Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C43/00—Ethers; Compounds having groups, groups or groups
  • C07C43/02—Ethers
  • C07C43/20—Ethers having an ether-oxygen atom bound to a carbon atom of a six-membered aromatic ring
  • C07C43/205—Ethers having an ether-oxygen atom bound to a carbon atom of a six-membered aromatic ring the aromatic ring being a non-condensed ring
  • C07C43/2055—Ethers having an ether-oxygen atom bound to a carbon atom of a six-membered aromatic ring the aromatic ring being a non-condensed ring containing more than one ether bond
• • 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
  • C09K19/12—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings at least two benzene rings directly linked, e.g. biphenyls
• • 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
  • C09K19/14—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a carbon chain
• • 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
  • 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
  • C09K19/34—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring
  • C09K19/3441—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having nitrogen as hetero atom
  • C09K19/3444—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having nitrogen as hetero atom the heterocyclic ring being a six-membered aromatic ring containing one nitrogen atom, e.g. pyridine
• • 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
  • C09K19/34—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring
  • C09K19/3441—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having nitrogen as hetero atom
  • C09K19/345—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having nitrogen as hetero atom the heterocyclic ring being a six-membered aromatic ring containing two nitrogen atoms
  • C09K19/3458—Uncondensed pyrimidines

Definitions

• This invention relates to compounds forming a tilted smectic liquid crystal phase and to electrooptical devices containing a ferroelectric liquid crystal material.
• Ferroelectric behaviour has been observed in liquid crystal materials which possess a tilted chiral smectic phase.
• the liquid crystal is desirably in the smectic C phase, although other tilted smectic phases such as smectic I and smectic F phases can also form a ferroelectric system.
• the chirality may be present either intrinsically in the liquid crystal molecule or in a chiral dopant which may be added at about 5 - 203. to the liquid crystal material.
• suitable chiral dopants include the oct-2-yl esters of
• the material should possess a high spontaneous polarisation in order to be used in a ferroelectric liquid crystal display device.
• a ferroelectric liquid crystal display device Such a device containing for example a chiral smectic C (Sc*) liquid crystal should be constructed to permit the action of a direct electric field upon the ferroelectric dipole moment.
• the molecules in liquid crystal materials generally have a rigid core of known type, to opposite ends of which are attached two groups of various kinds.
• each of these groups is usually a straight or branched alyky or alkoxy group.
• a compound forming a tilted smectic liquid crystal phase has the general formula
• R! is an aliphatic radical containing carbon and hydrogen atoms and optionally one or more oxygen atoms each linked to separate carbon atoms and having a total number of carbon or of carbon and oxygen atoms not less than 1 and not more than 15;
• R! is preferably an alkyl or alkoxyalkyl radical, with up to. 7 carbon atoms, for example methyl, ethyl, prop l , butyl, pentyl , hexyl , heptyl methoxyethyl , ethoxyethyl , propoxyethyl or butoxethyl.
• Rl can be straight-chained or branched. Straight-chained groups are preferred. If R 1 is a branched radical containing an asymmetric carbon atom, such as but-2-yl, the compound may form a tilted chiral smectic phase and have ferroelectric properties without the need for admixture with optically active dopant.
• R 2 is preferably an alkyl, alkenyl, alkoxy, alkenyloxy, alkoxyalkoxy, alkoxycarbonyl , alkanoyloxy, or al koxyal koxyal koxy radical.
• R 2 contains an asymmetric carbon atom, the compound may similarly form a tilted chiral smectic phase without added dopant.
• Preferred chiral groups R 2 have the formula
• Q' is preferably -CH 2 -, -CH 2 CH 2 -, -CH 2 CH 2 CH 2 - or a single bond, particularly preferably a single bond.
• Y' is preferably CH3, -CN or Cl , particularly preferably CN.
• R 5 i s preferably straight -chai n or branched al kyl with 1 to 10, in particular with 1 to 7, C atoms. Of the compounds of the formula I, those in which X' and Y' are not simulataneously methyl are preferred.
• the core ⁇ Z ⁇ preferably contains at least two rings or ring systems, at least one of which is a carbocycl ic or heterocyclic aromatic ring or ring system, the rings or ring systems being l inked together by direct covalent bond or any of a wide range of linking groups known for the purpose, for example carbonyl oxy and ethyl ene groups.
• -Q_ ⁇ is a residue of bi phenyl , bi phenyl -4-yl benzoate, phenyl 4-benzoyl oxybenzoate or naphthalene.
• ⁇ 1 ⁇ is a di valent group of the formula wherein A 2 , A 3 and A 4 are each 1 ,4-phenylene which i s unsubstituted or substituted by one or two F and/or Cl atoms and/or CH 3 groups and/or CN groups , wherein one or two CH groups can al so be replaced by N, or 1 ,4-cyclohexylene, wherein one or two non- adjacent CH groups can al so be replaced by 0 atoms and/or S atoms , or piperidine-l ,4-diyl , l,4-bicyclo(2,2,2) octylene, naphthalene-2,6- diyl , decahydronaphthalene-2,6-diyl or 1,2,3,4,- tetrahydronaphthalene-2,6-diyl groups, and Z 1 and Z 2 are each -C0-0-, -C0-S-, -0-C0- ,
• Ph is a 1.4-phenylene group, which may be substituted (e.g. by fluorine) and wherein one or : two CH groups can al so be replaced by N
• Cy is a 1 ,4-cyclohexylene group, wherein one or two non-adjacent CH groups can also be replaced by 0 atoms
• Bi is a bicycl o (2,2,2) octylene group, n i s preferably 0.
• a 2 , A 3 and A 4 are preferably Cy or Ph.
• Ph preferably denotes a 1 ,4-phenylene (Phe) , a pyrimi dine-2,5-diyl (Pyr) , a pyridine-2,5-diyl (Pyn) , a pyrazine-3,6-diyl or a pyridazine-2,5-diyl group, particularly preferably Phe, Pyr or Pyn.
• the compounds according to the invention preferably contain not more than one 1,4-phenylene group wherein one or two CH groups are replaced by N. Cy preferably denotes a trans-l,4-cyclohe ylene group.
• Particularly preferred compounds of the formula I and of the above part formulae are those which contain a grouping -Ph-Ph-.
• -Ph-Ph- is preferably -Phe-Phe-, Phe-Pyr or Phe-Pyn.
• Particularly preferred groups are ⁇ _ ⁇ IX°>.
• the liquid crystal material is contained in a cell between rubbed polymer surfaces separated by a short distance, preferably not more than 2pm.
• Ferroelectric behaviour together with the high viscosity and long range order of the smectic liquid crystal phase permits both extremely short switching times under the action of a direct electric field upon the ferroelectric dipole moment and also bi stability.
• This combination of short addressing time and bistability opens up the possibility of a highly multiplexed flat panel display capable of video frame rates.
• the total number of addressed lines is limited by the response time of the optical effect which determines the frame time.
• Such a display has many possible applications ranging from an alphagraphic display for a word processor or portable computer to a full-colour flat panel television.
• the compounds of the formula I are prepared by methods which are known per se, such as are described in the l iterature (for example in the standard works, such as Houben-Weyl , Methoden der Organischen Chemie (Methods of Organic Chemi stry) , Georg-Thieme-Verlag, Stuttgart) , and in particular under reaction conditions which are known and suitable for the reactions mentioned. Variants which are known per se and are not mentioned here in more detai l can also be utilized.
• starti ng substances can al so be formed in situ such that they are not i solated from the reaction mixture but are immediately reacted further to give the compounds of the formula I.
• Suitabl e starting substances are avai lable in a large variety, e.g.
• transition temperatures of the product were determined by optical microscopy and differential thermal analysis, with the following results :- crystal to smectic K, 75°C; smectic K to isotropic, 118°C.
• the liquid crystal phase was proved to be smectic K by X-ray analysis.
• Example 1 The procedure of Example 1 was repeated using l-bromo-2-methoxyethane instead of l-bromo-2-ethoxyethane, and the structure of the product and its transition temperatures were determined in the same way:- crystal to smectic K, 127°C; smectic to isotropic, 139°C.
• 4-(2-Ethoxyethoxy)benzoic acid was prepared as follows. A mixture of 4-hydroxybenzoic acid (13.8 g), l-bromo-2-ethoxyethane (30.6 g), sodium hydroxide (8.8. g), ethanol (20 ml) and water (50 ml) was heated under reflux for 16 hours. Potassium hydroxide (5.6 g) in water (100 ml) was added to the reaction mixture and reflux continued. After 1 hour, while the mixture was cooling, concentrated hydrochloric acid was added to pH 2 - 3. Crystals appeared on continued cooling and were filtered off and dissolved at boiling point in water (350 ml) to which ethanol (100 ml) was subsequently added. The milky mixture was filtered and cooled and crystallization occurred to give white material m.p 133-135°C.
• Transition temperatures were determined as in previous examples (the compound may be polymorphic) :- solid to isotropic, 40.5 - 41.5°C; isotropic to nematic, 12.4°C.
• Example 3 The procedure of Example 3 was repeated using 4-nonyl phenol instead of 4-octylphenol to react with the acid. The structure of the product was determined in the same way.
• Transition temperature - solid to isotropic, 35 - 37°C. isotropic to nematic, 24.6°C.
• Example 3 The procedure of Example 3 was repeated using 4-hexyl -4' hydroxybi phenyl instead of 4-octyl phenol to react with the acid. The structure of the product was determined in the same way.
• Transition temperatures - solid to nematic, 107.0 - 107.2°C; nematic to isotropic, 165.3 -166.3°C; nematic to smectic C 91 -90°C.

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• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

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• 1988
  • 1988-05-11 JP JP63503934A patent/JPH01503386A/ja active Pending
  • 1988-05-11 KR KR1019890700046A patent/KR890701709A/ko not_active Application Discontinuation
  • 1988-05-11 GB GB08811130A patent/GB2205098A/en not_active Withdrawn
  • 1988-05-11 EP EP88904243A patent/EP0314735A1/de not_active Withdrawn
  • 1988-05-11 WO PCT/GB1988/000365 patent/WO1988008870A1/en not_active Application Discontinuation

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