KR20010038852A - Method of Producing a Gold Colored Hard Coating Film for Decoration - Google Patents

Abstract

PURPOSE: A method for preparing a gold colored rigid film for decoration is provided in which high abrasion resistant gold colored rigid plating having a bright color is manufactured despite of the increase of the plating thickness by alternately forming a Ti layer and a TiN layer having appropriate thickness or alternately forming a Ti layer and a TiCN layer using an existing sputtering method. CONSTITUTION: In a decorative gold colored rigid plating, the method for preparing a gold colored rigid film for decoration comprises the processes of forming even numbered layers of the second layer or above as a TiN rigid layer or a TiCN rigid layer after forming a first layer as a Ti cohered layer on a material; and odd numbered layers of the third layer or above as a Ti intermediate layer so that the alternation of the rigid layer and the intermediate layer is carried out more than once, and the alternation of the rigid layer and the intermediate layer is terminated in such a manner that the rigid layer is finally alternated.

Description

Method of Producing a Gold Colored Hard Coating Film for Decoration}

The present invention relates to a method of forming a decorative hard film such as titanium nitride (TiN) or titanium carbonitride (TiCN) by vacuum sputtering, and more particularly, by alternately plating titanium (Ti) and TiN or TiCN. The present invention relates to a method for producing a gold hard film having a multilayer structure.

Ti, a Group IV element of the periodic table, has excellent corrosion resistance, and TiN, Ti nitride and carbonitride, TiCN, are similar in color to gold and have high hardness and are excellent in abrasion resistance. Therefore, Ti, TiN or TiCN is plated under vacuum. Sputtering and arc ion plating technology has recently been applied to gold hard plating for decorative products such as watch parts, accessories, water-receiving products, bathroom items, kitchen utensils and hinges.

Among these gold hard plating methods, arc ion plating applies a relatively large current of 50 to 150 amperes to an arc source of a titanium plate in a vacuum atmosphere to generate a discharge, thereby plating particles on the surface of the product that protrude from the arc source. Although there is an advantage in that the plating layer is high and the density of the plating layer is high, when the arc source causes an abnormal discharge, large particles of a few microns in diameter are attached to the surface of the product, and the aesthetic quality may be degraded by milky plating.

On the other hand, the sputtering method is a method of plating the particles to the surface of the product by colliding gas particles such as argon to the metal target (cathode) of the titanium plate under vacuum, the particle size to be plated is fine in angstrom unit, In particular, when the alloy plating is easy to control the components of the plating layer, it is known as a plating method suitable for decorative products in which the uppermost layer is plated with a gold alloy on the gold hard plated layer.

However, the sputtered TiN or TiCN thin film has a disadvantage of high surface roughness, that is, low surface density, so that L * a * b *, which is the brightness value among the CIE color coding methods, is weak. It has a low characteristic to be applied to decorative products in the range of 72 to 78. Meanwhile, in the plating process of sputtered TiN or TiCN, as shown in FIG. 1, nuclei are formed on the surface at the initial stage of the plating, and fine crystals grow on the nuclei, and finally grow to columnar crystals. It is known that the growth rate of the columnar column is because the growth rate varies depending on the crystal direction, the acid region selectively grows faster, and the valley region grows slowly due to the shading effect.

This columnar coating film exhibits a characteristic of high surface area and low surface density in the microscopic structure, and thus high surface roughness. Since the sputtered TiN or TiCN is darker in color and becomes darker when fingerprints are deposited, it is important to increase the CIE L * value of the plating.

The CIE L * value required for decorative gold hard plating is in the range of about 82 to 87, and plating below this range is dark and difficult to apply to high quality aesthetic products.

Recently, a method of increasing the L * value has been proposed to increase the bias voltage applied to an object to be plated when sputtering or to use nitride or carbonitride of zirconium or titanium-aluminum alloy instead of titanium.

However, when the bias voltage is increased during sputtering, there is an advantage that the grown plating crystal becomes fine and the purity is high, but to increase the L * value to 82 to 85, a high bias voltage of 1000 to 2000 volts must be applied. Sputtering under such a high bias voltage is very difficult to apply to decorative products because the stress of the plating layer is very large, the plating speed is also very small and the frequency of arcing on the surface of the product is high.

In addition, the plating of nitrides or carbonitrides of zirconium or titanium-aluminum alloys instead of titanium is difficult to express a color similar to gold and has a disadvantage in that the plating cost is increased because the material is five times more expensive than titanium.

As described above, the conventional decorative gold hard plating has a problem according to its manufacturing method, and more recently, there is an increasing demand for increasing the plating thickness to about 1 micron or more in order to improve the service life of the product.

Accordingly, the present inventors have repeatedly studied and experimented to solve the above problems and obtain a light-hard gold hard plating, and the present invention has been proposed based on the results. By alternately forming a Ti layer and a TiN layer, or by alternately forming a Ti layer and a TiCN layer, to provide a method of producing a high wear resistance gold hard plating with bright colors even when the plating thickness is increased. There is this.

1 is a schematic diagram showing the growth process of the plating layer by the sputtering method

2 is a structural diagram showing a sputtering plating layer according to the present invention

3 is a structural diagram showing a conventional gold hard plating layer

In the present invention for achieving the above object in the decorative gold hard plating, the first layer on the material is formed of a Ti adhesion layer, the second or more even layers are formed of a TiN hard layer or TiCN hard layer, the third layer The above odd-numbered layer is formed of a Ti intermediate layer so that the hard layer and the intermediate layer are alternately performed one or more times, and the hard layer and the intermediate layer are finished at the last with the hard layer. It is about.

Hereinafter, the present invention will be described in detail.

The multi-layer gold hard plating according to the present invention is characterized by consisting of one Ti adhesion layer, two or more TiN hard layers or TiCN hard layers, and one or more Ti intermediate layers, and may additionally form one gold plating layer. .

The Ti adhesion layer serves to increase adhesion between the material and the TiN hard layer or the TiCN hard layer, which is the first plating layer, and to reduce the stress. The Ti adhesion layer is preferably plated to have a thickness of about 0.1 to 0.3 microns (μ), which tends to reduce the plating stress relaxation effect when the thickness of the Ti adhesion layer is less than about 0.1 μ. This is because the surface roughness of the plating becomes larger when the plating color becomes darker.

In addition, the TiN hard layer or TiCN hard layer is a second or more even layer, the thickness is preferably plated so that the thickness is about 0.1 ~ 0.3μ, which is when the thickness of the TiN hard layer or TiCN hard layer is less than about 0.1μ This is because the wear resistance tends to be lowered, and when it exceeds about 0.3 mu, the surface roughness of the plating increases and the plating color tends to be dark. In the present invention, the number of layers of the TiN hard layer or the TiCN hard layer required according to the total plating thickness required can be increased.

In addition, the Ti intermediate layer is a third or more odd layer, and the plating is preferably performed so that the thickness is about 0.03 to 0.1 μ, which is discontinuous when the thickness of the Ti intermediate layer is less than about 0.03 μ. The TiN hard layer or the TiCN hard layer grows continuously, and the plating color becomes dark. When the TiN hard layer exceeds about 0.1 μ, the plating is soft because of the low hardness of the metal. In the present invention, it is possible to increase the number of layers of the Ti intermediate layer required according to the required total plating thickness.

In the present invention, the hard layer and the intermediate layer are alternately formed, and then gold plating may be finally performed in order to obtain a plating surface closer to gold. Such gold plating serves to give a color to the product, the thickness is preferably plated so that the thickness is about 0.05μ or more, various kinds of gold alloy plating may be applied according to the requirements of the decorative parts, and also the electroplating method on the gold plating layer Coloring plating can be done in various colors.

In the following, a method of obtaining the plating layer as described above will be described with more specific examples.

The manufacturing method according to the present invention is characterized by obtaining Ti, TiN or TiCN in a multi-layered structure without changing the conventional sputtering method to obtain a decorative gold hard alloy with bright colors and excellent wear resistance.

An example of a manufacturing method according to the present invention will be described with reference to FIG. 2. After attaching the target made of Ti plate and the target made of Au alloy to the sputtering device, load the object to be plated, operate the vacuum exhaust pump to depressurize the device, and introduce argon (Ar) gas into the device. First, as shown in FIG. 2, Ti is sputtered to have a thickness of about 0.1 to 0.3 mu as the first layer. Subsequently, nitrogen (N ₂ ) and acetylene (C ₂ H ₂ ) gases are introduced into the apparatus to sputter TiCN to a thickness of about 0.1 to 0.3 mu in the second layer. In the case of TiN, N ₂ is introduced into the device.

Next, the introduction of nitrogen and acetylene was stopped, and Ti was sputtered to a thickness of about 0.03 to 0.1 mu in the third layer in an atmosphere where only argon was present in the apparatus. Subsequently, the TiN hard layer or the TiCN hard layer and the Ti intermediate layer are sputtered alternately so as to have a predetermined thickness so that the final layer becomes the TiN hard layer or the TiCN hard layer, and if necessary, the thickness of the gold alloy is about 0.05 μm or more. Sputter as much as possible.

Hereinafter, the present invention will be described in detail through examples.

Example

The stainless steel watch case was degreased, washed and dried, and loaded into a German Rivault ZV1200 continuous vacuum sputtering apparatus. The cathode inside the apparatus was previously equipped with a Ti target of 99.5% purity and a gold alloy target having a size of 748 * 88 * 6mm. The vacuum pump was then operated to evacuate the vacuum in the apparatus to 5 × 10 ⁻⁶ mbar. Then, sputtering was performed under the same conditions as in Table 1 (Invention Example 1) and Table 2 (Invention Example 2).

The CIE L * a * b * of the plating layer prepared by the above method was measured twice, and the results are shown in Table 3 below. In addition, when only 0.2 micrometer Ti layer and 0.6 micrometer TiCN layer were formed by the sputtering method (comparative example 1), and when only 0.2 micrometer Ti layer and 1.2 micrometers TiCN layer were formed by the sputtering method (comparative example) 2) and 0.2 µ Ti layer and 0.6 µ TiCN layer were formed by the arc ion plating method (Comparative Example 3), and 0.2 µ Ti layer and 1.2 µ TiCN by the arc ion plating method. In the case of forming a layer (Comparative Example 4), CIE L * a * b * was also measured and the results are shown in Table 3 below.

As can be seen from the CIE L * a * b * measurement results shown in Table 3, in the case of Comparative Example (1) which is a conventional sputtering method showing a plated layer structure as shown in FIG. As the TiCN thickness increases, the L * value decreases as in Comparative Example (2), and the color becomes darker. Comparative Example (3,4) is a plating color produced by the arc ion plating method, which is different from the sputtering method, and the L * value is 84 to 85, which gives a feeling of overall blur because of bright colors or abnormally large particles.

On the contrary, in the case of Inventive Example (1) prepared according to the conditions of the present invention, the L * value was about 85, and a bright gold color was shown. In the Inventive Example (2), even when the thickness of the TiN hard layer was increased, L * The value was about 85, so that a hard gold plated layer having excellent abrasion resistance was formed.

As described above, according to the present invention, it is possible to form a bright gold Ti / TiN or Ti / TiCN multilayer plating while applying a conventional sputtering method, and even if the number of layers is increased, the L * value is high and the wear resistance is not deteriorated. You can do a healthy plating. For this reason, the decorative product manufactured by this invention has the effect which can exhibit high reliability, such as extending a plating life.

Claims (3)

In decorative gold hard plating, After the first layer is formed of Ti adhesion layer on the material, the even layer of the second layer or more is formed of a TiN hard layer or a TiCN hard layer, and the odd layer of the third layer or more is formed of a Ti intermediate layer, and the hard layer and the intermediate layer. Alternating at least one time, and the alternating hard layer and the intermediate layer is finished with the hard layer last, the manufacturing method of the decorative gold hard film The method of claim 1, The Ti adhesion layer is 0.1-0.3μ thick, the TiN or TiCN hard layer is 0.1-0.3μ thick, the Ti thickening layer is 0.03-0.1μ thick manufacturing of decorative gold hard coating Way The method according to claim 1 or 2, A method of producing a decorative gold hard coating, characterized in that gold plating is carried out on the final crystalline layer after the end of the hard layer and the intermediate layer is finished.