JPS5948675A - Multi-color case of watch - Google Patents

Abstract

PURPOSE:To obtain an inexpensive multi-color case having stable quality, by a method wherein a laminate material formed by cladding two or more metals is processed into a case configuration and, thereafter, said metals are colored by a heat treatment method. CONSTITUTION:As a laminated material, a laminated clad material coil C is formed by a method wherein, for example. Ti, Au, Ag and SUS are used and, for example, after a pure Ti material coil A and a SUS304 coil B are washed in a washing tank 2 and oxide films on the coils A, B are removed by a means 2, both treated coils are alternately arranged to be subjected to cold bonding and the bonded one is subjected to diffusion heating in a furnace 4. A case is formed by using the plate formed by obliquely cutting the coil C as shown by lines (a) and, when said case is treated at 900 deg.C for 3hr in high purity N2 gas, the Ti material A is turned to a golden color and the SUS304 material B is slightly discolored. In the next step, grinding processing is performed to obtain a two-color case comprising the white SUS304 material A and the golden color Ti material A is obtained. As mentioned above, by using corrosion resistant metals, a multi-color case having stable quality is obtained. Various color tones are obtained by a heat treatment condition and the combination of metals.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multicolored case for a watch that has two or more color tones and has excellent corrosion resistance.

Conventional watch cases include 5US304 and 5US31.
Stainless steel such as 6L, brass with decorative plating, cemented carbide for scratch-resistant bodies, and precious metals are used for some purposes. However, due to the diversification of designs and consumer preferences, multicolored cases are required.

Methods for manufacturing multicolored cases include methods such as plating, sputtering, and ion blasting to obtain partially different color tones; Partial plating on stainless steel results in unstable quality and high cost. In other words, stainless steel forms a stable passive film on its surface and therefore has excellent corrosion resistance, but destroying this passive film and performing partial plating requires a complicated process and high cost. It has many drawbacks, such as requiring expensive equipment, causing poor adhesion and rust, and being expensive with current technology.

On the other hand, so-called dry plating methods, such as ion blasting and sputtering, require complicated processes such as pre-treatment of the object to be treated and masking, and long dry plating times, resulting in many uneconomical aspects including materials. In addition, the current technology has the drawbacks of easily causing quality defects, being unsuitable for continuous production, and being expensive. By laminating different raw materials and coloring one or more of them by heat treatment such as nitriding, a multi-colored case with stable quality and low cost is provided. The present invention will be explained below based on examples.

Example 1 FIG. 1 is an example of a laminated cladding process used in the present invention. Pure Ti of B is placed between the three 5US3D4 materials of A.
A laminated clad material of C was created by cladding the material. That is, completely pretreated pure Ti material 2
Prepare 3 coils of 304 material, wash A's 5US304 in washing tank 1, remove the oxide film in step 2, and then
The US3D4 material and the pure T1 material B were arranged alternately, cold bonded using 31 rolls, and diffusion heated using a 4 furnace body to produce a 0 laminated clad material.

Next, as shown in FIG. 2, the laminated clad material obtained in step 0 was cut diagonally and cut into individual plates G, and then a watch case shown in FIG. 3 was produced.

Next, coloring treatment was performed under the following conditions.

Processing conditions Temperature: 900℃±5℃ Holding time: 3 hours Atmosphere: High purity N, gas In this treatment, the pure T1 material of B is colored gold, and the 5U of A is
S304 was slightly discolored.

Next, a polishing process was performed to complete a sample having two colors: glossy white of 5US304 and gold of pure T1 material.

Table 1 shows the results of corrosion resistance tests of samples of the present invention and conventional watch cases. Note that the sample used for comparison with the present invention was prepared by a conventional method.

Furthermore, the results of the corrosion resistance test were comprehensively judged by conducting an artificial sweat resistance test, a seawater resistance test, and a salt spray test, all of which are required for exterior parts for portable watches.

Table 1: In the conventionally used methods, corrosion resistance was poor in all cases, and even in the case of 5US304, which was the best and was partially subjected to sputtering treatment, slight discoloration occurred, which was the same level as in the non-polishing state of the present invention. Therefore, the polished sample of the present invention was very good, and no corrosion occurred even in a three-year portable test conducted separately.

In the present invention, we limited the materials by combining SUS material, which is a white metal with excellent corrosion resistance, colored metals such as Au, and metals such as T1 that can be colored by heat treatment.
This is because it is possible to produce a wide variety of colors.

The above examples form a part of the present invention, and the nitriding treatment of pure T1 can be performed by changing the treatment temperature from 900 to 1200°C and the time from 1 hour to 12 hours to obtain a golden to ocher color tone. It is easy to agree that the polishing method is more flexible due to the change in the thickness of the nitrided layer (colored part), and that the surface layer has a satin finish or ceramic appearance, making it possible to create a versatile design.

As detailed above, according to the present invention, by changing the combination of various materials and heat treatment conditions, the thickness ratio of each material, the order of combination, the direction of material removal during case processing, etc.
It has high corrosion resistance and is inexpensive.

It is possible to provide a multicolored watch case that allows for a variety of designs.

[Brief explanation of the drawing]

FIG. 1 shows the cladding process of one embodiment, A...
SUS material, B...°・T1 material, 0... Laminated material, 1... Cleaning, 2... Oxide film removal,
3... Adhesion rolling, 4... Diffusion heat treatment Figure 2 is an explanatory diagram of the processing method for laminated materials.
Cutting directions, Figures 3 (a) and (b) are for an example multicolored case (a).
. . . The color tone is changed in the longitudinal direction and (h) . . . in the circumferential direction. Applicant Daini Seikosha Co., Ltd. Agent Patent Attorney Mogami 429- α Co Ill Procedural Amendment (Method) February 18, 1981 2, Title of Invention Multicolor Watch Case 3 Case of Person Who Makes Amendment 0 relationship 6-31-1, Kameido, Koto-ku, Tokyo
Person (232) Daini Seikosha Co., Ltd. Representative Director Hattori - Department 4, Agent 5, Date of amendment order January 25, 1980 6, Specification subject to amendment 2 Contents of amendment (1) Drawings The brief explanation section has been revised as follows. -dself- Brief Description of the Drawings FIG. 1 is a diagram showing an embodiment of the laminated cladding process in the present invention. FIG. 2 is an explanatory diagram of a method of processing a laminated material. Third
Figures (a) and (b) are plan views of the multicolor case of the present invention. A...EIUEI material B...T
i Material C...Laminated material 1...Cleaning 2...Oxide film removal 6...Adhesion rolling 4...Diffusion heat treatment and above

Claims (2)

[Claims] (1) A watch characterized by having two or more different color tones obtained by processing a laminated material clad with two or more different metals into a desired case shape and then coloring the one or more metals using a heat treatment method. Multicolor case. (2) A multicolored case for a watch according to claim (1), characterized in that the laminated material includes one of Ti, Au, Ag, and SUS.