US 12,480,049 B2
Compound and liquid crystal composition
Valerii Vladimirovich Vashchenko, Hong Kong (CN); Olena V. Vashchenko, Hong Kong (CN); Abhishek Kumar Srivastava, Hong Kong (CN); Zhibo Sun, Hong Kong (CN); Zhengnan Yuan, Hong Kong (CN); and Hoi Sing Kwok, Hong Kong (CN)
Assigned to The Hong Kong University of Science and Technology, Hong Kong (CN)
Filed by The Hong Kong University of Science and Technology, Hong Kong (CN)
Filed on Feb. 7, 2023, as Appl. No. 18/165,361.
Claims priority of provisional application 63/307,611, filed on Feb. 7, 2022.
Prior Publication US 2023/0250338 A1, Aug. 10, 2023
Int. Cl. C09K 19/02 (2006.01); C09K 19/12 (2006.01); C09K 19/32 (2006.01); C09K 19/34 (2006.01)
CPC C09K 19/0225 (2013.01) [C09K 19/12 (2013.01); C09K 19/322 (2013.01); C09K 19/3444 (2013.01); C09K 19/345 (2013.01); C09K 2019/122 (2013.01); C09K 2019/123 (2013.01); C09K 2019/323 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A ferroelectric liquid crystal (FLC) material for deformed helix FLC (DHFLC) electro-optical mode devices comprising at least two components and shows optimum electro-optical properties, wherein at least one FLC component is a chiral compound of Formula (I):

OG Complex Work Unit Chemistry
wherein:
n is 0 or 1;
R1 and R4 each independently 1,4-phenylene substituted with one or more substituents selected from the group consisting of halogen and methyl, pyrimidine-2,5-diyl or pyridine-2,5-diyl, wherein the pyrimidine-2,5-diyl and the pyridine-2,5-diyl are optionally substituted with one or more substituents selected from the group consisting of halogen and methyl;
R2, and R3 each independently are 1,4-phenylene, or pyrimidine-2,5-diyl, or pyridine-2,5-diyl, optionally substituted with one or more substituents selected from the group consisting of halogen and methyl;
A1 and A2 are independently absent, that has meaning the group W1 or W2 are directly attached to the rings R1 or R4, or selected from the group consisting of —O—, —S—, and ester; and
W1 and W2 are independently chiral alkyl CmH2m+1 or alkenyl CmH2m, wherein m=4-14, and optionally wherein one or more hydrogens are independently replaced by F, Cl or cyano, and optionally one or more CH2 are independently replaced with CF2, O, or —CO— groups provided that two O atoms are not linked together, and
wherein at least one FLC component is at least one achiral smectic C liquid crystal compound of Formula (II):

OG Complex Work Unit Chemistry
wherein:
R5, R6, R7, and R8 independently are 1,4-phenylene, or pyrimidine-2,5-diyl, or pyridine-2,5-diyl, optionally substituted with at least one substituent selected from the group consisting of halogen and methyl;
k is 0 or 1;
A3 and A4 are independently absent or selected from the group consisting of —O—, —S—, and ester; and
W3 and W4 are independently alkyl CmH2m+1 or alkenyl CmH2m, wherein m=4-12, and optionally one or more hydrogens are independently replaced by F, furthermore, optionally one or more CH2 are independently replaced with CF2, O, or —CO— groups provided that two O atoms are not linked together, wherein the FLC material exhibits a tilt angle between 35-47 degrees and a spontaneous polarization larger than 100 nC/cm2 at 25° C. and 1 atm.