There are two kinds of thermal label printers: direct thermal and thermal transfer.
Direct thermal printing creates an image by heating a specially-coated paper, causing a chemical reaction that creates an image.
Thermal transfer printing uses specialized inked film ribbons to print on specialized thermal transfer papers or synthetic media.
Direct thermal printing is typically slightly less expensive but produces images that are less durable under difficult conditions; whereas thermal transfer printing creates long-lasting, very durable images that are reliable in challenging environments - such as extreme cold or heat, UV light exposure or exposure to chemicals and solvents.
Thermal printers are highly reliable and optimally designed for label-printing, which means they are ideal for printing one or thousands of labels at a time. Thermal images have high density with sharp edge definition and the right combination of ribbon and media results in a very durable, scratch- and solvent-resistant image without over-laminating. Adhesive bleed is not an issue for thermal printers, as their operating temperatures are much lower than laser fuser stations. Consequently, thermal printers are the printer of choice for bar code label printing.