Abstract:
A housing with a three dimensional pattern coating includes a substrate, a powder coated layer formed on the substrate, the powder coated layer having plural grooves therein; and a pattern coating formed in the grooves. A method for making the housing comprises: providing a substrate; painting a powder coated layer onto the substrate; etching the powder coated layer to form plural grooves; filling the grooves with a colloidal solution.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to housings, especially to a housing having a three dimensional pattern coating and a manufacturing method thereof. 
         [0003]    2. Description of Related Art 
         [0004]    Portable electronic devices commonly employ a variety of decorative housings to attract consumers. Some of the housings are made of metal. These metal housings may be coated with paint or ink to provide a decorative appearance. Typically, paint can be applied to the surface of the metal housings by oil paint spray or electrostatic powder coating. In a powder coating paint operation, the powder paint is at a high rate of paint recovery, and the whole process is environmentally friendly due to the non-volatilizing of the powder paint. So, the powder paint is widely used to form coatings onto the surfaces of the housings. 
         [0005]    A logo or a symbolical pattern is usually formed on the surface of the coatings by printing. The logo or symbolical pattern can not present three dimensional appearance because of its thin thickness. In addition, the logo or symbolical pattern formed by printing has poor adhesion to the coatings, and is prone to be abraded. 
         [0006]    Therefore, there is room for improvement within the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    Many aspects of the housing with a three dimensional pattern coating 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 housing with a three dimensional pattern coating. Moreover, in the drawing like reference numerals designate corresponding parts throughout the several views. 
           [0008]      FIG. 1  is a cross-sectional view of a present embodiment of a housing with a three dimensional pattern coating. 
           [0009]      FIG. 2  is a flow chart of a present embodiment of a method for making the housing shown in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    Referring to  FIG. 1 , in a present exemplary embodiment, a housing  10  includes a substrate  11 , a powder coated layer  13  formed on one surface of the substrate  11 , and a pattern coating  15  formed in the powder coated layer  13 . 
         [0011]    The substrate  11  is made of metal selected from a group consisting of aluminum, aluminum alloy, magnesium, magnesium alloy, titanium, and titanium alloy. 
         [0012]    The powder coated layer  13  is formed on one surface of the substrate  11  by electrostatic powder coating with solid powder paint. The solid powder paint may be polyurethane resin or epoxy resin. The thickness of the powder coated layer  13  is about 60-90 μm. Some grooves  14  are formed in the powder coated layer  13  by laser etching. The grooves  14  define a desired logo or a decorative pattern of electronic devices. The depth of the grooves  14  can either be equal to or less than the thickness of the powder coated layer  13 . 
         [0013]    The pattern coating  15  is formed by filling colloidal solution into the grooves  14 . The colloidal solution contains acrylic acid resin, a leveling agent, a solidifying agent, and an organic solvent. The organic solvent may be benzene, toluene, or xylene. The colloidal solution may further contain pigment. The colloidal solution possesses good leveling characteristic, and can be uniformly filled into the grooves  14 . The colloidal solution filled in the grooves  14  can be solidified in an oven. As such, the pattern coating  15  is obtained. The pattern coating  15  presents three dimensional appearance. The thickness of the pattern coating  15  may be less than the thickness of the powder coated layer  13 . 
         [0014]    A method for making the housing  10  is provided. Referring to  FIG. 2 , the method comprises steps  20  to steps  50 . In step  20 , the substrate  11  made of metal selected from a group consisting of aluminium, aluminium alloy, magnesium, magnesium alloy, titanium, or titanium alloy is provided. 
         [0015]    In step  30 , a powder coated layer  13  is formed on one surface of the substrate  11 . The method of forming powder coated layer  13  onto the substrate  11  may be electrostatic powder coating with solid powder paint. Prior to the coating step, the substrate  11  may be treated with sand blasting to roughen its surface to enhance the adhesion of the powder coated layer  13  to the substrate  11 . The solid powder paint used in forming powder coated layer  13  may be polyurethane resin or epoxy resin. The thickness of the powder coated layer  13  is about 60-90 μm. 
         [0016]    In step  40 , plural grooves  14  are formed in the powder coated layer  13  by etching. The etching step is carried out by using a laser beam to shoot to the powder coated layer  13  in a designed pattern. As such, the grooves  14  are obtained. The depth of the grooves  14  may be equal to the thickness of the powder coated layer  13 . 
         [0017]    In step  50 , pattern coating  15  is formed by filling the grooves  14  with colloidal solution. The colloidal solution may be acrylic acid resin colloidal solution. The colloidal solution may further comprise leveling agent, solidify agent, and organic solvent. The organic solvent may be benzene, toluene, and xylene. The colloidal solution can also contain pigment. Filling the grooves  14  may be carried out by using an injector injecting the colloidal solution into the grooves  14 . The colloidal solution is at a low viscidity, it can be uniformly filled in the grooves  14 . After the grooves  14  are filled, the housing  10  is baked in an oven at about 200° C. to solidify the colloidal solution. As such, the pattern coating  15  is obtained. The surface of the pattern coating  15  may be on the same plane with the surface of the powder coated layer  13 . 
         [0018]    It should be understood, the depth of the grooves  14  formed on the powder coated layer  13  can also be less than the thickness of the powder coated layer  13 . 
         [0019]    It should be understood, the surface of the pattern coating  15  can also be at a lower elevation than the surface of the powder coated layer  13 . 
         [0020]    The housing  10  prepared via the above method has a three dimensional pattern coating  15 . The pattern coating  15  would not be easily abraded because its surface is either on the same plane with or lower than the surface of the powder coated layer  13 . The method of making the housing  10  utilizes laser beam to etch the powder spay coating  13  to form grooves  14 , which has a higher efficiency at recomposing the grooves  14  depended to the product design required. 
         [0021]    The housing  10  disclosed in the present disclosure may be a mobile phone, a game player, or a camera. The housing  10  can also be a container or a cover of a container. 
         [0022]    It should be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.