Patent Application
20110254413
This Non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 201010148606.1 filed in People's Republic of China on Apr. 16, 2010, the entire contents of which are hereby incorporated by reference.
1. Field of Invention
The invention relates to a casing and a manufacture method thereof and, more particularly, to a casing of an electronic device protecting film and a manufacture method thereof.
2. Related Art
With the development of the science and technology, various kinds of consumptive electronic products are more and more popular. Meanwhile, the consumers have higher requirements on the exterior appearance, the manufacture technology of a conventional plastic appearance cannot satisfy the consumers.
For example, in the conventional plastic injection molding, the surface of the product is processed after the injection molding. Consequently, it is difficult to achieve three-dimension (3D) multi-color printing, and when the different parts of the product have different colors, the product cannot be integrally formed. Different parts can only be assembled after they are injection molded individually, which consumes more cost and time.
As a result, the advanced plastic surface manufacture technology is gradually used in the manufacture industry to meet domestic and international environmental standards instead. Among that, the free-spray in-mold decoration (IMD) technology is the most popular. IMD technology has many advantages makes IMD technology more applicable. The advantages are like environmental protection, scratch resisting, low cost, high tension, high efficiency, 3D molding, and special color effect which the conventional plastic injection technology does not have. For example, the IMD technology is adapted to certain high value—added plastic products, such as the electronic products and the automobile parts, especially for casings of the mobile phone, MP3 player and other electronic devices or the ornaments inside or outside a car.
In different IMD technologies, the in-mold film (IMF) injection molding is an extremely advanced one.
Then, as shown in
Since the plastic P is injected to the mold 2 through the injection inlet 20 of the mold 2, the patterns on the decoration layer 3 often been washed out in a position corresponding to the injection inlet 20, as shown in
Furthermore, when the mold 2 is removed in advance during the plastic injection molding, a shadow trace might be formed on the end product in a position K (as shown in
The invention provides a method for manufacturing a casing of an electronic device.
In an embodiment of the invention, a method for manufacturing a casing of an electronic device is provided. In the embodiment, the method for manufacturing the casing of the electronic device includes the following steps: providing a thin film with a protecting film in a mold; injecting plastic to the mold from an injection inlet of the mold to form the casing. The position of the protecting film corresponds to that of the injection inlet, where the protecting film and the plastic are integrated.
In an embodiment, the protecting film includes a base film and an adhesive, and the adhesive is between the thin film and the base film. The component of the base film includes polyimide, and the component of the adhesive includes acrylic ester copolymer, rosin ester resin and Polyethylene (PE). The ratios of the polyimide, the acrylic ester copolymer, the rosin ester resin and the PE are 40% to 60%, 15% to 35%, 5% to 25% and 5% to 15%, respectively, and in an embodiment, the ratios are 50%, 25%, 15% and 9%, which is, however, not limited herein.
Compared with the conventional technology, the method for manufacturing the casing of the electronic device in an embodiment is not only to avoid a washing out phenomenon effectively by using a protecting film, but also to integrate the protecting film on the thin film and the thermoplastic polymer gradually in the process of injecting the thermoplastic polymer to the mold. According to an embodiment, forming a decoration layer by printing many times as the conventional technology is not a necessary process. Thus, the time for printing and drying in the plastic injection molding process and the human resource cost are saved greatly, and the market competitiveness is improved. Moreover, the method for manufacturing the casing of the electronic device in an embodiment avoids leaving a shadow trace or an uneven place at the position of the plastic injection mold corresponding to the injection inlet, and improves the beauty of the product outlook.
These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings.
In an embodiment, the method for manufacturing the casing of the electronic device is an IMF injection molding method, which is not limited herein.
Generally, the protecting film is mainly used to protect the patterns being washed out during plastic injection, and thus the area of the attached protecting film is defined based on the injection inlet area of the mold. For example, the injection inlet area of the mold corresponding to the protecting film is cylindrical, when the diameter of the cylindrical injection inlet is large, the sticking area of the protecting film should be large correspondingly to prevent the patterns being washed out. Conversely, when the diameter of the cylindrical injection inlet area is small, the area of the protecting film can be small to save material cost.
Practically, the protecting film includes a base film and an adhesive, and the adhesive is disposed between the thin film and the base film. In one embodiment, the component of the base film includes polyimide, the component of the adhesive includes acrylic ester copolymer, rosin ester resin and Polyethylene (PE), is not, however, limited herein. Moreover, in one embodiment, the ratios of the polyimide, the acrylic ester copolymer, the rosin ester resin and the PE are ranged from 40% to 60%, 15% to 35%, 5% to 25%, and 5% to 15%, respectively. In one embodiment, the ratios of the polyimide, the acrylic ester copolymer, the rosin ester resin and the PE may be 50%, 25%, 15% and 9%, which is not, however, limited herein.
After the thin film with the protecting film is disposed in the mold, step S12 is executed to inject the plastic from the injection inlet to the mold to form the casing, wherein the position of the attached protecting film corresponds to the position of the injection inlet to avoid the pattern being washed-out. In practical application, the plastic is a thermoplastic polymer material; however, the type of plastic is not limited herein.
In the process of injecting the plastic to the mold, the protecting film attached to the thin film are combined with the plastic gradually. After the casing is formed, the protecting film and the plastic are integrated (Step S14). However, in practical application, the protecting film may not be completely combined with the plastic, a part of the protecting film may remain uncombined without any impact on the casing. Practically, the ratios of the component of the protecting film can be adjusted according to the requirement to integrate the protecting film and the plastic completely. Furthermore, before the plastic is injected to the mold, the thin film may be three-dimensionally shaped according to the mold or the casing product in advance, which is not limited herein.
In practical application, the material of the decoration layer may be ink, Polyethylene (PE), Polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polymethylmethacrylate (PMMA), Polyvinylchloride (PVC), polyurethane (PU) and polyamide (PA), which is not limited herein.
As shown in
Then, performing Step S22 and the following Step S24, the thin film with the protecting film is disposed in the mold, and then the plastic injected is injected from an injection inlet into the mold to form the casing. As shown in
In the process of injecting the plastic P to the mold 5, the protecting film 7 on the thin film 4 is combined with the plastic P gradually. When the casing is formed, as shown in
The number and the position of the injection inlets of the mold in the mentioned embodiment are not limited, and can be determined according to the practical requirement. In an embodiment, the mold includes two injection inlets.
First, as shown in
In the process of injecting the plastic P1 and P2 to the mold 11, the protecting films 13 and 14 of the thin film 10 and the plastic P1 and P2 are combined gradually. After the casing is formed, as shown in
In practical application, the protecting films 13 and 14 and the plastic P1 and P2 may not be combined completely, with a part remaining, but the remained protecting film has no negative influence on the plastic P1 and P2 or the final in-mold injection product 15. Practically, the ratios of the component of the protecting films 13 and 14 can be regulated according to the requirement, so as to combine the protecting films 13 and 14 and the plastic P1 and P2 completely. Moreover, before the plastic P1 and P2 are injected to the mold 11, the thin film 10 may be three-dimensionally molded in advance, which is not limited herein.
Compared with the conventional technology, with the method for manufacturing the casing of the electronic device, the washing out phenomenon is avoided effectively via the protecting film. Furthermore, the protecting film attached to the thin film is gradually combined with the thermoplastic polymer in the process of injecting the thermoplastic polymer to the mold. Thus, it does not need to form the decoration layer by several-times printing as the conventional technology, as a result, time and labor for printing and drying the whole plastic injection molding are saved greatly, which improves the market competitiveness.
The casing of the electronic device using the manufacture method in the embodiments includes a casing body which may be made of plastic, polyimide, acrylic ester copolymer, rosin ester resin and PE. The ratios of the polyimide, the acrylic ester copolymer, the rosin ester resin and the PE are ranged from 40% to 60%, from 15% to 35%, from 5% to 25%, and from 5% to 15%, respectively, and the ratios may be 50%, 25%, 15% and 9%, respectively. According to the method manufacturing the casing of the electronic device, a shadow trace or an uneven place on the plastic injection mold corresponding to the injection inlet is avoided, and thus the appearance is more beautiful.
Although the present invention has been described in considerable detail with reference to certain preferred embodiments thereof, the disclosure is not for limiting the scope of the invention. Persons having ordinary skill in the art may make various modifications and changes without departing from the scope. Therefore, the scope of the appended claims should not be limited to the description of the preferred embodiments described above.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201010148606.1 | Apr 2010 | CN | national |
