JP2008185978A - Liquid crystal module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal module the reliability of which is enhanced by preventing the peeling-off of an end of a COF film out of a printed wiring board or a liquid crystal display panel, without causing increase of production costs due to increase of assembly man-hours, material costs, parts count, or the like. <P>SOLUTION: The liquid crystal module is composed such that a rectangular opening 11g is formed between one end edge 11e of the film 11c of the COF 11 and the part of mounting a driver IC chip 11d, and/or between the other end edge 11f of the film 11c and the part of mounting the driver IC chip 11d, and then one end edge 11e of the film is crimped to a printed wiring board 10 and also the other end edge 11f of the film is crimped to the end of the liquid crystal display panel 8. The rigidity of the COF film 11c is lowered by the opening 11g, which increases the flexibility and reduce the distortion stress thereof, and a large distortion stress does not act on both end edges 11e, 11f of the crimped film 11c, thereby preventing the peeling-off of the both end edges. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal module incorporated in a television or the like, and more particularly, to an improved liquid crystal module so that the end of a COF (chip on film) film does not peel from a liquid crystal display panel or a printed wiring board.

  A conventional general liquid crystal module incorporated in a television or the like includes a reflection sheet, a light source for backlight, a light diffusion plate, a light diffusion sheet, a liquid crystal display panel, etc., stacked and accommodated in a frame, and a liquid crystal with a bezel from above. It has a structure in which the peripheral edge of the display panel is pressed and fixed, and a COF is disposed between the liquid crystal display panel and a printed wiring board in the vicinity thereof, and both ends of the film are disposed between the liquid crystal display panel and the printed wiring board. It is crimped to.

  The above-mentioned COF (chip on film) is obtained by mounting a driver IC chip on a flexible insulating film in which an input side lead pattern and an output side lead pattern are formed. One end edge of the film in which the terminal portions of the film are parallel is thermocompression bonded to the end portion of the printed wiring board via a heat-sensitive adhesive, and the other end edge of the film in which the terminal portions of the lead pattern on the output side are in parallel is The liquid crystal display panel is thermocompression bonded to the end of the liquid crystal display panel via a heat sensitive adhesive.

  However, when both ends of the COF film are bonded to the printed wiring board and the liquid crystal display panel by thermocompression bonding as described above, it is difficult to obtain a large bonding strength, and the COF film is flexible. Because it has a certain degree of rigidity, for example, when the COF film is repeatedly distorted due to thermal expansion and contraction of the frame or the like, there is a possibility that the thermocompression-bonded end of the film may be peeled off due to the distortion stress. .

  By the way, as a liquid crystal display device for preventing COF peeling, one end side (input side) of the COF film is thermocompression bonded to the printed wiring board, and the other end side (output side) of the COF film is a liquid crystal display panel. A film is known in which two places on one end side or two places on the other end side of this film are further bonded and fixed with an adhesive (Patent Document 1).

  As another liquid crystal display device for the purpose of preventing COF peeling, the size of the printed wiring board is increased and the end of the printed wiring board is adhered and fixed to the end of the liquid crystal display panel with a double-sided adhesive tape. Also known is one in which distortion or the like is less likely to occur in the COF (Patent Document 2).

Then, as a COF type semiconductor device, a semiconductor element is joined and mounted on a conductor lead of a film base via a protruding electrode, and the semiconductor element is mounted on the film base (in a region between the tip portions of the conductor lead). The thing which provided the cut | interruption is also known (patent document 3).
Japanese Patent Laid-Open No. 2-96795 Japanese Patent Laid-Open No. 1-237685 JP 2002-208612 A

  However, as in the liquid crystal display device of Patent Document 1, if the two places on one end side of the COF film or the two places on the other end side are further bonded and fixed with an adhesive, the film is difficult to peel off. In addition, since it is necessary to add a process of bonding and fixing with an adhesive, there is a problem that the manufacturing cost increases due to an increase in the number of assembly steps and material costs. In addition, when the end portion of the printed wiring board having a large size is attached and fixed to the end portion of the liquid crystal display panel with a double-sided adhesive tape as in the liquid crystal display device of Patent Document 2, assembly man-hours, material cost, number of parts, etc. There is a problem that the manufacturing cost is increased due to the increase in the number of.

  In addition, as in the case of the COF type semiconductor device of Patent Document 3, a semiconductor substrate where a semiconductor element is mounted on the film base (in the region between the tip portions of the conductor leads) is applied to the protruding electrode by thermal contraction. Although it is possible to prevent cracking of the protective layer on the semiconductor element caused by the applied stress, it is difficult to increase the flexibility of the film substrate and reduce the strain stress. Therefore, the COF in which the technology of Patent Document 3 is diverted and the driver IC chip mounting portion of the film is cut is used in a conventional liquid crystal module, and both ends of the film are bonded to a printed wiring board and a liquid crystal display panel. However, since a relatively large strain stress generated in the film acts on both ends of the film that are pressure-bonded, it is not possible to sufficiently prevent the film from being peeled off at both ends.

  The present invention has been made under the above circumstances, and the problem to be solved is the end of the COF film without causing an increase in manufacturing cost due to an increase in assembly man-hours, material costs, number of parts, etc. Is to provide a liquid crystal module that is prevented from peeling off from a printed wiring board or a liquid crystal display panel to enhance reliability.

  In order to solve the above-described problems, a liquid crystal module according to the present invention includes a printed circuit board and a liquid crystal display panel including a COF formed by mounting a driver IC chip on a film formed with an input side lead pattern and an output side lead pattern. And the other end edge of the film in which the terminal portion of the lead pattern on the output side is arranged in parallel to the end portion of the printed wiring board. And a liquid crystal module each crimped to the end of the liquid crystal display panel, between the one end edge of the film and the driver IC chip mounting location and / or between the other end edge of the film and the driver IC chip mounting location. , An opening is formed.

  In the liquid crystal module of the present invention, it is preferable that the opening is a rectangular opening and is formed in parallel with one edge and / or the other edge of the film.

  A more specific preferable liquid crystal module according to the present invention includes a COF in which a driver IC chip is mounted on a film on which an input side lead pattern and an output side lead pattern are formed, between a printed wiring board and a liquid crystal display panel. One end edge of the film arranged between the terminal portions of the input-side lead pattern and the other end edge of the film where the terminal portions of the output-side lead pattern are arranged in parallel with the end portion of the printed wiring board and the liquid crystal In the liquid crystal modules each crimped to the end of the display panel, between the one end edge of the film and the driver IC chip mounting portion and / or between the other end edge of the film and the driver IC chip mounting portion, When a rectangular opening having substantially the same length as the driver IC chip is formed in parallel with one edge and / or the other edge of the film, To, and is characterized in that the rounded for preventing cleavage at both ends of the opening.

  As in the liquid crystal module of the present invention, an opening is formed between one end edge of the COF film and the driver IC chip mounting portion and / or between the other end edge of the COF film and the driver IC chip mounting portion. If this is done, the opening will reduce the rigidity of the film, increase the flexibility, reduce the strain stress generated in the film, and the large strain stress will not act on both edges of the film that has been crimped. Both end edges are difficult to peel off from the printed wiring board or the liquid crystal display panel, and the reliability is improved. In addition, the liquid crystal module of the present invention, like the liquid crystal display devices of Patent Documents 1 and 2, is further reinforced by bonding the edges of the film with an adhesive, or the printed wiring board and the liquid crystal display panel are bonded with double-sided adhesive tape Since there is no need to stick and fix, it is only necessary to crimp both ends of the COF film to the printed wiring board and the liquid crystal display panel as in the conventional case, increasing the manufacturing cost by increasing the number of assembly steps, material costs, parts count, etc. This is advantageous in terms of manufacturing and economy.

  In addition, the liquid crystal module in which the opening is formed as a rectangular opening and is formed in parallel with one end edge and / or the other end edge of the film has, for example, one end edge and Since the opening dimension in the direction parallel to the other end edge can be taken long, the strain stress of the film can be further reduced and the peeling prevention effect can be enhanced.

  Further, as in a more specific preferred liquid crystal module, a rectangular opening having substantially the same length as the driver IC chip is formed in parallel with one end edge and / or the other end edge of the film, and the opening If both ends of the film are rounded to prevent tearing, the distortion stress of the film can be sufficiently reduced and a good peeling prevention effect can be obtained without causing much trouble in the formation of the lead pattern on the input side and / or the output side. Moreover, since the film can be prevented from tearing from both ends of the opening by the roundness for preventing the tear, the reliability is further improved.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an exploded perspective view of a liquid crystal module according to an embodiment of the present invention, and FIG. 2 is a plan view of a main part of the liquid crystal module with a conductive pattern formed on a COF film omitted. 3 is a cross-sectional view taken along the line AA of FIG. 2, FIG. 4 is a plan view of a COF used in the liquid crystal module, and FIG. 5 is a plan view showing another example of the COF.

  The liquid crystal module shown in FIG. 1 is incorporated in a television, and a rectangular light reflecting sheet 3 is superimposed on a lower part of a rectangular frame 1 via a strip-shaped rubber spacer 2 arranged along four sides. On top of this, a large number of cold-cathode tubes 4 are arranged in parallel as linear light sources. A rectangular light diffusion plate 5, a lower light diffusion sheet 6 a, an embossing film 7, an upper light diffusion sheet 6 b, and a liquid crystal display panel 8 are sequentially stacked on the upper side of the cold cathode fluorescent lamp 4. The four peripheral portions of the liquid crystal display panel 8 are pressed by the bezels 9a and 9b from above, and the above components are fixed so as not to be detached from the frame 1.

  In the vicinity of one long side of the liquid crystal display panel 8, two strip-like printed wiring boards 10, 10 are arranged, and these printed wiring boards 10, 10 and end portions (long sides of the liquid crystal display panel 8). Part) is connected through several COFs 11. In addition, a strip-shaped printed wiring board 12 is also arranged near one short side of the liquid crystal display panel 8, and the printed wiring board 10 and an end portion (short side portion) of the liquid crystal display panel are several COFs 13. It is connected through. These printed wiring boards 10, 10, and 12 are attached to the side surfaces of the frame 1 with the cushion material 14 sandwiched while the COFs 11 and 13 are bent 90 ° downward.

  As shown in FIG. 4, the COF 11 has a flexible insulating film 11c on which a lead pattern 11a on the input side (printed wiring board side) and a lead pattern 11b on the output side (liquid crystal display panel side) are formed. (Source Driver) An IC chip 11d is mounted, and as shown in FIGS. 2 and 3, one end edge 11e where the lead pattern terminals on the input side of the film 11c are arranged in parallel is on the output side of the printed circuit board 10. The other end edge 11f in which the terminals of the lead pattern on the output side of the film 11c are arranged in parallel is thermo-compressed to the end portion where the terminal is formed via a heat-sensitive adhesive (not shown). These terminals are thermocompression-bonded via a heat-sensitive adhesive (not shown) to the end where the terminals are formed. Between the other end edge 11f of the film 11c and the driver IC chip mounting portion, a rectangular opening 11g having substantially the same length as the driver IC chip 11d is parallel to the other end edge 11f of the film 11c. The opening 11g is provided with roundness 11h for preventing cracks at the corners at both ends of the opening 11g. Since the opening 11g is formed in this way, the output-side lead pattern 11b has a pattern shape that bypasses the opening 11g as shown in FIG.

  Said opening part 11g weakens the rigidity of the film 11c of COF11, increases flexibility, reduces the distortion stress generated in the film 11c, and both ends of the film 11c thermocompression bonded to the printed wiring board 10 and the liquid crystal display panel 8 The edge 11e, 11f is formed so as to prevent a large strain stress from acting on the edges 11e, 11f of the film 11c, and is formed to prevent the peeling of the edges 11e, 11f of the film 11c. If formed in parallel with the other end edge 11f of 11c, for example, the opening dimension in the direction parallel to the one end edge 11f can be made longer than in the case of forming a circular opening, for example, the distortion of the film 11c. The action of reducing the stress is increased. In particular, when the length of the opening 11g is substantially the same as that of the driver IC chip 11d as in this embodiment, the output Also no worry that causes problems in the formation of the lead pattern 11b. And, since the film 11c can be prevented from tearing from both ends of the opening 11g when the above-mentioned tear prevention roundness (R) 11h is attached to the corners at both ends of the opening 11g, the reliability is improved. It is further enhanced.

  Such an opening 11g may be formed between the one end edge 11e of the film 11c and the driver IC chip mounting portion, or between the one end edge 11e of the film 11c and the driver IC chip mounting portion, and the film. You may form in both between the other end edge 11f of 11c, and a driver IC chip mounting location. In particular, when the film 11c is formed on both sides, the flexibility of the film 11c is further increased, and the strain stress is greatly reduced. Therefore, the effect of preventing the peeling of the both end edges 11e and 11f of the film 11c becomes remarkable. Further, the opening 11g formed in the film 11c may be formed in a narrow rectangular shape (in other words, a slit shape) as shown in FIG. 5, and rounds 11h for preventing cleavage at both ends are formed in a circular shape. May be.

  The COF 11 shown in FIG. 5 has the same configuration as the COF 11 shown in FIG. 4 except that the shape of the opening 11g and the roundness 11h is slightly different as described above. The description is omitted.

  The COF 13 for connecting one short side of the liquid crystal display panel 8 and the printed wiring board 12 in the vicinity thereof is formed on the above-mentioned COF 11 on a flexible insulating film in which an input side lead pattern and an output side lead pattern are formed. The gate driver IC chip is mounted in place of the source driver IC chip 11d, and one end edge of the film input side terminals in parallel is at the end of the printed wiring board 12 where the output side terminals are formed. The other end edge where the terminals on the output side of the film are parallel is thermocompression bonded via a heat sensitive adhesive, and the end of the liquid crystal display panel 8 where the scanning line terminals are formed is thermocompression bonded via a heat sensitive adhesive. Has been.

  In the liquid crystal module configured as described above, the rigidity of the film 11c is weakened by the rectangular opening 11g formed in the film 11c of the COFs 11 and 13, the flexibility is increased, and the strain stress generated in the film 11c is reduced. Therefore, for example, even if the film 11c of the COFs 11 and 13 is repeatedly distorted due to thermal expansion and contraction of the frame 1 or the like, a large strain stress does not act on both end edges 11e and 11f of the film 11c that has been pressed. Therefore, both end edges 11e and 11f of the film 11c of the COFs 11 and 13 are difficult to peel off from the printed wiring boards 10 and 12 and the liquid crystal display panel, and the film 11c is formed by rounds 11h for preventing tearing at both ends of the opening 11g. Since there is no risk of tearing from both ends of the opening 11g, the reliability is greatly improved. In addition, this liquid crystal module is reinforced by adhering the edges of the film with an adhesive, as in the liquid crystal display devices of Patent Documents 1 and 2, and the printed wiring board and the liquid crystal display panel are attached with a double-sided adhesive tape. There is no need for fixing, and both end edges 11e and 11f of the film 11c of the COFs 11 and 13 need only be pressure-bonded to the printed wiring boards 10 and 12 and the liquid crystal display panel 8 as in the prior art. This is advantageous in terms of production and economy, without causing a concern of an increase in production cost due to such an increase.

It is a disassembled perspective view of the liquid crystal module which concerns on one Embodiment of this invention. It is a principal part top view of the liquid crystal module, Comprising: The conductive pattern formed in the film of COF is abbreviate | omitted and shown. It is the sectional view on the AA line of FIG. It is a top view of COF used for the liquid crystal module. It is a top view which shows the other example of COF.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Frame 3 Light reflection sheet 4 Cold cathode tube 5 Light diffusion plate 6a, 6b Light diffusion sheet 7 Emboss film 8 Liquid crystal display panel 9a, 9b Bezel 10, 12 Printed wiring board 11, 13 COF
11a Input side lead pattern 11b Output side lead pattern 11c Film 11d Driver IC chip (source driver IC chip)
11e One end edge of the film 11f Other end edge of the film 11g Opening portion 11h Roundness for preventing tearing

Claims (3)

A COF in which a driver IC chip is mounted on a film on which an input side lead pattern and an output side lead pattern are formed is disposed between a printed wiring board and a liquid crystal display panel. In the liquid crystal module in which one end edge of the film in parallel and the other end edge of the film in which the terminal portion of the lead pattern on the output side is in parallel are crimped to the end of the printed wiring board and the end of the liquid crystal display panel, respectively.
A rectangular shape having substantially the same length as the driver IC chip between one end edge of the film and the driver IC chip mounting portion and / or between the other end edge of the film and the driver IC chip mounting portion. An opening is formed in parallel with one end edge and / or the other end edge of the film, and the opening is rounded at both ends to prevent cleavage. A COF in which a driver IC chip is mounted on a film on which an input side lead pattern and an output side lead pattern are formed is disposed between a printed wiring board and a liquid crystal display panel. In the liquid crystal module in which one end edge of the film in parallel and the other end edge of the film in which the terminal portion of the lead pattern on the output side is in parallel are crimped to the end of the printed wiring board and the end of the liquid crystal display panel, respectively.
A liquid crystal module, wherein an opening is formed between one end edge of the film and a driver IC chip mounting portion and / or between the other end edge of the film and a driver IC chip mounting portion.   The liquid crystal module according to claim 2, wherein the opening is a rectangular opening and is formed in parallel with one end edge and / or the other end edge of the film.

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