Polymerizable compound as well as liquid crystal composition and liquid crystal display device each including polymerizable compound

1. A compound represented by a general formula (i):

wherein

R i1 denotes a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, or a halogenated alkyl group having 1 to 30 carbon atoms, —CH 2 — in the alkyl or halogenated alkyl group is optionally replaced with —CH═CH—, —C≡—, —O—, —NH—, —COO—, —OCO—, or —OCOO—, but —O— is not adjacent to another —O—,

R i2 denotes a linear alkyl group having 2 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear halogenated alkyl group having 2 to 10 carbon atoms, or a branched halogenated alkyl group having 3 to 10 carbon atoms, wherein —CH 2 — in the alkyl or halogenated alkyl group is optionally replaced with —CH═CH—, —O—, —COO—, or —OCO—, but —O— is not adjacent to another —O—,

a ring A denotes a divalent aromatic group, a divalent alicyclic group, a divalent heterocyclic compound group, a divalent fused ring, or a divalent fused polycyclic ring, a hydrogen atom in these ring structures is optionally replaced with L i1 , L i1 denotes a halogen atom, a cyano group, a nitro group, P-Sp-, a monovalent organic group having a group represented by a general formula K i1 , a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear halogenated alkyl group having 1 to 10 carbon atoms, or a branched halogenated alkyl group having 3 to 10 carbon atoms, wherein —CH 2 — in the alkyl or halogenated alkyl group is optionally replaced with —CH═CH—, —C≡C—, —O—, —NH—, —COO—, —OCO—, or —OCOO—, but —O— is not adjacent to another —O—,

a ring B denotes a formula (B-1),

wherein a hydrogen atom in the ring B is optionally replaced with L i2 , L i2 denotes a halogen atom, a monovalent organic group having a group represented by the general formula K i1 , a linear alkyl group having 1 to 10 carbon atoms, wherein—CH 2 — in the alkyl or halogenated alkyl group is optionally replaced with —CH═CH—, —C≡—, —O—, —COO—, or —OCO—, but —O— is not adjacent to another —O—,

Z i1 denotes a single bond, —O—, —CH═CH—, —CF═CF—, —C≡C—, —COO—, —OCO—, —OCOO—, —CF 2 O—, —OCF 2 —, —CH═CHCOO—, —OCOCH═CH—, —CH═C(CH 3 )COO—, —OCOC(CH 3 )═CH—, —CH 2 —CH(CH 3 )COO—, —OCOCH(CH 3 )—CH 2 —, —OCH 2 CH 2 O—, or an alkylene group having 2 to 10 carbon atoms, and one —CH 2 — or two or more nonadjacent —CH 2 — groups in the alkylene group are optionally replaced with —O—, —COO—, or —OCO—,

Z i3 denotes a single bond, —O—, —CH═CH—, —COO—, —OCO—, —OCOO—, —CH═CHCOO—, —OCOCH═CH—, —CH═C(CH 3 )COO—, —OCOC(CH 3 )═CH—, —CH 2 —CH(CH 3 )COO—, —OCOCH(CH 3 )—CH 2 —, or a linear alkylene group having 2 to 20 carbon atoms, a branched alkylene group having 3 to 20 carbon atoms, one —CH 2 — or two or more nonadjacent —CH 2 — groups in the alkylene group are optionally replaced with —O—, —COO—, or —OCO—,

K i1 denotes a group represented by one of general formulae (K-1) to (K-6),

R K1 denotes a hydrogen atom, a linear alkyl group having 1 to 6 carbon atoms, or a alkyl group having 3 to 6 carbon atoms, and T K1 independently denotes a group represented by one of general formulae (T-1) to (T-6),

S T1 denotes a single bond, a linear alkylene group having 1 to 15 carbon atoms, a branched alkylene group having 3 to 15 carbon atoms, a linear alkenylene group having 2 to 18 carbon atoms, or a branched alkenylene group having 3 to 18 carbon atoms, wherein —CH 2 — in the alkylene or alkelene group is optionally replaced with —O—, —COO—, —C(═O)—, —C(═CH 2 )—, or —OCO— such that oxygen atoms are not directly adjacent to each other, R T1 denotes an alkyl group having 1 to 5 carbon atoms, —CH 2 — in the alkyl group is optionally replaced with —O—, —COO—, —C(═O)—, —C(═CH 2 )—, or —OCO— such that oxygen atoms are not directly adjacent to each other, and R T2 and R T3 independently denote a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and

P denotes a polymerizable group, Sp denotes a spacer group or a single bond, m denotes an integer in the range of 1 to 4, a plurality of As, if present, may be the same or different, a plurality of Z i1 s, if present, may be the same or different, a plurality of Ps, if present, may be the same or different, and a plurality of Sps, if present, may be the same or different.

2. The compound according to claim 1 , wherein A in the general formula (i) denotes a ring structure selected from a 1,4-phenylene group, a 1,4-cyclohexylene group, an anthracene-2,6-diyl group, a phenanthrene-2,7-diyl group, a pyridine-2,5-diyl group, a pyrimidine-2,5-diyl group, a naphthalene-2,6-diyl group, an indan-2,5-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, and a 1,3-dioxane-2,5-diyl group, and the ring structure is unsubstituted or denotes a group optionally substituted with an alkyl group having 1 to 12 carbon atoms, a halogenated alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a halogenated alkoxy group having 1 to 12 carbon atoms, a halogen atom, a cyano group, a nitro group, or P-Sp-.

3. The compound according to claim 1 , wherein P in the general formula (i) denotes a substituent selected from a group represented by the following general formulae (P-1) to (P-14).

4. The compound according to claim 1 , wherein K i1 in the general formula (i) is represented by the general formula (K-1) or (K-2).

5. A liquid crystal composition comprising: a compound represented by the general formula (i) according to claim 1 ; a polymerizable compound different from the compound represented by the general formula (i); and a nonpolymerizable liquid crystal compound.

6. The liquid crystal composition according to claim 5 , wherein the polymerizable compound is one or two or more compounds represented by a general formula (P):

wherein

Z p1 denotes a fluorine atom, a cyano group, a hydrogen atom, an alkyl group having 1 to 15 carbon atoms in which a hydrogen atom is optionally replaced with a halogen atom, an alkoxy group having 1 to 15 carbon atoms in which a hydrogen atom is optionally replaced with a halogen atom, an alkenyl group having 2 to 15 carbon atoms in which a hydrogen atom is optionally replaced with a halogen atom, an alkenyloxy group having 2 to 15 carbon atoms in which a hydrogen atom is optionally replaced with a halogen atom, or -Sp p2 -R p2 ,

R p1 and R p2 denote one of the following formulae (R-I) to (R-VIII),

wherein

* is bonded to Sp p1 ,

R 2 to R 6 independently denote a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms,

W denotes a single bond, —O—, or a methylene group,

T denotes a single bond or —COO—, and

p, t, and q independently denote 0, 1, or 2,

Sp p1 and Sp p2 denote a spacer group,

L p1 and L p2 independently denote a single bond, —O—, —S—, —CH 2 —, —OCH 2 —, —CH 2 O—, —CO—, —C 2 H 4 —, —COO—, —OCO—, —OCOOCH 2 —, —CH 2 OCOO—, —OCH 2 CH 2 O—, —CO—NR a —, —NR a —CO—, —SCH 2 —, —CH 2 S—, —CH═CR a —COO—, —CH═CR a —OCO—, —COO—CR a ═CH—, —OCO—CR a ═CH—, —COO—CR a ═CH—COO—, —COO—CR a ═CH—OCO—, —OCO—CR a ═CH—COO—, —OCO—CR a ═CH—OCO—, —(CH 2 ) z —C(═O)—O—, —(CH 2 ) z —O—(C═O)—, —O—(C═O)—(CH 2 ) z —, —(C═O)—O—(CH 2 ) z —, —CH 2 (CH 3 )C—C(═O)—O—, —CH 2 (CH 3 )C—O—(C═O)—, —O—(C═O)—C(CH 3 )CH 2 , —(C═O)—O—C(CH 3 )—CH 2 , —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—, —CF 2 —, —CF 2 O—, —OCF 2 —, —CF 2 CH 2 —, —CH 2 CF 2 —, —CF 2 CF 2 —, or —C≡C— (wherein R a independently denotes a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and z denotes an integer in the range of 1 to 4,

M p2 denotes a 1,4-phenylene group, a 1,4-cyclohexylene group, an anthracene-2,6-diyl group, a phenanthrene-2,7-diyl group, a pyridine-2,5-diyl group, a pyrimidine-2,5-diyl group, a naphthalene-2,6-diyl group, an indan-2,5-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a 1,3-dioxane-2,5-diyl group, or a single bond, M p2 is unsubstituted or optionally substituted with an alkyl group having 1 to 12 carbon atoms, a halogenated alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a halogenated alkoxy group having 1 to 12 carbon atoms, a halogen atom, a cyano group, a nitro group, or —R p1 ,

M p1 denotes one of the following formulae (i-11) to (ix-11),

wherein * is bonded to Sp p1 , and ** is bonded to L p1 , L p2 , or Z p1 ,

M p3 denotes one of the following formulae (i-13) to (ix-13),

wherein * is bonded to Z p1 , and ** is bonded to L p2 ,

m p2 to m p4 independently denote 0, 1, 2, or 3,

m p1 and m p5 independently denote 1, 2, or 3, and

a plurality of Z p1 s, if present, may be the same or different, a plurality of R p1 s, if present, may be the same or different, a plurality of R p2 s, if present, may be the same or different, a plurality of Sp p1 s, if present, may be the same or different, a plurality of Sp p2 s, if present, may be the same or different, a plurality of L p1 s, if present, may be the same or different, and a plurality of M p2 s, if present, may be the same or different.

7. A liquid crystal display device in which at least one of two substrates with the liquid crystal compositions according to claim 5 has no alignment film.