| abstract |
A naphthopyran compound represented by the formula: <IMAGE> wherein R1, R2, R5, R6, R7, R8, R9, and R10 are each selected from the group consisting essentially of hydrogen, a stable organic radical, a heterocyclic group, a halogen, a nitrogen-substituted group, and a nitrogen-substituted ring compound and wherein A is a substituted divalent aromatic radical that includes substituents selected from the group consisting essentially of hydrogen and the stable organic radical. |