US4472292A
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Liquid crystalline dielectric, new dichroitic naphthoquinone dyestuffs and electro-optical indicator element
Assignee: Merck Patent GmbH
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Filing: 1982-07-02
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Granted: 1984-09-18
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Expires: 2002-07-02
Abstract
Abstract A liquid crystalline dielectric useful in electro-optical display elements based on the guest-host effect, comprises a liquid crystalline compound and a pleochroitic dyestuff of the formula ##STR1## wherein X and Y are the same or different and each is hydrogen, chlorine or bromine; R 1 , R 2 , R 3 and R 4 each independently is hydrogen, alkyl or alkoxyalkyl each of up to 8 C-atoms or a cyclic group Z, wherein Z is, ##STR2## and R is alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy or alkanoyloxy each of up to 8 C-atoms, with the proviso that at least one and at most two of R 1 , R 2 , R 3 and R 4 is cyclic group Z; and when two Z groups are present, either R 1 and R 2 or R 3 and R 4 are both a cyclic group Z; and, when R 3 and R 4 are both cyclic groups Z, these are in the 2- and 6- or 3- and 7-positions of the naphthalene structure.
Inventors
- 👤 Gunther Haas
- 👤 Georg Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:04
CPC Classifications
C; C09; C09B; C09B13/00; C09B13/02; C09K; C09K19/00; C09K19/52; C09K19/60
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
100 words
In a liquid crystalline dielectric useful in electro-optical display elements based upon a guest-host liquid crystal cell and comprising a liquid crystalline host material and a compatible pleochroitic dyestuff, the improvement wherein the pleochroitic dyestuff is of the formula ##STR14## wherein R 1 and R 2 each independently is hydrogen, alkyl or alkoxyalkyl each of up to 8 C-atoms or a cyclic group Z, wherein Z is, ##STR15## and R is alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy or alkanoyloxy each up to 8 C-atoms, with the proviso that at least one of R 1 and R 2 is a cyclic group Z.
Claim 2
Dependent Claim
100 words
In a liquid crystalline dielectric useful in electro-optical display elements based upon a guest-host liquid crystal cell and comprising a liquid crystalline host material and a compatible pleochroitic dyestuff, the improvement wherein the pleochroitic dyestuff is of the formula ##STR14## wherein R 1 and R 2 each independently is hydrogen, alkyl or alkoxyalkyl each of up to 8 C-atoms or a cyclic group Z, wherein Z is, ##STR15## and R is alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy or alkanoyloxy each up to 8 C-atoms, with the proviso that at least one of R 1 and R 2 is a cyclic group Z.
Claim 3
Dependent Claim
26 words
A liquid crystalline dielectric of claim 1, wherein the dyestuff is a naphthoquinone derivative of the formula ##STR16## wherein Z is as defined in claim 1.
Claim 4
Dependent Claim
17 words
A liquid crystalline dielectric of claim 1, wherein all alkyl portions in all positions are straight chained.
Claim 5
Dependent Claim
18 words
A liquid crystal dielectric of claim 1, wherein the amount of dyestuff is 0.1 to 15% by weight.
Claim 6
Dependent Claim
28 words
In an electro-optical display element based upon a guest-host liquid crystal cell, an improvement wherein the guest-host liquid crystal cell contains a liquid crystalline dielectric of claim 1.
Claim 7
Dependent Claim
12 words
A liquid crystalline dielectric of claim 1, wherein one Z is ##STR17##
Claim 8
Dependent Claim
12 words
A liquid crystalline dielectric of claim 1, wherein one Z is ##STR18##
Claim 9
Dependent Claim
12 words
A liquid crystalline dielectric of claim 1, wherein one Z is ##STR19##
Claim 10
Dependent Claim
12 words
A liquid crystalline dielectric of claim 1, wherein one Z is ##STR20##
Claim 11
Dependent Claim
94 words
A compound of the formula ##STR21## wherein R 5 and R 6 each is hydrogen or alkyl or alkoxyalkyl each of up to 8 C-atoms; R 3 and R 4 each is a cyclic group Z or one is H and the other is a cyclic group Z; Z is ##STR22## and R is alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy or alkanoyloxy each of up to 8 C-atoms; wherein when R 3 and R 4 are both a cyclic group Z, they are in the 2- and 6- or 3- and 7-positions of the naphthalene structure.
Claim 12
Dependent Claim
94 words
A compound of the formula ##STR21## wherein R 5 and R 6 each is hydrogen or alkyl or alkoxyalkyl each of up to 8 C-atoms; R 3 and R 4 each is a cyclic group Z or one is H and the other is a cyclic group Z; Z is ##STR22## and R is alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy or alkanoyloxy each of up to 8 C-atoms; wherein when R 3 and R 4 are both a cyclic group Z, they are in the 2- and 6- or 3- and 7-positions of the naphthalene structure.
Claim 13
Dependent Claim
10 words
A compound of claim 10, wherein one Z is ##STR23##
Claim 14
Dependent Claim
10 words
A compound of claim 10, wherein one Z is ##STR24##
Claim 15
Dependent Claim
10 words
A compound of claim 10, wherein one Z is ##STR25##
Claim 16
Dependent Claim
10 words
A compound of claim 10, wherein one Z is ##STR26##
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |