KR20050000177A - Liquid Crystal Display Panel and Fabricating Method Thereof - Google Patents

Abstract

PURPOSE: An LCD(Liquid Crystal Display) panel and a method for manufacturing the LCD panel are provided to prevent a substrate from being warped by absorbing load applied to the substrate and a black matrix using a planarization layer, to thereby improve luminance of the LCD panel. CONSTITUTION: An LCD panel includes a black matrix(102) formed on a substrate(101), a color filter(106) formed on the substrate on which the black matrix is formed, and a planarization layer(107) formed on the substrate on which the color filter is formed. The planarization layer includes an elastic resin, a cross linking agent and a plurality of acrylic monomers to planarize the substrate.

Description

Liquid Crystal Display Panel and Fabrication Method Thereof}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel, and more particularly, to a liquid crystal display panel capable of improving luminance and a method of manufacturing the same.

In general, a liquid crystal display (LCD) displays an image corresponding to a video signal on a liquid crystal display panel in which liquid crystal cells are arranged in a matrix form by adjusting light transmittance of liquid crystal cells according to a video signal. To this end, the liquid crystal display device includes a liquid crystal display panel in which liquid crystal cells are arranged in an active matrix form, and driving circuits for driving the liquid crystal display panel.

The liquid crystal display is roughly classified into a twisted nematic (TN) mode and an in plan switch (IPS) mode using a vertical electric field according to the electric field driving the liquid crystal.

The TN mode is a mode in which a liquid crystal is driven by a vertical electric field between a pixel electrode and a common electrode disposed to face the upper substrate. The TN mode has a large aperture ratio and a narrow viewing angle.

The IPS mode is a mode in which a liquid crystal is driven by a horizontal electric field between a pixel electrode and a common electrode disposed side by side on a lower substrate, and has a large viewing angle, but a small aperture ratio.

1 is a cross-sectional view showing a liquid crystal display panel of a conventional IPS mode.

In the liquid crystal display panel illustrated in FIG. 1, a black matrix 2, a color filter 6, sequentially formed on an upper substrate 1 having a transparent electrode material (not shown) to prevent static electricity or the like on the rear surface thereof. An upper plate composed of the planarization layer 7, the spacer 13, and the upper alignment layer 8, a thin film transistor (not shown) formed on the lower substrate 5, the common electrode 4, the pixel electrode 9, and the like. A lower plate composed of the lower alignment layer 10 and a liquid crystal (not shown) injected into an inner space between the upper plate and the lower plate are provided.

In the upper plate, the black matrix 2 is formed to overlap the TFT region of the lower substrate 5 and the region of the gate lines and data lines (not shown) and partitions a cell region in which the color filter 6 is to be formed.

The black matrix 2 prevents light leakage and absorbs external light to enhance contrast.

The color filter 6 is formed over the cell region separated by the black matrix 2 and the black matrix 2. The color filter 6 is formed for each of R, G, and B to implement R, G, and B colors.

The planarization layer 7 is formed to cover the color filter to planarize the upper substrate 1.

The spacer 13 maintains a cell gap between the upper substrate 1 and the lower substrate 5.

In the lower plate, the TFT 17 overlaps the gate electrode 16 formed on the lower substrate 5 together with the gate line (not shown), with the gate electrode 16 and the gate insulating film 129 interposed therebetween. And a source / drain electrodes 128 and 130 formed together with a data line (not shown) with the semiconductor layer 126 interposed therebetween.

The TFT 17 supplies a pixel signal from the data line to the pixel electrode 9 in response to a scan signal from the gate line. The pixel electrode 9 is a transparent conductive material having a high light transmittance and is in contact with the drain electrode 130 of the TFT 17 with the protective film 108 interposed therebetween. The common electrode 4 is formed in a stripe shape so as to alternate with the pixel electrode 9.

The common electrode 4 is supplied with a common voltage which is a reference when driving the liquid crystal. The liquid crystal rotates with respect to the horizontal direction by the horizontal electric field between the common voltage and the pixel voltage supplied to the pixel electrode 9.

The upper and lower alignment layers 8 and 10 for liquid crystal alignment are formed by applying an alignment material such as polyimide and then performing a rubbing process.

2A to 2F are cross-sectional views illustrating a method of manufacturing a top plate of a conventional IPS mode step by step.

First, an opaque material such as an opaque metal or an opaque resin is deposited on the upper substrate 1, and then the opaque material is patterned by an etch process and a photolithography process using a first mask. ) Is formed.

After the red resin R is deposited on the upper substrate on which the black matrix 2 is formed, the red resin R is patterned by a photolithography process and an etching process using a second mask, thereby providing red color as shown in FIG. 2B. The color filter 3R is formed.

After the green resin G is deposited on the upper substrate 1 on which the red color filter 3R is formed, the green resin G is patterned by a photolithography process and an etching process using a third mask, as shown in FIG. 2C. As shown, the green color filter 3G is formed.

After the blue resin B is deposited on the upper substrate 1 on which the green color filter 3G is formed, the blue resin B is patterned by a photolithography process and an etching process using a fourth mask, as shown in FIG. 2D. As shown, the blue color filter 3B is formed.

The planarization layer 7 is formed as shown in FIG. 2E by depositing a photocurable planarization material on the upper substrate 1 on which the red, green, and blue color filters 6 are formed by spin coating or the like.

Here, the planarization material is formed by mixing an organic resin having a molecular structure as shown in FIG. 3A, a plurality of acrylic monomers having a molecular structure as shown in FIG. 3B, and a photoinitiator (or photoinitiator).

Compositions included in this planarization material have a composition as shown in Table 1 below.

Composition Organic resin Acrylic monomer Photoinitiator Furtherance 40-45% 40-45% 10-20%

Such a planarization material having a composition is deposited on a substrate and then fired by a firing process to form a planarization layer 7 having a rigid chain structure as shown in FIG. 3C.

A spacer 13 formed of a highly elastic material is formed on the upper substrate 1 on which the planarization layer 7 is formed, as shown in FIG. 2F.

Meanwhile, a part of the load applied to the spacer 13 during the bonding process of the upper substrate 1 having the color filter array and the lower substrate 5 having the thin film transistor array is absorbed by the spacer 13. But. Part of the load not absorbed by the spacer 13 is transmitted to the planarization layer 7. The planarization layer 7 has the advantage that the molecular structure is uniformly spaced between molecules and has a uniform transmittance as a solid chain structure, but the elastic deformation is difficult due to the rigid structure. In addition, the molecular structure of the black matrix 2 is also difficult to elastically elastic with a chain structure.

As a result, the load applied to the planarization layer 7 is transferred to the black matrix 2 and the upper substrate 1 so that the planarization layer 7 and the black at the portion corresponding to the spacer 13 are shown in FIG. 4. The matrix 2 and the upper substrate 1 are bent due to plastic deformation and, in severe cases, breakage occurs.

The flattening layer 7, the black matrix 2 and the upper substrate 1 are bent or broken due to the problem of uneven brightness.

Accordingly, an object of the present invention is to provide a liquid crystal display panel and a method of manufacturing the same that can improve the brightness.

1 is a cross-sectional view showing a liquid crystal display panel of the conventional IPS mode.

2A to 2F are cross-sectional views illustrating a method of manufacturing a top plate of a conventional liquid crystal display panel in stages.

3a to 3c are views for explaining the composition of the planarization layer shown in FIG.

4 is a view showing that the planarization layer, the black matrix, and the upper substrate shown in FIG. 1 are bent under load.

5 is a cross-sectional view illustrating a liquid crystal display panel in IPS mode according to an embodiment of the present invention.

6a to 6c are views for explaining the composition of the planarization layer shown in FIG.

7A to 7F are cross-sectional views illustrating a method of manufacturing a top plate of the liquid crystal display panel shown in FIG.

<Explanation of symbols for the main parts of the drawings>

1,101: upper substrate 2,102: black matrix

4: common electrode 5,105: lower substrate

6,166 color filter 8,10 alignment film

16: gate electrode 7,107: planarization layer

13,113: spacer 128: source electrode

130: drain electrode 126: active layer

127: ohmic contact layer

In order to achieve the above object, a liquid crystal display panel according to an embodiment of the present invention comprises a black matrix formed on a substrate; A color filter formed on the substrate on which the black matrix is formed; And a planarization layer including an elastic resin and a crosslinking agent to planarize the substrate on the substrate on which the color filter is formed.

The planarization layer is characterized in that it comprises 40 to 45% of the elastic resin, 40 to 45% of a plurality of acrylic monomers and 10 to 20% of the crosslinking agent.

The molecular structure of the planarization layer is characterized in that the layered structure.

It further comprises a spacer formed on the planarization layer.

A method of manufacturing a liquid crystal display panel according to an embodiment of the present invention includes forming a black matrix on a substrate; Forming a color filter on the substrate on which the black matrix is formed; And forming a planarization layer including an elastic resin and a crosslinking agent on the substrate on which the color filter is formed.

The planarization layer is characterized in that it comprises 40 to 45% of the elastic resin, 40 to 45% of a plurality of acrylic monomer and 10 to 20% of the crosslinking agent.

And forming a spacer on the planarization layer.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 5 to 7.

5 is a cross-sectional view illustrating a liquid crystal display panel in an IPS mode according to an embodiment of the present invention.

In the liquid crystal display panel illustrated in FIG. 5, the black matrix 102, the color filter 106, which are sequentially formed on the upper substrate 101 having a transparent electrode material (not shown) to prevent static electricity or the like on the rear surface thereof. An upper plate on which a color filter array including a planarization layer 107, a spacer 113, and an upper alignment layer (not shown) is formed, and a thin film transistor, a common electrode, a pixel electrode, and a lower alignment layer on the lower substrate 105. A lower plate on which a thin film transistor array (not shown) is formed, and a liquid crystal (not shown) injected into an inner space between the upper plate and the lower plate is provided.

In the upper plate, the black matrix 102 is formed to overlap the TFT region of the lower substrate 105 and the gate line and data line regions (not shown) and partitions a cell region in which the color filter 106 is to be formed.

The black matrix 102 prevents light leakage and absorbs external light to increase contrast. The color filter 106 is formed over the cell region and the black matrix 102 separated by the black matrix 102.

The color filter 106 is formed for each of R, G, and B to implement R, G, and B colors. The planarization layer 107 is formed to cover the color filter to planarize the upper substrate 101. The spacer 113 serves to maintain a cell gap between the upper substrate 101 and the lower substrate 105.

In the planarization layer of the liquid crystal display panel according to the present invention, an organic resin having a molecular structure as shown in FIG. 6A and a planarization material mixed with a plurality of acrylic monomers having a molecular structure as shown in FIG. 6B and a crosslinking agent are formed on a substrate. It is formed by depositing by spin coating or the like and then firing by firing.

Compositions included in this planarization material have a composition as shown in Table 2 below.

Composition Elastic resin Acrylic monomer Crosslinking agent Furtherance 40-45% 40-45% 10-20%

The molecular structure of the planarization layer 107 formed using the planarization material having such a composition has a layered molecular structure having a lower density than the conventional chain structure as shown in FIG. 6C.

The planarization layer 107 having the layered molecular structure is not absorbed by the spacer 113 during the bonding process of the upper substrate 101 on which the color filter array of the liquid crystal display panel is formed and the lower substrate 105 on which the thin film transistor array is formed. Elastic deformation to absorb part of the load.

That is, some of the load applied to the spacer 113 during the bonding process of the upper substrate 101 and the lower substrate 105 are absorbed by the spacer 113 and the part of the load not absorbed by the spacer is the flattening layer 107. ) Is absorbed by the planarization layer 107 by elastic deformation.

As such, the planarization layer 107 absorbs a part of load so that the load is not transmitted to the black matrix 102 and the upper substrate 101.

As such, the flattening layer 107 of the liquid crystal display panel according to the present invention can prevent the load from being transferred to the black matrix 102 and the upper substrate 101 by absorbing the load not absorbed by the spacer 113. . As a result, the bending of the black matrix 102 and the upper substrate 101 is prevented, thereby improving luminance.

7A to 7F are cross-sectional views illustrating a method of manufacturing a top plate of a conventional IPS mode step by step.

First, an opaque material such as an opaque metal or an opaque resin is deposited on the upper substrate 101, and then the opaque material is patterned by an etch process and a photolithography process using a first mask. As shown in FIG. 7A, the black matrix 102 is formed. ) Is formed.

After the red resin R is deposited on the upper substrate on which the black matrix 102 is formed, the red resin R is patterned by a photolithography process and an etching process using a second mask, thereby redding the red resin as shown in FIG. 7B. The color filter 3R is formed.

After the green resin G is deposited on the upper substrate 101 on which the red color filter 3R is formed, the green resin G is patterned by an photolithography process and an etching process using a third mask, as shown in FIG. 7C. As shown, the green color filter 3G is formed.

After the blue resin B is deposited on the upper substrate 1 on which the green color filter 3G is formed, the blue resin B is patterned by a photolithography process and an etching process using a fourth mask, and thus shown in FIG. 7D. As shown, the blue color filter 3B is formed.

On the upper substrate 101 on which the red, green, and blue color filters 106 are formed, a planarization material including 40 to 45% of an elastic paper, 40 to 45% of a plurality of acrylic monomers and 10 to 20% of a crosslinking agent is formed. By depositing by spin coating or the like, the planarization layer 107 is formed as shown in FIG. 7E.

A spacer 113 formed of a high elastic material is formed on the upper substrate 101 on which the planarization layer 107 is formed, as shown in FIG. 7F.

As described above, the flattening layer capable of absorbing the load by elastic deformation is not only easy for the liquid crystal display panel of IPS (In plan Switch) mode but also to the liquid crystal display panel of TN (Twisted Nematic) mode and VA (Vertical Alignment) mode. Can be applied.

As described above, the flattening layer of the liquid crystal display panel and the manufacturing method of the liquid crystal display panel using the same according to the present invention form a liquid crystal display panel using a flattening layer capable of absorbing load by elastic deformation. As a result, the loads applied to the substrate and the black matrix are absorbed by the planarization layer, thereby preventing the substrate from being warped, thereby improving luminance.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (7)

A black matrix formed on the substrate; A color filter formed on the substrate on which the black matrix is formed; And a planarization layer including an elastic resin and a crosslinking agent to planarize the substrate on the substrate on which the color filter is formed. The method of claim 1, And the planarization layer comprises 40 to 45% of an elastic resin, 40 to 45% of a plurality of acrylic monomers, and 10 to 20% of a crosslinking agent. The method of claim 1, The molecular structure of the planarization layer is a liquid crystal display panel, characterized in that the layered structure. The method of claim 1, And a spacer formed on the planarization layer. Forming a black matrix on the substrate; Forming a color filter on the substrate on which the black matrix is formed; And forming a planarization layer including an elastic resin and a crosslinking agent on the substrate on which the color filter is formed. The method of claim 5, wherein The planarization layer is a manufacturing method of a liquid crystal display panel comprising 40 to 45% of the elastic resin, 40 to 45% of a plurality of acrylic monomers and 10 to 20% of the crosslinking agent. The method of claim 5, wherein And forming a spacer on the planarization layer.