US4421670A
Expired / Lapsed
US
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Liquid crystal dihydrophenanthrene substances
Assignee: Werk fuer Fernsehelektronik im VEB Kombinat Mikroelektronik VEB
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Filing: 1981-09-14
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Granted: 1983-12-20
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Expires: 2001-09-14
Abstract
Abstract This invention relates to new liquid crystal dihydrophenanthrene substances for utilization in electro-optical devices for the modulation of light as well as the representation of numerals, signs and images. It has been found that new liquid-crystal 7-n-alkyl-8, 10-dihydrophenanthrene-2-carboxylic acid esters of the general formula ##STR1## alone, in mixture with each other and/or in mixtures with other liquid crystal or non liquid crystal substances, yield good results when they are used in electro-optical components.
Inventors
- 👤 Hans-Joachim Deutscher
- 👤 Sabine Richter
- 👤 Horst Zaschke
- 👤 Dietrich Demus
- 👤 Ute Boettger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:06
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/32
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
48 words
7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid esters of the general formula ##STR19## wherein R 1 =C n H 2n+1 , ##STR20## R 2 =--C n H 2n+1 , --C n H 2n+1 O, --CN, --Cl, --Br, --CF 3 , --CH 2 --CH 2 --CN--CH═C(CN) 2 with n equal to 1 to 10.
Claim 2
Dependent Claim
48 words
7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid esters of the general formula ##STR19## wherein R 1 =C n H 2n+1 , ##STR20## R 2 =--C n H 2n+1 , --C n H 2n+1 O, --CN, --Cl, --Br, --CF 3 , --CH 2 --CH 2 --CN--CH═C(CN) 2 with n equal to 1 to 10.
Claim 3
Dependent Claim
12 words
A 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR21##
Claim 4
Dependent Claim
24 words
A 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that n=4 and R 1 =OC 7 H 15 , having the formula ##STR22##
Claim 5
Dependent Claim
12 words
A 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR23##
Claim 6
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR24##
Claim 7
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR25##
Claim 8
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR26##
Claim 9
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR27##
Claim 10
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR28##
Claim 11
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR29##
Claim 12
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR30##
Claim 13
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR31##
Claim 14
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR32##
Claim 15
Dependent Claim
12 words
A 4-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester according to claim 1, characterized in that ##STR33##
Claim 16
Dependent Claim
35 words
A nematic liquid crystal composition for modulation of incident and traversing light, and for representation of numerals, signs, and images in electro-optical devices, comprising at least one liquid crystal 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester of claim 1.
Claim 17
Dependent Claim
24 words
The composition of claim 15 wherein said 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester is mixed with at least one other nematic liquid crystal substance of different structure.
Claim 18
Dependent Claim
20 words
The composition of claim 16 wherein said 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester is mixed with at least one other non-liquid crystal substance.
Claim 19
Dependent Claim
123 words
A process for preparing a 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester of claim 1, comprising the steps of (A) catalytically hydrogenating phenanthrene(I) under high pressure, ##STR34## (B) acylating the resultant 8,10-dihydrophenanthrene(II) in the 2-position by a Friedel-Crafts reaction, ##STR35## (C) reducing the resultant 2-n-acyl-8,10-dihydrophenanthrene(III) with hydrazine hydrate, ##STR36## (D) acetylating the resultant 2-n-alkyl-8,10-dihydrophenanthrene(IV) in the 7-position by a Friedel-Crafts reaction in nitrobenzene at a temperature below 0° C., ##STR37## (E) oxidizing the resultant 7-n-alkyl-2-n-acetyl-8,10-dihydrophenanthrene(V) into carboxylic acid, ##STR38## (F) heating the resultant 7-n-alkyl-8,10-dihydrophenanthrene-2carboxylic acid in the presence of thionyl chloride to form the corresponding 7 acyl chloride, ##STR39## and (G) reacting approximately equivalent quantities of the 7-n-alkyl-8,10-dihydrophenanthrene-2-acyl chloride with an hydroxy compound of formula R 1 OH, to form the 7-n-alkyl-8,10-dihydrophenanthrene-2-carboxylic acid ester of claim 1.
Claim 20
Dependent Claim
12 words
An electro-optical device comprising the nematic, liquid crystal composition of claim 15.
References Cited (Backward Citations)
US3655694A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |