| CPC G01K 11/12 (2013.01) [G01K 1/02 (2013.01); G01K 3/04 (2013.01)] | 31 Claims |

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1. An excess heat exposure indicator, comprising:
a print media substrate comprising an indicator region and a data region; and
at least one first thermochromic composition provided on the substrate within the indicator region of the substrate, the first thermochromic composition configured to change color state from a first color state to a second color state when exposed to a temperature above a first predetermined temperature threshold;
wherein a second thermochromic composition provided on the substrate within the data region, the second thermochromic composition configured to change color state from a third color state to a fourth color state when heated above a second predetermined temperature threshold, wherein the second predetermined temperature threshold is higher than the first predetermined temperature threshold;
wherein the indicator region is selectively treated with heat above the first predetermined temperature threshold to place a first portion of the indicator region including the first thermochromic composition in the second color state, different than the first color state while leaving a remaining portion of the indicator region including the first thermochromic composition in the first color state, forming a visible indicia, the visible indicia configured to change appearance when the remaining portion of the indicator region is subsequently exposed to a temperature above the first predetermined temperature threshold.
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