Tamper-proof label – this is a term for a multiplicity of diverse labels which serve as theft protection or make the products tamper-proof because of their special characteristics.
They support various safety requirements. The most simple types are paper labels with a security blanking as, for example, they are used for price labels in the retail trade. Because of the blanking it is very difficult to transfer the label in one single piece.
By using special foil materials, however, further security requirements can be realised. So, for example, labels can be furnished with special glue that leaves a distinctly and visibly „VOID”-lettering (so-called VOID labels) or a checkerboard pattern (so-called checkerboard labels) when the labels are pulled off. If such a label is once more glued onto a surface one is aware of its having been transferred.
An additional possibility exists in using special document foil. These labels adhere very strongly but they possess an unstable structure. When somebody tries to pull off these labels they crumble away into lots of small pieces.