JP4992607B2 - Clock dial and clock - Google Patents

Description

  The present invention relates to a timepiece dial and a timepiece.

A timepiece dial is required to have excellent aesthetic appearance as a decorative product as well as excellent visibility as a practical product. Conventionally, in order to achieve such an object, a metal material such as Au or Ag has generally been used as a constituent material of a timepiece dial.
Also, on the other hand, for the purpose of reducing production costs and improving the degree of freedom in forming the timepiece dial, an attempt is made to form a coating made of a metal material on the surface using plastic as a base material. (For example, refer to Patent Document 1).
However, plastics generally have poor adhesion to metal materials. For this reason, there is a problem that peeling between the base material and the coating film is likely to occur, and the durability of the timepiece dial is inferior.

  Further, for example, in a solar timepiece having a solar cell, the timepiece dial is required to have light (visible light) transparency. For this reason, plastic dials have been used as such timepiece dials. However, since plastic lacks a high-class feeling, it is made of a metal material for the purpose of improving the aesthetic appearance of the timepiece dial. There is an attempt to coat with a thin film. However, as described above, there is a problem that plastic is inferior in adhesion to a metal material. Moreover, in order to improve the light transmittance, it is necessary to make the thickness of the thin film sufficiently thin. However, in such a case, there is a problem that the aesthetic appearance of the timepiece dial as a whole is lowered.

JP 2003-239083 A (page 4, left column, lines 37-42)

  An object of the present invention is to provide a timepiece dial that is excellent in light (visible light) transmission and has an aesthetic appearance and durability, and to provide a timepiece having the timepiece dial. In particular, an object of the present invention is to provide a watch that is excellent in the power generation efficiency of a solar cell and can stably exhibit an excellent aesthetic appearance.

Such an object is achieved by the present invention described below.
The timepiece dial of the present invention is a timepiece dial used in a solar timepiece equipped with a solar cell,
A substrate composed primarily of polycarbonate;
A zinc sulfide layer provided on the first surface side, which is one main surface of the base material, and mainly composed of ZnS ;
A silicon oxide layer provided between the base material and the zinc sulfide layer and mainly composed of SiO ₂ ;
Wherein the said surface facing the silicon oxide layer of a zinc sulfide layer provided on the opposite side of, is made of a material containing a coloring agent and / or a diffusing agent, it possesses a coating film having optical transparency ,
An indicator is provided on the second surface side, which is the main surface opposite to the first surface of the base material,
The timepiece dial is used such that the second surface, which is the main surface opposite to the first surface of the base material, faces the outer surface side (observer side),
The silicon oxide layer has a thickness of 20 to 200 nm;
The zinc sulfide layer has a thickness of 10 to 100 nm,
The total thickness of the silicon oxide layer and the zinc sulfide layer is 50 to 250 nm .
As a result, it is possible to provide a timepiece dial having excellent light (visible light) transparency and an excellent aesthetic appearance and durability. In addition, the visibility of the index can be improved.

In the timepiece dial of the present invention, the coating film has a structure in which mica (mica) is coated with TiO ₂ and is made of a material containing powder having an average particle diameter of 1 to 30 μm. It is preferable.
Thereby, the aesthetic appearance of the timepiece dial can be further improved while the light transmittance is sufficiently high.

In the timepiece dial of the present invention, the color tone of the second surface side, which is the main surface opposite to the first surface of the base material of the timepiece dial, is defined by JIS Z 8729. in the chromaticity diagram of the L ^* a ^* b ^* display, ^{a *} is -8～8, and, ^{b *} is preferably a -8～8.
Thereby, the aesthetic appearance of the timepiece dial is particularly excellent.

The timepiece of the present invention is a timepiece including a solar cell and a cover glass disposed on the outer surface side of the solar cell,
Between the solar cell and the cover glass, equipped with a timepiece dial of the present invention,
The timepiece dial is arranged such that a second surface, which is a main surface opposite to the first surface of the base material, faces the cover glass side.
Thereby, while being excellent in the power generation efficiency of a solar cell, the timepiece which can exhibit the outstanding aesthetic appearance stably can be provided.

  According to the present invention, it is possible to provide a timepiece dial that is excellent in light (visible light) transparency, aesthetic appearance and durability, and to provide a timepiece including the timepiece dial. In particular, it is possible to provide a timepiece that is excellent in power generation efficiency of a solar cell and can stably exhibit an excellent aesthetic appearance.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings.
First, a preferred embodiment of the timepiece dial of the present invention will be described.
<Watch dial>
FIG. 1 is a cross-sectional view showing a preferred embodiment of the timepiece dial of the present invention.
As shown in FIG. 1, the timepiece dial 1 of this embodiment is in contact with a base material (substrate) 2 mainly composed of polycarbonate and a first surface 21 which is one main surface of the base material 2. Provided on the opposite surface of the silicon oxide layer 3 to the surface in contact with the substrate 2 and mainly composed of zinc sulfide. The zinc sulfide layer 4 and the coating film 5 provided on the surface of the zinc sulfide layer 4 opposite to the surface in contact with the silicon oxide layer 3 and made of a material containing a colorant and / or a diffusing agent. And have. That is, the timepiece dial 1 is provided with a base 2 made mainly of polycarbonate and a first surface 21 which is one main face of the base 2 and is made of zinc sulfide mainly made of zinc sulfide. The material layer 4 is provided between the base material 2 and the zinc sulfide layer 4 and is opposed to the silicon oxide layer 3 mainly composed of silicon oxide and the silicon oxide layer 3 of the zinc sulfide layer 4. It has a coating film 5 that is provided on the surface opposite to the surface, is made of a material containing a colorant and / or a diffusing agent, and has light transmittance. In the present invention, “mainly” means a component having the largest content among materials constituting the target portion, and the content is not particularly limited, but 60 wt% of the material constituting the target portion. % Or more, preferably 80 wt% or more, more preferably 90 wt% or more. Further, in the present invention, “having light transparency” means having a property of transmitting at least part of light in the visible light region (wavelength region of 380 to 780 nm), preferably light in the visible light region. The transmittance of light in the visible light region is more than 25%. For such light transmittance, for example, a value measured using a white fluorescent lamp (manufactured by Hitachi Lighting Co., Ltd., High White (FL15N-B)) as a light source can be employed.

The timepiece dial 1 is usually a second main surface opposite to the first surface 21 of the substrate 2 (that is, the surface covered with the silicon oxide layer 3 and the zinc sulfide layer 4). The surface 22 side (upper side in the figure) is used so as to face the observer side (outer surface side).
As described above, the timepiece dial 1 has the base material 2, the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5, but the polycarbonate constituting the base material 2, The silicon oxide constituting the silicon oxide layer 3, the zinc sulfide constituting the zinc sulfide layer 4, and the coating film 5 are all excellent in light (visible light) transmittance. For this reason, the timepiece dial 1 as a whole is also excellent in light (visible light) transparency. Moreover, by having a structure in which the base material 2, the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5 are laminated in order from the outer surface side, the light (visible light) transmittance is sufficiently excellent. In addition, the aesthetic appearance of the timepiece dial 1 can be made excellent.

[Base material]
The base material 2 is mainly composed of polycarbonate (PC). In the present invention, one of the requirements for the substrate 2 is light transmission. Among various plastic materials, polycarbonate is particularly high in transparency and has excellent light transmittance, so that the light transmittance of the substrate 2 can be made particularly excellent. Furthermore, incident light is suitably reflected and refracted at the interface between the substrate 2 and the silicon oxide layer 3 due to the difference in refractive index between the substrate 2 made of polycarbonate and the silicon oxide layer 3 described later. Thereby, the aesthetic appearance of the timepiece dial 1 can be made particularly excellent. Polycarbonate has a characteristic that it is not easily deformed by an external stress such as light or heat. For this reason, the adhesiveness of the base material 2 made of polycarbonate and the silicon oxide layer 3 described later can be made particularly excellent, and as a result, the durability of the timepiece dial 1 is particularly excellent. It can be. Moreover, when the base material 2 is made of a material containing polycarbonate, the strength of the timepiece dial 1 as a whole can be made particularly excellent. In addition, when the timepiece dial 1 is manufactured, since the degree of freedom in forming the base material 2 is increased (easiness of forming is improved), even if the timepiece dial 1 has a more complicated shape, It can be manufactured easily and reliably. Polycarbonate is relatively inexpensive among various plastic materials, and can contribute to a reduction in production cost of the timepiece dial 1. Further, since polycarbonate is excellent in radio wave permeability, the timepiece dial 1 can be suitably applied to a radio timepiece dial.

  In addition, the base material 2 may contain components other than the said polycarbonate. Examples of such components include plasticizers, antioxidants, colorants (including various color formers, fluorescent substances, phosphorescent substances, etc.), brighteners, fillers, and the like. For example, when the base material 2 is made of a material containing a colorant, variations in the color of the timepiece dial 1 can be widened.

Although the refractive index of the base material 2 mainly composed of polycarbonate is not particularly limited, it is preferably 1.55 to 1.60, and more preferably 1.58 to 1.59. Thereby, light can be more suitably reflected and refracted at the interface between the substrate 2 and the silicon oxide layer 3. As a result, the aesthetic appearance of the timepiece dial 1 can be further improved. In the present specification, “refractive index” refers to an absolute refractive index at room temperature (20 ° C.) unless otherwise specified.
Further, the shape and size of the base material 2 are not particularly limited, and are determined based on the shape and size of the timepiece dial 1 to be manufactured, but usually have a plate shape. In the illustrated configuration, the base material (substrate) 2 has a flat plate shape, but may have a curved plate shape, for example.

Although the thickness of the base material 2 is not specifically limited, It is preferable that it is 150-700 micrometers, It is more preferable that it is 200-600 micrometers, It is more preferable that it is 300-500 micrometers. When the thickness of the base material 2 is a value within the above range, the mechanical strength of the timepiece dial 1 is effectively prevented while the timepiece to which the timepiece dial 1 is applied is effectively prevented from being thickened. The shape stability and the like can be made sufficiently excellent. Further, generally, as the thickness of the base material 2 increases, the light transmission and aesthetic appearance of the timepiece dial 1 become worse. However, since polycarbonate has a low refractive index, if the thickness of the base material 2 is within the above range, there is no difference in light transmission and aesthetic appearance depending on the thickness of the base material 2. While making the aesthetic appearance of the board 1 sufficiently excellent, the light transmittance can be made particularly excellent.
The substrate 2 may be formed by any method, and examples of the method for forming the substrate 2 include compression molding, extrusion molding, and injection molding.

[Silicon oxide layer]
The first surface 21 of the substrate 2 is provided with a silicon oxide layer 3 mainly composed of silicon oxide.
Since silicon oxide has excellent light transmittance among various metal oxides, the light transmittance of the timepiece dial 1 using the silicon oxide layer 3 is particularly excellent. be able to. Further, the refractive index of the silicon oxide layer 3 is lower than that of the base material 2 made of a material containing polycarbonate, and the difference in refractive index between the silicon oxide layer 3 and the base material 2 made of polycarbonate makes silicon Incident light is suitably reflected and refracted at the interface between the oxide layer 3 and the substrate 2. Similarly, the refractive index of the silicon oxide layer 3 is lower than that of the zinc sulfide layer 4 described in detail later, and incident light is suitably reflected and refracted at the interface between the silicon oxide layer 3 and the zinc sulfide layer 4. . Thereby, the aesthetic appearance of the timepiece dial 1 can be made excellent. In addition, since silicon oxide has a high affinity with polycarbonate and zinc sulfide and has a characteristic that it is not easily deformed by external stress such as light and heat, the silicon oxide layer 3 is made of polycarbonate. The adhesion between the substrate 2 and the zinc sulfide layer 4 is excellent. As a result, the durability of the timepiece dial 1 can be improved. Further, silicon oxide is excellent in affinity with polycarbonate, while zinc sulfide described in detail later has low affinity with polycarbonate. For this reason, the timepiece dial 1 has a configuration in which the silicon oxide layer 3 is provided between the base material 2 and the zinc sulfide layer 4 described in detail later, so that the zinc sulfide is formed on the surface of the base material. Compared to a watch dial coated with a layer, it has superior durability. Furthermore, even if the silicon oxide layer 3 is thick, cracks in the silicon oxide layer 3 and peeling failure at the interface between the base material 2 and the silicon oxide layer 3 are unlikely to occur, and the light transmittance is excellent. However, the aesthetic appearance and durability of the timepiece dial 1 can be made excellent. Further, since silicon oxide is excellent in radio wave permeability, the timepiece dial 1 can be suitably applied to a radio timepiece dial.

The refractive index of the silicon oxide layer 3 is not particularly limited, but is preferably 1.20 to 1.60, and more preferably 1.40 to 1.50. As a result, light can be more suitably reflected and refracted at the interface between the base 2 of the silicon oxide layer 3 and the zinc sulfide layer 4, and the aesthetic appearance of the timepiece dial 1 is particularly excellent. can do.
Further, when the refractive index of the silicon oxide layer 3 is n ₃ and the refractive index of the substrate 2 made of polycarbonate is n ₂ , n is a difference in refractive index between the silicon oxide layer 3 and the substrate 2. the value of ₂ -n ₃ is preferably from 0.05 to 0.30, and more preferably 0.07 to 0.20. Thereby, incident light is suitably reflected and refracted at the interface between the silicon oxide layer 3 and the base material 2, and the aesthetic appearance of the timepiece dial 1 can be made particularly excellent.

Examples of the silicon oxide constituting the silicon oxide layer 3 include SiO and SiO _2. Among them, SiO ₂ is mainly preferable. As a result, light can be more favorably reflected and refracted at the interface between the base 2 of the silicon oxide layer 3 and the zinc sulfide layer 4 while making the light transmission more excellent. The aesthetic appearance of the dial 1 can be made particularly excellent.

  Although the thickness of the silicon oxide layer 3 is not specifically limited, It is preferable that it is 20-200 nm, It is more preferable that it is 30-150 nm, It is further more preferable that it is 50-100 nm. When the thickness of the silicon oxide layer 3 is within the above range, the aesthetic appearance of the timepiece dial 1 can be further improved while the light transmittance is sufficiently high. On the other hand, if the thickness of the silicon oxide layer 3 is less than the lower limit, depending on the thickness of the zinc sulfide layer 4 and the like, it becomes difficult to sufficiently reflect and refract light, and an excellent aesthetic appearance. Can be difficult to obtain. On the other hand, when the thickness of the silicon oxide layer 3 exceeds the upper limit, the light transmission of the timepiece dial 1 may not be sufficiently obtained. Furthermore, when the thickness of the silicon oxide layer 3 exceeds the upper limit, external stress (heat, light) is applied to the timepiece dial 1 due to the difference in shrinkage between the silicon oxide layer 3 and the base material 2. There is a possibility that appearance defects such as cracks in the silicon oxide layer 3 due to the occurrence of the above and defects in peeling at the interface between the silicon oxide layer 3 and the zinc sulfide layer 4 may occur.

[Zinc sulfide layer]
A zinc sulfide layer 4 mainly composed of zinc sulfide is provided on the surface of the silicon oxide layer 3 opposite to the surface in contact with the substrate 2.
The zinc sulfide constituting the zinc sulfide layer 4 is a compound of Zn and S. Since this zinc sulfide is generally a colorless and transparent material and has excellent light transmittance, the light transmittance of the timepiece dial 1 using the zinc sulfide layer 4 is particularly excellent. Can be. Moreover, the refractive index of the zinc sulfide layer 4 is higher than that of the silicon oxide layer 3, and the zinc sulfide layer 4 and the silicon oxide layer are different due to the difference in refractive index between the zinc sulfide layer 4 and the silicon oxide layer 3. The incident light is preferably reflected and refracted at the interface with the head 3. Thereby, the aesthetic appearance of the timepiece dial 1 can be made excellent. In addition, since zinc sulfide has a high affinity with silicon oxide and has a characteristic that it is not easily deformed by external stress such as light or heat, the zinc sulfide layer 4 is formed with the silicon oxide layer 3. Excellent adhesion. As a result, the durability of the timepiece dial 1 can be improved. Further, since zinc sulfide is excellent in radio wave permeability, the timepiece dial 1 can be suitably applied to a radio timepiece dial.

Although the refractive index of the zinc sulfide layer 4 is not particularly limited, it is preferably 2.20 to 2.60, and more preferably 2.30 to 2.35. Thereby, light can be more suitably reflected and refracted at the interface between the zinc sulfide layer 4 and the silicon oxide layer 3, and the aesthetic appearance of the timepiece dial 1 can be made particularly excellent. .
Further, when the refractive index of the zinc sulfide layer 4 was n _4, the value of n ₄ -n ₃ is a difference in refractive index between the zinc sulfide layer 4 and the silicon oxide layer 3 is 0.60 to 1 .40 is preferable, and 0.80 to 1.20 is more preferable. Thereby, incident light can be suitably reflected and refracted at the interface between the zinc sulfide layer 4 and the silicon oxide layer 3, and the aesthetic appearance of the timepiece dial 1 can be made particularly excellent.

Further, the value of n ₂ −n ₃ , which is the difference in refractive index between the substrate 2 and the silicon oxide layer 3, and the difference in refractive index between the zinc sulfide layer 4 and the silicon oxide layer 3, n ₄ −n. ₃ values, both satisfy the above conditions, and the value of _n 4 -n ₂ is the difference in refractive index between the zinc sulfide layer 4 and the substrate 2, that is 0.5 to 1.4 Preferably, it is 0.6-1.2. Thereby, incident light is suitably reflected and refracted at the interface between adjacent layers of the base material 2, the silicon oxide layer 3, and the zinc sulfide layer 4, and the aesthetic appearance of the timepiece dial 1 is particularly excellent. It can be.

  The thickness of the zinc sulfide layer 4 is not particularly limited, but is preferably 10 to 100 nm, more preferably 15 to 80 nm, and still more preferably 20 to 50 nm. When the thickness of the zinc sulfide layer 4 is within the above range, the aesthetic appearance of the timepiece dial 1 can be further improved while the light transmittance is sufficiently high. On the other hand, when the thickness of the zinc sulfide layer 4 is less than the lower limit value, depending on the thickness of the silicon oxide layer 3 or the like, it becomes difficult to sufficiently reflect and refract light, and an excellent aesthetic appearance. Can be difficult to obtain. On the other hand, if the thickness of the zinc sulfide layer 4 exceeds the upper limit, the light transmission of the timepiece dial 1 may not be sufficiently obtained. Further, when the thickness of the zinc sulfide layer 4 exceeds the upper limit, cracks in the zinc sulfide layer 4 due to external stress (heat, light) being applied to the timepiece dial 1, or the zinc sulfide layer 4 There is a possibility that poor appearance such as peeling failure occurs at the interface between the silicon oxide layer 3 and the silicon oxide layer 3.

  The total thickness of the silicon oxide layer 3 and the zinc sulfide layer 4 is not particularly limited, but is preferably 50 to 250 nm, more preferably 80 to 220 nm, and 100 to 200 nm. Further preferred. When the combined thickness of the silicon oxide layer 3 and the zinc sulfide layer 4 is within the above range, the aesthetic appearance of the timepiece dial 1 is further improved while the light transmittance is sufficiently high. Can be

[Coating]
A surface of the zinc sulfide layer 4 opposite to the surface in contact with the silicon oxide layer 3 is made of a material containing a colorant and / or a diffusing agent and has a light-transmitting coating film 5. Yes.
By having the coating film 5 in such a part, the reflected light as the timepiece dial 1 can be colored in a predetermined color or diffused more efficiently. As a result, the aesthetic appearance of the timepiece dial 1 can be made extremely excellent. This is considered to be due to the following reasons. That is, at the interface between the substrate 2 and the silicon oxide layer 3 as described above, the interface between the silicon oxide layer 3 and the zinc sulfide layer 4, the interface between the atmosphere (usually air) and the substrate 2, and the like. A part of the light is reflected and colored and diffused by the coating film 5 so that they act synergistically to obtain a very excellent aesthetic appearance. On the other hand, when the coating film 5 is provided in parts other than the above, the outstanding effect as mentioned above is not acquired. That is, when the coating film 5 is provided on the outer surface side (observer side) of the zinc sulfide layer 4, the light is reflected or refracted at the interface between the silicon oxide layer 3 and the zinc sulfide layer 4. However, the effect of improving the aesthetic appearance due to light reflection and refraction as described above cannot be obtained sufficiently.

  The coating film 5 is composed of a material containing a colorant and / or a diffusing agent, and may be any material as long as it has optical transparency. However, the coating film 5 is composed of a material containing a urethane resin. Preferably there is. Thereby, the adhesiveness of the zinc sulfide layer 4 and the coating film 5 can be made particularly excellent, and the durability of the timepiece dial 1 can be made particularly excellent. Further, when the coating film 5 is made of a material containing a urethane resin, the refractive index of the zinc sulfide and the urethane resin are colored together with the coloring of the incident light by the colorant and / or the diffusion of the incident light by the diffusing agent. Due to the difference from the refractive index, light can be suitably reflected and refracted, and the aesthetic appearance of the timepiece dial 1 can be further improved.

  As a coloring agent which comprises the coating film 5, various pigments and various dyes can be used, for example. Among these, since the pigment is superior in light resistance and the like as compared with the dye, the durability of the timepiece dial 1 can be particularly improved. The pigment is generally insoluble and is present in the form of fine particles in the coating film. For this reason, light can be effectively reflected and scattered in the vicinity of the surface of the pigment particles, and the aesthetic appearance of the timepiece dial 1 can be further improved.

The diffusing agent constituting the coating film 5 may have any shape such as granular (powdered), scale-like, or needle-like, or may be indefinite.
Examples of the constituent material of the diffusing agent include silica, glass, and resin.
As described above, the coating film 5 may contain any colorant and / or any diffusing agent, but preferably includes a powder obtained by coating mica (mica) with TiO ₂ as the diffusing agent. . Thereby, the aesthetic appearance of the timepiece dial 1 can be further improved while the light transmittance is sufficiently high.

When the coating film 5 contains mica (mica) coated with TiO ₂ powder (hereinafter also simply referred to as “powder”), the average particle size of the powder is preferably 1 to 30 μm, More preferably, it is 28 micrometers, and it is still more preferable that it is 10-26 micrometers. When the average particle diameter of the powder is within the above range, the aesthetic appearance of the timepiece dial 1 can be further improved while the light transmittance is sufficiently high.

  When the coating film 5 is composed of the material containing the powder, the content ratio of the powder in the coating film 5 is not particularly limited, but is preferably 5 to 60 wt%, and 10 to 50 wt%. More preferably. When the content of the powder in the coating film 5 is within the above range, the aesthetic appearance of the timepiece dial 1 can be further improved while the light transmittance is sufficiently high.

Moreover, the coating film 5 may have a plurality of regions having different compositions. For example, the coating film 5 may be a laminated body having a plurality of layers having different compositions in the thickness direction, and is composed of a gradient material in which the composition changes in a gradient along the thickness direction. It may be.
Although it is not limited to the thickness of the coating film 5, it is preferable that it is 2-50 micrometers, it is more preferable that it is 6-35 micrometers, and it is further more preferable that it is 12-30 micrometers. When the thickness of the coating film 5 is within the above range, the aesthetic appearance of the timepiece dial 1 can be further improved while the light transmittance is sufficiently high. In addition, the timepiece to which the timepiece dial 1 is applied effectively prevents the thickness of the timepiece from being increased in thickness, and sufficiently improves the mechanical strength, shape stability, and the like of the timepiece dial 1. be able to.

[Indicator member]
The timepiece dial 1 includes an index member 6. Examples of such an index member 6 include letters and numbers (so-called time letters and the like), scales, symbols, various marks, and the like having a function of indicating time and the like. The indicator member 6 is provided so that an indicator portion 61 that functions as an indicator is arranged on the outer surface side of the timepiece dial 1 (the second surface 22 side of the base material 2, the upper side in the drawing). As described above, the timepiece dial 1 includes the substrate 2, the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5 arranged (laminated) in this order. The visibility of (index part 61) is excellent. As a result, the aesthetic appearance (luxury feeling) of the timepiece dial plate 1 as a whole can be made particularly excellent, and the user can easily and accurately recognize the time and the like. That is, the aesthetic appearance as a decorative product and the practicality as a practical product can be compatible at a high level.

In the present embodiment, the timepiece dial 1 has an opening in the dial main body 10 constituted by the base member 2, the silicon oxide layer 3, the zinc sulfide layer 4 and the coating film 5. 101 is provided, and a leg 62 included in the index member 6 is inserted into the opening 101.
By the way, in the past, when fixing the index member having the foot to the dial body, particularly when fixing the index member to the dial body made of a highly transparent material, the foot of the index member is There is a problem that the aesthetic appearance of the timepiece dial as a whole is deteriorated by the user. On the other hand, in the timepiece dial of the present invention, since the base material, the silicon oxide layer, the zinc sulfide layer, and the coating film are arranged in this order, the visibility of the indicator portion is sufficiently excellent. However, it is possible to make it difficult for the user or the like to visually recognize the foot. As a result, the aesthetic appearance of the timepiece dial can be made extremely excellent.
The indicator member 6 may be made of any material, but the material near the surface (near the outer surface of the indicator portion 61) contains various metal materials and various pigments (for example, carbon black). It is preferable that it is comprised by these.

  As described above, in the present invention, the timepiece dial has a aesthetic appearance and a base material mainly composed of polycarbonate, a silicon oxide layer, a zinc sulfide layer, and a coating film. It has excellent durability and light transmission. On the other hand, the excellent effects as described above cannot be obtained unless the configuration of the present invention is provided. That is, if at least one of the substrate, the silicon oxide layer, the zinc sulfide layer, and the coating film is absent, a sufficiently excellent aesthetic appearance cannot be obtained. Further, when the silicon oxide layer is not provided and the zinc sulfide layer is provided on the surface of the base material, the durability of the timepiece dial is very poor. In addition to the base material made of polycarbonate, even if a silicon oxide layer, a zinc sulfide layer, and a coating film are provided, it is sufficient even when the arrangement of each component is not as described above. An excellent aesthetic appearance cannot be obtained.

In the timepiece dial 1 as described above, the color tone of the second face 22 side, that is, the color tone of the upper face in the drawing of the timepiece dial 1 is L ^* a ^* b ^* defined by JIS Z 8729 ^. In the chromaticity diagram of the display, a ^* is preferably −8 to 8, and b ^* is preferably −8 to 8, a ^* is −4 to 4, and b ^* is −4 to 4 is more preferable. Thereby, the aesthetic appearance of the timepiece dial 1 is particularly excellent.

The timepiece dial 1 has a color tone on the second surface 22 side, that is, a color tone on the upper surface in the drawing of the timepiece dial 1 is represented by an L ^* a ^* b ^* display defined by JIS Z 8729. In the chromaticity diagram, L ^* is preferably 55 or more, more preferably L ^* is 75 to 90. As a result, the aesthetic appearance of the timepiece dial 1 has a high degree of whiteness and a higher-grade appearance.

  The thickness of the timepiece dial 1 is not particularly limited, but is preferably 150 to 700 μm, more preferably 200 to 600 μm, and even more preferably 300 to 500 μm. When the thickness of the timepiece dial 1 is within the above range, the timepiece dial 1 is effectively prevented from becoming thicker while the timepiece to which the timepiece dial 1 is applied is prevented from being machined. The mechanical strength, the stability of the shape, etc. can be made sufficiently excellent.

  Further, as described above, the timepiece dial 1 has the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5 in this order on the first surface 21 of the base material 2. Therefore, the variation in the reflectance at each wavelength in the visible light region (wavelength region of 380 to 780 nm) for the entire timepiece dial plate 1 can be made sufficiently small. Thus, when the variation in reflectance at each wavelength in the visible light region is sufficiently small, an excellent aesthetic appearance that is high in whiteness and full of luxury can be obtained. In other words, in the visible light region (wavelength region of 380 to 780 nm), the reflectance A [%] at the wavelength where the reflectance is maximum and the reflectance B [%] at the wavelength where the reflectance is minimum. When the difference A−B is sufficiently small, the above effect can be obtained. Thus, the value of AB is preferably sufficiently small, but more specifically, it is preferably less than 20%, more preferably less than 12%, and less than 7%. More preferably. As a result, the above-described effects are exhibited more significantly.

As described above, the timepiece dial 1 is excellent in aesthetic appearance and light transmittance. For this reason, the timepiece dial 1 can be suitably applied to a solar timepiece (a timepiece incorporating a solar cell) or the like.
The timepiece dial 1 is also excellent in radio wave transmission. For this reason, the timepiece dial 1 can be suitably applied to a radio timepiece (including a solar radio timepiece having a solar cell) and the like.
Moreover, since the timepiece dial 1 is excellent in durability, it can be suitably applied to a portable timepiece (for example, a wristwatch).

<Manufacturing method of timepiece dial>
Next, the manufacturing method of the timepiece dial 1 described above will be described.
FIG. 2 is a cross-sectional view showing a preferred embodiment of the timepiece dial manufacturing method of the present invention.
As shown in FIG. 2, the manufacturing method of the present embodiment includes a base material preparation step (1 a) for preparing the base material 2, and silicon oxide for forming the silicon oxide layer 3 on the first surface 21 of the base material 2. A material layer forming step (1b), a zinc sulfide layer forming step (1c) for forming a zinc sulfide layer 4 on the silicon oxide layer 3, a coating film 5 being formed on the zinc sulfide layer 4, A coating film forming step (1d) for obtaining the plate main body 10, an opening forming step (1e) for forming the opening 101 at a predetermined part of the dial main body 10, and the dial main body 10 provided with the opening 101. And an index member attaching step (1f) for fixing the index member 6.

[Base material preparation process]
First, a base material 2 composed mainly of polycarbonate and having a predetermined thickness and shape is prepared (1a).
As the substrate 2, those described above can be used.
The surface of the substrate 2 may be subjected to surface processing such as mirror surface processing, streak processing, and satin processing. Thereby, it becomes possible to give a variation in the glossiness of the surface of the obtained timepiece dial 1, and the aesthetic appearance of the timepiece dial 1 can be further improved. Moreover, the timepiece dial 1 manufactured using the base material 2 subjected to such surface processing performs the surface processing on the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5. Compared with what is obtained by this, the feeling of glare etc. will be suppressed and it will become the thing especially excellent in the aesthetic appearance. Moreover, since the base material 2 is mainly composed of polycarbonate, the surface processing as described above can be performed relatively easily. Moreover, since the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5 are usually relatively thin, the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5 are subjected to surface processing. If applied, the silicon oxide layer 3, the zinc sulfide layer 4, and the coating film 5 may be completely removed from the surface-treated portion. Therefore, occurrence of such a problem can be effectively prevented.
Moreover, you may perform various washing | cleaning processes with respect to the surface of the base material 2 prior to the process mentioned later. Thereby, for example, the adhesion between the substrate 2 and the silicon oxide layer 3 can be made particularly excellent.

[Silicon oxide layer forming step]
Next, the silicon oxide layer 3 is formed on the first surface 21 of the substrate 2 (1b).
The method for forming the silicon oxide layer 3 is not particularly limited. For example, spin coating, dipping, brush coating, spray coating, electrostatic coating, electrodeposition coating, inkjet coating, etc., electrolytic plating, immersion plating, electroless Examples include wet plating methods such as plating, chemical vapor deposition methods (CVD) such as thermal CVD, plasma CVD, and laser CVD, dry plating methods (vapor deposition methods) such as vacuum deposition, sputtering, and ion plating, and thermal spraying. However, the dry plating method (vapor phase film forming method) is preferable. By applying a dry plating method (vapor phase film forming method) as a method for forming the silicon oxide layer 3, the silicon oxide layer 3 has a uniform and uniform film thickness and is in close contact with the substrate 2 and the zinc sulfide layer 4. The silicon oxide layer 3 having excellent properties can be reliably formed. As a result, the aesthetic appearance and durability of the finally obtained timepiece dial 1 can be made particularly excellent. Further, by applying a dry plating method (vapor phase film forming method) as a method for forming the silicon oxide layer 3, even if the silicon oxide layer 3 to be formed is relatively thin, Variation in (thickness) can be made sufficiently small. Therefore, for example, the light transmission of the timepiece dial 1 can be improved while the durability of the obtained timepiece dial 1 is sufficiently high. Therefore, the obtained timepiece dial 1 can be more suitably applied to a solar timepiece or the like. In addition, among the dry plating methods (vapor phase film forming methods) as described above, the above effects become more remarkable by applying vacuum deposition.

[Zinc sulfide layer formation process]
Next, the zinc sulfide layer 4 is formed on the silicon oxide layer 3 (1c).
The method for forming the zinc sulfide layer 4 is not particularly limited. For example, spin coating, dipping, brush coating, spray coating, electrostatic coating, electrodeposition coating, inkjet coating, etc., electrolytic plating, immersion plating, electroless Examples include wet plating methods such as plating, chemical vapor deposition methods (CVD) such as thermal CVD, plasma CVD, and laser CVD, dry plating methods (vapor deposition methods) such as vacuum deposition, sputtering, and ion plating, and thermal spraying. However, the dry plating method (vapor phase film forming method) is preferable. By applying a dry plating method (vapor phase film forming method) as a method for forming the zinc sulfide layer 4, the zinc sulfide layer 4 has a uniform and uniform film thickness and excellent adhesion to the silicon oxide layer 3. The zinc sulfide layer 4 can be reliably formed. As a result, the aesthetic appearance and durability of the finally obtained timepiece dial 1 can be made particularly excellent. Moreover, even if the zinc sulfide layer 4 to be formed is relatively thin by applying a dry plating method (vapor phase film forming method) as a method for forming the zinc sulfide layer 4, the film thickness (layer thickness) Variation in (thickness) can be made sufficiently small. Therefore, for example, the light transmission of the timepiece dial 1 can be improved while the durability of the obtained timepiece dial 1 is sufficiently high. Therefore, the obtained timepiece dial 1 can be more suitably applied to a solar timepiece or the like. In addition, among the dry plating methods (vapor phase film forming methods) as described above, the above effects become more remarkable by applying vacuum deposition.

[Coating film forming process]
Next, the coating film 5 is formed on the zinc sulfide layer 4 (1d). Thereby, the dial main body 10 is obtained.
The coating film 5 is formed by painting. Examples of the method for forming the coating film 5 (coating method) include spin coating, dipping, brush coating, spray coating, electrostatic coating, electrodeposition coating, and inkjet method, and spray coating is preferable. By applying spray coating as a method for forming the coating film 5, the coating film 5 can be easily and efficiently formed even if the coating film 5 has a relatively large thickness. Moreover, the dispersion | variation in the film thickness of the coating film 5 can be suppressed easily, and the aesthetic appearance of the timepiece dial 1 can be made especially excellent.

For the formation of the coating film 5, for example, a composition (composition for forming a coating film) containing components other than the constituent materials of the coating film 5 may be used. Examples of such components include a solvent and a dispersion medium. As the solvent and dispersion medium, liquids used as various solvents can be suitably used.
Moreover, when the coating film 5 to be formed includes a resin material, the coating film forming composition includes a resin material precursor (eg, monomer, dimer, oligomer, prepolymer, etc.). May be.

[Opening Step]
Next, an opening 101 is formed in a predetermined part of the dial body 10 (1e).
The opening 101 is usually formed at a site corresponding to the mounting site of the index member 6.
The opening 101 can be formed by, for example, cutting or punching.
Further, in this step, in addition to the attachment portion of the index member 6, for example, an opening may be formed in a portion through which a shaft of a needle (pointer) such as an hour hand, a minute hand, and a second hand should pass.

[Indicator member installation process]
Next, the foot portion 62 of the indicator member 6 is inserted into the opening 101 of the dial main body 10, and the indicator member 6 is fixed to the dial main body 10 (1f). At this time, the indicator member 6 is arranged such that the indicator portion 61 is disposed on the outer surface side of the dial main body 10.
The index member 6 may be fixed simply by inserting the foot 62 into the opening 101, but may be performed using an adhesive, for example. Thereby, especially the fixed strength with respect to the dial main body 10 of the index member 6 can be made excellent. In addition, when an adhesive is used to fix the indicator member in a conventional timepiece dial, the adhesive may be visually recognized by a user or the like, and the aesthetic appearance of the timepiece dial may be significantly reduced. However, in the present invention, the timepiece dial (the dial main body) is such that the base material, the silicon oxide layer, the zinc sulfide layer, and the coating film are arranged in the order as described above. Therefore, it is difficult for the user to visually recognize the adhesive. For this reason, the aesthetic appearance of the timepiece dial can be reliably improved.

As described above, the timepiece dial 1 can be obtained.
The silicon oxide layer forming step, the zinc sulfide layer forming step, and the coating film forming step as described above are performed on the base material 2 having a size and shape corresponding to the timepiece dial 1 to be manufactured. However, for example, it may be applied to the sheet-like substrate 2 and then processed into a desired size and shape by punching, cutting or the like.

<Clock>
Next, the timepiece of the present invention provided with the timepiece dial of the present invention as described above will be described.
The timepiece of the present invention has the timepiece dial of the present invention as described above. As described above, the timepiece dial of the present invention is excellent in light transmittance and decorativeness (aesthetic appearance). For this reason, the timepiece of the present invention provided with such a timepiece dial can sufficiently satisfy the requirements for a solar timepiece. As a part other than the timepiece dial (the timepiece dial of the present invention) that constitutes the timepiece of the present invention, known parts can be used. Hereinafter, an example of the configuration of the timepiece of the present invention will be described. explain.

FIG. 3 is a cross-sectional view showing a preferred embodiment of the timepiece (watch) of the present invention.
As shown in FIG. 3, a wristwatch (portable watch) 100 according to the present embodiment includes a case (case) 82, a back cover 83, a bezel (edge) 84, and a glass plate (cover glass) 85. . Further, in the case 82, the timepiece dial 1 of the present invention as described above, the solar cell 94, and the movement 81 are accommodated, and further, hands (pointers) not shown are accommodated. . The timepiece dial 1 is provided between the solar cell 94 and a glass plate (cover glass) 85, and the first surface 21 side of the base material 2 (the coating film 5 of the timepiece dial 1 is provided). The surface side) faces the solar cell 94 side, and the second surface 22 side of the substrate 2 (the surface side on which the indicator portion 61 of the timepiece dial 1 is provided) is a glass plate (cover glass) 85. It is arranged to face the side.

The glass plate 85 is usually made of transparent glass or sapphire having high transparency. Thereby, while being able to fully exhibit the aesthetics of the timepiece dial 1 of the present invention, a sufficient amount of light can be incident on the solar cell 94.
The glass plate 85 is usually made of transparent glass or sapphire having high transparency. Thereby, while being able to fully exhibit the aesthetics of the timepiece dial 1 of the present invention, a sufficient amount of light can be incident on the solar cell 94.
The movement 81 uses the electromotive force of the solar cell 94 to drive the pointer.

  Although omitted in FIG. 3, in the movement 81, for example, an electric double layer capacitor for storing the electromotive force of the solar cell 94, a lithium ion secondary battery, a crystal oscillator as a time reference source, and a crystal vibration A semiconductor integrated circuit that generates a driving pulse for driving a clock based on the oscillation frequency of the child, a step motor that drives the pointer every second in response to this driving pulse, and a wheel that transmits the movement of the step motor to the pointer A row mechanism is provided.

The movement 81 includes a radio wave receiving antenna (not shown). And it has the function to perform time adjustment etc. using the received electromagnetic wave.
The solar cell 94 has a function of converting light energy into electric energy. The electric energy converted by the solar cell 94 is used for driving the movement.
In the solar cell 94, for example, a p-type impurity and an n-type impurity are selectively introduced into a non-single-crystal silicon thin film, and a p-type non-single-crystal silicon thin film and an n-type non-single-crystal silicon thin film are used. It has a pin structure provided with an i-type non-single-crystal silicon thin film with a low impurity concentration in between.

A winding stem pipe 86 is fitted into and fixed to the barrel 82, and a shaft 871 of a crown 87 is rotatably inserted into the winding stem pipe 86.
The body 82 and the bezel 84 are fixed by a plastic packing 88, and the bezel 84 and the glass plate 85 are fixed by a plastic packing 89.
Further, a back cover 83 is fitted (or screwed) to the body 82, and a ring-shaped rubber packing (back cover packing) 92 is inserted in a compressed state in these joint portions (seal portions) 93. Has been. With this configuration, the seal portion 93 is sealed in a liquid-tight manner, and a waterproof function is obtained.

  A groove 872 is formed on the outer periphery of the middle portion of the shaft portion 871 of the crown 87, and a ring-shaped rubber packing (crown packing) 91 is fitted in the groove 872. The rubber packing 91 is in close contact with the inner peripheral surface of the winding stem pipe 86 and is compressed between the inner peripheral surface and the inner surface of the groove 872. With this configuration, the space between the crown 87 and the winding stem pipe 86 is liquid-tightly sealed, and a waterproof function is obtained. When the crown 87 is rotated, the rubber packing 91 rotates together with the shaft portion 871 and slides in the circumferential direction while being in close contact with the inner peripheral surface of the winding stem pipe 86.

Since the above portable watch (watch) is required to have particularly excellent durability (for example, impact resistance, etc.) among various types of watches, a book with excellent aesthetic appearance and excellent durability can be obtained. The invention can be applied more suitably.
In the above description, a wristwatch (portable clock) as a solar radio timepiece has been described as an example of a clock. However, the present invention is applicable to other types of clocks such as a portable clock, a table clock, a wall clock, etc. Can be applied similarly. Further, the present invention can be applied to any timepiece such as a solar timepiece excluding a solar radio timepiece and a radio timepiece excluding a solar radio timepiece.

The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above.
For example, in the timepiece dial and timepiece of the present invention, the configuration of each part can be replaced with any configuration that exhibits the same function, and any configuration can be added. For example, you may have a printing part formed by various printing methods.

Further, at least one layer (coat layer) may be provided on the surface of the timepiece dial (the surface on the side where the coating film is provided or the second surface of the substrate). Such a layer may be removed, for example, when the timepiece dial is used.
In the timepiece dial of the present invention, at least one layer is provided between the base material and the silicon oxide layer, between the silicon oxide layer and the zinc sulfide layer, and between the zinc sulfide layer and the coating film. The intermediate layer may be provided.
In the illustrated configuration, the coating film is provided on the entire surface of one side of the zinc sulfide layer. However, the coating film may be provided selectively on only a part thereof. For example, the coating film may be provided on the zinc sulfide layer so as to have a shape corresponding to a predetermined character or pattern.

  In the above-described embodiment, the timepiece dial is described as including an indicator member having a foot, but the indicator member may not have a foot. For example, the indicator member may be an adhesive member that is attached to the second surface side of the dial body, or may be formed by printing. Further, the timepiece dial of the present invention may not have an indicator member.

Next, specific examples of the present invention will be described.
1. Manufacture of timepiece dial (Example 1)
A timepiece dial was manufactured by the following method.
First, the base material which has the shape of the timepiece dial was produced by compression molding using polycarbonate, and then necessary portions were cut and polished. The obtained base material was substantially disk-shaped and had a diameter: 27 mm × thickness: 500 μm.

Next, this base material was washed. As the substrate cleaning, ultrasonic cleaning in a neutral detergent was performed for 10 minutes, water cleaning for 10 seconds, and pure water cleaning for 10 seconds.
Then, to form a silicon oxide layer formed of SiO ₂ on the first main surface is one main surface of the base material subjected to washing as described above (silicon oxide layer forming step). The formation of the silicon oxide layer was performed by the method described in detail below.

First, the cleaned substrate was mounted in a vacuum deposition apparatus, and then the inside of the vacuum deposition apparatus was evacuated (depressurized) to 1.3 × 10 ⁻⁴ Pa. Next, in such a state, a granule made of SiO ₂ having a purity of 99 wt% or more as an evaporation source was irradiated with an electron beam to form a film by vacuum deposition. The processing time for this vacuum deposition was 2 minutes. By such vacuum vapor deposition, a silicon oxide layer was formed on the first surface of the substrate. The formed silicon oxide layer was composed of 99 wt% or more of SiO ₂ . The thickness of the silicon oxide layer was 100 nm.

Next, a zinc sulfide layer composed of ZnS was formed on the surface provided with the silicon oxide layer without removing the substrate on which the silicon oxide layer was formed from the vacuum evaporation apparatus (zinc sulfide layer formation) Process). The formation of the zinc sulfide layer was performed by the method described in detail below.
Without removing the substrate on which the silicon oxide layer was formed from the vacuum deposition apparatus, the vacuum deposition apparatus was evacuated (reduced pressure) to 1.3 × 10 ⁻⁴ Pa, and subsequently a purity of 99 wt% or more as an evaporation source A granular product composed of ZnS was irradiated with an electron beam to form a film by vacuum deposition. The processing time for this vacuum deposition was 1 minute. By such vacuum deposition, a zinc sulfide layer was formed on the surface of the silicon oxide layer. The formed zinc sulfide layer was composed of 99 wt% or more of ZnS. Moreover, the thickness of the zinc sulfide layer was 30 nm.

Next, the base material on which the silicon oxide layer and the zinc sulfide layer are formed is taken out from the vacuum deposition apparatus, and a coating film is formed on the surface of the zinc sulfide layer (coating film forming step) to obtain a dial body. It was. The coating film was formed by the method described in detail below.
First, a coating film forming composition is prepared, which includes a powder (average particle size: 25 μm) of mica (mica) coated with TiO ₂ , a two-component curable urethane resin, and a thinner that functions as a solvent / dispersion medium. did.

Next, this coating film forming composition was applied to the surface of the zinc sulfide layer formed on the silicon oxide layer by spray coating.
Thereafter, the thinner was removed by heating, and the urethane resin was cured to form a coating film. The thickness of the coating film thus formed was 30 μm. The content of the in the coating powder (mica (powder coated with TiO ₂ mica)) was 25 wt%.

Next, an opening was formed in a portion of the dial main body obtained as described above where an index should be formed. The opening was formed by cutting. In this step, an opening was also formed at a site where the needle (pointer) shaft should penetrate.
Next, a separately produced index member was fixed to the opening of the dial main body (the opening of the part where the index is to be formed) to obtain a timepiece dial.

The indicator member is made of Ti and has an indicator portion and a foot portion, and the indicator portion faces the second surface side of the substrate (the surface side opposite to the surface on which the coating film is provided). Thus, the indicator member was inserted into the opening (see FIGS. 1 and 2).
Then, from the surface side where the coating film of the dial body is provided, an adhesive is injected into the opening into which the indicator member is inserted, and the adhesive is cured to fix the indicator member to the dial body, A clock dial was obtained.
In addition, the thickness of the base material, the silicon oxide layer, the zinc sulfide layer, and the coating film was measured according to a microscope cross-sectional test method defined in JIS H 5821.

(Examples 2 to 8)
The thickness of the substrate is as shown in Table 1, and the processing time in the silicon oxide layer forming step and the zinc sulfide layer forming step, the powder contained in the coating film forming composition (mica (mica)) Example 1 except that the composition of each layer is shown in Table 1 by adjusting the average particle size and content of the powder coated with TiO ₂ and the application amount of the coating film forming composition. A watch dial was manufactured in the same manner.

(Comparative Example 1)
A timepiece dial was manufactured in the same manner as in Example 1 except that the silicon oxide layer forming step was omitted.
(Comparative Example 2)
A timepiece dial was manufactured in the same manner as in Example 1 except that the zinc sulfide layer forming step was omitted.

(Comparative Example 3)
A timepiece dial was manufactured in the same manner as in Example 1 except that the coating film forming step was omitted.
(Comparative Example 4)
A timepiece dial was manufactured in the same manner as in Example 1 except that the coating film forming step was performed prior to the silicon oxide forming step and the zinc sulfide forming step. That is, in this comparative example, the dial main body was such that the base material, the coating film, the silicon oxide layer, and the zinc sulfide layer were arranged in this order from the outer surface side (observer side). .

(Comparative Example 5)
A timepiece dial was manufactured in the same manner as in Example 1 except that the coating film forming step was performed between the silicon oxide forming step and the zinc sulfide forming step. That is, in this comparative example, the dial main body was such that the base material, the silicon oxide layer, the coating film, and the zinc sulfide layer were arranged in this order from the outer surface side (observer side). .
(Comparative Example 6)
A timepiece dial was manufactured in the same manner as in Example 1 except that the order of the zinc sulfide forming step and the silicon oxide forming step was changed. That is, in this comparative example, the dial main body was such that the base material, the zinc sulfide layer, the silicon oxide layer, and the coating film were arranged in this order from the outer surface side (observer side). .

(Comparative Example 7)
A watch dial was manufactured in the same manner as in Example 1 except that a thin film made of MgF ₂ having a purity of 99 wt% or more was used as the evaporation source instead of a thin film made of SiO ₂ having a purity of 99 wt% or more. . That is, in this comparative example, instead of the silicon oxide layer, it had a magnesium fluoride layer composed of MgF ₂ . The magnesium fluoride layer was composed of 99 wt% or more of MgF ₂ .

(Comparative Example 8)
A watch dial is manufactured in the same manner as in Example 1 except that a thin film made of Ti ₃ O ₅ with a purity of 99 wt% or more is used as the evaporation source instead of a thin film made of ZnS with a purity of 99 wt% or more. did. That is, in this comparative example, instead of the zinc sulfide layer, a titanium oxide layer composed of Ti ₃ O ₅ was included. The titanium oxide layer was composed of 99 wt% or more of Ti ₃ O ₅ .

(Comparative Example 9)
As the evaporation source, a thin film made of MgF ₂ having a purity of 99 wt% or more is used instead of a thin film made of SiO ₂ having a purity of 99 wt% or more, and a purity of 99 wt instead of a thin film made of ZnS having a purity of 99 wt% or more A watch dial was manufactured in the same manner as in Example 1 except that a thin film composed of at least% Ti ₃ O ₅ was used. That is, in this comparative example, instead of the silicon oxide layer, it has a magnesium fluoride layer composed of MgF ₂ , and instead of the zinc sulfide layer, titanium oxide composed of Ti ₃ O ₅ It had a layer. The magnesium fluoride layer was composed of 99 wt% or more of MgF ₂ , and the titanium oxide layer was composed of 99 wt% or more of Ti ₃ O ₅ .

(Comparative Example 10)
A timepiece dial was manufactured in the same manner as in Example 1 except that instead of polycarbonate, an acrylonitrile-butadiene-styrene copolymer (ABS resin) was used as the base material.
(Comparative Example 11)
A timepiece dial was manufactured in the same manner as in Example 1 except that the coating film was formed on the second surface of the substrate. That is, in this comparative example, the dial main body was such that the coating film, the substrate, the silicon oxide layer, and the zinc sulfide layer were arranged in this order from the outer surface side (observer side). .

Table 1 summarizes the configuration of the timepiece dial of each example and each comparative example. In Table 1, polycarbonate is indicated by PC, and ABS resin is indicated by ABS. Moreover, about the comparative example (Comparative Examples 7-9) which has a magnesium fluoride layer and a titanium oxide layer, the conditions of these each layer were shown in the column of the silicon oxide layer and the zinc sulfide layer, respectively. Moreover, the refractive indexes of the metal compound layers (silicon oxide layer, zinc sulfide layer, magnesium fluoride layer, titanium oxide layer) formed in the above examples and comparative examples were as follows. That is, the refractive index of the zinc sulfide (ZnS) layer is 2.30, the refractive index of the silicon oxide (SiO ₂ ) layer is 1.46, the refractive index of the magnesium fluoride (MgF ₂ ) layer is 1.38, and The refractive index of the titanium oxide (Ti ₃ O ₅ ) layer was 2.25. Table 1 also shows the stacking order of each layer (including the base material and the coating film) constituting the timepiece dial. In Table 1, in the column indicating the stacking order, the base material is “B”, the silicon oxide layer is “SiO ₂ ”, the zinc sulfide layer is “ZnS”, the coating film is “P”, and the magnesium fluoride layer is “ MgF ₂ ”and the titanium oxide layer are indicated by“ Ti ₃ O ₅ ”.

2. Visual appearance evaluation For each timepiece dial manufactured in each of the above Examples and Comparative Examples, the surface side on which the indicator portion is arranged (except for Comparative Example 11, a coating for the timepiece dial was provided. The surface side opposite to the surface, and Comparative Example 11 was visually observed from the surface side provided with the coating film of the timepiece dial, and the appearance was evaluated according to the following six-stage criteria. .

A: It has an extremely excellent appearance.
B: It has an excellent appearance.
C: It has a good appearance.
D: Appearance is slightly poor.
E: Appearance is poor.
F: The appearance is extremely poor.

3. Appearance evaluation by chromaticity meter For the timepiece dial manufactured in each of the above examples and comparative examples, the surface side on which the indicator portion is arranged (except for Comparative Example 11, a coating film for the timepiece dial is provided. For the comparative example 11, the chromaticity (a ^* b ^* ) of the surface on which the coating film of the timepiece dial was provided was measured for a chromaticity meter (Minolta, CM- 2022) and evaluated according to the following four-stage criteria.

A: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, a ^*
Is -4 to 4 and b ^* is within the range of -4 to 4.
B: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, a ^*
Is in the range of -8 to 8 and b ^* is in the range of -8 to 8 (except for the range of A).
C: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, a ^*
Is −13 to 13 and b ^* is within the range of −13 to 13 (except for the range of A and B).
D: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, a ^*
Is −13 to 13 and b ^* is out of the range of −13 to 13.
As the light source of the colorimeter was a _{D 65} defined in JIS Z 8720, and measurements were taken at a viewing angle 2 °.

Further, according to the ^L * ^a * ^{b *} display ^{L *} values to the following four levels of the chromaticity diagram defined in JIS Z 8729, were evaluated.
A: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, L ^* is 75 ≦ L ^* ≦ 90.
B: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, L ^* is 55 ≦ L ^* <75.
C: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, L ^* is 45 ≦ L ^* <55.
D: In the chromaticity diagram of L ^* a ^* b ^* display specified by JIS Z 8729, L ^* is L ^* <45.

4). Variation in reflectance in the visible light region About the timepiece dial manufactured in each of the above examples and comparative examples, the surface side on which the indicator portion is arranged (except for Comparative Example 11, the coating on the timepiece dial is Reflection at each wavelength in the visible light region (wavelength region of 380 to 780 nm) of the surface opposite to the provided surface, for Comparative Example 11, the surface side on which the coating film for the timepiece dial is provided. The rate was measured. From this measurement result, in the visible light region (wavelength region of 380 to 780 nm), the reflectance A [%] at the wavelength where the reflectance is maximum and the reflectance B [%] at the wavelength where the reflectance is minimum. The difference AB was obtained and evaluated according to the following five-stage criteria. It can be said that the smaller the value of AB, the smaller the variation in reflectance in the visible light region. The reflectance was measured in a state where a solar cell was arranged on the back side of the timepiece dial.

A: The value of AB is less than 7%.
B: The value of AB is 7% or more and less than 12%.
C: The value of AB is 12% or more and less than 20%.
D: The value of AB is 20% or more and less than 30%.
E: The value of AB is 30% or more.

5. Evaluation of Light (Visible Light) Transmittance of Timepiece Dial The light transmittance of each timepiece dial produced in each of the above Examples and Comparative Examples was evaluated by the following method.
First, the solar cell and each clock dial were placed in a dark room. Thereafter, light from a fluorescent lamp (light source) separated by a predetermined distance was made incident on the light receiving surface of the solar cell alone. At this time, the power generation current of the solar cell was A [mA]. Next, light from a fluorescent lamp (light source) separated by a predetermined distance as described above was made incident on the upper surface of the light receiving surface of the solar cell in a state where the timepiece dial was overlapped. In this state, the generated current of the solar cell was B [mA]. Then, the light transmittance of the timepiece dial represented by (B / A) × 100 was calculated and evaluated according to the following four criteria. It can be said that the larger the light transmittance, the better the light transmittance of the timepiece dial. In addition, the timepiece dial is the surface side on which the indicator portion is disposed (except for Comparative Example 11, the surface side opposite to the surface provided with the coating film of the timepiece dial, for Comparative Example 11, The timepiece dial was superposed so that the surface on which the coating film of the timepiece dial was provided faced the fluorescent lamp (light source) side. Further, as the white fluorescent lamp, high white (FL15N-B) manufactured by Hitachi Lighting Co., Ltd. was used.
A: 28% or more.
B: 25% or more and less than 28%.
C: 15% or more and less than 25%.
D: Less than 15%.

  Thereafter, a watch as shown in FIG. 3 was manufactured by using the timepiece dial manufactured in each of the above Examples and Comparative Examples. Then, each manufactured wristwatch was put in a dark room. Thereafter, light from a fluorescent lamp (light source) spaced a predetermined distance was made incident from a surface on the dial side (surface on the glass plate) of the watch. At this time, the irradiation intensity was changed at a constant speed so that the irradiation intensity of light gradually increased. As a result, the movement of all the timepieces of the present invention and the timepieces of the comparative examples were driven even when the irradiation intensity was relatively small.

6). Evaluation of radio wave permeability The radio wave permeability of each timepiece dial manufactured in each of the above Examples and Comparative Examples was evaluated by the following method.
First, a watch case and a wristwatch internal module (movement) equipped with an antenna for receiving radio waves were prepared.
Next, a watch internal module (movement) and a watch dial were assembled in the watch case, and the radio wave reception sensitivity in this state was measured.

Using the reception sensitivity in a state where the timepiece dial is not incorporated as a reference, the reduction amount (dB) of the reception sensitivity when the timepiece dial is incorporated was evaluated according to the following four criteria. It can be said that the lower the radio wave reception sensitivity is, the better the radio wave transmission of the timepiece dial is. In addition, the timepiece dial is the surface side on which the indicator portion is disposed (except for Comparative Example 11, the surface side opposite to the surface provided with the coating film of the timepiece dial, for Comparative Example 11, The timepiece dial was superposed so that the face side provided with the coating film faced to the outer surface side.
A: No decrease in sensitivity is observed (below the detection limit).
B: A decrease in sensitivity is observed at less than 0.7 dB.
C: The decrease in sensitivity is 0.7 dB or more and less than 1.0 dB.
D: The decrease in sensitivity is 1.0 dB or more.

7). Adhesion evaluation of film About each timepiece dial manufactured in each of the above Examples and Comparative Examples, two kinds of tests as shown below were performed, and a film (silicon oxide layer, zinc sulfide layer, coating film, The adhesion of the magnesium fluoride layer and the titanium oxide layer was evaluated.
7-1. Bending test For each timepiece dial, a steel bar with a diameter of 4 mm was used as a fulcrum, and after bending 30 ° with respect to the center of the timepiece dial, the appearance of the timepiece dial was visually observed, These appearances were evaluated according to the following four criteria. Bending was performed in both compression / tension directions.
A: No floating or peeling of the film is observed.
B: Floating of the film is hardly recognized.
C: The float of the film is clearly recognized.
D: Cracking and peeling of the film are clearly recognized.

7-2. Thermal cycle test Each timepiece dial was subjected to the following thermal cycle test.
First, the watch dial is placed in a 20 ° C. environment for 1.5 hours, then in a 60 ° C. environment for 2 hours, then in a 20 ° C. environment for 1.5 hours, and then in a −20 ° C. environment. It was left to stand for 3 hours. Thereafter, the environmental temperature was returned again to 20 ° C., which was set as one cycle (8 hours), and this cycle was repeated three times in total (24 hours in total).

Thereafter, the appearance of the timepiece dial was visually observed, and the appearance was evaluated according to the following four-stage criteria.
A: No floating or peeling of the film is observed.
B: Floating of the film is hardly recognized.
C: The float of the film is clearly recognized.
D: Cracking and peeling of the film are clearly recognized.

8). Evaluation of Indicator Visibility (Ease of Visibility) A watch as shown in FIG. 3 was assembled using the dials for watches manufactured in each of the above examples and comparative examples (however, the indicator part was arranged). Surface side (except for Comparative Example 11, the surface side opposite to the surface provided with the watch dial coating film, and for Comparative Example 11, the surface side provided with the watch dial coating film ) Was placed facing the outer surface side). Each watch thus obtained was visually observed, and the visibility of the index (time visibility) was evaluated according to the following six-stage criteria.

A: Extremely excellent visibility.
B: It has excellent visibility.
C: Good visibility.
D: Visibility is slightly poor.
E: Visibility is poor.
F: Visibility is extremely poor.
These results are shown in Table 2.

  As can be seen from Table 2, all of the timepiece dials of the present invention had an excellent aesthetic appearance and excellent light transmittance. In addition, the timepiece dial of the present invention has excellent adhesion to a base material composed of polycarbonate (silicon oxide layer, zinc sulfide layer, coating film) and has excellent durability. It was. In addition, the timepiece dial of the present invention was excellent in radio wave transmission. In addition, the timepiece dial of the present invention was excellent in the visibility of the index (time visibility).

On the other hand, in the comparative example, a satisfactory result was not obtained. That is, the timepiece dial of each comparative example could not simultaneously satisfy the excellent aesthetic appearance, the excellent light transmission, and the durability as a timepiece dial.
Further, a timepiece as shown in FIG. 3 was assembled using the timepiece dials obtained in the respective Examples and Comparative Examples. Each timepiece thus obtained was tested and evaluated in the same manner as described above, and the same results as described above were obtained.

It is sectional drawing which shows suitable embodiment of the timepiece dial of this invention. It is sectional drawing which shows suitable embodiment of the manufacturing method of the timepiece dial of this invention. It is a fragmentary sectional view which shows suitable embodiment of the timepiece (portable timepiece) of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Dial for timepiece 2 ... Base material (board | substrate) 21 ... 1st surface 22 ... 2nd surface 3 ... Silicon oxide layer 4 ... Zinc sulfide layer 5 ... Coating film 6 ... Indicator member 61 ... Indicator part 62 ... Foot part 10 ... Dial body 101 ... Opening 94 ... Solar cell 81 ... Movement 82 ... Body (case) 83 ... Back cover 84 ... Bezel (edge) 85 ... Glass plate (cover glass) 86 ... Winding pipe 87 ... Crown 871 ... Shaft part 872 ... Groove 88 ... Plastic packing 89 ... Plastic packing 91 ... Rubber packing (crown packing) 92 ... Rubber packing (back cover packing) 93 ... Joint (seal part) 100 ... Wristwatch (portable watch)

Claims (4)

A watch dial used for a solar watch equipped with a solar cell,
A substrate composed primarily of polycarbonate;
A zinc sulfide layer provided on the first surface side, which is one main surface of the base material, and mainly composed of ZnS ;
A silicon oxide layer provided between the base material and the zinc sulfide layer and mainly composed of SiO ₂ ;
Wherein the said surface facing the silicon oxide layer of a zinc sulfide layer provided on the opposite side of, is made of a material containing a coloring agent and / or a diffusing agent, it possesses a coating film having optical transparency ,
An indicator is provided on the second surface side, which is the main surface opposite to the first surface of the base material,
The timepiece dial is used such that the second surface, which is the main surface opposite to the first surface of the base material, faces the outer surface side (observer side),
The silicon oxide layer has a thickness of 20 to 200 nm;
The zinc sulfide layer has a thickness of 10 to 100 nm,
A timepiece dial having a total thickness of 50 to 250 nm of the silicon oxide layer and the zinc sulfide layer . The timepiece character according to claim 1 , wherein the coating film has a configuration in which mica (mica) is coated with TiO ₂ and is formed of a material containing powder having an average particle diameter of 1 to 30 μm. Board. For the timepiece dial, the color tone of the second surface side, which is the main surface opposite to the first surface of the base material, is the color of the L ^* a ^* b ^* display defined by JIS Z 8729 in time diagram, ^{a *} is -8～8, and timepiece dial according to claim 1 or 2 ^{b *} is -8～8. A watch comprising a solar cell and a cover glass disposed on the outer surface side of the solar cell,
The timepiece dial according to any one of claims 1 to 3 is provided between the solar cell and the cover glass.
The timepiece dial is arranged such that a second surface, which is a main surface opposite to the first surface of the base material, faces the cover glass side.

Images