US5138010A
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Fast switching polysiloxane ferroelectric liquid crystals
Assignee: University of Colorado Foundation Inc
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Filing: 1990-06-25
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Granted: 1992-08-11
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Expires: 2010-06-25
Abstract
Abstract New ferroelectric liquid crystal (FLC) materials comprising linear and cyclic polysiloxanes are described. The FLCs exhibit high polarization and fast switching speeds. The disclosed polysiloxanes are derivitized with mesogenic groups which induce high polarization, specifically chiral nonracemic epoxide mesogens, having phenylbenzoate, reverse phenylbenzoate and biphenyl cores. These epoxy polysiloxanes are chemically stable over extended periods. Further, the epoxides can be crosslinked to produce FLC elastomers and like materials having optoelectronic applications. It was found that in the pure polysiloxanes, the smectic layers align along the rubbing direction of an anisotropic surface on contact with that surface. An unexpected alignment transition is observed as a function of polysiloxane concentration in polysiloxane/LC monomer mixtures with smectic layers orienting along the rubbing direction at high polymer concentrations and, typical of low molecular weight liquid crystals, normal to the rubbing direction at low polymer concentrations. A method for alignment of FLC polysiloxanes is described. The aligned polysiloxane FLCs and FLC mixtures exhibit high contrast electro optic switching.
Inventors
- 👤 Patrick J. Keller
- 👤 David M. Walba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:59
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/355; G02F1/361; G02F1/3615; G02F1/3617; C; C08; C08G; C08G77/00; C08G77/04; C08G77/38; C09; C09K; C09K19/00; C09K19/02; C09K19/0225; C09K19/04; C09K19/40; C09K19/406; C09K19/408
Claims Analysis
Total Claims: 45
Claim 1
Independent Claim
125 words
A polysiloxane having chiral nonracemic mesogenic side chains which polysiloxane has the formula: ##STR27## wherein R is an alkyl group having from 1 to 3 carbon atoms; y is either 0 or 1 and when y=0, m is a number ranging from about 10 to about 100 and when y=1, m is an integer ranging from about 4 to about 10 and wherein M is a chiral nonracemic mesogenic group having the formula: ##STR28## where x is 0 or 1 and X is --OOC-- or --COO--; Ph is a 1,4 substituted phenyl group; n is an integer from about 6 to 12; and R 3 is a straight chain or branched alkyl group having six or less carbon atoms and "*" indicates an asymmetric carbon.
Claim 2
Dependent Claim
125 words
A polysiloxane having chiral nonracemic mesogenic side chains which polysiloxane has the formula: ##STR27## wherein R is an alkyl group having from 1 to 3 carbon atoms; y is either 0 or 1 and when y=0, m is a number ranging from about 10 to about 100 and when y=1, m is an integer ranging from about 4 to about 10 and wherein M is a chiral nonracemic mesogenic group having the formula: ##STR28## where x is 0 or 1 and X is --OOC-- or --COO--; Ph is a 1,4 substituted phenyl group; n is an integer from about 6 to 12; and R 3 is a straight chain or branched alkyl group having six or less carbon atoms and "*" indicates an asymmetric carbon.
Claim 3
Dependent Claim
7 words
The polysiloxane of claim 1 wherein y=0.
Claim 4
Dependent Claim
18 words
The polysiloxane of claim 2 wherein the configuration of the mesogenic group is 2S, 3S or 2R, 3R.
Claim 5
Dependent Claim
9 words
The polysiloxane of claim 3 wherein x=1 and X=COO.
Claim 6
Dependent Claim
9 words
The polysiloxane of claim 4 wherein n is 10.
Claim 7
Dependent Claim
10 words
The polysiloxane of claim 5 wherein R 3 is n-propyl.
Claim 8
Dependent Claim
11 words
The polysiloxane of claim 2 wherein R is CH 3 .
Claim 9
Dependent Claim
7 words
The polysiloxane of claim 1 wherein y=1.
Claim 10
Dependent Claim
17 words
The polysiloxane of claim 8 wherein m is a number ranging from about 25 to about 80.
Claim 11
Dependent Claim
18 words
The polysiloxane of claim 9 wherein the configuration of the mesogenic group is 2S, 3S or 2R, 3R.
Claim 12
Dependent Claim
9 words
The polysiloxane of claim 10 wherein x=1 and X=COO.
Claim 13
Dependent Claim
7 words
The polysiloxane of claim 11 wherein n=10.
Claim 14
Dependent Claim
10 words
The polysiloxane of claim 12 wherein R 3 is n-propyl.
Claim 15
Dependent Claim
169 words
A polysiloxane copolymer having chiral nonracemic side chains which polysiloxane copolymer has the formula: ##STR29## where R is an alkyl group having three carbons or less carbon atoms and R 1 is a side chain group selected from the group consisting of a straight-chain alkyl group having from one to about six carbon atoms and a mesogenic group, different from M, which is optionally a chiral nonracemic mesogenic group; a and b are numbers greater than 0 wherein a+b, the average degree of polarization, ranges from about 10 to about 100, and wherein b/(a+b), which represents the degree of substitution by M, is at least about 0.05 and M is a chiral nonracemic mesogenic group having the formula: ##STR30## wherein x is 0 or 1 and X is --OOC-- or --COO--; Ph is a 1,4 substituted phenyl group; n is an integer from about 6 to 12; R 3 is a straight chain or branched alkyl group having six or less carbon atoms and "*" indicates an asymmetric carbon.
Claim 16
Dependent Claim
169 words
A polysiloxane copolymer having chiral nonracemic side chains which polysiloxane copolymer has the formula: ##STR29## where R is an alkyl group having three carbons or less carbon atoms and R 1 is a side chain group selected from the group consisting of a straight-chain alkyl group having from one to about six carbon atoms and a mesogenic group, different from M, which is optionally a chiral nonracemic mesogenic group; a and b are numbers greater than 0 wherein a+b, the average degree of polarization, ranges from about 10 to about 100, and wherein b/(a+b), which represents the degree of substitution by M, is at least about 0.05 and M is a chiral nonracemic mesogenic group having the formula: ##STR30## wherein x is 0 or 1 and X is --OOC-- or --COO--; Ph is a 1,4 substituted phenyl group; n is an integer from about 6 to 12; R 3 is a straight chain or branched alkyl group having six or less carbon atoms and "*" indicates an asymmetric carbon.
Claim 17
Dependent Claim
12 words
The polysiloxane of claim 14 wherein b/(a+b) is at least about 0.1.
Claim 18
Dependent Claim
14 words
The polysiloxane of claim 14 wherein a+b ranges from about 20 to about 80.
Claim 19
Dependent Claim
12 words
The polysiloxane of claim 14 wherein b/(a+b) is at least about 0.05.
Claim 20
Dependent Claim
12 words
The polysiloxane of claim 15 wherein b/(a+b) is at least about 0.35.
Claim 21
Dependent Claim
11 words
The polysiloxane of claim 14 wherein R is a methyl group.
Claim 22
Dependent Claim
12 words
The polysiloxane of claim 19 wherein R 1 is a methyl group.
Claim 23
Dependent Claim
14 words
The polysiloxane of claim 20 wherein a+b range from about 20 to about 80.
Claim 24
Dependent Claim
12 words
The polysiloxane of claim 21 wherein b/(a+b) is at least about 0.1.
Claim 25
Dependent Claim
12 words
The polysiloxane of claim 21 wherein b/(a+b) is at least about 0.35.
Claim 26
Dependent Claim
9 words
The polysiloxane of claim 23 wherein x=1 and X=COO.
Claim 27
Dependent Claim
7 words
The polysiloxane of claim 24 wherein n=10.
Claim 28
Dependent Claim
9 words
The polysiloxane of claim 25 wherein R 3 =n-propyl.
Claim 29
Dependent Claim
16 words
The polysiloxane of claim 14 wherein R 1 is a mesogenic group that is not M.
Claim 30
Dependent Claim
14 words
The polysiloxane of claim 27 wherein R 1 is a chiral nonracemic mesogenic group.
Claim 31
Dependent Claim
23 words
The polysiloxane of claim 27 wherein x=1 and X=COO and wherein R 1 is a chiral nonracemic mesogenic phenylbenzoate that is not M.
Claim 32
Dependent Claim
11 words
The polysiloxane of claim 29 wherein R 1 is an omega-[4-decyloxy-4'-[(S)-4-methylheptyl]phenylbenzoate]group.
Claim 33
Dependent Claim
10 words
The polysiloxane of claim 14 wherein a+b is about 25.
Claim 34
Dependent Claim
10 words
The polysiloxane of claim 14 wherein a+b is about 80.
Claim 35
Dependent Claim
138 words
An FLC polysiloxane which has the formula: ##STR31## wherein R 1 is a side chain group selected from the group consisting of a straight-chain alkyl group having from one to about six carbon atoms and a mesogenic group, different from M, which is optionally a chiral nonracemic mesogenic group; a and b are numbers greater than 0 wherein a+b, the average degree of polarization, ranges from about 10 to about 100, and wherein b/(a+b), which represents the degree of substitution by M, is at least about 0.05 and M is a chiral nonracemic mesogenic group having the formula: ##STR32## where Ph is a 1,4 substituted phenyl group; n is an integer from about 6 to 12; R 3 is a straight chain or branched alkyl group having six or less carbon atoms and "*" indicates an asymmetric carbon.
Claim 36
Dependent Claim
138 words
An FLC polysiloxane which has the formula: ##STR31## wherein R 1 is a side chain group selected from the group consisting of a straight-chain alkyl group having from one to about six carbon atoms and a mesogenic group, different from M, which is optionally a chiral nonracemic mesogenic group; a and b are numbers greater than 0 wherein a+b, the average degree of polarization, ranges from about 10 to about 100, and wherein b/(a+b), which represents the degree of substitution by M, is at least about 0.05 and M is a chiral nonracemic mesogenic group having the formula: ##STR32## where Ph is a 1,4 substituted phenyl group; n is an integer from about 6 to 12; R 3 is a straight chain or branched alkyl group having six or less carbon atoms and "*" indicates an asymmetric carbon.
Claim 37
Dependent Claim
20 words
The polysiloxane of claim 33 wherein the configuration of the asymmetric carbons in M is 2S, 3S or 2R, 3R.
Claim 38
Dependent Claim
12 words
The polysiloxane of claim 34 wherein R 1 is a methyl group.
Claim 39
Dependent Claim
12 words
The polysiloxane of claim 35 wherein b/(a+b) is at least about 0.1.
Claim 40
Dependent Claim
12 words
The polysiloxane of claim 35 wherein b/(a+b) is at least about 0.35.
Claim 41
Dependent Claim
16 words
The polysiloxane of claim 34 wherein R 1 is a mesogenic group that is not M.
Claim 42
Dependent Claim
18 words
The polysiloxane of claim 38 wherein R 1 is a chiral nonracemic mesogenic group that is not M.
Claim 43
Dependent Claim
17 words
The polysiloxane of claim 38 wherein R 1 is a mesogenic group that is a phenyl benzoate.
Claim 44
Dependent Claim
7 words
The polysiloxane of claim 34 wherein n=10.
Claim 45
Dependent Claim
10 words
The polysiloxane of claim 41 wherein R 3 is n-propyl.
References Cited (Backward Citations)
US4367924A
Cited
US4563059A
Cited
US4763995A
Cited
US4561726A
Cited
US4639089A
Cited
US4638073A
Cited
US4705874A
Cited
EP0228703A2
Cited
EP0258898A2
Cited
EP0296571A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-11 | 1996-02-10 | 1996-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-11 | 2000-02-10 | 2000-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-11 | 2004-02-10 | 2004-08-11 | $7700.00 | Window Closed / Lapsed |