Abstract:
An adhesive tape is non-permanent before pressing and heating includes a protective layer, an adhesive layer formed on the protective layer, and a plurality of adhesive particles dispersed on the adhesive layer. The adhesive force of the adhesive particles is less than that of the adhesive layer. The adhesive tape is easily peeled off from a workpiece to allow reworking before final bonding is required.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to adhesive tapes and particularly to an adhesive tape which can be easily peeled off. 
         [0003]    2. Description of the Related Art 
         [0004]    In an assembling process of consumer electronics, an adhesive tape is employed to bond two workpieces together. The adhesive tape should have a good adhesive force to bond the workpieces together strongly. At the same time, the adhesive tape should be easily peeled off from the two workpieces when a reworking or another process is required. 
         [0005]    Therefore, there is room for improvement within the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout several views. 
           [0007]      FIG. 1  shows one embodiment of an adhesive tape adhered to a workpiece in a first state. 
           [0008]      FIG. 2  is similar to  FIG. 1 , but showing the adhesive tape adhered to the workpiece in a second state. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean “at least one.” 
         [0010]      FIG. 1  shows a first embodiment of an adhesive tape  100 . The adhesive tape  100  includes a protective layer  10 , an adhesive layer  20  formed on the protective layer  10 , and a plurality of adhesive particles  30  dispersed on the adhesive layer  20 . The protective layer  10  is made of releasing or non-stick paper or material, such as plastic film or kraft. An adhesive force of the adhesive layer  20  is greater than an adhesive force of the adhesive particles  30 . In an illustrated embodiment, the adhesive force of the adhesive layer  20  is equal to or higher than about 1.5 kilogram per inch (kg/in). The adhesive force of the adhesive particles  30  at saturation density is in a range from about 0.1 kg/in to about 1.0 kg/in. The dispersed density of the adhesive particles  30  can be adjusted as needed. In the illustrated embodiment, the adhesive particles  30  are uniformly dispersed on the adhesive layer  20  by a spraying method. The size of each adhesive particle  30  is in a range from about 0.1 micrometers (μm) to about 100 μm. The dispersed density of the adhesive particles  30  is in a range from about 10% to about 80%. 
         [0011]    In use, the adhesive particles  30  make first contact with a workpiece  200 , and the bonding strength between the adhesive tape  100  and the workpiece  200  is relatively low, such that the adhesive tape  100  is easily peeled off from the workpiece  200  (referring to  FIG. 1 ). The adhesive tape  100  is then pressed or/and heated, and the adhesive layer  20  penetrates through the adhesive particles  30  to the workpiece  200  via gaps between the adhesive particles  30  and after a predetermined time span will adhere to the workpiece  200  with full bonding strength (refer to  FIG. 2 ). The predetermined time span is defined as a reworking time span, during which time span the adhesive tape  100  is easily peeled off, and the workpiece  200  is again available for reworking 
         [0012]    The reworking time span can be adjusted by adjusting a pressure exerted on the adhesive tape  100 , by a heating temperature, by the size of each adhesive particle  30 , and the dispersed density of the adhesive particles  30 . An original viscosity of the adhesive tape  100  and a final viscosity of the adhesive tape  100  can be adjusted by the dispersed density of the adhesive particles  30 . 
         [0013]    To illustrate how the heating temperature, the size of each adhesive particle  30 , and the dispersed density of the adhesive particles  30  can adjust the reworking time span, four examples are listed in table 1 below. No pressure is exerted on the adhesive tape  100  in the four examples. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Properties of the Adhesive Tape 
               
             
          
           
               
                   
                   
                   
                 Heating 
                 Rework 
                 Original 
                 Final 
               
               
                   
                   
                 Dis- 
                 temperature 
                 time 
                 vis- 
                 vis- 
               
               
                   
                 size 
                 persing 
                 (degree 
                 span 
                 cosity 
                 cosity 
               
               
                 Example 
                 (μm) 
                 density 
                 Celsius) 
                 (hour) 
                 (Kg/in) 
                 (Kg/in) 
               
               
                   
               
             
          
           
               
                 Example 1 
                 8 
                 50 
                 25 
                 24 
                 0.6 
                 1.6 
               
               
                 Example 2 
                 15 
                 30 
                 40 
                 18 
                 0.8 
                 2.0 
               
               
                 Example 3 
                 15 
                 40 
                 40 
                 22 
                 0.5 
                 1.9 
               
               
                 Example 4 
                 6 
                 20 
                 25 
                 10 
                 1.2 
                 2.5 
               
               
                   
               
             
          
         
       
     
         [0014]    When the adhesive tape  100  is adhered to the workpiece  200  at an initial state (a first state), only the adhesive particles  30  having a low adhesive force adhere to the workpiece  100 , so that the adhesive tape  100  is easily peeled off from the workpiece. When the adhesive layer  20  permeates the adhesive particles  30  via the gaps between the adhesive particles  30  and adheres to the workpiece  100 , the bonding strength between the adhesive tape  100  and the workpiece  200  is improved and increases over time. In addition, the reworking time span can be easily adjusted by adjusting the pressure exerted on the adhesive tape  100 , a heating temperature, the size of each adhesive particle  30 , and the dispersed density of the adhesive particles  30 . 
         [0015]    It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in the matters of shape, size, and arrangement of parts within the principles of the embodiments to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.