THE SECURITY THREAD DETECTABLE WITH LASER

摘要

A laser sensitive security hidden line is provided to secure device sensitivity by absorbing, scattering, and reflecting a light source before the light source reaches a light receiving unit, by transiting a laser source reacting pigment absorbing, scattering, and reflecting a laser source, on a transparent synthetic resin film by printing and coating. A laser sensitive security hidden line is produced by transiting a helium-neon laser source reacting pigment on one surface of a transparent synthetic resin film(1) used as a base material of the security hidden line, by printing or coating. The helium-neon laser source reacting pigment is produced by adding metallic ink containing aluminum powder of 10wt.% having the grain size of 10~12 micrometers, to a mixed solvent of alcohol and urethane resin varnish at the concentration of 5~15%.