JPH01138538A - Production of liquid crystal cell - Google Patents

Abstract

PURPOSE:To eliminate problems in appearance such as Newton's rings and to provide the title device which is strong to impact and is robust by adhering two sheets of liquid crystal cells over the entire surface. CONSTITUTION:An epoxy adhesive agent 2 is printed in the peripheral part of the display part on an upper transparent substrate 11b of the lower liquid crystal cell and a sealing port to be sealed therein with the adhesive agent afterward is previously opened thereto. The upper liquid crystal cell is laminated on the printed lower liquid crystal cell and the two cells are tentatively adhered by the adhesive agent 15. The low-viscosity epoxy adhesive agent 16 is then vacuum-injected into the spacing between the upper and lower liquid crystal cells and is cured to adhere two sheets of the liquid crystal cells over the entire surface. Impact resistance is thereby improved and the robust structure is obtd. Since the display surface is adhered by the transparent adhesive agent, the generation of the Newton's rings is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a liquid crystal device used in word processors, personal computer terminals, televisions, video display devices, measuring instruments, vehicle instrument panels, and the like.

[Summary of the invention]

The present invention relates to a two-layer liquid crystal device in which two liquid crystal cells are stacked to achieve high contrast and achromatic color.By bonding both cells together on the entire surface, appearance problems such as Newton's rings can be avoided. The present invention provides a method for manufacturing a two-layer liquid crystal device that is strong against removal and impact.

[Conventional technology]

Two-layer liquid crystal devices include a guest-host type liquid crystal device, as shown in Figure 3, in which two panels with different alignment directions are stacked to improve contrast, and a 18-layer liquid crystal device as shown in Figure 4.
An SBE type liquid crystal device having a helical structure of 0° or more is laminated with a reversely rotating color correction liquid crystal panel to eliminate the colors peculiar to SBE and make black and white display possible.

The former has already been put into practical use as in-vehicle instrument panels, and the latter has begun to be commercialized as word processors and personal computer terminals, and it is thought that its applications will continue to expand in the future.

The structure of these two-layer liquid crystal devices is as shown in Figures 3 and 4, where the liquid crystal panels are sandwiched between them by spacers 35 and held in a housing, or in the case of the former, three transparent substrates constitute a two-layer integrated liquid crystal panel. A method is being taken.

[Problem that the invention seeks to solve]

However, the structure in which two panels are held together by a spacer and a housing has reliability problems such as impact resistance.

Moreover, since it is impossible to maintain a constant cell spacing in the display section, this structure has an appearance problem in that Newton's rings form.

In addition, the method of constructing a two-layer liquid crystal panel using three transparent substrates complicates the manufacturing process and results in an expensive display device.Especially in the case of SBH, the thickness of the liquid crystal layer must be controlled with high precision. This makes manufacturing virtually impossible.

[Means for solving problems]

In order to solve the above problems, the present invention is to adhere the entire surface of a liquid crystal cell. Specifically, firstly, adhesive is applied to areas other than the display area by a printing method, two liquid crystal cells are temporarily bonded using the adhesive layer, and secondly, from the injection port of the adhesive layer,
A transparent adhesive is injected into the display area to adhere the entire surface of the liquid crystal cell.

[Effect]

The result is an extremely robust structure with improved impact resistance even without being held in place by a housing. Furthermore, since the display surface is bonded with a transparent adhesive, it is possible to suppress the occurrence of Newton's rings.

〔Example〕

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 1 is a schematic cross-sectional view of an embodiment of the present invention.

In the figure, lla, 12a, llb, and 12b are transparent substrates,
1) "+12a is the transparent substrate of the upper liquid crystal cell, llb,
12b is a transparent substrate of the lower liquid crystal cell. Liquid crystal layers 13a and 13b are sandwiched between the transparent substrates, and a sealant 1 is applied to the liquid crystal layers 13a and 13b.
4a and 14b. The two liquid crystal cells configured in this manner are stacked in the following manner.

First, an epoxy adhesive 21 is applied by screen printing onto the upper transparent substrate of the lower liquid crystal cell in the shape shown in FIG.
is printed around the display area. However, as shown in FIG. 2, an opening for filling the adhesive later is left open. Then,
The upper liquid crystal cell is laminated on the printed lower liquid crystal cell and temporarily adhered with adhesive 15 as shown in FIG. Even if the epoxy adhesive is colored or has some air bubbles mixed in, there is no problem in appearance since it is outside the display area.

Second, vacuum inject low-viscosity epoxy adhesive 16 into the gap between the upper and lower liquid crystal cells. Next, irradiate with an 80W ultraviolet lamp for 15 seconds, the epoxy will harden and the two liquid crystal cells will be bonded together on the entire surface. be done. Since the epoxy adhesive was transparent and did not generate bubbles, there was no problem in appearance and the generation of Newton's rings could be completely prevented.

〔Effect of the invention〕

As described above, the present invention relates to a two-layer liquid crystal device in which two liquid crystal cells are stacked to achieve high contrast and achromatic color. This problem can be eliminated, and a 2N-type liquid crystal device that is robust and resistant to impact can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of an embodiment of the present invention, FIG. 2 is a diagram of the peripheral seal shape of the embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view of an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of a conventional liquid crystal display device. 1)a, 12a...Transparent substrate of upper liquid crystal cell 1)b,
12b...Transparent substrates 13a, 13b of lower liquid crystal cell
...Liquid crystal layer 14a, 14b...Sealant 15, 16...Adhesive Applicant: Seiko Electronics Co., Ltd. +3b Cross-sectional view of the seed hole of an excellent example of Kikamei Fig. 1 Conventional liquid crystal Indication Form 1 A' Senbetsu View Figure 3 Figure 2 Funeral Figure 4

Claims (2)

[Claims] (1) A method for manufacturing a liquid crystal device in which two liquid crystal cells each having a liquid crystal sandwiched between a pair of transparent substrates are stacked, the method comprising bonding the two liquid crystal cells on their entire surfaces. (2) The method of gluing the two liquid crystal cells together is: firstly, the two liquid crystal cells are temporarily bonded by applying adhesive to areas other than the display area, and secondly, the two liquid crystal cells are attached to the display area between the two liquid crystal cells. 2. The method of manufacturing a liquid crystal device according to claim 1, wherein the two liquid crystal cells are bonded over the entire surface by injecting and curing an adhesive.