JP2010032775A - Ferroelectric liquid crystal display element, and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of color unevenness due to contraction of a ferroelectric liquid crystal when returned to a room temperature. <P>SOLUTION: A manufacturing method of a ferroelectric liquid crystal display element includes at least: a step of forming an alignment control film on a mother silicon substrate having a plurality of liquid crystal display areas formed thereon; a step of forming an alignment control film on a mother glass substrate; a step of providing a sealant forming liquid crystal inlets on outer peripheries of respective image display areas and sticking the mother silicon substrate and the mother glass substrate to each other; a step of cutting them in outer peripheries of the sealant into individual ferroelectric liquid crystal display element parts; a step of applying and hardening an adhesive having a high curing shrinkage over a pair of substrate sides of each ferroelectric liquid crystal display element; and a step of injecting a high-temperature ferroelectric liquid crystal to the ferroelectric liquid crystal display element. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ferroelectric liquid crystal display element and a method for manufacturing the same.

  Liquid crystal display elements are used in a wide range of fields, taking advantage of their thinness and low power consumption. In recent years, liquid crystal display elements using ferroelectric liquid crystals have been used due to the fast response time of liquid crystals.

  FIG. 2 is a top view for explaining a method of forming a liquid crystal display element. A plurality of liquid crystal display element regions (D 1 to D 9) are formed on the two mother substrates 10 and are pasted via the seal member 3. After the seal member 3 is cured, the seal member 3 is cut into the liquid crystal display element shown in FIG.

  3A and 3B are diagrams showing the structure of the liquid crystal display element, in which FIG. 3A is a top view, FIG. 3B is an AA cross-sectional view, and FIG. A substrate 1 on which a plurality of pixel electrodes 5 are formed and a transparent substrate 2 on which a common electrode (not shown) facing the pixel electrodes 5 is pasted by a seal member 3. A liquid crystal injection port 4 is formed in a part of the seal member 3. In this figure, the substrate 1 and the substrate 2 are offset as shown in FIG.

  A liquid crystal is injected from a liquid crystal injection port 4 into a space formed by the substrate 1, the substrate 2, and the seal member 3, and a vacuum injection method is generally used. In the vacuum injection method, the air in the space is exhausted by evacuation, and then liquid crystal is applied to the vicinity 4A of the liquid crystal injection port by supplying, dropping, or the like, and using the capillary phenomenon and the pressure difference inside and outside the liquid crystal display element, Is injected into the space. After the injection, the liquid crystal injection port 4 is sealed. Since the ferroelectric liquid crystal has no fluidity at room temperature, the liquid crystal was heated with a heater to reduce the viscosity and injected. (See Patent Document 1)

JP 2008-70717 A

  The ferroelectric liquid crystal display device according to the present invention has a structure in which a spacer for securing a gap between two substrates is mixed in the seal member, but no spacer is provided on the inner side surrounded by the seal member. Therefore, in the method of injecting a ferroelectric liquid crystal at a high temperature into the ferroelectric surface liquid crystal display element, the substrate after the ferroelectric liquid crystal is injected due to the shrinkage when the ferroelectric liquid crystal injected at a high temperature returns to room temperature. Since the interval between them becomes non-uniform (the central portion of the substrate is recessed and the liquid crystal layer becomes thin), color unevenness occurs.

  The present invention prevents the occurrence of color unevenness in a ferroelectric display device injected with a ferroelectric liquid crystal at a high temperature so that the substrate spacing does not become non-uniform when the ferroelectric liquid crystal returns to room temperature. It is an object.

  At least a pair of substrates on which an alignment control film is formed, a seal member for bonding by providing an injection port for injecting ferroelectric liquid crystal in a part of the periphery of the pair of substrates, and injection from the injection port Ferroelectric liquid crystal display element comprising a ferroelectric liquid crystal and a sealing material for sealing the injection port, and a cure shrinkage rate across a pair of substrate side surfaces of the ferroelectric liquid crystal display element A ferroelectric liquid crystal display element in which a ferroelectric liquid crystal is injected is applied and cured.

  At least a step of forming an alignment control film on a mother silicon substrate on which a plurality of liquid crystal display regions are formed, a step of forming an alignment control film on a mother glass substrate, and a seal member that forms a liquid crystal injection port on the outer periphery of each image display region A step of providing and bonding the mother silicon substrate and the mother glass substrate, a step of cutting into individual ferroelectric liquid crystal display element portions on the outer periphery of the sealing member, and side surfaces of a pair of substrates of the ferroelectric liquid crystal display element A method for manufacturing a ferroelectric liquid crystal display device comprising: a step of applying and curing an adhesive having a high cure shrinkage across the substrate; and a step of injecting a ferroelectric liquid crystal at a high temperature into the ferroelectric liquid crystal display device And

By applying and curing an adhesive with high curing shrinkage across the side surfaces of a pair of ferroelectric liquid crystal display elements, the center of the substrate becomes convex, and high temperature ferroelectric liquid crystal FLC that is heated and expanded is injected. Thereafter, when the temperature of the ferroelectric liquid crystal FLC decreases, the ferroelectric liquid crystal FLC contracts, and a flat ferroelectric liquid crystal display element is obtained.

  At least a step of forming an alignment control film on a mother silicon substrate on which a plurality of liquid crystal display regions are formed, a step of forming an alignment control film on a mother glass substrate, and a seal member that forms a liquid crystal injection port on the outer periphery of each image display region A step of providing and bonding the mother silicon substrate and the mother glass substrate, a step of cutting into individual ferroelectric liquid crystal display element portions on the outer periphery of the sealing member, and side surfaces of a pair of substrates of the ferroelectric liquid crystal display element A method for manufacturing a ferroelectric liquid crystal display device comprising: a step of applying and curing an adhesive having a high cure shrinkage across the substrate; and a step of injecting a ferroelectric liquid crystal at a high temperature into the ferroelectric liquid crystal display device And

  FIG. 1 is a cross-sectional view (corresponding to FIG. 3C) for explaining a method of manufacturing a ferroelectric liquid crystal display device according to the present invention, where (A) is after cutting and (B) is after applying an adhesive. (C) shows the state after the adhesive is cured, and (D) shows the state after the ferroelectric liquid crystal is injected and cooled.

  In this embodiment, the substrate 1 is a single crystal silicon substrate on which TFTs and a network are formed, and has an outer shape of 9.45 × 15.31 mm and a thickness of 0.625 mm. A pixel electrode 11a made of an aluminum film 11 is formed on the upper surface, and an alignment control film 13 made of polyimide is formed thereon. The substrate 2 is a glass substrate, the outer shape is 9.45 × 15.31 mm, and the thickness is 0.725 mm. A transparent common electrode 12 and an alignment control film 13 are laminated. The alignment control films are opposed to each other, and are bonded together through the seal member 3 in which the spacers 14 are mixed. In practice, as described with reference to FIG. 2, a plurality of liquid crystal display element regions are formed on a mother substrate and cut (divided) in FIG. 1A. In this state, the gap T between the two substrates is determined by the spacer 14 and is uniform.

  The size of the affixing part is 8.45 × 15.31 mm, but the outer circumference of the seal member 3 and the side surfaces of the substrates 1 and 2 are provided with a width of W = 100 μm as shown in the figure and straddle the two substrates 1 and 2. The adhesive 15 is applied as described above. (FIG. 1 (B)) The adhesive 15 has a high shrinkage ratio upon curing, and is, for example, an ultraviolet curable resin TB3026E (curing shrinkage ratio 7.5%) manufactured by ThreeBond. As ultraviolet irradiation conditions, the irradiation center wavelength is 365 nm, the irradiation intensity is 80 mW, and the adhesive 15 is cured in 100 seconds.

  As the adhesive 15 is cured, the adhesive 15 contracts, and a tensile force is applied in the direction (arrow direction in the figure) in which the gap T (0.7 μm in this example) decreases near the side surface of the substrate. Thus, the center of the substrate is bent. (FIG. 1 (C)) Since the substrate is single crystal silicon and glass, it is deformed and maintained mainly so that the central portion on the glass substrate 2 side is convex.

  A high-temperature (110 ° C.) ferroelectric liquid crystal FLC that has been heated and expanded is injected, and then contracts when the temperature of the ferroelectric liquid crystal FLC decreases, so that the substrate 2 is pulled in the direction of the arrow (FIG. 1D). The gap between the two substrates is uniform.

  The above conditions are only examples, and vary depending on the thickness, size, material, ferroelectric liquid crystal properties, type of adhesive, etc. of the substrate, and are not generally determined. Become.

  As a result, the gaps between the substrate 1 and the substrate 2 become uniform, and the occurrence of uneven color, which was a problem, can be eliminated.

Sectional drawing for demonstrating the manufacturing method of the ferroelectric liquid crystal display element by this invention Top view with a view for explaining a method of forming a liquid crystal display element FIGS. 3A and 3B are diagrams illustrating a structure of a liquid crystal display element, in which FIG. 3A is a top view, FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Substrate 3 Sealing member 4 Liquid crystal inlet 4A Near liquid crystal inlet 5 Pixel electrode 10 Mother substrate 11 Aluminum thin film 11a Pixel electrode 12 Common electrode 13 Orientation control film 14 Spacer 15 Adhesive FLC Ferroelectric liquid crystal

Claims (2)

  At least a pair of substrates on which an alignment control film is formed, a seal member for bonding by providing an injection port for injecting ferroelectric liquid crystal in a part of the periphery of the pair of substrates, and injection from the injection port Ferroelectric liquid crystal display element comprising a ferroelectric liquid crystal and a sealing material for sealing the injection port, and a cure shrinkage rate across a pair of substrate side surfaces of the ferroelectric liquid crystal display element A ferroelectric liquid crystal display element, wherein a ferroelectric liquid crystal is injected by applying and curing a high adhesive. at least,
Forming an alignment control film on a mother silicon substrate on which a plurality of liquid crystal display regions are formed;
Forming an orientation control film on the mother glass substrate;
A step of providing a sealing member that forms a liquid crystal injection port on the outer periphery of each image display region and bonding the mother silicon substrate and the mother glass substrate;
Cutting into individual ferroelectric liquid crystal display elements on the outer periphery of the sealing member;
Applying and curing an adhesive having a high curing shrinkage rate across a pair of substrate side surfaces of the ferroelectric liquid crystal display element;
Injecting a ferroelectric liquid crystal at a high temperature into the ferroelectric liquid crystal display element;
A method for manufacturing a ferroelectric liquid crystal display element, comprising:

Images