Positive dielectric anisotropy liquid crystal compositions

Claim 2

A liquid crystal composition of high positive dielectric anisotropy formed of a mixture of seven nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC5## the mixture consisting of the specific compounds given in the following table as to the specific substituents of each compound thereof: in which the first five, nitrile-containing, compounds together constitute at least one-half by weight of the entire mixture ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.5 H.sub.11 CN 2 C.sub.7 H.sub.15 CN 3 C.sub.8 H.sub.17 CN 4 C.sub.6 H.sub.13 O CN 5 C.sub.7 H.sub.15 O CN O ∥ 6 C.sub.4 H.sub.9 OCO OC.sub.2 H.sub.5 7 CH.sub.3 O C.sub.5 H.sub.11 ______________________________________

Claim 3

A liquid crystal composition according to claim 1, in which: each compound is present in an amount between 5% and 25% of the total mixture, by weight.

Claim 4

A liquid crystal composition according to claim 2, in which: the seven compounds are present in approximately the following respective weight percentages: ______________________________________ COMPOUND NUMBER PERCENT BY WEIGHT ______________________________________ 1 15% 2 21% 3 20% 4 9% 5 7% 6 15% 7 13% ______________________________________

Claim 5

said composition having a mesophasic range from about +5°C to about +60°C.

Claim 6

said composition having a mesophasic range from about +5°C to about +60°C.

Claim 7

A liquid crystal composition of high positive dielectric anisotropy formed of a mixture of eight nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC6## the mixture consisting of the specific compounds given in the following table as to specific substituents of each compound thereof in which the first five, nitrile-containing, compounds together constitute at least one-half by weight of the entire mixture: ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.5 H.sub.11 CN 2 C.sub.7 H.sub.15 CN 3 C.sub.8 H.sub.17 CN 4 C.sub.6 H.sub.13 O CN 5 C.sub.7 H.sub.15 O CN 6 ##STR4## OC.sub.2 H.sub.5 7 CH.sub.3 O C.sub.5 H.sub.11 8 C.sub.5 H.sub.11 O OC.sub.6 H.sub.13 ______________________________________

Claim 8

A liquid crystal composition of high positive dielectric anisotropy formed of a mixture of eight nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC6## the mixture consisting of the specific compounds given in the following table as to specific substituents of each compound thereof in which the first five, nitrile-containing, compounds together constitute at least one-half by weight of the entire mixture: ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.5 H.sub.11 CN 2 C.sub.7 H.sub.15 CN 3 C.sub.8 H.sub.17 CN 4 C.sub.6 H.sub.13 O CN 5 C.sub.7 H.sub.15 O CN 6 ##STR4## OC.sub.2 H.sub.5 7 CH.sub.3 O C.sub.5 H.sub.11 8 C.sub.5 H.sub.11 O OC.sub.6 H.sub.13 ______________________________________

Claim 9

A liquid crystal composition according to claim 4, in which: each compound is present in an amount between 5% and 25% of the total mixture, by weight.

Claim 10

A liquid crystal composition according to claim 5, in which: the eight compounds are present in approximately the following respective weight percentages: ______________________________________ COMPOUND NUMBER PERCENT BY WEIGHT ______________________________________ 1 7 1/2% 2 21% 3 20% 4 9% 5 7% 6 15% 7 13% 8 7 1/2% ______________________________________ said compositions having a mesophasic range from about +2°C to about +62°C.

Claim 11

A liquid crystal composition of high positive dielectric anisotropy formed of a mixture of seven nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC7## the mixture consisting of the specific compounds given in the following table as to specific substituents of each compounds thereof in which the first four, nitrile-containing, compounds together constitute at least one-half by weight of the entire mixture: ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.7 H.sub.15 CN 2 C.sub.8 H.sub.17 CN 3 C.sub.6 H.sub.13 O CN 4 C.sub.7 H.sub.15 O CN 5 ##STR5## OC.sub.5 H.sub.5 6 CH.sub.3 O C.sub.5 H.sub.11 7 C.sub.5 H.sub.11 O OC.sub.6 H.sub.13 ______________________________________

Claim 12

A liquid crystal composition of high positive dielectric anisotropy formed of a mixture of seven nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC7## the mixture consisting of the specific compounds given in the following table as to specific substituents of each compounds thereof in which the first four, nitrile-containing, compounds together constitute at least one-half by weight of the entire mixture: ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.7 H.sub.15 CN 2 C.sub.8 H.sub.17 CN 3 C.sub.6 H.sub.13 O CN 4 C.sub.7 H.sub.15 O CN 5 ##STR5## OC.sub.5 H.sub.5 6 CH.sub.3 O C.sub.5 H.sub.11 7 C.sub.5 H.sub.11 O OC.sub.6 H.sub.13 ______________________________________

Claim 13

A liquid crystal composition according to claim 7, in which: each compound is present in an amount between 5% and 25% of the total mixture, by weight.

Claim 14

A liquid crystal composition according to claim 8, in which: the seven compounds are present in approximately the following respective weight percentages: ______________________________________ COMPOUND NUMBER PERCENT BY WEIGHT ______________________________________ 1 21% 2 20% 3 9% 4 7% 5 15% 6 13% 7 15% ______________________________________

Claim 15

said composition having a mesophasic range from about -2°C to about +63°C.

Claim 16

said composition having a mesophasic range from about -2°C to about +63°C.

Claim 17

A liquid crystal composition of high positive dielectric anisotropy formed of: a sub-mixture of a plurality of the group of five nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC8## said sub-mixture consisting of the specific compounds given in the following table as to specific substituents of each compound thereof in which the first four, nitrile-containing, compounds together constitute at least one-half by weight of the sub-mixture and at least one-third by weight of the entire composition: ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.7 H.sub.15 CN 2 C.sub.8 H.sub.17 CN 3 C.sub.6 H.sub.13 O CN 4 C.sub.7 H.sub.15 O CN O ∥ 5 C.sub.4 H.sub.9 OCO OC.sub.2 H.sub.5 ______________________________________

Claim 18

A liquid crystal composition of high positive dielectric anisotropy formed of: a sub-mixture of a plurality of the group of five nematic liquid compounds, each compound corresponding to a general chemical formula: ##SPC8## said sub-mixture consisting of the specific compounds given in the following table as to specific substituents of each compound thereof in which the first four, nitrile-containing, compounds together constitute at least one-half by weight of the sub-mixture and at least one-third by weight of the entire composition: ______________________________________ COMPOUND NUMBER X Y ______________________________________ 1 C.sub.7 H.sub.15 CN 2 C.sub.8 H.sub.17 CN 3 C.sub.6 H.sub.13 O CN 4 C.sub.7 H.sub.15 O CN O ∥ 5 C.sub.4 H.sub.9 OCO OC.sub.2 H.sub.5 ______________________________________

Claim 19

and a double-ester nematic liquid compound having a chemical formula: ##SPC9##

Claim 20

and a double-ester nematic liquid compound having a chemical formula: ##SPC9##

Claim 21

A liquid crystal composition according to claim 10, in which: the six compounds are present in approximately the following respective weight percentages: ______________________________________ COMPOUND NUMBER PERCENT BY WEIGHT ______________________________________ 1 14% 2 26% 3 5% 4 5% 5 10% 6 40% ______________________________________

Claim 22

said compositions having a mesophasic range from about +5°C to about +80°C.

Claim 23

said compositions having a mesophasic range from about +5°C to about +80°C.