JPS62116762A - Production of external parts - Google Patents

Abstract

PURPOSE:To obtain external parts formed with a film which has high wear resistance and corrosion resistance, is clean and has diversified color tones and the gloss like the gloss of precious stones by executing ion plating of Ti in a specific gaseous mixture atmosphere and with a relatively low voltage. CONSTITUTION:A base body 3 for a timepiece case, etc., having conductivity is held by a base body 3 holder 4 to face a vapor source 5 of metallic Ti. The atmosphere of 5X10<-4>-1X10<-2>Torr pressure is formed by the gaseous mixture composed of N2 and Ar contg. 0.1-5.0vol% O2 and 0.1-3.0% CO2. The above-mentioned vapor source 5 is heated therein by an electron gun 8, etc., to evaporate Ti. 1-450V voltage is then impressed between the above- mentioned vapor source 5 which is an anode and the base body 3 which is a cathode by a DC power source 9. The external parts having the diversified color tones are thus obtd. by such method without inducing sputtering or abnormal discharge on the product surface.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application 9f) This invention is a method for manufacturing exterior parts such as personal watches that have various black tones, and in particular, uses a titanium ion plating method to produce black color. Relates to improvements in methods for forming coatings.

(Prior art and its problems) Conventionally, titanium ion plating υ was used.
It is well known that a black film is formed on a metal surface and used for exterior parts such as watches. For example, in Japanese Patent Publication No. 58-53716, a black film is formed by applying a high voltage of 0.5 to 4 KV in a nitrogen gas atmosphere. A method is shown for forming the .

Although the above method produces glossy blackness of 1, since ion plating is performed under high voltage, (1) even after honing treatment, it is difficult to remove with normal washing, and the surface of the material is Abrasive grains such as alumina and glass beads that remain on the surface tend to cause abnormal discharge and sputtering (2)
There were problems such as the reaction was unstable and a color tone that met customer needs could not be obtained.

(Means for Solving the Problems) The present invention is intended to solve the problems mentioned above, and its first purpose is to provide various black tones suitable for the market, and to have a gloss like a precious stone. An object of the present invention is to provide a method for manufacturing an exterior component having the following characteristics.

The method for manufacturing exterior parts according to this invention is 5×10-4
Titanium is emitted in a mixed gas atmosphere of arbon, nitrogen and trace amounts of unavoidable components at a pressure of 0-2 Torr, and a direct current of 1 to 450 V is applied between the titanium evaporation source and the surface of the cathode substrate. The method consists of applying a voltage and performing ion plating at a current of 4ti of 5A or less to form a black film, thereby achieving the above object.

Next, an outline of the present invention will be explained based on the drawings. Metal titanium is placed on the evaporation source 2 provided at the bottom of the vacuum container l,
On the other hand, a workpiece 4 is attached to the body 3 which also serves as the cathode of the second part. ! After evacuating the inside of the empty container 1, inject a mixed gas of argon and nitrogen to increase the gas pressure inside the container to 5X10.
~I X l 0-2Torr, preferably 8X10
−'~5X10'Torr, then 1~450V between the surface of the titanium evaporation source 2 and the cathode substrate 3.
While applying a DC voltage, preferably 10 to 100 volts, the substrate current is kept below 5 A, and the metallic titanium is evaporated by an electron beam generator.

When carrying out method V, it was observed that non-i+ (avoidable components such as C and 02 contained in the walls of the vacuum container and in the mixed residue were occluded by the titanium due to the getter action, which affected the black tone. This means that while the work continues, the initial black tone gradually changes to gray-black, and when nitrogen is newly introduced from outside the system, it returns to the original color, and various color tones can be obtained by adjusting the nitrogen concentration. Therefore, in the present invention, the presence of the above-mentioned unavoidable components and the adjustment of the nitrogen concentration are important.

In the present invention, the gas pressure in the vacuum container is set to 5 x 10' ~
The reason for keeping the plate below 5A is 5 X I 0-4 Tarr.
If it exceeds 10' Tor
This is because if it deviates from r, glow discharge will occur and the coating will become rough, and if it is higher than 5A, the reaction of TiN will take precedence and the coating will become yellow, making it impossible to obtain a black coating.

By this method, a titanium film is formed on the surface of the object to be treated, which has a bright black tone and has a luster similar to that of blue stone.

Hereinafter, an explanation will be given according to an example carried out using this apparatus.

(Example 1) An eyeglass frame was attached to the base as the object to be processed, and argon gas was first injected into the vacuum container and 5XIO-3↑or
The pressure was maintained at r. 50.100 each in this state
．． Nitrogen gaff with a flow rate of 150cc/min.
The cathode applied voltage is ilo, 50. Zoo, 20
When titanium was evaporated with an electron beam of 10 KVo and 3 A instead of 0.400 V, the color tone and gloss IL of the glasses frame were investigated, and the results shown in Table 1 were obtained.

Table 1 t (Note) Faded color refers to a dark color with a mixture of red, blue, and green.

(Example 2) The pressure of argon gas in the vacuum volume χ (
orr and nitrogen gas (7) jQ jharuka to 50.
Example 1 except that the settings were 100, 150, and 200 cc/min.
The test was carried out using the same softness as 1, and the color tone and gloss were examined. Using eyeglass frames as objects, the holding pressure of argon gas in the vacuum container was 5XIO'Torr, the amount of nitrogen gas injected was 150cc/min, and the voltage applied to the cathode was 100%.
V, ゛We observed changes in the color tone of the eyeglass frames while continuing ion plating under the conditions of electron beam 1 OK V 0.3 A, and as shown in Table 3, as the number of ion plating increases, the color changes to black even under the same conditions. It was observed that the color changed from to gray. This is considered to be due to a decrease in the inevitable components present in the system.

Table 3 On the other hand, when the concentration of nitrogen gas was adjusted and repeated at predetermined intervals, the desired color tone could be maintained. therefore,
According to this invention, it is understood that various color tones can be maintained constant by adjusting the C degree of nitrogen gas.

(Effects of IJ+) As explained above, according to the present invention, (1) High pressure is not used during ion plating, so there is no sputtering or abnormal discharge on the surface of the product, and the surface is clean! Exterior parts with a P13 color tone and a luster similar to precious stones can be obtained. (2) The resulting coating has high wear resistance and corrosion resistance, and can withstand long-term use. (3) Even in the presence of unavoidable components, there are many effects such as the ability to smoothly proceed with the reaction without affecting the quality of the product.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an outline of an ion plating apparatus used for carrying out the present invention. (Explanation of main symbols in the drawings) i--Vacuum vessel, 2-Evaporation source, 3-Cathode, 4-Processed object, 5-Gas inlet, 6-
··exhaust port. 7... Electron beam generator, Patent applicant Citizen Watch Co., Ltd. Procedural amendment written on December 2, 1985 j''. Commissioner of the Patent Office Kuro 1) Mr. Akio 1, Indication of the case 1985 Patent Application No. 256108 No. 2, Name of the invention Method for manufacturing exterior parts 3, Relationship with the person making the amendment Patent applicant name Citizen Watch Co., Ltd. 4, Agent 5, Full text of the specification to be amended and drawings 6, Contents of the amendment 1 ) The entire text of the specification is amended as shown in the attached sheet. 2) Figure 1 is amended as shown in the attached sheet. Amended Description (Patent Application No. 1988-256108)
1. Name of the invention Method for manufacturing exterior parts 2. Claims a) 0.1-5.0% by volume of oxygen and 0.1-3.0% by volume
A mixed gas of nitrogen and argon containing % carbon dioxide by volume at a pressure of 5 x 10-' to I x 10-''To
b) heating the titanium metal evaporation source to vaporize the metal; C) the substrate as a cathode. A method for manufacturing an exterior component, characterized in that a voltage of 1 to 450 V is applied between the metal titanium evaporation source serving as an anode and the metal titanium evaporation source. 3. Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for manufacturing various black-toned exterior parts such as watch cases and chains, eyeglass frames and other similar products, and particularly relates to a method for manufacturing exterior parts such as watch cases and chains, eyeglass frames, and other similar products, particularly in the case of titanium. It relates to a method of imparting various black tones to the surface of exterior parts using the ion plating method. (Prior Art) It is well known that a beautiful blackish-colored surface layer can be formed on the surface of exterior parts such as watch cases, watch chains, eyeglass frames, and other similar products by the so-called ion plating method. This is the technology of For example, the special public service in 1988
53716, in a reduced pressure nitrogen gas atmosphere, between the article to be treated and the heated metal titanium.
An ion plating method is disclosed in which a high voltage of 0 V is applied, thereby depositing a dark layer consisting primarily of titanium nitride on the surface of the article. Furthermore, Japanese Patent Application Publication No. 208472 discloses an ion plating method carried out in an atmosphere of a mixture of argon, nitrogen and hydrocarbons. (Problems to be Solved by the Invention) Although the above-mentioned conventional methods are effective in forming a glossy blackish surface layer on the surface of an article, they have several drawbacks. For example, in the former method, the surface of the article is pre-polished prior to ion plating, but since the abrasives such as glass beads and alumina used at that time cannot be completely removed, the evaporation source of the substrate and titanium metal is When high voltage is applied between the two, abnormal discharge or sputtering tends to occur. Furthermore, the titanium nitride deposition process is unstable and difficult to control, and the surface layer often exhibits a yellowish black color, rather than the variety of black tones desired by users. In addition, in the latter method, the vapor-deposited surface layer contains a carbon component and is highly strained, so that one surface layer is likely to peel off. Furthermore, it is difficult to accurately control the ratio of the three components of the gas atmosphere, and there is a drawback that the color reproducibility of the deposited surface layer is poor. (Means for Solving the Problems) An object of the present invention is to produce a method for producing an exterior part having a blackish surface layer with a beautiful tone and a shine similar to that of a precious stone, which meets the user's requirements by using an ion plating method. The method of the present invention consists of the following steps. a) 0.1-5.0% by volume of oxygen and 0.1-3.0%
A mixed gas of nitrogen and argon containing % carbon dioxide by volume at a pressure of 5 x 10-' to I x 10-''T
b) heating the titanium metal evaporation source to vaporize the metal; C) the substrate as a cathode; A voltage of 1 to 450 Å is applied between the evaporation source of titanium metal and the anode. DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus for carrying out the method of the present invention will now be explained in more detail with reference to the accompanying drawings, which conceptually show the apparatus. As shown in FIG. 1, a small piece of titanium metal, which is an evaporation source, is placed on a table 2 in a reaction vessel 1 that can be evacuated. 3. A substrate with a conductive surface on the other hand. For example, a watch case whose surface has been cleaned by preliminary treatment such as honing or chemical treatment is held by the base holder 4 at the evaporation source 5 of metallic titanium.
Hold it opposite. There are no particular restrictions on the shape of the base 3 other than that the surface is electrically conductive. Next, the inside of the reaction vessel 1 is evacuated by evacuation through the exhaust port 6, and then a mixed gas of nitrogen and argon is introduced from the air supply lower and discharged from the exhaust port 6, and the supply and exhaust are controlled. Pressure inside 5
X 10-' to I X 10-"Torr preferably 8
Set to X to-' -5X 1O-3Torr. When introducing a mixed gas of nitrogen and argon into the reaction vessel, the ratio thereof is not particularly limited as long as the nitrogen content is 50% by volume or more. In the conventional ion plating method, the mixed gas of nitrogen and argon must contain as few impurities as oxygen and carbon dioxide, but in the method of the present invention, the atmosphere introduced into the reaction vessel 1 Gas is 0.1~
It is characterized by containing 5.0% by volume of oxygen and 0.1-3.0% by volume of carbon dioxide. After creating an atmosphere under such conditions, the evaporation source 5 for metallic titanium is heated by an appropriate method to vaporize titanium. In order to effectively vaporize metallic titanium, the temperature of the metallic titanium evaporation source 5 should be approximately 1600'C, that is, 1500 to 1700°C.
Keep at ℃. A convenient heating method for titanium metal is
For evaporation g5 of titanium metal. Irradiate an electron beam with an appropriate acceleration voltage from the electron gun 8,
There is a method of bombarding titanium metal. Then, the DC power supply 9 generates a voltage of 1 to 450V, preferably 10 to 450V.
A DC voltage of too V is applied between the metal titanium evaporation source 5, which is an anode, and the substrate 3, which is a cathode. The use of such relatively low voltages is also a feature of the present invention, since in the prior art it is common for voltages between the substrate and the evaporation source to be 500 volts or higher. The ionic current flowing between the substrate and the evaporation source is not particularly limited by the size of the substrate being treated, but it is Usually 0.1-5. OA preferably 0.5-2. It is appropriate to maintain it at OA. What should be noted here is that impurities such as oxygen and carbon dioxide contained in the gas introduced from the lower supply air have a low electron voltage, so the bombardment of the electron beam increases the ion current. , which has a strong influence on the color tone of the deposited surface layer. The presence of such impurities in the ambient gas has a significant effect on the color tone of the titanium nitride surface layer deposited on the surface of the substrate, in order to reliably and reproducibly form a beautiful black surface. Motsu. It is also a surprising discovery that the beautiful black surface layer, consisting mainly of titanium nitride, deposited on the substrate contains surprisingly large amounts of oxygen and carbon, in some cases more than 20% by weight. - By way of example, the surface layer deposited by the method of the invention is 35% titanium, 20% nitrogen and 25% oxygen by weight.
, 20% carbon. In contrast, a typical gold-colored titanium nitride layer deposited by conventional methods in an atmosphere containing only inevitable amounts of oxygen and carbon as impurities consists of 45% titanium, 45% nitrogen, 5% oxygen, and 5% carbon. . Furthermore, the above-mentioned limit on the pressure of the atmospheric gas within the reaction vessel 1 is important. This is because when the pressure is lower than the above-mentioned low limit, the voltage between the evaporation source 5 of metallic titanium and the substrate 3 is not sufficient to ensure the deposition of titanium nitride by ion plating, while the pressure is below the above-mentioned high limit. When the temperature is high, glow discharge occurs, and the surface of the titanium nitride deposited on the substrate 3 becomes rough. Furthermore, when the current between the metallic titanium evaporation source 5 and the substrate 3 is too large for the substrate being processed, the reaction to form TiN containing less oxygen and carbon takes priority;
The color of the surface layer deposited on the substrate 3 is yellowish and a variety of black colors cannot be obtained. Next, the method of the present invention will be explained in detail by giving examples. (Example 1) A frame of glasses with a metal titanium layer was used as the substrate to be processed, and it was attached to the substrate holder 4, and a mixed gas of nitrogen gas and argon containing various concentrations of oxygen and carbon dioxide shown in Table 1 was introduced into the reaction vessel 1. The pressure inside the reaction vessel was maintained at 5 x 10-3 Torr by controlling the exhaust and air supply. Next, metallic titanium is bombarded and heated with an electron beam at an accelerating voltage of 10 kV and a current of 0.3 A, and the temperature is raised to 1600° C. to vaporize titanium. Next, a voltage of 10.50.100.200.400V (7) is applied between the evaporation source of metallic titanium, which is the anode, and the substrate, which is the cathode.
When DC voltage was applied, 1.1O515 and 2
An ionic current of 0°30A flowed. This current was applied for 30 minutes to complete the surface treatment of the substrate. At this time, the color tone of the surface layer formed on the substrate surface was visually evaluated and is shown in Table 1. Table 1 "Faded gray" obtained when the voltage is 400V is red,
A dark color tone that is a mixture of blue and green. (Example 2) The pressure inside the reaction vessel 1 was 8 x 10-' Torr,
The treatment was carried out under the same conditions as in Example 1 except that the titanium metal was heated to 1500°C. The ion current flowing for each voltage of 10.50, 100.200, and 400V is 0.5.5.10.1, respectively.
It was 5.20A. The evaluation results at this time are shown in Table 2. Table 2 (Example 3) The substrate is a watch case, which is made of brass coated with 3 μl of nickel and then with 3 μs of palladium and nickel alloy. A mixed gas of nitrogen gas and argon containing oxygen and carbon dioxide at a concentration of 4% by volume and 5% by volume, respectively, was introduced into the reaction vessel, and the pressure inside the vessel was increased to 8% by volume.
A beam current of 0.3 A was applied at an accelerating voltage of 10 kV to heat and vaporize the titanium metal at 1500° C., and an ion current of 5 A was applied for 30 minutes at a voltage of 50 V. As a result, a beautiful glossy black layer with a thickness of 1 μm was obtained on the surface of the watch case. (Example 4) The base was a stainless steel watch chain, and a mixed gas of nitrogen gas and argon, in which the concentrations of oxygen and carbon dioxide were both 0.1% by volume, was charged into the reaction vessel at a pressure of 5 x 10-'Torr. The titanium metal was heated and vaporized to 1600° C. by supplying and exhausting air, and a beam current of 0° and 3 A was passed at an accelerating voltage of 10 kV, and an ion current of 5 A was passed for 30 minutes at a voltage of 1 OOv. As a result, a beautiful black-gray layer with a thickness of 0.8 μl was obtained on the surface of the watch chain. (Example 5) The concentrations of oxygen and carbon dioxide in nitrogen gas are both 2% by volume.
A watch case substrate was treated under the same conditions as Example 4, except that a beautiful black surface layer was obtained. (Effects of the Invention) As explained above, according to the present invention, (1) high voltage is not used during ion plating, so sputtering or abnormal discharge does not occur on the product surface, and clean and diverse color tones can be produced with precious stones. An exterior part with such gloss can be obtained. (2) The resulting coating has high wear resistance and corrosion resistance,
Can withstand long-term use. 4. Brief Description of the Drawings FIG. 1 is an explanatory diagram schematically showing an ion plating apparatus used in the method of the present invention. 1... Reaction container, 2... Table, 3...
・Base. 4...Substrate holder,...Vaporization source of metallic titanium. 6...Exhaust port, 7...Air supply port, 8...Electron gun, 9...DC power supply.

Claims (1)

[Claims] Titanium is evaporated in a mixed gas atmosphere of argon, nitrogen, and trace amounts of unavoidable components under a pressure of 1,5 x 10^-^4 to 1 x 10^-^2 Torr, and the titanium is evaporated between the titanium evaporation source and the cathode substrate surface. 1. A method for producing an exterior component, which comprises applying a DC voltage of 1 to 450 V to the surface of the wafer, and performing ion plating at a current value of 5 A or less to form a black-toned film.