Compounds for the homeotropic alignment of liquid-crystalline media

Patent metadata

Field	Value
Publication number	US-10538704-B2
Application number	US-201715817893-A
Country	US
Kind code	B2
Filing date	Nov 20, 2017
Priority date	Nov 21, 2016
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

Disclosed are liquid-crystalline media (LC media) comprising a low-molecular-weight component and a polymerisable component. The polymerisable component contains self-aligning, polymerisable meso-gens (polymerisable self-alignment additives) which effect homeotropic (vertical) alignment of the LC media at a surface or the cell walls of a liquid-crystal display (LC display). Disclosed are also LC displays having homeotropic alignment of the LC medium without alignment layers. Further disclosed are the structures for polymerisable self-alignment additives.

First claim

The invention claimed is:

1. A compound of formula IB-1, IB-2, IB-3, IB-4, IC-3 or IC-4

in which
R 2 denotes a straight-chain or branched alkyl, alkenyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which optionally one or more H atoms are replaced by F or Cl, or denotes F, Cl, Br, I, —CN, —NO 2 , —NCO, —NCS, —OCN, —SCN,) —C(═O)N(R 0 ) 2 , —C(═O)R 0 , or optionally substituted aryl or cycloalkyl having 3 to 20 C atoms,
P denotes a polymerisable group,
Sp denotes a spacer group or a single bond,
R a denotes an anchor group of the following formula

p denotes 1 or 2,
o denotes 0 or 1 for formulae IB-1, IB-2, IB-3 and IB-4, and denotes 0 for formulae IC-3 and IC-4,
X 1 each, independently of one another, denotes H, alkyl, fluoroalkyl, —OH, —SH, —NH 2 , —NHR 11 , —NR 11 2 , NHC(O)—R 11 , —OR 11 , —C(O)OH or —CHO,
where at least one group X 1 denotes —OH, —SH, —NH 2 , —NHR 11 , —C(O)OH or —CHO,

R 11 denotes alkyl having 1 to 12 C atoms,
Sp a , Sp c each, in each case, independently of one another, denotes a spacer group or a single bond,
Sp b denotes a tri- or tetravalent group,
R 1 denotes H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH 2 groups are optionally replaced by —O—, —S—, —CH═CH—, —C≡C—, —CO—, —CO—O—, —O—CO— or —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another and in which one or more H atoms are optionally replaced by F or Cl,
or denotes a group -Sp-P, and

R 0 each, in each case, independently of one another, denotes alkyl having 1 to 12 C atoms.

2. The compound according to claim 1 , wherein R 2 denotes F, Cl, CH 3 , ethyl, propyl, cyclopropyl or isopropyl.

3. The compound according to claim 1 , wherein for formulae IB-1, IB-2, IB-3 and IB-4 the group R a contains one or two OH groups.

4. The compound according to claim 1 , wherein for formulae IB-1, IB-2, IB-3 and IB-4 the group R a denotes a group of one of the following formulae

in which
p denotes 1 or 2,
X 1 each, independently of one another, denotes H, alkyl, fluoroalkyl, —OH, —SH, —NH 2 , —NHR 11 , —NR 11 2 , NHC(O)—R 11 , —OR 11 , —C(O)OH or —CHO,
where at least one group X 1 denotes —OH, —SH, —NH 2 , —NHR 11 , —C(O)OH or —CHO,

R 11 denotes alkyl having 1 to 12 C atoms,
Sp a , Sp c each, in each case, independently of one another, denotes a spacer group or a single bond, and
Sp b denotes a tri- or tetravalent group.

5. The compound according to claim 1 , wherein for formulae IB-1, IB-2, IB-3 and IB-4 the group R a denotes one of the following formulae

and for formulae IC-3 and IC-4 the group R a denotes one of the following formulae

6. The compound according to claim 1 , in which P is acrylate, methacrylate, fluoroacrylate, chloroacrylate, vinyloxy, oxetane or epoxide.

7. A method for effecting a homeotropic alignment with respect to a surface delimiting an LC medium, comprising providing the compound according to claim 1 as additive for said LC media, where said compound is optionally polymerised after effecting the homeotropic alignment.

8. A LC medium comprising a low-molecular-weight, unpolymerisable, liquid-crystalline component and a polymerisable or polymerised component comprising one or more polymerisable compounds according to claim 1 , where the polymerised component is obtainable by polymerisation of the polymerisable component.

9. A LC medium according to claim 8 , which comprises said one or more polymerisable compounds in a concentration of less than 10% by weight.

10. A LC medium according to claim 9 , further comprising one or more polymerisable compounds of formula M or a (co)polymer comprising one or more compounds of formula M:
P 1 -Sp 1 -A 2 -(Z 1 -A 1 ) n -Sp 2 -P 2   M

in which
P 1 , P 2 each independently denote a polymerisable group,
Sp 1 , Sp 2 each independently denote a spacer group,
A 1 , A 2 each, independently of one another, denotes
a) trans-1,4-cyclohexylene, 1,4-cyclohexenylene or 4,4′-bicyclohexylene, in which one or more non-adjacent CH 2 groups are optionally replaced by —O— and/or —S— and in which one or more H atoms are optionally replaced by a group L, or denotes

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 a group L or -Sp 3 -P,
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 a group L,
d) a saturated, partially unsaturated or fully unsaturated, and optionally substituted, polycyclic radical having 5 to 20 cyclic C atoms, one or more of which is optionally replaced by heteroatoms,

P 3 denotes a polymerisable group,
Sp 3 denotes a spacer group,
n denotes 0, 1, 2 or 3,
Z 1 each, in each case, independently of one another, denotes —CO—O—, —O—CO—, —CH 2 O—, —OCH 2 —, —CF 2 O—, —OCF 2 —, or —(CH 2 ) n2 —,where n2 is 2, 3 or 4, —O—, —CO—, —C(R c R d )—, —CH 2 CF 2 —, —CF 2 CF 2 — or a single bond,
L on each occurrence, identically or differently, denotes F, Cl, CN, SCN, SF 5 or straight-chain or branched, in each case optionally fluorinated, alkyl, alkoxy, alkylcarbonyl, alkoxy-carbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms,
R 0 , R 00 each, independently of one another, denote H, F or straight-chain or branched alkyl having 1 to 12 C atoms, in which one or more H atoms are optionally replaced by F, and
R c and R d each, independently of one another, denote H or alkyl having 1 to 6 C atoms
where one or more of the groups P 1 -Sp 1 —, Sp 2 -P 2 and -Sp 3 -P 3 optionally denote a radical R aa , with the proviso that at least one of the groups P 1 -Sp 1 -, -Sp 2 -P 2 and -Sp 3 -P 3 present does not denote R aa ,
R aa denotes H, F, Cl, CN or straight-chain or branched alkyl having 1 to 25 C atoms, in which one or more non-adjacent CH 2 groups are each optionally replaced, independently of one another, by C(R 0 )═C(R 00 )—, —C≡C—, —S—,—CO—, —CO—O—, —O—CO—, or —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another, and in which one or more H atoms are optionally replaced by F, Cl, CN or P 1 -Sp 1 -, which P 1 -Sp 1 - herein cannot be a further R aa group; where the groups —OH, —NH 2 , —SH, —NHR, —C(O)OH and —CHO are not present in R aa .

11. A LC medium according to claim 9 , further comprising one or more compounds

Assignees

• Merck Patent Gmbh

Inventors

• Archetti Graziano
• Plummer Edward
• Haensel Helmut
• Fortte Rocco
• Uebel Timo

Classifications

• C09K19/04 Primary

  characterised by the chemical structure of the liquid crystal components {, e.g. by a specific unit} · CPC title

• C09K2019/0444

  characterized by a linking chain between rings or ring systems, a bridging chain between extensive mesogenic moieties or an end chain group · CPC title

• C09K19/3003 Primary

  Compounds containing at least two rings in which the different rings are directly linked (covalent bond) · CPC title

• C09K2019/122

  Ph-Ph · CPC title

• C09K19/46

  containing esters · CPC title