TW201309820A - Method for making a housing and housing made by same - Google Patents

Abstract

A method for making a housing with black color is provided, which includes the following steps: providing a substrate; forming a colored layer on the surface of the substrate, the colored layer is a CrxCy layer, wherein the ratio of x to y is between 1: 6 and 1: 5; the colored layer is made by magnetron sputtering, using targets including chromium and carbide chromium, and using carbon source gas as reaction gas. In the CIE LAB color system, L * coordinate of the colored layer locates between 27 and 30, a* coordinate of the colored layer locates between -0.1 and 0.1, and b* coordinate of the colored layer locates between -0.1 and 0.1. A housing made by the above-mentioned method is also provided.

Description

Method for preparing housing and housing made by the method

The present invention relates to a method of making a housing and a housing made by the method.

At present, the most commonly used methods for preparing black coatings are electrochemical methods, such as anodized black film, black nickel plating, black chromium plating, etc., but the pollution of such methods is not environmentally friendly.

PVD coating technology is a more environmentally friendly coating process. However, the black film layer formed on the surface of the shell by PVD coating technology is prone to heterochromatic, blackish blue and black with red, which seriously affects the aesthetics of the black film; and the black film layer prepared by PVD is often The depth of black is not enough. The L* value of the chromaticity area of the film in the CIE Lab color system usually only reaches about 35. It is very difficult to continue to reduce the L* value.

In view of the above, the present invention provides a method of manufacturing a casing of a black PVD coating that effectively solves the above problems.

Further, the present invention provides a casing obtained by the above method.

A method of preparing a casing, comprising the steps of:

Providing a substrate;

Forming a color layer on the surface of the substrate, the color layer being a chromium-carbon layer having a chemical formula of Cr _x C _y , wherein the value of x:y is between 1:6 and 1:5; The magnetron sputtering method is used to form a composite target, and a carbon source reaction gas is introduced. The composite target contains metal chromium and chromium carbide, wherein the metal chromium has a mass percentage of 50-90% and a chromium carbide mass percentage. The content is 10~50%; the chromaticity region of the color layer is between 27 and 30 in the C* Lab color system, the a* coordinate is between -0.1 and 0.1, and the b* coordinate is between -0.1 to 0.1.

A housing comprising a substrate and a color layer formed on a surface of the substrate, the color layer being a chromium-carbon layer having a chemical formula of Cr _x C _y , wherein the value of x:y is between 1:6 and 1:5 The color layer presents a chromaticity region between the C* Lab color system with an L* coordinate between 27 and 30, an a* coordinate between -0.1 and 0.1, and a b* coordinate between -0.1 and 0.1. .

The invention uses a target containing metal chromium and chromium carbide in the preparation process of the color layer, and introduces a carbon source reaction gas, so that the chromaticity region of the obtained color layer is low in the L* of the CIE Lab color system. At 30. The casing exhibits an attractive black appearance with a balanced color and no black or blue in red; in addition, the color layer also has good abrasion resistance and can maintain its good black appearance for a long time while still The base body can be effectively prevented from being worn, and the service life of the housing is correspondingly extended.

The present invention provides a target 23 (shown in Figure 2) for producing a black film layer. The target 23 contains metal chromium (Cr) and chromium carbide (CrC), wherein the metal chromium has a mass percentage of 50 to 90%, and the chromium carbide has a mass percentage of 10 to 50%.

The method for preparing the target 23 of the present invention comprises the following steps:

(1) The ultrafine and high-purity powders of chromium and chromium carbide are placed in a ball mill and mixed uniformly, wherein the metal chromium has a mass percentage of 50-90%, and the chromium carbide has a mass percentage of 10-50% by weight. The time is 1~24 hours.

(2) The mixed powder material is pre-compressed by cold isostatic pressing to form a blank body, the pre-compression pressure is 100-300 MPa, and the dwell time is 1~10 min.

(3) The above-mentioned cold isostatically pressed green body is placed in a sintering furnace for hot pressing sintering, and the temperature is raised from room temperature, and the heating rate is 90 to 100 ° C / min, when the temperature is raised to 800 to 900 ° C. The pressure is 20~40MPa, and when the temperature rises to 1000~1500°C, the pressure is adjusted to 50~70MPa and the pressure is kept for 3~10min. After cooling, the block target was taken out.

It can be understood that the preparation method of the target 23 is not limited to the above method, and may be prepared by other methods.

The preparation method of the casing 10 (shown in FIG. 1) of the present invention comprises the following steps:

A substrate 11 is provided, which is made of metal, glass, ceramic or plastic.

The substrate 11 is subjected to a pretreatment which comprises the steps of conventional degreasing, wax removal, pickling, neutralization, spraying, etc. of the substrate 11.

A color layer 13 is formed on the surface of the substrate 11 by magnetron sputtering.

Referring to FIG. 2, a vacuum coater 20 is provided. The vacuum coater 20 includes a coating chamber 21 and a vacuum pump 30 connected to the coating chamber 21 for vacuuming the coating chamber 21. A rotating frame (not shown) and two targets 23 are provided in the coating chamber 21. The turret drives the base body 11 to run along a circular trajectory 25, and the base body 11 also rotates as it travels along the trajectory 25.

The specific operation method for forming the color layer 13 may be: fixing the base 11 to the turret of the vacuum coating machine 20, setting the revolution speed of the turret to 1 to 3 rpm (revolutions per minute), and vacuuming the present portion of the coating chamber 21 The bottom vacuum is 8×10 ⁻³ Pa. If the substrate 11 is plastic, the coating chamber 21 does not need to be heated (or kept at room temperature), and if the substrate 11 is metal, glass or ceramic, the coating chamber 21 is heated. The temperature of the coating chamber 21 is set to 50 to 200 ° C. The target 23 is used to set the power of the target 23 to 8 to 12 kW, and the bias voltage applied to the substrate 11 is set to be -50 to -200 V, and the duty ratio of the bias is 30. ~70%; the reaction gas acetylene is introduced, the flow rate of acetylene is 80-120 sccm, the working gas argon gas is introduced, and the flow rate of argon gas is 300-500 sccm, and the color layer 13 is deposited. The time for depositing the color layer 13 is 15 to 60 minutes. The color layer 13 is a chromium-carbon layer having a chemical formula of Cr _x C _y , wherein the value of x:y is between 1:6 and 1:5. The color layer 13 has a thickness of 1 to 3 μm. It can be understood that during the coating process, the reaction gas can also be other carbon source reaction gases such as methane.

The color layer 13 has a L* coordinate between 27 and 30 in the CIE Lab color system, an a* coordinate between -0.1 and 0.1, and a b* coordinate between -0.1 and 0.1.

It can be understood that the housing 10 of the present invention can also provide a transition layer between the base 11 and the color layer 13 to increase the film-based bonding force.

Referring to FIG. 1 again, the housing 10 obtained by the above preparation method includes a base 11 and a color layer 13 formed on the surface of the base 11. The color layer 13 is a chromium-carbon layer having a chemical formula of Cr _x C _y , wherein The value of x:y is between 1:6 and 1:5.

The base 11 is made of metal, glass, ceramic or plastic.

The color layer 13 is visually black in color, and the L* coordinate of the CIE Lab color system is between 27 and 30, the a* coordinate is between -0.1 and 0.1, and the b* coordinate is between -0.1 and 0.1. between. The color layer 13 has a thickness of 1 to 3 μm.

The invention will now be specifically described by way of examples.

Example 1

A base 11 is provided, which is made of stainless steel.

The pretreated substrate 11 is placed in a coating chamber 21 of a vacuum coater 20, which is an intermediate frequency magnetron sputtering coater.

The vacuum pump 30 is turned on to evacuate the coating chamber 21 and set the background vacuum degree to 8×10 ⁻³ Pa, the turntable is turned on and the rotation speed is set to 3 rpm, the coating chamber 21 is turned on and the temperature in the coating chamber 21 is set to 80. °C.

The content of metal chromium in the target 23 used was 50% by weight, and the remainder was chromium carbide.

After the vacuum degree of the coating chamber 21 is drawn to the above-mentioned set value, the target 23 is turned on, and the power of the target 23 is set to 8 kW, the bias voltage of the substrate 11 is -80 V, the duty ratio is 50%, and the working gas argon gas is introduced. And the reaction gas acetylene, the flow rate of argon gas was 300 sccm, the flow rate of acetylene was 105 sccm, the color layer 13 was deposited, and the deposition time was 40 min.

The color region 13 produced by the present embodiment exhibits a chromaticity region of 28.99 for the CIE Lab color system, an a* coordinate of -0.04, and a b* coordinate of -0.6.

Example 2

A substrate 11 is provided, the material of which is glass.

The vacuum coater 20 used in the present embodiment is the same as that in the first embodiment.

The vacuum pump 30 is turned on to evacuate the coating chamber 21 and set the background vacuum degree to 8×10 ⁻³ Pa, the turntable is turned on and the rotation speed is set to 3 rpm, the coating chamber 21 is turned on and the temperature in the coating chamber 21 is set to 80. °C.

The content of metal chromium in the target 23 used was 50% by weight, and the remainder was chromium carbide.

After the vacuum degree of the coating chamber 21 is drawn to the above-mentioned set value, the target 23 is turned on, and the power of the target 23 is set to 10 kW, the bias voltage of the substrate 11 is -100 V, the duty ratio is 50%, and the working gas argon gas is introduced. And the reaction gas acetylene, the flow rate of argon gas was 300 sccm, the flow rate of acetylene was 120 sccm, and the color layer 13 was deposited for a deposition time of 60 min.

The color region 13 produced by the present embodiment exhibits a chromaticity region of 29.54 for the CIE Lab color system, an a* coordinate of -0.47, and a b* coordinate of 0.05.

The housing 10 of the present invention may be a housing of an electronic device such as a notebook computer or a personal digital assistant, or a housing of other decorative products.

In the preparation process of the color layer 13, the present invention uses a target 23 containing metal chromium and chromium carbide, and passes a carbon source reaction gas, so that the chromaticity region of the obtained color layer 13 is in the CIE Lab color system. L* is below 30. The housing 10 exhibits an attractive black appearance with a balanced color and no black or blue in red; in addition, the color layer 13 also has good anti-wear properties and can maintain its good black appearance for a long time. At the same time, the base body 11 can be effectively prevented from being worn, and the service life of the housing 10 is correspondingly extended.

10. . . case

11. . . Matrix

13. . . Color layer

20. . . Vacuum coating machine

twenty one. . . Coating chamber

twenty three. . . Target

25. . . Trajectory

30. . . Vacuum pump

1 is a cross-sectional view of a coated member according to a preferred embodiment of the present invention;

2 is a top plan view of a vacuum coater according to a preferred embodiment of the present invention.

10. . . case

11. . . Matrix

13. . . Color layer

Claims (10)

A method of preparing a casing, comprising the steps of:
Providing a substrate;
Forming a color layer on the surface of the substrate, the color layer being a chromium-carbon layer having a chemical formula of Cr _x C _y , wherein the value of x:y is between 1:6 and 1:5; The magnetron sputtering method is used to form a composite target, and a carbon source reaction gas is introduced. The composite target contains metal chromium and chromium carbide, wherein the metal chromium has a mass percentage of 50-90% and a chromium carbide mass percentage. The content is 10~50%; the chromaticity region of the color layer is between 27 and 30 in the C* Lab color system, the a* coordinate is between -0.1 and 0.1, and the b* coordinate is between -0.1 to 0.1. The method for preparing a casing according to claim 1, wherein the process parameter for forming the color layer is: the power of the composite target is 8 to 12 kW, and the bias voltage applied to the substrate is -50 to -200 V, accounting for The air ratio is 30~70%; the carbon source reaction gas is acetylene, the flow rate of acetylene is 80~120sccm, argon gas is used as working gas, the flow rate of argon gas is 300~500sccm, and the coating temperature is 50~200°C or room temperature; The time for depositing the color layer is 15 to 60 minutes. The method for preparing a casing according to claim 1, wherein the substrate is made of metal, glass, ceramic or plastic. The method for preparing a casing according to claim 1, wherein the color layer has a thickness of 1 to 3 μm. The method of producing a casing according to claim 1, wherein the color layer is black. The method for preparing a shell according to claim 1, wherein the composite target is prepared by placing a powder of chromium and chromium carbide in a ball mill and mixing uniformly, wherein the mass percentage of the metal chromium is 50~90%, the mass percentage of chromium carbide is 10~50wt%, and the ball milling time is 1~24 hours; the mixed powder raw material is pre-pressed by cold isostatic pressing to form it into a blank body. The pre-pressing pressure is 100~300MPa, and the holding time is 1~10min; the blank is placed in the sintering furnace for hot pressing sintering, and the temperature is raised from room temperature, the heating rate is 90~100°C/min, and the temperature rises to 800~ The body is pressed at 900 ° C, the pressure is 20 ~ 40MPa, when the temperature rises to 1000 ~ 1500 ° C, the pressure is adjusted to 50 ~ 70MPa, pressure for 3 ~ 10min. A casing comprising a base body and a color layer formed on the surface of the base body, wherein the color layer is a chromium-carbon layer having a chemical formula of Cr _x C _y , wherein the value of x:y is between 1:6 and 1 Between 5; the color layer presents a chromaticity region between the C* Lab color system with an L* coordinate between 27 and 30, an a* coordinate between -0.1 and 0.1, and a b* coordinate between -0.1 Between 0.1 and 0.1. The casing of claim 7, wherein the base material is made of metal, glass, ceramic or plastic. The casing of claim 7, wherein the color layer has a thickness of 1 to 3 μm. The casing of claim 7, wherein the color layer is black.