JPH08238118A - Precious metal accessory with colored film - Google Patents

Abstract

PURPOSE: To provide a precious metal accessory having a new type of colored film in purple or black. CONSTITUTION: 1) On a precious metal accessory main body, a colored film comprising a colored film of purple or black comprising gold-aluminum alloy formed on the precious metal accessory main body formed by an ion plating method, and an aluminum-based transparent protective film formed on the colored film is formed. 2) The colored film is formed comprising the aluminum- based transparent protective film of aluminum nitride (AlN). 3) The colored film is formed comprising the aluminum-based protective film of aluminum oxide (Al2 O3 ). A precious metal accessory having the colored film is thus formed in clear purple or black, thereby a new type of highly decoractive precious metal accessories can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precious metal jewelry which has a new colored film such as purple or black.

[0002]

2. Description of the Related Art In the precious metal jewelry industry, there is an urgent need to develop new products that meet consumer needs. At present, gold and platinum are often used for decorative precious metal materials due to the increasing tendency to be genuine, but these materials are limited to K18 golden color and platinum white color as colored metals. However, there is a limit to the design in the situation of individualization and differentiation.

Therefore, it is possible to develop an original product if a new colored film can be formed by making the best use of the characteristics of the material and without degrading the quality as a precious metal. Part 1
As an example, as disclosed in JP-A-60-5872, a means has been developed for vapor-depositing aluminum on a gold product and producing AuAl ₂ which is purple by thermal diffusion at 600 ° C.

However, in the above conventional example, the material is made of gold.
Limited to products and heat diffusion of gold and aluminum
Is purple AuAl₂Other than AuAl , Au₂Al Etc gold
The formation of intergeneric compounds suppresses the tint of colored films
There was a drawback that

Further, the above vapor-deposited coating has a problem in durability, and has not been put into practical use yet, and has not been a product.

[0006]

Therefore, the inventors of the present invention have conducted earnest research on a technique for forming a colored film by an ion plating method which has excellent adhesion and is capable of forming a hard film.

As a result, reproducible conditions for forming a purple-colored film can be determined based on various experiments using gold-aluminum alloy as an evaporation material. Further, by using nitrogen as a gas for ionization, Reacts with aluminum of the gold-aluminum alloy, which is the evaporation material,
N (aluminum nitride) was generated and it became possible to form a black film.

[0008] However, as a film for an accessory, so-called durability which is not discolored while having a high altitude is indispensable.

As a result of various studies, by forming a transparent film of aluminum nitride having high hardness (Hv 1000 or more) and durability on a colored film of purple, black or the like,
It has become possible to provide a precious metal jewelry having a colored film that is durable and has no practical problems.

That is, the precious metal jewelry having a colored film of the present invention can be obtained by using a gold aluminum alloy as a metal for evaporation to obtain a product having a colored film of bright purple, black or the like, and further during use. The film may peel off,
The object of the present invention is to provide a precious metal accessory that is extremely excellent in commercial value and has no drawbacks such as discoloration.

[0011]

Means for Solving the Problems That is, a colored precious metal jewelry of the present invention comprises a precious metal jewelry body,
The present invention is characterized by having a colored film of purple, black or the like made of a gold-aluminum alloy formed on a body of a jewelry accessory by an ion plating method, and an aluminum-based transparent protective film formed on the colored film.

The precious metal jewelry formed with a colored film of the present invention is also characterized in that the aluminum-based transparent protective film is aluminum nitride (AlN).

Further, the precious metal jewelry formed with the colored film of the present invention is also characterized in that the transparent protective film of aluminum vapor is aluminum oxide (Al ₂ O ₃ ).

One of the features of the precious metal jewelry with the colored coating of the present invention is that the colored coating has a thickness of 0.1 μm or more.

The gold-aluminum alloy that can be preferably used in the present invention is preferably an alloy containing gold of about 80% and aluminum of about 20% as main components.

[0016]

Since the colored film-formed precious metal jewelry of the present invention is constructed as described above, the obtained colored film-formed precious metal jewelry has vivid purple and black colors, and is a novel and highly decorative precious metal jewelry. It has become possible to provide.

Since the precious metal jewelry having the colored coating of the present invention is constructed as described above, a coating having sufficient durability for practical use can be obtained. Moreover, the obtained film has a smooth and dense structure, and it is possible to obtain a product having excellent commercial value without defects such as rough skin and pinholes.

[0018]

EXAMPLES Examples of precious metal jewelry with a colored coating of the present invention will be described in detail below. [Embodiment 1] FIG. 1 shows an example of a precious metal jewelry which has a colored film to be obtained according to the present invention, and shows a ring having two color tones. And the light colored part 2 on the surface of the ring 1
Indicates gold, and the dark portion 3 indicates the noble metal forming the purple film obtained in the present invention.

The vapor deposition conditions for film formation are shown below. (Deposition conditions) Evaporated metal Au 99.99%, Al 99.99% Substrate temperature 250 ° C Temperature control time 30min Jig rotation speed 10 rpm RF 250W bias 2000V Argon pressure 2 × 10 ^-2 Pa At that time, gold content of gold aluminum alloy Experiments were carried out with various evaporation materials with different values. (Substrate sample) 50 × 100 of brass plate (6.4 brass)
Surface roughness Ra = 0.03 μm 40 × 100 × 2 mm of a glass plate was subjected to alkali degreasing by ultrasonic cleaning and acetone degreasing by the same cleaning, and dried before use. (Evaporation Material) A: AuAl ₂ (78% Au) B: Au75 / Al25 C: Au78 / Al22 D: Au80 / Al20 E: Au85 / Al15 F: Au90 / Al10 Evaporated for 5 minutes under the above conditions to form Spectral reflectance of the film (ICP emission spectrophotometer ICPS-10
00II (manufactured by Shimadzu Corp.) and color coordinates. The results are shown in the graph of FIG.

The known purple gold-aluminum alloy material A has a light absorption in the vicinity of 550 nm and has a purple surface. On the other hand, the coating film due to the composition change of the gold-aluminum alloy has absorption near 550 nm when the gold content is 80% (D) to 85% (E), and has a color tone close to the purple color of the known purple gold-aluminum alloy material A. Was becoming. Gold 75
% (B) and 78% (C), a white surface similar to aluminum was formed, and 90% (F) gold formed a yellow film close to gold. (Film change due to evaporation time) Thickness of the above film is 0.1μ
If it is less than m, it is thin in practical use. Therefore, we decided to see the change of the coating with the elapse of evaporation time.

A: 1 min b: 8 min c: 13 min d: 20 min The film formed by time change was measured by spectral reflectance and color coordinates. The results are shown in the graph of FIG.

Thus, the deposition time is 1 minute, 8 minutes, 13
After 20 minutes and 20 minutes (increased film thickness), the color of the surface changed, changing from white to purple and then to grayish. This is because the gold content on the surface increased due to the progress of evaporation. That is, when the composition of gold aluminum of the film deposited on the glass plate was analyzed by ICP, the gold contents were 42% (a), 68% (b),
It became 73.6% (c) and 79.7% (d). As a result of the above, the vapor deposition of the alloy material must be sufficiently considered because the vapor deposition time greatly affects the film formation. Therefore, the vapor deposition time of this alloy was set to about 13 minutes since the purple color became vivid at 8 minutes (b) to 13 minutes (c). (Bias voltage) Evaporation conditions for film formation include electron beam current for sample dissolution, bias voltage, high frequency output, etc. as factors. The electron beam current for melting the gold-aluminum alloy was set to 350 mA because melting of the sample started at 200 mA and the output of the electron beam was too high and the temperature was too high at 400 mA, and the bumping of the sample was severe. High frequency type ion plating is
It is considered that the substrate current is affected by applying a bias voltage structurally or changing the high frequency output. Therefore, the relationship between the high frequency output and the bias voltage and the current when depositing 80% gold alloy on the evaporation material was examined. FIG. 4 shows the results.

The bias current is increased by increasing the high frequency output (150 to 300 W) and the bias voltage (500 to 2000 V). From this result high frequency output,
It is considered that by increasing the bias voltage, the ionized particles are strongly struck on the substrate, and a more dense film is formed.

From the above results, increasing the bias voltage may make the film more dense, so the bias voltage was changed and the effect on the film was examined. That is, the bias voltage is changed from 1000 V to 2 under the above evaporation conditions.
The voltage was applied to 000 V to form a vapor deposited film for 13 minutes, and the spectral reflectance of the film was measured. The result is shown in FIG.

X: 1000V Y: 1500V Z: 2000V Although there is no change in the color tone by increasing the bias voltage in this way, the reflectance is improved and the vividness of the color is increased. (High-frequency output) Under the above evaporation conditions, a high-frequency output of 150
The spectral reflectance was measured for the coating film deposited for 13 minutes while changing the W and 250 W. The result is shown in Figure 6.
Shown in

A ₁ : 250 W A ₂ : 150 W By thus increasing the output to 250 W (A ₁ ), no change in the color tone of the purple film is observed, but the reflectance is 15
It was improved compared to 0 W (A ₂ ). (Formation of protective film) After the formation of the colored film is completed, aluminum is used as an evaporation material, and nitrogen gas (high purity 99.9999%) is used as a reaction gas for ionization by a reactive ion plating method. Aluminum nitride (A
A transparent protective film of 1N) was formed.

The conditions for forming the transparent protective film of aluminum nitride and the like are well known, and the description thereof will be omitted.

The noble metal jewelry with the purple film obtained in the above examples exhibited a vivid purple color, and almost no secular change such as fading was observed in the ordinary use. [Example 2] Under the above conditions for forming a colored film, nitrogen gas (high purity 99.9999) was used as a reaction gas for ionization.
%)It was used.

The spectral reflectance of the formed colored film was measured using a colorimeter of Kurabo Industries COLOR-710 (manufactured by Kurashiki Spinning Co., Ltd.).

When nitrogen gas is used for ionization during the formation of the colored film, it is considered that aluminum nitride is produced by the reaction between the evaporated aluminum and nitrogen gas. 8x there
Nitrogen gas of 10 ^-2 Pa was introduced, and high frequency output was 0, 15
An attempt was made to form a film by changing it to 0, 300, 400 W. FIG. 7 shows the spectral reflectance of the film at each output when the evaporation time was 13 minutes.

From the figure, the hue of the film obviously changes with the increase of the high frequency output, and the spectral reflectance is 5 at an output of 0W.
The purple film having absorption at 40 nm changed to a black film in the low wavelength region of 400 nm as the output increased. As a result of observing the surface of these coatings with an electron microscope, it was revealed that the porous coating became a smooth and dense coating by applying a high frequency. (Formation of protective film) After the formation of the colored film is completed, aluminum is used as an evaporation material, and oxygen gas is used as a reaction gas for ionization, and aluminum oxide (Al ₂ O ₃ ) is formed by a reactive ion plating method. Of the transparent protective film was formed.

The noble metal jewelry formed with the black film obtained in the above-mentioned examples exhibited a vivid black color, and almost no secular change such as fading was observed in the ordinary use.

[0033]

EFFECTS OF THE INVENTION Since the colored film-formed precious metal jewelry according to the present invention is configured as described above, the obtained colored film-formed precious metal jewelry exhibits vivid purple and black.
It has become possible to provide a new precious metal jewelry accessory.

Further, since the precious metal jewelry having the colored coating of the present invention is constructed as described above, it is possible to obtain a coating having practically sufficient durability. Moreover, the obtained film has a smooth and dense structure, and it is possible to obtain a product having excellent commercial value without defects such as rough skin and pinholes.

[Brief description of drawings]

FIG. 1 is a plan view showing an example of a precious metal accessory having a colored film which is to be obtained by the present invention.

FIG. 2 is a graph showing the results obtained by performing vapor deposition for 5 minutes and measuring the formed film by spectral reflectance and color coordinate.

FIG. 3 is a graph showing a result of measurement of a film formed by change with time using spectral reflectance and color coordinates.

FIG. 4 is a graph showing the results of examining the relationship between the high frequency output and the bias voltage and current when a gold 80% alloy was vapor-deposited on an evaporation material.

FIG. 5 is a graph showing the results of applying a bias voltage of 1000 V to 2000 V to form a vapor deposited coating for 13 minutes and measuring the spectral reflectance of the coating.

[Fig. 6] Changing the high frequency output to 150W and 250W,
It is a graph which shows the result of having measured the spectral reflectance about the film in vapor deposition for 13 minutes.

FIG. 7: Nitrogen gas was introduced, and high frequency output was 0, 150,
It is a graph which shows the result of having measured the spectral reflectance of the film which changed the 300 and 400W and tried film formation.

[Explanation of symbols]

 1 Ring 2 Light-colored part 3 Dark-colored part

Claims (3)

[Claims] 1. A noble metal accessory body, a colored film such as purple and black made of a gold aluminum alloy formed on the body of the precious metal accessory by an ion plating method, and an aluminum-based transparent protective film formed on the colored film. A precious metal jewelry that has a colored film that is characterized by having. 2. The precious metal jewelry with a colored coating according to claim 1, wherein the aluminum-based transparent protective film is aluminum nitride (AlN). 3. The noble metal accessory having a colored film according to claim 1, wherein the aluminum-based transparent protective film is aluminum oxide (Al ₂ O ₃ ).