Thermal Direct printers are capable of printing only on thermally treated (heat sensitive) label stationery. If you wish to print on plain paper or plastic label stationery you will need a Thermal Transfer printer. Thermal Direct labels are susceptible to the background going dark grey if the paper is exposed to heat or strong direct sunlight and will be easily marked if the paper surface is rubbed with, say, a fingernail. Thermal direct labels tend to be less susceptible to this effect than is thermal paper, because the label material is generally thicker than receipt paper. Like all thermal papers though, the print image will also fade over time.