JPS5853716B2 - Manufacturing method for exterior parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an exterior part for a wristwatch or the like having a black tone.

More specifically, the purpose is to obtain a highly decorative black film using a titanium ion plating method.

Conventionally, some exterior parts for wristwatches and the like are black in color.

This was done from a functional or decorative point of view, but in recent years, decorativeness has become an important element in the design of wristwatches, and the appearance of highly decorative black finishes that give a sense of luxury. desired.

Conventionally, the practical methods of black finishing include painting, black dyeing, black nickel plating, black chrome plating, and alumite.

However, the paint is easy to peel off and lacks a luxurious feel.
Black dyeing and black nickel plating have poor corrosion resistance and are prone to corrosion and discoloration; alumite is subject to limitations due to the use of aluminum; and black chrome plating is subject to limitations due to the use of chromic acid. None of the methods were practically satisfactory, as they had drawbacks such as the problem of pollution.

The present invention has been made to eliminate the above drawbacks.

That is, the present invention has succeeded in producing highly decorative exterior parts with an unprecedented black tone by ion plating titanium in a nitrogen gas atmosphere.

Next, an outline of the present invention will be explained with reference to FIG.

First, metal titanium is placed in the evaporation source 5, the object to be processed 3 is placed on the substrate that also serves as a cathode, and the substrate temperature is set at 100°C to 30°C.
00℃, and the inside of the vacuum chamber 1 is heated to lXl0 by the exhaust system 8.
After exhausting to around 'Torr, nitrogen gas is introduced through the gas inlet 6, and the gas pressure is adjusted to 1 x 10-3 to IXI 0-2.
Push to Torr.

Next, approximately 0.5 to 4 KV is applied by the DC applied voltage power supply 4, and the metallic titanium is evaporated by the electron beam generator 7.

By the above method, a black glossy film is formed on the surface of the object to be treated.

The relationship between the nitrogen gas pressure, the applied voltage, and the color of the produced film is as shown in FIG.

In Figure 2, A is a gray film forming area, B is a reddish black film forming area, C is a glossy black film forming area,
D is a matte black film forming area.

That is, a glossy black titanium film can be obtained only at C, where the nitrogen gas pressure is 10-3 to 1 O-2 Torr, the applied voltage is 0.5 to 4, and OKV.

The present invention will be described in detail below according to Examples.

Example 1 A wristwatch dial was manufactured from a brass plate, and the surface was polished to a mirror finish.

Next, a 1 micron bright nickel plating was applied to the sample.

The sample was mounted on a substrate that also served as a cathode, filled with argon gas, and bombarded with a gas pressure of 3 x 10'' Torr and an applied voltage of 2 KV, keeping the sample at 15Q°C for 10 minutes.
Did a minute of cleaning.

Next, stop introducing argon gas and introduce nitrogen gas,
Gas pressure was maintained at 8×10” Torr.

Then titanium was evaporated with an electron beam of 8KV and 350mA.
When a DC voltage of 2 KV was applied between the cathode and the evaporation source and ion plating was performed on the sample at 250°C for 10 minutes, a beautiful glossy black film was formed on the surface of the sample.

The dial plate obtained in this way was subjected to an adhesion test by bending it by 180 degrees, and it was found to be good.

Further, even when a constant temperature and humidity test at 49° C. and 98% was performed for 5 days, the moisture resistance was good.

Example 2 A wristwatch case was made using SuS316F and used as a sample.

The sample was bombarded (cleaned) in an argon atmosphere as in Example 1.

Next, introduce nitrogen gas and increase the gas pressure to 5X10-3 Torr.
was recommended.

After that, titanium was evaporated with an electron beam of 8KV and 300mA.
A DC voltage of 2 KV was applied between the cathode and the vapor deposition source, the sample was kept at 200° C. while rotating, and ion plating was performed for 10 minutes, and a glossy black film was formed on the sample surface.

When the case thus obtained was subjected to a 48-hour immersion test in artificial sweat, no corrosion was observed and the result was good.

Good results were also obtained in the adhesion test of heating and quenching at 250°C.

In addition, better results than black chrome plating were obtained in the abrasion resistance test on a cloth buff.

Example 3 A wrist watch band manufactured using SuS316F was used as a sample.

The sample was bombarded in an argon gas atmosphere as in Example 1 to clean the sample surface.

Next, introduce nitrogen gas and increase the gas pressure to 8X10-3 Torr.
was recommended.

Titanium was evaporated with electron beam & KV, -25 mA,
A DC voltage of IKV was applied between the cathode and the evaporation source, and while the sample was being rotated, ion blating was performed for 15 minutes while keeping the sample at 150°C. A glossy black film was obtained on the sample surface.

When the band thus obtained was subjected to the same tests as in Example 2, good results were obtained in all tests.

As described in the above embodiments, the nitrogen gas pressure was 10”-
10-2 Torr, applied voltage 0.5-4. By ion-blating titanium under OKV conditions, a titanium film with a black tone is obtained instead of the conventionally obtained gold-colored titanium nitride, and a black finish with unprecedented decorativeness and excellent adhesion is obtained. This has the effect that it is possible to provide an exterior part for a wristwatch having the following characteristics.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing the ion blating apparatus, and FIG. 2 is a diagram showing the relationship between nitrogen gas pressure, applied voltage, and color of the produced film. 1... Vacuum chamber, 2... Cathode, 3.
...Processed object, 4...DC applied voltage source,
5... Vapor deposition source, 6... Gas inlet, 7
...Electron beam generator, 8...Exhaust system.

Claims (1)

[Claims] 1 Using titanium as the evaporation source, lXl0' ~ 1x1O-
In a nitrogen gas atmosphere of 2 Torr, 0.5
A method for manufacturing an exterior component, comprising forming a black film by applying a high voltage of ~4KvO and performing ion plating.