Wire and cable insulation is typically made from thermoplastics, thermosets or fibrous coatings such as fiberglass and fiber-braiding. Unfortunately for manufacturers, inks and coatings do not print or bond well to most of these materials when using standard techniques.
There are several reasons for this. The materials have low levels of surface polarity, as well as poor wettability and adhesion properties. In addition, the materials usually do not receive surface modification prior to marking and coding, and they are sometimes exposed to a harsh or extreme environment that adds stress and further prevents adhesion. These limitations make it difficult for some manufacturers, such as those in the automotive and aerospace industries, to apply high-performance marking to their wire and cable harnesses.