Abstract

Frixion Roller Termochromic ink pens are incorporated with an erasure in each pen, which can be used to generate heat through friction which, in turn, decolourize the writings. Application of heat by other sources also have a similar effect. Termal ink has a unique characteristic which makes it disappear, when heat is applied at a specifc temperature. Due to this signifcant property of thermal ink, it is widely used for frauds. Easy availability and the unique characteristic of thermal inks attracts criminal minds and therefore increases criminal activities. Te main purpose of this research paper is to describe different properties of thermal ink along with the derivation of an easy, inexpensive and non-destructive process to restore disappeared writings. Reaction of thermochromic ink with different varieties of papers has also been examined in this paper.
 

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