Dissolution of Phthalocyanines in Dense Carbon Dioxide and Its Solvatochromic Behavior under Pressureized Conditions

Metallophthalocyanines having alkoxy groups have been found to dissolve in dense carbon dioxide in the presence of small amount of cosolvent such as methanol or pyridine. The pressure dependence of the absorption maximum of these phthalocyanines can be used as an indicator for measuring solvent polarity.