Liquid crystal composition and liquid crystal display element

A liquid crystal composition comprising a first component which is at least one member selected from the group consisting of compounds expressed by the formulae (I-a) and (I-b)

• wherein R1 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• and n denotes 0 to 20,
• a second component which is at least one member selected from the group consisting of compounds expressed by the formulae II-a, II-b, II-c and II-d
• wherein R1 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• and n denotes 0 to 20,
• a third component which is at least one member selected from the group consisting of compounds expressed by the formulae III-a, III-b and III-c
• wherein R2 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• Z0 denotes —COO— or —CH2CH2—;
• Z1 denotes —CH2CH2—, —COO— or a single bond;
• Q1 denotes H or F;
• A1 denotes trans-1,4-cyclohexylene, 1,4-phenylene or 1,3-dioxane-2,5-diyl;
• A2 and A3 each independently denote trans-1,4-cyclohexylene or 1,4-phenylene;
• and p, q and m each independently denote 0 or 1, and
• a fourth component which is at least one member selected from the group consisting of compounds expressed by the formulae IV, V, VI-a and VI-b
• R3-(B)-Z2-(C)-R4 (IV)
• wherein R1 and R4 each independently denote an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• B denotes trans-1,4-cyclohexylene, pyrimidine-2,5-diyl or 1,4-phenylene;
• C denotes trans-1,4-cyclohexylene or 1,4-phenylene;
• and Z2 denotes —C≡C—, —COO—, —CH2CH2—, —CH═CH—, —CF═CF— or a single bond,
• R5-(D)-Z3-(E)-Z4-(G)-R6 (V)
• wherein R5 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• R6 denotes an alkyl group, an alkoxy group or an alkoxymethyl group having from 1 to 10 carbon atoms;
• D denotes trans-1,4-cyclohexylene or pyrimidine-2,5-diyl;
• E denotes trans-1,4-cyclohexylene or 1,4-phenylene in which one H at a 2-, 3-, 5- or 6-position may be optionally replaced by F;
• G denotes trans-1,4-cyclohexylene or 1,4-phenylene;
• Z3 denotes —CH2CH2 or a single bond;
• and Z4 denotes —C≡C—, —COO—, —CH═CH— or a single bond,
• wherein R7 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• R8 denotes an alkyl group, an alkoxy group or an alkoxymethyl group having from 1 to 10 carbon atoms;
• and Q2 denotes H or F.

A liquid crystal composition comprising a first component which is at least one member selected from the group consisting of compounds expressed by the formulae (I-a) and (I-b)

• wherein R1 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• and n denotes 0 to 20,
• a second component which is at least one member selected from the group consisting of compounds expressed by the formulae II-a, II-b, II-c and II-d
• wherein R1 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• and n denotes 0 to 20,
• a third component which is at least one member selected from the group consisting of compounds expressed by the formulae III-a, III-B and III-c
• wherein R2 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• Z0 denotes —COO— or —CH2CH2—;
• Z1 denotes —CH2CH2—, —COO— or a single bond;
• Q1 denotes H or F;
• A1 denotes trans-1,4-cyclohexylene, 1,4-phenylene or 1,3-dioxane-2,5-diyl;
• A2 and A3 each independently denote trans-1,4-cyclohexylene or 1,4-phenylene;
• and p, q and m each independently denote 0 or 1,
• a fourth component which is at least one member selected from the group consisting of compounds expressed by the formulae IV, V, VI-a and VI-b
• R3-(B)-Z2-(C)-R4 (IV)
• wherein R3 and R4 each independently denote an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• B denotes trans-1,4-cyclohexylene, pyrimidine-2,5-diyl or 1,4-phenylene;
• C denotes trans-1,4-cyclohexylene or 1,4-phenylene;
• and Z2 denotes —C≡C—, —COO—, —CH2CH2—, —CH═CH—, —CF═CF— or a single bond,
• R5-(D)-Z3-(E)-Z4-(G)-R6 (V)
• wherein R5 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• R6 denotes an alkyl group, an alkoxy group or an alkoxymethyl group having from 1 to 10 carbon atoms;
• D denotes trans-1,4-cyclohexylene or pyrimidine-2,5-diyl;
• E denotes trans-1,4-cyclohexylene or 1,4-phenylene in which one H at a 2-, 3-, 5- or 6-position may be optionally replaced by F;
• G denotes trans-1,4-cyclohexylene or 1,4-phenylene;
• Z3 denotes —CH2CH2— or a single bond;
• and Z4 denotes —C≡C—, —COO—, —CH═CH— or a single bond,
• wherein R7 denotes an alkyl group having from 1 to 10 carbon atoms wherein one CH2 group may be replaced by oxygen atom or —CH═CH— group;
• R8 denotes an alkyl group, an alkoxy group or an alkoxymethyl group having from 1 to 10 carbon atoms;
• and Q2 denotes H or F, and
• a fifth component which is at least one member selected from the group consisting of compounds expressed by the formulae VII and VIII
• wherein R9 denotes an alkyl group having from 1 to 10 carbon atoms;
• Q3 denotes H or F:
• and k denotes 0 or 1,
• wherein R10 denotes an alkyl group having from 1 to 10 carbon atoms;
• J denotes trans-1,4-cyclohexylene or 1,4-phenylene;
• Q4 and Q5 each independently denote H or F;
• Z5 and Z6 each independently denote —COO— or a single bond;
• and h denotes 0, 1 or 2.