Having a benzene ring which is bonded to the para-substituent by the meta-position of both adjacent to the pyran oxygen, photochromic fused naphthopyran

摘要

It adjoins this invention, to pyrane oxygen and it possesses the benzene ring which is joined to the para substituent by the both meta position, photochromic condensation nahutopiran, and the use in, the plastic of all types of especially ophthalmology application it regards.