Polymerizable dichroic dyes

A dichroic dye of formula (I):

• wherein
• X1 is NR or S,
• X2 is a single bond, NR, S or O,
• Y1, Y2 independently from each other are a single bond, NR, S or O,
• Z1, Z2 independently from each other are a single bond, NR, S or O,
• R represents hydrogen, unbranched or branched lower alkyl radical,
• W1, W2, W3, W4, W5, W6 independently from each other are H, unsubstituted or substituted, unbranched or branched C1-C30 alkyl radical, in which one or more —CH— or —CH2— group may be replaced by a linking group,
• PG is a polymerizable group,
• n1, n2, n3, n4, n5, n6 independently from each other signifies 0, 1, 2, 3, 4, 5 or 6 whereby the sum of n1, n2, n3, n4, n5 and n6 is ≧1,
• with the proviso that if n1, n2, n3, n4, n5 or n6=0, the connected W1, W2, W3, W4, W5, W6 have to be saturated by hydrogen.