| 摘要 |
Security paper is printed with a security ink including a security agent to a designed representation for detection by a short or longwave ultra-violet light source. The paper is provided with a specially formulated dense opaque coating which obscures the security representation. The coating provides a surface for printing by conventional techniques whilst the coating does not interfere with the desired detection of the phosphorescent or fluorescent security agent. The coating is applied as a slip and includes china clay in a binder having in an exemplary composition an acrylic resin with dispersant and selected wetting and keying agents. |
