| abstract |
A heat indicator, a heat indicating composition (1), and two kinds of heat indicating structures (11) are disclosed. The heat indicator is in contact with the organic solid material (2) having a melting point above ambient temperature and the organic solid material (2), and when the heat indicator is heated to the melting point of the organic solid material (2), the organic solid material ( And a dye (3) which is soluble in 2). The heat indicator, the heat indicating composition (1), and the two kinds of heat indicating structures (1) have a simple structure and can be manufactured by a simple process. Furthermore, the presence of the dye (3) in a crystalline state significantly improves the resistance to ultraviolet rays in outdoor applications. |