Liquid-crystal display

• US 8,313,669 B2
• Filed: 07/31/2008
• Issued: 11/20/2012
• Est. Priority Date: 08/30/2007
• Status: Active Grant

• Current Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Original Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Inventors: Bernatz, Georg, Taugerbeck, Andreas
• Primary Examiner(s): Visconti, Geraldina
• Application Number:
  US12/675,453
• Publication Number:
  US 20110101269A1
• Time in Patent Office: 1,573 Days
• Field of Search: None
• US Class Current: 252/299.01
• CPC Class Codes: C09K 19/12 at least two benzene rings directly linked, e.g. biphenyls
• CPC Class Codes: C09K 19/3001 Cyclohexane rings
• CPC Class Codes: C09K 19/3098 Unsaturated non-aromatic rings, e.g. cyclohexene rings
• CPC Class Codes: C09K 19/32 containing condensed ring systems, i.e. fused, bridged or spiro ring systems
• CPC Class Codes: C09K 19/322 Compounds containing a naphthalene ring or a completely or partially hydrogenated naphthalene ring
• CPC Class Codes: C09K 19/3483 the heterocyclic ring being a non-aromatic ring
• CPC Class Codes: C09K 19/42 Mixtures of liquid crystal compounds covered by two or more of the preceding groups C09K19/06 - C09K19/40
• CPC Class Codes: C09K 2019/0448 the end chain group being a polymerizable end group, e.g. -Sp-P or acrylate
• CPC Class Codes: C09K 2019/548 stabilizing the alignment; Polymer stabilized alignment
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: G02F 1/133711 by organic films, e.g. polymeric films
• CPC Class Codes: G02F 1/13775 Polymer-stabilized liquid crystal layers

Abstract

The present invention relates to a liquid-crystal (LC) display of the PS (polymer stabilized) or PSA (polymer sustained alignment) type, and to polymerizable compounds and LC media for use in PS (polymer stabilized) and PSA displays.

Claims

1. A LC medium comprising

a polymerisable component A) comprising one or more polymerisable compounds, and

a liquid-crystalline component B) comprising one or more low-molecular-weight compounds,

wherein component A) comprises one or more polymerisable compounds of formula I

R^a-(A¹-Z¹)_m1-(A²-Z²)_m2-(A³)_m3-R^b 

 

I

in which the individual radicals have the following meanings;

R^a and R^b each, independently of one another, denote P-Sp-, H, halogen, SF₅, NO₂, a carbon group or hydrocarbon group, where at least one of the radicals R^a and R^b denotes P-Sp-,

P on each occurrence, identically or differently, denotes a polymerisable group,

Sp on each occurrence, identically or differently, denotes a spacer group or a single bond,

A¹ and A³ each, independently of one another, denote 1,3-phenylene, naphthalene-1,3-diyl, naphthalene-1,6-diyl, naphthalene-2,5-diyl or naphthalene-2,7-diyl, where, in addition, one or more CH groups in these radicals may be replaced by N, cyclohexane-1,3-diyl, in which, in addition, one or more non-adjacent CH₂ groups may be replaced by O and/or S, 1,3-cyclohexenylene, piperidine-2,4-diyl, piperidine-2,6-diyl, decahydronaphthalene-2,7-diyl, 1,2,3,4-tetrahydronaphthalene-2,7-diyl or indane-2,4-diyl, where all these radicals may be unsubstituted or mono- or polysubstituted by L, and where, in the case where m1=m3=1, one of the radicals A¹ and A³ may also have one of the meanings indicated for A²,

A² on each occurrence, identically or differently, denotes 1,4-phenylene, naphthalene-1,4-diyl or naphthalene-2,6-diyl, where, in addition, one or more CH groups in these radicals may be replaced by N, cyclohexane-1,4-diyl, in which, in addition, one or more non-adjacent CH₂ groups may be replaced by O and/or S, 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-2,5-diyl, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetra-hydronaphthalene-2,6-diyl, indane-2,5-diyl, thiophene-2,5-diyl, fluorene-2,7-diyl or octahydro-4,7-methanoindane-2,5-diyl, where all these radicals may be unsubstituted or mono- or polysubstituted by L, or can have one of the meanings indicated for A¹,

L denotes P-Sp-, H, OH, halogen, SF₅, NO₂, a carbon group or hydrocarbon group,

Z^1,2 each, independently of one another and on each occurrence identically or differently, denote —

O—

, —

S—

, —

CO—

, —

CO—

O—

, —

OCO—

, —

O—

CO—

O—

, —

OCH₂—

, —

CH₂O—

, —

SCH₂—

, —

CH₂S—

, —

CF₂O—

, —

OCF₂—

, —

CF₂S—

, —

SCF₂—

, —

(CH₂)_n1—

, —

CF₂CH₂—

, —

CH₂CF₂—

, —

(CF₂)_n1—

, —

CH═

CH—

, —

CF═

CF—

, —

C≡

C—

, —

CH═

CH—

COO—

, —

OCO—

CH═

CH—

, CR⁰R⁰⁰ or a single bond,

R⁰ and R⁰⁰ each, independently of one another, denote H or alkyl having 1 to 12 C atoms,

m1 and m3 each, independently of one another, denote 0 or 1, where m1+m3>

0,

m2 denotes 0, 1, 2 or 3,

n1 denotes 1, 2, 3 or 4.

2. A LC medium according to claim 1, wherein A^1-3, Z^1-2, P, Sp, m1, m2, m3 and n1 have the meanings indicated in claim 1, and

L denotes P-Sp-, OH, CH₂OH, F, Cl, Br, I, —

CN, —

NO₂, —

NCO, —

NCS, —

OCN, —

SCN, —

C(═

O)N(R^x)₂, —

C(═

O)Y¹, —

C(═

O)R^x, —

N(R^x)₂, optionally substituted silyl, optionally substituted aryl having 6 to 20 C atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which, in addition, one or more H atoms may be replaced by F, Cl or P-Sp-,

Y¹ denotes halogen,

R^x denotes P-Sp-, H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH₂ groups may be replaced by —

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 or P-Sp-, an optionally substituted aryl or aryloxy group having 6 to 40 C atoms or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms,

R denotes P-Sp-, H, L as defined above, or straight-chain or branched alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH₂ groups may each be replaced, independently of one another, by —

C(R^x)═

C(R^x)—

, —

C≡

C—

, —

N(R^x)—

, —

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, Br, I, CN or P-Sp-, where at least one of the radicals R^a and R^b is P-Sp-.

3. A LC medium according to claim 1, wherein the polymerisable compounds are selected from the following sub-formulae:

4. A LC medium according to claim 1, wherein the LC medium comprises one or more compounds of the following formulae:

5. A LC medium according to claim 1, wherein the LC medium comprises one or more compounds of the following formula:

6. A LC medium according to claim 1, in which component B) comprises one or more compounds selected from formulae CY, PY and ZK

7. A LC medium according to claim 1, wherein:

the group P is selected from CH₂═

CW¹—

COO—

, CH₂═

CW¹—

CO—

,

8. A LC medium according to claim 1, wherein:

the group P is selected from CH₂═

CH—

COO—

, CH₂═

C(CH₃)—

COO—

, CH₂═

CH—

, CH₂═

CH—

O—

, (CH₂═

CH)₂CH—

OCO—

, (CH₂═

CH)₂CH—

O—

,

9. A LC medium according to claim 4, wherein Z^x denotes a single bond.

10. Process for the preparation of an LC medium according to claim 6 by mixing one or more component B) low-molecular-weight liquid-crystalline compounds with one or more component A) polymerisable compounds, and optionally with further liquid-crystalline compounds and/or additives.

11. A LC display, which is a PS (polymer stabilised) or PSA (polymer sustained alignment) display, which comprises an LC medium as defined in claim 1.

12. A LC display according to claim 11, which is a PSA-VA, PSA-OCB, PS-IPS, PS-FFS or PS-TN display.

13. A LC display according to claim 11, wherein the PS or PSA LC display contains:

an LC cell consisting of two substrates, where at least one substrate is transparent to light and at least one substrate has an electrode layer; and

a layer of an LC medium comprising a polymerised component and a low-molecular-weight component located between the substrates,

where the polymerised component is obtainable by polymerisation of one or more polymerisable compounds between the substrates of the LC cell in the LC medium with application of an electrical voltage.

14. A compound of the formula I

R^a-(A¹-Z¹)_m1-(A²-Z²)_m2-(A³)_m3-R^b 

 

I

in which

R^a and R^b each, independently of one another, denote P-Sp-, H, halogen, SF₅, NO₂, a carbon group or hydrocarbon group, where at least one of the radicals R^a and R^b denotes P-Sp-,

P on each occurrence, identically or differently, denotes a polymerisable group,

Sp on each occurrence, identically or differently, denotes a spacer group or a single bond,

A¹ and A³ each, independently of one another, denote 1,3-phenylene, naphthalene-1,3-diyl, naphthalene-1,6-diyl, naphthalene-2,5-diyl or naphthalene-2,7-diyl, where, in addition, one or more CH groups in these radicals may be replaced by N, cyclohexane-1,3-diyl, in which, in addition, one or more non-adjacent CH₂ groups may be replaced by O and/or S, 1,3-cyclohexenylene, piperidine-2,4-diyl, piperidine-2,6-diyl, decahydronaphthalene-2,7-diyl, 1,2,3,4-tetrahydronaphthalene-2,7-diyl or indane-2,4-diyl, where all these radicals may be unsubstituted or mono- or polysubstituted by L, and where, in the case where m1=m3=1, one of the radicals A¹ and A³ may also have one of the meanings indicated for A²,

A² on each occurrence, identically or differently, denotes 1,4-phenylene, naphthalene-1,4-diyl or naphthalene-2,6-diyl, where, in addition, one or more CH groups in these radicals may be replaced by N, cyclohexane-1,4-diyl, in which, in addition, one or more non-adjacent CH₂ groups may be replaced by O and/or S, 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-2,5-diyl, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetra-hydronaphthalene-2,6-diyl, indane-2,5-diyl, thiophene-2,5-diyl, fluorene-2,7-diyl or octahydro-4,7-methanoindane-2,5-diyl, where all these radicals may be unsubstituted or mono- or polysubstituted by L, or can have one of the meanings indicated for A¹,

L denotes P-Sp-, H, OH, halogen, SF₅, NO₂, a carbon group or hydrocarbon group,

Z^1,2 each, independently of one another and on each occurrence identically or differently, denote —

O—

, —

S—

, —

CO—

, —

CO—

O—

, —

OCO—

, —

O—

CO—

O—

, —

OCH₂—

, —

CH₂O—

, —

SCH₂—

, —

CH₂S—

, —

CF₂O—

, —

OCF₂—

, —

CF₂S—

, SCF₂—

, —

(CH₂)_n1—

, —

CF₂CH₂—

, —

CH₂CF₂—

, —

(CF₂)_n1—

, —

CH═

CH—

, —

CF═

CF—

, —

C≡

C—

, —

CH═

CH—

COO—

, —

OCO—

CH═

CH—

, CR⁰R⁰⁰ or a single bond,

R⁰ and R⁰⁰ each, independently of one another, denote H or alkyl having 1 to 12 C atoms,

m1 and m3 each, independently of one another, denote 0 or 1, where m1+m3>

0

m2 denotes 0, 1, 2 or 3,

n1 denotes 1, 2, 3 or 4.