LIQUID-CRYSTALLINE MIXTURES

Abstract

The present application relates to mixtures which have liquid-crystalline properties. The application furthermore relates to the use of the mixtures in devices which regulate the transmission of light through an area element.

Claims

1. Mixture comprising one or more compounds which conform to a formula (1) or a formula (2), ##STR00108## where the following applies to the variables occurring: A.sup.11, A.sup.12, A.sup.21, A.sup.22, A.sup.23, A.sup.24 are selected from ##STR00109## Z.sup.11, Z.sup.21, Z.sup.22, Z.sup.23 are selected from a single bond, (CO)O, O(CO), CF.sub.2O, OCF.sub.2, OCH.sub.2, CH.sub.2O and CH.sub.2CH.sub.2; R.sup.11, R.sup.12, R.sup.21, R.sup.22 are selected on each occurrence, identically or differently, from H, F, Cl, CN, NCS, alkyl groups having 1 to 10 C atoms, alkoxy groups having 1 to 10 C atoms, thioalkoxy groups having 1 to 10 C atoms, alkenyl groups having 2 to 10 C atoms and alkenyloxy groups having 2 to 10 C atoms, where one or more H atoms in the alkyl, alkoxy, thioalkoxy, alkenyl and alkenyloxy groups may be replaced by F, Cl or CN; T is selected from CN, F, N.sub.3, NCS, NO.sub.2, CCR.sup.3, alkyl groups having 1 to 10 C atoms and alkoxy groups having 1 to 10 C atoms, where one or more H atoms in the alkyl and alkoxy groups may be replaced by F, Cl or CN; R.sup.3 is selected from H, CN, alkyl groups having 1 to 10 C atoms, where one or more C atoms in the alkyl groups may be replaced by F, Cl or CN, and CCR.sup.4; R.sup.4 is selected from H, CN, and alkyl groups having 1 to 10 C atoms, where one or more C atoms in the alkyl groups may be replaced by F, Cl or CN; i is on each occurrence, identically or differently, 0 or 1, where the sum of the indices i in a formula is at least equal to 1; k is on each occurrence, identically or differently, 0 or 1, where the sum of the indices k in a formula is at least equal to 1; p is equal to 0 or 1; and one or more compounds of the formula (3) ##STR00110## where the following applies to the variables occurring: A31 is selected on each occurrence, identically or differently, from ##STR00111## R.sup.31 and R.sup.32 are selected on each occurrence, identically or differently, from H, F, Cl, CN, NCS, alkyl groups having 1 to 10 C atoms, alkoxy groups having 1 to 10 C atoms, thioalkoxy groups having 1 to 10 C atoms, alkenyl groups having 2 to 10 C atoms and alkenyloxy groups having 2 to 10 C atoms, where one or more H atoms in the alkyl, alkoxy, thioalkoxy, alkenyl and alkenyloxy groups may be replaced by F, Cl or CN; Z.sup.31 is selected on each occurrence, identically or differently, from a single bond, (CO)O, O(CO), CF.sub.2O, OCF.sub.2, OCH.sub.2, CH.sub.2O and CH.sub.2CH.sub.2; m is equal to 0, 1, 2 or 3; where the sum of the proportions of the compounds of the formula (1), the compounds of the formula (2) and the compounds of the formula (3) in the mixture is at least 58%, and where one or both of the following conditions a) and b) are satisfied: a) the mixture comprises one or more compounds V which contain four or more rings, b) the mixture comprises a proportion of at least 25% of compounds of the formula (2).

2. Mixture according to claim 1, characterised in that the compound of the formula (1) conforms to the formula (1-1) ##STR00112## where T, R.sup.11 and R.sup.12 are defined as in claim 1.

3. Mixture according to claim 1, characterised in that the compound of the formula (2) conforms to the formula (2-1), (2-2), (2-3) or (2-4) ##STR00113## where R.sup.21, R.sup.22, A.sup.21, A.sup.22, A.sup.23, A.sup.24 and T are defined as in claim 1.

4. Mixture according to claim 1, characterised in that the compound of the formula (2) conforms to a formula (2-1-1) ##STR00114## where R.sup.21, R.sup.22 and T are defined as claim 1.

5. Mixture according to claim 4, characterised in that it has a proportion of at least 25% of compounds of the formula (2-1-1).

6. Mixture according to claim 1, characterised in that the compound V conforms to a formula (V-1) ##STR00115## where Z.sup.V1 is selected from (CO)O and CH.sub.2O, and where AV1 is selected on each occurrence, identically or differently, from ##STR00116## and where R.sup.V1 and R.sup.V2 are selected on each occurrence, identically or differently, from H, F, Cl, CN, NCS, alkyl groups having 1 to 10 C atoms, alkoxy groups having 1 to 10 C atoms, thioalkoxy groups having 1 to 10 C atoms, alkenyl groups having 2 to 10 C atoms and alkenyloxy groups having 2 to 10 C atoms, where one or more H atoms in the alkyl, alkoxy, thioalkoxy, alkenyl and alkenyloxy groups may be replaced by F, Cl or CN.

7. Mixture according to claim 1, characterised in that the compound of the formula (3) conforms to one of the formulae (3-A), (3-B) and (3-C) ##STR00117## where R.sup.31, R.sup.32, Z.sup.31 and A.sup.31 are defined as in claim 1.

8. Mixture according to claim 1, characterised in that A.sup.31 in formulae (3) is selected on each occurrence, identically or differently, from ##STR00118##

9. Mixture according to claim 1, characterised in that it comprises one or more compounds of the formula (3-1) ##STR00119## where R.sup.31, R.sup.32, Z.sup.31 and m are defined as in claim 1, and where A.sup.31-1 is selected on each occurrence, identically or differently, from ##STR00120##

10. Mixture according to claim 1, characterised in that it comprises both one or more compounds of the formula (1) and also one or more compounds of the formula (2).

11. Mixture according to claim 1, characterised in that compounds of the formula (1) are present in the mixture in a proportion of at least 25%.

12. Mixture according to claim 1, characterised in that compounds of the formula (2) are present in the mixture in a proportion of at least 25%.

13. Mixture according to claim 1, characterised in that the sum formed from the proportions of the compounds of the formula (1), formula (2) and formula (3) is greater than 95%.

14. Mixture according to claim 1, characterised in that it comprises a proportion of less than 60% of compounds which contain one or more benzene rings.

15. Mixture according to claim 1, characterised in that it comprises one or more dyes.

16. Mixture according to claim 1, characterised in that it comprises one or more dyes which are selected from azo compounds, anthraquinones, benzothiadiazoles, diketopyrrolopyrroles and rylenes.

17. Optical switching device comprising a layer which comprises a mixture according to claim 1.

18. Switchable window comprising a layer which comprises a mixture according to claim 1.

Description

WORKING EXAMPLES

[0141] Structures of liquid-crystalline compounds are reproduced by abbreviations (acronyms) below. These abbreviations are explicitly presented and explained in WO 2012/052100 (pp. 63-89), so reference is made to the said published application for an explanation of the abbreviations in the present application.

[0142] In addition, the following acronyms are used:

##STR00106##

[0143] All physical properties are determined in accordance with Merck Liquid Crystals, Physical Properties of Liquid Crystals, Status November 1997, Merck KGaA, Germany, and apply for a temperature of 20 C.

A) Liquid-Crystalline Mixtures Used

[0144] The following mixtures according to the invention are prepared:

TABLE-US-00003 M-1 Cl.p. 115.5 n (20 C., 589.3 nm) 0.0475 n.sub.e (20 C., 589.3 nm) 1.5252 n.sub.o (20 C., 589.3 nm) 1.4777 (20 C., 1 kHz) 5.6 _parallel (20 C., 1 kHz) 3.4 _perpendicular (20 C., 1 kHz) 9.0 Composition Compound % CCN-47 14 CCN-55 14 CCN-33 2 CCZC-3-3 3 CCZC-3-5 3 CC-3-O1 11 CC-5-O1 5 CC-5-O2 4 CCY-3-O2 3 CCY-5-O2 3 BCN-35 12 BCN-55 14 BCN-53 12

TABLE-US-00004 M-2 Cl.p. 114.6 n (20 C., 589.3 nm) 0.0454 n.sub.e (20 C., 589.3 nm) 1.5230 n.sub.o (20 C., 589.3 nm) 1.4776 (20 C., 1 kHz) 5.2 _parallel (20 C., 1 kHz) 3.33 _perpendicular (20 C., 1 kHz) 8.49 Composition Compound % CCN-47 14 CCN-55 14 CCN-33 6 CCZC-3-3 3 CCZC-3-5 3 CCZC-4-3 3 CCZC-4-5 3 CC-3-O1 11 CC-5-O1 4 CC-5-O2 4 BCN-35 10 BCN-55 12 BCN-53 10 CCZPC-3-3 3

TABLE-US-00005 M-3 Cl.p. 113.0 n (20 C., 589.3 nm) 0.0499 n.sub.e (20 C., 589.3 nm) 1.5299 n.sub.o (20 C., 589.3 nm) 1.4800 (20 C., 1 kHz) 5.1 _parallel (20 C., 1 kHz) 3.26 _perpendicular (20 C., 1 kHz) 8.37 Composition Compound % CCN-47 14 CCN-55 14 CCN-33 5 CCZC-3-3 2 CCZC-3-5 3 CC-2-3 6 CC-3-4 5 CP-3-O2 11 BCN-35 11 BCN-55 14 BCN-53 11 CCZCC-2-3 2 CCZCC-3-2 2

TABLE-US-00006 M-4 Cl.p. 114.0 n (20 C., 589.3 nm) 0.0518 n.sub.e (20 C., 589.3 nm) 1.5317 n.sub.o (20 C., 589.3 nm) 1.4799 (20 C., 1 kHz) 4.9 _parallel (20 C., 1 kHz) 3.32 _perpendicular (20 C., 1 kHz) 8.17 Composition Compound % CCN-47 14 CCN-55 14 CCN-33 5 CCZC-3-3 2 CCZC-3-5 3 CCZC-4-3 2 CC-3-O1 6 CC-5-O1 5 CP-3-O2 11 BCN-35 9 BCN-55 12 BCN-53 9 CCZCC-2-3 2 CCZCC-3-2 2 CCZPC-3-3 2 CCZPC-3-4 2

TABLE-US-00007 M-5 Cl.p. 111.0 n (20 C., 589.3 nm) 0.0450 n.sub.e (20 C., 589.3 nm) 1.5224 n.sub.o (20 C., 589.3 nm) 1.4774 (20 C., 1 kHz) 4.9 _parallel (20 C., 1 kHz) 3.24 _perpendicular (20 C., 1 kHz) 8.10 Composition Compound % CCN-47 14 CCN-55 14 CCN-33 5 CCZC-3-3 3 CCZC-3-5 3 CCZC-4-3 3 CCZC-4-5 3 CC-2-3 6 CC-3-4 5 CC-3-O1 11 BCN-35 10 BCN-55 12 BCN-53 10 CCZPC-3-3 2

TABLE-US-00008 M-6 Cl.p. 116.0 n (20 C., 589.3 nm) 0.0448 n.sub.e (20 C., 589.3 nm) 1.5240 n.sub.o (20 C., 589.3 nm) 1.4792 (20 C., 1 kHz) 5.4 _parallel (20 C., 1 kHz) 3.42 _perpendicular (20 C., 1 kHz) 8.80 Composition Compound % CCN-47 15 CCN-55 15 CCN-33 11 CC-3-O1 11 CC-5-O1 5 CC-5-O2 2 CCZCC-2-3 2 CCZCC-3-2 2 CCZCC-4-2 2 BCN-35 10 BCN-55 10 BCN-53 8 CCZPC-3-3 3 CCZPC-3-4 2 CCZPC-3-5 2

TABLE-US-00009 M-7 Cl.p. 113.0 n (20 C., 589.3 nm) 0.0443 n.sub.e (20 C., 589.3 nm) 1.5227 n.sub.o (20 C., 589.3 nm) 1.4784 (20 C., 1 kHz) 5.4 _parallel (20 C., 1 kHz) 3.41 .sub.| (20 C., 1 kHz) 8.82 Composition Compound % CCN-47 15 CCN-55 15 CCN-33 11 CCZC-3-3 3 CCZC-3-5 3 CCZC-4-3 3 CCZC-4-5 3 CC-3-O1 11 CC-5-O1 2 BCN-35 14 BCN-55 14 CCOCC-3-2 2 CCOCC-2-3 2 CCOCC-4-2 2

TABLE-US-00010 M-8 Cl.p. 117.5 n.sub.e (20 C., 589.3 nm) 1.5222 n.sub.o (20 C., 589.3 nm) 1.4779 n (20 C., 589.3 nm) 0.0443 _parallel (20 C., 1 kHz) 3.39 _perpendicular (20 C., 1 kHz) 8.94 (20 C., 1 kHz) 5.5 Composition Compound % CCN-47 15 CCN-55 15 CCN-33 8 CC-3-O1 11 CC-5-O1 5 CCZC-3-3 3 CCZC-3-5 3 CCZCC-2-3 2 CCZCC-3-2 2 CCZCC-4-2 2 CCZCC-4-3 2 BCN-35 16 BCN-55 16

TABLE-US-00011 M-9 Cl.p. ( C.) 111 n (20 C., 589.3 nm) 0.068 (20 C., 1 kHz) 5.1 Composition Compound % CCN-47 15 CCN-55 15 CY-3-O4 11 CCY-3-O2 8 CCY-3-O3 9 CCY-5-O2 10 CCY-3-1 4 CCZC-3-3 3 CCZC-3-5 3 CCZC-4-3 3 CC-3-O1 11 CCZCC-2-3 2 CCZCC-3-2 2 CCZCC-4-2 2 CCZCC-4-3 2

TABLE-US-00012 M-10 Cl.p. 127 n (20 C., 589.3 nm) 0.060 (20 C., 1 kHz) 4.6 Composition Compound % CY-3-O4 12 CCY-3-O2 8 CCY-5-O2 9 CCZC-3-3 3 CCZC-3-5 2 CC-3-O1 11 CC-5-O1 10 CC-5-O2 5 BCN-35 16 BCN-55 16 CCZPC-3-3 2 CCZCC-2-3 2 CCZCC-3-2 2 CCZCC-4-2 2

TABLE-US-00013 M-11 Cl.p. ( C.) 115 n (20 C., 589.3 nm) 0.053 (20 C., 1 kHz) 3.9 Composition Compound % CY-3-O4 12 CCY-3-O2 8 CCZC-3-3 3 CCZC-3-5 2 CCZC-4-3 2 CCZC-4-5 2 CC-3-O1 9 CC-3-O3 9 CC-5-O1 10 CC-5-O2 5 BCN-35 16 BCN-55 16 CCZPC-3-3 2 CCZCC-2-3 2 CCZCC-3-2 2

TABLE-US-00014 M-12 Cl.p. ( C.) 117.5 n (20 C., 589.3 nm) 0.0443 (20 C., 1 kHz) 5.5 Composition Compound % CCN-47 15 CCN-55 15 CCN-33 8 CCZC-3-3 3 CCZC-3-5 3 CC-3-O1 11 CC-5-O1 5 CCZCC-2-3 2 CCZCC-3-2 2 CCZCC-4-2 2 CCZCC-4-3 2 BCN-35 16 BCN-55 16

TABLE-US-00015 M-13 Cl.p. ( C.) 108 n (20 C., 589.3 nm) 0.061 (20 C., 1 kHz) 5.6 Composition Compound % CCN-47 15 CCN-55 15 CCY-3-O3 3 CCY-3-O2 8 CCY-5-O2 10 CY-3-O4 9 CCZC-3-3 3 CCZC-3-5 3 CC-3-O1 11 CC-5-O1 4 BCN-55 15 CCZPC-3-3 2 CCZPC-3-4 2

TABLE-US-00016 M-14 Cl.p. ( C.) 108 n (20 C., 589.3 nm) 0.060 (20 C., 1 kHz) 5.4 Composition Compound % CCN-47 15 CCN-55 15 CCY-3-O2 8 CY-3-O2 12 CCZC-3-3 3 CC-3-O1 11 BCN-35 16 BCN-55 16 CCZPC-3-3 2 CCZPC-3-4 2

TABLE-US-00017 M-15 Cl.p. ( C.) 107 n (20 C., 589.3 nm) 0.054 (20 C., 1 kHz) 6.5 Composition Compound % CCN-47 15 CCN-55 15 CCY-3-O2 8 CCY-5-O2 10 CY-3-O2 12 CCZC-3-3 3 CC-3-O1 11 BCN-35 11 BCN-55 11 CCZPC-3-3 2 CCZPC-3-4 2

TABLE-US-00018 M-16 Cl.p. ( C.) 112 n (20 C., 589.3 nm) 0.051 (20 C., 1 kHz) 5.4 Composition Compound % CCN-47 15 CCN-55 15 CCY-3-O2 8 CCZC-3-3 3 CC-3-O1 11 CC-5-O1 9 CC-5-O2 3 BCN-35 16 BCN-55 16 CCZPC-3-3 2 CCZPC-3-4 2

B) Dyes Used

[0145] ##STR00107##

C) Measurement of the Shelf Life of the Mixtures

[0146] The mixtures prepared have a long shelf life at low temperatures. The shelf life is determined by storing the samples at the temperature in question and determining the time period during which no visible crystallisation or decomposition occurs. The following data are measured for the shelf life:

TABLE-US-00019 M-2 Shelf life (bulk, 20 C.) >214 days Shelf life (bulk, 30 C.) >214 days Shelf life (bulk, 40 C.) 53 days M-3 Shelf life (bulk, 20 C.) >214 days Shelf life (bulk, 30 C.) >214 days Shelf life (bulk, 40 C.) 96 days M-4 Shelf life (bulk, 20 C.) >214 days Shelf life (bulk, 30 C.) >214 days Shelf life (bulk, 40 C.) 120 days M-5 Shelf life (bulk, 20 C.) >209 days Shelf life (bulk, 30 C.) >209 days Shelf life (bulk, 40 C.) 59 days M-6 Shelf life (bulk, 20 C.) >209 days Shelf life (bulk, 30 C.) >209 days Shelf life (bulk, 40 C.) >209 days M-8 Shelf life (bulk, 20 C.) >204 days Shelf life (bulk, 30 C.) >204 days Shelf life (bulk, 40 C.) >204 days

D) Use Examples

[0147] Switching devices containing the mixtures according to the invention are produced. These have the following layer sequence:

[0148] a) glass layer comprising polished 1.1 mm soda-lime glass from Corning

[0149] b) ITO layer, 200 {dot over (A)}ngstrm

[0150] c) alignment layer 01 comprising polyimide JALS-2096-R1 from JSR, rubbed

[0151] d) switchable layer comprising liquid-crystalline medium (composition and thickness indicated below in the case of the corresponding examples)

[0152] e) alignment layer O2, structure as in c); rubbed at the angle indicated below to the rubbing direction of layer c)

[0153] f) as for b)

[0154] g) as for a)

[0155] The ITO layers are provided correspondingly with contacts in order to be electrically switchable.

Example 1

[0156] 0.33% of D1, 0.50% of B2 and 0.60% of D3 are added to 98.57% of mixture M-12. 0.524% of chiral dopant S-811 is added to 99.476% of this mixture. The pitch is 23.1 m.

[0157] The mixture is introduced into the device described above with a layer thickness of 15.4 m. The tilt angle of the cell is 88.5 relative to the substrate plane. The twist (angle between the rubbing directions of O1 and O2) is 240.

[0158] The following values for the light transmittance are obtained for the device at an operating temperature of 20 C.:

TABLE-US-00020 .sub.V dark state .sub.V bright state .sub.V [%] [%] [%] 22.9 72.7 49.8

[0159] The light transmittance .sub.V is determined in accordance with European Standard EN410, equation (1) (Determination of luminous and solar characteristics of glazing) from the measured spectral transmittances taking into account the relative spectral distribution of the standard illuminant and the spectral brightness sensitivity of the standard observer.

[0160] The example shows a large range of the light transmittance (.sub.V) of 49.8%. Only few visible streaks from the glass waviness and only few particle defects are evident.

Example 2

[0161] 0.6% of D1, 0.85% of B2 and 1.2% of D3 are added to 97.35% of mixture M-2. 0.522% of chiral dopant S-811 is added to 99.478% of this mixture. The pitch is 22.4 m.

[0162] The mixture is introduced into the device described above with a layer thickness of 15 m. The tilt angle of the cell is 88 relative to the substrate plane. The twist (angle between the rubbing directions of O1 and O2) is 240.

[0163] The following values for the light transmittance are obtained for the device at operating temperatures between 20 C. and 100 C.:

TABLE-US-00021 .sub.V bright state .sub.V dark state .sub.V Temperature [%] [%] [%] 20 C. 48.0 10.0 38.0 40 C. 45.2 9.6 35.6 60 C. 41.7 10.7 31.0 80 C. 37.2 11.0 26.2 100 C. 30.5 9.7 20.8

[0164] This example shows that the functioning ability of the devices is retained with the mixtures according to the invention within a broad temperature range, in particular at temperatures of 100 C., in particular substantially constant values for the light transmission in the bright and dark states are retained.