Polymerisable mesogenic compound, liquid crystal medium and liquid crystal display

Patent metadata

Field	Value
Publication number	US-10138420-B2
Application number	US-201515501520-A
Country	US
Kind code	B2
Filing date	Jul 17, 2015
Priority date	Aug 5, 2014
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

The present invention relates to liquid crystal media comprising polymerizable mesogenic compounds with a bent shape, and to electro-optical displays comprising these media as light modulation media. In particular the electro-optical displays according to the present invention are displays, which are operated at a temperature, at which the liquid crystal modulation media are in an optically isotropic phase, preferably in a blue phase.

First claim

The invention claimed is:

1. A liquid crystal medium comprising
one or more compounds selected from the following formulae

P 1 , P 2 independently of each other denote a polymerisable group,
Sp 1 , Sp 2 independently of each other denote Sp″-O— or —O-Sp″
Sp″ is alkylene having 1 to 20 C atoms, which is optionally mono- or polysubstituted by F, CI, Br, I or CN and in which, in addition, one or more non-adjacent CH 2 groups may each be replaced, independently of one another, by —O—, —S—, —NH—, —N(R 0 )—, —Si(R 00 R 000 )—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, S—CO—, —CO—S—, —N(R 00 )—CO—O—, —O—CO—N(R 00 )—, —N(R 00 )—CO—N(R 00 )—, —CH═CH— or —C≡C— in such a way that O and/or S atoms are not linked directly to one another,
L denotes P 1 -, P 1 —Sp 1 -, F, Cl, Br, I, —CN, —NO 2 , —NCO, —NCS, —OCN, —SCN, —C(═O)N(R x ) 2 , —C(═O)Y 1 , —C(═O)R x , —N(R x ) 2 , optionally substituted silyl, optionally substituted aryl or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25, particularly preferably 1 to 10, C atoms, in which, in addition, one or more non-adjacent CH 2 groups may each be replaced, independently of one another, by —C(R 00 )═C(R 000 )—, —C≡C—, —N(R 00 )—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F, Cl, CN, P 1 or —Sp 1 -,
R 00 and R 000 each, independently of one another, denote H or alkyl having 1 to 12 C atoms,
Y 1 is halogen,
R x denotes P 1 , P 1 —Sp 1 -, H, halogen, straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH 2 -groups are optionally replaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are optionally replaced by F, Cl, P 1 - or P 1 —Sp 1 -, optionally substituted aryl, aryloxy, heteroaryl or heteroaryloxy having 5 to 20 ring atoms,
r is 1, 2 or 3

and further comprising one or more compounds selected from the group of formulae I-A, I-E, I-N and I-T

wherein
R 0 has the meaning of R 1 ,
R 1 is alkyl, which is straight chain or branched, preferably has 1 to 20 C-atoms, is unsubstituted, mono- or poly-substituted by F, Cl or CN, preferably by F, 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, preferably n-alkyl or n-alkoxy with 1 to 9 C-atoms, preferably with 2 to 5 C-atoms, alkenyl, alkenyloxy or alkoxyalkyl with 2 to 9 C-atoms, preferably with 2 to 5 C-atoms or halogenated alkyl, halogenated alkenyl or halogenated alkoxy with preferably up to 9 C-atoms, preferably mono fluorinated, di-fluorinated or oligofluorinated alkyl, alkenyl or alkoxy with preferably up to 9 C-atoms, most preferably n-alkyl, n-alkoxy, alkenyl, alkenyloxy or alkoxyalkyl with preferably up to 9 C-atoms, and

L 1 to L 03 , L 1 , L 11 and L 12 are independently of one another H or F.

2. The liquid crystal medium according to claim 1 , which further comprises one or more compounds of formula II

wherein
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, preferably by F, 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.

3. The liquid crystal medium according to claim 1 , which further comprises one or more compounds of formula III

wherein R 3 has the meaning given for R 1 in claim 1 .

4. The liquid crystal medium according to claim 1 , which further comprises one or more compounds selected from the group of compounds of formulae IV and V

wherein
R 4 and R 5 are, independently of each other, alkyl, which is straight chain or branched, preferably has 1 to 20 C-atoms, is unsubstituted, mono- or poly-substituted by F, Cl or CN, preferably by F, 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.

5. The liquid crystal medium according to claim 1 , which comprises one or more chiral dopants.

6. The liquid crystal medium according to claim 1 , which is stabilised by the polymerisation of its polymerisable constituents.

7. A method of stabilisation of a liquid crystal medium which comprises subjecting a liquid crystal medium according to claim 1 to polymerisation of its polymerisable constituents.

8. A method which comprises including a liquid crystal medium according to claim 1 in a light modulation element or electro-optical display.

9. A light modulation element or electro-optical display, which comprises a liquid crystal medium according to claim 1 .

10. The light modulation element or electro-optical display of claim 9 , which is operated at a temperature at which the liquid crystal medium is in an optically isotropic phase.

11. The light modulation element or electro-optical display of claim 9 , which is operated at a temperature at which the liquid crystal medium is in a blue phase.

Assignees

• Merck Patent Gmbh

Inventors

• Wittek Michael
• Tanaka Norihiko
• Adlem Kevin
• Bremer Matthias
• Wilkes David
• Wu Ming-Chou

Classifications

• C09K2019/0448

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

• C09K2019/3422

  the heterocyclic ring being a six-membered ring · CPC title

• C09K19/0275 Primary

  Blue phase · CPC title

• C09K19/588

  Heterocyclic compounds · CPC title

• C09K19/46 Primary

  containing esters · CPC title