The light stability of various ink-jet dyes has been studied on several types of nanoporous, nanocrystalline ink-jet materials (γ-Al2O3, ZrO2, SiO2, AlOOH, rare-earth doped Aloxides). The following parameters influencing light
stability will be discussed: chemical properties of the metal oxides, pore diameter, pore volume, surface charge (sign and density), dye adsorption, dye aggregation and dilution in inks. Catalytic fading in nanoporous media is in relation with porosity. Various methods to increase the light
stability of inks in such media are discussed. A possible mechanism to explain the photolytic degradation of ink-jet dyes in nanoporous materials is proposed. Gas fading was studied using different environmental gases under well defined conditions. The overall stability of inks
in nanoporous media depends on other parameters than in polymer layers. Therefore, improvements in nanoporous layers were also made using other tools.