Patent Publication Number: US-11647616-B2

Title: Display assembly and display device

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a national phase entry under 35 U.S.C. § 371 of International Application No. PCT/CN2020/094443, filed on Jun. 4, 2020, the entire content of which is incorporated herein by reference. 
     FIELD 
     The present application relates to the field of display technology, in particular to a display assembly and a display device. 
     BACKGROUND 
     As display components of electronic equipment, OLED display devices have been widely used in various electronic products, and an OLED display panel is an important component of a display device. To protect a drive integrated circuit chip (Drive IC) and a main flexible printed board (MFPC) of an OLED display module, generally a tape (IC Cover Tape) is attached to the upper parts of the MFPC and the Drive IC. At present, the IC Cover Tape is relatively simple in structural design, has a poor protective effect on the MFPC and the Drive IC, and cannot effectively guarantee the yield of the MFPC and the Drive IC. 
     SUMMARY 
     This application discloses a display assembly and a display device, with an objective of improving a protective effect on a drive integrated circuit chip and a flexible printed board, and increasing the yield of a display product. 
     To achieve the above objective, this application provides the following technical solution. 
     A display assembly includes a display module, a flexible printed board, an integrated circuit chip, and a composite tape. The integrated circuit chip and a binding portion of the flexible printed board are respectively in binding connection with the display module. 
     The composite tape is located in a binding area of the display module and is pasted on the integrated circuit chip and the flexible printed board; and the composite tape includes a conductive fabric layer and an insulating film layer. 
     The conductive fabric layer includes a first part and a second part, the first part being configured to cover the integrated circuit chip and the binding portion of the flexible printed board, and the second part being configured to cover at least part of a grounding portion of the flexible printed board. 
     The insulating film layer is located on a side of the conductive fabric layer facing the integrated circuit chip and the flexible printed board, the insulating film layer including a third part, which is located at the first part of the conductive fabric layer and covers the integrated circuit chip and the binding portion of the flexible printed board, and the insulating film layer avoiding the at least part of the grounding portion of the flexible printed board. 
     Optionally, the third part of the insulating film layer is configured to cover a border of the binding portion of the flexible printed board and completely cover the integrated circuit chip, and is adhered to the display module. 
     Optionally, the composite tape further includes: 
     a wave absorbing material layer located on a side of the insulating film layer away from the conductive fabric layer, and at the third part of the insulating film layer, and configured to cover the integrated circuit chip. 
     Optionally, the shape of the wave absorbing material layer is similar to that of the integrated circuit chip, and the wave absorbing material layer is configured to completely cover the integrated circuit chip. 
     Optionally, the composite tape further includes: 
     a double-sided adhesive layer located on a side of the wave absorbing material layer away from the insulating film layer, an edge of the double-sided adhesive layer being beyond an edge of the wave absorbing material layer and being adhered to the insulating film layer. 
     Optionally, the grounding portion includes a first grounding portion close to the binding portion and a second grounding portion away from the binding portion. 
     The second part of the conductive fabric layer is configured to cover the first grounding portion and be adhered to the first grounding portion. 
     Optionally, the conductive fabric layer is configured to avoid the second grounding portion. 
     Optionally, the conductive fabric layer further includes a fourth part configured to cover a test portion of the flexible printed board. 
     The insulating film layer includes a fifth part located at the fourth part of the conductive fabric layer and configured to cover the test portion of the flexible printed board. 
     Optionally, the flexible printed board is L-shaped and includes a first extension portion and a second extension portion, the first extension portion including the binding portion, the test portion and the first grounding portion, and the second extension portion including the second grounding portion and a component portion. 
     The conductive fabric layer is configured to at least cover part of the first extension portion and avoid the second grounding portion and the component portion of the second extension portion. 
     The insulating film layer is configured to cover part of the first extension portion. 
     Optionally, in the first extension portion, the binding portion includes a one-layer metal wiring board, and an edge area on a side opposite to the binding portion includes a three-layer metal wiring board, and other areas include a six-layer metal wiring board; and the second extension includes a six-layer metal wiring board. 
     Optionally, the conductive fabric layer is configured such that an edge of a side thereof away from the binding portion of the flexible printed board is spaced from the component portion of the flexible printed board by a distance of 4.7 mm-4.8 mm, and edges of left and right sides thereof are spaced from borders of left and right sides of the flexible printed board by a distance of 1.2 mm-1.3 mm; and the borders of the left and right sides are borders of two ends in an extending direction of the first extension portion. 
     Optionally, the insulating film layer is made of a polyester film. 
     Optionally, the insulating film layer has a thickness of 0.009 mm-0.011 mm. 
     Optionally, the display module includes a flexible display panel, the flexible display panel having a binding area, which is bendable to the back of the display module. 
     The binding portion of the flexible printed board and the integrated circuit chip are respectively in binding connection with the binding area of the flexible display panel. 
     The composite tape covers part of the binding area of the flexible display panel and is adhered to the part of the binding area. 
     Optionally, the display module includes a display panel and a flexible connecting board with one end in binding connection with the display panel, the flexible connecting board having a binding area, which is bendable to the back of the display module. 
     The binding portion of the flexible printed board and the integrated circuit chip are respectively in binding connection with the binding area of the flexible connecting board. 
     The composite tape covers part of the binding area of the flexible connecting board and is adhered to the part of the binding area. 
     A display device including the display assembly in any of the above implementations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a structural diagram of a composite tape provided in an embodiment of the present application; 
         FIG.  2    is an exploded structural diagram of layers of the composite tape in  FIG.  1   ; 
         FIG.  3    is a structural diagram of a display assembly provided in an embodiment of the present application; 
         FIG.  4    is a partial structural diagram of the display assembly in  FIG.  3   ; 
         FIG.  5    is a structural diagram of a cross section along a direction A 1 -A 2 , and an enlarged diagram of part of the cross section, of the display assembly in  FIG.  3   ; 
         FIG.  6    is a structural diagram of a cross section along a direction B 1 -B 2 , and an enlarged diagram of part of the cross section, of the display assembly in  FIG.  3   ; 
         FIG.  7    is another structural diagram of a cross section along the direction A 1 -A 2  of the display assembly in  FIG.  3   . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Technical solutions in embodiments of this application will be described below clearly and completely in conjunction with the accompanying drawings in the embodiments of the application. Obviously, the described embodiments are only a part of embodiments of the application, and not all embodiments. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without any creative work fall within the protection scope of the application. 
     As shown in  FIGS.  1  to  4   , embodiments of the application provide a composite tape  1  configured to be adhered to a binding area of a display assembly. The display assembly includes a display module  4 , an integrated circuit chip  3 , and a flexible printed board  2 . The integrated circuit chip  3  and a binding portion  21  of the flexible printed board  2  are respectively in binding connection with the display module  4 . The composite tape  1  includes a conductive fabric layer  11  and an insulating film layer  12 . 
     The conductive fabric layer  11  includes a first part  11   a  and a second part  11   b . The first part  11   a  is configured to cover the integrated circuit chip  3  and the binding portion  21  of the flexible printed board  2 . The second part  11   b  is configured to cover at least part of a grounding portion (for example, a first grounding portion  22  in  FIGS.  3  and  4   ) of the flexible printed board  2 . In some embodiments, the grounding portion refers to a conductive part exposed to the outside that can be used for grounding, for example, a copper exposure portion. 
     The insulating film layer  12  is located on a side, facing the integrated circuit chip  3  and the flexible printed board  2 , of the conductive fabric layer  11 . The insulating film layer  12  includes a third part  12   c . The third part  12   c  is located at the first part  11   a  of the conductive fabric layer  11  and configured to cover the binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3 . The insulating film layer  12  avoids the at least part of the grounding portion (for example, the first grounding portion  22  in  FIGS.  3  and  4   ) of the flexible printed board  2 , that is, the insulating film layer  12  does not cover the above-mentioned at least part of the grounding portion. 
     The above-mentioned composite tape  1  has the conductive fabric layer  11  and the insulating film layer  12 . The insulating film layer  12  avoids the at least part of the grounding portion (for example, the first grounding portion  22  in  FIGS.  3  and  4   ) of the flexible printed board  2 . The second part  11   b  of the conductive fabric layer  11  may directly cover the at least part of the grounding portion (for example, the first grounding portion  22  in  FIGS.  3  and  4   ) of the flexible printed board  2 , thereby achieving electrical connection between the conductive fabric layer  11  and the flexible printed board  2 . Thus, on the one hand, the conductive fabric layer  11  can serve as an electromagnetic shielding layer to protect the flexible printed board  2  and the integrated circuit chip  3 , and on the other hand, it can be beneficial to achieving the grounding of both the flexible printed board  2  and the composite tape  1 . The insulating film layer  12  is located on the side of the conductive fabric layer  11  facing the integrated circuit chip  3  and the flexible printed board  2 , and the third part  12   c  of the insulating film layer  12  is configured to cover the binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3 . On the one hand, the binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3  can be isolated from the conductive fabric layer  11  to avoid a short circuit of the binding connection between the flexible printed board  2  or the integrated circuit chip  3  and the display module  4  due to the conductive fabric layer  11 . On the other hand, the insulating film layer  12  can isolate water vapor and prevent water vapor from invading binding areas of the flexible printed board  2  and the integrated circuit chip  3 , so that the yield of the binding connection can be effectively improved. 
     In summary, the above-mentioned composite tape  1  can improve a protective effect on the integrated circuit chip  3  and the flexible printed board  2 , and increase the binding yield of the integrated circuit chip  3  and the flexible printed board  2 , thereby increasing the yield of a display product. 
     In some embodiments, the conductive fabric layer  11  is a structural layer made of fibers which are pre-treated and electroplated with a metal coating to have metal properties. The insulating film layer  12  is a film layer with electrical insulation, high flexibility, and good waterproof performance, and for example may be of a polyester film material, such as Mylar. 
     Exemplarily, the thickness of the insulating film layer  12  may be about 0.01 mm. For example, it may be 0.009 mm-0.011 mm. 
     As shown in  FIGS.  1  to  4   , in some embodiments, the third part  12   c  of the insulating film layer  12  is configured to cover a border S of the binding portion  21  of the flexible printed board  2  and completely cover the integrated circuit chip  3 , and is adhered to the display module  4 . 
     The “border S of the binding portion  21  of the flexible printed board  2 ” refers to an edge of the flexible printed board  2  that overlaps the binding area  40  of the display module  4  and is consistent with an extension direction of a long edge of the binding area  40 . 
     At present, limited by the size of a customer&#39;s complete machine, the distance between borders of binding areas of a drive integrated circuit chip (Drive IC) and a main flexible printed board  2  (MFPC) is generally about 0.55 mm, which does not meet a glue spreading distance (≥0.65 mm) in a factory. Therefore, the borders of binding areas of the Drive IC and the MFPC are generally not applied with glue, so there is a risk that water vapor is likely to invade the binding areas of the Drive IC and the MFPC and causes rejects. 
     In embodiments of the application, the border S of the binding portion  21  of the flexible printed board  2  and the border of the binding area of the integrated circuit chip  3  are both covered by the insulating film layer  12  of the composite tape  1  and are packaged in an adhered manner. This can effectively avoid that water vapor invades the binding areas of the flexible printed board  2  and the integrated circuit chip  3 , thus improving the yield of the binding connection. 
     As shown in  FIGS.  1  to  3   , in some embodiments, the composite tape  1  of the application may further include a wave absorbing material layer  13 . The wave absorbing material layer  13  is located on a side of the insulating film layer  12  away from the conductive fabric layer  11 , and at the third part  12   c  of the insulating film layer  12 , and configured to cover the integrated circuit chip  3 . 
     Exemplarily, the shape of the wave absorbing material layer  13  is similar to that of the integrated circuit chip  3 , and the wave absorbing material layer  13  is configured to completely cover the integrated circuit chip  3 . 
     In some embodiments, the “shape similarity” includes cases of identical shapes and sizes, same shapes but different sizes, and roughly same shape outlines. 
     In some embodiments, the wave absorbing material refers to a type of material that can absorb or greatly weaken electromagnetic wave energy projected onto its surface to reduce electromagnetic wave interference. Exemplarily, the wave absorbing material layer in the application may be a solid powder material layer coagulated by a colloid. In some embodiments, the solid powder may be iron oxide powder or magnetic iron nano-powder. 
     The wave absorbing material layer  13  is located on the side of the insulating film layer  12  away from the conductive fabric layer  11  and covers the integrated circuit chip (Drive IC)  3 , so that electromagnetic radiation can be effectively weakened, and electromagnetic radiation from the Drive IC  3  to the outside and the interference of external electromagnetic radiation on the Drive IC  3  are reduced. 
     As shown in  FIGS.  1  to  3   , in some embodiments, the composite tape  1  of the application may further include a double-sided adhesive layer  14 . The double-sided adhesive layer  14  is located on a side of the wave absorbing material layer  13  away from the insulating film layer  12 . Edges of the double-sided adhesive layer  14  are beyond edges of the wave absorbing material layer  13  and are adhered to the insulating film layer  12 . 
     That is, the composite tape  1  of the application includes four structural layers, as shown in  FIGS.  3  and  5   , the first layer (the uppermost layer) is the conductive fabric layer  11 , the second layer is the insulating film layer  12 , the third layer is the wave absorbing material layer  13 , and the fourth layer is the double-sided adhesive layer  14 . The double-sided adhesive layer  14  and the wave absorbing material layer  13  cover the Drive IC  3 . The overall dimensions of the double-sided adhesive layer  14  are larger than the overall dimensions of the wave absorbing material layer  13 , and the part of the double-sided adhesive layer  14  beyond the wave absorbing material layer  13  is directly attached to the insulating film layer  12  to enclose the wave absorbing material layer  13 . This can prevent some powder Particles separated from the wave absorbing material layer  13  from adversely affecting the display product. In addition, one side of the double-sided adhesive layer  14  is attached to the Drive IC  3 , and the other side of the double-sided adhesive layer  14  is attached to the wave absorbing material layer  13 , so that the position of the wave absorbing material layer  13  relative to the Drive IC  3  can be fixed to prevent a reduction of a wave absorbing effect of the wave absorbing material due to a positional shift of the wave absorbing material layer  13 . 
     As shown in  FIGS.  3  and  4   , in some embodiments, the grounding portion of the flexible printed board  2  may include a first grounding portion  22  close to the binding portion  21  and a second grounding portion  23  away from the binding portion  21 . 
     Exemplarily, as shown in  FIGS.  1  to  3   , the second part  11   b  of the conductive fabric layer  11  is configured to cover the first grounding portion  22  and be adhered to the first grounding portion  22 . 
     Exemplarily, as shown in  FIGS.  1  to  3   , the conductive fabric layer  11  is configured to avoid the second grounding portion  23  of the flexible printed board  2 . 
     In other words, the conductive fabric layer  11  covers the first grounding portion  22  of the flexible printed board  2  and is electrically connected to the flexible printed board  2  through the first grounding portion  22 , and the conductive fabric layer  11  exposes the second grounding portion  23  of the flexible printed board  2 , so that the flexible printed board  2  can be grounded through the second grounding portion  23 . For example, in the case where the display module  4  for binding connection is a mobile phone module, the second grounding portion  23  of the flexible printed board  2  can be electrically connected to a middle frame of a mobile phone to achieve grounding. Thus, the flexible printed board  2  may be grounded through the conductive fabric layer  11 , and may also be grounded directly, to better ensure the circuit yield. 
     As shown in  FIGS.  1  to  3   , in some embodiments, in addition to the first part  11   a  covering the binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3 , and the second part  11   b  covering the grounding portion of the flexible printed board  2 , the conductive fabric layer  11  may further include a fourth part  11   d . The fourth part  11   d  is configured to cover the test portion of the flexible printed board  2 . 
     Further, the insulating film layer  12  includes a fifth part  12   e  located at the fourth part  11   d  of the conductive fabric layer  11  and configured to cover the test portion of the flexible printed board  2 . 
     In some embodiments, the test portion includes a plurality of test points  24  for automatic detection of a binding process section of a module production line (belonging to the front of line of the module), and as shown in  FIGS.  3  and  6   , after a module binding operation (belonging to the front of line of the module), the conductive fabric layer  11  and the insulating film layer  12  of the composite tape  1  cover the test portion (test points  24 ) of the flexible printed board  2 , and can protect the test portion, and the insulating film layer  12  under the conductive fabric layer  11  isolates the conductive fabric layer  11  from the test points  24  to prevent the test points  24  from being brought into conduction with the conductive fabric layer  11 . 
     As shown in  FIG.  4   , in some embodiments, the flexible printed board  2  is L-shaped and includes a first extension portion  201  and a second extension portion  202 , the first extension portion  201  including the binding portion  21 , the test portion (the test points  24 ) and the first grounding portion  22 , and the second extension portion  202  including the second grounding portion  23  and a component portion  25 . 
     In some embodiments, as shown in  FIG.  3   , the conductive fabric layer  11  is configured to at least cover part of the first extension portion  201  (such as covering the binding portion  21 , the test portion and the first grounding portion  22 ) and avoid the second grounding portion  23  and the component portion  25  of the second extension portion  202 , which means that the conductive fabric layer  11  does not cover the second grounding portion  23  and the component portion  25 . The insulating film layer  12  is configured to cover part of the first extension portion  201  (such as covering the binding portion  21  and the test portion). 
     In some embodiments, as shown in  FIGS.  3 , and  5  to  7   , a main body of the flexible printed board (MFPC)  2  is the thickest and generally has a 6-layer board. To ensure a space for the customer&#39;s complete machine, part of an area L of the MFPC  2  is provided with a 3-layer board. The binding portion  21  is generally provided with a 1-layer board to facilitate binding connection with the display module  4 . Specifically, an n-layer board (n is 6, 3, or 1) means that n layers of metal wiring can be provided, which can be called an ‘n-layer metal wiring board’. 
     Exemplarily, in the first extension portion  201 , the binding portion  21  includes a one-layer metal wiring board, and the edge area L on a side opposite to the binding portion  21  includes a three-layer metal wiring board to reduce the thickness of the L area, so that a battery is convenient to assemble in complete machine assembly, and a space is preserved for assembling the battery. Other areas of the first extension portion  201  include a six-layer metal wiring board. The second extension portion  202  includes a six-layer metal wiring board. 
     In a specific embodiment, using specific orientations of up, down, left, and right in  FIG.  3    as an example for description, as shown in  FIGS.  1  and  3   , the conductive fabric layer  11  is configured such that an edge of an upper side (an edge of a side away from the binding portion  21  of the flexible printed board  2 ) may be spaced from the component portion  25  of the flexible printed board  2  by a distance of approximately 4.7 mm-4.8 mm, for example about 4.772 mm, and edges of left and right sides may be spaced from borders of left and right sides of the flexible printed board  2  by a distance of approximately 1.2 mm-1.3 mm, for example about 1.256 mm. As shown in  FIG.  3   , the borders of the left and right sides of the flexible printed board  2  are borders of two ends in an extending direction of the first extension portion  201 . As shown in  FIGS.  1  and  2   , in addition to that the insulating film layer  12  has no overlap with borders of the second part  11   b  of the conductive fabric layer  11 , borders of other parts of the insulating film layer may overlap borders of the conductive fabric layer  11 . Of course, the borders of the other parts of the insulating film layer  12  may also not overlap the borders of the conductive fabric layer  11 . For example, the borders of the conductive fabric layer  11  may exceed the borders of the insulating film layer  12 . 
     As shown in  FIGS.  3  and  5  to  7   , embodiments of the present application further provide a display assembly, which includes a display module  4 , a flexible printed board  2 , an integrated circuit chip  3 , and a composite tape  1  in any of the above embodiments. 
     The binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3  are respectively in binding connection with the display module  4 . 
     The composite tape  1  is pasted on the integrated circuit chip  3  and the flexible printed board  2 . 
     As shown in  FIGS.  5  and  6   , in some embodiments, the display module  4  includes a flexible display panel  41 . The flexible display panel  41  has a binding area  40 , which is bendable to the back of the display module  4 . 
     In some embodiments, the binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3  are respectively in binding connection with the binding area  40  of the flexible display panel  41 . The composite tape  1  covers part of the binding area  40  of the flexible display panel  41  and is adhered to the part of the binding area  40 . 
     In some embodiments, the binding area  40  of the application is not only an area of the flexible display panel  41  in contact connection with the flexible printed board  2  and the integrated circuit chip  3 , and as shown in  FIG.  6   , the binding area  40  refers to the entire part of the flexible display panel  41  bent to the back of the display module  4 . 
     Exemplarily, both the conductive fabric layer  11  and the insulating film layer  12  of the composite tape  1  cover the border of the binding portion  21  of the flexible printed board  2  and completely cover the integrated circuit chip  3 , and overlap part of the binding area  40  of the display module  4 , and the insulating film layer  12  is adhered to the part of the binding area  40 . 
     As shown in  FIG.  7   , in some other embodiments, the display module  4  includes a display panel  42  and a flexible connecting board  43  with one end in binding connection with the display panel  42 . The flexible connecting board  43  has a binding area  40 . The binding area  40  is bendable to the back of the display module  4 . Exemplarily, the display panel  42  in the embodiments may be a rigid display panel. 
     In some embodiments, the binding portion  21  of the flexible printed board  2  and the integrated circuit chip  3  are respectively in binding connection with the binding area  40  of the flexible connecting board  43 . The composite tape  1  covers part of the binding area  40  of the flexible connecting board  43  and is adhered to the part of the binding area  40 . 
     Similar to the binding area of the flexible display panel in the above embodiments, as shown in  FIG.  7   , in some embodiments, the binding area  40  of the flexible connecting board  43  refers to the entire part of the flexible connecting board  43  bent to the back of the display module  4 . 
     Exemplarily, both the conductive fabric layer  11  and the insulating film layer  12  of the composite tape  1  cover the border of the binding portion  21  of the flexible printed board  2  and completely cover the integrated circuit chip  3 , and overlap part of the binding area  40  of the flexible connecting board  43 , and the insulating film layer  12  is adhered to the part of the binding area  40 . 
     In some embodiments, as shown in  FIGS.  5  to  7   , in the display assembly provided in the embodiments of the application, in addition to a display panel (for example, the flexible display panel  41  in  FIGS.  5  and  6   , or the display panel  42  in  FIG.  7   ), the display module  4  may further include structures such as a glass cover plate  44  and a polarizer  45  on a light emergent side of the display panel, and a heat dissipation module  46  (not shown in  FIG.  7   ) on the back of the display panel, which will not be described here. 
     In addition, the application further provides a display device including the display assembly in any of the above embodiments. 
     In some embodiments, the display device may be an OLED display device, and may specifically be a tablet computer, a mobile phone, or other display device. 
     It should be noted that in some embodiments of the disclosure, the display assembly and the display device may further include other structures, which may be determined according to actual requirements, and are not limited in embodiments of the disclosure. In addition, for specific application and arrangement of the composite tape provided in embodiments of the disclosure in the display assembly and the display device, reference may be made to the above description of the composite tape, which will not be repeated here. 
     Although preferred embodiments of the application have been described, additional variations and modifications of these embodiments can be made by those skilled in the art upon learning the basic inventive concept. It is therefore intended that the appended claims are interpreted as including the preferred embodiments and all such alterations and modifications that fall within the scope of the application. 
     It will be apparent to those skilled in the art that various modifications and variations can be made in embodiments of the application without departing from the spirit or scope of embodiments of the application. Thus, it is intended that the disclosure covers the modifications and variations if these modifications and variations of embodiments of the disclosure come within the claims of the disclosure and the scope of their equivalents.