JP2009042560A - Method for manufacturing small liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently polish a small liquid crystal display element which has no spacer between pixel electrodes. <P>SOLUTION: The method for manufacturing a small liquid crystal display element includes: forming a plurality of small liquid crystal display element regions on a pair of mother substrates; sticking the pair of mother substrates to each other via sealing materials formed on outer peripheries of the respective small liquid crystal display element regions without any spacer between the pixel electrodes and via a sealing material formed on outer peripheries of the mother substrates; and polishing at least one of the mother substrates. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a small liquid crystal display element.

  Liquid crystal display elements are often used in place of cathode ray tubes as thin flat display elements. 2 and 3 are cross-sectional views of typical liquid crystal display elements. As the liquid crystal display element, there are a transmissive liquid crystal display element in which a liquid crystal 3 is sealed between two transparent substrates 1 and 2 via a sealing material 4, and a reflective liquid crystal display element in which one substrate is a silicon substrate.

  In FIG. 2, the distance between the transparent substrate 1 and the transparent substrate 2 is determined only by the sealing material 4 containing a spacer (not shown), and is used when the transparent substrate is thick and has high rigidity. FIG. 3 shows a case where the distance between the transparent substrate 1 and the transparent substrate 2 is determined by a large number of spacers 5 and is adopted when the transparent substrate is thin and has low rigidity.

  The thickness of the transparent substrate was about 1.1 mm in the old days, but thinning of the liquid crystal display element is required, and recently, the thickness of about 0.7 mm and further about 0.3 mm is used. However, a thin substrate is difficult to handle, and there are many restrictions on the production of liquid crystal display elements. Moreover, the thinner the substrate is, the smaller the substrate area is (when it is larger, the substrate is broken by handling), and the productivity of the liquid crystal display element is worsened. Therefore, a manufacturing method is adopted in which after two substrates are bonded together, at least one of the substrates is polished and thinned.

For example, a method is disclosed in which a transparent electrode is formed on a pair of glass substrates having a thickness of 1.1 mm, bonded together with a liquid crystal sealing interval, and then the glass substrate is thinned by a lapping polishing method or the like. (See Patent Document 1)
Compared to using a thin glass substrate from the beginning, handling is easy and workability can be improved.

As shown in FIG. 3, particles having a fixed particle diameter or columns (spacers 5) having a fixed particle size are interposed between a pair of substrates, and the pair of substrates are held and fixed to each other, and liquid crystal is attached to the intervals. A method is disclosed in which at least one of the pair of substrates is polished in any step before or after filling with and sealing. (Patent Document 2)
By holding the spacer 5 between the pair of substrates and maintaining a constant interval, the substrate can be prevented from being cracked or chipped due to the bending of the substrate, and thus is suitable for thinning. Further, there is a description that the substrate is divided into a plurality of liquid crystal display elements as a large mother substrate, and examples of polishing before and after the division are disclosed.
JP-A-5-61011 JP 2000-214442 A

  In the manufacturing method described in Patent Document 1, as described in Patent Document 2, the substrate is bent, and the substrate is cracked or chipped. In the manufacturing method described in Patent Document 2, particles having a fixed particle size and columns having a fixed height must be interposed between a pair of substrates. It is preferable to use spacers such as particles and pillars for liquid crystal display elements that are magnified and viewed (for viewfinder) and for magnified display (for projectors) because the particles and pillars are magnified and the image deteriorates. Absent.

  A plurality of small liquid crystal display element regions are formed on a pair of mother substrates, and a sealant formed on the outer periphery of each small liquid crystal display element region without a spacer between pixel electrodes and a sealant formed on the outer periphery of the mother substrate A manufacturing method of a small liquid crystal display element in which at least one of the mother substrates is attached and polished.

  In the method for manufacturing a small liquid crystal display element, a method for manufacturing a small liquid crystal display element in which a plurality of peripheral sealing materials for the mother substrate are formed and polished.

  In the method for manufacturing a small liquid crystal display element, a method for manufacturing a small liquid crystal display element in which a pair of mother substrates is sealed with a positive pressure and polished.

  When a small liquid crystal display element region having a display pixel portion having a diagonal of about 20 mm is formed in a matrix shape in the mother substrate, the spacing between the sealing materials is about 16 mm or less, so that each sealing material becomes a reinforcing material instead of the spacer, It is possible to prevent the substrate from being bent.

  By forming and sealing a sealing material on the outer periphery of the mother substrate, the portion where the small liquid crystal display area is not formed is reinforced, and the outermost periphery is affixed, so that bending of the entire substrate during polishing can be prevented. By forming a plurality of outer peripheral sealing materials, it is possible to prevent water immersion and contamination during polishing from the portion sealing the opening of the sealing material.

  By sealing by applying a positive pressure between the pair of substrates at the time of sealing the outer periphery, unevenness in the interval between the substrates, dents, and the like can be prevented in portions where there is no sealing material during polishing. Further, since the inside of the seal is positive pressure, it is possible to further prevent water immersion and contamination during polishing.

  A plurality of small liquid crystal display element regions are formed on a pair of mother substrates, and a sealant formed on the outer periphery of each small liquid crystal display element region without a spacer between the image electrodes and a sealant formed on the outer periphery of the mother substrate A manufacturing method of a small liquid crystal display element in which at least one of the mother substrates is attached and polished.

  FIG. 1 is a view for explaining a method of manufacturing a small-sized liquid crystal display device according to the present invention, and is a top view (A) and a cross-sectional view AA. In this example, 64 liquid crystal display element regions 6 having an outer shape of 13 × 17 mm are formed on a circular substrate having a diameter of 6 inches. The liquid crystal display element region 6 formed by the sealing material 4 is formed at the center of the circular substrate, and double sealing materials 7 and 8 are formed on the outer periphery of the circular substrate. Since the liquid crystal display element is small, as can be seen from the cross-sectional view (B), a large number of sealing materials 4 formed in each small liquid crystal display element region are formed, as if the spacer 5 shown in FIG. Since the sealing materials 7 and 8 are formed on the outer periphery of the circular substrate, the two substrates are completely attached, and the occurrence of warpage of the substrate can be suppressed during polishing of the circular substrate. The space between the substrates is empty except for the sealing material, but since they are integrated, the total thickness can be polished to about 0.3 mm.

  FIG. 4 is a top view showing the shape of the sealing material formed in plural (three steps in this example) on the outer periphery of the circular substrate, and FIG. 5 is a partial top view for explaining the sealing method.

  In FIG. 4, the small liquid crystal display element regions 6 (not shown) are collectively formed on the inner periphery of the dotted line 10. Three stages of sealing materials 7, 8, and 9 are formed on the outer periphery of the circular substrate. In this example, the seals 7a, 8a, 9a, 7b, 8b, and 9b are formed by two cuts in the lateral direction. The reason is that the outer peripheral sealing material is formed mainly to prevent the polishing liquid or the cooling liquid from entering the small liquid crystal display element region when the substrate is polished or cut. This is because a hole for escaping the gas between the substrates is necessary when attaching the film.

  When the application of the substrate is completed, the sealing is closed, but it must be sealed for the main purpose. Since the width of the sealing material is 400 μm to 1000 μm and the distance between the substrates is 1 to 3 μm, it is difficult to reliably seal and seal, and it is desirable to perform multiple sealing as in this example.

  As shown in FIG. 5 (A), the sealing 9a is first sealed with a sealing material, then the sealing 8a is sealed with a sealing material as shown in (B), and finally as shown in (C). The sealing 7a and the outer peripheral side surface of the substrate are sealed. The sealing material is suitable for the ultraviolet curable type, and the operation is performed in three stages. As shown in the figure, even when the sealing material does not enter well, the object can be achieved by irradiating only the sealing portion with ultraviolet rays in the first stage and the second stage.

  When such sealing is finished and polishing is performed, the sealing material on the outer peripheral side surface of the substrate may be peeled off, but the sealing material sealed in three steps has a long seal creepage distance, so a small liquid crystal display element region portion It is possible to prevent the polishing liquid and the cooling liquid at the time of cutting from entering.

  This example is an example of sealing in a state where the inside of the sealing material 9 is set to a positive pressure when the first stage sealing 9a of the embodiment is sealed. The interior is 304 hPa. A positive pressure higher than (hectopascal) is recommended. More preferably, 506 hPa. Between 304 hPa and 304 hPa, even if there is a leak in the sealing part, it becomes difficult for the polishing liquid and the cooling liquid at the time of cutting to enter the sealing part, and the thinned substrate is prevented from being dented during polishing. it can.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the manufacturing method of the small-sized liquid crystal display element by this invention, a top view (A) and AA sectional drawing (B). Cross-sectional view of a typical liquid crystal display element Cross-sectional view of a typical liquid crystal display element Top view showing the shape of the sealing material formed in plural (three steps in this example) on the outer periphery of the circular substrate Partial top view for explaining the sealing method

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Transparent substrate 3 Liquid crystal 4 Sealing material 5 Spacer 6 Small liquid crystal display element area | region 7 Sealing material 7a Sealing 7b Sealing 8 Sealing material 8a Sealing 8b Sealing 9 Sealing material 9a Sealing 9b Sealing

Claims (3)

  A plurality of small liquid crystal display element regions are formed on a pair of mother substrates, and a sealant formed on the outer periphery of each small liquid crystal display element region without a spacer between pixel electrodes and a sealant formed on the outer periphery of the mother substrate A method for manufacturing a small-sized liquid crystal display element, comprising affixing and polishing at least one of the mother substrates.   2. The method of manufacturing a small liquid crystal display element according to claim 1, wherein a plurality of outer peripheral sealing materials for the mother substrate are formed and polished.   3. The method for manufacturing a small liquid crystal display element according to claim 1, wherein the pair of mother substrates is sealed with a positive pressure and polished.

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