Liquid crystal device

Claim 2

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide which has a fluorine-containing substituent in its diamine-originated moiety.

Claim 3

A device according to Claim 1, wherein said fluorine-containing substituent is a fluoroalkyl group.

Claim 4

A device according to Claim 1, wherein said diamine-originated moiety comprises a recurring unit represented by the following structural formula (I): wherein R.. denotes an arylene group which may have a substituent.

Claim 5

A device according to Claim 1, wherein said diamine-originated moiety comprises a recurring unit represented by the following structural formula (II): wherein R 2 . denotes or -S0 2 -; and R 22 , R 23 and R 24 respectively denote -CF 3 , -CH 3 or -H with proviso that at least one of R 2 - R 24 is a fluorine-containing substituent.

Claim 6

A device according to Claim 1, wherein said polyimide film has been subjected to a uniaxial aligning treatment.

Claim 7

A device according to Claim 5, wherein said uniaxial aligning treatment is rubbing.

Claim 8

A device according to Claim 5, wherein said polyimide film subjected to a uniaxial aligning treatment is disposed by the medium of an insulating film on an electrode which is in turn disposed on a substrate.

Claim 9

A device according to Claim 7, wherein said polyimide film has a thickness of 50 - 1000 Å. and said insulating film has a thickness of 200 - 1000 A.

Claim 10

A device according to Claim 7, wherein said polyimide film has a thickness of 100 A or less.

Claim 11

A device according to Claim 1, wherein said pair of substrates are disposed to have a spacing small enough to suppress the formation of a helical alignment structure of the chiral smectic liquid crystal.

Claim 12

A device according to Claim 10. wherein said chiral smectic liquid crystal has been cooled from a temperature higher than a range giving smectic A phase to form at least two different stable orientation states.

Claim 13

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide which has at least one structural unit represented by the following formula (III) - (VI) and also a structural unit represented by the following formula (Vll):

Claim 14

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide which has at least one structural unit represented by the following formula (III) - (VI) and also a structural unit represented by the following formula (Vll):

Claim 15

A device according to Claim 12, wherein said polyimide film has been subjected to a uniaxial aligning treatment.

Claim 16

A device according to Claim 12, wherein said uniaxial aligning treatment is rubbing.

Claim 17

A device according to Claim 12, wherein said polyimide film subjected to a uniaxial aligning treatment is disposed by the medium of an insulating film on an electrode which is in turn disposed on a substrate.

Claim 18

A device according to Claim 15, wherein said polyimide film has a thickness of 50 - 1000 A, and said insulating film has a thickness of 200 - 1000 A.

Claim 19

A device according to Claim 15, wherein said polyimide film has a thickness of 100 A or less.

Claim 20

A device according to Claim 12, wherein said pair of substrates are disposed to have a spacing small enough to suppress the formation of a helical alignment structure of the chiral smectic liquid crystal.

Claim 21

A device according to Claim 18, wherein said chiral smectic liquid crystal has been cooled from a temperature higher than a range giving smectic A phase to form at least two different stable orientation states.

Claim 22

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide which has a fluorine-containing substituent in both its diamine-originated moiety and carboxylic acid-originated moiety.

Claim 23

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide which has a fluorine-containing substituent in both its diamine-originated moiety and carboxylic acid-originated moiety.

Claim 24

A device according to Claim 20, wherein said fluorine-containing substituent is a fluoroalkyl group.

Claim 25

A device according to Claim 20, wherein said carboxylic acid-originated moiety has been derived from a fluorine-containing tetracarboxylic acid anhydride.

Claim 26

A device according to Claim 22, wherein said fluorine-containing tetracarboxylic acid is selected from the group consisting of: 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]hexafluoropropane, 2,2-bis(3-4-dicarboxyphenyl)hexafluoropropane, bis(3,4-dicarboxyphenyl)hexafluoropropane, 4,4'-bis[4-(3,4-dicarbox- yphenoxy)phenyl]hexafluoropropane, (trifluoromethyl)pyromellitic acid, bis(trifluoromethyl)pyromellitic acid, 5,5'-bis(trifluoromethyl)3,3',4,4'-tetracarboxybiphenyl, 2,2 5,5 -tetrakis(trifluoromethyl)-3,3 ,4,4'-tetracarboxybiphenyl, 5,5'-bis(trifluoromethyl)-3,3',4,4'-tetracarboxydiphenyl ether, 5,5'-bis(trifluoromethyl)-3,3',4,4'-tetracarboxybenzophenone, bis[(trifluoromethyl)dicarboxyphenoxy]benzene, bis[(trifluoromethyl)-dicarboxyphenoxy]biphenyl, bis[(trifluoromethyl)dicarboxyphenoxy](trifluoromethyl)benzene, bis[-(trifluoromethyl)dicarboxyphenoxy)bis(trifluoromethyl)biphenyl, bis[(trifluoromethyl)dicarboxyphenoxy]-diphenyl ether, bis(dicarboxyphenoxy)(trifluoromethyl)benzene, bis(dicarboxyphenoxy)bis(trifluoromethyl)-benzene, bis(dicarboxyphenoxy)tetrakis(trifluoromethyl)benzene, bis(dicarboxypenoxy)bis(trifluoromethyl)-biphenyl, bis(dicarboxyphenoxy)tetrakis(trifluoromethyl)biphenyl, 2,2-bis[4-(2,3-dicarboxybenzoyloxy)-phenyl]hexafluoropropane, 2,2-bis[4-(3,4-dicarboxybenzoyloxy)-3-bromophenyl]hexafluoropropane, 2,2-bis[4-(3,4-dicarboxybenzoyloxy)-3,5-dimethylphenyl]hexafluoropropane, 2,2-bis[4-(3,4-dicarboxybenzoyloxy)-phenyl]-octafluorobutane, 2,2-bis[(4-(2-trifluoromethyl-3,4-dicarboxybenzoyloxy)phenyl]hexafluoropropane, 1,3-bis[4-(3,4-dicarboxybenzoyloxy)phenyl]hexafluoropropane, 1,5-bis[4-(3,4-dicarboxybenzoyloxy)phenyl]-decafluoropentane, 1,6-bis[4-(3,4-dicarboxybenzoyloxy)phenyl]dodecafluorohexane, 1,7-bis[4-(3,4-dicarbox- ybenzoyloxy)phenyl]tetradecafluoroheptane, 1.5-bis[4-(3,4-dicarboxybenzoyloxy)-3,5-dibromophenyl]-decafluoropentane, 1.5-bis[4-(3,4-dicarboxybenzoyloxy)-3,5-bistrifluoromethylphenyl]decafluoropentane, 1,5- bis[4-(2-trifluoromethyl-3,5-dicarboxybenzoyloxy)phenyl]decafluoropentane, 2.2-bis[4-(3.4-dicarbox- yphenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(2,3-dicarboxyphenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(3,4-dicarboxyphenoxy)-3-bromophenyl]hexafluoropropane, 2.2-bis[4-(3.4-dicarboxyphenoxy ! -3.5-dibromophenyl]hexafluoropropane, 2,2-bis[4-(3,4-dicarboxyphenoxy)-3,5-dimethylphenyl]hexafluoropropane, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]octafluorobutene, 2.2-bis[4-(3,4-dicarboxy-2-trifluoromethylphenoxy)-phenyl]-hexafluoropropane, 1,3-bis[4-(3,4-dicarboxyphenoxy) phenyl]hexafluoropropane. 1.5-bis[4-(3.4-dicar- boxyphenoxy)phenyl]decafluoropentane, 1,6-bis[4-(3,4-dicarboxyphenoxy)phenyl]dodecafluorohexane. 1,7- bis[(4-(3,4-dicarboxyphenoxy)phenyl]tetradecafluoropentane, 1,5-bis[4-(3,4-dicarboxyphenoxy)-3,5-dibromophenyl]decafluoropentane. 1,5-bis[4-(3,4-dicarboxyphenoxy)4,5-bistrffluoromethylphenyl]-decafluoropentane. and 1,5-bis[4-(3.4-dicarboxy-2-trifluoromethylphenoxy)phenyl]decafluoropentane.

Claim 27

A device according to Claim 20, wherein said carboxylic acid-originated moiety has been derived from two or more species of carboxylic acids.

Claim 28

A device according to Claim 20, wherein said diamine-originated moiety has been originated from two or more species of diamines.

Claim 29

A device according to Claim 20, wherein said polyimide film has been subjected to a uniaxial aligning treatment.

Claim 30

A device according to Claim 26, wherein said uniaxial aligning treatment is rubbing.

Claim 31

A device according to Claim 26, wherein said polyimide film subjected to a uniaxial aligning treatment is disposed by the medium of an insulating film on an electrode which is in turn disposed on a substrate.

Claim 32

A device according to Claim 28, wherein said polyimide film has a thickness of 50 - 1000 A. and said insulating film has a thickness of 200 - 1000 Â.

Claim 33

A device according to Claim 28, wherein said polyimide film has a thickness of 100 A or less.

Claim 34

A device according to Claim 20, wherein said pair of substrates are disposed to have a spacing small enough to suppress the formation of a helical alignment structure of the chiral smectic liquid crystal.

Claim 35

A device according to Claim 31, wherein said chiral smectic liquid crystal has been cooled from a temperature higher than a range giving smectic A phase to form at least two different stable orientation states.

Claim 36

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates: each substrate being coated with an alignment film comprising a polyimide which has a fluorine-containing substituent in its diamine- originated moiety, each alignment film having been subjected to a uniaxial aligning treatment so that the resultant pair of alignment films have directions of the uniaxial aligning treatment which intersect each other at an intersection angle.

Claim 37

A liquid crystal device, comprising: a pair of substrates and a chiral smectic liquid crystal disposed between the substrates: each substrate being coated with an alignment film comprising a polyimide which has a fluorine-containing substituent in its diamine- originated moiety, each alignment film having been subjected to a uniaxial aligning treatment so that the resultant pair of alignment films have directions of the uniaxial aligning treatment which intersect each other at an intersection angle.

Claim 38

A device according to Claim 33, wherein said fluorine-containing substituent is a fluoroalkyl group.

Claim 39

A device according to Claim 33, wherein said uniaxial aligning treatment is rubbing.

Claim 40

A device according to Claim 33, wherein said polyimide film subjected to a uniaxial aligning treatment is disposed by the medium of an insulating film on an electrode which is in turn disposed on a substrate.

Claim 41

A device according to Claim 36. wherein said polyimide film has a thickness of 50 - 1000 A. and said insulating film has a thickness of 200 1000 A.

Claim 42

A device according to Claim 36, wherein said polyimide film has a thickness of 100 A or less.

Claim 43

A device according to Claim 33, wherein said polyimide film subjected to a uniaxial aligning treatment is disposed by the medium of an insulating film on an electrode which is disposed on each of said pair of substrates. so that the resultant pair of polyimide films have directions of the uniaxial aligning treatment which intersect each other at an intersection angle of 2 - 15 degrees.

Claim 44

A device according to Claim 39, wherein said intersection angle is 3 - 12 degrees.

Claim 45

A device according to Claim 33, wherein said polyimide film subjected to a uniaxial aligning treatment is disposed on each of the pair of substrates and the directions of the uniaxial aligning treatment axes provided to the resultant pair of polyimide films are such that the uniaxial aligning treatment axis provided to the polyimide film disposed on one of the substrates which is closer to a viewing position is disposed to have a counter-clockwise angle of 2 - 15 degrees from the uniaxial aligning treatment axis provided to the polyimide film disposed on the other of the substrates which is farther from the viewing position.

Claim 46

A device according to Claim 41, wherein the counter-clockwise angle is set within the range of 3 -12 degrees.

Claim 47

A device according to Claim 33, wherein said pair of substrates are disposed to have a spacing small enough to suppress the formation of a helical alignment structure of the chiral smectic liquid crystal.

Claim 48

A device according to Claim 43, wherein said chiral smectic liquid crystal has been cooled from a temperature higher than a range giving smectic A phase to form at least two different stable orientation states.