Liquid crystal composition, liquid crystal display device, and liquid crystal display

1. A liquid crystal composition comprising at least one compound represented by General Formula (i-c-2) and at least one compound represented by General Formula (ii)

where

R ii1 represents an alkyl group having 1 to 8 carbon atoms; and one —CH 2 — or at least two —CH 2 — not adjoining each other in the alkyl group are each independently optionally substituted with —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—;

R ii2 represents a fluorine atom, a chlorine atom, a cyano group, or an alkyl group having 1 to 8 carbon atoms; one —CH 2 — or at least two —CH 2 — not adjoining each other in the alkyl group are each independently optionally substituted with —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—; and one or two or more hydrogen atoms of the alkyl group are each independently optionally substituted with a fluorine atom;

A ii1 and A ii2 each independently represent a 1,4-cyclohexylene group of which one —CH 2 — or at least two —CH 2 — not adjoining each other are optionally substituted with —O— or a 1,4-phenylene group of which at least one hydrogen atom is optionally substituted with a fluorine atom;

Z ii1 and Z ii2 each independently represent a single bond, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —OCF 2 —, —CF 2 O—, —COO—, —OCO—, or —C≡C—;

m ii1 and m ii2 each independently represent 0, 1, 2, or 3; and

m ii1 +m ii2 is equal to 1, 2, 3, or 4;

in the case where A ii1 and Z ii1 are multiple, the A ii1 moieties and the Z ii1 moieties are the same as or different from each other, respectively; and

in the case where A ii2 and Z ii2 are multiple, the A ii2 moieties and the Z ii2 moieties are the same as or different from each other, respectively,

wherein at least one compound represented by General Formula (ii) in which R ii2 represents a fluorine atom, a trifluoromethyl group, a trifluoromethoxy group, or a cyano group, m ii1 is 0, m ii2 is 3, at least one Z ii2 is —CF 2 O—, and at least one A ii2 represents a 1,4-phenylene group of which at least one hydrogen atom of one 1,4-phenylene group is substituted with a fluorine atom is used.

2. The liquid crystal composition according to claim 1 , further comprising at least one compound represented by General Formula (ii) in which R ii2 represents an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms is used.

3. The liquid crystal composition according to claim 1 , wherein at least one compound represented by General Formula (ii) in which at least one 2,3-difluorobenzene-1,4-diyl group is present is used.

4. The liquid crystal composition according to claim 1 , further comprising a compound represented by General Formula (L)

R L1 —B L1 -L L1 -B L2 L L2 -B L3 OL -R L2   (L)

where R L1 and R L2 each independently represent an alkyl group having 1 to 8 carbon atoms; and one —CH 2 — or at least two —CH 2 — not adjoining each other in the alkyl group are each independently optionally substituted with —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—;

OL represents 0, 1, 2, or 3;

B L1 , B L2 , and B L3 each independently represent a group selected from the group consisting of

(a) a 1,4-cyclohexylene group of which one —CH 2 — or at least two —CH 2 — not adjoining each other are optionally substituted with —O— and

(b) a 1,4-phenylene group of which one —CH═ moiety or at least two —CH═ moieties not adjoining each other are optionally substituted with —N═, and

one and/or at least two hydrogen atoms contained in the groups (a) and (b) are each independently optionally substituted with a cyano group, a fluorine atom, or a chlorine atom;

L L1 and L L2 each independently represent a single bond, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —COO—, —OCO—, —OCF 2 —, —CF 2 O—, —CH═N—N═CH—, —CH═CH—, —CF═CF—, or —C≡C—;

in the case where OL is 2 or 3 and where L L2 is multiple, the L L2 moieties are the same as or different from each other; in the case where OL is 2 or 3 and where B L3 is multiple, the B L3 moieties are the same as or different from each other; and

the compound represented by General Formula (L) excludes the compound represented by General Formula (ii).

5. The liquid crystal composition according to claim 1 , further comprising a compound represented by General Formula (M)

where R M1 represents an alkyl group having 1 to 8 carbon atoms; and one —CH 2 — or at least two —CH 2 — not adjoining each other in the alkyl group are each independently optionally substituted with —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—;

PM represents 0, 1, 2, 3, or 4;

C M1 and C M2 each independently represent a group selected from the group consisting of

(d) a 1,4-cyclohexylene group of which one —CH 2 — or at least two —CH 2 — not adjoining each other are optionally substituted with —O— or —S— and

(e) a 1,4-phenylene group of which one —CH═ moiety or at least two —CH═ moieties not adjoining each other are optionally substituted with —N═, and

one and/or two or more hydrogen atoms contained in the groups (d) and (e) are each independently optionally substituted with a cyano group, a fluorine atom, or a chlorine atom;

K M1 and K M2 each independently represent a single bond, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —OCF 2 —, —CF 2 O—, —COO—, —OCO—, or —C≡C—;

in the case where PM is 2, 3, or 4 and where K M1 is multiple, the K M1 moieties are the same as or different from each other; in the case where PM is 2, 3, or 4 and where C M2 is multiple, the C M2 moieties are the same as or different from each other;

X M1 and X M3 each independently represent a hydrogen atom, a chlorine atom, or a fluorine atom;

X M2 represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, a trifluoromethyl group, a fluoromethoxy group, a difluoromethoxy group, a trifluoromethoxy group, or a 2,2,2-trifluoroethyl group; and the compound represented by General Formula (M) excludes the compound represented by General Formula (ii).

6. The liquid crystal composition according to claim 1 , further comprising a compound represented by General Formula (X″)

where R X1 and R X2 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms; one methylene moiety or at least two methylene moieties not adjoining each other in these groups are optionally substituted with —O— or —S—; at least one hydrogen atom contained in these groups is optionally substituted with a fluorine atom or a chlorine atom;

u and v each independently represent 0, 1, or 2 and satisfy the relationship u+v=2 or less;

M X1 , M X2 , and M X3 each independently represent a group selected from the group consisting of

(a) a trans-1,4-cyclohexylene group of which one methylene moiety or at least two methylene moieties not adjoining each other are optionally substituted with —O— or —S— and

(b) a 1,4-phenylene group of which one —CH═ moiety or at least two —CH═ moieties not adjoining each other are optionally substituted with —N═, and

a hydrogen atom contained in the group (a) or (b) is optionally substituted with a cyano group, a fluorine atom, a trifluoromethyl group, a trifluoromethoxy group, or a chlorine atom; in the case where M X2 and/or M X3 are multiple, the M X2 moieties and/or the M X3 moieties are the same as or different from each other, respectively;

L X1 , L X2 , and L X3 each independently represent a single bond, —COO—, —OCO—, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —OCF 2 —, —CF 2 O—, —CH═CH—, or —C≡C—;

in the case where L X1 and/or L X3 are multiple, the L X1 moieties and/or the L X3 moieties are the same as or different from each other, respectively;

X X1 and X X2 each independently represent a trifluoromethyl group, a trifluoromethoxy group, or a fluorine atom; any one of X X1 and X X2 represents a fluorine atom; and the compound represented by General Formula (X″) excludes the compounds represented by General Formulae (ii) and (L).

7. A liquid crystal display device comprising the liquid crystal composition according to claim 1 .

8. A liquid crystal display device comprising the liquid crystal composition according to claim 1 , wherein the liquid crystal display device operates in an IPS mode, an OCB mode, an ECB mode, a VA mode, a VA-IPS mode, or an FFS mode.