JPH04362921A - Manufacture of liquid crystal display element - Google Patents

Abstract

PURPOSE:To prevent a transparent electrode from being dissolved in drops of water gathering in the part surrounded with an upper and a lower electrode substrate and a peripheral sealing material. CONSTITUTION:After the upper and lower substrates 11 and 12 are fixed across the sealing material positioned inside their peripheral end surfaces, the upper and lower substrates 11 and 12 are hermetically sealed while liquid crystal is charged; and organic resin 16 is applied and cured at the recessed part which is formed of the peripheral part internal surfaces of the upper and lower substrates 11 and 12 and the external surface of the sealing material and where the electrode is extended.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method of manufacturing a liquid crystal display element.

The present invention relates to applying an organic adhesive to fill the gap between the upper and lower electrode substrates and the peripheral sealing material. The present invention provides a liquid crystal display element.

0003

2. Description of the Related Art In general, the structure of a liquid crystal display element is such that an envelope is formed by bonding the periphery of upper and lower substrates 1 and 2, on which upper and lower electrodes 1a and 2a are respectively formed, with a sealing material 3, as shown in FIG. Afterwards, a liquid crystal substance is injected inside.

Now, when manufacturing one such liquid crystal display element by assembling a pair of upper and lower substrates 1 and 2, as shown in FIG.
There can be no gap at all between them, resulting in a highly reliable product.

[0005]However, this single-chip manufacturing process involves complicated steps and is not rational, so recently, devices have been manufactured using a multi-chip manufacturing method. As shown in FIG. 3, this multi-piece manufacturing method involves making a large number of upper and lower electrodes on one large substrate 11, 12, stacking two identical substrates 11, 12 and sealing them with a sealing material 13, and cutting lines 14. A large number of devices can be manufactured at once by cutting the device. In this method, the upper and lower substrates 11 and 12 are bonded together with the sealing material 13 and then cut.
As shown, upper and lower substrates 11 and 12 and peripheral sealing material 13
A gap 15 must be created between the two. This is because even if the sealing material 13 is, for example, epoxy resin or frit glass, it is impossible to cut above the bonded portion. Note that 11a and 12a indicate upper and lower electrodes, respectively.

[0006]

[Problem to be solved by the invention] In this way, the gap 15
If the element is left in a high humidity atmosphere,
Water droplets accumulate in the gap 15 mentioned above. Therefore, when electricity is applied with water droplets accumulated, current flows between the terminals or between the common side electrode and the terminal, and after a long period of time, the transparent conductive film on the terminal side or the common side This results in the dissolution of In2O3 as the main component. In particular, in an element using frit glass, if the element is left in a high humidity atmosphere for a long period of time even when no current is applied, the transparent conductive film dissolves more noticeably than in the case of an organic seal element. When manufacturing a liquid crystal element using a multi-crystal process, it is impossible to eliminate the gap 15 described above. When water droplets accumulate, the phenomenon of dissolution of the transparent conductive film always occurs.

The present invention is intended to suppress the above-mentioned transparent electrode dissolution phenomenon, and an object of the present invention is to provide a method for manufacturing a liquid crystal display element that can be applied whether the sealing part is made of organic adhesive or frit glass. .

[0008]

[Means for Solving the Problems] In order to achieve the above object, the method for manufacturing a liquid crystal display element according to the present invention includes forming upper and lower substrates on which electrodes are formed such that the electrodes face each other with a predetermined interval. After fixing the upper and lower substrates inward from their peripheral end surfaces via a sealing material, sealing liquid crystal between the upper and lower substrates and airtightly sealing them, the inner surfaces of the peripheral parts of the fixed upper and lower substrates are sealed. The present invention is characterized in that an organic resin is applied and hardened to a portion of the recess formed by the electrode and the outer surface of the sealing material, where the electrode extends.

[0009]

[Operation] The fixation of the upper and lower substrates, which requires strength, is done through the sealing material placed inside the peripheral edges of the upper and lower substrates, which not only ensures the fixation strength, but also enables mass production of multiple pieces. method can be adopted. The organic resin applied to improve the moisture resistance of the electrodes in the recesses around the substrate and the sealant for fixing the upper and lower substrates are applied and cured independently, so choose the one that suits your purpose, application method, and timing. The selection range is expanded.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to illustrated embodiments.

FIG. 1 is a sectional view of a liquid crystal display element for explaining an embodiment of the method for manufacturing a liquid crystal display element according to the present invention. Note that the same or equivalent members as in FIG. 4 are denoted by the same reference numerals, and the explanation thereof will be omitted. The device manufactured by the multi-piece manufacturing process as described above is broken into one piece, and after filling the liquid crystal, the filling hole is hermetically sealed. Then, the upper and lower substrates 11
, 12 and the peripheral sealing material 13, a liquid epoxy resin 16 such as Epikote 828 is coated with a linear amine such as TTA (triethyltetraamine) added as a curing agent. A good application method is to drop the resin 16 onto the end of the element and allow the resin 16 to flow under its own weight. After coating, the element is left at 80° C. for 60 minutes to harden the resin 16. Or as resin 16, epoxy resin Epicoat 828
A polyamide resin is added to the mixture, and 2 to 5 Phr of γ-aminotriethoxysilane is added. Furthermore, SiO2 powder (particle size of 5 μm or less) is added and ethyl cellosolve is added and mixed to prepare an adhesive for embedding. Then, it is applied as described above, and after application, the solvent is removed at room temperature, and then it is cured at 100° C. for 60 minutes.

In the present invention, the fixing of the upper and lower substrates, which require strength from the viewpoint of reliability, is performed through the sealing material disposed inside the peripheral edges of the upper and lower substrates.
A multi-piece method with high mass production efficiency can be adopted. At this time, an organic resin is applied to the part of the recess formed around the substrate where the electrode extends in order to prevent the electrode from dissolving due to moisture entering the recess. Since the coating film is not required to have much strength, it is sufficient to apply and cure an organic resin with a low curing temperature. The curing temperature of organic resin sealants for fixing the upper and lower substrates is usually 150°C or higher, but since organic resins with low curing temperatures can be used, this coating and curing work can be performed even after the liquid crystal is injected into the liquid crystal cell. I can do it.

Since the distance between the two substrates fixed by the sealant is usually 10 μm or less, even if the organic resin is applied to the recess, it is difficult to completely fill the recess, and the micropores are difficult to fill. may occur. If such micropores are formed before the liquid crystal is injected into the liquid crystal cell, if liquid crystal or the like enters into these areas when the liquid crystal is injected, it cannot be easily removed even by cleaning. In other words, resin is applied to the recesses to prevent moisture from entering, but once pinholes are formed in this coating and the liquid crystal material has entered the pinholes, it is difficult to remove the resin. This makes it difficult and even has a negative impact. Therefore, it is a great advantage to be able to apply the organic resin to this recess as late as possible in the manufacturing process.

[0014]

Effects of the Invention As is clear from the above description, the method for manufacturing a liquid crystal display element according to the present invention involves sealing the liquid crystal between the upper and lower substrates and then sealing them between the inner surfaces of the peripheral parts of the upper and lower substrates and the outer surface of the sealing material. Since the organic adhesive is filled in the recesses surrounded by the recesses, the transparent electrode is prevented from dissolving due to water droplets in the recesses.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of a liquid crystal display element for explaining an embodiment of a method for manufacturing a liquid crystal display element according to the present invention.

FIG. 2 is a sectional view of a main part of a liquid crystal display element produced by a conventional method of manufacturing a single-piece liquid crystal display element.

FIG. 3 is a front view for explaining a multi-piece production method.

FIG. 4 is a sectional view of a main part of a liquid crystal display element obtained by the method of FIG. 3;

[Explanation of symbols]

11...Top board 12...lower board 13...Sealing material 16...Resin

Claims (1)

[Claims] 1. After fixing upper and lower substrates on which electrodes are formed, with the electrodes facing each other with a predetermined interval, inside the peripheral end surfaces of the upper and lower substrates via a sealing material, After the liquid crystal is sealed between the lower substrates and hermetically sealed, a portion of the recess formed by the inner surfaces of the peripheral portions of the fixed upper and lower substrates and the outer surface of the sealing material, in which the electrodes extend, is placed. A method for manufacturing a liquid crystal display element, characterized by coating and curing an organic resin.