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Polarizers containing disazo dyes from the group of azobenzene-azonaphthalene have been developed. It has been established that their polarizing ability is determined by the mutual disposition of the azo group and electron-donor substituents in the naphthalene ring. On diazo coupling of γ acid into the α position relative to the oxy group, the M 1 and M 3 dyes are formed, the polarizing ability of which in uniaxially oriented polyvinyl-alcohol films is higher than in the M 2 dye produced as a result of diazo coupling into the α position relative to the amino group. On irradiation by UV light, the dyes are subjected to photodestruction, which, in the case of M 2 , proceeds through trans-cis-isomerization. The rate of photodestruction depends on the aggregation of the dye molecules, and it increases in the presence of a free-radical initiator. The UV absorber (substituted benzotriazole) and the uniaxial orientation of the film retard this process.

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We present new mechanism of liquid crystal photoalignment based on reversible intermolecular bonds (hydrogen bonds or metal‐oxygen bonds) between dye molecules. This mechanism differs from known before and possesses temporal stability of photoinduced alignment against thermal disordering at room temperature. Predicted photoalignment dye was synthesized and verified in experiment.