JPS63213655A - Personal ornaments - Google Patents

Abstract

PURPOSE:To prevent the tarnish of personal ornaments by the air, sweat, etc., by forming a protective film of a specified metal on the surface of each of the personal ornaments made of a tarnishable metal such as Ag or Cu and by further forming a film of a specified compd. by PVD or other method. CONSTITUTION:Personal ornaments 1 such as watchcases, bands, rings or necklaces made of a metal which tarnishes readily in the air by a reaction such as oxidation or sulfurization, e.g. Ag or Cu are successively subjected to ultrasonic cleaning with trichoroethylene and to bombard in a gaseous Ar atmosphere. A protective film 2 of a metal such as Si, In, Sn or Ti is then formed on each of the personal ornaments 1 to 10-500Angstrom thickness and a film 3 of a compd. such as SiO2, In2O3, Al2O3, SnO2, TiO2, TiC or TiN is formed on the film 2. The tarnish of the personal ornaments made of Ag or Cu by oxygen, hydrogen sulfide, etc., in the air is prevented.

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to accessories such as watches (sides), bands, rings, necklaces, etc. made of metals that easily discolor, such as silver and copper, or alloys containing them. In particular, it relates to jewelry having a protective coating on its surface.

(Prior art) Jewelry made of silver or copper is often used as jewelry because of its whiteness or redness, which is not found in other metals. causes discoloration. Therefore, it is customary to put an organic clear coat on the surface, or to plate silver products with rhodium before putting them on the market. However, clear coats destroy the original texture of the product, and rhodium-plated products have the problem of losing the original whiteness of silver. For this reason, research has been carried out on coating transparent films using vapor deposition, ion blating, etc., but the surface tends to discolor due to oxygen gas, causing loss of gloss or discoloration, and there is no known product that satisfies the requirements.

(Technical Problem) The present invention provides a solution to the above-mentioned problem, and its purpose is to provide a coating on the surface of a metal that is prone to discoloration, which can preserve the luster and texture of the background, so that it does not discolor during use. The aim is to provide accessories.

The present invention, which achieves the above object, is an accessory having a compound coating on a metal surface, in which a protective coating made of a single element that preserves the metal surface is provided between the metal surface and the compound coating. be. The compound coating is 5i02, In2O
3, AI 2O3, Sn O2N T I O2, Ti
An inorganic coating of N, r; c is suitable in terms of durability, hardness, texture, etc., and TaC or CrN can also be used.

On the other hand, the undercoat or protective coating is 3i, In,
Al, Sn, Ti, etc. can be used. Also Cr, N r,
Co, Ta, Pd, Au, and Zr can also be used.

It is necessary to set the thickness of the undercoat appropriately, and research has confirmed that the thickness range is preferably from 10 Å to 500 Å. If the film thickness is too thick than 10 mm, the effect will be weak and the base material will change color when gas is introduced in the next process, and if it is too thick than 500 mm, the original color tone of the base material will change.

This protective coating can be formed by a PVD method.

In forming the film, the surface of the jewelry body is degreased, washed, and dried, and after these steps, it is placed in a vacuum device and evacuated. After cleaning again by bombarding with argon or other inert gas, a protective film made of the above-mentioned single element is deposited under a vacuum of 10 -3 to 10' Torr, and then a compound film is formed.

(Operations and Effects of the Invention) The present invention is constructed as follows, so that the surface of the accessory main body 1 is first undercoated with a protective coating 2;
Furthermore, the structure is covered with a compound film 3. This protective coating 2 is made of a single element and has a necessary and sufficient thickness of 108 to 500, so it completely shields the metal surface from the external environment, and also has good and stable adhesion to the metal surface and the compound coating. . Therefore, the luster of the base metals such as silver and copper remains as is, and the coating 3 is made of silver, copper and other easily discolored metals.
Since it is sufficiently hard compared to the alloy, it prevents scratches and does not discolor due to air, sweat, etc. during use.

(Example) Examples will be described below. However, the present invention is not limited thereto.

(1) Ultrasonically clean the silver ring with Triclean for 10 minutes, evacuate it in a vacuum chamber, and then bombard it in an argon atmosphere for 15 minutes at a substrate voltage of 500 V and a substrate heating temperature of 250°C.
After that, Ti was vaporized for 100 minutes under conditions of a substrate voltage of 300 V and an ionization voltage of 45 V, and a 5iOz film was formed to a thickness of 2 μm. This product retains the luster of the silver base material, and no discoloration was observed even in a 24-hour artificial sweat test.

(2) After electrolytically degreasing the brass watch side with copper plating of 10 μm, dry it with fluorinated hydrocarbon (trade name Freon), evacuate it in a vacuum chamber, and then apply argon at a substrate voltage of 300 V and a substrate heating temperature of 250°C. Perform bombardment for 10 minutes,
Under the conditions of a low substrate voltage of 2O0V and an ionization voltage of 50V, 50 layers of A1 were undercoated to form a rough Δ12O3 film with a thickness of 1 μm. The copper side of this watch retained its red color and luster and was exposed to the atmosphere for 60 days without any discoloration.

FIG. 1 shows the ring of Example 1, FIG. 2 shows a partially enlarged view thereof, and FIG. 3 shows a partial cross-section of the ring according to the example 1. .

In each figure, 1 is a silver ring body, 2 is a protective coating, 3 is a compound coating, 4 is a brass body, and 5 is a copper plating layer as a fully curved surface that is easily discolored. Note that the effect as a protective coating has been confirmed for 10 types of single elements other than A1 and T1, and the same is true for the remaining 7 types of compound coatings.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an accessory according to the present invention, in which Fig. 1 is a partially cutaway side view of a ring, Fig. 2 is a partially enlarged sectional view thereof, and Fig. 3 is a sectional view of the watch side. It is. Figure 1 Figure 3 Figure 42

Claims (4)

[Claims] (1) In accessories having a compound coating on the metal surface,
An accessory comprising a protective coating made of a simple element that preserves the metal surface between the metal surface and the compound coating. (2) The accessory according to claim 1, wherein the metal surface is easily discolored by oxidation, sulfurization, etc. because it contains silver, copper, or these. (3) Compound film is SiO_2, In_2O_3, Al
_2O_3, SnO_2, TiO_2, TiN, TiC
The accessory according to claim 1 or 2, wherein the protective coating is made of Si, In, Al, Sn, or Ti. (4) The accessory according to any one of claims 1 to 3, wherein the compound coating has a thickness of 10 Å to 500 Å.