| 摘要 |
The invention provides a security label 10 which includes a base layer 16 to which at least two coatings defining the first and second zones 12 and 14 are applied. The first zone 12 is defined by a thermochromic coating which irreversibly changes colour when the label 10 is heated above a desired temperature which may be negative or positive. The colour it changes to upon being exposed to heat is grey or black. The thermochromic coating defining the first zone 12 is applied to the base layer 16 using a printing process. The second zone 14 is defined by a coating that irreversibly changes colour or smudges when exposed to a liquid or a vapour. |
