JPS61163263A - Golden color exterior parts - Google Patents

Abstract

PURPOSE:To reduce the thickness of a gold (alloy) film by forming a golden color compound film of hafnium nitride or hafnium carbonitride on a metal or heat resistant base material and forming further the gold (alloy) film thereon thereby decreasing the change in the color tone owing to the partial wear of the resulted golden color exterior parts. CONSTITUTION:A wristwatch case, etc. made of a stainless steel as a base material are set in an ion plating device and after the inside of said device is evacuated to a vacuum, Hf is heated and evaporated by an electron beam to form discharge plasma in an N2 atmosphere, thereby forming the golden color composite film of hafnium nitride on the above-mentioned case. The inside of the same device is evacuated to a vacuum again and thereafter gold is evapo rated by the electron beam to form the gold film. The same effect is obtd. even by forming the film of hafnium nitride of hafnium carbonitride by the other physical vapor deposition method or chemical vapor deposition method and the gold (alloy film) by another vapor plating method such as sputtering or wet process plating method.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a golden exterior part used for a watch case, a watch band, an eyeglass frame, an accessory, etc.

[Summary of the invention]

Traditionally, gold, gold alloys, and their plated products have been used as gold-colored exterior parts, but in recent years, with the aim of reducing costs, gold-colored and hard titanium nitride has been coated with physical vapor deposition.
In order to further improve the color tone, there are gold-colored exterior parts made of gold or gold alloy formed on the base.

However, when gold or gold alloy is formed on titanium nitride, when the metal wears away, the underlying titanium nitride layer is exposed, and the underlying titanium nitride layer has a dark tone, giving it a foreign feel.

Therefore, the present invention is to research the hard compound closest to the color tone of gold or gold alloy, use hafnium nitride or hafnium carbonitride as a base layer, and form a gold or gold alloy layer thereon.

According to this invention, even if the gold layer is worn out, the underlying layer is hard and the color tone is very close to that of gold, so it does not give a foreign feeling.

[Conventional technology]

Traditionally, gold alloy materials and their plating products have been used for gold-colored exterior parts, but in recent years, vapor phase plating methods, which are superior to physical vapor deposition methods, have developed, and gold-colored super-hardened compounds such as titanium nitride have been used. Gold-colored exterior parts were also known, in which a film was developed and this was used as a base layer, and gold or a gold alloy was formed on top of the film. For example, Japanese Patent Publication No. 59-26664 discloses a golden exterior part using this technique.

[Problem that the invention seeks to solve]

However, conventional gold-plated materials and gold-plated products have the drawback of high cost, and when gold is coated on titanium nitride, the underlying titanium nitride layer is exposed when the gold is worn away. This titanium nitride has a lower reflectance to visible light than gold and gold alloys, so it feels darker, and because of its reflectance characteristics, it has a greenish tinge, giving it a different feel from gold and gold alloys. It had a drawback.

Therefore, in order to solve these conventional drawbacks, the present invention has the following features:
The objective is to obtain a gold-colored exterior part that is inexpensive and whose color change due to wear is minimized.

[Failure to solve the problem]

In order to solve the above-mentioned problems, the present invention has developed hafnium nitride trenches as an underlayer by applying physical vapor deposition such as ion blasting or sputtering, or chemical vapor deposition using thermal reaction or plasma to a metal or heat-resistant substrate. The method uses a golden coating of hafnium carbonitride, and a gold or gold alloy coating is formed as an upper layer by a vapor phase plating method such as vacuum evaporation, ion blasting, or sputtering, or a wet plating method such as electroplating.

[Effect]

As mentioned above, hafnium nitride and hafnium carbonitride, which are formed on metal or heat-resistant substrates, have a higher reflectance than titanium nitride, and the color tone is closer to gold or gold alloys, so the upper layer Even if the gold casing or gold alloy coating becomes worn and partially exposed, it does not give any strange feeling.

〔Example〕

The present invention will be explained below based on Examples.

[Example 1] After cleaning a stainless steel watch case with an organic solvent, an acid, and an alkali, it was set in a jig installed in an ion blating device called an active reaction vapor deposition method.
After evacuation to X 1.0-II Torr, lX1
Hafnium was evaporated by heating with an electronic vino in a nitrogen atmosphere of 0-'' Torr, and a discharge plasma was formed using an ion blating mechanism to form about 1 μm of golden hafnium nitride on a wristwatch case set in a jig. Using the same device, test again 5X 10- without turning off the vacuum.
Evacuation was performed at 5 TOrr '1, and gold was evaporated with an electron beam to form a gold exposure of approximately 01 μηL. The watch case thus obtained had a beautiful golden color, just like gold.

[Example 2] Similar to Example 1, a stainless steel watch case was cleaned and set in an ion brating device, and a 5×10
Evacuate to '-5 Torr and reduce nitrogen partial pressure I x 1
．． 0 ”-” TOrr, acetylene partial pressure 2X1'0
-'Torr while introducing nitrogen and acetylene, elino-fnium is evaporated by electron beam heating, and a discharge plasma is formed by the ion braking mechanism, and gold-colored hafnium carbonitride is placed on the set watch case. A thickness of 1 μm was formed. Next, stop evaporating hafnium and stop introducing nitrogen and acetylene.
After evacuation to TOrr again, create an argon gas atmosphere.
Gold containing approximately 5% nickel by weight was evaporated by resistance heating and subjected to high frequency ion blating to form a coating of approximately 0.05μm, resulting in a wristwatch case with a gold-colored coating extremely similar to gold, known as so-called Hamilton gold. I was able to get

[Example 5] After cleaning a stainless steel watch band in the same manner as in Example 1,
Set in the ion brating device 5X 10-'
Evacuate to TOrr and reduce nitrogen partial pressure to 1×10”-’
Torr, acetylene partial pressure 2X i O-' To
While nitrogen and acetylene are introduced into the RR process, electron beam heating is applied to evaporate hafnium and a discharge plasma is created by the ion brating mechanism. 1
μm was formed. Next, the introduction of nitrogen and acetylene and the evaporation of hafnium were stopped, and the temperature was increased again to 5X 10-' Torr.
exhaust to. Next, nickel was evaporated by electron beam heating, and ion blating was performed to form a nickel film of about 0.05 μm on the hihafnium carbonitride. After that, the watch band was exposed to the atmosphere, and wet plating was applied to pure gold to a thickness of approximately 0.05μm.When heat treatment was performed at 500℃ for 50 minutes in a non-oxidizing atmosphere, the nickel layer was removed during the gold plating. It was thermally diffused and turned into a gold alloy with a color similar to Hamilton gold.

The samples prepared using the methods described in Examples 1 to 5 above were subjected to a cowhide sliding wear test 50,000 times at a load of 5002.
Although hafnium nitride or hafnium carbonitride in the lower layer appeared in some parts, the difference in color tone was at such a level that almost no difference in color tone could be recognized with the naked eye. Further, in this wear test, there was no wear of the hafnium nitride or hafnium carbonitride coating layer. Historically, in Example 6, a nickel film layer of about 0.05 μm was formed between the carbonitride carbonitride and the gold plating layer, but the gold plating layer was worn out because it almost completely diffused and alloyed with the gold due to heat treatment. However, the color tone of nickel did not appear, but the color tone of hafnium carbonitride appeared, and no difference was observed from the samples of Examples 1 and 2.

〔Effect of the invention〕

As explained above, this invention forms a gold 1 or gold alloy coating on a gold-colored hafnium nitride or carbonitride coating, so that even if the gold or gold alloy coating is partially worn out, the underlying layer Because hafnium nitride and hafnium carbonitride have very similar color tones, they are hardly noticeable. Therefore, the thickness of the gold or gold alloy coating can be reduced to approximately one hundredth of that of conventional gold plating, resulting in a significant cost reduction. In addition, in the examples, stainless steel watch cases and watch bands were used as the treated items, but the materials used include metals such as copper alloys such as brass, plating products thereof, and other heat-resistant base materials without any problems. It is clear that the present invention can be applied not only to watch-related exterior parts but also to all kinds of gold-colored exterior parts. In a naive example, hafnium nitride and hafnium carbonitride films were formed by ion blating, but
It may be formed by physical vapor deposition such as sputtering or chemical vapor deposition using thermal reaction or plasma.

that's all

Claims (1)

[Claims] A golden exterior component characterized in that a gold or gold alloy coating is formed on a golden compound coating of hafnium nitride or hafnium carbonitride formed on a metal or a heat-resistant base material.