JP2003073886A - Exterior parts for watch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide exterior parts for a watch, which restrain increase of the price while maintaining qualities on the appearance and functions. SOLUTION: An objective method for manufacturing the parts is characterized by employing Pt plating instead of Pd plating, for finishing plating, namely, forming a primary plated layer 4 on a material 2 of a cast zinc and forming the finish plated layer 6 thereon by plating Pt. Then, the method reduces a use amount of the material and consequently reduces the cost, because the Pt plated layer requires only thickness of 1/5 for acquiring equal corrosion resistance to that of the Pd plated layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timepiece exterior component using a zinc cast material, and more particularly to a finish plating layer thereof.

[0002]

2. Description of the Related Art Conventionally, cases, register rings,
Zinc cast is often used for exterior parts for watches such as bands. This watch exterior component is made of a zinc cast material, and is plated with several types of plating to enhance its corrosion resistance and decorativeness.
It was completed.

The plating layer formed on the surface of the above material is
It is roughly divided into a base plating layer and a finish plating layer.
As the base plating layer, a first plating layer formed by Cu plating for the purpose of preventing rust on the surface of the material,
Ni plating, Cu-Sn alloy plating, or Cu- which is applied on the first plating layer for the purpose of preventing Cu from rusting.
There was a second plating layer or the like formed by Sn—Zn alloy plating or the like. On the other hand, as the finish plating layer, P is used for the purpose of providing a decorative feeling of a noble metal on the above base plating layer.
There was a plating layer formed by applying Au plating on d plating, Au plating or Pd plating.

The Pd plating is used for finishing the appearance color to a white metallic luster. When the appearance color is finished to a golden metallic luster, Au plating is applied or the corrosion resistance of the base plating is improved. In addition, Pd plating was applied thinly and then Au plating was applied for the purpose of suppressing the diffusion reduction of the bonding interface at high temperature.

The thickness of the finish plating is 0.5 to 3 μm for Pd plating in the case of white finish, 0.1 to 2 μm in Pd plating and 0.05 to Au for gold finish.
It was set to 2 μm.

[0006]

In the exterior parts for a timepiece, the finish quality is extremely important because the appearance quality thereof is so important as to determine the commercial value. However, recently, the price of precious metals used for finish plating has risen sharply, and the price of exterior parts for watches using zinc cast, which is used in relatively inexpensive watches, has increased while maintaining the appearance quality and functional quality. Is required to be suppressed.

The present invention has been made in view of the above-mentioned problems of the prior art, and suppressed the price increase while maintaining the appearance quality and the functional quality by selecting the precious metal used for finish plating and setting the plating thickness. The present invention provides exterior parts for watches.

[0008]

According to a first aspect of the present invention, there is provided a timepiece exterior component having a plating layer formed on a surface thereof by plating a zinc cast material, It has a finish plating layer formed by applying Pt plating. The finish plating layer in this watch exterior component is 0.2 to 0.5 μ.
It has a thickness of m.

The timepiece exterior component of the present invention, as claimed in claim 3, is a timepiece exterior component having a plating layer formed on the surface by plating a zinc cast material with Pt plating. The finish plating layer includes a Pt plating layer formed by the above process and an Au plating layer formed by applying Au plating on the Pt plating layer. The Pt plating layer in the timepiece exterior component has a thickness of 0.1 to 0.5 μm, and the Au plating layer has a thickness of 0.05 to 2 μm.

The plating layer formed on the surface of the zinc cast material in the timepiece exterior component has a first plating layer formed by applying Cu plating, and the first plating layer and the second plating layer. It has a base plating layer composed of a second plating layer formed by applying Ni plating on the first plating layer. The first plating layer of the timepiece exterior component has a thickness of 10 to 23 μm, and the second plating layer has a thickness of 10 to 15 μm.

The plating layer formed on the surface of the zinc cast material in the timepiece exterior component has a first plating layer formed by applying Cu plating, and It has a base plating layer including a second plating layer formed by performing Cu—Sn alloy plating or Cu—Sn—Zn alloy plating on the first plating layer. In this timepiece exterior component, the first plating layer has a thickness of 10 to 23 μm, and the second plating layer has a thickness of 2 to 4 μm.

The plating layer formed on the surface of the zinc cast material in the timepiece exterior component has a first plating layer formed by applying Cu plating, and A second plating layer formed by applying Cu-Sn alloy plating or Cu-Sn-Zn alloy plating on the first plating layer, and Cu-Sn on the second plating layer subjected to honing. Alloy plating or C
It has a base plating layer composed of a third plating layer formed by applying u-Sn-Zn alloy plating.
The first plating layer in this timepiece exterior component is 10
Has a thickness of ˜23 μm, and the second plating layer has a thickness of 2 to 4
The third plating layer has a thickness of 2 to 4 μm.

The plating layer formed on the surface of the material of the zinc cast in the timepiece exterior component may be formed according to claim 11.
As shown in FIG. 4, the plating layer formed on the surface of the zinc cast material is a first plating layer formed by applying Cu plating, and a bright Ni layer on the first plating layer.
A second plating layer formed by plating,
It has a base plating layer consisting of a third plating layer formed by applying satin Ni plating on the second plating layer. In this exterior component for a watch, the first plating layer has a thickness of 10 to 23 μm, the second plating layer has a thickness of 10 to 15 μm, and the third plating layer has a thickness of 7 to 10 μm. have.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the timepiece exterior component of the present invention, a Pd plating using a soaring Pd is used instead of the Pd plating.
By using Pt plating using t, cost is reduced while maintaining appearance quality and functional quality.

That is, a zinc plating material is subjected to underplating to form an underplating layer, and then a Pt plating is applied thereon to form a finish plating layer. This Pt
Shows a white metallic luster of the same color as Pd, and when comparing the surface hardness of the plating layer, Pt has a hardness almost twice that of Pd. Therefore, even if the Pd plating as the finish plating is replaced with the Pt plating, the color tone does not change, and the hardness can be improved. In particular, in the case of Pt plating, in order to obtain the same corrosion resistance as the finish plating layer by Pd plating, the plating thickness of 1/5 is sufficient, so the amount of material used can be reduced and the cost can be reduced. Becomes

[0016]

EXAMPLES The construction of the timepiece exterior parts according to the examples of the present invention will be described below. FIG. 1 is a sectional view showing a plating structure of a timepiece exterior component according to an embodiment of the present invention. In FIG. 1, 2 is a material made of zinc cast, and 4 is a material 2.
Is a base plating layer formed on the surface of. The base plating layer 4 is formed by applying Cu plating for the purpose of preventing rust of the material 2 and then applying Ni plating, Cu-Sn alloy plating, Cu-Sn-Zn alloy plating, etc. for the purpose of preventing rust of the Cu plating layer. It is formed by applying it, and the details of the plating thickness and the like will be described later.

Reference numeral 6 is a finish plating layer formed by applying Pt plating on the base plating layer 4. This P
The finish plating layer 6 composed only of the t plating layer 6a is for finishing to a white metallic luster, and when finishing to a golden metallic luster, as shown in FIG. 6a is formed, and Au plating is applied thereon to form an Au plated layer 6b.

Regarding the plating layer of the Pt plating layer 6a,
Corrosion resistance tests such as an artificial sweat test for observing discoloration and a salt spray test for observing the occurrence of rust were carried out by setting the Pt plating thicknesses respectively. Further, the same test was performed on the conventional Pd plating, and the Pt plating and the Pd plating were compared, and the evaluation results shown in Table 1 were obtained.

[0019]

[Table 1]

In the above artificial sweat test, sodium chloride 9.9 g / l, sodium sulfide 0.8 g / l, urea 1.
9 g / l, lactic acid 1.7 ml / l, ammonia water 0.2 m
An artificial sweat composition liquid was prepared by mixing 1 / l, and the artificial sweat composition liquid was immersed in a liquid temperature of 40 degrees for 24 hours to confirm the discolored state.

As a salt spray test, a 5% solution of sodium chloride was sprayed for 8 hours at a liquid temperature of 35 ° C., and generation of rust was confirmed.

From the test results shown in Table 1 above, it was confirmed that the Pt plating thickness was 0.2 to 1.0 μm as a preferable range for the Pt plating single layer. Further, no significant change in corrosion resistance was observed in the plating thickness range of 0.5 to 1.0 μm, and it was found that a thickness of up to 0.5 μm is sufficient in consideration of the plating cost.

Further, as shown in Table 1, Pt plating and P
Comparing the plating thickness of d plating, the test result when the plating thickness of Pt plating is 0.1 μm corresponds to the plating thickness of Pd plating of 0.5 μm, and when the plating thickness of Pt plating is 0.2 μm, The test result corresponds to a Pd plating thickness of 1.0 μm and a Pt plating thickness of 0.5.
The test result when the thickness is μm is the plating thickness of Pd plating 2.
This corresponds to 0 μm. From this result, it was found that in the case of Pt plating, a corrosion resistance effect equivalent to that of Pd plating can be obtained with a plating thickness of ⅕ of Pd plating. Therefore, in order to obtain the same corrosion resistance as the conventional Pd plating, Pt
In the case of plating, a plating metal amount of 1/5 is sufficient. Therefore, if the price per gram of Pt is 5 times or less than the price per gram of Pd, the cost of Pt plating can be lower than that of Pd plating.

Regarding the surface hardness, Pt has a hardness almost twice that of Pd, so that the Pt plated layer 6a is more effective in terms of wear resistance.

Table 2 shows the Pt plating layer 6a for finishing the white metallic luster shown in FIG. 1 and the finish plating layer for laminating the Pt plating layer 6a and the Au plating layer 6b for finishing the golden metallic luster shown in FIG. In terms of thickness, as in Table 1, a suitable plating thickness range obtained by the evaluation tests of the artificial sweat test and the salt spray test is described. Moreover, the thickness contrast with the case where the conventional Pd plating is performed is also shown.

[0026]

[Table 2]

From Table 2, Au which gives a golden metallic luster
When the plating layer 6b is overlaid on the Pt plating layer 6a, the thickness of the Pt plating layer 6a can be allowed up to the range of 0.1 μm. It was found that this is a range in which the corrosion resistance is improved by stacking the Au plating layer 6b and the Pt plating thickness of 0.1 μm can be sufficiently used. The Au plating layer 6b applied on the Pt plating layer 6a has a plating thickness of 0.05.
The range of up to 2.0 μm is preferable. When the thickness is less than 0.05 μm, a sufficient gold color tone cannot be obtained, and when the thickness is more than 2.0 μm, the material cost only increases and it makes little sense.
In the case of a timepiece exterior component using a zinc cast material, a thickness of 2.0 μm is sufficient in terms of cost, corrosion resistance and wear resistance.

Further, as can be seen from Table 2, Pt
Even when the Au plating layer 6b is provided on the plating layer 6a, the Pt plating layer 6a can be remarkably thinner than the conventional Pd plating, so that the material cost can be remarkably reduced.

Next, a plating configuration example including the details of the base plating layer 4 will be described with reference to FIGS. 3 to 6. In the plating configuration of the timepiece exterior component shown in FIG. 3, the base plating layer 4 is a first plating layer 4a formed by plating the surface of the material 2 with Cu, and the first plating layer 4a.
The second plating layer 4b is formed by applying Ni plating on a. The finish plating layer 6 described above is formed on the second plating layer 4b.

The first plating layer 4a formed by the Cu plating is provided to prevent corrosion of the material 2 and to improve the adhesion and gloss of the second plating layer 4b. The Cu plating forming the first plating layer 4a is
Cyan-based strike copper plating is followed by copper sulfate plating. The plating thickness at that time is
Strike copper plating is applied to 2 to 3 μm and then copper sulfate plating is applied to set the total thickness to 10 to 23 μm.

Further, Ni is formed on the first plated layer 4a.
The second plated layer 4b formed by plating is provided to further improve the corrosion resistance of the first plated layer 4a and to provide gloss. The thickness of the second plated layer 4b is 10 to
It is set to 15 μm.

The finish plating layer 6 composed of the Pt plating layer 6a formed by Pt plating on the second plating layer 4b in the base plating layer 4 is formed to finish the white metallic luster as described above. The plating thickness is set to 0.2 to 0.5 μm as described above.

The finish plating layer 6 has a plating thickness set in consideration of the results of the above-mentioned tests and the plating cost, and the first plating layer 4a and the second plating layer 4 serving as the base plating layer 4 are set. For 4b, the plating thickness is set by performing the same test.

That is, the lower limit of each plating thickness can be confirmed as the lower limit of corrosion-free from the results of each test, and the upper limit of each plating thickness is not limited to the result of the above test. It is set by considering the cost and dimension management. That is, in the case of the first plating layer 4a formed by Cu plating, the corrosion resistance is improved up to the plating thickness of 10 to 23 μm, but even if the thickness is further increased, the remarkable corrosion resistance is not recognized, and conversely the plating cost Rises,
There is a problem that dimensional control becomes difficult. For this reason,
It has been recognized that it is optimal to set the upper limit of the plating thickness to 23 μm. Further, the upper limit of the second plating layer 4b is similarly set. In the case of the second plated layer 4b, if it is formed too thick, cloudiness may occur in the color tone and the gloss may be lowered, so that the gloss is obtained while maintaining the corrosion resistance.

Regarding the plating thickness of the base plating layer 4, a bending test for observing the adhesion of the plating is performed by forming the first and second plating layers 4a and 4b on the material 2. Consideration is also given to the result of confirming the peeling of the plating when bent at 360 degrees.

As described above, the base plating layer 4 is formed by forming the first plating layer 4a of Cu plating to a thickness of 10 to 23 μm and the second plating layer 4b of Ni plating to a thickness of 10 to 15 μm. Provided, Pt by Pt plating
By providing the finish plating layer 6 in which the plating layer 6a is formed to have a thickness of 0.2 to 0.5 μm, sufficient corrosion resistance can be obtained, and a white metal luster and a cheaper exterior component for a watch are provided. Can be formed.

FIG. 4 is a sectional view showing a plating structure of a timepiece exterior component in which a base plating layer 4 is formed without using Ni metal. In this exterior component for a watch, N shown in FIG.
The second plating layer 4b formed by i plating is replaced with Cu
It replaces the second plating layer 4c formed by -Sn alloy plating or Cu-Sn-Zn alloy plating.
The plating thickness of the second plating layer 4c is set to 2 to 4 μm. Also regarding this plating thickness, confirm the lower limit of the plating thickness from the results of the above-mentioned tests as the lower limit of corrosion-free. In addition to the result of the above test, the upper limit of the plating thickness is set to a value that takes into consideration the plating cost, dimensional control, gloss and the like. Other than that, the first plating layer 4a and the finish plating layer 6 are the same as those shown in FIG.

It is said that Ni metal may cause metal allergy when it comes into direct contact with the skin. Cu-Sn alloy plating or Cu-Sn-Zn instead of Ni plating
Those plated with alloy are very effective in preventing metal allergies.

FIG. 5 is a cross-sectional view of a timepiece exterior component showing a plating configuration for finishing in a satin finish. Since the exterior parts for this watch are finished in a satin tone, C shown in FIG. 4 is used.
Honing such as sand blasting is performed on the surface of the second plating layer 4c formed by u-Sn alloy plating or Cu-Sn-Zn alloy plating to form a satin pattern 4d.

Further, Cu-S is formed on the second plated layer 4c having a satin-finished pattern 4d formed on the surface by honing.
The third plating layer 4e is formed by performing n-alloy plating or Cu-Sn-Zn alloy plating. This third
Since the plating layer 4e of No. 2 is made of the same alloy as the second plating layer 4c, it is well adapted to the pattern 4d of the second plating layer 4c and does not impair the satin feeling.
A finish plating layer 6 made of a Pt plating layer 6a is formed on the third plating layer 4e, and a satin finish pattern appears on the surface of the finish plating layer 6 to finish the finish in a satin finish.

The first plating layer 4a formed by the Cu plating, the second plating layer 4c formed by the Cu--Sn alloy plating or the Cu--Sn--Zn alloy plating, and the Pt plating layer formed by the Pt plating. The plating thickness of 6a is set similarly to that of the timepiece exterior component shown in FIGS. 3 and 4. Also, Cu-Sn alloy plating or Cu-Sn
The plating thickness of the third plating layer 4e formed by the Zn alloy plating is set to 2 to 4 μm, and also with respect to this plating thickness, from the results of the above-mentioned tests, the lower limit of the plating thickness does not cause corrosion. The numerical value that can be confirmed as the lower limit is set, and the upper limit of the plating thickness is set not only in the result of the above test but also in consideration of the plating cost, dimensional control, gloss and the like.

As described above, even when finished in a satin finish by honing, it is possible to reduce the cost of the exterior parts for a watch having a white metallic luster excellent in corrosion resistance.

FIG. 6 is a cross-sectional view of a timepiece exterior component showing a plating configuration in the case where a satin finish is achieved only by plating without using honing. In this timepiece exterior component, the second plating layer 4f is formed by performing bright Ni plating on the first plating layer 4a formed by Cu plating as in the case of the timepiece exterior component described above. Then, the third plating layer 4g is formed by performing satin finish Ni plating on the second plating layer 4f. The third plating layer 4g is formed by composite plating in which solid fine particles are mixed with Ni plating.
The solid fine particles 4i project from the surface of and the fine irregularities are formed on the surface, and this becomes the satin finish. The finish plating layer 6 made of the Pt plating layer 6a is formed on the third plating layer 4g, and a matte pattern appears on the surface thereof.

The plating thickness of the first plating layer 4a formed by the Cu plating and the Pt plating layer 6a formed by the Pt plating are set in the same manner as that of the timepiece exterior component shown in FIGS. 3 to 5. . Further, the plating thickness of the second plating layer 4f formed by the bright Ni plating is 10 to 15 μm,
The plating thickness of the plating layer 4g is set to 7 to 10 μm. With respect to each plating thickness, the lower limit of each plating thickness can be confirmed to be the lower limit of corrosion-free from the results of the above-mentioned tests. Further, the upper limit of each plating thickness is set not only in the result of the above test but also in consideration of the plating cost, dimensional control, gloss and the like.

The satin-finished Ni plating is the Ni-plated layer 4h.
Ni for forming is mixed with solid fine particles 4i made of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, silicon carbide, tungsten carbide, zirconium carbide, boron carbide, boron nitride, chromium boride or the like for plating. It is something to give. The particle size of the solid fine particles 4i used in the present embodiment is 3 to 5 μm, but 0.01 to 10 μ in consideration of the thickness of the third plating layer 4g and the like.
It is possible to use solid fine particles 4i having a particle diameter of about m.

As described above, even when the matte finish is finished by plating, it is possible to reduce the cost of the exterior parts for a watch having a white metallic luster excellent in corrosion resistance.

In the plating structure of the exterior parts for a watch shown in FIGS. 3 to 6, the finish plating layer 6 is composed of only the Pt plating layer 6a in order to finish it to a white metallic luster, but a gold-based metal is used. In order to make it glossy, as shown in FIG. 2, the Au plating layer 6b is formed on the Pt plating layer 6a.
To form the finish plating layer 6. As shown in Table 1, the plating thicknesses of the Pt plating layer 6a and the Au plating layer 6b in this case are 0.1 to 0.5 μm and 0.05, respectively.
˜2 μm.

The plating processing conditions for each of the above-mentioned platings are set as shown in Tables 1 and 2. The plating thickness of each plating is determined by the immersion time in the bath liquid under the plating conditions shown in Tables 3 and 4, and the plating thickness can be adjusted by changing the current value.

[0049]

[Table 3]

[0050]

[Table 4]

[0051]

According to the present invention, a base plating layer is formed on a material made of zinc cast, and a Pt plating layer is formed thereon as a finish plating layer. Therefore, it is formed as a conventional finish plating layer. The same corrosion resistance can be obtained with a plating thickness of about 1/5 as compared with the Pd plating layer. As a result, if the material costs of Pd and Pt are the same, the material cost of the plated metal can be reduced to about ⅕ of the conventional one.

Further, since the thickness of the finish plating layer is thin, the plating time can be reduced to about 1/3 of the conventional time, and the cost can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a plating configuration of a timepiece exterior component having a white metallic luster according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a plating configuration of a timepiece exterior component having a golden metallic luster according to an embodiment of the present invention.

FIG. 3 is a sectional view showing a detailed plating configuration of the timepiece exterior component shown in FIG.

4 is a cross-sectional view showing another detailed plating configuration of the timepiece exterior component shown in FIG.

5 is a cross-sectional view showing another detailed plating configuration of the timepiece exterior component shown in FIG.

6 is a cross-sectional view showing another detailed plating configuration of the timepiece exterior component shown in FIG.

[Explanation of symbols]

2 material 4 Underplating layer 4a First plating layer 4b, 4c, 4f Second plating layer 4e, 4g Third plating layer 4h Ni plating layer 4i solid particles 6 Finish plating layer 6a Pt plating layer 6b Au plating layer

Claims (12)

[Claims] 1. A watch exterior part having a plating layer formed on a surface thereof by plating a zinc cast material, the watch exterior part having a finish plating layer formed by applying Pt plating. Exterior parts. 2. The finish plating layer is 0.2 to 0.5 μm.
The exterior component for a timepiece according to claim 1, having a thickness of m. 3. A watch exterior component having a plating layer formed on a surface thereof by plating a zinc cast material, wherein the Pt plating layer is formed by Pt plating, and the Pt plating layer is formed on the Pt plating layer. An exterior part for a timepiece having a finish plating layer composed of an Au plating layer formed by applying Au plating. 4. The Pt plating layer has a thickness of 0.1 to 0.5 μm.
The exterior part for a timepiece according to claim 3, wherein the Au plating layer has a thickness of 0.05 to 2 µm. 5. The plating layer formed on the surface of the zinc cast material is a first plating layer formed by applying Cu plating, and Ni plating is applied on the first plating layer. The exterior component for a timepiece according to claim 1, further comprising a base plating layer including a second plating layer formed by the method. 6. The exterior component for a timepiece according to claim 5, wherein the first plating layer has a thickness of 10 to 23 μm, and the second plating layer has a thickness of 10 to 15 μm. 7. The plating layer formed on the surface of the zinc cast material is a first plating layer formed by applying Cu plating, and Cu-S on the first plating layer.
The timepiece exterior according to any one of claims 1 to 4, further comprising a base plating layer including a second plating layer formed by performing n-alloy plating or Cu-Sn-Zn alloy plating. parts. 8. The exterior component for a timepiece according to claim 7, wherein the first plating layer has a thickness of 10 to 23 μm, and the second plating layer has a thickness of 2 to 4 μm. 9. The plating layer formed on the surface of the zinc cast material is a first plating layer formed by applying Cu plating, and Cu-S on the first plating layer.
a second plating layer formed by performing an n-alloy plating or a Cu-Sn-Zn alloy plating, and a Cu-Sn alloy plating or a Cu-Sn-Zn mixture on the second plating layer subjected to the honing. The timepiece exterior component according to any one of claims 1 to 4, further comprising a base plating layer including a third plating layer formed by performing gold plating. 10. The first plating layer has a thickness of 10 to 23 μm.
10. The exterior component for a timepiece according to claim 9, wherein the second plating layer has a thickness of 2 to 4 μm, and the third plating layer has a thickness of 2 to 4 μm. . 11. The plating layer formed on the surface of the zinc cast material is a first plating layer formed by applying Cu plating, and a gloss N is formed on the first plating layer.
It has a base plating layer including a second plating layer formed by i plating and a third plating layer formed by applying satin Ni plating on the second plating layer. The exterior part for a timepiece according to any one of claims 1 to 4, which is characterized. 12. The first plating layer has a thickness of 10 to 23 μm.
12. The timepiece exterior component according to claim 11, wherein the second plating layer has a thickness of 10 to 15 μm, and the third plating layer has a thickness of 7 to 10 μm. .