KR100294683B1 - Method for forming alignment film of liquid crystal display - Google Patents

Method for forming alignment film of liquid crystal display Download PDF

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KR100294683B1
KR100294683B1 KR1019940004027A KR19940004027A KR100294683B1 KR 100294683 B1 KR100294683 B1 KR 100294683B1 KR 1019940004027 A KR1019940004027 A KR 1019940004027A KR 19940004027 A KR19940004027 A KR 19940004027A KR 100294683 B1 KR100294683 B1 KR 100294683B1
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alignment film
alignment
liquid crystal
photopolymer
crystal display
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KR1019940004027A
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KR950027457A (en
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신현호
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구본준, 론 위라하디락사
엘지.필립스 엘시디 주식회사
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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • G02F1/13378—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by treatment of the surface, e.g. embossing, rubbing or light irradiation
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/133509—Filters, e.g. light shielding masks
    • G02F1/133512—Light shielding layers, e.g. black matrix
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • G02F1/133753—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • G02F1/133753—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
    • G02F1/133761—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle with different pretilt angles

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  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Liquid Crystal (AREA)

Abstract

PURPOSE: An alignment film forming method for a liquid crystal display is provided to improve the optical characteristics such as viewing angle characteristics of the liquid crystal display device and simplify the forming of pixel dividing alignment film by using a photopolymer alignment film. CONSTITUTION: An alignment film forming method for a liquid crystal display includes the steps of evaporating and rubbing a nonorganic orientation agent on a substrate, coating a photopolymer alignment film on the nonorganic orientation agent, forming an orientation by radiating linear-polarized ultraviolet rays on the photopolymer alignment film by using an optical mask, and etching the photopolymer alignment film of which orientation is not formed.

Description

액정표시소자의 배향막 형성방법Method of forming alignment film of liquid crystal display device

제1도는 액정표시소자 제조에 있어서의 DD배향방법을 도시한 도면.1 is a view showing a DD alignment method in manufacturing a liquid crystal display device.

제2도는 종래의 DDTN패널과 TN패널의 시야각특성을 비교하여 나타낸 도면.2 is a view showing comparison of viewing angle characteristics of a conventional DDTN panel and a TN panel.

제3도는 선편광된 자외선 조사시간에 따른 굴절율 이방성의 변화를 나타낸 도면.3 is a view showing a change in refractive index anisotropy according to the linearly polarized ultraviolet irradiation time.

제4도는 본 발명의 액정표시소자 패널 구조도.4 is a structural diagram of a liquid crystal display device panel of the present invention.

본 발명은 액정표시소자의 배향막 형성방법에 관 한 것으로, 특히 광폴리머(Photopolymer)를 이용하여 간편한 방법에 의해 화소분할 배향막을 형성하는 방법에 관한 것이다.The present invention relates to a method of forming an alignment layer of a liquid crystal display device, and more particularly, to a method of forming a pixel split alignment layer by a simple method using a photopolymer.

액정표시소자의 제조에 있어서 넓은 시야각을 얻기 위해서 화소를 분할하여 배향하는 방법들이 몇가지 제안되었다.Several methods for dividing and orienting pixels in order to obtain a wide viewing angle in manufacturing a liquid crystal display device have been proposed.

이중에는 TD(Two Domain)배향, DD(Domain Divided)배향, 컴플리멘터리(complementary)배향등이 있는데, TD배향은 한 화소를 2개로 구분하여 각각 다른 방향으로 프리틸트(pretilt)각을 주는 방법이며, DD배향은 제1도에 도시한 바와 같이 프리틸트방향은 큰 프리틸트각에 의존함으로써 화소가 분할되는 방법이다. 그리고 컴플리멘터리배향은 상기 2가지의 배향방법을 모두 도입한 절충형이라 할 수 있다.Among these, TD (Two Domain) orientation, DD (Domain Divided) orientation, and complementary orientation are used. TD orientation divides one pixel into two and gives a pretilt angle in different directions. The DD orientation is a method in which pixels are divided by the pretilt direction depending on a large pretilt angle as shown in FIG. Complementary alignment can be said to be a compromise that introduces both orientation methods.

이들 방법들은 모두 액정표시소자의 시야각을 개선하는 방법으로 TN셀에서의 시야각은 콘트라스트비(contrast ratio)나 휘도에 영향을 미친다는 것은 잘 알려진 사실이다. 이중 특히 DD배향의 경우 제2도에 도시된 바와 같이 종래의 TN패널에 비해 시야각 특성이 크게 개선된 것을 볼 수 있다.All of these methods improve the viewing angle of the liquid crystal display, and it is well known that the viewing angle in the TN cell affects contrast ratio and luminance. In particular, in the case of the DD orientation, as shown in FIG. 2, the viewing angle characteristic is significantly improved compared to the conventional TN panel.

시야각 특성을 개선하기 위해 화소를 분할하여 배향하는 경우 모두가 복잡한 공정의 순서가 필요하고 특히 제2도에 도시된 DD배향의 경우 무기배향제의 증착(evaporation)→유기배향막 도포→감광성물질 도포→자외선 조사→현상(유기배향막의 부분제거)→스트립(남아 있는 감광성 물질제거)→유기배향막의 러빙등 많은 공정이 필요하여 셀이 오염될 수 있는 기회가 많아지는 문제가 있다.In order to improve the viewing angle characteristics, all of the pixels are divided and oriented, and a complicated sequence of steps is required. Particularly, in the case of the DD alignment shown in FIG. 2, evaporation of an inorganic alignment agent → application of an organic alignment layer → application of a photosensitive material → There are many problems such as ultraviolet irradiation → development (partial removal of organic alignment film) → strip (removal of remaining photosensitive material) → rubbing of organic alignment film, which increases the chance of cell contamination.

본 발명은 상술한 문제를 해결하기 위한 것으로, 광폴리머 배향막을 이용하여 공정의 수를 줄임으로써 보다 간편하게 화소분할 배향막을 형성하는 방법을 제공하는 것을 그 목적으로 한다.SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a method of forming a pixel-divided alignment film more easily by reducing the number of processes by using the photopolymer alignment film.

상기 목적을 달성하기 위한 본 발명의 액정표시소자의 배향막 형성방법은 기판에 무기배향제를 증착하여 러빙하는 공정과, 상기 무기배향제위에 광폴리머 배향막을 도포하는 공정, 광마스크를 이용하여 선 편광된 자외선을 상기 광폴리머 배향막에 조사하여 배향방향을 형성하는 공정과, 상기 배향처리되지 않은 광폴리머 배향막을 식각하는 공정을 포함하여 이루어진다.The alignment film forming method of the liquid crystal display device of the present invention for achieving the above object is a step of depositing and rubbing an inorganic alignment agent on a substrate, the process of applying a photopolymer alignment layer on the inorganic alignment agent, linearly polarized using a photomask And irradiating the ultraviolet rays to the photopolymer alignment layer to form an alignment direction, and etching the unaligned photopolymer alignment layer.

이하, 첨부된 도면을 참조하여 본 발명을 상세히 설명한다.Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

본 발명에서는 광폴리머 배향막을 이용한 화소분할 배향 액정표시소자에서 종래의 폴리이미드를 사용한 DD배향 TN보다 공정의 수를 대폭 줄임으로써 액정셀의 오염의 기회를 적게 하고 제조단가를 낮출 수 있는 방법을 제공한다.The present invention provides a method for reducing the manufacturing cost and reducing the manufacturing cost of the liquid crystal cell by significantly reducing the number of processes in the pixel-divided alignment liquid crystal display device using the photopolymer alignment layer than the DD alignment TN using the conventional polyimide. do.

폴리비닐플루오르 시나메이트(PVCN-F)에 선편광된 자외선을 조사하면 러빙없이 액정분사를 원하는 방향으로 평면구조로 배향할 수 있고 광폴리머 배향막의 표면에 조사되는 자외선의 강도(에너지)를 달리 해서 프리틸트각도를 조절할 수 있다.By irradiating polyvinyl fluorine cinnamate (PVCN-F) with linearly polarized ultraviolet rays, the liquid crystal spray can be oriented in a planar structure in a desired direction without rubbing, and it is free by changing the intensity (energy) of ultraviolet rays irradiated onto the surface of the photopolymer alignment layer You can adjust the tilt angle.

6mW/㎠의 강도를 가진 자외선을 글랜-톰슨(Glan-Thomson)프리즘 통과시킨 선 편광된 자외선을 광폴리머 배향막(PVCN-F)에 조사했을때 시간에 다른 굴절을 이방성(Δn)의 값을 제3도에 나타내었다. 굴절율 이방성의 포화영역(30분 이상)에 있는 기판과 불포화영역(30분 이하)에 있는 기판을 합착하여 셀을 만들 경우, 프리틸트각을 0-18° 정도 사이에서 조절할 수 있다.When the linearly polarized ultraviolet ray, which was passed through the Glan-Thomson prism with ultraviolet rays having an intensity of 6 mW / cm 2, was irradiated to the photopolymer alignment layer (PVCN-F), the refractive index was different from the time. 3 is shown. When the cell is formed by joining a substrate in a saturated region (30 minutes or more) with a refractive index anisotropy and a substrate in an unsaturated region (30 minutes or less), the pretilt angle can be adjusted between about 0-18 °.

이와 같이 광폴리머 배향막을 이용하면 배향막 자체에 러빙공정이 필요하지 않고 특히 화소분할 배향을 하는 경우 공정수를 줄일 수 있는 장점이 있다.As such, when the photopolymer alignment layer is used, a rubbing process is not required for the alignment layer itself, and in particular, the number of steps may be reduced when performing pixel-division alignment.

본 발명의 액정표시소자 배향막 형성방법은 다음과 같은 공정으로 이루어진다.The method for forming a liquid crystal display device alignment film of the present invention comprises the following steps.

무기배향막을 증착한 후, 러빙공정을 행하고 광폴리머 배향막을 도포한 다음 광마스크를 통한 선편광된 자외선을 조사한 다음 현상을 통해 광폴리머 배향막을 부분적으로 제거한다.After depositing the inorganic alignment layer, a rubbing process is performed, a photopolymer alignment layer is applied, and linearly polarized ultraviolet rays are irradiated through the photomask, and then the photopolymer alignment layer is partially removed through development.

이와 같이 형성된 액정표시소자 패널의 구조를 제4도에 나타내었다.The structure of the liquid crystal display panel thus formed is shown in FIG.

각 영역A와 영역B의 프리틸트의 방향은 높은 프리틸트각을 가지는 배향막에 의해 영향을 받게 된다. 이 경우, 각 영역사이에는 빛의 누설 현상(disclination)이 일어나는데 이것을 방지하기 위해 블랙매트릭스를 사용한다.The direction of the pretilt in each of the regions A and B is influenced by the alignment film having a high pretilt angle. In this case, light leakage occurs between each region, and a black matrix is used to prevent this.

이상 상술한 바와 같이 본 발명은 액정표시소자의 광학 특성, 특히 시야각 특성을 개선하기 위한 것으로서, 종래에 알려진 방법에 비해 공정수를 줄임으로써 액정셀의 오염기회를 줄일 수 있게 되고, 이에 따라 생산(제조)단가를 낮추는데 크게 기여할 수 있게 된다.As described above, the present invention is to improve the optical characteristics of the liquid crystal display device, in particular, the viewing angle characteristic, and by reducing the number of processes compared to the conventionally known method, it is possible to reduce the chance of contamination of the liquid crystal cell, thereby producing It can contribute greatly to lower the manufacturing cost.

Claims (5)

기판에 무기배향제를 증착하여 러빙하는 공정과, 상기 무기배향제 위에 광폴리머 배향막을 도포하는 공정과, 상기 광폴리머 배향막 위에 광마스크를 이용하여 선편광된 자외선을 조사하여 배향방향을 형성하는 공정과, 상기 배향처리되지 않은 광폴리머 배향막을 식각하는 공정을 포함하여 이루어지는 것을 특징으로 하는 액정표시소자의 배향막 형성방법.Depositing and rubbing an inorganic alignment agent on a substrate, applying a photopolymer alignment layer on the inorganic alignment agent, and irradiating linearly polarized ultraviolet rays using an optical mask on the photopolymer alignment layer to form an alignment direction; And etching the unpolymerized photopolymer alignment layer. 제1항에 있어서, 액정표시소자의 한 화소내의 광폴리머 배향막과 무기배향제 사이에 블랙매트릭스를 형성하는 공정이 더 포함되는 것을 특징으로 하는 액정표시소자의 배향막 형성방법.The method of claim 1, further comprising forming a black matrix between the photopolymer alignment film and the inorganic alignment agent in one pixel of the liquid crystal display device. 제1항에 있어서, 상기 배향처리된 광배향막과 상기 식각된 광배향막의 프리틸트각은 서로 다른 것을 특징으로 하는 액정표시소자의 배향막 형성방법.The method of claim 1, wherein the pretilt angles of the oriented photo alignment layer and the etched photo alignment layer are different from each other. 제1항에 있어서, 상기 배향처리된 광배향막과 상기 식각된 광배향막은 배향이 다른 영역으로 나뉘는 것을 특징으로 하는 액정표시소자의 배향막 형성방법.The method of claim 1, wherein the alignment-oriented photoalignment layer and the etched photoalignment layer are divided into regions having different alignments. 제4항에 있어서, 상기 영역 사이에 블랙매트릭스를 형성하는 것을 특징으로 하는 액정표시소자의 배향막 형성방법.The method of claim 4, wherein a black matrix is formed between the regions.
KR1019940004027A 1994-03-02 1994-03-02 Method for forming alignment film of liquid crystal display KR100294683B1 (en)

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KR1019940004027A KR100294683B1 (en) 1994-03-02 1994-03-02 Method for forming alignment film of liquid crystal display

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KR100716863B1 (en) * 2000-05-10 2007-05-09 주식회사 쉰들러 엘리베이터 Elevator governor which has emergency stopping device for up-down-direction

Citations (2)

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Publication number Priority date Publication date Assignee Title
KR910001437A (en) * 1989-06-28 1991-01-30 이헌조 LCD
JPH0651306A (en) * 1992-08-03 1994-02-25 Seiko Epson Corp Liquid crystal display element

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR910001437A (en) * 1989-06-28 1991-01-30 이헌조 LCD
JPH0651306A (en) * 1992-08-03 1994-02-25 Seiko Epson Corp Liquid crystal display element

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