阅读说明：本技术 硬质装饰构件及其制造方法 (Hard decorative member and method for manufacturing same ) 是由 吉田陆人 于 2019-06-10 设计创作，主要内容包括：本发明提供一种具有淡粉红色系的金色的硬质装饰构件。本发明的硬质装饰构件的特征在于,在钛或母材表面形成有钛的基材上具有通过干式镀覆法成膜的金合金层,其具备：基底层,形成在基材上且由碳氮化钛构成；密合层,形成在基底层上且含有碳氮化钛以及金、铜和钯；以及,金合金层,形成在密合层上且含有金、铜和钯,其中,金合金层含有金70.3～75.2重量％、铜20.7～25.6重量％、钯3.7～4.3重量％。(The invention provides a hard decorative member having a pale pink color and a gold color. The hard decorative member of the present invention is a hard decorative member having a gold alloy layer formed by a dry plating method on a base material having titanium or a base material surface formed with titanium, the hard decorative member including: a base layer formed on the base material and composed of titanium carbonitride; an adhesion layer formed on the base layer and containing titanium carbonitride, gold, copper, and palladium; and a gold alloy layer formed on the adhesion layer and containing gold, copper and palladium, wherein the gold alloy layer contains 70.3 to 75.2 wt% of gold, 20.7 to 25.6 wt% of copper and 3.7 to 4.3 wt% of palladium.)

1. A hard decorative member having a gold alloy layer formed by a dry plating method on a base material having titanium or formed on the surface of a base material, comprising:

A base layer formed on the base material and composed of titanium carbonitride,

An adhesion layer formed on the base layer and containing titanium carbonitride, gold, copper, and palladium, and

A gold alloy layer formed on the adhesion layer and containing gold, copper, and palladium,

Wherein the gold alloy layer contains 70.3 to 75.2 wt% of gold, 20.7 to 25.6 wt% of copper, and 3.7 to 4.3 wt% of palladium.

2. The hard decorative member according to claim 1, wherein a vickers hardness in a layer structure of the gold-alloy layer composed of the base layer, the adhesion layer, and the gold-alloy layer is 700 or more and 800 or less.

3. The hard decorative member according to claim 1 or 2, wherein a color of the gold alloy layer based on a laabb color system is evaluated in a range of 84.6 ≦ lab ≦ 85.4, 5.9 ≦ lab ≦ 6.1, 10.3 ≦ b ≦ 10.6.

4. The hard decorative member according to any one of claims 1 to 3, wherein the base layer has a Vickers hardness of 2100 or more and 2400 or less.

5. The hard decorative member according to any one of claims 1 to 4, wherein the base layer contains 65.3 to 69.5 wt% of titanium, 4.9 to 5.9 wt% of carbon, and 25.6 to 29.9 wt% of nitrogen.

6. The hard decorative member according to any one of claims 1 to 5, wherein the substrate layer has a color evaluation based on a Lab system in a range of 70.6. ltoreq. L.ltoreq.73.0, 5.0. ltoreq. a.ltoreq.7.1, and 11.7. ltoreq. b.ltoreq.15.2.

7. A method for manufacturing a hard decorative member, comprising the steps of:

A base layer forming step of forming a base layer of titanium carbonitride on a base material having titanium or a base material surface on which titanium is formed,

A step of forming an adhesion layer by forming an adhesion layer containing titanium carbonitride and gold, copper and palladium on the base layer, and

And a gold alloy layer forming step of forming a gold alloy layer containing gold, copper and palladium, and containing 70.3 to 75.2 wt% of gold, 20.7 to 25.6 wt% of copper and 3.7 to 4.3 wt% of palladium on the adhesion layer.

8. The method for manufacturing a hard decorative member according to claim 7, wherein the base layer forming step forms the base layer containing 65.3 to 69.5 wt% of titanium, 4.9 to 5.9 wt% of carbon, and 25.6 to 29.9 wt% of nitrogen.

9. The method according to claim 7 or 8, wherein in the base layer forming step, the titanium is evaporated while applying a cathode voltage to the base material by introducing argon gas, nitrogen gas, and methane gas into a chamber of a vacuum apparatus.

10. The method of manufacturing a hard decorative member according to any one of claims 7 to 9, wherein in the adhesion layer forming step, an argon gas, a nitrogen gas, and a methane gas are introduced into a chamber of a vacuum apparatus, and titanium and a gold alloy containing gold, copper, and palladium are evaporated in a state where a cathode voltage is applied to the base material.

11. The method for producing a hard decorative member according to any one of claims 7 to 10, wherein in the gold alloy layer forming step, argon gas is introduced into a chamber of a vacuum apparatus, and gold alloy containing gold, copper, and palladium is evaporated in a state where a cathode voltage is applied to the base material.

Technical Field

The present invention relates to a hard decorative member having a gold alloy layer formed by a dry plating method on a substrate, and a method for manufacturing the same.

Background

Conventionally, exterior parts of watches such as watchcases and watchbands, and accessories such as eyeglass frames, rings, and necklaces are required to have a metallic appearance with a gold color of various colors. Attempts have been made to produce decorative members by forming various decorative films on a base material such as titanium or stainless steel, thereby satisfying the above requirements. Among them, a pink-red-based gold color is highly demanded, and a decorative member having a gold alloy layer formed by a dry plating method is used from the viewpoint of abrasion resistance, cost, and the like.

For example, in a gold alloy coating film laminate and a gold alloy coating member disclosed in patent document 1, a base plating layer is formed on a base material by a dry plating method, and a gold alloy coating is formed on the base plating layer, and the appearance is described to be pink.

Disclosure of Invention

However, with regard to the pink color, a decorative member having a light pink color, particularly a pink color such as a cherry blossom, has been demanded, but such a pink color cannot be expressed by the decorative member described in patent document 1. Further, the difference in color between the gold alloy coating and the base plating layer makes it impossible to maintain the aesthetic appearance when the gold alloy coating is damaged or partially damaged.

The present invention aims to provide a hard decorative member having a pale pink-based gold appearance and capable of maintaining the aesthetic appearance even after long-term use.

in order to achieve the above object, a hard decorative member according to the present invention is a hard decorative member having a gold alloy layer formed by a dry plating method on a base material having titanium or a base material surface formed with titanium, the hard decorative member including: a base layer formed on the base material and made of titanium carbonitride; an adhesion layer formed on the base layer and containing titanium carbonitride, and gold, copper, and palladium; and a gold alloy layer formed on the adhesion layer and containing gold, copper and palladium, wherein the gold alloy layer contains 70.3 to 75.2 wt% of gold, 20.7 to 25.6 wt% of copper and 3.7 to 4.3 wt% of palladium.

The gold alloy layer is characterized in that the Vickers hardness of a layer structure composed of the base layer, the adhesion layer, and the gold alloy layer is 700 to 800.

The color of the gold alloy layer based on the Lxa b system ("Lxa b system" based on the CIE system. the same applies hereinafter) was evaluated in the ranges of 84.6. ltoreq. L.ltoreq.85.4, 5.9. ltoreq. a.ltoreq.6.1, and 10.3. ltoreq. b.ltoreq.10.6.

the base layer is characterized by having a Vickers hardness of 2100 to 2400.

The underlayer is characterized by containing 65.3-69.5 wt% of titanium, 4.9-5.9 wt% of carbon, and 25.9-29.9 wt% of nitrogen.

The substrate layer is characterized in that the color evaluation based on the La b system is in the range of 70.6L 73.0, 5.0 a 7.1, 11.7 b 15.2.

The method for manufacturing a hard decorative member according to the present invention is characterized by comprising the steps of: a base layer forming step of forming a base layer of titanium carbonitride on a base material having titanium or a base material surface on which titanium is formed; a bonding layer forming step of forming a bonding layer containing titanium carbonitride and gold, copper, and palladium on the base layer; and a gold alloy layer forming step of forming a gold alloy layer containing gold, copper and palladium, and containing 70.3 to 75.2 wt% of gold, 20.7 to 25.6 wt% of copper and 3.7 to 4.3 wt% of palladium on the adhesion layer.

The base layer forming step is characterized by forming a base layer containing 65.3 to 69.5 wt% of titanium, 4.9 to 5.9 wt% of carbon, and 25.9 to 29.9 wt% of nitrogen.

the base layer forming step is characterized in that argon gas, nitrogen gas and methane gas are introduced into a chamber of a vacuum apparatus, and titanium is evaporated while applying a cathode voltage to the base material.

The step of forming an adhesion layer is characterized in that argon gas, nitrogen gas and methane gas are introduced into a chamber of a vacuum apparatus, and gold alloy containing titanium, gold, copper and palladium is evaporated while applying a cathode voltage to the substrate.

The gold alloy layer forming step is characterized in that argon gas is introduced into a chamber of a vacuum apparatus, and gold alloy containing gold, copper and palladium is evaporated in a state where a cathode voltage is applied to a substrate.

The hard decorative member of the present invention is a hard decorative member having a base material on which titanium is formed on a surface of titanium or a base material, and a gold alloy layer formed by a dry plating method, and has a structure including a base layer formed on the base material and made of titanium carbonitride, an adhesion layer formed on the base layer and containing titanium carbonitride, gold, copper, and palladium, and a gold alloy layer formed on the adhesion layer and containing gold, copper, and palladium, whereby a light pink appearance can be obtained and excellent scratch resistance can be obtained.

Drawings

Fig. 1 is a sectional view showing a hard decorative member according to an embodiment of the present invention.

fig. 2 is a sectional view showing a hard decorative member according to an embodiment of the present invention.

Fig. 3 is a process diagram showing a manufacturing method according to an embodiment of the present invention.

Fig. 4 is a process diagram showing a manufacturing method according to an embodiment of the present invention.

Fig. 5 is a table showing the characteristics of the hard decorative member according to the embodiment of the present invention.

Description of the symbols

1 base material

2 base layer

3 bonding layer

4 gold alloy layer

5 base material

6 substrate adhesion layer

10 hard decorative member

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiments described below are merely examples of the hard decorative member for embodying the idea of the present invention, and the present invention is not limited to the following configurations. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the constituent members described in the embodiments are not intended to limit the scope of the present invention to these values unless otherwise specified, and are merely illustrative examples. In the following description, the same components and the same components are denoted by the same names and symbols, and detailed description thereof may be omitted as appropriate.

The structure of the hard decorative member according to the embodiment of the present invention will be described with reference to fig. 1 and 5. FIG. 1 is a sectional view showing the structure of a hard decorative member of the present invention, and FIG. 5 is a table showing the evaluation results of examples 1 to 6 and comparative examples 1 to 2 to which the present invention is applied.

As shown in fig. 1, a hard decorative member 10 of the present invention is a hard decorative member having a gold alloy layer formed by a dry plating method on a base material having titanium or a base material surface formed with titanium, and has a structure including: a base layer 2 formed on the base material 1 and made of titanium carbonitride; an adhesion layer 3 formed on the base layer 2 and containing titanium carbonitride, gold, copper, and palladium; and a gold alloy layer 4 formed on the adhesion layer 3 and containing gold, copper, and palladium.

Further, the base layer 2 is characterized in that the color evaluation based on the laxa + b color system is in the range of 70.6 or less L + 73.0, 5.0 or less a + 7.1, 11.7 or less b + 15.2 and has a pale pink appearance, and the gold alloy layer 4 is characterized in that the color evaluation based on the laxa + b color system is in the range of 84.6 or less L + 85.4, 5.9 or less a + 6.1, 10.3 or less b + 10.6 and has a pale pink appearance.

The color tones of the base layer 2 and the gold alloy layer 4 were evaluated based on L a b chromaticity diagram, using CM-2600D manufactured by KONICA MINOLTA, Spectra Magic NX as a measurement software, and CIE standard illuminant D65 as a light source.

[ base Material ]

The substrate 1 is made of metal or ceramic. Specific examples of the metal include stainless steel, titanium alloy, copper alloy, tungsten, hardened stainless steel, titanium, and titanium alloy. These metals may be used alone or in combination of 2 or more. The shape of the substrate 1 is not limited.

In the case of using a material other than titanium as the base material 1, as shown in fig. 2, a base material having a base material adhesion layer 6 formed on the surface of the base material 5 may be used as the base material 1, and base materials 5 of various materials may be used. Titanium is formed as a base material adhesion layer 6 on the surface of the base material 5.

For example, inexpensive stainless steel is used as the base material 5, and titanium is formed as the base material adhesion layer 6 on the surface thereof.

The base material adhesion layer 6 is formed by ion plating titanium to a thickness of about 0.05 μm on the surface of the base material 5.

[ base layer ]

The underlayer 2 is a titanium carbonitride layer, and when titanium is contained in an amount of 65.3 to 69.5 wt%, carbon is contained in an amount of 4.9 to 5.9 wt%, and nitrogen is contained in an amount of 25.6 to 29.9 wt%, the underlayer 2 can be formed in a light pink color close to the color tone of the gold alloy layer 4. Further, as shown in examples 1 to 6, when titanium is contained in an amount of 67.3 to 69.0 wt%, carbon is contained in an amount of 4.9 to 5.3 wt%, and nitrogen is contained in an amount of 25.9 to 27.6 wt%, the base layer 2 having a light pink color close to the color tone of the gold alloy layer 4 can be formed. In the hard decorative member of the present invention, even if the adhesion layer 3 and the gold-alloy layer 4 on the base layer 2 are peeled off, the base layer 2 is light pink close to the gold-alloy layer 4, and therefore, the hard decorative member has an appearance with little uncomfortable feeling.

The base layer 2 having the above composition has a vickers hardness of 2100 to 2400 inclusive, has a light pink appearance, and is excellent in durability such as scratch resistance and abrasion resistance. If the base layer 2 is sufficiently harder than the base material 1, scratch resistance is improved, and the adhesion layer 3 and the gold alloy layer 4 are less likely to peel off.

The vickers hardness of the underlayer 2 was measured using HM2000XYp manufactured by FISCHER as a micro indentation hardness tester. The gauge was unloaded by holding the gauge with a load of 5mN for 10 seconds using a Vickers indenter, and the hardness was calculated from the depth of the inserted Vickers indenter.

The base layer 2 is preferably formed to have a thickness of about 0.3 μm. If the film thickness is about 0.2 μm or less, the color tone changes under the influence of the substrate 1 or the substrate adhesive layer 6, but if the film thickness is about 0.3 μm or more, the color of the base layer 2 does not change regardless of the color of the substrate 1 or the substrate adhesive layer 6.

Fig. 5 shows the results of color evaluation and composition, hardness, and appearance observation when the gold-alloy layer 4 is partially broken of the base layer 2 and the gold-alloy layer 4 of the samples of examples 1 to 6 produced by applying the present invention and the samples of comparative examples 1 to 2 produced by changing the conditions of the production method and changing the color tone of the base layer 2. The judgment of pass or fail is made by "good" indicating that the difference between the color of the base layer 2 or the adhesion layer 3 in the defective portion and the color of the gold alloy layer 4 is not visually recognized and there is no problem in appearance when the gold alloy layer 4 has a defective portion, and "x" indicating that the difference between the color of the base layer 2 or the adhesion layer 3 in the defective portion and the color of the gold alloy layer 4 is visually recognized.

The color tone of the base layer 2 is preferably close to that of the gold alloy layer 4 so that the change in appearance can be reduced even when the adhesion layer 3 or the gold alloy layer 4 on the base layer 2 is partially chipped or peeled off by scratching or the like. As shown in fig. 5, as a result of observing the appearance of the gold alloy layer 4 of the samples produced in examples 1 to 6 and comparative examples 1 to 2, the color difference between the base layer 2 and the gold alloy layer 4 was large and the color of the defective portion was visually changed, but the color difference between the base layer 2 and the gold alloy layer 4 was small and the sense of incongruity was small in examples 1 to 6, and the defective portion could not be distinguished, and therefore, the color tone of the base layer 2 was preferably in the range of 70.6L 73.0, 5.0 a 7.1, 11.7 b 15.2 based on the color evaluation of the laa b color system.

[ bonding layer ]

The adhesion layer 3 is a mixture of the base layer 2 (titanium carbonitride) and the gold alloy layer 4 (gold, copper, and palladium), and is provided between the base layer 2 and the gold alloy layer 4, whereby the adhesion between the base layer 2 (titanium carbonitride) and the gold alloy layer 4 (alloy containing gold, copper, and palladium) which are different materials can be improved. This can prevent the gold-alloy layer 4 from peeling off, and can improve the performance qualities such as scratch resistance and wear resistance.

The adhesion layer 3 is preferably formed at a thickness of about 0.05 μm. If the film thickness is about 0.05 μm, the effect of improving the adhesion can be secured, and if the film thickness is excessively thick, the amount of noble metal used increases, which is not preferable because the cost increases.

[ gold alloy layer ]

The gold alloy layer 4 is made of gold alloy (gold, copper, and palladium), and the color tone thereof preferably shows pale pink-red gold, and as a result of observing the gold alloy layers 4 of examples 1 to 6 and comparative examples 1 to 2 of fig. 5, a pink beautiful appearance like cherry blossom is obtained in all samples, and therefore, the color evaluation based on the laa b color system is more preferably in the ranges of 84.6L 85.4, 5.9 a 6.1, and 10.3 b 10.6.

In addition, in order to obtain the pale pink gold color, the composition of the gold alloy layer 4 contains 70.3 to 75.8 wt% of gold, 20.0 to 25.6 wt% of copper, and 3.7 to 4.4 wt% of palladium, and preferably contains 70.3 to 75.2 wt% of gold, 20.7 to 25.6 wt% of copper, and 3.7 to 4.3 wt% of palladium, and in examples 1 to 6 of fig. 5 using the composition in this range, a hard decorative member having a vickers hardness of 700 or more and 800 or less in a layer structure composed of the base layer 2, the adhesion layer 3, and the gold alloy layer 4 can be formed, and the hard decorative member is excellent in scratch resistance and abrasion resistance, and the appearance of the pale pink gold color can be obtained.

vickers hardness of the layer structure composed of the base layer 2, the adhesion layer 3, and the gold alloy layer 4 was measured by using HM2000XYp manufactured by FISCHER as a micro indentation hardness tester. The gauge was unloaded by holding the gauge with a load of 5mN for 10 seconds using a Vickers indenter, and the hardness was calculated from the depth of the inserted Vickers indenter.

if the thickness of the gold-alloy layer 4 is too large, the amount of noble metal used increases, and the cost increases, and therefore, the thickness is preferably about 0.1 μm. If the film thickness is about 0.1 μm, the gold-alloy layer 4 can be obtained with a uniform color tone over the entire surface of the substrate 1.

As described above, the hard decorative member of the present invention includes the following layers: a base layer 2 formed on the base material 1 and made of titanium carbonitride; an adhesion layer 3 formed on the base layer 2 and containing titanium carbonitride, gold, copper, and palladium; and a gold-alloy layer 4 formed on the adhesion layer 3 and containing gold, copper, and palladium; the color evaluation of the base layer 2 based on the laxa color system is in the range of 70.6L 73.0, 5.0 a 7.1, 11.7 b 15.2 and has a pale pink appearance, and the color evaluation of the gold alloy layer 4 based on the laxa color system is in the range of 84.6L 85.4, 5.9 a 6.1, 10.3 b 10.6 and has a pale pink appearance, so that a pink appearance like a flower of cherry blossom can be obtained, and even when the gold alloy layer 4 is partially broken and the base layer 2 is exposed, the color difference between the gold alloy layer 4 and the base layer 2 is small, and the sense of incongruity in appearance can be reduced.

Further, the base layer 2 of the hard decorative member of the present invention has a hardness of 2100 to 2400 vickers hardness, and the vickers hardness of the layer structure composed of the base layer 2, the adhesion layer 3, and the gold-alloy layer 4 is 700 to 800, so that the hard decorative member has sufficient hardness as a decorative member, and can be obtained that has excellent durability such as scratch resistance and wear resistance.

[ method for producing hard decorative Member ]

Next, a method for manufacturing a hard decorative member according to an embodiment of the present invention will be described with reference to the process diagram of fig. 3. The method for manufacturing a hard decorative member of the present invention comprises the steps of: a preparation step S1 of installing the evaporation material and the substrate 1 in the chamber of the vacuum apparatus; a base layer forming step S2 of forming titanium carbonitride as a base layer 2; an adhesion layer forming step S3 of forming an adhesion layer 3 containing titanium carbonitride, gold, copper, and palladium; and a gold-alloy layer forming step S4 of forming a gold-alloy layer 4 containing gold, copper, and palladium.

[ preparation Process S1]

The preparation step S1 is a step of: in a chamber of a vacuum apparatus, titanium and a gold alloy (an alloy of gold, copper and palladium) as evaporation materials were placed in different crucibles, respectively, a base material 1 made of titanium or having titanium formed on the surface of the base material was mounted on a holder, and the chamber of the vacuum apparatus was evacuated to about 4.0X 10^-3Pa。

by exhausting gas to 3.0X 10 in the preparation step S1^－3Pa～5.0×10^－3Pa reduces the residual gas in the chamber, and reduces the influence of the residual gas on the hue in the base layer forming step S2 and the gold alloy layer forming step S4. If the degree of vacuum is further increased, residual gas is generatedThe volume is further reduced, but even if the pressure is further reduced, the influence on the color tone is not much changed, and the exhaust time is rather prolonged.

[ base layer Forming Process S2]

The base layer forming step S2 is a step of: argon gas at about 190cc/min, nitrogen gas at about 100cc/min, and methane gas at about 50cc/min were introduced into a chamber of a vacuum apparatus, a cathode voltage of 10V was applied to the substrate 1, and then an evaporation material (titanium) placed in a crucible was irradiated with an electron beam to evaporate the electron beam, and ion plating was performed for about 30 minutes while maintaining a vacuum degree at about 0.2Pa, thereby forming the underlayer 2 of titanium carbonitride on the substrate 1.

[ bonding layer Forming step S3]

The adhesion layer forming step S3 is a step of: after the base layer forming step S2, the adhesion layer 3 including titanium carbonitride and an alloy of gold containing gold, copper, and palladium was formed on the base layer 2 by performing ion plating for about 1 minute by irradiating an evaporation material (gold alloy containing gold, copper, and palladium) with an electron beam while maintaining argon gas at about 190cc/min, nitrogen gas at about 100cc/min, and methane gas at a flow rate of about 50cc/min into a chamber of a vacuum apparatus and irradiating the evaporation material (titanium) provided in a crucible with an electron beam.

[ gold alloy layer Forming step S4]

The gold-alloy-layer forming step S4 is a step of: after the adhesion layer forming step S3, the irradiation of the electron beam to titanium as an evaporation material provided in the crucible was stopped, the introduction of nitrogen gas and methane gas was stopped, argon gas was introduced into the vacuum chamber at a flow rate of about 280cc/min, and ion plating was performed for 5 minutes to form the gold alloy layer 4 on the adhesion layer 3.

In order to stabilize the plasma density and the evaporation amount of the evaporation material in the range of about 0.1 to 0.5Pa in which the plasma can be sufficiently maintained, the degree of vacuum at the time of film formation is preferably made constant in the underlayer forming step S1, the adhesion layer forming step S2, and the gold alloy layer forming step S3.

In the base layer forming step S2 and the adhesion layer forming step S3, the color tone of the base layer 2 can be obtained by introducing nitrogen gas into the vacuum chamber at a flow rate of about 100cc/min and methane gas at a flow rate of about 50cc/min, and if the nitrogen gas is increased or the methane gas is decreased relative to the gas amount, the color tone of titanium carbonitride will approach the yellow-based gold color of titanium nitride, whereas if the nitrogen gas is decreased or the methane gas is increased, the color tone of titanium carbonitride will approach the gray-based gold color of titanium carbide. In addition, in order to maintain the plasma and keep the degree of vacuum constant, argon gas is flowed into the vacuum chamber at a flow rate in each of the base layer forming step S2, the adhesion layer forming step S3, and the gold alloy layer forming step S4.

If the cathode voltage during film formation is less than 10V, sufficient adhesion, abrasion resistance, and color tone cannot be obtained from the ion plating method close to the vacuum deposition method, and if it is more than 30V, although adhesion can be further improved, the frequency of discharge that causes adverse effects during film formation increases, and therefore, it is preferable to set it within the range of 10V to 30V that can ensure sufficient adhesion.

[ Process for Forming bonding layer of base Material S1' ]

In the case where the base material 1 is made of a material other than titanium, as shown in the process diagram of fig. 4, a base material adhesion layer forming step S1' of forming the base material adhesion layer 6 on the surface of the base material 5 is performed between the preparation step S1 and the base layer forming step S2, and materials of various materials can be used as the base material 1.

The base material adhesion layer forming step S1' is a step of: after the preparation step S1, argon gas was introduced into the vacuum chamber at a flow rate of about 280cc/min, and the evaporation material (titanium) placed in the crucible was evaporated by irradiation of an electron beam while maintaining a state in which a cathode voltage of 10V was applied to the base material 5, and ion plating was performed for 3 minutes to form the base material adhesion layer 6 made of pure titanium. The gas flow rate and the ion plating time are merely illustrative examples, and are not limited to the description of the embodiments.

As described above, the hard decorative member and the method for producing the same according to the present invention can provide the exterior member for a watch having the gold alloy layer of pale pink gold.

Further, by matching the composition and color tone of the base layer 2 with the gold alloy layer 4 having a pale pink-red gold color, the sense of incongruity is reduced and inconspicuous even if the gold alloy layer 4 is partially scratched.

Further, since the hardness of titanium carbonitride in the underlayer 2 is high, the base material is not exposed even if the base material is partially scratched, and a hard decorative member having excellent scratch resistance and wear resistance can be provided.