Patent ID: 8647735

Claim:
A heating article comprising a substrate heatable to a temperature range of between 50° C. and 400° C. (T 1 ) and having a surface; and a design applied to at least a portion of said surface, wherein the design is in the form of a coating layer having at least one pattern, wherein the at least one pattern comprises a thermochromic pigment composition including at least one thermochromic semiconducting pigment that is lipid-sensitive under heat, wherein said thermochromic pigment composition includes: composite pigment grains having a core-envelope structure with a diameter of between 20 nm and 25,000 nm and each of which include: a core including said thermochromic semiconducting pigment; and a solid, transparent and continuous envelope formed from a mineral or organomineral hybrid material, and at least one thermostable pigment, wherein thermochromic pigment composition of the heating article shows a reversible change in color in a thermal color-change area with an amplitude of no more than 40° C. within the range of variation of said temperature T 1 .