Security threads and security paper using the same.

摘要

The specification discloses with reference to Figure 1, a security thread (11) for use in security articles (10), said thread (11) comprising a substrate having a coating on one or both sides of the substrate, said coating containing a thermochromic material selected from pigments and dyestuffs which material changes from coloured to colourless when the temperature of said pigment or dyestuff is changed to the activation temperature. The thermochromic material may be coloured when the temperature is below the activation temperature and becomes colourless when the material is at the activation temperature or above. The thread (11) is for security paper (10) for use in producing banknotes and the like.