JP6866743B2 - Half mirror - Google Patents

Description

The present invention relates to a half mirror for a mirror device having an image display function.

As disclosed in Patent Document 1, a mirror device having an image display function includes an image display device and a half mirror provided on the front side of the image display device. The half mirror of such a mirror device functions as a mirror surface for displaying a reflected image when the image is not displayed, and functions as a display surface for transmitting and projecting the image output from the image display device when displaying the image.

Japanese Unexamined Patent Publication No. 2016-135667

By the way, a half mirror for a mirror device having an image display function improves the visibility of a transmitted image (image) projected when an image is displayed while ensuring the visibility of a reflected image (mirror image) projected when the image is not displayed. Is an issue. That is, in order to improve the visibility of the transmitted image projected at the time of displaying an image, it is preferable to reduce the reflection of the reflected image on the surface of the half mirror. However, if the reflection of the reflected image is reduced as much as possible, the reflected image projected when the image is not displayed becomes blurred, and its visibility is greatly reduced.

The present invention has been made in view of such circumstances, and an object of the present invention is to suppress a decrease in visibility of a reflected image projected when an image is not displayed with respect to a half mirror for a mirror device having an image display function. The purpose is to suppress the reflection of the reflected image when the image is displayed.

The half mirror for achieving the above object is a half mirror for a mirror device having an image display function, has a first main surface and a second main surface, and has the first main surface side to the second main surface. An anti-glare layer, a transparent base material layer, and a half mirror layer are provided in this order toward the main surface side, and the gloss value of the first main surface is 350 to 420.

The half mirror for achieving the above object is a half mirror for a mirror device having an image display function, has a first main surface and a second main surface, and has the first main surface side to the second main surface. An anti-glare layer, a half mirror layer, and a transparent base material layer are provided in this order toward the main surface side, and the gloss value of the first main surface is 300 to 380.

In the half mirror, the anti-glare layer is preferably composed of a matrix composed of at least one selected from _{SiO 2} , Al ₂ O ₃ , ZrO ₂ , and TiO _2.

In the above half mirror, the haze value is preferably 6% or less.

According to the present invention, it is possible to suppress the reflection of the reflected image when the image is displayed while suppressing the deterioration of the visibility of the reflected image projected when the image is not displayed.

Schematic of the mirror device. (A) and (b) are explanatory views which show the layer structure of a half mirror.

Hereinafter, an embodiment of the present invention will be described.
As shown in FIG. 1, the half mirror 10 of the present embodiment is used as a mirror portion of a mirror device 20 having an image display function. Examples of applications of the mirror device 20 having an image display function include vehicle applications such as inner mirrors, window glass applications, and building material applications. Further, the mirror device 20 may have a touch panel function in addition to the video display function.

The mirror device 20 includes a housing 21, an image display device 22 provided inside the housing 21, and a half mirror 10 attached to the housing 21 so as to be located on the front surface 22a side of the image display device 22. As the image display device 22, for example, a known image display device such as a liquid crystal display device, an organic EL display device, or a plasma display device can be used. The image display device 22 and the half mirror 10 may or may not be in contact with each other. From the viewpoint of light utilization efficiency and image visibility, it is preferable that a filler 23 such as a transparent resin is filled between the image display device 22 and the half mirror 10 so that both members are brought into close contact with each other.

As shown in FIG. 1, the half mirror 10 is a flat plate-like member having a first main surface 11 and a second main surface 12 located on the opposite side of the first main surface 11. The first main surface 11 side of the half mirror 10 is located on the outside of the mirror device 20 (user side), and the second main surface 12 side thereof is located on the inside of the mirror device 20 (image display device 22 side). Be placed.

As shown in FIGS. 2 (a) and 2 (b), the half mirror 10 has a transparent base material layer 13, a half mirror layer 14, and an anti-glare layer 15, and each of these layers is arranged in a specific order. It has a layered structure. As shown in FIG. 2A, the arrangement order of the layers in the half mirror 10 is as follows: "anti-glare layer 15"-"transparent base material layer 13" from the first main surface 11 side to the second main surface 12 side. -In the order of "half mirror layer 14", or as shown in FIG. 2B, from the first main surface 11 side to the second main surface 12 side, "anti-glare layer 15"-"half mirror layer 14" -The order is "transparent base material layer 13". As shown in FIG. 2A, the order of "anti-glare layer 15"-"transparent base material layer 13"-"half mirror layer 14" is more preferable.

The transparent base material layer 13 is a layer made of a translucent transparent base material. The thickness of the transparent base material layer 13 is, for example, 0.05 to 2.0 mm. Examples of the material of the transparent base material layer 13 include glass and resin. The material of the transparent base material layer 13 is preferably glass, and as the glass, for example, known glass such as non-alkali glass, aluminosilicate glass, and soda lime can be used. Further, tempered glass such as chemically strengthened glass and crystallized glass such as LAS-based crystallized glass can be used. Among these, aluminosilicate glass is used, in particular, in terms of mass%, SiO ₂ : 50 to 80%, Al ₂ O ₃ : 5 to 25%, B ₂ O ₃ : 0 to 15%, Na ₂ O: _1~20%, K 2 O: it is preferable to use a chemically strengthened glass containing 0-10%. Examples of the resin include polymethyl methacrylate, polycarbonate, and epoxy resin.

The half mirror layer 14 is a layer that transmits a part of the incident light and reflects a part of the incident light. Examples of the half mirror layer 14 include known half mirror layers such as a half mirror layer made of a dielectric multilayer film and a half mirror layer made of a semitransparent metal film. When applied to the mirror device 20 having a touch panel function, it is preferable to use the half mirror layer 14 made of a dielectric multilayer film because it is difficult to absorb visible light.

The dielectric multilayer film has a structure in which a high refractive index film and a low refractive index film having a lower refractive index than the high refractive index film are alternately laminated. Examples of the high refractive index film include at least one selected from niobium oxide, titanium oxide, tantalum oxide, lanthanum oxide, tungsten oxide, and zirconium oxide. The high refractive index film preferably contains niobium oxide. Examples of the low refractive index film include at least one selected from silicon oxide and aluminum oxide. The low refractive index film preferably contains silicon oxide.

The thickness of the dielectric multilayer film is, for example, 200 to 400 nm. The total number of layers of the high-refractive index film and the low-refractive index film in the dielectric multilayer film is, for example, 4 layers or more and 60 layers or less. In the dielectric multilayer film, a gradual transition layer in which the refractive index gradually decreases or gradually increases from the high refractive index film to the low refractive index film may be provided between the high refractive index film and the low refractive index film. Further, a gradual transition layer in which the refractive index gradually decreases from the dielectric multilayer film to the transparent base material layer 13 may be provided on the transparent base material layer 13 side of the half mirror layer 14. Further, in addition to the high refractive index film and the low refractive index film, a medium refractive index film having a refractive index smaller than that of the high refractive index film and larger than that of the low refractive index film may be provided.

The dielectric multilayer film can be formed on the surface of the transparent base material layer 13 by using a known film forming method such as a sputtering method, a vacuum vapor deposition method, an ion beam method, an ion plating method, or a CVD method. .. Among these film forming methods, the sputtering method is preferable because the thickness of each layer can be controlled with high accuracy and a dielectric multilayer film having a stable film quality can be obtained.

Examples of the material of the semi-transmissive metal film include at least one selected from titanium, aluminum, silver, and tin. Of these, titanium is particularly preferred.
The thickness of the semi-permeable metal film is preferably 10 to 80 nm, for example.

The translucent metal film can be formed on the surface of the transparent base material layer 13 by using a known film forming method such as a sputtering method, a vacuum vapor deposition method, an ion beam method, an ion plating method, or a CVD method. it can. Among these film forming methods, the sputtering method is preferable because the thickness can be controlled with high accuracy and a semi-permeable metal film having a stable film quality can be obtained.

The anti-glare layer 15 is a layer having a surface (anti-glare surface) having an uneven structure that scatters light. The anti-glare layer 15 and its uneven structure are composed of, for example, a matrix composed of _{SiO 2} , Al ₂ O ₃ , ZrO ₂ , and TiO _2. Examples of the uneven structure as the anti-glare surface include an island-shaped uneven structure having a flat portion between a plurality of island-shaped convex portions.

The anti-glare layer 15 can be formed, for example, by applying a coating agent containing a matrix precursor and a liquid medium that dissolves the matrix precursor to the surface of the transparent base material layer 13 or the surface of the half mirror layer 14 and heating the layer. .. Examples of the matrix precursor contained in the coating agent include inorganic precursors such as silica precursor, alumina precursor, zirconia precursor, and titania precursor. A silica precursor is preferable because it lowers the refractive index of the anti-glare layer 15 and makes it easy to control the reactivity.

Examples of the silica precursor include a silane compound having a hydrocarbon group and a hydrolyzable group bonded to a silicon atom, a hydrolyzed condensate of the silane compound, and a silazane compound. It is preferable to contain at least one or both of the silane compound and its hydrolyzed condensate from the viewpoint that cracks in the anti-glare layer 15 are sufficiently suppressed even when the anti-glare layer 15 is formed thickly.

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. It may have a group in which one or more are combined.

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, an aryl group and the like. Examples of the divalent hydrocarbon group include an alkylene group, an alkaneylene group, an arylene group and the like.

Examples of the hydrolyzable group include an alkoxy group, an asyloxy group, a ketooxime group, an alkenyloxy group, an amino group, an aminoxic group, an amide group, an isocyanate group, a halogen atom and the like, and the stability of the silane compound and the ease of hydrolysis Alkoxy groups, isocyanate groups, and halogen atoms (particularly chlorine atoms) are preferable from the viewpoint of balance with the group. 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 the silane compound include alkoxysilane (tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, etc.), alkoxysilane having an alkyl group (methyltrimethoxysilane, ethyltriethoxysilane, etc.), and alkoxysilane having a vinyl group (vinyl). (Trimethoxysilane, vinyltriethoxysilane, etc.), alkoxysilane having an epoxy group (2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyl) Diethoxysilane, 3-glycidoxypropyltriethoxysilane, etc.), alkoxysilane having an acryloyloxy group (3-acryloyloxypropyltrimethoxysilane, etc.) and the like can be mentioned. Among these silane compounds, it is preferable to use either one or both of the alkoxysilane and the hydrolyzed condensate of the alkoxysilane, and it is more preferable to use the hydrolyzed condensate of the alkoxysilane.

A silazane compound is a compound having a silicon-nitrogen bond (-SiN-) in its structure. The silazane compound may be a low molecular weight compound or a high molecular weight compound (a polymer having a predetermined repeating unit). Examples of the low molecular weight silazane compound include hexamethyldisilazane, hexaphenyldisilazane, dimethylaminotrimethylsilane, trisilazane, cyclotrisilazane, 1,1,3,3,5,5-hexamethylcyclotrisilazane and the like. Be done.

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

The liquid medium contained in the coating agent is a solvent that dissolves the matrix precursor, and is appropriately selected depending on 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 the 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 the esters include methyl acetate, ethyl acetate and the like. Examples of glycol ethers include ethylene glycol monoalkyl ethers. Examples of the nitrogen-containing compound include N, N-dimethylacetamide, N, N-dimethylformamide, N-methylpyrrolidone and the like. Examples of the sulfur-containing compound include dimethyl sulfoxide and the like. As the liquid medium, one type may be used alone, or two or more types may be used in combination.

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

Further, 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 to form the anti-glare layer 15 in a short time. The acid catalyst may be added for hydrolysis or condensation of the raw material (alkoxysilane, etc.) at the time of preparing the solution of the matrix precursor prior to the preparation of the coating agent, and may contain essential components. It may be further added after preparation. Examples of the acid catalyst include inorganic acids (nitric acid, sulfuric acid, hydrochloric acid, etc.) and organic acids (formic acid, oxalic acid, acetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, etc.).

As a coating method, known wet coating methods (spray coating method, spin coating method, dip coating method, die coating method, curtain coating method, screen coating method, inkjet method, flow coating method, gravure coating method, bar coating) Method, flexo coat method, slit coat method, roll coat method, etc.) and the like. As a coating method, a spray coating method is preferable because unevenness is easily formed.

Examples of the nozzle 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. When the particle size of the droplet is 0.1 μm or more, unevenness on which the antiglare effect is sufficiently exhibited can be formed in a short time. When the particle size of the droplet is 100 μm or less, it is easy to form appropriate unevenness in which the antiglare effect is sufficiently exhibited. The particle size of the droplets of the coating agent can be appropriately adjusted depending on the type of nozzle, spray pressure, amount of liquid, and the like. For example, in a two-fluid nozzle, the higher the spray pressure, the smaller the droplets, and the larger the amount of liquid, the larger the droplets. The particle size of the droplet is the Sauter average particle size measured by a laser measuring device.

The surface temperature of the object to be coated (for example, a transparent base material) when the coating agent is applied is, for example, 20 to 75 ° C., preferably 35 ° C. or higher, and more preferably 60 ° C. or higher. As a method of heating the object to be coated, for example, it is preferable to use a hot water circulation type heating device. The humidity when applying the coating agent is, for example, 20 to 80%, preferably 50% or more.

The total transmittance of the half mirror 10 is preferably 20% to 80%, more preferably 30% to 70%, and further preferably 40% to 60%. The total transmittance of the half mirror 10 is, for example, the thickness of the dielectric multilayer film or the semitransparent metal film constituting the half mirror layer 14, and the total lamination of the high refractive index film and the low refractive index film in the dielectric multilayer film. It can be adjusted by controlling the number.

The gloss value and haze value of the half mirror 10 are set in specific ranges, respectively.
The gloss value of the half mirror 10 is a gloss value at an incident angle of 60 ° on the first main surface 11, and is a value measured in accordance with JIS Z8741 (1997). The gloss value is 350 to 420, preferably 360 to 410, in the half mirror 10 of FIG. 2A. Further, in the half mirror 10 of FIG. 2B, the gloss value is 300 to 380, preferably 310 to 370.

The gloss value can be controlled by changing the formation conditions of the anti-glare layer 15. For example, when the anti-glare layer 15 is formed by the spray coating method, if the coating amount applied per unit time is increased, the gloss value tends to decrease, and if the coating amount applied per unit time is decreased, the gloss value tends to decrease. , Gross values tend to increase.

The haze value of the half mirror 10 is a haze value when light is incident from the first main surface 11 side to the second main surface 12 side of the half mirror 10, and is measured in accordance with JIS K7136 (2000). Value. The haze value is preferably 6% or less, and more preferably 4% or less. The haze value can be controlled by changing the formation conditions of the anti-glare layer 15. For example, when the anti-glare layer 15 is formed by the spray coating method, the haze value tends to decrease when the amount of the coating agent applied per unit time is decreased.

Next, the operation and effect of this embodiment will be described.
(1) The half mirror 10 having the first main surface 11 and the second main surface 12 has an anti-glare layer 15, a transparent base material layer 13, and a half mirror from the first main surface 11 side to the second main surface 12 side. The layers 14 are provided in order and have a gloss value of 350 to 420, preferably a haze value of 6% or less.

In the half mirror 10 having the first main surface 11 and the second main surface 12, the anti-glare layer 15, the half mirror layer 14, and the transparent base material layer 13 are formed from the first main surface 11 side to the second main surface 12 side. They are provided in order, and the gloss value is 300 to 380, preferably the haze value is 6% or less.

According to the above configuration, in the anti-glare layer 15 provided on the first main surface 11 side (user side) of the transparent base material layer 13 and the half mirror layer 14, reflection on the first main surface 11 side of the half mirror 10 Is diffused, so that the reflection of the reflected image is suppressed. This improves the visibility of the image projected when the image is displayed. Then, by setting the gloss value of the half mirror 10 in the above range, preferably further setting the haze value in the above range, even when the anti-glare layer 15 is provided, the half mirror is not displayed when the image is hidden. The visibility of the mirror image projected on the 11th side of the first main surface of 10 is good.

(2) The anti-glare layer 15 is composed of a matrix composed of at least one selected from _{SiO 2} , Al ₂ O ₃ , ZrO ₂ , and TiO _2. In this case, the effect of (1) above can be obtained more reliably.

The present embodiment can be modified and embodied as follows.
The half mirror 10 may have other layers in addition to the transparent base material layer 13, the half mirror layer 14, and the anti-glare layer 15. As another layer, for example, an antifouling (AF) layer may be provided on the most first main surface 11 side of the half mirror 10.

-The anti-glare layer 15 is not limited to a shape having an anti-glare surface having an island-shaped uneven structure. For example, the anti-glare layer 15 may have an anti-glare surface having an uneven structure formed on the surface of the transparent base material layer 13, the half mirror layer 14, or the like by another method such as a blast treatment or an etching treatment.

Next, the technical idea that can be grasped from the above-described embodiment and modified example will be described below.
(A) A mirror device including a video display device and a half mirror provided on the front side of the video display device, wherein the half mirror is a first main surface located on the opposite side of the video display device and the said. It has a second main surface located on the image display device side, and an anti-glare layer, a transparent base material layer, and a half mirror layer are provided in this order from the first main surface side toward the second main surface side. A mirror device having a gloss value of 350 to 420 on the first main surface and a haze value of 6% or less.

(B) A mirror device including a video display device and a half mirror provided on the front side of the video display device, wherein the half mirror is a first main surface located on the opposite side of the video display device and the said. It has a second main surface located on the image display device side, and an anti-glare layer, a half mirror layer, and a transparent base material layer are provided in this order from the first main surface side toward the second main surface side. A mirror device having a gloss value of 300 to 380 on the first main surface and a haze value of 6% or less.

The above embodiment will be described in more detail with reference to test examples below. The present invention is not limited thereto.
(Test Example 1)
A half mirror of Test Example 1 in which a half mirror layer and a transparent base material layer were provided in this order from the first main surface side to the second main surface side was produced.

From niobium oxide and silicon oxide using a sputtering method on one surface, which is the first main surface side, of a plate-shaped glass substrate (manufactured by Nippon Electric Glass Co., Ltd .: T2X-1) having a thickness of 1.1 mm. A half mirror layer having a thickness of 495 nm was formed by laminating the dielectric multilayer films.

(Test Examples 2 to 6)
Half mirrors of Test Examples 2 to 6 in which an anti-glare layer, a transparent base material layer, and a half mirror layer were provided in this order from the first main surface side to the second main surface side were produced.

A spray coating device with a nozzle diameter of 0.6 mm was applied to the surface of one side of a plate-shaped glass substrate (manufactured by Nippon Electric Glass Co., Ltd .: T2X-1) having a thickness of 1.1 mm, which is the first main surface side. An anti-glare layer was formed by applying a coating agent prepared by dissolving a precursor of the anti-glare layer (tetraethyl orthosilicate) in a liquid medium containing water. The amount of the coating agent applied to the glass substrate per unit area was 3 × ^10-5 g / mm ² . The atmospheric temperature at the time of forming the anti-glare layer was 20 ° C., the atmospheric humidity was 60%, the spray moving speed (nozzle moving speed) was 40 m / min, and the spray distance was 60 mm.

Further, a half mirror layer having a thickness of 495 nm is formed by laminating a dielectric multilayer film made of niobium oxide and silicon oxide on the surface of the other side, which is the second main surface side of the glass substrate, by using a sputtering method. Formed. As shown in Table 1, Test Examples 2 to 6 have different coating amounts per unit time.

(Test Examples 7 to 11)
Half mirrors of Test Examples 7 to 11 in which an anti-glare layer, a half mirror layer, and a transparent base material layer were provided in this order from the first main surface side to the second main surface side were produced.

From niobium oxide and silicon oxide using a sputtering method on one surface, which is the first main surface side, of a plate-shaped glass substrate (manufactured by Nippon Electric Glass Co., Ltd .: T2X-1) having a thickness of 1.1 mm. A half mirror layer having a thickness of 495 nm was formed by laminating the dielectric multilayer films.

A coating agent prepared by dissolving a precursor of an antiglare layer (tetraethyl orthosilicate) in a liquid medium containing water is applied to the surface of the formed half mirror layer by a spray coating device having a nozzle diameter of 0.6 mm. By doing so, an anti-glare layer was formed. The amount of the coating agent applied to the half mirror layer per unit area was 3 × 10 ^-5 g / mm ² . The atmospheric temperature at the time of forming the anti-glare layer was 20 ° C., the atmospheric humidity was 60%, the spray moving speed (nozzle moving speed) was 40 m / min, and the spray distance was 60 mm.

As shown in Table 1, Test Examples 7 to 11 have different coating amounts per unit time.
(Test Example 12)
A half mirror of Test Example 12 in which a half mirror layer, an anti-glare layer, and a transparent base material layer were provided in this order from the first main surface side to the second main surface side was produced.

A spray coating device with a nozzle diameter of 0.6 mm was applied to the surface of one side of a plate-shaped glass substrate (manufactured by Nippon Electric Glass Co., Ltd .: T2X-1) having a thickness of 1.1 mm, which is the first main surface side. An anti-glare layer was formed by applying a coating agent prepared by dissolving a precursor of the anti-glare layer (tetraethyl orthosilicate) in a liquid medium containing water. The amount of the coating agent applied to the glass substrate per unit area was 3 × ^10-5 g / mm ² . The atmospheric temperature at the time of forming the anti-glare layer was 20 ° C., the atmospheric humidity was 60%, the spray moving speed (nozzle moving speed) was 40 m / min, and the spray distance was 60 mm.

A half mirror layer having a thickness of 495 nm was formed by laminating a dielectric multilayer film composed of niobium oxide and silicon oxide on the surface of the formed anti-glare layer by a sputtering method.

(Measurement of gross value)
According to JIS Z8741 (1997), the gloss value at an incident angle of 60 ° on the first main surface of the half mirrors of Test Examples 1 to 12 was measured. The results are shown in Table 1.

(Measurement of haze value)
The haze value of the half mirrors of Test Examples 1 to 12 was measured according to JIS K7136 (2000). In addition, this measurement was performed by injecting light from the first main surface side of the half mirror toward the second main surface side. The results are shown in Table 1.

(sensory evaluation)
The half mirrors of each test example were arranged on the display surface of the image display device (manufactured by Apple Inc .: iPad (registered trademark)) so that the second main surface faces the image display device side. With the image display device activated and the image (transmission image) displayed on the half mirror, the first main surface of the half mirror is visually observed (photopic vision) to evaluate the visibility of the image when the image is displayed. did. The results are shown in the "Video Visibility" column of Table 1.

The visibility of the image was evaluated by 30 panelists, and those with 26 or more panelists who evaluated that "the image is clear and there is little reflection" are "◎", and the number is 21. Those with 25 or more people were evaluated as "○", those with 16 or more and 20 or less were evaluated as "Δ", and those with 15 or less were evaluated as "x".

In addition, with the image display device inoperable and a mirror image (reflected image) displayed on the first main surface of the half mirror, the first main surface of the half mirror is visually observed (photopic vision), and the image is not displayed. The visibility of the mirror image at the time of display was evaluated. The results are shown in the "Mirror image visibility" column of Table 1.

The visibility of the mirror image was evaluated by 30 panelists, and those with 25 or more panelists who evaluated that the mirror image was clear were marked with "◎", and the number of people was 21 or more and 25 or less. Those with "○" were evaluated as "○", those with 16 or more and 20 or less were evaluated as "Δ", and those with 15 or less were evaluated as "×".

表１の「層構造欄」における「Ｇ」は透明基材層を示し、「ＨＭ」はハーフミラー層を示し、「ＡＧ」はアンチグレア層を示す。

In the "layer structure column" of Table 1, "G" indicates a transparent base material layer, "HM" indicates a half mirror layer, and "AG" indicates an anti-glare layer.

As shown in Table 1, in Test Example 1 in which the anti-glare layer was not provided, the visibility of the image was poor due to the strong reflection.
On the other hand, Test Examples 2 to 6 have a layer structure in the order of arrangement of "anti-glare layer"-"transparent base material layer"-"half mirror layer" from the first main surface side to the second main surface side. From the results of the above, it can be seen that when the gloss value is 350 to 420, the visibility of the image and the visibility of the mirror image are very excellent while suppressing the reflection at the time of displaying the image by the anti-glare layer. .. The haze value in this case was 6% or less.

Further, from the results of Test Examples 7 to 11, which are layer structures in the order of arrangement of "anti-glare layer"-"half mirror layer"-"transparent base material layer" from the first main surface side to the second main surface side. When the gloss value is 300 to 380, it can be seen that the visibility of the image and the visibility of the mirror image are excellent while suppressing the reflection at the time of displaying the image by the anti-glare layer. The haze value in this case was 6% or less.

On the other hand, Test Example 12, which has a layer structure in the order of arrangement of "half mirror layer"-"anti-glare layer"-"transparent base material layer" from the first main surface side to the second main surface side, is the first main surface. Light was greatly diffused in the half mirror layer located on the surface side, and both the image and the mirror image became blurry and unclear.

Based on these results, by adopting a layered structure in a specific arrangement order and setting the gloss value to a specific range, reflection during image display is suppressed while suppressing deterioration of visibility of the mirror image projected when the image is not displayed. It can be seen that the reflection of the image can be suppressed.

10 ... Half mirror, 11 ... 1st main surface, 12 ... 2nd main surface, 13 ... Transparent substrate layer, 14 ... Half mirror layer, 15 ... Anti-glare layer, 20 ... Mirror device, 21 ... Housing, 22 ... Video display Equipment, 22a ... front surface, 23 ... filler.

Claims (4)

Used in a mirror device having an image display function, it is located on the front side of the image display device and projects a reflected image when the image display device does not display a non-image, and outputs the reflected image when the image is displayed by the image display device. It is a half mirror that transmits and projects the image to be displayed.
It has a first main surface and a second main surface, and is used by being arranged so that the second main surface side is located on the image display device side.
An anti-glare layer, a transparent base material layer, and a half mirror layer are provided in this order from the first main surface side to the second main surface side.
A half mirror characterized in that the gloss value of the first main surface is 350 to 420. Used in a mirror device having an image display function, it is located on the front side of the image display device and projects a reflected image when the image display device does not display a non-image, and outputs the reflected image when the image is displayed by the image display device. It is a half mirror that transmits and projects the image to be displayed.
It has a first main surface and a second main surface, and is used by being arranged so that the second main surface side is located on the image display device side.
An anti-glare layer, a half mirror layer, and a transparent base material layer are provided in this order from the first main surface side to the second main surface side.
A half mirror characterized in that the gloss value of the first main surface is 300 to 380. _{The half mirror according to claim 1 or 2} , wherein the anti-glare layer is composed of a matrix composed of at least one selected from SiO 2, Al ₂ O ₃ , ZrO ₂ , and TiO _2. The half mirror according to any one of claims 1 to 3, wherein the haze value is 6% or less.

Images