KR20070034805A - Liquid crystal display - Google Patents

Abstract

Provided is a liquid crystal display device. The liquid crystal display device includes an upper substrate and a lower substrate bonded by a sealant layer. A color filter may be formed on the upper substrate, and a thin film transistor forming a pixel region may be formed on the lower substrate. The present invention is characterized in that a dummy pattern is formed at an edge of a substrate on which no pixel region is formed so that a predetermined gap is provided at edges of the upper substrate and the lower substrate. The gap may be maintained at the edges of the upper substrate and the lower substrate in the dummy pattern to prevent the edges of the upper and lower substrates from being narrowed when the upper substrate and the lower substrate are bonded to each other.

Liquid crystal, double gap, dummy pattern

Description

Liquid crystal display {LIQUID CRYSTAL DISPLAY}

1 is a plan view illustrating a conventional liquid crystal display device.

FIG. 2 is a cross-sectional view taken along the line II ′ of FIG. 1.

3 is a plan view illustrating a liquid crystal display according to a preferred embodiment of the present invention.

4 is a cross-sectional view taken along the line II-II 'of FIG.

The present invention relates to a liquid crystal display, and more particularly, to a liquid crystal display having a structure providing a gap between an upper substrate on which a color filter is formed and a lower substrate on which a thin film transistor is formed.

The liquid crystal display device includes a liquid crystal layer filled between a lower substrate, an upper substrate, and upper and lower substrates bonded to each other with a predetermined gap. In general, a pixel region having an active pixel structure in which data lines intersect is formed on the lower substrate, and a color filter corresponding to the pixel region is formed on the upper substrate.

1 is a plan view illustrating a liquid crystal display according to the related art, and FIG. 2 is a cross-sectional view taken along line II ′ of FIG. 1.

1 and 2, in the liquid crystal display, an upper substrate 10 having a color filter 14 and a lower substrate 12 having a pixel region (not shown) having an active pixel structure are bonded to each other. The liquid crystal layer is filled in the gap region between the upper substrate 10 and the lower substrate 12. The upper matrix 10 is formed with a black matrix 16 having an opening area corresponding to the pixel area, and the color filter 14 is formed on the opening area, respectively. The color filter 14 is formed corresponding to the pixel region, and an overcoat layer 18 is formed on the color filter 14 to protect the color filter 14.

The overcoat layer 18 may be patterned to form regions having different cell gaps in the pixel region. For example, in a transflective liquid crystal display having a pixel region divided into a reflective region and a transmissive region, a thick overcoat layer is formed on the reflective region and an overcoat layer is formed on the transmissive region in order to reduce the optical characteristic variation between the reflective region and the transmissive region. It may not be formed or may be formed relatively thin. A column spacer 20 is formed on the black matrix 16 between the color filter layers to provide a cell gap between the upper substrate 10 and the lower substrate 12.

A sealant layer 22 for bonding the upper substrate 10 and the lower substrate 12 along the edges of the upper substrate 10 and the lower substrate 12 is coated. Typically, the sealant layer 22 is applied along the edge of the lower substrate 12 by a printing technique or a dispensing technique, and liquid crystal is injected or dropped into the liquid crystal region defined by the sealant layer 22 to form upper and lower substrates. Liquid crystal is filled in between.

The upper substrate 10 and the lower substrate 12 constituting the liquid crystal display may be divided into portions in which patterns constituting the pixel region are formed and edge regions in which the patterns are not formed. An enlarged substrate when the sealant layer 22 is applied between the upper substrate 10 and the lower substrate 12 so that the upper substrate 10 and the lower substrate 12 are bonded by the sealant layer 22. The edges of the upper substrate 10 and the lower substrate 12 may be bonded to each other at the edges. In this case, the space between the upper and lower substrates 10 and 12 bonded to the sealant layer 22 is closed, so that air or gas discharge l1 is not desired. Bonding of the substrate 12 may not be uniform. As a result, the shape of the edge of the substrate of the large liquid crystal display may be distorted to cause various problems such as unevenness of the gap between the upper and lower substrates 12, poor compression of the sealant, and generation of bubbles. In particular, since the cell gap of the semi-transmissive liquid crystal display device is about 1.7 μm, the gas discharge defect due to the shape distortion of the substrate may become more severe as the liquid crystal display device becomes larger.

An object of the present invention is to provide a liquid crystal display device having a structure that can prevent the shape distortion of the substrate due to the narrowing of the edge portion of the substrate when the upper substrate and the lower substrate are bonded.

Another object of the present invention is to provide a liquid crystal display device having a predetermined gap guaranteed between an upper substrate and a lower substrate constituting the liquid crystal display device.

In order to achieve the above technical problem, the present invention provides a liquid crystal display device in which a dummy pattern is formed at an edge of a substrate on which no pixel region is formed, and a predetermined gap is provided at edges of an upper substrate and a lower substrate. The liquid crystal display device includes an upper substrate and a lower substrate bonded by a sealant layer. A color filter may be formed on the upper substrate, and a thin film transistor forming a pixel region may be formed on the lower substrate.

The present invention is characterized in that the dummy pattern is formed on the edge of the upper substrate. The dummy pattern may provide a gap between the upper substrate and the lower substrate, and the sealant layer may be applied to overlap the dummy pattern to bond the upper substrate and the lower substrate.

In one embodiment of the present invention, a black matrix having a plurality of opening regions may be formed on the upper substrate, and a plurality of color filters may be formed on the opening region of the black matrix. An overcoat layer may be formed on the color filter to protect the color filter and to form a cell gap having a step in the pixel area. A column spacer is formed on the black matrix that provides a cell gap between the upper substrate and the lower substrate.

The dummy pattern may have a structure in which the layers forming the black matrix, the color filter, the overcoat layer, and the column spacer are stacked. In addition, the dummy pattern may be formed at the edge of the upper substrate in a line shape. Preferably, the dummy pattern may be formed at long edges of the upper substrate and the lower substrate. The sealant layer may be applied along edges of the upper substrate and the lower substrate, and a sealant layer overlapping the dummy pattern may be applied on the dummy pattern in parallel with the dummy pattern.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed subject matter is thorough and complete, and that the spirit of the present invention to those skilled in the art will fully convey. In the drawings, the thicknesses of layers and regions are exaggerated for clarity. In addition, where a layer is said to be "on" another layer or substrate, it may be formed directly on the other layer or substrate, or a third layer may be interposed therebetween. Portions denoted by like reference numerals denote like elements throughout the specification.

3 is a plan view illustrating a liquid crystal display according to a preferred embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line II-II 'of FIG. 3.

Referring to FIGS. 3 and 4, in the liquid crystal display, the upper substrate 50 and the lower substrate 52 are bonded to each other and filled in the gap between the upper substrate 50 and the lower substrate 52. It consists of liquid crystals. In general, a color filter 54 corresponding to a pixel region is formed on the upper substrate 50, and a black matrix 56 formed between the color filters 54 and partitioning a plurality of pixel regions includes the upper substrate ( 50). The black matrix 56 has an opening area corresponding to the pixel, and the color filters 54 are formed in the opening area of the black matrix 56, respectively. An overcoat layer 58 is formed on the upper substrate 52 on which the color filter 54 is formed. The overcoat layer 58 may be evenly coated on the upper substrate 50 on which the color filter 54 is formed, or may be patterned to reduce the variation in optical characteristics of the transmission region and the reflection region in the transflective liquid crystal display. have. The pixel region of the transflective liquid crystal display is divided into a reflective region and a transmissive region, and the cell gap t1 of the transmissive region is preferably two times the cell gap t2 of the reflective region. Thus, the overcoat layer 58 may be formed on the color filter of the reflective region and patterned in the transmissive region. The common electrode is formed on the upper substrate 50 on which the overcoat layer 58 is formed.

Word lines and data lines that cross each other are formed on the lower substrate, and pixel regions of an active pixel structure in which a plurality of thin film transistors are connected to the word lines and data lines are formed. In the present invention, the pixel area formed on the lower substrate may be selected from various known planar structures and cross-sectional structures.

The liquid crystal display device is formed by bonding large substrates to each other. In this case, the upper substrate 50 and the lower substrate 52 may be bent by tension, so that the cell gap of the pixel region filled with the liquid crystal may not be maintained. In order to maintain a cell gap in front of the display device, a particulate spacer may be applied between the upper substrate 50 and the lower substrate 52, or the column spacer 60 may be formed on the black matrix 56 as illustrated. Can be. The column spacer 60 provides a constant cell gap between the upper substrate 50 and the lower substrate 52.

In the upper substrate 50 of the liquid crystal display according to the present invention, a dummy pattern 80 is formed at an edge portion where no pixel region is formed. The dummy pattern 80 has a structure in which a material layer forming a black matrix 56, a color filter 54, an overcoat layer 58, and a column spacer 60 formed on an upper substrate corresponding to a pixel area is stacked. Has The dummy pattern 80 overlaps the sealant layer 62 for bonding the upper substrate 50 and the lower substrate 52 when the upper substrate 50 and the lower substrate 52 are bonded to each other. The upper substrate 50 and the lower substrate 52 are prevented from being narrowed at the edge of the substrate of the liquid crystal display. The dummy pattern 80 may have a portion where two substrates are easily constricted when the upper substrate 50 and the lower substrate 52 of the liquid crystal display are bonded together. For example, the dummy pattern 80 may be formed at an edge portion of a long side of a substrate of a liquid crystal display having long sides and short sides, and may be formed in a line shape parallel to the long side.

A sealant layer 62 is formed between the upper substrate 50 and the edge of the lower substrate 52 to bond the upper substrate 50 and the lower substrate 52 to hold the liquid crystal filled in the pixel area. Is applied. In general, the sealant layer is printed along the edge of the lower substrate 52 or dispensed to have a shape surrounding the display area of the liquid crystal display. In the present invention, the sealant layer 62 is applied to overlap the dummy pattern 80 which provides a gap at the edges of the upper substrate 50 and the lower substrate 52 so as to overlap the upper substrate 50 and the lower portion at the edge. The gap of the substrate 52 is increased. The sealant layer 62 may be applied to overlap the dummy pattern in parallel with the dummy pattern 80. Therefore, when the upper substrate 50 and the lower substrate 52 are aligned so that the upper and lower substrates 50 and 52 are bonded to each other, the edge portions of the upper and lower substrates 50 and 52 are narrowed. To prevent vapors, such as solvents contained in the sealant, and air and gas flow l 2. As a result, when the dummy pattern 80 is interposed at the edges of the upper and lower substrates 50 and 52, when the upper and lower substrates 50 and 52 are bonded to each other, an outer side of the sealant layer 62 is formed. The upper and lower substrates 50 and 52 may be opened to uniformly bond the upper and lower substrates 50 and 52.

As described above, according to the present invention, a gap between the upper substrate and the lower substrate is maintained by the dummy pattern formed at the edge of the substrate for manufacturing the liquid crystal display so that the gap is maintained at the edges of the upper substrate and the lower substrate. It can prevent the edges from narrowing.

According to the present invention, the edges of the upper and lower substrates can be prevented from being narrowed so that the flow of air or gas can be smoothed when the upper and lower substrates are bonded. It is possible to prevent the shape of the distortion.

Claims (5)

A liquid crystal display device in which an upper substrate on which a color filter is formed and a lower substrate on which a thin film transistor are formed are bonded by a sealant layer. And a dummy pattern formed at an edge of the liquid crystal display device to provide a gap between the upper substrate and the lower substrate, wherein the sealant layer is applied to overlap the dummy pattern so that the upper substrate and the lower substrate are bonded to each other. A liquid crystal display device, characterized in that. The method according to claim 1, A black matrix formed on the upper substrate and having a plurality of opening regions; A plurality of color filters respectively formed on the opening area of the black matrix; An overcoat layer formed on the color filter; And A column spacer formed on the black matrix and providing a cell gap between the upper substrate and the lower substrate; The dummy pattern has a structure in which the layers forming the black matrix, the color filter, the overcoat layer, and the column spacer are stacked. The method according to claim 1 or 2, And the dummy pattern is formed at an edge of the upper substrate in a line shape. The method according to claim 3, And the sealant layer is applied along edges of the upper substrate and the lower substrate, and a sealant layer overlapping the dummy pattern is coated on the dummy pattern in parallel with the dummy pattern. The method according to claim 3, And the dummy pattern is formed at a long side edge of the upper substrate.

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