WO2018151095A1 - Article having antiglare surface - Google Patents

Abstract

A glass article (10) used in a region where pen input operation is performed is provided with a glass substrate (11) that is a substrate and an antiglare film (12) provided on the glass substrate (11). The number of projections per mm² of 1 µm or greater in diameter and 1 µm or greater in height that exist on the surface of the antiglare film (12), i.e., on an antiglare surface, is 50 or greater.

Description

Articles having an antiglare surface

The present invention relates to an article used for a pen input device and having an antiglare surface.

Conventionally, from the viewpoint of improving the visibility of a display device, it has been proposed to provide an antireflection layer or an antiglare layer on the display surface of the display device. For example, in Patent Document 1, an antireflection film having a low refractive index layer is provided on a base material, and the main surface of the low refractive index layer is antiglare-treated to provide not only an antireflection function but also an antiglare function. The formation of a protective film is described.

Further, Patent Document 2 and Patent Document 3 disclose that an antiglare-treated glass article is used as a cover glass for a pen input device.

Japanese Patent Laid-Open No. 10-221506 JP 2004-240548 A International Publication WO2015 / 072297

By the way, it is preferable that a member that receives a pen input operation, such as a cover glass of a pen input device, obtains a writing feeling close to an actual writing when the pen input operation is performed, that is, has good writing quality.

The present invention has been made in view of such circumstances, and an object thereof is to provide an article having an antiglare surface, which has excellent writing quality when a pen input operation is performed.

An article for achieving the above object is an article used in a site where a pen input operation is performed, and includes a base material and an antiglare surface provided on at least one surface of the base material. The number per 1 mm ^{2 of} protrusions having a diameter of 1 μm or more and a height of 1 μm or more present on the surface is 50 or more.

In the above article, the antiglare surface is preferably composed of an antiglare film containing at least one selected from SiO ₂ , Al ₂ O ₃ , ZrO ₂ , and TiO ₂ .

In the above article, the number of the protrusions per 1 mm ² is preferably 100 or more.

According to the present invention, writing quality when a pen input operation is performed is improved.

Explanatory drawing of a glass article. Scanning electron micrograph of the surface of a glass article. The optical microscope photograph by the transmitted light of the surface of a glass article.

Hereinafter, an embodiment of the present invention will be described.
As shown in FIG. 1, a glass article 10 that is a transparent article includes a glass substrate 11 that is a plate-like transparent substrate. As glass which comprises the glass base material 11, well-known glass, such as an alkali free glass, an aluminosilicate glass, soda-lime glass, can be used, for example. Further, as the glass substrate 11, tempered glass such as chemically tempered glass or crystallized glass such as LAS-based crystallized glass can be used. Of these, aluminosilicate glass is used as the glass substrate 11, and in particular, SiO ₂ : 50 to 80% by mass, Al ₂ O ₃ : 5 to 25% by mass, B ₂ O ₃ : 0 to 15 It is preferable to use chemically tempered glass containing 10% by mass, Na ₂ O: 1 to 20% by mass, and K ₂ O: 0 to 10% by mass.

On one main surface of the glass substrate 11, an antiglare film 12 having an antiglare surface having an uneven structure for scattering light is provided. The concavo-convex structure of the antiglare film 12 and the antiglare surface is constituted by a matrix made of, for example, SiO ₂ , Al ₂ O ₃ , ZrO ₂ , or TiO ₂ . As an example of the concavo-convex structure serving as an antiglare surface, for example, an island-shaped concavo-convex structure having a flat portion between a plurality of island-shaped convex portions can be given. The surface roughness Ra of the surface of the antiglare film 12, that is, the antiglare surface is preferably 5 to 600 nm, for example.

The anti-glare film 12 can be formed, for example, by applying a coating material containing a matrix precursor and a liquid medium dissolving the matrix precursor to the glass substrate 11 and heating. Examples of the matrix precursor contained in the coating agent include inorganic precursors such as a silica precursor, an alumina precursor, a zirconia precursor, and a titania precursor. A silica precursor is preferable because the refractive index of the antiglare film 12 is lowered and the reactivity is easily controlled.

Examples of the silica precursor include a silane compound having a hydrocarbon group and a hydrolyzable group bonded to a silicon atom, a hydrolysis condensate of a silane compound, a silazane compound, and the like. Even when the anti-glare film 12 is formed thick, it is preferable that at least one or both of the silane compound and the hydrolysis condensate thereof is included because cracks of the film can be sufficiently suppressed.

The silane compound has a hydrocarbon group bonded to a silicon atom and a hydrolyzable group. The hydrocarbon group is one or two selected from —O—, —S—, —CO—, and —NR′— (R ′ is a hydrogen atom or a monovalent hydrocarbon group) between carbon atoms. You may have the group which combined two or more.

The hydrocarbon group may be a monovalent hydrocarbon group bonded to one silicon atom or a divalent hydrocarbon group bonded to two silicon atoms. Examples of the monovalent hydrocarbon group include an alkyl group, an alkenyl group, and an aryl group. Examples of the divalent hydrocarbon group include an alkylene group, an alkenylene group, and an arylene group.

Examples of hydrolyzable groups include alkoxy groups, acyloxy groups, ketoxime groups, alkenyloxy groups, amino groups, aminoxy groups, amide groups, isocyanate groups, halogen atoms, and the like. From the viewpoint of balance with ease, an alkoxy group, an isocyanate group, and a halogen atom (especially a chlorine atom) are preferable. As the alkoxy group, an alkoxy group having 1 to 3 carbon atoms is preferable, and a methoxy group or an ethoxy group is more preferable.

Examples of silane compounds include alkoxysilanes (tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, etc.), alkoxysilanes having an alkyl group (methyltrimethoxysilane, ethyltriethoxysilane, etc.), and alkoxysilanes having a vinyl group. (Vinyltrimethoxysilane, vinyltriethoxysilane, etc.), alkoxysilanes having an epoxy group (2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxy Propylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, etc.), alkoxysilanes having an acryloyloxy group (3-acryloyloxypropyltrimethoxysilane, etc.) and the like. Among these silane compounds, it is preferable to use either one or both of alkoxysilane and its hydrolysis condensate, and it is more preferable to use a hydrolysis condensate of alkoxysilane.

The silazane compound is a compound having a silicon-nitrogen bond (—SiN—) in its structure. The silazane compound may be a low molecular compound or a high molecular compound (a polymer having a predetermined repeating unit). Examples of low molecular weight silazane compounds include hexamethyldisilazane, hexaphenyldisilazane, dimethylaminotrimethylsilane, trisilazane, cyclotrisilazane, 1,1,3,3,5,5-hexamethylcyclotrisilazane, etc. Is mentioned.

Examples of the alumina precursor include aluminum alkoxide, hydrolysis condensate of aluminum alkoxide, water-soluble aluminum salt, aluminum chelate and the like. Examples of the zirconia precursor include zirconium alkoxide, a hydrolysis condensate of zirconium alkoxide, and the like. Examples of the titania precursor include titanium alkoxide, hydrolysis condensate of titanium alkoxide, and the like.

The liquid medium contained in the coating agent is a solvent that dissolves the matrix precursor, and is appropriately selected according to the type of the matrix precursor. Examples of the liquid medium include water, alcohols, ketones, ethers, cellosolves, esters, glycol ethers, nitrogen-containing compounds, sulfur-containing compounds and the like.

Examples of alcohols include methanol, ethanol, isopropanol, butanol, diacetone alcohol and the like. Examples of ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone and the like. Examples of ethers include tetrahydrofuran, 1,4-dioxane and the like. Examples of cellosolves include methyl cellosolve and ethyl cellosolve. Examples of esters include methyl acetate and ethyl acetate. Examples of glycol ethers include ethylene glycol monoalkyl ether. Examples of nitrogen-containing compounds include N, N-dimethylacetamide, N, N-dimethylformamide, N-methylpyrrolidone and the like. Examples of the sulfur-containing compound include dimethyl sulfoxide. A liquid medium may be used individually by 1 type, and may be used in combination of 2 or more type.

The liquid medium is preferably a liquid medium containing water, that is, water or a mixed liquid of water and another liquid medium. As other liquid media, alcohols are preferable, and methanol, ethanol, isopropyl alcohol, and butanol are particularly preferable.

The coating agent may contain an acid catalyst that promotes hydrolysis and condensation of the matrix precursor. The acid catalyst is a component that promotes hydrolysis and condensation of the matrix precursor and forms the antiglare film 12 in a short time. Prior to the preparation of the coating agent, the acid catalyst may be added for hydrolysis and condensation of raw materials (alkoxysilane, etc.) during the preparation of the matrix precursor solution. It may be further added after preparation. Examples of the acid catalyst include inorganic acids (such as nitric acid, sulfuric acid, and hydrochloric acid) and organic acids (such as formic acid, oxalic acid, acetic acid, monochloroacetic acid, dichloroacetic acid, and trichloroacetic acid).

Examples of coating methods for coating agents include known wet coating methods (spray coating method, spin coating method, dip coating method, die coating method, curtain coating method, screen coating method, ink jet method, flow coating method, gravure coating method, Bar coating method, flexo coating method, slit coating method, roll coating method, etc.). As a coating method, a spray coating method is preferable from the viewpoint of easily forming irregularities.

Examples of nozzles used in the spray coating method include a two-fluid nozzle and a one-fluid nozzle. The particle size of the coating agent droplets discharged from the nozzle is usually 0.1 to 100 μm, preferably 1 to 50 μm. If the particle size of the droplet is 0.1 μm or more, it is possible to form irregularities that sufficiently exhibit the antiglare effect in a short time. If the particle size of the droplet is 100 μm or less, it is easy to form moderate irregularities that can sufficiently exhibit the antiglare effect. The particle size of the droplets of the coating agent can be appropriately adjusted depending on the type of nozzle, spray pressure, liquid amount, and the like. For example, in a two-fluid nozzle, the higher the spray pressure, the smaller the droplet, and the larger the liquid volume, the larger the droplet. The droplet diameter is the Sauter average particle diameter measured by a laser measuring device.

The surface temperature of the glass substrate 11 when applying the coating agent is, for example, 20 to 75 ° C., preferably 35 ° C. or more, and more preferably 60 ° C. or more. As a method for heating the glass substrate 11, for example, it is preferable to use a warm water circulation type heating device. Further, the humidity at the time of applying the coating agent is, for example, 20 to 80%, preferably 50% or more.

On the outer surface (antiglare surface) of the glass article 10 on the side where the antiglare film 12 is provided, there are cases where protrusions having a height of about 10 to 100 times compared to the uneven structure of the antiglare film 12 are formed. . The protrusions are protrusions having a diameter (average particle diameter) of 1 μm or more and a height of 1 μm or more. When the planar shape of the protrusion is not a circle but a non-circular shape such as an ellipse or a polygon, the diameter of the protrusion is an equivalent circle diameter. The height of the protrusion is preferably 20 μm or less.

In the scanning electron micrograph at a magnification of 20000 shown in FIG. 2, the large protrusions can be confirmed as a granular portion raised from the surface. The height of the protrusion can be confirmed by taking an image with respect to the antiglare surface of the antiglare film 12 with a scanning electron microscope. For example, an image is obtained in a state where an angle formed by an electron beam irradiation direction of a scanning electron microscope and one main surface of the glass substrate 11 on which the antiglare film 12 is formed is 17 °. The actual height of the protrusion can be obtained by obtaining the height H of the protrusion at and dividing the height H by “cos 17 °”. It is considered that the protrusions are formed when the antiglare film 12 is formed by aggregating and granulating the film forming material and adhering to the surface (antiglare surface) of the antiglare film 12.

In the glass article 10 of the present embodiment, the number of protrusions per unit area of the antiglare surface in the antiglare film 12 is set to a specific value or more. That is, the number of the protrusions per 1 mm ² in the glass article 10 is 50 or more. And the number per 1 mm < ² > of the said protrusion becomes like this. Preferably it is 76 or more, More preferably, it is 100 or more, More preferably, it is 300 or more. By setting the number of the protrusions in this way, the pen tip is appropriately caught on the protrusion, and the same writing feeling as when writing characters or the like on the actual paper can be obtained. That is, the writing quality when a pen input operation is performed is improved. In addition, although the upper limit of the number per 1 mm < ² > of the said protrusion in the glass article 10 is not specifically limited, For example, it is preferable that it is 1500 pieces, it is more preferable that it is 1000 pieces, and it is 500 pieces. Is more preferable. FIG. 3 is an optical micrograph of transmitted light with a magnification of 200 times (objective lens 20 times, eyepiece lens 10 times). In the optical micrograph, the protrusions can be confirmed as black dots.

The number of protrusions can be controlled by changing the film formation conditions of the antiglare film 12. For example, when the antiglare film 12 is formed by applying a coating agent by a spray coating method, the distance from the nozzle to the glass substrate 11 that is a film formation target (hereinafter referred to as a spray distance) is changed. As a result, the number of the protrusions also changes. The inventor's research has revealed that there is an appropriate range for the spray distance, and that the protrusions are reduced outside the range. The appropriate spray distance varies depending on the type of coating agent, viscosity, and spray conditions (temperature, humidity), but in order to increase the number of protrusions, it is better to set the spray distance longer, for example, 60 mm or more. It is preferable to set. In addition, although the upper limit of spray distance is not specifically limited, For example, it is preferable that it is 200 mm. The number of protrusions can also be increased by setting the surface temperature of the glass substrate 11 when applying the coating agent and the humidity when applying the coating agent within the above-mentioned range.

The glass article 10 of this embodiment is used by being arranged on the input surface of the pen input device. The glass article 10 may be a member attached on the input surface of the pen input device. That is, the glass article 10 may be a member that is attached to the pen input device afterwards.

Next, the effect of this embodiment will be described.
(1) A glass article 10 which is a transparent article used for a part where a pen input operation is performed includes a glass substrate 11 which is a transparent substrate and an antiglare film 12 provided on the glass substrate 11. Yes. The number per 1 mm ^{2 of} protrusions having a diameter of 1 μm or more and a height of 1 μm or more present on the surface of the antiglare film 12, that is, the antiglare surface, is 50 or more. According to the above configuration, the writing quality when a pen input operation is performed is improved.

(2) If the number of protrusions per 1 mm ² is 100 or more, the writing quality when performing a pen input operation is further improved.
(3) If the spray distance when forming the anti-glare film 12 by applying a coating agent containing a matrix precursor to the glass substrate 11 by a spray coating method is 60 mm or more, it is formed on the surface of the glass article 10 It is possible to increase the number of protrusions to be formed. Therefore, it is possible to easily manufacture the glass article 10 that is excellent in writing when a pen input operation is performed.

In addition, this embodiment can also be changed and embodied as follows.
-An anti-glare film having an anti-glare surface may be provided on two or more of the surfaces of the substrate.

Other layers such as an antireflection layer and an antifouling layer may be provided between the substrate and the antiglare film and at least one on the antiglare film.
-As a transparent base material, instead of the glass base material 11, you may use resin base materials, such as a polycarbonate base material.

-Although the anti-glare surface in the said embodiment is formed of the anti-glare film | membrane 12 formed by apply | coating a coating agent to the glass base material 11 and heating, an anti-glare surface etch-processes the surface of the glass base material 11 May be formed.

Next, the technical idea that can be grasped from the embodiment and the modified examples will be described.
-The transparent article in which the anti-glare surface is constituted by an anti-glare film applied by a wet coat method.

-Per 1 mm ^{2 of} protrusions having a diameter of 1 μm or more and a height of 1 μm or more present on the surface of a transparent article comprising a transparent substrate and an antiglare surface provided on at least one surface of the transparent substrate An evaluation method for evaluating the writing quality of the surface of a transparent article based on the number.

A method for producing a transparent article used in a site where a pen input operation is performed, the transparent article comprising a transparent substrate and an antiglare surface provided on at least one surface of the transparent substrate;
The antiglare surface is the surface of an antiglare film, and the antiglare film is formed by applying a coating agent containing a matrix precursor to the transparent substrate by a spray coating method, and the coating agent is formed by a spray coating method. A method for producing a transparent article, wherein a spray distance during application is 60 mm or more.

(Test Examples 1 to 14)
Glass articles of Test Examples 1 to 14 having different antiglare film forming conditions were produced. That is, with a spray coating apparatus having a nozzle diameter of 0.6 mm on the surface of a glass substrate (Nippon Electric Glass Co., Ltd .: Dinorex (registered trademark)) made of tempered glass having a length of 150 mm, a width of 300 mm, and a thickness of 1.1 mm. Then, an antiglare film was formed by applying a coating agent prepared by dissolving a precursor of an antiglare film (tetraethyl orthosilicate) in a liquid medium containing water. The coating amount per unit area of the coating agent on the glass substrate was 3 × 10 ⁻⁵ g / mm ² . Table 1 shows the atmospheric temperature, atmospheric humidity, spray moving speed (nozzle moving speed), and spray distance during film formation.

(Measurement of the number of protrusions)
For the glass articles of Test Examples 1 to 14, the number of protrusions present on the antiglare surface of the antiglare film and having a diameter of 1 μm or more and a height of 1 μm or more was measured. The number of protrusions was measured by counting the number of black spots as shown in FIG. 3 using an optical microscope (200 times magnification). Specifically, five areas of 1 mm ² (1 mm long × 1 mm wide) were randomly selected from the antiglare surface, the number of the protrusions present in each of these areas was counted, and the average value was calculated. . The results are shown in Table 1.

(Evaluation of writing quality)
Thirty panelists were asked to draw on the surface of the glass article of each test example using an input pen (Wacom: Propen (KP-503E)), and feel good writing with a texture close to paper It was evaluated whether or not. The results are shown in the “writing quality” column of Table 1. In the “writing quality” column, “◎” indicates that the number of people who evaluated that the writing quality is good is 26 or more, and “○” indicates that the number of people evaluated that the writing quality is good is 21 or more and 25 or less. “△” indicates that the number of people evaluated that writing quality is good is 16 or more and 20 or less, and “×” indicates that the number of people evaluated that writing quality is good is 15 or less.

As shown in Table 1, it can be seen that the number of protrusions having a diameter of 1 μm or more and a height of 1 μm or more increases as the spray distance increases. Further, the number of protrusions per 1 mm ² is compared to the test examples 7 to 14 is less than 50, Test Examples 1 to 6 above projections per 1 mm ² is 50 or more, the evaluation of writing taste The result was high. Among Test Examples 1 to 6, Test Examples 1 to 4 in which the number of protrusions per 1 mm ² is 100 or more, particularly Test Example 1 in which the number of protrusions per 1 mm ² is 300 or more are written. The taste evaluation was very high. From this result, it can be seen that the writing quality when the pen input operation is performed changes according to the number of protrusions. Further, by making the number of the protrusions per 1 mm ² to 50 or more, it can be seen that becomes the writing feeling when performing the pen input operation is excellent.

10 ... Glass article, 11 ... Glass substrate, 12 ... Anti-glare film.

Claims (3)

1. An article used for a part where a pen input operation is performed,
   A substrate and an anti-glare surface provided on at least one surface of the substrate;
   An article characterized in that the number per 1 mm ^{2 of} protrusions having a diameter of 1 μm or more and a height of 1 μm or more present on the antiglare surface is 50 or more.
2. The anti-glare surface _The article of claim 1, characterized in that it is constituted by an anti-glare film containing at least one selected from _{SiO 2, Al 2 O 3,} ZrO 2, TiO 2.
3. The article according to claim 1 or 2, wherein the number of the projections per 1 mm ² is 100 or more.

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