JP2003287580A - Dial for watch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To see a pattern on the lower surface of a transparent substrate. <P>SOLUTION: The transmitting substrate 2 constituting a watch dial 1 has a plurality of recesses and bumps on the lower surface 2a, the recesses 2b are formed in mirror face and have reflection film. The bumps 2c have smooth surface 2d and is transparent. The shape of the smooth surface 2d is a circle with a diameter d of 120 μm or less. A plurality of circles are dispersively arranged to be patterns of regular triangles or regular hexagons. The reflection film 3 consists of metal evaporated film and the like. The vertical cross sectional shape of the bumps 2c is a trapezoid so as to be easy for formation. The total area of the smooth surface 2d of the transparent bumps 2c is 20 to 50% of the area of the transparent substrate 2. The reflection mirror 3 is formed on the bottom surface of the recesses 2b formed on the mirror surface and a taper gradient surface, and so the reflection light is easily dispersed or scattered, dark purple of the solar cell is not seen at all and face having high quality sense owing to the reflection light from the metal reflection film is realized at low cost. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timepiece dial, more specifically to a solar battery timepiece dial or a backlight timepiece dial.

[0002]

2. Description of the Related Art Conventionally, as a dial for timepieces for solar cells, a dial is used as a technique for giving a metallic appearance to the appearance and for preventing the peculiar purplish color of the solar cells arranged on the lower surface from being seen. Various concave and convex patterns, for example, a lattice pattern, a circle pattern, various geometric patterns, and the like are applied. As such a conventional timepiece dial, for example, Japanese Patent Application No. 2000-33507 previously filed by the present applicant.
No. 4, Japanese Patent Application No. 2001-091148, the technique is disclosed.

In the above-mentioned Japanese Patent Application No. 2000-335074, as shown in FIGS. 3 and 4, 10 is a timepiece dial for a solar cell, and 11 is a light which is a main member constituting the timepiece dial 10. A transparent substrate made of a transparent plastic material. The recesses 12 are densely arranged in a matrix on the lower surface thereof. The portion where the concave portion 12 is not formed is relatively convex. On the inner surface of the concave portion 12, a reflection film 14 is formed, which is a non-transmissive portion, that is, a metal vapor deposition film, a paint film, or a laminated film of a metal vapor deposition film and a paint film.

On the upper surface of the timepiece dial 10, indexes such as hour characters and marks (not shown) are formed. Then, the upper surface 13a of the convex portion 13 is polished to expose the transparent substrate 11 and becomes a smooth surface. Then, the total area of the polished upper surface 13a is 20 times the total area of the transparent substrate 11.
It is formed so as to fall within a range of up to 50%.

The height h of the protrusion 13 is at least 10 μm or more, and the width t of the upper surface 13a is 100 μm or less. Such a method of manufacturing the timepiece dial 10 having a concavo-convex pattern is based on an injection molding method or a method of transferring under heat and pressure using a mold having a concavo-convex pattern.

In this timepiece dial 10, a transparent substrate 11 is used.
Since the width t of the transparent part is limited to 100 μm or less, the shape of the transparent part and the dark purple of the solar cell cannot be recognized from above the timepiece dial 10. By selecting the reflective film 14, the light reflected on the lower surface of the timepiece dial 10 gives the dial surface a metallic appearance and a good-looking appearance.

However, the width t of the light transmitting portion is 100 μm.
Since it is set to m or less, it takes a lot of time to manufacture the mold and it is very expensive. This increases the cost of the dial for watches.

Therefore, as a technique for solving this problem,
In Japanese Patent Application No. 2001-091348, as shown in FIG. 5, reference numeral 20 is a dial for a solar cell timepiece arranged on a solar cell, and 21 is a main member constituting the dial 20 for a light. A transparent substrate made of a transparent plastic material, the upper surface 21a of the transparent substrate 21 is flat, and the lower surface 21b has uneven portions formed in a pattern,
The recesses 21c are densely arranged in a matrix. Recess 21c
In addition to this matrix-like pattern, a stripe pattern,
There are circle patterns and other geometric patterns.

The bottom surface of the recess 21c is mirror-finished and has a reflection film 22. The reflective film 22 is a non-transmissive portion made of a metal vapor deposition film formed to have a thickness that does not transmit light. Not limited to the metal vapor deposition film which is the non-transmissive portion, it may be formed of a paint film or a laminated film of a metal vapor deposition film and a paint film.

The lower surface 21b of the transparent substrate 21 has a convex portion 21d having transparency, and the width t of the transparent portion is 120 μm.
It is the following. The total area of the transmissive part is formed to be in the range of 20 to 50% of the total area of the transmissive substrate 21, so that a uniform amount of light can be obtained in the solar cell and sufficient power generation is possible.

As described above, the reason why the bottom surface of the concave portion 21c is mirror-finished is that the portion is well reflected and has a luster, so that it is confused by the luster and the width of the transmissive portion is 120 μm. The size is not visible.

Further, as shown in FIG. 6, by forming the pattern 21e on the upper surface 21a of the transparent substrate 21, the reflected light of the solar cell transmitted from the transparent portion of the lower surface 21b is formed on the upper surface 21a. Light is dispersed and scattered by the patterned pattern 21e thus generated, and is emitted. Due to this dispersion and scattering, the existence of the solar cell is made less noticeable. Moreover, if the pattern on the lower surface is different, the reflected light from the solar cell is dispersed by the unevenness of the pattern on the upper surface side, so that the dark purple color of the solar cell is not visible.

[0013]

However, when the size of the transparent convex portion is 120 μm, a pattern such as a stripe pattern, a circle pattern, or a lattice pattern is emphasized unless a pattern pattern is formed on the upper surface side. Although it is a slight pattern, it is visually recognized. Further, there is a problem that forming the pattern pattern on the upper surface side increases the cost.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to form a solar cell without forming an uneven pattern on the upper surface of a transparent substrate, and to observe the dark purple of the solar cell, thereby facilitating the manufacture. It is intended to provide an inexpensive timepiece dial for a solar cell.

[0015]

In order to achieve the above object, a timepiece dial according to the present invention is a timepiece dial using a transparent substrate, wherein the transparent substrate has a plurality of uneven portions on its lower surface. The concave portion is formed into a mirror surface and has a reflective film, the convex portion is a smooth surface and has transparency, and the shape of the smooth surface of the convex portion is a circle of 120 μm or less, It is characterized in that the plurality of circles are dispersed and arranged in a regular triangular or regular hexagonal pattern shape.

Further, the reflective film is a metal vapor deposition film, a paint film, or a laminated film of a metal vapor deposition film and a paint film.

Further, the vertical cross-sectional shape of the convex portion is a trapezoidal shape.

The total area of the smooth surface of the transparent convex portion is 20 to 50% of the area of the transparent substrate.
It is characterized by being.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION A timepiece dial according to the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of an essential part of a timepiece dial according to an embodiment of the present invention. 2A is a sectional view taken along the line AA of FIG. 1, and FIG. 2B is a partially enlarged sectional view of FIG. 2A.

In FIGS. 1 and 2, 1 is a timepiece dial for a solar cell, and 2 is a transparent substrate made of a light-transmissive plastic material which is a main component of the timepiece dial 1. The transparent substrate 2 has a plurality of concave and convex portions on its lower surface 2a, the concave portion 2b is formed as a mirror surface, and a metal reflection film 3 is formed thereon. The metal reflection film 3 is formed of, for example, a silver (Ag) vapor deposition film and chromium (C).
r) It is composed of a two-layer reflective film made of a vapor deposition film. This Ag
The thickness of the vapor deposition film is about 600 to 1000Å, and the thickness of the Cr vapor deposition film formed to prevent discoloration of the Ag vapor deposition film is
It is about 300 to 500Å.

The reflection film 3 may be a coating film or a laminated film of a metal deposition film and a coating film, in addition to the metal deposition film.

The vertical sectional shape of the convex portion 2c is shown in FIG.
It has a trapezoidal shape as shown in, and a predetermined angle (α),
For example, it has a taper of about 2 to 15 °. Then, the surface of the convex portion 2c having transparency is polished to be a smooth surface 2d. The shape of the smooth surface 2d of the convex portion 2c is, for example, a circle having a diameter d of 120 μm or less and a height h of 50 μm or less, and the plurality of circles are dispersed and arranged so as to have a regular triangular or regular hexagonal pattern shape. ing.

A smooth surface 2d of the transparent convex portion 2c.
The total area of the transparent substrate 2 is 20 to 5 with respect to the area of the transparent substrate 2.
It is 0%, which is sufficient as the amount of light necessary for power generation of the solar cell. The upper surface 2e of the timepiece dial 1 is provided with indicators such as hour characters and marks (not shown).

The operation and effect of the timepiece dial having the above structure will be described. The watch dial 1 with the uneven pattern
Is based on an injection molding method or a method of transferring under heat and pressure using a mold having an uneven pattern. The height h of the convex portion 2c is at least 50 μm or less (10 μm or more), and the circular diameter d of the smooth surface 2d is 120 μm.
Since it is the following and has a taper (α) of about 2 to 15 °, the transparent substrate 2 can be easily molded and can be manufactured at low cost. Further, by disposing a plurality of circles, which are smooth surfaces 2d having transparency, in a dispersed manner so as to form a regular triangular or regular hexagonal aggregate pattern, it is difficult to recognize as a pattern, and further, the concave portion 2b is formed on a mirror surface. Since that portion has good gloss by reflecting light, the gloss of 120 μm (diameter d of the smooth surface circle) is not visually recognized. (In addition, the pattern of circles, circles, etc. where circles are arranged is easy to be seen by the human eye. Squares, circles, etc. have directionality.
It is presumed that this is because the pattern is easily visually recognized. From this, it is considered that it becomes difficult for the human eye to visually recognize as a pattern by forming the round dots into a regular triangular or regular hexagonal pattern. ) Furthermore, since the reflection film 3 is formed on the bottom surface of the concave portion 2b and the tapered slope, the reflected light is easily dispersed and scattered,
The dark purple color of the solar cell is not visible at all. Furthermore, the reflected light from the metal reflection film can give the dial a high-class appearance.

By thinly coloring the transparent substrate made of the above-mentioned light-transmissive plastic material, it is possible to enhance the appearance and at the same time make the dark purple color of the solar cell more difficult to see.

Here, a method for manufacturing the above-mentioned timepiece dial will be briefly described. First, a dial blank made of a transparent plastic substrate is formed. In this case, the convex portion of the die corresponding to the bottom surface of the concave portion of the dial is mirror-finished in advance. Then, a blank is formed by injection molding. Alternatively, there is a method of forming the uneven portion by press molding. In this step, the uneven portion is formed by transferring the uneven portion formed by the mold to the blank. Next, a reflective film is formed on the entire surface of the blank having the uneven portion. In the case of vapor deposition of metal, this is formed to a thickness (approximately 1000 Å) that does not allow light to pass through. In the coating method, the reflective film may be formed by applying a coating film to a thickness that does not allow light to pass through. next,
The upper surface of the convex portion is polished until the transparent substrate is exposed, and the reflective film on the convex portion is removed to form a smooth surface.

Although the timepiece dial for a solar cell has been described above, the present invention is similarly applied to a timepiece dial with a backlight in which a backlight such as electroluminescence is arranged on the lower surface side of the dial. it can. Since the light transmissive portion cannot be seen at all, the electroluminescence disposed therebelow cannot be seen at all, and the light transmissive portion can be enlarged. Therefore, a large amount of light can be extracted and brighter illumination can be achieved.

[0028]

As described above, according to the present invention,
Arranging multiple circles, which are smooth and transparent surfaces, so as to form a set pattern of regular triangles or regular hexagons. In addition, the transmissive part has a pattern due to the synergistic effect of reflecting the light well because the concave part is formed as a mirror surface and further dispersing and scattering the reflected light from the reflective film formed on the bottom surface of the concave part and especially on the inclined surface. It is difficult to recognize as, and the dark purple color of the solar cell is not visible. Further, since the shape of the convex portion is a trapezoidal shape, the molding process becomes easier. Furthermore, the metallic reflection film gives a high-grade appearance. Moreover, a sufficient amount of power generation can be obtained by the light transmitting portion. It is possible to provide a new inexpensive dial plate for a solar watch or a watch with a backlight.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of a timepiece dial according to an embodiment of the invention.

2A is a sectional view taken along line AA of FIG.
2B is a partially enlarged sectional view of FIG.

FIG. 3 is a sectional view of an essential part of a conventional timepiece dial.

FIG. 4 is a perspective view of a main part of the timepiece dial shown in FIG.

FIG. 5 is a sectional view of an essential part of another conventional timepiece dial.

FIG. 6 is a cross-sectional view of a main part of still another conventional timepiece dial.

[Explanation of symbols]

1 Clock face 2 Transparent substrate 2a lower surface 2b recess 2c convex part 2d smooth surface 2e Upper surface 3 reflective film d Diameter of smooth surface circle h Height of convex part α slope angle

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhiko Takayama             2 6663 Funatsu, Kawaguchiko Town, Minamitsuru District, Yamanashi Prefecture               Kawaguchiko Precision Co., Ltd. (72) Inventor Katsuyuki Yamaguchi             6-12 Tanashi-cho, Nishi-Tokyo, Tokyo             Chisun Watch Co., Ltd.

Claims (4)

[Claims] 1. A timepiece dial using a transmissive substrate, wherein the transmissive substrate has a plurality of concave and convex portions on a lower surface thereof, and the concave portion is formed as a mirror surface and has a reflective film, The convex portion is a smooth surface and is transparent, and the shape of the smooth surface of the convex portion is a circle of 120 μm or less, and the plurality of circles are dispersed and arranged so as to have a regular triangular or regular hexagonal pattern shape. A dial for watches that is characterized by that. 2. The timepiece dial according to claim 1, wherein the reflective film is a metal vapor deposition film, a paint film, or a laminated film of a metal vapor deposition film and a paint film. 3. The timepiece dial according to claim 1, wherein the vertical cross-sectional shape of the convex portion is trapezoidal. 4. The timepiece according to claim 1, 2 or 3, wherein the total area of the smooth surface of the transparent convex portion is 20 to 50% of the area of the transparent substrate. Dial.