Photoreactive plastics lenses are disclosed which are coated or impregnated with an adamantane 2-spiro-benzo or naphthopyran and with a blue colouring pho tochromic 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 colouring adamantane 2-spiro pyran compound with the purple/blue colouring pyran gives a desired brown/grey colouration in the sunlight-darkened lens. The invention includes novel blue-colouring 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.
已公开的光活性塑料镜片涂有或浸渍有
金刚烷 2-螺苯并
吡喃或
萘并
吡喃,以及在
吡喃环的 2 位上有含氮取代基的蓝色着色苯并
吡喃或
萘并
吡喃。镜片在阳光下会变暗,在环境温度下,在黑暗或不含紫外线成分的白光中会迅速褪色。黄色/橙色着色
金刚烷-2-螺
吡喃化合物与紫色/蓝色着色
吡喃化合物的组合使日光下变暗的镜片呈现出理想的棕色/灰色。本发明包括新型蓝色着色
吡喃化合物,其中 2-位上的含氮取代基是苯基,苯基的正位或对位上有
氨基或取代
氨基或含氮杂环取代基。