Guest-host liquid crystal display devices with silane surfactant

• US 4,357,374 A
• Filed: 12/02/1980
• Issued: 11/02/1982
• Est. Priority Date: 12/13/1979
• Status: Expired due to Term

• Current Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Original Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Inventors: Ogawa, Shoichi
• Primary Examiner(s): MCCAMISH, MARION E
• Application Number:
  US06/212,122
• Time in Patent Office: 700 Days
• Field of Search: 428/1, 428/333, 428/336, 428/339, 428/447
• US Class Current: 428/1.32
• CPC Class Codes: C09K 2323/023 Organic silicon compound, e.g. organosilicon
• CPC Class Codes: C09K 2323/033 Silicon compound, e.g. glass or organosilicon
• CPC Class Codes: G02F 1/1337 Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
• CPC Class Codes: G02F 1/133719 with coupling agent molecules, e.g. silane
• CPC Class Codes: G02F 1/13725 based on guest-host interaction G02F1/13762, G02F1/13737, take precedence
• CPC Class Codes: Y10T 428/261 In terms of molecular thickness or light wave length
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/269 including synthetic resin or polymer layer or component
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

A guest-host liquid crystal display device has tilted homeotropic orientation using a nematic liquid crystal having negative dielectric anisotropy as a host and a dichroic dye as a guest which is prepared by overcoating an inorganic insulating layer; treating said layer to provide orientation; and treating the layer with a silane surfactant.

Claims

1. A guest-host liquid crystal display device having tilted homeotropic orientation using a nematic liquid crystal having negative dielectric anisotropy as a host and a dichroic dye as guest which is prepared by placing the nematic liquid crystal between two glass plates, each of the glass plates, on the surface facing the nematic liquid crystal, having an electrode thereon;

said electrode having been coated with an inorganic insulating layer;

said inorganic insulating layer having been treated to provide orientation by being rubbed or polished in a single direction; and

coating the so-treated layer with a silane surfactant which imparts homeotropic orientation.

2. The guest-host liquid crystal display device according to claim 1 wherein said inorganic insulating layer is a made of TiO₂, ZrO₂, HfO₂, GeO₂, SiO₂, Al₂ O₃, CeO₂, CaF₂ or MgF₂ in a thickness of more than 300 A.

3. The guest-host liquid crystal display device according to claim 2 wherein said orientation is given by a rubbing or polishing treatment in a non-vacuum process.

4. The guest-host liquid crystal display device according to claim 3 wherein said silane surfactant is an organic silane compound having the formula

5. The guest-host liquid crystal display device according to claim 4 wherein said silane surfactant is an organic silane compound having the formula

6. The guest-host liquid crystal display device according to claim 2 wherein said inorganic insulating layer is made of ZrO₂ or Al₂ O₃.

7. The guest-host liquid crystal display device according to claim 6 wherein said inorganic insulating layer is made of ZrO₂.