JP2002023670A - Light-transmissive display plate and electronic display device provided with it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily manage dimensions of small holes and to reduce the manufacturing cost. SOLUTION: A metallic film 3 in which many small holes having about 40 to 70 μm diameter are dispersively arranged at prescribed intervals at about 20 to 50% area rate of the surface area is arranged on the lower face of a transmissive display substrate 2 to constitute a light-transmissive display plate 4. Since small holes 3a can be formed by print of a resist film and peeling in a post-stage by design of about 40 to 70 μm diameter, a manufacturing method is easy and they are manufactured at a low cost. Since the metallic film 3 is arranged on the lower face of the transmissive display plate 2 or the transmissive display substrate is ornamented by coloring or the like, small holes 3a cannot be seen by naked eyes. Since the area rate of small holes 3a is set to about 20 to 50%, the power generation function of a solar cell is sufficiently displayed, and sufficient illumination is obtained even if a back light like an EL is used. Since the metallic film 3 can be made thick, various rugged patterns can be formed to not only enhance decorativeness but also increase ornament variations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dial structure having a solar cell or a backlight and a liquid crystal display structure having a backlight, and more particularly to a light-transmitting display plate and an electronic display device having the same.

[0002]

2. Description of the Related Art In recent years, portable information processing apparatuses and the like which have been reduced in size have been used. In this type of device, as an electronic display device, there is a device in which an EL is provided on a watch to emit light when it is dark to illuminate the display panel of the watch, or a device in which a solar cell is incorporated to drive the watch. Some mobile phones and the like are also provided with a backlight such as an EL or LED and emit light when dark to illuminate the display.

The display panel provided with the EL and the solar panel provided with a solar cell often use a plastic plate, a glass plate, or the like because light transmittance is required. Various methods have been adopted to decorate this plastic plate or glass plate to give it a decorative variation or a high-grade appearance. However, the display plate has a poor metallic appearance and lacks a high-quality appearance.

As a method of solving this method, for example,
JP-A-11-326549 and JP-A-11-31780 disclose a technique in which a metal plate having invisible small holes is provided on a display plate. ing.

According to the above-mentioned Japanese Patent Application Laid-Open No. H11-326549, "Timepiece dial", as shown in FIGS. 3 and 4, the structure of the timepiece display plate 20 is a transparent display plate made of a transparent resin plate or the like. A metal film 22 having a large number of small holes 22a that cannot be visually recognized is provided on the upper surface side of the substrate 21, and indices 23 such as hour marks and marks are provided at predetermined positions. 22 is coated with a clear coating 24 to prevent corrosion and damage. A solar cell 25 (or EL) is provided below the clock display panel 20. The metal film 22 has a two-layer structure (the upper layer is made of silver metal and the lower layer is made of nickel metal), and small holes 22a having a hole diameter of about 5 to 30 μm are formed on the surface thereof.
Are uniformly distributed at an area ratio of about 20 to 50% of the entire surface area of the metal film 22. The small holes 22a are accurately formed by a manufacturing method based on an electrohoming method.

A brief description will be given of a manufacturing method using the above-described electrohoming method. First, a resist film is printed on a flat stainless steel flat plate. The resist film is exposed by a photographic exposure device, and a portion other than the desired small hole formation, that is, a removed portion is removed by a resist removing device. A parting process is performed on the part where the resist film is removed to form a release film. Nickel plating is performed on the release coating by a plating apparatus. Silver plating is further applied on the nickel plating.
The resist in the small holes is removed by a resist stripper.
The metal film (two layers) is peeled from the stainless steel plate.

In the case of this electrohoming method, the number of steps is increased and the cost is increased. In addition, a metal film cannot be formed too thick with small holes of 5 to 30 μm. In particular, when a thick film having a thickness of 20 to 30 μm or more is formed, it is difficult to control the size of the small holes for the following reason.

FIG. 5 is a cross-sectional view of a main part in a state where silver plating is further performed on nickel plating in the above-described manufacturing method by the electrohoming method. FIG. 6 shows a metal film (two layers) formed by a stayless plate. It is principal part sectional drawing of the state which peeled. FIG.
In the figure, 30 is a stainless steel flat plate, 31 is a resist film, 32 is a release coating, 33 is a nickel plating layer, and 34 is a silver plating layer. If the resist film 31 is made thicker, a stripper side surface that is perpendicular to the straight line cannot be obtained when the resist film 31 is exposed and stripped, and the stripper side surface is inevitably inclined and cannot be finished with accurate dimensions. Since the thickness of the resist film 31 cannot be increased, the thickness t1 of the resist film 31 is usually about 10 to 20.
It is formed in a thickness range of μm. When the metal film 22 is formed below the thickness range, the size of the hole diameter d1 of the small hole 22a can be formed with high accuracy.

However, in order to form a concavo-convex pattern such as a basis pattern or a lattice pattern on the metal film 22, a thickness of the metal layer 22 of at least t2 ≒ 30 μm or more is required.
As shown in FIG. 5, if the plating is formed to be thicker than the thickness t1 of the resist film 31, the thickness t2 of the metal film 22 is large.
The plating is formed on the resist film 31 side so as to protrude, and a plating protruding portion 35 is generated.

Therefore, as shown in FIG.
If the metal film (two layers) 22 is peeled off from the stainless steel plate, a plating protrusion 35 is formed inside the small hole 22a, and the hole diameter d1 of the small hole 22a is reduced accordingly. If the small holes 22a become extremely small, it may appear that the plating protruding portions 35 are connected and the small holes 22a are not formed. In particular, when the small holes 22a are small, it becomes difficult to manage the dimensions. As shown in FIG. 3, in the case of the timepiece display panel 20, since the metal film 22 is provided on the upper surface of the transmissive display substrate 21, the small hole 22a has a large diameter that cannot be visually recognized. Can not do.

[0011] Further, 5-30
When forming a metal film in which a large number of small holes of 20 μm are provided at an area ratio of 20 to 50%, a portion where the resist film is peeled off from the stainless steel plate and plated is formed.
When a small hole having a very small size of μm is formed at an area ratio of 50%, the width of a portion to be plated must be set to 5 μm. When the width of the portion to be plated becomes small, the plating solution does not sufficiently flow and the riding of the plating becomes poor. Therefore,
Inevitably, a phenomenon that the plating thickness becomes thin at that portion appears, and a metal film having a uniform thickness cannot be obtained.

When the above-described metal film is used for a backlight structure of a liquid crystal display panel, the metal film may have a function of transmitting and reflecting light. When used for a timepiece type display panel, an appearance function is also required, and decorativeness by pattern formation is also required. Therefore, a metal film having a predetermined thickness of, for example, 30 μm or more is required.

[0013]

However, when a metal film is formed by the above-described electrohoming method,
It is difficult to control the size of the small holes due to the relationship between the diameter of the small holes formed in the metal film and the thickness of the metal film. In addition, the electrohoming method requires a long manufacturing process and is expensive. An issue is the emergence of a metal film that facilitates dimensional control of small holes and that can reduce manufacturing costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object the purpose of increasing the amount of transmitted external light and the amount of transmitted light from a backlight, having decorativeness as a display panel, and having a metallic appearance and a high-grade appearance. An object of the present invention is to provide a light-transmitting display panel which is simple in manufacturing process, reduced in the number of steps, and inexpensive, and an electronic display device using the same.

[0015]

In order to achieve the above object, the light-transmitting display plate of the present invention has a hole diameter of about 40 to 40.
A metal film in which a large number of small holes having a size of 70 μm are dispersed and arranged at a predetermined interval at an area ratio of approximately 20 to 50% of the surface area is disposed on the lower surface side of the transparent display substrate. is there.

Further, the metal film is characterized in that an uneven pattern is formed on the upper surface side.

Further, a small hole having a hole diameter of about 40 to 70 μm
A large number of metal films having an area ratio of approximately 20 to 50% of the surface area and dispersed at predetermined intervals are arranged on the lower surface side of the liquid crystal cell.

The present invention also relates to an electronic display device provided with a solar cell or a backlight, wherein the hole diameter is approximately 40 to 70 μm on the upper surface side of the solar cell or the backlight.
A metal film in which a large number of small holes having a size of about 20 to 50% of the surface area are dispersed and arranged at predetermined intervals is provided on the lower surface side of the transparent display substrate. In which an uneven pattern is formed.

According to the present invention, there is provided an electronic display device provided with a solar cell or a backlight, wherein the hole diameter is approximately 40 to 70 μm on the upper surface side of the solar cell or the backlight.
A metal film in which a large number of small holes having an area ratio of about 20 to 50% of the surface area are dispersed at predetermined intervals is provided on the lower surface side of the liquid crystal cell.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A light-transmitting display panel according to the present invention will be described below with reference to the drawings. FIG. 1 shows a light transmissive display panel according to the first embodiment of the present invention.
(A) is a sectional view of a main part of a solar cell dial structure, FIG.
(B) is a partial sectional view thereof.

In FIG. 1, the timepiece display panel 1 has small holes 3a having a hole diameter of approximately 40 to 70 μm on the lower surface side of the transmissive display substrate 2 at an area ratio of approximately 20 to 50% of the surface area, and A plurality of metal films 3 are arranged at equal intervals and are configured to transmit light through the small holes 3a. The transparent display substrate 4 and the metal film 3 constitute a light transparent display plate 4.

Metal film 3 constituting light transmissive display plate 4
Has a thickness of 30 μm or more, and has an uneven pattern 3b (see FIG. 1b) such as a basis pattern or a lattice pattern on the upper surface side. Indices 5 such as hour marks and marks are fixed at predetermined positions on the upper surface side of the transmissive display substrate 2. A solar cell 6 for driving a timepiece is provided on the lower surface side of the timepiece display panel 1. Further, instead of the solar cell 6, an EL that emits light when dark may be provided.

The metal film 3 constituting the light transmissive display panel 4
Even if the diameter of the small holes 3a formed in the substrate is 40 to 70 μm, if the small holes are formed at equal intervals and adhered to the lower surface side of the translucent display substrate 2, the small holes 3a are hardly formed. Become invisible. Furthermore, if the transmissive display substrate 2 is colored, it cannot be seen at all. Conventionally, a metal film is provided on the upper surface side of the transmissive display substrate. However, by adopting the structure in which the metal film 3 is provided on the lower surface side of the transmissive display substrate 2 as described above, a hole diameter of approximately 40 to 70 μm is obtained. Even the small holes 3a become invisible.

In the method of manufacturing the metal film 3, when the small holes 3a have a size of approximately 40 to 70 μm, a resist film can be directly formed by screen printing, unlike the conventional electrohoming method. At present, the screen printing method has a screen mesh having a wire diameter of about 10 μm or more.
Printing with a width of about μm becomes possible. From this, 4
When the size is 0 μm or more, it can be formed by direct printing.
Further, since the printed film can be formed thick, even if plating is performed to a predetermined thickness, for example, 30 μm or more (two-layer plating of nickel plating and silver plating), plating does not protrude on the resist side, and the hole diameter of the small hole 3a is small. The size of the hole diameter is easy to control because it is formed with high precision without becoming small. As compared with the conventional electrohoming method, the manufacturing process is simple, the number of processes is short, and the manufacturing cost is low.

When the size of the small hole 3a is approximately 40 to 70 μm, the width of the portion to be plated is at least 40 μm.
m or more, the plating solution can sufficiently flow around during plating, and the riding of plating can be improved, and a metal film having a uniform thickness can be formed.

Since the metal film 3 has at least an upper metal layer, for example, a silver metal layer, an anti-oxidation film (not shown) such as silicon oxide may be formed on the surface thereof.

Further, as described above, the concavo-convex pattern 3b such as a basis pattern or a lattice pattern is formed on the upper surface side of the metal film 3.

According to the above-described structure, the small holes 3a are set to have a hole diameter of about 40 to 70 μm, and a large number of the small holes 3a are arranged at an area ratio of about 20 to 50% of the surface area and are evenly spaced to provide a light transmitting property. Since the light transmissive display panel 4 is formed by disposing the metal film 3 on the lower surface side of the display substrate 2, the small holes 3a are invisible to the naked eye. Since the hole diameter is large, light can be transmitted through the small holes 3a, and external light can pass through the dial to sufficiently satisfy the power generation function of the solar cell. Here, when used for a solar cell, it is preferable to form the holes at equal intervals since the power generation efficiency is increased. Even when the watch is used as a dial of a watch provided with an EL, the EL
The luminescent light is transmitted to sufficiently illuminate the dial, and the dial can be clearly recognized. In addition, in the case of use in EL, if a large number of small holes 3a are provided at equal intervals, the surface of the dial can be uniformly illuminated. Small holes 3a at intervals
Should be provided. With such a configuration, a metal color unique to the metal due to the metal film 3 appears, giving a metallic feeling and a luxurious appearance. Further, by forming the uneven pattern 3b such as a satin pattern, a shining pattern, a striped pattern, etc. on the upper surface side of the metal film 3, the decorativeness of the dial can be enhanced and the decorative variations can be increased.

In this embodiment, a resist film is formed directly on a portion corresponding to a small hole by a screen printing method, a portion without the resist film is plated, and then the resist film is peeled off to form a metal film. Although the method has been described, it can also be formed by a conventional electrohoming method.
Even if it is impossible to make the metal film too thick, if the small holes are large, the wraparound of the plating solution during plating is improved, and a metal film having a uniform film thickness can be formed.

FIG. 2 shows a light-transmitting display panel according to a second embodiment of the present invention, and FIG.
FIG. 2B is a cross-sectional view of a main part of a metal film included in the light transmissive display panel.

In FIG. 2 (a), a liquid crystal cell 10 has a transparent upper display electrode 1 on the inner surface side of a transparent upper glass substrate 11a and a lower glass substrate 11b.
2a and the lower display electrode 12b are formed. Further, an upper alignment film 13a and a lower alignment film 13b are provided thereon, and a liquid crystal substance 16 is injected into the structure while being sealed with a sealing material 15 with spacer balls 14 interposed therebetween. Further, an upper polarizer 17a and a lower polarizer 17b are provided on the upper surface of the upper glass substrate 11a and the lower surface of the lower glass substrate 11b, thereby forming the liquid crystal cell 10. The lower polarizing plate 17 of the liquid crystal cell 10
The metal film 3 described in the first embodiment is bonded and fixed to the lower surface side of b to form the light transmissive display panel 18. Reference numeral 19 denotes an EL as a backlight.

As described above, the metal film 3 has a two-layered metal structure in which the upper layer is a silver metal layer and the lower layer is a nickel metal layer. On the surface of the upper silver metal layer, a light diffusing surface with minute unevenness is formed. The lower nickel metal layer is not limited to nickel metal, but may be any metal having plating properties and good adhesion to silver metal.

As for the metal film 3, at least the upper metal layer is, for example, a silver metal layer, and the surface thereof is formed as shown in FIG.
As shown in FIG. 7, an anti-oxidation film 3c such as silicon oxide may be applied.

Further, by providing a transparent color paint film (not shown) on the upper surface of the silver metal layer constituting the metal film 3, a desired color color is formed on the upper surface of the silver metal layer having many small holes 3a in a bright place. Since the display appears, the color variations can be enriched.

When the metal film 3 is viewed from the upper surface of the liquid crystal cell 10 with the naked eye, the transparent color paint film is provided on the upper surface of the silver metal layer.
a is not visible at all.

Since the reflected light is diffused by forming minute irregularities on the surface of the silver metal layer constituting the metal film 3, the reflected light enters the liquid crystal panel again with a uniform light amount distribution. In addition, there is no uneven brightness in the reflected light, and no uneven brightness in the display occurs.

Further, when the packlight is lit in a dark place, the small holes 3a are relatively large, approximately 40 to 70 μm, and are formed with an area ratio of 20 to 50%, so that the transmittance can be significantly increased. Since the transmitted light can be increased and the small holes 3a are provided at predetermined intervals, interference decreases in the transmitted light, and a portion where the brightness is increased and a portion where the brightness is reduced are generated, which alternately occur. As the bright part of the mixture is strongly irritating to the eyes, the afterimage remains forever,
Conversely, the effect of doubling the brightness works, giving a further sense of brightness.

In the above embodiment, the metal film 3
Although the light diffusion surface having minute irregularities is provided on the surface of the silver metal layer on the surface of the above, the surface of the silver metal layer may be finished to a flat mirror surface. With a mirror surface, it is possible to obtain a silver-tone display with a glossy display color. The appearance of this noble metal color gives a sense of luxury.

In the two embodiments described above,
The metal layer constituting the light transmissive display panel was composed of two layers of nickel metal in the lower layer and silver metal in the upper layer, which was set in consideration of light reflectivity, cost, metal workability, and the like. Things. This metal layer is not limited to this,
Those having high reflectivity, easy workability, and low cost are preferable.

As described above, a solar character plate structure having a light transmissive display plate provided with a metal film on the lower surface side of a transmissive display substrate and a light transmissive display plate provided with a metal film on the lower surface side of a liquid crystal cell are provided. Although the EL backlight structure has been described, the present invention is widely applied to light transmission display plates and electronic display devices using the same in displays of watches, mobile phones, electronic information processing devices and the like.

[0041]

As described above, the light-transmitting display panel of the present invention and the electronic display device using the same can sufficiently transmit light because of the large diameter of the small hole in the solar dial structure such as a timepiece. It is possible to satisfy the solar cell power generation function and the illumination of the dial by EL light emission. Also,
A metal color unique to the metal appears due to the metal layer, giving a metallic appearance and a luxurious appearance. In the case of a color-transmissive display substrate, the color is erased and the small holes are hardly visible. In addition, by providing an uneven pattern on the upper surface of the metal film, it is possible to enhance the decorativeness of the dial and to enrich the decorative variations.

Also, in the EL backlight structure of a liquid crystal cell of an electronic display device or the like, since the external light returns to the viewing side with a high reflectance due to the minute diffusion surface of the silver metal layer on the surface, the display is bright, and uneven brightness occurs. There is no. In addition, the light of the backlight can be transmitted through the small holes to illuminate the liquid crystal display panel, and at the same time, the brightness can be further felt by the interference of light, and the display brightness of the liquid crystal cell can be adjusted. . Since the light transmitting display panel is provided on the lower surface side of the liquid crystal cell, the small holes are not visible at all. Further, by providing a transparent color paint film on the metal layer, a color display can be obtained. It is possible to provide a liquid crystal electronic display device which has a bright display, is clear, has no unevenness of light and dark, has adjustable display brightness, and has excellent display quality.

Further, unlike the conventional troublesome electrohoming method, a thick resist film can be directly formed by a screen printing method, so that the cost can be reduced and the thickness of the metal film can be increased (30 μm or more). In addition, it is possible to apply an uneven pattern such as a basis pattern or a lattice pattern to the metal film.

[Brief description of the drawings]

FIG. 1 relates to a first embodiment of the present invention, and FIG.
It is a principal part sectional view which shows the solar dial structure which has a light transmissive display board which arrange | positioned the metal film on the lower surface side of the transmissive display board.

FIG. 2 relates to a second embodiment of the present invention, which has an optically transparent display panel in which a metal film is disposed on the lower surface side of a liquid crystal cell.
It is principal part sectional drawing which shows an L backlight structure.

FIG. 3 is a cross-sectional view of a main part showing a conventional solar dial structure in which a metal film is disposed on the upper surface side of a transparent display substrate.

FIG. 4 is a plan view of the timepiece dial of FIG. 3;

FIG. 5 is a cross-sectional view of a main part showing a conventional method for manufacturing a metal film.

6 is a cross-sectional view of a main part showing a state where the plating of the metal film of FIG. 5 has protruded.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Watch display panel 2 Transmissive display board 3 Metal film 3a Small hole 3b Concavo-convex pattern 4 Light transmissive display board 5 Indicator 6 Solar cell 10 Liquid crystal cell 18 Light transmissive display board 19 Backlight (EL)

Claims (5)

[Claims] 1. A metal film in which a large number of small holes having a hole diameter of about 40 to 70 μm are dispersed and arranged at a predetermined interval at an area ratio of about 20 to 50% of the surface area, on a lower surface side of a transparent display substrate. A light transmissive display panel, which is provided. 2. The light-transmitting display panel according to claim 1, wherein an uneven pattern is formed on an upper surface of the metal film. 3. A metal film in which a large number of small holes having a hole diameter of about 40 to 70 μm are dispersed and arranged at a predetermined interval at an area ratio of about 20 to 50% of the surface area, and are disposed on the lower surface side of the liquid crystal cell. A light transmissive display plate characterized by the following. 4. An electronic display device comprising a solar cell or a backlight, wherein the light transmissive display panel according to claim 1 or 2 is provided on an upper surface side of the solar cell or the backlight. 5. An electronic display device comprising a solar cell or a backlight, wherein the light transmissive display panel according to claim 3 is provided on an upper surface side of the solar cell or the backlight.