Thermal printing is a printing method that does not use ink, ribbons or toner. Instead, the image is formed solely through heat activation. The print head heats the surface of the label material, which is coated with a special coating. This coating reacts to heat by turning black.
Glossary
thickness
Thickness is usually the distance between two parallel surfaces, from one surface to another. Usually expressed in mils (thousandths of an inch) or microns. Usually measured with a special device under slight pressure.