Light-caused Colour Change-Scribing Foil with Light-Sensitive Layer

The effect in which images occur due to the exposure of a substance that causes the change of its colour is known as light-caused colour change.The method described in this paper is the direct image display without development after exposure of a lightsensitive lager made of PVK、CBr₄ and indicator.Stable image can be obtained by simple fixing process.So the operation is vary easy.Further more,this kind of layer can be refreshed,i.c.it can be reused after the previous image is removed without any other processes.Now it is used on scribing foils to make the layer light-sensitive.