JPH11256364A - Surface treating method for metallic member and metallic member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface treating method for a metallic member capable of deeply forming a fine pattern regardless of the surface shape of the metallic member and capable of obtaining the three-dimensional appearance and to provide a metallic member subjected to the surface treatment. SOLUTION: This method comprises stages (1a and 1b) in which a protective layer 2 is formed on the surface of a metallic member 1, a stage (1c) in which a masking film 3 is formed on the protective film 2, a stage (1d) in which laser beam is applied, by which at least the masking film 3 is subjected to patterning and stage (1e) in which the metallic member 1 is subjected to etching by using the masking film 3. As for the working by laser beam, it is preferable to remove the protective layer 2 and a part of the metallic member 1 together with the masking film 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating a surface of a metal member, and more particularly to a method for etching a surface of a metal member to form a predetermined pattern and a metal member subjected to a surface treatment.

[0002]

2. Description of the Related Art Generally, in order to form a concave pattern on the surface of a metal member such as a watch exterior part, a plating method or a printing method has been used.

For example, in the case of the plating method, after printing a target pattern, characters, scales and the like, a mask is formed by electrolytic plating or the like, and then the printed portion is peeled off and etched to form a concave pattern. I was

In the case of the printing method, mask printing is performed while leaving a target pattern portion, and after etching, the mask is removed to form a concave pattern.

However, according to these methods, when printing a desired pattern, it is very difficult to print a design that wraps around a curved surface or an uneven surface or a side surface of a metal member. At the time of formation, application of a mask material or the like has been performed manually.

[0006] As described above, the mask formed by the manual operation has a blurred pattern boundary, an uneven film thickness, and poor film properties. The kinks at the pattern boundaries directly lead to the kinks of the etching pattern, and when the film thickness is non-uniform, the thin film thickness cannot withstand long-time etching, resulting in rough surface of the metal member surface and poor appearance. In addition, there is a problem in that a portion having a large film thickness becomes a mask residue when the mask is peeled off, or if the peeling is performed for a long time so that the mask is not left, the surface of the metal member becomes rough.

On the other hand, fine processing is performed on a metal member by irradiating a high energy laser such as an excimer laser. According to such laser processing, the metal member can be directly processed, so that the process can be simplified. In addition, since the irradiation direction of the laser can be freely changed, it is possible to accurately pattern a design that goes around a curved surface or a side surface.

However, in the case of laser processing, only a groove of about 10 μm is provided on the metal surface, and if a powerful laser is irradiated to form a deeper recess (about 20 μm or more) or the irradiation time is increased, In addition, burrs and the like are generated at the peripheral portion of the irradiated portion due to irradiation heat, and it is difficult to provide a three-dimensional and sophisticated design.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for surface treatment of a metal member capable of forming a precise three-dimensional pattern and obtaining a three-dimensional appearance regardless of the surface shape of the metal member. And to provide a metal member subjected to such a surface treatment.

[0010]

This and other objects are achieved by the present invention which is defined below as (1) to (40).

(1) a step of forming a protective layer on the surface of a metal member, a step of forming a masking film on the protective layer, and a step of patterning at least the masking film by irradiating a laser beam; Etching the metal member using the masking film.

(2) The surface treatment method for a metal member according to the above (1), wherein the protective layer is a corrosion-resistant layer that imparts at least corrosion resistance to the metal member.

(3) The surface treatment method for a metal member according to the above (1) or (2), wherein the protective layer comprises two or more different thin films.

(4) The method according to any one of the above (1) to (3), wherein the protective layer is formed by plating.

(5) The protective layer has a thickness of 0.5 to 30.
The surface treatment method for a metal member according to any one of the above (1) to (4), wherein the thickness is μm.

(6) The surface treatment method for a metal member according to any one of (1) to (5), wherein at least a part of the protective layer is removed together with the masking film by the laser beam.

(7) The surface treatment method for a metal member according to any one of the above (1) to (5), wherein the laser beam removes a part of the protective layer and the metal member together with the masking film.

(8) The method according to any one of (1) to (7), wherein the masking film is formed by electrodeposition coating.

(9) The masking film has a thickness of 10
The surface treatment method for a metal member according to any one of the above (1) to (8), which has a thickness of from 30 to 30 μm.

(10) The surface treatment method for a metal member according to any one of the above (1) to (9), wherein the depth of the concave portion formed in the metal member by the etching is 20 μm or more.

(11) The surface treatment method for a metal member according to any one of (1) to (10), wherein the etching is wet etching.

(12) The surface treatment method for a metal member according to (11), wherein the etching is shower etching.

(13) The surface treatment method for a metal member according to any one of (1) to (12), wherein a coating layer is formed in the recess.

(14) The surface treatment method for a metal member according to any one of (1) to (13), wherein a colored layer is formed in the recess.

(15) The surface treatment method for a metal member according to any one of the above (1) to (14), wherein the metal member is a watch exterior part.

(16) a step of forming a protective layer on the surface of the metal member; a step of forming at least one underlayer on the protective layer; a step of forming a masking film on the underlayer; A surface treatment method for a metal member, comprising: a step of patterning at least the masking film by irradiating light; and a step of etching the metal member using the patterned masking film.

(17) The surface treatment method for a metal member according to the above (16), wherein the protective layer is a corrosion-resistant layer that imparts at least corrosion resistance to the metal member.

(18) The surface treatment method for a metal member according to the above (16) or (17), wherein the protective layer comprises two or more different thin films.

(19) The method according to any one of the above (16) to (18), wherein the protective layer is formed by plating.

(20) The protective layer has a thickness of 0.5 to 30.
The surface treatment method for a metal member according to any one of the above (16) to (19), wherein the thickness is μm.

(21) The surface treatment method for a metal member according to any one of the above (16) to (20), wherein the underlayer is an adhesion reinforcing layer for improving the adhesion of the masking film.

(22) The surface treatment method for a metal member according to (21), wherein the adhesion reinforcing layer is formed by wet plating or dry plating.

(23) The adhesion reinforcing layer is made of Au or Au.
The surface treatment method for a metal member according to the above (21) or (22), comprising a system alloy thin film.

(24) The surface treatment method for a metal member according to any one of the above (21) to (23), wherein the thickness of the adhesion reinforcing layer is 1 μm or less.

(25) The surface treatment method for a metal member according to any one of (16) to (24), wherein at least a part of the protective layer is removed together with the masking film by the laser beam.

(26) The surface treatment method for a metal member according to any one of the above (16) to (24), wherein the laser beam removes a part of the protection layer and the metal member together with the masking film.

(27) The method according to any one of the above (16) to (26), wherein the masking film is formed by electrodeposition coating.

(28) The masking film has a thickness of 10
The surface treatment method for a metal member according to any one of the above (16) to (27), which has a thickness of from 30 to 30 μm.

(29) The method according to any one of the above (16) to (28), wherein the etching is wet etching.

(30) The method for surface treating a metal member according to the above (29), wherein the etching is shower etching.

(31) The surface treatment method for a metal member according to any one of the above (16) to (30), wherein a depth of the concave portion formed in the metal member by the etching is 20 μm or more.

(32) The surface treatment method for a metal member according to any one of the above (16) to (31), wherein a coating layer is formed in the concave portion.

(33) The surface treatment method for a metal member according to any one of the above (16) to (32), wherein a colored layer is formed in the concave portion.

(34) The surface treatment method for a metal member according to any one of the above (16) to (33), wherein the metal member is a watch exterior part.

(35) A metal member having a concave portion of a predetermined pattern formed on the surface, a protective layer is formed on the surface of the metal member, and the concave portion is partially formed by irradiating a laser beam. A metal member characterized by being completed by:

(36) The protective layer has a thickness of 0.5 to 30.
The metal member according to the above (35), which is μm.

(37) The metal member according to the above (35) or (36), wherein the depth of the concave portion formed in the metal member is 20 μm or more.

(38) The metal member according to any one of (35) to (37), wherein a coating layer is formed in the recess.

(39) The metal member according to any one of (35) to (38), wherein a colored layer is formed in the recess.

(40) The metal member according to any one of the above (35) to (39), wherein the metal member is a watch exterior part.

[0051]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a metal member according to a first embodiment of the present invention;

FIGS. 1A to 1G are cross-sectional views showing a first embodiment of the method for treating the surface of a metal member according to the present invention.

As shown in this figure, the method for treating the surface of a metal member according to the present invention comprises the steps (1a, 1b) of forming a protective layer 2 on the surface of a metal member 1, and a masking film 3 on the protective layer 2. (1c), patterning at least the masking film 3 by irradiating a laser beam (1d), and etching the metal member 1 using the masking film 3 (1e).

The metal member 1 may be made of any metal material. For example, in the case of a material for a watch exterior part such as a wristwatch, it is selected from the viewpoints of corrosion resistance, strength, manufacturing cost, and the like. , Stainless steel (SU
S), brass (Bs), alloys such as nickel silver (NS), and metal materials such as Ti and Ti-based alloys, noble metals such as Au, Ag, and Pt, and alloys including these noble metals.

<Formation of Protective Layer> First, a protective layer 2 is formed on the surface of the metal member 1 as described above (1b). This can prevent physical and chemical changes of the metal member caused by contact with a normal use environment, for example, body fluid such as water, air, and sweat. Further, it is possible to improve the adhesion of a masking film described later, and further enhance the mask function together with the underlayer and the masking film.

As such a protective layer 2, for example, corrosion resistance, weather resistance, water resistance, oil resistance, abrasion resistance, discoloration resistance, etc. are imparted to a metal member, and rust prevention, antifouling, antifogging, and scratch resistance are provided. And the like, and may exhibit two or more effects. However, it is preferable that the layer is a corrosion-resistant layer that imparts at least corrosion resistance.

The protective layer 2 is not particularly limited, and may be, for example, an organic compound such as a resin, an Au-based alloy such as Au or Au—Fe, a metal such as a Pd or Pd-based alloy, Cr or a Cr alloy, or a metal oxide. And a passivation film formed on a metal surface.

The protective layer 2 is preferably composed of at least two or more different thin films. Thereby, a synergistic protection effect can be exhibited based on the properties of each thin film. The protective layer composed of at least two or more different thin films may be composed of any combination of the above-mentioned thin film mainly composed of an organic compound or an inorganic compound and a passive film.

The thickness of the protective layer 2 is preferably about 0.5 to 30 μm. If the thickness of the protective layer 2 is too small, effects such as imparting corrosion resistance may not be sufficiently obtained. If the thickness is too large, the adhesion and crack resistance of the protective layer 2 may be insufficient. There is.

The protective film 2 is preferably formed by plating. This makes it possible to form a thin film having excellent adhesion, wear resistance and the like. Further, the protective layer 2 can be formed irrespective of the shape and size of the metal member 1, and the film thickness can be easily adjusted.

The thin film formed as the protective layer 2 includes
For example, Au or Au alloy, pure Pd or Pd alloy, P
t or Pt alloy, Cu or Cu alloy, Cr or C
r alloy, Ru or Ru alloy, Ti, Ti alloy or T
and a plating layer composed of an i-compound or the like. Further, the protective layer 2 may be formed by IP using the above metal as a constituent material.

When the protective layer 2 is composed of two or more different thin films, it is preferable that at least one layer is formed by plating. According to plating, it is easy to form a thin film having a uniform thickness regardless of the surface shape of the metal member 1.

The plating method that can be used in forming the protective layer 2 is not particularly limited, and examples include wet plating such as electrolytic plating and electroless plating, and dry plating such as vapor deposition, sputtering, and ion plating (IP). Can be

Hereinafter, in this embodiment, the description is made assuming that the protective layer 2 is a corrosion-resistant layer, but the present invention is not particularly limited to the corrosion-resistant layer.

<Formation of Masking Film> Next, a masking film 3 is formed on the above-mentioned protective layer 2 (1c). This masking film 3 functions as an etching mask in an etching step described later.

The masking film 3 is made of a material that ablates when irradiated with a laser beam. This enables mask patterning with laser light. Also, by ablation of the masking film 3,
The protection layer 2 and the metal member 1 are exposed, and a part thereof is also removed by the laser beam, so that marking can be performed.

The material constituting such a masking film 3 is not particularly limited as long as it is a material that absorbs laser light. For example, an acrylic resin, a polyimide resin,
A resin material such as a polysulfone-based resin, an epoxy-based resin, and a fluorine-based resin can be used. Further, Au, Ni, Pd,
Metal materials such as Cu, Ag, Ti, and Cr can be used.

The masking film 3 is preferably transparent. This makes it possible to visually confirm the state of close contact with the metal member 1 from the outside.

The method of forming the masking film 3 is not particularly limited, and examples include spray coating, electrostatic coating, electrodeposition coating, etc., wet plating, dry plating (evaporation, IP, etc.).
Of these, electrodeposition coating is preferred. According to the electrodeposition coating, the film thickness of the masking film 3 can be formed more uniformly.
After etching, the masking film 3 formed in a uniform film thickness is removed by, for example, immersion in a stripping solution. At this time, the masking film in a portion having a large film thickness remains,
There is no possibility that the surface of the metal member will be roughened due to, for example, a portion having a small film thickness being exposed to the stripping solution for a long time.

When the mask is removed with a laser, if the film thickness is not uniform, the mask may remain partially. However, in the electrodeposition coating with a uniform film thickness, a uniform mask is used. Removal is possible.

The thickness of the masking film 3 formed by electrodeposition coating or the like is preferably about 10 to 30 μm. If the film thickness is too small, a pinhole may be generated in the masking film 3, and an etching failure may occur at that location. In particular, when the etching time is increased, the function as an etching mask may not be sufficiently exhibited. On the other hand, if the film thickness is too large, the dispersion of the film thickness may be large, and in such a case,
When the masking film 3 is removed, the surface of the metal member 1 may be roughened by the stripping solution as described above. On the other hand, when the film thickness is large, the internal stress of the film is increased, the adhesion is reduced, and cracks are generated, so that the mask portion is roughened at the time of etching.

<Laser Processing> Next, by irradiating a laser beam, at least the masking film 3 is patterned to form an etching mask (1d).
By performing mask patterning using laser light, the process can be simplified as compared with, for example, a case using photolithography or the like. In addition, the use of laser light makes it possible to form a fine precision pattern without burrs.
Furthermore, since the irradiation position and angle of the laser beam can be set arbitrarily, even when forming a pattern on a curved surface or uneven surface,
It can be performed easily and accurately. Correction of side etching when the etching depth is increased can be easily performed by a laser scanning program.

When patterning the masking film 3 with a laser beam, it is preferable to remove at least a part of the protective layer 2, and more preferably to remove a part of the metal member 1.

Thus, at least a part of the protective layer 2,
Alternatively, a pattern having the same shape as the pattern formed on the masking film 3 is marked on the surfaces of the protective layer 2 and the metal member 1, so that the etching in the next step can be performed more efficiently. That is, since a rough concave pattern is formed on the protective layer 2 and the metal member 1 by laser in advance, the etchant enters the concave pattern portion,
Etching of the metal member proceeds rapidly. In particular, the protective layer 2 having corrosion resistance or the like may be difficult to etch, and if at least a part of the protective layer 2 is removed by a laser, the etching can be performed more quickly.

Further, when a part of the metal member 1 is removed by a laser, a sharp processed end face can be obtained, and a clear pattern without so-called burrs and burrs can be obtained.

The laser used in the method of the present invention includes, for example, Ne-He laser, Ar laser,
Gas laser such as CO ₂ laser, ruby laser,
Solid-state lasers such as a semiconductor laser, a YAG laser, and a glass laser are exemplified. Above all, a YAG laser is preferably used because continuous oscillation can be easily performed at room temperature and good controllability in a low irradiation energy region is achieved.

The irradiation conditions of the laser beam are appropriately selected depending on the materials and thicknesses of the masking film 3, the underlayer 2, and the metal member 1. For example, in the case of a YAG laser, the energy intensity is about 10 to 50 W. Is preferred.

<Etching Step> Next, etching is performed using the masking film 3 patterned by a laser beam (1e).

Thus, the concave portions 5 having a predetermined pattern can be formed in the masking film 3. Further, according to the etching, the depth of the concave portion 5 can be arbitrarily set by selecting an etching solution, an etching time and the like. Thereby, it is possible to etch to a depth that is difficult by a method of directly patterning (marking) the surface of the metal member 1 with a laser beam. That is, in the patterning of the metal surface by the laser beam, the laser intensity is increased or the irradiation time is lengthened to form a deep concave portion. However, if the strength and irradiation time are excessive, scorching, deformation, burrs, and burrs may occur at the periphery of the irradiated part due to thermal melting, which deteriorates the surface appearance of the metal member and makes it difficult to control the depth. May also be large.

In the present invention, the etching method is not particularly limited, but wet etching such as immersion etching and shower etching is preferable, and shower etching is particularly preferable. According to the shower etching, a deep concave of a predetermined pattern can be clearly formed in the metal member in a shorter time.

The depth of the concave portion 5 formed in the metal member 1 by etching is not particularly limited, but is preferably 20 μm or more, and more preferably 50 μm or more. As a result, the concave portion 5 having a predetermined pattern such as a pattern or a character formed on the surface of the metal member 1 appears more three-dimensionally and can be visually recognized clearly.

After the etching, a coating layer 7 is preferably provided in the recess 5 (1f). Thereby, corrosion resistance or the like can be imparted to the inside of the concave portion 5 where the protective layer 2 is not formed. At the same time, the color tone, texture, and the like of the concave portion 5 can be adjusted by selecting the coating layer 7.

Examples of the constituent material of the coating layer 7 include the same materials as those of the protective layer 2 described above. In particular, Au or Au alloy plating, Pd or Pd alloy plating, Pt or Pt
Alloy plating, a plating layer made of Cu or a Cu alloy or the like is preferable.

The thickness of the coating layer 7 is preferably about 0.5 to 10 μm. If the coating layer 7 is too thin, it may not be possible to impart or improve corrosion resistance or the like. On the other hand, if the thickness is too large, cracks may occur in the coating layer 7.
The amount of a noble metal material such as Au used for forming the metal is increased, and the manufacturing cost is increased. Such a coating layer 7 can be formed by various plating methods similarly to the protective layer 2.

Further, as shown in FIG. 2, it is preferable to form the coloring layer 8 after providing the coating layer 7 in the concave portion 5. Thereby, a multicolor design can be applied to the surface of the metal member 1, and the design variation is expanded. For example, a combination of the color tone of the colored layer 8 and the color tone of the metal member 1 itself can provide an aesthetic appearance such as a three-dimensional appearance and luxury.

The method for forming the colored layer 8 is not particularly limited, and examples thereof include wet plating such as Au plating, black Cr plating, Ag plating, Pd plating, Rh plating, Cr plating, Ru plating, and color plating, and ion plating. , Dry coating, coating, coating with paint, etc., and these methods may be combined.

In the case where the colored layer 8 is formed by plating, it is preferable to form the colored layer 8 after etching and before removing the masking film 3. Thereby, the colored layer 8 can be easily formed only in the concave portion 5. When the colored layer 8 is formed by plating, the colored layer 8 having excellent adhesion and abrasion resistance can be formed regardless of the shape and size of the concave portion. Further, it is easy to control the thickness of the colored layer 8.

When the colored layer 8 is formed by putting paint,
For example, after removing the masking film 3, a paint is applied,
The paint adhered to the surface of the metal member 1 is wiped off. Next, the coloring layer 8 is formed by heating and drying the paint in the recess 5.

Finally, the masking film 3 is removed to obtain a metal member as shown in the figure (1 g). The method of removing the masking film 3 may be any method, for example, a method of dissolving and removing the masking film 3 by immersing it in a stripping solution composed of a solvent, an alkaline solution or the like.

FIGS. 3 (3a) to 3 (h) are sectional views showing a second embodiment of the method for treating the surface of a metal member according to the present invention.

As shown in this figure, the method for treating the surface of a metal member according to the present embodiment includes a step (3a, 3b) of forming a protective layer 2 on the surface of the metal member, A step (3c) of forming the ground layer 9, a step (3d) of forming the masking film 3 on the underlayer 9, a step of patterning at least the masking film 3 by irradiating a laser beam (3e), and patterning. (3f) etching the metal member 1 using the masking film 3 thus formed.

Except that the underlayer 9 is formed, it is the same as the first embodiment. Hereinafter, differences from the first embodiment will be mainly described.

In the method of this embodiment, at least one underlayer 9 is formed on the protective layer 2 (4b). The underlayer 9 is not particularly limited, but is preferably an adhesion reinforcing layer for improving the adhesion between the metal member 1 and the masking film 3. As a result, the adhesiveness / adhesiveness of the masking film 3 is further improved, and it is possible to effectively prevent burrs and burrs on the periphery of the concave portion due to poor etching such as seepage.

As such an adhesion reinforcing layer, for example, A
Examples of the thin film include u, Ni, Pd, Cr, and alloys thereof, and a thin film of Au or an Au-based alloy is preferable. Thereby, the adhesiveness and adhesiveness of the masking film can be more effectively improved.

The method for forming the adhesion reinforcing layer is not particularly limited, but wet plating or dry plating is preferred. Examples of wet plating include electrolytic plating and electroless plating, and examples of dry plating include vapor deposition, sputtering, and IP.
(Ion plating) and the like.

The thickness of the adhesion reinforcing layer is preferably 1 μm or less, more preferably a strike plating layer of 0.5 μm or less. Thereby, it is possible to prevent the variation in the film thickness and the occurrence of cracks while improving the adhesion, thereby suppressing an increase in the manufacturing cost.

Next, a masking film 3 is formed on the underlayer 9 (3d). The constituent material, film properties, and forming method of the masking film 3 are the same as those in the first embodiment.

Further, at least the masking film 3 is patterned by a laser beam to form an etching mask (3e). At this time, it is preferable to remove not only the masking film 3 but also at least a part of the underlayer 9 and the protective layer 2 by laser, and it is more preferable to remove a part of the metal member 1. As a result, similarly to the case of the first embodiment, at least a pattern having the same shape as the pattern formed on the masking film 3 on the surface of the protective layer 2 or the protective layer 2 and the metal member 1 is precisely marked. Etching can be performed more efficiently (3f). Etching can be performed in the same manner as in the first embodiment.

It is preferable that the covering layer 7 is formed in the recess 5 for the same reason as in the first embodiment.
g). Further, the coloring layer 8 may be formed in the concave portion 5 as shown in FIG. The constituent materials, film properties, forming methods, and the like of the coating layer 7 and the coloring layer 8 are the same as those in the first embodiment.

Finally, the masking film 3 and the underlayer 9 are removed to obtain the metal member of the present invention (3h). The method of removing the masking film 3 and the underlayer 9 is the same as in the first embodiment.

By performing the above-described surface treatment, a protective layer is formed on the surface of the metal member, and a concave portion having a predetermined pattern is formed on the metal member. The metal member of the present invention formed by irradiation and completed by etching is manufactured.

Examples of the metal member include interior parts such as ornaments, exterior articles, watch exterior parts such as watch cases, watch bands, dials, ornaments such as tie pins, cufflinks, brooches, lighters, glasses, and golf clubs. Sports equipment, nameplates, panels, trophy cups, various equipment parts including housings, various containers, etc., and among them, watch exterior parts are preferable. Watch exterior parts are required to have a beautiful appearance as a decorative product, and as a practical product, visibility, denseness and corrosion resistance of a pattern formed on a metal surface are required. According to the surface treatment method, all of these requirements can be satisfied.

The surface treatment method of the metal member and the metal member have been described with reference to the illustrated embodiments, but the present invention is not limited to these embodiments. For example, the coloring layer 8 may be partially formed in the recess 5.

The underlayer 9 may be composed of a plurality of layers. Furthermore, it is not necessarily removed after etching, and may be maintained on the surface of the metal member together with the protective layer.

[0105]

Next, specific examples of the present invention will be described.

1. Surface treatment of metal member (Example 1) First, the surface of a metal member 1 made of Bs (brass) was polished to form a protective layer 2 on the surface (1a,
1b).

Next, a Cu plating layer (thickness: 3 μm) was laminated as a protective layer 2 from the side in contact with the metal member 1, and an Au plating layer (thickness: 3 μm) was laminated thereon.

On the Au plating layer constituting the protective layer 2,
Using an acrylic resin (“AM-2” manufactured by Shimizu Corporation), a masking film 3 having a thickness of 20 μm was formed by electrodeposition coating (1c). For electrodeposition coating, liquid temperature: 25 ° C, voltage:
The test was performed under the conditions of 50 V, processing time: 2 minutes, and baking: 180 ° C. × 40 minutes.

Next, the masking film 3 was processed into a predetermined pattern by using a YAG laser to form an etching mask. At this time, a part of the metal member 1 was also removed, and a concave pattern having a depth of 10 to 20 μm was formed (1d). The processing conditions with the YAG laser were: energy intensity: 13 W, frequency: 4 kHz, current: 13 A, scan speed: 50 m / s.

Further, the metal member 1 was etched by shower etching to form a concave portion 5 having a predetermined pattern (1e). The etching conditions were: etching solution: ferric chloride solution, liquid temperature: 30 ° C., processing time: 10 minutes, and the depth of the concave portion 5 of the metal member 1 was 400 μm.

In the recess 5 formed by etching,
A coating layer 7 made of an Au plating layer having a thickness of 2 μm was formed (1f).

Further, a black chrome plating film (black) having a film thickness of 1 μm was formed as a colored layer 8 in the concave portion 5 by electrolytic plating. (Econochrome BK, manufactured by Japan Metal Finishing Co., Ltd.) was used as a plating solution.

Table 2 shows the plating conditions and the like.

Finally, the metal member 1 was immersed in a stripping solution to remove the masking film 3 (1 g). A hydrocarbon solution “Neoriver 635” was used as a stripping solution, and the processing conditions were a solution temperature of 20 ° C. and a dipping time of 10 minutes.

Tables 1 and 2 show the processing conditions and the like in each step.

[0116]

[Table 1]

[0117]

[Table 2]

Example 2 The surface of a metal member 1 made of Bs (brass) was polished to form a protective layer 2 on the surface (3a, 3b). The protective layer 2 was formed by laminating two thin films of a Cu plating layer (thickness: 3 μm) and a Pd plating layer (thickness: 3 μm) from the side in contact with the metal member 1.

Next, an Au strike plating layer (Au St.) having a thickness of 0.1 μm was provided as an underlayer 7 (adhesion strengthening layer) (3c). Table 1 shows the conditions for forming the underlayer 7.

A masking film 3 (thickness: 20 μm) was formed on the underlayer 9 in the same manner as in Example 1.
d).

Next, the masking film 3 was processed into a predetermined pattern using a YAG laser to form an etching mask. At this time, a part of the metal member 1 was also removed, and a concave pattern having a depth of 10 to 20 μm was formed (3).
e). The processing conditions using the YAG laser are the same as in the first embodiment.

Further, the metal member 1 was etched by shower etching to form a concave portion 5 having a predetermined pattern (3f). As shown in Table 2, the etching conditions were as follows: etching solution: ferric chloride solution, solution temperature: 30 ° C., processing time:
After 10 minutes, the depth of the concave portion 5 of the metal member 1 was 400 μm.

A coating layer 7 made of a Pd plating layer having a thickness of 2 μm was formed in the recess 5 (3 g). Further, a black chromium plating film (black) having a film thickness of 1 μm was formed as the colored layer 8 in the same manner as in Example 1.

Finally, after removing the masking film 3 in the same manner as in Example 1, the underlayer 9 was removed by immersion in a stripping solution. For removing the underlayer 9, a cyan solution (trade name: "Enstrip Immersion Liquid") was used as an immersion liquid, and the liquid temperature was 60 ° C. and the immersion time was 2 minutes.

Tables 1 and 2 show other processing conditions and the like in each step.

(Comparative Example 1) First, as shown in FIG.
The pattern printing 12 was provided on the surface of the metal member made of (4a, 4b). Next, after applying a mask plating 13 made of Au having a film thickness of 2 μm (4c), the pattern print 12 was peeled off (4d) to form an etching mask.

Further, the metal member was etched by the shower etching method to form a pattern including the concave portions 14. The etching conditions were an etching solution: a ferric chloride solution, a liquid temperature: 30 ° C., and a processing time: 2 minutes, and the depth of the concave portion 14 formed in the metal member was 30 μm.

After a Pd plating layer having a thickness of 2 μm is formed as a coating layer 16 in the recess 14 (4e), the mask plating 13 is formed.
Was removed (4f) to produce a metal member. The removal of the mask plating was performed by immersing in a cyan solution (60 ° C. × 10 minutes).

Table 3 shows the processing conditions and the like in each step.

[0130]

[Table 3]

(Comparative Example 2) A laser beam was directly applied to the surface of a metal member made of Bs to form a concave portion having a predetermined pattern with a depth of 50 µm. The thickness of the concave portion is 2 μm as in Comparative Example 1.
A Pd plating layer of m was formed to produce a metal member.

Table 3 shows the laser processing conditions and the like.

2. Quality Evaluation For each metal member (50 each) produced in Examples 1 and 2 and Comparative Examples 1 and 2, the appearance (the state of the surface and the concave portions) was evaluated by visual observation and microscopic confirmation. Table 4 shows the evaluation items and the evaluation results. In each evaluation item, the following status was determined to be "non-defective" and displayed in three levels.

：: The non-defective rate exceeds 90% Δ: The non-defective rate is 50 to 90% ×: The non-defective rate is less than 50% Three-dimensional pattern All three-dimensional patterns clearly show unevenness.

Depression at the boundary of the depressed portion No depressed portion is found at the periphery of the depressed portion.

Etching of portions other than the concave portions is not observed at all.

The surface is not roughened by removing the mask (stripping solution).

The burrs at the boundaries of the concave portions are not observed at all.

Pattern accuracy of concave portion A pattern having the same shape as the mask shape is formed.

[0140]

[Table 4]

The metal parts of Examples 1 and 2 were:
An elaborate and three-dimensional pattern was formed on the surface. In addition, no burrs or burrs were observed at the periphery of the pattern (concave portion), and a metal member having high aesthetics was obtained.

Further, since no etching was observed in portions other than the concave portions, it was found that the masking film was in good contact. On the other hand, the masking film could be easily and completely removed, and the surface of the metal member was not rough.

On the other hand, in the metal member of Comparative Example 1, the mask plating at the edge portion was not perfect, and etching was observed at portions other than the concave portions. In addition, due to the fins of the pattern printing, fins due to poor etching were observed at the periphery of the concave part,
The patterning accuracy was poor. In addition, the surface of the metal member was rough due to removal of the etching mask.

The metal member of Comparative Example 2 had a shallow concave portion and was poor in three-dimensional appearance. The heat generated by the irradiation of the laser beam caused burrs and burrs on the periphery of the pattern, impaired the appearance, and caused spots due to heat. The patterning accuracy was poor due to the variation in diameter.

[0145]

As described above, according to the method for treating the surface of a metal member of the present invention, it is possible to easily and quickly form a clear and three-dimensional concave pattern without burrs or burrs. Further, since the mask is formed by patterning with a laser beam, a pattern can be accurately provided on the surface of a metal member having a complicated shape, and the degree of freedom in design is large. Further, the steps can be simplified, and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a surface treatment method for a metal member of the present invention.

FIG. 2 is a sectional view showing an embodiment in which a colored layer is provided on the metal member of the present invention.

FIG. 3 is a cross-sectional view illustrating a second embodiment of the surface treatment method for a metal member according to the present invention.

FIG. 4 is a cross-sectional view illustrating a comparative example of a surface treatment method for a metal member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal member 2 Protective layer 3 Masking film 5, 14 Depression 7 Coating layer 8 Coloring layer 9 Underlayer 12 Pattern printing 13 Mask plating 16 Coating layer

Claims (40)

[Claims] A step of forming a protective layer on a surface of the metal member; a step of forming a masking film on the protective layer; a step of patterning at least the masking film by irradiating a laser beam; Etching the metal member using a masking film. 2. The method according to claim 1, wherein the protective layer is a corrosion-resistant layer that imparts at least corrosion resistance to the metal member. 3. The surface treatment method for a metal member according to claim 1, wherein the protective layer is composed of two or more different thin films. 4. The method according to claim 1, wherein the protective layer is formed by plating. 5. The surface treatment method for a metal member according to claim 1, wherein said protective layer has a thickness of 0.5 to 30 μm. 6. The surface treatment method for a metal member according to claim 1, wherein at least a part of the protective layer is removed together with the masking film by the laser beam. 7. The surface treatment method for a metal member according to claim 1, wherein said protective layer and a part of said metal member are removed together with said masking film by said laser beam. 8. The surface treatment method for a metal member according to claim 1, wherein the masking film is formed by electrodeposition coating. 9. The film thickness of the masking film is 10 to 30.
The method for treating a surface of a metal member according to claim 1, wherein the thickness is μm. 10. The surface treatment method for a metal member according to claim 1, wherein a depth of the concave portion formed in the metal member by the etching is 20 μm or more. 11. The method according to claim 1, wherein the etching is wet etching. 12. The method according to claim 11, wherein the etching is shower etching. 13. The surface treatment method for a metal member according to claim 1, wherein a coating layer is formed in the recess. 14. The surface treatment method for a metal member according to claim 1, wherein a colored layer is formed in the concave portion. 15. The surface treatment method for a metal member according to claim 1, wherein the metal member is a watch exterior part. 16. A step of forming a protective layer on a surface of a metal member, a step of forming at least one underlayer on the protective layer, a step of forming a masking film on the underlayer, A step of patterning at least the masking film by irradiating the masking film; and a step of etching the metal member using the patterned masking film. 17. The method according to claim 16, wherein the protective layer is a corrosion-resistant layer that imparts at least corrosion resistance to the metal member. 18. The surface treatment method for a metal member according to claim 16, wherein the protective layer is composed of two or more different thin films. 19. The method according to claim 16, wherein the protective layer is formed by plating. 20. The protective layer has a thickness of 0.5 to 30 μm.
The surface treatment method for a metal member according to any one of claims 16 to 19, wherein 21. The surface treatment method for a metal member according to claim 16, wherein the underlayer is an adhesion reinforcing layer for improving the adhesion of the masking film. 22. The method according to claim 21, wherein the adhesion reinforcing layer is formed by wet plating or dry plating. 23. The surface treatment method for a metal member according to claim 21, wherein the adhesion reinforcing layer is made of Au or an Au-based alloy thin film. 24. The surface treatment method for a metal member according to claim 21, wherein the thickness of the adhesion reinforcing layer is 1 μm or less. 25. The method according to claim 16, wherein at least a part of the protective layer is removed together with the masking film by the laser beam. 26. The surface treatment method for a metal member according to claim 16, wherein the laser beam removes a part of the protection layer and the metal member together with the masking film. 27. The method according to claim 16, wherein the masking film is formed by electrodeposition coating. 28. The thickness of the masking film is 10 to 3
The surface treatment method for a metal member according to any one of claims 16 to 27, wherein the thickness is 0 µm. 29. The method according to claim 16, wherein the etching is wet etching. 30. The method according to claim 29, wherein the etching is shower etching. 31. The recess formed in the metal member by the etching has a depth of 20 μm or more.
31. The surface treatment method for a metal member according to any one of claims 30 to 30. 32. The surface treatment method for a metal member according to claim 16, wherein a coating layer is formed in the concave portion. 33. The surface treatment method for a metal member according to claim 16, wherein a colored layer is formed in the concave portion. 34. The surface treatment method for a metal member according to claim 16, wherein the metal member is a watch exterior part. 35. A metal member having a predetermined pattern of concave portions formed on a surface thereof, wherein a protective layer is formed on a surface of the metal member, and the concave portion is partially formed by laser light irradiation, and is etched. A metal member characterized by being completed. 36. The protective layer has a thickness of 0.5 to 30 μm.
36. The metal member according to claim 35, wherein: 37. The metal member according to claim 35, wherein a depth of the concave portion formed in the metal member is 20 μm or more. 38. The metal member according to claim 35, wherein a coating layer is formed in the recess. 39. The metal member according to claim 35, wherein a colored layer is formed in the concave portion. 40. The metal member according to claim 35, wherein the metal member is a watch exterior part.