Claims
- 1. A chiral ester of the formula (I) ##STR13## wherein X.sup.1 is OH, O--CO--(C.sub.1 to C.sub.12)alkyl or O--MC; and
- X.sup.2, independently of X.sup.1, is O--MC;
- wherein MC has the formula (II)
- R--(A.sup.1 --).sub.n1 (B--).sub.n2 (A.sup.2 --).sub.n3 CO (II)
- wherein
- R is a straight-chain or branched (C.sub.1 -C.sub.12)alkyl, where one or two nonadjacent CH.sub.2 groups may be replaced by O atoms;
- A.sup.1 and A.sup.2, independently of each other, are 1,4-phenylene, pyrimidine-2,5-diyl, 1,4-cyclohexylene or 1,3-dioxane-2,5-diyl;
- B is CO--O, O--CO, CH.sub.2 --CH.sub.2, OCH.sub.2, CH.sub.2 O, CH.dbd.N, N.dbd.CH, N.dbd.N or N(O).dbd.N; and
- n2 is 0 or 1; and n3 is 1 or 2; and n1 is 1 or 2 when n2 is 1, or n1 is 0, 1, or 2 when n2 is 0.
- 2. A chiral ester as claimed in claim 1, wherein in the formula (I)
- X.sup.1 and X.sup.2, independently of each other, are O--MC, and in the formula (II)
- R is a straight-chain (C.sub.4 -C.sub.10)alkyl, where one CH.sub.2 group may be replaced by an O atom;
- A.sup.1 and A.sup.2, independently of each other, are 1-4-phenylene or 1-4-cyclohexylene;
- B is CO--O or O--CO;
- n1 is 1;
- n2 is 0 or 1; and
- n3 is 1 or 2.
- 3. A twistable liquid crystal mixture comprising as a dopant at least one chiral compound of the formula (I) as claimed in claim 1.
- 4. The liquid crystal mixture as claimed in claim 3, wherein the total amount of chiral compounds of the formula (I) is 0.01 to 70% by weight.
- 5. A liquid crystal display element containing a liquid crystal mixture as claimed in claim 3.
Priority Claims (2)
Number |
Date |
Country |
Kind |
3534780 |
Sep 1985 |
DEX |
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3604901 |
Feb 1986 |
DEX |
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Parent Case Info
This application is a continuation of application Ser. No. 912,361, filed Sept. 26, 1986, now abandoned.
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4264148 |
Gobl-Wunsch et al. |
Apr 1981 |
|
4454057 |
Kaneko et al. |
Jun 1984 |
|
4457828 |
Lewis |
Jul 1984 |
|
4650600 |
Heppke et al. |
Mar 1987 |
|
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Country |
0138006 |
Apr 1985 |
EPX |
2827471 |
Jan 1980 |
DEX |
3333677 |
Apr 1985 |
DEX |
1603075 |
Nov 1981 |
GBX |
Non-Patent Literature Citations (4)
Entry |
Heppke et al., CA 106:41948r (1987). |
Miyano et al., CA 101:230097 v (1984). |
Byung Wook Jo et al., Makromolekular Chemie Rapid Comm., vol. 3, pp. 23-27 (1982). |
Gottarelli et al., Journal of Organic Chemistry, vol. 51, No. 5, pp. 589-592 (1986). |
Continuations (1)
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Number |
Date |
Country |
Parent |
912361 |
Sep 1986 |
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