JP2002161390A - Exterior part of clock and film forming method thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a white-metal based exterior-part of clock with high surface hardness and superior corrosion resistance. SOLUTION: A method for manufacturing the aimed exterior part of clock comprises, plating a base 11 of the exterior part of clock with either one coating film 12 of an amorphous Ni-W alloy film, an amorphous Ni-W alloy film, an amorphous Fe-W alloy film, a nanocrystal structured Ni-W alloy film, or a nanocrystal structured Fe-W alloy film, any of which has high hardness and high corrosion resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a watch exterior component such as a watch case, a bezel, a back cover, or a band, and a method for forming a coating on the watch exterior component.

[0002]

2. Description of the Related Art Conventionally, there are watch exterior parts coated with a film having high hardness and high corrosion resistance. For example, there is a watch case or band made of brass as a base, coated on its surface with a nickel plating film with a thickness of several tens of μm as an intermediate layer, and further coated with a titanium nitride film with a thickness of several thousand angstroms. . These watch cases and bands have a Vickers hardness of HV1000 or more, and are JIS2371.
It is a high hardness and high corrosion resistant watch exterior part that does not show any rust even in a salt spray test (SST test) based on JIS.

[0003]

However, the colors of these watch cases and bands are limited to gold-based colors, and there has been a problem that the product variations cannot be expanded. As for the watch exterior, a white metal system is mainly used as represented by stainless steel. For many years, there has been a demand for watch exterior parts coated with a white metal-based film having high hardness and high corrosion resistance in order to widen product variations.

[Object of the Invention] An object of the present invention is to solve the above-mentioned problems and to provide a watch exterior component coated with a white metal-based film having high hardness and high corrosion resistance, and a method of forming a coating on the watch exterior component. It is to provide.

[0005]

Means for Solving the Problems In order to achieve the above object, a watch exterior part and a method for forming a film on the watch exterior part of the present invention employ the following means.

The watch exterior component of the present invention is characterized in that a coating film made of an amorphous nickel-tungsten alloy film or an amorphous iron-tungsten alloy film is provided on the base surface of the watch exterior component.

A watch exterior part according to the present invention is characterized in that a coating film made of a nanocrystalline nickel-tungsten alloy film or a nanocrystalline iron-tungsten alloy film is provided on the base surface of the watch exterior part. .

[0008] The watch exterior component of the present invention is characterized in that the base material of the watch exterior component is stainless steel, brass or zinc.

[0009] The watch exterior component of the present invention is characterized in that the watch exterior component is a watch case, a bezel, a back cover, or a band.

The timepiece exterior component of the present invention is characterized in that an intermediate layer is provided between the base of the timepiece exterior component and the coating film.

In the timepiece exterior part according to the present invention, the intermediate layer provided between the base of the timepiece exterior part and the coating film is made of nickel or a nickel alloy.

In the method for forming a coating on a watch exterior part according to the present invention, the watch exterior part is provided with a coating film made of an amorphous nickel-tungsten alloy film or an amorphous iron-tungsten alloy film on a base surface of the watch exterior part. The method for forming a coating on a substrate is characterized in that the coating is formed by plating.

In the method for forming a coating on a watch exterior part according to the present invention, a coating film made of a nanocrystalline nickel-tungsten alloy film or a nanocrystalline iron-tungsten alloy film is provided on the base surface of the watch exterior part. The method for forming a coating on a watch exterior part is characterized in that the coating is formed by forming a plating film by a plating method and then heat-treating the plating film in an inert gas atmosphere.

[Action] The watch exterior part of the present invention has an amorphous nickel (Ni) on the base surface of the watch exterior part.
-Tungsten (W) alloy film, amorphous iron (Fe)
-A tungsten alloy film, a nanocrystalline Ni-W alloy film,
It is characterized in that one of the coating films of the nanocrystalline Fe—W alloy film is provided. Stainless steel, brass, zinc, etc. are applied as base materials for watch exterior parts.

These amorphous Ni—W alloy films, amorphous Fe—W alloy films, nanocrystalline Ni—W alloy films, and nanocrystalline Fe—W alloy films all have a white metallic color, High hardness and high corrosion resistance. By providing these coating films on the watch exterior parts, the present invention has realized a white metal-based watch exterior part having high hardness and high corrosion resistance.

Specifically, a coating film made of an amorphous Ni—W alloy film or an amorphous Fe—W alloy film is formed on a base material such as stainless steel, brass, zinc, or the like by a plating method. It is characterized by forming a nanocrystalline structure alloy film or a coating film of a nanocrystalline structure alloy film by subjecting a base material such as brass or zinc to a plating method and a heat treatment in an inert gas atmosphere.

Further, when the base material of the watch exterior part of the present invention is made of brass or zinc having poor corrosion resistance, a nickel or nickel alloy film is provided between the base and the coating film in order to improve the corrosion resistance. May be interposed as an intermediate layer. This intermediate layer is used to improve the corrosion resistance of watch exterior parts.
We use supplementarily.

As described above, in the timepiece exterior part of the present invention, the base surface is made of an amorphous Ni-W alloy film and an amorphous F
The problem was solved by providing a coating film of any of an e-W alloy film, a nanocrystalline Ni-W alloy film, and a nanocrystalline Fe-W alloy film.

The amorphous Ni—W alloy film, amorphous Fe—W alloy film, nanocrystalline Ni—W alloy film, and nanocrystalline Fe—W alloy film applied as the coating film in the present invention are as follows. It has various features. (A) High hardness and low scratch resistance. (B) Excellent corrosion resistance.

Further, in the film forming method of the present invention, a coating film is formed on the amorphous Ni—W alloy film and the amorphous Fe—W alloy film by a plating method, and the nanocrystalline structure Ni—W
The W alloy film and the nanocrystalline structure Fe-W alloy film are formed by forming a plating film by a plating method, and then performing a heat treatment in an inert gas atmosphere to form a coating film on the watch exterior part. Settled.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A watch exterior part and a method of forming a film thereon according to a preferred embodiment of the present invention will be described below with reference to the drawings. First, the configuration of the watch exterior component according to the embodiment of the present invention will be described with reference to the cross-sectional view of FIG.

As shown in FIG. 1, an amorphous Ni—W alloy film, an amorphous Fe— alloy film is formed on the surface of a base 11 made of stainless steel, brass, zinc or the like as a watch case.
A coating film 12 of one of a W alloy film, a nanocrystalline Ni—W alloy film, and a nanocrystalline Fe—W alloy film is provided. By forming any one of these coating films 12, it is possible to provide a watch exterior part having high hardness, being hardly damaged, and having excellent corrosion resistance. As a watch exterior component, a coating film 12 of the present invention can be provided not only on a watch case but also on a watch bezel, a back cover, and a watch band.

[0023]

Next, an embodiment of a method for forming a coating on a watch exterior part according to the present invention will be described. First, a first embodiment will be described.

Example 1 A plating bath having the following composition, pH (pH), and bath temperature was prepared. _{NiSO 4 · 6H 2 O: 0.05mol} / l Na 3 C 6 H 5 O 7 · 2H 2 O: 0.6 mol / l Na 2 WO 4 · 2H 2 O: 0.15mol / l NH 4 Cl: 0 0.4 mol / l NaBr: 0.17 mol / l pH: 7.7 Bath temperature: 70 ° C.

The entire surface of the base 11 composed of a watch case made of SUS304 was plated at a current density of 17.5 A / dm ² for 1 hour using the above-mentioned plating bath. As a result, a coating film 12 composed of a 25 at% W-Ni alloy film having a thickness of 10 μm was obtained. The structure of the Ni—W alloy film was amorphous.

The watch case on which the coating film 12 made of the above amorphous Ni-W alloy film is formed has a surface hardness of HV750, and is subjected to a salt spray test (SST test) based on Japanese Industrial Standard (JIS) 2371. After 96 hours, it did not rust at all and had excellent corrosion resistance.

As described above, by coating the base 11 of the watch case made of SUS304 with the coating film 12 made of an amorphous Ni-W alloy film by plating, a white metal having high surface hardness and excellent corrosion resistance is obtained. A system watch case can be realized.

Example 2 A plating bath having the following composition, pH, and bath temperature was prepared. _{Fe (NH 4) (SO 4} ) · 12H 2 O: 0.05mol / l Na 3 C 6 H 5 O 7 · 2H 2 O: 0.5 mol / l Na 2 WO 4 · 2H 2 O: 0.15mol / 1 NH ₄ Cl: 0.5 mol / l NaBr: 0.16 mol / l pH: 8.5 Bath temperature: 80 ° C.

As an intermediate layer, a current density of 20 A / dm was applied to the entire surface of a base 11 composed of a watch bezel made of zinc and coated with nickel having a thickness of 50 μm on the surface by using the plating bath described above. ² was subjected to 2 hours plating. The intermediate layer made of nickel was formed by plating.

As a result, 27.5 at% of a film thickness of 20 μm was obtained.
A coating film 12 made of a W—Fe alloy film was obtained on the watch bezel surface. The structure of the Fe—W alloy film was amorphous.

The watch bezel on which the coating film 12 made of the above amorphous Fe-W alloy film was formed had a surface hardness of HV850, and was subjected to a salt spray test for 96 hours. Was excellent.

In this way, the watch bezel made of zinc material is coated with the amorphous Fe—W alloy film as the coating film 12 by plating, so that the watch bezel having a high surface hardness and excellent corrosion resistance can be provided in the present invention. realizable.

Example 3 A plating bath having the following composition, pH, and bath temperature was prepared. _{NiSO 4 · 6H 2 O: 0.05mol} / l Na 3 C 6 H 5 O 7 · 2H 2 O: 0.6 mol / l Na 2 WO 4 · 2H 2 O: 0.15mol / l NH 4 Cl: 0 0.4 mol / l NaBr: 0.17 mol / l pH: 7.7 Bath temperature: 70 ° C.

As an intermediate layer, a current density of 17.5 A / A was applied to the entire surface of the base 11 composed of a watch case made of brass whose surface was coated with nickel having a film thickness of 50 μm by using the plating bath described above. Plating was performed at dm ² for 1 hour and 30 minutes. The intermediate layer made of nickel was formed by plating. As a result, 25 at% W-Ni having a thickness of 15 μm was obtained.
A plating film made of an alloy film was obtained.

Further, the plating film was heated at a temperature of 450 ° C.
The coating film 12 was formed by heat treatment for 1 hour in a nitrogen atmosphere as an inert gas. The structure of the coating film 12 was a very fine nanocrystal structure in which the size of crystal grains was on the order of nanometers (nm).

The watch case on which the coating film 12 made of the above-mentioned nanocrystalline Ni—W alloy film was formed had a surface hardness of HV1200, and was subjected to a salt spray test (SST test) for 96 hours. It did not rust and had excellent corrosion resistance.

As described above, by forming the nanocrystalline Ni-W alloy film on the brass watch case by performing the plating method and the heat treatment in an inert gas atmosphere, the present invention has a high surface hardness and excellent corrosion resistance. A white metal watch case can be realized.

Example 4 A plating bath having the following composition, pH, and bath temperature was prepared. _{Fe (NH 4) (SO 4} ) · 12H 2 O: 0.05mol / l Na 3 C 6 H 5 O 7 · 2H 2 O: 0.5 mol / l Na 2 WO 4 · 2H 2 O: 0.15mol / 1 NH ₄ Cl: 0.5 mol / l NaBr: 0.16 mol / l pH: 8.5 Bath temperature: 80 ° C.

The entire surface of the base 11 composed of a watch band made of SUS304 was plated at a current density of 20 A / dm ² for 2 hours and 30 minutes using the above plating bath. As a result, a plating film composed of a 27.5 at% W—Fe alloy film having a thickness of 25 μm was obtained.

Thereafter, the plating film is heated at a temperature of 450.
The coating film 12 was formed by heat treatment at a temperature of 1 ° C. for 1 hour in a nitrogen atmosphere as an inert gas. The structure of the coating film 12 was a nano-crystal structure as in Example 3.

The watch band on which the coating film 12 made of the nanocrystalline Fe—W alloy film was formed had a surface hardness of HV1150, and was subjected to a salt spray test (SST test) for 96 hours. It did not rust and had excellent corrosion resistance.

As described above, in the SUS304 watch band,
By forming a coating film 12 made of a nanocrystalline Fe-W alloy film by performing a plating method and a heat treatment in an inert gas atmosphere, a white metal watch band having high surface hardness and excellent corrosion resistance is realized. It is possible to do.

In the above description, an example was described in which nickel was used as the intermediate layer, but a nickel alloy can also be used. As the nickel alloy, nickel-phosphorus (Ni-P)
And nickel-boron (Ni-B).

Further, as a method of forming the intermediate layer,
In addition to the plating method described above, a physical vapor deposition (PVD) method or a chemical vapor deposition (CVD) method is also applicable.

Further, as the material of the intermediate layer, stainless steel can be used in addition to nickel and nickel alloy.

[0046]

As described above, the watch exterior component of the present invention can be used to obtain a white metal based watch having a high surface hardness and excellent wear resistance. Further, in the watch exterior component of the present invention, a watch exterior component having excellent corrosion resistance can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a watch case which is one of the watch exterior parts according to an embodiment of the present invention.

[Explanation of symbols]

 11: Base 12: Coating film

Claims (8)

[Claims] 1. A timepiece exterior part, comprising: an amorphous nickel-based material on a base surface of the timepiece exterior part.
A watch exterior part comprising a coating film made of a tungsten alloy film or an amorphous iron-tungsten alloy film. 2. A timepiece exterior part, wherein a nickel crystal nano-structure is provided on a base surface of the timepiece exterior part.
A watch exterior part comprising a coating film made of a tungsten alloy film or a nanocrystalline iron-tungsten alloy film. 3. The base material is made of stainless steel, brass,
The watch exterior part according to claim 1, wherein the watch exterior part is zinc. 4. The watch exterior component according to claim 1, wherein the watch exterior component is a watch case, a bezel, a back cover, or a band. 5. The watch exterior part according to claim 1, wherein an intermediate layer is provided between the base and the coating film. 6. The watch exterior part according to claim 5, wherein the intermediate layer is made of nickel or a nickel alloy. 7. An amorphous nickel-tungsten alloy film or an amorphous iron film is formed on a base surface of a watch exterior part.
What is claimed is: 1. A method for forming a coating on a watch exterior part provided with a coating film made of a tungsten alloy film, wherein the coating film is formed by plating. 8. A nano-crystalline nickel-tungsten alloy film or a nano-crystalline iron on a base surface of a watch exterior part.
A method for forming a coating on a watch exterior part provided with a coating film made of a tungsten alloy film, wherein the coating film forms a plating film by a plating method, and thereafter, the plating film is formed in an inert gas atmosphere. A method for forming a coating on a watch exterior part, wherein the coating is formed by heat treatment.