| 摘要 |
Liq. crystal allenes of formula M-X<1>-C(R<1>)=C=CR<2>R<3> (I) in which definitions R<2> and R<3> are interchangeable are claimed, as are also (i) their prepn. by reaction of an allene of formula HX<2>-(CH2)p-C(R<1>)=C=CR<2>R<3> (II) with a cpd. of formula M-X<3> (III); (ii) allene intermediates of formulae HX<2>-(CH2)p-C(R<1>a)=C=CR<2>R<3>a (IIA), (IVA) and (IVB); and (iii) the use of (I) in optical displays, electro-optical storage media, electrophotographic appts. or light-reflecting sheets or layers. In the formulae, M = mesogenic gp.; R<1> and R<2> = H or 1-8C organic gp.; R<1>a = 1-8C organic gp.; R<3> = 1-30C organic gp.; R<3>a = 7-30C organic gp.; X<1> = -(CH2)q-Y.(CH2)p-; Y = -O-, -NR<4>-, -CO.O-, -O.CO-, -CO.NH<4>- or -NR<4>.CO-; R<4> = H or 1-4C alkyl; p and q = 1-20 and 0-20 resp.; X<2> = -O-, -NR<4>- or -O.CO-; and X<3> = gp. reacting with HX<2> to form an ether, amino, ester or amide linkage. |
