Substrate with anti-glare film and method for manufacturing substrate with anti-glare film

Abstract

The present invention relates to a substrate with an anti-glare film, which is a substrate (1) having a substrate (3) and an anti-glare film (5) formed on at least one main surface of the substrate (3), comprising: an anti-glare portion (50) on which the anti-glare film is formed on at least one main surface of the substrate; and a non-anti-glare portion (30) on which the anti-glare film is not formed on at least one main surface of the substrate, wherein the average value P obtained by using a specific (Formula 1) is -20 μm or more based on the measurement results of the unevenness height of the anti-glare film in the area adjacent to the anti-glare portion and the non-anti-glare portion using a specific measurement method.

Description

Technical Field

[0001] This invention relates to a substrate with an anti-glare film and a method for manufacturing the substrate with an anti-glare film. Background Technology

[0002] In image display devices (such as LCDs, OLEDs, and plasma displays) of various devices such as televisions, personal computers, smartphones, and mobile phones, visibility is reduced due to reflected images when indoor lighting such as fluorescent lamps or external light such as sunlight enters the display surface.

[0003] One method to suppress the reflection of external light is to place an anti-glare film with an uneven surface on the display surface of an image display device, causing external light to diffusely reflect and thus making the reflected image unclear.

[0004] As a method for forming an anti-glare film, a method is known to apply a coating liquid containing a silica precursor such as a hydrolytic condensate of alkoxysilane to a substrate and then calcining it. As a method for applying the coating liquid to a substrate, for example, a spraying method is known to apply the coating liquid in a mist using a two-fluid spray nozzle or the like (e.g., Patent Document 1), and an electrostatic coating method is known to apply the charged coating liquid to a grounded glass substrate by electrostatic attraction using an electrostatic coating apparatus equipped with an electrostatic coating gun (e.g., Patent Document 2).

[0005] When forming anti-glare films on the surfaces of various devices, sometimes areas without anti-glare films are partially provided, depending on the functions of these devices. For example, in recent years, there has been an increase in personal computers equipped with webcams, smartphones, and in-vehicle displays equipped with cameras to monitor the driver's state for purposes such as preventing drowsiness. In such devices, to prevent a decrease in camera resolution, it is required that the portion of the glass substrate that serves as the cover, corresponding to the camera's field of view, not have an anti-glare film formed.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2009-058640

[0009] Patent Document 2: International Publication No. 2015 / 186669 Summary of the Invention

[0010] One method for partially setting up areas where an anti-glare film is not formed is to cover the area with a protective film or other masking material and then apply a coating liquid. However, when forming an anti-glare film using this method, the coating liquid is difficult to adhere evenly near the masking material, resulting in an uneven anti-glare film. Sometimes this leads to deviations in anti-glare performance or problems with appearance.

[0011] Specifically, in the case of spraying, the coating liquid tends to accumulate excessively near the masking material. Therefore, sometimes the anti-glare film becomes too thick near the boundary between the area where the anti-glare film is formed (anti-glare section) and the area where the anti-glare film is not formed (non-anti-glare section).

[0012] Furthermore, when using electrostatic coating, the coating liquid does not easily adhere to the vicinity of the masking material, easily resulting in uncoated areas and areas with insufficient coating. Moreover, a significant amount of coating liquid tends to adhere around the masking material. Therefore, sometimes the non-anti-glare area becomes larger than the masking material area, the boundary between the anti-glare and non-anti-glare areas becomes unclear, or the thickness of the anti-glare film becomes uneven near the boundary with the non-anti-glare area.

[0013] In view of the above, the objective of the present invention is to provide a substrate with an anti-glare film in which an anti-glare film is formed substantially uniformly on a substrate near the boundary between the anti-glare portion and the non-anti-glare portion, and the boundary between the anti-glare portion and the non-anti-glare portion is clear.

[0014] To address the aforementioned issues, the present invention provides the following approach.

[0015] A substrate with an anti-glare film, comprising a substrate and an anti-glare film formed on at least a portion of a main surface of the substrate, having:

[0016] An anti-glare portion of the anti-glare film is formed on at least one main surface of the substrate; and

[0017] In the non-anti-glare portion where the anti-glare film is not formed on at least one main surface of the substrate,

[0018] Based on the measurement results of the unevenness height of the anti-glare film in the area adjacent to the anti-glare part and the non-anti-glare part using the following measurement method, the average value P obtained by using the following (Formula 1) is -20 μm or more.

[0019] The method for measuring the height of the convexity / concave section is as follows:

[0020] Set the measurement start position to the non-glare-proof part.

[0021] The measurement direction is set to be perpendicular to the boundary line between the anti-glare section and the non-anti-glare section, and from the non-anti-glare section toward the anti-glare section.

[0022] The unevenness of the anti-glare film was measured at intervals of 0.333 μm from the starting position on the non-anti-glare part to the anti-glare part.

[0023] The method for calculating the value P:

[0024] Let the measurement distance from the starting position to the measurement direction be x (μm), and the cumulative value of the unevenness height of the anti-glare film be y (μm), thus creating an x-y coordinate plane.

[0025] The point where the cumulative value y > 5 and the measurement distance x is the smallest is set as the end of the anti-glare film X1(x1, y1).

[0026] The measured distance x will be represented by a =The cumulative value y at (x1+100) a Let the point be A(x) a y a ),

[0027] The measured distance x will be represented by b =(x a The cumulative value y at +200) b Let the point be B(x) b y b ),

[0028] Draw a regression line between A and B.

[0029] Let the x-intercept of the above regression line be X2(x2, 0), and calculate the value P(μm) using the following (Equation 1).

[0030] x1-x2=P···(Equation 1)

[0031] A method for manufacturing a substrate with an anti-glare film, the substrate comprising: a substrate, and an anti-glare film formed on at least a portion of a main surface of the substrate, the manufacturing method comprising the following steps:

[0032] Prepare a coating composition comprising at least one of a silica precursor (A) and particles (C), and a liquid medium (B), wherein the liquid medium (B) comprises a liquid medium (B1) with a boiling point of less than 150°C, comprising more than 86% by mass of the liquid medium (B) in total.

[0033] A conductive film is formed on the surface of the masking material;

[0034] A portion of at least one main surface of the substrate is covered with a masking material having the conductive film formed thereon.

[0035] A coating film is formed by applying the above-mentioned coating composition to the above-mentioned substrate by using an electrostatic coating device to charge the coating composition and spraying it.

[0036] Remove the masking material from the substrate; and

[0037] An anti-glare film is formed by calcining the above coating.

[0038] According to one embodiment of the present invention, a substrate with an anti-glare film is provided in which the anti-glare film is formed substantially uniformly on the substrate near the boundary between the anti-glare portion and the non-anti-glare portion, and the boundary between the anti-glare portion and the non-anti-glare portion is clear.

[0039] Furthermore, according to one embodiment of the present invention, in the method for manufacturing a substrate with an anti-glare film, when forming the anti-glare film on the substrate, the anti-glare film can be formed substantially uniformly up to the vicinity of the area covered by the masking material. Thus, it is possible to manufacture a substrate with an anti-glare film in which the anti-glare film is formed substantially uniformly on the substrate near the boundary between the anti-glare portion and the non-anti-glare portion, and the boundary between the anti-glare portion and the non-anti-glare portion is clear. Attached Figure Description

[0040] Figure 1 This is a perspective view schematically illustrating an example of a substrate with an anti-glare film according to one embodiment of the present invention.

[0041] Figure 2 It is along Figure 1 The cross-sectional view of the section cut by line A-A'.

[0042] Figure 3 This is a schematic diagram illustrating the method for measuring the unevenness of the anti-glare film 5.

[0043] Figure 4 This is an example of a graph used in the calculation of the value P.

[0044] Figure 5 This is an example of a graph used in the calculation of the value P.

[0045] Figure 6 (a) to (d) are flowcharts illustrating a method for manufacturing a substrate with an anti-glare film according to one embodiment of the present invention.

[0046] Figure 7 The unevenness height of the anti-glare film on the substrate with anti-glare film in Example 3 will be plotted in an x-y orthogonal coordinate system to obtain a curve showing the relationship between the measured distance x and the unevenness height z.

[0047] Figure 8 The unevenness height of the anti-glare film on the substrate with anti-glare film in Example 3 will be plotted in an x-y orthogonal coordinate system to obtain a curve showing the relationship between the measured distance x and the cumulative value y of the unevenness height.

[0048] Figure 9The unevenness height of the anti-glare film on the substrate with anti-glare film in Example 5 will be plotted in an x-y orthogonal coordinate system to obtain a curve showing the relationship between the measured distance x and the unevenness height z.

[0049] Figure 10 The unevenness height of the anti-glare film on the substrate with anti-glare film in Example 5 will be plotted in an x-y orthogonal coordinate system to obtain a curve showing the relationship between the measured distance x and the cumulative value y of the unevenness height.

[0050] Figure 11 This is a photograph of the substrate with anti-glare film in Example 3, viewed from the top surface.

[0051] Figure 12 This is a photograph of the substrate with anti-glare film in Example 4, viewed from the top surface.

[0052] Figure 13 This is a photograph of the substrate with anti-glare film in Example 5, viewed from the top surface.

[0053] Figure 14 This is a photograph of the substrate with anti-glare film in Example 6, viewed from the top surface. Detailed Implementation

[0054] The following definitions apply to the scope of this specification and the patent claims.

[0055] "Transmittance" refers to the ability to transmit visible light.

[0056] "Mainly composed of silicon dioxide" means containing more than 90% by mass of SiO2.

[0057] "Silica precursor" refers to a substance that can be calcined to form a matrix with silica as the main component.

[0058] "Hydrolytically bonded groups to silicon atoms" refers to groups that can be converted into OH groups bonded to silicon atoms through hydrolysis.

[0059] "Scale-like particles" refer to particles with a flattened shape. The shape of the particles can be confirmed using a transmission electron microscope (hereinafter also referred to as TEM).

[0060] "Average particle size" refers to the particle size at the 50th percentile point in the cumulative volume distribution curve, where the total volume of the particle size distribution determined on a volume basis is set to 100%, i.e., the cumulative 50% diameter on a volume basis (D50). The particle size distribution is determined from the frequency distribution and cumulative volume distribution curves using a laser diffraction / scattering particle size distribution measuring device.

[0061] The "aspect ratio" refers to the ratio of the longest length of a particle to its thickness (longest length / thickness), and the "average aspect ratio" is the average of the aspect ratios of 50 randomly selected particles. The thickness of the particles was measured using an atomic force microscope (hereinafter also referred to as AFM), and the longest length was measured using a TEM.

[0062] In this specification, the term "~" indicating a numerical range is used to mean that the values ​​before and after it are the lower and upper limits. Unless otherwise specified, "~" in this specification shall have the same meaning below.

[0063] <Substrate with anti-glare film>

[0064] Figure 1 This is a perspective view schematically illustrating an example of a substrate with an anti-glare film according to one embodiment of the present invention. Additionally, Figure 2 It is along Figure 1 The cross-sectional view of the A-A' line in this embodiment. The substrate 1 with anti-glare film in this embodiment includes: substrate 3 and anti-glare film 5 formed on a portion of a first main surface 3A of substrate 3, the main surface 3A having an anti-glare portion 50 on which the anti-glare film 5 is formed and a non-anti-glare portion 30 on which the anti-glare film 5 is not formed.

[0065] When the surface of the substrate 1 with the anti-glare film 5 is designated as the upper surface of the substrate 1 with the anti-glare film, the anti-glare portion 50 is the area on the substrate 3 where the anti-glare film 5 is formed in the top view of the substrate 1 with the anti-glare film. Conversely, the non-anti-glare portion 30 is the area on the substrate 3 where the anti-glare film 5 is not formed in the top view of the substrate 1 with the anti-glare film. The non-anti-glare portion 30 can be formed, for example, by covering a portion of the substrate 3 with a masking material when forming the anti-glare film 5.

[0066] The anti-glare film 5 has a connecting region 40 at its end on the non-anti-glare portion 30 side. The surface of the anti-glare portion 50 and the surface of the non-anti-glare portion 30 are connected by the connecting region 40 located at the end of the anti-glare portion 50. The area adjacent to the anti-glare portion 50 and the non-anti-glare portion 30 refers to the vicinity of the boundary between the anti-glare portion 50 and the non-anti-glare portion 30, which includes the connecting region 40.

[0067] For a substrate with an anti-glare film according to one embodiment of the present invention, in the area adjacent to the anti-glare portion and the non-anti-glare portion, based on the measurement results of the unevenness height of the anti-glare film 5 obtained by the measurement method described below, the average value P calculated using the following (Formula 1) is -20 μm or more. This characteristic means that near the boundary between the anti-glare portion and the non-anti-glare portion, the anti-glare film is formed substantially uniformly on the substrate and the boundary between the anti-glare portion and the non-anti-glare portion is clear.

[0068] It should be noted that the anti-glare film 5 has an uneven surface, with some areas having large unevenness and others having small unevenness. Therefore, when observing the anti-glare film microscopically, its unevenness is not always apparent. Thus, it is difficult to determine the shape and unevenness of the anti-glare film near the connection area macroscopically based solely on the measured value of the unevenness. Therefore, in this invention, the unevenness of the anti-glare film is measured along the connection area from the non-anti-glare portion to the anti-glare portion, and a value P is calculated based on the relationship between the measured distance x and the cumulative value y of the unevenness, thereby analyzing the shape and unevenness near the connection area.

[0069] Figure 3 This is a schematic diagram illustrating the method for measuring the unevenness (film thickness) of the anti-glare film 5. In the region adjacent to the anti-glare portion 50 and the non-anti-glare portion 30, the unevenness of the anti-glare film 5 is measured from the measurement start position on the non-anti-glare portion 30 to the anti-glare portion 50. "Measurement from the measurement start position on the non-anti-glare portion 30 to the anti-glare portion 50" means that the unevenness is measured from the measurement start position on the non-anti-glare portion 30 to the anti-glare portion 50 via the connecting region 40. Furthermore, the unevenness is measured at intervals of 0.333 μm from the measurement start position on the non-anti-glare portion to the anti-glare portion.

[0070] Here, the measurement direction X is perpendicular to the boundary line between the anti-glare section 50 and the non-anti-glare section 30, and extends from the non-anti-glare section 30 toward the anti-glare section 50. It should be noted that if the boundary line has a curved portion, the measurement direction X only needs to be perpendicular to the tangent of the boundary line. For example, Figure 3 Since the anti-glare part in the middle is circular, the measurement direction X is perpendicular to the tangent T of the boundary line.

[0071] The height of the bump can be measured using a stylus-type profilometry system (manufactured by BRUKER, Dektak (registered trademark) XT), for example, under the conditions described in the examples.

[0072] During measurement, two points are selected in a flat area without any bumps or depressions on the non-anti-glare part for planarization. The distance between the two points used in the planarization process is preferably more than 100 μm, and preferably as wide as possible.

[0073] The method for calculating the value P based on the measurement results of the unevenness height of the anti-glare film obtained using the above measurement method is as follows.

[0074] Set the measurement distance x as the measurement distance (μm) from the measurement start position in the measurement direction.

[0075] Set the cumulative value y to the cumulative value (μm) of the unevenness height of the anti-glare film.

[0076] like Figure 4As shown, a graph was created by plotting the above measurement results on the x-y coordinate plane. The point where the cumulative value y > 5 and the measurement distance x is the smallest was set as the end of the anti-glare film X1(x1, y1). Furthermore, the measurement distance x was represented by... a =The cumulative value y at (x1+100) a Let the point be A(x) a y a ), which will represent the measured distance x b =(x a The cumulative value y at +200) b Let the point be B(x) b y b Draw a regression line between A and B. Set the x-intercept of the regression line to X2(x2, 0).

[0077] The value P(μm) is obtained from x1-x2=P···(Equation 1).

[0078] Here, the measurement interval for X is 0.333 μm, therefore x a =(x1+100), x b =(x a The value of (+200) may not necessarily match the value at the measurement point. Therefore, the measurement point closest to x1+100 is set as x. a The closest to x a The measurement point at +200 is set as x. b The measurements were taken.

[0079] Here, the cumulative value y increases monotonically with the increase of the measurement distance x. The "point where the cumulative value y > 5 and the measurement distance x is the smallest" is, in other words, the point where the cumulative value y is initially greater than 5 as the measurement distance x increases. In this embodiment, the position where the cumulative value y is initially greater than 5 as the measurement distance x increases (measurement distance x = x1) is regarded as the end of the anti-glare film 5 or near the connection area 40. On the graph, the point representing the cumulative value y1 at the measurement distance x = x1 is called the end of the anti-glare film X1 (x1, y1).

[0080] In addition, the "regression line between A and B" refers to the regression line obtained by using the least squares method for plotting the measurement results between A and B.

[0081] Ideally, assuming the anti-glare film has a steep end face and a constant height of its concavity and convexity, the value P is 0 μm or more. The steeper the end face, the larger the value P; conversely, the smoother the end face of the anti-glare film, the smaller the value P. The average value P is -20 μm or more, preferably 0 μm or more, more preferably 10 μm or more, and even more preferably 20 μm or more. Figure 4 This shows cases where the average value of P is above -20 μm. Figure 5This shows cases where the average value of P is less than -20 μm.

[0082] Here, the average value P refers to the average of all values ​​P calculated from multiple measurements of the unevenness height of the anti-glare film end face on a substrate with an anti-glare film. From the viewpoint of value deviation, it is preferable to perform at least three measurements of the unevenness height of the anti-glare film and calculations of the value P for a single substrate with an anti-glare film.

[0083] By setting P within the aforementioned range, a substrate 1 with an anti-glare film can be obtained where, near the boundary between the anti-glare portion 50 and the non-anti-glare portion 30, the anti-glare film 5 is formed substantially uniformly on the main surface of the substrate 3, and the boundary between the anti-glare portion 50 and the non-anti-glare portion 30 is clear. "The anti-glare film 5 is formed substantially uniformly on the substrate 3" means that the slope formed by the connecting region 40 relative to the surface of the substrate 3 of the non-anti-glare portion 30 is steep, and the unevenness near the connecting region 40 of the anti-glare film 5 is the same as the unevenness of other parts of the anti-glare film 5. This results in a clearer appearance of the boundary between the anti-glare portion 50 and the non-anti-glare portion 30.

[0084] It should be noted that the maximum value of the preferred value P is 0 μm or more, and the minimum value is -70 μm or more.

[0085] For example, when forming an anti-glare film, if the coating liquid accumulates excessively near the masking material, the unevenness near the bonding area of ​​the anti-glare film can easily become too large. Furthermore, sometimes areas with excessive unevenness appear white and cloudy, damaging the appearance of the bonding area.

[0086] Furthermore, when forming the anti-glare film 5, if uncoated areas or areas with low coating amount are generated near the masking material, the slope formed by the connecting area 40 relative to the surface of the substrate 3 of the non-anti-glare portion 30 tends to become gentle. If the slope of the connecting area 40 is gentle, the boundary between the anti-glare portion 50 and the non-anti-glare portion 30 tends to become unclear because the unevenness of the anti-glare film 5 decreases towards the end near the non-anti-glare portion. In addition, because the gentle slope creates areas with less unevenness at the ends of the anti-glare film 5 than other areas, the areas with relatively larger unevenness around these areas sometimes appear white and cloudy due to the unevenness difference. Therefore, the appearance of the boundary between the anti-glare portion 50 and the non-anti-glare portion 30 is sometimes impaired.

[0087] In addition, if the thickness of the anti-glare film 5 is not uniform, the anti-glare performance and other qualities of the substrate 1 with the anti-glare film may deviate.

[0088] (Substrate)

[0089] As a substrate, it is acceptable as long as it can transmit visible light, and it is preferably transparent. Transparency of the substrate means that it transmits an average of 80% or more of the light in the 400–1100 nm wavelength region, i.e., the average transmittance in the 400–1100 nm wavelength region is 80% or more. The average transmittance in the 400–1100 nm wavelength region is a value measured using an integrating sphere.

[0090] Materials used as substrates include, for example, glass and resin.

[0091] Examples of glass types include soda-lime glass, borosilicate glass, aluminosilicate glass, and alkali-free glass.

[0092] Examples of resins include polyethylene terephthalate, polycarbonate, cellulose triacetate, and polymethyl methacrylate.

[0093] Examples of substrate forms include plates and films.

[0094] The first main surface 3A of the substrate into which the anti-glare film is formed can be smooth or uneven. For the usefulness of providing the anti-glare film, smoothness is preferred. The arithmetic mean roughness Ra of the first main surface 3A is preferably 10 nm or less, more preferably 5 nm or less, further preferably 2 nm or less, and particularly preferably 1 nm or less. Ra, as referred to herein, is a value measured in atomic force microscopy (AFM) mode.

[0095] The shape of the substrate 3 can be as follows: Figure 1 The flat shape shown in the illustration can also be a curved shape. Recently, devices with curved display surfaces for image display devices have appeared in various devices equipped with image display devices (televisions, personal computers, smartphones, and car navigation systems, etc.). Substrate 3, which is substrate 1 with a curved shape and an anti-glare film, is useful for such image display device applications.

[0096] When the substrate 3 has a curved surface, the surface of the substrate 3 can be entirely composed of a curved surface, or it can be composed of curved portions and flat portions. Examples of a surface that is entirely composed of a curved surface include cases where the substrate 3 is bent about a single straight line as an axis and with a certain radius of curvature, cases where the substrate 3 is bent about multiple straight lines as axes and with a certain radius of curvature, and cases where the radius of curvature changes regardless of the number of straight lines serving as axes.

[0097] It should be noted that the surface referred to here is a macroscopic surface of negligible degree in the observation area observed using a laser microscope.

[0098] When the substrate 3 has a curved surface, the radius of curvature of the curved surface (hereinafter also referred to as "R") can be appropriately set according to the application of the substrate 1 with the anti-glare film, the type of substrate 3, etc., and is not particularly limited. It is preferably 25,000 mm or less, more preferably 10 to 5,000 mm, and particularly preferably 50 to 3,000 mm. If R is below the upper limit value mentioned above, the design flexibility is superior compared to a flat plate. If R is above the lower limit value mentioned above, the anti-glare film can also be uniformly formed on the curved surface.

[0099] As the substrate 3, a glass plate is preferred.

[0100] The glass sheet can be a smooth glass sheet formed using methods such as float glass, melting glass, and downdrawing glass, or it can be patterned glass with an uneven surface formed using methods such as rolling glass. Furthermore, it can be not only a flat glass sheet, but also a glass sheet with a curved surface. When the glass sheet has a curved surface, the preferred radius of curvature of the curved surface is the same as described above.

[0101] There is no particular limitation on the thickness of the glass plate. For example, a glass plate with a thickness of 10 mm or less can be used. The thinner the glass, the lower the light absorption is suppressed, and therefore it is preferred for applications where the purpose is to improve transmittance. In addition, the thinner the glass, the more it helps to reduce the weight of the substrate 1 with the anti-glare film.

[0102] The glass sheet is preferably a tempered glass sheet. A tempered glass sheet is a glass sheet that has undergone a strengthening process. The strength of the glass can be increased through strengthening, for example, by reducing the sheet thickness while maintaining strength.

[0103] However, in this invention, glass plates other than tempered glass plates may also be used, and the appropriate setting may be made according to the intended use of the substrate 1 with anti-glare film, etc.

[0104] As a strengthening treatment, it is generally known to form a compressive stress layer on the surface of a glass plate. The compressive stress layer on the surface of the glass plate increases its strength against scratches and impacts. Representative methods for forming a compressive stress layer on the surface of a glass plate include air-cooling strengthening (physical strengthening) and chemical strengthening.

[0105] In the air-cooling strengthening method, the surface of a glass plate heated to near its softening point (e.g., 600–700°C) is rapidly cooled using air cooling or similar methods. This creates a temperature difference between the surface and interior of the glass plate, generating compressive stress on the surface layer.

[0106] In chemical strengthening, a glass plate is immersed in molten salt at a temperature below its strain point, which exchanges ions (e.g., sodium ions) on the glass surface with ions with larger ionic radii (e.g., potassium ions). This generates compressive stress on the glass surface.

[0107] If the thickness of the glass plate becomes thinner (e.g., less than 2 mm), it is not easy to generate a temperature difference between the inside and the surface of the glass plate in the air-cooled strengthening method, so the glass plate cannot be sufficiently strengthened. Therefore, the chemical strengthening method is preferred.

[0108] There are no particular limitations on the composition of the glass sheet after chemical strengthening treatment, as long as it has a chemically strengthening component; various compositions of glass sheets can be used. Examples include soda-lime glass, aluminosilicate glass, borosilicate glass, lithium aluminosilicate glass, borosilicate glass, and various other types of glass. From the perspective of ease of chemical strengthening, the glass composition, expressed as a molar percentage based on oxides, preferably contains 56–75% SiO2, 1–20% Al2O3, 8–22% Na2O, 0–10% K2O, 0–14% MgO, 0–5% ZrO2, and 0–10% CaO. Among these, aluminosilicate glass is preferred.

[0109] The thickness of the chemically strengthened glass plate is preferably 0.4 to 3 mm, and particularly preferably 0.5 to 2.5 mm. If the thickness of the chemically strengthened glass plate is below the upper limit of the above range, the substrate 1 with the anti-glare film is lightweight; if it is above the lower limit of the above range, the substrate 1 with the anti-glare film has excellent strength.

[0110] It should be noted that the thickness of the glass plate remains unchanged before and after chemical strengthening. That is, the thickness of the glass plate that has undergone chemical strengthening is the same as the thickness of the chemically strengthened glass plate (i.e., the glass plate after chemical strengthening).

[0111] The physical and chemical strengthening treatments of the glass described above can be performed before or after the formation of the anti-glare film on the glass surface.

[0112] The substrate 3 may also have a functional layer on the surface of the substrate body.

[0113] The substrate is the same as the example given above as substrate 3.

[0114] As functional layers, examples include primer layers, adhesion improvement layers, and protective layers.

[0115] The primer layer functions as an alkali barrier layer and a broadband low-refractive-index layer. Preferably, the primer layer is formed by applying a primer coating composition containing a hydrolysate of alkoxysilane (sol-gel silica) to the substrate.

[0116] (Anti-glare film)

[0117] Anti-glare film refers to a film used to suppress surface reflection. For example, in various image display devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs), when external light such as indoor lighting (fluorescent lamps, etc.) and sunlight is reflected onto the display surface, visibility is reduced due to image reflection. As a method to suppress the reduction in visibility caused by reflected images, there is a so-called anti-glare treatment that forms an anti-glare layer (hereinafter also referred to as an AG layer) on the display surface to diffuse external light.

[0118] The anti-glare film only needs to have an uneven surface to achieve an anti-glare effect, and the shape of the uneven surface is not particularly limited. For example, the arithmetic mean roughness Ra of the surface of the anti-glare film is preferably 0.05 μm or more, more preferably 0.10 to 0.70 μm, and even more preferably 0.15 to 0.50 μm.

[0119] If the arithmetic mean roughness Ra of the anti-glare film surface is 0.05 μm or higher, the anti-glare effect can be fully achieved. If the arithmetic mean roughness Ra of the anti-glare film surface is 0.70 μm or lower, which is the upper limit of the above range, the reduction in image contrast is sufficiently suppressed. It should be noted that the unevenness parameters are measured using a surface roughness measuring device (SURFCOM1500-DX).

[0120] The maximum surface roughness Rz of the anti-glare film is preferably 0.1 to 5.0 μm, more preferably 0.2 to 4.5 μm, and even more preferably 0.3 to 4.0 μm. If the maximum surface roughness Rz of the anti-glare film is above the lower limit of the above range, the anti-glare effect is fully realized. If the maximum surface roughness Rz of the anti-glare film is below the upper limit of the above range, the reduction in image contrast is sufficiently suppressed.

[0121] The refractive index of the anti-glare film 5 is preferably 1.36 to 1.51, more preferably 1.40 to 1.49, and particularly preferably 1.43 to 1.46. If the refractive index of the anti-glare film 5 is below the upper limit of the above range, the reflectivity of external light on the surface of the anti-glare film 5 is lower, and the anti-glare effect is better. If the refractive index of the anti-glare film 5 is above the lower limit of the above range, the density of the anti-glare film 5 is sufficiently high, and the adhesion to the substrate 3 such as the glass plate is excellent.

[0122] The refractive index of the anti-glare film 5 can be adjusted by the material of the substrate of the anti-glare film 5, the porosity of the anti-glare film 5, and by adding a substance with any refractive index to the substrate. For example, the refractive index can be reduced by increasing the porosity of the anti-glare film 5. In addition, the refractive index of the anti-glare film 5 can be reduced by adding a substance with a low refractive index (such as solid silica particles and hollow silica particles) to the substrate.

[0123] The material of the anti-glare film 5 can be appropriately set considering factors such as refractive index. Examples of materials for the anti-glare film 5 with a refractive index of 1.36 to 1.51 include silicon dioxide.

[0124] The preferred anti-glare film 5 contains silicon dioxide and is primarily composed of silicon dioxide. If silicon dioxide is the primary component, the refractive index (reflectivity) of the anti-glare film 5 tends to decrease. Furthermore, the anti-glare film 5 exhibits good chemical stability. Additionally, when the substrate 3 is made of glass, it provides good adhesion to the substrate 3.

[0125] When silicon dioxide is the main component, the anti-glare film 5 may be composed of only silicon dioxide, or it may contain a small amount of components other than silicon dioxide. Examples of such components include compounds selected from one or more ions and / or oxides of the following elements: Li, B, C, N, F, Na, Mg, Al, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Sr, Y, Zr, Nb, Ru, Pd, Ag, In, Sn, Hf, Ta, W, Pt, Au, Bi, and the lanthanides.

[0126] As an example of an anti-glare film 5, an anti-glare film formed from a coating composition comprising at least one of a silica precursor (A) and particles (C), and a liquid medium (B) can be provided. The coating composition may, as needed, include other binders (D) and other additives (E) besides the silica precursor (A).

[0127] When the coating composition contains a silica precursor (A), the matrix of the anti-glare film 5 is mainly composed of silica derived from the silica precursor (A). The anti-glare film 5 may be composed of particles (C). In this case, the particles (C) are preferably silica particles. The anti-glare film 5 may also be a film obtained by dispersing the particles (C) in the aforementioned matrix.

[0128] The method for forming the anti-glare film 5 using the coating composition is described in detail below.

[0129] Examples of anti-glare films with silica as the main component include anti-glare films formed from a coating composition containing the aforementioned silica precursor (A), anti-glare films formed from a coating composition containing silica particles as the aforementioned particles (C), and anti-glare films formed from a coating composition containing the aforementioned silica precursor (A) and silica particles as the aforementioned particles (C).

[0130] The 60° specular gloss of the surface of the anti-glare film 5 is preferably 130% or less, more preferably 120% or less, and even more preferably 110% or less. The 60° specular gloss of the surface of the anti-glare film 5 is an indicator of the anti-glare effect. If the 60° specular gloss is below the above-mentioned upper limit, the anti-glare effect can be fully utilized.

[0131] The "60° specular gloss" is measured using the method described in JIS Z8741:1997 (ISO2813:1994) without eliminating backside reflection (i.e., the side opposite to the side with the anti-glare film).

[0132] Furthermore, in the substrate 1 with anti-glare film according to one embodiment of the present invention, the haze of the anti-glare portion 50 is preferably 30% or less, more preferably 20% or less, and particularly preferably 10% or less. If the haze is below the upper limit of the above range, the transmittance of light from the side opposite to the anti-glare portion 50 is more excellent.

[0133] “Haze” was measured using the method described in JIS K7136:2000 (ISO14782:1999).

[0134] In the anti-glare section 50, the glare index value S, measured by placing the substrate 1 with the anti-glare film on an Apple iPhone 4 with the surface having an uneven structure (the surface on the side of the anti-glare film 5) facing upwards using an iScale ISC-A manufactured by I-system Co., Ltd., is preferably less than 100, more preferably less than 80, and particularly preferably less than 60. The smaller the glare index value S, the more glare is suppressed.

[0135] <Method for manufacturing a substrate with an anti-glare film>

[0136] A method for manufacturing a substrate with an anti-glare film according to one embodiment of the present invention comprises the following steps:

[0137] The process of preparing a coating composition (hereinafter also referred to as the coating composition preparation process) includes at least one of a silica precursor (A) and particles (C), and a liquid medium (B), wherein the liquid medium (B) includes a liquid medium (B1) with a boiling point of less than 150°C, comprising more than 86% by mass of the liquid medium (B) in total amount.

[0138] The process of forming a conductive film on the surface of a masking material (hereinafter also referred to as the conductive film forming process);

[0139] The process of covering a portion of at least one main surface of the above-mentioned substrate with a masking material having the above-mentioned conductive film formed thereon (hereinafter also referred to as the masking process);

[0140] The process of applying the above-mentioned coating composition to a substrate by using an electrostatic coating device to charge it and spraying it to form a coating film (hereinafter also referred to as the coating process);

[0141] The process of removing the masking material from the substrate (hereinafter also referred to as the masking removal process); and

[0142] The process of forming an anti-glare film by calcining the above coating (hereinafter also referred to as the calcination process).

[0143] The manufacturing method described above may include a step of forming a functional layer on the surface of the substrate body to produce a substrate before forming the anti-glare film, or a step of performing known post-processing after forming the anti-glare film.

[0144] [Preparation process of coating composition]

[0145] The coating composition comprises at least one of a silica precursor (A) and particles (C), and a liquid medium (B).

[0146] When the coating composition does not contain silica precursor (A) but contains particles (C), the average particle size of the particles (C) is preferably 30 nm or less.

[0147] The coating composition may include other binders (D) and other additives (E) other than the silica precursor (A) as needed, without impairing the effects of the present invention.

[0148] (Silica precursor (A))

[0149] Examples of silica precursors (A) include silane compounds (A1) and their hydrolytic condensates having hydrocarbon groups and hydrolyzable groups bonded to silicon atoms, alkoxysilanes (excluding silane compounds (A1)) and their hydrolytic condensates (sol-gel silica), silazanes, etc.

[0150] In silane compounds (A1), the hydrocarbon group bonded to the silicon atom can be a monovalent hydrocarbon group bonded to one silicon atom or a divalent hydrocarbon group bonded to two silicon atoms. Examples of monovalent hydrocarbon groups include alkyl, alkenyl, and aryl groups. Examples of divalent hydrocarbon groups include alkylene, alkenyl, and aryl groups.

[0151] The hydrocarbon group can be a group consisting of one or more of the following: -O-, -S-, -CO-, and -NR'- (where R' is a hydrogen atom or a monovalent hydrocarbon group) between carbon atoms.

[0152] Examples of hydrolyzable groups that bond to silicon atoms include alkoxy, acyloxy, ketoxime, alkenoxy, amino, aminooxy, amide, isocyanate, and halogen atoms. Among these, alkoxy, isocyanate, and halogen atoms (especially chlorine atoms) are preferred from the perspective of balancing the stability of silane compounds (Al) with the ease of hydrolysis.

[0153] The preferred alkoxy group is one with 1 to 3 carbon atoms, and more preferably a methoxy or ethoxy group.

[0154] When a silane compound (A1) contains multiple hydrolyzable groups, the hydrolyzable groups can be the same group or different groups. From the perspective of easy availability, the same group is preferred.

[0155] Examples of silane compounds (A1) include compounds represented by formula (I) described later, alkyl alkoxysilanes (such as methyltrimethoxysilane and ethyltriethoxysilane), vinyl alkoxysilanes (such as vinyltrimethoxysilane and vinyltriethoxysilane), epoxy alkoxysilanes (such as 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-epoxypropoxypropyltrimethoxysilane, 3-epoxypropoxypropylmethyldiethoxysilane and 3-epoxypropoxypropyltriethoxysilane), and acryloyloxy alkoxysilanes (such as 3-acryloyloxypropyltrimethoxysilane).

[0156] As for the silane compound (A1), considering that it is not easy to cause cracks or peeling of the anti-glare film 5 even if the unevenness is thick, the compound represented by the following formula (I) is preferred.

[0157] R 3－p L p Si-Q-SiL p R 3－p ···(I)

[0158] In formula (I), Q is a divalent hydrocarbon group (the carbon atoms may have one or more groups selected from -O-, -S-, -CO- and -NR'- (where R' is a hydrogen atom or a monovalent hydrocarbon group)). Examples of divalent hydrocarbon groups can be given above.

[0159] As for Q, considering that it is easy to obtain and that even if the unevenness is thick, cracks or peeling of the anti-glare film 5 are not likely to occur, it is preferably an alkylene group with 2 to 8 carbon atoms, and more preferably an alkylene group with 2 to 6 carbon atoms.

[0160] In formula (I), L is a hydrolyzable group. Examples of hydrolyzable groups can be found above, and the preferred method is also the same.

[0161] R can be a hydrogen atom or a monovalent hydrocarbon group. Examples of monovalent hydrocarbon groups mentioned above can be cited.

[0162] p is an integer from 1 to 3. From the perspective of not slowing down the reaction rate too much, p is preferably 2 or 3, and particularly preferably 3.

[0163] Examples of alkoxysilanes (excluding the aforementioned silane compounds (A1)) include tetraalkoxysilanes (tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane, etc.), alkoxysilanes having a perfluoropolyether group (perfluoropolyether triethoxysilane, etc.), and alkoxysilanes having a perfluoroalkyl group (perfluoroethyl triethoxysilane, etc.).

[0164] The hydrolysis and condensation of silane compounds (A1) and alkoxysilanes (excluding silane compounds (A1)) can be carried out by known methods.

[0165] For example, in the case of tetraalkoxysilane, water at a molar ratio of more than 4 times that of tetraalkoxysilane and an acid or base as a catalyst are used.

[0166] Examples of acids include inorganic acids (HNO3, H2SO4, and HCl, etc.) and organic acids (formic acid, oxalic acid, monochloroacetic acid, dichloroacetic acid, and trichloroacetic acid, etc.). Examples of bases include ammonia, sodium hydroxide, and potassium hydroxide. As a catalyst, an acid is preferred from the perspective of the long-term preservation of the hydrolysis condensate of silane compounds (Al).

[0167] As a precursor to silica (A), it can be used alone or in combination with two or more other precursors.

[0168] From the viewpoint of preventing cracks and peeling of the anti-glare film 5, the silica precursor (A) preferably contains either or both of a silane compound (A1) and its hydrolysate condensate.

[0169] From the viewpoint of the wear resistance of the anti-glare film 5, the silica precursor (A) preferably contains any one or both of tetraalkoxysilane and its hydrolysate.

[0170] The silica precursor (A) is particularly preferably composed of any or both of a silane compound (A1) and its hydrolysis condensate, and any or both of a tetraalkoxysilane and its hydrolysis condensate.

[0171] (Liquid medium (B))

[0172] The liquid medium (B) dissolves or disperses the silica precursor (A) when the coating composition contains silica precursor (A), and disperses the particles (C) when the coating composition contains particles (C). When the coating composition contains both silica precursor (A) and particles (C), the liquid medium (B) can function as both a solvent or dispersion medium for dissolving or dispersing the silica precursor (A) and a dispersion medium for dispersing the particles (C).

[0173] The liquid medium (B) includes at least a liquid medium (B1) with a boiling point below 150°C. The boiling point of the liquid medium (B1) is preferably 50 to 145°C, more preferably 55 to 140°C.

[0174] If the boiling point of the liquid medium (B1) is below 150°C, the film obtained by applying the coating composition to the substrate 3 using an electrostatic coating apparatus equipped with an electrostatic coating gun with a rotating atomizing head and then calcining it has better anti-glare performance. If the boiling point of the liquid medium (B1) is above the lower limit of the above range, the coating composition droplets can form an uneven structure while maintaining the droplet shape sufficiently after adhering to the substrate 3.

[0175] Examples of liquid media (B1) include water, alcohols (methanol, ethanol, isopropanol, n-butanol, isobutanol, and 1-pentanol, etc.), ketones (acetone, methyl ethyl ketone, and methyl isobutyl ketone, etc.), and ethers (tetrahydrofuran and 1,4-diethyl ether). Alkane, etc.), cellosols (methyl cellosol and ethyl cellosol, etc.), esters (methyl acetate and ethyl acetate, etc.), and diol ethers (ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, etc.).

[0176] Liquid medium (B1) can be used alone or in combination of two or more.

[0177] The liquid medium (B) may, as needed, further include other liquid media besides the liquid medium (B1), namely liquid media with a boiling point exceeding 150°C.

[0178] Other liquid media include, for example, alcohols, ketones, ethers, cellosols, esters, diol ethers, nitrogen-containing compounds, and sulfur-containing compounds.

[0179] Examples of alcohols include diacetone alcohol, 1-hexanol, and ethylene glycol.

[0180] Examples of nitrogen-containing compounds include N,N-dimethylacetamide, N,N-dimethylformamide, and N-methylpyrrolidone.

[0181] Examples of diol ethers include ethylene glycol monobutyl ether.

[0182] Examples of sulfur-containing compounds include dimethyl sulfoxide.

[0183] Other liquid media can be used alone or in combination of two or more.

[0184] Since the hydrolysis of alkoxysilanes and the like in the silica precursor (A) requires water, as long as no replacement of the liquid medium occurs after hydrolysis, the liquid medium (B) will contain at least water as the liquid medium (B1).

[0185] In this case, the liquid medium (B) can be water alone, or it can be a mixture of water and other liquids. The other liquid can be any liquid medium other than water (B1), such as alcohols, ketones, ethers, cellosolves, esters, diol ethers, nitrogen-containing compounds, and sulfur-containing compounds. Among these, alcohols are preferred as the solvent for the silica precursor (A), and methanol, ethanol, isopropanol, and butanol are particularly preferred.

[0186] (particle(C))

[0187] The particles (C) can form an anti-glare film either alone or together with a matrix from the silica precursor (A).

[0188] When the coating composition contains particles (C) but not silica precursor (A), the average particle size of the particles (C) is preferably 30 nm or less.

[0189] As particles (C), examples include scale-like particles (C1) and other particles besides scale-like particles (C1) (C2), etc.

[0190] Scale-like particles (C1):

[0191] The average aspect ratio of the flake-like particles (C1) is preferably 50 to 650, more preferably 100 to 350, and even more preferably 170 to 240. If the average aspect ratio of the flake-like particles (C1) is 50 or more, cracking and peeling of the anti-glare film can be sufficiently suppressed even with a high degree of unevenness. If the average aspect ratio of the flake-like particles (C1) is 650 or less, the dispersion stability in the coating composition becomes good.

[0192] The average particle size of the flake-like particles (C1) is preferably 0.08 to 0.42 μm, more preferably 0.17 to 0.21 μm. If the average particle size of the flake-like particles (C1) is 0.08 μm or more, cracking and peeling of the anti-glare film are sufficiently suppressed even with a high degree of unevenness. If the average particle size of the flake-like particles (C1) is 0.42 μm or less, the dispersion stability in the coating composition becomes good.

[0193] Examples of flake-like particles (C1) include flake-like silica particles, flake-like alumina particles, flake-like titanium dioxide, and flake-like zirconium oxide. Among these, flake-like silica particles are preferred from the perspective of suppressing the increase in the refractive index of the film and reducing the reflectivity.

[0194] Flake-like silica particles are secondary silica particles formed by thin sheets of primary silica particles or multiple thin sheets of primary silica particles that are oriented parallel to each other and overlap. Secondary silica particles typically have a layered structure.

[0195] Flake-like silica particles can be either primary silica particles or secondary silica particles, or both.

[0196] The thickness of the primary silica particles is preferably 0.001 to 0.1 μm. If the thickness of the primary silica particles is within the above range, one or more overlapping flake-like secondary silica particles can be formed by aligning the surfaces of the particles in parallel to each other.

[0197] The ratio of the minimum length to the thickness of the primary silica particles (minimum length / thickness) is preferably 2 or more, more preferably 5 or more, and even more preferably 10 or more.

[0198] The thickness of the secondary silica particles is preferably 0.001–3 μm, more preferably 0.005–2 μm.

[0199] The ratio of the minimum length to the thickness of the secondary silica particles (minimum length / thickness) is preferably 2 or more, more preferably 5 or more, and even more preferably 10 or more.

[0200] Silica secondary particles preferably exist independently without fusing together.

[0201] The SiO2 purity of the flake-shaped silica particles is preferably 95% by mass or more, and more preferably 99% by mass or more.

[0202] The coating composition can be prepared using a powder that is an aggregate of multiple flake-like silica particles, or a dispersion formed by dispersing the powder in a liquid medium. The silica concentration in the dispersion is preferably 1–80% by mass.

[0203] The powder or dispersion contains not only flake-shaped silica particles, but also sometimes amorphous silica particles generated during the manufacture of the flake-shaped silica particles.

[0204] Flake-like silica particles are obtained, for example, by breaking down and dispersing silica tertiary particles (hereinafter also referred to as silica condensates) that are formed by agglomerating and irregularly overlapping flake-like silica particles into a condensate shape with gaps.

[0205] Although amorphous silica particles represent a degree of micronization within silica aggregates, they are not micronized into individual flake-like particles; rather, they form a mass of multiple flake-like silica particles. The presence of amorphous silica particles can reduce the density of the formed anti-glare film, potentially leading to cracking and film peeling. Therefore, a lower content of amorphous silica particles in the powder or dispersion is preferable.

[0206] Amorphous silica particles and silica aggregates both appear black in TEM observations. On the other hand, flake-like primary or secondary silica particles appear transparent or translucent in TEM observations.

[0207] Commercially available flake silica particles or manufactured flake silica particles can be used.

[0208] As flake-shaped silica particles, flake-shaped silica particles manufactured by the manufacturing method described in Japanese Patent Application Publication No. 2014-94845 are preferred. This manufacturing method includes the following steps: acid treatment of silica powder containing silica aggregates formed by the aggregation of flake-shaped silica particles at pH 2 or lower; alkaline treatment of the acid-treated silica powder at pH 8 or higher to dissolve the silica aggregates; and wet disintegration of the alkaline-treated silica powder to obtain flake-shaped silica particles. According to this manufacturing method, compared with known manufacturing methods (e.g., the method described in Japanese Patent No. 4063464), it is possible to obtain powders or dispersions with suppressed amorphous silica particle generation and low amorphous silica particle content in the manufacturing process.

[0209] Particle (C2):

[0210] Other particles (C2) besides flaky particles (C1) include metal oxide particles, metal particles, pigment particles, and resin particles.

[0211] Examples of materials that can be considered as metal oxide particles include Al2O3, SiO2, SnO2, TiO2, ZrO2, ZnO, CeO2, and Sb-containing SnO. X Materials include (ATO), Sn-containing In2O3 (ITO), and RuO2. Since silicon dioxide is preferably used as the substrate in the anti-glare film of the present invention, SiO2 with the same refractive index as the substrate is preferred in this case.

[0212] Materials that can be used as metallic particles include metals (such as Ag and Ru) and alloys (such as AgPd and RuAu).

[0213] As pigment particles, examples include inorganic pigments (such as titanium black and carbon black) and organic pigments.

[0214] Examples of materials that can be used as resin particles include acrylic resin, polystyrene, and melamine resin.

[0215] Examples of particle (C2) shapes include spherical, elliptical, needle-like, plate-like, rod-like, conical, cylindrical, cubic, cuboid, diamond-like, star-like, amorphous, or combinations of these shapes. Other particles can exist independently, in chains, or condense.

[0216] The particle (C2) can be a solid particle, a hollow particle, a porous particle, or other open-pore particles.

[0217] As particles (C2), spherical silica particles, rod-shaped silica particles, and needle-shaped silica particles are preferred (excluding flake-shaped silica particles). From the perspective that the haze of the substrate 1 with the anti-glare film is sufficiently increased and the 60° specular gloss of the surface of the anti-glare film 5 is sufficiently reduced, thereby maximizing the anti-glare effect, spherical silica particles are preferred, and porous spherical silica particles are more preferred.

[0218] The average particle size of the particles (C2) is preferably 0.3 to 2 μm, more preferably 0.5 to 1.5 μm. If the average particle size of the particles (C2) is 0.3 μm or more, the anti-glare effect can be fully achieved. If the average particle size of the particles (C2) is 2 μm or less, the dispersion stability in the coating composition becomes good.

[0219] The preferred BET specific surface area of ​​porous spherical silica particles is 200–300 m². 2 / g.

[0220] The pore volume of the porous spherical silica particles is preferably 0.5–1.5 cm³. 3 / g.

[0221] Commercially available porous spherical silica particles include the Lightstar (registered trademark) series manufactured by Nissan Chemical Co., Ltd.

[0222] Particle (C) can be used alone or in combination with two or more types.

[0223] The particles (C) preferably include flake-like particles (C1), and may further include particles (C2). By including flake-like particles (C1), the haze of the anti-glare film 5 is improved, resulting in superior anti-glare performance. In addition, compared with particles (C2), including flake-like particles (C1) makes it less prone to cracking and film peeling when the unevenness of the anti-glare film 5 is thickened.

[0224] (Adhesive(D))

[0225] Examples of adhesives (D) (excluding silica precursors (A)) include inorganic substances, resins, etc., that are dissolved or dispersed in a liquid medium (B).

[0226] As inorganic materials, examples include metal oxide precursors other than silicon dioxide (metals: titanium and zirconium, etc.).

[0227] Examples of resins include thermoplastic resins, thermosetting resins, and UV-curing resins.

[0228] (Additive (E))

[0229] Examples of additives (E) include, for example, organic compounds (E1) having polar groups, ultraviolet absorbers, infrared reflectors, infrared absorbers, antireflective agents, surfactants for improving leveling properties, and metal compounds for improving durability.

[0230] When a coating composition contains particles (C), by including an organic compound (E1) with polar groups in the coating composition, it is possible to suppress the aggregation of particles (C) in the coating composition caused by electrostatic forces.

[0231] As an organic compound (E1) with polar groups, from the perspective of inhibiting particle (C) aggregation, it is preferred to be an organic compound having hydroxyl and / or carbonyl groups in the molecule, more preferably an organic compound having one or more organic compounds selected from hydroxyl, aldehyde (-CHO), ketone (-C(=O)-), ester bond (-C(=O)O-) and carboxyl (-COOH) in the molecule, and even more preferably an organic compound having one or more organic compounds selected from carboxyl, hydroxyl, aldehyde and ketone in the molecule.

[0232] Examples of organic compounds (E1) with polar groups include unsaturated carboxylic acid polymers, cellulose derivatives, organic acids (excluding unsaturated carboxylic acid polymers), and terpenoids. An organic compound (E1) can be used alone or in combination with two or more.

[0233] Polyacrylic acid is an example of an unsaturated carboxylic acid polymer.

[0234] Polyhydroxyalkyl cellulose is an example of a cellulose derivative.

[0235] Examples of organic acids (excluding unsaturated carboxylic acid polymers) include formic acid, oxalic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, citric acid, tartaric acid, and maleic acid.

[0236] It should be noted that when an organic acid is used as a catalyst in the hydrolysis of alkoxysilanes, etc., the organic acid is also included in the organic acid as an organic compound (E1).

[0237] Terpenes refer to compounds with isoprene (C5H8) as their constituent unit. n Hydrocarbons composed of (where n is an integer greater than or equal to 1). Terpenes are terpenes that have functional groups derived from terpenes. Terpenes also include terpenes with varying degrees of unsaturation.

[0238] It should be noted that terpenoid compounds sometimes function as liquid media, but as "(C5H8) compounds with isoprene as the building block". n Terpenoids, which are composed of hydrocarbons, are terpenoid derivatives and not liquid media.

[0239] Examples of terpene derivatives include terpene alcohols (α-terpineol, terpinene 4-ol, L-menthol, (±)citronellol, myrtol, camphenol, nerol, farnesol, and phytol, etc.), terpene aldehydes (citral, β-cyclocitral, and perillaldehyde, etc.), terpene ketones (camphor and β-ionone, etc.), terpene carboxylic acids (citronellolic acid and abietic acid, etc.), and terpene esters (terpineyl acetate and menthyl acetate, etc.).

[0240] Examples of surfactants used to improve leveling properties include silicone oil-based and acrylic-based surfactants.

[0241] Zirconium chelates, titanium chelates, and aluminum chelates are preferred metal compounds for improving durability. Examples of zirconium chelates include zirconium tetraacetylacetone and zirconium tributoxystearate.

[0242] (Composition of the coating composition)

[0243] When the coating composition contains a silica precursor (A) and particles (C), the total content of the silica precursor (A) and particles (C) in the coating composition is preferably 30 to 100% by mass of the solid content (100% by mass) of the coating composition (wherein, the silica precursor (A) is converted to SiO2), and more preferably 40 to 100% by mass.

[0244] If the total content of silica precursor (A) and particles (C) is above the lower limit of the above range, the anti-glare film exhibits excellent adhesion to the substrate 3. If the total content of silica precursor (A) and particles (C) is below the upper limit of the above range, cracking and peeling of the anti-glare film 5 are suppressed.

[0245] When the coating composition contains a silica precursor (A), the content of silica precursor (A) (converted to SiO2) in the coating composition is preferably 35 to 95% by mass of the solid components (100% by mass) of the coating composition (wherein, silica precursor (A) is converted to SiO2), and more preferably 50 to 95% by mass.

[0246] If the content of silica precursor (A) is above the lower limit of the above range, sufficient adhesion strength between the anti-glare film and the substrate 3 can be obtained. If the content of silica precursor (A) is below the upper limit of the above range, cracks and peeling of the anti-glare film 5 can be sufficiently suppressed even with a thick unevenness.

[0247] When the coating composition contains a silica precursor (A) and the silica precursor (A) contains either or both of a silane compound (A1) and its hydrolysate, the ratio of the silane compound (A1) and its hydrolysate in the silica precursor (A) relative to the SiO2 equivalent solids content (100% by mass) of the silica precursor (A) is preferably 5 to 100% by mass. If the ratio of the silane compound (A1) and its hydrolysate is above the lower limit of the above range, cracking and peeling of the anti-glare film 5 can be sufficiently suppressed even with a high degree of unevenness.

[0248] When the coating composition contains a silica precursor (A) and the silica precursor (A) contains either or both of a tetraalkoxysilane and its hydrolysate, the proportion of either or both of the tetraalkoxysilane and its hydrolysate in the silica precursor (A) relative to the SiO2 equivalent solids content (100% by mass) of the silica precursor (A) is preferably 60 to 100% by mass. If the proportion of either or both of the tetraalkoxysilane and its hydrolysate is above the lower limit of the above range, the anti-glare film 5 exhibits superior wear resistance.

[0249] When the silica precursor (A) comprises any or both of a silane compound (A1) and its hydrolysis condensate, and any or both of a tetraalkoxysilane and its hydrolysis condensate, the proportion of the silane compound (A1) and its hydrolysis condensate to the SiO2 equivalent solids content (100% by mass) of the silica precursor (A) is preferably more than 0% by mass and less than 50% by mass (more preferably more than 0% by mass and less than 30% by mass), and the proportion of the tetraalkoxysilane and its hydrolysis condensate is more than 50% by mass and less than 100% by mass (more preferably more than 70% by mass and less than 100% by mass).

[0250] The content of liquid medium (B) in the coating composition is the amount corresponding to the concentration of solid components in the coating composition.

[0251] The concentration of solid components in the coating composition is preferably 1 to 8% by mass, more preferably 2 to 6% by mass, in the total amount (100% by mass) of the coating composition.

[0252] If the concentration of the solid component is above the lower limit of the above range, the volume of the coating composition can be reduced. If the concentration of the solid component is below the upper limit of the above range, the uniformity of the unevenness of the anti-glare film is improved.

[0253] The solid content concentration of the coating composition is the total content of all components in the coating composition except for the liquid medium (B). The content of the silica precursor (A) is converted from SiO2.

[0254] The content of the liquid medium (B1) with a boiling point below 150°C in the coating composition is 86% by mass or more relative to the total amount of liquid medium (B). By including the liquid medium (B1) at a proportion of 86% by mass or more, when the coating composition is applied to a substrate and calcined using an electrostatic coating apparatus equipped with an electrostatic coating gun with a rotating atomizing head, an anti-glare film with better performance is formed. If the proportion of liquid medium (B1) is less than 86% by mass, since it is smoothed before the solvent evaporates and dries, an uneven structure cannot be formed, and the film after calcination may not become an anti-glare film.

[0255] The content of liquid medium (B1) relative to the total amount of liquid medium (B) is preferably 90% by mass or more. The content of liquid medium (B1) may also be 100% by mass relative to the total amount of liquid medium (B).

[0256] When the coating composition contains particles (C), the content of particles (C) in the solid components (100% by mass) of the coating composition (wherein, the silica precursor (A) is converted to SiO2) is preferably 3 to 40% by mass, more preferably 5 to 30% by mass.

[0257] If the content of particle (C) is above the lower limit of the above range, the haze of the substrate with the anti-glare film becomes sufficiently high, and the 60° specular gloss of the surface of the anti-glare film becomes sufficiently low, thus fully realizing the anti-glare effect. If the content of particle (C) is below the upper limit of the above range, sufficient wear resistance can be obtained.

[0258] When the coating composition contains particles (C) and the particles (C) include flake-like particles (C1), the content of flake-like particles (C1) in the total amount of particles (C) (100% by mass) is preferably 20% by mass or more, more preferably 30% by mass or more. There is no particular upper limit, and it can be 100% by mass.

[0259] If the proportion of flaky particles (C1) is above the lower limit mentioned above, the anti-glare effect is even better. In addition, even with a thicker texture, cracks and peeling of the anti-glare film can be effectively suppressed.

[0260] (Viscosity of the coating composition)

[0261] The viscosity (hereinafter also referred to as "liquid viscosity") of the coating composition at the coating temperature is preferably 0.003 Pa·s or less (3 mPa·s or less), and particularly preferably 0.001 to 0.003 Pa·s. If the liquid viscosity is below the above upper limit, the droplets formed when the coating composition is sprayed become finer, making it easier to form an anti-glare film with the desired surface shape. If the liquid viscosity is above the above lower limit, the surface unevenness of the anti-glare film becomes more uniform.

[0262] The viscosity of the coating composition is the value measured using a type B viscometer.

[0263] (Preparation method of coating composition)

[0264] The coating composition can be prepared, for example, by preparing a solution of silica precursor (A) dissolved in a liquid medium (B), and mixing additional liquid medium (B), particle (C) dispersion, etc., as needed.

[0265] When the particles (C) contain flake particles (C1) and the silica precursor (A) contains a hydrolysis condensate of tetraalkoxysilane, from the viewpoint of being able to manufacture an anti-glare film with the desired performance with good reproducibility at a high level, it is preferable to mix a solution of tetraalkoxysilane or a solution of a mixture of tetraalkoxysilane and its hydrolysis condensate with a dispersion of flake particles (C1), and then hydrolyze and condense the tetraalkoxysilane in the presence of the flake particles (C1).

[0266] [Conductive film formation process]

[0267] In the conductive film formation process, a conductive film is formed on the surface of a masking material. By using the masking material with the conductive film formed thereon for masking, the anti-glare coating liquid is uniformly adhered near the masking material as well. It is believed that this is because the electrostatic repulsion at the masking end face caused by the applied voltage is mitigated by the conductive film, thus uniformly forming the anti-glare film.

[0268] (Conductive film)

[0269] The conductive film is preferably a film made of a conductive material, and more preferably a metal film. If an insulating layer is formed on the surface of the conductive film, it is easy to become charged; therefore, a conductive film whose surface does not form oxides or the like is preferred. Since the oxidation tendency is represented by the standard electrode potential, a metal with a positive standard electrode potential is preferred, more preferably a metal with a standard electrode potential of 0.78 eV or higher, and particularly preferably a metal with a standard electrode potential of 0.79 eV or higher. Specifically, the conductive film is preferably a noble metal film, and Pt, Au, and Ag are particularly preferred as noble metals.

[0270] If the standard electrode potential is within the above-mentioned range, a chemically stable conductive film can be easily formed. It should be noted that the standard electrode potential of the conductive film is the same as the standard electrode potential of the material constituting the conductive film. That is, the standard electrode potential of the conductive film is preferably positive, more preferably 0.78 eV or higher, and particularly preferably 0.79 eV or higher.

[0271] Furthermore, the lower the surface resistivity of the conductive film, the more uniform the anti-glare film becomes at the interface of the masking material, regardless of the substrate, which is therefore preferable. If it is a Pt film, a surface resistivity of 10 is preferred. 6 Ω / □ or less, more preferably 10 3 Below Ω / □.

[0272] (Methods for forming conductive films)

[0273] Conductive films can be formed using dry coating methods such as sputtering and evaporation. From the viewpoint of being able to form large-area films, sputtering is preferred.

[0274] The sputtering time is preferably 1 to 10 minutes, which can be adjusted appropriately according to the material, target film thickness and surface resistivity.

[0275] [Concealing process]

[0276] like Figure 6 As shown in (a) and (b), in the masking process, at least a portion of a main surface of the substrate 3 is covered with a masking material 7 having a conductive film 9 formed thereon. At this time, of the two main surfaces of the masking material 7, the main surface 7A side without a conductive film is laminated to the substrate side.

[0277] (Covering material)

[0278] As a masking material, polyethylene films, acrylic films, etc., can be used. Alternatively, acrylic adhesives can be applied as needed. The shape of the non-anti-glare section in the top view is not particularly limited; circles, ovals, triangles, rectangles, squares, trapezoids, etc., can be appropriately selected. Furthermore, the size of the non-anti-glare section can be appropriately designed according to the application of the substrate with the anti-glare film. To achieve the desired shape and size of the non-anti-glare section, the masking material attached to it only needs to be adjusted in shape and size appropriately.

[0279] Furthermore, the thickness of the masking material is preferably 500 μm or less, more preferably 300 μm or less, and particularly preferably 100 μm or less. If the thickness of the masking material is within the above range, it is less susceptible to electrostatic repulsion caused by the application of voltage to the side of the masking material.

[0280] [Coating process]

[0281] In the coating process, the coating composition is charged and sprayed onto the substrate by using an electrostatic coating device to form a coating film.

[0282] The coating of the above-mentioned coating composition onto a substrate is performed by using an electrostatic coating apparatus to charge the coating composition and spray it. This forms a coating film of the coating composition on the substrate.

[0283] (Electrostatic coating equipment)

[0284] As an electrostatic coating apparatus, for example, an electrostatic coating apparatus with an electrostatic coating gun equipped with a rotating atomizing head can be used. The coating composition is atomized into droplets in the rotating atomizing head and dispersed radially. The droplets carry a negative charge and are attracted to the grounded substrate by electrostatic attraction. Therefore, it adheres to the surface of the substrate efficiently.

[0285] During electrostatic coating, the surface temperature of the substrate is preferably below 60°C, preferably between 15 and 50°C, and more preferably between 20 and 40°C. If the surface temperature of the substrate is above the lower limit of the above range, the liquid medium (B) of the coating composition evaporates rapidly, thus easily forming sufficient unevenness. If the surface temperature of the substrate is below the upper limit of the above range, the adhesion between the substrate and the anti-glare film becomes good. The preferred ranges for the temperature of the coating composition sprayed by the electrostatic coating gun (coating temperature) and the temperature inside the coating chamber are also the same as described above.

[0286] The substrate conveying speed is preferably 0.6 to 20.0 m / min, more preferably 1.5 to 15.0 m / min. If the substrate conveying speed is 0.6 m / min or more, productivity is improved. If the substrate conveying speed is 20.0 m / min or less, the film thickness of the coating composition applied to the substrate is easily controlled.

[0287] The number of times the substrate 3 is fed, i.e., the number of times the substrate passes under the electrostatic coating gun to apply the coating composition, can be appropriately set according to the desired haze and gloss. From the perspective of anti-glare, it is preferable to do it once or more, more preferably twice or more. From the perspective of productivity, it is preferable to do it 10 times or less, more preferably 8 times or less.

[0288] The diameter of the outer periphery of the rotating atomizing head of the electrostatic coating gun (the maximum diameter of the diffusion surface, hereinafter also referred to as the "cup diameter") Dc is preferably 50 mm or more, preferably 55 to 90 mm, and particularly preferably 60 to 80 mm. If the cup diameter is above the lower limit mentioned above, the centrifugal force during the rotation of the rotating atomizing head is large, and the droplets of the material composition dispersed from the rotating atomizing head become finer, making it easier to form an anti-glare film with the desired surface shape. If the cup diameter is below the upper limit of the above range, the cup can rotate stably.

[0289] The distance from the tip of the nozzle of the electrostatic coating gun (i.e., the tip of the rotating atomizing head in the spray direction of the coating composition) to the substrate (hereinafter also referred to as the nozzle height) is appropriately adjusted according to the width of the substrate 3, the film thickness of the coating composition applied to the substrate 3, etc. It is usually 150 to 450 mm.

[0290] Shortening the distance to the substrate 3 improves coating efficiency, but getting too close increases the likelihood of discharge and poses safety risks. On the other hand, increasing the distance to the substrate expands the coating area, but excessively increasing this distance leads to a decrease in coating efficiency.

[0291] The voltage applied to the electrostatic coating gun can be appropriately adjusted according to the coating composition and the amount of coating applied to the substrate, typically ranging from -30kV to -90kV. There is a trend that the higher the absolute value of the voltage, the higher the coating efficiency. It should be noted that, although it also depends on the liquid properties, coating environment, and coating conditions, the coating efficiency reaches saturation when the applied voltage reaches a certain level.

[0292] The supply rate of the coating composition to the electrostatic coating gun (hereinafter also referred to as the coating liquid rate) can be appropriately adjusted according to the coating amount of the coating composition applied to the substrate. Preferably, it is less than 70 mL / min, more preferably 10 to 50 mL / min.

[0293] If the amount of coating liquid is below the upper limit mentioned above, the droplets of the coating composition dispersed from the rotating atomizing head become finer, making it easier to form an anti-glare film with the desired surface shape. If the amount of coating liquid is above the lower limit mentioned above, the distribution of in-plane haze rate becomes smaller.

[0294] The air pressure supplied to the electrostatic coating gun can be appropriately adjusted according to the coating amount of the paint composition applied to the substrate, and is typically 0.01 MPa to 0.5 MPa. The coating pattern of the paint composition can be controlled by the air pressure supplied to the electrostatic coating gun.

[0295] The coating pattern of a coating composition refers to the pattern formed on a substrate by droplets of the coating composition sprayed from an electrostatic coating gun.

[0296] When the air pressure supplied to the air turbine motor inside the electrostatic coating gun is increased, the rotational speed of the rotating shaft increases, and the rotational speed of the rotating atomizing head increases, thus showing a trend of smaller droplet size and larger coating pattern from the rotating atomizing head.

[0297] Increasing the air pressure supplied to the air supply path inside the electrostatic coating gun and increasing the air pressure discharged from the outlet (shaping air) shows a trend that the diffusion of droplets flying from the rotating atomizing head is suppressed and the coating pattern becomes smaller.

[0298] The air pressure supplied to the air turbine motor can be set according to the rotational speed of the rotating atomizing head (hereinafter also referred to as the cup speed). The higher the air pressure, the faster the cup speed.

[0299] The cup rotation speed is preferably above 30,000 rpm, more preferably 30,000 to 80,000 rpm, and particularly preferably 32,000 to 80,000 rpm.

[0300] If the cup rotation speed is above the lower limit of the above range, the droplets of the coating composition dispersed from the rotating atomizing head become finer, making it easier to form an anti-glare film with the desired surface shape. If the cup rotation speed is below the upper limit of the above range, the coating efficiency is excellent.

[0301] The cup rotation speed can be measured using a measuring instrument attached to the electrostatic coating device (illustration omitted).

[0302] The air pressure supplied to the air supply path is preferably in the range of 0.01 to 0.3 MPa, which is also referred to as the forming pressure. More preferably, the forming pressure is 0.01 to 0.25 MPa, and particularly preferably 0.01 to 0.2 MPa. If the forming pressure is above or below the lower limit of the above range, the coating efficiency is significantly improved due to the enhanced droplet scattering prevention effect. If the forming pressure is below or below the upper limit of the above range, the coating width can be ensured.

[0303] [Mask Removal Process]

[0304] In the masking removal process, the masking material is removed from the substrate. For example... Figure 6 As shown in (c) and (d), the coating 51 is removed along with the masking material 7. Therefore, the portion of the substrate 3 not covered by the masking material forms an anti-glare film 5 and becomes an anti-glare part 50, while the portion of the substrate 3 covered by the masking material does not form an anti-glare film 5 and becomes a non-anti-glare part 30.

[0305] As a removal method, a portion of the end face can be peeled off using a clamp, or a clamp with adhesive attached can be pressed against the periphery of the masking material to peel it off. Alternatively, it can be burned off during the calcination process described later.

[0306] It should be noted that the masking removal can also be carried out after the calcination process described later.

[0307] [Calcination process]

[0308] In the calcination process, the coating film formed on the substrate by the coating composition in the coating process is calcined to produce an anti-glare film.

[0309] Calcination can be carried out simultaneously with coating by heating the substrate when the coating composition is applied to the substrate, or by heating the coating film after the coating composition has been applied to the substrate.

[0310] The calcination temperature is preferably above 30°C, more preferably 100-750°C when the substrate is glass, and even more preferably 150-550°C.

[0311] In the manufacturing method described above, when forming the anti-glare film on the substrate, the anti-glare film can be formed approximately uniformly up to the vicinity of the area covered by the masking material. Therefore, it is possible to manufacture a substrate with an anti-glare film, having an anti-glare portion and a non-anti-glare portion, wherein the anti-glare film is formed approximately uniformly on the substrate near the boundary between the anti-glare portion and the non-anti-glare portion, and the boundary between the anti-glare portion and the non-anti-glare portion is clear.

[0312] Example

[0313] The present invention will now be described in detail with reference to embodiments. However, the present invention is not limited to the following description.

[0314] In Examples 1 to 8 described below, Examples 1 to 3 and Examples 6 to 8 are examples, and Examples 4 and 5 are comparative examples.

[0315] <Coating Preparation>

[0316] (Preparation of flake-shaped silica particle dispersion (a))

[0317] [Formation of silica powder]

[0318] A sodium silicate aqueous solution (SiO2 / Na2O = 3.0 (molar ratio), SiO2 concentration: 21.0 wt%) and a sulfuric acid aqueous solution (sulfuric acid concentration: 20.0 wt%) were instantaneously and uniformly mixed by introducing them into a container with an outlet through separate inlets to generate silica sol. The flow rate ratio of the two solutions was adjusted so that the pH of the silica sol released into the air from the outlet was 7.5–8.0. The silica sol was continuously released into the air from the outlet. The silica sol formed spherical droplets in the air, drew a parabola, and gelled in the air during a period of about 1 second. The gelled material was then allowed to fall into a curing tank filled with water for curing. After curing, the pH was adjusted to 6, and the mixture was further washed thoroughly with water to obtain silica hydrogel. The obtained silica hydrogel consisted of spherical particles with an average particle size of 6 mm. The mass ratio of water to SiO2 in the silica hydrogel was 4.55.

[0319] The silica hydrogel was coarsely pulverized to an average particle size of 2.5 mm using a two-roll crusher. Capacity: 17 m³ / s. 37249 kg of silica hydrogel (SiO2 concentration: 18 wt%) and 1500 kg of sodium silicate aqueous solution (SiO2 concentration: 29.00 wt%, Na2O concentration: 9.42 wt%, SiO2 / Na2O = 3.18 wt%) were loaded into a high-pressure autoclave (with anchor-type stirring blades) with a total SiO2 / Na2O molar ratio of 12.0. Water (1560 kg) was added, and high-pressure steam (4682 kg) at a saturated pressure of 1.67 MPa was added while stirring at 10 rpm. The mixture was heated to 185 °C and subjected to hydrothermal treatment for 5 hours to obtain a silica dispersion. The total SiO2 concentration in the system was 12.5 wt%.

[0320] The obtained silica dispersion was filtered and washed to obtain silica powder, which was then observed using TEM. Silica aggregates were confirmed to be present in the silica powder. The average particle size of the silica powder, measured using a laser diffraction / scattering particle size distribution measuring device (Horiba Manufacturing Co., Ltd., LA-950, hereinafter the same), was 8.33 μm.

[0321] [Acid Treatment]

[0322] While stirring a silica dispersion containing silica powder (solid concentration measured using an infrared moisture meter: 13.3% by mass, pH: 11.4) (10100 g), an aqueous sulfuric acid solution (sulfuric acid concentration: 20% by mass) (1083 g) was added. The pH after addition was 1.5. Stirring was continued directly at room temperature for 18 hours for further processing.

[0323] The acid-treated silica dispersion was filtered, and each 1 g of SiO2 was washed with 50 mL of water. The washed silica filter cake was collected, and water was added to prepare a slurry-like silica dispersion. The solid content of the silica dispersion, measured using an infrared moisture analyzer, was 14.7% by mass, and the pH was 4.8.

[0324] [Aluminate treatment]

[0325] The acid-treated silica dispersion (7000g) was placed in a 10L flask, and sodium aluminate aqueous solution (concentration: 2.02% by mass) (197g) (Al2O3 / SiO2 = 0.00087 molar ratio) was added in small increments while stirring with a top stirrer. The pH after addition was 7.2. After addition, stirring was continued at room temperature for 1 hour. Then, the temperature was raised, and the mixture was treated under reflux for 4 hours.

[0326] [Alkali Treatment]

[0327] Aluminate-treated silica dispersion (775 g) was mixed with potassium hydroxide (43.5 g) (1 mmol / g silica) and water (1381 g) while stirring. The pH after addition was 9.9. The mixture was then stirred continuously at room temperature for 24 hours for further treatment. The average particle size of the alkali-treated silica powder was 7.98 μm.

[0328] [Wet crushing]

[0329] The alkali-treated silica dispersion was processed using an ultra-high pressure wet micronization device (manufactured by Yoshida Machinery Co., Ltd., Nanozizer (registered trademark) NM2-2000AR, 120μm aperture impactor) at a spray pressure of 130-140MPa for 30 passes to break down and disperse the silica powder. The pH of the broken-down silica dispersion was 9.3, and the average particle size, measured using a laser diffraction / scattering particle size distribution analyzer, was 0.182μm.

[0330] [Cation exchange]

[0331] A cation exchange resin (161 mL) was added to the fragmented silica dispersion (1550 g), and the mixture was treated at room temperature for 17 hours with stirring using a top-mounted stirrer. The cation exchange resin was then separated. The pH of the cation-exchanged silica dispersion was 3.7.

[0332] [Concentration Adjustment]

[0333] The cation-exchanged silica dispersion was treated with an ultrafiltration membrane (manufactured by DAICEN MEMBRANE SYSTEMS, MOLSEP (registered trademark), molecular weight cutoff: 150,000) to adjust the concentration.

[0334] Silica particles were taken from the obtained silica dispersion (a) and observed using TEM. The results confirmed that the silica particles were only flake-shaped silica particles that did not actually contain amorphous silica particles.

[0335] The average particle size of the flake-shaped silica particles in the dispersion (a) is the same as that after wet fragmentation, which is 0.182 μm. The average aspect ratio is 188.

[0336] The solid content concentration of the flake silica particle dispersion (a), as measured by an infrared moisture analyzer, was 5.0% by mass.

[0337] (Preparation of base liquid (b))

[0338] While stirring, 35.90 g of modified ethanol (manufactured by Nippon Alcohol Sales Co., Ltd., Solmix (registered trademark) AP-11, a mixed solvent with ethanol as the main agent, boiling point 78°C. The same applies below) was added, along with 4.39 g of Silicate 40 (manufactured by Tama Chemical Industry Co., Ltd., a mixture of tetraethoxysilane and its hydrolysate condensate, solid content concentration (SiO2 conversion): 40% by mass, solvent: ethanol (10% or less). The mixture was stirred for 30 minutes. Then, a mixture of ion-exchanged water (3.71 g) and an aqueous nitric acid solution (nitric acid concentration: 61% by mass) (0.06 g) was added, and the mixture was stirred for 60 minutes to prepare a base solution (b) with a solid content concentration (SiO2 conversion) of 4.0% by mass. It should be noted that the SiO2 conversion solid content concentration is the solid content concentration when all Si in Silicate 40 is converted to SiO2.

[0339] (Preparation of silane compound solution (c))

[0340] While stirring modified ethanol (3.85 g), a mixture of ion-exchanged water (0.37 g) and nitric acid aqueous solution (nitric acid concentration: 61 wt%) (0.01 g) was added, and the mixture was stirred for 5 minutes. Next, 1,6-bis(trimethoxysilyl)hexane (manufactured by Shin-Etsu Chemical Industry Co., Ltd., KBM-3066, solid content concentration (SiO2 conversion): 37 wt%) (0.54 g) was added, and the mixture was stirred in a water bath at 60°C for 15 minutes to prepare a silane compound solution (c) with a solid content concentration (SiO2 conversion) of 4.3 wt%.

[0341] (Preparation of coating solution (d))

[0342] While stirring the base solution (b) (46.15 g), add the silane compound solution (c) (4.77 g) and stir for 60 minutes. Add modified ethanol (154.19 g) and stir for 30 minutes at room temperature to obtain a coating solution (d) with a solid content concentration (SiO2 conversion) of 1.0% by mass.

[0343] [Example 1]

[0344] <Cleaning of substrate>

[0345] As the substrate, a soda-lime glass substrate (manufactured by AGC Corporation, FL1.1, size: 100mm × 100mm, thickness: 1.1mm) was prepared. The surface of the glass was cleaned with a sodium bicarbonate aqueous solution, rinsed with deionized water, and dried.

[0346] <Fabrication of Masking Materials with Conductive Films>

[0347] Masking film A (KTF-50SU, a single-sided adsorption type film manufactured by Tokyo Film Service Co., Ltd.) was used as the masking material. The masking material was cut into 12mm Φ circles for use. A metal layer (platinum layer) was deposited on the cut masking material as a conductive film. Specifically, a laboratory sputtering apparatus (Sanyu Electronics Co., Ltd. SC-701) equipped with a Pt target (manufactured by Tanaka Precious Metals Industry Co., Ltd., 99.99% purity) was used to perform sputtering treatment at a current of 5mA for 1 minute to deposit the platinum layer and create the masking material.

[0348] <Fabrication of Substrates with Masking Material>

[0349] The masking material with the conductive film is held with tweezers and attached to the substrate in a way that minimizes the formation of air bubbles, thus creating a substrate with the masking material.

[0350] <Electrostatic Coating Equipment>

[0351] As the electrostatic coating apparatus, a liquid electrostatic coating machine (manufactured by Asahi Sunac Co., Ltd.) is prepared. As the electrostatic coating gun, a rotary atomizing automatic electrostatic gun (manufactured by Asahi Sunac Co., Ltd., SUNBELL, ESA120) is prepared. cup).

[0352] To facilitate grounding of the substrate, a metal mesh tray is prepared as a conductive substrate.

[0353] <Production using anti-glare film applied by electrostatic coating>

[0354] Adjust the temperature inside the coating chamber of the electrostatic coating device to 25±1℃ and the humidity to 50%±10%.

[0355] A preheated substrate with masking material, cleaned and placed between a conductive substrate and a preheated (30℃±3℃) substrate, is placed on a chain conveyor of an electrostatic coating apparatus. While the substrate is conveyed at a constant speed using the chain conveyor, an electrostatic coating method is employed to apply coating liquid (d) to the top surface of the substrate with masking material (the side opposite to the surface in contact with molten tin during float glass manufacturing), forming a coating film on the substrate with masking material. The electrostatic coating method operates under the following conditions: applied voltage -60kV, coating liquid volume 30mL, distance from nozzle tip to glass plate 250mm, forming pressure 0.04MPa, cup rotation speed 30krpm, substrate conveying speed 2m / min, and substrate conveying times 2 times.

[0356] The masking material is removed by peeling it off from the substrate with the masking material by pressing a rod-shaped clamp with an adhesive sheet wrapped around its front end. Then, it is calcined in the atmosphere at 300°C for 30 minutes to form an anti-glare film, resulting in a substrate with an anti-glare part and a non-anti-glare part, and a substrate with an anti-glare film.

[0357] The following evaluation was performed on the substrate before the removal of the masking material and the resulting substrate with the anti-glare film. The results are shown in Table 1.

[0358] <Determination of the unevenness of anti-glare film>

[0359] The roughness height of the anti-glare film's end was measured using a stylus-type profilometry system (BRUKER, Dektak (registered trademark) XT) under the following conditions: measurement length 1000 μm, load 10 mg, measurement time 10 sec, and probe tip diameter 12.5 μm. The obtained roughness data were used to flatten the baseline. The measurement distance x is the distance (μm) from the measurement start position in the measurement direction, and the cumulative value y is the cumulative value (μm) of the anti-glare film's roughness height (0.333 μm per unit). A graph of the above measurement results was plotted in an x-y orthogonal coordinate system.

[0360] The point where the cumulative value y > 5 and the measurement distance x is the smallest is set as the end of the anti-glare film X1(x1, y1), and the measurement distance x is represented by... a =The cumulative value y at (x1+100) a Let the point be A(x) a y a ), which will represent the measured distance x b =(x a The cumulative value y at +200) b Let the point be B(x) b y b Draw a regression line between A and B. Set the x-intercept of the above regression line as X2(x2, 0), and calculate the value P(μm) as x1-x2=P···(Equation 1).

[0361] For each sample, the concavity and convexity height were measured three times and the value P was calculated to obtain the maximum, minimum and average values ​​of P.

[0362] (Observation of end-face characteristics before removal of masking material)

[0363] The surface shape near the masking material after electrostatic coating on a substrate with masking material was measured using a VK-X100 laser microscope manufactured by KEYENCE Co., Ltd. It should be noted that a "×10" objective lens was used, and the measurement was performed at 100x magnification.

[0364] (Surface resistivity measurement)

[0365] The surface resistivity of the masking material with conductive film was measured using a strip of conductive film with the same formulation as the masking material described above, but with a size of 5 mm × 50 mm, using a surface resistivity meter (Mitsubishi Chemical Corporation, Loresta T600) with a four-probe probe.

[0366] (Standard electrode potential measurement)

[0367] The standard electrode potentials of the conductive films in masking materials with conductive films are taken from the 6th edition of the Electrochemistry Handbook (published by Maruzen).

[0368] <Visually determined haze unevenness at the end face of the anti-glare film>

[0369] Determine whether uneven haze can be seen on the end face (edge) of the anti-glare film.

[0370] ◎: Completely invisible

[0371] 〇: Almost impossible to see

[0372] ×: Uneven haze can be seen.

[0373] [Example 2]

[0374] In the fabrication of the masking material, the sputtering process time was changed to 2 minutes. Otherwise, a substrate with an anti-glare film was fabricated in the same manner as in Example 1, and the above evaluation was performed. The results are shown in Table 1.

[0375] [Example 3]

[0376] In the fabrication of the masking material, the sputtering process time was changed to 3 minutes. Otherwise, a substrate with an anti-glare film was fabricated in the same manner as in Example 1, and the above evaluation was performed. The results are shown in Table 1.

[0377] [Example 4]

[0378] In the fabrication of the masking material, sputtering was not performed, and no conductive film was applied. Otherwise, a substrate with an anti-glare film was fabricated in the same manner as in Example 1, and the above evaluation was performed. The results are shown in Table 1.

[0379] [Example 5]

[0380] Using masking material B (HG1, a single-sided adsorption type film manufactured by Fujicopian Co., Ltd.) as the masking material, a substrate with an anti-glare film was prepared in the same manner as in Example 4, and the above evaluation was performed. The results are shown in Table 1.

[0381] [Example 6]

[0382] The target used in the sputtering process was changed to an Au target (manufactured by Tanaka Precious Metals Industry Co., Ltd., 99.99% purity). A gold (Au) layer was formed on the masking material as a conductive film. Otherwise, a substrate with an anti-glare film was fabricated in the same manner as in Example 3. The substrate with the anti-glare film before the masking material was removed, or the substrate with the obtained anti-glare film, was evaluated as described above. The results are shown in Table 1.

[0383] [Example 7]

[0384] The target used in the sputtering process was changed to an Ag target (manufactured by Tanaka Precious Metals Industry Co., Ltd., 99.99% purity). A silver (Ag) layer was formed on the masking material as a conductive film. Otherwise, a substrate with an anti-glare film was fabricated in the same manner as in Example 3. The substrate with the anti-glare film before the masking material was removed, or the substrate with the obtained anti-glare film, was evaluated as described above. The results are shown in Table 1.

[0385] [Example 8]

[0386] The substrate was transported once during electrostatic coating, and otherwise, a substrate with an anti-glare film was fabricated in the same manner as in Example 3. The substrate with the anti-glare film before the masking material was removed, or the substrate with the anti-glare film obtained, was evaluated as described above. The results are shown in Table 1.

[0387] Furthermore, regarding the unevenness height of the anti-glare film on the substrate with the anti-glare film in Example 3 above, a curve diagram showing the relationship between the measured distance x and the unevenness height z will be plotted in an x-y orthogonal coordinate system. Figure 7 The curve obtained by plotting the relationship between the measured distance x and the cumulative value y of the concavity and convexity in an x-y orthogonal coordinate system will be plotted in the graph. Figure 8 It should be explained that... Figure 8 The dashed line in the middle represents the regression line.

[0388] Then, for the anti-glare film height of the substrate with anti-glare film in Example 5, a curve graph showing the relationship between the measured distance x and the anti-glare height z will be plotted in an x-y orthogonal coordinate system. Figure 9 The curve obtained by plotting the relationship between the measured distance x and the cumulative value y of the concavity and convexity in an x-y orthogonal coordinate system will be plotted in the graph. Figure 10 It should be explained that... Figure 10 The dashed line in the middle represents the regression line.

[0389] Furthermore, for the substrates in Examples 3 to 6 above, microscopic photographs obtained by observing the surface shape near the masking material after electrostatic coating on the substrate with masking material from the top surface direction are shown respectively. Figures 11-14 .

[0390] [Table 1]

[0391]

[0392] Based on the above results, it is shown that the substrate with anti-glare film has an average value of P of -20μm or more, and the anti-glare film is uniformly formed and the boundary between the anti-glare part and the non-anti-glare part is clear.

[0393] Various embodiments have been described above with reference to the accompanying drawings, but the present invention is not limited to the examples described above. Those skilled in the art will readily conceive of various modifications or alterations within the scope of the patent claims, and these are to be understood as falling within the technical scope of the present invention. Furthermore, the constituent elements of the above embodiments can be combined arbitrarily without departing from the spirit of the invention.

[0394] It should be noted that this application is based on Japanese patent application filed on June 3, 2020 (Japanese Patent Application No. 2020-097127), the contents of which are incorporated herein by reference.

[0395] Industrial availability

[0396] One embodiment of the present invention provides a substrate with an anti-glare film in which the anti-glare film is formed substantially uniformly on the substrate near the boundary between the anti-glare portion and the non-anti-glare portion, and the boundary between the anti-glare portion and the non-anti-glare portion is clear. This is useful in various devices such as smartphones equipped with cameras, where it is required that an anti-glare film not be formed in the portion of the substrate that serves as a cover plate, corresponding to the camera's field of view, to prevent a decrease in camera resolution, etc.

[0397] Symbol Explanation

[0398] 1. Substrate with anti-glare film

[0399] 3. Substrate

[0400] 3A First Main Face

[0401] 5. Anti-glare film

[0402] 30 Non-anti-glare section

[0403] 50 Anti-glare section

[0404] 51 Coating

[0405] 40 Connecting Area

[0406] 7. Covering materials

[0407] 7A Main Face

[0408] 9. Conductive film

Claims

1. A substrate with an anti-glare film, comprising a substrate and an anti-glare film formed on at least a portion of a main surface of the substrate, the substrate with the anti-glare film having: An anti-glare portion of the anti-glare film is formed on at least one main surface of the substrate; and In the non-anti-glare portion where the anti-glare film is not formed on at least one main surface of the substrate, Based on the measurement results of the unevenness height of the anti-glare film in the area adjacent to the anti-glare part and the non-anti-glare part using the following measurement method, the average value P calculated using the following formula is 20 μm or more. Method for measuring the height of concavity and convexity: Set the measurement start position to the non-anti-glare part. The measurement direction is set perpendicular to the boundary line between the anti-glare section and the non-anti-glare section, and from the non-anti-glare section toward the anti-glare section. The unevenness height of the anti-glare film was measured at intervals of 0.333 μm from the starting position on the non-anti-glare part to the anti-glare part. The method for calculating the value P: Let the measurement distance from the starting position of the measurement to the measurement direction be x (μm), and let the cumulative value of the unevenness height of the anti-glare film be y (μm), thus creating an x-y coordinate plane. The point where the cumulative value y > 5 and the measurement distance x is the smallest is set as the end of the anti-glare film X1(x1, y1), and the measurement distance x is represented by... a =The cumulative value y at (x1+100) a Let the point be A(x) a y a ), which will represent the measured distance x b =(x a The cumulative value y at +200) b Let the point be B(x) b y b ), Draw a regression line between A and B. Let the x-intercept of the regression line be X2(x2, 0), and calculate the value P(μm) using the following (Equation 1). x1-x2=P···(Equation 1).

2. The substrate with anti-glare film according to claim 1, wherein, The anti-glare film contains silicon dioxide.

3. The substrate with anti-glare film according to claim 1 or 2, wherein, The substrate is a glass plate.

4. The substrate with an anti-glare film according to any one of claims 1 to 3, wherein, The substrate has a curved surface.

5. A method for manufacturing a substrate with an anti-glare film, comprising the method for manufacturing the substrate with an anti-glare film as described in claim 1. The manufacturing method comprises the following steps: Prepare a coating composition comprising at least one of a silica precursor (A) and particles (C), and a liquid medium (B), wherein the liquid medium (B) comprises a liquid medium (B1) having a boiling point below 150°C in an amount of 86% by mass or more relative to the total amount of the liquid medium (B). A conductive film is formed on the surface of the masking material; A portion of at least one main surface of the substrate is covered with a masking material on which the conductive film is formed; The coating composition is charged and sprayed onto the substrate to form a coating film by using an electrostatic coating device; Remove the masking material from the substrate; and An anti-glare film is formed by calcining the coating.

6. The manufacturing method according to claim 5, wherein, The standard electrode potential of the conductive film is above 0.78 eV.

7. The manufacturing method according to claim 5 or 6, wherein, The conductive film is a metal film.

8. The manufacturing method according to any one of claims 5 to 7, wherein, The conductive film is a noble metal film.

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