Watch parts, watches and methods for manufacturing watch parts

Abstract

To provide a manufacturing method for applying glossiness to a surface with low glossiness to realize the appearance with designability.SOLUTION: A method for manufacturing a watch component includes the steps of: irradiating a surface of a support plate 5 with a femtosecond laser 28 to form a first processed surface 12 having a predetermined pattern; and irradiating at least part of the first processed surface 12 with a nanosecond laser 39 to form a second processed surface 14 having a surface roughness smaller than the first processed surface 12 and having an oxide film 42 thicker than the first processed surface 12.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a timepiece component, a timepiece, and a method for manufacturing a timepiece component. [Background technology]

[0002] Clock parts are used in which patterns such as letters and marks are formed by irradiating a metal surface with a laser. In Patent Document 1, a femtosecond laser is used as the laser. By irradiating the clock part with a femtosecond laser, an ablation process is performed in which solids on the metal surface are instantaneously vaporized and dispersed. A surface with high surface roughness and low gloss is formed by the ablation process. Grooves with low gloss at the bottom are formed in the places irradiated with the femtosecond laser. Patterns such as designs, letters, marks, etc. are formed in the clock part with these grooves. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-20378 A Summary of the Invention [Problem to be solved by the invention]

[0004] Since the processing of Patent Document 1 uses a femtosecond laser, a surface with low glossiness is formed at the bottom of the groove on the watch part. In processing watch parts, there are cases where it is desired to give gloss to the fine cut surface formed by femtosecond laser processing, and in such cases, it is necessary to provide a process separate from the femtosecond laser processing. However, it is difficult to provide gloss processing to the delicate cut surface formed by the femtosecond laser, and providing a separate process may also reduce productivity. Therefore, a manufacturing method that gives gloss to any part of the surface processed by the femtosecond laser to create an appearance with design has been desired. [Means for solving the problem]

[0005] A method for manufacturing a watch component includes the steps of: forming a first processed surface having a predetermined pattern by irradiating a surface of a metal component with a first laser having a pulse width of femtoseconds; and forming a second processed surface having a smaller surface roughness than the first processed surface and a thicker oxide film than the first processed surface by irradiating at least a portion of the first processed surface with a second laser having a pulse width of femtoseconds or longer.

[0006] The watch component has a metal substrate and a predetermined pattern formed by irradiating the substrate with a first laser having a femtosecond pulse width, and comprises a first machined surface having a first surface roughness, and a second machined surface having a second surface roughness smaller than the first surface roughness, formed by irradiating the first machined surface with a second laser having a pulse width of femtoseconds or more, wherein the second machined surface covers at least a portion of the first machined surface, and the second surface roughness is 0.1 μm or more and 0.3 μm or less.

[0007] The watch comprises the watch parts described above. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a rear view of the timepiece according to the first embodiment. [Diagram 2] FIG. 4 is a diagram showing a measurement example of the surface shape of a first processed surface. [Diagram 3] FIG. 4 is a diagram showing a measurement example of the surface shape of a second processed surface. [Figure 4] 1 is a flow chart of a laser decoration method. [Diagram 5] FIG. 4 is a schematic diagram for explaining a first processing step. [Figure 6] FIG. 4 is a schematic diagram for explaining a first processing step. [Figure 7] FIG. 4 is a schematic diagram for explaining a first processing step. [Figure 8] FIG. 4 is a schematic diagram for explaining a second processing step. [Figure 9] FIG. 4 is a schematic diagram for explaining a second processing step. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. 11 is a rear view of a timepiece according to a second embodiment. [Figure 13] FIG. 11 is a diagram for explaining the relationship between the thickness and color of an oxide film according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First embodiment In Fig. 1, the watch 1 of this embodiment is a three-hand analog wristwatch. Fig. 1 is a view of the watch 1 from the back side. The watch 1 is not limited to an analog watch, and may be any watch that has metal parts, such as a digital watch, a combination watch, a smart watch, or a health watch.

[0010] Watch 1 is a wristwatch with a see-through back. A transparent back cover 3 is attached to body 2, allowing the internal mechanism to be observed. Body 2 functions as a case. Body 2 is made of a hard metal such as titanium or stainless steel. Body 2 is roughly circular. Back cover 3 is fitted onto the inner circumference of the ring-shaped wall of body 2. Back cover 3 is made of sapphire glass.

[0011] A movement 4 for driving the hands is housed inside the case 2. In FIG. 1, the timepiece parts of the movement 4 and a metal part, a receiving plate 5, can be observed through the back cover 3. The receiving plate 5 has a metal base material 6. A plurality of gear bearings 7 are provided on the base material 6. The base material 6 is made of titanium, a titanium alloy, or stainless steel. Other metals such as nickel silver, brass, duralumin, and alloys containing iron may also be used as the material for the base material 6.

[0012] The substrate 6 has a first region 8, a second region 9, and a third region 11. The surface of the substrate 6 in the first region 8 is a first processed surface 12. The shapes of the first region 8 and the first processed surface 12 are a first pattern 13. In other words, the first processed surface 12 has the first pattern 13. The surface roughness of the first processed surface 12 is a first surface roughness. The first processed surface 12 and the first pattern 13 are formed by irradiating the substrate 6 with a first laser having a femtosecond pulse width. The first laser is, for example, a femtosecond laser, and the pulse width is preferably in the range of 100 fs to 900 fs.

[0013] The surface of the substrate 6 in the second region 9 is the second processed surface 14. The second processed surface 14 in the second region 9 is composed of four parts. The shapes of the four parts are a second pattern 15 as a pattern, a third pattern 16 as a pattern, a fourth pattern 17 as a pattern, and a fifth pattern 18 as a pattern. The surface roughness of the second processed surface 14 is the second surface roughness. The second surface roughness is smaller than the first surface roughness. The second processed surface 14 is formed by irradiating the first processed surface 12 with a second laser having a pulse width of femtoseconds or more. Therefore, the second processed surface 14 is a surface that covers a part of the first processed surface 12. In this embodiment, the first processed surface 12 has the first pattern 13 and the second pattern 15 to the fifth pattern 18. The second processed surface 14 has the second pattern 15 to the fifth pattern 18.

[0014] The surface roughness of the first machined surface 12 is the first surface roughness. The surface roughness of the second machined surface 14 is the second surface roughness. The surface roughness is based on the surface shape of the surface to be measured. The surface roughness is the arithmetic mean roughness Sa. The first surface roughness and the second surface roughness are measured with a shape analysis laser microscope. The shape analysis laser microscope is a VK-X250 (registered trademark) manufactured by Keyence Corporation. The magnification of the shape analysis laser microscope during measurement is 150x.

[0015] The surface of the substrate 6 in the third region 11 is an unprocessed surface 19. The unprocessed surface 19 in the third region 11 is made up of four parts. The shapes of the four parts are a sixth pattern 21, a seventh pattern 22, an eighth pattern 23, and a ninth pattern 24. The unprocessed surface 19 is a surface that is not irradiated with either the femtosecond laser or the second laser.

[0016] Figures 2 and 3 are examples of roughness curves in line roughness measurements where the surface roughness is measured along a specified line. The horizontal axis indicates the measurement position where the surface roughness was measured. More specifically, it is shown as the distance from the measurement start point. The vertical axis indicates the position of the surface shape in the thickness direction of the substrate 6. The average position of the measurement results is set to 0. The + direction is the direction in which the surface shape protrudes, and the - direction is the direction in which the surface shape is recessed.

[0017] As shown in FIG. 2, in the example of the surface shape of the first processed surface 12, the surface irregularities vary between −0.897 μm and +0.897 μm.

[0018] 3, in an example of the surface shape of the second machined surface 14, the surface unevenness varies between −0.295 μm and +0.295 μm. The second machined surface 14 has a smaller surface roughness than the first machined surface 12.

[0019] Surface roughness is a surface roughness measurement, which is a two-dimensional extension of line roughness measurement. As with line roughness measurement, in surface roughness measurement, the second machined surface 14 has a smaller surface roughness than the first machined surface 12. Therefore, the second surface roughness is smaller than the first surface roughness. The second surface roughness is preferably 0.1 μm or more and 0.3 μm or less.

[0020] According to this configuration, the surface of the base material 6 comprises a first processed surface 12 and a second processed surface 14. The first processed surface 12 has a greater surface roughness than the second processed surface 14, and is therefore a so-called matte surface with a low gloss. The glossiness is measured with a glossmeter. The second processed surface 14 has a smaller surface roughness than the first processed surface 12, and is therefore a surface with a high gloss. Because the surface of the base material 6 comprises the first processed surface 12 with a low glossiness and the second processed surface 14 with a high glossiness, the surface of the base material 6 can be given a more designed appearance than when it is composed only of the first processed surface 12 with a low glossiness.

[0021] Next, a method for manufacturing the first processed surface 12 and the second processed surface 14 of the above-mentioned backing plate 5 will be described. In the flow chart of Fig. 4, step S1 is a first processing step. In this step, the first processed surface 12 having the first pattern 13 and the second pattern 15 to the fifth pattern 18 is formed by irradiating the surface of the base material 6 of the backing plate 5 with a femtosecond laser. Next, the process proceeds to step S2.

[0022] Step S2 is the second processing step. In this step, a second laser having a pulse width of femtoseconds or more is irradiated onto a part of the first processed surface 12 to form a second processed surface 14 having a smaller surface roughness than the first processed surface 12 and a thicker oxide film than the first processed surface 12. The first processed surface 12 and the second processed surface 14 are completed by the above steps. Here, the pulse width of femtoseconds or more is preferably, for example, 100 fs or more, and more preferably 1 ns or more and 200 ns or less.

[0023] Next, the manufacturing method will be described in detail in accordance with the steps shown in FIG. 5 to 7 are diagrams corresponding to the first processing step of step S1. As shown in FIG. 5, a laser processing device 25 is prepared. The laser processing device 25 includes a first laser light source 26 and a second laser light source 27. The first laser light source 26 is a light source that emits a femtosecond laser 28. The second laser light source 27 is a light source that emits a nanosecond laser. The second laser light source 27 may be capable of emitting a laser having a pulse width of femtoseconds or longer. The laser emitted by the second laser light source 27 is not limited to a nanosecond laser. The second laser light source 27 may also be a light source that emits a picosecond laser.

[0024] The laser processing device 25 includes an irradiation unit 29 that irradiates the base material 6 with a femtosecond laser 28 or a nanosecond laser. The first laser light source 26 and the irradiation unit 29 are connected by a first optical fiber 31. The femtosecond laser 28 emitted by the first laser light source 26 is supplied to the irradiation unit 29 through the first optical fiber 31. The second laser light source 27 and the irradiation unit 29 are connected by a second optical fiber 32. The nanosecond laser emitted by the second laser light source 27 is supplied to the irradiation unit 29 through the second optical fiber 32.

[0025] The irradiation unit 29 includes a condenser lens 29a and a shutter 29b. The condenser lens 29a condenses the femtosecond laser 28 and the nanosecond laser on the surface of the substrate 6. The diameter of the first condenser 28a where the femtosecond laser 28 and the nanosecond laser are condensed is not limited, but is, for example, 25 μm in this embodiment. The shutter 29b switches between irradiation and non-irradiation of the femtosecond laser 28 and the nanosecond laser.

[0026] The laser processing device 25 includes an X-table 33 that moves the irradiation unit 29 in the X-direction. The laser processing device 25 includes a Y-table 34 that moves the substrate 6 in the Y-direction. The X-table 33 and the Y-table 34 are equipped with servo motors (not shown).

[0027] The laser processing apparatus 25 includes a control device 35. The control device 35 controls the moving speed and amount of movement of the X-table 33 and the Y-table 34. The control device 35 includes a storage unit 36. The storage unit 36 ​​stores coordinate data of a path along which the femtosecond laser 28 is irradiated onto the substrate 6. The control device 35 can scan the femtosecond laser 28 or the nanosecond laser within a predetermined pattern based on the coordinate data of the path.

[0028] The control device 35 is electrically connected to the first laser light source 26, the second laser light source 27, and the irradiation unit 29. The control device 35 controls the start and stop of light emission of the first laser light source 26 and the second laser light source 27. The control device 35 controls the opening and closing of the shutter 29b of the irradiation unit 29.

[0029] In step S1, the first laser light source 26 emits a femtosecond laser 28, and the second laser light source 27 stops emitting light. The femtosecond laser 28 is irradiated onto the substrate 6. Asperities 37 are formed on the surface of the substrate 6 along the path of irradiation with the femtosecond laser 28. By irradiating the femtosecond laser 28, an ablation process is performed in which metal molecules on the surface of the substrate 6 are instantaneously vaporized and dispersed. A surface with high surface roughness and low gloss is formed by the ablation process.

[0030] As shown in Fig. 6, a plurality of first loci 38, which are loci along which the femtosecond laser 28 is irradiated, are arranged in parallel. The first loci 38 may be curved or straight. The first loci 38 may be a pattern that combines curved and straight lines. As a result, the projections and recesses 37 are arranged without gaps within a predetermined pattern.

[0031] There are no particular limitations on the conditions for irradiating the femtosecond laser 28. In this embodiment, for example, the laser fluence of the first focusing part 28a of the femtosecond laser 28 is 2600 to 2700 mJ / cm 2 The frequency of the laser pulse is about 505 kHz. The scanning speed is 1300 mm. The pitch of the laser pulse irradiated area is 2.6 μm.

[0032] As shown in FIG. 7, the first processed surface 12 of the first pattern 13, the second pattern 15, the third pattern 16, the fourth pattern 17, and the fifth pattern 18 are formed on the base material 6 of the backing plate 5.

[0033] 8 and 9 are diagrams corresponding to the second processing step of step S2. As shown in FIG. 8, a laser processing device 25 is used. In step S2, the first laser light source 26 stops emitting light, and the second laser light source 27 emits a nanosecond laser 39 as a second laser. The nanosecond laser 39 is irradiated onto the substrate 6. The diameter of the second focusing portion 39a where the nanosecond laser 39 is focused is 25 μm. The laser fluence of the second focusing portion 39a of the nanosecond laser 39 is 350 to 450 mJ / cm. 2The frequency of the laser pulse is about 100 kHz. The scanning speed is 400 mm. The pitch of the places irradiated with the laser pulse is 4 μm. The pitch of the places irradiated with the laser pulse is not particularly limited, but when the diameter of the second focusing portion 39a is 25 μm, the pitch is preferably 3 μm or more and 10 μm or less. The value obtained by dividing the pitch by the diameter of the second focusing portion 39a is preferably 0.12 or more and 0.4 or less. If the pitch is less than 3 μm, the productivity is low. If the pitch exceeds 10 μm, the uniformity of the appearance is impaired. By irradiating the nanosecond laser 39 at equal intervals with a constant pitch, the thickness of the oxide film can be made closer to constant.

[0034] When the second light collecting portion 39a having a diameter of 25 μm is irradiated every 4 μm, the second light collecting portion 39a partially overlaps. The overlapping area divided by the area of ​​the second light collecting portion 39a is preferably 50% or more and 90% or less. If the overlapping rate is less than 50%, the uniformity of the appearance is lost. If the overlapping rate exceeds 90%, the productivity decreases.

[0035] The irregularities 37 are oxidized along the path of irradiation with the nanosecond laser 39. The surface of the base material 6 is heated by irradiation with the nanosecond laser 39. As the base material 6 is heated in the atmosphere, the metal molecules combine with oxygen and are oxidized. It is also assumed that the protruding parts of the irregularities 37 melt because it is difficult to dissipate heat. Therefore, a surface with low surface roughness and high gloss is formed by melting and oxidizing due to heating.

[0036] As shown in Fig. 9, a plurality of second loci 41, which are loci along which the nanosecond laser 39 is irradiated, are arranged in parallel. The second loci 41 may be curved or straight. As a result, the surface irregularities 37 within a predetermined pattern are oxidized without any gaps. In Fig. 9, the first locus 38 and the second locus 41 are arranged to intersect. However, this is not limiting, and the first locus 38 and the second locus 41 may be parallel or overlap. The first locus 38 and the second locus 41 may be loci unrelated to each other.

[0037] 1, a nanosecond laser 39 is irradiated onto the first processed surface 12 of the second pattern 15, the third pattern 16, the fourth pattern 17, and the fifth pattern 18. As a result, the second processed surface 14 is formed by covering the first processed surface 12 in the second pattern 15, the third pattern 16, the fourth pattern 17, and the fifth pattern 18.

[0038] The surface of the first processed surface 12 is a surface formed by irradiation with a femtosecond laser 28. Therefore, as shown in Fig. 10, the first processed surface 12 has large irregularities 37 and a large first surface roughness. The surface of the first processed surface 12 is a surface formed by ablation processing. Therefore, the metal molecules are not bonded to oxygen, and the oxide film 42 is thin.

[0039] The surface of the second processed surface 14 is a surface formed by irradiating the first processed surface 12 with a nanosecond laser 39. Therefore, as shown in Fig. 11, the second processed surface 14 has small irregularities 37 and a small second surface roughness. Since the surface of the first processed surface 12 is a surface heated in the atmosphere, the thickness of the oxide film 42 is thicker than that of the first processed surface 12.

[0040] The thickness of the oxide film is measured, for example, by the following method: the backing plate 5 is hardened with resin. Next, the hardened resin and the backing plate 5 are cut, and the cross section of the hardened resin is polished. The cross section of the resin and the backing plate 5 is observed by a scanning electron microscope, and the thickness of the oxide film 42 is measured.

[0041] According to this manufacturing method, in step S1, a femtosecond laser 28 is irradiated onto the surface of the base material 6 of the receiving plate 5, which is a metal part. The femtosecond laser 28 is a laser with a pulse width at the femtosecond level. A predetermined pattern is formed by a first trajectory 38 of the femtosecond laser 28. This pattern includes designs, characters, figures, and the like. An ablation process is performed by the femtosecond laser 28, which instantaneously vaporizes and disperses metal. The surface on which the pattern is formed by the ablation process is the first processed surface 12. A nanosecond laser 39 of the second laser is irradiated onto a part of the first processed surface 12. The pulse width of the second laser is equal to or greater than the pulse width of the femtosecond laser 28. Therefore, an oxide film 42 is formed at the location irradiated with the second laser. The surface on which this oxide film 42 is formed is the second processed surface 14. The oxide film 42 of the second processed surface 14 is thicker than the oxide film 42 of the first processed surface 12. A thicker oxide film 42 has a smaller surface roughness and a glossier surface than a thinner oxide film 42. Therefore, the second processed surface 14 can be made glossier than the first processed surface 12. As a result, the second processed surface 14 is glossier than the first processed surface 12, and therefore can have an aesthetically pleasing appearance.

[0042] According to this manufacturing method, the second laser used in step S2 is a nanosecond laser 39. The nanosecond laser 39 is a laser with a pulse width at the nanosecond level. The nanosecond laser 39 can turn the first processed surface 12 into a glossy second processed surface 14 without destroying the pattern formed by the femtosecond laser 28.

[0043] On the second processed surface 14, the oxide film 42 has a thickness greater than 0 nm and equal to or less than 10 nm. According to this manufacturing method, since the thickness of the oxide film 42 on the second processed surface 14 is greater than 0 nm, a glossy surface can be obtained. Since the thickness of the oxide film 42 on the second processed surface 14 is equal to or less than 10 nm, the pattern formed by irradiating the femtosecond laser 28 can be made visible without being destroyed. Since the thickness of the oxide film 42 on the second processed surface 14 is equal to or less than 10 nm, the oxide film 42 is transparent.

[0044] According to this configuration, the first processed surface 12 is formed by irradiating the base material 6 made of titanium, titanium alloy, or stainless steel with a femtosecond laser 28. Furthermore, the second processed surface 14 is formed by irradiating the base material 6 with a nanosecond laser 39. Titanium, titanium alloy, and stainless steel are difficult to plate, so it is difficult to plate them to vary their appearance. Therefore, even if the material of the watch component is titanium, titanium alloy, or stainless steel, which are difficult to plate, it is possible to add a lot of variation to the appearance.

[0045] Timepiece 1 is equipped with the above-mentioned receiving plate 5. According to this configuration, the receiving plate 5 equipped on timepiece 1 has an exterior design with appeal. Therefore, timepiece 1 can be a timepiece equipped with timepiece parts that have an exterior design with appeal.

[0046] Second embodiment This embodiment differs from the first embodiment in that the first pattern 13 of the first region 8 shown in Fig. 1 is a second processed surface 14. Note that the same components as those in the first embodiment are denoted by the same reference numerals and redundant explanations will be omitted.

[0047] 12, a watch 45 has a backing plate 46 as a watch part and a metal part. The backing plate 46 has a metal base material 47. The material of the base material 47 is the same as that of the base material 6 of the first embodiment.

[0048] The substrate 47 has a first region 8, a second region 9, and a third region 11. The surfaces of the substrate 47 in the first region 8 and the second region 9 form a second processed surface 14. The shape of the first region 8 is a first pattern 13. The second processed surface 14 of the second region 9 consists of four parts. The shapes of the four parts are a second pattern 15, a third pattern 16, a fourth pattern 17, and a fifth pattern 18.

[0049] The second processed surface 14 is formed by irradiating the first processed surface 12 with a second laser having a pulse width equal to or greater than the pulse width of the femtosecond laser 28. Therefore, the second processed surface 14 is a surface that covers the entire first processed surface 12.

[0050] The surface roughness of the first processed surface 12 is a first surface roughness. The surface roughness of the second processed surface 14 is a second surface roughness. The second surface roughness is 0.1 μm or more and 0.3 μm or less. The second surface roughness is smaller than the first surface roughness. The backing plate 46 has the first processed surface 12 and the second processed surface 14, and the second processed surface 14 covers the entire first processed surface 12.

[0051] According to this configuration, the surface of the base material 47 has a second processed surface 14. The second processed surface 14 is a surface covering the first processed surface 12. The first processed surface 12 has a greater surface roughness and a lower gloss than the second processed surface 14. The second processed surface 14 has a smaller surface roughness and a higher gloss than the first processed surface 12. The second processed surface 14 is a high gloss surface, and can be given an appearance with a more aesthetic appeal than the first processed surface 12, which has a lower gloss.

[0052] Next, a method for manufacturing the above-mentioned backing plate 46 will be described with reference to Fig. 4. In the flow chart of Fig. 4, the first processing step S1 is the same as in the first embodiment.

[0053] In the second processing step of step S2, a second laser having a pulse width of femtoseconds or longer is irradiated onto all of the first processed surfaces 12 to form a second processed surface 14 having a smaller surface roughness than the first processed surfaces 12 and a thicker oxide film 42 than the first processed surfaces 12. Through the above steps, the second processed surface 14 covering the first processed surfaces 12 is completed.

[0054] According to this manufacturing method, the second laser is irradiated to all locations of the first processed surface 12. An oxide film 42 is formed in the locations irradiated with the second laser. The surface on which this oxide film 42 is formed is the second processed surface 14. The oxide film 42 on the second processed surface 14 is thicker than the oxide film on the first processed surface 12. A thicker oxide film 42 results in less surface roughness and a glossy surface compared to a thinner oxide film 42. Therefore, the second processed surface 14 can be made glossier than the first processed surface 12. As a result, the second processed surface 14 is glossier than the first processed surface 12, and can therefore be made to have an aesthetically pleasing appearance.

[0055] Third embodiment In the first embodiment, the thickness of the oxide film 42 on the second processed surface 14 is set to 10 nm or less. The thickness of the oxide film 42 may exceed 10 nm. As shown in Fig. 13, when the thickness of the oxide film 42 exceeds 10 nm, a colored surface is observed. By adjusting the color tone, it is possible to achieve an appearance with a design.

[0056] The thickness of the oxide film 42 can be controlled by increasing or decreasing the amount of energy received by the nanosecond laser 39 on the substrate 6. Parameters related to the amount of energy include the scanning speed, frequency, and the laser fluence of the second focusing unit 39a. The frequency indicates the frequency of the nanosecond laser 39 emitted from the irradiation unit 29. For example, it is assumed that the parameters other than the frequency are fixed. If it is desired to increase the film thickness, the frequency is increased and the pitch of the second focusing unit 39a is shortened. In addition, it is assumed that the parameters other than the scanning speed are fixed. If it is desired to increase the film thickness, the scanning speed is decreased and the pitch of the second focusing unit 39a is shortened. In this way, the thickness of the oxide film 42 can be controlled by controlling the amount of energy received by the substrate 6.

[0057] Fourth embodiment In the first embodiment, the manufacturing process is completed when the second laser is irradiated to form the second processed surface 14. Furthermore, the second processed surface 14 may be plated with various metals. By adjusting the color tone, it is possible to create an appearance with a design.

[0058] Fifth embodiment In the first embodiment, the nanosecond laser 39 is irradiated at equal intervals with a constant pitch. The nanosecond laser 39 may be irradiated by gradually switching the pitch. Since the thickness of the oxide film 42 gradually changes, a gradation in glossiness can be achieved. By gradually increasing the thickness of the oxide film 42, a gradation in color tone can be achieved. The trajectory along which the second light collecting section 39a moves is defined as a scanning line. A gradation can be achieved in the direction of the scanning line.

[0059] By gradually changing the interval between the scanning lines, the thickness of the oxide film 42 changes gradually, so that a gradation in glossiness can be achieved. A gradation can be achieved in the direction intersecting the scanning lines.

[0060] Sixth embodiment In the first embodiment, the first processed surface 12 and the second processed surface 14 were formed on the receiving plate 5. In the second embodiment, the first processed surface 12 and the second processed surface 14 were formed on the receiving plate 46. In addition, the timepiece part on which the first processed surface 12 and the second processed surface 14 are formed may be any one of receiving members such as the receiving plate 5 and the receiving plate 46, a circuit cover, an oscillating weight, a main plate, a back cover, a dial, hands, and a balance.

[0061] According to this configuration, any one of the receiver member, circuit cover, oscillating weight, main plate, back cover, dial, hands, and balance has a first processed surface 12 and a second processed surface 14. The second processed surface 14 is a surface that adds gloss to the pattern of the first processed surface 12. Therefore, the receiver member, circuit cover, oscillating weight, main plate, back cover, dial, hands, and balance that have the second processed surface 14 can enhance the decorativeness of the timepiece. [Explanation of symbols]

[0062] 1,45...clock, 5,46...backing plate as clock part and metal part, 6,47...substrate, 12...first processed surface, 13...first pattern as pattern, 14...second processed surface, 15...second pattern as pattern, 16...third pattern as pattern, 17...fourth pattern as pattern, 18...fifth pattern as pattern, 28...femtosecond laser, 39...nanosecond laser as second laser, 42...oxide film.

Claims

1. A step of forming a first processed surface having a predetermined pattern by irradiating a surface of a metal part with a first laser having a femtosecond pulse width; and forming a second processed surface having a smaller surface roughness than the first processed surface and a thicker oxide film than the first processed surface by irradiating at least a portion of the first processed surface with a second laser having a pulse width of femtoseconds or more.

2. A method for manufacturing a watch component according to claim 1, A method for manufacturing a watch component, wherein the second laser is a nanosecond laser.

3. A method for manufacturing a watch component according to claim 1 or 2, comprising the steps of: A method for manufacturing a watch component, characterized in that the thickness of the oxide film on the second processed surface is greater than 0 nm and less than 10 nm.

4. Metallic substrate and a first processed surface having a predetermined pattern formed by irradiating the base material with a first laser having a femtosecond pulse width and having a first surface roughness; a second processed surface having a second surface roughness smaller than the first surface roughness, the second processed surface being formed by irradiating the first processed surface with a second laser having a pulse width of femtoseconds or more; the second work surface covers at least a portion of the first work surface; A watch component, wherein the second surface roughness is 0.1 μm or more and 0.3 μm or less.

5. A timepiece component according to claim 4, The timepiece part is any one of a receiver member, a circuit cover, an oscillating weight, a main plate, a back cover, a dial, a pointer, and a balance.

6. A timepiece component according to claim 4 or 5, A watch component characterized in that the base material is titanium, a titanium alloy, or stainless steel.

7. A timepiece comprising a timepiece component according to any one of claims 4 to 6.

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