Patent Publication Number: US-2013241867-A1

Title: Capacitive touch panel and apparatus for manufacturing same

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a capacitive touch panel and an apparatus for manufacturing the capacitive touch panel. 
     2. Description of Related Art 
     The capacitive touch panels are made from glasses, thus are fragile and easily damaged. This characteristic also leads to difficulties in manufacturing. 
     Therefore, it is desirable to provide a capacitive touch panel and an apparatus for manufacturing same that can overcome the above-mentioned limitations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the embodiments 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 present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is a schematic, explode view of a capacitive touch panel, according to a first exemplary embodiment. 
         FIG. 2  is a schematic, assembled view of the capacitive touch panel of  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the capacitive touch panel of  FIG. 2 , taken along a line III-III. 
         FIG. 4  is a schematic view of an apparatus for manufacturing the capacitive touch panel, according to a second exemplary embodiment, wherein the apparatus includes a first pressing roller, a second pressing roller and a third pressing roller. 
         FIG. 5  is a schematic view of the first pressing roller of  FIG. 4 . 
         FIG. 6  is a schematic view of the third pressing roller of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-3  illustrate a capacitive touch panel  100  in accordance to a first embodiment. The capacitive touch panel  100  includes a flexible substrate  10 , a first sensing layer  20 , a first protective film  30 , a second sensing layer  40 , and a second protective film  50 . 
     The substrate  10  includes a first surface  101  and a second surface  102  opposite to the first surface  101 . The substrate  10  can be made of polyethylene terephthalate (PET), polyethersulfone (PES) or other flexible transparent material. 
     The first sensing layer  20  is formed on the first surface  101 , and the first protective film  30  is positioned on the first sensing layer  20 . The second sensing layer  40  is formed on the second surface  102 , and the second protective film  50  is positioned on the second sensing layer  40 . 
     The first sensing layer  20  includes a first cladding portion  21  and a first conductive portion  23 . The first cladding portion  21  defines a first receiving groove  22 . The first conductive portion  23  is received in the receiving groove  22  and is coupled with the receiving groove  22 . In this embodiment, the first cladding portion  21  is made of ultraviolet glue, the first conductive portion  23  is made of conductive macromolecule material, such as Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) (PEDOT:PSS). 
     The second sensing layer  40  includes a second cladding portion  41  and a second conductive portion  43 . The second cladding portion  41  defines a second receiving groove  42 . The second conductive portion  43  is received in the second receiving groove  42  and is coupled with the second receiving groove  42 . In this embodiment, the material of the first cladding portion  21  is substantially the same as the material of the second cladding portion  41 , and the material of the second conductive portion  43  is substantially the same as the material of the first conductive portion  23 . 
     The first protective film  30  and the second protective film  50  are made of insulating material, such as silicon nitride or plastic. 
     Referring to  FIG. 4 , an apparatus  200  for making the capacitive touch panel  100  includes a release reel  201  and a film retracting reel  202 . The apparatus  200  further includes a first roller pressing device  210 , a second roller pressing device  220 , a third roller pressing device  230 , a fourth roller pressing device  240 , a fifth roller pressing device  250 , and a sixth roller pressing device  260  in order along a transmission direction of the substrate  10 . 
     One end of the substrate  10  is wound around the releasing reel  201 , and the other end of the substrate  10  is fixed to the film retracting reel  202 . The first roller pressing device  210  is used for forming the first cladding portion  21  with the first receiving groove  22  on the first surface  101 . The second roller pressing device  220  is used for filling a first conductive portion forming solvent in the first receiving groove  22  to form the first conductive portion  23 , and thus to obtain the first sensing layer  20  The first conductive portion forming solvent is a solvent for forming the first conductive portion  23 . 
     The third roller pressing device  230  is used for forming the first protective film  30  on the first sensing layer  20 . The fourth pressing device  240  is used for forming the second cladding portion  41  with the second receiving groove  42  on the second surface  102 . The fifth pressing device  250  is used for filling a second conductive portion forming solvent in the second receiving groove  42  to obtain the second conductive portion  43 , and thus to obtain the second sensing layer  40 . The sixth roller pressing device  260  is used for forming the second protective film  50  on the second sensing film  40 . 
     In detail, the first roller pressing device  210  includes a first transmission roller  211 , a first feeder  212 , a first auxiliary roller  213 , a first pressing roller  214 , a second auxiliary roller  215 , and a first drying element  219 . The first auxiliary roller  213  and the second auxiliary roller  215  are positioned on two opposite sides of the first pressing roller  214 . A first molding channel  216  is formed between the first auxiliary roller  213  and the first pressing roller  214 . A second molding channel  217  is formed between the second auxiliary roller  215  and the first pressing roller  214 . The first feeder  212  is positioned above the first auxiliary roller  213  and is used for providing the first cladding portion forming solvent to the first surface  101  of the substrate  10 . The first auxiliary roller  213  has a smooth rolling surface  213   a.  The second auxiliary roller  215  has a smooth rolling surface  215   a.    
     Referring also to  FIG. 5 , the first pressing roller  214  has a rolling surface  214   b  defining a first impression pattern  214   a  mating with the first receiving groove  22 . The rotating direction of the first auxiliary roller and the second auxiliary roller are the same as each other and is opposite to the rotating direction of the first pressing roller  214 . In this embodiment, the first auxiliary roller  213  and the second auxiliary roller  215  are rotated clockwise, and the first pressing roller  214  is rotated counterclockwise. The first drying element  219  is positioned under the first pressing roller  214 . The first cladding portion forming solvent is ultraviolet glue, the first drying element  219  is an ultraviolet source, and the first feeder  212  is a precision slot die. 
     The substrate  10  extends from a lower edge of the first transmission roller  211  to a higher edge of the first auxiliary roller  213 . The first cladding portion forming solvent is then uniformly distributed by the first feeder  212 , and passes through the first channel  216  to form the first cladding portion solvent layer. The first drying element  219  solidifies the first cladding portion solvent layer to form the first cladding portion  21 . At last, the substrate  10  with the first cladding portion  21  passes through the second channel  217 . 
     The second roller pressing device  220  includes a second transmission roller  221 , a second feeder  222 , two first front rollers  223 , a second drying element  229 , and two first rear rollers  224 . Each of the two first front rollers  223  has a smooth rolling surface  223   a.  Each of the two first rear rollers  224  has a smooth rolling surface  224   a.  A third molding channel  226  is formed between the two first front rollers  223 . A fourth molding channel  227  is formed between the two first rear rollers  224 . In this embodiment, the second drying element  229  is a heater, and includes two heating sheets  228  parallel to each other. A lengthwise direction of each of the two heating sheets  228  is substantially the same as the transmission direction of the substrate  10 . A drying channel  229   a  is formed between the two heating sheets  228 . In this embodiment, the second feeder  222  is a spray printing head. 
     The substrate  10  with the first cladding portion  20  extends from a lower edge of the second transmission roller  221 , and then passes through the third molding channel  226 , the drying channel  229   a,  and the fourth molding channel  227 . The second feeder  222  provides a conductive portion forming solvent in the first receiving groove  22 . The conductive portion forming solvent is a solvent for forming the conductive portion  23 . 
     Each of the two first front rollers  226  and the two first rear rollers  227  has a smooth rolling surface. The two front rollers  226  are used for pressing the conductive portion forming solvent in the first receiving groove  22 . The second drying element  229  is used for solidifying the conductive portion forming solvent. The two first rear rollers  224  are used for pressing the solidified conductive portion forming solvent again to form the first conductive portion  23 , and thus to obtain the first sensing layer  20 . 
     The third roller pressing device  230  includes a second releasing reel  231 , a third transmission roller  232 , two second pressing rollers  233 , and a fourth transmission roller  236 . A fifth channel  234  is formed between the two second pressing rollers  233 . The first sensing layer  20  faces the third transmission roller  232 . The first releasing reel  231  is used for paying out a first protective film  30 . The first protective film  30  extends through a higher edge of the third transmission roller  232 , and then passes through the fifth molding channel  234 , and thus the first protective film  30  is pressed on the first sensing layer  20 . 
     The structure of the fourth pressing device  240  is the same as the structure of the first pressing device  210 , and includes a fifth transmission roller  241 , a third feeder  242 , a third auxiliary roller  243 , a third pressing roller  244 , and a fourth auxiliary roller  245  along the transmission direction of the substrate  10 . The fourth pressing device  240  further includes a third drying element  246  under the third pressing roller  244 . Referring also to  FIG. 6 , the third pressing roller  244  has a rolling surface with a second impression pattern  247  mating with the second receiving groove  42 . Each of the third auxiliary roller  243  and the fourth auxiliary roller  245  has a smooth rolling surface. In this embodiment, the third feeder  242  is a precision slot die. 
     The substrate  10  with the first sensing layer  20  and the first protective film  30  extends from a higher edge of the third auxiliary roller  243 , and is coated with a second cladding portion forming solvent on the second surface  102  by the third feeder  242 . The second cladding portion forming solvent coated substrate  10  then passes through a molding channel between the third auxiliary roller  243  and the third pressing roller  244  to a lower edge of the third pressing roller  244 , and is solidified by the third drying element  246 , at last passes through a molding channel between the fourth auxiliary roller  245  and the third pressing roller  244  to form a second cladding portion  41  on the second surface  102 . In this embodiment, the second cladding portion forming solvent is ultraviolet glue. 
     The structure of the fifth pressing device  250  is substantially the same as the structure of the second pressing device  220 , and includes a sixth transmission roller  251 , a fourth feeder  252 , two second front rollers  253 , a forth drying element  254 , and two second rear rollers  256 . The substrate  10  with the first sensing layer  20 , the first protective film  30 , and the second cladding portion  41  extends through a lower edge of the sixth transmission roller  251 , is filled with a second conductive portion forming solvent in the second receiving groove  42  by the fourth feeder  252 , then passes through a molding channel between the two second front rollers  253 , a drying channel of the fourth drying element  254 , and a molding channel between the two second rear rollers  256  to obtain the second sensing layer  40 . In this embodiment, the fourth feeder  252  is a spray printed head, and the second conductive portion forming solvent is PEDOT:PSS solvent. 
     The structure of the sixth pressing device  260  is substantially the same as the structure of the third pressing device  230 , and includes a third releasing reel  261 , a seventh transmission roller  262 , two fourth pressing rollers  263 , and an eighth transmission roller  264 . The second sensing layer  40  faces the seventh transmission roller  262 . The third releasing roller  261  is used for providing the second protective film  50 . The second protecting film  50  extends through the higher edge of the seventh transmission roller  262 , and a molding channel between the two fourth pressing rollers  263  to press the second protective film  50  on the second sensing layer  40 , and thus to obtain the capacitive touch panel  100 . The eighth transmission roller  264  transmits the formed capacitive touch panel  100  to the film retracting reel  202 . The film retracting reel  202  takes up the formed capacitive touch panel  100 . Then, the formed capacitive touch panel  100  can be cut to a predetermined size as required. 
     In this embodiment, the apparatus  200  further includes a supporting roller  204 . The fourth transmission roller  236  is used for transmitting the substrate  10  with the first protective film  30  to the supporting roller  204 . The supporting roller  204  is used for transmitting the substrate  10  with the first protective film  30  to the fourth pressing device  240 , and making the second surface  102  facing the third pressing roller  244 . 
     In other embodiments, the first to eight transmission rollers, the two first rear rollers and the two second rear rollers can be omitted. 
     The above particular embodiments are shown and described by way of illustration only. The principles and the features of the present disclosure may be employed in various and numerous embodiments thereof without departing from the scope of the disclosure as claimed. The above-described embodiments illustrate the scope of the disclosure but do not restrict the scope of the disclosure.