Patent EP-1053996-A1 (EP)
Inventor: HASEBA YASUHIRO
IPC: C09K19/14
Filed: 1999-01-08
Abstract: The present invention is to provide liquid crystalline
compounds suitable for driving at a low voltage and at a wide
temperature range, and are suitable for high speed response, to
provide liquid crystal compositions comprising the compound,
and to provide liquid crystal display devices comprising the
liquid crystal composition;
   the crystalline compounds are ester compounds expressed by
the general formula (1)
 
wherein R 1  represents hydrogen atom, cyano group, nitro group,
amino group, a halogen atom, a straight chain or branched alkyl
group having 1 to 20 carbon atoms, or a straight chain or
branched alkenyl group having 2 to 20 carbon atoms; one or more
hydrogen atoms in these alkyl group and alkenyl group may be
replaced by halogen atoms; one or more -CH 2 - in these alkyl
group and alkenyl group may be replaced by oxygen atoms or
sulfur atoms, but there is no case where oxygen atoms are
adjacent; and one or more carbon atoms in these alkyl group and
alkenyl group may be replaced by silicon atoms;   A 1  to A 5  each independently represent 1,4-cyclohexylene, 1,4-phenylene,
1-cyclohexene-1,4-diyl, 3-cyclohexene-1,4-diyl, 1-sila-1,4-cyclohexylene,
or 4-sila-1,4-cyclohexylene; one or more
-CH 2 - in the 1,4-cyclohexylene, 1-cyclohexene-1,4-diyl, and 3-cyclohexene-1,4-diyl
may each independently be replaced by 
oxygen atoms, sulfur atoms, -CO-, -CS-, SiH 2 -, -NH-, -CF 2 -, or
-CFH-, but there is no case where oxygen atoms are adjacent;
hydrogen atoms which bond to carbon atoms at position 2 and
position 3, respectively, in the 1-cyclohexene-1,4-diyl or 3-cyclohexene-1,4-diyl
may each independently be replaced by
fluorine atoms; one or more hydrogen atoms in the 1,4-phenylene
may each independently be replaced by halogen atoms, halogenated
alkyl groups having 1 to 3 carbon atoms, methyl groups, cyano
groups, or nitro groups; and one or more -CH= in the 1,4-phenylene
may each independently be replaced by nitrogen atoms;   bonding groups Za to Zd each independently represent single
bond, -CH 2 -, -O-, -C≡C-, or an alkylene group or alkenylene
group having 2 to 4 carbon atoms; one or more hydrogen atoms in
these groups may be replaced by halogen atoms; and -CH 2 - in
these groups may each independently be replaced by oxygen atom,
sulfur atom, -CO-, -CS-, -NH-, -CF 2 -, or -CFH-, but there is no
case where oxygen atoms are adjacent;   bonding group Ze represents single bond, an alkylene group
or alkenylene group having 1 to 10 carbon atoms; and -CH 2 - in
these groups may each independently be replaced by oxygen atom,
sulfur atom, -CO-, -CF 2 -, -CFH-, -CH=CH-, -CF=CF-, -CF=CH-, or
-C≡C-, but there is no case where oxygen atoms are adjacent;   n1 to n3 are each independently 0 or 1, but n1 ≦ n2 ≦ n3;   Y 1  and Y 2  each independently represent oxygen atom or sulfur
atom;   R 2  represents a halogen atom, a straight chain or branched
alkyl group having 1 to 20 carbon atoms, or straight chain or 
branched alkenyl group having 2 to 20 carbon atoms, one or more
hydrogen atoms in these alkyl group and alkenyl group are
replaced by halogen atoms; one or more -CH 2 - in these groups may
be replaced by oxygen atoms or sulfur atoms, but there is no
case where oxygen atoms are adjacent; and one or more carbon
atoms in these groups may be replaced by silicon atoms;   provided that when A 5  represents unsubstituted 1,4-phenylene
in this compound, then Zd is single bond, and A 4  is not 1,4-phenylene;
and   each atom which constitutes this compound may be replaced by
its isotope.