Liquid crystal compound, liquid crystal composition, composite material with encapsulated liquid crystal, and liquid crystal display device using same

A compound, represented by formula (1):

• MG1-Za-Sp-Zb-MG2 (1)
• wherein, in formula (1), MG1 and MG2 are each independently a mesogenic group;
• Za and Zb are independently a single bond or alkylene having 1 to 4 carbons, and in the Za and the Zb, at least one piece of —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one piece of —(CH2)2— may be replaced by —CH═CH— or —C≡C—, and at least one piece of hydrogen may be replaced by fluorine;
• Sp has an achiral structure represented by formula (sp-1):
• -α-X-α- (sp-1)
• wherein, in formula (sp-1), α is each independently straight-chain alkylene having 1 to 20 carbons, and in the α, at least one piece of —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one piece of —(CH2)2— may be replaced by —CH═CH— or —C≡C—, and at least one piece of hydrogen may be replaced by fluorine;
• X is represented by formula (I), formula (II) or formula (III):
• wherein, in formula (I), Ra is a hydroxyl group or alkyl having 1 to 10 carbons, and in the Ra, at least one piece of —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one piece of —(CH2)2— may be replaced by —CH═CH— or —C≡C—, and at least one piece of hydrogen may be replaced by fluorine;
• in formula (II), Rb and Rc are each independently fluorine, chlorine or alkyl having 1 to 10 carbons, and in the Rb and the Rc, at least one piece of —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one piece of —(CH2)2— may be replace by —CH═CH— or —C≡C—, and at least one piece of hydrogen may be replaced by fluorine;
• and
• in formula (III), Q is an oxygen atom, a sulfur atom or alkylidene having 1 to 10 carbons, and in the Q, at least one piece of —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one piece of —(CH2)2— may be replaced by —CH═CH— or —C≡C—, and at least one piece of hydrogen may be replaced by fluorine.