Liquid-crystalline media having homeotropic alignment

Patent metadata

Field	Value
Publication number	US-9809748-B2
Application number	US-201514643147-A
Country	US
Kind code	B2
Filing date	Mar 10, 2015
Priority date	Mar 10, 2014
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy, comprising a low-molecular-weight component and a polymerizable component. The polymerizable component comprises self-aligning, polymerizable mesogens (polymerizable 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). The invention therefore also encompasses LC displays having homeotropic alignment of the LC medium without alignment layers. The invention discloses novel structures for self-alignment additives which have a certain position of the functional groups.

First claim

The invention claimed is:

1. A liquid-crystal medium comprising a low-molecular-weight, non-polymerizable liquid-crystalline component and a polymerizable or polymerized component comprising one or more polymerizable compounds of formula I, where the polymerized component is obtainable by polymerization of the polymerizable component,
R 1 -[A 3 Z 3 ] m -[A 2 ] k -[Z 2 ] n -A 1 -R a   (I)

in which
A 1 , A 2 , A 3 each, independently of one another, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group, which may also contain fused rings, and which is unsubstituted or mono- or polysubstituted by a group L or -Sp-P,
L in each case, independently of one another, denotes H, F, Cl, Br, I, —CN, —NO 2 , —NCO, —NCS, —OCN, —SCN, —C(═O)N(R 0 ) 2 , —C(═O)R 0 , optionally substituted silyl, optionally substituted aryl or cycloalkyl having 3 to 20 C atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having up to 25 C atoms, in which, in addition, one or more H atoms are each optionally replaced by F or Cl,
P denotes a polymerizable group,
Sp denotes a spacer group or a single bond,
Z 2 in each case, independently of one another, denotes —O—, —S—, —CO—, —CO—O—, —OCO—, —O—CO—O—, —OCH 2 —, —CH 2 O—, —SCH 2 —, —CH 2 S—, —CF 2 O—, —OCF 2 —, —CF 2 S—, —SCF 2 —, —(CH 2 ) n1 —, —CF 2 CH 2 —, —CH 2 CF 2 —, —(CF 2 ) n1 —, —CH═CH—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH—, —(CR 0 R 00 ) n1 —, —CH(-Sp-P)—, —CH 2 CH(-Sp-P)—, or —CH(-Sp-P)CH(-Sp-P)—,
Z 3 in each case, independently of one another, denotes a single bond, —O—, —S—, —CO—, —CO—O—, —OCO—, —O—CO—O—, —OCH 2 —, —CH 2 O—, —SCH 2 —, —CH 2 S—, —CF 2 O—, —OCF 2 —, —CF 2 S—, —SCF 2 —, —(CH 2 ) n1 —, —CF 2 CH 2 —, —CH 2 CF 2 —, —(CF 2 ) n1 —, —CH═CH—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH—, —(CR 0 R 00 ) n1 —, —CH(-Sp-P)—, —CH 2 CH(-Sp-P)—, or —CH(-Sp-P)CH(-Sp-P)—,
n1 denotes 1, 2, 3 or 4,
n denotes 0 or 1,
m denotes 0, 1, 2, 3, 4, 5 or 6,
k denotes 0 or 1,
R 0 in each case, independently of one another, denotes alkyl having 1 to 12 C atoms,
R 00 in each case, independently of one another, denotes H or alkyl having 1 to 12 C atoms,
R 1 , independently of one another, denotes H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH 2 groups are each optionally replaced by —O—, —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, in addition, one or more H atoms are each optionally replaced by F or Cl,
or a group -Sp-P,

R a denotes an anchor group of the formula

p denotes 1 or 2,
q denotes 2 or 3,
B denotes a substituted or unsubstituted ring system or condensed ring system,
Y, independently of one another, denotes —O—, —S—, —C(O)—, —C(O)O—, —OC(O)—, —NR 11 — or a single bond,
o denotes 0 or 1,
X 1 , independently of one another, denotes H, alkyl, fluoroalkyl, OH, NH 2 , NHR 11 , NR 11 2 , OR 11 , C(O)OH, —CHO,
where at least one group X 1 denotes a radical selected from —OH, —NH 2 , NHR 11 , C(O)OH and —CHO,

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

where the compound of formula I contains at least one polymerizable group P within at least one of the groups A 1 , A 2 , A 3 , Z 2 and Z 3 , as are present.

2. The medium according to claim 1 , wherein, in formula I,
A 1 , A 2 , A 3 each, independently of one another, denote 1,4-phenylene, naphthalene-1,4-diyl or naphthalene-2,6-diyl, where, in addition, one or more CH groups in these groups are each optionally replaced by N, cyclohexane-1,4-diyl, in which, in addition, one or more non-adjacent CH 2 groups are each optionally replaced by O or S, 3,3′-bicyclobutylidene, 1,4-cyclohexenylene, bicyclo[1.1.1]pentane-1,3-diyl, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, piperidine-1,4-diyl, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, indane-2,5-diyl or octahydro-4,7-methanoindane-2,5-diyl, perhydrocyclopenta[a]phenanthrene-3,17-diyl,
wherein each of these groups is unsubstituted or mono- or polysubstituted by a group L or -Sp-P.

3. The medium according to claim 1 , wherein the compound of formula I is a compound of formula II,

in which
R 1 , R a , A 1 , A 2 , A 3 , Z 2 , Z 3 , L, Sp, P, k, m and n independently are as defined in claim 1 ,
p1, p2, p3 independently denote 0, 1, 2 or 3, and
r1, r2, r3 independently denote 0, 1, 2 or 3,
where the compound of the formula I1 contains at least one polymerizable group P within at least one of the groups A 1 , A 2 , A 3 , Z 2 and Z 3 , as are present.

4. The medium according to claim 1 , wherein the compound of formula I contains in total at least one polymerizable group -Sp-P on at least one of the groups A 1 , A 2 and A 3 , as are present.

5. The medium according to claim 1 , wherein said one or more polymerizable compounds of formula I are selected from compounds of formulae IA, IB, IC, ID and IE:

in which
R 1 , R a , Z, Z 3 , L, Sp, P and n independently are as defined in claim 1 ,
p1, p2, p3 independently denote 0, 1, 2 or 3, and
r1, r2, r3 independently denote 0, 1, 2 or 3,
where each of the compounds of formulae IA, IB, IC, ID and IE contains at least one polymerizable group P.

6. The medium according to claim 1 , wherein, besides said one or more polymerizable compounds of formula I, the polymerizable or polymerized component of said medium further comprises one or more further polymerizable or further polymerized compounds, where the polymerized component is obtainable by polymerization of the polymerizable component.

7. The medium according to claim 1 , wherein, besides said one or more compounds polymerizable of formula I, said medium further comprises one or more non-polymerizable compounds of formula I′,
R 1 -[A 3 -Z 3 ] m -[A 2 ] k -[Z 2 ]- n -A 1 -R a   I′

in which
m, k, n and the group R a are as defined for formula I,
A 1 , A 2 , A 3 each, independently of one another, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group, which may also contain fused rings, and which is unsubstituted or mono- or polysubstituted by a group L,
Z 2 in each case, independently of one another, denotes —O—, —S—, —CO—, —CO—O—, —OCO—, —O—CO—O—, —OCH 2 —, —CH 2 O—, —SCH 2 —, —CH 2 S—, —CF 2 O—, —OCF 2 —, —CF 2 S—, —SCF 2 —, —(CH 2 ) n1 —, —CF 2 CH 2 —, —CH 2 CF 2 —, —(CF 2 ) n1 —, —CH═CH—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH—, or —(CR 0 R 00 ) n1 —,
Z 3 in each case, independently of one another, denotes a single bond, —O—, —S—, —CO—, —CO—O—, —OCO—, —O—CO—O—, —OCH 2 —, —CH 2 O—, —SCH 2 —, —CH 2 S—, —CF 2 O—, —OCF 2 —, —CF 2 S—, —SCF 2 —, —(CH 2 ) n1 —, —CF 2 CH 2 —, —CH 2 CF 2 —, —(CF 2 ) n1 —, —CH═CH—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH—, or —(CR 0 R 00 ) n1 —,
n1 denotes 1, 2, 3 or 4,
L in each case, independently of one another, denotes H, F, Cl, Br, I, —CN, —NO 2 , —NCO, —NCS, —OCN, —SCN, —C(═O)N(R 0 ) 2 , —C(═O)R 0 , optionally substituted silyl, optionally substituted aryl or cycloalkyl having 3 to 20 C atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxy

Assignees

• Merck Patent Gmbh

Inventors

• Archetti Graziano
• Saito Izumi
• Fortte Rocco
• Kodek Thorsten

Classifications

• C09K2019/0425

  characterized by a specific unit that results in a functional effect · CPC title

• C09K19/14

  linked by a carbon chain · CPC title

• C09K2019/301

  Cy-Cy-Ph · CPC title

• C09K19/04

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

• C09K2019/3027

  Compounds comprising 1,4-cyclohexylene and 2,3-difluoro-1,4-phenylene · CPC title