IL41423A

IL41423A - Modified nematic phases

Info

Publication number: IL41423A
Application number: IL41423A
Authority: IL
Original assignee: Merck Patent Gmbh
Priority date: 1972-02-26
Filing date: 1973-01-30
Publication date: 1976-01-30
Also published as: FR2173301B1; DE2209127A1; DD106762A5; CH585256A5; NL7301300A; FR2173301A1; BE795849A; SU469264A3; ATA164173A; IL41423A0; IT979477B; GB1376115A; JPS4899085A; AT326191B

Claims

1. A What we claim is : -1. A modified nematic phase comprising a known nematic phase containing 0.001 to 2% by weight of at least one carboxylic acid of the general formula:- H00C-(HC=CH) and/or at least one salt thereof, in which Y is -R^ or -A-^^-R2, A is -CH = CH-, -XC = CH-.,. -HC = CX-, -C Ξ C-, -N = N-, -N = N-, -N = N-, -0 - CO-, -CO - 0-, -CH = N-, o o -N an alkyl or alkoxy radical containing 6 to 8 carbon atoms or an acyloxy radical containing 4 to 18 carbon atoms, Rg is an alkyl, alkoxy or acyloxy radical containing up to 18 carbon atoms, X is a halogen atom and n is 0 or , with the proviso that ^ = g when n is 1.

2. A modified phase according to claim 1, wherein the 1 acid and/or salt is present in an amount of 0.01 to 0.25% by weight. \

3. A modified phase according to claim 1 or 2, wherein the halogen atom X is a chlorine atom.

4. » A modified phase according to any of the preceding claims, wherein the radical A of the carboxylic acid is . also present in at least one of the molecules forming the nematic phase.

5. A modif ed phase according to any of the preceding claims, wherein the salt used is a quaternary ammonium-and/or phosphonium salt.

6. A modified phase according to any of the preceding A claims, wherein the' hematic phase comprises at least one isomeric pair and/or at least one eutectic mixture of compounds of,' the; general formula :- in which A has the same meaning as in claim 1 and and 'Rg, which may he the same or different, are alkyl, alkoxy or acyloxy radicals containing up to 18 carbon atoms.

7. A modified phase according to claim 6, wherein the substituents and Rg contain up to 8 carbon atoms.

8. ; A modified phase according to any of the preceding,;, claims, wherein the nematic phase comprises a eutectic mixture of -(n-butyl)- ' -methoxy-azoxybenzene and -et-hyl- -methoxy-azoxybenzene.

9. A modified phase according to any of the preceding claims, wherein the nematic phase comprises a eutectic mixture of j2, -di~(n-butyl)-p_'-azoxybenzene and the isomer pair _-(n-butyl)- ' -methoxy-azoxybenzene .

10. A modified phase according to any of the preceding claims, wherein the carboxylic acid is ,-(£-methoxy-phenylazoxy)-benzoic acid and/or _-(_-ethoxy-phenylazoxy)-benzoic acid.

11. Modified nematic phases according to claim 1 , substantially as hereinbefore described and exemplified.

12... A process for the modification of a nematic phase,, wherein a known nematic phase is mixed with 0.001 to 2% by weight of at least one carboxylic acid of the general formula given in claim 1 and/or with at least one salt thereof.

13. A process according to claim 12, wherein there is used 0.01 to 0.25% by weight of at least one ' carboxylic acid of the general formula given in claim 1 and/or at least one salt thereof.

14. 12+. A process according to claim 12 or 13,. wherein the radical A of the carboxylic acid is also present in at least one of the molecules forming the nematic phase.

15. process according to any of claims 12 to 1 , wherein the salt used is a quaternary ammonium and/or phosphonium salt.

16. A process.t.aceording .to any of claims 12 to 15, wherein the nematic- hase to be modified comprises at least one isomeric 'pair and/or at least one eutectic mixture of compounds of the general formula given in claim 6.

17. A process according to any of claims 12 to 16, wherein the nematic phase to be modified comprises a eutectic mixture . of - (n-butyl)-i|.' -methoxy-azoxybenzene and i^-ethyl-V -methoxy-azoxybenzene .

18. A process according to any of claims 12 to 17, wherein the; nematic phase comprises a eutectic mixture . of £,p_' -di-(n-butyl)-£T-azoxybenzene and the isomer pair £- (n-butyl)-£' -methoxy-azoxybenzene .

19.- A process according to any of claims 12 to. 18, wherein the carboxylic acid used is p_-(_-methoxy-phenylazoxy) -benzo c · acid · and/o £- (_-etho.xy-phenylazox )-benzoic acid.

20. A process according to claim 2 for the modification of nematic phases , substantially as hereinbefore described and exemplified.

21. Modified nematic phases, whenever prepared by the process according to any of claims 12 to 20.

22. Indicator devices, whenever comprising a modified nematic phase according to any of claims 1 to 11 and 21. P. O. Box 33116 , Tel-Avi Attorneys for Applicant