JP4053315B2 - Manufacturing method of liquid crystal display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a liquid crystal display device having a glass substrate.
[0002]
[Prior art]
As a conventional method for manufacturing a liquid crystal display device, for example, there is a method disclosed in JP 820000133 of TDB (Technical Disclosure Bulletin) which is a public technical report issued by IBM Corporation of the United States. As shown in the flowchart of FIG. 9, the manufacturing method of this liquid crystal display device is roughly divided into the manufacturing steps, a glass laminating step 90, a cutting step 91, a liquid crystal injecting step 92, a polishing step 93, and a polarizing plate pasting / inspection. The process 94 is constituted.
[0003]
In the first glass bonding step 90, the glass surface that encloses the liquid crystal is treated in the orientation / rubbing step (both are treatments for adjusting the orientation of the liquid crystal), and a pair is applied in the seal coating / assembly step and the sealing step. The glass substrate is bonded to provide a space for liquid crystal (this is called a liquid crystal cell). In the cutting step 91, the vertical and horizontal dimensions of the pair of glass substrates are cut into product sizes.
[0004]
Note that the pair of glass substrates (liquid crystal cells) has a rectangular shape with a diagonal length of, for example, 14 inches used as a liquid crystal display panel of a notebook personal computer. In the case of a color liquid crystal display device, a CF ( A color filter substrate and a TFT (thin film transistor) substrate are often used on the lower side. In this case, as shown in FIG. 10, the two rectangular sides of the lower TFT substrate 2 are formed to be slightly larger (for example, several mm) than the upper CF substrate 1, and are formed to be slightly larger and protrude from the CF substrate 1. A plurality of drivers 8 (semiconductors) for driving liquid crystals are attached to the portion 21 (hereinafter referred to as a single plate portion or a frame) in the X direction and the Y direction.
[0005]
In the liquid crystal injection step 92, an annealing step (degassing impurities adhering to the inner surface of the glass substrate), a liquid crystal 3 injection step, a sealing step (sealing the liquid crystal inlet), a cleaning / annealing step, a chamfering step ( Processing of the corners of the cut glass substrate) is performed. Next, in the polishing step 93, a protective film application step for protecting the driver 8 placed on the single plate portion 21, and a thin polishing step for thinly polishing the pair of glass substrates by the polishing apparatus 150 (for example, the thickness of the liquid crystal cell). The thickness of 1.4 mm is changed to 0.8 mm), and a protective film peeling step is performed. Then, a polarizing plate (a film that transmits light that vibrates only in one direction) is attached in the polarizing plate attaching step 94, and finally the inspection step 95 is completed.
[0006]
In this conventional method for manufacturing a liquid crystal display device, the steps up to attaching to the polishing device in the polishing step 93 and the movement between the steps are performed in a state where the cell thickness before polishing is thick. There is no need to change (replacement), and there is less fear of breakage. Compared to other conventional manufacturing methods in which the polishing step is performed first (for example, the polishing step is performed before liquid crystal injection). It has become advantageous.
[0007]
[Problems to be solved by the invention]
In the conventional method for manufacturing a liquid crystal display device shown in FIGS. 9 and 10, the thickness of the single plate portion 21 is likely to vary because the polishing load escapes in the single plate portion 21 in the polishing step 93. In particular, since the polishing load easily escapes at the corner portion 22 of the single plate portion 21, there is a tendency that t1>t2> t3 and t1>t4> t5. The driver 8 is attached to the single plate portion 21, and it is necessary to connect the terminal on the TFT substrate 2 side connected to the liquid crystal and the terminal of the driver 8 at the time of attachment. As this connection method, ACF connection using an anisotropic conductive adhesive tape called ACF (Anisotropic Conductive Film) is often performed in this industry.
[0008]
However, when the thickness of the single plate portion 21 varies, it becomes difficult to apply a load at the time of ACF connection uniformly, the conductive particles in the ACF adhesive layer are not uniformly deformed, and the reliability of electrical connection is lowered. In other words, there are many cases where the ACF connection is difficult, and there is a problem that the possibility of occurrence of a failure in the connection of the driver 8 increases.
[0009]
The present invention has been made in consideration of such problems, and the thickness of the single plate portion of the glass substrate on which the driver for driving the liquid crystal is mounted can be made constant without variation, and the driver for driving the liquid crystal It is a main object to provide a method for manufacturing a liquid crystal display device that can be securely connected.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, the method for manufacturing a liquid crystal display device according to the present invention employs the following means.
[0011]
That is, as described in claim 1, a method of manufacturing a liquid crystal display apparatus for polishing the liquid crystal cell after processing the horizontal and vertical dimensions of the liquid crystal cell having a pair of large and small glass substrates to product size thin, the A large glass substrate in the liquid crystal cell is provided with a single plate portion that protrudes from the small glass substrate and a driver for driving the liquid crystal is mounted , and the single plate portion is evenly polished on the small glass substrate side surface of the single plate portion. A liquid crystal cell is polished by disposing a spacer member to act on the liquid crystal.
[0012]
In this means, a spacer member is provided on one glass substrate of a liquid crystal cell processed into a product size and polished together with the glass substrate, and the polishing load is transmitted to one glass substrate through the spacer member.
[0013]
In the present invention, the single plate portion is provided in a portion including a corner portion of the liquid crystal cell, and the spacer member is provided in a portion corresponding to the corner portion of the liquid crystal cell in the single plate portion .
[0014]
In this means, the spacer member is provided at the corner of the liquid crystal cell where the polishing load is most likely to escape.
[0015]
Furthermore, in the present invention, the thickness of the spacer member can be made substantially equal to the thickness of the small glass substrate.
[0016]
With this means, a polishing load having the same magnitude as the polishing load at other locations is transmitted to one glass substrate through the spacer member, and the spacer member is polished in the same manner as the glass substrate without the spacer member. The
[0017]
In the present invention, the spacer member is preferably made of the same material as the small glass substrate or a material having the same polishing characteristics.
[0018]
By this means, the spacer member is polished at the same speed as the glass substrate.
[0019]
In this invention, a spacer member shall be attached to the said single-plate part with a double-sided tape or an adhesive agent.
[0020]
In this means, the spacer member is fixed to the glass substrate, and the mounting position is stabilized in the polishing process.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a mode of a method for manufacturing a liquid crystal display device according to the present invention will be described with reference to the drawings.
[0022]
FIGS. 1-5 shows Embodiment (1) of the manufacturing method of the liquid crystal display device based on this invention.
[0023]
In this embodiment, a manufacturing method is mainly shown for the polishing step after the pair of glass substrates 1 and 2 are bonded together, the vertical and horizontal dimensions are processed into the product size, and the liquid crystal 3 is sealed.
[0024]
In the manufacturing method of the liquid crystal display device of this embodiment, the double-side polishing apparatus 100 is used. The double-side polishing apparatus 100 includes an upper surface plate 101, an upper surface plate driving shaft 102, a lower surface plate 111, a lower surface plate driving shaft 112, a support table for a lower surface plate (not shown), and a vertical movement mechanism for the upper surface plate. And a load applying device. Then, the upper surface plate 101 and the lower surface plate 110 rotate in the opposite directions, and the object to be processed sandwiched therebetween, here, the liquid crystal cell 10 is polished. Usually, a large planetary gear mechanism is provided on the lower surface plate 110, and a type in which a plurality of workpieces are placed on the carrier of the planetary gear mechanism is often used.
[0025]
The liquid crystal cell 10 includes a pair of glass substrates 1 and 2, a CF substrate 1 that is an upper glass substrate constituting a color liquid crystal display device, and a TFT that is a lower glass substrate slightly larger than the CF substrate 1. It consists of a substrate 2, a liquid crystal 3 injected in a slight gap (about several microns) provided between these substrates, and a seal 4 that seals the liquid crystal 3 and bonds the substrates together.
[0026]
A plurality of drivers 8 for driving the liquid crystal are attached to the single plate portion 21 of the TFT substrate 2 protruding from the CF substrate 1 in the X and Y directions.
[0027]
And the spacer member 5 for grinding | polishing is provided in the corner | angular part 22 of this single plate part 21. As shown in FIG. The spacer member 5 is an L-shaped block member in plan view having a side having a length L1 and a width L2 in the X direction and a side having a length L3 and a width L4 in the Y direction, and the spacer member 5 is not provided. It has a thickness ts substantially equal to the thickness tcf of the CF substrate 1 which is a glass substrate. It should be noted that the lengths L1 and L3 are in a range that does not reach the driver 8, and the widths L2 and L4 may be any length that is at least half the widths A and B of the single plate portion 21. The spacer member 5 is attached to the single plate portion 21 of the TFT substrate 2 with a double-sided tape or an adhesive.
[0028]
The material of the spacer member 5 is preferably the same material as that of the glass substrate 1 or 2, but a material having polishing characteristics (speed at which polishing is performed) similar to that of the glass material used for the glass substrate 1 or 2, for example, other materials Any kind of glass material, glass fiber impregnated epoxy material, metal (stainless steel, aluminum material), etc. may be used.
[0029]
A method of manufacturing the liquid crystal display device having the above configuration will be described below.
[0030]
The pair of glass substrates 1 and 2 are bonded together (step 90), the vertical and horizontal dimensions are cut into a product size (step 91), and the liquid crystal is sealed (step 92). The liquid crystal cell 10 proceeds to the polishing step 11. .
[0031]
In the polishing step 11, first, in the protective film application step 12, a protective film is applied from above the driver 8 so that the driver 8 does not malfunction with the polishing liquid or the like. Then, the spacer member 5 is attached to the corner portion 22 of the single plate portion 21 of the TFT substrate 2 (spacer member attachment step 13), and a protective film is formed between the upper surface plate 101 and the lower surface plate 111 of the double-side polishing apparatus 100. The coated liquid crystal cell 10 is set, and a polishing liquid containing an abrasive is poured into the double-side polishing apparatus 100.
[0032]
The lower surface 23 of the liquid crystal cell 10 is supported by the upper surface 113 of the lower surface plate 111, and the upper surface 24 of the liquid crystal cell 10 is pressed against the lower surface 103 of the upper surface plate 101 while pressing the spacer member 5 with the lower surface 103 of the upper surface plate 101. Since the upper surface plate 101 and the lower surface plate 110 rotate in opposite directions, the upper and lower surfaces 23 and 24 of the liquid crystal cell 10 are polished and thinned.
[0033]
At this time, the load of the upper surface plate 101 acts uniformly on the portion where the CF substrate 1 and the TFT substrate 2 overlap with each other, and the spacer is also applied to the corner portion 22 of the single plate portion 21 of the TFT substrate 2. The load of the upper surface plate 101 acts through the member 5. Here, the protruding lengths A and B of the single plate portion 21 are about 2 mm, and are generally as small as about 1/100 compared to the vertical and horizontal dimensions of the liquid crystal cell 10, so that the corner portion 22 (X and Y directions overlap) It is possible to apply the load of the upper surface plate 101 almost uniformly on the entire single plate portion 21 only by providing the spacer member 5 at a place where the load escape is considered to be the largest. As a result, it is possible to almost eliminate variations in the thickness of the single plate portion 21 in the X direction and the Y direction (thickness variations in t1 to t7 in FIG. 5 in the X direction).
[0034]
Thereby, since the thickness of the single plate portion 21 is not varied, the load of the ACF connection is evenly applied in the mounted state of the drivers 81 to 87, and the conductive particles in the ACF adhesive layer are uniformly deformed, so that the electric connection Increased reliability. That is, the ACF connection is surely performed, and there is no possibility that a failure occurs in the connection of the driver 8.
[0035]
When the thickness tc (= CF substrate thickness tcf + TFT substrate thickness ttf) of the liquid crystal cell 10 is reduced to the target thickness in the polishing step 11, the spacer member 5 is removed in the spacer member removal step 15. Then, the protective film that was protecting the driver 8 in the protective film peeling step 16 is peeled off, the polarizing plate is stuck in the polarizing plate sticking step 94, and the inspection process 95 is completed.
[0036]
According to this embodiment, the spacer member 5 is provided on one glass substrate 2 of the liquid crystal cell 10 processed to the product size and polished together with the glass substrate 1, and the polishing load is passed through the spacer member 5 to one side. Since it is transmitted to the glass substrate 2, the thickness of the single plate portion 21 of the glass substrate 2 to which the driver 8 for driving the liquid crystal is attached can be made constant without variation.
[0037]
Further, since the spacer member 5 is provided at the corner portion 22 of the liquid crystal cell 10 where the polishing load is most easily escaped, the thickness of the single plate portion 21 of the glass substrate 2 can be made uniform only by providing the small spacer member 5. Can be constant.
[0038]
In this embodiment, the double-side polishing apparatus 100 is used. However, the present invention is not limited to this, and it is possible to perform single-side polishing using a single-side polishing apparatus (not shown).
[0039]
Further, although the liquid crystal cell 10 is a color liquid crystal display device, it is naturally applicable to a monochrome liquid crystal display device.
[0040]
FIG. 6 shows an embodiment (2) of a method for manufacturing a liquid crystal display device according to the present invention.
[0041]
In this liquid crystal display manufacturing method, the shape of the spacer member 5 is changed with respect to the embodiment (1). Others are the same.
[0042]
The spacer member 5 is a rectangular parallelepiped L-shaped block material of the embodiment (1), and is attached to the corner portion 22 of the single plate portion 21 of the TFT substrate 2 as in the embodiment (1). It is. The width L <b> 1 and the length L <b> 2 of the spacer member 5 need only cover the corner portion 22. Thus, even by providing a rectangular parallelepiped spacer, variation in the thickness of the single plate portion 21 can be eliminated almost as in the embodiment (1).
[0043]
According to this embodiment, substantially the same operations and effects as the above-described embodiment (1) are exhibited.
[0044]
FIG. 7 shows an embodiment (3) of a method for manufacturing a liquid crystal display device according to the present invention.
[0045]
In this liquid crystal display manufacturing method, the shape of the spacer member 5 is changed with respect to the embodiment (1). Others are the same.
[0046]
This spacer member 5 extends two sides (lengths L 1 and L 3) of the L-shaped block member of the embodiment (1) over almost the entire single plate portion 21. Note that the widths L3 and L4 of these two sides may be at least half the width of the single plate portion 21. As a result, the load of the upper platen 101 can be applied to the single plate portion 21 almost completely, and the thickness variation of the single plate portion 21 can be further eliminated. Further, although the spacer member 5 has the driver 8 underneath, there is no fear of causing a problem to the driver 8 even if the load of the upper surface plate 101 is applied in normal polishing.
[0047]
According to this embodiment, the same operations and effects as those of the above-described embodiment (1) can be achieved.
[0048]
The spacer member 5 is not limited to the shape shown in each of the above-described embodiments. For example, the spacer member 5 may have a circular shape. For example, a plurality of spacer members 5 may be attached while avoiding the corners 22. However, a predetermined effect can be obtained.
[0049]
【Example】
Polishing is performed when the spacer member 5 is not provided (conventional polishing step 93) and when the spacer member 5 is provided (polishing step 11), and variations in the thickness of the single plate portion 21 of the TFT substrate 2 are observed in the X direction and the Y direction. Compared.
The dimensions of the liquid crystal cell 10 and the like are 254 mm in width, 191.9 mm in length, the thickness of the CF substrate is 0.7 mm (initial), the thickness of the TFT substrate is 0.7 mm (initial), and the width A of the single plate portion 21. B = 2 mm, spacer member 5 size: L1 = 5 mm, L3 = 15 mm, L2 = L4 = 2 mm, and spacer member 5 thickness 0.7 mm (initial). Then, the thickness of the liquid crystal cell was reduced to 0.8 mm (0.4 mm on one side) by polishing.
Further, in the X direction, as shown in FIG. 5, in the X direction, the position of the driver 81 is X1, the position of the driver 82 is X2,..., And the position of the driver 87 is X7 in order from the corner 22 of the single plate portion 21. age,
The difference in thickness of the single plate portion 21 was measured by the difference in thickness at the positions on both sides of each driver 81 to 87 as (t1-t2), (t2-t3). Moreover, the position Y1 to the position Y3 was also measured with a difference in the Y direction.
[0050]
The result is shown in FIG. As is apparent from this figure, in the X direction, it can be seen that the thickness difference is greatly reduced as indicated by C at the position X1 closest to the corner portion 22 of the single plate portion 21. In the Y direction, it can be seen that the difference in thickness is greatly reduced as indicated by D at the position Y1 closest to the corner portion 22 of the single plate portion 21. Thus, it can be seen that by providing the spacer member 5 at the corner portion 22 of the single plate portion 21, variation in the thickness of the single plate portion 21 can be greatly reduced.
[0051]
【The invention's effect】
As described above, in the method for manufacturing a liquid crystal display device according to the present invention, a spacer member is provided on one glass substrate of a liquid crystal cell processed into a product size and polished together with the glass substrate. Therefore, the thickness of the single plate portion of the glass substrate to which the driver for driving the liquid crystal is attached can be made constant without variation. Accordingly, there is an effect that it is possible to reliably connect a driver for driving the liquid crystal.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment (1) of a method for manufacturing a liquid crystal display device according to the present invention.
FIG. 2 is a cross-sectional view taken along the line U-U in FIG. 1, and the upper left diagram is a partially enlarged view.
FIG. 3 is a flowchart showing an embodiment (1) of a method for manufacturing a liquid crystal display device according to the present invention.
FIG. 4 is a perspective view of main components showing an embodiment (1) of a method for manufacturing a liquid crystal display device according to the present invention.
FIG. 5 is a view taken in the direction of arrow V in FIG.
FIG. 6 is a perspective view of main parts showing an embodiment (2) of a method for manufacturing a liquid crystal display device according to the present invention.
FIG. 7 is a perspective view of main parts showing an embodiment (3) of a method for manufacturing a liquid crystal display device according to the present invention.
FIG. 8 is a graph showing an effect of an embodiment of a manufacturing method of a liquid crystal display device according to the present invention.
FIG. 9 is a flowchart showing a method for manufacturing a conventional liquid crystal display device.
10A and 10B are diagrams illustrating a conventional method for manufacturing a liquid crystal display device, in which FIG. 10A is a front sectional view, and FIG.
[Explanation of symbols]
1 Glass substrate (CF substrate)
2 Glass substrate (TFT substrate)
3 Liquid crystal 4 Seal 5 Spacer member 8 Driver 10 Liquid crystal cell 11 Polishing process 12 Protective film coating process 13 Spacer member attaching process 14 Thin polishing process 15 Protective film peeling process 21 Single plate part 22 Corner part 23 Lower surface 24 Upper surface 81 87 Driver 90 Glass bonding process 91 Cutting process 92 Liquid crystal injection process 93 Polishing process 94 Polarizing plate attaching / inspecting process 100 Double-side polishing apparatus 101 Upper surface plate 102 Upper surface plate driving shaft 103 Lower surface 111 Lower surface plate 112 Lower surface plate driving shaft 113 Upper surface

Claims (5)

The liquid crystal cell after processing the horizontal and vertical dimensions of the liquid crystal cell having a pair of large and small glass substrates to product size method of manufacturing the liquid crystal display apparatus for polishing thin,
A large glass substrate in the liquid crystal cell is provided with a single plate portion that protrudes from the small glass substrate and a driver for driving the liquid crystal is mounted, and a polishing load is applied to the surface of the single plate portion on the small glass substrate side. A method of manufacturing a liquid crystal display device, characterized in that a liquid crystal cell is polished by providing a spacer member for evenly acting . 2. The method of manufacturing a liquid crystal display device according to claim 1, wherein the single plate portion is provided in a portion including a corner portion of the liquid crystal cell, and the spacer member corresponds to a corner portion of the liquid crystal cell in the single plate portion. A method for manufacturing a liquid crystal display device, comprising: 3. The method for manufacturing a liquid crystal display device according to claim 1, wherein the spacer member has a thickness substantially equal to that of the small glass substrate . 4. The method of manufacturing a liquid crystal display device according to claim 1, wherein the spacer member is made of the same material as a small glass substrate or a material having equivalent polishing characteristics. . 5. The method of manufacturing a liquid crystal display device according to claim 1, wherein the spacer member is attached to the single plate portion with a double-sided tape or an adhesive.

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