Method of making a self-expiring identification badge using a thermal transfer printer

A method of making a self-expiring label or badge using a thermal transfer printer equipped with a transfer ribbon and a thermal print head, the method comprising the steps of:

• A. Contacting a first component of a dye system with a second component of the dye system, the first component carried on a facial surface of the transfer ribbon and the second component carried on a facial surface of a media, the second component beneath and in contact with a timing layer, and
• B. Heating the contacted first component of the dye system and timing layer with the thermal print head such that (i) the first component of the dye system transfers to the timing layer, and (ii) the first component of the dye system begins to migrate through the timing layer to the second component of the dye system which, upon contact of the first and second components of the dye system, an image is formed.