Alkenyl cyclohexane derivatives and liquid crystal compositions

Claim 2

A liquid crystalline compound of formula (I) ##STR1965## wherein R 1 is an alkyl group of 1-15 carbons, an alkenyl group of 2-15 carbons or an alkyl or alkenyl group in which one or plural non-adjacent methylene groups (--CH 2 --) is or are replaced by --O--, --S--, --C.tbd.C--! or --COO--, R 2 is a hydrogen atom or an alkyl group of 1-10 carbons; m is 0-5; when m is 2 or more, one methylene group or plural non-adjacent methylene groups in --(CH 2 ) m -- may be replaced by --O--; and the rings A 1 , A 2 and A 3 are independently a 1,4-cyclohexylene group, a cyclohexene-1,4-diyl group a 1,3-dioxane-2,5, diyl group, a tetrahydropyrane-2,5, diyl group, a 1,3-dithian-2,5-diyl group or a tetrahydrothiopyrane-2,5-diyl group, provided A 3 is not a 1,3-dioxane-2,5-diyl group when A 2 is a 1,4-cyclohexylene group and no methylene group in --(CH 2 ) m -- may be replaced by --O-- when rings A1, A2 and A3 are all 1,4-cyclohexylene groups.

Claim 3

The liquid crystalline compound of claim 1 wherein m is 0.

Claim 4

The liquid crystalline compound of claim 1 wherein m is 2.

Claim 5

The liquid crystalline compound of claim 2 wherein R 1 is an alkenyl group.

Claim 6

The liquid crystalline compound of claim 3 wherein R 1 is an alkenyl group.

Claim 7

A liquid crystal composition which comprises at least one of the liquid crystalline compounds set forth in any one of claims 1-5.

Claim 8

A liquid crystal composition which comprises: (i) as a first component, at least one of the liquid crystalline compounds set forth in any one of claims 1-5, and (ii) as a second component, at least one compound selected from the group consisting of the compounds of formulae (II-a), (II-b) and (II-c) ##STR1966## wherein R 3 is an alkyl group of 1-10 carbons, X 1 is F, Cl, OCF 3 , OCF 2 H, CF 3 , CF 2 H or CFH 2 , L 1 , L 2 , L 3 and L 4 are independently H or F, Z 1 and Z 2 are independently --(CH 2 ) 2 --, --CH═CH-- or a covalent bond and a is 1 or 2.

Claim 9

A liquid crystal composition which comprises: (i) as a first component, at least one of the liquid crystalline compounds set forth in any one of claims 1-5, (ii) as a second component, at least one compound selected from the group consisting of the compounds of formulae (III-a), (III-b), (III-c), (III-d) and (III-e) ##STR1967## wherein R 4 is F, an alkyl group of 1-10 carbons or an alkenyl group of 2-10 carbons, the methylene group (--CH 2 --) in said alkyl or alkenyl group may be replaced by an oxygen atom (--O--) provided that two or more methylene groups in series are not replaced by an oxygen atom, the ring A is a trans-1,4-cyclohexylene, 1,4-phenylene, pyrimidine-2,5-diyl or 1,3-dioxane-2,5-diyl group, the ring B is a trans-1,4-cyclohexylene, 1,4-phenylene or pyrimidine-2,5-diyl group, the ring C is a trans-1,4-cyclohexylene or 1,4-phenylene group, Z 3 is --(CH 2 ) 2 --, --COO-- or a covalent bond, L 5 and L 6 are independently H or F, and b and c are independently 0 or 1, ##STR1968## wherein R 5 is an alkyl group of 1-10 carbons, L 7 is H or F and d is 0 or 1, ##STR1969## wherein R 6 is an alkyl group of 1-10 carbons, the rings D and E are independently a trans-1,4-cyclohexylene or 1,4-phenylene group, Z 4 and Z 5 are independently --COO-- or a covalent bond, Z 6 is --COO-- or --C.tbd.C--, L 8 and L 9 are independently H or F, X 2 is F, OCF 3 , OCF 2 H, CF 3 , CF 2 H or CFH 2 , provided that when X 2 is OCF 3 , OCF 2 H, CF 3 , CF 2 H or CFH 2 , both L 8 and L 9 represent a hydrogen atom, and e, f and g are independently 0 or 1, ##STR1970## wherein R 7 and R 8 are independently an alkyl group of 1-10 carbons or an alkenyl group of 2-10 carbons, the methylene group (--CH 2 --) in said alkyl or alkenyl group may be replaced by an oxygen atom (--O--) provided that two or more methylene groups in series are not replaced by an oxygen atom, the ring G is a trans-1,4-cyclohexylene, 1,4-phenylene or pyrimidine-2,5-diyl group, the ring H is a trans-1,4-cyclohexylene or 1,4-phenylene group, Z 7 is --C.tbd.C--, --COO--, --(CH 2 ) 2 --, --CH═CH--C.tbd.C-- or a covalent bond, and Z 8 is --COO or a covalent bond, ##STR1971## wherein R 9 and R 10 are independently an alkyl group of 1-10 carbons or an alkenyl group of 2-10 carbons, the methylene group (--CH 2 --) in said alkyl or alkenyl group may be replaced by an oxygen atom (--O--) provided that two or more methylene groups in series are not replaced by an oxygen atom, the ring I is a trans-1,4-cyclohexylene, 1,4-phenylene or pyrimidine-2,5-diyl group, the ring J is a trans-1,4-cyclohexylene group, a 1,4-phenylene or pyrimidine-2,5-diyl group in which one or more hydrogen atoms on the ring may be substituted by F, the ring K is a trans-1,4-cyclohexylene or 1,4-phenylene group, Z 9 and Z 11 are independently --COO--, --(CH 2 ) 2 --, or a covalent bond, Z 10 is --CH═CH--, --C.tbd.C--, --COO-- or a covalent bond and h is 0 or 1.

Claim 10

The liquid crystal composition of claim 8, further comprising at least one compound selected from the group consisting of the compounds of formulae II-a, II-b and II-c: ##STR1972## wherein R 3 is an alkyl group of 1-10 carbons, X 1 is F, Cl, OCF 3 , OCF 2 H, CF 3 , CF 2 H, or CFH 2 , L 1 , L 2 , L 3 and L 4 are independently H or F, Z 1 and Z 2 are independently --(CH 2 ) 2 --, --CH═CH-- or a covalent bond and a is 1 or 2.

Claim 11

A liquid crystal display element comprising the liquid crystal compound set forth in any one of claims 1-5.

Claim 12

A liquid crystal display element comprising the liquid crystal composition set forth in claim 7.

Claim 13

A liquid crystal display element comprising the liquid crystal composition set forth in claim 8.

Claim 14

A liquid crystal display element comprising the liquid crystal composition set forth in claim 9.

Claim 15

The liquid crystal compound of claim 1, wherein rings A 1 , A 2 and A 3 cannot each be a 1,4-cyclohexylene group at the same time.