There are two main types of thermal barcode labels: direct thermal and thermal transfer. Direct thermal labels are created by applying heat to a special type of paper that reacts to heat and turns black. Thermal transfer labels are created by applying heat to a ribbon that contains ink. The ink is then transferred to the label, creating a permanent image.
Direct thermal labels are a good option for short-term labeling applications where the labels will not be exposed to sunlight, moisture or extreme temperatures. Thermal transfer labels are ideal for longer term applications where durability and longevity are important.