KR20010056719A - Compensation Method of color and luminance along viewing angle for reflective polarizer - Google Patents

Compensation Method of color and luminance along viewing angle for reflective polarizer Download PDF

Info

Publication number
KR20010056719A
KR20010056719A KR1019990058305A KR19990058305A KR20010056719A KR 20010056719 A KR20010056719 A KR 20010056719A KR 1019990058305 A KR1019990058305 A KR 1019990058305A KR 19990058305 A KR19990058305 A KR 19990058305A KR 20010056719 A KR20010056719 A KR 20010056719A
Authority
KR
South Korea
Prior art keywords
film
liquid crystal
viewing angle
polarizing plate
alignment
Prior art date
Application number
KR1019990058305A
Other languages
Korean (ko)
Inventor
류기한
김성태
김인선
황희남
김양국
Original Assignee
권문구
엘지전선 주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 권문구, 엘지전선 주식회사 filed Critical 권문구
Priority to KR1019990058305A priority Critical patent/KR20010056719A/en
Publication of KR20010056719A publication Critical patent/KR20010056719A/en

Links

Classifications

    • 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
    • G02F1/133528—Polarisers
    • G02F1/133536—Reflective polarizers
    • 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
    • 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
    • G02F1/133528—Polarisers
    • G02F1/133543—Cholesteric polarisers

Landscapes

  • 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)
  • Polarising Elements (AREA)
  • Liquid Crystal (AREA)

Abstract

PURPOSE: A method of compensating phase shift and brightness according to viewing angle of reflective polarizer improves the phase shift and the brightness according to the viewing angle of a reflective cholesteric liquid crystal polarizer using a liquid crystal film homeotropically aligned by using an alignment layer. CONSTITUTION: An optical alignment layer has a carbon-carbon triple bond and a carbon-carbon double bond as a photoreaction-functional group. A homeotropically-aligned film is manufactured by fixing the alignment state through the light irradiation after a thermosetting nematic liquid crystal is homeotropically aligned by using the alignment layer. Exactly, an optical alignment material is dissolved in an organic solvent of MEK, THF and toluene then this solution is thinly coated on a plastic of PET, PC and TAC by using a roll coating method. The coated film passes through a dryer to remove the solvent, then it is irradiated by using a UV irradiator or is rewound without irradiating with UV ray. A hypergolic nematic liquid crystal is irradiated with the UV ray after it is coated on the film and dried, Therefore, the homeotropically-aligned film is formed by fixing the homeotropically aligned state after the curing process.

Description

반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법{Compensation Method of color and luminance along viewing angle for reflective polarizer}Compensation method of color and luminance along viewing angle for reflective polarizer}

본 발명은 수직 배향된 액정 필름을 이용한 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법에 관한 것이다.The present invention relates to a color difference and luminance compensation method according to a viewing angle of a reflective polarizer using a vertically aligned liquid crystal film.

일반적으로 네마틱액정을 수직배향시켜 제작한 수직배향(homeotropic) 필름은 양복굴절(positive birefringence) 특성을 나타내므로 콜레스테릭 액정(CLC) 필름과 음복굴절(negative birefringence) 특성을 갖는 필름의 각도에 따른 색차(color shift) 및 휘도(brightness)를 보상해줌으로써, 액정표시장치(liquid crystal display, 이하 LCD라 칭함)의 시야각 특성을 개선시키는 보상 필름이나 광학부품(optical component)으로서 이용할 수 있다.In general, homeotropic films produced by vertically aligning nematic liquid crystals exhibit positive birefringence characteristics, so the cholesteric liquid crystal (CLC) film and the film having negative birefringence characteristics are used at an angle. By compensating for color shift and brightness, the film can be used as a compensation film or an optical component for improving the viewing angle characteristic of a liquid crystal display (hereinafter referred to as LCD).

지금까지는 네마틱액정을 수직배향시키기 위해 인듐 산화주석(Indium Tin Oxide, 이하 ITO라 칭함)이 코팅된 유리 셀(glass cell)에 액정을 주입시키고 전기장이나 자기장을 부여하는 방법을 이용하였으나, 이러한 방법들은 다음과 같은 단점들을 가지고 있다.Until now, in order to vertically align nematic liquid crystals, a method of injecting a liquid crystal into a glass cell coated with indium tin oxide (ITO) and applying an electric or magnetic field has been used. Have the following disadvantages:

첫째 대면적 필름을 제조하기가 어렵고, 둘째 유리판(glass)에 상기 ITO를 코팅하고 두께조절을 위한 스페이서(spacer)를 분산시켜 렌즈를 합착한 후 액정을 주입해야 하는 등 공정이 복잡하며, 셋째 사용하는 액정물질의 점도가 높은 경우에는 주입이 어려워 사용하기 어렵다.First, it is difficult to manufacture a large-area film, and secondly, the process is complicated, such as coating the ITO on a glass plate and dispersing a spacer for thickness control, integrating a lens, and then injecting a liquid crystal. When the viscosity of the liquid crystal material is high, injection is difficult and difficult to use.

따라서, 이와 같은 방법으로는 두께 균일성이 확보된 대면적 필름을 제조하는 것은 불가능하다.Therefore, it is impossible to manufacture a large area film with a thickness uniformity by such a method.

현재 상기 LCD는 대형화 추세에 있으며, 대형 LCD에서는 작동 모드(mode)에 따라 시야각 특성을 개선시키는 보상필름이 필수적으로 요구되고 있고, 상기 양 복굴절(positive birefringence) 특성을 나타내는 수직배향(homeotropic) 필름이 이용될 수 있다.At present, LCDs are becoming larger in size, and large LCDs require a compensation film to improve viewing angle characteristics according to an operation mode, and a homeotropic film exhibiting positive birefringence characteristics is required. Can be used.

기존의 방법은 J. Appl. Phys, 81, 1962(1997), Appl. Phys. Lett, 73, 470(1998), Appl. Phys. Lett, 68, 2819(1996), Appl. Phys. Lett., 22, 386(1973) 자국성(homeotropic) 필름의 제조방법에 대해 기술하고 있다.The existing method is described in J. Appl. Phys, 81, 1962 (1997), Appl. Phys. Lett, 73, 470 (1998), Appl. Phys. Lett, 68, 2819 (1996), Appl. Phys. Lett., 22, 386 (1973) describes a method for producing a homeotropic film.

종래의 기술에 의하면 상기 ITO가 도포된 유리판(glass) 사이에 네마틱 액정 물질을 삽입한 후, 전기장을 부여하여 수직배향을 시키거나, 레시틴(lecithin),DMOAP(dimethyl-octadecyl-3-aminopropyl trimethoxysilyl chloride) 등과 같은 배향물질을 유리판 위에 스핀 코팅(spin coating) 등의 방법을 사용하여 박막 도포한 후 네마틱 액정물질을 이 위에 도포하여 수직배향을 구현하였다.According to the prior art, the nematic liquid crystal material is inserted between the glass coated with ITO, and an electric field is applied to the vertical alignment, or lecithin, DMOAP (dimethyl-octadecyl-3-aminopropyl trimethoxysilyl). A thin film was applied to the alignment material such as chloride) on the glass plate by spin coating, and then a nematic liquid crystal material was applied on the glass plate to realize vertical alignment.

그러나, 상기 ITO가 도포된 유리판을 이용하는 방법은 대면적 필름을 제조하기 어렵고, 유리판에 ITO를 코팅하고 두께조절을 위한 스페이서를 분산시켜 유리판을 합착한 후 액정을 주입해야 하는 등 공정이 복잡하며, 사용하는 액정물질의 점도가 높은 경우에는 주입이 어려워 사용하기 어렵다는 단점을 가지고 있다.However, the method using the glass plate coated with ITO is difficult to manufacture a large-area film, and the process is complicated, such as coating the ITO on the glass plate and dispersing the spacers for thickness control, bonding the glass plate, and then injecting the liquid crystal. When the viscosity of the liquid crystal material to be used is high, the injection is difficult to use has a disadvantage.

한편, 상기 레시틴이나 DMOAP와 같은 배향물질은 극성을 갖는 말단 관능기가 유리판 표면에 위치하고 길이가 알킬(alkyl) 관능기가 유리판 표면에 수직으로 배향됨에 의해 이 위에 도포되는 네마틱 액정을 수직배향시키는 것으로 알려져 있다.On the other hand, the alignment material such as lecithin or DMOAP is known to vertically align the nematic liquid crystals applied thereon by having a polar terminal functional group on the surface of the glass plate and an alkyl functional group of the length perpendicular to the surface of the glass plate. have.

따라서, 기판(substrate)이 유리가 아닌 PET와 같은 플라스틱(plastic)인 경우에는 적용할 수 없으므로 연속공정에 의해 대면적 필름을 제조할 수 없다는 단점이 있다.Therefore, the substrate (substrate) is not a glass (plastic), such as PET (plastic) is not applicable, there is a disadvantage that can not be produced a large area film by a continuous process.

기존의 광배향법은 액정의 배향방향과 프리틸트 각도를 자유롭게 조절할 수 있는 차세대 배향방법으로, 광배향물질이 도포된 기판에 선형 편광된(linearly polarized) 자외선을 조사하여 배향막에 배향력을 부여하는 방법이다. 이때 배향방향은 조사된 자외선의 입사방향에 의해, 그리고 프리틸트각은 조사 에너지에 의해 달라진다.Conventional photo-alignment method is a next-generation alignment method that can freely adjust the alignment direction and the pretilt angle of the liquid crystal, and applies alignment force to the alignment layer by irradiating linearly polarized ultraviolet rays on the substrate coated with the photo-alignment material. Way. At this time, the orientation direction is changed by the incident direction of irradiated ultraviolet rays, and the pretilt angle is changed by the irradiation energy.

상기 단점을 해결하기 위해 본 발명은, 배향막을 사용하여 수직 배향시킨 액정 필름을 제작하였으며, 이것을 이용해 콜레스테릭 액정 편광판의 시야각에 따른 색차 및 휘도의 개선 방법을 제공하는 것을 목적으로 한다.In order to solve the above disadvantages, the present invention has produced a liquid crystal film vertically aligned using an alignment film, and an object thereof is to provide a method for improving color difference and luminance according to the viewing angle of the cholesteric liquid crystal polarizing plate.

상기 목적을 달성하기 위해 본 발명은, 새로운 배향막을 사용하여 경화성 네마틱 액정을 수직배향시킨 후 광조사에 의해 배향상태를 고정시켜 수직 배향된 필름을 제조하는 제 1 과정, 상기 제조된 수직배향 필름을 이용하여 반사형 콜레스테릭 액정 편광판의 시야각에 따른 색차 및 휘도를 개선하는 제 2 과정을 포함하는 것을 특징으로 한다.In order to achieve the above object, the present invention is a vertical alignment of the curable nematic liquid crystal using a new alignment film, and then fixing the alignment state by light irradiation to manufacture a vertically aligned film, the prepared vertical alignment film It is characterized in that it comprises a second process for improving the color difference and the luminance according to the viewing angle of the reflective cholesteric liquid crystal polarizing plate using.

본 발명에 사용된 광배향막은 고분자 물질로서 탄소-탄소 삼중결합(carbon-carbon triple bond) 또는 탄소-탄소 이중결합(carbon-carbon double bond)을 광반응 관능기로 가지고 있다.The photoalignment film used in the present invention has a carbon-carbon triple bond or a carbon-carbon double bond as a polymer material as a photoreactive functional group.

이때 고분자 주사슬로는 폴리아크릴레이트(polyacrylate), 폴리실록산(polysiloxane), 폴리메타크릴레이트(polymethacrylate), 폴리사카라이드(polysaccharide), 폴리비닐 알코올(polyvinyl alcohol) 등을 사용하며, 고분자 주사슬과 광 반응부는 에스테르(ester) 또는 에테르(ether) 결합으로 연결되어 있다.At this time, the polymer main chain is polyacrylate, polysiloxane, polymethacrylate, polysaccharide, polysaccharide, polyvinyl alcohol, and the like. The moieties are connected by ester or ether linkages.

상기 광반응부는 탄소-탄소 삼중 결합을 포함하고, 하나 혹은 두 개의 벤젠 고리를 가지며, 이 벤젠 고리에 H, F, Cl, CN, CF3, OCF3, CnH2n+1, OCnH2n+1의 치환기를 함유한다.The photoreaction portion contains a carbon-carbon triple bond, and has one or two benzene rings, in which the H, F, Cl, CN, CF 3 , OCF 3 , C n H 2n + 1 , OC n H It contains a substituent of 2n + 1 .

본 발명에 사용된 광배향막의 실시 예로서, 아래와 같은 구조식을 들 수 있다.As an example of the photo-alignment film used for this invention, the following structural formula is mentioned.

[구조식][constitutional formula]

여기서 상기 P1은 폴리사카라이드 또는 폴리비닐알콜이며, P2는 폴리아크릴레이트 또는 폴리메타크릴레이트이고, P3은 폴리실록산이다. 이때 X, Y, Z는 H, F, Cl, CN, CF3, OCF3, CnH2n+1(n=1∼7), OCnH2n+1(n=1∼7)이고, k=0∼1이며, m=0∼7이다.Wherein P 1 is polysaccharide or polyvinyl alcohol, P 2 is polyacrylate or polymethacrylate, and P 3 is polysiloxane. Wherein X, Y, Z are H, F, Cl, CN, CF 3 , OCF 3 , C n H 2n + 1 (n = 1-7), OC n H 2n + 1 (n = 1-7), k = 0-1 and m = 0-7.

이 같은 광배향물질을 MEK, THF, Toluene 등의 유기용제에 녹여 용액을 제조한 다음, 이 용액을 PET, PC, TAC와 같은 플라스틱 필름(plastric film) 위에 롤 코팅(roll coating) 방법에 의해 박막도포 한 후 도포된 필름을 건조기를 통과시켜 용제를 제거한 다음, UV 조사기를 이용하거나 광조사 없이 건조과정만을 거친 후 되감는다.The photo-alignment material is dissolved in an organic solvent such as MEK, THF, Toluene, etc. to prepare a solution, and then the solution is thin-film roll-coated on a plastic film such as PET, PC, or TAC. After application, the applied film is passed through a dryer to remove the solvent, and then rewinded after only drying with UV irradiation or without light irradiation.

이와 같이 광배향막이 도포된 필름 위에 경화성 네마틱 액정을 MEK, THF, 톨루엔(Toluene) 등의 유기용제에 녹인 용액을 롤 코팅 방법에 의해 박막도포 하였으며, 도포된 필름이 건조기를 통과하면 용제가 제거됨과 동시에 네마틱 액정이 수직배향하게 된다.Thus, a thin film of a solution in which a curable nematic liquid crystal was dissolved in an organic solvent such as MEK, THF, and toluene was applied by a roll coating method on a film coated with an optical alignment layer, and the solvent was removed when the applied film passed through the dryer. At the same time, the nematic liquid crystal is vertically aligned.

상기 건조기에서 나온 필름을 UV 조사기를 이용 광조사하여 경화반응을 진행시켜 수직배향된 상태를 고정시켜 수직배향된 액정필름을 제조하였다.The film from the dryer was irradiated with light using a UV irradiator to perform a curing reaction to fix a vertically aligned state, thereby preparing a vertically aligned liquid crystal film.

제조된 액정필름의 수직배향 여부는 수직으로 정렬된 편광판(crossed polarizer) 사이에 필름을 놓고 소광률(extinction rate)을 측정하고, 굴절률을 측정함으로써 확인할 수 있으며, 액정필름의 두께는 코팅 용액 제조시의 농도, 코팅 속도 등을 조절함에 의해 1 - 20㎛까지 조절할 수 있다.Vertical alignment of the prepared liquid crystal film can be confirmed by placing the film between vertically aligned polarizers and measuring extinction rate and measuring the refractive index. By adjusting the concentration, coating speed and the like can be adjusted to 1-20㎛.

위와 같이 제작된 수직배향 액정필름 보상판을 콜레스테릭 액정 필름과 λ/4 위상차 필름 사이에 삽입, 합착시키고 λ/4 위상차 필름 위에 선편광판을 합착시켜 반사형 편광판을 제작하였다.The vertical alignment liquid crystal film compensation plate prepared as described above was inserted and bonded between the cholesteric liquid crystal film and the lambda / 4 phase difference film, and the linear polarizing plate was bonded to the lambda / 4 phase difference film to prepare a reflective polarizing plate.

이때 사용한 콜레스테릭 액정 필름은 입사하는 빛의 일부(50％)를 좌원 또는 우원으로 편광시켜서 통과시키고, 나머지 일부(50％)를 투과된 빛과 반대되는 편광의 빛으로 반사시키는 역할을 하는 것으로 전 가시광선 영역(400㎚ - 800㎚)을 덮을 수 있게 여러 층의 서로 다른 파장 영역을 가진 액정층을 적층하여 제작하였으며, 장파장쪽이 광원쪽으로 향하게 하고 단파장쪽이 보상필름과 접하게 했다.The cholesteric liquid crystal film used at this time serves to pass a part of the incident light (50%) by polarizing it to the left or right circle and reflect the remaining part (50%) to the light of polarization opposite to the transmitted light. Liquid crystal layers having different wavelength regions of different layers were laminated to cover the entire visible light region (400 nm-800 nm), with the long wavelength side facing the light source and the short wavelength side facing the compensation film.

보상 필름은 전술한 방법으로 제작하였으며, 콜레스테릭 액정층이 각도에 따라 투과하는 색깔 및 편광도가 바뀌기 때문에 이런 현상의 적절한 보상을 위해 4-6㎛의 두께를 가진 필름을 사용하였다.Compensation film was produced by the above-described method, because the color and polarization of the cholesteric liquid crystal layer is transmitted according to the angle is changed to use a film having a thickness of 4-6㎛ for proper compensation of this phenomenon.

상기 λ/4 위상차 필름은 원편광의 빛을 선편광의 빛으로 만들어주기 위하여사용되며, 중심 파장이 460㎚인 위상차 필름을 사용하였다.The λ / 4 retardation film is used to make circularly polarized light into linearly polarized light, and a retardation film having a center wavelength of 460 nm is used.

그리고 선편광판은 λ/4 위상차 필름을 통과한 빛의 선편광도가 모든 파장에 대해 균일하게 높지 않기 때문에 높은 선 편광도를 얻기 위해서 사용하였다.And since the linear polarization degree of the light which passed the (lambda) / 4 phase (s) difference film was not uniformly high for all wavelengths, the linear polarizing plate was used in order to acquire a high linear polarization degree.

도 1a 및 도 1b 는 본 발명이 적용되는 보상판이 삽입된 경우(실선)와 삽입 되지 않은 경우(점선)의 각도에 따른 휘도 변화 곡선 및 색좌표의 변화 곡선 구조도.1A and 1B are diagrams illustrating a structure of change in luminance and curves of color coordinates according to angles when a compensation plate to which the present invention is applied is inserted (solid line) and not inserted (dotted line).

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

도 1a 및 도 1b 는 본 발명이 적용되는 보상판이 삽입된 경우(실선)와 삽입되지 않은 경우(점선)의 각도에 따른 휘도 변화 곡선 및 색좌표의 변화 곡선 구조도이다. 우선 광배향물질을 합성하였다.1A and 1B are structural diagrams of luminance change curves and color coordinates according to angles when a compensation plate to which the present invention is applied is inserted (solid line) and not inserted (dotted line). First, a photo-alignment material was synthesized.

먼저 그 구조는 상기 구조식에 나타나 있으며, P1으로서 폴리사카라이드를 사용하고, 탄소-탄소 이중결합을 광반응부로 가지며, m과 k는 O, X는 OC5H11, Y는 H의 구조를 갖는 관능기를 사용하였다.First, the structure is shown in the above structural formula, using polysaccharide as P 1 , having a carbon-carbon double bond as a photoreaction portion, m and k is O, X is OC 5 H 11 , Y is H Having functional group was used.

이 배향물질을 MEK에 2wt％의 농도를 갖도록 용액을 제조하였으며, 이 용액을 롤 코팅(roll coating) 방법에 의해 PET 필름 위에 도포하고 건조기에서 용제를 건조시킨 후 UV 광조사를 하였다.This alignment material was prepared to have a concentration of 2wt% in MEK, and this solution was applied on a PET film by a roll coating method, and the solvent was dried in a dryer, followed by UV light irradiation.

이때, 건조 조건은 75℃이었으며, UV 광조사는 300W(중심파장 360㎚) 램프(lamp)를 사용하였다.At this time, the drying conditions were 75 ℃, UV light irradiation used a 300W (center wavelength 360nm) lamp (lamp).

이렇게 광배향막이 도포된 필름 위에 네마틱 액정물질을 도포하였는데, 이때 네마틱 액정물질로는 경화성 네마틱 액정물질(BASF사)을 사용하였다.The nematic liquid crystal material was applied onto the film on which the photo-alignment film was applied. At this time, a curable nematic liquid crystal material (BASF) was used as the nematic liquid crystal material.

먼저 MEK에 경화성 네마틱 액정물질과 광개시제(IG 184, Ciba-Geigy)를 녹여 용액농도 40wt％, 광개시함량 5wt％로 용액을 제조하였다.First, a curable nematic liquid crystal material and a photoinitiator (IG 184, Ciba-Geigy) were dissolved in MEK to prepare a solution with a solution concentration of 40 wt% and a photo initiator content of 5 wt%.

이렇게 제조된 용액을 롤 코팅 방법에 의해 광배향막이 도포된 상기 PET 필름 위에 박막을 도포한 후 건조기에서 용제를 건조 제거하여 네마틱 액정물질을 수직배향시킨 다음 UV 광조사에 의해 중합을 진행시켜 수직배향 상태를 고정시키며 필름을 제조하였다.After applying the thin film on the PET film to which the photo-alignment film is applied by the roll coating method, the solution thus prepared is vertically oriented by nematic liquid crystal material by drying and removing the solvent in a drier, and then proceeding polymerization by UV light irradiation. The film was prepared while fixing the orientation state.

이때, 건조 조건은 80℃이었으며, UV 광조사는 300W(중심파장 360㎚) 램프를 사용하였다.At this time, the drying conditions were 80 ℃, UV light irradiation used a 300W (center wavelength 360nm) lamp.

제조된 수직배향(homeotropic) 네마틱 액정필름의 두께는 4㎛이고, 굴절률 측정을 통해 Nx= Ny= 1.535, Nz= 1.668의 결과를 얻었으며, 이로부터 수직배향된 액정필름이 제조되었음을 확인하였다.The produced homeotropic nematic liquid crystal film had a thickness of 4 μm, and the refractive index measurement resulted in N x = N y = 1.535 and N z = 1.668, from which a vertically aligned liquid crystal film was prepared. Confirmed.

상기 구조식에 나타낸 바와 같이 P3로서 폴리실록산을 사용하고, 탄소-탄소 삼중결합을 광반응부로 가지며, m은 1, k는 0, X는 OC5H11, Y는 H의 구조를 갖는 관능기를 사용하였다.As shown in the above structural formula, polysiloxane is used as P 3 , carbon-carbon triple bond is used as the photoreaction portion, m is 1, k is 0, X is OC 5 H 11 , and Y is a functional group having a structure of H. It was.

상기 배향물질은 MEK에 2wt％의 농도를 갖도록 용액을 제조하였으며, 이 용액을 롤 코팅 방법에 의해 PET 필름 위에 도포한 후 건조기에서 용제를 제거하였다.The alignment material was prepared to have a concentration of 2wt% in MEK, and the solution was applied onto the PET film by a roll coating method, and then the solvent was removed from the dryer.

이때, 건조 조건은 80℃이었으며, UV 광조사는 300W(중심파장 360㎚) 램프를 사용하였다.At this time, the drying conditions were 80 ℃, UV light irradiation used a 300W (center wavelength 360nm) lamp.

상기 제조된 수직배향(homeotropic) 네마틱 액정필름의 두께는 3.7㎛이었으며, 굴절률 측정을 통해 Nx = Ny = 1.538, Nz = 1.652의 결과를 얻었으며, 이로부터 수직배향된 액정필름이 제조되었음을 확인하였다.The thickness of the prepared homeotropic nematic liquid crystal film was 3.7 μm, and the results of Nx = Ny = 1.538 and Nz = 1.652 were obtained by measuring the refractive index, and it was confirmed that the vertically aligned liquid crystal film was prepared. .

상기 구조에 따른 광배향물질 합성의 작동 및 그에 따른 설명을 보면 다음과 같다.Referring to the operation and description thereof according to the structure of the optical alignment material according to the above structure.

상기와 같이 서로 다른 선택반사 파장영역을 갖는 우선성 나선구조의 콜레스테릭 액정 필름을 적층하여 선택반사 파장영역이 전 가시광선 영역을 포함하는 원편광 분리층을 제조하였다.As described above, a cholesteric liquid crystal film having a preferential spiral structure having different selective reflection wavelength regions was stacked to prepare a circularly polarized light separation layer in which the selective reflection wavelength region includes all visible light regions.

그 위에 상기한 것과 같이 제작한 4.7㎛ 두께의 수직배향된 액정필름을 콜레스테릭 액정층의 단파장쪽에 합착하였다.The 4.7 micrometer-thick vertically oriented liquid crystal film produced as mentioned above was bonded to the short wavelength side of a cholesteric liquid crystal layer.

그리고 중심파장이 460㎚인 폴리카보네이트 재질의 λ/4 위상차 필름을 수직배향된 액정 필름 위에 합착하고, 그 위쪽에 선편광판을 다시 합착하여 반사형 편광판을 제작하였다.Then, the λ / 4 retardation film made of polycarbonate having a center wavelength of 460 nm was bonded onto the vertically aligned liquid crystal film, and the linear polarizing plate was again bonded to the upper side to prepare a reflective polarizing plate.

제작된 반사형 편광판을 LCD 후광조명(backlight) 위에 설치하여 수직배향된 액정필름 보상판이 삽입된 경우와 삽입되지 않은 경우에 대해서 시야각에 따른 휘도 변화 및 색좌표를 조사하였다.The fabricated reflective polarizer was installed on the LCD backlight, and the luminance variation and color coordinates according to the viewing angle were examined for the vertically aligned liquid crystal film compensation plate and the non-inserted liquid crystal film compensation plate.

상기 도 1a에서 볼 수 있듯이 보상판이 삽입된 경우의 각도에 따른 휘도 변화가 보상판이 삽입되지 않은 경우의 각도에 따른 휘도 변화보다 작음을 알 수 있다.As shown in FIG. 1A, it can be seen that the change in luminance according to the angle when the compensation plate is inserted is smaller than the change in luminance according to the angle when the compensation plate is not inserted.

또한 상기 도 1b에서 보듯이 색좌표의 변화 역시 보상판이 삽입되지 않은 경우보다 각도에 따른 변화가 작은 것을 볼 수 있으며, 특히 색좌표의 변화에서는 50°와 60°에서 심한 차이가 있음을 알 수 있다.In addition, as shown in FIG. 1B, the change in color coordinates is also smaller depending on the angle than when the compensation plate is not inserted. In particular, the change in color coordinates shows a significant difference at 50 ° and 60 °.

상술한 바와 같이 본 발명은, 배향막을 사용하여 수직배향시킨 액정 필름을 이용한 반사형 콜레스테릭 액정 편광판의 시야각에 따른 색차 및 휘도를 개선시킴으로써, 액정 표시장치(LCD)의 시야각 특성을 개선시키는 보상 필름이나 광소자로서 사용할 수 있는 효과를 가진다.As described above, the present invention compensates for improving the viewing angle characteristic of a liquid crystal display (LCD) by improving the color difference and luminance according to the viewing angle of the reflective cholesteric liquid crystal polarizing plate using the liquid crystal film vertically aligned using the alignment film. It has the effect which can be used as a film or an optical element.

Claims (7)

탄소-탄소 삼중결합 및 탄소-탄소 이중결합의 광반응 관능기를 가진 배향막을 사용하여 경화성 네마틱 액정을 수직배향시킨 후 광조사를 통해 배향상태를 고정시켜7 수직 배향 필름을 제조하는 제 1 과정과;A first process of preparing a vertical alignment film by vertically aligning the curable nematic liquid crystal using an alignment film having a carbon-carbon triple bond and a carbon-carbon double bond photoreactive functional group, and then fixing the alignment state through light irradiation; ; 제조된 수직배향 필름을 이용하여 반사형 콜레스테릭 액정 편광판의 시야각 에 따른 색차 및 휘도를 개선하는 제 2 과정을 포함하는 것을 특징으로 하는 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법.Comprising a second process for improving the color difference and the luminance according to the viewing angle of the reflective cholesteric liquid crystal polarizing plate using the prepared vertical alignment film, color difference and luminance compensation method according to the viewing angle of the reflective polarizing plate. 제 1 항에 있어서, 상기 제 1 과정은The method of claim 1, wherein the first process is 광배향물질을 MEK, THF, 톨루엔(Toluene)의 유기용제에 녹여 용액을 제조하는 제 1 단계와;A first step of preparing a solution by dissolving the photo-alignment material in an organic solvent of MEK, THF, and toluene; 상기 제조된 용액을 PET, PC, TAC의 플라스틱 위에 롤 코팅 방법을 사용하여 박막도포하는 제 2 단계와;A second step of coating the prepared solution on a plastic film of PET, PC, TAC using a roll coating method; 도포된 필름을 건조기를 통과시켜 용제를 제거한 후 UV 조사기를 이용하여 조사시키거나 광조사없이 건조과정만을 거친 후 되감는 제 3 단계와;A third step of removing the solvent by passing the applied film through a dryer and irradiating with a UV irradiator or rewinding only after drying without light irradiation; 상기 건조기에서 나온 필름위에 점화성 네마틱 액정을 도포하고 건조하여 UV 조사기를 이용해 광조사한 후 경화반응을 진행시켜 수직배향된 상태를 고정시켜 수직배향된 액정필름을 제조하는 제 4 단계로 이루어진 것을 특징으로 하는 반사형편광판의 시야각에 따른 색차 및 휘도 보상 방법.The fourth step of manufacturing a vertically oriented liquid crystal film by applying a ignitable nematic liquid crystal on the film from the dryer and drying and irradiating light using a UV irradiator and then proceeding the curing reaction to fix the vertically oriented state Color difference and luminance compensation method according to the viewing angle of the reflective polarizer. 제 2 항에 있어서, 상기 제 4 단계는The method of claim 2, wherein the fourth step 양복굴절(positive birefringence) 특성을 갖는 보상필름인 수직배향액정필름을 제조하여 사용하는 것을 특징으로 하는 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법.Color difference and luminance compensation method according to the viewing angle of the reflective polarizing plate, characterized in that for producing and using a vertical alignment liquid crystal film that is a compensation film having a positive birefringence characteristics. 제 3 항에 있어서, 상기 수직배향액정필름은According to claim 3, wherein the vertical alignment liquid crystal film 폴리사카리이드, 폴리비닐알콜, 폴리아크릴레이트, 폴리메타크릴레이트 및 폴리실록산의 감광성 고분자 배향막의 고분자 주사슬을 갖는 것을 특징으로 하는 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법.A method of compensating color difference and luminance according to a viewing angle of a reflective polarizing plate, comprising a polymer main chain of a photosensitive polymer alignment layer of polysaccharide, polyvinyl alcohol, polyacrylate, polymethacrylate, and polysiloxane. 제 3 항에 있어서, 상기 수직배향액정필름은According to claim 3, wherein the vertical alignment liquid crystal film 감광성 고분자 배향막의 광반응부와 고분자 주쇄가 에테르(ether) 또는 에스테르(ester) 결합으로 이루어진 것을 특징으로 하는 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법.Color difference and luminance compensation method according to the viewing angle of the reflective polarizing plate, characterized in that the photoreaction portion of the photosensitive polymer alignment layer and the polymer backbone is composed of ether (ether) or ester (ester) bond. 제 3 항에 있어서, 상기 수직배향액정필름은According to claim 3, wherein the vertical alignment liquid crystal film 기판(substrate)로서 플라스틱 판(plastic sheet)이나 필름(film)을 사용하여 제조하는 것을 특징으로 하는 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법.Color difference and luminance compensation method according to the viewing angle of the reflective polarizing plate, characterized in that the manufacturing using a plastic sheet (film) or a film as a substrate (substrate). 제 1 항에 있어서, 상기 제 2 과정은The method of claim 1, wherein the second process 콜레스테릭 액정필름에 입사하는 빛의 일부를 좌원 또는 우원으로 편광시켜 통과시키고 나머지 일부를 투과된 빛과 반대되는 편광의 빛으로 반사시켜 전 가시광선 영역을 덮어 여러 층의 서로 다른 파장 영역을 가진 액정층을 적층하여 제작하는 제 1 단계;Part of the light incident on the cholesteric liquid crystal film is polarized to the left circle or the right circle, and the other part is reflected to the polarized light opposite to the transmitted light. A first step of stacking and manufacturing a liquid crystal layer; 상기 필름의 장파장쪽을 광원쪽으로 향하게 하고 단파장쪽을 보상필름과 접하게 하는 제 2 단계;A second step of directing the long wavelength side of the film toward the light source and contacting the short wavelength side with the compensation film; 제작된 수직배향 액정필름을 콜레스테릭 액정필름과 소정 위상차 필름 사이에 삽입 및 합착시키는 제 3 단계;Inserting and bonding the produced vertically aligned liquid crystal film between the cholesteric liquid crystal film and the predetermined retardation film; 상기 소정 위상차 필름 위에 선편광판을 합착시켜 반사형 편광판을 제작하는 제 4 단계; 및A fourth step of manufacturing a reflective polarizing plate by bonding a linear polarizing plate on the predetermined retardation film; And 상기 보상필름을 콜레스테릭 액정층이 각도에 따라 투과하는 색깔 및 편광도의 변화에 대한 보상을 위해 일정 두께를 가진 필름을 사용하여 보상을 하는 제 5단계로 이루어진 것을 특징으로 하는 반사형 편광판의 시야각에 따른 색차 및 휘도 보상 방법.Viewing angle of the reflective polarizer according to the fifth step of compensating the compensation film using a film having a predetermined thickness to compensate for the change in color and polarization degree transmitted by the cholesteric liquid crystal layer according to the angle Color difference and luminance compensation method according to.
KR1019990058305A 1999-12-16 1999-12-16 Compensation Method of color and luminance along viewing angle for reflective polarizer KR20010056719A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1019990058305A KR20010056719A (en) 1999-12-16 1999-12-16 Compensation Method of color and luminance along viewing angle for reflective polarizer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1019990058305A KR20010056719A (en) 1999-12-16 1999-12-16 Compensation Method of color and luminance along viewing angle for reflective polarizer

Publications (1)

Publication Number Publication Date
KR20010056719A true KR20010056719A (en) 2001-07-04

Family

ID=19626361

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1019990058305A KR20010056719A (en) 1999-12-16 1999-12-16 Compensation Method of color and luminance along viewing angle for reflective polarizer

Country Status (1)

Country Link
KR (1) KR20010056719A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100474057B1 (en) * 2000-04-24 2005-03-08 가부시끼가이샤 도시바 A liquid crystal display device
KR100738314B1 (en) * 2005-08-02 2007-07-12 주식회사 에이스 디지텍 Method for Manufacturing compenasation film for angular field of view and compenasation film for angular field of view using thereof
KR101073328B1 (en) * 2003-12-16 2011-10-12 엘지디스플레이 주식회사 Device and fabrication method for compensation film of lcd

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07281028A (en) * 1994-04-08 1995-10-27 Fuji Photo Film Co Ltd Optical anisotropic sheet and liquid crystal display element using it
KR960016692A (en) * 1985-11-29 1996-05-22 미쓰다 가쓰시게 Semiconductor device
KR960038457A (en) * 1995-04-11 1996-11-21 오오니시 미노루 Optical compensation sheet
JPH10278123A (en) * 1997-02-07 1998-10-20 Fuji Photo Film Co Ltd Optical compensating sheet, manufacture thereof, and liquid crystal displaying device using the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR960016692A (en) * 1985-11-29 1996-05-22 미쓰다 가쓰시게 Semiconductor device
JPH07281028A (en) * 1994-04-08 1995-10-27 Fuji Photo Film Co Ltd Optical anisotropic sheet and liquid crystal display element using it
KR960038457A (en) * 1995-04-11 1996-11-21 오오니시 미노루 Optical compensation sheet
JPH10278123A (en) * 1997-02-07 1998-10-20 Fuji Photo Film Co Ltd Optical compensating sheet, manufacture thereof, and liquid crystal displaying device using the same

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100474057B1 (en) * 2000-04-24 2005-03-08 가부시끼가이샤 도시바 A liquid crystal display device
KR101073328B1 (en) * 2003-12-16 2011-10-12 엘지디스플레이 주식회사 Device and fabrication method for compensation film of lcd
KR100738314B1 (en) * 2005-08-02 2007-07-12 주식회사 에이스 디지텍 Method for Manufacturing compenasation film for angular field of view and compenasation film for angular field of view using thereof

Similar Documents

Publication Publication Date Title
US6822713B1 (en) Optical compensation film for liquid crystal display
KR101499363B1 (en) Liquid Crystal Device
JP4515984B2 (en) Optical elements
US20130201435A1 (en) Liquid crystal cell
KR100684182B1 (en) A method of making an element of a liquid crystal polymer, an element of a liquid crystal polymer made by the method and an optical device comprising the element
KR100767587B1 (en) A coated compensate film for lcd and the fabrication method
KR20010056719A (en) Compensation Method of color and luminance along viewing angle for reflective polarizer
KR980010972A (en) Reflective Liquid Crystal Display
KR101655283B1 (en) Optical film without additional aligned film and method of making the same
US20190346607A1 (en) Retardation substrate, liquid crystal element and liquid crystal module
Stockley et al. Active liquid crystal devices incorporating liquid crystal polymer thin film waveplates
KR20010065714A (en) Process for the homeotropic aligned liquid crystal film using alignment layer
JPH10161132A (en) Liquid crystal oriented film and its production
CN110678788B (en) Liquid crystal display device, method for manufacturing liquid crystal display device, and retardation layer forming monomer
EP2933273A1 (en) Polymerizable composition
Meng High-Performance Alignment Thin Films for Advanced Displays
KR20030039805A (en) STN LCD Unit Using Colesteric Liquid Crystal and Method Thereof
KR19990084546A (en) Liquid Crystal Display Device and Liquid Crystal Alignment Method
KR20100125620A (en) Reflective polarizing film comprising cholesteric liquid crystal and photo-curable monomer and method of preparing the same

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E601 Decision to refuse application