Liquid-crystal composition and liquid-crystal display device employing the same

A liquid-crystal composition comprises a first component and a second component, wherein the first component comprises one or more compounds represented by Formula (I) and the second component comprises one or more compounds represented by Formula (II):

• wherein R1 and R2 are independently F, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C2-C10 alkenyl group, a C2-C10 alkenyloxy, or a C2-C10 alkynyl group, where the C1-C10 alkyl group, the C1-C10 alkoxy group, the C2-C10 alkenyl group, the C2-C10 alkenyloxy, or the C2-C10 alkynyl group is unsubstituted or at least one —CH2— thereof is substituted by —O—, —NH—, —S—, —CO—, —O—CO—, —CO—O— or —O—CO—O—, provided that the —O—, —NH—, —S—, —CO—, —O—CO—, —CO—O— or —O—CO—O— do not directly bond to one another, and/or at least one hydrogen of the C1-C10 alkyl group, the C1-C10 alkoxy group, the C2-C10 alkenyl group, the C2-C10 alkenyloxy, or the C2-C10 alkynyl group is unsubstituted or substituted by halogen, CN, or CF3;
• each of A1, A2, A3, and A4 independently represents (i) an unsubstituted
• (ii) a substituted
• where at least one —CH2— thereof is substituted by —O—, —NH—, —S—, —CO—, —O—CO—, —CO—O— or —O—CO—O— and the —O—, —NH—, —S—, —CO—, —O—CO—, —CO—O— or —O—CO—O— do not directly bond to one another, (iii) a substituted
• where at least one hydrogen thereof is substituted by halogen, CN, or CF3, (iv) an unsubstituted
• (v) a substituted
• where at least one hydrogen thereof is substituted by halogen, CH3, CN, or CF3, (vi) a substituted
• where at least one —CH— thereof is substituted by —N—, (vii) an unsubstituted
• and/or (viii) a substituted
• where at least one —CH2— thereof is substituted by —O—, —NH—, —S—, —CO—, —O—CO—, —CO—O— or —O—CO—O— and the —O—, —NH—, —S—, —CO—, —O—CO—, —CO—O— or —O—CO—O— do not directly bond to one another;
• A1, A2, A3, and A4 are the same or different;
• each of Z1, Z2, and Z3 independently represents a single bond, —CF2—O—, —O—CF2—, —CO—O—, or —O—CO—, and at least one of Z1, Z2, and Z3 is —CF2—O— or —O—CF2—;
• and
• each of the m, m′, n and n′ independently represents an integer from 0 to 6, wherein the m, m′, n and n′ are the same or different.