Abstract:
Disclosed is a touch panel. The touch panel includes a transparent window; a printed pattern disposed under the transparent widow and spaced apart from the transparent window; and an intermediate layer between the transparent window and the printed pattern.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit under 35 U.S.C. §119 of Korean Patent Application No. 10-2011-0139805, filed Dec. 22, 2011, which is hereby incorporated by reference in its entirety. 
       BACKGROUND 
       [0002]    The embodiment relates to a printed pattern structure of a touch panel. 
         [0003]    A touch panel is installed on a display surface of an image display device such as a cathode ray tube (CRT), a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electro-luminescence device (ELD), so that a user inputs predetermined information into a computer by pressing the touch panel while viewing the image display device. 
         [0004]      FIGS. 1 and 2  are views showing main components of a capacitive type touch panel.  FIG. 1  is a plan view showing a multi-layer bonding structure, and  FIG. 2  is a sectional view taken along a line X of  FIG. 1 . Referring to  FIGS. 1 and 2 , the touch panel generally includes an upper optical clear adhesive (OCA)  50  provided under a transparent window  10 , and an upper electrode layer (ITO)  40 , a lower OCA  30 , and a lower electrode layer  20  provided under the upper OCA  50 . In addition, a liquid crystal panel  60  adheres to the bottom surface of the above structure. A touch screen panel TSP formed by bonding various layers to each other has a bonding area C which is formed by cutting the upper OCA  50 , the upper electrode layer (ITO)  40 , and the lower OCA  30  for the purpose of bonding to an FPCB module and exposes a connection pad P. 
         [0005]    The above touch panel includes a printed pattern implemented to represent various colors depending on the design of a terminal or to hide internal wirings. The printed pattern needs to be directly printed on the bottom surface of the transparent window  10 , to represent superior shielding characteristic, and to have no pin-hole, protrusion, and dent. 
         [0006]    However, in the related art, since a printed pattern is formed on the transparent window  10  by performing printing works at least five times, an electrode wire, an insulating layer, or an electrode pattern is deformed or shorted due to step difference in printing works, or uniformity is degraded so that failure occurs. 
       BRIEF SUMMARY 
       [0007]    The embodiment provides a touch panel capable of reducing failure of an expensive transparent window to improve productivity by diminishing printing failure of a printed pattern by forming the printed pattern on an electrode layer of a touch panel, rather than the transparent window, and then bonding the printed pattern to the transparent window. 
         [0008]    According to the embodiment, there is provided a touch panel including: a transparent window; a printed pattern disposed under the transparent widow and spaced apart from the transparent window; and an intermediate layer between the transparent window and the printed pattern. 
         [0009]    The intermediate layer may include a sensing electrode pattern layer or an adhesive material layer. 
         [0010]    The intermediate layer may include a plurality of sensing electrode pattern layers, and the printed pattern may be formed on the sensing electrode pattern layer which is not adjacent to the transparent window among the sensing electrode pattern layers. 
         [0011]    The adhesive material layer may include a Pressure Sensitive Adhesive (PSA) or an Optical Clear Adhesive (OCA). 
         [0012]    The sensing electrode pattern layer may be formed at both surfaces of an insulating layer. 
         [0013]    The printed pattern may be disposed at a non-active region of the touch panel. 
         [0014]    According to the embodiment, failure of the expensive transparent window is reduced to improve productivity by diminishing printing failure of a printed pattern by forming the printed pattern on an electrode layer of a touch panel, rather than the transparent window, and then bonding the printed pattern to the transparent window. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIGS. 1 and 2  are views showing main components of a capacitive type touch panel. 
           [0016]      FIG. 3  is a sectional view illustrating a touch panel according to a first embodiment. 
           [0017]      FIG. 4  is a sectional view illustrating a touch panel according to a second embodiment. 
           [0018]      FIG. 5  is a sectional view illustrating a touch panel according to a third embodiment. 
           [0019]      FIG. 6  is a sectional view illustrating a touch panel according to a fourth embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Hereinafter, a touch panel according to an exemplary embodiment will be described with reference to the accompanying drawings in detail. Detailed descriptions of well-known functions and structures incorporated herein may be omitted when they make the subject matter rather unclear. The size of the elements shown in the drawings may be exaggerated for the purpose of explanation and may not utterly reflect the actual size. 
         [0021]      FIG. 3  is a sectional view illustrating a touch panel according to a first embodiment. The touch panel according to a first embodiment is described with reference to  FIG. 3 . 
         [0022]    Referring to  FIG. 3 , a protective substrate  110  is disposed at the uppermost portion of the touch panel. The protective substrate  110  may be a transparent window. 
         [0023]    As shown in  FIG. 3 , an intermediate layer is formed at a lower portion of the transparent window  110 . In the embodiment of  FIG. 3 , the intermediate layer is prepared as a first adhesive material layer  120 . The first adhesive material layer  120  may be configured by a Pressure Sensitive Adhesive (PSA) or an OCA. 
         [0024]    A first sensing electrode pattern layer  140  is formed at a lower portion of the first adhesive material layer  120  serving as the intermediate layer, and the printed pattern  130  is disposed on the sensing electrode pattern layer  140 . 
         [0025]    That is, the printed pattern  130  is formed at a side of the sensing electrode pattern portion  100 , rather than a side of the transparent window  110 . In detail, the printed pattern  130  is not formed on the side of the transparent window  110 , but formed at the side of the touch panel  100  including the first sensing electrode pattern layer  140 , a first PET substrate  150 , a second adhesive material layer  121 , a second sensing electrode pattern layer  141 , and a second PET substrate  151 , and the transparent windows  110  is bonded to the touch panel  100  by the first adhesive material layer  120 . 
         [0026]    The first sensing electrode pattern layer  140  is disposed on the first PET substrate  150 , and the second sensing electrode pattern layer  141  is disposed on the second PET substrate  151 . The second PET substrate  151  may be bonded to the first PET substrate  150  through the second adhesive material layer  121 . 
         [0027]    In the embodiment of  FIG. 3 , the printed pattern  130  is disposed on the first sensing electrode pattern layer  140 . 
         [0028]      FIG. 4  is a sectional view illustrating a touch panel according to a second embodiment. 
         [0029]    As shown in  FIG. 4 , an intermediate layer is formed at a lower portion of a transparent window  110 . In the same manner as the embodiment of  FIG. 3 , the intermediate layer is prepared as the first adhesive material layer  120 . The first adhesive material layer  120  may be configured by a Pressure Sensitive Adhesive (PSA) or an OCA. 
         [0030]    The first PET substrate  150  is disposed at a lower portion of the first adhesive material layer  120  serving as the intermediate layer, the first sensing electrode pattern layer  140  is disposed at a lower portion of the first PET substrate  150 , and the second adhesive material layer  121  is formed at a lower portion of the first sensing electrode pattern layer  140 . The second PET substrate  151  and the second sensing electrode pattern layer  141  are sequentially formed under the second adhesive material layer  121  formed as described above. 
         [0031]    That is, in the embodiment shown in  FIG. 4 , a formation order of respective layers of the touch panel is inversed to that of the embodiment shown in  FIG. 3 . However, similar to the embodiment of  FIG. 3 , the printed pattern  130  is formed at a side of the touch panel  100  other than a side of the transparent window  110 , and a first sensing electrode pattern layer  140  of the touch panel  100  is bonded to the transparent window  110  through the first adhesive material layer  120 . 
         [0032]    In the embodiment of  FIG. 4 , the printed pattern  130  is disposed on the first PET substrate  150 . 
         [0033]      FIG. 5  is a sectional view illustrating a touch panel according to a third embodiment. 
         [0034]    As shown in  FIG. 5 , an intermediate layer is formed at a lower portion of a transparent window  110 . In the same manner as the embodiments of  FIGS. 3 and 4 , the intermediate layer is prepared as the first adhesive material layer  120 . The first adhesive material layer  120  may be configured by a PSA or an OCA. 
         [0035]    The sensing electrode pattern part  100  may be configured so that a first sensing electrode pattern layer  140  and a second sensing electrode pattern layer  141  are formed on a both surfaces of the PET substrate  150 , respectively, and the printed pattern  130  is disposed at a side of the first sensing electrode pattern layer  140  of the touch panel  100 . 
         [0036]    That is, similar to the embodiments of  FIGS. 3 and 4 , the printed pattern  130  is formed at a side of the touch panel  100  other than a side of the transparent window  110 , and a first sensing electrode pattern layer  140  of the touch panel  100  is bonded to the transparent window  110  through the first adhesive material layer  120  in the embodiment of  FIG. 5 . 
         [0037]    In the embodiment of  FIG. 5 , the printed pattern  130  is disposed on the first sensing electrode pattern layer  140 . 
         [0038]      FIG. 6  is a sectional view illustrating a touch panel according to a fourth embodiment. 
         [0039]    As shown in  FIG. 6 , an intermediate layer is formed at a lower portion of a transparent window  110 . In this case, a touch panel layer is disposed as the intermediate layer in the embodiment of  FIG. 6 . 
         [0040]    That is, the touch panel  100  includes a first sensing electrode pattern layer  140 , an insulating layer  160 , and a second sensing electrode pattern layer  140  and is bonded to a transparent window  110 , a printed pattern  130  is disposed on a PET substrate  150 , and the PET substrate  150  on which the printed pattern  130  is bonded to the sensing electrode pattern part  100  through an adhesive material layer  120 . 
         [0041]    That is, according to the embodiment of  FIG. 6 , the printed pattern  130  is disposed between the PET substrate  150  and the touch panel  100  including the first sensing electrode pattern layer  141  and the second sensing electrode pattern layer  140  other than on a transparent window  110 . 
         [0042]    That is, in the embodiment of  FIG. 6 , a printed pattern substrate  150  is further disposed at a lower portion of the transparent window  110 , and the printed pattern  130  is disposed on the printed pattern substrate  150 . 
         [0043]    As mentioned above, according to the embodiments, printing failure of a printed pattern can be diminished by forming the printed pattern on an electrode layer of a touch panel, rather than the transparent window, and then bonding the printed pattern to the transparent window. 
         [0044]    Although the exemplary embodiments of the present invention have been described, it is understood that the present invention should not be limited to these exemplary embodiments but various changes and modifications can be made by one ordinary skilled in the art within the spirit and scope of the present invention as hereinafter claimed.