JP2022145513A - Method of manufacturing watch decorative component, watch decorative component, and watch - Google Patents

Abstract

To prevent or suppress damage to a watch decorative component.SOLUTION: In a method of manufacturing a middle piece 12 having a decoration G on an upper surface of the middle piece 12, which decoration has projections and depressions 12d formed by a ditch K extending in a scanning direction of a pulsed laser beam, a surface 12b of a base material 12a of the middle piece 12 is covered with a hard film 12c made of a material harder than the base material 12a, and then a laser beam is applied to the hard film 12c to form the projections and depressions in such a manner that the base material 12a is not exposed also in the depressions.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a decorative part for a watch, a decorative part for a watch, and a watch.

For example, decorative parts such as wristwatch bands and dials are decorated. As an example of decoration, a large number of thin lines that form grooves are arranged at narrow intervals to form unevenness on the surface, and a pattern is formed by reflecting light.

Here, for example, it has been proposed to form the above-described unevenness by processing using a laser beam (laser processing). Specifically, the surface of the decorative part is irradiated with a laser beam to melt and sublimate the irradiated surface, and the laser beam is scanned to form grooves extending along the scanning direction. to form an uneven shape on the surface of the decorative part.

That is, the portion scanned with the laser light is recessed in a groove shape, and the portion where the groove is not formed becomes convex relative to the recessed groove, resulting in an uneven shape. Since the edge portion of the groove swells more than the portion where the groove is not formed, the swelled edge portion can be regarded as a convex and concave shape.

Here, a hard film (hard film) such as titanium nitride, titanium carbide, or diamond-like carbon (DLC) is formed on the surface of the decorative part. By forming a hard film, damage to the surface of the decorative part can be prevented or suppressed.

When the hard film is formed on the surface of the decorative part in this way, laser processing is performed after the hard film is formed (see, for example, Patent Document 1).

JP-A-5-287499

However, when the hard film is laser-processed, the hard film disappears from the portion scanned by the laser beam, exposing the base material of the decorative part (for example, stainless steel or titanium), which is softer than the hard film. The exposed portion has a problem that it has low wear resistance and is easily scratched.

The present invention has been made in view of the above circumstances, and provides a method for manufacturing a decorative part for a watch (a decorative part for a watch) that can prevent or suppress damage to the decorative part for a watch, a decorative part for a watch, and a method for producing the decorative part for the watch. The purpose is to provide a clock.

A first aspect of the present invention is a method for manufacturing a decorative watch part by irradiating a pulsed laser beam to form an uneven decoration on the surface of the decorative watch part, wherein the surface of the base material of the decorative watch part is A decorative component for a watch, which is coated with a hard film made of a material harder than the base material, and then does not expose the base material even in the concave portions of the unevenness when the hard film is irradiated with the laser beam to form unevenness. is a manufacturing method.

According to a second aspect of the present invention, the surface of a base material is covered with a hard film coated with a material harder than the base material, and the hard film is irradiated with a pulsed laser beam to form uneven decorations on the surface of the base material. In the decorative part for a watch, the base material is not exposed even in the recess.

A third aspect of the present invention is a timepiece having a decorative watch component according to the present invention.

According to the manufacturing method of the decorative watch part, the decorative watch part, and the watch according to the present invention, it is possible to prevent or suppress the damage of the decorative watch part.

1 is a perspective view showing a band of a wristwatch; FIG. FIG. 2 is a schematic diagram showing a state in which a decoration with grooves is formed on the upper surface, which is the surface of the middle piece that constitutes the band shown in FIG. 1 ; It is a photograph showing the details of the groove. FIG. 4 is a cross-sectional view of the middle piece taken along the line II of FIG. 3;

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method for manufacturing a decorative watch part, a decorative watch part, and a watch according to the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a band 1 of a wristwatch, and FIG. 2 is a schematic showing how a decoration G formed by grooves K is formed on the upper surface, which is the surface, of a middle piece 12 that constitutes the band 1 shown in FIG. It is a diagram.

The illustrated band 1 is worn by the user so that the longitudinal direction L extends along the circumferential direction of the wristwatch user's wrist. The band 1 has outer pieces 11 arranged at both ends in a width direction W perpendicular to the longitudinal direction L, and intermediate pieces 12 arranged between the ends of the outer pieces 11 .

The outer piece 11 has pieces 11a and 11b at both ends in the width direction W, respectively. These two pieces 11a and 11b are joined to rod-like members (not shown) extending in the width direction W to form an integral outer piece 11. As shown in FIG.

The middle piece 12 is arranged at a position shifted in the longitudinal direction L with respect to the outer piece 11, and is connected across the two outer pieces 11, 11 adjacent to each other along the longitudinal direction. The band 1 extending along the longitudinal direction L is formed by repeating the structure in which the outer piece 11 and the middle piece 12 are connected.

The outer piece 11 and the middle piece 12 are formed, for example, by covering a metal base material such as stainless steel with a hard film 12c. The base material of the outer piece 11 and the middle piece 12 is not limited to stainless steel, and may be other metal such as titanium. Also, the base material of the outer piece 11 and the middle piece 12 may not be metal such as stainless steel or titanium, and may be a material other than metal, such as resin. Note that the outer piece 11 and the middle piece 12 may be made of different base materials.

The middle piece 12 is an example of a decorative watch part to be decorated by the method of manufacturing a decorative watch part according to the present invention, and is also an example of a decorative watch part according to the present invention. A timepiece having this middle piece 12 is an example of the timepiece according to the present invention.

Specifically, as shown in FIG. 4, the middle piece 12 has a hard film 12c on a surface 12b of a base material 12a such as stainless steel or titanium, and the surface 12b is entirely covered with the hard film 12c. The hard film 12c is made of, for example, titanium carbide (3000 to 4000 HV hardness), titanium nitride (1900 to 2400 HV hardness), titanium nitrocarbide (2600 to 3200 HV hardness), or DLC (diamond-like carbon; 3000 to 5000 HV hardness). This film is made of a material harder than the material 12a (having a hardness of about 200 HV).

The hard film 12c is formed with a film thickness D0 of 1.0 [μm], for example. This film thickness D0 is at least 1.5 times thicker than the general film thickness of the hard film covering the middle piece 12, which is 0.6 [μm]. Considering productivity, the hard film 12c is formed with a thickness of about 1.0 [μm] to 2.0 [μm]. Also, the base material 12a (see FIG. 4) can be prevented from being exposed.

For example, when titanium nitride carbide is formed as the hard film 12c, the flow rate of argon gas is about 190 [cc/min], nitrogen gas is about 100 [cc/min], and methane gas is about 50 [cc/min]. After applying a cathode voltage of 10 [V] to the base material 12a, the evaporating material (titanium) set in the crucible is irradiated with an electron beam to evaporate, and the degree of vacuum is reduced to about 0.0. While maintaining the pressure at 2 [Pa], ion plating is performed for about 30 [minutes] to form a hard film 12c of titanium nitride carbide on the base material 12a. When forming titanium nitride as the hard film 12c, only nitrogen gas is introduced, and when forming titanium carbide, only methane gas is introduced.

When DLC (diamond-like carbon) is formed as the hard film 12c, for example, a hydrocarbon-based gas is introduced into the chamber in which the base material 12a is placed, and the film is formed by plasma CVD. The DLC may be formed by an ionization vapor deposition method, a sputtering method using a solid carbon target, an arc method, or the like.

In the hard film 12c, as shown in FIG. 2, a plurality of concave-convex grooves K extending along the longitudinal direction L of the band 1 are arranged to form decorations G. As shown in FIG.

FIG. 3 is a photograph showing a groove K formed by scanning a pulsed laser beam along the longitudinal direction L in the middle piece 12 covered with the hard film 12c, and FIG. 4 is a photograph showing II in FIG. FIG. 4 is a cross-sectional view showing a cross-section along a line;

The groove K extends in the scanning direction (longitudinal direction L) by scanning the hard film 12c of the middle piece 12 along the longitudinal direction L with a pulsed laser beam emitted from the laser head of the laser processing machine. formed by Specifically, since the hard film 12c of the middle piece 12 is intermittently irradiated with the pulsed laser light emitted from the laser head, the irradiated portion melts and sublimates into dots as shown in FIG. As shown in FIG. 4, a dot-like depressed portion 12d (concave portion) having a film thickness D1 smaller than the film thickness D0 of the portion 12f not irradiated with the laser beam is formed.

Then, the laser processing machine scans the laser head along the longitudinal direction L, so that the point-like recessed portions 12d are aligned in the longitudinal direction L, and the recessed portions 12d are aligned along the longitudinal direction L as a whole. groove K is formed. In the present embodiment, scanning is performed at such a speed that the dot-like recessed portions 12d are overlapped by about 1/4 of the diameter of the recessed portions 12d.

Here, the base material 12a is not exposed even in the recessed portion 12d. This is because the film thickness D0 of the hard film 12c is thicker than the film thickness of a general hard film, and therefore the processing conditions for laser processing for forming the grooves K in a hard film having a general film thickness are applied as they are. This is also because the laser beam does not reach the base material 12a, so that the recessed portion 12d is also covered with the hard film 12c (D1>0 [μm]).

On the other hand, the portion 12f, which is not irradiated with the laser beam, is relatively convex with respect to the concave portion 12d, and unevenness is formed. The edge portion forming the contour of the recessed portion 12d becomes a convex portion 12e that is more raised than the portion 12f that is not irradiated with the laser beam, and the film thickness D2 of this convex portion 12e is the same as that of the portion 12f that is not irradiated with the laser beam. It is thicker than the film thickness D0 (=1.0 [μm]) of the portion 12f where there is no film. Therefore, it can be considered that unevenness is formed by the concave portion 12d and the convex portion 12e.

Since the hard film 12c has a high melting point, when the hard film 12c is subjected to laser processing, the height difference (= D2-D1) becomes small, but from the viewpoint of obtaining sufficient visibility of the groove K formed as decoration, the difference between the film thickness D2 of the convex portion 12e of the middle piece 12 and the film thickness D1 of the recessed portion 12d is , 0.5 [μm] or more.

Specific conditions for forming the grooves K by laser processing include, for example, a YAG laser with a pulse period of 10 [μsec], an output of 10 [W], and a scanning speed of 2000 [mm/sec]. These conditions are only examples in this embodiment, and the method for manufacturing a decorative watch component according to the present invention may form grooves K under conditions other than these conditions.

According to the manufacturing method of the intermediate piece 12 of the present embodiment, the hard film 12c remains even in the recessed portion 12d of the manufactured intermediate piece 12 which has been subjected to laser processing, and the base material 12a is not exposed. Therefore, it is possible to prevent or suppress damage compared to the case where the base material 12a is exposed.

In addition, the unevenness formed on the intermediate piece 12 by the manufacturing method of the intermediate piece 12 of the present embodiment can suppress the swelling amount of the convex portion 12e to be lower than the general unevenness in which the base material 12a is exposed. As a tactile sensation when touching the unevenness, it is possible to prevent or suppress a feeling of being caught in resistance.

From the viewpoint of preventing catching on clothes, etc., the height difference between the convex portion 12e and the concave portion 12d of the middle piece 12, that is, the thickness D2 of the convex portion 12e and the thickness D1 of the concave portion 12d. The difference is preferably 3.0 [μm] or less. Therefore, the difference between the film thickness D2 of the convex portion 12e of the middle piece 12 and the film thickness D1 of the recessed portion 12d is more than 0.5 [μm] and less than 3.0 [μm]. preferable.

In the manufacturing method of the middle piece 12 of the present embodiment, the film thickness D0 of the hard film 12c is made thicker than the general film thickness, so that the base material 12a is not exposed even after the unevenness is processed by the laser beam. . However, instead of increasing the film thickness D0 of the hard film 12c, the base material 12a may not be exposed by changing the conditions for forming the grooves K by laser processing. In other words, the base material 12a may not be exposed by lowering the conditions for forming the grooves K by laser processing than general conditions.

As such processing conditions, for example, a YAG laser with a pulse period of 6 [μsec] and an output of 8 [W] is used, and grooves K are formed at a scanning speed of 2000 [mm/sec]. be able to. According to these processing conditions, even if the film thickness D0 of the hard film 12c is set to 0.6 [μm], which is a general film thickness, when the laser beam is irradiated to form the unevenness, the base material of the recessed portion of the unevenness is also reduced. The material 12a can be prevented from being exposed.

In the manufacturing method of the middle piece 12 of the present embodiment, the decoration G is formed by scanning the laser beam to form the linear groove K. Any method can be used as long as the surface of the decorative part is decorated with irregularities by irradiating a pulsed laser beam without scanning light, and the decoration is formed by irradiating a pulsed laser beam with dot-shaped irregularities. can be anything.

The above-described embodiment is used in a wristwatch band 1 as a decorative watch part to be decorated by the method for manufacturing a decorative watch part according to the present invention or as a decorative watch part according to the present invention. Although this is an example applied to a middle piece 12 with a ring, as a decorative watch part to be decorated by the method for manufacturing a decorative watch part according to the present invention, or as a decorative watch part according to the present invention, It is not limited to the middle pieces.

That is, as the decorative watch part to be decorated by the method for manufacturing the decorative watch part according to the present invention, or as the decorative watch part according to the present invention, even if it is an outer piece other than the middle piece, It is not limited to the band, and may be a watch decorative part other than the watch, such as a dial or a watch main body case (an exterior housing a dial, hands such as an hour hand, a movement, etc.).

Further, the decorative parts for watches to be decorated by the method for manufacturing decorative parts for watches according to the present invention are not limited to decorative parts for watches, and may be accessories for watches other than wristwatches. .

Note that the decorative component for a watch according to the present invention may constitute a part of a finished product, or may be a finished product. Moreover, the timepiece according to the present invention is not limited to a wristwatch, and may be a table clock, a wall clock, a decorated clock, or other clocks.

1 band 12 middle piece 12a base material 12b surface 12c hard film 12d recessed portion (recess)
12e Projection 12f Portions D0, D1, D2 Film thickness G Decoration K Groove L Longitudinal direction W Width direction

Claims (11)

In a method for manufacturing a decorative watch part, the surface of the decorative watch part is irradiated with a pulsed laser beam to form an uneven decoration,
coating the surface of the base material of the decorative part for a watch with a hard film made of a material harder than the base material;
After that, when the hard film is irradiated with the laser beam to form irregularities, the base material is not exposed even in the recesses of the irregularities. 2. The method of manufacturing a decorative part for a watch according to claim 1, wherein said hard film is formed with a thickness of 1.0 [[mu]m] or more and 2.0 [[mu]m] or less. 3. The method of manufacturing a decorative part for a watch according to claim 1, wherein the unevenness is formed with a height difference of 0.5 [[mu]m] or more. 4. The method of manufacturing a decorative part for a watch according to claim 1, wherein the unevenness is formed with a height difference of 3.0 [[mu]m] or less. 5. The method of manufacturing a decorative part for a watch according to claim 1, wherein the laser beam is scanned so that the unevenness extends in the scanning direction. Having a hard film coated with a material harder than the base material on the surface of the base material,
A concavo-convex decoration is formed on the hard film by irradiation with a pulsed laser beam,
A decorative component for a timepiece, wherein the base material is not exposed even in the recesses of the unevenness. 7. The decorative component for a watch according to claim 6, wherein said hard film has a thickness of 1.0 [[mu]m] or more and 2.0 [[mu]m] or less. 8. The decorative part for a watch according to claim 6, wherein the unevenness has a height difference of 0.5 [μm] or more. 9. The decorative component for a watch according to claim 6, wherein the unevenness has a height difference of 3.0 [[mu]m] or less. 10. The decorative component for a timepiece according to claim 6, wherein said unevenness extends in the scanning direction by scanning with said laser beam. A timepiece comprising the decorative watch component according to any one of claims 6 to 10.

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