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    112.
    发明专利
    未知

    公开(公告)号：NO902795D0

    公开(公告)日：1990-06-22

    申请号：NO902795

    申请日：1990-06-22

    Applicant: HOECHST AG

    Inventor： ESCHER CLAUS ,  HEMMERLING WOLFGANG ,  ILLIAN GERHARD ,  HARADA TAKAMASA ,  MURAKAMI MIKIO

    IPC: G02F1/1337 ,  C09K19/02 ,  C09K19/34 ,  C09K19/58 ,  G02F1/137 ,  G02F1/141 ,  G02F

    Abstract: Liquid-crystalline materials are becoming increasingly important in electrooptical switching and display devices. Recently, ferroelectric liquid-crystalline mixtures have also been investigated widely and employed in displays. A particularly important physical parameter for describing FLC mixtures is the spontaneous polarisation (Ps). On the one hand, a high spontaneous polarisation results in short response times, but on the other hand, high Ps values result in optical hysteresis, which causes, inter alia, so-called "ghost images". The use of FLC mixtures of high spontaneous polarisation (Ps 20 nC/cm ) and a natural helical pitch of less than half the layer thickness in an SSFLC display having a layer thickness of from 1 to 10 mu m allows the problem of optical hysteresis to be circumvented, in spite of the high spontaneous polarisation. FLC mixtures in which Ps is > 40 nC/cm can also be switched under these conditions.

    113.
    发明专利
    未知

    公开(公告)号：DE69128625D1

    公开(公告)日：1998-02-12

    申请号：DE69128625

    申请日：1991-07-17

    Applicant: HOECHST AG

    Inventor： MURAKAMI MIKIO ,  HARADA TAKAMASA

    IPC: C08G63/60 ,  C09K19/02 ,  C09K19/56 ,  G02F1/1337

    Abstract: PCT No. PCT/EP91/01339 Sec. 371 Date Jan. 12, 1993 Sec. 102(e) Date Jan. 12, 1993 PCT Filed Jul. 17, 1991 PCT Pub. No. WO92/01728 PCT Pub. Date Feb. 6, 1992.A liquid-crystal display device having a liquid-crystal layer held between a pair of substrates each having a transparent electrode and an alignment film formed successively on the inner surface, characterized in that the material of the alignment film on at least one of the opposing faces between the substrates is a polymer having recurring units (I, II and III), the recurring unit (I) being represented by formula (A), (A) recurring unit II being a dioxyaryl portion represented by the formula -O-Ar-O- (where Ar is a divalent group having at least one aromatic ring which may contain at least one substituent selected from a C1-4 alkyl group, a C1-4 alkoxy group, a halogen, a phenyl and a substituted phenyl), and recurring unit (III) being a dicarboxyaryl portion represented by formula (B) (B) (where Ar' may be the same as or different from Ar and has the same meaning as Ar).

    114.
    发明专利
    未知

    公开(公告)号：DE59009244D1

    公开(公告)日：1995-07-20

    申请号：DE59009244

    申请日：1990-03-21

    Applicant: HOECHST AG

    Inventor： DUEBAL HANS-ROLF ,  ESCHER CLAUS ,  HARADA TAKAMASA ,  HEMMERLING WOLFGANG ,  ILLIAN GERHARD ,  MUELLER INGRID ,  MURAKAMI MIKIO NEW TOWN BLG ,  OHLENDORF DIETER ,  WINGEN RAINER

    IPC: C09K19/42 ,  C09K19/34 ,  C09K19/46 ,  C09K19/58

    Abstract: PCT No. PCT/EP90/00457 Sec. 371 Date Oct. 28, 1991 Sec. 102(e) Date Oct. 28, 1991 PCT Filed Mar. 21, 1990 PCT Pub. No. WO90/11335 PCT Pub. Date Oct. 4, 1990.The novel ferroelectric liquid-crystalline mixtures are based on at least two mixture components of the general formula (I) (I) but additionally contain at least one optically active dope from one or more of the following groups a) optically active esters of tetrahydrofuran-2-carboxylic acid b) optically active aryl 2,3-epoxyalkyl ethers c) optically active 1,3-dioxolan-4-yl ethers. The ferroelectric LC mixtures have a high spontaneous polarization and facilitate substantial compensation of the pitch of the helix in a nematic phase.

    120.
    发明专利
    未知

    公开(公告)号：NO922978D0

    公开(公告)日：1992-07-28

    申请号：NO922978

    申请日：1992-07-28

    Applicant: HOECHST AG

    Inventor： ILLIAN GERHARD ,  MUELLER INGRID ,  HARADA TAKAMASA

    IPC: C07C13/16 ,  C07C69/86 ,  C07C15/02 ,  C07C43/20 ,  C07C69/92 ,  C07C69/94 ,  C07C69/96 ,  C07D20060101 ,  C07D213/30 ,  C07D239/26 ,  C07D239/34 ,  C07D239/38 ,  C07D285/12 ,  C07D405/12 ,  C07D417/12 ,  C07F7/08 ,  C09K19/08 ,  C09K19/20 ,  C09K19/34 ,  C09K19/42 ,  C09K19/46 ,  G02F1/13 ,  C07D

    Abstract: PCT No. PCT/EP91/00129 Sec. 371 Date Jul. 24, 1992 Sec. 102(e) Date Jul. 24, 1992 PCT Filed Jan. 24, 1991 PCT Pub. No. WO91/11441 PCT Pub. Date Aug. 8, 1991.Geminal dimethylalkyl compounds, process for their preparation and their use in liquid-crystalline mixtures Geminal dimethylalkyl compounds of the formula (I) (I) in which: R1 is, for example, straight-chain or branched (with or without an asymmetric carbon atom) alkyl or alkenyl having 2 to 16 carbon atoms, A1, A2 and A3 are, for example, identical or different 1,4-phenylene, 1,4-cyclohexylene or pyrimidine-2,5-diyl, M1 and M2 are, for example, identical or different CO-O or O-CO, G is for example, identical or different straight-chain or branched alkylene having 1 to 16 carbon atoms, k, l, m and n are zero or 1, and R6 is straight-cain alkyl having 1 to 10 carbon atoms, can advantageously be employed in liquid-crystalline mixtures. In liquid-crystalline mixtures, said compounds result in a melting point depression, in a shift in the temperature limit of the Sc phase in ferroelectric mixtures and in other improvements of important electrooptical characteristic values.

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