JP2003005208A - Lamination method for liquid crystal display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent pollution in the electrode terminal part of a liquid crystal display panel and to prevent bubbles from remaining in each liquid crystal display panel gap. SOLUTION: A first liquid crystal display panel is so placed that electrode terminals of a pair of transparent substrates 2 constituting the first liquid crystal display panel 1 may be turned up, and four panel sealant parts 7 which have a high viscosity and have a length L longer than a length L' of an electrode terminal part 4 which is an electrode terminal formation area placed in a position corresponding to a sealant 3 for transparent substrates for adhesion between the pair of transparent substrates 2 on the upper face of the first liquid crystal display panel 1 are formed in side edge parts of respective sides on the upper face of the first liquid crystal display panel 1, and an adhesive 11 having a low viscosity is dropped on the center part of the upper face of the first liquid crystal display panel 1, and a second liquid crystal display panel 9 is arranged on the first liquid crystal display panel 1, and a press-fitting jig 13 is lowered onto the center part of the second liquid crystal display panel 9 to apply a pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel laminating method for laminating two or more liquid crystal display panels.

[0002]

2. Description of the Related Art Generally, a liquid crystal display device for displaying information such as a specific figure or character is often used as a display device for a computer, a mobile phone or the like. A liquid crystal display panel for displaying information such as specific figures and characters by selectively applying a voltage is built in a predetermined portion of a pair of filled transparent substrates.
As the liquid crystal used in this liquid crystal display panel, a cholesteric phase including a nematic phase, a smectic phase, and a chiral nematic phase in which a chiral agent is added to the nematic phase is used.

In some cases, a plurality of the liquid crystal display panels are stacked and used in the liquid crystal display device for the reason that a peculiar display is possible. For example, by stacking multiple liquid crystal display panels each filled with a cholesteric phase whose chiral pitch is adjusted to selectively reflect light in different wavelength regions, light is selectively reflected by the chiral pitch of each cholesteric phase. hand,
Multicolor information can be displayed by displaying light reflected by each liquid crystal display panel or by combining light reflected by a plurality of liquid crystal display panels.

As an adhesive means for adhering a plurality of these laminated liquid crystal display panels, an adhesive can be easily applied to the liquid crystal display panel by screen printing or the like, and air bubbles in the gaps between the liquid crystal display panels are prevented from remaining. Liquid adhesives have been used more often than before because, for example, the positions of the liquid crystal display panels can be changed after the liquid crystal display panels are bonded.

[0005]

However, when a plurality of liquid crystal display panels are bonded with a liquid adhesive, the adhesive flows to the electrode terminal portions of the liquid crystal display panel. In some cases, the electrode terminals of the liquid crystal display panel were contaminated. In this case, in electrically connecting the printed circuit board for driving the liquid crystal display panel and the liquid crystal display panel via the flexible wiring board, the electrode terminals of the liquid crystal display panel and the lead terminals of the flexible wiring board are connected. Could not be securely connected.

Further, even when a liquid adhesive is used, there is a problem that a good display cannot be performed because a small amount of bubbles are generated between the liquid crystal display panels. .

On the other hand, in order to prevent the generation of a small amount of bubbles, a method of reducing the viscosity of the adhesive may be considered. However, if the viscosity of the adhesive is reduced, the fluidity of the adhesive increases, so that the adhesive flows to the electrode terminal portion and contaminates the electrode terminal portion. Therefore, the above problems cannot be solved only by decreasing the viscosity of the adhesive.

The present invention has been made in view of these points, and prevents contamination of electrode terminal portions of a liquid crystal display panel,
Another object of the present invention is to provide a method for laminating liquid crystal display panels, which can prevent air bubbles from remaining in the gaps between the liquid crystal display panels.

[0009]

In order to achieve the above object, a method for laminating a liquid crystal display panel according to the invention as defined in claim 1 is such that one transparent substrate among a pair of transparent substrates constituting the liquid crystal display panel is used. The liquid crystal display panel is mounted so that a plurality of aligned electrode terminal portions face upward, and the upper surface of the other transparent substrate constituting the liquid crystal display panel, at least the side on which the electrode terminals are formed. After forming a highly viscous panel sealant having a length dimension longer than the length dimension of the electrode terminal portion, which is the formation region of the plurality of aligned electrode terminals, on the side edge portion of the liquid crystal display. Attach a low-viscosity adhesive to the center of the top of the panel,
Another liquid crystal display panel is arranged on the upper part of the liquid crystal display panel, and pressure is sequentially applied from the central portion of the upper part of the other liquid crystal display panel to the outer side by a crimping jig.

According to the first aspect of the present invention, even when the liquid crystal display panels are laminated by using the adhesive having a low viscosity, the adhesive is applied to the electrodes of the liquid crystal display panel by the panel sealing material. It can be prevented from flowing to the terminal portion.

Further, the method for laminating a liquid crystal display panel according to a second aspect of the present invention is characterized in that the panel sealing material is arranged at each side edge portion of each side of the liquid crystal display panel.

According to the second aspect of the present invention, the liquid crystal display panel and other liquid crystal display panels are made parallel to each other by being supported by the panel sealing material corresponding to each side of the liquid crystal display panel. Since the liquid crystal display panels can be stacked on top of each other, the gap size of each liquid crystal display panel can be kept uniform.

According to a third aspect of the present invention, there is provided a liquid crystal display panel laminating method, wherein the panel sealing material is a transparent substrate for adhering the pair of transparent substrates on the upper surface of the liquid crystal display panel. It is characterized in that it is arranged at a position corresponding to the sealing material for the substrate or outside the sealing material for the transparent substrate.

According to the third aspect of the invention, since the position corresponding to the transparent substrate sealing material is the non-display area of the liquid crystal display panel, the panel sealing material affects the display of the liquid crystal display device. Can be prevented.

Further, in the method for laminating a liquid crystal display panel according to the invention described in claim 4, after the other liquid crystal display panel is disposed above the liquid crystal display panel by adhering the adhesive, the other liquid crystal is placed. A weak pressure is applied to a position corresponding to the panel sealing material in the upper part of the display panel, and then the liquid crystal display panel and the other liquid crystal display panel are aligned with each other.

According to the invention described in claim 4, after the liquid crystal display panels are temporarily adhered by applying a weak pressure to the position corresponding to the panel sealing material, the liquid crystal display panels are transparent. The final alignment of the electrode pattern of the electrodes can be performed.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method for laminating a liquid crystal display panel according to the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view showing a first liquid crystal display panel laminated by using this embodiment, and FIG. 2 is a plan sectional view showing the first liquid crystal display panel shown in FIG. As shown in FIGS. 1 and 2, the first liquid crystal display panel 1 has a pair of transparent substrates 2, and a transparent electrode and an alignment film (not shown) are laminated on opposite surfaces of the transparent substrates 2. Has been done. The pair of transparent substrates 2 are integrally formed by adhering the transparent substrate sealing material 3 applied to the peripheral portions of the transparent substrates 2 to each other.
A space between them is filled with a cholesteric phase as liquid crystal (not shown). Further, an electrode terminal portion 4 in which the electrode terminals of the transparent electrodes are arranged is arranged at a position where each transparent substrate 2 is formed so as to project from another transparent substrate 2 among the transparent substrates 2.

Next, a method of laminating the liquid crystal display panel of this embodiment will be described.

First, as shown in FIG. 1, the first liquid crystal display panel 1 is mounted on a mounting table (not shown) so that the electrode terminals of the first liquid crystal display panel 1 face upward.

Next, on the upper surface of the transparent substrate 2 above the first liquid crystal display panel 1, the sealing material 3 for the transparent substrate is used.
The four panel sealing materials 7 are arranged by a screen printing method, a dispenser method, or the like outside the position corresponding to the above or the position corresponding to the transparent substrate sealing material 3.
Each of these panel sealing materials 7 is made of a material such as an epoxy resin, an acrylic resin, or the like, which has a high viscosity and does not have fluidity, such as a thermosetting resin or a photocurable resin. It is preferable that the panel sealing material 7 itself has an adhesive force. At this time, the respective panel sealing materials 7 are arranged so as to be parallel to the respective sides of the transparent substrate 2 and so that both ends of the other adjacent panel sealing materials 7 do not come into contact with each other.

Of these panel sealing materials 7, the panel sealing material 7 on the side of the electrode terminal portion 4 and the electrode terminal portion 4
The length dimension L of the panel sealing material 7 arranged at the position facing the panel sealing material 7 on the side is the length dimension L of the electrode terminal portion 4 which is the formation region of the plurality of electrode terminals arranged in alignment. The panel sealing material 7 is formed to be longer than that of the panel sealing material 7, and the panel sealing material 7 is formed to have the same size as the panel sealing material 7 arranged facing each other.
Further, the height dimension H of each of the panel sealing materials 7 is formed to be the same. Further, the width dimension W of each of the panel sealing members 7 is set such that a crushing force is applied to each of the panel sealing members 7 when the second liquid crystal display panel 9 laminated on the upper portion is pressure-bonded. When the panel sealing material 7 spreads on the upper surface of the transparent substrate 2, the dimension is such that the respective panel sealing materials 7 after spreading do not protrude from the width dimension W ′ of the transparent substrate sealing material 3. Is formed.

Next, as shown in FIG. 3, a thermosetting resin made of a material such as an epoxy resin or an acrylic resin having a low viscosity and a fluidity is formed in the central portion of the upper surface of the first liquid crystal display panel 1. An adhesive 11 formed of a material such as a photo-curable resin is dropped and attached. It should be noted that the material of the adhesive 11 and the material of the panel sealing material 7 may be the same in adhesive curing method. Thereby, the panel sealing material 7 and the adhesive 11 can be simultaneously cured by the same adhesive curing method.

Then, as shown in FIG. 4, the adhesive 1
1 flows and spreads on the upper surface of the transparent substrate 2, and then the second liquid crystal display panel 9 is moved to the first liquid crystal display panel 1
On top of.

Here, first, from the upper portion of the second liquid crystal display panel 9, a position on the upper surface of the second liquid crystal display panel 9 corresponding to each panel seal member 7 arranged on the first liquid crystal display panel 1. After a weak pressure is applied to temporarily bond the first liquid crystal display panel 1 and the second liquid crystal display panel 9, the first liquid crystal display panel 1 and the second liquid crystal display panel 9 are Align.

Next, as shown in FIG. 5, the crimping jig 13 made of a flexible material such as rubber or sponge, which is formed so that the central portion of the tip portion bulges, is attached to the second liquid crystal. It descends to the upper surface of the display panel 9, and the first liquid crystal display panel 1 and the second liquid crystal display panel 9 are pressure-bonded to each other. Thereby, the first liquid crystal display panel 1 and the second liquid crystal display panel 9
And are stacked.

Next, the operation of this embodiment will be described.

In the present embodiment, the panel sealing material 7 is arranged on the upper surface of the first liquid crystal display panel 1, and the panel sealing material 7 is arranged on the electrode terminal portion 4 side. Length L of the sealed panel sealing material 7
Is formed to be longer than the length dimension L ′ of the electrode terminal portion 4, so that the first liquid crystal display panel 1 and the second liquid crystal display panel are formed by using the liquid adhesive 11 having low viscosity. Even in the case of stacking 9 of the above, the sealing material 7 for each panel can prevent the adhesive 11 from flowing to the electrode terminal portion 4 of the first liquid crystal display panel 1.

The tip of the crimping jig 13 is formed so that its central portion bulges out.
By using the first liquid crystal display panel 1 and the second liquid crystal display panel 9
When and are pressed, pressure is first applied to the central portions of the liquid crystal display panels 1 and 9, and then pressure is applied to the outer sides of the liquid crystal display panels 1 and 9. Therefore, the adhesive 11
Flows outward from the central portions of the liquid crystal display panels 1 and 9, and the bubbles generated by the adhesive 11 leak from the gaps between the panel sealing materials 7.

Therefore, it is possible to prevent air bubbles from remaining in the gap between the first liquid crystal display panel 1 and the second liquid crystal display panel 9, and the first liquid crystal display panel 1 can be prevented.
It is possible to prevent the electrode terminal portion 4 of FIG. As a result, the electrode terminals of the first liquid crystal display panel 1 and the lead terminals of the flexible wiring board can be reliably connected.

Further, since the respective panel sealing materials 7 are arranged so as not to be connected to other adjacent panel sealing materials 7, the second liquid crystal display panel 9 is laminated on the first liquid crystal display panel 1. In this case, the excess adhesive 11 leaks from between the panel sealing materials 7. Therefore, the extra adhesive 11 does not press the liquid crystal display panels 1 and 9. Further, the four panel sealing members 7 are arranged so as to correspond to the sides of the first liquid crystal display panel 1 and to be parallel to the sides of the first liquid crystal display panel 1, and Since the height dimension H of each panel sealing material 7 is the same as the height dimension H of each other panel sealing material 7, the first liquid crystal display panel 1 and the second liquid crystal display panel 1
The gap size with the liquid crystal display panel 9 can be kept uniform. Furthermore, after temporarily adhering the liquid crystal display panels 1 and 9,
The final alignment of the electrode pattern of the transparent electrode in each of the liquid crystal display panels 1 and 9 can be performed. As a result, it is possible to obtain a good liquid crystal display element in which the transparent electrodes of the liquid crystal display panels 1 and 9 have no pattern shift.

Further, each panel sealing material 7 is the upper surface of the transparent substrate above the first liquid crystal display panel 1,
It is arranged outside the position corresponding to the transparent substrate sealing material 3 or the position corresponding to the transparent substrate sealing material 3, and the position corresponding to the transparent substrate sealing material 3 is in the first liquid crystal display panel 1. Since it is a non-display area, the panel sealing material 7 does not affect the display of the liquid crystal display device, and a good image can be displayed.

Further, it is possible to stack three or more liquid crystal display panels by the method of stacking liquid crystal display panels according to this embodiment. In this case, a method of simultaneously laminating three or more liquid crystal display panels is conceivable. According to this method, three or more liquid crystal display panels can be laminated in one laminating step, and the time required for the laminating step can be shortened. In addition, a method of first stacking two liquid crystal display panels and then stacking the two stacked liquid crystal display panels and another liquid crystal display panel may be considered. According to this method, each liquid crystal display panel can be easily aligned, and the stacking process can be facilitated.

In this embodiment, the four panel sealing materials 7 are arranged corresponding to the respective sides of the first liquid crystal display panel 1, but the invention is not limited to this.
If at least one panel sealing material 7 is arranged on the side of the first liquid crystal display panel 1 on the side of the electrode terminal portion 4, the electrode terminal portion 4 can be prevented from being contaminated and the adhesive 11 can be used. It is possible to prevent the generated bubbles from remaining in the gaps between the liquid crystal display panels 1 and 9. In this case, in order to keep the gap size between the liquid crystal display panels 1 and 9 uniform, a support member having the same height dimension as the height dimension H of the panel sealing material 7 is attached to the first liquid crystal display panel 1. It is advisable to dispose each side except the side on the side of the electrode terminal portion 4 on the upper surface and outside the position corresponding to the transparent substrate sealing material 3 or the position corresponding to the transparent substrate sealing material 3.

Further, the present invention is not limited to the above-mentioned embodiment, but various modifications can be made if necessary.

[0036]

EXAMPLES Next, examples of the present invention will be described.

When laminating the liquid crystal display panels, first, a first liquid crystal display panel having a size of 90 mm × 65 mm and a chiral nematic phase having a selective reflection center wavelength of 570 nm is filled, and the liquid crystal display panel. And the center wavelength of selective reflection is 45
Two liquid crystal display panels, a second liquid crystal display panel filled with a 0 nm chiral nematic phase, were prepared. The length of the electrode terminal of each liquid crystal display panel is 67 m.
m. In addition, the width dimension of the sealant for transparent substrate, which adheres the transparent substrate of each liquid crystal display panel, after pressure bonding was 2 mm.

First, the first liquid crystal display panel was mounted on the mounting table with the electrode terminals of the first liquid crystal display panel facing upward.

Next, on the upper surface of the transparent substrate above the first liquid crystal display panel, at a position corresponding to the sealing material for the transparent substrate, a thermosetting epoxy resin 4 is formed.
Two panel sealing materials were prepared by screen printing. The viscosity of the sealing material for each panel was 28 Pa · s. At this time, each of these panel sealing materials was arranged so as to be parallel to each side of the transparent substrate and not to be connected to another adjacent panel sealing material. Of these panel sealing materials, the panel sealing material on the electrode terminal side and the panel sealing material arranged at a position facing the panel sealing material are formed to have a length dimension of 75 mm, The other two panel sealing materials were formed to have a length dimension of 59 mm. Further, the height of each panel sealing material was formed to be 150 μm, and the width was formed so that the width of each liquid crystal display panel after lamination was 50 μm.

Then, 1 g of the adhesive was dropped on the central portion of the upper surface of the first liquid crystal display panel. For this adhesive, use one made of thermosetting epoxy resin,
The viscosity was 3.0 Pa · s.

After the adhesive was dropped, the adhesive was left for 30 seconds, and after the adhesive was wet and spread, a second liquid crystal display panel was laminated above the first liquid crystal display panel.

At this time, first, at the position corresponding to each panel sealing material on the upper surface of the second liquid crystal display panel,
A pressure of 8 Pa was applied to temporarily bond the first liquid crystal display panel and the second liquid crystal display panel. Then, in this state, the first liquid crystal display panel and the second liquid crystal display panel were aligned.

Next, heat of 70 ° C. is applied to the adhesive and the panel sealing material, and the adhesive and the panel sealing material are made of silicon rubber having a conical shape and a central portion of the tip portion bulging. The crimping jig is lowered to the central portion of the upper surface of the second liquid crystal display panel, and pressure is gradually applied from the central portions of the first liquid crystal display panel and the second liquid crystal display panel, and finally 1960 Pa. Pressure was applied. In this way, the first liquid crystal display panel and the second liquid crystal display panel were laminated.

As a result, the adhesive does not contaminate the portion of the electrode terminal portion of the first liquid crystal display panel that is connected to the lead terminal of the flexible wiring board, and the electrode terminal and the lead terminal are electrically connected. Did not have any problems.
In addition, no bubbles remained in the gap between the first liquid crystal display panel and the second liquid crystal display panel.

Further, the first liquid crystal display panel and the second liquid crystal display panel.
The gap dimension with the liquid crystal display panel could be made uniform. Furthermore, by performing final alignment of the electrode pattern of the transparent electrode in each liquid crystal display panel after the temporary adhesion, it was possible to manufacture a good liquid crystal display element without the pattern displacement of the transparent electrode in each liquid crystal display panel. .

[0046]

As described above, according to the liquid crystal display panel laminating method of the first aspect of the present invention, it is possible to prevent air bubbles from remaining in the gap between the liquid crystal display panels. In addition, it is possible to prevent the electrode terminal portion of the liquid crystal display panel from being contaminated. As a result, the electrode terminals of the liquid crystal display panel and the lead terminals of the flexible wiring board can be reliably connected.

According to the liquid crystal display panel laminating method of the second aspect of the present invention, since the gap size of each liquid crystal display panel can be kept uniform, the pattern of the transparent electrodes of each liquid crystal display panel can be maintained. It is possible to obtain a good liquid crystal display element having no deviation.

According to the liquid crystal display panel laminating method of the third aspect of the present invention, a good image can be displayed without the panel sealing material affecting the display of the liquid crystal display device. You can

Further, according to the liquid crystal display panel laminating method of the invention described in claim 4, each liquid crystal display panel is temporarily adhered by applying a weak pressure to a position corresponding to the panel sealing material. After that, since the final alignment of the electrode pattern of the transparent electrode in each liquid crystal display panel can be performed, it is possible to obtain a good liquid crystal display element in which the pattern of the transparent electrode of each liquid crystal display panel is not displaced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a case where a panel sealing material is arranged on a first liquid crystal display panel in a liquid crystal display panel laminating method according to the present invention.

FIG. 2 is a plan sectional view showing a first liquid crystal display panel shown in FIG.

FIG. 3 is a perspective view showing a case where an adhesive is dropped on the top of the first liquid crystal display panel in the liquid crystal display panel stacking method according to the present invention.

FIG. 4 is a perspective view showing a case where the height dimension of the adhesive shown in FIG. 3 flows to a height dimension similar to the height dimension of the panel sealing material.

FIG. 5 is a perspective view showing a case where a crimping jig is lowered onto the upper part of the second liquid crystal display panel in the liquid crystal display panel stacking method according to the present invention.

[Explanation of symbols]

1st liquid crystal display panel 2 transparent substrate 3 Sealing material for transparent substrates 4 electrode terminals Sealing material for 7 panels 9 Second liquid crystal display panel 11 adhesive 13 Crimping jig H Panel seal height Width dimension of W panel sealant L panel seal length L'Length of transparent electrode sealing material

Continued front page    F term (reference) 2H088 FA01 FA18 MA01                 2H089 HA21 QA12 QA16                 5C094 AA42 AA43 BA07 BA43 DA03                       DA11 DB03 GB01                 5G435 AA16 AA17 BB12 CC12 DD01                       EE33 KK02

Claims (4)

[Claims] 1. The liquid crystal display panel is mounted so that a plurality of electrode terminal portions aligned on one of the pair of transparent substrates constituting the liquid crystal display panel face upward,
On the upper surface of the other transparent substrate constituting the liquid crystal display panel, at least on the side edge portion on the side where the electrode terminals are formed, the electrode terminal portion that is a formation region of the plurality of aligned electrode terminals is formed. After forming a high-viscosity panel sealing material having a length dimension longer than the length dimension, a low-viscosity adhesive is attached to the central portion of the upper surface of the liquid crystal display panel, and another liquid crystal display panel is attached to the liquid crystal A method for laminating a liquid crystal display panel, wherein the liquid crystal display panel is arranged on an upper portion of the display panel, and pressure is sequentially applied from a central portion of an upper portion of the other liquid crystal display panel to the outer side by a pressure bonding jig. 2. The method for laminating a liquid crystal display panel according to claim 1, wherein the panel sealing material is arranged at each side edge portion of each side of the liquid crystal display panel. 3. A sealing material for the panel is provided on the upper surface of the liquid crystal display panel at a position corresponding to the sealing material for the transparent substrate for adhering the pair of transparent substrates, or more than the sealing material for the transparent substrate. The method for laminating a liquid crystal display panel according to claim 1 or 2, characterized in that the liquid crystal display panel is arranged outside. 4. After the other liquid crystal display panel is placed above the liquid crystal display panel by adhering the adhesive, a position corresponding to the panel sealing material is located above the other liquid crystal display panel. 4. A method for laminating a liquid crystal display panel according to claim 1, wherein a weak pressure is applied to the liquid crystal display panel, and then the liquid crystal display panel and the other liquid crystal display panel are aligned with each other.