Illuminometers containing photochromatic substances.

摘要

Disclosed are instruments for measuring light intensity, the so-said "illuminometers", which are constituted by a suitably shaped polymeric material containing, either coated on its surface, or incorporated inside its mass, at least one photochromatic compound belonging to the class of spiro-indolino-naphthooxazines and definable by the following general formula (I): <CHEM> in which the various substituents have the meanings as reported in the following disclosure.