Method for reducing white flicker
A method for reducing white flicker by bringing together into a composition one or more compounds of formula G with one or more compounds of formula B and/or C to form a liquid crystal (LC) medium having negative dielectric anisotropy, wherein the reduction of white flicker is achieved compared to an otherwise identical composition, but which does not include either (i) a compound of formula G or (ii) a compound of formula B and/or C.
1 . A method for reducing white flicker induced by affecting a flexoelectric effect of a liquid crystal (LC) medium,
wherein said LC medium has negative dielectric anisotropy,
said method comprising adding to said LC medium one or more compounds of formula G and one or more compounds of formula B and/or C, and applying a voltage to the resultant LC medium containing the one or more compounds of formula G and the one or more compounds of formula B and/or C, leading to an effect that reduces white flicker,
wherein the reduction of white flicker is achieved in said resultant LC medium containing the one or more compounds of formula G and the one or more compounds of formula B and/or C compared to the LC medium to which a compound of formula G has not been added:
in which the individual radicals, on each occurrence identically or differently, and each, independently of one another, have the following meanings:
denotes
R 0 , R 1 , R 2 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen,
L 1 , L 2 denote F or Cl,
X 0 denotes F, Cl, CN, SF 5 , SCN, NCS, or a halogenated alkyl radical or a halogenated alkoxy radical having 1 to 6 C atoms, or a halogenated alkenyl radical or a halogenated alkenyloxy radical having 2 to 6 C atoms,
Y 1 denotes O, S or CH 2 O, and
Z 0 denotes a single bond, —C 2 H 4 —, —CH 2 O—, —CF 2 O—, or —CH═CH—;
and wherein said resultant LC medium is not the following medium
CCP-3-1
3.0%
CCP-V-1
2.5%
CLY-3-O2
8.0%
CLY-4-O2
8.0%
CLY-5-O2
7.0%
CPY-3-O2
6.5%
B(S)-2O-O4
4.0%
B(S)-2O-O5
6.0%
B(S)-2O-O6
3.0%
CC-3-V1
8.0%
CC-4-V1
20.0%
CC-3-V
6.0%
Y-4O-O4
10.0%
CCG-V-F
8.0%
Σ
100.0%.
2 . A method for reducing white flicker induced by affecting a flexoelectric effect of a liquid crystal (LC) medium,
wherein said LC medium has negative dielectric anisotropy,
wherein said LC medium contains one or more compounds of formula B and/or C,
said method comprising adding to said LC medium one or more compounds of formula G, and applying a voltage to the resultant LC medium containing the one or more compounds of formula G, leading to an effect that reduces white flicker,
wherein the reduction of white flicker is achieved in said resultant LC medium containing the one or more compounds of formula G compared to said LC medium to which a compound of formula G has not been added:
in which the individual radicals, on each occurrence identically or differently, and each, independently of one another, have the following meanings:
denotes
R 0 , R 1 , R 2 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen,
L 1 , L 2 denote F or Cl,
X 0 denotes F, Cl, CN, SF 5 , SCN, NCS, or a halogenated alkyl radical or a halogenated alkoxy radical having 1 to 6 C atoms, or a halogenated alkenyl radical or a halogenated alkenyloxy radical having 2 to 6 C atoms,
Y 1 denotes O, S or CH 2 O, and
Z 0 denotes a single bond, —C 2 H 4 —, —CH 2 O—, —CF 2 O—, or —CH═CH—;
and wherein said resultant LC medium is not the following medium
CCP-3-1
3.0%
CCP-V-1
2.5%
CLY-3-O2
8.0%
CLY-4-O2
8.0%
CLY-5-O2
7.0%
CPY-3-O2
6.5%
B(S)-2O-O4
4.0%
B(S)-2O-O5
6.0%
B(S)-2O-O6
3.0%
CC-3-V1
8.0%
CC-4-V1
20.0%
CC-3-V
6.0%
Y-4O-O4
10.0%
CCG-V-F
8.0%
Σ
100.0%.
3 . The method according to claim 1 , wherein the one or more compounds of formula B are selected from the following formulae
wherein
R 1 and R 2 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen.
4 . The method according to claim 1 , wherein the one or more compounds of formula C are selected from the following formulae
wherein
R 1 and R 2 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen.
5 . The method according to claim 1 , wherein the one or more compounds of formula G are selected from the following formulae
wherein
R 0 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen.
6 . The method according to claim 1 , wherein the LC medium additionally comprises one or more compounds selected from formulae CY and PY:
in which the individual radicals have the following meanings:
a denotes 1 or 2,
b denotes 0 or 1,
denotes
R 1 and R 2 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH 2 groups may be replaced by —O—, —CH═CH—, —CO—, —O—CO— or —CO—O— in such a way that O atoms are not linked directly to one another,
Z x and Z y each, independently of one another, denotes —CH═CH—, —CH 2 O—, —OCH 2 —, —CF 2 O—, —OCF 2 —, —O—, —CH 2 —, —CH 2 CH 2 — or a single bond,
L 1-4 each, independently of one another, denote F, Cl, OCF 3 , CF 3 , CH 3 , CH 2 F, or CHF 2 , and
L 5 denotes H or CH 3 .
7 . The method according to claim 1 , wherein the LC medium additionally comprises one or more compounds selected from formula ZK and one or more compounds selected from formula DK
in which the individual radicals on each occurrence, identically or differently, have the following meanings:
denotes
denotes
denotes
and
R 3 and R 4 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH 2 groups may be replaced by —O—, —CH═CH—, —CO—, —O—CO— or —CO—O— in such a way that O atoms are not linked directly to one another,
Z y denotes —CH 2 CH 2 —, —CH═CH—, —CF 2 O—, —OCF 2 —, —CH 2 O—, —OCH 2 —, —COO—, —OCO—, —C 2 F 4 —, —CF═CF— or a single bond,
R 5 and R 6 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH 2 groups may be replaced by —O—, —CH═CH—, —CO—, —OCO— or —COO— in such a way that O atoms are not linked directly to one another, and
e denotes 1 or 2.
8 . The method according to claim 1 , wherein the LC medium additionally comprises one or more compounds selected from the following formulae
in which
alkyl and alkyl* each, independently of one another, denote a straight-chain alkyl radical having 1-6 C atoms, and
alkenyl and alkenyl* each, independently of one another, denote a straight-chain alkenyl radical having 2-6° C. atoms.
9 . The method according to claim 1 , wherein the LC medium additionally comprises s one or more compounds of the following formula
in which the individual radicals, on each occurrence identically or differently, and each, independently of one another, have the following meaning
R 1 , R 2 each, independently of one another, denote alkyl having 1 to 12 C atoms, in which one or two non-adjacent CH 2 groups may be replaced by —O—, —CH═CH—, —CO—, —O—CO— or —CO—O— in such a way that O atoms are not linked directly to one another, and
L T1 -L T6 denote H, F or Cl, with at least one of L T1 to L T6 being F or Cl.
10 . The method according to claim 1 , wherein the LC medium comprises one or more compounds of formula C1
wherein
R 1 and R 2 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen.
11 . The method according to claim 1 , wherein the LC medium comprises one or more compounds of formula B
in which the individual radicals, on each occurrence identically or differently, and each, independently of one another, have the following meanings:
R 1 , R 2 denote a straight chain alkyl or alkoxy radical having 1 to 15 C atoms or a branched alkyl or alkoxy radical having 3 to 15 C atoms, in which one or more CH 2 groups may each be replaced, independently of one another, by
—C≡C—, —CF 2 O—, —OCF 2 —, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and in which one or more H atoms may be replaced by halogen,
L 1 , L 2 denote F or Cl, and
Y 1 denotes O, S or CH 2 O.
12 . The method according to claim 1 , wherein the resultant LC medium contains 2 to 20% by weight the one or more compounds of formula G.
13 . The method according to claim 1 , wherein the resultant LC medium contains 4 to 10% by weight the one or more compounds of formula G.
14 . The method according to claim 1 , wherein the resultant LC medium contains 2 to 20% by weight the one or more compounds of formula B.
15 . The method according to claim 1 , wherein the resultant LC medium contains 7 to 14% by weight the one or more compounds of formula B.
16 . The method according to claim 1 , wherein the resultant LC medium contains 2 to 20% by weight the one or more compounds of formula C.
17 . The method according to claim 1 , wherein the resultant LC medium contains 8 to 12% by weight the one or more compounds of formula C.
18 . The method according to claim 1 , wherein the resultant LC medium contains 4 to 10% by weight the one or more compounds of formula G and 7 to 14% by weight the one or more compounds of formula B and 8 to 12% by weight the one or more compounds of formula C.