Abstract:
The present invention discloses a cover including a base, a patterned layer, a protective layer and a bottom layer. The base has a first surface, and a second surface on the opposite side of the first surface. The patterned layer is formed on the first surface of the base. The protective layer and the bottom layer are integrally formed on the second surface of the base and on the patterned layer respectively by injection molding. The present invention also provides a method for manufacturing a cover. The present cover can tend give a various and vivid appearances whilst also having good performance.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is related to a co-pending U.S. Patent Applications, entitled “COVER AND METHOD FOR MANUFACTURING THE SAME”, by Jeng-Chi Peng et al. with Attorney Docket No. 14963-56249. Such application has the same assignee as the present application and has been concurrently filed herewith. The disclosure of the above identified application is incorporated herein by reference. 
     
    
     1. TECHNICAL FIELD 
       [0002]    The present invention relates generally to covers, and more particularly to a cover with multiple layers having an improved performance and appearance. The present invention also relates to a method for manufacturing the cover. 
       2. BACKGROUND 
       [0003]    Covers are widely used for the purpose of protecting gadgets, such as notebook computers, personal digital assistants, mobile phones, car instruments, and so on. To make these gadgets more physical appealing, the covers are decorated to have good appearances. Covers having exhibiting different appearances are prepared by one of coating, double injection molding, and in-mold labeling methods. 
         [0004]    Typically, a cover is manufactured by a method of coating a resin layer on a surface of a colored sheet or film. However, the resin layer of such cover is prone to be broken off from the colored sheet or film, thus the appearance of cover is influenced. The method of double injection molding is carried out by injecting two kinds of materials separately into a mold, thereby forming a cover having patterns thereon. However, the patterns of such cover are simple. The in-mold labeling method typically includes the following steps of: adhering a film having patterns on an inner wall of a mold, and a surface having patterns of the film being in contact with the inner wall of the mold; introducing a molten thermoplastic resin into the mold to form a resin layer on the film; cooling the resin layer to combine with the film to form a cover. However, the surface with patterns of such cover is exposed on the exterior, as a result, the patterns are prone to be scratched, thus appearance of cover is influenced in use. Furthermore, if the covers require vivid appearances by compounding multiple patterns and colors, the above methods for manufacturing the cover are hardly achieved. 
         [0005]    Therefore, what is needed is to provide a cover that can tend give various and vivid appearances whilst also having good performance, and a method for manufacturing the same. 
       SUMMARY 
       [0006]    A cover according to a preferred embodiment includes a base, a patterned layer, a protective layer and a bottom layer. The base has a first surface, and a second surface on the opposite side of the first surface. The patterned layer is formed on the first surface of the base. The protective layer and the bottom layer are integrally formed on the second surface of the base and on the patterned layer respectively by injection molding. 
         [0007]    A method for manufacturing a cover according to another preferred embodiment includes the following steps: providing a base, which has a first surface, and a second surface on the opposite side of the first surface; forming a patterned layer on the first surface of the base; forming a protective layer on the second surface of the base by injection molding; and forming a bottom layer on the patterned layer by injection molding. 
         [0008]    Other advantages and novel features will become more apparent from the following detailed description of the preferred embodiments, when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Many aspects of the present cover and a method for manufacturing the same can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the cover and a method for manufacturing the same. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0010]      FIG. 1  is a schematic, cross-sectional view of a cover according to a preferred embodiment; 
           [0011]      FIG. 2  a flow chart of a method for manufacturing the cover of  FIG. 1 ; 
           [0012]      FIG. 3  is a schematic, cross-sectional view of a base of  FIG. 1 ; 
           [0013]      FIG. 4  is a schematic, cross-sectional view of the base and a patterned layer on the base of  FIG. 1 ; 
           [0014]      FIG. 5  is a schematic, cross-sectional view of the base having the patterned layer and a coating layer thereon of  FIG. 1 ; 
           [0015]      FIG. 6  is a schematic, cross-sectional view of the base having the patterned layer thereon after molding of  FIG. 1 ; 
           [0016]      FIG. 7  is a schematic, cross-sectional view of an apparatus in the period of forming a protective layer for manufacturing the cover of  FIG. 1 ; 
           [0017]      FIG. 8  is a schematic, cross-sectional view of an apparatus in the period of forming a bottom layer for manufacturing the cover of  FIG. 1 ; 
           [0018]      FIG. 9  is a schematic, cross-sectional view of an apparatus in the period of forming the bottom layer before forming the protective layer for manufacturing the cover of  FIG. 1 ; and 
           [0019]      FIG. 10  is a schematic, cross-sectional view of an apparatus in the period of forming the protective layer after forming the bottom layer for manufacturing the cover of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]    Reference will now be made to the drawings to describe preferred embodiments of the present cover and method for manufacturing the same, in detail. 
         [0021]    Referring to  FIG. 1 , a cover  10  according to a first preferred embodiment is shown. The cover  10  includes a protective layer  11 , a base  12 , a patterned layer  13 , and a bottom layer  14 . A first surface  121  and a second surface  122  are on opposite sides of the base  12 . The patterned layer  13  is formed on the first surface  121  of the base  12 . The protective layer  11  and the bottom layer  14  are integrally formed on the second surface  122  and the patterned layer  13  respectively by injection molding. 
         [0022]    The base  12  is a sheet or a film. A material of the base  12  is selected from a group consisting of polycarbonate, acrylonitrile-butadiene-styrene terpolymer, polyvinyl chloride, polyamide, and polymethyl methacrylate. 
         [0023]    The patterned layer  13  is used to provide patterns or colors of the cover. The patterned layer  13  is made up of printing ink layer, metal plated layer, or any combination thereof. Since the patterned layer  13  can be produced independently on the base  12 , the patterned layer  13  may be prepared to have predetermined colors or patterns; thus, the cover  10  can exhibit complex and vivid appearances easily. 
         [0024]    The protective layer  11  is to be exposed on the exterior, thus the protective layer  11  is configured to be translucent, semi-transparent, or transparent for the visualization of the patterned layer  13  on the base  12 . A material of the protective layer  11  is selected from a group consisting of polycarbonate, acrylonitrile-butadiene-styrene terpolymer, and polymethyl methacrylate. 
         [0025]    The bottom layer  14  mainly employs plastic. For example, the plastic is selected from a group consisting of polycarbonate, acrylonitrile-butadiene-styrene terpolymer, polyvinyl chloride, polyethylene, polystyrene, polyamide, and any combination thereof. 
         [0026]    In use, the protective layer  11  and bottom layer  14  cooperatively protect the base  12  and the patterned layer  13 . Therefore, the cover  10  has a relatively long operational life because the patterned layer  13  is prevented from being distorted or scratched. 
         [0027]    Further, to prevent the patterned layer  13  from being distorted during the process of forming the protective layer  11  or bottom layer  14 , the cover  10  includes a coating layer  15  between patterned layer  13  and bottom layer  14 . A material of the coating layer  15  is selected from a group consisted of polyamide, polystyrene and polypropylene. 
         [0028]    Referring to  FIG. 2 , a flow chart of a method for manufacturing the cover  10  is shown. The method includes following steps of: 
         [0029]    step  100 : also referring to  FIG. 3 , providing the base  12  having the first surface  121 , and the second surface  122  on opposite sides thereof; 
         [0030]    step  200 : also referring to  FIG. 4 , forming the patterned layer  13  on the first surface  121  of the base  12 ; 
         [0031]    step  300 : forming the protective layer  11  on the second surface  122  of the base  11  by injection molding; and 
         [0032]    step  400 : forming the bottom layer  14  on the patterned layer  13  by injection molding. 
         [0033]    In step  100 , the base  12  is a sheet or a film. A material of the base  12  is selected from a group consisting of polycarbonate, acrylonitrile-butadiene-styrene terpolymer, polyvinyl chloride, polyamide, and polymethyl methacrylate. 
         [0034]    In step  200 , forming the patterned layer  13  is performed by electroplating, evaporation, sputtering, or printing. Preferably, the patterned layer is prepared by printing, for example, screen printing. 
         [0035]    Further, referring to  FIG. 5  after forming the patterned layer  13 , a coating resin is applied on the patterned layer  13  after step  200 , thereby forming a coating layer  15  to prevent the patterned layer  13  from distortions while forming the protective layer  11  and bottom layer  14 . The coating resin is selected from a group consisted of polyamide, polystyrene and polypropylene. 
         [0036]    Referring to  FIG. 6 , according to a predetermined shape of the cover  10 , the base  12  having the patterned layer  13  thereon can further be molded or trimmed to a suitable shape, before forming the protective layer  11  in step  300 . The step of molding is carried out by hot press molding. 
         [0037]    In step  300 , forming the protective layer  11  on the second surface  122  includes following steps of: referring to  FIG. 7 , providing a mold  20  that includes an upper molding portion  201  and a lower molding portion  202 , the lower molding portion  202  has a molding block  2021 , the upper molding portion  201  defines a molding cavity  2011  that substantially conforms to the molding block  2021 , and further defines a guiding channel  2012  that communicates with the molding cavity  2011  above the molding cavity  2011 ; setting the semi finished cover on the molding block  2021 ; fastening the upper molding portion  201  and the lower molding portion  202  together; introducing a first resin  110  from the guiding channel  2012  onto the second surface  122 , thereby forming the protective layer  11 . The first resin  110  is selected from a group consisting of polycarbonate, acrylonitrile-butadiene-styrene terpolymer, and polymethyl methacrylate. 
         [0038]    In step  400 , forming the bottom layer  14  on the patterned layer  13  includes following steps of: referring to  FIG. 8 , providing a mold  30  that includes an upper molding portion  301  and a lower molding portion  302 , the lower molding portion  302  has a molding block  3021  and further defines a guiding channel  3022  in the molding block  3021 , the upper molding portion  301  defines a molding cavity  3011  that substantially conforms to the molding block  3021 ; setting the semi finished cover that has formed the protective layer  11  on the molding cavity  3011 ; fastening the upper molding portion  301  and the lower molding portion  302  together; introducing a second resin  140  from the guiding channel  3022  onto the patterned layer  13 , thereby forming the bottom layer  14 . In addition, if the patterned layer  13  has the coating layer  15  thereon, the second resin  140  is introduced onto the coating layer  15 . The second resin  140  is selected from a group consisting of polycarbonate, acrylonitrile-butadiene-styrene terpolymer, polyvinyl chloride, polyethylene, polystyrene, polyamide, and any combination thereof. 
         [0039]    Alternatively, referring to the  FIGS. 9 and 10 , according to an aspect of the embodiment, the order of step  300  and step  400  can be exchanged. Also, according to another aspect of the embodiment, using a different mold, the step  300  and step  400  can be carried out simultaneously. 
         [0040]    While the present invention has been described as having preferred or exemplary embodiments, the embodiments can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the embodiments using the general principles of the invention as claimed. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and which fall within the limits of the appended claims or equivalents thereof.