Liquid crystal medium and liquid crystal display

Patent metadata

Field	Value
Publication number	US-9475990-B2
Application number	US-201214236741-A
Country	US
Kind code	B2
Filing date	Jul 13, 2012
Priority date	Aug 1, 2011
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

The instant invention relates to mesogenic media comprising one or more compounds selected from the group of compounds of formulae M-I and M-II

wherein the parameters are as specified in the text, preferably to mesogenic media showing a blue phase, preferably stabilized by a polymer, and their use in electro-optical light modulation elements and their respective use in displays, as well as to such devices.

First claim

The invention claimed is:

1. A mesogenic medium exhibiting a blue phase, comprising one or more compounds of formula M-I or M-II

and one or more compounds of formula I

wherein
R 0 * is F, CF 3 or CN,
L 0 is F,
R 0 is alkyl, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
Y 01 and Y 02 are, independently of each other, F, Cl or CN, and alternatively one of them may be H,
R 01 and R 02 are, independently of each other, H or alkyl with 1 to 12 C-atoms
L 1 is H or F, and
R 1 is alkyl, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another.

2. The mesogenic medium according to claim 1 , further comprising one or more compounds of formula II

wherein
R 2 * is F or CF 3 ,
L 21 to L 23 are, independently of each other, H or F,
R 2 is alkyl, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
Y 01 and Y 02 are, independently of each other, F, Cl or CN, and alternatively one of them may be H, and
R 01 and R 02 are, independently of each other, H or alkyl with 1 to 12 C-atoms.

3. The mesogenic medium according to claim 1 , which comprises one or more polymerizable compounds.

4. The mesogenic medium according to claim 1 , further comprising one or more compounds of formula III

wherein
R 2 * is F or CF 3 ,
R 3 is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
Y 01 and Y 02 are, independently of each other, F, Cl or CN, and alternatively one of them may be H, and
R 01 and R 02 are, independently of each other, H or alkyl with 1 to 12 C-atoms.

5. The mesogenic medium according to claim 1 , further comprising one or more compounds of formula IV or V

wherein
R 4 and R 5 are, independently of each other, alkyl, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S— or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
L 5 is H or F,

n and m are, independently of one another, 0 or 1.

6. The mesogenic medium according to claim 1 , which comprises one or more compounds of formula M-I.

7. A mesogenic medium exhibiting a blue phase, comprising one or more compounds of formula M-II

wherein
R 0 * is F, CF 3 or CN,
L 0 is F,
R 0 is alkyl, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
Y 01 and Y 02 are, independently of each other, F, Cl or CN, and alternatively one of them may be H, and
R 01 and R 02 are, independently of each other, H or alkyl with 1 to 12 C-atoms.

8. A method for stabilizing the mesogenic medium according to claim 3 , comprising polymerizing the polymerizable compounds in said medium.

9. The mesogenic medium according to claim 3 , which has been stabilized by the polymerization of the polymerizable compounds in said medium.

10. A light modulation element, comprising a medium according to claim 1 .

11. An electro-optical display, comprising a medium according to claim 1 .

12. The mesogenic medium according to claim 6 ,
wherein
R 0 * is CF 3 or CN.

13. The mesogenic medium according to claim 1 , further comprising one or more compounds of formula P
P a -(Sp a ) s1 -(A 1 -Z 1 ) n1 -A 2 -Q-A 3 -(Z 4 -A 4 ) n2 -(Sp b ) s2 -P b   P

wherein
P a , P b each, independently of one another, are a polymerisable group,
Sp a , Sp b each, independently of one another, denote a spacer group,
s1, s2 each, independently of one another, denote 0 or 1,
n1, n2 each, independently of one another, denote 0 or 1, preferably 0,
Q 1 denotes —CF 2 O—, —OCF 2 —, —CH 2 O—, —OCH 2 —, —(CO)O—, —O(CO)—, —(CH 2 ) 4 —, —CH 2 CH 2 —, —CF 2 —CF 2 —, —CF 2 —CH 2 —, —CH 2 —CF 2 —, —CH═CH—, —CF═CF—, —CF═CH—, —(CH 2 ) 3 O—, —O(CH 2 ) 3 —, —CH═CF—, —C≡C—, —O—, —CH 2 —, —(CH 2 ) 3 —, —CF 2 —,
Z 1 , Z 4 denote a single bond, —CF 2 O—, —OCF 2 —, —CH 2 O—, —OCH 2 —, —(CO)O—, —O(CO)—, —(CH 2 ) 4 —, —CH 2 CH 2 —, —CF 2 —CF 2 —, —CF 2 —CH 2 —, —CH 2 —CF 2 —, —CH═CH—, —CF═CF—, —CF═CH—, —(CH 2 ) 3 O—, —O(CH 2 ) 3 , —CH═CF—, —C≡C—, —O—, —CH 2 —, —(CH 2 ) 3 —, —CF 2 —, where Z 1 and Q 1 or Z 2 and Q 1 do not simultaneously denote a group selected from —CF 2 O— and —OCF 2 —,
A 1 , A 2 , A 3 , A 4 each, independently of one another, denote
a) trans-1,4-cyclohexylene, 1,4-cyclohexenylene or 1,4′-bicyclohexylene, in which one or more non-adjacent CH 2 groups are replaced by —O— and/or —S— and in which one or more H atoms are optionally replaced by F,
b) 1,4-phenylene or 1,3-phenylene, in which one or two CH groups are optionally replaced by N and in which one or more H atoms are optionally replaced by L,
c) tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, tetrahydrofuran-2,5-diyl, cyclobutane-1,3-diyl, piperidine-1,4-diyl, thiophene-2,5-diyl or selenophene-2,5-diyl, each of which is optionally mono- or polysubstituted by L, or
d) a saturated, partially unsaturated or fully unsaturated, and optionally substituted, polycyclic radicals having 5 to 20 cyclic C atoms,

Assignees

• Wittek Michael
• Tanaka Norihiko
• Fischer Mila
• Bremer Matthias
• Taugerbeck Andreas
• Merck Patent Gmbh

Inventors

• Wittek Michael
• Tanaka Norihiko
• Fischer Mila
• Bremer Matthias
• Taugerbeck Andreas

Classifications

• C09K2019/0466

  the linking chain being a -CF2O- chain · CPC title

• C09K2019/0448

  the end chain group being a polymerizable end group, e.g. -Sp-P or acrylate · CPC title

• C09K19/3469

  Pyrimidine with a specific end-group other than alkyl, alkoxy or -C*- · CPC title

• C09K2019/123

  Ph-Ph-Ph · CPC title

• C09K19/0275 Primary

  Blue phase · CPC title