JPH0725199A - Noble metal decorating method for sapphire - Google Patents

Abstract

PURPOSE:To mold a noble metal decorating component such as or a sapphire having a stereoscopic appearance by melting gold alloy having a low melting point in a recess, and protruding it in a protruding state while fusion-bonding it to a metallized surface of the groove. CONSTITUTION:After a groove 2 is formed on a surface of a sapphire base 1 by ultrasonic processing, an Mo-Mn layer 3 is baked on an inner surface of the groove, an Ni-Au-plated layer 4 is further provided to form a metallized layer, and an unnecessary part of an upper surface of the sapphire except the inner surface of the groove is removed by deleting. Then, after gold and tin solder 5 is filled in the metallized groove 2, it is heated to be melted. Thereafter, a stereoscopic decoration matched to a pattern shape raised with a protruding shape is obtained. Further, the surface of the protruding gold alloy is plated, buffed and an electrolessly 18K-plated layer 6 is provided. Then, it is again buffed, thereby obtaining a sapphire component having a sense of stereoscope.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timepiece exterior component. More particularly, it relates to a method for decorating a sapphire cover glass for a watch and a ceramic material for decoration with a noble metal.

[0002]

2. Description of the Related Art Conventionally, as a decoration technique of this kind using a sapphire cover glass for a watch as a base, a decorative component made of a precious metal or a ring-shaped decorative component made by plating a BS material with a cover glass is used. Directly on the surface
A method of adhering and fixing using an organic adhesive has been adopted. However, organic adhesives are easily affected by external environmental changes such as sweating, heat, and ultraviolet rays after adhesive fixation, which may lead to a serious defect such as the removal of decorative parts due to aging, which is a major problem in terms of durability and reliability. Becomes

In addition, a technique has been used in which the surface of the cover glass is grooved and metallized, and a low-temperature brazing material is used to fix it to the precious metal, which is a decorative member, by brazing. There are restrictions on the materials that can be combined depending on the difference in the coefficient of thermal expansion, the shape of the decorative parts to be fixed, the joint area, the dimension settings of the brazing auxiliary parts, etc. In addition to the problem that the degree of freedom in shape is low, the problem of structural cracking of the sapphire substrate greatly affects the final yield, which is a major factor in the high cost.

For this reason, the development of a technique for directly decorating a noble metal member in a free shape and easily on the exterior surface of a sapphire cover glass, decorative ceramics or the like without using an adhesive fixing or brazing joining technique has been developed. Was wanted.

[0005]

In order to solve the problems of the prior art, the present invention performs groove processing of a desired decorative pattern shape on the surface of a sapphire or ceramic substrate by an ultrasonic processing method or the like, and the groove portion thereof is formed. Using a metallization method such as sputtering, a metallized layer that does not deteriorate even in the high temperature range where brazing is performed and that has good adhesion to sapphire and ceramics is formed. Pour it in and pour it up according to the decorative pattern.

The low melting point gold alloy contained in the groove does not rest on the surface of the base material other than the groove having poor surface wettability when melted by heating, and concentrates on the metallized surface inside the groove having good wettability. The gold alloy thus collected and thus melted is in a raised state due to the surface tension and hardens as a decorative member according to the groove pattern. If gloss or color adjustment is required to improve decorativeness, thick plating of Au is applied, and then final finishing such as buffing is performed to create a gloss that matches the groove pattern without damaging the substrate surface. A three-dimensional precious metal decorative component can be obtained.

[0007]

Embodiment 1 FIG. 1 is a side sectional view of each step showing an embodiment of the present invention. After forming a groove 2 of 0.5 mm on the surface of the sapphire substrate 1 by ultrasonic processing (a), a Mo-Mn layer 3 is formed on the inner surface of the groove by using a Mo-Mn paste-like ink by baking treatment, and further decorated. Ni-Au plating layer 4 is applied to improve the adhesion with the gold alloy, and a metallized layer of about 0.1 mm is formed (b). Next, unnecessary portions of the sapphire upper surface other than the groove inner surface were removed by grinding on the same surface, and the surface was polished (c).

Next, a low melting point paste-like gold-tin (Au80 / Sn20) solder material 5 is filled in the inside of the metallized groove and heated to about 350 ° C. in the atmosphere using an electric heater to heat the gold-tin solder. Material 5 was melted. Due to the effect of surface tension, the molten gold alloy bulged into a convex shape on the surface of the sapphire substrate, and three-dimensional decoration according to the grooved pattern was obtained (d).

Further, the obtained convex gold alloy surface is subjected to buffing treatment as a plating undercoat treatment, and the surface roughness of the surface is made finer and polished carefully until a gloss is obtained.
After the K plating layer 6 was applied to a thickness of about 6 μm, the final buffing was performed again to finish the sapphire substrate and the ridge line of the plating portion (e). By these processing treatments, it is possible to give a three-dimensional convex pattern on the surface of the transparent sapphire substrate, which has a golden color unique to glossy precious metals, and the decorative portion is
We were able to obtain a sapphire part with a three-dimensional effect filled with a gold alloy of 18K or higher.

[0010]

Second Embodiment FIG. 2 is a top view of another example of the present invention.
The upper surface of the sapphire cover glass for a watch was subjected to ultrasonic groove processing in a time-character pattern, and then the same processing steps as in Example 1 were performed. In the figure, the shaded area 7 indicates the decorative part, and the time-like pattern of the flat dial that is normally seen through the transparent sapphire cover glass appears as if it were raised above the sapphire surface, and the three-dimensional gold color peculiar to precious metals is also present. As a sapphire cover glass part for jewelry watches, which is capable of producing a luster and has a high-class feeling, a product with a satisfactory texture and finish was obtained.

[0011]

Example 3 Similarly, decorative black zirconia ceramics used for cuffs, tie pins and the like were treated with a family crest pattern in the same process as in Example 1. The completed cuffs and tie pins consisted of two-tone colors, black of zirconia ceramics and gold of the decorative part, and became a three-dimensional decorative component with dignity, and the texture and finish were full of luxury.

[0012]

As described above in detail, according to the present invention, a sapphire or ceramic substrate is subjected to a groove processing of a decorative pattern shape by an ultrasonic processing method or the like, and the groove portion is subjected to a metallizing method such as sputtering or baking. By forming a metallized layer that does not deteriorate even in a high temperature range and has good adhesion, and pouring a low melting point gold alloy that has been heated and melted into the groove, and hardening it in a state where it rises due to surface tension, the part that follows the groove pattern It becomes a decorative shape. Further, thick plating of Au or the like is applied for gloss and color tone adjustment, and buffing is performed for final finishing to obtain a sapphire and a precious metal decorative component such as ceramics having a three-dimensional effect.

According to the present invention, the conventional fixing method using an adhesive or brazing is unnecessary, and the difference in the coefficient of thermal expansion, which is a problem in the brazing process of the ceramic material and the noble metal, particularly at the time of joining. The sapphire substrate did not crack, and the fixing strength of the decorative component could be sufficiently maintained in terms of structure.

Further, since there is no restriction on the shape of the decorative parts, the joint area, and the dimension setting of the brazing auxiliary parts, and further, the precise molding load of these decorative parts in the prior art is not required at all, the time character of the timepiece parts Even complicated patterns such as patterns can be easily formed, and the degree of freedom in design is dramatically increased. Also, with this method, heat treatment can be performed without using the brazing setting jig for the decorative member, which was required in the conventional brazing process, so the work process can be simplified, mass productivity can be improved, and cost can be reduced. did it.

[Brief description of drawings]

FIG. 1 is a side sectional view of each processing step in the present invention.

FIG. 2 is a pattern diagram showing an upper hour-shaped pattern of the sapphire cover glass for a timepiece of the present invention.

[Explanation of symbols]

 1 Sapphire substrate 2 Groove 3 Mo-Mn layer 4 Ni-Au plating layer 5 Gold-tin solder material 6 18K plating layer 7 Decorative part

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location C23C 14/58 8520-4K (72) Inventor Yoichi Yaguchi 3-8-22 Nitta, Adachi-ku, Tokyo Namiki Seiki Mitsuge Co., Ltd.

Claims (3)

[Claims] 1. A sapphire substrate is subjected to a groove processing of a decorative pattern by an ultrasonic method or the like, and Mo-Mn and N are formed on the inner surface of the groove.
After forming the i-Au metallization layer, a low melting point gold alloy is melted in the groove recesses, and the metallization surface inside the groove is welded to form a convex buildup, and the same three-dimensional partial decoration as the groove pattern is applied. A method for decorating a sapphire with a precious metal, which is characterized by obtaining a shape. 2. The precious metal decorating method according to claim 1, wherein the base is made of decorative ceramics. 3. The decorative metal melted in the groove of the base is Au-Sn.
The precious metal decoration method according to claim 1, which is a low melting point gold alloy.