygen for oxidation with oxygen gas was 500 sccm, and the input power of the oxidation source was 1000W.
As described above, an antireflection film was provided on the diffusion layer, and KY-185 manufactured by Shin-Etsu Chemical Co., Ltd. was vacuum-deposited to a thickness of 4 nm as an antifouling film on the uppermost layer to obtain a transparent substrate with an antireflection film.

The following evaluations were carried out on the produced transparent substrate with an antireflection film.

(Luminous transmittance: Y)
The luminous transmittance (Y) of the produced transparent substrate with an antireflection film was measured by the method specified in JIS Z 8701 (1999). The spectral transmittance was measured with a spectrophotometer (manufactured by Shimadzu Corporation, trade name: SolidSpec-3700), and the luminous transmittance (stimulus value Y defined in JIS Z 8701 (1999)) was obtained by calculation. . A D65 light source was used to calculate the stimulus value Y.

(Luminous reflectance: SCI Y)
In the produced transparent substrate with antireflection film, the luminous reflectance (SCI Y) of the outermost surface of the transparent substrate with antireflection film was measured by the method specified in JIS Z 8722 (2009). Specifically, of the two main surfaces of the transparent substrate, by attaching a black tape to the other main surface that is not the main surface on the antireflection film side, the spectrophotometer (manufactured by Konica Minolta, trade name: CM-26d) was used to measure the total reflected light luminous reflectance (SCI Y). A D65 light source was used as the light source. For the black tape, "Kikkiri Mieru" manufactured by Tomoegawa Paper Co., Ltd. was used.

(Brightness of total reflected light: SCI L ^* )
The lightness (SCI L ^* ) of total reflected light in the produced transparent substrate with an antireflection film was measured by the method specified in JIS Z 8722 (2009). Specifically, of the two main surfaces of the transparent substrate, by attaching a black tape to the other main surface that is not the main surface on the antireflection film side, the spectrophotometer (manufactured by Konica Minolta, trade name: CM-26d) was used to measure the lightness of total reflected light (SCI L ^* ). A D65 light source was used as the light source. For the black tape, "Kikkiri Mieru" manufactured by Tomoegawa Paper Co., Ltd. was used.

(Diffuse reflectance: SCE Y)
In the produced transparent substrate with an antireflection film, the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with an antireflection film was measured by the method specified in JIS Z 8722 (2009). Specifically, of the two main surfaces of the transparent substrate, by attaching a black tape to the other main surface that is not the main surface on the antireflection film side, the spectrophotometer (manufactured by Konica Minolta, trade name: CM-26d) was used to measure the diffuse reflectance (SCE Y). A D65 light source was used as the light source. For the black tape, "Kikkiri Mieru" manufactured by Tomoegawa Paper Co., Ltd. was used. In addition, the diffuse reflectance of the clear mirror is about 0.01% in SCEY value with D65 light source, and does not substantially contain a diffuse reflection component.

(Brightness of diffuse reflected light: SCE L ^* )
The lightness of diffusely reflected light (SCE L ^* ) of the produced transparent substrate with an antireflection film was measured by the method specified in JIS Z 8722 (2009). Specifically, of the two main surfaces of the transparent substrate, by attaching a black tape to the other main surface that is not the main surface on the antireflection film side, the spectrophotometer (manufactured by Konica Minolta, trade name: CM-26d) was used to measure the lightness of diffusely reflected light (SCE L ^* ). A D65 light source was used as the light source. For the black tape, "Kikkiri Mieru" manufactured by Tomoegawa Paper Co., Ltd. was used.

(Transmission color (b ^* value) of transparent substrate with antireflection film under D65 light source)
A color index (b ^* value) specified in JIS Z 8729 (2004) was obtained from the transmission spectrum obtained by measuring the above spectral transmittance. A D65 light source was used as the light source.

(Sheet resistance of antireflection film)
A sheet resistance value was measured according to JIS K 6911 (2006) using a measuring device (manufactured by Mitsubishi Chemical Analytic Tech, device name: Hiresta UP (MCP-HT450 type)). A probe was applied to the center of the transparent substrate with an antireflection film, and a voltage of 10 V was applied for 10 seconds to measure.

(Scratch resistance test)
A rub test was performed for scratch resistance evaluation. A rubbing test was performed on a transparent substrate with an anti-reflection film by using a cloth No. 3 of Kanawa impregnated with ethanol and applying a load of 1 kg/cm ² for 1,000 reciprocations. After that, it was visually observed whether the surface of the antireflection film-coated transparent substrate was scratched or not. As a control example, the same test was performed on a sample having an anti-glare layer on the outermost surface without providing an antireflection film.

(Example 2)
A film was formed in the same manner as in Example 1 except that the laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Reiko Co., Ltd.) having the physical properties shown in Table 1. got The evaluation results are shown in Table 2 below.

(Example 3)
A film was formed in the same manner as in Example 1, except that the laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., product name: BHC-III) having the physical properties shown in Table 1. No. 3 transparent substrate with an antireflection film was obtained. The evaluation results are shown in Table 2 below.

(Example 4)
The laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., trade name: EHC-30a) having the physical properties shown in Table 1, and the first dielectric layer was oxidized with oxygen gas. Film formation was carried out in the same manner as in Example 1, except that the flow rate of oxygen was changed from 500 sccm to 800 sccm, and a transparent substrate with an antireflection film of Example 4 was obtained. The evaluation results are shown in Table 2 below.

(Example 5)
A film was formed in the same manner as in Example 1, except that the laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., product name: EHC-30a) having the physical properties shown in Table 1. No. 5 transparent substrate with an antireflection film was obtained. The evaluation results are shown in Table 2 below.

(Example 6)
The laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., product name: EHC-30a) having the physical properties shown in Table 1, and an oxidation source was added to the first dielectric layer. A film was formed in the same manner as in Example 1 except that the electric power was changed to 700 W, and a transparent substrate with an antireflection film of Example 6 was obtained. The evaluation results are shown in Table 2 below.

(Example 7)
When the laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Reiko Co., Ltd.) having the physical properties shown in Table 1, and the first dielectric layer was oxidized with oxygen gas, the oxygen flow rate was 800 sccm. A film was formed in the same manner as in Example 1 except that the composition was changed to , and a transparent substrate with an antireflection film of Example 7 was obtained. The evaluation results are shown in Table 2 below.

(Example 8)
A film was formed in the same manner as in Example 1 except that the laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Reiko Co., Ltd.) having the physical properties shown in Table 1, and the transparent substrate with an anti-reflection film of Example 8 got The evaluation results are shown in Table 2 below.

(Example 9)
Except that the laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Reiko Co., Ltd.) having the physical properties shown in Table 1, and the input power of the oxidation source of the first dielectric layer was changed to 700 W. was formed in the same manner as in Example 1 to obtain a transparent substrate with an antireflection film of Example 9. The evaluation results are shown in Table 2 below.

(Example 10)
A film was formed in the same manner as in Example 1 except that the laminate (resin film + anti-glare layer) was changed to an anti-glare TAC film (manufactured by Toppan Tomoegawa Optical Film Co., Ltd., trade name VZ50) having the physical properties shown in Table 1, and the reflection of Example 10 A transparent substrate with a protective film was obtained. The evaluation results are shown in Table 2 below.

(Example 11)
A film was formed in the same manner as in Example 1 except that the laminate (resin film + anti-glare layer) was changed to an anti-glare TAC film (manufactured by Toppan Tomoegawa Optical Film Co., Ltd., trade name CHC) having the physical properties shown in Table 1, and the reflection of Example 11 A transparent substrate with a protective film was obtained. The evaluation results are shown in Table 2 below.

(Example 12)
The laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., product name: EHC-10a) having the physical properties shown in Table 1, and an oxidation source was added to the first dielectric layer. A film was formed in the same manner as in Example 1 except that the electric power was changed to 700 W, and a transparent substrate with an antireflection film of Example 12 was obtained. The evaluation results are shown in Table 2 below.

(Example 13)
The laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., product name: EHC-05a) having the physical properties shown in Table 1, and an oxidation source was added to the first dielectric layer. A film was formed in the same manner as in Example 1 except that the power was changed to 700 W, and a transparent substrate with an antireflection film of Example 13 was obtained. The evaluation results are shown in Table 2 below.

(Example 14)
The laminate (resin film + anti-glare layer) was changed to an anti-glare PET film (manufactured by Higashiyama Film Co., Ltd., trade name: EHC-30a) having the physical properties shown in Table 1, and an anti-reflection film was formed by the method described below. A film was formed in the same manner as in Example 1 except that the transparent AR was changed to a transparent AR, and a transparent substrate with an antireflection film of Example 14 was obtained.

(Method for forming transparent AR film)
First, using a titanium target as the dielectric layer (1) (high refractive index layer) by digital sputtering, while maintaining the pressure at 0.2 Pa with argon gas, the frequency was 100 kHz, the power density was 10.0 W/cm ² , and the inversion was performed. Pulse sputtering was performed under the condition of a pulse width of 3 μsec to form a metal film with a small film thickness, and immediately thereafter, oxidation with oxygen gas was repeated at high speed to form an oxide film, and a diffusion layer was bonded. A Ti—O layer of 11 nm was formed on the main surface of the transparent substrate.

Then, using a silicon target by the same digital sputtering method as the dielectric layer (2) (low refractive index layer), while maintaining the pressure at 0.2 Pa with argon gas, the frequency was 100 kHz and the power density was 10.0 W / cm. ^2. Pulse sputtering is performed under the condition of an inverted pulse width of 3 μsec to form a silicon film with a small thickness, and immediately thereafter, oxidation with oxygen gas is repeated at high speed to form a silicon oxide film, Ti- A layer of silicon oxide [silica (SiO _x )] having a thickness of 35 nm was deposited on the O layer. Here, the flow rate of oxygen for oxidation with oxygen gas was 500 sccm, and the input power of the oxidation source was 1000W.

Next, using a titanium target in the same digital sputtering method as the dielectric layer (3) (high refractive index layer), while maintaining the pressure at 0.2 Pa with argon gas, the frequency was 100 kHz and the power density was 10.0 W/. cm ² and an inverted pulse width of 3 μsec to form a metal film with a small film thickness, and immediately after that, oxidizing with oxygen gas is repeated at high speed to form an oxide film and silicon oxide. A Ti—O layer with a thickness of 104 nm was deposited on top of the layer.

Subsequently, using a silicon target by the same digital sputtering method as the dielectric layer (4) (low refractive index layer), while maintaining the pressure at 0.2 Pa with argon gas, the frequency was 100 kHz and the power density was 10.0 W/. cm ² and an inverted pulse width of 3 μsec to form a silicon film with a small film thickness, and immediately after that, oxidizing with oxygen gas is repeated at high speed to form a silicon oxide film. A layer of silicon oxide [silica (SiO _x )] having a thickness of 86 nm was deposited on the —O layer. Here, the flow rate of oxygen for oxidation with oxygen gas was 500 sccm, and the input power of the oxidation source was 1000W.
The evaluation results are shown in Table 2 below.

(Example 15)
Example 1 was repeated except that the laminate (resin film + antiglare layer) was changed to one having the physical properties shown in Table 1 (manufactured by Reiko Co., Ltd.) and the antireflection film was changed to the same transparent AR as in Example 14. A transparent substrate with an antireflection film of Example 15 was obtained. The evaluation results are shown in Table 2 below.

As shown in Table 2, the transparent substrates with an antireflection film of Examples 1 to 10 have a luminous reflectance (SCI Y) of 1% or less and an SCE Y/SCI Y of 0.15 or more. When used as a cover glass for an image display device, the effect of preventing the reflection of external light is high, and when visually confirming the image of the reflected structure, etc., the outline of the image is blurred and the reflection is not noticeable. rice field.
On the other hand, the transparent substrates with an antireflection film of Examples 11 and 13 have SCE Y/SCI Y of less than 0.15, and the transparent substrates with an antireflection film of Examples 14 and 15 have a luminous reflectance (SCI Y ) is more than 1%, and when used as a cover glass for an image display device, the effect of preventing the reflection of external light is low, and when the image of the reflected structure, etc. is visually confirmed, the outline of the image is clear. It was a result that I was worried about the reflection.
In addition, in Examples 1 to 15, antireflection films were formed by sputtering and vacuum deposition. Scratches were visually observed in the control example in which the anti-glare layer was the outermost surface without providing the anti-glare layer. It was confirmed that the anti-reflection film formed in a vacuum improves the surface abrasion resistance.

10 transparent substrate 30 antireflection film 31 diffusion layer 32 first dielectric layer 34 second dielectric layer

Claims (13)

A transparent substrate having two main surfaces and a transparent substrate with an antireflection film having a diffusion layer and an antireflection film on one of the main surfaces of the transparent substrate in this order, comprising: (A) the transparent substrate with an antireflection film; (B) the antireflection film has a laminated structure in which at least two dielectric layers having different refractive indices are laminated, (C ) SCE Y/SCI, which is the ratio of the diffuse reflectance (SCE Y) of the outermost surface of the transparent substrate with the antireflection film to the luminous reflectance (SCI Y) of the outermost surface of the transparent substrate with the antireflection film Y is 0.15 or more,
Transparent substrate with antireflection film. 2. The transparent substrate with an antireflection film according to claim 1, wherein a laminate of said transparent substrate and said diffusion layer has a haze value of 10% or more. 2. The transparent substrate with an antireflection film according to claim 1, which has a luminous transmittance (Y) of 20 to 90%. 2. The transparent substrate with an antireflection film according to claim 1, wherein the antireflection film has a sheet resistance of 10 ^<4> [Omega]/square or more. 2. The transparent substrate with an antireflection film according to claim 1, which has a b ^* value of 5 or less in transmission color under a D65 light source. At least one layer of the dielectric layers is mainly composed of an oxide of Si, and another at least one layer of the layers of the laminated structure is selected from group A consisting mainly of Mo and W. composed of a mixed oxide of at least one oxide and at least one oxide selected from Group B consisting of Si, Nb, Ti, Zr, Ta, Al, Sn and In, and contained in the mixed oxide 2. The reflector according to claim 1, wherein the content of the group B element contained in the mixed oxide is 65% by mass or less with respect to the total of the group A element contained in the mixed oxide and the group B element contained in the mixed oxide. Transparent substrate with protective film. 2. The transparent substrate with an antireflection film according to claim 1, further comprising an antifouling film on said antireflection film. 2. The transparent substrate with an antireflection film according to claim 1, wherein said transparent substrate comprises glass. 2. The transparent substrate with an antireflection film according to claim 1, wherein said transparent substrate contains at least one resin selected from polyethylene terephthalate, polycarbonate, acryl, silicone and triacetyl cellulose. 2. The transparent substrate with an antireflection film according to claim 1, wherein said transparent substrate is a laminate of glass and at least one resin selected from polyethylene terephthalate, polycarbonate, acryl, silicone or triacetyl cellulose. 9. The transparent substrate with an antireflection film according to claim 8, wherein said glass is chemically strengthened. 2. The transparent substrate with an antireflection film according to claim 1, wherein the main surface of the transparent substrate on which the antireflection film is provided is subjected to an antiglare treatment. An image display device comprising the transparent substrate with an antireflection film according to any one of claims 1 to 12.

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