Azo compound.

摘要

An azo compound of the formula: wherein R is an non-hydrophilic aliphatic or cycloaliphatic group containing from 8 to 40 carbon atoms; m is 0 or 1; R<1> is NO2, CN or COOR<2>; R<2> is H or C1-4-alkyl; n is from 1 to 4 and R<3> is H, a metal or a group containing a tetravalent N atom. The compoound has non-linear optical properties which make it suitable for use in an optical element such as a waveguide, for altering the characteristics of light passing through the element.