Liquid crystalline medium and liquid crystal display

Patent metadata

Field	Value
Publication number	US-9822307-B2
Application number	US-201514808156-A
Country	US
Kind code	B2
Filing date	Jul 24, 2015
Priority date	May 6, 2010
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

The instant invention relates to liquid crystalline media comprising
a chiral component, component A, consisting of one or more chiral compounds, optionally, a bimesogenic component, component B, consisting of one or more bimesogenic compounds, a liquid crystalline component, component C, consisting of one or more liquid crystalline, respectively mesogenic compounds, and a reactive mesogenic component, component D, comprising, one or more reactive mesogenic compounds,

as defined in claim 1 , to their stabilization by polymerization and to the polymer-stabilised liquid crystal materials, as well as to liquid crystal displays comprising these liquid crystal media, respectively these stabilized materials, especially to USH-displays and in particular to active matrix displays and, last not least, to the processes of preparation of the respective composite systems and of the displays comprising these systems.

First claim

The invention claimed is:

1. Liquid crystal medium, which comprises
a chiral component, component A, consisting of one or more chiral compounds, and comprising one or more chiral compounds which exhibit an absolute value of the HTP of 50 μm −1 or more,
a bimesogenic component, component B, consisting of one or more bimesogenic compounds,
a liquid crystalline component, component C, consisting of one or more liquid crystalline and mesogenic compounds, and
a reactive mesogenic component, component D, comprising, one or more di-reactive mesogenic compounds.

2. Liquid crystal medium according to claim 1 , which further comprises
a polymerisation initiator.

3. Liquid crystal medium according to claim 1 , which comprises
one or more compounds of formula III′

wherein
R 3 is alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy, alkenyl, alkenyloxy, alkoxyalkyl, fluorinated alkenyl or fluorinated alkenyloxy,

Y 31 and Y 32 are independently of each other H or F,
Y 3 is CN or NCS, and
i is 0 or 1.

4. A liquid crystal device comprising a liquid crystal medium according to claim 1 .

5. Process of stabilizing a liquid crystal medium according to claim 1 , which comprises polymerizing the liquid crystal medium.

6. Polymer stabilized liquid crystal material obtained by polymerizing a liquid crystal medium according to claim 1 .

7. Liquid crystal display, which comprises a liquid crystal medium according to claim 1 .

8. Liquid crystal display according to claim 7 , wherein the liquid crystal medium is aligned in the uniformly standing helix mode.

9. Liquid crystal display according to claim 7 , which is addressable by an active matrix.

10. A process for the preparation of a composite comprising a liquid crystalline material and a polymeric material by polymerisation of a di-reactive mesogenic compound of component D according to claim 1 , in a liquid crystalline medium according to claim 1 .

11. A process for the preparation of a liquid crystal display comprising polymerizing a polymer precursor in a liquid crystalline medium according to claim 1 , wherein the polymer precursor is a di-reactive mesogenic compound of component D.

12. Liquid crystal medium according to claim 3 , which comprises one or more compounds of formula III′ wherein
R 3 is alkyl or alkoxyalkyl,
Y 31 is F and Y 32 is H, and
Y 3 is CN.

13. Liquid crystal medium according to claim 12 , wherein
R 3 is n-alkyl.

14. Liquid crystal medium according to claim 1 , wherein:
Component A comprises one or more compounds of the formulae I, I′ or I″:

wherein
R 11 ,R 12 and R 13 are each, independently of one another, H, F, Cl, CN, NO 2 , NCS, SCN, OCN, a straight- chain or branched alkyl group with 1 to 25 C atoms which may be unsubstituted, mono- or polysubstituted by halogen or CN, it being also possible for one or more non-adjacent CH 2 groups to be replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—,—OCOO—, —S—CO—, —CO—S—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF— or —C≡C— in such a manner, that oxygen atoms are not linked directly to one another, or, in case they are not linked to an 0 atom;
Y independently has one of the meanings given fore;
SP 11 , SP 12 and SP 13 are each, independently of one another, a divalent spacer group comprising 1 to 40 C atoms, it being also possible for one or more CH 2 groups in the spacer groups to be replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—,—OCOO—, —S—CO—, —CO—S—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF—, —CF 2 — or —C≡C— in such a manner, that oxygen atoms are not linked directly to one another;
SP 14 and SP 15 are each, independently of one another, a divalent spacer group comprising 1 to 40 C atoms;
X 11 , X 12 and X 13 are each, independently of one another, —O—, —S—, —CO—, —COO—, —OCO—, —OCOO—, —CO—NH—, —NH—CO—, —CH 2 CH 2 —, —OCH 2 —, —CH 2 O—, —SCH 2 —, —CH 2 S—, —CF═CF—, —CH═CH—, —OCO—CH═CH—, —C≡C— or a single bond;
k, l, n, m, p and q are each, independently of one another, 0 or 1;
m+n+q is 1, 2 or 3;
MG 11 , MG 12 and MG 13 are each, independently of one another, a mesogenic group;
CH* 11 is a chiral, bivalent group;
CH* 12 is a chiral, bivalent group; and
CH* 13 is a chiral, trivalent group;

Component B comprises one or more compounds of formula II:

wherein
R 21 and, R 22 are each, independently of one another, F, Cl, CN, NO 2 , NCS, SCN, OCN, a straight-chain or branched alkyl group with 1 to 25 C atoms which may be unsubstituted, mono- or polysubstituted by halogen or CN, it being also possible for one or more non-adjacent CH 2 groups to be replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—, —OCOO—, —S—CO—, —CO—S—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF— or —C≡C— in such a manner, that in the whole molecule oxygen atoms are not linked directly to one another, or, in case they are not linked to an O atom, one or both of them may be H;
MG 21 and MG 22 are each, independently of one another, a mesogenic group,
SP 2 is a divalent spacer group comprising 1 to 40 C atoms, it being also possible for one or more CH 2 groups in the spacer groups to be replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—,—OCOO—, —S—CO—, —CO—S—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF—, —CF 2 — or —C≡C— in such a manner, that oxygen atoms are not linked directly to one another;
i and j are, independently of each other, 0 or 1;

Component C comprises one or more compounds of one of formulae III-VI:

wherein
R 3 is H, F, alkyl, alkoxy, fluorinated alkyl or fluorinated alkoxy with 1 to 7 C-atoms, or alkenyl, alkenyloxy, alkoxyalkyl or fluorinated alkenyl with 2 to 7 C-atoms;
X 3 CN or NCS;
Z 31 and Z 32 , independently of each other, and in case Z 31 is present twice, also these independently of each other, are —CH 2 —CH 2 —, —CF 2 —CF 2 —, —CF 2 —O—, —O—CF 2 ——CO—O— or a single bond;

 independently of each other, and in case

 is present twice, also these independently of each other, are

K is 0, 1 or 2;

wherein
R 41 and R 42 independently of each other have the meaning given for R 3 under formula III above;

one of

and the other one has, or the other two, independently of each other, have the same meaning, or one of the meanings given for

Assignees

• Merck Patent Gmbh

Inventors

• Lee Seung-Eun
• Lee Sang-Kyu
• Jin Heui-Seok
• Park Won-Hoon
• Skjonnemand Karl
• Wilkes David
• Adlem Kevin
• Saxton Patricia
• Parri Owain Llyr

Classifications

• C09K2019/0448

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

• C09K19/2028

  containing additionally a linking group other than -COO- or -OCO-, e.g. -CH2-CH2-, -CH=CH-, -C=C-; containing at least one additional carbon atom in the chain containing -COO- or -OCO- groups, e.g. -COO-CH*-CH3 · CPC title

• C09K2019/3015

  Cy-Cy-Ph-Cy · CPC title

• C09K19/588

  Heterocyclic compounds · CPC title

• C09K2019/548

  stabilizing the alignment; Polymer stabilized alignment · CPC title