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Abstract

Photoreactive plastics lenses are disclosed which are coated or impregnated with an adamantane 2-spiro-benzo or naphthopyran and with a blue coloring photochromic benzo- or naphthopyran having a nitrogen containing substituent in the 2-position in the pyran ring. The lenses darken in sunlight and fade rapidly at ambient temperatures in the dark or in white light which does not contain a U.V. component. The combination of the yellow/orange coloring adamantane 2-spiro pyran compound with the purple/blue coloring pyran gives a desired brown/grey coloration in the sunlight-darkened lens. The invention includes novel blue-coloring pyran compounds in which the nitrogen-containing substituent in the 2-position is a phenyl group having an amino or substituted amino or nitrogen-containing heterocyclic substituent in the ortho- or para-position of the phenyl group. The basic chromene structure and the suffix N will be used to distinguish the blue-coloring pyran compounds having a nitrogen-containing substituent, namely: ##STR1##

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First Claim