Specially manufactured multi-layered plastics are available in many colour combinations. The top layer is cut away to expose the colour underneath. Most engraving plastics in use now are the ‘soft’ plastic type. These are flexible and easy to work with. Both indoor and outdoor grades are available. The outdoor grade has a thicker outer layer and properties to resist heat, light and UV exposure.
‘Hard’ engraving plastics once called ‘Traffolyte’ are still available, but are not as popular due to the greater difficulty to cut them, unsuitability for laser processes and dust problems.
Non-standard colour cominations can be obtained by paint filling. This can be a time-consuming process and can be expensive.
The common method of fixing plastic labels are by using double sided tape or screws. All tape fixing relies on the substrate (often a painted surface) being sound. Foam tapes with a thickness of about 0.8mm give good adhesion, especially where the underneath surface is textured. Very thin tapes (eg. tissue tapes and PVC tapes) adhere well to very flat surfaces, but poorly to anything with a texture.