The invention relates to a process for the purification of a liquid-crystal mixture.
Liquid-crystal mixtures are fluid substances having crystal-like direction-dependent physical properties which are used, for example, in liquid-crystal displays. Commercially available liquid-crystal mixtures which can advantageously be employed in displays have various components which are mixed with one another in a pre-specified ratio to one another. The properties and advantages of the liquid-crystal mixture that are necessary for the respective application can be achieved specifically by suitable specification of individual components and mixing proportions.
It has been found that even slight contamination of a liquid-crystal mixture can result in the properties of the liquid-crystal mixture that are necessary or desired for the intended application being impaired and economically viable use of a pre-specified liquid-crystal mixture for a particular application being made more difficult or even impossible.
Various purification processes by means of which a liquid-crystal mixture can be purified have therefore been disclosed in practice. The various purification processes are based on different methods. In industrial production and processing processes, mechanical filter processes or the addition and subsequent separation of a sorbent represent purification processes which are frequently employed.
The purification processes known from practice often have only low efficiency for the purification of liquid-crystal mixtures and are nevertheless comparatively expensive.
It is therefore regarded as an object of the present invention to design a process for the purification of a liquid-crystal mixture in such a way that the most efficient purification possible of the liquid-crystal mixture can be carried out as inexpensively and reliably as possible.
This object is achieved in accordance with the invention by a purification process in which the liquid-crystal mixture is passed through a first electrodialysis cell, a concentrate solution is passed through a second electrodialysis cell which is adjacent to the first electrodialysis cell and is separated by an ion-exchanger membrane, and, with the aid of an anode/cathode arrangement arranged outside the electrodialysis cells, an electric field transverse to a direction of passage of the liquid-crystal mixture through the first electrodialysis cell is generated so that ionised constituents of the liquid-crystal mixture are discharged from the first electrodialysis cell and are removed from the liquid-crystal mixture. The process according to the invention consequently essentially corresponds to the performance of electrodialysis on the liquid-crystal mixture. It has been found that many impurities relevant in practice can be separated and removed from the liquid-crystal mixture using electrodialysis. Ionised impurities can be removed reliably and with high effectiveness from the liquid-crystal mixture by suitable pre-specification of the concentrate solution and the ion-exchanger membrane delimiting the first electrodialysis cell.
The process according to the invention can be carried out in continuous operation and enables continuous sampling and control of the purification process, so that, depending on the respective liquid-crystal mixture, the contamination thereof and a target degree of purity of the liquid-crystal mixture to be purified, a suitable process duration can be determined and the purification already achieved can be monitored and if necessary regulated while the purification process is being carried out.
According to an advantageous embodiment of the inventive idea, it is provided that the liquid-crystal mixture is passed through the first electrodialysis cell a number of times. It is likewise possible for the liquid-crystal mixture to be passed successively through a plurality of electrodialysis cells having an arrangement, comparable to the first electrodialysis cell, of an ion-exchanger membrane and an adjacent second electrodialysis cell and a comparable electric field. In both cases, it is thereby possible to achieve the situation where a rate of passage of the liquid-crystal mixture and a total purification duration or a total residence time of the liquid-crystal mixture in the first electrodialysis cell or in a comparable electrodialysis cell arrangement can be pre-specified independently of one another. Thus, for example, it is possible, in the case of an impurity which can be removed highly efficiently, for the process duration to be adapted and kept short. If, by contrast, it is observed that the impurity in the liquid-crystal mixture can only be separated and removed from the liquid-crystal mixture comparatively slowly, the purification process can be carried out for a sufficiently long time in order to achieve and reliably guarantee a pre-specified purification effect. Sampling at time intervals or continuously enables the purification effect that has already been achieved to be determined and controlled. Accordingly, the purification process according to the invention also enables regulated purification of a liquid-crystal mixture, so that it can be ensured that a target or necessarily pre-specified degree of purity is also achieved with the purification according to the invention.
According to an embodiment of the inventive idea, it is provided that the liquid-crystal mixture is passed through the first electrodialysis cell over a period of more than one hour, preferably more than 4 hours. If the liquid-crystal mixture is passed successively through a plurality of comparable electrodialysis cells, it may likewise be provided that the total residence time of the liquid-crystal mixture in these electrodialysis cells is more than one hour and preferably more than four hours. It has been found that the specific resistance, which can be regarded as an expedient criterion for the purity of the liquid-crystal mixture, can be increased by more than a factor of 20, depending on the process duration over a period of about 4 hours to 8 hours.
It has proven advantageous for the concentrate solution used to be deionised water. In addition to comparatively effective charge transport in deionised water, the concentration gradient favours osmosis through the ion-exchanger membrane, which results in an additional purifying effect.
However, it is likewise possible and possibly advantageous, depending on the composition of the liquid-crystal mixture, for the concentrate solution used also to be other suitable solutions, such as, for example, transformer oil, dodecane or another organic solvent.
Investigations have shown that a large potential difference and consequently a large electric field transverse to a flow direction of the liquid-crystal mixture through the first electrodialysis cell is particularly advantageous for an effective purification effect. According to an embodiment of the inventive idea, it is therefore provided that the ion-exchanger membrane used is a membrane having a breakdown voltage of greater than 10 volts, preferably greater than 80 volts and particularly preferably 400 volts or more, and an electric potential difference which effects the greatest possible drop in voltage at the ion-exchanger membrane, but which is below the breakdown voltage, is pre-specified with the aid of the anode/cathode arrangement. The breakdown voltage denotes the voltage from which the membrane no longer reliably acts as insulator and current flow through the membrane could impair the electrodialysis. A drop in voltage between 10 and 1000 volts within the first electrodialysis cell is regarded as suitable for carrying out the purification process. The drop in voltage in the first electrodialysis cell should preferably be in a range between 80 volts and 120 volts, which has proven particularly advantageous for the purification process.
In order to prevent water or other mixture components being destroyed at the electrodes, it is, in accordance with an advantageous embodiment of the inventive idea, provided that the anode and cathode are flushed with transformer oil while the process is being carried out. The accessible active surfaces of the anode and cathode can be flushed with the transformer oil continuously or at time intervals. The electrode material used for the anode and for the cathode can preferably be stainless steel, but also graphite, mixed oxides or other suitable electrode materials.
In order to prevent residues of the purified liquid-crystal mixture remaining adhering and being retained in the first electrodialysis cell after a purification operation, it is provided that if possible all surfaces coming into contact with the liquid-crystal mixture to be purified are made, for example, from perfluoroalkoxy polymers (PFA) or are coated therewith. It is likewise possible for the components which come into contact with product, such as, for example, the electrodialysis cell, but also tubes, ion-exchanger membranes or spacer elements in an electrodialysis cell to be made from an inert polymer, such as, for example, polytetrafluoroethylene (PTFE). The components which come into contact with product are advantageously cleaned with organic solvents, such as, for example, acetone or toluene, before beginning a new purification process.
In order to prevent undesired pressure variations in the first electrodialysis cell while the purification process is being carried out, which may favour or cause leakage between adjacent electrodialysis cells, low-pulsation pumps are used to convey the liquid-crystal mixture and the concentrate solution. It has been found that, for example, the use of gear pumps enables the liquid-crystal mixture to be conveyed with very constant pressure and considerably reduces or entirely prevents undesired effects, such as, for example, leakage or a reduced purification effect.
In order to achieve the most effective purification possible of the liquid-crystal mixture within the shortest possible time, it is provided that the liquid-crystal mixture is thoroughly mixed and homogenised before introduction into the first electrodialysis cell.
A device by means of which the process according to the invention can be carried out has a first electrodialysis cell having a supply line and a discharge line, enabling a liquid-crystal mixture to be passed through the first electrodialysis cell in a direction of passage, and a second electrodialysis cell having a supply line and a discharge line, which is adjacent to the first electrodialysis cell and is separated by a suitable ion-exchanger membrane, enabling a concentrate solution to be passed through the second electrodialysis cell. The first electrodialysis cell and the second electrodialysis cell are arranged between an anode/cathode arrangement in such a way that an electric field transverse to the direction of passage of the liquid-crystal mixture in the first electrodialysis cell can be generated by means of the anode/cathode arrangement.
The anode and the cathode are separated from the first electrodialysis cell and from the second electrodialysis cell in each case by an ion-exchanger membrane, which exchanges dissolved ions having a charge which has an opposite charge sign to the dissolved ions exchanged by the ion-exchanger membrane between the first electrodialysis cell and the second electrodialysis cell. For example, if a cation-exchanger membrane is located between the first electrodialysis cell and the second electrodialysis cell, the anode and the cathode are separated from the first and second electrodialysis cells by anion-exchanger membranes.
The ion-exchanger membranes can preferably have a heterogeneous design and contain ion-exchanger particles embedded in a base polymer, or alternatively can have a homogeneous design and consist of an ionic polymer. The electrode material used is preferably stainless steel, but also graphite or a suitable mixed oxide.
Spacing devices, which are known as spacers and also serve for effective fluid distribution within the electrodialysis cells, are arranged between the respectively adjacent ion-exchanger membranes. The spacers are made from an inert plastic material or plastic-material mixture, such as, for example, polyethylene, polyethylene and polyamide, or from polyvinyl chloride and polyethylene terephthalate. A typical thickness of suitable spacers is between 0.3 mm and 1.5 mm, preferably about 0.5 mm.
Low-pulsation and as far as possible constant-pressure pumps, such as, for example, gear pumps, are advantageously used for conveying the liquid-crystal mixture and the concentrate solution.
All components which come into contact with the liquid-crystal mixture, such as, for example, the electrodialysis cells, the ion-exchanger membranes, the spacers and the tubes used for the supply lines and discharge lines, are preferably made from an inert polymer or provided with a corresponding coating. A suitable inert polymer is, for example, PFA or PTFE.
Illustrative embodiments of the inventive idea are explained in greater detail below and are depicted in the drawing, in which:
A purification device 1, depicted by way of example in
A second electrodialysis cell 8, which is adjacent to the first electrodialysis cell 2, is separated from the first electrodialysis cell 2 by a suitable anion-exchanger membrane 9. The second electrodialysis cell 8 likewise has a supply line 10 and a discharge line 11, which are connected to a concentrate-solution reservoir 12, so that a concentrate solution 14 can be passed through the second electrodialysis cell 8 with the aid of a gear pump 13. The concentrate solution 14 used is deionised water.
The first electrodialysis cell 2 and the second electrodialysis cell 8 are arranged between an anode 15 and a cathode 16 in such a way that an electric field transverse to the direction of passage of the liquid-crystal mixture 7 in the first electrodialysis cell 2 can be generated by means of this anode/cathode arrangement.
The anode 15 and the cathode 16 are separated from the first electrodialysis cell 2 and from the second electrodialysis cell 8 in each case by a cation-exchanger membrane 17 and can be flushed continuously or on demand with transformer oil 19 with the aid of a transformer-oil circuit 18.
All components which come into contact with the liquid-crystal mixture 7, such as, for example, the electrodialysis cells 2 and 8, the ion-exchanger membranes 9 and 17, the spacers and the tubes used for the supply lines 3 and 10 and the discharge lines 4 and 11, are made from an inert polymer or provided with a corresponding coating. A suitable inert polymer is, for example, PFA or PTFE.
In order to carry out the purification process, a potential difference of, for example, 80 volts or 120 volts is generated between the anode 15 and the cathode 16 with the aid of a direct-voltage source. The gear pumps 6 and 13 are started and effect uniform passage of the liquid-crystal mixture 7 through the first electrodialysis cell 2 and of the concentrate solution 14 through the second electrodialysis cell 8. While the liquid-crystal mixture 7 flows through the first electrodialysis cell 2, ionised impurities are diverted by the electric field either in the direction of the second electrodialysis cell 8 at the anion-exchanger membrane 9, or, in the case of an opposite charge sign of the ionised impurity, in the direction of the cathode 16 at the cation-exchanger membrane 17 and are thereby removed from the liquid-crystal mixture 7 flowing through.
The liquid-crystal mixture can be passed through the first electrodialysis cell 2 over a sufficiently long period. While the purification process is being carried out, samples can be taken continuously or at time intervals in order to determine and monitor the purification of the liquid-crystal mixture 7 that has already been achieved.
The purification process according to the invention can be carried out using standard laboratory electrodialysis devices and merely requires continuous operation of the gear pumps. Correspondingly, the purification process can be carried out using simple equipment and inexpensively and facilitates very efficient purification of the liquid-crystal mixture 7. The efficiency can be increased further by additionally carrying out further purification processes based on other methods beforehand.
The purification process described above is particularly suitable for liquid-crystal mixtures comprising at least two organic substances, preferably mesogenic, in particular liquid-crystalline substances, where the organic substances are preferably selected from the compounds of the general formula I,
in which
—C≡C—, —CH═CH—, —CF2O—, —OCF2—, —OC—O— or —O—CO— in such a way that O atoms are not linked directly to one another, and one of the radicals R1 and R2 also denotes F, Cl, CN, SF5, NCS, SCN, OCN,
In the case where r+s+t=0, Z1 and Z4 are preferably selected in such a way that, if they do not denote a single bond, they are not linked to one another via two 0 atoms.
The liquid-crystal mixtures employed comprising the individual mesogenic substances may additionally also comprise one or more polymerisable compounds, so-called reactive mesogens (RMs), for example as disclosed in U.S. Pat. No. 6,861,107, in concentrations of, preferably, 0.1-5% by weight, particularly preferably 0.2-2% by weight, based on the mixture. Mixtures of this type can be used for so-called polymer stabilised VA (PS-VA) modes, negative IPS (PS-IPS) or negative FFS (PS-FFS) modes, in which polymerisation of the reactive mesogens is intended to take place in the liquid-crystalline mixture. The prerequisite for this is that the liquid-crystal mixture does not itself comprise any individual polymerisable substances.
The prerequisite for this is that the liquid-crystal mixture itself does not comprise any polymerisable components which likewise polymerise under the conditions where the compounds of the formula M polymerise.
The polymerisation is preferably carried out under the following conditions:
The polymerisable components are polymerised in a cell using a UV-A lamp of defined intensity for a defined period and applied voltage (typically 10 V to 30 V alternating voltage, frequencies in the range from 60 Hz-1 kHz). The UV-A light source employed is typically a metal-halide vapour lamp or high-pressure mercury lamp having an intensity of 50 mW/cm2. These are conditions where, for example, liquid-crystalline compounds containing an alkenyl or alkenyloxy side chain, such as, for example, the compound of the formula
do not polymerise.
The polymerisable mesogenic or liquid-crystalline compounds, also known as “reactive mesogens” (RMs), are preferably selected from the compounds of the formula II
Ra-A1-(Z1-A2)m-Rb II
in which the individual radicals have the following meanings:
NO2, a carbon group or hydrocarbon group, where the compounds contain at least one radical L, Ra and Rb which denotes or contains a P-Sp-group,
The polymerisable compounds may contain one polymerisable group (monoreactive) or two or more (di- or multireactive), preferably two, polymerisable groups.
Above and below, the following meanings apply:
The term “mesogenic group” is known to the person skilled in the art and is described in the literature, and denotes a group which, due to the anisotropy of its attracting and repelling interactions, essentially contributes to causing a liquid-crystal (LC) phase in low-molecular-weight or polymeric substances. Compounds containing mesogenic groups (mesogenic compounds) do not necessarily have to have an LC phase themselves. It is also possible for mesogenic compounds to exhibit LC phase behaviour only after mixing with other compounds and/or after polymerisation. Typical mesogenic groups are, for example, rigid rod- or disc-shaped units. An overview of the terms and definitions used in connection with mesogenic or LC compounds is given in Pure Appl. Chem. 73(5), 888 (2001) and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116, 6340-6368.
The term “spacer group”, also referred to as “Sp” above and below, is known to the person skilled in the art and is described in the literature, see, for example, Pure Appl. Chem. 73(5), 888 (2001) and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 116, 6340-6368. Unless indicated otherwise, the term “spacer group” or “spacer” above and below denotes a flexible group which connects the mesogenic group and the polymerisable group(s) in a polymerisable mesogenic compound (“RM”) to one another. Sp preferably denotes a single bond or a 1-16 C alkylene, in which one or more CH2 groups may be replaced by —O—, —CO—, —COO— or —OCO— in such a way that two 0 atoms are not connected directly to one another.
The term “organic group” denotes a carbon or hydrocarbon group.
The term “carbon group” denotes a mono- or polyvalent organic group containing at least one carbon atom which either contains no further atoms (such as, for example, —C≡C—) or optionally contains one or more further atoms, such as, for example, N, O, S, P, Si, Se, As, Te or Ge (for example carbonyl, etc.). The term “hydrocarbon group” denotes a carbon group which additionally contains one or more H atoms and optionally one or more heteroatoms, such as, for example, N, O, S, P, Si, Se, As, Te or Ge.
“Halogen” denotes F, Cl, Br or I.
The terms “alkyl”, “aryl”, “heteroaryl”, etc., also encompass polyvalent groups, for example alkylene, arylene, heteroarylene, etc.
The term “alkyl” in this application encompasses straight-chain and branched alkyl groups having 1 to 9 carbon atoms, preferably the straight-chain groups methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl and nonyl. Groups having 1 to 5 carbon atoms are particularly preferred.
The term “alkenyl” in this application encompasses straight-chain and branched alkenyl groups having 2 to 9 carbon atoms, preferably the straight-chain groups having 2 to 7 carbon atoms. Particularly preferred alkenyl groups are C2-C7-1E-alkenyl, C4-C7-3E-alkenyl, C5-C7-4-alkenyl, C6-C7-5-alkenyl and C7-6-alkenyl, in particular C2-C7-1E-alkenyl, C4-C7-3E-alkenyl and C5-C7-4-alkenyl. Examples of preferred alkenyl groups are vinyl, 1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hex-enyl, 1E-hept-enyl, 3-butenyl, 3E-pentenyl, 3E-hexenyl, 3E-heptenyl, 4-pentenyl, 4Z-hexenyl, 4E-hexenyl, 4Z-hep-tenyl, 5-hexenyl, 6-heptenyl and the like. Groups having up to 5 carbon atoms are particularly preferred.
The term “fluoroalkyl” in this application encompasses straight-chain groups having a terminal fluorine, i.e. fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluoro-butyl, 5-fluoro-pentyl, 6-fluorohexyl and 7-fluoroheptyl. However, other positions of the fluorine are not excluded.
The term “oxaalkyl” or “alkoxy” in this application encompasses straight-chain radicals of the formula CnH2n+1-O—(CH2)m, in which n and m each, independently of one another, denote 1 to 6. Preferably, n=1 and m=1 to 6.
The term “aryl” denotes an aromatic carbon group or a group derived therefrom. The term “heteroaryl” denotes “aryl” in accordance with the above definition containing one or more heteroatoms.
The polymerisable group P is a group which is suitable for a polymerisation reaction, such as, for example, free-radical or ionic chain polymerisation, polyaddition or polycondensation, or for a polymer-analogous reaction, for example addition or condensation onto a main polymer chain. Particular preference is given to groups for chain polymerisation, in particular those containing a C═C double bond or a —C≡C— triple bond, and groups which are suitable for polymerisation with ring opening, such as, for example, oxetane or epoxide groups.
The polymerisable compounds are prepared analogously to processes which are known to the person skilled in the art and are described in standard works of organic chemistry, such as, for example, in Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Thieme-Verlag, Stuttgart.
Typical and preferred reactive mesogens (RMs) are described, for example, in WO 93/22397, EP 0 261 712, DE 195 04 224, WO 95/22586, WO 97/00600, U.S. Pat. No. 5,518,652, U.S. Pat. No. 5,750,051, U.S. Pat. No. 5,770,107 and U.S. Pat. No. 6,514,578. Very particularly referred reactive mesogens are shown on Table E.
The process is used for the preparation of a mixture consisting of organic compounds, one or more of which are preferably mesogenic, preferably liquid-crystalline, per se. The mesogenic compounds preferably include one or more liquid-crystalline compounds. The process product is preferably a homogeneous, liquid-crystalline mixture. In the broader sense, the process also encompasses the preparation of mixtures which consist of organic substances in the homogeneous liquid phase and comprise additives which are insoluble therein (for example small particles). The process can thus also be used for the preparation of suspension-like or emulsion-like mixtures based on a continuous homogeneous organic phase. However, process variants of this type are generally less preferred.
By means of suitable additives, the liquid-crystal mixtures comprising at least two compounds of the formula I can be modified in such a way that they can be employed in any type of LCD display that has been disclosed to date, for example, ECB, VAN, IPS, FFS, TN, TN-TFT, STN, OCB, GH, PS-IPS, PS-FFS, PM-VA, PVA, PSA, PS-VA or ASM-VA displays.
The liquid-crystal mixtures may also comprise further additives known to the person skilled in the art and described in the literature, such as, for example, UV stabilisers, such as, for example, Tinuvin®, for example Tinuvin® 770, from BASF, antioxidants, such as, for example, Irganox®, for example Irganox® 1076 (octadecyl 3-(3,5-di-tert.butyl-4-hydroxyphenyl)propionate), from BASF, free-radical scavengers, nanoparticles, microparticles, one or more dopants, etc. For example, 0-15% of pleochroic dyes may be added, furthermore conductive salts, preferably ethyldimethyldodecylammonium 4-hexoxybenzoate, tetrabutylammonium tetraphenylboranate or complex salts of crown ethers (cf., for example, Haller et al., Mol. Cryst. Liq. Cryst. Volume 24, pages 249-258 (1973)) in order to improve the conductivity, or substances can be added in order to modify the dielectric anisotropy, the viscosity and/or the alignment of the nematic phases. Substances of this type are described, for example, in DE-A 22 09 127, 22 40 864, 23 21 632, 23 38 281, 24 50 088, 26 37 430 and 28 53 728.
Suitable stabilisers and dopants which can be combined with the compounds of the formula I in the electrodialysis cell during the preparation of the liquid-crystal mixtures are indicated below in Tables C and D.
The following examples are intended to explain the invention without limiting it. Above and below, percent data denote percent by weight; all temperatures are indicated in degrees Celsius.
Throughout the patent application, 1,4-cyclohexylene rings and 1,4-phenylene rings are depicted as follows:
The cyclohexylene rings are trans-1,4-cyclohexylene rings.
In the present application and in the following examples, the structures of the liquid-crystal compounds are indicated by means of acronyms, with the transformation into chemical formulae taking place in accordance with Tables A and B below. All radicals CnH2n+1 and CmH2m+1 are straight-chain alkyl radicals having n and m C atoms respectively; n, m, k and z are integers and preferably denote 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12. The term “(O)CmH2m-1” means OCmH2m+1 or CmH2m+1. The coding in Table B is self-evident.
In Table A, only the acronym for the parent structure is indicated. In individual cases, this is followed, separated from the acronym for the parent structure by a dash, by a code for the substituents R1*, R2*, L1* and L2*:
Preferred mesogenic or liquid-crystalline substances which are suitable for the preparation of liquid-crystal mixtures and can be used in the purification process according to the invention are listed, in particular, in Tables A and B:
Particular preference is given to liquid-crystalline mixtures which comprise at least one, two, three, four or more compounds from Table B besides one or more compounds of the formula I.
Table C indicates possible dopants, which are generally added to the liquid-crystalline mixtures. The mixtures preferably comprise 0-10% by weight, in particular 0.01-5% by weight and particularly preferably 0.01-3% by weight, of dopants.
Stabilisers, which can be added, for example, to the liquid-crystalline mixtures in amounts of 0-10% by weight, are shown below.
(n=1-12)
Suitable polymerisable compounds (reactive mesogens) for use in the mixtures according to the invention, preferably in PSA and PS-VA applications or PS-IPS/FFS applications, are shown below in Table E:
Table E shows example compounds which can preferably be used as reactive mesogenic compounds in the liquid-crystalline mixtures according to the invention. If the liquid-crystalline mixtures comprise one or more reactive compounds, they are preferably employed in amounts of 0.01-5% by weight. It may be necessary also to add an initiator or a mixture of two or more initiators for the polymerisation. The initiator or the initiator mixture is preferably added in amounts of 0.001-2% by weight, based on the mixture. A suitable initiator is, for example, Irgacure (BASF) or Irganox (BASF).
Suitable polymerisable compounds (reactive mesogens) for use in the mixtures according to the invention, preferably in PSA and PS-VA applications or PS-IPS/FFS applications, are shown below in Table E:
In a preferred embodiment, the liquid-crystalline mixtures comprise one or more compounds selected from the group of the compounds from Table E.
The following working examples are intended to explain the invention without restricting it.
Above and below, percent data denote percent by weight. All temperatures are indicated in degrees Celsius. m.p. denotes melting point, cl.p.=clearing point. Furthermore, C=crystalline state, N=nematic phase, S=smectic phase and I=isotropic phase. The data between these symbols represent the transition temperatures. Furthermore,
The following examples are intended to explain the invention without limiting it.
Above and below, percentages denote percent by weight. All temperatures are indicated in degrees Celsius.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS or FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS or FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS or FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS or FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for VA applications, of the composition
is purified using the process according to the invention.
Mixture Examples 1 to 17 may additionally also comprise one or more, for example one or two, stabiliser(s) and/or a dopant from Tables C and D.
A liquid-crystalline mixture, for example for TN applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PVA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention and 0.005% of STAB-35 is subsequently added.
A liquid-crystalline mixture, for example for PS-IPS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-IPS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN-TFT applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for IPS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PM-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for TN applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PA-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for FFS applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PM-VA applications, of the composition
is purified using the process according to the invention.
A liquid-crystalline mixture, for example for PS-FFS applications, of the composition
is purified using the process according to the invention.
The following mixtures are likewise purified using the process according to the invention:
The mixture according to Example 57 additionally comprises 0.025% of STAB-35.
The mixture according to Example 68 additionally comprises 2% of R-5011.
The mixture according to Example 84 additionally comprises 0.4% of RM-1.
The mixture from Example 86 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.3% of RM-1.
The mixture from Example 89 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.3% of RM-1.
The mixture from Example 90 additionally comprises 0.3% of RM-1.
The mixture from Example 91 additionally comprises 0.001% of STAB-35.
The mixture according to Example 95 additionally comprises 5% of RM-41.
The mixture according to Example 100 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.45% of RM-1.
The mixture according to Example 102 additionally comprises 0.04% of
and
0.01% of
The mixture according to Example 103 additionally comprises 0.04% of
and 0.01% of
The mixture from Example 104 additionally comprises 0.04% of
and 0.015% of
The mixture according to Example 105 additionally comprises 0.04% of
and 0.02% of
The mixture according to Example 106 additionally comprises 0.04% of
and 0.015% of
The mixture according to Example 107 additionally comprises 0.01% of
The mixture according to Example 113 additionally comprises 0.3% of RM-1.
The mixture according to Example 115 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.3% of RM-1.
The mixture according to Example 119 additionally comprises 0.01% of
The mixture from Example 120 additionally comprises 0.3% of
The mixture from Example 121 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate. BASF) and 0.45% of RM-1.
The mixture according to Example 143 additionally comprises 0.01% of
The mixture according to Example 157 additionally comprises 0.01% of
The mixture according to Example 157 additionally comprises 0.01% of
The mixture according to Example 180 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.3% of RM-1.
The mixture according to Example 181 additionally comprises 0.01% of
The mixture according to Example 185 additionally comprises 0.25% of RM-35
and 0.025% of
The mixture according to Example 186 additionally comprises 0.03% of
The mixture according to Example 186 additionally comprises 0.03% of
The mixture according to Example 189 additionally comprises 0.01% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.3% of RM-1.
The mixture according to Example 196 additionally comprises 0.04% of
and 0.015% of
The mixture according to Example 197 additionally comprises 0.04% of
and 0.015% of
The mixture according to Example 198 additionally comprises 0.25% of RM-41
The mixture according to Example 198 additionally comprises 0.3% of RM-17
The mixture according to Example 205 additionally comprises 0.015% of
and 0.015% of
The mixture according to Example 210 additionally comprises 0.25% of
and 0.25% of
The mixture according to Example 211 additionally comprises 0.04% of
and 0.02% of
The mixture according to Example 212 additionally comprises 0.25% of
The mixture according to Example 213 additionally comprises 0.2% of
The mixture according to Example 217 additionally comprises 0.04% of
The mixture according to Example 218 additionally comprises 0.04% of
The mixture according to Example 221 additionally comprises 0.25% of
The mixture according to Example 223 additionally comprises 0.001% of Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, BASF) and 0.4% of
The mixture according to Example 226 additionally comprises 0.3% of
The mixture according to Example 227 additionally comprises 0.04% of
and 0.015% of
The mixture according to Example 231 additionally comprises 0.04% of
and 0.02% of
The mixture according to Example 232 additionally comprises 10% of
The mixture according to Example 233 additionally comprises 0.04% of
and 0.02% of
The mixture according to Example 234 additionally comprises 0.04% of
and 0.02% of
The mixture according to Example 236 additionally comprises 0.015% of
The mixture according to Example 237 additionally comprises 0.015% of
The mixture according to Example 240 additionally comprises 0.008% of
The mixture according to Example 242 additionally comprises 0.25% of RM-41
The mixture according to Example 247 additionally comprises 0.03% of
and 0.4% of
The mixture according to Example 248 additionally comprises 0.005% of
The mixture according to Example 249 additionally comprises 0.015% of
The mixture according to Example 249 additionally comprises 0.005% of
Number | Date | Country | Kind |
---|---|---|---|
10 2013 021 279.0 | Dec 2013 | DE | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2014/003376 | 12/16/2014 | WO | 00 |