Reduction of Ozone Fading of Copper Phthalocyanine Dyes by Non-traditional Antiozonants

Abstract

Ozone fading of printed images has been an important issue in digital imaging industries. Copper phthalocyanine dyes, widely used in imaging products, are highly susceptible to ozone fading. Mixing of dyes with conventional antiozonants, used in other non-imaging industrial products, is usually not suitable for systems where the dyes are required to be in solution, due to the relatively lower solubility of these antiozonants in aqueous or solvent systems. Some of these efficient antiozonants also react with air, resulting in highly colored compounds, which make them unsuitable for imaging products. The presence of suitable functional groups in the antiozonant molecules can reduce both these problems. The results presented in this paper show that several compounds, which are not used as typical antiozonants, improve ozone stability of copper phthalocyanine dyes to significant extents, with minimal colorimetric shifts. The effects of substituents on these antiozonant molecules and the possible mechanisms of the antiozonant effect are also discussed in this paper.