Process for coating a polycarbonate containing base.

摘要

Provided is a process and solvent solution for coating an aza-annulene chromophore containing film directly onto a polycarbonate or polymethylmethacrylate comprising base. In the process, a solution of the chromophore, e.g., phthalocyanine, porphyrin or naphthalocyanine, is cast directly onto the polycarbonate or polymethylmethacrylate base, with the solvent used in formulating the solution comprising a C5-C7 cyclic alcohol, or a mixture or solvents including at least one of the aforementioned alcohols. The solvent is then removed, preferably by evaporation, in order to yield a smooth, homogeneous chromophore containing film directly on the polycarbonate or polymethylmethacrylate comprising base. This process is particularly applicable to the manufacture of optical recording media as the particular solvents employed in the process exhibit surprising and unique solvency characteristics with respect to aza-annulene chromophores, and do not attack polycarbonate or polymethylmethacrylate containing bases. The process therefore offers the advantage of being able to manufacture a medium employing a polycarbonate or polymethylmethacrylate substrate without the need for a subbing layer.