TWI429365B - Housing for electronic device and method for making the same - Google Patents

Description

Electronic device housing and method of manufacturing same

The present invention relates to an electronic device housing and a method of manufacturing the same.

Most of the outer casings of electronic devices such as mobile phones are made of plastic or metal alone. The metal casing has good mechanical strength, but the metal casing has a shielding effect on electromagnetic waves. For electronic devices with radio frequency transmitting and receiving functions, such as mobile phones and wireless Internet access computers, the radio frequency requirements cannot be met. Although the plastic case can meet the RF requirements, it lacks the bright texture of the metal case.

In order to obtain a metallic texture on the surface of the plastic casing, a metal color vacuum coating process is usually performed. However, the coating layer is usually formed on the outer surface of the outer casing of the electronic device, so that the coating layer is easily worn or peeled off after being used for a period of time, thereby affecting the original appearance.

In view of the above, it is necessary to provide an electronic device housing having a metallic appearance and being less prone to wear.

In addition, it is also necessary to provide a method of manufacturing the above-described electronic device casing.

An electronic device casing comprising a plastic substrate and bonded to the surface of the plastic substrate a decorative film comprising a transparent plastic film, the decorative film further comprising a vacuum coating layer having a metal appearance formed on a surface of the plastic film, a varnish layer formed on the vacuum coating layer, formed on the a color layer on the varnish layer, a protective layer formed on the color layer, and a binder layer formed on the protective layer, the plastic substrate being bonded to a surface of the adhesive layer opposite to the protective layer to make the vacuum coating layer The varnish layer, the color layer, the protective layer and the adhesive layer are located between the plastic substrate and the plastic film.

A method for manufacturing an electronic device casing, comprising the steps of: providing a decorative film comprising a transparent plastic film, a vacuum coating layer having a metal appearance formed on a surface of the plastic film, and forming the vacuum coating layer a varnish layer thereon, a color layer formed on the varnish layer, a protective layer formed on the color layer, and a binder layer formed on the protective layer; the decorative film is formed and cut into a predetermined shape; The cut decorative film is placed in a mold, and the molten plastic is injected into the mold to form a plastic substrate, and the plastic substrate is bonded to the adhesive layer.

Compared with the prior art, the electronic device casing forms a vacuum coating layer having a metallic appearance on the inner surface of the plastic film, and simultaneously prints a color layer on the plastic film, so that the electronic device casing presents a bright metallic appearance, and The protection of the plastic film makes the vacuum coating layer less susceptible to wear. More importantly, a varnish layer is provided between the vacuum coating layer and the color layer, which can improve the bonding force between the vacuum coating layer and the color layer composed of the ink, and prevent the vacuum coating layer from being impacted, impacted by thermal shock, etc. during use. The effect is separated from the color layer. In addition, the protective layer is provided on the color layer to prevent The color layer is washed away by the molten plastic when the plastic substrate is injected.

100‧‧‧Electronic device housing

10‧‧‧Plastic matrix

20‧‧‧Decorative film

21‧‧‧Plastic film

23‧‧‧vacuum coating

25‧‧‧ varnish layer

26‧‧‧Color layer

27‧‧‧Protective layer

28‧‧‧Binder layer

1 is a cross-sectional view showing the outer casing of an electronic device according to a preferred embodiment of the present invention.

The electronic device housing 100 of the preferred embodiment of the present invention, as shown in FIG. 1, includes a plastic substrate 10 and a decorative film 20 bonded to the surface of the plastic substrate 10.

The decorative film 20 includes a plastic film 21, a vacuum coating layer 23, a transparent varnish layer 25, a color layer 26, a protective layer 27, and a binder layer 28.

The plastic film 21 is made of a transparent plastic. The vacuum coating layer 23 is formed on one surface of the plastic film 21. In order not to affect the radio frequency transmitting and receiving functions of the electronic device using the electronic device housing 100, the vacuum coating layer 23 is a non-conductive discontinuous coating layer having a metallic appearance effect and having light transparency. The material for forming the vacuum plating layer 23 may be a metal such as tin (Sn) or indium (In) or an alloy thereof, or a non-metal material such as cerium oxide or aluminum oxide having a metallic appearance. The vacuum plating layer 23 can be formed by sputtering, vapor deposition, or the like, and this embodiment is formed by sputtering.

The varnish layer 25 (also referred to as varnish) is formed on the surface of the vacuum coating layer 23. The varnish layer 25 is mainly composed of a resin and other auxiliaries, and does not contain a pigment substance.

A color layer 26 is formed on the varnish layer 25. The color layer 26 is formed of ink to provide an appearance color to the electronic device housing 100.

A protective layer 27 is formed on the color layer 26. The protective layer 27 may be formed of an ink for protecting the color layer 26.

A bonding layer 28 is formed on the protective layer 27 for reinforcing the decorative film 20 and the plastic substrate 10 The bond between the two. The adhesive layer 28 may be formed of an epoxy resin, a urethane resin, or an acrylate resin-based adhesive.

The plastic substrate 10 is combined with the adhesive layer 28 of the decorative film 20 by injection molding, so that the vacuum coating layer 23, the varnish layer 25, the color layer 26, the protective layer 27 and the adhesive layer 28 are located on the plastic substrate 10 and the plastic film 21. between.

The electronic device casing 100 forms a vacuum coating layer 23 having a metallic appearance on the inner surface of the transparent plastic film 21, and a color layer 26 is printed on the plastic film 21, so that the electronic device casing 100 exhibits a beautiful metallic appearance, and The protection of the plastic film 21 makes the vacuum coating layer 23 less susceptible to wear. More importantly, a transparent varnish layer 25 is disposed between the vacuum coating layer 23 and the color layer 26 to improve the bonding force between the vacuum coating layer 23 and the color layer 26 composed of the ink, thereby effectively preventing the vacuum coating layer 23 from being During use, the color layer 26 is peeled off due to impact, thermal shock, and the like. Further, the protective layer 27 is provided on the color layer 26 to prevent the color layer 26 from being washed away by the molten plastic when the plastic substrate 10 is injected.

The method of manufacturing the electronic device housing 100 described above includes the following steps: First, a decorative film 20 is provided. The decorative film 20 has the structure as described above, and includes the plastic film 21, the vacuum coating layer 23, the transparent varnish layer 25, the color layer 26, the protective layer 27, and the adhesive layer 28. The vacuum coating layer 23 can be formed by vacuum sputtering or vacuum evaporation. The varnish layer 25, the color layer 26, and the protective layer 27 can be formed by printing or the like.

The decorative film 20 is molded and cut into a predetermined shape.

Finally, a molding die is provided, and the cut decorative film 20 is placed in the mold. The molten plastic is injected into the mold to form the plastic substrate 10. The plastic substrate 10 is bonded to the adhesive layer 28 of the decorative film 20 such that the vacuum coating layer 23, the varnish layer 25, the color layer 26, the protective layer 27 and the adhesive layer 28 are located between the plastic substrate 10 and the plastic film 21.

The electronic device housing 100 prepared by the above method is subjected to a thermal shock test, a damp heat test, and an ultraviolet irradiation test.

The hot and cold test conditions and results are: 2 hours at 85 ° C, 2 hours at -40 ° C, 3 minutes for temperature change, 5 cycles, 20 hours for testing, between plastic film 21 and plastic substrate 10 There was no separation of the film layer.

The damp heat test conditions and results are: humidity of 97%~99%, 9 hours at 25°C, 9 hours at 65°C, temperature change time of 3 hours, 18 cycles, a total of 18 days, plastic film 21 and There is no separation of the layers between the plastic substrates 10.

The conditions and structure of the ultraviolet irradiation test were as follows: ultraviolet light for 4 hours (irradiance of 0.36 W/m2/nm, ultraviolet light wavelength of 340 nm), temperature of 60 ° C; no light for 4 hours, temperature of 50 ° C; 12 cycles were measured. After 4 days of testing, no separation occurred between the layers of the plastic film 21 and the plastic substrate 10.

100‧‧‧Electronic device housing

10‧‧‧Plastic matrix

20‧‧‧Decorative film

21‧‧‧Plastic film

23‧‧‧vacuum coating

25‧‧‧ varnish layer

26‧‧‧Color layer

27‧‧‧Protective layer

28‧‧‧Binder layer

Claims (10)

An electronic device casing comprising a plastic substrate and a decorative film bonded to the surface of the plastic substrate, the decorative film comprising a transparent plastic film, wherein the decorative film further comprises a surface formed on the plastic film a vacuum coating layer of a metal appearance, a varnish layer formed on the vacuum coating layer, a color layer formed on the varnish layer, a protective layer formed on the color layer, and a binder layer formed on the protective layer, The plastic substrate is bonded to the opposite surface of the adhesive layer from the protective layer such that the vacuum coating layer, the varnish layer, the color layer, the protective layer and the adhesive layer are located between the plastic substrate and the plastic film. The electronic device casing of claim 1, wherein the vacuum coating layer is a discontinuous coating layer. The electronic device casing according to claim 1, wherein the vacuum coating layer is made of a metal or a non-metallic material having a metallic appearance. The electronic device casing of claim 1, wherein the color layer is composed of ink. The electronic device casing of claim 4, wherein the protective layer is composed of ink. A method for manufacturing an electronic device casing, comprising the steps of: providing a decorative film comprising a transparent plastic film, a vacuum coating layer having a metal appearance formed on a surface of the plastic film, and forming the vacuum coating layer a varnish layer thereon, a color layer formed on the varnish layer, a protective layer formed on the color layer, and a binder layer formed on the protective layer; The decorative film is shaped and cut into a predetermined shape; the cut decorative film is placed in a mold, and the molten plastic is injected into the mold to form a plastic substrate, and the plastic substrate is bonded to the adhesive layer. The method of manufacturing an electronic device casing according to claim 6, wherein the material for forming the vacuum coating layer is a metal or a non-metallic material having a metallic appearance. The method of manufacturing an electronic device casing according to claim 7, wherein the vacuum coating layer is formed by sputtering or evaporation. The method of manufacturing an electronic device casing according to claim 6, wherein the color layer and the protective layer are composed of ink. The method of manufacturing an electronic device casing according to claim 9, wherein the varnish layer, the color layer and the protective layer are formed by printing.