Nematic liquid crystal composition

• US 20050012074A1
• Filed: 06/30/2004
• Published: 01/20/2005
• Est. Priority Date: 07/09/2003
• Status: Active Grant

• Current Assignee: TCL China Star Optoelectronics Technology Co. Ltd. (TCL Technology Group Corp.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Ban, Byeong-Seob
• Granted Patent: US 7,063,805 B2
• Time in Patent Office: Days
• US Class Current: 252/299.630
• CPC Class Codes: C09K 19/0403 the structure containing one or more specific, optionally substituted ring or ring systems
• CPC Class Codes: C09K 19/3003 Compounds containing at least two rings in which the different rings are directly linked (covalent bond)
• CPC Class Codes: C09K 19/44 containing compounds with benzene rings directly linked
• CPC Class Codes: C09K 19/46 containing esters
• CPC Class Codes: C09K 2019/0407 containing a carbocyclic ring, e.g. dicyano-benzene, chlorofluoro-benzene or cyclohexanone
• CPC Class Codes: C09K 2019/0444 characterized by a linking chain between rings or ring systems, a bridging chain between extensive mesogenic moieties or an end chain group

Abstract

A nematic liquid crystal composition includes a compound of formula (1) and a host mixture:
wherein ‘R’ is chosen from C_nH_2n+1O, C_nH_2n+1, C_nH_2n+1S or C_nH_2n−1; ‘n’ is an integer of 1 to 15; ‘A’ is
‘a’ is 0 or 1; ‘B’ is —CH₂CH₂—, —C═C—, —C≡C— or
‘b’ is 0 or 1; ‘D’ is
—CH₂CH₂—, —C═C— or —C≡C—; ‘d’ is 0 or 1; ‘X’ is H, F, Cl, Br, NCS or CN; and ‘Y’ is from NCS, SCN or F. A liquid crystal display apparatus employing the nematic liquid crystal composition has a high response speed and a high phase transition temperature. In addition, the nematic liquid crystal composition has an augmented birefringence and a dielectric anisotropy. The liquid crystal display apparatus using the nematic liquid crystal composition may have an enhanced brightness.

Claims

1. A nematic liquid crystal composition comprising a compound of formula (1) and a host mixture:

2. The nematic liquid crystal composition of claim 1, wherein the nematic liquid crystal composition comprises about 1% to about 90% by weight of the compound of formula (1) and about 10% to about 99% by weight of the host mixture.

3. The nematic liquid crystal composition of claim 1, wherein the host mixture comprises compounds of formulae (2) to (15):

4. The nematic liquid crystal composition of claim 1, wherein the host mixture comprises compounds of formulae (2) to (8) and (12) to (18):

5. The nematic liquid crystal composition of claim 1, wherein the nematic liquid crystal composition is used in a twisted nematic liquid crystal display apparatus.

6. The nematic liquid crystal composition of claim 1, wherein the nematic liquid crystal composition is used in a super twisted nematic liquid crystal display apparatus.

7. The nematic liquid crystal composition of claim 1, wherein the nematic liquid crystal composition is used in a thin film transistor twisted nematic liquid crystal display apparatus.

8. The nematic liquid crystal composition of claim 1, wherein the nematic liquid crystal composition is used in an in-plane switching liquid crystal display apparatus.

9. The nematic liquid crystal composition of claim 1, wherein the nematic liquid crystal composition is used in a vertical alignment mode liquid crystal display apparatus.