FORMATION AND STUDY OF THIN-FILMS OF TERT-BUTYL-SUBSTITUTED THIOPYRYLIUM DYES

The formation of thin films of symmetrical and asymmetrical thiopyryli um dyes, containing tert-butyl substituents, on glass supports was stu died. The films were deposited by centrifugation of solutions of indiv idual dyes or dye-polymer [poly(methyl methacrylate)] compositions. Th e dye : polymer ratios necessary for the formation of WORM recording l ayers based on these dyes were determined. The use of a polymeric matr ix increases the film thickness and optical density but decreases its reflection power and does not allow crystallization of the dye on the support to be completely avoided. An increase in the number of tert-bu tyl groups in the dye molecule prevents crystallization of the recordi ng layer in the case of symmetrical dye molecules, but does not preven t it for asymmetrical molecules. The data obtained were interpreted in terms of geometrical views on the interaction of dye molecules in thi n layers.