Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
  • C09K19/10—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings
  • C09K19/20—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
  • C09K19/10—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings
  • C09K19/20—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers
  • C09K19/2007—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers the chain containing -COO- or -OCO- groups
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
  • C07C69/76—Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring
  • C07C69/84—Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring of monocyclic hydroxy carboxylic acids, the hydroxy groups and the carboxyl groups of which are bound to carbon atoms of a six-membered aromatic ring
  • C07C69/88—Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring of monocyclic hydroxy carboxylic acids, the hydroxy groups and the carboxyl groups of which are bound to carbon atoms of a six-membered aromatic ring with esterified carboxyl groups
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
  • C07C69/76—Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring
  • C07C69/84—Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring of monocyclic hydroxy carboxylic acids, the hydroxy groups and the carboxyl groups of which are bound to carbon atoms of a six-membered aromatic ring
  • C07C69/92—Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring of monocyclic hydroxy carboxylic acids, the hydroxy groups and the carboxyl groups of which are bound to carbon atoms of a six-membered aromatic ring with etherified hydroxyl groups
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K2019/0444—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit characterized by a linking chain between rings or ring systems, a bridging chain between extensive mesogenic moieties or an end chain group
  • C09K2019/0448—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit characterized by a linking chain between rings or ring systems, a bridging chain between extensive mesogenic moieties or an end chain group the end chain group being a polymerizable end group, e.g. -Sp-P or acrylate

Definitions

• the present invention relates to a process for the preparation of liquid-crystalline compounds of the formula I or mixtures of liquid-crystalline compounds of the formula I.
• P 1 , P 2 are hydrogen, -CC alkyl or reactive radicals, via which a polymerization can be brought about
• Y 1 , Y 2 single chemical bond, oxygen, sulfur, -O-CO-, -CO-O-, -O-CO-O-, -CO-NR-, -NR-CO-, -O-CO-NR -, -NR-CO-O- or -NR-CO-NR-,
• R is hydrogen or C] _- C alkyl
• Carbon chain can be interrupted by oxygen in ether function, sulfur in thioether function or by non-adjacent imino or -CC alkylimino groups,
• the invention further relates to compositions which
• Contain compounds of formula I and optionally further additives processes for producing coatings from the compounds prepared according to the process and their mixtures, optionally in each case in a mixture with further additives, and from the compositions and articles according to the invention which are coated by this process.
• the invention further relates to the use of the compounds prepared according to the process and their mixtures, if appropriate in each case in a mixture with further additives, and of the compositions according to the invention for the production of optical components and liquid-crystalline colorants, such liquid-crystalline colorants and aqueous emulsions or dispersions which compounds prepared according to the process and their mixtures, optionally in each case in a mixture with further additives, and compositions according to the invention, and pigments which are obtainable by polymerization of the compounds prepared according to the process and their mixtures, optionally in each case in a mixture with further additives, and the compositions according to the invention, the later
• Pigment size and shape either before polymerization by suitable processes or by comminution following the polymerization.
• a more elegant way of synthesis is therefore to build the target molecule from "inside” to "outside", i.e. the desired product is built up in successive steps from the component containing the finished mesogenic group M.
• This procedure describes e.g. the document WO 96/24647.
• dihydroxy compounds which contain the mesogenic group M are reacted with "spacer compounds" to the corresponding diethers and these are then converted in a further step to the target products with the desired end groups.
• WO 96/24647 also addresses mixtures of the liquid-crystalline compounds described therein. Mixtures of this type are interesting because the, often very narrow, liquid-crystalline phase range of pure liquid-crystalline compounds can be expanded by mixing with other liquid-crystalline compounds. However, undesirable by-products must also be expected in such mixtures.
• WO 96/04351 describes the preparation of liquid-crystalline mixtures by reacting one (several) reactive precursor (s) with several compounds (at least one compound) which carry the spacer unit and the reactive or unreactive end group. described. The main focus here is on the structure of the mesogenic group in one of the last reaction steps.
• An advantage of the production methods described in the documents WO 96/24647 and WO 96/04351 is that the mixtures do not first have to be prepared by mixing the liquid-crystalline pure components, but rather result as products of these production processes. However, the ratio of the resulting mixture components to one another is fixed by the implementation of the reaction components in the specified mixing ratios.
• Preferred reactive radicals P 1 and P 2 are
• radicals R are hydrogen or C ⁇ -C alkyl and may be the same or different.
• Particularly preferred polymerizable groups P 1 and P 2 are those which are accessible to radical polymerization, that is to say especially the olefinically unsaturated groups, and among these in combination with Y 1 and Y 2 have the groups 0 CH 3 0 Cl 0
• Hydrogen or C 1 -C 4 -alkyl such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl or t-butyl can be used as unreactive radicals P 1 and P 2 .
• These alkyl radicals mentioned can of course also stand for the radicals R mentioned previously for the preferred reactive radicals P 1 and P 2 as well as for the radicals R mentioned in the definition of the groups Y 1 and Y 2 .
• spacers A 1 and A 2 All groups known for this purpose can be considered as spacers A 1 and A 2 .
• the spacers contain 1 to 30, preferably 3 to 12, carbon atoms and consist of predominantly linear aliphatic groups. They can be interrupted in the chain, for example by non-adjacent oxygen or sulfur atoms or imino or alkylimino groups such as methylimino groups. Fluorine, chlorine, bromine, cyano, methyl and ethyl can also be used as substituents for the spacer chain.
• spacers are for example:
• both the radicals T and the groups Y 5 can each be the same or different from one another.
• R is preferably 1 or 2.
• radicals T can also be ring systems substituted by fluorine, chlorine, bromine, cyano, hydroxy or nitro.
• Preferred radicals T are:
• Preferred as mesogenic groups M are, for example
• each ring Z can carry up to three identical or different substituents from the following group:
• substituents for the aromatic rings are above all short-chain aliphatic radicals such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl , t-Butyl and alkoxy, alkoxycarbonyl, alkylcarbonyl, alkylcarbonyloxy, alkylcarbonylamino and monoalkylaminocarbonyl radicals which contain these alkyl groups.
• the outer benzene rings of the particularly preferred groups M preferably have the following substitution patterns:
• Mesogenediols whose mesogenic group M corresponds to the formula Ia and in which Y 5 is -COO- or -OOC- are advantageously used for the process-related preparation of the compounds I or their mixtures.
• These mesogen diols are usually built up by azeotropic esterification.
• p-hydroxybenzoic acid and (substituted) hydroquinone with the addition of xylene as entrainer and p-toluenesulfonic acid as catalyst, can be used in accordance with the following equations and, depending on the molar ratios used, either a mixture of "two" - robust "mesogen diols (equation 1):
• radicals R corresponds to the substituents of the rings Z mentioned above of the particularly preferred mesogenic groups M. If R in equation 1 is synonymous with hydrogen, the two resulting "dinuclear" mesogen diols are of course chemically identical.
• entrainer can also toluene, and other higher-boiling aromatics or mixtures of such hydrocarbons, which are used as under the names Solvesso ® or Aromatic ® are commercially available in addition to xylene.
• the acids on which the preferred leaving groups Y 32 and Y 42 are based can also preferably be used in pure form or as a concentrated aqueous solution. Concentrated sulfuric acid, boric acid or a mixture of these two acids can also be used advantageously.
• the ratio of starting materials to entrainer is not critical. Usually, however, about 200 to 350 g of the entrainer are used per 100 g of the starting materials.
• the amount of the catalyst used is about 1 to 10 g based on 100 g of the starting materials used.
• the reaction mixture consisting of starting materials, entrainer and catalyst, is rendered inert with nitrogen, heated and heated under reflux, the water being completely removed as an acetropic mixture with the entrainer.
• the implementation times are usually 4 to 12 hours. These times depend, however, on the amounts and the chemical nature of the starting materials and the entrainer used, as well as the amounts and the nature of the acid catalyst, and can therefore be exceeded or fallen short of in individual cases.
• the batch is cooled to room temperature and the crystalline crude product is washed with additional entraining agent or, if higher purities are desired, with solvents such as methanol or ethanol or their mixtures with water.
• the excess entrainer can also be removed by steam distillation, if appropriate with the addition of a commercially available defoamer, and the solid product can be isolated from water by filtration. Similar syntheses of such mesogen diols have already been described elsewhere (eg Kongas et al., Polym. Prep. (Am. Chem. Soc, Div. Polym. Chem.) 3J1- pp. 462-463 (1989) and Müller et al., DE -A 36 22 611).
• the leaving groups Y 32 , Y 42 of the compounds lilac and Illb use sulfonate groups which are derived from aliphatic, if appropriate partially or perfluorinated or aromatic sulfonic acid derivatives
• the compounds lilac and Illb are preferably prepared from hydroxy compounds and the acid chlorides for the preparation the sulfonic acid derivatives.
• the following implementation is intended to explain this using the example of hydroxyalkyl acrylates (equation 3), of which many representatives are readily available commercially.
• a 1 has the meaning as defined in the purple formula, -Y 1 -]? 1 corresponds to the grouping
• the solvent toluene can also be replaced by other solvents such as methylene chloride or ether.
• solvents such as methylene chloride or ether.
• further tertiary amines such as N, N-dimethylcyclohexylamine, trimethyl or triethylamine, but also alkali metal or alkaline earth metal carbonate or hydrogen carbonates are suitable as auxiliary bases, the potassium salts preferably being used here. Mixtures of such organic and inorganic bases can also be used.
• H 2 C CCO
• the etherification of the compounds Ila and / or Ilb with the compounds purple and / or Illb to the target compounds is usually carried out under the conditions of Williamson's ether synthesis.
• the bases used herein are preferably alkali metal and alkaline earth metal used, with Na 2 C0 3 and KC ⁇ 3 and CaC0 3 is particularly preferably used.
• the benzoic and acrylic ester groups present surprisingly remain intact, while these groups are Use of bases such as NaOH or KOH can be split partially or completely, depending on the amount of water and lye, among other things.
• Alkali bromides or iodides and tetraalkylammonium bromides or iodides can be added to catalyze the etherification reaction, potassium bromide or potassium iodide being used in the first case, tetrabutylammonium bromide or tetrabutylammonium iodide in the latter case.
• Suitable solvents are dimethylformamide, dimethyl acetamide, N-methylpyrrolidone or even dimethyl sulfoxide, with dimethylformamide preferably being used.
• the temperatures during the reactions according to the invention are generally from 70 to 110 ° C., the reaction times are usually from 4 to 24 hours, and the specified temperature ranges and time intervals can also be exceeded or fallen short of in individual cases.
• etherification reaction it is advantageous to carry out the etherification reaction under an inert atmosphere, for example a nitrogen atmosphere. Oxidative side reactions, especially on the mesogen diols, can be prevented.
• radical scavengers e.g. Commercially available nitroxyl compounds or phenol derivatives prevents the premature polymerization of the target compounds when using compounds of the formulas lilac and / or illb containing acrylate groups, especially when working up.
• nitroxyl compounds While the activity of phenol derivatives is generally increased in the presence of oxygen, nitroxyl compounds are also effective under an inert atmosphere, which is why they are preferably used in this case. If desired, one can of course also work in the preparation of the mesogen diols under inert conditions. The use of radical scavengers is then not necessary, but can be done if the etherification reaction follows in the sense of a one-pot reaction. As already mentioned above, preference is then given to adding, for example, nitroxyl compounds under inert conditions.
• compound lilac and / or Illb preferably have a halogen as the leaving group Y 32 or y 42 , particularly preferably Cl or Br, and is therefore virtually exclusively in the organic phase.
• organic bases examples of which are K 2 CO 3 or tetraalkylammonium hydroxides such as tetramethyl or tetraethylammonium hydroxide, these are almost exclusively in the aqueous phase.
• the mesogen diol When the mesogen diol is added, it is converted into its mono or dianion, which is only slightly soluble in the organic phase, but because of its lower solvation it has a higher nucleophilicity and therefore with the halogen compound dissolved therein without competing with the base anion have to react.
• compositions are also claimed according to the invention which are
• Liquid-crystalline compounds and mixtures of liquid-crystalline compounds which correspond to the compounds of the formula I but have reactive end groups on both molecules are known, for example, from WO 95/22586, WO 95/24454 and WO 96/24647.
• the proportions of compounds I terminated once or twice with radicals P 1 , P 2 equal to hydrogen or C 3 -C 4 -alkyl in the above compositions according to the invention allow their properties, such as, for example, the liquid-crystalline phase width or viscosity, to be adapted to the particular requirements.
• the properties of the Polymers obtained in such compositions For example, their hardness, elasticity, glass transition temperature as well as liquid and gas permeability can be varied due to the changed degree of crosslinking. Examples of simply unreactive (or equivalently simply reactive) components (i) are
• compositions according to the invention in which in at least one compound of component (i) at least one of the radicals P 1 , P 2 is hydrogen or C 1 -C 4 -alkyl, can also have compounds with different mesogenic groups M.
• compositions are also claimed which are obtainable by
• Component (iii) of the composition obtainable according to the invention which can be obtained in this way, can be regarded as a special component (i) of the corresponding composition according to the invention, in which certain compounds of the formula I are present in a fixed manner, both in terms of their identity and their mixing ratio to one another.
• the identity and the ratio of the compounds of the formula I to one another in component (iii) is defined by the ratio of the starting compounds of the formulas Ila and / or Ilb and lilac or / and Illb to one another.
• the mesogen diol will be present, at least in part, as a mono- or dianion.
• mixtures of several mesogen diols can also be used.
• several different components (iii) obtained in this way can also be combined with one another in any like to mix the ratio and possibly add other additives (iv).
• p2- ⁇ 2- 2 is a lower alkyl group such as methyl, ethyl or propyl, so is preferably carried out the reaction according to variant b) of the inventive method, that is, at least one compound of formula IIb with one or more compounds of formula IIIa implemented.
• P 2 -Y 2 -A 2 is an alkyl group such as butyl or higher homologs
• the procedure according to variant a) of the process according to the invention is preferred, ie a compound of the formula Ila is preferably used, for example, with butyl chloride, butyl bromide and others around.
• compositions according to the invention which are:
• T and Y 5 have the meaning as in formula Ia and r ', r "have the same meaning as r in formula Ia,
• compositions are also claimed according to the invention which are obtainable by
• residues P 1 and P 2 each represent reactive residues and at least two different mesogenic groups M of the formulas Ia '
• T and Y 5 have the meaning as in formula Ia and r ', r "have the same meaning as r in formula Ia,
• component (viii) of the composition obtained can be regarded as a special component (v) of the compositions according to the invention.
• compositions according to the invention and those obtainable according to the invention contain only direactive compounds I, that is to say only compounds in which both radicals P 1 and P 2 represent identical or different reactive groups, and also at least two compounds of the formula I which have different mesogenic groups M.
• the mesogenic groups then differ in terms of group Y 5 , that is
• component (v) a composition according to the invention is provided, in accordance with the reaction described above, component (vii) a composition obtainable according to the invention is determined by the spectrum of the different products (here, for example, compounds bi to b 8 ) and their percentages. Are in parentheses. the theoretically expected percentages are given after the formulas of the compounds bi to b 8 . The actual proportions can of course differ from these values due to the different reactivities of the starting and intermediate products.
• Example b) in a molar ratio of 50%: 50% with the same mixture of the compounds b 'and b''as in Example b) in stoichiometric amounts, the following compounds are obtained under the conditions mentioned in Example b):
• R has the meaning of the possible substituents of the rings Z in the particularly preferred mesogenic groups M already described further above.
• the compounds ds and d 6 and d and d 8 are of course identical in each case when R is hydrogen.
• the different solubilities of the starting diol and the monohydroxy intermediate in different solvents can be used to produce such monools and one can work with a multiple excess of the diol compared to the purple (or Illb) compound used , which favors simple versus double substitution of the diol.
• the excess diol can then either be recovered from the filtrate or precipitated out by adding a suitable diluent, in which case the monohydroxy intermediate is obtained as a solid or is soluble in the diluent.
• compositions are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which are claimed which
• (x) optionally contain further additives.
• compositions are also claimed which are obtainable by
• one or more compounds of the formula IIb are reacted with a maximum of two different compounds of the formula purple or
• Component (xi) of the compositions obtainable according to the invention is obtained by reacting one or more mesogen diols with a purple compound (or equivalent Illb) or a binary mixture of purple compounds and Illb. It is of course important here that when a compound lilac is used, it has a reactive radical P 1 , since otherwise the compounds I present in component (xi) can no longer be subjected to polymerization in the sense of the present invention. Of course, this also applies analogously to the compounds I of component (ix) of the compositions according to the invention.
• the type, number and ratio of compounds I of component (xi) of the compositions obtainable according to the invention are in turn determined by the compositions used Educts and their relationships to one another are determined. For example, here is the stoichiometric conversion of the diol
• component (xi) of a composition obtainable according to the invention for example consisting of the compounds ei to e 4 in the stated (theoretical) proportions
• component (xi) of a further composition obtainable according to the invention for example consisting of the compounds ⁇ to f 8 in the specified (theoretical) proportions
• a mixture of compounds I is obtained which is to be understood as component (ix) of the compositions according to the invention.
• component (ix) with the compounds of the formula I present therein in a special ratio can generally not be produced by a single, targeted reaction of mesogen diols with the corresponding compounds lilac and Illb.
• compositions according to the invention and those obtainable according to the invention can in each case be mixed with one another or with one another in order, for example, Adapt properties such as viscosity, degree of crosslinking of the polymers produced therefrom, liquid-crystalline phase widths, etc. to the respective requirements.
• the compounds of the formula I prepared according to the process or the mixtures of such compounds and the compositions according to the invention and the compositions obtainable according to the invention can contain further additives.
• One or more chiral compounds can serve as such.
• cholesteric, liquid-crystalline phases are created, which above all have interesting optical properties and reflect light of different wavelengths, for example, depending on the viewing angle.
• Such liquid crystal compositions are used in particular as cholesteric liquid crystalline colorants.
• Particularly suitable chiral components are those which, on the one hand, have great twistability and, on the other hand, are readily miscible with the liquid-crystalline compounds without disturbing the liquid-crystalline phase structure.
• Preferred chiral compounds are, for example, those of the general formulas Ib, Ic, Id, Ie
• Residues X are for example
• L is C 1 to C 4 alkyl, C x C alkoxy, halogen, COOR, OCOR, CONHR or NHCOR and R is C 1 -C 4 alkyl.
• liquid-crystalline compounds of the formula I or their mixtures prepared in accordance with the process and the compositions according to the invention and those obtainable according to the invention contain the chiral compounds mentioned in a proportion of 0.001 to 40% by weight, based on the total amount of the mixtures or compositions.
• Liquid crystalline compounds or mixtures thereof which are listed in the documents WO 95/22586, WO 95/24454, WO 95/24455, WO 96/30352 and WO 97/00600, or liquid crystalline mixtures which correspond to the Processes described in WO 96/04351 were prepared.
• the liquid-crystalline order state can be fixed.
• the polymerization can be carried out e.g. thermally or photochemically.
• Other monomers can also be copolymerized together with the liquid-crystalline compounds, mixtures or compositions.
• These monomers can be other polymerizable liquid crystalline compounds such as e.g. the liquid-crystalline compounds described in the publications cited above, chiral compounds, which are likewise preferably polymerized covalently, or customary crosslinking agents. Possible monomers are:
• vinyl aromatic compounds such as styrene or styrene derivatives of the general formula S 2
• S 1 and S 2 are hydrogen or C 1 -C 6 -alkyl
• Ci to C alkyl esters of acrylic acid, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, ethylhexyl acrylate and the corresponding esters of methacrylic acid and Cyanoacrylic acid; also the glycidyl esters, glycidyl acrylate and methacrylate.
• Crosslinking agents which can be used are bifunctional or polyfunctional compounds having at least 2 olefinic double bonds, for example divinyl esters of
• Dicarboxylic acids such as succinic acid and adipic acid, diallyl and divinyl ethers of bifunctional alcohols such as ethylene glycol and butane-1,4-diol, methacrylic acid esters or acrylic acid esters of polyfunctional alcohols, especially those which contain no further functional groups or at most ether groups in addition to the hydroxyl groups.
• bifunctional alcohols such as ethylene glycol, propylene glycol, and their more highly condensed representatives, e.g.
• alkoxylated phenolic compounds such as ethoxylated or propoxylated bisphenols, cyclohexanedimethanol, trifunctional and higher-functional alcohols, such as glycerol, triethanediol, trimethylolpropane, trimethylolpropane Pentaerythritol, ditrimethylolpropane, dipentaerythritol, sorbitol, mannitol and the corresponding alkoxylated, in particular ethoxy and propoxylated alcohols.
• polyester (meth) acrylates which are the (meth) acrylic esters of polyesterols.
• polyesterols examples are those which can be prepared by esterifying polycarboxylic acids, preferably dicarboxylic acids, with polyols, preferably diols.
• the starting materials for such hydroxyl-containing polyesters are known to the person skilled in the art.
• dicarboxylic acids succinic acid, glutaric acid, adipic acid, sebacic acid, o-phthalic acid, their isomers and hydrogenation products, and esterifiable derivatives such as Anhydrides or dialkyl esters of the acids mentioned are used.
• Suitable polyols are the above-mentioned alcohols, preferably ethylene glycol, propylene glycol-1, 2 and -1.3, butanediol-1, 4, hexanediol. -1.6, neopentyl glycol, cyclohexanedimethanol and polyglycols of the ethylene glycol and propylene glycol types.
• crosslinking agents may e.g. are epoxy or urethane (meth) acrylates.
• Epoxy (meth) acrylates are e.g. those as are obtainable by reaction of epoxidized olefins or poly- or diglycidyl ethers, such as bisphenol A diglycidyl ether, with (meth) acrylic acid, which are known to the person skilled in the art.
• Urethane (meth) acrylates are, in particular, reaction products of hydroxyalkyl (meth) acrylates with poly- or diisocyanates which are also known to the person skilled in the art.
• crosslinking agents are 1,4-divinylbenzene, triallyl cyanurate, acrylic esters of tricyclodecenyl alcohol of the formula below
• o- CO- CH CH 2 or o- CO- CH : CH 2
• dihydrodicyclopentadienyl acrylate as well as the allyl esters of acrylic acid, methacrylic acid and cyacrylic acid.
• crosslinking agent crosslinking monomer
• its amount must be adapted to the polymerization conditions in such a way that on the one hand a satisfactory desired effect is achieved, but on the other hand the liquid-crystalline phase behavior is not impaired too much.
• the amount of crosslinking agent that may be used generally depends on the use of the polymers. A larger amount of crosslinking agent can be advantageous for the production of pigments and a smaller amount of crosslinking agent for the production of thermoplastic layers.
• the amount of crosslinking agent can usually be determined by a few preliminary tests. Usually, however, an attempt will be made to keep the proportion of crosslinking agent (crosslinking monomer) small or to withdraw it entirely.
• a further modification of the polymerization products prepared from the liquid-crystalline compounds, mixtures or compositions is possible by adding polymeric auxiliaries, such as flow control agents, defoamers, deaerators, rheology aids or adhesion promoters, before the polymerization.
• Such auxiliaries should preferably either be soluble in the starting mixtures or else in an organic solvent compatible with the starting mixtures.
• Typical representatives of such polymeric auxiliaries are, for example, polyesters, cellulose esters, polyurethanes and polyether- or polyester-modified or also unmodified silicones.
• the amount of polymeric adjuvant to be added for the desired purpose, its chemical nature and possibly still the amount and type of solvent are generally familiar to the person skilled in the art or can likewise be determined experimentally by a few preliminary experiments.
• photoinitiators can be added as further additives.
• examples include the substances commercially available under the brand names Lucirin ® , Irgacure ® and Darocure ® , such as Lucirin ® TPO, Irgacure ® 184, Irgacure ® 369, Irgacure ® 907 and Darocure ® 1173.
• the initiators are used in customary amounts used, which corresponds to a proportion of about 0.5 to 5.0% by weight of the mixture or composition to be polymerized.
• Compounds which are incorporated into the process and their mixtures, and the compositions according to the invention and those obtainable according to the invention, can also be admixed with further additives which are incorporated noncovalently into the polymer network.
• these can also be commercially available nematic liquid crystals.
• additives can also be pigments, dyes and fillers.
• organic compounds include, for example, pigments or dyes from the class of monoazo pigments, monoazo dyes and their metal salts, disazo pigments, condensed disazo pigments, isoindoline derivatives, derivatives of naphthalene or perylene tetracarboxylic acid, anthraquinone pigments, thioindridone derivatives, azomacido derivative, azomido derivatives Dioxazines, pyrazoloquinazolones, phthalo- cyanine pigments or basic dyes such as triarylmethane dyes and their salts.
• pigments or dyes from the class of monoazo pigments, monoazo dyes and their metal salts, disazo pigments, condensed disazo pigments, isoindoline derivatives, derivatives of naphthalene or perylene tetracarboxylic acid, anthraquinone pigments, thioindridone derivatives, azomacido
• Iriodin ® and Paliocrom ® commercially available pearlescent and effect pigments.
• crosslinking agents and / or monomers and / or one or more of the chiral compounds also described above are added to the liquid-crystalline compounds or their mixtures and to the compositions according to the invention and those obtainable according to the invention, the latter are present in a proportion of 0 to 50% by weight, preferably 0 to 10% by weight.
• the proportion of crosslinking agents and / or monomers is 0 to 50% by weight, preferably 0 to 20% by weight, the sum of the proportions of the liquid-crystalline compounds, the crosslinking agents and / or monomers and the chiral compounds of course being 100% by weight -% must complete and the proportions relate to the total amount of the mixtures obtained in this way.
• a process for printing objects or for producing coatings with a liquid-crystalline order on articles is further claimed, which is characterized in that a liquid-crystalline compound of the formula I or mixtures of compounds of the formula I, prepared by the process according to the invention, if appropriate in a mixture with further additives, or applying compositions according to the invention or those obtainable according to the invention to a substrate, optionally providing orientation and then polymerizing the compounds or mixtures of the compounds applied to the substrate, optionally in a mixture with further additives, or compositions.
• the liquid-crystalline orientation either occurs spontaneously during application or is achieved by known physical methods such as, for example, doctoring or application of an electrical or magnetic field. If, for example, the use of the compounds prepared according to the process and their mixtures and the compositions according to the invention and obtainable according to the invention in the field of screen printing or flexographic printing is thought of, their viscosity can be reduced by adding diluents. Apart from the use of rheology aids and additives with a similar effect, another possibility for influencing the viscosities of the liquid-crystalline compounds, mixtures and compositions is to prepare mixtures of those compounds which differ in the number of nuclei of their mesogenic groups M.
• liquid-crystalline compounds of the formula I prepared according to the process, optionally in a mixture with further additives, or the compositions according to the invention or the compositions obtainable according to the invention for the production of optical components, such as e.g. Filters or polarizers for LCD displays, as well as for the production of liquid crystalline colorants, e.g. can be used in the printing sector or automotive painting technology.
• optical components such as e.g. Filters or polarizers for LCD displays
• liquid crystalline colorants e.g. can be used in the printing sector or automotive painting technology.
• liquid-crystalline colorants are also claimed which contain liquid-crystalline compounds of the formula I or a mixture of liquid-crystalline compounds of the formula I, prepared by the processes according to the invention, optionally in a mixture with further additives, or compositions obtainable according to the invention or according to the invention.
• Emulsions and dispersions are increasingly being used with regard to low-solvent and thus, among other things, more environmentally friendly and user-friendly formulations. As a rule, these have significantly lower viscosities than conventional formulations and are therefore particularly interesting with regard to painting using spraying techniques.
• aqueous emulsions or dispersions are further claimed, the liquid crystalline compounds of formula I or. a mixture of liquid-crystalline compounds of the formula I, prepared by the process according to the invention, if appropriate in a mixture with further additives, or compositions according to the invention or obtainable according to the invention and further auxiliaries customarily used for the preparation of emulsions or dispersions.
• Dispersions which include Containing liquid-crystalline compounds is set out, for example, in WO 96/02597 and can also be applied analogously to the dispersions and emulsions claimed here.
• the aqueous emulsions and dispersions according to the invention can, in addition to the liquid-crystalline compounds and optionally other additives, such as the chiral compounds, crosslinking agents, monomers, pigments, dyes, fillers, processing aids or photoinitiators mentioned, if desired, contain additional auxiliaries, such as e.g. Sunscreens and preservatives.
• additional auxiliaries such as e.g. Sunscreens and preservatives.
• water-soluble high molecular weight organic compounds with polar groups such as polyvinyl pyrrolidone, copolymers of vinyl propionate or
• Acetate and vinyl pyrrolidone, partially saponified copolymers of an acrylic ester and acrylonitrile, polyvinyl alcohols with different residual acetate content, cellulose ether, gelatin or mixtures of these substances are used.
• Particularly preferred emulsifiers and / or dispersants with the function as protective colloids are polyvinyl alcohol with a residual acetate content of less than 35, in particular 5 to 30 mole percent and / or a vinyl pyrrolidone / vinyl propionate copolymer with a vinyl ester content of less than 35, in particular 5 to 30 percent by weight.
• Nonionic and, in special cases, ionic emulsifiers / dispersants can be used.
• Preferred dispersants are longer-chain alcohols or phenols of different degrees of ethoxy and / or propoxylation (adducts of 4 to 50 mol of ethylene oxide and / or propylene oxide).
• Combinations of the abovementioned protective colloids with such emulsifiers / dispersants are particularly advantageous since they give very fine-particle emulsions / dispersions.
• emulsifiers / dispersants are, for example, dihexylsulfosuccinate, sulfosuccinate half-esters, the sodium salts of dodecylbenzenesulfonic acid and pentadecanesulfonic acid,
• Potassium oleate sodium lauryl sulfate, alkyl polyglycosides, isooctyl phenol, isononyl phenol, C 2 -C 8 fatty alcohols and fatty alcohol alkoxy latex.
• Polysiloxane-based emulsifying / dispersing aids are also particularly suitable.
• emulsifying / dispersing agents described are suitable for the preparation of oil-in-water emulsions. However, it is also possible to borrow emulsions or dispersions based on water-in-oil emulsions. For such emulsions or dispersions, emulsifiers and emulsifier mixtures such as those e.g. are described in EP-A 0 623 630.
• Suitable emulsifying / dispersing agents are also sorbitan monostearate, sorbitan monopalmitate, sorbitan tristearate, sorbitan mono oleate, sorbitan sesquioleate, polyoxyethylene sorbitol ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether and polyoxyethylene lenoleyl ether.
• the emulsions according to the invention can also be mini-emulsions.
• Mini emulsions have the advantage of forming particularly stable emulsions and are therefore particularly stable in storage.
• the emulsions described above which typically have droplet diameters in the micrometer range, are homogenized using a high-pressure homogenizer. In this way, emulsions with a droplet diameter in the range of a few hundred nm are obtained, in which no phase separation can be observed for weeks.
• the liquid-crystalline compounds or their mixtures if appropriate in a mixture with further additives, or compositions, if desired mixed with a small amount of a solvent such as tetrahydrofuran, dioxane, acetone, methyl ethyl ketone, the propanols, the butanols, ethyl acetate, butyl acetate, methylene chloride, the xylenes or toluene or else water, in order to reduce the viscosity.
• a solvent such as tetrahydrofuran, dioxane, acetone, methyl ethyl ketone, the propanols, the butanols, ethyl acetate, butyl acetate, methylene chloride, the xylenes or toluene or else water, in order to reduce the viscosity.
• liquid-crystalline compounds, mixtures or compositions are preferably admixed directly with the emulsifying / dispersing aid, which can also be added as an aqueous solution.
• the resulting mixture is homogenized intensively, for example by stirring.
• water is added and again thoroughly homogenized.
• the amount of water depends on the desired use. 20 to 80% by weight, particularly preferably 40 to 60% by weight, of water are preferably added, based on the total amount of the finished emulsion or dispersion.
• the emulsions / dispersions can be diluted with water, to which an emulsifying / dispersing aid can in turn be added, to the desired viscosity and colorant concentration.
• thermal processes or radiation processes such as light or electron beam curing are possible, as for the coating mixtures, depending on the type of polymerizable groups.
• the addition of polymerization initiators, as described for the coating mixtures, is also advantageous for the curable dispersion films.
• dispersion coatings are easy to process.
• the dispersions have low viscosities, can be prepared without solvents and therefore do not require any ventilation equipment and can be applied by all known, simple application techniques such as brushing, rolling, spraying, printing, dipping or through a casting gap.
• the coating process according to the invention also gives rise to spontaneous orientation from the dispersion, so that, in the presence of suitable additives, such as e.g. chiral
• pigments which are obtainable by polymerizing the compounds of the formula I prepared according to the process, if appropriate in a mixture with further additives, or the compositions according to the invention or those obtainable according to the invention as a thin film on a substrate, detaching and dissolving the polymer composition from the substrate Crushed pigment particle size.
• the film thicknesses are selected during production such that the finished pigment particles have thicknesses of 0.5 to 50 ⁇ m, preferably 1 to 25 ⁇ m, particularly preferably 2 to 10 ⁇ m.
• the mean diameters of the pigment particles are values which correspond to 3 to 100 times the thickness of the pigment particles, ie the ratio of the mean diameter to the thickness of the pigment particles corresponds to 3: 1 to 100: 1.
• a ratio of 4: 1 to 25: 1 is preferred, particularly preferably 5: 1 to 15: 1.
• the film can be applied, for example, by using a doctor blade. Typical gap widths are 7.5 to 400 ⁇ m.
• Casting techniques which are common in the production of magnetic tapes, for example, allow film thicknesses of a few ⁇ m to be set. Depending on which volatile additives are present in which quantities during film production, the thicknesses in the finished pigment particle are more or less large fractions of these "wet film thicknesses".
• Pigments which can be obtained by liquid-crystalline compounds of the formula I or a mixture of liquid-crystalline compounds of the formula I prepared by the process according to the invention, optionally in a mixture with further additives, or compositions according to the invention or obtainable according to the invention are therefore particularly preferred Applies printing processes to a substrate, the printing process specifying the subsequent pigment shape and pigment dimensions, subjecting said compounds, mixtures or compositions to polymerization and then detaching the polymeric products from the substrate.
• the pigment dimensions the same applies as mentioned above.
• the pigments obtainable according to the invention can be used not only in conventional but also in water-based paints. Examples of such formulations in which the inventive appropriate pigments can be used as effect generators are described in the documents WO 95/29961 and WO 95/29962.
• he 77 i means that the crystalline phase (he) at 77 ° C in an isotropic phase (i) ⁇ melt.
• phase behavior of the compounds or mixtures was examined using polarization microscopy.
• the temperature was checked using a heating table of the type FP 80/82 from Mettler.
• the compounds were prepared analogously to preparation variants A) or B) of Example Ia using the respective molar amount of methoxyhydroquinone or hydroquinone.
• the mixture of the two isomeric hydroxy starting compounds results from the reaction of acrylic acid (or an acrylic acid derivative) with a mixture of the two isomeric diols, which can be obtained, for example, in the reaction of propylene oxide with water.
• connection purple or Illb
• leaving group Y 32 or Y 42
• Example 6a Analogously to Example 6a, the compound is obtained using the corresponding molar amount of methacrylic acid
• connection purple or Illb
• leaving group Y 32 or Y 42 C1 ⁇
• the mixture is heated 410 g (3 mol) of 6-chloro-l-hexanol, hexane 500 ml of methylcyclohexane, 247 ml (3.6 mol) of acrylic acid, 2.5 g of methoxyphenol, 0.3 g Kerobit ® BHT and 10 g (0 , 05 mol) of p-toluenesulfonic acid monohydrate under reflux for 3 h, about 64 ml of water being removed.
• the mixture is then cooled to RT and one liter of ethyl acetate is added to the mixture.
• the organic phase is separated off and shaken twice with water and twice with saturated
• Example 7a Analogously to Example 7a, the compound is obtained using the corresponding number of moles of methacrylic acid
• Table 2 lists the purple compounds and their molar proportions in the respective total mixtures, and the phase behavior of the mixtures of compounds of the formula I resulting from the reactions.
• Example lc with mixtures of compounds of the formula purple (or IIIb).
• Table 3 the molar proportions of the above mesogen diols and the molar proportions of the compounds used are purple in their respective for the preparation the starting mixtures used in the liquid-crystalline mixtures and the phase behavior of the resulting liquid-crystalline mixtures of compounds of the formula I are listed.
• Table 4 lists the proportions by weight of the mixtures from Example 33 for compound Zi or mixture Z in the resulting overall mixture, as well as their phase behavior and viscosities.
• the viscosity was determined using a "Rheometrics Dynamic Spectrometer" from Rheometrics in a cone-plate geometry at room temperature.

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• 1997
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