spiropyran derivatives with photochromischen properties

摘要

the present application relates to a structure of a lever, particularly usable in them are of type comprising a hull which is associated with at least one worn this.this structure consists of an arm lever, free, and a support associated with the worn this.the arm lever and support have at least one seat for the guide and / or the delay of at least two wires at the ends connected respectively to the worn this or the hull and to the support.these two elements of traction link to fly arm lever and the support so as to force the arm lever the wanted direction of opening condition.